Biased Competition in Visual Processing Hierarchies: A Learning Approach Using Multiple Cues.

PubMed

Gepperth, Alexander R T; Rebhan, Sven; Hasler, Stephan; Fritsch, Jannik

2011-03-01

In this contribution, we present a large-scale hierarchical system for object detection fusing bottom-up (signal-driven) processing results with top-down (model or task-driven) attentional modulation. Specifically, we focus on the question of how the autonomous learning of invariant models can be embedded into a performing system and how such models can be used to define object-specific attentional modulation signals. Our system implements bi-directional data flow in a processing hierarchy. The bottom-up data flow proceeds from a preprocessing level to the hypothesis level where object hypotheses created by exhaustive object detection algorithms are represented in a roughly retinotopic way. A competitive selection mechanism is used to determine the most confident hypotheses, which are used on the system level to train multimodal models that link object identity to invariant hypothesis properties. The top-down data flow originates at the system level, where the trained multimodal models are used to obtain space- and feature-based attentional modulation signals, providing biases for the competitive selection process at the hypothesis level. This results in object-specific hypothesis facilitation/suppression in certain image regions which we show to be applicable to different object detection mechanisms. In order to demonstrate the benefits of this approach, we apply the system to the detection of cars in a variety of challenging traffic videos. Evaluating our approach on a publicly available dataset containing approximately 3,500 annotated video images from more than 1 h of driving, we can show strong increases in performance and generalization when compared to object detection in isolation. Furthermore, we compare our results to a late hypothesis rejection approach, showing that early coupling of top-down and bottom-up information is a favorable approach especially when processing resources are constrained.

Optimization of programming parameters in children with the advanced bionics cochlear implant.

PubMed

Baudhuin, Jacquelyn; Cadieux, Jamie; Firszt, Jill B; Reeder, Ruth M; Maxson, Jerrica L

2012-05-01

Cochlear implants provide access to soft intensity sounds and therefore improved audibility for children with severe-to-profound hearing loss. Speech processor programming parameters, such as threshold (or T-level), input dynamic range (IDR), and microphone sensitivity, contribute to the recipient's program and influence audibility. When soundfield thresholds obtained through the speech processor are elevated, programming parameters can be modified to improve soft sound detection. Adult recipients show improved detection for low-level sounds when T-levels are set at raised levels and show better speech understanding in quiet when wider IDRs are used. Little is known about the effects of parameter settings on detection and speech recognition in children using today's cochlear implant technology. The overall study aim was to assess optimal T-level, IDR, and sensitivity settings in pediatric recipients of the Advanced Bionics cochlear implant. Two experiments were conducted. Experiment 1 examined the effects of two T-level settings on soundfield thresholds and detection of the Ling 6 sounds. One program set T-levels at 10% of most comfortable levels (M-levels) and another at 10 current units (CUs) below the level judged as "soft." Experiment 2 examined the effects of IDR and sensitivity settings on speech recognition in quiet and noise. Participants were 11 children 7-17 yr of age (mean 11.3) implanted with the Advanced Bionics High Resolution 90K or CII cochlear implant system who had speech recognition scores of 20% or greater on a monosyllabic word test. Two T-level programs were compared for detection of the Ling sounds and frequency modulated (FM) tones. Differing IDR/sensitivity programs (50/0, 50/10, 70/0, 70/10) were compared using Ling and FM tone detection thresholds, CNC (consonant-vowel nucleus-consonant) words at 50 dB SPL, and Hearing in Noise Test for Children (HINT-C) sentences at 65 dB SPL in the presence of four-talker babble (+8 signal-to-noise ratio). Outcomes were analyzed using a paired t-test and a mixed-model repeated measures analysis of variance (ANOVA). T-levels set 10 CUs below "soft" resulted in significantly lower detection thresholds for all six Ling sounds and FM tones at 250, 1000, 3000, 4000, and 6000 Hz. When comparing programs differing by IDR and sensitivity, a 50 dB IDR with a 0 sensitivity setting showed significantly poorer thresholds for low frequency FM tones and voiced Ling sounds. Analysis of group mean scores for CNC words in quiet or HINT-C sentences in noise indicated no significant differences across IDR/sensitivity settings. Individual data, however, showed significant differences between IDR/sensitivity programs in noise; the optimal program differed across participants. In pediatric recipients of the Advanced Bionics cochlear implant device, manually setting T-levels with ascending loudness judgments should be considered when possible or when low-level sounds are inaudible. Study findings confirm the need to determine program settings on an individual basis as well as the importance of speech recognition verification measures in both quiet and noise. Clinical guidelines are suggested for selection of programming parameters in both young and older children. American Academy of Audiology.

MCP-1 in urine as biomarker of disease activity in Systemic Lupus Erythematosus.

PubMed

Barbado, Julia; Martin, Debora; Vega, Luisa; Almansa, Raquel; Gonçalves, Lisbeth; Nocito, Mercedes; Jimeno, Antonio; Ortiz de Lejarazu, Raúl; Bermejo-Martin, Jesus F

2012-11-01

Conventional clinical parameters are not sensitive or specific enough for detecting ongoing disease activity in the Systemic Lupus Erythematosus (SLE). Measurement of cytokines in urine is an encouraging approach to detection of early flares in this disease. Here we have profiled 27 different cytokines, chemokines and celular growth factors in the urine of 48 patients previously diagnosed of SLE as potential biomarkers of disease activity. Correlation analysis with Bonferroni correction showed that MCP-1 was the only immune mediator which levels in urine correlated directly with the SLE Disease Activity Index 2000 (SLEDAI-2K) score (correlation coefficient, p): MCP-1 (0.45,0.003). MCP-1 correlated inversely with levels of C3 complement protein in serum (-0.50,0.001). MCP-1 showed significant higher levels in patients with severe disease activity in comparison with those exhibiting mild activity. Levels of this chemokine were also higher in patients with severe disease activity in comparison with patients with inactive disease and healthy controls. Areas under receiver operating characteristic curves (AUROC) for detection of severe disease (SLEDAI⩾8) was as follows for MCP-1: [AUROC, (IC95%), p]: [0.81 (0.65-0.96) 0.003]. In addition, MCP-1 showed a good result in the AUROC analysis for detecting renal involvement [0.70 (0.52-0.87) 0.050]. When correlation analysis were repeated excluding those patients with active renal disease (n=14), levels of MCP-1 in urine kept on showing a significant positive association with SLEDAI-2K score. In conclusion, multiplex-based cytokine profiling in urine demonstrated the superiority of MCP-1 over a wide range of cytokines as biomarker of disease activity in SLE. Copyright © 2012 Elsevier Ltd. All rights reserved.

Special-geometry proportional counters and techniques for detection of low-levels of X-rays and beta-particles

NASA Technical Reports Server (NTRS)

Gregory, J. C.

1976-01-01

The use and sensitivity of the multiwire proportional counter to detect Kr-85 in ambient air are examined. Data also cover monitoring beta and X-ray emitting radio nuclides at low activity levels. Results show the counter to have excellent properties for monitoring Kr-85 down to 0.0004 pCi cu/cm.

[Clinical value of combined determination of serum and pleural effusion level of CEA,CYFRA21-1, TPS in the diagnosis of lung cancer].

PubMed

Huang, Fang; Wang, Xiao-li; Yang, Lian; Yin, Bin-xia; Geng, Yan; Li, Ting-ting

2008-04-01

To study the clinical value of combined determination of carcinoembryonic antigen (CEA), cytokeratin-19-fragments (CYFRA21-1) and tissue polypeptide specific antigen (TPS) levels in both serum and pleural effusion in the diagnosis of lung cancer. The levels of CEA, CYFRA21-1 and TPS in serum and pleural effusion were measured in 78 patients with lung cancer and 45 patients with benign lung disease by using electrochemiluminescence and ELISA methods respectively. The levels of CEA, CYFRA21-1 and TPS in pleural effusion of patients with lung cancer were much higher than those with benign lung disease (P<0.01). The levels of CEA and TPS in serum of patients with lung cancer were much higher than those with benign lung disease (P<0.05, P<0.01). It was also found that the levels of these tumor markers in pleural effusion were higher and more sensitive than those in sera, especially TPS. TPS showed the highest sensitivity in single tumor marker detection, and TPS+CYFRA21-1+ CEA showed the highest sensitivity and accuracy in combined tumor marker detection for diagnosis of lung cancer in pleural effusion. The combined detection of CEA, CYFRA21-1 and TPS in pleural effusion showed higher sensitivity, better accuracy and higher clinical value than those in serum for diagnosis of lung cancer.

Deoxyribonucleic Acid Probes Analyses for the Detection of Periodontal Pathogens.

PubMed

Al Yahfoufi, Zoubeida; Hadchiti, Wahib; Berberi, Antoine

2015-09-01

In clinical microbiology several techniques have been used to identify bacteria. Recently, Deoxyribonucleic acid (DNA)-based techniques have been introduced to detect human microbial pathogens in periodontal diseases. Deoxyribonucleic acid probes can detect bacteria at a very low level if we compared with the culture methods. These probes have shown rapid and cost-effective microbial diagnosis, good sensitivity and specificity for some periodontal pathogens in cases of severe periodontitis. Eighty-five patients were recruited for the study. Twenty-one subjects ranging between 22 and 48 years of age fulfilled the inclusion and exclusion criteria. Seventy-eight samples became available for DNA probe analysis from the deepest pockets in each quadrant. All 21 patients showed positive results for Prevotella intermedia; also, Prevotella gingivalis was identified in 19 subjects, Aggregatibacter actinomycetemcomitans in 6 subjects. P. intermedia was diagnosed positive in 82% of the subgingival samples taken, 79% for P. gingivalis, and 23% for A. actinomycetemcomitans. This study shows a high frequency of putative periodontal pathogens by using DNA probe technology, which is semi-quantitative in this study. Deoxyribonucleic acid probes can detect bacteria at very low level about 10(3) which is below the detection level of culture methods. The detection threshold of cultural methods. The three types of bacteria can be detected rapidly with high sensitivity by using the DNA probe by general practitioners, and thus can help in the diagnosis process and the treatment.

[Clinical value of combined detection of LDH, TPS, CEA and beta2-MG in patients with non- Hodgkin's lymphoma].

PubMed

Chen, Wei; Luo, Rong-cheng; Fan, Wei-wen; Ma, Shu-dong

2006-02-01

To study the clinical value of combined detection of 4 tumor markers, namely lactic dehydrogenate (LDH), tissue polypeptide specific antigen (TPS), carcinoembryonic antigen (CEA) and beta2-microglobulin (beta2-MG) in patients with non-Hodgkin's lymphoma (NHL). The serum level of LDH was determined with automatic biochemical analyzer and TPS, CEA and beta2-MG levels were determined by enzyme-linked immumosorbent assay (ELISA) in 59 patients with NHL and 40 healthy adults. The levels of the 4 tumor markers were significantly higher in NHL patients than in the healthy control subjects (P<0.05). After chemotherapy, the serum levels of TPS and beta2-MG were significantly lowered in the patients who showed favorable response to the treatment (P<0.05), but the levels of LDH and CEA showed no significant change (P>0.05). The serum levels of LDH, TPS, CEA and beta2-MG in the patients in a stable or progressive phase did had no significant changes after chemotherapy (P>0.05). Combined detection of LDH, TPS, CEA and beta2-MG can be helpful to assist diagnosis of NHL and treatment evaluation.

Scene and human face recognition in the central vision of patients with glaucoma

PubMed Central

Aptel, Florent; Attye, Arnaud; Guyader, Nathalie; Boucart, Muriel; Chiquet, Christophe; Peyrin, Carole

2018-01-01

Primary open-angle glaucoma (POAG) firstly mainly affects peripheral vision. Current behavioral studies support the idea that visual defects of patients with POAG extend into parts of the central visual field classified as normal by static automated perimetry analysis. This is particularly true for visual tasks involving processes of a higher level than mere detection. The purpose of this study was to assess visual abilities of POAG patients in central vision. Patients were assigned to two groups following a visual field examination (Humphrey 24–2 SITA-Standard test). Patients with both peripheral and central defects and patients with peripheral but no central defect, as well as age-matched controls, participated in the experiment. All participants had to perform two visual tasks where low-contrast stimuli were presented in the central 6° of the visual field. A categorization task of scene images and human face images assessed high-level visual recognition abilities. In contrast, a detection task using the same stimuli assessed low-level visual function. The difference in performance between detection and categorization revealed the cost of high-level visual processing. Compared to controls, patients with a central visual defect showed a deficit in both detection and categorization of all low-contrast images. This is consistent with the abnormal retinal sensitivity as assessed by perimetry. However, the deficit was greater for categorization than detection. Patients without a central defect showed similar performances to the controls concerning the detection and categorization of faces. However, while the detection of scene images was well-maintained, these patients showed a deficit in their categorization. This suggests that the simple loss of peripheral vision could be detrimental to scene recognition, even when the information is displayed in central vision. This study revealed subtle defects in the central visual field of POAG patients that cannot be predicted by static automated perimetry assessment using Humphrey 24–2 SITA-Standard test. PMID:29481572

LC/DAD/ESI/MS method for the determination of imidacloprid, thiacloprid, and spinosad in olives and olive oil after field treatment.

PubMed

Angioni, Alberto; Porcu, Luciano; Pirisi, Filippo

2011-10-26

The behavior in the field and the transfer from olives to olive oil during the technological process of imidacloprid, thiacloprid, and spinosad were studied. The extraction method used was effective in extracting the analytes of interest, and no interfering peaks were detected in the chromatogram. The residue levels found in olives after treatment were 0.14, 0.04, and 0.30 mg/kg for imidacloprid, thiacloprid, and spinosad, respectively, far below the maximum residue levels (MRLs) set for these insecticides in EU. At the preharvest interval (PHI), no residue was detected for imidacloprid and thiacloprid, while spinosad showed a residue level of 0.04 mg/kg. The study of the effect of the technological process on pesticide transfer in olive oil showed that these insecticides tend to remain in the olive cake. The LC/DAD/ESI/MS method showed good performance with adequate recoveries ranging from 80 to 119% and good method limits of quantitation (LOQs) and of determination (LODs). No matrix effect was detected.

Ultrasensitive Detection of Shigella Species in Blood and Stool.

PubMed

Luo, Jieling; Wang, Jiapeng; Mathew, Anup S; Yau, Siu-Tung

2016-02-16

A modified immunosensing system with voltage-controlled signal amplification was used to detect Shigella in stool and blood matrixes at the single-digit CFU level. Inactivated Shigella was spiked in these matrixes and detected directly. The detection was completed in 78 min. Detection limits of 21 CFU/mL and 18 CFU/mL were achieved in stool and blood, respectively, corresponding to 2-7 CFUs immobilized on the detecting electrode. The outcome of the detection of extremely low bacterium concentration, i.e., below 100 CFU/mL, blood samples show a random nature. An analysis of the detection probabilities indicates the correlation between the sample volume and the success of detection and suggests that sample volume is critical for ultrasensitive detection of bacteria. The calculated detection limit is qualitatively in agreement with the empirically determined detection limit. The demonstrated ultrasensitive detection of Shigella on the single-digit CFU level suggests the feasibility of the direct detection of the bacterium in the samples without performing a culture.

Wireless LAN security management with location detection capability in hospitals.

PubMed

Tanaka, K; Atarashi, H; Yamaguchi, I; Watanabe, H; Yamamoto, R; Ohe, K

2012-01-01

In medical institutions, unauthorized access points and terminals obstruct the stable operation of a large-scale wireless local area network (LAN) system. By establishing a real-time monitoring method to detect such unauthorized wireless devices, we can improve the efficiency of security management. We detected unauthorized wireless devices by using a centralized wireless LAN system and a location detection system at 370 access points at the University of Tokyo Hospital. By storing the detected radio signal strength and location information in a database, we evaluated the risk level from the detection history. We also evaluated the location detection performance in our hospital ward using Wi-Fi tags. The presence of electric waves outside the hospital and those emitted from portable game machines with wireless communication capability was confirmed from the detection result. The location detection performance showed an error margin of approximately 4 m in detection accuracy and approximately 5% in false detection. Therefore, it was effective to consider the radio signal strength as both an index of likelihood at the detection location and an index for the level of risk. We determined the location of wireless devices with high accuracy by filtering the detection results on the basis of radio signal strength and detection history. Results of this study showed that it would be effective to use the developed location database containing radio signal strength and detection history for security management of wireless LAN systems and more general-purpose location detection applications.

Cyanobacteria and Cyanotoxins Occurrence and Removal from Five High-Risk Conventional Treatment Drinking Water Plants.

PubMed

Szlag, David C; Sinclair, James L; Southwell, Benjamin; Westrick, Judy A

2015-06-12

An environmental protection agency EPA expert workshop prioritized three cyanotoxins, microcystins, anatoxin-a, and cylindrospermopsin (MAC), as being important in freshwaters of the United States. This study evaluated the prevalence of potentially toxin producing cyanobacteria cell numbers relative to the presence and quantity of the MAC toxins in the context of this framework. Total and potential toxin producing cyanobacteria cell counts were conducted on weekly raw and finished water samples from utilities located in five US states. An Enzyme-Linked Immunosorbant Assay (ELISA) was used to screen the raw and finished water samples for microcystins. High-pressure liquid chromatography with a photodiode array detector (HPLC/PDA) verified microcystin concentrations and quantified anatoxin-a and cylindrospermopsin concentrations. Four of the five utilities experienced cyanobacterial blooms in their raw water. Raw water samples from three utilities showed detectable levels of microcystins and a fourth utility had detectable levels of both microcystin and cylindrospermopsin. No utilities had detectable concentrations of anatoxin-a. These conventional plants effectively removed the cyanobacterial cells and all finished water samples showed MAC levels below the detection limit by ELISA and HPLC/PDA.

The importance of sample collection when using single cytokine levels and systemic cytokine profiles as biomarkers--a comparative study of serum versus plasma samples.

PubMed

Tvedt, Tor Henrik Anderson; Rye, Kristin Paulsen; Reikvam, Håkon; Brenner, Annette K; Bruserud, Øystein

2015-03-01

Cytokines, soluble adhesion molecules and metalloproteinases can be detected in human serum or plasma samples. Such systemic levels are widely used as biomarkers in epidemiological and clinical studies. We prepared serum samples and three types of plasma samples (EDTA, heparin, citric acid) from 20 healthy individuals. The levels of 31 cytokines, four soluble adhesion molecules and eight matrix metalloproteinases were analyzed by Luminex technology. Most mediators showed detectable levels in both plasma and serum. Several mediators that can be released by platelets showed increased serum levels, especially CCL5 and CD40L, but for the other mediators the serum levels did not correlate with peripheral blood platelet counts and for these last mediators serum and plasma levels often showed strong correlations. The use of bivalirudin for anticoagulation significantly increased and citric acid combined with platelet inhibitors (ticagrelor, acetylsalicylic acid plus prostaglandin E2) did not alter plasma levels of platelet-store mediators compared with citric acid alone. The impact of sample preparation differed between mediators; for many mediators strong correlations were seen between serum and plasma levels even when absolute levels differed. Soluble adhesion molecule levels showed only minor differences between samples. Unsupervised hierarchical clustering suggested that the effect of sampling/preparation was strongest for serum and heparin plasma samples. Careful standardization of sample preparation is usually necessary when analyzing systemic mediator levels, and differences caused by sample preparation should be considered as a possible explanation if studies show conflicting results. Copyright © 2015 Elsevier B.V. All rights reserved.

Bio-barcode gel assay for microRNA

NASA Astrophysics Data System (ADS)

Lee, Hyojin; Park, Jeong-Eun; Nam, Jwa-Min

2014-02-01

MicroRNA has been identified as a potential biomarker because expression level of microRNA is correlated with various cancers. Its detection at low concentrations would be highly beneficial for cancer diagnosis. Here, we develop a new type of a DNA-modified gold nanoparticle-based bio-barcode assay that uses a conventional gel electrophoresis platform and potassium cyanide chemistry and show this assay can detect microRNA at aM levels without enzymatic amplification. It is also shown that single-base-mismatched microRNA can be differentiated from perfectly matched microRNA and the multiplexed detection of various combinations of microRNA sequences is possible with this approach. Finally, differently expressed microRNA levels are selectively detected from cancer cells using the bio-barcode gel assay, and the results are compared with conventional polymerase chain reaction-based results. The method and results shown herein pave the way for practical use of a conventional gel electrophoresis for detecting biomolecules of interest even at aM level without polymerase chain reaction amplification.

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.

The determination of sulfite levels and its oxidation in plant leaves.

PubMed

Brychkova, Galina; Yarmolinsky, Dmitry; Fluhr, Robert; Sagi, Moshe

2012-07-01

Sulfur is the sixth most abundant element in life and an important building block of proteins and cellular metabolites. Plants like bacteria can synthesize their sulfur-containing biomolecules from sulfate, where sulfite is an intermediate of the sulfur assimilation pathway. Above a certain threshold SO(2)/sulfite is cytotoxic and is rapidly metabolized to avoid damage. However, the existing data show considerable differences in basal sulfite levels both between species and apparent discrepancies in measured levels in the same species. In order to resolve this question we employed a sulfite detection method using chicken sulfite oxidase and developed an independent enzymatic assay, based on the specific detection of sulfite by sulfite reductase and compared those measurements to a modified colorimetric fuchsin-based method, specific for sulfite detection. We show here that when properly used the sulfite levels detected by the three methods can yield identical results. Furthermore, to examine the capacity of the plant to detoxify sulfite we injected sub-lethal sulfite solutions (yet, several folds higher than the basal levels) into Arabidopsis and tomato leaves and monitored the excess sulfite turnover. Within 3h of sulfite injection, more than 80% of the injected sulfite in Arabidopsis and 91% in tomato were oxidized to sulfate, demonstrating the high capacity of the sulfite oxidation mechanism/s in plants. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Fast Human Detection for Intelligent Monitoring Using Surveillance Visible Sensors

PubMed Central

Ko, Byoung Chul; Jeong, Mira; Nam, JaeYeal

2014-01-01

Human detection using visible surveillance sensors is an important and challenging work for intruder detection and safety management. The biggest barrier of real-time human detection is the computational time required for dense image scaling and scanning windows extracted from an entire image. This paper proposes fast human detection by selecting optimal levels of image scale using each level's adaptive region-of-interest (ROI). To estimate the image-scaling level, we generate a Hough windows map (HWM) and select a few optimal image scales based on the strength of the HWM and the divide-and-conquer algorithm. Furthermore, adaptive ROIs are arranged per image scale to provide a different search area. We employ a cascade random forests classifier to separate candidate windows into human and nonhuman classes. The proposed algorithm has been successfully applied to real-world surveillance video sequences, and its detection accuracy and computational speed show a better performance than those of other related methods. PMID:25393782

Contamination of different portions of raw and boiled specimens of Norway lobster by mercury and selenium.

PubMed

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Abete, Maria Cesarina; Gavinelli, Stefania; Amorena, Michele

2013-11-01

The aim of this study was to evaluate mercury and selenium distribution in different portions (exoskeleton, white meat and brown meat) of Norway lobster (Nephrops norvegicus). Some samples were also analysed as whole specimens. The same portions were also examined after boiling, in order to observe if this cooking practice could affect mercury and selenium concentrations. The highest mercury concentrations were detected in white meat, exceeding in all cases the maximum levels established by European legislation. The brown meat reported the highest selenium concentrations. In all boiled samples, mercury levels showed a statistically significant increase compared to raw portions. On the contrary, selenium concentrations detected in boiled samples of white meat, brown meat and whole specimen showed a statistically significant decrease compared to the corresponding raw samples. These results indicate that boiling modifies mercury and selenium concentrations. The high mercury levels detected represent a possible risk for consumers, and the publication and diffusion of specific advisories concerning seafood consumption is recommended.

Improvements in Night-Time Low Cloud Detection and MODIS-Style Cloud Optical Properties from MSG SEVIRI

NASA Technical Reports Server (NTRS)

Wind, Galina (Gala); Platnick, Steven; Riedi, Jerome

2011-01-01

The MODIS cloud optical properties algorithm (MOD06IMYD06 for Terra and Aqua MODIS, respectively) slated for production in Data Collection 6 has been adapted to execute using available channels on MSG SEVIRI. Available MODIS-style retrievals include IR Window-derived cloud top properties, using the new Collection 6 cloud top properties algorithm, cloud optical thickness from VISINIR bands, cloud effective radius from 1.6 and 3.7Jlm and cloud ice/water path. We also provide pixel-level uncertainty estimate for successful retrievals. It was found that at nighttime the SEVIRI cloud mask tends to report unnaturally low cloud fraction for marine stratocumulus clouds. A correction algorithm that improves detection of such clouds has been developed. We will discuss the improvements to nighttime low cloud detection for SEVIRI and show examples and comparisons with MODIS and CALIPSO. We will also show examples of MODIS-style pixel-level (Level-2) cloud retrievals for SEVIRI with comparisons to MODIS.

Natural occurrence of fumonisins in corn from Iran.

PubMed

Shephard, G S; Marasas, W F; Leggott, N L; Yazdanpanah, H; Rahimian, H; Safavi, N

2000-05-01

Corn collected in the Mazandaran and Isfahan Provinces of Iran was analyzed for fumonisin B(1) (FB(1)), fumonisin B(2) (FB(2)), and fumonisin B(3) (FB(3)). The samples from Mazandaran Province, situated on the Caspian littoral of Iran, were random samples from farmers' corn lots collected in September 1998, whereas those from Isfahan Province, situated further south in the center of Iran, were bought as corn cobs in the local retail market during October 1998. All 11 samples from Mazandaran showed high levels of fumonisin contamination with FB(1) levels between 1.270 and 3.980 microg/g, FB(2) levels between 0.190 and 1.175 microg/g, and FB(3) levels between 0.155 and 0.960 microg/g. Samples from Isfahan showed lower levels of contamination with eight of eight samples having detectable FB(1) (0.010-0.590 microg/g), two of eight samples having detectable FB(2) (0.050-0.075 microg/g), and two of eight samples having detectable FB(3) (0.050-0.075 microg/g). This is the first report of fumonisin contamination of corn from Iran, in which samples from the area of high esophageal cancer on the Caspian littoral have been shown to contain high levels of fumonisins.

Balancing Detection and Eradication for Control of Epidemics: Sudden Oak Death in Mixed-Species Stands

PubMed Central

Ndeffo Mbah, Martial L.; Gilligan, Christopher A.

2010-01-01

Culling of infected individuals is a widely used measure for the control of several plant and animal pathogens but culling first requires detection of often cryptically-infected hosts. In this paper, we address the problem of how to allocate resources between detection and culling when the budget for disease management is limited. The results are generic but we motivate the problem for the control of a botanical epidemic in a natural ecosystem: sudden oak death in mixed evergreen forests in coastal California, in which species composition is generally dominated by a spreader species (bay laurel) and a second host species (coast live oak) that is an epidemiological dead-end in that it does not transmit infection but which is frequently a target for preservation. Using a combination of an epidemiological model for two host species with a common pathogen together with optimal control theory we address the problem of how to balance the allocation of resources for detection and epidemic control in order to preserve both host species in the ecosystem. Contrary to simple expectations our results show that an intermediate level of detection is optimal. Low levels of detection, characteristic of low effort expended on searching and detection of diseased trees, and high detection levels, exemplified by the deployment of large amounts of resources to identify diseased trees, fail to bring the epidemic under control. Importantly, we show that a slight change in the balance between the resources allocated to detection and those allocated to control may lead to drastic inefficiencies in control strategies. The results hold when quarantine is introduced to reduce the ingress of infected material into the region of interest. PMID:20856850

Cyanobacteria and Cyanotoxins Occurrence and Removal from Five High-Risk Conventional Treatment Drinking Water Plants

PubMed Central

Szlag, David C.; Sinclair, James L.; Southwell, Benjamin; Westrick, Judy A.

2015-01-01

An environmental protection agency EPA expert workshop prioritized three cyanotoxins, microcystins, anatoxin-a, and cylindrospermopsin (MAC), as being important in freshwaters of the United States. This study evaluated the prevalence of potentially toxin producing cyanobacteria cell numbers relative to the presence and quantity of the MAC toxins in the context of this framework. Total and potential toxin producing cyanobacteria cell counts were conducted on weekly raw and finished water samples from utilities located in five US states. An Enzyme-Linked Immunosorbant Assay (ELISA) was used to screen the raw and finished water samples for microcystins. High-pressure liquid chromatography with a photodiode array detector (HPLC/PDA) verified microcystin concentrations and quantified anatoxin-a and cylindrospermopsin concentrations. Four of the five utilities experienced cyanobacterial blooms in their raw water. Raw water samples from three utilities showed detectable levels of microcystins and a fourth utility had detectable levels of both microcystin and cylindrospermopsin. No utilities had detectable concentrations of anatoxin-a. These conventional plants effectively removed the cyanobacterial cells and all finished water samples showed MAC levels below the detection limit by ELISA and HPLC/PDA. PMID:26075379

Chemical sensing thresholds for mine detection dogs

NASA Astrophysics Data System (ADS)

Phelan, James M.; Barnett, James L.

2002-08-01

Mine detection dogs have been found to be an effective method to locate buried landmines. The capabilities of the canine olfaction method are from a complex combination of training and inherent capacity of the dog for odor detection. The purpose of this effort was to explore the detection thresholds of a limited group of dogs that were trained specifically for landmine detection. Soils were contaminated with TNT and 2,4-DNT to develop chemical vapor standards to present to the dogs. Soils contained ultra trace levels of TNT and DNT, which produce extremely low vapor levels. Three groups of dogs were presented the headspace vapors from the contaminated soils in work environments for each dog group. One positive sample was placed among several that contained clean soils and, the location and vapor source (strength, type) was frequently changed. The detection thresholds for the dogs were determined from measured and extrapolated dilution of soil chemical residues and, estimated soil vapor values using phase partitioning relationships. The results showed significant variances in dog sensing thresholds, where some dogs could sense the lowest levels and others had trouble with even the highest source. The remarkable ultra-trace levels detectable by the dogs are consistent with the ultra-trace chemical residues derived from buried landmines; however, poor performance may go unnoticed without periodic challenge tests at levels consistent with performance requirements.

Environment applications for ion mobility spectrometry

NASA Technical Reports Server (NTRS)

Ritchie, Robert K.; Rudolph, Andreas

1995-01-01

The detection of environmentally important polychlorinated aromatics by ion mobility spectrometry (IMS) was investigated. Single polychlorinated biphenyl (PCB) isomers (congeners) having five or more chlorine atoms were reliably detected in isooctane solution at levels of 35 ng with a Barringer IONSCAN ion mobility spectrometer operating in negative mode; limits of detection (LOD) were extrapolated to be in the low ng region. Mixtures of up to four PCB congeners, showing characteristic multiple peaks, and complex commercial mixtures of PCBs (Aroclors) were also detected. Detection of Aroclors in transformer oil was suppressed by the presence of the antioxidant BHT (2,6-di-t-butyl4-methylphenol) in the oil. The wood preservative pentachlorophenol (PCP) was easily detected in recycled wood shavings at levels of 52 ppm with the IONSCAN; the LOD was extrapolated to be in the low ppm region.

Sensitivity of the terrestrial planet finder

NASA Technical Reports Server (NTRS)

Beichman, Charles

1998-01-01

A key long-term goal of NASA's Origins program is the detection and characterization of habitable planets orbiting stars within the solar neighborhood. A cold, space-borne interferometer operating in the mid-infrared with a approx. 75 m baseline can null the light of a parent star and detect the million-times fainter radiation from an Earth-like planet located in the "habitable zone" around stars as far as 15 pc away. Such an interferometer, designated the Terrestrial Planet Finder (TPF) by NASA, could even detect atmospheric signatures of species such as CO2, O3, and H2O indicative of either the possibility or presence of primitive life. This talk highlights some of the sensitivity issues affecting the detectability of terrestrial planets. Sensitivity calculations show that a system consisting of 2 m apertures operating at 5 AU or 4 m apertures operating at 1 AU can detect terrestrial planets in reasonable integration times for levels of exo-zodiacal emission up to 10 times that seen in our solar system (hereafter denoted as 10xSS). Additionally, simulations show that confusion noise from structures in the exo-zodiacal cloud should not impede planet detection until the exo-zodiacal emission reaches the 10xSS level.

Morphological operators for enhanced polarimetric image target detection

NASA Astrophysics Data System (ADS)

Romano, João. M.; Rosario, Dalton S.

2015-09-01

We introduce an algorithm based on morphological filters with the Stokes parameters that augments the daytime and nighttime detection of weak-signal manmade objects immersed in a predominant natural background scene. The approach features a tailored sequence of signal-enhancing filters, consisting of core morphological operators (dilation, erosion) and higher level morphological operations (e.g., spatial gradient, opening, closing) to achieve a desired overarching goal. Using representative data from the SPICE database, the results show that the approach was able to automatically and persistently detect with a high confidence level the presence of three mobile military howitzer surrogates (targets) in natural clutter.

Validation of antibiotic residue tests for dairy goats.

PubMed

Zeng, S S; Hart, S; Escobar, E N; Tesfai, K

1998-03-01

The SNAP test, LacTek test (B-L and CEF), Charm Bacillus sterothermophilus var. calidolactis disk assay (BsDA), and Charm II Tablet Beta-lactam sequential test were validated using antibiotic-fortified and -incurred goat milk following the protocol for test kit validations of the U.S. Food and Drug Administration Center for Veterinary Medicine. SNAP, Charm BsDA, and Charm II Tablet Sequential tests were sensitive and reliable in detecting antibiotic residues in goat milk. All three assays showed greater than 90% sensitivity and specificity at tolerance and detection levels. However, caution should be taken in interpreting test results at detection levels. Because of the high sensitivity of these three tests, false-violative results could be obtained in goat milk containing antibiotic residues below the tolerance level. Goat milk testing positive by these tests must be confirmed using a more sophisticated methodology, such as high-performance liquid chromatography, before the milk is condemned. LacTek B-L test did not detect several antibiotics, including penicillin G, in goat milk at tolerance levels. However, LacTek CEF was excellent in detecting ceftiofur residue in goat milk.

The Gap Detection Test: Can It Be Used to Diagnose Tinnitus?

PubMed

Boyen, Kris; Başkent, Deniz; van Dijk, Pim

2015-01-01

Animals with induced tinnitus showed difficulties in detecting silent gaps in sounds, suggesting that the tinnitus percept may be filling the gap. The main purpose of this study was to evaluate the applicability of this approach to detect tinnitus in human patients. The authors first hypothesized that gap detection would be impaired in patients with tinnitus, and second, that gap detection would be more impaired at frequencies close to the tinnitus frequency of the patient. Twenty-two adults with bilateral tinnitus, 20 age-matched and hearing loss-matched subjects without tinnitus, and 10 young normal-hearing subjects participated in the study. To determine the characteristics of the tinnitus, subjects matched an external sound to their perceived tinnitus in pitch and loudness. To determine the minimum detectable gap, the gap threshold, an adaptive psychoacoustic test was performed three times by each subject. In this gap detection test, four different stimuli, with various frequencies and bandwidths, were presented at three intensity levels each. Similar to previous reports of gap detection, increasing sensation level yielded shorter gap thresholds for all stimuli in all groups. Interestingly, the tinnitus group did not display elevated gap thresholds in any of the four stimuli. Moreover, visual inspection of the data revealed no relation between gap detection performance and perceived tinnitus pitch. These findings show that tinnitus in humans has no effect on the ability to detect gaps in auditory stimuli. Thus, the testing procedure in its present form is not suitable for clinical detection of tinnitus in humans.

Temporal modulation transfer functions in cochlear implantees using a method that limits overall loudness cues

PubMed Central

Fraser, Matthew; McKay, Colette M.

2012-01-01

Temporal modulation transfer functions (TMTFs) were measured for six users of cochlear implants, using different carrier rates and levels. Unlike most previous studies investigating modulation detection, the experimental design limited potential effects of overall loudness cues. Psychometric functions (percent correct discrimination of modulated from unmodulated stimuli versus modulation depth) were obtained. For each modulation depth, each modulated stimulus was loudness balanced to the unmodulated reference stimulus, and level jitter was applied in the discrimination task. The loudness-balance data showed that the modulated stimuli were louder than the unmodulated reference stimuli with the same average current, thus confirming the need to limit loudness cues when measuring modulation detection. TMTFs measured in this way had a low-pass characteristic, with a cut-off frequency (at comfortably loud levels) similar to that for normal-hearing listeners. A reduction in level caused degradation in modulation detection efficiency and a lower-cut-off frequency (i.e. poorer temporal resolution). An increase in carrier rate also led to a degradation in modulation detection efficiency, but only at lower levels or higher modulation frequencies. When detection thresholds were expressed as a proportion of dynamic range, there was no effect of carrier rate for the lowest modulation frequency (50 Hz) at either level. PMID:22146425

Optical arc sensor using energy harvesting power source

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

Choi, Kyoo Nam, E-mail: knchoi@inu.ac.kr; Rho, Hee Hyuk, E-mail: rdoubleh0902@inu.ac.kr

Wireless sensors without external power supply gained considerable attention due to convenience both in installation and operation. Optical arc detecting sensor equipping with self sustaining power supply using energy harvesting method was investigated. Continuous energy harvesting method was attempted using thermoelectric generator to supply standby power in micro ampere scale and operating power in mA scale. Peltier module with heat-sink was used for high efficiency electricity generator. Optical arc detecting sensor with hybrid filter showed insensitivity to fluorescent and incandescent lamps under simulated distribution panel condition. Signal processing using integrating function showed selective arc discharge detection capability to different arcmore » energy levels, with a resolution below 17 J energy difference, unaffected by bursting arc waveform. The sensor showed possibility for application to arc discharge detecting sensor in power distribution panel. Also experiment with proposed continuous energy harvesting method using thermoelectric power showed possibility as a self sustainable power source of remote sensor.« less

Optical arc sensor using energy harvesting power source

NASA Astrophysics Data System (ADS)

Choi, Kyoo Nam; Rho, Hee Hyuk

2016-06-01

Wireless sensors without external power supply gained considerable attention due to convenience both in installation and operation. Optical arc detecting sensor equipping with self sustaining power supply using energy harvesting method was investigated. Continuous energy harvesting method was attempted using thermoelectric generator to supply standby power in micro ampere scale and operating power in mA scale. Peltier module with heat-sink was used for high efficiency electricity generator. Optical arc detecting sensor with hybrid filter showed insensitivity to fluorescent and incandescent lamps under simulated distribution panel condition. Signal processing using integrating function showed selective arc discharge detection capability to different arc energy levels, with a resolution below 17J energy difference, unaffected by bursting arc waveform. The sensor showed possibility for application to arc discharge detecting sensor in power distribution panel. Also experiment with proposed continuous energy harvesting method using thermoelectric power showed possibility as a self sustainable power source of remote sensor.

Existence of a soluble form of CD50 (intercellular adhesion molecule-3) produced upon human lymphocyte activation. Present in normal human serum and levels are increased in the serum of systemic lupus erythematosus patients.

PubMed

Pino-Otín, M R; Viñas, O; de la Fuente, M A; Juan, M; Font, J; Torradeflot, M; Pallarés, L; Lozano, F; Alberola-Ila, J; Martorell, J

1995-03-15

CD50 (ICAM-3) is a leukocyte differentiation Ag expressed almost exclusively on hemopoietic cells, with a key role in the first steps of immune response. To develop a specific sandwich ELISA to detect a soluble CD50 form (sCD50), two different mAbs (140-11 and 101-1D2) recognizing non-overlapping epitopes were used. sCD50 was detected in the supernatant of stimulated PBMCs, with the highest levels after CD3 triggering. Simultaneously, the CD50 surface expression diminished during the first 24 h. sCD50 isolated from culture supernatant and analyzed by immunoblotting showed an apparent m.w. of 95 kDa, slightly smaller than the membrane form. These data, together with Northern blot kinetics analysis, suggest that sCD50 is cleaved from cell membrane. Furthermore, we detect sCD50 in normal human sera and higher levels in sera of systemic lupus erythematosus (SLE) patients, especially in those in active phase. The sCD50 levels showed a positive correlation with sCD27 levels (r = 0.4213; p = 0.0026). Detection of sCD50, both after in vitro CD3 triggering of PBMCs and increased in SLE sera, suggests that sCD50 could be used as a marker of lymphocyte stimulation.

New Graph Models and Algorithms for Detecting Salient Structures from Cluttered Images

DTIC Science & Technology

2010-02-24

Development of graph models and algorithms to detect boundaries that show certain levels of symmetry, an important geometric property of many...Bookstein. Morphometric tools for landmark data. Cambridge University Press, 1991. [8] F. L. Bookstein. Principal warps: Thin-plate splines and the

Automatically Detecting Likely Edits in Clinical Notes Created Using Automatic Speech Recognition

PubMed Central

Lybarger, Kevin; Ostendorf, Mari; Yetisgen, Meliha

2017-01-01

The use of automatic speech recognition (ASR) to create clinical notes has the potential to reduce costs associated with note creation for electronic medical records, but at current system accuracy levels, post-editing by practitioners is needed to ensure note quality. Aiming to reduce the time required to edit ASR transcripts, this paper investigates novel methods for automatic detection of edit regions within the transcripts, including both putative ASR errors but also regions that are targets for cleanup or rephrasing. We create detection models using logistic regression and conditional random field models, exploring a variety of text-based features that consider the structure of clinical notes and exploit the medical context. Different medical text resources are used to improve feature extraction. Experimental results on a large corpus of practitioner-edited clinical notes show that 67% of sentence-level edits and 45% of word-level edits can be detected with a false detection rate of 15%. PMID:29854187

Determination of Total Petroleum Hydrocarbons in Australian Groundwater Through the Improvised Gas Chromatography-Flame Ionization Detection Technique.

PubMed

Faustorilla, Maria Vilma; Chen, Zuliang; Dharmarajan, Rajarathnam; Naidu, Ravendra

2017-09-01

Assessment of total petroleum hydrocarbons (TPHs) from contaminated sites demands routine and reliable measurement at trace levels. However, the detection limits of these methods need to be improved. This study developed the programmable temperature vaporization-large volume injection (PTV-LVI) method to quantify TPHs through gas chromatography-flame ionization detection. This configuration enhances the method sensitivity for trace level detections through large volume injections and pre-concentration of analytes along the injection liner. The method was evaluated for the three commonly observed hydrocarbon fractions: C10-C14, C15-C28 and C29-C36. In comparison with conventional injection methods (splitless and pulsed splitless), PTV-LVI showed R2 values > 0.999 with enhanced limits of detection and limits of quantification values. The method was applied to real samples for routine environmental monitoring of TPHs in an Australian contaminated site characterized by refueling station. Analysis of groundwater samples in the area showed a wide range of TPH concentrations as follows: 66-1,546,000 (C10-C14), 216-22,762 (C15-C28) and 105-2,103 (C29-C36) μg/L. This method has detected trace levels, thereby measuring a wider concentration range of TPHs. These more accurate measurements can lead to the appropriate application of risk assessments and remediation techniques. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Radiation Levels on the Way to Mars

NASA Image and Video Library

2012-08-02

This graphic shows the flux of radiation detected by NASA Mars Science Laboratory on the trip from Earth to Mars; the spikes in radiation levels occurred because of large solar energetic particle events caused by giant flares on the sun.

Detection of phosphatidylserine-positive exosomes for the diagnosis of early-stage malignancies.

PubMed

Sharma, Raghava; Huang, Xianming; Brekken, Rolf A; Schroit, Alan J

2017-08-08

There has been increasing interest in the detection of tumour exosomes in blood for cancer diagnostics. Most studies have focussed on miRNA and protein signatures that are surrogate markers for specific tumour types. Because tumour cells and tumour-derived exosomes display phosphatidylserine (PS) in their outer membrane leaflet, we developed a highly sensitive ELISA-based system that detects picogram amounts of exosomal phospholipid in plasma as a cancer biomarker. This report describes the development of a highly specific and sensitive ELISA for the capture of PS-expressing tumour exosomes in the blood of tumour-bearing mice. To monitor the relationship between tumour burden and tumour exosome plasma concentrations, plasma from one transplantable breast cancer model (MDA-MB-231) and three genetic mouse models (MMTV-PyMT; breast and KIC and KPC; pancreatic) were screened for captured exosomal phospholipid. We show that quantitative assessment of PS-expressing tumour exosomes detected very early-stage malignancies before clinical evidence of disease in all four model systems. Tumour exosome levels showed significant increases by day 7 after tumour implantation in the MDA-MB-231 model while palpable tumours appeared only after day 27. For the MMTV-PyMT and KIC models, tumour exosome levels increased significantly by day 49 (P⩽0.0002) and day 21 (P⩽0.001) while tumours developed only after days 60 and 40, respectively. For the KPC model, a significant increase in blood exosome levels was detected by day 70 (P=0.023) when only preinvasive lesions are microscopically detectable. These data indicate that blood PS exosome levels is a specific indicator of cancer and suggest that blood PS is a biomarker for early-stage malignancies.

Liquid extraction surface analysis (LESA) of food surfaces employing chip-based nano-electrospray mass spectrometry.

PubMed

Eikel, Daniel; Henion, Jack

2011-08-30

An automated surface-sampling technique called liquid extraction surface analysis (LESA), coupled with infusion nano-electrospray high-resolution mass spectrometry and tandem mass spectrometry (MS/MS), is described and applied to the qualitative determination of surface chemical residues resulting from the artificial spraying of selected fresh fruits and vegetables with representative pesticides. Each of the targeted pesticides was readily detected with both high-resolution and full-scan collision-induced dissociation (CID) mass spectra. In the case of simazine and sevin, a mass resolution of 100,000 was insufficient to distinguish the isobaric protonated molecules for these compounds. When the surface of a spinach leaf was analyzed by LESA, trace levels of diazinon were readily detected on the spinach purchased directly from a supermarket before they were sprayed with the five-pesticide mixture. A 30 s rinse under hot running tap water appeared to quantitatively remove all remaining residues of this pesticide. Diazinon was readily detected by LESA analysis on the skin of the artificially sprayed spinach. Finally, incurred pyrimethanil at a level of 169 ppb in a batch slurry of homogenized apples was analyzed by LESA and this pesticide was readily detected by both high-resolution mass spectrometry and full-scan CID mass spectrometry, thus showing that pesticides may also be detected in whole fruit homogenized samples. This report shows that representative pesticides on fruit and vegetable surfaces present at levels 20-fold below generally allowed EPA tolerance levels are readily detected and confirmed by the title technologies making LESA-MS as interesting screening method for food safety purposes. Copyright © 2011 John Wiley & Sons, Ltd.

Computer-aided detection of initial polyp candidates with level set-based adaptive convolution

NASA Astrophysics Data System (ADS)

Zhu, Hongbin; Duan, Chaijie; Liang, Zhengrong

2009-02-01

In order to eliminate or weaken the interference between different topological structures on the colon wall, adaptive and normalized convolution methods were used to compute the first and second order spatial derivatives of computed tomographic colonography images, which is the beginning of various geometric analyses. However, the performance of such methods greatly depends on the single-layer representation of the colon wall, which is called the starting layer (SL) in the following text. In this paper, we introduce a level set-based adaptive convolution (LSAC) method to compute the spatial derivatives, in which the level set method is employed to determine a more reasonable SL. The LSAC was applied to a computer-aided detection (CAD) scheme to detect the initial polyp candidates, and experiments showed that it benefits the CAD scheme in both the detection sensitivity and specificity as compared to our previous work.

Optimizing bulk milk dioxin monitoring based on costs and effectiveness.

PubMed

Lascano-Alcoser, V H; Velthuis, A G J; van der Fels-Klerx, H J; Hoogenboom, L A P; Oude Lansink, A G J M

2013-07-01

Dioxins are environmental pollutants, potentially present in milk products, which have negative consequences for human health and for the firms and farms involved in the dairy chain. Dioxin monitoring in feed and food has been implemented to detect their presence and estimate their levels in food chains. However, the costs and effectiveness of such programs have not been evaluated. In this study, the costs and effectiveness of bulk milk dioxin monitoring in milk trucks were estimated to optimize the sampling and pooling monitoring strategies aimed at detecting at least 1 contaminated dairy farm out of 20,000 at a target dioxin concentration level. Incidents of different proportions, in terms of the number of contaminated farms, and concentrations were simulated. A combined testing strategy, consisting of screening and confirmatory methods, was assumed as well as testing of pooled samples. Two optimization models were built using linear programming. The first model aimed to minimize monitoring costs subject to a minimum required effectiveness of finding an incident, whereas the second model aimed to maximize the effectiveness for a given monitoring budget. Our results show that a high level of effectiveness is possible, but at high costs. Given specific assumptions, monitoring with 95% effectiveness to detect an incident of 1 contaminated farm at a dioxin concentration of 2 pg of toxic equivalents/g of fat [European Commission's (EC) action level] costs €2.6 million per month. At the same level of effectiveness, a 73% cost reduction is possible when aiming to detect an incident where 2 farms are contaminated at a dioxin concentration of 3 pg of toxic equivalents/g of fat (EC maximum level). With a fixed budget of €40,000 per month, the probability of detecting an incident with a single contaminated farm at a dioxin concentration equal to the EC action level is 4.4%. This probability almost doubled (8.0%) when aiming to detect the same incident but with a dioxin concentration equal to the EC maximum level. This study shows that the effectiveness of finding an incident depends not only on the ratio at which, for testing, collected truck samples are mixed into a pooled sample (aiming at detecting certain concentration), but also the number of collected truck samples. In conclusion, the optimal cost-effective monitoring depends on the number of contaminated farms and the concentration aimed at detection. The models and study results offer quantitative support to risk managers of food industries and food safety authorities. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Comparing efficacy of different taxonomic resolutions and surrogates in detecting changes in soft bottom assemblages due to coastal defence structures.

PubMed

Bertasi, Fabio; Colangelo, Marina Antonia; Colosio, Francesco; Gregorio, Gianni; Abbiati, Marco; Ceccherelli, Victor Ugo

2009-05-01

Sandy shores on the West coast of the North Adriatic Sea are extensively protected by different types of defence structures to prevent coastal erosion. Coastal defence schemes modify the hydrodynamic regime, the sediment structure and composition thus affecting the benthic assemblages. This study examines the effectiveness in detecting changes in soft bottom assemblages caused by coastal defence structures by using different levels of taxonomic resolution, polychaetes and/or bivalves as surrogates and different data transformations. A synoptic analyses of three datasets of subtidal benthic macrofauna used in studies aimed at assessing the impact of breakwaters along the North Adriatic coast has been done. Analyses of similarities and correlations between distance matrices were done using matrices with different levels of taxonomic resolution, and with polychaetes or bivalves data alone. Lentidium mediterraneum was the most abundant species in all datasets. Its abundance was not consistently related to the presence of defence structures. Moreover, distribution patterns of L. mediterraneum were masking the structure of the whole macrofaunal assemblages. Removal of L. mediterraneum from the datasets allowed the detection of changes in benthic assemblages due to coastal defences. Analyses on different levels of taxonomic resolution showed that the level of family maintained sufficient information to detect the impacts of coastal defence structures on benthic assemblages. Moreover, the outcomes depended on the transformation used. Patterns of distribution of bivalves, used as surrogates, showed low correlations with the patterns of the total macrofaunal species assemblages. Patterns of polychaetes, if identified to the species or genus level showed higher correlations with the whole dataset. However, the identification of polychaetes to species and genus level is as costly as the identification of all macrobenthic taxa at family level. This study provided additional evidences that taxonomic sufficiency is a useful tool in environmental monitoring, also in investigations on the impacts of coastal defence structures on subtidal macrofauna. The use of coarser taxonomic level, being time-efficient, would allow improving sampling designs of monitoring programs by increasing replication in space and time and by allowing long term monitoring studies.

The forest, the trees, and the leaves: Differences of processing across development.

PubMed

Krakowski, Claire-Sara; Poirel, Nicolas; Vidal, Julie; Roëll, Margot; Pineau, Arlette; Borst, Grégoire; Houdé, Olivier

2016-08-01

To act and think, children and adults are continually required to ignore irrelevant visual information to focus on task-relevant items. As real-world visual information is organized into structures, we designed a feature visual search task containing 3-level hierarchical stimuli (i.e., local shapes that constituted intermediate shapes that formed the global figure) that was presented to 112 participants aged 5, 6, 9, and 21 years old. This task allowed us to explore (a) which level is perceptively the most salient at each age (i.e., the fastest detected level) and (b) what kind of attentional processing occurs for each level across development (i.e., efficient processing: detection time does not increase with the number of stimuli on the display; less efficient processing: detection time increases linearly with the growing number of distractors). Results showed that the global level was the most salient at 5 years of age, whereas the global and intermediate levels were both salient for 9-year-olds and adults. Interestingly, at 6 years of age, the intermediate level was the most salient level. Second, all participants showed an efficient processing of both intermediate and global levels of hierarchical stimuli, and a less efficient processing of the local level, suggesting a local disadvantage rather than a global advantage in visual search. The cognitive cost for selecting the local target was higher for 5- and 6-year-old children compared to 9-year-old children and adults. These results are discussed with regards to the development of executive control. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Regional Principal Color Based Saliency Detection

PubMed Central

Lou, Jing; Ren, Mingwu; Wang, Huan

2014-01-01

Saliency detection is widely used in many visual applications like image segmentation, object recognition and classification. In this paper, we will introduce a new method to detect salient objects in natural images. The approach is based on a regional principal color contrast modal, which incorporates low-level and medium-level visual cues. The method allows a simple computation of color features and two categories of spatial relationships to a saliency map, achieving higher F-measure rates. At the same time, we present an interpolation approach to evaluate resulting curves, and analyze parameters selection. Our method enables the effective computation of arbitrary resolution images. Experimental results on a saliency database show that our approach produces high quality saliency maps and performs favorably against ten saliency detection algorithms. PMID:25379960

Detecting technology of biophotons

NASA Astrophysics Data System (ADS)

Ma, Junfu; Zhu, Zhaohui; Zhu, Yanbin

2002-03-01

A key technique of detecting the ultra-weak photon emission from biological system (UPE) is to change the light signal of an extremely weak level into electric signal of a considerable level when the photo-electric detecting system were be applied. This paper analyzed the difficult for detecting the ultra-weak photon emission from biological system (UPE) mainly is in the absence of high sensitivity detector in UV-visible-infra spectra region. An experimental setup for testing UPE in different spectral region was designed. Using the experimental setup the test data of different several spectral regions from 300 nm to 1060 nm has were tested. The test result show the UPE of living biological system exists in wide spectra region from UV- visible to infrared.

A study of the use of vibration and stress wave sensing for the detection of bearing failure

NASA Technical Reports Server (NTRS)

Ensor, L. C.; Feng, C. C.

1975-01-01

Results from an experimental study of vibrations and stress waves emitted from ball bearings are presented. Fatique tests were run with both high quality bearings and man faulted bearings, all of one size. Tests were instrumented with different sensors to detect the noises from 10 Hz to 1 MHz. Frequency spectrum plots are presented. The modulation characteristics of the ultrasonic noises were analyzed, and acoustic emission type measurements were conducted. Results are presented which show that there are usable acoustic signal levels even beyond 500 KHz. These signal levels are modulated by a low frequency carrier which is a function of the stress loading and acoustic transmissibility. The results were correlated to fault size in the bearings. The correlation shows that the sensor used for signals from 100 KHz to 1 MHz gave the best sensitivity and detected the generation of very small spalls or pits.

Advanced Augmented White Cane with obstacle height and distance feedback.

PubMed

Pyun, Rosali; Kim, Yeongmi; Wespe, Pascal; Gassert, Roger; Schneller, Stefan

2013-06-01

The white cane is a widely used mobility aid that helps visually impaired people navigate the surroundings. While it reliably and intuitively extends the detection range of ground-level obstacles and drop-offs to about 1.2 m, it lacks the ability to detect trunk and head-level obstacles. Electronic Travel Aids (ETAs) have been proposed to overcome these limitations, but have found minimal adoption due to limitations such as low information content and low reliability thereof. Although existing ETAs extend the sensing range beyond that of the conventional white cane, most of them do not detect head-level obstacles and drop-offs, nor can they identify the vertical extent of obstacles. Furthermore, some ETAs work independent of the white cane, and thus reliable detection of surface textures and drop-offs is not provided. This paper introduces a novel ETA, the Advanced Augmented White Cane, which detects obstacles at four vertical levels and provides multi-sensory feedback. We evaluated the device in five blindfolded subjects through reaction time measurements following the detection of an obstacle, as well as through the reliability of dropoff detection. The results showed that our aid could help the user successfully detect an obstacle and identify its height, with an average reaction time of 410 msec. Drop-offs were reliably detected with an intraclass correlation > 0.95. This work is a first step towards a low-cost ETA to complement the functionality of the conventional white cane.

Potential Role of Pet Cats As a Sentinel Species for Human Exposure to Flame Retardants

PubMed Central

Henríquez-Hernández, Luis A.; Carretón, Elena; Camacho, María; Montoya-Alonso, José Alberto; Boada, Luis D.; Bernal Martín, Verónica; Falcón Cordón, Yaiza; Falcón Cordón, Soraya; Zumbado, Manuel; Luzardo, Octavio P.

2017-01-01

Flame retardants are a wide group of chemicals used by the industry to avoid combustion of materials. These substances are commonly found in plastics, electronic equipment, fabrics, and in many other everyday articles. Subsequently, ubiquitous environmental contamination by these common chemical is frequently reported. In the present study, we have evaluated the level of exposure to polychlorinated biphenyls (PCBs), brominated diphenyl ethers (BDEs), and organophosphorous flame retardants (OPFRs) in pet cats through the analysis of their serum. We also analyzed the level exposure to such chemicals in a series of 20 cat owners, trying to disclose the role of pet cats as sentinel species of human exposure to FRs. Our results showed that PCBs, banned 40 years ago, showed the lowest levels of exposure, followed by BDEs—banned recently. Congeners PCB-138 and PCB-180 were detected in ≥50% of the series, while BDE-47 was detected in near 90% of the pet cats. On the other hand, the highest levels were that of OPFRs, whose pattern of detection was similar to that observed in humans, thus suggesting a potential role of cats as a sentinel species for human exposure to these currently used FRs. Six out of 11 OPFRs determined [2-ethylhexyldiphenyl phosphate, tributylphosphate, triisobutylphosphate, triphenylphosphate, tris (2-chloroethyl) phosphate, and tris (2-chloroisopropyl) phosphate] were detected in 100% of the samples. It will be interesting to perform future studied aimed to elucidating the potential toxicological effects of these highly detected chemicals both, in cats and humans. PMID:28620612

An image cytometric technique is a concise method to detect adenoviruses and host cell proteins and to monitor the infection and cellular responses induced.

PubMed

Morinaga, Takao; Nguyễn, Thảo Thi Thanh; Zhong, Boya; Hanazono, Michiko; Shingyoji, Masato; Sekine, Ikuo; Tada, Yuji; Tatsumi, Koichiro; Shimada, Hideaki; Hiroshima, Kenzo; Tagawa, Masatoshi

2017-11-10

Genetically modified adenoviruses (Ad) with preferential replications in tumor cells have been examined for a possible clinical applicability as an anti-cancer agent. A simple method to detect viral and cellular proteins is valuable to monitor the viral infections and to predict the Ad-mediated cytotoxicity. We used type 5 Ad in which the expression of E1A gene was activated by 5'-regulatory sequences of genes that were augmented in the expression in human tumors. The Ad were further modified to have the fiber-knob region replaced with that derived from type 35 Ad. We infected human mesothelioma cells with the fiber-replaced Ad, and sequentially examined cytotoxic processes together with an expression level of the viral E1A, hexon, and cellular cleaved caspase-3 with image cytometric and Western blot analyses. The replication-competent Ad produced cytotoxicity on mesothelioma cells. The infected cells expressed E1A and hexon 24 h after the infection and then showed cleavage of caspase-3, all of which were detected with image cytometry and Western blot analysis. Image cytometry furthermore demonstrated that increased Ad doses did not enhance an expression level of E1A and hexon in an individual cell and that caspase-3-cleaved cells were found more frequently in hexon-positive cells than in E1A-positive cells. Image cytometry thus detected these molecular changes in a sensitive manner and at a single cell level. We also showed that an image cytometric technique detected expression changes of other host cell proteins, cyclin-E and phosphorylated histone H3 at a single cell level. Image cytometry is a concise procedure to detect expression changes of Ad and host cell proteins at a single cell level, and is useful to analyze molecular events after the infection.

Measurement of Non-Invasive Blood Glucose Level Based Sensor Color TCS3200 and Arduino

NASA Astrophysics Data System (ADS)

Kurniadi Wardana, Humaidillah; Indahwati, Elly; Arifah Fitriyah, Lina

2018-04-01

Design and measurement of Arduino-based urinary (non-invasive) urine glucose using RGB tcs3200 sensor. This research was conducted by making use of the urine in diabetes patients detected by sensor colours then measured levels of colour based on the RGB colour of the urine of diabetics. The detection is done on 4 urine samples with each consisting of 3 diabetics and 1 non-diabetics. Equipment used in this research, among others, Arduino Uno, colour sensor tcs3200, LCD 16x4. The results showed that the detection of RGB values in diabetics 230 with blue and not diabetics 200 with red.

[Determination of homocysteine level in plasma by high performance liquids chromatography with fluorescence detection].

PubMed

Da, Xu; Qian, Ling-Jia

2005-08-01

To establish a method for detection of plasma total homocysteine with HPLC. The chromatography analysis was carried out using a Symmetry Shield RP18. The mobile phase was sodium acetate (0.08 mol/L) and methanol (1%) and we utilized a HPLC system with fluorescence detection of plasma homocysteine derivatized from reaction with 7-fluorobenzo-2-oxa-1,3-diazole-4-sulphonate (SBD-F). The average recoveries were 95.8 - 100.8% and the relative standard deviations were 1.2-2.0%. The results showed it to be a rapid and accurate method for the determination of homocysteine level in plasma.

A robust sub-pixel edge detection method of infrared image based on tremor-based retinal receptive field model

NASA Astrophysics Data System (ADS)

Gao, Kun; Yang, Hu; Chen, Xiaomei; Ni, Guoqiang

2008-03-01

Because of complex thermal objects in an infrared image, the prevalent image edge detection operators are often suitable for a certain scene and extract too wide edges sometimes. From a biological point of view, the image edge detection operators work reliably when assuming a convolution-based receptive field architecture. A DoG (Difference-of- Gaussians) model filter based on ON-center retinal ganglion cell receptive field architecture with artificial eye tremors introduced is proposed for the image contour detection. Aiming at the blurred edges of an infrared image, the subsequent orthogonal polynomial interpolation and sub-pixel level edge detection in rough edge pixel neighborhood is adopted to locate the foregoing rough edges in sub-pixel level. Numerical simulations show that this method can locate the target edge accurately and robustly.

Laser Calorimetry Spectroscopy for ppm-level Dissolved Gas Detection and Analysis

PubMed Central

K. S., Nagapriya; Sinha, Shashank; R., Prashanth; Poonacha, Samhitha; Chaudhry, Gunaranjan; Bhattacharya, Anandaroop; Choudhury, Niloy; Mahalik, Saroj; Maity, Sandip

2017-01-01

In this paper we report a newly developed technique – laser calorimetry spectroscopy (LCS), which is a combination of laser absorption spectroscopy and calorimetry - for the detection of gases dissolved in liquids. The technique involves determination of concentration of a dissolved gas by irradiating the liquid with light of a wavelength where the gas absorbs, and measuring the temperature change caused by the absorbance. Conventionally, detection of dissolved gases with sufficient sensitivity and specificity was done by first extracting the gases from the liquid and then analyzing the gases using techniques such as gas chromatography. Using LCS, we have been able to detect ppm levels of dissolved gases without extracting them from the liquid. In this paper, we show the detection of dissolved acetylene in transformer oil in the mid infrared (MIR) wavelength (3021 nm) region. PMID:28218304

Laser Calorimetry Spectroscopy for ppm-level Dissolved Gas Detection and Analysis.

PubMed

K S, Nagapriya; Sinha, Shashank; R, Prashanth; Poonacha, Samhitha; Chaudhry, Gunaranjan; Bhattacharya, Anandaroop; Choudhury, Niloy; Mahalik, Saroj; Maity, Sandip

2017-02-20

In this paper we report a newly developed technique - laser calorimetry spectroscopy (LCS), which is a combination of laser absorption spectroscopy and calorimetry - for the detection of gases dissolved in liquids. The technique involves determination of concentration of a dissolved gas by irradiating the liquid with light of a wavelength where the gas absorbs, and measuring the temperature change caused by the absorbance. Conventionally, detection of dissolved gases with sufficient sensitivity and specificity was done by first extracting the gases from the liquid and then analyzing the gases using techniques such as gas chromatography. Using LCS, we have been able to detect ppm levels of dissolved gases without extracting them from the liquid. In this paper, we show the detection of dissolved acetylene in transformer oil in the mid infrared (MIR) wavelength (3021 nm) region.

The Gap Detection Test: Can It Be Used to Diagnose Tinnitus?

PubMed Central

Boyen, Kris; Başkent, Deniz

2015-01-01

Objectives: Animals with induced tinnitus showed difficulties in detecting silent gaps in sounds, suggesting that the tinnitus percept may be filling the gap. The main purpose of this study was to evaluate the applicability of this approach to detect tinnitus in human patients. The authors first hypothesized that gap detection would be impaired in patients with tinnitus, and second, that gap detection would be more impaired at frequencies close to the tinnitus frequency of the patient. Design: Twenty-two adults with bilateral tinnitus, 20 age-matched and hearing loss–matched subjects without tinnitus, and 10 young normal-hearing subjects participated in the study. To determine the characteristics of the tinnitus, subjects matched an external sound to their perceived tinnitus in pitch and loudness. To determine the minimum detectable gap, the gap threshold, an adaptive psychoacoustic test was performed three times by each subject. In this gap detection test, four different stimuli, with various frequencies and bandwidths, were presented at three intensity levels each. Results: Similar to previous reports of gap detection, increasing sensation level yielded shorter gap thresholds for all stimuli in all groups. Interestingly, the tinnitus group did not display elevated gap thresholds in any of the four stimuli. Moreover, visual inspection of the data revealed no relation between gap detection performance and perceived tinnitus pitch. Conclusions: These findings show that tinnitus in humans has no effect on the ability to detect gaps in auditory stimuli. Thus, the testing procedure in its present form is not suitable for clinical detection of tinnitus in humans. PMID:25822647

Multi person detection and tracking based on hierarchical level-set method

NASA Astrophysics Data System (ADS)

Khraief, Chadia; Benzarti, Faouzi; Amiri, Hamid

2018-04-01

In this paper, we propose an efficient unsupervised method for mutli-person tracking based on hierarchical level-set approach. The proposed method uses both edge and region information in order to effectively detect objects. The persons are tracked on each frame of the sequence by minimizing an energy functional that combines color, texture and shape information. These features are enrolled in covariance matrix as region descriptor. The present method is fully automated without the need to manually specify the initial contour of Level-set. It is based on combined person detection and background subtraction methods. The edge-based is employed to maintain a stable evolution, guide the segmentation towards apparent boundaries and inhibit regions fusion. The computational cost of level-set is reduced by using narrow band technique. Many experimental results are performed on challenging video sequences and show the effectiveness of the proposed method.

A comparative study of cultural methods for the detection of Salmonella in feed and feed ingredients

PubMed Central

Koyuncu, Sevinc; Haggblom, Per

2009-01-01

Background Animal feed as a source of infection to food producing animals is much debated. In order to increase our present knowledge about possible feed transmission it is important to know that the present isolation methods for Salmonella are reliable also for feed materials. In a comparative study the ability of the standard method used for isolation of Salmonella in feed in the Nordic countries, the NMKL71 method (Nordic Committee on Food Analysis) was compared to the Modified Semisolid Rappaport Vassiliadis method (MSRV) and the international standard method (EN ISO 6579:2002). Five different feed materials were investigated, namely wheat grain, soybean meal, rape seed meal, palm kernel meal, pellets of pig feed and also scrapings from a feed mill elevator. Four different levels of the Salmonella serotypes S. Typhimurium, S. Cubana and S. Yoruba were added to each feed material, respectively. For all methods pre-enrichment in Buffered Peptone Water (BPW) were carried out followed by enrichments in the different selective media and finally plating on selective agar media. Results The results obtained with all three methods showed no differences in detection levels, with an accuracy and sensitivity of 65% and 56%, respectively. However, Müller-Kauffmann tetrathionate-novobiocin broth (MKTTn), performed less well due to many false-negative results on Brilliant Green agar (BGA) plates. Compared to other feed materials palm kernel meal showed a higher detection level with all serotypes and methods tested. Conclusion The results of this study showed that the accuracy, sensitivity and specificity of the investigated cultural methods were equivalent. However, the detection levels for different feed and feed ingredients varied considerably. PMID:19192298

The IGF-I/JAK2-STAT3/miR-21 signaling pathway may be associated with human renal cell carcinoma cell growth.

PubMed

Su, Ying; Zhao, An; Cheng, Guoping; Xu, Jingjing; Ji, Enming; Sun, Wenyong

2017-07-04

Renal cell carcinoma (RCC) is the highest mortality rate of the genitourinary cancers, and the treatment options are very limited. Thus, identification of molecular mechanisms underlying RCC tumorigenesis, is critical for identifying biomarkers for RCC diagnosis and prognosis. To validate whether the IGF-I/JAK2-STAT3/miR-21 signaling pathway is associated with human RCC cell growth. qRT-PCR and Western blotting were used to detect the mRNA and protein expression levels, respectively. The MTT assay was performed to determine cell survival rate. The Annexin V-FITC/PI apoptosis detection kit was used to detect cell apoptosis. We employed RCC tissues and cell lines (A498; ACHN; Caki-1; Caki-2 and 786-O) in the study. IGF-I, and its inhibitor (NT-157) were administrated to detect the effects of IGF-I on the expression of miR-21 and p-JAK2. JAK2 inhibitor (AG490), and si-STAT3 were used to detect the effects of JAK2/STAT3 signaling pathway on the expression of miR-21. In our study, we firstly showed that the expression levels of IGF-I and miR-21 were up-regulated in RCC tissues and cell lines. After exogenous IGF-I treatment, the expression levels of miR-21, p-IGF-IR and p-JAK2 were significantly increased, whereas NT-157 treatment showed the reversed results. Further study indicated that JAK2 inhibitor or si-STAT3 significantly reversed the IGF-I-induced miR-21 expression level. Finally, we found that IGF-I treatment significantly prompted human RCC cell survival and inhibited cell apoptosis, and NT-157 treatment showed the reversed results. The IGF-I/JAK2-STAT3/miR-21 signaling pathway may be associated with human RCC cell growth.

A spatial scan statistic for nonisotropic two-level risk cluster.

PubMed

Li, Xiao-Zhou; Wang, Jin-Feng; Yang, Wei-Zhong; Li, Zhong-Jie; Lai, Sheng-Jie

2012-01-30

Spatial scan statistic methods are commonly used for geographical disease surveillance and cluster detection. The standard spatial scan statistic does not model any variability in the underlying risks of subregions belonging to a detected cluster. For a multilevel risk cluster, the isotonic spatial scan statistic could model a centralized high-risk kernel in the cluster. Because variations in disease risks are anisotropic owing to different social, economical, or transport factors, the real high-risk kernel will not necessarily take the central place in a whole cluster area. We propose a spatial scan statistic for a nonisotropic two-level risk cluster, which could be used to detect a whole cluster and a noncentralized high-risk kernel within the cluster simultaneously. The performance of the three methods was evaluated through an intensive simulation study. Our proposed nonisotropic two-level method showed better power and geographical precision with two-level risk cluster scenarios, especially for a noncentralized high-risk kernel. Our proposed method is illustrated using the hand-foot-mouth disease data in Pingdu City, Shandong, China in May 2009, compared with two other methods. In this practical study, the nonisotropic two-level method is the only way to precisely detect a high-risk area in a detected whole cluster. Copyright © 2011 John Wiley & Sons, Ltd.

Quantification of plasma myo-inositol using gas chromatography-mass spectrometry.

PubMed

Guo, Jin; Shi, Yingfei; Xu, Chengbao; Zhong, Rugang; Zhang, Feng; Zhang, Ting; Niu, Bo; Wang, Jianhua

2016-09-01

Myo-inositol (MI) deficiency is associated with an increased risk for neural tube defects (NTDs), mental disorders and metabolic diseases. We developed a gas chromatography-mass spectrometry (GC-MS) method to detect MI in human plasma, which was accurate, relatively efficient and convenient for clinical application. An external standard method was used for determination of plasma MI. Samples were analyzed by GC-MS after derivatization. The stable-isotope labeled internal standard approach was used to validate the method's accuracy. Alpha fetal protein (AFP) was detected by chemiluminescence immunoassay. The method was validated by determining the linearity, sensitivity and recovery rate. There was a good agreement between the internal standard approach and the present method. The NTD-affected pregnancies showed lower plasma MI (P=0.024) and higher AFP levels (P=0.001) than control. Maternal MI level showed a better discrimination in spina bifida subgroup, while AFP level showed a better discrimination in anencephaly subgroup after stratification analysis. We developed a sensitive and reliable method for the detection of clinical plasma MI, which might be a marker for NTDs screening, and established fundamental knowledge for clinical diagnosis and prevention for the diseases related to disturbed MI metabolism. Copyright © 2016 Elsevier B.V. All rights reserved.

Lock-in detection for pulsed electrically detected magnetic resonance

NASA Astrophysics Data System (ADS)

Hoehne, Felix; Dreher, Lukas; Behrends, Jan; Fehr, Matthias; Huebl, Hans; Lips, Klaus; Schnegg, Alexander; Suckert, Max; Stutzmann, Martin; Brandt, Martin S.

2012-04-01

We show that in pulsed electrically detected magnetic resonance (pEDMR) signal modulation in combination with a lock-in detection scheme can reduce the low-frequency noise level by one order of magnitude and in addition removes the microwave-induced non-resonant background. This is exemplarily demonstrated for spin-echo measurements in phosphorus-doped silicon. The modulation of the signal is achieved by cycling the phase of the projection pulse used in pEDMR for the readout of the spin state.

Fermilab | Tritium at Fermilab | Ferry Creek Results

Science.gov Websites

newsletter Ferry Creek Results chart This chart (click chart for larger version) shows the levels of tritium following the detection of low levels of tritium in Indian Creek in November 2005. The levels of tritium in . Fermilab continues to monitor the ponds and creeks on its site and take steps to keep the levels of tritium

Associations of Leaf Spectra with Genetic and Phylogenetic Variation in Oaks: Prospects for Remote Detection of Biodiversity

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

Cavender-Bares, Jeannine; Meireles, Jose; Couture, John

Species and phylogenetic lineages have evolved to differ in the way that they acquire and deploy resources, with consequences for their physiological, chemical and structural attributes, many of which can be detected using spectral reflectance form leaves. Recent technological advances for assessing optical properties of plants offer opportunities to detect functional traits of organisms and differentiate levels of biological organization across the tree of life. We connect leaf-level full range spectral data (400–2400 nm) of leaves to the hierarchical organization of plant diversity within the oak genus (Quercus) using field and greenhouse experiments in which environmental factors and plant agemore » are controlled. We show that spectral data significantly differentiate populations within a species and that spectral similarity is significantly associated with phylogenetic similarity among species. Furthermore, we show that hyperspectral information allows more accurate classification of taxa than spectrally-derived traits, which by definition are of lower dimensionality. Finally, model accuracy increases at higher levels in the hierarchical organization of plant diversity, such that we are able to better distinguish clades than species or populations. This pattern supports an evolutionary explanation for the degree of optical differentiation among plants and demonstrates potential for remote detection of genetic and phylogenetic diversity.« less

Associations of Leaf Spectra with Genetic and Phylogenetic Variation in Oaks: Prospects for Remote Detection of Biodiversity

DOE PAGES

Cavender-Bares, Jeannine; Meireles, Jose; Couture, John; ...

2016-03-09

Species and phylogenetic lineages have evolved to differ in the way that they acquire and deploy resources, with consequences for their physiological, chemical and structural attributes, many of which can be detected using spectral reflectance form leaves. Recent technological advances for assessing optical properties of plants offer opportunities to detect functional traits of organisms and differentiate levels of biological organization across the tree of life. We connect leaf-level full range spectral data (400–2400 nm) of leaves to the hierarchical organization of plant diversity within the oak genus (Quercus) using field and greenhouse experiments in which environmental factors and plant agemore » are controlled. We show that spectral data significantly differentiate populations within a species and that spectral similarity is significantly associated with phylogenetic similarity among species. Furthermore, we show that hyperspectral information allows more accurate classification of taxa than spectrally-derived traits, which by definition are of lower dimensionality. Finally, model accuracy increases at higher levels in the hierarchical organization of plant diversity, such that we are able to better distinguish clades than species or populations. This pattern supports an evolutionary explanation for the degree of optical differentiation among plants and demonstrates potential for remote detection of genetic and phylogenetic diversity.« less

Ultrahigh-Sensitivity Piezoresistive Pressure Sensors for Detection of Tiny Pressure.

PubMed

Li, Hongwei; Wu, Kunjie; Xu, Zeyang; Wang, Zhongwu; Meng, Yancheng; Li, Liqiang

2018-06-20

High-sensitivity pressure sensors are crucial for the ultrasensitive touch technology and E-skin, especially at the tiny-pressure range below 100 Pa. However, it is highly challenging to substantially promote sensitivity beyond the current level at several to 200 kPa -1 and to improve the detection limit lower than 0.1 Pa, which is significant for the development of pressure sensors toward ultrasensitive and highly precise detection. Here, we develop an efficient strategy to greatly improve the sensitivity near to 2000 kPa -1 using short-channel coplanar device structure and sharp microstructure, which is systematically proposed for the first time and rationalized by the mathematic calculation and analysis. Significantly, benefiting from the ultrahigh sensitivity, the detection limit is improved to be as small as 0.075 Pa. The sensitivity and detection limit are both superior to the current levels and far surpass the function of human skin. Furthermore, the sensor shows fast response time (50 μs), excellent reproducibility and stability, and low power consumption. Remarkably, the sensor shows excellent detection capacity in the tiny-pressure range, including light-emitting diode switching with a pressure of 7 Pa, ringtone (2-20 Pa) recognition, and ultrasensitive (0.1 Pa) electronic glove. This work represents a performance and strategic progress in the field of pressure sensing.

Screening test for direct oral anticoagulants with the dilute Russell viper venom time.

PubMed

Pratt, Jackie; Crispin, Philip

2018-06-01

To evaluate the dilute Russell viper venom time (DRVVT) for the detection of direct-acting oral anticoagulants (DOACs) and to investigate the effect of DOACS on coagulation assays. Patients with DOACs and controls had plasma levels determined by an anti-Xa assay and dilute thrombin clotting time (TCT). Levels were correlated with the DRVVT as well as TCT, prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, protein C, protein S and antithrombin levels. The utility of the DRVVT for detecting clinically significant levels of DOACs was evaluated. There were 44 samples from patients taking dabigatran, 83 with rivaroxaban, 18 with apixaban and 55 controls. The PT and APTT failed to detect clinically significant doses of anticoagulants adequately. The TCT was increased in patients taking dabigatran and normal in controls and patients on FXa inhibitors. There was a linear correlation with all DOAC levels and the DRVVT, with moderate precision, but it showed high sensitivity (95%) and specificity (90%) for clinically significant DOAC levels. The DRVVT detects clinically significant levels of DOACs and, in conjunction with the TCT, may be used as a screen for the presence and type of DOAC. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Clinical, pathological, and neuroimaging analyses of two cases of Leigh syndrome in a Chinese family.

PubMed

Jin, Taoran; Shen, Hongrui; Zhao, Zhe; Hu, Jing

2014-11-01

In this study, the authors examined the clinical manifestations, skeletal muscle pathological characteristics, and neuroimaging results of 2 cases of Leigh syndrome in a Chinese family. The 2 patients presented with general weakness, and 1 of them presented with an impairment of vision. Skeletal muscle biopsies showed a deficiency in cytochrome c oxidase levels. Brain magnetic resonance imaging showed increased T1 and T2 signal intensities in the centrum ovale and dentate nucleus. Diffusion-weighted imaging showed a high-intensity signal. Magnetic resonance spectroscopy showed elevated levels of lactic acid in lesions. The examination of 1 patient at disease onset and during disease remission showed that the lesions detected by magnetic resonance imaging and diffusion-weighted imaging, and the peak for lactic acid detected by magnetic resonance spectroscopy, decreased during remission. These data suggest that changes in the imaging results of patients with Leigh syndrome correlate with disease course and pathogenetic condition. © The Author(s) 2014.

Comparison of digital color fundus imaging and fluorescein angiographic findings for the early detection of diabetic retinopathy in young type 1 diabetic patients.

PubMed

Kapsala, Z; Anastasakis, A; Mamoulakis, D; Maniadaki, I; Tsilimbaris, M

2018-01-01

To compare the findings from digital 7-field color fundus (CF) photography and fundus fluorescein angiography (FFA) in young patients with diabetes mellitus (DM) type 1 without known diabetic retinopathy. In this prospective, observational cohort study, 54 type 1 diabetic patients were recruited. Participants had been diagnosed with diabetes mellitus (DM) for at least 6 years, had Best Corrected Visual Acuity of 20/25 or better and did not have any known retinal pathology. One hundred and seven eyes were analyzed. All patients underwent a complete ophthalmic examination in the Retina Service of a University Eye Clinic including digital CF imaging and FFA. The mean age of the patients was 18.6 years. Mean duration of DM was 11.3 years, and mean haemoglobin A1c (HbA1c) level was 8.6%. Of the 107 eyes, 8 eyes (7.5%) showed microvascular abnormalities on CF images, while FFA images revealed changes in 26 eyes (24.3%). Hence, 18 of the 26 eyes showing abnormalities on FFA did not show any abnormalities on CF images. Mean DM duration in the patient group with detectable microvascular changes was found to be significantly higher compared to patients without changes, while no difference in HbA1c levels, serum lipid levels or blood pressure was observed. Comparison of digital CF and FFA findings for the detection of diabetic microvascular changes in type 1 diabetic patients showed that FFA reveals more information about retinal vascular pathology for early detection of diabetic retinopathy. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Occurrence, seasonal variation and risk assessment of antibiotics in the reservoirs in North China.

PubMed

Li, Nan; Zhang, Xinbo; Wu, Wei; Zhao, Xinhua

2014-09-01

The occurrence and seasonal variability of five groups (tetracycline, quinolone, chloramphenicol, macrolide and sulfonamide) of antibiotics were investigated in the surface water of four reservoirs. The dissolved concentrations of 29 antibiotics were in the ngL(-1) level. Trace levels of all target antibiotics were analyzed using solid-phase extraction followed by liquid chromatography electrospray tandem mass spectrometry. All of the antibiotics were detected at all sampling sites, indicating widespread occurrence of antibiotics in the study area. The detection of florfenicol, josamycin, kitasamycin, spiramycin and sulfameter is the first report of these compounds in reservoir samples. The results showed an association between the presence of some antibiotics at Panjiakou reservoir and cage culture of fish. Twenty-three types of antibiotics showed significant seasonal variations (p<0.001) due to human activities and flow conditions. A risk assessment showed that all antibiotics detected could cause very low risk to algae, daphnid and fish. Further health risk need to be investigated because these reservoirs are drinking water sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

Limited copy number - high resolution melting (LCN-HRM) enables the detection and identification by sequencing of low level mutations in cancer biopsies

PubMed Central

Do, Hongdo; Dobrovic, Alexander

2009-01-01

Background Mutation detection in clinical tumour samples is challenging when the proportion of tumour cells, and thus mutant alleles, is low. The limited sensitivity of conventional sequencing necessitates the adoption of more sensitive approaches. High resolution melting (HRM) is more sensitive than sequencing but identification of the mutation is desirable, particularly when it is important to discriminate false positives due to PCR errors or template degradation from true mutations. We thus developed limited copy number - high resolution melting (LCN-HRM) which applies limiting dilution to HRM. Multiple replicate reactions with a limited number of target sequences per reaction allow low level mutations to be detected. The dilutions used (based on Ct values) are chosen such that mutations, if present, can be detected by the direct sequencing of amplicons with aberrant melting patterns. Results Using cell lines heterozygous for mutations, we found that the mutations were not readily detected when they comprised 10% of total alleles (20% tumour cells) by sequencing, whereas they were readily detectable at 5% total alleles by standard HRM. LCN-HRM allowed these mutations to be identified by direct sequencing of those positive reactions. LCN-HRM was then used to review formalin-fixed paraffin-embedded (FFPE) clinical samples showing discordant findings between sequencing and HRM for KRAS exon 2 and EGFR exons 19 and 21. Both true mutations present at low levels and sequence changes due to artefacts were detected by LCN-HRM. The use of high fidelity polymerases showed that the majority of the artefacts were derived from the damaged template rather than replication errors during amplification. Conclusion LCN-HRM bridges the sensitivity gap between HRM and sequencing and is effective in distinguishing between artefacts and true mutations. PMID:19811662

Limited copy number-high resolution melting (LCN-HRM) enables the detection and identification by sequencing of low level mutations in cancer biopsies.

PubMed

Do, Hongdo; Dobrovic, Alexander

2009-10-08

Mutation detection in clinical tumour samples is challenging when the proportion of tumour cells, and thus mutant alleles, is low. The limited sensitivity of conventional sequencing necessitates the adoption of more sensitive approaches. High resolution melting (HRM) is more sensitive than sequencing but identification of the mutation is desirable, particularly when it is important to discriminate false positives due to PCR errors or template degradation from true mutations.We thus developed limited copy number - high resolution melting (LCN-HRM) which applies limiting dilution to HRM. Multiple replicate reactions with a limited number of target sequences per reaction allow low level mutations to be detected. The dilutions used (based on Ct values) are chosen such that mutations, if present, can be detected by the direct sequencing of amplicons with aberrant melting patterns. Using cell lines heterozygous for mutations, we found that the mutations were not readily detected when they comprised 10% of total alleles (20% tumour cells) by sequencing, whereas they were readily detectable at 5% total alleles by standard HRM. LCN-HRM allowed these mutations to be identified by direct sequencing of those positive reactions.LCN-HRM was then used to review formalin-fixed paraffin-embedded (FFPE) clinical samples showing discordant findings between sequencing and HRM for KRAS exon 2 and EGFR exons 19 and 21. Both true mutations present at low levels and sequence changes due to artefacts were detected by LCN-HRM. The use of high fidelity polymerases showed that the majority of the artefacts were derived from the damaged template rather than replication errors during amplification. LCN-HRM bridges the sensitivity gap between HRM and sequencing and is effective in distinguishing between artefacts and true mutations.

Fault detection in reciprocating compressor valves under varying load conditions

NASA Astrophysics Data System (ADS)

Pichler, Kurt; Lughofer, Edwin; Pichler, Markus; Buchegger, Thomas; Klement, Erich Peter; Huschenbett, Matthias

2016-03-01

This paper presents a novel approach for detecting cracked or broken reciprocating compressor valves under varying load conditions. The main idea is that the time frequency representation of vibration measurement data will show typical patterns depending on the fault state. The problem is to detect these patterns reliably. For the detection task, we make a detour via the two dimensional autocorrelation. The autocorrelation emphasizes the patterns and reduces noise effects. This makes it easier to define appropriate features. After feature extraction, classification is done using logistic regression and support vector machines. The method's performance is validated by analyzing real world measurement data. The results will show a very high detection accuracy while keeping the false alarm rates at a very low level for different compressor loads, thus achieving a load-independent method. The proposed approach is, to our best knowledge, the first automated method for reciprocating compressor valve fault detection that can handle varying load conditions.

Electrical detection of single viruses

NASA Astrophysics Data System (ADS)

Patolsky, Fernando; Zheng, Gengfeng; Hayden, Oliver; Lakadamyali, Melike; Zhuang, Xiaowei; Lieber, Charles M.

2004-09-01

We report direct, real-time electrical detection of single virus particles with high selectivity by using nanowire field effect transistors. Measurements made with nanowire arrays modified with antibodies for influenza A showed discrete conductance changes characteristic of binding and unbinding in the presence of influenza A but not paramyxovirus or adenovirus. Simultaneous electrical and optical measurements using fluorescently labeled influenza A were used to demonstrate conclusively that the conductance changes correspond to binding/unbinding of single viruses at the surface of nanowire devices. pH-dependent studies further show that the detection mechanism is caused by a field effect, and that the nanowire devices can be used to determine rapidly isoelectric points and variations in receptor-virus binding kinetics for different conditions. Lastly, studies of nanowire devices modified with antibodies specific for either influenza or adenovirus show that multiple viruses can be selectively detected in parallel. The possibility of large-scale integration of these nanowire devices suggests potential for simultaneous detection of a large number of distinct viral threats at the single virus level.

Effect of storage, processing and cooking on glucosinolate content of Brassica vegetables.

PubMed

Song, Lijiang; Thornalley, Paul J

2007-02-01

Epidemiological studies have shown that consumption of Brassica vegetables decrease the risk of cancer. These associations are linked to dietary intake of glucosinolates and their metabolism to cancer preventive isothiocyanates. Bioavailability of glucosinolates and related isothiocyanates are influenced by storage and culinary processing of Brassica vegetables. In this work, the content of the 7 major glucosinolates in broccoli, Brussels sprouts, cauliflower and green cabbage and their stability under different storage and cooking conditions is examined. Glucosinolates and isothiocyanates were quantified by liquid chromatography with tandem mass spectrometric detection (LC-MS/MS). Isothiocyanates were detected with high sensitivity as the corresponding thiourea derivatives. Storage at ambient temperature and in a domestic refrigerator showed no significant difference and a minor loss (9-26%) of glucosinolate levels over 7 days. Vegetables shredded finely showed a marked decline of glucosinolate level with post-shredding dwell time - up to 75% over 6h. Glucosinolate losses were detected partly as isothiocyanates. Cooking by steaming, microwaving and stir-fry did not produce significant loss of glucosinolates whereas boiling showed significant losses by leaching into cooking water. Most of the loss of the glucosinolates (approximately 90%) was detected in the cooking water. Increased bioavailability of dietary isothiocyanates may be achieved by avoiding boiling of vegetables.

Detection of Cardiovascular Disease Risk's Level for Adults Using Naive Bayes Classifier.

PubMed

Miranda, Eka; Irwansyah, Edy; Amelga, Alowisius Y; Maribondang, Marco M; Salim, Mulyadi

2016-07-01

The number of deaths caused by cardiovascular disease and stroke is predicted to reach 23.3 million in 2030. As a contribution to support prevention of this phenomenon, this paper proposes a mining model using a naïve Bayes classifier that could detect cardiovascular disease and identify its risk level for adults. The process of designing the method began by identifying the knowledge related to the cardiovascular disease profile and the level of cardiovascular disease risk factors for adults based on the medical record, and designing a mining technique model using a naïve Bayes classifier. Evaluation of this research employed two methods: accuracy, sensitivity, and specificity calculation as well as an evaluation session with cardiologists and internists. The characteristics of cardiovascular disease are identified by its primary risk factors. Those factors are diabetes mellitus, the level of lipids in the blood, coronary artery function, and kidney function. Class labels were assigned according to the values of these factors: risk level 1, risk level 2 and risk level 3. The evaluation of the classifier performance (accuracy, sensitivity, and specificity) in this research showed that the proposed model predicted the class label of tuples correctly (above 80%). More than eighty percent of respondents (including cardiologists and internists) who participated in the evaluation session agree till strongly agreed that this research followed medical procedures and that the result can support medical analysis related to cardiovascular disease. The research showed that the proposed model achieves good performance for risk level detection of cardiovascular disease.

Four human Plasmodium species quantification using droplet digital PCR.

PubMed

Srisutham, Suttipat; Saralamba, Naowarat; Malleret, Benoit; Rénia, Laurent; Dondorp, Arjen M; Imwong, Mallika

2017-01-01

Droplet digital polymerase chain reaction (ddPCR) is a partial PCR based on water-oil emulsion droplet technology. It is a highly sensitive method for detecting and delineating minor alleles from complex backgrounds and provides absolute quantification of DNA targets. The ddPCR technology has been applied for detection of many pathogens. Here the sensitive assay utilizing ddPCR for detection and quantification of Plasmodium species was investigated. The assay was developed for two levels of detection, genus specific for all Plasmodium species and for specific Plasmodium species detection. The ddPCR assay was developed based on primers and probes specific to the Plasmodium genus 18S rRNA gene. Using ddPCR for ultra-sensitive P. falciparum assessment, the lower level of detection from concentrated DNA obtained from a high volume (1 mL) blood sample was 11 parasites/mL. For species identification, in particular for samples with mixed infections, a duplex reaction was developed for detection and quantification P. falciparum/ P. vivax and P. malariae/ P. ovale. Amplification of each Plasmodium species in the duplex reaction showed equal sensitivity to singleplex single species detection. The duplex ddPCR assay had higher sensitivity to identify minor species in 32 subpatent parasitaemia samples from Cambodia, and performed better than real-time PCR. The ddPCR assay shows high sensitivity to assess very low parasitaemia of all human Plasmodium species. This provides a useful research tool for studying the role of the asymptomatic parasite reservoir for transmission in regions aiming for malaria elimination.

Occurrence of brominated diphenyl ethers, dibenzo-p-dioxins and dibenzofurans in foam materials in scrapped car seats from 1985 to 2012.

PubMed

Redin, L; Niinipuu, M; Jansson, S

2017-03-01

The purpose of this study was to evaluate the occurrence of polybrominated diphenyl ethers (PBDEs), dibenzo-p-dioxins (PBDDs) and dibenzofurans (PBDFs) in polyurethane foam (PUF) from car seats of end-of-life vehicles (ELVs) and compare the concentrations of PBDEs with the stipulated regulations in the POP Directive. The method comprised screening by X-ray fluorescence (XRF) and GG-MS analysis. Of 59 tested samples from ELVs, 17 samples showed lines above limit of detection (LOD) levels when screening by XRF. Those samples were selected as replicates and for further analysis by GC-MS. The majority of the studied samples showed low or non-detectable concentrations of PBDEs and PBDD/Fs, but two samples showed concentrations of Σ Te-HpBDEs close to the regulated level for Te-HpBDEs in waste (1000mgkg -1 ); one was slightly higher (1390mgkg -1 ) and the other slightly lower (570mgkg -1 ). It was concluded that brominated pollutants such as Te-HpBDEs occur in low levels in automotive applications in scrapped cars produced in years when brominated flame retardants were used. However, two of the 59 samples tested showed levels close to those stipulated by regulations concerning POPs in waste. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impact of exopolysaccharide production on functional properties of some Lactobacillus salivarius strains.

PubMed

Mercan, Emin; İspirli, Hümeyra; Sert, Durmuş; Yılmaz, Mustafa Tahsin; Dertli, Enes

2015-11-01

The aim of this work was to characterize functional properties of Lactobacillus salivarius strains isolated from chicken feces. Detection of genes responsible for exopolysaccharide (EPS) production revealed that all strains harbored a dextransucrase gene, but p-gtf gene was only detected in strain E4. Analysis of EPS production levels showed significant alterations among strains tested. Biofilm formation was found to be medium composition dependant, and there was a negative correlation with biofilm formation and EPS production. Autoaggregation properties and coaggregation of L. salivarius strains with chicken pathogens were appeared to be specific at strain level. An increment in bacterial adhesion to chicken gut explants was observed in L. salivarius strains with the reduction in EPS production levels. This study showed that strain-specific properties can determine the functional properties of L. salivarius strains, and the interference of these properties might be crucial for final selection of these strains for technological purposes.

Occurrence of bisphenol A in surface water, drinking water and plasma from Malaysia with exposure assessment from consumption of drinking water.

PubMed

Santhi, V A; Sakai, N; Ahmad, E D; Mustafa, A M

2012-06-15

This study investigated the level of bisphenol A (BPA) in surface water used as potable water, drinking water (tap and bottled mineral water) and human plasma in the Langat River basin, Malaysia. BPA was present in 93% of the surface water samples at levels ranging from below limit of quantification (LOQ; 1.3 ng/L) to 215 ng/L while six fold higher levels were detected in samples collected near industrial and municipal sewage treatment plant outlets. Low levels of BPA were detected in most of the drinking water samples. BPA in tap water ranged from 3.5 to 59.8 ng/L with the highest levels detected in samples collected from taps connected to PVC pipes and water filter devices. Bottled mineral water had lower levels of BPA (3.3±2.6 ng/L) although samples stored in poor storage condition had significantly higher levels (11.3±5.3 ng/L). Meanwhile, only 17% of the plasma samples had detectable levels of BPA ranging from 0.81 to 3.65 ng/mL. The study shows that BPA is a ubiquitous contaminant in surface, tap and bottled mineral water. However, exposure to BPA from drinking water is very low and is less than 0.01% of the tolerable daily intake (TDI). Copyright © 2012 Elsevier B.V. All rights reserved.

Algorithms Based on CWT and Classifiers to Control Cardiac Alterations and Stress Using an ECG and a SCR

PubMed Central

Villarejo, María Viqueira; Zapirain, Begoña García; Zorrilla, Amaia Méndez

2013-01-01

This paper presents the results of using a commercial pulsimeter as an electrocardiogram (ECG) for wireless detection of cardiac alterations and stress levels for home control. For these purposes, signal processing techniques (Continuous Wavelet Transform (CWT) and J48) have been used, respectively. The designed algorithm analyses the ECG signal and is able to detect the heart rate (99.42%), arrhythmia (93.48%) and extrasystoles (99.29%). The detection of stress level is complemented with Skin Conductance Response (SCR), whose success is 94.02%. The heart rate variability does not show added value to the stress detection in this case. With this pulsimeter, it is possible to prevent and detect anomalies for a non-intrusive way associated to a telemedicine system. It is also possible to use it during physical activity due to the fact the CWT minimizes the motion artifacts. PMID:23666135

Algorithms based on CWT and classifiers to control cardiac alterations and stress using an ECG and a SCR.

PubMed

Villarejo, María Viqueira; Zapirain, Begoña García; Zorrilla, Amaia Méndez

2013-05-10

This paper presents the results of using a commercial pulsimeter as an electrocardiogram (ECG) for wireless detection of cardiac alterations and stress levels for home control. For these purposes, signal processing techniques (Continuous Wavelet Transform (CWT) and J48) have been used, respectively. The designed algorithm analyses the ECG signal and is able to detect the heart rate (99.42%), arrhythmia (93.48%) and extrasystoles (99.29%). The detection of stress level is complemented with Skin Conductance Response (SCR), whose success is 94.02%. The heart rate variability does not show added value to the stress detection in this case. With this pulsimeter, it is possible to prevent and detect anomalies for a non-intrusive way associated to a telemedicine system. It is also possible to use it during physical activity due to the fact the CWT minimizes the motion artifacts.

Automatic localization of cerebral cortical malformations using fractal analysis.

PubMed

De Luca, A; Arrigoni, F; Romaniello, R; Triulzi, F M; Peruzzo, D; Bertoldo, A

2016-08-21

Malformations of cortical development (MCDs) encompass a variety of brain disorders affecting the normal development and organization of the brain cortex. The relatively low incidence and the extreme heterogeneity of these disorders hamper the application of classical group level approaches for the detection of lesions. Here, we present a geometrical descriptor for a voxel level analysis based on fractal geometry, then define two similarity measures to detect the lesions at single subject level. The pipeline was applied to 15 normal children and nine pediatric patients affected by MCDs following two criteria, maximum accuracy (WACC) and minimization of false positives (FPR), and proved that our lesion detection algorithm is able to detect and locate abnormalities of the brain cortex with high specificity (WACC  =  85%, FPR  =  96%), sensitivity (WACC  =  83%, FPR  =  63%) and accuracy (WACC  =  85%, FPR  =  90%). The combination of global and local features proves to be effective, making the algorithm suitable for the detection of both focal and diffused malformations. Compared to other existing algorithms, this method shows higher accuracy and sensitivity.

Automatic localization of cerebral cortical malformations using fractal analysis

NASA Astrophysics Data System (ADS)

De Luca, A.; Arrigoni, F.; Romaniello, R.; Triulzi, F. M.; Peruzzo, D.; Bertoldo, A.

2016-08-01

Malformations of cortical development (MCDs) encompass a variety of brain disorders affecting the normal development and organization of the brain cortex. The relatively low incidence and the extreme heterogeneity of these disorders hamper the application of classical group level approaches for the detection of lesions. Here, we present a geometrical descriptor for a voxel level analysis based on fractal geometry, then define two similarity measures to detect the lesions at single subject level. The pipeline was applied to 15 normal children and nine pediatric patients affected by MCDs following two criteria, maximum accuracy (WACC) and minimization of false positives (FPR), and proved that our lesion detection algorithm is able to detect and locate abnormalities of the brain cortex with high specificity (WACC  =  85%, FPR  =  96%), sensitivity (WACC  =  83%, FPR  =  63%) and accuracy (WACC  =  85%, FPR  =  90%). The combination of global and local features proves to be effective, making the algorithm suitable for the detection of both focal and diffused malformations. Compared to other existing algorithms, this method shows higher accuracy and sensitivity.

Robust boundary detection of left ventricles on ultrasound images using ASM-level set method.

PubMed

Zhang, Yaonan; Gao, Yuan; Li, Hong; Teng, Yueyang; Kang, Yan

2015-01-01

Level set method has been widely used in medical image analysis, but it has difficulties when being used in the segmentation of left ventricular (LV) boundaries on echocardiography images because the boundaries are not very distinguish, and the signal-to-noise ratio of echocardiography images is not very high. In this paper, we introduce the Active Shape Model (ASM) into the traditional level set method to enforce shape constraints. It improves the accuracy of boundary detection and makes the evolution more efficient. The experiments conducted on the real cardiac ultrasound image sequences show a positive and promising result.

Evaluating the performance of the quick CSF method in detecting contrast sensitivity function changes

PubMed Central

Hou, Fang; Lesmes, Luis Andres; Kim, Woojae; Gu, Hairong; Pitt, Mark A.; Myung, Jay I.; Lu, Zhong-Lin

2016-01-01

The contrast sensitivity function (CSF) has shown promise as a functional vision endpoint for monitoring the changes in functional vision that accompany eye disease or its treatment. However, detecting CSF changes with precision and efficiency at both the individual and group levels is very challenging. By exploiting the Bayesian foundation of the quick CSF method (Lesmes, Lu, Baek, & Albright, 2010), we developed and evaluated metrics for detecting CSF changes at both the individual and group levels. A 10-letter identification task was used to assess the systematic changes in the CSF measured in three luminance conditions in 112 naïve normal observers. The data from the large sample allowed us to estimate the test–retest reliability of the quick CSF procedure and evaluate its performance in detecting CSF changes at both the individual and group levels. The test–retest reliability reached 0.974 with 50 trials. In 50 trials, the quick CSF method can detect a medium 0.30 log unit area under log CSF change with 94.0% accuracy at the individual observer level. At the group level, a power analysis based on the empirical distribution of CSF changes from the large sample showed that a very small area under log CSF change (0.025 log unit) could be detected by the quick CSF method with 112 observers and 50 trials. These results make it plausible to apply the method to monitor the progression of visual diseases or treatment effects on individual patients and greatly reduce the time, sample size, and costs in clinical trials at the group level. PMID:27120074

Quantitative detection of glucose level based on radiofrequency patch biosensor combined with volume-fixed structures.

PubMed

Qiang, Tian; Wang, Cong; Kim, Nam-Young

2017-12-15

A concept for characterizing a radiofrequency (RF) patch biosensor combined with volume-fixed structures is presented for timely monitoring of an individual's glucose levels based on frequency variation. Two types of patch biosensors-separately integrated with a backside slot (0.53μL) and a front-side tank (0.70μL) structure-were developed to achieve precise and efficient detection while excluding the effects of interference due to the liquidity, shape, and thickness of the tested glucose sample. A glucose test analyte at different concentrations (50-600mg/dL) was dropped into the volume-fixed structures. It fully interacted with the RF patch electromagnetic field, effectively and sensitively changing the resonance frequency and magnitude of the reflection coefficient. Measurement results based on the resonance frequency showed high sensitivity up to 1.13MHz and 1.97MHz per mg/dL, and low detection limits of 26.54mg/dL and 15.22mg/dL, for the two types of patch biosensors, respectively, as well as a short response time of less than 1s. Excellent reusability of the proposed biosensors was verified through three sets of measurements for each individual glucose sample. Regression analysis revealed a good linear correlation between glucose concentrations and the resonance frequency shift. Moreover, to facilitate a multi-parameter-sensitive detection of glucose, the magnitude of the reflection coefficient was also tested, and it showed a good linear correlation with the glucose concentration. Thus, the proposed approach can be adopted for distinguishing glucose solution levels, and it is a potential candidate for early-stage detection of glucose levels in diabetes patients. Copyright © 2017 Elsevier B.V. All rights reserved.

An Organic Decontamination Method for Sampling Devices used in Life-detection Studies

NASA Technical Reports Server (NTRS)

Eigenbrode, Jennifer; Maule, Jake; Wainwright, Norm; Steele, Andrew; Amundsen, Hans E.F.

2008-01-01

Organic decontamination of sampling and storage devices are crucial steps for life-detection, habitability, and ecological investigations of extremophiles living in the most inhospitable niches of Earth, Mars and elsewhere. However, one of the main stumbling blocks for Mars-analogue life-detection studies in terrestrial remote field-sites is the capability to clean instruments and sampling devices to organic levels consistent with null values. Here we present a new seven-step, multi-reagent cleaning and decontamination protocol that was adapted and tested on a glacial ice-coring device and on a rover-guided scoop used for sediment sampling both deployed multiple times during two field seasons of the Arctic Mars Analog Svalbard Expedition AMASE). The effectiveness of the protocols for both devices was tested by (1)in situ metabolic measurements via APT, (2)in situ lipopolysacchride (LPS) quantifications via low-level endotoxin assays, and(3) laboratory-based molecular detection via gas chromatography-mass spectrometry. Our results show that the combination and step-wise application of disinfectants with oxidative and solvation properties for sterilization are effective at removing cellular remnants and other organic traces to levels necessary for molecular organic- and life-detection studies. The validation of this seven-step protocol - specifically for ice sampling - allows us to proceed with confidence in kmskia4 analogue investigations of icy environments. However, results from a rover scoop test showed that this protocol is also suitable for null-level decontamination of sample acquisition devices. Thus, this protocol may be applicable to a variety of sampling devices and analytical instrumentation used for future astrobiology missions to Enceladus, and Europa, as well as for sample-return missions.

Deconvolution single shot multibox detector for supermarket commodity detection and classification

NASA Astrophysics Data System (ADS)

Li, Dejian; Li, Jian; Nie, Binling; Sun, Shouqian

2017-07-01

This paper proposes an image detection model to detect and classify supermarkets shelves' commodity. Based on the principle of the features directly affects the accuracy of the final classification, feature maps are performed to combine high level features with bottom level features. Then set some fixed anchors on those feature maps, finally the label and the position of commodity is generated by doing a box regression and classification. In this work, we proposed a model named Deconvolutiuon Single Shot MultiBox Detector, we evaluated the model using 300 images photographed from real supermarket shelves. Followed the same protocol in other recent methods, the results showed that our model outperformed other baseline methods.

Electrochemical detection of methylated DNA on a microfluidic chip with nanoelectrokinetic pre-concentration.

PubMed

Hong, Sung A; Kim, Yong-June; Kim, Sung Jae; Yang, Sung

2018-06-01

DNA methylation is considered to be a promising marker for the early diagnosis and prognosis of cancer. However, direct detection of the methylated DNAs in clinically relevant samples is still challenging because of its extremely low concentration (~fM). Here, an integrated microfluidic chip is reported, which is capable of pre-concentrating the methylated DNAs using ion concentration polarization (ICP) and electrochemically detecting the pre-concentrated DNAs on a single chip. The proposed chip is the first demonstration of an electrochemical detection of both level and concentration of the methylated DNAs by integrating a DNA pre-concentration unit without gene amplification. Using the proposed chip, 500 fM to 500 nM of methylated DNAs is pre-concentrated by almost 100-fold in 10 min, resulting in a drastic improvement of the electrochemical detection threshold down to the fM level. The proposed chip is able to measure not only the DNA concentration, but also the level of methylation using human urine sample by performing a consecutive electrochemical sensing on a chip. For clinical application, the level as well as the concentration of methylation of glutathione-S transferase-P1 (GSTP1) and EGF-containing fibulin-like extracellular matrix protein 1 (EFEMP1), which are known to be closely associated with prostate cancer diagnosis, are electrochemically detected in human urine spiked with these genes. The developed chip shows a limit of detection (LoD) of 7.9 pM for GSTP1 and 11.8 pM for EFEMP1 and is able to detect the level of methylation in a wide range from 10% to 100% with the concentration variation from 50 pM to 500 nM. Copyright © 2018 Elsevier B.V. All rights reserved.

Molecular population genetics of the insulin/TOR signal transduction pathway: a network-level analysis in Drosophila melanogaster.

PubMed

Alvarez-Ponce, David; Guirao-Rico, Sara; Orengo, Dorcas J; Segarra, Carmen; Rozas, Julio; Aguadé, Montserrat

2012-01-01

The IT-insulin/target of rapamycin (TOR)-signal transduction pathway is a relatively well-characterized pathway that plays a central role in fundamental biological processes. Network-level analyses of DNA divergence in Drosophila and vertebrates have revealed a clear gradient in the levels of purifying selection along this pathway, with the downstream genes being the most constrained. Remarkably, this feature does not result from factors known to affect selective constraint such as gene expression, codon bias, protein length, and connectivity. The present work aims to establish whether the selective constraint gradient detected along the IT pathway at the between-species level can also be observed at a shorter time scale. With this purpose, we have surveyed DNA polymorphism in Drosophila melanogaster and divergence from D. simulans along the IT pathway. Our network-level analysis shows that DNA polymorphism exhibits the same polarity in the strength of purifying selection as previously detected at the divergence level. This equivalent feature detected both within species and between closely and distantly related species points to the action of a general mechanism, whose action is neither organism specific nor evolutionary time dependent. The detected polarity would be, therefore, intrinsic to the IT pathway architecture and function.

Determination of aflatoxin B1 levels in organic spices and herbs.

PubMed

Tosun, Halil; Arslan, Recep

2013-01-01

Organically produced spices and herbs were analyzed for determination of aflatoxin B1 (AFB1) by ELISA using immunoaffinity column. For this purpose 93 organic spices and 37 organic herbs were randomly selected from organic markets and organic shops in Turkey. AFB1 was detected in 58 organic spice and 32 organic herb samples. Among organic spice samples, the maximum value was detected in cinnamon sample (53 μg/kg). AFB1 was not detected in thyme samples. AFB1 levels of 41 organic spice samples were above the EU regulatory limit (5 μg/kg). Among organic herb samples the highest concentration of AFB1 (52.5 μg/kg) was detected in a rosehip sample. AFB1 levels of 21 organic herb samples were above the regulatory limits of the European Union. These results showed that more stringent measures must be taken for the prevention of mold contamination in the production of organic spices and herbs.

Determination of Aflatoxin B1 Levels in Organic Spices and Herbs

PubMed Central

Tosun, Halil; Arslan, Recep

2013-01-01

Organically produced spices and herbs were analyzed for determination of aflatoxin B1 (AFB1) by ELISA using immunoaffinity column. For this purpose 93 organic spices and 37 organic herbs were randomly selected from organic markets and organic shops in Turkey. AFB1 was detected in 58 organic spice and 32 organic herb samples. Among organic spice samples, the maximum value was detected in cinnamon sample (53 μg/kg). AFB1 was not detected in thyme samples. AFB1 levels of 41 organic spice samples were above the EU regulatory limit (5 μg/kg). Among organic herb samples the highest concentration of AFB1 (52.5 μg/kg) was detected in a rosehip sample. AFB1 levels of 21 organic herb samples were above the regulatory limits of the European Union. These results showed that more stringent measures must be taken for the prevention of mold contamination in the production of organic spices and herbs. PMID:23766719

Novel Wearable Device for Blood Leakage Detection during Hemodialysis Using an Array Sensing Patch.

PubMed

Du, Yi-Chun; Lim, Bee-Yen; Ciou, Wei-Siang; Wu, Ming-Jui

2016-06-09

Hemodialysis (HD) is a clinical treatment that requires the puncturing of the body surface. However, needle dislodgement can cause a high risk of blood leakage and can be fatal to patients. Previous studies proposed several devices for blood leakage detection using optical or electrical techniques. Nonetheless, these methods used single-point detection and the design was not suitable for multi-bed monitoring. This study proposed a novel wearable device for blood leakage monitoring during HD using an array sensing patch. The array sensing patch combined with a mapping circuit and a wireless module could measure and transmit risk levels. The different risk levels could improve the working process of healthcare workers, and enhance their work efficiency and reduce inconvenience due to false alarms. Experimental results showed that each point of the sensing array could detect up to 0.1 mL of blood leakage and the array sensing patch supports a risk level monitoring system up to 8 h to alert healthcare personnel of pertinent danger to the patients.

Dynamics of hepatitis C under optimal therapy and sampling based analysis

NASA Astrophysics Data System (ADS)

Pachpute, Gaurav; Chakrabarty, Siddhartha P.

2013-08-01

We examine two models for hepatitis C viral (HCV) dynamics, one for monotherapy with interferon (IFN) and the other for combination therapy with IFN and ribavirin. Optimal therapy for both the models is determined using the steepest gradient method, by defining an objective functional which minimizes infected hepatocyte levels, virion population and side-effects of the drug(s). The optimal therapies for both the models show an initial period of high efficacy, followed by a gradual decline. The period of high efficacy coincides with a significant decrease in the viral load, whereas the efficacy drops after hepatocyte levels are restored. We use the Latin hypercube sampling technique to randomly generate a large number of patient scenarios and study the dynamics of each set under the optimal therapy already determined. Results show an increase in the percentage of responders (indicated by drop in viral load below detection levels) in case of combination therapy (72%) as compared to monotherapy (57%). Statistical tests performed to study correlations between sample parameters and time required for the viral load to fall below detection level, show a strong monotonic correlation with the death rate of infected hepatocytes, identifying it to be an important factor in deciding individual drug regimens.

The estimation method on diffusion spot energy concentration of the detection system

NASA Astrophysics Data System (ADS)

Gao, Wei; Song, Zongxi; Liu, Feng; Dan, Lijun; Sun, Zhonghan; Du, Yunfei

2016-09-01

We propose a method to estimate the diffusion spot energy of the detection system. We do outdoor observation experiments in Xinglong Observatory, by using a detection system which diffusion spot energy concentration is estimated (the correlation coefficient is approximate 0.9926).The aperture of system is 300mm and limiting magnitude of system is 14.15Mv. Observation experiments show that the highest detecting magnitude of estimated system is 13.96Mv, and the average detecting magnitude of estimated system is about 13.5Mv. The results indicate that this method can be used to evaluate the energy diffusion spot concentration level of detection system efficiently.

Attenuation of doxorubicin-induced cardiotoxicity by esculetin through modulation of Bmi-1 expression.

PubMed

Xu, Fan; Li, Xiao; Liu, Lanfang; Xiao, Xu; Zhang, Li; Zhang, Shenglin; Lin, Pingping; Wang, Xiaojie; Wang, Yongwei; Li, Qingshan

2017-09-01

The protective effects and mechanisms of esculetin on doxorubicin (DOX)-induced injury of H9c2 cells were investigated. H9c2 cells were cultured and the logarithmic growth phase of the cells was divided into a control group, a DOX group and an esculetin + DOX group. Cell viability was detected by MTT assay. Annexin V-PI (AV-PI) double staining flow cytometry was carried out to detect cell apoptosis. Intracellular reactive oxygen species (ROS) were detected by flow cytometry. Transmission electron microscope (TEM) was used to evaluate cell ultrastructure. Cleaved caspase-3, cleaved PARP, Bcl-2, Bid and Bmi-1 proteins levels were investigated by western blot analysis. Bmi-1 siRNA was used to detect the role of Bmi-1 in the protective effects of esculetin against DOX-induced toxicity in H9c2 cells. The MTT and AV-PI double staining results showed that esculetin significantly increased H9c2 cell viability. Compared with the control group, the levels of cleaved caspase-3, cleaved PARP, Bid and ROS levels were significantly decreased, but the expression of Bcl-2 and Bmi-1 were significantly increased in the esculetin + DOX group. TEM showed that the cell structure of the mitochondria was protected by esculetin. The results of Bmi-1 siRNA showed that esculetin could protect DOX-induced cardiotoxicity by modulating Bmi-1 expression. Esculetin can protect DOX-induced cardiotoxicity and the effects may be attributable to modulation of Bmi-1 expression, provoking intracellular ROS accumulation, protecting the structure of mitochondria and reducing cell apoptosis.

Effects on health, performance, and tissue residues of the ionophore antibiotic salinomycin in finishing broilers (21 to 38 d).

PubMed

Diaz, Gonzalo J; Aguillón, Yandy; Cortés, Amparo

2018-06-01

A study was conducted to evaluate the effects of feeding salinomycin at the recommended prophylactic level, and at 2 and 3 times this level, to finishing male broilers (d 21 to 38). Four treatment groups were given the experimental diets containing 0, 60, 120, or 180 parts per million (ppm) salinomycin from d 21 to 38. Performance, relative organ weights, selected serum enzymes, and salinomycin residues in liver, muscle, and serum were determined. Salinomycin supplementation had no effect on body weight, feed intake, or feed conversion, and caused no overt signs of toxicity. After a week of being fed the salinomycin diets, the serum activity of aspartate aminotransferase was significantly increased in chickens fed 180 ppm compared with controls. These birds also showed microscopic lesions in breast and thigh muscles, but not in cardiac muscle. Salinomycin residues were not detected by high-performance liquid chromatography coupled to tandem mass spectrometry in liver or muscle samples from the birds fed 0, 60, or 120 ppm salinomycin. However, chickens fed 180 ppm salinomycin had detectable levels in liver and muscle above the maximum residue level of 5 μg/kg established by the European Union. All birds fed salinomycin had salinomycin in their sera with levels ranging from N.D. (not detected) in the controls to 24.4 ± 7.9, 61.4 ± 18.9, and 94.5 ± 9.1 μg/L for salinomycin dietary levels of 60, 120, and 180 ppm, respectively. Serum salinomycin concentration was linearly related with salinomycin content in feed (y = 0.584x - 10, r2 = 0.999). The results showed that even at 3 times the prophylactic level, salinomycin does not induce clinical toxicosis or mortality. No salinomycin residues were found in edible tissues at the recommended dietary level or at 2 times this level. However, salinomycin was detected in serum regardless of the dietary level. A simple method for salinomycin determination in serum is described which can be used as a marker of exposure and/or to predict levels in the diet.

Systematic assessment of the performance of whole-genome amplification for SNP/CNV detection and β-thalassemia genotyping.

PubMed

He, Fei; Zhou, Wanjun; Cai, Ren; Yan, Tizhen; Xu, Xiangmin

2018-04-01

In this study, we aimed to assess the performance of two whole-genome amplification methods, multiple displacement amplification (MDA), and multiple annealing and looping-based amplification cycle (MALBAC), for β-thalassemia genotyping and single-nucleotide polymorphism (SNP)/copy-number variant (CNV) detection using two DNA sequencing assays. We collected peripheral blood, cell lines, and discarded embryos, and carried out MALBAC and MDA on single-cell and five-cell samples. We detected and statistically analyzed differences in the amplification efficiency, positive predictive value, sensitivity, allele dropout (ADO) rate, SNPs, and CV values between the two methods. Through Sanger sequencing at the single-cell and five-cell levels, we showed that both the amplification rate and ADO rate of MDA were better than those using MALBAC, and the sensitivity and positive predictive value obtained from MDA were higher than those from MALBAC for β-thalassemia genotyping. Using next-generation sequencing (NGS) at the single-cell level, we confirmed that MDA has better properties than MALBAC for SNP detection. However, MALBAC was more stable and homogeneous than MDA using low-depth NGS at the single-cell level for CNV detection. We conclude that MALBAC is the better option for CNV detection, while MDA is better suited for SNV detection.

Early detection of nonnative alleles in fish populations: When sample size actually matters

USGS Publications Warehouse

Croce, Patrick Della; Poole, Geoffrey C.; Payne, Robert A.; Gresswell, Bob

2017-01-01

Reliable detection of nonnative alleles is crucial for the conservation of sensitive native fish populations at risk of introgression. Typically, nonnative alleles in a population are detected through the analysis of genetic markers in a sample of individuals. Here we show that common assumptions associated with such analyses yield substantial overestimates of the likelihood of detecting nonnative alleles. We present a revised equation to estimate the likelihood of detecting nonnative alleles in a population with a given level of admixture. The new equation incorporates the effects of the genotypic structure of the sampled population and shows that conventional methods overestimate the likelihood of detection, especially when nonnative or F-1 hybrid individuals are present. Under such circumstances—which are typical of early stages of introgression and therefore most important for conservation efforts—our results show that improved detection of nonnative alleles arises primarily from increasing the number of individuals sampled rather than increasing the number of genetic markers analyzed. Using the revised equation, we describe a new approach to determining the number of individuals to sample and the number of diagnostic markers to analyze when attempting to monitor the arrival of nonnative alleles in native populations.

Edge detection techniques for iris recognition system

NASA Astrophysics Data System (ADS)

Tania, U. T.; Motakabber, S. M. A.; Ibrahimy, M. I.

2013-12-01

Nowadays security and authentication are the major parts of our daily life. Iris is one of the most reliable organ or part of human body which can be used for identification and authentication purpose. To develop an iris authentication algorithm for personal identification, this paper examines two edge detection techniques for iris recognition system. Between the Sobel and the Canny edge detection techniques, the experimental result shows that the Canny's technique has better ability to detect points in a digital image where image gray level changes even at slow rate.

Can spectro-temporal complexity explain the autistic pattern of performance on auditory tasks?

PubMed

Samson, Fabienne; Mottron, Laurent; Jemel, Boutheina; Belin, Pascal; Ciocca, Valter

2006-01-01

To test the hypothesis that level of neural complexity explain the relative level of performance and brain activity in autistic individuals, available behavioural, ERP and imaging findings related to the perception of increasingly complex auditory material under various processing tasks in autism were reviewed. Tasks involving simple material (pure tones) and/or low-level operations (detection, labelling, chord disembedding, detection of pitch changes) show a superior level of performance and shorter ERP latencies. In contrast, tasks involving spectrally- and temporally-dynamic material and/or complex operations (evaluation, attention) are poorly performed by autistics, or generate inferior ERP activity or brain activation. Neural complexity required to perform auditory tasks may therefore explain pattern of performance and activation of autistic individuals during auditory tasks.

Development of a high-sensitivity and portable cell using Helmholtz resonance for noninvasive blood glucose-level measurement based on photoacoustic spectroscopy.

PubMed

Tachibana, K; Okada, K; Kobayashi, R; Ishihara, Y

2016-08-01

We describe the possibility of high-sensitivity noninvasive blood glucose measurement based on photoacoustic spectroscopy (PAS). The demand for noninvasive blood glucose-level measurement has increased due to the explosive increase in diabetic patients. We have developed a noninvasive blood glucose-level measurement based on PAS. The conventional method uses a straight-type resonant cell. However, the cell volume is large, which results in a low detection sensitivity and difficult portability. In this paper, a small-sized Helmholtz-type resonant cell is proposed to improve detection sensitivity and portability by reducing the cell dead volume. First, the acoustic property of the small-sized Helmholtz-type resonant cell was evaluated by performing an experiment using a silicone rubber. As a result, the detection sensitivity of the small-sized Helmholtz-type resonant cell was approximately two times larger than that of the conventional straight-type resonant cell. In addition, the inside volume was approximately 30 times smaller. Second, the detection limits of glucose concentration were estimated by performing an experiment using glucose solutions. The experimental results showed that a glucose concentration of approximately 1% was detected by the small-sized Helmholtz-type resonant cell. Although these results on the sensitivity of blood glucose-level measurement are currently insufficient, they suggest that miniaturization of a resonance cell is effective in the application of noninvasive blood glucose-level measurement.

True and False DRM Memories: Differences Detected with an Implicit Task

PubMed Central

Marini, Maddalena; Agosta, Sara; Mazzoni, Giuliana; Barba, Gianfranco Dalla; Sartori, Giuseppe

2012-01-01

Memory is prone to illusions. When people are presented with lists of words associated with a non-presented critical lure, they produce a high level of false recognitions (false memories) for non-presented related stimuli indistinguishable, at the explicit level, from presented words (DRM paradigm). We assessed whether true and false DRM memories can be distinguished at the implicit level by using the autobiographical IAT (aIAT), a novel method based on indirect measures that permits to detect true autobiographical events encoded in the respondent’s mind/brain. In our experiment, after a DRM task participants performed two aIATs: the first aimed at testing implicit memory for presented words (true-memories aIAT) and the second aimed at evaluating implicit memory for critical lures (false-memories aIAT). Specifically, the two aIATs assessed the association of presented words and critical lures with the logical dimension “true.” Results showed that the aIAT detected a greater association of presented words than critical lures with the logical dimension “true.” This result indicates that although true and false DRM memories are indistinguishable at the explicit level a different association of the true and false DRM memories with the logical dimension “true” can be detected at the implicit level, and suggests that the aIAT may be a sensitive instrument to detect differences between true and false DRM memories. PMID:22969740

Multilevel depth and image fusion for human activity detection.

PubMed

Ni, Bingbing; Pei, Yong; Moulin, Pierre; Yan, Shuicheng

2013-10-01

Recognizing complex human activities usually requires the detection and modeling of individual visual features and the interactions between them. Current methods only rely on the visual features extracted from 2-D images, and therefore often lead to unreliable salient visual feature detection and inaccurate modeling of the interaction context between individual features. In this paper, we show that these problems can be addressed by combining data from a conventional camera and a depth sensor (e.g., Microsoft Kinect). We propose a novel complex activity recognition and localization framework that effectively fuses information from both grayscale and depth image channels at multiple levels of the video processing pipeline. In the individual visual feature detection level, depth-based filters are applied to the detected human/object rectangles to remove false detections. In the next level of interaction modeling, 3-D spatial and temporal contexts among human subjects or objects are extracted by integrating information from both grayscale and depth images. Depth information is also utilized to distinguish different types of indoor scenes. Finally, a latent structural model is developed to integrate the information from multiple levels of video processing for an activity detection. Extensive experiments on two activity recognition benchmarks (one with depth information) and a challenging grayscale + depth human activity database that contains complex interactions between human-human, human-object, and human-surroundings demonstrate the effectiveness of the proposed multilevel grayscale + depth fusion scheme. Higher recognition and localization accuracies are obtained relative to the previous methods.

A Vibration-Based Approach for Stator Winding Fault Diagnosis of Induction Motors: Application of Envelope Analysis

DTIC Science & Technology

2014-10-02

takes it either as auxiliary to magnetic flux, or is not able to detect the winding faults unless severity is already quite significant. This paper...different loads, speeds and severity levels. The experimental results show that the proposed method was able to detect inter-turn faults in the...maintenance strategy requires the technologies of: (a) on- line condition monitoring, (b) fault detection and diagnosis, and (c) prognostics. Figure 1

Application of Cavity Enhanced Absorption Spectroscopy to the Detection of Nitric Oxide, Carbonyl Sulphide, and Ethane—Breath Biomarkers of Serious Diseases

PubMed Central

Wojtas, Jacek

2015-01-01

The paper presents one of the laser absorption spectroscopy techniques as an effective tool for sensitive analysis of trace gas species in human breath. Characterization of nitric oxide, carbonyl sulphide and ethane, and the selection of their absorption lines are described. Experiments with some biomarkers showed that detection of pathogenic changes at the molecular level is possible using this technique. Thanks to cavity enhanced spectroscopy application, detection limits at the ppb-level and short measurements time (<3 s) were achieved. Absorption lines of reference samples of the selected volatile biomarkers were probed using a distributed feedback quantum cascade laser and a tunable laser system consisting of an optical parametric oscillator and difference frequency generator. Setup using the first source provided a detection limit of 30 ppb for nitric oxide and 250 ppb for carbonyl sulphide. During experiments employing a second laser, detection limits of 0.9 ppb and 0.3 ppb were obtained for carbonyl sulphide and ethane, respectively. The conducted experiments show that this type of diagnosis would significantly increase chances for effective therapy of some diseases. Additionally, it offers non-invasive and real time measurements, high sensitivity and selectivity as well as minimizing discomfort for patients. For that reason, such sensors can be used in screening for early detection of serious diseases. PMID:26091398

Application of Cavity Enhanced Absorption Spectroscopy to the Detection of Nitric Oxide, Carbonyl Sulphide, and Ethane--Breath Biomarkers of Serious Diseases.

PubMed

Wojtas, Jacek

2015-06-17

The paper presents one of the laser absorption spectroscopy techniques as an effective tool for sensitive analysis of trace gas species in human breath. Characterization of nitric oxide, carbonyl sulphide and ethane, and the selection of their absorption lines are described. Experiments with some biomarkers showed that detection of pathogenic changes at the molecular level is possible using this technique. Thanks to cavity enhanced spectroscopy application, detection limits at the ppb-level and short measurements time (<3 s) were achieved. Absorption lines of reference samples of the selected volatile biomarkers were probed using a distributed feedback quantum cascade laser and a tunable laser system consisting of an optical parametric oscillator and difference frequency generator. Setup using the first source provided a detection limit of 30 ppb for nitric oxide and 250 ppb for carbonyl sulphide. During experiments employing a second laser, detection limits of 0.9 ppb and 0.3 ppb were obtained for carbonyl sulphide and ethane, respectively. The conducted experiments show that this type of diagnosis would significantly increase chances for effective therapy of some diseases. Additionally, it offers non-invasive and real time measurements, high sensitivity and selectivity as well as minimizing discomfort for patients. For that reason, such sensors can be used in screening for early detection of serious diseases.

West Nile virus 'circulation' in Vojvodina, Serbia: Mosquito, bird, horse and human surveillance.

PubMed

Petrić, Dušan; Petrović, Tamaš; Hrnjaković Cvjetković, Ivana; Zgomba, Marija; Milošević, Vesna; Lazić, Gospava; Ignjatović Ćupina, Aleksandra; Lupulović, Diana; Lazić, Sava; Dondur, Dragan; Vaselek, Slavica; Živulj, Aleksandar; Kisin, Bratislav; Molnar, Tibor; Janku, Djordje; Pudar, Dubravka; Radovanov, Jelena; Kavran, Mihaela; Kovačević, Gordana; Plavšić, Budimir; Jovanović Galović, Aleksandra; Vidić, Milan; Ilić, Svetlana; Petrić, Mina

2017-02-01

Efforts to detect West Nile virus (WNV) in the Vojvodina province, northern Serbia, commenced with human and mosquito surveillance in 2005, followed by horse (2009) and wild bird (2012) surveillance. The knowledge obtained regarding WNV circulation, combined with the need for timely detection of virus activity and risk assessment resulted in the implementation of a national surveillance programme integrating mosquito, horse and bird surveillance in 2014. From 2013, the system showed highly satisfactory results in terms of area specificity (the capacity to indicate the spatial distribution of the risk for human cases of West Nile neuroinvasive disease - WNND) and sensitivity to detect virus circulation even at the enzootic level. A small number (n = 50) of Culex pipiens (pipiens and molestus biotypes, and their hybrids) females analysed per trap/night, combined with a high number of specimens in the sample, provided variable results in the early detection capacity at different administrative levels (NUTS2 versus NUTS3). The clustering of infected mosquitoes, horses, birds and human cases of WNND in 2014-2015 was highly significant, following the south-west to north-east direction in Vojvodina (NUTS2 administrative level). Human WNND cases grouped closest with infected mosquitoes in 2014, and with wild birds/mosquitoes in 2015. In 2014, sentinel horses showed better spatial correspondence with human WNND cases than sentinel chickens. Strong correlations were observed between the vector index values and the incidence of human WNND cases recorded at the NUTS2 and NUTS3 levels. From 2010, West Nile virus was detected in mosquitoes sampled at 43 different trap stations across Vojvodina. At 14 stations (32.56%), WNV was detected in two different (consecutive or alternate) years, at 2 stations in 3 different years, and in 1 station during 5 different years. Based on these results, integrated surveillance will be progressively improved to allow evidence-based adoption of preventive public health and mosquito control measures. Copyright © 2016 Elsevier Ltd. All rights reserved.

Activatable Optical Probes for the Detection of Enzymes

PubMed Central

Drake, Christopher R.; Miller, David C.; Jones, Ella F.

2013-01-01

The early detection of many human diseases is crucial if they are to be treated successfully. Therefore, the development of imaging techniques that can facilitate early detection of disease is of high importance. Changes in the levels of enzyme expression are known to occur in many diseases, making their accurate detection at low concentrations an area of considerable active research. Activatable fluorescent probes show immense promise in this area. If properly designed they should exhibit no signal until they interact with their target enzyme, reducing the level of background fluorescence and potentially endowing them with greater sensitivity. The mechanisms of fluorescence changes in activatable probes vary. This review aims to survey the field of activatable probes, focusing on their mechanisms of action as well as illustrating some of the in vitro and in vivo settings in which they have been employed. PMID:23519774

Object memory and change detection: dissociation as a function of visual and conceptual similarity.

PubMed

Yeh, Yei-Yu; Yang, Cheng-Ta

2008-01-01

People often fail to detect a change between two visual scenes, a phenomenon referred to as change blindness. This study investigates how a post-change object's similarity to the pre-change object influences memory of the pre-change object and affects change detection. The results of Experiment 1 showed that similarity lowered detection sensitivity but did not affect the speed of identifying the pre-change object, suggesting that similarity between the pre- and post-change objects does not degrade the pre-change representation. Identification speed for the pre-change object was faster than naming the new object regardless of detection accuracy. Similarity also decreased detection sensitivity in Experiment 2 but improved the recognition of the pre-change object under both correct detection and detection failure. The similarity effect on recognition was greatly reduced when 20% of each pre-change stimulus was masked by random dots in Experiment 3. Together the results suggest that the level of pre-change representation under detection failure is equivalent to the level under correct detection and that the pre-change representation is almost complete. Similarity lowers detection sensitivity but improves explicit access in recognition. Dissociation arises between recognition and change detection as the two judgments rely on the match-to-mismatch signal and mismatch-to-match signal, respectively.

Simulations and phantom evaluations of magnetic resonance electrical impedance tomography (MREIT) for breast cancer detection

NASA Astrophysics Data System (ADS)

Sadleir, Rosalind J.; Sajib, Saurav Z. K.; Kim, Hyung Joong; Kwon, Oh In; Woo, Eung Je

2013-05-01

MREIT is a new imaging modality that can be used to reconstruct high-resolution conductivity images of the human body. Since conductivity values of cancerous tissues in the breast are significantly higher than those of surrounding normal tissues, breast imaging using MREIT may provide a new noninvasive way of detecting early stage of cancer. In this paper, we present results of experimental and numerical simulation studies of breast MREIT. We built a realistic three-dimensional model of the human breast connected to a simplified model of the chest including the heart and evaluated the ability of MREIT to detect cancerous anomalies in a background material with similar electrical properties to breast tissue. We performed numerical simulations of various scenarios in breast MREIT including assessment of the effects of fat inclusions and effects related to noise levels, such as changing the amplitude of injected currents, effect of added noise and number of averages. Phantom results showed straightforward detection of cancerous anomalies in a background was possible with low currents and few averages. The simulation results showed it should be possible to detect a cancerous anomaly in the breast, while restricting the maximal current density in the heart below published levels for nerve excitation.

Detection of ground motions using high-rate GPS time-series

NASA Astrophysics Data System (ADS)

Psimoulis, Panos A.; Houlié, Nicolas; Habboub, Mohammed; Michel, Clotaire; Rothacher, Markus

2018-05-01

Monitoring surface deformation in real-time help at planning and protecting infrastructures and populations, manage sensitive production (i.e. SEVESO-type) and mitigate long-term consequences of modifications implemented. We present RT-SHAKE, an algorithm developed to detect ground motions associated with landslides, sub-surface collapses, subsidences, earthquakes or rock falls. RT-SHAKE detects first transient changes in individual GPS time series before investigating for spatial correlation(s) of observations made at neighbouring GPS sites and eventually issue a motion warning. In order to assess our algorithm on fast (seconds to minute), large (from 1 cm to meters) and spatially consistent surface motions, we use the 1 Hz GEONET GNSS network data of the Tohoku-Oki MW9.0 2011 as a test scenario. We show the delay of detection of seismic wave arrival by GPS records is of ˜10 seconds with respect to an identical analysis based on strong-motion data and this time delay depends on the level of the time-variable noise. Nevertheless, based on the analysis of the GPS network noise level and ground motion stochastic model, we show that RT-SHAKE can narrow the range of earthquake magnitude, by setting a lower threshold of detected earthquakes to MW6.5-7, if associated with a real-time automatic earthquake location system.

A comparison of high-frequency noise levels on Cascadia Initiative ocean-bottom seismometers

NASA Astrophysics Data System (ADS)

Hilmo, R.; Wilcock, W. S. D.; Roland, E. C.; Bodin, P.; Connolly, J.

2017-12-01

The Cascadia Initiative (CI) included a four-year deployment of 70 ocean bottom seismometers (OBSs) on the Cascadia subduction zone and the Juan de Fuca plate for the purposes of characterizing seismicity and imaging the Earth's interior. The Cascadia subduction zone megathrust exhibits very low rates of seismicity relative to most other subduction zones, and there is great motivation to understand deformation on the megathrust because of its potential to produce a catastrophic M9 earthquake. An understanding of earthquake detectability of the CI network, based on knowledge of noise levels, could contribute to the interpretation of earthquake catalogs derived from the experiment and aid in the design of future networks. This project is aimed at estimating these thresholds of local earthquake detectability and how they change across the array both geographically and temporally. We characterize background noise levels recorded from 0.1 to 20 Hz with an emphasis on the frequency band used to detect local seismicity ( 3-15 Hz) to understand how noise levels depend on instrument design and environmental parameters including seafloor depth, season and oceanographic conditions. Our initial analysis of 3 weeks of vertical channel data in September, January, and May 2012-2013 shows that noise increase significantly moving from the continental shelf to deeper water. Noise levels at a given depth vary with instrument type but further analysis is required to determine whether this reflects variations in instrumental noise and ground coupling noise or errors in the scaling of the instrument response. There is also a strong seasonality in recorded noise levels at some frequencies, with winter noise levels exceeding spring and fall noise levels by up to 10 decibels in both the microseism band and in the fin whale calling band (15-20 Hz). In contrast, the seasonal noise level in the local seismicity band for a given instrument type and location shows smaller noise variation seasonally. We will extend our analysis to the full four-year data set and consider how variations in noise affect the threshold of earthquake detectability by comparing noise levels with expected body wave amplitudes and seismic catalogues.

A visual model for object detection based on active contours and level-set method.

PubMed

Satoh, Shunji

2006-09-01

A visual model for object detection is proposed. In order to make the detection ability comparable with existing technical methods for object detection, an evolution equation of neurons in the model is derived from the computational principle of active contours. The hierarchical structure of the model emerges naturally from the evolution equation. One drawback involved with initial values of active contours is alleviated by introducing and formulating convexity, which is a visual property. Numerical experiments show that the proposed model detects objects with complex topologies and that it is tolerant of noise. A visual attention model is introduced into the proposed model. Other simulations show that the visual properties of the model are consistent with the results of psychological experiments that disclose the relation between figure-ground reversal and visual attention. We also demonstrate that the model tends to perceive smaller regions as figures, which is a characteristic observed in human visual perception.

[Relationship between alcohol dependence and new detected hypertension in adult residents of Xuzhou city].

PubMed

Dong, Zongmei; Lou, Pei'an; Zhang, Pan; Chen, Peipei; Qiao, Cheng; Li, Ting

2015-12-01

To observe the relationship between alcohol dependence and new detected hypertension in adult residents of Xuzhou city. Participants were sampled by stratified multi-stage randomly cluster sampling method from February 2013 to June 2013 among permanent residents aged 18 and more in Xuzhou city. The alcohol dependence was defined with Michigan Alcoholism Screening Test (MAST). Other information was obtained by questionnaire. Spearman correlation analysis and multivariate logistic regression analysis were performed to identify the relationship between alcohol dependence and new detected hypertension. The alcohol dependence rate was 11.56% on the whole cohort (n=36 157), and 22.02%(3 854/17 501) for male and 1.74%(324/18 656) for female(P<0.01). The new detected hypertension rate was 9.46%(3 422/36 157) in the whole cohort. The new detected hypertension rate increased in proportion with the severity of alcohol dependence (P<0.01). Spearman correlation analysis showed that alcohol dependence was positively correlated with systemic blood pressure(r=0.071, P<0.01) and diastolic blood pressure (r=0.077, P<0.01). After adjusting for gender, age, marital status, body mass index, smoking status, physical activity level, educational level, income level and region, multivariate logistic regression analysis showed that alcohol dependence was an independent risk factor for hypertension (low alcohol dependence: OR=1.44, 95%CI 1.14-1.81, P<0.01; light alcohol dependence: OR=1.35, 95%CI 1.11-1.64, P<0.01; medium alcohol dependence: OR=1.83, 95%CI 1.40-2.41, P<0.01). The alcohol dependence is an independent risk factor for new detected hypertension in adult residents of Xuzhou city. Intensive hypertension prevention and treatment strategies should be performed on this population based on our results.

Hsa_circ_0001649: A circular RNA and potential novel biomarker for colorectal cancer.

PubMed

Ji, Wenxin; Qiu, Chunli; Wang, Mao; Mao, Ning; Wu, Shaofeng; Dai, Yinhai

2018-02-26

The circRNAs are differentially expressed in a wide range of cancers in regulating their initiation and progression, and could be used to make a diagnosis for some diseases like tumor as a new biomarker. However, the correlation and the mechanism of action between circRNAs and colorectal cancer (CRC) are still unclear. In this study, by using qRT-PCRs, we detected the expression level of hsa_circ_0001649 in tissue and serum samples from CRC patients, and the cultured cell has been detected. We found that the hsa_circ_0001649 in CRC is significantly lower than the expression level of correspondent nontumorous tissues (n = 64, P < 0.01). We also tested the HCT116 cell lines, and the similar result is observed (n = 15, P < 0.01). Moreover, we detected the serum samples obtained before and after surgery, showing significantly the expression level of hsa_circ_0001649 in the same patient is up-regulated after surgery (n = 18, P < 0.01). Besides, we analyzed the correlation between clinicopathological date and the expression level of hsa_circ_0001649, we found that hsa_circ_0001649 expression level is closely associated with pathological differentiation (P = 0.037), and the result also illustrated that the expression level of hsa_circ_0001649 is no direct correlation with age, gender, TMN stage, lymphatic metastasis, CEA, CA19-9, and CA-724 levels. The area under the receiver operating characteristic (ROC) curve was 0.857. In conclusion, this study showed that the expression level of hsa_circ_0001649 was down-regulated in CRC and could use it as a new biomarker for specific and sensitive inspection of CRC. Copyright © 2018 Elsevier Inc. All rights reserved.

Evaluation of Two Commercial Enzyme-Linked Immunosorbent Assay Kits for the Detection of Human Circulating Metrnl.

PubMed

Zheng, Si-Li; Li, Zhi-Yong; Zhang, Zheng; Wang, Dong-Sheng; Xu, Jian; Miao, Chao-Yu

2018-04-01

Metrnl is a newly discovered secreted protein with neurotrophic activity and metabolic effect, while in earlier studies its circulating level in human was not explored. We evaluated two commercial enzyme-linked immunosorbent assay kits (DY7867-05, R&D Systems and SK00478-02, Aviscera Bioscience) for the detection of human circulating Metrnl. The DY7867-05 kit showed superiority over the SK00478-02 kit since it generated better curve fitting degree, smaller variation among tests, higher inter-assay reproducibility and better specificity, and could effectively detect human Metrnl in six types of blood samples. Subsequent analysis was performed using the DY7867-05 kit. Sample storage conditions were investigated. No gender difference in circulating Metrnl levels was found, while people with newly diagnosed type 2 diabetes mellitus (T2DM) had significantly lower Metrnl levels compared to the healthy controls.

Trace analysis of multi-class pesticide residues in Chinese medicinal health wines using gas chromatography with electron capture detection

PubMed Central

Kong, Wei-Jun; Liu, Qiu-Tao; Kong, Dan-Dan; Liu, Qian-Zhen; Ma, Xin-Ping; Yang, Mei-Hua

2016-01-01

A method is described for multi-residue, high-throughput determination of trace levels of 22 organochlorine pesticides (OCPs) and 5 pyrethroid pesticides (PYPs) in Chinese medicinal (CM) health wines using a QuEChERS (quick, easy, cheap, effective, rugged, and safe) based extraction method and gas chromatography-electron capture detection (GC-ECD). Several parameters were optimized to improve preparation and separation time while still maintaining high sensitivity. Validation tests of spiked samples showed good linearities for 27 pesticides (R = 0.9909–0.9996) over wide concentration ranges. Limits of detection (LODs) and quantification (LOQs) were measured at ng/L levels, 0.06–2 ng/L and 0.2–6 ng/L for OCPs and 0.02–3 ng/L and 0.06–7 ng/L for PYPs, respectively. Inter- and intra-day precision tests showed variations of 0.65–9.89% for OCPs and 0.98–13.99% for PYPs, respectively. Average recoveries were in the range of 47.74–120.31%, with relative standard deviations below 20%. The developed method was then applied to analyze 80 CM wine samples. Beta-BHC (Benzene hexachloride) was the most frequently detected pesticide at concentration levels of 5.67–31.55 mg/L, followed by delta-BHC, trans-chlordane, gamma-BHC, and alpha-BHC. The validated method is simple and economical, with adequate sensitivity for trace levels of multi-class pesticides. It could be adopted by laboratories for this and other types of complex matrices analysis. PMID:26883080

Trace analysis of multi-class pesticide residues in Chinese medicinal health wines using gas chromatography with electron capture detection

NASA Astrophysics Data System (ADS)

Kong, Wei-Jun; Liu, Qiu-Tao; Kong, Dan-Dan; Liu, Qian-Zhen; Ma, Xin-Ping; Yang, Mei-Hua

2016-02-01

A method is described for multi-residue, high-throughput determination of trace levels of 22 organochlorine pesticides (OCPs) and 5 pyrethroid pesticides (PYPs) in Chinese medicinal (CM) health wines using a QuEChERS (quick, easy, cheap, effective, rugged, and safe) based extraction method and gas chromatography-electron capture detection (GC-ECD). Several parameters were optimized to improve preparation and separation time while still maintaining high sensitivity. Validation tests of spiked samples showed good linearities for 27 pesticides (R = 0.9909-0.9996) over wide concentration ranges. Limits of detection (LODs) and quantification (LOQs) were measured at ng/L levels, 0.06-2 ng/L and 0.2-6 ng/L for OCPs and 0.02-3 ng/L and 0.06-7 ng/L for PYPs, respectively. Inter- and intra-day precision tests showed variations of 0.65-9.89% for OCPs and 0.98-13.99% for PYPs, respectively. Average recoveries were in the range of 47.74-120.31%, with relative standard deviations below 20%. The developed method was then applied to analyze 80 CM wine samples. Beta-BHC (Benzene hexachloride) was the most frequently detected pesticide at concentration levels of 5.67-31.55 mg/L, followed by delta-BHC, trans-chlordane, gamma-BHC, and alpha-BHC. The validated method is simple and economical, with adequate sensitivity for trace levels of multi-class pesticides. It could be adopted by laboratories for this and other types of complex matrices analysis.

GraphPrints: Towards a Graph Analytic Method for Network Anomaly Detection

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

Harshaw, Chris R; Bridges, Robert A; Iannacone, Michael D

This paper introduces a novel graph-analytic approach for detecting anomalies in network flow data called \\textit{GraphPrints}. Building on foundational network-mining techniques, our method represents time slices of traffic as a graph, then counts graphlets\\textemdash small induced subgraphs that describe local topology. By performing outlier detection on the sequence of graphlet counts, anomalous intervals of traffic are identified, and furthermore, individual IPs experiencing abnormal behavior are singled-out. Initial testing of GraphPrints is performed on real network data with an implanted anomaly. Evaluation shows false positive rates bounded by 2.84\\% at the time-interval level, and 0.05\\% at the IP-level with 100\\% truemore » positive rates at both.« less

A fibre optic fluorescence sensor to measure redox level in tissues

NASA Astrophysics Data System (ADS)

Zhang, Wen Qi; Morrison, Janna L.; Darby, Jack R. T.; Plush, Sally; Sorvina, Alexandra; Brooks, Doug; Monro, Tanya M.; Afshar Vahid, Shahraam

2018-01-01

We report the design of a fibre optic-based redox detection system for investigating differences in metabolic activities of tissues. Our system shows qualitative agreement with the results collected from a commercial two- photon microscope system. Thus, demonstrating the feasibility of building an ex vivo and in vivo redox detection system that is low cost and portable.

Daytime sea fog retrieval based on GOCI data: a case study over the Yellow Sea.

PubMed

Yuan, Yibo; Qiu, Zhongfeng; Sun, Deyong; Wang, Shengqiang; Yue, Xiaoyuan

2016-01-25

In this paper, a new daytime sea fog detection algorithm has been developed by using Geostationary Ocean Color Imager (GOCI) data. Based on spectral analysis, differences in spectral characteristics were found over different underlying surfaces, which include land, sea, middle/high level clouds, stratus clouds and sea fog. Statistical analysis showed that the Rrc (412 nm) (Rayleigh Corrected Reflectance) of sea fog pixels is approximately 0.1-0.6. Similarly, various band combinations could be used to separate different surfaces. Therefore, three indices (SLDI, MCDI and BSI) were set to discern land/sea, middle/high level clouds and fog/stratus clouds, respectively, from which it was generally easy to extract fog pixels. The remote sensing algorithm was verified using coastal sounding data, which demonstrated that the algorithm had the ability to detect sea fog. The algorithm was then used to monitor an 8-hour sea fog event and the results were consistent with observational data from buoys data deployed near the Sheyang coast (121°E, 34°N). The goal of this study was to establish a daytime sea fog detection algorithm based on GOCI data, which shows promise for detecting fog separately from stratus.

Fast hierarchical knowledge-based approach for human face detection in color images

NASA Astrophysics Data System (ADS)

Jiang, Jun; Gong, Jie; Zhang, Guilin; Hu, Ruolan

2001-09-01

This paper presents a fast hierarchical knowledge-based approach for automatically detecting multi-scale upright faces in still color images. The approach consists of three levels. At the highest level, skin-like regions are determinated by skin model, which is based on the color attributes hue and saturation in HSV color space, as well color attributes red and green in normalized color space. In level 2, a new eye model is devised to select human face candidates in segmented skin-like regions. An important feature of the eye model is that it is independent of the scale of human face. So it is possible for finding human faces in different scale with scanning image only once, and it leads to reduction the computation time of face detection greatly. In level 3, a human face mosaic image model, which is consistent with physical structure features of human face well, is applied to judge whether there are face detects in human face candidate regions. This model includes edge and gray rules. Experiment results show that the approach has high robustness and fast speed. It has wide application perspective at human-computer interactions and visual telephone etc.

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.

Gustatory detection of tetrodotoxin and saxitoxin, and its competitive inhibition by quinine and strychnine in freshwater fishes.

PubMed

Hara, Toshiaki J

2011-01-01

Fish detect extremely low levels of marine toxins tetrodotoxin (TTX) and saxitoxin (STX) via the specialized gustatory receptor(s). Physiological and pharmacological studies show that receptor(s) for TTX and STX are distinct from those which detect feeding stimulant amino acids and bile acids, and that TTX and STX do not share the same receptor populations, while interacting with quinine and strychnine in a competitive fashion suggestive of an antidotal relationship.

Gustatory Detection of Tetrodotoxin and Saxitoxin, and Its Competitive Inhibition by Quinine and Strychnine in Freshwater Fishes

PubMed Central

Hara, Toshiaki J.

2011-01-01

Fish detect extremely low levels of marine toxins tetrodotoxin (TTX) and saxitoxin (STX) via the specialized gustatory receptor(s). Physiological and pharmacological studies show that receptor(s) for TTX and STX are distinct from those which detect feeding stimulant amino acids and bile acids, and that TTX and STX do not share the same receptor populations, while interacting with quinine and strychnine in a competitive fashion suggestive of an antidotal relationship. PMID:22163186

Using 2H labelling to improve the NMR detectability of pyridine and its derivatives by SABRE

PubMed Central

Norcott, Philip; Burns, Michael J.; Rayner, Peter J.; Mewis, Ryan E.

2018-01-01

By introducing a range of 2H labels into pyridine and the para‐substituted agents, methyl isonicotinate and isonicotinamide, we significantly improve their NMR detectability in conjunction with the signal amplification by reversible exchange process. We describe how the rates of T 1 relaxation for the remaining 1H nuclei are increased and show how this leads to a concomitant increase in the level of 1H and 13C hyperpolarization that can ultimately be detected. PMID:29274294

"Reactive" optical sensor for Hg2+ and its application in environmental aqueous media and biological systems.

PubMed

Chen, Zhi; Chen, Jiayun; Pan, Dong; Li, Hongwei; Yao, Yunhui; Lyu, Zu; Yang, Liting; Ma, Li-Jun

2017-03-01

A new rhodamine B-based "reactive" optical sensor (1) for Hg 2+ was synthesized. Sensor 1 shows a unique colorimetric and fluorescent "turn-on" selectivity to Hg 2+ over 14 other metal ions with a hypersensitivity (detection limits are 27.6 nM (5.5 ppb) and 6.9 nM (1.4 ppb), respectively) in neutral buffer solution. To test its applicability in the environment, sensor 1 was applied to quantify and visualize low levels of Hg 2+ in tap water and river water samples. The results indicate sensor 1 is a highly sensitive fluorescent sensor for Hg 2+ with a detection limit of 1.7 ppb in tap water and river water. Moreover, sensor 1 is a convenient visualizing sensor for low levels of Hg 2+ (0.1 ppm) in water environment (from colorless to light pink). In addition, sensor 1 shows good potential as a fluorescent visualizing sensor for Hg 2+ in fetal bovine serum and living 293T cells. The results indicate that sensor 1 shows good potential as a highly sensitive sensor for the detection of Hg 2+ in environmental and biological samples. Graphical Abstract A new rhodamine B-based "reactive" optical sensor (1) for Hg 2+ was synthesized. 1 shows a unique colorimetric and fluorescent "turn-on" selectivity to Hg 2+ over 14 other metal ions with a hypersensitivity in water environment. And it is a convenient visualizing probe for low levels of Hg 2+ in environment aqueous media, fetal bovine serum and living 293T cells.

Intensity and Compactness Enabled Saliency Estimation for Leakage Detection in Diabetic and Malarial Retinopathy.

PubMed

Zhao, Yitian; Zheng, Yalin; Liu, Yonghuai; Yang, Jian; Zhao, Yifan; Chen, Duanduan; Wang, Yongtian

2017-01-01

Leakage in retinal angiography currently is a key feature for confirming the activities of lesions in the management of a wide range of retinal diseases, such as diabetic maculopathy and paediatric malarial retinopathy. This paper proposes a new saliency-based method for the detection of leakage in fluorescein angiography. A superpixel approach is firstly employed to divide the image into meaningful patches (or superpixels) at different levels. Two saliency cues, intensity and compactness, are then proposed for the estimation of the saliency map of each individual superpixel at each level. The saliency maps at different levels over the same cues are fused using an averaging operator. The two saliency maps over different cues are fused using a pixel-wise multiplication operator. Leaking regions are finally detected by thresholding the saliency map followed by a graph-cut segmentation. The proposed method has been validated using the only two publicly available datasets: one for malarial retinopathy and the other for diabetic retinopathy. The experimental results show that it outperforms one of the latest competitors and performs as well as a human expert for leakage detection and outperforms several state-of-the-art methods for saliency detection.

Full Viral Suppression, Low-Level Viremia, and Quantifiable Plasma HIV-RNA at the End of Pregnancy in HIV-Infected Women on Antiretroviral Treatment.

PubMed

Baroncelli, Silvia; Pirillo, Maria F; Tamburrini, Enrica; Guaraldi, Giovanni; Pinnetti, Carmela; Degli Antoni, Anna; Galluzzo, Clementina M; Stentarelli, Chiara; Amici, Roberta; Floridia, Marco

2015-07-01

There is limited information on full viral suppression and low-level HIV-RNA viremia in HIV-infected women at the end of pregnancy. We investigated HIV-RNA levels close to delivery in women on antiretroviral treatment in order to define rates of complete suppression, low-level viremia, and quantifiable HIV-RNA, exploring as potential determinants some clinical and viroimmunological variables. Plasma samples from a national study in Italy, collected between 2003 and 2012, were used. According to plasma HIV-RNA levels, three groups were defined: full suppression (target not detected), low-level viremia (target detected but <37 copies/ml), and quantifiable HIV-RNA (≥37 copies/ml). Multivariable logistic regression was used to define determinants of full viral suppression and of quantifiable HIV-RNA. Among 107 women evaluated at a median gestational age of 35 weeks, 90 (84.1%) had HIV-RNA <37 copies/ml. Most of them (59/90, 65.6%) had full suppression, with the remaining (31/90, 34.4%) showing low-level viremia (median: 11.9 copies/ml; IQR 7.4-16.3). Among the 17 women with quantifiable viral load, median HIV-RNA was 109 copies/ml (IQR 46-251), with only one case showing resistance (mutation M184V; rate: 9.1%). In multivariable analyses, women with higher baseline HIV-RNA levels and with hepatitis C virus (HCV) coinfection were significantly more likely to have quantifiable HIV-RNA in late pregnancy. Full viral suppression was significantly more likely with nonnucleoside reverse transcriptase inhibitor (NNRTI)-based regimens and significantly less likely with higher HIV-RNA in early pregnancy. No cases of HIV transmission occurred. In conclusion, HIV-infected pregnant women showed a high rate of viral suppression and a low resistance rate before delivery. In most cases no target HIV-RNA was detected in plasma, suggesting a low risk of subsequent virological rebound and development of resistance. Women with high levels of HIV-RNA in early pregnancy and those who have concomitant HCV infection should be considered at higher risk of having quantifiable HIV-RNA at the end of pregnancy.

The spatial clustering of obesity: does the built environment matter?

PubMed

Huang, R; Moudon, A V; Cook, A J; Drewnowski, A

2015-12-01

Obesity rates in the USA show distinct geographical patterns. The present study used spatial cluster detection methods and individual-level data to locate obesity clusters and to analyse them in relation to the neighbourhood built environment. The 2008-2009 Seattle Obesity Study provided data on the self-reported height, weight, and sociodemographic characteristics of 1602 King County adults. Home addresses were geocoded. Clusters of high or low body mass index were identified using Anselin's Local Moran's I and a spatial scan statistic with regression models that searched for unmeasured neighbourhood-level factors from residuals, adjusting for measured individual-level covariates. Spatially continuous values of objectively measured features of the local neighbourhood built environment (SmartMaps) were constructed for seven variables obtained from tax rolls and commercial databases. Both the Local Moran's I and a spatial scan statistic identified similar spatial concentrations of obesity. High and low obesity clusters were attenuated after adjusting for age, gender, race, education and income, and they disappeared once neighbourhood residential property values and residential density were included in the model. Using individual-level data to detect obesity clusters with two cluster detection methods, the present study showed that the spatial concentration of obesity was wholly explained by neighbourhood composition and socioeconomic characteristics. These characteristics may serve to more precisely locate obesity prevention and intervention programmes. © 2014 The British Dietetic Association Ltd.

DETECTION OF BACTERIAL CYTOTOXIC ACTIVITIES FROM WATER-DAMAGED CEILING TILE MATERIAL FOLLOWING INCUBATION ON BLOOD AGAR

EPA Science Inventory

Samples of ceiling tiles with high levels of bacteria exhibited cytotoxic activities on a HEP-2 tissue culture assay. Ceiling tiles containing low levels of bacterial colonization did not show cytotoxic activities on the HEP-2 tissue culture assay. Using a spread plate procedure ...

Detection of deep-level defects and reduced carrier concentration in Mg-ion-implanted GaN before high-temperature annealing

NASA Astrophysics Data System (ADS)

Akazawa, Masamichi; Yokota, Naoshige; Uetake, Kei

2018-02-01

We report experimental results for the detection of deep-level defects in GaN after Mg ion implantation before high-temperature annealing. The n-type GaN samples were grown on GaN free-standing substrates by metalorganic vapor phase epitaxy. Mg ions were implanted at 50 keV with a small dosage of 1.5×1011 cm-2, which did not change the conduction type of the n-GaN. By depositing Al2O3 and a Ni/Au electrode onto the implanted n-GaN, metal-oxide-semiconductor (MOS) diodes were fabricated and tested. The measured capacitance-voltage (C-V) characteristics showed a particular behavior with a plateau region and a region with an anomalously steep slope. Fitting to the experimental C-V curves by simulation showed the existence of deep-level defects and a reduction of the carrier concentration near the GaN surface. By annealing at 800oC, the density of the deep-level defects was reduced and the carrier concentration partially recovered.

Quick probabilistic binary image matching: changing the rules of the game

NASA Astrophysics Data System (ADS)

Mustafa, Adnan A. Y.

2016-09-01

A Probabilistic Matching Model for Binary Images (PMMBI) is presented that predicts the probability of matching binary images with any level of similarity. The model relates the number of mappings, the amount of similarity between the images and the detection confidence. We show the advantage of using a probabilistic approach to matching in similarity space as opposed to a linear search in size space. With PMMBI a complete model is available to predict the quick detection of dissimilar binary images. Furthermore, the similarity between the images can be measured to a good degree if the images are highly similar. PMMBI shows that only a few pixels need to be compared to detect dissimilarity between images, as low as two pixels in some cases. PMMBI is image size invariant; images of any size can be matched at the same quick speed. Near-duplicate images can also be detected without much difficulty. We present tests on real images that show the prediction accuracy of the model.

Highly sensitive detection of cancer cells using femtosecond dual-wavelength near-IR two-photon imaging.

PubMed

Starkey, Jean R; Makarov, Nikolay S; Drobizhev, Mikhail; Rebane, Aleksander

2012-07-01

We describe novel imaging protocols that allow detection of small cancer cell colonies deep inside tissue phantoms with high sensitivity and specificity. We compare fluorescence excited in Styryl-9M molecules by femtosecond pulses at near IR wavelengths, where Styryl-9M shows the largest dependence of the two-photon absorption (2PA) cross section on the local environment. We show that by calculating the normalized ratio of the two-photon excited fluorescence (2PEF) intensity at 1200 nm and 1100 nm excitation wavelengths we can achieve high sensitivity and specificity for determining the location of cancer cells surrounded by normal cells. The 2PEF results showed a positive correlation with the levels of MDR1 proteins expressed by the cells, and, for high MDR1 expressors, as few as ten cancer cells could be detected. Similar high sensitivity is also demonstrated for tumor colonies induced in mouse external ears. This technique could be useful in early cancer detection, and, perhaps, also in monitoring dormant cancer deposits.

Antigenemia in Patients with Paracoccidioidomycosis: Detection of the 87-Kilodalton Determinant during and after Antifungal Therapy

PubMed Central

Gómez, B. L.; Figueroa, J. I.; Hamilton, A. J.; Diez, S.; Rojas, M.; Tobón, A. M.; Hay, R. J.; Restrepo, A.

1998-01-01

Serological diagnosis and follow-up of paracoccidioidomycosis (PCM) patients have relied mainly on the detection of antibody responses by using techniques such as complement fixation (CF) and immunodiffusion. We recently described a novel inhibition enzyme-linked immunosorbent assay (inh-ELISA) which proved to be useful in the diagnosis of PCM via the detection of an 87-kDa determinant in patient sera (B. L. Gomez, J. I. Figueroa, A. J. Hamilton, B. Ortiz, M. A. Robledo, R. J. Hay, and A. Restrepo, J. Clin. Microbiol. 35:3278–3283, 1997). This test has now been assessed as a means of following up PCM patients. A total of 24 PCM patients, classified according to their clinical presentation (6 with the acute form of the disease, of whom two had AIDS, 12 with the multifocal form of the disease, and 6 with the unifocal form of the disease), were studied. The four human immunodeficiency virus-negative patients with acute PCM showed a statistically significant decrease in circulating antigen levels after the start of antifungal therapy. Antigen levels in this group became negative by our criteria (≤2.3 μg/ml) before week 20 and remained so in three of four of these patients. In contrast, the two AIDS patients who also presented with the acute form of PCM showed no statistically significant decrease in circulating antigen levels even after 68 weeks of therapy. Taken together as a group, the patients with the multifocal form showed a statistically significant decrease in antigenemia after 28 weeks of therapy. In addition, five of six patients with the unifocal form became antigen negative by week 40. Antigen level decrease mirrored clinical cure in the majority of patients in all clinical groups; in contrast, measurement of anti-PCM antibodies via the CF test showed wide fluctuations in titers during the follow-up period. The inh-ELISA for the detection of the 87-kDa Paracoccidioides brasiliensis determinant would appear to be a valuable additional tool in the follow-up of PCM patients. PMID:9774584

Immunological detection of Fusarium species in cornmeal.

PubMed

Iyer, M S; Cousin, M A

2003-03-01

An indirect enzyme-linked immunosorbent assay (ELISA) was developed to detect Fusarium species in foods. Antibodies to proteins extracted from the mycelia of Fusarium graminearum and Fusarium moniliforme (verticillioides) were produced in New Zealand white rabbits. These antibodies detected 13 Fusarium species in addition to the producer strains. Levels of Fusarium semitectum and Fusarium tricinctum strains were below the detection threshold. The specificity of the assay was tested against 70 molds and yeasts belonging to 23 genera. One strain of Monascus species and one strain of Phoma exigua were detected; however, these two molds are not common contaminants of cereal grains or foods and should not interfere with the assay. The indirect ELISA's detection limits for F. graminearum and F. moniliforme were 0.1 and 1 microg of mold mycelium per ml of a cornmeal mixture, respectively. When spores of each mold were added individually to cornmeal mixtures (at ca. 10 spores per g) and incubated at 25 degrees C, these spores were detected by the indirect ELISA when they reached levels of 10(2) to 10(3) CFU/ml after 24 to 36 h. The indirect ELISA developed here shows promise for the detection of Fusarium species in grains or foods.

The Need and Potential of Biosensors to Detect Dioxins and Dioxin-Like Polychlorinated Biphenyls along the Milk, Eggs and Meat Food Chain

PubMed Central

Chobtang, Jeerasak; de Boer, Imke J. M.; Hoogenboom, Ron L. A. P.; Haasnoot, Willem; Kijlstra, Aize; Meerburg, Bastiaan G.

2011-01-01

Dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) are hazardous toxic, ubiquitous and persistent chemical compounds, which can enter the food chain and accumulate up to higher trophic levels. Their determination requires sophisticated methods, expensive facilities and instruments, well-trained personnel and expensive chemical reagents. Ideally, real-time monitoring using rapid detection methods should be applied to detect possible contamination along the food chain in order to prevent human exposure. Sensor technology may be promising in this respect. This review gives the state of the art for detecting possible contamination with dioxins and DL-PCBs along the food chain of animal-source foods. The main detection methods applied (i.e., high resolution gas-chromatography combined with high resolution mass-spectrometry (HRGC/HRMS) and the chemical activated luciferase gene expression method (CALUX bioassay)), each have their limitations. Biosensors for detecting dioxins and related compounds, although still under development, show potential to overcome these limitations. Immunosensors and biomimetic-based biosensors potentially offer increased selectivity and sensitivity for dioxin and DL-PCB detection, while whole cell-based biosensors present interpretable biological results. The main shortcoming of current biosensors, however, is their detection level: this may be insufficient as limits for dioxins and DL-PCBs for food and feedstuffs are in pg per gram level. In addition, these contaminants are normally present in fat, a difficult matrix for biosensor detection. Therefore, simple and efficient extraction and clean-up procedures are required which may enable biosensors to detect dioxins and DL-PCBs contamination along the food chain. PMID:22247688

The need and potential of biosensors to detect dioxins and dioxin-like polychlorinated biphenyls along the milk, eggs and meat food chain.

PubMed

Chobtang, Jeerasak; de Boer, Imke J M; Hoogenboom, Ron L A P; Haasnoot, Willem; Kijlstra, Aize; Meerburg, Bastiaan G

2011-01-01

Dioxins and dioxin-like polychlorinated biphenyls (DL-PCBs) are hazardous toxic, ubiquitous and persistent chemical compounds, which can enter the food chain and accumulate up to higher trophic levels. Their determination requires sophisticated methods, expensive facilities and instruments, well-trained personnel and expensive chemical reagents. Ideally, real-time monitoring using rapid detection methods should be applied to detect possible contamination along the food chain in order to prevent human exposure. Sensor technology may be promising in this respect. This review gives the state of the art for detecting possible contamination with dioxins and DL-PCBs along the food chain of animal-source foods. The main detection methods applied (i.e., high resolution gas-chromatography combined with high resolution mass-spectrometry (HRGC/HRMS) and the chemical activated luciferase gene expression method (CALUX bioassay)), each have their limitations. Biosensors for detecting dioxins and related compounds, although still under development, show potential to overcome these limitations. Immunosensors and biomimetic-based biosensors potentially offer increased selectivity and sensitivity for dioxin and DL-PCB detection, while whole cell-based biosensors present interpretable biological results. The main shortcoming of current biosensors, however, is their detection level: this may be insufficient as limits for dioxins and DL-PCBs for food and feedstuffs are in pg per gram level. In addition, these contaminants are normally present in fat, a difficult matrix for biosensor detection. Therefore, simple and efficient extraction and clean-up procedures are required which may enable biosensors to detect dioxins and DL-PCBs contamination along the food chain.

Exploring machine-learning-based control plane intrusion detection techniques in software defined optical networks

NASA Astrophysics Data System (ADS)

Zhang, Huibin; Wang, Yuqiao; Chen, Haoran; Zhao, Yongli; Zhang, Jie

2017-12-01

In software defined optical networks (SDON), the centralized control plane may encounter numerous intrusion threatens which compromise the security level of provisioned services. In this paper, the issue of control plane security is studied and two machine-learning-based control plane intrusion detection techniques are proposed for SDON with properly selected features such as bandwidth, route length, etc. We validate the feasibility and efficiency of the proposed techniques by simulations. Results show an accuracy of 83% for intrusion detection can be achieved with the proposed machine-learning-based control plane intrusion detection techniques.

Motion-based video monitoring for early detection of livestock diseases: The case of African swine fever

PubMed Central

Martínez-Avilés, Marta; Ivorra, Benjamin; Martínez-López, Beatriz; Ramos, Ángel Manuel; Sánchez-Vizcaíno, José Manuel

2017-01-01

Early detection of infectious diseases can substantially reduce the health and economic impacts on livestock production. Here we describe a system for monitoring animal activity based on video and data processing techniques, in order to detect slowdown and weakening due to infection with African swine fever (ASF), one of the most significant threats to the pig industry. The system classifies and quantifies motion-based animal behaviour and daily activity in video sequences, allowing automated and non-intrusive surveillance in real-time. The aim of this system is to evaluate significant changes in animals’ motion after being experimentally infected with ASF virus. Indeed, pig mobility declined progressively and fell significantly below pre-infection levels starting at four days after infection at a confidence level of 95%. Furthermore, daily motion decreased in infected animals by approximately 10% before the detection of the disease by clinical signs. These results show the promise of video processing techniques for real-time early detection of livestock infectious diseases. PMID:28877181

Vehicle detection from very-high-resolution (VHR) aerial imagery using attribute belief propagation (ABP)

NASA Astrophysics Data System (ADS)

Wang, Yanli; Li, Ying; Zhang, Li; Huang, Yuchun

2016-10-01

With the popularity of very-high-resolution (VHR) aerial imagery, the shape, color, and context attribute of vehicles are better characterized. Due to the various road surroundings and imaging conditions, vehicle attributes could be adversely affected so that vehicle is mistakenly detected or missed. This paper is motivated to robustly extract the rich attribute feature for detecting the vehicles of VHR imagery under different scenarios. Based on the hierarchical component tree of vehicle context, attribute belief propagation (ABP) is proposed to detect salient vehicles from the statistical perspective. With the Max-tree data structure, the multi-level component tree around the road network is efficiently created. The spatial relationship between vehicle and its belonging context is established with the belief definition of vehicle attribute. To effectively correct single-level belief error, the inter-level belief linkages enforce consistency of belief assignment between corresponding components at different levels. ABP starts from an initial set of vehicle belief calculated by vehicle attribute, and then iterates through each component by applying inter-level belief passing until convergence. The optimal value of vehicle belief of each component is obtained via minimizing its belief function iteratively. The proposed algorithm is tested on a diverse set of VHR imagery acquired in the city and inter-city areas of the West and South China. Experimental results show that the proposed algorithm can detect vehicle efficiently and suppress the erroneous effectively. The proposed ABP framework is promising to robustly classify the vehicles from VHR Aerial imagery.

Ground-based detections of sodium in HD 209458b's atmosphere in two data sets

NASA Astrophysics Data System (ADS)

Albrecht, S.; Snellen, I.; de Mooij, E.; Le Poole, R.

2009-02-01

We present two separate ground-based detections of sodium in the transmission spectrum of HD 209458b. First we reanalyzed an archival data set from the HDS spectrograph on Subaru, which shows sodium at a >5σ level. Secondly, our preliminary results of a UVES/VLT data set indicate sodium absorption at a similar level, although the data cover the eclipse only partially. Both results are fully consistent with the HST results of Charbonneau et al. (2002). The Na D absorption feature seems to be resolved in the narrowest passband.

Assessment of cardiotoxicity during haemopoietic stem cell transplantation with plasma brain natriuretic peptide.

PubMed

Snowden, J A; Hill, G R; Hunt, P; Carnoutsos, S; Spearing, R L; Espiner, E; Hart, D N

2000-08-01

Cardiac failure is a known complication of haemopoietic stem cell transplantation (HSCT) and is often difficult to diagnose as patients may have multiple medical problems. Since brain natriuretic peptide (BNP) is largely a hormone of cardiac ventricular origin and is released early in the course of ventricular dysfunction, we have examined the value of serial plasma BNP levels for detecting cardiac failure in patients undergoing cytotoxic conditioning for HSCT. Fifteen patients undergoing HSCT were evaluated (10 undergoing autologous HSCT; five undergoing allogeneic HSCT). BNP was measured by radioimmunoassay prior to therapy and weekly for 5 weeks. Seven patients had a significant rise in BNP level (above a previously established threshold of 43 pmol/l associated with cardiac failure), occurring 1-4 weeks post commencement of conditioning. In three of these patients, cardiac failure was subsequently diagnosed clinically 3, 9 and 23 days after a BNP level of 43 pmol/l had been detected. These three patients had the highest peak BNP levels for the group and in each case elevation in BNP level occurred for a period exceeding 1 week. Although numbers were relatively small, a BNP >43 pmol/l was significantly associated with the inclusion of high-dose cyclophosphamide in the preparative regimen (P = 0.02). BNP levels showed no relationship to febrile episodes. In conclusion, these results show that plasma BNP may be used as a marker for early detection of cardiac dysfunction in patients undergoing HSCT, particularly if levels are increased for periods exceeding 1 week. Measurement of BNP during HSCT may be helpful in patients at risk of cardiac failure, in complex clinical situations and in monitoring the cardiotoxicity of preparative regimens.

Molecular cloning and characterisation of banana fruit polyphenol oxidase.

PubMed

Gooding, P S; Bird, C; Robinson, S P

2001-09-01

Polyphenol oxidase (PPO; EC 1.10.3.2) is the enzyme thought to be responsible for browning in banana [Musa cavendishii (AAA group, Cavendish subgroup) cv. Williams] fruit. Banana flesh was high in PPO activity throughout growth and ripening. Peel showed high levels of activity early in development but activity declined until ripening started and then remained constant. PPO activity in fruit was not substantially induced after wounding or treatment with 5-methyl jasmonate. Banana flowers and unexpanded leaf roll had high PPO activities with lower activities observed in mature leaves, roots and stem. Four different PPO cDNA clones were amplified from banana fruit (BPO1, BPO11, BPO34 and BPO35). Full-length cDNA and genomic clones were isolated for the most abundant sequence (BPO1) and the genomic clone was found to contain an 85-bp intron. Introns have not been previously found in PPO genes. Northern analysis revealed the presence of BPO1 mRNA in banana flesh early in development but little BPO1 mRNA was detected at the same stage in banana peel. BPO11 transcript was only detected in very young flesh and there was no detectable expression of BPO34 or BPO35 in developing fruit samples. PPO transcripts were also low throughout ripening in both flesh and peel. BPO1 transcripts were readily detected in flowers, stem, roots and leaf roll samples but were not detected in mature leaves. BPO11 showed a similar pattern of expression to BPO1 in these tissues but transcript levels were much lower. BPO34 and BPO35 mRNAs were only detected at a low level in flowers and roots and BPO34 transcript was detected in mature leaves, the only clone to do so. The results suggest that browning of banana fruit during ripening results from release of pre-existing PPO enzyme, which is synthesised very early in fruit development.

Accumulation of steroid hormones in soil and its adjacent aquatic environment from a typical intensive vegetable cultivation of North China.

PubMed

Zhang, Feng-Song; Xie, Yun-Feng; Li, Xue-Wen; Wang, Dai-Yi; Yang, Lin-Sheng; Nie, Zhi-Qiang

2015-12-15

Steroid hormones released from manure agricultural application are a matter of global concern. The residual levels of steroid hormones were studied in a typical intensive vegetable cultivation area in northeast China, with a long history of heavy manure application. Seven steroids (estrone, 17α-estradiol, 17β-estradiol, estriol, testosterone, androstendione and progesterone) were analyzed from soil sampled from vegetable greenhouses, from sediments and water from the adjacent drainage ditch and from the groundwater. The results showed that target steroids were detected in the soil samples, with detection frequencies varying from 3.13 to 100%. The steroid concentrations varied substantially in soils, ranging from below the detection limit to 109.7μg·kg(-1). Three steroids-progesterone, androstendione and estrone-were found to have relatively high residue concentrations in soil, with maximum concentrations of 109.7, 9.83 and 13.30μg·kg(-1), respectively. In adjacent groundwater, all the steroids, with the exception of estrone, were detected in one or more of the 13 groundwater samples. The concentrations of steroids in groundwater ranged from below the method detection limit to 2.38ng·L(-1). Six of the seven (excluding androstendione) were detected in drainage ditch water samples, with concentrations ranging from below the detection limit to 14ng·L(-1). Progesterone, androstendione and estrone accumulated relatively easily in soils; their concentrations in groundwater were lower than those of other steroids. The concentrations of testosterone and estriol were relatively low in soil, while in groundwater were higher than those of other steroids. The residual levels of steroids in soil and groundwater showed a clear spatial variation in the study area. The residual levels of steroid hormones in soil varied substantially between differently planted greenhouses. Copyright © 2015. Published by Elsevier B.V.

Is the detection of accelerated sea level rise imminent?

DOE PAGES

Fasullo, J. T.; Nerem, R. S.; Hamlington, B.

2016-08-10

Global mean sea level rise estimated from satellite altimetry provides a strong constraint on climate variability and change and is expected to accelerate as the rates of both ocean warming and cryospheric mass loss increase over time. In stark contrast to this expectation however, current altimeter products show the rate of sea level rise to have decreased from the first to second decades of the altimeter era. Here, a combined analysis of altimeter data and specially designed climate model simulations shows the 1991 eruption of Mt Pinatubo to likely have masked the acceleration that would have otherwise occurred. This maskingmore » arose largely from a recovery in ocean heat content through the mid to late 1990 s subsequent to major heat content reductions in the years following the eruption. As a result, a consequence of this finding is that barring another major volcanic eruption, a detectable acceleration is likely to emerge from the noise of internal climate variability in the coming decade.« less

Determination of furan levels in commercial samples of baby food from Brazil and preliminary risk assessment.

PubMed

Pavesi Arisseto, A; Vicente, E; De Figueiredo Toledo, M C

2010-08-01

Commercial baby food samples available on the Brazilian market (n = 31) were analysed for furan content using a gas chromatography-mass spectrometry method preceded by solid-phase microextraction. A limit of detection of 0.7 microg kg(-1), a limit of quantitation of 2.4 microg kg(-1), mean recoveries varying from 80% to 107%, and coefficients of variation ranging from 5.6% to 9.4% for repeatability and from 7.4% to 12.4% for within-laboratory reproducibility were obtained during an in-house validation. The levels of furan found in the samples were from not detected to 95.5 microg kg(-1). Samples containing vegetables and meat showed higher furan levels as compared with those containing only fruits. An exposure assessment showed furan intakes up to 2.4 microg kg(-1) body weight day(-1) (99th percentile) for babies fed exclusively with commercial baby foods. Margins of exposure obtained from intakes estimated in this work indicated a potential public health concern.

Lead, cadmium and chromium in raw and boiled portions of Norway lobster.

PubMed

Perugini, Monia; Visciano, Pierina; Manera, Maurizio; Abete, Maria Cesarina; Tarasco, Renata; Amorena, Michele

2014-01-01

Lead, cadmium and chromium levels were determined in different raw and boiled portions of Norway lobster caught in the central Adriatic Sea (Italy). In raw specimens, the lowest concentrations were always detected in the white meat. Lead and cadmium content in the edible portion never exceeded the maximum levels set by European legislation. The highest cadmium and chromium values (0.47 ± 0.04 and 0.62 ± 0.13 mg/kg wet weight, respectively) were detected in the brown meat, while the highest lead concentrations were found in the exoskeleton (0.21 ± 0.01 mg/kg wet weight). Also, the boiled samples showed the lowest metal levels in the white meat, even if a significant increase (p < 0.01) was found for lead and cadmium compared to the corresponding raw portions. Among metals, chromium showed the highest concentrations in both raw and boiled portions, but up to now, the European legislation did not envisage any limits in seafood.

Is the detection of accelerated sea level rise imminent?

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

Fasullo, J. T.; Nerem, R. S.; Hamlington, B.

Global mean sea level rise estimated from satellite altimetry provides a strong constraint on climate variability and change and is expected to accelerate as the rates of both ocean warming and cryospheric mass loss increase over time. In stark contrast to this expectation however, current altimeter products show the rate of sea level rise to have decreased from the first to second decades of the altimeter era. Here, a combined analysis of altimeter data and specially designed climate model simulations shows the 1991 eruption of Mt Pinatubo to likely have masked the acceleration that would have otherwise occurred. This maskingmore » arose largely from a recovery in ocean heat content through the mid to late 1990 s subsequent to major heat content reductions in the years following the eruption. As a result, a consequence of this finding is that barring another major volcanic eruption, a detectable acceleration is likely to emerge from the noise of internal climate variability in the coming decade.« less

Combined 18F-Fluciclovine PET/MRI Shows Potential for Detection and Characterization of High-Risk Prostate Cancer.

PubMed

Elschot, Mattijs; Selnæs, Kirsten M; Sandsmark, Elise; Krüger-Stokke, Brage; Størkersen, Øystein; Giskeødegård, Guro F; Tessem, May-Britt; Moestue, Siver A; Bertilsson, Helena; Bathen, Tone F

2018-05-01

The objective of this study was to investigate whether quantitative imaging features derived from combined 18 F-fluciclovine PET/multiparametric MRI show potential for detection and characterization of primary prostate cancer. Methods: Twenty-eight patients diagnosed with high-risk prostate cancer underwent simultaneous 18 F-fluciclovine PET/MRI before radical prostatectomy. Volumes of interest (VOIs) for prostate tumors, benign prostatic hyperplasia (BPH) nodules, prostatitis, and healthy tissue were delineated on T2-weighted images, using histology as a reference. Tumor VOIs were marked as high-grade (≥Gleason grade group 3) or not. MRI and PET features were extracted on the voxel and VOI levels. Partial least-squared discriminant analysis (PLS-DA) with double leave-one-patient-out cross-validation was performed to distinguish tumors from benign tissue (BPH, prostatitis, or healthy tissue) and high-grade tumors from other tissue (low-grade tumors or benign tissue). The performance levels of PET, MRI, and combined PET/MRI features were compared using the area under the receiver-operating-characteristic curve (AUC). Results: Voxel and VOI features were extracted from 40 tumor VOIs (26 high-grade), 36 BPH VOIs, 6 prostatitis VOIs, and 37 healthy-tissue VOIs. PET/MRI performed better than MRI and PET alone for distinguishing tumors from benign tissue (AUCs of 87%, 81%, and 83%, respectively, at the voxel level and 96%, 93%, and 93%, respectively, at the VOI level) and high-grade tumors from other tissue (AUCs of 85%, 79%, and 81%, respectively, at the voxel level and 93%, 93%, and 91%, respectively, at the VOI level). T2-weighted MRI, diffusion-weighted MRI, and PET features were the most important for classification. Conclusion: Combined 18 F-fluciclovine PET/multiparametric MRI shows potential for improving detection and characterization of high-risk prostate cancer, in comparison to MRI and PET alone. © 2018 by the Society of Nuclear Medicine and Molecular Imaging.

Novel Wearable Device for Blood Leakage Detection during Hemodialysis Using an Array Sensing Patch

PubMed Central

Du, Yi-Chun; Lim, Bee-Yen; Ciou, Wei-Siang; Wu, Ming-Jui

2016-01-01

Hemodialysis (HD) is a clinical treatment that requires the puncturing of the body surface. However, needle dislodgement can cause a high risk of blood leakage and can be fatal to patients. Previous studies proposed several devices for blood leakage detection using optical or electrical techniques. Nonetheless, these methods used single-point detection and the design was not suitable for multi-bed monitoring. This study proposed a novel wearable device for blood leakage monitoring during HD using an array sensing patch. The array sensing patch combined with a mapping circuit and a wireless module could measure and transmit risk levels. The different risk levels could improve the working process of healthcare workers, and enhance their work efficiency and reduce inconvenience due to false alarms. Experimental results showed that each point of the sensing array could detect up to 0.1 mL of blood leakage and the array sensing patch supports a risk level monitoring system up to 8 h to alert healthcare personnel of pertinent danger to the patients. PMID:27294927

Proposal and Implementation of a Robust Sensing Method for DVB-T Signal

NASA Astrophysics Data System (ADS)

Song, Chunyi; Rahman, Mohammad Azizur; Harada, Hiroshi

This paper proposes a sensing method for TV signals of DVB-T standard to realize effective TV White Space (TVWS) Communication. In the TVWS technology trial organized by the Infocomm Development Authority (iDA) of Singapore, with regard to the sensing level and sensing time, detecting DVB-T signal at the level of -120dBm over an 8MHz channel with a sensing time below 1 second is required. To fulfill such a strict sensing requirement, we propose a smart sensing method which combines feature detection and energy detection (CFED), and is also characterized by using dynamic threshold selection (DTS) based on a threshold table to improve sensing robustness to noise uncertainty. The DTS based CFED (DTS-CFED) is evaluated by computer simulations and is also implemented into a hardware sensing prototype. The results show that the DTS-CFED achieves a detection probability above 0.9 for a target false alarm probability of 0.1 for DVB-T signals at the level of -120dBm over an 8MHz channel with the sensing time equals to 0.1 second.

Geological Carbon Sequestration: A New Approach for Near-Surface Assurance Monitoring

PubMed Central

Wielopolski, Lucian

2011-01-01

There are two distinct objectives in monitoring geological carbon sequestration (GCS): Deep monitoring of the reservoir’s integrity and plume movement and near-surface monitoring (NSM) to ensure public health and the safety of the environment. However, the minimum detection limits of the current instrumentation for NSM is too high for detecting weak signals that are embedded in the background levels of the natural variations, and the data obtained represents point measurements in space and time. A new approach for NSM, based on gamma-ray spectroscopy induced by inelastic neutron scatterings (INS), offers novel and unique characteristics providing the following: (1) High sensitivity with a reducible error of measurement and detection limits, and, (2) temporal- and spatial-integration of carbon in soil that results from underground CO2 seepage. Preliminary field results validated this approach showing carbon suppression of 14% in the first year and 7% in the second year. In addition the temporal behavior of the error propagation is presented and it is shown that for a signal at the level of the minimum detection level the error asymptotically approaches 47%. PMID:21556180

Uric acid promotes oxidative stress and enhances vascular endothelial cell apoptosis in rats with middle cerebral artery occlusion.

PubMed

Song, Chengfu; Zhao, Xiangdong

2018-05-15

In patients with cerebral infarction (CI), elevated serum uric acid (UA) level may exacerbate the occurrence and development of carotid atherosclerosis (AS). Our study intended to explore the underlying mechanism. We enrolled 86 patients with CI, and divided them into four groups: Non-AS, AS-mild, AS-moderate, and AS-severe groups; the levels of UA and oxidative stress-related factors in serum were detected. The middle cerebral artery occlusion (MCAO) model was used to stimulate CI in rats, and different doses of UA were administrated. The levels of oxidative stress-related factors in serum were detected. Hematoxylin & eosin (H&E) staining was used to observe the morphological alterations, and the apoptotic cell death detection kit was used to detect apoptotic cells. Increased UA concentration and enhanced oxidative stress were found in AS patients. H&E staining results showed that UA treatment exacerbated morphological damage in rats with MCAO, promoted oxidative stress, and enhanced vascular endothelial cell apoptosis in rats with MCAO. © 2017 The Author(s).

Real-time distributed fiber optic sensor for security systems: Performance, event classification and nuisance mitigation

NASA Astrophysics Data System (ADS)

Mahmoud, Seedahmed S.; Visagathilagar, Yuvaraja; Katsifolis, Jim

2012-09-01

The success of any perimeter intrusion detection system depends on three important performance parameters: the probability of detection (POD), the nuisance alarm rate (NAR), and the false alarm rate (FAR). The most fundamental parameter, POD, is normally related to a number of factors such as the event of interest, the sensitivity of the sensor, the installation quality of the system, and the reliability of the sensing equipment. The suppression of nuisance alarms without degrading sensitivity in fiber optic intrusion detection systems is key to maintaining acceptable performance. Signal processing algorithms that maintain the POD and eliminate nuisance alarms are crucial for achieving this. In this paper, a robust event classification system using supervised neural networks together with a level crossings (LCs) based feature extraction algorithm is presented for the detection and recognition of intrusion and non-intrusion events in a fence-based fiber-optic intrusion detection system. A level crossings algorithm is also used with a dynamic threshold to suppress torrential rain-induced nuisance alarms in a fence system. Results show that rain-induced nuisance alarms can be suppressed for rainfall rates in excess of 100 mm/hr with the simultaneous detection of intrusion events. The use of a level crossing based detection and novel classification algorithm is also presented for a buried pipeline fiber optic intrusion detection system for the suppression of nuisance events and discrimination of intrusion events. The sensor employed for both types of systems is a distributed bidirectional fiber-optic Mach-Zehnder (MZ) interferometer.

Glyphosate and AMPA of agricultural soil, surface water, groundwater and sediments in areas prevalent with chronic kidney disease of unknown etiology, Sri Lanka.

PubMed

Gunarathna, Shankani; Gunawardana, Buddhika; Jayaweera, Mahesh; Manatunge, Jagath; Zoysa, Kasun

2018-06-08

Glyphosate, which is commercially available as Roundup®, was the widely used herbicide in Sri Lanka until 2015 and is suspected to be one of the causal factors for Chronic Kidney Disease of unknown etiology (CKDu). This research, therefore, aims at studying the presence of glyphosate and Aminomethylphosphonic acid (AMPA) in different environmental matrices in CKDu prevalent areas. Topsoil samples from agricultural fields, water samples from nearby shallow wells and lakes, and sediment samples from lakes were collected and analyzed for glyphosate and AMPA using the LC/MS. Glyphosate (270-690 µg/kg) and AMPA (2-8 µg/kg) were detected in all soil samples. Amorphous iron oxides and organic matter content of topsoil showed a strong and a moderate positive linear relationship with glyphosate. The glyphosate and inorganic phosphate levels in topsoil had a strong negative significant linear relationship. Presence of high valence cations such as Fe 3+ and Al 3+ in topsoil resulted in the formation of glyphosate-metal complexes, thus strong retention of glyphosate in soil. Lower levels of AMPA than the corresponding glyphosate levels in topsoil could be attributed to factors such as the strong adsorption capacity of glyphosate to soil and higher LOQ in the quantification of AMPA. The glyphosate levels of lakes were between 28 to 45 µg/L; no AMPA was detected. While trace levels of glyphosate (1-4 µg/L) were detected in all groundwater samples, AMPA (2-11µg/L) was detected only in four out of nine samples. Glyphosate was detected in all sediment samples (85-1000 µg/kg), and a strong linear relationship with the organic matter content was observed. AMPA was detected (1-15 µg/kg) in seven out of nine sediment samples. It could be inferred that the impact on CKDu by the levels of glyphosate and AMPA detected in the study area is marginal when compared with the MCL of the USEPA (700 µg/L).

Plasma and serum from nonfasting men and women differ in their lipidomic profiles.

PubMed

Ishikawa, Masaki; Tajima, Yoko; Murayama, Mayumi; Senoo, Yuya; Maekawa, Keiko; Saito, Yoshiro

2013-01-01

Biomarkers will play important roles in disease diagnosis, drug development, and the proper use of drugs. Blood is considered the best biofluid for biomarker research because it is easy to access and a wealth of data are available. However, previous studies revealed that several ionic metabolites showed different levels (including presence or absence) in plasma and serum. Thus, attention should be paid to selecting the best biofluid for biomarker exploration. Many lipid molecules have biological significance and thus would be candidate biomarkers. However, no comprehensive study revealing differences in lipid metabolite levels between plasma and serum has been undertaken. Furthermore, gender differences have not been reported. To clarify the difference in the levels of lipid metabolites between human plasma and serum from both genders, we performed lipid metabolomic analysis using liquid chromatography-mass spectrometry-based systems for phospholipids (PLs), lysoPLs, sphingomyelins, ceramides and oxidative fatty acids. Our results revealed that most of the lipid metabolites were present at similar levels in plasma and serum and in males and females. However, several oxidative fatty acid metabolites showed differences. Of the metabolites related to clotting processes, three showed higher levels in serum than in plasma, and three were detected only in serum. Furthermore, four metabolites were present at different levels between males and females, and two were detected only in males. Thus, attention should be paid to the selection of plasma or serum when utilizing these lipid metabolites as biomarkers.

Study of the cross-contamination and survival of Salmonella in fresh apples.

PubMed

Perez-Rodriguez, F; Begum, M; Johannessen, G S

2014-08-01

The present work aimed at studying the cross contamination of apples by Salmonella during the processing of commercial fresh apples and its survival capacity on apple at room temperature. For the first study, the typical process of fresh apples was simulated at laboratory scale in which an apple that was artificially contaminated by Salmonella at different concentration levels (8, 6 and 5 log cfu/apple) was introduced in one batch and processed including a simulated transport/washing step and drying step using sponges to simulate the porous material used in the industry. Results indicated that at 8 log cfu/apple, 50% fresh apples were contaminated after processing, with all analysed environmental samples being positive for the pathogen, consisting of washing water and sponges. However, at lower inoculum levels (5-6 log cfu/apple) no cross contamination was detected in apples, and only environmental samples showed contamination by Salmonella after processing including both water and sponges. Experiments on the survival of Salmonella on apple showed that the pathogen was capable to survive for 12 days, only showing a significant drop at the end of the experiment. Finally, two-class attribute sampling plans were assessed as tool to detect Salmonella in different contamination scenarios in fresh apple. This analysis indicated that with the highest inoculum level, a total of 16 apples would be needed to reach 95% of detecting Salmonella (i.e. lot rejection). In turn, when low levels were assessed (5-6 log cfu/apple), a large number of apples (n=1021) would have to be sampled to obtain the same confidence level (95%). If the environment is sampled (i.e. water and sponges), a lower number of samples would be needed to detect the pathogen. However, the feasibility of environmental sampling has not been assessed from a practical point of view. Overall, the results in this study evidenced that cross contamination by Salmonella might occur during processing of fresh apples and subsequently, the pathogen might survive for a noticeable period of time. Copyright © 2014 Elsevier B.V. All rights reserved.

Stochastic performance modeling and evaluation of obstacle detectability with imaging range sensors

NASA Technical Reports Server (NTRS)

Matthies, Larry; Grandjean, Pierrick

1993-01-01

Statistical modeling and evaluation of the performance of obstacle detection systems for Unmanned Ground Vehicles (UGVs) is essential for the design, evaluation, and comparison of sensor systems. In this report, we address this issue for imaging range sensors by dividing the evaluation problem into two levels: quality of the range data itself and quality of the obstacle detection algorithms applied to the range data. We review existing models of the quality of range data from stereo vision and AM-CW LADAR, then use these to derive a new model for the quality of a simple obstacle detection algorithm. This model predicts the probability of detecting obstacles and the probability of false alarms, as a function of the size and distance of the obstacle, the resolution of the sensor, and the level of noise in the range data. We evaluate these models experimentally using range data from stereo image pairs of a gravel road with known obstacles at several distances. The results show that the approach is a promising tool for predicting and evaluating the performance of obstacle detection with imaging range sensors.

Observations of temporal change of nighttime cloud cover from Himawari 8 and ground-based sky camera over Chiba, Japan

NASA Astrophysics Data System (ADS)

Lagrosas, N.; Gacal, G. F. B.; Kuze, H.

2017-12-01

Detection of nighttime cloud from Himawari 8 is implemented using the difference of digital numbers from bands 13 (10.4µm) and 7 (3.9µm). The digital number difference of -1.39x104 can be used as a threshold to separate clouds from clear sky conditions. To look at observations from the ground over Chiba, a digital camera (Canon Powershot A2300) is used to take images of the sky every 5 minutes at an exposure time of 5s at the Center for Environmental Remote Sensing, Chiba University. From these images, cloud cover values are obtained using threshold algorithm (Gacal, et al, 2016). Ten minute nighttime cloud cover values from these two datasets are compared and analyzed from 29 May to 05 June 2017 (20:00-03:00 JST). When compared with lidar data, the camera can detect thick high level clouds up to 10km. The results show that during clear sky conditions (02-03 June), both camera and satellite cloud cover values show 0% cloud cover. During cloudy conditions (05-06 June), the camera shows almost 100% cloud cover while satellite cloud cover values range from 60 to 100%. These low values can be attributed to the presence of low-level thin clouds ( 2km above the ground) as observed from National Institute for Environmental Studies lidar located inside Chiba University. This difference of cloud cover values shows that the camera can produce accurate cloud cover values of low level clouds that are sometimes not detected by satellites. The opposite occurs when high level clouds are present (01-02 June). Derived satellite cloud cover shows almost 100% during the whole night while ground-based camera shows cloud cover values that range from 10 to 100% during the same time interval. The fluctuating values can be attributed to the presence of thin clouds located at around 6km from the ground and the presence of low level clouds ( 1km). Since the camera relies on the reflected city lights, it is possible that the high level thin clouds are not observed by the camera but is observed by the satellite. Also, this condition constitutes layers of clouds that are not observed by each camera. The results of this study show that one instrument can be used to correct each other to provide better cloud cover values. These corrections is dependent on the height and thickness of the clouds. No correction is necessary when the sky is clear.

Detection of Low-Level Cardinium and Wolbachia Infections in Culicoides

PubMed Central

Mee, Peter T.; Weeks, Andrew R.; Walker, Peter J.; Hoffmann, Ary A.

2015-01-01

Bacterial endosymbionts have been identified as potentially useful biological control agents for a range of invertebrate vectors of disease. Previous studies of Culicoides (Diptera: Ceratopogonidae) species using conventional PCR assays have provided evidence of Wolbachia (1/33) and Cardinium (8/33) infections. Here, we screened 20 species of Culicoides for Wolbachia and Cardinium, utilizing a combination of conventional PCR and more sensitive quantitative PCR (qPCR) assays. Low levels of Cardinium DNA were detected in females of all but one of the Culicoides species screened, and low levels of Wolbachia were detected in females of 9 of the 20 Culicoides species. Sequence analysis based on partial 16S rRNA gene and gyrB sequences identified “Candidatus Cardinium hertigii” from group C, which has previously been identified in Culicoides from Japan, Israel, and the United Kingdom. Wolbachia strains detected in this study showed 98 to 99% sequence identity to Wolbachia previously detected from Culicoides based on the 16S rRNA gene, whereas a strain with a novel wsp sequence was identified in Culicoides narrabeenensis. Cardinium isolates grouped to geographical regions independent of the host Culicoides species, suggesting possible geographical barriers to Cardinium movement. Screening also identified Asaia bacteria in Culicoides. These findings point to a diversity of low-level endosymbiont infections in Culicoides, providing candidates for further characterization and highlighting the widespread occurrence of these endosymbionts in this insect group. PMID:26150447

Changes in laboratory test results and diagnostic imaging presentation before the detection of occupational cholangiocarcinoma.

PubMed

Kubo, Shoji; Takemura, Shigekazu; Sakata, Chikaharu; Urata, Yorihisa; Nishioka, Takayoshi; Nozawa, Akinori; Kinoshita, Masahiko; Hamano, Genya; Nakanuma, Yasuni; Endo, Ginji

2014-01-01

A cholangiocarcinoma outbreak among workers of an offset color proof-printing department in a printing company was recently reported. It is important to understand the clinical course leading to occupational cholangiocarcinoma development for investigation of the carcinogenesis process and for surveillance and early detection. We evaluated the changes in laboratory test results and diagnostic imaging presentation before the detection of cholangiocarcinoma. We investigated the changes in laboratory test results and diagnostic imaging presentation before the detection of cholangiocarcinoma in 2 patients because the data were available. Results The clinical courses observed in the 2 participating patients showed persistent elevation of serum γ-glutamyl transpeptidase levels with or without elevated serum levels of alanine aminotransferase and/or aspartate aminotransferase before cholangiocarcinoma detection. Dilatation of the bile ducts without tumor-induced stenosis was observed several years before cholangiocarcinoma detection and progressed gradually in both patients. The serum concentration of carbohydrate 19-9 also increased prior to cholangiocarcinoma detection in both patients. Eventually, observation of stenosis of the bile duct and a space-occupying lesion strongly suggested cholangiocarcinoma. Pathological examination of the resected specimens showed chronic bile duct injury and neoplastic lesions, such as "biliary intraepithelial neoplasia" and "intraductal papillary neoplasm of the bile duct" in various sites of the bile ducts, particularly in the dilated bile ducts. The changes in laboratory test results and diagnostic imaging might be related to the development of cholangiocarcinoma. It is important to monitor diagnostic imaging presentation and laboratory test results in workers with extended exposure to organic solvents.

Radiation Measurements During Trip From Earth to Mars

NASA Image and Video Library

2013-05-30

This graphic shows the level of natural radiation detected by the Radiation Assessment Detector shielded inside NASA Mars Science Laboratory on the trip from Earth to Mars from December 2011 to July 2012.

Hierarchical effects on target detection and conflict monitoring

PubMed Central

Cao, Bihua; Gao, Feng; Ren, Maofang; Li, Fuhong

2016-01-01

Previous neuroimaging studies have demonstrated a hierarchical functional structure of the frontal cortices of the human brain, but the temporal course and the electrophysiological signature of the hierarchical representation remains unaddressed. In the present study, twenty-one volunteers were asked to perform a nested cue-target task, while their scalp potentials were recorded. The results showed that: (1) in comparison with the lower-level hierarchical targets, the higher-level targets elicited a larger N2 component (220–350 ms) at the frontal sites, and a smaller P3 component (350–500 ms) across the frontal and parietal sites; (2) conflict-related negativity (non-target minus target) was greater for the lower-level hierarchy than the higher-level, reflecting a more intensive process of conflict monitoring at the final step of target detection. These results imply that decision making, context updating, and conflict monitoring differ among different hierarchical levels of abstraction. PMID:27561989

Detection of dual-band infrared small target based on joint dynamic sparse representation

NASA Astrophysics Data System (ADS)

Zhou, Jinwei; Li, Jicheng; Shi, Zhiguang; Lu, Xiaowei; Ren, Dongwei

2015-10-01

Infrared small target detection is a crucial and yet still is a difficult issue in aeronautic and astronautic applications. Sparse representation is an important mathematic tool and has been used extensively in image processing in recent years. Joint sparse representation is applied in dual-band infrared dim target detection in this paper. Firstly, according to the characters of dim targets in dual-band infrared images, 2-dimension Gaussian intensity model was used to construct target dictionary, then the dictionary was classified into different sub-classes according to different positions of Gaussian function's center point in image block; The fact that dual-band small targets detection can use the same dictionary and the sparsity doesn't lie in atom-level but in sub-class level was utilized, hence the detection of targets in dual-band infrared images was converted to be a joint dynamic sparse representation problem. And the dynamic active sets were used to describe the sparse constraint of coefficients. Two modified sparsity concentration index (SCI) criteria was proposed to evaluate whether targets exist in the images. In experiments, it shows that the proposed algorithm can achieve better detecting performance and dual-band detection is much more robust to noise compared with single-band detection. Moreover, the proposed method can be expanded to multi-spectrum small target detection.

Determination of phenol compounds in surface water matrices by bar adsorptive microextraction-high performance liquid chromatography-diode array detection.

PubMed

Neng, Nuno R; Nogueira, José M F

2014-07-03

Bar adsorptive microextraction combined with liquid desorption followed by high performance liquid chromatography with diode array detection (BAµE-LD/HPLC-DAD) is proposed for the determination of trace levels of five phenol compounds (3-nitrophenol, 4-nitrophenol, bisphenol-A, 4-n-octylphenol and 4-n-nonylphenol) in surface water matrices. By using a polystyrene-divinylbenzene copolymer (PS-DVB) sorbent phase, high selectivity and efficiency is achieved even against polydimethylsiloxane through stir bar sorptive extraction. Assays performed by BAµE(PS-DVB)-LD/HPLC-DAD on 25 mL water samples spiked at the 10.0 µg/L levels yielded recoveries over 88.0%±5.7% for all five analytes, under optimized experimental conditions. The analytical performance showed good precision (RSD<15%), detection limits of 0.25 µg/L and linear dynamic ranges (1.0-25.0 μg/L) with determination coefficient higher than 0.9904. By using the standard addition method, the application of the present method to surface water matrices allowed very good performances at the trace level. The proposed methodology proved to be a suitable alternative to monitor phenol compounds in surface water matrices, showing to be easy to implement, reliable, sensitive and requiring a low sample volume.

CSF levels of oligomeric alpha-synuclein and beta-amyloid as biomarkers for neurodegenerative disease

PubMed Central

Chatterjee, Gaurav; McGraw, Claire; Kasturirangan, Srinath; Schulz, Philip

2012-01-01

Protein misfolding and aggregation is a critically important feature in many devastating neurodegenerative diseases, therefore characterization of the CSF concentration profiles of selected key forms and morphologies of proteins involved in these diseases, including β-amyloid (Aβ) and α-synuclein (a-syn), can be an effective diagnostic assay for these diseases. CSF levels of tau and Aβ have been shown to have great promise as biomarkers for Alzheimer’s disease. However since the onset and progression of many neurodegenerative diseases have been strongly correlated with the presence of soluble oligomeric aggregates of proteins including various Aβ and a-syn aggregate species, specific detection and quantification of levels of each of these different toxic protein species in CSF may provide a simple and accurate means to presymptomatically diagnose and distinguish between these diseases. Here we show that the presence of different protein morphologies in human CSF samples can be readily detected using highly selective morphology specific reagents in conjunction with a sensitive electronic biosensor. We further show that these morphology specific reagents can readily distinguish between post-mortem CSF samples from AD, PD and cognitively normal sources. These studies suggest that detection of specific oligomeric aggregate species holds great promise as sensitive biomarkers for neurodegenerative disease. PMID:22076255

Reliability of semiquantitative assessment of osteophytes and subchondral cysts on tomosynthesis images by radiologists with different levels of expertise.

PubMed

Hayashi, Daichi; Xu, Li; Gusenburg, Jeffrey; Roemer, Frank W; Hunter, David J; Li, Ling; Guermazi, Ali

2014-01-01

We aimed to assess reliability of the evaluation of osteophytes and subchondral cysts on tomosynthesis images when read by radiologists with different levels of expertise. Forty subjects aged >40 years had both knees evaluated using tomosynthesis. Images were read by an "experienced" reader (musculoskeletal radiologist with prior experience) and an "inexperienced" reader (radiology resident with no prior experience). Readers graded osteophytes from 0 to 3 and noted the presence/absence of subchondral cysts in four locations of the tibiofemoral joint. Twenty knees were randomly selected and re-read. Inter- and intrareader reliabilities were calculated using overall exact percent agreement and weighted κ statistics. Diagnostic performance of the two readers was compared against magnetic resonance imaging readings by an expert reader (professor of musculoskeletal radiology). The experienced reader showed substantial intrareader reliability for graded reading of osteophytes (90%, κ=0.93), osteophyte detection (95%, κ=0.86) and cyst detection (95%, κ=0.83). The inexperienced reader showed perfect intrareader reliability for cyst detection (100%, κ=1.00) but intrareader reliability for graded reading (75%, κ=0.79) and detection (80%, κ=0.61) of osteophytes was lower than the experienced reader. Inter-reader reliability was 61% (κ=0.72) for graded osteophyte reading, 91% (κ=0.82) for osteophyte detection, and 88% (κ=0.66) for cyst detection. Diagnostic performance of the experienced reader was higher than the inexperienced reader regarding osteophyte detection (sensitivity range 0.74-0.95 vs. 0.54-0.75 for all locations) but diagnostic performance was similar for subchondral cysts. Tomosynthesis offers excellent intrareader reliability regardless of the reader experience, but experience is important for detection of osteophytes.

Reliability of semiquantitative assessment of osteophytes and subchondral cysts on tomosynthesis images by radiologists with different levels of expertise

PubMed Central

Hayashi, Daichi; Xu, Li; Gusenburg, Jeffrey; Roemer, Frank W.; Hunter, David J.; Li, Ling; Guermazi, Ali

2014-01-01

PURPOSE We aimed to assess reliability of the evaluation of osteophytes and subchondral cysts on tomosynthesis images when read by radiologists with different levels of expertise. MATERIALS AND METHODS Forty subjects aged >40 years had both knees evaluated using tomosynthesis. Images were read by an “experienced” reader (musculoskeletal radiologist with prior experience) and an “inexperienced” reader (radiology resident with no prior experience). Readers graded osteophytes from 0 to 3 and noted the presence/absence of subchondral cysts in four locations of the tibiofemoral joint. Twenty knees were randomly selected and re-read. Inter- and intrareader reliabilities were calculated using overall exact percent agreement and weighted κ statistics. Diagnostic performance of the two readers was compared against magnetic resonance imaging readings by an expert reader (professor of musculoskeletal radiology). RESULTS The experienced reader showed substantial intrareader reliability for graded reading of osteophytes (90%, κ=0.93), osteophyte detection (95%, κ=0.86) and cyst detection (95%, κ=0.83). The inexperienced reader showed perfect intrareader reliability for cyst detection (100%, κ=1.00) but intrareader reliability for graded reading (75%, κ=0.79) and detection (80%, κ=0.61) of osteophytes was lower than the experienced reader. Inter-reader reliability was 61% (κ=0.72) for graded osteophyte reading, 91% (κ=0.82) for osteophyte detection, and 88% (κ=0.66) for cyst detection. Diagnostic performance of the experienced reader was higher than the inexperienced reader regarding osteophyte detection (sensitivity range 0.74–0.95 vs. 0.54–0.75 for all locations) but diagnostic performance was similar for subchondral cysts. CONCLUSION Tomosynthesis offers excellent intrareader reliability regardless of the reader experience, but experience is important for detection of osteophytes. PMID:24834489

Automation in airport security X-ray screening of cabin baggage: Examining benefits and possible implementations of automated explosives detection.

PubMed

Hättenschwiler, Nicole; Sterchi, Yanik; Mendes, Marcia; Schwaninger, Adrian

2018-10-01

Bomb attacks on civil aviation make detecting improvised explosive devices and explosive material in passenger baggage a major concern. In the last few years, explosive detection systems for cabin baggage screening (EDSCB) have become available. Although used by a number of airports, most countries have not yet implemented these systems on a wide scale. We investigated the benefits of EDSCB with two different levels of automation currently being discussed by regulators and airport operators: automation as a diagnostic aid with an on-screen alarm resolution by the airport security officer (screener) or EDSCB with an automated decision by the machine. The two experiments reported here tested and compared both scenarios and a condition without automation as baseline. Participants were screeners at two international airports who differed in both years of work experience and familiarity with automation aids. Results showed that experienced screeners were good at detecting improvised explosive devices even without EDSCB. EDSCB increased only their detection of bare explosives. In contrast, screeners with less experience (tenure < 1 year) benefitted substantially from EDSCB in detecting both improvised explosive devices and bare explosives. A comparison of all three conditions showed that automated decision provided better human-machine detection performance than on-screen alarm resolution and no automation. This came at the cost of slightly higher false alarm rates on the human-machine system level, which would still be acceptable from an operational point of view. Results indicate that a wide-scale implementation of EDSCB would increase the detection of explosives in passenger bags and automated decision instead of automation as diagnostic aid with on screen alarm resolution should be considered. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Irradiation influence on the detection of genetic-modified soybeans

NASA Astrophysics Data System (ADS)

Villavicencio, A. L. C. H.; Araújo, M. M.; Baldasso, J. G.; Aquino, S.; Konietzny, U.; Greiner, R.

2004-09-01

Three soybean varieties were analyzed to evaluate the irradiation influence on the detection of genetic modification. Samples were treated in a 60Co facility at dose levels of 0, 500, 800, and 1000Gy. The seeds were at first analyzed by Comet Assay as a rapid screening irradiation detection method. Secondly, germination test was performed to detect the viability of irradiated soybeans. Finally, because of its high sensitivity, its specificity and rapidity the polimerase chain reaction was the method applied for genetic modified organism detection. The analysis of DNA by the single technique of microgel electrophoresis of single cells (DNA Comet Assay) showed that DNA damage increased with increasing radiation doses. No negative influence of irradiation on the genetic modification detection was found.

Ultrasound detection of cartilage calcification at knee level in calcium pyrophosphate deposition disease.

PubMed

Gutierrez, Marwin; Di Geso, Luca; Salaffi, Fausto; Carotti, Marina; Girolimetti, Rita; De Angelis, Rossella; Filippucci, Emilio; Grassi, Walter

2014-01-01

To determine the sensitivity, specificity, and accuracy of ultrasound (US) in the detection of cartilage calcification at knee level in patients with calcium pyrophosphate deposition disease (CPDD) and to assess the interobserver reliability. Seventy-four CPDD patients and 83 controls with other chronic arthritis were included. All patients underwent a clinical examination, synovial fluid analysis, and radiographic assessment of the knee. US examinations were performed in order to detect hyperechoic spots within the hyaline cartilage layer and hyperechoic areas within the meniscal fibrocartilage. Twenty patients were assessed by 2 operators in order to calculate the interobserver reliability. A total of 314 knees in 157 patients (74 with CPDD, 19 with rheumatoid arthritis, 17 with spondyloarthritis, 32 with osteoarthritis, and 15 with gout) were assessed. In the 74 patients with CPDD, hyaline cartilage spots were detected by US in at least 1 knee in 44 patients (59.5%), whereas radiography detected hyaline cartilage spots in 34 patients (45.9%) (P < 0.001). Meniscal fibrocartilage calcifications were detected by US in 67 of the 74 CPDD patients (90.5%), whereas conventional radiography detected calcifications in 62 patients (83.7%) (P = 0.011). The criterion validity expressed as percentage of sensitivity, specificity, and accuracy of US in the detection of articular cartilage calcification was high. Both kappa values and overall agreement percentages showed moderate to excellent agreement. US is an accurate and reliable imaging technique in the detection of articular cartilage calcification at knee level in patients with CPDD. Copyright © 2014 by the American College of Rheumatology.

Using Peptide-Level Proteomics Data for Detecting Differentially Expressed Proteins.

PubMed

Suomi, Tomi; Corthals, Garry L; Nevalainen, Olli S; Elo, Laura L

2015-11-06

The expression of proteins can be quantified in high-throughput means using different types of mass spectrometers. In recent years, there have emerged label-free methods for determining protein abundance. Although the expression is initially measured at the peptide level, a common approach is to combine the peptide-level measurements into protein-level values before differential expression analysis. However, this simple combination is prone to inconsistencies between peptides and may lose valuable information. To this end, we introduce here a method for detecting differentially expressed proteins by combining peptide-level expression-change statistics. Using controlled spike-in experiments, we show that the approach of averaging peptide-level expression changes yields more accurate lists of differentially expressed proteins than does the conventional protein-level approach. This is particularly true when there are only few replicate samples or the differences between the sample groups are small. The proposed technique is implemented in the Bioconductor package PECA, and it can be downloaded from http://www.bioconductor.org.

Individual differences in conflict detection during reasoning.

PubMed

Frey, Darren; Johnson, Eric D; De Neys, Wim

2018-05-01

Decades of reasoning and decision-making research have established that human judgment is often biased by intuitive heuristics. Recent "error" or bias detection studies have focused on reasoners' abilities to detect whether their heuristic answer conflicts with logical or probabilistic principles. A key open question is whether there are individual differences in this bias detection efficiency. Here we present three studies in which co-registration of different error detection measures (confidence, response time and confidence response time) allowed us to assess bias detection sensitivity at the individual participant level in a range of reasoning tasks. The results indicate that although most individuals show robust bias detection, as indexed by increased latencies and decreased confidence, there is a subgroup of reasoners who consistently fail to do so. We discuss theoretical and practical implications for the field.

Interaction Networks: Generating High Level Hints Based on Network Community Clustering

ERIC Educational Resources Information Center

Eagle, Michael; Johnson, Matthew; Barnes, Tiffany

2012-01-01

We introduce a novel data structure, the Interaction Network, for representing interaction-data from open problem solving environment tutors. We show how using network community detecting techniques are used to identify sub-goals in problems in a logic tutor. We then use those community structures to generate high level hints between sub-goals.…

A robust measure of HIV-1 population turnover within chronically infected individuals.

PubMed

Achaz, G; Palmer, S; Kearney, M; Maldarelli, F; Mellors, J W; Coffin, J M; Wakeley, J

2004-10-01

A simple nonparameteric test for population structure was applied to temporally spaced samples of HIV-1 sequences from the gag-pol region within two chronically infected individuals. The results show that temporal structure can be detected for samples separated by about 22 months or more. The performance of the method, which was originally proposed to detect geographic structure, was tested for temporally spaced samples using neutral coalescent simulations. Simulations showed that the method is robust to variation in samples sizes and mutation rates, to the presence/absence of recombination, and that the power to detect temporal structure is high. By comparing levels of temporal structure in simulations to the levels observed in real data, we estimate the effective intra-individual population size of HIV-1 to be between 10(3) and 10(4) viruses, which is in agreement with some previous estimates. Using this estimate and a simple measure of sequence diversity, we estimate an effective neutral mutation rate of about 5 x 10(-6) per site per generation in the gag-pol region. The definition and interpretation of estimates of such "effective" population parameters are discussed.

Combination of Fluorescent in situ Hybridization (FISH) and Immunofluorescence Imaging for Detection of Cytokine Expression in Microglia/Macrophage Cells

PubMed Central

Fe Lanfranco, Maria; Loane, David J.; Mocchetti, Italo; Burns, Mark P.; Villapol, Sonia

2017-01-01

Microglia and macrophage cells are the primary producers of cytokines in response to neuroinflammatory processes. But these cytokines are also produced by other glial cells, endothelial cells, and neurons. It is essential to identify the cells that produce these cytokines to target their different levels of activation. We used dual RNAscope® fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) techniques to visualize the mRNA expression pattern of pro- and anti-inflammatory cytokines in microglia/macrophages cells. Using these methods, we can associate one mRNA to specific cell types when combining with different cellular markers by immunofluorescence. Results from RNAscope® probes IL-1β, TNFα, TGFβ, IL-10 or Arg1, showed colocalization with antibodies for microglia/macrophage cells. These target probes showed adequate sensitivity and specificity to detect mRNA expression. New FISH detection techniques combined with immunohistochemical techniques will help to jointly determine the protein and mRNA localization, as well as provide reliable quantification of the mRNA expression levels. PMID:29238736

Extinction is not a natural consequence of unilateral spatial neglect: evidence from contrast detection experiments.

PubMed

Pavlovskaya, Marina; Soroker, Nachum; Bonneh, Yoram

2007-06-15

To investigate whether the expression of visual extinction is dependent upon the contralesional low saliency existing in neglect, we tested stroke patients with neglect and extinction, as well as normal controls, on detection of a peripheral Gabor patch, while a competing patch was presented simultaneously on the other side. To compensate for uneven saliency we set the contrast level relative to the detection threshold on each side. Patients showed contralesional extinction even for stimuli set at threshold level. They differed from controls in their sensitivity to changes in relative contrast between sides, showing stronger tendency for extinction and requiring much higher contrast increments in the target patch in order to eliminate extinction. The differences between normal and pathological extinction, shown despite compensation for contralesional perceptual attenuation due to neglect, suggest an additional extinction-specific deficit related to an abnormal interplay between the bilaterally presented stimuli. These findings have important theoretical implications concerning the relationship between neglect and extinction. They demonstrate that the hypothetical 'attentional gradient', taken to explain reduced saliency of stimuli in the neglected side, cannot fully account for the phenomenon of extinction.

Protective immunity and lack of histopathological damage two years after DNA vaccination against infectious hematopoietic necrosis virus in trout

USGS Publications Warehouse

Kurath, Gael; Garver, Kyle A.; Corbeil, Serge; Elliott, Diane G.; Anderson, Eric D.; LaPatra, Scott E.

2006-01-01

The DNA vaccine pIHNw-G encodes the glycoprotein of the fish rhabdovirus infectious hematopoietic necrosis virus (IHNV). Vaccine performance in rainbow trout was measured 3, 6, 13, 24, and 25 months after vaccination. At three months all fish vaccinated with 0.1 μg pIHNw-G had detectable neutralizing antibody (NAb) and they were completely protected from lethal IHNV challenge with a relative percent survival (RPS) of 100% compared to control fish. Viral challenges at 6, 13, 24, and 25 months post-vaccination showed protection with RPS values of 47–69%, while NAb seroprevalence declined to undetectable levels. Passive transfer experiments with sera from fish after two years post-vaccination were inconsistent but significant protection was observed in some cases. The long-term duration of protection observed here defined a third temporal phase in the immune response to IHNV DNA vaccination, characterized by reduced but significant levels of protection, and decline or absence of detectable NAb titers. Examination of multiple tissues showed an absence of detectable long-term histopathological damage due to DNA vaccination.

Imipenem resistance in clinical Escherichia coli from Qom, Iran.

PubMed

Shams, Saeed; Hashemi, Ali; Esmkhani, Mohammad; Kermani, Somaye; Shams, Elham; Piccirillo, Alessandra

2018-05-18

The emergence of metallo-β-lactamase-producing Enterobacteriaceae is a worldwide health concern. In this study, the first evaluation of MBL genes, bla IMP and bla VIM , in Escherichia coli resistant to imipenem isolated from urine and blood specimens in Qom, Iran is described. Three hundred urine and blood specimens were analysed to detect the presence of E. coli. Resistance to imipenem and other antimicrobials was determined by disk diffusion and MIC. MBL production was screened using CDDT. PCR was also carried out to determine the presence of bla IMP and bla VIM genes in imipenem-resistant isolates. In total, 160 E. coli isolates were collected from March to May 2016. According to disk diffusion, high-level of resistance (20%) to cefotaxime was observed, whereas the lowest (1%) was detected for tetracycline. In addition, five isolates showed resistance to imipenem with a MIC ≥ 4 µg/mL. CDDT test confirmed that five isolates were MBL-producing strains, but no bla IMP and bla VIM genes were detected. Results of this study show a very low level of resistance to imipenem in our geographical area.

Detection and quantification of ochratoxin A and deoxynivalenol in barley grains by GC-MS and electronic nose.

PubMed

Olsson, J; Börjesson, T; Lundstedt, T; Schnürer, J

2002-02-05

Mycotoxin contamination of cereal grains can be detected and quantified using complex extraction procedures and analytical techniques. Normally, the grain odour, i.e. the presence of non-grain volatile metabolites, is used for quality classification of grain. We have investigated the possibility of using fungal volatile metabolites as indicators of mycotoxins in grain. Ten barley samples with normal odour, and 30 with some kind of off-odour were selected from Swedish granaries. The samples were evaluated with regard to moisture content, fungal contamination, ergosterol content, and levels of ochratoxin A (OA) and deoxynivalenol (DON). Volatile compounds were also analysed using both an electronic nose and gas chromatography combined with mass spectrometry (GC-MS). Samples with normal odour had no detectable ochratoxin A and average DON contents of 16 microg kg(-1) (range 0-80), while samples with off-odour had average OA contents of 76 microg kg(-1) (range 0-934) and DON contents of 69 microg kg(-1) (range 0-857). Data were evaluated by multivariate data analysis using projection methods such as principal component analysis (PCA) and partial least squares (PLS). The results show that it was possible to classify the OA level as below or above the maximum limit of 5 microg kg(-1) cereal grain established by the Swedish National Food Administration, and that the DON level could be estimated using PLS. Samples with OA levels below 5 microg kg(-1) had higher concentration of aldehydes (nonanal, 2-hexenal) and alcohols (1-penten-3-ol, 1-octanol). Samples with OA levels above 5 microg kg(-1) had higher concentrations of ketones (2-hexanone, 3-octanone). The GC-MS system predicted OA concentrations with a higher accuracy than the electronic nose, since the GC-MS misclassified only 3 of 37 samples and the electronic nose 7 of 37 samples. No correlation was found between odour and OA level, as samples with pronounced or strong off-odours had OA levels both below and above 5 microg kg(-1). We were able to predict DON levels in the naturally contaminated barley samples using the volatile compounds detected and quantified by either GC-MS or the electronic nose. Pentane, methylpyrazine, 3-pentanone, 3-octene-2-ol and isooctylacetate showed a positive correlation with DON, while ethylhexanol, pentadecane, toluene, 1-octanol, 1-nonanol, and 1-heptanol showed a negative correlation with DON. The root mean square error of estimation values for prediction of DON based on GC-MS and electronic nose data were 16 and 25 microg kg(-1), respectively.

Subliminal gaze cues increase preference levels for items in the gaze direction.

PubMed

Mitsuda, Takashi; Masaki, Syuta

2017-08-29

Another individual's gaze automatically shifts an observer's attention to a location. This reflexive response occurs even when the gaze is presented subliminally over a short period. Another's gaze also increases the preference level for items in the gaze direction; however, it was previously unclear if this effect occurs when the gaze is presented subliminally. This study showed that the preference levels for nonsense figures looked at by a subliminal gaze were significantly greater than those for items that were subliminally looked away from (Task 1). Targets that were looked at by a subliminal gaze were detected faster (Task 2); however, the participants were unable to detect the gaze direction (Task 3). These results indicate that another individual's gaze automatically increases the preference levels for items in the gaze direction without conscious awareness.

Right wing authoritarianism is associated with race bias in face detection

PubMed Central

Bret, Amélie; Beffara, Brice; McFadyen, Jessica; Mermillod, Martial

2017-01-01

Racial discrimination can be observed in a wide range of psychological processes, including even the earliest phases of face detection. It remains unclear, however, whether racially-biased low-level face processing is influenced by ideologies, such as right wing authoritarianism or social dominance orientation. In the current study, we hypothesized that socio-political ideologies such as these can substantially predict perceptive racial bias during early perception. To test this hypothesis, 67 participants detected faces within arrays of neutral objects. The faces were either Caucasian (in-group) or North African (out-group) and either had a neutral or angry expression. Results showed that participants with higher self-reported right-wing authoritarianism were more likely to show slower response times for detecting out- vs. in-groups faces. We interpreted our results according to the Dual Process Motivational Model and suggest that socio-political ideologies may foster early racial bias via attentional disengagement. PMID:28692705

Establishment of a simple and quantitative immunospot assay for detecting anti-type II collagen antibody using an infrared fluorescence imaging system (IFIS).

PubMed

Ota, Shusuke; Kanazawa, Satoshi; Kobayashi, Masaaki; Otsuka, Takanobu; Okamoto, Takashi

2005-04-01

Antibodies to type II collagen (col II) have been detected in patients with rheumatoid arthritis and in animal models of collagen induced arthritis. Here, we describe a novel method to detect anti-col II antibodies using an immunospot assay with an infrared fluorescence imaging system. This method showed very high sensitivity and specificity, and was simple, with low background levels. It also showed higher reproducibility and linearity, with a dynamic range of approximately 500-fold, than the conventional immunospot assay with enhanced chemiluminescence detection. Using this method we were able to demonstrate the antibody affinity maturation process in mice immunized with col II. In these immunized mice, although cross-reactive antibodies reacting with other collagen species were detected in earlier stages of immunization, the titers of cross-reactive antibodies rapidly diminished after the antigen boost, concomitantly with the elevation of the anti-col II antibody. The method and its possible applications are discussed.

Elevated urinary level of vitamin D-binding protein as a novel biomarker for diabetic nephropathy

PubMed Central

TIAN, XIAO-QIN; ZHAO, LI-MIN; GE, JIA-PU; ZHANG, YAN; XU, YAN-CHENG

2014-01-01

Improving the early prediction and detection of diabetic nephropathy (DN) remains a great challenge in disease management. The aim of this study was to evaluate the early detection power of urinary vitamin D-binding protein (VDBP) for the diagnosis of DN. Urine samples were obtained from 45 healthy volunteers and 105 diabetic patients with normoalbuminuria (DM group), microalbuminuria (DN1 group) and macroalbuminuria (DN2 group) (n=35 per group). The VDBP expression patterns in urine from patients and controls were quantified by western blot analysis. The excretion levels of urinary VDBP were quantified with enzyme-linked immunosorbent assay. The quantification results were obtained by correcting for creatinine expression and showed that urinary VDBP levels were significantly elevated in the patients of the DN1 and DN2 groups compared with those of the DM group and normal controls (1,011.33±325.30 and 1,406.34±239.66 compared with 466.54±213.63 and 125.48±98.27 ng/mg, respectively) (P<0.001). Receiver operating characteristic analysis of urinary VDBP levels for the diagnosis of DN rendered an optimum cut-off value of 552.243 ng/mg corresponding to 92.86% sensitivity and 85.00% specificity, which also showed an area under the ROC curve of 0.966. In conclusion, the findings of the present study suggest that urinary VDBP may be a potential biomarker for the early detection and prevention of DN. Further studies are required to examine the pathogenic mechanisms of elevated VDBP levels and their role in the diagnosis of DN. PMID:24396416

Groth Deep Locations Image

NASA Image and Video Library

2003-07-25

NASA's Galaxy Evolution Explorer photographed this ultraviolet color blowup of the Groth Deep Image on June 22 and June 23, 2003. Hundreds of galaxies are detected in this portion of the image, and the faint red galaxies are believed to be 6 billion light years away. The white boxes show the location of these distant galaxies, of which more than a 100 can be detected in this image. NASA astronomers expect to detect 10,000 such galaxies after extrapolating to the full image at a deeper exposure level. http://photojournal.jpl.nasa.gov/catalog/PIA04626

A real-time multi-gases detection and concentration measurements based-on time-division multiplexed-lasers

NASA Astrophysics Data System (ADS)

Yazdandoust, Fatemeh; Tatenguem Fankem, Hervé; Milde, Tobias; Jimenez, Alvaro; Sacher, Joachim

2018-02-01

We report the development of a platform, based-on a Field-Programmable Gate Arrays (FPGAs) and suitable for Time-Division-Multiplexed DFB lasers. The designed platform is subsequently combined with a spectroscopy setup, for detection and quantification of species in a gas mixture. The experimental results show a detection limit of 460 ppm, an uncertainty of 0.1% and a computation time of less than 1000 clock cycles. The proposed system offers a high level of flexibility and is applicable to arbitrary types of gas-mixtures.

Object Detection and Classification by Decision-Level Fusion for Intelligent Vehicle Systems.

PubMed

Oh, Sang-Il; Kang, Hang-Bong

2017-01-22

To understand driving environments effectively, it is important to achieve accurate detection and classification of objects detected by sensor-based intelligent vehicle systems, which are significantly important tasks. Object detection is performed for the localization of objects, whereas object classification recognizes object classes from detected object regions. For accurate object detection and classification, fusing multiple sensor information into a key component of the representation and perception processes is necessary. In this paper, we propose a new object-detection and classification method using decision-level fusion. We fuse the classification outputs from independent unary classifiers, such as 3D point clouds and image data using a convolutional neural network (CNN). The unary classifiers for the two sensors are the CNN with five layers, which use more than two pre-trained convolutional layers to consider local to global features as data representation. To represent data using convolutional layers, we apply region of interest (ROI) pooling to the outputs of each layer on the object candidate regions generated using object proposal generation to realize color flattening and semantic grouping for charge-coupled device and Light Detection And Ranging (LiDAR) sensors. We evaluate our proposed method on a KITTI benchmark dataset to detect and classify three object classes: cars, pedestrians and cyclists. The evaluation results show that the proposed method achieves better performance than the previous methods. Our proposed method extracted approximately 500 proposals on a 1226 × 370 image, whereas the original selective search method extracted approximately 10 6 × n proposals. We obtained classification performance with 77.72% mean average precision over the entirety of the classes in the moderate detection level of the KITTI benchmark dataset.

Object Detection and Classification by Decision-Level Fusion for Intelligent Vehicle Systems

PubMed Central

Oh, Sang-Il; Kang, Hang-Bong

2017-01-01

To understand driving environments effectively, it is important to achieve accurate detection and classification of objects detected by sensor-based intelligent vehicle systems, which are significantly important tasks. Object detection is performed for the localization of objects, whereas object classification recognizes object classes from detected object regions. For accurate object detection and classification, fusing multiple sensor information into a key component of the representation and perception processes is necessary. In this paper, we propose a new object-detection and classification method using decision-level fusion. We fuse the classification outputs from independent unary classifiers, such as 3D point clouds and image data using a convolutional neural network (CNN). The unary classifiers for the two sensors are the CNN with five layers, which use more than two pre-trained convolutional layers to consider local to global features as data representation. To represent data using convolutional layers, we apply region of interest (ROI) pooling to the outputs of each layer on the object candidate regions generated using object proposal generation to realize color flattening and semantic grouping for charge-coupled device and Light Detection And Ranging (LiDAR) sensors. We evaluate our proposed method on a KITTI benchmark dataset to detect and classify three object classes: cars, pedestrians and cyclists. The evaluation results show that the proposed method achieves better performance than the previous methods. Our proposed method extracted approximately 500 proposals on a 1226×370 image, whereas the original selective search method extracted approximately 106×n proposals. We obtained classification performance with 77.72% mean average precision over the entirety of the classes in the moderate detection level of the KITTI benchmark dataset. PMID:28117742

Development of a label-free immunosensor system for detecting plasma cortisol levels in fish.

PubMed

Wu, Haiyun; Ohnuki, Hitoshi; Hibi, Kyoko; Ren, Huifeng; Endo, Hideaki

2016-02-01

Fishes display a wide variation in their physiological responses to stress, which is clearly evident in the plasma corticosteroid changes, chiefly cortisol levels in fish. In the present study, we describe a novel label-free immunosensor for detecting plasma cortisol levels. The method is based on immunologic reactions and amperometric measurement using cyclic voltammetry. For the immobilization of the antibody on the surface of sensing electrode, we used a self-assembled monolayer of thiol-containing compounds. Using this electrode, we detect the CV signal change caused by the generation of antigen-antibody complex. The immunosensor showed a response to cortisol levels, and the anodic peak value linearly decreased with a correlation coefficient of 0.990 in diluted plasma. The specificity of the label-free immunosensor system was investigated using other steroid hormones, such as 17α, 20β-dihydroxy-4-pregnen-3-one, progesterone, estriol, estradiol, and testosterone. The specific detection of cortisol was suggested by a minimal change from -0.32 to 0.51 μA in the anodic peak value of the other steroid hormones. The sensor system was used to determine the plasma cortisol levels in Nile tilapia (Oreochromis niloticus), and the results were compared with those of the same samples determined using the conventional method (ELISA). A good correlation was obtained between values determined using both methods (correlation coefficient 0.993). These findings suggest that the proposed label-free immunosensor could be useful for rapid and convenient analysis of cortisol levels in fish plasma samples.

From trees to forest: relational complexity network and workload of air traffic controllers.

PubMed

Zhang, Jingyu; Yang, Jiazhong; Wu, Changxu

2015-01-01

In this paper, we propose a relational complexity (RC) network framework based on RC metric and network theory to model controllers' workload in conflict detection and resolution. We suggest that, at the sector level, air traffic showing a centralised network pattern can provide cognitive benefits in visual search and resolution decision which will in turn result in lower workload. We found that the network centralisation index can account for more variance in predicting perceived workload and task completion time in both a static conflict detection task (Study 1) and a dynamic one (Study 2) in addition to other aircraft-level and pair-level factors. This finding suggests that linear combination of aircraft-level or dyad-level information may not be adequate and the global-pattern-based index is necessary. Theoretical and practical implications of using this framework to improve future workload modelling and management are discussed. We propose a RC network framework to model the workload of air traffic controllers. The effect of network centralisation was examined in both a static conflict detection task and a dynamic one. Network centralisation was predictive of perceived workload and task completion time over and above other control variables.

Diurnal Profiles of Melatonin Synthesis-Related Indoles, Catecholamines and Their Metabolites in the Duck Pineal Organ

PubMed Central

Lewczuk, Bogdan; Ziółkowska, Natalia; Prusik, Magdalena; Przybylska-Gornowicz, Barbara

2014-01-01

This study characterizes the diurnal profiles of ten melatonin synthesis-related indoles, the quantitative relations between these compounds, and daily variations in the contents of catecholamines and their metabolites in the domestic duck pineal organ. Fourteen-week-old birds, which were reared under a 12L:12D cycle, were killed at two-hour intervals. The indole contents were measured using HPLC with fluorescence detection, whereas the levels of catecholamines and their metabolites were measured using HPLC with electrochemical detection. All indole contents, except for tryptophan, showed significant diurnal variations. The 5-hydroxytryptophan level was approximately two-fold higher during the scotophase than during the photophase. The serotonin content increased during the first half of the photophase, remained elevated for approximately 10 h and then rapidly decreased in the middle of the scotophase. N-acetylserotonin showed the most prominent changes, with a more than 15-fold increase at night. The melatonin cycle demonstrated only an approximately 5-fold difference between the peak and nadir. The 5-methoxytryptamine content was markedly elevated during the scotophase. The 5-hydroxyindole acetic acid, 5-hydroxytryptophol, 5-methoxyindole acetic acid and 5-methoxytryptophol profiles were analogous to the serotonin rhythm. The norepinephrine and dopamine contents showed no significant changes. The DOPA, DOPAC and homovanillic acid levels were higher during the scotophase than during the photophase. Vanillylmandelic acid showed the opposite rhythm, with an elevated level during the daytime. PMID:25032843

Automatic detection of articulation disorders in children with cleft lip and palate.

PubMed

Maier, Andreas; Hönig, Florian; Bocklet, Tobias; Nöth, Elmar; Stelzle, Florian; Nkenke, Emeka; Schuster, Maria

2009-11-01

Speech of children with cleft lip and palate (CLP) is sometimes still disordered even after adequate surgical and nonsurgical therapies. Such speech shows complex articulation disorders, which are usually assessed perceptually, consuming time and manpower. Hence, there is a need for an easy to apply and reliable automatic method. To create a reference for an automatic system, speech data of 58 children with CLP were assessed perceptually by experienced speech therapists for characteristic phonetic disorders at the phoneme level. The first part of the article aims to detect such characteristics by a semiautomatic procedure and the second to evaluate a fully automatic, thus simple, procedure. The methods are based on a combination of speech processing algorithms. The semiautomatic method achieves moderate to good agreement (kappa approximately 0.6) for the detection of all phonetic disorders. On a speaker level, significant correlations between the perceptual evaluation and the automatic system of 0.89 are obtained. The fully automatic system yields a correlation on the speaker level of 0.81 to the perceptual evaluation. This correlation is in the range of the inter-rater correlation of the listeners. The automatic speech evaluation is able to detect phonetic disorders at an experts'level without any additional human postprocessing.

Change detection of polarimetric SAR images based on the KummerU Distribution

NASA Astrophysics Data System (ADS)

Chen, Quan; Zou, Pengfei; Li, Zhen; Zhang, Ping

2014-11-01

In the society of PolSAR image segmentation, change detection and classification, the classical Wishart distribution has been used for a long time, but it especially suit to low-resolution SAR image, because in traditional sensors, only a small number of scatterers are present in each resolution cell. With the improving of SAR systems these years, the classical statistical models can therefore be reconsidered for high resolution and polarimetric information contained in the images acquired by these advanced systems. In this study, SAR image segmentation algorithm based on level-set method, added with distance regularized level-set evolution (DRLSE) is performed using Envisat/ASAR single-polarization data and Radarsat-2 polarimetric images, respectively. KummerU heterogeneous clutter model is used in the later to overcome the homogeneous hypothesis at high resolution cell. An enhanced distance regularized level-set evolution (DRLSE-E) is also applied in the later, to ensure accurate computation and stable level-set evolution. Finally, change detection based on four polarimetric Radarsat-2 time series images is carried out at Genhe area of Inner Mongolia Autonomous Region, NorthEastern of China, where a heavy flood disaster occurred during the summer of 2013, result shows the recommend segmentation method can detect the change of watershed effectively.

Melon Resistance to Cucurbit yellow stunting disorder virus Is Characterized by Reduced Virus Accumulation.

PubMed

Marco, Cristina F; Aguilar, Juan M; Abad, Jesús; Gómez-Guillamón, María Luisa; Aranda, Miguel A

2003-07-01

ABSTRACT The pattern of accumulation of Cucurbit yellow stunting disorder virus (CYSDV; genus Crinivirus, family Closteroviridae) RNA has been analyzed in several cucurbit accessions. In susceptible accessions of melon (Cucumis melo), cucumber (Cucumis sativus), marrow (Cucurbita maxima), and squash (Cucurbita pepo), CYSDV RNA accumulation peaked during the first to second week postinoculation in the first to third leaf above the inoculated one; younger leaves showed very low or undetectable levels of CYSDV. Three melon accessions previously shown to remain asymptomatic after CYSDV inoculation under natural conditions were also assayed for their susceptibility to CYSDV. Hybridization and reverse transcription-polymerase chain reaction (RT-PCR) analysis of noninoculated leaves showed that only one of these, C-105, remained virus-free for up to 6 weeks after whitefly inoculation. In this accession, very low CYSDV levels were detected by RT-PCR in whitefly-inoculated leaves, and therefore, multiplication or spread of CYSDV in C-105 plants appeared to remain restricted to the inoculated leaves. When C-105 plants were graft inoculated, CYSDV RNA could be detected in phloem tissues, but the systemic colonization of C-105 by CYSDV upon graft inoculation seemed to be seriously impeded. Additionally, in situ hybridization experiments showed that, after C-105 graft inoculation, only a portion of the vascular bundles in petioles and stems were colonized by CYSDV and virus could not be found in leaf veins. RT-PCR experiments using primers to specifically detect negative-sense CYSDV RNA were carried out and showed that CYSDV replication took place in graft-inoculated C-105 scions. Therefore, the resistance mechanism may involve a restriction of the virus movement in the vascular system of the plants and/or prevention of high levels of virus accumulation.

Deep image mining for diabetic retinopathy screening.

PubMed

Quellec, Gwenolé; Charrière, Katia; Boudi, Yassine; Cochener, Béatrice; Lamard, Mathieu

2017-07-01

Deep learning is quickly becoming the leading methodology for medical image analysis. Given a large medical archive, where each image is associated with a diagnosis, efficient pathology detectors or classifiers can be trained with virtually no expert knowledge about the target pathologies. However, deep learning algorithms, including the popular ConvNets, are black boxes: little is known about the local patterns analyzed by ConvNets to make a decision at the image level. A solution is proposed in this paper to create heatmaps showing which pixels in images play a role in the image-level predictions. In other words, a ConvNet trained for image-level classification can be used to detect lesions as well. A generalization of the backpropagation method is proposed in order to train ConvNets that produce high-quality heatmaps. The proposed solution is applied to diabetic retinopathy (DR) screening in a dataset of almost 90,000 fundus photographs from the 2015 Kaggle Diabetic Retinopathy competition and a private dataset of almost 110,000 photographs (e-ophtha). For the task of detecting referable DR, very good detection performance was achieved: A z =0.954 in Kaggle's dataset and A z =0.949 in e-ophtha. Performance was also evaluated at the image level and at the lesion level in the DiaretDB1 dataset, where four types of lesions are manually segmented: microaneurysms, hemorrhages, exudates and cotton-wool spots. For the task of detecting images containing these four lesion types, the proposed detector, which was trained to detect referable DR, outperforms recent algorithms trained to detect those lesions specifically, with pixel-level supervision. At the lesion level, the proposed detector outperforms heatmap generation algorithms for ConvNets. This detector is part of the Messidor® system for mobile eye pathology screening. Because it does not rely on expert knowledge or manual segmentation for detecting relevant patterns, the proposed solution is a promising image mining tool, which has the potential to discover new biomarkers in images. Copyright © 2017 Elsevier B.V. All rights reserved.

Some signals cannot wait: effects of a national campaign on early detection of cancer among Dutch adults (>55 years).

PubMed

Reubsaet, Astrid; van Osch, Liesbeth A D M; de Vries, Hein; de Coul, Maaike R Op; Lechner, Lilian

2009-10-01

The present study examined the effects of the campaign "early detection of cancer" on knowledge, attitudes, awareness, and intention to perform passive detection and timely seeking medical help. Further, the campaign was evaluated on recall and recognition and the various campaign components were evaluated. A longitudinal study using a Solomon four-group design among 784 Dutch adults aged 55 years and older was conducted. Data was gathered by means of telephone interviews. The results showed moderate levels of campaign awareness. After the campaign, solely respondents who received a pre-test questionnaire and were aware of the campaign had significant higher cancer knowledge levels regarding passive detection. Respondents who were only aware of the campaign were significantly more willing to perform passive detection behavior and to timely seek medical help in the future. Further, they were more aware that paying attention to cancer warning signs can lead to early detection of cancer. It can be concluded that solely the combination of the pre-test questionnaire and exposure to the campaign had a significant positive impact on respondents' cancer knowledge levels. The effects of the campaign on intention and awareness are indistinct and could be a consequence of (the results of) a self-selection bias. It seems that the dose, frequency, and duration of the campaign should be increased in order to substantiate the effects of the campaign.

Use of CHAID Decision Trees to Formulate Pathways for the Early Detection of Metabolic Syndrome in Young Adults

PubMed Central

Liu, Pei-Yang

2014-01-01

Metabolic syndrome (MetS) in young adults (age 20–39) is often undiagnosed. A simple screening tool using a surrogate measure might be invaluable in the early detection of MetS. Methods. A chi-squared automatic interaction detection (CHAID) decision tree analysis with waist circumference user-specified as the first level was used to detect MetS in young adults using data from the National Health and Nutrition Examination Survey (NHANES) 2009-2010 Cohort as a representative sample of the United States population (n = 745). Results. Twenty percent of the sample met the National Cholesterol Education Program Adult Treatment Panel III (NCEP) classification criteria for MetS. The user-specified CHAID model was compared to both CHAID model with no user-specified first level and logistic regression based model. This analysis identified waist circumference as a strong predictor in the MetS diagnosis. The accuracy of the final model with waist circumference user-specified as the first level was 92.3% with its ability to detect MetS at 71.8% which outperformed comparison models. Conclusions. Preliminary findings suggest that young adults at risk for MetS could be identified for further followup based on their waist circumference. Decision tree methods show promise for the development of a preliminary detection algorithm for MetS. PMID:24817904

Gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of Japanese encephalitis virus

NASA Astrophysics Data System (ADS)

Huang, Su-Hua; Yang, Tsuey-Ching; Tsai, Ming-Hong; Tsai, I.-Shou; Lu, Huang-Chih; Chuang, Pei-Hsin; Wan, Lei; Lin, Ying-Ju; Lai, Chih-Ho; Lin, Cheng-Wen

2008-10-01

Virus isolation and antibody detection are routinely used for diagnosis of Japanese encephalitis virus (JEV) infection, but the low level of transient viremia in some JE patients makes JEV isolation from clinical and surveillance samples very difficult. We describe the use of gold nanoparticle-based RT-PCR and real-time quantitative RT-PCR assays for detection of JEV from its RNA genome. We tested the effect of gold nanoparticles on four different PCR systems, including conventional PCR, reverse-transcription PCR (RT-PCR), and SYBR green real-time PCR and RT-PCR assays for diagnosis in the acute phase of JEV infection. Gold nanoparticles increased the amplification yield of the PCR product and shortened the PCR time compared to the conventional reaction. In addition, nanogold-based real-time RT-PCR showed a linear relationship between Ct and template amount using ten-fold dilutions of JEV. The nanogold-based RT-PCR and real-time quantitative RT-PCR assays were able to detect low levels (1-10 000 copies) of the JEV RNA genomes extracted from culture medium or whole blood, providing early diagnostic tools for the detection of low-level viremia in the acute-phase infection. The assays described here were simple, sensitive, and rapid approaches for detection and quantitation of JEV in tissue cultured samples as well as clinical samples.

Laser photoacoustic spectroscopy helps fight terrorism: High sensitivity detection of chemical Warfare Agent and explosives

NASA Astrophysics Data System (ADS)

Patel, C. K. N.

2008-01-01

Tunable laser photoacoustic spectroscopy is maturing rapidly in its applications to real world problems. One of the burning problems of the current turbulent times is the threat of terrorist acts against civilian population. This threat appears in two distinct forms. The first is the potential release of chemical warfare agents (CWA), such as the nerve agents, in a crowded environment. An example of this is the release of Sarin by Aum Shinrikyo sect in a crowded Tokyo subway in 1995. An example of the second terrorist threat is the ever-present possible suicide bomber in crowded environment such as airports, markets and large buildings. Minimizing the impact of both of these threats requires early detection of the presence of the CWAs and explosives. Photoacoustic spectroscopy is an exquisitely sensitive technique for the detection of trace gaseous species, a property that Pranalytica has extensively exploited in its CO2 laser based commercial instrumentation for the sub-ppb level detection of a number of industrially important gases including ammonia, ethylene, acrolein, sulfur hexafluoride, phosphine, arsine, boron trichloride and boron trifluoride. In this presentation, I will focus, however, on our recent use of broadly tunable single frequency high power room temperature quantum cascade lasers (QCL) for the detection of the CWAs and explosives. Using external grating cavity geometry, we have developed room temperature QCLs that produce continuously tunable single frequency CW power output in excess of 300 mW at wavelengths covering 5 μm to 12 μm. I will present data that show a CWA detection capability at ppb levels with false alarm rates below 1:108. I will also show the capability of detecting a variety of explosives at a ppb level, again with very low false alarm rates. Among the explosives, we have demonstrated the capability of detecting homemade explosives such as triacetone triperoxide and its liquid precursor, acetone which is a common household liquid. This capability, deployed at airports and other public places, will go a long way towards increasing public safety and minimizing inconveniences faced in airline travel.

Predictive Detection of Tuberculosis using Electronic Nose Technology

NASA Astrophysics Data System (ADS)

Gibson, Tim; Kolk, Arend; Reither, Klaus; Kuipers, Sjoukje; Hallam, Viv; Chandler, Rob; Dutta, Ritaban; Maboko, Leonard; Jung, Jutta; Klatser, Paul

2009-05-01

The adaptation and use of a Bloodhound® ST214 electronic nose to rapidly detect TB in sputum samples has been discussed in the past, with some promising results being obtained in 2007. Some of the specific VOC's associated with Mycobacteria tuberculosis organisms are now being discovered and a paper was published in 2008, but the method of predicting the presence of TB in sputum samples using the VOC biomarkers has yet to be fully optimised. Nevertheless, with emphasis on the sampling techniques and with new data processing techniques to obtain consistent results progress is being made Sensitivity and specificity levels for field detection of TB have been set by WHO at a minimum level of 85% and 95% respectively, and the e-nose technique is working towards these figures. In a series of experiments carried out in Mbeya, Tanzania, Africa, data from a full 5 days of sampling was combined giving a total of 248 sputum samples analysed. From the data obtained we can report results that show specificities and sensitivities in the 70-80% region when actually predicting the presence of TB in unknown sputum samples. The results are a further step forward in the rapid detection of TB in the clinics in developing countries and show continued promise for future development of an optimised instrument for TB prediction.

Water level and strain changes preceding and following the August 4, 1985 Kettleman Hills, California, earthquake

USGS Publications Warehouse

Roeloffs, E.; Quilty, E.

1997-01-01

Two of the four wells monitored near Parkfield, California, during 1985 showed water level rises beginning three days before the M4 6.1 Kettleman Hills earthquake. In one of these wells, the 3.0 cm rise was nearly unique in five years of water level data. However, in the other well, which showed a 3.8 cm rise, many other changes of comparable size have been observed. Both wells that did not display pre-earthquake rises tap partially confined aquifers that cannot sustain pressure changes due to tectonic strain having periods longer than several days. We evaluate the effect of partial aquifer confinement on the ability of these four wells to display water level changes in response to aquifer strain. Although the vertical hydraulic diffusivities cannot be determined uniquely, we can find a value of diffusivity for each site that is consistent with the site's tidal and barometric responses as well as with the rate of partial recovery of the coseismic water level drops. Furthermore, the diffusivity for one well is high enough to explain why the preseismic rise could not have been detected there. For the fourth well, the diffusivity is high enough to have reduced the size of the preseismic signal as much as 50%, although it should still have been detectable. Imperfect confinement cannot explain the persistent water level changes in the two partially confined aquifers, but it does show that they were not due to volume strain. The pre-earthquake water level rises may have been precursors to the Kettleman Hills earthquake. If so, they probably were not caused by accelerating slip over the part of the fault plane that ruptured in that earthquake because they are of opposite sign to the observed coseismic water level drops.

Direct Detection and Identification of Prosthetic Joint Infection Pathogens in Synovial Fluid by Metagenomic Shotgun Sequencing.

PubMed

Ivy, Morgan I; Thoendel, Matthew J; Jeraldo, Patricio R; Greenwood-Quaintance, Kerryl E; Hanssen, Arlen D; Abdel, Matthew P; Chia, Nicholas; Yao, Janet Z; Tande, Aaron J; Mandrekar, Jayawant N; Patel, Robin

2018-05-30

Background: Metagenomic shotgun sequencing has the potential to transform how serious infections are diagnosed by offering universal, culture-free pathogen detection. This may be especially advantageous for microbial diagnosis of prosthetic joint infection (PJI) by synovial fluid analysis, since synovial fluid cultures are not universally positive, and synovial fluid is easily obtained pre-operatively. We applied a metagenomics-based approach to synovial fluid in an attempt to detect microorganisms in 168 failed total knee arthroplasties. Results: Genus- and species-level analysis of metagenomic sequencing yielded the known pathogen in 74 (90%) and 68 (83%) of the 82 culture-positive PJIs analyzed, respectively, with testing of two (2%) and three (4%) samples, respectively, yielding additional pathogens not detected by culture. For the 25 culture-negative PJIs tested, genus- and species-level analysis yielded 19 (76%) and 21 (84%) samples with insignificant findings, respectively, and 6 (24%) and 4 (16%) with potential pathogens detected, respectively. Genus- and species-level analysis of the 60 culture-negative aseptic failure cases yielded 53 (88.3%) and 56 (93.3%) cases with insignificant findings, and 7 (11.7%) and 4 (6.7%) with potential clinically-significant organisms detected, respectively. There was one case of aseptic failure with synovial fluid culture growth; metagenomic analysis showed insignificant findings, suggesting possible synovial fluid culture contamination. Conclusion: Metagenomic shotgun sequencing can detect pathogens involved in PJI when applied to synovial fluid and may be particularly useful for culture-negative cases. Copyright © 2018 American Society for Microbiology.

Evaluating detection and estimation capabilities of magnetometer-based vehicle sensors

NASA Astrophysics Data System (ADS)

Slater, David M.; Jacyna, Garry M.

2013-05-01

In an effort to secure the northern and southern United States borders, MITRE has been tasked with developing Modeling and Simulation (M&S) tools that accurately capture the mapping between algorithm-level Measures of Performance (MOP) and system-level Measures of Effectiveness (MOE) for current/future surveillance systems deployed by the the Customs and Border Protection Office of Technology Innovations and Acquisitions (OTIA). This analysis is part of a larger M&S undertaking. The focus is on two MOPs for magnetometer-based Unattended Ground Sensors (UGS). UGS are placed near roads to detect passing vehicles and estimate properties of the vehicle's trajectory such as bearing and speed. The first MOP considered is the probability of detection. We derive probabilities of detection for a network of sensors over an arbitrary number of observation periods and explore how the probability of detection changes when multiple sensors are employed. The performance of UGS is also evaluated based on the level of variance in the estimation of trajectory parameters. We derive the Cramer-Rao bounds for the variances of the estimated parameters in two cases: when no a priori information is known and when the parameters are assumed to be Gaussian with known variances. Sample results show that UGS perform significantly better in the latter case.

Salient object detection based on multi-scale contrast.

PubMed

Wang, Hai; Dai, Lei; Cai, Yingfeng; Sun, Xiaoqiang; Chen, Long

2018-05-01

Due to the development of deep learning networks, a salient object detection based on deep learning networks, which are used to extract the features, has made a great breakthrough compared to the traditional methods. At present, the salient object detection mainly relies on very deep convolutional network, which is used to extract the features. In deep learning networks, an dramatic increase of network depth may cause more training errors instead. In this paper, we use the residual network to increase network depth and to mitigate the errors caused by depth increase simultaneously. Inspired by image simplification, we use color and texture features to obtain simplified image with multiple scales by means of region assimilation on the basis of super-pixels in order to reduce the complexity of images and to improve the accuracy of salient target detection. We refine the feature on pixel level by the multi-scale feature correction method to avoid the feature error when the image is simplified at the above-mentioned region level. The final full connection layer not only integrates features of multi-scale and multi-level but also works as classifier of salient targets. The experimental results show that proposed model achieves better results than other salient object detection models based on original deep learning networks. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dual Mode NOx Sensor: Measuring Both the Accumulated Amount and Instantaneous Level at Low Concentrations

PubMed Central

Groß, Andrea; Beulertz, Gregor; Marr, Isabella; Kubinski, David J.; Visser, Jaco H.; Moos, Ralf

2012-01-01

The accumulating-type (or integrating-type) NOx sensor principle offers two operation modes to measure low levels of NOx: The direct signal gives the total amount dosed over a time interval and its derivative the instantaneous concentration. With a linear sensor response, no baseline drift, and both response times and recovery times in the range of the gas exchange time of the test bench (5 to 7 s), the integrating sensor is well suited to reliably detect low levels of NOx. Experimental results are presented demonstrating the sensor’s integrating properties for the total amount detection and its sensitivity to both NO and to NO2. We also show the correlation between the derivative of the sensor signal and the known gas concentration. The long-term detection of NOx in the sub-ppm range (e.g., for air quality measurements) is discussed. Additionally, a self-adaption of the measurement range taking advantage of the temperature dependency of the sensitivity is addressed. PMID:22736980

Performance evaluation of canny edge detection on a tiled multicore architecture

NASA Astrophysics Data System (ADS)

Brethorst, Andrew Z.; Desai, Nehal; Enright, Douglas P.; Scrofano, Ronald

2011-01-01

In the last few years, a variety of multicore architectures have been used to parallelize image processing applications. In this paper, we focus on assessing the parallel speed-ups of different Canny edge detection parallelization strategies on the Tile64, a tiled multicore architecture developed by the Tilera Corporation. Included in these strategies are different ways Canny edge detection can be parallelized, as well as differences in data management. The two parallelization strategies examined were loop-level parallelism and domain decomposition. Loop-level parallelism is achieved through the use of OpenMP,1 and it is capable of parallelization across the range of values over which a loop iterates. Domain decomposition is the process of breaking down an image into subimages, where each subimage is processed independently, in parallel. The results of the two strategies show that for the same number of threads, programmer implemented, domain decomposition exhibits higher speed-ups than the compiler managed, loop-level parallelism implemented with OpenMP.

Biomarkers of Plasmodium falciparum Infection during Pregnancy in Women Living in Northeastern Tanzania

PubMed Central

Boström, Stéphanie; Ibitokou, Samad; Oesterholt, Mayke; Schmiegelow, Christentze; Persson, Jan-Olov; Minja, Daniel; Lusingu, John; Lemnge, Martha; Fievet, Nadine; Deloron, Philippe; Luty, Adrian J. F.; Troye-Blomberg, Marita

2012-01-01

In pregnant women, Plasmodium falciparum infections are an important cause of maternal morbidity as well as fetal and neonatal mortality. Erythrocytes infected by these malaria-causing parasites accumulate through adhesive interactions in placental intervillous spaces, thus evading detection in peripheral blood smears. Sequestered infected erythrocytes induce inflammation, offering the possibility of detecting inflammatory mediators in peripheral blood that could act as biomarkers of placental infection. In a longitudinal, prospective study in Tanzania, we quantified a range of different cytokines, chemokines and angiogenic factors in peripheral plasma samples, taken on multiple sequential occasions during pregnancy up to and including delivery, from P. falciparum-infected women and matched uninfected controls. The results show that during healthy, uninfected pregnancies the levels of most of the panel of molecules we measured were largely unchanged except at delivery. In women with P. falciparum, however, both comparative and longitudinal assessments consistently showed that the levels of IL-10 and IP-10 increased significantly whilst that of RANTES decreased significantly, regardless of gestational age at the time the infection was detected. ROC curve analysis indicated that a combination of increased IL-10 and IP-10 levels and decreased RANTES levels might be predictive of P. falciparum infections. In conclusion, our data suggest that host biomarkers in peripheral blood may represent useful diagnostic markers of P. falciparum infection during pregnancy, but placental histology results would need to be included to verify these findings. PMID:23155405

Ripeness detection simulation of oil palm fruit bunches using laser-based imaging system

NASA Astrophysics Data System (ADS)

Shiddiq, Minarni; Fitmawati, Anjasmara, Ridho; Sari, Nurmaya; Hefniati

2017-01-01

Ripeness is one of important factors for quality sorting of harvested oil palm fresh fruit bunches (FFB). Traditional ripeness classifications using FFB color and number of fruit loose for harvesting have some disadvantages especially for high oil palm trees. A laser based imaging system is proposed to substitute the traditional method. In this study, ripeness detection simulation of oil palm FFBs was performed. The system composed of two diode lasers with 532 nm and 680 nm in wavelengths and a CMOS camera which was set on a rotating plate for easy adjustment of laser beam hitting FFB. The FFB samples were placed on an aluminum platform with 4 height variations, 1.5 m, 2 m, 2.5 m, and 3 m. The relations of reflectance intensities represented by Red Green Blue (RGB) values of the FFB images to the height variations and ripeness levels of FFBs with and without laser beam were analyzed. The samples were from Tenera variety with 4 ripeness levels called F0, F1, F3, and F4. The results showed that the red component of RGB values were dominant for FFBs without laser and with red laser. The average RGB values are higher for F3 (ripe) level and F4 (overripe). Imaging with green laser showed consistency. Imaging methods using laser was able to differentiate ripeness levels of oil palm fresh fruit bunch, it could be applied for future remote detection of oil palm FFB ripeness.

Differential response in foliar chemistry of three ash species to emerald ash borer adult feeding.

PubMed

Chen, Yigen; Whitehill, Justin G A; Bonello, Pierluigi; Poland, Therese M

2011-01-01

The emerald ash borer (EAB; Agrilus planipennis Fairmaire; Coleoptera: Buprestidae), is an exotic wood-boring beetle that has been threatening North American ash (Fraxinus spp.) resources since its discovery in Michigan and Ontario in 2002. In this study, we investigated the phytochemical responses of the three most common North American ash species (black, green, and white ash) in northeastern USA to EAB adult feeding. Black ash was the least responsive to EAB adult feeding in terms of the induction of volatile compounds, and levels of only two (indole and benzyl cyanide) of the 11 compounds studied increased. In green ash, levels of two [(E)-β-ocimene and indole] of the 11 volatile compounds studied were elevated, while the levels of two green leaf volatiles [hexanal and (E)-2-hexenal] decreased. White ash showed the greatest response with an increase in levels of seven of the 11 compounds studied. Qualitative differences among ash species were detected. Among the phenolic compounds detected, ligustroside was the only one detected in all three species. Oleuropein aglycone and 2 unidentified compounds were found only in black ash; coumaroylquinic acid and feruloylquinic acid were detected only in green ash; and verbascoside hexoside was detected only in white ash. EAB adult feeding did not elicit or decrease concentrations of any selected individual phenolic compounds. However, although levels of total phenolics from black and green ash foliage were not affected by EAB adult feeding, they decreased significantly in white ash. EAB adult feeding elevated chymotrypsin inhibitors in black ash. The possible ecological implications of these findings are discussed.

[Copeptin and ischemia modified albumin in early diagnosis and prognosis of myocardial damage in acute organic phosphorus pesticide poisoning].

PubMed

Li, Jing; Zhang, Jianjun; Li, Na; Li, Jia; Liu, Juan; Liu, Qian

2015-03-01

To assess the value of combined detection of copeptin and ischemia modified albumin (IMA) in early diagnosis and prognostic evaluation of myocardial damage in patients with acute organic phosphorus pesticide poisoning (AOPP). A total of 126 AOPP patients were examined for blood copepin and IMA levels and myocardial injury markers within 1 h after admission. Copeptin and IMA levels significantly increased in patients with AOPP compared with those in the control subjects. Copeptin and IMA levels were significantly higher in severe AOPP cases than in mild to moderate cases (P<0.05). Logistic regression analysis showed that increased copeptin and IMA levels and severe complications of AOPP were associated with an increased risk of cardiovascular events. Early detection of copeptin and IMA levels has important clinical value in early diagnosis and prognostic evaluation of myocardial damage in patients with AOPP, and their levels are positively correlated with the severity of the condition.

Concorde noise-induced building vibrations John F. Kennedy International Airport

NASA Technical Reports Server (NTRS)

Mayes, W. H.; Deloach, R.; Stephens, D. G.; Cawthorn, J. M.; Holmes, H. K.; Lewis, R. B.; Holliday, B. G.; Ward, D. W.

1978-01-01

The outdoor and indoor noise levels resulting from aircraft flyovers and certain nonaircraft events were recorded at six home sites along with the associated vibration levels in the walls, windows, and floors of these test homes. Limited subjective tests conducted to examine the human detection and annoyance thresholds for building vibration and rattle caused by aircraft noise showed that both vibration and rattle were detected subjectively in several houses for some operations of both the Concorde and subsonic aircraft. Preliminary results indicate that the relationship between window vibration and aircraft noise is: (1) linear, with vibration levels being accurately predicted from OASPL levels measured near the window; (2) consistent from flyover to flyover for a given aircraft type under approach conditions; (3) no different for Concorde than for other conventional jet transports (in the case of window vibrations induced under approach power conditions); and (4) relatively high levels of window vibration measured during Concorde operations are due more to higher OASPL levels than to unique Concorde source characteristics.

Nutrients, suspended sediment, and pesticides in waters of the Red River of the North Basin, Minnesota, North Dakota, and South Dakota, 1970-90

USGS Publications Warehouse

Tornes, L.H.; Brigham, M.E.

1994-01-01

A relatively large fraction of stream samples had detectable quantities of 2,4-D, a- and y-HCH, and atrazine. These samples covered time spans of as much as 15 years and were from sites downstream from large drainage basins; however, concentrations were well below US EPA MCLs. One county-level study showed higher 2,4-D concentrations at upstream sites than at the outlet from a small basin. This indicates that downstream sites may fail to show impaired water-quality and the fate of pesticides used in the basin. Following the 1972 ban on DDT, concentrations of DDT in fish samples from the Red River of the North quickly decreased. Fish concentrations of DDE and DDD decreased more slowly. Low levels of DDE and DDD were detected in fish 14 years after the DDT ban.

Using Forensic Psychology to Teach Basic Psychological Processes: Eyewitness Memory and Lie Detection

ERIC Educational Resources Information Center

Costanzo, Mark A.

2013-01-01

Teachers can incorporate topics in forensic psychology into lower level courses to increase student interest and to show how psychological processes influence outcomes in high-stakes applied contexts. One such topic is eyewitness identification, which teachers can use to show how stress affects memory and how memories can become distorted during…

Detecting transit signatures of exoplanetary rings using SOAP3.0

NASA Astrophysics Data System (ADS)

Akinsanmi, B.; Oshagh, M.; Santos, N. C.; Barros, S. C. C.

2018-01-01

Context. It is theoretically possible for rings to have formed around extrasolar planets in a similar way to that in which they formed around the giant planets in our solar system. However, no such rings have been detected to date. Aims: We aim to test the possibility of detecting rings around exoplanets by investigating the photometric and spectroscopic ring signatures in high-precision transit signals. Methods: The photometric and spectroscopic transit signals of a ringed planet is expected to show deviations from that of a spherical planet. We used these deviations to quantify the detectability of rings. We present SOAP3.0 which is a numerical tool to simulate ringed planet transits and measure ring detectability based on amplitudes of the residuals between the ringed planet signal and best fit ringless model. Results: We find that it is possible to detect the photometric and spectroscopic signature of near edge-on rings especially around planets with high impact parameter. Time resolution ≤7 min is required for the photometric detection, while 15 min is sufficient for the spectroscopic detection. We also show that future instruments like CHEOPS and ESPRESSO, with precisions that allow ring signatures to be well above their noise-level, present good prospects for detecting rings.

A Novel Method to Detect Early Colorectal Cancer Based on Chromosome Copy Number Variation in Plasma.

PubMed

Xu, Jun-Feng; Kang, Qian; Ma, Xing-Yong; Pan, Yuan-Ming; Yang, Lang; Jin, Peng; Wang, Xin; Li, Chen-Guang; Chen, Xiao-Chen; Wu, Chao; Jiao, Shao-Zhuo; Sheng, Jian-Qiu

2018-01-01

Colonoscopy screening has been accepted broadly to evaluate the risk and incidence of colorectal cancer (CRC) during health examination in outpatients. However, the intrusiveness, complexity and discomfort of colonoscopy may limit its application and the compliance of patients. Thus, more reliable and convenient diagnostic methods are necessary for CRC screening. Genome instability, especially copy-number variation (CNV), is a hallmark of cancer and has been proved to have potential in clinical application. We determined the diagnostic potential of chromosomal CNV at the arm level by whole-genome sequencing of CRC plasma samples (n = 32) and healthy controls (n = 38). Arm level CNV was determined and the consistence of arm-level CNV between plasma and tissue was further analyzed. Two methods including regular z score and trained Support Vector Machine (SVM) classifier were applied for detection of colorectal cancer. In plasma samples of CRC patients, the most frequent deletions were detected on chromosomes 6, 8p, 14q and 1p, and the most frequent amplifications occurred on chromosome 19, 5, 2, 9p and 20p. These arm-level alterations detected in plasma were also observed in tumor tissues. We showed that the specificity of regular z score analysis for the detection of colorectal cancer was 86.8% (33/38), whereas its sensitivity was only 56.3% (18/32). Applying a trained SVM classifier (n = 40 in trained group) as the standard to detect colorectal cancer relevance ratio in the test samples (n = 30), a sensitivity of 91.7% (11/12) and a specificity 88.9% (16/18) were finally reached. Furthermore, all five early CRC patients in stages I and II were successfully detected. Trained SVM classifier based on arm-level CNVs can be used as a promising method to screen early-stage CRC. © 2018 The Author(s). Published by S. Karger AG, Basel.

Combined branched-DNA and conventional HBV PCR assays for detection of serum HBV-DNA in hepatitis B e antigen-positive chronic hepatitis B patients.

PubMed

Ozdarendeli, Aykut; Toroman, Zulal Asci; Bulut, Yasemin; Demirbag, Kutbeddin; Kalkan, Ahmet; Ozden, Mehmet; Kilic, Suleyman Sirri

2006-01-01

Monitoring of HBV replication level is very useful for the management of patients with chronic HBV. However, the use of the correct tools to quantify HBV-DNA levels in serum and monitor the replication of HBV is of paramount importance in terms of diagnosis, and antiviral treatment of patients with chronic HBV infection. The aim of this study was to combine the bDNA assay and HBV PCR to improve detection of viremia the patients with HBeAg-positive chronic hepatitis B infection. In this study, 67 HBeAg-positive chronic hepatitis B patients were analyzed to determine viremia level using bDNA and HBV PCR assays. Sixty-four patients with HBeAg-positive chronic hepatitis B showed positivity by conventional HBV PCR, whereas 56 subjects with HBeAg-positive chronic hepatitis B showed HBV-DNA levels by bDNA. The results indicated that it is reasonable to use the bDNA assay to determine HBV replicative activity first, and use conventional HBV-PCR for HBeAg-positive chronic hepatitis B patient samples that are negative in bDNA assay.

Diurnal variation in bacterioplankton composition and DNA damage in the microbial community from an Andean oligotrophic lake.

PubMed

Fernández-Zenoff, María V; Estévez, María C; Farías, María E

2014-01-01

Laguna Azul is an oligotrophic lake situated at 4,560 m above sea level and subject to a high level of solar radiation. Bacterioplankton community composition (BCC) was analysed by denaturing gradient gel electrophoresis and the impact of solar ultraviolet radiation was assessed by measuring cyclobutane pyrimidine dimers (CPD). Furthermore, pure cultures of Acinetobacter johnsonii A2 and Rhodococcus sp. A5 were exposed simultaneously and CPD accumulation was studied. Gel analyses generated a total of 7 sequences belonging to Alpha-proteobacteria (1 band), Beta-proteobacteria (1 band), Bacteroidetes (2 bands), Actinobacteria (1 band), and Firmicutes (1 band). DGGE profiles showed minimal changes in BCC and no CPD was detected even though a high level of damage was found in biodosimeters. A. johnsonii A2 showed low level of DNA damage while Rhodococcus sp. A5 exhibited high resistance since no CPD were detected under natural UV-B exposure, suggesting that the bacterial community is well adapted to this highly solar irradiated environment. Copyright © 2014 Asociación Argentina de Microbiología. Publicado por Elsevier España. All rights reserved.

The effect of ambient cadmium air pollution on the hair mineral content of children.

PubMed

Stewart-Pinkham, S M

1989-01-01

Hair analyses of 80 children with learning and behavioral problems were assessed by age, sex, season, place of residence, exposure to passive smoke and excess contact with known cadmium air pollutant sources. All children had been exposed for at least 2 years to air pollution from a refuse-derived fuel incineration plant. All of the patients had increased hair cadmium compared with a control group, but there was a strong seasonal influence on hair cadmium. Exposure to cadmium was ubiquitous. A neurobehavioral toxic effect was found in children who showed evidence of inhibition of pyrimidine-5'-nucleotidase by low hair phosphorus levels and low zinc levels in whom there was enhanced lead absorption. Hair analyses appear to be a useful biological monitor for detecting toxic effects from ambient air cadmium levels in subsets of the population at risk for heavy metal toxicity. Air filter measurements appear worthless for detecting environmental contamination with cadmium in air with low levels of lead. Trees, on the other hand, which are more adversely affected by cadmium than other heavy metals, show evidence of inhibition of pyrimidine-5'-nucleosidase by excess seeding.

The color of sea level: Importance of spatial variations in spectral shape for assessing the significance of trends

NASA Astrophysics Data System (ADS)

Hughes, Chris W.; Williams, Simon D. P.

2010-10-01

We investigate spatial variations in the shape of the spectrum of sea level variability based on a homogeneously sampled 12 year gridded altimeter data set. We present a method of plotting spectral information as color, focusing on periods between 2 and 24 weeks, which shows that significant spatial variations in the spectral shape exist and contain useful dynamical information. Using the Bayesian Information Criterion, we determine that, typically, a fifth-order autoregressive model is needed to capture the structure in the spectrum. Using this model, we show that statistical errors in fitted local trends range between less than 1 and more than 5 times of what would be calculated assuming "white" noise and that the time needed to detect a 1 mm/yr trend ranges between about 5 years and many decades. For global mean sea level, the statistical error reduces to 0.1 mm/yr over 12 years, with only 2 years needed to detect a 1 mm/yr trend. We find significant regional differences in trend from the global mean. The patterns of these regional differences are indicative of a sea level trend dominated by dynamical ocean processes over this period.

Development of an enzyme-linked immunosorbent assay for detection of cellular and in vivo LRRK2 S935 phosphorylation

PubMed Central

Delbroek, Lore; Van Kolen, Kristof; Steegmans, Liesbeth; da Cunha, Raquel; Mandemakers, Wim; Daneels, Guy; De Bock, Pieter-Jan; Zhang, Jinwei; Gevaert, Kris; De Strooper, Bart; Alessi, Dario R.; Verstreken, Patrik; Moechars, Diederik W.

2014-01-01

After the discovery of kinase activating mutations in leucine-rich repeat kinase 2 (LRRK2) as associated with autosomal dominant forms of Parkinson’s disease, inhibition of the kinase is being extensively explored as a disease modifying strategy. As signaling properties and substrate(s) of LRRK2 are poorly documented, autophosphorylation has been an important readout for the enzyme’s activity. Western blotting using anti-phospho-S910 or S935 LRRK2 antibodies showed effectiveness in demonstrating inhibitory effects of compounds. In this communication we describe two types of enzyme-linked immunosorbent assays (ELISA) to determine LRRK2 protein levels and kinase activity. Both assays take advantage of the sensitivity of the earlier described total and pS935 antibodies for detection (Nichols et al., Biochem. J. 2010) [10]. The first assay is based on anti-GFP-based capturing of overexpressed LRRK2 and is highly suitable to show cellular effects of kinase inhibitors in a 96-well format. In the other platform anti-LRRK2-based capturing allows detection of endogenously expressed LRRK2 in rat tissue with no significant signal in tissue from LRRK2 knockout rats. Furthermore, both assays showed a significant reduction in pS935 levels on cellular and transgenic R1441C/G LRRK2. With the anti-LRRK2 ELISA we were able to detect LRRK2 phosphorylation in human peripheral blood mononuclear cells (PBMC). To conclude, we report two sensitive assays to monitor LRRK2 expression and kinase activity in samples coming from cellular and in vivo experimental settings. Both can show their value in drug screening and biomarker development but will also be useful in the elucidation of LRRK2-mediated signaling pathways. PMID:23313773

Development of Smartphone based Optical Device

NASA Astrophysics Data System (ADS)

Jung, Youngkee

Due to the economy of scale, smartphones are becoming more affordable while their computing powers are increasing dramatically every year. Here we propose a ubiquitous and portable instrument for analyte quantitation by utilizing the characteristics of typical smartphone imaging system and specific design of transducers for different applications. Three testbeds included in this work are: quantitative colorimetric analysis, ultra-low radiant flux detection, and portable spectrometer. As a proof-of-principle for each device, 3-D printed cradle and theoretical simulation with MATLAB have been implemented. First example utilizes the native CMOS camera with their respective RGB channel data and perform an analyte quantitation for typical lateral flow devices (LFD). Histogram analysis method has been employed to detect the analyte concentration and calibration results show good correlation between perceived color change and analyte concentration. The second example shows the possibility of using a conventional CMOS camera for pico Watt level photon flux detection. Since most of consumer grade CMOS cameras cannot detect this level of light intensity and their dark current are relatively higher, a new algorithm called NREA (Noise Reduction by Ensemble Averaging) algorithm was developed to effectively reduce the noise level and increase the SNR (signal to noise ratio). This technique is effective for bioanalytical assays that has lower flux intensity such as fluorescence and luminescence. As a proof-of-principle, we tested the device with Pseudomonas fluorescens M3A and achieved a limit of detection of high 10? CFU/ml. In addition to basic schematic of detection model, another experiment with a silicon photomultiplier (SiPM) has been studied for more sensitive light detectability. Based on both the laser experiment and tw bioluminescent experiments, named Pseudomonas fluorescens M3A and NanoLuc, we found that the miniSM based device has a superior ability than the smartphone to detect the low light intensity. Finally, smartphone based spectrometers have been developed and experiments have been performed to demonstrate its availability. Smartphone spectrometers were designed with two kinds of spectrometer functions, absorbance and reflection spectrometer. Based on the diffraction theory, the experimental results were compared with simulation results and demonstrated the feasibility as a spectrometer. Peak locations were calibrated with diode lasers in three wavelengths (405 nm, 532 nm and 635 nm) and specific software application was developed to capture a spectrum. A Biuret test was done to test its feasibility as an absorbance spectrometer. To show the possibility as a reflection spectrometer, the real meat test was done using a standard experimental process of meat freshness analysis.

Detection of silver nanoparticles in seawater at ppb levels using UV-visible spectrophotometry with long path cells.

PubMed

Lodeiro, Pablo; Achterberg, Eric P; El-Shahawi, Mohammad S

2017-03-01

Silver nanoparticles (AgNPs) are emerging contaminants that are difficult to detect in natural waters. UV-visible spectrophotometry is a simple technique that allows detection of AgNPs through analysis of their characteristic surface plasmon resonance band. The detection limit for nanoparticles using up to 10cm path length cuvettes with UV-visible spectrophotometry is in the 0.1-10ppm range. This detection limit is insufficiently low to observe AgNPs in natural environments. Here we show how the use of capillary cells with an optical path length up to 200cm, forms an excellent technique for rapid detection and quantification of non-aggregated AgNPs at ppb concentrations in complex natural matrices such as seawater. Copyright © 2016 Elsevier B.V. All rights reserved.

Image processing based detection of lung cancer on CT scan images

NASA Astrophysics Data System (ADS)

Abdillah, Bariqi; Bustamam, Alhadi; Sarwinda, Devvi

2017-10-01

In this paper, we implement and analyze the image processing method for detection of lung cancer. Image processing techniques are widely used in several medical problems for picture enhancement in the detection phase to support the early medical treatment. In this research we proposed a detection method of lung cancer based on image segmentation. Image segmentation is one of intermediate level in image processing. Marker control watershed and region growing approach are used to segment of CT scan image. Detection phases are followed by image enhancement using Gabor filter, image segmentation, and features extraction. From the experimental results, we found the effectiveness of our approach. The results show that the best approach for main features detection is watershed with masking method which has high accuracy and robust.

Total oxidant status, total antioxidant capacity and ischemia modified albumin levels in children with celiac disease.

PubMed

Sayar, Ersin; Özdem, Sebahat; Uzun, Gülbahar; İşlek, Ali; Yılmaz, Aygen; Artan, Reha

2015-01-01

In our study, we aimed to investigate ischemia modified albumin (IMA) as an oxidative stress marker, as well as other oxidant and antioxidant markers that have not been evaluated in children with celiac disease. A total of 37 pediatric patients who were diagnosed with celiac disease (CD) and 29 healthy children were enrolled in this prospective study. We evaluated the IMA, total oxidant status, total antioxidant capacity, sulfhydryl, and advanced oxidation protein products in all of the subjects. We also compared the levels at the time of the diagnosis, and following a gluten-free diet (GFD) in the children with CD. While the IMA and the other oxidant marker levels were significantly higher in the patient group compared to the control group, the antioxidant marker levels were found to be significantly lower in the patient group, compared to the control group. We also determined that the tissue transglutaminase IgA showed a highly positive correlation, and that the IMA showed a moderately positive correlation with the Marsh-Oberhuber histopathological stage. Additionally, the IMA and other oxidant marker levels were significantly lower, while the antioxidant marker levels were significantly higher after the GFD, compared to the pre-diet period. We detected that oxidative stress played a role in the pathogenesis of CD, and that this could be evaluated using oxidative stress markers, which would regress after the GFD. We also detected that IMA is a marker that shows a correlation with the histopathological stage, and may be used in the diagnosis.

GMO detection using a bioluminescent real time reporter (BART) of loop mediated isothermal amplification (LAMP) suitable for field use.

PubMed

Kiddle, Guy; Hardinge, Patrick; Buttigieg, Neil; Gandelman, Olga; Pereira, Clint; McElgunn, Cathal J; Rizzoli, Manuela; Jackson, Rebecca; Appleton, Nigel; Moore, Cathy; Tisi, Laurence C; Murray, James A H

2012-04-30

There is an increasing need for quantitative technologies suitable for molecular detection in a variety of settings for applications including food traceability and monitoring of genetically modified (GM) crops and their products through the food processing chain. Conventional molecular diagnostics utilising real-time polymerase chain reaction (RT-PCR) and fluorescence-based determination of amplification require temperature cycling and relatively complex optics. In contrast, isothermal amplification coupled to a bioluminescent output produced in real-time (BART) occurs at a constant temperature and only requires a simple light detection and integration device. Loop mediated isothermal amplification (LAMP) shows robustness to sample-derived inhibitors. Here we show the applicability of coupled LAMP and BART reactions (LAMP-BART) for determination of genetically modified (GM) maize target DNA at low levels of contamination (0.1-5.0% GM) using certified reference material, and compare this to RT-PCR. Results show that conventional DNA extraction methods developed for PCR may not be optimal for LAMP-BART quantification. Additionally, we demonstrate that LAMP is more tolerant to plant sample-derived inhibitors, and show this can be exploited to develop rapid extraction techniques suitable for simple field-based qualitative tests for GM status determination. We also assess the effect of total DNA assay load on LAMP-BART quantitation. LAMP-BART is an effective and sensitive technique for GM detection with significant potential for quantification even at low levels of contamination and in samples derived from crops such as maize with a large genome size. The resilience of LAMP-BART to acidic polysaccharides makes it well suited to rapid sample preparation techniques and hence to both high throughput laboratory settings and to portable GM detection applications. The impact of the plant sample matrix and genome loading within a reaction must be controlled to ensure quantification at low target concentrations.

The alteration of mRNA expression of SOD and GPX genes, and proteins in tomato (Lycopersicon esculentum Mill) under stress of NaCl and/or ZnO nanoparticles.

PubMed

Alharby, Hesham F; Metwali, Ehab M R; Fuller, Michael P; Aldhebiani, Amal Y

2016-11-01

Five cultivars of tomato having different levels of salt stress tolerance were exposed to different treatments of NaCl (0, 3 and 6 g L -1 ) and ZnO-NPs (0, 15 and 30 mg L -1 ). Treatments with NaCl at both 3 and 6 g L -1 suppressed the mRNA levels of superoxide dismutase (SOD) and glutathione peroxidase (GPX) genes in all cultivars while plants treated with ZnO-NPs in the presence of NaCl, showed increments in the mRNA expression levels. This indicated that ZnO-NPs had a positive response on plant metabolism under salt stress. Superior expression levels of mRNA were observed in the salt tolerant cultivars, Sandpoint and Edkawy while the lowest level was detected in the salt sensitive cultivar, Anna Aasa. SDS-PAGE showed clear differences in patterns of protein expression among the cultivars. A negative protein marker for salt sensitivity and ZnO-NPs was detected in cv. Anna Aasa at a molecular weight of 19.162 kDa, while the tolerant cultivar Edkawy had two positive markers at molecular weights of 74.991 and 79.735 kDa.

Privacy preservation and authentication on secure geographical routing in VANET

NASA Astrophysics Data System (ADS)

Punitha, A.; Manickam, J. Martin Leo

2017-05-01

Vehicular Ad hoc Networks (VANETs) play an important role in vehicle-to-vehicle communication as it offers a high level of safety and convenience to drivers. In order to increase the level of security and safety in VANETs, in this paper, we propose a Privacy Preservation and Authentication on Secure Geographical Routing Protocol (PPASGR) for VANET. It provides security by detecting and preventing malicious nodes through two directional antennas such as forward (f-antenna) and backward (b-antenna). The malicious nodes are detected by direction detection, consistency detection and conflict detection. The location of the trusted neighbour is identified using TNT-based location verification scheme after the implementation of the Vehicle Tamper Proof Device (VTPD), Trusted Authority (TA) is generated that produces the anonymous credentials. Finally, VTPD generates pseudo-identity using TA which retrieves the real identity of the sender. Through this approach, the authentication, integrity and confidentiality for routing packets can be achieved. The simulation results show that the proposed approach reduces the packet drop due to attack and improves the packet delivery ratio.

Determination of Domoic Acid in Plankton Net Samples from Golden Horn Estuary, Turkey, Using HPLC with Fluorescence Detection.

PubMed

Dursun, Fuat; Ünlü, Selma; Yurdun, Türkan

2018-03-01

This study focused on the fluctuations of domoic acid (DA) levels in plankton net samples collected from the Golden Horn Estuary (GHE), Turkey, between August 2011 and July 2012. DA concentrations were determined by high-performance liquid chromatography (HPLC), using a fluorenylmethoxycarbonyl (FMOC) derivatization technique. Monthly and biweekly data were evaluated with environmental variables, and their influence on DA production is discussed. DA levels in plankton net samples varied between 0.36 and 94.34 µg L - 1 . DA levels showed remarkable seasonal variation and they were generally higher in May, 2012, but no DA was detected between February and April, 2012. DA production was mostly controlled by temperature, with nitrate and silicate limitations being secondary factors that influenced DA concentrations.

The Applicability of TaqMan-Based Quantitative Real-Time PCR Assays for Detecting and Enumerating Cryptosporidium spp. Oocysts in the Environment

PubMed Central

Staggs, Sarah E.; Beckman, Erin M.; Keely, Scott P.; Mackwan, Reena; Ware, Michael W.; Moyer, Alan P.; Ferretti, James A.; Sayed, Abu; Xiao, Lihua; Villegas, Eric N.

2013-01-01

Quantitative real-time polymerase chain reaction (qPCR) assays to detect Cryptosporidium oocysts in clinical samples are increasingly being used to diagnose human cryptosporidiosis, but a parallel approach for detecting and identifying Cryptosporidium oocyst contamination in surface water sources has yet to be established for current drinking water quality monitoring practices. It has been proposed that Cryptosporidium qPCR-based assays could be used as viable alternatives to current microscopic-based detection methods to quantify levels of oocysts in drinking water sources; however, data on specificity, analytical sensitivity, and the ability to accurately quantify low levels of oocysts are limited. The purpose of this study was to provide a comprehensive evaluation of TaqMan-based qPCR assays, which were developed for either clinical or environmental investigations, for detecting Cryptosporidium oocyst contamination in water. Ten different qPCR assays, six previously published and four developed in this study were analyzed for specificity and analytical sensitivity. Specificity varied between all ten assays, and in one particular assay, which targeted the Cryptosporidium 18S rRNA gene, successfully detected all Cryptosporidium spp. tested, but also cross-amplified T. gondii, fungi, algae, and dinoflagellates. When evaluating the analytical sensitivity of these qPCR assays, results showed that eight of the assays could reliably detect ten flow-sorted oocysts in reagent water or environmental matrix. This study revealed that while a qPCR-based detection assay can be useful for detecting and differentiating different Cryptosporidium species in environmental samples, it cannot accurately measure low levels of oocysts that are typically found in drinking water sources. PMID:23805235

Detecting reciprocity at a global scale

PubMed Central

Frank, Morgan R.; Obradovich, Nick; Sun, Lijun; Woon, Wei Lee; LeVeck, Brad L.; Rahwan, Iyad

2018-01-01

Reciprocity stabilizes cooperation from the level of microbes all the way up to humans interacting in small groups, but does reciprocity also underlie stable cooperation between larger human agglomerations, such as nation states? Famously, evolutionary models show that reciprocity could emerge as a widespread strategy for achieving international cooperation. However, existing studies have only detected reciprocity-driven cooperation in a small number of country pairs. We apply a new method for detecting mutual influence in dynamical systems to a new large-scale data set that records state interactions with high temporal resolution. Doing so, we detect reciprocity between many country pairs in the international system and find that these reciprocating country pairs exhibit qualitatively different cooperative dynamics when compared to nonreciprocating pairs. Consistent with evolutionary theories of cooperation, reciprocating country pairs exhibit higher levels of stable cooperation and are more likely to punish instances of noncooperation. However, countries in reciprocity-based relationships are also quicker to forgive single acts of noncooperation by eventually returning to previous levels of mutual cooperation. By contrast, nonreciprocating pairs are more likely to exploit each other’s cooperation via higher rates of defection. Together, these findings provide the strongest evidence to date that reciprocity is a widespread mechanism for achieving international cooperation. PMID:29326983

Detecting reciprocity at a global scale.

PubMed

Frank, Morgan R; Obradovich, Nick; Sun, Lijun; Woon, Wei Lee; LeVeck, Brad L; Rahwan, Iyad

2018-01-01

Reciprocity stabilizes cooperation from the level of microbes all the way up to humans interacting in small groups, but does reciprocity also underlie stable cooperation between larger human agglomerations, such as nation states? Famously, evolutionary models show that reciprocity could emerge as a widespread strategy for achieving international cooperation. However, existing studies have only detected reciprocity-driven cooperation in a small number of country pairs. We apply a new method for detecting mutual influence in dynamical systems to a new large-scale data set that records state interactions with high temporal resolution. Doing so, we detect reciprocity between many country pairs in the international system and find that these reciprocating country pairs exhibit qualitatively different cooperative dynamics when compared to nonreciprocating pairs. Consistent with evolutionary theories of cooperation, reciprocating country pairs exhibit higher levels of stable cooperation and are more likely to punish instances of noncooperation. However, countries in reciprocity-based relationships are also quicker to forgive single acts of noncooperation by eventually returning to previous levels of mutual cooperation. By contrast, nonreciprocating pairs are more likely to exploit each other's cooperation via higher rates of defection. Together, these findings provide the strongest evidence to date that reciprocity is a widespread mechanism for achieving international cooperation.

Fighting detection using interaction energy force

NASA Astrophysics Data System (ADS)

Wateosot, Chonthisa; Suvonvorn, Nikom

2017-02-01

Fighting detection is an important issue in security aimed to prevent criminal or undesirable events in public places. Many researches on computer vision techniques have studied to detect the specific event in crowded scenes. In this paper we focus on fighting detection using social-based Interaction Energy Force (IEF). The method uses low level features without object extraction and tracking. The interaction force is modeled using the magnitude and direction of optical flows. A fighting factor is developed under this model to detect fighting events using thresholding method. An energy map of interaction force is also presented to identify the corresponding events. The evaluation is performed using NUSHGA and BEHAVE datasets. The results show the efficiency with high accuracy regardless of various conditions.

Detecting text in natural scenes with multi-level MSER and SWT

NASA Astrophysics Data System (ADS)

Lu, Tongwei; Liu, Renjun

2018-04-01

The detection of the characters in the natural scene is susceptible to factors such as complex background, variable viewing angle and diverse forms of language, which leads to poor detection results. Aiming at these problems, a new text detection method was proposed, which consisted of two main stages, candidate region extraction and text region detection. At first stage, the method used multiple scale transformations of original image and multiple thresholds of maximally stable extremal regions (MSER) to detect the text regions which could detect character regions comprehensively. At second stage, obtained SWT maps by using the stroke width transform (SWT) algorithm to compute the candidate regions, then using cascaded classifiers to propose non-text regions. The proposed method was evaluated on the standard benchmark datasets of ICDAR2011 and the datasets that we made our own data sets. The experiment results showed that the proposed method have greatly improved that compared to other text detection methods.

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.

Carrier detection in Duchenne muscular dystrophy. Evidence from a study of obligatory carriers and mothers of isolated cases.

PubMed Central

Sibert, J R; Harper, P S; Thompson, R J; Newcombe, R G

1979-01-01

The mean levels of serum creatinine phosphokinase (CPK) were studied in three groups of women: normal controls (57), obligate carriers for Duchenne muscular dystrophy (30), and mothers of isolated cases of this disease (35). The distribution of the levels in these groups was significantly different and was in keeping with the hypothesis that one-third of isolated cases result from new mutations. The control and carrier ranges overlapped considerably, with the level of CPK of 33% of obligate carriers coming within the 97 1/2 centile of the normal range. Odds against an individual being a carrier were derived for specific mean values of CPK. They should be considered with genetic information using Bayes's theorem. The mean CPK levels in obligate carriers showed significant familial clustering. This may have implications in carrier detection. PMID:485196

Hypoglycemia incidence and risk factors assessment in hospitalized neonates.

PubMed

Zhou, Wei; Yu, Jun; Wu, Yiqi; Zhang, Huawei

2015-03-01

To assess the incidence and risk factors of hypoglycemia in hospitalized neonates in China. Blood glucose level in hospitalized neonates was monitored routinely. Also, in high-risk newborns and neonates with abnormal blood glucose levels in initial detection, the blood sugar level was monitored daily until it was back to normal and stable. Hypoglycemia was detected in 113 out of 668 hospitalized neonates, and the incidence of hypoglycemia was 16.9%. The statistical analysis also showed that hypoglycemia always occurred within one week after birth, especially within three days after birth. Neonates with premature birth, low birth weight and perinatal asphyxia were susceptible to hypoglycemia. Active and continuous monitoring of blood glucose level should be performed in the early newborns, especially in high-risk children, and attention should be paid to timely feeding for the early diagnosis and treatment of neonatal hypoglycemia to reduce its impact on the newborns.

Detection of highly toxic elements (lead and chromium) in commercially available eyeliner (kohl) using laser induced break down spectroscopy

NASA Astrophysics Data System (ADS)

Gondal, M. A.; Dastageer, M. A.; Al-Adel, F. F.; Naqvi, A. A.; Habibullah, Y. B.

2015-12-01

A sensitive laser induced breakdown spectroscopic system was developed and optimized for using it as a sensor for the detection of trace levels of lead and chromium present in the cosmetic eyeliner (kohl) of different price ranges (brands) available in the local market. Kohl is widely used in developing countries for babies as well adults for beautification as well eyes protection. The atomic transition lines at 405.7 nm and 425.4 nm were used as the marker lines for the detection of lead and chromium respectively. The detection system was optimized by finding the appropriate gate delay between the laser excitation and the data acquisition system and also by achieving optically thin plasma near the target by establishing the local thermodynamic equilibrium condition. The detection system was calibrated for these two hazardous elements and the kohl samples under investigation showed 8-15 ppm by mass of lead and 4-9 ppm by mass of Chromium, which are higher than the safe permissible levels of these elements. The limits of detection of the LIBS system for lead and chromium were found to be 1 and 2 ppm respectively.

A Knowledge-Based Approach to Automatic Detection of Equipment Alarm Sounds in a Neonatal Intensive Care Unit Environment.

PubMed

Raboshchuk, Ganna; Nadeu, Climent; Jancovic, Peter; Lilja, Alex Peiro; Kokuer, Munevver; Munoz Mahamud, Blanca; Riverola De Veciana, Ana

2018-01-01

A large number of alarm sounds triggered by biomedical equipment occur frequently in the noisy environment of a neonatal intensive care unit (NICU) and play a key role in providing healthcare. In this paper, our work on the development of an automatic system for detection of acoustic alarms in that difficult environment is presented. Such automatic detection system is needed for the investigation of how a preterm infant reacts to auditory stimuli of the NICU environment and for an improved real-time patient monitoring. The approach presented in this paper consists of using the available knowledge about each alarm class in the design of the detection system. The information about the frequency structure is used in the feature extraction stage, and the time structure knowledge is incorporated at the post-processing stage. Several alternative methods are compared for feature extraction, modeling, and post-processing. The detection performance is evaluated with real data recorded in the NICU of the hospital, and by using both frame-level and period-level metrics. The experimental results show that the inclusion of both spectral and temporal information allows to improve the baseline detection performance by more than 60%.

Presentation Attack Detection for Iris Recognition System Using NIR Camera Sensor

PubMed Central

Nguyen, Dat Tien; Baek, Na Rae; Pham, Tuyen Danh; Park, Kang Ryoung

2018-01-01

Among biometric recognition systems such as fingerprint, finger-vein, or face, the iris recognition system has proven to be effective for achieving a high recognition accuracy and security level. However, several recent studies have indicated that an iris recognition system can be fooled by using presentation attack images that are recaptured using high-quality printed images or by contact lenses with printed iris patterns. As a result, this potential threat can reduce the security level of an iris recognition system. In this study, we propose a new presentation attack detection (PAD) method for an iris recognition system (iPAD) using a near infrared light (NIR) camera image. To detect presentation attack images, we first localized the iris region of the input iris image using circular edge detection (CED). Based on the result of iris localization, we extracted the image features using deep learning-based and handcrafted-based methods. The input iris images were then classified into real and presentation attack categories using support vector machines (SVM). Through extensive experiments with two public datasets, we show that our proposed method effectively solves the iris recognition presentation attack detection problem and produces detection accuracy superior to previous studies. PMID:29695113

Presentation Attack Detection for Iris Recognition System Using NIR Camera Sensor.

PubMed

Nguyen, Dat Tien; Baek, Na Rae; Pham, Tuyen Danh; Park, Kang Ryoung

2018-04-24

Among biometric recognition systems such as fingerprint, finger-vein, or face, the iris recognition system has proven to be effective for achieving a high recognition accuracy and security level. However, several recent studies have indicated that an iris recognition system can be fooled by using presentation attack images that are recaptured using high-quality printed images or by contact lenses with printed iris patterns. As a result, this potential threat can reduce the security level of an iris recognition system. In this study, we propose a new presentation attack detection (PAD) method for an iris recognition system (iPAD) using a near infrared light (NIR) camera image. To detect presentation attack images, we first localized the iris region of the input iris image using circular edge detection (CED). Based on the result of iris localization, we extracted the image features using deep learning-based and handcrafted-based methods. The input iris images were then classified into real and presentation attack categories using support vector machines (SVM). Through extensive experiments with two public datasets, we show that our proposed method effectively solves the iris recognition presentation attack detection problem and produces detection accuracy superior to previous studies.

A Knowledge-Based Approach to Automatic Detection of Equipment Alarm Sounds in a Neonatal Intensive Care Unit Environment

PubMed Central

Nadeu, Climent; Jančovič, Peter; Lilja, Alex Peiró; Köküer, Münevver; Muñoz Mahamud, Blanca; Riverola De Veciana, Ana

2018-01-01

A large number of alarm sounds triggered by biomedical equipment occur frequently in the noisy environment of a neonatal intensive care unit (NICU) and play a key role in providing healthcare. In this paper, our work on the development of an automatic system for detection of acoustic alarms in that difficult environment is presented. Such automatic detection system is needed for the investigation of how a preterm infant reacts to auditory stimuli of the NICU environment and for an improved real-time patient monitoring. The approach presented in this paper consists of using the available knowledge about each alarm class in the design of the detection system. The information about the frequency structure is used in the feature extraction stage, and the time structure knowledge is incorporated at the post-processing stage. Several alternative methods are compared for feature extraction, modeling, and post-processing. The detection performance is evaluated with real data recorded in the NICU of the hospital, and by using both frame-level and period-level metrics. The experimental results show that the inclusion of both spectral and temporal information allows to improve the baseline detection performance by more than 60%. PMID:29404227

What you fear will appear: detection of schematic spiders in spider fear.

PubMed

Peira, Nathalie; Golkar, Armita; Larsson, Maria; Wiens, Stefan

2010-01-01

Various experimental tasks suggest that fear guides attention. However, because these tasks often lack ecological validity, it is unclear to what extent results from these tasks can be generalized to real-life situations. In change detection tasks, a brief interruption of the visual input (i.e., a blank interval or a scene cut) often results in undetected changes in the scene. This setup resembles real-life viewing behavior and is used here to increase ecological validity of the attentional task without compromising control over the stimuli presented. Spider-fearful and nonfearful women detected schematic spiders and flowers that were added to one of two identical background pictures that alternated with a brief blank in between them (i.e., flicker paradigm). Results showed that spider-fearful women detected spiders (but not flowers) faster than did nonfearful women. Because spiders and flowers had similar low-level features, these findings suggest that fear guides attention on the basis of object features rather than simple low-level features.

RUBIC identifies driver genes by detecting recurrent DNA copy number breaks

PubMed Central

van Dyk, Ewald; Hoogstraat, Marlous; ten Hoeve, Jelle; Reinders, Marcel J. T.; Wessels, Lodewyk F. A.

2016-01-01

The frequent recurrence of copy number aberrations across tumour samples is a reliable hallmark of certain cancer driver genes. However, state-of-the-art algorithms for detecting recurrent aberrations fail to detect several known drivers. In this study, we propose RUBIC, an approach that detects recurrent copy number breaks, rather than recurrently amplified or deleted regions. This change of perspective allows for a simplified approach as recursive peak splitting procedures and repeated re-estimation of the background model are avoided. Furthermore, we control the false discovery rate on the level of called regions, rather than at the probe level, as in competing algorithms. We benchmark RUBIC against GISTIC2 (a state-of-the-art approach) and RAIG (a recently proposed approach) on simulated copy number data and on three SNP6 and NGS copy number data sets from TCGA. We show that RUBIC calls more focal recurrent regions and identifies a much larger fraction of known cancer genes. PMID:27396759

Built-Up Area Detection from High-Resolution Satellite Images Using Multi-Scale Wavelet Transform and Local Spatial Statistics

NASA Astrophysics Data System (ADS)

Chen, Y.; Zhang, Y.; Gao, J.; Yuan, Y.; Lv, Z.

2018-04-01

Recently, built-up area detection from high-resolution satellite images (HRSI) has attracted increasing attention because HRSI can provide more detailed object information. In this paper, multi-resolution wavelet transform and local spatial autocorrelation statistic are introduced to model the spatial patterns of built-up areas. First, the input image is decomposed into high- and low-frequency subbands by wavelet transform at three levels. Then the high-frequency detail information in three directions (horizontal, vertical and diagonal) are extracted followed by a maximization operation to integrate the information in all directions. Afterward, a cross-scale operation is implemented to fuse different levels of information. Finally, local spatial autocorrelation statistic is introduced to enhance the saliency of built-up features and an adaptive threshold algorithm is used to achieve the detection of built-up areas. Experiments are conducted on ZY-3 and Quickbird panchromatic satellite images, and the results show that the proposed method is very effective for built-up area detection.

Aircraft Fault Detection and Classification Using Multi-Level Immune Learning Detection

NASA Technical Reports Server (NTRS)

Wong, Derek; Poll, Scott; KrishnaKumar, Kalmanje

2005-01-01

This work is an extension of a recently developed software tool called MILD (Multi-level Immune Learning Detection), which implements a negative selection algorithm for anomaly and fault detection that is inspired by the human immune system. The immunity-based approach can detect a broad spectrum of known and unforeseen faults. We extend MILD by applying a neural network classifier to identify the pattern of fault detectors that are activated during fault detection. Consequently, MILD now performs fault detection and identification of the system under investigation. This paper describes the application of MILD to detect and classify faults of a generic transport aircraft augmented with an intelligent flight controller. The intelligent control architecture is designed to accommodate faults without the need to explicitly identify them. Adding knowledge about the existence and type of a fault will improve the handling qualities of a degraded aircraft and impact tactical and strategic maneuvering decisions. In addition, providing fault information to the pilot is important for maintaining situational awareness so that he can avoid performing an action that might lead to unexpected behavior - e.g., an action that exceeds the remaining control authority of the damaged aircraft. We discuss the detection and classification results of simulated failures of the aircraft's control system and show that MILD is effective at determining the problem with low false alarm and misclassification rates.

A case of hyperammonemia with obstructive urinary tract infection by urease-producing bacteria.

PubMed

Goda, Toshiaki; Watanabe, Kotaro; Kobayashi, Junya; Nagai, Yasuharu; Ohara, Nobuyuki; Takahashi, Daisuke

2017-03-28

A 79-year-old woman was admitted emergently for disturbance of consciousness. Her consciousness level was Japan coma scale 20, and she presented with hypermyotonia. Brain magnetic resonance imaging and cerebrospinal fluid examination showed normal findings. Her blood tests showed an increased ammonia level of 291 μg/dl with normal liver function. We catheterized the bladder for urinary retention. Eight hours after admission, the blood level of ammonia decreased to 57 μg/dl and the patient's consciousness level improved. Corynebacterium pseudodiphtheriticum, which is a bacteria producing urease, was detected from a urine culture. It is important to recognize that obstructive urinary tract infection caused by urease-producing bacteria can cause hyperammonemia.

Ecological risk assessment of heavy metals and polycyclic aromatic hydrocarbons in sediments of rivers Niger and Benue confluence, Lokoja, Central Nigeria.

PubMed

Ekere, Nwachukwu; Yakubu, Newman; Ihedioha, Janefrances

2017-08-01

The concentrations of six heavy metals (HMs) and 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) in sediment samples of the confluence of rivers Niger and Benue were investigated. The ecological risk assessment of the contaminants was carried out. The results showed that the sediment samples were heavily polluted with iron and moderately polluted with Cd while other metals posed no pollution problem when compared with USEPA sediment quality guidelines. Only six out of the 16 priority PAHs were detected in the samples, and source apportionment of the PAHs indicated that they are of pyrogenic origin. The ∑PAHs in the samples were lower than many of similar studies and were of no pollution risk. The ecological risk assessment result of the heavy metals showed that the sediments were of considerable risk due majorly to Cd levels. The HM concentration results statistically showed significant difference between seasons at probability value (P < .05). Data analysis by PCA classified the metals into three different components according to sources. The levels of HMS and PAHs detected in the sediments were correlated for source identification, and the correlation showed that the majority of the pollutants were mainly from anthropogenic sources. There is increasing level of anthropogenic activities at the vicinity of the confluence due to urbanization which may call for periodic monitoring of the sediment quality.

Susceptibility of Clostridium perfringens strains from broiler chickens to antibiotics and anticoccidials.

PubMed

Martel, A; Devriese, L A; Cauwerts, K; De Gussem, K; Decostere, A; Haesebrouck, F

2004-02-01

Clostridium perfringens strains isolated in 2002 from the intestines of broiler chickens from 31 different farms located in Belgium were tested for susceptibility to 12 antibiotics used for therapy, growth promotion or prevention of coccidiosis. All strains were uniformly sensitive to the ionophore antibiotics monensin, lasalocid, salinomycin, maduramycin and narasin. All were sensitive to avilamycin, tylosin and amoxicillin, while flavomycin (bambermycin) showed low or no activity. Chlortetracycline and oxytetracycline were active at very low concentrations, but low-level acquired resistance was detected in 66% of the strains investigated. Fifty percent of these strains carried the tetP(B) resistance gene, while the tet(Q) gene was detected in only one strain. One strain with high-level resistance against tetracyclines carried the tet(M) gene. Sixty-three percent of the strains showed low-level resistance to lincomycin. The lnu(A) and lnu(B) genes were each only found in one strain. Compared with a similar investigation carried out in 1980, an increase was seen in resistance percentages with lincomycin (63% against 49%) and a slight decrease with tetracycline (66% against 74%).

Estimations of BCR-ABL/ABL transcripts by quantitative PCR in chronic myeloid leukaemia after allogeneic bone marrow transplantation and donor lymphocyte infusion.

PubMed

Otazú, Ivone B; Tavares, Rita de Cassia B; Hassan, Rocío; Zalcberg, Ilana; Tabak, Daniel G; Seuánez, Héctor N

2002-02-01

Serial assays of qualitative (multiplex and nested) and quantitative PCR were carried out for detecting and estimating the level of BCR-ABL transcripts in 39 CML patients following bone marrow transplantation. Seven of these patients, who received donor lymphocyte infusions (DLIs) following to relapse, were also monitored. Quantitative estimates of BCR-ABL transcripts were obtained by co-amplification with a competitor sequence. Estimates of ABL transcripts were used, an internal control and the ratio BCR-ABL/ABL was thus estimated for evaluating the kinetics of residual clones. Twenty four patients were followed shortly after BMT; two of these patients were in cytogenetic relapse coexisting with very high BCR-ABL levels while other 22 were in clinical, haematologic and cytogenetic remission 2-42 months after BMT. In this latter group, seven patients showed a favourable clinical-haematological progression in association with molecular remission while in 14 patients quantitative PCR assays indicated molecular relapse that was not associated with an early cytogenetic-haematologic relapse. BCR-ABL/ABL levels could not be correlated with presence of GVHD in 24 patients after BMT. In all seven patients treated with DLI, high levels of transcripts were detected at least 4 months before the appearance of clinical haematological relapse. Following DLI, five of these patients showed decreasing transcript levels from 2 to 5 logs between 4 and 12 months. In eight other patients studied long after BMT, five showed molecular relapse up to 117 months post-BMT and only one showed cytogenetic relapse. Our findings indicated that quantitative estimates of BCR-ABL transcripts were valuable for monitoring minimal residual disease in each patient.

High-sensitivity explosives detection using dual-excitation-wavelength resonance-Raman detector

NASA Astrophysics Data System (ADS)

Yellampalle, Balakishore; McCormick, William B.; Wu, Hai-Shan; Sluch, Mikhail; Martin, Robert; Ice, Robert V.; Lemoff, Brian

2014-05-01

A key challenge for standoff explosive sensors is to distinguish explosives, with high confidence, from a myriad of unknown background materials that may have interfering spectral peaks. To meet this challenge a sensor needs to exhibit high specificity and high sensitivity in detection at low signal-to-noise ratio levels. We had proposed a Dual-Excitation- Wavelength Resonance-Raman Detector (DEWRRED) to address this need. In our previous work, we discussed various components designed at WVHTCF for a DEWRRED sensor. In this work, we show a completely assembled laboratory prototype of a DEWRRED sensor and utilize it to detect explosives from two standoff distances. The sensor system includes two novel, compact CW deep-Ultraviolet (DUV) lasers, a compact dual-band high throughput DUV spectrometer, and a highly-sensitive detection algorithm. We choose DUV excitation because Raman intensities from explosive traces are enhanced and fluorescence and solar background are not present. The DEWRRED technique exploits the excitation wavelength dependence of Raman signal strength, arising from complex interplay of resonant enhancement, self-absorption and laser penetration depth. We show measurements from >10 explosives/pre-cursor materials at different standoff distances. The sensor showed high sensitivity in explosive detection even when the signalto- noise ratio was close to one (~1.6). We measured receiver-operating-characteristics, which show a clear benefit in using the dual-excitation-wavelength technique as compared to a single-excitation-wavelength technique. Our measurements also show improved specificity using the amplitude variation information in the dual-excitation spectra.

In vivo delivery of recombinant human growth hormone from genetically engineered human fibroblasts implanted within Baxter immunoisolation devices.

PubMed

Josephs, S F; Loudovaris, T; Dixit, A; Young, S K; Johnson, R C

1999-01-01

Continuous delivery of therapeutic peptide to the systemic circulation would be the optimal treatment for a variety of diseases. The Baxter TheraCyte system is a membrane encapsulation system developed for implantation of tissues, cells such as endocrine cells or cell lines genetically engineered for therapeutic peptide delivery in vivo. To demonstrate the utility of this system, cell lines were developed which expressed human growth hormone (hGH) at levels exceeding 1 microgram per million cells per day. These were loaded into devices which were then implanted into juvenile nude rats. Significant levels of hGH of up to 2.5 ng/ml were detected in plasma throughout the six month duration of the study. In contrast, animals implanted with free cells showed peak plasma levels of 0.5 to 1.2 ng four days after implantation with no detectable hGH beyond 10 days. Histological examination of explanted devices showed they were vascularized and contained cells that were viable and morphologically healthy. After removal of the implants, no hGH could be detected which confirmed that the source of hGH was from cells contained within the device. The long term expression of human growth hormone as a model peptide has implications for the peptide therapies for a variety of human diseases using membrane encapsulated cells.

Changes in the vibration sensitivity and pressure pain thresholds in patients with burning mouth syndrome.

PubMed

Moura, Brenda de Souza; Ferreira, Natália Dos Reis; DosSantos, Marcos F; Janini, Maria Elisa Rangel

2018-01-01

To investigate the presence of changes in vibration detection and pressure pain threshold in patients with burning-mouth syndrome (BMS). Case-control study. The sample was composed of 30 volunteers, 15 with BMS and 15 in the control group. The pressure-pain threshold (PPT) and vibration-detection threshold (VDT) were examined. The clinical evaluation was complemented with the McGill Pain Questionnaire (MPQ), Douleur Neuropathique 4 (DN4) and Beck Depression and Anxiety Inventories (BDI and BAI, respectively). BMS subjects showed a statistically significant higher PPT in the tongue (p = 0.002), right (p = 0.001) and left (p = 0.004) face, and a significant reduction of the VDT in the tongue (p = 0.013) and right face (p = 0.030). Significant differences were also found when comparing the PPT and the VDT of distinct anatomical areas. However, a significant interaction (group × location) was only for the PPT. BMS subjects also showed significantly higher levels of depression (p = 0.01), as measured by the BDI, compared to controls; and a significant inverse correlation between the VDT in the left face and anxiety levels was detected. The study of somatosensory changes in BMS and its correlations with the clinical features as well as the levels of anxiety and depression expands current understanding of the neuropathic origin and the possible contribution of psychogenic factors related to this disease.

Roche/BIOTECON Diagnostics LightCycler foodproof L. monocytogenes detection kit in combination with ShortPrep foodproof II Kit. Performance-Tested Method 070401.

PubMed

Junge, Benjamin; Berghof-Jäger, Kornelia

2006-01-01

A method was developed for the detection of L. monocytogenes in food based on real-time polymerase chain reaction (PCR). This advanced PCR method was designed to reduce the time needed to achieve results from PCR reactions and to enable the user to monitor the amplification of the PCR product simultaneously, in real-time. After DNA isolation using the Roche/BIOTECON Diagnostics ShortPrep foodproof II Kit (formerly called Listeria ShortPrep Kit) designed for the rapid preparation of L. monocytogenes DNA for direct use in PCR, the real-time detection of L. monocytogenes DNA is performed by using the Roche/BIOTECON Diagnostics LightCycler foodproof L. monocytogenes Detection Kit. This kit provides primers and hybridization probes for sequence-specific detection, convenient premixed reagents, and different controls for reliable interpretation of results. For repeatability studies, 20 different foods, covering the 15 food groups recommended from the AOAC Research Institute (AOAC RI) for L. monocytogenes detection were analyzed: raw meats, fresh produce/vegetables, processed meats, seafood, egg and egg products, dairy (cultured/noncultured), spices, dry foods, fruit/juices, uncooked pasta, nuts, confectionery, pet food, food dyes and colorings, and miscellaneous. From each food 20, samples were inoculated with a low level (1-10 colony-forming units (CFU)/25 g) and 20 samples with a high level (10-50 CFU/25 g) of L. monocytogenes. Additionally, 5 uninoculated samples were prepared from each food. The food samples were examined with the test kits and in correlation with the cultural methods according to U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM) or U.S. Department of Agriculture (USDA)/Food Safety and Inspection Service (FSIS) Microbiology Laboratory Guidebook. After 48 h of incubation, the PCR method in all cases showed equal or better results than the reference cultural FDA/BAM or USDA/FSIS methods. Fifteen out of 20 tested food types gave exactly the same amount of positive samples for both methods in both inoculation levels. For 5 out of 20 foodstuffs, the PCR method resulted in more positives than the reference method after 48 h of incubation. Following AOAC RI definition, these were false positives because they were not confirmed by the reference method (false-positive rate for low inoculated foodstuffs: 5.4%; for high inoculated foodstuffs: 7.1%). Without calculating these unconfirmed positives, the PCR method showed equal sensitivity results compared to the alternative method. With the unconfirmed PCR-positives included into the calculations, the alternative PCR method showed a higher sensitivity than the microbiological methods (low inoculation level: 100 vs 98.0%; sensitivity rate: 1; high inoculation level: 99.7 vs 97.7%; sensitivity rate, 1). All in-house and independently tested uninoculated food samples were negative for L. monocytogenes. The ruggedness testing of both ShortPrep foodproof II Kit and Roche/BIOTECON LightCycler foodproof L. monocytogenes Detection Kit showed no noteworthy influences to any variation of the parameters component concentration, apparatus comparison, tester comparison, and sample volumes. In total, 102 L. monocytogenes isolates (cultures and pure DNA) were tested and detected for the inclusivity study, including all isolates claimed by the AOAC RI. The exclusivity study included 60 non-L. monocytogenes bacteria. None of the tested isolates gave a false-positive result; specificity was 100%. Three different lots were tested in the lot-to-lot study. All 3 lots gave equal results. The stability study was subdivided into 3 parts: long-term study, stress test, and freeze-defrost test. Three lots were tested in 4 time intervals within a period of 13 months. They all gave comparable results for all test intervals. For the stress test, LightCycler L. monocytogenes detection mixes were stored at different temperatures and tested at different time points during 1 month. Stable results were produced at all storage temperatures. The freeze-defrost analysis showed no noteworthy aggravation of test results. The independent validation study examined by Campden and Chorleywood Food Research Association Group (CCFRA) demonstrated again that the LightCycler L. monocytogenes detection system shows a comparable sensitivity to reference methods. With both the LightCycler PCR and BAM methods, 19 out of 20 inoculated food samples were detected. The 24 h PCR results generated by the LightCycler system corresponded directly with the FDA/BAM culture results. However, the 48 h PCR results did not relate exactly to the FDA/BAM results, as one sample found to be positive by the 48 h PCR could not be culturally confirmed and another sample which was negative by the 48 h PCR was culturally positive.

A robust object-based shadow detection method for cloud-free high resolution satellite images over urban areas and water bodies

NASA Astrophysics Data System (ADS)

Tatar, Nurollah; Saadatseresht, Mohammad; Arefi, Hossein; Hadavand, Ahmad

2018-06-01

Unwanted contrast in high resolution satellite images such as shadow areas directly affects the result of further processing in urban remote sensing images. Detecting and finding the precise position of shadows is critical in different remote sensing processing chains such as change detection, image classification and digital elevation model generation from stereo images. The spectral similarity between shadow areas, water bodies, and some dark asphalt roads makes the development of robust shadow detection algorithms challenging. In addition, most of the existing methods work on pixel-level and neglect the contextual information contained in neighboring pixels. In this paper, a new object-based shadow detection framework is introduced. In the proposed method a pixel-level shadow mask is built by extending established thresholding methods with a new C4 index which enables to solve the ambiguity of shadow and water bodies. Then the pixel-based results are further processed in an object-based majority analysis to detect the final shadow objects. Four different high resolution satellite images are used to validate this new approach. The result shows the superiority of the proposed method over some state-of-the-art shadow detection method with an average of 96% in F-measure.

Community Detection in Complex Networks via Clique Conductance.

PubMed

Lu, Zhenqi; Wahlström, Johan; Nehorai, Arye

2018-04-13

Network science plays a central role in understanding and modeling complex systems in many areas including physics, sociology, biology, computer science, economics, politics, and neuroscience. One of the most important features of networks is community structure, i.e., clustering of nodes that are locally densely interconnected. Communities reveal the hierarchical organization of nodes, and detecting communities is of great importance in the study of complex systems. Most existing community-detection methods consider low-order connection patterns at the level of individual links. But high-order connection patterns, at the level of small subnetworks, are generally not considered. In this paper, we develop a novel community-detection method based on cliques, i.e., local complete subnetworks. The proposed method overcomes the deficiencies of previous similar community-detection methods by considering the mathematical properties of cliques. We apply the proposed method to computer-generated graphs and real-world network datasets. When applied to networks with known community structure, the proposed method detects the structure with high fidelity and sensitivity. When applied to networks with no a priori information regarding community structure, the proposed method yields insightful results revealing the organization of these complex networks. We also show that the proposed method is guaranteed to detect near-optimal clusters in the bipartition case.

Highly sensitive detection of human IgG using a novel bio-barcode assay combined with DNA chip technology

NASA Astrophysics Data System (ADS)

Liu, Zhenbao; Zhou, Bo; Wang, Haiqing; Lu, Feng; Liu, Tianjun; Song, Cunxian; Leng, Xigang

2013-09-01

A simple and ultrasensitive detection of human IgG based on signal amplification using a novel bio-barcode assay and DNA chip technology was developed. The sensing platform was a sandwich system made up of antibody-modified magnetic microparticles (Ab-MMPs)/human IgG/Cy3-labeled single-stranded DNA and antibody-modified gold nanoparticles (Cy3-ssDNA-Ab-AuNPs). The MMPs (2.5 μm in diameter) modified with mouse anti-human IgG monoclonal-antibodies could capture human IgG and further be separated and enriched via a magnetic field. The AuNPs (13 nm in diameter) conjugated with goat anti-human IgG polyclonal-antibodies and Cy3-ssDNA could further combine with the human IgG/Ab-MMP complex. The Cy3-ssDNA on AuNPs was then released by TCEP to hybridize with the DNA chip, thus generating a detectable signal by the fluorescence intensity of Cy3. In order to improve detection sensitivity, a three-level cascaded signal amplification was developed: (1) The MMP enrichment as the first-level; (2) Large quantities of Cy3-ssDNA on AuNPs as the second-level; (3) The Cy3-ssDNA conjugate with DNA chip as the third-level. The highly sensitive technique showed an increased response of the fluorescence intensity to the increased concentration of human IgG through a detection range from 1 pg mL-1 to 10 ng mL-1. This sensing technique could not only improve the detection sensitivity for the low concentration of human IgG but also present a robust and efficient signal amplification model. The detection method has good stability, specificity, and reproducibility and could be applied in the detection of human IgG in the real samples.

Detection System of Sound Noise Level (SNL) Based on Condenser Microphone Sensor

NASA Astrophysics Data System (ADS)

Rajagukguk, Juniastel; Eka Sari, Nurdieni

2018-03-01

The research aims to know the noise level by using the Arduino Uno as data processing input from sensors and called as Sound Noise Level (SNL). The working principle of the instrument is as noise detector with the show notifications the noise level on the LCD indicator and in the audiovisual form. Noise detection using the sensor is a condenser microphone and LM 567 as IC op-amps, which are assembled so that it can detect the noise, which sounds are captured by the sensor will turn the tide of sinusoida voice became sine wave energy electricity (altering sinusoida electric current) that is able to responded to complaints by the Arduino Uno. The tool is equipped with a detector consists of a set indicator LED and sound well as the notification from the text on LCD 16*2. Work setting indicators on the condition that, if the measured noise > 75 dB then sound will beep, the red LED will light up indicating the status of the danger. If the measured value on the LCD is higher than 56 dB, sound indicator will be beep and yellow LED will be on indicating noisy. If the noise measured value <55 dB, sound indicator will be quiet indicating peaceful from noisy. From the result of the research can be explained that the SNL is capable to detecting and displaying noise level with a measuring range 50-100 dB and capable to delivering the notification noise in audiovisual.

Environmental and socio-demographic individual, family and neighborhood factors associated with children intestinal parasitoses at Iguazú, in the subtropical northern border of Argentina

PubMed Central

De Angelo, Carlos; Nuñez, Pablo; Salas, Martín; Motta, Carlos E.; Chiaretta, Alicia; Salomón, Oscar D.; Liang, Song

2017-01-01

Background Intestinal parasitoses are a major concern for public health, especially in children from middle and low-income populations of tropical and subtropical areas. We examined the presence and co-infection of parasites in humans as well as parasitic environmental contamination in Puerto Iguazú, Argentina. We explored the environmental and socio-demographic characteristics of the persistence of parasites in children and their environment. Methodology/Principal findings This cross-section survey was conducted among children population comprised into the area of the public health care centers of Iguazú during June 2013 to May 2016. Copro-parasitological status of 483 asymptomatic children was assessed. Simultaneously, a design-based sampling of 744 soil samples and 530 dog feces was used for characterize the environmental contamination. The 71.5% of these sites were contaminated. Sixteen genera were detected in the environment being hookworms (62.0%) the main pathogens group detected followed by Toxocara spp (16.3%), Trichuris spp (15.2%) and Giardia (6.5%). Total children prevalence raised 58.8%, detecting twelve genera of parasite with Giardia intestinalis as the most prevalent pathogen (29.0%) followed by Enterobius vermicularis (23.0%), Hymenolepis nana (12.4%) and hookworms (4.4%). Through questionnaires and census data, we characterized the socio-demographics conditions at an individual, family and neighborhood levels. A multi-level analysis including environmental contamination data showed that the ´presence of parasites´ was mostly determined by individual (e.g. age, playing habits, previous treatment) and household level (e.g. UBN, WASH, mother's literacy) determinants. Remarkably, to define the level of ‘parasite co-infection’, besides individual and household characteristics, environmental factors at a neighborhood level were important. Conclusion/Significance Our work represents the major survey of intestinal parasites in human and environmental samples developed in the region. High prevalence was detected in the children population as well as in their environment. This work shows the importance of considering and promoting multi-level actions over the identified determinants to face this public health problem from integrative approaches. PMID:29155829

Environmental and socio-demographic individual, family and neighborhood factors associated with children intestinal parasitoses at Iguazú, in the subtropical northern border of Argentina.

PubMed

Rivero, Maria Romina; De Angelo, Carlos; Nuñez, Pablo; Salas, Martín; Motta, Carlos E; Chiaretta, Alicia; Salomón, Oscar D; Liang, Song

2017-11-01

Intestinal parasitoses are a major concern for public health, especially in children from middle and low-income populations of tropical and subtropical areas. We examined the presence and co-infection of parasites in humans as well as parasitic environmental contamination in Puerto Iguazú, Argentina. We explored the environmental and socio-demographic characteristics of the persistence of parasites in children and their environment. This cross-section survey was conducted among children population comprised into the area of the public health care centers of Iguazú during June 2013 to May 2016. Copro-parasitological status of 483 asymptomatic children was assessed. Simultaneously, a design-based sampling of 744 soil samples and 530 dog feces was used for characterize the environmental contamination. The 71.5% of these sites were contaminated. Sixteen genera were detected in the environment being hookworms (62.0%) the main pathogens group detected followed by Toxocara spp (16.3%), Trichuris spp (15.2%) and Giardia (6.5%). Total children prevalence raised 58.8%, detecting twelve genera of parasite with Giardia intestinalis as the most prevalent pathogen (29.0%) followed by Enterobius vermicularis (23.0%), Hymenolepis nana (12.4%) and hookworms (4.4%). Through questionnaires and census data, we characterized the socio-demographics conditions at an individual, family and neighborhood levels. A multi-level analysis including environmental contamination data showed that the ´presence of parasites´ was mostly determined by individual (e.g. age, playing habits, previous treatment) and household level (e.g. UBN, WASH, mother's literacy) determinants. Remarkably, to define the level of 'parasite co-infection', besides individual and household characteristics, environmental factors at a neighborhood level were important. Our work represents the major survey of intestinal parasites in human and environmental samples developed in the region. High prevalence was detected in the children population as well as in their environment. This work shows the importance of considering and promoting multi-level actions over the identified determinants to face this public health problem from integrative approaches.

Total mercury levels in commercial fish species from Italian fishery and aquaculture.

PubMed

Di Lena, Gabriella; Casini, Irene; Caproni, Roberto; Fusari, Andrea; Orban, Elena

2017-06-01

Total mercury levels were measured in 42 commercial fish species caught off the Central Adriatic and Tyrrhenian coasts of Italy and in 6 aquaculture species. The study on wild fish covered species differing in living habitat and trophic level. The study on farmed fish covered marine and freshwater species from intensive and extensive aquaculture and their feed. Mercury levels were analysed by thermal decomposition-amalgamation-atomic absorption spectrophotometry. Total mercury concentrations in the muscle of wild fish showed a high variability among species (0.025-2.20 mg kg -1 wet weight). The lowest levels were detected in low trophic-level demersal and pelagic-neritic fish and in young individuals of high trophic-level species. Levels exceeding the European Commission limits were found in large-size specimens of high trophic-level pelagic and demersal species. Fish from intensive farming showed low levels of total mercury (0.008-0.251 mg kg -1 ). Fish from extensive rearing showed variable contamination levels, depending on the area of provenience. An estimation of the human intake of mercury associated to the consumption of the studied fish and its comparison with the tolerable weekly intake is provided.

Using 2 H labelling to improve the NMR detectability of pyridine and its derivatives by SABRE.

PubMed

Norcott, Philip; Burns, Michael J; Rayner, Peter J; Mewis, Ryan E; Duckett, Simon B

2018-07-01

By introducing a range of 2 H labels into pyridine and the para-substituted agents, methyl isonicotinate and isonicotinamide, we significantly improve their NMR detectability in conjunction with the signal amplification by reversible exchange process. We describe how the rates of T 1 relaxation for the remaining 1 H nuclei are increased and show how this leads to a concomitant increase in the level of 1 H and 13 C hyperpolarization that can ultimately be detected. © 2017 The Authors. Magnetic Resonance in Chemistry published by John Wiley & Sons Ltd.

Impacts of climate-induced changes on the distribution of pesticides residues in water and sediment of Lake Naivasha, Kenya.

PubMed

Otieno, Peter O; Owuor, P Okinda; Lalah, Joseph O; Pfister, Gerd; Schramm, Karl-Werner

2013-03-01

This study reports evidence of increased chlorpyrifos contamination in sediment and water in Lake Naivasha following its intensive application in the horticultural farms in the catchment area. Analytical results show that levels of chlorpyrifos residues were influenced by climate-induced rainfall pattern with higher levels reported during period of heavy precipitation with significant decrease during low rainfall. On average, the levels ranged between 14.8 and 32.8 ng g(-1) in sediment during rainy season compared to a range of 8.5-16.6 ng g(-1) in the dry season. Additionally, the mean concentration of chlorpyrifos in water ranged between 8.61 and 22.4 μg L(-1) during rainy season and below detection limit (bdl) -13.6 μg L(-1) in dry season as quantified by enzyme-linked immunosorbent assay. Meanwhile, independent t test analysis indicated that there was significant difference in concentration at p ≤ 0.05 between the seasons with respect to sediment and water samples. This demonstrated that climate-induced variations had considerable influence on contamination. While diazinon and carbofuran were equally applied intensively, their levels were below the detection limit in the all the samples analyzed. ELISA results were validated by the capillary-HPLC photodiode-array detector instrument analysis, and statistical comparison showed no significant difference between them. It was evident that chlorpyrifos residues determination in water and sediment by ELISA can be a useful strategy in environmental management and monitoring program, and a complimentary analytical tool to high performance liquid chromatography. Levels of chlorpyrifos detected in sediment and water were found to exceed recommended criteria for protection of aquatic life and preservation of water quality and may be hazardous if not regularly monitored.

Detection of contaminated pixels based on the short-term continuity of NDVI and correction using spatio-temporal continuity

NASA Astrophysics Data System (ADS)

Cho, A.-Ra; Suh, Myoung-Seok

2013-08-01

The present study developed and assessed a correction technique (CSaTC: Correction based on Spatial and Temporal Continuity) for the detection and correction of contaminated Normalized Difference Vegetation Index (NDVI) time series data. Global Inventory Modeling and Mapping Studies (GIMMS) NDVI data from 1982 to 2006 with a 15-day period and an 8-km spatial resolution was used. CSaTC utilizes short-term continuity of vegetation to detect contaminated pixels, and then, corrects the detected pixels using the spatio-temporal continuity of vegetation. CSaTC was applied to the NDVI data over the East Asian region, which exhibits diverse seasonal and interannual variations in vegetation activities. The correction skill of CSaTC was compared to two previously applied methods, IDR (iterative Interpolation for Data Reconstruction) and Park et al. (2011) using GIMMS NDVI data. CSaTC reasonably resolved the overcorrection and spreading phenomenon caused by excessive correction of Park et al. (2011). The validation using the simulated NDVI time series data showed that CSaTC shows a systematically better correction skill in bias and RMSE irrespective of phenology types of vegetation and noise levels. In general, CSaTC showed a good recovery of the contaminated data appearing over the short-term period on a level similar to that obtained using the IDR technique. In addition, it captured the multi-peak of NDVI, and the germination and defoliating patterns more accurately than that by IDR, which overly compensates for seasons with a high temporal variation and where NDVI data exhibit multi-peaks.

Noninvasive and Painless Urine Glucose Detection by Using Computer-based Polarimeter

NASA Astrophysics Data System (ADS)

Sutrisno; Laksono, Y. A.; Hidayat, N.

2017-05-01

Diabetes kills millions of people worldwide each year. It challenges us as researchers to give contribution in early diagnosis to ensure a healthy life. As a matter of fact, common glucose testing devices that have been widely used so far are, at least, glucose meter and urine glucose test strip. The glucose meter ordinarily requires blood taken from patient’s finger. The glucose test strip uses patient’s urine but records unspecific urine glucose level, since the strip only provides the glucose level in some particular ranges. Instead of detecting the glucose level in blood and using the non-specific technique, a noninvasive and painless technique that can detect glucose level accurately will provide a more feasible approach for diabetes diagnosis. The noninvasive and painless urine glucose level monitoring by means of computer-based polarimeter is presented in this paper. The instrument consisted of a power source, a sample box, a light sensor, a polarizer, an analyzer, an analog to digital converter (ADC), and a computer. The concentration of urine glucose concentration was evaluated from the curve of the change in detected optical rotation angle and output potential by the computer-based polarimeter. Statistical analyses by means of Gaussian fitting and linear regression were applied to investigate the rotation angle and urine glucose concentration, respectively. From our experiment, the urine glucose level, measured by glucose test strips, of the normal patient was 100 mg/dl, and the diabetic patient was 500 mg/dl. Our polarimeter even read more precise values for the urine glucose concentrations of those normal and diabetic of the same patients, i.e. 50.61 mg/dl and 502.41 mg/dl, respectively. In other words, the results showed that our polarimeter was able to quantitatively measure the urine glucose level more accurate than urine glucose test strips. Hence, this computer-based polarimeter could be used as an alternative for early detection of urine glucose with noninvasive and painless characteristics.

Occurrence of aflatoxin M₁ in commercial pasteurized milk samples in Sari, Mazandaran province, Iran.

PubMed

Mohammadi, Hamidreza; Shokrzadeh, Mohammad; Aliabadi, Zahra; Riahi-Zanjani, Bamdad

2016-05-01

The frequency and levels of aflatoxin M1 (AFM1) in pasteurized milk samples in Sari, located in Mazandaran province, Iran, were determined by enzyme immunoassay. Seventy-six samples of pasteurized milk from different retail stores were randomly collected over four seasons during the year 2015. AFM1 contamination was detected in all milk samples. The mean concentration of aflatoxin M1 was 65.8 ng/l, with a range of 11.7-106.6 ng/l. The highest AFM1 level was detected in milk samples collected during spring. Forty-six (60.53 %) samples had AFM1 levels that exceeded the maximum acceptable levels (50 ng/l) recommended by the European Union (EU). Comparison of these results with previously published data for AFM1 in milk in Iran shows that the percentage of samples exceeding the EU maximum level is consistently high over the years, indicating a general problem related to AFB1 contamination in dairy feedingstuff.

Pesticide-contaminated feeds in integrated grass carp aquaculture: toxicology and bioaccumulation.

PubMed

Pucher, J; Gut, T; Mayrhofer, R; El-Matbouli, M; Viet, P H; Ngoc, N T; Lamers, M; Streck, T; Focken, U

2014-02-19

Effects of dissolved pesticides on fish are widely described, but little is known about effects of pesticide-contaminated feeds taken up orally by fish. In integrated farms, pesticides used on crops may affect grass carp that feed on plants from these fields. In northern Vietnam, grass carp suffer seasonal mass mortalities which may be caused by pesticide-contaminated plants. To test effects of pesticide-contaminated feeds on health and bioaccumulation in grass carp, a net-cage trial was conducted with 5 differently contaminated grasses. Grass was spiked with 2 levels of trichlorfon/fenitrothion and fenobucarb. Unspiked grass was used as a control. Fish were fed at a daily rate of 20% of body mass for 10 d. The concentrations of fenitrothion and fenobucarb in pond water increased over time. Effects on fish mortality were not found. Fenobucarb in feed showed the strongest effects on fish by lowering feed uptake, deforming the liver, increasing blood glucose and reducing cholinesterase activity in blood serum, depending on feed uptake. Fenobucarb showed increased levels in flesh in all treatments, suggesting bio-concentration. Trichlorfon and fenitrothion did not significantly affect feed uptake but showed concentration-dependent reduction of cholinesterase activity and liver changes. Fenitrothion showed bioaccumulation in flesh which was dependant on feed uptake, whereas trichlorfon was only detected in very low concentrations in all treatments. Pesticide levels were all detected below the maximum residue levels in food. The pesticide-contaminated feeds tested did not cause mortality in grass carp but were associated with negative physiological responses and may increase susceptibility to diseases.

The generation of knock-in mice expressing fluorescently tagged galanin receptors 1 and 2

PubMed Central

Kerr, Niall; Holmes, Fiona E.; Hobson, Sally-Ann; Vanderplank, Penny; Leard, Alan; Balthasar, Nina; Wynick, David

2015-01-01

The neuropeptide galanin has diverse roles in the central and peripheral nervous systems, by activating the G protein-coupled receptors Gal1, Gal2 and the less studied Gal3 (GalR1–3 gene products). There is a wealth of data on expression of Gal1–3 at the mRNA level, but not at the protein level due to the lack of specificity of currently available antibodies. Here we report the generation of knock-in mice expressing Gal1 or Gal2 receptor fluorescently tagged at the C-terminus with, respectively, mCherry or hrGFP (humanized Renilla green fluorescent protein). In dorsal root ganglia (DRG) neurons expressing the highest levels of Gal1-mCherry, localization to the somatic cell membrane was detected by live-cell fluorescence and immunohistochemistry, and that fluorescence decreased upon addition of galanin. In spinal cord, abundant Gal1-mCherry immunoreactive processes were detected in the superficial layers of the dorsal horn, and highly expressing intrinsic neurons of the lamina III/IV border showed both somatic cell membrane localization and outward transport of receptor from the cell body, detected as puncta within cell processes. In brain, high levels of Gal1-mCherry immunofluorescence were detected within thalamus, hypothalamus and amygdala, with a high density of nerve endings in the external zone of the median eminence, and regions with lesser immunoreactivity included the dorsal raphe nucleus. Gal2-hrGFP mRNA was detected in DRG, but live-cell fluorescence was at the limits of detection, drawing attention to both the much lower mRNA expression than to Gal1 in mice and the previously unrecognized potential for translational control by upstream open reading frames (uORFs). PMID:26292267

Detection of fibrin generation alterations in dogs with haemangiosarcoma using resonance thrombography.

PubMed

Mischke, R; Wohlsein, P; Schoon, H-A

2005-01-01

The objective of the study was to examine the alterations of fibrin generation in dogs with haemangiosarcoma using resonance thrombography. The second objective was to evaluate the sensitivity of this method for the detection of hypofibrinogenaemia and/or increased fibrin(ogen) degradation product (FDP) concentration. Resonance thrombogram (RTG) measurements with two different instruments were performed in 30 unselected dogs with haemangiosarcoma, 14 of which had decreased fibrinogen and 28 of which had an increased FDP concentration (p<0.0001). The RTG-reaction time was less sensitive than the fibrin formation time (RTG-f) and fibrin amplitude (RTG-F). The RTG-f and RTG-F indicated reliably a decrease in fibrinogen concentration (sensitivity: 0.93). The sensitivity of detection of increased FDP levels was considerably higher than that of thrombin time. However, false-negative results were found even at FDP concentrations > or =120 mg/l, especially in cases with high fibrinogen level. Both machines showed similar sensitivity. The results of this study indicate that canine haemangiosarcoma is frequently associated with severe alterations of fibrin generation due to low fibrinogen and high FDP levels leading to distinct RTG abnormalities. The global test RTG reacts sensitively to a decreased fibrinogen level whereas its accuracy to detect FDP concentrations occurring under pathophysiological conditions is limited. A significant alteration of fibrin generation induced by FDPs may not occur until the serum FDP concentration exceeds 60 mg/l.

Pitfalls in the detection of cholesterol in Huntington's disease models.

PubMed

Marullo, Manuela; Valenza, Marta; Leoni, Valerio; Caccia, Claudio; Scarlatti, Chiara; De Mario, Agnese; Zuccato, Chiara; Di Donato, Stefano; Carafoli, Ernesto; Cattaneo, Elena

2012-10-11

Background Abnormalities in brain cholesterol homeostasis have been reported in Huntington's disease (HD), an adult-onset neurodegenerative disorder caused by an expansion in the number of CAG repeats in the huntingtin (HTT) gene. However, the results have been contradictory with respect to whether cholesterol levels increase or decrease in HD models. Biochemical and mass spectrometry methods show reduced levels of cholesterol precursors and cholesterol in HD cells and in the brains of several HD animal models. Abnormal brain cholesterol homeostasis was also inferred from studies in HD patients. In contrast, colorimetric and enzymatic methods indicate cholesterol accumulation in HD cells and tissues. Here we used several methods to investigate cholesterol levels in cultured cells in the presence or absence of mutant HTT protein. Results Colorimetric and enzymatic methods with low sensitivity gave variable results, whereas results from a sensitive analytical method, gas chromatography-mass spectrometry, were more reliable. Sample preparation, high cell density and cell clonality also influenced the detection of intracellular cholesterol. Conclusions Detection of cholesterol in HD samples by colorimetric and enzymatic assays should be supplemented by detection using more sensitive analytical methods. Care must be taken to prepare the sample appropriately. By evaluating lathosterol levels using isotopic dilution mass spectrometry, we confirmed reduced cholesterol biosynthesis in knock-in cells expressing the polyQ mutation in a constitutive or inducible manner. *Correspondence should be addressed to Elena Cattaneo: elena.cattaneo@unimi.it.

Analysis of the origin and importance of acetone and isopropanol levels in the blood of the deceased for medico-legal testimony.

PubMed

Borowska-Solonynko, A; Siwińska-Ziółkowska, A; Piotrkowicz, M; Wysmołek, M; Demkow, M

2014-01-01

The aim of the study was to analyze the incidence of acetone and isopropanol in the blood of the deceased, and to assess cases in which the compounds have been detected with a focus on their origin and usefulness for medico-legal testimony. The study material consisted of results of tests detecting ethyl alcohol and reports of autopsies performed at the Department of Forensic Medicine, Medical University of Warsaw, from January 2008 to April 2009 - a total of 2,475 cases. The test group proper (group B) comprised only those cases in which acetone was detected in blood, either with or without isopropanol [n = 202 (8.2%)]. The blood levels of isopropanol varied depending on the cause of death. The need for differentiating the origin of isopropanol in the case of its presence in the blood of the deceased was pointed out. The results of the present study show that the differentiation should be based on the isopropanol and acetone concentration ratio, as isopropanol concentration alone is not sufficient for preparing expert opinions. Even high concentrations of isopropanol, when accompanied by even higher concentrations of acetone, imply that isopropanol could have been formed as a result of acetone transformations. Isopropanol concentrations exceeding acetone levels strongly point to the exogenous origin of isopropanol, particularly when high levels of ethanol are concurrently detected.

Performance evaluation of FlowCytomix assays to quantify cytokines in patients with rheumatoid arthritis

PubMed Central

Wang, Xuefeng; Dong, Liyang; Liang, Yong; Ni, Hongchang; Tang, Jun; Xu, Chengcheng; Zhou, Yuepeng; Su, Yuting; Wang, Jun; Chen, Deyu; Mao, Chaoming

2015-01-01

Objectives: To compare the cytokine profile in RA patients and healthy control by using two methods-FlowCytomix assay and traditional ELISA. Methods: Cytokine levels were evaluated by FlowCytomix assay and ELISA in serum and supernatants of peripheral blood mononuclear cells (PBMC) cultures with and without stimulation by phytohaemagglutinin (PHA). Results: The levels of IL-6, IL-1β, and TNF-α were significantly higher in sera of RA patients than those of healthy controls. The levels of IL-22, IL-6, IL-1β, TNF-α, and IL-10 were higher in unstimulated PBMC culture supernatant of RA patients than those of healthy controls. PHA stimulation significantly increased the production of proinflammatory cytokines from PBMC with RA patients. Compared with detectable cytokine levels in sera, cytokine concentration in the supernatant of PBMCs was remarkably higher. FlowCytomix and ELISA showed significant correlation in detecting cytokines. However, the FlowCytomix assay detected more cytokines than ELISA. Conclusion: The supernatant of PBMCs provide a fine condition for the study of cytokine production because of the lack of interference factors in sera. The FlowCytomix assay is more sensitive than ELISA in detecting cytokines from RA patients. Multiple cytokine signatures using FlowCytomix assay may represent a more realistic approach in the future of personalized medicine in RA. PMID:26629129

On the Statistical Analysis of X-ray Polarization Measurements

NASA Technical Reports Server (NTRS)

Strohmayer, T. E.; Kallman, T. R.

2013-01-01

In many polarimetry applications, including observations in the X-ray band, the measurement of a polarization signal can be reduced to the detection and quantification of a deviation from uniformity of a distribution of measured angles of the form alpha plus beta cosine (exp 2)(phi - phi(sub 0) (0 (is) less than phi is less than pi). We explore the statistics of such polarization measurements using both Monte Carlo simulations as well as analytic calculations based on the appropriate probability distributions. We derive relations for the number of counts required to reach a given detection level (parameterized by beta the "number of sigma's" of the measurement) appropriate for measuring the modulation amplitude alpha by itself (single interesting parameter case) or jointly with the position angle phi (two interesting parameters case). We show that for the former case when the intrinsic amplitude is equal to the well known minimum detectable polarization (MDP) it is, on average, detected at the 3sigma level. For the latter case, when one requires a joint measurement at the same confidence level, then more counts are needed, by a factor of approximately equal to 2.2, than that required to achieve the MDP level. We find that the position angle uncertainty at 1sigma confidence is well described by the relation sigma(sub pi) equals 28.5(degrees) divided by beta.

Staphylococcus aureus methicillin resistance detected by HPLC-MS/MS targeted metabolic profiling.

PubMed

Schelli, Katie; Rutowski, Joshua; Roubidoux, Julia; Zhu, Jiangjiang

2017-03-15

Recently, novel bioanalytical methods, such as NMR and mass spectrometry based metabolomics approaches, have started to show promise in providing rapid, sensitive and reproducible detection of Staphylococcus aureus antibiotic resistance. Here we performed a proof-of-concept study focused on the application of HPLC-MS/MS based targeted metabolic profiling for detecting and monitoring the bacterial metabolic profile changes in response to sub-lethal levels of methicillin exposure. One hundred seventy-seven targeted metabolites from over 20 metabolic pathways were specifically screened and one hundred and thirty metabolites from in vitro bacterial tests were confidently detected from both methicillin susceptible and methicillin resistant Staphylococcus aureus (MSSA and MRSA, respectively). The metabolic profiles can be used to distinguish the isogenic pairs of MSSA strains from MRSA strains, without or with sub-lethal levels of methicillin exposure. In addition, better separation between MSSA and MRSA strains can be achieved in the latter case using principal component analysis (PCA). Metabolite data from isogenic pairs of MSSA and MRSA strains were further compared without and with sub-lethal levels of methicillin exposure, with metabolic pathway analyses additionally performed. Both analyses suggested that the metabolic activities of MSSA strains were more susceptible to the perturbation of the sub-lethal levels of methicillin exposure compared to the MRSA strains. Copyright © 2016 Elsevier B.V. All rights reserved.

[Exposure to organic halogen compounds in drinking water of 9 Italian regions: exposure to chlorites, chlorates, thrihalomethanes, trichloroethylene and tetrachloroethylene].

PubMed

Fantuzzi, G; Aggazzotti, G; Righi, E; Predieri, G; Giacobazzi, P; Kanitz, S; Barbone, F; Sansebastiano, G; Ricci, C; Leoni, V; Fabiani, L; Triassi, M

2007-01-01

This study investigated the exposure to organohalogens compounds in drinking water from 9 Italian towns (Udine, Genova, Parma, Modena, Siena, Roma, L'Aquila, Napoli and Catania). Overall, 1199 samples collected from 72 waterworks were analyzed. THMs, trichloroethylene and tetrachloroethylene were evaluated using the head-space gas chromatographic technique (detection limit of 0.01 microg/l; chlorite and chlorate analysis was performed by ion chromatography (detection limit of 20 microg/l). THMs were evidenced in 925 samples (77%) (median value: 1.12 micro/l; range: 0.01-54 mciro/l) and 7 were higher than the THMs Italian limit of 30 microg/l. Chlorite and chlorate levels were higher than the detection limit in 45% for chlorite and in 34% for chlorate samples; median values were 221 microg/l and 76 microg/l, respectively. Chlorite values were higher than the chlorite Italian limit (700 microg/l) in 35 samples (8.7%). Trichloroethylene and tetrachloroethylene were measured in 29% and 44% of the investigated samples and showed values lower than the Italian limit (highest levels of 6 microg/l and 9 microg/l, respectively). The low levels detected of THMs, trichloroethylene and tetrachloroethylene have no potentials effects on human health, whereas, the levels of chlorite and chlorates should be further evaluated and their potential effects for the populations using these drinking waters, better understood.

Assessment of airborne environmental bacteria and related factors in 25 underground railway stations in Seoul, Korea

NASA Astrophysics Data System (ADS)

Hwang, Sung Ho; Yoon, Chung Sik; Ryu, Kyong Nam; Paik, Samuel Y.; Cho, Jun Ho

2010-05-01

This study assessed bacterial concentrations in indoor air at 25 underground railway stations in Seoul, Korea, and investigated various related factors including the presence of platform screen doors (PSD), depth of the station, year of construction, temperature, relative humidity, and number of passengers. A total of 72 aerosol samples were collected from all the stations. Concentrations of total airborne bacteria (TAB) ranged from not detected (ND) to 4997 CFU m -3, with an overall geometric mean (GM) of 191 CFU m -3. Airborne bacteria were detected at 23 stations (92%) and Gram-negative bacteria (GNB) were detected at two stations (8%). TAB concentrations of four stations (16%) exceeded 800 CFU m -3, the Korea indoor bio-aerosol guideline. The results of the study showed that TAB concentrations at the stations without PSD showed higher TAB concentrations than those with PSD, though not at statistically significant levels. TAB concentrations of deeper stations revealed significantly higher levels than those of shallower stations. Based on this study, it is recommended that mitigation measures be applied to improve the indoor air quality (IAQ) of underground railway stations in Seoul, with focused attention on deeper stations.

Asynchronous detection of kinesthetic attention during mobilization of lower limbs using EEG measurements.

PubMed

Melinscak, Filip; Montesano, Luis; Minguez, Javier

2016-02-01

Attention is known to modulate the plasticity of the motor cortex, and plasticity is crucial for recovery in motor rehabilitation. This study addresses the possibility of using an EEG-based brain-computer interface (BCI) to detect kinesthetic attention to movement. A novel experiment emulating physical rehabilitation was designed to study kinesthetic attention. The protocol involved continuous mobilization of lower limbs during which participants reported levels of attention to movement-from focused kinesthetic attention to mind wandering. For this protocol an asynchronous BCI detector of kinesthetic attention and deliberate mind wandering was designed. EEG analysis showed significant differences in theta, alpha, and beta bands, related to the attentional state. These changes were further pinpointed to bands relative to the frequency of the individual alpha peak. The accuracy of the designed BCI ranged between 60.8% and 68.4% (significantly above chance level), depending on the used analysis window length, i.e. acceptable detection delay. This study shows it is possible to use self-reporting to study attention-related changes in EEG during continuous mobilization. Such a protocol is used to develop an asynchronous BCI detector of kinesthetic attention, with potential applications to motor rehabilitation.

Asynchronous detection of kinesthetic attention during mobilization of lower limbs using EEG measurements

NASA Astrophysics Data System (ADS)

Melinscak, Filip; Montesano, Luis; Minguez, Javier

2016-02-01

Objective. Attention is known to modulate the plasticity of the motor cortex, and plasticity is crucial for recovery in motor rehabilitation. This study addresses the possibility of using an EEG-based brain-computer interface (BCI) to detect kinesthetic attention to movement. Approach. A novel experiment emulating physical rehabilitation was designed to study kinesthetic attention. The protocol involved continuous mobilization of lower limbs during which participants reported levels of attention to movement—from focused kinesthetic attention to mind wandering. For this protocol an asynchronous BCI detector of kinesthetic attention and deliberate mind wandering was designed. Main results. EEG analysis showed significant differences in theta, alpha, and beta bands, related to the attentional state. These changes were further pinpointed to bands relative to the frequency of the individual alpha peak. The accuracy of the designed BCI ranged between 60.8% and 68.4% (significantly above chance level), depending on the used analysis window length, i.e. acceptable detection delay. Significance. This study shows it is possible to use self-reporting to study attention-related changes in EEG during continuous mobilization. Such a protocol is used to develop an asynchronous BCI detector of kinesthetic attention, with potential applications to motor rehabilitation.

Urine TREM-1 as a marker of urinary tract infection in children.

PubMed

Sierra-Diaz, Erick; Bravo Cuéllar, Alejandro; Ortiz Lazareno, Pablo Cesar; García Gutiérrez, Mariana; Georgina, Hernandez Flores; Anaya Prado, Roberto

2017-04-01

Objective Triggering receptor expressed on myeloid cells (TREM)-1 is a receptor that is thought to improve recognition of patients with true infection. In this study, we investigated whether Triggering receptor expressed on myeloid cells (TREM-1) is present in urine samples from children with urinary tract infection (UTI) and in samples from healthy children. Methods A total of 128 samples met the inclusion criteria for the study. Urine samples were processed for culture and urinalysis as a regular protocol for patients with UTI. Samples were classified according to culture and urinalysis results. TREM-1 protein expression was detected with flow cytometry and sTREM-1 was assessed by ELISA. Results Flow cytometry showed detectable expression of TREM-1 in 100% of samples, UTI and non-UTI groups ( p < 0.001). Mean fluorescence intensity of TREM-1 was different between the groups ( p < 0.001). Levels of sTREM-1 were detected in patients with UTI, but not in non-UTI patients. Conclusions All of our patients (healthy and diseased) showed TREM-1 expression. However, TREM-1 levels in patients with UTI tend to be higher and are associated with increased neutrophils and cytokine activity induced by bacteria.

Urine TREM-1 as a marker of urinary tract infection in children

PubMed Central

Sierra-Diaz, Erick; Ortiz Lazareno, Pablo Cesar; García Gutiérrez, Mariana; Georgina, Hernandez Flores; Anaya Prado, Roberto

2017-01-01

Objective Triggering receptor expressed on myeloid cells (TREM)-1 is a receptor that is thought to improve recognition of patients with true infection. In this study, we investigated whether Triggering receptor expressed on myeloid cells (TREM-1) is present in urine samples from children with urinary tract infection (UTI) and in samples from healthy children. Methods A total of 128 samples met the inclusion criteria for the study. Urine samples were processed for culture and urinalysis as a regular protocol for patients with UTI. Samples were classified according to culture and urinalysis results. TREM-1 protein expression was detected with flow cytometry and sTREM-1 was assessed by ELISA. Results Flow cytometry showed detectable expression of TREM-1 in 100% of samples, UTI and non-UTI groups (p < 0.001). Mean fluorescence intensity of TREM-1 was different between the groups (p < 0.001). Levels of sTREM-1 were detected in patients with UTI, but not in non-UTI patients. Conclusions All of our patients (healthy and diseased) showed TREM-1 expression. However, TREM-1 levels in patients with UTI tend to be higher and are associated with increased neutrophils and cytokine activity induced by bacteria. PMID:28367708

Frequency modulation detection in cochlear implant subjects

NASA Astrophysics Data System (ADS)

Chen, Hongbin; Zeng, Fan-Gang

2004-10-01

Frequency modulation (FM) detection was investigated in acoustic and electric hearing to characterize cochlear-implant subjects' ability to detect dynamic frequency changes and to assess the relative contributions of temporal and spectral cues to frequency processing. Difference limens were measured for frequency upward sweeps, downward sweeps, and sinusoidal FM as a function of standard frequency and modulation rate. In electric hearing, factors including electrode position and stimulation level were also studied. Electric hearing data showed that the difference limen increased monotonically as a function of standard frequency regardless of the modulation type, the modulation rate, the electrode position, and the stimulation level. In contrast, acoustic hearing data showed that the difference limen was nearly a constant as a function of standard frequency. This difference was interpreted to mean that temporal cues are used only at low standard frequencies and at low modulation rates. At higher standard frequencies and modulation rates, the reliance on the place cue is increased, accounting for the better performance in acoustic hearing than for electric hearing with single-electrode stimulation. The present data suggest a speech processing strategy that encodes slow frequency changes using lower stimulation rates than those typically employed by contemporary cochlear-implant speech processors. .

Psychophysical Models for Signal Detection with Time Varying Uncertainty. Ph.D. Thesis

NASA Technical Reports Server (NTRS)

Gai, E.

1975-01-01

Psychophysical models for the behavior of the human operator in detection tasks which include change in detectability, correlation between observations and deferred decisions are developed. Classical Signal Detection Theory (SDT) is discussed and its emphasis on the sensory processes is contrasted to decision strategies. The analysis of decision strategies utilizes detection tasks with time varying signal strength. The classical theory is modified to include such tasks and several optimal decision strategies are explored. Two methods of classifying strategies are suggested. The first method is similar to the analysis of ROC curves, while the second is based on the relation between the criterion level (CL) and the detectability. Experiments to verify the analysis of tasks with changes of signal strength are designed. The results show that subjects are aware of changes in detectability and tend to use strategies that involve changes in the CL's.

A habituation based approach for detection of visual changes in surveillance camera

NASA Astrophysics Data System (ADS)

Sha'abani, M. N. A. H.; Adan, N. F.; Sabani, M. S. M.; Abdullah, F.; Nadira, J. H. S.; Yasin, M. S. M.

2017-09-01

This paper investigates a habituation based approach in detecting visual changes using video surveillance systems in a passive environment. Various techniques have been introduced for dynamic environment such as motion detection, object classification and behaviour analysis. However, in a passive environment, most of the scenes recorded by the surveillance system are normal. Therefore, implementing a complex analysis all the time in the passive environment resulting on computationally expensive, especially when using a high video resolution. Thus, a mechanism of attention is required, where the system only responds to an abnormal event. This paper proposed a novelty detection mechanism in detecting visual changes and a habituation based approach to measure the level of novelty. The objective of the paper is to investigate the feasibility of the habituation based approach in detecting visual changes. Experiment results show that the approach are able to accurately detect the presence of novelty as deviations from the learned knowledge.

Comparative analysis of toxin detection in biological and enviromental samples

NASA Astrophysics Data System (ADS)

Ogert, Robert A.; Burans, James; O'Brien, Tom; Ligler, Frances S.

1994-03-01

The basic recognition schemes underlying the principles of standard enzyme-linked immunosorbent assay (ELISA) and radioimmunoassay (RIA) protocols are increasingly being adapted for use with new detection devices. A direct comparison was made using a fiber optic biosensor that employs evanescent wave detection and an ELISA using avidin-biotin. The assays were developed for the detection of Ricinus communis agglutinin II, also known as ricin or RCA60. Detection limits between the two methods were comparable for ricin in phosphate buffered saline (PBS), however results in complex samples differed slightly. In PBS, sensitivity for ricin was 1 ng/ml using the fiber optic device and 500 pg/ml using the ELISA. The fiber optic sensor could not detect ricin directly in urine or serum spiked with 5 ng/ml ricin, however, the ELISA showed detection but at reduced levels to the PBS control.

Scene text detection via extremal region based double threshold convolutional network classification

PubMed Central

Zhu, Wei; Lou, Jing; Chen, Longtao; Xia, Qingyuan

2017-01-01

In this paper, we present a robust text detection approach in natural images which is based on region proposal mechanism. A powerful low-level detector named saliency enhanced-MSER extended from the widely-used MSER is proposed by incorporating saliency detection methods, which ensures a high recall rate. Given a natural image, character candidates are extracted from three channels in a perception-based illumination invariant color space by saliency-enhanced MSER algorithm. A discriminative convolutional neural network (CNN) is jointly trained with multi-level information including pixel-level and character-level information as character candidate classifier. Each image patch is classified as strong text, weak text and non-text by double threshold filtering instead of conventional one-step classification, leveraging confident scores obtained via CNN. To further prune non-text regions, we develop a recursive neighborhood search algorithm to track credible texts from weak text set. Finally, characters are grouped into text lines using heuristic features such as spatial location, size, color, and stroke width. We compare our approach with several state-of-the-art methods, and experiments show that our method achieves competitive performance on public datasets ICDAR 2011 and ICDAR 2013. PMID:28820891

Feasibility of Tracking Fish with Acoustic Transmitters in the Ice Harbor Dam Tailrace

PubMed Central

Ingraham, John M.; Deng, Z. Daniel; Martinez, Jayson J.; Trumbo, Bradly A.; Mueller, Robert P.; Weiland, Mark A.

2014-01-01

The Juvenile Salmon Acoustic Telemetry System (JSATS) has been used at many dams but has never been deployed in the near-dam tailrace environment. The use of JSATS in the tailrace is of interest to fishery managers to evaluate downstream passage behavior of juvenile salmonids and dam approach behavior of upstream migrating adult salmon and lamprey. The acoustic noise level and detection range of JSATS were studied to determine the feasibility of deploying JSATS in the Ice Harbor Dam tailrace. The noise level measured from the powerhouse deck was less than 104 dB re 1 μPa except for the turbine outlet near the spillway, and 350 m downstream of the dam, the noise level was less than 106 dB. The measured noise levels would allow a theoretical detection range of 100 m to 350 m and 85 m to 320 m, respectively. Validation experiments showed that the detection range is 113 to 184 m using hydrophones deployed from the powerhouse deck and 148 m using hydrophones deployed 500 m downstream of the dam. PMID:24522516

Detection of geometric phases in superconducting nanocircuits

PubMed

Falci; Fazio; Palma; Siewert; Vedral

2000-09-21

When a quantum-mechanical system undergoes an adiabatic cyclic evolution, it acquires a geometrical phase factor' in addition to the dynamical one; this effect has been demonstrated in a variety of microscopic systems. Advances in nanotechnology should enable the laws of quantum dynamics to be tested at the macroscopic level, by providing controllable artificial two-level systems (for example, in quantum dots and superconducting devices). Here we propose an experimental method to detect geometric phases in a superconducting device. The setup is a Josephson junction nanocircuit consisting of a superconducting electron box. We discuss how interferometry based on geometrical phases may be realized, and show how the effect may be applied to the design of gates for quantum computation.

A massive experiment on choice blindness in political decisions: Confidence, confabulation, and unconscious detection of self-deception

PubMed Central

Rieznik, Andrés; Moscovich, Lorena; Frieiro, Alan; Figini, Julieta; Catalano, Rodrigo; Garrido, Juan Manuel; Álvarez Heduan, Facundo; Sigman, Mariano; Gonzalez, Pablo A.

2017-01-01

We implemented a Choice Blindness Paradigm containing political statements in Argentina to reveal the existence of categorical ranges of introspective reports, identified by confidence and agreement levels, separating easy from very hard to manipulate decisions. CBP was implemented in both live and web-based forms. Importantly, and contrary to what was observed in Sweden, we did not observe changes in voting intentions. Also, confidence levels in the manipulated replies where significantly lower than in non-manipulated cases even in undetected manipulations. We name this phenomenon unconscious detection of self-deception. Results also show that females are more difficult to manipulate than men. PMID:28196093

DETECTION OF KOI-13.01 USING THE PHOTOMETRIC ORBIT

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

Shporer, Avi; Jenkins, Jon M.; Seader, Shawn E.

2011-12-15

We use the KOI-13 transiting star-planet system as a test case for the recently developed BEER algorithm, aimed at identifying non-transiting low-mass companions by detecting the photometric variability induced by the companion along its orbit. Such photometric variability is generated by three mechanisms: the beaming effect, tidal ellipsoidal distortion, and reflection/heating. We use data from three Kepler quarters, from the first year of the mission, while ignoring measurements within the transit and occultation, and show that the planet's ephemeris is clearly detected. We fit for the amplitude of each of the three effects and use the beaming effect amplitude tomore » estimate the planet's minimum mass, which results in M{sub p} sin i = 9.2 {+-} 1.1 M{sub J} (assuming the host star parameters derived by Szabo et al.). Our results show that non-transiting star-planet systems similar to KOI-13.01 can be detected in Kepler data, including a measurement of the orbital ephemeris and the planet's minimum mass. Moreover, we derive a realistic estimate of the amplitudes uncertainties, and use it to show that data obtained during the entire lifetime of the Kepler mission of 3.5 years will allow detecting non-transiting close-in low-mass companions orbiting bright stars, down to the few Jupiter mass level. Data from the Kepler Extended Mission, if funded by NASA, will further improve the detection capabilities.« less

Low-noise mid-IR upconversion detector for improved IR-degenerate four-wave mixing gas sensing.

PubMed

Høgstedt, Lasse; Dam, Jeppe Seidelin; Sahlberg, Anna-Lena; Li, Zhongshan; Aldén, Marcus; Pedersen, Christian; Tidemand-Lichtenberg, Peter

2014-09-15

We compare a nonlinear upconversion detector with a conventional cryogenic InSb detector for the detection of coherent infrared light showing near-shot-noise-limited performance in the upconversion system. The InSb detector is limited by dark noise, which results in a 500 times lower signal-to-noise ratio. The two detectors are compared for the detection of a coherent degenerate four-wave mixing (DFWM) signal in the mid-infrared, and applied to measure trace-level acetylene in a gas flow at atmospheric pressure, probing its fundamental rovibrational transitions. In addition to lower noise, the upconversion system provides image information of the signal, thus adding new functionality compared to standard point detection methods. We further show that the upconversion detector system can be implemented as a simple replacement of the cryogenic detector.

Sers Imaging of Nasopharyngeal Carcinoma Markers Using an Antibody-Conjugated Gold Nanoparticles Probe

NASA Astrophysics Data System (ADS)

Li, J.-H.; Du, Y.; Feng, G.-K.; Du, Y.-B.; Zhou, Y.-Q.; Zeng, M.-S.

2017-11-01

Surface-enhanced Raman scattering (SERS) nanotags as an ultrasensitive nanoprobe is becoming popular for the detection of biomarkers. Herein, antibody-conjugated gold nanoparticles (AuNPs) were used to target LMP2A in an LMP2A-infected CNE2 cell line. SERS maps showed that the LMP2A was distributed around the cell, which was consistent with the results of immunofl uorescence staining in the previous report. This location could be due to the specific binding of the bioconjugated nanotags to the receptors on the cell surface. However, the CNE2 cell line without LMP2A-infected showed no detectable signal at 1044 cm-1. The results demonstrated the potential feasibility of AuNPs nanotags as highly sensitive probes conjugated at the subcellular level for detection and localization of cancer markers in nasopharyngeal carcinoma (NPC).

Screening for hemochromatosis by measuring ferritin levels: a more effective approach

PubMed Central

Waalen, Jill; Felitti, Vincent J.; Gelbart, Terri

2008-01-01

Because the penetrance of HFE hemochromatosis is low, traditional population screening measuring the transferrin saturation is unlikely to be cost-effective because the majority of subjects detected neither have clinical disease nor are likely to develop it. Three independent studies show that only patients with serum ferritin concentrations more than 1000 μg/L are at risk for cirrhosis, one of the main morbidities of hemochromatosis. Among 29 699 white subjects participating in the Scripps/Kaiser hemochromatosis study, only 59 had serum ferritin levels more than 1000 μg/L; 24 had homozygous mutant or compound heterozygous mutant HFE genotypes. In all but 5 of the other subjects, the causes of elevated ferritin were excessive alcohol intake, cancer, or liver disease. Screening for hemochromatosis with serum ferritin levels will detect the majority of patients who will be clinically affected and may detect other clinically significant disease in patients who do not have hemochromatosis genotypes. Because the ferritin level of the majority of adult homozygotes for HFE mutations does not rise over long periods of time, excluding subjects with serum ferritin levels less than or equal to 1000 μg/L should not result in missed opportunities for early treatment of patients who could benefit. PMID:18025154

Prevalence of hepatitis A viral RNA and antibodies among Chinese blood donors.

PubMed

Sun, P; Su, N; Lin, F Z; Ma, L; Wang, H J; Rong, X; Dai, Y D; Li, J; Jian, Z W; Tang, L H; Xiao, W; Li, C Q

2015-12-09

Like other developing countries, China was reported to have a relatively high seroprevalence of anti-hepatitis A antibodies (anti-HAV). However, no studies have evaluated the prevalence of anti-HAV and HAV RNA among voluntary blood donors with or without elevated serum alanine transaminase (ALT) levels. Anti-HAV antibodies were detected using an enzyme-linked immunosorbent assay, and reverse transcription quantitative polymerase chain reaction was carried out for detection of HAV RNA. In the current study, we analyzed a total of 450 serum samples with elevated ALT levels (≥40 U/L) and 278 serum samples with non-elevated ALT levels. Seroprevalence rates of anti-HAV were 51.6% in donors with elevated ALT and 41.4% in donors with non-elevated ALT; however, none of the samples was positive for HAV RNA. The results of our study showed lower seroprevalence rates of anti-HAV in blood donors (irrespective of ALT levels) than those in published data on Chinese populations. Although donors with elevated ALT had statistically higher prevalence rates of anti- HAV than did those with non-elevated ALT, none of the serum samples had detectable levels of the active virus. In conclusion, our results demonstrate that the transmission of hepatitis A by blood transfusion will occur rarely.

A Novel Event-Based Incipient Slip Detection Using Dynamic Active-Pixel Vision Sensor (DAVIS)

PubMed Central

Rigi, Amin

2018-01-01

In this paper, a novel approach to detect incipient slip based on the contact area between a transparent silicone medium and different objects using a neuromorphic event-based vision sensor (DAVIS) is proposed. Event-based algorithms are developed to detect incipient slip, slip, stress distribution and object vibration. Thirty-seven experiments were performed on five objects with different sizes, shapes, materials and weights to compare precision and response time of the proposed approach. The proposed approach is validated by using a high speed constitutional camera (1000 FPS). The results indicate that the sensor can detect incipient slippage with an average of 44.1 ms latency in unstructured environment for various objects. It is worth mentioning that the experiments were conducted in an uncontrolled experimental environment, therefore adding high noise levels that affected results significantly. However, eleven of the experiments had a detection latency below 10 ms which shows the capability of this method. The results are very promising and show a high potential of the sensor being used for manipulation applications especially in dynamic environments. PMID:29364190

System-level protection and hardware Trojan detection using weighted voting.

PubMed

Amin, Hany A M; Alkabani, Yousra; Selim, Gamal M I

2014-07-01

The problem of hardware Trojans is becoming more serious especially with the widespread of fabless design houses and design reuse. Hardware Trojans can be embedded on chip during manufacturing or in third party intellectual property cores (IPs) during the design process. Recent research is performed to detect Trojans embedded at manufacturing time by comparing the suspected chip with a golden chip that is fully trusted. However, Trojan detection in third party IP cores is more challenging than other logic modules especially that there is no golden chip. This paper proposes a new methodology to detect/prevent hardware Trojans in third party IP cores. The method works by gradually building trust in suspected IP cores by comparing the outputs of different untrusted implementations of the same IP core. Simulation results show that our method achieves higher probability of Trojan detection over a naive implementation of simple voting on the output of different IP cores. In addition, experimental results show that the proposed method requires less hardware overhead when compared with a simple voting technique achieving the same degree of security.

Monitoring of perchlorate in diverse foods and its estimated dietary exposure for Korea populations.

PubMed

Lee, Ji-Woo; Oh, Sung-Hee; Oh, Jeong-Eun

2012-12-01

The perchlorate concentrations in various Korean food samples were monitored, and 663 samples belonging to 39 kinds of food were analyzed. The analysis results revealed that dairy products contain the highest average concentration of 6.34 μg/kg and high detection frequency of over 85%. Fruit and vegetables showed the next highest perchlorate concentration with an average of 6.17 μg/kg. Especially, with its average concentration of 39.9 μg/kg, spinach showed the highest perchlorate level among all target food samples studied. Tomato was followed by spinach, which showed a high perchlorate average concentration of 19.8 μg/kg, and over 7 μg/kg was detected in ham and sausage (avg. 7.31 μg/kg) and in instant noodles (avg. 7.58 μg/kg). Less than 2 μg/kg was detected in fishes, meats and beverages. The exposure dose of perchlorate in Korean by food intake was calculated on the basis of the analyzed perchlorate levels in this study. The daily perchlorate dose to which Korean adults are exposed is 0.04 μg/kg bw/day, which is lower than the RfD (0.7 μg/kg bw/day) value suggested by US NAS. This result indicates that Korean people's current exposure to perchlorate from domestic food consumption is evaluated as safe. Copyright © 2012 Elsevier B.V. All rights reserved.

Comparison of Three Different Commercial Kits for the Human Papilloma Virus Genotyping.

PubMed

Lim, Yong Kwan; Choi, Jee-Hye; Park, Serah; Kweon, Oh Joo; Park, Ae Ja

2016-11-01

High-risk type human papilloma virus (HPV) is the most important cause of cervical cancer. Recently, real-time polymerase chain reaction and reverse blot hybridization assay-based HPV DNA genotyping kits are developed. So, we compared the performances of different three HPV genotyping kits using different analytical principles and methods. Two hundred positive and 100 negative cervical swab specimens were used. DNA was extracted and all samples were tested by the MolecuTech REBA HPV-ID, Anyplex II HPV28 Detection, and HPVDNAChip. Direct sequencing was performed as a reference method for confirming high-risk HPV genotypes 16, 18, 45, 52, and 58. Although high-level agreement results were observed in negative samples, three kits showed decreased interassay agreement as screening setting in positive samples. Comparing the genotyping results, three assays showed acceptable sensitivity and specificity for the detection of HPV 16 and 18. Otherwise, various sensitivities showed in the detection of HPV 45, 52, and 58. The three assays had dissimilar performance of HPV screening capacity and exhibited moderate level of concordance in HPV genotyping. These discrepant results were unavoidable due to difference in type-specific analytical sensitivity and lack of standardization; therefore, we suggested that the efforts to standardization of HPV genotyping kits and adjusting analytical sensitivity would be important for the best clinical performance. © 2016 Wiley Periodicals, Inc.

Allelic and Epitopic Characterization of Intra-Kidney Allograft Anti-HLA Antibodies at Allograft Nephrectomy.

PubMed

Milongo, D; Kamar, N; Del Bello, A; Guilbeau-Frugier, C; Sallusto, F; Esposito, L; Dörr, G; Blancher, A; Congy-Jolivet, N

2017-02-01

The reasons for the increased incidence of de novo anti-human leukocyte antibody (HLA) donor-specific antibodies (DSAs) observed after kidney allograft nephrectomy are not fully understood. One advocated mechanism suggests that at graft loss, DSAs are not detected in the serum because they are fixed on the nonfunctional transplant; removal of the kidney allows DSAs to then appear in the blood circulation. The aim of our study was to compare anti-HLA antibodies present in the serum and in the graft at the time of an allograft nephrectomy. Using solid-phase assays, anti-HLA antibodies were searched for in the sera of 17 kidney transplant patients undergoing allograft nephrectomy. No anti-HLA antibodies were detected in the graft if they were not also detected in the serum. Eleven of the 12 patients who had DSAs detected in their sera also had DSAs detected in the grafts. Epitopic analysis revealed that most anti-HLA antibodies detected in removed grafts were directed against the donor. In summary, our data show that all anti-HLA antibodies that were detected in grafts were also detected in the sera. These intragraft anti-HLA antibodies are mostly directed against the donor at an epitopic level but not always at an antigenic level. © Copyright 2016 The American Society of Transplantation and the American Society of Transplant Surgeons.

Neighbor detection at the leaf tip adaptively regulates upward leaf movement through spatial auxin dynamics

PubMed Central

Reinen, Emilie; Anten, Niels P. R.

2017-01-01

Vegetation stands have a heterogeneous distribution of light quality, including the red/far-red light ratio (R/FR) that informs plants about proximity of neighbors. Adequate responses to changes in R/FR are important for competitive success. How the detection and response to R/FR are spatially linked and how this spatial coordination between detection and response affects plant performance remains unresolved. We show in Arabidopsis thaliana and Brassica nigra that localized FR enrichment at the lamina tip induces upward leaf movement (hyponasty) from the petiole base. Using a combination of organ-level transcriptome analysis, molecular reporters, and physiology, we show that PIF-dependent spatial auxin dynamics are key to this remote response to localized FR enrichment. Using computational 3D modeling, we show that remote signaling of R/FR for hyponasty has an adaptive advantage over local signaling in the petiole, because it optimizes the timing of leaf movement in response to neighbors and prevents hyponasty caused by self-shading. PMID:28652357

The simultaneous detection of trivalent & hexavalent chromium in exhaled breath condensate: A feasibility study comparing workers and controls.

PubMed

Leese, Elizabeth; Morton, Jackie; Gardiner, Philip H E; Carolan, Vikki A

2017-04-01

The analytical method outlined in this feasibility study has been used to show that trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)) can be detected and measured in exhaled breath condensate (EBC) samples. EBC samples and urine samples were collected from a cohort of 58 workers occupationally exposed to hexavalent chromium compounds and 22 unexposed volunteers (control group). Levels of Cr(III) and Cr(VI) were determined in EBC samples and total chromium levels were determined in urine samples. Pre and post working week samples for both EBC and urine were collected in tandem. Total chromium in urine samples was analysed by inductively coupled plasma mass spectrometry (ICP-MS). Analysis of Cr(III) and Cr(VI) in EBC samples used a hyphenated micro liquid chromatography (μLC) system coupled to an ICP-MS. Separation was achieved using an anion exchange micro-sized column. The results showed that the occupationally exposed workers had significantly higher levels of Cr(III) and Cr(VI) in their EBC samples than the control group, as well as higher levels of total chromium in their urine samples. However, for the exposed workers no significant difference was found between pre and post working week EBC samples for either Cr(III) or Cr(VI). This study has established that Cr(III) and Cr(VI) can simultaneously be detected and measured in 'real' EBC samples and will help in understanding inhalation exposure. Crown Copyright © 2016. Published by Elsevier GmbH. All rights reserved.

Distinguishing detection from identification in subliminal auditory perception: a review and critique of Merikle's study.

PubMed

Harris, J L; Salus, D; Rerecich, R; Larsen, D

1996-01-01

Assertions made by Merikle (1988) regarding audio subliminal messages were tested. Seventeen participants were presented subliminal messages embedded in a white-noise cover, and three signal-to-noise (S/N) detection ratios were examined. Participants were asked to guess message presence and message content, to determine subjective/objective thresholds. Results showed that participants were unable to identify target words presented in this audio subliminal stimulus format beyond chance levels.

Improvement of statistical methods for detecting anomalies in climate and environmental monitoring systems

NASA Astrophysics Data System (ADS)

Yakunin, A. G.; Hussein, H. M.

2018-01-01

The article shows how the known statistical methods, which are widely used in solving financial problems and a number of other fields of science and technology, can be effectively applied after minor modification for solving such problems in climate and environment monitoring systems, as the detection of anomalies in the form of abrupt changes in signal levels, the occurrence of positive and negative outliers and the violation of the cycle form in periodic processes.

Urinary Concentrations of Triclosan, Benzophenone-3, and Bisphenol A in Taiwanese Children and Adolescents

PubMed Central

Chang, Fu-Kuei; Shiea, Jentaie; Tsai, Hsin-Jen

2017-01-01

The purpose of this study was to determine the levels of urinary triclosan (TCS), benzophenone-3 (BP-3), and bisphenol A (BPA) in 52 children and 71 adolescents. The effects of age and sex on the levels of urinary TCS, BP-3, and BPA were explored, respectively. Results demonstrated the overall detection rates of urinary TCS, BP-3, and BPA were 18.7%, 8.1%, and 49.6%, respectively. The females had higher TCS concentrations than males (p = 0.051). The detection rate of urinary BP-3 in females (12.3%) was higher than that in males (0%) (p = 0.015). Moreover, the detection rate of urinary BP-3 in adolescents (14.1%) was higher than that in children (0%) (p = 0.005). For children, no urinary BP-3 was found. There were no differences in detection rates and concentrations of urinary TCS, BP-3, and BPA between males and females, respectively. For adolescents, urinary BP-3 was only found in the females. Urinary TCS levels in females were higher than those in males (p = 0.047). The present study showed that urinary TCS concentrations in females were significantly higher than those in males, respectively. In addition, BP-3 was only detected in urine samples of female adolescents. Sex and age were the important factors influencing urinary TCS and BP-3 concentrations. PMID:29232866

Breath analysis based on micropreconcentrator for early cancer diagnosis

NASA Astrophysics Data System (ADS)

Lee, Sang-Seok

2018-02-01

We are developing micropreconcentrators based on micro/nanotechnology to detect trace levels of volatile organic compound (VOC) gases contained in human and canine exhaled breath. The possibility of using exhaled VOC gases as biomarkers for various cancer diagnoses has been previously discussed. For early cancer diagnosis, detection of trace levels of VOC gas is indispensable. Using micropreconcentrators based on MEMS technology or nanotechnology is very promising for detection of VOC gas. A micropreconcentrator based breath analysis technique also has advantages from the viewpoints of cost performance and availability for various cancers diagnosis. In this paper, we introduce design, fabrication and evaluation results of our MEMS and nanotechnology based micropreconcentrators. In the MEMS based device, we propose a flower leaf type Si microstructure, and its shape and configuration are optimized quantitatively by finite element method simulation. The nanotechnology based micropreconcentrator consists of carbon nanotube (CNT) structures. As a result, we achieve ppb level VOC gas detection with our micropreconcentrators and usual gas chromatography system that can detect on the order of ppm VOC in gas samples. In performance evaluation, we also confirm that the CNT based micropreconcentrator shows 115 times better concentration ratio than that of the Si based micropreconcentrator. Moreover, we discuss a commercialization idea for new cancer diagnosis using breath analysis. Future work and preliminary clinical testing in dogs is also discussed.

Simultaneous detection of pH changes and histamine release from oxyntic glands in isolated stomach.

PubMed

Bitziou, Eleni; O'Hare, Danny; Patel, Bhavik Anil

2008-11-15

Real-time simultaneous detection of changes in pH and levels of histamine over the oxyntic glands of guinea pig stomach have been investigated. An iridium oxide pH microelectrode was used in a potentiometric mode to record the pH decrease associated with acid secretion when the sensor approached the isolated tissue. A boron-doped diamond (BDD) microelectrode was used in an amperometric mode to detect histamine when the electrode was placed over the tissue. Both sensors provided stable and reproducible responses that were qualitatively consistent with the signaling mechanism for acid secretion at the stomach. Simultaneous measurements in the presence of pharmacological treatments produced significant variations in the signals obtained by both sensors. As the H2 receptor antagonist cimetidine was perfused to the tissue, histamine levels increased that produced an increase in the signal of the BDD electrode whereas the pH sensor recorded a decrease in acid secretion as expected. Addition of acetylcholine (ACh) stimulated additional acid secretion detected with the pH microelectrode whereas the BDD sensor recorded the histamine levels decreasing significantly. This result shows that the primary influence of ACh is directly on the parietal cell receptors rather then the ECL cell receptors of the oxyntic glands. These results highlight the power of this simultaneous detection technique in the monitoring and diagnosis of physiological significant signaling mechanisms and pathways.

Most Probable Number Rapid Viability PCR Method to Detect Viable Spores of Bacillus anthracis in Swab Samples

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

Letant, S E; Kane, S R; Murphy, G A

2008-05-30

This note presents a comparison of Most-Probable-Number Rapid Viability (MPN-RV) PCR and traditional culture methods for the quantification of Bacillus anthracis Sterne spores in macrofoam swabs generated by the Centers for Disease Control and Prevention (CDC) for a multi-center validation study aimed at testing environmental swab processing methods for recovery, detection, and quantification of viable B. anthracis spores from surfaces. Results show that spore numbers provided by the MPN RV-PCR method were in statistical agreement with the CDC conventional culture method for all three levels of spores tested (10{sup 4}, 10{sup 2}, and 10 spores) even in the presence ofmore » dirt. In addition to detecting low levels of spores in environmental conditions, the MPN RV-PCR method is specific, and compatible with automated high-throughput sample processing and analysis protocols.« less

A method for detecting nonlinear determinism in normal and epileptic brain EEG signals.

PubMed

Meghdadi, Amir H; Fazel-Rezai, Reza; Aghakhani, Yahya

2007-01-01

A robust method of detecting determinism for short time series is proposed and applied to both healthy and epileptic EEG signals. The method provides a robust measure of determinism through characterizing the trajectories of the signal components which are obtained through singular value decomposition. Robustness of the method is shown by calculating proposed index of determinism at different levels of white and colored noise added to a simulated chaotic signal. The method is shown to be able to detect determinism at considerably high levels of additive noise. The method is then applied to both intracranial and scalp EEG recordings collected in different data sets for healthy and epileptic brain signals. The results show that for all of the studied EEG data sets there is enough evidence of determinism. The determinism is more significant for intracranial EEG recordings particularly during seizure activity.

High-Level Data Races

NASA Technical Reports Server (NTRS)

Artho, Cyrille; Havelund, Klaus; Biere, Armin; Koga, Dennis (Technical Monitor)

2003-01-01

Data races are a common problem in concurrent and multi-threaded programming. They are hard to detect without proper tool support. Despite the successful application of these tools, experience shows that the notion of data race is not powerful enough to capture certain types of inconsistencies occurring in practice. In this paper we investigate data races on a higher abstraction layer. This enables us to detect inconsistent uses of shared variables, even if no classical race condition occurs. For example, a data structure representing a coordinate pair may have to be treated atomically. By lifting the meaning of a data race to a higher level, such problems can now be covered. The paper defines the concepts view and view consistency to give a notation for this novel kind of property. It describes what kinds of errors can be detected with this new definition, and where its limitations are. It also gives a formal guideline for using data structures in a multi-threading environment.

A flexural crack model for damage detection in reinforced concrete structures

NASA Astrophysics Data System (ADS)

Hamad, W. I.; Owen, J. S.; Hussein, M. F. M.

2011-07-01

The use of changes in vibration data for damage detection of reinforced concrete structures faces many challenges that obstruct its transition from a research topic to field applications. Among these is the lack of appropriate damage models that can be deployed in the damage detection methods. In this paper, a model of a simply supported reinforced concrete beam with multiple cracks is developed to examine its use for damage detection and structural health monitoring. The cracks are simulated by a model that accounts for crack formation, propagation and closure. The beam model is studied under different dynamic excitations, including sine sweep and single excitation frequency, for various damage levels. The changes in resonant frequency with increasing loads are examined along with the nonlinear vibration characteristics. The model demonstrates that the resonant frequency reduces by about 10% at the application of 30% of the ultimate load and then drops gradually by about 25% at 70% of the ultimate load. The model also illustrates some nonlinearity in the dynamic response of damaged beams. The appearance of super-harmonics shows that the nonlinearity is higher when the damage level is about 35% and then decreases with increasing damage. The restoring force-displacement relationship predicted the reduction in the overall stiffness of the damaged beam. The model quantitatively predicts the experimental vibration behaviour of damaged RC beams and also shows the damage dependency of nonlinear vibration behaviour.

A novel interdigitated capacitor based biosensor for detection of cardiovascular risk marker.

PubMed

Quershi, Anjum; Gurbuz, Yasar; Kang, Weng P; Davidson, Jimmy L

2009-12-15

C-reactive protein (CRP) is a potential biomarker whose elevated levels in humans determine cardiovascular disease risk and inflammation. In this study, we have developed a novel capacitive biosensor for detection of CRP-antigen using capacitor with interdigitated gold (GID) electrodes on nanocrystalline diamond (NCD) surface. The NCD surface served as a dielectric layer between the gold electrodes. GID-surface was functionalized by antibodies and the immobilization was confirmed by Fourier transform spectroscopy (FT-IR) and contact angle measurements. The CRP-antigen detection was performed by capacitive/dielectric-constant measurements. The relaxation time and polarizability constants were estimated using Cole-Cole model. Our results showed that the relaxation time constant (tau) of only CRP-antibody was within 10(-16)-10(-13)s, which was increased to 10(-11)s after the incubation with CRP-antigen, suggesting that the CRP-antigen was captured by the antibodies on GID-surface. In addition, polarizability constant (m) of CRP was also increased upon incubation with increasing concentration of CRP-antigen. Our results showed that the response of GID-NCD-based capacitive biosensor for CRP-antigen was dependent on both concentration (25-800ng/ml) as well as frequency (50-350MHz). Furthermore, using optimized conditions, the GID-NCD based capacitive biosensor developed in this study can potentially be used for detection of elevated levels of protein risk markers in suspected subjects for early diagnosis of disease.

Tracking wakefulness as it fades: Micro-measures of alertness.

PubMed

Jagannathan, Sridhar R; Ezquerro-Nassar, Alejandro; Jachs, Barbara; Pustovaya, Olga V; Bareham, Corinne A; Bekinschtein, Tristan A

2018-08-01

A major problem in psychology and physiology experiments is drowsiness: around a third of participants show decreased wakefulness despite being instructed to stay alert. In some non-visual experiments participants keep their eyes closed throughout the task, thus promoting the occurrence of such periods of varying alertness. These wakefulness changes contribute to systematic noise in data and measures of interest. To account for this omnipresent problem in data acquisition we defined criteria and code to allow researchers to detect and control for varying alertness in electroencephalography (EEG) experiments under eyes-closed settings. We first revise a visual-scoring method developed for detection and characterization of the sleep-onset process, and adapt the same for detection of alertness levels. Furthermore, we show the major issues preventing the practical use of this method, and overcome these issues by developing an automated method (micro-measures algorithm) based on frequency and sleep graphoelements, which are capable of detecting micro variations in alertness. The validity of the micro-measures algorithm was verified by training and testing using a dataset where participants are known to fall asleep. In addition, we tested generalisability by independent validation on another dataset. The methods developed constitute a unique tool to assess micro variations in levels of alertness and control trial-by-trial retrospectively or prospectively in every experiment performed with EEG in cognitive neuroscience under eyes-closed settings. Copyright © 2018. Published by Elsevier Inc.

Research on the preparation, uniformity and stability of mixed standard substance for rapid detection of goat milk composition.

PubMed

Zhu, Yuying; Wang, Jianmin; Wang, Cunfang

2018-05-01

Taking fresh goat milk as raw material after filtering, centrifuging, hollow fiber ultrafiltration, allocating formula, value detection and preparation processing, a set of 10 goat milk mixed standard substances was prepared on the basis of one-factor-at-a-time using a uniform design method, and its accuracy, uniformity and stability were evaluated by paired t-test and F-test of one-way analysis of variance. The results showed that three milk composition contents of these standard products were independent of each other, and the preparation using the quasi-level design method, and without emulsifier was the best program. Compared with detection value by cow milk standards for calibration fast analyzer, the calibration by goat milk mixed standard was more applicable to rapid detection of goat milk composition, detection value was more accurate and the deviation showed less error. Single factor analysis of variance showed that the uniformity and stability of the mixed standard substance were better; it could be stored for 15 days at 4°C. The uniformity and stability of the in-units and inter-units could meet the requirements of the preparation of national standard products. © 2018 Japanese Society of Animal Science.

Pregnancy is detected via odour in a wild cooperative breeder.

PubMed

Mitchell, J; Cant, M A; Nichols, H J

2017-11-01

Among mammals, scent has long been known to encode oestrus; however, in many species, detecting pregnancy may also be important in terms of both competition and mate-choice. Here, we show, through odour presentation experiments, that pregnancy is discernible via scent by both sexes in the cooperatively breeding banded mongoose, Mungos mungo Males spent more time investigating and were more likely to scent mark the odours of non-pregnant females, compared to pregnant females. Females showed increased levels of scent marking when odours were of the same reproductive state as themselves. These results present the first direct demonstration that pregnancy is detectable via scent in wild cooperative breeders. Detecting pregnancy may be particularly important in cooperative breeders as, in addition to the competition between males for receptive mates, there is also intense competition between females for access to alloparental care. Consequently, dominant females benefit from targeting reproductive suppression towards subordinates that represent direct threats, such as pregnant females. © 2017 The Author(s).

Screening for cocaine on Euro banknotes by a highly sensitive enzyme immunoassay.

PubMed

Abdelshafi, Nahla A; Panne, Ulrich; Schneider, Rudolf J

2017-04-01

This study focused on quantitative detection of cocaine on Euro banknotes in Germany. A sensitive direct competitive immunoassay was developed and optimized with a limit of detection (LOD) of 5.6ng/L. Exhaustive cocaine extraction by solvent was tested using different methanol concentrations and buffered solutions. Cross-reactivity studies were performed to determine the degree of interference of cocaine metabolites with the immunoassay. Sixty-five Euro banknotes obtained from different districts in Berlin were evaluated. A 100% contamination frequency with cocaine was detected. A comparison between the amount of cocaine extracted by cotton swabbing of one square centimeter of the banknote showed a good correlation for lower contamination levels. This assay showed high sensitivity of detecting pg of cocaine per 1cm 2 of one banknote by swabbing 1cm 2 : 0, 14, and 21pg/cm 2 . Moreover, three notes of different denominations revealed high cocaine concentration; 1.1mg/note, and twice 55µg/note. Copyright © 2017 Elsevier B.V. All rights reserved.

Automatic detection system of shaft part surface defect based on machine vision

NASA Astrophysics Data System (ADS)

Jiang, Lixing; Sun, Kuoyuan; Zhao, Fulai; Hao, Xiangyang

2015-05-01

Surface physical damage detection is an important part of the shaft parts quality inspection and the traditional detecting methods are mostly human eye identification which has many disadvantages such as low efficiency, bad reliability. In order to improve the automation level of the quality detection of shaft parts and establish its relevant industry quality standard, a machine vision inspection system connected with MCU was designed to realize the surface detection of shaft parts. The system adopt the monochrome line-scan digital camera and use the dark-field and forward illumination technology to acquire images with high contrast; the images were segmented to Bi-value images through maximum between-cluster variance method after image filtering and image enhancing algorithms; then the mainly contours were extracted based on the evaluation criterion of the aspect ratio and the area; then calculate the coordinates of the centre of gravity of defects area, namely locating point coordinates; At last, location of the defects area were marked by the coding pen communicated with MCU. Experiment show that no defect was omitted and false alarm error rate was lower than 5%, which showed that the designed system met the demand of shaft part on-line real-time detection.

A new fluorescent enhanced probe based on (E)-9-(2-nitrovinyl)-anthracene for the detection of bisulfite anions and its practical application

NASA Astrophysics Data System (ADS)

Chao, Jianbin; Liu, Yuhong; Zhang, Yan; Zhang, Yongbin; Huo, Fangjun; Yin, Caixia; Wang, Yu; Qin, Liping

2015-07-01

A new fluorescent enhanced probe based on (E)-9-(2-nitrovinyl)-anthracene is developed, which shows high selectivity and sensitivity for the detection of bisulfite anions at Na2HPO4 citric acid buffer solutions (pH 5.0). When addition of HSO3-, the fluorescence intensity is significantly enhanced and the probe displays apparent fluorescence color changes from non-fluorescence to blue under a UV lamp illumination, the solution color also changes from yellow to colorless. The detection limit is determined to be as low as 6.30 μM. This offers another specific colorimetric and fluorescent probe for bisulfite anions detection, furthermore it is applied in detecting the level of bisulfite in sugar samples.

A SPITZER SURVEY OF MID-INFRARED MOLECULAR EMISSION FROM PROTOPLANETARY DISKS. I. DETECTION RATES

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

Pontoppidan, Klaus M.; Blake, Geoffrey A.; Meijerink, Rowin

2010-09-01

We present a Spitzer InfraRed Spectrometer search for 10-36 {mu}m molecular emission from a large sample of protoplanetary disks, including lines from H{sub 2}O, OH, C{sub 2}H{sub 2}, HCN, and CO{sub 2}. This paper describes the sample and data processing and derives the detection rate of mid-infrared molecular emission as a function of stellar mass. The sample covers a range of spectral type from early M to A, and is supplemented by archival spectra of disks around A and B stars. It is drawn from a variety of nearby star-forming regions, including Ophiuchus, Lupus, and Chamaeleon. Spectra showing strong emissionmore » lines are used to identify which lines are the best tracers of various physical and chemical conditions within the disks. In total, we identify 22 T Tauri stars with strong mid-infrared H{sub 2}O emission. Integrated water line luminosities, where water vapor is detected, range from 5 x 10{sup -4} to 9 x 10{sup -3} L{sub sun}, likely making water the dominant line coolant of inner disk surfaces in classical T Tauri stars. None of the five transitional disks in the sample show detectable gaseous molecular emission with Spitzer upper limits at the 1% level in terms of line-to-continuum ratios (apart from H{sub 2}), but the sample is too small to conclude whether this is a general property of transitional disks. We find a strong dependence on detection rate with spectral type; no disks around our sample of 25 A and B stars were found to exhibit water emission, down to 1%-2% line-to-continuum ratios, in the mid-infrared, while more than half of disks around late-type stars (M-G) show sufficiently intense water emission to be detected by Spitzer, with a detection rate approaching 2/3 for disks around K stars. Some Herbig Ae/Be stars show tentative H{sub 2}O/OH emission features beyond 20 {mu}m at the 1%-2% level, however, and one of them shows CO{sub 2} in emission. We argue that the observed differences between T Tauri disks and Herbig Ae/Be disks are due to a difference in excitation and/or chemistry depending on spectral type and suggest that photochemistry may be playing an important role in the observable characteristics of mid-infrared molecular line emission from protoplanetary disks.« less

Comparison of 68Ga-labelled PSMA-11 and 11C-choline in the detection of prostate cancer metastases by PET/CT.

PubMed

Schwenck, Johannes; Rempp, Hansjoerg; Reischl, Gerald; Kruck, Stephan; Stenzl, Arnulf; Nikolaou, Konstantin; Pfannenberg, Christina; la Fougère, Christian

2017-01-01

Prostate-specific membrane antigen (PSMA) is expressed ubiquitously on the membrane of most prostate tumors and its metastasis. While PET/CT using 11 C-choline was considered as the gold standard in the staging of prostate cancer, PET with radiolabelled PSMA ligands was introduced into the clinic in recent years. Our aim was to compare the PSMA ligand 68 Ga-PSMA-11 with 11 C-choline in patients with primary and recurrent prostate cancer. 123 patients underwent a whole-body PET/CT examination using 68 Ga-PSMA-11 and 11 C-choline. Suspicious lesions were evaluated visually and semiquantitatively (SUVavg). Out of these, 103 suffered from a confirmed biochemical relapse after prostatectomy and/or radiotherapy (mean PSA level of 4.5 ng/ml), while 20 patients underwent primary staging. In 67 patients with biochemical relapse, we detected 458 lymph nodes suspicious for metastasis. PET using 68 Ga-PSMA-11 showed a significantly higher uptake and detection rate than 11 C-choline PET. Also 68 Ga-PSMA-11 PET identified significantly more patients with suspicious lymph nodes as well as affected lymph nodes regions especially at low PSA levels. Bone lesions suspicious for prostate cancer metastasis were revealed in 36 patients' biochemical relapse. Significantly more bone lesions were detected by 68 Ga-PSMA-11, but only 3 patients had only PSMA-positive bone lesions. Nevertheless, we detected also 29 suspicious lymph nodes and 8 bone lesions, which were only positive as per 11 C-choline PET. These findings led to crucial differences in the TNM classification and the identification of oligometastatic patients. In the patients who underwent initial staging, all primary tumors showed uptake of both tracers. Although significantly more suspicious lymph nodes and bone lesions were identified, only 2 patients presented with bone lesions only detected by 68 Ga-PSMA-11 PET. Thus, PET using 68 Ga-PSMA-11 showed a higher detection rate than 11 C-choline PET for lymph nodes as well as bone lesions. However, we found lymph nodes and bone lesions which were not concordant applying both tracers.

Levels of Polycyclic Aromatic Hydrocarbons, Polychlorinated Biphenyls, and Organochlorine Pesticides in Various Tissues of White-Backed Vulture in India

PubMed Central

Dhananjayan, V.; Muralidharan, S.

2013-01-01

This study provides information on the current status of contamination by polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) in the tissues of endangered White-backed Vulture Gyps bengalensis in India. Chemical analyses revealed detectable amounts of PAHs, PCBs, and OCPs. Concentration ranges of ∑PAHs, ∑PCBs, and ∑OCPs in tissues were 60–2037 ng/g, 30–5790 ng/g, and 3.2–5836 ng/g wet weight, respectively. 1,1-Dichloro-2,2-bis(p-chlorophenyl)ethylene (p,p′-DDE) concentrations ranged from below detectable level to 599 ng/g wet weight, representing more than 90% of the total dichlorodiphenyltrichloroethane (DDT). Among the various OCPs analyzed, p,p′-DDE was detected most frequently. All the contaminants recorded show higher accumulation in liver than other tissues. Levels of contaminants measured in the tissues of vulture are comparable with the levels documented in a number of avian species and are lower than those reported to have caused deleterious effects. Although no threat is expected from the current level of contamination, the presence of varying levels of contaminants and their additive or synergistic toxicity is a cause of concern to vultures. Values reported in this study can serve as guideline for future research. PMID:24288666

Sampling and Pooling Methods for Capturing Herd Level Antibiotic Resistance in Swine Feces using qPCR and CFU Approaches

PubMed Central

Mellerup, Anders; Ståhl, Marie

2015-01-01

The aim of this article was to define the sampling level and method combination that captures antibiotic resistance at pig herd level utilizing qPCR antibiotic resistance gene quantification and culture-based quantification of antibiotic resistant coliform indicator bacteria. Fourteen qPCR assays for commonly detected antibiotic resistance genes were developed, and used to quantify antibiotic resistance genes in total DNA from swine fecal samples that were obtained using different sampling and pooling methods. In parallel, the number of antibiotic resistant coliform indicator bacteria was determined in the same swine fecal samples. The results showed that the qPCR assays were capable of detecting differences in antibiotic resistance levels in individual animals that the coliform bacteria colony forming units (CFU) could not. Also, the qPCR assays more accurately quantified antibiotic resistance genes when comparing individual sampling and pooling methods. qPCR on pooled samples was found to be a good representative for the general resistance level in a pig herd compared to the coliform CFU counts. It had significantly reduced relative standard deviations compared to coliform CFU counts in the same samples, and therefore differences in antibiotic resistance levels between samples were more readily detected. To our knowledge, this is the first study to describe sampling and pooling methods for qPCR quantification of antibiotic resistance genes in total DNA extracted from swine feces. PMID:26114765

Detection and characterization of small hot fires: Comparing FireBird, BIRD, S-NPP VIIRS and MODIS capacities over gas flares

NASA Astrophysics Data System (ADS)

Ruecker, Gernot; Schroeder, Wilfrid; Lorenz, Eckehard; Kaiser, Johannes; Caseiro, Alexandre

2016-04-01

According to recent research, black carbon has the second strongest effect on the earth climate system after carbon dioxide. In high Northern latitudes, industrial gas flares are an important source of black carbon, especially in winter. This fact is particularly relevant for the relatively fast observed climate change in the Arctic since deposition of black carbon changes the albedo of snow and ice, thus leading to a positive feedback cycle. Here we explore gas flare detection and Fire Radiative Power (FRP) retrievals of the German FireBird TET-1 and BIRD Hotspot Recognition Systems (HSRS), the VIIRS sensor on board of the S-NPP satellite, and the MODIS sensor using temporally close to near coincident data acquisitions. Comparison is based on level 2 products developed for fire detection for the different sensors; in the case of S-NPP VIIRS we use two products: the new VIIRS 750m algorithm based on MODIS collection 6, and the 350 m algorithm based on the VIIRS mid-infrared I (Imaging) band, which offers high resolution, but no FRP retrievals. Results indicate that the highest resolution FireBird sensors offer the best detection capacities, though the level two product shows false alarms, followed by the VIIRS 350 m and 750 m algorithms. MODIS has the lowest detection rate. Preliminary results of FRP retrievals show that FireBird and VIIRS algorithms have a good agreement. Given the fact that most gas flaring is at the detection limit for medium to coarse resolution space borne sensors - and hence measurement errors may be high - our results indicates that a quantitative evaluation of gas flaring using these sensors is feasible. Results shall be used to develop a gas flare detection algorithm for Sentinel-3, and a similar methodology will be employed to validate the capacity of Sentinel 3 to detect and characterize small high temperature sources such as gas flares.

The impact of multiple low-level BCR-ABL1 mutations on response to ponatinib.

PubMed

Parker, Wendy T; Yeung, David T O; Yeoman, Alexandra L; Altamura, Haley K; Jamison, Bronte A; Field, Chani R; Hodgson, J Graeme; Lustgarten, Stephanie; Rivera, Victor M; Hughes, Timothy P; Branford, Susan

2016-04-14

The third-generation tyrosine kinase inhibitor (TKI) ponatinib shows activity against all common BCR-ABL1 single mutants, including the highly resistant BCR-ABL1-T315I mutant, improving outcome for patients with refractory chronic myeloid leukemia (CML). However, responses are variable, and causal baseline factors have not been well-studied. The type and number of low-level BCR-ABL1 mutations present after imatinib resistance has prognostic significance for subsequent treatment with nilotinib or dasatinib as second-line therapy. We therefore investigated the impact of low-level mutations detected by sensitive mass-spectrometry before ponatinib initiation (baseline) on treatment response in 363 TKI-resistant patients enrolled in the PONATINIB for Chronic Myeloid Leukemia Evaluation and Ph(+)Acute Lymphoblastic Leukemia trial, including 231 patients in chronic phase (CP-CML). Low-level mutations were detected in 53 patients (15%, including low-level T315I in 14 patients); most, however, did not undergo clonal expansion during ponatinib treatment and, moreover, no specific individual mutations were associated with inferior outcome. We demonstrate however, that the number of mutations detectable by mass spectrometry after TKI resistance is associated with response to ponatinib treatment and could be used to refine the therapeutic approach. Although CP-CML patients with T315I (63/231, 27%) had superior responses overall, those with multiple mutations detectable by mass spectrometry (20, 32%) had substantially inferior responses compared with those with T315I as the sole mutation detected (43, 68%). In contrast, for CP-CML patients without T315I, the inferior responses previously observed with nilotinib/dasatinib therapy for imatinib-resistant patients with multiple mutations were not seen with ponatinib treatment, suggesting that ponatinib may prove to be particularly advantageous for patients with multiple mutations detectable by mass spectrometry after TKI resistance. © 2016 by The American Society of Hematology.

Methyl farnesoate couples environmental changes to testicular development in the crab Carcinus maenas.

PubMed

Nagaraju, G P C; Borst, D W

2008-09-01

Carcinus maenas males have two major color phases. Green-phase males molt frequently and tend to live in brackish estuaries during the summer. After becoming red-phase males, they molt infrequently, have higher mating success, and live in cooler, deeper water. We found profound differences between these two phases in the way salinity and temperature affect hemolymph levels of methyl farnesoate (MF), a hormone that affects crustacean reproduction. Few green-phase males (<10%) had detectable MF in 33 ppt seawater (SW) at 11 or 18 degrees C. By contrast, about 30% of the red-phase males had detectable MF at either temperature. After transfer to 5 ppt SW, none of the green-phase males had detectable MF at 11 degrees C whereas 100% of green-phase males did at 18 degrees C. By contrast, 100% of the red-phase males had detectable MF in 5 ppt SW at either temperature. At 11 degrees C, green-phase males had detectable MF after eyestalk ablation (ESA), showing that they can produce MF. There was no additional increase in MF levels when ESA animals of either color phase were transferred to 5 ppt SW, suggesting that the eyestalk is the primary regulator of the MF response to low salinity. MF levels of green-phase males were increased by injecting MF, by ESA, or by exposure to 5 ppt SW at 18 degrees C. The testicular index of these treated animals nearly doubled after two weeks. Our results strongly suggest that environmental conditions such as temperature and salinity, affect testicular development in this crab by changing its MF levels.

Surface Cleaning Techniques: Ultra-Trace ICP-MS Sample Preparation and Assay of HDPE

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

Overman, Nicole R.; Hoppe, Eric W.; Addleman, Raymond S.

2013-06-01

The world’s most sensitive radiation detection and assay systems depend upon ultra-low background (ULB) materials to reduce unwanted radiological backgrounds. Herein, we evaluate methods to clean HDPE, a material of interest to ULB systems and the means to provide rapid assay of surface and bulk contamination. ULB level material and ultra-trace level detection of actinide elements is difficult to attain, due to the introduction of contamination from sample preparation equipment such as pipette tips, sample vials, forceps, etc. and airborne particulate. To date, literature available on the cleaning of such polymeric materials and equipment for ULB applications and ultra-trace analysesmore » is limited. For these reasons, a study has been performed to identify an effective way to remove surface contamination from polymers in an effort to provide improved instrumental detection limits. Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) was utilized to assess the effectiveness of a variety of leachate solutions for removal of inorganic uranium and thorium surface contamination from polymers, specifically high density polyethylene (HDPE). HDPE leaching procedures were tested to optimize contaminant removal of thorium and uranium. Calibration curves for thorium and uranium ranged from 15 ppq (fg/mL) to 1 ppt (pg/mL). Detection limits were calculated at 6 ppq for uranium and 7 ppq for thorium. Results showed the most effective leaching reagent to be clean 6 M nitric acid for 72 hour exposures. Contamination levels for uranium and thorium found in the leachate solutions were significant for ultralow level radiation detection applications.« less

Usefulness of CA125 and their kinetic parameters and positron emission tomography/computed tomography (PET/CT) with fluorodeoxyglucose ([18F] FDG) in the detection of recurrent ovarian cancer levels.

PubMed

Palomar Muñoz, Azahara; Cordero García, José Manuel; Talavera Rubio, Prado; García Vicente, Ana M; González García, Beatriz; Bellón Guardia, María Emiliana; Soriano Castrejón, Ángel; Aranda Aguilar, Enrique

2017-12-21

To assess the usefulness of cancer antigen 125 (CA125) serum levels and kinetic values, velocity (CA125vel) and doubling time (CA125dt), as well as fluorodeoxyglucose ([ 18 F]FDG) positron emission tomography/computed tomography (PET/CT), in the detection of ovarian cancer recurrence. To assess the optimal cut-off for CA125, CA125vel and CA125dt to detect relapse with [ 18 F]FDG-PET/CT. A retrospective analysis was performed of 59 [ 18 F]FDG-PET/CT (48 patients) for suspected recurrence of ovarian cancer. Receiver operating characteristic (ROC) curves were plotted and area-under-the curve (AUC) statistics were computed for CA125, CA125vel and CA125dt. The results obtained in the group with normal and high (>35U/ml) CA125 levels were compared. Forty-four cases of recurrence were diagnosed (7 had CA125 ≤35U/ml), whereas 15 showed no disease. All of them were correctly catalogued by PET/CT. In ROC analysis, the discriminatory power of CA125 was relatively high (AUC 0.835) and the optimal cut-off point to reflect active disease was 23.9U/ml. The ROC analyses for the CA125vel and CA125dt showed an AUC of 0.849 and 0.728, respectively, with an optimal cut-off point of 1.96U/ml/month and 0.76 months, respectively. In patients with normal CA125 and recurrence of ovarian cancer, the CA125vel was significantly higher than in patients without recurrence (p=0.029). [ 18 F]FDG-PET/CT is more accurate than CA125 parameters in the detection of ovarian cancer recurrence. CA125 serum levels are essential; nevertheless, CA125 kinetic values must be considered to detect relapse. Particularly in patients with CA125 within normal values, in which a higher CA125vel is indicative of recurrence. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

Autonomous rock detection on mars through region contrast

NASA Astrophysics Data System (ADS)

Xiao, Xueming; Cui, Hutao; Yao, Meibao; Tian, Yang

2017-08-01

In this paper, we present a new autonomous rock detection approach through region contrast. Unlike current state-of-art pixel-level rock segmenting methods, new method deals with this issue in region level, which will significantly reduce the computational cost. Image is firstly splitted into homogeneous regions based on intensity information and spatial layout. Considering the high-water memory constraints of onboard flight processor, only low-level features, average intensity and variation of superpixel, are measured. Region contrast is derived as the integration of intensity contrast and smoothness measurement. Rocks are then segmented from the resulting contrast map by an adaptive threshold. Since the merely intensity-based method may cause false detection in background areas with different illuminations from surroundings, a more reliable method is further proposed by introducing spatial factor and background similarity to the region contrast. Spatial factor demonstrates the locality of contrast, while background similarity calculates the probability of each subregion belonging to background. Our method is efficient in dealing with large images and only few parameters are needed. Preliminary experimental results show that our algorithm outperforms edge-based methods in various grayscale rover images.

Remote photoplethysmography system for unsupervised monitoring regional anesthesia effectiveness

NASA Astrophysics Data System (ADS)

Rubins, U.; Miscuks, A.; Marcinkevics, Z.; Lange, M.

2017-12-01

Determining the level of regional anesthesia (RA) is vitally important to both an anesthesiologist and surgeon, also knowing the RA level can protect the patient and reduce the time of surgery. Normally to detect the level of RA, usually a simple subjective (sensitivity test) and complicated quantitative methods (thermography, neuromyography, etc.) are used, but there is not yet a standardized method for objective RA detection and evaluation. In this study, the advanced remote photoplethysmography imaging (rPPG) system for unsupervised monitoring of human palm RA is demonstrated. The rPPG system comprises compact video camera with green optical filter, surgical lamp as a light source and a computer with custom-developed software. The algorithm implemented in Matlab software recognizes the palm and two dermatomes (Medial and Ulnar innervation), calculates the perfusion map and perfusion changes in real-time to detect effect of RA. Seven patients (aged 18-80 years) undergoing hand surgery received peripheral nerve brachial plexus blocks during the measurements. Clinical experiments showed that our rPPG system is able to perform unsupervised monitoring of RA.

Polyfluorinated substances in abiotic standard reference ...

EPA Pesticide Factsheets

The National Institute of Standards and Technology (NIST) has a wide range of Standard Reference Materials (SRMs) which have values assigned for legacy organic pollutants and toxic elements. Existing SRMs serve as homogenous materials that can be used for method development, method validation, and measurement for contaminants that are now of concern. NIST and multiple groups have been measuring the mass fraction of a group of emerging contaminants, polyfluorinated substances (PFASs), in a variety of SRMs. Here we report levels determined in an interlaboratory comparison of up to 23 PFASs determined in five SRMs: sediment (SRMs 1941b and 1944), house dust (SRM 2585), soil (SRM 2586), and sludge (SRM 2781). Measurements presented show an array of PFASs, with perfluorooctane sulfonate being the most frequently detected. SRMs 1941b, 1944, and 2586 had relatively low concentrations of most PFASs measured while 23 PFASs were at detectable levels in SRM 2585 and most of the PFASs measured were at detectable levels in SRM 2781. The measurements made in this study were used to add values to the Certificates of Analysis for SRMs 2585 and 2781. Journal article published in Analytical and Bioanalytical Chemistry

Polyfluorinated substances in abiotic standard reference materials.

PubMed

Reiner, Jessica L; Blaine, Andrea C; Higgins, Christopher P; Huset, Carin; Jenkins, Thomas M; Kwadijk, Christiaan J A F; Lange, Cleston C; Muir, Derek C G; Reagen, William K; Rich, Courtney; Small, Jeff M; Strynar, Mark J; Washington, John W; Yoo, Hoon; Keller, Jennifer M

2015-04-01

The National Institute of Standards and Technology (NIST) has a wide range of Standard Reference Materials (SRMs) which have values assigned for legacy organic pollutants and toxic elements. Existing SRMs serve as homogenous materials that can be used for method development, method validation, and measurement for contaminants that are now of concern. NIST and multiple groups have been measuring the mass fraction of a group of emerging contaminants, polyfluorinated substances (PFASs), in a variety of SRMs. Here we report levels determined in an interlaboratory comparison of up to 23 PFASs determined in five SRMs: sediment (SRMs 1941b and 1944), house dust (SRM 2585), soil (SRM 2586), and sludge (SRM 2781). Measurements presented show an array of PFASs, with perfluorooctane sulfonate being the most frequently detected. SRMs 1941b, 1944, and 2586 had relatively low concentrations of most PFASs measured while 23 PFASs were at detectable levels in SRM 2585 and most of the PFASs measured were at detectable levels in SRM 2781. The measurements made in this study were used to add values to the Certificates of Analysis for SRMs 2585 and 2781.

Sensor data security level estimation scheme for wireless sensor networks.

PubMed

Ramos, Alex; Filho, Raimir Holanda

2015-01-19

Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates.

Sensor Data Security Level Estimation Scheme for Wireless Sensor Networks

PubMed Central

Ramos, Alex; Filho, Raimir Holanda

2015-01-01

Due to their increasing dissemination, wireless sensor networks (WSNs) have become the target of more and more sophisticated attacks, even capable of circumventing both attack detection and prevention mechanisms. This may cause WSN users, who totally trust these security mechanisms, to think that a sensor reading is secure, even when an adversary has corrupted it. For that reason, a scheme capable of estimating the security level (SL) that these mechanisms provide to sensor data is needed, so that users can be aware of the actual security state of this data and can make better decisions on its use. However, existing security estimation schemes proposed for WSNs fully ignore detection mechanisms and analyze solely the security provided by prevention mechanisms. In this context, this work presents the sensor data security estimator (SDSE), a new comprehensive security estimation scheme for WSNs. SDSE is designed for estimating the sensor data security level based on security metrics that analyze both attack prevention and detection mechanisms. In order to validate our proposed scheme, we have carried out extensive simulations that show the high accuracy of SDSE estimates. PMID:25608215

Simultaneous determination of sulfonamides, tetracyclines and tiamulin in swine wastewater by solid-phase extraction and liquid chromatography-mass spectrometry.

PubMed

Ben, Weiwei; Qiang, Zhimin; Adams, Craig; Zhang, Heqing; Chen, Liping

2008-08-22

Little is known about the contamination level of antibiotics in swine wastewater in China. The highly complex matrix of swine wastewater, which generally has a chemical oxygen demand (COD) concentration as high as 15,000 mg/L, makes it difficult to detect antibiotics at trace levels. In this work, a highly selective and sensitive analytical method was developed for simultaneous determination of three classes of commonly used veterinary antibiotics including five sulfonamides, three tetracyclines and one macrolide in swine wastewater using solid-phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS). The method detection limits (MDL) in the swine wastewater were determined to be between 5 and 91 ng/L, depending on specific antibiotics. Except sulfamethizole, all the other eight antibiotics were detected in the swine wastewaters collected from three concentrated swine feeding plants located in the Beijing (China) area, showing a concentration range of 0.62-32.67 microg/L. These results reveal the representative concentration levels of selected antibiotics in the swine wastewaters of Beijing area.

Comparison of human and algorithmic target detection in passive infrared imagery

NASA Astrophysics Data System (ADS)

Weber, Bruce A.; Hutchinson, Meredith

2003-09-01

We have designed an experiment that compares the performance of human observers and a scale-insensitive target detection algorithm that uses pixel level information for the detection of ground targets in passive infrared imagery. The test database contains targets near clutter whose detectability ranged from easy to very difficult. Results indicate that human observers detect more "easy-to-detect" targets, and with far fewer false alarms, than the algorithm. For "difficult-to-detect" targets, human and algorithm detection rates are considerably degraded, and algorithm false alarms excessive. Analysis of detections as a function of observer confidence shows that algorithm confidence attribution does not correspond to human attribution, and does not adequately correlate with correct detections. The best target detection score for any human observer was 84%, as compared to 55% for the algorithm for the same false alarm rate. At 81%, the maximum detection score for the algorithm, the same human observer had 6 false alarms per frame as compared to 29 for the algorithm. Detector ROC curves and observer-confidence analysis benchmarks the algorithm and provides insights into algorithm deficiencies and possible paths to improvement.

Longitudinal Study of Hepatitis A Infection by Saliva Sampling: The Kinetics of HAV Markers in Saliva Revealed the Application of Saliva Tests for Hepatitis A Study.

PubMed

Amado Leon, Luciane Almeida; de Almeida, Adilson José; de Paula, Vanessa Salete; Tourinho, Renata Santos; Villela, Daniel Antunes Maciel; Gaspar, Ana Maria Coimbra; Lewis-Ximenez, Lia Laura; Pinto, Marcelo Alves

2015-01-01

Despite the increasing numbers of studies investigating hepatitis A diagnostic through saliva, the frequency and the pattern of hepatitis A virus (HAV) markers in this fluid still remains unknown. To address this issue, we carried on a longitudinal study to examine the kinetics of HAV markers in saliva, in comparison with serum samples. The present study followed-up ten patients with acute hepatitis A infection during 180 days post diagnosis (dpd). Total anti-HAV was detected in paired serum and saliva samples until the end of the follow-up, showing a peak titer at 90th. However, total anti-HAV level was higher in serum than in saliva samples. This HAV marker showed a probability of 100% to be detected in both serum and saliva during 180 dpd. The IgM anti-HAV could be detected in saliva up to 150 dpd, showing the highest frequency at 30th, when it was detected in all individuals. During the first month of HAV infection, this acute HAV marker showed a detection probability of 100% in paired samples. The detection of IgM anti-HAV in saliva was not dependent on its level in serum, HAV-RNA detection and/or viral load, since no association was found between IgM anti-HAV positivity in saliva and any of these parameter (p>0.05). Most of the patients (80%) were found to contain HAV-RNA in saliva, mainly at early acute phase (30th day). However, it was possible to demonstrate the HAV RNA presence in paired samples for more than 90 days, even after seroconversion. No significant relationship was observed between salivary HAV-RNA positivity and serum viral load, demonstrating that serum viral load is not predictive of HAV-RNA detection in saliva. Similar viral load was seen in paired samples (on average 104 copies/mL). These data demonstrate that the best diagnostic coverage can be achieved by salivary anti-HAV antibodies and HAV-RNA tests during 30-90 dpd. The long detection and high probability of specific-HAV antibodies positivity in saliva samples make the assessment of salivary antibodies a useful tool for diagnosis and epidemiological studies. The high frequency of HAV-RNA in saliva and the probability of detection of about 50%, during the first 30 dpd, demonstrate that saliva is also useful for molecular investigation of hepatitis A cases, mainly during the early course of infection. Therefore, the collection of saliva may provide a simple, cheap and non-invasive means of diagnosis, epidemiological surveys and monitoring of hepatitis A infection purposes.

Longitudinal Study of Hepatitis A Infection by Saliva Sampling: The Kinetics of HAV Markers in Saliva Revealed the Application of Saliva Tests for Hepatitis A Study

PubMed Central

Amado Leon, Luciane Almeida; de Almeida, Adilson José; de Paula, Vanessa Salete; Tourinho, Renata Santos; Villela, Daniel Antunes Maciel; Gaspar, Ana Maria Coimbra; Lewis-Ximenez, Lia Laura; Pinto, Marcelo Alves

2015-01-01

Despite the increasing numbers of studies investigating hepatitis A diagnostic through saliva, the frequency and the pattern of hepatitis A virus (HAV) markers in this fluid still remains unknown. To address this issue, we carried on a longitudinal study to examine the kinetics of HAV markers in saliva, in comparison with serum samples. The present study followed-up ten patients with acute hepatitis A infection during 180 days post diagnosis (dpd). Total anti-HAV was detected in paired serum and saliva samples until the end of the follow-up, showing a peak titer at 90th. However, total anti-HAV level was higher in serum than in saliva samples. This HAV marker showed a probability of 100% to be detected in both serum and saliva during 180 dpd. The IgM anti-HAV could be detected in saliva up to 150 dpd, showing the highest frequency at 30th, when it was detected in all individuals. During the first month of HAV infection, this acute HAV marker showed a detection probability of 100% in paired samples. The detection of IgM anti-HAV in saliva was not dependent on its level in serum, HAV-RNA detection and/or viral load, since no association was found between IgM anti-HAV positivity in saliva and any of these parameter (p>0.05). Most of the patients (80%) were found to contain HAV-RNA in saliva, mainly at early acute phase (30th day). However, it was possible to demonstrate the HAV RNA presence in paired samples for more than 90 days, even after seroconversion. No significant relationship was observed between salivary HAV-RNA positivity and serum viral load, demonstrating that serum viral load is not predictive of HAV-RNA detection in saliva. Similar viral load was seen in paired samples (on average 104 copies/mL). These data demonstrate that the best diagnostic coverage can be achieved by salivary anti-HAV antibodies and HAV-RNA tests during 30–90 dpd. The long detection and high probability of specific-HAV antibodies positivity in saliva samples make the assessment of salivary antibodies a useful tool for diagnosis and epidemiological studies. The high frequency of HAV-RNA in saliva and the probability of detection of about 50%, during the first 30 dpd, demonstrate that saliva is also useful for molecular investigation of hepatitis A cases, mainly during the early course of infection. Therefore, the collection of saliva may provide a simple, cheap and non-invasive means of diagnosis, epidemiological surveys and monitoring of hepatitis A infection purposes. PMID:26690904

Monoamine levels in the nucleus accumbens correlate with male sexual behavior in middle-aged rats.

PubMed

Tsai, Houng-Wei; Shui, Hao-Ai; Liu, Hang-Shen; Tai, Mei-Yun; Tsai, Yuan-Feen

2006-02-01

The correlation between monoamine levels in the nucleus accumbens (NAcc) and male sexual behavior was studied in middle-aged rats. Male rats (18-19months) were assigned to three groups: (1) Group MIE consisted of rats showing mounts, intromissions, and ejaculations; (2) Group MI was composed of rats showing mounts and intromissions, but no ejaculation; and (3) Group NC were non-copulators showing no sexual behavior. Young adult rats (4-5months), displaying complete copulatory behavior, were used as the control group. Levels of dopamine (DA), serotonin, and norepinephrine and their metabolites in the NAcc were measured by high-pressure liquid chromatography with electrochemical detection. No difference was seen in DA levels between MIE rats and young controls, whereas DA levels in NC rats were significantly lower than those in both MIE and MI rats. Serotonin levels in NC rats were significantly higher than those in MIE and MI rats. Conversely, norepinephrine levels in NC rats were lower than those in MIE rats. These results suggest that monoamine levels in the NAcc correlate with sexual performance in male rats and that changes in NAcc monoamine levels might affect male sexual behavior in middle-aged rats.

Diagnostic accuracy of a five-point Likert scoring system for magnetic resonance imaging (MRI) evaluated according to results of MRI/ultrasonography image-fusion targeted biopsy of the prostate.

PubMed

Shin, Toshitaka; Smyth, Thomas B; Ukimura, Osamu; Ahmadi, Nariman; de Castro Abreu, Andre Luis; Ohe, Chisato; Oishi, Masakatsu; Mimata, Hiromitsu; Gill, Inderbir S

2018-01-01

To evaluate the accuracy of a magnetic resonance imaging (MRI)-based Likert scoring system in the detection of clinically significant prostate cancer (CSPC), using MRI/ultrasonography (US) image-fusion targeted biopsy (FTB) as a reference standard. We retrospectively reviewed 1218 MRI-detected lesions in 629 patients who underwent subsequent MRI/US FTB between October 2012 and August 2015. 3-Tesla MRI was independently reported by one of eight radiologists with varying levels of experience and scored on a five-point Likert scale. All lesions with Likert scores 1-5 were prospectively defined as targets for MRI/US FTB. CSPC was defined as Gleason score ≥7. The median patient age was 64 years, PSA level 6.97 ng/mL and estimated prostate volume 52.2 mL. Of 1218 lesions, 48% (n = 581) were rated as Likert 1-2, 35% (n = 428) were Likert 3 and 17% (n = 209) were Likert 4-5. For Likert scores 1-5, the overall cancer detection rates were 12%, 13%, 22%, 50% and 59%, respectively, and the CSPC detection rates were 4%, 4%, 12%, 33% and 48%, respectively. Grading using the five-point scale showed strong positive correlation with overall cancer detection rate (r = 0.949, P = 0.05) and CSPC detection rate (r = 0.944, P = 0.05). By comparison, in Likert 4-5 lesions, significant differences were noted in overall cancer detection rate (63% vs 35%; P = 0.001) and CSPC detection rate (47% vs 29%; P = 0.027) for the more experienced vs the less experienced radiologists. The detection rates of overall cancer and CSPC strongly correlated with the five-point grading of the Likert scale. Among radiologists with different levels of experience, there were significant differences in these cancer detection rates. © 2017 The Authors BJU International © 2017 BJU International Published by John Wiley & Sons Ltd.

Perfluoroalkylated substances in edible livers of farm animals, including depuration behaviour in young sheep fed with contaminated grass.

PubMed

Zafeiraki, Effrosyni; Vassiliadou, Irene; Costopoulou, Danae; Leondiadis, Leondios; Schafft, Helmut A; Hoogenboom, Ron L A P; van Leeuwen, Stefan P J

2016-08-01

Perfluoroalkylated substances (PFASs) present a potential health risk for consumers. In animals these compounds are known to accumulate in livers. In order to determine potential PFASs contamination in commercially available livers, samples from farmed sheep, horses, cows, pigs and chicken were collected from the Dutch market. PFOS was the only detectable PFAS and its concentration was higher in free ranging animals like cows and sheep. The detected levels of PFOS in the liver samples were very low (up to 4.5 ng g(-1) ww). To further study the kinetic behaviour in foraging animals, samples from a study in which sheep were fed with grass obtained from a river floodplain, were examined. PFOS was the only detectable PFAS in the contaminated grass pellets, showing a level of about 0.5 μg kg(-1). Young blackhead sheep were fed with either clean or contaminated grass for a period up to 112 days. A time-dependent increase in liver PFOS concentrations was observed from 2.4 to 10.9 ng g(-1) ww after 8 and 112 days respectively. A time-dependent depuration was observed in livers of animals switched to clean grass after 56 days of exposure, from 9.2 to 4.7 ng g(-1) ww after 64 and 112 days respectively. The percentage of PFOS ingested from the grass and retained in the liver was estimated to be 12% at day 56, and decreased gradually to 6% after 56 days on clean grass, showing that the decrease in levels is not only caused by an increase in liver weight. Levels detected in commercial livers but also those in the sheep study would not lead to exceedance of the current TDI for PFOS set by EFSA. Therefore, it can be assumed that they do not present a risk for human health. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of mTOR/NF-κB signaling pathway and high thoracic epidural anesthesia on myocardial ischemia-reperfusion injury via autophagy in rats.

PubMed

Huang, Wei-Qiang; Wen, Jian-Lin; Lin, Ri-Qi; Wei, Peng; Huang, Feng

2018-09-01

We investigated the role of mammalian target of rapamycin/nuclear factor-kappa B (mTOR/NF-κB) signaling pathway in high thoracic epidural anesthesia (HTEA) against myocardial ischemia-reperfusion (I/R) injury in rats. The rat model of myocardial I/R injury was established. Ninety rats were divided into the normal, sham, I/R, eHTEA, the PDTC, and HTEA + PDTC groups. ELISA was applied to detect cardiac function indexes. HE staining was conducted to observe histopathological changes of myocardial tissues, and TTC staining was performed to detect the myocardial infarction size. TUNEL staining was adopted to detect the cell apoptosis rate. The mRNA and protein levels of mTOR, NF-κB, Fasl, Bcl-2 and Bax, and LC3-I, LC3-II, BNIP3, and Atg5 were detected by RT-qPCR and Western blotting, respectively. The findings indicated that compared with the normal and sham groups, the I/R, PDTC, and HTEA groups showed the larger myocardial infarction size and increased cell apoptosis rate, while the results in the HTEA + PDTC group were opposite. Compared with the normal and sham groups, the I/R group showed reduced mRNA and protein levels of Bcl-2, LC3, BNIP3, and Atg5, and elevated mRNA and protein levels of mTOR, p50, p65, Bax, and Fasl, while the HTEA + PDTC group revealed the opposite results, and the PDTC and HTEA group revealed the increased mRNA and protein levels of Bcl-2, LC3, BNIP3, Atg5, mTOR, p50, p65, Bax, and Fasl. These results prove that the inhibition of mTOR/NF-κB signaling pathway potentiates HTEA against myocardial IR injury by autophagy and apoptosis in rats. © 2017 Wiley Periodicals, Inc.

Mutacins and bacteriocins like genes in Streptococcus mutans isolated from participants with high, moderate, and low salivary count.

PubMed

Soto, Carolina; Padilla, Carlos; Lobos, Olga

2017-02-01

To detect S. mutans producers of mutacins and bacteriocins like substances (BLIS) from saliva of participants with low, moderate, and high salivary counts. 123 strains of S. mutans were obtained from participants with low, moderate, and high salivary counts (age 18 and 20 years old) and their antibacterial capacity analyzed. By using PCR amplification, the expression levels of mutacins and BLIS genes were studied (expressed in arbitrary units/ml) in all three levels. S. mutans strains from participants with low salivary counts show high production of mutacins (63%). In contrast, participants with moderate and high salivary counts depict relatively low levels of mutacins (22 and 15%, respectively). Moreover, participants with low salivary counts showed high expression levels of genes encoding mutacins, a result that correlates with the strong antimicrobial activity of the group. Participants with moderate and high salivary counts however depict low expression levels of mutacin related genes, and little antimicrobial activity. No BLIS were detected in any of the groups studied. S. mutans isolated from the saliva of participants with low bacterial counts have significant antibacterial capacity compared to that of participants with moderate and high salivary counts. The superior lethality of S. mutans in participants with low salivary counts is likely due to the augmented expression of mutacin- related genes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aging effects on the Binaural Interaction Component of the Auditory Brainstem Response in the Mongolian Gerbil: Effects of Interaural Time and Level Differences

PubMed Central

Laumen, Geneviève; Tollin, Daniel J.; Beutelmann, Rainer; Klump, Georg M.

2016-01-01

The effect of interaural time difference (ITD) and interaural level difference (ILD) on wave 4 of the binaural and summed monaural auditory brainstem responses (ABRs) as well as on the DN1 component of the binaural interaction component (BIC) of the ABR in young and old Mongolian gerbils (Meriones unguiculatus) was investigated. Measurements were made at a fixed sound pressure level (SPL) and a fixed level above visually detected ABR threshold to compensate for individual hearing threshold differences. In both stimulation modes (fixed SPL and fixed level above visually detected ABR threshold) an effect of ITD on the latency and the amplitude of wave 4 as well as of the BIC was observed. With increasing absolute ITD values BIC latencies were increased and amplitudes were decreased. ILD had a much smaller effect on these measures. Old animals showed a reduced amplitude of the DN1 component. This difference was due to a smaller wave 4 in the summed monaural ABRs of old animals compared to young animals whereas wave 4 in the binaural-evoked ABR showed no age-related difference. In old animals the small amplitude of the DN1 component was correlated with small binaural-evoked wave 1 and wave 3 amplitudes. This suggests that the reduced peripheral input affects central binaural processing which is reflected in the BIC. PMID:27173973

Qualitative and quantitative evaluation of a local lymph node assay based on ex vivo interleukin-2 production.

PubMed

Azam, Philippe; Peiffer, Jean-Luc; Ourlin, Jean-Claude; Bonnet, Pierre-Antoine; Tissier, Marie-Hélène; Vian, Laurence; Fabre, Isabelle

2005-01-15

The local lymph node assay (LLNA) is a regular method for the detection of sensitizing chemicals in mice which measures the incorporation of tritiated thymidine in lymph node cells. We have evaluated an alternative to this method based on the interleukin-2 (IL-2) production of lymph node cells. At the mRNA level, no change in the IL-2 gene expression level was detected by real-time PCR analysis. At the protein level, various experimental conditions were checked in order to improve the irritant versus sensitizer discrimination with a restricted set of prototypic compounds. In particular, the use of phytohemagglutinin A (PHA) in an ex vivo cell culture step showed an improvement of both signal and discrimination. In these optimised conditions, a panel of irritants and potency-graded sensitizers was used to assess the performance of the modified method. IFN-gamma production was used as a positive control. For each compound, a dose-response was performed and stimulation indexes (SI) were determined. Effective concentrations (EC) for each sensitizers were then extracted and compared to the literature data of the regular LLNA. The IL-2-based LLNA showed similar performances at both qualitative and quantitative levels compared to regular LLNA.

Fumonisin mycotoxins in human hair.

PubMed

Sewram, Vikash; Mshicileli, Ndumiso; Shephard, Gordon S; Marasas, Walter F O

2003-01-01

This study shows for the first time the accumulation of fumonisin mycotoxins in human hair of population clusters exposed to contaminated maize, and thus the feasibility of human hair analysis for the assessment of past fumonisin exposure. Composite hair samples were obtained from the Bizana, Butterworth and Centane districts within the Transkei region of the Eastern Cape Province of South Africa. Following methanol extraction and strong anion exchange clean up, the fumonisins FB(1), FB(2) and FB(3) were detected using high performance liquid chromatography coupled to electrospray ionization-mass spectrometry (HPLC-ESI-MS). Hair from Centane and Butterworth showed mean levels of FB(1) of 26.7 and 23.5 microg kg(-1) hair, respectively. FB(2) was only detected in hair from Centane and in one sampling point in Butterworth, with mean levels of 6.5 and 5.7 microg kg(-1) hair, respectively. Hair samples from Bizana, on the other hand, were found to contain higher levels of FB(1) (mean 33.0 microg kg(-1) hair) and FB(2) (mean 11.1 microg kg(-1) hair). No samples contained more than trace levels of FB(3). Recoveries from spiked hair samples using this method ranged from 81% to 101%, demonstrating the applicability of hair analysis in assessing human exposure to fumonisin mycotoxins.

Early Oscillation Detection Technique for Hybrid DC/DC Converters

NASA Technical Reports Server (NTRS)

Wang, Bright L.

2011-01-01

Oscillation or instability is a situation that must be avoided for reliable hybrid DC/DC converters. A real-time electronics measurement technique was developed to detect catastrophic oscillations at early stages for hybrid DC/DC converters. It is capable of identifying low-level oscillation and determining the degree of the oscillation at a unique frequency for every individual model of the converters without disturbing their normal operations. This technique is specially developed for space-used hybrid DC/DC converters, but it is also suitable for most of commercial and military switching-mode power supplies. This is a weak-electronic-signal detection technique to detect hybrid DC/DC converter oscillation presented as a specific noise signal at power input pins. It is based on principles of feedback control loop oscillation and RF signal modulations, and is realized by using signal power spectral analysis. On the power spectrum, a channel power amplitude at characteristic frequency (CPcf) and a channel power amplitude at switching frequency (CPsw) are chosen as oscillation level indicators. If the converter is stable, the CPcf is a very small pulse and the CPsw is a larger, clear, single pulse. At early stage of oscillation, the CPcf increases to a certain level and the CPsw shows a small pair of sideband pulses around it. If the converter oscillates, the CPcf reaches to a higher level and the CPsw shows more high-level sideband pulses. A comprehensive stability index (CSI) is adopted as a quantitative measure to accurately assign a degree of stability to a specific DC/DC converter. The CSI is a ratio of normal and abnormal power spectral density, and can be calculated using specified and measured CPcf and CPsw data. The novel and unique feature of this technique is the use of power channel amplitudes at characteristic frequency and switching frequency to evaluate stability and identify oscillations at an early stage without interfering with a DC/DC converter s normal operation. This technique eliminates the probing problem of a gain/phase margin method by connecting the power input to a spectral analyzer. Therefore, it is able to evaluate stability for all kinds of hybrid DC/DC converters with or without remote sense pins, and is suitable for real-time and in-circuit testing. This frequency-domain technique is more sensitive to detect oscillation at early stage than the time-domain method using an oscilloscope.

Minimal Internal Radiation Exposure in Residents Living South of the Fukushima Daiichi Nuclear Power Plant Disaster.

PubMed

Akiyama, Junichi; Kato, Shigeaki; Tsubokura, Masaharu; Mori, Jinichi; Tanimoto, Tetsuya; Abe, Koichiro; Sakai, Shuji; Hayano, Ryugo; Tokiwa, Michio; Shimmura, Hiroaki

2015-01-01

Following the Fukushima nuclear power plant disaster, assessment of internal radiation exposure was indispensable to predict radiation-related health threats to residents of neighboring areas. Although many evaluations of internal radiation in residents living north and west of the crippled Fukushima nuclear power plant are available, there is little information on residents living in areas south of the plant, which were similarly affected by radio-contamination from the disaster. To assess the internal radio-contamination in residents living in affected areas to the south of the plant or who were evacuated into Iwaki city, a whole body counter (WBC) screening program of internal radio-contamination was performed on visitors to the Jyoban hospital in Iwaki city, which experienced less contamination than southern areas adjacent to the nuclear plant. The study included 9,206 volunteer subjects, of whom 6,446 were schoolchildren aged 4-15 years. Measurements began one year after the incident and were carried out over the course of two years. Early in the screening period only two schoolchildren showed Cs-137 levels that were over the detection limit (250 Bq/body), although their Cs-134 levels were below the detection limit (220 Bq/body). Among the 2,760 adults tested, 35 (1.3%) had detectable internal radio-contamination, but only for Cs-137 (range: 250 Bq/body to 859 Bq/body), and not Cs-134. Of these 35 subjects, nearly all (34/35) showed elevated Cs-137 levels only during the first year of the screening. With the exception of potassium 40, no other radionuclides were detected during the screening period. The maximum annual effective dose calculated from the detected Cs-137 levels was 0.029 and 0.028 mSv/year for the schoolchildren and adults, respectively, which is far below the 1 mSv/year limit set by the government of Japan. Although the data for radiation exposure during the most critical first year after the incident are unavailable due to a lack of systemic measurements, the present results suggest that internal radio-contamination levels more than one year after the incident were minimal for residents living south of the crippled Fukushima nuclear plant, and that the annual additional effective doses derived from internal Cs contamination were negligible. Thus, internal radio-contamination of residents living in southern radio-contaminated areas appears to be generally well controlled.

Determination of steroid sex hormones in water and urine matrices by stir bar sorptive extraction and liquid chromatography with diode array detection.

PubMed

Almeida, C; Nogueira, J M F

2006-06-16

In this study, stir bar sorptive extraction and liquid desorption followed by high performance liquid chromatography with diode array detection (SBSE-LD-HPLC/DAD) were combined for the simultaneous determination of nine steroid sex hormones (estrone, 17alpha-estradiol, 17beta-estradiol, 17alpha-ethynylestradiol, diethylstilbestrol, mestranol, progesterone, 19-norethisterone and norgestrel) in water and urine matrices. During the method development, it has been demonstrated that equilibrium time, ionic strength and back extraction solvents are the most important parameters to control, for determining the nine-hormones in water matrices, in which stir bars coated with 126 microl of polydimethylsiloxane were used. Assays performed on 30 ml water samples spiked at 10 microg/l levels under optimised experimental conditions, yielded recoveries ranging from 11.1+/-4.9% (17beta-estradiol) to 100.2+/-10.4% (mestranol), showed that the methodology is well described by the octanol-water partition coefficients (K(PDMS/W) approximately K(O/W)) for the latter, while pronounced deviations to the theoretical efficiency (K(PDMS/W) not equal K(O/W)) were observed for the remaining hormones. From calibration studies, a good analytical performance for all hormones was attained, including a suitable precision (2.1-17.1%), low limits of detection (0.3-1.0 microg/l) and an excellent linear dynamic range (1.25-50.0 microg/l). Assays on environmental water and urine matrices showed recovery yields in worthy good agreement with the spiking level (10 microg/l), and suitability for profiling low microg/l levels of natural hormones in urine samples taken from pregnant women. The present methodology is easy, reliable and sensitive at the trace level, only requiring a low sample volume, showing to be a good analytical alternative to routine quality control for environmental and biomedical laboratories.

Changes in serum sex steroid levels throughout the reproductive cycle of Bufo arenarum females.

PubMed

Medina, Marcela F; Ramos, Inés; Crespo, Claudia A; González-Calvar, Silvia; Fernández, Silvia N

2004-04-01

The changes in the serum levels of the sexual steroids estradiol-17beta (E(2)), testosterone (T), dihydrotestosterone (DHT), and progesterone (P) in Bufo arenarum females were determined by radioimmunoassay (RIA) during 3 consecutive cycles (1999-2001). The serum concentrations of T and DHT, which showed a close parallelism during the annual reproductive cycle, exhibited the highest levels during the preovulatory period, when oogenesis is advanced, while lowest serum levels of these hormones were found during the ovulatory period. The data obtained for E(2) showed a pattern contrary to that determined for androgens. The maximum E(2) concentrations detected in the early postovulatory period might be associated with vitellogenesis and follicular growth. Lowest E(2) concentrations were reached during the period in which B. arenarum undergoes its final hibernation stage. Serum P showed a peak during the preovulatoy period, related to the induction of nuclear maturation in full grown oocytes. A strong decrease in the levels of the circulating hormones was observed after ovariectomy. Our results showed that, out of the four hormones examined, T and DHT were the best indicators of ovarian and oviductal stage, as shown by the strong positive correlation found between androgen levels and organ weight, while E(2) showed a weak negative correlation with ovarian and oviductal weight.

Towards a global flood detection system using social media

NASA Astrophysics Data System (ADS)

de Bruijn, Jens; de Moel, Hans; Jongman, Brenden; Aerts, Jeroen

2017-04-01

It is widely recognized that an early warning is critical in improving international disaster response. Analysis of social media in real-time can provide valuable information about an event or help to detect unexpected events. For successful and reliable detection systems that work globally, it is important that sufficient data is available and that the algorithm works both in data-rich and data-poor environments. In this study, both a new geotagging system and multi-level event detection system for flood hazards was developed using Twitter data. Geotagging algorithms that regard one tweet as a single document are well-studied. However, no algorithms exist that combine several sequential tweets mentioning keywords regarding a specific event type. Within the time frame of an event, multiple users use event related keywords that refer to the same place name. This notion allows us to treat several sequential tweets posted in the last 24 hours as one document. For all these tweets, we collect a series of spatial indicators given in the tweet metadata and extract additional topological indicators from the text. Using these indicators, we can reduce ambiguity and thus better estimate what locations are tweeted about. Using these localized tweets, Bayesian change-point analysis is used to find significant increases of tweets mentioning countries, provinces or towns. In data-poor environments detection of events on a country level is possible, while in other, data-rich, environments detection on a city level is achieved. Additionally, on a city-level we analyse the spatial dependence of mentioned places. If multiple places within a limited spatial extent are mentioned, detection confidence increases. We run the algorithm using 2 years of Twitter data with flood related keywords in 13 major languages and validate against a flood event database. We find that the geotagging algorithm yields significantly more data than previously developed algorithms and successfully deals with ambiguous place names. In addition, we show that our detection system can both quickly and reliably detect floods, even in countries where data is scarce, while achieving high detail in countries where more data is available.

Low-contrast detectability in volume rendering: a phantom study on multidetector-row spiral CT data.

PubMed

Shin, Hoen-Oh; Falck, Christian V; Galanski, Michael

2004-02-01

To cope with the increasing amount of CT data, there is growing interest in direct volume-rendering techniques (VRT) as a diagnostic tool. The aim of this phantom study was to analyze the low-contrast detectability (LCD) of VRT compared with multi-planar reformations (MPR). Soft tissue lesions were simulated by spheres of different diameters (3-8 mm). The average lesion density was 15 HU compared with a background density of 35 HU. Two different CT protocols with 40 and 150 mAs were performed on a multi-detector row CT. The scanning parameters were as following: 140 kV; 2x0.5-mm slice collimation; pitch 2 (table movement per rotation/single slice collimation), and reconstruction with 0.5-mm slice thickness at 0.5-mm interval. A B30 kernel was used for reconstruction. The VRT was performed by mapping Hounsfield values to gray levels equal to a CT window (center: 60 HU; window: 370 HU ). A linear ramp was applied for the opacity transfer function varying the maximum opacity between 0.1 and 1.0. A statistical method based on the Rose model was used to calculate the detection threshold depending on lesion size and image noise. Additionally, clinical data of 2 patients with three liver lesions of different sizes and density were evaluated. In VRT, LCD was most dependent on object size. Regarding lesions larger than 5 mm, VRT is significantly superior to MPR (p<0.05) for all opacity settings. In lesions sized 3-5 mm a maximum opacity level approximately 40-50% showed a near equivalent detectability in VRT and MPR. For higher opacity levels VRT was superior to MPR. Only for 3-mm lesions MPR performed slightly better in low-contrast detectability (p<0.05). Compared with MPR, VRT shows similar performance in LCD. Due to noise suppression effects, it is suited for visualization of data with high noise content.

Improved detection probability of low level light and infrared image fusion system

NASA Astrophysics Data System (ADS)

Luo, Yuxiang; Fu, Rongguo; Zhang, Junju; Wang, Wencong; Chang, Benkang

2018-02-01

Low level light(LLL) image contains rich information on environment details, but is easily affected by the weather. In the case of smoke, rain, cloud or fog, much target information will lose. Infrared image, which is from the radiation produced by the object itself, can be "active" to obtain the target information in the scene. However, the image contrast and resolution is bad, the ability of the acquisition of target details is very poor, and the imaging mode does not conform to the human visual habit. The fusion of LLL and infrared image can make up for the deficiency of each sensor and give play to the advantages of single sensor. At first, we show the hardware design of fusion circuit. Then, through the recognition probability calculation of the target(one person) and the background image(trees), we find that the trees detection probability of LLL image is higher than that of the infrared image, and the person detection probability of the infrared image is obviously higher than that of LLL image. The detection probability of fusion image for one person and trees is higher than that of single detector. Therefore, image fusion can significantly enlarge recognition probability and improve detection efficiency.

Gold-coated carbon nanotube electrode arrays: Immunosensors for impedimetric detection of bone biomarkers.

PubMed

Ramanathan, Madhumati; Patil, Mitali; Epur, Rigved; Yun, Yeoheung; Shanov, Vasselin; Schulz, Mark; Heineman, William R; Datta, Moni K; Kumta, Prashant N

2016-03-15

C-terminal telopeptide (cTx), a fragment generated during collagen degradation, is a key biomarker of bone resorption during the bone remodeling process. The presence of varying levels of cTx in the bloodstream can hence be indicative of abnormal bone metabolism. This study focuses on the development of an immunosensor utilizing carbon nanotube (CNT) electrodes coated with gold nanoparticles for the detection of cTx, which could ultimately lead to the development of an inexpensive and rapid point-of-care (POC) tool for bone metabolism detection and prognostics. Electrochemical impedance spectroscopy (EIS) was implemented to monitor and detect the antigen-antibody binding events occurring on the surface of the gold-deposited CNT electrode. Type I cTx was used as the model protein to test the developed sensor. The sensor was accordingly characterized at various stages of development for evaluation of the optimal sensor performance. The biosensor could detect cTx levels as low as 0.05 ng/mL. The feasibility of the sensor for point-of-care (POC) applications was further demonstrated by determining the single frequency showing maximum changes in impedance, which was determined to be 18.75 Hz. Copyright © 2015 Elsevier B.V. All rights reserved.

Online Detection of Driver Fatigue Using Steering Wheel Angles for Real Driving Conditions.

PubMed

Li, Zuojin; Li, Shengbo Eben; Li, Renjie; Cheng, Bo; Shi, Jinliang

2017-03-02

This paper presents a drowsiness on-line detection system for monitoring driver fatigue level under real driving conditions, based on the data of steering wheel angles (SWA) collected from sensors mounted on the steering lever. The proposed system firstly extracts approximate entropy (ApEn)featuresfromfixedslidingwindowsonreal-timesteeringwheelanglestimeseries. Afterthat, this system linearizes the ApEn features series through an adaptive piecewise linear fitting using a given deviation. Then, the detection system calculates the warping distance between the linear features series of the sample data. Finally, this system uses the warping distance to determine the drowsiness state of the driver according to a designed binary decision classifier. The experimental data were collected from 14.68 h driving under real road conditions, including two fatigue levels: "wake" and "drowsy". The results show that the proposed system is capable of working online with an average 78.01% accuracy, 29.35% false detections of the "awake" state, and 15.15% false detections of the "drowsy" state. The results also confirm that the proposed method based on SWA signal is valuable for applications in preventing traffic accidents caused by driver fatigue.

Online Detection of Driver Fatigue Using Steering Wheel Angles for Real Driving Conditions

PubMed Central

Li, Zuojin; Li, Shengbo Eben; Li, Renjie; Cheng, Bo; Shi, Jinliang

2017-01-01

This paper presents a drowsiness on-line detection system for monitoring driver fatigue level under real driving conditions, based on the data of steering wheel angles (SWA) collected from sensors mounted on the steering lever. The proposed system firstly extracts approximate entropy (ApEn) features from fixed sliding windows on real-time steering wheel angles time series. After that, this system linearizes the ApEn features series through an adaptive piecewise linear fitting using a given deviation. Then, the detection system calculates the warping distance between the linear features series of the sample data. Finally, this system uses the warping distance to determine the drowsiness state of the driver according to a designed binary decision classifier. The experimental data were collected from 14.68 h driving under real road conditions, including two fatigue levels: “wake” and “drowsy”. The results show that the proposed system is capable of working online with an average 78.01% accuracy, 29.35% false detections of the “awake” state, and 15.15% false detections of the “drowsy” state. The results also confirm that the proposed method based on SWA signal is valuable for applications in preventing traffic accidents caused by driver fatigue. PMID:28257094

Spiny Nanorod and Upconversion Nanoparticle Satellite Assemblies for Ultrasensitive Detection of Messenger RNA in Living Cells.

PubMed

Gao, Rui; Hao, Changlong; Xu, Liguang; Xu, Chuanlai; Kuang, Hua

2018-04-17

Quantitation and in situ monitoring of target mRNA (mRNA) in living cells remains a significant challenge for the chemical and biomedical communities. To quantitatively detect mRNA expression levels in living cells, we have developed DNA-driven gold nanorod coated platinum-upconversion nanoparticle satellite assemblies (termed Au NR@Pt-UCNP satellites) for intracellular thymidine kinase 1 (TK1) mRNA analysis. The nanostructures were capable of recognizing target mRNA in a sequence-specific manner as luminescence of UCNPs was effectively quenched by Au NR@Pt within the assemblies. Following recognition, UCNPs detached from Au NR@Pt, resulting in luminescence restoration to achieve effective in situ imaging and quantifiable detection of target mRNA. The upconversional luminescence intensity of confocal images showed a good linear relationship with intracellular TK1 mRNA ranging from 1.17 to 65.21 fmol/10 μg RNA and a limit of detection (LOD) of 0.67 fmol/10 μg RNA. We believe that our present assay can be broadly applied for detection of endogenous biomolecules at the cellular and tissue levels and restoration of tissue homeostasis in vivo.

Detection of high-frequency energy level changes in speech and singing

PubMed Central

Monson, Brian B.; Lotto, Andrew J.; Story, Brad H.

2014-01-01

Previous work has shown that human listeners are sensitive to level differences in high-frequency energy (HFE) in isolated vowel sounds produced by male singers. Results indicated that sensitivity to HFE level changes increased with overall HFE level, suggesting that listeners would be more “tuned” to HFE in vocal production exhibiting higher levels of HFE. It follows that sensitivity to HFE level changes should be higher (1) for female vocal production than for male vocal production and (2) for singing than for speech. To test this hypothesis, difference limens for HFE level changes in male and female speech and singing were obtained. Listeners showed significantly greater ability to detect level changes in singing vs speech but not in female vs male speech. Mean differences limen scores for speech and singing were about 5 dB in the 8-kHz octave (5.6–11.3 kHz) but 8–10 dB in the 16-kHz octave (11.3–22 kHz). These scores are lower (better) than those previously reported for isolated vowels and some musical instruments. PMID:24437780

A novel bicistronic sensor vector for detecting caspase-3 activation.

PubMed

Vagner, Tatyana; Mouravlev, Alexandre; Young, Deborah

2015-01-01

Apoptosis is involved in pathological cell death of a wide range of human diseases. One of the most important biochemical markers of apoptosis is activation of caspase-3. Ability to detect caspase-3 activation early in the pathological process is important for determining the timing for interfering with apoptosis initiation and prevention of cell damage. Techniques allowing detection of caspase-3 activity at a single cell level show increased sensitivity, compared to biochemical assays; therefore, we developed a novel bicistronic caspase-3 sensor vector enabling detection of caspase-3 activity in individual cells. We employed green fluorescent protein (GFP) as a reporter for caspase-3 activation in our constructs and assessed the functionality of the generated constructs in transiently transfected Neuro2A and HEK293 cells under basal conditions and following application of okadaic acid (OA) or staurosporine (STS) to induce apoptosis. To ensure responsiveness of the new sensor vector to active caspase-3, we co-transfected the sensor with plasmid(s) overexpressing active caspase-3 and quantified GFP fluorescence using a plate reader. We observed an increase in GFP expression in cells transfected with the new bicistronic caspase-3 sensor in response to both OA and STS. We also showed a significant increase in GFP fluorescence intensity in cells co-expressing the sensor with the plasmid(s) encoding active caspase-3. We generated a novel bicistronic caspase-3 sensor vector which relies on a transcription factor/response element system. The obtained sensor combines high sensitivity of the single cell level detection with the possibility of automated quantification. Copyright © 2015 Elsevier Inc. All rights reserved.

Highly selective aptamer based organic electrochemical biosensor with pico-level detection.

PubMed

Saraf, Nileshi; Woods, Eric R; Peppler, Madison; Seal, Sudipta

2018-05-22

An organic aptamer functionalized electrochemical transistor has been developed to detect the presence of epinephrine molecule which acts as an excitatory neurotransmitter. The abnormalities in the level of epinephrine are the direct symptoms of some diseases such as Takotsubo cardiomyopathy, myocardial infarction, arrhythmias and other heart related diseases. The present approach is based on immobilization of aptamers on the gate electrode which selectively binds to epinephrine with high affinity. The introduction of epinephrine in the system causes screening of negative charge of aptamers as well as the production of Faradaic current due to oxidation of epinephrine. The synergistic effect of these two events decreases the overall channel current which was seen in both transfer characteristics and current-time curve. Additional experiments against common interfering agents (dopamine, ascorbic acid, DOPAC etc) showed no decrease in the current which indicates high specificity of the sensor. Overall, the incorporation of aptamers in the transistor has allowed us to obtain a sensor exhibiting the lowest limit of detection for epinephrine (90 pM) till date which is comparable to normal physiological level. This approach provides a real-time detection of a large range of biomolecules and viral proteins in a time and cost-effective manner and has applications in point-of-care testing tool for several diagnostic applications. Published by Elsevier B.V.

The Effect of Consistency on Short-Term Memory for Scenes.

PubMed

Gong, Mingliang; Xuan, Yuming; Xu, Xinwen; Fu, Xiaolan

2017-01-01

Which is more detectable, the change of a consistent or an inconsistent object in a scene? This question has been debated for decades. We noted that the change of objects in scenes might simultaneously be accompanied with gist changes. In the present study we aimed to examine how the alteration of gist, as well as the consistency of the changed objects, modulated change detection. In Experiment 1, we manipulated the semantic content by either keeping or changing the consistency of the scene. Results showed that the changes of consistent and inconsistent scenes were equally detected. More importantly, the changes were more accurately detected when scene consistency changed than when the consistency remained unchanged, regardless of the consistency of the memory scenes. A phase-scrambled version of stimuli was adopted in Experiment 2 to decouple the possible confounding effect of low-level factors. The results of Experiment 2 demonstrated that the effect found in Experiment 1 was indeed due to the change of high-level semantic consistency rather than the change of low-level physical features. Together, the study suggests that the change of consistency plays an important role in scene short-term memory, which might be attributed to the sensitivity to the change of semantic content.

The Effect of Consistency on Short-Term Memory for Scenes

PubMed Central

Gong, Mingliang; Xuan, Yuming; Xu, Xinwen; Fu, Xiaolan

2017-01-01

Which is more detectable, the change of a consistent or an inconsistent object in a scene? This question has been debated for decades. We noted that the change of objects in scenes might simultaneously be accompanied with gist changes. In the present study we aimed to examine how the alteration of gist, as well as the consistency of the changed objects, modulated change detection. In Experiment 1, we manipulated the semantic content by either keeping or changing the consistency of the scene. Results showed that the changes of consistent and inconsistent scenes were equally detected. More importantly, the changes were more accurately detected when scene consistency changed than when the consistency remained unchanged, regardless of the consistency of the memory scenes. A phase-scrambled version of stimuli was adopted in Experiment 2 to decouple the possible confounding effect of low-level factors. The results of Experiment 2 demonstrated that the effect found in Experiment 1 was indeed due to the change of high-level semantic consistency rather than the change of low-level physical features. Together, the study suggests that the change of consistency plays an important role in scene short-term memory, which might be attributed to the sensitivity to the change of semantic content. PMID:29046654

Micromachined optical microphone structures with low thermal-mechanical noise levels.

PubMed

Hall, Neal A; Okandan, Murat; Littrell, Robert; Bicen, Baris; Degertekin, F Levent

2007-10-01

Micromachined microphones with diffraction-based optical displacement detection have been introduced previously [Hall et al., J. Acoust. Soc. Am. 118, 3000-3009 (2005)]. The approach has the advantage of providing high displacement detection resolution of the microphone diaphragm independent of device size and capacitance-creating an unconstrained design space for the mechanical structure itself. Micromachined microphone structures with 1.5-mm-diam polysilicon diaphragms and monolithically integrated diffraction grating electrodes are presented in this work with backplate architectures that deviate substantially from traditional perforated plate designs. These structures have been designed for broadband frequency response and low thermal mechanical noise levels. Rigorous experimental characterization indicates a diaphragm displacement detection resolution of 20 fm radicalHz and a thermal mechanical induced diaphragm displacement noise density of 60 fm radicalHz, corresponding to an A-weighted sound pressure level detection limit of 24 dB(A) for these structures. Measured thermal mechanical displacement noise spectra are in excellent agreement with simulations based on system parameters derived from dynamic frequency response characterization measurements, which show a diaphragm resonance limited bandwidth of approximately 20 kHz. These designs are substantial improvements over initial prototypes presented previously. The high performance-to-size ratio achievable with this technology is expected to have an impact on a variety of instrumentation and hearing applications.

Implication of circulating irisin levels with brown adipose tissue and sarcopenia in humans.

PubMed

Choi, Hae Yoon; Kim, Sungeun; Park, Ji Woo; Lee, Nam Seok; Hwang, Soon Young; Huh, Joo Young; Hong, Ho Cheol; Yoo, Hye Jin; Baik, Sei Hyun; Youn, Byung-Soo; Mantzoros, Christos S; Choi, Kyung Mook

2014-08-01

Irisin is an exercise-induced novel myokine that drives brown-fat-like conversion of white adipose tissue and has been suggested to be a promising target for the treatment of obesity-related metabolic disorders. To assess the association of circulating irisin concentrations with brown adipose tissue (BAT) and/or sarcopenia in humans. We examined irisin levels in 40 BAT-positive and 40 BAT-negative women detected by (18)F-fluorodeoxyglucose positron emission tomography ((18)FDG-PET). In a separate study, we also examined 401 subjects with or without sarcopenia defined by skeletal muscle mass index (SMMI) and appendicular skeletal muscle (ASM)/height(2) using dual-energy x-ray absorptiometry. Among 6877 consecutive (18)FDG-PET scans in 4736 subjects, 146 subjects (3.1%) had positive BAT scans. The BAT-detectable group and the matched BAT-undetectable group did not differ in circulating irisin levels measured using two different ELISA kits (P = .747 and P = .160, respectively). Serum irisin levels were not different between individuals with sarcopenia and those without sarcopenia using either kit (P = .305 and P = .569, respectively). Also, serum irisin levels were not different between groups defined by ASM/height(2) using either kit (P = .352 and P = .134, respectively). Although visceral fat area and skeletal muscle mass showed significant difference according to tertiles of SMMI levels, irisin concentrations did not differ. Circulating irisin levels were not different in individuals with detectable BAT or those with sarcopenia compared with control subjects and were not correlated with SMMI.

Rapid detection of cancer related DNA nanoparticulate biomarkers and nanoparticles in whole blood

NASA Astrophysics Data System (ADS)

Heller, Michael J.; Krishnan, Raj; Sonnenberg, Avery

2010-08-01

The ability to rapidly detect cell free circulating (cfc) DNA, cfc-RNA, exosomes and other nanoparticulate disease biomarkers as well as drug delivery nanoparticles directly in blood is a major challenge for nanomedicine. We now show that microarray and new high voltage dielectrophoretic (DEP) devices can be used to rapidly isolate and detect cfc-DNA nanoparticulates and nanoparticles directly from whole blood and other high conductance samples (plasma, serum, urine, etc.). At DEP frequencies of 5kHz-10kHz both fluorescent-stained high molecular weight (hmw) DNA, cfc-DNA and fluorescent nanoparticles separate from the blood and become highly concentrated at specific DEP highfield regions over the microelectrodes, while blood cells move to the DEP low field-regions. The blood cells can then be removed by a simple fluidic wash while the DNA and nanoparticles remain highly concentrated. The hmw-DNA could be detected at a level of <260ng/ml and the nanoparticles at <9.5 x 109 particles/ml, detection levels that are well within the range for viable clinical diagnostics and drug nanoparticle monitoring. Disease specific cfc-DNA materials could also be detected directly in blood from patients with Chronic Lymphocytic Leukemia (CLL) and confirmed by PCR genotyping analysis.

Rapid and label-free bioanalytical method of alpha fetoprotein detection using LSPR chip

NASA Astrophysics Data System (ADS)

Kim, Dongjoo; Kim, Jinwoon; Kwak, Cheol Hwan; Heo, Nam Su; Oh, Seo Yeong; Lee, Hoomin; Lee, Go-Woon; Vilian, A. T. Ezhil; Han, Young-Kyu; Kim, Woo-Sik; Kim, Gi-bum; Kwon, Soonjo; Huh, Yun Suk

2017-07-01

Alpha fetoprotein (AFP) is a cancer marker, particularly for hepatocellular carcinoma. Normal levels of AFP are less than 20 ng/mL; however, its levels can reach more than 400 ng/mL in patients with HCC. Enzyme linked immunosorbent assay (ELISA) and radioimmunoassay (RIA) have been employed for clinical diagnosis of AFP; however, these methods are time consuming and labor intensive. In this study, we developed a localized surface plasmon resonance (LSPR) based biosensor for simple and rapid detection of AFP. This biosensor consists of a UV-Vis spectrometer, a cuvette cell, and a biosensor chip nanopatterned with gold nanoparticles (AuNPs). In our LSPR biosensor, binding of AFP to the surface of the sensor chip led to an increasing magnitude of the LSPR signals, which was measured by an ultraviolet-visible (UV-Vis) spectrometer. Our LSPR biosensor showed sufficient detectability of AFP at concentrations of 1 ng/mL to 1 μg/mL. Moreover, the overall procedure for detection of AFP was completed within 20 min. This biosensor could also be utilized for a point of care test (POCT) by employing a portable UV-Vis spectrometer. Owing to the simplicity and rapidity of the detection process, our LSPR biosensor is expected to replace traditional diagnostic methods for the early detection of diseases.

X-RAY ABSORPTION BY THE WARM-HOT INTERGALACTIC MEDIUM IN THE HERCULES SUPERCLUSTER

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

Ren, Bin; Fang, Taotao; Buote, David A., E-mail: fangt@xmu.edu.cn

2014-02-10

''Missing baryons'', in the form of warm-hot intergalactic medium (WHIM), are expected to reside in cosmic filamentary structures that can be traced by signposts such as large-scale galaxy superstructures. The clear detection of an X-ray absorption line in the Sculptor Wall demonstrated the success of using galaxy superstructures as a signpost to search for the WHIM. Here we present an XMM -Newton Reflection Grating Spectrometer observation of the blazar Mkn 501, located in the Hercules Supercluster. We detected an O VII Kα absorption line at the 98.7% level (2.5σ) at the redshift of the foreground Hercules Supercluster. The derived properties of themore » absorber are consistent with theoretical expectations of the WHIM. We discuss the implication of our detection for the search for the ''missing baryons''. While this detection shows again that using signposts is a very effective strategy to search for the WHIM, follow-up observations are crucial both to strengthen the statistical significance of the detection and to rule out other interpretations. A local, z ∼ 0 O VII Kα absorption line was also clearly detected at the 4σ level, and we discuss its implications for our understanding of the hot gas content of our Galaxy.« less

Novel colorimetric sensor for oral malodour.

PubMed

Alagirisamy, Nethaji; Hardas, Sarita S; Jayaraman, Sujatha

2010-02-19

Volatile sulphur compounds are the primary constituents of oral malodour. Quantitative tools for the detection of oral malodour are beneficial to evaluate the intensity of malodour, analyse its causes and monitor the effectiveness of customized treatments. We have developed an objective, cost effective, do-it-yourself colorimetric sensor for oral malodour quantification. The sensor consisted of a sensing solution, a gas sampling unit for collecting a known volume of mouth air and a photometric detector. The sensing solution was iodine and the depletion of iodine on reaction with hydrogen sulphide was detected colorimetrically using starch. The detection limit of the sensor is 0.05 microg L(-1) of hydrogen sulphide, which is fit-for-purpose for oral malodour detection in healthy subjects as well as halitosis patients. Volatile sulphur compounds in mouth air were quantified in healthy human volunteers using this portable sensor and the detected levels were in the range of 0.2-0.4 microg L(-1). There was a good correlation between the VSC levels detected by the colorimetric sensor and halimeter (R(2)=0.934). The developed sensor can be easily fabricated in the laboratory, and it shows high potential to be used as a clinical evaluation tool for oral malodour assessments. Copyright 2009 Elsevier B.V. All rights reserved.

Use of a Chagas Urine Nanoparticle Test (Chunap) to Correlate with Parasitemia Levels in T. cruzi/HIV Co-infected Patients.

PubMed

Castro-Sesquen, Yagahira E; Gilman, Robert H; Mejia, Carolina; Clark, Daniel E; Choi, Jeong; Reimer-McAtee, Melissa J; Castro, Rosario; Valencia-Ayala, Edward; Flores, Jorge; Bowman, Natalie; Castillo-Neyra, Ricardo; Torrico, Faustino; Liotta, Lance; Bern, Caryn; Luchini, Alessandra

2016-02-01

Early diagnosis of reactivated Chagas disease in HIV patients could be lifesaving. In Latin America, the diagnosis is made by microscopical detection of the T. cruzi parasite in the blood; a diagnostic test that lacks sensitivity. This study evaluates if levels of T. cruzi antigens in urine, determined by Chunap (Chagas urine nanoparticle test), are correlated with parasitemia levels in T. cruzi/HIV co-infected patients. T. cruzi antigens in urine of HIV patients (N = 55: 31 T. cruzi infected and 24 T. cruzi serology negative) were concentrated using hydrogel particles and quantified by Western Blot and a calibration curve. Reactivation of Chagas disease was defined by the observation of parasites in blood by microscopy. Parasitemia levels in patients with serology positive for Chagas disease were classified as follows: High parasitemia or reactivation of Chagas disease (detectable parasitemia by microscopy), moderate parasitemia (undetectable by microscopy but detectable by qPCR), and negative parasitemia (undetectable by microscopy and qPCR). The percentage of positive results detected by Chunap was: 100% (7/7) in cases of reactivation, 91.7% (11/12) in cases of moderate parasitemia, and 41.7% (5/12) in cases of negative parasitemia. Chunap specificity was found to be 91.7%. Linear regression analysis demonstrated a direct relationship between parasitemia levels and urine T. cruzi antigen concentrations (p<0.001). A cut-off of > 105 pg was chosen to determine patients with reactivation of Chagas disease (7/7). Antigenuria levels were 36.08 times (95% CI: 7.28 to 64.88) higher in patients with CD4+ lymphocyte counts below 200/mL (p = 0.016). No significant differences were found in HIV loads and CD8+ lymphocyte counts. Chunap shows potential for early detection of Chagas reactivation. With appropriate adaptation, this diagnostic test can be used to monitor Chagas disease status in T. cruzi/HIV co-infected patients.

Use of a Chagas Urine Nanoparticle Test (Chunap) to Correlate with Parasitemia Levels in T. cruzi/HIV Co-infected Patients

PubMed Central

Castro-Sesquen, Yagahira E.; Gilman, Robert H.; Mejia, Carolina; Clark, Daniel E.; Choi, Jeong; Reimer-McAtee, Melissa J.; Castro, Rosario; Valencia-Ayala, Edward; Flores, Jorge; Bowman, Natalie; Castillo-Neyra, Ricardo; Torrico, Faustino; Liotta, Lance; Bern, Caryn; Luchini, Alessandra

2016-01-01

Background Early diagnosis of reactivated Chagas disease in HIV patients could be lifesaving. In Latin America, the diagnosis is made by microscopical detection of the T. cruzi parasite in the blood; a diagnostic test that lacks sensitivity. This study evaluates if levels of T. cruzi antigens in urine, determined by Chunap (Chagas urine nanoparticle test), are correlated with parasitemia levels in T. cruzi/HIV co-infected patients. Methodology/Principal Findings T. cruzi antigens in urine of HIV patients (N = 55: 31 T. cruzi infected and 24 T. cruzi serology negative) were concentrated using hydrogel particles and quantified by Western Blot and a calibration curve. Reactivation of Chagas disease was defined by the observation of parasites in blood by microscopy. Parasitemia levels in patients with serology positive for Chagas disease were classified as follows: High parasitemia or reactivation of Chagas disease (detectable parasitemia by microscopy), moderate parasitemia (undetectable by microscopy but detectable by qPCR), and negative parasitemia (undetectable by microscopy and qPCR). The percentage of positive results detected by Chunap was: 100% (7/7) in cases of reactivation, 91.7% (11/12) in cases of moderate parasitemia, and 41.7% (5/12) in cases of negative parasitemia. Chunap specificity was found to be 91.7%. Linear regression analysis demonstrated a direct relationship between parasitemia levels and urine T. cruzi antigen concentrations (p<0.001). A cut-off of > 105 pg was chosen to determine patients with reactivation of Chagas disease (7/7). Antigenuria levels were 36.08 times (95% CI: 7.28 to 64.88) higher in patients with CD4+ lymphocyte counts below 200/mL (p = 0.016). No significant differences were found in HIV loads and CD8+ lymphocyte counts. Conclusion Chunap shows potential for early detection of Chagas reactivation. With appropriate adaptation, this diagnostic test can be used to monitor Chagas disease status in T. cruzi/HIV co-infected patients. PMID:26919324

Blastocystis sp. in Irritable Bowel Syndrome (IBS)--Detection in Stool Aspirates during Colonoscopy.

PubMed

Ragavan, Nanthiney Devi; Kumar, Suresh; Chye, Tan Tian; Mahadeva, Sanjiv; Shiaw-Hooi, Ho

2015-01-01

Blastocystis is one of the most common gut parasites found in the intestinal tract of humans and animals. Its' association with IBS is controversial, possibly as a result of irregular shedding of parasites in stool and variation in stool detection. We aimed to screen for Blastocystis in colonic stool aspirate samples in adult patients with and without IBS undergoing colonoscopy for various indications and measure the interleukin levels (IL-8, IL-3 and IL-5). In addition to standard stool culture techniques, polymerase chain reaction (PCR) techniques were employed to detect and subtype Blastocystis. All the serum samples collected were subjected for ELISA studies to measure the interleukin levels (IL-8, IL-3 and IL-5). Among 109 (IBS n = 35 and non-IBS n = 74) adults, direct stool examination and culture of colonic aspirates were initially negative for Blastocystis. However, PCR analysis detected Blastocystis in 6 (17%) IBS and 4 (5.5%) non-IBS patients. In the six positive IBS patients by PCR method, subtype 3 was shown to be the most predominant (3/6: 50%) followed by subtype 4 (2/6; 33.3%) and subtype 5 (1/6; 16.6%). IL-8 levels were significantly elevated in the IBS Blasto group and IBS group (p<0.05) compared to non-IBS and non-IBS Blasto group. The level of IL-3 in were seen to be significantly higher in than IBS Blasto group and IBS group (p<0.05) compared to non-IBS. Meanwhile, the IL-5 levels were significantly higher in IBS Blasto group (p<0.05) compared to non-IBS and non-IBS Blasto group. This study implicates that detecting Blastosystis by PCR method using colonic aspirate samples during colonoscopy, suggests that this may be a better method for sample collection due to the parasite's irregular shedding in Blastocystis-infected stools. Patients with IBS infected with parasite showed an increase in the interleukin levels demonstrate that Blastocystis does have an effect in the immune system.

The Majorana Project

ScienceCinema

Orrell, John; Hoppe, Eric

2018-01-26

Working as part of a collaborative team, PNNL is bringing its signature capability in ultra-low-level detection to help search for a rare form of radioactive decay-never before detected-called "neutrinoless double beta decay" in germanium. If observed, it would demonstrate neutrinos are Majorana-type particles. This discovery would show neutrinos are unique among fundamental particles, having a property whereby the matter and anti-matter version of this particle are indistinguishable. Physicist John L. Orrell explains how they rely on the Shallow Underground Laboratory to conduct the research.

Ground-water quality in the southeastern Sacramento Valley aquifer, California, 1996

USGS Publications Warehouse

Milby Dawson, Barbara J.

2001-01-01

In 1996, the U.S. Geological Survey sampled 29 domestic wells and 2 monitoring wells in the southeastern Sacramento Valley as part of the U.S. Geological Survey's National Water-Quality Assessment (NAWQA) Program. This area, designated as the NAWQA Sacramento subunit study area, was chosen because it had the largest amount of ground-water use in the Sacramento River Basin. The Sacramento subunit study area is about 4,400 square kilometers and includes intense agricultural and urban development. The wells sampled ranged from 14.9 to 79.2 meters deep. Ground-water samples from 31 wells were analyzed for 6 field measurements, 14 inorganic constituents, 6 nutrient constituents, organic carbon, 86 pesticides, 87 volatile organic compounds, tritium (hydrogen-3), radon-222, deuterium (hydrogen-2), and oxygen-18. Nitrate levels were lower than the 2000 drinking-water standards in all but one well, but many detections were in the range that indicated an effect by human activities on ground-water quality. Radon was detected in all wells, and was measured at levels above the proposed Federal 2000 maximum contaminant level in 90 percent of the wells. Five pesticides and one pesticide degradation product were detected in ground-water samples and concentrations were below 2000 drinking-water standards. All pesticides detected during this study have been used in the Sacramento Valley. Thirteen volatile organic compounds were detected in ground water. One detection of trichloroethene was above Federal 2000 drinking-water standards, and another, tetrachloromethane, was above California 1997 drinking-water standards; both occurred in a well that had eight volatile organic compound detections and is near a known source of ground-water contamination. Pesticides and volatile organic compounds were detected in agricultural and urban areas; both pesticides and volatile organic compounds were detected at a higher frequency in urban wells. Ground-water chemistry indicates that natural processes and human activities are affecting ground-water quality in the upper part of the southeastern Sacramento Valley aquifer. The factors identified as having an influence on ground-water quality were redox condition in the aquifer, depth within the aquifer, and land use overlying the aquifer. Nitrate concentra-tions showed a statistical correlation with each of these factors. Detections of pesticides and volatile organic compounds were too few to compare concentrations with the various factors, but the types of synthetic compounds detected were consistent with the sur-rounding land use. Sixty-one percent of the wells sampled in this study showed the effect of human activities on ground-water quality in the form of a nitrate concentration over 3 milligrams per liter or a detection of a pesticide or volatile organic compound. In general, the water quality in the southeastern Sacramento Valley aquifer was found suitable for most uses.

Inkjet-printed gold nanoparticle surfaces for the detection of low molecular weight biomolecules by laser desorption/ionization mass spectrometry.

PubMed

Marsico, Alyssa L M; Creran, Brian; Duncan, Bradley; Elci, S Gokhan; Jiang, Ying; Onasch, Timothy B; Wormhoudt, Joda; Rotello, Vincent M; Vachet, Richard W

2015-11-01

Effective detection of low molecular weight compounds in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) is often hindered by matrix interferences in the low m/z region of the mass spectrum. Here, we show that monolayer-protected gold nanoparticles (AuNPs) can serve as alternate matrices for the very sensitive detection of low molecular weight compounds such as amino acids. Amino acids can be detected at low fmol levels with minimal interferences by properly choosing the AuNP deposition method, density, size, and monolayer surface chemistry. By inkjet-printing AuNPs at various densities, we find that AuNP clusters are essential for obtaining the greatest sensitivity. Graphical Abstract ᅟ.

Ultrasensitive aptamer-based protein detection via a dual amplified biocatalytic strategy

PubMed Central

Xiang, Yun; Zhang, Yuyong; Qian, Xiaoqing; Chai, Yaqin; Wang, Joseph; Yuan, Ruo

2010-01-01

We present an ultrasensitive aptasensor for electronic monitoring of proteins through a dual amplified strategy in this paper. The target protein thrombin is sandwiched between an electrode surface confined aptamer and an aptamer-enzyme-carbon nanotube bioconjugate. The analytical signal amplification is achieved by coupling the signal amplification nature of multiple enzymes with the biocatalytic signal enhancement of redox-recycling. Our novel dramatic signal amplification strategy, with a detection limit of 8.3 fM, shows about 4 orders of magnitude improvement in sensitivity for thrombin detection compared to other universal single enzyme-based assay. This makes our approach an attractive alternative to other common PCR-based signal amplification in ultralow level of protein detection. PMID:20452761

Single Nanochannel-Aptamer-Based Biosensor for Ultrasensitive and Selective Cocaine Detection.

PubMed

Wang, Jian; Hou, Jue; Zhang, Huacheng; Tian, Ye; Jiang, Lei

2018-01-17

Ultrasensitive and selective detection of molecules at nano or sub-nanomolar level is very important for many areas such as early diagnosis and drug testing. Herein, we report a high-sensitive cocaine sensor based on a single nanochannel coupled with DNA aptamers. The single nanochannel-aptamer-based biosensor can recognize cocaine molecules with an excellent sensitivity and good selectivity. A linear relationship between target cocaine concentration and output ionic current is obtained in a wide concentration range of cocaine from 1 nM to 10 μM. The cocaine sensor also shows a detection limit down to 1 nM. This study provides a new avenue to develop new nanochannel-aptamer-based biosensors for rapid and ultratrace detection of a variety of illicit drugs.

Detection of needle to nerve contact based on electric bioimpedance and machine learning methods.

PubMed

Kalvoy, Havard; Tronstad, Christian; Ullensvang, Kyrre; Steinfeldt, Thorsten; Sauter, Axel R

2017-07-01

In an ongoing project for electrical impedance-based needle guidance we have previously showed in an animal model that intraneural needle positions can be detected with bioimpedance measurement. To enhance the power of this method we in this study have investigated whether an early detection of the needle only touching the nerve also is feasible. Measurement of complex impedance during needle to nerve contact was compared with needle positions in surrounding tissues in a volunteer study on 32 subjects. Classification analysis using Support-Vector Machines demonstrated that discrimination is possible, but that the sensitivity and specificity for the nerve touch algorithm not is at the same level of performance as for intra-neuralintraneural detection.

Texture metric that predicts target detection performance

NASA Astrophysics Data System (ADS)

Culpepper, Joanne B.

2015-12-01

Two texture metrics based on gray level co-occurrence error (GLCE) are used to predict probability of detection and mean search time. The two texture metrics are local clutter metrics and are based on the statistics of GLCE probability distributions. The degree of correlation between various clutter metrics and the target detection performance of the nine military vehicles in complex natural scenes found in the Search_2 dataset are presented. Comparison is also made between four other common clutter metrics found in the literature: root sum of squares, Doyle, statistical variance, and target structure similarity. The experimental results show that the GLCE energy metric is a better predictor of target detection performance when searching for targets in natural scenes than the other clutter metrics studied.

a New Object-Based Framework to Detect Shodows in High-Resolution Satellite Imagery Over Urban Areas

NASA Astrophysics Data System (ADS)

Tatar, N.; Saadatseresht, M.; Arefi, H.; Hadavand, A.

2015-12-01

In this paper a new object-based framework to detect shadow areas in high resolution satellite images is proposed. To produce shadow map in pixel level state of the art supervised machine learning algorithms are employed. Automatic ground truth generation based on Otsu thresholding on shadow and non-shadow indices is used to train the classifiers. It is followed by segmenting the image scene and create image objects. To detect shadow objects, a majority voting on pixel-based shadow detection result is designed. GeoEye-1 multi-spectral image over an urban area in Qom city of Iran is used in the experiments. Results shows the superiority of our proposed method over traditional pixel-based, visually and quantitatively.

Automatic temporal segment detection via bilateral long short-term memory recurrent neural networks

NASA Astrophysics Data System (ADS)

Sun, Bo; Cao, Siming; He, Jun; Yu, Lejun; Li, Liandong

2017-03-01

Constrained by the physiology, the temporal factors associated with human behavior, irrespective of facial movement or body gesture, are described by four phases: neutral, onset, apex, and offset. Although they may benefit related recognition tasks, it is not easy to accurately detect such temporal segments. An automatic temporal segment detection framework using bilateral long short-term memory recurrent neural networks (BLSTM-RNN) to learn high-level temporal-spatial features, which synthesizes the local and global temporal-spatial information more efficiently, is presented. The framework is evaluated in detail over the face and body database (FABO). The comparison shows that the proposed framework outperforms state-of-the-art methods for solving the problem of temporal segment detection.

Sonora exploratory study for the detection of wheat-leaf rust

NASA Technical Reports Server (NTRS)

Payne, R. W. (Principal Investigator)

1980-01-01

The applicability of LANDSAT remote sensing technology to the detection of a wheat-leaf-rust epidemic in Sonora, Mexico, during 1977 was investigated. LANDSAT data acquired during crop years 1975-76 and 1976-77 were clustered, classified, and analyzed in order to detect agricultural changes. Analysis of 1977 data indicates a significant proportion of the identified wheat is stressed (potentially rust-infected). Additional analyses show a significant increase in fallowing during the year, as well as a substantial decrease in reservoir levels in the Sonora agricultural region. Ground observations are required to substantiate these analyses. The possibility exists that heat-rust is not LANDSAT detectable and that the clusters identified as containing stressed signatures represent different varieties of wheat or perhaps nonwheat crops.

IUE's View of Callisto: Detection of an SO2 Absorption Correlated to Possible Torus Neutral Wind Alterations

NASA Technical Reports Server (NTRS)

Lane, Arthur L.; Domingue, Deborah L.

1997-01-01

Observations taken with the International Ultraviolet Explorer (IUE) detected a 0.28 micron absorption feature on Callisto's leading and Jupiter-facing hemispheres. This feature is similar to Europa's 0.28 micron feature, however it shows no correlation with magnetospheric ion bombardment. The strongest 0.28 micron signature is seen in the region containing the Valhalla impact. This absorption feature also shows some spatial correlation to possible neutral wind interactions, suggestive of S implantation (rather than S(sub x)) into Callisto's water ice surface, Indications of possible temporal variations (on the 10% level) are seen at other wavelengths between the 1984-1986 and the 1996 observations.

Pulmonary Paragonimiasis: The Detection of a Worm Migration Track as a Diagnostic Clue for Uncertain Eosinophilic Pleural Effusion.

PubMed

Akaba, Tomohiro; Takeyama, Kiyoshi; Toriyama, Midori; Kubo, Ayako; Mizobuchi, Rie; Yamada, Takeshi; Tagaya, Etsuko; Kondo, Mitsuko; Sakai, Shuji; Tamaoki, Jun

2016-01-01

A 38-year-old woman with sustained right chest pain was referred to our hospital. She showed pleural effusion and peripheral blood eosinophilia. Thoracentesis revealed eosinophilic pleural effusion in which the smear, culture and cytological examinations were all negative. Although she had no notable dietary history, chest CT revealed linear opacities, which suggested the migration tracks of paragonimiasis. The diagnosis was confirmed using enzyme-linked immunosorbent assays, which showed elevated Paragonimus westermani and Paragonimus miyazakii antibody levels. After the initiation of praziquantel therapy, all clinical findings were promptly improved. The detection of a migration track may therefore be useful in the diagnosis of paragonimiasis.

Detection of trace microcystin-LR on a 20 MHz QCM sensor coated with in situ self-assembled MIPs.

PubMed

He, Hao; Zhou, Lianqun; Wang, Yi; Li, Chuanyu; Yao, Jia; Zhang, Wei; Zhang, Qingwen; Li, Mingyu; Li, Haiwen; Dong, Wen-fei

2015-01-01

A 20 MHz quartz crystal microbalance (QCM) sensor coated with in situ self-assembled molecularly imprinted polymers (MIPs) was presented for the detection of trace microcystin-LR (MC-LR) in drinking water. The sensor performance obtained using the in situ self-assembled MIPs was compared with traditionally synthesized MIPs on 20 MHz and normal 10 MHz QCM chip. The results show that the response increases by more than 60% when using the in situ self-assembly method compared using the traditionally method while the 20 MHz QCM chip provides four-fold higher response than the 10 MHz one. Therefore, the in situ self-assembled MIPs coated on a high frequency QCM chip was used in the sensor performance test to detect MC-LR in tap water. It showed a limit of detection (LOD) of 0.04 nM which is lower than the safety guideline level (1 nM MC-LR) of drinking water in China. The low sensor response to other analogs indicated the high specificity of the sensor to MC-LR. The sensor showed high stability and low signal variation less than 2.58% after regeneration. The lake water sample analysis shows the sensor is possible for practical use. The combination of the higher frequency QCM with the in situ self-assembled MIPs provides a good candidate for the detection of other small molecules. Copyright © 2014 Elsevier B.V. All rights reserved.

The influence of FMRI lie detection evidence on juror decision-making.

PubMed

McCabe, David P; Castel, Alan D; Rhodes, Matthew G

2011-01-01

In the current study, we report on an experiment examining whether functional magnetic resonance imaging (fMRI) lie detection evidence would influence potential jurors' assessment of guilt in a criminal trial. Potential jurors (N = 330) read a vignette summarizing a trial, with some versions of the vignette including lie detection evidence indicating that the defendant was lying about having committed the crime. Lie detector evidence was based on evidence from the polygraph, fMRI (functional brain imaging), or thermal facial imaging. Results showed that fMRI lie detection evidence led to more guilty verdicts than lie detection evidence based on polygraph evidence, thermal facial imaging, or a control condition that did not include lie detection evidence. However, when the validity of the fMRI lie detection evidence was called into question on cross-examination, guilty verdicts were reduced to the level of the control condition. These results provide important information about the influence of lie detection evidence in legal settings. Copyright © 2011 John Wiley & Sons, Ltd.

Machine Learning Methods for Attack Detection in the Smart Grid.

PubMed

Ozay, Mete; Esnaola, Inaki; Yarman Vural, Fatos Tunay; Kulkarni, Sanjeev R; Poor, H Vincent

2016-08-01

Attack detection problems in the smart grid are posed as statistical learning problems for different attack scenarios in which the measurements are observed in batch or online settings. In this approach, machine learning algorithms are used to classify measurements as being either secure or attacked. An attack detection framework is provided to exploit any available prior knowledge about the system and surmount constraints arising from the sparse structure of the problem in the proposed approach. Well-known batch and online learning algorithms (supervised and semisupervised) are employed with decision- and feature-level fusion to model the attack detection problem. The relationships between statistical and geometric properties of attack vectors employed in the attack scenarios and learning algorithms are analyzed to detect unobservable attacks using statistical learning methods. The proposed algorithms are examined on various IEEE test systems. Experimental analyses show that machine learning algorithms can detect attacks with performances higher than attack detection algorithms that employ state vector estimation methods in the proposed attack detection framework.

Automated detection of red lesions from digital colour fundus photographs.

PubMed

Jaafar, Hussain F; Nandi, Asoke K; Al-Nuaimy, Waleed

2011-01-01

Earliest signs of diabetic retinopathy, the major cause of vision loss, are damage to the blood vessels and the formation of lesions in the retina. Early detection of diabetic retinopathy is essential for the prevention of blindness. In this paper we present a computer-aided system to automatically identify red lesions from retinal fundus photographs. After pre-processing, a morphological technique was used to segment red lesion candidates from the background and other retinal structures. Then a rule-based classifier was used to discriminate actual red lesions from artifacts. A novel method for blood vessel detection is also proposed to refine the detection of red lesions. For a standarised test set of 219 images, the proposed method can detect red lesions with a sensitivity of 89.7% and a specificity of 98.6% (at lesion level). The performance of the proposed method shows considerable promise for detection of red lesions as well as other types of lesions.

Fast Detection of Airports on Remote Sensing Images with Single Shot MultiBox Detector

NASA Astrophysics Data System (ADS)

Xia, Fei; Li, HuiZhou

2018-01-01

This paper introduces a method for fast airport detection on remote sensing images (RSIs) using Single Shot MultiBox Detector (SSD). To our knowledge, this could be the first study which introduces an end-to-end detection model into airport detection on RSIs. Based on the common low-level features between natural images and RSIs, a convolution neural network trained on large amounts of natural images was transferred to tackle the airport detection problem with limited annotated data. To deal with the specific characteristics of RSIs, some related parameters in the SSD, such as the scales and layers, were modified for more accurate and rapider detection. The experiments show that the proposed method could achieve 83.5% Average Recall at 8 FPS on RSIs with the size of 1024*1024. In contrast to Faster R-CNN, an improvement on AP and speed could be obtained.

Discrimination of fungal infections on grape berries via spectral signatures

NASA Astrophysics Data System (ADS)

Molitor, Daniel; Griesser, Michaela; Schütz, Erich; Khuen, Marie-Therese; Schefbeck, Christa; Ronellenfitsch, Franz Kai; Schlerf, Martin; Beyer, Marco; Schoedl-Hummel, Katharina; Anhalt, Ulrike; Forneck, Astrid

2016-04-01

The fungal pathogens Botrytis cinerea and Penicillium expansum are causing economic damages on grapevine worldwide. Especially the simultaneous occurrence of both often results in off-flavours highly threatening wine quality. For the classification of grape quality as well as for the determination of targeted enological treatments, the knowledge of the level of fungal attack is of highest interest. However, visual assessment and pathogen discrimination are cost-intensive. Consequently, a pilot laboratory study aimed at (i) detecting differences in spectral signatures between grape berry lots with different levels of infected berries (B. cinerea and/or P. expansum) and (ii) detecting links between spectral signatures and biochemical as well as quantitative molecular markers for fungal attack. To this end, defined percentages (infection levels) of table grape berries were inoculated with fungal spore suspensions. Spectral measurements were taken using a FieldSpec 3 Max spectroradiometer (ASD Inc., Boulder/Colorado, USA) in regular intervals after inoculation. In addition, fungal attack was determined enzymatically) and quantitatively (real-time PCR). In addition, gluconic acid concentrations (as a potential markers for fungal attack) were determined photometrically. Results indicate that based on spectral signatures, a discrimination of P. expansum and B. cinerea infections as well as of different B. cinerea infection levels is possible. Real-time PCR analyses, detecting DNA levels of both fungi, showed yet a low detection level. Whereas the gluconic acid concentrations turned out to be specific for the two fungi tested (B. cinerea vs. P. expansum) and thus may serve as a differentiating biochemical marker. Correlation analyses between spectral measurements and biological data (gluconic acid concentrations, fungi DNA) as well as further common field and laboratory trials are targeted.

Calculating the ankylosing spondylitis disease activity score if the conventional c-reactive protein level is below the limit of detection or if high-sensitivity c-reactive protein is used: an analysis in the DESIR cohort.

PubMed

Machado, Pedro; Navarro-Compán, Victoria; Landewé, Robert; van Gaalen, Floris A; Roux, Christian; van der Heijde, Désirée

2015-02-01

The Ankylosing Spondylitis Disease Activity Score (ASDAS) is a composite measure of disease activity in axial spondyloarthritis. The aims of this study were to determine the most appropriate method for calculating the ASDAS using the C-reactive protein (CRP) level when the conventional CRP level was below the limit of detection, to determine how low CRP values obtained by high-sensitivity CRP (hsCRP) measurement influence ASDAS-CRP results, and to test agreement between different ASDAS formulae. Patients with axial spondyloarthritis who had a conventional CRP level below the limit of detection (5 mg/liter) were selected (n = 257). The ASDAS–conventional CRP with 11 different imputations for the conventional CRP value (range 0–5 mg/liter, at 0.5-mg/liter intervals) was calculated. The ASDAS-hsCRP and ASDAS using the erythrocyte sedimentation rate (ESR) were also calculated. Agreement between the ASDAS formulae was tested. The ASDAS-hsCRP showed better agreement with the ASDAS-CRP calculated using the conventional CRP imputation values of 1.5 and 2.0 mg/liter and with the ASDAS-ESR than with other imputed formulae. Disagreement occurred mainly in lower disease activity states (inactive/moderate disease activity). When the CRP value was <2 mg/liter, the resulting ASDAS-CRP scores may have been inappropriately low. When the conventional CRP level is below the limit of detection or when the hsCRP level is <2 mg/liter, the constant value of 2 mg/liter should be used to calculate the ASDAS-CRP score. There is good agreement between the ASDAS-hsCRP and ASDAS-ESR; however, formulae are not interchangeable.

Pico-level DNA sensing by hetero-polymetalate, Na10{Dy2W10O30(µ-S)6}·80H2O, cluster

NASA Astrophysics Data System (ADS)

Dutta, Taposhree; Ganguly, Jhuma; Sarkar, Sabyasachi

2018-04-01

The polyoxometalate dysprosium cluster, (Dy-S-W POM) , Na10[Dy2W10O30(µ-S)6]·80H2O, shows remarkable dsDNA denaturation property. In the presence of 0.22 µmol of this Dy-S-W POM, the melting temperature (Tm) of calf-thymus (CT) dsDNA is decreased to 62.35 °C. Dy-S-W POM shows bleaching of methylene blue (MB). Addition of CT-DNA in the MB bleached solution of Dy-S-W POM apparently intercalates MB. Such trapped MB by CT-DNA responds to its re-oxidation by elemental sulfur formed in the bleaching process involving Dy-S-W POM. This reduction-oxidation property of MB with Dy-S-W POM led to the detection of pico (13.20 pmol) level of DNA even by naked eye, which will be helpful for rapid trace DNA detection in forensic science and DNA-related diagnostics, complimenting time-consuming sophisticated methodology.

A turn-on supramolecular fluorescent probe for sensing benzimidazole fungicides and its application in living cell imaging

NASA Astrophysics Data System (ADS)

Tang, Qing; Zhang, Jing; Sun, Tao; Wang, Cheng-Hui; Huang, Ying; Zhou, Qingdi; Wei, Gang

2018-02-01

A cucurbit[8]uril-based turn-on supramolecular fluorescent probe between cucurbit[8]uril (Q[8]) and pyronine Y (PyY) (designated 2PyY@Q[8]) in acidic aqueous solution showed a remarkable fluorescence 'turn-on' response to benzimidazole fungicides such as thiabendazole, fuberidazole and carbendazim. The 2PyY@Q[8] fluorescent probe can be used to detect benzimidazole fungicides with high sensitivity and selectivity with a detection limit of 10- 8 mol/L. A good linear relationship of emission intensity at 580 nm for benzimidazole fungicides at concentrations of 0.4-5.0 μmol/L was observed. The proposed sensing mechanism was investigated using 1H NMR spectroscopy combined with density functional theory calculations at the B3LYP/6-31G(d) level. The cell imaging study showed that the 2PyY@Q[8] complex could be used to image benzimidazole fungicide in prostate cancer (PC3) cells, which may help to elucidate relevant biological processes at the molecular level.

Two cases of erosive oral lichen planus with autoantibodies to desmoglein 3.

PubMed

Muramatsu, Ken; Nishie, Wataru; Natsuga, Ken; Fujita, Yasuyuki; Iwata, Hiroaki; Yamada, Tamaki; Yamashita, Emi; Asaka, Takuya; Shimizu, Hiroshi

2016-11-01

Oral lichen planus (OLP) is a chronic inflammatory disorder of the oral mucosa of unknown etiology. Clinically, the erosive type of OLP (erosive OLP) can show features similar to those of pemphigus vulgaris (PV), an autoimmune blistering disorder in which desmoglein (Dsg)3 is targeted. In addition to clinical and histopathological findings, immunological studies, including direct immunofluorescence (IF), indirect IF and enzyme-linked immunosorbent assay (ELISA) that detect autoantibodies to Dsg3, are helpful in differentiating erosive OLP from PV. Here, we show two cases of erosive OLP with autoantibodies to Dsg3. Patient 1 was a 68-year-old woman with chronic erosions of the oral mucosa, in which elevated levels of immunoglobulin (Ig)G autoantibodies to Dsg1 and Dsg3 were detected by ELISA. Patient 2 was an 85-year-old woman with white striae with erosions on the lateral sides of the buccal mucosa with elevated levels of IgG autoantibodies to Dsg3 detected by ELISA. Histopathological findings from both cases showed lichenoid dermatitis, and both direct and indirect IF showed no tissue-bound IgG autoantibodies. From these findings, the diagnosis of erosive OLP was made. Immunological assays revealed both cases to have IgG-directing calcium-independent linear epitopes on Dsg3, which are suggestive of non-pathogenic autoantibodies. In addition, autoantibodies to Dsg3 in patient 2 reacted with a prosequence-possessing precursor form of Dsg3 but not with the mature form of the molecule. The present study suggests that erosive OLP may develop anti-Dsg3 autoantibodies, which should be carefully assessed. © 2016 Japanese Dermatological Association.

Personal exposure to aerosolized red tide toxins (brevetoxins).

PubMed

Cheng, Yung Sung; Zhou, Yue; Naar, Jerome; Irvin, C Mitch; Su, Wei-Chung; Fleming, Lora E; Kirkpatrick, Barbara; Pierce, Richard H; Backer, Lorraine C; Baden, Daniel G

2010-06-01

Florida red tides occur annually in the Gulf of Mexico from blooms of the marine dinoflagellate, Karenia brevis, which produces highly potent natural polyether toxins, brevetoxins. Several epidemiologic studies have demonstrated that human exposure to red tide aerosol could result in increased respiratory symptoms. Environmental monitoring of aerosolized brevetoxins was performed using a high-volume sampler taken hourly at fixed locations on Siesta Beach, Florida. Personal exposure was monitored using personal air samplers and taking nasal swab samples from the subjects who were instructed to spend 1 hr on Sarasota Beach during two sampling periods of an active Florida red tide event in March 2005, and in May 2008 when there was no red tide. Results showed that the aerosolized brevetoxins from the personal sampler were in modest agreement with the environmental concentration taken from a high-volume sampler. Analysis of nasal swab samples for brevetoxins demonstrated 68% positive samples in the March 2005 sampling period when air concentrations of brevetoxins were between 50 to 120 ng/m(3) measured with the high-volume sampler. No swab samples showed detectable levels of brevetoxins in the May 2008 study, when all personal samples were below the limit of detection. However, there were no statistical correlations between the amounts of brevetoxins detected in the swab samples with either the environmental or personal concentration. Results showed that the personal sample might provide an estimate of individual exposure level. Nasal swab samples showed that brevetoxins indeed were inhaled and deposited in the nasal passage during the March 2005 red tide event.

Application of Monoclonal Antibodies to Detect and Compare the Levels of Streptococcus mutans in Adolescents Undergoing Orthodontic Treatment with Those Not Undergoing Treatment.

PubMed

Kim, Jae Hwan; Kim, Mi Ah; Kim, Jae Gon

2016-10-01

The purpose of this study was to detect Streptococcus mutans by using monoclonal antibodies (mAbs) against S. mutans that cause dental caries and compare the levels of the bacterium between the saliva of adolescents undergoing orthodontic treatment (OT) and those not undergoing treatment (NT). Saliva samples, collected from 25 OT adolescents (with a mean age of 12.84 years) and 25 NT adolescents (mean age of 12.4 years), were analyzed by Dentocult-SM and enzyme-linked immunosorbent assay using mAbs against Ag I/II (ckAg I/II) and GTF B (ckGTF B), GTF C (ckGTF C), and GTF D (ckGTF D) of S. mutans. The DMFT index was slightly higher in the OT group (5.12 in OT and 4.96 in NT) and the level of S. mutans (≥10 5 CFU/mL) was higher in OT (72%) than in NT (56%). The detected levels of ckAg I/II, ckGTF B, ckGTF C, and ckGTF D were slightly higher in OT than in NT. The results of this study indicate that use of mAbs against S. mutans yields sensitive detection for the bacterium in saliva samples and shows that it has a reliable connection to the number of S. mutans and decayed, missing, filled teeth (DMFT), suggesting that the levels of S. mutans in saliva can be defined and compared by the application of the mAbs.

Resonator graphene microfluidic antenna (RGMA) for blood glucose detection

NASA Astrophysics Data System (ADS)

Jizat, Noorlindawaty Md.; Mohamad, Su Natasha; Ishak, Muhammad Ikman

2017-09-01

Graphene is capable of highly sensitive analyte detection due to its nanoscale nature. Here we show a resonator graphene microfluidic antenna (RGMA) is used to detect the dielectric properties of aqueous glucose solution which represent the glucose level in blood. Simulation verified the high sensitivity of proposed RGMA made with aqueous glucose solutions at different concentrations. The RGMA yielded a sensor sensitivity of 0.1882GHz/mgml-1 as plotted from the slope of the linear fit from the result averages in S11 and S21 parameter, respectively. This results indicate that the proposed resonator antenna achieves high sensitivity and linear to the changes of glucose concentration.

Using Sequence Diagrams to Detect Communication Problems Between Systems

NASA Technical Reports Server (NTRS)

Lindvall, Mikael; Ackermann, Chris; Stratton, William C.; Sibol, Deane E.; Ray, Arnab; Yonkwa, Lyly; Kresser, Jan; Godfrey, Sally H.; Knodel, Jens

2008-01-01

Many software systems are evolving complex system of systems (SoS) for which inter-system communication is both mission-critical and error-prone. Such communication problems ideally would be detected before deployment. In a NASA-supported Software Assurance Research Program (SARP) project, we are researching a new approach addressing such problems. In this paper, we show that problems in the communication between two systems can be detected by using sequence diagrams to model the planned communication and by comparing the planned sequence to the actual sequence. We identify different kinds of problems that can be addressed by modeling the planned sequence using different level of abstractions.

Automatic on-line detection system design research on internal defects of metal materials based on optical fiber F-P sensing technology

NASA Astrophysics Data System (ADS)

Xia, Liu; Shan, Ning; Chao, Ban; Caoshan, Wang

2016-10-01

Metal materials have been used in aerospace and other industrial fields widely because of its excellent characteristics, so its internal defects detection is very important. Ultrasound technology is used widely in the fields of nondestructive detection because of its excellent characteristic. But the conventional detection instrument for ultrasound, which has shortcomings such as low intelligent level and long development cycles, limits its development. In this paper, the theory of ultrasound detection is analyzed. A computational method of the defects distributional position is given. The non-contact type optical fiber F-P interference cavity structure is designed and the length of origin cavity is given. The real-time on-line ultrasound detecting experiment devices for internal defects of metal materials is established based on the optical fiber F-P sensing system. The virtual instrument of automation ultrasound detection internal defects is developed based on LabVIEW software and the experimental study is carried out. The results show that this system can be used in internal defect real-time on-line locating of engineering structures effectively. This system has higher measurement precision. Relative error is 6.7%. It can be met the requirement of engineering practice. The system is characterized by simple operation, easy realization. The software has a friendly interface, good expansibility, and high intelligent level.

Detecting Payload Attacks on Programmable Logic Controllers (PLCs)

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

Yang, Huan

Programmable logic controllers (PLCs) play critical roles in industrial control systems (ICS). Providing hardware peripherals and firmware support for control programs (i.e., a PLC’s “payload”) written in languages such as ladder logic, PLCs directly receive sensor readings and control ICS physical processes. An attacker with access to PLC development software (e.g., by compromising an engineering workstation) can modify the payload program and cause severe physical damages to the ICS. To protect critical ICS infrastructure, we propose to model runtime behaviors of legitimate PLC payload program and use runtime behavior monitoring in PLC firmware to detect payload attacks. By monitoring themore » I/O access patterns, network access patterns, as well as payload program timing characteristics, our proposed firmware-level detection mechanism can detect abnormal runtime behaviors of malicious PLC payload. Using our proof-of-concept implementation, we evaluate the memory and execution time overhead of implementing our proposed method and find that it is feasible to incorporate our method into existing PLC firmware. In addition, our evaluation results show that a wide variety of payload attacks can be effectively detected by our proposed approach. The proposed firmware-level payload attack detection scheme complements existing bumpin- the-wire solutions (e.g., external temporal-logic-based model checkers) in that it can detect payload attacks that violate realtime requirements of ICS operations and does not require any additional apparatus.« less

Ultrasensitive Detection of Ebola Virus Oligonucleotide Based on Upconversion Nanoprobe/Nanoporous Membrane System.

PubMed

Tsang, Ming-Kiu; Ye, WeiWei; Wang, Guojing; Li, Jingming; Yang, Mo; Hao, Jianhua

2016-01-26

Ebola outbreaks are currently of great concern, and therefore, development of effective diagnosis methods is urgently needed. The key for lethal virus detection is high sensitivity, since early-stage detection of virus may increase the probability of survival. Here, we propose a luminescence scheme of assay consisting of BaGdF5:Yb/Er upconversion nanoparticles (UCNPs) conjugated with oligonucleotide probe and gold nanoparticles (AuNPs) linked with target Ebola virus oligonucleotide. As a proof of concept, a homogeneous assay was fabricated and tested, yielding a detection limit at picomolar level. The luminescence resonance energy transfer is ascribed to the spectral overlapping of upconversion luminescence and the absorption characteristics of AuNPs. Moreover, we anchored the UCNPs and AuNPs on a nanoporous alumina (NAAO) membrane to form a heterogeneous assay. Importantly, the detection limit was greatly improved, exhibiting a remarkable value at the femtomolar level. The enhancement is attributed to the increased light-matter interaction throughout the nanopore walls of the NAAO membrane. The specificity test suggested that the nanoprobes were specific to Ebola virus oligonucleotides. The strategy combining UCNPs, AuNPs, and NAAO membrane provides new insight into low-cost, rapid, and ultrasensitive detection of different diseases. Furthermore, we explored the feasibility of clinical application by using inactivated Ebola virus samples. The detection results showed great potential of our heterogeneous design for practical application.

Chandra Observations of Magnetic White Dwarfs and Their Theoretical Implications

NASA Technical Reports Server (NTRS)

Musielak, Z. E.; Noble, M.; Porter, J. G.; Winget, D. E.; Six, N. Frank (Technical Monitor)

2002-01-01

Observations of cool DA and DB white dwarfs have not yet been successful in detecting coronal X-ray emission but observations of late-type dwarfs and giants show that coronae are common for these stars. To produce coronal X-rays, a star must have dynamo-generated surface magnetic fields and a well-developed convection zone. There is strong observational evidence that the DA star LHS 1038 and the DB star GD 358 have weak and variable surface magnetic fields. Since these fields are likely to be generated by dynamo action and since both stars have well-developed convection zones, theory predicts detectable levels of coronal X-rays from these white dwarfs. However, we present analysis of Chandra observations of both stars showing no detectable X-ray emission. The derived upper limits for the X-ray fluxes provide strong constraints on theories of formation of coronae around magnetic white dwarfs.

Changes in the vibration sensitivity and pressure pain thresholds in patients with burning mouth syndrome

PubMed Central

Ferreira, Natália dos Reis; Janini, Maria Elisa Rangel

2018-01-01

Objective To investigate the presence of changes in vibration detection and pressure pain threshold in patients with burning-mouth syndrome (BMS). Design of the study Case-control study. The sample was composed of 30 volunteers, 15 with BMS and 15 in the control group. The pressure-pain threshold (PPT) and vibration-detection threshold (VDT) were examined. The clinical evaluation was complemented with the McGill Pain Questionnaire (MPQ), Douleur Neuropathique 4 (DN4) and Beck Depression and Anxiety Inventories (BDI and BAI, respectively). Results BMS subjects showed a statistically significant higher PPT in the tongue (p = 0.002), right (p = 0.001) and left (p = 0.004) face, and a significant reduction of the VDT in the tongue (p = 0.013) and right face (p = 0.030). Significant differences were also found when comparing the PPT and the VDT of distinct anatomical areas. However, a significant interaction (group × location) was only for the PPT. BMS subjects also showed significantly higher levels of depression (p = 0.01), as measured by the BDI, compared to controls; and a significant inverse correlation between the VDT in the left face and anxiety levels was detected. Conclusions The study of somatosensory changes in BMS and its correlations with the clinical features as well as the levels of anxiety and depression expands current understanding of the neuropathic origin and the possible contribution of psychogenic factors related to this disease. PMID:29782537

Mapping Health Data: Improved Privacy Protection With Donut Method Geomasking

PubMed Central

Hampton, Kristen H.; Fitch, Molly K.; Allshouse, William B.; Doherty, Irene A.; Gesink, Dionne C.; Leone, Peter A.; Serre, Marc L.; Miller, William C.

2010-01-01

A major challenge in mapping health data is protecting patient privacy while maintaining the spatial resolution necessary for spatial surveillance and outbreak identification. A new adaptive geomasking technique, referred to as the donut method, extends current methods of random displacement by ensuring a user-defined minimum level of geoprivacy. In donut method geomasking, each geocoded address is relocated in a random direction by at least a minimum distance, but less than a maximum distance. The authors compared the donut method with current methods of random perturbation and aggregation regarding measures of privacy protection and cluster detection performance by masking multiple disease field simulations under a range of parameters. Both the donut method and random perturbation performed better than aggregation in cluster detection measures. The performance of the donut method in geoprivacy measures was at least 42.7% higher and in cluster detection measures was less than 4.8% lower than that of random perturbation. Results show that the donut method provides a consistently higher level of privacy protection with a minimal decrease in cluster detection performance, especially in areas where the risk to individual geoprivacy is greatest. PMID:20817785

Mapping health data: improved privacy protection with donut method geomasking.

PubMed

Hampton, Kristen H; Fitch, Molly K; Allshouse, William B; Doherty, Irene A; Gesink, Dionne C; Leone, Peter A; Serre, Marc L; Miller, William C

2010-11-01

A major challenge in mapping health data is protecting patient privacy while maintaining the spatial resolution necessary for spatial surveillance and outbreak identification. A new adaptive geomasking technique, referred to as the donut method, extends current methods of random displacement by ensuring a user-defined minimum level of geoprivacy. In donut method geomasking, each geocoded address is relocated in a random direction by at least a minimum distance, but less than a maximum distance. The authors compared the donut method with current methods of random perturbation and aggregation regarding measures of privacy protection and cluster detection performance by masking multiple disease field simulations under a range of parameters. Both the donut method and random perturbation performed better than aggregation in cluster detection measures. The performance of the donut method in geoprivacy measures was at least 42.7% higher and in cluster detection measures was less than 4.8% lower than that of random perturbation. Results show that the donut method provides a consistently higher level of privacy protection with a minimal decrease in cluster detection performance, especially in areas where the risk to individual geoprivacy is greatest.

Evaluation of camouflage effectiveness using hyperspectral images

NASA Astrophysics Data System (ADS)

Zavvartorbati, Ahmad; Dehghani, Hamid; Rashidi, Ali Jabar

2017-10-01

Recent advances in camouflage engineering have made it more difficult to detect targets. Assessing the effectiveness of camouflage against different target detection methods leads to identifying the strengths and weaknesses of camouflage designs. One of the target detection methods is to analyze the content of the scene using remote sensing hyperspectral images. In the process of evaluating camouflage designs, there must be comprehensive and efficient evaluation criteria. Three parameters were considered as the main factors affecting the target detection and based on these factors, camouflage effectiveness assessment criteria were proposed. To combine the criteria in the form of a single equation, the equation used in target visual search models was employed and for determining the criteria, a model was presented based on the structure of the computational visual attention systems. Also, in software implementations on the HyMap hyperspectral image, a variety of camouflage levels were created for the real targets in the image. Assessing the camouflage levels using the proposed criteria, comparing and analyzing the results can show that the provided criteria and model are effective for the evaluation of camouflage designs using hyperspectral images.

Occurrence of organotins in the Yangtze River and the Jialing River in the urban section of Chongqing, China.

PubMed

Gao, Jun-Min; Zhang, Ying; Guo, Jin-Song; Jin, Fen; Zhang, Ke

2013-05-01

The occurrence of organotins in the Yangtze River and the Jialing River in the urban section of Chongqing, China and their impact on drinking water waterworks are reported in this study. Water samples were extracted by solid-phase microextraction and measured using a gas chromatograph with mass spectrometer. The results showed that the rivers studied were polluted by both butyltins and phenyltins and that the butyltin species was the dominant pollutant. Butyltins, especially monobutyltin, were detected in all 18 sampling stations, and phenyltins were detected only in 11 sampling stations. Majority of the organotins were MBTs with concentrations varying from 27.3 to 1,145.8 ng Sn L(-1). Diphenyltin and dibutyltin were the second most common with the highest levels of 113.7 and 202.5 ng Sn L(-1), respectively. Monophenyltin, tributyltin, and triphenyltin had the lowest detection rates with concentration levels of 9.7, 161.8, and 37.2 ng Sn L(-1), respectively. Some of the organotins were also detected in drinking water waterworks, which posed a threat to the water quality of Chongqing.

Effect of processing on recovery and variability associated with immunochemical analytical methods for multiple allergens in a single matrix: sugar cookies.

PubMed

Khuda, Sefat; Slate, Andrew; Pereira, Marion; Al-Taher, Fadwa; Jackson, Lauren; Diaz-Amigo, Carmen; Bigley, Elmer C; Whitaker, Thomas; Williams, Kristina M

2012-05-02

Among the major food allergies, peanut, egg, and milk are the most common. The immunochemical detection of food allergens depends on various factors, such as the food matrix and processing method, which can affect allergen conformation and extractability. This study aimed to (1) develop matrix-specific incurred reference materials for allergen testing, (2) determine whether multiple allergens in the same model food can be simultaneously detected, and (3) establish the effect of processing on reference material stability and allergen detection. Defatted peanut flour, whole egg powder, and spray-dried milk were added to cookie dough at seven incurred levels before baking. Allergens were measured using five commercial enzyme-linked immunosorbent assay (ELISA) kits. All kits showed decreased recovery of all allergens after baking. Analytical coefficients of variation for most kits increased with baking time, but decreased with incurred allergen level. Thus, food processing negatively affects the recovery and variability of peanut, egg, and milk detection in a sugar cookie matrix when using immunochemical methods.

Assessment of two different types of sample for the early detection and isolation of thermophilic Campylobacter in broiler farms.

PubMed

Urdaneta, Saulo; Dolz, Roser; Cerdà-Cuéllar, Marta

2015-01-01

In order to assess the optimal method for the early detection and isolation of thermophilic Campylobacter in broilers at farm level, two types of samples were compared: caecal contents obtained by necropsy and cloacal swabs transported in charcoal Amies medium. The study was conducted in five batches of broilers from five different farms, where weekly samples (caecal contents and cloacal swabs) from 30 birds were obtained. Samples were plated onto selective agar (modified charcoal cefoperazone desoxycholate agar, mCCDA) for Campylobacter isolation. Four out of five batches were positive for Campylobacter. No marked differences in sensitivity of both sample types were observed. However, a higher percentage of positive birds were detected when cloacal swabs were used. The results show that cloacal swab samples are adequate, and in some cases even better than caecal samples for the early detection of Campylobacter in broiler flocks at farm level. Also, this sample avoids sacrificing birds to test Campylobacter, which not only allows saving time in sample collection, transportation and processing at the laboratory, but also improves bird welfare and cost of sampling.

An overheight vehicle bridge collision monitoring system using piezoelectric transducers

NASA Astrophysics Data System (ADS)

Song, G.; Olmi, C.; Gu, H.

2007-04-01

With increasing traffic volume follows an increase in the number of overheight truck collisions with highway bridges. The detection of collision impact and evaluation of the impact level is a critical issue in the maintenance of a concrete bridge. In this paper, an overheight collision detection and evaluation system is developed for concrete bridge girders using piezoelectric transducers. An electric circuit is designed to detect the impact and to activate a digital camera to take photos of the offending truck. Impact tests and a health monitoring test were conducted on a model concrete bridge girder by using three piezoelectric transducers embedded before casting. From the experimental data of the impact test, it can be seen that there is a linear relation between the output of sensor energy and the impact energy. The health monitoring results show that the proposed damage index indicates the level of damage inside the model concrete bridge girder. The proposed overheight truck-bridge collision detection and evaluation system has the potential to be applied to the safety monitoring of highway bridges.

Highly sensitive and selective dynamic light-scattering assay for TNT detection using p-ATP attached gold nanoparticle.

PubMed

Dasary, Samuel S R; Senapati, Dulal; Singh, Anant Kumar; Anjaneyulu, Yerramilli; Yu, Hongtao; Ray, Paresh Chandra

2010-12-01

TNT is one of the most commonly used nitro aromatic explosives for landmines of military and terrorist activities. As a result, there is an urgent need for rapid and reliable methods for the detection of trace amount of TNT for screenings in airport, analysis of forensic samples, and environmental analysis. Driven by the need to detect trace amounts of TNT from environmental samples, this article demonstrates a label-free, highly selective, and ultrasensitive para-aminothiophenol (p-ATP) modified gold nanoparticle based dynamic light scattering (DLS) probe for TNT recognition in 100 pico molar (pM) level from ethanol:acetonitile mixture solution. Because of the formation of strong π-donor-acceptor interaction between TNT and p-ATP, para-aminothiophenol attached gold nanoparticles undergo aggregation in the presence of TNT, which changes the DLS intensity tremendously. A detailed mechanism for significant DLS intensity change has been discussed. Our experimental results show that TNT can be detected quickly and accurately without any dye tagging in 100 pM level with excellent discrimination against other nitro compounds.

Anti-Müllerian hormone (AMH) profiles as a novel biomarker to evaluate the existence of a functional cryptorchid testis in Japanese Black calves.

PubMed

Kitahara, Go; El-Sheikh Ali, Hossam; Sato, Tomohiro; Kobayashi, Ikuo; Hemmi, Koichiro; Shirao, Yuka; Kamimura, Shunichi

2012-01-01

Anti-Müllerian hormone (AMH) and testosterone (T) profiles in blood were investigated before and after an hCG stimulation test to assess their sensitivity and specificity for the existence of a functional cryptorchid testis in Japanese Black calves. The hCG (3,000 IU) was administered on Day 0, and peripheral blood was collected on Days 0 (just before hCG injection), 5 and 7 in intact male calves (Intact; n=19), bilateral castrated calves (Castrated; n=17), unilateral cryptorchid calves, which abdominal testis could been extracted (Uni-crypto; n=9). Castration of a descended testis was carried in the Castrated and Uni-Crypto groups on Day -14. The AMH detectability and the optimum cut-off point for T levels using the receiver operating characteristic curve were verified to characterize the cryptorchid testis. AMH values on Day 0 were 21.1 ± 5.1 and 29.0 ± 7.5 ng/ml in the Intact and Uni-crypto groups, respectively (Mean ± SEM). AMH levels were under the detection limit in the Castrated group (i.e., < 0.006 ng/ml). T showed its peak levels on Day 5 in the Intact group (26.8 ± 4.2 ng/ml), while it remained low in the Castrated group (< 0.9 ng/ml) and did not show a significant difference in the Uni-crypto group. The detectable levels for AMH was 0.006 ng/ml, and the optimum cut-off point for T was 0.9 ng/ml; the sensitivity and specificity for evaluation of testicular descent into the scrotum were 1.0 for both the AMH and T levels. The detection rates in the Uni-crypto group using them were 1.0 and 0.57 for AMH on Day 0 and T on Days 5 or 7, respectively. In conclusion, plasma AMH profiles could be used as a novel biomarker to evaluate the existence of a functional cryptorchid testis in Japanese Black calves.

A Temporal Model of Level-Invariant, Tone-in-Noise Detection

ERIC Educational Resources Information Center

Berg, Bruce G.

2004-01-01

Level-invariant detection refers to findings that thresholds in tone-in-noise detection are unaffected by roving-level procedures that degrade energy cues. Such data are inconsistent with ideas that detection is based on the energy passed by an auditory filter. A hypothesis that detection is based on a level-invariant temporal cue is advanced.…

Multiplex enrichment quantitative PCR (ME-qPCR): a high-throughput, highly sensitive detection method for GMO identification.

PubMed

Fu, Wei; Zhu, Pengyu; Wei, Shuang; Zhixin, Du; Wang, Chenguang; Wu, Xiyang; Li, Feiwu; Zhu, Shuifang

2017-04-01

Among all of the high-throughput detection methods, PCR-based methodologies are regarded as the most cost-efficient and feasible methodologies compared with the next-generation sequencing or ChIP-based methods. However, the PCR-based methods can only achieve multiplex detection up to 15-plex due to limitations imposed by the multiplex primer interactions. The detection throughput cannot meet the demands of high-throughput detection, such as SNP or gene expression analysis. Therefore, in our study, we have developed a new high-throughput PCR-based detection method, multiplex enrichment quantitative PCR (ME-qPCR), which is a combination of qPCR and nested PCR. The GMO content detection results in our study showed that ME-qPCR could achieve high-throughput detection up to 26-plex. Compared to the original qPCR, the Ct values of ME-qPCR were lower for the same group, which showed that ME-qPCR sensitivity is higher than the original qPCR. The absolute limit of detection for ME-qPCR could achieve levels as low as a single copy of the plant genome. Moreover, the specificity results showed that no cross-amplification occurred for irrelevant GMO events. After evaluation of all of the parameters, a practical evaluation was performed with different foods. The more stable amplification results, compared to qPCR, showed that ME-qPCR was suitable for GMO detection in foods. In conclusion, ME-qPCR achieved sensitive, high-throughput GMO detection in complex substrates, such as crops or food samples. In the future, ME-qPCR-based GMO content identification may positively impact SNP analysis or multiplex gene expression of food or agricultural samples. Graphical abstract For the first-step amplification, four primers (A, B, C, and D) have been added into the reaction volume. In this manner, four kinds of amplicons have been generated. All of these four amplicons could be regarded as the target of second-step PCR. For the second-step amplification, three parallels have been taken for the final evaluation. After the second evaluation, the final amplification curves and melting curves have been achieved.

Soluble Axl is an accurate biomarker of cirrhosis and hepatocellular carcinoma development: results from a large scale multicenter analysis

PubMed Central

Dengler, Mirko; Staufer, Katharina; Huber, Heidemarie; Stauber, Rudolf; Bantel, Heike; Weiss, Karl Heinz; Starlinger, Patrick; Pock, Hannelore; Klöters-Plachky, Petra; Gotthardt, Daniel N.; Rauch, Peter; Lackner, Carolin; Stift, Judith; Brostjan, Christine; Gruenberger, Thomas; Kumada, Takashi; Toyoda, Hidenori; Tada, Toshifumi; Weiss, Thomas S.; Trauner, Michael; Mikulits, Wolfgang

2017-01-01

Patients with chronic liver disease (CLD) and cirrhosis are at high risk for hepatocellular carcinoma (HCC). Current diagnostic tools for HCC detection include imaging techniques and serum biomarkers such as α-fetoprotein (AFP). Yet, these methods are limited in sensitivity and specificity to accurately detect early HCC. Here we focused on the potential of soluble Axl (sAxl) as a biomarker in CLD patients by analyzing serum samples of 1067 patients and healthy controls from centers in Europe and Asia. We show that serum concentrations of sAxl were significantly increased at early (82.57 ng/mL) and later stages of HCC (114.50 ng/mL) as compared to healthy controls (40.15 ng/mL). Notably, no elevated sAxl levels were detected in patients with CLD including chronic viral hepatitis, autoimmune hepatitis, cholestatic liver disease, or non-alcoholic fatty liver disease versus healthy controls. Furthermore, sAxl did not rise in liver adenomas or cholangiocarcinoma (CCA). Yet, patients with advanced fibrosis (F3) or cirrhosis (F4) showed enhanced sAxl concentrations (F3: 54.67 ng/mL; F4: 94.74 ng/mL). Hepatic myofibroblasts exhibited an increased release of sAxl, suggesting that elevated sAxl levels arise from these cells during fibrosis. Receiver operating characteristic curve analysis of sAxl displayed a strongly increased sensitivity and specificity to detect both cirrhosis (80.8%/92.0%) and HCC (83.3%/86.7%) with an area under the curve of 0.935/0.903 as compared to AFP. In conclusion, sAxl shows high diagnostic accuracy at early stage HCC as well as cirrhosis, thereby outperforming AFP. Importantly, sAxl remains normal in most common CLDs, liver adenomas and CCA. PMID:28526812

New reporting procedures based on long-term method detection levels and some considerations for interpretations of water-quality data provided by the U.S. Geological Survey National Water Quality Laboratory

USGS Publications Warehouse

Childress, Carolyn J. Oblinger; Foreman, William T.; Connor, Brooke F.; Maloney, Thomas J.

1999-01-01

This report describes the U.S. Geological Survey National Water Quality Laboratory?s approach for determining long-term method detection levels and establishing reporting levels, details relevant new reporting conventions, and provides preliminary guidance on interpreting data reported with the new conventions. At the long-term method detection level concentration, the risk of a false positive detection (analyte reported present at the long-term method detection level when not in sample) is no more than 1 percent. However, at the long-term method detection level, the risk of a false negative occurrence (analyte reported not present when present at the long-term method detection level concentration) is up to 50 percent. Because this false negative rate is too high for use as a default 'less than' reporting level, a more reliable laboratory reporting level is set at twice the determined long-term method detection level. For all methods, concentrations measured between the laboratory reporting level and the long-term method detection level will be reported as estimated concentrations. Non-detections will be censored to the laboratory reporting level. Adoption of the new reporting conventions requires a full understanding of how low-concentration data can be used and interpreted and places responsibility for using and presenting final data with the user rather than with the laboratory. Users must consider that (1) new laboratory reporting levels may differ from previously established minimum reporting levels, (2) long-term method detection levels and laboratory reporting levels may change over time, and (3) estimated concentrations are less certain than concentrations reported above the laboratory reporting level. The availability of uncensored but qualified low-concentration data for interpretation and statistical analysis is a substantial benefit to the user. A decision to censor data after they are reported from the laboratory may still be made by the user, if merited, on the basis of the intended use of the data.

Highly sensitive and specific on-site detection of serum cocaine by a low cost aptasensor.

PubMed

Oueslati, Rania; Cheng, Cheng; Wu, Jayne; Chen, Jiangang

2018-06-15

Cocaine is one of the most used illegal recreational drugs. Developing an on-site test for cocaine use detection has been a focus of research effort, since it is essential to the control and legal action against drug abuse. Currently most of cocaine detection methods are time-consuming and require special or expensive equipment, and the detection often suffers from high cross-reactivity with cocaine metabolites and relative low sensitivity with the best limit of detection reported at sub nanomolar (nM) level. In this work, an aptasensor has been developed using capacitive monitoring of sensor surface incorporating alternating current electrokinetics effects to speed up molecular transport and minimize matrix effects. The aptasensor is rapid, low cost, highly sensitive and specific as well as simple-to-use for the detection of cocaine from serum. The assay has a sample-to-result time of 30 s, a limit of detection of 7.8 fM, and a linear response for cocaine ranging from 14.5fM to 14.5pM in standard buffer, which are great improvements from other reported cocaine sensors. Special buffer is used for serum cocaine detection, and a limit of detection of 13.4 fM is experimentally demonstrated for cocaine spiked in human serum (equivalent to 1.34pM cocaine in neat serum). The specificity of the biosensor is also demonstrated with structurally similar chemicals, ecgonine ethyl ester and methylecgonidine. This biosensor shows high promise in detection of low levels of cocaine from complex matrices. Copyright © 2018 Elsevier B.V. All rights reserved.

SnO2 quantum dots with rapid butane detection at lower ppm-level

NASA Astrophysics Data System (ADS)

Cai, Pan; Dong, Chengjun; Jiang, Ming; Shen, Yuanyuan; Tao, You; Wang, Yude

2018-04-01

SnO2 quantum dots (QDs) were successfully synthesized by a facile approach employing benzyl alcohol and ammonium hydroxide at lower temperature of 130 °C. It is revealed that the SnO2 QDs is about 3 nm in size to form clusters. The gas sensor based on SnO2 QDs shows a high potential for detecting low-ppm-level butane at 400 °C, exhibiting a high sensitivity, short response and rapid recovery time, and effective selectivity. The sensing mechanism is understood in terms of adsorbed oxygen species. Significantly, the excellent sensing performance is attributed to the smaller size of SnO2 and larger surface area (204.85 m2/g).

Coherent structures in the Es layer and neutral middle atmosphere

NASA Astrophysics Data System (ADS)

Mošna, Zbyšek; Knížová, Petra Koucká; Potužníková, Kateřina

2015-12-01

The present paper shows results from the summer campaign performed during geomagnetically quiet period from June 1 to August 31, 2009. Within time-series of stratospheric and mesospheric temperatures at pressure levels 10-0.1 hPa, mesospheric winds measured in Collm, Germany, and the sporadic E-layer parameters foEs and hEs measured at the Pruhonice station we detected specific coherent wave-bursts in planetary wave domain. Permanent wave-like activity is observed in all analyzed data sets. However, the number of wave-like structures persistent in large range of height from the stratosphere to lower ionosphere is limited. The only coherent modes that are detected on consequent levels of the atmosphere are those corresponding to eigenmodes of planetary waves.

Acoustically detectable cellular-level lung injury induced by fluid mechanical stresses in microfluidic airway systems.

PubMed

Huh, Dongeun; Fujioka, Hideki; Tung, Yi-Chung; Futai, Nobuyuki; Paine, Robert; Grotberg, James B; Takayama, Shuichi

2007-11-27

We describe a microfabricated airway system integrated with computerized air-liquid two-phase microfluidics that enables on-chip engineering of human airway epithelia and precise reproduction of physiologic or pathologic liquid plug flows found in the respiratory system. Using this device, we demonstrate cellular-level lung injury under flow conditions that cause symptoms characteristic of a wide range of pulmonary diseases. Specifically, propagation and rupture of liquid plugs that simulate surfactant-deficient reopening of closed airways lead to significant injury of small airway epithelial cells by generating deleterious fluid mechanical stresses. We also show that the explosive pressure waves produced by plug rupture enable detection of the mechanical cellular injury as crackling sounds.

Conferring virus resistance in tomato by independent RNA silencing of three tomato homologs of Arabidopsis TOM1.

PubMed

Ali, Md Emran; Ishii, Yuko; Taniguchi, Jyun-Ichi; Waliullah, Sumyya; Kobayashi, Kappei; Yaeno, Takashi; Yamaoka, Naoto; Nishiguchi, Masamichi

2018-05-01

The TOM1/TOM3 genes from Arabidopsis are involved in the replication of tobamoviruses. Tomato homologs of these genes, LeTH1, LeTH2 and LeTH3, are known. In this study, we examined transgenic tomato lines where inverted repeats of either LeTH1, LeTH2 or LeTH3 were introduced by Agrobacterium. Endogenous mRNA expression for each gene was detected in non-transgenic control plants, whereas a very low level of each of the three genes was found in the corresponding line. Small interfering RNA was detected in the transgenic lines. Each silenced line showed similar levels of tobamovirus resistance, indicating that each gene is similarly involved in virus replication.

Sex steroid imbalances in the muricid Stramonita haemastoma from TBT contaminated sites.

PubMed

Rossato, M; Castro, I B; Paganini, C L; Colares, E P; Fillmann, G; Pinho, G L L

2016-04-01

Imposex incidence, organotin tissue levels, and sex steroid (free and esterified testosterone and estradiol) levels were assessed in Stramonita haemastoma from Babitonga Bay (Santa Catarina State, Southern Brazil). The imposex levels showed a reduction when compared to a previous evaluation performed in the same area. In spite of that, the detected imposex incidence indicated the occurrence of tributyltin (TBT) inputs that were still able to produce endocrine disruption in local gastropods. In addition, a high level of organotins was observed in tissues of imposexed females. These females also showed a hormonal imbalance, especially in the total testosterone/total estradiol ratio. These findings obtained under realistic field conditions suggest that the steroid pathway could be responsible by the imposex induction after exposure to TBT. In this case, measurements of sex steroid levels can be an additional evidence for monitoring sites and impose affected gastropod populations.

Analysis Of Condensate Samples In Support Of The Antifoam Degradation Study

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

Hay, M.; Martino, C.

2016-01-12

The degradation of Antifoam 747 to form flammable decomposition products has resulted in declaration of a Potential Inadequacy in the Safety Analysis (PISA) for the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) testing with simulants showed that hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and 1-propanal are formed in the offgas from the decomposition of the antifoam. A total of ten DWPF condensate samples from Batch 735 and 736 were analyzed by SRNL for three degradation products and additional analytes. All of the samples were analyzed to determine the concentrations of HMDSO, TMS, and propanal. The results of the organicmore » analysis found concentrations for propanal and HMDSO near or below the detection limits for the analysis. The TMS concentrations ranged from below detection to 11 mg/L. The samples from Batch 736 were also analyzed for formate and oxalate anions, total organic carbon, and aluminum, iron, manganese, and silicon. Most of the samples contained low levels of formate and therefore low levels of organic carbon. These two values for each sample show reasonable agreement in most cases. Low levels of all the metals (Al, Fe, Mn, and Si) were present in most of the samples.« less

ANALYSIS OF CONDENSATE SAMPLES IN SUPPORT OF THE ANTIFOAM DEGRADATION STUDY

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

Hay, M.; Martino, C.

2016-02-29

The degradation of Antifoam 747 to form flammable decomposition products has resulted in declaration of a Potential Inadequacy in the Safety Analysis (PISA) for the Defense Waste Processing Facility (DWPF). Savannah River National Laboratory (SRNL) testing with simulants showed that hexamethyldisiloxane (HMDSO), trimethylsilanol (TMS), and 1-propanal are formed in the offgas from the decomposition of the antifoam. A total of ten DWPF condensate samples from Batch 735 and 736 were analyzed by SRNL for three degradation products and additional analytes. All of the samples were analyzed to determine the concentrations of HMDSO, TMS, and propanal. The results of the organicmore » analysis found concentrations for propanal and HMDSO near or below the detection limits for the analysis. The TMS concentrations ranged from below detection to 11 mg/L. The samples from Batch 736 were also analyzed for formate and oxalate anions, total organic carbon, and aluminum, iron, manganese, and silicon. Most of the samples contained low levels of formate and therefore low levels of organic carbon. These two values for each sample show reasonable agreement in most cases. Low levels of all the metals (Al, Fe, Mn, and Si) were present in most of the samples.« less

[Cloning, expressing of exendin-4 analogue and bioactivity analysis in vivo].

PubMed

Li, Taiming; Gu, Chunjiao; Ge, Xiaoyu; Li, Zhezhe; Wang, Dan; Ma, Yanhong; Liu, Tao; Zhang, Meiyou; Li, Li; Liu, Jingjing

2012-07-01

To construct, express and purify Exendin-4 analogue and detect its biological activity in vivo. Insert gene sequence into fusion partner ofpED plasmid which is helped to purification, entitled the new recombinant plasmid 5 Exendin-4 analogue polypeptide gene and fusion partner gene was linked by acid hydrolysisgene, transformed to E. coli BL21 and the fusion protein was induced by lactose. After acid hydrolysis, the Exendin-4 analogue polypeptide separated from fusion chaperon. Anion charge chromatography were used to further purification. 6 to 8 week-old ICR mice were injected (s.c) with Exendin-4 analogue, blood glucose and plasma insulin level was detected in different period after oral glucose tolerance test. The results show that high expression of inclusion body was induced by lactose, which accounted for 40% of germ proteins, the Exendin-4 analogue was obtained with the purity of 91.8% after being purified by anion charge chromatography. Bioactivity assay showed that the level of blood glucose of mouse which treated with exendin-4 analogue was obviously decreased to normal (P < 0.01), and the level of plasma insulin was increased obviously (P < 0.01).

A Analysis of Saudi Arabian High School Students' Misconceptions about Physics Concepts.

NASA Astrophysics Data System (ADS)

Al-Rubayea, Abdullah A. M.

This study was conducted to explore Saudi high students' misconceptions in selected physics concepts. It also detected the effects of gender, grade level and location of school on Saudi high school students' misconceptions. In addition, a further analysis of students' misconceptions in each question was investigated and a correlation between students' responses, confidence in answers and sensibleness was conducted. There was an investigation of sources of students' answers in this study. Finally, this study included an analysis of students' selection of reasons only in the instrument. The instrument used to detect the students' misconceptions was a modified form of the Misconception Identification in Science Questionnaire (MISQ). This instrument was developed by Franklin (1992) to detected students' misconceptions in selected physics concepts. This test is a two-tier multiple choice test that examines four areas of physics: Force and motion, heat and temperature, light and color and electricity and magnetism. This study included a sample of 1080 Saudi high school students who were randomly selected from six Saudi educational districts. This study also included both genders, the three grade levels of Saudi high schools, six different educational districts, and a city and a town in each educational district. The sample was equally divided between genders, grade levels, and educational districts. The result of this study revealed that Saudi Arabian high school students hold numerous misconceptions about selected physics concepts. It also showed that tenth grade students were significantly different than the other grades. The result also showed that different misconceptions are held by the students for each concept in the MISQ. A positive correlation between students' responses, confidence in answers and sensibleness in many questions was shown. In addition, it showed that guessing was the most dominant source of misconceptions. The result revealed that gender and grade level had an affect on students' choice of decision on the MISQ items. A positive change in the means of gender and grade levels in the multiple choice test and gender differences in selection of reason may be associated with specific concepts. No significant difference in frequencies of the reasons chosen by the student to justify their answers were found in most of the items (10 items).

Differential expression of the eight genes of the petunia ribulose bisphosphate carboxylase small subunit multi-gene family

PubMed Central

Dean, Caroline; Elzen, Peter van den; Tamaki, Stanley; Dunsmuir, Pamela; Bedbrook, John

1985-01-01

Of the eight nuclear genes in the plant multi-gene family which encodes the small subunit (rbcS) of Petunia (Mitchell) ribulose bisphosphate carboxylase, one rbcS gene accounts for 47% of the total rbcS gene expression in petunia leaf tissue. Expression of each of five other rbcS genes is detected at levels between 2 and 23% of the total rbcS expression in leaf tissue, while expression of the remaining two rbcS genes is not detected. There is considerable variation (500-fold) in the levels of total rbcS mRNA in six organs of petunia (leaves, sepals, petals, stems, roots and stigmas/anthers). One gene, SSU301, showed the highest levels of steady-state mRNA in each of the organs examined. We discuss the differences in the steady-state mRNA levels of the individual rbcS genes in relation to their gene structure, nucleotide sequence and genomic linkage. ImagesFig. 2.Fig. 3. PMID:16453647

Recombination within the nonstructural genes of the parvovirus minute virus of mice (MVM) generates functional levels of wild-type NS1, which can be detected in the absence of selective pressure following transfection of nonreplicating plasmids.

PubMed

Pearson, J L; Pintel, D J

2000-03-30

Recombination within the coding region of the nonstructural genes of minute virus of mice (MVM), which generates functional levels of wild-type NS1, was observed in the absence of selective pressure following cotransfection of nonreplicating plasmids. P38 activity was used as a measure of recombinant NS1 production, which, together with direct detection of recombinant-generated products by RT-PCR, allowed an estimation of recombination efficiency. In addition, we show that very low levels of wild-type NS1 were able to significantly transactivate P38. Given that recombination following cotransfection can generate NS1 at these levels, our observations have implications for the study of parvoviral genetics, the construction of recombinant parvoviral vectors for gene therapy applications, and perhaps other systems using cotransfection of plasmids that share homologous sequences. Copyright 2000 Academic Press.

Verification of spectrophotometric method for nitrate analysis in water samples

NASA Astrophysics Data System (ADS)

Kurniawati, Puji; Gusrianti, Reny; Dwisiwi, Bledug Bernanti; Purbaningtias, Tri Esti; Wiyantoko, Bayu

2017-12-01

The aim of this research was to verify the spectrophotometric method to analyze nitrate in water samples using APHA 2012 Section 4500 NO3-B method. The verification parameters used were: linearity, method detection limit, level of quantitation, level of linearity, accuracy and precision. Linearity was obtained by using 0 to 50 mg/L nitrate standard solution and the correlation coefficient of standard calibration linear regression equation was 0.9981. The method detection limit (MDL) was defined as 0,1294 mg/L and limit of quantitation (LOQ) was 0,4117 mg/L. The result of a level of linearity (LOL) was 50 mg/L and nitrate concentration 10 to 50 mg/L was linear with a level of confidence was 99%. The accuracy was determined through recovery value was 109.1907%. The precision value was observed using % relative standard deviation (%RSD) from repeatability and its result was 1.0886%. The tested performance criteria showed that the methodology was verified under the laboratory conditions.

Correlation between CD64 and PCT levels in cerebrospinal fluid and degree of hearing impairment sequelae in neonates with purulent meningitis.

PubMed

Liu, Cui; Zhao, Dongchi

2017-12-01

This study investigated the possible correlation between the degree of hearing impairment caused by neonatal purulent meningitis and the levels of CD64 and PCT in cerebrospinal fluid of patients, and assessed the prognostic value of such levels. We recorded data from 156 cases of neonatal purulent meningitis retrospectively. All the patients received brainstem response audiometry, and cerebrospinal fluid samples were collected within the first day after admission through lumbar puncture. Flow cytometry was used to detect CD64 levels and enzyme-linked fluorescent assay was used to detect PCT levels. The children with hearing impairment were followed up for 1 year and brainstem response audiometry was performed again in them. We found that 43.59% of the children showed different degrees of hearing impairment, and 55% of them did not fully recover. The levels of PCT and CD64 in cerebrospinal fluid of children with hearing impairment were significantly higher than those of children with normal hearing (P<0.01). The levels of PCT and CD64 in mild, moderate and severe hearing impaired children increased gradually with higher degrees of impairment, and the differences between groups were significant (P<0.01). During the follow-up, it was found that the levels of PCT and CD64 in children correlated well with the degree of hearing recovery, and the differences between groups were significant (P<0.01). In our study, approximately 1/4 children with purulent meningitis showed long-term hearing impairment. Based on our analyses, the levels of CD64 and PCT in cerebrospinal fluid can be used to predict the degree and long-term prognosis of hearing impairment caused by purulent meningitis in children.

Follow-up of blood glucose distribution characteristics in a health examination population in Chengdu from 2010 to 2016.

PubMed

Wang, Yuting; Xu, Wangdong; Zhang, Qiongying; Bao, Ting; Yang, Hanwei; Huang, Wenxia; Tang, Huairong

2018-02-01

The worldwide prevalence and incidence of diabetes and obesity are increasing in pandemic proportions. Thus, regular health examination is an important way for early detection of diabetes and glucose intolerance. The present study aims to detect the blood glucose distribution characteristics of the participants in the Health Examination Center at West China Hospital, Sichuan University from 2010 to 2016.A prospective cohort included 9168 Chinese participants, aged 18 years or more, who had available information on fasting blood glucose concentrations at the start of the study (2010). Examination surveys were conducted every year from 2010 to 2016. Cases having serum level of fasting blood glucose between 2.2 and 6.1 mmol/L were considered as normality, while serum level of fasting blood glucose < 2.2 or higher than 6.2 mmol/L were considered as abnormality.The percentage of participants having normal level of glucose was gradually reduced both in males and females from 2010 to 2016, by which the percentage of males having normal level of glucose was significantly lower than that in females. Moreover, the mean level of glucose was significantly increased from 2010 to 2016 both in males and females overall, and the mean level of glucose was higher in males compared with that in females every year. Furthermore, we showed that the level of glucose was gradually increased year by year in each age group, and the level of glucose was higher in aged cases compared with the young population.The study population in the current study showed higher levels of glucose with ages increasing, and males indicated higher expression of glucose than that in females. Some preventive action may be adopted early and more attention can be paid to this health-examination population.

Real Time Monitoring System of Pollution Waste on Musi River Using Support Vector Machine (SVM) Method

NASA Astrophysics Data System (ADS)

Fachrurrozi, Muhammad; Saparudin; Erwin

2017-04-01

Real-time Monitoring and early detection system which measures the quality standard of waste in Musi River, Palembang, Indonesia is a system for determining air and water pollution level. This system was designed in order to create an integrated monitoring system and provide real time information that can be read. It is designed to measure acidity and water turbidity polluted by industrial waste, as well as to show and provide conditional data integrated in one system. This system consists of inputting and processing the data, and giving output based on processed data. Turbidity, substances, and pH sensor is used as a detector that produce analog electrical direct current voltage (DC). Early detection system works by determining the value of the ammonia threshold, acidity, and turbidity level of water in Musi River. The results is then presented based on the level group pollution by the Support Vector Machine classification method.

Cognitive workload modulation through degraded visual stimuli: a single-trial EEG study

NASA Astrophysics Data System (ADS)

Yu, K.; Prasad, I.; Mir, H.; Thakor, N.; Al-Nashash, H.

2015-08-01

Objective. Our experiments explored the effect of visual stimuli degradation on cognitive workload. Approach. We investigated the subjective assessment, event-related potentials (ERPs) as well as electroencephalogram (EEG) as measures of cognitive workload. Main results. These experiments confirm that degradation of visual stimuli increases cognitive workload as assessed by subjective NASA task load index and confirmed by the observed P300 amplitude attenuation. Furthermore, the single-trial multi-level classification using features extracted from ERPs and EEG is found to be promising. Specifically, the adopted single-trial oscillatory EEG/ERP detection method achieved an average accuracy of 85% for discriminating 4 workload levels. Additionally, we found from the spatial patterns obtained from EEG signals that the frontal parts carry information that can be used for differentiating workload levels. Significance. Our results show that visual stimuli can modulate cognitive workload, and the modulation can be measured by the single trial EEG/ERP detection method.

Crossing the other side of the algorithm: a challenging case of adrenal Cushing's syndrome.

PubMed

Antonio, Imelda Digna Soberano; Sandoval, Mark Anthony Santiago; Lantion-Ang, Frances Lina

2011-12-01

The diagnosis of endogenous Cushing's syndrome and its aetiology involved documenting the hypercotisolism and then determining whether that hypercortisolism is adrenocorticotropic hormone-dependent (ACTH-dependent) or not. Hence, following the algorithm, an undetected ACTH level points to an adrenal Cushing's while a detectable or elevated ACTH level points to either a pituitary or ectopic Cushing's syndrome. The authors present a case of florid adrenal Cushing's syndrome initially presenting with a normal ACTH level, which led to the investigation for an ACTH-secreting tumour. Adding to the confusion, a MRI done showed an intrasellar focus. Knowledge of how ACTH-dependent (versus ACTH-independent) Cushing's syndrome manifests clinically, supported by results of repeat laboratory tests, led to the true diagnosis. This case illustrates that a detectable ACTH does not rule out an adrenal Cushing's syndrome nor does a positive pituitary imaging confirm Cushing's disease.

Evaluation of the capabilities of satellite imagery for monitoring regional air pollution episodes

NASA Technical Reports Server (NTRS)

Barnes, J. C.; Bowley, C. J.; Burke, H. H. K.

1979-01-01

A comparative analysis of satellite visible channel imagery and ground based aerosol measurements is carried out for three cases representing a significant pollution episodes based on low surface visibility and high sulfate levels. The feasibility of detecting pollution episodes from space is also investigated using a simulation model. The model results are compared to quantitative information derived from digitized satellite data. The results show that when levels are or = 30 micrograms/cu, a haze pattern that correlates closely with the area of reported low surface visibilities and high micrograms sulfate levels can be detected in satellite visible channel imagery. The model simulation demonstrates the potential of the satellite to monitor the magnitude and areal extent of pollution episodes. Quantitative information on total aerosol amount derived from the satellite digitized data using the atmospheric radiative transfer model agrees well with the results obtained from the ground based measurements.

Responses of chub (Leuciscus cephalus) populations to chemical stress, assessed by genetic markers, DNA damage and cytochrome P4501A induction.

PubMed

Larno, V; Laroche, J; Launey, S; Flammarion, P; Devaux, A

2001-06-01

Indicators of effects at the population level (genetic variation using allozymes) and early indicators of pollution (EROD activity and DNA strand break formation) were analysed in chub (Leuciscus cephalus) living in weakly and heavily contaminated stations of the Rhône River watershed. The genetic erosion was mainly detected in a fish population living in a contaminated small river system, through modifications in allelic and genotypic frequencies for PGM-2 locus and could be linked to a genetic bottleneck and to the reduced gene flow from upstream unable to maintain or restore the genetic diversity. In a contaminated large river system, the genetic diversity for PGM-2 and other loci was maintained and was probably the consequence of a high gene flow from upstream, linked to a sustained drift of larvae and juveniles in the system. A convergent increase of the frequency of the 90 allele at PGM-2 was observed in two contaminated stations compared with the reference station, this trend being confirmed on a more extensive geographic scale over the Rhône River basin. A high level of EROD activity was detected in both contaminated sites but only the fish in the large river system showed a significant DNA damage level compared to the reference population. The low DNA damage level and high hepato-somatic ratio characterized the impacted population of the small river system and could be associated to a chronic high-level exposure of fish to pollutants which selected individuals exhibiting a high level of DNA damage repair. In the two contaminated systems, some genotypes at the PGM-2 and EST-2 loci showed a low level of DNA damage and/or a high EROD activity and may be considered as being tolerant to pollutants. A higher tolerance of the most heterozygous fish was also detected in the contaminated large system and confirmed that a high level of heterozygosity may be necessary for survival in such a system.

Pitfalls in the detection of cholesterol in Huntington’s disease models

PubMed Central

Marullo, Manuela; Valenza, Marta; Leoni, Valerio; Caccia, Claudio; Scarlatti, Chiara; De Mario, Agnese; Zuccato, Chiara; Di Donato, Stefano; Carafoli, Ernesto; Cattaneo, Elena

2012-01-01

Background Abnormalities in brain cholesterol homeostasis have been reported in Huntington’s disease (HD), an adult-onset neurodegenerative disorder caused by an expansion in the number of CAG repeats in the huntingtin (HTT) gene. However, the results have been contradictory with respect to whether cholesterol levels increase or decrease in HD models. Biochemical and mass spectrometry methods show reduced levels of cholesterol precursors and cholesterol in HD cells and in the brains of several HD animal models. Abnormal brain cholesterol homeostasis was also inferred from studies in HD patients. In contrast, colorimetric and enzymatic methods indicate cholesterol accumulation in HD cells and tissues. Here we used several methods to investigate cholesterol levels in cultured cells in the presence or absence of mutant HTT protein. Results Colorimetric and enzymatic methods with low sensitivity gave variable results, whereas results from a sensitive analytical method, gas chromatography-mass spectrometry, were more reliable. Sample preparation, high cell density and cell clonality also influenced the detection of intracellular cholesterol. Conclusions Detection of cholesterol in HD samples by colorimetric and enzymatic assays should be supplemented by detection using more sensitive analytical methods. Care must be taken to prepare the sample appropriately. By evaluating lathosterol levels using isotopic dilution mass spectrometry, we confirmed reduced cholesterol biosynthesis in knock-in cells expressing the polyQ mutation in a constitutive or inducible manner. *Correspondence should be addressed to Elena Cattaneo: elena.cattaneo@unimi.it PMID:23145355

Polycyclic aromatic hydrocarbons in surface sediment of typical estuaries and the spatial distribution in Haihe river basin.

PubMed

Liu, Jing L; Zhang, Jing; Liu, Feng; Zhang, Lu L

2014-05-01

Polycyclic aromatic hydrocarbons (PAHs) with carcinogenic and mutagenic characteristics have been detected in many estuaries and bays around the world. To detect the contaminated level in typical estuaries in Haihe river basin, China, a comprehensive survey of 16 PAHs in surface sediment has been conducted and an ecological risk assessment has been taken. It showed that Haihe river estuary had the highest concentration, ranging from 92.91 to 15886.00 ng g(-1). And Luan river estuary has the lowest polluted level, ranging from 39.55 to 328.10 ng g(-1). PAHs in sediment were dominated by low and mid molecular weight PAHs in all the sampling sites. Most of the sampling sites in all sampling seasons indicated a rarely happened ecological risk of ΣPAHs, while the S6 in Haihe river estuary was in an occasionally anticipated risk. To illustrate the spatial distribution pattern of PAHs in surface sediment in Haihe river basin, the results were compared with previous research of the research team. Based on data of the comparison, it had been revealed that Haihe river had the most serious PAHs pollution, with an average concentration of 5884.86 ng g(-1), and showed the highest contamination level in all four ecological units. The ΣPAHs concentration showed in a rank of reservoir > estuary > rural area > city.

Reduction of factor XII in antiphospholipid antibody-positive patients with thrombotic events in the rheumatology clinic.

PubMed

Takeishi, M; Mimori, A; Nakajima, K; Mimura, T; Suzuki, T

2003-02-01

Although rheumatological diagnosis often includes an assessment of antiphospholipid (aPL) antibodies, the significance of other prothrombotic factors has not been established in thrombotic patients who are not afflicted with either arteriosclerosis or vasculitis syndrome. We have observed both the presence of antiphospholipid antibodies and a reduction of factor XII in such patients. Our results identified both lupus anticoagulant-positive (50%) and anticardiolipin antibody-positive (58%) patients. In addition, 83% of patients showed factor XII antigen level reduction. Furthermore, 70% of aPL-positive thrombotic patients showed factor XII antigen level reduction. Only two cases had antiphospholipid antibody alone, and 4/12 showed just factor XII antigen reduction. Recently, it has been reported that the presence of antiphospholipid antibodies induces factor XII reduction, and that anti-factor XII autoantibody can be detected in thrombotic patients. However, our results indicate that there are smaller factor XII reductions in non-thrombotic controls who are positive for antiphospholipid antibodies. Furthermore, anti-factor XII autoantibody was not detected in patients with decreased factor XII levels. Kindred research suggested that in two patients there was a genetic component to factor XII reduction. We concluded that the presence of both antiphospholipid antibodies and reduced serum factor XII was observed in most thrombotic patients from our rheumatology clinic. It is therefore possible to consider that the coexistence of these prothrombotic factors can contribute to the onset of thrombosis.

Molecular Identification of Bacteria from Aseptically Loose Implants

PubMed Central

Kobayashi, Naomi; Procop, Gary W.; Krebs, Viktor; Kobayashi, Hideo

2008-01-01

Polymerase chain reaction (PCR) assays have been used to detect bacteria adherent to failed orthopaedic implants, but some PCR assays have had problems with probable false-positive results. We used a combination of a Staphylococcus species-specific PCR and a universal PCR followed by DNA sequencing to identify bacteria on implants retrieved from 52 patients (92 implants) at revision arthroplasty. We addressed two questions in this study: (1) Is this method able to show the existence of bacterial DNA on presumed aseptic loosed implants?; and (2) What proportion of presumed aseptic or culture-negative implants was positive for bacterial DNA by PCR? Fourteen implants (15%) were believed infected, whereas 74 implants (85%) were believed aseptic. Each implant was sonicated and the resulting solution was submitted for dual real-time PCR assay and culture. All implants believed aseptically loose were culture-negative, but nine of the 74 (12%) had bacterial DNA by PCR; two (2.7%) were PCR-positive and also showed histologic findings suggestive of infection. Uniquely developed PCR and bacterial sequencing assays showed bacterial DNA on 12% of implants removed for presumed aseptic loosening. Additional studies are needed to determine the clinical importance of bacterial DNA detected by PCR but not by conventional culture. Level of Evidence: Level III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence. PMID:18438724

Ultrasensitive optical detection of trinitrotoluene by ethylenediamine-capped gold nanoparticles.

PubMed

Lin, Dongyue; Liu, Honglin; Qian, Kai; Zhou, Xia; Yang, Liangbao; Liu, Jinhuai

2012-09-26

This study found that 1,2-ethylenediamine (EDA) as a primary amine could be modified onto the surface of citrate-stabilized gold nanoparticles (Au NPs), and the EDA-capped Au NPs were successfully used as an ultrasensitive optical probe for TNT detection. The strong donor-acceptor (D-A) interactions between EDA and trinitrotoluene (TNT) at the Au NP/solution interface induced significant aggregation of the EDA-capped Au NPs, and enabled to easily realize the direct colorimetric detection of ultratrace TNT. The results showed that such a color change was readily seen by the naked eye, and the colorimetric detection could be down to 400 pM level of TNT with excellent discrimination against other nitro compounds. UV-vis absorption spectroscopy was used to examine the TNT-induced changes in local surface plasmon resonance (LSPR) of EDA-capped Au NPs, and a new LSPR band at ca. 630 nm arose along with the addition of TNT, which produced a detection limit of TNT down to ca. 40 pM. Furthermore, dynamic light scattering measurements evidenced the ultratrace TNT-induced small changes in the size of the EDA-capped Au NPs, and realized the quick and accurate detection of TNT in 0.4 pM level. These results demonstrated the ultrahigh sensitivity of this optical probe for TNT detection. Moreover, this optical probe is sample, stable, low-cost, and these excellent properties make it quite promising for infield and rapid detection of TNT. Copyright © 2012 Elsevier B.V. All rights reserved.

Sea level hazards: Altimetric monitoring of tsunamis and sea level rise

NASA Astrophysics Data System (ADS)

Hamlington, Benjamin Dillon

Whether on the short timescale of an impending tsunami or the much longer timescale of climate change-driven sea level rise, the threat stemming from rising and inundating ocean waters is a great concern to coastal populations. Timely and accurate observations of potentially dangerous changes in sea level are vital in determining the precautionary steps that need to be taken in order to protect coastal communities. While instruments from the past have provided in situ measurements of sea level at specific locations across the globe, satellites can be used to provide improved spatial and temporal sampling of the ocean in addition to producing more accurate measurements. Since 1993, satellite altimetry has provided accurate measurements of sea surface height (SSH) with near-global coverage. Not only have these measurements led to the first definitive estimates of global mean sea level rise, satellite altimetry observations have also been used to detect tsunami waves in the open ocean where wave amplitudes are relatively small, a vital step in providing early warning to those potentially affected by the impending tsunami. The use of satellite altimetry to monitor two specific sea level hazards is examined in this thesis. The first section will focus on the detection of tsunamis in the open ocean for the purpose of providing early warning to coastal inhabitants. The second section will focus on estimating secular trends using satellite altimetry data with the hope of improving our understanding of future sea level change. Results presented here will show the utility of satellite altimetry for sea level monitoring and will lay the foundation for further advancement in the detection of the two sea level hazards considered.

Statistical process control and verifying positional accuracy of a cobra motion couch using step-wedge quality assurance tool.

PubMed

Binny, Diana; Lancaster, Craig M; Trapp, Jamie V; Crowe, Scott B

2017-09-01

This study utilizes process control techniques to identify action limits for TomoTherapy couch positioning quality assurance tests. A test was introduced to monitor accuracy of the applied couch offset detection in the TomoTherapy Hi-Art treatment system using the TQA "Step-Wedge Helical" module and MVCT detector. Individual X-charts, process capability (cp), probability (P), and acceptability (cpk) indices were used to monitor a 4-year couch IEC offset data to detect systematic and random errors in the couch positional accuracy for different action levels. Process capability tests were also performed on the retrospective data to define tolerances based on user-specified levels. A second study was carried out whereby physical couch offsets were applied using the TQA module and the MVCT detector was used to detect the observed variations. Random and systematic variations were observed for the SPC-based upper and lower control limits, and investigations were carried out to maintain the ongoing stability of the process for a 4-year and a three-monthly period. Local trend analysis showed mean variations up to ±0.5 mm in the three-monthly analysis period for all IEC offset measurements. Variations were also observed in the detected versus applied offsets using the MVCT detector in the second study largely in the vertical direction, and actions were taken to remediate this error. Based on the results, it was recommended that imaging shifts in each coordinate direction be only applied after assessing the machine for applied versus detected test results using the step helical module. User-specified tolerance levels of at least ±2 mm were recommended for a test frequency of once every 3 months to improve couch positional accuracy. SPC enables detection of systematic variations prior to reaching machine tolerance levels. Couch encoding system recalibrations reduced variations to user-specified levels and a monitoring period of 3 months using SPC facilitated in detecting systematic and random variations. SPC analysis for couch positional accuracy enabled greater control in the identification of errors, thereby increasing confidence levels in daily treatment setups. © 2017 Royal Brisbane and Women's Hospital, Metro North Hospital and Health Service. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

Specificity of L1 Peptides versus Virus-Like Particles for Detection of Human Papillomavirus-Positive Cervical Lesions in Females Attending Engativa Hospital, Bogota, Colombia▿

PubMed Central

Urquiza, Mauricio; Sánchez, Ricardo; Amaya, Jairo; León, Sandra; Acosta, Jenny; Patarroyo, Manuel A.; Camargo, Milena; Patarroyo, Manuel E.

2008-01-01

A serological test for the detection of human papillomavirus (HPV) infection in females at risk of developing cervical cancer could be based on conserved L1 peptides with low levels of antigenicity specifically recognized by antibodies from patients with cervical lesions infected with high-risk HPV (HR-HPV) types. The aim was to assess the ability of L1 peptides 18283, 18294, and 18301 compared with the ability of virus-like particles (VLPs) to identify these infections in females. A total of 391 HPV-infected female volunteers were interviewed, and peripheral blood and cervical cells were obtained for detection of anti-HPV antibodies and HPV DNA; all of the patients had a Pap smear test; 287 patients were referred for colposcopy or biopsy, according to gynecological criteria. The level of agreement, as determined by the use of the Lin coefficient (rho value), showed that 75 to 83% of females with HR-HPV DNA-positive cervical lesions had antibodies that recognized VLPs and peptide 18283, 18294, or 18301, while 15 to 23% of the HPV DNA-negative females with a normal cytology had antibodies that recognized these three peptides and 45% had antibodies that recognized VLPs. The rate of agreement between peptides and VLPs for antibody detection was higher for patients with HPV DNA-positive cervical lesions. Peptides 18283, 18294, and 18301 showed similar sensitivities for the detection of HR-HPV DNA-positive cervical lesions and were more specific than VLPs. Peptide 18301 might be detecting protective antibodies in HPV DNA-negative females with atypical squamous cells of undetermined significance. These peptides could be useful for the design of a serology test for the detection of HR-HPV infection in females with cervical lesions and at risk of cervical cancer. PMID:18799706

Identification of Differentially Methylated Sites with Weak Methylation Effects

PubMed Central

Tran, Hong; Zhu, Hongxiao; Wu, Xiaowei; Kim, Gunjune; Clarke, Christopher R.; Larose, Hailey; Haak, David C.; Westwood, James H.; Zhang, Liqing

2018-01-01

Deoxyribonucleic acid (DNA) methylation is an epigenetic alteration crucial for regulating stress responses. Identifying large-scale DNA methylation at single nucleotide resolution is made possible by whole genome bisulfite sequencing. An essential task following the generation of bisulfite sequencing data is to detect differentially methylated cytosines (DMCs) among treatments. Most statistical methods for DMC detection do not consider the dependency of methylation patterns across the genome, thus possibly inflating type I error. Furthermore, small sample sizes and weak methylation effects among different phenotype categories make it difficult for these statistical methods to accurately detect DMCs. To address these issues, the wavelet-based functional mixed model (WFMM) was introduced to detect DMCs. To further examine the performance of WFMM in detecting weak differential methylation events, we used both simulated and empirical data and compare WFMM performance to a popular DMC detection tool methylKit. Analyses of simulated data that replicated the effects of the herbicide glyphosate on DNA methylation in Arabidopsis thaliana show that WFMM results in higher sensitivity and specificity in detecting DMCs compared to methylKit, especially when the methylation differences among phenotype groups are small. Moreover, the performance of WFMM is robust with respect to small sample sizes, making it particularly attractive considering the current high costs of bisulfite sequencing. Analysis of empirical Arabidopsis thaliana data under varying glyphosate dosages, and the analysis of monozygotic (MZ) twins who have different pain sensitivities—both datasets have weak methylation effects of <1%—show that WFMM can identify more relevant DMCs related to the phenotype of interest than methylKit. Differentially methylated regions (DMRs) are genomic regions with different DNA methylation status across biological samples. DMRs and DMCs are essentially the same concepts, with the only difference being how methylation information across the genome is summarized. If methylation levels are determined by grouping neighboring cytosine sites, then they are DMRs; if methylation levels are calculated based on single cytosines, they are DMCs. PMID:29419727

AMPK and SIRT1 activation contribute to inhibition of neuroinflammation by thymoquinone in BV2 microglia.

PubMed

Velagapudi, Ravikanth; El-Bakoush, Abdelmeneim; Lepiarz, Izabela; Ogunrinade, Folashade; Olajide, Olumayokun A

2017-11-01

Thymoquinone is a known inhibitor of neuroinflammation. However, the mechanism(s) involved in its action remain largely unknown. In this study, we investigated the roles of cellular reactive oxygen species (ROS), 5' AMP-activated protein kinase (AMPK) and sirtuin 1 (SIRT1) in the anti-neuroinflammatory activity of thymoquinone. We investigated effects of the compound on ROS generation in LPS-activated microglia using the fluorescent 2',7'-dichlorofluorescin diacetate (DCFDA)-cellular ROS detection. Immunoblotting was used to detect protein levels of p40 phox , gp91 phox , AMPK, LKB1 and SIRT1. Additionally, ELISA and immunofluorescence were used to detect nuclear accumulation of SIRT1. NAD + /NADH assay was also performed. The roles of AMPK and SIRT1 in anti-inflammatory activity of thymoquinone were investigated using RNAi and pharmacological inhibition. Our results show that thymoquinone reduced cellular ROS generation, possibly through inhibition of p40 phox and gp91 phox protein. Treatment of BV2 microglia with thymoquinone also resulted in elevation in the levels of LKB1 and phospho-AMPK proteins. We further observed that thymoquinone reduced cytoplasmic levels and increased nuclear accumulation of SIRT1 protein and increased levels of NAD + . Results also show that the anti-inflammatory activity of thymoquinone was abolished when the expressions of AMPK and SIRT1 were suppressed by RNAi or pharmacological antagonists. Pharmacological antagonism of AMPK reversed thymoquinone-induced increase in SIRT1. Taken together, we propose that thymoquinone inhibits cellular ROS generation in LPS-activated BV2 microglia. It is also suggested that activation of both AMPK and NAD + /SIRT1 may contribute to the anti-inflammatory, but not antioxidant activity of the compound in BV2 microglia.

Validation of quantitative light-induced fluorescence-digital (QLF-D) for the detection of approximal caries in vitro.

PubMed

Ko, Hae-Youn; Kang, Si-Mook; Kim, Hee Eun; Kwon, Ho-Keun; Kim, Baek-Il

2015-05-01

Detection of approximal caries lesions can be difficult due to their anatomical position. This study aimed to assess the ability of the quantitative light-induced fluorescence-digital (QLF-D) in detecting approximal caries, and to compare the performance with those of the International Caries Detection and Assessment System II (ICDAS II) and digital radiography (DR). Extracted permanent teeth (n=100) were selected and mounted in pairs. The simulation pairs were assessed by one calibrated dentist using each detection method. After all the examinations, the teeth (n=95) were sectioned and examined histologically as gold standard. The modalities were compared in terms of sensitivity, specificity, areas under receiver operating characteristic curves (AUROC) for enamel (D1) and dentine (D3) levels. The intra-examiner reliability was assessed for all modalities. At D1 threshold, the ICDAS II presented the highest sensitivity (0.80) while the DR showed the highest specificity (0.89); however, the methods with the greatest AUC values at D1 threshold were DR and QLF-D (0.80 and 0.80 respectively). At D3 threshold, the methods with the highest sensitivity were ICDAS II and QLF-D (0.64 and 0.64 respectively) while the method with the lowest sensitivity was DR (0.50). However, with regard to the AUC values at D3 threshold, the QLF-D presented the highest value (0.76). All modalities showed to have excellent intra-examiner reliability. The newly developed QLF-D was not only able to detect proximal caries, but also showed to have comparable performance to the visual inspection and radiography in detecting proximal caries. QLF-D has the potential to be a useful detection method for proximal caries. Copyright © 2015 Elsevier Ltd. All rights reserved.

Aflatoxin M1 Concentration in Various Dairy Products: Evidence for Biologically Reduced Amount of AFM1 in Yoghurt

PubMed Central

RAHIMIRAD, Amir; MAALEKINEJAD, Hassan; OSTADI, Araz; YEGANEH, Samal; FAHIMI, Samira

2014-01-01

Abstract Background Aflatoxin M1 (AFM1), a carcinogenic substance is found in milk and dairy products. The effect of season and type of dairy products on AFMi level in northern Iran was investigated in this study. Methods Three hundred samples (each season 75 samples) including raw and pasteurized milk, yoghurt, cheese, and cream samples were collected from three distinct milk producing farms. The samples were subjected to chemical and solid phase extractions and were analyzed by using HPLC technique. Recovery percentages, limit of detection and limit of quantification values were determined. Results Seventy percent and 98% were the minimum and maximum recoveries for cheese and raw milk, respectively and 0.021 and 0.063 ppb were the limit of detection and limit of quantification values for AFM1. We found that in autumn and winter the highest level (0.121 ppb) of AFM1 in cheese and cream samples and failed to detect any AFM1 in spring samples. Interestingly, our data showed that the yoghurt samples had the lowest level of AFM1 in all seasons. Conclusion There are significant differences between the AFM1 levels in dairy products in various seasons and also various types of products, suggesting spring and summer yoghurt samples as the safest products from AFM1 level point of view. PMID:25927044

Evaluation of Parallel and Fan-Beam Data Acquisition Geometries and Strategies for Myocardial SPECT Imaging

NASA Astrophysics Data System (ADS)

Qi, Yujin; Tsui, B. M. W.; Gilland, K. L.; Frey, E. C.; Gullberg, G. T.

2004-06-01

This study evaluates myocardial SPECT images obtained from parallel-hole (PH) and fan-beam (FB) collimator geometries using both circular-orbit (CO) and noncircular-orbit (NCO) acquisitions. A newly developed 4-D NURBS-based cardiac-torso (NCAT) phantom was used to simulate the /sup 99m/Tc-sestamibi uptakes in human torso with myocardial defects in the left ventricular (LV) wall. Two phantoms were generated to simulate patients with thick and thin body builds. Projection data including the effects of attenuation, collimator-detector response and scatter were generated using SIMSET Monte Carlo simulations. A large number of photon histories were generated such that the projection data were close to noise free. Poisson noise fluctuations were then added to simulate the count densities found in clinical data. Noise-free and noisy projection data were reconstructed using the iterative OS-EM reconstruction algorithm with attenuation compensation. The reconstructed images from noisy projection data show that the noise levels are lower for the FB as compared to the PH collimator due to increase in detected counts. The NCO acquisition method provides slightly better resolution and small improvement in defect contrast as compared to the CO acquisition method in noise-free reconstructed images. Despite lower projection counts the NCO shows the same noise level as the CO in the attenuation corrected reconstruction images. The results from the channelized Hotelling observer (CHO) study show that FB collimator is superior to PH collimator in myocardial defect detection, but the NCO shows no statistical significant difference from the CO for either PH or FB collimator. In conclusion, our results indicate that data acquisition using NCO makes a very small improvement in the resolution over CO for myocardial SPECT imaging. This small improvement does not make a significant difference on myocardial defect detection. However, an FB collimator provides better defect detection than a PH collimator with similar spatial resolution for myocardial SPECT imaging.

Assessing the impacts of canopy openness and flight parameters on detecting a sub-canopy tropical invasive plant using a small unmanned aerial system

NASA Astrophysics Data System (ADS)

Perroy, Ryan L.; Sullivan, Timo; Stephenson, Nathan

2017-03-01

Small unmanned aerial systems (sUAS) have great potential to facilitate the early detection and management of invasive plants. Here we show how very high-resolution optical imagery, collected from small consumer-grade multirotor UAS platform at altitudes of 30-120 m above ground level (agl), can be used to detect individual miconia (Miconia calvescens) plants in a highly invaded tropical rainforest environment on the island of Hawai'i. The central aim of this research was to determine how overstory vegetation cover, imagery resolution, and camera look-angle impact the aerial detection of known individual miconia plants. For our finest resolution imagery (1.37 cm ground sampling distance collected at 30 m agl), we obtained a 100% detection rate for sub-canopy plants with above-crown openness values >40% and a 69% detection rate for those with >20% openness. We were unable to detect any plants with <10% above crown openness. Detection rates progressively declined with coarser spatial resolution imagery, ending in a 0% detection rate for the 120 m agl flights (ground sampling distance of 5.31 cm). The addition of forward-looking oblique imagery improved detection rates for plants below overstory vegetation, though this effect decreased with increasing flight altitude. While dense overstory canopy cover, limited flight times, and visual line of sight regulations present formidable obstacles for detecting miconia and other invasive plant species, we show that sUAS platforms carrying optical sensors can be an effective component of an integrated management plan within challenging subcanopy forest environments.

Consensus report of the Working Group on: "Molecular and Biochemical Markers of Alzheimer's Disease". The Ronald and Nancy Reagan Research Institute of the Alzheimer's Association and the National Institute on Aging Working Group.

PubMed

1998-01-01

The ideal biomarker for Alzheimer's disease (AD) should detect a fundamental feature of neuropathology and be validated in neuropathologically-confirmed cases; it should have a sensitivity >80% for detecting AD and a specificity of >80% for distinguishing other dementias; it should be reliable, reproducible, non-invasive, simple to perform, and inexpensive. Recommended steps to establish a biomarker include confirmation by at least two independent studies conducted by qualified investigators with the results published in peer-reviewed journals. Our review of current candidate markers indicates that for suspected early-onset familial AD, it is appropriate to search for mutations in the presenilin 1, presenilin 2, and amyloid precursor protein genes. Individuals with these mutations typically have increased levels of the amyloid Abeta42 peptide in plasma and decreased levels of APPs in cerebrospinal fluid. In late-onset and sporadic AD, these measures are not useful, but detecting an apolipoprotein E e4 allele can add confidence to the clinical diagnosis. Among the other proposed molecular and biochemical markers for sporadic AD, cerebrospinal fluid assays showing low levels of Abeta42 and high levels of tau come closest to fulfilling criteria for a useful biomarker.

Organochlorine Pesticides (OCPs) in raft mussels coming from Galician rías.

PubMed

Carro, Nieves; García, Isabel; Ignacio, María; Mouteira, Ana

2017-09-01

This survey gives an overview of the range of organochlorine pesticides (OCPs) α and γ-HCH (lindane), HCB, pp´-DDE, pp´-DDD, op´-DDT, pp´-DDT, aldrin, dieldrin, endrin, isodrin and trans-nonachlor in raft mussels cultivated in several polygons of the Galician Rías (Ares-Betanzos, Muros-Noia, Arousa, Pontevedra and Vigo) during the period 1998-2014. A significant number of OCPs were detected, but the levels found were generally low, mainly in the recent samplings (2010-2014). The levels of ∑DDs (sum of DDTs and its metabolites, pp´-DDE and pp´-DDD) ranged between 0.22 ng/g dry weight (dw) in samples from the Ría of Pontevedra and 46.4 ng/g dw in mussels from the Ría of Arousa. Both aldrin and endrin were not detected or were below the analytical limits of detection. With regard to other pesticides, dieldrin is the major compound, followed by γ-HCH, isodrin, α-HCH and transnonachlor. Significant ANOVA regressions indicated variations in levels of some OCPs with the biological parameters (lipid, condition index and shell length). Univariate and multivariate analysis of OCP levels revealed no significant differences between Rías. Temporal trends showed an important decline of OCPs in the studied samples during the period 1998-2014.

Digital transillumination in caries detection versus radiographic and clinical methods: an in-vivo study

PubMed Central

Lara-Capi, Cynthia; Lingström, Peter; Lai, Gianfranco; Cocco, Fabio; Simark-Mattsson, Charlotte; Campus, Guglielmo

2017-01-01

Objectives: This article aimed to evaluate: (a) the agreement between a near-infrared light transillumination device and clinical and radiographic examinations in caries lesion detection and (b) the reliability of images captured by the transillumination device. Methods: Two calibrated examiners evaluated the caries status in premolars and molars on 52 randomly selected subjects by comparing the transillumination device with a clinical examination for the occlusal surfaces and by comparing the transillumination device with a radiographic examination (bitewing radiographs) for the approximal surfaces. Forty-eight trained dental hygienists evaluated and reevaluated 30 randomly selected images 1-month later. Results: A high concordance between transillumination method and clinical examination (kappa = 0.99) was detected for occlusal caries lesions, while for approximal surfaces, the transillumination device identified a higher number of lesions with respect to bitewing (kappa = 0.91). At the dentinal level, the two methods identified the same number of caries lesions (kappa = 1), whereas more approximal lesions were recorded using the transillumination device in the enamel (kappa = 0.24). The intraexaminer reliability was substantial/almost perfect in 59.4% of the participants. Conclusions: The transillumination method showed a high concordance compared with traditional methods (clinical examination and bitewing radiographs). Caries detection reliability using the transillumination device images showed a high intraexaminer agreement. Transillumination showed to be a reliable method and as effective as traditional methods in caries detection. PMID:28191797

Regulated expression of homeobox genes Msx-1 and Msx-2 in mouse mammary gland development suggests a role in hormone action and epithelial-stromal interactions.

PubMed

Friedmann, Y; Daniel, C W

1996-07-10

The murine homeobox genes Msx-1 and Msx-2 are related to the Drosophila msh gene and are expressed in a variety of tissues during mouse embryogenesis. We now report the developmentally regulated expression of Msx-1 and Msx-2 in the mouse mammary gland and show that their expression patterns point toward significant functional roles. Msx-1 and Msx-2 transcripts were present in glands of virgin mice and in glands of mice in early pregnancy, but transcripts decreased dramatically during late pregnancy. Low levels of Msx-1 transcripts were detected in glands from lactating animals and during the first days of involution, whereas Msx-2 expression was not detected during lactation or early involution. Expression of both genes increased gradually as involution progressed. Msx-2 but not Msx-1 expression was decreased following ovariectomy or following exposure to anti-estrogen implanted directly into the gland. Hormonal regulation of Msx-2 expression was confirmed when transcripts returned to normal levels after estrogen was administered to ovariectomized animals. In situ molecular hybridization for Msx-1 showed transcripts localized to the mammary epithelium, whereas Msx-2 expression was confined to the periductal stroma. Mammary stroma from which mammary epithelium had been removed did not transcribe detectable amounts of Msx-2, showing that expression is regulated by contiguous mammary epithelium, and indicating a role for these homeobox genes in mesenchymal-epithelial interactions during mammary development.

An exudate detection method for diagnosis risk of diabetic macular edema in retinal images using feature-based and supervised classification.

PubMed

Marin, D; Gegundez-Arias, M E; Ponte, B; Alvarez, F; Garrido, J; Ortega, C; Vasallo, M J; Bravo, J M

2018-01-10

The present paper aims at presenting the methodology and first results of a detection system of risk of diabetic macular edema (DME) in fundus images. The system is based on the detection of retinal exudates (Ex), whose presence in the image is clinically used for an early diagnosis of the disease. To do so, the system applies digital image processing algorithms to the retinal image in order to obtain a set of candidate regions to be Ex, which are validated by means of feature extraction and supervised classification techniques. The diagnoses provided by the system on 1058 retinographies of 529 diabetic patients at risk of having DME show that the system can operate at a level of sensitivity comparable to that of ophthalmological specialists: it achieved 0.9000 sensitivity per patient against 0.7733, 0.9133 and 0.9000 of several specialists, where the false negatives were mild clinical cases of the disease. In addition, the level of specificity reached by the system was 0.6939, high enough to screen about 70% of the patients with no evidence of DME. These values show that the system fulfils the requirements for its possible integration into a complete diabetic retinopathy pre-screening tool for the automated management of patients within a screening programme. Graphical Abstract Diagnosis system of risk of diabetic macular edema (DME) based on exudate (Ex) detection in fundus images.

Specificity of antibodies directed against the cytolethal distending toxin of Haemophilus ducreyi in patients with chancroid.

PubMed

Mbwana, Judica; Ahmed, Hinda J; Ahlman, Karin; Sundaeus, Vivian; Dahlén, Gunnar; Lyamuya, Eligius; Lagergård, Teresa

2003-09-01

Antibodies specific for the cytolethal-distending toxin of Haemophilus ducreyi (HdCDT) complex and for the CdtA, CdtB, and CdtC components were measured by ELISA in the sera of 50 patients with culture and/or PCR proven chancroid, 42 patients with periodontitis, 50 blood donors from Tanzania, 50 blood donors from Sweden. In addition, the biological activity e.g. neutralization capacity of the sera were tested. Our results demonstrate that majority of chancroid patients and healthy individuals had detectable levels of serum antibodies to HdCDT complex and to separate toxin components. However, high levels (> or =100 units) of antibodies to HdCDT complex were significantly more prevalent in the sera of patients with both chancroid and periodontitis than in the sera of the corresponding controls (P=0.001 and P=0.04, respectively). In the sera of the 50 patients with chancroid, antibodies to CdtA, CdtB, and CdtC were detected in 50, 35, and 34 individuals, respectively. Antibodies to CdtC, being less frequently detected than the antibodies to other components, show a good correlation with the neutralizing capacity of sera. High levels of neutralizing antibodies (> or =160) were detected in only 22 and 2% of the patients with chancroid and periodontitis, respectively. The data suggest that the low levels of anti-HdCDT antibodies, which include neutralizing antibodies, may contribute to limited protection in chancroid and since anti-HdCDT antibodies, may be detected in healthy individuals and in patients with certain disease conditions (e.g. periodontitis), they may not be specific markers for chancroid infection.

Assessment of the non-Gaussianity and non-linearity levels of simulated sEMG signals on stationary segments.

PubMed

Messaoudi, Noureddine; Bekka, Raïs El'hadi; Ravier, Philippe; Harba, Rachid

2017-02-01

The purpose of this paper was to evaluate the effects of the longitudinal single differential (LSD), the longitudinal double differential (LDD) and the normal double differential (NDD) spatial filters, the electrode shape, the inter-electrode distance (IED) on non-Gaussianity and non-linearity levels of simulated surface EMG (sEMG) signals when the maximum voluntary contraction (MVC) varied from 10% to 100% by a step of 10%. The effects of recruitment range thresholds (RR), the firing rate (FR) strategy and the peak firing rate (PFR) of motor units were also considered. A cylindrical multilayer model of the volume conductor and a model of motor unit (MU) recruitment and firing rate were used to simulate sEMG signals in a pool of 120 MUs for 5s. Firstly, the stationarity of sEMG signals was tested by the runs, the reverse arrangements (RA) and the modified reverse arrangements (MRA) tests. Then the non-Gaussianity was characterised with bicoherence and kurtosis, and non-linearity levels was evaluated with linearity test. The kurtosis analysis showed that the sEMG signals detected by the LSD filter were the most Gaussian and those detected by the NDD filter were the least Gaussian. In addition, the sEMG signals detected by the LSD filter were the most linear. For a given filter, the sEMG signals detected by using rectangular electrodes were more Gaussian and more linear than that detected with circular electrodes. Moreover, the sEMG signals are less non-Gaussian and more linear with reverse onion-skin firing rate strategy than those with onion-skin strategy. The levels of sEMG signal Gaussianity and linearity increased with the increase of the IED, RR and PFR. Copyright © 2016 Elsevier Ltd. All rights reserved.

Elevated Plasma IL-6 Associates with Increased Risk of Advanced Fibrosis and Cholangiocarcinoma in Individuals Infected by Opisthorchis viverrini

PubMed Central

Sripa, Banchob; Thinkhamrop, Bandit; Mairiang, Eimorn; Laha, Thewarach; Kaewkes, Sasithorn; Sithithaworn, Paiboon; Periago, Maria Victoria; Bhudhisawasdi, Vajarabhongsa; Yonglitthipagon, Ponlapat; Mulvenna, Jason; Brindley, Paul J.; Loukas, Alex; Bethony, Jeffrey M.

2012-01-01

Opisthorchis viverrini is considered among the most important of the food-borne trematodes due to its strong association with advanced periductal fibrosis and bile duct cancer (cholangiocarcinoma). We investigated the relationship between plasma levels of Interleukin (IL)-6 and the risk of developing advanced fibrosis and bile duct cancer from chronic Opisthorchis infection. We show that IL-6 circulates in plasma at concentrations 58 times higher in individuals with advanced fibrosis than age, sex, and nearest-neighbor matched controls and 221 times higher in individuals with bile duct cancer than controls. We also observed a dose-response relationship between increasing levels of plasma IL-6 and increasing risk of advanced fibrosis and bile duct cancer; for example, in age and sex adjusted analyses, individuals with the highest quartiles of plasma IL-6 had a 19 times greater risk of developing advanced periductal fibrosis and a 150 times greater risk of developing of bile duct cancer than individuals with no detectable level of plasma IL-6. Finally, we show that a single plasma IL-6 measurement has excellent positive predictive value for the detection of both advanced bile duct fibrosis and bile duct cancer in regions with high O. viverrini transmission. These data support our hypothesis that common mechanisms drive bile duct fibrosis and bile duct tumorogenesis from chronic O. viverrini infection. Our study also adds a unique aspect to the literature on circulating levels of IL-6 as an immune marker of hepatobiliary pathology by showing that high levels of circulating IL-6 in plasma are not related to infection with O. viverrini, but to the development of the advanced and often lethal pathologies resulting from chronic O. viverrini infection. PMID:22629477

Laser induced fluorescence lifetime characterization of Bacillus endospore species using time correlated single photon counting analysis with the multi-exponential fit method

NASA Astrophysics Data System (ADS)

Smith, Clint; Edwards, Jarrod; Fisher, Andmorgan

2010-04-01

Rapid detection of biological material is critical for determining presence/absence of bacterial endospores within various investigative programs. Even more critical is that if select material tests positive for bacillus endospores then tests should provide data at the species level. Optical detection of microbial endospore formers such as Bacillus sp. can be heavy, cumbersome, and may only identify at the genus level. Data provided from this study will aid in characterization needed by future detection systems for further rapid breakdown analysis to gain insight into a more positive signature collection of Bacillus sp. Literature has shown that fluorescence spectroscopy of endospores could be statistically separated from other vegetative genera, but could not be separated among one another. Results of this study showed endospore species separation is possible using laser-induce fluorescence with lifetime decay analysis for Bacillus endospores. Lifetime decays of B. subtilis, B. megaterium, B. coagulans, and B. anthracis Sterne strain were investigated. Using the Multi-Exponential fit method data showed three distinct lifetimes for each species within the following ranges, 0.2-1.3 ns; 2.5-7.0 ns; 7.5-15.0 ns, when laser induced at 307 nm. The four endospore species were individually separated using principle component analysis (95% CI).

An Optimal Bahadur-Efficient Method in Detection of Sparse Signals with Applications to Pathway Analysis in Sequencing Association Studies.

PubMed

Dai, Hongying; Wu, Guodong; Wu, Michael; Zhi, Degui

2016-01-01

Next-generation sequencing data pose a severe curse of dimensionality, complicating traditional "single marker-single trait" analysis. We propose a two-stage combined p-value method for pathway analysis. The first stage is at the gene level, where we integrate effects within a gene using the Sequence Kernel Association Test (SKAT). The second stage is at the pathway level, where we perform a correlated Lancaster procedure to detect joint effects from multiple genes within a pathway. We show that the Lancaster procedure is optimal in Bahadur efficiency among all combined p-value methods. The Bahadur efficiency,[Formula: see text], compares sample sizes among different statistical tests when signals become sparse in sequencing data, i.e. ε →0. The optimal Bahadur efficiency ensures that the Lancaster procedure asymptotically requires a minimal sample size to detect sparse signals ([Formula: see text]). The Lancaster procedure can also be applied to meta-analysis. Extensive empirical assessments of exome sequencing data show that the proposed method outperforms Gene Set Enrichment Analysis (GSEA). We applied the competitive Lancaster procedure to meta-analysis data generated by the Global Lipids Genetics Consortium to identify pathways significantly associated with high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, and total cholesterol.

Leaky phenotype of X-linked agammaglobulinaemia in a Japanese family

PubMed Central

Kaneko, H; Kawamoto, N; Asano, T; Mabuchi, Y; Horikoshi, H; Teramoto, T; JIN-RONG; Matsui, E; Kondo, M; Fukao, T; Kasahara, K; Kondo, N

2005-01-01

X-linked agammaglobulinaemia (XLA) is an inherited immunodeficiency that is caused by a block in early B-cell differentiation. Whereas early B precursors in the bone marrow are present in substantial numbers, XLA-affected individuals have dramatically reduced numbers of circulating mature B cells, plasma cells and immunoglobulins of all isotypes. We report on a Japanese family with 3 XLA patients, in whom the serum immunoglobulin levels and number of B cells showed a significant difference among them in spite of harbouring the same splice donor site mutation in the BTK gene. We developed concise method for detection of this mutation, which is helpful for discovering the carrier. Patient 2 showed a significant serum immunoglobulin levels of all isotypes, including allergen-specific IgE. Expression of a normal and truncated size BTK gene was detected in patient 2′s peripheral blood mononuclear cells (PBMCs). Expression of BTK protein was also detected in some B cells. These results suggest that the leaky phenotype in patient 2 was caused in part by the expression of a normal BTK gene transcript. The increased frequency of infection with age expanded the number of B cells with normal BTK gene expression and produced the serum immunoglobulin, including IgE. PMID:15932514

Efficient photoconductive terahertz detector with all-dielectric optical metasurface

NASA Astrophysics Data System (ADS)

Mitrofanov, Oleg; Siday, Thomas; Thompson, Robert J.; Luk, Ting Shan; Brener, Igal; Reno, John L.

2018-05-01

We designed an optically thin photoconductive channel as an all-dielectric metasurface comprising an array of low-temperature grown GaAs nanobeams and a sub-surface distributed Bragg reflector. The metasurface exhibited enhanced optical absorption, and it was integrated into a photoconductive THz detector, which showed high efficiency and sensitivity as a result. The detector produced photocurrents over one order of magnitude higher compared to a similar detector with an unstructured surface with only 0.5 mW of optical excitation while exhibiting high dark resistance required for low-noise detection in THz time-domain spectroscopy and imaging. At that level of optical excitation, the metasurface detector showed a high signal to noise ratio of 106. The detector showed saturation above that level.

[Expression of Chemokine receptor CXCR6 and its significance in breast cancer cell lines].

PubMed

Cheng, Hao; Chen, Nian-yong

2014-05-01

To detect the expression of Chemokine receptor CXCR6 in invasive breast cancer cell lines and normal mammary epithelial cell line, and assess the relationship between CXCR6 expression and malignant behavior of breast cancer cells. Expression level of CXCR6 in different invasive breast cancer cell lines (SK-BR-3, MCF-7, MDA-MB-231) and normal mammary epithelial cell line (MCF-10A)was detected by real time reverse transcription-polymerase chain reaction (real time-PCR) and Western blot. Lentivirus was employed to interfere CXCR6 expression in MDA-MB-231. MTT assay and transwell chamber were used to study proliferative and invasive ability of those cells respectively. Vascular enothelial growth factor (VEGF) expression was detected to study the role of CXCR6 in angiogenesis. At both mRNA level and protein level, normal mammary epithelial cell line MCF-10A showed the weakest CXCR6 expression. The breast cancer cell lines expressed CXCR6 in different levels, the expression level of CXCR6 in highly invasive cell line MDA-MB-231 was significantly higher than that in two low-invasive cell lines SK-BR-3 and MCF-7 (P < 0.05). Silencing CXCR6 gene by Lentivirus-mediated RNA interference in MDA-MB-231 inhibited its proliferation ability, invasion ability and angiogenesis ability in vitro (P < 0.05). Different invasive breast cancer cell lines express CXCR6 at different levels, positively correlated with its invasive ability.

Organochlorine contaminants in eggs of common terns from the Canadian Great Lakes 1981

USGS Publications Warehouse

Weseloh, D.V.; Custer, T.W.; Braune, B.M.

1989-01-01

To determine if contaminant levels in common terns had changed over the last decade, we collected and analyzed eggs from four nesting colonies on the three lower Great lakes during 1981. DDE and PCBs were detected in every egg from the four colonies. Dieldrin, mirex and trans-nonachlor were detected in more than 45% of the eggs. Seven other organochlorine contaminants (DDD, DDT, hexachlorobenzene, oxychlordane, cis-chlordane, cis-nonachlor and toxaphene) were detected in less than 25% of the eggs. Eggs from the Lake Ontario colony were generally the most heavily contaminated. Comparisons of DDE and PCB data with earlier studies of common terns indicated that contaminant levels in eggs from the four sampled colonies, or nearby sites, have decreased by up to 80-90% from 1969-73 to 1981. Interspecies comparisons showed that common tern eggs have lower organochlorine residue levels than eggs of caspian terns or herring gulls. Dietary variation and migratory status are possible explanations for the differences in residue levels among species. Eggshell thickness, log-PCBs, and log-DDE were not significantly intercorrelated. Elevated contaminant levels in the early 1970s might be at least partly responsible for the decline of the Great Lakes Common Tern population over the past decade. Stabilization of population numbers during the early 1980s suggests that organochlorine pollution levels have been reduced to a point where they are no longer an important factor in the population dynamics of this species on the Great Lakes.

A Portable and Autonomous Magnetic Detection Platform for Biosensing

PubMed Central

Germano, José; Martins, Verónica C.; Cardoso, Filipe A.; Almeida, Teresa M.; Sousa, Leonel; Freitas, Paulo P.; Piedade, Moisés S.

2009-01-01

This paper presents a prototype of a platform for biomolecular recognition detection. The system is based on a magnetoresistive biochip that performs biorecognition assays by detecting magnetically tagged targets. All the electronic circuitry for addressing, driving and reading out signals from spin-valve or magnetic tunnel junctions sensors is implemented using off-the-shelf components. Taking advantage of digital signal processing techniques, the acquired signals are processed in real time and transmitted to a digital analyzer that enables the user to control and follow the experiment through a graphical user interface. The developed platform is portable and capable of operating autonomously for nearly eight hours. Experimental results show that the noise level of the described platform is one order of magnitude lower than the one presented by the previously used measurement set-up. Experimental results also show that this device is able to detect magnetic nanoparticles with a diameter of 250 nm at a concentration of about 40 fM. Finally, the biomolecular recognition detection capabilities of the platform are demonstrated by performing a hybridization assay using complementary and non-complementary probes and a magnetically tagged 20mer single stranded DNA target. PMID:22408516

A Simple, Cost-Effective Sensor for Detecting Lead Ions in Water Using Under-Potential Deposited Bismuth Sub-Layer with Differential Pulse Voltammetry (DPV)

PubMed Central

Dai, Yifan; Liu, Chung Chiun

2017-01-01

This research has developed a simple to use, cost effective sensor system for the detection of lead ions in tap water. An under-potential deposited bismuth sub-layer on a thin gold film based electrochemical sensor was designed, manufactured, and evaluated. Differential pulse voltammetry (DPV) measurement technique was employed in this detection. Tap water from the Cleveland, OH, USA regional water district was the test medium. Concentrations of lead ion in the range of 8 × 10−7 M to 5 × 10−4 M were evaluated, showing a good sensitivity over this concentration range. The calibration curve for the DPV measurements of lead ions in tap water showed excellent reproducibility with R2 value of 0.970. This DPV detection system required 3–6 min to complete the detection measurement. A longer measurement time of 6 min was used for the lower lead ion concentration. The selectivity of this lead ion sensor was very good, and Fe III, Cu II, Ni II, and Mg II at a concentration level of 5 × 10−4 M did not interfere with the lead ion measurement. PMID:28441356

Detection of MDM2/CDK4 amplification in lipomatous soft tissue tumors from formalin-fixed, paraffin-embedded tissue: comparison of multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridization (FISH).

PubMed

Creytens, David; van Gorp, Joost; Ferdinande, Liesbeth; Speel, Ernst-Jan; Libbrecht, Louis

2015-02-01

In this study, the detection of MDM2 and CDK4 amplification was evaluated in lipomatous soft tissue tumors using multiplex ligation-dependent probe amplification (MLPA), a PCR-based technique, in comparison with fluorescence in situ hybridization (FISH). These 2 techniques were evaluated in a series of 77 formalin-fixed, paraffin-embedded lipomatous tumors (27 benign adipose tumors, 28 atypical lipomatous tumors/well-differentiated liposarcomas, 18 dedifferentiated liposarcomas, and 4 pleomorphic liposarcomas). Using MLPA, with a cut-off ratio of >2, 36/71 samples (22 atypical lipomatous tumors/well-differentiated liposarcomas, and 14 dedifferentiated liposarcomas) showed MDM2 and CDK4 amplification. Using FISH as gold standard, MLPA showed a sensitivity of 90% (36/40) and a specificity of 100% (31/31) in detecting amplification of MDM2 and CDK4 in lipomatous soft tissue tumors. In case of high-level amplification (MDM2-CDK4/CEP12 ratio >5), concordance was 100%. Four cases of atypical lipomatous tumor/well-differentiated liposarcoma (4/26, 15%) with a low MDM2 and CDK4 amplification level (MDM2-CDK4/CEP12 ratio ranging between 2 and 2.5) detected by FISH showed no amplification by MLPA, although gain of MDM2 and CDK4 (ratios ranging between 1.6 and 1.9) was seen with MLPA. No amplification was detected in benign lipomatous tumors and pleomorphic liposarcomas. Furthermore, there was a very high concordance between the ratios obtained by FISH and MLPA. In conclusion, MLPA proves to be an appropriate and straightforward technique for screening MDM2/CDK4 amplification in lipomatous tumors, especially when a correct cut-off value and reference samples are chosen, and could be considered a good alternative to FISH to determine MDM2 and CDK4 amplification in liposarcomas. Moreover, because MLPA, as a multiplex technique, allows simultaneous detection of multiple chromosomal changes of interest, it could be in the future a very reliable and fast molecular analysis on paraffin-embedded material to test for other diagnostically, prognostically, or therapeutically relevant genomic mutations in lipomatous tumors.

a Cloud Boundary Detection Scheme Combined with Aslic and Cnn Using ZY-3, GF-1/2 Satellite Imagery

NASA Astrophysics Data System (ADS)

Guo, Z.; Li, C.; Wang, Z.; Kwok, E.; Wei, X.

2018-04-01

Remote sensing optical image cloud detection is one of the most important problems in remote sensing data processing. Aiming at the information loss caused by cloud cover, a cloud detection method based on convolution neural network (CNN) is presented in this paper. Firstly, a deep CNN network is used to extract the multi-level feature generation model of cloud from the training samples. Secondly, the adaptive simple linear iterative clustering (ASLIC) method is used to divide the detected images into superpixels. Finally, the probability of each superpixel belonging to the cloud region is predicted by the trained network model, thereby generating a cloud probability map. The typical region of GF-1/2 and ZY-3 were selected to carry out the cloud detection test, and compared with the traditional SLIC method. The experiment results show that the average accuracy of cloud detection is increased by more than 5 %, and it can detected thin-thick cloud and the whole cloud boundary well on different imaging platforms.

Simultaneous determination of eight major steroids from Polyporus umbellatus by high-performance liquid chromatography coupled with mass spectrometry detections.

PubMed

Zhao, Ying-yong; Cheng, Xian-long; Zhang, Yongmin; Zhao, Ye; Lin, Rui-chao; Sun, Wen-ji

2010-02-01

Polyporus umbellatus is a widely used diuretic herbal medicine. In this study, a high-performance liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometric detection (HPLC-APCI-MS) method was developed for qualitative and quantitative analysis of steroids, as well as for the quality control of Polyporus umbellatus. The selectivity, reproducibility and sensitivity were compared with HPLC with photodiode array detection and evaporative light scattering detection (ELSD). Selective ion monitoring in positive mode was used for qualitative and quantitative analysis of eight major components and beta-ecdysterone was used as the internal standard. Limits of detection and quantification fell in the ranges 7-21 and 18-63 ng/mL for the eight analytes with an injection of 10 microL samples, and all calibration curves showed good linear regression (r(2) > 0.9919) within the test range. The quantitative results demonstrated that samples from different localities showed different qualities. Advantages, in comparison with conventional HPLC-diode array detection and HPLC-ELSD, are that reliable identification of target compounds could be achieved by accurate mass measurements along with characteristic retention time, and the great enhancement in selectivity and sensitivity allows identification and quantification of low levels of constituents in complex Polyporus umbellatus matrixes. (c) 2009 John Wiley & Sons, Ltd.

Detection of the multiphoton signals in stained tissue using nonlinear optical microscopy

NASA Astrophysics Data System (ADS)

Zeng, Yaping; Xu, Jian; Kang, Deyong; Lin, Jiangbo; Chen, Jianxin

2016-10-01

Multiphoton microscopy (MPM) based on two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) imaging, has become a powerful, important tool for tissue imaging at the molecular level. Recently, MPM is also used to image hematoxylin and eosin (H and E)-stained sections in cancer diagnostics. However, several studies have showed that the MPM images of tissue stained with H and E are significantly different from unstained tissue sections. Our aim was to detect of the multiphoton signals in stained tissue by using MPM. In this paper, MPM was used to image histological sections of esophageal invasive carcinoma tissues stained with H, E, H and E and fresh tissue. To detect of the multiphoton signals in stained tissue, the emission spectroscopic of tissue stained with H, E, H and E were obtained. For comparison, the fresh tissues were also investigated. Our results showed that the tissue stained with H, E, H and E could be detected by their TPEF signals. While the tissue stained with H and fresh tissue could be detected by their TPEF and SHG signals. In this work, we detect of the multiphoton signals in stained tissue. These findings will be useful for choosing suitable staining method so to improve the quality of MPM imaging in the future.

Curiosity Finds Hydrogen-Rich Area of Mars Subsurface

NASA Image and Video Library

2015-08-19

Curiosity's Russian-made instrument for checking hydration levels in the ground beneath the rover detected an unusually high amount at a site near "Marias Pass," prompting repeated passes over the area to map the hydrogen amounts. The instrument is named Dynamic Albedo of Neutrons, or DAN. It detects hydrogen by the effect of hydrogen atoms on neutrons entering the ground either from cosmic rays and Curiosity's power source (DAN's passive mode) or from the instrument's neutron pulse generator (DAN's active mode). DAN recognizes which neutrons have bounced off hydrogen from their rerduced energy level. This map, covering an area about 130 feet (40 meters) across, shows results from DAN's multiple traverses over the area, with color coding for levels of hydrogen detected. The red coding indicates amounts of hydrogen three to four times as high as the amounts detected anywhere previously along Curiosity's traverse of about 6.9 miles (11.1 kilometers) since landing in August 2012. The inset map at lower right shows the full traverse through Sol 1051 (July 21, 2015), with names assigned to rectangles within Gale Crater for geological mapping purposes. The vertical bar at left indicates the color coding according to counts per second in DAN's passive mode. The hydrogen detected by DAN is interpreted as water molecules or hydroxyl ions bound within minerals or water absorbed onto minerals in the rocks and soil, to a depth of about 3 feet (1 meter) beneath the rover. The amount of hydrogen is often expressed as "water equivalent hydrogen" based on two hydrogen atoms per molecule of water. In the same area where DAN detected an unusually high amount of hydration, Curiosity's Chemistry and Camera (ChemCam) instrument detected an unusually high amount of silica in several rock targets. The DAN and ChemCam findings led to the rover's science team choosing a rock target called "Buckskin" for collection of a drilled sample to be analyzed by the rover's internal laboratory instruments. Russia's Space Research Institute developed DAN in close cooperation with the N.L. Dukhov All-Russia Research Institute of Automatics, Moscow, and the Joint Institute for Nuclear Research, Dubna. The neutron generator development was supervised by the late technical designer German A. Smirnov of the All-Russia Institute of Automatics. Moscow. http://photojournal.jpl.nasa.gov/catalog/PIA19809

Detection of Prostate Cancer: Quantitative Multiparametric MR Imaging Models Developed Using Registered Correlative Histopathology.

PubMed

Metzger, Gregory J; Kalavagunta, Chaitanya; Spilseth, Benjamin; Bolan, Patrick J; Li, Xiufeng; Hutter, Diane; Nam, Jung W; Johnson, Andrew D; Henriksen, Jonathan C; Moench, Laura; Konety, Badrinath; Warlick, Christopher A; Schmechel, Stephen C; Koopmeiners, Joseph S

2016-06-01

Purpose To develop multiparametric magnetic resonance (MR) imaging models to generate a quantitative, user-independent, voxel-wise composite biomarker score (CBS) for detection of prostate cancer by using coregistered correlative histopathologic results, and to compare performance of CBS-based detection with that of single quantitative MR imaging parameters. Materials and Methods Institutional review board approval and informed consent were obtained. Patients with a diagnosis of prostate cancer underwent multiparametric MR imaging before surgery for treatment. All MR imaging voxels in the prostate were classified as cancer or noncancer on the basis of coregistered histopathologic data. Predictive models were developed by using more than one quantitative MR imaging parameter to generate CBS maps. Model development and evaluation of quantitative MR imaging parameters and CBS were performed separately for the peripheral zone and the whole gland. Model accuracy was evaluated by using the area under the receiver operating characteristic curve (AUC), and confidence intervals were calculated with the bootstrap procedure. The improvement in classification accuracy was evaluated by comparing the AUC for the multiparametric model and the single best-performing quantitative MR imaging parameter at the individual level and in aggregate. Results Quantitative T2, apparent diffusion coefficient (ADC), volume transfer constant (K(trans)), reflux rate constant (kep), and area under the gadolinium concentration curve at 90 seconds (AUGC90) were significantly different between cancer and noncancer voxels (P < .001), with ADC showing the best accuracy (peripheral zone AUC, 0.82; whole gland AUC, 0.74). Four-parameter models demonstrated the best performance in both the peripheral zone (AUC, 0.85; P = .010 vs ADC alone) and whole gland (AUC, 0.77; P = .043 vs ADC alone). Individual-level analysis showed statistically significant improvement in AUC in 82% (23 of 28) and 71% (24 of 34) of patients with peripheral-zone and whole-gland models, respectively, compared with ADC alone. Model-based CBS maps for cancer detection showed improved visualization of cancer location and extent. Conclusion Quantitative multiparametric MR imaging models developed by using coregistered correlative histopathologic data yielded a voxel-wise CBS that outperformed single quantitative MR imaging parameters for detection of prostate cancer, especially when the models were assessed at the individual level. (©) RSNA, 2016 Online supplemental material is available for this article.

Correlation between STK33 and the pathology and prognosis of lung cancer

PubMed Central

Lu, Yi; Tang, Jie; Zhang, Wenmei; Shen, Ce; Xu, Ling; Yang, Danrong

2017-01-01

Correlation between the expression of STK33 and the pathology of lung cancer was investigated, to explore its effects on prognosis. Hundred and two lung cancer patients diagnosed by pathological examinations were randomly selected in Shanghai Jiao Tong University Affiliated Sixth People's Hospital from February, 2012 to February, 2017 to serve as observation group, and the tumor tissues were collected. At the same time, 19 patients with lung benign lesions were selected and lung tissues were also collected to serve as control group. RT-qPCR was used to detect the expression of STK33 mRNA in tissues. Expression levels of STK33 protein were detected and compared by SP immunohistochemistry staining and western blot analysis. Statistical analysis was performed to analyze the correlation between STK33 expression and the pathology and prognosis of lung cancer. Results of PCR showed that expression level of STK33 gene in control group was significantly lower than that in observation group (p<0.05). The expression level of STK33 mRNA in lung adenocarcinoma and squamous cell carcinoma was lower than that in lung small cell carcinoma and large cell carcinoma (p<0.05). Western blot analysis showed that the expression level of STK33 protein in lung small cell carcinoma and large cell carcinoma was significantly higher than that in lung adenocarcinoma and squamous cell carcinoma (p<0.05). Immunohistochemistry staining showed that the positive rate of STK33 in lung large cell carcinoma (100%) and small cell carcinoma (100%) was significantly higher than that in lung adenocarcinoma (88.1%) and squamous cell carcinoma (86.2%) (p<0.05). The 5-year survival rate analysis showed that the recurrence-free survival rate and overall survival rate of STK33 gene high expression level group were significantly lower than those of low expression level group (p<0.05). The differential expression level of STK33 is related to the pathology and prognosis of lung cancer, which is of great value in clinical diagnosis and prognosis evaluation. PMID:29085482

Introducing two Random Forest based methods for cloud detection in remote sensing images

NASA Astrophysics Data System (ADS)

Ghasemian, Nafiseh; Akhoondzadeh, Mehdi

2018-07-01

Cloud detection is a necessary phase in satellite images processing to retrieve the atmospheric and lithospheric parameters. Currently, some cloud detection methods based on Random Forest (RF) model have been proposed but they do not consider both spectral and textural characteristics of the image. Furthermore, they have not been tested in the presence of snow/ice. In this paper, we introduce two RF based algorithms, Feature Level Fusion Random Forest (FLFRF) and Decision Level Fusion Random Forest (DLFRF) to incorporate visible, infrared (IR) and thermal spectral and textural features (FLFRF) including Gray Level Co-occurrence Matrix (GLCM) and Robust Extended Local Binary Pattern (RELBP_CI) or visible, IR and thermal classifiers (DLFRF) for highly accurate cloud detection on remote sensing images. FLFRF first fuses visible, IR and thermal features. Thereafter, it uses the RF model to classify pixels to cloud, snow/ice and background or thick cloud, thin cloud and background. DLFRF considers visible, IR and thermal features (both spectral and textural) separately and inserts each set of features to RF model. Then, it holds vote matrix of each run of the model. Finally, it fuses the classifiers using the majority vote method. To demonstrate the effectiveness of the proposed algorithms, 10 Terra MODIS and 15 Landsat 8 OLI/TIRS images with different spatial resolutions are used in this paper. Quantitative analyses are based on manually selected ground truth data. Results show that after adding RELBP_CI to input feature set cloud detection accuracy improves. Also, the average cloud kappa values of FLFRF and DLFRF on MODIS images (1 and 0.99) are higher than other machine learning methods, Linear Discriminate Analysis (LDA), Classification And Regression Tree (CART), K Nearest Neighbor (KNN) and Support Vector Machine (SVM) (0.96). The average snow/ice kappa values of FLFRF and DLFRF on MODIS images (1 and 0.85) are higher than other traditional methods. The quantitative values on Landsat 8 images show similar trend. Consequently, while SVM and K-nearest neighbor show overestimation in predicting cloud and snow/ice pixels, our Random Forest (RF) based models can achieve higher cloud, snow/ice kappa values on MODIS and thin cloud, thick cloud and snow/ice kappa values on Landsat 8 images. Our algorithms predict both thin and thick cloud on Landsat 8 images while the existing cloud detection algorithm, Fmask cannot discriminate them. Compared to the state-of-the-art methods, our algorithms have acquired higher average cloud and snow/ice kappa values for different spatial resolutions.

Automated detection of photoreceptor disruption in mild diabetic retinopathy on volumetric optical coherence tomography

PubMed Central

Wang, Zhuo; Camino, Acner; Zhang, Miao; Wang, Jie; Hwang, Thomas S.; Wilson, David J.; Huang, David; Li, Dengwang; Jia, Yali

2017-01-01

Diabetic retinopathy is a pathology where microvascular circulation abnormalities ultimately result in photoreceptor disruption and, consequently, permanent loss of vision. Here, we developed a method that automatically detects photoreceptor disruption in mild diabetic retinopathy by mapping ellipsoid zone reflectance abnormalities from en face optical coherence tomography images. The algorithm uses a fuzzy c-means scheme with a redefined membership function to assign a defect severity level on each pixel and generate a probability map of defect category affiliation. A novel scheme of unsupervised clustering optimization allows accurate detection of the affected area. The achieved accuracy, sensitivity and specificity were about 90% on a population of thirteen diseased subjects. This method shows potential for accurate and fast detection of early biomarkers in diabetic retinopathy evolution. PMID:29296475

Detecting gradual visual changes in colour and brightness agnosia: a double dissociation.

PubMed

Nijboer, Tanja C W; te Pas, Susan F; van der Smagt, Maarten J

2011-03-09

Two patients, one with colour agnosia and one with brightness agnosia, performed a task that required the detection of gradual temporal changes in colour and brightness. The results for these patients, who showed anaverage or an above-average performance on several tasks designed to test low-level colour and luminance (contrast) perception in the spatial domain, yielded a double dissociation; the brightness agnosic patient was within the normal range for the coloured stimuli, but much slower to detect brightness differences, whereas the colour agnosic patient was within the normal range for the achromatic stimuli, but much slower for the coloured stimuli. These results suggest that a modality-specific impairment in the detection of gradual temporal changes might be related to, if not underlie, the phenomenon of visual agnosia.

Seismic detection and analysis of icequakes at Columbia Glacier, Alaska

USGS Publications Warehouse

O'Neel, Shad; Marshall, Hans P.; McNamara, Daniel E.; Pfeffer, William Tad

2007-01-01

Contributions to sea level rise from rapidly retreating marine-terminating glaciers are large and increasing. Strong increases in iceberg calving occur during retreat, which allows mass transfer to the ocean at a much higher rate than possible through surface melt alone. To study this process, we deployed an 11-sensor passive seismic network at Columbia Glacier, Alaska, during 2004–2005. We show that calving events generate narrow-band seismic signals, allowing frequency domain detections. Detection parameters were determined using direct observations of calving and validated using three statistical methods and hypocenter locations. The 1–3 Hz detections provide a good measure of the temporal distribution and size of calving events. Possible source mechanisms for the unique waveforms are discussed, and we analyze potential forcings for the observed seismicity.

Automated detection of photoreceptor disruption in mild diabetic retinopathy on volumetric optical coherence tomography.

PubMed

Wang, Zhuo; Camino, Acner; Zhang, Miao; Wang, Jie; Hwang, Thomas S; Wilson, David J; Huang, David; Li, Dengwang; Jia, Yali

2017-12-01

Diabetic retinopathy is a pathology where microvascular circulation abnormalities ultimately result in photoreceptor disruption and, consequently, permanent loss of vision. Here, we developed a method that automatically detects photoreceptor disruption in mild diabetic retinopathy by mapping ellipsoid zone reflectance abnormalities from en face optical coherence tomography images. The algorithm uses a fuzzy c-means scheme with a redefined membership function to assign a defect severity level on each pixel and generate a probability map of defect category affiliation. A novel scheme of unsupervised clustering optimization allows accurate detection of the affected area. The achieved accuracy, sensitivity and specificity were about 90% on a population of thirteen diseased subjects. This method shows potential for accurate and fast detection of early biomarkers in diabetic retinopathy evolution.

Fold-change detection and scalar symmetry of sensory input fields.

PubMed

Shoval, Oren; Goentoro, Lea; Hart, Yuval; Mayo, Avi; Sontag, Eduardo; Alon, Uri

2010-09-07

Recent studies suggest that certain cellular sensory systems display fold-change detection (FCD): a response whose entire shape, including amplitude and duration, depends only on fold changes in input and not on absolute levels. Thus, a step change in input from, for example, level 1 to 2 gives precisely the same dynamical output as a step from level 2 to 4, because the steps have the same fold change. We ask what the benefit of FCD is and show that FCD is necessary and sufficient for sensory search to be independent of multiplying the input field by a scalar. Thus, the FCD search pattern depends only on the spatial profile of the input and not on its amplitude. Such scalar symmetry occurs in a wide range of sensory inputs, such as source strength multiplying diffusing/convecting chemical fields sensed in chemotaxis, ambient light multiplying the contrast field in vision, and protein concentrations multiplying the output in cellular signaling systems. Furthermore, we show that FCD entails two features found across sensory systems, exact adaptation and Weber's law, but that these two features are not sufficient for FCD. Finally, we present a wide class of mechanisms that have FCD, including certain nonlinear feedback and feed-forward loops. We find that bacterial chemotaxis displays feedback within the present class and hence, is expected to show FCD. This can explain experiments in which chemotaxis searches are insensitive to attractant source levels. This study, thus, suggests a connection between properties of biological sensory systems and scalar symmetry stemming from physical properties of their input fields.

Hydrogeological investigation at Site 5, Willow Grove Naval Air Station/Joint Reserve Base, Horsham Township, Montgomery County, Pennsylvania

USGS Publications Warehouse

Sloto, Ronald A.

2002-01-01

The U.S. Geological Survey conducted borehole geophysical logging, collected and analyzed water-level data, and sampled sections of a rock core to determine the concentration of volatile organic compounds in the aquifer matrix of the Stockton Formation. Borehole geophysical logs were run in three monitor wells. At well 05MW04I, the vertical gradient was upward at depths above 42 feet below land surface (ft bls), downward between 42 and 82 ft bls, and upward below 82 ft bls. At well 05MW05I, a downward vertical gradient was present. At well 05MW12I, the vertical gradient was downward above 112 ft bls and upward below 112 ft bls.Three water-bearing fractures in a 17-foot long rock core from 23.5 to 40.5 ft bls were identified and sampled. Three samples were analyzed from each water-bearing fracture—at the fracture face, 2 centimeters (cm) below the fracture, and 4 cm below the fracture. Fifteen compounds were detected; however, concentrations of seven compounds were less than 1 microgram per kilogram (mg/kg) when detected. Concentrations of benzene (from 0.39 to 3.3 mg/kg), 1,1-dichloroethene (1,1-DCE) (from 0.15 to 13 mg/kg), 1,1,1-trichloroethane (TCA) (from 0.17 to 22 mg/kg), and trichloroethylene (TCE) (from 0.092 to 9.6 mg/kg) were detected in all samples. The highest concentrations detected were for toluene, which was detected at a concentration of 32 and 86 mg/kg in the samples from unweathered sandstone at 2 and 4 cm below the fracture, respectively. Concentrations generally decreased with distance below the fracture in the mudstone samples. Concentrations of benzene and toluene increased with distance below the fractures in the unweathered sandstone samples. Concentrations of 1,1-DCE, TCA, and TCE were higher in the mudstone samples than in the samples from sandstone. Toluene concentrations were higher in unweathered sandstone than in weathered sandstone or mudstone.The effect of the pumping of Horsham Water and Sewer Authority public supply well 26 (HWSA-26), 0.2 mile southwest of the base boundary, on groundwater levels on the base was determined by shutting the well down for 6 days to allow water levels to recover. Water levels in 22 nearby wells were measured. The only well (02MW01I) that showed an unambiguous response to the shutdown of well HWSA-26 is 1,350 feet directly along strike from well HWSA-26. The recovery of well 05MW11I in response to the shutdown of well HWSA-26 is masked by recharge from snowmelt but probably does not exceed about 0.2 feet on the basis of the water level in well 05MW11I, which showed a response to the pumping of well HWSA-26 that ranged from 0.5 to 0.15 foot.Horizontal gradients differ with depth, and the rate and direction of ground-water flow and contaminant movement is depth dependent. The potentiometric-surface map for water levels measured in wells screened between 5 and 44 ft bls in the aquifer shows a ground-water mound that is the high point on a regional ground-water divide. From this divide, ground water flows both northwest toward Park Creek and southeast toward Pennypack Creek. The hydraulic gradient around this mound is relatively flat to the southeast and particularly flat to the northwest. The potentiometric-surface map for water levels measured in wells screened between 40 and 100 ft bls in the aquifer shows a very flat hydraulic gradient. Differences in the elevation of the potentiometric surface are less than 2 feet. The potentiometric-surface map for water levels measured in wells screened between 105 and 179 ft bls in the aquifer shows a steep hydraulic gradient between Sites 5 and 2 and a relatively flat hydraulic gradient between Sites 5 and 3. Water levels measured on October 7, 1999, showed downward vertical head gradients for all well clusters at Site 5. Vertical gradients ranged from 0.01 at well cluster 05MW10 to 0.2 at cluster 05MW11. Most gradients were between 0.01 and 0.026. Vertical head gradients vary with time. The variability is caused by a difference in the magnitude of water-level fluctuations between shallow and the deep fractures. The difference in the magnitude of water-level fluctuations is because of differences in lithology and aquifer storativity.

Segregating the neural correlates of physical and perceived change in auditory input using the change deafness effect.

PubMed

Puschmann, Sebastian; Weerda, Riklef; Klump, Georg; Thiel, Christiane M

2013-05-01

Psychophysical experiments show that auditory change detection can be disturbed in situations in which listeners have to monitor complex auditory input. We made use of this change deafness effect to segregate the neural correlates of physical change in auditory input from brain responses related to conscious change perception in an fMRI experiment. Participants listened to two successively presented complex auditory scenes, which consisted of six auditory streams, and had to decide whether scenes were identical or whether the frequency of one stream was changed between presentations. Our results show that physical changes in auditory input, independent of successful change detection, are represented at the level of auditory cortex. Activations related to conscious change perception, independent of physical change, were found in the insula and the ACC. Moreover, our data provide evidence for significant effective connectivity between auditory cortex and the insula in the case of correctly detected auditory changes, but not for missed changes. This underlines the importance of the insula/anterior cingulate network for conscious change detection.

Epidemic failure detection and consensus for extreme parallelism

DOE PAGES

Katti, Amogh; Di Fatta, Giuseppe; Naughton, Thomas; ...

2017-02-01

Future extreme-scale high-performance computing systems will be required to work under frequent component failures. The MPI Forum s User Level Failure Mitigation proposal has introduced an operation, MPI Comm shrink, to synchronize the alive processes on the list of failed processes, so that applications can continue to execute even in the presence of failures by adopting algorithm-based fault tolerance techniques. This MPI Comm shrink operation requires a failure detection and consensus algorithm. This paper presents three novel failure detection and consensus algorithms using Gossiping. The proposed algorithms were implemented and tested using the Extreme-scale Simulator. The results show that inmore » all algorithms the number of Gossip cycles to achieve global consensus scales logarithmically with system size. The second algorithm also shows better scalability in terms of memory and network bandwidth usage and a perfect synchronization in achieving global consensus. The third approach is a three-phase distributed failure detection and consensus algorithm and provides consistency guarantees even in very large and extreme-scale systems while at the same time being memory and bandwidth efficient.« less

Selective and Sensitive Detection of Heavy Metal Ions in 100% Aqueous Solution and Cells with a Fluorescence Chemosensor Based on Peptide Using Aggregation-Induced Emission.

PubMed

Neupane, Lok Nath; Oh, Eun-Taex; Park, Heon Joo; Lee, Keun-Hyeung

2016-03-15

A fluorescent peptidyl chemosensor for the detection of heavy metal ions in aqueous solution as well as in cells was synthesized on the basis of the peptide receptor for the metal ions using an aggregation-induced emission fluorophore. The peptidyl chemosensor (1) bearing tetraphenylethylene fluorophore showed an exclusively selective turn-on response to Hg(2+) among 16 metal ions in aqueous buffered solution containing NaCl. The peptidyl chemosensor complexed Hg(2+) ions and then aggregated in aqueous buffered solution, resulting in the significant enhancement (OFF-On) of emissions at around 470 nm. The fluorescent sensor showed a highly sensitive response to Hg(2+), and about 1.0 equiv of Hg(2+) was enough for the saturation of the emission intensity change. The detection limit (5.3 nM, R(2) = 0.99) of 1 for Hg(2+) ions was lower than the maximum allowable level of Hg(2+) in drinking water by EPA. Moreover, the peptidyl chemosensor penetrated live cells and detected intracellular Hg(2+) ions by the turn-on response.

Digitally encoded DNA nanostructures for multiplexed, single-molecule protein sensing with nanopores

NASA Astrophysics Data System (ADS)

Bell, Nicholas A. W.; Keyser, Ulrich F.

2016-07-01

The simultaneous detection of a large number of different analytes is important in bionanotechnology research and in diagnostic applications. Nanopore sensing is an attractive method in this regard as the approach can be integrated into small, portable device architectures, and there is significant potential for detecting multiple sub-populations in a sample. Here, we show that highly multiplexed sensing of single molecules can be achieved with solid-state nanopores by using digitally encoded DNA nanostructures. Based on the principles of DNA origami, we designed a library of DNA nanostructures in which each member contains a unique barcode; each bit in the barcode is signalled by the presence or absence of multiple DNA dumbbell hairpins. We show that a 3-bit barcode can be assigned with 94% accuracy by electrophoretically driving the DNA structures through a solid-state nanopore. Select members of the library were then functionalized to detect a single, specific antibody through antigen presentation at designed positions on the DNA. This allows us to simultaneously detect four different antibodies of the same isotype at nanomolar concentration levels.