An effective hair detection algorithm for dermoscopic melanoma images of skin lesions

NASA Astrophysics Data System (ADS)

Chakraborti, Damayanti; Kaur, Ravneet; Umbaugh, Scott; LeAnder, Robert

2016-09-01

Dermoscopic images are obtained using the method of skin surface microscopy. Pigmented skin lesions are evaluated in terms of texture features such as color and structure. Artifacts, such as hairs, bubbles, black frames, ruler-marks, etc., create obstacles that prevent accurate detection of skin lesions by both clinicians and computer-aided diagnosis. In this article, we propose a new algorithm for the automated detection of hairs, using an adaptive, Canny edge-detection method, followed by morphological filtering and an arithmetic addition operation. The algorithm was applied to 50 dermoscopic melanoma images. In order to ascertain this method's relative detection accuracy, it was compared to the Razmjooy hair-detection method [1], using segmentation error (SE), true detection rate (TDR) and false positioning rate (FPR). The new method produced 6.57% SE, 96.28% TDR and 3.47% FPR, compared to 15.751% SE, 86.29% TDR and 11.74% FPR produced by the Razmjooy method [1]. Because of the 7.27-9.99% improvement in those parameters, we conclude that the new algorithm produces much better results for detecting thick, thin, dark and light hairs. The new method proposed here, shows an appreciable difference in the rate of detecting bubbles, as well.

Linear-array EUS improves detection of pancreatic lesions in high-risk individuals: a randomized tandem study

PubMed Central

Shin, Eun Ji; Topazian, Mark; Goggins, Michael G.; Syngal, Sapna; Saltzman, John R.; Lee, Jeffrey H.; Farrell, James J.; Canto, Marcia I.

2015-01-01

Background Studies comparing linear and radial EUS for the detection of pancreatic lesions in an asymptomatic population with increased risk for pancreatic cancer are lacking. Objectives To compare pancreatic lesion detection rates between radial and linear EUS and to determine the incremental diagnostic yield of a second EUS examination. Design Randomized controlled tandem study. Setting Five academic centers in the United States. Patients Asymptomatic high-risk individuals (HRIs) for pancreatic cancer undergoing screening EUS. Interventions Linear and radial EUS performed in randomized order. Main Outcome Measurements Pancreatic lesion detection rate by type of EUS, miss rate of 1 EUS examination, and incremental diagnostic yield of a second EUS examination (second-pass effect). Results Two hundred seventy-eight HRIs were enrolled, mean age 56 years (43.2%), and 90% were familial pancreatic cancer relatives. Two hundred twenty-four HRIs underwent tandem radial and linear EUS. When we used per-patient analysis, the overall prevalence of any pancreatic lesion was 45%. Overall, 16 of 224 HRIs (7.1%) had lesions missed during the initial EUS that were detected by the second EUS examination. The per-patient lesion miss rate was significantly greater for radial followed by linear EUS (9.8%) than for linear followed by radial EUS (4.5%) (P = .03). When we used per-lesion analysis, 73 of 109 lesions (67%) were detected by radial EUS and 99 of 120 lesions (82%) were detected by linear EUS (P < .001) during the first examination. The overall miss rate for a pancreatic lesion after 1 EUS examination was 47 of 229 (25%). The miss rate was significantly lower for linear EUS compared with radial EUS (17.5% vs 33.0%, P = .007). Limitations Most detected pancreatic lesions were not confirmed by pathology. Conclusion Linear EUS detects more pancreatic lesions than radial EUS. There was a “second-pass effect” with additional lesions detected with a second EUS examination. This effect was significantly greater when linear EUS was used after an initial radial EUS examination. PMID:25930097

Linear-array EUS improves detection of pancreatic lesions in high-risk individuals: a randomized tandem study.

PubMed

Shin, Eun Ji; Topazian, Mark; Goggins, Michael G; Syngal, Sapna; Saltzman, John R; Lee, Jeffrey H; Farrell, James J; Canto, Marcia I

2015-11-01

Studies comparing linear and radial EUS for the detection of pancreatic lesions in an asymptomatic population with increased risk for pancreatic cancer are lacking. To compare pancreatic lesion detection rates between radial and linear EUS and to determine the incremental diagnostic yield of a second EUS examination. Randomized controlled tandem study. Five academic centers in the United States. Asymptomatic high-risk individuals (HRIs) for pancreatic cancer undergoing screening EUS. Linear and radial EUS performed in randomized order. Pancreatic lesion detection rate by type of EUS, miss rate of 1 EUS examination, and incremental diagnostic yield of a second EUS examination (second-pass effect). Two hundred seventy-eight HRIs were enrolled, mean age 56 years (43.2%), and 90% were familial pancreatic cancer relatives. Two hundred twenty-four HRIs underwent tandem radial and linear EUS. When we used per-patient analysis, the overall prevalence of any pancreatic lesion was 45%. Overall, 16 of 224 HRIs (7.1%) had lesions missed during the initial EUS that were detected by the second EUS examination. The per-patient lesion miss rate was significantly greater for radial followed by linear EUS (9.8%) than for linear followed by radial EUS (4.5%) (P = .03). When we used per-lesion analysis, 73 of 109 lesions (67%) were detected by radial EUS and 99 of 120 lesions (82%) were detected by linear EUS (P < .001) during the first examination. The overall miss rate for a pancreatic lesion after 1 EUS examination was 47 of 229 (25%). The miss rate was significantly lower for linear EUS compared with radial EUS (17.5% vs 33.0%, P = .007). Most detected pancreatic lesions were not confirmed by pathology. Linear EUS detects more pancreatic lesions than radial EUS. There was a "second-pass effect" with additional lesions detected with a second EUS examination. This effect was significantly greater when linear EUS was used after an initial radial EUS examination. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Latest generation, wide-angle, high-definition colonoscopes increase adenoma detection rate.

PubMed

Adler, Andreas; Aminalai, Alireza; Aschenbeck, Jens; Drossel, Rolf; Mayr, Michael; Scheel, Mathias; Schröder, Andreas; Yenerim, Timur; Wiedenmann, Bertram; Gauger, Ulrich; Roll, Stephanie; Rösch, Thomas

2012-02-01

Improvements to endoscopy imaging technologies might improve detection rates of colorectal cancer and patient outcomes. We compared the accuracy of the latest generation of endoscopes with older generation models in detection of colorectal adenomas. We compared data from 2 prospective screening colonoscopy studies (the Berlin Colonoscopy Project 6); each study lasted approximately 6 months and included the same 6 colonoscopists, who worked in private practice. Participants in group 1 (n = 1256) were all examined by using the latest generation of wide-angle, high-definition colonoscopes that were manufactured by the same company. Individuals in group 2 (n = 1400) were examined by endoscopists who used routine equipment (a mixture of endoscopes from different companies; none of those used to examine group 1). The adenoma detection rate was calculated on the basis of the number of all adenomas/number of all patients. There were no differences in patient parameters or withdrawal time between groups (8.0 vs 8.2 minutes). The adenoma detection rate was significantly higher in group 1 (0.33) than in group 2 (0.27; P = .01); a greater number of patients with least 1 adenoma were identified in group 1 (22.1%) than in group 2 (18.2%; P = .01). A higher percentage of high-grade dysplastic adenomas were detected in group 1 (1.19%) than in group 2 (0.57%), but this difference was not statistically significant (P = .06). The latest generation of wide-angle, high-definition colonoscopes improves rates of adenoma detection by 22%, compared with mixed, older technology endoscopes used in routine private practice. These findings might affect definitions of quality control parameters for colonoscopy screening for colorectal cancer. Copyright © 2012 AGA Institute. Published by Elsevier Inc. All rights reserved.

Motion-compensated detection of heart rate based on the time registration adaptive filter

NASA Astrophysics Data System (ADS)

Yang, Lei; Zhou, Jinsong; Jing, Juanjuan; Li, Yacan; Wei, Lidong; Feng, Lei; He, Xiaoying; Bu, Meixia; Fu, Xilu

2018-01-01

A non-contact heart rate detection method based on the dual-wavelength technique is proposed and demonstrated experimentally. The heart rate is obtained based on the PhotoPlethysmoGraphy (PPG). Each detection module uses the reflection detection probe which is composed of the LED and the photodiode. It is a well-known fact that the differences in the circuits of two detection modules result in different responses of two modules for motion artifacts. It will cause a time delay between the two signals. This poses a great challenge to compensate the motion artifacts during measurements. In order to solve this problem, we have firstly used the time registration and translated the signals to ensure that the two signals are consistent in time domain. Then the adaptive filter is used to compensate the motion artifacts. Moreover, the data obtained by using this non-contact detection system is compared with those of the conventional finger blood volume pulse (BVP) sensor by simultaneously measuring the heart rate of the subject. During the experiment, the left hand remains stationary and is detected by a conventional finger BVP sensor. Meanwhile, the moving palm of right hand is detected by the proposed system. The data obtained from the proposed non-contact system are consistent and comparable with that of the BVP sensor. This method can effectively suppress the interference caused by the two circuit differences and successfully compensate the motion artifacts. This technology can be used in medical and daily heart rate measurement.

A comparative study of the TF-Test®, Kato-Katz, Hoffman-Pons-Janer, Willis and Baermann-Moraes coprologic methods for the detection of human parasitosis.

PubMed

Carvalho, Gabriela Lanna Xavier de; Moreira, Luciano Evangelista; Pena, João Luiz; Marinho, Carolina Coimbra; Bahia, Maria Terezinha; Machado-Coelho, George Luiz Lins

2012-02-01

This study compares the diagnostic accuracy of the TF-Test(®) (TFT) for human parasitosis with results obtained using the traditional Kato-Katz (KK), Hoffman-Pons-Janer (HPJ), Willis and Baermann-Moraes (BM) techniques. Overall, four stool samples were taken from each individual; three alternate-day TFT stool samples and another sample that was collected in a universal container. Stool samples were taken from 331 inhabitants of the community of Quilombola Santa Cruz. The gold standard (GS) for protozoa detection was defined as the combined results for TFT, HPJ and Willis coproscopic techniques; for helminth detection, GS was defined as the combined results for all five coproscopic techniques (TFT, KK, HPJ, Willis and BM). The positivity rate of each method was compared using the McNemar test. While the TFT exhibited similar positivity rates to the GS for Entamoeba histolytica/dispar (82.4%) and Giardia duodenalis (90%), HPJ and Willis techniques exhibited significantly lower positivity rates for these protozoa. All tests exhibited significantly lower positivity rates compared with GS for the diagnosis of helminths. The KK technique had the highest positivity rate for diagnosing Schistosoma mansoni (74.6%), while the TFT had the highest positivity rates for Ascaris lumbricoides (58.1%) and hookworm (75%); HPJ technique had the highest positivity rate for Strongyloides stercoralis (50%). Although a combination of tests is the most accurate method for the diagnosis of enteral parasites, the TFT reliably estimates the prevalence of protozoa and selected helminths, such as A. lumbricoides and hookworm. Further studies are needed to evaluate the detection accuracy of the TFT in samples with varying numbers of parasites.

Convolutional neural network based deep-learning architecture for prostate cancer detection on multiparametric magnetic resonance images

NASA Astrophysics Data System (ADS)

Tsehay, Yohannes K.; Lay, Nathan S.; Roth, Holger R.; Wang, Xiaosong; Kwak, Jin Tae; Turkbey, Baris I.; Pinto, Peter A.; Wood, Brad J.; Summers, Ronald M.

2017-03-01

Prostate cancer (PCa) is the second most common cause of cancer related deaths in men. Multiparametric MRI (mpMRI) is the most accurate imaging method for PCa detection; however, it requires the expertise of experienced radiologists leading to inconsistency across readers of varying experience. To increase inter-reader agreement and sensitivity, we developed a computer-aided detection (CAD) system that can automatically detect lesions on mpMRI that readers can use as a reference. We investigated a convolutional neural network based deep-learing (DCNN) architecture to find an improved solution for PCa detection on mpMRI. We adopted a network architecture from a state-of-the-art edge detector that takes an image as an input and produces an image probability map. Two-fold cross validation along with a receiver operating characteristic (ROC) analysis and free-response ROC (FROC) were used to determine our deep-learning based prostate-CAD's (CADDL) performance. The efficacy was compared to an existing prostate CAD system that is based on hand-crafted features, which was evaluated on the same test-set. CADDL had an 86% detection rate at 20% false-positive rate while the top-down learning CAD had 80% detection rate at the same false-positive rate, which translated to 94% and 85% detection rate at 10 false-positives per patient on the FROC. A CNN based CAD is able to detect cancerous lesions on mpMRI of the prostate with results comparable to an existing prostate-CAD showing potential for further development.

A novel balloon colonoscope detects significantly more simulated polyps than a standard colonoscope in a colon model.

PubMed

Hasan, Nazia; Gross, Seth A; Gralnek, Ian M; Pochapin, Mark; Kiesslich, Ralf; Halpern, Zamir

2014-12-01

Although standard colonoscopy is considered the optimal test to detect adenomas, it can have a significant adenoma miss rate. A major contributing factor to high miss rates is the inability to visualize adenomas behind haustral folds and at anatomic flexures. To compare the diagnostic yield of balloon-assisted colonoscopy versus standard colonoscopy in the detection of simulated polyps in a colon model. Prospective, cohort study. International gastroenterology meeting. A colon model composed of elastic material, which mimics the flexible structure of haustral folds, allowing for dynamic responses to balloon inflation, with embedded simulated colon polyps (n = 12 silicone "polyps"). Fifty gastroenterologists were recruited to identify simulated colon polyps in a colon model, first using standard colonoscopy immediately followed by balloon-assisted colonoscopy. Detection of simulated polyps. The median polyp detection rate for all simulated polyps was significantly higher with balloon-assisted as compared with standard colonoscopy (91.7% vs 45.8%, respectively; P < .0001). The significantly higher simulated polyp detection rate with balloon-assisted versus standard colonoscopy was notable both for non-obscured polyps (100.0% vs 75.0%; P < .0001) and obscured polyps (88.0% vs 25.0%; P < .0001). Non-randomized design, use of a colon model, and simulated colon polyps. As compared with standard colonoscopy, balloon-assisted colonoscopy detected significantly more obscured and non-obscured simulated polyps in a colon model. Clinical studies in human participants are being pursued to further evaluate this new colonoscopic technology. Copyright © 2014 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Heart Rate Detection During Sleep Using a Flexible RF Resonator and Injection-Locked PLL Sensor.

PubMed

Kim, Sung Woo; Choi, Soo Beom; An, Yong-Jun; Kim, Byung-Hyun; Kim, Deok Won; Yook, Jong-Gwan

2015-11-01

Novel nonintrusive technologies for wrist pulse detection have been developed and proposed as systems for sleep monitoring using three types of radio frequency (RF) sensors. The three types of RF sensors for heart rate measurement on wrist are a flexible RF single resonator, array resonators, and an injection-locked PLL resonator sensor. To verify the performance of the new RF systems, we compared heart rates between presleep time and postsleep onset time. Heart rates of ten subjects were measured using the RF systems during sleep. All three RF devices detected heart rates at 0.2 to 1 mm distance from the skin of the wrist over clothes made of cotton fabric. The wrist pulse signals of a flexible RF single resonator were consistent with the signals obtained by a portable piezoelectric transducer as a reference. Then, we confirmed that the heart rate after sleep onset time significantly decreased compared to before sleep. In conclusion, the RF system can be utilized as a noncontact nonintrusive method for measuring heart rates during sleep.

Endoscopic detection rate of sessile serrated lesions in Lynch syndrome patients is comparable with an age- and gender-matched control population: case-control study with expert pathology review.

PubMed

Vleugels, Jasper L A; Sahin, Husna; Hazewinkel, Yark; Koens, Lianne; van den Berg, Jose G; van Leerdam, Monique E; Dekker, Evelien

2018-05-01

Carcinogenesis in Lynch syndrome involves fast progression of adenomas to colorectal cancer (CRC) because of microsatellite instability. The role of sessile serrated lesions (SSLs) and the serrated neoplasia pathway in these patients is unknown. The aim of this matched case-control study was to compare endoscopic detection rates and distribution of SSLs in Lynch syndrome patients with a matched control population. We collected data of Lynch syndrome patients with a proven germline mutation who underwent colonoscopy between January 2011 and April 2016 in 2 tertiary referral hospitals. Control subjects undergoing elective colonoscopy from 2011 and onward for symptoms or surveillance were selected from a prospectively collected database. Patients were matched 1:1 for age, gender, and index versus surveillance colonoscopy. An expert pathology review of serrated polyps was performed. The primary outcomes included the detection rates and distribution of SSLs. We identified 321 patients with Lynch syndrome who underwent at least 1 colonoscopy. Of these, 223 Lynch syndrome patients (mean age, 49.3; 59% women; index colonoscopy, 56%) were matched to 223 control subjects. SSLs were detected in 7.6% (95% confidence interval, 4.8-11.9) of colonoscopies performed in Lynch syndrome patients and in 6.7% (95% confidence interval, 4.1-10.8) of control subjects (P = .86). None of the detected SSLs in Lynch syndrome patients contained dysplasia. The detection rate of SSLs in Lynch syndrome patients undergoing colonoscopy is comparable with a matched population. These findings suggest that the role of the serrated neoplasia pathway in CRC development in Lynch syndrome seems to be comparable with that in the general population. Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Detection of circulating tumor cells using oHSV1-hTERT-GFP in lung cancer.

PubMed

Gao, Hongjun; Liu, Wenjing; Yang, Shaoxing; Zhang, Wen; Li, Xiaoyan; Qin, Haifeng; Wang, Weixia; Zhao, Changyun

2018-01-01

This study was conducted to evaluate the clinical utility of the oHSV1-hTERT-GFP circulating tumor cell (CTC) detection method in the peripheral blood of patients with lung cancer by comparing its sensitivity to the CellSearch CTC detection method. The oHSV1-hTERT-GFP and CellSearch CTC detection methods were compared using peripheral blood samples of patients pathologically diagnosed with lung cancer. A total of 240 patients with lung cancer were recruited, including 89 patients who were newly diagnosed and 151 patients who had previously received treatment. Sixty-six newly diagnosed patients were evaluated using both methods. The CTC detection rates were 71.2% and 33.3% using the oHSV1-hTERT-GFP and CellSearch methods, respectively; this difference was statistically significant (P = 0.000). Among the entire cohort (n = 240), the CTC detection rate using the oHSV1-hTERT-GFP method was 76.3%, with a CTC count of 0-81. The CTC detection rates were 76.7%, 68.9%, and 76.3% in patients with squamous cell carcinoma, adenocarcinoma, and small cell lung cancer, respectively. There was no statistically significant difference in the CTC detection rates between these different pathological subtypes (P = 0.738). The CTC detection rates of 79.8% and 74.4% in patients with stage I-III and IV lung cancer, respectively, were not significantly different (P = 0.427). The oHSV1-hTERT-GFP method is highly effective for detecting CTCs in patients with lung cancer, independent of pathological type and disease stage, and is ideal for large-scale clinical applications. © 2017 The Authors. Thoracic Cancer published by China Lung Oncology Group and John Wiley & Sons Australia, Ltd.

Trend in case detection rate for all tuberculosis cases notified in Ebonyi, Southeastern Nigeria during 1999-2009.

PubMed

Ukwaja, Kingsley Nnanna; Alobu, Isaac; Ifebunandu, Ngozi Appolonia; Osakwe, Chijioke; Igwenyi, Chika

2013-01-01

Unlike previous annual WHO tuberculosis reports that reported case detection rate for only smear-positive tuberculosis cases, the 2010 report presented case detection rate for all tuberculosis cases notified in line with the current Stop TB strategy. To help us understand how tuberculosis control programmes performed in terms of detecting tuberculosis, there is need to document the trend in case detection rate for all tuberculosis cases notified in high burden countries. This evidence is currently lacking from Nigeria. Therefore, this study aimed to assess the trend in case detection rate for all tuberculosis cases notified from Ebonyi state compared to Nigeria national figures. Reports of tuberculosis cases notified between 1999 and 2009 were reviewed from the Ebonyi State Ministry of Health tuberculosis quarterly reports. Tuberculosis case detection rates were computed according to WHO guidelines. 22, 508 patients with all forms of tuberculosis were notified during the study. Case detection rate for all tuberculosis rose from 27% in 1999 to gradually reach a peak of 40% during 2007 to 2008 before a slight decline in 2009 to 38%. However, the national case detection rate for all tuberculosis cases in Nigeria rose from 7% in 1999 and progressively increased to reach a peak of 19% during 2008 and 2009. Since the introduction of DOTS in Ebonyi, the programme has achieved 40% case detection rate for all tuberculosis cases - about 20% better than national figures. However, with the current low case detection rates, alternative mechanisms are needed to achieve the current global stop- TB targets in Nigeria.

Evaluation of Sensor Technology to Detect Fall Risk and Prevent Falls in Acute Care.

PubMed

Potter, Patricia; Allen, Kelly; Costantinou, Eileen; Klinkenberg, William Dean; Malen, Jill; Norris, Traci; O'Connor, Elizabeth; Roney, Wilhemina; Tymkew, Heidi Hahn; Wolf, Laurie

2017-08-01

Sensor technology that dynamically identifies hospitalized patients' fall risk and detects and alerts nurses of high-risk patients' early exits out of bed has potential for reducing fall rates and preventing patient harm. During Phase 1 (August 2014-January 2015) of a previously reported performance improvement project, an innovative depth sensor was evaluated on two inpatient medical units to study fall characteristics. In Phase 2 (April 2015-January 2016), a combined depth and bed sensor system designed to assign patient fall probability, detect patient bed exits, and subsequently prevent falls was evaluated. Fall detection depth sensors remained in place on two medicine units; bed sensors used to detect patient bed exits were added on only one of the medicine units. Fall rates and fall with injury rates were evaluated on both units. During Phase 2, the designated evaluation unit had 14 falls, for a fall rate of 2.22 per 1,000 patient-days-a 54.1% reduction compared with the Phase 1 fall rate. The difference in rates from Phase 1 to Phase 2 was statistically significant (z = 2.20; p = 0.0297). The comparison medicine unit had 30 falls-a fall rate of 4.69 per 1,000 patient-days, representing a 57.9% increase as compared with Phase 1. A fall detection sensor system affords a level of surveillance that standard fall alert systems do not have. Fall prevention remains a complex issue, but sensor technology is a viable fall prevention option. Copyright © 2017 The Joint Commission. Published by Elsevier Inc. All rights reserved.

Comparing the outcomes of two strategies for colorectal tumor detection: policy-promoted screening program versus health promotion service.

PubMed

Wu, Ping-Hsiu; Lin, Yu-Min; Liao, Chao-Sheng; Chang, Hung-Chuen; Chen, Yu-Hung; Yang, Kuo-Ching; Shih, Chia-Hui

2013-06-01

The Taiwanese government has proposed a population-based colorectal tumor detection program for the average-risk population. This study's objectives were to understand the outcomes of these screening policies and to evaluate the effectiveness of the program. We compared two databases compiled in one medical center. The "policy-promoted cancer screening" (PPS) database was built on the basis of the policy of the Taiwan Bureau of National Health Insurance for cancer screening. The "health promotion service" (HPS) database was built to provide health check-ups for self-paid volunteers. Both the PPS and HPS databases employ the immunochemical fecal occult blood test (iFOBT) and colonoscopy for colorectal tumor screening using different strategies. A comparison of outcomes between the PPS and HPS included: (1) quality indicators-compliance rate, cecum reaching rate, and tumor detection rate; and (2) validity indicators-sensitivity, specificity, positive, and negative predictive values for detecting colorectal neoplasms. A total of 10,563 and 1481 individuals were enrolled in PPS and HPS, respectively. Among quality indicators, there was no statistically significant difference in the cecum reaching rate between PPS and HPS. The compliance rates were 56.1% for PPS and 91.8% for HPS (p < 0.001). The advanced adenoma detection rates of PPS and HPS were 1.0% and 3.6%, respectively (p < 0.01). The carcinoma detection rates were 0.3% and 0.4%, respectively (p = 0.59). For validity indicators, PPS provides only a positive predictive value for colorectal tumor detection. HPS provides additional validity indicators, including sensitivity, specificity, positive predictive value, and negative predictive value, for colorectal tumor screening. In comparison with the outcomes of the HPS database, the screening efficacy of the PPS database is even for detecting colorectal carcinoma but is limited in detecting advanced adenoma. HPS may provide comprehensive validity indicators and will be helpful in adjusting current policies for improving screening performance. Copyright © 2013. Published by Elsevier B.V.

Assessing the role of spectral and intensity cues in spectral ripple detection and discrimination in cochlear-implant users.

PubMed

Anderson, Elizabeth S; Oxenham, Andrew J; Nelson, Peggy B; Nelson, David A

2012-12-01

Measures of spectral ripple resolution have become widely used psychophysical tools for assessing spectral resolution in cochlear-implant (CI) listeners. The objective of this study was to compare spectral ripple discrimination and detection in the same group of CI listeners. Ripple detection thresholds were measured over a range of ripple frequencies and were compared to spectral ripple discrimination thresholds previously obtained from the same CI listeners. The data showed that performance on the two measures was correlated, but that individual subjects' thresholds (at a constant spectral modulation depth) for the two tasks were not equivalent. In addition, spectral ripple detection was often found to be possible at higher rates than expected based on the available spectral cues, making it likely that temporal-envelope cues played a role at higher ripple rates. Finally, spectral ripple detection thresholds were compared to previously obtained speech-perception measures. Results confirmed earlier reports of a robust relationship between detection of widely spaced ripples and measures of speech recognition. In contrast, intensity difference limens for broadband noise did not correlate with spectral ripple detection measures, suggesting a dissociation between the ability to detect small changes in intensity across frequency and across time.

Low-complexity R-peak detection for ambulatory fetal monitoring.

PubMed

Rooijakkers, Michael J; Rabotti, Chiara; Oei, S Guid; Mischi, Massimo

2012-07-01

Non-invasive fetal health monitoring during pregnancy is becoming increasingly important because of the increasing number of high-risk pregnancies. Despite recent advances in signal-processing technology, which have enabled fetal monitoring during pregnancy using abdominal electrocardiogram (ECG) recordings, ubiquitous fetal health monitoring is still unfeasible due to the computational complexity of noise-robust solutions. In this paper, an ECG R-peak detection algorithm for ambulatory R-peak detection is proposed, as part of a fetal ECG detection algorithm. The proposed algorithm is optimized to reduce computational complexity, without reducing the R-peak detection performance compared to the existing R-peak detection schemes. Validation of the algorithm is performed on three manually annotated datasets. With a detection error rate of 0.23%, 1.32% and 9.42% on the MIT/BIH Arrhythmia and in-house maternal and fetal databases, respectively, the detection rate of the proposed algorithm is comparable to the best state-of-the-art algorithms, at a reduced computational complexity.

Lung cancer screening with low-dose helical CT in Korea: experiences at the Samsung Medical Center.

PubMed

Chong, Semin; Lee, Kyung Soo; Chung, Myung Jin; Kim, Tae Sung; Kim, Hojoong; Kwon, O Jung; Choi, Yoon-Ho; Rhee, Chong H

2005-06-01

To determine overall detection rates of lung cancer by low-dose CT (LDCT) screening and to compare histopathologic and imaging differences of detected cancers between high- and low-risk groups, this study included 6,406 asymptomatic Korean adults with >or=45 yr of age who underwent LDCT for lung cancer screening. All were classified into high- (>or=20 pack-year smoking; 3,353) and low-risk (3,053; <20 pack-yr smoking and non-smokers) groups. We compared CT findings of detected cancers and detection rates between high- and low-risk. At initial CT, 35% (2,255 of 6,406) had at least one or more non-calcified nodule. Lung cancer detection rates were 0.36% (23 of 6,406). Twenty-one non-small cell lung cancers appeared as solid (n=14) or ground-glass opacity (GGO) (n=7) nodules. Cancer likelihood was higher in GGO nodules than in solid nodules (p<0.01). Fifteen of 23 cancers occurred in high-risk group and 8 in low-risk group (p=0.215). Therefore, LDCT screening help detect early stage of lung cancer in asymptomatic Korean population with detection rate of 0.36% on a population basis and may be useful for discovering early lung cancer in low-risk group as well as in high-risk group.

Repeated Induction of Inattentional Blindness in a Simulated Aviation Environment

NASA Technical Reports Server (NTRS)

Kennedy, Kellie D.; Stephens, Chad L.; Williams, Ralph A.; Schutte, Paul C.

2017-01-01

The study reported herein is a subset of a larger investigation on the role of automation in the context of the flight deck and used a fixed-based, human-in-the-loop simulator. This paper explored the relationship between automation and inattentional blindness (IB) occurrences in a repeated induction paradigm using two types of runway incursions. The critical stimuli for both runway incursions were directly relevant to primary task performance. Sixty non-pilot participants performed the final five minutes of a landing scenario twice in one of three automation conditions: full automation (FA), partial automation (PA), and no automation (NA). The first induction resulted in a 70 percent (42 of 60) detection failure rate with those in the PA condition significantly more likely to detect the incursion compared to the FA condition or the NA condition. The second induction yielded a 50 percent detection failure rate. Although detection improved (detection failure rates declined) in all conditions, those in the FA condition demonstrated the greatest improvement with doubled detection rates. The detection behavior in the first trial did not preclude a failed detection in the second induction. Group membership (IB vs. Detection) in the FA condition showed a greater improvement than those in the NA condition and rated the Mental Demand and Effort subscales of the NASA-TLX (NASA Task Load Index) significantly higher for Time 2 compared Time 1. Participants in the FA condition used the experience of IB exposure to improve task performance whereas those in the NA condition did not, indicating the availability and reallocation of attentional resources in the FA condition. These findings support the role of engagement in operational attention detriment and the consideration of attentional failure causation to determine appropriate mitigation strategies.

Differential detection in quadrature-quadrature phase shift keying (Q2PSK) systems

NASA Astrophysics Data System (ADS)

El-Ghandour, Osama M.; Saha, Debabrata

1991-05-01

A generalized quadrature-quadrature phase shift keying (Q2PSK) signaling format is considered for differential encoding and differential detection. Performance in the presence of additive white Gaussian noise (AWGN) is analyzed. Symbol error rate is found to be approximately twice the symbol error rate in a quaternary DPSK system operating at the same Eb/N0. However, the bandwidth efficiency of differential Q2PSK is substantially higher than that of quaternary DPSK. When the error is due to AWGN, the ratio of double error rate to single error rate can be very high, and the ratio may approach zero at high SNR. To improve error rate, differential detection through maximum-likelihood decoding based on multiple or N symbol observations is considered. If N and SNR are large this decoding gives a 3-dB advantage in error rate over conventional N = 2 differential detection, fully recovering the energy loss (as compared to coherent detection) if the observation is extended to a large number of symbol durations.

What are incident reports telling us? A comparative study at two Australian hospitals of medication errors identified at audit, detected by staff and reported to an incident system.

PubMed

Westbrook, Johanna I; Li, Ling; Lehnbom, Elin C; Baysari, Melissa T; Braithwaite, Jeffrey; Burke, Rosemary; Conn, Chris; Day, Richard O

2015-02-01

To (i) compare medication errors identified at audit and observation with medication incident reports; (ii) identify differences between two hospitals in incident report frequency and medication error rates; (iii) identify prescribing error detection rates by staff. Audit of 3291 patient records at two hospitals to identify prescribing errors and evidence of their detection by staff. Medication administration errors were identified from a direct observational study of 180 nurses administering 7451 medications. Severity of errors was classified. Those likely to lead to patient harm were categorized as 'clinically important'. Two major academic teaching hospitals in Sydney, Australia. Rates of medication errors identified from audit and from direct observation were compared with reported medication incident reports. A total of 12 567 prescribing errors were identified at audit. Of these 1.2/1000 errors (95% CI: 0.6-1.8) had incident reports. Clinically important prescribing errors (n = 539) were detected by staff at a rate of 218.9/1000 (95% CI: 184.0-253.8), but only 13.0/1000 (95% CI: 3.4-22.5) were reported. 78.1% (n = 421) of clinically important prescribing errors were not detected. A total of 2043 drug administrations (27.4%; 95% CI: 26.4-28.4%) contained ≥ 1 errors; none had an incident report. Hospital A had a higher frequency of incident reports than Hospital B, but a lower rate of errors at audit. Prescribing errors with the potential to cause harm frequently go undetected. Reported incidents do not reflect the profile of medication errors which occur in hospitals or the underlying rates. This demonstrates the inaccuracy of using incident frequency to compare patient risk or quality performance within or across hospitals. New approaches including data mining of electronic clinical information systems are required to support more effective medication error detection and mitigation. © The Author 2015. Published by Oxford University Press in association with the International Society for Quality in Health Care.

Quantifying the utilization of medical devices necessary to detect postmarket safety differences: A case study of implantable cardioverter defibrillators.

PubMed

Bates, Jonathan; Parzynski, Craig S; Dhruva, Sanket S; Coppi, Andreas; Kuntz, Richard; Li, Shu-Xia; Marinac-Dabic, Danica; Masoudi, Frederick A; Shaw, Richard E; Warner, Frederick; Krumholz, Harlan M; Ross, Joseph S

2018-06-12

To estimate medical device utilization needed to detect safety differences among implantable cardioverter defibrillators (ICDs) generator models and compare these estimates to utilization in practice. We conducted repeated sample size estimates to calculate the medical device utilization needed, systematically varying device-specific safety event rate ratios and significance levels while maintaining 80% power, testing 3 average adverse event rates (3.9, 6.1, and 12.6 events per 100 person-years) estimated from the American College of Cardiology's 2006 to 2010 National Cardiovascular Data Registry of ICDs. We then compared with actual medical device utilization. At significance level 0.05 and 80% power, 34% or fewer ICD models accrued sufficient utilization in practice to detect safety differences for rate ratios <1.15 and an average event rate of 12.6 events per 100 person-years. For average event rates of 3.9 and 12.6 events per 100 person-years, 30% and 50% of ICD models, respectively, accrued sufficient utilization for a rate ratio of 1.25, whereas 52% and 67% for a rate ratio of 1.50. Because actual ICD utilization was not uniformly distributed across ICD models, the proportion of individuals receiving any ICD that accrued sufficient utilization in practice was 0% to 21%, 32% to 70%, and 67% to 84% for rate ratios of 1.05, 1.15, and 1.25, respectively, for the range of 3 average adverse event rates. Small safety differences among ICD generator models are unlikely to be detected through routine surveillance given current ICD utilization in practice, but large safety differences can be detected for most patients at anticipated average adverse event rates. Copyright © 2018 John Wiley & Sons, Ltd.

[Role of video electroencephalogram in diagnosis and localization of epilepsy in children].

PubMed

Yang, Xiao-Yan; Long, Li-Li; Xiao, Bo

2016-10-01

To study the role of video electroencephalogram (VEEG) versus regular electroencephalogram (REEG) in the diagnosis of epilepsy and localization of origin of epileptic discharge in children through a comparative analysis. A retrospective analysis was performed for the clinical data of 223 children with clinical paroxysmal symptoms in the past and suspected epilepsy. VEEG and REEG were compared from the aspects of monitoring of clinical seizures, interictal epileptiform discharge (IED), localization of the origin of IED, and identification of non-epileptic seizures, and the detection rate of IED during awakening and sleep stages was also compared. Compared with REEG, VEEG had significantly higher detection rates of IED and synchronous clinical seizures in children with epileptiform discharge (P<0.01). Of all children, 86 were diagnosed with epilepsy, 78 were diagnosed with epilepsy syndrome, 31 were diagnosed with non-epileptic seizures, and 81 had a definite location of the origin of epileptic discharge according to the VEEG. The detection rate of IED in the sleep stage was higher than that in the awakening stage (46% vs 13.2%; P<0.01), and IED was mainly detected in the NREM I-II stages according to the VEEG. VEEG has a significantly better performance than REEG in the diagnosis and localization of epilepsy in children and has a high value in clinical practice.

The best prostate biopsy scheme is dictated by the gland volume: a monocentric study.

PubMed

Dell'Atti, L

2015-08-01

Accuracy of biopsy scheme depends on different parameters. Prostate-specific antigen (PSA) level and digital rectal examination (DRE) influenced the detection rate and suggested the biopsy scheme to approach each patient. Another parameter is the prostate volume. Sampling accuracy tends to decrease progressively with an increasing prostate volume. We prospectively observed detection cancer rate in suspicious prostate cancer (PCa) and improved by applying a protocol biopsy according to prostate volume (PV). Clinical data and pathological features of these 1356 patients were analysed and included in this study. This protocol is a combined scheme that includes transrectal (TR) 12-core PBx (TR12PBx) for PV ≤ 30 cc, TR 14-core PBx (TR14PBx) for PV > 30 cc but < 60 cc, TR 18-core PBx (TR18PBx) for PV ≥ 60 cc. Out of a total of 1356 patients, in 111 (8.2%) PCa was identified through TR12PBx scheme, in 198 (14.6%) through TR14PBx scheme and in 253 (18.6%) through TR18PBx scheme. The PCa detection rate was increased by 44% by adding two TZ cores (TR14PBx scheme). The TR18PBx scheme increased this rate by 21.7% vs. TR14PBx scheme. The diagnostic yield offered by TR18PBx was statistically significant compared to the detection rate offered by the TR14PBx scheme (p < 0.003). The biopsy Gleason score and the percentage of core involvement were comparable between PCa detected by the TR14PBx scheme diagnostic yield and those detected by the TR18PBx scheme (p = 0.362). The only PV parameter, in our opinion, can be significant in choosing the best biopsy scheme to approach in a first setting of biopsies increasing PCa detection rate.

Automatic detection of diabetic retinopathy using an artificial neural network: a screening tool.

PubMed

Gardner, G G; Keating, D; Williamson, T H; Elliott, A T

1996-11-01

To determine if neural networks can detect diabetic features in fundus images and compare the network against an ophthalmologist screening a set of fundus images. 147 diabetic and 32 normal images were captured from a fundus camera, stored on computer, and analysed using a back propagation neural network. The network was trained to recognise features in the retinal image. The effects of digital filtering techniques and different network variables were assessed. 200 diabetic and 101 normal images were then randomised and used to evaluate the network's performance for the detection of diabetic retinopathy against an ophthalmologist. Detection rates for the recognition of vessels, exudates, and haemorrhages were 91.7%, 93.1%, and 73.8% respectively. When compared with the results of the ophthalmologist, the network achieved a sensitivity of 88.4% and a specificity of 83.5% for the detection of diabetic retinopathy. Detection of vessels, exudates, and haemorrhages was possible, with success rates dependent upon preprocessing and the number of images used in training. When compared with the ophthalmologist, the network achieved good accuracy for the detection of diabetic retinopathy. The system could be used as an aid to the screening of diabetic patients for retinopathy.

Sentinel Lymph Node Detection Using Carbon Nanoparticles in Patients with Early Breast Cancer

PubMed Central

Lu, Jianping; Zeng, Yi; Chen, Xia; Yan, Jun

2015-01-01

Purpose Carbon nanoparticles have a strong affinity for the lymphatic system. The purpose of this study was to evaluate the feasibility of sentinel lymph node biopsy using carbon nanoparticles in early breast cancer and to optimize the application procedure. Methods Firstly, we performed a pilot study to demonstrate the optimized condition using carbon nanoparticles for sentinel lymph nodes (SLNs) detection by investigating 36 clinically node negative breast cancer patients. In subsequent prospective study, 83 patients with clinically node negative breast cancer were included to evaluate SLNs using carbon nanoparticles. Another 83 SLNs were detected by using blue dye. SLNs detection parameters were compared between the methods. All patients irrespective of the SLNs status underwent axillary lymph node dissection for verification of axillary node status after the SLN biopsy. Results In pilot study, a 1 ml carbon nanoparticles suspension used 10–15min before surgery was associated with the best detection rate. In subsequent prospective study, with carbon nanoparticles, the identification rate, accuracy, false negative rate was 100%, 96.4%, 11.1%, respectively. The identification rate and accuracy were 88% and 95.5% with 15.8% of false negative rate using blue dye technique. The use of carbon nanoparticles suspension showed significantly superior results in identification rate (p = 0.001) and reduced false-negative results compared with blue dye technique. Conclusion Our study demonstrated feasibility and accuracy of using carbon nanoparticles for SLNs mapping in breast cancer patients. Carbon nanoparticles are useful in SLNs detection in institutions without access to radioisotope. PMID:26296136

Numerical study on the sequential Bayesian approach for radioactive materials detection

NASA Astrophysics Data System (ADS)

Qingpei, Xiang; Dongfeng, Tian; Jianyu, Zhu; Fanhua, Hao; Ge, Ding; Jun, Zeng

2013-01-01

A new detection method, based on the sequential Bayesian approach proposed by Candy et al., offers new horizons for the research of radioactive detection. Compared with the commonly adopted detection methods incorporated with statistical theory, the sequential Bayesian approach offers the advantages of shorter verification time during the analysis of spectra that contain low total counts, especially in complex radionuclide components. In this paper, a simulation experiment platform implanted with the methodology of sequential Bayesian approach was developed. Events sequences of γ-rays associating with the true parameters of a LaBr3(Ce) detector were obtained based on an events sequence generator using Monte Carlo sampling theory to study the performance of the sequential Bayesian approach. The numerical experimental results are in accordance with those of Candy. Moreover, the relationship between the detection model and the event generator, respectively represented by the expected detection rate (Am) and the tested detection rate (Gm) parameters, is investigated. To achieve an optimal performance for this processor, the interval of the tested detection rate as a function of the expected detection rate is also presented.

Prospective randomized trial comparing magnetic resonance imaging (MRI)-guided in-bore biopsy to MRI-ultrasound fusion and transrectal ultrasound-guided prostate biopsy in patients with prior negative biopsies.

PubMed

Arsov, Christian; Rabenalt, Robert; Blondin, Dirk; Quentin, Michael; Hiester, Andreas; Godehardt, Erhard; Gabbert, Helmut E; Becker, Nikolaus; Antoch, Gerald; Albers, Peter; Schimmöller, Lars

2015-10-01

A significant proportion of prostate cancers (PCas) are missed by conventional transrectal ultrasound-guided biopsy (TRUS-GB). It remains unclear whether the combined approach using targeted magnetic resonance imaging (MRI)-ultrasound fusion-guided biopsy (FUS-GB) and systematic TRUS-GB is superior to targeted MRI-guided in-bore biopsy (IB-GB) for PCa detection. To compare PCa detection between IB-GB alone and FUS-GB + TRUS-GB in patients with at least one negative TRUS-GB and prostate-specific antigen ≥4 ng/ml. Patients were prospectively randomized after multiparametric prostate MRI to IB-GB (arm A) or FUS-GB + TRUS-GB (arm B) from November 2011 to July 2014. The study was powered at 80% to demonstrate an overall PCa detection rate of ≥60% in arm B compared to 40% in arm A. Secondary endpoints were the distribution of highest Gleason scores, the rate of detection of significant PCa (Gleason ≥7), the number of biopsy cores to detect one (significant) PCa, the positivity rate for biopsy cores, and tumor involvement per biopsy core. The study was halted after interim analysis because the primary endpoint was not met. The trial enrolled 267 patients, of whom 210 were analyzed (106 randomized to arm A and 104 to arm B). PCa detection was 37% in arm A and 39% in arm B (95% confidence interval for difference, -16% to 11%; p=0.7). Detection rates for significant PCa (29% vs 32%; p=0.7) and the highest percentage tumor involvement per biopsy core (48% vs 42%; p=0.4) were similar between the arms. The mean number of cores was 5.6 versus 17 (p<0.001). A limitation is the limited number of patients because of early cessation of accrual. This trial failed to identify an important improvement in detection rate for the combined biopsy approach over MRI-targeted biopsy alone. A prospective comparison between MRI-targeted biopsy alone and systematic TRUS-GB is justified. Our randomized study showed similar prostate cancer detection rates between targeted prostate biopsy guided by magnetic resonance imaging and the combination of targeted biopsy and systematic transrectal ultrasound-guided prostate biopsy. An important improvement in detection rates using the combined biopsy approach can be excluded. Copyright © 2015 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Allergy and parasites reevaluated: wide-scale induction of chronic urticaria by the ubiquitous fish-nematode Anisakis simplex in an endemic region.

PubMed

Daschner, A; Vega de la Osada, F; Pascual, C Y

2005-01-01

The ubiquitous fish-nematode Anisakis simplex produces acute urticaria or angioedema in the course of gastro-allergic anisakiasis. We studied the relationship between this nematode and chronic urticaria (CU), as well as the clinical usefulness of measuring specific IgG4 in A. simplex-sensitized patients with CU. First, the prevalence of sensitization to A. simplex was estimated in 135 consecutive CU patients and the result was compared with known data about sensitization in a healthy population. Then, clinical response to a 2-month diet without fish was analyzed in 76 CU patients. The improvement rate in patients with and without sensitization to A. simplex was compared. Finally, the improvement rate, other clinical data and specific immunoglobulins in sensitized patients with and without detectable specific IgG4 were compared. a) The A. simplex sensitization rate in CU patients was 52.6 % compared with a known prevalence of between 16 and 20 % in our region. b) Of 65 sensitized patients, 52 experienced clinical improvement after the diet compared with only three of 11 patients without sensitization to A. simplex (p = 0.001). c) Of 43 patients with detectable specific IgG4, 38 showed clinical improvement compared with only 14 of 22 patients without detectable IgG4 (p = 0.02). Eight of nine patients with previous fish-associated cutaneous symptoms had detectable specific IgG4 compared with 15 of 32 patients who reported no previous fish-associated symptoms or acute urticaria (p = 0.03). Our results indicate that A. simplex is a possibly widespread etiologic agent able to induce CU. This parasite model constitutes the first report that associates an infectious agent with CU on a large scale. The detection of IgG4 antibodies reflects a previous acute parasitic infection and a temporary diet without fish improves symptoms in most patients with detectable specific IgG4.

Non-invasive prenatal screening versus prenatal diagnosis by array comparative genomic hybridization: a comparative retrospective study.

PubMed

Sotiriadis, Alexandros; Papoulidis, Ioannis; Siomou, Elisavet; Papageorgiou, Elena; Eleftheriades, Makarios; Papadopoulos, Vasilios; Alexiou, Maria; Manolakos, Emmanouil; Athanasiadis, Apostolos

2017-06-01

To calculate the proportion of array comparative genomic hybridization (aCGH) pathogenic results, that would not be detectable by non-invasive prenatal screening (NIPS). This is a comparative study using data from 2779 fetuses, which underwent invasive prenatal diagnosis, and the samples were analyzed using aCGH. The simulated NIPS assay would test for trisomies 21, 18, 13, monosomy X, 47, XXX, 47, XYY, and 47, XXY. Indications for invasive testing were grouped into categories and the absolute, relative rates of pathogenic/likely pathogenic results of aCGH analysis that would not be detectable by NIPS were calculated. The expected rate of aCGH-detected abnormalities that would not be detectable by NIPS was 28.0% (95% CI 14.3-47.6) for nuchal translucency (NT) 95 to 99th centile; 14.3% (95% 5.0-34.6) for NT > 99th centile; 34.2% (95% CI 21.1-50.1) for high-risk first-trimester results (regardless of NT); 52.4% (95% CI 32.4-71.7) for second-trimester markers; and 50.0% (95% CI 26.8-73.2) for advanced maternal age. The overall rate of aCGH pathogenic/likely pathogenic results was 5.0% and 44.0% (95% CI 36.0-52.2) of them would not be detected by NIPS. Approximately half of the abnormal aCGH results would not be detectable by standard NIPS assays, highlighting the necessity of pre-test counseling, and illustrating the limitations of NIPS. © 2017 John Wiley & Sons, Ltd. © 2017 John Wiley & Sons, Ltd.

Detection limit for rate fluctuations in inhomogeneous Poisson processes

NASA Astrophysics Data System (ADS)

Shintani, Toshiaki; Shinomoto, Shigeru

2012-04-01

Estimations of an underlying rate from data points are inevitably disturbed by the irregular occurrence of events. Proper estimation methods are designed to avoid overfitting by discounting the irregular occurrence of data, and to determine a constant rate from irregular data derived from a constant probability distribution. However, it can occur that rapid or small fluctuations in the underlying density are undetectable when the data are sparse. For an estimation method, the maximum degree of undetectable rate fluctuations is uniquely determined as a phase transition, when considering an infinitely long series of events drawn from a fluctuating density. In this study, we analytically examine an optimized histogram and a Bayesian rate estimator with respect to their detectability of rate fluctuation, and determine whether their detectable-undetectable phase transition points are given by an identical formula defining a degree of fluctuation in an underlying rate. In addition, we numerically examine the variational Bayes hidden Markov model in its detectability of rate fluctuation, and determine whether the numerically obtained transition point is comparable to those of the other two methods. Such consistency among these three principled methods suggests the presence of a theoretical limit for detecting rate fluctuations.

Detection limit for rate fluctuations in inhomogeneous Poisson processes.

PubMed

Shintani, Toshiaki; Shinomoto, Shigeru

2012-04-01

Estimations of an underlying rate from data points are inevitably disturbed by the irregular occurrence of events. Proper estimation methods are designed to avoid overfitting by discounting the irregular occurrence of data, and to determine a constant rate from irregular data derived from a constant probability distribution. However, it can occur that rapid or small fluctuations in the underlying density are undetectable when the data are sparse. For an estimation method, the maximum degree of undetectable rate fluctuations is uniquely determined as a phase transition, when considering an infinitely long series of events drawn from a fluctuating density. In this study, we analytically examine an optimized histogram and a Bayesian rate estimator with respect to their detectability of rate fluctuation, and determine whether their detectable-undetectable phase transition points are given by an identical formula defining a degree of fluctuation in an underlying rate. In addition, we numerically examine the variational Bayes hidden Markov model in its detectability of rate fluctuation, and determine whether the numerically obtained transition point is comparable to those of the other two methods. Such consistency among these three principled methods suggests the presence of a theoretical limit for detecting rate fluctuations.

Effect of age on breast cancer screening using tomosynthesis in combination with digital mammography.

PubMed

Rafferty, Elizabeth A; Rose, Stephen L; Miller, Dave P; Durand, Melissa A; Conant, Emily F; Copit, Debra S; Friedewald, Sarah M; Plecha, Donna M; Ott, Ingrid L; Hayes, Mary K; Carlson, Kara L; Cink, Thomas M; Barke, Lora D; Greer, Linda N; Niklason, Loren T

2017-08-01

To determine the effect of tomosynthesis imaging as a function of age for breast cancer screening. Screening performance metrics from 13 institutions were examined for 12 months prior to introduction of tomosynthesis (period 1) and compared to those after introduction of tomosynthesis (period 2, range 3-22 months). Screening metrics for women ages 40-49, 50-59, 60-69, and 70+ , included rates per 1000 screens for recalls, biopsies, cancers, and invasive cancers detected. Performance parameters were compared for women screened with digital mammography alone (n = 278,908) and digital mammography + tomosynthesis (n = 173,414). Addition of tomosynthesis to digital mammography produced significant reductions in recall rates for all age groups and significant increases in cancer detection rates for women 40-69. Largest recall rate reduction with tomosynthesis was for women 40-49, decreasing from 137 (95% CI 117-156) to 115 (95% CI 95-135); difference, -22 (95% CI -26 to -18; P < .001). Simultaneous increase in invasive cancer detection rate for women 40-49 from 1.6 (95% CI 1.2-1.9) to 2.7 (95% CI 2.2-3.1) with tomosynthesis (difference, 1.1; 95% CI 0.6-1.6; P < .001) was observed. Addition of tomosynthesis to digital mammography increased invasive cancer detection rates for women 40-69 and decreased recall rates for all age groups with largest performance gains seen in women 40-49. The similar performance seen with tomosynthesis screening for women in their 40s compared to digital mammography for women in their 50s argues strongly for commencement of mammography screening at age 40 using tomosynthesis.

Assessing the role of spectral and intensity cues in spectral ripple detection and discrimination in cochlear-implant users

PubMed Central

Anderson, Elizabeth S.; Oxenham, Andrew J.; Nelson, Peggy B.; Nelson, David A.

2012-01-01

Measures of spectral ripple resolution have become widely used psychophysical tools for assessing spectral resolution in cochlear-implant (CI) listeners. The objective of this study was to compare spectral ripple discrimination and detection in the same group of CI listeners. Ripple detection thresholds were measured over a range of ripple frequencies and were compared to spectral ripple discrimination thresholds previously obtained from the same CI listeners. The data showed that performance on the two measures was correlated, but that individual subjects’ thresholds (at a constant spectral modulation depth) for the two tasks were not equivalent. In addition, spectral ripple detection was often found to be possible at higher rates than expected based on the available spectral cues, making it likely that temporal-envelope cues played a role at higher ripple rates. Finally, spectral ripple detection thresholds were compared to previously obtained speech-perception measures. Results confirmed earlier reports of a robust relationship between detection of widely spaced ripples and measures of speech recognition. In contrast, intensity difference limens for broadband noise did not correlate with spectral ripple detection measures, suggesting a dissociation between the ability to detect small changes in intensity across frequency and across time. PMID:23231122

Detection rates of the MODIS active fire product in the United States

USGS Publications Warehouse

Hawbaker, T.J.; Radeloff, V.C.; Syphard, A.D.; Zhu, Z.; Stewart, S.I.

2008-01-01

MODIS active fire data offer new information about global fire patterns. However, uncertainties in detection rates can render satellite-derived fire statistics difficult to interpret. We evaluated the MODIS 1??km daily active fire product to quantify detection rates for both Terra and Aqua MODIS sensors, examined how cloud cover and fire size affected detection rates, and estimated how detection rates varied across the United States. MODIS active fire detections were compared to 361 reference fires (??? 18??ha) that had been delineated using pre- and post-fire Landsat imagery. Reference fires were considered detected if at least one MODIS active fire pixel occurred within 1??km of the edge of the fire. When active fire data from both Aqua and Terra were combined, 82% of all reference fires were found, but detection rates were less for Aqua and Terra individually (73% and 66% respectively). Fires not detected generally had more cloudy days, but not when the Aqua data were considered exclusively. MODIS detection rates decreased with fire size, and the size at which 50% of all fires were detected was 105??ha when combining Aqua and Terra (195??ha for Aqua and 334??ha for Terra alone). Across the United States, detection rates were greatest in the West, lower in the Great Plains, and lowest in the East. The MODIS active fire product captures large fires in the U.S. well, but may under-represent fires in areas with frequent cloud cover or rapidly burning, small, and low-intensity fires. We recommend that users of the MODIS active fire data perform individual validations to ensure that all relevant fires are included. ?? 2008 Elsevier Inc. All rights reserved.

Impact of time-of-flight PET on quantification accuracy and lesion detection in simultaneous 18F-choline PET/MRI for prostate cancer.

PubMed

Mühlematter, Urs J; Nagel, Hannes W; Becker, Anton; Mueller, Julian; Vokinger, Kerstin N; de Galiza Barbosa, Felipe; Ter Voert, Edwin E G T; Veit-Haibach, Patrick; Burger, Irene A

2018-05-31

Accurate attenuation correction (AC) is an inherent problem of positron emission tomography magnetic resonance imaging (PET/MRI) systems. Simulation studies showed that time-of-flight (TOF) detectors can reduce PET quantification errors in MRI-based AC. However, its impact on lesion detection in a clinical setting with 18 F-choline has not yet been evaluated. Therefore, we compared TOF and non-TOF 18 F-choline PET for absolute and relative difference in standard uptake values (SUV) and investigated the detection rate of metastases in prostate cancer patients. Non-TOF SUV was significantly lower compared to TOF in all osseous structures, except the skull, in primary lesions of the prostate, and in pelvic nodal and osseous metastasis. Concerning lymph node metastases, both experienced readers detected 16/19 (84%) on TOF PET, whereas on non-TOF PET readers 1 and 2 detected 11 (58%), and 14 (73%), respectively. With TOF PET readers 1 and 2 detected 14/15 (93%) and 11/15 (73%) bone metastases, respectively, whereas detection rate with non-TOF PET was 73% (11/15) for reader 1 and 53% (8/15) for reader 2. The interreader agreement was good for osseous metastasis detection on TOF (kappa 0.636, 95% confidence interval [CI] 0.453-0.810) and moderate on non-TOF (kappa = 0.600, CI 0.438-0.780). TOF reconstruction for 18 F-choline PET/MRI shows higher SUV measurements compared to non-TOF reconstructions in physiological osseous structures as well as pelvic malignancies. Our results suggest that addition of TOF information has a positive impact on lesion detection rate for lymph node and bone metastasis in prostate cancer patients.

Comparing Automatic CME Detections in Multiple LASCO and SECCHI Catalogs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hess, Phillip; Colaninno, Robin C., E-mail: phillip.hess.ctr@nrl.navy.mil, E-mail: robin.colaninno@nrl.navy.mil

With the creation of numerous automatic detection algorithms, a number of different catalogs of coronal mass ejections (CMEs) spanning the entirety of the Solar and Heliospheric Observatory ( SOHO ) Large Angle Spectrometric Coronagraph (LASCO) mission have been created. Some of these catalogs have been further expanded for use on data from the Solar Terrestrial Earth Observatory ( STEREO ) Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI) as well. We compare the results from different automatic detection catalogs (Solar Eruption Event Detection System (SEEDS), Computer Aided CME Tracking (CACTus), and Coronal Image Processing (CORIMP)) to ensure the consistency ofmore » detections in each. Over the entire span of the LASCO catalogs, the automatic catalogs are well correlated with one another, to a level greater than 0.88. Focusing on just periods of higher activity, these correlations remain above 0.7. We establish the difficulty in comparing detections over the course of LASCO observations due to the change in the instrument image cadence in 2010. Without adjusting catalogs for the cadence, CME detection rates show a large spike in cycle 24, despite a notable drop in other indices of solar activity. The output from SEEDS, using a consistent image cadence, shows that the CME rate has not significantly changed relative to sunspot number in cycle 24. These data, and mass calculations from CORIMP, lead us to conclude that any apparent increase in CME rate is a result of the change in cadence. We study detection characteristics of CMEs, discussing potential physical changes in events between cycles 23 and 24. We establish that, for detected CMEs, physical parameters can also be sensitive to the cadence.« less

A comparative study of FDG PET/CT and enhanced multi-detector CT for detecting liver metastasis according to the size and location.

PubMed

Park, Jung Mi; Kim, Il Young; Kim, Sang Won; Lee, Sang Mi; Kim, Hyun Gi; Kim, Shin Young; Shin, Hyung Chul

2013-04-01

The aim of this study was to compare the diagnosability between (18)F-fluorodeoxyglucose (FDG) PET/CT and enhanced multi-detector CT (MDCT) for the detection of liver metastasis (LM) according to the size and location in liver and to evaluate standard maximum standardized uptake values (SUVmax) of all liver metastatic lesions. One hundred two consecutive patients with malignancy who underwent both FDG PET/CT and MDCT for LM evaluation were retrospectively reviewed. Among them, 56 patients with LM were enrolled in this study. LM was confirmed by follow-up imaging studies after at least 6 months or by histopathology. FDG PET/CT and MDCT images were visually analyzed using three-point scale by the consensus of two radiologists and two nuclear medicine physicians. The size and location (central vs. sub-capsular) of the all liver lesions were evaluated using MDCT images. Furthermore, SUVmax of all liver lesions on FDG PET/CT images were calculated. A total of 146 liver lesions were detected by FDG PET/CT and MDCT and 142 of the lesions were diagnosed as LM. The detection rates of MDCT and FDG PET/CT for LM by visual analysis were 77 and 78%, respectively. There was no significant difference of detection rate according to the overall location and size of the lesions. However, FDG PET/CT was more sensitive than MDCT for detecting small and sub-capsular LM. The detection rate of FDG PET/CT for LM was 68% by the cutoff SUVmax of 2.7. Although the diagnosabilities of MDCT and FDG PET/CT for detecting LM were comparable, FDG PET/CT is superior to MDCT for detecting small LM located in the sub-capsular portion of liver.

Evaluation of machine learning algorithms for improved risk assessment for Down's syndrome.

PubMed

Koivu, Aki; Korpimäki, Teemu; Kivelä, Petri; Pahikkala, Tapio; Sairanen, Mikko

2018-05-04

Prenatal screening generates a great amount of data that is used for predicting risk of various disorders. Prenatal risk assessment is based on multiple clinical variables and overall performance is defined by how well the risk algorithm is optimized for the population in question. This article evaluates machine learning algorithms to improve performance of first trimester screening of Down syndrome. Machine learning algorithms pose an adaptive alternative to develop better risk assessment models using the existing clinical variables. Two real-world data sets were used to experiment with multiple classification algorithms. Implemented models were tested with a third, real-world, data set and performance was compared to a predicate method, a commercial risk assessment software. Best performing deep neural network model gave an area under the curve of 0.96 and detection rate of 78% with 1% false positive rate with the test data. Support vector machine model gave area under the curve of 0.95 and detection rate of 61% with 1% false positive rate with the same test data. When compared with the predicate method, the best support vector machine model was slightly inferior, but an optimized deep neural network model was able to give higher detection rates with same false positive rate or similar detection rate but with markedly lower false positive rate. This finding could further improve the first trimester screening for Down syndrome, by using existing clinical variables and a large training data derived from a specific population. Copyright © 2018 Elsevier Ltd. All rights reserved.

Superior Rhythm Discrimination With the SmartShock Technology Algorithm　- Results of the Implantable Defibrillator With Enhanced Features and Settings for Reduction of Inaccurate Detection (DEFENSE) Trial.

PubMed

Oginosawa, Yasushi; Kohno, Ritsuko; Honda, Toshihiro; Kikuchi, Kan; Nozoe, Masatsugu; Uchida, Takayuki; Minamiguchi, Hitoshi; Sonoda, Koichiro; Ogawa, Masahiro; Ideguchi, Takeshi; Kizaki, Yoshihisa; Nakamura, Toshihiro; Oba, Kageyuki; Higa, Satoshi; Yoshida, Keiki; Tsunoda, Soichi; Fujino, Yoshihisa; Abe, Haruhiko

2017-08-25

Shocks delivered by implanted anti-tachyarrhythmia devices, even when appropriate, lower the quality of life and survival. The new SmartShock Technology ® (SST) discrimination algorithm was developed to prevent the delivery of inappropriate shock. This prospective, multicenter, observational study compared the rate of inaccurate detection of ventricular tachyarrhythmia using the SST vs. a conventional discrimination algorithm.Methods and Results:Recipients of implantable cardioverter defibrillators (ICD) or cardiac resynchronization therapy defibrillators (CRT-D) equipped with the SST algorithm were enrolled and followed up every 6 months. The tachycardia detection rate was set at ≥150 beats/min with the SST algorithm. The primary endpoint was the time to first inaccurate detection of ventricular tachycardia (VT) with conventional vs. the SST discrimination algorithm, up to 2 years of follow-up. Between March 2012 and September 2013, 185 patients (mean age, 64.0±14.9 years; men, 74%; secondary prevention indication, 49.5%) were enrolled at 14 Japanese medical centers. Inaccurate detection was observed in 32 patients (17.6%) with the conventional, vs. in 19 patients (10.4%) with the SST algorithm. SST significantly lowered the rate of inaccurate detection by dual chamber devices (HR, 0.50; 95% CI: 0.263-0.950; P=0.034). Compared with previous algorithms, the SST discrimination algorithm significantly lowered the rate of inaccurate detection of VT in recipients of dual-chamber ICD or CRT-D.

Radiation dose-rate meter using an energy-sensitive counter

DOEpatents

Kopp, Manfred K.

1988-01-01

A radiation dose-rate meter is provided which uses an energy-sensitive detector and combines charge quantization and pulse-rate measurement to monitor radiation dose rates. The charge from each detected photon is quantized by level-sensitive comparators so that the resulting total output pulse rate is proportional to the dose-rate.

High resolution colonoscopy in a bowel cancer screening program improves polyp detection

PubMed Central

Banks, Matthew R; Haidry, Rehan; Butt, M Adil; Whitley, Lisa; Stein, Judith; Langmead, Louise; Bloom, Stuart L; O’Bichere, Austin; McCartney, Sara; Basherdas, Kalpesh; Rodriguez-Justo, Manuel; Lovat, Laurence B

2011-01-01

AIM: To compare high resolution colonoscopy (Olympus Lucera) with a megapixel high resolution system (Pentax HiLine) as an in-service evaluation. METHODS: Polyp detection rates and measures of performance were collected for 269 colonoscopy procedures. Five colonoscopists conducted the study over a three month period, as part of the United Kingdom bowel cancer screening program. RESULTS:There were no differences in procedure duration (χ2 P = 0.98), caecal intubation rates (χ2 P = 0.67), or depth of sedation (χ2 P = 0.64). Mild discomfort was more common in the Pentax group (χ2 P = 0.036). Adenoma detection rate was significantly higher in the Pentax group (χ2 test for trend P = 0.01). Most of the extra polyps detected were flat or sessile adenomas. CONCLUSION: Megapixel definition colonoscopes improve adenoma detection without compromising other measures of endoscope performance. Increased polyp detection rates may improve future outcomes in bowel cancer screening programs. PMID:22090787

Comparison of Detection Rate and Mutational Pattern of Drug-Resistant Mutations Between a Large Cohort of Genotype B and Genotype C Hepatitis B Virus-Infected Patients in North China.

PubMed

Li, Xiaodong; Liu, Yan; Xin, Shaojie; Ji, Dong; You, Shaoli; Hu, Jinhua; Zhao, Jun; Wu, Jingjing; Liao, Hao; Zhang, Xin-Xin; Xu, Dongping

2017-06-01

The study aimed to investigate the association of prevalent genotypes in China (HBV/C and HBV/B) with HBV drug-resistant mutations. A total of 13,847 nucleos(t)ide analogue (NA)-treated patients with chronic HBV infection from North China were enrolled. HBV genotypes and resistant mutations were determined by direct sequencing and confirmed by clonal sequencing if necessary. HBV/B, HBV/C, and HBV/D occupied 14.3%, 84.9%, and 0.8% across the study population, respectively. NA usage had no significant difference between HBV/B- and HBV/C-infected patients. Lamivudine-resistant mutations were more frequently detected in HBV/C-infected patients, compared with HBV/B-infected patients (31.67% vs. 25.26%, p < 0.01). Adefovir- and entecavir-resistant mutation detection rates were similar, but the mutational pattern was different between the two genotypes. For adefovir-resistant mutations, HBV/C-infected patients had a higher detection rate of rtA181 V (HBV/C 5.29% vs. HBV/B 1.36%, p < 0.01) and a lower detection rate of rtN236T (2.70% vs. 6.54%, p < 0.01). For entecavir-resistant mutations, HBV/C-infected patients had a higher detection rate of rtM204 V/I+T184 substitution or S202G/C (3.66% vs. 2.16%, p < 0.01) and a lower detection rate of rtM204 V/I+M250 V/I/L substitution (0.67% vs. 1.46%, p < 0.01). Multidrug-resistant mutations (defined as coexistence of mutation to nucleoside and nucleotide analogues) were detected in 104 patients. HBV/C-infected patients had a higher detection rate of multidrug-resistant mutation than HBV/B-infected patients (0.83% vs. 0.35%, p < 0.05). The study for the first time clarified that HBV/C-infected patients had a higher risk to develop multidrug-resistant mutations, compared with HBV/B-infected patients; and HBV/C- and HBV/B-infected patients had different inclinations in the ETV-resistant mutational pattern.

Transrectal real-time tissue elastography targeted biopsy coupled with peak strain index improves the detection of clinically important prostate cancer.

PubMed

Ma, Qi; Yang, Dong-Rong; Xue, Bo-Xin; Wang, Cheng; Chen, Han-Bin; Dong, Yun; Wang, Cai-Shan; Shan, Yu-Xi

2017-07-01

The focus of the present study was to evaluate transrectal real-time tissue elastography (RTE)-targeted two-core biopsy coupled with peak strain index for the detection of prostate cancer (PCa) and to compare this method with 10-core systematic biopsy. A total of 141 patients were enrolled for evaluation. The diagnostic value of peak strain index was assessed using a receiver operating characteristic curve. The cancer detection rates of the two approaches and corresponding positive cores and Gleason score were compared. The cancer detection rate per core in the RTE-targeted biopsy (44%) was higher compared with that in systematic biopsy (30%). The peak strain index value of PCa was higher compared with that of the benign lesion. PCa was detected with the highest sensitivity (87.5%) and specificity (85.5%) using the threshold value of a peak strain index of ≥5.97 with an area under the curve value of 0.95. When the Gleason score was ≥7, RTE-targeted biopsy coupled with peak strain index detected 95.6% of PCa cases, but 84.4% were detected using systematic biopsy. Peak strain index as a quantitative parameter may improve the differentiation of PCa from benign lesions in the prostate peripheral zone. Transrectal RTE-targeted biopsy coupled with peak strain index may enhance the detection of clinically significant PCa, particularly when combined with systematic biopsy.

Comparing the Rates of Retinal Nerve Fiber Layer and Ganglion Cell-Inner Plexiform Layer Loss in Healthy Eyes and in Glaucoma Eyes.

PubMed

Hammel, Naama; Belghith, Akram; Weinreb, Robert N; Medeiros, Felipe A; Mendoza, Nadia; Zangwill, Linda M

2017-06-01

To compare the rates of circumpapillary retinal nerve fiber layer (RNFL) and macular retinal ganglion cell-inner plexiform layer (GCIPL) change over time in healthy and glaucoma eyes. Cohort study. The rates of circumpapillary RNFL and macular GCIPL loss in 28 healthy subjects and 97 glaucoma subjects from the Diagnostic Innovations in Glaucoma Study (DIGS) were compared using mixed-effects models. The median follow-up time and number of visits were 1.7 years and 6 visits and 3.2 years and 7 visits for healthy and glaucoma eyes, respectively. Significant rates of loss of both global circumpapillary RNFL and average macular GCIPL thickness were detectable in early and moderate glaucoma eyes; in severe glaucoma eyes, rates of average macular GCIPL loss were significant, but rates of global circumpapillary RNFL loss were not. In glaucoma eyes, mean rates of global circumpapillary RNFL thickness change (-0.98 μm/year [95% confidence interval (CI), -1.20 to -0.76]) and normalized global circumpapillary RNFL change (-1.7%/year [95% CI, -2.1 to -1.3]) were significantly faster than average macular GCIPL change (-0.57 μm/year [(95% CI, -0.73 to -0.41]) and normalized macular GCIPL change (-1.3%/year [95% CI, -1.7 to -0.9]). The rates of global and inferior RNFL change were weakly correlated with global and inferior macular GCIPL change (r ranges from 0.16 to 0.23, all P < .05). In this cohort, the rate of circumpapillary RNFL thickness change was faster than macular GCIPL change for glaucoma eyes. Global circumpapillary RNFL thickness loss was detectable in early and moderate glaucoma, and average macular GCIPL thickness loss was detectable in early, moderate, and severe glaucoma, suggesting that structural changes can be detected in severe glaucoma. Copyright © 2017 Elsevier Inc. All rights reserved.

Multi-modal automatic montaging of adaptive optics retinal images

PubMed Central

Chen, Min; Cooper, Robert F.; Han, Grace K.; Gee, James; Brainard, David H.; Morgan, Jessica I. W.

2016-01-01

We present a fully automated adaptive optics (AO) retinal image montaging algorithm using classic scale invariant feature transform with random sample consensus for outlier removal. Our approach is capable of using information from multiple AO modalities (confocal, split detection, and dark field) and can accurately detect discontinuities in the montage. The algorithm output is compared to manual montaging by evaluating the similarity of the overlapping regions after montaging, and calculating the detection rate of discontinuities in the montage. Our results show that the proposed algorithm has high alignment accuracy and a discontinuity detection rate that is comparable (and often superior) to manual montaging. In addition, we analyze and show the benefits of using multiple modalities in the montaging process. We provide the algorithm presented in this paper as open-source and freely available to download. PMID:28018714

Trimodal endoscopic imaging for the detection and differentiation of colorectal adenomas: a prospective single-centre clinical evaluation.

PubMed

Rotondano, Gianluca; Bianco, Maria Antonia; Sansone, Stefano; Prisco, Antonio; Meucci, Costantino; Garofano, Maria Lucia; Cipolletta, Livio

2012-03-01

The purpose of this study is to evaluate an endoscopic trimodal imaging (ETMI) system (high resolution, autofluorescence, and NBI) in the detection and differentiation of colorectal adenomas. A prospective randomised trial of tandem colonoscopies was carried out using the Olympus XCF-FH260AZI system. Each colonic segment was examined twice for lesions, once with HRE and once with AFI, in random order per patient. All detected lesions were assessed with NBI for pit pattern and with AFI for colour. All lesions were removed and sent for histology. Any lesion identified on the second examination was considered as missed by the first examination. Outcome measures are adenoma miss rates of AFI and HRE, and diagnostic accuracy of NBI and AFI for differentiating neoplastic from non-neoplastic lesions. Ninety-four patients underwent colonoscopy with ETMI (47 in each group). Among 47 patients examined with AFI first, 31 adenomas in 15 patients were detected initially [detection rate 0.66 (0.52-0.75)]. Subsequent HRE inspection identified six additional adenomas. Among 47 patients examined with HRE first, 29 adenomas in 14 patients were detected initially [detection rate 0.62 (0.53-0.79)]. Successive AFI yielded seven additional adenomas. Adenoma miss rates of AFI and HRE were 14% and 16.2%, respectively (p = 0.29). Accuracy of AFI alone for differentiation was lower than NBI (63% vs. 80%, p < 0.001). Combined use of AFI and NBI achieved improved accuracy for differentiation (84%), showing a trend for superiority compared with NBI alone (p = 0.064). AFI did not significantly reduce the adenoma miss rate compared with HRE. AFI alone had a disappointing accuracy for adenoma differentiation, which could be improved by combination of AFI and NBI.

Fetuses with Down's Syndrome detected by prenatal screening are more likely to abort spontaneously than fetuses with Down's Syndrome not detected by prenatal screening.

PubMed

Leporrier, Nathalie; Herrou, Michel; Morello, Rémy; Leymarie, Pierre

2003-01-01

Pregnancy with Down's Syndrome is often terminated by miscarriage. We have investigated whether prenatal screening would lead preferentially to the identification of fetuses with Down's Syndrome prone to abort spontaneously. A comparison between the observed and the expected decrease in the prevalence of Down's Syndrome at term following extensive prenatal screening. A study from 1990 to 1998 in a limited and well controlled area of western France (Basse Normandie), with a birth rate close to 20,000 a year. Women under 38 years of age among whom prenatal screening for Down's Syndrome using biochemical tests and ultrasound findings became progressively extensive in this era. Our study was based on the registration of Down's Syndrome cases detected prenatally from screening, and live births with Down's Syndrome. Fetal loss rate in the population of prenatally detectable Down's Syndrome was evaluated by comparing the increase in detection of cases of Down's Syndrome following prenatal screening with the expected decrease in the number of cases of Down's Syndrome at birth. The results obtained were compared with published data on the rates of fetal losses postulated to occur among fetuses with Down's Syndrome. Comparison of the potential fetal loss rate in a population in whom Down's Syndrome was detected prenatally with the expected fetal loss rate of unselected ones. Prenatal screening resulted in a significant (42%) decrease (P < 0.001) in the prevalence at term of the disorder. Among the 53 fetuses with Down's Syndrome detected prenatally during the last three years of the study, about 50% would have aborted spontaneously if the pregnancy had been allowed to continue. This figure was significantly higher (P < 0.002) than expected on the basis of results from the literature, indicating that current estimates of miscarriage rates among fetuses with Down's Syndrome do not apply to the selected group of cases detectable from prenatal screening. Our results suggest that fetuses with Down's Syndrome detectable prenatally from screening are more likely to abort spontaneously than fetuses with Down's Syndrome which are not detected.

Blood pressure cuffs as a vector for transmission of multi-resistant organisms: colonisation rates and effects of disinfection.

PubMed

Grewal, Harjeet; Varshney, Kavita; Thomas, Lee C; Kok, Jen; Shetty, Amith

2013-06-01

Blood pressure (BP) cuffs are potential vectors for transmission of multi-resistant organisms (MROs). The present study aims to determine MRO colonisation rates in BP cuffs from areas of high patient flow as an assessment of the quality of disinfection and infection control practices. BP cuffs in the ED, high dependency unit (HDU) and operating theatres (OT) were prospectively examined after routine disinfection procedures. Swabs collected from the inner and outer surfaces of BP cuffs during inter-patient intervals were plated onto replicate organism detection and counting, methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) chromogenic agar plates to detect rates of bacterial, MRSA and VRE colonisation, respectively. High bacterial colonisation rates were detected in BP cuffs from all three areas. BP cuffs from OT were significantly less colonised compared with cuffs from HDU and ED; 76% versus 96% and 100% (P < 0.0001) for inner surfaces and 86% versus 98% and 100% (P < 0.0001) for outer surfaces, respectively. Equivalent or higher bacterial growth was observed on the inner surface compared with outer surface in 54%, 84% and 86% of BP cuffs from OT, HDU and ED, respectively. MRSA was detected in 3 of 150 (2%) swabs collected, but no VRE was detected. Although MRSA and VRE were infrequently isolated, current disinfection and infection control protocols need to be improved given the greater recovery of organisms from the inner compared with outer surfaces of BP cuffs. © 2013 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

A likelihood ratio test for evolutionary rate shifts and functional divergence among proteins

PubMed Central

Knudsen, Bjarne; Miyamoto, Michael M.

2001-01-01

Changes in protein function can lead to changes in the selection acting on specific residues. This can often be detected as evolutionary rate changes at the sites in question. A maximum-likelihood method for detecting evolutionary rate shifts at specific protein positions is presented. The method determines significance values of the rate differences to give a sound statistical foundation for the conclusions drawn from the analyses. A statistical test for detecting slowly evolving sites is also described. The methods are applied to a set of Myc proteins for the identification of both conserved sites and those with changing evolutionary rates. Those positions with conserved and changing rates are related to the structures and functions of their proteins. The results are compared with an earlier Bayesian method, thereby highlighting the advantages of the new likelihood ratio tests. PMID:11734650

Estimating site occupancy rates for aquatic plants using spatial sub-sampling designs when detection probabilities are less than one

USGS Publications Warehouse

Nielson, Ryan M.; Gray, Brian R.; McDonald, Lyman L.; Heglund, Patricia J.

2011-01-01

Estimation of site occupancy rates when detection probabilities are <1 is well established in wildlife science. Data from multiple visits to a sample of sites are used to estimate detection probabilities and the proportion of sites occupied by focal species. In this article we describe how site occupancy methods can be applied to estimate occupancy rates of plants and other sessile organisms. We illustrate this approach and the pitfalls of ignoring incomplete detection using spatial data for 2 aquatic vascular plants collected under the Upper Mississippi River's Long Term Resource Monitoring Program (LTRMP). Site occupancy models considered include: a naïve model that ignores incomplete detection, a simple site occupancy model assuming a constant occupancy rate and a constant probability of detection across sites, several models that allow site occupancy rates and probabilities of detection to vary with habitat characteristics, and mixture models that allow for unexplained variation in detection probabilities. We used information theoretic methods to rank competing models and bootstrapping to evaluate the goodness-of-fit of the final models. Results of our analysis confirm that ignoring incomplete detection can result in biased estimates of occupancy rates. Estimates of site occupancy rates for 2 aquatic plant species were 19–36% higher compared to naive estimates that ignored probabilities of detection <1. Simulations indicate that final models have little bias when 50 or more sites are sampled, and little gains in precision could be expected for sample sizes >300. We recommend applying site occupancy methods for monitoring presence of aquatic species.

Evaluating autonomous acoustic surveying techniques for rails in tidal marshes

USGS Publications Warehouse

Stiffler, Lydia L.; Anderson, James T.; Katzner, Todd

2018-01-01

There is a growing interest toward the use of autonomous recording units (ARUs) for acoustic surveying of secretive marsh bird populations. However, there is little information on how ARUs compare to human surveyors or how best to use ARU data that can be collected continuously throughout the day. We used ARUs to conduct 2 acoustic surveys for king (Rallus elegans) and clapper rails (R. crepitans) within a tidal marsh complex along the Pamunkey River, Virginia, USA, during May–July 2015. To determine the effectiveness of an ARU in replacing human personnel, we compared results of callback point‐count surveys with concurrent acoustic recordings and calculated estimates of detection probability for both rail species combined. The success of ARUs at detecting rails that human observers recorded decreased with distance (P ≤ 0.001), such that at <25 m, 90.3% of human‐recorded rails also were detected by the ARU, but at >75 m, only 34.0% of human‐detected rails were detected by the ARU. To determine a subsampling scheme for continuous ARU data that allows for effective surveying of presence and call rates of rails, we used ARUs to conduct 15 continuous 48‐hr passive surveys, generating 720 hr of recordings. We established 5 subsampling periods of 5, 10, 15, 30, and 45 min to evaluate ARU‐based presence and vocalization detections of rails compared with each of the full 60‐min sampling of ARU‐based detection of rails. All subsampling periods resulted in different (P ≤ 0.001) detection rates and unstandardized vocalization rates compared with the hourly sampling period. However, standardized vocalization counts from the 30‐min subsampling period were not different from vocalization counts of the full hourly sampling period. When surveying rail species in estuarine environments, species‐, habitat‐, and ARU‐specific limitations to ARU sampling should be considered when making inferences about abundances and distributions from ARU data. 

Population-based mammography screening: comparison of screen-film and full-field digital mammography with soft-copy reading--Oslo I study.

PubMed

Skaane, Per; Young, Kari; Skjennald, Arnulf

2003-12-01

To compare screen-film and full-field digital mammography with soft-copy reading in a population-based screening program. Full-field digital and screen-film mammography were performed in 3,683 women aged 50-69 years. Two standard views of each breast were acquired with each modality. Images underwent independent double reading with use of a five-point rating scale for probability of cancer. Recall rates and positive predictive values were calculated. Cancer detection rates determined with both modalities were compared by using the McNemar test for paired proportions. Retrospective side-by-side analysis for conspicuity of cancers was performed by an external independent radiologist group with experience in both modalities. In 3,683 cases, 31 cancers were detected. Screen-film mammography depicted 28 (0.76%) malignancies, and full-field digital mammography depicted 23 (0.62%) malignancies. The difference between cancer detection rates was not significant (P =.23). The recall rate for full-field digital mammography (4.6%; 168 of 3,683 cases) was slightly higher than that for screen-film mammography (3.5%; 128 of 3,683 cases). The positive predictive value based on needle biopsy results was 46% for screen-film mammography and 39% for full-field digital mammography. Side-by-side image comparison for cancer conspicuity led to classification of 19 cancers as equal for probability of malignancy, six cancers as slightly better demonstrated at screen-film mammography, and six cancers as slightly better demonstrated at full-field digital mammography. There was no statistically significant difference in cancer detection rate between screen-film and full-field digital mammography. Cancer conspicuity was equal with both modalities. Full-field digital mammography with soft-copy reading is comparable to screen-film mammography in population-based screening.

Ten-core versus 16-core transrectal ultrasonography guided prostate biopsy for detection of prostatic carcinoma: a prospective comparative study in Indian population

PubMed Central

Prakash, V. Surya; Mohan, G. Chandra; Krishnaiah, S. Venkata; Vijaykumar, V.; Babu, G. Ramesh; Reddy, G. Vijaya Bhaskar; Mahaboob, V. S.

2013-01-01

Purpose: To compare the cancer detection rate in patients with raised serum prostate-specific antigen (PSA) or abnormal digital rectal examination (DRE) results between the 10-core and the 16-core biopsy techniques in an Indian population. Methods: Between November 2010 and November 2012, 95 men aged >50 years who presented to the Urology Department with lower urinary tract symptoms, elevated serum PSA, and/or abnormal DRE findings underwent transrectal ultrasonography (TRUS)-guided prostate biopsy. A total of 53 patients underwent 10-core biopsy and 42 patients underwent 16-core biopsy. Results: Of the 53 men in the 10-core group, 8 had cancer, whereas in the 16-core biopsy group, 23 of 42 men had cancer. Detection of prostate cancer was significantly higher in patients who underwent 16-core biopsy than in those who underwent 10-core biopsy (P<0.001). Among the 95 men, 44 men had abnormal DRE findings (46.3%), of whom 23 showed cancer (52.27%). Of 51 men with normal DRE findings and elevated PSA, 8 men had malignancy with a cancer detection rate of 15.68%. Among 20 men with PSA between 4.1 and 10 ng/mL, 2 (10%) had cancer. In 31 men with PSA between 10.1 and 20 ng/mL, 3 cancers (9.67%) were detected, and in 44 men with PSA >20 ng/mL, 26 cancers were detected (59.09%). Conclusions: The cancer detection rate with 16-core TRUS-guided biopsy is significantly higher than that with 10-core biopsy (54.76% vs. 15.09%, P<0.001). In patients with both normal and abnormal DRE findings, 16-core biopsy has a better detection rate than the 10-core biopsy protocol. With increasing PSA, there is a high rate of detection of prostate cancer in both 10-core and 16-core biopsy patients. PMID:24392441

Ten-core versus 16-core transrectal ultrasonography guided prostate biopsy for detection of prostatic carcinoma: a prospective comparative study in Indian population.

PubMed

Prakash, V Surya; Mohan, G Chandra; Krishnaiah, S Venkata; Vijaykumar, V; Babu, G Ramesh; Reddy, G Vijaya Bhaskar; Mahaboob, V S

2013-01-01

To compare the cancer detection rate in patients with raised serum prostate-specific antigen (PSA) or abnormal digital rectal examination (DRE) results between the 10-core and the 16-core biopsy techniques in an Indian population. Between November 2010 and November 2012, 95 men aged >50 years who presented to the Urology Department with lower urinary tract symptoms, elevated serum PSA, and/or abnormal DRE findings underwent transrectal ultrasonography (TRUS)-guided prostate biopsy. A total of 53 patients underwent 10-core biopsy and 42 patients underwent 16-core biopsy. Of the 53 men in the 10-core group, 8 had cancer, whereas in the 16-core biopsy group, 23 of 42 men had cancer. Detection of prostate cancer was significantly higher in patients who underwent 16-core biopsy than in those who underwent 10-core biopsy (P<0.001). Among the 95 men, 44 men had abnormal DRE findings (46.3%), of whom 23 showed cancer (52.27%). Of 51 men with normal DRE findings and elevated PSA, 8 men had malignancy with a cancer detection rate of 15.68%. Among 20 men with PSA between 4.1 and 10 ng/mL, 2 (10%) had cancer. In 31 men with PSA between 10.1 and 20 ng/mL, 3 cancers (9.67%) were detected, and in 44 men with PSA >20 ng/mL, 26 cancers were detected (59.09%). The cancer detection rate with 16-core TRUS-guided biopsy is significantly higher than that with 10-core biopsy (54.76% vs. 15.09%, P<0.001). In patients with both normal and abnormal DRE findings, 16-core biopsy has a better detection rate than the 10-core biopsy protocol. With increasing PSA, there is a high rate of detection of prostate cancer in both 10-core and 16-core biopsy patients.

Evaluation of Traditional and Contemporary Methods for Detecting Syphacia obvelata and Aspiculuris tetraptera in Laboratory Mice

PubMed Central

Gerwin, Philip M; Arbona, Rodolfo J Ricart; Riedel, Elyn R; Lepherd, Michelle L; Henderson, Ken S; Lipman, Neil S

2017-01-01

There is no consensus regarding the best practice for detecting murine pinworm infections. Initially, we evaluated 7 fecal concentration methods by using feces containing Aspiculuris tetraptera (AT) eggs (n = 20 samples per method). Sodium nitrate flotation, sodium nitrate centrifugation, Sheather sugar centrifugation, and zinc sulfate centrifugation detected eggs in 100% of samples; zinc sulfate flotation and water sedimentation detected eggs in 90%. All had better detection rates than Sheather sugar flotation (50%). To determine optimal detection methods, Swiss Webster mice were exposed to Syphacia obvelata (SO; n = 60) or AT (n = 60). We compared the following methods at days 0, 30, and 90, beginning 21 or 28 d after SO and AT exposure, respectively: fecal concentration (AT only), anal tape test (SO only), direct examination of intestinal contents (cecum and colon), Swiss roll histology (cecum and colon), and PCR analysis (pooled fur swab and feces). Detection rates for SO-exposed mice were: PCR analysis, 45%; Swiss roll histology, 30%; intestinal content exam, 27%; and tape test, 27%. The SO detection rate for PCR analysis was significantly greater than that for the tape test. Detection rates for AT-exposed mice were: intestinal content exam, 53%; PCR analysis, 33%; fecal flotation, 22%; and Swiss roll histology, 17%. The AT detection rate of PCR analysis combined with intestinal content examination was greater than for PCR analysis only and the AT detection rate of intestinal content examination was greater than for Swiss roll histology. Combining PCR analysis with intestinal content examination detected 100% of infected animals. No single test detected all positive animals. We recommend combining PCR analysis with intestinal content examination for optimal pinworm detection. PMID:28905712

Benefits of double reading of screening mammograms: retrospective study on a consecutive series.

PubMed

Caumo, F; Brunelli, S; Zorzi, M; Baglio, I; Ciatto, S; Montemezzi, S

2011-06-01

The purpose of this study was to assess the performance of delayed second reading of screening mammograms when added to real-time reading plus immediate assessment. The study setting was the mammography screening programme of an Italian Local Health Unit. Recall rate and cancer detection rate at first reading or informed second reading only were assessed in a cohort of 23,629 women aged 50-69 years screened during 2007-2008. Incremental recall rate, incremental cancer detection rate and incremental cost of second reading were determined. Recall rate was 13.0% at first and 2.7% at second reading (incremental recall rate +21.1%). Overall, recalls were more frequent in the younger decade and in the presence of denser breasts. Cancer detection rate was 7.06‰ (n=167) at first and 0.93‰ (n=22) at second reading (incremental cancer detection rate +13.1%). Compared with first reading, second reading detected more cancers depicted as isolated microcalcifications and distortions (40.9% vs. 16.2%, p=0.02) and at a lower stage (stage 0-I 81.8% vs. 69.5%, p=0.34). The cost of adding delayed second reading was + 3.65 per screened individual or 3,926.61 per incremental cancer detected. The study confirms the efficacy of second reading, even as an adjunct to real-time single reading plus immediate assessment. Incremental recall rate is acceptable in view of the incremental cancer detection rate, and both figures are within the range of literature reports on double-reading performance.

Comparative analysis of total body vs. dermatoscopic photographic monitoring of nevi in similar patient populations at risk for cutaneous melanoma

PubMed Central

Goodson, Agnessa Gadeliya; Florell, Scott R.; Hyde, Mark; Bowen, Glen M.; Grossman, Douglas

2011-01-01

Background Our previous experience monitoring nevi in high risk patients by serial digital epiluminescence microscopy (DELM) photography achieved low biopsy rates, but was limited by melanomas presenting as new lesions or arising from nevi that had not been photographed. Objective To determine whether biopsy rates, efficiency of melanoma detection, and melanoma origin (de novo vs. nevus-derived) differed in a similar patient population monitored by total body (TB) photography. Methods 1076 patients (including 187 from prior cohort) underwent TB photography and were monitored using photographs obtained at the initial visit. Risk factors and median monitoring periods for these patients were comparable to patients previously monitored by DELM photography. Results 275 biopsies were performed in 467 patients on follow-up visits. Of 12 melanomas detected on follow-up, five were invasive; five presented as changing lesions and two as new lesions; nine arose de novo and the remainder was nevus-derived. Conclusions In our experience with both approaches, monitoring patients at risk for melanoma by TB (compared to DELM) photography was associated with lower biopsy rates and lower nevus to melanoma ratios, and facilitated detection of both new and changing lesions. In both cohorts, the majority of melanomas detected on follow-up arose de novo. PMID:20653722

COMPARISON OF RETINAL PATHOLOGY VISUALIZATION IN MULTISPECTRAL SCANNING LASER IMAGING.

PubMed

Meshi, Amit; Lin, Tiezhu; Dans, Kunny; Chen, Kevin C; Amador, Manuel; Hasenstab, Kyle; Muftuoglu, Ilkay Kilic; Nudleman, Eric; Chao, Daniel; Bartsch, Dirk-Uwe; Freeman, William R

2018-03-16

To compare retinal pathology visualization in multispectral scanning laser ophthalmoscope imaging between the Spectralis and Optos devices. This retrospective cross-sectional study included 42 eyes from 30 patients with age-related macular degeneration (19 eyes), diabetic retinopathy (10 eyes), and epiretinal membrane (13 eyes). All patients underwent retinal imaging with a color fundus camera (broad-spectrum white light), the Spectralis HRA-2 system (3-color monochromatic lasers), and the Optos P200 system (2-color monochromatic lasers). The Optos image was cropped to a similar size as the Spectralis image. Seven masked graders marked retinal pathologies in each image within a 5 × 5 grid that included the macula. The average area with detected retinal pathology in all eyes was larger in the Spectralis images compared with Optos images (32.4% larger, P < 0.0001), mainly because of better visualization of epiretinal membrane and retinal hemorrhage. The average detection rate of age-related macular degeneration and diabetic retinopathy pathologies was similar across the three modalities, whereas epiretinal membrane detection rate was significantly higher in the Spectralis images. Spectralis tricolor multispectral scanning laser ophthalmoscope imaging had higher rate of pathology detection primarily because of better epiretinal membrane and retinal hemorrhage visualization compared with Optos bicolor multispectral scanning laser ophthalmoscope imaging.

Detection of Movement Related Cortical Potentials from EEG Using Constrained ICA for Brain-Computer Interface Applications.

PubMed

Karimi, Fatemeh; Kofman, Jonathan; Mrachacz-Kersting, Natalie; Farina, Dario; Jiang, Ning

2017-01-01

The movement related cortical potential (MRCP), a slow cortical potential from the scalp electroencephalogram (EEG), has been used in real-time brain-computer-interface (BCI) systems designed for neurorehabilitation. Detecting MPCPs in real time with high accuracy and low latency is essential in these applications. In this study, we propose a new MRCP detection method based on constrained independent component analysis (cICA). The method was tested for MRCP detection during executed and imagined ankle dorsiflexion of 24 healthy participants, and compared with four commonly used spatial filters for MRCP detection in an offline experiment. The effect of cICA and the compared spatial filters on the morphology of the extracted MRCP was evaluated by two indices quantifying the signal-to-noise ratio and variability of the extracted MRCP. The performance of the filters for detection was then directly compared for accuracy and latency. The latency obtained with cICA (-34 ± 29 ms motor execution (ME) and 28 ± 16 ms for motor imagery (MI) dataset) was significantly smaller than with all other spatial filters. Moreover, cICA resulted in greater true positive rates (87.11 ± 11.73 for ME and 86.66 ± 6.96 for MI dataset) and lower false positive rates (20.69 ± 13.68 for ME and 19.31 ± 12.60 for MI dataset) compared to the other methods. These results confirm the superiority of cICA in MRCP detection with respect to previously proposed EEG filtering approaches.

Left lobe of the prostate during clinical prostate cancer screening: the dark side of the gland for right-handed examiners.

PubMed

Ploussard, G; Nicolaiew, N; Mongiat-Artus, P; Terry, S; Allory, Y; Vacherot, F; Abbou, C-C; Desgrandchamps, F; Salomon, L; de la Taille, A

2014-06-01

The predictive value of the abnormality side during digital rectal examination (DRE) has never been studied, suggesting that physicians examined the left lobe of the gland as well as the right lobe. We aimed to assess the predictive value of the side of DRE abnormality for prostate cancer (PCa) detection and aggressiveness in right-handed urologists. An analysis of a prospective database was carried out that included all consecutive men undergoing prostate biopsies between 2001 and 2012. The main end point was the predictive value of the abnormality side during DRE for cancer detection in clinically suspicious unilateral T2 disease. The diagnostic performance of left- versus right-sided abnormality was also assessed in terms of sensitivity, specificity and negative/positive predictive values. Overall, 308 patients had a suspicious unilateral clinical disease (detection rate 57.5%). The cancer detection rate was significantly higher in case of left-sided compared with right-sided clinical T2 stage (odds ratio 2.1). In case of left-sided disease, the number of positive cores, the rate of perineural invasion, the rate of primary grade 4 pattern and the percentage of cancer involvement per core were significantly higher compared with those reported for right-sided disease. The predictive value of abnormality laterality for cancer detection and aggressiveness remained statistically independent in multivariate models. The positive predictive value for cancer detection was 64.6 in case of suspicious left-sided disease versus 46.9 in case of right-sided disease. The risks of detecting PCa and aggressive disease on biopsy are significantly higher when DRE reveals a suspicious left-sided clinical disease as compared with right-sided disease. Right-handed physicians should be aware of this variance in diagnostic performance and potential underdetection of left-sided clinical disease, and should improve their examination of the left lobe of the gland by conducting longer exams or changing the patient's position.

Diagnostic accuracy of non-contrast abdominal CT scans performed as follow-up for patients with an established cancer diagnosis: a retrospective study.

PubMed

Semaan, Hassan; Bazerbashi, Mohamad F; Siesel, Geoffrey; Aldinger, Paul; Obri, Tawfik

2018-03-01

To determine the accuracy and non-detection rate of cancer related findings (CRFs) on follow-up non-contrast-enhanced CT (NECT) versus contrast-enhanced CT (CECT) images of the abdomen in patients with a known cancer diagnosis. A retrospective review of 352 consecutive CTs of the abdomen performed with and without IV contrast between March 2010 and October 2014 for follow-up of cancer was included. Two radiologists independently assessed the NECT portions of the studies. The reader was provided the primary cancer diagnosis and access to the most recent prior NECT study. The accuracy and non-detection rates were determined by comparing our results to the archived reports as a gold standard. A total of 383 CRFs were found in the archived reports of the 352 abdominal CTs. The average non-detection rate for the NECTs compared to the CECTs was 3.0% (11.5/383) with an accuracy of 97.0% (371.5/383) in identifying CRFs. The most common findings missed were vascular thrombosis with a non-detection rate of 100%. The accuracy for non-vascular CRFs was 99.1%. Follow-up NECT abdomen studies are highly accurate in the detection of CRFs in patients with an established cancer diagnosis, except in cases where vascular involvement is suspected.

Comparison of Zika virus (ZIKV) RNA detection in plasma, whole blood and urine - Case series of travel-associated ZIKV infection imported to Italy, 2016.

PubMed

Rossini, Giada; Gaibani, Paolo; Vocale, Caterina; Cagarelli, Roberto; Landini, Maria Paola

2017-09-01

The capability to detect ZIKV RNA is of crucial importance for cases confirmation. However, due to the short-lived viremia, the detection of ZIKV RNA in plasma/serum is challenging for samples collected more than one week after onset of clinical illness. We compared the window time and detection rate of ZIKV RNA in different specimen types (plasma, whole blood and urine) collected simultaneously at several times post-symptom onset. We examined the presence of ZIKV RNA in matched specimens of whole blood, plasma and urine collected in the same date (3-28 days after symptom onset) from 10 ZIKV infected patients. ZIKV RNA was found in plasma as late as 10 days after symptoms onset and tested positive in all 5 (100%) and in 2 of 6 (33,3%) plasma samples collected 1-5 and 6-10 days after symptoms onset, respectively. ZIKV RNA was positive in urine through the 21st day after symptom onset; the detection rate of ZIKV RNA in urine samples was 100% (11/11) for samples collected 1-10 days from symptoms onset, decreasing at later times of sampling. The detection rate of ZIKV RNA in whole blood was comparable to that in urine samples but extended the window of detection of ZIKV RNA up to 26 days after symptom onset. Our results highlight the usefulness of simultaneously testing multiple specimen types in order to extend the rate and the time frame of ZIKV RNA detection, increasing the possibility of cases confirmation through direct diagnosis in convalescence-phase of infection, supplementing serological data which are often difficult to interpret. Copyright © 2017 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

Auditory sensitivity to spectral modulation phase reversal as a function of modulation depth

PubMed Central

Grose, John

2018-01-01

The present study evaluated auditory sensitivity to spectral modulation by determining the modulation depth required to detect modulation phase reversal. This approach may be preferable to spectral modulation detection with a spectrally flat standard, since listeners appear unable to perform the task based on the detection of temporal modulation. While phase reversal thresholds are often evaluated by holding modulation depth constant and adjusting modulation rate, holding rate constant and adjusting modulation depth supports rate-specific assessment of modulation processing. Stimuli were pink noise samples, filtered into seven octave-wide bands (0.125–8 kHz) and spectrally modulated in dB. Experiment 1 measured performance as a function of modulation depth to determine appropriate units for adaptive threshold estimation. Experiment 2 compared thresholds in dB for modulation detection with a flat standard and modulation phase reversal; results supported the idea that temporal cues were available at high rates for the former but not the latter. Experiment 3 evaluated spectral modulation phase reversal thresholds for modulation that was restricted to either one or two neighboring bands. Flanking bands of unmodulated noise had a larger detrimental effect on one-band than two-band targets. Thresholds for high-rate modulation improved with increasing carrier frequency up to 2 kHz, whereas low-rate modulation appeared more consistent across frequency, particularly in the two-band condition. Experiment 4 measured spectral weights for spectral modulation phase reversal detection and found higher weights for bands in the spectral center of the stimulus than for the lowest (0.125 kHz) or highest (8 kHz) band. Experiment 5 compared performance for highly practiced and relatively naïve listeners, and found weak evidence of a larger practice effect at high than low spectral modulation rates. These results provide preliminary data for a task that may provide a better estimate of sensitivity to spectral modulation than spectral modulation detection with a flat standard. PMID:29621338

A source-attractor approach to network detection of radiation sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wu, Qishi; Barry, M. L..; Grieme, M.

Radiation source detection using a network of detectors is an active field of research for homeland security and defense applications. We propose Source-attractor Radiation Detection (SRD) method to aggregate measurements from a network of detectors for radiation source detection. SRD method models a potential radiation source as a magnet -like attractor that pulls in pre-computed virtual points from the detector locations. A detection decision is made if a sufficient level of attraction, quantified by the increase in the clustering of the shifted virtual points, is observed. Compared with traditional methods, SRD has the following advantages: i) it does not requiremore » an accurate estimate of the source location from limited and noise-corrupted sensor readings, unlike the localizationbased methods, and ii) its virtual point shifting and clustering calculation involve simple arithmetic operations based on the number of detectors, avoiding the high computational complexity of grid-based likelihood estimation methods. We evaluate its detection performance using canonical datasets from Domestic Nuclear Detection Office s (DNDO) Intelligence Radiation Sensors Systems (IRSS) tests. SRD achieves both lower false alarm rate and false negative rate compared to three existing algorithms for network source detection.« less

Improved detection rate of cytogenetic abnormalities in chronic lymphocytic leukemia and other mature B-cell neoplasms with use of CpG-oligonucleotide DSP30 and interleukin 2 stimulation.

PubMed

Shi, Min; Cipollini, Matthew J; Crowley-Bish, Patricia A; Higgins, Anne W; Yu, Hongbo; Miron, Patricia M

2013-05-01

Detection of cytogenetic abnormalities requires successful culture of the clonal population to obtain metaphase chromosomes for study, and as such, has been hampered by low mitotic indices of mature B cells in culture. Our study presents data on the improved abnormality detection rate with the use of a CpG-oligonucleotide/interleukin 2 (OL/IL-2) culture protocol for mature B-cell neoplasms, including chronic lymphocytic leukemia (CLL) and non-CLL specimens. The increased detection rate of abnormalities, compared with unstimulated culture and traditional pokeweed mitogen culture, was statistically significant for both CLL and non-CLL neoplasms. For CLL specimens, our data also showed that for cytogenetically visible aberrations, OL/IL-2 was as, if not more, sensitive than detection with interphase fluorescence in situ hybridization (iFISH). Use of OL/IL-2 allowed a number of abnormalities to be detected, which were not covered by specific iFISH panels, especially balanced translocations. Therefore, OL/IL-2 stimulation improves diagnostic sensitivity and increases discovery rate of novel prognostic findings.

Scottish Bowel Screening Programme Colonoscopy Quality - scope for improvement?

PubMed

Quyn, A J; Fraser, C G; Stanners, G; Carey, F A; Rees, C J; Moores, B; Steele, R J

2018-06-04

The delivery of the Scottish Bowel Screening Programme (SBoSP) is rooted in the provision of a high quality, effective and participant-centred service. Safe and effective colonoscopy forms an integral part of the process. Additional accreditation as part of a multi-faceted programme for participating colonoscopists, as in England, does not exist in Scotland. This study aimed to describe the quality of colonoscopy in the SBoSP and compare this to the English national screening standards. Data were collected from the SBoSP between 2007 and 2014. End-points for analysis were caecal intubation, cancer, polyp and adenoma detection, and complications. Overall results were compared with 2012 published English national standards for screening and outcomes from 2006-2009. During the study period 53,332 participants attended for colonoscopy. Colonoscopy completion rate was 95.6% overall. The mean cancer detection rate (CDR) was 7.1%, the polyp detection rate (PDR) 45.7% and the adenoma detection rate (ADR) was 35.5%.The overall complication rate was 0.47%. Colonoscopy quality in the SBoSP has exceeded the standard set for screening colonoscopy in England, despite not adopting a multi-faceted programme for screening colonoscopy. However, the overall ADR in Scotland was 9.1% lower than that in England which has implications for colonoscopy quality and may have an impact on the cancer prevention rates, a key aim of the SBoSP. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Using occupancy modelling to compare environmental DNA to traditional field methods for regional-scale monitoring of an endangered aquatic species.

PubMed

Schmelzle, Molly C; Kinziger, Andrew P

2016-07-01

Environmental DNA (eDNA) monitoring approaches promise to greatly improve detection of rare, endangered and invasive species in comparison with traditional field approaches. Herein, eDNA approaches and traditional seining methods were applied at 29 research locations to compare method-specific estimates of detection and occupancy probabilities for endangered tidewater goby (Eucyclogobius newberryi). At each location, multiple paired seine hauls and water samples for eDNA analysis were taken, ranging from two to 23 samples per site, depending upon habitat size. Analysis using a multimethod occupancy modelling framework indicated that the probability of detection using eDNA was nearly double (0.74) the rate of detection for seining (0.39). The higher detection rates afforded by eDNA allowed determination of tidewater goby occupancy at two locations where they have not been previously detected and at one location considered to be locally extirpated. Additionally, eDNA concentration was positively related to tidewater goby catch per unit effort, suggesting eDNA could potentially be used as a proxy for local tidewater goby abundance. Compared to traditional field sampling, eDNA provided improved occupancy parameter estimates and can be applied to increase management efficiency across a broad spatial range and within a diversity of habitats. © 2015 John Wiley & Sons Ltd.

GPU based cloud system for high-performance arrhythmia detection with parallel k-NN algorithm.

PubMed

Tae Joon Jun; Hyun Ji Park; Hyuk Yoo; Young-Hak Kim; Daeyoung Kim

2016-08-01

In this paper, we propose an GPU based Cloud system for high-performance arrhythmia detection. Pan-Tompkins algorithm is used for QRS detection and we optimized beat classification algorithm with K-Nearest Neighbor (K-NN). To support high performance beat classification on the system, we parallelized beat classification algorithm with CUDA to execute the algorithm on virtualized GPU devices on the Cloud system. MIT-BIH Arrhythmia database is used for validation of the algorithm. The system achieved about 93.5% of detection rate which is comparable to previous researches while our algorithm shows 2.5 times faster execution time compared to CPU only detection algorithm.

Characteristics of right-sided colonic neoplasia and colonoscopy barriers limiting their early detection and prognosis: a review of the literature.

PubMed

Fischbach, Wolfgang; Elsome, Rory; Amlani, Bharat

2018-06-05

Colonoscopy provides less protection from colorectal cancer in the right colon than the left. Areas covered: This review examines patient outcomes and colonoscopy success rates to identify factors that limit the protective effect of colonoscopy in the right colon. The MEDLINE and Embase databases were searched for literature from 2000 onwards, on the long-term outcomes and differences in screening practice between the right and left colon. In total, 12 systematic reviews (including nine meta-analyses) and 44 primary data records were included. Differences in patient outcomes and colonoscopy practice were identified between the right and left colon, suggesting that several factors, many of which disproportionally affect the right colon, impact lesion detection rates. Shorter withdrawal times reduce detection rates, while longer times significantly increase detection; mostly of adenomas in the right colon. Colonoscope attachments often only show a significant improvement in detection rates in the right colon, suggesting detection is more challenging due to visibility of the right colonic mucosa. Higher bowel cleansing grades significantly improve detection rates in the right colon compared to the left. Expert commentary: These findings confirm the need for continued improvement of colonoscopy effectiveness, and obligatory quality assessment, overall and especially in the right colon.

Pulmonary nodule detection in oncological patients - Value of respiratory-triggered, periodically rotated overlapping parallel T2-weighted imaging evaluated with PET/CT-MR.

PubMed

de Galiza Barbosa, Felipe; Geismar, Jan Henning; Delso, Gaspar; Messerli, Michael; Huellner, Martin; Stolzmann, Paul; Veit-Haibach, Patrick

2018-01-01

To prospectively evaluate the detection and conspicuity of pulmonary nodules in an oncological population, using a tri-modality PET/CT-MR protocol including a respiration-gated T2-PROPELLER sequence for possible integration into a simultaneous PET/MR protocol. 149 patients referred for staging of malignancy were prospectively enrolled in this single-center study. Imaging was performed on a tri-modality PET/CT-MR setup and was comprised of PET/CT and 3T-MR imaging with 3D dual-echo GRE pulse sequence (Dixon) and an axial respiration-gated T2-weighted PROPELLER (T2-P) sequence. Images were assessed for presence, conspicuity, size and interpretation of the pulmonary parenchymal nodules. McNemar's test was used to evaluate paired differences in nodule detection rates between MR and CT from PET/CT. The correlation of pulmonary nodule size in CT and MR imaging was assessed using Pearson correlation coefficient. 299 pulmonary nodules were detected on PET/CT. The detectability was significantly higher on T2-P (60%, p<0.01) compared to T1-weighted Dixon-type sequences (16.1-37.8%). T2-P had a significantly higher detection rate among FDG-positive (92.4%) and among confirmed malignant nodules (75.9%) compared to T1-Dixon. Nodules <10mm were detected less often by MR sequences than by CT (p < 0.01). However, nodules >10mm were detected equally well with T2-P (92.2%) and CT (p >0.05). In a per-patient analysis, there was no significant change in the clinical interpretation of the nodules detected with T2-P and CT. Despite the overall lower detection rate compared with CT, the free-breathing respiratory gating T2-w sequence showed higher detectability in all evaluated categories compared to breath-hold T1-weighted MR sequences. Specifically, the T2-P was found to be not statistically different from CT in FDG-positive nodules, in detection of nodules >10mm and concerning conspicuity of pulmonary nodules. Overall, the additional time investment into T2-P seems to be justified since clinical relevant assessment of pulmonary lung nodules can mostly be done by T2-P in a whole body PET/MR staging of oncologic patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Reformatted images improve the detection rate of acute traumatic subdural hematomas on brain CT compared with axial images alone.

PubMed

Amrhein, Timothy J; Mostertz, William; Matheus, Maria Gisele; Maass-Bolles, Genevieve; Sharma, Komal; Collins, Heather R; Kranz, Peter G

2017-02-01

Subdural hematomas (SDHs) comprise a significant percentage of missed intracranial hemorrhage on axial brain CT. SDH detection rates could be improved with the addition of reformatted images. Though performed at some centers, the potential additional diagnostic sensitivity of reformatted images has not yet been investigated. The purpose of our study is to determine if the addition of coronal and sagittal reformatted images to an axial brain CT increases the sensitivity and specificity for detection of acute traumatic SDH. We retrospectively reviewed consecutive brain CTs acquired for acute trauma that contained new SDHs. An equivalent number of normal brain CTs served as control. Paired sets of images were created for each case: (1) axial images only ("axial only") and (2) axial, coronal, sagittal images ("reformat added"). Three readers interpreted both the axial only and companion reformat added for each case, separated by 1 month. Reading times and SDH detection rates were compared. One hundred SDH and 100 negative examinations were collected. Sensitivity and specificity for the axial-only scans were 75.7 and 94.3 %, respectively, compared with 88.3 and 98.3 % for reformat added. There was a 24.3 % false negative (missed SDH) rate with axial-only scans versus 11.7 % with reformat added (p = <0.001). Median reader interpretation times were longer with the addition of reformatted images (125 versus 89 s), but this difference was not significant (p = 0.23). The addition of coronal and sagittal images in trauma brain CT resulted in improved sensitivity and specificity as well as a reduction in SDH false negatives by greater than 50 %. Reformatted images substantially reduce the number of missed SDHs compared with axial images alone.

Implementation of Synthesized Two-dimensional Mammography in a Population-based Digital Breast Tomosynthesis Screening Program

PubMed Central

Zuckerman, Samantha P.; Keller, Brad M.; Maidment, Andrew D. A.; Barufaldi, Bruno; Weinstein, Susan P.; Synnestvedt, Marie; McDonald, Elizabeth S.

2016-01-01

Purpose To evaluate the early implementation of synthesized two-dimensional (s2D) mammography in a population screened entirely with s2D and digital breast tomosynthesis (DBT) (referred to as s2D/DBT) and compare recall rates and cancer detection rates to historic outcomes of digital mammography combined with DBT (referred to as digital mammography/DBT) screening. Materials and Methods This was an institutional review board–approved and HIPAA-compliant retrospective interpretation of prospectively acquired data with waiver of informed consent. Compared were recall rates, biopsy rates, cancer detection rates, and radiation dose for 15 571 women screened with digital mammography/DBT from October 1, 2011, to February 28, 2013, and 5366 women screened with s2D/DBT from January 7, 2015, to June 30, 2015. Two-sample z tests of equal proportions were used to determine statistical significance. Results Recall rate for s2D/DBT versus digital mammography/DBT was 7.1% versus 8.8%, respectively (P < .001). Biopsy rate for s2D/DBT versus digital mammography/DBT decreased (1.3% vs 2.0%, respectively; P = .001). There was no significant difference in cancer detection rate for s2D/DBT versus digital mammography/DBT (5.03 of 1000 vs 5.45 of 1000, respectively; P = .72). The average glandular dose was 39% lower in s2D/DBT versus digital mammography/DBT (4.88 mGy vs 7.97 mGy, respectively; P < .001). Conclusion Screening with s2D/DBT in a large urban practice resulted in similar outcomes compared with digital mammography/DBT imaging. Screening with s2D/DBT allowed for the benefits of DBT with a decrease in radiation dose compared with digital mammography/DBT. © RSNA, 2016 An earlier incorrect version of this article appeared online. This article was corrected on August 11, 2016. PMID:27467468

Back-to-back colon capsule endoscopy and optical colonoscopy in colorectal cancer screening individuals.

PubMed

Kobaek-Larsen, M; Kroijer, R; Dyrvig, A-K; Buijs, M M; Steele, R J C; Qvist, N; Baatrup, G

2018-06-01

The aim was to determine the polyp detection rate and per-patient sensitivity for polyps > 9 mm of colon capsule endoscopy (CCE) compared with colonoscopy as well as the diagnostic accuracy of CCE. Individuals who had a positive immunochemical faecal occult blood test during screening had investigator blinded CCE and colonoscopy. Participants underwent repeat endoscopy if significant lesions detected by CCE were considered to have been missed by colonoscopy. There were 253 participants. The polyp detection rate was significantly higher in CCE compared with colonoscopy (P = 0.02). The per-patient sensitivity for > 9 mm polyps for CCE and colonoscopy was 87% (95% CI: 83-91%) and 88% (95% CI: 84-92%) respectively. In participants with complete CCE and colonoscopy examinations (N = 126), per-patient sensitivity of > 9 mm polyps in CCE (97%; 95% CI: 94-100%) was superior to colonoscopy (89%; 95% CI: 84-94%). A complete capsule endoscopy examination (N = 134) could detect patients with intermediate or greater risk (according to the European guidelines) with an accuracy, sensitivity, specificity and positivity rate of 79%, 93%, 69% and 58% respectively, using a cut-off of at least one polyp > 10 mm or more than two polyps. CCE is superior to colonoscopy in polyp detection rate and per-patient sensitivity to > 9 mm polyps, but only in complete CCE examinations. The rate of incomplete CCE examinations must be improved. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

[Does intraoperative nerve monitoring reduce the rate of recurrent nerve palsies during thyroid surgery?].

PubMed

Timmermann, W; Dralle, H; Hamelmann, W; Thomusch, O; Sekulla, C; Meyer, Th; Timm, S; Thiede, A

2002-05-01

Two different aspects of the influence of neuromonitoring on the possible reduction of post-operative recurrent laryngeal nerve palsies require critical examination: the nerve identification and the monitoring of it's functions. Due to the additional information from the EMG signals, neuromonitoring is the best method for identifying the nerves as compared to visual identification alone. There are still no randomized studies available that compare the visual and electrophysiological recurrent laryngeal nerve detection in thyroid operations with respect to the postoperative nerve palsies. Nevertheless, comparisons with historical collectives show that a constant low nerve-palsy-rate was achieved with electrophysiological detection in comparison to visual detection. The rate of nerve identification is normally very high and amounts to 99 % in our own patients. The data obtained during the "Quality assurance of benign and malignant Goiter" study show that in hemithyreoidectomy and subtotal resection, lower nerve-palsy-rates are achieved with neuromonitoring as compared to solely visual detection. Following subtotal resection, this discrepancy becomes even statistically significant. While monitoring the nerve functions with the presently used neuromonitoring technique, it is possible to observe the EMG-signal remaining constant or decreasing in volume. Assuming that a constant neuromonitoring signal represents a normal vocal cord, our evaluation shows that there is a small percentage of false negative and positive results. Looking at the permanent recurrent nerve palsy rates, this method has a specificity of 98 %, a sensitivity of 100 %, a positive prognostic value of 10 %, and a negative prognostic value of 100 %. Although an altered neuromonitoring signal can be taken as a clear indication of eventual nerve damage, an absolutely reliable statement about the postoperative vocal cord function is presently not possible with intraoperative neuromonitoring.

Effect of hunter selectivity on harvest rates of radio-collared white-tailed deer in Pennsylvania

USGS Publications Warehouse

Buderman, Frances E.; Diefenbach, Duane R.; Rosenberry, C.S.; Wallingford, Bret D.; Long, Eric S.

2014-01-01

Radio transmitters are a commonly used tool for monitoring the fates of harvested species, although little research has been devoted to whether a visible radio transmitter changes a hunters' willingness to harvest that animal. We initially surveyed deer hunters to assess their willingness to harvest radio-collared deer and predicted radio collars were unlikely to affect the harvest of antlerless deer, but hunters may be less willing to harvest small-antlered males with radio collars compared to large-antlered males. We fitted white-tailed deer (Odocoileus virginianus) with radio collars that were visible to hunters or with ear-tag transmitters or ear-tags that were difficult to detect visually and estimated if harvest rates differed among marking methods. For females, the best model failed to detect an effect of radio collars on harvest rates. Also, we failed to detect a difference between male deer fitted with radio collars and ear-tag transmitters. When we compared males fitted with radio collars versus ear tags, we found harvest rate patterns were opposite to our predictions, with lower harvest rates for adult males fitted with radio collars and higher harvest rates for yearling males fitted with radio collars. Our study suggests that harvest rate estimates generated from a sample of deer fitted with visible radio collars can be representative of the population of inference. 

Immunohistochemistry and Polymerase Chain Reaction for Detection Human Papilloma Virus in Warts: A Comparative Study

PubMed Central

Lee, Hong Sun; Lee, Ji Hyun; Choo, Ji Yoon; Byun, Hee Jin; Jun, Jin Hyun

2016-01-01

Background Immunohistochemistry and polymerase chain reaction (PCR) are the most widely used methods for the detection of viruses. PCR is known to be a more sensitive and specific method than the immunohistochemical method at this time, but PCR has the disadvantages of high cost and skilled work to use widely. With the progress of technology, the immunohistochemical methods used in these days has come to be highly sensitive and actively used in the diagnostic fields. Objective To evaluate and compare the usefulness of immunohistochemistry and PCR for detection human papilloma virus (HPV) in wart lesions. Methods Nine biopsy samples of verruca vulgaris and 10 of condyloma accuminatum were examined. Immunohistochemical staining using monoclonal antibody to HPV L1 capsid protein and PCR were done for the samples. DNA sequencing of the PCR products and HPV genotyping were also done. Results HPV detection rate was 78.9% (88.9% in verruca vulgaris, 70.0% in condyloma accuminatum) on immunohistochemistry and 100.0% for PCR. HPV-6 genotype showed a lower positivity rate on immunohistochemistry (50.0%) as compared to that of the other HPV genotypes. Conclusion Immunohistochemistry for HPV L1 capsid protein showed comparable sensitivity for detection HPV. Considering the high cost and great effort needed for the PCR methods, we can use immunohistochemistry for HPV L1 capsid protein with the advantage of lower cost and simple methods for HPV detection. PMID:27489431

Comparison of four different methods for detection of biofilm formation by uropathogens.

PubMed

Panda, Pragyan Swagatika; Chaudhary, Uma; Dube, Surya K

2016-01-01

Urinary tract infection (UTI) is one of the most common infectious diseases encountered in clinical practice. Emerging resistance of the uropathogens to the antimicrobial agents due to biofilm formation is a matter of concern while treating symptomatic UTI. However, studies comparing different methods for detection of biofilm by uropathogens are scarce. To compare four different methods for detection of biofilm formation by uropathogens. Prospective observational study conducted in a tertiary care hospital. Totally 300 isolates from urinary samples were analyzed for biofilm formation by four methods, that is, tissue culture plate (TCP) method, tube method (TM), Congo Red Agar (CRA) method and modified CRA (MCRA) method. Chi-square test was applied when two or more set of variables were compared. P < 0.05 considered as statistically significant. Considering TCP to be a gold standard method for our study we calculated other statistical parameters. The rate of biofilm detection was 45.6%, 39.3% and 11% each by TCP, TM, CRA and MCRA methods, respectively. The difference between TCP and only CRA/MCRA was significant, but not that between TCP and TM. There was no difference in the rate of biofilm detection between CRA and MCRA in other isolates, but MCRA is superior to CRA for detection of the staphylococcal biofilm formation. TCP method is the ideal method for detection of bacterial biofilm formation by uropathogens. MCRA method is superior only to CRA for detection of staphylococcal biofilm formation.

Use of Selective Fungal Culture Media Increases Rates of Detection of Fungi in the Respiratory Tract of Cystic Fibrosis Patients.

PubMed

Hong, Gina; Miller, Heather B; Allgood, Sarah; Lee, Richard; Lechtzin, Noah; Zhang, Sean X

2017-04-01

The prevalence of fungi in the respiratory tracts of cystic fibrosis (CF) patients has risen. However, fungal surveillance is not routinely performed in most clinical centers in the United States, which may lead to an underestimation of the true prevalence of the problem. We conducted a prospective study comparing the rates of detection for clinically important fungi (CIF), defined as Aspergillus , Scedosporium , and Trichosporon species and Exophiala dermatitidis , in CF sputa using standard bacterial and selective fungal culture media, including Sabouraud dextrose agar with gentamicin (SDA), inhibitory mold agar (IMA), and brain heart infusion (BHI) agar with chloramphenicol and gentamicin. We described the prevalence of these fungi in an adult CF population. A total of 487 CF respiratory samples were collected from 211 unique participants. CIF were detected in 184 (37.8%) samples. Only 26.1% of CIF-positive samples were detected in bacterial culture medium, whereas greater rates of detection for fungi were found in IMA (65.8%; P < 0.001), in SDA (at 30°C, 64.7%; P = 0.005), and in BHI agar (63.0%; P = 0.001). The prevalences of Aspergillus and Scedosporium species were 40.8% and 5.2%, respectively, which are greater than the nationally reported prevalence numbers of 20.4% and 1.9%. Selective fungal culture media and longer incubation periods yielded higher rates of detection for CIF in CF sputum samples compared with that detected in bacterial culture medium, resulting in an underdetection of fungi by bacterial culture alone. The prevalence of fungi in CF may be better estimated by using selective fungal culture media, and this may translate to important clinical decisions. Copyright © 2017 American Society for Microbiology.

Use of Selective Fungal Culture Media Increases Rates of Detection of Fungi in the Respiratory Tract of Cystic Fibrosis Patients

PubMed Central

Hong, Gina; Miller, Heather B.; Allgood, Sarah; Lee, Richard; Lechtzin, Noah

2017-01-01

ABSTRACT The prevalence of fungi in the respiratory tracts of cystic fibrosis (CF) patients has risen. However, fungal surveillance is not routinely performed in most clinical centers in the United States, which may lead to an underestimation of the true prevalence of the problem. We conducted a prospective study comparing the rates of detection for clinically important fungi (CIF), defined as Aspergillus, Scedosporium, and Trichosporon species and Exophiala dermatitidis, in CF sputa using standard bacterial and selective fungal culture media, including Sabouraud dextrose agar with gentamicin (SDA), inhibitory mold agar (IMA), and brain heart infusion (BHI) agar with chloramphenicol and gentamicin. We described the prevalence of these fungi in an adult CF population. A total of 487 CF respiratory samples were collected from 211 unique participants. CIF were detected in 184 (37.8%) samples. Only 26.1% of CIF-positive samples were detected in bacterial culture medium, whereas greater rates of detection for fungi were found in IMA (65.8%; P < 0.001), in SDA (at 30°C, 64.7%; P = 0.005), and in BHI agar (63.0%; P = 0.001). The prevalences of Aspergillus and Scedosporium species were 40.8% and 5.2%, respectively, which are greater than the nationally reported prevalence numbers of 20.4% and 1.9%. Selective fungal culture media and longer incubation periods yielded higher rates of detection for CIF in CF sputum samples compared with that detected in bacterial culture medium, resulting in an underdetection of fungi by bacterial culture alone. The prevalence of fungi in CF may be better estimated by using selective fungal culture media, and this may translate to important clinical decisions. PMID:28100601

T wave alternans during exercise and atrial pacing in humans

NASA Technical Reports Server (NTRS)

Hohnloser, S. H.; Klingenheben, T.; Zabel, M.; Li, Y. G.; Albrecht, P.; Cohen, R. J.

1997-01-01

INTRODUCTION: Evidence is accumulating that microvolt T wave alternans (TWA) is a marker of increased risk for ventricular tachyarrhythmias. Initially, atrial pacing was used to elevate heart rate and elicit TWA. More recently, a noninvasive approach has been developed that elevates heart rate using exercise. METHODS AND RESULTS: In 30 consecutive patients with a history of ventricular tachyarrhythmias, the spectral method was used to detect TWA during both atrial pacing and submaximal exercise testing. The concordance rate for the presence or absence of TWA using the two measurement methods was 84%. There was a patient-specific heart rate threshold for the detection of TWA that averaged 100 +/- 14 beats/min during exercise compared with 97 +/- 9 beats/min during right atrial pacing (P = NS). Beyond this threshold, there was a significant and comparable increase in level of TWA with decreasing pacing cycle length and increasing exercise heart rates. CONCLUSIONS: The present study is the first to demonstrate that microvolt TWA can be assessed reliably and noninvasively during exercise stress. There is a patient-specific heart rate threshold beyond which TWA continues to increase with increasing heart rates. Heart rate thresholds for the onset of TWA measured during atrial pacing and exercise stress were comparable, indicating that heart rate alone appears to be the main factor of determining the onset of TWA during submaximal exercise stress.

Interpreting the gamma statistic in phylogenetic diversification rate studies: a rate decrease does not necessarily indicate an early burst.

PubMed

Fordyce, James A

2010-07-23

Phylogenetic hypotheses are increasingly being used to elucidate historical patterns of diversification rate-variation. Hypothesis testing is often conducted by comparing the observed vector of branching times to a null, pure-birth expectation. A popular method for inferring a decrease in speciation rate, which might suggest an early burst of diversification followed by a decrease in diversification rate is the gamma statistic. Using simulations under varying conditions, I examine the sensitivity of gamma to the distribution of the most recent branching times. Using an exploratory data analysis tool for lineages through time plots, tree deviation, I identified trees with a significant gamma statistic that do not appear to have the characteristic early accumulation of lineages consistent with an early, rapid rate of cladogenesis. I further investigated the sensitivity of the gamma statistic to recent diversification by examining the consequences of failing to simulate the full time interval following the most recent cladogenic event. The power of gamma to detect rate decrease at varying times was assessed for simulated trees with an initial high rate of diversification followed by a relatively low rate. The gamma statistic is extraordinarily sensitive to recent diversification rates, and does not necessarily detect early bursts of diversification. This was true for trees of various sizes and completeness of taxon sampling. The gamma statistic had greater power to detect recent diversification rate decreases compared to early bursts of diversification. Caution should be exercised when interpreting the gamma statistic as an indication of early, rapid diversification.

Refinement of detecting atrial fibrillation in stroke patients: results from the TRACK-AF Study.

PubMed

Reinke, F; Bettin, M; Ross, L S; Kochhäuser, S; Kleffner, I; Ritter, M; Minnerup, J; Dechering, D; Eckardt, L; Dittrich, R

2018-04-01

Detection of occult atrial fibrillation (AF) is crucial for optimal secondary prevention in stroke patients. The AF detection rate was determined by implantable cardiac monitor (ICM) and compared to the prediction rate of the probability of incident AF by software based analysis of a continuously monitored electrocardiogram at follow-up (stroke risk analysis, SRA); an optimized AF detection algorithm is proposed by combining both tools. In a monocentric prospective study 105 out of 389 patients with cryptogenic stroke despite extensive diagnostic workup were investigated with two additional cardiac monitoring tools: (a) 20 months' monitoring by ICM and (b) SRA during hospitalization at the stroke unit. The detection rate of occult AF was 18% by ICM (n = 19) (range 6-575 days) and 62% (n = 65) had an increased risk for AF predicted by SRA. When comparing the predictive accuracy of SRA to ICM, the sensitivity was 95%, specificity 35%, positive predictive value 27% and negative predictive value 96%. In 18 patients with AF detected by ICM, SRA also showed a medium risk for AF. Only one patient with a very low risk predicted by SRA developed AF revealed by ICM after 417 days. A combination of SRA and ICM is a promising strategy to detect occult AF. SRA is reliable in predicting incident AF with a high negative predictive value. Thus, SRA may serve as a cost-effective pre-selection tool identifying patients at risk for AF who may benefit from further cardiac monitoring by ICM. © 2017 EAN.

Automatic QRS complex detection using two-level convolutional neural network.

PubMed

Xiang, Yande; Lin, Zhitao; Meng, Jianyi

2018-01-29

The QRS complex is the most noticeable feature in the electrocardiogram (ECG) signal, therefore, its detection is critical for ECG signal analysis. The existing detection methods largely depend on hand-crafted manual features and parameters, which may introduce significant computational complexity, especially in the transform domains. In addition, fixed features and parameters are not suitable for detecting various kinds of QRS complexes under different circumstances. In this study, based on 1-D convolutional neural network (CNN), an accurate method for QRS complex detection is proposed. The CNN consists of object-level and part-level CNNs for extracting different grained ECG morphological features automatically. All the extracted morphological features are used by multi-layer perceptron (MLP) for QRS complex detection. Additionally, a simple ECG signal preprocessing technique which only contains difference operation in temporal domain is adopted. Based on the MIT-BIH arrhythmia (MIT-BIH-AR) database, the proposed detection method achieves overall sensitivity Sen = 99.77%, positive predictivity rate PPR = 99.91%, and detection error rate DER = 0.32%. In addition, the performance variation is performed according to different signal-to-noise ratio (SNR) values. An automatic QRS detection method using two-level 1-D CNN and simple signal preprocessing technique is proposed for QRS complex detection. Compared with the state-of-the-art QRS complex detection approaches, experimental results show that the proposed method acquires comparable accuracy.

Comparing the effects of age on amplitude modulation and frequency modulation detection.

PubMed

Wallaert, Nicolas; Moore, Brian C J; Lorenzi, Christian

2016-06-01

Frequency modulation (FM) and amplitude modulation (AM) detection thresholds were measured at 40 dB sensation level for young (22-28 yrs) and older (44-66 yrs) listeners with normal audiograms for a carrier frequency of 500 Hz and modulation rates of 2 and 20 Hz. The number of modulation cycles, N, varied between 2 and 9. For FM detection, uninformative AM at the same rate as the FM was superimposed to disrupt excitation-pattern cues. For both groups, AM and FM detection thresholds were lower for the 2-Hz than for the 20-Hz rate, and AM and FM detection thresholds decreased with increasing N. Thresholds were higher for older than for younger listeners, especially for FM detection at 2 Hz, possibly reflecting the effect of age on the use of temporal-fine-structure cues for 2-Hz FM detection. The effect of increasing N was similar across groups for both AM and FM. However, at 20 Hz, older listeners showed a greater effect of increasing N than younger listeners for both AM and FM. The results suggest that ageing reduces sensitivity to both excitation-pattern and temporal-fine-structure cues for modulation detection, but more so for the latter, while sparing temporal integration of these cues at low modulation rates.

Analysis of Infrared Signature Variation and Robust Filter-Based Supersonic Target Detection

PubMed Central

Sun, Sun-Gu; Kim, Kyung-Tae

2014-01-01

The difficulty of small infrared target detection originates from the variations of infrared signatures. This paper presents the fundamental physics of infrared target variations and reports the results of variation analysis of infrared images acquired using a long wave infrared camera over a 24-hour period for different types of backgrounds. The detection parameters, such as signal-to-clutter ratio were compared according to the recording time, temperature and humidity. Through variation analysis, robust target detection methodologies are derived by controlling thresholds and designing a temporal contrast filter to achieve high detection rate and low false alarm rate. Experimental results validate the robustness of the proposed scheme by applying it to the synthetic and real infrared sequences. PMID:24672290

Detection of K-ras gene mutations in feces by magnetic nanoprobe in patients with pancreatic cancer: A preliminary study.

PubMed

Wang, Xiaoguang; Wang, Jingshuai; Chen, Fei; Zhong, Zhengxiang; Qi, Lifeng

2018-01-01

The present study aimed to investigate the feasibility and effectiveness of detecting K-ras mutation by using magnetic nanoparticles in fecal samples of patients with pancreatic cancer at different stages. The novel methodology of K-ras mutation detection was compared to the existing methodology of cancer antigen (CA)19-9 examination. Patients with pancreatic cancer (n=88), pancreatic benign diseases who displayed chronic pancreatitis (n=35), pancreatic mucinous cyst neoplasms (n=10) and pancreatic serous cyst (n=9) admitted to the Department of Surgery, Jiaxing Second Hospital were enrolled in the present study. Fecal samples were collected from all patients, DNA was extracted and magnetic nanoprobe was then used to detect K-ras mutation. The results obtained using the novel magnetic nanoprobe detection technique showed a K-ras mutation rate of 81.8% (72/88) in the patients with pancreatic cancer and 18.5% (10/54) in patients with pancreatic benign diseases. In patients with pancreatic cancer, the K-ras mutation rate was comparable in stages I + IIA and IIB + III + IV (78.9 vs. 84.0%; P>0.05). The sensitivity and specificity of K-ras mutation for detection of pancreatic cancer was 81.8 and 81.5%, respectively. Sixty-eight pancreatic cancer patients had >37 U/ml CA99 with a sensitivity and specificity for pancreatic cancer detection of 77.3 and 77.8%, which was not significantly lower than detection by the fecal K-ras mutations (P>0.05). Combinational detection of fecal K-ras mutations and serum CA19-9 significantly increased the sensitivity regarding pancreatic cancer detection to 97.7% (P<0.05), while the specificity was not enhanced (80.9%; P>0.05) compared with fecal K-ras mutations or CA19-9 alone. The findings showed that the magnetic nanoprobe is able to detect fecal K-ras mutations in different stages of pancreatic cancer, with comparable sensitivity and specificity to CA19-9 examination for differentiating pancreatic cancer. Furthermore, combined detection of CA19-9 and K-ras mutations has enhanced sensitivity compared with CA19-9 alone.

Mammographic screening in Sami speaking municipalities and a control group. Are early outcome measures influenced by ethnicity?

PubMed

Norum, Jan; Hofvind, Solveig; Nieder, Carsten; Schnell, Edrun Andrea; Broderstad, Ann Ragnhild

2012-04-16

Female citizens of Sami (the indigenous people of Norway) municipalities in northern Norway have a low risk of breast cancer. The objective of this study was to describe the attendance rate and outcome of the Norwegian Breast Cancer Screening Program (NBCSP) in the Sami-speaking municipalities and a control group. A retrospective registry-based study. The 8 municipalities included in the administration area of the Sami language law (Sami) were matched with a control group of 11 municipalities (non-Sami). Population data were accessed from Statistics Norway. Data regarding invitations and outcome in the NBCSP during the period 2001-2010 was derived from the Cancer Registry of Norway (CRN). The NBCSP targets women aged 50-69 years. Rates and percentages were compared using chi-square test with a p-value<0.05 as statistical significant. The attendance rate in the NBCSP was 78% in the Sami and 75% in the non-Sami population (p< 0.01). The recall rates were 2.4 and 3.3% in the Sami and non-Sami population, respectively (p<0.01). The rate of invasive screen detected cancer was not significantly lower in the Sami group (p=0.14). The percentage of all breast cancers detected in the NBCSP among the Sami (67%) was lower compared with the non-Sami population (86%, p=0.06). Despite a lower risk of breast cancer, the Sami attended the NBCSP more frequently than the control group. The recall and cancer detection rate was lower among the Sami compared with the non-Sami group.

High-Frame-Rate Doppler Ultrasound Using a Repeated Transmit Sequence

PubMed Central

Podkowa, Anthony S.; Oelze, Michael L.; Ketterling, Jeffrey A.

2018-01-01

The maximum detectable velocity of high-frame-rate color flow Doppler ultrasound is limited by the imaging frame rate when using coherent compounding techniques. Traditionally, high quality ultrasonic images are produced at a high frame rate via coherent compounding of steered plane wave reconstructions. However, this compounding operation results in an effective downsampling of the slow-time signal, thereby artificially reducing the frame rate. To alleviate this effect, a new transmit sequence is introduced where each transmit angle is repeated in succession. This transmit sequence allows for direct comparison between low resolution, pre-compounded frames at a short time interval in ways that are resistent to sidelobe motion. Use of this transmit sequence increases the maximum detectable velocity by a scale factor of the transmit sequence length. The performance of this new transmit sequence was evaluated using a rotating cylindrical phantom and compared with traditional methods using a 15-MHz linear array transducer. Axial velocity estimates were recorded for a range of ±300 mm/s and compared to the known ground truth. Using these new techniques, the root mean square error was reduced from over 400 mm/s to below 50 mm/s in the high-velocity regime compared to traditional techniques. The standard deviation of the velocity estimate in the same velocity range was reduced from 250 mm/s to 30 mm/s. This result demonstrates the viability of the repeated transmit sequence methods in detecting and quantifying high-velocity flow. PMID:29910966

Adaboost multi-view face detection based on YCgCr skin color model

NASA Astrophysics Data System (ADS)

Lan, Qi; Xu, Zhiyong

2016-09-01

Traditional Adaboost face detection algorithm uses Haar-like features training face classifiers, whose detection error rate is low in the face region. While under the complex background, the classifiers will make wrong detection easily to the background regions with the similar faces gray level distribution, which leads to the error detection rate of traditional Adaboost algorithm is high. As one of the most important features of a face, skin in YCgCr color space has good clustering. We can fast exclude the non-face areas through the skin color model. Therefore, combining with the advantages of the Adaboost algorithm and skin color detection algorithm, this paper proposes Adaboost face detection algorithm method that bases on YCgCr skin color model. Experiments show that, compared with traditional algorithm, the method we proposed has improved significantly in the detection accuracy and errors.

Detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia.

PubMed

Miyashita, Naoyuki; Kawai, Yasuhiro; Tanaka, Takaaki; Akaike, Hiroto; Teranishi, Hideto; Wakabayashi, Tokio; Nakano, Takashi; Ouchi, Kazunobu; Okimoto, Niro

2015-07-01

To clarify the detection failure rate of chest radiography for the identification of nursing and healthcare-associated pneumonia (NHCAP), we compared high-resolution computed tomography (HRCT) with chest radiography simultaneously for patients with clinical symptoms and signs leading to a suspicion of NHCAP. We analyzed 208 NHCAP cases and compared them based on four groups defined using NHCAP criteria, patients who were: Group A) resident in an extended care facility or nursing home; Group B) discharged from a hospital within the preceding 90 days; Group C) receiving nursing care and had poor performance status; and Group D) receiving regular endovascular treatment. Chest radiography was inferior to HRCT for the identification of pneumonia (149 vs 208 cases, p < 0.0001). Among the designated NHCAP criteria, chest radiography identified pneumonia cases at a significantly lower frequency than HRCT in Group A (70 vs 97 cases, p = 0.0190) and Group C (86 vs 136 cases, p < 0.0001). The detection failure rate of chest radiography differed among NHCAP criteria; 27.8% in Group A, 26.5% in Group B, 36.7% in Group C and 5.8% in Group D. Cerebrovascular disease and poor functional status were significantly more frequent in patients in Groups A and C compared with those in Groups B and D. Physicians may underestimate pneumonia shadow in chest radiographs in patients with NHCAP, and the detection failure rate of chest radiography differed among NHCAP criteria. Poor functional status may correlate with the low accuracy of chest radiography in diagnosing pneumonia. Copyright © 2015. Published by Elsevier Ltd.

Evaluation of nutrient agar for the culture of Mycobacterium tuberculosis using the microcolony detection method.

PubMed

Satti, L; Abbasi, S; Faiz, U

2012-07-01

We evaluated nutrient agar using the microcolony detection method for the recovery of Mycobacterium tuberculosis on 37 acid-fast bacilli (AFB) positive sputum specimens, and compared it with conventional Löwenstein-Jensen (LJ) medium. Nutrient agar detected 35 isolates compared to 34 on LJ medium. The mean time to detection of mycobacteria on nutrient agar and LJ medium was respectively 9.6 and 21.4 days. The contamination rate on nutrient agar and LJ medium was respectively 5.4% and 2.7%. Nutrient agar detects M. tuberculosis more rapidly than LJ medium, and could be an economical, rapid culture method in resource-poor settings, provided our findings are confirmed by further studies.

Comparison of the functional rating index and the 18-item Roland-Morris Disability Questionnaire: responsiveness and reliability.

PubMed

Chansirinukor, Wunpen; Maher, Christopher G; Latimer, Jane; Hush, Julia

2005-01-01

Retrospective design. To compare the responsiveness and test-retest reliability of the Functional Rating Index and the 18-item version of the Roland-Morris Disability Questionnaire in detecting change in disability in patients with work-related low back pain. Many low back pain-specific disability questionnaires are available, including the Functional Rating Index and the 18-item version of the Roland-Morris Disability Questionnaire. No previous study has compared the responsiveness and reliability of these questionnaires. Files of patients who had been treated for work-related low back pain at a physical therapy clinic were reviewed, and those containing initial and follow-up Functional Rating Index and 18-item Roland-Morris Disability Questionnaires were selected. The responsiveness of both questionnaires was compared using two different methods. First, using the assumption that patients receiving treatment improve over time, various responsiveness coefficients were calculated. Second, using change in work status as an external criterion to identify improved and nonimproved patients, Spearman's rho and receiver operating characteristic curves were calculated. Reliability was estimated from the subset of patients who reported no change in their condition over this period and expressed with the intraclass correlation coefficient and the minimal detectable change. One hundred and forty-three patient files were retrieved. The responsiveness coefficients for the Functional Rating Index were greater than for the 18-item Roland-Morris Disability Questionnaire. The intraclass correlation coefficient values for both questionnaires calculated from 96 patient files were similar, but the minimal detectable change for the Functional Rating Index was less than for the 18-item Roland-Morris Disability Questionnaire. The Functional Rating Index seems preferable to the 18-item Roland-Morris Disability Questionnaire for use in clinical trials and clinical practice.

Evaluation of the RT-LAMP and LAMP methods for detection of Mycobacterium tuberculosis.

PubMed

Wu, Dandan; Kang, Jiwen; Li, Baosheng; Sun, Dianxing

2018-05-01

The current methods for detecting Mycobacterium tuberculosis (Mtb) are not clinically optimal. Standard culture methods (SCMs) are slow, costly, or unreliable, and loop-mediated isothermal amplification (LAMP) cannot differentiate live Mtb. This study compared reverse transcription (RT)-LAMP, LAMP, and an SCM for detecting Mtb. A first experiment tested the sensitivity and specificity of primers for 9 species of Mycobacterium (H37Rv, M. intracellulare, M. marinum, M. kansasii, M. avium, M. flavescens, M. smegmatis, M. fortuitum, and M. chelonae); and 3 non-Mycobacterium species (Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae). A second experiment tested sputum specimens for the presence of Mtb, from 100 patients with tuberculosis (clinical) and 22 from patients without tuberculosis (control), using Roche solid culture (SCM), LAMP, and RT-LAMP. In the clinical samples. The rates of positivity for Mtb of the SCM, LAMP, and RT-LAMP methods were 88%, 92%, and 100%, respectively. The difference in detection rate was significant between RT-LAMP and SCM, but RT-LAMP and LAMP were comparable. In the control group, the detection rates were nil for all three methods. The specificities of the methods were similar. The sensitivity of RT-LAMP was ~10-fold higher than that of LAMP for detecting Mtb. Unlike LAMP, RT-LAMP could identify viable bacteria, and was able to detect a single copy of Mtb. Among SCM, LAMP, and RT-LAMP, the latter is the most suitable for wide use in the lower-level hospitals and clinics of China for detecting Mtb in sputum samples. © 2017 Wiley Periodicals, Inc.

Improved detection rates and treatment planning of head and neck cancer using dual-layer spectral CT.

PubMed

Lohöfer, Fabian K; Kaissis, Georgios A; Köster, Frances L; Ziegelmayer, Sebastian; Einspieler, Ingo; Gerngross, Carlos; Rasper, Michael; Noel, Peter B; Koerdt, Steffen; Fichter, Andreas; Rummeny, Ernst J; Braren, Rickmer F

2018-05-28

The aim of this study was to evaluate the advantages of dual-layer spectral CT (DLSCT) in detection and staging of head and neck cancer (HNC) as well as the imaging of tumour margins and infiltration depth compared to conventional contrast enhanced CT (CECT). Thirty-nine patients with a proven diagnosis of HNC were examined with a DLSCT scanner and retrospectively analysed. An age-matched healthy control group of the same size was used. Images were acquired in the venous phase. Virtual monoenergetic 40keV-equivalent (MonoE40) images were compared to CECT-images. Diagnostic confidence for tumour identification and margin detection was rated independently by four experienced observers. The steepness of the Hounsfield unit (HU)-increase at the tumour margin was analysed. External carotid artery branch image reconstructions were performed and their contrast compared to conventional arterial phase imaging. Means were compared using a Student's t-test. ANOVA was used for multiple comparisons. MonoE40 images were superior to CECT-images in tumour detection and margin delineation. MonoE40 showed significantly higher attenuation differences between tumour and healthy tissue compared to CECT-images (p < 0.001). The HU-increase at the boundary of the tumour was significantly steeper in MonoE40 images compared to CECT-images (p < 0.001). Iodine uptake in the tumour was significantly higher compared to healthy tissue (p < 0.001). MonoE40 compared to conventional images allowed visualisation of external carotid artery branches from the venous phase in a higher number of cases (87% vs. 67%). DLSCT enables improved detection of primary and recurrent head and neck cancer and quantification of tumour iodine uptake. Improved contrast of MonoE40 compared to conventional reconstructions enables higher diagnostic confidence concerning tumour margin detection and vessel identification. • Sensitivity concerning tumour detection are higher using dual-layer spectral-CT than conventional CT. • Lesion to background contrast in DLSCT is significantly higher than in CECT. • DLSCT provides sufficient contrast for evaluation of external carotid artery branches.

Detection of the index tumour and tumour volume in prostate cancer using T2-weighted and diffusion-weighted magnetic resonance imaging (MRI) alone.

PubMed

Rud, Erik; Klotz, Dagmar; Rennesund, Kristin; Baco, Eduard; Berge, Viktor; Lien, Diep; Svindland, Aud; Lundeby, Eskild; Berg, Rolf E; Eri, Lars M; Eggesbø, Heidi B

2014-12-01

To examine the performance of T2-weighted (T2W) and diffusion-weighted (DW) magnetic resonance imaging (MRI) for detecting the index tumour in patients with prostate cancer and to examine the agreement between MRI and histology when assessing tumour volume (TV) and overall tumour burden. The study included 199 consecutive patients with biopsy confirmed prostate cancer randomised to MRI before radical prostatectomy from December 2009 to July 2012. MRI-detected tumours (MRTs) were ranked from 1 to 3 according to decreasing volume and were compared with histologically detected tumours (HTs) ranked from 1 to 3, with HT 1 = index tumour. Whole-mount section histology was used as a reference standard. The TVs of true-positive MRTs (MRTVs 1-3) were compared with the TVs found by histology (HTVs 1-3). All tumours were registered on a 30-sector map and by classifying each sector as positive/negative, the rate of true-positive and -negative sectors was calculated. The detection rate for the HT 1 (index tumour) was 92%; HT 2, 45%; and HT 3, 37%. The MRTV 1-3 vs the HTV 1-3 were 2.8 mL vs 4.0 mL (index tumour, P < 0.001), 1.0 mL vs 0.9 mL (tumour 2, P = 0.413), and 0.6 mL vs 0.5 mL (tumour 3, P = 0.492). The rate of true-positive and -negative sectors was 50% and 88%, κ = 0.39. A combination of T2W and DW MRI detects the index tumour in 92% of cases, although MRI underestimates both TV and tumour burden compared with histology. © 2014 The Authors. BJU International © 2014 BJU International.

[Comparative analysis of 6 kinds of bacteria in the subgingival plaque in different types of patients with periodontal diseases].

PubMed

Ma, Ying-ying; Zhang, Tao-wen; Jiang, Yu-xi; Liu, Shu-tai

2015-10-01

To detect the existence of Aa,Pg,Tf,Cr,Ec and Pn in the subgingival plaque, and determine their relationships among different types of periodontal diseases. Dental plaques from 120 subjects were sampled, including 40 volunteers with health periodontal status(Group A) , forty patients with dental plaque-induced gingival diseases(Group B) and 40 patients with moderate or severe chronic periodontitis (Group C) . These samples were detected based on bacterial composition using the terminal restriction fragment length polymorphism of 16S rRNA genes by multiple-polymerase chain reaction. The data was analysed with SPSS 13.0 software package for Chi-square test. The detection rate of Pn, Cr and Pg had significant differences between group A and B. The detection rate of Ec, Cr, Pg, Aa and Tf had significant differences between group C and B. The detection rate of Ec, Pn, Cr, Pg, Aa and Tf had significant differences between group A and C. The rate of Ec, Pn, Cr, Pg and Tf detected in moderate or patients with moderate or severe chronic periodontitis are significantly higher than that in healthy subjects, indicating that these bacteria have certain correlation with chronic periodontitis. The rate of Ec, Cr, Pg and Tf detected in severe chronic periodontitis are significantly higher than that in dental-induced gingivitis, suggesting their close relationship with the progress of periodontal disease.

Evaluation of two-stage system for neutron measurement aiming at increase in count rate at Japan Atomic Energy Agency-Fusion Neutronics Source

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shinohara, K., E-mail: shinohara.koji@jaea.go.jp; Ochiai, K.; Sukegawa, A.

In order to increase the count rate capability of a neutron detection system as a whole, we propose a multi-stage neutron detection system. Experiments to test the effectiveness of this concept were carried out on Fusion Neutronics Source. Comparing four configurations of alignment, it was found that the influence of an anterior stage on a posterior stage was negligible for the pulse height distribution. The two-stage system using 25 mm thickness scintillator was about 1.65 times the count rate capability of a single detector system for d-D neutrons and was about 1.8 times the count rate capability for d-T neutrons.more » The results suggested that the concept of a multi-stage detection system will work in practice.« less

Growth of Listeria monocytogenes and Yersinia enterocolitica colonies under modified atmospheres at 4 and 8 degrees C using a model food system.

PubMed

Harrison, W A; Peters, A C; Fielding, L M

2000-01-01

The growth of Listeria monocytogenes and Yersinia enterocolitica colonies was studied on solid media at 4 and 8 degrees C under modified atmospheres (MAs) of 5% O2: 10% CO2: 85% N2 (MA1), 30% CO2: 70% N2 (MA2) and air (control). Colony radius, determined using computer image analysis, allowed specific growth rates (mu) and the time taken to detect bacterial colonies to be estimated, after colonies became visible. At 4 degrees C both MAs decreased the growth rates of L. monocytogenes by 1.5- and 3.0-fold under MA1 (mu = 0.02 h(-1)) and MA2 (mu = 0.01 h(-1)), respectively, as compared with the control (mu = 0.03 h(-1)). The time to detection of bacterial colonies was increased from 15 d (control) to 24 (MA1) and 29 d (MA2). At 8 degrees C MA2 decreased the growth rate by 1.5-fold (mu = 0.04 h(-1)) as compared with the control (mu = 0.06 h(-1)) and detection of colonies increased from 7 (control) to 9 d (MA2). At 4 degrees C both MAs decreased the growth rates of Y. enterocolitica by 1.5- and 2.5-fold under MA1 (mu = 0.03 h(-1)) and MA2 (mu = 0.02 h(-1)), respectively, as compared with the control (mu = 0.05 h(-1)). At 8 degrees C identical growth rates were obtained under MA1 and the control (mu = 0.07 h(-1)) whilst a decrease in the growth rate was obtained under MA2 (mu = 0.04 h(-1)). The detection of colonies varied from 6 (8 degrees C, aerobic) to 19 d (4 degrees C, MA2). Refrigerated modified atmosphere packaged foods should be maintained at 4 degrees C and below to ensure product safety.

Immunostimulatory oligonucleotide-induced metaphase cytogenetics detect chromosomal aberrations in 80% of CLL patients: A study of 132 CLL cases with correlation to FISH, IgVH status, and CD38 expression.

PubMed

Dicker, Frank; Schnittger, Susanne; Haferlach, Torsten; Kern, Wolfgang; Schoch, Claudia

2006-11-01

Compared with fluorescence in situ hybridization (FISH), conventional metaphase cytogenetics play only a minor prognostic role in chronic lymphocytic leukemia (CLL) so far, due to technical problems resulting from limited proliferation of CLL cells in vitro. Here, we present a simple method for in vitro stimulation of CLL cells that overcomes this limitation. In our unselected patient population, 125 of 132 cases could be successfully stimulated for metaphase generation by culture with the immunostimulatory CpG-oligonucleotide DSP30 plus interleukin 2. Of 125 cases, 101 showed chromosomal aberrations. The aberration rate is comparable to the rate detected by parallel interphase FISH. In 47 patients, conventional cytogenetics detected additional aberrations not detected by FISH analysis. A complex aberrant karyotype, defined as one having at least 3 aberrations, was detected in 30 of 125 patients, compared with only one such case as defined by FISH. Conventional cytogenetics frequently detected balanced and unbalanced translocations. A significant correlation of the poor-prognosis unmutated IgV(H) status with unbalanced translocations and of the likewise poor-prognosis CD38 expression to balanced translocations and complex aberrant karyotype was found. We demonstrate that FISH analysis underestimates the complexity of chromosomal aberrations in CLL. Therefore, conventional cytogenetics may define subgroups of patients with high risk of progression.

Automatic detection of regions of interest in mammographic images

NASA Astrophysics Data System (ADS)

Cheng, Erkang; Ling, Haibin; Bakic, Predrag R.; Maidment, Andrew D. A.; Megalooikonomou, Vasileios

2011-03-01

This work is a part of our ongoing study aimed at comparing the topology of anatomical branching structures with the underlying image texture. Detection of regions of interest (ROIs) in clinical breast images serves as the first step in development of an automated system for image analysis and breast cancer diagnosis. In this paper, we have investigated machine learning approaches for the task of identifying ROIs with visible breast ductal trees in a given galactographic image. Specifically, we have developed boosting based framework using the AdaBoost algorithm in combination with Haar wavelet features for the ROI detection. Twenty-eight clinical galactograms with expert annotated ROIs were used for training. Positive samples were generated by resampling near the annotated ROIs, and negative samples were generated randomly by image decomposition. Each detected ROI candidate was given a confidences core. Candidate ROIs with spatial overlap were merged and their confidence scores combined. We have compared three strategies for elimination of false positives. The strategies differed in their approach to combining confidence scores by summation, averaging, or selecting the maximum score.. The strategies were compared based upon the spatial overlap with annotated ROIs. Using a 4-fold cross-validation with the annotated clinical galactographic images, the summation strategy showed the best performance with 75% detection rate. When combining the top two candidates, the selection of maximum score showed the best performance with 96% detection rate.

Visually directed vs. software-based targeted biopsy compared to transperineal template mapping biopsy in the detection of clinically significant prostate cancer.

PubMed

Valerio, Massimo; McCartan, Neil; Freeman, Alex; Punwani, Shonit; Emberton, Mark; Ahmed, Hashim U

2015-10-01

Targeted biopsy based on cognitive or software magnetic resonance imaging (MRI) to transrectal ultrasound registration seems to increase the detection rate of clinically significant prostate cancer as compared with standard biopsy. However, these strategies have not been directly compared against an accurate test yet. The aim of this study was to obtain pilot data on the diagnostic ability of visually directed targeted biopsy vs. software-based targeted biopsy, considering transperineal template mapping (TPM) biopsy as the reference test. Prospective paired cohort study included 50 consecutive men undergoing TPM with one or more visible targets detected on preoperative multiparametric MRI. Targets were contoured on the Biojet software. Patients initially underwent software-based targeted biopsies, then visually directed targeted biopsies, and finally systematic TPM. The detection rate of clinically significant disease (Gleason score ≥3+4 and/or maximum cancer core length ≥4mm) of one strategy against another was compared by 3×3 contingency tables. Secondary analyses were performed using a less stringent threshold of significance (Gleason score ≥4+3 and/or maximum cancer core length ≥6mm). Median age was 68 (interquartile range: 63-73); median prostate-specific antigen level was 7.9ng/mL (6.4-10.2). A total of 79 targets were detected with a mean of 1.6 targets per patient. Of these, 27 (34%), 28 (35%), and 24 (31%) were scored 3, 4, and 5, respectively. At a patient level, the detection rate was 32 (64%), 34 (68%), and 38 (76%) for visually directed targeted, software-based biopsy, and TPM, respectively. Combining the 2 targeted strategies would have led to detection rate of 39 (78%). At a patient level and at a target level, software-based targeted biopsy found more clinically significant diseases than did visually directed targeted biopsy, although this was not statistically significant (22% vs. 14%, P = 0.48; 51.9% vs. 44.3%, P = 0.24). Secondary analysis showed similar results. Based on these findings, a paired cohort study enrolling at least 257 men would verify whether this difference is statistically significant. The diagnostic ability of software-based targeted biopsy and visually directed targeted biopsy seems almost comparable, although utility and efficiency both seem to be slightly in favor of the software-based strategy. Ongoing trials are sufficiently powered to prove or disprove these findings. Copyright © 2015 Elsevier Inc. All rights reserved.

A comparison of directed search target detection versus in-scene target detection in Worldview-2 datasets

NASA Astrophysics Data System (ADS)

Grossman, S.

2015-05-01

Since the events of September 11, 2001, the intelligence focus has moved from large order-of-battle targets to small targets of opportunity. Additionally, the business community has discovered the use of remotely sensed data to anticipate demand and derive data on their competition. This requires the finer spectral and spatial fidelity now available to recognize those targets. This work hypothesizes that directed searches using calibrated data perform at least as well as inscene manually intensive target detection searches. It uses calibrated Worldview-2 multispectral images with NEF generated signatures and standard detection algorithms to compare bespoke directed search capabilities against ENVI™ in-scene search capabilities. Multiple execution runs are performed at increasing thresholds to generate detection rates. These rates are plotted and statistically analyzed. While individual head-to-head comparison results vary, 88% of the directed searches performed at least as well as in-scene searches with 50% clearly outperforming in-scene methods. The results strongly support the premise that directed searches perform at least as well as comparable in-scene searches.

Microscopic Examination of Gallbladder Stones Improves Rate of Detection of Clonorchis sinensis Infection

PubMed Central

Ma, Rui-hong; Luo, Xiao-bing; Zheng, Pei-ming; Luo, Zhen-liang; Yang, Liu-qing

2013-01-01

To improve the rate of detection of Clonorchis sinensis infection, we compared different specimens from patients with cholecystolithiasis. Feces, gallbladder bile, and gallbladder stones collected from 179 consecutive patients with cholecystolithiasis underwent microscopic examination, and according to the results, 30 egg-positive and 30 egg-negative fecal, gallbladder bile, and gallbladder stone specimens, respectively, underwent real-time fluorescent PCR. The detection rates of eggs in feces, bile, and gallbladder stones were 30.7%, 44.7%, and 69.8%, respectively, and the differences were statistically significant (P < 0.01). The PCR results confirmed that the eggs in the specimens were C. sinensis eggs. Eggs in the feces were “fresh” and in the gallbladder stones were “old.” Microscopic examination of gallbladder stones may improve the detection rates of C. sinensis infection, which is important for developing individualized treatments to prevent the recurrence of gallbladder stones and to prevent the occurrence of severe liver damage and cholangiocarcinoma. PMID:23698535

Impact of cap-assisted colonoscopy on the learning curve and quality in colonoscopy: a randomized controlled trial.

PubMed

Tang, Zhouwen; Zhang, Daniel S; Thrift, Aaron P; Patel, Kalpesh K

2018-03-01

Colonoscopy competency assessment in trainees traditionally has been informal. Comprehensive metrics such as the Assessment of Competency in Endoscopy (ACE) tool suggest that competency thresholds are higher than assumed. Cap-assisted colonoscopy (CAC) may improve competency, but data regarding novice trainees are lacking. We compared CAC versus standard colonoscopy (SC) performed by novice trainees in a randomized controlled trial. All colonoscopies performed by 3 gastroenterology fellows without prior experience were eligible for the study. Exclusion criteria included patient age <18 or >90 years, pregnancy, prior colon resection, diverticulitis, colon obstruction, severe hematochezia, referral for EMR, or a procedure done without patient sedation. Patients were randomized to either CAC or SC in a 1:1 fashion. The primary outcome was the independent cecal intubation rate (ICIR). Secondary outcomes were cecal intubation time, polyp detection rate, polyp miss rate, adenoma detection rate, ACE tool scores, and cumulative summation learning curves. A total of 203 colonoscopies were analyzed, 101 in CAC and 102 in SC. CAC resulted in a significantly higher cecal intubation rate, at 79.2% in CAC compared with 66.7% in SC (P = .04). Overall cecal intubation time was significantly shorter at 13.7 minutes for CAC versus 16.5 minutes for SC (P =.02). Cecal intubation time in the case of successful independent fellow intubation was not significantly different between CAC and SC (11.6 minutes vs 12.7 minutes; P = .29). Overall ACE tool motor and cognitive scores were higher with CAC. Learning curves for ICIR approached the competency threshold earlier with cap use but reached competency for only 1 fellow. The polyp detection rate, polyp miss rate, and adenoma detection rate were not significantly different between groups. CAC resulted in significant improvement in ICIR, overall ACE tool scores, and trend toward competency on learning curves when compared with SC in colonoscopy trainees without prior colonoscopy experience. (Clinical trial registration number: NCT02472730.). Copyright © 2018 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

The role of 99Tcm-HMPAO brain SPET in paediatric traumatic brain injury.

PubMed

Goshen, E; Zwas, S T; Shahar, E; Tadmor, R

1996-05-01

Twenty-eight paediatric patients suffering from chronic sequelae of traumatic brain injury (TBI) were examined by EEG, radionuclide imaging with 99Tcm-hexamethylpropyleneamine oxime (99Tcm-HMPAO), computed tomography (CT) and, when available, magnetic resonance imaging (MRI), the results of which were evaluated retrospectively. Our findings indicate that neuro-SPET (single photon emission tomography) with 99Tcm-HMPAO is more sensitive than morphological or electrophysiological tests in detecting functional lesions. In our group, 15 of 32 CT scans were normal, compared with 3 of 35 SPET studies. SPET identified approximately 2.5 times more lesions than CT (86 vs 34). SPET was found to be particularly sensitive in detecting organic abnormalities in the basal ganglia and cerebellar regions, with a 3.6:1 detection rate in the basal ganglia and a 5:1 detection rate in the cerebellum compared with CT. In conclusion, neuro-SPET appears to be very useful when evaluating paediatric post-TBI patients in whom other modalities are not successful.

Effect of mental stress on cold pain in chronic tension-type headache sufferers.

PubMed

Cathcart, Stuart; Winefield, Anthony H; Lushington, Kurt; Rolan, Paul

2009-10-01

Mental stress is a noted contributing factor in chronic tension-type headache (CTH), however the mechanisms underlying this are not clearly understood. One proposition is that stress aggravates already increased pain sensitivity in CTH sufferers. This hypothesis could be partially tested by examining effects of mental stress on threshold and supra-threshold experimental pain processing in CTH sufferers. Such studies have not been reported to date. The present study measured pain detection and tolerance thresholds and ratings of supra-threshold pain stimulation from cold pressor test in CTH sufferers (CTH-S) and healthy Control (CNT) subjects exposed to a 60-min stressful mental task, and in CTH sufferers exposed to a 60-min neutral condition (CTH-N). Headache sufferers had lower pain tolerance thresholds and increased pain intensity ratings compared to controls. Pain detection and tolerance thresholds decreased and pain intensity ratings increased during the stress task, with a greater reduction in pain detection threshold and increase in pain intensity ratings in the CTH-S compared to CNT group. The results support the hypothesis that mental stress contributes to CTH through aggravating already increased pain sensitivity in CTH sufferers.

Sampling of the anterior apical region results in increased cancer detection and upgrading in transrectal repeat saturation biopsy of the prostate.

PubMed

Seles, Maximilian; Gutschi, Thomas; Mayrhofer, Katrin; Fischereder, Katja; Ehrlich, Georg; Gallé, Guenter; Gutschi, Stefan; Pachernegg, Oliver; Pummer, Karl; Augustin, Herbert

2016-04-01

To evaluate whether biopsy cores taken via a transrectal approach from the anterior apical region of the prostate in a repeat-biopsy population can result in an increased overall cancer detection rate and in more accurate assessment of the Gleason score. The study was a prospective, randomised (end-fire vs side-fire ultrasound probe) evaluation of 288 men by repeat transrectal saturation biopsy with 28 cores taken from the transition zone, base, mid-lobar, anterior and the anterior apical region located ventro-laterally to the urethra of the peripheral zone. The overall prostate cancer detection rate was 44.4%. Improvement of the overall detection rate by 7.8% could be achieved with additional biopsies of the anterior apical region. Two tumours featuring a Gleason score 7 could only be detected in the anterior apical region. In three cases (2.34%) Gleason score upgrading was achieved by separate analysis of each positive core of the anterior apical region. A five-fold higher cancer detection rate in the anterior apical region compared with the transition zone could be shown. Sampling of the anterior apical region results in higher overall cancer detection rate in repeat transrectal saturation biopsies of the prostate. Specimens from this region can detect clinically significant cancer, improve accuracy of the Gleason Scoring and therefore may alter therapy. © 2015 The Authors BJU International © 2015 BJU International Published by John Wiley & Sons Ltd.

Role of Magnetic Resonance Imaging in Prostate Cancer Screening: A Pilot Study Within the Göteborg Randomised Screening Trial

PubMed Central

Bergdahl, Anna Grenabo; Wilderäng, Ulrica; Aus, Gunnar; Carlsson, Sigrid; Damber, Jan-Erik; Frånlund, Maria; Geterud, Kjell; Khatami, Ali; Socratous, Andreas; Stranne, Johan; Hellström, Mikael; Hugosson, Jonas

2016-01-01

Background Magnetic resonance imaging (MRI) and targeted biopsies (TB) have shown potential to more accurately detect significant prostate cancer (PC) compared to prostate-specific antigen (PSA) and systematic biopsies (SB). Objective To compare sequential screening (PSA + MRI) with conventional PSA screening. Design, Setting and Participants Of 384 attendees in the 10th screening round of the Göteborg randomised screening trial, 124 men, median age 69.5, had a PSA of ≥1.8 ng/ml and underwent a prebiopsy MRI. Men with suspicious lesions on MRI and/or PSA ≥3.0 ng/ml were referred for biopsy. SB was performed blinded to MRI results and TB was performed in men with tumour-suspicious findings on MRI. Three screening strategies were compared (PSA≥3.0+SB; PSA≥3.0+MRI+TB and PSA≥1.8+MRI+TB). Outcome Measurements and Statistical Analysis Cancer detection rates, sensitivity and specificity were calculated per screening strategy and compared using McNemar´s test. Results and Limitations In total, 28 PC were detected, of which 20 were diagnosed in biopsy-naïve men. Both PSA≥3.0+MRI and PSA≥1.8+MRI significantly increased specificity compared with PSA≥3.0+SB (0.92 and 0.79 vs. 0.52; p<0.002 for both), while sensitivity was significantly higher for PSA≥1.8+MRI compared with PSA>=3.0+MRI (0.73 vs. 0.46, p=0.008). The detection rate of significant cancer was higher with PSA≥1.8+MRI compared to PSA≥3.0+SB (5.9 vs. 4.0%), while the detection rate of insignificant cancer was lowered by PSA≥3.0+MRI (0.3 vs. 1.2%). The primary limitation of this study is the small sample of men. Conclusion A screening strategy with a lowered PSA cut-off followed by TB in MRI-positive men seems to increase the detection of significant cancers while improving specificity. If replicated, these results may contribute to a paradigm shift in future screening. Patient Summary Major concerns in prostate-specific antigen screening are overdiagnosis and underdiagnosis. We evaluated whether prostate magnetic resonance imaging could improve the balance of benefits to harm in prostate cancer screening, and we found promising potential of using magnetic resonance imaging in addition to prostate-specific antigen. PMID:26724840

Drop-Off Detection with the Long Cane: Effects of Different Cane Techniques on Performance

ERIC Educational Resources Information Center

Kim, Dae Shik; Emerson, Robert Wall; Curtis, Amy

2009-01-01

This study compared the drop-off detection performance with the two-point touch and constant contact cane techniques using a repeated-measures design with a convenience sample of 15 cane users with visual impairments. The constant contact technique was superior to the two-point touch technique in the drop-off detection rate and the 50% detection…

Feature selection and classifier parameters estimation for EEG signals peak detection using particle swarm optimization.

PubMed

Adam, Asrul; Shapiai, Mohd Ibrahim; Tumari, Mohd Zaidi Mohd; Mohamad, Mohd Saberi; Mubin, Marizan

2014-01-01

Electroencephalogram (EEG) signal peak detection is widely used in clinical applications. The peak point can be detected using several approaches, including time, frequency, time-frequency, and nonlinear domains depending on various peak features from several models. However, there is no study that provides the importance of every peak feature in contributing to a good and generalized model. In this study, feature selection and classifier parameters estimation based on particle swarm optimization (PSO) are proposed as a framework for peak detection on EEG signals in time domain analysis. Two versions of PSO are used in the study: (1) standard PSO and (2) random asynchronous particle swarm optimization (RA-PSO). The proposed framework tries to find the best combination of all the available features that offers good peak detection and a high classification rate from the results in the conducted experiments. The evaluation results indicate that the accuracy of the peak detection can be improved up to 99.90% and 98.59% for training and testing, respectively, as compared to the framework without feature selection adaptation. Additionally, the proposed framework based on RA-PSO offers a better and reliable classification rate as compared to standard PSO as it produces low variance model.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Poels, Kenneth, E-mail: kenneth.poels@uzbrussel.be; Verellen, Dirk; Van de Vondel, Iwein

Purpose: Because frame rates on current clinical available electronic portal imaging devices (EPID’s) are limited to 7.5 Hz, a new commercially available PerkinElmer EPID (XRD 1642 AP19) with a maximum frame rate of 30 Hz and a new scintillator (Kyokko PI200) with improved sensitivity (light output) for megavolt (MV) irradiation was evaluated. In this work, the influence of MV pulse artifacts and pulsing artifact suppression techniques on fiducial marker and marker-less detection of a lung lesion was investigated, because target localization is an important component of uncertainty in geometrical verification of real-time tumor tracking. Methods: Visicoil™ markers with a diametermore » of 0.05 and 0.075 cm were used for MV marker tracking with a frame rate of, respectively, 7.5, 15, and 30 Hz. A 30 Hz readout of the detector was obtained by a 2 × 2 pixel binning, reducing spatial resolution. Static marker detection was conducted in function of increasing phantom thickness. Additionally, marker-less tracking was conducted and compared with the ground-truth fiducial marker motion. Performance of MV target detection was investigated by comparing the least-square sine wave fit of the detected marker positions with the predefined sine wave motion. For fiducial marker detection, a Laplacian-of-Gaussian enhancement was applied after which normalized cross correlation was used to find the most probable marker position. Marker-less detection was performed by using the scale and orientation adaptive mean shift tracking algorithm. For each MV fluoroscopy, a free running (FR-nF) (ignoring MV pulsing during readout) acquisition mode was compared with two acquisition modes intending to reduce MV pulsing artifacts, i.e., combined wavelet-FFT filtering (FR-wF) and electronic readout synchronized with respect to MV pulses. Results: A 0.05 cm Visicoil marker resulted in an unacceptable root-mean square error (RMSE) > 0.2 cm with a maximum frame rate of 30 Hz during FR-nF readout. With a 30 Hz synchronized readout (S-nF) and during 15 Hz readout (independent of readout mode), RMSE was submillimeter for a static 0.05 cm Visicoil. A dynamic 0.05 cm Visicoil was not detectable on the XRD 1642 AP19, despite a fast synchronized readout. For a 0.075 cm Visicoil, deviations of sine wave motion were submillimeter (RMSE < 0.08 cm), independent of the acquisition mode (FR, S). For marker-less tumor detection, FR-nF images resulted in RMSE > 0.3 cm, while for MV fluoroscopy in S-mode RMSE < 0.1 cm for 15 Hz and RMSE < 0.16 cm for 30 Hz. Largest consistency in target localization was experienced during 15 Hz S-nF readout. Conclusions: In general, marker contrast decreased in function of higher frame rates, which was detrimental for marker detection success. In this work, Visicoils with a thickness of 0.075 cm were showing best results for a 15 Hz frame rate, while non-MV compatible 0.05 cm Visicoil markers were not visible on the new EPID with improved sensitivity compared to EPID models based on a Kodak Lanex Fast scintillator. No noticeable influence of pulsing artifacts on the detection of a 0.075 cm Visicoil was observed, while a synchronized readout provided most reliable detection of a marker-less soft-tissue structure.« less

Breast screening using 2D-mammography or integrating digital breast tomosynthesis (3D-mammography) for single-reading or double-reading--evidence to guide future screening strategies.

PubMed

Houssami, Nehmat; Macaskill, Petra; Bernardi, Daniela; Caumo, Francesca; Pellegrini, Marco; Brunelli, Silvia; Tuttobene, Paola; Bricolo, Paola; Fantò, Carmine; Valentini, Marvi; Ciatto, Stefano

2014-07-01

We compared detection measures for breast screening strategies comprising single-reading or double-reading using standard 2D-mammography or 2D/3D-mammography, based on the 'screening with tomosynthesis or standard mammography' (STORM) trial. STORM prospectively examined screen-reading in two sequential phases, 2D-mammography alone and integrated 2D/3D-mammography, in asymptomatic women participating in Trento and Verona (Northern Italy) population-based screening services. Outcomes were ascertained from assessment and/or excision histology or follow-up. For each screen-reading strategy we calculated the number of detected and non-detected (including interval) cancers, cancer detection rates (CDRs), false positive recall (FPR) measures and incremental CDR relative to a comparator strategy. We estimated the false:true positive (FP:TP) ratio and sensitivity of each mammography screening strategy. Paired binary data were compared using McNemar's test. Amongst 7292 screening participants, there were 65 (including six interval) breast cancers; estimated first-year interval cancer rate was 0.82/1000 screens (95% confidence interval (CI): 0.30-1.79/1000). For single-reading, 35 cancers were detected at both 2D and 2D/3D-mammography, 20 cancers were detected only with 2D/3D-mammography compared with none at 2D-mammography alone (p<0.001) and 10 cancers were not detected. For double-reading, 39 cancers were detected at 2D-mammography and 2D/3D-mammography, 20 were detected only with 2D/3D-mammography compared with none detected at 2D-mammography alone (p<0.001) and six cancers were not detected. The incremental CDR attributable to 2D/3D-mammography (versus 2D-mammography) of 2.7/1000 screens (95% CI: 1.6-4.2) was evident for single and for double-reading. Incremental CDR attributable to double-reading (versus single-reading) of 0.55/1000 screens (95% CI: -0.02-1.4) was evident for 2D-mammography and for 2D/3D-mammography. Estimated FP:TP ratios showed that 2D/3D-mammography screening strategies had more favourable FP to TP trade-off and higher sensitivity, applying single-reading or double-reading, relative to 2D-mammography screening. The evidence we report warrants rethinking of breast screening strategies and should be used to inform future evaluations of 2D/3D-mammography that assess whether or not the estimated incremental detection translates into improved screening outcomes such as a reduction in interval cancer rates. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

A randomised tandem colonoscopy trial of narrow band imaging versus white light examination to compare neoplasia miss rates.

PubMed

Kaltenbach, T; Friedland, S; Soetikno, R

2008-10-01

Colonoscopy, the "gold standard" screening test for colorectal cancer (CRC), has known diagnostic limitations. Advances in endoscope technology have focused on improving mucosal visualisation. In addition to increased angle of view and resolution features, recent colonoscopes have non-white-light optics, such as narrow band imaging (NBI), to enhance image contrast. We aimed to study the neoplasia diagnostic characteristics of NBI, by comparing the neoplasm miss rate when the colonoscopy was performed under NBI versus white light (WL). Randomised controlled trial. US Veterans hospital. Elective colonoscopy adults. We randomly assigned patients to undergo a colonoscopic examination using NBI or WL. All patients underwent a second examination using WL, as the reference standard. The primary end point was the difference in the neoplasm miss rate, and secondary outcome was the neoplasm detection rate. In 276 tandem colonoscopy patients, there was no significant difference of miss or detection rates between NBI or WL colonoscopy techniques. Of the 135 patients in the NBI group, 17 patients (12.6%; 95% confidence interval (CI) 7.5 to 19.4%) had a missed neoplasm, as compared with 17 of the 141 patients (12.1%; 95% CI 7.2 to 18.6%) in the WL group, with a miss rate risk difference of 0.5% (95% CI -7.2 to 8.3). 130 patients (47%) had at least one neoplasm. Missed lesions with NBI showed similar characteristics to those missed with WL. All missed neoplasms were tubular adenomas, the majority (78%) was < or = 5 mm and none were larger than 1 cm (one-sided 95% CI up to 1%). Nonpolypoid lesions represented 35% (13/37) of missed neoplasms. NBI did not improve the colorectal neoplasm miss rate compared to WL; the miss rate for advanced adenomas was less than 1% and for all adenomas was 12%. The neoplasm detection rates were similar high using NBI or WL; almost a half the study patients had at least one adenoma. Clinicaltrials.gov identifier: NCT00628147.

Routine vs extended outpatient EEG for the detection of interictal epileptiform discharges

PubMed Central

Britton, Jeffrey W.; Rajasekaran, Vijayalakshmi; Fabris, Rachel R.; Cherian, Perumpillichira J.; Kelly-Williams, Kristen M.; So, Elson L.; Nickels, Katherine C.; Wong-Kisiel, Lily C.; Lagerlund, Terrence D.; Cascino, Gregory D.; Worrell, Gregory A.; Wirrell, Elaine C.

2016-01-01

Objective: To compare the yield of epileptiform abnormalities on 30-minute recordings with those greater than 45 minutes. Methods: We performed a prospective observational cross-sectional study of all outpatient routine EEGs comparing the rate of interictal epileptiform discharges (IEDs) and clinical events during the initial 30 minutes (routine) with those occurring in the remaining 30–60 minutes (extended). A relative increase of 10% was considered clinically significant. Results: EEGs from 1,803 patients were included; overall EEG duration was 59.4 minutes (SD ±6.5). Of 426 patients with IEDs at any time during the EEG, 81 (19.1%, 95% confidence interval 15.6–23) occurred only after the initial 30 minutes. The rate of late IEDs was not associated with age, indication, IED type, or sleep deprivation. Longer recording times also increased event capture rate by approximately 30%. Conclusions: The yield of IED and event detection is increased in extended outpatient EEGs compared to 30-minute studies. PMID:26984946

Routine vs extended outpatient EEG for the detection of interictal epileptiform discharges.

PubMed

Burkholder, David B; Britton, Jeffrey W; Rajasekaran, Vijayalakshmi; Fabris, Rachel R; Cherian, Perumpillichira J; Kelly-Williams, Kristen M; So, Elson L; Nickels, Katherine C; Wong-Kisiel, Lily C; Lagerlund, Terrence D; Cascino, Gregory D; Worrell, Gregory A; Wirrell, Elaine C

2016-04-19

To compare the yield of epileptiform abnormalities on 30-minute recordings with those greater than 45 minutes. We performed a prospective observational cross-sectional study of all outpatient routine EEGs comparing the rate of interictal epileptiform discharges (IEDs) and clinical events during the initial 30 minutes (routine) with those occurring in the remaining 30-60 minutes (extended). A relative increase of 10% was considered clinically significant. EEGs from 1,803 patients were included; overall EEG duration was 59.4 minutes (SD ±6.5). Of 426 patients with IEDs at any time during the EEG, 81 (19.1%, 95% confidence interval 15.6-23) occurred only after the initial 30 minutes. The rate of late IEDs was not associated with age, indication, IED type, or sleep deprivation. Longer recording times also increased event capture rate by approximately 30%. The yield of IED and event detection is increased in extended outpatient EEGs compared to 30-minute studies. © 2016 American Academy of Neurology.

Trends in Detection of Invasive Cancer and Ductal Carcinoma In Situ at Biennial Screening Mammography in Spain: A Retrospective Cohort Study

PubMed Central

Román, Marta; Rué, Montse; Sala, Maria; Ascunce, Nieves; Baré, Marisa; Baroja, Araceli; De la Vega, Mariola; Galcerán, Jaume; Natal, Carmen; Salas, Dolores; Sánchez-Jacob, Mercedes; Zubizarreta, Raquel; Castells, Xavier

2013-01-01

Background Breast cancer incidence has decreased in the last decade, while the incidence of ductal carcinoma in situ (DCIS) has increased substantially in the western world. The phenomenon has been attributed to the widespread adaption of screening mammography. The aim of the study was to evaluate the temporal trends in the rates of screen detected invasive cancers and DCIS, and to compare the observed trends with respect to hormone replacement therapy (HRT) use along the same study period. Methods Retrospective cohort study of 1,564,080 women aged 45–69 years who underwent 4,705,681 screening mammograms from 1992 to 2006. Age-adjusted rates of screen detected invasive cancer, DCIS, and HRT use were calculated for first and subsequent screenings. Poisson regression was used to evaluate the existence of a change-point in trend, and to estimate the adjusted trends in screen detected invasive breast cancer and DCIS over the study period. Results The rates of screen detected invasive cancer per 100.000 screened women were 394.0 at first screening, and 229.9 at subsequent screen. The rates of screen detected DCIS per 100.000 screened women were 66.8 at first screen and 43.9 at subsequent screens. No evidence of a change point in trend in the rates of DCIS and invasive cancers over the study period were found. Screen detected DCIS increased at a steady 2.5% per year (95% CI: 1.3; 3.8), while invasive cancers were stable. Conclusion Despite the observed decrease in breast cancer incidence in the population, the rates of screen detected invasive cancer remained stable during the study period. The proportion of DCIS among screen detected breast malignancies increased from 13% to 17% throughout the study period. The rates of screen detected invasive cancer and DCIS were independent of the decreasing trend in HRT use observed among screened women after 2002. PMID:24376649

Decreased growth rate of P. falciparum blood stage parasitemia with age in a holoendemic population.

PubMed

Pinkevych, Mykola; Petravic, Janka; Chelimo, Kiprotich; Vulule, John; Kazura, James W; Moormann, Ann M; Davenport, Miles P

2014-04-01

In malaria holoendemic settings, decreased parasitemia and clinical disease is associated with age and cumulative exposure. The relative contribution of acquired immunity against various stages of the parasite life cycle is not well understood. In particular, it is not known whether changes in infection dynamics can be best explained by decreasing rates of infection, or by decreased growth rates of parasites in blood. Here, we analyze the dynamics of Plasmodium falciparum infection after treatment in a cohort of 197 healthy study participants of different ages. We use both polymerase chain reaction (PCR) and microscopy detection of parasitemia in order to understand parasite growth rates and infection rates over time. The more sensitive PCR assay detects parasites earlier than microscopy, and demonstrates a higher overall prevalence of infection than microscopy alone. The delay between PCR and microscopy detection is significantly longer in adults compared with children, consistent with slower parasite growth with age. We estimated the parasite multiplication rate from delay to PCR and microscopy detections of parasitemia. We find that both the delay between PCR and microscopy infection as well as the differing reinfection dynamics in different age groups are best explained by a slowing of parasite growth with age.

Clinical evaluation of endoscopic trimodal imaging for the detection and differentiation of colonic polyps.

PubMed

van den Broek, Frank J C; Fockens, Paul; Van Eeden, Susanne; Kara, Mohammed A; Hardwick, James C H; Reitsma, Johannes B; Dekker, Evelien

2009-03-01

Endoscopic trimodal imaging (ETMI) incorporates high-resolution endoscopy (HRE) and autofluorescence imaging (AFI) for adenoma detection, and narrow-band imaging (NBI) for differentiation of adenomas from nonneoplastic polyps. The aim of this study was to compare AFI with HRE for adenoma detection and to assess the diagnostic accuracy of NBI for differentiation of polyps. This was a randomized trial of tandem colonoscopies. The study was performed at the Academic Medical Center in Amsterdam. One hundred patients underwent colonoscopy with ETMI. Each colonic segment was examined twice for polyps, once with HRE and once with AFI, in random order per patient. All detected polyps were assessed with NBI for pit pattern and with AFI for color, and subsequently removed. Histopathology served as the gold standard for diagnosis. The main outcome measures of this study were adenoma miss-rates of AFI and HRE, and diagnostic accuracy of NBI and AFI for differentiating adenomas from nonneoplastic polyps. Among 50 patients examined with AFI first, 32 adenomas were detected initially. Subsequent inspection with HRE identified 8 additional adenomas. Among 50 patients examined with HRE first, 35 adenomas were detected initially. Successive AFI yielded 14 additional adenomas. The adenoma miss-rates of AFI and HRE therefore were 20% and 29%, respectively (P = .351). The sensitivity, specificity, and overall accuracy of NBI for differentiation were 90%, 70%, and 79%, respectively; corresponding figures for AFI were 99%, 35%, and 63%, respectively. The overall adenoma miss-rate was 25%; AFI did not significantly reduce the adenoma miss-rate compared with HRE. Both NBI and AFI had a disappointing diagnostic accuracy for polyp differentiation, although AFI had a high sensitivity.

Detection of hypoglycemia with continuous interstitial and traditional blood glucose monitoring using the FreeStyle Navigator Continuous Glucose Monitoring System.

PubMed

McGarraugh, Geoffrey; Bergenstal, Richard

2009-03-01

The objective of the analysis was to compare detection of hypoglycemic episodes (glucose <70 mg/dL lasting >15 min) with the FreeStyle Navigator Continuous Glucose Monitoring System (FSN-CGM) (Abbott Diabetes Care, Alameda, CA) alarms to detection with traditional finger stick testing at an average frequency of eight tests per day. The performance of FSN-CGM alarms was evaluated in a clinic setting using 58 subjects with type 1 diabetes mellitus (T1DM) monitoring interstitial glucose concentration over a 5-day period compared to reference YSI measurements (instrument manufactured by YSI, Yellow Springs, OH) at 15-min intervals. Finger stick glucose testing was evaluated in the home environment with 91 subjects with TIDM monitoring with the blood glucose meter integrated into the FreeStyle Navigator (FSN-BG) over a 20-day period. The reference was FSN-CGM with results masked from the subjects. Blood glucose values <=85 mg/dL were considered the optimal treatment level to avoid or reverse hypoglycemia. With a threshold alarm setting of 85 mg/dL, 90.6% of hypoglycemic episodes were detected within +/- 30 min by FSN-CGM in the clinic study. When the alarm was activated, YSI glucose was <= 85 mg/dL 77.2% of the time. In the home environment, the average FSN-BG testing frequency was 7.9 tests per day. Hypoglycemia was verified within +/- 30 min by FSN-BG measurements <= 85 mg/dL at a rate of 27.5%. Even with a high rate of FSN-BG testing, hypoglycemia detected by FSN-CGM was verified by patients with T1DM very infrequently. A high rate of hypoglycemia detection with a moderate rate of unnecessary alarms can be attained using FSN-CGM.

Next-generation narrow band imaging system for colonic polyp detection: a prospective multicenter randomized trial.

PubMed

Horimatsu, Takahiro; Sano, Yasushi; Tanaka, Shinji; Kawamura, Takuji; Saito, Shoichi; Iwatate, Mineo; Oka, Shiro; Uno, Koji; Yoshimura, Kenichi; Ishikawa, Hideki; Muto, Manabu; Tajiri, Hisao

2015-07-01

Previous studies have yielded conflicting results on the colonic polyp detection rate with narrow-band imaging (NBI) compared with white-light imaging (WLI). We compared the mean number of colonic polyps detected per patient for NBI versus WLI using a next-generation NBI system (EVIS LUCERA ELITE; Olympus Medical Systems) used with standard-definition (SD) colonoscopy and wide-angle (WA) colonoscopy. this study is a 2 × 2 factorial, prospective, multicenter randomized controlled trial. this study was conducted at five academic centers in Japan. patients were allocated to one of four groups: (1) WLI with SD colonoscopy (H260AZI), (2) NBI with SD colonoscopy (H260AZI), (3) WLI with WA colonoscopy (CF-HQ290), and (4) NBI with WA colonoscopy (CF-HQ290). the mean numbers of polyps detected per patient were compared between the four groups: WLI with/without WA colonoscopy and NBI with/without WA colonoscopy. Of the 454 patients recruited, 431 patients were enrolled. The total numbers of polyps detected by WLI with SD, NBI with SD, WLI with WA, and NBI with WA were 164, 176, 188, and 241, respectively. The mean number of polyps detected per patient was significantly higher in the NBI group than in the WLI group (2.01 vs 1.56; P = 0.032). The rate was not higher in the WA group than in the SD group (1.97 vs 1.61; P = 0.089). Although WA colonoscopy did not improve the polyp detection, next-generation NBI colonoscopy represents a significant improvement in the detection of colonic polyps.

[Spectral analysis of Heart Rate Variability in psychiatric patients: autonomic nervous system evaluation in psychotic, anxiety and depressive disorders].

PubMed

Lo Turco, Giovanni; Grimaldi Di Terresena, Liria

2012-01-01

The aim of this study was to test the primary hypothesis of altered Heart Rate Variability (HRV) and heart rate in a sample of patients with mental disorders and the secondary hypothesis of normalization of HRV values as a result of clinical improvement. The study was conducted on a sample of 90 patients with psychotic, anxiety and mood disorders. Each patient was subjected to detection of HRV and heart rate via a photoplethysmographic sensor and evaluated with rating scales based on the specific disorder. The parameters detected in the sample were compared with a control group of healthy subjects. There were no significant differences of cardiac autonomic modulation between the group of patients in whom is possible exclude the drug influence and the control group; significantly lower values of HRV parameters in the group of patients with drug influence, and especially in subgroup of psychotic patients, compared to controls, are, instead, detected. The study also shows a significant increase in heart rate as a common feature in mental disorders, regardless of treatment. Clinical improvement appears to promote the normalization of the variability in patients with high DS of tachogram. The study suggests a potential increased risk of cardiovascular mortality in patients, as evidenced by the increased values of heart rate, regardless of drug treatment. This risk is even more pronounced in psychotic patients in drug treatment because of the simultaneous significant reduction of HRV parameters.

Interferon Gamma-Based Detection of Latent Tuberculosis Infection in the Border States of Nuevo Leon and Tamaulipas, Mexico

PubMed Central

Oren, Eyal; Alatorre-Izaguirre, Gabriela; Vargas-Villarreal, Javier; Moreno-Treviño, Maria Guadalupe; Garcialuna-Martinez, Javier; Gonzalez-Salazar, Francisco

2015-01-01

Nearly one-third of the world’s population is infected with latent tuberculosis (LTBI). Tuberculosis (TB) rates in the border states are higher than national rates in both the US and Mexico, with the border accounting for 30% of total registered TB cases in both countries. However, LTBI rates in the general population in Mexican border states are unknown. In this region, LTBI is diagnosed using the tuberculin skin test (TST). New methods of detection more specific than TST have been developed, although there is currently no gold standard for LTBI detection. Our objective is to demonstrate utility of the Quantiferon TB gold In-Tube (QFT-GIT) test compared with the TST to detect LTBI among border populations. This is an observational, cross-sectional study carried out in border areas of the states of Nuevo Leon and Tamaulipas, Mexico. Participants (n = 210) provided a TST and blood sample for the QFT-GIT. Kappa coefficients assessed the agreement between TST and QFT-GIT. Participant characteristics were compared using Fisher exact tests. Thirty-eight percent of participants were diagnosed with LTBI by QFT-GIT. The proportion of LTBI detected using QFT-GIT was almost double [38% (79/210)] that found by TST [19% (39/210)] (P < 0.001). Concordance between TST and QFT-GIT was low (kappa = 0.37). We recommend further studies utilizing the QFT-GIT test to detect LTBI among border populations. PMID:26484340

Interferon Gamma-Based Detection of Latent Tuberculosis Infection in the Border States of Nuevo Leon and Tamaulipas, Mexico.

PubMed

Oren, Eyal; Alatorre-Izaguirre, Gabriela; Vargas-Villarreal, Javier; Moreno-Treviño, Maria Guadalupe; Garcialuna-Martinez, Javier; Gonzalez-Salazar, Francisco

2015-01-01

Nearly one-third of the world's population is infected with latent tuberculosis (LTBI). Tuberculosis (TB) rates in the border states are higher than national rates in both the US and Mexico, with the border accounting for 30% of total registered TB cases in both countries. However, LTBI rates in the general population in Mexican border states are unknown. In this region, LTBI is diagnosed using the tuberculin skin test (TST). New methods of detection more specific than TST have been developed, although there is currently no gold standard for LTBI detection. Our objective is to demonstrate utility of the Quantiferon TB gold In-Tube (QFT-GIT) test compared with the TST to detect LTBI among border populations. This is an observational, cross-sectional study carried out in border areas of the states of Nuevo Leon and Tamaulipas, Mexico. Participants (n = 210) provided a TST and blood sample for the QFT-GIT. Kappa coefficients assessed the agreement between TST and QFT-GIT. Participant characteristics were compared using Fisher exact tests. Thirty-eight percent of participants were diagnosed with LTBI by QFT-GIT. The proportion of LTBI detected using QFT-GIT was almost double [38% (79/210)] that found by TST [19% (39/210)] (P < 0.001). Concordance between TST and QFT-GIT was low (kappa = 0.37). We recommend further studies utilizing the QFT-GIT test to detect LTBI among border populations.

A reference standard-based quality assurance program for radiology.

PubMed

Liu, Patrick T; Johnson, C Daniel; Miranda, Rafael; Patel, Maitray D; Phillips, Carrie J

2010-01-01

The authors have developed a comprehensive radiology quality assurance (QA) program that evaluates radiology interpretations and procedures by comparing them with reference standards. Performance metrics are calculated and then compared with benchmarks or goals on the basis of published multicenter data and meta-analyses. Additional workload for physicians is kept to a minimum by having trained allied health staff members perform the comparisons of radiology reports with the reference standards. The performance metrics tracked by the QA program include the accuracy of CT colonography for detecting polyps, the false-negative rate for mammographic detection of breast cancer, the accuracy of CT angiography detection of coronary artery stenosis, the accuracy of meniscal tear detection on MRI, the accuracy of carotid artery stenosis detection on MR angiography, the accuracy of parathyroid adenoma detection by parathyroid scintigraphy, the success rate for obtaining cortical tissue on ultrasound-guided core biopsies of pelvic renal transplants, and the technical success rate for peripheral arterial angioplasty procedures. In contrast with peer-review programs, this reference standard-based QA program minimizes the possibilities of reviewer bias and erroneous second reviewer interpretations. The more objective assessment of performance afforded by the QA program will provide data that can easily be used for education and management conferences, research projects, and multicenter evaluations. Additionally, such performance data could be used by radiology departments to demonstrate their value over nonradiology competitors to referring clinicians, hospitals, patients, and third-party payers. Copyright 2010 American College of Radiology. Published by Elsevier Inc. All rights reserved.

Evaluation of copy number variation detection for a SNP array platform

PubMed Central

2014-01-01

Background Copy Number Variations (CNVs) are usually inferred from Single Nucleotide Polymorphism (SNP) arrays by use of some software packages based on given algorithms. However, there is no clear understanding of the performance of these software packages; it is therefore difficult to select one or several software packages for CNV detection based on the SNP array platform. We selected four publicly available software packages designed for CNV calling from an Affymetrix SNP array, including Birdsuite, dChip, Genotyping Console (GTC) and PennCNV. The publicly available dataset generated by Array-based Comparative Genomic Hybridization (CGH), with a resolution of 24 million probes per sample, was considered to be the “gold standard”. Compared with the CGH-based dataset, the success rate, average stability rate, sensitivity, consistence and reproducibility of these four software packages were assessed compared with the “gold standard”. Specially, we also compared the efficiency of detecting CNVs simultaneously by two, three and all of the software packages with that by a single software package. Results Simply from the quantity of the detected CNVs, Birdsuite detected the most while GTC detected the least. We found that Birdsuite and dChip had obvious detecting bias. And GTC seemed to be inferior because of the least amount of CNVs it detected. Thereafter we investigated the detection consistency produced by one certain software package and the rest three software suits. We found that the consistency of dChip was the lowest while GTC was the highest. Compared with the CNVs detecting result of CGH, in the matching group, GTC called the most matching CNVs, PennCNV-Affy ranked second. In the non-overlapping group, GTC called the least CNVs. With regards to the reproducibility of CNV calling, larger CNVs were usually replicated better. PennCNV-Affy shows the best consistency while Birdsuite shows the poorest. Conclusion We found that PennCNV outperformed the other three packages in the sensitivity and specificity of CNV calling. Obviously, each calling method had its own limitations and advantages for different data analysis. Therefore, the optimized calling methods might be identified using multiple algorithms to evaluate the concordance and discordance of SNP array-based CNV calling. PMID:24555668

Impact of the Addition of Digital Breast Tomosynthesis (DBT) to Standard 2D Digital Screening Mammography on the Rates of Patient Recall, Cancer Detection, and Recommendations for Short-term Follow-up.

PubMed

Powell, Jaclynn L; Hawley, Jeffrey R; Lipari, Adele M; Yildiz, Vedat O; Erdal, B Selnur; Carkaci, Selin

2017-03-01

The addition of digital breast tomosynthesis (DBT) to digital screening mammography (DM) has been shown to decrease recall rates and improve cancer detection rates, but there is a lack of data regarding the impact of DBT on rates of short-term follow-up. We assessed possible changes in performance measures with the introduction of DBT at our facility. In our observational study, databases were used to compare rates of recall, short-term follow-up, biopsy, and cancer detection between women undergoing DM without (n = 10,477) and women undergoing DM with (n = 2304) the addition of DBT. Regression analysis was performed to determine associations with patient age, breast density, and availability of comparison examinations. The addition of DBT resulted in significantly lower recall rates (16%-14%, P = .017), higher rates of biopsy (12.7%-19.1%, P < .01), and increased detection of ductal carcinoma in situ, with a difference of 2.3 cases per 1000 screens (P = .044). A 33% increase in cancer detection rates was observed with DBT, which did not reach statistical significance. Short-term follow-up of probably benign findings was 80% higher in the DBT group (odds ratio = 1.80, 95% confidence interval = 1.38-2.36, P < .001). To our knowledge, we are the first to study the impact of DBT on rates of short-term follow-up, and observed an 80% increase over the DM group. Further research is needed to determine the malignancy rate of Breast Imaging Reporting and Data System 3 lesions detected with DBT, and establish appropriate follow-up to maximize cancer detection while minimizing expense and patient anxiety. Copyright © 2017 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

Sentinel lymph node mapping in endometrial cancer: comparison of fluorescence dye with traditional radiocolloid and blue.

PubMed

Papadia, Andrea; Gasparri, Maria Luisa; Buda, Alessandro; Mueller, Michael D

2017-10-01

Sentinel lymph node (SLN) mapping in endometrial cancer (EMCA) is rapidly gaining acceptance in the clinical community. As compared to a full lymphadenectomy in every patient, to a selective lymphadenectomy after frozen section of uterus in selected patients with intrauterine risk factors or to a strategy in which a lymphadenectomy is always omitted, SLN mapping seems to be a reasonable and oncologically safe middle ground. Various protocols can be used when applying an SLN mapping. In this manuscript we review the characteristics, toxicity and clinical impact of technetium-99m radiocolloid (Tc-99m), of the blue dyes (methylene blue, isosulfan blue and patent blue) and of indocyanine green (ICG). ICG has an excellent toxicity profile, has higher overall and bilateral detection rates as compared to blue dyes and higher bilateral detection rates as compared to a combination of Tc-99m and blue dye. The detrimental effect of BMI on the detection rates is attenuated when ICG is used as a tracer. The ease of use of the ICG SLN mapping is perceived by the patients as a better quality of care delivered. Whenever possible, ICG should be favored over the other tracers for SLN mapping in EMCA patients.

From Conventional Radiotracer Tc-99(m) with Blue Dye to Indocyanine Green Fluorescence: A Comparison of Methods Towards Optimization of Sentinel Lymph Node Mapping in Early Stage Cervical Cancer for a Laparoscopic Approach.

PubMed

Buda, Alessandro; Papadia, Andrea; Zapardiel, Ignacio; Vizza, Enrico; Ghezzi, Fabio; De Ponti, Elena; Lissoni, Andrea Alberto; Imboden, Sara; Diestro, Maria Dolores; Verri, Debora; Gasparri, Maria Luisa; Bussi, Beatrice; Di Martino, Giampaolo; de la Noval, Begoña Diaz; Mueller, Michael; Crivellaro, Cinzia

2016-09-01

The credibility of sentinel lymph node (SLN) mapping is becoming increasingly more established in cervical cancer. We aimed to assess the sensitivity of SLN biopsy in terms of detection rate and bilateral mapping in women with cervical cancer by comparing technetium-99 radiocolloid (Tc-99(m)) and blue dye (BD) versus fluorescence mapping with indocyanine green (ICG). Data of patients with cervical cancer stage 1A2 to 1B1 from 5 European institutions were retrospectively reviewed. All centers used a laparoscopic approach with the same intracervical dye injection. Detection rate and bilateral mapping of ICG were compared, respectively, with results obtained by standard Tc-99(m) with BD. Overall, 76 (53 %) of 144 of women underwent preoperative SLN mapping with radiotracer and intraoperative BD, whereas 68 of (47 %) 144 patients underwent mapping using intraoperative ICG. The detection rate of SLN mapping was 96 % and 100 % for Tc-99(m) with BD and ICG, respectively. Bilateral mapping was achieved in 98.5 % for ICG and 76.3 % for Tc-99(m) with BD; this difference was statistically significant (p < 0.0001). The fluorescence SLN mapping with ICG achieved a significantly higher detection rate and bilateral mapping compared to standard radiocolloid and BD technique in women with early stage cervical cancer. Nodal staging with an intracervical injection of ICG is accurate, safe, and reproducible in patients with cervical cancer. Before replacing lymphadenectomy completely, the additional value of fluorescence SLN mapping on both perioperative morbidity and survival should be explored and confirmed by ongoing controlled trials.

Comparison of Abbott RealTime High-Risk HPV and Hybrid Capture 2 Assays for Detection of HPV Infection.

PubMed

Ko, Kiwoong; Yu, Shinae; Lee, Eun Hee; Park, Hyosoon; Woo, Hee-Yeon; Kwon, Min-Jung

2016-09-01

Various assays for detecting high-risk human papillomavirus (HR HPV) have been introduced recently, including the Abbott RealTime High-Risk HPV assay. We sought to compare the performance of Abbott PCR to Hybrid Capture 2 for the detection of HR HPV. A total of 941 cervical swab specimens were obtained. We submitted all specimens for HR HPV detection with HC2 and Abbott PCR, and then additionally analyzed discordant and concordant positive results using restriction fragment mass polymorphism (RFMP) genotyping analysis. HC2 detected one of 13 HR HPV types in 12.3% (116/941) of cases, while Abbott PCR detected one of 14 detectable HR HPV types in 12.9% (121/941) of cases. The overall agreement rate was 97.3% with a kappa coefficient of 0.879. Discordant results between these two assays were observed in 25 cases. HC2 showed a sensitivity of 90.0% and specificity of 95.9%, while Abbott PCR showed a sensitivity of 98.0% and specificity of 96.8% when using RFMP results as the gold standard. For HPV 16/18 detection, Abbott PCR showed 95.8%/88.9% sensitivity and 99.2%/99.8% specificity, respectively. The overall coinfection rate between HPV 16, 18 and non-16/18 was 9.9% (12/121) in Abbott PCR analysis. Considering its high agreement rate with HC2, higher sensitivity/specificity compared to HC2, and ability to differentiate HPV 16/18 from other HPV types, Abbott PCR could be a reliable laboratory testing method for the screening of HPV infections. © 2016 by the Association of Clinical Scientists, Inc.

Upper limits on the rates of BNS and NSBH mergers from Advanced LIGO's first observing run

NASA Astrophysics Data System (ADS)

Lackey, Benjamin; LIGO Collaboration

2017-01-01

Last year the Advanced LIGO detectors finished their first observing run and detected two binary black hole mergers with high significance but no binary neutron star (BNS) or neutron-star-black-hole (NSBH) mergers. We present upper limits on the rates of BNS and NSBH mergers in the universe based on their non-detection with two modeled searches. With zero detections, the upper limits depend on the choice of prior, but we find 90% upper limits using a conservative prior of 12 , 000 / Gpc3 / yr for BNS mergers and 1 , 000 - 3 , 000 / Gpc3 / yr for NSBH mergers depending on the black hole mass. Comparing these upper limits to several rates predictions in the literature, we find our upper limits are close to the more optimistic rates estimates. Further non-detections in the second and third observing runs should be able to rule out several rates predictions. Using the observed rate of short gamma ray bursts (GRBs), we can also place lower limits on the average beaming angle of short GRBs. Assuming all short GRBs come from BNS mergers, we find a 90% lower limit of 1-4 degrees on the GRB beaming angle, with the range coming from the uncertainty in short GRB rates.

[Comparison of screening performance between primary high-risk HPV screening and high-risk HPV screening plus liquid-based cytology cotesting in diagnosis of cervical precancerous or cancerous lesions].

PubMed

Zhao, X L; Remila, Rezhake; Hu, S Y; Zhang, L; Xu, X Q; Chen, F; Pan, Q J; Zhang, X; Zhao, F H

2018-05-06

Objective: To evaluate and compare the screening performance of primary high-risk HPV(HR-HPV) screening and HR-HPV screening plus liquid-based cytology (LBC) cotesting in diagnosis of cervical cancer and precancerous lesions (CIN2+). Methods: We pooled 17 population-based cross-sectional studies which were conducted across China from 1999 to 2008. After obtaining informed consent, all women received liquid-based cytology(LBC)testing, HR-HPV DNA testing. Totally 28 777 women with complete LBC, HPV and biopsy results were included in the final analysis. Screening performance of primary HR-HPV DNA screening and HPV screening plus LBC co-testing in diagnosis of CIN2+ were calculated and compared among different age groups. Results: Among the whole population, the detection rates of primary HR-HPV screening and HR-HPV screening plus LBC co-testing are 3.05% (879 CIN2+) and 3.13%(900 CIN2+), respectively. The sensitivity were 96.4% and 98.7% (χ(2)=19.00, P< 0.001), and the specificity were 86.2% and 78.8% (χ(2)=2 067.00, P< 0.001), respectively. Areas under the receiver operating characteristic (ROC) curve (AUC) showed that the primary HR-HPV screening performed better than co-testing (AUC were 0.913 and 0.888; Z= 6.16, P< 0.001). Compared with primary HR-HPV screening, co-testing showed significantly higher colposcopy referral rates (16.5% and 23.6%, respectively, χ(2)=132.00, P< 0.001) and the number of colposcopy examination for detecting per CIN2+ (5.4 and 7.6, respectively).In the group aged 25-29, the colposcopy referral rates was 8.7 (10.9%(199 cases) vs 1.3%(23 cases)) times as much as the detection rate of primary HR-HPV screening in diagnosis of CIN2+, and was 12.5 (15.7%(288 cases) vs 1.3%(23 cases)) times as much as the detection rate of HR-HPV screening plus cytology contesting. Conclusion: Compared with primary HR-HPV screening, HR-HPV screening plus cytology co-testing does not show better results in the screening performance for CIN2+ detection, and the cost-effectiveness is not good enough, especially in younger age group.

Towards Development of a 3-State Self-Paced Brain-Computer Interface

PubMed Central

Bashashati, Ali; Ward, Rabab K.; Birch, Gary E.

2007-01-01

Most existing brain-computer interfaces (BCIs) detect specific mental activity in a so-called synchronous paradigm. Unlike synchronous systems which are operational at specific system-defined periods, self-paced (asynchronous) interfaces have the advantage of being operational at all times. The low-frequency asynchronous switch design (LF-ASD) is a 2-state self-paced BCI that detects the presence of a specific finger movement in the ongoing EEG. Recent evaluations of the 2-state LF-ASD show an average true positive rate of 41% at the fixed false positive rate of 1%. This paper proposes two designs for a 3-state self-paced BCI that is capable of handling idle brain state. The two proposed designs aim at detecting right- and left-hand extensions from the ongoing EEG. They are formed of two consecutive detectors. The first detects the presence of a right- or a left-hand movement and the second classifies the detected movement as a right or a left one. In an offline analysis of the EEG data collected from four able-bodied individuals, the 3-state brain-computer interface shows a comparable performance with a 2-state system and significant performance improvement if used as a 2-state BCI, that is, in detecting the presence of a right- or a left-hand movement (regardless of the type of movement). It has an average true positive rate of 37.5% and 42.8% (at false positives rate of 1%) in detecting right- and left-hand extensions, respectively, in the context of a 3-state self-paced BCI and average detection rate of 58.1% (at false positive rate of 1%) in the context of a 2-state self-paced BCI. PMID:18288260

Low-complexity R-peak detection in ECG signals: a preliminary step towards ambulatory fetal monitoring.

PubMed

Rooijakkers, Michiel; Rabotti, Chiara; Bennebroek, Martijn; van Meerbergen, Jef; Mischi, Massimo

2011-01-01

Non-invasive fetal health monitoring during pregnancy has become increasingly important. Recent advances in signal processing technology have enabled fetal monitoring during pregnancy, using abdominal ECG recordings. Ubiquitous ambulatory monitoring for continuous fetal health measurement is however still unfeasible due to the computational complexity of noise robust solutions. In this paper an ECG R-peak detection algorithm for ambulatory R-peak detection is proposed, as part of a fetal ECG detection algorithm. The proposed algorithm is optimized to reduce computational complexity, while increasing the R-peak detection quality compared to existing R-peak detection schemes. Validation of the algorithm is performed on two manually annotated datasets, the MIT/BIH Arrhythmia database and an in-house abdominal database. Both R-peak detection quality and computational complexity are compared to state-of-the-art algorithms as described in the literature. With a detection error rate of 0.22% and 0.12% on the MIT/BIH Arrhythmia and in-house databases, respectively, the quality of the proposed algorithm is comparable to the best state-of-the-art algorithms, at a reduced computational complexity.

The role of the human papillomavirus in the pathogenesis of Schneiderian inverted papillomas: an analytic overview of the evidence.

PubMed

Lawson, William; Schlecht, Nicolas F; Brandwein-Gensler, Margaret

2008-06-01

Evidence of an etiological role for human papillomavirus (HPV) in Schneiderian inverted papillomas IP arose in the late 1980's; yet almost three decades later, the association between HPV and IP has yet to be universally accepted. This is probably due to the disparate HPV detection rates in IP reported in the literature. We analyzed the weight of published data in order to address the following questions: why do the HPV detection rates in IP vary so greatly? What is the relationship between low-risk (LR) and high-risk (HR) HPV types and HPV detection rates in IP? Is there a relationship between the presence and type of HPV in IP and recurrence and malignant progression? A search using the Pubmed search engine was performed to identify studies published in English from 01/87 through 12/06 using the MeSH terms ''HPV'' and ''Inverted", "Exophytic", "Oncocytic Schneiderian" or "Fungiform papilloma''. Data was abstracted from publications including histology, HPV target, HPV type, method of detection, etc. HPV results were stratified by histology and other variables. Tests for heterogeneity (between-study variability) were conducted, and weighted prevalence (WP) estimates and 95% confidence intervals (CI) were calculated using a random-effects inverse-variance model stratified on study. The association between HPV IP recurrence was estimated by random-effects inverse-variance weighted odds ratio (OR). Weighted estimates revealed similar detection rates across detection methods, 26.8% (95%CI 16.4-37.2%) by ISH, 25.2% (95%CI 14.7-35.6%) by consensus PCR, and 23.6% (95%CI 12.2-35.0%) by type-specific PCR. A preponderance of HPV 6/11 is found in IP as compared to HPV 16/18; the overall unadjusted ratio of LR to high-risk HR HPV types is 2.8:1 The HPV detection rates significantly increase (Wald t-test P < 0.02) in IPs with high-grade dysplasia (WP 55.8%, 95%CI 30.5-81.0%) and carcinoma (WP 55.1%, 95%CI 37.0-73.2%) as compared to IPs with no dysplasia or mild dysplasia (WP 22.3%, 95%CI 15.9-28.6%). Furthermore, the preponderance of LR HPV in benign IP (ratio LR/HR = 4.8:1) shifts in dysplastic and malignant IP. The LR/HR ratio is 1.1:1 for IPs with high-grade dysplasias, this ratio is inverted to favor HR HPV (1:2.4) for malignant IP. Recurrences developed in 44 of 236 patients; HPV was detected in 27 of 44 IPs (WP 57.9%, 95%CI 31.6-84.2%) that developed recurrences and in 24 of 192 IPs (WP 9.7%, 95%CI 4.4-15.0%) that did not develop recurrence. The presence of HPV was significantly associated with the likelihood of developing recurrence (weighted OR of 10.2, 95%CI 3.2-32.8). We hypothesize that LR HPV may induce IP formation, and then are lost as infected cells are shed, as a "hit and run" phenomenon. HPV detection rates increase in dysplastic IP and SCC-ex-IP with increasing ratio of HR to LR HPV types, compared to nondysplastic IP. We believe that one explanation for the variation in HPV detection rates between different studies may be the actual histologic composition of the cohort. That is, if one series contains a higher frequency of dysplastic and malignant IP, it may have a higher detection rate than another series which contains only nondysplastic IP. We hypothesize that the higher rates of HPV detection in dysplastic and malignant IP may be related to HPV integration. The implication of this is that HPV sub-type testing may identify patients at risk for recurrence, or progression to dysplasia and malignancy, and thus may impact surveillance protocols.

Advances in Magnetic Resonance Imaging Contrast Agents for Biomarker Detection

PubMed Central

Sinharay, Sanhita; Pagel, Mark D.

2016-01-01

Recent advances in magnetic resonance imaging (MRI) contrast agents have provided new capabilities for biomarker detection through molecular imaging. MRI contrast agents based on the T2 exchange mechanism have more recently expanded the armamentarium of agents for molecular imaging. Compared with T1 and T2* agents, T2 exchange agents have a slower chemical exchange rate, which improves the ability to design these MRI contrast agents with greater specificity for detecting the intended biomarker. MRI contrast agents that are detected through chemical exchange saturation transfer (CEST) have even slower chemical exchange rates. Another emerging class of MRI contrast agents uses hyperpolarized 13C to detect the agent with outstanding sensitivity. These hyperpolarized 13C agents can be used to track metabolism and monitor characteristics of the tissue microenvironment. Together, these various MRI contrast agents provide excellent opportunities to develop molecular imaging for biomarker detection. PMID:27049630

Permeation of 70% isopropyl alcohol through surgical gloves: comparison of the standard methods ASTM F739 and EN 374.

PubMed

Mäkelä, Erja A; Vainiotalo, Sinikka; Peltonen, Kimmo

2003-06-01

Standard test methods ASTM F739 and EN 374 were compared by assessing the permeation of 70% isopropyl alcohol (2-propanol) through seven brands of surgical gloves. The two standards differ in the flow rates of the collection medium and in the chemical permeation rate at which the breakthrough time (BTT) is detected, the EN detection level being 10 times higher than the permeation rate used by ASTM. In a departure from the EN standard method, a 4 h testing time was used instead of 8 h. All of the tested gloves were from the same manufacturer and were made from either natural rubber (NR) (six brands) or chloroprene rubber (CR) (one brand). Two of the NR glove brands were double layered. For the thin NR gloves (0.22, 0.28 and 0.27 mm) the permeation rates were higher throughout the tests with a flow rate of 474 ml/min (EN) of the collection medium (nitrogen) compared with the permeation rates obtained with a flow rate of 52 ml/min (ASTM). These resulted in BTTs of 4.6, 6.5 and 7.6 min (EN) and 4.8, 6.5 and 9.1 min (ASTM), respectively. No statistical difference could be observed between the BTT values obtained with the two standard methods for any of the thin gloves. Thus, although the ASTM standard has a lower criterion for the detection of permeation, it does not necessarily produce shorter BTTs. For the better barriers the methods yielded more equivalent permeation rate curves and thus the EN BTTs were longer than the ASTM BTTs: the EN results were 21, 80, 122 and >240 min compared with the ASTM results of 12, 32, 38 and 103 min for glove thicknesses of 0.37 (NR), 0.22 + 0.22 (double layered NR), 0.31 + 0.29 (double layered NR) and 0.19 mm (CR), respectively.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, K.; Itow, Y.; Rott, C., E-mail: koun@stelab.nagoya-u.ac.jp, E-mail: rott@skku.edu, E-mail: itow@stelab.nagoya-u.ac.jp

Dark matter could be captured in the Sun and self-annihilate, giving rise to an observable neutrino flux. Indirect searches for dark matter looking for this signal with neutrino telescopes have resulted in tight constraints on the interaction cross-section of dark matter with ordinary matter. We investigate how robust limits are against astro-physical uncertainties. We study the effect of the velocity distribution of dark matter in our Galaxy on capture rates in the Sun. We investigate four sources of uncertainties: orbital speed of the Sun, escape velocity of dark matter from the halo, dark matter velocity distribution functions and existence ofmore » a dark disc. We find that even extreme cases currently discussed do not decrease the sensitivity of indirect detection significantly because the capture is achieved over a broad range of the velocity distribution by integration over the velocity distribution. The effect of the uncertainty in the high-velocity tail of dark matter halo is very marginal as the capture process is rather inefficient at this region. The difference in capture rate in the Sun for various scenarios is compared to the expected change in event rates for direct detection. The possibility of co-rotating structure with the Sun can largely boost the signal and hence makes the interpretation of indirect detection conservative compared to direct detection.« less

Detection of Clostridium difficile infection clusters, using the temporal scan statistic, in a community hospital in southern Ontario, Canada, 2006-2011.

PubMed

Faires, Meredith C; Pearl, David L; Ciccotelli, William A; Berke, Olaf; Reid-Smith, Richard J; Weese, J Scott

2014-05-12

In hospitals, Clostridium difficile infection (CDI) surveillance relies on unvalidated guidelines or threshold criteria to identify outbreaks. This can result in false-positive and -negative cluster alarms. The application of statistical methods to identify and understand CDI clusters may be a useful alternative or complement to standard surveillance techniques. The objectives of this study were to investigate the utility of the temporal scan statistic for detecting CDI clusters and determine if there are significant differences in the rate of CDI cases by month, season, and year in a community hospital. Bacteriology reports of patients identified with a CDI from August 2006 to February 2011 were collected. For patients detected with CDI from March 2010 to February 2011, stool specimens were obtained. Clostridium difficile isolates were characterized by ribotyping and investigated for the presence of toxin genes by PCR. CDI clusters were investigated using a retrospective temporal scan test statistic. Statistically significant clusters were compared to known CDI outbreaks within the hospital. A negative binomial regression model was used to identify associations between year, season, month and the rate of CDI cases. Overall, 86 CDI cases were identified. Eighteen specimens were analyzed and nine ribotypes were classified with ribotype 027 (n = 6) the most prevalent. The temporal scan statistic identified significant CDI clusters at the hospital (n = 5), service (n = 6), and ward (n = 4) levels (P ≤ 0.05). Three clusters were concordant with the one C. difficile outbreak identified by hospital personnel. Two clusters were identified as potential outbreaks. The negative binomial model indicated years 2007-2010 (P ≤ 0.05) had decreased CDI rates compared to 2006 and spring had an increased CDI rate compared to the fall (P = 0.023). Application of the temporal scan statistic identified several clusters, including potential outbreaks not detected by hospital personnel. The identification of time periods with decreased or increased CDI rates may have been a result of specific hospital events. Understanding the clustering of CDIs can aid in the interpretation of surveillance data and lead to the development of better early detection systems.

Automatic Brain Tumor Detection in T2-weighted Magnetic Resonance Images

NASA Astrophysics Data System (ADS)

Dvořák, P.; Kropatsch, W. G.; Bartušek, K.

2013-10-01

This work focuses on fully automatic detection of brain tumors. The first aim is to determine, whether the image contains a brain with a tumor, and if it does, localize it. The goal of this work is not the exact segmentation of tumors, but the localization of their approximate position. The test database contains 203 T2-weighted images of which 131 are images of healthy brain and the remaining 72 images contain brain with pathological area. The estimation, whether the image shows an afflicted brain and where a pathological area is, is done by multi resolution symmetry analysis. The first goal was tested by five-fold cross-validation technique with 100 repetitions to avoid the result dependency on sample order. This part of the proposed method reaches the true positive rate of 87.52% and the true negative rate of 93.14% for an afflicted brain detection. The evaluation of the second part of the algorithm was carried out by comparing the estimated location to the true tumor location. The detection of the tumor location reaches the rate of 95.83% of correct anomaly detection and the rate 87.5% of correct tumor location.

Contributing to the early detection of Rett syndrome: the potential role of auditory Gestalt perception.

PubMed

Marschik, Peter B; Einspieler, Christa; Sigafoos, Jeff

2012-01-01

To assess whether there are qualitatively deviant characteristics in the early vocalizations of children with Rett syndrome, we had 400 native Austrian-German speakers listen to audio recordings of vocalizations from typically developing girls and girls with Rett syndrome. The audio recordings were rated as (a) inconspicuous, (b) conspicuous or (c) not able to decide between (a) and (b). The results showed that participants were accurate in differentiating the vocalizations of typically developing children compared to children with Rett syndrome. However, the accuracy for rating verbal behaviors was dependent on the type of vocalization with greater accuracy for canonical babbling compared to cooing vocalizations. The results suggest a potential role for the use of rating child vocalizations for early detection of Rett syndrome. This is important because clinical criteria related to speech and language development remain important for early identification of Rett syndrome. Copyright © 2011 Elsevier Ltd. All rights reserved.

First Application of 7-T Magnetic Resonance Imaging in Endoscopic Endonasal Surgery of Skull Base Tumors.

PubMed

Barrett, Thomas F; Dyvorne, Hadrien A; Padormo, Francesco; Pawha, Puneet S; Delman, Bradley N; Shrivastava, Raj K; Balchandani, Priti

2017-07-01

Successful endoscopic endonasal surgery for the resection of skull base tumors is reliant on preoperative imaging to delineate pathology from the surrounding anatomy. The increased signal-to-noise ratio afforded by 7-T MRI can be used to increase spatial and contrast resolution, which may lend itself to improved imaging of the skull base. In this study, we apply a 7-T imaging protocol to patients with skull base tumors and compare the images with clinical standard of care. Images were acquired at 7 T on 11 patients with skull base lesions. Two neuroradiologists evaluated clinical 1.5-, 3-, and 7-T scans for detection of intracavernous cranial nerves and internal carotid artery (ICA) branches. Detection rates were compared. Images were used for surgical planning and uploaded to a neuronavigation platform and used to guide surgery. Image analysis yielded improved detection rates of cranial nerves and ICA branches at 7 T. The 7-T images were successfully incorporated into preoperative planning and intraoperative neuronavigation. Our study represents the first application of 7-T MRI to the full neurosurgical workflow for endoscopic endonasal surgery. We detected higher rates of cranial nerves and ICA branches at 7-T MRI compared with 3- and 1.5-T MRI, and found that integration of 7 T into surgical planning and guidance was feasible. These results suggest a potential for 7-T MRI to reduce surgical complications. Future studies comparing standardized 7-, 3-, and 1.5-T MRI protocols in a larger number of patients are warranted to determine the relative benefit of 7-T MRI for endonasal endoscopic surgical efficacy. Copyright © 2017 Elsevier Inc. All rights reserved.

First Application of 7T Magnetic Resonance Imaging in Endoscopic Endonasal Surgery of Skull Base Tumors

PubMed Central

Barrett, Thomas F; Dyvorne, Hadrien A; Padormo, Francesco; Pawha, Puneet S; Delman, Bradley N; Shrivastava, Raj K; Balchandani, Priti

2018-01-01

Background Successful endoscopic endonasal surgery for the resection of skull base tumors is reliant on preoperative imaging to delineate pathology from the surrounding anatomy. The increased signal-to-noise ratio afforded by 7T MRI can be used to increase spatial and contrast resolution, which may lend itself to improved imaging of skull base. In this study, we apply a 7T imaging protocol to patients with skull base tumors and compare the images to clinical standard of care. Methods Images were acquired at 7T on 11 patients with skull base lesions. Two neuroradiologists evaluated clinical 1.5T, 3T, and 7T scans for detection of intracavernous cranial nerves and ICA branches. Detection rates were compared. Images were utilized for surgical planning and uploaded to a neuronavigation platform and used to guide surgery. Results Image analysis yielded improved detection rates of cranial nerves and ICA branches at 7T. 7T images were successfully incorporated into preoperative planning and intraoperative neuronavigation. Conclusion Our study represents the first application of 7T MRI to the full neurosurgical workflow for endoscopic endonasal surgery. We detected higher rates of cranial nerves and ICA branches at 7T MRI compared to 3T and 1.5 T, and found that integration of 7T into surgical planning and guidance was feasible. These results suggest a potential for 7T MRI to reduce surgical complications. Future studies comparing standardized 7T, 3T, and 1.5 T MRI protocols in a larger number of patients are warranted to determine the relative benefit of 7T MRI for endonasal endoscopic surgical efficacy. PMID:28359922

[Comparative analysis between diatom nitric acid digestion method and plankton 16S rDNA PCR method].

PubMed

Han, Jun-ge; Wang, Cheng-bao; Li, Xing-biao; Fan, Yan-yan; Feng, Xiang-ping

2013-10-01

To compare and explore the application value of diatom nitric acid digestion method and plankton 16S rDNA PCR method for drowning identification. Forty drowning cases from 2010 to 2011 were collected from Department of Forensic Medicine of Wenzhou Medical University. Samples including lung, kidney, liver and field water from each case were tested with diatom nitric acid digestion method and plankton 16S rDNA PCR method, respectively. The Diatom nitric acid digestion method and plankton 16S rDNA PCR method required 20 g and 2 g of each organ, and 15 mL and 1.5 mL of field water, respectively. The inspection time and detection rate were compared between the two methods. Diatom nitric acid digestion method mainly detected two species of diatoms, Centriae and Pennatae, while plankton 16S rDNA PCR method amplified a length of 162 bp band. The average inspection time of each case of the Diatom nitric acid digestion method was (95.30 +/- 2.78) min less than (325.33 +/- 14.18) min of plankton 16S rDNA PCR method (P < 0.05). The detection rates of two methods for field water and lung were both 100%. For liver and kidney, the detection rate of plankton 16S rDNA PCR method was both 80%, higher than 40% and 30% of diatom nitric acid digestion method (P < 0.05), respectively. The laboratory testing method needs to be appropriately selected according to the specific circumstances in the forensic appraisal of drowning. Compared with diatom nitric acid digestion method, plankton 16S rDNA PCR method has practice values with such advantages as less quantity of samples, huge information and high specificity.

Heart rate detection from an electronic weighing scale.

PubMed

González-Landaeta, R; Casas, O; Pallàs-Areny, R

2008-08-01

We propose a novel technique for beat-to-beat heart rate detection based on the ballistocardiographic (BCG) force signal from a subject standing on a common electronic weighing scale. The detection relies on sensing force variations related to the blood acceleration in the aorta, works even if wearing footwear and does not require any sensors attached to the body because it uses the load cells in the scale. We have devised an approach to estimate the sensitivity and frequency response of three commercial weighing scales to assess their capability to detect the BCG force signal. Static sensitivities ranged from 490 nV V(-1) N(-1) to 1670 nV V(-1) N(-1). The frequency response depended on the subject's mass but it was broad enough for heart rate estimation. We have designed an electronic pulse detection system based on off-the-shelf integrated circuits to sense heart-beat-related force variations of about 0.24 N. The signal-to-noise ratio of the main peaks of the force signal detected was higher than 30 dB. A Bland-Altman plot was used to compare the RR time intervals estimated from the ECG and BCG force signals for 17 volunteers. The error was +/-21 ms, which makes the proposed technique suitable for short-term monitoring of the heart rate.

Clinical outcomes of prostate cancer patients in Yokosuka City, Japan: A comparative study between cases detected by prostate-specific antigen-based screening in Yokosuka and those detected by other means.

PubMed

Sakai, Naoki; Taguri, Masataka; Kobayashi, Kazuki; Noguchi, Sumio; Ikeda, Shigeru; Koh, Hideshige; Satomi, Yoshiaki; Furuhata, Akihiko

2015-08-01

To investigate whether prostate-specific antigen-based screening reduced the prostate cancer mortality rate in Yokosuka, Japan. We carried out a cohort study, in which we compared clinical outcomes between patients detected by prostate-specific antigen-based screening (S group n = 524) versus those detected by other means (NS group n = 1044). Clinical and pathological factors were evaluated using Cox regression analyses and the Kaplan-Meier method. A total of 1.5% (8/524) of patients in the S group and 6.7% (70/1044) of those in the NS group died from prostate cancer during follow up. A total of 8.0% (42/524) of patients in the S group and 11.4% (119/1044) in the NS group died from other causes. The 10-year cancer specific survival rates of the S and NS groups were 97% and 86%, respectively (P < 0.001). The median age was significantly lower in the S group than the NS group: 71 and 73 years, respectively (P < 0.001). The rate of Gleason score 8-10 was significantly lower in the S group than the NS group: 9.7% and 16.7%, respectively (P < 0.001). The rate of patients with metastasis or prostate-specific antigen 100 ng/mL or more was significantly lower in the S group than the NS group: 7.8% and 23.0%, respectively (P < 0.001). On multivariate analysis, Gleason score 8-10 compared with Gleason score 6 was independently associated with cancer-specific survival (hazard ratio 4.808, 95% confidence interval 1.044-22.14, P = 0.044). Prostate-specific antigen-based population screening in Yokosuka City might help to reduce the prostate cancer mortality rate. © 2015 The Japanese Urological Association.

The effect of exercise on venous gas emboli and decompression sickness in human subjects at 4.3 psia

NASA Technical Reports Server (NTRS)

Conkin, Johnny; Waligora, James M.; Horrigan, David J., Jr.; Hadley, Arthur T., III

1987-01-01

The contribution of upper body exercise to altitude decompression sickness while at 4.3 psia after 3.5 or 4.0 hours of 100% oxygen prebreathing at 14.7 psia was determined by comparing the incidence and patterns of venous gas emboli (VGE), and the incidence of Type 1 decompression sickness (DCS) in 43 exercising male subjects and 9 less active male Doppler Technicians (DT's). Each subject exercised for 4 minutes at each of 3 exercise stations while at 4.3 psia. An additional 4 minutes were spent monitoring for VGE by the DT while the subject was supine on an examination cot. In the combined 3.5 and 4.0 hour oxygen prebreathe data, 13 subjects complained of Type 1 DCS compared to 9 complaints from DT's. VGE were detected in 28 subjects compared to 14 detections from DT's. A chi-square analysis of proportions showed no statistically significantly difference in the incidence of Type 1 DCS or VGE between the two groups; however, the average time to detect VGE and to report Tyep 1 DCS symptoms were statistically different. It was concluded that 4 to 6 hours of upper body exercise at metabolic rates simulating EVA metabolic rates hastens the initial detection of VGE and the time to report Type 1 DCS symptoms as compared to DT's.

A Biological Signal-Based Stress Monitoring Framework for Children Using Wearable Devices.

PubMed

Choi, Yerim; Jeon, Yu-Mi; Wang, Lin; Kim, Kwanho

2017-08-23

The safety of children has always been an important issue, and several studies have been conducted to determine the stress state of a child to ensure the safety. Audio signals and biological signals including heart rate are known to be effective for stress state detection. However, collecting those data requires specialized equipment, which is not appropriate for the constant monitoring of children, and advanced data analysis is required for accurate detection. In this regard, we propose a stress state detection framework which utilizes both audio signal and heart rate collected from wearable devices, and adopted machine learning methods for the detection. Experiments using real-world data were conducted to compare detection performances across various machine learning methods and noise levels of audio signal. Adopting the proposed framework in the real-world will contribute to the enhancement of child safety.

Extended range radiation dose-rate monitor

DOEpatents

Valentine, Kenneth H.

1988-01-01

An extended range dose-rate monitor is provided which utilizes the pulse pileup phenomenon that occurs in conventional counting systems to alter the dynamic response of the system to extend the dose-rate counting range. The current pulses from a solid-state detector generated by radiation events are amplified and shaped prior to applying the pulses to the input of a comparator. The comparator generates one logic pulse for each input pulse which exceeds the comparator reference threshold. These pulses are integrated and applied to a meter calibrated to indicate the measured dose-rate in response to the integrator output. A portion of the output signal from the integrator is fed back to vary the comparator reference threshold in proportion to the output count rate to extend the sensitive dynamic detection range by delaying the asymptotic approach of the integrator output toward full scale as measured by the meter.

Detection of depression in acute schizophrenia: sensitivity and specificity of 2 standard observer rating scales.

PubMed

Müller, Matthias J; Müller, Kay-Maria; Fellgiebel, Andreas

2006-05-01

To compare the psychometric properties of the Calgary Depression Rating Scale (CDRS) and the Hamilton Depression Rating Scale (HDRS) for severity assessment of depression in acute schizophrenia. During clinical routine treatment, we investigated 119 inpatients with acute schizophrenia, using the CDRS, the HDRS, and a global 4-point Depression Severity Scale (DEP-SEV). We compared CDRS and HDRS sum scores regarding their diagnostic accuracy, with global severity of depression as the criterion. We estimated sensitivity and specificity on the basis of receiver operating characteristic curves. According to global clinical ratings (DEP-SEV), 31% of patients had no depression, 19% had mild, 31% had moderate, and 19% had severe depression. Sensitivity was significantly higher (P < 0.05) for the CDRS than for the HDRS to assess mild (0.94 vs 0.76, cut-off 3 vs 10 points) or severe depression (1.00 vs 0.78, cut-off 11 vs 22 points); specificity was comparably high (> or = 0.88) for both scales. Despite the fact that both scales were effective in separating mild, moderate, and severe depression, significant advantages emerged for the CDRS to detect mild or severe depression in schizophrenia.

A Comparative Study of Anomaly Detection Techniques for Smart City Wireless Sensor Networks.

PubMed

Garcia-Font, Victor; Garrigues, Carles; Rifà-Pous, Helena

2016-06-13

In many countries around the world, smart cities are becoming a reality. These cities contribute to improving citizens' quality of life by providing services that are normally based on data extracted from wireless sensor networks (WSN) and other elements of the Internet of Things. Additionally, public administration uses these smart city data to increase its efficiency, to reduce costs and to provide additional services. However, the information received at smart city data centers is not always accurate, because WSNs are sometimes prone to error and are exposed to physical and computer attacks. In this article, we use real data from the smart city of Barcelona to simulate WSNs and implement typical attacks. Then, we compare frequently used anomaly detection techniques to disclose these attacks. We evaluate the algorithms under different requirements on the available network status information. As a result of this study, we conclude that one-class Support Vector Machines is the most appropriate technique. We achieve a true positive rate at least 56% higher than the rates achieved with the other compared techniques in a scenario with a maximum false positive rate of 5% and a 26% higher in a scenario with a false positive rate of 15%.

A Comparative Study of Anomaly Detection Techniques for Smart City Wireless Sensor Networks

PubMed Central

Garcia-Font, Victor; Garrigues, Carles; Rifà-Pous, Helena

2016-01-01

In many countries around the world, smart cities are becoming a reality. These cities contribute to improving citizens’ quality of life by providing services that are normally based on data extracted from wireless sensor networks (WSN) and other elements of the Internet of Things. Additionally, public administration uses these smart city data to increase its efficiency, to reduce costs and to provide additional services. However, the information received at smart city data centers is not always accurate, because WSNs are sometimes prone to error and are exposed to physical and computer attacks. In this article, we use real data from the smart city of Barcelona to simulate WSNs and implement typical attacks. Then, we compare frequently used anomaly detection techniques to disclose these attacks. We evaluate the algorithms under different requirements on the available network status information. As a result of this study, we conclude that one-class Support Vector Machines is the most appropriate technique. We achieve a true positive rate at least 56% higher than the rates achieved with the other compared techniques in a scenario with a maximum false positive rate of 5% and a 26% higher in a scenario with a false positive rate of 15%. PMID:27304957

CWA stand-off detection, a new figure-of-merit: the field surface scanning rate

NASA Astrophysics Data System (ADS)

Bernascolle, Philippe F.

2013-05-01

All the manufacturers of stand-off CWA detectors communicate on the "same" characteristics. And one can find these parameters in the comparison table published between all the different products [1]. These characteristics are for example the maximum detection range, the number of different detectable compounds, the weight, the price, etc… All these parameters are good to compare products between them, but they omit one very important point: the reaction time in case of an unexpected incoming chemical threat, in the case of the surveillance application. To answer this important question, we imagine a new parameter: the Field Surface Scanning Rate (FSSR). This value is a classical parameter in astronomical survey, use by astronomers to compare the performance of different telescopes, they compute the quantity of sky (in sky square degrees) analyzed per unit of time by the system. In this paper we will compare this new figure-of-merit, the FSSR, of some commercially off the shelf stand-off detector. The comparison between classical FTIR system and gas imaging system in term of FSSR will be presented.

Sensor Anomaly Detection in Wireless Sensor Networks for Healthcare

PubMed Central

Haque, Shah Ahsanul; Rahman, Mustafizur; Aziz, Syed Mahfuzul

2015-01-01

Wireless Sensor Networks (WSN) are vulnerable to various sensor faults and faulty measurements. This vulnerability hinders efficient and timely response in various WSN applications, such as healthcare. For example, faulty measurements can create false alarms which may require unnecessary intervention from healthcare personnel. Therefore, an approach to differentiate between real medical conditions and false alarms will improve remote patient monitoring systems and quality of healthcare service afforded by WSN. In this paper, a novel approach is proposed to detect sensor anomaly by analyzing collected physiological data from medical sensors. The objective of this method is to effectively distinguish false alarms from true alarms. It predicts a sensor value from historic values and compares it with the actual sensed value for a particular instance. The difference is compared against a threshold value, which is dynamically adjusted, to ascertain whether the sensor value is anomalous. The proposed approach has been applied to real healthcare datasets and compared with existing approaches. Experimental results demonstrate the effectiveness of the proposed system, providing high Detection Rate (DR) and low False Positive Rate (FPR). PMID:25884786

Efficacy of DSP30-IL2/TPA for detection of cytogenetic abnormalities in chronic lymphocytic leukaemia/small lymphocytic lymphoma.

PubMed

Holmes, P J; Peiper, S C; Uppal, G K; Gong, J Z; Wang, Z-X; Bajaj, R

2016-10-01

Chronic lymphocytic leukaemia (CLL) is the most prevalent leukaemia in the Western Hemisphere. Cytogenetic abnormalities in CLL are used for diagnosis, prognosis and treatment. However, detecting these is difficult because mature B cells do not readily divide in culture. Here, we present data on two mitogen cocktails: CpG-oligonucleotide DSP30/Interleukin-2 (IL-2) and DSP30/IL-2 in combination with 12-O-tetradecanoylphorbol-13-acetate (TPA). We analysed 165 cases of CLL with FISH and cytogenetics from January 2011 to June 2013. In 2011, three cultures were set-up: unstimulated, DSP30/IL-2-stimulated and TPA-stimulated. In 2012-2013, two cultures were set-up: unstimulated and stimulated with TPA/DSP30/IL-2. In 2011, FISH had a detection rate of 91% and cytogenetics using DSP30/IL2 had a detection rate of 91% (n = 22). In 2012-2013, FISH had a detection rate of 79% and cytogenetics using TPA/DSP30/IL-2 had a detection rate of 98% (n = 40). The percentage of cases with normal FISH but abnormal cytogenetics increased from 9% in 2011 to 21% in 2012-2013. The TPA/DSP30/IL-2 cultures in 2012-2013 detected more novel abnormalities (n = 5) as compared to DSP30/IL-2 alone (n = 3). TPA/DSP30/IL2 was as good as or better than DSP30/IL2 alone. TPA/DSP30/IL-2 offers a high detection rate for CLL abnormalities with a single stimulated culture and may increase detection of clinically significant abnormalities. © 2016 John Wiley & Sons Ltd.

Detection and genotyping of human papilloma virus in cervical cancer specimens from Saudi patients.

PubMed

Al-Badawi, Ismail A; Al-Suwaine, Abdulrahman; Al-Aker, Murad; Asaad, Lina; Alaidan, Alwaleed; Tulbah, Asma; Fe Bohol, Marie; Munkarah, Adnan R

2011-07-01

To determine the rates and types of human papilloma virus (HPV) infection in cervical cancer specimens from Saudi patients. One hundred specimens were randomly selected and retrieved from the achieved samples stored in the pathology department accessioned under the diagnosis of cervical cancer and carcinoma in situ between the years 1997 and 2007. Human papilloma virus in the clinical samples was detected using polymerase chain reaction amplification methods. Two primer systems are commonly used: the MY09-MY11 primers and the GP5+-GP6+ that amplify a wide range of HPV genotypes. Human papilloma virus isolates were genotyped using DNA sequencing and reverse line blot hybridization assay to identify the high-risk HPV genotypes. Ninety cases fulfilled the diagnostic criteria and were analyzed. The rate of HPV genotype detection among cervical cancer samples was 95.5%. The most common HPV genotype detected by both methods was HPV-16 (63.4%), followed by HPV-18 (11.1%), HPV-45 (4.5%), HPV-33 (3.3%), and HPV-31, HPV-52, HPV-53, HPV-58, HPV-59, and HPV-66 with 2.2% prevalence rate each. Prevalence of HPV genotypes among patients with cervical cancer in Saudi Arabia is comparable to the international rates. The use of the reverse line blot hybridization assay genotyping method could be useful for classifying oncogenic HPV-positive women. It is relatively inexpensive and reliable and can be performed in routine practice or epidemiological study compared with the available standard commercial kits.

[Sensitivity and specificity of the breast screening program in the Isere region based on positive results between 1991 and 1999].

PubMed

Garnier, A; Poncet, F; Billette De Villemeur, A; Exbrayat, C; Bon, M F; Chevalier, A; Salicru, B; Tournegros, J M

2009-06-01

The screening program guidelines specify that the call back rate of women for additional imaging (positive mammogram) should not exceed 7% at initial screening, and 5% at subsequent screening. Materials and methods. Results in the Isere region (12%) have prompted a review of the correlation between the call back rate and indicators of quality (detection rate, sensitivity, specificity, positive predictive value) for the radiologists providing interpretations during that time period. Three groups of radiologists were identified: the group with call back rate of 10% achieved the best results (sensitivity: 92%, detection rate: 0.53%, specificity: 90%). The group with lowest call back rate (7.7%) showed insufficient sensitivity (58%). The last group with call back rate of 18.3%, showed no improvement in sensitivity (82%) and detection rate (0.53%), but showed reduced specificity (82%). The protocol update in 2001 does not resolve this problematic situation and national results continue to demonstrate a high percentage of positive screening mammograms. A significant increase in the number of positive screening examinations compared to recommended guidelines is not advantageous and leads to an overall decrease in the quality of the screening.

Detection of spectroscopic binaries in the Gaia-ESO Survey

NASA Astrophysics Data System (ADS)

Van der Swaelmen, M.; Merle, T.; Van Eck, S.; Jorissen, A.

2017-12-01

The Gaia-ESO survey (GES) is a ground-based spectroscopic survey, complementing the Gaia mission, in order to obtain high accuracy radial velocities and chemical abundances for 10^5 stars. Thanks to the numerous spectra collected by the GES, the detection of spectroscopic multiple system candidates (SBn, n ≥ 2) is one of the science case that can be tackled. We developed at IAA (Institut d'Astronomie et d'Astrophysique) a novative automatic method to detect multiple components from the cross-correlation function (CCF) of spectra and applied it to the CCFs provided by the GES. Since the bulk of the Milky Way field targets has been observed in both HR10 and HR21 GIRAFFE settings, we are also able to compare the efficiency of our SB detection tool depending on the wavelength range. In particular, we show that HR21 leads to a less efficient detection compared to HR10. The presence of strong and/or saturated lines (Ca II triplet, Mg I line, Paschen lines) in the wavelength domain covered by HR21 hampers the computation of CCFs, which tend to be broadened compared to their HR10 counterpart. The main drawback is that the minimal detectable radial velocity difference is ˜ \\SI{60}km/s for HR21 while it is ˜ \\SI{25}km/s for HR10. A careful design of CCF masks (especially masking Ca triplet lines) can substantially improve the detectability rate of HR21. Since HR21 spectra are quite similar to the one produced by the RVS spectrograph of the Gaia mission, analysis of RVS spectra in the context of spectroscpic binaries can take adavantage of the lessons learned from the GES to maximize the detection rate.

Memory impairment is not sufficient for choice blindness to occur.

PubMed

Sagana, Anna; Sauerland, Melanie; Merckelbach, Harald

2014-01-01

Choice blindness refers to the phenomenon that people can be easily misled about the choices they made in the recent past. The aim of this study was to explore the cognitive mechanisms underlying choice blindness. Specifically, we tested whether memory impairment may account for choice blindness. A total of N = 88 participants provided sympathy ratings on 10-point scales for 20 female faces. Subsequently, participants motivated some of their ratings. However, on three trials, they were presented with sympathy ratings that deviated from their original ratings by three full scale points. On nearly 41% of the trials, participants failed to detect (i.e., were blind) the manipulation. After a short interval, participants were informed that some trials had been manipulated and were asked to recall their original ratings. Participants adopted the manipulated outcome in only 3% of the trials. Furthermore, the extent to which the original ratings were accurately remembered was not higher for detected as compared with non-detected trials. From a theoretical point of view our findings indicate that memory impairment does not fully account for blindness phenomena.

Memory impairment is not sufficient for choice blindness to occur

PubMed Central

Sagana, Anna; Sauerland, Melanie; Merckelbach, Harald

2014-01-01

Choice blindness refers to the phenomenon that people can be easily misled about the choices they made in the recent past. The aim of this study was to explore the cognitive mechanisms underlying choice blindness. Specifically, we tested whether memory impairment may account for choice blindness. A total of N = 88 participants provided sympathy ratings on 10-point scales for 20 female faces. Subsequently, participants motivated some of their ratings. However, on three trials, they were presented with sympathy ratings that deviated from their original ratings by three full scale points. On nearly 41% of the trials, participants failed to detect (i.e., were blind) the manipulation. After a short interval, participants were informed that some trials had been manipulated and were asked to recall their original ratings. Participants adopted the manipulated outcome in only 3% of the trials. Furthermore, the extent to which the original ratings were accurately remembered was not higher for detected as compared with non-detected trials. From a theoretical point of view our findings indicate that memory impairment does not fully account for blindness phenomena. PMID:24904467

Contamination Event Detection with Multivariate Time-Series Data in Agricultural Water Monitoring †

PubMed Central

Mao, Yingchi; Qi, Hai; Ping, Ping; Li, Xiaofang

2017-01-01

Time series data of multiple water quality parameters are obtained from the water sensor networks deployed in the agricultural water supply network. The accurate and efficient detection and warning of contamination events to prevent pollution from spreading is one of the most important issues when pollution occurs. In order to comprehensively reduce the event detection deviation, a spatial–temporal-based event detection approach with multivariate time-series data for water quality monitoring (M-STED) was proposed. The M-STED approach includes three parts. The first part is that M-STED adopts a Rule K algorithm to select backbone nodes as the nodes in the CDS, and forward the sensed data of multiple water parameters. The second part is to determine the state of each backbone node with back propagation neural network models and the sequential Bayesian analysis in the current timestamp. The third part is to establish a spatial model with Bayesian networks to estimate the state of the backbones in the next timestamp and trace the “outlier” node to its neighborhoods to detect a contamination event. The experimental results indicate that the average detection rate is more than 80% with M-STED and the false detection rate is lower than 9%, respectively. The M-STED approach can improve the rate of detection by about 40% and reduce the false alarm rate by about 45%, compared with the event detection with a single water parameter algorithm, S-STED. Moreover, the proposed M-STED can exhibit better performance in terms of detection delay and scalability. PMID:29207535

Reference point detection for camera-based fingerprint image based on wavelet transformation.

PubMed

Khalil, Mohammed S

2015-04-30

Fingerprint recognition systems essentially require core-point detection prior to fingerprint matching. The core-point is used as a reference point to align the fingerprint with a template database. When processing a larger fingerprint database, it is necessary to consider the core-point during feature extraction. Numerous core-point detection methods are available and have been reported in the literature. However, these methods are generally applied to scanner-based images. Hence, this paper attempts to explore the feasibility of applying a core-point detection method to a fingerprint image obtained using a camera phone. The proposed method utilizes a discrete wavelet transform to extract the ridge information from a color image. The performance of proposed method is evaluated in terms of accuracy and consistency. These two indicators are calculated automatically by comparing the method's output with the defined core points. The proposed method is tested on two data sets, controlled and uncontrolled environment, collected from 13 different subjects. In the controlled environment, the proposed method achieved a detection rate 82.98%. In uncontrolled environment, the proposed method yield a detection rate of 78.21%. The proposed method yields promising results in a collected-image database. Moreover, the proposed method outperformed compare to existing method.

Validation of an automated seizure detection algorithm for term neonates

PubMed Central

Mathieson, Sean R.; Stevenson, Nathan J.; Low, Evonne; Marnane, William P.; Rennie, Janet M.; Temko, Andrey; Lightbody, Gordon; Boylan, Geraldine B.

2016-01-01

Objective The objective of this study was to validate the performance of a seizure detection algorithm (SDA) developed by our group, on previously unseen, prolonged, unedited EEG recordings from 70 babies from 2 centres. Methods EEGs of 70 babies (35 seizure, 35 non-seizure) were annotated for seizures by experts as the gold standard. The SDA was tested on the EEGs at a range of sensitivity settings. Annotations from the expert and SDA were compared using event and epoch based metrics. The effect of seizure duration on SDA performance was also analysed. Results Between sensitivity settings of 0.5 and 0.3, the algorithm achieved seizure detection rates of 52.6–75.0%, with false detection (FD) rates of 0.04–0.36 FD/h for event based analysis, which was deemed to be acceptable in a clinical environment. Time based comparison of expert and SDA annotations using Cohen’s Kappa Index revealed a best performing SDA threshold of 0.4 (Kappa 0.630). The SDA showed improved detection performance with longer seizures. Conclusion The SDA achieved promising performance and warrants further testing in a live clinical evaluation. Significance The SDA has the potential to improve seizure detection and provide a robust tool for comparing treatment regimens. PMID:26055336

Feature Selection and Classifier Parameters Estimation for EEG Signals Peak Detection Using Particle Swarm Optimization

PubMed Central

Adam, Asrul; Mohd Tumari, Mohd Zaidi; Mohamad, Mohd Saberi

2014-01-01

Electroencephalogram (EEG) signal peak detection is widely used in clinical applications. The peak point can be detected using several approaches, including time, frequency, time-frequency, and nonlinear domains depending on various peak features from several models. However, there is no study that provides the importance of every peak feature in contributing to a good and generalized model. In this study, feature selection and classifier parameters estimation based on particle swarm optimization (PSO) are proposed as a framework for peak detection on EEG signals in time domain analysis. Two versions of PSO are used in the study: (1) standard PSO and (2) random asynchronous particle swarm optimization (RA-PSO). The proposed framework tries to find the best combination of all the available features that offers good peak detection and a high classification rate from the results in the conducted experiments. The evaluation results indicate that the accuracy of the peak detection can be improved up to 99.90% and 98.59% for training and testing, respectively, as compared to the framework without feature selection adaptation. Additionally, the proposed framework based on RA-PSO offers a better and reliable classification rate as compared to standard PSO as it produces low variance model. PMID:25243236

ERASE-Seq: Leveraging replicate measurements to enhance ultralow frequency variant detection in NGS data

PubMed Central

Kamps-Hughes, Nick; McUsic, Andrew; Kurihara, Laurie; Harkins, Timothy T.; Pal, Prithwish; Ray, Claire

2018-01-01

The accurate detection of ultralow allele frequency variants in DNA samples is of interest in both research and medical settings, particularly in liquid biopsies where cancer mutational status is monitored from circulating DNA. Next-generation sequencing (NGS) technologies employing molecular barcoding have shown promise but significant sensitivity and specificity improvements are still needed to detect mutations in a majority of patients before the metastatic stage. To address this we present analytical validation data for ERASE-Seq (Elimination of Recurrent Artifacts and Stochastic Errors), a method for accurate and sensitive detection of ultralow frequency DNA variants in NGS data. ERASE-Seq differs from previous methods by creating a robust statistical framework to utilize technical replicates in conjunction with background error modeling, providing a 10 to 100-fold reduction in false positive rates compared to published molecular barcoding methods. ERASE-Seq was tested using spiked human DNA mixtures with clinically realistic DNA input quantities to detect SNVs and indels between 0.05% and 1% allele frequency, the range commonly found in liquid biopsy samples. Variants were detected with greater than 90% sensitivity and a false positive rate below 0.1 calls per 10,000 possible variants. The approach represents a significant performance improvement compared to molecular barcoding methods and does not require changing molecular reagents. PMID:29630678

[The clinical value of sentinel lymph node detection in laryngeal and hypopharyngeal carcinoma patients with clinically negative neck by methylene blue method and radiolabeled tracer method].

PubMed

Zhao, Xin; Xiao, Dajiang; Ni, Jianming; Zhu, Guochen; Yuan, Yuan; Xu, Ting; Zhang, Yongsheng

2014-11-01

To investigate the clinical value of sentinel lymph node (SLN) detection in laryngeal and hypopharyngeal carcinoma patients with clinically negative neck (cN0) by methylene blue method, radiolabeled tracer method and combination of these two methods. Thirty-three patients with cN0 laryngeal carcinoma and six patients with cN0 hypopharyngeal carcinoma underwent SLN detection using both of methylene blue and radiolabeled tracer method. All these patients were accepted received the injection of radioactive isotope 99 Tc(m)-sulfur colloid (SC) and methylene blue into the carcinoma before surgery, then all these patients underwent intraopertive lymphatic mapping with a handheld gamma-detecting probe and blue-dyed SLN. After the mapping of SLN, selected neck dissections and tumor resections were peformed. The results of SLN detection by radiolabeled tracer, dye and combination of both methods were compared. The detection rate of SLN by radiolabeled tracer, methylene blue and combined method were 89.7%, 79.5%, 92.3% respectively. The number of detected SLN was significantly different between radiolabeled tracer method and combined method, and also between methylene blue method and combined method. The detection rate of methylene blue and radiolabeled tracer method were significantly different from combined method (P < 0.05). Nine patients were found to have lymph node metastasis by final pathological examination. The accuracy and negative rate of SLN detection of the combined method were 97.2% and 11.1%. The combined method using radiolabeled tracer and methylene blue can improve the detection rate and accuracy of sentinel lymph node detection. Furthermore, sentinel lymph node detection can accurately represent the cervical lymph node status in cN0 laryngeal and hypopharyngeal carcinoma.

CNV-TV: a robust method to discover copy number variation from short sequencing reads.

PubMed

Duan, Junbo; Zhang, Ji-Gang; Deng, Hong-Wen; Wang, Yu-Ping

2013-05-02

Copy number variation (CNV) is an important structural variation (SV) in human genome. Various studies have shown that CNVs are associated with complex diseases. Traditional CNV detection methods such as fluorescence in situ hybridization (FISH) and array comparative genomic hybridization (aCGH) suffer from low resolution. The next generation sequencing (NGS) technique promises a higher resolution detection of CNVs and several methods were recently proposed for realizing such a promise. However, the performances of these methods are not robust under some conditions, e.g., some of them may fail to detect CNVs of short sizes. There has been a strong demand for reliable detection of CNVs from high resolution NGS data. A novel and robust method to detect CNV from short sequencing reads is proposed in this study. The detection of CNV is modeled as a change-point detection from the read depth (RD) signal derived from the NGS, which is fitted with a total variation (TV) penalized least squares model. The performance (e.g., sensitivity and specificity) of the proposed approach are evaluated by comparison with several recently published methods on both simulated and real data from the 1000 Genomes Project. The experimental results showed that both the true positive rate and false positive rate of the proposed detection method do not change significantly for CNVs with different copy numbers and lengthes, when compared with several existing methods. Therefore, our proposed approach results in a more reliable detection of CNVs than the existing methods.

A Dual-Process Account of Auditory Change Detection

ERIC Educational Resources Information Center

McAnally, Ken I.; Martin, Russell L.; Eramudugolla, Ranmalee; Stuart, Geoffrey W.; Irvine, Dexter R. F.; Mattingley, Jason B.

2010-01-01

Listeners can be "deaf" to a substantial change in a scene comprising multiple auditory objects unless their attention has been directed to the changed object. It is unclear whether auditory change detection relies on identification of the objects in pre- and post-change scenes. We compared the rates at which listeners correctly identify changed…

Filling the gap between lab and clinical impact: An open randomized diagnostic trial comparing urinary ethylglucuronide and ethanol in alcohol dependent outpatients.

PubMed

Barrio, Pablo; Teixidor, Lídia; Ortega, Lluisa; Lligoña, Anna; Rico, Nayra; Bedini, José Luis; Vieta, Eduard; Gual, Antoni

2018-02-01

Efforts aimed at reducing alcohol-related harm include early detection of risky drinkers as well as detection of early relapse in patients with alcohol dependence. Ethyl glucuronide (EtG) has been proven to be a reliable biomarker for the detection of recent drinking; however, no randomized, diagnostic trial to date has tested its impact on drinking outcomes. The aim of this study was to assess, in a randomized design, the implications of EtG screening on alcohol outcomes, compared to screening with a low sensitivity biomarker such as ethanol. Alcohol dependent outpatients were randomized to either 24 weeks of continuous screening with EtG or ethanol. Patients were aware of screening methods and results. After 24 weeks, all participants were screened with EtG. Self-reports were also gathered. A logistic regression compared the rate of EtG positive results at study end between groups. Generalized estimating equations evaluated the descending monthly rate of EtG positive patients in the EtG group. A total of 162 patients were randomized. During the study period, the ethanol group showed less patients with positive screens (19/64 (29.7%) vs 58/98 (59%)). After 24 weeks, the EtG group showed a greater number of patients having a negative screening test compared to ethanol subjects when they were all screened with EtG (5/62 (8.1%) vs 13/39 (33.3%)). A significant decrease in the rate of EtG positive patients was found for the first three months of the study. Routine screening with EtG seems to reduce drinking and improve abstinence rates in alcohol dependent outpatients. Copyright © 2017 Elsevier B.V. All rights reserved.

Drop-off Detection with the Long Cane: Effects of Different Cane Techniques on Performance

PubMed Central

Kim, Dae Shik; Emerson, Robert Wall; Curtis, Amy

2010-01-01

This study compared the drop-off detection performance with the two-point touch and constant contact cane techniques using a repeated-measures design with a convenience sample of 15 cane users with visual impairments. The constant contact technique was superior to the two-point touch technique in the drop-off detection rate and the 50% detection threshold. The findings may help an orientation and mobility instructor select an appropriate technique for a particular client or training situation. PMID:21209791

[Usefulness of ¹⁸F-fluoro-2-deoxyglucose positron emission tomography in evaluation of gastric cancer stage].

PubMed

Yoon, Na Ri; Park, Jae Myung; Jung, Hee Sun; Cho, Yu Kyung; Lee, In Seok; Choi, Myung Gyu; Chung, In Sik; Song, Kyo Young; Park, Cho Hyun

2012-05-01

The usefulness of ¹⁸F-fluoro-2-deoxyglucose (FDG)-PET in detecting primary cancer, lymph node metastasis, and distant metastasis were studied in the gastric cancer patients. The subjects were 392 gastric cancer patients who received FDG-PET and an abdominal CT test prior to surgery. The results of FDG-PET and CT were compared with the surgical and pathologic results. The primary site detection rate of FDG-PET was 74.4%, 50.3% in early gastric cancer and 92.0% in advanced gastric cancer. Detection rate was higher when tumors were larger than 3.5 cm, had deeper depth of invasion, and at a later stage (p<0.05, respectively). In multivariate analysis, tumor size, spread of tumor cells beyond the muscle layer (≥T2), and lymph node metastasis were statistically significant factors in primary site detection rate. The sensitivity, specificity, and positive predictive value of FDG-PET to lymph node metastasis were 59.6%, 88.8%, and 81.1% respectively, sensitivity being lower compared to CT while specificity and positive predictive value were higher. Sensitivity, specificity, and positive predictive value to distant metastasis were, respectively, 66.7%, 99.2%, and 88.0%, similar to CT. In 21 of the 392 patients (5.4%), synchronous double primary cancers were detected. In gastric cancer, usefullness of FDG-PET is limited to the advanced stage. Diagnostic value of this test was not superior to CT. However, FDG-PET may be useful in detecting synchronous double primary cancers.

Phylogeny and species traits predict bird detectability

USGS Publications Warehouse

Solymos, Peter; Matsuoka, Steven M.; Stralberg, Diana; Barker, Nicole K. S.; Bayne, Erin M.

2018-01-01

Avian acoustic communication has resulted from evolutionary pressures and ecological constraints. We therefore expect that auditory detectability in birds might be predictable by species traits and phylogenetic relatedness. We evaluated the relationship between phylogeny, species traits, and field‐based estimates of the two processes that determine species detectability (singing rate and detection distance) for 141 bird species breeding in boreal North America. We used phylogenetic mixed models and cross‐validation to compare the relative merits of using trait data only, phylogeny only, or the combination of both to predict detectability. We found a strong phylogenetic signal in both singing rates and detection distances; however the strength of phylogenetic effects was less than expected under Brownian motion evolution. The evolution of behavioural traits that determine singing rates was found to be more labile, leaving more room for species to evolve independently, whereas detection distance was mostly determined by anatomy (i.e. body size) and thus the laws of physics. Our findings can help in disentangling how complex ecological and evolutionary mechanisms have shaped different aspects of detectability in boreal birds. Such information can greatly inform single‐ and multi‐species models but more work is required to better understand how to best correct possible biases in phylogenetic diversity and other community metrics.

Evaluating a switch from meconium to umbilical cord tissue for newborn drug testing: A retrospective study at an academic medical center.

PubMed

Palmer, Kendra L; Wood, Kelly E; Krasowski, Matthew D

2017-04-01

The objective of this study was to compare detection rates of newborn drug exposure at an academic medical center transitioning from meconium to umbilical cord tissue toxicology testing. We performed an Institutional Review Board-approved retrospective chart review on all newborns (n=2072) for whom newborn drug testing was ordered at our academic medical center between June 2012 and August 2015 (in August 2013, umbilical cord tissue became the preferred specimen). Meconium toxicology testing was positive for at least one compound in 221 cases (21.3% of 1037 total specimens), with non-medical drug use identified in 85 cases (8.2%). Umbilical cord tissue toxicology testing was positive for at least one compound in 302 cases (29.2%), with non-medical drug use identified in 107 cases (10.3%). Of the cases involving non-medical drug use, the most common compounds detected were tetrahydrocannabinol and amphetamines. Non-medical drug use did not differ significantly between meconium and umbilical cord tissue, either as a total or for classes of drugs such as amphetamines, cannabinoids, and opiates. Maternal non-medical use of tramadol (not tested for in meconium) was identified in 5 cases (0.4%). There were significant differences in rate of detection of iatrogenic medications. Specifically, morphine, lorazepam, phenobarbital, and codeine were more commonly detected in meconium, while oxycodone was more commonly detected in umbilical cord tissue. Umbilical cord tissue toxicology testing yielded a similar detection rate compared to meconium testing. The use of umbilical cord tissue avoids detection of medications given to the neonate prior to meconium collection. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

A comparative study of self-report, urinalysis and hair analysis in the detection of methamphetamine in Yaba users.

PubMed

Junkuy, Anongphan; Aramrattana, Apinun; Sribanditmongkol, Pongruk

2014-07-01

Three diagnostic methods have dominated drug-abuse research: self-report, urinalysis and hair analysis. Previous studies have compared detection rates for various drugs, but none has focused a three-pronged concordance study on the use of methamphetamine (MA). To determine and compare the rates of MA detection in urine and hair of subjects who reported consuming MA in the form of Yaba. Self-reports of Yaba use, as well as biological specimens for chemical analyses, were collected from paid volunteers participating in a larger project studying risk-taking behavior of young adults in northern Thailand. All subjects in the present study reported using Yaba within 90 days of enrollment. Hair analysis for MA followed a validated protocol that coupled solid phase microextraction (SPME) with gas chromatography-mass spectrometry (GC-MS). Preliminary urinalysis was by means of REMEDi-HS. Positive urine was confirmed for MA by the SPME/GC-MS protocol. The MA detection rate by hair analysis (34.3%, n = 172) was significantly higher than by urinalysis (19.1%, n = 96) (p < 0.01; McNemar's test). All subjects with MA-positive urine samples reported using Yaba within 30 days of testing, while hair analysis gave positive results for self-reports up to 90 days. Urinalysis showed greater concordance with self-report than hair analysis if testing occurred within seven days of most recent admitted Yaba use. The reverse was true after 14 days. Agreement of laboratory findings with self-reports increased if test results for the two biological matrices were combined. There was no strong agreement between hair analysis and urinalysis for subjects reporting most recent use within 30 days of testing (kappa = 0.131; 95% CI = 0.022-0.240). For the Yaba users in the present study, urinalysis for MA significantly detected more positives than hair analysis if the most recent use reportedly occurred within seven days of testing. Hair analysis yielded better results after an interval of 14 days, with its window of detection extending up to three months. There were no urine positive samples for reported use after 30 days. Combining urinalysis and hair analysis increased the probability of detecting recent MA use. Both urinalysis and hair analysis significantly under-detected MA in the biological samples collected. The combined detection rate was 44.4%. This discrepancy might have resulted from over-reporting of Yaba use due to social/psychological factors and/or insufficient MA consumption causing test results to fall below cutoff levels.

A Comparative Survey of Methods for Remote Heart Rate Detection From Frontal Face Videos

PubMed Central

Wang, Chen; Pun, Thierry; Chanel, Guillaume

2018-01-01

Remotely measuring physiological activity can provide substantial benefits for both the medical and the affective computing applications. Recent research has proposed different methodologies for the unobtrusive detection of heart rate (HR) using human face recordings. These methods are based on subtle color changes or motions of the face due to cardiovascular activities, which are invisible to human eyes but can be captured by digital cameras. Several approaches have been proposed such as signal processing and machine learning. However, these methods are compared with different datasets, and there is consequently no consensus on method performance. In this article, we describe and evaluate several methods defined in literature, from 2008 until present day, for the remote detection of HR using human face recordings. The general HR processing pipeline is divided into three stages: face video processing, face blood volume pulse (BVP) signal extraction, and HR computation. Approaches presented in the paper are classified and grouped according to each stage. At each stage, algorithms are analyzed and compared based on their performance using the public database MAHNOB-HCI. Results found in this article are limited on MAHNOB-HCI dataset. Results show that extracted face skin area contains more BVP information. Blind source separation and peak detection methods are more robust with head motions for estimating HR. PMID:29765940

Diagnostic performance of power doppler and ultrasound contrast agents in early imaging-based diagnosis of organ-confined prostate cancer: Is it possible to spare cores with contrast-guided biopsy?

PubMed

Delgado Oliva, F; Arlandis Guzman, S; Bonillo García, M; Broseta Rico, E; Boronat Tormo, F

2016-10-01

To evaluate the diagnostic performance of gray scale transrectal ultrasound-B-mode US (BMUS), power Doppler (PDUS), and sonographic contrast (CEUS) in early imaging-based diagnosis of localized prostate cancer (PCa) and to compare the diagnostic profitability of randomized biopsy (RB), US-targeted prostate biopsy by means of PDUS and CEUS. A single-center, prospective, transversal, epidemiological study was conducted from January 2010 to January 2014. We consecutively included patients who an imaging study of the prostate with BMUS, PDUS, and CEUS was performed, followed by prostate biopsy due to clinical suspicion of prostate cancer (PSA 4-20ng/mL and/or rectal exam suggestive of malignancy). The diagnostic performance of BMUS, PDUS, and CEUS was determined by calculating the Sensitivity (S), Specificity (Sp), Predictive values (PV), and diagnostic odds ratio (OR) of the diagnosis tests and, for these variables, in the population general and based on their clinical stage according to rectal exam (cT1 and cT2). PCa detection rates determined by means of a randomized 10-core biopsy scheme were compared with detection rates of CEUS-targeted (SonoVue) 2-core biopsies. Of the initial 984 patients, US contrast SonoVue was administered to 179 (18.2%). The PCa detection rate by organ of BMUS/PDUS in the global population was 38% versus 43% in the subpopulation with CEUS. The mean age of the patients was 64.3±7.01years (95% CI, 63.75-64.70); mean total PSA was 8.9±3.61ng/mL (95% CI, 8.67-9.13) and the mean prostate volume was 56.2±29cc (95% CI, 54.2-58.1). The detection rate by organ of targeted biopsy with BMUS, PDUS, and CEUS were as follows: Global population (10.6, 8.2, 24.5%), stage cT1 (5.6, 4.2, 16.4%), and stage cT2 (32.4, 22.3, 43.5%). Comparing the detection rates of the CEUS-targeted biopsy and randomized biopsy, the following results were obtained: Global population (24.5% vs. 41.8%), stage cT1 (16% vs. 35%), and stage cT2 (43.5% vs. 66.6%), with a p value<0.05. Following the "core-by-core" analysis, the detection rates by core of CEUS-targeted biopsy versus randomized biopsy were: Global population (16% vs. 13%), stage cT1 (30.3% vs. 28%), and stage cT2 (48% vs. 37%), with a p value>0.05. The NNT for CEUS-targeted biopsy was 83.3. The low sensitivity, specificity, positive predictive and negative predictive values of gray scale-B-mode, PDUS and CEUS represent scant diagnostic performance of these variables in prostate cancer detection. Prostate cancer detection rates yielded by randomized biopsy were superior than the detection rate of targeted biopsy using B-mode, PDUS and CEUS; as a result, randomized biopsy versus CEUS-targeted biopsies cannot be excluded from biopsy strategy plans for the diagnosis of prostate cancer. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Use of electric field sensors for recording respiration, heart rate, and stereotyped motor behaviors in the rodent home cage.

PubMed

Noble, Donald J; MacDowell, Camden J; McKinnon, Michael L; Neblett, Tamra I; Goolsby, William N; Hochman, Shawn

2017-02-01

Numerous environmental and genetic factors can contribute significantly to behavioral and cardiorespiratory variability observed experimentally. Affordable technologies that allow for noninvasive home cage capture of physio-behavioral variables should enhance understanding of inter-animal variability including after experimental interventions. We assessed whether EPIC electric field sensors (Plessey Semiconductors) embedded within or attached externally to a rodent's home cage could accurately record respiration, heart rate, and motor behaviors. Current systems for quantification of behavioral variables require expensive specialty equipment, while measures of respiratory and heart rate are often provided by surgically implanted or chronically affixed devices. Sensors accurately encoded imposed sinusoidal changes in electric field tested at frequencies ranging from 0.5-100Hz. Mini-metronome arm movements were easily detected, but response magnitude was highly distance dependent. Sensors accurately reported respiration during whole-body plethysmography. In anesthetized rodents, PVC tube-embedded sensors provided accurate mechanical detection of both respiratory and heart rate. Comparable success was seen in naturally behaving animals at rest or sleeping when sensors were attached externally. Video-verified motor behaviors (sniffing, grooming, chewing, and rearing) were detectable and largely separable by their characteristic voltage fluctuations. Larger movement-related events had comparably larger voltage dynamics that easily allowed for a broad approximation of overall motor activity. Spectrograms were used to quickly depict characteristic frequencies in long-lasting recordings, while filtering and thresholding software allowed for detection and quantification of movement-related physio-behavioral events. EPIC electric field sensors provide a means for affordable non-contact home cage detection of physio-behavioral variables. Copyright © 2016 Elsevier B.V. All rights reserved.

Pharmacovigilance data mining with methods based on false discovery rates: a comparative simulation study.

PubMed

Ahmed, I; Thiessard, F; Miremont-Salamé, G; Bégaud, B; Tubert-Bitter, P

2010-10-01

The early detection of adverse reactions caused by drugs that are already on the market is the prime concern of pharmacovigilance efforts; the methods in use for postmarketing surveillance are aimed at detecting signals pointing to potential safety concerns, on the basis of reports from health-care providers and from information available in various databases. Signal detection methods based on the estimation of false discovery rate (FDR) have recently been proposed. They address the limitation of arbitrary detection thresholds of the automatic methods in current use, including those last updated by the US Food and Drug Administration and the World Health Organization's Uppsala Monitoring Centre. We used two simulation procedures to compare the false-positive performances for three current methods: the reporting odds ratio (ROR), the information component (IC), the gamma Poisson shrinkage (GPS), and also for two FDR-based methods derived from the GPS model and Fisher's test. Large differences in FDR rates were associated with the signal-detection methods currently in use. These differences ranged from 0.01 to 12% in an analysis that was restricted to signals with at least three reports. The numbers of signals generated were also highly variable. Among fixed-size lists of signals, the FDR was lowered when the FDR-based approaches were used. Overall, the outcomes in both simulation studies suggest that improvement in effectiveness can be expected from use of the FDR-based GPS method.

Comparison of digital tomosynthesis and chest radiography for the detection of pulmonary nodules: systematic review and meta-analysis.

PubMed

Kim, Jun H; Lee, Kyung H; Kim, Kyoung-Tae; Kim, Hyun J; Ahn, Hyeong S; Kim, Yeo J; Lee, Ha Y; Jeon, Yong S

2016-12-01

To compare the diagnostic accuracy of digital tomosynthesis (DTS) with that of chest radiography for the detection of pulmonary nodules by meta-analysis. A systematic literature search was performed to identify relevant original studies from 1 January 1 1976 to 31 August 31 2016. The quality of included studies was assessed by quality assessment of diagnostic accuracy studies-2. Per-patient data were used to calculate the sensitivity and specificity and per-lesion data were used to calculate the detection rate. Summary receiver-operating characteristic curves were drawn for pulmonary nodule detection. 16 studies met the inclusion criteria. 1017 patients on a per-patient basis and 2159 lesions on a per-lesion basis from 16 eligible studies were evaluated. The pooled patient-based sensitivity of DTS was 0.85 [95% confidence interval (CI) 0.83-0.88] and the specificity was 0.95 (0.93-0.96). The pooled sensitivity and specificity of chest radiography were 0.47 (0.44-0.51) and 0.37 (0.34-0.40), respectively. The per-lesion detection rate was 2.90 (95% CI 2.63-3.19). DTS has higher diagnostic accuracy than chest radiography for detection of pulmonary nodules. Chest radiography has low sensitivity but similar specificity, comparable with that of DTS. Advances in knowledge: DTS has higher diagnostic accuracy than chest radiography for the detection of pulmonary nodules.

The impact of training in problem-based interviewing on the detection and management of psychological problems presenting in primary care.

PubMed Central

Scott, J; Jennings, T; Standart, S; Ward, R; Goldberg, D

1999-01-01

BACKGROUND: The vast majority of mental health problems present to primary care teams. However, rates of under-diagnosis remain worryingly high. This study explores a GP-centred approach to these issues. AIM: To examine the impact of training in problem-based interviewing (BPI) on the detection and management of psychological problems in primary care. METHOD: The detection and management of psychological problems by 10 general practitioners (GPs) who had received PBI training 12 months earlier was compared with that of 10 control GPs matched for age, sex, clinical experience, and practice setting; and had originally applied for, but had not been able to attend, BPI training. Consecutive attendees at one randomly selected surgery undertaken by each GP were invited to participate in the study. Two hundred and eighty patients living in Newcastle upon Tyne met inclusion criteria and gave informed consent. The presence or absence of psychological problems was assessed using patient self-ratings on the 28-item version of the General Health Questionnaire (GHQ) and blind independent observer ratings of the brief Present State Examination (PSE). Patient satisfaction with interviews was rated using the Medical Interview Satisfaction Scale (MISS). After each consultation, the GPs (blind to subjective and observer ratings) recorded their assessment and management of the patients' problems on a Practice Activity Card (PAC). RESULTS: In comparison with control GPs, index GPs demonstrated significantly greater sensitivity in the detection of psychological problems in the GHQ-PAC ratings. The absolute decrease in misdiagnosis of GHQ cases was 9% and of PSE cases was 15%. Patients meeting GHQ criteria for caseness were more likely to be prescribed psychotropic medication by an index GP than compared with a control GP. Length of interview did not differ between the groups and mean scores on the MISS suggested that patients attending PBI-trained GPs, compared with control GPs, were as satisfied or slightly more satisfied with their consultation. CONCLUSION: In comparison with control GPs, PBI-trained GPs were better at recognizing and managing psychological disorders. The potential benefits of BPI training are discussed in light of other attempts to improve mental health skills in primary care. PMID:10562742

Adenoma Detection Rates for Screening Colonoscopies in Smokers and Obese Adults: Data From the New Hampshire Colonoscopy Registry.

PubMed

Anderson, Joseph C; Weiss, Julia E; Robinson, Christina M; Butterly, Lynn F

To examine screening adenoma detection rates (ADR) and serrated detection rates (SDR) among smokers and obese adults in the New Hampshire Colonoscopy Registry. ADR, a quality measure for screening colonoscopies, is associated with protection from interval colorectal cancer. Currently, only sex-specific ADR benchmarks are reported. However, obesity and smoking ≥20 pack-years are strong predictors for colorectal neoplasia, as highlighted by the 2009 American College of Gastroenterology CRC Screening Guidelines. Data comparing ADR in smokers and obese adults to those without these risks are limited. We calculated ADR, SDR, and 95% confidence intervals for screening colonoscopies in participants ≥50 years. Sex-specific and sex-age-specific rates were compared by smoking exposure (never vs. <20 vs. ≥20 pack-years) and body mass index (<30 vs. ≥30). A total of 21,539 screening colonoscopies were performed by 77 endoscopists at 20 facilities (April 2009 to September 2013). The difference in ADR between nonsmokers and smokers with ≥20 pack-years was 8.8% (P<0.0001) and between obesity groups 5.0% (P<0.0001). Significant sex-specific and sex-age-specific increases in ADR and SDR were found among smokers and obese participants. ADR and SDR for smokers and obese adults were significantly higher than their counterparts without those risks. Endoscopists should consider the prevalence of these risks within their screening population when comparing their rates to established benchmarks. Calculating sex-specific or sex-age-specific ADR and SDR based on smoking and obesity may provide optimal protection for populations with a particularly high prevalence of smokers and obese adults.

AdaBoost-based algorithm for network intrusion detection.

PubMed

Hu, Weiming; Hu, Wei; Maybank, Steve

2008-04-01

Network intrusion detection aims at distinguishing the attacks on the Internet from normal use of the Internet. It is an indispensable part of the information security system. Due to the variety of network behaviors and the rapid development of attack fashions, it is necessary to develop fast machine-learning-based intrusion detection algorithms with high detection rates and low false-alarm rates. In this correspondence, we propose an intrusion detection algorithm based on the AdaBoost algorithm. In the algorithm, decision stumps are used as weak classifiers. The decision rules are provided for both categorical and continuous features. By combining the weak classifiers for continuous features and the weak classifiers for categorical features into a strong classifier, the relations between these two different types of features are handled naturally, without any forced conversions between continuous and categorical features. Adaptable initial weights and a simple strategy for avoiding overfitting are adopted to improve the performance of the algorithm. Experimental results show that our algorithm has low computational complexity and error rates, as compared with algorithms of higher computational complexity, as tested on the benchmark sample data.

Doppler endoscopic probe as a guide to risk stratification and definitive hemostasis of peptic ulcer bleeding.

PubMed

Jensen, Dennis M; Ohning, Gordon V; Kovacs, Thomas O G; Ghassemi, Kevin A; Jutabha, Rome; Dulai, Gareth S; Machicado, Gustavo A

2016-01-01

For more than 4 decades endoscopists have relied on ulcer stigmata for risk stratification and as a guide to hemostasis. None used arterial blood flow underneath stigmata to predict outcomes. For patients with severe peptic ulcer bleeding (PUB), we used a Doppler endoscopic probe (DEP) for (1) detection of blood flow underlying stigmata of recent hemorrhage (SRH), (2) quantitating rates of residual arterial blood flow under SRH after visually directed standard endoscopic treatment, and (3) comparing risks of rebleeding and actual 30-day rebleed rates for spurting arterial bleeding (Forrest [F] IA) and oozing bleeding (F IB). Prospective cohort study of 163 consecutive patients with severe PUB and different SRH. All blood flow detected by the DEP was arterial. Detection rates were 87.4% in major SRH-spurting arterial bleeding (F IA), non-bleeding visible vessel (F IIA), clot (F IIB)-and were significantly lower at 42.3% (P < .0001) for an intermediate group of oozing bleeding (F IB) or flat spot (F IIC). For spurting bleeding (F IA) versus oozing (F IB), baseline DEP arterial flow was 100% versus 46.7%, residual blood flow detected after endoscopic hemostasis was 35.7% versus 0%, and 30-day rebleed rates were 28.6% versus 0% (all P < .05). (1) For major SRH versus oozing or spot, the arterial blood flow detection rate by the DEP was significantly higher, indicating a higher rebleed risk. (2) Before and after endoscopic treatment, spurting (F IA) PUB had significantly higher rates of blood flow detection than oozing (F IB) PUB and a significantly higher 30-day rebleed rate. (3) The DEP is recommended as a new endoscopic guide with SRH to improve risk stratification and potentially definitive hemostasis for PUB. Published by Elsevier Inc.

Doppler Endoscopic Probe as a Guide to Risk Stratification and Definitive Hemostasis of Peptic Ulcer Bleeding

PubMed Central

Jensen, Dennis M.; Ohning, Gordon V.; Kovacs, Thomas OG; Ghassemi, Kevin A.; Jutabha, Rome; Dulai, Gareth S.; Machicado, Gustavo A.

2015-01-01

Background and Aims For more than 4 decades endoscopists have relied on ulcer stigmata for risk stratification and as a guide to hemostasis. None used arterial blood flow underneath stigmata to predict outcomes. For patients with severe peptic ulcer bleeding (PUBs), we used Doppler endoscopic probe (DEP) for: 1. detection of blood flow underlying stigmata of recent hemorrhage (SRH), 2. quantitating rates of residual arterial blood flow under SRH after visually directed standard endoscopic treatment, and 3. comparing risks of rebleeding and actual 30 day rebleed rates for spurting arterial bleeding (Forrest – FIA) and oozing bleeding (FIB). Methods Prospective cohort study of 163 consecutive patients with severe PUBs and different SRH. Results All blood flow detected by DEP was arterial. Detection rates were 87.4% in major SRH - spurting arterial bleeding (FIA), non bleeding visible vessel (FIIA), clot (FIIB) - and significantly lower at 42.3% (p<0.0001) for intermediate group of oozing bleeding (FIB) or flat spot (FIIC). For spurting bleeding (FIA) vs. oozing (FIB), baseline DEP arterial flow was 100% vs. 46.7%; residual blood flow detected after endoscopic hemostasis was 35.7% vs. 0%; and 30 day rebleed rates were 28.6% vs. 0% (all p<0.05). Conclusions 1. For major SRH vs. oozing or spot, the arterial blood flow detection rates by DEP was significantly higher, indicating a higher rebleed risk. 2. Before and after endoscopic treatment, spurting FIA PUB’s had significantly higher rates of blood flow detection than oozing FIB PUB’s and a significantly higher 30 rebleed rate. 3. DEP is recommended as a new endoscopic guide with SRH to improve risk stratification and potentially definitive hemostasis for PUBs. PMID:26318834

[Lesions Detected in Six Spanish Colorectal Cancer Screening Population Based Programmes. CRIBEA Project. Spain].

PubMed

Portillo Villares, Isabel; Arana-Arri, Eunate; Idigoras Rubio, Isabel; Espinás Piñol, Josep Alfons; Pérez Riquelme, Francisco; de la Vega Prieto, Mariola; González Aledo, Alvaro; Oceja Setien, Elena; Vanaclocha Espi, Mercedes; Ibáñez Cabanell, Josefa; Salas Trejo, Dolores

2017-02-20

In this study, the results of six Colorectal Cancer Screening Population Programmes are shown (Catalonia, Valence, Murcia, Cantabria, the Basque Country and the Canary Islands collected between 2005 and 2012. These programmes use the faeces occult blood test (FOBt) biennial. Objective: To determine and compare the results of lesions detected by the programmes, participation, sex, age and test used. Retrospective cohort study based on people invited, aged between 50-74 years, in at least a complete round. Lesions considered: Advanced Adenomas (AA), Colorectal Invasive Cancer (CRC) and both of them, known as Advanced Neoplasia (AN). Logistic Regression and time trends are used. 1,995,719 of invitations registered, with an average participation-rate of 46.7%. 21,228 Advanced Neoplasias (2,813 CRC and 18,415 AA). Differences in detection rates observed between programmes (varying from 15.1‰ to 35.8‰ between participants). Participation rates were related to lesions' detection rates (OR 1.25 in 40-60% of participation). . Inmunochemical qualitative test showed an OR of 4.79 and quantitative test an OR of 7.30 over the guaiac test. Men showed an OR of 2.73 with respect to women. In 2012 the Advanced Neoplasia rate for women and men was 33.1 and 14.2 by 1,000 participants. The test used was the most important factor for detecting lesions. Time trends showed an increase in detected lesions caused by the change of the type of test in 2010.

Detection of Helicobacter pylori DNA in inflamed dental pulp specimens from Japanese children and adolescents.

PubMed

Ogaya, Yuko; Nomura, Ryota; Watanabe, Yoshiyuki; Nakano, Kazuhiko

2015-01-01

The oral cavity has been implicated as a source of Helicobacter pylori infection in childhood. Various PCR methods have been used to detect H. pylori DNA in oral specimens with various detection rates reported. Such disparity in detection rates complicates the estimation of the true infection rate of H. pylori in the oral cavity. In the present study, we constructed a novel PCR system for H. pylori detection and used it to analyse oral specimens. Firstly, the nucleotide alignments of genes commonly used for H. pylori detection were compared using the complete genome information for 48 strains registered in the GenBank database. Candidate primer sets with an estimated amplification size of approximately 300-400 bp were selected, and the specificity and sensitivity of the detection system using each primer set were evaluated. Five sets of primers targeting ureA were considered appropriate, of which a single primer set was chosen for inclusion in the PCR system. The sensitivity of the system was considered appropriate and its detection limit established as one to ten cells per reaction. The novel PCR system was used to examine H. pylori distribution in oral specimens (40 inflamed pulp tissues, 40 saliva samples) collected from Japanese children, adolescents and young adults. PCR analysis revealed that the detection rate of H. pylori in inflamed pulp was 15 %, whereas no positive reaction was found in any of the saliva specimens. Taken together, our novel PCR system was found to be reliable for detecting H. pylori. The results obtained showed that H. pylori was detected in inflamed pulp but not saliva specimens, indicating that an infected root canal may be a reservoir for H. pylori. © 2015 The Authors.

[Shock shape representation of sinus heart rate based on cloud model].

PubMed

Yin, Wenfeng; Zhao, Jie; Chen, Tiantian; Zhang, Junjian; Zhang, Chunyou; Li, Dapeng; An, Baijing

2014-04-01

The present paper is to analyze the trend of sinus heart rate RR interphase sequence after a single ventricular premature beat and to compare it with the two parameters, turbulence onset (TO) and turbulence slope (TS). Based on the acquisition of sinus rhythm concussion sample, we in this paper use a piecewise linearization method to extract its linear characteristics, following which we describe shock form with natural language through cloud model. In the process of acquisition, we use the exponential smoothing method to forecast the position where QRS wave may appear to assist QRS wave detection, and use template to judge whether current cardiac is sinus rhythm. And we choose some signals from MIT-BIH Arrhythmia Database to detect whether the algorithm is effective in Matlab. The results show that our method can correctly detect the changing trend of sinus heart rate. The proposed method can achieve real-time detection of sinus rhythm shocks, which is simple and easily implemented, so that it is effective as a supplementary method.

The effect of simulated field storage conditions on the accuracy of rapid user-friendly blood pathogen detection kits.

PubMed

Bienek, Diane R; Charlton, David G

2012-05-01

Being able to test for the presence of blood pathogens at forward locations could reduce morbidity and mortality in the field. Rapid, user-friendly blood typing kits for detecting Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), and Hepatitis B Virus (HBV) were evaluated to determine their accuracy after storage at various temperatures/humidities. Rates of positive tests of control groups, experimental groups, and industry standards were compared (Fisher's exact chi2, p < or = 0.05). Compared to the control group, 2 of 10 HIV detection devices were adversely affected by exposure to high temperature/high humidity or high temperature/low humidity. With one exception, none of the environmentally exposed HCV or HBV detection devices exhibited significant differences compared to those stored under control conditions. For HIV, HCV, and HBV devices, there were differences compared to the industry standard. Collectively, this evaluation of pathogen detection kits revealed that diagnostic performance varies among products and storage conditions, and that the tested products cannot be considered to be approved for use to screen blood, plasma, cell, or tissue donors.

Optical spectral sweep comb liquid flow rate sensor.

PubMed

Shen, Changyu; Lian, Xiaokang; Kavungal, Vishnu; Zhong, Chuan; Liu, Dejun; Semenova, Yuliya; Farrell, Gerald; Albert, Jacques; Donegan, John F

2018-02-15

In microfluidic chip applications, the flow rate plays an important role. Here we propose a simple liquid flow rate sensor by using a tilted fiber Bragg grating (TFBG) as the sensing element. As the water flows in the vicinity of the TFBG along the fiber axis direction, the TFBG's spectrum changes due to its contact with water. By comparing the time-swept spectra of the TFBG in water to that of the TFBG with water flowing over it, a spectral sweep comb was formed, and the flow rate can be detected by selecting a suitable sweeping frequency. The proposed sensor has a high Q-value of over 17,000 for the lower rate and a large detectable range from 0.0058 mm/s to 3.2 mm/s. And the calculated corresponding lower detectable flow rate of 0.03 nL/s is 3 orders magnitude better than that of the current fiber flowmeter. Meanwhile, the proposed sensor has the temperature self-compensation function for the variation of the external temperature. We believe that this simple configuration will open a research direction of the TFBG-deriving theory and configuration for lower flow rate measurements for microfluidic chip applications.

Decision-level fusion of SAR and IR sensor information for automatic target detection

NASA Astrophysics Data System (ADS)

Cho, Young-Rae; Yim, Sung-Hyuk; Cho, Hyun-Woong; Won, Jin-Ju; Song, Woo-Jin; Kim, So-Hyeon

2017-05-01

We propose a decision-level architecture that combines synthetic aperture radar (SAR) and an infrared (IR) sensor for automatic target detection. We present a new size-based feature, called target-silhouette to reduce the number of false alarms produced by the conventional target-detection algorithm. Boolean Map Visual Theory is used to combine a pair of SAR and IR images to generate the target-enhanced map. Then basic belief assignment is used to transform this map into a belief map. The detection results of sensors are combined to build the target-silhouette map. We integrate the fusion mass and the target-silhouette map on the decision level to exclude false alarms. The proposed algorithm is evaluated using a SAR and IR synthetic database generated by SE-WORKBENCH simulator, and compared with conventional algorithms. The proposed fusion scheme achieves higher detection rate and lower false alarm rate than the conventional algorithms.

Strategies and limitations for fluorescence detection of XAFS at high flux beamlines

DOE PAGES

Heald, Steve M.

2015-02-17

The issue of detecting the XAFS signal from dilute samples is discussed in detail with the aim of making best use of high flux beamlines that provide up to 10 13 photons -1. Various detection methods are compared, including filters with slits, solid state detectors, crystal analyzers and combinations of these. These comparisons rely on simulations that use experimentally determined parameters. It is found that inelastic scattering places a fundamental limit on detection, and that it is important to take proper account of the polarization dependence of the signals. The combination of a filter–slit system with a solid state detectormore » is a promising approach. With an optimized system good performance can be obtained even if the total count rate is limited to 10 7 Hz. Detection schemes with better energy resolution can help at the largest dilutions if their collection efficiency and count rate limits can be improved.« less

Strategies and limitations for fluorescence detection of XAFS at high flux beamlines

PubMed Central

Heald, Steve M.

2015-01-01

The issue of detecting the XAFS signal from dilute samples is discussed in detail with the aim of making best use of high flux beamlines that provide up to 1013 photons s−1. Various detection methods are compared, including filters with slits, solid state detectors, crystal analyzers and combinations of these. These comparisons rely on simulations that use experimentally determined parameters. It is found that inelastic scattering places a fundamental limit on detection, and that it is important to take proper account of the polarization dependence of the signals. The combination of a filter–slit system with a solid state detector is a promising approach. With an optimized system good performance can be obtained even if the total count rate is limited to 107 Hz. Detection schemes with better energy resolution can help at the largest dilutions if their collection efficiency and count rate limits can be improved. PMID:25723945

Are concurrent systematic cores needed at the time of targeted biopsy in patients with prior negative prostate biopsies?

PubMed

Albisinni, S; Aoun, F; Noel, A; El Rassy, E; Lemort, M; Paesmans, M; van Velthoven, R; Roumeguère, T; Peltier, A

2018-01-01

MRI-guided targeted biopsies are advised in patients who have undergone an initial series of negative systematic biopsies, in whom prostate cancer (PCa) suspicion remains elevated. The aim of the study was to evaluate whether, in men with prior negative prostate biopsies, systematic cores are also warranted at the time of an MRI-targeted repeat biopsy. We enrolled patients with prior negative biopsy undergoing real time MRI/TRUS fusion guided prostate biopsy at our institute between 2014 and 2016. Patients with at least one index lesion on multiparametric MRI were included. All eligible patients underwent both systematic random biopsies (12-14 cores) and targeted biopsies (2-4 cores). The study included 74 men with a median age of 65 years, PSA level of 9.27ng/mL, and prostatic volume of 45ml. The overall PCa detection rate and the clinically significant cancer detection rate were 56.7% and 39.2%, respectively. Targeted cores demonstrated similar clinically significant PCa detection rate compared to systematic cores (33.8% vs. 28.4%, P=0.38) with significantly less tissue sampling. Indeed, a combination approach was significantly superior to a targeted-only in overall PCa detection (+16.7% overall detection rate, P=0.007). Although differences in clinically significant PCa detection were statistically non-significant (P=0.13), a combination approach did allow detecting 7 extra clinically significant PCas (+13.8%). In patients with elevated PSA and prior negative biopsies, concurrent systematic sampling may be needed at the time of targeted biopsy in order to maximize PCa detection rate. Larger studies are needed to validate our findings. 4. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Localization of MEG pathologic gamma oscillations in adult epilepsy patients with focal cortical dysplasia☆

PubMed Central

Jeong, Woorim; Kim, June Sic; Chung, Chun Kee

2013-01-01

We aimed to evaluate the clinical value of gamma oscillations in MEG for intractable neocortical epilepsy patients with cortical dysplasia by comparing gamma and interictal spike events. A retrospective analysis of MEG recordings of 30 adult neocortical epilepsy patients was performed. Gamma (30–70 Hz) and interictal spike events were independently identified, their independent or concurrent presence determined, and their source localization rates compared. Of 30 patients, gamma activities were detected in 28 patients and interictal spikes in 24 patients. Gamma events alone appeared in 5 patients, interictal spikes alone in 1 patient, and no events in 1 patient. Gamma co-occurred with interictal spikes in 20.1 ± 22.1% and interictal spikes co-occurred with gamma in 15.0 ± 19.2%. Rates of event localization within the resection cavity were significantly different (p = 0.042) between gamma (63.3 ± 32.6%) and interictal spike (47.0 ± 41.3%) events. In 4 of the 5 gamma-only patients the mean localization rate was 42.5%. Compared with the interictal spike localization rate, 4 of 9 seizure-free patients had higher gamma localization rates, 4 had the same rate, and 1 had a lower rate. Individual gamma events can be detected independently from interictal spike presence. Gamma can be localized to the resection cavity at least comparably to or more frequently than that from interictal spikes. Even when interictal spikes were undetected, gamma sources were localized to the resection cavity. Gamma oscillations may be a useful indicator of epileptogenic focus. PMID:24273733

Mapping slope movements in Alpine environments using TerraSAR-X interferometric methods

NASA Astrophysics Data System (ADS)

Barboux, Chloé; Strozzi, Tazio; Delaloye, Reynald; Wegmüller, Urs; Collet, Claude

2015-11-01

Mapping slope movements in Alpine environments is an increasingly important task in the context of climate change and natural hazard management. We propose the detection, mapping and inventorying of slope movements using different interferometric methods based on TerraSAR-X satellite images. Differential SAR interferograms (DInSAR), Persistent Scatterer Interferometry (PSI), Short-Baseline Interferometry (SBAS) and a semi-automated texture image analysis are presented and compared in order to determine their contribution for the automatic detection and mapping of slope movements of various velocity rates encountered in Alpine environments. Investigations are conducted in a study region of about 6 km × 6 km located in the Western Swiss Alps using a unique large data set of 140 DInSAR scenes computed from 51 summer TerraSAR-X (TSX) acquisitions from 2008 to 2012. We found that PSI is able to precisely detect only points moving with velocities below 3.5 cm/yr in the LOS, with a root mean squared error of about 0.58 cm/yr compared to DGPS records. SBAS employed with 11 days summer interferograms increases the range of detectable movements to rates up to 35 cm/yr in the LOS with a root mean squared error of 6.36 cm/yr, but inaccurate measurements due to phase unwrapping are already possible for velocity rates larger than 20 cm/year. With the semi-automated texture image analysis the rough estimation of the velocity rates over an outlined moving zone is accurate for rates of "cm/day", "dm/month" and "cm/month", but due to the decorrelation of yearly TSX interferograms this method fails for the observation of slow movements in the "cm/yr" range.

Frequency doubling technology perimetry for detection of visual field progression in glaucoma: a pointwise linear regression analysis.

PubMed

Liu, Shu; Yu, Marco; Weinreb, Robert N; Lai, Gilda; Lam, Dennis Shun-Chiu; Leung, Christopher Kai-Shun

2014-05-02

We compared the detection of visual field progression and its rate of change between standard automated perimetry (SAP) and Matrix frequency doubling technology perimetry (FDTP) in glaucoma. We followed prospectively 217 eyes (179 glaucoma and 38 normal eyes) for SAP and FDTP testing at 4-month intervals for ≥36 months. Pointwise linear regression analysis was performed. A test location was considered progressing when the rate of change of visual sensitivity was ≤-1 dB/y for nonedge and ≤-2 dB/y for edge locations. Three criteria were used to define progression in an eye: ≥3 adjacent nonedge test locations (conservative), any three locations (moderate), and any two locations (liberal) progressed. The rate of change of visual sensitivity was calculated with linear mixed models. Of the 217 eyes, 6.1% and 3.9% progressed with the conservative criteria, 14.5% and 5.6% of eyes progressed with the moderate criteria, and 20.1% and 11.7% of eyes progressed with the liberal criteria by FDTP and SAP, respectively. Taking all test locations into consideration (total, 54 × 179 locations), FDTP detected more progressing locations (176) than SAP (103, P < 0.001). The rate of change of visual field mean deviation (MD) was significantly faster for FDTP (all with P < 0.001). No eyes showed progression in the normal group using the conservative and the moderate criteria. With a faster rate of change of visual sensitivity, FDTP detected more progressing eyes than SAP at a comparable level of specificity. Frequency doubling technology perimetry can provide a useful alternative to monitor glaucoma progression.

Early diagnosis of dengue in travelers: comparison of a novel real-time RT-PCR, NS1 antigen detection and serology.

PubMed

Huhtamo, Eili; Hasu, Essi; Uzcátegui, Nathalie Y; Erra, Elina; Nikkari, Simo; Kantele, Anu; Vapalahti, Olli; Piiparinen, Heli

2010-01-01

The increased traveling to dengue endemic regions and the numerous epidemics have led to a rise in imported dengue. The laboratory diagnosis of acute dengue requires several types of tests and often paired samples are needed for obtaining reliable results. Although several diagnostic methods are available, proper comparative data on their performance are lacking. To compare the performance of novel methods including a novel pan-DENV real-time RT-PCR and a commercially available NS1 capture-EIA in regard to IgM detection for optimizing the early diagnosis of DENV in travelers. A panel of 99 selected early phase serum samples of dengue patients was studied by real-time RT-PCR, NS1 antigen ELISA, IgM-EIA, IgG-IFA and cell culture virus isolation. The novel real-time RT-PCR was shown specific and sensitive for detection of DENV-1-4 RNA and suitable for diagnostic use. The diagnostic rate using combination of RNA and IgM detection was 99% and using NS1 and IgM detection 95.9%. The results of RNA and NS1 antigen detection disagreed in 15.5% of samples that had only RNA or NS1 antigen detected. The diagnostic rates of early samples are higher when either RNA or NS1 antigen detection is combined with IgM detection. Besides the differences in the RNA and NS1 detection assays, the observed discrepancy of results could suggest individual variation or differences in timing of these markers in patient serum. Copyright (c) 2009 Elsevier B.V. All rights reserved.

Variability in testing policies and impact on reported Clostridium difficile infection rates: results from the pilot Longitudinal European Clostridium difficile Infection Diagnosis surveillance study (LuCID).

PubMed

Davies, K; Davis, G; Barbut, F; Eckert, C; Petrosillo, N; Wilcox, M H

2016-12-01

Lack of standardised Clostridium difficile testing is a potential confounder when comparing infection rates. We used an observational, systematic, prospective large-scale sampling approach to investigate variability in C. difficile sampling to understand C. difficile infection (CDI) incidence rates. In-patient and institutional data were gathered from 60 European hospitals (across three countries). Testing methodology, testing/CDI rates and case profiles were compared between countries and institution types. The mean annual CDI rate per hospital was lowest in the UK and highest in Italy (1.5 vs. 4.7 cases/10,000 patient bed days [pbds], p < 0.001). The testing rate was highest in the UK compared with Italy and France (50.7/10,000 pbds vs. 31.5 and 30.3, respectively, p < 0.001). Only 58.4 % of diarrhoeal samples were tested for CDI across all countries. Overall, only 64 % of hospitals used recommended testing algorithms for laboratory testing. Small hospitals were significantly more likely to use standalone toxin tests (SATTs). There was an inverse correlation between hospital size and CDI testing rate. Hospitals using SATT or assays not detecting toxin reported significantly higher CDI rates than those using recommended methods, despite testing similar testing frequencies. These data are consistent with higher false-positive rates in such (non-recommended) testing scenarios. Cases in Italy and those diagnosed by SATT or methods NOT detecting toxin were significantly older. Testing occurred significantly earlier in the UK. Assessment of testing practice is paramount to the accurate interpretation and comparison of CDI rates.

Comparative performance between compressed and uncompressed airborne imagery

NASA Astrophysics Data System (ADS)

Phan, Chung; Rupp, Ronald; Agarwal, Sanjeev; Trang, Anh; Nair, Sumesh

2008-04-01

The US Army's RDECOM CERDEC Night Vision and Electronic Sensors Directorate (NVESD), Countermine Division is evaluating the compressibility of airborne multi-spectral imagery for mine and minefield detection application. Of particular interest is to assess the highest image data compression rate that can be afforded without the loss of image quality for war fighters in the loop and performance of near real time mine detection algorithm. The JPEG-2000 compression standard is used to perform data compression. Both lossless and lossy compressions are considered. A multi-spectral anomaly detector such as RX (Reed & Xiaoli), which is widely used as a core algorithm baseline in airborne mine and minefield detection on different mine types, minefields, and terrains to identify potential individual targets, is used to compare the mine detection performance. This paper presents the compression scheme and compares detection performance results between compressed and uncompressed imagery for various level of compressions. The compression efficiency is evaluated and its dependence upon different backgrounds and other factors are documented and presented using multi-spectral data.

Clinical Study of Styping Detection of Human Papillomavirus (HPV) Infection with Microarray from Paraffinembedded Specimens of Cervical Cancer and Precursor Lesions.

PubMed

Li, Hai; Wang, Xubo; Geng, Jianxiang; Zhao, Xue

2015-09-01

The prevalence and type distribution of human papillomavirus (HPV) in cervical cancer and cervical intraepithelial neoplasia (CIN) in Jiangsu, China was investigated. A total of 93 cases with cervical cancer and 176 CINII-III tissue samples were obtained from women undergoing biopsy or surgery. The 1047 exfoliated cervical cell samples were collected with cervical brush in physical examination women. HPV DNA and typing were examined by polymerase chain reaction (PCR) and gene-chip. The results showed that HPV DNA was detected in 82 cases with cervical cancer (88.17%), HPV 16 being detected in 65 (69.89%) cases, HPV 18 in 12 (12.90%) cases, HPV 33 in 10 (10.75%) cases, HPV 31 in 4 (4.30%) cases, and HPV 45 in 3 (3.23%) cases. HPV DNA was detected in 154 cases with CINII-III (87.50%), HPV 16 being detected in 92 (52.27%) cases, HPV 18 in 50 (28.41%) cases, HPV 33 in 25 (14.21%) cases, HPV 58 in 25 (14.21%) cases, and HPV 31 in 20 (11.36%) cases. About 20.43% cervical cancer and 38.64% CINII-III specimens exhibited multiple infections (p < 0.01). The total positive rate, single infection and mixed infection rate of the CINII-III and SCC group all had a significant difference (p < 0.05) when compared with the normal cells group. The total positive rate, single infection rate and mixed infection rate of CINII-III group did not show significant difference (p > 0.05) when compared with SCC group. CINII-III and SCC had all intimate relation with HPV infection. The high prevalence of HPV 16, 18, 33, 31 and 58 in Jiangsu (China) deserves more attention, as it has important implications for the successful use of HPV vaccine and choice of diagnostic methods.

A novel onset detection technique for brain-computer interfaces using sound-production related cognitive tasks in simulated-online system

NASA Astrophysics Data System (ADS)

Song, YoungJae; Sepulveda, Francisco

2017-02-01

Objective. Self-paced EEG-based BCIs (SP-BCIs) have traditionally been avoided due to two sources of uncertainty: (1) precisely when an intentional command is sent by the brain, i.e., the command onset detection problem, and (2) how different the intentional command is when compared to non-specific (or idle) states. Performance evaluation is also a problem and there are no suitable standard metrics available. In this paper we attempted to tackle these issues. Approach. Self-paced covert sound-production cognitive tasks (i.e., high pitch and siren-like sounds) were used to distinguish between intentional commands (IC) and idle states. The IC states were chosen for their ease of execution and negligible overlap with common cognitive states. Band power and a digital wavelet transform were used for feature extraction, and the Davies-Bouldin index was used for feature selection. Classification was performed using linear discriminant analysis. Main results. Performance was evaluated under offline and simulated-online conditions. For the latter, a performance score called true-false-positive (TFP) rate, ranging from 0 (poor) to 100 (perfect), was created to take into account both classification performance and onset timing errors. Averaging the results from the best performing IC task for all seven participants, an 77.7% true-positive (TP) rate was achieved in offline testing. For simulated-online analysis the best IC average TFP score was 76.67% (87.61% TP rate, 4.05% false-positive rate). Significance. Results were promising when compared to previous IC onset detection studies using motor imagery, in which best TP rates were reported as 72.0% and 79.7%, and which, crucially, did not take timing errors into account. Moreover, based on our literature review, there is no previous covert sound-production onset detection system for spBCIs. Results showed that the proposed onset detection technique and TFP performance metric have good potential for use in SP-BCIs.

Direct Detection Electron Energy-Loss Spectroscopy: A Method to Push the Limits of Resolution and Sensitivity.

PubMed

Hart, James L; Lang, Andrew C; Leff, Asher C; Longo, Paolo; Trevor, Colin; Twesten, Ray D; Taheri, Mitra L

2017-08-15

In many cases, electron counting with direct detection sensors offers improved resolution, lower noise, and higher pixel density compared to conventional, indirect detection sensors for electron microscopy applications. Direct detection technology has previously been utilized, with great success, for imaging and diffraction, but potential advantages for spectroscopy remain unexplored. Here we compare the performance of a direct detection sensor operated in counting mode and an indirect detection sensor (scintillator/fiber-optic/CCD) for electron energy-loss spectroscopy. Clear improvements in measured detective quantum efficiency and combined energy resolution/energy field-of-view are offered by counting mode direct detection, showing promise for efficient spectrum imaging, low-dose mapping of beam-sensitive specimens, trace element analysis, and time-resolved spectroscopy. Despite the limited counting rate imposed by the readout electronics, we show that both core-loss and low-loss spectral acquisition are practical. These developments will benefit biologists, chemists, physicists, and materials scientists alike.

Variation in detection of ductal carcinoma in situ (DCIS) during screening mammography A survey within the International Cancer Screening Network (ICSN)

PubMed Central

Lynge, Elsebeth; Ponti, Antonio; James, Ted; Májek, Ondřej; von Euler-Chelpin, My; Anttila, Ahti; Fitzpatrick, Patricia; Frigerio, Alfonso; Kawai, Masaaki; Scharpantgen, Astrid; Broeders, Mireille; Hofvind, Solveig; Vidal, Carmen; Ederra, Maria; Salas, Dolores; Bulliard, Jean-Luc; Tomatis, Mariano; Kerlikowske, Karla; Taplin, Stephen

2013-01-01

Background There is concern about detection of Ductal Carcinoma in Situ (DCIS) in screening mammography. DCIS accounts for a substantial proportion of screen detected lesions but its effect on breast cancer mortality is debated. The International Cancer Screening Network conducted a comparative analysis to determine variation in DCIS detection. Patients and Methods Data were collected during 2004–2008 on number of screening examinations, detected breast cancers, DCIS cases, and Globocan 2008 breast cancer incidence rates derived from national or regional cancer registers. We calculated screen-detection rates for breast cancers and DCIS. Results Data were obtained from 15 screening settings in 12 countries; 7,176,050 screening examinations; 29,605 breast cancers; and 5,324 DCIS cases. The ratio between highest and lowest breast cancer incidence was 2.88 (95% confidence interval (CI) 2.76–3.00); 2.97 (95% CI 2.51–3.51) for detection of breast cancer; and 3.49 (95% CI 2.70–4.51) for detection of DCIS. Conclusions Considerable international variation was found in DCIS detection. This variation could not be fully explained by variation in incidence nor in breast cancer detection rates. It suggests the potential for wide discrepancies in management of DCIS resulting in overtreatment of indolent DCIS or undertreatment of potentially curable disease. Comprehensive cancer registration is needed to monitor DCIS detection. Efforts to understand discrepancies and standardize management may improve care. PMID:24041876

The extended spectrum β-lactamases (ESBL) and virulence genes of intestinal enteroaggregative Escherichia coli (EAEC) in healthy elderly individuals.

PubMed

Wang, Yuan; Wu, Jian; Cao, Yi

2015-01-01

to analyze the detection rate of intestinal enteroaggregative Escherichia coli (EAEC) in healthy elderly (≥60 years) individuals in the Hangzhou area of China, and to investigate the extended spectrum β-lactamases and virulence genes of EAEC. Stool specimens provided by healthy elderly individuals were cultured on blood agar, SS, and MAC plates. The bacterial strains were identified using Vitek-2 Compact automatic microorganism identification system and mass spectrometry. The resistance phenotypes of the bacteria were determined using the double-disk synergy method. The resistance genes and the EAEC virulence gene, astA and aggR, were amplified by PCR and compared to the sequences available in Gen Bank. Among the 1050 healthy volunteers, the majority of bacteria were E. coli, accounting for 960 strains, with an ESBL-positive rate of 36.3% (348/960). The EAEC detection rate was 10% (96/960); among them, 84 strains were astA, the detection rate of which was 8.75%; 12 strains were aggR, the detection rate of which was 1.25%. The ESBL-positive rate of EAEC strains were 56.25% (54/96), all of which carried the CTX-M type, with the CTX-M-14 predominating at 66.7% (36/54). The ESBL-positive rate of intestinal E. coli in healthy elderly individuals in the Hangzhou area of China was higher than the rate detected in other regions of china; and there was a high rate of antibiotic resistance among the intestinal EAEC in healthy elderly individuals. The results of this study suggest that EAEC is not only a pathogenic bacteria detected in diarrhea patients, but can also be present in healthy individuals, and high-resistance clinical strains have spread to the healthy population in the Hangzhou area. So vigilance is critical.

Influence of enrichment and isolation media on the detection of Campylobacter spp. in naturally contaminated chicken samples.

PubMed

Repérant, E; Laisney, M J; Nagard, B; Quesne, S; Rouxel, S; Le Gall, F; Chemaly, M; Denis, M

2016-09-01

Investigating Campylobacter epidemiology requires adequate technique and media to ensure optimal culturing and accurate detection and isolation of Campylobacter strains. In the present study, we investigated the performances of three enrichment durations in Bolton broth (0, 24 and 48h) and compared four isolation media (mCCDA, Karmali, Butzler no. 2 and CampyFood agar (CFA)) for the detection of Campylobacter positive samples and the identification of Campylobacter species, from naturally contaminated broiler chicken samples (caeca, neck skin from carcasses, and skin from thighs). We compared our local results to those we obtained with samples from a European survey (caeca and neck skin) and a national survey (neck skin, thigh skin, and breast). Direct plating favored the detection of positive samples highly contaminated by Campylobacter (caeca and neck skin from carcasses) whatever the media. A longer enrichment reduced the rates of Campylobacter recovery except when using Butzler no. 2, more particularly for neck skin which background microflora was less important than in caeca. As a matter of fact, enrichment allowed a higher detection rate of positive samples with low Campylobacter contamination levels (breast, thigh skin), this detection being enhanced when using Butzler no. 2. When comparing the 3 other selective media, CFA was the 2nd most efficient media prior to mCCDA and Karmali. Interestingly, enrichment promoted the growth of Campylobacter coli but this promotion was least with Butzler no. 2 agar. Our study has confirmed the need to adapt the method to the types of samples for improving the detection of Campylobacter and that the method may affect the prevalence of the species. Copyright © 2016 Elsevier B.V. All rights reserved.

Introduction of the colorectal cancer screening program: results from a single centre study.

PubMed

Vermeer, Nina C A; Bahadoer, Renu R; Bastiaannet, Esther; Holman, Fabian A; Meershoek-Klein Kranenbarg, Elma; Liefers, Gerrit-Jan; van de Velde, Cornelis J H; Peeters, Koen C M J

2018-06-19

In 2014, a national colorectal cancer (CRC) screening program was launched in the Netherlands. It is difficult to assess for the individual CRC patient whether the oncological benefits of surgery will outweigh the morbidity of the procedure, especially in early lesions. This study compares patient and tumour characteristics between screen-detected and non-screen-detected patients. Secondly, we present an overview of treatment options and clinical dilemmas when treating patients with early stage colorectal disease. Between January 2014 and December 2016, all patients with non-malignant polyps or CRC who were referred to the Department of Surgery of the Leiden University Medical Centre in the Netherlands were included. Baseline characteristics, type of treatment and short-term outcomes of patients with screen-detected and non-screen-detected colorectal tumours were compared. A total of 426 patients were included, of whom 240 (56.3%) were identified by screening. Non-screen-detected patients more often had comorbidity (p=0.03), the primary tumour was more often located in the rectum (p=0.001) and there was a higher rate of metastatic disease (p<0.001). Among 354 surgically treated patients, postoperative adverse events did not significantly differ between the two groups (p=0.38). Of 46 patients with T1 CRC in the endoscopic resection specimen, 23 underwent surgical resection of which only 30.4% had residual invasive disease at colectomy. Despite differences in comorbidity and stage, surgical outcome of patients with screen-detected tumours compared to non-screen-detected tumours was not significantly different. Considering its limited oncological benefits as well as the rate of adverse events, surgery for non-malignant polyps and T1 CRC should be considered carefully. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Detecting DIF in Polytomous Items Using MACS, IRT and Ordinal Logistic Regression

ERIC Educational Resources Information Center

Elosua, Paula; Wells, Craig

2013-01-01

The purpose of the present study was to compare the Type I error rate and power of two model-based procedures, the mean and covariance structure model (MACS) and the item response theory (IRT), and an observed-score based procedure, ordinal logistic regression, for detecting differential item functioning (DIF) in polytomous items. A simulation…

Decline in American marten occupancy rates at Sagehen Experimental Forest, California

Treesearch

Katie M. Moriarty; William J. Zielinski; Eric D. Forsman

2011-01-01

We compared the distribution and frequency of American marten (Martes americana) detections during historic surveys and a recent survey on the Sagehen Experimental Forest (SEF) in the Sierra Nevada Mountains, California. This area has been the location of 9 previous marten surveys during 1980–1993, each involving a systematic detection/non-...

[The detection of stable and unstable markers of radiation action in persons with a history of chronic irradiation using the methods of routine and differentiated staining of metaphase chromosomes].

PubMed

Shemetun, O V; Pilins'ka, M A

1998-01-01

A comparative cytogenetic observation of a group from Chernobyl NPP personnel has been carried out using conventional and G-banding staining. Detection rate of stable aberration by conventional staining to G-banding was 0.20.

A comparison of two tools to screen potentially inappropriate medication in internal medicine patients.

PubMed

Blanc, A-L; Spasojevic, S; Leszek, A; Théodoloz, M; Bonnabry, P; Fumeaux, T; Schaad, N

2018-04-01

Potentially inappropriate medication (PIM) is an important issue for inpatient management; it has been associated with safety problems, such as increases in adverse drugs events, and with longer hospital stays and higher healthcare costs. To compare two PIM-screening tools-STOPP/START and PIM-Check-applied to internal medicine patients. A second objective was to compare the use of PIMs in readmitted and non-readmitted patients. A retrospective observational study, in the general internal medicine ward of a Swiss non-university hospital. We analysed a random sample of 50 patients, hospitalized in 2013, whose readmission within 30 days of discharge had been potentially preventable, and compared them to a sample of 50 sex- and age-matched patients who were not readmitted. PIMs were screened using the STOPP/START tool, developed for geriatric patients, and the PIM-Check tool, developed for internal medicine patients. The time needed to perform each patient's analysis was measured. A clinical pharmacist counted and evaluated each PIM detected, based on its clinical relevance to the individual patient's case. The rates of screened and validated PIMs involving readmitted and non-readmitted patients were compared. Across the whole population, PIM-Check and STOPP/START detected 1348 and 537 PIMs, respectively, representing 13.5 and 5.4 PIMs/patient. Screening time was substantially shorter with PIM-Check than with STOPP/START (4 vs 10 minutes, respectively). The clinical pharmacist judged that 45% and 42% of the PIMs detected using PIM-Check and STOPP/START, respectively, were clinically relevant to individual patients' cases. No significant differences in the rates of detected and clinically relevant PIM were found between readmitted and non-readmitted patients. Internal medicine patients are frequently prescribed PIMs. PIM-Check's PIM detection rate was three times higher than STOPP/START's, and its screening time was shorter thanks to its electronic interface. Nearly half of the PIMs detected were judged to be non-clinically relevant, however, potentially overalerting the prescriber. These tools can, nevertheless, be considered useful in daily practice. Furthermore, the relevance of any PIM detected by these tools should always be carefully evaluated within the clinical context surrounding the individual patient. © 2017 John Wiley & Sons Ltd.

Object Detection in Natural Backgrounds Predicted by Discrimination Performance and Models

NASA Technical Reports Server (NTRS)

Ahumada, A. J., Jr.; Watson, A. B.; Rohaly, A. M.; Null, Cynthia H. (Technical Monitor)

1995-01-01

In object detection, an observer looks for an object class member in a set of backgrounds. In discrimination, an observer tries to distinguish two images. Discrimination models predict the probability that an observer detects a difference between two images. We compare object detection and image discrimination with the same stimuli by: (1) making stimulus pairs of the same background with and without the target object and (2) either giving many consecutive trials with the same background (discrimination) or intermixing the stimuli (object detection). Six images of a vehicle in a natural setting were altered to remove the vehicle and mixed with the original image in various proportions. Detection observers rated the images for vehicle presence. Discrimination observers rated the images for any difference from the background image. Estimated detectabilities of the vehicles were found by maximizing the likelihood of a Thurstone category scaling model. The pattern of estimated detectabilities is similar for discrimination and object detection, and is accurately predicted by a Cortex Transform discrimination model. Predictions of a Contrast- Sensitivity- Function filter model and a Root-Mean-Square difference metric based on the digital image values are less accurate. The discrimination detectabilities averaged about twice those of object detection.

Comparison of soft-input-soft-output detection methods for dual-polarized quadrature duobinary system

NASA Astrophysics Data System (ADS)

Chang, Chun; Huang, Benxiong; Xu, Zhengguang; Li, Bin; Zhao, Nan

2018-02-01

Three soft-input-soft-output (SISO) detection methods for dual-polarized quadrature duobinary (DP-QDB), including maximum-logarithmic-maximum-a-posteriori-probability-algorithm (Max-log-MAP)-based detection, soft-output-Viterbi-algorithm (SOVA)-based detection, and a proposed SISO detection, which can all be combined with SISO decoding, are presented. The three detection methods are investigated at 128 Gb/s in five-channel wavelength-division-multiplexing uncoded and low-density-parity-check (LDPC) coded DP-QDB systems by simulations. Max-log-MAP-based detection needs the returning-to-initial-states (RTIS) process despite having the best performance. When the LDPC code with a code rate of 0.83 is used, the detecting-and-decoding scheme with the SISO detection does not need RTIS and has better bit error rate (BER) performance than the scheme with SOVA-based detection. The former can reduce the optical signal-to-noise ratio (OSNR) requirement (at BER=10-5) by 2.56 dB relative to the latter. The application of the SISO iterative detection in LDPC-coded DP-QDB systems makes a good trade-off between requirements on transmission efficiency, OSNR requirement, and transmission distance, compared with the other two SISO methods.

Colon Capsule Endoscopy compared to Conventional Colonoscopy under routine screening conditions

PubMed Central

2010-01-01

Background Colonoscopy (CSPY) for colorectal cancer screening has several limitations. Colon Capsule Endoscopy (PillCam Colon, CCE) was compared to CSPY under routine screening conditions. Methods We performed a prospective, single-center pilot study at a University Hospital. Data were obtained from November 2007 until May 2008. Patients underwent CCE on Day 1 and CSPY on Day 2. Outcomes were evaluated regarding sensitivity and specificity of polyp detection rate, with a significance level set at >5 mm. Results 59 individuals were included in this study, the results were evaluable in 56 patients (males 34, females 22; median age 59). CCE was complete in 36 subjects. Polyp detection rate for significant polyps was 11% on CSPY and 27% on CCE. 6/56 (11%) patients had polyps on CSPY not detected on CCE (miss rate). Overall sensitivity was 79% (95% confidence interval [CI], 61 to 90), specificity was 54% (95% CI, 35 to 70), positive predictive value (PPV) was 63% and negative predictive value (NPV) was 71%. Adjusted to significance of findings, sensitivity was 50% (95% CI, 19 to 81), specificity was 76% (95% CI, 63 to 86), PPV was 20% and NPV was 93%. Conclusion In comparison to the gold standard, the sensitivity of CCE for detection of relevant polyps is low, however, the high NPV supports its role as a possible screening tool. Trial Registration NCT00991003. PMID:20565828

Preliminary study of the use of radiotracers for leak detection in industrial applications

NASA Astrophysics Data System (ADS)

Wetchagarun, S.; Petchrak, A.; Tippayakul, C.

2015-05-01

One of the most widespread uses of radiotracers in the industrial applications is the leak detection of the systems. This technique can be applied, for example, to detect leak in heat exchangers or along buried industrial pipelines. The ability to perform online investigation is one of the most important advantages of the radiotracer technique over other non-radioactive leak detection methods. In this paper, a preliminary study of the leak detection using radiotracer in the laboratory scale was presented. Br-82 was selected for this work due to its chemical property, its suitable half-life and its on-site availability. The NH4Br in the form of aqueous solution was injected into the experimental system as the radiotracer. Three NaI detectors were placed along the pipelines to measure system flow rate and to detect the leakage from the piping system. The results obtained from the radiotracer technique were compared to those measured by other methods. It is found that the flow rate obtained from the radiotracer technique agreed well with the one obtained from the flow meter. The leak rate result, however, showed discrepancy between results obtained from two different measuring methods indicating further study on leak detection was required before applying this technique in the industrial system.

Robust and Accurate Anomaly Detection in ECG Artifacts Using Time Series Motif Discovery

PubMed Central

Sivaraks, Haemwaan

2015-01-01

Electrocardiogram (ECG) anomaly detection is an important technique for detecting dissimilar heartbeats which helps identify abnormal ECGs before the diagnosis process. Currently available ECG anomaly detection methods, ranging from academic research to commercial ECG machines, still suffer from a high false alarm rate because these methods are not able to differentiate ECG artifacts from real ECG signal, especially, in ECG artifacts that are similar to ECG signals in terms of shape and/or frequency. The problem leads to high vigilance for physicians and misinterpretation risk for nonspecialists. Therefore, this work proposes a novel anomaly detection technique that is highly robust and accurate in the presence of ECG artifacts which can effectively reduce the false alarm rate. Expert knowledge from cardiologists and motif discovery technique is utilized in our design. In addition, every step of the algorithm conforms to the interpretation of cardiologists. Our method can be utilized to both single-lead ECGs and multilead ECGs. Our experiment results on real ECG datasets are interpreted and evaluated by cardiologists. Our proposed algorithm can mostly achieve 100% of accuracy on detection (AoD), sensitivity, specificity, and positive predictive value with 0% false alarm rate. The results demonstrate that our proposed method is highly accurate and robust to artifacts, compared with competitive anomaly detection methods. PMID:25688284

Detectability and Uncertainties of the Supernova Relic Neutrino Background

NASA Astrophysics Data System (ADS)

Nakazato, Ken'ichiro; Mochida, Eri; Niino, Yuu; Suzuki, Hideyuki

The spectrum of the supernova relic neutrino (SRN) background from past stellar core collapses is calculated and its detectability at SK-Gd (Super-Kamiokande experiment with gadolinium-loaded water) is investigated. Several uncertainties on the flux of SRNs are considered. The core collapse rate at each redshift depends on the cosmic star formation rate, initial mass function and mass range of progenitors that end with a core collapse. The shock revival time is introduced as a parameter that should depend on the still unknown explosion mechanism of core collapse supernovae. Furthermore, since the neutrino luminosity of black-hole-forming failed supernovae is higher than that of ordinary supernovae, their contribution to SRNs is quantitatively estimated. Assuming the mass and metallicity ranges of their progenitors, the redshift dependence of the black hole formation rate is considered on the basis of the metallicity evolution of galaxies. As a result, it is found that the expected event rate of SRNs is comparable with other backgrounds at SK-Gd. Therefore, the required observation time to detect SRNs at SK-Gd depends strongly on the core collapse rate and it is 10-300 years.

Monitoring nocturnal heart rate with bed sensor.

PubMed

Migliorini, M; Kortelainen, J M; Pärkkä, J; Tenhunen, M; Himanen, S L; Bianchi, A M

2014-01-01

This article is part of the Focus Theme of Methods of Information in Medicine on "Biosignal Interpretation: Advanced Methods for Studying Cardiovascular and Respiratory Systems". The aim of this study is to assess the reliability of the estimated Nocturnal Heart Rate (HR), recorded through a bed sensor, compared with the one obtained from standard electrocardiography (ECG). Twenty-eight sleep deprived patients were recorded for one night each through matrix of piezoelectric sensors, integrated into the mattress, through polysomnography (PSG) simultaneously. The two recording methods have been compared in terms of signal quality and differences in heart beat detection. On average, coverage of 92.7% of the total sleep time was obtained for the bed sensor, testifying the good quality of the recordings. The average beat-to-beat error of the inter-beat intervals was 1.06%. These results suggest a good overall signal quality, however, considering fast heart rates (HR > 100 bpm), performances were worse: in fact, the sensitivity in the heart beat detection was 28.4% while the false positive rate was 3.8% which means that a large amount of fast beats were not detected. The accuracy of the measurements made using the bed sensor has less than 10% of failure rate especially in periods with HR lower than 70 bpm. For fast heart beats the uncertainty increases. This can be explained by the change in morphology of the bed sensor signal in correspondence of a higher HR.

Performance of Spectrogram-Based Seizure Identification of Adult EEGs by Critical Care Nurses and Neurophysiologists.

PubMed

Amorim, Edilberto; Williamson, Craig A; Moura, Lidia M V R; Shafi, Mouhsin M; Gaspard, Nicolas; Rosenthal, Eric S; Guanci, Mary M; Rajajee, Venkatakrishna; Westover, M Brandon

2017-07-01

Continuous EEG screening using spectrograms or compressed spectral arrays (CSAs) by neurophysiologists has shorter review times with minimal loss of sensitivity for seizure detection when compared with visual analysis of raw EEG. Limited data are available on the performance characteristics of CSA-based seizure detection by neurocritical care nurses. This is a prospective cross-sectional study that was conducted in two academic neurocritical care units and involved 33 neurointensive care unit nurses and four neurophysiologists. All nurses underwent a brief training session before testing. Forty two-hour CSA segments of continuous EEG were reviewed and rated for the presence of seizures. Two experienced clinical neurophysiologists masked to the CSA data performed conventional visual analysis of the raw EEG and served as the gold standard. The overall accuracy was 55.7% among nurses and 67.5% among neurophysiologists. Nurse seizure detection sensitivity was 73.8%, and the false-positive rate was 1-per-3.2 hours. Sensitivity and false-alarm rate for the neurophysiologists was 66.3% and 1-per-6.4 hours, respectively. Interrater agreement for seizure screening was fair for nurses (Gwet AC1 statistic: 43.4%) and neurophysiologists (AC1: 46.3%). Training nurses to perform seizure screening utilizing continuous EEG CSA displays is feasible and associated with moderate sensitivity. Nurses and neurophysiologists had comparable sensitivities, but nurses had a higher false-positive rate. Further work is needed to improve sensitivity and reduce false-alarm rates.

A dual-process account of auditory change detection.

PubMed

McAnally, Ken I; Martin, Russell L; Eramudugolla, Ranmalee; Stuart, Geoffrey W; Irvine, Dexter R F; Mattingley, Jason B

2010-08-01

Listeners can be "deaf" to a substantial change in a scene comprising multiple auditory objects unless their attention has been directed to the changed object. It is unclear whether auditory change detection relies on identification of the objects in pre- and post-change scenes. We compared the rates at which listeners correctly identify changed objects with those predicted by change-detection models based on signal detection theory (SDT) and high-threshold theory (HTT). Detected changes were not identified as accurately as predicted by models based on either theory, suggesting that some changes are detected by a process that does not support change identification. Undetected changes were identified as accurately as predicted by the HTT model but much less accurately than predicted by the SDT models. The process underlying change detection was investigated further by determining receiver-operating characteristics (ROCs). ROCs did not conform to those predicted by either a SDT or a HTT model but were well modeled by a dual-process that incorporated HTT and SDT components. The dual-process model also accurately predicted the rates at which detected and undetected changes were correctly identified.

Sex-dependent modulation of ultrasonic vocalizations in house mice (Mus musculus musculus)

PubMed Central

Reitschmidt, Doris; Noll, Anton; Balazs, Peter; Penn, Dustin J.

2017-01-01

House mice (Mus musculus) emit ultrasonic vocalizations (USVs), which are surprisingly complex and have features of bird song, but their functions are not well understood. Previous studies have reported mixed evidence on whether there are sex differences in USV emission, though vocalization rate or other features may depend upon whether potential receivers are of the same or opposite sex. We recorded the USVs of wild-derived adult house mice (F1 of wild-caught Mus musculus musculus), and we compared the vocalizations of males and females in response to a stimulus mouse of the same- or opposite-sex. To detect and quantify vocalizations, we used an algorithm that automatically detects USVs (Automatic Mouse Ultrasound Detector or A-MUD). We found high individual variation in USV emission rates (4 to 2083 elements/10 min trial) and a skewed distribution, with most mice (60%) emitting few (≤50) elements. We found no differences in the rates of calling between the sexes overall, but mice of both sexes emitted vocalizations at a higher rate and higher frequencies during opposite- compared to same-sex interactions. We also observed a trend toward higher amplitudes by males when presented with a male compared to a female stimulus. Our results suggest that mice modulate the rate and frequency of vocalizations depending upon the sex of potential receivers. PMID:29236704

Effects of a School Mental Health Project: A One-Year Follow-Up

ERIC Educational Resources Information Center

Lorion, Raymond P.; And Others

1976-01-01

Matched samples of children who had (Terminators) or had not (Nonterminators) successfully participated in a school-based project for the early detection and treatment of school maladaption were compared on teacher ratings of adjustment with a control sample. Terminators were found to have more positive school adjustment ratings that…

A Saturnian gas ring and the recycling of Titan's atmosphere

NASA Technical Reports Server (NTRS)

Mcdonough, T. R.; Brice, N. M.

1973-01-01

Atoms which escape Titan's atmosphere are unlikely to possess escape velocity from Saturn and can orbit the planet until lost by ionization or collision with Titan. It is predicted that a toroidal ring of between 1 and 1,000 atoms or molecules per cubic centimeter exists around Saturn at a distance of about 10 times the radius of the visible rings. This torus may be detectable from earth orbit and detection or nondetection of it may provide some information about the presence or absence of a Saturnian magnetic field, and the exospheric temperature and atmospheric escape rate of Titan. It is estimated that, if Titan has a large exosphere, 97% or more of the escaping atoms can be recaptured by Titan, thereby decreasing the effective net atmospheric loss rate by up to two orders of magnitude. It is shown that, if Saturn has a magnetic field comparable to Jupiter's the magnetospheric plasma can supply Titan with hydrogen at a rate comparable to the loss rates in some of the models of Trafton (1972) and Sagan (1973).

The clinical value of HPV E6/E7 and STAT3 mRNA detection in cervical cancer screening.

PubMed

Fan, Yibing; Shen, Zongji

2018-05-01

To explore the value of human papillomavirus (HPV) E6/E7 and signal transducer and activator of transcription 3 (STAT3) mRNA detection in the screening of cervical lesions. 192 patients with abnormal ThinPrep cytology test (TCT) results and/or high-risk HPV infection were screened to identify possible cervical lesions in cases. Diagnoses were confirmed by histopathology. Fluorescence in situ hybridization (FISH) was performed to detect and qualify the mRNAs of HPV E6/E7, STAT3, and Survivin in cervical exfoliated cells. In addition, the performance of separate and combined mRNA detection methods were compared with TCT, HR-HPV DNA schemes respectively. 1. Compared with HPVE6/E7 and STAT3 mRNA methods, Survivin mRNA assay had poor specificity (Sp), Youden index (YI) and concordance rate. 2. HPV E6/E7, STAT3, and STAT3 + HR-HPV methods had the best Sp, concordance rate and positive predictive value (PPV) for cervical lesions screening and atypical squamous cells of undetermined significance (ASCUS) triage. For screening of high grade squamous intraepithelial lesions or greater (HSILs+), no difference was observed in the Se of mRNA detection methods in comparison with that of TCT, HR-HPV and TCT + HR-HPV, whereas the false positive rate (FPR) decreased by 41.48%/55.99%/17.19% and the colposcopy referral rate reduced by about 20.00%/25.00%/11.17%. For triage of women with ASCUS, no difference was observed in the Se of mRNA detection methods as compared to that of HR-HPV (χ 2  = 1.05, P > 0.75), while the FPR decreased by 45.83%/37.50%/41.66% and the colposcopy referral rate reduced by 32.42%/22.60%/25.28%, respectively. The Se, YI, and PPV of the combined methods increased in comparison to each method alone. 3. Compared with the TCT + HR-HPV method, HPV E6/E7 + STAT3 method had perfect Sp (95.92%) and PPV (95.40%) for screening HSILs+, the FPR and colposcopy referral rate decreased by 31.06% and 22.48% respectively. 1. The expression of HPV E6/E7 and STAT3 mRNA confirmed using FISH assay is expected to be a new method and molecular marker for cervical lesions screening. Survivin mRNA was excluded due to its poor performance. 2. HPV E6/E7, STAT3, and STAT3 +HR-HPV assays could be new approaches for cervical cancer screening and ASCUS triage, and the efficiency of combined screening program was better than that of a separate one. 3. HPV E6/E7 + STAT3 regimen is expected to be a diagnostic strategy for cervical lesions. Copyright © 2018 Elsevier GmbH. All rights reserved.

A Real-Time Wireless Sweat Rate Measurement System for Physical Activity Monitoring.

PubMed

Brueck, Andrew; Iftekhar, Tashfin; Stannard, Alicja B; Yelamarthi, Kumar; Kaya, Tolga

2018-02-10

There has been significant research on the physiology of sweat in the past decade, with one of the main interests being the development of a real-time hydration monitor that utilizes sweat. The contents of sweat have been known for decades; sweat provides significant information on the physiological condition of the human body. However, it is important to know the sweat rate as well, as sweat rate alters the concentration of the sweat constituents, and ultimately affects the accuracy of hydration detection. Towards this goal, a calorimetric based flow-rate detection system was built and tested to determine sweat rate in real time. The proposed sweat rate monitoring system has been validated through both controlled lab experiments (syringe pump) and human trials. An Internet of Things (IoT) platform was embedded, with the sensor using a Simblee board and Raspberry Pi. The overall prototype is capable of sending sweat rate information in real time to either a smartphone or directly to the cloud. Based on a proven theoretical concept, our overall system implementation features a pioneer device that can truly measure the rate of sweat in real time, which was tested and validated on human subjects. Our realization of the real-time sweat rate watch is capable of detecting sweat rates as low as 0.15 µL/min/cm², with an average error in accuracy of 18% compared to manual sweat rate readings.

Deception Detection: The Relationship of Levels of Trust and Perspective Taking in Real-Time Online and Offline Communication Environments.

PubMed

Friend, Catherine; Fox Hamilton, Nicola

2016-09-01

Where humans have been found to detect lies or deception only at the rate of chance in offline face-to-face communication (F2F), computer-mediated communication (CMC) online can elicit higher rates of trust and sharing of personal information than F2F. How do levels of trust and empathetic personality traits like perspective taking (PT) relate to deception detection in real-time CMC compared to F2F? A between groups correlational design (N = 40) demonstrated that, through a paired deceptive conversation task with confederates, levels of participant trust could predict accurate detection online but not offline. Second, participant PT abilities could not predict accurate detection in either conversation medium. Finally, this study found that conversation medium also had no effect on deception detection. This study finds support for the effects of the Truth Bias and online disinhibition in deception, and further implications in law enforcement are discussed.

Detection of spectroscopic binaries: lessons from the Gaia-ESO survey

NASA Astrophysics Data System (ADS)

van der Swaelmen, Mathieu; Merle, Thibault; van Eck, Sophie; Jorissen, Alain; Zwitter, Tomaž

2018-04-01

The Gaia-ESO survey (GES; Gilmore et al. (2012), Randich et al. (2013)) is a spectroscopic survey complementing the Gaia mission to bring accurate radial velocities and chemical abundances for 105 stars. Merle et al. (submitted to A&A see also this volume) developped a tool (DOE) to detect multiple peaks in the cross-correlation functions (CCFs) of GES spectra. Using the GIRAFFE HR10 and HR21 settings, we were able to compare the efficiency of our SB detection tool depending on the wavelength range and resolution. We show that a careful design of CCF masks can improve the detection rate in the HR21 settings. HR21 spectra are similar to the ones produced by the RVS spectrograph of the Gaia mission, though the lower resolution of RVS spectra may result in a lower detection efficiency than the case of HR21. Analysis of RVS spectra in the context of spectroscopic binaries can take advantage of the lessons learnt from the GES to maximize the detection rate.

Mortality in children with early detected congenital central hypothyroidism.

PubMed

Zwaveling-Soonawala, Nitash; Naafs, Jolanda C; Verkerk, Paul H; van Trotsenburg, A S Paul

2018-06-07

Approximately 60-80% of patients with congenital central hypothyroidism (CH-C) have multiple pituitary hormone deficiencies (MPHD), making CH-C a potentially life-threatening disease. Data on mortality in CH-C patients, however, are lacking. To study mortality rate in early detected and treated pediatric CH-C patients in the Netherlands and to investigate whether causes of death were related to pituitary hormone deficiencies. Overall mortality rate, infant mortality rate and under-5 mortality rate were calculated in all children with CH-C detected by neonatal screening between 1-1-1995 and 1-1-2013. Medical charts were reviewed to establish causes of death. 139 children with CH-C were identified, of which 138 could be traced (82 MPHD/56 isolated CHC). Total observation time was 1414 years with a median follow up duration of 10.2 years. The overall mortality rate was 10.9% (15/138). Infant mortality rate (IMR) and under-5 mortality rate were 65.2/1000 (9/138) and 101.4/1000 (14/138), respectively, compared to an IMR of 4.7/1000 and under-5 mortality of 5.4/1000 live born children in the Netherlands during the same time period (p<0.0001). Main causes of death were severe congenital malformations in six patients, asphyxia in two patients, and congenital or early neonatal infection in two patients. Pituitary hormone deficiency was noted as cause of death in only one infant. We report an increased mortality rate in early detected CH-C patients which does not seem to be related to endocrine disease. This suggests that mortality due to pituitary insufficiency is low in an early detected and treated CH-C population.

Functional magnetic resonance imaging activation detection: fuzzy cluster analysis in wavelet and multiwavelet domains.

PubMed

Jahanian, Hesamoddin; Soltanian-Zadeh, Hamid; Hossein-Zadeh, Gholam-Ali

2005-09-01

To present novel feature spaces, based on multiscale decompositions obtained by scalar wavelet and multiwavelet transforms, to remedy problems associated with high dimension of functional magnetic resonance imaging (fMRI) time series (when they are used directly in clustering algorithms) and their poor signal-to-noise ratio (SNR) that limits accurate classification of fMRI time series according to their activation contents. Using randomization, the proposed method finds wavelet/multiwavelet coefficients that represent the activation content of fMRI time series and combines them to define new feature spaces. Using simulated and experimental fMRI data sets, the proposed feature spaces are compared to the cross-correlation (CC) feature space and their performances are evaluated. In these studies, the false positive detection rate is controlled using randomization. To compare different methods, several points of the receiver operating characteristics (ROC) curves, using simulated data, are estimated and compared. The proposed features suppress the effects of confounding signals and improve activation detection sensitivity. Experimental results show improved sensitivity and robustness of the proposed method compared to the conventional CC analysis. More accurate and sensitive activation detection can be achieved using the proposed feature spaces compared to CC feature space. Multiwavelet features show superior detection sensitivity compared to the scalar wavelet features. (c) 2005 Wiley-Liss, Inc.

Incidence of childhood pneumonia: facility-based surveillance estimate compared to measured incidence in a South African birth cohort study

PubMed Central

le Roux, David M; Myer, Landon; Nicol, Mark P; Zar, Heather J

2015-01-01

Background Pneumonia is the leading cause of childhood mortality and a major contributor to childhood morbidity, but accurate measurement of pneumonia incidence is challenging. We compared pneumonia incidence using a facility-based surveillance system to estimates from a cohort study conducted contemporaneously in the same community in Cape Town, South Africa. Methods A surveillance system was developed in six public sector primary care clinics and in a regional referral hospital, to detect childhood pneumonia cases. Nurses recorded all children presenting to facilities who met WHO case definitions of pneumonia, and hospital records were reviewed. Estimates of pneumonia incidence and severity were compared with incidence rates based on active surveillance in the Drakenstein Child Health Study. Results From June 2012 until September 2013, the surveillance system detected 306 pneumonia episodes in children under 1 year of age, an incidence of 0.20 episodes/child-year (e/cy) (95% CI 0.17 to 0.22 e/cy). The incidence in the cohort study from the same period was 0.27 e/cy (95% CI 0.23 to 0.32 e/cy). Pneumonia incidence in the surveillance system was almost 30% lower than in the birth cohort; incidence rate ratio 0.72 (95% CI 0.58 to 0.89). In the surveillance system, 18% were severe pneumonia cases, compared to 23% in the birth cohort, rate ratio 0.81 (95% CI 0.55 to 1.18). Conclusions In this setting, facility-based pneumonia surveillance detected fewer cases of pneumonia, and fewer severe cases, compared to the corresponding cohort study. Facility pneumonia surveillance using data collected by local healthcare workers provides a useful estimate of the epidemiology of childhood pneumonia but may underestimate incidence and severity. PMID:26685027

Internalization and dissemination of human norovirus and Tulane virus in fresh produce is plant dependent.

PubMed

Yang, Zhihong; Chambers, Heather; DiCaprio, Erin; Gao, Gary; Li, Jianrong

2018-02-01

Human norovirus (NoV) is a leading cause of fresh produce associated outbreaks. Previous research indicates that the roots of growing leafy greens and berries internalize human NoV. However the effect of plant type and inoculum level on internalization rates has not been directly compared. In this study we compared the internalization and dissemination rates of human NoV and its surrogate, Tulane virus (TV) in green onion, radishes, and Romaine lettuce. We also evaluated the effect inoculum level and plant growth matrix on the rate of viral internalization. In the hydroponic growth system, we detected internalization and dissemination of human NoV RNA in green onions. In hydroponically growing green onions inoculated with high titer TV, we found higher rates of internalization and dissemination compared to green onions inoculated with low titer TV. In soil growth systems, no infectious TV was detected in either green onion or radishes. However, in Romaine lettuce plants grown in soil approximately 4 log 10  PFU/g was recovered from all tissues on day 14 p.i. Overall, we found that the type of plant, growth matrix, and the inoculum level influences the internalization and dissemination of human NoV and TV. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparing near-regional and local measurements of infrasound from Mount Erebus, Antarctica: Implications for monitoring

NASA Astrophysics Data System (ADS)

Dabrowa, A. L.; Green, D. N.; Johnson, J. B.; Phillips, J. C.; Rust, A. C.

2014-11-01

Local (100 s of metres from vent) monitoring of volcanic infrasound is a common tool at volcanoes characterized by frequent low-magnitude eruptions, but it is generally not safe or practical to have sensors so close to the vent during more intense eruptions. To investigate the potential and limitations of monitoring at near-regional ranges (10 s of km) we studied infrasound detection and propagation at Mount Erebus, Antarctica. This site has both a good local monitoring network and an additional International Monitoring System infrasound array, IS55, located 25 km away. We compared data recorded at IS55 with a set of 117 known Strombolian events that were recorded with the local network in January 2006. 75% of these events were identified at IS55 by an analyst looking for a pressure transient coincident with an F-statistic detection, which identifies coherent infrasound signals. With the data from January 2006, we developed and calibrated an automated signal-detection algorithm based on threshold values of both the F-statistic and the correlation coefficient. Application of the algorithm across IS55 data for all of 2006 identified infrasonic signals expected to be Strombolian explosions, and proved reliable for indicating trends in eruption frequency. However, detectability at IS55 of known Strombolian events depended strongly on the local signal amplitude: 90% of events with local amplitudes > 25 Pa were identified at IS55, compared to only 26% of events with local amplitudes < 25 Pa. Event detection was also affected by considerable variation in amplitude decay rates between the local and near-regional sensors. Amplitudes recorded at IS55 varied between 3% and 180% of the amplitude expected assuming hemispherical spreading, indicating that amplitudes recorded at near-regional ranges to Erebus are unreliable indicators of event magnitude. Comparing amplitude decay rates with locally collected radiosonde data indicates a close relationship between recorded amplitude and lower atmosphere effective sound speed structure. At times of increased sound speed gradient, higher amplitude decay rates are observed, consistent with increased upward refraction of acoustic energy along the propagation path. This study indicates that whilst monitoring activity levels at near-regional ranges can be successful, variable amplitude decay rate means quantitative analysis of infrasound data for eruption intensity and magnitude is not advisable without the consideration of local atmospheric sound speed structure.

Detection of chikungunya virus in saliva and urine.

PubMed

Musso, Didier; Teissier, Anita; Rouault, Eline; Teururai, Sylviane; de Pina, Jean-Jacques; Nhan, Tu-Xuan

2016-06-16

Saliva and urine have been used for arthropod-borne viruses molecular detection but not yet for chikungunya virus (CHIKV). We investigated the use of saliva and urine for molecular detection of CHIKV during the French Polynesian outbreak. During the French Polynesian chikungunya outbreak (2014-2015), we collected the same day blood and saliva samples from 60 patients with probable chikungunya (47 during the 1st week post symptoms onset and 13 after), urine was available for 39 of them. All samples were tested using a CHIKV reverse-transcription PCR. Forty eight patients had confirmed chikungunya. For confirmed chikungunya presenting during the 1st week post symptoms onset, CHIKV RNA was detected from 86.1 % (31/36) of blood, 58.3 % (21/36) of saliva and 8.3 % (2/24) of urine. Detection rate of CHIKV RNA was significantly higher in blood compared to saliva. For confirmed chikungunya presenting after the 1st week post symptoms onset, CHIKV RNA was detected from 8.3 % (1/12) of blood, 8.3 % (1/12) of saliva and 0 % (0/8) of urine. In contrast to Zika virus (ZIKV), saliva did not increased the detection rate of CHIKV RNA during the 1st week post symptoms onset. In contrast to ZIKV, dengue virus and West Nile virus, urine did not enlarged the window of detection of CHIKV RNA after the 1st week post symptoms onset. Saliva can be used for molecular detection of CHIKV during the 1st week post symptoms onset only if blood is impossible to collect but with a lower sensitivity compared to blood.

Carcass Persistence and Detectability: Reducing the Uncertainty Surrounding Wildlife-Vehicle Collision Surveys

PubMed Central

Santos-Reis, Margarida; Picanço de Figueiredo, Almir; Bager, Alex; Aguiar, Ludmilla M. S.

2016-01-01

Carcass persistence time and detectability are two main sources of uncertainty on roadkill surveys. In this study, we evaluate the influence of these uncertainties on roadkill surveys and estimates. To estimate carcass persistence time, three observers (including the driver) surveyed 114km by car on a monthly basis for two years, searching for wildlife-vehicle collisions (WVC). Each survey consisted of five consecutive days. To estimate carcass detectability, we randomly selected stretches of 500m to be also surveyed on foot by two other observers (total 292 walked stretches, 146 km walked). We expected that body size of the carcass, road type, presence of scavengers and weather conditions to be the main drivers influencing the carcass persistence times, but their relative importance was unknown. We also expected detectability to be highly dependent on body size. Overall, we recorded low median persistence times (one day) and low detectability (<10%) for all vertebrates. The results indicate that body size and landscape cover (as a surrogate of scavengers’ presence) are the major drivers of carcass persistence. Detectability was lower for animals with body mass less than 100g when compared to carcass with higher body mass. We estimated that our recorded mortality rates underestimated actual values of mortality by 2–10 fold. Although persistence times were similar to previous studies, the detectability rates here described are very different from previous studies. The results suggest that detectability is the main source of bias across WVC studies. Therefore, more than persistence times, studies should carefully account for differing detectability when comparing WVC studies. PMID:27806125

Impact of Mandatory Carbon Monoxide Alarms: An Investigation of the Effects on Detection and Poisoning Rates in New York City

PubMed Central

Wheeler-Martin, Katherine; Soghoian, Sari; Manini, Alex F.; Marker, Elizabeth; Stajic, Marina; Prezant, David; Nelson, Lewis S.; Hoffman, Robert S.

2015-01-01

Objectives. We sought to evaluate the impact of New York City’s (NYC’s) 2004 carbon monoxide (CO) alarm legislation on CO incident detection and poisoning rates. Methods. We compared CO poisoning deaths, hospitalizations, exposures reported to Poison Control, and fire department investigations, before and after the law for 2000 to 2010. Use of CO alarms was assessed in the 2009 NYC Community Health Survey. Results. Investigations that found indoor CO levels greater than 9 parts per million increased nearly 7-fold after the law (P < .001). There were nonsignificant decreases in unintentional, nonfire-related CO poisoning hospitalization rates (P = .114) and death rates (P = .216). After we controlled for ambient temperature, the law’s effect on hospitalizations remained nonsignificantly protective (incidence rate ratio = 0.747; 95% confidence interval = 0.520, 1.074). By 2009, 83% of NYC residents reported having CO alarms; only 54% also recently tested or replaced their batteries. Conclusions. Mandating CO alarms significantly increased the detection of potentially hazardous CO levels in NYC homes. Small numbers and detection bias might have limited the discovery of significant decreases in poisoning outcomes. Investigation of individual poisoning circumstances since the law might elucidate remaining gaps in awareness and proper use of CO alarms. PMID:26066948

Rickettsia parkeri and "Candidatus Rickettsia andeanae" in Questing Amblyomma maculatum (Acari: Ixodidae) From Mississippi.

PubMed

Lee, J K; Moraru, G M; Stokes, J V; Wills, R W; Mitchell, E; Unz, E; Moore-Henderson, B; Harper, A B; Varela-Stokes, A S

2017-03-01

Amblyomma maculatum Koch (Acari: Ixodidae), the primary vector for Rickettsia parkeri, may also be infected with a rickettsia of unknown pathogenicity, "Candidatus Rickettsia andeanae." Infection rates with these rickettsiae vary geographically, and coinfected ticks have been reported. In this study, infection rates of R. parkeri and "Ca. R. andeanae" were evaluated, and rickettsial DNA levels quantified, in 335 questing adult A. maculatum collected in 2013 (n = 95), 2014 (n = 139), and 2015 (n = 101) from Oktibbeha County, MS. Overall infection rates of R. parkeri and "Ca. R. andeanae" were 28.7% and 9.3%, respectively, with three additional A. maculatum (0.9%) coinfected. While R. parkeri-infected ticks were detected all three years (34.7% in 2013; 13.7% in 2014; 43.6% in 2015), "Ca. R. andeanae" was not detected in 2013, and was detected at rates of 10.8% in 2014, and 15.8% in 2015. Interestingly, rickettsial DNA levels in singly-infected ticks were significantly lower in "Ca. R. andeanae"-infected ticks compared to R. parkeri-infected ticks (P < 0.0001). Thus, both infection rates and rickettsial DNA levels were higher for R. parkeri than "Ca. R. andeanae." Infection rates of R. parkeri were also higher, and "Ca. R. andeanae" lower, here compared to A. maculatum reported previously in Kansas and Oklahoma. As we continue to monitor infection rates and levels, we anticipate that understanding temporal changes will improve our awareness of human risk for spotted fever rickettsioses. Further, these data may lead to additional studies to evaluate potential interactions among sympatric Rickettsia species in A. maculatum at the population level. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Comparison of two- and six-minute walk tests in detecting oxygen desaturation in patients with severe chronic obstructive pulmonary disease — A randomized crossover trial

PubMed Central

Teschler, Sebastian; Jarosch, Inga; Christle, Jeffrey W; Hitzl, Wolfgang; Kenn, Klaus

2016-01-01

The two-minute walk test (2MWT) is less well validated than the well-known six-minute walk test (6MWT) as a field walking test in patients with chronic obstructive pulmonary disease (COPD). The primary objective of this study was to compare the accuracy of the 2MWT to the 6MWT in detecting exercise-induced oxygen desaturation in patients with severe COPD. Twenty-six patients with COPD (age: 61 ± 10 years, forced expired volume in one second: 37 ± 10%) that were normoxemic at rest performed a 2MWT and a 6MWT under normal ambient conditions on two consecutive days in random order. Oxygen saturation, total walking distance, heart rate, breathing frequency, dyspnea, and leg fatigue were evaluated. Average walking distances were 150 m (95% confidence interval (95% CI): 134–165 m) and 397 m (95% CI: 347–447 m) for the 2MWT and 6MWT, respectively (r = 0.80, p < 0.0001). The difference in minimum oxygen saturation during the 2MWT (83%, 95% CI: 81–86%) and 6MWT (mean 82%, 95% CI: 80–84%) was not statistically different and the data strongly correlated between the groups (r = 0.81, p < 0.0001). Other measurements from the 6MWT, including heart rate, breathing rate, and levels of perceived exertion were also comparable in 2MWT. The 2MWT showed comparable validity in detecting exercise-induced oxygen desaturation in patients with severe COPD compared to the 6MWT. PMID:26961775

Comparison of two- and six-minute walk tests in detecting oxygen desaturation in patients with severe chronic obstructive pulmonary disease - A randomized crossover trial.

PubMed

Gloeckl, Rainer; Teschler, Sebastian; Jarosch, Inga; Christle, Jeffrey W; Hitzl, Wolfgang; Kenn, Klaus

2016-03-08

The two-minute walk test (2MWT) is less well validated than the well-known six-minute walk test (6MWT) as a field walking test in patients with chronic obstructive pulmonary disease (COPD). The primary objective of this study was to compare the accuracy of the 2MWT to the 6MWT in detecting exercise-induced oxygen desaturation in patients with severe COPD. Twenty-six patients with COPD (age: 61 ± 10 years, forced expired volume in one second: 37 ± 10%) that were normoxemic at rest performed a 2MWT and a 6MWT under normal ambient conditions on two consecutive days in random order. Oxygen saturation, total walking distance, heart rate, breathing frequency, dyspnea, and leg fatigue were evaluated. Average walking distances were 150 m (95% confidence interval (95% CI): 134-165 m) and 397 m (95% CI: 347-447 m) for the 2MWT and 6MWT, respectively (r = 0.80, p < 0.0001). The difference in minimum oxygen saturation during the 2MWT (83%, 95% CI: 81-86%) and 6MWT (mean 82%, 95% CI: 80-84%) was not statistically different and the data strongly correlated between the groups (r = 0.81, p < 0.0001). Other measurements from the 6MWT, including heart rate, breathing rate, and levels of perceived exertion were also comparable in 2MWT. The 2MWT showed comparable validity in detecting exercise-induced oxygen desaturation in patients with severe COPD compared to the 6MWT. © The Author(s) 2016.

Results of the first continuous meteor head echo survey at polar latitudes

NASA Astrophysics Data System (ADS)

Schult, Carsten; Stober, Gunter; Janches, Diego; Chau, Jorge L.

2017-11-01

We present the first quasi continuous meteor head echo measurements obtained during a period of over two years using the Middle Atmosphere ALOMAR Radar System (MAARSY). The measurements yield information on the altitude, trajectory, vector velocity, radar cross section, deceleration and dynamical mass of every single event. The large statistical amount of nearly one million meteor head detections provide an excellent overview of the elevation, altitude, velocity and daily count rate distributions during different times of the year at polar latitudes. Only 40% of the meteors were detected within the full width half maximum of the specific sporadic meteor sources. Our observation of the sporadic meteors are compared to the observations with other radar systems and a meteor input function (MIF). The best way to compare different radar systems is by comparing the radar cross section (RCS), which is the main detection criterion for each system. In this study we aim to compare our observations with a MIF, which provides information only about the meteoroid mass. Thus, we are using a statistical approach for the elevation and velocity dependent visibility and a specific mass selection. The predicted absolute count rates from the MIF are in a good agreement with the observation when it is assumed that the radar system is only sensitive to meteoroids with masses higher than one microgram. The analysis of the dynamic masses seems to be consistent with this assumption since the count rate of events with smaller masses are low and decrease even more by using events with relatively small errors.

Role of Computer Aided Diagnosis (CAD) in the detection of pulmonary nodules on 64 row multi detector computed tomography.

PubMed

Prakashini, K; Babu, Satish; Rajgopal, K V; Kokila, K Raja

2016-01-01

To determine the overall performance of an existing CAD algorithm with thin-section computed tomography (CT) in the detection of pulmonary nodules and to evaluate detection sensitivity at a varying range of nodule density, size, and location. A cross-sectional prospective study was conducted on 20 patients with 322 suspected nodules who underwent diagnostic chest imaging using 64-row multi-detector CT. The examinations were evaluated on reconstructed images of 1.4 mm thickness and 0.7 mm interval. Detection of pulmonary nodules, initially by a radiologist of 2 years experience (RAD) and later by CAD lung nodule software was assessed. Then, CAD nodule candidates were accepted or rejected accordingly. Detected nodules were classified based on their size, density, and location. The performance of the RAD and CAD system was compared with the gold standard that is true nodules confirmed by consensus of senior RAD and CAD together. The overall sensitivity and false-positive (FP) rate of CAD software was calculated. Of the 322 suspected nodules, 221 were classified as true nodules on the consensus of senior RAD and CAD together. Of the true nodules, the RAD detected 206 (93.2%) and 202 (91.4%) by the CAD. CAD and RAD together picked up more number of nodules than either CAD or RAD alone. Overall sensitivity for nodule detection with the CAD program was 91.4%, and FP detection per patient was 5.5%. The CAD showed comparatively higher sensitivity for nodules of size 4-10 mm (93.4%) and nodules in hilar (100%) and central (96.5%) location when compared to RAD's performance. CAD performance was high in detecting pulmonary nodules including the small size and low-density nodules. CAD even with relatively high FP rate, assists and improves RAD's performance as a second reader, especially for nodules located in the central and hilar region and for small nodules by saving RADs time.

Sad Facial Expressions Increase Choice Blindness

PubMed Central

Wang, Yajie; Zhao, Song; Zhang, Zhijie; Feng, Wenfeng

2018-01-01

Previous studies have discovered a fascinating phenomenon known as choice blindness—individuals fail to detect mismatches between the face they choose and the face replaced by the experimenter. Although previous studies have reported a couple of factors that can modulate the magnitude of choice blindness, the potential effect of facial expression on choice blindness has not yet been explored. Using faces with sad and neutral expressions (Experiment 1) and faces with happy and neutral expressions (Experiment 2) in the classic choice blindness paradigm, the present study investigated the effects of facial expressions on choice blindness. The results showed that the detection rate was significantly lower on sad faces than neutral faces, whereas no significant difference was observed between happy faces and neutral faces. The exploratory analysis of verbal reports found that participants who reported less facial features for sad (as compared to neutral) expressions also tended to show a lower detection rate of sad (as compared to neutral) faces. These findings indicated that sad facial expressions increased choice blindness, which might have resulted from inhibition of further processing of the detailed facial features by the less attractive sad expressions (as compared to neutral expressions). PMID:29358926

Sad Facial Expressions Increase Choice Blindness.

PubMed

Wang, Yajie; Zhao, Song; Zhang, Zhijie; Feng, Wenfeng

2017-01-01

Previous studies have discovered a fascinating phenomenon known as choice blindness-individuals fail to detect mismatches between the face they choose and the face replaced by the experimenter. Although previous studies have reported a couple of factors that can modulate the magnitude of choice blindness, the potential effect of facial expression on choice blindness has not yet been explored. Using faces with sad and neutral expressions (Experiment 1) and faces with happy and neutral expressions (Experiment 2) in the classic choice blindness paradigm, the present study investigated the effects of facial expressions on choice blindness. The results showed that the detection rate was significantly lower on sad faces than neutral faces, whereas no significant difference was observed between happy faces and neutral faces. The exploratory analysis of verbal reports found that participants who reported less facial features for sad (as compared to neutral) expressions also tended to show a lower detection rate of sad (as compared to neutral) faces. These findings indicated that sad facial expressions increased choice blindness, which might have resulted from inhibition of further processing of the detailed facial features by the less attractive sad expressions (as compared to neutral expressions).

Factors associated with depression detection in a New Hampshire mental health outreach program.

PubMed

Ghesquiere, Angela R; Pepin, Renee; Kinsey, Jennifer; Bartels, Stephen J; Bruce, Martha L

2017-08-16

For mental health outreach programs for older adults, accurately detecting depression is key to quality service provision. Multiple factors, including gender, cognitive impairment, or recent bereavement may affect depression detection, but this is under-studied. Therefore, we sought to both establish rates of depressive symptom detection and to examine factors associated with inaccuracies of detecting depression among participants in a mental health outreach program serving older adults. We conducted a chart review of 1126 cases in an older adult-focused mental health outreach program in New Hampshire, the Referral Education Assistance & Prevention (REAP) program. Accuracy of depression detection was identified by comparing screen-positive scores for depressive symptoms on the 15-item Geriatric Depression Scale (GDS) to depression identification by counselors on a 'presenting concerns' list. Inaccurate depression detection (positive on the GDS but depression not identified by counselors) occurred in 27.6% of cases. Multivariate regression analyses indicated that anxiety, cognitive concerns, and rurality were all associated with detection innaccuracy. This study appears to be the first to examine factors influencing depression detection in a mental health outreach program. Future efforts should help ensure that all older mental health outreach clients have depression detected at optimal rates.

Detection experiments with humans implicate visual predation as a driver of colour polymorphism dynamics in pygmy grasshoppers

PubMed Central

2013-01-01

Background Animal colour patterns offer good model systems for studies of biodiversity and evolution of local adaptations. An increasingly popular approach to study the role of selection for camouflage for evolutionary trajectories of animal colour patterns is to present images of prey on paper or computer screens to human ‘predators’. Yet, few attempts have been made to confirm that rates of detection by humans can predict patterns of selection and evolutionary modifications of prey colour patterns in nature. In this study, we first analyzed encounters between human ‘predators’ and images of natural black, grey and striped colour morphs of the polymorphic Tetrix subulata pygmy grasshoppers presented on background images of unburnt, intermediate or completely burnt natural habitats. Next, we compared detection rates with estimates of capture probabilities and survival of free-ranging grasshoppers, and with estimates of relative morph frequencies in natural populations. Results The proportion of grasshoppers that were detected and time to detection depended on both the colour pattern of the prey and on the type of visual background. Grasshoppers were detected more often and faster on unburnt backgrounds than on 50% and 100% burnt backgrounds. Striped prey were detected less often than grey or black prey on unburnt backgrounds; grey prey were detected more often than black or striped prey on 50% burnt backgrounds; and black prey were detected less often than grey prey on 100% burnt backgrounds. Rates of detection mirrored previously reported rates of capture by humans of free-ranging grasshoppers, as well as morph specific survival in the wild. Rates of detection were also correlated with frequencies of striped, black and grey morphs in samples of T. subulata from natural populations that occupied the three habitat types used for the detection experiment. Conclusions Our findings demonstrate that crypsis is background-dependent, and implicate visual predation as an important driver of evolutionary modifications of colour polymorphism in pygmy grasshoppers. Our study provides the clearest evidence to date that using humans as ‘predators’ in detection experiments may provide reliable information on the protective values of prey colour patterns and of natural selection and microevolution of camouflage in the wild. PMID:23639215

Detection of Mycobacterium tuberculosis Complex in Paraffin-Embedded Tissues by the New Automated Abbott RealTime MTB Assay.

PubMed

Fu, Yung-Chieh; Liao, I-Chuang; Chen, Hung-Mo; Yan, Jing-Jou

2016-07-01

The Abbott RealTime MTB assay, launched in June 2014, has been shown to have a competitive performance in the detection of the Mycobacterium tuberculosis (MTB) complex in respiratory specimens. The present study was conducted to investigate the usefulness of the Abbott MTB Realtime assay in the detection of MTB in formalin-fixed paraffin-embedded (FFPE) tissues. A total of 96 FFPE specimens obtained from microbiologically proven MTB cases (N=60) and nontuberculous Mycobacterium cases (N=36) were analyzed. The performance of the Abbott MTB Realtime assay was compared with that of the Roche Cobas TaqMan MTB assay. The overall sensitivity and specificity of the Abbott assay were 63.3% and 97.2%, respectively, compared with 11.7% and 100% for the Cobas assay. The detection rate of the Abbott assay was much higher among 37 acid-fast-positive specimens than among 23 acid-fast-negative specimens (89.3% versus 21.7%, respectively). The detection rate of the assay was higher among 29 resection specimens than among 31 small biopsy specimens (86.2% versus 41.9%, respectively). Our results suggest that the Abbott RealTime MTB assay can be used to differentiate MTB from nontuberculous mycobacterial infections in acid-fast-positive FFPE tissues. © 2016 by the Association of Clinical Scientists, Inc.

Projected future impact of HPV vaccination and primary HPV screening on cervical cancer rates from 2017-2035: Example from Australia.

PubMed

Hall, Michaela T; Simms, Kate T; Lew, Jie-Bin; Smith, Megan A; Saville, Marion; Canfell, Karen

2018-01-01

Many countries are transitioning from cytology-based to longer-interval HPV screening. Trials comparing HPV-based screening to cytology report an increase in CIN2/3 detection at the first screen, and longer-term reductions in CIN3+; however, population level year-to-year transitional impacts are poorly understood. We undertook a comprehensive evaluation of switching to longer-interval primary HPV screening in the context of HPV vaccination. We used Australia as an example setting, since Australia will make this transition in December 2017. Using a model of HPV vaccination, transmission, natural history and cervical screening, Policy1-Cervix, we simulated the planned transition from recommending cytology every two years for sexually-active women aged 18-20 to 69, to recommending HPV screening every five years for women aged 25-74 years. We estimated rates of CIN2/3, cervical cancer incidence, and mortality for each year from 2005 to 2035, considering ranges for HPV test accuracy and screening compliance in the context of HPV vaccination (current coverage ~82% in females; ~76% in males). Transient increases are predicted to occur in rates of CIN2/3 detection and invasive cervical cancer in the first two to three years following the screening transition (of 16-24% and 11-14% in respectively, compared to 2017 rates). However, by 2035, CIN2/3 and invasive cervical cancer rates are predicted to fall by 40-44% and 42-51%, respectively, compared to 2017 rates. Cervical cancer mortality rates are predicted to remain unchanged until ~2020, then decline by 34-45% by 2035. Over the period 2018-2035, switching to primary HPV screening in Australia is expected to avert 2,006 cases of invasive cervical cancer and save 587 lives. Transient increases in detected CIN2/3 and invasive cancer, which may be detectable at the population level, are predicted following a change to primary HPV screening. This is due to improved test sensitivity bringing forward diagnoses, resulting in longer term reductions in both cervical cancer incidence and mortality. Fluctuations in health outcomes due to the transition to a longer screening interval are predicted to occur for 10-15 years, but cervical cancer rates will be significantly reduced thereafter due to the impact of HPV vaccination and HPV screening. In order to maintain confidence in primary HPV screening through the transitional phase, it is important to widely communicate that an initial increase in CIN2/3 and perhaps even invasive cervical cancer is expected after a national transition to primary HPV screening, that this phenomenon is due to increased prevalent disease detection, and that this effect represents a marker of screening success.

Impaired search for orientation but not color in hemi-spatial neglect.

PubMed

Wilkinson, David; Ko, Philip; Milberg, William; McGlinchey, Regina

2008-01-01

Patients with hemi-spatial neglect have trouble finding targets defined by a conjunction of visual features. The problem is widely believed to stem from a high-level deficit in attentional deployment, which in turn has led to disagreement over whether the detection of basic features is also disrupted. If one assumes that the detection of salient visual features can be based on the output of spared 'preattentive' processes (Treisman and Gelade, 1980), then feature detection should remain intact. However, if one assumes that all forms of detection require at least a modicum of focused attention (Duncan and Humphreys, 1992), then all forms of search will be disrupted to some degree. Here we measured the detection of feature targets that were defined by either a unique color or orientation. Comparable detection rates were observed in non-neglected space, which indicated that both forms of search placed similar demands on attention. For either of the above accounts to be true, the two targets should therefore be detected with equal efficiency in the neglected field. We found that while the detection rate for color was normal in four of our five patients, all showed an increased reaction time and/or error rate for orientation. This result points to a selective deficit in orientation discrimination, and implies that neglect disrupts specific feature representations. That is, the effects of neglect on visual search are not only attentional but also perceptual.

A visible light imaging device for cardiac rate detection with reduced effect of body movement

NASA Astrophysics Data System (ADS)

Jiang, Xiaotian; Liu, Ming; Zhao, Yuejin

2014-09-01

A visible light imaging system to detect human cardiac rate is proposed in this paper. A color camera and several LEDs, acting as lighting source, were used to avoid the interference of ambient light. From people's forehead, the cardiac rate could be acquired based on photoplethysmography (PPG) theory. The template matching method was used after the capture of video. The video signal was discomposed into three signal channels (RGB) and the region of interest was chosen to take the average gray value. The green channel signal could provide an excellent waveform of pulse wave on the account of green lights' absorptive characteristics of blood. Through the fast Fourier transform, the cardiac rate was exactly achieved. But the research goal was not just to achieve the cardiac rate accurately. With the template matching method, the effects of body movement are reduced to a large extent, therefore the pulse wave can be detected even while people are in the moving state and the waveform is largely optimized. Several experiments are conducted on volunteers, and the results are compared with the ones gained by a finger clamped pulse oximeter. The contrast results between these two ways are exactly agreeable. This method to detect the cardiac rate and the pulse wave largely reduces the effects of body movement and can probably be widely used in the future.

Cell-Free DNA Analysis in Maternal Blood: Differences in Estimates between Laboratories with Different Methodologies Using a Propensity Score Approach.

PubMed

Bevilacqua, Elisa; Jani, Jacques C; Letourneau, Alexandra; Duiella, Silvia F; Kleinfinger, Pascale; Lohmann, Laurence; Resta, Serena; Cos Sanchez, Teresa; Fils, Jean-François; Mirra, Marilyn; Benachi, Alexandra; Costa, Jean-Marc

2018-06-13

To evaluate the failure rate and performance of cell-free DNA (cfDNA) testing, mainly in terms of detection rates for trisomy 21, performed by 2 laboratories using different analytical methods. cfDNA testing was performed on 2,870 pregnancies with the HarmonyTM Prenatal Test using the targeted digital analysis of selected regions (DANSR) method, and on 2,635 pregnancies with the "Cerba test" using the genome-wide massively parallel sequencing (GW-MPS) method, with available outcomes. Propensity score analysis was used to match patients between the 2 groups. A comparison of the detection rates for trisomy 21 between the 2 laboratories was made. In all, 2,811 patients in the Harmony group and 2,530 patients in the Cerba group had no trisomy 21, 18, or 13. Postmatched comparisons of the patient characteristics indicated a higher no-result rate in the Harmony group (1.30%) than in the Cerba group (0.75%; p = 0.039). All 41 cases of trisomy 21 in the Harmony group and 93 cases in the Cerba group were detected. Both methods of cfDNA testing showed low no-result rates and a comparable performance in detecting trisomy 21; yet GW-MPS had a slightly lower no-result rate than the DANSR method. © 2018 S. Karger AG, Basel.

Fetal heart rate deceleration detection using a discrete cosine transform implementation of singular spectrum analysis.

PubMed

Warrick, P A; Precup, D; Hamilton, E F; Kearney, R E

2007-01-01

To develop a singular-spectrum analysis (SSA) based change-point detection algorithm applicable to fetal heart rate (FHR) monitoring to improve the detection of deceleration events. We present a method for decomposing a signal into near-orthogonal components via the discrete cosine transform (DCT) and apply this in a novel online manner to change-point detection based on SSA. The SSA technique forms models of the underlying signal that can be compared over time; models that are sufficiently different indicate signal change points. To adapt the algorithm to deceleration detection where many successive similar change events can occur, we modify the standard SSA algorithm to hold the reference model constant under such conditions, an approach that we term "base-hold SSA". The algorithm is applied to a database of 15 FHR tracings that have been preprocessed to locate candidate decelerations and is compared to the markings of an expert obstetrician. Of the 528 true and 1285 false decelerations presented to the algorithm, the base-hold approach improved on standard SSA, reducing the number of missed decelerations from 64 to 49 (21.9%) while maintaining the same reduction in false-positives (278). The standard SSA assumption that changes are infrequent does not apply to FHR analysis where decelerations can occur successively and in close proximity; our base-hold SSA modification improves detection of these types of event series.

Prostate cancer detection in patients with prior negative biopsy undergoing cognitive-, robotic- or in-bore MRI target biopsy.

PubMed

Kaufmann, Sascha; Russo, Giorgio I; Bamberg, Fabian; Löwe, Lorenz; Morgia, Giuseppe; Nikolaou, Konstantin; Stenzl, Arnulf; Kruck, Stephan; Bedke, Jens

2018-05-01

To evaluate the detection rate among three different targeted biopsy approaches of robot-assisted MRI/TRUS fusion (RA-TB), mpMRI in-bore (MRGB), cognitive fusion guidance biopsy (COG-TB) for the detection of prostate cancer (PC) and clinically significant PC (csPC). Between 2014 and 2016, 156 patients with a lesion on mpMRI, performed in accordance with ESUR guidelines, due to cancer suspicion or on-going cancer suspicion after prior negative prostate biopsy, underwent targeted biopsy with RA-TB, MRGB or COG-TB. All lesions were rated according to PI-RADS v2. We compared detection rates between techniques. Models were constructed to predict the detection of overall PC and csPC and using a 1000 boot-strap sample. In the all cohort, 73, 45 and 38 patients underwent RA-TB, MRGB or COG-TB, respectively. Overall PC was found in 39 (52.42%), 23 (51.11%) and 11 (28.95%) (p = 0.04) patients of RA-TB, MRGB and COG-TB arm, respectively. As concerning the detection of csPC, it was found in 26 (35.62%),18 (40.0%) and 9 (23.68%) patients of RA-TB, MRGB and COG-TB arm (p = 0.27). Model 1 showed that RA-TB [OR: 10.08 (95% CI 1.95-51.97); p < 0.01] and MRGB [OR: 12.88 (95% CI 2.36-70.25); p < 0.01] were associated with overall PC detection in TB, while only MRGB was associated with csPC at TB (model 2) [OR: 5.72; (95% CI 1.40-23.35); p < 0.01]. The c-index for model 1 and model 2 was 0.86 and 0.85, respectively. We did not report significant complications between groups. In-bore biopsy and MRI/TRUS fusion-guided biopsy showed greater accuracy in detecting PC compared to cognitive fusion as modeled in a newly established normogram.

Detection of cardiac activity using a 5.8 GHz radio frequency sensor.

PubMed

Vasu, V; Fox, N; Brabetz, T; Wren, M; Heneghan, C; Sezer, S

2009-01-01

A 5.8-GHz ISM-Band radio-frequency sensor has been developed for non-contact measurement of respiration and heart rate from stationary and semi-stationary subjects at a distance of 0.5 to 1.5 meters. We report on the accuracy of the heart rate measurements obtained using two algorithmic approaches, as compared to a reference heart rate obtained using a pulse oximeter. Simultaneous Photoplethysmograph (PPG) and non-contact sensor recordings were recorded over fifteen minute periods for ten healthy subjects (8M/2F, ages 29.6 + or - 5.6 yrs) One algorithm is based on automated detection of individual peaks associated with each cardiac cycle; a second algorithm extracts a heart rate over a 60-second period using spectral analysis. Peaks were also extracted manually for comparison with the automated method. The peak-detection methods were less accurate than the spectral methods, but suggest the possibility of acquiring beat by beat data; the spectral algorithms measured heart rate to within + or -10% for the ten subjects chosen. Non-contact measurement of heart rate will be useful in chronic disease monitoring for conditions such as heart failure and cardiovascular disease.

Opportunistic mammography screening provides effective detection rates in a limited resource healthcare system.

PubMed

Teh, Yew-Ching; Tan, Gie-Hooi; Taib, Nur Aishah; Rahmat, Kartini; Westerhout, Caroline Judy; Fadzli, Farhana; See, Mee-Hoong; Jamaris, Suniza; Yip, Cheng-Har

2015-05-15

Breast cancer is the leading cause of cancer deaths in women world-wide. In low and middle income countries, where there are no population-based mammographic screening programmes, late presentation is common, and because of inadequate access to optimal treatment, survival rates are poor. Mammographic screening is well-studied in high-income countries in western populations, and because it has been shown to reduce breast cancer mortality, it has become part of the healthcare systems in such countries. However the performance of mammographic screening in a developing country is largely unknown. This study aims to evaluate the performance of mammographic screening in Malaysia, a middle income country, and to compare the stage and surgical treatment of screen-detected and symptomatic breast cancer. A retrospective review of 2510 mammograms performed from Jan to Dec 2010 in a tertiary medical centre is carried out. The three groups identified are the routine (opportunistic) screening group, the targeted (high risk) screening group and the diagnostic group. The performance indicators of each group is calculated, and stage at presentation and treatment between the screening and diagnostic group is analyzed. The cancer detection rate in the opportunistic screening group, targeted screening group, and the symptomatic group is 0.5 %, 1.25 % and 26 % respectively. The proportion of ductal carcinoma in situ is 23.1 % in the two screening groups compared to only 2.5 % in the diagnostic group. Among the opportunistic screening group, the cancer detection rate was 0.2 % in women below 50 years old compared to 0.65 % in women 50 years and above. The performance indicators are within international standards. Early-staged breast cancer (Stage 0-2) were 84.6 % in the screening groups compared to 61.1 % in the diagnostic group. From the results, in a setting with resource constraints, targeted screening of high risk individuals will give a higher yield, and if more resources are available, population-based screening of women 50 and above is effective. Opportunistic mammographic screening is feasible and effective in a middle income country with performance indicators within international standards. Waiting until women are symptomatic will lead to more advanced cancers.

Comparing scat detection dogs, cameras, and hair snares for surveying carnivores

USGS Publications Warehouse

Long, Robert A.; Donovan, T.M.; MacKay, Paula; Zielinski, William J.; Buzas, Jeffrey S.

2007-01-01

Carnivores typically require large areas of habitat, exist at low natural densities, and exhibit elusive behavior - characteristics that render them difficult to study. Noninvasive survey methods increasingly provide means to collect extensive data on carnivore occupancy, distribution, and abundance. During the summers of 2003-2004, we compared the abilities of scat detection dogs, remote cameras, and hair snares to detect black bears (Ursus americanus), fishers (Martes pennanti), and bobcats (Lynx rufus) at 168 sites throughout Vermont. All 3 methods detected black bears; neither fishers nor bobcats were detected by hair snares. Scat detection dogs yielded the highest raw detection rate and probability of detection (given presence) for each of the target species, as well as the greatest number of unique detections (i.e., occasions when only one method detected the target species). We estimated that the mean probability of detecting the target species during a single visit to a site with a detection dog was 0.87 for black bears, 0.84 for fishers, and 0.27 for bobcats. Although the cost of surveying with detection dogs was higher than that of remote cameras or hair snares, the efficiency of this method rendered it the most cost-effective survey method.

Comparative analysis of methods for detecting interacting loci

PubMed Central

2011-01-01

Background Interactions among genetic loci are believed to play an important role in disease risk. While many methods have been proposed for detecting such interactions, their relative performance remains largely unclear, mainly because different data sources, detection performance criteria, and experimental protocols were used in the papers introducing these methods and in subsequent studies. Moreover, there have been very few studies strictly focused on comparison of existing methods. Given the importance of detecting gene-gene and gene-environment interactions, a rigorous, comprehensive comparison of performance and limitations of available interaction detection methods is warranted. Results We report a comparison of eight representative methods, of which seven were specifically designed to detect interactions among single nucleotide polymorphisms (SNPs), with the last a popular main-effect testing method used as a baseline for performance evaluation. The selected methods, multifactor dimensionality reduction (MDR), full interaction model (FIM), information gain (IG), Bayesian epistasis association mapping (BEAM), SNP harvester (SH), maximum entropy conditional probability modeling (MECPM), logistic regression with an interaction term (LRIT), and logistic regression (LR) were compared on a large number of simulated data sets, each, consistent with complex disease models, embedding multiple sets of interacting SNPs, under different interaction models. The assessment criteria included several relevant detection power measures, family-wise type I error rate, and computational complexity. There are several important results from this study. First, while some SNPs in interactions with strong effects are successfully detected, most of the methods miss many interacting SNPs at an acceptable rate of false positives. In this study, the best-performing method was MECPM. Second, the statistical significance assessment criteria, used by some of the methods to control the type I error rate, are quite conservative, thereby limiting their power and making it difficult to fairly compare them. Third, as expected, power varies for different models and as a function of penetrance, minor allele frequency, linkage disequilibrium and marginal effects. Fourth, the analytical relationships between power and these factors are derived, aiding in the interpretation of the study results. Fifth, for these methods the magnitude of the main effect influences the power of the tests. Sixth, most methods can detect some ground-truth SNPs but have modest power to detect the whole set of interacting SNPs. Conclusion This comparison study provides new insights into the strengths and limitations of current methods for detecting interacting loci. This study, along with freely available simulation tools we provide, should help support development of improved methods. The simulation tools are available at: http://code.google.com/p/simulation-tool-bmc-ms9169818735220977/downloads/list. PMID:21729295

Comparative analysis of methods for detecting interacting loci.

PubMed

Chen, Li; Yu, Guoqiang; Langefeld, Carl D; Miller, David J; Guy, Richard T; Raghuram, Jayaram; Yuan, Xiguo; Herrington, David M; Wang, Yue

2011-07-05

Interactions among genetic loci are believed to play an important role in disease risk. While many methods have been proposed for detecting such interactions, their relative performance remains largely unclear, mainly because different data sources, detection performance criteria, and experimental protocols were used in the papers introducing these methods and in subsequent studies. Moreover, there have been very few studies strictly focused on comparison of existing methods. Given the importance of detecting gene-gene and gene-environment interactions, a rigorous, comprehensive comparison of performance and limitations of available interaction detection methods is warranted. We report a comparison of eight representative methods, of which seven were specifically designed to detect interactions among single nucleotide polymorphisms (SNPs), with the last a popular main-effect testing method used as a baseline for performance evaluation. The selected methods, multifactor dimensionality reduction (MDR), full interaction model (FIM), information gain (IG), Bayesian epistasis association mapping (BEAM), SNP harvester (SH), maximum entropy conditional probability modeling (MECPM), logistic regression with an interaction term (LRIT), and logistic regression (LR) were compared on a large number of simulated data sets, each, consistent with complex disease models, embedding multiple sets of interacting SNPs, under different interaction models. The assessment criteria included several relevant detection power measures, family-wise type I error rate, and computational complexity. There are several important results from this study. First, while some SNPs in interactions with strong effects are successfully detected, most of the methods miss many interacting SNPs at an acceptable rate of false positives. In this study, the best-performing method was MECPM. Second, the statistical significance assessment criteria, used by some of the methods to control the type I error rate, are quite conservative, thereby limiting their power and making it difficult to fairly compare them. Third, as expected, power varies for different models and as a function of penetrance, minor allele frequency, linkage disequilibrium and marginal effects. Fourth, the analytical relationships between power and these factors are derived, aiding in the interpretation of the study results. Fifth, for these methods the magnitude of the main effect influences the power of the tests. Sixth, most methods can detect some ground-truth SNPs but have modest power to detect the whole set of interacting SNPs. This comparison study provides new insights into the strengths and limitations of current methods for detecting interacting loci. This study, along with freely available simulation tools we provide, should help support development of improved methods. The simulation tools are available at: http://code.google.com/p/simulation-tool-bmc-ms9169818735220977/downloads/list.

Comparison of human observer and algorithmic target detection in nonurban forward-looking infrared imagery

NASA Astrophysics Data System (ADS)

Weber, Bruce A.

2005-07-01

We have performed an experiment that compares the performance of human observers with that of a robust algorithm for the detection of targets in difficult, nonurban forward-looking infrared imagery. Our purpose was to benchmark the comparison and document performance differences for future algorithm improvement. The scale-insensitive detection algorithm, used as a benchmark by the Night Vision Electronic Sensors Directorate for algorithm evaluation, employed a combination of contrastlike features to locate targets. Detection receiver operating characteristic curves and observer-confidence analyses were used to compare human and algorithmic responses and to gain insight into differences. The test database contained ground targets, in natural clutter, whose detectability, as judged by human observers, ranged from easy to very difficult. In general, as compared with human observers, the algorithm detected most of the same targets, but correlated confidence with correct detections poorly and produced many more false alarms at any useful level of performance. Though characterizing human performance was not the intent of this study, results suggest that previous observational experience was not a strong predictor of human performance, and that combining individual human observations by majority vote significantly reduced false-alarm rates.

Fusion of KLMS and blob based pre-screener for buried landmine detection using ground penetrating radar

NASA Astrophysics Data System (ADS)

Baydar, Bora; Akar, Gözde Bozdaǧi.; Yüksel, Seniha E.; Öztürk, Serhat

2016-05-01

In this paper, a decision level fusion using multiple pre-screener algorithms is proposed for the detection of buried landmines from Ground Penetrating Radar (GPR) data. The Kernel Least Mean Square (KLMS) and the Blob Filter pre-screeners are fused together to work in real time with less false alarms and higher true detection rates. The effect of the kernel variance is investigated for the KLMS algorithm. Also, the results of the KLMS and KLMS+Blob filter algorithms are compared to the LMS method in terms of processing time and false alarm rates. Proposed algorithm is tested on both simulated data and real data collected at the field of IPA Defence at METU, Ankara, Turkey.

[Molecular beacon based PNA-FISH method combined with fluorescence scanning for rapid detection of Listeria monocytogenes].

PubMed

Wu, Shan; Zhang, Xiaofeng; Shuai, Jiangbing; Li, Ke; Yu, Huizhen; Jin, Chenchen

2016-07-04

To simplify the PNA-FISH (Peptide nucleic acid-fluorescence in situ hybridization) test, molecular beacon based PNA probe combined with fluorescence scanning detection technology was applied to replace the original microscope observation to detect Listeria monocytogenes The 5′ end and 3′ end of the L. monocytogenes specific PNA probes were labeled with the fluorescent group and the quenching group respectively, to form a molecular beacon based PNA probe. When PNA probe used for fluorescence scanning and N1 treatment as the control, the false positive rate was 11.4%, and the false negative rate was 0; when N2 treatment as the control, the false positive rate decreased to 4.3%, but the false negative rate rose to 18.6%. When beacon based PNA probe used for fluorescence scanning, taken N1 treatment as blank control, the false positive rate was 8.6%, and the false negative rate was 1.4%; taken N2 treatment as blank control, the false positive rate was 5.7%, and the false negative rate was 1.4%. Compared with PNA probe, molecular beacon based PNA probe can effectively reduce false positives and false negatives. The success rates of hybridization of the two PNA probes were 83.3% and 95.2% respectively; and the rates of the two beacon based PNA probes were 91.7% and 90.5% respectively, which indicated that labeling the both ends of the PNA probe dose not decrease the hybridization rate with the target bacteria. The combination of liquid phase PNA-FISH and fluorescence scanning method, can significantly improve the detection efficiency.

Comparison of Glaucoma Progression Detection by Optical Coherence Tomography and Visual Field.

PubMed

Zhang, Xinbo; Dastiridou, Anna; Francis, Brian A; Tan, Ou; Varma, Rohit; Greenfield, David S; Schuman, Joel S; Huang, David

2017-12-01

To compare longitudinal glaucoma progression detection using optical coherence tomography (OCT) and visual field (VF). Validity assessment. We analyzed subjects with more than 4 semi-annual follow-up visits (every 6 months) in the multicenter Advanced Imaging for Glaucoma Study. Fourier-domain optical coherence tomography (OCT) was used to map the thickness of the peripapillary retinal nerve fiber layer (NFL) and ganglion cell complex (GCC). OCT-based progression detection was defined as a significant negative trend for either NFL or GCC. VF progression was reached if either the event or trend analysis reached significance. The analysis included 356 glaucoma suspect/preperimetric glaucoma (GS/PPG) eyes and 153 perimetric glaucoma (PG) eyes. Follow-up length was 54.1 ± 16.2 months for GS/PPG eyes and 56.7 ± 16.0 for PG eyes. Progression was detected in 62.1% of PG eyes and 59.8% of GS/PPG eyes by OCT, significantly (P < .001) more than the detection rate of 41.8% and 27.3% by VF. In severity-stratified analysis of PG eyes, OCT had significantly higher detection rate than VF in mild PG (63.1% vs. 38.7%, P < .001), but not in moderate and advanced PG. The rate of NFL thinning slowed dramatically in advanced PG, but GCC thinning rate remained relatively steady and allowed good progression detection even in advanced disease. The Kaplan-Meier time-to-event analyses showed that OCT detected progression earlier than VF in both PG and GS/PPG groups. OCT is more sensitive than VF for the detection of progression in early glaucoma. While the utility of NFL declines in advanced glaucoma, GCC remains a sensitive progression detector from early to advanced stages. Copyright © 2017 Elsevier Inc. All rights reserved.

Comparison of droplet digital PCR and conventional quantitative PCR for measuring EGFR gene mutation

PubMed Central

ZHANG, BO; XU, CHUN-WEI; SHAO, YUN; WANG, HUAI-TAO; WU, YONG-FANG; SONG, YE-YING; LI, XIAO-BING; ZHANG, ZHE; WANG, WEN-JING; LI, LI-QIONG; CAI, CONG-LI

2015-01-01

Early detection of epidermal growth factor receptor (EGFR) mutation, particularly EGFR T790M mutation, is of clinical significance. The aim of the present study was to compare the performances of amplification refractory mutation system-based quantitative polymerase chain reaction (ARMS-qPCR) and droplet digital polymerase chain reaction (ddPCR) approaches in the detection of EGFR mutation and explore the feasibility of using ddPCR in the detection of samples with low mutation rates. EGFR gene mutations in plasmid samples with different T790M mutation rates (0.1–5%) and 10 clinical samples were detected using the ARMS-qPCR and ddPCR approaches. The results demonstrated that the ARMS-qPCR method stably detected the plasmid samples (6,000 copies) with 5 and 1% mutation rates, while the ddPCR approach reliably detected those with 5% (398 copies), 1% (57 copies), 0.5% (24 copies) and 0.1% (average 6 copies) mutation rates. For the 10 clinical samples, the results for nine samples by the ARMS-qPCR and ddPCR methods were consistent; however, the sample N006, indicated to be EGFR wild-type by ARMS-qPCR, was revealed to have a clear EGFR T790M mutation with seven copies of mutant alleles in a background of 6,000 wild-type copies using ddPCR technology. This study demonstrates the feasibility of applying the ddPCR system to detect EGFR mutation and identified the advantage of ddPCR in the detection of samples with a low EGFR mutation abundance, particularly the secondary EGFR T790M resistance mutation, which enables early diagnosis before acquired resistance to tyrosine kinase inhibitors becomes clinically detectable. PMID:25780439

Algorithm and assessment work of active fire detection based on FengYun-3C/VIRR

NASA Astrophysics Data System (ADS)

Lin, Z.; Chen, F.

2017-12-01

The wildfire is one of the most destructive and uncontrollable disasters and causes huge environmental, ecological, social effects. To better serve scientific research and practical fire management, an algorithm and corresponding validation work of active fire detection based on FengYun-3C/VIRR data, which is an optical sensor onboard the Chinese polar-orbiting meteorological sun-synchronous satellite, is hereby introduced. While the main structure heritages the `contextual algorithm', some new concepts including `infrared channel slope' are introduced for better adaptions to different situations. The validation work contains three parts: 1) comparing with the current FengYun-3C fire product GFR; 2) comparing with MODIS fire products; 3) comparing with Landsat series data. Study areas are selected from different places all over the world from 2014 to 2016. The results showed great improvement on GFR files on accuracy of both positioning and detection rate. In most study areas, the results match well with MODIS products and Landsat series data (with over 85% match degree) despite the differences in imaging time. However, detection rates and match degrees in Africa and South-east Asia are not satisfied (around 70%), where the occurrences of numerous small fire events and corresponding smokes may strongly affect the results of the algorithm. This is our future research direction and one of the main improvements requires achieving.

Hough transform for clustered microcalcifications detection in full-field digital mammograms

NASA Astrophysics Data System (ADS)

Fanizzi, A.; Basile, T. M. A.; Losurdo, L.; Amoroso, N.; Bellotti, R.; Bottigli, U.; Dentamaro, R.; Didonna, V.; Fausto, A.; Massafra, R.; Moschetta, M.; Tamborra, P.; Tangaro, S.; La Forgia, D.

2017-09-01

Many screening programs use mammography as principal diagnostic tool for detecting breast cancer at a very early stage. Despite the efficacy of the mammograms in highlighting breast diseases, the detection of some lesions is still doubtless for radiologists. In particular, the extremely minute and elongated salt-like particles of microcalcifications are sometimes no larger than 0.1 mm and represent approximately half of all cancer detected by means of mammograms. Hence the need for automatic tools able to support radiologists in their work. Here, we propose a computer assisted diagnostic tool to support radiologists in identifying microcalcifications in full (native) digital mammographic images. The proposed CAD system consists of a pre-processing step, that improves contrast and reduces noise by applying Sobel edge detection algorithm and Gaussian filter, followed by a microcalcification detection step performed by exploiting the circular Hough transform. The procedure performance was tested on 200 images coming from the Breast Cancer Digital Repository (BCDR), a publicly available database. The automatically detected clusters of microcalcifications were evaluated by skilled radiologists which asses the validity of the correctly identified regions of interest as well as the system error in case of missed clustered microcalcifications. The system performance was evaluated in terms of Sensitivity and False Positives per images (FPi) rate resulting comparable to the state-of-art approaches. The proposed model was able to accurately predict the microcalcification clusters obtaining performances (sensibility = 91.78% and FPi rate = 3.99) which favorably compare to other state-of-the-art approaches.

Comparison of digital tomosynthesis and chest radiography for the detection of pulmonary nodules: systematic review and meta-analysis

PubMed Central

Kim, Jun H; Lee, Kyung H; Kim, Kyoung-Tae; Ahn, Hyeong S; Kim, Yeo J; Lee, Ha Y; Jeon, Yong S

2016-01-01

Objective: To compare the diagnostic accuracy of digital tomosynthesis (DTS) with that of chest radiography for the detection of pulmonary nodules by meta-analysis. Methods: A systematic literature search was performed to identify relevant original studies from 1 January 1 1976 to 31 August 31 2016. The quality of included studies was assessed by quality assessment of diagnostic accuracy studies-2. Per-patient data were used to calculate the sensitivity and specificity and per-lesion data were used to calculate the detection rate. Summary receiver-operating characteristic curves were drawn for pulmonary nodule detection. Results: 16 studies met the inclusion criteria. 1017 patients on a per-patient basis and 2159 lesions on a per-lesion basis from 16 eligible studies were evaluated. The pooled patient-based sensitivity of DTS was 0.85 [95% confidence interval (CI) 0.83–0.88] and the specificity was 0.95 (0.93–0.96). The pooled sensitivity and specificity of chest radiography were 0.47 (0.44–0.51) and 0.37 (0.34–0.40), respectively. The per-lesion detection rate was 2.90 (95% CI 2.63–3.19). Conclusion: DTS has higher diagnostic accuracy than chest radiography for detection of pulmonary nodules. Chest radiography has low sensitivity but similar specificity, comparable with that of DTS. Advances in knowledge: DTS has higher diagnostic accuracy than chest radiography for the detection of pulmonary nodules. PMID:27759428

Comparison of automated processing of flocked swabs with manual processing of fiber swabs for detection of nasal carriage of Staphylococcus aureus.

PubMed

Jones, Gillian; Matthews, Roger; Cunningham, Richard; Jenks, Peter

2011-07-01

The sensitivity of automated culture of Staphylococcus aureus from flocked swabs versus that of manual culture of fiber swabs was prospectively compared using nasal swabs from 867 patients. Automated culture from flocked swabs significantly increased the detection rate, by 13.1% for direct culture and 10.2% for enrichment culture.

Performance and cost analysis of Siriraj liquid-based cytology: a direct-to-vial study.

PubMed

Laiwejpithaya, Somsak; Benjapibal, Mongkol; Laiwejpithaya, Sujera; Wongtiraporn, Weerasak; Sangkarat, Suthi; Rattanachaiyanont, Manee

2009-12-01

To compare the cytological diagnoses, specimen adequacy, and cost of the Siriraj liquid-based cytology (LBC) with those of the conventional smear technique. An observational study with historical comparison was conducted in a tertiary university hospital. Cytological reports of 23,676 Siriraj-LBC specimens obtained in 2006 were compared with those of 25,510 conventional smears obtained in 2004. Overall prevalence of abnormal cervical cytology detected by conventional smear was 1.76% and by Siriraj-LBC was 3.70%. Compared with the conventional method, the Siriraj-LBC yielded a significantly higher overall detection rate of abnormal cervical cytology, with a 110.23% increase in the detection rate (P<0.001), mainly due to the increase in diagnosis of squamous intraepithelial lesions (SIL), both low and high grade, together with atypical squamous cells of undetermined significance, "atypical squamous cells cannot exclude HSIL", and malignancies, but not atypical glandular cells. The Siriraj-LBC had a smaller proportion of unsatisfactory slides (4.94% vs. 18.60%, P<0.001) and a higher negative predictive value (96.33% vs. 92.74%, P=0.001), but no difference in positive predictive value (83.03% vs. 86.83%, P=0.285). The cost of Siriraj-LBC was approximately 67% higher than that of the conventional cytology used in Siriraj Hospital and 50-70% lower than that of the commercially available LBC techniques in Thailand. The Siriraj-LBC increases the detection rate of abnormal cytology, improves specimen adequacy, and enhances the negative predictive value without compromising the positive predictive value. For centers where conventional Pap smear does not perform well, the introduction of a low cost Siriraj-LBC might help to improve performance and it may be an economical alternative to the commercially available liquid-based cytology.

Differences in detection rates of adenomas and serrated polyps in screening versus surveillance colonoscopies, based on the new hampshire colonoscopy registry.

PubMed

Anderson, Joseph C; Butterly, Lynn F; Goodrich, Martha; Robinson, Christina M; Weiss, Julia E

2013-10-01

The adenoma detection rate (ADR) is an important quality indicator originally developed for screening colonoscopies. However, it is unclear whether the ADR should be calculated using data from screening and surveillance examinations. The recommended benchmark ADR for screening examinations is 20% (15% for women and 25% for men ≥50 y). There are few data available to compare ADRs from surveillance vs screening colonoscopies. We used a population-based registry to compare ADRs from screening vs surveillance colonoscopies. The serrated polyp detection rate (SDR), a potential new quality indicator, also was examined. By using data from the statewide New Hampshire Colonoscopy Registry, we excluded incomplete and diagnostic colonoscopies, and those performed in patients with inflammatory bowel disease, familial syndromes, or poor bowel preparation. We calculated the ADR and SDR (number of colonoscopies with at least 1 adenoma or serrated polyp detected, respectively, divided by the number of colonoscopies) from 9100 colonoscopies. The ADR and SDR were compared by colonoscopy indication (screening, surveillance), age at colonoscopy (50-64 y, ≥65 y), and sex. The ADR was significantly higher in surveillance colonoscopies (37%) than screening colonoscopies (25%; P < .001). This difference was observed for both sexes and age groups. There was a smaller difference in the SDR of screening (8%) vs surveillance colonoscopies (10%; P < .001). In a population-based study, we found that addition of data from surveillance colonoscopies increased the ADR but had a smaller effect on the SDR. These findings indicate that when calculating ADR as a quality measure, endoscopists should use screening, rather than surveillance colonoscopy, data. Copyright © 2013 AGA Institute. Published by Elsevier Inc. All rights reserved.

Differences in Detection Rates of Adenomas and Serrated Polyps in Screening Versus Surveillance Colonoscopies, Based on the New Hampshire Colonoscopy Registry

PubMed Central

ANDERSON, JOSEPH C.; BUTTERLY, LYNN; GOODRICH, MARTHA; ROBINSON, CHRISTINA M.; WEISS, JULIA E.

2013-01-01

BACKGROUND & AIMS The adenoma detection rate (ADR) is an important quality indicator originally developed for screening colonoscopies. However, it is unclear whether the ADR should be calculated using data from screening and surveillance examinations. The recommended benchmark ADR for screening examinations is 20% (15% for women and 25% for men ≥ 50 y). There are few data available to compare ADRs from surveillance vs screening colonoscopies. We used a population-based registry to compare ADRs from screening vs surveillance colonoscopies. The serrated polyp detection rate (SDR), a potential new quality indicator, also was examined. METHODS By using data from the statewide New Hampshire Colonoscopy Registry, we excluded incomplete and diagnostic colonoscopies, and those performed in patients with inflammatory bowel disease, familial syndromes, or poor bowel preparation. We calculated the ADR and SDR (number of colonoscopies with at least 1 adenoma or serrated polyp detected, respectively, divided by the number of colonoscopies) from 9100 colonoscopies. The ADR and SDR were compared by colonoscopy indication (screening, surveillance), age at colonoscopy (50–64 y, ≥65 y), and sex. RESULTS The ADR was significantly higher in surveillance colonoscopies (37%) than screening colonoscopies (25%; P < .001). This difference was observed for both sexes and age groups. There was a smaller difference in the SDR of screening (8%) vs surveillance colonoscopies (10%; P < .001). CONCLUSIONS In a population-based study, we found that addition of data from surveillance colonoscopies increased the ADR, but had a smaller effect on the SDR. These findings indicate that when calculating ADR as a quality measure, endoscopists should use screening, rather than surveillance colonoscopy, data. PMID:23660415

Using risk-tracing snowball approach to increase HIV case detection among high-risk populations in Cambodia: an intervention study.

PubMed

Chhim, Srean; Macom, John; Pav, Chettana; Nim, Nirada; Yun, Phearun; Seng, Sopheap; Chhim, Kolab; Tuot, Sovannary; Yi, Siyan

2017-10-18

Early HIV diagnosis and initiation onto antiretroviral therapy may prevent ongoing spread of HIV. Risk Tracing Snowball Approach (RTSA) has been shown to be effective in detecting new HIV cases in other settings. The main objective of this study is to evaluate the effectiveness of RTSA in increasing the rate of newly identified HIV cases among high-risk populations. Our second objective was to evaluate the effectiveness of RTSA, as compared to the walk-in group, in increasing the number of HIV tests and early case detection. This study was conducted from April 1 to September 30, 2016 at two NGO clinics in Phnom Penh, Cambodia. Respondent driven sampling method was adapted to develop RTSA to reach high-risk populations, including key populations and the general population who have social connections with key populations. Bivariate and multivariate logistic regression analyses were conducted. During the implementation period, 721 clients walked in for HIV testing (walk-in group), and all were invited to be seeds. Of the invited clients, 36.6% agreed to serve as seeds. Throughout the implementation, 6195 coupons were distributed to seeds or recruiters, and resulted in 1572 clients visiting the two clinics with coupons (RTSA group), for a coupon return rate of 25.3%. The rate of newly identified HIV cases among the RTSA group was significantly lower compared to that in walk-in group. However, the highest number of newly identified HIV cases was found during the implementation period, compared to both pre- and post-implementation period. Although statistically not significant, the mean CD4 count of newly identified HIV cases detected through RTSA was almost 200 cells/mm3 higher than that in the walk-in group. Although the rate of newly identified HIV cases among the RTSA group was lower than that in the walk-in group, the inclusion of RTSA in addition to the traditional walk-in method boosted new HIV case detection in the two participating clinics. A higher mean CD4 count for the RTSA group may reveal that RTSA may be able to detect HIV cases earlier than the traditional walk-in approach. Further research is needed to understand whether RTSA is a cost-effective intervention to prevent ongoing spread of the HIV among high-risk populations in Cambodia.

Diagnostic accuracy of prostate health index to identify aggressive prostate cancer. An Institutional validation study.

PubMed

Morote, J; Celma, A; Planas, J; Placer, J; Ferrer, R; de Torres, I; Pacciuci, R; Olivan, M

2016-01-01

New generations of tumor markers used to detect prostate cancer (PCa) should be able to discriminate men with aggressive PCa of those without PCa or nonaggressive tumors. The objective of this study has been to validate Prostate Health Index (PHI) as a marker of aggressive PCa in one academic institution. PHI was assessed in 357 men scheduled to prostatic biopsy between June of 2013 and July 2014 in one academic institution. Thereafter a subset of 183 men younger than 75 years and total PSA (tPSA) between 3.0 and 10.0 ng/mL, scheduled to it first prostatic biopsy, was retrospectively selected for this study. Twelve cores TRUS guided biopsy, under local anaesthesia, was performed in all cases. Total PSA, free PSA (fPSA), and [-2] proPSA (p2PSA) and prostate volume were determined before the procedure and %fPSA, PSA density (PSAd) and PHI were calculated. Aggressive tumors were considered if any Gleason 4 pattern was found. PHI was compared to %fPSA and PSAd through their ROC curves. Thresholds to detect 90%, 95% of all tumors and 95% and 100% of aggressive tumors were estimated and rates of unnecessary avoided biopsies were calculated and compared. The rate of PCa detection was 37.2% (68) and the rate of aggressive tumors was 24.6% (45). The PHI area under the curve was higher than those of %fPSA and PSAd to detect any PCa (0.749 vs 0.606 and 0.668 respectively) or to detect only aggressive tumors (0.786 vs 0.677 and 0.708 respectively), however, significant differences were not found. The avoided biopsy rates to detect 95% of aggressive tumors were 20.2% for PHI, 14.8% for %fPSA, and 23.5% for PSAd. Even more, to detect all aggressive tumors these rates dropped to 4.9% for PHI, 9.3% for %fPSA, and 7.9% for PSAd. PHI seems a good marker to PCa diagnosis. However, PHI was not superior to %fPSA and PSAd to identify at least 95% of aggressive tumors. Copyright © 2016 AEU. Publicado por Elsevier España, S.L.U. All rights reserved.

Automated Nucleic Acid Extraction Systems for Detecting Cytomegalovirus and Epstein-Barr Virus Using Real-Time PCR: A Comparison Study Between the QIAsymphony RGQ and QIAcube Systems.

PubMed

Kim, Hanah; Hur, Mina; Kim, Ji Young; Moon, Hee Won; Yun, Yeo Min; Cho, Hyun Chan

2017-03-01

Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) are increasingly important in immunocompromised patients. Nucleic acid extraction methods could affect the results of viral nucleic acid amplification tests. We compared two automated nucleic acid extraction systems for detecting CMV and EBV using real-time PCR assays. One hundred and fifty-three whole blood (WB) samples were tested for CMV detection, and 117 WB samples were tested for EBV detection. Viral nucleic acid was extracted in parallel by using QIAsymphony RGQ and QIAcube (Qiagen GmbH, Germany), and real-time PCR assays for CMV and EBV were performed with a Rotor-Gene Q real-time PCR cycler (Qiagen). Detection rates for CMV and EBV were compared, and agreements between the two systems were analyzed. The detection rate of CMV and EBV differed significantly between the QIAsymphony RGQ and QIAcube systems (CMV, 59.5% [91/153] vs 43.8% [67/153], P=0.0005; EBV, 59.0% [69/117] vs 42.7% [50/117], P=0.0008). The two systems showed moderate agreement for CMV and EBV detection (kappa=0.43 and 0.52, respectively). QIAsymphony RGQ showed a negligible correlation with QIAcube for quantitative EBV detection. QIAcube exhibited EBV PCR inhibition in 23.9% (28/117) of samples. Automated nucleic acid extraction systems have different performances and significantly affect the detection of viral pathogens. The QIAsymphony RGQ system appears to be superior to the QIAcube system for detecting CMV and EBV. A suitable sample preparation system should be considered for optimized nucleic acid amplification in clinical laboratories.

Two stage algorithm vs commonly used approaches for the suspect screening of complex environmental samples analyzed via liquid chromatography high resolution time of flight mass spectroscopy: A test study.

PubMed

Samanipour, Saer; Baz-Lomba, Jose A; Alygizakis, Nikiforos A; Reid, Malcolm J; Thomaidis, Nikolaos S; Thomas, Kevin V

2017-06-09

LC-HR-QTOF-MS recently has become a commonly used approach for the analysis of complex samples. However, identification of small organic molecules in complex samples with the highest level of confidence is a challenging task. Here we report on the implementation of a two stage algorithm for LC-HR-QTOF-MS datasets. We compared the performances of the two stage algorithm, implemented via NIVA_MZ_Analyzer™, with two commonly used approaches (i.e. feature detection and XIC peak picking, implemented via UNIFI by Waters and TASQ by Bruker, respectively) for the suspect analysis of four influent wastewater samples. We first evaluated the cross platform compatibility of LC-HR-QTOF-MS datasets generated via instruments from two different manufacturers (i.e. Waters and Bruker). Our data showed that with an appropriate spectral weighting function the spectra recorded by the two tested instruments are comparable for our analytes. As a consequence, we were able to perform full spectral comparison between the data generated via the two studied instruments. Four extracts of wastewater influent were analyzed for 89 analytes, thus 356 detection cases. The analytes were divided into 158 detection cases of artificial suspect analytes (i.e. verified by target analysis) and 198 true suspects. The two stage algorithm resulted in a zero rate of false positive detection, based on the artificial suspect analytes while producing a rate of false negative detection of 0.12. For the conventional approaches, the rates of false positive detection varied between 0.06 for UNIFI and 0.15 for TASQ. The rates of false negative detection for these methods ranged between 0.07 for TASQ and 0.09 for UNIFI. The effect of background signal complexity on the two stage algorithm was evaluated through the generation of a synthetic signal. We further discuss the boundaries of applicability of the two stage algorithm. The importance of background knowledge and experience in evaluating the reliability of results during the suspect screening was evaluated. Copyright © 2017 Elsevier B.V. All rights reserved.

[Analysis on occupational health surveillance to workers exposed to toxic environment in a city].

PubMed

Wang, X; Li, M L; Tang, H J; Zeng, Q

2017-12-20

Objective: To understand the status of occupational health surveillance to workers exposed to toxic environment in a city, so as to provide scientific basis for strategy of occupational diseases prevention. Methods: In January 2017, collecting the data of on-the-job poisonous and harmful workers occupational health surveillance in the city from January 1, 2010 to December 31, 2016 in China Information System for Disease Control and Prevention, the trend of occupational health monitoring in the city was analyzed, and the differences between diverseeconomic types, enterprise scale, industry nature and hazard factors were analyzed and compared. Results: The occupational health examination rate showed an overall upward trend in workers exposed to dust in the city from 2010-2016 ( t =3.607, P <0.05) , and the detection rate of occupational contraindications was on the rise in workers exposed to chemical factors ( t =3.071, P <0.05). The detection rate of occupational contraindications and suspected occupational diseaseswere significant in different economic types, enterprise scale, industry nature and hazard factors ( P <0.05). The detection rate of occupational contraindications was the highest among the large enterprises (1.24%) , the manufacturing industry (0.84%) and the state-owned economy (1.49%). The detection rate of suspected occupational diseases (0.04%) and occupational contraindications (1.15%) were the highest in the physical factors. Conclusion: Occupational health monitoring in the city is not optimistic. It is necessary to focuson the occupational health care of manufacturing practitioners, raise the detection rate of suspected occupational diseases, and standard the occupational health check work to protect the occupational health.

Aphids preserved in propylene glycol can be used for reverse transcription-polymerase chain reaction detection of Potato virus Y.

PubMed

Nie, Xianzhou; Pelletier, Yvan; Mason, Nicola; Dilworth, Andrea; Giguère, Marie-Andrée

2011-08-01

The effectiveness of propylene glycol on the retention of RNA target of Potato virus Y (PVY), an aphid stylet-borne virus, in Myzus persicae was investigated in comparison to ethanol and liquid nitrogen/-80°C. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the PVY targets from the propylene glycol/ethanol/liquid nitrogen preserved single aphids after a 5min acquisition period from infected potato plants. In the liquid nitrogen/-80°C and 70% ethanol treatments, 55.6% and 38.8% aphids tested PVY-positive, respectively. In the 0-75% propylene glycol treatments, 12.2-44.7% aphids tested PVY-positive. The lowest detection rate was in the 0% (positive rate, 15.2%) and the 10% propylene glycol (positive rate, 12.2%). As the propylene glycol concentration increased to 25%, 29.8% aphids tested positive. A high PVY-positive rate was also found in 35-75% propylene glycol treatments at 44.7% (35% propylene glycol), 36.7% (50% propylene glycol) and 34.8% (75% propylene glycol), which is comparable to the rate shown in 70% ethanol. No significant difference in the positive detection rate was observed in aphids preserved in 50% propylene glycol at room temperature for 2, 4 and 10 days. These results demonstrate that propylene glycol at 25-75% can retain PVY targets effectively in aphids for an extended time period, and thus can be used in aphid traps to preserve viruliferous aphids for later RT-PCR detection of PVY. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

Capnography and chest wall impedance algorithms for ventilation detection during cardiopulmonary resuscitation

PubMed Central

Edelson, Dana P.; Eilevstjønn, Joar; Weidman, Elizabeth K.; Retzer, Elizabeth; Vanden Hoek, Terry L.; Abella, Benjamin S.

2009-01-01

Objective Hyperventilation is both common and detrimental during cardiopulmonary resuscitation (CPR). Chest wall impedance algorithms have been developed to detect ventilations during CPR. However, impedance signals are challenged by noise artifact from multiple sources, including chest compressions. Capnography has been proposed as an alternate method to measure ventilations. We sought to assess and compare the adequacy of these two approaches. Methods Continuous chest wall impedance and capnography were recorded during consecutive in-hospital cardiac arrests. Algorithms utilizing each of these data sources were compared to a manually determined “gold standard” reference ventilation rate. In addition, a combination algorithm, which utilized the highest of the impedance or capnography values in any given minute, was similarly evaluated. Results Data were collected from 37 cardiac arrests, yielding 438 min of data with continuous chest compressions and concurrent recording of impedance and capnography. The manually calculated mean ventilation rate was 13.3±4.3/min. In comparison, the defibrillator’s impedance-based algorithm yielded an average rate of 11.3±4.4/min (p=0.0001) while the capnography rate was 11.7±3.7/min (p=0.0009). There was no significant difference in sensitivity and positive predictive value between the two methods. The combination algorithm rate was 12.4±3.5/min (p=0.02), which yielded the highest fraction of minutes with respiratory rates within 2/min of the reference. The impedance signal was uninterpretable 19.5% of the time, compared with 9.7% for capnography. However, the signals were only simultaneously non-interpretable 0.8% of the time. Conclusions Both the impedance and capnography-based algorithms underestimated the ventilation rate. Reliable ventilation rate determination may require a novel combination of multiple algorithms during resuscitation. PMID:20036047

Peri-ictal ECG changes in childhood epilepsy: implications for detection systems.

PubMed

Jansen, Katrien; Varon, Carolina; Van Huffel, Sabine; Lagae, Lieven

2013-10-01

Early detection of seizures could reduce associated morbidity and mortality and improve the quality of life of patients with epilepsy. In this study, the aim was to investigate whether ictal tachycardia is present in focal and generalized epileptic seizures in children. We sought to predict in which type of seizures tachycardia can be identified before actual seizure onset. Electrocardiogram segments in 80 seizures were analyzed in time and frequency domains before and after the onset of epileptic seizures on EEG. These ECG parameters were analyzed to find the most informative ones that can be used for seizure detection. The algorithm of Leutmezer et al. was used to find the temporal relationship between the change in heart rate and seizure onset. In the time domain, the mean RR shows a significant difference before compared to after onset of the seizure in focal seizures. This can be observed in temporal lobe seizures as well as frontal lobe seizures. Calculation of mean RR interval has a high specificity for detection of ictal heart rate changes. Preictal heart rate changes are observed in 70% of the partial seizures. Ictal heart rate changes are present only in partial seizures in this childhood epilepsy study. The changes can be observed in temporal lobe seizures as well as in frontal lobe seizures. Heart rate changes precede seizure onset in 70% of the focal seizures, making seizure detection and closed-loop systems a possible therapeutic alternative in the population of children with refractory epilepsy. © 2013.

Enhancing detection of steady-state visual evoked potentials using individual training data.

PubMed

Wang, Yijun; Nakanishi, Masaki; Wang, Yu-Te; Jung, Tzyy-Ping

2014-01-01

Although the performance of steady-state visual evoked potential (SSVEP)-based brain-computer interfaces (BCIs) has improved gradually in the past decades, it still does not meet the requirement of a high communication speed in many applications. A major challenge is the interference of spontaneous background EEG activities in discriminating SSVEPs. An SSVEP BCI using frequency coding typically does not have a calibration procedure since the frequency of SSVEPs can be recognized by power spectrum density analysis (PSDA). However, the detection rate can be deteriorated by the spontaneous EEG activities within the same frequency range because phase information of SSVEPs is ignored in frequency detection. To address this problem, this study proposed to incorporate individual SSVEP training data into canonical correlation analysis (CCA) to improve the frequency detection of SSVEPs. An eight-class SSVEP dataset recorded from 10 subjects in a simulated online BCI experiment was used for performance evaluation. Compared to the standard CCA method, the proposed method obtained significantly improved detection accuracy (95.2% vs. 88.4%, p<0.05) and information transfer rates (ITR) (104.6 bits/min vs. 89.1 bits/min, p<0.05). The results suggest that the employment of individual SSVEP training data can significantly improve the detection rate and thereby facilitate the implementation of a high-speed BCI.

Detecting Recombination Hotspots from Patterns of Linkage Disequilibrium.

PubMed

Wall, Jeffrey D; Stevison, Laurie S

2016-08-09

With recent advances in DNA sequencing technologies, it has become increasingly easy to use whole-genome sequencing of unrelated individuals to assay patterns of linkage disequilibrium (LD) across the genome. One type of analysis that is commonly performed is to estimate local recombination rates and identify recombination hotspots from patterns of LD. One method for detecting recombination hotspots, LDhot, has been used in a handful of species to further our understanding of the basic biology of recombination. For the most part, the effectiveness of this method (e.g., power and false positive rate) is unknown. In this study, we run extensive simulations to compare the effectiveness of three different implementations of LDhot. We find large differences in the power and false positive rates of these different approaches, as well as a strong sensitivity to the window size used (with smaller window sizes leading to more accurate estimation of hotspot locations). We also compared our LDhot simulation results with comparable simulation results obtained from a Bayesian maximum-likelihood approach for identifying hotspots. Surprisingly, we found that the latter computationally intensive approach had substantially lower power over the parameter values considered in our simulations. Copyright © 2016 Wall and Stevison.

Detecting aseismic strain transients from seismicity data

USGS Publications Warehouse

Llenos, A.L.; McGuire, J.J.

2011-01-01

Aseismic deformation transients such as fluid flow, magma migration, and slow slip can trigger changes in seismicity rate. We present a method that can detect these seismicity rate variations and utilize these anomalies to constrain the underlying variations in stressing rate. Because ordinary aftershock sequences often obscure changes in the background seismicity caused by aseismic processes, we combine the stochastic Epidemic Type Aftershock Sequence model that describes aftershock sequences well and the physically based rate- and state-dependent friction seismicity model into a single seismicity rate model that models both aftershock activity and changes in background seismicity rate. We implement this model into a data assimilation algorithm that inverts seismicity catalogs to estimate space-time variations in stressing rate. We evaluate the method using a synthetic catalog, and then apply it to a catalog of M???1.5 events that occurred in the Salton Trough from 1990 to 2009. We validate our stressing rate estimates by comparing them to estimates from a geodetically derived slip model for a large creep event on the Obsidian Buttes fault. The results demonstrate that our approach can identify large aseismic deformation transients in a multidecade long earthquake catalog and roughly constrain the absolute magnitude of the stressing rate transients. Our method can therefore provide a way to detect aseismic transients in regions where geodetic resolution in space or time is poor. Copyright 2011 by the American Geophysical Union.

Comparing the birth rate of stellar black holes in binary black hole mergers and long gamma-ray bursts

NASA Astrophysics Data System (ADS)

Atteia, J.-L.; Dezalay, J.-P.; Godet, O.; Klotz, A.; Turpin, D.; Bernardini, M. G.

2018-02-01

Context. Gravitational wave interferometers have proven the existence of a new class of binary black hole (BBH) weighing tens of solar masses, and have provided the first reliable measurement of the rate of coalescing black holes (BHs) in the local Universe. Furthermore, long gamma-ray bursts (GRBs) detected with gamma-ray satellites are believed to be associated with the birth of stellar-mass BHs, providing a measure of the rate of these events across the history of the Universe, thanks to the measure of their cosmological redshift. These two types of sources, which are subject to different detection biases and involve BHs born in different environments with potentially different characteristics, provide complementary information on the birth rate of stellar BHs. Aim. We compare the birth rates of BHs found in BBH mergers and in long GRBs. Methods: We construct a simple model that makes reasonable assumptions on the history of GRB formation, and takes into account some major uncertainties, like the beaming angle of GRBs or the delay between the formation of BBHs and their coalescence. We use this model to evaluate the ratio of the number of stellar mass BHs formed in BBH mergers to those formed in GRBs. Results: We find that in our reference model the birth rate of stellar BHs in BBH mergers represents a significant fraction of the rate of long GRBs and that comparable birth rates are favored by models with moderate beaming angles. These numbers, however, do not consider subluminous GRBs, which may represent another population of sources associated with the birth of stellar mass BHs. We briefly discuss this result in view of our understanding of the progenitors of GRBs and BBH mergers, and we emphasize that this ratio, which will be better constrained in the coming years, can be directly compared with the prediction of stellar evolution models if a single model is used to produce GRBs and BBH mergers with the same assumptions.

[Comparison of two nucleic acid extraction methods for norovirus in oysters].

PubMed

Yuan, Qiao; Li, Hui; Deng, Xiaoling; Mo, Yanling; Fang, Ling; Ke, Changwen

2013-04-01

To explore a convenient and effective method for norovirus nucleic acid extraction from oysters suitable for long-term viral surveillance. Two methods, namely method A (glycine washing and polyethylene glycol precipitation of the virus followed by silica gel centrifugal column) and method B (protease K digestion followed by application of paramagnetic silicon) were compared for their performance in norovirus nucleic acid extraction from oysters. Real-time RT-PCR was used to detect norovirus in naturally infected oysters and in oysters with induced infection. The two methods yielded comparable positive detection rates for the samples, but the recovery rate of the virus was higher with method B than with method A. Method B is a more convenient and rapid method for norovirus nucleic acid extraction from oysters and suitable for long-term surveillance of norovirus.

Colour Doppler and microbubble contrast agent ultrasonography do not improve cancer detection rate in transrectal systematic prostate biopsy sampling.

PubMed

Taverna, Gianluigi; Morandi, Giovanni; Seveso, Mauro; Giusti, Guido; Benetti, Alessio; Colombo, Piergiuseppe; Minuti, Francesco; Grizzi, Fabio; Graziotti, Pierpaolo

2011-12-01

What's known on the subject? and What does the study add? Transrectal gray-scale ultrasonography guided prostate biopsy sampling is the method for diagnosing prostate cancer (PC) in patients with an increased prostate specific antigen level and/or abnormal digital rectal examination. Several imaging strategies have been proposed to optimize the diagnostic value of biopsy sampling, although at the first biopsy nearly 10-30% of PC still remains undiagnosed. This study compares the PC detection rate when employing Colour Doppler ultransongraphy with or without the injection of SonoVue™ microbubble contrast agent, versus the transrectal ultrasongraphy-guided systematic biopsy sampling. The limited accuracy, sensitivity, specificity and the additional cost of using the contrast agent do not justify its routine application in PC detection. • To compare prostate cancer (PC) detection rate employing colour Doppler ultrasonography with or without SonoVue™ contrast agent with transrectal ultrasonography-guided systematic biopsy sampling. • A total of 300 patients with negative digital rectal examination and transrectal grey-scale ultrasonography, with PSA values ranging between 2.5 and 9.9 ng/mL, were randomized into three groups: 100 patients (group A) underwent transrectal ultrasonography-guided systematic bioptic sampling; 100 patients (group B) underwent colour Doppler ultrasonography, and 100 patients (group C) underwent colour Doppler ultrasonography before and during the injection of SonoVue™. • Contrast-enhanced targeted biopsies were sampled into hypervascularized areas of peripheral, transitional, apical or anterior prostate zones. • All the patients included in Groups B and C underwent a further 13 systematic prostate biopsies. The cancer detection rate was calculated for each group. • In 88 (29.3%) patients a histological diagnosis of PC was made, whereas 22 (7.4%) patients were diagnosed with high-grade prostatic intraepithelial neoplasia or atypical small acinar proliferation. • No significant differences were found among the three groups for cancer detection rate (P= 0.329). • Additionally, low sensitivity, specificity and accuracy of colour Doppler with or without SonoVue™ contrast agent were found. • Prostate cancer detection rate does not significantly improve with the use of colour Doppler ultrasonography with or without SonoVue™. • Although no collateral effects have been highlighted, the combined use of colour Doppler ultrasonography and SonoVue™ determines adjunctive costs and increases the mean time for taking a single prostate biopsy. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

On Adaptive Cell-Averaging CFAR (Constant False-Alarm Rate) Radar Signal Detection

DTIC Science & Technology

1987-10-01

SIICILE COPY 4 F FInI Tedwill Rlmrt to October 197 00 C\\JT ON ADAPTIVE CELL-AVERA81NG CFAR I RADAR SIGNAL DETECTION Syracuse University Mourud krket...NY 13441-5700 ELEMENT NO. NO. NO ACCESSION NO. 11. TITLE (Include Security Classification) 61102F 2’ 05 J8 PD - ON ADAPTIVE CELL-AVERAGING CFAR RADAR... CFAR ). One approach to adaptive detection in nonstationary noise and clutter background is to compare the processed target signal to an adaptive

Clearance of chlamydial elementary bodies from the conjunctival sac

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, H.R.; Velez, V.L.

1987-07-01

The rate of disappearance of inactivated Chlamydia trachomatis elementary body (EB) preparations from the conjunctival sac was studied in monkeys. Direct fluorescent antibody (DFA) cytology showed that the majority of EB had been cleared from the eye within 24 hr of the inoculation of 1 X 10(6) inactivated EB, although small numbers of EB could be detected for up to 144 hr. The rate of clearance in normal and ocular immune animals did not differ, and formalin-killed and UV-inactivated EBs disappeared at a comparable rate. These studies suggest that chlamydial EB are cleared relatively quickly from the eye and supportmore » the notion that EBs detected by DFA cytology indicate the presence of current infection.« less

Dutch digital breast cancer screening: implications for breast cancer care.

PubMed

Timmers, Johanna M; den Heeten, Gerard J; Adang, Eddy M; Otten, Johannes D; Verbeek, André L; Broeders, Mireille J

2012-12-01

In comparison to other European population-based breast cancer screening programmes, the Dutch programme has a low referral rate, similar breast cancer detection and a high breast cancer mortality reduction. The referral rate in the Netherlands has increased over time and is expected to rise further, mainly following nationwide introduction of digital mammography, completed in 2010. This study explores the consequences of the introduction of digital mammography on the balance between referral rate, detection of breast cancer, diagnostic work-up and associated costs. Detailed information on diagnostic work-up (chart review) was obtained from referred women (n = 988) in 2000-06 (100% analogue mammography) and 2007 (75% digital mammography) in Nijmegen, the Netherlands. The average referral rate increased from 15 (2000-06) to 34 (2007) per 1000 women screened. The number of breast cancers detected increased from 5.5 to 7.8 per 1000 screens, whereas the positive predictive value fell from 37% to 23%. A sharp rise in diagnostic work-up procedures and total diagnostic costs was seen. On the other hand, costs of a single work-up slightly decreased, as less surgical biopsies were performed. Our study shows that a low referral rate in combination with the introduction of digital mammography affects the balance between referral rate and detection rate and can substantially influence breast cancer care and associated costs. Referral rates in the Netherlands are now more comparable to other countries. This effect is therefore of value in countries where implementation of digital breast cancer screening has just started or is still under discussion.

The Value of Audio Devices in the Endoscopy Room (VADER) study: a randomised controlled trial.

PubMed

Ardalan, Zaid Sm; Vasudevan, Abhinav; Hew, Simon; Schulberg, Julien; Lontos, Steve

2015-12-14

To evaluate the effect of Star Wars music (SWM) compared with endoscopist-selected popular music (PM) on quality outcomes in colonoscopy. A single-centre, prospective, randomised controlled trial conducted in an endoscopy suite within a quaternary-centre gastroenterology unit, Melbourne, Australia. The primary outcome measures were procedure time, polyp detection rate (PDR) and adenoma detection rate (ADR). The secondary outcome measure was adenomas per colonoscopy (APC). 103 colonoscopies were analysed: 58 in the SWM group and 45 in the PM group. Bowel preparation was assessed as good or excellent in 57% of the SWM group compared with 69% of the PM group (P < 0.01). The PDR was significantly higher in the SWM group than in the PM group (60% v 35%; P = 0.006). Similarly, the ADR was significantly higher in the SWM group than in the PM group (48% v 27%; P = 0.01). The APC in the SWM group was 84% compared with 35% in the PM group (P = 0.01). SWM compared with PM improves key quality outcomes in colonoscopy, despite poorer bowel preparation.

Simultaneous (68)Ga-DOTA-TOC PET/MRI with gadoxetate disodium in patients with neuroendocrine tumor.

PubMed

Hope, Thomas A; Pampaloni, Miguel Hernandez; Nakakura, Eric; VanBrocklin, Henry; Slater, James; Jivan, Salma; Aparici, Carina Mari; Yee, Judy; Bergsland, Emily

2015-08-01

To evaluate a simultaneous PET/MRI approach to imaging patients with neuroendocrine tumor using a combination of (68)Ga-DOTA-TOC as a PET contrast agent and gadoxetate disodium as a hepatobiliary MRI contrast agent. Ten patients with neuroendocrine tumor with known or suspected hepatic disease were imaged using a (68)Ga-DOTA-TOC PET/CT immediately followed by a 3.0T time-of-flight PET/MRI, using a combined whole body and liver specific imaging. The presence of lesions and DOTA-TOC avidity were assessed on CT, PET from PET/CT, diffusion weighted imaging, hepatobiliary phase imaging (HBP), and PET from PET/MRI. Maximum standardized uptake values (SUVmax) in hepatic lesions and nodal metastases were compared between PET/CT and PET/MRI, as were detection rates using each imaging approach. A total of 101 hepatic lesions were identified, 47 of which were DOTA-TOC avid and able to be individually measured on both PET/CT and PET/MRI. HBP imaging had a higher sensitivity for detection of hepatic lesions compared to CT or PET (99% vs. 46% and 64%, respectively; p values <0.001). There was a strong correlation between SUVmax of liver lesions obtained with PET/CT compared to PET/MR imaging (Pearson's correlation = 0.91). For nodal disease, CT had a higher sensitivity compared to whole body MRI (p = 0.015), although PET acquired from PET/MRI detected slightly more lesions compared to PET from PET/CT. A simultaneous PET/MRI using both (68)Ga-DOTA-TOC and gadoxetate disodium was successful in whole body staging of patients with neuroendocrine tumor. HBP imaging had an increased detection rate for hepatic metastases.

Pedestrian detection in infrared image using HOG and Autoencoder

NASA Astrophysics Data System (ADS)

Chen, Tianbiao; Zhang, Hao; Shi, Wenjie; Zhang, Yu

2017-11-01

In order to guarantee the safety of driving at night, vehicle-mounted night vision system was used to detect pedestrian in front of cars and send alarm to prevent the potential dangerous. To decrease the false positive rate (FPR) and increase the true positive rate (TPR), a pedestrian detection method based on HOG and Autoencoder (HOG+Autoencoder) was presented. Firstly, the HOG features of input images were computed and encoded by Autoencoder. Then the encoded features were classified by Softmax. In the process of training, Autoencoder was trained unsupervised. Softmax was trained with supervision. Autoencoder and Softmax were stacked into a model and fine-tuned by labeled images. Experiment was conducted to compare the detection performance between HOG and HOG+Autoencoder, using images collected by vehicle-mounted infrared camera. There were 80000 images for training set and 20000 for the testing set, with a rate of 1:3 between positive and negative images. The result shows that when TPR is 95%, FPR of HOG+Autoencoder is 0.4%, while the FPR of HOG is 5% with the same TPR.

Adding Endoscopist-Directed Flexible Endoscopic Evaluation of Swallowing to the Videofluoroscopic Swallowing Study Increased the Detection Rates of Penetration, Aspiration, and Pharyngeal Residue.

PubMed

Park, Won Young; Lee, Tae Hee; Ham, Nam Seok; Park, Ji Woong; Lee, Yang Gyun; Cho, Sang Jin; Lee, Joon Seong; Hong, Su Jin; Jeon, Seong Ran; Kim, Hyun Gun; Cho, Joo Young; Kim, Jin Oh; Cho, Jun Hyung; Lee, Ji Sung

2015-09-23

Currently, the videofluoroscopic swallowing study (VFSS) is the standard tool for evaluating dysphagia. We evaluated whether the addition of endoscopist-directed flexible endoscopic evaluation of swallowing (FEES) to VFSS could improve the detection rates of penetration, aspiration, and pharyngeal residue, compared the diagnostic efficacy between VFSS and endoscopist-directed FEES and assessed the adverse events of the FEES. In single tertiary referral center, a retrospective analysis of prospectively collected data was conducted. Fifty consecutive patients suspected of oropharyngeal dysphagia were enrolled in this study between January 2012 and July 2012. The agreement in the detection of penetration and aspiration between VFSS and FEES of viscous food (κ=0.34; 95% confidence interval [CI], 0.15 to 0.53) and liquid food (κ=0.22; 95% CI, 0.02 to 0.42) was "fair." The agreement in the detection of pharyngeal residue between the two tests was "substantial" with viscous food (κ=0.63; 95% CI, 0.41 to 0.94) and "fair" with liquid food (κ=0.37; 95% CI, 0.10 to 0.63). Adding FEES to VFSS significantly increased the detection rates of penetration, aspiration, and pharyngeal residue. No severe adverse events were noted during FEES, except for two cases of epistaxis, which stopped spontaneously without requiring any packing. This study demonstrated that the addition of endoscopist-directed FEES to VFSS increased the detection rates of penetration, aspiration, and pharyngeal residue.

Treatment changes and long-term recurrence rates after hexaminolevulinate (HAL) fluorescence cystoscopy: does it really make a difference in patients with non-muscle-invasive bladder cancer (NMIBC)?

PubMed

Geavlete, Bogdan; Multescu, Razvan; Georgescu, Dragos; Jecu, Marian; Stanescu, Florin; Geavlete, Petrisor

2012-02-01

•  To evaluate in a prospective, randomized study the impact of hexaminolevulinate blue-light cystoscopy (HAL-BLC) on the diagnostic accuracy and treatment changes in cases of non-muscle invasive bladder cancer (NMIBC) compared with standard white-light cystoscopy (WLC). •  To compare the long-term recurrence rates in the two study arms. •  In all, 362 patients suspected of NMIBC were included in the trial based on positive urinary cytology and/or ultrasonographic suspicion of bladder tumours and underwent transurethral resection of bladder tumours. •  A single postoperative mytomicin-C instillation was performed in all cases, intravesical chemotherapy for intermediate-risk patients and BCG instillations for high-risk cases. •  The follow-up protocol consisted of urinary cytology and WLC every 3 months for 2 years. •  Only first-time recurrences after the initial diagnosis were considered. •  In the 142 patients with NMIBC in the HAL-BLC series, tumour detection rates significantly improved for carcinoma in situ, pTa andoverall cases. •  In 35.2% of the cases, additional malignant lesions were found by HAL-BLC and consequently, the recurrence- and progression-risk categories of patients and subsequent treatment improved in 19% of the cases due to fluorescence cystoscopy. •  In all, 125 patients in the HAL-BLC group and 114 of the WLC group completed the follow-up. •  The recurrence rate at 3 months was lower in the HAL-BLC series (7.2% vs 15.8%) due to fewer 'other site' recurrences when compared with the WLC series (0.8% vs 6.1%). •  The 1 and 2 years recurrence rates were significantly decreased in the HAL-BLC group compared with the WLC group (21.6% vs 32.5% and 31.2% vs 45.6%, respectively). •  HAL-BLC was better than WLC for detecting NMIBC cases and improved tumour detection rates. •  HAL-BLC significantly modified the postoperative treatment of cases. •  The 3 months, 1 and 2 years recurrence rates were significantly improved in the HAL-BLC arm. © 2011 THE AUTHORS. BJU INTERNATIONAL © 2011 BJU INTERNATIONAL.

Traffic Sign Detection System for Locating Road Intersections and Roundabouts: The Chilean Case.

PubMed

Villalón-Sepúlveda, Gabriel; Torres-Torriti, Miguel; Flores-Calero, Marco

2017-05-25

This paper presents a traffic sign detection method for signs close to road intersections and roundabouts, such as stop and yield (give way) signs. The proposed method relies on statistical templates built using color information for both segmentation and classification. The segmentation method uses the RGB-normalized (ErEgEb) color space for ROIs (Regions of Interest) generation based on a chromaticity filter, where templates at 10 scales are applied to the entire image. Templates consider the mean and standard deviation of normalized color of the traffic signs to build thresholding intervals where the expected color should lie for a given sign. The classification stage employs the information of the statistical templates over YCbCr and ErEgEb color spaces, for which the background has been previously removed by using a probability function that models the probability that the pixel corresponds to a sign given its chromaticity values. This work includes an analysis of the detection rate as a function of the distance between the vehicle and the sign. Such information is useful to validate the robustness of the approach and is often not included in the existing literature. The detection rates, as a function of distance, are compared to those of the well-known Viola-Jones method. The results show that for distances less than 48 m, the proposed method achieves a detection rate of 87.5 % and 95.4 % for yield and stop signs, respectively. For distances less than 30 m, the detection rate is 100 % for both signs. The Viola-Jones approach has detection rates below 20 % for distances between 30 and 48 m, and barely improves in the 20-30 m range with detection rates of up to 60 % . Thus, the proposed method provides a robust alternative for intersection detection that relies on statistical color-based templates instead of shape information. The experiments employed videos of traffic signs taken in several streets of Santiago, Chile, using a research platform implemented at the Robotics and Automation Laboratory of PUC to develop driver assistance systems.

Traffic Sign Detection System for Locating Road Intersections and Roundabouts: The Chilean Case

PubMed Central

Villalón-Sepúlveda, Gabriel; Torres-Torriti, Miguel; Flores-Calero, Marco

2017-01-01

This paper presents a traffic sign detection method for signs close to road intersections and roundabouts, such as stop and yield (give way) signs. The proposed method relies on statistical templates built using color information for both segmentation and classification. The segmentation method uses the RGB-normalized (ErEgEb) color space for ROIs (Regions of Interest) generation based on a chromaticity filter, where templates at 10 scales are applied to the entire image. Templates consider the mean and standard deviation of normalized color of the traffic signs to build thresholding intervals where the expected color should lie for a given sign. The classification stage employs the information of the statistical templates over YCbCr and ErEgEb color spaces, for which the background has been previously removed by using a probability function that models the probability that the pixel corresponds to a sign given its chromaticity values. This work includes an analysis of the detection rate as a function of the distance between the vehicle and the sign. Such information is useful to validate the robustness of the approach and is often not included in the existing literature. The detection rates, as a function of distance, are compared to those of the well-known Viola–Jones method. The results show that for distances less than 48 m, the proposed method achieves a detection rate of 87.5% and 95.4% for yield and stop signs, respectively. For distances less than 30 m, the detection rate is 100% for both signs. The Viola–Jones approach has detection rates below 20% for distances between 30 and 48 m, and barely improves in the 20–30 m range with detection rates of up to 60%. Thus, the proposed method provides a robust alternative for intersection detection that relies on statistical color-based templates instead of shape information. The experiments employed videos of traffic signs taken in several streets of Santiago, Chile, using a research platform implemented at the Robotics and Automation Laboratory of PUC to develop driver assistance systems. PMID:28587071

Effect of hydrodynamical-simulation–inspired dark matter velocity profile on directional detection of dark matter

DOE PAGES

Laha, Ranjan

2018-02-01

Directional detection is an important way to detect dark matter. An input for these experiments is the dark matter velocity distribution. Recent hydrodynamical simulations have shown that the dark matter velocity distribution differs substantially from the Standard Halo Model. We study the impact of some of these updated velocity distributions in dark matter directional detection experiments. Here, we calculate the ratio of events required to confirm the forward-backward asymmetry and the existence of the ring of maximum recoil rate using different dark matter velocity distributions for 19F and Xe targets. We show that with the use of updated dark mattermore » velocity profiles, the forward-backward asymmetry and the ring of maximum recoil rate can be confirmed using a factor of ~ 2– 3 less events when compared to that using the Standard Halo Model.« less

Effect of hydrodynamical-simulation–inspired dark matter velocity profile on directional detection of dark matter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Laha, Ranjan

Directional detection is an important way to detect dark matter. An input for these experiments is the dark matter velocity distribution. Recent hydrodynamical simulations have shown that the dark matter velocity distribution differs substantially from the Standard Halo Model. We study the impact of some of these updated velocity distributions in dark matter directional detection experiments. Here, we calculate the ratio of events required to confirm the forward-backward asymmetry and the existence of the ring of maximum recoil rate using different dark matter velocity distributions for 19F and Xe targets. We show that with the use of updated dark mattermore » velocity profiles, the forward-backward asymmetry and the ring of maximum recoil rate can be confirmed using a factor of ~ 2– 3 less events when compared to that using the Standard Halo Model.« less

Improving detection of low SNR targets using moment-based detection

NASA Astrophysics Data System (ADS)

Young, Shannon R.; Steward, Bryan J.; Hawks, Michael; Gross, Kevin C.

2016-05-01

Increases in the number of cameras deployed, frame rate, and detector array sizes have led to a dramatic increase in the volume of motion imagery data that is collected. Without a corresponding increase in analytical manpower, much of the data is not analyzed to full potential. This creates a need for fast, automated, and robust methods for detecting signals of interest. Current approaches fall into two categories: detect-before-track (DBT), which are fast but often poor at detecting dim targets, and track-before-detect (TBD) methods which can offer better performance but are typically much slower. This research seeks to contribute to the near real time detection of low SNR, unresolved moving targets through an extension of earlier work on higher order moments anomaly detection, a method that exploits both spatial and temporal information but is still computationally efficient and massively parallelizable. It was found that intelligent selection of parameters can improve probability of detection by as much as 25% compared to earlier work with higherorder moments. The present method can reduce detection thresholds by 40% compared to the Reed-Xiaoli anomaly detector for low SNR targets (for a given probability of detection and false alarm).

Prebiopsy Multiparametric Magnetic Resonance Imaging for Prostate Cancer Diagnosis in Biopsy-naive Men with Suspected Prostate Cancer Based on Elevated Prostate-specific Antigen Values: Results from a Randomized Prospective Blinded Controlled Trial.

PubMed

Tonttila, Panu P; Lantto, Juha; Pääkkö, Eija; Piippo, Ulla; Kauppila, Saila; Lammentausta, Eveliina; Ohtonen, Pasi; Vaarala, Markku H

2016-03-01

Multiparametric magnetic resonance imaging (MP-MRI) may improve the detection of clinically significant prostate cancer (PCa). To compare MP-MRI transrectal ultrasound (TRUS)-fusion targeted biopsy with routine TRUS-guided random biopsy for overall and clinically significant PCa detection among patients with suspected PCa based on prostate-specific antigen (PSA) values. This institutional review board-approved, single-center, prospective, randomized controlled trial (April 2011 to December 2014) included 130 biopsy-naive patients referred for prostate biopsy based on PSA values (PSA <20 ng/ml or free-to-total PSA ratio ≤0.15 and PSA <10 ng/ml). Patients were randomized 1:1 to the MP-MRI or control group. Patients in the MP-MRI group underwent prebiopsy MP-MRI followed by 10- to 12-core TRUS-guided random biopsy and cognitive MRI/TRUS fusion targeted biopsy. The control group underwent TRUS-guided random biopsy alone. MP-MRI 3-T phased-array surface coil. The primary outcome was the number of patients with biopsy-proven PCa in the MP-MRI and control groups. Secondary outcome measures included the number of positive prostate biopsies and the proportion of clinically significant PCa in the MP-MRI and control groups. Between-group analyses were performed. Overall, 53 and 60 patients were evaluable in the MP-MRI and control groups, respectively. The overall PCa detection rate and the clinically significant cancer detection rate were similar between the MP-MRI and control groups, respectively (64% [34 of 53] vs 57% [34 of 60]; 7.5% difference [95% confidence interval (CI), -10 to 25], p=0.5, and 55% [29 of 53] vs 45% [27 of 60]; 9.7% difference [95% CI, -8.5 to 27], p=0.8). The PCa detection rate was higher than assumed during the planning of this single-center trial. MP-MRI/TRUS-fusion targeted biopsy did not improve PCa detection rate compared with TRUS-guided biopsy alone in patients with suspected PCa based on PSA values. In this randomized clinical trial, additional prostate magnetic resonance imaging (MRI) before prostate biopsy appeared to offer similar diagnostic accuracy compared with routine transrectal ultrasound-guided random biopsy in the diagnosis of prostate cancer. Similar numbers of cancers were detected with and without MRI. ClinicalTrials.gov identifier: NCT01357512. Copyright © 2015 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Automatic mouse ultrasound detector (A-MUD): A new tool for processing rodent vocalizations.

PubMed

Zala, Sarah M; Reitschmidt, Doris; Noll, Anton; Balazs, Peter; Penn, Dustin J

2017-01-01

House mice (Mus musculus) emit complex ultrasonic vocalizations (USVs) during social and sexual interactions, which have features similar to bird song (i.e., they are composed of several different types of syllables, uttered in succession over time to form a pattern of sequences). Manually processing complex vocalization data is time-consuming and potentially subjective, and therefore, we developed an algorithm that automatically detects mouse ultrasonic vocalizations (Automatic Mouse Ultrasound Detector or A-MUD). A-MUD is a script that runs on STx acoustic software (S_TOOLS-STx version 4.2.2), which is free for scientific use. This algorithm improved the efficiency of processing USV files, as it was 4-12 times faster than manual segmentation, depending upon the size of the file. We evaluated A-MUD error rates using manually segmented sound files as a 'gold standard' reference, and compared them to a commercially available program. A-MUD had lower error rates than the commercial software, as it detected significantly more correct positives, and fewer false positives and false negatives. The errors generated by A-MUD were mainly false negatives, rather than false positives. This study is the first to systematically compare error rates for automatic ultrasonic vocalization detection methods, and A-MUD and subsequent versions will be made available for the scientific community.

Compact cosmic ray detector for unattended atmospheric ionization monitoring

NASA Astrophysics Data System (ADS)

Aplin, K. L.; Harrison, R. G.

2010-12-01

Two vertical cosmic ray telescopes for atmospheric cosmic ray ionization event detection are compared. Counter A, designed for low power remote use, was deployed in the Welsh mountains; its event rate increased with altitude as expected from atmospheric cosmic ray absorption. Independently, Counter B's event rate was found to vary with incoming particle acceptance angle. Simultaneous co-located comparison of both telescopes exposed to atmospheric ionization showed a linear relationship between their event rates.

A Real-Time Wireless Sweat Rate Measurement System for Physical Activity Monitoring

PubMed Central

Brueck, Andrew; Iftekhar, Tashfin; Stannard, Alicja B.; Kaya, Tolga

2018-01-01

There has been significant research on the physiology of sweat in the past decade, with one of the main interests being the development of a real-time hydration monitor that utilizes sweat. The contents of sweat have been known for decades; sweat provides significant information on the physiological condition of the human body. However, it is important to know the sweat rate as well, as sweat rate alters the concentration of the sweat constituents, and ultimately affects the accuracy of hydration detection. Towards this goal, a calorimetric based flow-rate detection system was built and tested to determine sweat rate in real time. The proposed sweat rate monitoring system has been validated through both controlled lab experiments (syringe pump) and human trials. An Internet of Things (IoT) platform was embedded, with the sensor using a Simblee board and Raspberry Pi. The overall prototype is capable of sending sweat rate information in real time to either a smartphone or directly to the cloud. Based on a proven theoretical concept, our overall system implementation features a pioneer device that can truly measure the rate of sweat in real time, which was tested and validated on human subjects. Our realization of the real-time sweat rate watch is capable of detecting sweat rates as low as 0.15 µL/min/cm2, with an average error in accuracy of 18% compared to manual sweat rate readings. PMID:29439398

Using Satellite Data to Characterize the Temporal Thermal Behavior of an Active Volcano: Mount St. Helens, WA

NASA Technical Reports Server (NTRS)

Vaughan, R. Greg; Hook, Simon J.

2006-01-01

ASTER thermal infrared data over Mt. St Helens were used to characterize its thermal behavior from Jun 2000 to Feb 2006. Prior to the Oct 2004 eruption, the average crater temperature varied seasonally between -12 and 6 C. After the eruption, maximum single-pixel temperature increased from 10 C (Oct 2004) to 96 C (Aug 2005), then showed a decrease to Feb 2006. The initial increase in temperature was correlated with dome morphology and growth rate and the subsequent decrease was interpreted to relate to both seasonal trends and a decreased growth rate/increased cooling rate, possibly suggesting a significant change in the volcanic system. A single-pixel ASTER thermal anomaly first appeared on Oct 1, 2004, eleven hours after the first eruption - 10 days before new lava was exposed at the surface. By contrast, an automated algorithm for detecting thermal anomalies in MODIS data did not trigger an alert until Dec 18. However, a single-pixel thermal anomaly first appeared in MODIS channel 23 (4 um) on Oct 13, 12 days after the first eruption - 2 days after lava was exposed. The earlier thermal anomaly detected with ASTER data is attributed to the higher spatial resolution (90 m) compared with MODIS (1 m) and the earlier visual observation of anomalous pixels compared to the automated detection method suggests that local spatial statistics and background radiance data could improve automated detection methods.

Long-Term Storage at -80°C: Effect on Rate of Recovery of Mycobacterium tuberculosis From Direct Acid-Fast Bacilli Smear-Positive Sputum Samples.

PubMed

Shinu, Pottathil; AshokKumar Singh, Varsha; Nair, Anroop; Farooq, Rumana; Ishaq, Sheikh

2016-09-01

The aim of this study was to evaluate the difference in the rate of recovery of Mycobacterium tuberculosis (MTB) from routinely cultured sputum and long-term stored sputum specimens (at -80°C) using Löwenstein-Jensen (LJ) media, Mycobacterium Growth Indicator Tube (BBL MGIT(TM) ), and Middlebrook 7H11 (MB 7H11) agar. Direct acid-fast bacilli smear-positive sputum specimens (both before and after storage [n = 136]) were studied (after culturing on LJ media, BBL MGIT(TM) , and MB 7H11 agar) and the performances were compared. For the detection of MTB, BBL MGIT(TM) and MB 7H11 agar (before storage) demonstrated a sensitivity, specificity, positive predictive value (PPV) of 98.28%, 30.77%, 92.68%, 66.67%, and negative predictive value (NPV) of 97.41%, 30.77%, 92.62%, 57.14%, respectively, when compared to LJ media (before storage). Similarly, BBL MGIT(TM) and MB 7H11 agar (after storage) demonstrated a sensitivity, specificity, PPV, and NPV of 95.5%, 38.89%, 90.6%, 58.33%, and 95.5%, 66.67 %, 94.64%, 70.59%, respectively, when compared to LJ media (after storage) for the detection of MTB. None of the culture techniques independently (both before and after storage) detected growth of MTB from all the sputum specimens studied. However, BBL MGIT(TM) system and LJ media combination (both before and after storage) effectively detected the growth of MTB from sputum specimens when compared to other culture technique combinations. © 2015 Wiley Periodicals, Inc.

Comparative Evaluation of Four Real-Time PCR Methods for the Quantitative Detection of Epstein-Barr Virus from Whole Blood Specimens.

PubMed

Buelow, Daelynn; Sun, Yilun; Tang, Li; Gu, Zhengming; Pounds, Stanley; Hayden, Randall

2016-07-01

Monitoring of Epstein-Barr virus (EBV) load in immunocompromised patients has become integral to their care. An increasing number of reagents are available for quantitative detection of EBV; however, there are little published comparative data. Four real-time PCR systems (one using laboratory-developed reagents and three using analyte-specific reagents) were compared with one another for detection of EBV from whole blood. Whole blood specimens seeded with EBV were used to determine quantitative linearity, analytical measurement range, lower limit of detection, and CV for each assay. Retrospective testing of 198 clinical samples was performed in parallel with all methods; results were compared to determine relative quantitative and qualitative performance. All assays showed similar performance. No significant difference was found in limit of detection (3.12-3.49 log10 copies/mL; P = 0.37). A strong qualitative correlation was seen with all assays that used clinical samples (positive detection rates of 89.5%-95.8%). Quantitative correlation of clinical samples across assays was also seen in pairwise regression analysis, with R(2) ranging from 0.83 to 0.95. Normalizing clinical sample results to IU/mL did not alter the quantitative correlation between assays. Quantitative EBV detection by real-time PCR can be performed over a wide linear dynamic range, using three different commercially available reagents and laboratory-developed methods. EBV was detected with comparable sensitivity and quantitative correlation for all assays. Copyright © 2016 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

Skin Color Segmentation Using Coarse-to-Fine Region on Normalized RGB Chromaticity Diagram for Face Detection

NASA Astrophysics Data System (ADS)

Soetedjo, Aryuanto; Yamada, Koichi

This paper describes a new color segmentation based on a normalized RGB chromaticity diagram for face detection. Face skin is extracted from color images using a coarse skin region with fixed boundaries followed by a fine skin region with variable boundaries. Two newly developed histograms that have prominent peaks of skin color and non-skin colors are employed to adjust the boundaries of the skin region. The proposed approach does not need a skin color model, which depends on a specific camera parameter and is usually limited to a particular environment condition, and no sample images are required. The experimental results using color face images of various races under varying lighting conditions and complex backgrounds, obtained from four different resources on the Internet, show a high detection rate of 87%. The results of the detection rate and computation time are comparable to the well known real-time face detection method proposed by Viola-Jones [11], [12].

Automated Epileptic Seizure Detection Based on Wearable ECG and PPG in a Hospital Environment

PubMed Central

De Cooman, Thomas; Gu, Ying; Cleeren, Evy; Claes, Kasper; Van Paesschen, Wim; Van Huffel, Sabine; Hunyadi, Borbála

2017-01-01

Electrocardiography has added value to automatically detect seizures in temporal lobe epilepsy (TLE) patients. The wired hospital system is not suited for a long-term seizure detection system at home. To address this need, the performance of two wearable devices, based on electrocardiography (ECG) and photoplethysmography (PPG), are compared with hospital ECG using an existing seizure detection algorithm. This algorithm classifies the seizures on the basis of heart rate features, extracted from the heart rate increase. The algorithm was applied to recordings of 11 patients in a hospital setting with 701 h capturing 47 (fronto-)temporal lobe seizures. The sensitivities of the hospital system, the wearable ECG device and the wearable PPG device were respectively 57%, 70% and 32%, with corresponding false alarms per hour of 1.92, 2.11 and 1.80. Whereas seizure detection performance using the wrist-worn PPG device was considerably lower, the performance using the wearable ECG is proven to be similar to that of the hospital ECG. PMID:29027928

Automated Epileptic Seizure Detection Based on Wearable ECG and PPG in a Hospital Environment.

PubMed

Vandecasteele, Kaat; De Cooman, Thomas; Gu, Ying; Cleeren, Evy; Claes, Kasper; Paesschen, Wim Van; Huffel, Sabine Van; Hunyadi, Borbála

2017-10-13

Electrocardiography has added value to automatically detect seizures in temporal lobe epilepsy (TLE) patients. The wired hospital system is not suited for a long-term seizure detection system at home. To address this need, the performance of two wearable devices, based on electrocardiography (ECG) and photoplethysmography (PPG), are compared with hospital ECG using an existing seizure detection algorithm. This algorithm classifies the seizures on the basis of heart rate features, extracted from the heart rate increase. The algorithm was applied to recordings of 11 patients in a hospital setting with 701 h capturing 47 (fronto-)temporal lobe seizures. The sensitivities of the hospital system, the wearable ECG device and the wearable PPG device were respectively 57%, 70% and 32%, with corresponding false alarms per hour of 1.92, 2.11 and 1.80. Whereas seizure detection performance using the wrist-worn PPG device was considerably lower, the performance using the wearable ECG is proven to be similar to that of the hospital ECG.

Spoofing detection on facial images recognition using LBP and GLCM combination

NASA Astrophysics Data System (ADS)

Sthevanie, F.; Ramadhani, K. N.

2018-03-01

The challenge for the facial based security system is how to detect facial image falsification such as facial image spoofing. Spoofing occurs when someone try to pretend as a registered user to obtain illegal access and gain advantage from the protected system. This research implements facial image spoofing detection method by analyzing image texture. The proposed method for texture analysis combines the Local Binary Pattern (LBP) and Gray Level Co-occurrence Matrix (GLCM) method. The experimental results show that spoofing detection using LBP and GLCM combination achieves high detection rate compared to that of using only LBP feature or GLCM feature.

International collaboration between Japan and Chile to improve detection rates in colorectal cancer screening.

PubMed

Okada, Takuya; Tanaka, Koji; Kawachi, Hiroshi; Ito, Takashi; Nishikage, Tetsuro; Odagaki, Tomoyuki; Zárate, Alejandro J; Kronberg, Udo; López-Köstner, Francisco; Karelovic, Stanko; Flores, Sergio; Estela, Ricardo; Tsubaki, Masahiro; Uetake, Hiroyuki; Eishi, Yoshinobu; Kawano, Tatsuyuki

2016-01-01

In Chile, mortality from colorectal cancer (CRC) has increased rapidly. To help address this issue, the Prevention Project for Neoplasia of the Colon and Rectum (PRENEC) program was initiated in 2012 with intensive support from Tokyo Medical and Dental University (TMDU) in Tokyo, Japan, as part of an international collaboration. From June 2012 to July 2014, a total of 10,575 asymptomatic participants were enrolled in PRENEC. Participants with positive immunochemical fecal occult blood test (iFOBT) results or a family history of CRC underwent colonoscopy. The colonoscopy results from a similar, previous project in Chile (PREVICOLON) were compared with those from PRENEC. Furthermore, the initial colonoscopies of 1562 participants in PRENEC were analyzed according to whether the colonoscopists were from TMDU or Chile. The complete colonoscopy, adenoma detection, and cancer detection rates were 88.0%, 26.7%, and 1.1%, respectively, in PREVICOLON, while the corresponding values were 94.4%, 41.8%, and 6.0%, respectively, in PRENEC. In PRENEC, 107 cases of CRC were detected, amounting for 1.0% of all participants. Considering initial colonoscopies in PRENEC, the complete colonoscopy, adenoma detection, and cancer detection rates were 97.4%, 45.3%, and 9.3%, respectively, for physicians at TMDU and 93.3%, 41.5%, and 5.1%, respectively for Chilean physicians. The detection rates of intramucosal cancer were 7.3% and 3.7%, respectively, for TMDU and Chilean physicians. Quality indicators of colonoscopy substantially improved from PREVICOLON to PRENEC. The assessments made by Chilean physicians alone were improved in PRENEC, but remained better in the TMDU group. Moreover, physicians from TMDU detected more CRCs than Chilean physicians, especially at earlier stages. © 2015 American Cancer Society.

Assessment of a new piezoelectric transducer sensor for noninvasive cardiorespiratory monitoring of newborn infants in the NICU.

PubMed

Sato, Shinichi; Ishida-Nakajima, Wako; Ishida, Akira; Kawamura, Masanari; Miura, Shinobu; Ono, Kyoichi; Inagaki, Nobuya; Takada, Goro; Takahashi, Tsutomu

2010-01-01

Electrocardiogram (ECG) and impedance pneumography (IPG), the most widely used techniques for cardiorespiratory monitoring in the neonatal intensive care unit (NICU), have the disadvantage of causing skin damage when used for very premature newborn infants. To prevent skin damage, we designed a new piezoelectric transducer (PZT) sensor. To assess the potential of the PZT sensor for cardiorespiratory monitoring in the NICU. The PZT sensor was placed under a folded towel under a neonate to detect an acoustic cardiorespiratory signal, from which heart rate (HR) and breathing rate (BR) were calculated, together with simultaneous ECG/IPG recording for 1-9 days for long and brief (1-min) assessment. The brief assessment showed average correlation coefficients of 0.92 +/- 0.12 and 0.95 +/- 0.02 between instantaneous HRs/BRs detected by the PZT sensor and ECG/IPG in 27 and 11 neonates examined. During the long assessment, the HR detection rate by the PZT sensor was approximately 10% lower than that by ECG (82.6 +/- 12.9 vs. 91.8 +/- 4.1%; p = 0.001, n = 27), although comparable (90.3 +/- 4.1 vs. 92.5 +/- 3.4%, p = 0.081) in approximately 70% (18/27) of neonates examined; BR detection rate was comparable between the PZT sensor and IPG during relatively stable signal conditions (95.9 +/- 4.0 vs. 95.3 +/- 3.5%; p = 0.38, n = 11). The PZT sensor caused neither skin damage nor body movement increase in all neonates examined. The PZT sensor is noninvasive and does not cause skin irritation, and we believe it does provide a reliable, accurate cardiorespiratory monitoring tool for use in the NICU, although the issue of mechanical-ventilation noise remains to be solved. Copyright 2010 S. Karger AG, Basel.

Cervical human papilloma virus (HPV) DNA primary screening test: Results of a population-based screening programme in central Italy.

PubMed

Passamonti, Basilio; Gustinucci, Daniela; Giorgi Rossi, Paolo; Cesarini, Elena; Bulletti, Simonetta; Carlani, Angela; Martinelli, Nadia; Broccolini, Massimo; D'Angelo, Valentina; D'Amico, Maria Rosaria; Di Dato, Eugenio; Galeazzi, Paola; Malaspina, Morena; Spita, Nicoletta; Tintori, Beatrice; Giaimo, Maria Donata

2017-09-01

Objective To present the results of the first and second round human papilloma virus (HPV)-based screening programme in the Umbria region after three years. Methods From August 2010 to November 2011, the entire female population aged 35-64 in a local health district was invited for HPV testing (HPV-DNA cobas4800 on a liquid-based cytology sample). HPV-negative women were re-invited after three years. For HPV-positive women, a slide was prepared and interpreted. Positive cytologies were referred to colposcopy; negatives were referred to repeat HPV after one year. If HPV was persistently positive, women were referred to colposcopy; if negative, to normal screening. Indicators of the first and second round are compared with those of cytology screening in the same area in the preceding three years. Results Participation was 56.5%, the same as cytology (56.6%). HPV-positivity was 6.4% (396/6272), cytology triage positivity was 35.6%; 251 cytology negative women were referred to one-year HPV retesting, 84.1% complied, and 55.5% were positive. Total colposcopy referral was 4.1%, and for cytology 1%. The detection rate for cervical intraepithelial neoplasia grade 2 or more severe was 10‰, compared with 3.7‰ using cytology. After three years, HPV-positivity was 3.4% (129/3831), overall colposcopy referral was 2.3% (most at one-year follow-up), and detection rate was 0.5/1000. Conclusions The first round detection rate was more than twice that of cytology screening, while colposcopy referral increased fourfold. At the second round, the detection rate decreased dramatically, showing that longer interval and more conservative protocols are needed.

Performance indicators evaluation of the population-based breast cancer screening programme in Northern Portugal using the European Guidelines.

PubMed

Bento, Maria José; Gonçalves, Guilherme; Aguiar, Ana; Castro, Clara; Veloso, Vitor; Rodrigues, Vítor

2015-10-01

To evaluate the first 10 years of operation of the population-based breast cancer screening programme implemented in the Northern Region of Portugal, using selected recommended standard performance indicators. Data from women aged 50-69 screened with two-view mammography, biennially, in the period 2000-2009, were included. Main performance indicators were compared with the recommended levels of the European Guidelines. A total of 202,039 screening examinations were performed, 71,731 (35.5%) in the initial screening and 130,308 (64.5%) in the subsequent screening. Coverage rate by examination reached 74.3% of the target population, in the last period evaluated. Recall rates were 8.1% and 2.4% and cancer detection rates were 4.4/1000 and 2.9/1000 respectively, for initial and subsequent screenings. The breast cancer detection rate, expressed as a multiple of the background expected incidence was 3.1 in initial screen and 2.2 in subsequent screen. The incidence of invasive interval cancers met the desirable recommended levels both the first and second years since last screening examination, in the initial and subsequent screenings. Invasive tumours <15mm were 50.4% and 53.8% of the invasive cancers detected in initial and subsequent screenings. Less favourable size, grading and biomarkers expression were found in interval cancers compared to screen-detected cancers. Breast cancer screening programme in the Northern Region of Portugal was well accepted by the population. Most of the performance indicators were consistent with the desirable levels of the European Guidelines, which indicate an effective screening programme. Future research should verify the consistency of some of these results by using updated information from a larger population. Copyright © 2015 Elsevier Ltd. All rights reserved.

Utility of coloured hair for the detection of drugs and alcohol.

PubMed

Agius, Ronald

2014-06-01

The aim of this paper is to assess the utility of coloured hair for the detection of drugs and alcohol in a large statistically significant population. The positivity rate, the 1st, 5th, 50th, 95th, and 99th percentiles of five amphetamines, cannabinoids, cocaine, four opiates, methadone, buprenorphine, seven benzodiazepines, and ethyl glucuronide (EtG) in 9488 non-treated and 1026 cosmetically treated (dyed or bleached) authentic hair samples was compared. Analytical methods used were accredited for forensic purposes at the cut-offs defined by the German driving licence re-granting medical and psychological assessment (MPA) guidelines. Considering only the drug classes for which at least 10 positive samples were detected, the positivity rate in non-treated hair was highest for alcohol (4.50%; measured using EtG at concentrations ≥ 7 pg/mg hair), followed by THC (2.00%), cocaine (1.75%), and amphetamine (0.59%). While the 1st to 99th percentile range was significantly lower for drugs in treated, compared to non-treated hair, no significant change was observed for EtG. Additionally, no significant difference in the positivity rate was observed between treated hair and non-treated hair for both drugs and EtG. This study is the first attempt to evaluate the influence of cosmetic treatment, mainly dying, on the positivity rate for both drugs and EtG in hair samples submitted routinely for abstinence testing and the first to indicate that dyed and eventually bleached hair is not necessarily useless in detecting drugs and/or alcohol consumption, thus making coloured hair analysis still useful, often being the only possibility to prove such misuse. Copyright © 2014 John Wiley & Sons, Ltd.

Double versus single reading of mammograms in a breast cancer screening programme: a cost-consequence analysis.

PubMed

Posso, Margarita C; Puig, Teresa; Quintana, Ma Jesus; Solà-Roca, Judit; Bonfill, Xavier

2016-09-01

To assess the costs and health-related outcomes of double versus single reading of digital mammograms in a breast cancer screening programme. Based on data from 57,157 digital screening mammograms from women aged 50-69 years, we compared costs, false-positive results, positive predictive value and cancer detection rate using four reading strategies: double reading with and without consensus and arbitration, and single reading with first reader only and second reader only. Four highly trained radiologists read the mammograms. Double reading with consensus and arbitration was 15 % (Euro 334,341) more expensive than single reading with first reader only. False-positive results were more frequent at double reading with consensus and arbitration than at single reading with first reader only (4.5 % and 4.2 %, respectively; p < 0.001). The positive predictive value (9.3 % and 9.1 %; p = 0.812) and cancer detection rate were similar for both reading strategies (4.6 and 4.2 per 1000 screens; p = 0.283). Our results suggest that changing to single reading of mammograms could produce savings in breast cancer screening. Single reading could reduce the frequency of false-positive results without changing the cancer detection rate. These results are not conclusive and cannot be generalized to other contexts with less trained radiologists. • Double reading of digital mammograms is more expensive than single reading. • Compared to single reading, double reading yields a higher proportion of false-positive results. • The cancer detection rate was similar for double and single readings. • Single reading may be a cost-effective strategy in breast cancer screening programmes.

Improving staff response to seizures on the epilepsy monitoring unit with online EEG seizure detection algorithms.

PubMed

Rommens, Nicole; Geertsema, Evelien; Jansen Holleboom, Lisanne; Cox, Fieke; Visser, Gerhard

2018-05-11

User safety and the quality of diagnostics on the epilepsy monitoring unit (EMU) depend on reaction to seizures. Online seizure detection might improve this. While good sensitivity and specificity is reported, the added value above staff response is unclear. We ascertained the added value of two electroencephalograph (EEG) seizure detection algorithms in terms of additional detected seizures or faster detection time. EEG-video seizure recordings of people admitted to an EMU over one year were included, with a maximum of two seizures per subject. All recordings were retrospectively analyzed using Encevis EpiScan and BESA Epilepsy. Detection sensitivity and latency of the algorithms were compared to staff responses. False positive rates were estimated on 30 uninterrupted recordings (roughly 24 h per subject) of consecutive subjects admitted to the EMU. EEG-video recordings used included 188 seizures. The response rate of staff was 67%, of Encevis 67%, and of BESA Epilepsy 65%. Of the 62 seizures missed by staff, 66% were recognized by Encevis and 39% by BESA Epilepsy. The median latency was 31 s (staff), 10 s (Encevis), and 14 s (BESA Epilepsy). After correcting for walking time from the observation room to the subject, both algorithms detected faster than staff in 65% of detected seizures. The full recordings included 617 h of EEG. Encevis had a median false positive rate of 4.9 per 24 h and BESA Epilepsy of 2.1 per 24 h. EEG-video seizure detection algorithms may improve reaction to seizures by improving the total number of seizures detected and the speed of detection. The false positive rate is feasible for use in a clinical situation. Implementation of these algorithms might result in faster diagnostic testing and better observation during seizures. Copyright © 2018. Published by Elsevier Inc.

A Randomized Trial Comparing High Definition Colonoscopy Alone With High Definition Dye Spraying and Electronic Virtual Chromoendoscopy for Detection of Colonic Neoplastic Lesions During IBD Surveillance Colonoscopy.

PubMed

Iacucci, Marietta; Kaplan, Gilaad G; Panaccione, Remo; Akinola, Oluseyi; Lethebe, Brendan Cord; Lowerison, Mark; Leung, Yvette; Novak, Kerri L; Seow, Cynthia H; Urbanski, Stefan; Minoo, Parham; Gui, Xianyong; Ghosh, Subrata

2018-02-01

Dye spraying chromoendoscopy (DCE) is recommended for the detection of colonic neoplastic lesions in inflammatory bowel disease (IBD). The majority of neoplastic lesions are visible endoscopically and therefore targeted biopsies are appropriate for surveillance colonoscopy. To compare three different techniques for surveillance colonoscopy to detect colonic neoplastic lesions in IBD patients: high definition (HD), (DCE), or virtual chromoendoscopy (VCE) using iSCAN image enhanced colonoscopy. A randomized non-inferiority trial was conducted to determine the detection rates of neoplastic lesions in IBD patients with longstanding colitis. Patients with inactive disease were enrolled into three arms of the study. Endoscopic neoplastic lesions were classified by the Paris classification and Kudo pit pattern, then histologically classified by the Vienna classification. A total of 270 patients (55% men; age range 20-77 years, median age 49 years) were assessed by HD (n=90), VCE (n=90), or DCE (n=90). Neoplastic lesion detection rates in the VCE arm was non-inferior to the DCE arm. HD was non-inferior to either DCE or VCE for detection of all neoplastic lesions. In the lesions detected, location at right colon and the Kudo pit pattern were predictive of neoplastic lesions (OR 6.52 (1.98-22.5 and OR 21.50 (8.65-60.10), respectively). In this randomized trial, VCE or HD-WLE is not inferior to dye spraying colonoscopy for detection of colonic neoplastic lesions during surveillance colonoscopy. In fact, in this study HD-WLE alone was sufficient for detection of dysplasia, adenocarcinoma or all neoplastic lesions.

Impact of Immediate Interpretation of Screening Tomosynthesis Mammography on Performance Metrics.

PubMed

Winkler, Nicole S; Freer, Phoebe; Anzai, Yoshimi; Hu, Nan; Stein, Matthew

2018-05-07

This study aimed to compare performance metrics for immediate and delayed batch interpretation of screening tomosynthesis mammograms. This HIPAA compliant study was approved by institutional review board with a waiver of consent. A retrospective analysis of screening performance metrics for tomosynthesis mammograms interpreted in 2015 when mammograms were read immediately was compared to historical controls from 2013 to 2014 when mammograms were batch interpreted after the patient had departed. A total of 5518 screening tomosynthesis mammograms (n = 1212 for batch interpretation and n = 4306 for immediate interpretation) were evaluated. The larger sample size for the latter group reflects a group practice shift to performing tomosynthesis for the majority of patients. Age, breast density, comparison examinations, and high-risk status were compared. An asymptotic proportion test and multivariable analysis were used to compare performance metrics. There was no statistically significant difference in recall or cancer detection rates for the batch interpretation group compared to immediate interpretation group with respective recall rate of 6.5% vs 5.3% = +1.2% (95% confidence interval -0.3 to 2.7%; P = .101) and cancer detection rate of 6.6 vs 7.2 per thousand = -0.6 (95% confidence interval -5.9 to 4.6; P = .825). There was no statistically significant difference in positive predictive values (PPVs) including PPV1 (screening recall), PPV2 (biopsy recommendation), or PPV 3 (biopsy performed) with batch interpretation (10.1%, 42.1%, and 40.0%, respectively) and immediate interpretation (13.6%, 39.2%, and 39.7%, respectively). After adjusting for age, breast density, high-risk status, and comparison mammogram, there was no difference in the odds of being recalled or cancer detection between the two groups. There is no statistically significant difference in interpretation performance metrics for screening tomosynthesis mammograms interpreted immediately compared to those interpreted in a delayed fashion. Copyright © 2018. Published by Elsevier Inc.

A Comparison of the Logistic Regression and Contingency Table Methods for Simultaneous Detection of Uniform and Nonuniform DIF

ERIC Educational Resources Information Center

Guler, Nese; Penfield, Randall D.

2009-01-01

In this study, we investigate the logistic regression (LR), Mantel-Haenszel (MH), and Breslow-Day (BD) procedures for the simultaneous detection of both uniform and nonuniform differential item functioning (DIF). A simulation study was used to assess and compare the Type I error rate and power of a combined decision rule (CDR), which assesses DIF…

Comparison of Automated Processing of Flocked Swabs with Manual Processing of Fiber Swabs for Detection of Nasal Carriage of Staphylococcus aureus▿‡

PubMed Central

Jones, Gillian; Matthews, Roger; Cunningham, Richard; Jenks, Peter

2011-01-01

The sensitivity of automated culture of Staphylococcus aureus from flocked swabs versus that of manual culture of fiber swabs was prospectively compared using nasal swabs from 867 patients. Automated culture from flocked swabs significantly increased the detection rate, by 13.1% for direct culture and 10.2% for enrichment culture. PMID:21525218

Quality of colonoscopy performance among gastroenterology and surgical trainees: a need for common training standards for all trainees?

PubMed

Leyden, J E; Doherty, G A; Hanley, A; McNamara, D A; Shields, C; Leader, M; Murray, F E; Patchett, S E; Harewood, G C

2011-11-01

Cecal intubation and polyp detection rates are objective measures of colonoscopy performance. Minimum cecal intubation rates greater than 90% have been endorsed by the American Society for Gastrointestinal Endoscopy (ASGE) and the Joint Advisory Group (JAG) UK. Performance data for medical and surgical trainee endoscopists are limited, and we used endoscopy quality parameters to compare these two groups. Retrospective review of all single-endoscopist colonoscopies done by gastroenterology and surgical trainees ("registrars," equivalent to fellows, postgraduate year 5) with more than two years' endoscopy experience, in 2006 and 2007 at a single academic medical center. Completion rates and polyp detection rates for endoscopists performing more than 50 colonoscopies during the study period were audited. Colonoscopy withdrawal time was prospectively observed in a representative subset of 140 patients. Among 3079 audited single-endoscopist colonoscopies, seven gastroenterology trainees performed 1998 procedures and six surgery trainees performed 1081. The crude completion rate was 82%, 84% for gastroenterology trainees and 78% for surgery trainees (P < 0.0001). Adjusted for poor bowel preparation quality and obstructing lesions, the completion rate was 89%; 93% for gastroenterology trainees, and 84% for surgical trainees (P < 0.0001). The polyp detection rate was 19% overall, with 21% and 14% for gastroenterology and surgical trainees, respectively (P < 0.0001). The adenoma detection rate in patients over 50 was 12%; gastroenterology trainees 14% and surgical trainees 9% (P = 0.0065). In the prospectively audited procedures, median withdrawal time was greater in the gastroenterology trainee group and polyp detection rates correlated closely with withdrawal time (r = 0.99). The observed disparity in endoscopic performance between surgical and gastroenterology trainees suggests the need for a combined or unitary approach to endoscopy training for specialist medical and surgical trainees. © Georg Thieme Verlag KG Stuttgart · New York.

A novel liquid-phase piezoelectric immunosensor for detecting Schistosoma japonicum circulating antigen.

PubMed

Wen, Zhili; Wang, Shiping; Wu, Zhaoyang; Shen, Guoli

2011-09-01

A new liquid-phase piezoelectric immunosensor (LP-PEIS), which can detect Schistosoma japonicum (Sj) circulating antigens (SjCAg) quantificationally, was developed. The IgG antibodies were purified from the sera of rabbits which had been infected or immunized by Sj and were immobilized on the surface of piezoelectric quartz crystal in LP-PEIS by staphylococcal protein A (SPA). It was used to detect SjCAg in sera of rabbits which had been infected by Sj in order to acquire some optimum conditions for detecting SjCAg. Finally, the LP-PEIS with optimum conditions was used to detect SjCAg in sera of patients who had been infected by Sj, and was compared with sandwich ELISA. A lot of optimum conditions of LP-PEIS for detecting SjCAg had been acquired. In the detection of patients' sera with acute Schistosomiasis, LP-PEIS has higher positive rate (100%) and lower false positive rate (3.0%) than sandwich ELISA (92.8%, 6.0%). However, there were no significant difference between LP-PEIS and sandwich ELISA. LP-PEIS can quantificationally detect SjCAg in patients' sera as well as sandwich ELISA. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Heart rate measurement based on face video sequence

NASA Astrophysics Data System (ADS)

Xu, Fang; Zhou, Qin-Wu; Wu, Peng; Chen, Xing; Yang, Xiaofeng; Yan, Hong-jian

2015-03-01

This paper proposes a new non-contact heart rate measurement method based on photoplethysmography (PPG) theory. With this method we can measure heart rate remotely with a camera and ambient light. We collected video sequences of subjects, and detected remote PPG signals through video sequences. Remote PPG signals were analyzed with two methods, Blind Source Separation Technology (BSST) and Cross Spectral Power Technology (CSPT). BSST is a commonly used method, and CSPT is used for the first time in the study of remote PPG signals in this paper. Both of the methods can acquire heart rate, but compared with BSST, CSPT has clearer physical meaning, and the computational complexity of CSPT is lower than that of BSST. Our work shows that heart rates detected by CSPT method have good consistency with the heart rates measured by a finger clip oximeter. With good accuracy and low computational complexity, the CSPT method has a good prospect for the application in the field of home medical devices and mobile health devices.

Synchronized ovulation for first insemination improves reproductive performance and reduces cost per pregnancy in dairy heifers.

PubMed

Silva, T V; Lima, F S; Thatcher, W W; Santos, J E P

2015-11-01

The objectives were to evaluate the effects of synchronizing estrus and ovulation to implement a timed artificial insemination (AI) at first insemination on reproductive performance and cost per pregnancy in dairy heifers. Six hundred eleven Holsteins heifers at approximately 400 d of age from 3 farms were enrolled in the study. Six days before moving to the breeding pens, heifers were allocated randomly to AI after detected estrus from study d 0 to 84 (CON, n=306), or to timed AI for first AI followed by detected estrus for the remainder of the 84-d study (TAI, n=305). Heifers receiving TAI were enrolled in the 5-d timed AI protocol on study d -6 (d -6, GnRH and a progesterone insert; d -1, PGF2α and insert removal; d 0, PGF2α; d 2, GnRH + AI), and they were allowed to be bred the day before scheduled timed AI if detected in estrus. Starting on study d 0, estrus was detected daily. Heifers in estrus were inseminated on the same morning as detected estrus. Control heifers not inseminated by study d 7 received PGF2α and this treatment was repeated every 2 wk until AI. The study lasted 84 d to allow a period of breeding equivalent to four 21-d estrous cycles. A herd budget accounting for inputs for both treatments was created to determine the cost per pregnancy. Sensitivity analysis compared economic differences between the 2 treatments under different input scenarios when detection of estrus after the first AI varied from 50 to 80%. Interval to first AI was 8 d shorter for TAI than for CON. Pregnancy at first AI did not differ between treatments (CON=58.3 vs. TAI=62.8%). In contrast, TAI increased pregnancy per AI (P/AI) compared with CON in heifers inseminated with sex-sorted semen (CON=31.6 vs. TAI=54.8%). The 21-d cycle insemination rate was greater for TAI (91.4%) than for CON (82.4%), even when evaluated after the first 21 d in the study (CON=68.2 vs. TAI=77.1%). The increased insemination rate improved the 21-d cycle pregnancy rate from 47.9% in CON to 57.2% in TAI heifers. In fact, the hazard of pregnancy was 60% greater for TAI than CON. The increased pregnancy rate in TAI reduced the median days to pregnancy by 12 d (CON=2.0 vs. TAI=14.0) and increased the proportion of pregnant heifers by 6.3 percentage points by study d 84 (CON=85.2 vs. TAI=91.5%). The cost per pregnancy was $17.00 less for TAI than CON. The sensitivity analysis indicated that TAI was economically more advantageous to produce a pregnancy compared with CON. Only when insemination rate after the first 21 d of breeding was very high and P/AI was relatively low did the cost per pregnancy become similar for the 2 treatments. Collectively, inseminating all heifers within 2 d of breeding with the 5-d timed AI protocol maintains P/AI, improves pregnancy rate, and reduces cost per pregnancy compared with insemination after detected estrus. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Manipulation Detection and Preference Alterations in a Choice Blindness Paradigm

PubMed Central

Taya, Fumihiko; Gupta, Swati; Farber, Ilya; Mullette-Gillman, O'Dhaniel A.

2014-01-01

Objectives It is commonly believed that individuals make choices based upon their preferences and have access to the reasons for their choices. Recent studies in several areas suggest that this is not always the case. In choice blindness paradigms, two-alternative forced-choice in which chosen-options are later replaced by the unselected option, individuals often fail to notice replacement of their chosen option, confabulate explanations for why they chose the unselected option, and even show increased preferences for the unselected-but-replaced options immediately after choice (seconds). Although choice blindness has been replicated across a variety of domains, there are numerous outstanding questions. Firstly, we sought to investigate how individual- or trial-factors modulated detection of the manipulations. Secondly, we examined the nature and temporal duration (minutes vs. days) of the preference alterations induced by these manipulations. Methods Participants performed a computerized choice blindness task, selecting the more attractive face between presented pairs of female faces, and providing a typewritten explanation for their choice on half of the trials. Chosen-face cue manipulations were produced on a subset of trials by presenting the unselected face during the choice explanation as if it had been selected. Following all choice trials, participants rated the attractiveness of each face individually, and rated the similarity of each face pair. After approximately two weeks, participants re-rated the attractiveness of each individual face online. Results Participants detected manipulations on only a small proportion of trials, with detections by fewer than half of participants. Detection rates increased with the number of prior detections, and detection rates subsequent to first detection were modulated by the choice certainty. We show clear short-term modulation of preferences in both manipulated and non-manipulated explanation trials compared to choice-only trials (with opposite directions of effect). Preferences were altered in the direction that subjects were led to believe they selected. PMID:25247886

Interplay Between the Temporal Dynamics of the Vaginal Microbiota and Human Papillomavirus Detection

PubMed Central

Brotman, Rebecca M.; Shardell, Michelle D.; Gajer, Pawel; Tracy, J. Kathleen; Zenilman, Jonathan M.; Ravel, Jacques; Gravitt, Patti E.

2014-01-01

Background. We sought to describe the temporal relationship between vaginal microbiota and human papillomavirus (HPV) detection. Methods. Thirty-two reproductive-age women self-collected midvaginal swabs twice weekly for 16 weeks (937 samples). Vaginal bacterial communities were characterized by pyrosequencing of barcoded 16S rRNA genes and clustered into 6 community state types (CSTs). Each swab was tested for 37 HPV types. The effects of CSTs on the rate of transition between HPV-negative and HPV-positive states were assessed using continuous-time Markov models. Results. Participants had an average of 29 samples, with HPV point prevalence between 58%–77%. CST was associated with changes in HPV status (P < .001). Lactobacillus gasseri–dominated CSTs had the fastest HPV remission rate, and a low Lactobacillus community with high proportions of the genera Atopobium (CST IV-B) had the slowest rate compared to L. crispatus–dominated CSTs (adjusted transition rate ratio [aTRR], 4.43, 95% confidence interval [CI], 1.11–17.7; aTRR, 0.33, 95% CI, .12–1.19, respectively). The rate ratio of incident HPV for low Lactobacillus CST IV-A was 1.86 (95% CI, .52–6.74). Conclusions. Vaginal microbiota dominated by L. gasseri was associated with increased clearance of detectable HPV. Frequent longitudinal sampling is necessary for evaluation of the association between HPV detection and dynamic microbiota. PMID:24943724

The use of compressive sensing and peak detection in the reconstruction of microtubules length time series in the process of dynamic instability.

PubMed

Mahrooghy, Majid; Yarahmadian, Shantia; Menon, Vineetha; Rezania, Vahid; Tuszynski, Jack A

2015-10-01

Microtubules (MTs) are intra-cellular cylindrical protein filaments. They exhibit a unique phenomenon of stochastic growth and shrinkage, called dynamic instability. In this paper, we introduce a theoretical framework for applying Compressive Sensing (CS) to the sampled data of the microtubule length in the process of dynamic instability. To reduce data density and reconstruct the original signal with relatively low sampling rates, we have applied CS to experimental MT lament length time series modeled as a Dichotomous Markov Noise (DMN). The results show that using CS along with the wavelet transform significantly reduces the recovery errors comparing in the absence of wavelet transform, especially in the low and the medium sampling rates. In a sampling rate ranging from 0.2 to 0.5, the Root-Mean-Squared Error (RMSE) decreases by approximately 3 times and between 0.5 and 1, RMSE is small. We also apply a peak detection technique to the wavelet coefficients to detect and closely approximate the growth and shrinkage of MTs for computing the essential dynamic instability parameters, i.e., transition frequencies and specially growth and shrinkage rates. The results show that using compressed sensing along with the peak detection technique and wavelet transform in sampling rates reduces the recovery errors for the parameters. Copyright © 2015 Elsevier Ltd. All rights reserved.

Suture marker lesion detection in the colon by self-stabilizing and unmodified capsule endoscopes: pilot study in acute canine models.

PubMed

Filip, Dobromir; Yadid-Pecht, Orly; Muench, Gregory; Mintchev, Martin P; Andrews, Christopher N

2013-02-01

Capsule endoscopy is a noninvasive method for examining the small intestine. Recently, this method has been used to visualize the colon. However, the capsule often tumbles in the wider colon lumen, resulting in potentially missed pathology. In addition, the capsule does not have the ability to distend collapsed segments of the organ. Self-stabilizing capsule endoscopy is a new method of visualizing the colon without tumbling and with the ability to passively distend colon walls. To quantitatively compare the detection rate of intraluminal suture marker lesions for colonoscopy by using a custom-modified, self-stabilizing capsule endoscope (SCE); an unmodified capsule endoscope (CE) of the same brand; and a standard colonoscope. Four mongrel dogs underwent laparotomy and the implantation of 5 to 8 suture markers to approximate colon lesions. Each dog had both capsule endoscopy and self-stabilizing capsule endoscopy, administered consecutively in random order. In each case, the capsule was inserted endoscopically into the proximal lumen of the colon followed by pharmacologically induced colon peristalsis to propel it distally through the colon. Blinded standard colonoscopy was performed by an experienced gastroenterologist after the capsule endoscopies. Experimental study in a live canine model. Four dogs. Laparotomy, capsule endoscopy, colonoscopy. Comparison of the marker detection rate of the SCE to that of the unmodified MiroCam CE and a colonoscope. The average percentages of the marker detection rate for unmodified capsule endoscopy, self-stabilizing capsule endoscopy, and colonoscopy, respectively, were 31.1%, 86%, and 100% (P < .01), with both self-stabilizing capsule endoscopy and colonoscopy performing significantly better than the unmodified capsule endoscopy. Acute canine model, suture markings poorly representative of epithelial polyps, limited number of animals. The proposed self-stabilizing capsule endoscope delivered a significant improvement in detection rates of colon suture markings when compared with the unmodified capsule endoscope. Copyright © 2013 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Characterization of the cell growth analysis for detection of immortal cellular impurities in human mesenchymal stem cells.

PubMed

Kono, Ken; Takada, Nozomi; Yasuda, Satoshi; Sawada, Rumi; Niimi, Shingo; Matsuyama, Akifumi; Sato, Yoji

2015-03-01

The analysis of in vitro cell senescence/growth after serial passaging can be one of ways to show the absence of immortalized cells, which are frequently tumorigenic, in human cell-processed therapeutic products (hCTPs). However, the performance of the cell growth analysis for detection of the immortalized cellular impurities has never been evaluated. In the present study, we examined the growth rates of human mesenchymal stem cells (hMSCs, passage 5 (P = 5)) contaminated with various doses of HeLa cells, and compared with that of hMSCs alone. The growth rates of the contaminated hMSCs were comparable to that of hMSCs alone at P = 5, but significantly increased at P = 6 (0.1% and 0.01% HeLa) or P = 7 (0.001% HeLa) within 30 days. These findings suggest that the cell growth analysis is a simple and sensitive method to detect immortalized cellular impurities in hCTPs derived from human somatic cells. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

Differences in incidence rates and early detection of cancer among non-Hispanic and Hispanic Whites in the United States.

PubMed

Merrill, Ray M; Harris, Jessica D; Merrill, Joseph G

2013-01-01

Our study compared cancer incidence rates and stage distribution between non-Hispanic Whites and Hispanic Whites in the United States between 1992 and 2009. A retrospective cohort study was conducted for the years 1992 through 2009. Data represent 13 registries in the Surveillance, Epidemiology, and End Results Program, which reflect 14% of the total US population. The incidence rates for most cancer sites were significantly higher in non-Hispanic Whites than in Hispanic Whites. Exceptions included cancers of the stomach and liver and, for females only, kidney and renal pelvis and cervix uteri. Overall, cancer incidence in non-Hispanic Whites was 40% greater in males and 34% greater in females as compared with Hispanic Whites. Cancer sites with higher incidence rates among non-Hispanic Whites than Hispanic Whites in 2009 compared with 1992 were melanoma, thyroid cancer, oral cavity and pharynx cancer, lymphoma, urinary bladder cancer, and all cancers combined for males and melanoma, thyroid cancer, cervical cancer, and lung and bronchus cancer for females. However, difference in rates narrowed between the ethnicities for colon and rectal cancer and corpus and uterus cancer. Non-Hispanic Whites tended to have a higher percentage of early staged cancer, with little evidence that disparity between the ethnic groups was narrowing in terms of early detection. However, two exceptions involved liver cancer and thyroid cancer in females. The disparity appeared to widen for lung cancer in males. Cancer incidence rates are generally lower in Hispanic Whites than non-Hispanic Whites. The difference in rates between groups has widened over the study period for many cancer sites, with a few exceptions. Poorer screening practices among Hispanic Whites have tended to persist.

Rapid and improved recovery rate of Mycobacterium tuberculosis in Mycobacteria Growth Indicator Tube combined with solid Löwenstein Jensen medium.

PubMed

Rivera, A B; Tupasi, T E; Grimaldo, E R; Cardano, R C; Co, V M

1997-10-01

Clinical microbiology laboratory with limited resources in a developing country. To determine the recovery rate of Mycobacterium tuberculosis (MTB) in Mycobacteria Growth Indicator Tube (MGIT) combined with Löwenstein Jensen (LJ) culture medium. Stock cultures and reference strains of mycobacteria and clinical specimens were inoculated into MGIT and onto LJ. The combined recovery rate was determined and time to positive culture in each medium was compared. All known stock and reference cultures of mycobacteria grew in both media. MGIT combined with LJ increased the recovery rate from 109 (63.4%) to 122 (70.9%) of 172 clinical specimens. Of those isolated, the yield in MGIT (99.2%) exceeded that in LJ (89.3%). The average day to detection of MTB in MGIT was earlier by 14.2 days compared to LJ (15.7 days vs. 29.9 days). For mycobacteria other than tuberculosis (MOTT), there was little difference in the recovery time, except for M. kansasii where growth in MGIT was earlier by one week and M. triviale where growth in MGIT was detected later than LJ. MGIT is an excellent system for the rapid isolation of mycobacteria. It increases the recovery rate of MTB when combined with LJ.

Rumen clearance rates in relation to the occurrence of alfalfa bloat in cattle. 1. Passage of water-soluble markers.

PubMed

Majak, W; Hall, J W; Rode, L M; Kalnin, C M

1986-06-01

Ruminal chlorophyll and rates of passage of two water-soluble markers were simultaneously determined in cattle with different susceptibilities to alfalfa bloat. The markers showed a slower rate of passage from the rumens of more susceptible cattle where the average half-lives for cobalt-ethylenediaminetetraacetic acid and chromium-ethylenediaminetetraacetic acid were 12 to 17 h. Average half-life of the markers was 8 h in the rumens of the less susceptible animals. In agreement, chloroplast particles in the liquid phase of rumen contents showed greater accumulation in animals susceptible to bloat, but many more observations were required to detect differences in chlorophyll among animals. This was partly due to the unhomogeneous dispersion of chloroplast fragments in the reticulorumen compared with the uniform distribution of the inert markers. Differences in rumen volumes (estimated from the quantity of marker administered and its initial concentration) were detected among animals, but these did not show a relationship to bloat susceptibility. In vitro studies indicated that alfalfa chloroplast particles were not readily degraded by rumen microorganisms. Our results support earlier conclusions on slower rates of salivation for cattle that bloat compared with those that do not.

Tropical small streams are a consistent source of methane

NASA Astrophysics Data System (ADS)

Vihermaa, Leena; Waldron, Susan

2013-04-01

To date only a few studies have quantified diffusive methane emissions from headwater streams therefore the magnitude and seasonal variation of these emissions remain poorly understood. Here we present results from two Western Amazonian small streams (first and second order) in Tambopata National Reserve, Peru. Towards the end of wet season, April-May 2012, the streams were sampled using a static floating chamber to accumulate methane. Samples were drawn from the headspace twice daily over period of four days on three separate occasions. The methane concentrations were analysed using a gas chromatograph and the linear part of concentration increase used to calculate the flux rates. The streams were consistently outgassing methane. The seasonally active first order stream outgassed 6 ±2.4 nmol CH4-C m-2 s-1 and the second order stream 20 ±4.0 nmol CH4-C m-2 s-1. The latter flux rate is comparable to fluxes measured from seasonally flooded Amazonian forest in previous studies. The range measured in our streams is comparable to previous results in temperate streams and the lower end of fluxes observed in some peatland streams. The only other study on Amazonian small streams detected methane fluxes that were 100 times greater than those measured here. Depending on the density of small streams in Amazonian basin and the prevalent flux rate, the fluvial methane fluxes may constitute a significant global warming potential. Upscaling to the Amazon basin, assuming small stream density of 0.2 %, as was found at our field site, and the flux rates detected, yields an annual global warming potential equal to approximately 1.5 Mt of CO2 which is of minor importance compared to aquatic CO2-C flux of 500 Mt yr-1 from the basin. However, if the higher fluxes detected in the previous study were prevalent, the basin wide methane flux could become significant. Further studies are needed to establish the stream density in the Amazon basin and typical methane flux rates.

Flexible heartbeat sensor for wearable device.

PubMed

Kwak, Yeon Hwa; Kim, Wonhyo; Park, Kwang Bum; Kim, Kunnyun; Seo, Sungkyu

2017-08-15

We demonstrate a flexible strain-gauge sensor and its use in a wearable application for heart rate detection. This polymer-based strain-gauge sensor was fabricated using a double-sided fabrication method with polymer and metal, i.e., polyimide and nickel-chrome. The fabrication process for this strain-gauge sensor is compatible with the conventional flexible printed circuit board (FPCB) processes facilitating its commercialization. The fabricated sensor showed a linear relation for an applied normal force of more than 930 kPa, with a minimum detectable force of 6.25Pa. This sensor can also linearly detect a bending radius from 5mm to 100mm. It is a thin, flexible, compact, and inexpensive (for mass production) heart rate detection sensor that is highly sensitive compared to the established optical photoplethysmography (PPG) sensors. It can detect not only the timing of heart pulsation, but also the amplitude or shape of the pulse signal. The proposed strain-gauge sensor can be applicable to various applications for smart devices requiring heartbeat detection. Copyright © 2017 Elsevier B.V. All rights reserved.

A novel approach to detect respiratory phases from pulmonary acoustic signals using normalised power spectral density and fuzzy inference system.

PubMed

Palaniappan, Rajkumar; Sundaraj, Kenneth; Sundaraj, Sebastian; Huliraj, N; Revadi, S S

2016-07-01

Monitoring respiration is important in several medical applications. One such application is respiratory rate monitoring in patients with sleep apnoea. The respiratory rate in patients with sleep apnoea disorder is irregular compared with the controls. Respiratory phase detection is required for a proper monitoring of respiration in patients with sleep apnoea. To develop a model to detect the respiratory phases present in the pulmonary acoustic signals and to evaluate the performance of the model in detecting the respiratory phases. Normalised averaged power spectral density for each frame and change in normalised averaged power spectral density between the adjacent frames were fuzzified and fuzzy rules were formulated. The fuzzy inference system (FIS) was developed with both Mamdani and Sugeno methods. To evaluate the performance of both Mamdani and Sugeno methods, correlation coefficient and root mean square error (RMSE) were calculated. In the correlation coefficient analysis in evaluating the fuzzy model using Mamdani and Sugeno method, the strength of the correlation was found to be r = 0.9892 and r = 0.9964, respectively. The RMSE for Mamdani and Sugeno methods are RMSE = 0.0853 and RMSE = 0.0817, respectively. The correlation coefficient and the RMSE of the proposed fuzzy models in detecting the respiratory phases reveals that Sugeno method performs better compared with the Mamdani method. © 2014 John Wiley & Sons Ltd.

A survey of overall life satisfaction and its association with breast diseases in Chinese women.

PubMed

Bai, Aili; Li, Haixin; Huang, Yubei; Liu, Xueou; Gao, Ying; Wang, Peishan; Dai, Hongji; Song, Fengju; Hao, Xishan; Chen, Kexin

2016-01-01

To investigate the association between overall life satisfaction and healthy lifestyle, knowledge of breast cancer, physical examination, and detection rate of breast cancer and benign breast disease in Chinese women. In a multicentered breast disease screening program in China, we enrolled 33,057 women aged 45-65 years without prior diagnosis of breast cancer. After completing an epidemiological questionnaire, all participants were examined by clinical breast examination, breast ultrasound, and mammography independently. All breast cancer cases and a selected sample of benign breast diseases were confirmed pathologically. Univariate and multivariate odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the association between life satisfaction and lifestyle, knowledge of breast cancer, physical examination, and detection rate of breast diseases. Overall life satisfaction was positively associated with women's healthy lifestyle. Compared with less satisfied women, satisfied women were less likely to be smokers (OR = 0.54; 95% CI: 0.47-0.62), have more exercise (OR = 1.49; 95% CI: 1.26-1.75), eat less fried (OR = 0.60; 95% CI: 0.50-0.71), smoked (OR = 0.54, 95% CI: 0.47-0.63), pickled (OR = 0.66, 95% CI: 0.55-0.79), and grilled (OR = 0.63, 95% CI: 0.54-0.74) foods. Satisfied women were more likely to have knowledge of breast cancer (OR = 1.48, 95% CI: 1.29-1.70), and have regular physical examinations (OR = 1.11, 95% CI: 1.01-1.12). Compared to less satisfied women, we found significantly lower detection rate of benign breast diseases (OR = 0.90, 95% CI: 0.82-0.99), and lower but nonsignificant detection rate of breast cancer (OR = 0.66, 95% CI: 0.35-1.25) in satisfied women. Women with a higher overall life satisfaction are more likely to have healthy lifestyle, knowledge of breast cancer, and regular physical examination, thus resulting in a lower detection rate of breast diseases in screening. © 2015 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Polyp detection rates using magnification with narrow band imaging and white light.

PubMed

Gilani, Nooman; Stipho, Sally; Panetta, James D; Petre, Sorin; Young, Michele A; Ramirez, Francisco C

2015-05-16

To compare the yield of adenomas between narrow band imaging and white light when using high definition/magnification. This prospective, non-randomized comparative study was performed at the endoscopy unit of veteran affairs medical center in Phoenix, Arizona. Consecutive patients undergoing first average risk colorectal cancer screening colonoscopy were selected. Two experienced gastroenterologists performed all the procedures that were blinded to each other's findings. Demographic details were recorded. Data are presented as mean ± SEM. Proportional data were compared using the χ(2) test and means were compared using the Student's t test. Tandem colonoscopy was performed in a sequential and segmental fashion using one of 3 strategies: white light followed by narrow band imaging [Group A: white light (WL) → narrow band imaging (NBI)]; narrow band imaging followed by white light (Group B: NBI → WL) and, white light followed by white light (Group C: WL → WL). Detection rate of missed polyps and adenomas were evaluated in all three groups. Three hundred patients were studied (100 in each Group). Although the total time for the colonoscopy was similar in the 3 groups (23.8 ± 0.7, 22.2 ± 0.5 and 24.1 ± 0.7 min for Groups A, B and C, respectively), it reached statistical significance between Groups B and C (P < 0.05). The cecal intubation time in Groups B and C was longer than for Group A (6.5 ± 0.4 min and 6.5 ± 0.4 min vs 4.9 ± 0.3 min; P < 0.05). The withdrawal time for Groups A and C was longer than Group B (18.9 ± 0.7 min and 17.6 ± 0.6 min vs 15.7 ± 0.4 min; P < 0.05). Overall miss rate for polyps and adenomas detected in three groups during the second look was 18% and 17%, respectively (P = NS). Detection rate for polyps and adenomas after first look with white light was similar irrespective of the light used during the second look (WL → WL: 13.7% for polyps, 12.6% for adenomas; WL → NBI: 14.2% for polyps, 11.3% for adenomas). Miss rate of polyps and adenomas however was significantly higher when NBI was used first (29.3% and 30.3%, respectively; P < 0.05). Most missed adenomas were ≤ 5 mm in size. There was only one advanced neoplasia (defined by size only) missed during the first look. Our data suggest that the tandem nature of the procedure rather than the optical techniques was associated with the detection of additional polyps' and adenomas.

Polyp detection rates using magnification with narrow band imaging and white light

PubMed Central

Gilani, Nooman; Stipho, Sally; Panetta, James D; Petre, Sorin; Young, Michele A; Ramirez, Francisco C

2015-01-01

AIM: To compare the yield of adenomas between narrow band imaging and white light when using high definition/magnification. METHODS: This prospective, non-randomized comparative study was performed at the endoscopy unit of veteran affairs medical center in Phoenix, Arizona. Consecutive patients undergoing first average risk colorectal cancer screening colonoscopy were selected. Two experienced gastroenterologists performed all the procedures that were blinded to each other’s findings. Demographic details were recorded. Data are presented as mean ± SEM. Proportional data were compared using the χ2 test and means were compared using the Student’s t test. Tandem colonoscopy was performed in a sequential and segmental fashion using one of 3 strategies: white light followed by narrow band imaging [Group A: white light (WL) → narrow band imaging (NBI)]; narrow band imaging followed by white light (Group B: NBI → WL) and, white light followed by white light (Group C: WL → WL). Detection rate of missed polyps and adenomas were evaluated in all three groups. RESULTS: Three hundred patients were studied (100 in each Group). Although the total time for the colonoscopy was similar in the 3 groups (23.8 ± 0.7, 22.2 ± 0.5 and 24.1 ± 0.7 min for Groups A, B and C, respectively), it reached statistical significance between Groups B and C (P < 0.05). The cecal intubation time in Groups B and C was longer than for Group A (6.5 ± 0.4 min and 6.5 ± 0.4 min vs 4.9 ± 0.3 min; P < 0.05). The withdrawal time for Groups A and C was longer than Group B (18.9 ± 0.7 min and 17.6 ± 0.6 min vs 15.7 ± 0.4 min; P < 0.05). Overall miss rate for polyps and adenomas detected in three groups during the second look was 18% and 17%, respectively (P = NS). Detection rate for polyps and adenomas after first look with white light was similar irrespective of the light used during the second look (WL → WL: 13.7% for polyps, 12.6% for adenomas; WL → NBI: 14.2% for polyps, 11.3% for adenomas). Miss rate of polyps and adenomas however was significantly higher when NBI was used first (29.3% and 30.3%, respectively; P < 0.05). Most missed adenomas were ≤ 5 mm in size. There was only one advanced neoplasia (defined by size only) missed during the first look. CONCLUSION: Our data suggest that the tandem nature of the procedure rather than the optical techniques was associated with the detection of additional polyps’ and adenomas. PMID:25992195

Blinded by the light: on the relationship between CO first overtone emission and mass accretion rate in massive young stellar objects

NASA Astrophysics Data System (ADS)

Ilee, J. D.; Oudmaijer, R. D.; Wheelwright, H. E.; Pomohaci, R.

2018-07-01

To date, there is no explanation as to why disc-tracing CO first overtone (or `bandhead') emission is not a ubiquitous feature in low- to medium-resolution spectra of massive young stellar objects (MYSOs), but instead is only detected towards approximately 25 per cent of their spectra. In this paper, we investigate the hypothesis that only certain mass accretion rates result in detectable bandhead emission in the near-infrared spectra of MYSOs. Using an analytic disc model combined with an LTE model of the CO emission, we find that high accretion rates (≳10-4 M⊙ yr-1) result in large dust sublimation radii, a larger contribution to the K-band continuum from hot dust at the dust sublimation radius, and therefore correspondingly lower CO emission with respect to the continuum. On the other hand, low accretion rates (≲10-6 M⊙ yr-1) result in smaller dust sublimation radii, a correspondingly smaller emitting area of CO, and thus also lower CO emission with respect to the continuum. In general, moderate accretion rates produce the most prominent, and therefore detectable, CO first overtone emission. We compare our findings to a recent near-infrared spectroscopic survey of MYSOs, finding results consistent with our hypothesis. We conclude that the detection rate of CO bandhead emission in the spectra of MYSOs could be the result of MYSOs exhibiting a range of mass accretion rates, perhaps due to the variable accretion suggested by recent multi-epoch observations of these objects.

Blinded by the light: on the relationship between CO first overtone emission and mass accretion rate in massive young stellar objects

NASA Astrophysics Data System (ADS)

Ilee, J. D.; Oudmaijer, R. D.; Wheelwright, H. E.; Pomohaci, R.

2018-04-01

To date, there is no explanation as to why disc-tracing CO first overtone (or `bandhead') emission is not a ubiquitous feature in low- to medium-resolution spectra of massive young stellar objects, but instead is only detected toward approximately 25 per cent of their spectra. In this paper, we investigate the hypothesis that only certain mass accretion rates result in detectable bandhead emission in the near infrared spectra of MYSOs. Using an analytic disc model combined with an LTE model of the CO emission, we find that high accretion rates (≳ 10-4 M⊙yr-1) result in large dust sublimation radii, a larger contribution to the K-band continuum from hot dust at the dust sublimation radius, and therefore correspondingly lower CO emission with respect to the continuum. On the other hand, low accretion rates (≲ 10-6 M⊙yr-1) result in smaller dust sublimation radii, a correspondingly smaller emitting area of CO, and thus also lower CO emission with respect to the continuum. In general, moderate accretion rates produce the most prominent, and therefore detectable, CO first overtone emission. We compare our findings to a recent near-infrared spectroscopic survey of MYSOs, finding results consistent with our hypothesis. We conclude that the detection rate of CO bandhead emission in the spectra of MYSOs could be the result of MYSOs exhibiting a range of mass accretion rates, perhaps due to the variable accretion suggested by recent multi-epoch observations of these objects.

Earthquake Fingerprints: Representing Earthquake Waveforms for Similarity-Based Detection

NASA Astrophysics Data System (ADS)

Bergen, K.; Beroza, G. C.

2016-12-01

New earthquake detection methods, such as Fingerprint and Similarity Thresholding (FAST), use fast approximate similarity search to identify similar waveforms in long-duration data without templates (Yoon et al. 2015). These methods have two key components: fingerprint extraction and an efficient search algorithm. Fingerprint extraction converts waveforms into fingerprints, compact signatures that represent short-duration waveforms for identification and search. Earthquakes are detected using an efficient indexing and search scheme, such as locality-sensitive hashing, that identifies similar waveforms in a fingerprint database. The quality of the search results, and thus the earthquake detection results, is strongly dependent on the fingerprinting scheme. Fingerprint extraction should map similar earthquake waveforms to similar waveform fingerprints to ensure a high detection rate, even under additive noise and small distortions. Additionally, fingerprints corresponding to noise intervals should have mutually dissimilar fingerprints to minimize false detections. In this work, we compare the performance of multiple fingerprint extraction approaches for the earthquake waveform similarity search problem. We apply existing audio fingerprinting (used in content-based audio identification systems) and time series indexing techniques and present modified versions that are specifically adapted for seismic data. We also explore data-driven fingerprinting approaches that can take advantage of labeled or unlabeled waveform data. For each fingerprinting approach we measure its ability to identify similar waveforms in a low signal-to-noise setting, and quantify the trade-off between true and false detection rates in the presence of persistent noise sources. We compare the performance using known event waveforms from eight independent stations in the Northern California Seismic Network.

The efficacy of using computer-aided detection (CAD) for detection of breast cancer in mammography screening: a systematic review.

PubMed

Henriksen, Emilie L; Carlsen, Jonathan F; Vejborg, Ilse Mm; Nielsen, Michael B; Lauridsen, Carsten A

2018-01-01

Background Early detection of breast cancer (BC) is crucial in lowering the mortality. Purpose To present an overview of studies concerning computer-aided detection (CAD) in screening mammography for early detection of BC and compare diagnostic accuracy and recall rates (RR) of single reading (SR) with SR + CAD and double reading (DR) with SR + CAD. Material and Methods PRISMA guidelines were used as a review protocol. Articles on clinical trials concerning CAD for detection of BC in a screening population were included. The literature search resulted in 1522 records. A total of 1491 records were excluded by abstract and 18 were excluded by full text reading. A total of 13 articles were included. Results All but two studies from the SR vs. SR + CAD group showed an increased sensitivity and/or cancer detection rate (CDR) when adding CAD. The DR vs. SR + CAD group showed no significant differences in sensitivity and CDR. Adding CAD to SR increased the RR and decreased the specificity in all but one study. For the DR vs. SR + CAD group only one study reported a significant difference in RR. Conclusion All but two studies showed an increase in RR, sensitivity and CDR when adding CAD to SR. Compared to DR no statistically significant differences in sensitivity or CDR were reported. Additional studies based on organized population-based screening programs, with longer follow-up time, high-volume readers, and digital mammography are needed to evaluate the efficacy of CAD.

A controlled comparison of the BacT/ALERT® 3D and VIRTUO™ microbial detection systems.

PubMed

Totty, H; Ullery, M; Spontak, J; Viray, J; Adamik, M; Katzin, B; Dunne, W M; Deol, P

2017-10-01

The performance of the next-generation BacT/ALERT® VIRTUO™ Microbial Detection System (VIRTUO™, bioMérieux Inc., Hazelwood, MO) was compared to the BacT/ALERT® 3D Microbial Detection System (3D, bioMérieux Inc., Durham, NC) using BacT/ALERT® FA Plus (FA Plus), BacT/ALERT® PF Plus (PF Plus), BacT/ALERT® FN Plus (FN Plus), BacT/ALERT® Standard Aerobic (SA), and BacT/ALERT® Standard Anaerobic (SN) blood culture bottles (bioMérieux Inc., Durham, NC). A seeded limit of detection (LoD) study was performed for each bottle type in both systems. The LoD studies demonstrated that both systems were capable of detecting organisms at nearly identical levels [<10 colony-forming units (CFU) per bottle], with no significant difference. Following LoD determination, a seeded study was performed to compare the time to detection (TTD) between the systems using a panel of clinically relevant microorganisms inoculated at or near the LoD with 0, 4, or 10 mL of healthy human blood. VIRTUO™ exhibited a faster TTD by an average of 3.5 h, as well as demonstrated a significantly improved detection rate of 99.9% compared to 98.8% with 3D (p-value <0.05).

A novel method of forceps biopsy improves the diagnosis of proximal biliary malignancies.

PubMed

Kulaksiz, Hasan; Strnad, Pavel; Römpp, Achim; von Figura, Guido; Barth, Thomas; Esposito, Irene; Schirmacher, Peter; Henne-Bruns, Doris; Adler, Guido; Stiehl, Adolf

2011-02-01

Tissue specimen collection represents a cornerstone in diagnosis of proximal biliary tract malignancies offering great specificity, but only limited sensitivity. To improve the tumor detection rate, we developed a new method of forceps biopsy and compared it prospectively with endoscopic transpapillary brush cytology. 43 patients with proximal biliary stenoses, which were suspect for malignancy, undergoing endoscopic retrograde cholangiography were prospectively recruited and subjected to both biopsy [using a double-balloon enteroscopy (DBE) forceps under a guidance of a pusher and guiding catheter with guidewire] and transpapillary brush cytology. The cytological/histological findings were compared with the final clinical diagnosis. 35 out of 43 patients had a malignant disease (33 cholangiocarcinomas, 1 hepatocellular carcinoma, 1 gallbladder carcinoma). The sensitivity of cytology and biopsy in these patients was 49 and 69%, respectively. The method with DBE forceps allowed a pinpoint biopsy of the biliary stenoses. Both methods had 100% specificity, and, when combined, 80% of malignant processes were detected. All patients with non-malignant conditions were correctly assigned by both methods. No clinically relevant complications were observed. The combination of forceps biopsy and transpapillary brush cytology is safe and offers superior detection rates compared to both methods alone, and therefore represents a promising approach in evaluation of proximal biliary tract processes.

Massive Outflows Associated with ATLASGAL Clumps

NASA Astrophysics Data System (ADS)

Yang, A. Y.; Thompson, M. A.; Urquhart, J. S.; Tian, W. W.

2018-03-01

We have undertaken the largest survey for outflows within the Galactic plane using simultaneously observed {}13{CO} and {{{C}}}18{{O}} data. Out of a total of 919 ATLASGAL clumps, 325 have data suitable to identify outflows, and 225 (69% ± 3%) show high-velocity outflows. The clumps with detected outflows show significantly higher clump masses ({M}clump}), bolometric luminosities ({L}bol}), luminosity-to-mass ratios ({L}bol}/{M}clump}), and peak H2 column densities ({N}{{{H}}2}) compared to those without outflows. Outflow activity has been detected within the youngest quiescent clump (i.e., 70 μ {{m}} weak) in this sample, and we find that the outflow detection rate increases with {M}clump}, {L}bol}, {L}bol}/{M}clump}, and {N}{{{H}}2}, approaching 90% in some cases (UC H II regions = 93% ± 3%; masers = 86% ± 4%; HC H II regions = 100%). This high detection rate suggests that outflows are ubiquitous phenomena of massive star formation (MSF). The mean outflow mass entrainment rate implies a mean accretion rate of ∼ {10}-4 {M}ȯ {yr}}-1, in full agreement with the accretion rate predicted by theoretical models of MSF. Outflow properties are tightly correlated with {M}clump}, {L}bol}, and {L}bol}/{M}clump} and show the strongest relation with the bolometric clump luminosity. This suggests that outflows might be driven by the most massive and luminous source within the clump. The correlations are similar for both low-mass and high-mass outflows over 7 orders of magnitude, indicating that they may share a similar outflow mechanism. Outflow energy is comparable to the turbulent energy within the clump; however, we find no evidence that outflows increase the level of clump turbulence as the clumps evolve. This implies that the origin of turbulence within clumps is fixed before the onset of star formation.

Comparative performance of novel self-sampling methods in detecting high-risk human papillomavirus in 30,130 women not attending cervical screening.

PubMed

Bosgraaf, Remko P; Verhoef, Viola M J; Massuger, Leon F A G; Siebers, Albert G; Bulten, Johan; de Kuyper-de Ridder, Gabriëlle M; Meijer, Chris J M; Snijders, Peter J F; Heideman, Daniëlle A M; IntHout, Joanna; van Kemenade, Folkert J; Melchers, Willem J G; Bekkers, Ruud L M

2015-02-01

We determined whether the participation rate for a brush-based cervicovaginal self-sampling device is noninferior to the participation rate for a lavage-based one for testing for hrHPV (high-risk human papillomavirus). Additionally, positivity rates for hrHPV, the detection rates for cervical intraepithelial neoplasia grades 2 and 3 or worse (CIN2+/3+), and user comfort were compared. A total of 35,477 non-responders of the regular cervical screening program aged 33-63 years were invited to participate. Eligible women (n = 30,130) were randomly assigned to receive either a brush-based or a lavage-based device, and a questionnaire for reporting user convenience. Self-sampling responders testing hrHPV-positive were invited for a physician-taken sample for cytology; triage-positive women were referred for colposcopy. A total of 5,218 women participated in the brush-based sampling group (34.6%) and 4809 women in the lavage-based group (31.9%), i.e. an absolute difference of 2.7% (95%CI 1.8-4.2). The hrHPV-positivity rates in the two groups were identical (8.3%, relative risk (RR) 0.99, 95%CI 0.87-1.13). The detection of CIN2+ and CIN3+ in the brush group (2.0% for CIN2+; 1.3% for CIN3+) was similar to that in the lavage group (1.9% for CIN2+; 1.0% for CIN3+) with a cumulative RR of 1.01, 95%CI 0.83-1.24 for CIN2+ and 1.25, 95%CI 0.92-1.70 for CIN3+. The two self-sampling devices performed similarly in user comfort. In conclusion, offering a brush-based device to non-responders is noninferior to offering a lavage-based device in terms of participation. The two self-sampling methods are equally effective in detecting hrHPV, CIN2+/CIN3+ and are both well accepted. © 2014 UICC.

A Comparison of Grizzly Bear Demographic Parameters Estimated from Non-Spatial and Spatial Open Population Capture-Recapture Models.

PubMed

Whittington, Jesse; Sawaya, Michael A

2015-01-01

Capture-recapture studies are frequently used to monitor the status and trends of wildlife populations. Detection histories from individual animals are used to estimate probability of detection and abundance or density. The accuracy of abundance and density estimates depends on the ability to model factors affecting detection probability. Non-spatial capture-recapture models have recently evolved into spatial capture-recapture models that directly include the effect of distances between an animal's home range centre and trap locations on detection probability. Most studies comparing non-spatial and spatial capture-recapture biases focussed on single year models and no studies have compared the accuracy of demographic parameter estimates from open population models. We applied open population non-spatial and spatial capture-recapture models to three years of grizzly bear DNA-based data from Banff National Park and simulated data sets. The two models produced similar estimates of grizzly bear apparent survival, per capita recruitment, and population growth rates but the spatial capture-recapture models had better fit. Simulations showed that spatial capture-recapture models produced more accurate parameter estimates with better credible interval coverage than non-spatial capture-recapture models. Non-spatial capture-recapture models produced negatively biased estimates of apparent survival and positively biased estimates of per capita recruitment. The spatial capture-recapture grizzly bear population growth rates and 95% highest posterior density averaged across the three years were 0.925 (0.786-1.071) for females, 0.844 (0.703-0.975) for males, and 0.882 (0.779-0.981) for females and males combined. The non-spatial capture-recapture population growth rates were 0.894 (0.758-1.024) for females, 0.825 (0.700-0.948) for males, and 0.863 (0.771-0.957) for both sexes. The combination of low densities, low reproductive rates, and predominantly negative population growth rates suggest that Banff National Park's population of grizzly bears requires continued conservation-oriented management actions.

Trans-rectal ultrasound visibility of prostate lesions identified by magnetic resonance imaging increases accuracy of image-fusion targeted biopsies.

PubMed

Ukimura, Osamu; Marien, Arnaud; Palmer, Suzanne; Villers, Arnauld; Aron, Manju; de Castro Abreu, Andre Luis; Leslie, Scott; Shoji, Sunao; Matsugasumi, Toru; Gross, Mitchell; Dasgupta, Prokar; Gill, Inderbir S

2015-11-01

To compare the diagnostic yield of targeted prostate biopsy using image-fusion of multi-parametric magnetic resonance (mp-MR) with real-time trans-rectal ultrasound (TRUS) for clinically significant lesions that are suspicious only on mp-MR versus lesions that are suspicious on both mp-MR and TRUS. Pre-biopsy MRI and TRUS were each scaled on a 3-point score: highly suspicious, likely, and unlikely for clinically significant cancer (sPCa). Using an MR-TRUS elastic image-fusion system (Koelis), a 127 consecutive patients with a suspicious clinically significant index lesion on pre-biopsy mp-MR underwent systematic biopsies and MR/US-fusion targeted biopsies (01/2010-09/2013). Biopsy histological outcomes were retrospectively compared with MR suspicion level and TRUS-visibility of the MR-suspicious lesion. sPCa was defined as biopsy Gleason score ≥7 and/or maximum cancer core length ≥5 mm. Targeted biopsies outperformed systematic biopsies in overall cancer detection rate (61 vs. 41 %; p = 0.007), sPCa detection rate (43 vs. 23 %; p = 0.0013), cancer core length (7.5 vs. 3.9 mm; p = 0.0002), and cancer rate per core (56 vs. 12 %; p < 0.0001), respectively. Highly suspicious lesions on mp-MR correlated with higher positive biopsy rate (p < 0.0001), higher Gleason score (p = 0.018), and greater cancer core length (p < 0.0001). Highly suspicious lesions on TRUS in corresponding to MR-suspicious lesion had a higher biopsy yield (p < 0.0001) and higher sPCa detection rate (p < 0.0001). Since majority of MR-suspicious lesions were also suspicious on TRUS, TRUS-visibility allowed selection of the specific MR-visible lesion which should be targeted from among the multiple TRUS suspicious lesions in each prostate. MR-TRUS fusion-image-guided biopsies outperformed systematic biopsies. TRUS-visibility of a MR-suspicious lesion facilitates image-guided biopsies, resulting in higher detection of significant cancer.

Projected future impact of HPV vaccination and primary HPV screening on cervical cancer rates from 2017–2035: Example from Australia

PubMed Central

Smith, Megan A.; Saville, Marion; Canfell, Karen

2018-01-01

Background Many countries are transitioning from cytology-based to longer-interval HPV screening. Trials comparing HPV-based screening to cytology report an increase in CIN2/3 detection at the first screen, and longer-term reductions in CIN3+; however, population level year-to-year transitional impacts are poorly understood. We undertook a comprehensive evaluation of switching to longer-interval primary HPV screening in the context of HPV vaccination. We used Australia as an example setting, since Australia will make this transition in December 2017. Methods Using a model of HPV vaccination, transmission, natural history and cervical screening, Policy1-Cervix, we simulated the planned transition from recommending cytology every two years for sexually-active women aged 18–20 to 69, to recommending HPV screening every five years for women aged 25–74 years. We estimated rates of CIN2/3, cervical cancer incidence, and mortality for each year from 2005 to 2035, considering ranges for HPV test accuracy and screening compliance in the context of HPV vaccination (current coverage ~82% in females; ~76% in males). Findings Transient increases are predicted to occur in rates of CIN2/3 detection and invasive cervical cancer in the first two to three years following the screening transition (of 16–24% and 11–14% in respectively, compared to 2017 rates). However, by 2035, CIN2/3 and invasive cervical cancer rates are predicted to fall by 40–44% and 42–51%, respectively, compared to 2017 rates. Cervical cancer mortality rates are predicted to remain unchanged until ~2020, then decline by 34–45% by 2035. Over the period 2018–2035, switching to primary HPV screening in Australia is expected to avert 2,006 cases of invasive cervical cancer and save 587 lives. Conclusions Transient increases in detected CIN2/3 and invasive cancer, which may be detectable at the population level, are predicted following a change to primary HPV screening. This is due to improved test sensitivity bringing forward diagnoses, resulting in longer term reductions in both cervical cancer incidence and mortality. Fluctuations in health outcomes due to the transition to a longer screening interval are predicted to occur for 10–15 years, but cervical cancer rates will be significantly reduced thereafter due to the impact of HPV vaccination and HPV screening. In order to maintain confidence in primary HPV screening through the transitional phase, it is important to widely communicate that an initial increase in CIN2/3 and perhaps even invasive cervical cancer is expected after a national transition to primary HPV screening, that this phenomenon is due to increased prevalent disease detection, and that this effect represents a marker of screening success. PMID:29444073

Towards multimodal detection of melanoma thickness based on optical coherence tomography and optoacoustics

NASA Astrophysics Data System (ADS)

Rahlves, M.; Varkentin, A.; Stritzel, J.; Blumenröther, E.; Mazurenka, M.; Wollweber, M.; Roth, B.

2016-03-01

Melanoma skin cancer has one of the highest mortality rates of all types of cancer if not detected at an early stage. The survival rate is highly dependent on its penetration depth, which is commonly determined by histopathology. In this work, we aim at combining optical coherence tomography and optoacoustic as a non-invasive all-optical method to measure the penetration depth of melanoma. We present our recent achievements to setup a handheld multimodal device and also results from first in vivo measurements on healthy and cancerous skin tissue, which are compared to measurements obtained by ultrasound and histopathology.

First trimester contingent testing with either nuchal translucency or cell-free DNA. Cost efficiency and the role of ultrasound dating.

PubMed

Conner, Peter; Gustafsson, Sven; Kublickas, Marius

2015-04-01

To evaluate the performance and cost efficacy of different first-trimester contingent screening strategies based on an initial analysis of biochemical markers. Retrospective study. Swedish National Quality Register for prenatal diagnosis. 35,780 women with singleton pregnancies. Serum values from first trimester biochemistry were re-analyzed in a contingent approach. For risks between 1:40 and 1:1000, risk estimates from nuchal translucency measurements were added and outcomes were compared using either a final cut-off risk of 1:200 to proceed with invasive testing or offering non-invasive prenatal testing. In a subgroup of 12,836 women with regular menstrual cycles the same analyses were performed using data on the last menstrual period for determining gestational age. The costs of detecting one case of aneuploidy were compared. Comparison of screening strategies. The detection rate was the same (87%) in the contingent group as in complete combined screening, with only 41% requiring a nuchal translucency scan. As an alternative, offering non-invasive prenatal testing to the intermediate risk group would result in a detection rate of 98%, but the cost to detect one case of trisomy 21 would be 83% higher than the cost associated with traditional combined screening. First trimester examination using a contingent approach will achieve similar results compared with full combined screening. Non-invasive prenatal testing will not be cost-effective when a high proportion of pregnancies need further testing. © 2015 Nordic Federation of Societies of Obstetrics and Gynecology.

Item Response Theory as an Efficient Tool to Describe a Heterogeneous Clinical Rating Scale in De Novo Idiopathic Parkinson's Disease Patients.

PubMed

Buatois, Simon; Retout, Sylvie; Frey, Nicolas; Ueckert, Sebastian

2017-10-01

This manuscript aims to precisely describe the natural disease progression of Parkinson's disease (PD) patients and evaluate approaches to increase the drug effect detection power. An item response theory (IRT) longitudinal model was built to describe the natural disease progression of 423 de novo PD patients followed during 48 months while taking into account the heterogeneous nature of the MDS-UPDRS. Clinical trial simulations were then used to compare drug effect detection power from IRT and sum of item scores based analysis under different analysis endpoints and drug effects. The IRT longitudinal model accurately describes the evolution of patients with and without PD medications while estimating different progression rates for the subscales. When comparing analysis methods, the IRT-based one consistently provided the highest power. IRT is a powerful tool which enables to capture the heterogeneous nature of the MDS-UPDRS.

Polarization-multiplexed rate-adaptive non-binary-quasi-cyclic-LDPC-coded multilevel modulation with coherent detection for optical transport networks.

PubMed

Arabaci, Murat; Djordjevic, Ivan B; Saunders, Ross; Marcoccia, Roberto M

2010-02-01

In order to achieve high-speed transmission over optical transport networks (OTNs) and maximize its throughput, we propose using a rate-adaptive polarization-multiplexed coded multilevel modulation with coherent detection based on component non-binary quasi-cyclic (QC) LDPC codes. Compared to prior-art bit-interleaved LDPC-coded modulation (BI-LDPC-CM) scheme, the proposed non-binary LDPC-coded modulation (NB-LDPC-CM) scheme not only reduces latency due to symbol- instead of bit-level processing but also provides either impressive reduction in computational complexity or striking improvements in coding gain depending on the constellation size. As the paper presents, compared to its prior-art binary counterpart, the proposed NB-LDPC-CM scheme addresses the needs of future OTNs, which are achieving the target BER performance and providing maximum possible throughput both over the entire lifetime of the OTN, better.

Droplet digital polymerase chain reaction (PCR) outperforms real-time PCR in the detection of environmental DNA from an invasive fish species.

PubMed

Doi, Hideyuki; Takahara, Teruhiko; Minamoto, Toshifumi; Matsuhashi, Saeko; Uchii, Kimiko; Yamanaka, Hiroki

2015-05-05

Environmental DNA (eDNA) has been used to investigate species distributions in aquatic ecosystems. Most of these studies use real-time polymerase chain reaction (PCR) to detect eDNA in water; however, PCR amplification is often inhibited by the presence of organic and inorganic matter. In droplet digital PCR (ddPCR), the sample is partitioned into thousands of nanoliter droplets, and PCR inhibition may be reduced by the detection of the end-point of PCR amplification in each droplet, independent of the amplification efficiency. In addition, real-time PCR reagents can affect PCR amplification and consequently alter detection rates. We compared the effectiveness of ddPCR and real-time PCR using two different PCR reagents for the detection of the eDNA from invasive bluegill sunfish, Lepomis macrochirus, in ponds. We found that ddPCR had higher detection rates of bluegill eDNA in pond water than real-time PCR with either of the PCR reagents, especially at low DNA concentrations. Limits of DNA detection, which were tested by spiking the bluegill DNA to DNA extracts from the ponds containing natural inhibitors, found that ddPCR had higher detection rate than real-time PCR. Our results suggest that ddPCR is more resistant to the presence of PCR inhibitors in field samples than real-time PCR. Thus, ddPCR outperforms real-time PCR methods for detecting eDNA to document species distributions in natural habitats, especially in habitats with high concentrations of PCR inhibitors.

Is breast compression associated with breast cancer detection and other early performance measures in a population-based breast cancer screening program?

PubMed

Moshina, Nataliia; Sebuødegård, Sofie; Hofvind, Solveig

2017-06-01

We aimed to investigate early performance measures in a population-based breast cancer screening program stratified by compression force and pressure at the time of mammographic screening examination. Early performance measures included recall rate, rates of screen-detected and interval breast cancers, positive predictive value of recall (PPV), sensitivity, specificity, and histopathologic characteristics of screen-detected and interval breast cancers. Information on 261,641 mammographic examinations from 93,444 subsequently screened women was used for analyses. The study period was 2007-2015. Compression force and pressure were categorized using tertiles as low, medium, or high. χ 2 test, t tests, and test for trend were used to examine differences between early performance measures across categories of compression force and pressure. We applied generalized estimating equations to identify the odds ratios (OR) of screen-detected or interval breast cancer associated with compression force and pressure, adjusting for fibroglandular and/or breast volume and age. The recall rate decreased, while PPV and specificity increased with increasing compression force (p for trend <0.05 for all). The recall rate increased, while rate of screen-detected cancer, PPV, sensitivity, and specificity decreased with increasing compression pressure (p for trend <0.05 for all). High compression pressure was associated with higher odds of interval breast cancer compared with low compression pressure (1.89; 95% CI 1.43-2.48). High compression force and low compression pressure were associated with more favorable early performance measures in the screening program.

Variation in Adenoma Detection Rate and the Lifetime Benefits and Cost of Colorectal Cancer Screening: A Microsimulation Model

PubMed Central

Meester, Reinier G.S.; Doubeni, Chyke A.; Lansdorp-Vogelaar, Iris; Jensen, Christopher D.; van der Meulen, Miriam P.; Levin, Theodore R.; Quinn, Virginia P.; Schottinger, Joanne E.; Zauber, Ann G.; Corley, Douglas A.; van Ballegooijen, Marjolein

2015-01-01

IMPORTANCE Colonoscopy is the most commonly used colorectal cancer screening test in the United States. Its quality, as measured by adenoma detection rates, varies widely between physicians with unknown consequences for the cost and benefits of screening programs. OBJECTIVE To estimate the lifetime benefits, complications and costs of a colonoscopy screening program at different levels of adenoma detection. DESIGN, SETTING and PARTICIPANTS This study used microsimulation modeling with data from a community-based healthcare system on adenoma detection rate variation and cancer risk among 136 physicians and 57,588 patients for 1998–2010. EXPOSURE Using modeling, no screening was compared to screening initiation with colonoscopy according to adenoma detection rate quintiles (averages 15.3, 21.3, 25.6, 30.9, and 38.7%) at ages 50, 60 and 70 with appropriate surveillance of adenoma patients. MAIN OUTCOMES Estimated lifetime colorectal cancer incidence, mortality, number of colonoscopies, complications and costs per 1,000 patients, all discounted at 3% per year and including 95% confidence intervals from multiway probabilistic sensitivity analysis (95%CI). RESULTS In simulation modeling, among unscreened patients, the lifetime risks of colorectal cancer incidence and mortality were 34.2 (95%CI:25.9–43.6) and 13.4 (95%CI:10.0–17.6) per 1,000, respectively. Among screened patients, simulated lifetime incidence decreased with lower to higher adenoma detection rates (quintile 1 versus 5: 26.6, 95%CI:20.0–34.3 versus 12.5, 95%CI:9.3–16.5) as did mortality (5.7, 95%CI:4.2–7.7 versus 2.3, 95%CI:1.7–3.1). Compared to quintile 1, simulated lifetime incidence and mortality were on average 11.4% (95%CI:10.3–11.9) and 12.8% (95%CI:11.1–13.7) lower, respectively, for every 5 percentage-point higher adenoma detection rate. Total colonoscopies and associated complications were higher from quintile 1 (2,777, 95%CI:2,626–2,943 and 6.0, 95%CI:4.0–8.5) to subsequent quintiles (quintile 5: 3,376, 95%CI:3,081–3,681 and 8.9, 95%CI:6.1–12.0). Estimated net screening costs were, however, lower from quintile 1 (US $2.1 million, 95%CI:1.8–2.4) to quintile 5 (US$1.8 million, 95%CI:1.3–2.3) due to averted cancer treatment costs. Results were stable across sensitivity analyses. CONCLUSIONS-RELEVANCE Using microsimulation modeling, we found that higher adenoma detection was associated with lower lifetime colorectal cancer incidence and mortality without higher overall costs. Future research is needed to assess if increasing adenoma detection would be associated with improved patient outcomes. PMID:26080339

Signal processing methodologies for an acoustic fetal heart rate monitor

NASA Technical Reports Server (NTRS)

Pretlow, Robert A., III; Stoughton, John W.

1992-01-01

Research and development is presented of real time signal processing methodologies for the detection of fetal heart tones within a noise-contaminated signal from a passive acoustic sensor. A linear predictor algorithm is utilized for detection of the heart tone event and additional processing derives heart rate. The linear predictor is adaptively 'trained' in a least mean square error sense on generic fetal heart tones recorded from patients. A real time monitor system is described which outputs to a strip chart recorder for plotting the time history of the fetal heart rate. The system is validated in the context of the fetal nonstress test. Comparisons are made with ultrasonic nonstress tests on a series of patients. Comparative data provides favorable indications of the feasibility of the acoustic monitor for clinical use.

Near infrared transillumination compared with radiography to detect and monitor proximal caries: A clinical retrospective study.

PubMed

Abdelaziz, Marwa; Krejci, Ivo; Perneger, Thomas; Feilzer, Albert; Vazquez, Lydia

2018-03-01

To compare near infrared transillumination device, DIAGNOcam (DC) and bitewing radiography (BW) for the detection of proximal caries. This retrospective analysis of DC and BW images of 18 students in dental medicine who had consented to the anonymous use of their dental record. The data included BW and DC images performed for a check-up in 2013, and corresponding follow-up images performed in 2015. Two observers rated 376 proximal surfaces on a 4-level dentin lesion scale and reached a unanimous rating for each surface. Calculated measures of agreement for each assessment method over time provided the reproducibility of the information obtained by each method. Agreement between 2013 and 2015 within each method was excellent (intraclass correlation coefficient, BW: 0.86, DC: 0.90). Agreement between DC and BW was similar for dentin lesion detection, but was low for enamel caries detection; DC detected more enamel caries than BW. Agreement between DC and BW was modest (0.33 in 2013 and 0.36 in 2015), chiefly because DC identified more enamel caries. This study shows that DC is as reliable as BW to detect proximal dentin lesions. DC detects proximal enamel lesions at an earlier stage than BW. DC enables clinicians to differentiate lesions limited to the enamel from lesions that have reached the enamel dentin junction. Regular monitoring with DC should help provide individualized preventive measures and early non-invasive caries management. The early detection of enamel lesions with near infrared transillumination can help clinicians undertake early non invasive treatments to prevent or slow down the progression of initial proximal lesions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Selective sentinel node biopsy after intratumour administration of radiotracer in breast cancer patients treated with neoadjuvant chemotherapy in relation to the level of tumour response.

PubMed

Díaz-Expósito, R; Martí-Bonmatí, L; Burgués, O; Casáns-Tormo, I; Bermejo-de Las Heras, B; Julve-Parreño, A; Caballero-Garate, A

Our objective was to analyse the accuracy of the sentinel node biopsy, taking into consideration the scintigraphy detection rate after the intratumoural administration of the radiopharmaceutical in patients with breast cancer who received neoadjuvant chemotherapy. The study included 60 patients with a diagnosis of invasive breast carcinoma, stage T1-T3, who received treatment with neoadjuvant chemotherapy, and were subsequently subjected to breast surgery and sentinel node biopsy after intra-tumour administration of the radiopharmaceutical. Scintigraphic detection of some sentinel node was achieved in 55/60 patients (91.6%). When those cases that received a second injection of the radiopharmaceutical, performed peri-areolarly due to a lack of tracer migration, were excluded, the detection rate dropped to 70% (42/60). When the detection of sentinel node, or its absence, was compared in those 42 patients, no differences were found with age, laterality-location of the lesion, size pre- and post-neoadjuvant chemotherapy, histological grade, or immunohistochemical profile. There were significant differences when comparing the groups according to the degree of pathological tumour response, both with the Miller-Payne system (non-detection 44.4%-detection 16.7%, p = 0.003) as well as the residual cancer burden (72.2%-28.6%, p<0.01). The scintigraphic detection of the sentinel node after intratumoural administration of the radiopharmaceutical in patients with breast cancer who received neoadjuvant chemotherapy was below the optimal value, and sometimes a further, peri-areolar, injection was necessary, probably in relation to an alteration in the lymphatic drainage pathways. There was a significant inverse relationship between the detection of the sentinel node and level of pathological tumour response. Copyright © 2016 Elsevier España, S.L.U. y SEMNIM. All rights reserved.

Understanding environmental DNA detection probabilities: A case study using a stream-dwelling char Salvelinus fontinalis

USGS Publications Warehouse

Wilcox, Taylor M; Mckelvey, Kevin S.; Young, Michael K.; Sepulveda, Adam; Shepard, Bradley B.; Jane, Stephen F; Whiteley, Andrew R.; Lowe, Winsor H.; Schwartz, Michael K.

2016-01-01

Environmental DNA sampling (eDNA) has emerged as a powerful tool for detecting aquatic animals. Previous research suggests that eDNA methods are substantially more sensitive than traditional sampling. However, the factors influencing eDNA detection and the resulting sampling costs are still not well understood. Here we use multiple experiments to derive independent estimates of eDNA production rates and downstream persistence from brook trout (Salvelinus fontinalis) in streams. We use these estimates to parameterize models comparing the false negative detection rates of eDNA sampling and traditional backpack electrofishing. We find that using the protocols in this study eDNA had reasonable detection probabilities at extremely low animal densities (e.g., probability of detection 0.18 at densities of one fish per stream kilometer) and very high detection probabilities at population-level densities (e.g., probability of detection > 0.99 at densities of ≥ 3 fish per 100 m). This is substantially more sensitive than traditional electrofishing for determining the presence of brook trout and may translate into important cost savings when animals are rare. Our findings are consistent with a growing body of literature showing that eDNA sampling is a powerful tool for the detection of aquatic species, particularly those that are rare and difficult to sample using traditional methods.

Comparisons of GLM and LMA Observations

NASA Astrophysics Data System (ADS)

Thomas, R. J.; Krehbiel, P. R.; Rison, W.; Stanley, M. A.; Attanasio, A.

2017-12-01

Observations from 3-dimensional VHF lightning mapping arrays (LMAs) provide a valuable basis for evaluating the spatial accuracy and detection efficiencies of observations from the recently launched, optical-based Geosynchronous Lightning Mapper (GLM). In this presentation, we describe results of comparing the LMA and GLM observations. First, the observations are compared spatially and temporally at the individual event (pixel) level for sets of individual discharges. For LMA networks in Florida, Colorado, and Oklahoma, the GLM observations are well correlated time-wise with LMA observations but are systematically offset by one- to two pixels ( 10 to 15 or 20 km) in a southwesterly direction from the actual lightning activity. The graphical comparisons show a similar location uncertainty depending on the altitude at which the scattered light is emitted from the parent cloud, due to being observed at slant ranges. Detection efficiencies (DEs) can be accurately determined graphically for intervals where individual flashes in a storm are resolved time-wise, and DEs and false alarm rates can be automated using flash sorting algorithms for overall and/or larger storms. This can be done as a function of flash size and duration, and generally shows high detection rates for larger flashes. Preliminary results during the May 1 2017 ER-2 overflight of Colorado storms indicate decreased detection efficiency if the storm is obscured by an overlying cloud layer.

Lightning on jupiter: rate, energetics, and effects.

PubMed

Lewis, J S

1980-12-19

Voyager data on the optical and radio-frequency detection of lightning discharges in the atmosphere of Jupiter suggest a stroke rate significantly lower than on the earth. The efficiency of conversion of atmospheric convective energy flux into lightning is almost certainly less than on the earth, probably near 10(-7) rather than the terrestrial value of 10(-4). At this level the rate of production of complex organic molecules by lightning and by thunder shock waves is negligible compared to the rates of known photochemical processes for forming colored inorganic solids.

Comparison of Color Fundus Photography, Infrared Fundus Photography, and Optical Coherence Tomography in Detecting Retinal Hamartoma in Patients with Tuberous Sclerosis Complex.

PubMed

Bai, Da-Yong; Wang, Xu; Zhao, Jun-Yang; Li, Li; Gao, Jun; Wang, Ning-Li

2016-05-20

A sensitive method is required to detect retinal hamartomas in patients with tuberous sclerosis complex (TSC). The aim of the present study was to compare the color fundus photography, infrared imaging (IFG), and optical coherence tomography (OCT) in the detection rate of retinal hamartoma in patients with TSC. This study included 11 patients (22 eyes) with TSC, who underwent color fundus photography, IFG, and spectral-domain OCT to detect retinal hamartomas. TSC1 and TSC2RESULTS: The mean age of the 11 patients was 8.0 ± 2.1 years. The mean spherical equivalent was -0.55 ± 1.42 D by autorefraction with cycloplegia. In 11 patients (22 eyes), OCT, infrared fundus photography, and color fundus photography revealed 26, 18, and 9 hamartomas, respectively. The predominant hamartoma was type I (55.6%). All the hamartomas that detected by color fundus photography or IFG can be detected by OCT. Among the methods of color fundus photography, IFG, and OCT, the OCT has higher detection rate for retinal hamartoma in TSC patients; therefore, OCT might be promising for the clinical diagnosis of TSC.

Modelling detection probabilities to evaluate management and control tools for an invasive species

USGS Publications Warehouse

Christy, M.T.; Yackel Adams, A.A.; Rodda, G.H.; Savidge, J.A.; Tyrrell, C.L.

2010-01-01

For most ecologists, detection probability (p) is a nuisance variable that must be modelled to estimate the state variable of interest (i.e. survival, abundance, or occupancy). However, in the realm of invasive species control, the rate of detection and removal is the rate-limiting step for management of this pervasive environmental problem. For strategic planning of an eradication (removal of every individual), one must identify the least likely individual to be removed, and determine the probability of removing it. To evaluate visual searching as a control tool for populations of the invasive brown treesnake Boiga irregularis, we designed a mark-recapture study to evaluate detection probability as a function of time, gender, size, body condition, recent detection history, residency status, searcher team and environmental covariates. We evaluated these factors using 654 captures resulting from visual detections of 117 snakes residing in a 5-ha semi-forested enclosure on Guam, fenced to prevent immigration and emigration of snakes but not their prey. Visual detection probability was low overall (= 0??07 per occasion) but reached 0??18 under optimal circumstances. Our results supported sex-specific differences in detectability that were a quadratic function of size, with both small and large females having lower detection probabilities than males of those sizes. There was strong evidence for individual periodic changes in detectability of a few days duration, roughly doubling detection probability (comparing peak to non-elevated detections). Snakes in poor body condition had estimated mean detection probabilities greater than snakes with high body condition. Search teams with high average detection rates exhibited detection probabilities about twice that of search teams with low average detection rates. Surveys conducted with bright moonlight and strong wind gusts exhibited moderately decreased probabilities of detecting snakes. Synthesis and applications. By emphasizing and modelling detection probabilities, we now know: (i) that eradication of this species by searching is possible, (ii) how much searching effort would be required, (iii) under what environmental conditions searching would be most efficient, and (iv) several factors that are likely to modulate this quantification when searching is applied to new areas. The same approach can be use for evaluation of any control technology or population monitoring programme. ?? 2009 The Authors. Journal compilation ?? 2009 British Ecological Society.

Sonography for diagnosis of benign and malignant tumors of the nose and paranasal sinuses.

PubMed

Liu, Jun-jie; Gao, Yong; Wu, Ya-Fei; Zhu, Shang-Yong

2014-09-01

The purpose of this study was to demonstrate the reliability of sonography for diagnosis of nose and paranasal sinus tumors. Ninety-six consecutive patients with tumors underwent sonography and computed tomography (CT) before surgical treatment. Tumor detectability and imaging findings were evaluated independently and then compared with pathologic findings. Of 96 tumors, 75 were detected by sonography, for a detectability rate of 78.1%; 93 tumors were detected by CT, for a detectability rate of 96.9%. By comparison, sonography showed a trend toward higher detectability of nasal vestibular tumors than CT (87.5% for sonography versus 50.0% for CT) and small lumps on the wing of the nose (78.8% for sonography versus 33.3% for CT). Among the sonographic features, boundary, shape, internal echo, calcification, bone invasion, vascular pattern, and cervical lymph node metastasis all had significantly positive correlations with malignancy (P < .05), but size did not (P = .324). In addition, the vascular resistive index for malignant tumors was significantly higher (mean ± SD, 0.66 ± 0.20) than the index for benign lesions (0.24 ± 0.30; P < .001). Moreover, the detection rate for grade 1-3 (small-large) blood flow in benign lesions was only 43.8%, whereas the rate for malignant tumors was 97.7% (P < .001). The vascular pattern may be a promising predictive indicator for distinguishing benign and malignant tumors of the nose and paranasal sinuses. Consequently, sonography has high value for diagnosis of benign and malignant tumors of the nose and paranasal sinuses, especially for nasal vestibular tumors and small lumps on the wing of the nose. © 2014 by the American Institute of Ultrasound in Medicine.

The association between cecal insertion time and colorectal neoplasm detection

PubMed Central

2013-01-01

Background Information on the impact of cecal insertion time on colorectal neoplasm detection is limited. Our objective was to determine the association between cecal insertion time and colorectal neoplasm detection rate in colonoscopy screening. Methods We performed a cross-sectional study of 12,679 consecutive subjects aged 40–79 years undergoing screening colonoscopy in routine health check-ups at the Center for Health Promotion of the Samsung Medical Center from December 2007 to June 2009. Fixed effects logistic regression conditioning on colonoscopist was used to eliminate confounding due to differences in technical ability and other characteristics across colonoscopists. Results The mean cecal insertion time was 5.9 (SD, 4.4 minutes). We identified 4,249 (33.5%) participants with colorectal neoplasms, of whom 1,956 had small single adenomas (<5 mm), 595 had medium single adenomas (5–9 mm), and 1,699 had multiple adenomas or advanced colorectal neoplasms. The overall rates of colorectal neoplasm detection by quartiles of cecal insertion time were 36.8%, 33.4%, 32.7%, and 31.0%, respectively (p trend <0.001).The odds for small single colorectal adenoma detection was 16% lower (adjusted OR 0.84; 95% CI 0.71 to 0.99) in the fourth compared to the first quartile of insertion time (p trend 0.005). Insertion time was not associated with the detection rate of single adenomas ≥5 mm, multiple adenomas or advanced colorectal neoplasms. Conclusion Shorter insertion times were associated with increased rates of detection of small colorectal adenomas <5 mm. Cecal insertion time may be clinically relevant as missed small colorectal adenomas may progress to more advanced lesions. PMID:23915303

An opto-electronic joint detection system based on DSP aiming at early cervical cancer screening

NASA Astrophysics Data System (ADS)

Wang, Weiya; Jia, Mengyu; Gao, Feng; Yang, Lihong; Qu, Pengpeng; Zou, Changping; Liu, Pengxi; Zhao, Huijuan

2015-02-01

The cervical cancer screening at a pre-cancer stage is beneficial to reduce the mortality of women. An opto-electronic joint detection system based on DSP aiming at early cervical cancer screening is introduced in this paper. In this system, three electrodes alternately discharge to the cervical tissue and three light emitting diodes in different wavelengths alternately irradiate the cervical tissue. Then the relative optical reflectance and electrical voltage attenuation curve are obtained by optical and electrical detection, respectively. The system is based on DSP to attain the portable and cheap instrument. By adopting the relative reflectance and the voltage attenuation constant, the classification algorithm based on Support Vector Machine (SVM) discriminates abnormal cervical tissue from normal. We use particle swarm optimization to optimize the two key parameters of SVM, i.e. nuclear factor and cost factor. The clinical data were collected on 313 patients to build a clinical database of tissue responses under optical and electrical stimulations with the histopathologic examination as the gold standard. The classification result shows that the opto-electronic joint detection has higher total coincidence rate than separate optical detection or separate electrical detection. The sensitivity, specificity, and total coincidence rate increase with the increasing of sample numbers in the training set. The average total coincidence rate of the system can reach 85.1% compared with the histopathologic examination.

Improved Detection of Vowel Envelope Frequency Following Responses Using Hotelling's T2 Analysis.

PubMed

Vanheusden, Frederique J; Bell, Steven L; Chesnaye, Michael A; Simpson, David M

2018-05-11

Objective detection of brainstem responses to natural speech stimuli is an important tool for the evaluation of hearing aid fitting, especially in people who may not be able to respond reliably in behavioral tests. Of particular interest is the envelope frequency following response (eFFR), which refers to the EEG response at the stimulus' fundamental frequency (and its harmonics), and here in particular to the response to natural spoken vowel sounds. This article introduces the frequency-domain Hotelling's T (HT2) method for eFFR detection. This method was compared, in terms of sensitivity in detecting eFFRs at the fundamental frequency (HT2_F0), to two different single-channel frequency domain methods (F test on Fourier analyzer (FA) amplitude spectra [FA-F-Test] and magnitude-squared coherence [MSC]) in detecting envelope following responses to natural vowel stimuli in simulated data and EEG data from normal-hearing subjects. Sensitivity was assessed based on the number of detections and the time needed to detect a response for a false-positive rate of 5%. The study also explored whether a single-channel, multifrequency HT2 (HT2_3F) and a multichannel, multifrequency HT2 (HT2_MC) could further improve response detection. Four repeated words were presented sequentially at 70 dB SPL LAeq through ER-2 insert earphones. The stimuli consisted of a prolonged vowel in a /hVd/ structure (where V represents different vowel sounds). Each stimulus was presented over 440 sweeps (220 condensation and 220 rarefaction). EEG data were collected from 12 normal-hearing adult participants. After preprocessing and artifact removal, eFFR detection was compared between the algorithms. For the simulation study, simulated EEG signals were generated by adding random noise at multiple signal to noise ratios (SNRs; 0 to -60dB) to the auditory stimuli as well as to a single sinusoid at the fluctuating and flattened fundamental frequency (f0). For each SNR, 1000 sets of 440 simulated epochs were generated. Performance of the algorithms was assessed based on the number of sets for which a response could be detected at each SNR. In simulation studies, HT2_3F significantly outperformed the other algorithms when detecting a vowel stimulus in noise. For simulations containing responses only at a single frequency, HT2_3F performs worse compared with other approaches applied in this study as the additional frequencies included do not contain additional information. For recorded EEG data, HT2_MC showed a significantly higher response detection rate compared with MSC and FA-F-Test. Both HT2_MC and HT2_F0 also showed a significant reduction in detection time compared with the FA-F-Test algorithm. Comparisons between different electrode locations confirmed a higher number of detections for electrodes close to Cz compared to more peripheral locations. The HT2 method is more sensitive than FA-F-Test and MSC in detecting responses to complex stimuli because it allows detection of multiple frequencies (HT2_F3) and multiple EEG channels (HT2_MC) simultaneously. This effect was shown in simulation studies for HT2_3F and in EEG data for the HT2_MC algorithm. The spread in detection time across subjects is also lower for the HT2 algorithm, with decision on the presence of an eFFR possible within 5 min.

[Stratified sampling survey of major human parasitic diseases in Henan province].

PubMed

Xu, B L; Zhang, H W; Deng, Y; Chen, Z L; Chen, W Q; Lu, D L; Zhang, Y L; Zhao, Y L; Lin, X M; Huang, Q; Yang, C Y; Liu, Y; Zhou, R M; Li, P; Chen, J S; He, L J; Qian, D

2018-03-10

Objective: To understand the prevalence of major human parasitic diseases and related factors in Henan province. Methods: This stratified sampling survey was carried out according to the requirement of national survey protocol of major human parasitic diseases, 2014-2015. The prevalence of soil-transmitted helminths infection, taeniasis and intestinal protozoiasis were surveyed in 104 sites selected from 35 counties (districts) and the prevalence of clonorchiasis was surveyed in 62 sites selected from 37 townships. In each survey spot, 250 persons were surveyed. A total of 26 866 persons and 15 893 persons were surveyed. Modified Kato-Katz thick smear was used to detect the eggs of intestinal helminthes. Tube fecal culture was used to identify the species of hookworm. The Enterobius eggs were detected in children aged 3 to 6 years by using adhesive tape. The cyst and trophozoite of intestinal protozoa were examined with physiological saline direct smear method and iodine stain method. Results: The overall infestation rate of intestinal parasites was2.02% in Henan, and the worm infection rate was higher than protozoa infection rate. Fourteen kinds of intestinal parasites were found, including nematode (5 species), trematode (2 species), and protozoan (7 species). The infection rate of Enterobius vermicularis was highest, and Qinba Mountain ecological area had the highest infestation rate of intestinal parasites in 4 ecological areas of Henan. There was no significant difference in intestinal parasite infection rate between males and females ( χ (2)=3.630, P =0.057), and the differences in intestinal parasite infection rate among different age groups had significance ( χ (2)=124.783, P =0.000 1). The infection rate reached the peak in age group ≤9 years and the major parasite was Enterobius vermicularis . Furthermore the overall human infection rate of parasite showed a downward trend with the increase of educational level of the people ( χ (2)=70.969, P =0.000 1), the differences had significance ( χ (2)=120.118, P =0.000 1). For different populations, the infection rate of intestinal parasites was highest among preschool children. The infection of intestinal helminth was mainly mild, only 2 severe cases were detected. The infection rate of Clonorchis sinensis in urban residents was only 0.006%. Logistic regression analysis showed that being preschool children ( χ (2)=15.765, P =0.000 1) and drinking well water ( χ (2)=45.589, P =0.000 1) were the risk factors for intestinal parasite infection, and annual income per capita of farmers was the protective factor against intestinal parasite infection. The infection rates of protozoa and intestinal parasites decreased sharply compared with the results of previous two surveys, and the rate of intestinal helminth infection also dropped sharply compared with the second survey. The numbers of protozoa, helminth and intestinal parasites detected in this survey were all less than the numbers found in the previous two surveys. Conclusions: Compared the results of three surveys in Henan, the infection rate of protozoa and intestinal parasites showed a downward trend. The prevention and treatment of Enterobius vermicularis infection in children should be the key point of parasitic disease control in the future.

Role of Computer Aided Diagnosis (CAD) in the detection of pulmonary nodules on 64 row multi detector computed tomography

PubMed Central

Prakashini, K; Babu, Satish; Rajgopal, KV; Kokila, K Raja

2016-01-01

Aims and Objectives: To determine the overall performance of an existing CAD algorithm with thin-section computed tomography (CT) in the detection of pulmonary nodules and to evaluate detection sensitivity at a varying range of nodule density, size, and location. Materials and Methods: A cross-sectional prospective study was conducted on 20 patients with 322 suspected nodules who underwent diagnostic chest imaging using 64-row multi-detector CT. The examinations were evaluated on reconstructed images of 1.4 mm thickness and 0.7 mm interval. Detection of pulmonary nodules, initially by a radiologist of 2 years experience (RAD) and later by CAD lung nodule software was assessed. Then, CAD nodule candidates were accepted or rejected accordingly. Detected nodules were classified based on their size, density, and location. The performance of the RAD and CAD system was compared with the gold standard that is true nodules confirmed by consensus of senior RAD and CAD together. The overall sensitivity and false-positive (FP) rate of CAD software was calculated. Observations and Results: Of the 322 suspected nodules, 221 were classified as true nodules on the consensus of senior RAD and CAD together. Of the true nodules, the RAD detected 206 (93.2%) and 202 (91.4%) by the CAD. CAD and RAD together picked up more number of nodules than either CAD or RAD alone. Overall sensitivity for nodule detection with the CAD program was 91.4%, and FP detection per patient was 5.5%. The CAD showed comparatively higher sensitivity for nodules of size 4–10 mm (93.4%) and nodules in hilar (100%) and central (96.5%) location when compared to RAD's performance. Conclusion: CAD performance was high in detecting pulmonary nodules including the small size and low-density nodules. CAD even with relatively high FP rate, assists and improves RAD's performance as a second reader, especially for nodules located in the central and hilar region and for small nodules by saving RADs time. PMID:27578931

Multiparameter FLAER-based flow cytometry for screening of paroxysmal nocturnal hemoglobinuria enhances detection rates in patients with aplastic anemia.

PubMed

Sachdeva, Man Updesh Singh; Varma, Neelam; Chandra, Dinesh; Bose, Parveen; Malhotra, Pankaj; Varma, Subhash

2015-05-01

Flow cytometry is the gold standard methodology for screening of paroxysmal nocturnal hemoglobinuria. In the last few years, proaerolysin conjugated with fluorescein (FLAER) has become an important component of antibody panel used for the detection of paroxysmal nocturnal hemoglobinuria (PNH) clone. This study aimed to compare PNH clone detection by flow cytometry in the pre-FLAER era versus the FLAER era. This was a retrospective analysis of 4 years and included 1004 individuals screened for PNH clone, either presenting as hemolytic anemia or as aplastic anemia. In the pre-FLAER time period, the RBCs and neutrophils were screened with antibodies against CD55 and CD59. With the introduction of FLAER, neutrophils were screened with FLAER/CD24/CD15 and monocytes with FLAER/CD14/CD33 combination. A comparative analysis was done for detection of PNH clone in aplastic anemia patients versus non-aplastic anemia patients, as well as between pre-FLAER and FLAER era. Out of a total of 1004 individuals, 59 (5.8%) were detected to have PNH clone positivity. The frequency of PNH clone detected in aplastic anemia and non-aplastic anemia groups was 12.02 and 3.36%, respectively. The detection rate of PNH clone increased from 4.5% (32/711) in the pre-FLAER era to 9.2% (27/293) with the introduction of FLAER. However, this increase could be attributed to increased detection of PNH clone in the aplastic anemia group, which showed a significant increase from 8.3 to 18.2% after use of FLAER. In the non-aplastic group, PNH clone was detected with similar frequencies before and after use of FLAER (3.2 versus 3.8%, respectively). Mean PNH clone size was lower in the aplastic anemia group when compared with the non-aplastic group. RBCs always showed a lower clone size than neutrophils. PNH clone on neutrophils and monocytes was however similar. Inclusion of FLAER increases the sensitivity of the test which is especially useful in picking up small PNH clones in patients of aplastic anemia.

Detection of influenza-like illness aberrations by directly monitoring Pearson residuals of fitted negative binomial regression models.

PubMed

Chan, Ta-Chien; Teng, Yung-Chu; Hwang, Jing-Shiang

2015-02-21

Emerging novel influenza outbreaks have increasingly been a threat to the public and a major concern of public health departments. Real-time data in seamless surveillance systems such as health insurance claims data for influenza-like illnesses (ILI) are ready for analysis, making it highly desirable to develop practical techniques to analyze such readymade data for outbreak detection so that the public can receive timely influenza epidemic warnings. This study proposes a simple and effective approach to analyze area-based health insurance claims data including outpatient and emergency department (ED) visits for early detection of any aberrations of ILI. The health insurance claims data during 2004-2009 from a national health insurance research database were used for developing early detection methods. The proposed approach fitted the daily new ILI visits and monitored the Pearson residuals directly for aberration detection. First, negative binomial regression was used for both outpatient and ED visits to adjust for potentially influential factors such as holidays, weekends, seasons, temporal dependence and temperature. Second, if the Pearson residuals exceeded 1.96, aberration signals were issued. The empirical validation of the model was done in 2008 and 2009. In addition, we designed a simulation study to compare the time of outbreak detection, non-detection probability and false alarm rate between the proposed method and modified CUSUM. The model successfully detected the aberrations of 2009 pandemic (H1N1) influenza virus in northern, central and southern Taiwan. The proposed approach was more sensitive in identifying aberrations in ED visits than those in outpatient visits. Simulation studies demonstrated that the proposed approach could detect the aberrations earlier, and with lower non-detection probability and mean false alarm rate in detecting aberrations compared to modified CUSUM methods. The proposed simple approach was able to filter out temporal trends, adjust for temperature, and issue warning signals for the first wave of the influenza epidemic in a timely and accurate manner.

Mammographic findings of women recalled for diagnostic work-up in digital versus screen-film mammography in a population-based screening program.

PubMed

Lipasti, Seppo; Anttila, Ahti; Pamilo, Martti

2010-06-01

Limited information is available concerning differences in the radiological findings of women recalled for diagnostic work-up in digital mammography (DM) versus screen-film mammography (SFM) screening. To compare the radiological findings, their positive predictive values (PPVs) for cancer and other process indicators of DM screening performed by computed radiography (CR) technology and SFM screening in a population-based program. The material consisted of women, 50-59 years of age, who were invited for screening: 30 153 women with DM in 2007-2008 and 32 939 women with SFM in 1999-2000. The attendance rate was 77.7% (23 440) in the DM arm and 83.8% (27 593) in the SFM arm. In the DM arm, 1.71% of those screened (401) and in the SFM arm 1.59% (438) were recalled for further work-up. The images resulting in the recall were classified as: 1) tumor-like mass, 2) parenchymal distortion/asymmetry, 3) calcifications, and 4) combination of mass and calcifications. The distributions of the various radiological findings and their PPVs for cancer were compared in both study groups. The recall rates, cancer detection rates, test specificities, and PPVs of the DM and SFM groups were also compared. Women were recalled for diagnostic work-up most often due to tumor-like mass. It was more common in SFM (1.08% per woman screened) than in DM (0.93%). The second most common finding was parenchymal distortion and asymmetry, more often in DM (0.58%) than in SFM (0.37%). Calcifications were the third most common finding. DM exposed calcifications more often (0.49%) than SFM (0.26%). The PPVs for cancer of the recalls were higher in DM than in SFM in all subgroups of radiological findings. The test specificities were similar (DM 98.9%, SFM 98.8%). Significantly more cancers were detected by DM (cancer detection rate 0.623% per woman screened, n=146) than by SFM (cancer detection rate 0.406% per woman screened, n=112). The PPVs for cancer of all recalls for diagnostic work-up were significantly higher in DM (36%) than in SFM (26%). In DM women were recalled for diagnostic work-up more often for calcifications, parenchymal distortions, and asymmetries than in SFM. In the case of tumor-like masses, more women were recalled in SFM. DM detected more cancers than SFM, and the PPVs for cancer were higher in DM than in SFM in all subgroups of radiological findings.

A colloidal gold nanoparticle-based immunochromatographic test strip for rapid and convenient detection of Staphylococcus aureus.

PubMed

Niu, Kaili; Zheng, Xiaoping; Huang, Chusen; Xul, Kuan; Zhi, Yuan; Shen, Hebai; Jia, Nengqin

2014-07-01

An immunochromatographic test strip using gold nanoparticles-staphylococcus aureus monoclonal antibody conjugates was developed for the rapid and convenient detection of staphylococcus aureus based on a double-antibody sandwich format. The detection limit and the detection rate of this test strip is 10(3) CFU /mL and 98.7%, respectively. It could be used for the rapid detection of staphylococcus aureus in food and the results can be visually identified by the naked eye within 10 min. Compared with conventional bacterial detection methods, this developed immunochromatographic assay based test strip has several advantages including simple, fast, low-cost, favorable sensitivity and specificity, exhibiting a great potential for application in food safety control systems and clinical diagnosis.

Thin NaI(Tl) crystals to enhance the detection sensitivity for molten 241Am sources.

PubMed

Peura, Pauli; Bélanger-Champagne, Camille; Eerola, Paula; Dendooven, Peter; Huhtalo, Eero

2018-04-26

A thin 5-mm NaI(Tl) scintillator detector was tested with the goal of enhancing the detection efficiency of 241 Am gamma and X rays for steelworks operations. The performance of a thin (5 mm) NaI(Tl) detector was compared with a standard 76.2-mm thick NaI(Tl) detector. The 5-mm thick detector crystal results in a 55% smaller background rate at 60 keV compared with the thicker detector, translating into the ability to detect 30% weaker 241 Am sources. For a 5 mm thick and 76.2 mm diameter NaI detector in the ladle car tunnel at Outokumpu Tornio Works, the minimum activity of a molten 241 Am source that can be detected in 5 s with 95% probability is 9 MBq. Copyright © 2018 Elsevier Ltd. All rights reserved.

Non-invasive Self-Care Anemia Detection during Pregnancy Using a Smartphone Camera

NASA Astrophysics Data System (ADS)

Anggraeni, M. D.; Fatoni, A.

2017-02-01

Indonesian maternal mortality rate is the highest in South East Asia. Postpartum hemorrhage is the major causes of maternal mortality in Indonesia. Anemia during pregnancy contributes significantly to postpartum hemorrhage. Early detection of anemia during pregnancy may save mothers from maternal death. This research aim to develop a non-invasive self-care anemia detection based on the palpebral color observation and using a smartphone camera. The color intensity (Red, Green, and Blue) was then measured using a Colorgrab software (Loomatix) and analyzed compared to the hemoglobin concentration of the samples, measured using standard Spectrophotometer method. The result showed that the red color intensity had a high correlation (R2=0.814) with a linear regression of y=14.486x + 50.228. This preliminary study may be used as anemia early detection which more objective compared to visual assessment usually performed.

OBSERVATIONS OF ROTATING RADIO TRANSIENTS WITH THE FIRST STATION OF THE LONG WAVELENGTH ARRAY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Taylor, G. B.; Stovall, K.; McCrackan, M.

2016-11-10

Rotating radio transients (RRATs) are a subclass of pulsars first identified in 2006 that are detected only in searches for single pulses and not through their time averaged emission. Here, we present the results of observations of 19 RRATs using the first station of the Long Wavelength Array (LWA1) at frequencies between 30 and 88 MHz. The RRATs observed here were first detected in higher frequency pulsar surveys. Of the 19 RRATs observed, two sources were detected and their dispersion measures, periods, pulse profiles, and flux densities are reported and compared to previous higher frequency measurements. We find a lowmore » detection rate (11%), which could be a combination of the lower sensitivity of LWA1 compared to higher frequency telescopes, and the result of scattering by the interstellar medium or a spectral turnover.« less

A comparison of traffic estimates of nocturnal flying animals using radar, thermal imaging, and acoustic recording.

PubMed

Horton, Kyle G; Shriver, W Gregory; Buler, Jeffrey J

2015-03-01

There are several remote-sensing tools readily available for the study of nocturnally flying animals (e.g., migrating birds), each possessing unique measurement biases. We used three tools (weather surveillance radar, thermal infrared camera, and acoustic recorder) to measure temporal and spatial patterns of nocturnal traffic estimates of flying animals during the spring and fall of 2011 and 2012 in Lewes, Delaware, USA. Our objective was to compare measures among different technologies to better understand their animal detection biases. For radar and thermal imaging, the greatest observed traffic rate tended to occur at, or shortly after, evening twilight, whereas for the acoustic recorder, peak bird flight-calling activity was observed just prior to morning twilight. Comparing traffic rates during the night for all seasons, we found that mean nightly correlations between acoustics and the other two tools were weakly correlated (thermal infrared camera and acoustics, r = 0.004 ± 0.04 SE, n = 100 nights; radar and acoustics, r = 0.14 ± 0.04 SE, n = 101 nights), but highly variable on an individual nightly basis (range = -0.84 to 0.92, range = -0.73 to 0.94). The mean nightly correlations between traffic rates estimated by radar and by thermal infrared camera during the night were more strongly positively correlated (r = 0.39 ± 0.04 SE, n = 125 nights), but also were highly variable for individual nights (range = -0.76 to 0.98). Through comparison with radar data among numerous height intervals, we determined that flying animal height above the ground influenced thermal imaging positively and flight call detections negatively. Moreover, thermal imaging detections decreased with the presence of cloud cover and increased with mean ground flight speed of animals, whereas acoustic detections showed no relationship with cloud cover presence but did decrease with increased flight speed. We found sampling methods to be positively correlated when comparing mean nightly traffic rates across nights. The strength of these correlations generally increased throughout the night, peaking 2-3 hours before morning twilight. Given the convergence of measures by different tools at this time, we suggest that researchers consider sampling flight activity in the hours before morning twilight when differences due to detection biases among sampling tools appear to be minimized.

Doppler ultrasound monitoring technology.

PubMed

Docker, M F

1993-03-01

Developments in the signal processing of Doppler ultrasound used for the detection of fetal heart rate (FHR) have improved the operation of cardiotocographs. These developments are reviewed and the advantages and disadvantages of the various Doppler and signal processing methods are compared.

ATLAS trigger operations: Upgrades to ``Xmon'' rate prediction system

NASA Astrophysics Data System (ADS)

Myers, Ava; Aukerman, Andrew; Hong, Tae Min; Atlas Collaboration

2017-01-01

We present ``Xmon,'' a tool to monitor trigger rates in the Control Room of the ATLAS Experiment. We discuss Xmon's recent (1) updates, (2) upgrades, and (3) operations. (1) Xmon was updated to modify the tool written for the three-level trigger architecture in Run-1 (2009-2012) to adapt to the new two-level system for Run-2 (2015-current). The tool takes as input the beam luminosity to make a rate prediction, which is compared with incoming rates to detect anomalies that occur both globally throughout a run and locally within a run. Global offsets are more commonly caught by the predictions based upon past runs, where offline processing allows for function adjustments and fit quality through outlier rejection. (2) Xmon was upgraded to detect local offsets using on-the-fly predictions, which uses a sliding window of in-run rates to make predictions. (3) Xmon operations examples are given. Future work involves further automation of the steps to provide the predictive functions and for alerting shifters.

Cervical neoplasia and human papilloma virus infection in prostitutes.

PubMed

Gitsch, G; Kainz, C; Reinthaller, A; Kopp, W; Tatra, G; Breitenecker, G

1991-12-01

To evaluate the prevalence and incidence of PAP smears indicating cervical dysplasia as well as human papillomavirus (HPV) infection in prostitutes. Prevalence and incidence study of cervical dysplasia and HPV infection in prostitutes. For detection and typing of HPV-DNA In Situ Hybridisation (ISH) was performed in tissue samples with CIN gained by colposcopically directed punch biopsies. Second Department of Obstetrics and Gynecology, University of Vienna Medical School and STD Clinic of the Public Health Office, Vienna. Registered prostitutes attending the STD Clinic of the Public Health Office and a control group. 978 prostitutes and 5493 women with unknown cytological anamnesis were compared. Frequency of positive PAP smears was significantly higher in prostitutes (6.13% versus 1.43%). To determine the pick-up rate of cervical dysplasia during one year after negative cytology we compared 722 prostitutes and 3162 controls. Prostitutes showed a significant higher dysplasia pick-up rate (3.05% to 1.07%) compared with controls. HPV detection rate in prostitutes was similar to that in the control group. The distribution of HPV types revealed a higher frequency of "high risk" HPV 16/18 and 31/33 in prostitutes. The results demonstrate a higher incidence and prevalence of cervical dysplasia in prostitutes and therefore suggest regular cervical PAP smear screening in registered prostitutes twice a year.

Vitamin K1 versus vitamin K3 for prevention of subclinical vitamin deficiency: a randomized controlled trial.

PubMed

Chawla, D; Deorari, A K; Saxena, R; Paul, V K; Agarwal, R; Biswas, A; Meena, A

2007-11-01

To compare efficacy of intramuscular phytomenadione (fat soluble vitamin K or vitamin K1) with menadione (water soluble vitamin K or vitamin K3) in prevention of subclinical vitamin K deficiency. A doubleblind randomized controlled trial. Tertiary care hospital. Healthy term neonates were randomized to receive 1 mg of either phytomenadione (Group I, n = 85) or menadione (Group II, n = 85) intramuscularly within 2 hours of birth. PIVKA-II, a sensitive and specific marker of vitamin K deficiency was measured by ELISA method (Diagnostica Stago, France). Plasma level > 2 ng/mL was labeled as detectable PIVKA-II. Birth weight (2914 +/- 318 vs 2958 +/- 312 g), gestation (38.4 +/- 1.2 vs 38.4 +/- 1.0 wk) and other baseline variables were comparable between the two groups. 48.2% (41/85) neonates in Group I and 44.7%(38/85) neonates in Group II had detectable PIVKAII levels ([Relative Risk (95% confidence interval): 1.1 (0.8-1.5); P = 0.76]). Median PIVKA-II levels in Group I and Group II were 1.99 ng/mL and 1.97 ng/mL respectively (P = 0.26). At 72 +/- 12 h of age, mean packed cell volume and mean serum bilirubin levels were comparable in the two groups. Comparable PIVKAII detection rate and PIVKAII levels in neonates receiving phytomenadione or menadione indicate their similar efficacy in prevention of vitamin K deficiency. However, high PIVKAII detection rate observed with both preparations indicates recent vitamin K deficiency and may be due to either inadequate dose of vitamin K or persistence of PIVKAII of fetal origin.

Design of a Biorthogonal Wavelet Transform Based R-Peak Detection and Data Compression Scheme for Implantable Cardiac Pacemaker Systems.

PubMed

Kumar, Ashish; Kumar, Manjeet; Komaragiri, Rama

2018-04-19

Bradycardia can be modulated using the cardiac pacemaker, an implantable medical device which sets and balances the patient's cardiac health. The device has been widely used to detect and monitor the patient's heart rate. The data collected hence has the highest authenticity assurance and is convenient for further electric stimulation. In the pacemaker, ECG detector is one of the most important element. The device is available in its new digital form, which is more efficient and accurate in performance with the added advantage of economical power consumption platform. In this work, a joint algorithm based on biorthogonal wavelet transform and run-length encoding (RLE) is proposed for QRS complex detection of the ECG signal and compressing the detected ECG data. Biorthogonal wavelet transform of the input ECG signal is first calculated using a modified demand based filter bank architecture which consists of a series combination of three lowpass filters with a highpass filter. Lowpass and highpass filters are realized using a linear phase structure which reduces the hardware cost of the proposed design approximately by 50%. Then, the location of the R-peak is found by comparing the denoised ECG signal with the threshold value. The proposed R-peak detector achieves the highest sensitivity and positive predictivity of 99.75 and 99.98 respectively with the MIT-BIH arrhythmia database. Also, the proposed R-peak detector achieves a comparatively low data error rate (DER) of 0.002. The use of RLE for the compression of detected ECG data achieves a higher compression ratio (CR) of 17.1. To justify the effectiveness of the proposed algorithm, the results have been compared with the existing methods, like Huffman coding/simple predictor, Huffman coding/adaptive, and slope predictor/fixed length packaging.

Drug screening in medical examiner casework by high-resolution mass spectrometry (UPLC-MSE-TOF).

PubMed

Rosano, Thomas G; Wood, Michelle; Ihenetu, Kenneth; Swift, Thomas A

2013-10-01

Postmortem drug findings yield important analytical evidence in medical examiner casework, and chromatography coupled with nominal mass spectrometry (MS) serves as the predominant general unknown screening approach. We report screening by ultra performance liquid chromatography (UPLC) coupled with hybrid quadrupole time-of-flight mass spectrometer (MS(E)-TOF), with comparison to previously validated nominal mass UPLC-MS and UPLC-MS-MS methods. UPLC-MS(E)-TOF screening for over 950 toxicologically relevant drugs and metabolites was performed in a full-spectrum (m/z 50-1,000) mode using an MS(E) acquisition of both molecular and fragment ion data at low (6 eV) and ramped (10-40 eV) collision energies. Mass error averaged 1.27 ppm for a large panel of reference drugs and metabolites. The limit of detection by UPLC-MS(E)-TOF ranges from 0.5 to 100 ng/mL and compares closely with UPLC-MS-MS. The influence of column recovery and matrix effect on the limit of detection was demonstrated with ion suppression by matrix components correlating closely with early and late eluting reference analytes. Drug and metabolite findings by UPLC-MS(E)-TOF were compared with UPLC-MS and UPLC-MS-MS analyses of postmortem blood in 300 medical examiner cases. Positive findings by all methods totaled 1,528, with a detection rate of 57% by UPLC-MS, 72% by UPLC-MS-MS and 80% by combined UPLC-MS and UPLC-MS-MS screening. Compared with nominal mass screening methods, UPLC-MS(E)-TOF screening resulted in a 99% detection rate and, in addition, offered the potential for the detection of nontargeted analytes via high-resolution acquisition of molecular and fragment ion data.

An evaluation of population index and estimation techniques for tadpoles in desert pools

USGS Publications Warehouse

Jung, Robin E.; Dayton, Gage H.; Williamson, Stephen J.; Sauer, John R.; Droege, Sam

2002-01-01

Using visual (VI) and dip net indices (DI) and double-observer (DOE), removal (RE), and neutral red dye capture-recapture (CRE) estimates, we counted, estimated, and censused Couch's spadefoot (Scaphiopus couchii) and canyon treefrog (Hyla arenicolor) tadpole populations in Big Bend National Park, Texas. Initial dye experiments helped us determine appropriate dye concentrations and exposure times to use in mesocosm and field trials. The mesocosm study revealed higher tadpole detection rates, more accurate population estimates, and lower coefficients of variation among pools compared to those from the field study. In both mesocosm and field studies, CRE was the best method for estimating tadpole populations, followed by DOE and RE. In the field, RE, DI, and VI often underestimated populations in pools with higher tadpole numbers. DI improved with increased sampling. Larger pools supported larger tadpole populations, and tadpole detection rates in general decreased with increasing pool volume and surface area. Hence, pool size influenced bias in tadpole sampling. Across all techniques, tadpole detection rates differed among pools, indicating that sampling bias was inherent and techniques did not consistently sample the same proportion of tadpoles in each pool. Estimating bias (i.e., calculating detection rates) therefore was essential in assessing tadpole abundance. Unlike VI and DOE, DI, RE, and CRE could be used in turbid waters in which tadpoles are not visible. The tadpole population estimates we used accommodated differences in detection probabilities in simple desert pool environments but may not work in more complex habitats.

Compact binary merger rates: Comparison with LIGO/Virgo upper limits

DOE PAGES

Belczynski, Krzysztof; Repetto, Serena; Holz, Daniel E.; ...

2016-03-03

Here, we compare evolutionary predictions of double compact object merger rate densities with initial and forthcoming LIGO/Virgo upper limits. We find that: (i) Due to the cosmological reach of advanced detectors, current conversion methods of population synthesis predictions into merger rate densities are insufficient. (ii) Our optimistic models are a factor of 18 below the initial LIGO/Virgo upper limits for BH–BH systems, indicating that a modest increase in observational sensitivity (by a factor of ~2.5) may bring the first detections or first gravitational wave constraints on binary evolution. (iii) Stellar-origin massive BH–BH mergers should dominate event rates in advanced LIGO/Virgo and can be detected out to redshift z sime 2 with templates including inspiral, merger, and ringdown. Normal stars (more » $$\\lt 150\\;{M}_{\\odot }$$) can produce such mergers with total redshifted mass up to $${M}_{{\\rm{tot,z}}}\\simeq 400\\;{M}_{\\odot }$$. (iv) High black hole (BH) natal kicks can severely limit the formation of massive BH–BH systems (both in isolated binary and in dynamical dense cluster evolution), and thus would eliminate detection of these systems even at full advanced LIGO/Virgo sensitivity. We find that low and high BH natal kicks are allowed by current observational electromagnetic constraints. (v) The majority of our models yield detections of all types of mergers (NS–NS, BH–NS, BH–BH) with advanced detectors. Numerous massive BH–BH merger detections will indicate small (if any) natal kicks for massive BHs.« less

Computerized wheeze detection in young infants: comparison of signals from tracheal and chest wall sensors.

PubMed

Puder, Lia C; Wilitzki, Silke; Bührer, Christoph; Fischer, Hendrik S; Schmalisch, Gerd

2016-12-01

Computerized wheeze detection is an established method for objective assessment of respiratory sounds. In infants, this method has been used to detect subclinical airway obstruction and to monitor treatment effects. The optimal location for the acoustic sensors, however, is unknown. The aim of this study was to evaluate the quality of respiratory sound recordings in young infants, and to determine whether the position of the sensor affected computerized wheeze detection. Respiratory sounds were recorded over the left lateral chest wall and the trachea in 112 sleeping infants (median postmenstrual age: 49 weeks) on 129 test occasions using an automatic wheeze detection device (PulmoTrack ® ). Each recording lasted 10 min and the recordings were stored. A trained clinician retrospectively evaluated the recordings to determine sound quality and disturbances. The wheeze rates of all undisturbed tracheal and chest wall signals were compared using Bland-Altman plots. Comparison of wheeze rates measured over the trachea and the chest wall indicated strong correlation (r  ⩾  0.93, p  <  0.001), with a bias of 1% or less and limits of agreement of within 3% for the inspiratory wheeze rate and within 6% for the expiratory wheeze rate. However, sounds from the chest wall were more often affected by disturbances than sounds from the trachea (23% versus 6%, p  <  0.001). The study suggests that in young infants, a better quality of lung sound recordings can be obtained with the tracheal sensor.

Application of a geographic information system in analyzing the occurrence of atrazine in groundwater of the mid-continental United States

USGS Publications Warehouse

Burkart, M.R.; Kolpin, D.W.

1993-01-01

The US Geological Survey, US Department of Agriculture, and US Environmental Protection Agency are conducting research and regional assessments in support of policy alternatives intended to protect water resources from agricultural chemical contamination. The mid-continent was selected because of the intense row crop agriculture and associated herbicide application in this region. An application of a geographic information system is demonstrated for analyzing and comparing the distribution of estimated atrazine use to the detection rate of atrazine in groundwater. Understanding the relations between atrazine use and detection in groundwater is important in policy deliberations to protect water resources. Relational analyses between measures of chemical use and detection rate by natural resource units may provide insight into critical factors controlling the processes that result in groundwater contamination from agricultural chemicals. 

Improving detection tools for the emerald ash borer (Coleoptera: Buprestidae): comparison of prism and multifunnel traps at varying population densities.

PubMed

Francese, Joseph A; Rietz, Michael L; Crook, Damon J; Fraser, Ivich; Lance, David R; Mastro, Victor C

2013-12-01

The current emerald ash borer survey trap used in the United States is a prism trap constructed from a stock purple corrugated plastic. In recent years, several colors (particularly shades of green and purple) have been shown to be more attractive to the emerald ash borer than this stock color. Our goal was to determine if plastics produced with these colors and incorporated into prism traps can improve and serve as a new alternative to plastics already in use for the emerald ash borer survey. The plastics were tested in moderate to heavily infested areas in Michigan in two initial studies to test their effectiveness at catching the emerald ash borer. Because results from studies performed in heavily infested sites may not always correspond with what is found along the edges of the infestation, we compared trap catch and detection rates (recording at least one catch on a trap over the course of the entire trapping season) of several trap types and colors at sites outside the core of the currently known emerald ash borer infestation in a nine-state detection tool comparison study. Two of the new plastics, a (Sabic) purple and a medium-dark (Sabic) green were incorporated into prism traps and tested alongside a standard purple prism trap and a green multifunnel trap. In areas with lower emerald ash borer density, the new purple (Sabic) corrugated plastic caught more beetles than the current purple prism trap, as well as more than the medium-dark green (Sabic) prism and green multifunnel traps. Sabic purple traps in the detection tools comparison study recorded a detection rate of 86% compared with 73, 66, and 58% for the standard purple, Sabic green, and green multifunnel traps, respectively. These detection rates were reduced to 80, 63, 55, and 46%, respectively, at low emerald ash borer density sites.

Clinical value of combining transvaginal contrast-enhanced ultrasonography with serum human epididymisprotein-4 and the resistance index for early-stage epithelial ovarian cancer

PubMed Central

Meng, Wu; Ying, Wang; Qichao, Zheng; Ping, Li; Jie, Tang

2017-01-01

Objectives: To increase accuracy of the detection and differential diagnosis of the early epithelial ovarian cancer (EOC) with transvaginal contrast-enhanced ultrasonography (TVCEUS) combining serum human epididymisprotein 4 (HE4), and resistance index (RI). Methods: This retrospectively case-control study of 230 patients with ovarian tumors were reviewed at the Department of Gynecology and Obstetrics, Zhongnan Hospital, Wuhan University, Wuhan, China between June 2008 and September 2015. Before the operation of 110 cases with EOC (Group A) and 120 cases of patients with benign ovarian tumor (Group B), we observe and calculate both Groups’ tumor vascular contrast-enhanced ultrasonography morphology scores (U), time-intensity curve (TIC) of contrast-enhanced ultrasonography, HE4, and RI. Results were compared with the histopathological analysis results. Results: The ultrasonography morphology scores, peak intensity (PI) enhancement rate (ER) with the parameters of the TIC and HE4 are higher in Group A compared with patients in Group B and the RI was lower than Group B. The detection rates for all indexes in the benign and malignant groups and their comparisons to the histopathological results were determined. The detection rate differences for HE4 (p=0.001), RI (p=0.001), U (p=0.001), PI (p=0.001), and ER (p=0.001) were all statistically significant (p<0.05). Conclusion: The high clinical value through combined TVCEUS, HE4, and RI detection can increase the sensitivity of the diagnosis and differential diagnosis of the early EOC. PMID:28578437

Scale and Sampling Effects on Floristic Quality

PubMed Central

2016-01-01

Floristic Quality Assessment (FQA) is increasingly influential for making land management decisions, for directing conservation policy, and for research. But, the basic ecological properties and limitations of its metrics are ill defined and not well understood–especially those related to sample methods and scale. Nested plot data from a remnant tallgrass prairie sampled annually over a 12-year period, were used to investigate FQA properties associated with species detection rates, species misidentification rates, sample year, and sample grain/area. Plot size had no apparent effect on Mean C (an area’s average Floristic Quality level), nor did species detection levels above 65% detection. Simulated species misidentifications only affected Mean C values at greater than 10% in large plots, when the replaced species were randomly drawn from the broader county-wide species pool. Finally, FQA values were stable over the 12-year study, meaning that there was no evidence that the metrics exhibit year effects. The FQA metric Mean C is demonstrated to be robust to varied sample methodologies related to sample intensity (plot size, species detection rate), as well as sample year. These results will make FQA measures even more appealing for informing land-use decisions, policy, and research for two reasons: 1) The sampling effort needed to generate accurate and consistent site assessments with FQA measures is shown to be far lower than what has previously been assumed, and 2) the stable properties and consistent performance of metrics with respect to sample methods will allow for a remarkable level of comparability of FQA values from different sites and datasets compared to other commonly used ecological metrics. PMID:27489959

Mortality Among Men with Advanced Prostate Cancer Excluded from the ProtecT Trial.

PubMed

Johnston, Thomas J; Shaw, Greg L; Lamb, Alastair D; Parashar, Deepak; Greenberg, David; Xiong, Tengbin; Edwards, Alison L; Gnanapragasam, Vincent; Holding, Peter; Herbert, Phillipa; Davis, Michael; Mizielinsk, Elizabeth; Lane, J Athene; Oxley, Jon; Robinson, Mary; Mason, Malcolm; Staffurth, John; Bollina, Prasad; Catto, James; Doble, Andrew; Doherty, Alan; Gillatt, David; Kockelbergh, Roger; Kynaston, Howard; Prescott, Steve; Paul, Alan; Powell, Philip; Rosario, Derek; Rowe, Edward; Donovan, Jenny L; Hamdy, Freddie C; Neal, David E

2017-03-01

Early detection and treatment of asymptomatic men with advanced and high-risk prostate cancer (PCa) may improve survival rates. To determine outcomes for men diagnosed with advanced PCa following prostate-specific antigen (PSA) testing who were excluded from the ProtecT randomised trial. Mortality was compared for 492 men followed up for a median of 7.4 yr to a contemporaneous cohort of men from the UK Anglia Cancer Network (ACN) and with a matched subset from the ACN. PCa-specific and all-cause mortality were compared using Kaplan-Meier analysis and Cox's proportional hazards regression. Of the 492 men excluded from the ProtecT cohort, 37 (8%) had metastases (N1, M0=5, M1=32) and 305 had locally advanced disease (62%). The median PSA was 17μg/l. Treatments included radical prostatectomy (RP; n=54; 11%), radiotherapy (RT; n=245; 50%), androgen deprivation therapy (ADT; n=122; 25%), other treatments (n=11; 2%), and unknown (n=60; 12%). There were 49 PCa-specific deaths (10%), of whom 14 men had received radical treatment (5%); and 129 all-cause deaths (26%). In matched ProtecT and ACN cohorts, 37 (9%) and 64 (16%), respectively, died of PCa, while 89 (22%) and 103 (26%) died of all causes. ProtecT men had a 45% lower risk of death from PCa compared to matched cases (hazard ratio 0.55, 95% confidence interval 0.38-0.83; p=0.0037), but mortality was similar in those treated radically. The nonrandomised design is a limitation. Men with PSA-detected advanced PCa excluded from ProtecT and treated radically had low rates of PCa death at 7.4-yr follow-up. Among men who underwent nonradical treatment, the ProtecT group had a lower rate of PCa death. Early detection through PSA testing, leadtime bias, and group heterogeneity are possible factors in this finding. Prostate cancer that has spread outside the prostate gland without causing symptoms can be detected via prostate-specific antigen testing and treated, leading to low rates of death from this disease. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.

Infrared imaging based hyperventilation monitoring through respiration rate estimation

NASA Astrophysics Data System (ADS)

Basu, Anushree; Routray, Aurobinda; Mukherjee, Rashmi; Shit, Suprosanna

2016-07-01

A change in the skin temperature is used as an indicator of physical illness which can be detected through infrared thermography. Thermograms or thermal images can be used as an effective diagnostic tool for monitoring and diagnosis of various diseases. This paper describes an infrared thermography based approach for detecting hyperventilation caused due to stress and anxiety in human beings by computing their respiration rates. The work employs computer vision techniques for tracking the region of interest from thermal video to compute the breath rate. Experiments have been performed on 30 subjects. Corner feature extraction using Minimum Eigenvalue (Shi-Tomasi) algorithm and registration using Kanade Lucas-Tomasi algorithm has been used here. Thermal signature around the extracted region is detected and subsequently filtered through a band pass filter to compute the respiration profile of an individual. If the respiration profile shows unusual pattern and exceeds the threshold we conclude that the person is stressed and tending to hyperventilate. Results obtained are compared with standard contact based methods which have shown significant correlations. It is envisaged that the thermal image based approach not only will help in detecting hyperventilation but can assist in regular stress monitoring as it is non-invasive method.

Indo-Pacific humpback dolphin occurrence north of Lantau Island, Hong Kong, based on year-round passive acoustic monitoring.

PubMed

Munger, Lisa; Lammers, Marc O; Cifuentes, Mattie; Würsig, Bernd; Jefferson, Thomas A; Hung, Samuel K

2016-10-01

Long-term passive acoustic monitoring (PAM) was conducted to study Indo-Pacific humpback dolphins, Sousa chinensis, as part of environmental impact assessments for several major coastal development projects in Hong Kong waters north of Lantau Island. Ecological acoustic recorders obtained 2711 days of recording at 13 sites from December 2012 to December 2014. Humpback dolphin sounds were manually detected on more than half of days with recordings at 12 sites, 8 of which were within proposed reclamation areas. Dolphin detection rates were greatest at Lung Kwu Chau, with other high-occurrence locations northeast of the Hong Kong International Airport and within the Lung Kwu Tan and Siu Ho Wan regions. Dolphin detection rates were greatest in summer and autumn (June-November) and were significantly reduced in spring (March-May) compared to other times of year. Click detection rates were significantly higher at night than during daylight hours. These findings suggest high use of many of the proposed reclamation/development areas by humpback dolphins, particularly at night, and demonstrate the value of long-term PAM for documenting spatial and temporal patterns in dolphin occurrence to help inform management decisions.

Vital sign sensing method based on EMD in terahertz band

NASA Astrophysics Data System (ADS)

Xu, Zhengwu; Liu, Tong

2014-12-01

Non-contact respiration and heartbeat rates detection could be applied to find survivors trapped in the disaster or the remote monitoring of the respiration and heartbeat of a patient. This study presents an improved algorithm that extracts the respiration and heartbeat rates of humans by utilizing the terahertz radar, which further lessens the effects of noise, suppresses the cross-term, and enhances the detection accuracy. A human target echo model for the terahertz radar is first presented. Combining the over-sampling method, low-pass filter, and Empirical Mode Decomposition improves the signal-to-noise ratio. The smoothed pseudo Wigner-Ville distribution time-frequency technique and the centroid of the spectrogram are used to estimate the instantaneous velocity of the target's cardiopulmonary motion. The down-sampling method is adopted to prevent serious distortion. Finally, a second time-frequency analysis is applied to the centroid curve to extract the respiration and heartbeat rates of the individual. Simulation results show that compared with the previously presented vital sign sensing method, the improved algorithm enhances the signal-to-noise ratio to 1 dB with a detection accuracy of 80%. The improved algorithm is an effective approach for the detection of respiration and heartbeat signal in a complicated environment.

Use of a Terrestrial LIDAR Sensor for Drift Detection in Vineyard Spraying

PubMed Central

Gil, Emilio; Llorens, Jordi; Llop, Jordi; Fàbregas, Xavier; Gallart, Montserrat

2013-01-01

The use of a scanning Light Detection and Ranging (LIDAR) system to characterize drift during pesticide application is described. The LIDAR system is compared with an ad hoc test bench used to quantify the amount of spray liquid moving beyond the canopy. Two sprayers were used during the field test; a conventional mist blower at two air flow rates (27,507 and 34,959 m3·h−1) equipped with two different nozzle types (conventional and air injection) and a multi row sprayer with individually oriented air outlets. A simple model based on a linear function was used to predict spray deposit using LIDAR measurements and to compare with the deposits measured over the test bench. Results showed differences in the effectiveness of the LIDAR sensor depending on the sprayed droplet size (nozzle type) and air intensity. For conventional mist blower and low air flow rate; the sensor detects a greater number of drift drops obtaining a better correlation (r = 0.91; p < 0.01) than for the case of coarse droplets or high air flow rate. In the case of the multi row sprayer; drift deposition in the test bench was very poor. In general; the use of the LIDAR sensor presents an interesting and easy technique to establish the potential drift of a specific spray situation as an adequate alternative for the evaluation of drift potential. PMID:23282583

Automatic mouse ultrasound detector (A-MUD): A new tool for processing rodent vocalizations

PubMed Central

Reitschmidt, Doris; Noll, Anton; Balazs, Peter; Penn, Dustin J.

2017-01-01

House mice (Mus musculus) emit complex ultrasonic vocalizations (USVs) during social and sexual interactions, which have features similar to bird song (i.e., they are composed of several different types of syllables, uttered in succession over time to form a pattern of sequences). Manually processing complex vocalization data is time-consuming and potentially subjective, and therefore, we developed an algorithm that automatically detects mouse ultrasonic vocalizations (Automatic Mouse Ultrasound Detector or A-MUD). A-MUD is a script that runs on STx acoustic software (S_TOOLS-STx version 4.2.2), which is free for scientific use. This algorithm improved the efficiency of processing USV files, as it was 4–12 times faster than manual segmentation, depending upon the size of the file. We evaluated A-MUD error rates using manually segmented sound files as a ‘gold standard’ reference, and compared them to a commercially available program. A-MUD had lower error rates than the commercial software, as it detected significantly more correct positives, and fewer false positives and false negatives. The errors generated by A-MUD were mainly false negatives, rather than false positives. This study is the first to systematically compare error rates for automatic ultrasonic vocalization detection methods, and A-MUD and subsequent versions will be made available for the scientific community. PMID:28727808

Brain fingerprinting field studies comparing P300-MERMER and P300 brainwave responses in the detection of concealed information.

PubMed

Farwell, Lawrence A; Richardson, Drew C; Richardson, Graham M

2013-08-01

Brain fingerprinting detects concealed information stored in the brain by measuring brainwave responses. We compared P300 and P300-MERMER event-related brain potentials for error rate/accuracy and statistical confidence in four field/real-life studies. 76 tests detected presence or absence of information regarding (1) real-life events including felony crimes; (2) real crimes with substantial consequences (either a judicial outcome, i.e., evidence admitted in court, or a $100,000 reward for beating the test); (3) knowledge unique to FBI agents; and (4) knowledge unique to explosives (EOD/IED) experts. With both P300 and P300-MERMER, error rate was 0 %: determinations were 100 % accurate, no false negatives or false positives; also no indeterminates. Countermeasures had no effect. Median statistical confidence for determinations was 99.9 % with P300-MERMER and 99.6 % with P300. Brain fingerprinting methods and scientific standards for laboratory and field applications are discussed. Major differences in methods that produce different results are identified. Markedly different methods in other studies have produced over 10 times higher error rates and markedly lower statistical confidences than those of these, our previous studies, and independent replications. Data support the hypothesis that accuracy, reliability, and validity depend on following the brain fingerprinting scientific standards outlined herein.

Space moving target detection using time domain feature

NASA Astrophysics Data System (ADS)

Wang, Min; Chen, Jin-yong; Gao, Feng; Zhao, Jin-yu

2018-01-01

The traditional space target detection methods mainly use the spatial characteristics of the star map to detect the targets, which can not make full use of the time domain information. This paper presents a new space moving target detection method based on time domain features. We firstly construct the time spectral data of star map, then analyze the time domain features of the main objects (target, stars and the background) in star maps, finally detect the moving targets using single pulse feature of the time domain signal. The real star map target detection experimental results show that the proposed method can effectively detect the trajectory of moving targets in the star map sequence, and the detection probability achieves 99% when the false alarm rate is about 8×10-5, which outperforms those of compared algorithms.

Continuous detection of weak sensory signals in afferent spike trains: the role of anti-correlated interspike intervals in detection performance.

PubMed

Goense, J B M; Ratnam, R

2003-10-01

An important problem in sensory processing is deciding whether fluctuating neural activity encodes a stimulus or is due to variability in baseline activity. Neurons that subserve detection must examine incoming spike trains continuously, and quickly and reliably differentiate signals from baseline activity. Here we demonstrate that a neural integrator can perform continuous signal detection, with performance exceeding that of trial-based procedures, where spike counts in signal- and baseline windows are compared. The procedure was applied to data from electrosensory afferents of weakly electric fish (Apteronotus leptorhynchus), where weak perturbations generated by small prey add approximately 1 spike to a baseline of approximately 300 spikes s(-1). The hypothetical postsynaptic neuron, modeling an electrosensory lateral line lobe cell, could detect an added spike within 10-15 ms, achieving near ideal detection performance (80-95%) at false alarm rates of 1-2 Hz, while trial-based testing resulted in only 30-35% correct detections at that false alarm rate. The performance improvement was due to anti-correlations in the afferent spike train, which reduced both the amplitude and duration of fluctuations in postsynaptic membrane activity, and so decreased the number of false alarms. Anti-correlations can be exploited to improve detection performance only if there is memory of prior decisions.

Interplay between the temporal dynamics of the vaginal microbiota and human papillomavirus detection.

PubMed

Brotman, Rebecca M; Shardell, Michelle D; Gajer, Pawel; Tracy, J Kathleen; Zenilman, Jonathan M; Ravel, Jacques; Gravitt, Patti E

2014-12-01

We sought to describe the temporal relationship between vaginal microbiota and human papillomavirus (HPV) detection. Thirty-two reproductive-age women self-collected midvaginal swabs twice weekly for 16 weeks (937 samples). Vaginal bacterial communities were characterized by pyrosequencing of barcoded 16S rRNA genes and clustered into 6 community state types (CSTs). Each swab was tested for 37 HPV types. The effects of CSTs on the rate of transition between HPV-negative and HPV-positive states were assessed using continuous-time Markov models. Participants had an average of 29 samples, with HPV point prevalence between 58%-77%. CST was associated with changes in HPV status (P<.001). Lactobacillus gasseri-dominated CSTs had the fastest HPV remission rate, and a low Lactobacillus community with high proportions of the genera Atopobium (CST IV-B) had the slowest rate compared to L. crispatus-dominated CSTs (adjusted transition rate ratio [aTRR], 4.43, 95% confidence interval [CI], 1.11-17.7; aTRR, 0.33, 95% CI, .12-1.19, respectively). The rate ratio of incident HPV for low Lactobacillus CST IV-A was 1.86 (95% CI, .52-6.74). Vaginal microbiota dominated by L. gasseri was associated with increased clearance of detectable HPV. Frequent longitudinal sampling is necessary for evaluation of the association between HPV detection and dynamic microbiota. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Comparison of gadobenate dimeglumine-enhanced breast MRI and gadopentetate dimeglumine-enhanced breast MRI with mammography and ultrasound for the detection of breast cancer.

PubMed

Gilbert, Fiona J; van den Bosch, Harrie C M; Petrillo, Antonella; Siegmann, Katja; Heverhagen, Johannes T; Panizza, Pietro; Gehl, Hans-Björn; Pediconi, Federica; Diekmann, Felix; Peng, Wei-Jun; Ma, Lin; Sardanelli, Francesco; Belli, Paolo; Corcione, Stefano; Zechmann, Christian M; Faivre-Pierret, Matthieu; Martincich, Laura

2014-05-01

To compare gadobenate dimeglumine-enhanced magnetic resonance imaging (MRI) with gadopentetate dimeglumine-enhanced MRI, mammography, and ultrasound for breast cancer detection across different malignant lesion types and across different densities of breast tissue. In all, 153 women with Breast Imaging Reporting and Data System (BI-RADS) 3–5 findings on mammography and/or ultrasound underwent identical breast MRI exams at 1.5T with gadobenate dimeglumine and gadopentetate dimeglumine. Images were evaluated by three independent blinded radiologists. Mammography, ultrasound, and combined mammography and/or ultrasound findings were available for 108, 109, and 131 women. Imaging findings were matched with histology data by a fourth, independent, blinded radiologist. Malignant lesion detection rates and diagnostic performance were compared. In all, 120, 120, and 140 confirmed malignant lesions were present in patients undergoing MRI+mammography, MRI+ultrasound, and MRI+mammography and/or ultrasound, respectively. Significantly greater cancer detection rates were noted by all three readers for comparisons of gadobenate dimeglumine-enhanced MRI with mammography (Δ15.8–17.5%; P < 0.0001), ultrasound (Δ18.3–20.0%; P < 0.0001), and mammography and/or ultrasound (Δ8.6–10.7%; P ≤ 0.0105) but not for comparisons of gadopentetate dimeglumine-enhanced MRI with conventional techniques (P > 0.05). The false-positive detection rates were lower on gadobenate dimeglumine-enhanced MRI than on conventional imaging (4.0–5.5% vs. 11.1% at mammography; 6.3–8.4% vs. 15.5% at ultrasound). Significantly improved cancer detection on MRI was noted in heterogeneously dense breast (91.2–97.3% on gadobenate dimeglumine-enhanced MRI vs. 77.2–84.9% on gadopentetate dimeglumine-enhanced MRI vs. 71.9-84.9% with conventional techniques) and for invasive cancers (93.2–96.2% for invasive ductal carcinoma [IDC] on gadobenate dimeglumine-enhanced MRI vs. 79.7–88.5% on gadopentetate dimeglumine-enhanced MRI vs. 77.0–84.4% with conventional techniques). Overall diagnostic performance for the detection of cancer was superior on gadobenate dimeglumine-enhanced MRI than on conventional imaging or gadopentetate dimeglumine-enhanced MRI. Gadobenate dimeglumine-enhanced MRI significantly improves cancer detection compared to gadopentetate dimeglumine-enhanced MRI, mammography, and ultrasound in a selected group of patients undergoing breast MRI for preoperative staging or because of inconclusive findings at conventional imaging.

Staging of neuroendocrine tumours: comparison of [68Ga]DOTATOC multiphase PET/CT and whole-body MRI

PubMed Central

Schwenzer, N. F.; Sperling, O.; Aschoff, P.; Lichy, M. P.; Müller, M.; Brendle, C.; Werner, M. K.; Claussen, C. D.; Pfannenberg, C.

2013-01-01

Abstract Purpose: In patients with a neuroendocrine tumour (NET), the extent of disease strongly influences the outcome and multidisciplinary therapeutic management. Thus, systematic analysis of the diagnostic performance of the existing staging modalities is necessary. The aim of this study was to compare the diagnostic performance of 2 whole-body imaging modalities, [68Ga]DOTATOC positron emission tomography (PET)/computed tomography (CT) and magnetic resonance imaging (MRI) in patients with NET with regard to possible impact on treatment decisions. Materials and methods: [68Ga]DOTATOC-PET/CT and whole-body magnetic resonance imaging (wbMRI) were performed on 51 patients (25 females, 26 males, mean age 57 years) with histologically proven NET and suspicion of metastatic spread within a mean interval of 2.4 days (range 0–28 days). PET/CT was performed after intravenous administration of 150 MBq [68Ga]DOTATOC. The CT protocol comprised multiphase contrast-enhanced imaging. The MRI protocol consisted of standard sequences before and after intravenous contrast administration at 1.5 T. Each modality (PET, CT, PET/CT, wbMRI) was evaluated independently by 2 experienced readers. Consensus decision based on correlation of all imaging data, histologic and surgical findings and clinical follow-up was established as the standard of reference. Lesion-based and patient-based analysis was performed. Detection rates and accuracy were compared using the McNemar test. P values <0.05 were considered significant. The impact of whole-body imaging on the treatment decision was evaluated by the interdisciplinary tumour board of our institution. Results: 593 metastatic lesions were detected in 41 of 51 (80%) patients with NET (lung 54, liver 266, bone 131, lymph node 99, other 43). One hundred and twenty PET-negative lesions were detected by CT or MRI. Of all 593 lesions detected, PET identified 381 (64%) true-positive lesions, CT 482 (81%), PET/CT 545 (92%) and wbMRI 540 (91%). Comparison of lesion-based detection rates between PET/CT and wbMRI revealed significantly higher sensitivity of PET/CT for metastatic lymph nodes (100% vs 73%; P < 0.0001) and pulmonary lesions (100% vs 87%; P = 0.0233), whereas wbMRI had significantly higher detection rates for liver (99% vs 92%; P < 0.0001) and bone lesions (96% vs 82%; P < 0.0001). Of all 593 lesions, 22 were found only in PET, 11 only in CT and 47 only in wbMRI. The patient-based overall assessment of the metastatic status of the patient showed comparable sensitivity of PET/CT and MRI with slightly higher accuracy of PET/CT. Patient-based analysis of metastatic organ involvement revealed significantly higher accuracy of PET/CT for bone and lymph node metastases (100% vs 88%; P = 0.0412 and 98% vs 78%; P = 0.0044) and for the overall comparison (99% vs 89%; P < 0.0001). The imaging results influenced the treatment decision in 30 patients (59%) with comparable information from PET/CT and wbMRI in 30 patients, additional relevant information from PET/CT in 16 patients and from wbMRI in 7 patients. Conclusion: PET/CT and wbMRI showed comparable overall lesion-based detection rates for metastatic involvement in NET but significantly differed in organ-based detection rates with superiority of PET/CT for lymph node and pulmonary lesions and of wbMRI for liver and bone metastases. Patient-based analysis revealed superiority of PET/CT for NET staging. Individual treatment strategies benefit from complementary information from PET/CT and MRI. PMID:23466785

Environmental Influences on Diel Calling Behavior in Baleen Whales

DTIC Science & Technology

2013-09-30

to allow known calls (e.g., right whale upcall and gunshot, fin whale 20- Hz pulses, humpback whale downsweeps, sei whale low-frequency downsweeps...fin, humpback , sei, and North Atlantic right whales . Real-time detections were evaluated after recovery of the gliders by (1) comparing the acoustic...from both an aircraft and ship. The overall false detection rate for individual calls was 14%, and for right, humpback , and fin whales , false

Impact of fair bowel preparation quality on adenoma and serrated polyp detection: data from the New Hampshire colonoscopy registry by using a standardized preparation-quality rating.

PubMed

Anderson, Joseph C; Butterly, Lynn F; Robinson, Christina M; Goodrich, Martha; Weiss, Julia E

2014-09-01

The effect of colon preparation quality on adenoma detection rates (ADRs) is unclear, partly because of lack of uniform colon preparation ratings in prior studies. The New Hampshire Colonoscopy Registry collects detailed data from colonoscopies statewide, by using a uniform preparation quality scale after the endoscopist has cleaned the mucosa. To compare the overall and proximal ADR and serrated polyp detection rates (SDR) in colonoscopies with differing levels of colon preparation quality. Cross-sectional. New Hampshire statewide registry. Patients undergoing colonoscopy. We examined colon preparation quality for 13,022 colonoscopies, graded by using specific descriptions provided to endoscopists. ADR and SDR are the number of colonoscopies with at least 1 adenoma or serrated polyp (excluding those in the rectum and/or sigmoid colon) detected divided by the total number of colonoscopies, for the preparation categories: optimal (excellent and/or good), fair, and poor. Overall/proximal ADR/SDR. The overall detection rates in examinations with fair colon preparation quality (SDR 8.9%; 95% confidence interval [CI], 7.4-10.7, ADR 27.1%; 95% CI, 24.6-30.0) were similar to rates observed in colonoscopies with optimal preparation quality (SDR 8.8%; 95% CI, 8.3-9.4, ADR 26.3%; 95% CI, 25.6-27.2). This finding also was observed for rates in the proximal colon. A logistic regression model (including withdrawal time) found that proximal ADR was statistically lower in the poor preparation category (odds ratio 0.45; 95% CI, 0.24-0.84; P < .01) than in adequately prepared colons. Homogeneous population. In our sample, there was no significant difference in overall or proximal ADR or SDR between colonoscopies with fair versus optimal colon preparation quality. Poor colon preparation quality may reduce the proximal ADR. Published by Mosby, Inc.

Comparison of imaging methods for diagnosing enlarged parathyroid glands in chronic renal failure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Takagi, H.; Tominaga, Y.; Uchida, K.

1985-07-01

Three noninvasive imaging methods, CT, scintigraphy with /sup 201/TlCl and /sup 99m/TcO4-, and ultrasonography, were performed on 36 patients with chronic renal failure and secondary hyperparathyroidism. The patients subsequently underwent total parathyroidectomy and parathyroid autograft. The detection rates of the three methods for the 143 excised parathyroid glands were compared according to gland weight and location. Computed tomography detected 53.8% of all glands and 77.6% of 76 glands weighing more than 500 mg. Scintigraphy detected 51.0% of all glands and 77.6% of glands heavier than 500 mg. Ultrasonography detected 42.7% of all glands and 65.8% of glands heavier than 500more » mg. The detection rate of upper glands was best with CT (53.5 and 87.9%): that of lower glands was best with scintigraphy (62.0 and 78.6%). Although the combination of the three methods diagnosed 66.4% of all glands and 89.5% of glands heavier than 500 mg, CT and scintigraphy, the best two combinations, visualized 64.3 and 88.2%.« less

Enhanced urinalysis in the detection of asymptomatic bacteriuria in pregnancy.

PubMed

Aigere, E O S; Okusanya, B O; Eigbefoh, J O; Okome, G B O

2013-01-01

Detection and treatment of asymptomatic bacteriuria (ASB) in pregnancy is important to avert the attendant maternal and fetal morbidity. Other than urine culture, no other screening test is unequivocal. The use of enhanced urinalysis test to detect ASB in pregnancy was investigated. This was a prospective observational study which compared enhanced urinalysis with dipstick tests and urine culture. Clean catch midstream urine specimen was collected from 150 consecutive asymptomatic pregnant women. Tests of validity were used for comparison. Enhanced urinalysis detected bacteriuria as much as urine culture (4% vs. 4.7%). Itwas 57.1% sensitive and 98.6% specific. It had a false negative rate of 42.9% and was 96.7% accurate when compared to urine culture. Enhanced urinalysis took 1-2 hours to be done and required skills to use the microscope and was more expensive than dipstick urinalysis. The accuracy of enhanced urinalysis and its ability to detect ASB as much as urine culture connotes that it can be used to detect asymptomatic bacteriuria in pregnancy albeit only in secondary and tertiary health centres because of the cost and technicality involved.

Fermi Detection of a Luminous gamma-ray Pulsar in a Globular Cluster

NASA Technical Reports Server (NTRS)

Freire, P. C. C.; Abdo, A. A.; Ajello, M.; Allafort, A.; Ballet, J.; Barbiellini, G.; Bastieri, D.; Bechtol, K.; Bellazzini, R.; Blandford, R. D.;

National Lung Screening Trial: Questions and Answers

Cancer.gov

Learn the results of the National Lung Screening Trial (NLST), which compared two ways of detecting lung cancer: low-dose helical (spiral) computed tomography and standard chest X-ray, for their effects on lung cancer death rates in a high-risk population.

Prevalence of extravertebral cement leakage after vertebroplasty: procedural documentation versus CT detection.

PubMed

Martin, Douglas J; Rad, Arash Ehteshami; Kallmes, David F

2012-06-01

Reported incidence of extravertebral cement leakage after vertebroplasty varies widely across studies. To retrospectively compare the relative detection rates of extravertebral leakage noted under intra-procedural fluoroscopic surveillance, postprocedure plain radiographs, and postprocedure computed tomography (CT) in a cohort of patients undergoing vertebroplasty. With IRB approval, we retrospectively identified 181 patients with 277 levels treated with percutaneous vertebroplasty among a total of 1255 patients undergoing vertebroplasty between 1999 and 2010 who had subsequently undergone a CT examination that included the treated level(s). Categories of leakage were paravertebral, end plate, epidural, and prevertebral venous leakage. CT-detected leak rates were then compared to those noted on the vertebroplasty procedure reports and the archived fluoroscopic images for this same cohort using Pearson's χ(2) test. One hundred and forty-nine (82%, 95% CI 76-87%) of 181 patients demonstrated evidence of some type of leakage on CT at one or more treated levels. Sixty-two (34%, 95% CI 28-42%) and seventy-seven (50%, 95% CI 43-57%) of 149 CT-detected leaks were reported in the procedural dictation or detected on plain radiography (P = 0.01 and 0.006, respectively). The most common type of leakage noted on CT was end plate (n = 81, 45%, 95% CI 38-52%), followed by paravertebral (n = 64, 35%, 95% CI 29-43%), epidural (n = 36, 20%, 95% CI 15-26%), and prevertebral venous (n = 32, 18%, 95% CI 13-24%). Cement leakage after vertebroplasty is common and is often not reported by operators in procedural dictations. CT detects substantially more leaks than plain radiography.

Assessment of image quality and low-contrast detectability in abdominal CT of obese patients: comparison of a novel integrated circuit with a conventional discrete circuit detector at different tube voltages.

PubMed

Euler, A; Heye, T; Kekelidze, M; Bongartz, G; Szucs-Farkas, Z; Sommer, C; Schmidt, B; Schindera, Sebastian T

2015-03-01

To compare image quality and low-contrast detectability of an integrated circuit (IC) detector in abdominal CT of obese patients with conventional detector technology at low tube voltages. A liver phantom with 45 lesions was placed in a water container to mimic an obese patient and examined on two different CT systems at 80, 100 and 120 kVp. The systems were equipped with either the IC or conventional detector. Image noise was measured, and the contrast-to-noise-ratio (CNR) was calculated. Low-contrast detectability was assessed independently by three radiologists. Radiation dose was estimated by the volume CT dose index (CTDIvol). The image noise was significantly lower, and the CNR was significantly higher with the IC detector at 80, 100 and 120 kVp, respectively (P = 0.023). The IC detector resulted in an increased lesion detection rate at 80 kVp (38.1 % vs. 17.2 %) and 100 kVp (57.0 % vs. 41.0 %). There was no difference in the detection rate between the IC detector at 100 kVp and the conventional detector at 120 kVp (57.0 % vs. 62.2 %). The CTDIvol at 80, 100 and 120 kVp measured 4.5-5.2, 7.3-7.9 and 9.8-10.2 mGy, respectively. The IC detector at 100 kVp resulted in similar low-contrast detectability compared to the conventional detector with a 120-kVp protocol at a radiation dose reduction of 37 %.

Merging Black Hole Binaries in Galactic Nuclei: Implications for Advanced-LIGO Detections

NASA Astrophysics Data System (ADS)

Antonini, Fabio; Rasio, Frederic A.

2016-11-01

Motivated by the recent detection of gravitational waves from the black hole binary merger GW150914, we study the dynamical evolution of (stellar-mass) black holes in galactic nuclei, where massive star clusters reside. With masses of ˜ {10}7 {M}⊙ and sizes of only a few parsecs, nuclear star clusters (NSCs) are the densest stellar systems observed in the local universe and represent a robust environment where black hole binaries can dynamically form, harden, and merge. We show that due to their large escape speeds, NSCs can retain a large fraction of their merger remnants. Successive mergers can then lead to significant growth and produce black hole mergers of several tens of solar masses similar to GW150914 and up to a few hundreds of solar masses, without the need to invoke extremely low metallicity environments. We use a semi-analytical approach to describe the dynamics of black holes in massive star clusters. Our models give a black hole binary merger rate of ≈ 1.5 {{Gpc}}-3 {{yr}}-1 from NSCs, implying up to a few tens of possible detections per year with Advanced LIGO. Moreover, we find a local merger rate of ˜ 1 {{Gpc}}-3 {{yr}}-1 for high mass black hole binaries similar to GW150914; a merger rate comparable to or higher than that of similar binaries assembled dynamically in globular clusters (GCs). Finally, we show that if all black holes receive high natal kicks, ≳ 50 {km} {{{s}}}-1, then NSCs will dominate the local merger rate of binary black holes compared to either GCs or isolated binary evolution.

Theileria infection in domestic ruminants in northern Ethiopia.

PubMed

Gebrekidan, Hagos; Hailu, Asrat; Kassahun, Aysheshm; Rohoušová, Iva; Maia, Carla; Talmi-Frank, Dalit; Warburg, Alon; Baneth, Gad

2014-02-24

Piroplasmosis caused by different tick-borne hemoprotozoan parasites of the genera Theileria and Babesia is among the most economically important infections of domestic ruminants in sub-Saharan Africa. A survey for piroplasm infection was conducted in three locations in Northern Ethiopia. Of 525 domestic ruminants surveyed, 80% of the cattle, 94% of the sheep and 2% of the goats were positive for different Theileria spp. based on PCR of blood followed by DNA sequencing. Sheep had a significantly higher rate of infection compared with cattle (P<0.0003) and both sheep and cattle had higher rates of infection compared to goats (P<0.0001). Four species of Theileria were detected in cattle: T. velifera, T. mutans, T. orientalis complex and T. annulata with infection rates of 66, 8, 4, and 2%, respectively. This is the first report of T. annulata, the cause of Tropical Theileriosis in Ethiopia. Of the two Theileria spp. detected in small ruminants, T. ovis was highly prevalent (92%) in sheep and rare in goats (1.5%) whereas T. seperata was infrequent in sheep (2%) and rare in goats (0.4%). None of the animals were positive for Babesia spp.; however, Sarcocystis capracanis and S. tenella were detected in one goat and a sheep, respectively. The widespread distribution of Theileria spp. among cattle in northern Ethiopia including the virulent T. annulata and more mildly pathogenic T. mutans and T. orientalis, and the high infection rate in sheep with the usually sub-clinical T. ovis indicate extensive exposure to ticks and transmission of piroplasms with an important economic impact. Copyright © 2013 Elsevier B.V. All rights reserved.

Individual variation in habituation: behaviour over time toward different stimuli in threespine sticklebacks (Gasterosteus aculeatus)

PubMed Central

Bell, Alison M.; Peeke, Harman V.S.

2014-01-01

Habituation, or the relatively permanent waning of a response as a result of repeated stimulation, is a form of behavioural plasticity that allows animals to filter out irrelevant stimuli and to focus selectively on important stimuli. Individuals that fail to habituate might be at a disadvantage if they continue to respond to irrelevant stimuli; therefore, habituation can have adaptive significance. In this study we compared rates of behaviour over time toward three different ecologically-relevant stimuli (food, a male intruder and a gravid female) in threespine sticklebacks (Gasterosteus aculeatus). We detected evidence for habituation to the stimuli, and males in this study were especially aggressive toward both male and female conspecifics. Although there were some clear temporal patterns that could be detected by looking at average behaviour, not all individuals behaved in the same ‘average’ way. We detected substantial inter-individual variation in behaviour toward all three stimuli, inter-individual variation in rates of habituation to both male and female conspecifics, but no evidence for correlations between behaviours across stimuli (behavioural syndromes). These results suggest that individual animals vary in rates of habituation, and prompt hypotheses about the causes and consequences of variation in rates of habituation. PMID:25678715

PCR Testing of IVC Filter Tops as a Method for Detecting Murine Pinworms and Fur Mites.

PubMed

Gerwin, Philip M; Ricart Arbona, Rodolfo J; Riedel, Elyn R; Henderson, Kenneth S; Lipman, Neil S

2017-11-01

We evaluated PCR testing of filter tops from cages maintained on an IVC system through which exhaust air is filtered at the cage level as a method for detecting parasite-infected and -infested cages. Cages containing 4 naïve Swiss Webster mice received 360 mL of uncontaminated aspen chip or α-cellulose bedding (n = 18 cages each) and 60 mL of the same type of bedding weekly from each of the following 4 groups of cages housing mice infected or infested with Syphacia obvelata (SO), Aspiculuris tetraptera (AT), Myocoptes musculinus (MC), or Myobia musculi (MB) and Radfordia affinis (RA; 240 mL bedding total). Detection rates were compared at 30, 60, and 90 d after initiating bedding exposure, by using PCR analysis of filter tops (media extract and swabs) and testing of mouse samples (fur swab [direct] PCR testing, fecal flotation, anal tape test, direct examination of intestinal contents, and skin scrape). PCR testing of filter media extract detected 100% of all parasites at 30 d (both bedding types) except for AT (α-cellulose bedding, 67% detection rate); identified more cages with fur mites (MB and MC) than direct PCR when cellulose bedding was used; and was better at detecting parasites than all nonmolecular methods evaluated. PCR analysis of filter media extract was superior to swab and direct PCR for all parasites cumulatively for each bedding type. Direct PCR more effectively detected MC and all parasites combined for aspen chip compared with cellulose bedding. PCR analysis of filter media extract for IVC systems in which exhaust air is filtered at the cage level was shown to be a highly effective environmental testing method.

Investigation of Legionella Contamination in Bath Water Samples by Culture, Amoebic Co-Culture, and Real-Time Quantitative PCR Methods.

PubMed

Edagawa, Akiko; Kimura, Akio; Kawabuchi-Kurata, Takako; Adachi, Shinichi; Furuhata, Katsunori; Miyamoto, Hiroshi

2015-10-19

We investigated Legionella contamination in bath water samples, collected from 68 bathing facilities in Japan, by culture, culture with amoebic co-culture, real-time quantitative PCR (qPCR), and real-time qPCR with amoebic co-culture. Using the conventional culture method, Legionella pneumophila was detected in 11 samples (11/68, 16.2%). Contrary to our expectation, the culture method with the amoebic co-culture technique did not increase the detection rate of Legionella (4/68, 5.9%). In contrast, a combination of the amoebic co-culture technique followed by qPCR successfully increased the detection rate (57/68, 83.8%) compared with real-time qPCR alone (46/68, 67.6%). Using real-time qPCR after culture with amoebic co-culture, more than 10-fold higher bacterial numbers were observed in 30 samples (30/68, 44.1%) compared with the same samples without co-culture. On the other hand, higher bacterial numbers were not observed after propagation by amoebae in 32 samples (32/68, 47.1%). Legionella was not detected in the remaining six samples (6/68, 8.8%), irrespective of the method. These results suggest that application of the amoebic co-culture technique prior to real-time qPCR may be useful for the sensitive detection of Legionella from bath water samples. Furthermore, a combination of amoebic co-culture and real-time qPCR might be useful to detect viable and virulent Legionella because their ability to invade and multiply within free-living amoebae is considered to correlate with their pathogenicity for humans. This is the first report evaluating the efficacy of the amoebic co-culture technique for detecting Legionella in bath water samples.

PCR Testing of IVC Filter Tops as a Method for Detecting Murine Pinworms and Fur Mites

PubMed Central

Gerwin, Philip M; Arbona, Rodolfo J Ricart; Riedel, Elyn R; Henderson, Kenneth S; Lipman, Neil S

2017-01-01

We evaluated PCR testing of filter tops from cages maintained on an IVC system through which exhaust air is filtered at the cage level as a method for detecting parasite- infected and -infested cages. Cages containing 4 naïve Swiss Webster mice received 360 mL of uncontaminated aspen chip or α-cellulose bedding (n = 18 cages each) and 60 mL of the same type of bedding weekly from each of the following 4 groups of cages housing mice infected or infested with Syphacia obvelata (SO), Aspiculuris tetraptera (AT), Myocoptes musculinus (MC), or Myobia musculi (MB) and Radfordia affinis (RA; 240 mL bedding total). Detection rates were compared at 30, 60, and 90 d after initiating bedding exposure, by using PCR analysis of filter tops (media extract and swabs) and testing of mouse samples (fur swab [direct] PCR testing, fecal flotation, anal tape test, direct examination of intestinal contents, and skin scrape). PCR testing of filter media extract detected 100% of all parasites at 30 d (both bedding types) except for AT (α-cellulose bedding, 67% detection rate); identified more cages with fur mites (MB and MC) than direct PCR when cellulose bedding was used; and was better at detecting parasites than all nonmolecular methods evaluated. PCR analysis of filter media extract was superior to swab and direct PCR for all parasites cumulatively for each bedding type. Direct PCR more effectively detected MC and all parasites combined for aspen chip compared with cellulose bedding. PCR analysis of filter media extract for IVC systems in which exhaust air is filtered at the cage level was shown to be a highly effective environmental testing method. PMID:29256370

Investigation of Legionella Contamination in Bath Water Samples by Culture, Amoebic Co-Culture, and Real-Time Quantitative PCR Methods

PubMed Central

Edagawa, Akiko; Kimura, Akio; Kawabuchi-Kurata, Takako; Adachi, Shinichi; Furuhata, Katsunori; Miyamoto, Hiroshi

2015-01-01

We investigated Legionella contamination in bath water samples, collected from 68 bathing facilities in Japan, by culture, culture with amoebic co-culture, real-time quantitative PCR (qPCR), and real-time qPCR with amoebic co-culture. Using the conventional culture method, Legionella pneumophila was detected in 11 samples (11/68, 16.2%). Contrary to our expectation, the culture method with the amoebic co-culture technique did not increase the detection rate of Legionella (4/68, 5.9%). In contrast, a combination of the amoebic co-culture technique followed by qPCR successfully increased the detection rate (57/68, 83.8%) compared with real-time qPCR alone (46/68, 67.6%). Using real-time qPCR after culture with amoebic co-culture, more than 10-fold higher bacterial numbers were observed in 30 samples (30/68, 44.1%) compared with the same samples without co-culture. On the other hand, higher bacterial numbers were not observed after propagation by amoebae in 32 samples (32/68, 47.1%). Legionella was not detected in the remaining six samples (6/68, 8.8%), irrespective of the method. These results suggest that application of the amoebic co-culture technique prior to real-time qPCR may be useful for the sensitive detection of Legionella from bath water samples. Furthermore, a combination of amoebic co-culture and real-time qPCR might be useful to detect viable and virulent Legionella because their ability to invade and multiply within free-living amoebae is considered to correlate with their pathogenicity for humans. This is the first report evaluating the efficacy of the amoebic co-culture technique for detecting Legionella in bath water samples. PMID:26492259

Airport arrivals screening during pandemic (H1N1) 2009 influenza in New South Wales, Australia.

PubMed

Gunaratnam, Praveena J; Tobin, Sean; Seale, Holly; Marich, Andrew; McAnulty, Jeremy

2014-03-17

To examine the effectiveness of airport screening in New South Wales during pandemic (H1N1) 2009 influenza. Analysis of data collected at clinics held at Sydney Airport, and of all notified cases of influenza A(H1N1)pdm09, between 28 April 2009 and 18 June 2009. Case detection rate per 100,000 passengers screened, sensitivity, positive predictive value and specificity of airport screening. The proportion of all cases in the period detected at airport clinics was compared with the proportion detected in emergency departments and general practice. Of an estimated 625,147 passenger arrivals at Sydney Airport during the period, 5845 (0.93%) were identified as being symptomatic or febrile, and three of 5845 were subsequently confirmed to have influenza A(H1N1)pdm09, resulting in a detection rate of 0.05 per 10,000 screened (95% CI, 0.02-1.14 per 10,000). Forty-five patients with overseas-acquired influenza A(H1N1)pdm09 in NSW would have probably passed through the airport during this time, giving airport screening a sensitivity of 6.67% (95% CI, 1.40%-18.27%). Positive predictive value was 0.05% (95% CI, 0.02%-0.15%) and specificity 99.10% (95% CI, 99.00%-100.00%). Of the 557 confirmed cases across NSW during the period, 290 (52.1%) were detected at emergency departments and 135 (24.2%) at general practices, compared with three (0.5%) detected at the airport. Airport screening was ineffective in detecting cases of influenza A(H1N1)pdm09 in NSW. Its future use should be carefully considered against potentially more effective interventions, such as contact tracing in the community.

Radiation detectors and sources enhanced with micro/nanotechnology

NASA Astrophysics Data System (ADS)

Whitney, Chad Michael

The ongoing threat of nuclear terrorism presents major challenges to maintaining national security. Currently, only a small percentage of the cargo containers that enter America are searched for fissionable bomb making materials. This work reports on a multi-channel radiation detection platform enabled with nanoparticles that is capable of detecting and discriminating all types of radiation emitted from fissionable bomb making materials. Typical Geiger counters are limited to detecting only beta and gamma radiation. The micro-Geiger counter reported here detects all species of radiation including beta particles, gamma/X-rays, alpha particles, and neutrons. The multi-species detecting micro-Geiger counter contains a hermetically sealed and electrically biased fill gas. Impinging radiation interacts with tailored nanoparticles to release secondary charged particles that ionize the fill gas. The ionized particles collect on respectively biased electrodes resulting in a characteristic electrical pulse. Pulse height spectroscopy and radiation energy binning techniques can then be used to analyze the pulses to determine the specific radiation isotope. The ideal voltage range of operation for energy discrimination was found to be in the proportional region at 1000VDC. In this region, specific pulse heights for different radiation species resulted. The amplification region strength which determines the device sensitivity to radiation energy can be tuned with the electrode separation distance. Considerable improvements in count rates were achieved by using the charge conversion nanoparticles with the highest cross sections for particular radiation species. The addition of tungsten nanoparticles to the microGeiger counter enabled the device to be four times more efficient at detecting low level beta particles with a dose rate of 3.2uR/hr (micro-Roentgen per hour) and just under three times more efficient than an off the shelf Geiger counter. The addition of lead nanoparticles enabled the gamma/X-ray microGeiger counter channel to be 28 times more efficient at detecting low level gamma rays with a dose rate of 10uR/hr when compared to a device without nanoparticles. The addition of 10B nanoparticles enabled the neutron microGeiger counter channel to be 17 times more efficient at detecting neutrons. The device achieved a neutron count rate of 9,866 counts per minute when compared to a BF3 tube which resulted in a count rate of 9,000 counts per minute. By using a novel micro-injection ceramic molding and low temperature (950°C) silver paste metallizing process, the batch fabrication of essentially disposable micro-devices can be achieved. This novel fabrication technique was then applied to a MEMS neutron gun and water spectroscopy device that also utilizes the high voltage/temperature insulating packaging.

INTESTINAL PARASITES IN DIABETIC PATIENTS IN SOHAG UNIVERSITY HOSPITALS, EGYPT.

PubMed

Elnadi, Nada A; Hassanien, Hassan A; Ahmad, Amal M; Abd Ellah, Asmaa K

2015-08-01

Intestinal parasites usually create benign diseases, though they may induce complications with high morbidity and mortality to the immunocompromised, including diabetic patients. The study detected the prevalence of intestinal parasitic infections in diabetic patients, comparing to non-diabetic controls and other parameters. A total of 100 fecal samples were collected from diabetic patients at the outpatient clinic of Sohag University Hospitals and another 100 from cross matched controls. The samples were examined macroscopically and microscopically by direct smear and different concentration methods then stained by Modified Ziehl-Neelsen Acid fast stain. Glycated hemoglobin (Hb Alc) was measured to detect DM controlled patients. The data were organized, tabulated, and statistically analyzed. Intestinal parasites were found in 25 (25%) cases out of 100 patients in diabetic group and 7(7%) cases out of 100 controls with high significance (P<0.001)). In the diabetic group, Giardia lamblia was detected in 22 cases (22%) and 5 (5%) among controls, Entamoeba histolytica in 7 cases (7%) and 3 (3%) among controls, Hymenolypis nana in 5 cases (5%) and 3 (3%) among controls, Entamoeba coli in 8 patients (8%), Entamoeba hartmanni in 3 cases (3%), Dientamoeba fragilis in a case (1%), Cryptosporidium parvum in 5 cases (5%) and microsporidia in 3 cases (3%). But, E. coli, E. hartmanni, D. fragilis and C. parvum nor microsporidia were detected in controls. The rate of G. lamblia in DM patients compared to controls was high significant (P<0.001). Hymenolepis nana was 5% (5 cases) in diabetic patients compared to 3% (3 cases) in controls. Residence and sex differences were not significant, while age, >10 years showed the highest prevalence (P< 0.003), type I infection rate was significantly higher than type II (P<0.001). DM control was also significantly affected the infection rates (P<0.007 in type I and P< 0.01 in type II).

A comparison between atmospheric/humidity and vacuum cyanoacrylate fuming of latent fingermarks.

PubMed

Farrugia, Kevin J; Fraser, Joanna; Friel, Lauren; Adams, Duncan; Attard-Montalto, Nicola; Deacon, Paul

2015-12-01

A number of pseudo-operational trials were set up to compare the atmospheric/humidity and vacuum cyanoacrylate fuming processes on plastic carrier bags. The fuming processes were compared using two-step cyanoacrylate fuming with basic yellow 40 (BY40) staining and a one-step fluorescent cyanoacrylate fuming, Lumicyano 4%. Preliminary work using planted fingermarks and split depletions were performed to identify the optimum vacuum fuming conditions. The first pseudo-operational trial compared the different fuming conditions (atmospheric/humidity vs. vacuum) for the two-step process where an additional 50% more marks were detected with the atmospheric/humidity process. None of the marks by the vacuum process could be observed visually; however, a significant number of marks were detected by fluorescence after BY40 staining. The second trial repeated the same work in trial 1 using the one-step cyanoacrylate process, Lumicyano at a concentration of 4%. Trial 2 provided comparable results to trial 1 and all the items were then re-treated with Lumicyano 4% at atmospheric/humidity conditions before dyeing with BY40 to provide the sequences of process A (Lumicyano 4% atmospheric-Lumicyano 4% atmospheric-BY40) and process B (Lumicyano 4% vacuum-Lumicyano 4% atmospheric-BY40). The number of marks (visual and fluorescent) was counted after each treatment with a substantial increase in the number of detected marks in the second and third treatments of the process. The increased detection rate after the double Lumicyano process was unexpected and may have important implications. Trial 3 was performed to investigate whether the amount of cyanoacrylate and/or fuming time had an impact on the results observed in trial 2 whereas trial 4 assessed if the double process using conventional cyanoacrylate, rather than Lumicyano 4%, provided an increased detection rate. Trials 3 and 4 confirmed that doubling the amount of Lumicyano 4% cyanoacrylate and fuming time produced a lower detection rate than the double process with Lumicyano 4%. Furthermore, the double process with conventional cyanoacrylate did not provide any benefit. Scanning electron microscopy was also performed to investigate the morphology of the cyanoacrylate polymer under different conditions. The atmospheric/humidity process appears to be superior to the vacuum process for both the two-step and one-step cyanoacrylate fuming, although the two-step process performed better in comparison to the one-step process under vacuum conditions. Nonetheless, the use of vacuum cyanoacrylate fuming may have certain operational advantages and its use does not adversely affect subsequent cyanoacrylate fuming with atmospheric/humidity conditions. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Association of Mycoplasma pneumoniae infection with increased risk of asthma in children.

PubMed

Yin, Sha-Sha; Ma, Feng-Lian; Gao, Xing

2017-05-01

The present study was conducted to investigate the relationship between Mycoplasma pneumoniae (MP) infection and the risk of asthma among children by detecting the rate of MP immunoglobulin M (MP-IgM) and the eosinophil (EOS) count. A total of 139 asthmatic children were enrolled as the case group and assigned into three groups: Group A (aged <3 years, n=42), group B (aged 3-8 years, n=45) and group C (aged >8 years, n=52). Additionally, 115 healthy children were enrolled in the control group. Enzyme-linked immunosorbent assay was used to measure the MP-IgM-positive rate. EOS count was detected in the experimental and control groups by using a hemocytometer analyzer. A meta-analysis was performed by using the Comprehensive Meta-Analysis version 2.0 software. The positive rates of the MP-IgM and EOS count in the experimental group were significantly higher than those in control group (both P<0.001). Furthermore, the asthmatic children in group C had a higher MP-IgM-positive rate and EOS count as compared to those in groups A and B, respectively (all P<0.05). Results from groups A and B were not statistically significant (all P>0.05). The meta-analysis further confirmed that asthmatic children had a higher MP-IgM-positive rate as compared to the healthy controls (P<0.001). Age-stratified analysis revealed that the MP-IgM-positive rate in asthmatic children aged ≥8 and <8 years was significantly higher than that in the healthy controls (P=0.003 and P<0.001). Asthmatic children had a higher MP-IgM-positive rate and EOS count as compared with controls, suggesting that the MP infection may be closely associated with the risk of asthma. Additionally, the positive rate of MP-IgM may indicate an important biological marker in predicting the development of asthma.

Impact of changing from staining to culture techniques on detection rates of Campylobacter spp. in routine stool samples in Chile.

PubMed

Porte, Lorena; Varela, Carmen; Haecker, Thomas; Morales, Sara; Weitzel, Thomas

2016-05-13

Campylobacter is a leading cause of bacterial gastroenteritis, but sensitive diagnostic methods such as culture are expensive and often not available in resource limited settings. Therefore, direct staining techniques have been developed as a practical and economical alternative. We analyzed the impact of replacing Campylobacter staining with culture for routine stool examinations in a private hospital in Chile. From January to April 2014, a total of 750 consecutive stool samples were examined in parallel by Hucker stain and Campylobacter culture. Isolation rates of Campylobacter were determined and the performance of staining was evaluated against culture as the gold standard. Besides, isolation rates of Campylobacter and other enteric pathogens were compared to those of past years. Campylobacter was isolated by culture in 46 of 750 (6.1 %) stool samples. Direct staining only identified three samples as Campylobacter positive and reached sensitivity and specificity values of 6.5 and 100 %, respectively. In comparison to staining-based detection rates of previous years, we observed a significant increase of Campylobacter cases in our patients. Direct staining technique for Campylobacter had a very low sensitivity compared to culture. Staining methods might lead to a high rate of false negative results and an underestimation of the importance of campylobacteriosis. With the inclusion of Campylobacter culture, this pathogen became a leading cause of intestinal infection in our patient population.

Disease management: atrial fibrillation and home monitoring.

PubMed

Ricci, Renato Pietro

2013-06-01

Device-detected atrial fibrillation (AF) episodes predict poor clinical outcome regardless of symptoms. Potential benefits of remote monitoring are early arrhythmia detection and patient continuous monitoring. Several studies of device remote monitoring consistently demonstrated that AF represents the most common clinical alert and that detailed information on arrhythmia onset, duration, and burden as well as on the ventricular rate may be early available for clinical evaluation. Reaction time to AF alerts was very short in all series involving either pacemakers or defibrillators and action ability of AF alerts was very high. In the Home Guide Registry, in which 1650 patients were enrolled, AF was detected in 16.3% of patients and represented 36% of all cardiovascular events during the follow-up. Timely anticoagulation introduction in asymptomatic patients may impact on the stroke rate. According to the results of repeated Monte Carlo simulations based on a real population of 166 patients, daily monitoring may reduce the 2-year stroke risk by 9-18% with an absolute reduction of 0.2-0.6%, compared with conventional inter-visit intervals of 6-12 months. In the COMPAS trial, the incidence of hospitalizations for atrial arrhythmias and related stroke was significantly higher in the control group than in the remote monitoring group. Major questions will be addressed by the ongoing IMPACT trial in which a remote monitoring guided anticoagulation strategy based on AF detection will be compared with a physician-directed standard strategy. In patients with heart failure, AF early detection combined with other indexes may help prevent hospitalizations.

Lymphovascular invasion in more than one-quarter of small rectal neuroendocrine tumors

PubMed Central

Kwon, Mi Jung; Kang, Ho Suk; Soh, Jae Seung; Lim, Hyun; Kim, Jong Hyeok; Park, Choong Kee; Park, Hye-Rim; Nam, Eun Sook

2016-01-01

AIM To identify the frequency, clinicopathological risk factors, and prognostic significance of lymphovascular invasion (LVI) in endoscopically resected small rectal neuroendocrine tumors (NETs). METHODS Between June 2005 and December 2015, 104 cases of endoscopically resected small (≤ 1 cm) rectal NET specimens at Hallym University Sacred Heart Hospital in Korea were retrospectively evaluated. We compared the detected rate of LVI in small rectal NET specimens by two methods: hematoxylin and eosin (H&E) and ancillary immunohistochemical staining (D2-40 and Elastica van Gieson); in addition, LVI detection rate difference between endoscopic procedures were also evaluated. Patient characteristics, prognosis and endoscopic resection results were reviewed by medical charts. RESULTS We observed LVI rates of 25.0% and 27.9% through H&E and ancillary immunohistochemical staining. The concordance rate between H&E and ancillary studies was 81.7% for detection of LVI, which showed statistically strong agreement between two methods (κ = 0.531, P < 0.001). Two endoscopic methods were studied, including endoscopic submucosal resection with a ligation device and endoscopic submucosal dissection, and no statistically significant difference in the LVI detection rate was detected between the two (26.3% and 26.8%, P = 0.955). LVI was associated with large tumor size (> 5 mm, P = 0.007), tumor grade 2 (P = 0.006). Among those factors, tumor grade 2 was the only independent predictive factor for the presence of LVI (HR = 4.195, 95%CI: 1.321-12.692, P = 0.015). No recurrence was observed over 28.8 mo regardless of the presence of LVI. CONCLUSION LVI may be present in a high percentage of small rectal NETs, which may not be associated with short-term prognosis. PMID:27895428

The Detection Rate of Early UV Emission from Supernovae: A Dedicated Galex/PTF Survey and Calibrated Theoretical Estimates

NASA Astrophysics Data System (ADS)

Ganot, Noam; Gal-Yam, Avishay; Ofek, Eran. O.; Sagiv, Ilan; Waxman, Eli; Lapid, Ofer; Kulkarni, Shrinivas R.; Ben-Ami, Sagi; Kasliwal, Mansi M.; The ULTRASAT Science Team; Chelouche, Doron; Rafter, Stephen; Behar, Ehud; Laor, Ari; Poznanski, Dovi; Nakar, Ehud; Maoz, Dan; Trakhtenbrot, Benny; WTTH Consortium, The; Neill, James D.; Barlow, Thomas A.; Martin, Christofer D.; Gezari, Suvi; the GALEX Science Team; Arcavi, Iair; Bloom, Joshua S.; Nugent, Peter E.; Sullivan, Mark; Palomar Transient Factory, The

2016-03-01

The radius and surface composition of an exploding massive star, as well as the explosion energy per unit mass, can be measured using early UV observations of core-collapse supernovae (SNe). We present the first results from a simultaneous GALEX/PTF search for early ultraviolet (UV) emission from SNe. Six SNe II and one Type II superluminous SN (SLSN-II) are clearly detected in the GALEX near-UV (NUV) data. We compare our detection rate with theoretical estimates based on early, shock-cooling UV light curves calculated from models that fit existing Swift and GALEX observations well, combined with volumetric SN rates. We find that our observations are in good agreement with calculated rates assuming that red supergiants (RSGs) explode with fiducial radii of 500 R ⊙, explosion energies of 1051 erg, and ejecta masses of 10 M ⊙. Exploding blue supergiants and Wolf-Rayet stars are poorly constrained. We describe how such observations can be used to derive the progenitor radius, surface composition, and explosion energy per unit mass of such SN events, and we demonstrate why UV observations are critical for such measurements. We use the fiducial RSG parameters to estimate the detection rate of SNe during the shock-cooling phase (<1 day after explosion) for several ground-based surveys (PTF, ZTF, and LSST). We show that the proposed wide-field UV explorer ULTRASAT mission is expected to find >85 SNe per year (˜0.5 SN per deg2), independent of host galaxy extinction, down to an NUV detection limit of 21.5 mag AB. Our pilot GALEX/PTF project thus convincingly demonstrates that a dedicated, systematic SN survey at the NUV band is a compelling method to study how massive stars end their life.

[Application of automatic photography in Schistosoma japonicum miracidium hatching experiments].

PubMed

Ming-Li, Zhou; Ai-Ling, Cai; Xue-Feng, Wang

2016-05-20

To explore the value of automatic photography in the observation of results of Schistosoma japonicum miracidium hatching experiments. Some fresh S. japonicum eggs were added into cow feces, and the samples of feces were divided into a low infested experimental group and a high infested group (40 samples each group). In addition, there was a negative control group with 40 samples of cow feces without S. japonicum eggs. The conventional nylon bag S. japonicum miracidium hatching experiments were performed. The process was observed with the method of flashlight and magnifying glass combined with automatic video (automatic photography method), and, at the same time, with the naked eye observation method. The results were compared. In the low infested group, the miracidium positive detection rates were 57.5% and 85.0% by the naked eye observation method and automatic photography method, respectively ( χ 2 = 11.723, P < 0.05). In the high infested group, the positive detection rates were 97.5% and 100% by the naked eye observation method and automatic photography method, respectively ( χ 2 = 1.253, P > 0.05). In the two infested groups, the average positive detection rates were 77.5% and 92.5% by the naked eye observation method and automatic photography method, respectively ( χ 2 = 6.894, P < 0.05). The automatic photography can effectively improve the positive detection rate in the S. japonicum miracidium hatching experiments.

Lunar Impact Detections During the 2010 Geminid Meteor Shower

NASA Technical Reports Server (NTRS)

Suggs, Ron; Suggs, Rob; Moser, Danielle; Blaauw, Rhiannon

2011-01-01

Lunar video observations are routinely conducted at the NASA Marshall Space Flight Center in Huntsville Alabama for the detection of meteoroid impacts. Over 240 impacts have been detected since the start of the observing program initiated approximately 5 years ago. During this time it has been fairly rare that lunar observing conditions and the weather have been favorable during the peak of the major showers. However, observing conditions were marginally favorable during the peak of the 2010 Geminids. On Dec. 14, 2010 approximately 5.5 hours of video were recorded. Even though the lunar phase was just outside the constraints established for optimum lunar impact monitoring, the resulting video was of sufficient quality that 21 lunar impacts were detected yielding an average impact rate of approximately 4 per hour. This compares to 17 lunar impacts detected over 40 nights of observations ( approximately 100 hours of lunar video) yielding an average impact rate of 1 per 6 hours for the whole of 2010, excluding Dec. 14. The results of the 2010 Geminid lunar impact detections will be discussed along with previous results from the 2006 Geminid shower that also coincided within the lunar observing window.

Systolic peak detection in acceleration photoplethysmograms measured from emergency responders in tropical conditions.

PubMed

Elgendi, Mohamed; Norton, Ian; Brearley, Matt; Abbott, Derek; Schuurmans, Dale

2013-01-01

Photoplethysmogram (PPG) monitoring is not only essential for critically ill patients in hospitals or at home, but also for those undergoing exercise testing. However, processing PPG signals measured after exercise is challenging, especially if the environment is hot and humid. In this paper, we propose a novel algorithm that can detect systolic peaks under challenging conditions, as in the case of emergency responders in tropical conditions. Accurate systolic-peak detection is an important first step for the analysis of heart rate variability. Algorithms based on local maxima-minima, first-derivative, and slope sum are evaluated, and a new algorithm is introduced to improve the detection rate. With 40 healthy subjects, the new algorithm demonstrates the highest overall detection accuracy (99.84% sensitivity, 99.89% positive predictivity). Existing algorithms, such as Billauer's, Li's and Zong's, have comparable although lower accuracy. However, the proposed algorithm presents an advantage for real-time applications by avoiding human intervention in threshold determination. For best performance, we show that a combination of two event-related moving averages with an offset threshold has an advantage in detecting systolic peaks, even in heat-stressed PPG signals.

Detection of abnormal item based on time intervals for recommender systems.

PubMed

Gao, Min; Yuan, Quan; Ling, Bin; Xiong, Qingyu

2014-01-01

With the rapid development of e-business, personalized recommendation has become core competence for enterprises to gain profits and improve customer satisfaction. Although collaborative filtering is the most successful approach for building a recommender system, it suffers from "shilling" attacks. In recent years, the research on shilling attacks has been greatly improved. However, the approaches suffer from serious problem in attack model dependency and high computational cost. To solve the problem, an approach for the detection of abnormal item is proposed in this paper. In the paper, two common features of all attack models are analyzed at first. A revised bottom-up discretized approach is then proposed based on time intervals and the features for the detection. The distributions of ratings in different time intervals are compared to detect anomaly based on the calculation of chi square distribution (χ(2)). We evaluated our approach on four types of items which are defined according to the life cycles of these items. The experimental results show that the proposed approach achieves a high detection rate with low computational cost when the number of attack profiles is more than 15. It improves the efficiency in shilling attacks detection by narrowing down the suspicious users.

Probabilistic model for quick detection of dissimilar binary images

NASA Astrophysics Data System (ADS)

Mustafa, Adnan A. Y.

2015-09-01

We present a quick method to detect dissimilar binary images. The method is based on a "probabilistic matching model" for image matching. The matching model is used to predict the probability of occurrence of distinct-dissimilar image pairs (completely different images) when matching one image to another. Based on this model, distinct-dissimilar images can be detected by matching only a few points between two images with high confidence, namely 11 points for a 99.9% successful detection rate. For image pairs that are dissimilar but not distinct-dissimilar, more points need to be mapped. The number of points required to attain a certain successful detection rate or confidence depends on the amount of similarity between the compared images. As this similarity increases, more points are required. For example, images that differ by 1% can be detected by mapping fewer than 70 points on average. More importantly, the model is image size invariant; so, images of any sizes will produce high confidence levels with a limited number of matched points. As a result, this method does not suffer from the image size handicap that impedes current methods. We report on extensive tests conducted on real images of different sizes.

Fast detection of atrazine in corn using thermometric biosensors.

PubMed

Qie, Zhiwei; Ning, Baoan; Liu, Ming; Bai, Jialei; Peng, Yuan; Song, Nan; Lv, Zhiqiang; Wang, Ying; Sun, Siming; Su, Xuan; Zhang, Yihong; Gao, Zhixian

2013-09-07

Fast detection is important in screening large-scale samples. This study establishes a direct competitive ELISA method (dcTELISA) based on an enzyme thermistor for fast atrazine (ATZ) detection. ATZ competes with β-lactamase-labeled ATZ (ATZ-E) for the binding sites on anti-ATZ monoclonal antibody (mAb). The mAb are covalently bound to Controlled Pore Glass (CPG) in an immunoreactor to form immunocomplexes with ATZ and ATZ-E. Several parameters of biosensor performance were optimized, such as the ATZ-E concentration, concentration and nature of the substrate, flow rate, and effect of temperature on the sensor response. After optimization, the assay time for a single sample was 12 min. The work process and result were compared with those of high-performance liquid chromatography (HPLC). The detection results exhibited a recovery rate of 88% to 107% in ATZ-spiked fresh cut corn stalks and silage samples. The results obtained via dcTELISA had good correlation with that of HPLC, and the biosensor response was reproducible and stable even when used continuously for over 4 months. All these properties suggested that the fast detection method, dcTELISA, may be used to detect pesticide residue in large-scale samples.

Geologic Carbon Sequestration Leakage Detection: A Physics-Guided Machine Learning Approach

NASA Astrophysics Data System (ADS)

Lin, Y.; Harp, D. R.; Chen, B.; Pawar, R.

2017-12-01

One of the risks of large-scale geologic carbon sequestration is the potential migration of fluids out of the storage formations. Accurate and fast detection of this fluids migration is not only important but also challenging, due to the large subsurface uncertainty and complex governing physics. Traditional leakage detection and monitoring techniques rely on geophysical observations including pressure. However, the resulting accuracy of these methods is limited because of indirect information they provide requiring expert interpretation, therefore yielding in-accurate estimates of leakage rates and locations. In this work, we develop a novel machine-learning technique based on support vector regression to effectively and efficiently predict the leakage locations and leakage rates based on limited number of pressure observations. Compared to the conventional data-driven approaches, which can be usually seem as a "black box" procedure, we develop a physics-guided machine learning method to incorporate the governing physics into the learning procedure. To validate the performance of our proposed leakage detection method, we employ our method to both 2D and 3D synthetic subsurface models. Our novel CO2 leakage detection method has shown high detection accuracy in the example problems.

Unified framework for triaxial accelerometer-based fall event detection and classification using cumulants and hierarchical decision tree classifier.

PubMed

Kambhampati, Satya Samyukta; Singh, Vishal; Manikandan, M Sabarimalai; Ramkumar, Barathram

2015-08-01

In this Letter, the authors present a unified framework for fall event detection and classification using the cumulants extracted from the acceleration (ACC) signals acquired using a single waist-mounted triaxial accelerometer. The main objective of this Letter is to find suitable representative cumulants and classifiers in effectively detecting and classifying different types of fall and non-fall events. It was discovered that the first level of the proposed hierarchical decision tree algorithm implements fall detection using fifth-order cumulants and support vector machine (SVM) classifier. In the second level, the fall event classification algorithm uses the fifth-order cumulants and SVM. Finally, human activity classification is performed using the second-order cumulants and SVM. The detection and classification results are compared with those of the decision tree, naive Bayes, multilayer perceptron and SVM classifiers with different types of time-domain features including the second-, third-, fourth- and fifth-order cumulants and the signal magnitude vector and signal magnitude area. The experimental results demonstrate that the second- and fifth-order cumulant features and SVM classifier can achieve optimal detection and classification rates of above 95%, as well as the lowest false alarm rate of 1.03%.

Further developments of series-connected superconducting tunnel junction to radiation detection

NASA Astrophysics Data System (ADS)

Kurakado, Masahiko; Ohsawa, Daisuke; Katano, Rintaro; Ito, Shin; Isozumi, Yasuhito

1997-10-01

One of the promising radiation detection devices for various practical applications is the series-connected superconducting tunnel junction (STJ) detector. In this article, interesting topics of the detectors are described since our previous work: e.g., more than two order higher detection efficiency compared with single STJ detectors, high count rate detection, and position resolution. Detectors were cooled to 0.35-0.4 K by means of a convenient 3He cryostat. The 5.9 and 6.5 keV x rays from 55Fe are separated by a detector specially designed for x-ray detection. The possible count rate of the series-junction detector estimated from the shaping-time constant applied in the measurements is high, e.g., over 104 counts per second. A series-junction detector equipped with a position sensing mechanism has shown a position resolution of about 35 μm in a sensing area with a radius of 1.1 mm. The position resolution of series junctions improves the energy resolution. A new type series-connected STJ detector is also proposed, i.e., the dispersed multitrap series-junction detector, for further improvement of detection efficiency and energy resolution.

Detection of Delta9-tetrahydrocannabinol and amphetamine-type stimulants in oral fluid using the Rapid Stat point-of-collection drug-testing device.

PubMed

Röhrich, J; Zörntlein, S; Becker, J; Urban, R

2010-04-01

The Rapid Stat assay, a point-of-collection drug-testing device for detection of amphetamines, cannabinoids, cocaine, opiates, methadone, and benzodiazepines in oral fluid, was evaluated for cannabis and amphetamine-type stimulants. The Rapid Stat tests (n = 134) were applied by police officers in routine traffic checks. Oral fluid and blood samples were analyzed using gas chromatography-mass spectrometry (GC-MS) for Delta(9)-tetrahydrocannabinol, amphetamine, methamphetamine, methylenedioxymethamphetamine, methylenedioxyethylamphetamine, and methylenedioxyamphetamine. The comparison of GC-MS analysis of oral fluid with the Rapid Stat results for cannabis showed a sensitivity of 85%, a specificity of 87%, and a total confirmation rate of 87%. When compared with serum, the sensitivity of the cannabis assay decreased to 71%, the specificity to 60%, and the total confirmation rate to 66%. These findings were possibly caused by an incorrect reading of the THC test results. Comparison of the Rapid Stat amphetamine assay with GC-MS in oral fluid showed a sensitivity of 94%, a specificity of 97%, and a total confirmation rate of 97%. Compared with serum, a sensitivity of 100%, a specificity of 90%, and a total confirmation rate of 92% was found. The amphetamine assay must, therefore, be regarded as satisfactory.

Comparison of algorithms of testing for use in automated evaluation of sensation.

PubMed

Dyck, P J; Karnes, J L; Gillen, D A; O'Brien, P C; Zimmerman, I R; Johnson, D M

1990-10-01

Estimates of vibratory detection threshold may be used to detect, characterize, and follow the course of sensory abnormality in neurologic disease. The approach is especially useful in epidemiologic and controlled clinical trials. We studied which algorithm of testing and finding threshold should be used in automatic systems by comparing among algorithms and stimulus conditions for the index finger of healthy subjects and for the great toe of patients with mild neuropathy. Appearance thresholds obtained by linear ramps increasing at a rate less than 4.15 microns/sec provided accurate and repeatable thresholds compared with thresholds obtained by forced-choice testing. These rates would be acceptable if only sensitive sites were studied, but they were too slow for use in automatic testing of insensitive parts. Appearance thresholds obtained by fast linear rates (4.15 or 16.6 microns/sec) overestimated threshold, especially for sensitive parts. Use of the mean of appearance and disappearance thresholds, with the stimulus increasing exponentially at rates of 0.5 or 1.0 just noticeable difference (JND) units per second, and interspersion of null stimuli, Békésy with null stimuli, provided accurate, repeatable, and fast estimates of threshold for sensitive parts. Despite the good performance of Békésy testing, we prefer forced choice for evaluation of the sensation of patients with neuropathy.

The use of a fully integrated electronic medical record to minimize cumulative lifetime radiation exposure from CT scanning to detect urinary tract calculi.

PubMed

Kohler, Steven W; Chen, Richard; Kagan, Alex; Helvey, Dustin W; Buccigrossi, David

2013-06-01

In order to determine the effects of implementation of an electronic medical record on rates of repeat computed tomography (CT) scanning in the emergency department (ED) setting, we analyzed the utilization of CT of the kidneys, ureters, and bladder (CT KUB) for the detection of urinary tract calculi for periods before and after the implementation of a hospital-wide electronic medical record system. Rates of repeat CT scanning within a 6-month period of previous scan were determined pre- and post-implementation and compared. Prior to implementation, there was a 6-month repeat rate of 6.2 % compared with the post-implementation period, which was associated with a 6-month repeat rate of 4.1 %. Statistical analysis using a two-sample, one-tailed t test for difference of means was associated with a p value of 0.00007. This indicates that the implementation of the electronic medical record system was associated with a 34 % decrease in 6-month repeat CT KUB scans. We conclude that the use of an electronic medical record can be associated with a decrease in utilization of unnecessary repeat CT imaging, leading to decreased cumulative lifetime risk for cancer in these patients and more efficient utilization of ED and radiologic resources.

Reduction in interval cancer rates following the introduction of two-view mammography in the UK breast screening programme

PubMed Central

Dibden, A; Offman, J; Parmar, D; Jenkins, J; Slater, J; Binysh, K; McSorley, J; Scorfield, S; Cumming, P; Liao, X-H; Ryan, M; Harker, D; Stevens, G; Rogers, N; Blanks, R; Sellars, S; Patnick, J; Duffy, S W

2014-01-01

Background: The introduction of two-view mammography at incident (subsequent) screens in the National Health Service Breast Screening Programme (NHSBSP) has led to an increased number of cancers detected at screen. However, the effect of two-view mammography on interval cancer rates has yet to be assessed. Methods: Routine screening and interval cancer data were collated from all screening programmes in the United Kingdom for women aged 50–64, screened between 1 April 2003 and 31 March 2005. Interval cancer rates were compared based on whether two-view mammography was in use at the last routine screen. Results: The reduction in interval cancers following screening using two-view mammography compared with one view was 0.68 per 1 000 women screened. Overall, this suggests the introduction of two-view mammography at incident screen was accompanied by a 15–20% reduction in interval cancer rates in the NHSBSP. Conclusion: The introduction of two-view mammography at incident screens is associated with a reduction in incidence of interval cancers. This is consistent with previous publications on a contemporaneous increase in screen-detected cancers. The results provide further evidence of the benefit of the use of two-view mammography at incident screens. PMID:24366303

Randomized, controlled trial of standard-definition white-light, high-definition white-light, and narrow-band imaging colonoscopy for the detection of colon polyps and prediction of polyp histology.

PubMed

Rastogi, Amit; Early, Dayna S; Gupta, Neil; Bansal, Ajay; Singh, Vikas; Ansstas, Michael; Jonnalagadda, Sreenivasa S; Hovis, Christine E; Gaddam, Srinivas; Wani, Sachin B; Edmundowicz, Steven A; Sharma, Prateek

2011-09-01

Missing adenomas and the inability to accurately differentiate between polyp histology remain the main limitations of standard-definition white-light (SD-WL) colonoscopy. To compare the adenoma detection rates of SD-WL with those of high-definition white-light (HD-WL) and narrow-band imaging (NBI) as well as the accuracy of predicting polyp histology. Multicenter, prospective, randomized, controlled trial. Two academic medical centers in the United States. Subjects undergoing screening or surveillance colonoscopy. Subjects were randomized to undergo colonoscopy with one of the following: SD-WL, HD-WL, or NBI. The proportion of subjects detected with adenomas, adenomas detected per subject, and the accuracy of predicting polyp histology real time. A total of 630 subjects were included. The proportion of subjects with adenomas was 38.6% with SD-WL compared with 45.7% with HD-WL and 46.2% with NBI (P = .17 and P = .14, respectively). Adenomas detected per subject were 0.69 with SD-WL compared with 1.12 with HD-WL and 1.13 with NBI (P = .016 and P = .014, respectively). HD-WL and NBI detected more subjects with flat and right-sided adenomas compared with SD-WL (all P values <.005). NBI had a superior sensitivity (90%) and accuracy (82%) to predict adenomas compared with SD-WL and HD-WL (all P values <.005). Academic medical centers with experienced endoscopists. There was no difference in the proportion of subjects with adenomas detected with SD-WL, HD-WL, and NBI. However, HD-WL and NBI detected significantly more adenomas per subject (>60%) compared with SD-WL. NBI had the highest accuracy in predicting adenomas in real time during colonoscopy. ( NCT 00614770.). Copyright © 2011 American Society for Gastrointestinal Endoscopy. Published by Mosby, Inc. All rights reserved.

Prospective study aiming to compare 2D mammography and tomosynthesis + synthesized mammography in terms of cancer detection and recall. From double reading of 2D mammography to single reading of tomosynthesis.

PubMed

Romero Martín, Sara; Raya Povedano, Jose Luis; Cara García, María; Santos Romero, Ana Luz; Pedrosa Garriguet, Margarita; Álvarez Benito, Marina

2018-06-01

To evaluate tomosynthesis compared with 2D-mammography in cancer detection and recalls in a screening-programme, and assess performing synthesized instead of 2D, and compare double reading of 2D with single reading of tomosynthesis. Women (age 50-69 years) participating in the screening-programme were included. 2D-mammography and tomosynthesis were performed. There were four reading models: 2D-mammography (first); 2D-mammography (second); tomosynthesis + synthesized (third); tomosynthesis + synthesized + 2D (fourth reading). Paired double reading of 2D (first+second) and tomosynthesis (third+fourth) were analysed. In 16,067 participants, there were 98 cancers and 1,196 recalls. Comparing double reading of 2D with single reading of tomosynthesis, there was an increase of 12.6 % in cancer detection with the third reading (p= 0.043) and 6.9 % with the fourth reading (p=0.210), and a decrease in recalls of 40.5 % (p<0.001) and 44.4 % (p<0.001), respectively. With double reading of both techniques, there was an increase in cancer detection of 17.4 % (p = 0.004) and a decrease in recalls of 12.5 % (p = 0.001) with tomosynthesis. Single reading of tomosynthesis plus synthesized increased cancer detection and decreased recalls compared with double reading 2D. 2D did not improve results when added to tomosynthesis. • Tomosynthesis increases cancer detection and decreases recall rates versus 2D mammography. • Synthesized-mammography avoids performing 2D, showing higher cancer detection. • Single reading of tomosynthesis + synthesized is feasible as a new practice.

Temporal Cytokine Profiles in Severely Burned Patients: A Comparison of Adults and Children

PubMed Central

Finnerty, Celeste C; Jeschke, Marc G; Herndon, David N; Gamelli, Richard; Gibran, Nicole; Klein, Matthew; Silver, Geoff; Arnoldo, Brett; Remick, Daniel; Tompkins, Ronald G

2008-01-01

A severe burn leads to hypermetabolism and catabolism resulting in compromised function and structural changes of essential organs. The release of cytokines has been implicated in this hypermetabolic response. The severity of the hypermetabolic response following burn injury increases with age, as does the mortality rate. Due to the relationship between the hypermetabolic and inflammatory responses, we sought to compare the plasma cytokine profiles following a severe burn in adults and in children. We enrolled 25 adults and 24 children who survived a flame burn covering more than 20% of total body surface area (TBSA). The concentrations of 22 cytokines were measured using the Linco multiplex array system (St. Charles, MO, USA). Large perturbations in the expression of pro- and anti-inflammatory cytokines were seen following thermal injury. During the first week following burn injury, IFN-γ, IL-10, IL-17, IL-4, IL-6, and IL-8 were detected at significantly higher levels in adults compared with children, P < 0.05. Significant differences were measured during the second week post-burn for IL-1β (higher in children) and IL-5 (higher in adults), P < 0.05. IL-18 was more abundant in children compared with adults during the third week post-burn, P < 0.05. Between post-burn d 21 and d 66, IL-1α was detected at higher concentrations in pediatric compared with adult patients, P < 0.05. Only GM-CSF expression was significantly different at all time points; it was detected at lower levels in pediatric patients, P < 0.05. Eotaxin, G-CSF, IL-13, IL-15, IP-10, MCP-1, and MIP-1α were detected at significantly different concentrations in adult compared with pediatric patients at multiple time points, P < 0.05. There were no differences in IL-12, IL-2, IL-7, or TNF levels in adult compared with pediatric burn patients at any of these time points. Following severe flame burns, the cytokine profiles in pediatric patients differ compared with those in adult patients, which may provide insight with respect to the higher morbidity rate in adults. Furthermore, the dramatic discrepancies observed in plasma cytokine detection between children and adults suggest that these two patient populations may benefit from different therapeutic interventions to achieve attenuation of the post-burn inflammatory response. PMID:18548133

Only a minority of sex chromosome abnormalities are detected by a national prenatal screening program for Down syndrome.

PubMed

Viuff, Mette Hansen; Stochholm, Kirstine; Uldbjerg, Niels; Nielsen, Birgitte Bruun; Gravholt, Claus Højbjerg

2015-10-01

How does a national prenatal screening program for Down syndrome (DS) perform in detecting sex chromosome abnormalities (SCAs)-Turner syndrome (TS), Klinefelter syndrome, 47,XXX and 47,XYY syndromes. The SCA detection rate resulting from DS screening was below 50% for all four groups of SCAs. The detection rates of SCAs are higher in countries with DS screening. TS is associated with greater nuchal translucency (NT) and lower pregnancy-associated plasma protein-A (PAPP-A). However, specific detection rates of SCAs using prenatal DS screening have not been determined. No clear trend in PAPP-A, free beta human chorionic gonadotropin (β-hCG) and NT has been found in the remaining SCAs. Several lines of inquiry suggest that it would be advantageous for individuals with SCA to be detected early in life, leading to prevention or treatment of accompanying conditions. There is limited information about pre- and perinatal status that distinguishes SCA embryogenesis from normal fetal development. A register-based case-control study from the Danish Central Cytogenetic Register (DCCR), cross-linked with the Danish Fetal Medicine Database (DFMD), was performed from 2008 to 2012. Groups of SCAs were compared with DS and then matched with non-SCA controls to assess differences between these groups in prenatal markers and birth outcomes. We included cases with prenatal and post-natal SCA karyotypes (n = 213), DS (n = 802) and 168 056 controls. We screened 275 037 individuals examined prenatally. We retrieved information regarding maternal age, NT, β-hCG and PAPP-A, as well as details regarding maternal and newborn characteristics. The DS screening procedure detected 87 per 100 000 TS (42% of expected), 19 per 100 000 Klinefelter syndrome (13% of expected), 16 per 100 000 47,XXX (16% of cases) and 5 per 100 000 47,XYY (5% of expected) SCAs, with an overall detection rate of 27%. Compared with controls, all four SCA groups showed significantly higher NT and lower PAPP-A compared with controls (all P < 0.01) and similar to DS. The legal abortion rate was high for all four syndromes (47,XXX: 24%; 47,XYY: 29%; Klinefelter syndrome: 48%, TS: 84%). For SCA fetuses carried to term, only TS fetuses had consistently lower birthweights and placenta weights than non-SCA controls (both P = 0.0001). A few SCA cases localized in DCCR could not be found in DFMD (n = 16). Controls were matched on sex of the fetus of cases, meaning that all electively aborted fetuses (before week 12) were excluded, possibly reducing the diversity in the control group. We were not able to localize all diagnosed cases of SCA and DS in DFMD. Although these cases were present in DCCR, we were not able to account for the discrepancy. In addition, we suspect that several SCA children have not been diagnosed yet and future post-natal diagnosis of these cases would reduce the diagnostic yield reported here even further. The prenatal detection rate is below 50% for all SCAs. The approach used for detecting DS cannot be extended to also include SCAs. In addition, all SCAs have low PAPP-A and increased NT, thus probably reflecting an abnormal embryogenesis. Growth retardation of TS fetuses is if anything more pronounced than previously reported, both when evaluating fetus and placenta. This study received support from Aarhus University and the Novo Nordisk Foundation. The authors have no competing interests that may be relevant to the study. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Trauma and PTSD rates in an irish psychiatric population

PubMed Central

Wilson, Fiona E; Hennessy, Eilis; Dooley, Barbara; Kelly, Brendan D; Ryan, Dermot A

2013-01-01

Although Western mental health services are increasingly finding themselves concerned with assisting traumatized individuals migrating from other countries, trauma and posttraumatic stress disorder (PTSD) are under-detected and undiagnosed in psychiatric populations. This study examined and compared rates of traumatic experiences, frequency of traumatic events, trauma symptomatology levels, rates of torture, rates of PTSD and chart documentation of trauma and PTSD between (a) Irish and migrant service-users and (b) forced migrant and voluntary migrant service-users in Dublin, Ireland. Data were gathered from 178 psychiatric outpatients attending using a sociodemographic questionnaire, the Harvard Trauma Questionnaire-Revised Cambodian Version and the SCID-I/P. A substantial number of service-users had experienced at least one lifetime trauma (71.3%), and a high percentage of both the Irish (47.4%) and migrant groups (70.3%) of service-users had experienced two or more events. Overall, analyses comparing rates between Irish, forced migrant and voluntary migrant service-users found that forced migrants displayed more traumatic life events, posttraumatic symptoms, and higher levels of PTSD than their voluntary migrant and Irish counterparts, with over 50% experiencing torture prior to arrival in Ireland. The lifetime rate of PTSD in the overall sample was 15.7% but only 53.57% of cases were documented in patient charts. The results of this study are informative about the nature and extent of the problem of trauma and PTSD among migrant mental health service users as well as highlighting the under-detected levels of trauma among native-born service users. PMID:28228990

Behavioral training enhances cortical temporal processing in neonatally deafened juvenile cats

PubMed Central

Vollmer, Maike; Raggio, Marcia W.; Schreiner, Christoph E.

2011-01-01

Deaf humans implanted with a cochlear prosthesis depend largely on temporal cues for speech recognition because spectral information processing is severely impaired. Training with a cochlear prosthesis is typically required before speech perception shows improvement, suggesting that relevant experience modifies temporal processing in the central auditory system. We tested this hypothesis in neonatally deafened cats by comparing temporal processing in the primary auditory cortex (AI) of cats that received only chronic passive intracochlear electric stimulation (ICES) with cats that were also trained with ICES to detect temporally challenging trains of electric pulses. After months of chronic passive stimulation and several weeks of detection training in behaviorally trained cats, multineuronal AI responses evoked by temporally modulated ICES were recorded in anesthetized animals. The stimulus repetition rates that produced the maximum number of phase-locked spikes (best repetition rate) and 50% cutoff rate were significantly higher in behaviorally trained cats than the corresponding rates in cats that received only chronic passive ICES. Behavioral training restored neuronal temporal following ability to levels comparable with those recorded in naïve prior normal-hearing adult deafened animals. Importantly, best repetitition rates and cutoff rates were highest for neuronal clusters activated by the electrode configuration used in behavioral training. These results suggest that neuroplasticity in the AI is induced by behavioral training and perceptual learning in animals deprived of ordinary auditory experience during development and indicate that behavioral training can ameliorate or restore temporal processing in the AI of profoundly deaf animals. PMID:21543753

Improved detection of Pneumocystis jirovecii in upper and lower respiratory tract specimens from children with suspected pneumocystis pneumonia using real-time PCR: a prospective study

PubMed Central

2011-01-01

Background Pneumocystis pneumonia (PCP) is a major cause of hospitalization and mortality in HIV-infected African children. Microbiologic diagnosis relies predominantly on silver or immunofluorescent staining of a lower respiratory tract (LRT) specimens which are difficult to obtain in children. Diagnosis on upper respiratory tract (URT) specimens using PCR has been reported useful in adults, but data in children are limited. The main objectives of the study was (1) to compare the diagnostic yield of PCR with immunofluorescence (IF) and (2) to investigate the usefulness of upper compared to lower respiratory tract samples for diagnosing PCP in children. Methods Children hospitalised at an academic hospital with suspected PCP were prospectively enrolled. An upper respiratory sample (nasopharyngeal aspirate, NPA) and a lower respiratory sample (induced sputum, IS or bronchoalveolar lavage, BAL) were submitted for real-time PCR and direct IF for the detection of Pneumocystis jirovecii. A control group of children with viral lower respiratory tract infections were investigated with PCR for PCP. Results 202 children (median age 3.3 [inter-quartile range, IQR 2.2 - 4.6] months) were enrolled. The overall detection rate by PCR was higher than by IF [180/349 (52%) vs. 26/349 (7%) respectively; p < 0.0001]. PCR detected more infections compared to IF in lower respiratory tract samples [93/166 (56%) vs. 22/166 (13%); p < 0.0001] and in NPAs [87/183 (48%) vs. 4/183 (2%); p < 0.0001]. Detection rates by PCR on upper (87/183; 48%) compared with lower respiratory tract samples (93/166; 56%) were similar (OR, 0.71; 95% CI, 0.46 - 1.11). Only 2/30 (6.6%) controls were PCR positive. Conclusion Real-time PCR is more sensitive than IF for the detection of P. jirovecii in children with PCP. NPA samples may be used for diagnostic purposes when PCR is utilised. Wider implementation of PCR on NPA samples is warranted for diagnosing PCP in children. PMID:22123076

Constraints on Short, Hard Gamma-Ray Burst Beaming Angles from Gravitational Wave Observations

NASA Astrophysics Data System (ADS)

Williams, D.; Clark, J. A.; Williamson, A. R.; Heng, I. S.

2018-05-01

The first detection of a binary neutron star merger, GW170817, and an associated short gamma-ray burst confirmed that neutron star mergers are responsible for at least some of these bursts. The prompt gamma-ray emission from these events is thought to be highly relativistically beamed. We present a method for inferring limits on the extent of this beaming by comparing the number of short gamma-ray bursts (SGRBs) observed electromagnetically with the number of neutron star binary mergers detected in gravitational waves. We demonstrate that an observing run comparable to the expected Advanced LIGO (aLIGO) 2016–2017 run would be capable of placing limits on the beaming angle of approximately θ \\in (2\\buildrel{\\circ}\\over{.} 88,14\\buildrel{\\circ}\\over{.} 15), given one binary neutron star detection, under the assumption that all mergers produce a gamma-ray burst, and that SGRBs occur at an illustrative rate of {{ \\mathcal R }}grb}=10 {Gpc}}-3 {yr}}-1. We anticipate that after a year of observations with aLIGO at design sensitivity in 2020, these constraints will improve to θ \\in (8\\buildrel{\\circ}\\over{.} 10,14\\buildrel{\\circ}\\over{.} 95), under the same efficiency and SGRB rate assumptions.

Deficient Emotional Self-Regulation in Preschoolers With ADHD: Identification, Comorbidity, and Interpersonal Functioning.

PubMed

Melegari, Maria Grazia; Sacco, Roberto; Manzi, Barbara; Vittori, Elena; Persico, Antonio M

2016-01-07

This study aims to develop an age-adjusted Child Behavior Checklist- (CBCL) and Teacher Report Form (TRF)-based method for the detection of deficient emotional self-regulation (DESR) in preschoolers with ADHD and to assess its incidence, comorbidities, and consequences on interpersonal functioning. Eighty-six ADHD preschoolers and 104 controls were assessed using CBCL, TRF/1½ to 5, Psychiatric Interview With Preschool Age Psychiatric Assessment, Leiter-R, and ADHD rating scales. Greatest sensitivity and specificity were obtained applying slightly lower threshold scores compared with school-age children (CBCL: Anxiety/Depression [A/D] ≥ 59, Attention Problems [AP] ≥ 60, Aggression Behaviors [AB] ≥ 58; TRF: A/D ≥ 59, AP ≥ 60, AB ≥ 60). DESR was detected in 33/86 (38.4%) and in 16/54 (29.6%) ADHD preschoolers versus 2/104 (1.9%) controls using CBCL and TRF, respectively. DESR is associated with significantly greater comorbidity and impairment in interpersonal functioning. Among ADHD preschoolers, DESR (a) requires lower CBCL and TRF threshold scores for detection, compared with school-age children, (b) displays similar incidence rates, and (c) is associated with enhanced psychiatric comorbidity and interpersonal difficulties. © The Author(s) 2016.

Direct detection of sub-GeV dark matter with scintillating targets

DOE PAGES

Derenzo, Stephen; Essig, Rouven; Massari, Andrea; ...

2017-07-28

We suggest a novel experimental concept for detecting MeV-to-GeV-mass dark matter, in which the dark matter scatters off electrons in a scintillating target and produces a signal of one or a few photons. New large-area photodetectors are needed to measure the photon signal with negligible dark counts, which could be constructed from transition edge sensor (TES) or microwave kinetic inductance detector (MKID) technology. Alternatively, detecting two photons in coincidence may allow the use of conventional photodetectors like photomultiplier tubes. Here we describe why scintillators may have distinct advantages over other experiments searching for a low ionization signal from sub-GeV darkmore » matter, as there are fewer potential sources of spurious backgrounds. We discuss various target choices, but focus on calculating the expected dark matter-electron scattering rates in three scintillating crystals: sodium iodide (NaI), cesium iodide (CsI), and gallium arsenide (GaAs). Among these, GaAs has the lowest band gap (1.52 eV) compared to NaI (5.9 eV) or CsI (6.4 eV), which in principle allows it to probe dark matter masses as low as ~0.5 MeV, compared to ~1.5 MeV with NaI or CsI. We compare these scattering rates with those expected in silicon (Si) and germanium (Ge). The proposed experimental concept presents an important complementary path to existing efforts, and its potential advantages may make it the most sensitive direct-detection probe of dark matter down to MeV masses.« less

Direct detection of sub-GeV dark matter with scintillating targets

DOE Office of Scientific and Technical Information (OSTI.GOV)

Derenzo, Stephen; Essig, Rouven; Massari, Andrea

We suggest a novel experimental concept for detecting MeV-to-GeV-mass dark matter, in which the dark matter scatters off electrons in a scintillating target and produces a signal of one or a few photons. New large-area photodetectors are needed to measure the photon signal with negligible dark counts, which could be constructed from transition edge sensor (TES) or microwave kinetic inductance detector (MKID) technology. Alternatively, detecting two photons in coincidence may allow the use of conventional photodetectors like photomultiplier tubes. Here we describe why scintillators may have distinct advantages over other experiments searching for a low ionization signal from sub-GeV darkmore » matter, as there are fewer potential sources of spurious backgrounds. We discuss various target choices, but focus on calculating the expected dark matter-electron scattering rates in three scintillating crystals: sodium iodide (NaI), cesium iodide (CsI), and gallium arsenide (GaAs). Among these, GaAs has the lowest band gap (1.52 eV) compared to NaI (5.9 eV) or CsI (6.4 eV), which in principle allows it to probe dark matter masses as low as ~0.5 MeV, compared to ~1.5 MeV with NaI or CsI. We compare these scattering rates with those expected in silicon (Si) and germanium (Ge). The proposed experimental concept presents an important complementary path to existing efforts, and its potential advantages may make it the most sensitive direct-detection probe of dark matter down to MeV masses.« less

Distribution and seasonal differences in Pacific Lamprey and Lampetra spp eDNA across 18 Puget Sound watersheds

USGS Publications Warehouse

Ostberg, Carl O.; Chase, Dorothy M.; Hayes, Michael C.; Duda, Jeffrey J.

2018-01-01

Lampreys have a worldwide distribution, are functionally important to ecological communities and serve significant roles in many cultures. In Pacific coast drainages of North America, lamprey populations have suffered large declines. However, lamprey population status and trends within many areas of this region are unknown and such information is needed for advancing conservation goals. We developed two quantitative PCR-based, aquatic environmental DNA (eDNA) assays for detection of Pacific Lamprey (Entosphenus tridentatus) and Lampetra spp, using locked nucleic acids (LNAs) in the probe design. We used these assays to characterize the spatial distribution of lamprey in 18 watersheds of Puget Sound, Washington, by collecting water samples in spring and fall. Pacific Lamprey and Lampetraspp were each detected in 14 watersheds and co-occurred in 10 watersheds. Lamprey eDNA detection rates were much higher in spring compared to fall. Specifically, the Pacific Lamprey eDNA detection rate was 3.5 times higher in spring and the Lampetra spp eDNA detection rate was 1.5 times higher in spring even though larval lamprey are present in streams year-round. This significant finding highlights the importance of seasonality on eDNA detection. Higher stream discharge in the fall likely contributed to reduced eDNA detection rates, although seasonal life history events may have also contributed. These eDNA assays differentiate Pacific Lamprey and Lampetra spp across much of their range along the west coast of North America. Sequence analysis indicates the Pacific Lamprey assay also targets other Entosphenus spp and indicates the Lampetra spp assay may have limited or no capability of detecting Lampetra in some locations south of the Columbia River Basin. Nevertheless, these assays will serve as a valuable tool for resource managers and have direct application to lamprey conservation efforts, such as mapping species distributions, occupancy modeling, and monitoring translocations and reintroductions.

Distribution and seasonal differences in Pacific Lamprey and Lampetra spp eDNA across 18 Puget Sound watersheds

PubMed Central

Hayes, Michael C.; Duda, Jeffrey J.

2018-01-01

Lampreys have a worldwide distribution, are functionally important to ecological communities and serve significant roles in many cultures. In Pacific coast drainages of North America, lamprey populations have suffered large declines. However, lamprey population status and trends within many areas of this region are unknown and such information is needed for advancing conservation goals. We developed two quantitative PCR-based, aquatic environmental DNA (eDNA) assays for detection of Pacific Lamprey (Entosphenus tridentatus) and Lampetra spp, using locked nucleic acids (LNAs) in the probe design. We used these assays to characterize the spatial distribution of lamprey in 18 watersheds of Puget Sound, Washington, by collecting water samples in spring and fall. Pacific Lamprey and Lampetra spp were each detected in 14 watersheds and co-occurred in 10 watersheds. Lamprey eDNA detection rates were much higher in spring compared to fall. Specifically, the Pacific Lamprey eDNA detection rate was 3.5 times higher in spring and the Lampetra spp eDNA detection rate was 1.5 times higher in spring even though larval lamprey are present in streams year-round. This significant finding highlights the importance of seasonality on eDNA detection. Higher stream discharge in the fall likely contributed to reduced eDNA detection rates, although seasonal life history events may have also contributed. These eDNA assays differentiate Pacific Lamprey and Lampetra spp across much of their range along the west coast of North America. Sequence analysis indicates the Pacific Lamprey assay also targets other Entosphenus spp and indicates the Lampetra spp assay may have limited or no capability of detecting Lampetra in some locations south of the Columbia River Basin. Nevertheless, these assays will serve as a valuable tool for resource managers and have direct application to lamprey conservation efforts, such as mapping species distributions, occupancy modeling, and monitoring translocations and reintroductions. PMID:29576966

Does platelet-rich plasma have a favorable effect in the early stages of steroid-associated femoral head osteonecrosis in a rabbit model?

PubMed

Karakaplan, Mustafa; Gülabi, Deniz; Topgül, Haldun; Elmalı, Nurzat

2017-08-01

This study aims to investigate the effect of platelet-rich plasma (PRP) on femoral head osteonecrosis and compare it with bone marrow injection and core decompression. A total of 30 healthy, adult, male New Zealand white rabbits (mean weight 2.25±0.15 kg; range 2.0 to 2.5 kg) were used in the study. To create experimental osteonecrosis in all rabbits, 40 mg/kg methylprednisolone acetate was applied intramuscularly. Rabbits were randomly allocated into three groups with 10 rabbits in each: drilling group, PRP group, and bone marrow group. The non-drilled hips of the drilling group were identified as the control group. Rate of necrotic bone was lower in the PRP group compared to other groups. Highest rate of necrotic bone was detected in the control group. New bone formation rate was higher in the PRP group compared to other groups. Lowest new bone formation rate was determined in the control group. Inflammatory reaction rate was higher in the PRP group compared to other groups. Platelet-rich plasma injection may play a positive role in the treatment of steroid-associated osteonecrosis in a rabbit model.

Implementation of sobel method to detect the seed rubber plant leaves

NASA Astrophysics Data System (ADS)

Suyanto; Munte, J.

2018-03-01

This research was conducted to develop a system that can identify and recognize the type of rubber tree based on the pattern of leaves of the plant. The steps research are started with the identification of the image data acquisition, image processing, image edge detection and identification method template matching. Edge detection is using Sobel edge detection. Pattern recognition would detect image as input and compared with other images in a database called templates. Experiments carried out in one phase, identification of the leaf edge, using a rubber plant leaf image 14 are superior and 5 for each type of test images (clones) of the plant. From the experimental results obtained by the recognition rate of 91.79%.

Detecting Image Splicing Using Merged Features in Chroma Space

PubMed Central

Liu, Guangjie; Dai, Yuewei

2014-01-01

Image splicing is an image editing method to copy a part of an image and paste it onto another image, and it is commonly followed by postprocessing such as local/global blurring, compression, and resizing. To detect this kind of forgery, the image rich models, a feature set successfully used in the steganalysis is evaluated on the splicing image dataset at first, and the dominant submodel is selected as the first kind of feature. The selected feature and the DCT Markov features are used together to detect splicing forgery in the chroma channel, which is convinced effective in splicing detection. The experimental results indicate that the proposed method can detect splicing forgeries with lower error rate compared to the previous literature. PMID:24574877

Detecting image splicing using merged features in chroma space.

PubMed

Xu, Bo; Liu, Guangjie; Dai, Yuewei

2014-01-01

Image splicing is an image editing method to copy a part of an image and paste it onto another image, and it is commonly followed by postprocessing such as local/global blurring, compression, and resizing. To detect this kind of forgery, the image rich models, a feature set successfully used in the steganalysis is evaluated on the splicing image dataset at first, and the dominant submodel is selected as the first kind of feature. The selected feature and the DCT Markov features are used together to detect splicing forgery in the chroma channel, which is convinced effective in splicing detection. The experimental results indicate that the proposed method can detect splicing forgeries with lower error rate compared to the previous literature.

Texture based segmentation method to detect atherosclerotic plaque from optical tomography images

NASA Astrophysics Data System (ADS)

Prakash, Ammu; Hewko, Mark; Sowa, Michael; Sherif, Sherif

2013-06-01

Optical coherence tomography (OCT) imaging has been widely employed in assessing cardiovascular disease. Atherosclerosis is one of the major cause cardio vascular diseases. However visual detection of atherosclerotic plaque from OCT images is often limited and further complicated by high frame rates. We developed a texture based segmentation method to automatically detect plaque and non plaque regions from OCT images. To verify our results we compared them to photographs of the vascular tissue with atherosclerotic plaque that we used to generate the OCT images. Our results show a close match with photographs of vascular tissue with atherosclerotic plaque. Our texture based segmentation method for plaque detection could be potentially used in clinical cardiovascular OCT imaging for plaque detection.

Camera trap placement and the potential for bias due to trails and other features

PubMed Central

Forrester, Tavis D.

2017-01-01

Camera trapping has become an increasingly widespread tool for wildlife ecologists, with large numbers of studies relying on photo capture rates or presence/absence information. It is increasingly clear that camera placement can directly impact this kind of data, yet these biases are poorly understood. We used a paired camera design to investigate the effect of small-scale habitat features on species richness estimates, and capture rate and detection probability of several mammal species in the Shenandoah Valley of Virginia, USA. Cameras were deployed at either log features or on game trails with a paired camera at a nearby random location. Overall capture rates were significantly higher at trail and log cameras compared to their paired random cameras, and some species showed capture rates as much as 9.7 times greater at feature-based cameras. We recorded more species at both log (17) and trail features (15) than at their paired control cameras (13 and 12 species, respectively), yet richness estimates were indistinguishable after 659 and 385 camera nights of survey effort, respectively. We detected significant increases (ranging from 11–33%) in detection probability for five species resulting from the presence of game trails. For six species detection probability was also influenced by the presence of a log feature. This bias was most pronounced for the three rodents investigated, where in all cases detection probability was substantially higher (24.9–38.2%) at log cameras. Our results indicate that small-scale factors, including the presence of game trails and other features, can have significant impacts on species detection when camera traps are employed. Significant biases may result if the presence and quality of these features are not documented and either incorporated into analytical procedures, or controlled for in study design. PMID:29045478

Camera trap placement and the potential for bias due to trails and other features.

PubMed

Kolowski, Joseph M; Forrester, Tavis D

2017-01-01

Camera trapping has become an increasingly widespread tool for wildlife ecologists, with large numbers of studies relying on photo capture rates or presence/absence information. It is increasingly clear that camera placement can directly impact this kind of data, yet these biases are poorly understood. We used a paired camera design to investigate the effect of small-scale habitat features on species richness estimates, and capture rate and detection probability of several mammal species in the Shenandoah Valley of Virginia, USA. Cameras were deployed at either log features or on game trails with a paired camera at a nearby random location. Overall capture rates were significantly higher at trail and log cameras compared to their paired random cameras, and some species showed capture rates as much as 9.7 times greater at feature-based cameras. We recorded more species at both log (17) and trail features (15) than at their paired control cameras (13 and 12 species, respectively), yet richness estimates were indistinguishable after 659 and 385 camera nights of survey effort, respectively. We detected significant increases (ranging from 11-33%) in detection probability for five species resulting from the presence of game trails. For six species detection probability was also influenced by the presence of a log feature. This bias was most pronounced for the three rodents investigated, where in all cases detection probability was substantially higher (24.9-38.2%) at log cameras. Our results indicate that small-scale factors, including the presence of game trails and other features, can have significant impacts on species detection when camera traps are employed. Significant biases may result if the presence and quality of these features are not documented and either incorporated into analytical procedures, or controlled for in study design.

Ultrasensitive SERS Flow Detector Using Hydrodynamic Focusing

PubMed Central

Negri, Pierre; Jacobs, Kevin T.; Dada, Oluwatosin O.; Schultz, Zachary D.

2013-01-01

Label-free, chemical specific detection in flow is important for high throughput characterization of analytes in applications such as flow injection analysis, electrophoresis, and chromatography. We have developed a surface-enhanced Raman scattering (SERS) flow detector capable of ultrasensitive optical detection on the millisecond time scale. The device employs hydrodynamic focusing to improve SERS detection in a flow channel where a sheath flow confines analyte molecules eluted from a fused silica capillary over a planar SERS-active substrate. Increased analyte interactions with the SERS substrate significantly improve detection sensitivity. The performance of this flow detector was investigated using a combination of finite element simulations, fluorescence imaging, and Raman experiments. Computational fluid dynamics based on finite element analysis was used to optimize the flow conditions. The modeling indicates that a number of factors, such as the capillary dimensions and the ratio of the sheath flow to analyte flow rates, are critical for obtaining optimal results. Sample confinement resulting from the flow dynamics was confirmed using wide-field fluorescence imaging of rhodamine 6G (R6G). Raman experiments at different sheath flow rates showed increased sensitivity compared with the modeling predictions, suggesting increased adsorption. Using a 50-millisecond acquisitions, a sheath flow rate of 180 μL/min, and a sample flow rate of 5 μL/min, a linear dynamic range from nanomolar to micromolar concentrations of R6G with a LOD of 1 nM is observed. At low analyte concentrations, rapid analyte desorption is observed, enabling repeated and high-throughput SERS detection. The flow detector offers substantial advantages over conventional SERS-based assays such as minimal sample volumes and high detection efficiency. PMID:24074461

Lightning on Jupiter - Rate, energetics, and effects

NASA Technical Reports Server (NTRS)

Lewis, J. S.

1980-01-01

Voyager data on the optical and radio-frequency detection of lightning discharges in the atmosphere of Jupiter suggest a stroke rate significantly lower than on the earth. The efficiency of conversion of atmospheric convective energy flux into lightning is almost certainly less than on the earth, probably near 10 to the -7th rather than the terrestrial value of 10 to the -4th. At this level the rate of production of complex organic molecules by lightning and by thunder shock waves is negligible compared to the rates of known photochemical processes for forming colored inorganic solids.

Ultrasound guided aspiration of hydrosalpinx fluid versus salpingectomy in the management of patients with ultrasound visible hydrosalpinx undergoing IVF-ET: a randomized controlled trial.

PubMed

Fouda, Usama M; Sayed, Ahmed M; Abdelmoty, Hatem I; Elsetohy, Khaled A

2015-01-01

The aim of this study was to compare the efficacy of ultrasound guided aspiration of hydrosalpinx fluid at the time of oocyte retrieval with salpingectomy in the management of patients with ultrasound visible hydrosalpinx undergoing IVF-ET. One hundred and sixty patients with ultrasound visible hydrosalpinx were randomized into salpingectomy group and aspiration group using computer generated randomization list and sequentially numbered sealed envelopes containing allocation information written on a card. The clinical pregnancy rate per started cycle and the implantation rate were non- significantly higher in the salpingectomy group compared with the aspiration group [40% vs. 27.5% (p value = 0.132) and 18.95% vs. 12.82% (p value =0.124), respectively]. In the aspiration group, 34.21% of patients had rapid re-accumulation of the hydrosalpinx fluid (i.e. within first two weeks after embryo transfer). Whereas, the clinical pregnancy rate per transfer cycle and the implantation rate were significantly higher in salpingectomy group compared with the subgroup of patients with rapid re-accumulation of hydrosalpinx fluid [42.67% vs. 19.23% (p value = 0.036) and 18.95% vs. 7.58% (p value = 0.032), respectively], no significant differences were detected between the salpingectomy group and the subgroup of patients with no re-accumulation of hydrosalpinx fluid (42.67% vs. 34% (p value = 0.356) and 18.95% vs. 15.5% (p value = 0.457), respectively). The small sample size could be the cause of failure of detecting significant increase in implantation and pregnancy rates in salpingectomy group compared with aspiration group. Further larger randomized controlled trials are needed to determine whether salpingectomy is more effective than aspiration of hydrosalpinx fluid or not. Moreover, the data presented in this study suggested that rapid re-accumulation of hydrosalpinx fluid is an obstacle against successful implantation and the cause of lower success rate with ultrasound guided aspiration of hydrosalpinx fluid compared with salpingectomy. Clinical trials.gov ( NCT02008240 ), registered 8 December 2013.

Gender bias in under-five mortality in low/middle-income countries.

PubMed

Costa, Janaína Calu; da Silva, Inacio Crochemore Mohnsam; Victora, Cesar Gomes

2017-01-01

Due to biological reasons, boys are more likely to die than girls. The detection of gender bias requires knowing the expected relation between male and female mortality rates at different levels of overall mortality, in the absence of discrimination. Our objective was to compare two approaches aimed at assessing excess female under-five mortality rate (U5MR) in low/middle-income countries. We compared the two approaches using data from 60 Demographic and Health Surveys (2005-2014). The prescriptive approach compares observed mortality rates with historical patterns in Western societies where gender discrimination was assumed to be low or absent. The descriptive approach is derived from global estimates of all countries with available data, including those affected by gender bias. The prescriptive approach showed significant excess female U5MR in 20 countries, compared with only one country according to the descriptive approach. Nevertheless, both models showed similar country rankings. The 13 countries with the highest and the 10 countries with the lowest rankings were the same according to both approaches. Differences in excess female mortality among world regions were significant, but not among country income groups. Both methods are useful for monitoring time trends, detecting gender-based inequalities and identifying and addressing its causes. The prescriptive approach seems to be more sensitive in the identification of gender bias, but needs to be updated using data from populations with current-day structures of causes of death.

Food hygiene, deprivation, types of premises and rates of gastrointestinal illnesses in the UK.

PubMed

Collins, Brendan

2015-01-01

To understand more about the relationship between economic deprivation, types of premises, food hygiene scores and rates of gastrointestinal illness in the UK. Data were extracted from the UK Food Standards Agency for about 300 000 UK premises which had hygiene scores based on visits from local authority food safety officers. These scores were analysed by type of premises, deprivation and local authority. Local authority-level average scores were mapped and compared with rates of laboratory-detected gastrointestinal illness from the Health Protection Agency. UK. UK premises (n 311 458) from 341 local authority areas that sell or produce food. There was a modest but statistically significant relationship between average food hygiene score and deprivation, which was caused by deprived areas having more of the categories of premises with significantly lower hygiene scores; these were pub/club (n 40 525), restaurant/café/canteen (n 73 052), small retailer (n 42 932) and takeaway (n 36 708). No relationship was established between local authority average food hygiene scores and rates of laboratory-detected gastrointestinal illness; however, this result does not preclude a relationship between food hygiene and rates of gastrointestinal illnesses, as laboratory-detected illness rates make up only a small proportion of actual rates of illness in the community. Certain types of UK premises are more likely to have low hygiene scores, which means that they should be targeted more for enforcement. These types of premises are more prevalent in the most economically deprived areas.

Acoustic method respiratory rate monitoring is useful in patients under intravenous anesthesia.

PubMed

Ouchi, Kentaro; Fujiwara, Shigeki; Sugiyama, Kazuna

2017-02-01

Respiratory depression can occur during intravenous general anesthesia without tracheal intubation. A new acoustic method for respiratory rate monitoring, RRa ® (Masimo Corp., Tokyo, Japan), has been reported to show good reliability in post-anesthesia care and emergency units. The purpose of this study was to investigate the reliability of the acoustic method for measurement of respiratory rate during intravenous general anesthesia, as compared with capnography. Patients with dental anxiety undergoing dental treatment under intravenous anesthesia without tracheal intubation were enrolled in this study. Respiratory rate was recorded every 30 s using the acoustic method and capnography, and detectability of respiratory rate was investigated for both methods. This study used a cohort study design. In 1953 recorded respiratory rate data points, the number of detected points by the acoustic method (1884, 96.5 %) was significantly higher than that by capnography (1682, 86.1 %) (P < 0.0001). In the intraoperative period, there was a significant difference in the LOA (95 % limits of agreement of correlation between difference and average of the two methods)/ULLOA (under the lower limit of agreement) in terms of use or non-use of a dental air turbine (P < 0.0001). In comparison between capnography, the acoustic method is useful for continuous monitoring of respiratory rate in spontaneously breathing subjects undergoing dental procedures under intravenous general anesthesia. However, the acoustic method might not accurately detect in cases in with dental air turbine.

A face in a (temporal) crowd.

PubMed

Hacker, Catrina M; Meschke, Emily X; Biederman, Irving

2018-03-20

Familiar objects, specified by name, can be identified with high accuracy when embedded in a rapidly presented sequence of images at rates exceeding 10 images/s. Not only can target objects be detected at such brief presentation rates, they can also be detected under high uncertainty, where their classification is defined negatively, e.g., "Not a Tool." The identification of a familiar speaker's voice declines precipitously when uncertainty is increased from one to a mere handful of possible speakers. Is the limitation imposed by uncertainty, i.e., the number of possible individuals, a general characteristic of processes for person individuation such that the identifiability of a familiar face would undergo a similar decline with uncertainty? Specifically, could the presence of an unnamed celebrity, thus any celebrity, be detected when presented in a rapid sequence of unfamiliar faces? If so, could the celebrity be identified? Despite the markedly greater physical similarity of faces compared to objects that are, say, not tools, the presence of a celebrity could be detected with moderately high accuracy (∼75%) at rates exceeding 7 faces/s. False alarms were exceedingly rare as almost all the errors were misses. Detection accuracy by moderate congenital prosopagnosics was lower than controls, but still well above chance. Given the detection of the presence of a celebrity, all subjects were almost always able to identify that celebrity, providing no role for a covert familiarity signal outside of awareness. Copyright © 2018 Elsevier Ltd. All rights reserved.

[Establishment of animal model for Pneumocystis carinii and study on etiological and molecular biological detection technology].

PubMed

Tian, Li-guang; Ai, Lin; Chu, Yan-hong; Wu, Xiu-ping; Cai, Yu-chun; Chen, Zhuo; Chen, Shao-hong; Chen, Jia-xu

2015-04-01

To establish an animal model for Pneumocystis pneumonia (PCP) and to study the etiological and molecular biological technology for PCP detection. SD and Wistar rats were divided into experimental and control groups randomly. The animals in the experimental group were immunosuppressed by subcutaneous injection with dexamethasone 2 mg per time per rat, twice a week, while those in the control group underwent the same way of injection with physiological saline simultaneously. After the induction for 8 weeks, all the rats were killed and their bronchoalveolar lavage fluid (BALF) and lung tissues were collected for smear making and microscopic detection. Meanwhile, the BALF samples were detected by PCR, and the products were sequenced and compared with rat source PCP in GenBank. A total of 34 samples of lung tissue and BALF were observed. The etiological detection showed that the infection rates of the rats in the experimental and control groups were 29.2% (7/24) and 0, respectively. In the experimental group, the infection rates of SD and Wistar rats were 25.0% (3/12) and 33.3% (4/12), respectively, and the difference between them was not statistically significant (P = 0.31). The positive detection rates of the lung smears and BALF from SD rats in the experimental group were 25.0% (3/12) and 16.7% (2/12), respectively, while those in Wistar rats in the experimental group were 33.3% (4/12) and 16.7% (2/12), respectively, and there were no statistically significant difference between them (P = 0.34, 0.24). A total of 28 samples of BALF were detected by PCR, and the positive detection rates of rats in the experimental group and control group were 91.7% (26/28) and 0, respectively. The sequence analysis of the PCR products showed that it shared 100% homology with the genes of rat source PCP in Gen Bank (JX499145, GU133622 and EF646865). The animal model of PCP can be established by subcutaneous injection with dexamethasone. As animal models, there are no significant difference between SD rats and Wistar rats. PCR method is suitable for PCP detection at the early stage of infection, while etiological detection with high missing rate is not a right option.

GBM Observations of Terrestrial Gamma-Ray Flashes

NASA Technical Reports Server (NTRS)

Briggs, M. S.; Fishman, G. J.; Connaughton, V.; Bhat, P. N.; Paciesas, W. S.; Preece, R. D.; Wilson-Hodge, C.; Chaplin, V. L.; Kippen, R. M.; vonKienlin, A.;

Fermi detection of a luminous γ-ray pulsar in a globular cluster.

PubMed

2011-11-25

We report on the Fermi Large Area Telescope's detection of γ-ray (>100 mega-electron volts) pulsations from pulsar J1823-3021A in the globular cluster NGC 6624 with high significance (~7 σ). Its γ-ray luminosity, L(γ) = (8.4 ± 1.6) × 10(34) ergs per second, is the highest observed for any millisecond pulsar (MSP) to date, and it accounts for most of the cluster emission. The nondetection of the cluster in the off-pulse phase implies that it contains <32 γ-ray MSPs, not ~100 as previously estimated. The γ-ray luminosity indicates that the unusually large rate of change of its period is caused by its intrinsic spin-down. This implies that J1823-3021A has the largest magnetic field and is the youngest MSP ever detected and that such anomalous objects might be forming at rates comparable to those of the more normal MSPs.

The Performance of the Four Anaerobic Blood Culture Bottles BacT/ALERT-FN, -FN Plus, BACTEC-Plus and -Lytic in Detection of Anaerobic Bacteria and Identification by Direct MALDI-TOF MS

PubMed Central

Almuhayawi, Mohammed; Altun, Osman; Abdulmajeed, Adam Dilshad; Ullberg, Måns; Özenci, Volkan

2015-01-01

Detection and identification of anaerobic bacteria in blood cultures (BC) is a well-recognized challenge in clinical microbiology. We studied 100 clinical anaerobic BC isolates to evaluate the performance of BacT/ALERT-FN, -FN Plus (BioMérieux), BACTEC-Plus and -Lytic (Becton Dickinson BioSciences) BC bottles in detection and time to detection (TTD) of anaerobic bacteria. BACTEC Lytic had higher detection rate (94/100, 94%) than BacT/ALERT FN Plus (80/100, 80%) (p<0.01) in the studied material. There was no significant difference in detection of anaerobic bacteria among the remaining bottle types. The 67 anaerobic bacteria that signalled positive in all four bottle types were analyzed to compare the time to detection (TTD) and isolates were directly identified by MALDI-TOF MS. There was a significant difference in TTD among the four bottle types (p<0.0001). The shortest median TTD was 18 h in BACTEC Lytic followed by BacT/ALERT FN (23.5 h), BACTEC Plus (27 h) and finally BacT/ALERT FN Plus (38 h) bottles. In contrast, MALDI-TOF MS performed similarly in all bottle types with accurate identification in 51/67 (76%) BacT/ALERT FN, 51/67 (76%) BacT/ALERT FN Plus, 53/67 (79%) BACTEC Plus and 50/67 (75%) BACTEC Lytic bottles. In conclusion, BACTEC Lytic bottles have significantly better detection rates and shorter TTD compared to the three other bottle types. The anaerobic BC bottles are equally suitable for direct MALDI-TOF MS for rapid and reliable identification of common anaerobic bacteria. Further clinical studies are warranted to investigate the performance of anaerobic BC bottles in detection of anaerobic bacteria and identification by direct MALDI-TOF MS. PMID:26554930

Breast cancer biology varies by method of detection and may contribute to overdiagnosis.

PubMed

Hayse, Brandon; Hooley, Regina J; Killelea, Brigid K; Horowitz, Nina R; Chagpar, Anees B; Lannin, Donald R

2016-08-01

Recently, it has been suggested that screening mammography may result in some degree of overdiagnosis (ie, detection of breast cancers that would never become clinically important within the lifespan of the patient). The extent and biology of these overdiagnosed cancers, however, is not well understood, and the effect of newer screening modalities on overdiagnosis is unknown. We performed a retrospective review of a prospectively collected database of breast cancers diagnosed at the Yale Breast Center from 2004-2014. The mode of initial presentation was categorized into 5 groups: screening mammogram, screening magnetic resonance imaging, screening ultrasonography, self-detected masses, and physician-detected masses. Compared with cancers presenting with masses, cancers detected by image-based screening were more likely to present with ductal carcinoma-in-situ or T1 cancers (P < .001). In addition to a simple stage shift, however, cancers detected by image-based screening were also more likely to be luminal and low-grade cancers; symptomatic cancers were more likely high-grade and triple-negative (P < .001, respectively). On a multivariate analysis, adjusting for age, race, and tumor size, cancers detected by mammogram, US, and magnetic resonance imaging had greater odds of being luminal (odds ratio 1.8, 95% confidence interval, 1.5-2.3; odds ratio 2.2, 95% confidence interval, 1.1-4.7; and odds ratio 4.7, 95% confidence interval, 2.1-10.6, respectively), and low-grade (odds ratio 2.2, 95% confidence interval, 1.6-2.9; odds ratio 4.9, 95% confidence interval, 2.7-8.9; and odds ratio 4.6, 95% confidence interval, 2.6-8.1, respectively) compared with cancers presenting with self-detected masses. Screening detects cancers with more indolent biology, potentially contributing to the observed rate of overdiagnosis. With magnetic resonance imaging and US being used more commonly for screening, the rate of overdiagnosis may increase further. Copyright © 2016. Published by Elsevier Inc.

The Performance of the Four Anaerobic Blood Culture Bottles BacT/ALERT-FN, -FN Plus, BACTEC-Plus and -Lytic in Detection of Anaerobic Bacteria and Identification by Direct MALDI-TOF MS.

PubMed

Almuhayawi, Mohammed; Altun, Osman; Abdulmajeed, Adam Dilshad; Ullberg, Måns; Özenci, Volkan

2015-01-01

Detection and identification of anaerobic bacteria in blood cultures (BC) is a well-recognized challenge in clinical microbiology. We studied 100 clinical anaerobic BC isolates to evaluate the performance of BacT/ALERT-FN, -FN Plus (BioMérieux), BACTEC-Plus and -Lytic (Becton Dickinson BioSciences) BC bottles in detection and time to detection (TTD) of anaerobic bacteria. BACTEC Lytic had higher detection rate (94/100, 94%) than BacT/ALERT FN Plus (80/100, 80%) (p<0.01) in the studied material. There was no significant difference in detection of anaerobic bacteria among the remaining bottle types. The 67 anaerobic bacteria that signalled positive in all four bottle types were analyzed to compare the time to detection (TTD) and isolates were directly identified by MALDI-TOF MS. There was a significant difference in TTD among the four bottle types (p<0.0001). The shortest median TTD was 18 h in BACTEC Lytic followed by BacT/ALERT FN (23.5 h), BACTEC Plus (27 h) and finally BacT/ALERT FN Plus (38 h) bottles. In contrast, MALDI-TOF MS performed similarly in all bottle types with accurate identification in 51/67 (76%) BacT/ALERT FN, 51/67 (76%) BacT/ALERT FN Plus, 53/67 (79%) BACTEC Plus and 50/67 (75%) BACTEC Lytic bottles. In conclusion, BACTEC Lytic bottles have significantly better detection rates and shorter TTD compared to the three other bottle types. The anaerobic BC bottles are equally suitable for direct MALDI-TOF MS for rapid and reliable identification of common anaerobic bacteria. Further clinical studies are warranted to investigate the performance of anaerobic BC bottles in detection of anaerobic bacteria and identification by direct MALDI-TOF MS.

Risk of Interval Cancer in Fecal Immunochemical Test Screening Significantly Higher During the Summer Months: Results from the National Cancer Screening Program in Korea.

PubMed

Cha, Jae Myung; Suh, Mina; Kwak, Min Seob; Sung, Na Young; Choi, Kui Son; Park, Boyoung; Jun, Jae Kwan; Hwang, Sang-Hyun; Lee, Do-Hoon; Kim, Byung Chang; Lee, You Kyoung; Han, Dong Soo

2018-04-01

This study aimed to evaluate the impact of seasonal variations in climate on the performance of the fecal immunochemical test (FIT) in screening for colorectal cancer in the National Cancer Screening Program in Korea. Data were extracted from the National Cancer Screening Program databases for participants who underwent FIT between 2009 and 2010. We compared positivity rates, cancer detection rates, interval cancer rates, positive predictive value, sensitivity, and specificity for FIT during the spring, summer, fall, and winter seasons in Korea. In total, 4,788,104 FIT results were analyzed. FIT positivity rate was lowest during the summer months. In the summer, the positive predictive value of FIT was about 1.1 times (adjusted odds ratio (aOR) 1.08, 95% confidence interval (CI) 1.00-1.16) higher in the overall FIT group and about 1.3 times (aOR 1.29, 95% CI 1.10-1.50) higher in the quantitative FIT group, compared to those in the other seasons. Cancer detection rates, however, were similar regardless of season. Interval cancer risk was significantly higher in the summer for both the overall FIT group (aOR 1.16, 95% CI 1.07-1.27) and the quantitative FIT group (aOR 1.31, 95% CI 1.12-1.52). In addition, interval cancers in the rectum and distal colon were more frequently detected in the summer and autumn than in the winter. The positivity rate of FIT was lower in the summer, and the performance of the FIT screening program was influenced by seasonal variations in Korea. These results suggest that more efforts to reduce interval cancer during the summer are needed in population-based screening programs using FIT, particularly in countries with high ambient temperatures.

[Effect of CP Metronomic Chemotherapy on RPMI 8226 Cell Proli-feration and Notch1/NF-κB Signaling Pathway In Vitro].

PubMed

Guo, Lie-Ping; Zhou, Fan; Shi, Hao-Tian; Chen, Hai-Min; Lin, Chen-Hui; Chen, Xiao-Ling; Hou, Jian

2016-10-01

To investigate the effect of metronomic chemotherapy of low dose phosphoramide combined with prednisolone (CP metronomic chemotherapy) on proliferation and apoptosis of RPMI 8226 cells, and to explore its regulating effect on Notch1/NF-κB signaling pathways. Experiment was divided into the DMSO control group, and the phosphoramide mustard (PM) group, the prednisolone group, the phosphoramide mustard plus prednisolone group (the CP group). RPMI 8226 cells were treated with different drugs, CCK-8 method was used to detect cell proliferation, flow cytometry was used to detect the cell cycle and apoptosis, reverse transcription PCR was used to detect Notch1 and NF-κB mRNA expression level. Compared with DMSO control group, RPMI8226 cell proliferation inhibition rate in all the PM, prednisolone and CP groups increased significantly with prolonging of time (r of 0.994,0.996,0.999, respectively, P<0.001). And at the same time, the inhibitory rate of cell proliferation was significantly different; the cell inhibitory rate in PM group was lowest, that in CP group was highgest, that in prednissone group was intermediate (P<0.01). After 48 hours, compared with the DMSO control group, the G 1 /G 0 cell proportion in treatment group increased significantly, S phase cell proportion decreased significantly, especially in PM and CP groups. The G 2 /M phase cell proportion increased in PM group, while reduced in the prednisolone and the CP groups. After 48 hours, compared with the DMSO control group, RPMI 8226 cell apoptosis rate increased as follow: in PM, pre-dnisolone and CP group(P<0.01). After 48 hours, compared with the DMSO control group, Notch1 and NF-κB mRNA expression in the prednisolone, the PM and the CP group decreased significantly(P<0.001). CP metronomic chemotherapy can significantly reduce RPMI 8226 cell proliferation, promote RPMI 8226 cell apoptosis, arrest RPMI 8226 cells mainly in the G 1 /G 0 phase, and significantly reduce Notch1 and NF-κB expression levels. It is suggested that Notch1/NF-κB signaling pathways is involved in CP metronomic chemotherapy for MM.

Comparison of ASGARD and UFOCapture

NASA Technical Reports Server (NTRS)

Blaauw, Rhiannon C.; Cruse, Katherine S.

2011-01-01

The Meteoroid Environment Office is undertaking a comparison between UFOCapture/Analyzer and ASGARD (All Sky and Guided Automatic Realtime Detection). To accomplish this, video output from a Watec video camera on a 17 mm Schneider lens (25 degree field of view) was split and input into the two different meteor detection softwares. The purpose of this study is to compare the sensitivity of the two systems, false alarm rates and trajectory information, among other quantities. The important components of each software will be highlighted and comments made about the detection/rejection algorithms and the amount of user-labor required for each system.

Neyman Pearson detection of K-distributed random variables

NASA Astrophysics Data System (ADS)

Tucker, J. Derek; Azimi-Sadjadi, Mahmood R.

2010-04-01

In this paper a new detection method for sonar imagery is developed in K-distributed background clutter. The equation for the log-likelihood is derived and compared to the corresponding counterparts derived for the Gaussian and Rayleigh assumptions. Test results of the proposed method on a data set of synthetic underwater sonar images is also presented. This database contains images with targets of different shapes inserted into backgrounds generated using a correlated K-distributed model. Results illustrating the effectiveness of the K-distributed detector are presented in terms of probability of detection, false alarm, and correct classification rates for various bottom clutter scenarios.

First field trial of an immunoradiometric assay for the detection of malaria sporozoites in mosquitoes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, F.H.; Zavala, F.; Graves, P.M.

1984-07-01

An immunoradiometric assay (IRMA) using a monoclonal antibody to the major surface protein of Plasmodium falciparum sporozoites was used to assess the P. falciparum sporozoite rate in a West African population of Anopheles gambiae (s.1.). Unlike current dissection techniques, the IRMA could detect sporozoite antigen in dried as well as fresh mosquitoes. In a controlled comparison, the sensitivity of the IRMA was comparable that of the dissection technique. Additionally, the IRMA was species specific and quantitative. Sensitivity of the assay was sufficient to detect sporozoite infections resulting from the development of a single oocyst.

Design and rationale of the assessment of proper physiologic response with rate adaptive pacing driven by minute ventilation or accelerometer (APPROPRIATE) trial.

PubMed

Gilliam, F Roosevelt; Giudici, Michael; Benn, Andrew; Koplan, Bruce; Berg, Kellie Jean Chase; Kraus, Stacia Merkel; Stolen, Kira Q; Alvarez, Guy E; Hopper, Donald L; Wilkoff, Bruce L

2011-02-01

Rate-adaptive sensors are designed to restore a physiologic heart rate response to activity, in particular for patients that have chronotropic incompetence (CI). Limited data exist comparing two primary types of sensors; an accelerometer (XL) sensor which detects activity or motion and a minute ventilation (MV) sensor, which detects the product of respiration rate and tidal volume. The APPROPRIATE study will evaluate the MV sensor compared with the XL sensor for superiority in improving functional capacity (peak VO(2)) in pacemaker patients that have CI. This study is a double-blind, randomized, two-arm trial that will enroll approximately 1,000 pacemaker patients. Patients will complete a 6-min walk test at the 2-week visit to screen for potential CI. Those projected to have CI will advance to a 1-month visit. At the 1-month visit, final determination of CI will be done by completing a peak exercise treadmill test while the pacemaker is programmed to DDDR with the device sensors set to passive. Patients failing to meet the study criteria for CI will not continue further in the trial. Patients that demonstrate CI will be randomized to program their rate-adaptive sensors to either MV or XL in a 1:1 ratio. The rate-adaptive sensor will be optimized for each patient using a short walk to determine the appropriate response factor. At a 2-month visit, patients will complete a CPX test with the rate-adaptive sensors in their randomized setting.

Increased detection of precancerous cervical lesions with adjunctive dynamic spectral imaging.

PubMed

DeNardis, Sara A; Lavin, Philip T; Livingston, Jeff; Salter, William R; James-Patrick, Nanette; Papagiannakis, Emmanouil; Olson, Christopher G; Weinberg, Lori

2017-01-01

To validate, in US community-based colposcopy clinics, previous reports of increased detection of high-grade cervical intraepithelial neoplasia (CIN2+) with biopsies selected using dynamic spectral imaging (DSI) mapping after standard colposcopy. Cross-sectional observational study of 26 colposcopists across nine clinics recruiting consecutive colposcopy patients. Standard assessment with biopsy selections was completed before seeing the DSI map which was subsequently interpreted and used for additional biopsies per clinical judgment. Primary measure was the number of women with CIN2+ detected by DSI-assisted biopsies, over those detected by standard colposcopy biopsies. A total of 887 women were recruited. After exclusions, 881 women and 1,189 biopsies were analyzed. Standard biopsy detected 78 women with CIN2+ and DSI-assisted biopsies another 34, increasing the detection rate from 8.85% to 12.71% ( p =0.00016). This was achieved with 16.16% of DSI-assisted biopsies finding CIN2+ compared to 13.24% for the preceding standard biopsies. For secondary specificity analysis, 431 women had only

Increased detection of precancerous cervical lesions with adjunctive dynamic spectral imaging

PubMed Central

DeNardis, Sara A; Lavin, Philip T; Livingston, Jeff; Salter, William R; James-Patrick, Nanette; Papagiannakis, Emmanouil; Olson, Christopher G; Weinberg, Lori

2017-01-01

Objective To validate, in US community-based colposcopy clinics, previous reports of increased detection of high-grade cervical intraepithelial neoplasia (CIN2+) with biopsies selected using dynamic spectral imaging (DSI) mapping after standard colposcopy. Study design Cross-sectional observational study of 26 colposcopists across nine clinics recruiting consecutive colposcopy patients. Standard assessment with biopsy selections was completed before seeing the DSI map which was subsequently interpreted and used for additional biopsies per clinical judgment. Primary measure was the number of women with CIN2+ detected by DSI-assisted biopsies, over those detected by standard colposcopy biopsies. Results A total of 887 women were recruited. After exclusions, 881 women and 1,189 biopsies were analyzed. Standard biopsy detected 78 women with CIN2+ and DSI-assisted biopsies another 34, increasing the detection rate from 8.85% to 12.71% (p=0.00016). This was achieved with 16.16% of DSI-assisted biopsies finding CIN2+ compared to 13.24% for the preceding standard biopsies. For secondary specificity analysis, 431 women had only

Comparison of Color Fundus Photography, Infrared Fundus Photography, and Optical Coherence Tomography in Detecting Retinal Hamartoma in Patients with Tuberous Sclerosis Complex

PubMed Central

Bai, Da-Yong; Wang, Xu; Zhao, Jun-Yang; Li, Li; Gao, Jun; Wang, Ning-Li

2016-01-01

Background: A sensitive method is required to detect retinal hamartomas in patients with tuberous sclerosis complex (TSC). The aim of the present study was to compare the color fundus photography, infrared imaging (IFG), and optical coherence tomography (OCT) in the detection rate of retinal hamartoma in patients with TSC. Methods: This study included 11 patients (22 eyes) with TSC, who underwent color fundus photography, IFG, and spectral-domain OCT to detect retinal hamartomas. TSC1 and TSC2 mutations were tested in eight patients. Results: The mean age of the 11 patients was 8.0 ± 2.1 years. The mean spherical equivalent was −0.55 ± 1.42 D by autorefraction with cycloplegia. In 11 patients (22 eyes), OCT, infrared fundus photography, and color fundus photography revealed 26, 18, and 9 hamartomas, respectively. The predominant hamartoma was type I (55.6%). All the hamartomas that detected by color fundus photography or IFG can be detected by OCT. Conclusion: Among the methods of color fundus photography, IFG, and OCT, the OCT has higher detection rate for retinal hamartoma in TSC patients; therefore, OCT might be promising for the clinical diagnosis of TSC. PMID:27174333

Reproductive outcomes, including neonatal data, following sperm injection in men with obstructive and nonobstructive azoospermia: case series and systematic review

PubMed Central

Esteves, Sandro C; Agarwal, Ashok

2013-01-01

We compared pregnancy outcomes following intracytoplasmic sperm injection for the treatment of male infertility according to the type of azoospermia. First, we analyzed our data from 370 couples who underwent intracytoplasmic sperm injection using sperm from men with obstructive azoospermia and nonobstructive azoospermia, and the outcomes were compared to a group of 465 non-azoospermic infertile males. Then, we performed a systematic review of the published data on pregnancy and neonatal outcomes of children born after sperm injection using sperm from men with obstructive and nonobstructive azoospermia. Live birth rates were significantly lower in the nonobstructive azoospermia group (21.4%) compared with the obstructive azoospermia (37.5%) and ejaculated sperm (32.3%) groups. A total of 326 live births resulted in 427 babies born. Differences were not observed between the groups in gestational age, preterm birth, birth weight and low birth weight, although we noted a tendency towards poorer neonatal outcomes in the azoospermia categories. The overall perinatal death and malformation rates were 2.8% and 1.6%, respectively, and the results did not differ between the groups. We identified 20 published studies that directly compared pregnancy outcomes between obstructive azoospermia and nonobstructive azoospermia. Most of these studies were not designed to detect differences in live birth rates and had lower power to detect differences in less frequent outcomes, and the reporting of neonatal outcomes was unusual. The included studies reported either a decrease or no difference in pregnancy outcomes with intracytoplasmic sperm injection in cases of nonobstructive azoospermia and obstructive azoospermia. In general, no major differences were noted in short-term neonatal outcomes and congenital malformation rates between children from fathers with nonobstructive azoospermia and obstructive azoospermia. PMID:23503964

Neutron counting with cameras

DOE Office of Scientific and Technical Information (OSTI.GOV)

Van Esch, Patrick; Crisanti, Marta; Mutti, Paolo

2015-07-01

A research project is presented in which we aim at counting individual neutrons with CCD-like cameras. We explore theoretically a technique that allows us to use imaging detectors as counting detectors at lower counting rates, and transits smoothly to continuous imaging at higher counting rates. As such, the hope is to combine the good background rejection properties of standard neutron counting detectors with the absence of dead time of integrating neutron imaging cameras as well as their very good spatial resolution. Compared to Xray detection, the essence of thermal neutron detection is the nuclear conversion reaction. The released energies involvedmore » are of the order of a few MeV, while X-ray detection releases energies of the order of the photon energy, which is in the 10 KeV range. Thanks to advances in camera technology which have resulted in increased quantum efficiency, lower noise, as well as increased frame rate up to 100 fps for CMOS-type cameras, this more than 100-fold higher available detection energy implies that the individual neutron detection light signal can be significantly above the noise level, as such allowing for discrimination and individual counting, which is hard to achieve with X-rays. The time scale of CMOS-type cameras doesn't allow one to consider time-of-flight measurements, but kinetic experiments in the 10 ms range are possible. The theory is next confronted to the first experimental results. (authors)« less

Precise fabrication of a 5 nm graphene nanopore with a helium ion microscope for biomolecule detection

NASA Astrophysics Data System (ADS)

Deng, Yunsheng; Huang, Qimeng; Zhao, Yue; Zhou, Daming; Ying, Cuifeng; Wang, Deqiang

2017-01-01

We report a scalable method to fabricate high-quality graphene nanopores for biomolecule detection using a helium ion microscope (HIM). HIM milling shows promising capabilities for precisely controlling the size and shape, and may allow for the potential production of nanopores at wafer scale. Nanopores could be fabricated at different sizes ranging from 5 to 30 nm in diameter in few minutes. Compared with the current solid-state nanopore fabrication techniques, e.g. transmission electron microscopy, HIM is fast. Furthermore, we investigated the exposure-time dependence of graphene nanopore formation: the rate of pore expansion did not follow a simple linear relationship with exposure time, but a fast expansion rate at short exposure time and a slow rate at long exposure time. In addition, we performed biomolecule detection with our patterned graphene nanopore. The ionic current signals induced by 20-base single-stranded DNA homopolymers could be used as a basis for homopolymer differentiation. However, the charge interaction of homopolymer chains with graphene nanopores, and the conformations of homopolymer chains need to be further considered to improve the accuracy of discrimination.