A Fast Framework for Abrupt Change Detection Based on Binary Search Trees and Kolmogorov Statistic.

PubMed

Qi, Jin-Peng; Qi, Jie; Zhang, Qing

2016-01-01

Change-Point (CP) detection has attracted considerable attention in the fields of data mining and statistics; it is very meaningful to discuss how to quickly and efficiently detect abrupt change from large-scale bioelectric signals. Currently, most of the existing methods, like Kolmogorov-Smirnov (KS) statistic and so forth, are time-consuming, especially for large-scale datasets. In this paper, we propose a fast framework for abrupt change detection based on binary search trees (BSTs) and a modified KS statistic, named BSTKS (binary search trees and Kolmogorov statistic). In this method, first, two binary search trees, termed as BSTcA and BSTcD, are constructed by multilevel Haar Wavelet Transform (HWT); second, three search criteria are introduced in terms of the statistic and variance fluctuations in the diagnosed time series; last, an optimal search path is detected from the root to leaf nodes of two BSTs. The studies on both the synthetic time series samples and the real electroencephalograph (EEG) recordings indicate that the proposed BSTKS can detect abrupt change more quickly and efficiently than KS, t-statistic (t), and Singular-Spectrum Analyses (SSA) methods, with the shortest computation time, the highest hit rate, the smallest error, and the highest accuracy out of four methods. This study suggests that the proposed BSTKS is very helpful for useful information inspection on all kinds of bioelectric time series signals.

Ontogenetic Development of Weberian Ossicles and Hearing Abilities in the African Bullhead Catfish

PubMed Central

Lechner, Walter; Heiss, Egon; Schwaha, Thomas; Glösmann, Martin; Ladich, Friedrich

2011-01-01

Background The Weberian apparatus of otophysine fishes facilitates sound transmission from the swimbladder to the inner ear to increase hearing sensitivity. It has been of great interest to biologists since the 19th century. No studies, however, are available on the development of the Weberian ossicles and its effect on the development of hearing in catfishes. Methodology/Principal Findings We investigated the development of the Weberian apparatus and auditory sensitivity in the catfish Lophiobagrus cyclurus. Specimens from 11.3 mm to 85.5 mm in standard length were studied. Morphology was assessed using sectioning, histology, and X-ray computed tomography, along with 3D reconstruction. Hearing thresholds were measured utilizing the auditory evoked potentials recording technique. Weberian ossicles and interossicular ligaments were fully developed in all stages investigated except in the smallest size group. In the smallest catfish, the intercalarium and the interossicular ligaments were still missing and the tripus was not yet fully developed. Smallest juveniles revealed lowest auditory sensitivity and were unable to detect frequencies higher than 2 or 3 kHz; sensitivity increased in larger specimens by up to 40 dB, and frequency detection up to 6 kHz. In the size groups capable of perceiving frequencies up to 6 kHz, larger individuals had better hearing abilities at low frequencies (0.05–2 kHz), whereas smaller individuals showed better hearing at the highest frequencies (4–6 kHz). Conclusions/Significance Our data indicate that the ability of otophysine fish to detect sounds at low levels and high frequencies largely depends on the development of the Weberian apparatus. A significant increase in auditory sensitivity was observed as soon as all Weberian ossicles and interossicular ligaments are present and the chain for transmitting sounds from the swimbladder to the inner ear is complete. This contrasts with findings in another otophysine, the zebrafish, where no threshold changes have been observed. PMID:21533262

GRE T2∗-Weighted MRI: Principles and Clinical Applications

PubMed Central

Tang, Meng Yue; Chen, Tian Wu; Zhang, Xiao Ming; Huang, Xiao Hua

2014-01-01

The sequence of a multiecho gradient recalled echo (GRE) T2*-weighted imaging (T2*WI) is a relatively new magnetic resonance imaging (MRI) technique. In contrast to T2 relaxation, which acquires a spin echo signal, T2* relaxation acquires a gradient echo signal. The sequence of a GRE T2*WI requires high uniformity of the magnetic field. GRE T2*WI can detect the smallest changes in uniformity in the magnetic field and can improve the rate of small lesion detection. In addition, the T2* value can indirectly reflect changes in tissue biochemical components. Moreover, it can be used for the early diagnosis and quantitative diagnosis of some diseases. This paper reviews the principles and clinical applications as well as the advantages and disadvantages of GRE T2*WI. PMID:24987676

Individualized quality of life in patients with low back pain: reliability and validity of the Patient Generated Index.

PubMed

Løchting, Ida; Grotle, Margreth; Storheim, Kjersti; Werner, Erik L; Garratt, Andrew M

2014-09-01

To evaluate the reliability and validity of the improved version of the Patient Generated Index (PGI) in patients with low back pain. The PGI was administered to 90 patients attending care in 1 of 6 institutions in Norway and evaluated for reliability and validity. The questionnaire was given out to 61 patients for re-test purposes. The PGI was completed correctly by 80 (88.9%) patients and, of the 61 patients responding to the re-test, 50 (82.0%) completed both surveys correctly. PGI scores were approximately normally distributed, with a median of 40 (range 80), where 100 is the best possible quality of life. There were no floor or ceiling effects. The 5 most frequently listed areas affecting quality of life were pain, sleep, stiffness, socializing and housework. The test-retest intraclass correlation coefficient was 0.73. The smallest detectable changes for individual and group purposes were 32.8 and 4.6, respectively. The correlations between PGI scores and other instrument scores followed a priori hypotheses of low to moderate correlations. The PGI has evidence for reliability and validity in Norwegian patients with low back pain at the group level and may be considered for application in intervention studies when a comprehensive evaluation of quality of life is important. However, the smallest detectable change, of approximately 30 points, may be considered too large for individual purposes in clinical applications.

Longitudinal white matter change in frontotemporal dementia subtypes and sporadic late onset Alzheimer's disease.

PubMed

Elahi, Fanny M; Marx, Gabe; Cobigo, Yann; Staffaroni, Adam M; Kornak, John; Tosun, Duygu; Boxer, Adam L; Kramer, Joel H; Miller, Bruce L; Rosen, Howard J

2017-01-01

Degradation of white matter microstructure has been demonstrated in frontotemporal lobar degeneration (FTLD) and Alzheimer's disease (AD). In preparation for clinical trials, ongoing studies are investigating the utility of longitudinal brain imaging for quantification of disease progression. To date only one study has examined sample size calculations based on longitudinal changes in white matter integrity in FTLD. To quantify longitudinal changes in white matter microstructural integrity in the three canonical subtypes of frontotemporal dementia (FTD) and AD using diffusion tensor imaging (DTI). 60 patients with clinical diagnoses of FTD, including 27 with behavioral variant frontotemporal dementia (bvFTD), 14 with non-fluent variant primary progressive aphasia (nfvPPA), and 19 with semantic variant PPA (svPPA), as well as 19 patients with AD and 69 healthy controls were studied. We used a voxel-wise approach to calculate annual rate of change in fractional anisotropy (FA) and mean diffusivity (MD) in each group using two time points approximately one year apart. Mean rates of change in FA and MD in 48 atlas-based regions-of-interest, as well as global measures of cognitive function were used to calculate sample sizes for clinical trials (80% power, alpha of 5%). All FTD groups showed statistically significant baseline and longitudinal white matter degeneration, with predominant involvement of frontal tracts in the bvFTD group, frontal and temporal tracts in the PPA groups and posterior tracts in the AD group. Longitudinal change in MD yielded a larger number of regions with sample sizes below 100 participants per therapeutic arm in comparison with FA. SvPPA had the smallest sample size based on change in MD in the fornix (n = 41 participants per study arm to detect a 40% effect of drug), and nfvPPA and AD had their smallest sample sizes based on rate of change in MD within the left superior longitudinal fasciculus (n = 49 for nfvPPA, and n = 23 for AD). BvFTD generally showed the largest sample size estimates (minimum n = 140 based on MD in the corpus callosum). The corpus callosum appeared to be the best region for a potential study that would include all FTD subtypes. Change in global measure of functional status (CDR box score) yielded the smallest sample size for bvFTD (n = 71), but clinical measures were inferior to white matter change for the other groups. All three of the canonical subtypes of FTD are associated with significant change in white matter integrity over one year. These changes are consistent enough that drug effects in future clinical trials could be detected with relatively small numbers of participants. While there are some differences in regions of change across groups, the genu of the corpus callosum is a region that could be used to track progression in studies that include all subtypes.

Spatial heterogeneity in statistical power to detect changes in lake area in Alaskan National Wildlife Refuges

USGS Publications Warehouse

Nicol, Samuel; Roach, Jennifer K.; Griffith, Brad

2013-01-01

Over the past 50 years, the number and size of high-latitude lakes have decreased throughout many regions; however, individual lake trends have been variable in direction and magnitude. This spatial heterogeneity in lake change makes statistical detection of temporal trends challenging, particularly in small analysis areas where weak trends are difficult to separate from inter- and intra-annual variability. Factors affecting trend detection include inherent variability, trend magnitude, and sample size. In this paper, we investigated how the statistical power to detect average linear trends in lake size of 0.5, 1.0 and 2.0 %/year was affected by the size of the analysis area and the number of years of monitoring in National Wildlife Refuges in Alaska. We estimated power for large (930–4,560 sq km) study areas within refuges and for 2.6, 12.9, and 25.9 sq km cells nested within study areas over temporal extents of 4–50 years. We found that: (1) trends in study areas could be detected within 5–15 years, (2) trends smaller than 2.0 %/year would take >50 years to detect in cells within study areas, and (3) there was substantial spatial variation in the time required to detect change among cells. Power was particularly low in the smallest cells which typically had the fewest lakes. Because small but ecologically meaningful trends may take decades to detect, early establishment of long-term monitoring will enhance power to detect change. Our results have broad applicability and our method is useful for any study involving change detection among variable spatial and temporal extents.

[Middle ear salivary gland choristoma related to branchio-oto-renal syndrome diagnosed by array-CGH].

PubMed

Amrhein, P; Sittel, C; Spaich, C; Kohlhase, J; Boppert, R; Kohlhof, P; Koitschev, A

2014-05-01

Branchio-oto-renal (BOR) syndrome is characterized by ear malformations associated with sensorineural or mixed hearing loss. In addition, preauricular tags, preauricular pits, branchial cleft fistulas and cysts, as well as renal dysplasia are seen. A genetic mutation on chromosome 8, either autosomal dominantly inherited or occuring as a spontaneous mutation, is the cause in the majority of cases. Using array-based comparative genomic hybridization (CGH), it is possible to detect even the smallest genetic changes. Salivary gland choristoma in the middle ear is very rare. Surgical removal and histological clarification are required.

Electromagnetic microscope compared with a conventional pulsed eddy-current probe

NASA Astrophysics Data System (ADS)

Podney, Walter N.

1998-03-01

A superconductive probe presently can detect a crack at a rivet hole that is two to three times smaller than the smallest crack detectable by a conventional probe. As the technology matures and noise resolution approaches a limit set by SQUIDS, approximately 1 fH, it will enable detecting submillimeter cracks down to approximately 15 mm.

[An intriguing model for 5S rDNA sequences dispersion in the genome of freshwater stingray Potamotrygon motoro (Chondrichthyes: Potamotrygonidae)].

PubMed

Cruz, V P; Oliveira, C; Foresti, F

2015-01-01

5S rDNA genes of the stingray Potamotrygon motoro were PCR replicated, purified, cloned and sequenced. Two distinct classes of segments of different sizes were obtained. The smallest, with 342 bp units, was classified as class I, and the largest, with 1900 bp units, was designated as class II. Alignment with the consensus sequences for both classes showed changes in a few bases in the 5S rDNA genes. TATA-like sequences were detected in the nontranscribed spacer (NTS) regions of class I and a microsatellite (GCT) 10 sequence was detected in the NTS region of class II. The results obtained can help to understand the molecular organization of ribosomal genes and the mechanism of gene dispersion.

Concurrent validity and reliability of wireless instrumented insoles measuring postural balance and temporal gait parameters.

PubMed

Oerbekke, Michiel S; Stukstette, Mirelle J; Schütte, Kurt; de Bie, Rob A; Pisters, Martijn F; Vanwanseele, Benedicte

2017-01-01

The OpenGo seems promising to take gait analysis out of laboratory settings due to its capability of long-term measurements and mobility. However, the OpenGo's concurrent validity and reliability need to be assessed to determine if the instrument is suitable for validation in patient samples. Twenty healthy volunteers participated. Center of pressure data were collected under eyes open and closed conditions with participants performing unilateral stance trials on the gold standard (AMTI OR6-7 force plate) while wearing the OpenGo. Temporal gait data (stance time, gait cycle time, and cadence) were collected at a self-selected comfortable walking speed with participants performing test-retest trials on an instrumented treadmill while wearing the OpenGo. Validity was assessed using Bland-Altman plots. Reliability was assessed with Intraclass Correlation Coefficient (2,1) and smallest detectable changes were calculated. Negative means of differences were found in all measured parameters, illustrating lower scores for the OpenGo on average. The OpenGo showed negative upper limits of agreement in center of pressure parameters on the mediolateral axis. Temporal reliability ICCs ranged from 0.90-0.93. Smallest detectable changes for both stance times were 0.04 (left) and 0.05 (right) seconds, for gait cycle time 0.08s, and for cadence 4.5 steps per minute. The OpenGo is valid and reliable for the measurement of temporal gait parameters during walking. Measurements of center of pressure parameters during unilateral stance are not considered valid. The OpenGo seems a promising instrument for clinically screening and monitoring temporal gait parameters in patients, however validation in patient populations is needed. Copyright © 2016 Elsevier B.V. All rights reserved.

Translation, Cross-Cultural Adaptation, and Validation of the Activity Rating Scale for Disorders of the Knee.

PubMed

Flosadottir, Vala; Roos, Ewa M; Ageberg, Eva

2017-09-01

The Activity Rating Scale (ARS) for disorders of the knee evaluates the level of activity by the frequency of participation in 4 separate activities with high demands on knee function, with a score ranging from 0 (none) to 16 (pivoting activities 4 times/wk). To translate and cross-culturally adapt the ARS into Swedish and to assess measurement properties of the Swedish version of the ARS. Cohort study (diagnosis); Level of evidence, 2. The COSMIN guidelines were followed. Participants (N = 100 [55 women]; mean age, 27 years) who were undergoing rehabilitation for a knee injury completed the ARS twice for test-retest reliability. The Knee injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Scale (TAS), and modernized Saltin-Grimby Physical Activity Level Scale (SGPALS) were administered at baseline to validate the ARS. Construct validity and responsiveness of the ARS were evaluated by testing predefined hypotheses regarding correlations between the ARS, KOOS, TAS, and SGPALS. The Cronbach alpha, intraclass correlation coefficients, absolute reliability, standard error of measurement, smallest detectable change, and Spearman rank-order correlation coefficients were calculated. The ARS showed good internal consistency (α ≈ 0.96), good test-retest reliability (intraclass correlation coefficient >0.9), and no systematic bias between measurements. The standard error of measurement was less than 2 points, and the smallest detectable change was less than 1 point at the group level and less than 5 points at the individual level. More than 75% of the hypotheses were confirmed, indicating good construct validity and good responsiveness of the ARS. The Swedish version of the ARS is valid, reliable, and responsive for evaluating the level of activity based on the frequency of participation in high-demand knee sports activities in young adults with a knee injury.

The influence of image position on urban place detection

NASA Technical Reports Server (NTRS)

Haralick, R. M. (Principal Investigator)

1973-01-01

The author has identified the following significant results. The ability of ERTS-1 MSS imagery to detect small urban places appears to vary with the position of the place in the image, as well as from band to band. Urban places of smallest size (approximately 2000 population) seem more detectable in the westernmost 3.5 degree scan segment. A relationship may exist between shadowing of vertical features and detectability.

Encephalomyocarditis Virus Ribonucleic Acid Polymerase Associated with 150S Cytoplasmic Particles

PubMed Central

Bases, Robert; Tarikas, Helgi

1969-01-01

Cytoplasmic particles which sedimented at 150S were the smallest structures containing detectable viral ribonucleic acid polymerase in mouse cells infected with encephalomyocarditis virus. PMID:4307906

Test-Retest Reliability of the Self-Reported Impairments in Persons With Late Effects of Polio (SIPP) Rating Scale.

PubMed

Brogårdh, Christina; Lexell, Jan

2016-05-01

A new 13-item rating scale, the Self-Reported Impairments in Persons with Late Effects of Polio (SIPP), has been developed. The SIPP has been analyzed using the Rasch method and has shown good construct validity and internal consistency. To establish its clinical utility, further evaluation of its psychometric properties is needed. To evaluate the test-retest reliability of the SIPP and to define limits for the smallest change that indicates a real change, both for a group of persons and a single individual. A postal survey. University Hospital. Fifty-one persons (31 men and 20 women; mean age, 72 years) with clinically verified late effects of polio. Not applicable. The participants completed the SIPP twice, 2 weeks apart. The response frequencies at test occasion 1 (T1) and test occasion 2 (T2) were calculated. Test-retest reliability was analyzed using the percentage agreement of each item, the intraclass correlation coefficient, and the mean difference between the test occasions (đ), together with the 95% confidence intervals for đ, the standard error of measurement, the smallest real difference, and a Bland-Altman plot. The percentage agreement (ie, the same scoring at both test occasions) was >70% for 10 of 13 items. The mean score (standard deviation) was 27.9 (5.7) points at T1 and 28.2 (6.0) points at T2, with no systematic difference between the test occasions. The intraclass correlation coefficient was 0.88, the standard error of measurement (the smallest change for a group of persons) was 2.0 points, and the smallest real difference (the smallest change for a single individual) was 5.6 points, respectively. The SIPP is a reliable rating scale in persons with late effects of polio and can be used to evaluate effects of rehabilitation interventions and changes of perceived impairments over time both for a group of persons and for a single individual. Copyright © 2016 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.

AAVSO Solar Observers Worldwide

NASA Astrophysics Data System (ADS)

Howe, R.

2013-06-01

(Abstract only) For visual solar observers there has been no biological change in the "detector" (human eye) - at century scales (eye + visual cortex) does not change much over time. Our capacity to "integrate" seeing distortions is not just simple averaging! The visual cortex plays an essential role, and until recently only the SDO-HMI (Solar Dynamics Observatory, Helioseismic and Magnetic Imager) has had the capacity to detect the smallest sunspots, called pores. Prior to this the eye was superior to photography and CCD. Imaged data are not directly comparable or substitutable to counts by eye, as the effects of sensor/optical resolution and seeing will have a different influence on the resulting sunspot counts for images when compared to the human eye. Also contributing to the complex task of counting sunspots is differentiating between a sunspot (which is usually defined as having a darker center (umbra) and lighter outer ring (penumbra)) and a pore, made even more complex by the conflicting definitions of the word "pore" in the solar context: "pore" can mean a small spot without penumbra or "pore" can mean a random intergranular blemish that is not a true sunspot. The overall agreement is that the smallest spot size is near 2,000 km or ~3 arc sec, (Loughhead, R. E. and Bray, R. J. 1961, Australian J. Phys., 14, 347). Sunspot size is dictated by granulation dynamics rather than spot size (cancellation of convective motion), and by the lifetime of the pore, which averages from 10 to 30 minutes. There is no specific aperture required for AAVSO observers contributing sunspot observations. However, the detection of the smallest spots is influenced by the resolution of the telescope. Two factors to consider are the theoretical optical resolution (unobstructed aperture), Rayleigh criterion: theta = 138 / D(mm), and Dawes criterion: theta = 116 / D(mm) (http://www.telescope-optics.net/telescope_resolution.htm). However, seeing is variable with time; daytime range will be similar for all low-altitude sites, within the range of 1.5 to 3 arc sec, (typically = 2 arc sec equivalent diameter D = 45-90 mm, the typical solar scope = 70 mm aperture). Where large apertures are more affected by size of turbulent eddies ~8-12 cm, small-aperture telescopes reduce these differences, i.e. large aperture is not always beneficial.

Suppression of nucleation mode particles by biomass burning in an urban environment: a case study.

PubMed

Agus, Emily L; Lingard, Justin J N; Tomlin, Alison S

2008-08-01

Measurements of concentrations and size distributions of particles 4.7 to 160 nm were taken using an SMPS during the bonfire and firework celebrations on Bonfire Night in Leeds, UK, 2006. These celebrations provided an opportunity to study size distributions in a unique atmospheric pollution situation during and following a significant emission event due to open biomass burning. A log-normal fitting program was used to determine the characteristics of the modal groups present within hourly averaged size distributions. Results from the modal fitting showed that on bonfire night the smallest nucleation mode, which was present before and after the bonfire event and on comparison weekends, was not detected within the size distribution. In addition, there was a significant shift in the modal diameters of the remaining modes during the peak of the pollution event. Using the concept of a coagulation sink, the atmospheric lifetimes of smaller particles were significantly reduced during the pollution event, and thus were used to explain the disappearance of the smallest nucleation mode as well as changes in particle count mean diameters. The significance for particle mixing state is discussed.

Fetal programming of fat and collagen in porcine skeletal muscles

PubMed Central

Karunaratne, JF; Ashton, CJ; Stickland, NC

2005-01-01

Connective tissue plays a key role in the scaffolding and development of skeletal muscle. Pilot studies carried out in our laboratory have shown that the smallest porcine littermate has a higher content of connective tissue within skeletal muscle compared with its largest littermate. The present study investigated the prenatal development of intralitter variation in terms of collagen content within connective tissue and intramuscular fat of the M. semitendinosus. Twenty-three pairs of porcine fetuses from a Large White–Landrace origin were used aged from 36 to 86 days of gestation. The largest and smallest littermates were chosen by weight and the M. semitendinosus was removed from each. Complete transverse muscle sections were stained with Oil Red O (detection of lipids) and immunocytochemistry was performed using an antibody to collagen I. Slides were analysed and paired t-Tests revealed the smallest littermate contained a significantly higher proportion of fat deposits and collagen I content compared with the largest littermate. Recent postnatal studies showing elevated levels of intramuscular lipids and low scores for meat tenderness in the smallest littermate corroborate our investigations. It can be concluded that the differences seen in connective tissue elements have a fetal origin that may continue postnatally. PMID:16367803

Implementation of a channelized Hotelling observer model to assess image quality of x-ray angiography systems.

PubMed

Favazza, Christopher P; Fetterly, Kenneth A; Hangiandreou, Nicholas J; Leng, Shuai; Schueler, Beth A

2015-01-01

Evaluation of flat-panel angiography equipment through conventional image quality metrics is limited by the scope of standard spatial-domain image quality metric(s), such as contrast-to-noise ratio and spatial resolution, or by restricted access to appropriate data to calculate Fourier domain measurements, such as modulation transfer function, noise power spectrum, and detective quantum efficiency. Observer models have been shown capable of overcoming these limitations and are able to comprehensively evaluate medical-imaging systems. We present a spatial domain-based channelized Hotelling observer model to calculate the detectability index (DI) of our different sized disks and compare the performance of different imaging conditions and angiography systems. When appropriate, changes in DIs were compared to expectations based on the classical Rose model of signal detection to assess linearity of the model with quantum signal-to-noise ratio (SNR) theory. For these experiments, the estimated uncertainty of the DIs was less than 3%, allowing for precise comparison of imaging systems or conditions. For most experimental variables, DI changes were linear with expectations based on quantum SNR theory. DIs calculated for the smallest objects demonstrated nonlinearity with quantum SNR theory due to system blur. Two angiography systems with different detector element sizes were shown to perform similarly across the majority of the detection tasks.

Preliminary Comparisons of the Information Content and Utility of TM Versus MSS Data

NASA Technical Reports Server (NTRS)

Markham, B. L.

1984-01-01

Comparisons were made between subscenes from the first TM scene acquired of the Washington, D.C. area and a MSS scene acquired approximately one year earlier. Three types of analyses were conducted to compare TM and MSS data: a water body analysis, a principal components analysis and a spectral clustering analysis. The water body analysis compared the capability of the TM to the MSS for detecting small uniform targets. Of the 59 ponds located on aerial photographs 34 (58%) were detected by the TM with six commission errors (15%) and 13 (22%) were detected by the MSS with three commission errors (19%). The smallest water body detected by the TM was 16 meters; the smallest detected by the MSS was 40 meters. For the principal components analysis, means and covariance matrices were calculated for each subscene, and principal components images generated and characterized. In the spectral clustering comparison each scene was independently clustered and the clusters were assigned to informational classes. The preliminary comparison indicated that TM data provides enhancements over MSS in terms of (1) small target detection and (2) data dimensionality (even with 4-band data). The extra dimension, partially resultant from TM band 1, appears useful for built-up/non-built-up area separation.

Local Leak Detection and Health Monitoring of Pressurized Tanks

NASA Technical Reports Server (NTRS)

Polzin, Kurt; Witherow, William; Korman, Valentin; Sinko, John; Hendrickson, Adam

2011-01-01

An optical gas-detection sensor safely monitors pressurized systems (such as cryogenic tanks) and distribution systems for leaks. This sensor system is a fiber-coupled, solid optical body interferometer that allows for the miniaturized sensing element of the device to be placed in the smallest of recesses, and measures a wide range of gas species and densities (leaks). The deflection of the fringe pattern is detected and recorded to yield the time-varying gas density in the gap. This technology can be used by manufacturers or storage facilities with toxic, hazardous, or explosive gases. The approach is to monitor the change in the index of refraction associated with low-level gas leaks into a vacuum environment. The completion of this work will provide NASA with an enabling capability to detect gas system leaks in space, and to verify that pressurized systems are in a safe (i.e. non-leaking) condition during manned docking and transit operations. By recording the output of the sensor, a time-history of the leak can be constructed to indicate its severity. Project risk is mitigated by having several interferometric geometries and detection techniques available, each potentially leveraging hardware and lessons learned to enhance detectability.

Detecting and collecting traces of semen and blood from outdoor crime scenes using crime scene dogs and presumptive tests.

PubMed

Skalleberg, A G; Bouzga, M M

2016-07-01

In 2009, the Norwegian police academy educated their first crime scene dogs, trained to locate traces of seminal fluid and blood in outdoor and indoor crime scenes. The Department of Forensic Biology was invited to take part in this project to educate the police in specimen collection and presumptive testing. We performed tests where seminal fluid was deposited on different outdoor surfaces from between one hour to six days, and blood on coniferous ground from between one hour to two days. For both body fluids the tests were performed with three different volumes. The crime scene dogs located the stains, and acid phosphatase/tetrabasebariumperoxide was used as presumptive tests before collection for microscopy and DNA analysis. For seminal fluid the dogs were able to locate all stains for up to two days and only the largest volume after four days. The presumptive tests confirmed the dog's detection. By microscopy we were able to detect spermatozoa for the smallest volumes up to 32h, and for the largest volume up to 4 days, and the DNA results are in correlation to these findings. For blood all the stains were detected by the dogs, except the smallest volume of blood after 32h. The presumptive tests confirmed the dog's detection. We were able to get DNA results for most stains in the timeframe 1-48h with the two largest volumes. The smallest volume shows diversities between the parallels, with no DNA results after 24h. These experiments show that it is critical that body fluids are collected within a timeframe to be able to get a good DNA result, preferably within the first 24-48h. Other parameters that should be taken into account are the weather conditions, type of surfaces and specimen collection. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Spatial vision processes: From the optical image to the symbolic structures of contour information

NASA Technical Reports Server (NTRS)

Jobson, Daniel J.

1988-01-01

The significance of machine and natural vision is discussed together with the need for a general approach to image acquisition and processing aimed at recognition. An exploratory scheme is proposed which encompasses the definition of spatial primitives, intrinsic image properties and sampling, 2-D edge detection at the smallest scale, the construction of spatial primitives from edges, and the isolation of contour information from textural information. Concepts drawn from or suggested by natural vision at both perceptual and physiological levels are relied upon heavily to guide the development of the overall scheme. The scheme is intended to provide a larger context in which to place the emerging technology of detector array focal-plane processors. The approach differs from many recent efforts in edge detection and image coding by emphasizing smallest scale edge detection as a foundation for multi-scale symbolic processing while diminishing somewhat the importance of image convolutions with multi-scale edge operators. Cursory treatments of information theory illustrate that the direct application of this theory to structural information in images could not be realized.

Study of moving object detecting and tracking algorithm for video surveillance system

NASA Astrophysics Data System (ADS)

Wang, Tao; Zhang, Rongfu

2010-10-01

This paper describes a specific process of moving target detecting and tracking in the video surveillance.Obtain high-quality background is the key to achieving differential target detecting in the video surveillance.The paper is based on a block segmentation method to build clear background,and using the method of background difference to detecing moving target,after a series of treatment we can be extracted the more comprehensive object from original image,then using the smallest bounding rectangle to locate the object.In the video surveillance system, the delay of camera and other reasons lead to tracking lag,the model of Kalman filter based on template matching was proposed,using deduced and estimated capacity of Kalman,the center of smallest bounding rectangle for predictive value,predicted the position in the next moment may appare,followed by template matching in the region as the center of this position,by calculate the cross-correlation similarity of current image and reference image,can determine the best matching center.As narrowed the scope of searching,thereby reduced the searching time,so there be achieve fast-tracking.

Pitch discrimination accuracy in musicians vs nonmusicians: an event-related potential and behavioral study.

PubMed

Tervaniemi, Mari; Just, Viola; Koelsch, Stefan; Widmann, Andreas; Schröger, Erich

2005-02-01

Previously, professional violin players were found to automatically discriminate tiny pitch changes, not discriminable by nonmusicians. The present study addressed the pitch processing accuracy in musicians with expertise in playing a wide selection of instruments (e.g., piano; wind and string instruments). Of specific interest was whether also musicians with such divergent backgrounds have facilitated accuracy in automatic and/or attentive levels of auditory processing. Thirteen professional musicians and 13 nonmusicians were presented with frequent standard sounds and rare deviant sounds (0.8, 2, or 4% higher in frequency). Auditory event-related potentials evoked by these sounds were recorded while first the subjects read a self-chosen book and second they indicated behaviorally the detection of sounds with deviant frequency. Musicians detected the pitch changes faster and more accurately than nonmusicians. The N2b and P3 responses recorded during attentive listening had larger amplitude in musicians than in nonmusicians. Interestingly, the superiority in pitch discrimination accuracy in musicians over nonmusicians was observed not only with the 0.8% but also with the 2% frequency changes. Moreover, also nonmusicians detected quite reliably the smallest pitch changes of 0.8%. However, the mismatch negativity (MMN) and P3a recorded during a reading condition did not differentiate musicians and nonmusicians. These results suggest that musical expertise may exert its effects merely at attentive levels of processing and not necessarily already at the preattentive levels.

Translation, Cross-Cultural Adaptation, and Validation of the Activity Rating Scale for Disorders of the Knee

PubMed Central

Flosadottir, Vala; Roos, Ewa M.; Ageberg, Eva

2017-01-01

Background: The Activity Rating Scale (ARS) for disorders of the knee evaluates the level of activity by the frequency of participation in 4 separate activities with high demands on knee function, with a score ranging from 0 (none) to 16 (pivoting activities 4 times/wk). Purpose: To translate and cross-culturally adapt the ARS into Swedish and to assess measurement properties of the Swedish version of the ARS. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The COSMIN guidelines were followed. Participants (N = 100 [55 women]; mean age, 27 years) who were undergoing rehabilitation for a knee injury completed the ARS twice for test-retest reliability. The Knee injury and Osteoarthritis Outcome Score (KOOS), Tegner Activity Scale (TAS), and modernized Saltin-Grimby Physical Activity Level Scale (SGPALS) were administered at baseline to validate the ARS. Construct validity and responsiveness of the ARS were evaluated by testing predefined hypotheses regarding correlations between the ARS, KOOS, TAS, and SGPALS. The Cronbach alpha, intraclass correlation coefficients, absolute reliability, standard error of measurement, smallest detectable change, and Spearman rank-order correlation coefficients were calculated. Results: The ARS showed good internal consistency (α ≈ 0.96), good test-retest reliability (intraclass correlation coefficient >0.9), and no systematic bias between measurements. The standard error of measurement was less than 2 points, and the smallest detectable change was less than 1 point at the group level and less than 5 points at the individual level. More than 75% of the hypotheses were confirmed, indicating good construct validity and good responsiveness of the ARS. Conclusion: The Swedish version of the ARS is valid, reliable, and responsive for evaluating the level of activity based on the frequency of participation in high-demand knee sports activities in young adults with a knee injury. PMID:28979920

Test-retest reliability of biodex system 4 pro for isometric ankle-eversion and -inversion measurement.

PubMed

Tankevicius, Gediminas; Lankaite, Doanata; Krisciunas, Aleksandras

2013-08-01

The lack of knowledge about isometric ankle testing indicates the need for research in this area. to assess test-retest reliability and to determine the optimal position for isometric ankle-eversion and -inversion testing. Test-retest reliability study. Isometric ankle eversion and inversion were assessed in 3 different dynamometer foot-plate positions: 0°, 7°, and 14° of inversion. Two maximal repetitions were performed at each angle. Both limbs were tested (40 ankles in total). The test was performed 2 times with a period of 7 d between the tests. University hospital. The study was carried out on 20 healthy athletes with no history of ankle sprains. Reliability was assessed using intraclass correlation coefficient (ICC2,1); minimal detectable change (MDC) was calculated using a 95% confidence interval. Paired t test was used to measure statistically significant changes, and P <.05 was considered statistically significant. Eversion and inversion peak torques showed high ICCs in all 3 angles (ICC values .87-.96, MDC values 3.09-6.81 Nm). Eversion peak torque was the smallest when testing at the 0° angle and gradually increased, reaching maximum values at 14° angle. The increase of eversion peak torque was statistically significant at 7 ° and 14° of inversion. Inversion peak torque showed an opposite pattern-it was the smallest when measured at the 14° angle and increased at the other 2 angles; statistically significant changes were seen only between measures taken at 0° and 14°. Isometric eversion and inversion testing using the Biodex 4 Pro system is a reliable method. The authors suggest that the angle of 7° of inversion is the best for isometric eversion and inversion testing.

Implementation of a channelized Hotelling observer model to assess image quality of x-ray angiography systems

PubMed Central

Favazza, Christopher P.; Fetterly, Kenneth A.; Hangiandreou, Nicholas J.; Leng, Shuai; Schueler, Beth A.

2015-01-01

Abstract. Evaluation of flat-panel angiography equipment through conventional image quality metrics is limited by the scope of standard spatial-domain image quality metric(s), such as contrast-to-noise ratio and spatial resolution, or by restricted access to appropriate data to calculate Fourier domain measurements, such as modulation transfer function, noise power spectrum, and detective quantum efficiency. Observer models have been shown capable of overcoming these limitations and are able to comprehensively evaluate medical-imaging systems. We present a spatial domain-based channelized Hotelling observer model to calculate the detectability index (DI) of our different sized disks and compare the performance of different imaging conditions and angiography systems. When appropriate, changes in DIs were compared to expectations based on the classical Rose model of signal detection to assess linearity of the model with quantum signal-to-noise ratio (SNR) theory. For these experiments, the estimated uncertainty of the DIs was less than 3%, allowing for precise comparison of imaging systems or conditions. For most experimental variables, DI changes were linear with expectations based on quantum SNR theory. DIs calculated for the smallest objects demonstrated nonlinearity with quantum SNR theory due to system blur. Two angiography systems with different detector element sizes were shown to perform similarly across the majority of the detection tasks. PMID:26158086

Thermocouple design for measuring temperatures of small insects.

PubMed

Hanson, A A; Venette, R C

2013-01-01

Contact thermocouples often are used to measure surface body temperature changes of insects during cold exposure. However, small temperature changes of minute insects can be difficult to detect, particularly during the measurement of supercooling points. We developed two thermocouple designs, which use 0.51 mm diameter or 0.127 mm diameter copper-constantan wires, to improve our ability to resolve insect exotherms. We tested the designs with adults from three parasitoid species: Tetrastichus planipennisi, Spathius agrili, and S. floridanus. These species are <3 mm long and <0.1 mg. Mean exotherms were greater for fine-gauge thermocouples than thick-gauge thermocouples for the smallest species tested, T. planipennisi. This difference was not apparent for larger species S. agrili and S. floridanus. Thermocouple design did not affect the mean supercooling point for any of the species. The cradle thermocouple design developed with the fine gauge wire was reusable and allowed for easy insect recovery after cold exposure.

Investigation of detection limits for diffuse optical tomography systems: II. Analysis of slab and cup geometry for breast imaging.

PubMed

Ziegler, Ronny; Brendel, Bernhard; Rinneberg, Herbert; Nielsen, Tim

2009-01-21

Using a statistical (chi-square) test on simulated data and a realistic noise model derived from the system's hardware we study the performance of diffuse optical tomography systems for fluorescence imaging. We compare the predicted smallest size of detectable lesions at various positions in slab and cup geometry and model how detection sensitivity depends on breast compression and lesion fluorescence contrast. Our investigation shows that lesion detection is limited by relative noise in slab geometry and by absolute noise in cup geometry.

Detection limit of intragenic deletions with targeted array comparative genomic hybridization

PubMed Central

2013-01-01

Background Pathogenic mutations range from single nucleotide changes to deletions or duplications that encompass a single exon to several genes. The use of gene-centric high-density array comparative genomic hybridization (aCGH) has revolutionized the detection of intragenic copy number variations. We implemented an exon-centric design of high-resolution aCGH to detect single- and multi-exon deletions and duplications in a large set of genes using the OGT 60 K and 180 K arrays. Here we describe the molecular characterization and breakpoint mapping of deletions at the smaller end of the detectable range in several genes using aCGH. Results The method initially implemented to detect single to multiple exon deletions, was able to detect deletions much smaller than anticipated. The selected deletions we describe vary in size, ranging from over 2 kb to as small as 12 base pairs. The smallest of these deletions are only detectable after careful manual review during data analysis. Suspected deletions smaller than the detection size for which the method was optimized, were rigorously followed up and confirmed with PCR-based investigations to uncover the true detection size limit of intragenic deletions with this technology. False-positive deletion calls often demonstrated single nucleotide changes or an insertion causing lower hybridization of probes demonstrating the sensitivity of aCGH. Conclusions With optimizing aCGH design and careful review process, aCGH can uncover intragenic deletions as small as dozen bases. These data provide insight that will help optimize probe coverage in array design and illustrate the true assay sensitivity. Mapping of the breakpoints confirms smaller deletions and contributes to the understanding of the mechanism behind these events. Our knowledge of the mutation spectra of several genes can be expected to change as previously unrecognized intragenic deletions are uncovered. PMID:24304607

The nature of (sub-)micrometre cometary dust particles detected with MIDAS

NASA Astrophysics Data System (ADS)

Mannel, T.; Bentley, M. S.; Torkar, K.; Jeszenszky, H.; Romstedt, J.; Schmied, R.

2015-10-01

The MIDAS Atomic Force Microscope (AFM) onboard Rosetta collects dust particles and produces three-dimensional images with nano- to micrometre resolution. To date, several tens of particles have been detected, allowing determination of their properties at the smallest scale. The key features will be presented, including the particle size, their fragile character, and their morphology. These findings will be compared with the results of other Rosetta dust experiments.

Soil carbon inventories under a bioenergy crop (switchgrass): Measurement limitations

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

Garten, C.T. Jr.; Wullschleger, S.D.

Approximately 5 yr after planting, coarse root carbon (C) and soil organic C (SOC) inventories were compared under different types of plant cover at four switchgrass (Panicum virgatum L.) production field trials in the southeastern USA. There was significantly more coarse root C under switchgrass (Alamo variety) and forest cover than tall fescue (Festuca arundinacea Schreb.), corn (Zea mays L.), or native pastures of mixed grasses. Inventories of SOC under switchgrass were not significantly greater than SOC inventories under other plant covers. At some locations the statistical power associated with ANOVA of SOC inventories was low, which raised questions aboutmore » whether differences in SOC could be detected statistically. A minimum detectable difference (MDD) for SOC inventories was calculated. The MDD is the smallest detectable difference between treatment means once the variation, significance level, statistical power, and sample size are specified. The analysis indicated that a difference of {approx}50 mg SOC/cm{sup 2} or 5 Mg SOC/ha, which is {approx}10 to 15% of existing SOC, could be detected with reasonable sample sizes and good statistical power. The smallest difference in SOC inventories that can be detected, and only with exceedingly large sample sizes, is {approx}2 to 3%. These measurement limitations have implications for monitoring and verification of proposals to ameliorate increasing global atmospheric CO{sub 2} concentrations by sequestering C in soils.« less

Measurement error in the Liebowitz Social Anxiety Scale: results from a general adult population in Japan.

PubMed

Takada, Koki; Takahashi, Kana; Hirao, Kazuki

2018-01-17

Although the self-report version of Liebowitz Social Anxiety Scale (LSAS) is frequently used to measure social anxiety, data is lacking on the smallest detectable change (SDC), an important index of measurement error. We therefore aimed to determine the SDC of LSAS. Japanese adults aged 20-69 years were invited from a panel managed by a nationwide internet research agency. We then conducted a test-retest internet survey with a two-week interval to estimate the SDC at the individual (SDC ind ) and group (SDC group ) levels. The analysis included 1300 participants. The SDC ind and SDC group for the total fear subscale (scoring range: 0-72) were 23.52 points (32.7%) and 0.65 points (0.9%), respectively. The SDC ind and SDC group for the total avoidance subscale (scoring range: 0-72) were 32.43 points (45.0%) and 0.90 points (1.2%), respectively. The SDC ind and SDC group for the overall total score (scoring range: 0-144) were 45.90 points (31.9%) and 1.27 points (0.9%), respectively. Measurement error is large and indicate the potential for major problems when attempting to use the LSAS to detect changes at the individual level. These results should be considered when using the LSAS as measures of treatment change.

A Commercial Architecture for Satellite Imagery

DTIC Science & Technology

2006-09-01

incorporates image detection from the visible and near - infrared wavelengths, 3) 16 Ball Aerospace...present limited total area coverage since the field of regard is smallest. The opposite is true for resolution and total area coverage near apogee. The...27 B. SENSOR FIELD OF REGARD ...................................................................27 1. Spherical Analysis

40 CFR 92.102 - Definitions and abbreviations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.102...), also apply: Accuracy means the difference between the measured value and the true value, where the true... otherwise. Readability means the smallest difference in measured values that can be detected. For example...

40 CFR 92.102 - Definitions and abbreviations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.102...), also apply: Accuracy means the difference between the measured value and the true value, where the true... otherwise. Readability means the smallest difference in measured values that can be detected. For example...

40 CFR 92.102 - Definitions and abbreviations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.102...), also apply: Accuracy means the difference between the measured value and the true value, where the true... otherwise. Readability means the smallest difference in measured values that can be detected. For example...

40 CFR 92.102 - Definitions and abbreviations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) CONTROL OF AIR POLLUTION FROM LOCOMOTIVES AND LOCOMOTIVE ENGINES Test Procedures § 92.102...), also apply: Accuracy means the difference between the measured value and the true value, where the true... otherwise. Readability means the smallest difference in measured values that can be detected. For example...

Application of Diffusion Tensor Imaging Parameters to Detect Change in Longitudinal Studies in Cerebral Small Vessel Disease.

PubMed

Zeestraten, Eva Anna; Benjamin, Philip; Lambert, Christian; Lawrence, Andrew John; Williams, Owen Alan; Morris, Robin Guy; Barrick, Thomas Richard; Markus, Hugh Stephen

2016-01-01

Cerebral small vessel disease (SVD) is the major cause of vascular cognitive impairment, resulting in significant disability and reduced quality of life. Cognitive tests have been shown to be insensitive to change in longitudinal studies and, therefore, sensitive surrogate markers are needed to monitor disease progression and assess treatment effects in clinical trials. Diffusion tensor imaging (DTI) is thought to offer great potential in this regard. Sensitivity of the various parameters that can be derived from DTI is however unknown. We aimed to evaluate the differential sensitivity of DTI markers to detect SVD progression, and to estimate sample sizes required to assess therapeutic interventions aimed at halting decline based on DTI data. We investigated 99 patients with symptomatic SVD, defined as clinical lacunar syndrome with MRI confirmation of a corresponding infarct as well as confluent white matter hyperintensities over a 3 year follow-up period. We evaluated change in DTI histogram parameters using linear mixed effect models and calculated sample size estimates. Over a three-year follow-up period we observed a decline in fractional anisotropy and increase in diffusivity in white matter tissue and most parameters changed significantly. Mean diffusivity peak height was the most sensitive marker for SVD progression as it had the smallest sample size estimate. This suggests disease progression can be monitored sensitively using DTI histogram analysis and confirms DTI's potential as surrogate marker for SVD.

Ultrasound sensitivity to changes in gout: a longitudinal study after two years of treatment.

PubMed

Peiteado, Diana; Villalba, Alejandro; Martín-Mola, Emilio; Balsa, Alejandro; De Miguel, Eugenio

2017-01-01

The goals of our study are to evaluate the urate-lowering therapy (ULT) effect on gout ultrasound (US) lesions and to explore US sensitivity to change in gout patients. Patients with chronic and symptomatic gout, confirmed by crystal identification, were prospectively included. Clinical and US assessments were performed at baseline and after 6, 12 and 24 months of ULT. The presence of double contour sign (DCS) and US- detectable tophi were assessed in the first metatarsophalangeals, the knees and patellar tendons. The mean and standard deviation were calculated for each parameter. The correlation between the clinical and US parameters was assessed by calculating Pearson's correlation coefficient. Sensitivity to change in the US examinations was assessed by estimating the smallest detectable difference (SDD). Twenty-three consecutive patients were included (96% men; mean age 59 ± 11 years). DCS and US tophi were detected in 73.9% and 91.3% of patients at baseline. A significant parallel improvement in the serum urate, clinical parameters and US lesions was found at the follow-up assessment. The SDD values for the global DCS and tophi were 0.52 and 0.69, respectively, which were smaller than the differences achieved over the course of the two years. A significant correlation between DCS and clinical parameters was observed (r =0.49, p=0.038). Ultrasound findings in gout patients show sensitivity to change and concurrent validity with uric acid reduction after ULT in gout patients. US can be a useful tool for gout tophus burden monitoring.

Dual-window dual-bandwidth spectroscopic optical coherence tomography metric for qualitative scatterer size differentiation in tissues.

PubMed

Tay, Benjamin Chia-Meng; Chow, Tzu-Hao; Ng, Beng-Koon; Loh, Thomas Kwok-Seng

2012-09-01

This study investigates the autocorrelation bandwidths of dual-window (DW) optical coherence tomography (OCT) k-space scattering profile of different-sized microspheres and their correlation to scatterer size. A dual-bandwidth spectroscopic metric defined as the ratio of the 10% to 90% autocorrelation bandwidths is found to change monotonically with microsphere size and gives the best contrast enhancement for scatterer size differentiation in the resulting spectroscopic image. A simulation model supports the experimental results and revealed a tradeoff between the smallest detectable scatterer size and the maximum scatterer size in the linear range of the dual-window dual-bandwidth (DWDB) metric, which depends on the choice of the light source optical bandwidth. Spectroscopic OCT (SOCT) images of microspheres and tonsil tissue samples based on the proposed DWDB metric showed clear differentiation between different-sized scatterers as compared to those derived from conventional short-time Fourier transform metrics. The DWDB metric significantly improves the contrast in SOCT imaging and can aid the visualization and identification of dissimilar scatterer size in a sample. Potential applications include the early detection of cell nuclear changes in tissue carcinogenesis, the monitoring of healing tendons, and cell proliferation in tissue scaffolds.

Leading Schools through Major Change

ERIC Educational Resources Information Center

Syed, Sarosh

2013-01-01

Changing even the smallest things in schools is hard--just ask any principal who has overseen a rescheduling of bus routes. So imagine the difficulty of getting a school to move its curriculum and instruction from familiar learning requirements to brand-new nationwide standards. Yet this is exactly the sort of change public schools in 45 states…

The Nature of Evolution

ERIC Educational Resources Information Center

Alles, David L.

2005-01-01

The nature of evolution, the historical change in the universe, and the change that is caused by the workings of the dynamic processes at the smallest and largest scales are studied. It is viewed that the cumulative change in the historical systems is caused by evolution, which is a type of causal relationship and evolutionary processes could be…

Development of a Free-Swimming Acoustic Tool for Liquid Pipeline Leak Detection Including Evaluation for Natural Gas Pipeline Applications

DOT National Transportation Integrated Search

2010-08-01

Significant financial and environmental consequences often result from line leakage of oil product pipelines. Product can escape into the surrounding soil as even the smallest leak can lead to rupture of the pipeline. From a health perspective, water...

A PDMS microfiber Mach-Zehnder interferometer and determination of nanometer displacements

NASA Astrophysics Data System (ADS)

Martincek, Ivan; Kacik, Daniel

2018-01-01

A polydimethylsiloxane (PDMS) microfiber Mach-Zehnder interferometer (MZI), integrated between single-mode optical fibers (SMFs), is proposed and demonstrated experimentally. One arm of the interferometer consists of a microfiber of diameter 7 μm and length 270 μm; the second is an air arm. Due to the good elastic properties of PDMS microfiber, the length of the air arm of MZI can be changed by changing the distance between SMFs. The change in length of the air arm results in a change in the transmission characteristics of the MZI; thus, the relative displacement can be measured in the range 10-250 nm. By measuring the peak-to-peak amplitude of the difference in transmission powers (in dB), the smallest displacement by prepared MZI was determined as being on the order of a few nm for a ratio of intensities of 0.135. For a higher ratio of intensities of transmission functions, the smallest displacement could be determined on the order of subnanometers.

Cytological detection of a peripheral lung carcinoma in a coke oven worker

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

Teplitz, R.L.; Belman, M.J.; Nathwani, B.

1980-06-01

OSHA mandated programs of pulmonary cytology among coke oven workers have resulted in detection of a number of unsuspected tumors. While it is too early to determine the eventual impact of these programs, this report describes the detection of a 0.3 cm peripheral lesion, believed to be the smallest identified by cytology. In addition to being diminutive, the tumor proved to be of the epidermoid type, unusual for the location. Further investigation is required to determine whether peripheral epidermoid neoplasms are associated with exposure to coke vapors.

Psychometric viability of measures of functional performance commonly used for people with dementia: a systematic review of measurement properties.

PubMed

Fox, Benjamin; Henwood, Timothy; Keogh, Justin; Neville, Christine

2016-08-01

Confidence in findings can only be drawn from measurement tools that have sound psychometric properties for the population with which they are used. Within a dementia specific population, measures of physical function have been poorly justified in exercise intervention studies, with justification of measures based on validity or reliability studies from dissimilar clinical populations, such as people with bronchitis or healthy older adults without dementia. To review the reliability and validity of quantitative measures of pre-identified physical function, as commonly used within exercise intervention literature for adults with dementia. Participants were adults, aged 65 years and older, with a confirmed medical diagnosis of dementia. n/a Desired studies were observational and cross-sectional and that assessed measures from a pre-identified list of measures of physical function. Studies that assessed the psychometric constructs of reliability and validity were targeted. COSMIN taxology was used to define reliability and validity. This included, but were not limited to, Intra-Class Correlations, Kappa, Cronbach's Alpha, Chi Squared, Standard Error of Measurement, Minimal Detectable Change and Limits of Agreement. Published material was sourced from the following four databases: MEDLINE, EMBASE, CINAHL and ISI Web of Science. Grey literature was searched for using ALOIS, Google Scholar and ProQuest. The COSMIN checklist was used to assess methodological quality of included studies. Assessment was completed by two reviewers independently. Reliability and validity data was extracted from included studies using standardized Joanna Briggs Institute data collection forms. Extraction was completed by two reviewers. A narrative synthesis of measurement properties of the tools used to measure physical function was performed. Quantitative meta-analysis was conducted for Intra-Class Correlation Coefficients only. With respect to relative reliability, studies reporting assessed measures had intraclass correlation coefficients greater than 0.71, indicating their suitability for use at a group level. However, a consistent finding among studies that included assessment of absolute reliability was that intra individual variation was too large for meaningful measurement of individuals. This was indicated by large Minimal Detectable Change (MDC) scores. Walk Speed has the smallest reported Mimimal Detectable Change score at 0.11m/s. This represented a change of 35% before statistical variation could be eliminated as the cause for this change. All measures had large MDC values. Walk Speed had the smallest MDC values at 0.11m/s, which represented a necessary change of 35%. Only a limited number of studies assessed the validity of measures. This supports the use of these measures in a very narrow selection of circumstances (see Summary of Findings). In summary, measures have shown appropriate levels of relative reliability. This supports their use at the group level. However, large levels of intra-individual variation undermine their applicability at the individual level. Limited studies of validity were available to this review, which limits a conclusion on whether measures are valid for people with dementia.

Detecting Earth's temporarily-captured natural satellites-Minimoons

NASA Astrophysics Data System (ADS)

Bolin, Bryce; Jedicke, Robert; Granvik, Mikael; Brown, Peter; Howell, Ellen; Nolan, Michael C.; Jenniskens, Peter; Chyba, Monique; Patterson, Geoff; Wainscoat, Richard

2014-10-01

We present a study on the discoverability of temporarily captured orbiters (TCOs) by present day or near-term anticipated ground-based and space-based facilities. TCOs (Granvik, M., Vaubaillon, J., Jedicke, R. [2012]. Icarus 218, 262-277) are potential targets for spacecraft rendezvous or human exploration (Chyba, M., Patterson, G., Picot, G., Granvik, M., Jedicke, R., Vaubaillon, J. [2014]. J. Indust. Manage. Optim. 10, 477-501) and provide an opportunity to study the population of the smallest asteroids in the Solar System. We find that present day ground-based optical surveys such as Pan-STARRS and ATLAS can discover the largest TCOs over years of operation. A targeted survey conducted with the Subaru telescope can discover TCOs in the 0.5-1.0 m diameter size range in about 5 nights of observing. Furthermore, we discuss the application of space-based infrared surveys, such as NEOWISE, and ground-based meteor detection systems such as CAMS, CAMO and ASGARD in discovering TCOs. These systems can detect TCOs but at a uninteresting rate. Finally, we discuss the application of bi-static radar at Arecibo and Green Bank to discover TCOs. Our radar simulations are strongly dependent on the rotation rate distribution of the smallest asteroids but with an optimistic distribution we find that these systems have >80% chance of detecting a >10 cm diameter TCO in about 40 h of operation.

Analysis and modeling of daily air pollutants in the city of Ruse, Bulgaria

NASA Astrophysics Data System (ADS)

Zheleva, I.; Veleva, E.; Filipova, M.

2017-10-01

The city of Ruse is situated in the north-eastern part of Bulgaria. The northern boundary of Ruse region goes along the Danube river valley and coincides with the state boundary of the Republic of Bulgaria and the Republic of Romania. The climate of the region of Ruse is temperate continental, characterized by cold winters and dry, warm summers. Spring and autumn are short. In our previous work we studied information from 40 years period measurements [6] of temperature, air humidity and atmospheric pressure in Ruse region, Bulgaria. It was shown that mean values of the temperature in Ruse region are slightly goes up for the last 10 years and they are bigger than the mean temperature for Bulgaria. This could be a proof for climate change in Ruse region of Bulgaria. The most variable atmospheric parameter is air humidity during the spring seasons. The hardest change of temperature and atmospheric pressure is during January. Temperature has biggest change in January and smallest - in July. Humidity has biggest change in April and smallest - in October. Atmospheric pressure has biggest change in January and smallest - in July [5]. Air pollution maybe affects temperature, atmospheric pressure and humidity. All this in our opinion may be a reason for the increase in average temperatures for the period examined. This paper is devoted to examine air pollution in the Ruse region. It presents a statistical analysis of the level of air pollution in Ruse on data from the monitoring stations in the city. The measurements cover the period from 2015 including up to now. For the most dangerous pollutant PM10 we create an ARIMA model which is in a good agreement with the PM10 measurements.

The American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale; translation and validation of the Dutch language version for ankle fractures.

PubMed

de Boer, A Siebe; Tjioe, Roderik J C; Van der Sijde, Fleur; Meuffels, Duncan E; den Hoed, Pieter T; Van der Vlies, Cornelis H; Tuinebreijer, Wim E; Verhofstad, Michael H J; Van Lieshout, Esther M M

2017-08-03

The American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale is among the most commonly used instruments for measuring outcome of treatment in patients who sustained a complex ankle or hindfoot injury. It consists of a patient-reported and a physician-reported part. A validated, Dutch version of this instrument is currently not available. The aim of this study was to translate the instrument into Dutch and to determine the measurement properties of the AOFAS Ankle-Hindfoot Scale Dutch language version (DLV) in patients with a unilateral ankle fracture. Multicentre (two Dutch hospitals), prospective observational study. In total, 142 patients with a unilateral ankle fracture were included. Ten patients were lost to follow-up. Patients completed the subjective (patient-reported) part of the AOFAS Ankle-Hindfoot Scale-DLV. A physician or trained physician-assistant completed the physician-reported part. For comparison and evaluation of the measuring characteristics, the Foot Function Index and the Short Form-36 were completed by the patient. Descriptive statistics (including floor and ceiling effects), reliability (ie, internal consistency), construct validity, reproducibility (ie, test-retest reliability, agreement and smallest detectable change) and responsiveness were determined. The AOFAS-DLV and its subscales showed good internal consistency (Cronbach's α >0.90). Construct validity and longitudinal validity were proven to be adequate (76.5% of predefined hypotheses were confirmed). Floor effects were not present. Ceiling effects were present from 6 months onwards, as expected. Responsiveness was adequate, with a smallest detectable change of 12.0 points. The AOFAS-DLV is a reliable, valid and responsive measurement instrument for evaluating functional outcome in patients with a unilateral ankle fracture. This implies that the questionnaire is suitable to compare different treatment modalities within this population or to compare outcome across hospitals. The Netherlands Trial Register (NTR5613; 05-jan-2016). © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Wheelchair Shuttle Test for Assessing Aerobic Fitness in Youth With Spina Bifida: Validity and Reliability

PubMed Central

de Groot, Janke F.; Backx, Frank J.G.; Benner, Joyce; Kruitwagen, Cas L.J.J.; Takken, Tim

2017-01-01

Abstract Background Testing aerobic fitness in youth is important because of expected relationships with health. Objective The purpose of the study was to estimate the validity and reliability of the Shuttle Ride Test in youth who have spina bifida and use a wheelchair for mobility and sport. Design Ths study is a validity and reliability study. Methods The Shuttle Ride Test, Graded Wheelchair Propulsion Test, and skill-related fitness tests were administered to 33 participants for the validity study (age = 14.5 ± 3.1 y) and to 28 participants for the reliability study (age = 14.7 ± 3.3 y). Results No significant differences were found between the Graded Wheelchair Propulsion Test and the Shuttle Ride Test for most cardiorespiratory responses. Correlations between the Graded Wheelchair Propulsion Test and the Shuttle Ride Test were moderate to high (r = .55–.97). The variance in peak oxygen uptake (VO2peak) could be predicted for 77% of the participants by height, number of shuttles completed, and weight, with large prediction intervals. High correlations were found between number of shuttles completed and skill-related fitness tests (CI = .73 to −.92). Intraclass correlation coefficients were high (.77–.98), with a smallest detectable change of 1.5 for number of shuttles completed and with coefficients of variation of 6.2% and 6.4% for absolute VO2peak and relative VO2peak, respectively. Conclusions When measuring VO2peak directly by using a mobile gas analysis system, the Shuttle Ride Test is highly valid for testing VO2peak in youth who have spina bifida and use a wheelchair for mobility and sport. The outcome measure of number of shuttles represents aerobic fitness and is also highly correlated with both anaerobic performance and agility. It is not possible to predict VO2peak accurately by using the number of shuttles completed. Moreover, the Shuttle Ride Test is highly reliable in youth with spina bifida, with a good smallest detectable change for the number of shuttles completed. PMID:29029556

Detection and analysis of high-temperature events in the BIRD mission

NASA Astrophysics Data System (ADS)

Zhukov, Boris; Briess, Klaus; Lorenz, Eckehard; Oertel, Dieter; Skrbek, Wolfgang

2005-01-01

The primary mission objective of a new small Bi-spectral InfraRed Detection (BIRD) satellite is detection and quantitative analysis of high-temperature events like fires and volcanoes. An absence of saturation in the BIRD infrared channels makes it possible to improve false alarm rejection as well as to retrieve quantitative characteristics of hot targets, including their effective fire temperature, area and the radiative energy release. Examples are given of detection and analysis of wild and coal seam fires, of volcanic activity as well as of oil fires in Iraq. The smallest fires detected by BIRD, which were verified on ground, had an area of 12m2 at daytime and 4m2 at night.

Strategies for Analyzing Sub-Micrometer Features with the FE-EPMA

NASA Astrophysics Data System (ADS)

McSwiggen, P.; Armstrong, J. T.; Nielsen, C.

2013-12-01

Changes in column design and electronics, as well as new types of spectrometers and analyzing crystals, have significantly advanced electron microprobes, in terms of stability, reproducibility and detection limits. A major advance in spatial resolution has occurred through the use of the field emission electron gun. The spatial resolution of an analysis is controlled by the diameter of the electron beam and the amount of scatter that takes place within the sample. The beam diameter is controlled by the column and type of electron gun being used. The accelerating voltage and the average atomic number/density of the sample control the amount of electron scatter within the sample. However a large electron interaction volume does not necessarily mean a large analytical volume. The beam electrons may spread out within a large volume, but if the electrons lack sufficient energy to produce the X-ray of interest, the analytical volume could be significantly smaller. Therefore there are two competing strategies for creating the smallest analytical volumes. The first strategy is to reduce the accelerating voltage to produce the smallest electron interaction volume. This low kV analytical approach is ultimately limited by the size of the electron beam itself. With a field emission gun, normally the smallest analytical area is achieved at around 5-7 kV. At lower accelerating voltages, the increase in the beam diameter begins to overshadow the reduction in internal scattering. For tungsten filament guns, the smallest analytical volume is reached at higher accelerating voltages. The second strategy is to minimize the overvoltage during the analysis. If the accelerating voltage is only 1-3 kV greater than the critical ionization energy for the X-ray line of interest, then even if the overall electron interaction volume is large, those electrons quickly loose sufficient energy to produce the desired X-rays. The portion of the interaction volume in which the desired X-rays will be produce will be very small and very near the surface. Both strategies have advantages and disadvantages depending on the ultimate goal of the analysis and the elements involved. This work will examine a number of considerations when attempting to decide which approach is best for a given analytical situation. These include: (1) the size of the analytical volumes, (2) minimum detection limits, (3) quality of the matrix corrections, (4) secondary fluorescence, (5) effects of surface contamination, oxide layers, and carbon coatings. This work is based on results largely from the Fe-Ni binary. A simple conclusion cannot be draw as to which strategy is better overall. The determination is highly system dependent. For many mineral systems, both strategies used in combination will produce the best results. Using multiple accelerating voltages to preform a single analysis allows the analyst to optimize their analytical conditions for each element individually.

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

Ballermann, B.J.

To enable serial measurements of plasma atrial natriuretic peptide (ANP) concentrations in the rat, a microradioreceptor assay (RRA) for this hormone was developed. Glomerular microsomes bearing ANP receptors were used to bind ANP. The smallest quantity of ANP detectable by this method was 0.2 fmol/sample. By contrast, a radioimmunoassay for ANP was sensitive to 2.4 fmol/sample. The intra- and interassay coefficients of variation for the RRA were 4.1 and 11.6%, respectively. Recovery of 10, 20, 50, and 100 pM synthetic ANP added to unextracted rat plasma was essentially 100%. Biologically inactive, synthetic amino- and carboxy-terminal ANP fragments added to ratmore » plasma were not detected. Plasma ANP was stable when measured four consecutive times at 90-min intervals in 10 fasting rats. In a separate group of rats, fasting plasma ANP levels averaged 34 {plus minus} 3 and rose to 57 {plus minus} 5 pM in the postprandial state, whereas levels in fasting time controls remained constant. It is concluded that the RRA for ANP described here detects ANP in microliter quantities of unextracted rat plasma. Thus serial measurements of ANP concentrations can be undertaken in rats without inducing major changes in the volume status.« less

Application of Diffusion Tensor Imaging Parameters to Detect Change in Longitudinal Studies in Cerebral Small Vessel Disease

PubMed Central

Zeestraten, Eva Anna; Benjamin, Philip; Lambert, Christian; Lawrence, Andrew John; Williams, Owen Alan; Morris, Robin Guy; Barrick, Thomas Richard; Markus, Hugh Stephen

2016-01-01

Cerebral small vessel disease (SVD) is the major cause of vascular cognitive impairment, resulting in significant disability and reduced quality of life. Cognitive tests have been shown to be insensitive to change in longitudinal studies and, therefore, sensitive surrogate markers are needed to monitor disease progression and assess treatment effects in clinical trials. Diffusion tensor imaging (DTI) is thought to offer great potential in this regard. Sensitivity of the various parameters that can be derived from DTI is however unknown. We aimed to evaluate the differential sensitivity of DTI markers to detect SVD progression, and to estimate sample sizes required to assess therapeutic interventions aimed at halting decline based on DTI data. We investigated 99 patients with symptomatic SVD, defined as clinical lacunar syndrome with MRI confirmation of a corresponding infarct as well as confluent white matter hyperintensities over a 3 year follow-up period. We evaluated change in DTI histogram parameters using linear mixed effect models and calculated sample size estimates. Over a three-year follow-up period we observed a decline in fractional anisotropy and increase in diffusivity in white matter tissue and most parameters changed significantly. Mean diffusivity peak height was the most sensitive marker for SVD progression as it had the smallest sample size estimate. This suggests disease progression can be monitored sensitively using DTI histogram analysis and confirms DTI’s potential as surrogate marker for SVD. PMID:26808982

Responsiveness, Sensitivity, and Minimally Detectable Difference of the Graded and Redefined Assessment of Strength, Sensibility, and Prehension, Version 1.0.

PubMed

Kalsi-Ryan, Sukhvinder; Beaton, Dorcas; Ahn, Henry; Askes, Heather; Drew, Brian; Curt, Armin; Popovic, Milos R; Wang, Justin; Verrier, Mary C; Fehlings, Michael G

2016-02-01

As spinal cord injury (SCI) trials begin to involve subjects with acute cervical SCI, establishing the property of an upper limb outcome measure to detect change over time is critical for its usefulness in clinical trials. The objectives of this study were to define responsiveness, sensitivity, and minimally detectable difference (MDD) of the Graded Redefined Assessment of Strength, Sensibility, and Prehension (GRASSP). An observational, longitudinal study was conducted. International Standards of Neurological Classification of SCI (ISNCSCI), GRASSP, Capabilities of Upper Extremity Questionnaire (CUE-Q), and Spinal Cord Independence Measure (SCIM) were administered 0-10 days, 1, 3, 6, and 12 months post-injury. Standardized Response Means (SRM) for GRASSP and ISNCSCI measures were calculated. Longitudinal construct validity was calculated using Pearson correlation coefficients. Smallest real difference for all subtests was calculated to define the MDD values for all GRASSP subtests. Longitudinal construct validity demonstrated GRASSP and all external measures to be responsive to neurological change for 1 year post-injury. SRM values for the GRASSP subtests ranged from 0.25 to 0.85 units greater than that for ISNCSCI strength and sensation, SCIM-SS, and CUE-Q. MDD values for GRASSP subtests ranged from 2-5 points. GRASSP demonstrates good responsiveness and excellent sensitivity that is superior to ISNCSCI and SCIM III. MDD values are useful in the evaluation of interventions in both clinical and research settings. The responsiveness and sensitivity of GRASSP make it a valuable condition-specific measure in tetraplegia, where changes in upper limb neurological and functional outcomes are essential for evaluating the efficacy of interventions.

Thermal comfort evaluation of three genetic lines of modern pigs using thermal images

USDA-ARS?s Scientific Manuscript database

Previous ARS research found that heat production of growing-finishing swine is 6 – 41% higher than documented in the ASABE and ASHRAE standards. The smallest changes were noted at the lightest weight pigs. This change is most likely due to larger, faster growing genotypes used in modern swine prod...

Reliability of Metrics Associated with a Counter-Movement Jump Performed on a Force Plate

ERIC Educational Resources Information Center

Lombard, Wayne; Reid, Sorrel; Pearson, Keagan; Lambert, Michael

2017-01-01

The counter-movement jump is a consequence of maximal force, rate of force developed, and neuromuscular coordination. Thus, the counter-movement jump has been used to monitor various training adaptations. However, the smallest detectable difference of counter-movement jump metrics has yet to be established. The objective of the present study was…

Parallel electric fields detected via conjugate electron echoes during the Echo 7 sounding rocket flight

NASA Technical Reports Server (NTRS)

Nemzek, R. J.; Winckler, J. R.

1991-01-01

Electron detectors on the Echo 7 active sounding rocket experiment measured 'conjugate echoes' resulting from artificial electron beam injections. Analysis of the drift motion of the electrons after a complete bounce leads to measurements of the magnetospheric convection electric field mapped to ionospheric altitudes. The magnetospheric field was highly variable, changing by tens of mV/m on time scales of as little as hundreds of millisec. While the smallest-scale magnetospheric field irregularities were mapped out by ionospheric conductivity, larger-scale features were enhanced by up to 50 mV/m in the ionosphere. The mismatch between magnetospheric and ionspheric convection fields indicates a violation of the equipotential field line condition. The parallel fields occurred in regions roughly 10 km across and probably supported a total potential drop of 10-100 V.

Topology of Neutral Hydrogen within the Small Magellanic Cloud

NASA Astrophysics Data System (ADS)

Chepurnov, A.; Gordon, J.; Lazarian, A.; Stanimirovic, S.

2008-12-01

In this paper, genus statistics have been applied to an H I column density map of the Small Magellanic Cloud in order to study its topology. To learn how topology changes with the scale of the system, we provide topology studies for column density maps at varying resolutions. To evaluate the statistical error of the genus, we randomly reassign the phases of the Fourier modes while keeping the amplitudes. We find that at the smallest scales studied (40 pc <= λ <= 80 pc), the genus shift is negative in all regions, implying a clump topology. At the larger scales (110 pc <= λ <= 250 pc), the topology shift is detected to be negative (a "meatball" topology) in four cases and positive (a "swiss cheese" topology) in two cases. In four regions, there is no statistically significant topology shift at large scales.

Asteroid Properties from Photometric Observations: Constraining Non-Gravitational Processes in Asteroids

NASA Astrophysics Data System (ADS)

Pravec, P.

2013-05-01

From October 2012 we run our NEOSource project on the Danish 1.54-m telescope on La Silla. The primary aim of the project is to study non-gravitational processes in asteroids near the Earth and in their source regions in the main asteroidal belt. In my talk, I will give a brief overview of our current knowledge of the asteroidal non- gravitational processes and how we study them with photometric observations. I will talk especially about binary and paired asteroids that appear to be formed by rotational fission, about detecting the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) and BYORP (binary YORP) effects of anisotropic thermal emission from asteroids that change their spins and satellite orbits, and about non-principal axis rotators (the so called "tumblers") among the smallest, super-critically rotating asteroids with sizes < 100 meters.

Using NDVI to assess vegetative land cover change in central Puget Sound.

PubMed

Morawitz, Dana F; Blewett, Tina M; Cohen, Alex; Alberti, Marina

2006-03-01

We used the Normalized Difference Vegetation Index (NDVI) in the rapidly growing Puget Sound region over three 5-year time blocks between 1986-1999 at three spatial scales in 42 Watershed Administrative Units (WAUs) to assess changes in the amounts and patterns of green vegetation. On average, approximately 20% of the area in each WAU experienced significant NDVI change over each 5-year time block. Cumulative NDVI change over 15 years (summing change over each 5-year time block) was an average of approximately 60% of each WAU, but was as high as 100% in some. At the regional scale, seasonal weather patterns and green-up from logging were the primary drivers of observed increases in NDVI values. At the WAU scale, anthropogenic factors were important drivers of both positive and negative NDVI change. For example, population density was highly correlated with negative NDVI change over 15 years (r = 0.66, P < 0.01), as was road density (r = 0.71, P < 0.01). At the smallest scale (within 3 case study WAUs) land use differences such as preserving versus harvesting forest lands drove vegetation change. We conclude that large areas within most watersheds are continually and heavily impacted by the high levels of human use and development over short time periods. Our results indicate that varying patterns and processes can be detected at multiple scales using changes in NDVIa values.

Development of an adaptive failure detection and identification system for detecting aircraft control element failures

NASA Technical Reports Server (NTRS)

Bundick, W. Thomas

1990-01-01

A methodology for designing a failure detection and identification (FDI) system to detect and isolate control element failures in aircraft control systems is reviewed. An FDI system design for a modified B-737 aircraft resulting from this methodology is also reviewed, and the results of evaluating this system via simulation are presented. The FDI system performed well in a no-turbulence environment, but it experienced an unacceptable number of false alarms in atmospheric turbulence. An adaptive FDI system, which adjusts thresholds and other system parameters based on the estimated turbulence level, was developed and evaluated. The adaptive system performed well over all turbulence levels simulated, reliably detecting all but the smallest magnitude partially-missing-surface failures.

Validity and sensitivity to change of the semi-quantitative OMERACT ultrasound scoring system for tenosynovitis in patients with rheumatoid arthritis.

PubMed

Ammitzbøll-Danielsen, Mads; Østergaard, Mikkel; Naredo, Esperanza; Terslev, Lene

2016-12-01

The aim was to evaluate the metric properties of the semi-quantitative OMERACT US scoring system vs a novel quantitative US scoring system for tenosynovitis, by testing its intra- and inter-reader reliability, sensitivity to change and comparison with clinical tenosynovitis scoring in a 6-month follow-up study. US and clinical assessments of the tendon sheaths of the clinically most affected hand and foot were performed at baseline, 3 and 6 months in 51 patients with RA. Tenosynovitis was assessed using the semi-quantitative scoring system (0-3) proposed by the OMERACT US group and a new quantitative US evaluation (0-100). A sum for US grey scale (GS), colour Doppler (CD) and pixel index (PI), respectively, was calculated for each patient. In 20 patients, intra- and inter-observer agreement was established between two independent investigators. A binary clinical tenosynovitis score was performed, calculating a sum score per patient. The intra- and inter-observer agreements for US tenosynovitis assessments were very good at baseline and for change for GS and CD, but less good for PI. The smallest detectable change was 0.97 for GS, 0.93 for CD and 30.1 for PI. The sensitivity to change from month 0 to 6 was high for GS and CD, and slightly higher than for clinical tenosynovitis score and PI. This study demonstrated an excellent intra- and inter-reader agreement between two investigators for the OMERACT US scoring system for tenosynovitis and a high ability to detect changes over time. Quantitative assessment by PI did not add further information. © The Author 2016. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Algorithmic Approaches for Place Recognition in Featureless, Walled Environments

DTIC Science & Technology

2015-01-01

inertial measurement unit LIDAR light detection and ranging RANSAC random sample consensus SLAM simultaneous localization and mapping SUSAN smallest...algorithm 38 21 Typical input image for general junction based algorithm 39 22 Short exposure image of hallway junction taken by LIDAR 40 23...discipline of simultaneous localization and mapping ( SLAM ) has been studied intensively over the past several years. Many technical approaches

Some lemma on spectrum of eigen value regarding power method

NASA Astrophysics Data System (ADS)

Jamali, A. R. M. Jalal Uddin; Alam, Md. Sah

2017-04-01

Eigen value problems arise in almost all science and engineering fields. There exist some smart methods in literature in which most of them are able to find only Eigen values but could not find corresponding Eigen vectors. There exist many engineering as well as scientific fields in which both largest as well as smallest Eigen pairs are required. Power method is very simple but a powerful tool for finding largest Eigen value and corresponding Eigen vector (Eigen-pair). Again Inverse Power method is applied to find out smallest Eigen-pair and/or desire Eigen-pairs. But it is known that Inverse Power method is computationally very costly. On the other hand by using shifting property, Power method can find further Eigen-pairs. But the position of this Eigen value in the set of spectrum of the Eigen values is not identified. In this regard we proposed four lemma associate with Modified Power method. Each Lemma is proved ornately. The Modified Power method is implemented and illustrates an example for the verification of the Lemma. By using lemma the modified power algorithm is able to find out both largest and smallest Eigen-pairs successfully and efficiently in some cases. Moreover by the help of the Lemma, algorithm is able to detect the nature (positive and negative) of the Eigen values.

Response of vegetation and breeding birds to the removal of cattle on the San Pedro River, Arizona (U.S.A.)

USGS Publications Warehouse

Krueper, D.; Bart, Jonathan; Rich, T.

2003-01-01

In late 1987 cattle were removed from the San Pedro Riparian National Conservation Area ( NCA ) in southeastern Arizona ( U.S.A. ). We monitored vegetation density and abundance of birds during the breeding season during 1986a??1990 in riparian, mesquite grassland, and Chihuahuan desert-scrub communities in the NCA. The density of herbaceous vegetation increased four- to six-fold in riparian and mesquite grassland communities. Little change occurred in herbaceous vegetation in desert scrub, or in the density of shrubs or trees in any of the communities. Of 61 bird species for which sufficient data were collected, mean detections per kilometer increased for 42 species, 26 significantly, and decreased for 19 species, 8 significantly. The number of individuals of all avian species detected on surveys increased each year from 103/kilometer in 1986 to 221/kilometer in 1991, an average annual increase of 23% ( p < 0.001 ). The largest increases occurred in riparian species, open-cup nesters, Neotropical migrants, and insectivores. Species of the Chihuahuan desert-scrub, in which vegetation changed the least, showed the smallest increases. Only a few of the species showed increasing regional trends for the same period, as demonstrated by the North American Breeding Bird Survey; thus, increases on the San Pedro Riparian NCA were likely caused by the change in local conditions, not by regional effects. Our results suggest that removing cattle from riparian areas in the southwestern United States can have profound benefits for breeding birds.

Agile lensing-based non-contact liquid level optical sensor for extreme environments

NASA Astrophysics Data System (ADS)

Reza, Syed Azer; Riza, Nabeel A.

2010-09-01

To the best of the author's knowledge, demonstrated is the first opto-fluidic technology- based sensor for detection of liquid levels. An opto-fluidic Electronically Controlled Variable Focus Lens (ECVFL) is used to change the spatial intensity profile of the low power optical beam falling on the liquid surface. By observing, tuning and measuring the liquid surface reflected intensity profile to reach its smallest size, the liquid level is determined through a beam spot size versus ECVFL focal length calibration table. Using a 50 μW 632.8 nm laser wavelength liquid illuminating beam, a proof-of-concept sensor is tested using engine oil, vegetable oil, and detergent fluid with measured liquid levels over a 75 cm range. This non-contact Radio Frequency (RF) modulation-free sensor is particularly suited for hazardous fluids in window-accessed sealed containers including liquid carrying vessels in Electromagnetic Interference (EMI) rich environments.

Reliability and Validity of a New Test of Change-of-Direction Speed for Field-Based Sports: the Change-of-Direction and Acceleration Test (CODAT).

PubMed

Lockie, Robert G; Schultz, Adrian B; Callaghan, Samuel J; Jeffriess, Matthew D; Berry, Simon P

2013-01-01

Field sport coaches must use reliable and valid tests to assess change-of-direction speed in their athletes. Few tests feature linear sprinting with acute change- of-direction maneuvers. The Change-of-Direction and Acceleration Test (CODAT) was designed to assess field sport change-of-direction speed, and includes a linear 5-meter (m) sprint, 45° and 90° cuts, 3- m sprints to the left and right, and a linear 10-m sprint. This study analyzed the reliability and validity of this test, through comparisons to 20-m sprint (0-5, 0-10, 0-20 m intervals) and Illinois agility run (IAR) performance. Eighteen Australian footballers (age = 23.83 ± 7.04 yrs; height = 1.79 ± 0.06 m; mass = 85.36 ± 13.21 kg) were recruited. Following familiarization, subjects completed the 20-m sprint, CODAT, and IAR in 2 sessions, 48 hours apart. Intra-class correlation coefficients (ICC) assessed relative reliability. Absolute reliability was analyzed through paired samples t-tests (p ≤ 0.05) determining between-session differences. Typical error (TE), coefficient of variation (CV), and differences between the TE and smallest worthwhile change (SWC), also assessed absolute reliability and test usefulness. For the validity analysis, Pearson's correlations (p ≤ 0.05) analyzed between-test relationships. Results showed no between-session differences for any test (p = 0.19-0.86). CODAT time averaged ~6 s, and the ICC and CV equaled 0.84 and 3.0%, respectively. The homogeneous sample of Australian footballers meant that the CODAT's TE (0.19 s) exceeded the usual 0.2 x standard deviation (SD) SWC (0.10 s). However, the CODAT is capable of detecting moderate performance changes (SWC calculated as 0.5 x SD = 0.25 s). There was a near perfect correlation between the CODAT and IAR (r = 0.92), and very large correlations with the 20-m sprint (r = 0.75-0.76), suggesting that the CODAT was a valid change-of-direction speed test. Due to movement specificity, the CODAT has value for field sport assessment. Key pointsThe change-of-direction and acceleration test (CODAT) was designed specifically for field sport athletes from specific speed research, and data derived from time-motion analyses of sports such as rugby union, soccer, and Australian football. The CODAT features a linear 5-meter (m) sprint, 45° and 90° cuts and 3-m sprints to the left and right, and a linear 10-m sprint.The CODAT was found to be a reliable change-of-direction speed assessment when considering intra-class correlations between two testing sessions, and the coefficient of variation between trials. A homogeneous sample of Australian footballers resulted in absolute reliability limitations when considering differences between the typical error and smallest worthwhile change. However, the CODAT will detect moderate (0.5 times the test's standard deviation) changes in performance.The CODAT correlated with the Illinois agility run, highlighting that it does assess change-of-direction speed. There were also significant relationships with short sprint performance (i.e. 0-5 m and 0-10 m), demonstrating that linear acceleration is assessed within the CODAT, without the extended duration and therefore metabolic limitations of the IAR. Indeed, the average duration of the test (~6 seconds) is field sport-specific. Therefore, the CODAT could be used as an assessment of change-of-direction speed in field sport athletes.

Adaptive Sensor Tuning for Seismic Event Detection in Environment with Electromagnetic Noise

NASA Astrophysics Data System (ADS)

Ziegler, Abra E.

The goal of this research is to detect possible microseismic events at a carbon sequestration site. Data recorded on a continuous downhole microseismic array in the Farnsworth Field, an oil field in Northern Texas that hosts an ongoing carbon capture, utilization, and storage project, were evaluated using machine learning and reinforcement learning techniques to determine their effectiveness at seismic event detection on a dataset with electromagnetic noise. The data were recorded from a passive vertical monitoring array consisting of 16 levels of 3-component 15 Hz geophones installed in the field and continuously recording since January 2014. Electromagnetic and other noise recorded on the array has significantly impacted the utility of the data and it was necessary to characterize and filter the noise in order to attempt event detection. Traditional detection methods using short-term average/long-term average (STA/LTA) algorithms were evaluated and determined to be ineffective because of changing noise levels. To improve the performance of event detection and automatically and dynamically detect seismic events using effective data processing parameters, an adaptive sensor tuning (AST) algorithm developed by Sandia National Laboratories was utilized. AST exploits neuro-dynamic programming (reinforcement learning) trained with historic event data to automatically self-tune and determine optimal detection parameter settings. The key metric that guides the AST algorithm is consistency of each sensor with its nearest neighbors: parameters are automatically adjusted on a per station basis to be more or less sensitive to produce consistent agreement of detections in its neighborhood. The effects that changes in neighborhood configuration have on signal detection were explored, as it was determined that neighborhood-based detections significantly reduce the number of both missed and false detections in ground-truthed data. The performance of the AST algorithm was quantitatively evaluated during a variety of noise conditions and seismic detections were identified using AST and compared to ancillary injection data. During a period of CO2 injection in a nearby well to the monitoring array, 82% of seismic events were accurately detected, 13% of events were missed, and 5% of detections were determined to be false. Additionally, seismic risk was evaluated from the stress field and faulting regime at FWU to determine the likelihood of pressure perturbations to trigger slip on previously mapped faults. Faults oriented NW-SE were identified as requiring the smallest pore pressure changes to trigger slip and faults oriented N-S will also potentially be reactivated although this is less likely.

The Edge Detectors Suitable for Retinal OCT Image Segmentation

PubMed Central

Yang, Jing; Gao, Qian; Zhou, Sheng

2017-01-01

Retinal layer thickness measurement offers important information for reliable diagnosis of retinal diseases and for the evaluation of disease development and medical treatment responses. This task critically depends on the accurate edge detection of the retinal layers in OCT images. Here, we intended to search for the most suitable edge detectors for the retinal OCT image segmentation task. The three most promising edge detection algorithms were identified in the related literature: Canny edge detector, the two-pass method, and the EdgeFlow technique. The quantitative evaluation results show that the two-pass method outperforms consistently the Canny detector and the EdgeFlow technique in delineating the retinal layer boundaries in the OCT images. In addition, the mean localization deviation metrics show that the two-pass method caused the smallest edge shifting problem. These findings suggest that the two-pass method is the best among the three algorithms for detecting retinal layer boundaries. The overall better performance of Canny and two-pass methods over EdgeFlow technique implies that the OCT images contain more intensity gradient information than texture changes along the retinal layer boundaries. The results will guide our future efforts in the quantitative analysis of retinal OCT images for the effective use of OCT technologies in the field of ophthalmology. PMID:29065594

Sizes of the Smallest Particles at the Outer B Ring Edge, Huygens Ringlet, and Strange Ringlet

NASA Astrophysics Data System (ADS)

Eckert, Stephanie; Colwell, Josh E.; Becker, Tracy M.; Esposito, Larry W.

2016-10-01

The Cassini Ultraviolet Imaging Spectrograph (UVIS)'s High Speed Photometer (HSP) has observed stellar occultations of Saturn's rings that reveal ring structure at high resolution. We observe diffraction spikes at the sharp edges of some rings and ringlets where the observed signal exceeds the unocculted star signal, indicating that small particles are diffracting light into the detector. Becker et al. (2015 Icarus doi:10.1016/j.icarus.2015.11.001) analyzed data at the A ring edge and edges of the Encke gap. The smallest particle sizes were a few mm. We use the same technique to analyze the diffraction signal at the outer edge of the B ring and the edges of the so-called Strange ringlet near the outer edge of the Huygens Gap. While we see diffraction from sub-cm particles in the Strange Ringlet, detections from the wider Huygens Ringlet which resides in between the Strange Ringlet and the outer edge of the B ring are weaker and narrower, indicating a cutoff of the size distribution above 1 cm. At the outer edge of the B ring we find strong diffraction signals in 7 of 19 occultations for which the signal and geometry make the detection possible. The typical value of the smallest particle size (amin) is 4 mm and the derived slope of the power-law size distribution (q) is 2.9. The average amin is similar to the 4.5 mm average observed at the A ring outer edge while the q value is lower than the A ring outer edge value of 3.2. In the Strange Ringlet we find strong diffraction signals in 2 of 19 possible occultations for the outer edge and 1 of 17 possible occultations for the inner edge. The smallest particle size is ~5 mm and the derived slope of the power-law size distribution is 3.3. These values are similar to the average values at the A ring outer edge. The absence of a broad diffraction signal at the Huygens Ringlet suggests a different size distribution for that ring than for the Strange Ringlet and the outer several km of the B ring or perhaps less vigorous collisions so that fewer small particles are liberated from the regolith of larger particles.

Survey of Anomaly Detection Methods

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

Ng, B

This survey defines the problem of anomaly detection and provides an overview of existing methods. The methods are categorized into two general classes: generative and discriminative. A generative approach involves building a model that represents the joint distribution of the input features and the output labels of system behavior (e.g., normal or anomalous) then applies the model to formulate a decision rule for detecting anomalies. On the other hand, a discriminative approach aims directly to find the decision rule, with the smallest error rate, that distinguishes between normal and anomalous behavior. For each approach, we will give an overview ofmore » popular techniques and provide references to state-of-the-art applications.« less

Toward an Applied Administrative Science.

ERIC Educational Resources Information Center

Dunbar, Roger L. M.

1983-01-01

A study of 65 articles from the 1981 volumes of "Administrative Science Quarterly" and "Harvard Business Review," using smallest space analysis, found that the few studies adopting subjective (instead of objective) approaches to analyzing organizational change were most likely to provide a basis for an applied administrative…

[A study of sympathetic skin response to the damage of autonomic nerves function in patients with chronic N-hexane poisoning].

PubMed

Situ, Jie; Wu, Jian; Wang, Jing-lin; Zhu, De-xiang; Zhang, Jian-jie; Liu, Wei-wei; Qin, Zhuo-hui

2012-05-01

To study the sympathetic skin response (SSR) to the effects of N-hexane on autonomic nerves function in patients with chronic N-hexane poisoning. The subjects in present study included 30 controls and 37 cases with chronic N-hexane poisoning. Also 37 patients were divided into 3 subgroups (mild, moderate and severe poisoning) according to diagnostic criteria of occupational diseases. All subjects were examined by SSR test and nerve conduction velocity (NCV) test. All patients were reexamined by SSR and NCV every 1 ∼ 2 months. The differences in SSR parameters (latency, amplitude) among groups were observed. In the severe poisoning subgroup, the changes of SSR and NCV parameters (conduction velocity, amplitude) in different poisoning stages were observed. There were significant differences in SSR latency of upper extremity among groups and the significant differences in SSR amplitude of upper and lower extremity among groups (P < 0.05). No significant differences in SSR parameters were found between the adjacent groups (P > 0.05). There were significant differences in SSR latency of upper extremity during different periods and the significant differences in SSR amplitude of upper and lower extremity during different periods among all groups (P < 0.05). The change of SSR parameters consistent with that in NCV. The longest SSR latency of upper extremity and the smallest SSR amplitudes of upper and lower extremity appears 1 - 2 months earlier than that of the smallest action potential amplitude. The damage of autonomic nerves induced by N-hexane increased with poisoning progresses. The damage of autonomic nerves corresponded with the damage of myelin sheath of large myelinated nerves, but which appeared 1 - 2 months earlier than the damage of axon of large myelinated nerves. SSR test may serve as a method to detect the damage of autonomic nerves function in patients with chronic N-hexane poisoning.

Enhancement in the sensitivity of microfluidic enzyme-linked immunosorbent assays through analyte preconcentration.

PubMed

Yanagisawa, Naoki; Dutta, Debashis

2012-08-21

In this Article, we describe a microfluidic enzyme-linked immunosorbent assay (ELISA) method whose sensitivity can be substantially enhanced through preconcentration of the target analyte around a semipermeable membrane. The reported preconcentration has been accomplished in our current work via electrokinetic means allowing a significant increase in the amount of captured analyte relative to nonspecific binding in the trapping/detection zone. Upon introduction of an enzyme substrate into this region, the rate of generation of the ELISA reaction product (resorufin) was observed to increase by over a factor of 200 for the sample and 2 for the corresponding blank compared to similar assays without analyte trapping. Interestingly, in spite of nonuniformities in the amount of captured analyte along the surface of our analysis channel, the measured fluorescence signal in the preconcentration zone increased linearly with time over an enzyme reaction period of 30 min and at a rate that was proportional to the analyte concentration in the bulk sample. In our current study, the reported technique has been shown to reduce the smallest detectable concentration of the tumor marker CA 19-9 and Blue Tongue Viral antibody by over 2 orders of magnitude compared to immunoassays without analyte preconcentration. When compared to microwell based ELISAs, the reported microfluidic approach not only yielded a similar improvement in the smallest detectable analyte concentration but also reduced the sample consumption in the assay by a factor of 20 (5 μL versus 100 μL).

Identifying Acquisition Patterns of Failure Using Systems Archetypes

DTIC Science & Technology

2008-04-02

OF PAGES 18 19a. NAME OF RESPONSIBLE PERSON a. REPORT unclassified b . ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298 (Rev...any but the smallest programs, complete path coverage for defect detection is impractical. Adapted from Pressman , R.S., Software Engineering: A...Firefighting” concept from “Past the Tipping Point” Fix S O B Problem Symptom R “Fixes That Fail” – Systems Archetype S Unintended Consequences S

Strong Scaling and a Scarcity of Small Earthquakes Point to an Important Role for Thermal Runaway in Intermediate-Depth Earthquake Mechanics

NASA Astrophysics Data System (ADS)

Barrett, S. A.; Prieto, G. A.; Beroza, G. C.

2015-12-01

There is strong evidence that metamorphic reactions play a role in enabling the rupture of intermediate-depth earthquakes; however, recent studies of the Bucaramanga Nest at a depth of 135-165 km under Colombia indicate that intermediate-depth seismicity shows low radiation efficiency and strong scaling of stress drop with slip/size, which suggests a dramatic weakening process, as proposed in the thermal shear instability model. Decreasing stress drop with slip and low seismic efficiency could have a measurable effect on the magnitude-frequency distribution of small earthquakes by causing them to become undetectable at substantially larger seismic moment than would be the case if stress drop were constant. We explore the population of small earthquakes in the Bucaramanga Nest using an empirical subspace detector to push the detection limit to lower magnitude. Using this approach, we find ~30,000 small, previously uncatalogued earthquakes during a 6-month period in 2013. We calculate magnitudes for these events using their relative amplitudes. Despite the additional detections, we observe a sharp deviation from a Gutenberg-Richter magnitude frequency distribution with a marked deficiency of events at the smallest magnitudes. This scarcity of small earthquakes is not easily ascribed to the detectability threshold; tests of our ability to recover small-magnitude waveforms of Bucaramanga Nest earthquakes in the continuous data indicate that we should be able to detect events reliably at magnitudes that are nearly a full magnitude unit smaller than the smallest earthquakes we observe. The implication is that nearly 100,000 events expected for a Gutenberg-Richter MFD are "missing," and that this scarcity of small earthquakes may provide new support for the thermal runaway mechanism in intermediate-depth earthquake mechanics.

Effect of opacifiers and UV absorbers on pigmented maxillofacial silicone elastomer, part 1: color stability after artificial aging.

PubMed

Han, Ying; Powers, John M; Kiat-Amnuay, Sudarat

2013-06-01

Much dissatisfaction with the color instability and reduced lifetime of extraoral maxillofacial prostheses due to degradation has been reported. The purpose of this study was to compare the effect of a UV mineral-based light protecting agent (LP) on the color stability of pigmented maxillofacial silicone elastomer MDX-4210/Type A after artificial aging to 2 widely used opacifiers. Forty-five groups were established (n=225 total). Three different types of opacifiers (LP, titanium white dry pigment [TW], or silicone intrinsic white [SW]) were added to silicone MDX-4210/type A at 3 concentrations (5%, 10%, or 15%) and subsequently combined with each of 5 colors (no pigments [control], red, blue, yellow, or mixed pigments). Artists' oil pigment was used with LP and TW, while intrinsic silicone pigment was used to color SW. Before and after an energy exposure of 450 kJ/m(2), CIE L*a*b* values were measured with a spectrophotometer. The CIELAB 50:50% perceptibility (ΔE*=1.1) and acceptability threshold (ΔE*=3.0) were used to interpret color changes (ΔE*). Color differences after aging were subjected to 3-way ANOVA. Means were compared by the Fisher PLSD intervals at α=.05. The ΔE* values of all groups were below the acceptability threshold of ΔE*=3.0, except for the control group of SW at 10%, which showed the greatest color change (ΔE*=3.1). When mixed pigment groups were considered, at 5% concentration, LP showed the smallest color change, followed by SW and TW (P<.05); at 10%, no significant differences among the 3 opacifiers were noted (P>.05); at 15%, LP showed the smallest color change, followed by TW and SW (P<.05). All 3 opacifiers at all concentrations protected pigmented silicone MDX4-4210/Type A from color degradation. The LP group showed the smallest color changes. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Dose and detectability for a cone-beam C-arm CT system revisited

PubMed Central

Ganguly, Arundhuti; Yoon, Sungwon; Fahrig, Rebecca

2010-01-01

Purpose: The authors had previously published measurements of the detectability of disk-shaped contrast objects in images obtained from a C-arm CT system. A simple approach based on Rose’s criterion was used to scale the date, assuming the threshold for the smallest diameter detected should be inversely proportional to (dose)1∕2. A more detailed analysis based on recent theoretical modeling of C-arm CT images is presented in this work. Methods: The signal and noise propagations in a C-arm based CT system have been formulated by other authors using cascaded systems analysis. They established a relationship between detectability and the noise equivalent quanta. Based on this model, the authors obtained a relation between x-ray dose and the diameter of the smallest disks detected. A closed form solution was established by assuming no rebinning and no resampling of data, with low additive noise and using a ramp filter. For the case when no such assumptions were made, a numerically calculated solution using previously reported imaging and reconstruction parameters was obtained. The detection probabilities for a range of dose and kVp values had been measured previously. These probabilities were normalized to a single dose of 56.6 mGy using the Rose-criteria-based relation to obtain a universal curve. Normalizations based on the new numerically calculated relationship were compared to the measured results. Results: The theoretical and numerical calculations have similar results and predict the detected diameter size to be inversely proportional to (dose)1∕3 and (dose)1∕2.8, respectively. The normalized experimental curves and the associated universal plot using the new relation were not significantly different from those obtained using the Rose-criterion-based normalization. Conclusions: From numerical simulations, the authors found that the diameter of detected disks depends inversely on the cube root of the dose. For observer studies for disks larger than 4 mm, the cube root as well as square root relations appear to give similar results when used for normalization. PMID:20527560

Evaluation of force-sensing resistors for gait event detection to trigger electrical stimulation to improve walking in the child with cerebral palsy.

PubMed

Smith, Brian T; Coiro, Daniel J; Finson, Richard; Betz, Randal R; McCarthy, James

2002-03-01

Force-sensing resistors (FSRs) were used to detect the transitions between five main phases of gait for the control of electrical stimulation (ES) while walking with seven children with spastic diplegia, cerebral palsy. The FSR positions within each child's insoles were customized based on plantar pressure profiles determined using a pressure-sensitive membrane array (Tekscan Inc., Boston, MA). The FSRs were placed in the insoles so that pressure transitions coincided with an ipsilateral or contralateral gait event. The transitions between the following gait phases were determined: loading response, mid- and terminal stance, and pre- and initial swing. Following several months of walking on a regular basis with FSR-triggered intramuscular ES to the hip and knee extensors, hip abductors, and ankle dorsi and plantar flexors, the accuracy and reliability of the FSRs to detect gait phase transitions were evaluated. Accuracy was evaluated with four of the subjects by synchronizing the output of the FSR detection scheme with a VICON (Oxford Metrics, U.K.) motion analysis system, which was used as the gait event reference. While mean differences between each FSR-detected gait event and that of the standard (VICON) ranged from +35 ms (indicating that the FSR detection scheme recognized the event before it actually happened) to -55 ms (indicating that the FSR scheme recognized the event after it occurred), the difference data was widely distributed, which appeared to be due in part to both intrasubject (step-to-step) and intersubject variability. Terminal stance exhibited the largest mean difference and standard deviation, while initial swing exhibited the smallest deviation and preswing the smallest mean difference. To determine step-to-step reliability, all seven children walked on a level walkway for at least 50 steps. Of 642 steps, there were no detection errors in 94.5% of the steps. Of the steps that contained a detection error, 80% were due to the failure of the FSR signal to reach the programmed threshold level during the transition to loading response. Recovery from an error always occurred one to three steps later.

Testing the snake-detection hypothesis: larger early posterior negativity in humans to pictures of snakes than to pictures of other reptiles, spiders and slugs.

PubMed

Van Strien, Jan W; Franken, Ingmar H A; Huijding, Jorg

2014-01-01

According to the snake detection hypothesis (Isbell, 2006), fear specifically of snakes may have pushed evolutionary changes in the primate visual system allowing pre-attentional visual detection of fearful stimuli. A previous study demonstrated that snake pictures, when compared to spiders or bird pictures, draw more early attention as reflected by larger early posterior negativity (EPN). Here we report two studies that further tested the snake detection hypothesis. In Study 1, we tested whether the enlarged EPN is specific for snakes or also generalizes to other reptiles. Twenty-four healthy, non-phobic women watched the random rapid serial presentation of snake, crocodile, and turtle pictures. The EPN was scored as the mean activity at occipital electrodes (PO3, O1, Oz, PO4, O2) in the 225-300 ms time window after picture onset. The EPN was significantly larger for snake pictures than for pictures of the other reptiles. In Study 2, we tested whether disgust plays a role in the modulation of the EPN and whether preferential processing of snakes also can be found in men. 12 men and 12 women watched snake, spider, and slug pictures. Both men and women exhibited the largest EPN amplitudes to snake pictures, intermediate amplitudes to spider pictures and the smallest amplitudes to slug pictures. Disgust ratings were not associated with EPN amplitudes. The results replicate previous findings and suggest that ancestral priorities modulate the early capture of visual attention.

A Bevel Gear Quality Inspection System Based on Multi-Camera Vision Technology.

PubMed

Liu, Ruiling; Zhong, Dexing; Lyu, Hongqiang; Han, Jiuqiang

2016-08-25

Surface defect detection and dimension measurement of automotive bevel gears by manual inspection are costly, inefficient, low speed and low accuracy. In order to solve these problems, a synthetic bevel gear quality inspection system based on multi-camera vision technology is developed. The system can detect surface defects and measure gear dimensions simultaneously. Three efficient algorithms named Neighborhood Average Difference (NAD), Circle Approximation Method (CAM) and Fast Rotation-Position (FRP) are proposed. The system can detect knock damage, cracks, scratches, dents, gibbosity or repeated cutting of the spline, etc. The smallest detectable defect is 0.4 mm × 0.4 mm and the precision of dimension measurement is about 40-50 μm. One inspection process takes no more than 1.3 s. Both precision and speed meet the requirements of real-time online inspection in bevel gear production.

Connecticut Coalition for Achievement Now. 2006-2007 Annual Report

ERIC Educational Resources Information Center

ConnCAN, 2007

2007-01-01

In January 2005, leaders from Connecticut's business, higher education and civic communities came together to create the Connecticut Coalition for Achievement Now (ConnCAN): a nonprofit organization designed to be a catalyst for the fundamental changes needed to move Connecticut from having the largest to having the smallest achievement gap in the…

Dramatic Change in Jupiter's Great Red Spot

NASA Technical Reports Server (NTRS)

Simon, A. A.; Wong, M. H.; Rogers, J. H.; Orton, G. S.; de Pater, I.; Asay-Davis, X.; Carlson, R. W.; Marcus, P. S.

2015-01-01

Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features, having been continuously observed since the 1800's. It currently spans the smallest latitude and longitude size ever recorded. Here we show analyses of 2014 Hubble spectral imaging data to study the color, structure and internal dynamics of this long-live storm.

Reliability and Usefulness of Linear Sprint Testing in Adolescent Rugby Union and League Players.

PubMed

Darrall-Jones, Joshua D; Jones, Ben; Roe, Gregory; Till, Kevin

2016-05-01

The purpose of this study was to evaluate (a) whether there were differences in sprint times at 5, 10, 20, 30, and 40 m between rugby union and rugby league players, (b) determine the reliability and usefulness of linear sprint testing in adolescent rugby players. Data were collected on 28 rugby union and league academy players over 2 testing sessions, with 3-day rest between sessions. Rugby league players were faster at 5 m than rugby union players, with further difference unclear. Sprint time at 10, 20, 30, and 40 m was all reliable (coefficient of variation [CV] = 3.1, 1.8, 2.0, and 1.3%) but greater than the smallest worthwhile change (SWC [0.2 × between-subject SD]), rating the test as marginal for usefulness. Although the test was incapable of detecting the SWC, we recommend that practitioners and researchers use Hopkins' proposed method; whereby plotting the change score of the individual at each split (±typical error [TE] expressed as a CV) against the SWC and visually inspecting whether the TE crosses into the SWC are capable of identifying whether a change is both real (greater than the noise of the test, i.e., >TE) and of practical significance (>SWC). Researchers and practitioners can use the TE and SWC from this study to assess changes in performance of adolescent rugby players when using single beam timing gates.

Breeding biology of the blue-gray noddy

USGS Publications Warehouse

Rauson, M.J.; Harrison, C.S.; Clapp, R.B.

1984-01-01

Blue-gray Noddies, the smallest marine terns, are similar in many respects to all tropical terns in Hawaii: single-egg clutches are laid, growth and development take about 7 weeks, breeding is colonial. Its small size results in eggs that comprise over 27% of adult body weight, compared to 15-20% for most marine terns (Langham 1983). Blue-gray Noddies are widespread in the tropical Pacific, but populations are generally small. This may be the result of its inshore feeding habits and the fact that it is a resident species (Diamond 1978). However, populations in the Hawaiian Archipelago are probably limited by the availability of suitable nest sites in cliffs or rocky outcrops, not food supplies..... Food habits in Hawaii confirm the unique dependence of this species on sea-striders but consumption may be seasonal Blue-gray Noddies take the smallest prey of any seabird in Hawaii and may feed on a lower trophic level..... The Hawaiian population is apparently heavier and produces larger eggs than Blue-gray Noddies elsewhere in the Pacific. This conforms with the general proposition that Hawaiian seabirds are larger than those in the central Pacific (Harrison et al. 1983). The Hawaiian population also has a more predictable breeding season than those farther south.This may be due to a greater seasonality of food supply, but the factors that control the timing of breeding are not clear. There does not appear to be any competition for nest sites with other seabirds.....Our information on growth and development will enable future investigators to estimate the ages of chicks during brief visits to Blue-gray Noddy colonies. This will facilitate programs that are designed to monitor the basic health of seabird populations and to detect changes from baseline that may result from human activities or oceanographic conditions.

The effect of viewing speech on auditory speech processing is different in the left and right hemispheres.

PubMed

Davis, Chris; Kislyuk, Daniel; Kim, Jeesun; Sams, Mikko

2008-11-25

We used whole-head magnetoencephalograpy (MEG) to record changes in neuromagnetic N100m responses generated in the left and right auditory cortex as a function of the match between visual and auditory speech signals. Stimuli were auditory-only (AO) and auditory-visual (AV) presentations of /pi/, /ti/ and /vi/. Three types of intensity matched auditory stimuli were used: intact speech (Normal), frequency band filtered speech (Band) and speech-shaped white noise (Noise). The behavioural task was to detect the /vi/ syllables which comprised 12% of stimuli. N100m responses were measured to averaged /pi/ and /ti/ stimuli. Behavioural data showed that identification of the stimuli was faster and more accurate for Normal than for Band stimuli, and for Band than for Noise stimuli. Reaction times were faster for AV than AO stimuli. MEG data showed that in the left hemisphere, N100m to both AO and AV stimuli was largest for the Normal, smaller for Band and smallest for Noise stimuli. In the right hemisphere, Normal and Band AO stimuli elicited N100m responses of quite similar amplitudes, but N100m amplitude to Noise was about half of that. There was a reduction in N100m for the AV compared to the AO conditions. The size of this reduction for each stimulus type was same in the left hemisphere but graded in the right (being largest to the Normal, smaller to the Band and smallest to the Noise stimuli). The N100m decrease for the Normal stimuli was significantly larger in the right than in the left hemisphere. We suggest that the effect of processing visual speech seen in the right hemisphere likely reflects suppression of the auditory response based on AV cues for place of articulation.

How to Choose Between Measures of Tinnitus Loudness for Clinical Research? A Report on the Reliability and Validity of an Investigator-Administered Test and a Patient-Reported Measure Using Baseline Data Collected in a Phase IIa Drug Trial.

PubMed

Hall, Deborah A; Mehta, Rajnikant L; Fackrell, Kathryn

2017-09-18

Loudness is a major auditory dimension of tinnitus and is used to diagnose severity, counsel patients, or as a measure of clinical efficacy in audiological research. There is no standard test for tinnitus loudness, but matching and rating methods are popular. This article provides important new knowledge about the reliability and validity of an audiologist-administered tinnitus loudness matching test and a patient-reported tinnitus loudness rating. Retrospective analysis of loudness data for 91 participants with stable subjective tinnitus enrolled in a randomized controlled trial of a novel drug for tinnitus. There were two baseline assessments (screening, Day 1) and a posttreatment assessment (Day 28). About 66%-70% of the variability from screening to Day 1 was attributable to the true score. But measurement error, indicated by the smallest detectable change, was high for both tinnitus loudness matching (20 dB) and tinnitus loudness rating (3.5 units). Only loudness rating captured a sensation that was meaningful to people who lived with the experience of tinnitus. The tinnitus loudness rating performed better against acceptability criteria for reliability and validity than did the tinnitus loudness matching test administered by an audiologist. But the rating question is still limited because it is a single-item instrument and is probably able to detect only large changes (at least 3.5 points).

Gold Nanoparticle Chemiresistor Arrays for Micro-Gas Chromatography Applications

NASA Astrophysics Data System (ADS)

Covington, Elizabeth Laura

Thiolate-monolayer-protected gold nanoparticle (MPN) chemiresistors were studied as the sensing devices for micro-gas chromatography (microGC) systems. Because transport through chemiresistors is dominated by tunneling, they are highly sensitive. In order to improve their limit of detection, their fundamental noise was studied. Chemiresistors exhibit 1/f type noise where noise scales inversely with frequency. Chemiresistor noise was found to scale inversely with MPN film thickness. We lowered the noise prefactor of a 50x60 microm2 chemiresistor by coating a thick rather than monolayer MPN film. Electron beam induced crosslinking (EBIX) of the MPN film slightly reduced chemiresistor noise. A technique for patterning chemiresistor arrays with MPN films using EBIX was developed, and an array with four distinct MPNs was fabricated in an area ˜600 microm 2. This is the smallest chemiresistor array reported to date. Chemiresistors were exposed to vapors and provided differential sensitivities comparable to those from larger uncrosslinked chemiresistors. Chemiresistors were studied to assess their long term stability. Chemiresistors exhibited decreases in resistance over time that is likely caused by loss of MPN ligands. Temperature dependent current-voltage measurements verified the resistance change was not due to changes in the size of the MPN core. While resistance could change by orders of magnitude, vapor sensitivity did not show significant changes. Heating increased the change in resistance, but chemiresistors remained responsive after being held at 80°C for a cumulative 400 hours. It was unknown whether tunneling in the MPN film is through the highest unoccupied molecular orbital (HOMO) or lowest unoccupied molecular orbital (LUMO). A new technique was explored to distinguish tunneling through the HOMO and LUMO by measuring the induced thermoelectric voltage caused by a temperature difference across the MPN film. For integration into a microGC system, we fabricated a chemiresistor array on the surface of a 2.2x2.2 mm2readout circuitry chip creating a monolithic sensor system. A model for determining the optimal sensor size for a microGC system is presented. While noise is inversely proportional to chemiresistor volume, the amount of analyte detectable is proportional to volume making smaller chemiresistors able to detect lesser amounts of analyte.

Li2 B12 and Li3 B12 : Prediction of the Smallest Tubular and Cage-like Boron Structures.

PubMed

Dong, Xue; Jalife, Said; Vásquez-Espinal, Alejandro; Ravell, Estefanía; Pan, Sudip; Cabellos, José Luis; Liang, Wei-Yan; Cui, Zhong-Hua; Merino, Gabriel

2018-04-16

An intriguing structural transition from the quasi-planar form of B 12 cluster upon the interaction with lithium atoms is reported. High-level computations show that the lowest energy structures of LiB 12 , Li 2 B 12 , and Li 3 B 12 have quasi-planar (C s ), tubular (D 6d ), and cage-like (C s ) geometries, respectively. The energetic cost of distorting the B 12 quasi-planar fragment is overcompensated by an enhanced electrostatic interaction between the Li cations and the tubular or cage-like B 12 fragments, which is the main reason of such drastic structural changes, resulting in the smallest tubular (Li 2 B 12 ) and cage-like (Li 3 B 12 ) boron structures reported to date. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Surface morphology and molecular bonding of CaCO3 nanocrystallites by gas diffusion method

NASA Astrophysics Data System (ADS)

Sulimai, N. H.; Rani, Rozina Abdul; Khusaimi, Z.; Abdullah, S.; Salifairus, M. J.; Alrokayan, Salman; Khan, Haseeb; Rusop, M.

2018-05-01

Calcium carbonate with the chemical formula of (CaCO3) is the most abundant element in the world. Its usage on certain applications is largely affected by its properties. The best means to control its properties is through controlled preparation of CaCO3. This study uses diffusion method between the precursors Calcium Chloride and Ammonium Carbonate. Instead of using water, ethanol was used to prepare the salt. Reaction was done in room temperature (RT) for 6h-24h. Smallest average crystallite size measured by FESEM micrograph is 500nm produced by synthesis of CaCO3 reacted for 168 hours. From energy-dispersive X-ray spectrum also indicated the smallest particle size is by CaCO3 reacted for 168 hours. Changes was seen for element Ca at 3.7keV.

Biofluid mechanics--an interdisciplinary research area of the future.

PubMed

Liepsch, Dieter

2006-01-01

Biofluid mechanics is a complex field that focuses on blood flow and the circulation. Clinical applications include bypass and anastomosis surgery, and the development of artificial heart valves and vessels, stents, vein and dialysis shunts. Biofluid mechanics is also involved in diagnostic and therapeutic measures, including CT and MRI, and ultrasound. The study of biofluid mechanics involves measuring blood flow, pressure, pulse wave, velocity distribution, the elasticity of the vessel wall, the flow behavior of blood to minimize complications in vessel,- neuro-, and heart surgery. Biofluid mechanics influence the lungs and circulatory system, the blood flow and micro-circulation; lymph flow, and artificial organs. Flow studies in arterial models can be done without invasive techniques on patients or animals. The results of fluid mechanic studies have shown that in the addition to basic biology, an understanding of the forces and movement on the cells is essential. Because biofluid mechanics allows for the detection of the smallest flow changes, it has an enormous potential for future cell research. Some of these will be discussed.

Temperature-Correlated Changes in Phytoplankton Community Structure Are Restricted to Polar Waters.

PubMed

Ward, Ben A

2015-01-01

Globally distributed observations of size-fractionated chlorophyll a and temperature were used to incorporate temperature dependence into an existing semi-empirical model of phytoplankton community size structure. The additional temperature-dependent term significantly increased the model's ability to both reproduce and predict observations of chlorophyll a size-fractionation at temperatures below 2°C. The most notable improvements were in the smallest (picoplankton) size-class, for which overall model fit was more than doubled, and predictive skill was increased by approximately 40%. The model was subsequently applied to generate global maps for three phytoplankton size classes, on the basis of satellite-derived estimates of surface chlorophyll a and sea surface temperature. Polar waters were associated with marked decline in the chlorophyll a biomass of the smallest cells, relative to lower latitude waters of equivalent total chlorophyll a. In the same regions a complementary increase was seen in the chlorophyll a biomass of larger size classes. These findings suggest that a warming and stratifying ocean will see a poleward expansion of the habitat range of the smallest phytoplankton, with the possible displacement of some larger groups that currently dominate. There was no evidence of a strong temperature dependence in tropical or sub-tropical regions, suggesting that future direct temperature effects on community structure at lower latitudes may be small.

Size dependent biodistribution and toxicokinetics of iron oxide magnetic nanoparticles in mice

NASA Astrophysics Data System (ADS)

Yang, Lin; Kuang, Huijuan; Zhang, Wanyi; Aguilar, Zoraida P.; Xiong, Yonghua; Lai, Weihua; Xu, Hengyi; Wei, Hua

2014-12-01

In spite of the immense benefits from iron oxide magnetic nanoparticles (IOMNs), there is scanty information regarding their metabolic activities and toxicity in vivo. In this study, we investigated the size dependent in vivo biodistribution, toxicokinetics, and toxicity and gene expression changes of various sizes of carboxyl coated IOMNs (diameters of 10, 20, 30, and 40 nm). Our findings demonstrated that the various sizes of IOMNs accumulated primarily in the liver and spleen on the first day post-injection. Interestingly, size dependent biodistribution and transport were observed: the smallest IOMNs (10 nm) showed the highest uptake by the liver, whereas the largest IOMNs (40 nm) showed the highest uptake by the spleen. Moreover, the IOMNs with the smallest size (10 nm) were cleared faster from the liver and kidneys, but more readily entered the brain and the uterus. IOMNs with the largest size (40 nm) accumulated more readily but were easily eliminated in the spleen. However, the level of iron in the heart decreased in all IOMN exposed groups. In addition, blood biochemistry, hematological analyses and histological examination demonstrated that there was no apparent acute toxicity caused by IOMNs in mice. However, smaller IOMNs (10 nm and 20 nm) more effectively changed the expression level of sensitive genes related to oxidant stress, iron transport, metabolic process, apoptosis, and others.In spite of the immense benefits from iron oxide magnetic nanoparticles (IOMNs), there is scanty information regarding their metabolic activities and toxicity in vivo. In this study, we investigated the size dependent in vivo biodistribution, toxicokinetics, and toxicity and gene expression changes of various sizes of carboxyl coated IOMNs (diameters of 10, 20, 30, and 40 nm). Our findings demonstrated that the various sizes of IOMNs accumulated primarily in the liver and spleen on the first day post-injection. Interestingly, size dependent biodistribution and transport were observed: the smallest IOMNs (10 nm) showed the highest uptake by the liver, whereas the largest IOMNs (40 nm) showed the highest uptake by the spleen. Moreover, the IOMNs with the smallest size (10 nm) were cleared faster from the liver and kidneys, but more readily entered the brain and the uterus. IOMNs with the largest size (40 nm) accumulated more readily but were easily eliminated in the spleen. However, the level of iron in the heart decreased in all IOMN exposed groups. In addition, blood biochemistry, hematological analyses and histological examination demonstrated that there was no apparent acute toxicity caused by IOMNs in mice. However, smaller IOMNs (10 nm and 20 nm) more effectively changed the expression level of sensitive genes related to oxidant stress, iron transport, metabolic process, apoptosis, and others. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr05061d

[The smallest toy dog from the Roman empire].

PubMed

Boessneck, J

1989-01-01

This study deals with osseous remains of the smallest breed of dogs found in deposits related to the Roman Imperial period. The bone material has been collected at the Colonia Ulpia Traiana near Xanten on the Rhine. It has been observed that the bones match in size with the smallest breeds of dogs known today.

Nozzle geometry for organic vapor jet printing

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

Forrest, Stephen R.; McGraw, Gregory

A first device is provided. The device includes a print head. The print head further includes a first nozzle hermetically sealed to a first source of gas. The first nozzle has an aperture having a smallest dimension of 0.5 to 500 microns in a direction perpendicular to a flow direction of the first nozzle. At a distance from the aperture into the first nozzle that is 5 times the smallest dimension of the aperture of the first nozzle, the smallest dimension perpendicular to the flow direction is at least twice the smallest dimension of the aperture of the first nozzle.

Nozzle geometry for organic vapor jet printing

DOEpatents

Forrest, Stephen R; McGraw, Gregory

2015-01-13

A first device is provided. The device includes a print head. The print head further includes a first nozzle hermetically sealed to a first source of gas. The first nozzle has an aperture having a smallest dimension of 0.5 to 500 microns in a direction perpendicular to a flow direction of the first nozzle. At a distance from the aperture into the first nozzle that is 5 times the smallest dimension of the aperture of the first nozzle, the smallest dimension perpendicular to the flow direction is at least twice the smallest dimension of the aperture of the first nozzle.

Minimally important change was estimated for the Manchester-Oxford Foot Questionnaire after foot/ankle surgery.

PubMed

Dawson, Jill; Boller, Irene; Doll, Helen; Lavis, Grahame; Sharp, Robert; Cooke, Paul; Jenkinson, Crispin

2014-06-01

To ascertain the smallest amounts of change for the three Manchester-Oxford Foot Questionnaire (MOXFQ) domains that are likely to be clinically meaningful and beyond measurement error for conditions affecting the foot/ankle. Estimates were compared with those from the Short-Form 36 (SF-36). A prospective observational study of 671 consecutive patients undergoing foot or ankle surgery at an orthopedic hospital. Before and 9 months after surgery, patients completed the MOXFQ and SF-36; transition items (anchor) asked about perceived changes in foot/ankle pain or problems since the surgery. Four hundred ninety-one patients completed pre- and postoperative questionnaires. Anchor-based minimal clinically important change (MCIC) values were ~13 points for each of the MOXFQ Walking/standing (W/S), Pain, and Social Interaction (S-I) domains [and greater than the standard error of measurement (SEM)]. MCIC values for all SF-36 domains fell within the SEM. Between-group MCIDs for the MOXFQ were W/S, 16.2; Pain, 9.9; S-I, 9.3. Distribution-based minimal detectable change (MDC90) values for the MOXFQ were ~11, ~12, and ~16 score points for the W/S, Pain, and S-I scales, respectively. This article provides information for aiding the interpretability of MOXFQ outcomes data and for planning future studies. The SF-36 is not recommended as a primary outcome for foot/ankle surgery. Copyright © 2014 Elsevier Inc. All rights reserved.

A Bevel Gear Quality Inspection System Based on Multi-Camera Vision Technology

PubMed Central

Liu, Ruiling; Zhong, Dexing; Lyu, Hongqiang; Han, Jiuqiang

2016-01-01

Surface defect detection and dimension measurement of automotive bevel gears by manual inspection are costly, inefficient, low speed and low accuracy. In order to solve these problems, a synthetic bevel gear quality inspection system based on multi-camera vision technology is developed. The system can detect surface defects and measure gear dimensions simultaneously. Three efficient algorithms named Neighborhood Average Difference (NAD), Circle Approximation Method (CAM) and Fast Rotation-Position (FRP) are proposed. The system can detect knock damage, cracks, scratches, dents, gibbosity or repeated cutting of the spline, etc. The smallest detectable defect is 0.4 mm × 0.4 mm and the precision of dimension measurement is about 40–50 μm. One inspection process takes no more than 1.3 s. Both precision and speed meet the requirements of real-time online inspection in bevel gear production. PMID:27571078

A Pragmatic Analysis of Discourse Particles in Filipino Computer Mediated Communication

ERIC Educational Resources Information Center

Palacio, May Antonette; Gustilo, Leah

2016-01-01

As the English language continues to evolve through time, many of its structures and functions changed, which made it even realizable that the smallest unit in a discourse can play a crucial role in communication. Hence, this present study is an attempt to investigate the phenomenon and further delve into the discourse-pragmatic functions of…

Comparison of two 6-minute walk tests to assess walking capacity in polio survivors.

PubMed

Brehm, Merel-Anne; Verduijn, Suzan; Bon, Jurgen; Bredt, Nicoline; Nollet, Frans

2017-11-21

To compare walking dynamics and test-retest reliability for 2 frequently applied walk tests in polio survivors: the 6-minute walk test (6MWT) to walk as far as possible; and the 6-minute walking energy cost test (WECT) at comfortable speed. Observational study. Thirty-three polio survivors, able to walk ≥ 150 m. On the same day participants performed a 6MWT and a WECT, which were repeated 1-3 weeks later. For each test, distance walked, heart rate and reduction in speed were assessed. The mean distance walked and mean heart rate were significantly higher in the 6MWT (441 m (standard deviation) (SD 79.7); 118 bpm (SD 19.2)) compared with the WECT (366 m (SD 67.3); 103 bpm (SD 14.3)); p< 0.001. Furthermore, during the 6MWT, patients continuously slowed down (-6%), while during the WECT speed dropped only slightly during the first 2 min, by -1.8% in total. Test-retest reliability of both tests was excellent (intraclass correlation coefficient (ICC) ≥ 0.95; lower bound 95% confidence interval (95% CI) ≥ 0.87). The smallest detectable change for the walked distance was 42 m (9.7% change from the mean) and 50 m (13.7%) on the 6MWT and WECT, respectively. Both the 6MWT and the WECT are reliable to assess walking capacity in polio survivors, with slightly superior sensitivity to detect change for the 6MWT. Differences in walking dynamics confirm that the tests cannot be used interchangeably. The 6MWT is recommended for measuring maximal walking capacity and the WECT for measuring submaximal walking capacity.

Test–retest reliability, validity, and minimum detectable change of visual analog, numerical rating, and verbal rating scales for measurement of osteoarthritic knee pain

PubMed Central

Alghadir, Ahmad H; Anwer, Shahnawaz; Iqbal, Amir; Iqbal, Zaheen Ahmed

2018-01-01

Objective Several scales are commonly used for assessing pain intensity. Among them, the numerical rating scale (NRS), visual analog scale (VAS), and verbal rating scale (VRS) are often used in clinical practice. However, no study has performed psychometric analyses of their reliability and validity in the measurement of osteoarthritic (OA) pain. Therefore, the present study examined the test–retest reliability, validity, and minimum detectable change (MDC) of the VAS, NRS, and VRS for the measurement of OA knee pain. In addition, the correlations of VAS, NRS, and VRS with demographic variables were evaluated. Methods The study included 121 subjects (65 women, 56 men; aged 40–80 years) with OA of the knee. Test–retest reliability of the VAS, NRS, and VRS was assessed during two consecutive visits in a 24 h interval. The validity was tested using Pearson’s correlation coefficients between the baseline scores of VAS, NRS, and VRS and the demographic variables (age, body mass index [BMI], sex, and OA grade). The standard error of measurement (SEM) and the MDC were calculated to assess statistically meaningful changes. Results The intraclass correlation coefficients of the VAS, NRS, and VRS were 0.97, 0.95, and 0.93, respectively. VAS, NRS, and VRS were significantly related to demographic variables (age, BMI, sex, and OA grade). The SEM of VAS, NRS, and VRS was 0.03, 0.48, and 0.21, respectively. The MDC of VAS, NRS, and VRS was 0.08, 1.33, and 0.58, respectively. Conclusion All the three scales had excellent test–retest reliability. However, the VAS was the most reliable, with the smallest errors in the measurement of OA knee pain. PMID:29731662

Ultrasound is a reproducible and valid tool for measuring scar height in children with burn scars: A cross-sectional study of the psychometric properties and utility of the ultrasound and 3D camera.

PubMed

Simons, M; Kee, E Gee; Kimble, R; Tyack, Z

2017-08-01

The aim of this study was to investigate the reproducibility and validity of measuring scar height in children using ultrasound and 3D camera. Using a cross-sectional design, children with discrete burn scars were included. Reproducibility was tested using Intraclass Correlation Coefficient (ICC) for reliability, and percentage agreement within 1mm between test and re-test, standard error of measurement (SEM), smallest detectable change (SDC) and Bland Altman limits of agreement for agreement. Concurrent validity was tested using Spearman's rho for support of pre-specified hypotheses. Forty-nine participants (55 scars) were included. For ultrasound, test-retest and inter-rater reproducibility of scar thickness was acceptable for scarred skin (ICC=0.95, SDC=0.06cm and ICC=0.82, SDC=0.14cm). The ultrasound picked up changes of <1mm. Inter-rater reproducibility of maximal scar height using the 3D camera was acceptable (ICC=0.73, SDC=0.55cm). Construct validity of the ultrasound was supported with a strong correlation between the measure of scar thickness and observer ratings of thickness using the POSAS (ρ=0.61). Construct validity of the 3D camera was also supported with a moderate correlation (ρ=0.37) with the same measure using maximal scar height. The ultrasound is capable of detecting smaller changes or differences in scar thickness than the 3D camera, in children with burn scars. However agreement as part of reproducibility was lower than expected between raters for the ultrasound. Improving the accuracy of scar relocation may go some way to address agreement. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

Effects of Voice Harmonic Complexity on ERP Responses to Pitch-Shifted Auditory Feedback

PubMed Central

Behroozmand, Roozbeh; Korzyukov, Oleg; Larson, Charles R.

2011-01-01

Objective The present study investigated the neural mechanisms of voice pitch control for different levels of harmonic complexity in the auditory feedback. Methods Event-related potentials (ERPs) were recorded in response to +200 cents pitch perturbations in the auditory feedback of self-produced natural human vocalizations, complex and pure tone stimuli during active vocalization and passive listening conditions. Results During active vocal production, ERP amplitudes were largest in response to pitch shifts in the natural voice, moderately large for non-voice complex stimuli and smallest for the pure tones. However, during passive listening, neural responses were equally large for pitch shifts in voice and non-voice complex stimuli but still larger than that for pure tones. Conclusions These findings suggest that pitch change detection is facilitated for spectrally rich sounds such as natural human voice and non-voice complex stimuli compared with pure tones. Vocalization-induced increase in neural responses for voice feedback suggests that sensory processing of naturally-produced complex sounds such as human voice is enhanced by means of motor-driven mechanisms (e.g. efference copies) during vocal production. Significance This enhancement may enable the audio-vocal system to more effectively detect and correct for vocal errors in the feedback of natural human vocalizations to maintain an intended vocal output for speaking. PMID:21719346

Testing the snake-detection hypothesis: larger early posterior negativity in humans to pictures of snakes than to pictures of other reptiles, spiders and slugs

PubMed Central

Van Strien, Jan W.; Franken, Ingmar H. A.; Huijding, Jorg

2014-01-01

According to the snake detection hypothesis (Isbell, 2006), fear specifically of snakes may have pushed evolutionary changes in the primate visual system allowing pre-attentional visual detection of fearful stimuli. A previous study demonstrated that snake pictures, when compared to spiders or bird pictures, draw more early attention as reflected by larger early posterior negativity (EPN). Here we report two studies that further tested the snake detection hypothesis. In Study 1, we tested whether the enlarged EPN is specific for snakes or also generalizes to other reptiles. Twenty-four healthy, non-phobic women watched the random rapid serial presentation of snake, crocodile, and turtle pictures. The EPN was scored as the mean activity at occipital electrodes (PO3, O1, Oz, PO4, O2) in the 225–300 ms time window after picture onset. The EPN was significantly larger for snake pictures than for pictures of the other reptiles. In Study 2, we tested whether disgust plays a role in the modulation of the EPN and whether preferential processing of snakes also can be found in men. 12 men and 12 women watched snake, spider, and slug pictures. Both men and women exhibited the largest EPN amplitudes to snake pictures, intermediate amplitudes to spider pictures and the smallest amplitudes to slug pictures. Disgust ratings were not associated with EPN amplitudes. The results replicate previous findings and suggest that ancestral priorities modulate the early capture of visual attention. PMID:25237303

A dual-beam spectropluviometer concept

NASA Astrophysics Data System (ADS)

Delahaye, J.-Y.; Barthès, L.; Golé, P.; Lavergnat, J.; Vinson, J. P.

2006-08-01

SummaryA dual beam spectropluviometer (DBS) measuring the equivalent diameter D, the fall velocity V and the time T of arrival of particles is presented. Its main advantage over previous optical disdrometers is the whole measurement range of atmospheric precipitating particles near the ground. In the bottom part of the size range, 0.1 mm has been the smallest observable diameter. The means for obtaining such results are (i) two uniform infrared beams of rectangular cross-section 2 mm in height, 40 mm in width and 250 mm in length, with a 2 mm vertical gap in-between, (ii) a dual 16-bit analog to digital converter, (iii) a dedicated program for extracting the three parameters in real time by computing the signal slopes and determining the correlation between both channels used in this first version of the instrument, (iv) various means for reducing spurious detections caused by splashing, vibration and sunlight. Laboratory tests and typical rain measurements are shown. The DBS is particularly suited for extensive atmospheric and radio propagation research applications where the smallest drops were not correctly estimated in the distributions because of the lack of appropriate measurement devices.

Development of a directional sensitive pressure and shear sensor

NASA Astrophysics Data System (ADS)

Wang, Wei-Chih; Dee, Jeffrey; Ledoux, William; Sangeorzan, Bruce; Reinhall, Per G.

2002-06-01

Diabetes mellitus is a disease that impacts the lives of millions of people around the world. Lower limb complications associated with diabetes include the development of plantar ulcers that can lead to infection and subsequent amputation. Shear stress is thought to be a major contributing factor to ulcer development, but due in part to technical difficulties with transducing shear stress, there is no widely used shear measurement sensor. As such, we are currently developing a directionally sensitive pressure/shear sensor based on fiber optic technology. The pressure/shear sensor consists of an array of optical fibers lying in perpendicular rows and columns separated by elastomeric pads. A map of pressure and shear stress is constructed based on observed macro bending through the intensity attenuation from the physical deformation of two adjacent perpendicular fibers. The sensor has been shown to have low noise and responded linearly to applied loads. The smallest detectable force on each sensor element based on the current setup is ~0.1 lbs. (0.4N). The smallest area we have resolved in our mesh sensor is currently ~1 cm2.

Detection thresholds for small haptic effects

NASA Astrophysics Data System (ADS)

Dosher, Jesse A.; Hannaford, Blake

2002-02-01

We are interested in finding out whether or not haptic interfaces will be useful in portable and hand held devices. Such systems will have severe constraints on force output. Our first step is to investigate the lower limits at which haptic effects can be perceived. In this paper we report on experiments studying the effects of varying the amplitude, size, shape, and pulse-duration of a haptic feature. Using a specific haptic device we measure the smallest detectable haptics effects, with active exploration of saw-tooth shaped icons sized 3, 4 and 5 mm, a sine-shaped icon 5 mm wide, and static pulses 50, 100, and 150 ms in width. Smooth shaped icons resulted in a detection threshold of approximately 55 mN, almost twice that of saw-tooth shaped icons which had a threshold of 31 mN.

Detection of core-periphery structure in networks based on 3-tuple motifs

NASA Astrophysics Data System (ADS)

Ma, Chuang; Xiang, Bing-Bing; Chen, Han-Shuang; Small, Michael; Zhang, Hai-Feng

2018-05-01

Detecting mesoscale structure, such as community structure, is of vital importance for analyzing complex networks. Recently, a new mesoscale structure, core-periphery (CP) structure, has been identified in many real-world systems. In this paper, we propose an effective algorithm for detecting CP structure based on a 3-tuple motif. In this algorithm, we first define a 3-tuple motif in terms of the patterns of edges as well as the property of nodes, and then a motif adjacency matrix is constructed based on the 3-tuple motif. Finally, the problem is converted to find a cluster that minimizes the smallest motif conductance. Our algorithm works well in different CP structures: including single or multiple CP structure, and local or global CP structures. Results on the synthetic and the empirical networks validate the high performance of our method.

ENERGY STAR and Green Buildings--Using ENERGY STAR Resources for Green Building Rating Systems: LEED[R], Green Globes[R] and CHPS

ERIC Educational Resources Information Center

Utebay, Kudret

2011-01-01

Every building, from the smallest school to the tallest skyscraper, uses energy. This energy is most often generated by burning fossil fuels, which releases greenhouse gases into the atmosphere and contributes to climate change. Existing commercial buildings offer a significant opportunity for low-cost, immediate emissions and energy cost…

The Tower and Glass Marbles Problem

ERIC Educational Resources Information Center

Denman, Richard T.; Hailey, David; Rothenberg, Michael

2010-01-01

The Catseye Marble company tests the strength of its marbles by dropping them from various levels of their office tower, to find the highest floor from which a marble will not break. We find the smallest number of drops required and from which floor each drop should be made. We also find out how these answers change if a restriction is placed on…

The Influence of College President Perceptions on Organizational Commitment to Higher Education Marketing: An Exploratory Analysis of High-Performing California Community Colleges

ERIC Educational Resources Information Center

Hall, Zachary M.

2008-01-01

Change, competition, and its consequences are particularly salient for California's community colleges. At its peak in 2002, California's community college system educated more than 2.5 million students annually. Nevertheless, California's community colleges receive the smallest proportion of the state education budget while enrolling nearly three…

Evaluation of Emerging Contaminants of Concern at the South District Wastewater Treatment Plant Based on Seasonal Events, Miami-Dade County, Florida, 2004

USGS Publications Warehouse

Lietz, Arthur C.; Meyer, Michael T.

2006-01-01

The Comprehensive Everglades Restoration Plan has identified highly treated wastewater as a possible water source for the restoration of natural water flows and hydroperiods in selected coastal areas, including the Biscayne Bay coastal wetlands. One potential source of reclaimed wastewater for the Biscayne Bay coastal wetlands is the effluent from the South District Wastewater Treatment Plant in southern Miami-Dade County. The U.S. Geological Survey, in cooperation with the Comprehensive Everglades Restoration Plan Wastewater Reuse Technology Pilot Project Delivery Team, initiated a study to assess the presence of emerging contaminants of concern in the South District Wastewater Treatment Plant influent and effluent using current wastewater-treatment methods. As part of the study, 24-hour composite and discrete samples were collected at six locations (influent at plants 1 and 2, effluent pump, reuse train, chlorine dioxide unit, and ultraviolet pilot unit) at the plant during: (1) a dry-season, low-flow event on March 2-3, 2004, with an average inflow rate of 83.7 million gallons per day; (2) a wet-season, average-flow event on July 20-21, 2004, with an average inflow rate of 89.7 million gallons per day; and (3) high-rate disinfection tests on October 5 and 20, 2004, with average flow rates of 84.1 and 119.6 million gallons per day, respectively. During these four sampling events, 26, 27, 29, and 35 constituents were detected, respectively. The following transformations in concentration were determined in the waste stream: -100 to 180 percent at the effluent pump and -100 to 85 percent at the reuse train on March 2-3, 2004, and -100 to 1,609 percent at the effluent pump and -100 to 832 percent at the reuse train on July 20-21, 2004; -100 to -37 percent at the effluent pump, -100 to -62 percent at the reuse train, -100 to -56 percent at the chlorine dioxide unit, and -100 to -40 percent at the ultraviolet pilot unit on October 5, 2004; and -100 to -4 percent at the effluent pump, -100 to 17 percent at the reuse train, -100 to -40 percent at the chlorine dioxide unit, and -100 to -14 percent at the ultraviolet pilot unit on October 20, 2004. Samples were tested for detection of household and industrial (organic) wastewater compounds, pharmaceutical compounds, antibiotic compounds, and hormones in influent. Two 'known' endocrine disrupting compounds?17 beta-estradiol (E2) and diethoxynonylphenol? and four 'suspected' endocrine-disrupting compounds?1,4-dichlorobenzene, benzophenone, tris(2-chloroethyl) phosphate, and tris(dichloroisopropyl) phosphate?were detected during these sampling events. Phenanthrene and indole showed the greatest concentration ranges and highest concentrations for the organic wastewater compounds. Acetaminophen showed the greatest concentration range and highest concentration, and warfarin showed the smallest concentration range for the pharmaceutical compounds. Sulfamethoxazole (a sulfonamide) showed the greatest concentration range and highest concentration, and sulfathiozole (also a sulfonamide) showed the smallest concentration range for the antibiotic compounds. Two hormones, 17 beta-estradiol (E2) and estrone (E1), were detected in influent. Samples were also tested for detection of organic wastewater compounds, pharmaceutical compounds, antibiotic compounds, and hormones in effluent. Indole showed the greatest concentration range and highest concentration, and triphenyl phosphate showed the smallest concentration range for the organic wastewater compounds. Dehydronifedipine showed the greatest concentration range and highest concentration, and warfarin had the smallest concentration range for the pharmaceutical compounds. Anhydro-erythromycin (a macrolide degradation product) showed the greatest concentration range, and sulfadiazine (a sulfonamide) and tetracycline showed the lowest concentration ranges for the antibiotic compounds. One hormone, 17 beta-estradiol (E2), was det

Color and translucency in silorane-based resin composite compared to universal and nanofilled composites.

PubMed

Pérez, María M; Ghinea, Razvan; Ugarte-Alván, Laura I; Pulgar, Rosa; Paravina, Rade D

2010-01-01

The purpose of this study was to determine the optical properties, color and translucency, of the new silorane-based resin composite and to compare it to universal dimethacrylate-based composites. Six dimethacrylate-based resin composites and one silorane-based resin composite (all A2 shade) were studied. Color of non-polymerized and polymerized composites was measured against white and black backgrounds using a spectroradiometer. Changes in color (ΔE*(ab)), translucency (ΔTP) and color coordinates (ΔL*, Δa* and Δb*) were calculated for each resin composite. Results were evaluated using a one-way ANOVA, a Tukey's test and a t-test. The polymerization-dependent ΔE*(ab) ranged from 4.7 to 9.1, with the smallest difference for the silorane-based resin composite. The color changes of silorane-based composite were due to the changes of coordinates Δa* and Δb*. However, for the dimethacrylate-based composites, the color changes mainly originated by ΔL*and Δb*. The silorane composite exhibited the smallest TP values. Tukey's test confirmed significant statistical differences (p<0.05) between mean TP values of Filtek Silorane and each brand of dimethacrylate-based composites before and after polymerization. The new silorane-based restorative system showed different optical properties compared to clinically successful dimethacrylate composites. The silorane composite exhibited better polymerization-dependent chromatic stability, and a lower translucency compared to other tested products. Copyright © 2010 Elsevier Ltd. All rights reserved.

Orofacial symptoms related to temporomandibular joint arthritis in juvenile idiopathic arthritis: smallest detectable difference in self-reported pain intensity.

PubMed

Stoustrup, Peter; Kristensen, Kasper D; Verna, Carlalberta; Küseler, Annelise; Herlin, Troels; Pedersen, Thomas K

2012-12-01

Temporomandibular joint (TMJ) inflammation in patients with juvenile idiopathic arthritis (JIA) may lead to mandibular growth disturbances and interfere with optimal joint and muscle function. Orofacial symptoms are common clinical findings in relation to TMJ arthritis in adolescence. Knowledge about their clinical manifestation is important for TMJ arthritis diagnosis, treatment choice, and outcome evaluation. The aim of our prospective observational study was to evaluate and describe the frequency, the main complaints, and the localization of TMJ arthritis-related orofacial symptoms. The smallest detectable differences (SDD) for minimal, average, and maximal pain were estimated. Thirty-three patients with JIA and arthritis-related orofacial symptoms in relation to 55 affected TMJ were included in our questionnaire study (mean age 14.11 yrs). Calculation of the SDD was based on a duplicate assessment 45 min after the first questionnaire was completed. The majority of the patients had common orofacial symptoms during mastication and maximal mouth opening procedures. Persistent orofacial symptoms were rare. The TMJ area in combination with the masseter muscle region was the orofacial region where symptoms were most common. The SDD for minimal, average, and maximal pain were between 10 and 14 mm on a visual analog scale. Our study offers new knowledge about TMJ arthritis-related orofacial symptoms that may aid diagnosis and clinical decision-making. We suggest that TMJ arthritis-related orofacial symptoms could be understood as products of the primary TMJ inflammation in combination with secondary myogenic and functional issues.

A Methodological Report: Adapting the 505 Change-of-Direction Speed Test Specific to American Football.

PubMed

Lockie, Robert G; Farzad, Jalilvand; Orjalo, Ashley J; Giuliano, Dominic V; Moreno, Matthew R; Wright, Glenn A

2017-02-01

Lockie, RG, Jalilvand, F, Orjalo, AJ, Giuliano, DV, Moreno, MR, and Wright, GA. A methodological report: Adapting the 505 change-of-direction speed test specific to American football. J Strength Cond Res 31(2): 539-547, 2017-The 505 involves a 10-m sprint past a timing gate, followed by a 180° change-of-direction (COD) performed over 5 m. This methodological report investigated an adapted 505 (A505) designed to be football-specific by changing the distances to 10 and 5 yd. Twenty-five high school football players (6 linemen [LM]; 8 quarterbacks, running backs, and linebackers [QB/RB/LB]; 11 receivers and defensive backs [R/DB]) completed the A505 and 40-yd sprint. The difference between A505 and 0 to 10-yd time determined the COD deficit for each leg. In a follow-up session, 10 subjects completed the A505 again and 10 subjects completed the 505. Reliability was analyzed by t-tests to determine between-session differences, typical error (TE), and coefficient of variation. Test usefulness was examined via TE and smallest worthwhile change (SWC) differences. Pearson's correlations calculated relationships between the A505 and 505, and A505 and COD deficit with the 40-yd sprint. A 1-way analysis of variance (p ≤ 0.05) derived between-position differences in the A505 and COD deficit. There were no between-session differences for the A505 (p = 0.45-0.76; intraclass correlation coefficient = 0.84-0.95; TE = 2.03-4.13%). Additionally, the A505 was capable of detecting moderate performance changes (SWC0.5 > TE). The A505 correlated with the 505 and 40-yard sprint (r = 0.58-0.92), suggesting the modified version assessed similar qualities. Receivers and defensive backs were faster than LM in the A505 for both legs, and right-leg COD deficit. Quarterbacks, running backs, and linebackers were faster than LM in the right-leg A505. The A505 is reliable, can detect moderate performance changes, and can discriminate between football position groups.

High inter-rater reliability, agreement, and convergent validity of Constant score in patients with clavicle fractures.

PubMed

Ban, Ilija; Troelsen, Anders; Kristensen, Morten Tange

2016-10-01

The Constant score (CS) has been the primary endpoint in most studies on clavicle fractures. However, the CS was not developed to assess patients with clavicle fractures. Our aim was to examine inter-rater reliability and agreement of the CS in patients with clavicle fractures. The secondary aim was to estimate the correlation between the CS and the Disabilities of the Arm, Shoulder and Hand score and the internal consistency of the 2 scores. On the basis of sample sizing, 36 patients (31 male and 5 female patients; mean age, 41.3 years) with clavicle fractures underwent standardized CS assessment at a mean of 6.8 weeks (SD, 1.0 weeks) after injury. Reliability and agreement of the CS were determined by 2 raters. The interclass correlation coefficient (ICC2,1), standard error of measurement, minimal detectable change, Cronbach α coefficient, and Pearson correlation coefficient were estimated. Inter-rater reliability of the total CS was excellent (interclass correlation coefficient, 0.94; 95% confidence interval, 0.88-0.97), with no systematic difference between the 2 raters (P = .75). The standard error of measurement (measurement error at the group level) was 4.9, whereas the minimal detectable change (smallest change needed to indicate a real change for an individual) was 13.6 CS points. The internal consistency of the 10 CS items was good, with a Cronbach α of .85, and we found a strong correlation (r = -0.92) between the CS and Disabilities of the Arm, Shoulder and Hand score. The CS was found to be reliable for assessing patients with clavicle fractures, especially at the group level. With high inter-rater reliability and agreement, in addition to good internal consistency, the standardized CS used in this study can be used for comparison of results from different settings. Copyright © 2016 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

Online monitoring of N-nitrosodimethylamine rejection as a performance indicator of trace organic chemical removal by reverse osmosis.

PubMed

Fujioka, Takahiro; Takeuchi, Haruka; Tanaka, Hiroaki; Kodamatani, Hitoshi

2018-06-01

The security of recycled water quality in potable reuse can be enhanced by improving the credibility of reverse osmosis (RO) treatment for the removal of trace organic chemicals (TOrCs). This study evaluated the potential of online monitoring of N-nitrosodimethylamine (NDMA) before and after RO treatment as a surrogate indicator for TOrC removal by RO. This pilot-scale study monitored NDMA concentrations in RO feedwater (ultrafiltration-treated wastewater) and RO permeate every 22 min using novel online NDMA analyzers-high-performance liquid chromatography followed by photochemical reaction and chemiluminescence detection. NDMA rejection by RO varied considerably in response to changes in operating conditions (permeate flux and feedwater temperature). A high linear correlation between NDMA rejection and the rejection of six other TOrCs was observed. The linear correlation was also identified for an RO membrane damaged with chlorine. The correlation between another potential surrogate indicator (conductivity rejection) and TOrC rejection was relatively low. NDMA, which is the smallest compound among regulated TOrCs, revealed rejections lower than the other TOrCs, indicating that NDMA rejection can be a conservative surrogate indicator capable of predicting changes in TOrC removal. Copyright © 2018 Elsevier Ltd. All rights reserved.

The MOBID-2 pain scale: Reliability and responsiveness to pain in patients with dementia

PubMed Central

Husebo, BS; Ostelo, R; Strand, LI

2014-01-01

Background Mobilization-Observation-Behavior-Intensity-Dementia-2 (MOBID-2) pain scale is a staff-administered pain tool for patients with dementia. This study explores MOBID-2's test–retest reliability, measurement error and responsiveness to change. Methods Analyses are based upon data from a cluster randomized trial including 352 patients with advanced dementia from 18 Norwegian nursing homes. Test–retest reliability between baseline and week 2 (n = 163), and weeks 2 and 4 (n = 159) was examined in patients not expected to change (controls), using intraclass correlation coefficient (ICC2.1), standard error of measurement (SEM) and smallest detectable change (SDC). Responsiveness was examined by testing six priori-formulated hypotheses about the association between change scores on MOBID-2 and other outcome measures. Results ICCs of the total MOBID-2 scores were 0.81 (0–2 weeks) and 0.85 (2–4 weeks). SEM and SDC were 1.9 and 3.1 (0–2 weeks) and 1.4 and 2.3 (2–4 weeks), respectively. Five out of six hypotheses were confirmed: MOBID-2 discriminated (p < 0.001) between change in patients with and without a stepwise protocol for treatment of pain (SPTP). Moderate association (r = 0.35) was demonstrated with Cohen-Mansfield Agitation Inventory, and no association with Mini-Mental State Examination, Functional Assessment Staging and Activity of Daily Living. Expected associations between change scores of MOBID-2 and Neuropsychiatric Inventory – Nursing Home version were not confirmed. Conclusion The SEM and SDC in connection with the MOBID-2 pain scale indicate that the instrument is responsive to a decrease in pain after a SPTP. Satisfactory test–retest reliability across test periods was demonstrated. Change scores ≥ 3 on total and subscales are clinically relevant and are beyond measurement error. PMID:24799157

The Behavioral Changes That Can Be Realized When Leaders Are Exposed to the Theories and Metaphors Found in Quantum Physics

ERIC Educational Resources Information Center

Godfrey, David Wayne

2009-01-01

Many are beginning to see the promise that the quantum world has offered those who manage and lead organizations (Wheatley, 1992; Zohar, 1997). The Newtonian world is one in which all "things" are reduced to their smallest parts, separated, divided, and analyzed with predictability, with complete control being the ultimate goal. The quantum world…

Preparation of calcium hydroxyapatite nanoparticles using microreactor and their characteristics of protein adsorption.

PubMed

Kandori, Kazuhiko; Kuroda, Tomohiko; Togashi, Shigenori; Katayama, Erika

2011-02-03

The calcium hydroxyapatite Ca(10)(PO(4))(6)(OH)(2) (Hap) nanoparticles were prepared by using microreactor and employed these Hap nanoparticles to clarify the adsorption behavior of proteins. The size of Hap particles produced by the microreactor reduced in the order of a hardness of the reaction conditions for mixing Ca(OH)(2) and H(3)PO(4) aqueous solutions, such as flow rates of both solutions and temperature. Finally, the size of the smallest Hap nanoparticle became 2 × 15 nm(2), similar to that of BSA molecule (4 × 14 nm(2)). It is noteworthy that the smallest Hap nanoparticles still possesses rodlike shape, suggesting that particles are grown along c-axis even though the reactants mixed very rapidly in narrow channels of the microreactors. The X-ray diffraction patterns of the Hap nanoparticles revealed that the crystallinity of the materials produced by the microreactor is low. The FTIR measurement indicated that the Hap nanoparticles produced by microreactor were carbonate-substituted type B Hap, where the carbonate ions replace the phosphate ions in the crystal lattice. All the adsorption isotherms of acidic bovine serum albumin (BSA), neutral myoglobin (MGB), and basic lysozyme (LSZ) onto Hap nanoparticles from 1 × 10(-4) mol/dm(3) KCl solution were the Langmuirian type. The saturated amounts of adsorbed BSA (n(S)(BSA)) for the Hap nanoparticles produced by microreactor were decreased with decrease in the mean particle length, and finally it reduced to zero for the smallest Hap nanoparticles. Similar results were observed for the adsorption of LSZ; the saturated amounts of adsorbed LSZ (n(S)(LSZ)) also reduced to zero for the smallest Hap nanoparticles. However, in the case of MGB, the saturated mounts of adsorbed MGB (n(S)(MGB)) are also depressed with decreased in their particle size, but about half of MGB molecules still adsorbed onto the smallest Hap nanoparticles. This difference in the protein adsorption behavior was explained by the difference in the size and flexibility of three kinds of proteins. The reduction of n(S)(BSA) is due to the decrease in the fraction of C sites on the side face of each Hap nanoparticle; i.e., there is not enough area left on the nanoparticle surface to adsorb large BSA molecules even though the BSA molecules are soft and their conformations are alterable. The reduction of n(S)(LSZ) was explained by the reduction of P sites. Further, rigidity of the LSZ molecules was given another possibility of the depression of n(S)(LSZ) for the Hap nanoparticles. However, MGB molecules with small and soft structure were adsorbed on the Hap nanoparticle surface by changing their conformation. We could control the amounts of adsorbed proteins by changing the particle size of Hap in the nanometer range and kinds of proteins. These obtained results may be useful for developing biomimetic materials for bone grafts and successful surgical devices in the biochemical field.

Radar investigation of asteroids

NASA Technical Reports Server (NTRS)

Ostro, S. J.

1981-01-01

Software to support all stages of asteroid radar observation and data analysis is developed. First-order analysis of all data in hand is complete. Estimates of radar cross sections, circular polarization ratios, and limb-to-limb echo spectral bandwidths for asteroids 7 Iris, 16 Psyche, 97 Klotho, 1862 Apollo, and 1915 Quetzalcoatl are reported. Radar observations of two previously unobserved asteroids were conducted. An Aten asteroid, 2100 Ra-Shalom, with the smallest known semimajor axis (0.83) was detected. Preliminary data reduction indicates a circular polarization ratio comparable to those of Apollo, Quetzalcoatl, and Toro.

Smallest worthwhile effect of land-based and water-based pulmonary rehabilitation for COPD.

PubMed

McNamara, Renae J; Elkins, Mark R; Ferreira, Manuela L; Spencer, Lissa M; Herbert, Robert D

2015-05-01

This study aimed to determine the smallest worthwhile effect of land-based and water-based pulmonary rehabilitation on 6-min walk distance among people with chronic obstructive pulmonary disease (COPD). Using a benefit-harm trade-off method, people with COPD who had completed two baseline 6-min walk tests at the commencement of outpatient pulmonary rehabilitation were presented with two scenarios: 8 weeks of land-based and 8 weeks of water-based pulmonary rehabilitation. Participants were guided through an iterative process allowing them to progressively refine their estimates of the smallest improvement due to each form of rehabilitation that would outweigh the associated costs, risks and inconvenience presented in the scenario. 100 people with COPD participated (mean±sd age 72±9 years, forced expiratory volume in 1 s 54±16% predicted and baseline 6-min walk distance 377±101 m). For land-based pulmonary rehabilitation, the median smallest worthwhile effect was 20 m (95% CI 15-37 m). For water-based pulmonary rehabilitation, the median smallest worthwhile effect was 26 m (95% CI 15-33 m). These estimates did not differ significantly (p=0.10). People with COPD typically perceive that pulmonary rehabilitation would be worthwhile if it increased the 6-min walk distance by about 6%. The smallest worthwhile effects of land- and water-based pulmonary rehabilitation were similar.

InGaAs/InAlAs single photon avalanche diode for 1550 nm photons.

PubMed

Meng, Xiao; Xie, Shiyu; Zhou, Xinxin; Calandri, Niccolò; Sanzaro, Mirko; Tosi, Alberto; Tan, Chee Hing; Ng, Jo Shien

2016-03-01

A single photon avalanche diode (SPAD) with an InGaAs absorption region, and an InAlAs avalanche region was designed and demonstrated to detect 1550 nm wavelength photons. The characterization included leakage current, dark count rate and single photon detection efficiency as functions of temperature from 210 to 294 K. The SPAD exhibited good temperature stability, with breakdown voltage dependence of approximately 45 mV K(-1). Operating at 210 K and in a gated mode, the SPAD achieved a photon detection probability of 26% at 1550 nm with a dark count rate of 1 × 10(8) Hz. The time response of the SPAD showed decreasing timing jitter (full width at half maximum) with increasing overbias voltage, with 70 ps being the smallest timing jitter measured.

InGaAs/InAlAs single photon avalanche diode for 1550 nm photons

PubMed Central

Xie, Shiyu; Zhou, Xinxin; Calandri, Niccolò; Sanzaro, Mirko; Tosi, Alberto; Tan, Chee Hing; Ng, Jo Shien

2016-01-01

A single photon avalanche diode (SPAD) with an InGaAs absorption region, and an InAlAs avalanche region was designed and demonstrated to detect 1550 nm wavelength photons. The characterization included leakage current, dark count rate and single photon detection efficiency as functions of temperature from 210 to 294 K. The SPAD exhibited good temperature stability, with breakdown voltage dependence of approximately 45 mV K−1. Operating at 210 K and in a gated mode, the SPAD achieved a photon detection probability of 26% at 1550 nm with a dark count rate of 1 × 108 Hz. The time response of the SPAD showed decreasing timing jitter (full width at half maximum) with increasing overbias voltage, with 70 ps being the smallest timing jitter measured. PMID:27069647

Density functional theory (DFT) study of a new novel bionanosensor hybrid; tryptophan/Pd doped single walled carbon nanotube

NASA Astrophysics Data System (ADS)

Yoosefian, Mehdi; Etminan, Nazanin

2016-07-01

In order to explore a new novel L-amino acid/transition metal doped single walled carbon nanotube based biosensor, density functional theory calculations were studied. These hybrid structures of organic-inorganic nanobiosensors are able to detect the smallest amino acid building block of proteins. The configurations of amine and carbonyl group coordination of tryptophan aromatic amino acid adsorbed on Pd/doped single walled carbon nanotube were compared. The frontier molecular orbital theory, quantum theory atom in molecule and natural bond orbital analysis were performed. The molecular electrostatic potential and the electron density surfaces were constructed. The calculations indicated that the Pd/SWCNT was sensitive to tryptophan suggesting the importance of interaction with biological molecule and potential detecting application. The proposed nanobiosensor represents a highly sensitive detection of protein at ultra-low concentration in diagnosis applications.

Diagnostic Capability of Peripapillary Three-dimensional Retinal Nerve Fiber Layer Volume for Glaucoma Using Optical Coherence Tomography Volume Scans.

PubMed

Khoueir, Ziad; Jassim, Firas; Poon, Linda Yi-Chieh; Tsikata, Edem; Ben-David, Geulah S; Liu, Yingna; Shieh, Eric; Lee, Ramon; Guo, Rong; Papadogeorgou, Georgia; Braaf, Boy; Simavli, Huseyin; Que, Christian; Vakoc, Benjamin J; Bouma, Brett E; de Boer, Johannes F; Chen, Teresa C

2017-10-01

To determine the diagnostic capability of peripapillary 3-dimensional (3D) retinal nerve fiber layer (RNFL) volume measurements from spectral-domain optical coherence tomography (OCT) volume scans for open-angle glaucoma (OAG). Assessment of diagnostic accuracy. Setting: Academic clinical setting. Total of 180 patients (113 OAG and 67 normal subjects). One eye per subject was included. Peripapillary 3D RNFL volumes were calculated for global, quadrant, and sector regions, using 4 different-size annuli. Peripapillary 2D RNFL thickness circle scans were also obtained. Area under the receiver operating characteristic curve (AUROC) values, sensitivity, specificity, positive and negative predictive values, positive and negative likelihood ratios. Among all 2D and 3D RNFL parameters, best diagnostic capability was associated with inferior quadrant 3D RNFL volume of the smallest annulus (AUROC value 0.977). Otherwise, global 3D RNFL volume AUROC values were comparable to global 2D RNFL thickness AUROC values for all 4 annulus sizes (P values: .0593 to .6866). When comparing the 4 annulus sizes for global RNFL volume, the smallest annulus had the best AUROC values (P values: .0317 to .0380). The smallest-size annulus may have the best diagnostic potential, partly owing to having no areas excluded for being larger than the 6 × 6 mm 2 scanned region. Peripapillary 3D RNFL volume showed excellent diagnostic performance for detecting glaucoma. Peripapillary 3D RNFL volume parameters have the same or better diagnostic capability compared to peripapillary 2D RNFL thickness measurements, although differences were not statistically significant. Copyright © 2017 Elsevier Inc. All rights reserved.

Hierarchical Formation of Dark Matter Halos near the Cutoff Scale and Their Impact on Indirect Detections

NASA Astrophysics Data System (ADS)

Ishiyama, Tomoaki

2015-08-01

The smallest dark matter halos are formed first in the early universe. We present results of very large cosmological N-body simulations of the hierarchical formation and evolution of halos over a wide mass range, beginning from the formation of the smallest halos. In the largest simulation, the motions of 40963 particles in comoving boxes of side lengths 400 pc and 200 pc were followed. The particle masses were 3.4 Χ 10-11 M⊙ and 4.3 Χ 10-12 M⊙, ensuring that halos at the cutoff scale were represented by ˜30,000 and ˜230,000 particles, respectively. We found that the central density cusp is much steeper in these halos than in larger halos (dwarf-galaxy-sized to cluster-sized halos), and scales as ρ ∝ r(-1.5—1.3). The cusp slope gradually becomes shallower as the halo mass increases. The slope of halos 50 times more massive than the smallest halo is approximately -1.3. No strong correlation exists between inner slope and the collapse epoch. The cusp slope of halos above the cutoff scale seems to be reduced primarily due to major merger processes. The concentration, estimated at the present universe, is predicted to be 60—70, consistent with theoretical models and earlier simulations, and ruling out simple power law mass-concentration relations. Such halos could still exist in the present universe with the same steep density profiles. Strongly depending on the subhalo mass function and the adopted concentration model, the steeper inner cusps of halos near the cutoff scale enhance the annihilation luminosity of a Milky Way sized halo between 12 to 67%.

[Hsp70 Genes of the Megaphragma amalphitanum (Hymenoptera: Trichogrammatidae) Parasitic Wasp].

PubMed

Chuvakova, L N; Sharko, F S; Nedoluzhko, A V; Polilov, A A; Prokhorchuk, E B; Skryabin, K G; Evgen'ev, M B

2017-01-01

Miniaturization is an evolutionary process that is widely represented in both invertebrates and vertebrates. Miniaturization frequently affects not only the size of the organism and its constituent cells, but also changes the genome structure and functioning. The structure of the main heat shock genes (hsp70 and hsp83) was studied in one of the smallest insects, the Megaphragma amalphitanum (Hymenoptera: Trichogrammatidae) parasitic wasp, which is comparable in size with unicellular organisms. An analysis of the sequenced genome has detected six genes that relate to the hsp70 family, some of which are apparently induced upon heat shock. Both induced and constitutively expressed hsp70 genes contain a large number of introns, which is not typical for the genes of this family. Moreover, none of the found genes form clusters, and they are all very heterogeneous (individual copies are only 75-85% identical), which indicates the absence of gene conversion, which provides the identity of genes of this family in Drosophila and other organisms. Two hsp83 genes, one of which contains an intron, have also been found in the M. amalphitanum genome.

Synchrotron-based ν-XRF mapping and μ-FTIR microscopy enable to look into the fate and effects of tattoo pigments in human skin.

PubMed

Schreiver, Ines; Hesse, Bernhard; Seim, Christian; Castillo-Michel, Hiram; Villanova, Julie; Laux, Peter; Dreiack, Nadine; Penning, Randolf; Tucoulou, Remi; Cotte, Marine; Luch, Andreas

2017-09-12

The increasing prevalence of tattoos provoked safety concerns with respect to particle distribution and effects inside the human body. We used skin and lymphatic tissues from human corpses to address local biokinetics by means of synchrotron X-ray fluorescence (XRF) techniques at both the micro (μ) and nano (ν) scale. Additional advanced mass spectrometry-based methodology enabled to demonstrate simultaneous transport of organic pigments, heavy metals and titanium dioxide from skin to regional lymph nodes. Among these compounds, organic pigments displayed the broadest size range with smallest species preferentially reaching the lymph nodes. Using synchrotron μ-FTIR analysis we were also able to detect ultrastructural changes of the tissue adjacent to tattoo particles through altered amide I α-helix to β-sheet protein ratios and elevated lipid contents. Altogether we report strong evidence for both migration and long-term deposition of toxic elements and tattoo pigments as well as for conformational alterations of biomolecules that likely contribute to cutaneous inflammation and other adversities upon tattooing.

Acetylene measurement in flames by chirp-based quantum cascade laser spectrometry.

PubMed

Quine, Zachary R; McNesby, Kevin L

2009-06-01

We have designed and characterized a mid-IR spectrometer built around a pulsed distributed-feedback quantum cascade laser using the characteristic frequency down-chirp to scan through the spectral region 6.5 cm(-1) spectral region. The behavior of this chirp is extensively measured. The accuracy and detection limits of the system as an absorption spectrometer are demonstrated first by measuring spectra of acetylene through a single pass 16 cm absorption cell in real time at low concentrations and atmospheric pressure. The smallest detectable peak is measured to be approximately 1.5 x 10(-4) absorbance units, yielding a minimum detectable concentration length product of 2.4 parts per million meter at standard temperature and pressure. This system is then used to detect acetylene within an ethylene-air opposed flow flame. Measurements of acetylene content as a function of height above the fuel source are presented, as well as measurements of acetylene produced in fuel breakdown as a function of preinjection fuel temperature.

Revealing Early Steps of α2β1 Integrin-mediated Adhesion to Collagen Type I by Using Single-Cell Force Spectroscopy

PubMed Central

Taubenberger, Anna; Cisneros, David A.; Friedrichs, Jens; Puech, Pierre-Henri; Muller, Daniel J.

2007-01-01

We have characterized early steps of α2β1 integrin-mediated cell adhesion to a collagen type I matrix by using single-cell force spectroscopy. In agreement with the role of α2β1 as a collagen type I receptor, α2β1-expressing Chinese hamster ovary (CHO)-A2 cells spread rapidly on the matrix, whereas α2β1-negative CHO wild-type cells adhered poorly. Probing CHO-A2 cell detachment forces over a contact time range of 600 s revealed a nonlinear adhesion response. During the first 60 s, cell adhesion increased slowly, and forces associated with the smallest rupture events were consistent with the breakage of individual integrin–collagen bonds. Above 60 s, a fraction of cells rapidly switched into an activated adhesion state marked by up to 10-fold increased detachment forces. Elevated overall cell adhesion coincided with a rise of the smallest rupture forces above the value required to break a single-integrin–collagen bond, suggesting a change from single to cooperative receptor binding. Transition into the activated adhesion mode and the increase of the smallest rupture forces were both blocked by inhibitors of actomyosin contractility. We therefore propose a two-step mechanism for the establishment of α2β1-mediated adhesion as weak initial, single-integrin–mediated binding events are superseded by strong adhesive interactions involving receptor cooperativity and actomyosin contractility. PMID:17314408

Synthesis and atomic scale characterization of Er2O3 nanoparticles: enhancement of magnetic properties and changes in the local structure

NASA Astrophysics Data System (ADS)

Corrêa, Eduardo L.; Bosch-Santos, Brianna; Freitas, Rafael S.; Potiens, Maria da Penha A.; Saiki, Mitiko; Carbonari, Artur W.

2018-05-01

In the investigation reported in this paper a modified thermal decomposition method was developed to produce very small Er2O3 nanoparticles (NPs). Particles structure, shape and size were characterized by x-ray diffraction and transmission electron microscopy which showed that the synthesis by thermal decomposition under O2 atmosphere produced very small and monodisperse NPs, allowing the investigation of finite-size and surface effects. Results of magnetization measurements showed that the smallest particles present the highest values of susceptibility that decrease as particle size increases. Specific heat measurements indicate that the sample with the smallest NPs (diameter ∼5 nm) has a Néel temperature of 0.54 K. The local structure of particles was investigated by measurements of hyperfine interactions with perturbed angular correlation spectroscopy using 111Cd as probe nuclei replacing the cationic sites. Results showed that the relative population of sites 8b increases in both the core and surface layer of particles.

Third-order nonlinear optical properties of ADP crystal

NASA Astrophysics Data System (ADS)

Wang, Mengxia; Wang, Zhengping; Chai, Xiangxu; Sun, Yuxiang; Sui, Tingting; Sun, Xun; Xu, Xinguang

2018-05-01

By using the Z-scan method, we investigated the third-order nonlinear optical (NLO) properties of ADP crystal at different wavelengths (355, 532, and 1064 nm) and different orientations ([001], [100], [110], I and II). The experimental data were fitted by NLO theory, to give out the two photon absorption (TPA) coefficient β 2 and the nonlinear refractive index n 2. When the light source changed from a 40 ps, 1064 nm fundamental laser to a 30 ps, 355 nm third-harmonic-generation (THG) laser, the β 2 value increased about 5 times (0.2 × 10‑2 → 1 × 10‑2 cm GW‑1), and the n 2 value increased about 1.5 times (1.5 × 10‑16 → 2.2 × 10‑16 cm2 W‑1). Among all of the orientations, the [110] sample exhibits the smallest β 2, and the second smallest n 2. It indicates that this orientation and its surroundings will be the preferred directions for high-power laser applications of ADP crystal.

Estimating linear-nonlinear models using Rényi divergences

PubMed Central

Kouh, Minjoon; Sharpee, Tatyana O.

2009-01-01

This paper compares a family of methods for characterizing neural feature selectivity using natural stimuli in the framework of the linear-nonlinear model. In this model, the spike probability depends in a nonlinear way on a small number of stimulus dimensions. The relevant stimulus dimensions can be found by optimizing a Rényi divergence that quantifies a change in the stimulus distribution associated with the arrival of single spikes. Generally, good reconstructions can be obtained based on optimization of Rényi divergence of any order, even in the limit of small numbers of spikes. However, the smallest error is obtained when the Rényi divergence of order 1 is optimized. This type of optimization is equivalent to information maximization, and is shown to saturate the Cramér-Rao bound describing the smallest error allowed for any unbiased method. We also discuss conditions under which information maximization provides a convenient way to perform maximum likelihood estimation of linear-nonlinear models from neural data. PMID:19568981

Estimating linear-nonlinear models using Renyi divergences.

PubMed

Kouh, Minjoon; Sharpee, Tatyana O

2009-01-01

This article compares a family of methods for characterizing neural feature selectivity using natural stimuli in the framework of the linear-nonlinear model. In this model, the spike probability depends in a nonlinear way on a small number of stimulus dimensions. The relevant stimulus dimensions can be found by optimizing a Rényi divergence that quantifies a change in the stimulus distribution associated with the arrival of single spikes. Generally, good reconstructions can be obtained based on optimization of Rényi divergence of any order, even in the limit of small numbers of spikes. However, the smallest error is obtained when the Rényi divergence of order 1 is optimized. This type of optimization is equivalent to information maximization, and is shown to saturate the Cramer-Rao bound describing the smallest error allowed for any unbiased method. We also discuss conditions under which information maximization provides a convenient way to perform maximum likelihood estimation of linear-nonlinear models from neural data.

Synthesis and atomic scale characterization of Er2O3 nanoparticles: enhancement of magnetic properties and changes in the local structure.

PubMed

Corrêa, Eduardo L; Bosch-Santos, Brianna; Freitas, Rafael S; da Penha A Potiens, Maria; Saiki, Mitiko; Carbonari, Artur W

2018-05-18

In the investigation reported in this paper a modified thermal decomposition method was developed to produce very small Er 2 O 3 nanoparticles (NPs). Particles structure, shape and size were characterized by x-ray diffraction and transmission electron microscopy which showed that the synthesis by thermal decomposition under O 2 atmosphere produced very small and monodisperse NPs, allowing the investigation of finite-size and surface effects. Results of magnetization measurements showed that the smallest particles present the highest values of susceptibility that decrease as particle size increases. Specific heat measurements indicate that the sample with the smallest NPs (diameter ∼5 nm) has a Néel temperature of 0.54 K. The local structure of particles was investigated by measurements of hyperfine interactions with perturbed angular correlation spectroscopy using 111 Cd as probe nuclei replacing the cationic sites. Results showed that the relative population of sites 8b increases in both the core and surface layer of particles.

An adaptive tracker for ShipIR/NTCS

NASA Astrophysics Data System (ADS)

Ramaswamy, Srinivasan; Vaitekunas, David A.

2015-05-01

A key component in any image-based tracking system is the adaptive tracking algorithm used to segment the image into potential targets, rank-and-select the best candidate target, and the gating of the selected target to further improve tracker performance. This paper will describe a new adaptive tracker algorithm added to the naval threat countermeasure simulator (NTCS) of the NATO-standard ship signature model (ShipIR). The new adaptive tracking algorithm is an optional feature used with any of the existing internal NTCS or user-defined seeker algorithms (e.g., binary centroid, intensity centroid, and threshold intensity centroid). The algorithm segments the detected pixels into clusters, and the smallest set of clusters that meet the detection criterion is obtained by using a knapsack algorithm to identify the set of clusters that should not be used. The rectangular area containing the chosen clusters defines an inner boundary, from which a weighted centroid is calculated as the aim-point. A track-gate is then positioned around the clusters, taking into account the rate of change of the bounding area and compensating for any gimbal displacement. A sequence of scenarios is used to test the new tracking algorithm on a generic unclassified DDG ShipIR model, with and without flares, and demonstrate how some of the key seeker signals are impacted by both the ship and flare intrinsic signatures.

Effects of voice harmonic complexity on ERP responses to pitch-shifted auditory feedback.

PubMed

Behroozmand, Roozbeh; Korzyukov, Oleg; Larson, Charles R

2011-12-01

The present study investigated the neural mechanisms of voice pitch control for different levels of harmonic complexity in the auditory feedback. Event-related potentials (ERPs) were recorded in response to+200 cents pitch perturbations in the auditory feedback of self-produced natural human vocalizations, complex and pure tone stimuli during active vocalization and passive listening conditions. During active vocal production, ERP amplitudes were largest in response to pitch shifts in the natural voice, moderately large for non-voice complex stimuli and smallest for the pure tones. However, during passive listening, neural responses were equally large for pitch shifts in voice and non-voice complex stimuli but still larger than that for pure tones. These findings suggest that pitch change detection is facilitated for spectrally rich sounds such as natural human voice and non-voice complex stimuli compared with pure tones. Vocalization-induced increase in neural responses for voice feedback suggests that sensory processing of naturally-produced complex sounds such as human voice is enhanced by means of motor-driven mechanisms (e.g. efference copies) during vocal production. This enhancement may enable the audio-vocal system to more effectively detect and correct for vocal errors in the feedback of natural human vocalizations to maintain an intended vocal output for speaking. Copyright © 2011 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

Is the Movement Assessment Battery for Children-2nd edition a reliable instrument to measure motor performance in 3 year old children?

PubMed

Smits-Engelsman, Bouwien C M; Niemeijer, Anuschka S; van Waelvelde, Hilde

2011-01-01

Formal testing of 3 year old children is a new feature in the revised version of the Movement Assessment Battery for Children (Movement ABC-2). Our study evaluated the reliability and explored the clinical applicability of the Movement ABC-2 Test in this young age group. A total of 50 typically children were given two trials of the test within a one to two week interval by two physical therapists: same assessor (n=28 children) and different assessors (n=22 children). Psychometric properties were evaluated by calculating internal consistency (Cronbach α), intra-class correlation (ICC), the standard error of measurement (SEM), the smallest detectable difference (SDD) and Kappa values for classification agreement. The results are promising for future implementation of the Movement ABC-2 in clinical practice. The children's performance was highly reproducible when tested by the same assessor (ICC .94) The SEM was 1.7 or 2.1 standard scores for 90% or 95% confidence intervals respectively, making the test sensitive enough to detect individual changes. If two different assessors tested the children the ICC was .76. In conclusion, the revised test can be applied to assess motor performance in typically developing 3-year old children. Future studies are needed to confirm if the same can be said for children with motor delays. Copyright © 2011 Elsevier Ltd. All rights reserved.

Organization of the nucleoli of soybean root meristematic cells at different states of their activity.

PubMed

Stepiński, Dariusz

2010-06-01

Internal organization of a nucleolus changes along with rRNA transcriptional activity. These changes mainly concern qualitative and quantitative alternations of three main nucleolar components: fibrillar centres (FC), dense fibrillar component (DFC) and granular component (GC). In the present work quantitative measurements of the number and sizes of FCs and DFCs in nucleoli of root meristematic cells of soybean seedlings grown at (1) chilling conditions that reduce transcriptional activity of soybean nucleoli (temp. of 10 degrees C) and at (2) conditions that increase this activity (recovery at optimal temp. of 25 degrees C after previous chilling), even more than (3) the control, have been carried out. Morphometric measurements showed that the highest number of FCs and DFCs was in the most active nucleoli, while the smallest number - in those with the lowest activity. The average size of an individual FC was similar in all nucleoli regardless of their transcriptional activity, that of the individual DFC varied, being bigger in the nucleoli of the chilled plants and smallest in those of the recovered plants. The numbers of FCs and DFCs seem to be indicators of transcriptional activity of plant nucleoli - the higher number of FCs and DFCs the more active nucleoli. Copyright 2009 Elsevier Ltd. All rights reserved.

A different approach on the onset of separation in the flow around a circular cylinder

NASA Astrophysics Data System (ADS)

Malamataris, Nikolaos; Sarris, I.; Pazis, D.; Liakos, A.

2016-11-01

The onset of separation in the flow around a cylinder is revisited with new insight. The goal of the research is to compute the smallest Reynolds number where the separation actual occurs rather than computing small eddies and extrapolating to the value of the Reynolds number where separation may occur. To this purpose, an accurate home made code is designed with Galerkin finite elements. The computational domain is chosen as the laboratory experiments by Taneda. It is found that in all six different choices of Taneda's diameters of the cylinders he used, separation is not observed for Re < 6 . 1 . Actually, separation is computed in all of his six cases for Re = 6 . 14 . Images of this smallest eddy are shown for the first time where all characteristics of eddies are recognisable (vortex centre, separation length etc). The vorticity of the flow is computed along the cylinder surface and it is shown that, at separation, vorticity changes sign. Byproducts of this research is the computation of the drag coefficient for Reynolds numbers starting from 1 .10-5 up to 40. In addition, the separation angle (point where vorticity changes sign) is computed for 6 . 14 <= Re <= 40 . This research aims to be the most thorough work done on that subject so far.

Changes to Articulatory Kinematics in Response to Loudness Cues in Individuals with Parkinson’s Disease

PubMed Central

Darling, Meghan; Huber, Jessica E.

2012-01-01

Purpose Individuals with Parkinson’s disease (PD) exhibit differences in displacement and velocity of the articulators as compared to older adults. The purpose of the current study was to examine effects of three loudness cues on articulatory movement patterns in individuals with PD. Methods Nine individuals diagnosed with idiopathic PD and 9 age- and sex- matched healthy controls produced sentences in four conditions: 1) comfortable loudness, 2) targeting 10dB above comfortable, 3) twice as loud as comfortable, and 4) in background noise. Lip and jaw kinematics and acoustic measurements were obtained. Results Both groups significantly increased sound pressure level (SPL) in the loud conditions as compared to comfortable. For the loud conditions, both groups had the highest SPL in background noise and 10dB and the lowest in twice as loud. Control participants produced the largest opening displacement in background noise and the smallest in twice as loud. Conversely, individuals with PD produced the largest opening displacement in twice as loud and the smallest in background noise. Conclusions Control participants and individuals with PD responded to cues to increase loudness in different ways. Changes in SPL may explain differences in kinematics for the control participants, but do not for individuals with PD. PMID:21386044

Effect of breeding protocols and reproductive tract score on reproductive performance of dairy heifers and economic outcome of breeding programs.

PubMed

Stevenson, J L; Rodrigues, J A; Braga, F A; Bitente, S; Dalton, J C; Santos, J E P; Chebel, R C

2008-09-01

The objectives of this study were to evaluate the effect of reproductive protocols and reproductive tract score on reproductive performance of dairy heifers and economic outcomes of breeding programs. Holstein heifers (n = 534), 13 +/- 1 mo of age, were randomly assigned to 1 of 4 reproductive protocols. On the day of enrollment (d 0), heifers were palpated per rectum and received a score according to the maturity of their reproductive tract (1 = prepubertal; 2 = peripubertal; and 3 = puber-tal). Estrous detection-control heifers (CON, n = 146) received no treatment and were inseminated on detection of estrus for 28 d. Prostaglandin F(2alpha)-treated heifers (PGED, n = 137) received 1 injection of PGF(2alpha) on d 0 and were inseminated on detection of estrus; heifers not in-seminated by d 14 received a second injection of PGF(2alpha) and were observed for estrus and artificial insemination (AI) for an additional 14 d. Heifers enrolled in the estrous detection-timed AI (EDTAI, n = 140) treatment received a controlled internal drug-release (CIDR) insert on d 0, and 7 d later, the CIDR was removed and all heifers received an injection of PGF(2alpha), heifers received AI on detection of estrus, and those not inseminated by 72 h after PGF(2alpha) received an injection of GnRH concurrent with AI. Heifers in the GnRH-timed AI (GTAI, n = 111) treatment received 1 injection of GnRH on d 0, on d 6 heifers received a CIDR insert and injections of GnRH and PGF(2alpha), on d 13 the CIDR was removed and heifers received an injection of PGF(2alpha), and 48 h later all heifers received an injection of GnRH and AI. Pregnancy was diagnosed at 32 +/- 3 and 62 +/- 3 d after AI. Cost of reproductive protocols and their economic outcomes were calculated for a 28 d period beginning at enrollment. Heifers in the PGED treatment were inseminated at a faster rate than CON heifers. A smaller proportion of prepubertal and peripubertal heifers were inseminated within 14 d of enrollment compared with pubertal heifers. Pregnancy per AI of CON and PGED heifers was greater compared with EDTAI and GTAI heifers. Proportion of GTAI heifers pregnant at the end of the 28-d breeding program was or tended to be smaller compared with PGED and CON heifers, respectively. Heifers in the CON and PGED treatments had the smallest cost per pregnancy followed by heifers in the EDTAI and GTAI treatments, respectively. When different scenarios were evaluated, however, the mean cost per pregnancy was smallest for PGED heifers. Cost per pregnancy generated was greatest for prepubertal heifers, whereas pubertal heifers had the smallest cost per pregnancy generated. Treatment of dairy heifers with PGF(2alpha) every 14 d until insemination and pregnancy results in the best economic outcomes, and screening heifers according to RTS may prove beneficial to identify heifers that may not be pubertal and would have compromised reproductive and economic performance in a breeding program.

Counting Particles Emitted by Stratospheric Aircraft and Measuring Size of Particles Emitted by Stratospheric Aircraft

NASA Technical Reports Server (NTRS)

Wilson, James Charles

1994-01-01

There were two principal objectives of the cooperative agreement between NASA and the University of Denver. The first goal was to modify the design of the ER-2 condensation nuclei counter (CNC) so that the effective lower detection limit would be improved at high altitudes. This improvement was sought because, in the instrument used prior to 1993, diffusion losses prevented the smallest detectable particles from reaching the detection volume of the instrument during operation at low pressure. Therefore, in spite of the sensor's ability to detect particles as small as 0.008 microns in diameter, many of these particles were lost in transport to the sensing region and were not counted. Most of the particles emitted by aircraft are smaller than 0.1 micron in diameter. At the start date of this work, May 1990, continuous sizing techniques available on the ER-2 were only capable of detecting particles larger than 0.17 micron. Thus, the second objective of this work was to evaluate candidate sizing techniques in an effort to gain additional information concerning the size of particles emitted by aircraft.

A Label-Free Microfluidic Biosensor for Activity Detection of Single Microalgae Cells Based on Chlorophyll Fluorescence

PubMed Central

Wang, Junsheng; Sun, Jinyang; Song, Yongxin; Xu, Yongyi; Pan, Xinxiang; Sun, Yeqing; Li, Dongqing

2013-01-01

Detection of living microalgae cells is very important for ballast water treatment and analysis. Chlorophyll fluorescence is an indicator of photosynthetic activity and hence the living status of plant cells. In this paper, we developed a novel microfluidic biosensor system that can quickly and accurately detect the viability of single microalgae cells based on chlorophyll fluorescence. The system is composed of a laser diode as an excitation light source, a photodiode detector, a signal analysis circuit, and a microfluidic chip as a microalgae cell transportation platform. To demonstrate the utility of this system, six different living and dead algae samples (Karenia mikimotoi Hansen, Chlorella vulgaris, Nitzschia closterium, Platymonas subcordiformis, Pyramidomonas delicatula and Dunaliella salina) were tested. The developed biosensor can distinguish clearly between the living microalgae cells and the dead microalgae cells. The smallest microalgae cells that can be detected by using this biosensor are 3 μm ones. Even smaller microalgae cells could be detected by increasing the excitation light power. The developed microfluidic biosensor has great potential for in situ ballast water analysis. PMID:24287532

Chemical Exchange Saturation Transfer (CEST) MR Technique for Liver Imaging at 3.0 Tesla: an Evaluation of Different Offset Number and an After-Meal and Over-Night-Fast Comparison.

PubMed

Deng, Min; Chen, Shu-Zhong; Yuan, Jing; Chan, Queenie; Zhou, Jinyuan; Wáng, Yì-Xiáng J

2016-04-01

This study seeks to explore whether chemical exchange saturation transfer (CEST) magnetic resonance imaging (MRI) can detect liver composition changes between after-meal and over-night-fast statuses. Fifteen healthy volunteers were scanned on a 3.0-T human MRI scanner in the evening 1.5-2 h after dinner and in the morning after over-night (12-h) fasting. Among them, seven volunteers were scanned twice to assess the scan-rescan reproducibility. Images were acquired at offsets (n = 41, increment = 0.25 ppm) from -5 to 5 ppm using a turbo spin echo (TSE) sequence with a continuous rectangular saturation pulse. Amide proton transfer-weighted (APTw) and GlycoCEST signals were quantified with the asymmetric magnetization transfer ratio (MTRasym) at 3.5 ppm and the total MTRasym integrated from 0.5 to 1.5 ppm from the corrected Z-spectrum, respectively. To explore scan time reduction, CEST images were reconstructed using 31 offsets (with 20% time reduction) and 21 offsets (with 40% time reduction), respectively. For reproducibility, GlycoCEST measurements in 41 offsets showed the smallest scan-rescan mean measurements variability, indicated by the lowest mean difference of -0.049% (95% limits of agreement, -0.209 to 0.111%); for APTw, the smallest mean difference was found to be 0.112% (95% limits of agreement, -0.698 to 0.921%) in 41 offsets. Compared with after-meal, both GlycoCEST measurement and APTw measurement under different offset number decreased after 12-h fasting. However, as the offsets number decreased (41 offsets vs. 31 offsets vs. 21 offsets), GlycoCEST map and APTw map became more heterogeneous and noisier. Our results show that CEST liver imaging at 3.0 T has high sensitivity for fasting.

Self-assembly of graphene oxide with a silyl-appended spiropyran dye for rapid and sensitive colorimetric detection of fluoride ions.

PubMed

Li, Yinhui; Duan, Yu; Zheng, Jing; Li, Jishan; Zhao, Wenjie; Yang, Sheng; Yang, Ronghua

2013-12-03

Fluoride ion (F(-)), the smallest anion, exhibits considerable significance in a wide range of environmental and biochemical processes. To address the two fundamental and unsolved issues of current F(-) sensors based on the specific chemical reaction (i.e., the long response time and low sensitivity) and as a part of our ongoing interest in the spiropyran sensor design, we reported here a new F(-) sensing approach that, via assembly of a F(-)-specific silyl-appended spiropyran dye with graphene oxide (GO), allows rapid and sensitive detection of F(-) in aqueous solution. 6-(tert-Butyldimethylsilyloxy)-1',3',3'-trimethylspiro [chromene- 2,2'-indoline] (SPS), a spiropyran-based silylated dye with a unique reaction activity for F(-), was designed and synthesized. The nucleophilic substitution reaction between SPS and F(-) triggers cleavage of the Si-O bond to promote the closed spiropyran to convert to its opened merocyanine form, leading to the color changing from colorless to orange-yellow with good selectivity over other anions. With the aid of GO, the response time of SPS for F(-) was shortened from 180 to 30 min, and the detection limit was lowered more than 1 order of magnitude compared to the free SPS. Furthermore, due to the protective effect of nanomaterials, the SPS/GO nanocomposite can function in a complex biological environment. The SPS/GO nanocomposite was characterized by XPS and AFM, etc., and the mechanism for sensing F(-) was studied by (1)H NMR and ESI-MS. Finally, this SPS/GO nanocomposite was successfully applied to monitoring F(-) in the serum.

Smallest worthwhile effect of land-based and water-based pulmonary rehabilitation for COPD

PubMed Central

Elkins, Mark R.; Ferreira, Manuela L.; Spencer, Lissa M.; Herbert, Robert D.

2015-01-01

This study aimed to determine the smallest worthwhile effect of land-based and water-based pulmonary rehabilitation on 6-min walk distance among people with chronic obstructive pulmonary disease (COPD). Using a benefit–harm trade-off method, people with COPD who had completed two baseline 6-min walk tests at the commencement of outpatient pulmonary rehabilitation were presented with two scenarios: 8 weeks of land-based and 8 weeks of water-based pulmonary rehabilitation. Participants were guided through an iterative process allowing them to progressively refine their estimates of the smallest improvement due to each form of rehabilitation that would outweigh the associated costs, risks and inconvenience presented in the scenario. 100 people with COPD participated (mean±sd age 72±9 years, forced expiratory volume in 1 s 54±16% predicted and baseline 6-min walk distance 377±101 m). For land-based pulmonary rehabilitation, the median smallest worthwhile effect was 20 m (95% CI 15–37 m). For water-based pulmonary rehabilitation, the median smallest worthwhile effect was 26 m (95% CI 15–33 m). These estimates did not differ significantly (p=0.10). People with COPD typically perceive that pulmonary rehabilitation would be worthwhile if it increased the 6-min walk distance by about 6%. The smallest worthwhile effects of land- and water-based pulmonary rehabilitation were similar. PMID:27730130

Detection-dependent kinetics as a probe of folding landscape microstructure.

PubMed

Yang, Wei Yuan; Gruebele, Martin

2004-06-30

The folding landscapes of polypeptides and proteins exhibit a hierarchy of local minima. The causes range from proline isomerization all the way down to microstructure in the free energy caused by residual frustration inherent in even the best 20 amino acid design. The corresponding time scales range from hours to submicroseconds. The smallest microstructures are difficult to detect. We have measured the folding/unfolding kinetics of the engineered trpzip2 peptide at different tryptophan fluorescence wavelengths, each yielding a different rate. Wavelength-dependent folding kinetics on 0.1-2 mus time scales show that different microstructures with a range of solvent exposure and local dynamics are populated. We estimate a lower limit for the roughness of the free energy surface based on the range of rates observed.

From Tornadoes to Earthquakes: Forecast Verification for Binary Events Applied to the 1999 Chi-Chi, Taiwan, Earthquake

NASA Astrophysics Data System (ADS)

Chen, C.; Rundle, J. B.; Holliday, J. R.; Nanjo, K.; Turcotte, D. L.; Li, S.; Tiampo, K. F.

2005-12-01

Forecast verification procedures for statistical events with binary outcomes typically rely on the use of contingency tables and Relative Operating Characteristic (ROC) diagrams. Originally developed for the statistical evaluation of tornado forecasts on a county-by-county basis, these methods can be adapted to the evaluation of competing earthquake forecasts. Here we apply these methods retrospectively to two forecasts for the m = 7.3 1999 Chi-Chi, Taiwan, earthquake. These forecasts are based on a method, Pattern Informatics (PI), that locates likely sites for future large earthquakes based on large change in activity of the smallest earthquakes. A competing null hypothesis, Relative Intensity (RI), is based on the idea that future large earthquake locations are correlated with sites having the greatest frequency of small earthquakes. We show that for Taiwan, the PI forecast method is superior to the RI forecast null hypothesis. Inspection of the two maps indicates that their forecast locations are indeed quite different. Our results confirm an earlier result suggesting that the earthquake preparation process for events such as the Chi-Chi earthquake involves anomalous changes in activation or quiescence, and that signatures of these processes can be detected in precursory seismicity data. Furthermore, we find that our methods can accurately forecast the locations of aftershocks from precursory seismicity changes alone, implying that the main shock together with its aftershocks represent a single manifestation of the formation of a high-stress region nucleating prior to the main shock.

Morphological changes in ultrafast laser ablation plumes with varying spot size.

PubMed

Harilal, S S; Diwakar, P K; Polek, M P; Phillips, M C

2015-06-15

We investigated the role of spot size on plume morphology during ultrafast laser ablation of metal targets. Our results show that the spatial features of fs LA plumes are strongly dependent on the focal spot size. Two-dimensional self-emission images showed that the shape of the ultrafast laser ablation plumes changes from spherical to cylindrical with an increasing spot size from 100 to 600 μm. The changes in plume morphology and internal structures are related to ion emission dynamics from the plasma, where broader angular ion distribution and faster ions are noticed for the smallest spot size used. The present results clearly show that the morphological changes in the plume with spot size are independent of laser pulse width.

Laplace-Fourier-domain dispersion analysis of an average derivative optimal scheme for scalar-wave equation

NASA Astrophysics Data System (ADS)

Chen, Jing-Bo

2014-06-01

By using low-frequency components of the damped wavefield, Laplace-Fourier-domain full waveform inversion (FWI) can recover a long-wavelength velocity model from the original undamped seismic data lacking low-frequency information. Laplace-Fourier-domain modelling is an important foundation of Laplace-Fourier-domain FWI. Based on the numerical phase velocity and the numerical attenuation propagation velocity, a method for performing Laplace-Fourier-domain numerical dispersion analysis is developed in this paper. This method is applied to an average-derivative optimal scheme. The results show that within the relative error of 1 per cent, the Laplace-Fourier-domain average-derivative optimal scheme requires seven gridpoints per smallest wavelength and smallest pseudo-wavelength for both equal and unequal directional sampling intervals. In contrast, the classical five-point scheme requires 23 gridpoints per smallest wavelength and smallest pseudo-wavelength to achieve the same accuracy. Numerical experiments demonstrate the theoretical analysis.

X-ray intravital microscopy for functional imaging in rat hearts using synchrotron radiation coronary microangiography

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

Umetani, K.; Fukushima, K.

2013-03-15

An X-ray intravital microscopy technique was developed to enable in vivo visualization of the coronary, cerebral, and pulmonary arteries in rats without exposure of organs and with spatial resolution in the micrometer range and temporal resolution in the millisecond range. We have refined the system continually in terms of the spatial resolution and exposure time. X-rays transmitted through an object are detected by an X-ray direct-conversion type detector, which incorporates an X-ray SATICON pickup tube. The spatial resolution has been improved to 6 {mu}m, yielding sharp images of small arteries. The exposure time has been shortened to around 2 msmore » using a new rotating-disk X-ray shutter, enabling imaging of beating rat hearts. Quantitative evaluations of the X-ray intravital microscopy technique were extracted from measurements of the smallest-detectable vessel size and detection of the vessel function. The smallest-diameter vessel viewed for measurements is determined primarily by the concentration of iodinated contrast material. The iodine concentration depends on the injection technique. We used ex vivo rat hearts under Langendorff perfusion for accurate evaluation. After the contrast agent is injected into the origin of the aorta in an isolated perfused rat heart, the contrast agent is delivered directly into the coronary arteries with minimum dilution. The vascular internal diameter response of coronary arterial circulation is analyzed to evaluate the vessel function. Small blood vessels of more than about 50 {mu}m diameters were visualized clearly at heart rates of around 300 beats/min. Vasodilation compared to the control was observed quantitatively using drug manipulation. Furthermore, the apparent increase in the number of small vessels with diameters of less than about 50 {mu}m was observed after the vasoactive agents increased the diameters of invisible small blood vessels to visible sizes. This technique is expected to offer the potential for direct investigation of mechanisms of vascular dysfunctions.« less

Are health inequalities really not the smallest in the Nordic welfare states? A comparison of mortality inequality in 37 countries.

PubMed

Popham, Frank; Dibben, Chris; Bambra, Clare

2013-05-01

Research comparing mortality by socioeconomic status has found that inequalities are not the smallest in the Nordic countries. This is in contrast to expectations given these countries' policy focus on equity. An alternative way of studying inequality has been little used to compare inequalities across welfare states and may yield a different conclusion. We used average life expectancy lost per death as a measure of total inequality in mortality derived from death rates from the Human Mortality Database for 37 countries in 2006 that we grouped by welfare state type. We constructed a theoretical 'lowest mortality comparator country' to study, by age, why countries were not achieving the smallest inequality and the highest life expectancy. We also studied life expectancy as there is an important correlation between it and inequality. On average, Nordic countries had the highest life expectancy and smallest inequalities for men but not women. For both men and women, Nordic countries had particularly low younger age mortality contributing to smaller inequality and higher life expectancy. Although older age mortality in the Nordic countries is not the smallest. There was variation within Nordic countries with Sweden, Iceland and Norway having higher life expectancy and smaller inequalities than Denmark and Finland (for men). Our analysis suggests that the Nordic countries do have the smallest inequalities in mortality for men and for younger age groups. However, this is not the case for women. Reducing premature mortality among older age groups would increase life expectancy and reduce inequality further in Nordic countries.

Are health inequalities really not the smallest in the Nordic welfare states? A comparison of mortality inequality in 37 countries

PubMed Central

Popham, Frank; Dibben, Chris; Bambra, Clare

2013-01-01

Background Research comparing mortality by socioeconomic status has found that inequalities are not the smallest in the Nordic countries. This is in contrast to expectations given these countries’ policy focus on equity. An alternative way of studying inequality has been little used to compare inequalities across welfare states and may yield a different conclusion. Methods We used average life expectancy lost per death as a measure of total inequality in mortality derived from death rates from the Human Mortality Database for 37 countries in 2006 that we grouped by welfare state type. We constructed a theoretical ‘lowest mortality comparator country’ to study, by age, why countries were not achieving the smallest inequality and the highest life expectancy. We also studied life expectancy as there is an important correlation between it and inequality. Results On average, Nordic countries had the highest life expectancy and smallest inequalities for men but not women. For both men and women, Nordic countries had particularly low younger age mortality contributing to smaller inequality and higher life expectancy. Although older age mortality in the Nordic countries is not the smallest. There was variation within Nordic countries with Sweden, Iceland and Norway having higher life expectancy and smaller inequalities than Denmark and Finland (for men). Conclusions Our analysis suggests that the Nordic countries do have the smallest inequalities in mortality for men and for younger age groups. However, this is not the case for women. Reducing premature mortality among older age groups would increase life expectancy and reduce inequality further in Nordic countries. PMID:23386671

Interpretability of Change Scores in Measures of Balance in People With COPD.

PubMed

Beauchamp, Marla K; Harrison, Samantha L; Goldstein, Roger S; Brooks, Dina

2016-03-01

Balance deficits and an increased fall risk are well documented in individuals with COPD. Despite evidence that balance training programs can improve performance on clinical balance tests, their minimal clinically important difference (MCID) is unknown. The aim of this study was to determine the MCID of the Berg Balance Scale (BBS), Balance Evaluation Systems Test (BESTest), and Activities-Specific Balance Confidence (ABC) scale in patients with COPD undergoing pulmonary rehabilitation. We performed a secondary analysis of data from two studies of balance training in COPD (n = 55). The MCID for each balance measure was estimated using the following anchor and distribution-based approaches: (1) mean change scores on a patient-reported global change in balance scale, (2) optimal cut-point from receiver operating characteristic curves (ROCs), and (3) the minimal detectable change with 95% confidence (MDC95). Data from 55 patients with COPD (mean age, 71.2 ± 7.1 y; mean FEV1, 39.2 ± 15.8% predicted) were used in the analysis. The smallest estimate of MCID was from the ROC method. Anchor-based estimates of the MCID ranged from 3.5 to 7.1 for the BBS, 10.2 to 17.4 for the BESTest, and 14.2 to 18.5 for the ABC scale; their MDC95 values were 5.0, 13.1, and 18.9, respectively. Among patients with COPD undergoing pulmonary rehabilitation, a change of 5 to 7 points for the BBS, 13 to 17 points for the BESTest, and 19 points for the ABC scale is required to be both perceptible to patients and beyond measurement error. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

Baseline and longitudinal change in isometric muscle strength prior to radiographic progression in osteoarthritic and pre-osteoarthritic knees--data from the Osteoarthritis Initiative.

PubMed

Eckstein, F; Hitzl, W; Duryea, J; Kent Kwoh, C; Wirth, W

2013-05-01

To test whether cross-sectional or longitudinal measures of thigh muscle isometric strength differ between knees with and without subsequent radiographic progression of knee osteoarthritis (KOA), with particular focus on pre-osteoarthritic female knees (knees with risk factors but without definite radiographic KOA). Of 4,796 Osteoarthritis Initiative participants, 2,835 knees with Kellgren Lawrence grade (KLG) 0-3 had central X-ray readings, annual quantitative joint space width (JSW) and isometric muscle strength measurements (Good strength chair). Separate slope analysis of covariance (ANCOVA) models were used to determine differences in strength between "progressor" and "non-progressor" knees, after adjusting for age, body mass index, and pain. 466 participant knees exceeded the smallest detectable JSW change during each of two observation intervals (year 2→4 and year 1→3) and were classified as progressors (213 women, 253 men; 128 KLG0/1, 330 KLG2/3); 946 participant knees did not exceed this threshold in either interval and were classified as non-progressors (588 women, 358 from men; 288KLG0/1, 658KLG2/3). Female progressor knees, including those with KLG0/1, tended to have lower extensor and flexor strength at year 2 and at baseline than those without progression, but the difference was not significant after adjusting for confounders. No significant difference was observed in longitudinal change of muscle strength (baseline→year 2) prior to radiographic progression. No significant differences were found for muscle strength in men, and none for change in strength concomitant with progression. This study provides no strong evidence that (changes in) isometric muscle strength precedes or is associated with structural (radiographic) progression of KOA. Copyright © 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Baseline and Longitudinal Change in Isometric Muscle Strength Prior to Radiographic Progression in Osteoarthritic and Pre-Osteoarthritic Knees- Data from the Osteoarthritis Initiative

PubMed Central

Eckstein, Felix; Hitzl, Wolfgang; Duryea, Jeff; Kwoh, C. Kent; Wirth, Wolfgang

2013-01-01

OBJECTIVE To test whether cross-sectional or longitudinal measures of thigh muscle isometric strength differ between knees with and without subsequent radiographic progression of knee osteoarthritis (KOA), with particular focus on pre-osteoarthritic female knees (knees with risk factors but without definite radiographic KOA). METHODS Of 4796 Osteoarthritis Initiative participants, 2835 knees with Kellgren Lawrence grade (KLG) 0–3 had central X-ray readings, annual quantitative joint space width (JSW) and isometric muscle strength measurements (Good strength chair). Separate slope ANCOVA models were used to determine differences in strength between “progressor” and “non- progressor” knees, after adjusting for age, body mass index, and pain. RESULTS 466 participant knees exceeded the smallest detectable JSW change during each of two observation intervals (year 2→4 and year 1→3) and were classified as progressors (213 women, 253 men; 128 KLG0/1, 330 KLG2/3); 946 participant knees did not exceed this threshold in either interval and were classified as non-progressors (588 women, 358 from men; 288KLG0/1, 658KLG2/3). Female progressor knees, including those with KLG0/1, tended to have lower extensor and flexor strength at year2 and at baseline than those without progression, but the difference was not significant after adjusting for confounders. No significant difference was observed in longitudinal change of muscle strength (baseline→year2) prior to radiographic progression. No significant differences were found for muscle strength in men, and none for change in strength concomitant with progression. CONCLUSION This study provides no strong evidence that (changes in) isometric muscle strength precedes or is associated with structural (radiographic) progression of KOA. PMID:23473978

Automated dynamic analytical model improvement for damped structures

NASA Technical Reports Server (NTRS)

Fuh, J. S.; Berman, A.

1985-01-01

A method is described to improve a linear nonproportionally damped analytical model of a structure. The procedure finds the smallest changes in the analytical model such that the improved model matches the measured modal parameters. Features of the method are: (1) ability to properly treat complex valued modal parameters of a damped system; (2) applicability to realistically large structural models; and (3) computationally efficiency without involving eigensolutions and inversion of a large matrix.

Estimation of fault geometry of a slow slip event off the Kii Peninsula, southwest of Japan, detected by DONET

NASA Astrophysics Data System (ADS)

Suzuki, K.; Nakano, M.; Hori, T.; Takahashi, N.

2015-12-01

The Japan Agency for Marine-Earth Science and Technology installed permanent ocean bottom observation network called Dense Oceanfloor Network System for Earthquakes and Tsunamis (DONET) off the Kii Peninsula, southwest of Japan, to monitor earthquakes and tsunamis. We detected the long-term vertical displacements of sea floor from the ocean-bottom pressure records, starting from March 2013, at several DONET stations (Suzuki et al., 2014). We consider that these displacements were caused by the crustal deformation due to a slow slip event (SSE). 　We estimated the fault geometry of the SSE by using the observed ocean-bottom displacements. The ocean-bottom displacements were obtained by removing the tidal components from the pressure records. We also subtracted the average of pressure changes taken over the records at stations connected to each science node from each record in order to remove the contributions due to atmospheric pressure changes and non-tidal ocean dynamic mass variations. Therefore we compared observed displacements with the theoretical ones that was subtracted the average displacement in the fault geometry estimation. We also compared observed and theoretical average displacements for the model evaluation. In this study, the observed average displacements were assumed to be zero. Although there are nine parameters in the fault model, we observed vertical displacements at only four stations. Therefore we assumed three fault geometries; (1) a reverse fault slip along the plate boundary, (2) a strike slip along a splay fault, and (3) a reverse fault slip along the splay fault. We obtained that the model (3) gives the smallest residual between observed and calculated displacements. We also observed that this SSE was synchronized with a decrease in the background seismicity within the area of a nearby earthquake cluster. In the future, we will investigate the relationship between the SSE and the seismicity change.

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

Harilal, S. S.; Diwakar, P. K.; Polek, M. P.

We investigated the role of spot size on plume morphology during ultrafast laser ablation of metal targets. Our results show that the spatial features of fs LA plumes are strongly dependent on the focal spot size. Two-dimensional self-emission images showed that the shape of the ultrafast laser ablation plumes changes from spherical to cylindrical with an increasing spot size from 100 to 600 μm. The changes in plume morphology and internal structures are related to ion emission dynamics from the plasma, where broader angular ion distribution and faster ions are noticed for the smallest spot size used. The present resultsmore » clearly show that the morphological changes in the plume with spot size are independent of laser pulse width.« less

With the Development of Teaching Sumo Robot are Discussed

NASA Astrophysics Data System (ADS)

quan, Miao Zhi; Ke, Ma; Xin, Wei Jing

In recent years, with of robot technology progress and robot science activities, robot technology obtained fast development. The system USES the Atmega128 single-chip Atmel company as a core controller, was designed using a infrared to tube detection boundary, looking for each other, controller to tube receiving infrared data, and according to the data control motor state thus robot reached automatic control purposes. Against robot by single-chip microcomputer smallest system, By making the teaching purpose is to promote the robot sumo students' interests and let more students to participate in the robot research activities.

Cytotoxic and aryl hydrocarbon hydroxylase-inducing effects of laboratory rodent diets. A cell culture study

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

Toerroenen, R.; Pelkonen, K.; Kaerenlampi, S.

1991-01-01

Extracts of several rodent diets were studied for their cytotoxic and aryl hydrocarbon hydroxylase-inducing properties by an in vitro method. The cell culture system based on a mouse hepatoma cell line (Hepa-1) was shown to be convenient and sensitive method for screening of diets for these parameters implying the presence of compounds potentially harmful in vivo. Considerable differences among diets and batches were detected. Smallest effects were observed with a semipurified diet and with the unrefined diet which - contrary to other four unrefined diets - contained no fish.

Longitudinal psychometric attributes, responsiveness, and importance of change: An approach using the SCOPA-Psychosocial questionnaire.

PubMed

Martínez-Martin, Pablo; Carod-Artal, Francisco Javier; da Silveira Ribeiro, Luciola; Ziomkowski, Sofia; Vargas, Antonio Pedro; Kummer, Wladimir; Mesquita, Hudson Mourão

2008-08-15

The objective of this study was to illustrate the analysis of longitudinal validity, responsiveness, and importance of change, using the SCOPA-Psychosocial Questionnaire (SCOPA-PS) as a source of empirical data. Sixty-seven patients with PD in Hoehn and Yahr (HY) stage 2 were followed up for 1 year and assessed by means of the Schwab and England Scale, Unified PD Rating Scale (UPDRS), Hospital Anxiety and Depression Scale (HADS), PDQ-39, and SCOPA-PS. A range of methods was applied to enable each of the target attributes to be analyzed from different conceptual stances. The SCOPA-PS displayed satisfactory acceptability (no floor or ceiling effect), internal consistency (alpha = 0.80-0.84), convergent validity (r(S) = 0.70-0.82 with PDQ-39), and precision (SEM = 8.80), both at baseline and at the end of follow-up. The threshold value for significant change ranged from 17.25 (1.96 SEM) to 24.39 (Smallest real difference and Reliable change index). Threshold values for a clinically meaningful change were 0.73-1.26 (effect size, standardized response mean, responsiveness statistic). Change in SCOPA-PS scores correlated strongly with change in total UPDRS, HADS, and PDQ-39 scores, and reliably detected 70% of cases that worsened according to the PDQ-39. The minimally important change (MIC) for "minimally impaired" patients as per the PDQ39 was 8.30-9.10 points. Indices such as 1.96 SEM, effect size, and correlation with the change in other measures provide useful information about different concepts of responsiveness. The MIC should be determined for each specific setting, using distribution- and anchor-based methods. The SCOPA-PS showed satisfactory longitudinal attributes and responsiveness in stage-2 Brazilian patients with PD across 1 year of follow-up. (c) 2008 Movement Disorder Society.

Finite Memory Walk and Its Application to Small-World Network

NASA Astrophysics Data System (ADS)

Oshima, Hiraku; Odagaki, Takashi

2012-07-01

In order to investigate the effects of cycles on the dynamical process on both regular lattices and complex networks, we introduce a finite memory walk (FMW) as an extension of the simple random walk (SRW), in which a walker is prohibited from moving to sites visited during m steps just before the current position. This walk interpolates the simple random walk (SRW), which has no memory (m = 0), and the self-avoiding walk (SAW), which has an infinite memory (m = ∞). We investigate the FMW on regular lattices and clarify the fundamental characteristics of the walk. We find that (1) the mean-square displacement (MSD) of the FMW shows a crossover from the SAW at a short time step to the SRW at a long time step, and the crossover time is approximately equivalent to the number of steps remembered, and that the MSD can be rescaled in terms of the time step and the size of memory; (2) the mean first-return time (MFRT) of the FMW changes significantly at the number of remembered steps that corresponds to the size of the smallest cycle in the regular lattice, where ``smallest'' indicates that the size of the cycle is the smallest in the network; (3) the relaxation time of the first-return time distribution (FRTD) decreases as the number of cycles increases. We also investigate the FMW on the Watts--Strogatz networks that can generate small-world networks, and show that the clustering coefficient of the Watts--Strogatz network is strongly related to the MFRT of the FMW that can remember two steps.

The Smallest Galaxies in the Universe: Investigating the Origins of Ultra-faint Galaxies

NASA Astrophysics Data System (ADS)

Qi, Yuewen; Graus, Andrew; Bullock, James

2018-01-01

One outstanding question in cosmology is, what are the smallest galaxies that can form? The answer to this question can tell us much about galaxy formation, and even of the properties of dark matter itself. A candidate for the smallest galaxies that can form are the ultrafaint galaxies. The star formation of ultrafaints appears to have been shut off during the epoch of reionization, when radiation from the first stars ionized all the free hydrogen in the universe. This would imply ultrafaints should exist everywhere in the universe. However, we can only observe ultrafaints as satellites of the Milky Way, due to their low brightness. This will change with the next generation of telescopes such as the Large Synoptic Survey Telescope (LSST). The focus of this work is to predict the number of ultrafaints that should be seen with future surveys. To that end, we use the ELVIS suite, which contains 14 dark matter only simulations of Local Group like systems containing a Milky Way and Andromeda-like galaxy and the substructure out to around 1 Mpc of the barycenter. We mock observe the simulations in order to mimic current surveys such as the Sloan Digital Sky Survey (SDSS), and the Dark Energy Survey (DES), and use the population of galaxies found by those surveys to project the population of dwarf galaxies out beyond the virial radius of either galaxy. This number will depend sensitively on the formation mechanism of ultrafaint dwarfs, and comparisons of future surveys to this work could help rule out certain formation scenarios.

THE SMALLEST FIELD OF DEFINITION OF A SUBGROUP OF THE GROUP \\mathrm{PSL}_2

NASA Astrophysics Data System (ADS)

Vinberg, È. B.

1995-02-01

As previously proved by the author, for each semisimple algebraic group of adjoint type that is dense in the Zariski topology there exists a smallest field of definition which is an invariant of the class of commensurable subgroups. In the present paper an algorithm is given for finding the smallest field of definition of a dense finitely generated subgroup of the group \\mathrm{PSL}_2(\\mathbb{C}). A criterion for arithmeticity of a lattice in \\mathrm{PSL}_2(\\mathbb{R}) or \\mathrm{PSL}_2(\\mathbb{C}) in terms of this field is presented.Bibliography: 7 titles.

Translation and Validation of the Dutch Western Ontario Meniscal Evaluation Tool.

PubMed

van der Wal, Robert J P; Heemskerk, Bastiaan T J; van Arkel, Ewoud R A; Mokkink, Lidwine B; Thomassen, Bregje J W

2017-05-01

The aim of this study was to translate the Western Ontario Meniscal Evaluation Tool (WOMET) into Dutch, to evaluate the content validity, construct validity, reliability, and responsiveness, and to determine the minimal important change (MIC) of the Dutch version. The WOMET was translated into Dutch according to a standardized forward-backward translation protocol. A total of 86 patients (51 males, 35 females, median age 52 years [interquartile range, 43-60 years]) with isolated meniscal pathology were included. The WOMET was completed three times; at baseline, around 2 weeks, and after 3 months from the baseline. Knee injury and osteoarthritis outcome score, International Knee Documentation Committee subjective knee form, short-form 36, and an anchor question were also answered. There were good results for content validity (floor and ceiling effects [< 15%]), construct validity (79% of the predefined hypotheses were confirmed), internal consistency (Cronbach α = 0.87, 0.79, and 0.86 for each subscale score), test-retest reliability (intraclass correlation coefficient = 0.78 for total WOMET score), and responsiveness (79% of the predefined hypotheses were confirmed). The smallest detectable change and MIC for the Dutch WOMET are 20.5 and 14.7, respectively. The Dutch version of the WOMET is valid and reliable for assessing health-related quality of life in patients with meniscal pathology. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Maximal Upper Body Strength and Oxygen Uptake are Associated with Performance in High-Level 200-M Sprint Kayakers.

PubMed

Pickett, Craig W; Nosaka, Kazunori; Zois, James; Hopkins, Will G; J, Anthony; Blazevich

2017-12-27

Current training and monitoring methods in sprint kayaking are based on the premise that upper-body muscular strength and aerobic power are both important for performance, but limited evidence exists to support this premise in high-level athletes. Relationships between measures of strength, maximal oxygen uptake (VO2max) and 200-m race times in kayakers competing at national-to-international levels were examined. Data collected from Australian Canoeing training camps and competitions for 7 elite, 7 national and 8 club level male sprint kayakers were analyzed for relationships between maximal isoinertial strength (3-RM bench press, bench row, chin-up and deadlift), VO2max on a kayak ergometer, and 200-m race time. Correlations between race time and bench press, bench row, chin-up, and VO2max were -0.80, -0.76, -0.73, -0.02 and 0.71, respectively (90% confidence limits ∼±0.17). The multiple correlation coefficient for 200-m race time with bench press and VO2max was 0.84. Errors in prediction of 200-m race time in regression analyses were extremely large (∼4%) in relation to the smallest important change of 0.3%. However, from the slopes of the regressions, the smallest important change could be achieved with a 1.4% (±0.5%) change in bench-press strength and a 0.9% (±0.5%) change in VO2max. Substantial relationships were found between upper-body strength or aerobic power and 200-m performances. These measures may not accurately predict individual performance times, but would be practicable for talent identification purposes. Training aimed at improving upper-body strength or aerobic power in lowerperforming athletes could also enhance the performance in 200-m kayak sprints.

Advances in the Surface Renewal Flux Measurement Method

NASA Astrophysics Data System (ADS)

Shapland, T. M.; McElrone, A.; Paw U, K. T.; Snyder, R. L.

2011-12-01

The measurement of ecosystem-scale energy and mass fluxes between the planetary surface and the atmosphere is crucial for understanding geophysical processes. Surface renewal is a flux measurement technique based on analyzing the turbulent coherent structures that interact with the surface. It is a less expensive technique because it does not require fast-response velocity measurements, but only a fast-response scalar measurement. It is therefore also a useful tool for the study of the global cycling of trace gases. Currently, surface renewal requires calibration against another flux measurement technique, such as eddy covariance, to account for the linear bias of its measurements. We present two advances in the surface renewal theory and methodology that bring the technique closer to becoming a fully independent flux measurement method. The first advance develops the theory of turbulent coherent structure transport associated with the different scales of coherent structures. A novel method was developed for identifying the scalar change rate within structures at different scales. Our results suggest that for canopies less than one meter in height, the second smallest coherent structure scale dominates the energy and mass flux process. Using the method for resolving the scalar exchange rate of the second smallest coherent structure scale, calibration is unnecessary for surface renewal measurements over short canopies. This study forms the foundation for analysis over more complex surfaces. The second advance is a sensor frequency response correction for measuring the sensible heat flux via surface renewal. Inexpensive fine-wire thermocouples are frequently used to record high frequency temperature data in the surface renewal technique. The sensible heat flux is used in conjunction with net radiation and ground heat flux measurements to determine the latent heat flux as the energy balance residual. The robust thermocouples commonly used in field experiments underestimate the sensible heat flux, yielding results that are less than 50% of the sensible heat flux measured with finer sensors. We present the methodology for correcting the thermocouple signal to avoid underestimating the heat flux at both the smallest and the second smallest coherent structure scale.

Color stability of pigmented maxillofacial silicone elastomer: effects of nano-oxides as opacifiers.

PubMed

Han, Ying; Zhao, Yimin; Xie, Chao; Powers, John M; Kiat-amnuay, Sudarat

2010-01-01

This study evaluated the effects of nano-oxides on the color stability of pigmented silicone A-2186 maxillofacial prosthetic elastomers before and after artificial aging. Each of three widely used UV-shielding nano-sized particle oxides (TiO(2), ZnO, CeO(2)), based on recent survey of the industry at 1%, 2%, 2.5% concentrations were combined with each of five intrinsic silicone pigment types (no pigments, red, yellow, blue, and a mixture of the three pigments). Silicone A-2186 without nano-oxides or pigments served as control, for a total of 46 experimental groups of elastomers. In each group of the study, all specimens were aged in an artificial aging chamber for an energy exposure of 450kJ/m(2). CIE L*a*b* values were measured by a spectrophotometer. The 50:50% perceptibility (ΔE*=1.1) and acceptability threshold (ΔE*=3.0) were used in interpretation of recorded color differences. Color differences after aging were subjected to three-way analysis of variance. Means were compared by Fisher's PLSD intervals at the 0.05 level of significance. Yellow pigments mixed with all three nano-oxides at all intervals increased ΔE* values significantly from 3.7 up to 8.4. When mixed pigment groups were considered, TiO(2) at 2%, and 2.5% exhibited the smallest color changes, followed by ZnO and CeO(2), respectively (p<0.001). At 1%, CeO(2) exhibited the smallest color changes, followed by TiO(2) and ZnO, respectively (p<0.001). The smallest color differences, observed for nano-oxides groups, were recorded for CeO(2) at 1%, and TiO(2) at 2% and 2.5%. When the nano-oxides were tested at all concentrations, CeO(2) groups overall had the most color changes, and TiO(2) groups had the least. All ΔE* values of the mixed pigment groups were below the 50:50% acceptability threshold (ΔE*=1.2-2.3, below 3.0) except 2% CeO(2) (ΔE*=4.2). 1% nano-CeO(2) and 2% and 2.5% nano-TiO(2) used as opacifiers for silicone A-2186 maxillofacial prostheses with mixed pigments exhibited the least color changes when subjected to artificial aging at 450kJ/m(2). Yellow silicone pigment mixed with all three nano-oxides significantly affected color stability of A-2186 silicone elastomer. Copyright © 2010 Elsevier Ltd. All rights reserved.

Predicting the performance of local seismic networks using Matlab and Google Earth.

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

Chael, Eric Paul

2009-11-01

We have used Matlab and Google Earth to construct a prototype application for modeling the performance of local seismic networks for monitoring small, contained explosions. Published equations based on refraction experiments provide estimates of peak ground velocities as a function of event distance and charge weight. Matlab routines implement these relations to calculate the amplitudes across a network of stations from sources distributed over a geographic grid. The amplitudes are then compared to ambient noise levels at the stations, and scaled to determine the smallest yield that could be detected at each source location by a specified minimum number ofmore » stations. We use Google Earth as the primary user interface, both for positioning the stations of a hypothetical local network, and for displaying the resulting detection threshold contours.« less

All about Eve: Secret Sharing using Quantum Effects

NASA Technical Reports Server (NTRS)

Jackson, Deborah J.

2005-01-01

This document discusses the nature of light (including classical light and photons), encryption, quantum key distribution (QKD), light polarization and beamsplitters and their application to information communication. A quantum of light represents the smallest possible subdivision of radiant energy (light) and is called a photon. The QKD key generation sequence is outlined including the receiver broadcasting the initial signal indicating reception availability, timing pulses from the sender to provide reference for gated detection of photons, the sender generating photons through random polarization while the receiver detects photons with random polarization and communicating via data link to mutually establish random keys. The QKD network vision includes inter-SATCOM, point-to-point Gnd Fiber and SATCOM-fiber nodes. QKD offers an unconditionally secure method of exchanging encryption keys. Ongoing research will focus on how to increase the key generation rate.

Digital image processing of nanometer-size metal particles on amorphous substrates

NASA Technical Reports Server (NTRS)

Soria, F.; Artal, P.; Bescos, J.; Heinemann, K.

1989-01-01

The task of differentiating very small metal aggregates supported on amorphous films from the phase contrast image features inherently stemming from the support is extremely difficult in the nanometer particle size range. Digital image processing was employed to overcome some of the ambiguities in evaluating such micrographs. It was demonstrated that such processing allowed positive particle detection and a limited degree of statistical size analysis even for micrographs where by bare eye examination the distribution between particles and erroneous substrate features would seem highly ambiguous. The smallest size class detected for Pd/C samples peaks at 0.8 nm. This size class was found in various samples prepared under different evaporation conditions and it is concluded that these particles consist of 'a magic number' of 13 atoms and have cubooctahedral or icosahedral crystal structure.

Interfacing of differential-capacitive biomimetic hair flow-sensors for optimal sensitivity

NASA Astrophysics Data System (ADS)

Dagamseh, A. M. K.; Bruinink, C. M.; Wiegerink, R. J.; Lammerink, T. S. J.; Droogendijk, H.; Krijnen, G. J. M.

2013-03-01

Biologically inspired sensor-designs are investigated as a possible path to surpass the performance of more traditionally engineered designs. Inspired by crickets, artificial hair sensors have shown the ability to detect minute flow signals. This paper addresses developments in the design, fabrication, interfacing and characterization of biomimetic hair flow-sensors towards sensitive high-density arrays. Improvement of the electrode design of the hair sensors has resulted in a reduction of the smallest hair movements that can be measured. In comparison to the arrayed hairs-sensor design, the detection-limit was arguably improved at least twelve-fold, down to 1 mm s-1 airflow amplitude at 250 Hz as measured in a bandwidth of 3 kHz. The directivity pattern closely resembles a figure-of-eight. These sensitive hair-sensors open possibilities for high-resolution spatio-temporal flow pattern observations.

Remote sensing of vigor loss in conifers due to dwarf mistletoe

NASA Technical Reports Server (NTRS)

Meyer, M. P.; French, D. W.; Latham, R. P.; Nelson, C. A.; Douglass, R. W.

1971-01-01

The initial operation of a multiband/multidate tower-tramway test site in northeastern Minnesota for the development of specifications for subsequent multiband aerial photography of more extensive study areas was completed. Multiband/multidate configurations suggested by the tower-tramway studies were and will be flown with local equipment over the Togo test site. This site was photographed by the NASA RB57F aircraft in August and September 1971. It appears that, of all the film/filter combinations attempted to date (including optical recombining of several spectral band images via photo enhancement techniques), Ektachrome infrared film with a Wratten 12 filter is the best for detecting dwarf mistletoe, and other tree diseases as well. Using this film/filter combination, infection centers are easily detectable even on the smallest photo scale (1:100,000) obtained on the Togo site.

Silicon avalanche photodiodes developed at the Institute of Electron Technology

NASA Astrophysics Data System (ADS)

Wegrzecka, Iwona; Wegrzecki, Maciej; Bar, Jan; Grynglas, Maria; Uszynski, Andrzej; Grodecki, Remigiusz; Grabiec, Piotr B.; Krzeminski, Sylwester; Budzynski, Tadeusz

2004-07-01

Silicon avalanche photodiodes (APDs) -- due to the effect of avalanche multiplication of carriers in their structure -- are most sensitive and fastest detectors of visible and near infrared radiation. Also the value of noise equivalent power NEP of these detectors is the smallest. In the paper, the design, technology and properties of the silicon avalanche photodiodes with a n+ - p - π - p+ epiplanar structure developed at the Institute of Electron Technology (ITE) are presented. The diameters of photosensitive area range from 0.3 mm to 5 mm. The ITE photodiodes are optimized for the detection of the 800 nm - 850 nm radiation, but the detailed research on spectral dependencies of the gain and noise parameters has revealed that the spectral operating range of the ITE photodiodes is considerable wider and achieves 550 - 1000 nm. These photodiodes can be used in detection of very weak and very fast optical signals. Presently in the world, the studies are carried out on applying the avalanche photodiodes in detection of X radiation and in the scintillation detection of nuclear radiation.

Near Real-Time Monitoring of Forest Disturbance: A Multi-Sensor Remote Sensing Approach and Assessment Framework

NASA Astrophysics Data System (ADS)

Tang, Xiaojing

Fast and accurate monitoring of tropical forest disturbance is essential for understanding current patterns of deforestation as well as helping eliminate illegal logging. This dissertation explores the use of data from different satellites for near real-time monitoring of forest disturbance in tropical forests, including: development of new monitoring methods; development of new assessment methods; and assessment of the performance and operational readiness of existing methods. Current methods for accuracy assessment of remote sensing products do not address the priority of near real-time monitoring of detecting disturbance events as early as possible. I introduce a new assessment framework for near real-time products that focuses on the timing and the minimum detectable size of disturbance events. The new framework reveals the relationship between change detection accuracy and the time needed to identify events. In regions that are frequently cloudy, near real-time monitoring using data from a single sensor is difficult. This study extends the work by Xin et al. (2013) and develops a new time series method (Fusion2) based on fusion of Landsat and MODIS (Moderate Resolution Imaging Spectroradiometer) data. Results of three test sites in the Amazon Basin show that Fusion2 can detect 44.4% of the forest disturbance within 13 clear observations (82 days) after the initial disturbance. The smallest event detected by Fusion2 is 6.5 ha. Also, Fusion2 detects disturbance faster and has less commission error than more conventional methods. In a comparison of coarse resolution sensors, MODIS Terra and Aqua combined provides faster and more accurate detection of disturbance events than VIIRS (Visible Infrared Imaging Radiometer Suite) and MODIS single sensor data. The performance of near real-time monitoring using VIIRS is slightly worse than MODIS Terra but significantly better than MODIS Aqua. New monitoring methods developed in this dissertation provide forest protection organizations the capacity to monitor illegal logging events promptly. In the future, combining two Landsat and two Sentinel-2 satellites will provide global coverage at 30 m resolution every 4 days, and routine monitoring may be possible at high resolution. The methods and assessment framework developed in this dissertation are adaptable to newly available datasets.

Prognostic value of the immunocytochemical detection of extramural venous invasion in Dukes' C colorectal adenocarcinomas. A preliminary study.

PubMed Central

Lapertosa, G.; Baracchini, P.; Fulcheri, E.; Tanzi, R.

1989-01-01

In postsurgical staging of colorectal adenocarcinomas, it is sometimes difficult to determine the range of possible venous spread. Distinguishing between the extramural veins (especially when the neoplastic embolus takes up the whole lumen and the endothelium cannot be identified) and the smallest extramural lymph nodes (when they are completely replaced by metastatic carcinoma, leaving the capsule alone) is also difficult. This work proposes a more precise definition of true venous invasion to improve histopathologic staging. Immunohistochemical techniques employing commercial antibodies against Factor VIII RAG, with and without enzymatic digestion, and UEA I lectin for residual endothelium detection, were applied, as well as antibodies against vimentin, desmin, and alpha sm-1 actin to detect wall components. The immunohistochemical evaluation of colorectal adenocarcinomas, in particular by anti-alpha sm-1 actin antibodies, permitted a reliable morphologic distinction of the true venous invasion. This factor proved to be relevant for survival rate prediction. Images Figure 1 Figure 2 PMID:2817085

Applications of gold nanoparticles in virus detection

PubMed Central

Draz, Mohamed Shehata; Shafiee, Hadi

2018-01-01

Viruses are the smallest known microbes, yet they cause the most significant losses in human health. Most of the time, the best-known cure for viruses is the innate immunological defense system of the host; otherwise, the initial prevention of viral infection is the only alternative. Therefore, diagnosis is the primary strategy toward the overarching goal of virus control and elimination. The introduction of a new class of nanoscale materials with multiple unique properties and functions has sparked a series of breakthrough applications. Gold nanoparticles (AuNPs) are widely reported to guide an impressive resurgence in biomedical and diagnostic applications. Here, we review the applications of AuNPs in virus testing and detection. The developed AuNP-based detection techniques are reported for various groups of clinically relevant viruses with a special focus on the applied types of bio-AuNP hybrid structures, virus detection targets, and assay modalities and formats. We pay particular attention to highlighting the functional role and activity of each core Au nanostructure and the resultant detection improvements in terms of sensitivity, detection range, and time. In addition, we provide a general summary of the contributions of AuNPs to the mainstream methods of virus detection, technical measures, and recommendations required in guidance toward commercial in-field applications. PMID:29556369

National health expenditures, 1984

PubMed Central

Levit, Katharine R.; Lazenby, Helen; Waldo, Daniel R.; Davidoff, Lawrence M.

1985-01-01

Growth in health care expenditures slowed to 9.1 percent in 1984, the smallest increase in expenditures in 19 years. Economic forces and emerging structural changes within the health sector played a role in slowing growth. Of the $1,580 per person spent for health care in 1984, 41 percent was financed by public programs; 31 percent by private health insurance; and the remainder by other private sources. Together, Medicare and Medicaid accounted for 27 percent of all health spending. PMID:10311395

Results of a protocol of transfusion threshold and surgical technique on transfusion requirements in burn patients.

PubMed

O'Mara, Michael S; Hayetian, Fernando; Slater, Harvey; Goldfarb, I William; Tolchin, Eric; Caushaj, Philip F

2005-08-01

Blood loss and high rates of transfusion in burn centers remains an area of ongoing concern. Blood use brings the risk of infection, adverse reaction, and immunosuppression. A protocol to reduce blood loss and blood use was implemented. Analysis included 3-year periods before and after institution of the protocol. All patients were transfused for a hemoglobin below 8.0 gm/dL. Operations per admission did not change during the two time periods (0.78 in each). Overall units transfused per operation decreased from 1.56+/-0.06 to 1.25+/-0.14 units after instituting the protocol (p<0.05). Also, units transfused per admission decreased from 1.21+/-0.15 to 0.96+/-0.06 units of blood (p<0.05). This was noticed particularly in burns of less than 20% surface area, declining from 386 to 46 units after protocol institution, from 0.37 to 0.04 units per admission, and from 0.79 to 0.08 units per operation in this group of smallest burns. There was no change noted in the larger burns. This study suggests that a defined protocol of hemostasis, technique, and transfusion trigger should be implemented in the process of burn excision and grafting. This will help especially those patients with the smallest burns, essentially eliminating transfusion need in that group.

Novel Synechococcus Genomes Reconstructed from Freshwater Reservoirs

PubMed Central

Cabello-Yeves, Pedro J.; Haro-Moreno, Jose M.; Martin-Cuadrado, Ana-Belen; Ghai, Rohit; Picazo, Antonio; Camacho, Antonio; Rodriguez-Valera, Francisco

2017-01-01

Freshwater picocyanobacteria including Synechococcus remain poorly studied at the genomic level, compared to their marine representatives. Here, using a metagenomic assembly approach we discovered two novel Synechococcus sp. genomes from two freshwater reservoirs Tous and Lake Lanier, both sharing 96% average nucleotide identity and displaying high abundance levels in these two lakes located at similar altitudes and temperate latitudes. These new genomes have the smallest estimated size (2.2 Mb) and average intergenic spacer length (20 bp) of any previously sequenced freshwater Synechococcus, which may contribute to their success in oligotrophic freshwater systems. Fluorescent in situ hybridization confirmed that Synechococcus sp. Tous comprises small cells (0.987 ± 0.139 μm length, 0.723 ± 0.119 μm width) that amount to 90% of the picocyanobacteria in Tous. They appear together in a phylogenomic tree with Synechococcus sp. RCC307 strain, the main representative of sub-cluster 5.3 that has itself one of the smallest marine Synechococcus genomes. We detected a type II phycobilisome (PBS) gene cluster in both genomes, which suggests that they belong to a phycoerythrin-rich pink low-light ecotype. The decrease of acidic proteins and the higher content of basic transporters and membrane proteins in the novel Synechococcus genomes, compared to marine representatives, support their freshwater specialization. A sulfate Cys transporter which is absent in marine but has been identified in many freshwater cyanobacteria was also detected in Synechococcus sp. Tous. The RuBisCo subunits from this microbe are phylogenetically close to the freshwater amoeba Paulinella chromatophora symbiont, hinting to a freshwater origin of the carboxysome operon of this protist. The novel genomes enlarge the known diversity of freshwater Synechococcus and improve the overall knowledge of the relationships among members of this genus at large. PMID:28680419

Occurrence and core-envelope structure of 1-4× Earth-size planets around Sun-like stars.

PubMed

Marcy, Geoffrey W; Weiss, Lauren M; Petigura, Erik A; Isaacson, Howard; Howard, Andrew W; Buchhave, Lars A

2014-09-02

Small planets, 1-4× the size of Earth, are extremely common around Sun-like stars, and surprisingly so, as they are missing in our solar system. Recent detections have yielded enough information about this class of exoplanets to begin characterizing their occurrence rates, orbits, masses, densities, and internal structures. The Kepler mission finds the smallest planets to be most common, as 26% of Sun-like stars have small, 1-2 R⊕ planets with orbital periods under 100 d, and 11% have 1-2 R⊕ planets that receive 1-4× the incident stellar flux that warms our Earth. These Earth-size planets are sprinkled uniformly with orbital distance (logarithmically) out to 0.4 the Earth-Sun distance, and probably beyond. Mass measurements for 33 transiting planets of 1-4 R⊕ show that the smallest of them, R < 1.5 R⊕, have the density expected for rocky planets. Their densities increase with increasing radius, likely caused by gravitational compression. Including solar system planets yields a relation: ρ = 2:32 + 3:19 R=R ⊕ [g cm(-3)]. Larger planets, in the radius range 1.5-4.0 R⊕, have densities that decline with increasing radius, revealing increasing amounts of low-density material (H and He or ices) in an envelope surrounding a rocky core, befitting the appellation ''mini-Neptunes.'' The gas giant planets occur preferentially around stars that are rich in heavy elements, while rocky planets occur around stars having a range of heavy element abundances. Defining habitable zones remains difficult, without benefit of either detections of life elsewhere or an understanding of life's biochemical origins.

Occurrence and core-envelope structure of 1–4× Earth-size planets around Sun-like stars

PubMed Central

Marcy, Geoffrey W.; Weiss, Lauren M.; Petigura, Erik A.; Isaacson, Howard; Howard, Andrew W.; Buchhave, Lars A.

2014-01-01

Small planets, 1–4× the size of Earth, are extremely common around Sun-like stars, and surprisingly so, as they are missing in our solar system. Recent detections have yielded enough information about this class of exoplanets to begin characterizing their occurrence rates, orbits, masses, densities, and internal structures. The Kepler mission finds the smallest planets to be most common, as 26% of Sun-like stars have small, 1–2 R⊕ planets with orbital periods under 100 d, and 11% have 1–2 R⊕ planets that receive 1–4× the incident stellar flux that warms our Earth. These Earth-size planets are sprinkled uniformly with orbital distance (logarithmically) out to 0.4 the Earth–Sun distance, and probably beyond. Mass measurements for 33 transiting planets of 1–4 R⊕ show that the smallest of them, R < 1.5 R⊕, have the density expected for rocky planets. Their densities increase with increasing radius, likely caused by gravitational compression. Including solar system planets yields a relation: ρ=2.32+3.19R/R⊕ [g cm−3]. Larger planets, in the radius range 1.5–4.0 R⊕, have densities that decline with increasing radius, revealing increasing amounts of low-density material (H and He or ices) in an envelope surrounding a rocky core, befitting the appellation ‘‘mini-Neptunes.’’ The gas giant planets occur preferentially around stars that are rich in heavy elements, while rocky planets occur around stars having a range of heavy element abundances. Defining habitable zones remains difficult, without benefit of either detections of life elsewhere or an understanding of life’s biochemical origins. PMID:24912169

Distribution pattern of public transport passenger in Yogyakarta, Indonesia

NASA Astrophysics Data System (ADS)

Narendra, Alfa; Malkhamah, Siti; Sopha, Bertha Maya

2018-03-01

The arrival and departure distribution pattern of Trans Jogja bus passenger is one of the fundamental model for simulation. The purpose of this paper is to build models of passengers flows. This research used passengers data from January to May 2014. There is no policy that change the operation system affecting the nature of this pattern nowadays. The roads, buses, land uses, schedule, and people are relatively still the same. The data then categorized based on the direction, days, and location. Moreover, each category was fitted into some well-known discrete distributions. Those distributions are compared based on its AIC value and BIC. The chosen distribution model has the smallest AIC and BIC value and the negative binomial distribution found has the smallest AIC and BIC value. Probability mass function (PMF) plots of those models were compared to draw generic model from each categorical negative binomial distribution models. The value of accepted generic negative binomial distribution is 0.7064 and 1.4504 of mu. The minimum and maximum passenger vector value of distribution are is 0 and 41.

Morphological changes in ultrafast laser ablation plumes with varying spot size

DOE PAGES

Harilal, S. S.; Diwakar, P. K.; Polek, M. P.; ...

2015-06-04

We investigated the role of spot size on plume morphology during ultrafast laser ablation of metal targets. Our results show that the spatial features of fs LA plumes are strongly dependent on the focal spot size. Two-dimensional self-emission images showed that the shape of the ultrafast laser ablation plumes changes from spherical to cylindrical with an increasing spot size from 100 to 600 μm. The changes in plume morphology and internal structures are related to ion emission dynamics from the plasma, where broader angular ion distribution and faster ions are noticed for the smallest spot size used. The present resultsmore » clearly show that the morphological changes in the plume with spot size are independent of laser pulse width.« less

The smallest natural high-active luciferase: cloning and characterization of novel 16.5-kDa luciferase from copepod Metridia longa.

PubMed

Markova, Svetlana V; Larionova, Marina D; Burakova, Ludmila P; Vysotski, Eugene S

2015-01-30

Coelenterazine-dependent copepod luciferases containing natural signal peptide for secretion are a very convenient analytical tool as they enable monitoring of intracellular events with high sensitivity, without destroying cells or tissues. This property is well suited for application in biomedical research and development of cell-based assays for high throughput screening. We report the cloning of cDNA gene encoding a novel secreted non-allelic 16.5-kDa isoform (MLuc7) of Metridia longa luciferase, which, in fact, is the smallest natural luciferase of known for today. Despite the small size, isoform contains 10 conservative Cys residues suggesting the presence of up to 5 SS bonds. This hampers the efficient production of functionally active recombinant luciferase in bacterial expression systems. With the use of the baculovirus expression system, we produced substantial amounts of the proper folded MLuc7 luciferase with a yield of ∼3 mg/L of a high purity protein. We demonstrate that MLuc7 produced in insect cells is highly active and extremely thermostable, and is well suited as a secreted reporter when expressed in mammalian cells ensuring higher sensitivity of detection as compared to another Metridia luciferase isoform (MLuc164) which is widely employed in real-time imaging. Copyright © 2014 Elsevier Inc. All rights reserved.

[Detection and Analysis of Human Parainfluenza Virus Infection in Hospitalized Adults with Acute Respiratory Tract Infections].

PubMed

Li, Xing-Qiao; Liu, Xue-Wei; Zhou, Tao; Pei, Xiao-Fang

2017-11-01

To investigate the prevalence and gene characteristics of different groups of human parainfluenza virus (HPIV) infection in hospitalized adults with acute respiratory tract infections (ARI). RT-PCR was used to detect HPIV hemagglutinin (HA) DNA,which was extracted from sputum samples of 1 039 adult patients with ARI from March,2014 to June,2016. The HA gene amplified from randomly selected positive samples were sequenced to analyze the homology and variation. 10.6% (110/1 039) of these samples were positive for HPIV,including 8 cases of HPIV-1,22 cases of HPIV-2,46 cases of HPIV-3 and 34 cases of HPIV-4. Detectable rate varied among different groups of HPIV according to seasons of the year and ages of patients. No significant differences were found between the positive samples and the reference sequences. Compared with different reference strains of different regions,the genetic distance of nucleotide is the smallest between the strains tested in this study and the reference strains of other provinces and cities in China. In Chengdu region,HPIV virus is highly detected in ARI,all subtypes were detected with HPIV-3 being the main subtype.

Ultrasensitive Detection of Ricin Toxin in Multiple Sample Matrixes Using Single-Domain Antibodies.

PubMed

Gaylord, Shonda T; Dinh, Trinh L; Goldman, Ellen R; Anderson, George P; Ngan, Kevin C; Walt, David R

2015-07-07

Ricin is an extremely potent ribosomal inactivating protein listed as a Category B select agent. Although ricin intoxication is not transmittable from person to person, even a single ricin molecule can lead to cell necrosis because it inactivates 1500 ribosomes/min. Since there is currently no vaccine or therapeutic treatment for ricin intoxication, ultrasensitive analytical assays capable of detecting ricin in a variety of matrixes are urgently needed to limit exposure to individuals as well as communities. In this paper, we present the development and application of a single-molecule array (Simoa) for the detection of ricin toxin in human urine and serum. Single-domain antibodies (sdAbs), among the smallest engineered binding fragments, were chemically coupled to the surface of paramagnetic beads for the sensitive detection of ricin toxin. The Simoa was able to detect ricin at levels of 10 fg/mL, 100 fg/mL, and 1 pg/mL in buffer, urine and serum, respectively, in a fraction of the assay time need using immuno-polymerase chain reaction (IPCR). Using a fully automated state-of-the-art platform, the Simoa HD-1 analyzer, the assay time was reduced to 64 min.

Simple shoulder test and Oxford Shoulder Score: Persian translation and cross-cultural validation.

PubMed

Naghdi, Soofia; Nakhostin Ansari, Noureddin; Rustaie, Nilufar; Akbari, Mohammad; Ebadi, Safoora; Senobari, Maryam; Hasson, Scott

2015-12-01

To translate, culturally adapt, and validate the simple shoulder test (SST) and Oxford Shoulder Score (OSS) into Persian language using a cross-sectional and prospective cohort design. A standard forward and backward translation was followed to culturally adapt the SST and the OSS into Persian language. Psychometric properties of floor and ceiling effects, construct convergent validity, discriminant validity, internal consistency reliability, test-retest reliability, standard error of the measurement (SEM), smallest detectable change (SDC), and factor structure were determined. One hundred patients with shoulder disorders and 50 healthy subjects participated in the study. The PSST and the POSS showed no missing responses. No floor or ceiling effects were observed. Both the PSST and POSS detected differences between patients and healthy subjects supporting their discriminant validity. Construct convergent validity was confirmed by a very good correlation between the PSST and POSS (r = 0.68). There was high internal consistency for both the PSST (α = 0.73) and the POSS (α = 0.91 and 0.92). Test-retest reliability with 1-week interval was excellent (ICCagreement = 0.94 for PSST and 0.90 for POSS). Factor analyses demonstrated a three-factor solution for the PSST (49.7 % of variance) and a two-factor solution for the POSS (61.6 % of variance). The SEM/SDC was satisfactory for PSST (5.5/15.3) and POSS (6.8/18.8). The PSST and POSS are valid and reliable outcome measures for assessing functional limitations in Persian-speaking patients with shoulder disorders.

4p16.3 microdeletions and microduplications detected by chromosomal microarray analysis: New insights into mechanisms and critical regions.

PubMed

Bi, Weimin; Cheung, Sau-Wai; Breman, Amy M; Bacino, Carlos A

2016-10-01

Deletions in the 4p16.3 region cause Wolf-Hirschhorn syndrome, a well known contiguous microdeletion syndrome with the critical region for common phenotype mapped in WHSCR2. Recently, duplications in 4p16.3 were reported in three patients with developmental delay and dysmorphic features. Through chromosomal microarray analysis, we identified 156 patients with a deletion (n = 109) or duplication (n = 47) in 4p16.3 out of approximately 60,000 patients analyzed by Baylor Miraca Genetics Laboratories. Seventy-five of the postnatally detected deletions encompassed the entire critical region, 32 (43%) of which were associated with other chromosome rearrangements, including six patients (8%) that had a duplication adjacent to the terminal deletion. Our data indicate that Wolf-Hirschhorn syndrome deletions with an adjacent duplication occur at a higher frequency than previously appreciated. Pure deletions (n = 14) or duplications (n = 15) without other copy number changes distal to or inside the WHSCR2 were identified for mapping of critical regions. Our data suggest that deletion of the segment from 0.6 to 0.9 Mb from the terminus of 4p causes a seizure phenotype and duplications of a region distal to the previously defined smallest region of overlap for 4p16.3 microduplication syndrome are associated with neurodevelopmental problems. We detected seven Wolf-Hirschhorn syndrome deletions and one 4p16.3 duplication prenatally; all of the seven are either >8 Mb in size and/or associated with large duplications. In conclusion, our study provides deeper insight into the molecular mechanisms, the critical regions and effective prenatal diagnosis for 4p16.3 deletions/ duplications. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Intrarater reliability of the Humac NORM isokinetic dynamometer for strength measurements of the knee and shoulder muscles.

PubMed

Habets, Bas; Staal, J Bart; Tijssen, Marsha; van Cingel, Robert

2018-01-10

To determine the intrarater reliability of the Humac NORM isokinetic dynamometer for concentric and eccentric strength tests of knee and shoulder muscles. 54 participants (50% female, average age 20.9 ± 3.1 years) performed concentric and eccentric strength measures of the knee extensors and flexors, and the shoulder internal and external rotators on two different Humac NORM isokinetic dynamometers, which were situated at two different centers. The knee extensors and flexors were tested concentrically at 60° and 180°/s, and eccentrically at 60° s. Concentric strength of the shoulder internal and external rotators, and eccentric strength of the external rotators were measured at 60° and 120°/s. We calculated intraclass correlation coefficients (ICCs), standard error of measurement, standard error of measurement expressed as a %, and the smallest detectable change to determine reliability and measurement error. ICCs for the knee tests ranged from 0.74 to 0.89, whereas ICC values for the shoulder tests ranged from 0.72 to 0.94. Measurement error was highest for the concentric test of the knee extensors and lowest for the concentric test of shoulder external rotators.

Accumulation of Inertial Sensory Information in the Perception of Whole Body Yaw Rotation.

PubMed

Nesti, Alessandro; de Winkel, Ksander; Bülthoff, Heinrich H

2017-01-01

While moving through the environment, our central nervous system accumulates sensory information over time to provide an estimate of our self-motion, allowing for completing crucial tasks such as maintaining balance. However, little is known on how the duration of the motion stimuli influences our performances in a self-motion discrimination task. Here we study the human ability to discriminate intensities of sinusoidal (0.5 Hz) self-rotations around the vertical axis (yaw) for four different stimulus durations (1, 2, 3 and 5 s) in darkness. In a typical trial, participants experienced two consecutive rotations of equal duration and different peak amplitude, and reported the one perceived as stronger. For each stimulus duration, we determined the smallest detectable change in stimulus intensity (differential threshold) for a reference velocity of 15 deg/s. Results indicate that differential thresholds decrease with stimulus duration and asymptotically converge to a constant, positive value. This suggests that the central nervous system accumulates sensory information on self-motion over time, resulting in improved discrimination performances. Observed trends in differential thresholds are consistent with predictions based on a drift diffusion model with leaky integration of sensory evidence.

The Depth of Ice Inside the Smallest Cold-Traps on Mercury: Implications for Age and Origin

NASA Astrophysics Data System (ADS)

Rubanenko, L.; Mazarico, E.; Neumann, G. A.; Paige, D. A.

2018-05-01

We use Mercury Laser Altimeter data and an illumination model to constrain the depth of the smallest ice deposits on Mercury. By comparing this depth to modeled gardening rates, we estimate the age and delivery method of this ice.

Five-Kilometers Time Trial: Preliminary Validation of a Short Test for Cycling Performance Evaluation.

PubMed

Dantas, Jose Luiz; Pereira, Gleber; Nakamura, Fabio Yuzo

2015-09-01

The five-kilometer time trial (TT5km) has been used to assess aerobic endurance performance without further investigation of its validity. This study aimed to perform a preliminary validation of the TT5km to rank well-trained cyclists based on aerobic endurance fitness and assess changes of the aerobic endurance performance. After the incremental test, 20 cyclists (age = 31.3 ± 7.9 years; body mass index = 22.7 ± 1.5 kg/m(2); maximal aerobic power = 360.5 ± 49.5 W) performed the TT5km twice, collecting performance (time to complete, absolute and relative power output, average speed) and physiological responses (heart rate and electromyography activity). The validation criteria were pacing strategy, absolute and relative reliability, validity, and sensitivity. Sensitivity index was obtained from the ratio between the smallest worthwhile change and typical error. The TT5km showed high absolute (coefficient of variation < 3%) and relative (intraclass coefficient correlation > 0.95) reliability of performance variables, whereas it presented low reliability of physiological responses. The TT5km performance variables were highly correlated with the aerobic endurance indices obtained from incremental test (r > 0.70). These variables showed adequate sensitivity index (> 1). TT5km is a valid test to rank the aerobic endurance fitness of well-trained cyclists and to differentiate changes on aerobic endurance performance. Coaches can detect performance changes through either absolute (± 17.7 W) or relative power output (± 0.3 W.kg(-1)), the time to complete the test (± 13.4 s) and the average speed (± 1.0 km.h(-1)). Furthermore, TT5km performance can also be used to rank the athletes according to their aerobic endurance fitness.

Evaluation of the internal and external responsiveness of the Pressure Ulcer Scale for Healing (PUSH) tool for assessing acute and chronic wounds.

PubMed

Choi, Edmond P H; Chin, Weng Yee; Wan, Eric Y F; Lam, Cindy L K

2016-05-01

To examine the internal and external responsiveness of the Pressure Ulcer Scale for Healing (PUSH) tool for assessing the healing progress in acute and chronic wounds. It is important to establish the responsiveness of instruments used in conducting wound care assessments to ensure that they are able to capture changes in wound healing accurately over time. Prospective longitudinal observational study. The key study instrument was the PUSH tool. Internal responsiveness was assessed using paired t-testing and effect size statistics. External responsiveness was assessed using multiple linear regression. All new patients with at least one eligible acute or chronic wound, enrolled in the Nurse and Allied Health Clinic-Wound Care programme between 1 December 2012 - 31 March 2013 were included for analysis (N = 541). Overall, the PUSH tool was able to detect statistically significant changes in wound healing between baseline and discharge. The effect size statistics were large. The internal responsiveness of the PUSH tool was confirmed in patients with a variety of different wound types including venous ulcers, pressure ulcers, neuropathic ulcers, burns and scalds, skin tears, surgical wounds and traumatic wounds. After controlling for age, gender and wound type, subjects in the 'wound improved but not healed' group had a smaller change in PUSH scores than those in the 'wound healed' group. Subjects in the 'wound static or worsened' group had the smallest change in PUSH scores. The external responsiveness was confirmed. The internal and external responsiveness of the PUSH tool confirmed that it can be used to track the healing progress of both acute and chronic wounds. © 2016 The Authors. Journal of Advanced Nursing Published by John Wiley & Sons Ltd.

Pioneering Mars: Turning the Red Planet Green with Earth's Smallest Settlers

ERIC Educational Resources Information Center

Cwikla, Julie; Milroy, Scott; Reider, David; Skelton, Tara

2014-01-01

Pioneering Mars: Turning the Red Planet Green with the Earth's Smallest Settlers (http://pioneeringmars.org) provides a partnership model for STEM (science, technology, engineering, and mathematics) learning that brings university scientists together with high school students to investigate whether cyanobacteria from Antarctica could survive on…

Incidence of climate on common frog breeding: Long-term and short-term changes

NASA Astrophysics Data System (ADS)

Neveu, André

2009-09-01

In Brittany (northwest France), the climate is showing a trend toward warming. This change is increasingly suspected to have a role in driving amphibian decline, but it is very difficult to determine at what level the climate affects the future of species. Recently, some studies have detected some direct effects on breeding phenology and indirect effects on energy allocation. The present study explores some of these effects on the common frog ( Rana temporaria) from 1984 to 2007. The results show two trends: a long-term change in breeding activities and a short-term influence due to the 2003 climatic anomaly. For the period of study, the start of egg-laying shows a precocity that was correlated with thermal conditions during the preceding 40 days as well as milder springs during the previous year. This degree of precocity is currently the highest found in Europe (+26.6 days). As a result of the 2003 heat wave, the clutch mean fecundity in 2004 was smaller than for other years, the fecundity rates were reduced and abortions were numerous (unlike other years). Moreover, young females were the smallest observed in recent years and some females seemed to exhibit a trade-off between fecundity and growth. Before or after egg-laying, female body condition and mean weight of mature ovules were both lower. The year 2005 appears as a transition period before the recovery in 2006-2007. The results show that climate warming endangers the vital rates of the common frog, while the 2003 climatic events seem more detrimental than the long-term warming trend.

Identification of a novel gammaherpesvirus associated with (muco)cutaneous lesions in harbour porpoises (Phocoena phocoena).

PubMed

van Beurden, Steven J; IJsseldijk, Lonneke L; Ordonez, Soledad R; Förster, Christine; de Vrieze, Geert; Gröne, Andrea; Verheije, M Hélène; Kik, Marja

2015-12-01

Herpesviruses infect a wide range of vertebrates, including toothed whales of the order Cetacea. One of the smallest toothed whales is the harbour porpoise (Phocoena phocoena), which is widespread in the coastal waters of the northern hemisphere, including the North Sea. Here, we describe the detection and phylogenetic analysis of a novel gammaherpesvirus associated with mucocutaneous and skin lesions in stranded harbour porpoises along the Dutch coast, tentatively designated phocoenid herpesvirus 1 (PhoHV1). Phylogenetically, PhoHV1 forms a monophyletic clade with all other gammaherpesviruses described in toothed whales (Odontoceti) to date, suggesting a common evolutionary origin.

Standardized strapdown inertial component modularity study, volume 2

NASA Technical Reports Server (NTRS)

Feldman, J.

1974-01-01

To obtain cost effective strapdown navigation, guidance and stabilization systems to meet anticipated future needs a standardized modularized strapdown system concept is proposed. Three performance classes, high, medium and low, are suggested to meet the range of applications. Candidate inertial instruments are selected and analyzed for interface compatibility. Electronic packaging and processing, materials and thermal considerations applying to the three classes are discussed and recommendations advanced. Opportunities for automatic fault detection and redundancy are presented. The smallest gyro and accelerometer modules are projected as requiring a volume of 26 cubic inches and 23.6 cubic inches, respectively. Corresponding power dissipation is projected as 5 watts, and 2.6 watts respectively.

Measurement of optical coupling between adjacent bi-material microcantilevers.

PubMed

Canetta, Carlo; Narayanaswamy, Arvind

2013-10-01

Low thermal conductance bi-material microcantilevers are fabricated with a pad area near the free end to accommodate a focused laser spot. A pair of such cantilevers are proposed as a configuration for measuring thermal conductance of a nanostructure suspended between the two. We determine the resolution of such a device by measuring the stray conductance it would detect in the absence of any nanostructure. Stray conductance, primarily due to optical coupling, is measured for cantilevers with varying pad size and found to be as low as 0.05 nW K(-1), with cantilevers with larger pad size yielding the smallest stray conductance.

Effects of geolocators on hatching success, return rates, breeding movements, and change in body mass in 16 species of Arctic-breeding shorebirds

USGS Publications Warehouse

Weiser, Emily; Lanctot, Richard B.; Brown, Stephen C.; Alves, José A.; Battley, Phil F.; Bentzen, Rebecca L.; Bety, Joel; Bishop, Mary Anne; Boldenow, Megan; Bollache, Loic; Casler, Bruce; Christie, Maureen; Coleman, Jonathan T.; Conklin, Jesse R.; English, Willow B.; Gates, H. River; Gilg, Olivier; Giroux, Marie-Andree; Gosbell, Ken; Hassell, Chris J.; Helmericks, Jim; Johnson, Andrew; Katrinardottir, Borgny; Koivula, Kari; Kwon, Eunbi; Lamarre, Jean-Francois; Lang, Johannes; Lank, David B.; Lecomte, Nicolas; Liebezeit, Joseph R.; Loverti, Vanessa; McKinnon, Laura; Minton, Clive; Mizrahi, David S.; Nol, Erica; Pakanen, Veli-Matti; Perz, Johanna; Porter, Ron; Rausch, Jennie; Reneerkens, Jeroen; Ronka, Nelli; Saalfeld, Sarah T.; Senner, Nathan R.; Sittler, Benoit; Smith, Paul A.; Sowl, Kristine M.; Taylor, Audrey; Ward, David H.; Yezerinac, Stephen; Sandercock, Brett K.

2016-01-01

Negative effects of geolocators occurred only for three of the smallest species in our dataset, but were substantial when present. Future studies could mitigate impacts of tags by reducing protruding parts and minimizing use of additional markers. Investigators could maximize recovery of tags by strategically deploying geolocators on males, previously marked individuals, and successful breeders, though targeting subsets of a population could bias the resulting migratory movement data in some species.

Development of array piezoelectric fingers towards in vivo breast tumor detection

NASA Astrophysics Data System (ADS)

Xu, Xin; Chung, Youngsoo; Brooks, Ari D.; Shih, Wei-Heng; Shih, Wan Y.

2016-12-01

We have investigated the development of a handheld 4 × 1 piezoelectric finger (PEF) array breast tumor detector system towards in vivo patient testing, particularly, on how the duration of the DC applied voltage, the depression depth of the handheld unit, and breast density affect the PEF detection sensitivity on 40 patients. The tests were blinded and carried out in four phases: with DC voltage durations 5, 3, 2, to 0.8 s corresponding to scanning a quadrant, a half, a whole breast, and both breasts within 30 min, respectively. The results showed that PEF detection sensitivity was unaffected by shortening the applied voltage duration from 5 to 0.8 s nor was it affected by increasing the depression depth from 2 to 6 mm. Over the 40 patients, PEF detected 46 of the 48 lesions (46/48)—with the smallest lesion detected being 5 mm in size. Of 28 patients (some have more than one lesion) with mammography records, PEF detected 31/33 of all lesions (94%) and 14/15 of malignant lesions (93%), while mammography detected 30/33 of all lesions (91%) and 12/15 of malignant lesions (80%), indicating that PEF could detect malignant lesions not detectable by mammography without significantly increasing false positives. PEF's detection sensitivity is also shown to be independent of breast density, suggesting that PEF could be a potential tool for detecting breast cancer in young women and women with dense breasts.

Software thresholds alter the bias of actigraphy for monitoring sleep in team-sport athletes.

PubMed

Fuller, Kate L; Juliff, Laura; Gore, Christopher J; Peiffer, Jeremiah J; Halson, Shona L

2017-08-01

Actical ® actigraphy is commonly used to monitor athlete sleep. The proprietary software, called Actiware ® , processes data with three different sleep-wake thresholds (Low, Medium or High), but there is no standardisation regarding their use. The purpose of this study was to examine validity and bias of the sleep-wake thresholds for processing Actical ® sleep data in team sport athletes. Validation study comparing actigraph against accepted gold standard polysomnography (PSG). Sixty seven nights of sleep were recorded simultaneously with polysomnography and Actical ® devices. Individual night data was compared across five sleep measures for each sleep-wake threshold using Actiware ® software. Accuracy of each sleep-wake threshold compared with PSG was evaluated from mean bias with 95% confidence limits, Pearson moment-product correlation and associated standard error of estimate. The Medium threshold generated the smallest mean bias compared with polysomnography for total sleep time (8.5min), sleep efficiency (1.8%) and wake after sleep onset (-4.1min); whereas the Low threshold had the smallest bias (7.5min) for wake bouts. Bias in sleep onset latency was the same across thresholds (-9.5min). The standard error of the estimate was similar across all thresholds; total sleep time ∼25min, sleep efficiency ∼4.5%, wake after sleep onset ∼21min, and wake bouts ∼8 counts. Sleep parameters measured by the Actical ® device are greatly influenced by the sleep-wake threshold applied. In the present study the Medium threshold produced the smallest bias for most parameters compared with PSG. Given the magnitude of measurement variability, confidence limits should be employed when interpreting changes in sleep parameters. Copyright © 2017 Sports Medicine Australia. All rights reserved.

Comparison of myelination between large and small pig fetuses during late gestation

USDA-ARS?s Scientific Manuscript database

We compared myelination of the cerebellum, brain stem, and spinal cord in the largest and smallest pig fetuses within a litter during late gestation. Gilts were killed on days 92, 100, and 110 of gestation and these neural tissues were obtained from the largest and smallest fetuses in each litter. M...

Modeling Occupancy of Hosts by Mistletoe Seeds after Accounting for Imperfect Detectability

PubMed Central

Fadini, Rodrigo F.; Cintra, Renato

2015-01-01

The detection of an organism in a given site is widely used as a state variable in many metapopulation and epidemiological studies. However, failure to detect the species does not necessarily mean that it is absent. Assessing detectability is important for occupancy (presence—absence) surveys; and identifying the factors reducing detectability may help improve survey precision and efficiency. A method was used to estimate the occupancy status of host trees colonized by mistletoe seeds of Psittacanthus plagiophyllus as a function of host covariates: host size and presence of mistletoe infections on the same or on the nearest neighboring host (the cashew tree Anacardium occidentale). The technique also evaluated the effect of taking detectability into account for estimating host occupancy by mistletoe seeds. Individual host trees were surveyed for presence of mistletoe seeds with the aid of two or three observers to estimate detectability and occupancy. Detectability was, on average, 17% higher in focal-host trees with infected neighbors, while decreased about 23 to 50% from smallest to largest hosts. The presence of mistletoe plants in the sample tree had negligible effect on detectability. Failure to detect hosts as occupied decreased occupancy by 2.5% on average, with maximum of 10% for large and isolated hosts. The method presented in this study has potential for use with metapopulation studies of mistletoes, especially those focusing on the seed stage, but also as improvement of accuracy in occupancy models estimates often used for metapopulation dynamics of tree-dwelling plants in general. PMID:25973754

Does the Location of Bruch's Membrane Opening Change Over Time? Longitudinal Analysis Using San Diego Automated Layer Segmentation Algorithm (SALSA).

PubMed

Belghith, Akram; Bowd, Christopher; Medeiros, Felipe A; Hammel, Naama; Yang, Zhiyong; Weinreb, Robert N; Zangwill, Linda M

2016-02-01

We determined if the Bruch's membrane opening (BMO) location changes over time in healthy eyes and eyes with progressing glaucoma, and validated an automated segmentation algorithm for identifying the BMO in Cirrus high-definition coherence tomography (HD-OCT) images. We followed 95 eyes (35 progressing glaucoma and 60 healthy) for an average of 3.7 ± 1.1 years. A stable group of 50 eyes had repeated tests over a short period. In each B-scan of the stable group, the BMO points were delineated manually and automatically to assess the reproducibility of both segmentation methods. Moreover, the BMO location variation over time was assessed longitudinally on the aligned images in 3D space point by point in x, y, and z directions. Mean visual field mean deviation at baseline of the progressing glaucoma group was -7.7 dB. Mixed-effects models revealed small nonsignificant changes in BMO location over time for all directions in healthy eyes (the smallest P value was 0.39) and in the progressing glaucoma eyes (the smallest P value was 0.30). In the stable group, the overall intervisit-intraclass correlation coefficient (ICC) and coefficient of variation (CV) were 98.4% and 2.1%, respectively, for the manual segmentation and 98.1% and 1.9%, respectively, for the automated algorithm. Bruch's membrane opening location was stable in normal and progressing glaucoma eyes with follow-up between 3 and 4 years indicating that it can be used as reference point in monitoring glaucoma progression. The BMO location estimation with Cirrus HD-OCT using manual and automated segmentation showed excellent reproducibility.

Reliability and Validity of a New Test of Agility and Skill for Female Amateur Soccer Players

PubMed Central

Kutlu, Mehmet; Yapici, Hakan; Yilmaz, Abdullah

2017-01-01

Abstract The aim of this study was to evaluate the Agility and Skill Test, which had been recently developed to assess agility and skill in female athletes. Following a 10 min warm-up, two trials to test the reliability and validity of the test were conducted one week apart. Measurements were collected to compare soccer players’ physical performance in a 20 m sprint, a T-Drill test, the Illinois Agility Run Test, change-of-direction and acceleration, as well as agility and skill. All tests were completed following the same order. Thirty-four amateur female soccer players were recruited (age = 20.8 ± 1.9 years; body height = 166 ± 6.9 cm; body mass = 55.5 ± 5.8 kg). To determine the reliability and usefulness of these tests, paired sample t-tests, intra-class correlation coefficients, typical error, coefficient of variation, and differences between the typical error and smallest worthwhile change statistics were computed. Test results showed no significant differences between the two sessions (p > 0.01). There were higher intra-class correlations between the test and retest values (r = 0.94–0.99) for all tests. Typical error values were below the smallest worthwhile change, indicating ‘good’ usefulness for these tests. A near perfect Pearson correlation between the Agility and Skill Test (r = 0.98) was found, and there were moderate-to-large levels of correlation between the Agility and Skill Test and other measures (r = 0.37 to r = 0.56). The results of this study suggest that the Agility and Skill Test is a reliable and valid test for female soccer players and has significant value for assessing the integrative agility and skill capability of soccer players. PMID:28469760

An experimental study on fatigue performance of cryogenic metallic materials for IMO type B tank

NASA Astrophysics Data System (ADS)

Lee, Jin-Sung; You, Won-Hyo; Yoo, Chang-Hyuk; Kim, Kyung-Su; Kim, Yooil

2013-12-01

Three materials SUS304, 9% Ni steel and Al 5083-O alloy, which are considered possible candidate for International Maritime Organization (IMO) type B Cargo Containment System, were studied. Monotonic tensile, fatigue, fatigue crack growth rate and Crack Tip Opening Displacement tests were carried out at room, intermediate low (-100 °C) and cryogenic (-163 °C) temperatures. The initial yield and tensile strengths of all materials tended to increase with decreasing temperature, whereas the change in elastic modulus was not as remarkable. The largest and smallest improvement ratio of the initial yield strengths due to a temperature reduction were observed in the SUS304 and Al 5083- O alloy, respectively. The fatigue strengths of the three materials increased with decreasing temperature. The largest increase in fatigue strength was observed in the Al 5083-O alloy, whereas the 9% Ni steel sample showed the smallest increase. In the fatigue crack growth rate test, SUS304 and Al 5083-O alloy showed a decrease in the crack propagation rate, due to decrease in temperature, but no visible improvement in da/dN was observed in the case of 9% Ni steel. In the Crack Tip Opening Displacement (CTOD) test, CTOD values were converted to critical crack length for the comparison with different thickness specimens. The critical crack length tended to decrease in the case of SUS304 and increase for the Al 5083-O alloy with decreasing temperature. In case of 9% Ni steel, change of critical crack length was not observed due to temperature decrease. In addition, the changing material properties according to the temperature of the LNG tank were analyzed according to the international code for the construction and equipment of ships carrying liquefied gases in bulk (IGC code) and the rules of classifications.

Time loss injuries compromise team success in Elite Rugby Union: a 7-year prospective study.

PubMed

Williams, Sean; Trewartha, Grant; Kemp, Simon P T; Brooks, John H M; Fuller, Colin W; Taylor, Aileen E; Cross, Matthew J; Stokes, Keith A

2016-06-01

A negative association between injuries and team success has been demonstrated in professional football, but the nature of this association in elite Rugby Union teams is currently unclear. To assess the association between injury burden measures and team success outcomes within professional Rugby Union teams. A seven-season prospective cohort design was used to record all time-loss injuries incurred by English Premiership players. Associations between team success measures (league points tally and Eurorugby Club Ranking (ECR)) and injury measures (injury burden and injury days per team-match) were modelled, both within (changes from season to season) and between (differences averaged over all seasons) teams. Thresholds for the smallest worthwhile change in league points tally and ECR were 3 points and 2.6%, respectively. Data from a total of 1462 players within 15 Premiership teams were included in the analysis. We found clear negative associations between injury measures and team success (70-100% likelihood), with the exception of between-team differences for injury days per team-match and ECR, which was unclear. A reduction in injury burden of 42 days (90% CI 30 to 70) per 1000 player hours (22% of mean injury burden) was associated with the smallest worthwhile change in league points tally. Clear negative associations were found between injury measures and team success, and moderate reductions in injury burden may have worthwhile effects on competition outcomes for professional Rugby Union teams. These findings may be useful when communicating the value of injury prevention initiatives within this elite sport setting. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Changes in bone resorption across the menopause transition: effects of reproductive hormones, body size, and ethnicity.

PubMed

Sowers, MaryFran R; Zheng, Huiyong; Greendale, Gail A; Neer, Robert M; Cauley, Jane A; Ellis, Jayne; Johnson, Sarah; Finkelstein, Joel S

2013-07-01

Our objective was to characterize changes in bone resorption in relation to the final menstrual period (FMP), reproductive hormones, body mass index (BMI), and ethnicity. Urinary type I collagen N-telopeptide (NTX), estradiol, and FSH levels were measured annually for up to 8 years spanning the menopause transition in 918 African American, Chinese, Japanese, or Caucasian women. Urinary NTX began to increase sharply about 2 years before the FMP, reaching its peak level about 1 to 1.5 years after the FMP. NTX levels declined modestly from 2 to 6 years after the FMP but remained about 20% higher than before the menopause transition. The sharp rise in FSH occurred in conjunction with a sharp decline in estradiol and shortly after FSH levels began increasing rapidly. The mean increase in urinary NTX across the menopause transition was greatest in women with BMI <25 kg/m² and smallest in women with BMI >30 kg/m². Increases in NTX were greatest in Japanese women and smallest in African Americans. These differences were attenuated, but not eliminated, when analyses were adjusted for covariates, particularly BMI. During the menopause transition, a decline in ovarian function beginning about 2 years before the FMP is followed by an increase in bone resorption and subsequently by bone loss. The magnitude of the increase in bone resorption is inversely associated with BMI. Ethnic differences in changes in bone resorption are attenuated, but not eliminated, by adjustment for BMI. Ethnic differences in BMI, and corresponding ethnic differences in bone resorption, appear to account for much of the ethnic variation in perimenopausal bone loss.

Predator size and the suitability of a common prey.

PubMed

Erickson, Kristin S; Morse, D H

1997-02-01

 Although a predator's mass should influence the suitability of its prey, this subject has received little direct attention. We studied the capture and processing of an abundant syrphid fly Toxomerus marginatus (c. 4 mg) by 0.6- to 40-mg juvenile crab spiders Misumena vatia (Thomisidae) to determine how profitability, relative profitability (profitability/predator mass), overall gain in mass, and relative gain in mass differed with predator mass, and whether foraging changed concurrently. In multi-prey experiments, the smallest successful spiders (0.6-3.0 mg) extracted less mass from flies, and did so more slowly, than large spiders. This gain was proportionately similar to that of 10- to 40-mg spiders with access to many Toxomerus. However, many small spiders failed to capture flies. When we gave spiders only a single Toxomerus, the smallest ones again extracted mass more slowly than the large ones and increased in mass less than the large ones, but increased in mass proportionately more than large ones. Relative gain in mass from a single prey decreased with increasing spider mass. Spiders larger than 10 mg all extracted similar amounts of mass from a single Toxomerus at similar rates, but varied in time spent between captures. Thus, Toxomerus changes with spider mass from a large, hard-to-capture bonanza to a small, easy-to-capture item of low per capita value. However, Toxomerus is common enough that large spiders can capture it en masse, thereby compensating for its decline in per capita value.

Size-related cytotoxicological aspects of polyvinylpyrrolidone-capped platinum nanoparticles.

PubMed

Buchtelova, Hana; Dostalova, Simona; Michalek, Petr; Krizkova, Sona; Strmiska, Vladislav; Kopel, Pavel; Hynek, David; Richtera, Lukas; Ridoskova, Andrea; Adam, Pavlina; Kynicky, Jindrich; Brtnicky, Martin; Heger, Zbynek; Adam, Vojtech

2017-07-01

The nanotechnological concept is based on size-dependent properties of particles in the 1-100 nm range. Nevertheless, the connection between their size and effect is still not clear. Thus, we focused on reductive colloidal synthesis, characterization and biological testing of Pt nanoparticles (PtNPs) capped with biocompatible polymer polyvinylpyrrolidone (PVP). Synthesized PtNPs were of 3 different primary sizes (approx. ∼10; ∼14 and > 20 nm) and demonstrated exceptional haemocompatibility. In vitro treatment of three different types of malignant cells (prostate - LNCaP, breast - MDA-MB-231 and neuroblastoma - GI-ME-N) revealed that even marginal differences in PtNPs diameter resulted in changes in their cytotoxicity. The highest cytotoxicity was observed using the smallest PtNPs-10, where 24IC 50 was lower (3.1-6.2 μg/mL) than for cisplatin (8.1-19.8 μg/mL). In contrast to MDA-MB-231 and LNCaP cells, in GI-ME-N cells PtNPs caused noticeable changes in their cellular structure without influencing their viability. Post-exposure analyses revealed that PtNPs-29 and PtNPs-40 were capable of forming considerably higher amount of reactive oxygen species with consequent stimulation of expression of metallothionein (MT1/2 and MT3), at both mRNA and protein level. Overall, our pilot study demonstrates that in the nanoscaled world even the smallest differences can have crucial biological effect. Copyright © 2017 Elsevier Ltd. All rights reserved.

Advanced illumination control algorithm for medical endoscopy applications

NASA Astrophysics Data System (ADS)

Sousa, Ricardo M.; Wäny, Martin; Santos, Pedro; Morgado-Dias, F.

2015-05-01

CMOS image sensor manufacturer, AWAIBA, is providing the world's smallest digital camera modules to the world market for minimally invasive surgery and one time use endoscopic equipment. Based on the world's smallest digital camera head and the evaluation board provided to it, the aim of this paper is to demonstrate an advanced fast response dynamic control algorithm of the illumination LED source coupled to the camera head, over the LED drivers embedded on the evaluation board. Cost efficient and small size endoscopic camera modules nowadays embed minimal size image sensors capable of not only adjusting gain and exposure time but also LED illumination with adjustable illumination power. The LED illumination power has to be dynamically adjusted while navigating the endoscope over changing illumination conditions of several orders of magnitude within fractions of the second to guarantee a smooth viewing experience. The algorithm is centered on the pixel analysis of selected ROIs enabling it to dynamically adjust the illumination intensity based on the measured pixel saturation level. The control core was developed in VHDL and tested in a laboratory environment over changing light conditions. The obtained results show that it is capable of achieving correction speeds under 1 s while maintaining a static error below 3% relative to the total number of pixels on the image. The result of this work will allow the integration of millimeter sized high brightness LED sources on minimal form factor cameras enabling its use in endoscopic surgical robotic or micro invasive surgery.

Producing Information for Corine Database by Using Classification Method: a Case Study of Sazlidere Basin, Istanbul

NASA Astrophysics Data System (ADS)

Sarıyılmaz, F. B.; Musaoğlu, N.; Uluğtekin, N.

2017-11-01

The Sazlidere Basin is located on the European side of Istanbul within the borders of Arnavutkoy and Basaksehir districts. The total area of the basin, which is largely located within the province of Arnavutkoy, is approximately 177 km2. The Sazlidere Basin is faced with intense urbanization pressures and land use / cover change due to the Northern Marmara Motorway, 3rd airport and Channel Istanbul Projects, which are planned to be realized in the Arnavutkoy region. Due to the mentioned projects, intense land use /cover changes occur in the basin. In this study, 2000 and 2012 dated LANDSAT images were supervised classified based on CORINE Land Cover first level to determine the land use/cover classes. As a result, four information classes were identified. These classes are water bodies, forest and semi-natural areas, agricultural areas and artificial surfaces. Accuracy analysis of the images were performed following the classification process. The supervised classified images that have the smallest mapping units 0.09 ha and 0.64 ha were generalized to be compatible with the CORINE Land Cover data. The image pixels have been rearranged by using the thematic pixel aggregation method as the smallest mapping unit is 25 ha. These results were compared with CORINE Land Cover 2000 and CORINE Land Cover 2012, which were obtained by digitizing land cover and land use classes on satellite images. It has been determined that the compared results are compatible with each other in terms of quality and quantity.

How Ebola impacts genetics of Western lowland gorilla populations.

PubMed

Le Gouar, Pascaline J; Vallet, Dominique; David, Laetitia; Bermejo, Magdalena; Gatti, Sylvain; Levréro, Florence; Petit, Eric J; Ménard, Nelly

2009-12-18

Emerging infectious diseases in wildlife are major threats for both human health and biodiversity conservation. Infectious diseases can have serious consequences for the genetic diversity of populations, which could enhance the species' extinction probability. The Ebola epizootic in western and central Africa induced more than 90% mortality in Western lowland gorilla population. Although mortality rates are very high, the impacts of Ebola on genetic diversity of Western lowland gorilla have never been assessed. We carried out long term studies of three populations of Western lowland gorilla in the Republic of the Congo (Odzala-Kokoua National Park, Lossi gorilla sanctuary both affected by Ebola and Lossi's periphery not affected). Using 17 microsatellite loci, we compared genetic diversity and structure of the populations and estimate their effective size before and after Ebola outbreaks. Despite the effective size decline in both populations, we did not detect loss in genetic diversity after the epizootic. We revealed temporal changes in allele frequencies in the smallest population. Immigration and short time elapsed since outbreaks could explain the conservation of genetic diversity after the demographic crash. Temporal changes in allele frequencies could not be explained by genetic drift or random sampling. Immigration from genetically differentiated populations and a non random mortality induced by Ebola, i.e., selective pressure and cost of sociality, are alternative hypotheses. Understanding the influence of Ebola on gorilla genetic dynamics is of paramount importance for human health, primate evolution and conservation biology.

19 CFR 122.48a - Electronic information for air cargo required in advance of arrival.

Code of Federal Regulations, 2012 CFR

2012-04-01

... data for incoming cargo that is listed in paragraph (d)(2) of this section: (i) An Automated Broker... based on the smallest external packing unit (M) (for example, 2 pallets containing 50 pieces each would... quantity based on the smallest external packing unit (M) (for example, 2 pallets containing 50 pieces each...

19 CFR 122.48a - Electronic information for air cargo required in advance of arrival.

Code of Federal Regulations, 2014 CFR

2014-04-01

... data for incoming cargo that is listed in paragraph (d)(2) of this section: (i) An Automated Broker... based on the smallest external packing unit (M) (for example, 2 pallets containing 50 pieces each would... quantity based on the smallest external packing unit (M) (for example, 2 pallets containing 50 pieces each...

19 CFR 122.48a - Electronic information for air cargo required in advance of arrival.

Code of Federal Regulations, 2013 CFR

2013-04-01

... data for incoming cargo that is listed in paragraph (d)(2) of this section: (i) An Automated Broker... based on the smallest external packing unit (M) (for example, 2 pallets containing 50 pieces each would... quantity based on the smallest external packing unit (M) (for example, 2 pallets containing 50 pieces each...

Adaptations to host infection and larval parasitism in Unionoida

Treesearch

Christopher M. Barnhart; Wendell R. Haag; William N. Roston

2008-01-01

Freshwater mussel larval parasitism of fish is unique among bivalves. The relationship is primarily phoretic rather than nutritive; only the smallest glochidia and the haustorial larva grow substantially while on the host. Growth of the smallest larvae suggests a lower functional size limit of -150 )um for the juvenile stage. Most Ambleminae, the most diverse North...

Ecological Guild Evolution and the Discovery of the World's Smallest Vertebrate

PubMed Central

Rittmeyer, Eric N.; Allison, Allen; Gründler, Michael C.; Thompson, Derrick K.; Austin, Christopher C.

2012-01-01

Living vertebrates vary drastically in body size, yet few taxa reach the extremely minute size of some frogs and teleost fish. Here we describe two new species of diminutive terrestrial frogs from the megadiverse hotspot island of New Guinea, one of which represents the smallest known vertebrate species, attaining an average body size of only 7.7 mm. Both new species are members of the recently described genus Paedophryne, the four species of which are all among the ten smallest known frog species, making Paedophryne the most diminutive genus of anurans. This discovery highlights intriguing ecological similarities among the numerous independent origins of diminutive anurans, suggesting that minute frogs are not mere oddities, but represent a previously unrecognized ecological guild. PMID:22253785

Resonant ultrasound spectroscopy and non-destructive testing

NASA Astrophysics Data System (ADS)

Migliori, A.; Darling, T. W.

The use of mechanical resonances to test properties of materials is perhaps older than the industrial revolution. Early documented cases of British railroad engineers tapping the wheels of a train and using the sound to detect cracks perhaps mark the first real use of resonances to test the integrity of high-performance alloys. Attempts were made in the following years to understand the resonances of solids mathematically, based on the shape and composition. But Nobel Laureate Lord Rayleigh best summarized the state of affairs in 1894, stating 'the problem has, for the most part, resisted attack'. More recently, modern computers and electronics have enabled Anderson and co-workers with their work on minerals, and our work at Los Alamos on new materials and manufactured components to advance the use of resonances to a precision non-destructive testing tool that makes anisotropic modulus measurements, defect detection and geometry error detection routine. The result is that resonances can achieve the highest absolute accuracy for any dynamic modulus measurement technique, can be used on the smallest samples, and can also enable detection of errors in certain classes of precision manufactured components faster and more accurately than any other technique.

Ground truth of (sub-)micrometre cometary dust - Results of MIDAS onboard Rosetta

NASA Astrophysics Data System (ADS)

Mannel, Thurid; Bentley, Mark; Schmied, Roland; Torkar, Klaus; Jeszenszky, Harald; Romsted, Jens; Levasseur-Regourd, A.; Weber, Iris; Jessberger, Elmar K.; Ehrenfreund, Pascale; Köberl, Christian; Havnes, Ove

2016-10-01

The investigation of comet 67P by Rosetta has allowed the comprehensive characterisation of pristine cometary dust particles ejected from the nucleus. Flying alongside the comet at distances as small as a few kilometres, and with a relative velocity of only centimetres per second, the Rosetta payload sampled almost unaltered dust. A key instrument to study this dust was MIDAS (the Micro-Imaging Dust Analysis System), a dedicated atomic force microscope that scanned the surfaces of hundreds of (sub-)micrometre sized particles in 3D with resolutions down to nanometres. This offers the unique opportunity to explore the morphology of smallest cometary dust and expand our current knowledge about cometary material.Here we give an overview of dust collected and analysed by MIDAS and highlight its most important features. These include the ubiquitous agglomerate nature of the dust, which is found at all size scales from the largest (>10 µm) through to the smallest (<1 µm) dust particles. The sub-units show characteristic sizes and shapes that are compared with model predictions for interstellar dust.Our findings constrain key parameters of the evolution of the early Solar System. We will discuss which dust growth model is favoured by the observed morphology and how the results restrict cometary formation. Finally, dust particles detected by MIDAS resemble primitive interplanetary dust which is a strong argument for a common cometary origin.

Experimental investigation of air pressure affecting filtration performance of fibrous filter sheet.

PubMed

Xu, Bin; Yu, Xiao; Wu, Ya; Lin, Zhongping

2017-03-01

Understanding the effect of air pressure on their filtration performance is important for assessing the effectiveness of fibrous filters under different practical circumstances. The effectiveness of three classes of air filter sheets were investigated in laboratory-based measurements at a wide range of air pressures (60-130 KPa). The filtration efficiency was found most sensitive to the air pressure change at smaller particle sizes. As the air pressure increased from 60 to 130 KPa, significant decrease in filtration efficiency (up to 15%) and increase in pressure drop (up to 90 Pa) were observed. The filtration efficiency of the filter sheet with largest fiber diameter and smallest solid volume fraction was affected most, while the pressure drop of the filter sheet with smallest fiber diameter and largest solid volume fraction was affected most. The effect of air pressure on the filtration efficiency was slightly larger at greater filter face air velocity. However, the effect of air pressure on the pressure drop was negligible. The filtration efficiency and pressure drop were explicitly expressed as functions of the air pressure. Two coefficients were empirically derived and successfully accounted for the effects of air pressure on filtration efficiency and pressure drop.

Kepler's Final Survey Catalog

NASA Astrophysics Data System (ADS)

Mullally, S. E.

2017-12-01

The Kepler mission was designed to detect transiting exoplanets and has succeeded in finding over 4000 candidates. These candidates include approximately 50 terrestrial-sized worlds near to the habitable zone of their GKM dwarf stars (shown in figure against the stellar temperature). However not all transit detections are created equal. False positives, such as background eclipsing binaries, can mimic the signal of a transiting planet. Additionally, at Kepler's detection limit noise, either from the star or from the detector, can create signals that also mimic a transiting planet. For the data release 25 Kepler catalog we simulated these false alarms and determined how often known false alarms are called candidates. When this reliability information is combined with our studies of catalog completeness, this catalog can be used to understand the occurrence rate of exoplanets, even for the small, temperate planet candidates found by Kepler. I will discuss the automated methods we used to create and characterize this latest catalog, highlighting how we balanced the completeness and reliability of the long period candidates. While Kepler has been very successful at detecting transiting terrestrial-sized exoplanets, many of these detections are around stars that are too dim for successful follow-up work. Future missions will pick up where Kepler left off and find small planets around some of the brightest and smallest stars.

Search for long distance correlations between extensive air showers detected by the EEE network

NASA Astrophysics Data System (ADS)

Abbrescia, M.; Baldini, L.; Baldini Ferroli, R.; Batignani, G.; Battaglieri, M.; Boi, S.; Bossini, E.; Carnesecchi, F.; Chiavassa, A.; Cicalo, C.; Cifarelli, L.; Coccetti, F.; Coccia, E.; De Gruttola, D.; De Pasquale, S.; Fabbri, F. L.; Frolov, V.; Galeotti, P.; Garbini, M.; Gemme, G.; Gnesi, I.; Grazzi, S.; Gustavino, C.; Hatzifotiadou, D.; La Rocca, P.; Mandaglio, G.; Maragoto Rodriguez, O.; Maron, G.; Mazziotta, M. N.; Miozzi, S.; Nania, R.; Noferini, F.; Nozzoli, F.; Palmonari, F.; Panareo, M.; Panetta, M. P.; Paoletti, R.; Park, W.; Perasso, L.; Pilo, F.; Piragino, G.; Pisano, S.; Riggi, F.; Righini, G. C.; Ripoli, C.; Sartorelli, G.; Scapparone, E.; Schioppa, M.; Scribano, A.; Selvi, M.; Serci, S.; Squarcia, S.; Taiuti, M.; Terreni, G.; Trifirò, A.; Trimarchi, M.; Vistoli, M. C.; Votano, L.; Williams, M. C. S.; Zheng, L.; Zichichi, A.; Zuyeuski, R.

2018-02-01

A search for long distance correlations between individual Extensive Air Showers (EAS) detected by pairs of MRPC telescopes of the Extreme Energy Events (EEE) network was carried out. The search for an anomaly in these events is the purpose of our work. A dataset obtained by all the possible 45 pairs between 10 EEE cluster sites (hosting at least two telescopes), located at relative distances between 86 and 1200km, was analyzed, corresponding to an overall period of 3968 days time exposure. To estimate the possible event excess with respect to the spurious rate, the number of coincidence events was extracted as a function of the time difference between the arrival of the showers in the two sites, from ± 10 s to the smallest time interval where events are still observed. The analysis was done taking into account both the time and orientation correlation between the showers detected by the telescope pairs. A few candidate events with unusually small time difference and angular distance were observed, with a p-value sensibly smaller than a confidence level of 0.05.

46 CFR 172.090 - Intact transverse stability.

Code of Federal Regulations, 2014 CFR

2014-10-01

... righting arm curve must be at least 5 foot-degrees (1.52 meter-degrees) up to the smallest of the following... least 10 foot-degrees (3.05 meter-degrees) up to the smallest of the following angles: (i) The angle of... service, the area under the righting arm curve must be at least 15 foot-degrees (4.57 meter-degrees) up to...

46 CFR 172.090 - Intact transverse stability.

Code of Federal Regulations, 2012 CFR

2012-10-01

... righting arm curve must be at least 5 foot-degrees (1.52 meter-degrees) up to the smallest of the following... least 10 foot-degrees (3.05 meter-degrees) up to the smallest of the following angles: (i) The angle of... service, the area under the righting arm curve must be at least 15 foot-degrees (4.57 meter-degrees) up to...

46 CFR 172.090 - Intact transverse stability.

Code of Federal Regulations, 2011 CFR

2011-10-01

... righting arm curve must be at least 5 foot-degrees (1.52 meter-degrees) up to the smallest of the following... least 10 foot-degrees (3.05 meter-degrees) up to the smallest of the following angles: (i) The angle of... service, the area under the righting arm curve must be at least 15 foot-degrees (4.57 meter-degrees) up to...

46 CFR 172.090 - Intact transverse stability.

Code of Federal Regulations, 2013 CFR

2013-10-01

... righting arm curve must be at least 5 foot-degrees (1.52 meter-degrees) up to the smallest of the following... least 10 foot-degrees (3.05 meter-degrees) up to the smallest of the following angles: (i) The angle of... service, the area under the righting arm curve must be at least 15 foot-degrees (4.57 meter-degrees) up to...

46 CFR 172.090 - Intact transverse stability.

Code of Federal Regulations, 2010 CFR

2010-10-01

... righting arm curve must be at least 5 foot-degrees (1.52 meter-degrees) up to the smallest of the following... least 10 foot-degrees (3.05 meter-degrees) up to the smallest of the following angles: (i) The angle of... service, the area under the righting arm curve must be at least 15 foot-degrees (4.57 meter-degrees) up to...

Complete mitochondrial genome of Ostrea denselamellosa (Bivalvia, Ostreidae).

PubMed

Yu, Hong; Kong, Lingfeng; Li, Qi

2016-01-01

The complete mitochondrial (mt) genome of the flat oyster, Ostrea denselamellosa, was determined using Long-PCR and genome walking techniques in this study. The total length of the mt genome sequence of O. denselamellosa was 16,227 bp, which is the smallest reported Ostreidae mt genome to date. It contained 12 protein-coding genes (lacking of ATP8), 23 transfer RNA genes, and two ribosomal RNA genes. A bias towards a higher representation of nucleotides A and T (60.7%) was detected in the mt genome of O. denselamellosa. The rrnL was split into two fragments (3' half, 711 bp; 5' half, 509 bp), which seems to be the unique characteristics of Ostreidae mt genomes.

Homozygous deletions at 3p12 in breast and lung cancer.

PubMed

Sundaresan, V; Chung, G; Heppell-Parton, A; Xiong, J; Grundy, C; Roberts, I; James, L; Cahn, A; Bench, A; Douglas, J; Minna, J; Sekido, Y; Lerman, M; Latif, F; Bergh, J; Li, H; Lowe, N; Ogilvie, D; Rabbitts, P

1998-10-01

We have constructed a physical map of the region homozygously deleted in the U2020 cell line at 3p12, including the location of putative CpG islands. Adjacent to one of these islands, we have identified and cloned a new gene (DUTT1) and used probes from this gene to detect two other homozygous deletions occurring in lung and breast carcinomas: the smallest deletion is within the gene itself and would result in a truncated protein. The DUTT1 gene is a member of the neural cell adhesion molecule family, although its widespread expression suggests it plays a less specialized role compared to other members of the family.

Environmental Qualification of a Single-Crystal Silicon Mirror for Spaceflight Use

NASA Technical Reports Server (NTRS)

Hagopian, John; Chambers, John; Rohrback. Scott; Bly, Vincent; Morell, Armando; Budinoff, Jason

2013-01-01

This innovation is the environmental qualification of a single-crystal silicon mirror for spaceflight use. The single-crystal silicon mirror technology is a previous innovation, but until now, a mirror of this type has not been qualified for spaceflight use. The qualification steps included mounting, gravity change measurements, vibration testing, vibration- induced change measurements, thermal cycling, and testing at the cold operational temperature of 225 K. Typical mirrors used for cold applications for spaceflight instruments include aluminum, beryllium, glasses, and glass-like ceramics. These materials show less than ideal behavior after cooldown. Single-crystal silicon has been demonstrated to have the smallest change due to temperature change, but has not been spaceflight-qualified for use. The advantage of using a silicon substrate is with temperature stability, since it is formed from a stress-free single crystal. This has been shown in previous testing. Mounting and environmental qualification have not been shown until this testing.

Adélie penguins coping with environmental change: Results from a natural experiment at the edge of their breeding range

USGS Publications Warehouse

Dugger, Catherine; Ballard, Grant; Ainley, David G.; Lyber, Phil O'B.; Schine, Casey

2014-01-01

We investigated life history responses to extreme variation in physical environmental conditions during a long-term demographic study of Adélie penguins at 3 colonies representing 9% of the world population and the full range of breeding colony sizes. Five years into the 14-year study (1997–2010) two very large icebergs (spanning 1.5 latitude degrees in length) grounded in waters adjacent to breeding colonies, dramatically altering environmental conditions during 2001–2005. This natural experiment allowed us to evaluate the relative impacts of expected long-term, but also extreme, short-term climate perturbations on important natural history parameters that can regulate populations. The icebergs presented physical barriers, not just to the penguins but to polynya formation, which profoundly increased foraging effort and movement rates, while reducing breeding propensity and productivity, especially at the smallest colony. We evaluated the effect of a variety of environmental parameters during breeding, molt, migration and wintering periods during years with and without icebergs on penguin breeding productivity, chick mass, and nesting chronology. The icebergs had far more influence on the natural history parameters of penguins than any of the other environmental variables measured, resulting in population level changes to metrics of reproductive performance, including delays in nesting chronology, depressed breeding productivity, and lower chick mass. These effects were strongest at the smallest, southern-most colony, which was most affected by alteration of the Ross Sea Polynya during years the iceberg was present. Additionally, chick mass was negatively correlated with colony size, supporting previous findings indicating density-dependent energetic constraints at the largest colony. Understanding the negative effects of the icebergs on the short-term natural history of Adélie penguins, as well as their response to long-term environmental variation, are important to our overall understanding of climate change effects in this and other species facing both rapid and persistent environmental change.

Ion sensing by charge transfer absorption variations of benzocrown-bipyridinium conjugates with an alkyl chain.

PubMed

Kuwabara, Tetsuo; Satake, Ryota; Guo, Haocheng

2015-01-01

Two benzocrown ether-bipyridinium conjugates, 1 and 2, each having a different length of alkyl chains with butyl and dodecyl groups, respectively, have been synthesized for the purpose of developing a new guest-responsive color-change chemosensor. Both 1 and 2 showed yellow colors with broad absorption bands around 400 nm in acetonitrile. These are associated with the intramolecular charge transfer (CT) absorption, in which the benzocrown ether and bipyridinium units act as the donor and acceptor, respectively. Upon addition of the guest; such as Na(+), they faded in color due to the blue shift in their intramolecular charge transfer absorption bands. These are associated with the formation of 1:1 host-guest inclusion complex. Analogues, 3 and 4, both being similar in structure to 1 and 2 with non-crown ether unit, also showed intramolecular CT absorptions around 400 nm, but did not change their absorption spectra upon addition of the guest because of the lack of guest-binding abilities. The guest-induced color change of 1 and 2 can be used for alkali and alkaline metal ion sensing. Both 1 and 2 could detect divalent cations such as Mg(2+) and Ca(2+) rather than univalent ones, Li(+), Na(+), K(+), Rb(+), and Cs(+). Although a marked difference between 1 and 2 was not observed in their guest sensing abilities, the remarkable recognition of 1 and 2 for Mg(2+) and Ca(2+) was found compared with that of 5, which has benzyl unit instead of alkyl chains of 1 and 2. The sensitivity values of 1 and 2 were roughly proportional to their binding constants, as shown by the binding constants with Li(+), Na(+), Mg(2+), and Ca(2+) with the values of 910, 260, 820, and 2300 M(-1) for 1 and 930, 290, 1270, and 2790 M(-1) for 2, while the binding constants of 5 were estimated to be 930, 440, 210, and 1200 M(-1) for Li(+), Na(+), Mg(2+), and Ca(2+), respectively. The limit concentration of detection of 2 for Ca(2+) was estimated to be 0.016 mM, which was the smallest value in this system.

Minimal invasive epicardial lead implantation: optimizing cardiac resynchronization with a new mapping device for epicardial lead placement.

PubMed

Maessen, J G; Phelps, B; Dekker, A L A J; Dijkman, B

2004-05-01

To optimize resynchronization in biventricular pacing with epicardial leads, mapping to determine the best pacing site, is a prerequisite. A port access surgical mapping technique was developed that allowed multiple pace site selection and reproducible lead evaluation and implantation. Pressure-volume loops analysis was used for real time guidance in targeting epicardial lead placement. Even the smallest changes in lead position revealed significantly different functional results. Optimizing the pacing site with this technique allowed functional improvement up to 40% versus random pace site selection.

Neck curve polynomials in neck rupture model

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

Kurniadi, Rizal; Perkasa, Yudha S.; Waris, Abdul

2012-06-06

The Neck Rupture Model is a model that explains the scission process which has smallest radius in liquid drop at certain position. Old fashion of rupture position is determined randomly so that has been called as Random Neck Rupture Model (RNRM). The neck curve polynomials have been employed in the Neck Rupture Model for calculation the fission yield of neutron induced fission reaction of {sup 280}X{sub 90} with changing of order of polynomials as well as temperature. The neck curve polynomials approximation shows the important effects in shaping of fission yield curve.

Reliability and Validity of the Inline Skating Skill Test.

PubMed

Radman, Ivan; Ruzic, Lana; Padovan, Viktoria; Cigrovski, Vjekoslav; Podnar, Hrvoje

2016-09-01

This study aimed to examine the reliability and validity of the inline skating skill test. Based on previous skating experience forty-two skaters (26 female and 16 male) were randomized into two groups (competitive level vs. recreational level). They performed the test four times, with a recovery time of 45 minutes between sessions. Prior to testing, the participants rated their skating skill using a scale from 1 to 10. The protocol included performance time measurement through a course, combining different skating techniques. Trivial changes in performance time between the repeated sessions were determined in both competitive females/males and recreational females/males (-1.7% [95% CI: -5.8-2.6%] - 2.2% [95% CI: 0.0-4.5%]). In all four subgroups, the skill test had a low mean within-individual variation (1.6% [95% CI: 1.2-2.4%] - 2.7% [95% CI: 2.1-4.0%]) and high mean inter-session correlation (ICC = 0.97 [95% CI: 0.92-0.99] - 0.99 [95% CI: 0.98-1.00]). The comparison of detected typical errors and smallest worthwhile changes (calculated as standard deviations × 0.2) revealed that the skill test was able to track changes in skaters' performances. Competitive-level skaters needed shorter time (24.4-26.4%, all p < 0.01) to complete the test in comparison to recreational-level skaters. Moreover, moderate correlation (ρ = 0.80-0.82; all p < 0.01) was observed between the participant's self-rating and achieved performance times. In conclusion, the proposed test is a reliable and valid method to evaluate inline skating skills in amateur competitive and recreational level skaters. Further studies are needed to evaluate the reproducibility of this skill test in different populations including elite inline skaters.

Precision of dual-energy X-ray absorptiometry of the knee and heel: methodology and implications for research to reduce bone mineral loss after spinal cord injury.

PubMed

Peppler, W T; Kim, W J; Ethans, K; Cowley, K C

2017-05-01

Methodological validation of dual-energy x-ray absorptiometry (DXA)-based measures of leg bone mineral density (BMD) based on the guidelines of the International Society for Clinical Densitometry. The primary objective of this study was to determine the precision of BMD estimates at the knee and heel using the manufacturer provided DXA acquisition algorithm. The secondary objective was to determine the smallest change in DXA-based measurement of BMD that should be surpassed (least significant change (LSC)) before suggesting that a biological change has occurred in the distal femur, proximal tibia and calcaneus. Academic Research Centre, Canada. Ten people with motor-complete SCI of at least 2 years duration and 10 people from the general population volunteered to have four DXA-based measurements taken of their femur, tibia and calcaneus. BMDs for seven regions of interest (RIs) were calculated, as were short-term precision (root-mean-square (RMS) standard deviation (g cm -2 ), RMS-coefficient of variation (RMS-CV, %)) and LSC. Overall, RMS-CV values were similar between SCI (3.63-10.20%, mean=5.3%) and able-bodied (1.85-5.73%, mean=4%) cohorts, despite lower absolute BMD values at each RIs in those with SCI (35%, heel to 54%, knee; P<0.0001). Precision was highest at the calcaneus and lowest at the femur. Except at the femur, RMS-CV values were under 6%. For DXA-based estimates of BMD at the distal femur, proximal tibia and calcaneus, these precision values suggest that LSC values >10% are needed to detect differences between treated and untreated groups in studies aimed at reducing bone mineral loss after SCI.

Changes of articular cartilage and subchondral bone after extracorporeal shockwave therapy in osteoarthritis of the knee

PubMed Central

Wang, Ching-Jen; Cheng, Jai-Hong; Chou, Wen-Yi; Hsu, Shan-Ling; Chen, Jen-Hung; Huang, Chien-Yiu

2017-01-01

We assessed the pathological changes of articular cartilage and subchondral bone on different locations of the knee after extracorporeal shockwave therapy (ESWT) in early osteoarthritis (OA). Rat knees under OA model by anterior cruciate ligament transaction (ACLT) and medial meniscectomy (MM) to induce OA changes. Among ESWT groups, ESWT were applied to medial (M) femur (F) and tibia (T) condyles was better than medial tibia condyle, medial femur condyle as well as medial and lateral (L) tibia condyles in gross osteoarthritic areas (p<0.05), osteophyte formation and subchondral sclerotic bone (p<0.05). Using sectional cartilage area, modified Mankin scoring system as well as thickness of calcified and un-calcified cartilage analysis, the results showed that articular cartilage damage was ameliorated and T+F(M) group had the most protection as compared with other locations (p<0.05). Detectable cartilage surface damage and proteoglycan loss were measured and T+F(M) group showed the smallest lesion score among other groups (p<0.05). Micro-CT revealed significantly improved in subchondral bone repair in all ESWT groups compared to OA group (p<0.05). There were no significantly differences in bone remodeling after ESWT groups except F(M) group. In the immunohistochemical analysis, T+F(M) group significant reduced TUNEL activity, promoted cartilage proliferation by observation of PCNA marker and reduced vascular invasion through observation of CD31 marker for angiogenesis compared to OA group (P<0.001). Overall the data suggested that the order of the effective site of ESWT was T+F(M) ≧ T(M) > T(M+L) > F(M) in OA rat knees. PMID:28367081

Changes of articular cartilage and subchondral bone after extracorporeal shockwave therapy in osteoarthritis of the knee.

PubMed

Wang, Ching-Jen; Cheng, Jai-Hong; Chou, Wen-Yi; Hsu, Shan-Ling; Chen, Jen-Hung; Huang, Chien-Yiu

2017-01-01

We assessed the pathological changes of articular cartilage and subchondral bone on different locations of the knee after extracorporeal shockwave therapy (ESWT) in early osteoarthritis (OA). Rat knees under OA model by anterior cruciate ligament transaction (ACLT) and medial meniscectomy (MM) to induce OA changes. Among ESWT groups, ESWT were applied to medial (M) femur (F) and tibia (T) condyles was better than medial tibia condyle, medial femur condyle as well as medial and lateral (L) tibia condyles in gross osteoarthritic areas (p<0.05), osteophyte formation and subchondral sclerotic bone (p<0.05). Using sectional cartilage area, modified Mankin scoring system as well as thickness of calcified and un-calcified cartilage analysis, the results showed that articular cartilage damage was ameliorated and T+F(M) group had the most protection as compared with other locations (p<0.05). Detectable cartilage surface damage and proteoglycan loss were measured and T+F(M) group showed the smallest lesion score among other groups (p<0.05). Micro-CT revealed significantly improved in subchondral bone repair in all ESWT groups compared to OA group (p<0.05). There were no significantly differences in bone remodeling after ESWT groups except F(M) group. In the immunohistochemical analysis, T+F(M) group significant reduced TUNEL activity, promoted cartilage proliferation by observation of PCNA marker and reduced vascular invasion through observation of CD31 marker for angiogenesis compared to OA group (P<0.001). Overall the data suggested that the order of the effective site of ESWT was T+F(M) ≧ T(M) > T(M+L) > F(M) in OA rat knees.

RENZI SCORE FOR OBSTRUCTED DEFECATION SYNDROME - VALIDATION OF THE PORTUGUESE VERSION ACCORDING TO THE COSMIN CHECKLIST.

PubMed

Caetano, Ana Celia; Dias, Sara; Santa-Cruz, André; Rolanda, Carla

2018-01-01

Recently, the Obstructed Defecation Syndrome score (ODS score) was developed and validated by Renzi to assess clinical staging and to allow evaluation and comparison of the efficacy of treatment of this disorder. Our goal is to validate the Portuguese version of Renzi ODS score, according to the Consensus based Standards for the selection of the Health Measurement Instruments (COSMIN) checklist. Following guidelines for cross-cultural validity, Renzi ODS score was translated into the Portuguese language. Then, a group of patients and healthy controls were invited to fill in the Renzi ODS score at baseline, after 2 weeks and 3 months, respectively. We assessed internal consistency, reliability and measurement error, content and construct validity, responsiveness and interpretability. A total of 113 individuals (77 patients; 36 healthy controls) completed the questionnaire. Seventy and 30 patients repeated the Renzi ODS score after 2 weeks and 3 months respectively. Factor analysis confirmed the unidimensionality of the scale. Cronbach's α coefficient of 0.77 supported item's homogeneity. Weighted quadratic kappa of 0.89 established test-retest reliability. The smallest detectable change at the individual level was 2.66 and at the group level was 0.30. Renzi ODS score and the total (-0.32) and physical (-0.43) SF-36 scores correlated negatively. Patient and control's groups significantly differed (11 points). The change score of Renzi ODS score between baseline and 3 months correlated negatively with the clinical evolution (-0.86). ROC analysis showed minimal important change of 2.00 with AUC 0.97. Neither floor nor ceiling effects were observed. This work validated the Portuguese version of Renzi ODS score. We can now use this reliable, responsive, and interpretable (at the group level) tool to evaluate Portuguese ODS patients.

Establishing the minimal clinically important difference for the Questionnaire of Olfactory Disorders.

PubMed

Mattos, Jose L; Schlosser, Rodney J; Mace, Jess C; Smith, Timothy L; Soler, Zachary M

2018-05-02

Olfactory-specific quality of life (QOL) can be measured using the Questionnaire of Olfactory Disorders Negative Statements (QOD-NS). Changes in the QOD-NS after treatment can be difficult to interpret since there is no standardized definition of clinically meaningful improvement. Patients with chronic rhinosinusitis (CRS) completed the QOD-NS. Four distribution-based methods were used to calculate the minimal clinically important difference (MCID): (1) one-half standard deviation (SD); (2) standard error of the mean (SEM); (3) Cohen's effect size (d) of the smallest unit of change; and (4) minimal detectable change (MDC). We also averaged all 4 of the scores together. Finally, the likelihood of achieving a MCID after sinus surgery using these methods, as well as average QOD-NS scores, was stratified by normal vs abnormal baseline QOD-NS scores. Outcomes were examined on 128 patients. The mean ± SD improvement in QOD-NS score after surgery was 4.3 ± 11.0 for the entire cohort and 9.6 ± 12.9 for those with abnormal baseline scores (p < 0.001). The MCID values using the different techniques were: (1) SD = 6.5; (2) SEM = 3.1; (3) d = 2.6; and (4) MDC = 8.6. The MCID score was 5.2 on average. For the total cohort analysis, the likelihood of reporting a MCID ranged from 26% to 51%, and 49% to 70% for patients reporting preoperative abnormal olfaction. Distribution-based MCID values of the QOD-NS range between 2.6 and 8.6 points, with an average of 5.2. When stratified by preoperative QOD-NS scores the majority of patients reporting abnormal preoperative QOD-NS scores achieved a MCID. © 2018 ARS-AAOA, LLC.

The effect of size and competition on tree growth rate in old-growth coniferous forests

USGS Publications Warehouse

Das, Adrian

2012-01-01

Tree growth and competition play central roles in forest dynamics. Yet models of competition often neglect important variation in species-specific responses. Furthermore, functions used to model changes in growth rate with size do not always allow for potential complexity. Using a large data set from old-growth forests in California, models were parameterized relating growth rate to tree size and competition for four common species. Several functions relating growth rate to size were tested. Competition models included parameters for tree size, competitor size, and competitor distance. Competitive strength was allowed to vary by species. The best ranked models (using Akaike’s information criterion) explained between 18% and 40% of the variance in growth rate, with each species showing a strong response to competition. Models indicated that relationships between competition and growth varied substantially among species. The results also suggested that the relationship between growth rate and tree size can be complex and that how we model it can affect not only our ability to detect that complexity but also whether we obtain misleading results. In this case, for three of four species, the best model captured an apparent and unexpected decline in potential growth rate for the smallest trees in the data set.

Non-destructive mapping of grain orientations in 3D by laboratory X-ray microscopy

PubMed Central

McDonald, S. A.; Reischig, P.; Holzner, C.; Lauridsen, E. M.; Withers, P. J.; Merkle, A. P.; Feser, M.

2015-01-01

The ability to characterise crystallographic microstructure, non-destructively and in three-dimensions, is a powerful tool for understanding many aspects related to damage and deformation mechanisms in polycrystalline materials. To this end, the technique of X-ray diffraction contrast tomography (DCT) using monochromatic synchrotron and polychromatic laboratory X-ray sources has been shown to be capable of mapping crystal grains and their orientations non-destructively in 3D. Here we describe a novel laboratory-based X-ray DCT modality (LabDCT), enabling the wider accessibility of the DCT technique for routine use and in-depth studies of, for example, temporal changes in crystallographic grain structure non-destructively over time through ‘4D’ in situ time-lapse studies. The capability of the technique is demonstrated by studying a titanium alloy (Ti-β21S) sample. In the current implementation the smallest grains that can be reliably detected are around 40 μm. The individual grain locations and orientations are reconstructed using the LabDCT method and the results are validated against independent measurements from phase contrast tomography and electron backscatter diffraction respectively. Application of the technique promises to provide important insights related to the roles of recrystallization and grain growth on materials properties as well as supporting 3D polycrystalline modelling of materials performance. PMID:26494523

Snake pictures draw more early attention than spider pictures in non-phobic women: evidence from event-related brain potentials.

PubMed

Van Strien, J W; Eijlers, R; Franken, I H A; Huijding, J

2014-02-01

Snakes were probably the first predators of mammals and may have been important agents of evolutionary changes in the primate visual system allowing rapid visual detection of fearful stimuli (Isbell, 2006). By means of early and late attention-related brain potentials, we examined the hypothesis that more early visual attention is automatically allocated to snakes than to spiders. To measure the early posterior negativity (EPN), 24 healthy, non-phobic women watched the random rapid serial presentation of 600 snake pictures, 600 spider pictures, and 600 bird pictures (three pictures per second). To measure the late positive potential (LPP), they also watched similar pictures (30 pictures per stimulus category) in a non-speeded presentation. The EPN amplitude was largest for snake pictures, intermediate for spider pictures and smallest for bird pictures. The LPP was significantly larger for both snake and spider pictures when compared to bird pictures. Interestingly, spider fear (as measured by a questionnaire) was associated with EPN amplitude for spider pictures, whereas snake fear was not associated with EPN amplitude for snake pictures. The results suggest that ancestral priorities modulate the early capture of visual attention and that early attention to snakes is more innate and independent of reported fear. Copyright © 2013 Elsevier B.V. All rights reserved.

A theoretical study on metal atom-modified BC3 sheets for effects of gas molecule adsorptions

NASA Astrophysics Data System (ADS)

Tang, Yanan; Cui, Xiao; Chen, Weiguang; Zhu, Dalei; Chai, Huaduo; Dai, Xianqi

2018-06-01

Based on the first-principle calculations, the chemical reactivity of transition metal (Fe, Co, Ni, and Cu) dopants within BC3 sheets toward toxic gas molecules (CO, NO, NO2, SO2, and HCN) is comparably investigated. First, the adsorbed gases on metal-modified BC3 sheets exhibit the different stability. Compared with other gases, the metal-modified BC3 substrates exhibit the stronger affinity toward the NO and NO2 molecules (> 1.0 eV), while the adsorbed HCN has the smallest adsorption energy, illustrating that the NO and NO2 as specific toxic gas molecule can be easily detected. Second, the adsorbed gas molecules can effectively regulate the electronic structure and magnetic property of BC3 systems. Fox example, the strong adsorption of NO and NO2 on Fe-modified BC3 systems exhibits non-magnetic property, yet these gases on Co modified BC3 systems exhibit the magnetic character. In addition, the adsorbed NO and SO2 can induce and turn the degree of magnetic moments of Ni- and Cu-modified BC3 systems. Therefore, the different kinds of adsorbed gases on metal-modified BC3 sheets can be distinguished through investigating the changed magnetic moments of system, which would provide important information for designing the functional BC3-based materials.

Ultrasound Induced Fluorescence of Nanoscale Liposome Contrast Agents

PubMed Central

Zhang, Qimei; Morgan, Stephen P.; O’Shea, Paul; Mather, Melissa L.

2016-01-01

A new imaging contrast agent is reported that provides an increased fluorescent signal upon application of ultrasound (US). Liposomes containing lipids labelled with pyrene were optically excited and the excimer fluorescence emission intensity was detected in the absence and presence of an ultrasound field using an acousto-fluorescence setup. The acousto-fluorescence dynamics of liposomes containing lipids with pyrene labelled on the fatty acid tail group (PyPC) and the head group (PyPE) were compared. An increase in excimer emission intensity following exposure to US was observed for both cases studied. The increased intensity and time constants were found to be different for the PyPC and PyPE systems, and dependent on the applied US pressure and exposure time. The greatest change in fluorescence intensity (130%) and smallest rise time constant (0.33 s) are achieved through the use of PyPC labelled liposomes. The mechanism underlying the observed increase of the excimer emission intensity in PyPC labelled liposomes is proposed to arise from the “wagging” of acyl chains which involves fast response and requires lower US pressure. This is accompanied by increased lipid lateral diffusivity at higher ultrasound pressures, a mechanism that is also active in the PyPE labelled liposomes. PMID:27467748

Fast synthesis of platinum nanopetals and nanospheres for highly-sensitive non-enzymatic detection of glucose and selective sensing of ions

NASA Astrophysics Data System (ADS)

Taurino, Irene; Sanzó, Gabriella; Mazzei, Franco; Favero, Gabriele; de Micheli, Giovanni; Carrara, Sandro

2015-10-01

Novel methods to obtain Pt nanostructured electrodes have raised particular interest due to their high performance in electrochemistry. Several nanostructuration methods proposed in the literature use costly and bulky equipment or are time-consuming due to the numerous steps they involve. Here, Pt nanostructures were produced for the first time by one-step template-free electrodeposition on Pt bare electrodes. The change in size and shape of the nanostructures is proven to be dependent on the deposition parameters and on the ratio between sulphuric acid and chloride-complexes (i.e., hexachloroplatinate or tetrachloroplatinate). To further improve the electrochemical properties of electrodes, depositions of Pt nanostructures on previously synthesised Pt nanostructures are also performed. The electroactive surface areas exhibit a two order of magnitude improvement when Pt nanostructures with the smallest size are used. All the biosensors based on Pt nanostructures and immobilised glucose oxidase display higher sensitivity as compared to bare Pt electrodes. Pt nanostructures retained an excellent electrocatalytic activity towards the direct oxidation of glucose. Finally, the nanodeposits were proven to be an excellent solid contact for ion measurements, significantly improving the time-stability of the potential. The use of these new nanostructured coatings in electrochemical sensors opens new perspectives for multipanel monitoring of human metabolism.

Disseminating the unit of mass from multiple primary realisations

NASA Astrophysics Data System (ADS)

Nielsen, Lars

2016-12-01

When a new definition of the kilogram has been adopted in 2018 as expected, the unit of mass will be realised by the watt balance method, the x-ray crystal density method or perhaps other primary methods still to be developed. So far, the standard uncertainties associated with the available primary methods are at least one order of magnitude larger than the standard uncertainty associated with mass comparisons using mass comparators, so differences in primary realisations of the kilogram are easily detected, whereas many National Metrology Institutes would have to increase their calibration and measurement capabilities (CMCs) if they were traceable to a single primary realisation. This paper presents a scheme for obtaining traceability to multiple primary realisations of the kilogram using a small group of stainless steel 1 kg weights, which are allowed to change their masses over time in a way known to be realistic, and which are calibrated and stored in air. An analysis of the scheme shows that if the relative standard uncertainties of future primary realisations are equal to the relative standard uncertainties of the present methods used to measure the Planck constant, the unit of mass can be disseminated with a standard uncertainty less than 0.015 mg, which matches the smallest CMCs currently claimed for the calibration of 1 kg weights.

Non-destructive mapping of grain orientations in 3D by laboratory X-ray microscopy

NASA Astrophysics Data System (ADS)

McDonald, S. A.; Reischig, P.; Holzner, C.; Lauridsen, E. M.; Withers, P. J.; Merkle, A. P.; Feser, M.

2015-10-01

The ability to characterise crystallographic microstructure, non-destructively and in three-dimensions, is a powerful tool for understanding many aspects related to damage and deformation mechanisms in polycrystalline materials. To this end, the technique of X-ray diffraction contrast tomography (DCT) using monochromatic synchrotron and polychromatic laboratory X-ray sources has been shown to be capable of mapping crystal grains and their orientations non-destructively in 3D. Here we describe a novel laboratory-based X-ray DCT modality (LabDCT), enabling the wider accessibility of the DCT technique for routine use and in-depth studies of, for example, temporal changes in crystallographic grain structure non-destructively over time through ‘4D’ in situ time-lapse studies. The capability of the technique is demonstrated by studying a titanium alloy (Ti-β21S) sample. In the current implementation the smallest grains that can be reliably detected are around 40 μm. The individual grain locations and orientations are reconstructed using the LabDCT method and the results are validated against independent measurements from phase contrast tomography and electron backscatter diffraction respectively. Application of the technique promises to provide important insights related to the roles of recrystallization and grain growth on materials properties as well as supporting 3D polycrystalline modelling of materials performance.

Non-destructive mapping of grain orientations in 3D by laboratory X-ray microscopy.

PubMed

McDonald, S A; Reischig, P; Holzner, C; Lauridsen, E M; Withers, P J; Merkle, A P; Feser, M

2015-10-23

The ability to characterise crystallographic microstructure, non-destructively and in three-dimensions, is a powerful tool for understanding many aspects related to damage and deformation mechanisms in polycrystalline materials. To this end, the technique of X-ray diffraction contrast tomography (DCT) using monochromatic synchrotron and polychromatic laboratory X-ray sources has been shown to be capable of mapping crystal grains and their orientations non-destructively in 3D. Here we describe a novel laboratory-based X-ray DCT modality (LabDCT), enabling the wider accessibility of the DCT technique for routine use and in-depth studies of, for example, temporal changes in crystallographic grain structure non-destructively over time through '4D' in situ time-lapse studies. The capability of the technique is demonstrated by studying a titanium alloy (Ti-β21S) sample. In the current implementation the smallest grains that can be reliably detected are around 40 μm. The individual grain locations and orientations are reconstructed using the LabDCT method and the results are validated against independent measurements from phase contrast tomography and electron backscatter diffraction respectively. Application of the technique promises to provide important insights related to the roles of recrystallization and grain growth on materials properties as well as supporting 3D polycrystalline modelling of materials performance.

The Effect of Aging on the Cutaneous Microvasculature

PubMed Central

Bentov, Itay; Reed, May J

2015-01-01

Aging is associated with a progressive loss of function in all organs. Under normal conditions the physiologic compensation for age-related deficits is sufficient, but during times of stress the limitations of this reserve become evident. Explanations for this reduction in reserve include the changes in the microcirculation that occur during the normal aging process. The microcirculation is defined as the blood flow through arterioles, capillaries and venules, which are the smallest vessels in the vasculature and are embedded within organs and tissues. Optimal strategies to maintain the microvasculature following surgery and other stressors must use multifactorial approaches. Using skin as the model organ, we will review the anatomical and functional changes in the microcirculation with aging, and some of the available clinical strategies to potentially mitigate the effect of these changes on important clinical outcomes. PMID:25917013

Drought effect on weaning weight and efficiency relative to cow size in semiarid rangeland.

PubMed

Scasta, J D; Henderson, L; Smith, T

2015-12-01

Cow size has been suggested to be an important consideration for selecting cattle to match their production environment. Over the last several decades, the trend in genetic selection for maximum growth has led to gradual increases in beef cow size. An unrelated trend during this same period in the western United States has been an increase in temperature, drought frequency, and drought severity. Due to the potential influence of the increasing cow size trend on nutritional maintenance costs and production, we assessed the effect of cow size on weaning weight and efficiency in relation to drought on a semiarid high-elevation ranch in Wyoming. This study addresses a lack of empirical studies on the interaction between cow size and drought. We measured calf weaning weights of 80 Angus × Gelbvieh cows from 2011 to 2014 and assessed how drought affected weaning weights, efficiency (considered as calf weight relative to cow weight), intake requirements, and potential herd sizes relative to cow size. We stratified cows into 5 weight classes (453, 498, 544, 589, and 634 kg) as a proxy for cow size and adjusted weaning weights to a 210-d calf sex adjusted value. Cow size was a significant factor every year, with different cow sizes having advantages or disadvantages different years relative to weaning weight. However, efficiency for the smallest cows (453 kg) was always greater than efficiency for largest cows (634 kg; < 0.001). Efficiency for the smallest cows was greater in the driest year (0.41 ± 0.02) than efficiency of the largest cows in the wettest years (0.37 ± 0.01). The change in efficiency (ΔE) between wet and dry years was 0.18 for the smallest cow size and 0.02 for the largest cow size, and ΔE decreased as cow size increased. This is an indication of the ability of smaller cows to lower maintenance requirements in response to changes in the production environment but with optimal upside potential when conditions are favorable. These results indicate large cows (589 to 634 kg) do not maximize genetic potential in this production environment when conditions are optimum or provide any advantage over small or moderate size cows (453 to 544 kg) across the drought gradient.

Assessment of upper-limb capacity, performance, and developmental disregard in children with cerebral palsy: validity and reliability of the revised Video-Observation Aarts and Aarts module: Determine Developmental Disregard (VOAA-DDD-R).

PubMed

Houwink, Annemieke; Geerdink, Yvonne A; Steenbergen, Bert; Geurts, Alexander C H; Aarts, Pauline B M

2013-01-01

To investigate the validity and reliability of the revised Video-Observation Aarts and Aarts module: Determine Developmental Disregard (VOAA-DDD-R). Upper-limb capacity and performance were assessed in children with unilateral spastic cerebral palsy (CP) by measuring overall duration of affected upper-limb use and the frequency of specific behaviours during a task in which bimanual activity was demanded ('stringing beads') and stimulated ('decorating a muffin'). Developmental disregard was defined as the difference in duration of affected upper-limb use between both tasks. Raters were two occupational and one physical therapist who received 3 hours of training. Construct validity was determined by comparing children with CP with typically developing children. Intrarater, interrater, and test-retest reliability were determined using the intraclass correlation coefficient. Standard errors of measurement and smallest detectable differences were also calculated. Twenty-five children with CP (15 females, 10 males; mean age 4 y 9 mo [SD 1 y 7 mo], range 2 y 9 mo-8 y; Manual Ability Classification System levels I-III) scored lower on capacity (p=0.052) and performance (p<0.001), and higher on developmental disregard (p<0.001) than 46 age- and sex-matched typically developing children (23 males; mean age 5 y 3 mo [SD 1 y 5 mo], range 2 y 6 mo-8 y). The intraclass correlation coefficients (0.79-1.00) indicated good reliability. Absolute agreement was high, standard errors of measurement ranged from 4.5 to 6.8%, and smallest detectable differences ranged from 12.5 to 19.0%. The VOAA-DDD-R can be reliably and validly used by occupational and physical therapists to assess upper-limb capacity, performance, and developmental disregard in children (2 y 6 mo-8 y) with CP. © The Authors. Developmental Medicine & Child Neurology © 2012 Mac Keith Press.

Adaptive Morphological Feature-Based Object Classifier for a Color Imaging System

NASA Technical Reports Server (NTRS)

McDowell, Mark; Gray, Elizabeth

2009-01-01

Utilizing a Compact Color Microscope Imaging System (CCMIS), a unique algorithm has been developed that combines human intelligence along with machine vision techniques to produce an autonomous microscope tool for biomedical, industrial, and space applications. This technique is based on an adaptive, morphological, feature-based mapping function comprising 24 mutually inclusive feature metrics that are used to determine the metrics for complex cell/objects derived from color image analysis. Some of the features include: Area (total numbers of non-background pixels inside and including the perimeter), Bounding Box (smallest rectangle that bounds and object), centerX (x-coordinate of intensity-weighted, center-of-mass of an entire object or multi-object blob), centerY (y-coordinate of intensity-weighted, center-of-mass, of an entire object or multi-object blob), Circumference (a measure of circumference that takes into account whether neighboring pixels are diagonal, which is a longer distance than horizontally or vertically joined pixels), . Elongation (measure of particle elongation given as a number between 0 and 1. If equal to 1, the particle bounding box is square. As the elongation decreases from 1, the particle becomes more elongated), . Ext_vector (extremal vector), . Major Axis (the length of a major axis of a smallest ellipse encompassing an object), . Minor Axis (the length of a minor axis of a smallest ellipse encompassing an object), . Partial (indicates if the particle extends beyond the field of view), . Perimeter Points (points that make up a particle perimeter), . Roundness [(4(pi) x area)/perimeter(squared)) the result is a measure of object roundness, or compactness, given as a value between 0 and 1. The greater the ratio, the rounder the object.], . Thin in center (determines if an object becomes thin in the center, (figure-eight-shaped), . Theta (orientation of the major axis), . Smoothness and color metrics for each component (red, green, blue) the minimum, maximum, average, and standard deviation within the particle are tracked. These metrics can be used for autonomous analysis of color images from a microscope, video camera, or digital, still image. It can also automatically identify tumor morphology of stained images and has been used to detect stained cell phenomena (see figure).

Cockroaches traverse crevices, crawl rapidly in confined spaces, and inspire a soft, legged robot

PubMed Central

Jayaram, Kaushik; Full, Robert J.

2016-01-01

Jointed exoskeletons permit rapid appendage-driven locomotion but retain the soft-bodied, shape-changing ability to explore confined environments. We challenged cockroaches with horizontal crevices smaller than a quarter of their standing body height. Cockroaches rapidly traversed crevices in 300–800 ms by compressing their body 40–60%. High-speed videography revealed crevice negotiation to be a complex, discontinuous maneuver. After traversing horizontal crevices to enter a vertically confined space, cockroaches crawled at velocities approaching 60 cm⋅s−1, despite body compression and postural changes. Running velocity, stride length, and stride period only decreased at the smallest crevice height (4 mm), whereas slipping and the probability of zigzag paths increased. To explain confined-space running performance limits, we altered ceiling and ground friction. Increased ceiling friction decreased velocity by decreasing stride length and increasing slipping. Increased ground friction resulted in velocity and stride length attaining a maximum at intermediate friction levels. These data support a model of an unexplored mode of locomotion—“body-friction legged crawling” with body drag, friction-dominated leg thrust, but no media flow as in air, water, or sand. To define the limits of body compression in confined spaces, we conducted dynamic compressive cycle tests on living animals. Exoskeletal strength allowed cockroaches to withstand forces 300 times body weight when traversing the smallest crevices and up to nearly 900 times body weight without injury. Cockroach exoskeletons provided biological inspiration for the manufacture of an origami-style, soft, legged robot that can locomote rapidly in both open and confined spaces. PMID:26858443

Cockroaches traverse crevices, crawl rapidly in confined spaces, and inspire a soft, legged robot.

PubMed

Jayaram, Kaushik; Full, Robert J

2016-02-23

Jointed exoskeletons permit rapid appendage-driven locomotion but retain the soft-bodied, shape-changing ability to explore confined environments. We challenged cockroaches with horizontal crevices smaller than a quarter of their standing body height. Cockroaches rapidly traversed crevices in 300-800 ms by compressing their body 40-60%. High-speed videography revealed crevice negotiation to be a complex, discontinuous maneuver. After traversing horizontal crevices to enter a vertically confined space, cockroaches crawled at velocities approaching 60 cm⋅s(-1), despite body compression and postural changes. Running velocity, stride length, and stride period only decreased at the smallest crevice height (4 mm), whereas slipping and the probability of zigzag paths increased. To explain confined-space running performance limits, we altered ceiling and ground friction. Increased ceiling friction decreased velocity by decreasing stride length and increasing slipping. Increased ground friction resulted in velocity and stride length attaining a maximum at intermediate friction levels. These data support a model of an unexplored mode of locomotion--"body-friction legged crawling" with body drag, friction-dominated leg thrust, but no media flow as in air, water, or sand. To define the limits of body compression in confined spaces, we conducted dynamic compressive cycle tests on living animals. Exoskeletal strength allowed cockroaches to withstand forces 300 times body weight when traversing the smallest crevices and up to nearly 900 times body weight without injury. Cockroach exoskeletons provided biological inspiration for the manufacture of an origami-style, soft, legged robot that can locomote rapidly in both open and confined spaces.

Agile science: creating useful products for behavior change in the real world.

PubMed

Hekler, Eric B; Klasnja, Predrag; Riley, William T; Buman, Matthew P; Huberty, Jennifer; Rivera, Daniel E; Martin, Cesar A

2016-06-01

Evidence-based practice is important for behavioral interventions but there is debate on how best to support real-world behavior change. The purpose of this paper is to define products and a preliminary process for efficiently and adaptively creating and curating a knowledge base for behavior change for real-world implementation. We look to evidence-based practice suggestions and draw parallels to software development. We argue to target three products: (1) the smallest, meaningful, self-contained, and repurposable behavior change modules of an intervention; (2) "computational models" that define the interaction between modules, individuals, and context; and (3) "personalization" algorithms, which are decision rules for intervention adaptation. The "agile science" process includes a generation phase whereby contender operational definitions and constructs of the three products are created and assessed for feasibility and an evaluation phase, whereby effect size estimates/casual inferences are created. The process emphasizes early-and-often sharing. If correct, agile science could enable a more robust knowledge base for behavior change.

Smallest Black Hole in Galactic Nucleus Detected

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2015-08-01

A team of astronomers have reported the detection of the smallest black hole (BH) ever observed in a galactic nucleus. The BH is hosted in the center of dwarf galaxy RGG 118, and it weighs in at 50,000 solar masses, according to observations made by Vivienne Baldassare of University of Michigan and her collaborators. Small Discoveries: Why is the discovery of a small nuclear BH important? Some open questions that this could help answer are: - Do the very smallest dwarf galaxies have BHs at their centers too? Though we believe that there's a giant BH at the center of every galaxy, we aren't sure how far down the size scale this holds true. - What is the formation mechanism for BHs at the center of galaxies? - What's the behavior of the M-sigma relation at the low-mass end? The M-sigma relation is an observed correlation between the mass of a galaxy's central BH and the velocity dispersion of the stars in the galaxy. This relation is incredibly useful for determining properties of distant BHs and their galaxies empirically, but little data is available to constrain the low-mass end of the relation. M-sigma relation, plotting systems with dynamically-measured black hole masses. RGG 118 is plotted as the pink star. The solid and dashed lines represent various determinations of scaling relations. Credit: Baldassare et al. 2015. Identifying a Black Hole: RGG 118 was identified as a candidate host for an accreting, nuclear BH from the catalog of dwarf galaxies observed in the Sloan Digital Sky Survey. Baldassare and her team followed up with high-resolution spectroscopy from the Clay telescope in Chile and Chandra x-ray observations. Using these observations, the team determined that RGG 118 plays host to a massive BH at its center based on three clues: 1) narrow emission line ratios, which is a signature of accretion onto a massive BH, 2) the presence of broad emission lines, indicating that gas is rotating around a central BH, and 3) the existence of an X-ray point source at the nucleus of the galaxy. The spread in the broad emission lines was what allowed Baldassare and collaborators to estimate the mass of the BH, placing it firmly on the extrapolation of the M-sigma relation. In addition to helping us further understand this relation, this unique BH also constrains nuclear BH formation: we know that pathways must produce seeds at least this large! The group hopes that continued analysis of Sloan candidates might allow for the discovery of more such BHs at the centers of dwarf galaxies. Citation: Vivienne F. Baldassare et al. 2015, ApJ, 809, L14 doi: 10.1088/2041-8205/809/1/L14

Egocentric Temporal Action Proposals.

PubMed

Shao Huang; Weiqiang Wang; Shengfeng He; Lau, Rynson W H

2018-02-01

We present an approach to localize generic actions in egocentric videos, called temporal action proposals (TAPs), for accelerating the action recognition step. An egocentric TAP refers to a sequence of frames that may contain a generic action performed by the wearer of a head-mounted camera, e.g., taking a knife, spreading jam, pouring milk, or cutting carrots. Inspired by object proposals, this paper aims at generating a small number of TAPs, thereby replacing the popular sliding window strategy, for localizing all action events in the input video. To this end, we first propose to temporally segment the input video into action atoms, which are the smallest units that may contain an action. We then apply a hierarchical clustering algorithm with several egocentric cues to generate TAPs. Finally, we propose two actionness networks to score the likelihood of each TAP containing an action. The top ranked candidates are returned as output TAPs. Experimental results show that the proposed TAP detection framework performs significantly better than relevant approaches for egocentric action detection.

Tetrahedral hydrocarbon nanoparticles in space: X-ray spectra

NASA Astrophysics Data System (ADS)

Bilalbegović, G.; Maksimović, A.; Valencic, L. A.

2018-06-01

It has been proposed, or confirmed, that diamond nanoparticles exist in various environments in space: close to active galactic nuclei, in the vicinity of supernovae and pulsars, in the interior of several planets in the Solar system, in carbon planets, and other exoplanets, carbon-rich stars, meteorites, in X-ray active Herbig Ae/Be stars, and in the interstellar medium. Using density functional theory methods, we calculate the carbon K-edge X-ray absorption spectrum of two large tetrahedral nanodiamonds: C26H32 and C51H52. We also study and test our methods on the astrophysical molecule CH4, the smallest C-H tetrahedral structure. A possible detection of nanodiamonds from X-ray spectra by future telescopes, such as the project Arcus, is proposed. Simulated spectra of the diffuse interstellar medium using Cyg X-2 as a source show that nanodiamonds studied in this work can be detected by Arcus, a high-resolution X-ray spectrometer mission selected by NASA for a Phase A concept study.

An ultra low power feature extraction and classification system for wearable seizure detection.

PubMed

Page, Adam; Pramod Tim Oates, Siddharth; Mohsenin, Tinoosh

2015-01-01

In this paper we explore the use of a variety of machine learning algorithms for designing a reliable and low-power, multi-channel EEG feature extractor and classifier for predicting seizures from electroencephalographic data (scalp EEG). Different machine learning classifiers including k-nearest neighbor, support vector machines, naïve Bayes, logistic regression, and neural networks are explored with the goal of maximizing detection accuracy while minimizing power, area, and latency. The input to each machine learning classifier is a 198 feature vector containing 9 features for each of the 22 EEG channels obtained over 1-second windows. All classifiers were able to obtain F1 scores over 80% and onset sensitivity of 100% when tested on 10 patients. Among five different classifiers that were explored, logistic regression (LR) proved to have minimum hardware complexity while providing average F-1 score of 91%. Both ASIC and FPGA implementations of logistic regression are presented and show the smallest area, power consumption, and the lowest latency when compared to the previous work.

Contrast-enhanced intravascular ultrasound pulse sequences for bandwidth-limited transducers.

PubMed

Maresca, David; Renaud, Guillaume; van Soest, Gijs; Li, Xiang; Zhou, Qifa; Shung, K Kirk; de Jong, Nico; van der Steen, Antonius F W

2013-04-01

We demonstrate two methods for vasa vasorum imaging using contrast-enhanced intravascular ultrasound, which can be performed using commercial catheters. Plaque neovascularization was recognized as an independent marker of coronary artery plaque vulnerability. IVUS-based methods to image the microvessels available to date require high bandwidth (-6 dB relative frequency bandwidth >70%), which are not routinely available commercially. We explored the potential of ultraharmonic imaging and chirp reversal imaging for vasa vasorum imaging. In vitro recordings were performed on a tissue-mimicking phantom using a commercial ultrasound contrast agent and a transducer with a center frequency of 34 MHz and a -6 dB relative bandwidth of 56%. Acoustic peak pressures <500 kPa were used. A tissue-mimicking phantom with channels down to 200 μm in diameter was successfully imaged by the two contrast detection sequences while the smallest channel stayed invisible in conventional intravascular ultrasound images. Ultraharmonic imaging provided the best contrast agent detection. Copyright © 2013 World Federation for Ultrasound in Medicine & Biology. All rights reserved.

Estimating the resolution limit of the map equation in community detection

NASA Astrophysics Data System (ADS)

Kawamoto, Tatsuro; Rosvall, Martin

2015-01-01

A community detection algorithm is considered to have a resolution limit if the scale of the smallest modules that can be resolved depends on the size of the analyzed subnetwork. The resolution limit is known to prevent some community detection algorithms from accurately identifying the modular structure of a network. In fact, any global objective function for measuring the quality of a two-level assignment of nodes into modules must have some sort of resolution limit or an external resolution parameter. However, it is yet unknown how the resolution limit affects the so-called map equation, which is known to be an efficient objective function for community detection. We derive an analytical estimate and conclude that the resolution limit of the map equation is set by the total number of links between modules instead of the total number of links in the full network as for modularity. This mechanism makes the resolution limit much less restrictive for the map equation than for modularity; in practice, it is orders of magnitudes smaller. Furthermore, we argue that the effect of the resolution limit often results from shoehorning multilevel modular structures into two-level descriptions. As we show, the hierarchical map equation effectively eliminates the resolution limit for networks with nested multilevel modular structures.

Structural Information Detection Based Filter for GF-3 SAR Images

NASA Astrophysics Data System (ADS)

Sun, Z.; Song, Y.

2018-04-01

GF-3 satellite with high resolution, large swath, multi-imaging mode, long service life and other characteristics, can achieve allweather and all day monitoring for global land and ocean. It has become the highest resolution satellite system in the world with the C-band multi-polarized synthetic aperture radar (SAR) satellite. However, due to the coherent imaging system, speckle appears in GF-3 SAR images, and it hinders the understanding and interpretation of images seriously. Therefore, the processing of SAR images has big challenges owing to the appearance of speckle. The high-resolution SAR images produced by the GF-3 satellite are rich in information and have obvious feature structures such as points, edges, lines and so on. The traditional filters such as Lee filter and Gamma MAP filter are not appropriate for the GF-3 SAR images since they ignore the structural information of images. In this paper, the structural information detection based filter is constructed, successively including the point target detection in the smallest window, the adaptive windowing method based on regional characteristics, and the most homogeneous sub-window selection. The despeckling experiments on GF-3 SAR images demonstrate that compared with the traditional filters, the proposed structural information detection based filter can well preserve the points, edges and lines as well as smooth the speckle more sufficiently.

When Interference Helps: Increasing Executive Load to Facilitate Deception Detection in the Concealed Information Test

PubMed Central

Visu-Petra, George; Varga, Mihai; Miclea, Mircea; Visu-Petra, Laura

2013-01-01

The possibility to enhance the detection efficiency of the Concealed Information Test (CIT) by increasing executive load was investigated, using an interference design. After learning and executing a mock crime scenario, subjects underwent three deception detection tests: an RT-based CIT, an RT-based CIT plus a concurrent memory task (CITMem), and an RT-based CIT plus a concurrent set-shifting task (CITShift). The concealed information effect, consisting in increased RT and lower response accuracy for probe items compared to irrelevant items, was evidenced across all three conditions. The group analyses indicated a larger difference between RTs to probe and irrelevant items in the dual-task conditions, but this difference was not translated in a significantly increased detection efficiency at an individual level. Signal detection parameters based on the comparison with a simulated innocent group showed accurate discrimination for all conditions. Overall response accuracy on the CITMem was highest and the difference between response accuracy to probes and irrelevants was smallest in this condition. Accuracy on the concurrent tasks (Mem and Shift) was high, and responses on these tasks were significantly influenced by CIT stimulus type (probes vs. irrelevants). The findings are interpreted in relation to the cognitive load/dual-task interference literature, generating important insights for research on the involvement of executive functions in deceptive behavior. PMID:23543918

FluBreaks: early epidemic detection from Google flu trends.

PubMed

Pervaiz, Fahad; Pervaiz, Mansoor; Abdur Rehman, Nabeel; Saif, Umar

2012-10-04

The Google Flu Trends service was launched in 2008 to track changes in the volume of online search queries related to flu-like symptoms. Over the last few years, the trend data produced by this service has shown a consistent relationship with the actual number of flu reports collected by the US Centers for Disease Control and Prevention (CDC), often identifying increases in flu cases weeks in advance of CDC records. However, contrary to popular belief, Google Flu Trends is not an early epidemic detection system. Instead, it is designed as a baseline indicator of the trend, or changes, in the number of disease cases. To evaluate whether these trends can be used as a basis for an early warning system for epidemics. We present the first detailed algorithmic analysis of how Google Flu Trends can be used as a basis for building a fully automated system for early warning of epidemics in advance of methods used by the CDC. Based on our work, we present a novel early epidemic detection system, called FluBreaks (dritte.org/flubreaks), based on Google Flu Trends data. We compared the accuracy and practicality of three types of algorithms: normal distribution algorithms, Poisson distribution algorithms, and negative binomial distribution algorithms. We explored the relative merits of these methods, and related our findings to changes in Internet penetration and population size for the regions in Google Flu Trends providing data. Across our performance metrics of percentage true-positives (RTP), percentage false-positives (RFP), percentage overlap (OT), and percentage early alarms (EA), Poisson- and negative binomial-based algorithms performed better in all except RFP. Poisson-based algorithms had average values of 99%, 28%, 71%, and 76% for RTP, RFP, OT, and EA, respectively, whereas negative binomial-based algorithms had average values of 97.8%, 17.8%, 60%, and 55% for RTP, RFP, OT, and EA, respectively. Moreover, the EA was also affected by the region's population size. Regions with larger populations (regions 4 and 6) had higher values of EA than region 10 (which had the smallest population) for negative binomial- and Poisson-based algorithms. The difference was 12.5% and 13.5% on average in negative binomial- and Poisson-based algorithms, respectively. We present the first detailed comparative analysis of popular early epidemic detection algorithms on Google Flu Trends data. We note that realizing this opportunity requires moving beyond the cumulative sum and historical limits method-based normal distribution approaches, traditionally employed by the CDC, to negative binomial- and Poisson-based algorithms to deal with potentially noisy search query data from regions with varying population and Internet penetrations. Based on our work, we have developed FluBreaks, an early warning system for flu epidemics using Google Flu Trends.

Testing life history predictions in a long-lived seabird: A population matrix approach with improved parameter estimation

USGS Publications Warehouse

Doherty, P.F.; Schreiber, E.A.; Nichols, J.D.; Hines, J.E.; Link, W.A.; Schenk, G.A.; Schreiber, R.W.

2004-01-01

Life history theory and associated empirical generalizations predict that population growth rate (λ) in long-lived animals should be most sensitive to adult survival; the rates to which λ is most sensitive should be those with the smallest temporal variances; and stochastic environmental events should most affect the rates to which λ is least sensitive. To date, most analyses attempting to examine these predictions have been inadequate, their validity being called into question by problems in estimating parameters, problems in estimating the variability of parameters, and problems in measuring population sensitivities to parameters. We use improved methodologies in these three areas and test these life-history predictions in a population of red-tailed tropicbirds (Phaethon rubricauda). We support our first prediction that λ is most sensitive to survival rates. However the support for the second prediction that these rates have the smallest temporal variance was equivocal. Previous support for the second prediction may be an artifact of a high survival estimate near the upper boundary of 1 and not a result of natural selection canalizing variances alone. We did not support our third prediction that effects of environmental stochasticity (El Niño) would most likely be detected in vital rates to which λ was least sensitive and which are thought to have high temporal variances. Comparative data-sets on other seabirds, within and among orders, and in other locations, are needed to understand these environmental effects.

The Estimation of Gestational Age at Birth in Database Studies.

PubMed

Eberg, Maria; Platt, Robert W; Filion, Kristian B

2017-11-01

Studies on the safety of prenatal medication use require valid estimation of the pregnancy duration. However, gestational age is often incompletely recorded in administrative and clinical databases. Our objective was to compare different approaches to estimating the pregnancy duration. Using data from the Clinical Practice Research Datalink and Hospital Episode Statistics, we examined the following four approaches to estimating missing gestational age: (1) generalized estimating equations for longitudinal data; (2) multiple imputation; (3) estimation based on fetal birth weight and sex; and (4) conventional approaches that assigned a fixed value (39 weeks for all or 39 weeks for full term and 35 weeks for preterm). The gestational age recorded in Hospital Episode Statistics was considered the gold standard. We conducted a simulation study comparing the described approaches in terms of estimated bias and mean square error. A total of 25,929 infants from 22,774 mothers were included in our "gold standard" cohort. The smallest average absolute bias was observed for the generalized estimating equation that included birth weight, while the largest absolute bias occurred when assigning 39-week gestation to all those with missing values. The smallest mean square errors were detected with generalized estimating equations while multiple imputation had the highest mean square errors. The use of generalized estimating equations resulted in the most accurate estimation of missing gestational age when birth weight information was available. In the absence of birth weight, assignment of fixed gestational age based on term/preterm status may be the optimal approach.

Growth of 2D heterostructures of graphene/BN

NASA Astrophysics Data System (ADS)

Hwang, Jeonghyun; Calderon, Brian R.; Alsalman, Hussain A.; Kwak, Joon Young; Kim, Moonkyung; Spencer, Michael G.

2014-06-01

Metal free direct growth of graphene on h-BN using a high temperature (~1550°C) chemical vapor deposition technique was done under Ar environment. Growth temperature, methane partial pressure, hydrogen/methane flow ratio, and growth time were varied and optimized. Raman spectroscopy clearly showed the signature of graphene with G- (~1580cm-1) and 2D-mode (~2700cm-1). The smallest width of G- and 2D-peak was 30 and 55cm-1, respectively, and the Raman I2D/IG ratio varied between 0.7 and 1.8. Raman D-peak (~1350cm-1) shows a strong dependence on growth temperature with the smallest ID/IG value of 0.15 at 1550°C. In the case of long growth, nitrogen and boron doping were detected by x-ray photoelectron spectroscopy with a small Raman D'-peak. A continuous graphene film with the rms roughness (1×1 μm2 area) of 0.32nm was shown by atomic force microscopy. Early stage of growth revealed circular shaped nucleation islands, the density and heights of which are ~15/μm2 and 1-2 graphene monolayer (ML), respectively. The hydrogen/methane flow ratio was found to be a critical parameter to obtain smooth 2D growth. Growth of h-BN is performed with ammonia borane, hydrogen and Ar. The growth is found to be critically dependent on the conditions of the ammonia boran precursor. Reproducible continuous films of h-BN are reported.

High-precision thermal expansion measurements using small Fabry-Perot etalons

NASA Astrophysics Data System (ADS)

Davis, Mark J.; Hayden, Joseph S.; Farber, Daniel L.

2007-09-01

Coefficient of thermal expansion (CTE) measurements using small Fabry-Perot etalons were conducted on high and low thermal expansion materials differing in CTE by a factor of nearly 400. The smallest detectable change in length was ~10 -12 m. The sample consisted of a mm-sized Fabry-Perot etalon equipped with spherical mirrors; the material-under-test served as the 2.5 mm-thick spacer between the mirrors. A heterodyne optical setup was used with one laser locked to an ~780 nm hyperfine line of Rb gas and the other locked to a resonance of the sample etalon; changes in the beat frequency between the two lasers as a function of temperature directly provided a CTE value. The measurement system was tested using the high-CTE SCHOTT optical glass N-KF9 (CTE = 9.5 ppm/K at 23 °C). Measurements conducted under reproducibility conditions using five identically-prepared N-KF9 etalons demonstrate a precision of 0.1 ppm/K; absolute values (accuracy) are within 2-sigma errors with those made using mechanical dilatometers with 100-mm long sample rods. Etalon-based CTE measurements were also made on a high-CTE (~10.5 ppm/K), proprietary glass-ceramic used for high peak-pressure electrical feedthroughs and revealed statistically significant differences among parts made under what were assumed to be identical conditions. Finally, CTE measurements were made on etalons constructed from SCHOTT's ultra-low CTE Zerodur (R) glass-ceramic (CTE about -20 ppb/K at 50 °C for the material tested herein).

Timing Noise in PSR 1821-24 : a Micro-Glitch Observed in a Recycled Millisecond Pulsar

NASA Astrophysics Data System (ADS)

Cognard, I.; Backer, D. C.

2005-07-01

We report the observation of a very small glitch observed for the first time in a millisecond pulsar, PSR B1821-24, located in the globular cluster M28. Timing observations were mainly conducted with the Nançay radiotelescope and confirmation comes from the 140-ft Green Bank telescope data. This event is characterized by a rotation frequency step of 3 nHz or 10-11 in fractional frequency change. Timing residuals of 1821-24 at Nançay and Green Bank (crux) obtained with a set of pulsar parameters adjusted up to Feb 2001 are shown in the left figure below. After March 2001, both TOAs from original set of parameters and TOAs obtained with a {Δ P}/P change of 10-11 are also shown. The evolution of the PSR B1821-24 rotational frequency is shown on the right. This glitch follows the main characteristics of those in the slow period pulsars, but is two orders of magnitude smaller than the smallest ever recorded. Such an event must be very rare in millisecond pulsars since no other glitches have been detected when the cumulated number of years of millisecond pulsar timing observations up to 2001 is around 500 for all these objects. We should, however, keep in mind that PSR B1821-24 is one of the youngest among the old recycled pulsars. While this event happens on a much smaller scale, the required adjustment of the star to a new equilibrium figure as it spins down is a likely common cause for all glitches.

Coalescent Modelling Suggests Recent Secondary-Contact of Cryptic Penguin Species

PubMed Central

Grosser, Stefanie; Burridge, Christopher P.; Peucker, Amanda J.; Waters, Jonathan M.

2015-01-01

Molecular genetic analyses present powerful tools for elucidating demographic and biogeographic histories of taxa. Here we present genetic evidence showing a dynamic history for two cryptic lineages within Eudyptula, the world's smallest penguin. Specifically, we use a suite of genetic markers to reveal that two congeneric taxa ('Australia' and 'New Zealand') co-occur in southern New Zealand, with only low levels of hybridization. Coalescent modelling suggests that the Australian little penguin only recently expanded into southern New Zealand. Analyses conducted under time-dependent molecular evolutionary rates lend support to the hypothesis of recent anthropogenic turnover, consistent with shifts detected in several other New Zealand coastal vertebrate taxa. This apparent turnover event highlights the dynamic nature of the region’s coastal ecosystem. PMID:26675310

Coalescent Modelling Suggests Recent Secondary-Contact of Cryptic Penguin Species.

PubMed

Grosser, Stefanie; Burridge, Christopher P; Peucker, Amanda J; Waters, Jonathan M

2015-01-01

Molecular genetic analyses present powerful tools for elucidating demographic and biogeographic histories of taxa. Here we present genetic evidence showing a dynamic history for two cryptic lineages within Eudyptula, the world's smallest penguin. Specifically, we use a suite of genetic markers to reveal that two congeneric taxa ('Australia' and 'New Zealand') co-occur in southern New Zealand, with only low levels of hybridization. Coalescent modelling suggests that the Australian little penguin only recently expanded into southern New Zealand. Analyses conducted under time-dependent molecular evolutionary rates lend support to the hypothesis of recent anthropogenic turnover, consistent with shifts detected in several other New Zealand coastal vertebrate taxa. This apparent turnover event highlights the dynamic nature of the region's coastal ecosystem.

General Relativity Today

NASA Astrophysics Data System (ADS)

Blandford, Roger D.

2016-01-01

A hundred years after its birth, general relativity has become a highly successful theory in the sese that it has passed many experimental and observational tests and finds widespread application to diverse set of cosmic phenomena. It remains an accurate research field as more tests are deployed, epitomized by the exciting prospect of detecting gravitational radiation directly. General realtivity is the essential foundation of modern cosmology and underlies our detailed description of the black holes and neutron stars that are ultimately responsible for the most powerful and dramatic cosmic sources. The interface with physics on both the largest and the smallest scales continues to be very fertile. In this talk I will attempt to highlight some key steps along the way to general relativity today.

A century of general relativity: Astrophysics and cosmology

NASA Astrophysics Data System (ADS)

Blandford, R. D.

2015-03-01

One hundred years after its birth, general relativity has become a highly successful physical theory in the sense that it has passed a large number of experimental and observational tests and finds extensive application to a wide variety of cosmic phenomena. It remains an active area of research as new tests are on the way, epitomized by the exciting prospect of detecting gravitational waves from merging black holes. General relativity is the essential foundation of the standard model of cosmology and underlies our description of the black holes and neutron stars that are ultimately responsible for the most powerful and dramatic cosmic sources. Its interface with physics on the smallest and largest scales will continue to provide fertile areas of investigation in its next century.

Simultaneous observation of chemomechanical coupling of a molecular motor.

PubMed

Nishizaka, Takayuki; Hasimoto, Yuh; Masaike, Tomoko

2011-01-01

F(1)-ATPase is the smallest rotary molecular motor ever found. Unidirectional rotation of the γ-shaft is driven by precisely coordinated sequential ATP hydrolysis reactions in three catalytic sites arranged 120° apart in the cylinder. Single-molecule observation allows us to directly watch the rotation of the shaft using micron-sized plastic beads. Additionally, an advanced version of "total internal reflection fluorescence microscope (TIRFM)" enables us to detect binding and release of energy currency through fluorescently labeled ATP. In this chapter, we describe how to set up the system for simultaneous observation of these two critical events. This specialized optical setup is applicable to a variety of research, not only molecular motors but also other single-molecule topics.

ELIPGRID-PC: A PC program for calculating hot spot probabilities

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

Davidson, J.R.

1994-10-01

ELIPGRID-PC, a new personal computer program has been developed to provide easy access to Singer`s 1972 ELIPGRID algorithm for hot-spot detection probabilities. Three features of the program are the ability to determine: (1) the grid size required for specified conditions, (2) the smallest hot spot that can be sampled with a given probability, and (3) the approximate grid size resulting from specified conditions and sampling cost. ELIPGRID-PC also provides probability of hit versus cost data for graphing with spread-sheets or graphics software. The program has been successfully tested using Singer`s published ELIPGRID results. An apparent error in the original ELIPGRIDmore » code has been uncovered and an appropriate modification incorporated into the new program.« less

Using passive integrated transponder (PIT) systems for terrestrial detection of blue-spotted salamanders (Ambystoma laterale) in situ

USGS Publications Warehouse

Ryan, Kevin J.; Zydlewski, Joseph D.; Calhoun, Aram J.K.

2014-01-01

Pure-diploid Blue-spotted Salamanders (Ambystoma laterale) are the smallest members of the family Ambystomatidae which makes tracking with radio-transmitters difficult because of small battery capacity. Passive integrated transponder (PIT) tags provide another tracking approach for small fossorial animals such as salamanders. We evaluated the use of portable PIT tag readers (PIT packs) to detect PIT tag-implanted pure-diploid Blue-spotted Salamanders in situ. We also examined the detection probability of salamanders with PIT tags held in enclosures in wetland and terrestrial habitats, as well as the underground detection range of PIT packs by scanning for buried tags not implanted into salamanders. Of the 532 PIT tagged salamanders, we detected 6.84% at least once during scanning surveys. We scanned systematically within a 13.37 ha area surrounding a salamander breeding pool on 34 occasions (~119 hours of survey time) and detected PIT tags 74 times. We detected 55% of PITs in tagged salamanders and 45%were expelled tags. We were able to reliably detect buried PIT tags from 1–22cm below the ground surface. Because nearly half the locations represented expelled tags, our data suggest this technique is inappropriate for future studies of pure-diploid Blue-spotted Salamanders, although it may be suitable for polyploid Blue-spotted Salamanders and other ambystomatid species, which are larger in size and may exhibit higher tag retention rates. It may also be prudent to conduct long-term tag retention studies in captivity before tagging and releasing salamanders for in situ study, and to double-mark individuals.

The mitochondrial genome of the ethanol-metabolizing, wine cellar mold Zasmidium cellare is the smallest for a filamentous ascomycete.

PubMed

Goodwin, Stephen B; McCorison, Cassandra B; Cavaletto, Jessica R; Culley, David E; LaButti, Kurt; Baker, Scott E; Grigoriev, Igor V

2016-08-01

Fungi in the class Dothideomycetes often live in extreme environments or have unusual physiology. One of these, the wine cellar mold Zasmidium cellare, produces thick curtains of mycelia in cellars with high humidity, and its ability to metabolize volatile organic compounds is thought to improve air quality. Whether these abilities have affected its mitochondrial genome is not known. To fill this gap, the circular-mapping mitochondrial genome of Z. cellare was sequenced and, at only 23 743 bp, is the smallest reported for a filamentous fungus. Genes were encoded on both strands with a single change of direction, different from most other fungi but consistent with the Dothideomycetes. Other than its small size, the only unusual feature of the Z. cellare mitochondrial genome was two copies of a 110-bp sequence that were duplicated, inverted and separated by approximately 1 kb. This inverted-repeat sequence confused the assembly program but appears to have no functional significance. The small size of the Z. cellare mitochondrial genome was due to slightly smaller genes, lack of introns and non-essential genes, reduced intergenic spacers and very few ORFs relative to other fungi rather than a loss of essential genes. Whether this reduction facilitates its unusual biology remains unknown. Published by Elsevier Ltd.

The impact of arbitrarily applicable relational responding on evaluative learning about hypothetical money and shock outcomes.

PubMed

Dymond, Simon; Molet, Mikael; Davies, Lynette

2017-08-01

Evaluative learning comprises changes in preferences after co-occurrences between conditioned stimuli (CSs) and an unconditioned stimulus (US) of affective value. Co-occurrences may involve relational responding. Two experiments examined the impact of arbitrary relational responding on evaluative preferences for hypothetical money and shock outcomes. In Experiment 1, participants were trained to make arbitrary relational responses by placing CSs of the same size but different colours into boxes and were then instructed that these CSs represented different intensities of hypothetical USs (money or shock). Liking ratings of the CSs were altered in accordance with the underlying bigger/smaller than relations. A reversal of preference was also observed: the CS associated with the smallest hypothetical shock was rated more positively than the CS associated with the smallest amount of hypothetical money. In Experiment 2, procedures from Relational Frame Theory (RFT) established a relational network of more than/less than relations consisting of five CSs (A-B-C-D-E). Overall, evaluative preferences were altered, but not reversed, depending on (a) how stimuli had been related to one another during the learning phase and (b) whether those stimuli referred to money or shocks. The contribution of RFT to evaluative learning research is discussed.

Using a smaller plate did not reduce energy intake at meals

PubMed Central

Rolls, Barbara J.; Roe, Liane S.; Halverson, Kitti H.; Meengs, Jennifer S.

2007-01-01

In three cross-over experiments, we examined the effect on energy intake of changing the size of the plate used at a meal. On separate days, adults were served the same lunch menu but were given a different-sized plate. In the first study, 45 participants used each of three plate sizes (17, 22, or 26 cm) and served the main course from a large dish. In the second study, 30 participants received an equal amount of food presented on each of the two larger plates. In the third study, 44 participants used each of the three plates and selected from a buffet of five foods matched for energy density. Results showed that plate size had no significant effect on energy intake. The mean differences in intake using the smallest and largest plates in the three studies were 21±13 g, 11±13 g, and 4±18 g, respectively, equivalent to < 142 kJ (34 kcal) and not significantly different from zero. Participants in the third study made significantly more trips to the buffet when they were given the smallest plate. These findings show that using a smaller plate did not lead to a reduction in food intake at meals eaten in the laboratory. PMID:17540474

Note: A portable pulsed neutron source based on the smallest sealed-type plasma focus device.

PubMed

Niranjan, Ram; Rout, R K; Mishra, Prabhat; Srivastava, Rohit; Rawool, A M; Kaushik, T C; Gupta, Satish C

2011-02-01

Development and operation of a portable and compact pulsed neutron source based on sealed-type plasma focus (PF) device are reported. The unit is the smallest sealed-type neutron producing PF device. The effective volume of the PF unit is 33 cm(3) only. A compact size single capacitor (4 μF) is used as the energy driver. A battery based power supply unit is used for charging the capacitor and triggering the spark gap. The PF unit is operated at 10 kV (200 J) and at a deuterium gas filling pressure of 8 mb. The device is operated over a time span of 200 days and the neutron emissions have been observed for 200 shots without changing the gas in between the shots. The maximum yield of this device is 7.8 × 10(4) neutrons/pulse. Beyond 200 shots the yield is below the threshold (1050 neutrons/pulse) of our (3)He detector. The neutron energy is evaluated using time of flight technique and the value is (2.49 ± 0.27) MeV. The measured neutron pulse width is (24 ± 5) ns. Multishot and long duration operations envisage the potentiality of such portable device for repetitive mode of operation.

Modeling Large Scale Circuits Using Massively Parallel Descrete-Event Simulation

DTIC Science & Technology

2013-06-01

exascale levels of performance, the smallest elements of a single processor can greatly affect the entire computer system (e.g. its power consumption...grow to exascale levels of performance, the smallest elements of a single processor can greatly affect the entire computer system (e.g. its power...Warp Speed 10.0. 2.0 INTRODUCTION As supercomputer systems approach exascale , the core count will exceed 1024 and number of transistors used in

Abrasive Wear of Four Direct Restorative Materials by Standard and Whitening Dentifrices

DTIC Science & Technology

2013-06-01

after an acidic challenge . Enamel loss was significantly greater when erosive and abrasive effects were combined. They concluded that acid-softened...surrounding soft tissues. Another benefit of restoration is the elimination of a challenging area for the patient and hygienist to clean. These areas...abrasion challenge ; the resin cement with the smallest sized filler particles had the smallest weight loss and maintained the smoothest surface of all the

Smallest fullerene-like silicon cage stabilized by a V(2) unit.

PubMed

Xu, Hong-Guang; Kong, Xiang-Yu; Deng, Xiao-Jiao; Zhang, Zeng-Guang; Zheng, Wei-Jun

2014-01-14

We conducted a combined anion photoelectron spectroscopy and density functional theory study on V2Si20 cluster. Our results show that the V2Si20 cluster has an elongated dodecahedron cage structure with a V2 unit encapsulated inside the cage. It is the smallest fullerene-like silicon cage and can be used as building block to make cluster-assembled materials, such as pearl-chain style nanowires.

Smallest fullerene-like silicon cage stabilized by a V2 unit

NASA Astrophysics Data System (ADS)

Xu, Hong-Guang; Kong, Xiang-Yu; Deng, Xiao-Jiao; Zhang, Zeng-Guang; Zheng, Wei-Jun

2014-01-01

We conducted a combined anion photoelectron spectroscopy and density functional theory study on V2Si20 cluster. Our results show that the V2Si20 cluster has an elongated dodecahedron cage structure with a V2 unit encapsulated inside the cage. It is the smallest fullerene-like silicon cage and can be used as building block to make cluster-assembled materials, such as pearl-chain style nanowires.

The Path Resistance Method for Bounding the Smallest Nontrivial Eigenvalue of a Laplacian

NASA Technical Reports Server (NTRS)

Guattery, Stephen; Leighton, Tom; Miller, Gary L.

1997-01-01

We introduce the path resistance method for lower bounds on the smallest nontrivial eigenvalue of the Laplacian matrix of a graph. The method is based on viewing the graph in terms of electrical circuits; it uses clique embeddings to produce lower bounds on lambda(sub 2) and star embeddings to produce lower bounds on the smallest Rayleigh quotient when there is a zero Dirichlet boundary condition. The method assigns priorities to the paths in the embedding; we show that, for an unweighted tree T, using uniform priorities for a clique embedding produces a lower bound on lambda(sub 2) that is off by at most an 0(log diameter(T)) factor. We show that the best bounds this method can produce for clique embeddings are the same as for a related method that uses clique embeddings and edge lengths to produce bounds.

An approach for maximizing the smallest eigenfrequency of structure vibration based on piecewise constant level set method

NASA Astrophysics Data System (ADS)

Zhang, Zhengfang; Chen, Weifeng

2018-05-01

Maximization of the smallest eigenfrequency of the linearized elasticity system with area constraint is investigated. The elasticity system is extended into a large background domain, but the void is vacuum and not filled with ersatz material. The piecewise constant level set (PCLS) method is applied to present two regions, the original material region and the void region. A quadratic PCLS function is proposed to represent the characteristic function. Consequently, the functional derivative of the smallest eigenfrequency with respect to PCLS function takes nonzero value in the original material region and zero in the void region. A penalty gradient algorithm is proposed, which initializes the whole background domain with the original material and decreases the area of original material region till the area constraint is satisfied. 2D and 3D numerical examples are presented, illustrating the validity of the proposed algorithm.

Effect of gravitational and inertial forces on vertical distribution of pulmonary blood flow

NASA Technical Reports Server (NTRS)

Chevalier, P. A.; Reed, J. H., Jr.; Vandenberg, R. A.; Wood, E. H.

1978-01-01

Vertical distribution of pulmonary blood flow (VDPBF) was studied, using radioactive microsphere emboli, in dogs without thoracotomy in the right decubitus position during exposure to lateral accelerations of 1, 2, 4, and 6 G. At all levels of force environment studied, an inverse linear relationship was observed between vertical height in the thorax and pulmonary blood flow (ml/min/ml lung tissue) with a decrease in flow to the most dependent region of the lung despite large increases in intravascular pressures at this site. Changes in blood flow were smallest at the mid-lung level, the hydrostatic 'balance point' for vascular and pleural pressures. These force environment-dependent changes in VDPBF are not readily explainable by the Starling resistor analog. Gravity-dependent regional differences in pleural and associated interstitial pressures, plus possible changes in vascular tone resulting from inadequate aeration of blood in the most dependent regions of the lung, probably also affect VDPBF.

Arctic Ocean

NASA Technical Reports Server (NTRS)

Parkinson, Claire L.; Zukor, Dorothy J. (Technical Monitor)

2000-01-01

The Arctic Ocean is the smallest of the Earth's four major oceans, covering 14x10(exp 6) sq km located entirely within the Arctic Circle (66 deg 33 min N). It is a major player in the climate of the north polar region and has a variable sea ice cover that tends to increase its sensitivity to climate change. Its temperature, salinity, and ice cover have all undergone changes in the past several decades, although it is uncertain whether these predominantly reflect long-term trends, oscillations within the system, or natural variability. Major changes include a warming and expansion of the Atlantic layer, at depths of 200-900 m, a warming of the upper ocean in the Beaufort Sea, a considerable thinning (perhaps as high as 40%) of the sea ice cover, a lesser and uneven retreat of the ice cover (averaging approximately 3% per decade), and a mixed pattern of salinity increases and decreases.

Influence of delayed gadolinium enhanced MRI of cartilage (dGEMRIC) protocol on T2-mapping: is it possible to comprehensively assess knee cartilage composition in one post-contrast MR examination at 3 Tesla?

PubMed

Verschueren, J; van Tiel, J; Reijman, M; Bron, E E; Klein, S; Verhaar, J A N; Bierma-Zeinstra, S M A; Krestin, G P; Wielopolski, P A; Oei, E H G

2017-09-01

To evaluate the possibility of assessing knee cartilage with T2-mapping and delayed gadolinium enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) in one post-contrast MR examination at 3 Tesla (T). T2 mapping was performed in 10 healthy volunteers at baseline; directly after baseline; after 10 min of cycling; and after 90 min delay, and in 16 osteoarthritis patients before and after intravenous administration of a double dose gadolinium dimeglumine contrast agent, reflecting key dGEMRIC protocol elements. Differences in T2 relaxation times between each timepoint and baseline were calculated for 6 cartilage regions using paired t tests or Wilcoxon signed-rank tests and the smallest detectable change (SDC). After cycling, a significant change in T2 relaxation times was found in the lateral weight-bearing tibial plateau (+1.0 ms, P = 0.04). After 90 min delay, significant changes were found in the lateral weight-bearing femoral condyle (+1.2 ms, P = 0.03) and the lateral weight-bearing tibial plateau (+1.3 ms, P = 0.01). In these regions of interests (ROIs), absolute differences were small and lower than the corresponding SDCs. T2-mapping after contrast administration only showed statistically significantly lower T2 relaxation times in the medial posterior femoral condyle (-2.4 ms, P < 0.001) with a change exceeding the SDC. Because dGEMRIC protocol elements resulted in only small differences in T2 relaxation times that were not consistent and lower than the SDC in the majority of regions, our results suggest that T2-mapping and dGEMRIC can be performed reliably in a single imaging session to assess cartilage biochemical composition in knee osteoarthritis (OA) at 3 T. Copyright © 2017 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

Contact lens materials, mucin fragmentation and relation to symptoms.

PubMed

Berry, Monica; Purslow, Chris; Murphy, Paul J; Pult, Heiko

2012-07-01

Mucins adhere to contact lenses (CLs), reflecting the renewal of the preocular fluid and enzymatic activity at the ocular surface. In this study, we aimed to analyze mucin fragmentation on materials new to the ocular surface and investigate whether this correlates with wearing comfort. Lenses were obtained from new CL wearers after 2 weeks each of wearing vifilcon A, followed by senofilcon A, and then by vifilcon A lenses. Symptoms were evaluated using the Ocular Surface Disease Index (OSDI). CLs were extracted in a mixture of guanidinium hydrochloride and radioimmunoprecipitation assay buffer. Mucin mobility was analyzed after electrophoresis, Western blotting, and visualization with antibodies against mucin peptide core. Mobilities, normalized to total reactivity in the lane, were compared between visits for each subject and were expressed as shifts. Mucin (MUC)5AC polymers exceeding 260 kDa were observed in agarose gels; NuPAGE resolved polymers from 260 to 3.5 kDa: when large mucins were detected, the smallest fragments were missing. Fragmentation patterns were significantly different between lens types for MUC1 (analysis of variance, P = 0.006) and MUC4 (P < 0.001) but not for MUC5AC or MUC16 (P > 0.293). Mobility shifts of MUC1 and MUC4 were significantly negatively correlated (Pearson, r = -0.908; P = 0.002). For OSDI scores >15, mucin fragmentation was unchanged, whereas for OSDI scores <15, MUC4 and MUC5AC fragments were longer on vifilcon A than on senofilcon lenses (unpaired t test, P = 0.046), irrespective of the direction of change (analysis of variance, P > 0.366). Changes in MUC1 breakdown were significantly negatively correlated to the overall OSDI score (r = -0.891, P = 0.001). In asymptomatic CL wearers, only changes in mucin fragmentation in response to a new material were consistent and fast, irrespective of CL order. Lack of change seems, therefore, to be connected with discomfort during CL wear.

Detection of the Secondary Eclipse of Exoplanet HAT P-11b

NASA Technical Reports Server (NTRS)

Barry, R. K.; Deming, L. D.; Bakos, G.; Harrington, J.; Madhusudhan, N.; Noyes, R.; Seager, S.

2010-01-01

We have successfully conducted secondary eclipse observations of exoplanet HAT-P-11b using the Spitzer Space Telescope. HAT-P-11b was, until very recently, the smallest transiting extrasolar planet yet found and one of only two known exo-Neptunes. We observed the system at 3.6 microns for a period of 22 hours centered on the anticipated secondary eclipse time, to detect the eclipse and determine its phase. Having detected the secondary eclipse, we are at present making a more focused series of observations in both the 3.6 and 4.5 micron bands to fully characterize it. HAT-P-11b has a period of 4.8878 days, radius of 0.422 RJ, mass of 0.081 MJ and semi-major axis 0.053 AU. Measurements of the secondary eclipse will serve to clarify two key issues; 1) the planetary brightness temperature and the nature of its atmosphere, and 2) the eccentricity of its orbit, with implications for its dynamical evolution. A precise determination of the orbit phase for the secondary eclipse will also be of great utility for Kepler observations of this system at visible wavelengths.

RAYLEIGH SCATTERING IN THE ATMOSPHERE OF THE WARM EXO-NEPTUNE GJ 3470B

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

Dragomir, Diana; Benneke, Björn; Pearson, Kyle A.

2015-12-01

GJ 3470b is a warm Neptune-size planet transiting an M dwarf star. Like the handful of other small exoplanets for which transmission spectroscopy has been obtained, GJ 3470b exhibits a flat spectrum in the near- and mid-infrared. Recently, a tentative detection of Rayleigh scattering in its atmosphere has been reported. This signal manifests itself as an observed increase of the planetary radius as a function of decreasing wavelength in the visible. We set out to verify this detection and observed several transits of this planet with the LCOGT network and the Kuiper telescope in four different bands (Sloan g, Sloanmore » i, Harris B, and Harris V). Our analysis reveals a strong Rayleigh scattering slope, thus confirming previous results. This makes GJ 3470b the smallest known exoplanet with a detection of Rayleigh scattering. We find that the most plausible scenario is a hydrogen/helium-dominated atmosphere covered by clouds which obscure absorption features in the infrared and hazes which give rise to scattering in the visible. Our results demonstrate the feasibility of exoplanet atmospheric characterization from the ground, even with meter-class telescopes.« less

Detection of periimplant fenestration and dehiscence with the use of two scan modes and the smallest voxel sizes of a cone-beam computed tomography device.

PubMed

de-Azevedo-Vaz, Sergio Lins; Vasconcelos, Karla de Faria; Neves, Frederico Sampaio; Melo, Saulo Leonardo Sousa; Campos, Paulo Sérgio Flores; Haiter-Neto, Francisco

2013-01-01

To assess the accuracy of cone-beam computed tomography (CBCT) in periimplant fenestration and dehiscence detection, and to determine the effects of 2 voxel sizes and scan modes. One hundred titanium implants were placed in bovine ribs in which periimplant fenestration and dehiscence were simulated. CBCT images were acquired with the use of 3 protocols of the i-CAT NG unit: A) 0.2 mm voxel size half-scan (180°); B) 0.2 mm voxel size full-scan (360°); and C) 0.12 mm voxel size full scan (360°). Receiver operating characteristic curves and diagnostic values were obtained. The Az values were compared with the use of analysis of variance. The Az value for dehiscence in protocol A was significantly lower than those of B or C (P < .01). They did not statistically differ for fenestration (P > .05). Protocol B yielded the highest values. The voxel sizes did not affect fenestration and dehiscence detection, and for dehiscence full-scan performed better than half-scan. Copyright © 2013 Elsevier Inc. All rights reserved.

Segmentation of human face using gradient-based approach

NASA Astrophysics Data System (ADS)

Baskan, Selin; Bulut, M. Mete; Atalay, Volkan

2001-04-01

This paper describes a method for automatic segmentation of facial features such as eyebrows, eyes, nose, mouth and ears in color images. This work is an initial step for wide range of applications based on feature-based approaches, such as face recognition, lip-reading, gender estimation, facial expression analysis, etc. Human face can be characterized by its skin color and nearly elliptical shape. For this purpose, face detection is performed using color and shape information. Uniform illumination is assumed. No restrictions on glasses, make-up, beard, etc. are imposed. Facial features are extracted using the vertically and horizontally oriented gradient projections. The gradient of a minimum with respect to its neighbor maxima gives the boundaries of a facial feature. Each facial feature has a different horizontal characteristic. These characteristics are derived by extensive experimentation with many face images. Using fuzzy set theory, the similarity between the candidate and the feature characteristic under consideration is calculated. Gradient-based method is accompanied by the anthropometrical information, for robustness. Ear detection is performed using contour-based shape descriptors. This method detects the facial features and circumscribes each facial feature with the smallest rectangle possible. AR database is used for testing. The developed method is also suitable for real-time systems.

Did LIGO Detect Dark Matter?

PubMed

Bird, Simeon; Cholis, Ilias; Muñoz, Julian B; Ali-Haïmoud, Yacine; Kamionkowski, Marc; Kovetz, Ely D; Raccanelli, Alvise; Riess, Adam G

2016-05-20

We consider the possibility that the black-hole (BH) binary detected by LIGO may be a signature of dark matter. Interestingly enough, there remains a window for masses 20M_{⊙}≲M_{bh}≲100M_{⊙} where primordial black holes (PBHs) may constitute the dark matter. If two BHs in a galactic halo pass sufficiently close, they radiate enough energy in gravitational waves to become gravitationally bound. The bound BHs will rapidly spiral inward due to the emission of gravitational radiation and ultimately will merge. Uncertainties in the rate for such events arise from our imprecise knowledge of the phase-space structure of galactic halos on the smallest scales. Still, reasonable estimates span a range that overlaps the 2-53  Gpc^{-3} yr^{-1} rate estimated from GW150914, thus raising the possibility that LIGO has detected PBH dark matter. PBH mergers are likely to be distributed spatially more like dark matter than luminous matter and have neither optical nor neutrino counterparts. They may be distinguished from mergers of BHs from more traditional astrophysical sources through the observed mass spectrum, their high ellipticities, or their stochastic gravitational wave background. Next-generation experiments will be invaluable in performing these tests.

Using Aerial Photography to Estimate Riparian Zone Impacts in a Rapidly Developing River Corridor

NASA Astrophysics Data System (ADS)

Owers, Katharine A.; Albanese, Brett; Litts, Thomas

2012-03-01

Riparian zones are critical for protecting water quality and wildlife, but are often impacted by human activities. Ongoing threats and uncertainty about the effectiveness of buffer regulations emphasize the importance of monitoring riparian buffers through time. We developed a method to rapidly categorize buffer width and landuse attributes using 2007 leaf-on aerial photography and applied it to a 65 km section of the Toccoa River in north Georgia. We repeated our protocol using 1999 leaf-off aerial photographs to assess the utility of our approach for monitoring. Almost half (45%) of the length of the Toccoa River was bordered by buffers less than 50 ft wide in 2007, with agricultural and built-up lands having the smallest buffers. The percentage of river length in each buffer width category changed little between 1999 and 2007, but we did detect a 5% decrease in agricultural land use, a corresponding increase in built-up land use, and an additional 149 buildings within 100 ft of the river. Field verification indicated that our method overestimated buffer widths and forested land use and underestimated built-up land use and the number of buildings within 100 ft of the river. Our methodology can be used to rapidly assess the status of riparian buffers. Including supplemental data (e.g., leaf-off imagery, road layers) will allow detection of the fine-scale impacts underestimated in our study. Our results on the Toccoa River reflect historic impacts, exemptions and variances to regulations, and the ongoing threat of vacation home development. We recommend additional monitoring, improvements in policy, and efforts to increase voluntary protection and restoration of stream buffers.

Using aerial photography to estimate riparian zone impacts in a rapidly developing river corridor.

PubMed

Owers, Katharine A; Albanese, Brett; Litts, Thomas

2012-03-01

Riparian zones are critical for protecting water quality and wildlife, but are often impacted by human activities. Ongoing threats and uncertainty about the effectiveness of buffer regulations emphasize the importance of monitoring riparian buffers through time. We developed a method to rapidly categorize buffer width and landuse attributes using 2007 leaf-on aerial photography and applied it to a 65 km section of the Toccoa River in north Georgia. We repeated our protocol using 1999 leaf-off aerial photographs to assess the utility of our approach for monitoring. Almost half (45%) of the length of the Toccoa River was bordered by buffers less than 50 ft wide in 2007, with agricultural and built-up lands having the smallest buffers. The percentage of river length in each buffer width category changed little between 1999 and 2007, but we did detect a 5% decrease in agricultural land use, a corresponding increase in built-up land use, and an additional 149 buildings within 100 ft of the river. Field verification indicated that our method overestimated buffer widths and forested land use and underestimated built-up land use and the number of buildings within 100 ft of the river. Our methodology can be used to rapidly assess the status of riparian buffers. Including supplemental data (e.g., leaf-off imagery, road layers) will allow detection of the fine-scale impacts underestimated in our study. Our results on the Toccoa River reflect historic impacts, exemptions and variances to regulations, and the ongoing threat of vacation home development. We recommend additional monitoring, improvements in policy, and efforts to increase voluntary protection and restoration of stream buffers.

Responsive Hydrogel-based Photonic Nanochains for Microenvironment Sensing and Imaging in Real Time and High Resolution.

PubMed

Luo, Wei; Cui, Qian; Fang, Kai; Chen, Ke; Ma, Huiru; Guan, Jianguo

2018-01-17

Microenvironment sensing and imaging are of importance in microscale zones like microreactors, microfluidic systems, and biological cells. But they are so far implemented only based on chemical colors from dyes or quantum dots, which suffered either from photobleaching, quenching, or photoblinking behaviors, or from limited color gamut. In contrast, structural colors from hydrogel-based photonic crystals (PCs) may be stable and tunable in the whole visible spectrum by diffraction peak shift, facilitating the visual detection with high accuracy. However, the current hydrogel-based PCs are all inappropriate for microscale detection due to the bulk size. Here we demonstrate the smallest hydrogel-based PCs, responsive hydrogel-based photonic nanochains with high-resolution and real-time response, by developing a general hydrogen bond-guided template polymerization method. A variety of mechanically separated stimuli-responsive hydrogel-based photonic nanochains have been obtained in a large scale including those responding to pH, solvent, and temperature. Each of them has a submicrometer diameter and is composed of individual one-dimensional periodic structure of magnetic particles locked by a tens-of-nanometer-thick peapod-like responsive hydrogel shell. Taking the pH-responsive hydrogel-based photonic nanochains, for example, pH-induced hydrogel volume change notably alters the nanochain length, resulting in a significant variation of the structural color. The submicrometer size endows the nanochains with improved resolution and response time by 2-3 orders of magnitude than the previous counterparts. Our results for the first time validate the feasibility of using structural colors for microenvironment sensing and imaging and may further promote the applications of responsive PCs, such as in displays and printing.

Inter-annual and spatial variability of Hamon potential evapotranspiration model coefficients

USGS Publications Warehouse

McCabe, Gregory J.; Hay, Lauren E.; Bock, Andy; Markstrom, Steven L.; Atkinson, R. Dwight

2015-01-01

Monthly calibrated values of the Hamon PET coefficient (C) are determined for 109,951 hydrologic response units (HRUs) across the conterminous United States (U.S.). The calibrated coefficient values are determined by matching calculated mean monthly Hamon PET to mean monthly free-water surface evaporation. For most locations and months the calibrated coefficients are larger than the standard value reported by Hamon. The largest changes in the coefficients were for the late winter/early spring and fall months, whereas the smallest changes were for the summer months. Comparisons of PET computed using the standard value of C and computed using calibrated values of C indicate that for most of the conterminous U.S. PET is underestimated using the standard Hamon PET coefficient, except for the southeastern U.S.

Design tradeoffs for trend assessment in aquatic biological monitoring programs

USGS Publications Warehouse

Gurtz, Martin E.; Van Sickle, John; Carlisle, Daren M.; Paulsen, Steven G.

2013-01-01

Assessments of long-term (multiyear) temporal trends in biological monitoring programs are generally undertaken without an adequate understanding of the temporal variability of biological communities. When the sources and levels of variability are unknown, managers cannot make informed choices in sampling design to achieve monitoring goals in a cost-effective manner. We evaluated different trend sampling designs by estimating components of both short- and long-term variability in biological indicators of water quality in streams. Invertebrate samples were collected from 32 sites—9 urban, 6 agricultural, and 17 relatively undisturbed (reference) streams—distributed throughout the United States. Between 5 and 12 yearly samples were collected at each site during the period 1993–2008, plus 2 samples within a 10-week index period during either 2007 or 2008. These data allowed calculation of four sources of variance for invertebrate indicators: among sites, among years within sites, interaction among sites and years (site-specific annual variation), and among samples collected within an index period at a site (residual). When estimates of these variance components are known, changes to sampling design can be made to improve trend detection. Design modifications that result in the ability to detect the smallest trend with the fewest samples are, from most to least effective: (1) increasing the number of years in the sampling period (duration of the monitoring program), (2) decreasing the interval between samples, and (3) increasing the number of repeat-visit samples per year (within an index period). This order of improvement in trend detection, which achieves the greatest gain for the fewest samples, is the same whether trends are assessed at an individual site or an average trend of multiple sites. In multiple-site surveys, increasing the number of sites has an effect similar to that of decreasing the sampling interval; the benefit of adding sites is greater when a new set of different sites is selected for each sampling effort than when the same sites are sampled each time. Understanding variance components of the ecological attributes of interest can lead to more cost-effective monitoring designs to detect trends.

Smallest fullerene-like silicon cage stabilized by a V{sub 2} unit

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

Xu, Hong-Guang, E-mail: xuhong@iccas.ac.cn, E-mail: zhengwj@iccas.ac.cn; Kong, Xiang-Yu; Deng, Xiao-Jiao

We conducted a combined anion photoelectron spectroscopy and density functional theory study on V{sub 2}Si{sub 20} cluster. Our results show that the V{sub 2}Si{sub 20} cluster has an elongated dodecahedron cage structure with a V{sub 2} unit encapsulated inside the cage. It is the smallest fullerene-like silicon cage and can be used as building block to make cluster-assembled materials, such as pearl-chain style nanowires.

City of Troitsk and Sooty Snow, Chelyabinsk, CIS

NASA Technical Reports Server (NTRS)

1992-01-01

This view shows the industrial pollution around the Siberian city of Troitsk (54.0N, 61.0E). Troitsk is the smallest of a group of three heavy industrial cities east of the Urals, the others being Magnitogorsk and Chelyabinsk. All have been cited as being some of the worst industrial polluted cities in the CIS. Despite being the smallest of the three, Troitsk has the largest area of soot blackened snow. Respiratory diseases among the citizens are chronic.

A quantitative study of ramped radio frequency, magnetization transfer, and slab thickness in three-dimensional time-of-flight magnetic resonance angiography in a patient population.

PubMed

Goodrich, K C; Blatter, D D; Parker, D L; Du, Y P; Meyer, K J; Bernstein, M A

1996-06-01

The authors compare the effectiveness of various magnetic resonance (MR) angiography acquisition strategies in enhancing the visibility of small intracranial vessels. Blood vessel contrast-to-noise ratio (CNR) in time-of-flight MR angiography was studied as a function of vessel size and several selectable imaging parameters. Contrast-to-noise measurements were made on 257 vessel segments ranging in size from 0.3 mm to 4.2 mm in patients who recently had undergone intraarterial cerebral angiography. Imaging parameters studied included magnetization transfer, spatially variable radio frequency (RF) pulse profile (ramped RF), and imaging slab thickness. The combination of thin slabs (16 slices/slab), ramped RF, and magnetization transfer resulted in the highest CNR for all but the smallest vessel sizes. The smallest vessels (< 0.5 mm) had the highest CNR, using the thick slab (64 slices/slab) with ramped RF and magnetization transfer. Magnetization transfer always improved vessel CNR, but the improvement diminished as the slab thickness was reduced. The CNR increased with a decrease in slab thickness for all but the smallest vessel sizes. Overall, the results provide a quantitative demonstration that inflow enhancement of blood is reduced for small vessels. Thus, whereas magnetization transfer is important at all vessel sizes, it becomes the primary factor in improving the visibility of the smallest vessels.

Tumor necrosis factor inhibitor therapy but not standard therapy is associated with resolution of erosion in the sacroiliac joints of patients with axial spondyloarthritis

PubMed Central

2014-01-01

Introduction Radiography is an unreliable and insensitive tool for the assessment of structural lesions in the sacroiliac joints (SIJ). Magnetic resonance imaging (MRI) detects a wider spectrum of structural lesions but has undergone minimal validation in prospective studies. The Spondyloarthritis Research Consortium of Canada (SPARCC) MRI Sacroiliac Joint (SIJ) Structural Score (SSS) assesses a spectrum of structural lesions (erosion, fat metaplasia, backfill, ankylosis) and its potential to discriminate between therapies requires evaluation. Methods The SSS score assesses five consecutive coronal slices through the cartilaginous portion of the joint on T1-weighted sequences starting from the transitional slice between cartilaginous and ligamentous portions of the joint. Lesions are scored dichotomously (present/absent) in SIJ quadrants (fat metaplasia, erosion) or halves (backfill, ankylosis). Two readers independently scored 147 pairs (baseline, 2 years) of scans from a prospective cohort of patients with SpA who received either standard (n = 69) or tumor necrosis factor alpha (TNFα) inhibitor (n = 78) therapy. Smallest detectable change (SDC) was calculated using analysis of variance (ANOVA), discrimination was assessed using Guyatt’s effect size, and treatment group differences were assessed using t-tests and the Mann–Whitney test. We identified baseline demographic and structural damage variables associated with change in SSS score by univariate analysis and analyzed the effect of treatment by multivariate stepwise regression adjusted for severity of baseline structural damage and demographic variables. Results A significant increase in mean SSS score for fat metaplasia (P = 0.017) and decrease in mean SSS score for erosion (P = 0.017) was noted in anti-TNFα treated patients compared to those on standard therapy. Effect size for this change in SSS fat metaplasia and erosion score was moderate (0.5 and 0.6, respectively). Treatment and baseline SSS score for erosion were independently associated with change in SSS erosion score (β = 1.75, P = 0.003 and β = 0.40, P < 0.0001, respectively). Change in ASDAS (β = −0.46, P = 0.006), SPARCC MRI SIJ inflammation (β = −0.077, P = 0.019), and baseline SSS score for fat metaplasia (β = 0.085, P = 0.034) were independently associated with new fat metaplasia. Conclusion The SPARCC SSS method for assessment of structural lesions has discriminative capacity in demonstrating significantly greater reduction in erosion and new fat metaplasia in patients receiving anti-TNFα therapy. PMID:24755322

[Changes of agroecosystem services value under effects of land consolidation].

PubMed

Zhang, Zhen; Gao, Jin-Quan; Wei, Chao-Fu

2010-03-01

This paper quantitatively described the changes of agroecosystem functions before (2003) and after (2007) the implementation of Gaolong land consolidation project in Hechuan of Chongqing. Engineering design and shadow price were integrated to quantify the effects of the project on the functions, and cost-benefit analysis was used to further explain the economic meanings of the functions, and to analyze the changes of the agroecosystem services value under effects of the project. Compared with that before the land consolidation, the agroecosystem services value after the land consolidation was somewhat improved, with the largest increment of nutrient cycling function and the smallest change of soil conservation function. In the implementation of the project, the changes of the agroecosystem services value induced by farmland water conservancy, field road building, and land-leveling engineering mainly manifested in the change of disturbance function. From the 7th to 35th year after the project, the cost benefit would have a rapid increase, and tended to be stable after then, giving a weak ecological pressure and little services value loss, and benefiting the improvement of regional ecological environment.

Cause-specific sickness absence trends by occupational class and industrial sector in the context of recent labour market changes: a Finnish panel data study

PubMed Central

Leinonen, Taina; Viikari-Juntura, Eira; Husgafvel-Pursiainen, Kirsti; Solovieva, Svetlana

2018-01-01

Objectives We aimed to provide previously unestablished information on population-based differences in cause-specific sickness absence trends between occupational classes and further between four large industrial sectors within the different occupational classes while controlling for other socioeconomic factors and employment patterns. We focused on the period 2005–2013, during which the labour market underwent large economic and structural changes in many countries. Design Register-based panel data study. Setting Large representative datasets on Finnish wage earners aged 25–59 years. Outcome measure Annual risk of sickness absence (>10 working days) based on repeated logistic regression. Results Between 2005 and 2013, the proportion of employees with sickness absence decreased. Occupational class differences in sickness absence trends varied by disease group. Overall, the decrease in absences was smallest among lower non-manual employees. Sickness absence levels were highest in the health and social work sector and in the manufacturing sector within the non-manual and manual classes, respectively. Absences due to musculoskeletal diseases decreased temporarily during the peak of the economic recession in 2009, particularly in the manufacturing sector within the manual class. The decrease in absences due to musculoskeletal diseases was smallest in the trade sector within the lower occupational classes. Overall, education, income and employment patterns partly explained the differences in the absence levels, but not in the trends. Conclusions We found a complex interplay between the associations of occupational class and industrial sector with sickness absence trends. During the economic recession, absences due to musculoskeletal diseases decreased temporarily in a segment of wage earners who were known to have been hit hard by the recession. However, the trend differences were not explained by the measured structural changes in the characteristics of the study population. Both occupational class and industrial sector should be taken into account when tackling problems of work disability. PMID:29627810

The effect of amphiphilic polymers with a continuous amphiphilicity profile on the membrane properties in a bicontinuous microemulsions studied by neutron scattering

NASA Astrophysics Data System (ADS)

Klemmer, Helge F. M.; Frielinghaus, Henrich; Allgaier, Jürgen; Ohl, Michael; Holderer, Olaf

2017-06-01

Microemulsion systems consisting of oil, water and surfactant have been studied with neutron scattering techniques. The amount of surfactant needed to form a microemulsion can be dramatically reduced by the addition of small amounts of amphiphilic block copolymers (boosting effect). Here, we studied the influence of block copolymers with gradually changing amphiphilicity from hydrophilic to hydrophobic. Small angle neutron scattering (SANS), neutron spin echo spectroscopy (NSE) and phase diagram measurements in combination give access to the elastic properties of the membrane. The underlying NSE experiments for this interpretation rely on smallest changes of the relaxation curves (of ca. 1% steps) for still small changes of the bending rigidity (of ca. 10% steps). This high reliability of the experiments conducted at the SNS-NSE displays the accuracy of the instrument itself and the latest developments of the evaluation software, which were necessary to interpret such tiny changes of the bending rigidity reliably.

Some distinguishing characteristics of contour and texture phenomena in images

NASA Technical Reports Server (NTRS)

Jobson, Daniel J.

1992-01-01

The development of generalized contour/texture discrimination techniques is a central element necessary for machine vision recognition and interpretation of arbitrary images. Here, the visual perception of texture, selected studies of texture analysis in machine vision, and diverse small samples of contour and texture are all used to provide insights into the fundamental characteristics of contour and texture. From these, an experimental discrimination scheme is developed and tested on a battery of natural images. The visual perception of texture defined fine texture as a subclass which is interpreted as shading and is distinct from coarse figural similarity textures. Also, perception defined the smallest scale for contour/texture discrimination as eight to nine visual acuity units. Three contour/texture discrimination parameters were found to be moderately successful for this scale discrimination: (1) lightness change in a blurred version of the image, (2) change in lightness change in the original image, and (3) percent change in edge counts relative to local maximum.

Phase change thermal energy storage methods for combat vehicles, phase 1

NASA Astrophysics Data System (ADS)

Lynch, F. E.

1986-06-01

Three alternative cooling methods, based on latent heat absorption during phase changes, were studied for potential use in combat vehicle microclimate temperature control. Metal hydrides absorb heat as they release hydrogen gas. Plastic crystals change from one solid phase to another, absorbing heat in the process. Liquid air boils at cryogenic temperature and absorbs additional sensible heat as the cold gas mixes with the microclimate air flow. System designs were prepared for each of the three microclimate cooling concepts. These designs provide details about the three phase change materials, their containers and the auxiliary equipment needed to implement each option onboard a combat vehicle. The three concepts were compared on the basis of system mass, system volume and the energy required to regenerate them after use. Metal hydrides were found to be the lightest and smallest option by a large margin. The energy needed to regenerate a hydride thermal storage system can be extracted from the vehicle's exhaust gases.

Measurement properties of the Dizziness Handicap Inventory by cross-sectional and longitudinal designs

PubMed Central

2009-01-01

Background The impact of dizziness on quality of life is often assessed by the Dizziness Handicap Inventory (DHI), which is used as a discriminate and evaluative measure. The aim of the present study was to examine reliability and validity of a translated Norwegian version (DHI-N), also examining responsiveness to important change in the construct being measured. Methods Two samples (n = 92 and n = 27) included participants with dizziness of mainly vestibular origin. A cross-sectional design was used to examine the factor structure (exploratory factor analysis), internal consistency (Cronbach's α), concurrent validity (Pearson's product moment correlation r), and discriminate ability (ROC curve analysis). Longitudinal designs were used to examine test-retest reliability (intraclass correlation coefficient (ICC) statistics, smallest detectable difference (SDD)), and responsiveness (Pearson's product moment correlation, ROC curve analysis; area under the ROC curve (AUC), and minimally important change (MIC)). The DHI scores range from 0 to 100. Results Factor analysis revealed a different factor structure than the original DHI, resulting in dismissal of subscale scores in the DHI-N. Acceptable internal consistency was found for the total scale (α = 0.95). Concurrent correlations between the DHI-N and other related measures were moderate to high, highest with Vertigo Symptom Scale-short form-Norwegian version (r = 0.69), and lowest with preferred gait (r = - 0.36). The DHI-N demonstrated excellent ability to discriminate between participants with and without 'disability', AUC being 0.89 and best cut-off point = 29 points. Satisfactory test-retest reliability was demonstrated, and the change for an individual should be ≥ 20 DHI-N points to exceed measurement error (SDD). Correlations between change scores of DHI-N and other self-report measures of functional health and symptoms were high (r = 0.50 - 0.57). Responsiveness of the DHI-N was excellent, AUC = 0.83, discriminating between self-perceived 'improved' versus 'unchanged' participants. The MIC was identified as 11 DHI-N points. Conclusions The DHI-N total scale demonstrated satisfactory measurement properties. This is the first study that has addressed and demonstrated responsiveness to important change of the DHI, and provided values of SDD and MIC to help interpret change scores. PMID:20025754

An R-peak detection method that uses an SVD filter and a search back system.

PubMed

Jung, Woo-Hyuk; Lee, Sang-Goog

2012-12-01

In this paper, we present a method for detecting the R-peak of an ECG signal by using an singular value decomposition (SVD) filter and a search back system. The ECG signal was detected in two phases: the pre-processing phase and the decision phase. The pre-processing phase consisted of the stages for the SVD filter, Butterworth High Pass Filter (HPF), moving average (MA), and squaring, whereas the decision phase consisted of a single stage that detected the R-peak. In the pre-processing phase, the SVD filter removed noise while the Butterworth HPF eliminated baseline wander. The MA removed the remaining noise of the signal that had gone through the SVD filter to make the signal smooth, and squaring played a role in strengthening the signal. In the decision phase, the threshold was used to set the interval before detecting the R-peak. When the latest R-R interval (RRI), suggested by Hamilton et al., was greater than 150% of the previous RRI, the method of detecting the R-peak in such an interval was modified to be 150% or greater than the smallest interval of the two most latest RRIs. When the modified search back system was used, the error rate of the peak detection decreased to 0.29%, compared to 1.34% when the modified search back system was not used. Consequently, the sensitivity was 99.47%, the positive predictivity was 99.47%, and the detection error was 1.05%. Furthermore, the quality of the signal in data with a substantial amount of noise was improved, and thus, the R-peak was detected effectively. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Corneal Power Distribution and Functional Optical Zone Following Small Incision Lenticule Extraction for Myopia.

PubMed

Qian, Yishan; Huang, Jia; Zhou, Xingtao; Hanna, Rewais Benjamin

2015-08-01

To evaluate corneal power distribution using the ray tracing method (corneal power) in eyes undergoing small incision lenticule extraction (SMILE) surgery and compare the functional optical zone with two lenticular sizes. This retrospective study evaluated 128 patients who underwent SMILE for the correction of myopia and astigmatism with a lenticular diameter of 6.5 mm (the 6.5-mm group) and 6.2 mm (the 6.2-mm group). The data include refraction, correction, and corneal power obtained via a Scheimpflug camera from the pupil center to 8 mm. The surgically induced changes in corneal power (Δcorneal power) were compared to correction and Δrefraction. The functional optical zone was defined as the largest ring diameter when the difference between the ring power and the pupil center power was 1.50 diopters or less. The functional optical zone was compared between two lenticular diameter groups. Corneal power distribution was measured by the ray tracing method. In the 6.5-mm group (n=100), Δcorneal power at 5 mm showed the smallest difference from Δrefraction and Δcorneal power at 0 mm exhibited the smallest difference from correction. In the 6.2-mm group (n=28), Δcorneal power at 2 mm displayed the lowest dissimilarity from Δrefraction and Δcorneal power at 4 mm demonstrated the lowest dissimilarity from correction. There was no significant difference between the mean postoperative functional optical zones in either group when their spherical equivalents were matched. Total corneal refactive power can be used in the evaluation of surgically induced changes following SMILE. A lenticular diameter of 6.2 mm should be recommended for patients with high myopia because there is no functional difference in the optical zone. Copyright 2015, SLACK Incorporated.

Changes in performance over time while learning to use a myoelectric prosthesis

PubMed Central

2014-01-01

Background Training increases the functional use of an upper limb prosthesis, but little is known about how people learn to use their prosthesis. The aim of this study was to describe the changes in performance with an upper limb myoelectric prosthesis during practice. The results provide a basis to develop an evidence-based training program. Methods Thirty-one able-bodied participants took part in an experiment as well as thirty-one age- and gender-matched controls. Participants in the experimental condition, randomly assigned to one of four groups, practiced with a myoelectric simulator for five sessions in a two-weeks period. Group 1 practiced direct grasping, Group 2 practiced indirect grasping, Group 3 practiced fixating, and Group 4 practiced a combination of all three tasks. The Southampton Hand Assessment Procedure (SHAP) was assessed in a pretest, posttest, and two retention tests. Participants in the control condition performed SHAP two times, two weeks apart with no practice in between. Compressible objects were used in the grasping tasks. Changes in end-point kinematics, joint angles, and grip force control, the latter measured by magnitude of object compression, were examined. Results The experimental groups improved more on SHAP than the control group. Interestingly, the fixation group improved comparable to the other training groups on the SHAP. Improvement in global position of the prosthesis leveled off after three practice sessions, whereas learning to control grip force required more time. The indirect grasping group had the smallest object compression in the beginning and this did not change over time, whereas the direct grasping and the combination group had a decrease in compression over time. Moreover, the indirect grasping group had the smallest grasping time that did not vary over object rigidity, while for the other two groups the grasping time decreased with an increase in object rigidity. Conclusions A training program should spend more time on learning fine control aspects of the prosthetic hand during rehabilitation. Moreover, training should start with the indirect grasping task that has the best performance, which is probably due to the higher amount of useful information available from the sound hand. PMID:24568148

Designing clinical trials of interventions for mobility disability: results from the lifestyle interventions and independence for elders pilot (LIFE-P) trial.

PubMed

Espeland, Mark A; Gill, Thomas M; Guralnik, Jack; Miller, Michael E; Fielding, Roger; Newman, Anne B; Pahor, Marco

2007-11-01

Clinical trials to assess interventions for mobility disability are critically needed; however, data for efficiently designing such trials are lacking. Results are described from a pilot clinical trial in which 424 volunteers aged 70-89 years were randomly assigned to one of two interventions-physical activity or a healthy aging education program-and followed for a planned minimum of 12 months. We evaluated the longitudinal distributions of four standardized outcomes to contrast how they may serve as primary outcomes of future clinical trials: ability to walk 400 meters, ability to walk 4 meters in < or =10 seconds, a physical performance battery, and a questionnaire focused on physical function. Changes in all four outcomes were interrelated over time. The ability to walk 400 meters as a dichotomous outcome provided the smallest sample size projections (i.e., appeared to be the most efficient outcome). It loaded most heavily on the underlying latent variable in structural equation modeling with a weight of 80%. A 4-year trial based on the outcome of the 400-meter walk is projected to require N = 962-2234 to detect an intervention effect of 30%-20% with 90% power. Future clinical trials of interventions designed to influence mobility disability may have greater efficiency if they adopt the ability to complete a 400-meter walk as their primary outcome.

E. coli derived Von Willebrand Factor-A2 domain FRET proteins that quantify ADAMTS13 activity

PubMed Central

Dayananda, Kannayakanahalli M.; Gogia, Shobhit; Neelamegham, Sriram

2010-01-01

The cleavage of the A2-domain of Von Willebrand Factor (VWF) by the metalloprotease ADAMTS13 regulates VWF size and platelet thrombosis rates. Reduction or inhibition of this enzyme activity leads to thrombotic thrombocytopenic purpura (TTP). We generated a set of novel molecules called VWF-A2 FRET proteins’, where variants of YFP (Venus) and CFP (Cerulean) flank either the entire VWF-A2 domain (175 amino acids) or truncated fragments (141, 113, 77 amino acids) of this domain. These proteins were expressed in E. coli in soluble form, and they exhibited Fluorescence/Förster Resonance Energy Transfer (FRET) properties. Results show that introduction of Venus/Cerulean itself did not alter the ability of VWF-A2 to undergo ADAMTS13 mediated cleavage. The smallest FRET protein, XS-VWF, detected plasma ADAMTS13 activity down to 10% of normal levels. Tests of acquired and inherited TTP could be completed within 30 min. VWF-A2 conformation changed progressively, and not abruptly, upon increasing urea concentration. While proteins with 77 and 113 VWF-A2 residues were cleaved in the absence of denaturant, 4M urea was required for the efficient cleavage of larger constructs. Overall, VWF-A2 FRET proteins can be applied both for the rapid diagnosis of plasma ADAMTS13 activity, and as a tool to study VWF-A2 conformation dynamics. PMID:21146487

Revival of the Magnetar PSR J1622–4950: Observations with MeerKAT, Parkes, XMM-Newton, Swift, Chandra, and NuSTAR

NASA Astrophysics Data System (ADS)

Camilo, F.; Scholz, P.; Serylak, M.; Buchner, S.; Merryfield, M.; Kaspi, V. M.; Archibald, R. F.; Bailes, M.; Jameson, A.; van Straten, W.; Sarkissian, J.; Reynolds, J. E.; Johnston, S.; Hobbs, G.; Abbott, T. D.; Adam, R. M.; Adams, G. B.; Alberts, T.; Andreas, R.; Asad, K. M. B.; Baker, D. E.; Baloyi, T.; Bauermeister, E. F.; Baxana, T.; Bennett, T. G. H.; Bernardi, G.; Booisen, D.; Booth, R. S.; Botha, D. H.; Boyana, L.; Brederode, L. R. S.; Burger, J. P.; Cheetham, T.; Conradie, J.; Conradie, J. P.; Davidson, D. B.; De Bruin, G.; de Swardt, B.; de Villiers, C.; de Villiers, D. I. L.; de Villiers, M. S.; de Villiers, W.; De Waal, C.; Dikgale, M. A.; du Toit, G.; du Toit, L. J.; Esterhuyse, S. W. P.; Fanaroff, B.; Fataar, S.; Foley, A. R.; Foster, G.; Fourie, D.; Gamatham, R.; Gatsi, T.; Geschke, R.; Goedhart, S.; Grobler, T. L.; Gumede, S. C.; Hlakola, M. J.; Hokwana, A.; Hoorn, D. H.; Horn, D.; Horrell, J.; Hugo, B.; Isaacson, A.; Jacobs, O.; Jansen van Rensburg, J. P.; Jonas, J. L.; Jordaan, B.; Joubert, A.; Joubert, F.; Józsa, G. I. G.; Julie, R.; Julius, C. C.; Kapp, F.; Karastergiou, A.; Karels, F.; Kariseb, M.; Karuppusamy, R.; Kasper, V.; Knox-Davies, E. C.; Koch, D.; Kotzé, P. P. A.; Krebs, A.; Kriek, N.; Kriel, H.; Kusel, T.; Lamoor, S.; Lehmensiek, R.; Liebenberg, D.; Liebenberg, I.; Lord, R. T.; Lunsky, B.; Mabombo, N.; Macdonald, T.; Macfarlane, P.; Madisa, K.; Mafhungo, L.; Magnus, L. G.; Magozore, C.; Mahgoub, O.; Main, J. P. L.; Makhathini, S.; Malan, J. A.; Malgas, P.; Manley, J. R.; Manzini, M.; Marais, L.; Marais, N.; Marais, S. J.; Maree, M.; Martens, A.; Matshawule, S. D.; Matthysen, N.; Mauch, T.; McNally, L. D.; Merry, B.; Millenaar, R. P.; Mjikelo, C.; Mkhabela, N.; Mnyandu, N.; Moeng, I. T.; Mokone, O. J.; Monama, T. E.; Montshiwa, K.; Moss, V.; Mphego, M.; New, W.; Ngcebetsha, B.; Ngoasheng, K.; Niehaus, H.; Ntuli, P.; Nzama, A.; Obies, F.; Obrocka, M.; Ockards, M. T.; Olyn, C.; Oozeer, N.; Otto, A. J.; Padayachee, Y.; Passmoor, S.; Patel, A. A.; Paula, S.; Peens-Hough, A.; Pholoholo, B.; Prozesky, P.; Rakoma, S.; Ramaila, A. J. T.; Rammala, I.; Ramudzuli, Z. R.; Rasivhaga, M.; Ratcliffe, S.; Reader, H. C.; Renil, R.; Richter, L.; Robyntjies, A.; Rosekrans, D.; Rust, A.; Salie, S.; Sambu, N.; Schollar, C. T. G.; Schwardt, L.; Seranyane, S.; Sethosa, G.; Sharpe, C.; Siebrits, R.; Sirothia, S. K.; Slabber, M. J.; Smirnov, O.; Smith, S.; Sofeya, L.; Songqumase, N.; Spann, R.; Stappers, B.; Steyn, D.; Steyn, T. J.; Strong, R.; Struthers, A.; Stuart, C.; Sunnylall, P.; Swart, P. S.; Taljaard, B.; Tasse, C.; Taylor, G.; Theron, I. P.; Thondikulam, V.; Thorat, K.; Tiplady, A.; Toruvanda, O.; van Aardt, J.; van Balla, T.; van den Heever, L.; van der Byl, A.; van der Merwe, C.; van der Merwe, P.; van Niekerk, P. C.; van Rooyen, R.; van Staden, J. P.; van Tonder, V.; van Wyk, R.; Wait, I.; Walker, A. L.; Wallace, B.; Welz, M.; Williams, L. P.; Xaia, B.; Young, N.; Zitha, S.

2018-04-01

New radio (MeerKAT and Parkes) and X-ray (XMM-Newton, Swift, Chandra, and NuSTAR) observations of PSR J1622–4950 indicate that the magnetar, in a quiescent state since at least early 2015, reactivated between 2017 March 19 and April 5. The radio flux density, while variable, is approximately 100× larger than during its dormant state. The X-ray flux one month after reactivation was at least 800× larger than during quiescence, and has been decaying exponentially on a 111 ± 19 day timescale. This high-flux state, together with a radio-derived rotational ephemeris, enabled for the first time the detection of X-ray pulsations for this magnetar. At 5%, the 0.3–6 keV pulsed fraction is comparable to the smallest observed for magnetars. The overall pulsar geometry inferred from polarized radio emission appears to be broadly consistent with that determined 6–8 years earlier. However, rotating vector model fits suggest that we are now seeing radio emission from a different location in the magnetosphere than previously. This indicates a novel way in which radio emission from magnetars can differ from that of ordinary pulsars. The torque on the neutron star is varying rapidly and unsteadily, as is common for magnetars following outburst, having changed by a factor of 7 within six months of reactivation.

A Microglitch in the Millisecond Pulsar PSR B1821-24 in M28

NASA Astrophysics Data System (ADS)

Cognard, Ismaël; Backer, Donald C.

2004-09-01

We report on the observation of a very small glitch observed for the first time in a millisecond pulsar, PSR B1821-24, located in the globular cluster M28. Timing observations were mainly conducted with the Nançay radio telescope (France), and confirmation comes from the 140 ft radio telescope at Green Bank and the new Green Bank Telescope data. This event is characterized by a rotation frequency step of 3 nHz, or 10-11 in fractional frequency change, along with a short duration limited to a few days or a week. A marginally significant frequency derivative step was also found. This glitch follows the main characteristics of those in the slow-period pulsars but is 2 orders of magnitude smaller than the smallest ever recorded. Such an event must be very rare for millisecond pulsars since no other glitches have been detected when the cumulated number of years of millisecond pulsar timing observations up to 2001 is around 500 for all these objects. However, pulsar PSR B1821-24 is one of the youngest among the old recycled ones, and there is likely a correlation between age, or a related parameter, and timing noise. While this event happens on a much smaller scale, the required adjustment of the star to a new equilibrium figure as it spins down is a likely common cause for all glitches.

Fabrication of Nanocomposites of SnO2 and MgAl2O4 for Gas Sensing Applications

NASA Astrophysics Data System (ADS)

Nithyavathy, N.; Arunmetha, S.; Vinoth, M.; Sriram, G.; Rajendran, V.

2016-04-01

Simple solid-state and sol-gel routes have been used to synthesize nanocomposites of tin oxide and magnesium aluminate at calcination temperature of 900 K for gas sensing applications. The effects of the surface structure of magnesium aluminate on the gas response for different concentrations of tin oxide addition were investigated for potential use in gas sensors. (SnO2) x doped in small amounts x into magnesium aluminate resulted in three nanocomposite samples MAS0.25, MAS0.50, and MAS0.75 for x = 0.25, 0.50, and 0.75, respectively, plus MgAl2O4 (MA) for x = 0. The response to different pressures of gases such as oxygen (O2), carbon monoxide (CO), and ethanol (C2H5OH) was quantitatively analyzed for all samples at different operating temperatures. The temperature was varied linearly by increasing the supply to a heating pad mounted below the sensor sample, regardless of the gas pressure inside the chamber. All the sample materials showed good response at different gas pressures (1 bar to 2 bar) and operating temperatures (300 K to 600 K). It was noted that the composite samples showed enhanced and fast response to gases, at both lower and higher operating temperatures, with detection of even the smallest change in gas pressure.

Phenotypic plasticity in the spawning traits of bigheaded carp (Hypophthalmichthys spp.) in novel ecosystems

USGS Publications Warehouse

Coulter, Alison A.; Keller, Doug; Amberg, Jon J.; Bailey, Elizabeth J.; Goforth, Reuben R.

2013-01-01

1. Bigheaded carp, including both silver (Hypophthalmichthys molitrix) and bighead (H. nobilis) carp, are successful invasive fishes that threaten global freshwater biodiversity. High phenotypic plasticity probably contributes to their success in novel ecosystems, although evidence of plasticity in several spawning traits has hitherto been largely anecdotal or speculative. 2. We collected drifting eggs from a Midwestern U.S.A. river from June to September 2011 and from April to June 2012 to investigate the spawning traits of bigheaded carp in novel ecosystems. 3. Unlike reports from the native range, the presence of drifting bigheaded carp eggs was not related to changes in hydrological regime or mean daily water temperature. Bigheaded carp also exhibited protracted spawning, since we found drifting eggs throughout the summer and as late as 1 September 2011. Finally, we detected bigheaded carp eggs in a river reach where the channel is c. 30 m wide with a catchment area of 4579 km2, the smallest stream in which spawning has yet been documented. 4. Taken with previous observations of spawning traits that depart from those observed within the native ranges of both bighead and silver carp, our findings provide direct evidence that bigheaded carp exhibit plastic spawning traits in novel ecosystems that may facilitate invasion and establishment in a wider range of river conditions than previously envisaged.

Multiwavelength Monitoring of the Enigmatic Narrow-Line Seyfert 1 PMN J0948 0022 in March-July 2009

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

Abdo, A.A.; /Naval Research Lab, Wash., D.C. /Federal City Coll.; Ackermann, M.

Following the recent discovery of {gamma} rays from the radio-loud narrow-line Seyfert 1 galaxy PMN J0948+0022 (z = 0.5846), we started a multiwavelength campaign from radio to {gamma} rays, which was carried out between the end of 2009 March and the beginning of July. The source displayed activity at all the observed wavelengths: a general decreasing trend from optical to {gamma}-ray frequencies was followed by an increase of radio emission after less than two months from the peak of the {gamma}-ray emission. The largest flux change, about a factor of about 4, occurred in the X-ray band. The smallest wasmore » at ultraviolet and near-infrared frequencies, where the rate of the detected photons dropped by a factor 1.6-1.9. At optical wavelengths, where the sampling rate was the highest, it was possible to observe day scale variability, with flux variations up to a factor of about 3. The behavior of PMN J0948+0022 observed in this campaign and the calculated power carried out by its jet in the form of protons, electrons, radiation, and magnetic field are quite similar to that of blazars, specifically of flat-spectrum radio quasars. These results confirm the idea that radio-loud narrow-line Seyfert 1 galaxies host relativistic jets with power similar to that of average blazars.« less

Hollow waveguides for the transmission of quantum cascade laser (QCL) energy for spectroscopic applications

NASA Astrophysics Data System (ADS)

Harrington, James A.; Bledt, Carlos M.; Kriesel, Jason M.

2011-03-01

Spectroscopy in the long-wave infrared (LWIR) wavelength region (8 to 12 μm) is useful for detecting trace chemical compounds, such as those indicative of weapons of mass destruction (WMD). To enable the development of field portable systems for anti-proliferation efforts, current spectroscopy systems need to be made more robust, convenient, and practical (e.g., miniaturized). Hollow glass waveguides have been used with a Quantum Cascade Laser source for the delivery of single-mode laser radiation from 9 to 10 μm. The lowest loss measured for a straight, 484 μm-bore guide was 0.44 dB/m at 10 μm. The smallest 300 μm-bore waveguide transmitted singlemode radiation even while bent to radii less than 30 cm.

Studies of ionic current rectification using polyethyleneimines coated glass nanopipettes.

PubMed

Liu, Shujuan; Dong, Yitong; Zhao, Wenbo; Xie, Xiang; Ji, Tianrong; Yin, Xiaohong; Liu, Yun; Liang, Zhongwei; Momotenko, Dmitry; Liang, Dehai; Girault, Hubert H; Shao, Yuanhua

2012-07-03

The modification of glass nanopipettes with polyethyleneimines (PEIs) has been successfully achieved by a relatively simple method, and the smallest tip opening is around 3 nm. Thus, in a much wider range of glass pipettes with radii from several nanometers to a few micrometers, the ion current rectification (ICR) phenomenon has been observed. The influences of different KCl concentrations, pH values, and tip radii on the ICR are investigated in detail. The sizes of PEIs have been determined by dynamic light scattering, and the effect of the sizes of PEIs for the modification, especially for a few nanometer-pipettes in radii, is also discussed. These findings systemically confirm and complement the theoretical model and provide a platform for possible selectively molecular detection and mimic biological ion channels.

[Early flat colorectal cancer].

PubMed

Castelletto, R H; Chiarenza, C; Ottino, A; Garay, M L

1991-01-01

We report three cases of flat early colorectal carcinoma which were detected during the examination of 51 surgical specimens of colorectal resection. Two of them were endoscopically diagnosed, but the smallest one was not seen in the luminal instrumental examination. From the bibliographic analysis and our own experience we deduce the importance of flat lesions in the development of early colorectal carcinoma, either originated from pre-existent adenoma or de novo. Flat variants of adenoma, and presumably flush or depressed ones, must be considered as important factors in the early sequence adenoma-cancer. An appropriate endoscopic equipment with employment of additional staining techniques (such as carmine indigo and methylene blue) and the correct investigation during inflation-deflation procedures facilitates the identification of small lesions, their eradication and prevention from advanced forms of colorectal carcinoma.

VLBI observations of the 0957 + 561 gravitational lens system

NASA Technical Reports Server (NTRS)

Gorenstein, M. V.; Falco, E. E.; Shapiro, I. I.; Bartel, N.; Bonometti, R. J.; Cohen, N. L.; Rogers, A. E. E.; Marcaide, J. M.; Clark, T. A.

1988-01-01

A series of VLBI observations of the gravitational lens system 0957 + 561 at a wavelength of 13 cm has yielded the positions of the A and B images, the relative magnification of their largest discernible radio structures, and the time variability of their smallest discernible radio structures. These observations have also allowed upper limits to be placed on the flux density of an expected third image. The positions and relative magnification of the A and B images provide new information with which to constrain models of the lens that forms the images. The detection of variations in the flux densities of the cores of A and B suggests that observations at shorter wavelengths may reveal superluminal motion, which may in turn provide a means to measure the relative time delay.

A century of general relativity: astrophysics and cosmology.

PubMed

Blandford, R D

2015-03-06

One hundred years after its birth, general relativity has become a highly successful physical theory in the sense that it has passed a large number of experimental and observational tests and finds extensive application to a wide variety of cosmic phenomena. It remains an active area of research as new tests are on the way, epitomized by the exciting prospect of detecting gravitational waves from merging black holes. General relativity is the essential foundation of the standard model of cosmology and underlies our description of the black holes and neutron stars that are ultimately responsible for the most powerful and dramatic cosmic sources. Its interface with physics on the smallest and largest scales will continue to provide fertile areas of investigation in its next century. Copyright © 2015, American Association for the Advancement of Science.

Dynamic speckle illumination wide-field reflection phase microscopy

PubMed Central

Choi, Youngwoon; Hosseini, Poorya; Choi, Wonshik; Dasari, Ramachandra R.; So, Peter T. C.; Yaqoob, Zahid

2014-01-01

We demonstrate a quantitative reflection-phase microscope based on time-varying speckle-field illumination. Due to the short spatial coherence length of the speckle field, the proposed imaging system features superior lateral resolution, 520 nm, as well as high-depth selectivity, 1.03 µm. Off-axis interferometric detection enables wide-field and single-shot imaging appropriate for high-speed measurements. In addition, the measured phase sensitivity of this method, which is the smallest measurable axial motion, is more than 40 times higher than that available using a transmission system. We demonstrate the utility of our method by successfully distinguishing the motion of the top surface from that of the bottom in red blood cells. The proposed method will be useful for studying membrane dynamics in complex eukaryotic cells. PMID:25361156

Searching For Vulcanoids

NASA Astrophysics Data System (ADS)

Campins, H.; Davis, D. R.; Weidenschilling, S. J.; Magee, M.

Vulcanoids are a hypothesized population of small asteroid-like bodies in orbits interior to that of Mercury. Their presence or absence would be an important test of cosmogonical theories. There are significant dynamical and thermodynamical constraints that restrict the search area roughly to the ecliptic in the range of 0.1 to 0.25 AU from the Sun. Previous searches rule out only bodies with radii greater than about 50--100 km. We estimate that with current technology a search with a limiting magnitude of 6 at 3.5 microns might be feasible. This limiting magnitude corresponds approximately to the smallest (1 km) objects expected to have survived in this region over the age of the solar system. If such a search were carried out, even the absence of detections would yield definitive results.

Comparison of the nuclear organiser region activity in four taxa of the family Canidae.

PubMed

Pieńkowska, A; Zagalska, M

2001-01-01

Four species of the family Canidae were cytogenetically studied. The activity of NORs was detected with the use of silver staining. The number of NORs was characteristic for a given karyotype. For the dog found on autosomes 7, 17, 20 and on sex chromosome (Y), for the racoon dog on autosomes 1, 4, 13 and on sex chromosome (Y), for the silver fox only on autosomes 8, 9, 13 and for the blue fox on autosomes 13, 15, 17, 18, 20 and 22. The results demonstrate that NOR activity is similar in all the analysed species of the Canidae. Simultaneously, NOR activity for a medium-sized chromosome pair is distinctly higher than for two other autosome pairs (the longest and the smallest pair). Considerable variability was observed within individuals.

Discovery of skin alkaloids in a miniaturized eleutherodactylid frog from Cuba.

PubMed

Rodríguez, Ariel; Poth, Dennis; Schulz, Stefan; Vences, Miguel

2011-06-23

Four phylogenetically independent lineages of frogs are currently known to sequester lipid-soluble skin alkaloids for which a dietary source has been demonstrated. We report here a remarkable fifth such instance, in Eleutherodactylus iberia and Eleutherodactylus orientalis, two species of miniaturized frogs of the family Eleutherodactylidae from Cuba. Six pumiliotoxins and two indolizidines were found in E. iberia, one of the smallest frogs in the world and characterized by a contrasting colour pattern for which we hypothesize an aposematic function. Analyses of stomach content indicated a numerical prevalence of mites with an important proportion of oribatids-a group of arthropods known to contain one of the pumiliotoxins detected in E. iberia. This suggests that miniaturization and specialization to small prey may have favoured the acquisition of dietary skin alkaloids in these amphibians.

Comparative Evaluation of Dimensional Accuracy of Elastomeric Impression Materials when Treated with Autoclave, Microwave, and Chemical Disinfection.

PubMed

Kamble, Suresh S; Khandeparker, Rakshit Vijay; Somasundaram, P; Raghav, Shweta; Babaji, Rashmi P; Varghese, T Joju

2015-09-01

Impression materials during impression procedure often get infected with various infectious diseases. Hence, disinfection of impression materials with various disinfectants is advised to protect the dental team. Disinfection can alter the dimensional accuracy of impression materials. The present study was aimed to evaluate the dimensional accuracy of elastomeric impression materials when treated with different disinfectants; autoclave, chemical, and microwave method. The impression materials used for the study were, dentsply aquasil (addition silicone polyvinylsiloxane syringe and putty), zetaplus (condensation silicone putty and light body), and impregum penta soft (polyether). All impressions were made according to manufacturer's instructions. Dimensional changes were measured before and after different disinfection procedures. Dentsply aquasil showed smallest dimensional change (-0.0046%) and impregum penta soft highest linear dimensional changes (-0.026%). All the tested elastomeric impression materials showed some degree of dimensional changes. The present study showed that all the disinfection procedures produce minor dimensional changes of impression material. However, it was within American Dental Association specification. Hence, steam autoclaving and microwave method can be used as an alternative method to chemical sterilization as an effective method.

RECOVERY ACT: MULTIMODAL IMAGING FOR SOLAR CELL MICROCRACK DETECTION

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

Janice Hudgings; Lawrence Domash

2012-02-08

Undetected microcracks in solar cells are a principal cause of failure in service due to subsequent weather exposure, mechanical flexing or diurnal temperature cycles. Existing methods have not been able to detect cracks early enough in the production cycle to prevent inadvertent shipment to customers. This program, sponsored under the DOE Photovoltaic Supply Chain and Cross-Cutting Technologies program, studied the feasibility of quantifying surface micro-discontinuities by use of a novel technique, thermoreflectance imaging, to detect surface temperature gradients with very high spatial resolution, in combination with a suite of conventional imaging methods such as electroluminescence. The project carried out laboratorymore » tests together with computational image analyses using sample solar cells with known defects supplied by industry sources or DOE National Labs. Quantitative comparisons between the effectiveness of the new technique and conventional methods were determined in terms of the smallest detectable crack. Also the robustness of the new technique for reliable microcrack detection was determined at various stages of processing such as before and after antireflectance treatments. An overall assessment is that the new technique compares favorably with existing methods such as lock-in thermography or ultrasonics. The project was 100% completed in Sept, 2010. A detailed report of key findings from this program was published as: Q.Zhou, X.Hu, K.Al-Hemyari, K.McCarthy, L.Domash and J.Hudgings, High spatial resolution characterization of silicon solar cells using thermoreflectance imaging, J. Appl. Phys, 110, 053108 (2011).« less

Consumption of a High Quantity and a Wide Variety of Vegetables Are Predicted by Different Food Choice Motives in Older Adults from France, Italy and the UK.

PubMed

Appleton, Katherine M; Dinnella, Caterina; Spinelli, Sara; Morizet, David; Saulais, Laure; Hemingway, Ann; Monteleone, Erminio; Depezay, Laurence; Perez-Cueto, Frederico J A; Hartwell, Heather

2017-08-23

Consumption of a high quantity and wide variety of vegetables is currently recommended for health. Dietary variety can be low, however, particularly for older adults. This study investigated the affective factors associated with the quantity and variety of vegetables consumed by older adults in France, Italy and the UK. Adults aged 65 years plus completed questionnaires on self-reported vegetable intake (quantity and variety), liking for vegetables, attitudes towards intake, and demographic variables. In 497 older adults (France, n = 187, Italy, n = 152, UK, n = 158), higher quantities of vegetables consumed were associated with a higher age, affluence score and liking for vegetables, and a lower importance in consumption of familiarity (smallest β = 0.11, p = 0.03). Greater variety was associated with a higher liking and importance of health benefits, and a lower importance of familiarity (smallest β = -0.11, p < 0.01). Higher quantity and variety combined (quantity × variety) was associated with a higher age, liking and importance of health benefits, and a lower importance of familiarity (smallest β = 0.14, p = 0.02). Country-specific effects were also found (smallest β = 0.20, p < 0.01). These findings demonstrate a role for liking and a lower concern for eating familiar foods in vegetable consumption, and a particular role for concern for health benefits in the consumption of a greater variety of vegetables.

Consumption of a High Quantity and a Wide Variety of Vegetables Are Predicted by Different Food Choice Motives in Older Adults from France, Italy and the UK

PubMed Central

Dinnella, Caterina; Spinelli, Sara; Morizet, David; Saulais, Laure; Hemingway, Ann; Monteleone, Erminio; Depezay, Laurence; Perez-Cueto, Federico J. A.; Hartwell, Heather

2017-01-01

Background: Consumption of a high quantity and wide variety of vegetables is currently recommended for health. Dietary variety can be low, however, particularly for older adults. This study investigated the affective factors associated with the quantity and variety of vegetables consumed by older adults in France, Italy and the UK. Methods: Adults aged 65 years plus completed questionnaires on self-reported vegetable intake (quantity and variety), liking for vegetables, attitudes towards intake, and demographic variables. Results: In 497 older adults (France, n = 187, Italy, n = 152, UK, n = 158), higher quantities of vegetables consumed were associated with a higher age, affluence score and liking for vegetables, and a lower importance in consumption of familiarity (smallest β = 0.11, p = 0.03). Greater variety was associated with a higher liking and importance of health benefits, and a lower importance of familiarity (smallest β = −0.11, p < 0.01). Higher quantity and variety combined (quantity × variety) was associated with a higher age, liking and importance of health benefits, and a lower importance of familiarity (smallest β = 0.14, p = 0.02). Country-specific effects were also found (smallest β = 0.20, p < 0.01). Conclusions: These findings demonstrate a role for liking and a lower concern for eating familiar foods in vegetable consumption, and a particular role for concern for health benefits in the consumption of a greater variety of vegetables. PMID:28832549

Estimation of distributional parameters for censored trace level water quality data: 1. Estimation techniques

USGS Publications Warehouse

Gilliom, Robert J.; Helsel, Dennis R.

1986-01-01

A recurring difficulty encountered in investigations of many metals and organic contaminants in ambient waters is that a substantial portion of water sample concentrations are below limits of detection established by analytical laboratories. Several methods were evaluated for estimating distributional parameters for such censored data sets using only uncensored observations. Their reliabilities were evaluated by a Monte Carlo experiment in which small samples were generated from a wide range of parent distributions and censored at varying levels. Eight methods were used to estimate the mean, standard deviation, median, and interquartile range. Criteria were developed, based on the distribution of uncensored observations, for determining the best performing parameter estimation method for any particular data set. The most robust method for minimizing error in censored-sample estimates of the four distributional parameters over all simulation conditions was the log-probability regression method. With this method, censored observations are assumed to follow the zero-to-censoring level portion of a lognormal distribution obtained by a least squares regression between logarithms of uncensored concentration observations and their z scores. When method performance was separately evaluated for each distributional parameter over all simulation conditions, the log-probability regression method still had the smallest errors for the mean and standard deviation, but the lognormal maximum likelihood method had the smallest errors for the median and interquartile range. When data sets were classified prior to parameter estimation into groups reflecting their probable parent distributions, the ranking of estimation methods was similar, but the accuracy of error estimates was markedly improved over those without classification.

Smallest bitter taste receptor (T2Rs) gene repertoire in carnivores.

PubMed

Hu, Ling-Ling; Shi, Peng

2013-06-01

Bitter taste reception is presumably associated with dietary selection, preventing animals from ingesting potentially harmful compounds. Accordingly, carnivores, who encounter these toxic substances less often, should have fewer genes associated with bitter taste reception compared with herbivores and omnivores. To investigate the genetic basis of bitter taste reception, we confirmed bitter taste receptor (T2R) genes previously found in the genome sequences of two herbivores (cow and horse), two omnivores (mouse and rat) and one carnivore (dog). We also identified, for the first time, the T2R repertoire from the genome of other four carnivore species (ferret, giant panda, polar bear and cat) and detected 17-20 bitter receptor genes from the five carnivore genomes, including 12-16 intact genes, 0-1 partial but putatively functional genes, and 3-8 pseudogenes. Both the intact T2R genes and the total T2R gene number among carnivores were the smallest among the tested species, supporting earlier speculations that carnivores have fewer T2R genes, herbivores an intermediate number, and omnivores the largest T2R gene repertoire. To further explain the genetic basis for this disparity, we constructed a phylogenetic tree, which showed most of the T2R genes from the five carnivores were one-to-one orthologs across the tree, suggesting that carnivore T2Rs were conserved among mammals. Similarly, the small carnivore T2R family size was likely due to rare duplication events. Collectively, these results strengthen arguments for the connection between T2R gene family size, diet and habit.

Estimation of distributional parameters for censored trace level water quality data. 1. Estimation Techniques

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

Gilliom, R.J.; Helsel, D.R.

1986-02-01

A recurring difficulty encountered in investigations of many metals and organic contaminants in ambient waters is that a substantial portion of water sample concentrations are below limits of detection established by analytical laboratories. Several methods were evaluated for estimating distributional parameters for such censored data sets using only uncensored observations. Their reliabilities were evaluated by a Monte Carlo experiment in which small samples were generated from a wide range of parent distributions and censored at varying levels. Eight methods were used to estimate the mean, standard deviation, median, and interquartile range. Criteria were developed, based on the distribution of uncensoredmore » observations, for determining the best performing parameter estimation method for any particular data det. The most robust method for minimizing error in censored-sample estimates of the four distributional parameters over all simulation conditions was the log-probability regression method. With this method, censored observations are assumed to follow the zero-to-censoring level portion of a lognormal distribution obtained by a least squares regression between logarithms of uncensored concentration observations and their z scores. When method performance was separately evaluated for each distributional parameter over all simulation conditions, the log-probability regression method still had the smallest errors for the mean and standard deviation, but the lognormal maximum likelihood method had the smallest errors for the median and interquartile range. When data sets were classified prior to parameter estimation into groups reflecting their probable parent distributions, the ranking of estimation methods was similar, but the accuracy of error estimates was markedly improved over those without classification.« less

Estimation of distributional parameters for censored trace-level water-quality data

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

Gilliom, R.J.; Helsel, D.R.

1984-01-01

A recurring difficulty encountered in investigations of many metals and organic contaminants in ambient waters is that a substantial portion of water-sample concentrations are below limits of detection established by analytical laboratories. Several methods were evaluated for estimating distributional parameters for such censored data sets using only uncensored observations. Their reliabilities were evaluated by a Monte Carlo experiment in which small samples were generated from a wide range of parent distributions and censored at varying levels. Eight methods were used to estimate the mean, standard deviation, median, and interquartile range. Criteria were developed, based on the distribution of uncensored observations,more » for determining the best-performing parameter estimation method for any particular data set. The most robust method for minimizing error in censored-sample estimates of the four distributional parameters over all simulation conditions was the log-probability regression method. With this method, censored observations are assumed to follow the zero-to-censoring level portion of a lognormal distribution obtained by a least-squares regression between logarithms of uncensored concentration observations and their z scores. When method performance was separately evaluated for each distributional parameter over all simulation conditions, the log-probability regression method still had the smallest errors for the mean and standard deviation, but the lognormal maximum likelihood method had the smallest errors for the median and interquartile range. When data sets were classified prior to parameter estimation into groups reflecting their probable parent distributions, the ranking of estimation methods was similar, but the accuracy of error estimates was markedly improved over those without classification. 6 figs., 6 tabs.« less

A flexible micromachined optical sensor for simultaneous measurement of pressure and shear force distribution on foot

NASA Astrophysics Data System (ADS)

Wang, Wei-Chih; Panergo, Reynold R.; Galvanin, Christopher M.; Ledoux, William; Sangeorzan, Bruce; Reinhall, Per G.

2003-07-01

Lower limb complications associated with diabetes include the development of plantar ulcers that can lead to infection and subsequent amputation. While it is known from force plate analyses that there are medial/lateral and anterior/posterior shear components of the ground reaction force, there is little known about the actual distribution of this force during daily activities, nor about the role that shear plays in causing plantar ulceration. Furthermore, one critical reason why these data have not been obtained previously is the lack of a validated, widely used, commercially available shear sensor, in part because of the various technical issues associated with shear measurement. Here we have developed novel means of tranducing plantar shear and pressure stress via a new microfabricated optical system. The pressure/shear sensor consists of an array of optical waveguides lying in perpendicular rows and columns separated by elastomeric pads. A map of pressure and shear stress is constructed based on observed macro bending through the intensity attenuation from the physical deformation of two adjacent perpendicular optical waveguides. The uniqueness of the sensor is in its batch fabrication process, which involves injection molding and embossing techniques with Polydimethylsiloxane (PDMS) as the optical medium. Here we present the preliminary results of the prototype. The sensor has been shown to have low noise and responds linearly to applied loads. The smallest detectable force on each sensor element based on the current setup is ~0.1 N. The smallest area we have resolved in our mesh sensor is currently 950x950μm2

LETTER TO THE EDITOR: Fractal diffusion coefficient from dynamical zeta functions

NASA Astrophysics Data System (ADS)

Cristadoro, Giampaolo

2006-03-01

Dynamical zeta functions provide a powerful method to analyse low-dimensional dynamical systems when the underlying symbolic dynamics is under control. On the other hand, even simple one-dimensional maps can show an intricate structure of the grammar rules that may lead to a non-smooth dependence of global observables on parameters changes. A paradigmatic example is the fractal diffusion coefficient arising in a simple piecewise linear one-dimensional map of the real line. Using the Baladi-Ruelle generalization of the Milnor-Thurnston kneading determinant, we provide the exact dynamical zeta function for such a map and compute the diffusion coefficient from its smallest zero.

[The principle of the energy minimum in ontogeny and the channeling of developmental processes].

PubMed

Ozerniuk, N D

1989-01-01

The principle of minimum of energy in ontogenesis has been formulated on the basis of data concerning age changes in energetic metabolism, as well as the influence of ecological factors on this process. According to this principle the smallest expenditures of energy are observed in the zone of the most favorable developmental conditions. The minimal level of energetic metabolism at every developmental stage that corresponds to the most stable state of organism is treated as homeostasis and the developmental stability is treated as homeorrhesis. Regulation mechanisms of energetic metabolism during ontogenesis and under the influence of environmental factors are analyzed.

Current state and problems of integrated development of mineral resources base in Russia

NASA Astrophysics Data System (ADS)

Filimonova, I. V.; Eder, L. V.; Mishenin, M. V.; Mamakhatov, T. M.

2017-09-01

The article deals with the issues of integrated development of subsoil resources taking into account the actual problems facing the Russian oil and gas complex. The key factors determining the need for integrated development of subsoil resources have been systematized and investigated. These factors are the change of the hydrocarbon resource base quality, the improvement of the depletion degree of basic (unique and major) oil fields, the increase in the number of small and smallest oil fields discovered and introduced into development, the increased capital intensity and the riskiness of geological exploration, and the territorial location of new subsoil use facilities.

Sign changes in sums of the Liouville function

NASA Astrophysics Data System (ADS)

Borwein, Peter; Ferguson, Ron; Mossinghoff, Michael J.

2008-09-01

The Liouville function λ(n) is the completely multiplicative function whose value is -1 at each prime. We develop some algorithms for computing the sum T(n)Dsum_{kD1}^n λ(k)/k , and use these methods to determine the smallest positive integer n where T(n)<0 . This answers a question originating in some work of Turan, who linked the behavior of T(n) to questions about the Riemann zeta function. We also study the problem of evaluating Polya's sum L(n)Dsum_{kD1}^nλ(k) , and we determine some new local extrema for this function, including some new positive values.

Optimization strategies with resource scarcity: From immunization of networks to the traveling salesman problem

NASA Astrophysics Data System (ADS)

Bellingeri, Michele; Agliari, Elena; Cassi, Davide

2015-10-01

The best strategy to immunize a complex network is usually evaluated in terms of the percolation threshold, i.e. the number of vaccine doses which make the largest connected cluster (LCC) vanish. The strategy inducing the minimum percolation threshold represents the optimal way to immunize the network. Here we show that the efficacy of the immunization strategies can change during the immunization process. This means that, if the number of doses is limited, the best strategy is not necessarily the one leading to the smallest percolation threshold. This outcome should warn about the adoption of global measures in order to evaluate the best immunization strategy.

The effect of growth temperature variation on partially bismuth filled carbon nanotubes synthesis using a soft semi-metallic template.

PubMed

Sahoo, R K; Jacob, C

2014-06-01

The dewetting of a low melting point metal thin film deposited on silicon substrates was studied. The experimental results suggest that the change in the growth temperature affects the nanostructures that form. Based on the experimental results, the temperature which yielded the smallest features for the growth of nanotubes is determined. The mechanism by which these nano-templates become an efficient seeds for the growth of the carbon nanotubes is discussed. The partial bismuth filling inside the CNTs was optimized. Based on the results, a schematic growth model for better understanding of the process parameters has also been proposed.

Contributed Review: Camera-limits for wide-field magnetic resonance imaging with a nitrogen-vacancy spin sensor

NASA Astrophysics Data System (ADS)

Wojciechowski, Adam M.; Karadas, Mürsel; Huck, Alexander; Osterkamp, Christian; Jankuhn, Steffen; Meijer, Jan; Jelezko, Fedor; Andersen, Ulrik L.

2018-03-01

Sensitive, real-time optical magnetometry with nitrogen-vacancy centers in diamond relies on accurate imaging of small (≪10-2), fractional fluorescence changes across the diamond sample. We discuss the limitations on magnetic field sensitivity resulting from the limited number of photoelectrons that a camera can record in a given time. Several types of camera sensors are analyzed, and the smallest measurable magnetic field change is estimated for each type. We show that most common sensors are of a limited use in such applications, while certain highly specific cameras allow achieving nanotesla-level sensitivity in 1 s of a combined exposure. Finally, we demonstrate the results obtained with a lock-in camera that paves the way for real-time, wide-field magnetometry at the nanotesla level and with a micrometer resolution.

Coral calcifying fluid pH dictates response to ocean acidification.

PubMed

Holcomb, M; Venn, A A; Tambutté, E; Tambutté, S; Allemand, D; Trotter, J; McCulloch, M

2014-06-06

Ocean acidification driven by rising levels of CO2 impairs calcification, threatening coral reef growth. Predicting how corals respond to CO2 requires a better understanding of how calcification is controlled. Here we show how spatial variations in the pH of the internal calcifying fluid (pHcf) in coral (Stylophora pistillata) colonies correlates with differential sensitivity of calcification to acidification. Coral apexes had the highest pHcf and experienced the smallest changes in pHcf in response to acidification. Lateral growth was associated with lower pHcf and greater changes with acidification. Calcification showed a pattern similar to pHcf, with lateral growth being more strongly affected by acidification than apical. Regulation of pHcf is therefore spatially variable within a coral and critical to determining the sensitivity of calcification to ocean acidification.

A study on the measurement of the core body temperature change after radiofrequency ablation (RFA) through MR temperature mapping

NASA Astrophysics Data System (ADS)

Kim, Chang-Bok; Dong, Kyung-Rae; Yu, Young; Chung, Woon-Kwan; Cho, Jae-Hwan; Joo, Kyu-Ji

2013-09-01

This study examined the change in the heat generated during radiofrequency ablation (RFA) using a self-manufactured phantom and used magnetic resonance imaging (MRI) to analyze the change in the temperature of the core body and the tissues surrounding the phantom. In this experiment, the image and the phase image were obtained simultaneously from a gradient echo-based sequence using 1.5-Tesla MRI equipment and a 12-channel head coil. The temperature mapping technique was used to calculate the change in temperature. The regions of interest (ROIs) (ROI 1 - ROI 6) were set with a focus on the area where the RFA was performed, according to the temperature distribution, before monitoring the temperature change for one hour in time intervals of five minutes. The results showed that the temperature change in the ROI with time was largest in the ROI 1 and smallest in the ROI 5. In addition, after the RFA procedure, the temperature decreased from the initial value to 0 °C in one hour. The temperature changes in the core body and the surrounding tissues were confirmed by MRI temperature mapping, which is a noninvasive method.

Adsorption of fibrinogen on a biomedical-grade stainless steel 316LVM surface: a PM-IRRAS study of the adsorption thermodynamics, kinetics and secondary structure changes.

PubMed

Desroches, Marie-Josee; Omanovic, Sasha

2008-05-14

Polarization-modulation infrared reflection-absorption spectroscopy (PM-IRRAS) was employed to investigate the interaction of serum protein fibrinogen with a biomedical-grade 316LVM stainless steel surface, in terms of the adsorption thermodynamics, kinetics and secondary structure changes of the protein. Apparent Gibbs energy of adsorption values indicated a highly spontaneous and strong adsorption of fibrinogen onto the surface. The kinetics of fibrinogen adsorption were successfully modeled using a pseudo first-order kinetic model. Deconvolution of the amide I bands indicated that the adsorption of fibrinogen on 316LVM results in significant changes in the protein's secondary structure that occur predominantly within the first minute of adsorption. Among the investigated structures, the alpha-helix structure undergoes the smallest changes, while the beta-sheet and beta-turns structures undergo significant changes. It was shown that lateral interactions between the adsorbed molecules do not play a role in controlling the secondary structure changes. An increase in temperature induced changes in the secondary structure of the protein, characterized by a loss of the alpha-helical content and its transformation into the beta-turns structure.

Floral meristem size and organ number correlation in Eucryphia (Cunoniaceae).

PubMed

Bull-Hereñu, Kester; Ronse de Craene, Louis; Pérez, Fernanda

2018-05-01

We present a comparative flower ontogenetic study in five species of the genus Eucryphia with the aim of testing whether differences in the organ number observed can be explained by changes in the meristematic size of floral meristem and floral organs. Species native to Oceania, viz. E. milliganii, E. lucida and E. moorei, have the smallest gynoecia with ca. 6 carpels, while the Chilean E. glutinosa and E. cordifolia present more than ten carpels. E. milliganii has the smallest flower with the lowest stamen number (ca. 50), while the other species produce around 200 stamens and more. Standardized measurements of meristematic sectors were taken in 49 developing flowers that were classified into three well-defined ontogenetic stages. Sizes of meristems varied significantly among species within each developmental stage as revealed by ANOVA analyses. Significant regressions between organ number and corresponding meristem size were consistent with the premise that a larger meristem size prior to organ initiation could be determining for a higher organ number. Flower organogenesis in Eucryphia also involves relevant meristem expansion while the organs are initiated, which results in a particular androecium patterning with a chaotic stamen arrangement. Meristem expansion also appears to be slower but more extensive in species with larger initial meristematic size, suggesting that flower phenotype can be determined in ontogeny by this heterochronic interplay of space and time.

Microwave-Assisted Synthesis of Silver Vanadium Phosphorus Oxide, Ag 2VO 2PO 4 : Crystallite Size Control and Impact on Electrochemistry

DOE PAGES

Huang, Jianping; Marschilok, Amy C.; Takeuchi, Esther S.; ...

2016-03-07

We study silver vanadium phosphorus oxide, Ag 2VO 2PO 4, that is a promising cathode material for Li batteries due in part to its large capacity and high current capability. Herein, a new synthesis of Ag 2VO 2PO 4 based on microwave heating is presented, where the reaction time is reduced by approximately 100× relative to other reported methods, and the crystallite size is controlled via synthesis temperature, showing a linear correlation of crystallite size with temperature. Notably, under galvanostatic reduction, the Ag 2VO 2PO 4 sample with the smallest crystallite size delivers the highest capacity and shows the highestmore » loaded voltage. Further, pulse discharge tests show a significant resistance decrease during the initial discharge coincident with the formation of Ag metal. Thus, the magnitude of the resistance decrease observed during pulse tests depends on the Ag 2VO 2PO 4 crystallite size, with the largest resistance decrease observed for the smallest crystallite size. Additional electrochemical measurements indicate a quasi-reversible redox reaction involving Li + insertion/deinsertion, with capacity fade due to structural changes associated with the discharge/charge process. In summary, this work demonstrates a faster synthetic approach for bimetallic polyanionic materials which also provides the opportunity for tuning of electrochemical properties through control of material physical properties such as crystallite size.« less

A novel approach to mask defect inspection

NASA Astrophysics Data System (ADS)

Sagiv, Amir; Shirman, Yuri; Mangan, Shmoolik

2008-10-01

Memory chips, now constituting a major part of semiconductor market, posit a special challenge for inspection, as they are generally produced with the smallest half-pitch available with today's technology. This is true, in particular, to photomasks of advanced memory devices, which are at the forefront of the "low-k1" regime. In this paper we present a novel photomask inspection approach, that is particularly suitable for low-k1 layers of advanced memory chips, owing to their typical dense and periodic structure. The method we present can produce a very strong signal for small mask defects, by suppression of the modulation of the pattern's image. Unlike dark-field detection, however, here a single diffraction order associated with the pattern generates a constant "gray" background image, that is used for signal enhancement. We define the theoretical basis for the new detection technique, and show, both analytically and numerically, that it can easily achieve a detection line past the printability spec, and that in cases it is at least as sensitive as high-resolution based detection. We also demonstrate this claim experimentally on a customer mask, using the platform of Applied Material's newly released Aera2TM mask inspection tool. The high sensitivity demonstrates the important and often overlooked concept that resolution is not synonymous with sensitivity. The novel detection method is advantageous in several other aspects, such as the very simple implementation, the high throughput, and the relatively simple pre- and post-processing algorithms required for signal extraction. These features, and in particular the very high sensitivity, make this novel detection method an attractive inspection option for advanced memory devices.

Got power? A systematic review of sample size adequacy in health professions education research.

PubMed

Cook, David A; Hatala, Rose

2015-03-01

Many education research studies employ small samples, which in turn lowers statistical power. We re-analyzed the results of a meta-analysis of simulation-based education to determine study power across a range of effect sizes, and the smallest effect that could be plausibly excluded. We systematically searched multiple databases through May 2011, and included all studies evaluating simulation-based education for health professionals in comparison with no intervention or another simulation intervention. Reviewers working in duplicate abstracted information to calculate standardized mean differences (SMD's). We included 897 original research studies. Among the 627 no-intervention-comparison studies the median sample size was 25. Only two studies (0.3%) had ≥80% power to detect a small difference (SMD > 0.2 standard deviations) and 136 (22%) had power to detect a large difference (SMD > 0.8). 110 no-intervention-comparison studies failed to find a statistically significant difference, but none excluded a small difference and only 47 (43%) excluded a large difference. Among 297 studies comparing alternate simulation approaches the median sample size was 30. Only one study (0.3%) had ≥80% power to detect a small difference and 79 (27%) had power to detect a large difference. Of the 128 studies that did not detect a statistically significant effect, 4 (3%) excluded a small difference and 91 (71%) excluded a large difference. In conclusion, most education research studies are powered only to detect effects of large magnitude. For most studies that do not reach statistical significance, the possibility of large and important differences still exists.

Foreign body detection in food materials using compton scattered x-rays

NASA Astrophysics Data System (ADS)

McFarlane, Nigel James Bruce

This thesis investigated the application of X-ray Compton scattering to the problem of foreign body detection in food. The methods used were analytical modelling, simulation and experiment. A criterion was defined for detectability, and a model was developed for predicting the minimum time required for detection. The model was used to predict the smallest detectable cubes of air, glass, plastic and steel. Simulations and experiments were performed on voids and glass in polystyrene phantoms, water, coffee and muesli. Backscatter was used to detect bones in chicken meat. The effects of geometry and multiple scatter on contrast, signal-to-noise, and detection time were simulated. Compton scatter was compared with transmission, and the effect of inhomogeneity was modelled. Spectral shape was investigated as a means of foreign body detection. A signal-to-noise ratio of 7.4 was required for foreign body detection in food. A 0.46 cm cube of glass or a 1.19 cm cube of polystyrene were detectable in a 10 cm cube of water in one second. The minimum time to scan a whole sample varied as the 7th power of the foreign body size, and the 5th power of the sample size. Compton scatter inspection produced higher contrasts than transmission, but required longer measurement times because of the low number of photon counts. Compton scatter inspection of whole samples was very slow compared to production line speeds in the food industry. There was potential for Compton scatter in applications which did not require whole-sample scanning, such as surface inspection. There was also potential in the inspection of inhomogeneous samples. The multiple scatter fraction varied from 25% to 55% for 2 to 10 cm cubes of water, but did not have a large effect on the detection time. The spectral shape gave good contrasts and signal-to-noise ratios in the detection of chicken bones.

Highly sensitive determination of cadmium and lead using a low-cost electrochemical flow-through cell based on a carbon paste electrode.

PubMed

Wonsawat, Wanida; Dungchai, Wijitar; Motomizu, Shoji; Chuanuwatanakul, Suchada; Chailapakul, Orawon

2012-01-01

A low-cost thin-layer electrochemical flow-through cell based on a carbon paste electrode (CPE), was constructed for the highly sensitive determination of cadmium(II) (Cd(2+)) and lead(II) (Pb(2+)) ions. The sensitivity of the proposed cell for Cd(2+) and Pb(2+) ion detection was improved by using the smallest channel height without the need for any complicated electrode modification. Under the optimum conditions, the detection limits of Cd(2+) and Pb(2+) ions (0.08 and 0.07 µg dm(-3), respectively) were 13.8- and 11.4-fold lower than that of a commercial flow cell (1.1 and 0.8 µg dm(-3), respectively). Moreover, the percentage recoveries of Cd(2+) and Pb(2+) for the in-house designed thin-layer flow cell were higher than those for the commercially available cell in all tested water samples, and within the acceptable range. The proposed flow cell is promising as an inexpensive and alternative one for the highly sensitive monitoring of heavy metal ions. 2012 © The Japan Society for Analytical Chemistry

Attomole-level protein fingerprinting based on intrinsic peptide fluorescence.

PubMed

Okerberg, E; Shear, J B

2001-04-01

Protein identification has relied heavily on proteolytic analysis, but current techniques are often slow and generally consume large quantities of valuable protein sample. We report the development of a rapid, ultralow volume protein analysis strategy based on tryptic digestion within the tip of a 1.5-microm capillary channel followed by separation of the proteolytic fragments using capillary electrophoresis (CE). Two-photon excitation is used to probe the intrinsic fluorescence of peptide fragments through "deep-UV" excitation of aromatic amino acid residues at the outlet of the CE channel. Detection limits using this technique are 0.7, 2.4, and 23 amol for the aromatic amino acids tryptophan, tyrosine, and phenylalanine, respectively. In these studies, we demonstrate the capacity to differentiate bovine and yeast cytochrome c variants using less than 15 amol of protein through tryptic fingerprinting. Moreover, the detection of a single amino acid substitution between bovine and canine cytochrome c illustrates the sensitivity of this approach to minor differences in protein sequence. The 2-pL sample volume required for this on-column tryptic digestion is, to our knowledge, the smallest yet reported for a proteolytic assay.

Fast and high resolution thermal detector based on an aluminum nitride piezoelectric microelectromechanical resonator with an integrated suspended heat absorbing element

NASA Astrophysics Data System (ADS)

Hui, Yu; Rinaldi, Matteo

2013-03-01

This letter presents a miniaturized, fast, and high resolution thermal detector, in which a heat absorbing element and a temperature sensitive microelectromechanical system (MEMS) resonator are perfectly overlapped but separated by a microscale air gap. This unique design guarantees efficient and fast (˜10s μs) heat transfer from the absorbing element to the temperature sensitive device and enables high resolution thermal power detection (˜nW), thanks to the low noise performance of the high quality factor (Q = 2305) MEMS resonant thermal detector. A device prototype was fabricated, and its detection capabilities were experimentally characterized. A thermal power as low as 150 nW was experimentally measured, and a noise equivalent power of 6.5 nW/Hz1/2 was extracted. A device thermal time constant of only 350 μs was measured (smallest ever reported for MEMS resonant thermal detectors), indicating the great potential of the proposed technology for the implementation of ultra-fast and high resolution un-cooled resonant thermal detectors.

High-performance, event-driven, low-cost, and SWaP imaging sensor for hostile fire detection, homeland protection, and border security

NASA Astrophysics Data System (ADS)

Rizk, Charbel G.; Lin, Joseph H.; Kennerly, Stephen W.; Pouliquen, Philippe; Goldberg, Arnold C.; Andreou, Andreas G.

2012-06-01

The advanced imagers team at JHU APL and ECE has been advocating and developing a new class of sensor systems that address key system level performance bottlenecks but are sufficiently flexible to allow optimization of associated cost and size, weight, and power (SWaP) for different applications and missions. A primary component of this approach is the innovative system-on-chip architecture: Flexible Readout and Integration Sensors (FRIS). This paper reports on the development and testing of a prototype based on the FRIS concept. It will include the architecture, a summary of test results to date relevant to the hostile fire detection challenge. For this application, this prototype demonstrates the potential for this concept to yield the smallest SWaP and lowest cost imaging solution with a low false alarm rate. In addition, a specific solution based on the visible band is proposed. Similar performance and SWaP gains are expected for other wavebands such as SWIR, MWIR, and LWIR and/or other applications like persistent surveillance for critical infrastructure and border control in addition to unattended sensors.

Preparation, applications, and digital simulation of carbon interdigitated array electrodes.

PubMed

Liu, Fei; Kolesov, Grigory; Parkinson, B A

2014-08-05

Carbon interdigitated array (IDA) electrodes with features sizes down to 1.2 μm were fabricated by controlled pyrolysis of patterned photoresist. Cyclic voltammetry of reversible redox species produced the expected steady-state currents. The collection efficiency depends on the IDA electrode spacing, which ranged from around 2.7 to 16.5 μm, with the smaller dimensions achieving higher collection efficiencies of up to 98%. The signal amplification because of redox cycling makes it possible to detect species at relatively low concentrations (10(-5) molar) and the small spacing allows detection of transient electrogenerated species with much shorter lifetimes (submillisecond). Digital simulation software that accounts for both the width and height of electrode elements as well as the electrode spacing was developed to model the IDA electrode response. The simulations are in quantitative agreement with experimental data for both a simple fast one electron redox reaction and an electron transfer with a following chemical reaction at the IDAs with larger gaps whereas currents measured for the smallest IDA electrodes, that were larger than the simulated currents, are attributed to convection from induced charge electrokinetic flow.

Visual acuity of the honey bee retina and the limits for feature detection.

PubMed

Rigosi, Elisa; Wiederman, Steven D; O'Carroll, David C

2017-04-06

Visual abilities of the honey bee have been studied for more than 100 years, recently revealing unexpectedly sophisticated cognitive skills rivalling those of vertebrates. However, the physiological limits of the honey bee eye have been largely unaddressed and only studied in an unnatural, dark state. Using a bright display and intracellular recordings, we here systematically investigated the angular sensitivity across the light adapted eye of honey bee foragers. Angular sensitivity is a measure of photoreceptor receptive field size and thus small values indicate higher visual acuity. Our recordings reveal a fronto-ventral acute zone in which angular sensitivity falls below 1.9°, some 30% smaller than previously reported. By measuring receptor noise and responses to moving dark objects, we also obtained direct measures of the smallest features detectable by the retina. In the frontal eye, single photoreceptors respond to objects as small as 0.6° × 0.6°, with >99% reliability. This indicates that honey bee foragers possess significantly better resolution than previously reported or estimated behaviourally, and commonly assumed in modelling of bee acuity.

Effect of knee and trunk angle on kinetic variables during the isometric midthigh pull: test-retest reliability.

PubMed

Comfort, Paul; Jones, Paul A; McMahon, John J; Newton, Robert

2015-01-01

The isometric midthigh pull (IMTP) has been used to monitor changes in force, maximum rate of force development (mRFD), and impulse, with performance in this task being associated with performance in athletic tasks. Numerous postures have been adopted in the literature, which may affect the kinetic variables during the task; therefore, the aim of this investigation was to determine whether different knee-joint angles (120°, 130°, 140°, and 150°) and hip-joint angles (125° and 145°), including the subjects preferred posture, affect force, mRFD, and impulse during the IMTP. Intraclass correlation coefficients demonstrated high within-session reliability (r ≥ .870, P < .001) for all kinetic variables determined in all postures, excluding impulse measures during the 130° knee-flexion, 125° hip-flexion posture, which showed a low to moderate reliability (r = .666-.739, P < .001), while between-sessions testing demonstrated high reliability (r > .819, P < .001) for all kinetic variables. There were no significant differences in peak force (P > .05, Cohen d = 0.037, power = .408), mRFD (P > .05, Cohen d = 0.037, power = .409), or impulse at 100 ms (P > .05, Cohen d = 0.056, power = .609), 200 ms (P > .05, Cohen d = 0.057, power = .624), or 300 ms (P > .05, Cohen d = 0.061, power = .656) across postures. Smallest detectable differences demonstrated that changes in performance of >1.3% in peak isometric force, >10.3% in mRFD, >5.3% in impulse at 100 ms, >4.4% in impulse at 200 ms, and >7.1% in impulse at 300 ms should be considered meaningful, irrespective of posture.

Cyborg mini-trainer.

PubMed

Mosso, José L; Nieto, Jesus J; Carbajal, Manuel F; Marmolejo, Jorge; Ochoa, Enrique; De La Fuente, Mireya; Almazan, Andrew; Obrador, Tomas

2009-01-01

We present the smallest surgical trainer with a total weight of 400 gr, built in aluminum of 25 cm large and 24 cm wide, and 23 cm high. It's a system integrated by a small and open module, a lamp and a microcamera connected to a Head Mounted display. It holds two endoscopic instruments, and items to make knots or sutures and enhance visual-motor coordination. The vision we got is by a small microcamera displayed to a Head Mounted Display HMD. This surgical trainer is the smallest in the worldwide, easy to install, and easy to carry.

Small-sized microplastics and pigmented particles in bottled mineral water.

PubMed

Oßmann, Barbara E; Sarau, George; Holtmannspötter, Heinrich; Pischetsrieder, Monika; Christiansen, Silke H; Dicke, Wilhelm

2018-09-15

Up to now, only a few studies about microparticle contamination of bottled mineral water have been published. The smallest analysed particle size was 5 μm. However, due to toxicological reasons, especially microparticles smaller than 1.5 μm are critically discussed. Therefore, in the present study, 32 samples of bottled mineral water were investigated for contamination by microplastics, pigment and additive particles. Due to the application of aluminium coated polycarbonate membrane filters and micro-Raman spectroscopy, a lowest analysed particle size of 1 μm was achieved. Microplastics were found in water from all bottle types: in single use and reusable bottles made of poly(ethylene terephthalate) (PET) as well as in glass bottles. The amount of microplastics in mineral water varied from 2649 ± 2857 per litre in single use PET bottles up to 6292 ± 10521 per litre in glass bottles. While in plastic bottles, the predominant polymer type was PET; in glass bottles various polymers such as polyethylene or styrene-butadiene-copolymer were found. Hence, besides the packaging itself, other contamination sources have to be considered. Pigment particles were detected in high amounts in reusable, paper labelled bottles (195047 ± 330810 pigment particles per litre in glass and 23594 ± 25518 pigment particles per litre in reusable paper labelled PET bottles). Pigment types found in water samples were the same as used for label printing, indicating the bottle cleaning process as possible contamination route. Furthermore, on average 708 ± 1024 particles per litre of the additive Tris(2,4-di-tert-butylphenyl)phosphite were found in reusable PET bottles. This additive might be leached out from the bottle material itself. Over 90% of the detected microplastics and pigment particles were smaller than 5 μm and thus not covered by previous studies. In summary, this is the first study reporting about microplastics, pigment and additive particles found in bottled mineral water samples with a smallest analysed particle size of 1 μm. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation of Satellite-Based Upper Troposphere Cloud Top Height Retrievals in Multilayer Cloud Conditions During TC4

NASA Technical Reports Server (NTRS)

Chang, Fu-Lung; Minnis, Patrick; Ayers, J. Kirk; McGill, Matthew J.; Palikonda, Rabindra; Spangenberg, Douglas A.; Smith, William L., Jr.; Yost, Christopher R.

2010-01-01

Upper troposphere cloud top heights (CTHs), restricted to cloud top pressures (CTPs) less than 500 hPa, inferred using four satellite retrieval methods applied to Twelfth Geostationary Operational Environmental Satellite (GOES-12) data are evaluated using measurements during the July August 2007 Tropical Composition, Cloud and Climate Coupling Experiment (TC4). The four methods are the single-layer CO2-absorption technique (SCO2AT), a modified CO2-absorption technique (MCO2AT) developed for improving both single-layered and multilayered cloud retrievals, a standard version of the Visible Infrared Solar-infrared Split-window Technique (old VISST), and a new version of VISST (new VISST) recently developed to improve cloud property retrievals. They are evaluated by comparing with ER-2 aircraft-based Cloud Physics Lidar (CPL) data taken during 9 days having extensive upper troposphere cirrus, anvil, and convective clouds. Compared to the 89% coverage by upper tropospheric clouds detected by the CPL, the SCO2AT, MCO2AT, old VISST, and new VISST retrieved CTPs less than 500 hPa in 76, 76, 69, and 74% of the matched pixels, respectively. Most of the differences are due to subvisible and optically thin cirrus clouds occurring near the tropopause that were detected only by the CPL. The mean upper tropospheric CTHs for the 9 days are 14.2 (+/- 2.1) km from the CPL and 10.7 (+/- 2.1), 12.1 (+/- 1.6), 9.7 (+/- 2.9), and 11.4 (+/- 2.8) km from the SCO2AT, MCO2AT, old VISST, and new VISST, respectively. Compared to the CPL, the MCO2AT CTHs had the smallest mean biases for semitransparent high clouds in both single-layered and multilayered situations whereas the new VISST CTHs had the smallest mean biases when upper clouds were opaque and optically thick. The biases for all techniques increased with increasing numbers of cloud layers. The transparency of the upper layer clouds tends to increase with the numbers of cloud layers.

Importance of sulfate radical anion formation and chemistry in heterogeneous OH oxidation of sodium methyl sulfate, the smallest organosulfate

DOE PAGES

Kwong, Kai Chung; Chim, Man Mei; Davies, James F.; ...

2018-02-27

Organosulfates are important organosulfur compounds present in atmospheric particles. While the abundance, composition, and formation mechanisms of organosulfates have been extensively investigated, it remains unclear how they transform and evolve throughout their atmospheric lifetime. To acquire a fundamental understanding of how organosulfates chemically transform in the atmosphere, this study investigates the heterogeneous OH radical-initiated oxidation of sodium methyl sulfate (CH 3SO 4Na) droplets, the smallest organosulfate detected in atmospheric particles, using an aerosol flow tube reactor at a high relative humidity (RH) of 85%. Aerosol mass spectra measured by a soft atmospheric pressure ionization source (direct analysis in real time,more » DART) coupled with a high-resolution mass spectrometer showed that neither functionalization nor fragmentation products are detected. Instead, the ion signal intensity of the bisulfate ion (HSO 4 -) has been found to increase significantly after OH oxidation. We postulate that sodium methyl sulfate tends to fragment into a formaldehyde (CH 2O) and a sulfate radical anion (SO 4 .-) upon OH oxidation. The formaldehyde is likely partitioned back to the gas phase due to its high volatility. The sulfate radical anion, similar to OH radical, can abstract a hydrogen atom from neighboring sodium methyl sulfate to form the bisulfate ion, contributing to the secondary chemistry. Kinetic measurements show that the heterogeneous OH reaction rate constant, k, is (3.79 ± 0.19) × 10 -13cm 3molecule -1s -1 with an effective OH uptake coefficient, γ eff, of 0.17 ± 0.03. While about 40% of sodium methyl sulfate is being oxidized at the maximum OH exposure (1.27 × 10 12molecule cm -3s), only a 3% decrease in particle diameter is observed. This can be attributed to a small fraction of particle mass lost via the formation and volatilization of formaldehyde. Overall, we firstly demonstrate that the heterogeneous OH oxidation of an organosulfate can lead to the formation of sulfate radical anion and produce inorganic sulfate. Fragmentation processes and sulfate radical anion chemistry play a key role in determining the compositional evolution of sodium methyl sulfate during heterogeneous OH oxidation.« less

Importance of sulfate radical anion formation and chemistry in heterogeneous OH oxidation of sodium methyl sulfate, the smallest organosulfate

NASA Astrophysics Data System (ADS)

Chung Kwong, Kai; Chim, Man Mei; Davies, James F.; Wilson, Kevin R.; Nin Chan, Man

2018-02-01

Organosulfates are important organosulfur compounds present in atmospheric particles. While the abundance, composition, and formation mechanisms of organosulfates have been extensively investigated, it remains unclear how they transform and evolve throughout their atmospheric lifetime. To acquire a fundamental understanding of how organosulfates chemically transform in the atmosphere, this work investigates the heterogeneous OH radical-initiated oxidation of sodium methyl sulfate (CH3SO4Na) droplets, the smallest organosulfate detected in atmospheric particles, using an aerosol flow tube reactor at a high relative humidity (RH) of 85 %. Aerosol mass spectra measured by a soft atmospheric pressure ionization source (direct analysis in real time, DART) coupled with a high-resolution mass spectrometer showed that neither functionalization nor fragmentation products are detected. Instead, the ion signal intensity of the bisulfate ion (HSO4-) has been found to increase significantly after OH oxidation. We postulate that sodium methyl sulfate tends to fragment into a formaldehyde (CH2O) and a sulfate radical anion (SO4 ṡ -) upon OH oxidation. The formaldehyde is likely partitioned back to the gas phase due to its high volatility. The sulfate radical anion, similar to OH radical, can abstract a hydrogen atom from neighboring sodium methyl sulfate to form the bisulfate ion, contributing to the secondary chemistry. Kinetic measurements show that the heterogeneous OH reaction rate constant, k, is (3.79 ± 0.19) × 10-13 cm3 molecule-1 s-1 with an effective OH uptake coefficient, γeff, of 0.17 ± 0.03. While about 40 % of sodium methyl sulfate is being oxidized at the maximum OH exposure (1.27 × 1012 molecule cm-3 s), only a 3 % decrease in particle diameter is observed. This can be attributed to a small fraction of particle mass lost via the formation and volatilization of formaldehyde. Overall, we firstly demonstrate that the heterogeneous OH oxidation of an organosulfate can lead to the formation of sulfate radical anion and produce inorganic sulfate. Fragmentation processes and sulfate radical anion chemistry play a key role in determining the compositional evolution of sodium methyl sulfate during heterogeneous OH oxidation.

Importance of sulfate radical anion formation and chemistry in heterogeneous OH oxidation of sodium methyl sulfate, the smallest organosulfate

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

Kwong, Kai Chung; Chim, Man Mei; Davies, James F.

Organosulfates are important organosulfur compounds present in atmospheric particles. While the abundance, composition, and formation mechanisms of organosulfates have been extensively investigated, it remains unclear how they transform and evolve throughout their atmospheric lifetime. To acquire a fundamental understanding of how organosulfates chemically transform in the atmosphere, this study investigates the heterogeneous OH radical-initiated oxidation of sodium methyl sulfate (CH 3SO 4Na) droplets, the smallest organosulfate detected in atmospheric particles, using an aerosol flow tube reactor at a high relative humidity (RH) of 85%. Aerosol mass spectra measured by a soft atmospheric pressure ionization source (direct analysis in real time,more » DART) coupled with a high-resolution mass spectrometer showed that neither functionalization nor fragmentation products are detected. Instead, the ion signal intensity of the bisulfate ion (HSO 4 -) has been found to increase significantly after OH oxidation. We postulate that sodium methyl sulfate tends to fragment into a formaldehyde (CH 2O) and a sulfate radical anion (SO 4 .-) upon OH oxidation. The formaldehyde is likely partitioned back to the gas phase due to its high volatility. The sulfate radical anion, similar to OH radical, can abstract a hydrogen atom from neighboring sodium methyl sulfate to form the bisulfate ion, contributing to the secondary chemistry. Kinetic measurements show that the heterogeneous OH reaction rate constant, k, is (3.79 ± 0.19) × 10 -13cm 3molecule -1s -1 with an effective OH uptake coefficient, γ eff, of 0.17 ± 0.03. While about 40% of sodium methyl sulfate is being oxidized at the maximum OH exposure (1.27 × 10 12molecule cm -3s), only a 3% decrease in particle diameter is observed. This can be attributed to a small fraction of particle mass lost via the formation and volatilization of formaldehyde. Overall, we firstly demonstrate that the heterogeneous OH oxidation of an organosulfate can lead to the formation of sulfate radical anion and produce inorganic sulfate. Fragmentation processes and sulfate radical anion chemistry play a key role in determining the compositional evolution of sodium methyl sulfate during heterogeneous OH oxidation.« less

Analysis of small droplets with a new detector for liquid chromatography based on laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Janzen, Christoph; Fleige, Rüdiger; Noll, Reinhard; Schwenke, Heinrich; Lahmann, Wilhelm; Knoth, Joachim; Beaven, Peter; Jantzen, Eckard; Oest, Andreas; Koke, Peter

2005-08-01

The miniaturization of analytical techniques is a general trend in speciation analytics. We have developed a new analytical technique combining high pressure liquid chromatography (HPLC) with laser-induced breakdown spectroscopy (LIBS). This enables a molecule-specific separation followed by an element-specific analysis of smallest amounts of complex samples. The liquid flow coming from a HPLC pump is transformed into a continuous stream of small droplets (diameter 50-100 μm, volume 65-500 pl) using a piezoelectric pulsed nozzle. After the detection of single droplets with a droplet detector, a Q-switched Nd:YAG Laser is triggered to emit a synchronized laser pulse that irradiates a single droplet. The droplets are evaporated and transformed to the plasma state. The spectrum emitted from the plasma is collected by a spherical mirror and directed through the entrance slit of a Paschen-Runge spectrometer equipped with channel photomultipliers. The spectrometer detects 31 elements simultaneously covering a spectral range from 120 to 589 nm. Purging the measurement chamber with argon enables the detection of vacuum-UV lines. Since the sample is transferred to the plasma state without dilution, very low flow rates in the sub-μl/min range can be realised.

Jersey number detection in sports video for athlete identification

NASA Astrophysics Data System (ADS)

Ye, Qixiang; Huang, Qingming; Jiang, Shuqiang; Liu, Yang; Gao, Wen

2005-07-01

Athlete identification is important for sport video content analysis since users often care about the video clips with their preferred athletes. In this paper, we propose a method for athlete identification by combing the segmentation, tracking and recognition procedures into a coarse-to-fine scheme for jersey number (digital characters on sport shirt) detection. Firstly, image segmentation is employed to separate the jersey number regions with its background. And size/pipe-like attributes of digital characters are used to filter out candidates. Then, a K-NN (K nearest neighbor) classifier is employed to classify a candidate into a digit in "0-9" or negative. In the recognition procedure, we use the Zernike moment features, which are invariant to rotation and scale for digital shape recognition. Synthetic training samples with different fonts are used to represent the pattern of digital characters with non-rigid deformation. Once a character candidate is detected, a SSD (smallest square distance)-based tracking procedure is started. The recognition procedure is performed every several frames in the tracking process. After tracking tens of frames, the overall recognition results are combined to determine if a candidate is a true jersey number or not by a voting procedure. Experiments on several types of sports video shows encouraging result.

Inventory of forest and rangeland and detection of forest stress

NASA Technical Reports Server (NTRS)

Heller, R. C. (Principal Investigator); Aldrich, R. C.; Weber, F. P.; Driscoll, R. S.

1973-01-01

The author has identified the following significant results. Three small scales of CIR photography were interpreted to determine the number of bark beetle-killed trees detected in each of six spot size categories. A procedure was developed to predict the probability of detecting spots in each spot size category and in turn to estimate the number of infestations and dead trees even on the smallest scale. Statistical tests of the data indicated that the linear model did not fit the data and that other models should be tested. As a result of daily monitoring of Black Hills radiometric instruments it was possible to show the spectral energy relationships in the ponderosa pine ecosystems over time. These data have been helpful for comparison with radiance signatures extracted from ERTS-1 bulk 70mm using precision microdensitometry. Effects of atmospheric interference were shown by a 30 percent increase in scene radiance on channel 4 of the satellite imagery. A calibration and scaling technique was developed and tested to enable interpretation of ERTS-1 bulk and precision data for the Atlanta test site. The technique includes calibration of a photographic copy system for the I2S image combiner and the production of scaled overlays of grid coordinate systems, study area locations, and outline maps of county boundaries.

An image-processing method to detect sub-optical features based on understanding noise in intensity measurements.

PubMed

Bhatia, Tripta

2018-07-01

Accurate quantitative analysis of image data requires that we distinguish between fluorescence intensity (true signal) and the noise inherent to its measurements to the extent possible. We image multilamellar membrane tubes and beads that grow from defects in the fluid lamellar phase of the lipid 1,2-dioleoyl-sn-glycero-3-phosphocholine dissolved in water and water-glycerol mixtures by using fluorescence confocal polarizing microscope. We quantify image noise and determine the noise statistics. Understanding the nature of image noise also helps in optimizing image processing to detect sub-optical features, which would otherwise remain hidden. We use an image-processing technique "optimum smoothening" to improve the signal-to-noise ratio of features of interest without smearing their structural details. A high SNR renders desired positional accuracy with which it is possible to resolve features of interest with width below optical resolution. Using optimum smoothening, the smallest and the largest core diameter detected is of width [Formula: see text] and [Formula: see text] nm, respectively, discussed in this paper. The image-processing and analysis techniques and the noise modeling discussed in this paper can be used for detailed morphological analysis of features down to sub-optical length scales that are obtained by any kind of fluorescence intensity imaging in the raster mode.

Ground-based detectability of terrestrial and Jovian extrasolar planets: observations of CM Draconis at Lick Observatory.

PubMed

Doyle, L R; Dunham, E T; Deeg, H J; Blue, J E; Jenkins, J M

1996-06-25

The detection of terrestrial-sized extrasolar planets from the ground has been thought to be virtually impossible due to atmospheric scintillation limits. However, we show that this is not the case especially selected (but nevertheless main sequence) stars, namely small eclipsing binaries. For the smallest of these systems, CM Draconis, several months to a few years of photometric observations with 1-m-class telescopes will be sufficient to detect the transits of any short-period planets of sizes > or = 1.5 Earth radii (RE), using cross-correlation analysis with moderately good photometry. Somewhat larger telescopes will be needed to extend this detectability to terrestrial planets in larger eclipsing binary systems. (We arbitrarily define "terrestrial planets" herein as those whose disc areas are closer to that of Earth's than Neptune's i.e., less than about 2.78 RE.) As a "spin-off" of such observations, we will also be able to detect the presence of Jovian-mass planets without transits using the timing of the eclipse minima. Eclipse minima will drift in time as the binary system is offset by a sufficiently massive planet (i.e., one Jupiter mass) about the binary/giant-planet barycenter, causing a periodic variation in the light travel time to the observer. We present here an outline of present observations taking place at the University of California Lick Observatory using the Crossley 0.9-m telescope in collaboration with other observatories (in South Korea, Crete, France, Canary Islands, and New York) to detect or constrain the existence of terrestrial planets around main sequence eclipsing binary star systems, starting with CM Draconis. We demonstrate the applicability of photometric data to the general detection of gas giant planets via eclipse minima timings in many other small-mass eclipsing binary systems as well.

Ground-based detectability of terrestrial and Jovian extrasolar planets: observations of CM Draconis at Lick Observatory

NASA Technical Reports Server (NTRS)

Doyle, L. R.; Dunham, E. T.; Deeg, H. J.; Blue, J. E.; Jenkins, J. M.

1996-01-01

The detection of terrestrial-sized extrasolar planets from the ground has been thought to be virtually impossible due to atmospheric scintillation limits. However, we show that this is not the case especially selected (but nevertheless main sequence) stars, namely small eclipsing binaries. For the smallest of these systems, CM Draconis, several months to a few years of photometric observations with 1-m-class telescopes will be sufficient to detect the transits of any short-period planets of sizes > or = 1.5 Earth radii (RE), using cross-correlation analysis with moderately good photometry. Somewhat larger telescopes will be needed to extend this detectability to terrestrial planets in larger eclipsing binary systems. (We arbitrarily define "terrestrial planets" herein as those whose disc areas are closer to that of Earth's than Neptune's i.e., less than about 2.78 RE.) As a "spin-off" of such observations, we will also be able to detect the presence of Jovian-mass planets without transits using the timing of the eclipse minima. Eclipse minima will drift in time as the binary system is offset by a sufficiently massive planet (i.e., one Jupiter mass) about the binary/giant-planet barycenter, causing a periodic variation in the light travel time to the observer. We present here an outline of present observations taking place at the University of California Lick Observatory using the Crossley 0.9-m telescope in collaboration with other observatories (in South Korea, Crete, France, Canary Islands, and New York) to detect or constrain the existence of terrestrial planets around main sequence eclipsing binary star systems, starting with CM Draconis. We demonstrate the applicability of photometric data to the general detection of gas giant planets via eclipse minima timings in many other small-mass eclipsing binary systems as well.

Variation in Ambient and 77K Leaf-Level Chlorophyll Fluorescence Spectra of Boreal Species During Spring Recovery of Photosynthesis. Comparison of Methods.

NASA Astrophysics Data System (ADS)

Rajewicz, P. A.; Atherton, J.; Porcar-Castell, A.

2017-12-01

Chlorophyll fluorescence (ChF) is widely used as a tool for tracking changes in photosynthetic activity. In contrast to traditional active methods, which can be applied to leaf-level studies, new passive fluorescence methods are applied to study the photosynthetic dynamics of whole plants, canopies and ecosystems. A number of open questions still remain as to how the shape and intensity of the fluorescence spectra is connected to the mechanistic acclimation of photosynthesis. This is particularly critical at the leaf-level, which is the smallest scale at which spectral fluorescence can be measured in vivo, and especially for conifer needles which are difficult to measure due to their complex geometry.The goal of our research was to develop a protocol for measuring ambient and 77K spectral fluorescence in intact leaves and to use it for tracking the seasonal dynamics in leaf fluorescence properties across boreal species and different canopy heights, including: two conifers, Pinus silvestris and Picea abies; one broadleaf tree, Betula Pendula; and two ground species: Vaccinium vitis-idaea and Vaccinium myrtillus. This activity was organized as part of the multiscale FAST campaign "Fluorescence Across Space and Time" (February 9th - July 11th 2017, Hyytiälä Forest Station, SMEAR II, Finland).We assessed the impact of using "needle-mats" as a reliable method to track seasonal changes in spectral fluorescence properties of needles. In addition, we developed a spectral box to facilitate the measurement of ambient and 77K temperature fluorescence spectra from exactly the same leaf sample footprint. The resulting data can be used to study the impact of photosystem reorganization on the in vivo spectra. Here we present our findings in regard to the comparison of ambient and 77K fluorescence spectra, which can improve the current understanding of structural photosystems' changes detectable through fluorescence signal.

The inner CSF–brain barrier: developmentally controlled access to the brain via intercellular junctions

PubMed Central

Whish, Sophie; Dziegielewska, Katarzyna M.; Møllgård, Kjeld; Noor, Natassya M.; Liddelow, Shane A.; Habgood, Mark D.; Richardson, Samantha J.; Saunders, Norman R.

2015-01-01

In the adult the interface between the cerebrospinal fluid and the brain is lined by the ependymal cells, which are joined by gap junctions. These intercellular connections do not provide a diffusional restrain between the two compartments. However, during development this interface, initially consisting of neuroepithelial cells and later radial glial cells, is characterized by “strap” junctions, which limit the exchange of different sized molecules between cerebrospinal fluid and the brain parenchyma. Here we provide a systematic study of permeability properties of this inner cerebrospinal fluid-brain barrier during mouse development from embryonic day, E17 until adult. Results show that at fetal stages exchange across this barrier is restricted to the smallest molecules (286Da) and the diffusional restraint is progressively removed as the brain develops. By postnatal day P20, molecules the size of plasma proteins (70 kDa) diffuse freely. Transcriptomic analysis of junctional proteins present in the cerebrospinal fluid-brain interface showed expression of adherens junctional proteins, actins, cadherins and catenins changing in a development manner consistent with the observed changes in the permeability studies. Gap junction proteins were only identified in the adult as was claudin-11. Immunohistochemistry was used to localize at the cellular level some of the adherens junctional proteins of genes identified from transcriptomic analysis. N-cadherin, β - and α-catenin immunoreactivity was detected outlining the inner CSF-brain interface from E16; most of these markers were not present in the adult ependyma. Claudin-5 was present in the apical-most part of radial glial cells and in endothelial cells in embryos, but only in endothelial cells including plexus endothelial cells in adults. Claudin-11 was only immunopositive in the adult, consistent with results obtained from transcriptomic analysis. These results provide information about physiological, molecular and morphological-related permeability changes occurring at the inner cerebrospinal fluid-brain barrier during brain development. PMID:25729345

Temporal variation of autotrophic picoplankton contribution to coastal phytoplankton communities over a seasonal cycle: A case study

NASA Astrophysics Data System (ADS)

Koçum, Esra

2017-04-01

Autotrophic pico-plankton form the smallest component of phytoplankton and refers to cells smaller than 2 µM. It is phylogenetically diverse and have both prokaryotic and eukaryotic components. Prokaryotic pico-autotrophs are unicellular cyanobacteria, represented mainly by Prochlorococcus and Synechococcus genera. Pico-eukaryotes are more diverse and include members of Chlorophyta, Cryptophyta, Haptophyta and Heterokontophyta. Owing to their higher nutrient acquisition capacity, relative share of pico-plankton in autotrophic production and biomass can be significant and even dominant in oligotrophic regions such as in warm tropical waters. They also fare better than larger members of phytoplankton communities under light limitation and under increasing temperature. Recent work has shown that autotrophic pico-plankton can be a significant component of coastal phytoplankton. In view of the global warming related increase in the sea surface temperature and nutrient enrichment of coastal waters, it is necessary to understand variation in the relative share of different sized groups in phytoplankton communities of coastal ecosystems including pico-plankton biomass as it shows the potential for development of microbial food web. Here, an interpretation of temporal patterns detected in the biomass and the relative contribution of pico-sized (< 2 µm) members of phytoplankton was made using data collected from two coastal sites over a year. The findings revealed the significant spatio-temporal variation in both actual pico-plankton biomass and its relative share in phytoplankton. The average biomass values of pico-plankton were 0.23 ± 0.02 µ g chl a L-1 and 0.15 ± 0.01 µg chl a L-1 at nutrient-poor and nutrient-rich sites; respectively. The temporal pattern of change displayed by picoplankton biomass was not seasonal at nutrient rich site while at nutrient poor site it was seasonal with low values measured over winter suggesting it was the seasonal changes leading to the emergence of temporal pattern of change in pico-plankton abundance observed at this site.

Psychometric properties of self-reported questionnaires for the evaluation of symptoms and functional limitations in individuals with rotator cuff disorders: a systematic review.

PubMed

St-Pierre, Corinne; Desmeules, François; Dionne, Clermont E; Frémont, Pierre; MacDermid, Joy C; Roy, Jean-Sébastien

2016-01-01

To conduct a systematic review of the psychometric properties (reliability, validity and responsiveness) of self-report questionnaires used to assess symptoms and functional limitations of individuals with rotator cuff (RC) disorders. A systematic search in three databases (Cinahl, Medline and Embase) was conducted. Data extraction and critical methodological appraisal were performed independently by three raters using structured tools, and agreement was achieved by consensus. A descriptive synthesis was performed. One-hundred and twenty articles reporting on 11 questionnaires were included. All questionnaires were highly reliable and responsive to change, and showed construct validity; seven questionnaires also shown known-group validity. The minimal detectable change ranged from 6.4% to 20.8% of total score; only two questionnaires (American Shoulder and Elbow Surgeon questionnaire [ASES] and Upper Limb Functional Index [ULFI]) had a measurement error below 10% of global score. Minimal clinically important differences were established for eight questionnaires, and ranged from 8% to 20% of total score. Overall, included questionnaires showed acceptable psychometric properties for individuals with RC disorders. The ASES and ULFI have the smallest absolute error of measurement, while the Western Ontario RC Index is one of the most responsive questionnaires for individuals suffering from RC disorders. All included questionnaires are reliable, valid and responsive for the evaluation of individuals with RC disorders. As all included questionnaires showed good psychometric properties for the targeted population, the choice should be made according to the purpose of the evaluation and to the construct being evaluated by the questionnaire. The WORC, a RC-specific questionnaire, appeared to be more responsive. It should therefore be used to evaluate change in time. If the evaluation is time-limited, shorter questionnaires or short versions should be considered (such as Quick DASH or SST).

Some Observations on Damage Tolerance Analyses in Pressure Vessels

NASA Technical Reports Server (NTRS)

Raju, Ivatury S.; Dawicke, David S.; Hampton, Roy W.

2017-01-01

AIAA standards S080 and S081 are applicable for certification of metallic pressure vessels (PV) and composite overwrap pressure vessels (COPV), respectively. These standards require damage tolerance analyses with a minimum reliable detectible flaw/crack and demonstration of safe life four times the service life with these cracks at the worst-case location in the PVs and oriented perpendicular to the maximum principal tensile stress. The standards require consideration of semi-elliptical surface cracks in the range of aspect ratios (crack depth a to half of the surface length c, i.e., (a/c) of 0.2 to 1). NASA-STD-5009 provides the minimum reliably detectible standard crack sizes (90/95 probability of detection (POD) for several non-destructive evaluation (NDE) methods (eddy current (ET), penetrant (PT), radiography (RT) and ultrasonic (UT)) for the two limits of the aspect ratio range required by the AIAA standards. This paper tries to answer the questions: can the safe life analysis consider only the life for the crack sizes at the two required limits, or endpoints, of the (a/c) range for the NDE method used or does the analysis need to consider values within that range? What would be an appropriate method to interpolate 90/95 POD crack sizes at intermediate (a/c) values? Several procedures to develop combinations of a and c within the specified range are explored. A simple linear relationship between a and c is chosen to compare the effects of seven different approaches to determine combinations of aj and cj that are between the (a/c) endpoints. Two of the seven are selected for evaluation: Approach I, the simple linear relationship, and a more conservative option, Approach III. For each of these two Approaches, the lives are computed for initial semi-elliptic crack configurations in a plate subjected to remote tensile fatigue loading with an R-ratio of 0.1, for an assumed material evaluated using NASGRO (registered 4) version 8.1. These calculations demonstrate that for this loading, using Approach I and the initial detectable crack sizes at the (a/c) endpoints in 5009 specified for the ET and UT NDE methods, the smallest life is not at the two required limits of the (a/c) range, but rather is at an intermediate configuration in the range (a/c) of 0.4 to 0.6. Similar analyses using both Approach I and III with the initial detectable crack size at the (a/c) endpoints in 5009 for PT NDE showed the smallest life may be at an (a/c) endpoint or an intermediate (a/c), depending upon which Approach is used. As such, analyses that interrogate only the two (a/c) values of 0.2 and 1 may result in unconservative life predictions. The standard practice may need to be revised based on these results.

Allelopathic and Bloom-Forming Picocyanobacteria in a Changing World

PubMed Central

Maculewicz, Jakub; Barreiro Felpeto, Aldo; Latała, Adam

2018-01-01

Picocyanobacteria are extremely important organisms in the world’s oceans and freshwater ecosystems. They play an essential role in primary production and their domination in phytoplankton biomass is common in both oligotrophic and eutrophic waters. Their role is expected to become even more relevant with the effect of climate change. However, this group of photoautotrophic organisms still remains insufficiently recognized. Only a few works have focused in detail on the occurrence of massive blooms of picocyanobacteria, their toxicity and allelopathic activity. Filling the gap in our knowledge about the mechanisms involved in the proliferation of these organisms could provide a better understanding of aquatic environments. In this review, we gathered and described recent information about allelopathic activity of picocyanobacteria and occurrence of their massive blooms in many aquatic ecosystems. We also examined the relationships between climate change and representative picocyanobacterial genera from freshwater, brackish and marine ecosystems. This work emphasizes the importance of studying the smallest picoplanktonic fractions of cyanobacteria. PMID:29361682

Selection of high temperature thermal energy storage materials for advanced solar dynamic space power systems

NASA Technical Reports Server (NTRS)

Lacy, Dovie E.; Coles-Hamilton, Carolyn; Juhasz, Albert

1987-01-01

Under the direction of NASA's Office of Aeronautics and Technology (OAST), the NASA Lewis Research Center has initiated an in-house thermal energy storage program to identify combinations of phase change thermal energy storage media for use with a Brayton and Stirling Advanced Solar Dynamic (ASD) space power system operating between 1070 and 1400 K. A study has been initiated to determine suitable combinations of thermal energy storage (TES) phase change materials (PCM) that result in the smallest and lightest weight ASD power system possible. To date the heats of fusion of several fluoride salt mixtures with melting points greater than 1025 K have been verified experimentally. The study has indicated that these salt systems produce large ASD systems because of their inherent low thermal conductivity and low density. It is desirable to have PCMs with high densities and high thermal conductivities. Therefore, alternate phase change materials based on metallic alloy systems are also being considered as possible TES candidates for future ASD space power systems.

Multicomponent diffusion in basaltic melts at 1350 °C

NASA Astrophysics Data System (ADS)

Guo, Chenghuan; Zhang, Youxue

2018-05-01

Nine successful diffusion couple experiments were conducted in an 8-component SiO2-TiO2-Al2O3-FeO-MgO-CaO-Na2O-K2O system at ∼1350 °C and at 1 GPa, to study multicomponent diffusion in basaltic melts. At least 3 traverses were measured to obtain diffusion profiles for each experiment. Multicomponent diffusion matrix at 1350 °C was obtained by simultaneously fitting diffusion profiles of diffusion couple experiments. Furthermore, in order to better constrain the diffusion matrix and reconcile mineral dissolution data, mineral dissolution experiments in the literature and diffusion couple experiments from this study, were fit together. All features of diffusion profiles in both diffusion couple and mineral dissolution experiments were well reproduced by the diffusion matrix. Diffusion mechanism is inferred from eigenvectors of the diffusion matrix, and it shows that the diffusive exchange between network-formers SiO2 and Al2O3 is the slowest, the exchange of SiO2 with other oxide components is the second slowest with an eigenvalue that is only ∼10% larger, then the exchange between divalent oxide components and all the other oxide components is the third slowest with an eigenvalue that is twice the smallest eigenvalue, then the exchange of FeO + K2O with all the other oxide components is the fourth slowest with an eigenvalue that is 5 times the smallest eigenvalue, then the exchange of MgO with FeO + CaO is the third fastest with an eigenvalue that is 6.3 times the smallest eigenvalue, then the exchange of CaO + K2O with all the other oxide components is the second fastest with an eigenvalue that is 7.5 times the smallest eigenvalue, and the exchange of Na2O with all other oxide components is the fastest with an eigenvalue that is 31 times the smallest eigenvalue. The slowest and fastest eigenvectors are consistent with those for simpler systems in most literature. The obtained diffusion matrix was successfully applied to predict diffusion profiles during mineral dissolution in basaltic melts.

Dramatic Change in Jupiter's Great Red Spot from Spacecraft Observations

NASA Technical Reports Server (NTRS)

Simon, Amy A.; Wong, Michael H.; Rogers, John H.; Orton, Glenn S.; de Pater, Imke; Asay-Davis, Xylar; Carlson, Robert W.; Marcus, Philip S.

2015-01-01

Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features. Since the advent of modern telescopes, keen observers have noted its appearance and documented a change in shape from very oblong to oval, confirmed in measurements from spacecraft data. It currently spans the smallest latitude and longitude size ever recorded. Here we show that this change has been accompanied by an increase in cloud/haze reflectance as sensed in methane gas absorption bands, increased absorption at wavelengths shorter than 500 nanometers, and increased spectral slope between 500 and 630 nanometers. These changes occurred between 2012 and 2014, without a significant change in internal tangential wind speeds; the decreased size results in a 3.2 day horizontal cloud circulation period, shorter than previously observed. As the GRS has narrowed in latitude, it interacts less with the jets flanking its north and south edges, perhaps allowing for less cloud mixing and longer UV irradiation of cloud and aerosol particles. Given its long life and observational record, we expect that future modeling of the GRS's changes, in concert with laboratory flow experiments, will drive our understanding of vortex evolution and stability in a confined flow field crucial for comparison with other planetary atmospheres.

Analysis of Intergrade Variables In The Fuzzy C-Means And Improved Algorithm Cat Swarm Optimization(FCM-ISO) In Search Segmentation

NASA Astrophysics Data System (ADS)

Saragih, Jepronel; Salim Sitompul, Opim; Situmorang, Zakaria

2017-12-01

One of the techniques known in Data Mining namely clustering. Image segmentation process does not always represent the actual image which is caused by a combination of algorithms as long as it has not been able to obtain optimal cluster centers. In this research will search for the smallest error with the counting result of a Fuzzy C Means process optimized with Cat swam Algorithm Optimization that has been developed by adding the weight of the energy in the process of Tracing Mode.So with the parameter can be determined the most optimal cluster centers and most closely with the data will be made the cluster. Weigh inertia in this research, namely: (0.1), (0.2), (0.3), (0.4), (0.5), (0.6), (0.7), (0.8) and (0.9). Then compare the results of each variable values inersia (W) which is different and taken the smallest results. Of this weighting analysis process can acquire the right produce inertia variable cost function the smallest.

Sensitivity analysis of a ground-water-flow model

USGS Publications Warehouse

Torak, Lynn J.; ,

1991-01-01

A sensitivity analysis was performed on 18 hydrological factors affecting steady-state groundwater flow in the Upper Floridan aquifer near Albany, southwestern Georgia. Computations were based on a calibrated, two-dimensional, finite-element digital model of the stream-aquifer system and the corresponding data inputs. Flow-system sensitivity was analyzed by computing water-level residuals obtained from simulations involving individual changes to each hydrological factor. Hydrological factors to which computed water levels were most sensitive were those that produced the largest change in the sum-of-squares of residuals for the smallest change in factor value. Plots of the sum-of-squares of residuals against multiplier or additive values that effect change in the hydrological factors are used to evaluate the influence of each factor on the simulated flow system. The shapes of these 'sensitivity curves' indicate the importance of each hydrological factor to the flow system. Because the sensitivity analysis can be performed during the preliminary phase of a water-resource investigation, it can be used to identify the types of hydrological data required to accurately characterize the flow system prior to collecting additional data or making management decisions.

Gravitational-Wave Constraints on the Neutron-Star-Matter Equation of State

NASA Astrophysics Data System (ADS)

Annala, Eemeli; Gorda, Tyler; Kurkela, Aleksi; Vuorinen, Aleksi

2018-04-01

The detection of gravitational waves originating from a neutron-star merger, GW170817, by the LIGO and Virgo Collaborations has recently provided new stringent limits on the tidal deformabilities of the stars involved in the collision. Combining this measurement with the existence of two-solar-mass stars, we generate a generic family of neutron-star-matter equations of state (EOSs) that interpolate between state-of-the-art theoretical results at low and high baryon density. Comparing the results to ones obtained without the tidal-deformability constraint, we witness a dramatic reduction in the family of allowed EOSs. Based on our analysis, we conclude that the maximal radius of a 1.4-solar-mass neutron star is 13.6 km, and that the smallest allowed tidal deformability of a similar-mass star is Λ (1.4 M⊙)=120 .

Electrophoretic studies of polygalacturonate oligomers and their interactions with metal ions.

PubMed

Wiedmer, S K; Cassely, A; Hong, M; Novotny, M V; Riekkola, M L

2000-09-01

Polygalacturonic acid, a linear homopolysaccharide, was investigated by capillary electrophoresis (CE) using linear polyacrylamide-coated capillaries and laser-induced fluorescence (LIF) detection. A successful separation of its fluorescently labeled oligomers was achieved through sieving in polyacrylamide entangled matrices. The reaction conditions for the derivatization of polygalacturonic acid were optimized. In studying the interactions between polygalacturonic acid and various metal ions, the end-label, free-solution electrophoretic (ELFSE) technique, developed earlier in our laboratory (Sudor, J., Novotny, M. V., Anal. Chem. 1995, 67, 4205-4209) was found preferable to the sieving method. ELFSE is fast and convenient in that no polymer solutions are needed for the separation. The investigation showed that for the moderately large oligomers, the strongest binding occurred with calcium and cadmium ions, while the smallest interaction was observed with magnesium ions.

X-ray microanalysis in the scanning electron microscope.

PubMed

Roomans, Godfried M; Dragomir, Anca

2014-01-01

X-ray microanalysis conducted using the scanning electron microscope is a technique that allows the determination of chemical elements in bulk or semi-thick specimens. The lowest concentration of an element that can be detected is in the order of a few mmol/kg or a few hundred parts per million, and the smallest amount is in the order of 10(-18) g. The spatial resolution of the analysis depends on the thickness of the specimen. For biological specimen analysis, care must be taken to prevent displacement/loss of the element of interest (usually ions). Protocols are presented for the processing of frozen-hydrated and freeze-dried specimens, as well as for the analysis of small volumes of fluid, cell cultures, and other specimens. Aspects of qualitative and quantitative analysis are covered, including limitations of the technique.

X-ray microanalysis in the scanning electron microscope.

PubMed

Roomans, Godfried M; Dragomir, Anca

2007-01-01

X-ray microanalysis conducted using the scanning electron microscope is a technique that allows the determination of chemical elements in bulk or semithick specimens. The lowest concentration of an element that can be detected is in the order of a few mmol/kg or a few hundred parts per million, and the smallest amount is in the order of 10(-18) g. The spatial resolution of the analysis depends on the thickness of the specimen. For biological specimen analysis, care must be taken to prevent displacement/loss of the element of interest (usually ions). Protocols are presented for the processing of frozen-hydrated and freeze-dried specimens, as well as for the analysis of small volumes of fluid, cell cultures and other specimens. Aspects of qualitative and quantitative analysis are covered, including limitations of the technique.

Correlation Between Optoelectronic and Positron Lifetime Properties in As-received and Plasma-treated ZnO Nanopowders

NASA Astrophysics Data System (ADS)

Peters, R. M.; Paramo, J. A.; Quarles, C. A.; Strzhemechny, Y. M.

2009-03-01

We employed photoluminescence and positron lifetime measurements on a number of commercially available ZnO nanopowders. The experiments were performed before and after processing of these samples in remote N and O/He plasma. In all the nanopowders, the average lifetime component is substantially longer than in a single-crystalline sample, consistent with the model of grains with defect-rich surface and subsurface layers. However, the sample-to-sample differences in the quality of the powders, as detected by the photoluminescence spectroscopy, obscure observation of possible size effects. Compression of the powders into pellets yields reductions of the average positron lifetimes. Plasma-induced modifications are most visible in the low-temperature photoluminescence spectra of the smallest nanocrystals, indicative of a surface-specific nature of the chosen treatment procedure.

Performance of Distributed CFAR Processors in Pearson Distributed Clutter

NASA Astrophysics Data System (ADS)

Messali, Zoubeida; Soltani, Faouzi

2006-12-01

This paper deals with the distributed constant false alarm rate (CFAR) radar detection of targets embedded in heavy-tailed Pearson distributed clutter. In particular, we extend the results obtained for the cell averaging (CA), order statistics (OS), and censored mean level CMLD CFAR processors operating in positive alpha-stable (P&S) random variables to more general situations, specifically to the presence of interfering targets and distributed CFAR detectors. The receiver operating characteristics of the greatest of (GO) and the smallest of (SO) CFAR processors are also determined. The performance characteristics of distributed systems are presented and compared in both homogeneous and in presence of interfering targets. We demonstrate, via simulation results, that the distributed systems when the clutter is modelled as positive alpha-stable distribution offer robustness properties against multiple target situations especially when using the "OR" fusion rule.

Discovery of skin alkaloids in a miniaturized eleutherodactylid frog from Cuba

PubMed Central

Rodríguez, Ariel; Poth, Dennis; Schulz, Stefan; Vences, Miguel

2011-01-01

Four phylogenetically independent lineages of frogs are currently known to sequester lipid-soluble skin alkaloids for which a dietary source has been demonstrated. We report here a remarkable fifth such instance, in Eleutherodactylus iberia and Eleutherodactylus orientalis, two species of miniaturized frogs of the family Eleutherodactylidae from Cuba. Six pumiliotoxins and two indolizidines were found in E. iberia, one of the smallest frogs in the world and characterized by a contrasting colour pattern for which we hypothesize an aposematic function. Analyses of stomach content indicated a numerical prevalence of mites with an important proportion of oribatids—a group of arthropods known to contain one of the pumiliotoxins detected in E. iberia. This suggests that miniaturization and specialization to small prey may have favoured the acquisition of dietary skin alkaloids in these amphibians. PMID:21047848

Empirical Evaluation of Hunk Metrics as Bug Predictors

NASA Astrophysics Data System (ADS)

Ferzund, Javed; Ahsan, Syed Nadeem; Wotawa, Franz

Reducing the number of bugs is a crucial issue during software development and maintenance. Software process and product metrics are good indicators of software complexity. These metrics have been used to build bug predictor models to help developers maintain the quality of software. In this paper we empirically evaluate the use of hunk metrics as predictor of bugs. We present a technique for bug prediction that works at smallest units of code change called hunks. We build bug prediction models using random forests, which is an efficient machine learning classifier. Hunk metrics are used to train the classifier and each hunk metric is evaluated for its bug prediction capabilities. Our classifier can classify individual hunks as buggy or bug-free with 86 % accuracy, 83 % buggy hunk precision and 77% buggy hunk recall. We find that history based and change level hunk metrics are better predictors of bugs than code level hunk metrics.

Photographer : JPL Europa , the smallest of the Galilean satellites, or Moons , of Jupiter , is seen

NASA Technical Reports Server (NTRS)

1979-01-01

Photographer : JPL Europa , the smallest of the Galilean satellites, or Moons , of Jupiter , is seen here as taken by Voyager 1. Range : 2 million km (1.2 million miles) is centered at about the 300 degree Meridian. The bright areas are probably ice deposits, while the dark may be rocky surface or areas of more patchy ice distribution. Most unusual features are systems of linear structures crossing the surface in various directions. Of these, some of which are over 1000 km. long , & 2 or 3 hundred km. wide, may be faults which have disrupted the surface.

A new primary mobility tool for the visually impaired: A white cane-adaptive mobility device hybrid.

PubMed

Rizzo, John-Ross; Conti, Kyle; Thomas, Teena; Hudson, Todd E; Wall Emerson, Robert; Kim, Dae Shik

2017-05-16

This article describes pilot testing of an adaptive mobility device-hybrid (AMD-H) combining properties of two primary mobility tools for people who are blind: the long cane and adaptive mobility devices (AMDs). The long cane is the primary mobility tool used by people who are blind and visually impaired for independent and safe mobility and AMDs are adaptive devices that are often lightweight frames approximately body width in lateral dimension that are simply pushed forward to clear the space in front of a person. The prototype cane built for this study had a wing apparatus that could be folded around the shaft of a cane but when unfolded, deployed two wheeled wings 25 cm (9.8 in) to each side of the canetip. This project explored drop-off and obstacle detection for 6 adults with visual impairment using the deployed AMD-H and a standard long cane. The AMD-H improved obstacle detection overall, and was most effective for the smallest obstacles (2 and 6 inch diameter). The AMD-H cut the average drop off threshold from 1.79 inches (4.55 cm) to .96 inches (2.44 cm). All participants showed a decrease in drop off detection threshold and an increase in detection rate (13.9% overall). For drop offs of 1 in (2.54 cm) and 3 in (7.62 cm), all participants showed large improvements with the AMD-H, ranging from 8.4 to 50%. The larger drop offs of 5 in (12.7 cm) and 7 in (17.8 cm) were well detected by both types of canes.

Global View of the Arctic Ocean

NASA Image and Video Library

2000-09-20

NASA researchers have new [sic] insights into the mysteries of Arctic sea ice, thanks to the unique abilities of Canada's Radarsat satellite. The Arctic is the smallest of the world's four oceans, but it may play a large role in helping scientists monitor Earth's climate shifts. Using Radarsat's special sensors to take images at night and to peer through clouds, NASA researchers can now see the complete ice cover of the Arctic. This allows tracking of any shifts and changes, in unprecedented detail, over the course of an entire winter. The radar-generated, high-resolution images are up to 100 times better than those taken by previous satellites. http://photojournal.jpl.nasa.gov/catalog/PIA02970

System identification of analytical models of damped structures

NASA Technical Reports Server (NTRS)

Fuh, J.-S.; Chen, S.-Y.; Berman, A.

1984-01-01

A procedure is presented for identifying linear nonproportionally damped system. The system damping is assumed to be representable by a real symmetric matrix. Analytical mass, stiffness and damping matrices which constitute an approximate representation of the system are assumed to be available. Given also are an incomplete set of measured natural frequencies, damping ratios and complex mode shapes of the structure, normally obtained from test data. A method is developed to find the smallest changes in the analytical model so that the improved model can exactly predict the measured modal parameters. The present method uses the orthogonality relationship to improve mass and damping matrices and the dynamic equation to find the improved stiffness matrix.

Exciton polarization, fine-structure splitting, and the asymmetry of quantum dots under uniaxial stress.

PubMed

Gong, Ming; Zhang, Weiwei; Guo, Guang-Can; He, Lixin

2011-06-03

We derive a general relation between the fine-structure splitting (FSS) and the exciton polarization angle of self-assembled quantum dots under uniaxial stress. We show that the FSS lower bound under external stress can be predicted by the exciton polarization angle and FSS under zero stress. The critical stress can also be determined by monitoring the change in exciton polarization angle. We confirm the theory by performing atomistic pseudopotential calculations for the InAs/GaAs quantum dots. The work provides deep insight into the dot asymmetry and their optical properties and a useful guide in selecting quantum dots with the smallest FSS, which are crucial in entangled photon source applications.

Biomarker clusters are differentially associated with longitudinal cognitive decline in late midlife

PubMed Central

Racine, Annie M.; Koscik, Rebecca L.; Berman, Sara E.; Nicholas, Christopher R.; Clark, Lindsay R.; Okonkwo, Ozioma C.; Rowley, Howard A.; Asthana, Sanjay; Bendlin, Barbara B.; Blennow, Kaj; Zetterberg, Henrik; Gleason, Carey E.; Carlsson, Cynthia M.

2016-01-01

The ability to detect preclinical Alzheimer’s disease is of great importance, as this stage of the Alzheimer’s continuum is believed to provide a key window for intervention and prevention. As Alzheimer’s disease is characterized by multiple pathological changes, a biomarker panel reflecting co-occurring pathology will likely be most useful for early detection. Towards this end, 175 late middle-aged participants (mean age 55.9 ± 5.7 years at first cognitive assessment, 70% female) were recruited from two longitudinally followed cohorts to undergo magnetic resonance imaging and lumbar puncture. Cluster analysis was used to group individuals based on biomarkers of amyloid pathology (cerebrospinal fluid amyloid-β42/amyloid-β40 assay levels), magnetic resonance imaging-derived measures of neurodegeneration/atrophy (cerebrospinal fluid-to-brain volume ratio, and hippocampal volume), neurofibrillary tangles (cerebrospinal fluid phosphorylated tau181 assay levels), and a brain-based marker of vascular risk (total white matter hyperintensity lesion volume). Four biomarker clusters emerged consistent with preclinical features of (i) Alzheimer’s disease; (ii) mixed Alzheimer’s disease and vascular aetiology; (iii) suspected non-Alzheimer’s disease aetiology; and (iv) healthy ageing. Cognitive decline was then analysed between clusters using longitudinal assessments of episodic memory, semantic memory, executive function, and global cognitive function with linear mixed effects modelling. Cluster 1 exhibited a higher intercept and greater rates of decline on tests of episodic memory. Cluster 2 had a lower intercept on a test of semantic memory and both Cluster 2 and Cluster 3 had steeper rates of decline on a test of global cognition. Additional analyses on Cluster 3, which had the smallest hippocampal volume, suggest that its biomarker profile is more likely due to hippocampal vulnerability and not to detectable specific volume loss exceeding the rate of normal ageing. Our results demonstrate that pathology, as indicated by biomarkers, in a preclinical timeframe is related to patterns of longitudinal cognitive decline. Such biomarker patterns may be useful for identifying at-risk populations to recruit for clinical trials. PMID:27324877

Biomarker clusters are differentially associated with longitudinal cognitive decline in late midlife.

PubMed

Racine, Annie M; Koscik, Rebecca L; Berman, Sara E; Nicholas, Christopher R; Clark, Lindsay R; Okonkwo, Ozioma C; Rowley, Howard A; Asthana, Sanjay; Bendlin, Barbara B; Blennow, Kaj; Zetterberg, Henrik; Gleason, Carey E; Carlsson, Cynthia M; Johnson, Sterling C

2016-08-01

The ability to detect preclinical Alzheimer's disease is of great importance, as this stage of the Alzheimer's continuum is believed to provide a key window for intervention and prevention. As Alzheimer's disease is characterized by multiple pathological changes, a biomarker panel reflecting co-occurring pathology will likely be most useful for early detection. Towards this end, 175 late middle-aged participants (mean age 55.9 ± 5.7 years at first cognitive assessment, 70% female) were recruited from two longitudinally followed cohorts to undergo magnetic resonance imaging and lumbar puncture. Cluster analysis was used to group individuals based on biomarkers of amyloid pathology (cerebrospinal fluid amyloid-β42/amyloid-β40 assay levels), magnetic resonance imaging-derived measures of neurodegeneration/atrophy (cerebrospinal fluid-to-brain volume ratio, and hippocampal volume), neurofibrillary tangles (cerebrospinal fluid phosphorylated tau181 assay levels), and a brain-based marker of vascular risk (total white matter hyperintensity lesion volume). Four biomarker clusters emerged consistent with preclinical features of (i) Alzheimer's disease; (ii) mixed Alzheimer's disease and vascular aetiology; (iii) suspected non-Alzheimer's disease aetiology; and (iv) healthy ageing. Cognitive decline was then analysed between clusters using longitudinal assessments of episodic memory, semantic memory, executive function, and global cognitive function with linear mixed effects modelling. Cluster 1 exhibited a higher intercept and greater rates of decline on tests of episodic memory. Cluster 2 had a lower intercept on a test of semantic memory and both Cluster 2 and Cluster 3 had steeper rates of decline on a test of global cognition. Additional analyses on Cluster 3, which had the smallest hippocampal volume, suggest that its biomarker profile is more likely due to hippocampal vulnerability and not to detectable specific volume loss exceeding the rate of normal ageing. Our results demonstrate that pathology, as indicated by biomarkers, in a preclinical timeframe is related to patterns of longitudinal cognitive decline. Such biomarker patterns may be useful for identifying at-risk populations to recruit for clinical trials. © The Author (2016). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Time-of-flight secondary ion mass spectrometry (ToF-SIMS)-based analysis and imaging of polyethylene microplastics formation during sea surf simulation.

PubMed

Jungnickel, H; Pund, R; Tentschert, J; Reichardt, P; Laux, P; Harbach, H; Luch, A

2016-09-01

Plastic particles smaller than 5mm, so called microplastics have the capability to accumulate in rivers, lakes and the marine environment and therefore have begun to be considered in eco-toxicology and human health risk assessment. Environmental microplastic contaminants may originate from consumer products like body wash, tooth pastes and cosmetic products, but also from degradation of plastic waste; they represent a potential but unpredictable threat to aquatic organisms and possibly also to humans. We investigated exemplarily for polyethylene (PE), the most abundant constituent of microplastic particles in the environment, whether such fragments could be produced from larger pellets (2mm×6mm). So far only few analytical methods exist to identify microplastic particles smaller than 10μm, especially no imaging mass spectrometry technique. We used at first time-of-flight secondary ion mass spectrometry (ToF-SIMS) for analysis and imaging of small PE-microplastic particles directly in the model system Ottawa sand during exposure to sea surf simulation. As a prerequisite, a method for identification of PE was established by identification of characteristic ions for PE out of an analysis of grinded polymer samples. The method was applied onto Ottawa sand in order to investigate the influence of simulated environmental conditions on particle transformation. A severe degradation of the primary PE pellet surface, associated with the transformation of larger particles into smaller ones already after 14days of sea surf simulation, was observed. Within the subsequent period of 14days to 1month of exposure the number of detected smallest-sized particles increased significantly (50%) while the second smallest fraction increased even further to 350%. Results were verified using artificially degraded PE pellets and Ottawa sand. Copyright © 2016 Elsevier B.V. All rights reserved.

Endotoxin in Size-Separated Metal Working Fluid Aerosol Particles.

PubMed

Dahlman-Höglund, Anna; Lindgren, Åsa; Mattsby-Baltzer, Inger

2016-08-01

Patients with airway symptoms working in metal working industries are increasing, despite efforts to improve the environmental air surrounding the machines. Our aim was to analyse the amount of endotoxin in size-separated airborne particles of metal working fluid (MWF) aerosol, by using the personal sampler Sioutas cascade impactor, to compare filter types, and to compare the concentration of airborne endotoxin to that of the corresponding MWFs. In a pilot field study, aerosols were collected in two separate machine halls on totally 10 occasions, using glass fibre and polytetrafluoroethylene (PTFE) filters in parallel at each station. Airborne endotoxin was distributed over all size fractions. While a major part was found in the largest size fraction (72%, 2.5-10 µm), up to 8% of the airborne endotoxin was detected in the smallest size fraction (<0.25 µm). Comparing the efficiency of the filter types, a significantly higher median endotoxin level was found with glass fibres filters collecting the largest particle-size fraction (1.2-fold) and with PTFE filters collecting the smallest ones (5-fold). The levels of endotoxin in the size-separated airborne particle fractions correlated to those of the MWFs supporting the aerosol-generating machines. Our study indicates that a significant part of inhalable aerosols of MWFs consists of endotoxin-containing particles below the size of intact bacteria, and thus small enough to readily reach the deepest part of the lung. Combined with other chemical irritants of the MWF, exposure to MWF aerosols containing endotoxin pose a risk to respiratory health problems. © The Author 2016. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.

A metabolomic study of low estimated GFR in non-proteinuric type 2 diabetes mellitus.

PubMed

Ng, D P K; Salim, A; Liu, Y; Zou, L; Xu, F G; Huang, S; Leong, H; Ong, C N

2012-02-01

We carried out a urinary metabolomic study to gain insight into low estimated GFR (eGFR) in patients with non-proteinuric type 2 diabetes. Patients were identified as being non-proteinuric using multiple urinalyses. Cases (n = 44) with low eGFR and controls (n = 46) had eGFR values <60 and ≥60 ml min(-1) 1.73 m(-2), respectively, as calculated using the Modification of Diet in Renal Disease formula. Urine samples were analysed by liquid chromatography/mass spectrometry (LC/MS) and GC/MS. False discovery rates were used to adjust for multiple hypotheses testing, and selection of metabolites that best predicted low eGFR status was achieved using least absolute shrinkage and selection operator logistic regression. Eleven GC/MS metabolites were strongly associated with low eGFR after correction for multiple hypotheses testing (smallest adjusted p value = 2.62 × 10(-14), largest adjusted p value = 3.84 × 10(-2)). In regression analysis, octanol, oxalic acid, phosphoric acid, benzamide, creatinine, 3,5-dimethoxymandelic amide and N-acetylglutamine were selected as the best subset for prediction and allowed excellent classification of low eGFR (AUC = 0.996). In LC/MS, 19 metabolites remained significant after multiple hypotheses testing had been taken into account (smallest adjusted p value = 2.04 × 10(-4), largest adjusted p value = 4.48 × 10(-2)), and several metabolites showed stronger evidence of association relative to the uraemic toxin, indoxyl sulphate (adjusted p value = 3.03 × 10(-2)). The potential effect of confounding on the association between metabolites was excluded. Our study has yielded substantial new insight into low eGFR and provided a collection of potential urinary biomarkers for its detection.

Vertical gradients in species richness and community composition across the twilight zone in the North Pacific Subtropical Gyre.

PubMed

Sommer, Stephanie A; Van Woudenberg, Lauren; Lenz, Petra H; Cepeda, Georgina; Goetze, Erica

2017-11-01

Although metazoan animals in the mesopelagic zone play critical roles in deep pelagic food webs and in the attenuation of carbon in midwaters, the diversity of these assemblages is not fully known. A metabarcoding survey of mesozooplankton diversity across the epipelagic, mesopelagic and upper bathypelagic zones (0-1500 m) in the North Pacific Subtropical Gyre revealed far higher estimates of species richness than expected given prior morphology-based studies in the region (4,024 OTUs, 10-fold increase), despite conservative bioinformatic processing. Operational taxonomic unit (OTU) richness of the full assemblage peaked at lower epipelagic-upper mesopelagic depths (100-300 m), with slight shoaling of maximal richness at night due to diel vertical migration, in contrast to expectations of a deep mesopelagic diversity maximum as reported for several plankton groups in early systematic and zoogeographic studies. Four distinct depth-stratified species assemblages were identified, with faunal transitions occurring at 100 m, 300 m and 500 m. Highest diversity occurred in the smallest zooplankton size fractions (0.2-0.5 mm), which had significantly lower % OTUs classified due to poor representation in reference databases, suggesting a deep reservoir of poorly understood diversity in the smallest metazoan animals. A diverse meroplankton assemblage also was detected (350 OTUs), including larvae of both shallow and deep living benthic species. Our results provide some of the first insights into the hidden diversity present in zooplankton assemblages in midwaters, and a molecular reappraisal of vertical gradients in species richness, depth distributions and community composition for the full zooplankton assemblage across the epipelagic, mesopelagic and upper bathypelagic zones. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

Specific Skin Lesions of Sarcoidosis Located at Venipuncture Points for Blood Sample Collection.

PubMed

Marcoval, Joaquim; Penín, Rosa M; Mañá, Juan

2018-05-01

It has been suggested that the predilection of sarcoidosis to affect scars is due to the presence of antigens or foreign bodies that can serve as a stimulus for granuloma formation. Several patients with sarcoidosis-specific skin lesions in venous puncture sites have been reported. However, in these patients the pathogenesis of the cutaneous lesions is not clear because the presence of foreign bodies is not to be expected. Our objective was to describe 3 patients who developed specific lesions of sarcoidosis in areas of venipuncture and to discuss their possible pathogenesis. The database of the Sarcoid Clinic of Bellvitge Hospital (an 800-bed university referral center providing tertiary care to approximately 1 million people in Barcelona, Spain) was reviewed to detect those patients with specific cutaneous lesions of systemic sarcoidosis in areas of venipuncture. Three patients with biopsy-proven specific cutaneous lesions of systemic sarcoidosis in areas of venipuncture for blood collection were detected (3 women, mean age 56 years). In one case, the histopathological image shows the hypothetical path of a needle through the skin. In 2 cases, an amorphous birefringent material was detected under polarized light. This material was consistent with silicone. In patients who are developing sarcoidosis, the smallest amount of oil used as lubricant in the needle for sample blood collection may induce the formation of granulomas. In addition to exploring scars, it is advisable to explore the cubital folds to detect specific cutaneous lesions of sarcoidosis.

Novel fiber optic sensor probe with a pair of highly reflected connectors and a vessel of water absorption material for water leak detection.

PubMed

Cho, Tae-Sik; Choi, Ki-Sun; Seo, Dae-Cheol; Kwon, Il-Bum; Lee, Jung-Ryul

2012-01-01

The use of a fiber optic quasi-distributed sensing technique for detecting the location and severity of water leakage is suggested. A novel fiber optic sensor probe is devised with a vessel of water absorption material called as water combination soil (WCS) located between two highly reflected connectors: one is a reference connector and the other is a sensing connector. In this study, the sensing output is calculated from the reflected light signals of the two connectors. The first reflected light signal is a reference and the second is a sensing signal which is attenuated by the optical fiber bending loss due to the WCS expansion absorbing water. Also, the bending loss of each sensor probe is determined by referring to the total number of sensor probes and the total power budget of an entire system. We have investigated several probe characteristics to show the design feasibility of the novel fiber sensor probe. The effects of vessel sizes of the probes on the water detection sensitivity are studied. The largest vessel probe provides the highest sensitivity of 0.267 dB/mL, while the smallest shows relatively low sensitivity of 0.067 dB/mL, and unstable response. The sensor probe with a high output value provides a high sensitivity with various detection levels while the number of total installable sensor probes decreases.

A new full-field interferometry approach for counting and differentiating aquatic biotic nanoparticles (Conference Presentation)

NASA Astrophysics Data System (ADS)

Boccara, A. Claude; Fedala, Yasmina; Voronkoff, Justine; Paffoni, Nina; Boccara, Martine

2017-03-01

Due to the huge abundance and the major role that viruses and membrane vesicles play in the seas or rivers ecosystems it is necessary to develop simple, sensitive, compact and reliable methods for their detection and characterization. Our approach is based on the measurement of the weak light level scattered by the biotic nanoparticles. We describe a new full-field, incoherently illuminated, shot-noise limited, common-path interferometric detection method coupled with the analysis of Brownian motion to detect, quantify, and differentiate biotic nanoparticles. The last developments take advantage of a new fast (700 Hz) camera with 2 Me- full well capacity that improves the signal to noise ratio and increases the precision of the Brownian motion characterization. We validated the method with calibrated nanoparticles and homogeneous DNA or RNA.viruses. The smallest virus size that we characterized with a suitable signal-to-noise ratio was around 30 nm in diameter with a target towards the numerous 20 nm diameter viruses. We show for the first time anisotropic trajectories for myoviruses meaning that there is a memory of the initial direction of their Brownian motions. Significant improvements have been made in the handling of the sample as well as in the statistical analysis for differentiating the various families of vesicles and virus. We further applied the method for vesicles detection and for analysis of coastal and oligotrophic samples from Tara Oceans circumnavigation as well of various rivers.

NEAR-INFRARED THERMAL EMISSION FROM THE HOT JUPITER TrES-2b: GROUND-BASED DETECTION OF THE SECONDARY ECLIPSE

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

Croll, Bryce; Jayawardhana, Ray; Albert, Loic

2010-07-10

We present near-infrared Ks-band photometry bracketing the secondary eclipse of the hot Jupiter TrES-2b using the Wide-field Infrared Camera on the Canada-France-Hawaii Telescope. We detect its thermal emission with an eclipse depth of 0.062{sup +0.013}{sub -0.011}% (5{sigma}). Our best-fit secondary eclipse is consistent with a circular orbit (a 3{sigma} upper limit on the eccentricity, e, and argument or periastron, {omega}, of |e cos {omega}| < 0.0090), in agreement with mid-infrared detections of the secondary eclipse of this planet. A secondary eclipse of this depth corresponds to a dayside Ks-band brightness temperature of T{sub B} = 1636{sup +79}{sub -88} K. Ourmore » thermal emission measurement, when combined with the thermal emission measurements using Spitzer/IRAC from O'Donovan and collaborators, suggests that this planet exhibits relatively efficient dayside to nightside redistribution of heat and a near isothermal dayside atmospheric temperature structure, whose spectrum is well approximated by a blackbody. It is unclear if the atmosphere of TrES-2b requires a temperature inversion; if it does it is likely due to chemical species other than TiO/VO as the atmosphere of TrES-2b is too cool to allow TiO/VO to remain in gaseous form. Our secondary eclipse has the smallest depth of any detected from the ground, at around 2 {mu}m, to date.« less

[Detection of intraorbital foreign material using MDCT].

PubMed

Hoffstetter, P; Friedrich, C; Framme, C; Hoffstetter, M; Zorger, N; Stierstorfer, K; Ross, C; Uller, W; Müller-Wille, R; Rennert, J; Jung, E M; Schreyer, A G

2011-06-01

To judge the possibilities of detection of orbital foreign bodies in multidetector CT (MDCT) with a focus on glass slivers. Experimental systematic measuring of Hounsfield Units (HU) of 20 different materials, containing 16 different types of glass with 4 different types of ophthalmic lenses among them. The measurements were performed using a standardized protocol with an orbita phantom being scanned with 16-slice MDCT. Using the resulting density values, the smallest detectable volume was calculated. Using this data we produced slivers of 5 different glass types in the sub-millimeter range and calculated their volume. Those micro-slivers underwent another CT scan using the same protocol as mentioned above to experimentally discern and confirm the detection limit for micro-slivers made of different materials. Glass has comparatively high density values of at least 2000 HU. The density of glasses with strong refraction is significantly higher and reaches up to 12 400 HU. We calculated a minimum detectable volume of 0.07 mm (3) for glass with a density of 2000 HU. Only glass slivers with a density higher than 8300 HU were experimentally detectable in the sub-millimeter range up to a volume as small as 0.01 mm (3). Less dense glass slivers could not be seen, even though their volume was above the theoretically calculated threshold for detection. Due to its high density of at least 2000 HU, glass is usually easily recognizable as an orbital foreign body. The detection threshold depends on the object's density and size and can be as low as 0.01 mm (3) in the case of glass with strong refraction and thus high density. The detection of glass as an orbital foreign body seems to be secure for slivers with a volume of at least 0.2 mm (3) for all types of glass. © Georg Thieme Verlag KG Stuttgart · New York.

Hot Spot Detection System Using Landsat 8/OLI Data

NASA Astrophysics Data System (ADS)

Kato, S.; Nakamura, R.; Oda, A.; Iijima, A.; Kouyama, T.; Iwata, T.

2015-12-01

We developed a simple algorithm and a Web-based visualizing system to detect hot spots using Landsat 8 OLI multispectral data as one of the applications of the real-time processing of Landsat 8 data. An empirical equation and radiometric and reflective thresholds were derived to detect hot spots using the OLI data at band 5 (0.865 μm) and band 7 (2.200 μm) based on the increase in spectral radiance at shortwave infrared (SWIR) region due to the emission from objects with high surface temperature. We surveyed typical patterns of surface spectra using the ASTER spectral library to delineate a threshold to distinguish hot spots from background surfaces. To adjust the empirical coefficients of our detection algorithm, we visually inspected the detected hot spots using 6593 Landsat 8 scenes, which cover eastern part of East Asia, taken from January 1, 2014 to December 31, 2014, displayed on a dedicated Web GIS system. Eventually we determined threshold equations which can theoretically detect hot spots at temperatures above 230 °C over isothermal pixels and hot spots as small as 1 m2 at temperatures of 1000 °C as the lowest temperature and the smallest subpixel coverage, respectively, for daytime scenes. The algorithm detected hot spots including wildfires, volcanos, open burnings and factories. 30-m spatial resolution of Landsat 8 enabled to detect wild fires and open burnings accompanied by clearer shapes of fire front lines than MODIS and VIIRS fire products. Although the 16-day revisit cycle of Landsat 8 is too long to effectively find unexpected wildfire or outbreak of eruption, the revisit cycle is enough to monitor temporally stable heat sources, such as continually erupting volcanos and factories. False detection was found over building rooftops, which have relatively smooth surfaces at longer wavelengths, when specular reflection occurred at the satellite overpass.

Can you hear me now? Range-testing a submerged passive acoustic receiver array in a Caribbean coral reef habitat

USGS Publications Warehouse

Selby, Thomas H.; Hart, Kristen M.; Fujisaki, Ikuko; Smith, Brian J.; Pollock, Clayton J; Hillis-Star, Zandy M; Lundgren, Ian; Oli, Madan K.

2016-01-01

Submerged passive acoustic technology allows researchers to investigate spatial and temporal movement patterns of many marine and freshwater species. The technology uses receivers to detect and record acoustic transmissions emitted from tags attached to an individual. Acoustic signal strength naturally attenuates over distance, but numerous environmental variables also affect the probability a tag is detected. Knowledge of receiver range is crucial for designing acoustic arrays and analyzing telemetry data. Here, we present a method for testing a relatively large-scale receiver array in a dynamic Caribbean coastal environment intended for long-term monitoring of multiple species. The U.S. Geological Survey and several academic institutions in collaboration with resource management at Buck Island Reef National Monument (BIRNM), off the coast of St. Croix, recently deployed a 52 passive acoustic receiver array. We targeted 19 array-representative receivers for range-testing by submersing fixed delay interval range-testing tags at various distance intervals in each cardinal direction from a receiver for a minimum of an hour. Using a generalized linear mixed model (GLMM), we estimated the probability of detection across the array and assessed the effect of water depth, habitat, wind, temperature, and time of day on the probability of detection. The predicted probability of detection across the entire array at 100 m distance from a receiver was 58.2% (95% CI: 44.0–73.0%) and dropped to 26.0% (95% CI: 11.4–39.3%) 200 m from a receiver indicating a somewhat constrained effective detection range. Detection probability varied across habitat classes with the greatest effective detection range occurring in homogenous sand substrate and the smallest in high rugosity reef. Predicted probability of detection across BIRNM highlights potential gaps in coverage using the current array as well as limitations of passive acoustic technology within a complex coral reef environment.

Scales drive detection, attention, and memory of snakes in wild vervet monkeys (Chlorocebus pygerythrus).

PubMed

Isbell, Lynne A; Etting, Stephanie F

2017-01-01

Predatory snakes are argued to have been largely responsible for the origin of primates via selection favoring expansion of the primate visual system, and even today snakes can be deadly to primates. Neurobiological research is now beginning to reveal the mechanisms underlying the ability of primates (including humans) to detect snakes more rapidly than other stimuli. However, the visual cues allowing rapid detection of snakes, and the cognitive and ecological conditions contributing to faster detection, are unclear. Since snakes are often partially obscured by vegetation, the more salient cues are predicted to occur in small units. Here we tested for the salience of snake scales as the smallest of potential visual cues by presenting four groups of wild vervet monkeys (Chlorocebus pytherythrus) with a gopher snake (Pituophis catenifer) skin occluded except for no more than 2.7 cm, in natural form and flat, the latter to control for even small curvilinear cues from their unusual body shape. Each of these treatments was preceded by a treatment without the snakeskin, the first to provide a baseline, and the second, to test for vigilance and memory recall after exposure to the snakeskin. We found that (1) vervets needed only a small portion of snakeskin for detection, (2) snake scales alone were sufficient for detection, (3) latency to detect the snakeskin was longer with more extensive and complex ground cover, and (4) vervets that were exposed to the snakeskin remembered where they last saw "snakes", as indicated by increased wariness near the occluding landmarks in the absence of the snakeskin and more rapid detection of the next presented snakeskin. Unexpectedly, adult males did not detect the snakeskin as well as adult females and juveniles. These findings extend our knowledge of the complex ecological and evolutionary relationships between snakes and primates.

Fuel deposition rates of montane and subalpine conifers in the central Sierra Nevada, California, USA

USGS Publications Warehouse

van Wagtendonk, J.W.; Moore, P.E.

2010-01-01

Fire managers and researchers need information on fuel deposition rates to estimate future changes in fuel bed characteristics, determine when forests transition to another fire behavior fuel model, estimate future changes in fuel bed characteristics, and parameterize and validate ecosystem process models. This information is lacking for many ecosystems including the Sierra Nevada in California, USA. We investigated fuel deposition rates and stand characteristics of seven montane and four subalpine conifers in the Sierra Nevada. We collected foliage, miscellaneous bark and crown fragments, cones, and woody fuel classes from four replicate plots each in four stem diameter size classes for each species, for a total of 176 sampling sites. We used these data to develop predictive equations for each fuel class and diameter size class of each species based on stem and crown characteristics. There were consistent species and diameter class differences in the annual amount of foliage and fragments deposited. Foliage deposition rates ranged from just over 50 g m-2 year-1 in small diameter mountain hemlock stands to ???300 g m-2 year-1 for the three largest diameter classes of giant sequoia. The deposition rate for most woody fuel classes increased from the smallest diameter class stands to the largest diameter class stands. Woody fuel deposition rates varied among species as well. The rates for the smallest woody fuels ranged from 0.8 g m-2 year-1 for small diameter stands of Jeffrey pine to 126.9 g m-2 year-1 for very large diameter stands of mountain hemlock. Crown height and live crown ratio were the best predictors of fuel deposition rates for most fuel classes and species. Both characteristics reflect the amount of crown biomass including foliage and woody fuels. Relationships established in this study allow predictions of fuel loads to be made on a stand basis for each of these species under current and possible future conditions. These predictions can be used to estimate fuel treatment longevity, assist in determining fuel model transitions, and predict future changes in fuel bed characteristics.

Cause-specific sickness absence trends by occupational class and industrial sector in the context of recent labour market changes: a Finnish panel data study.

PubMed

Leinonen, Taina; Viikari-Juntura, Eira; Husgafvel-Pursiainen, Kirsti; Solovieva, Svetlana

2018-04-07

We aimed to provide previously unestablished information on population-based differences in cause-specific sickness absence trends between occupational classes and further between four large industrial sectors within the different occupational classes while controlling for other socioeconomic factors and employment patterns. We focused on the period 2005-2013, during which the labour market underwent large economic and structural changes in many countries. Register-based panel data study. Large representative datasets on Finnish wage earners aged 25-59 years. Annual risk of sickness absence (>10 working days) based on repeated logistic regression. Between 2005 and 2013, the proportion of employees with sickness absence decreased. Occupational class differences in sickness absence trends varied by disease group. Overall, the decrease in absences was smallest among lower non-manual employees. Sickness absence levels were highest in the health and social work sector and in the manufacturing sector within the non-manual and manual classes, respectively. Absences due to musculoskeletal diseases decreased temporarily during the peak of the economic recession in 2009, particularly in the manufacturing sector within the manual class. The decrease in absences due to musculoskeletal diseases was smallest in the trade sector within the lower occupational classes. Overall, education, income and employment patterns partly explained the differences in the absence levels, but not in the trends. We found a complex interplay between the associations of occupational class and industrial sector with sickness absence trends. During the economic recession, absences due to musculoskeletal diseases decreased temporarily in a segment of wage earners who were known to have been hit hard by the recession. However, the trend differences were not explained by the measured structural changes in the characteristics of the study population. Both occupational class and industrial sector should be taken into account when tackling problems of work disability. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Attributing runoff changes to climate variability and human activities: uncertainty analysis using four monthly water balance models

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

Li, Shuai; Xiong, Lihua; Li, Hong-Yi

2015-05-26

Hydrological simulations to delineate the impacts of climate variability and human activities are subjected to uncertainties related to both parameter and structure of the hydrological models. To analyze the impact of these uncertainties on the model performance and to yield more reliable simulation results, a global calibration and multimodel combination method that integrates the Shuffled Complex Evolution Metropolis (SCEM) and Bayesian Model Averaging (BMA) of four monthly water balance models was proposed. The method was applied to the Weihe River Basin (WRB), the largest tributary of the Yellow River, to determine the contribution of climate variability and human activities tomore » runoff changes. The change point, which was used to determine the baseline period (1956-1990) and human-impacted period (1991-2009), was derived using both cumulative curve and Pettitt’s test. Results show that the combination method from SCEM provides more skillful deterministic predictions than the best calibrated individual model, resulting in the smallest uncertainty interval of runoff changes attributed to climate variability and human activities. This combination methodology provides a practical and flexible tool for attribution of runoff changes to climate variability and human activities by hydrological models.« less

Comparative Evaluation of Dimensional Accuracy of Elastomeric Impression Materials when Treated with Autoclave, Microwave, and Chemical Disinfection

PubMed Central

Kamble, Suresh S; Khandeparker, Rakshit Vijay; Somasundaram, P; Raghav, Shweta; Babaji, Rashmi P; Varghese, T Joju

2015-01-01

Background: Impression materials during impression procedure often get infected with various infectious diseases. Hence, disinfection of impression materials with various disinfectants is advised to protect the dental team. Disinfection can alter the dimensional accuracy of impression materials. The present study was aimed to evaluate the dimensional accuracy of elastomeric impression materials when treated with different disinfectants; autoclave, chemical, and microwave method. Materials and Methods: The impression materials used for the study were, dentsply aquasil (addition silicone polyvinylsiloxane syringe and putty), zetaplus (condensation silicone putty and light body), and impregum penta soft (polyether). All impressions were made according to manufacturer’s instructions. Dimensional changes were measured before and after different disinfection procedures. Result: Dentsply aquasil showed smallest dimensional change (−0.0046%) and impregum penta soft highest linear dimensional changes (−0.026%). All the tested elastomeric impression materials showed some degree of dimensional changes. Conclusion: The present study showed that all the disinfection procedures produce minor dimensional changes of impression material. However, it was within American Dental Association specification. Hence, steam autoclaving and microwave method can be used as an alternative method to chemical sterilization as an effective method. PMID:26435611

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

Simon, Amy A.; Wong, Michael H.; De Pater, Imke

Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features. Since the advent of modern telescopes, keen observers have noted its appearance and documented a change in shape from very oblong to oval, confirmed in measurements from spacecraft data. It currently spans the smallest latitude and longitude size ever recorded. Here we show that this change has been accompanied by an increase in cloud/haze reflectance as sensed in methane gas absorption bands, increased absorption at wavelengths shorter than 500 nm, and increased spectral slope between 500 and 630 nm. These changes occurred between 2012 and 2014, without amore » significant change in internal tangential wind speeds; the decreased size results in a 3.2 day horizontal cloud circulation period, shorter than previously observed. As the GRS has narrowed in latitude, it interacts less with the jets flanking its north and south edges, perhaps allowing for less cloud mixing and longer UV irradiation of cloud and aerosol particles. Given its long life and observational record, we expect that future modeling of the GRS's changes, in concert with laboratory flow experiments, will drive our understanding of vortex evolution and stability in a confined flow field crucial for comparison with other planetary atmospheres.« less

A detection algorithm for scale analysis of post-sunset low-latitude plasma depletions as observed by the Swarm constellation mission

NASA Astrophysics Data System (ADS)

Kervalishvili, Guram; Stolle, Claudia; Xiong, Chao

2016-04-01

ESA's constellation mission Swarm was successfully launched on 22 November 2013. The three satellites achieved their final constellation on 17 April 2014 and since then Swarm-A and Swarm-C orbiting the Earth at about 470 km (flying side-by-side) and Swarm-B at about 520 km altitude. The satellites carry instruments to monitor the F-region electron density with a sampling frequency of 2 Hz. This paper will present a detection algorithm for low-latitude post-sunset plasma bubbles (depletions), which uses local minima and maxima to detect depletions directly from electron density readings from Swarm. Our analyses were performed in the magnetic latitude (MLat) and local time (MLT) coordinate system. The detection procedure also captures the amplitude of depletion, which is called depth in the following. The width of a bubble corresponds to the length the satellite is located inside a depletion. We discuss the global distribution of depth and width of plasma bubbles and its seasonal and local time dependence for all three Swarm satellites from April 2015 through September 2015. As expected, on global average the bubble occurrence rate is highest for combined equinoxes (Mar, Apr, Sep, and Oct) and smallest for June solstice (May, Jun, Jul, and Aug). MLT distribution of the bubble occurrence number shows a sharp increase at about 19 MLT and decreases towards post-midnight hours. Interestingly, there is an inverse relation between depth and width of bubbles as function of MLT. This is true for all seasons and for all Swarm satellites. The bubble depth (width) is decreasing (increasing) from post-sunset to post-midnight for December solstice (Jan, Feb, Nov, and Dec) and combined equinoxes with about the same amplitude values for bubbles depth (width). Therefore we suggest that at post midnight when the depletions are less steep the structures of the depletions is broader than early after sunset. However for June solstice the depletions are less deep and the bubble depth and width do not change significantly throughout the evening. Deepest depletions occur at around +/- 10° magnetic latitude that is at the inner edge of the ionisation anomaly with density maxima at around 15° MLat. Therefore, the level of background electron density does not only determine the depth of a post-sunset depletion.

Grapevine acclimation to water deficit: the adjustment of stomatal and hydraulic conductance differs from petiole embolism vulnerability.

PubMed

Hochberg, Uri; Bonel, Andrea Giulia; David-Schwartz, Rakefet; Degu, Asfaw; Fait, Aaron; Cochard, Hervé; Peterlunger, Enrico; Herrera, Jose Carlos

2017-06-01

Drought-acclimated vines maintained higher gas exchange compared to irrigated controls under water deficit; this effect is associated with modified leaf turgor but not with improved petiole vulnerability to cavitation. A key feature for the prosperity of plants under changing environments is the plasticity of their hydraulic system. In the present research we studied the hydraulic regulation in grapevines (Vitis vinifera L.) that were first acclimated for 39 days to well-watered (WW), sustained water deficit (SD), or transient-cycles of dehydration-rehydration-water deficit (TD) conditions, and then subjected to varying degrees of drought. Vine development under SD led to the smallest leaves and petioles, but the TD vines had the smallest mean xylem vessel and calculated specific conductivity (k ts ). Unexpectedly, both the water deficit acclimation treatments resulted in vines more vulnerable to cavitation in comparison to WW, possibly as a result of developmental differences or cavitation fatigue. When exposed to drought, the SD vines maintained the highest stomatal (g s ) and leaf conductance (k leaf ) under low stem water potential (Ψ s ), despite their high xylem vulnerability and in agreement with their lower turgor loss point (Ψ TLP ). These findings suggest that the down-regulation of k leaf and g s is not associated with embolism, and the ability of drought-acclimated vines to maintain hydraulic conductance and gas exchange under stressed conditions is more likely associated with the leaf turgor and membrane permeability.

Comparison between medial rectus pulley fixation and augmented recession in children with convergence excess and variable-angle infantile esotropia.

PubMed

Fouad, Heba M; Abdelhakim, Mohamad A; Awadein, Ahmed; Elhilali, Hala

2016-10-01

To compare the outcomes of medial rectus (MR) muscle pulley fixation and augmented recession in children with convergence excess esotropia and variable-angle infantile esotropia. This was a prospective randomized interventional study in which children with convergence excess esotropia or variable-angle infantile esotropia were randomly allocated to either augmented MR muscle recession (augmented group) or MR muscle pulley posterior fixation (pulley group). In convergence excess, the MR recession was based on the average of distance and near angles of deviation with distance correction in the augmented group, and on the distance angle of deviation in the pulley group. In variable-angle infantile esotropia, the MR recession was based on the average of the largest and smallest angles in the augmented group and on the smallest angle in the pulley group. Pre- and postoperative ductions, versions, pattern strabismus, smallest and largest angles of deviation, and angle disparity were analyzed. Surgery was performed on 60 patients: 30 underwent bilateral augmented MR recession, and 30 underwent bilateral MR recession with pulley fixation. The success rate was statistically significantly higher (P = 0.037) in the pulley group (70%) than in the augmented group (40%). The postoperative smallest and largest angles and the angle disparity were statistically significantly lower in the pulley group than the augmented group (P < 0.01). Medial rectus muscle pulley fixation is a useful surgical step for addressing marked variability of the angle in variable angle esotropia and convergence excess esotropia. Copyright © 2016 American Association for Pediatric Ophthalmology and Strabismus. Published by Elsevier Inc. All rights reserved.

Capacitor-Chain Successive-Approximation ADC

NASA Technical Reports Server (NTRS)

Cunningham, Thomas

2003-01-01

A proposed successive-approximation analog-to-digital converter (ADC) would contain a capacitively terminated chain of identical capacitor cells. Like a conventional successive-approximation ADC containing a bank of binary-scaled capacitors, the proposed ADC would store an input voltage on a sample-and-hold capacitor and would digitize the stored input voltage by finding the closest match between this voltage and a capacitively generated sum of binary fractions of a reference voltage (Vref). However, the proposed capacitor-chain ADC would offer two major advantages over a conventional binary-scaled-capacitor ADC: (1) In a conventional ADC that digitizes to n bits, the largest capacitor (representing the most significant bit) must have 2(exp n-1) times as much capacitance, and hence, approximately 2(exp n-1) times as much area as does the smallest capacitor (representing the least significant bit), so that the total capacitor area must be 2(exp n) times that of the smallest capacitor. In the proposed capacitor-chain ADC, there would be three capacitors per cell, each approximately equal to the smallest capacitor in the conventional ADC, and there would be one cell per bit. Therefore, the total capacitor area would be only about 3(exp n) times that of the smallest capacitor. The net result would be that the proposed ADC could be considerably smaller than the conventional ADC. (2) Because of edge effects, parasitic capacitances, and manufacturing tolerances, it is difficult to make capacitor banks in which the values of capacitance are scaled by powers of 2 to the required precision. In contrast, because all the capacitors in the proposed ADC would be identical, the problem of precise binary scaling would not arise.

Designing Clinical Trials of Interventions for Mobility Disability: Results from the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P) Trial

PubMed Central

Espeland, Mark A.; Gill, Thomas M.; Guralnik, Jack; Miller, Michael E.; Fielding, Roger; Newman, Anne B.; Pahor, Marco

2008-01-01

Background Clinical trials to assess interventions for mobility disability are critically needed; however, data for efficiently designing such trials are lacking. Methods Results are described from a pilot clinical trial in which 424 volunteers aged 70–89 years were randomly assigned to one of two interventions -- physical activity or a healthy aging education program -- and followed for a planned minimum of 12 months. We evaluated the longitudinal distributions of four standardized outcomes to contrast how they may serve as primary outcomes of future clinical trials: ability to walk 400 meters, ability to walk 4 meters in ≤10 seconds, a physical performance battery, and a questionnaire focused on physical function. Results Changes in all four outcomes were inter-related over time. The ability to walk 400 meters as a dichotomous outcome provided the smallest sample size projections (i.e. appeared to be the most efficient outcome). It loaded most heavily on the underlying latent variable in structural equation modeling with a weight of 80%. A four-year trial based on the outcome of 400 meter walk is projected to require N = 962 to 2,234 to detect an intervention effect of 30% to 20% with 90% power. Conclusions Future clinical trials of interventions designed to influence mobility disability may have greater efficiency if they adopt the ability to complete a 400 meter walk as their primary outcome. PMID:18000143

High-resolution three-dimensional visualization of the rat spinal cord microvasculature by synchrotron radiation micro-CT

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

Hu, Jianzhong; Cao, Yong; Wu, Tianding

2014-10-15

Purpose: Understanding the three-dimensional (3D) morphology of the spinal cord microvasculature has been limited by the lack of an effective high-resolution imaging technique. In this study, synchrotron radiation microcomputed tomography (SRµCT), a novel imaging technique based on absorption imaging, was evaluated with regard to the detection of the 3D morphology of the rat spinal cord microvasculature. Methods: Ten Sprague-Dawley rats were used in this ex vivo study. After contrast agent perfusion, their spinal cords were isolated and scanned using conventional x-rays, conventional micro-CT (CµCT), and SRµCT. Results: Based on contrast agent perfusion, the microvasculature of the rat spinal cord wasmore » clearly visualized for the first time ex vivo in 3D by means of SRµCT scanning. Compared to conventional imaging techniques, SRµCT achieved higher resolution 3D vascular imaging, with the smallest vessel that could be distinguished approximately 7.4 μm in diameter. Additionally, a 3D pseudocolored image of the spinal cord microvasculature was generated in a single session of SRµCT imaging, which was conducive to detailed observation of the vessel morphology. Conclusions: The results of this study indicated that SRµCT scanning could provide higher resolution images of the vascular network of the spinal cord. This modality also has the potential to serve as a powerful imaging tool for the investigation of morphology changes in the 3D angioarchitecture of the neurovasculature in preclinical research.« less

Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping.

PubMed Central

Trask, B; van den Engh, G; Mayall, B; Gray, J W

1989-01-01

Maternal and paternal homologues of many chromosome types can be differentiated on the basis of their peak position in Hoechst 33258 versus chromomycin A3 bivariate flow karyotypes. We demonstrate here the magnitude of DNA content differences among normal chromosomes of the same type. Significant peak-position differences between homologues were observed for an average of four chromosome types in each of the karyotypes of 98 different individuals. The frequency of individuals with differences in homologue peak positions varied among chromosome types: e.g., chromosome 15, 61%; chromosome 3, 4%. Flow karyotypes of 33 unrelated individuals were compared to determine the range of peak position among normal chromosomes. Chromosomes Y, 21, 22, 15, 16, 13, 14, and 19 were most heteromorphic, and chromosomes 2-8 and X were least heteromorphic. The largest chromosome 21 was 45% larger than the smallest 21 chromosome observed. The base composition of the variable regions differed among chromosome types. DNA contents of chromosome variants determined from flow karyotypes were closely correlated to measurements of DNA content made of gallocyanin chrome alum-stained metaphase chromosomes on slides. Fluorescence in situ hybridization with chromosome-specific repetitive sequences indicated that variability in their copy number is partly responsible for peak-position variability in some chromosomes. Heteromorphic chromosomes are identified for which parental flow karyotype information will be essential if de novo rearrangements resulting in small DNA content changes are to be detected with flow karyotyping. Images Figure 5 PMID:2479266

Cross-cultural adaptation and validation of Persian Achilles tendon Total Rupture Score.

PubMed

Ansari, Noureddin Nakhostin; Naghdi, Soofia; Hasanvand, Sahar; Fakhari, Zahra; Kordi, Ramin; Nilsson-Helander, Katarina

2016-04-01

To cross-culturally adapt the Achilles tendon Total Rupture Score (ATRS) to Persian language and to preliminary evaluate the reliability and validity of a Persian ATRS. A cross-sectional and prospective cohort study was conducted to translate and cross-culturally adapt the ATRS to Persian language (ATRS-Persian) following steps described in guidelines. Thirty patients with total Achilles tendon rupture and 30 healthy subjects participated in this study. Psychometric properties of floor/ceiling effects (responsiveness), internal consistency reliability, test-retest reliability, standard error of measurement (SEM), smallest detectable change (SDC), construct validity, and discriminant validity were tested. Factor analysis was performed to determine the ATRS-Persian structure. There were no floor or ceiling effects that indicate the content and responsiveness of ATRS-Persian. Internal consistency was high (Cronbach's α 0.95). Item-total correlations exceeded acceptable standard of 0.3 for the all items (0.58-0.95). The test-retest reliability was excellent [(ICC)agreement 0.98]. SEM and SDC were 3.57 and 9.9, respectively. Construct validity was supported by a significant correlation between the ATRS-Persian total score and the Persian Foot and Ankle Outcome Score (PFAOS) total score and PFAOS subscales (r = 0.55-0.83). The ATRS-Persian significantly discriminated between patients and healthy subjects. Explanatory factor analysis revealed 1 component. The ATRS was cross-culturally adapted to Persian and demonstrated to be a reliable and valid instrument to measure functional outcomes in Persian patients with Achilles tendon rupture. II.

The feasibility and concurrent validity of performing the Movement Assessment Battery for Children - 2nd Edition via telerehabilitation technology.

PubMed

Nicola, Kristy; Waugh, Jemimah; Charles, Emily; Russell, Trevor

2018-06-01

In rural and remote communities children with motor difficulties have less access to rehabilitation services. Telerehabilitation technology is a potential method to overcome barriers restricting access to healthcare in these areas. Assessment is necessary to guide clinical reasoning; however it is unclear which paediatric assessments can be administered remotely. The Movement Assessment Battery for Children - 2nd Edition is commonly used by various health professionals to assess motor performance of children. The aim of this study was to investigate the feasibility and concurrent validity of performing the Movement Assessment Battery for Children - 2nd Edition remotely via telerehabilitation technology compared to the conventional in-person method. Fifty-nine children enrolled in a state school (5-11 years old) volunteered to perform one in-person and one telerehabilitation mediated assessment. The order of the method of delivery and the therapist performing the assessment were randomized. After both assessments were complete, a participant satisfaction questionnaire was completed by each child. The Bland-Altman limits of agreement for the total test standard score were -3.15 to 3.22 which is smaller than a pre-determined clinically acceptable margin based on the smallest detectable change. This study establishes the feasibility and concurrent validity of the administration of the Movement Assessment Battery for Children - 2nd Edition via telerehabilitation technology. Overall, participants perceived their experience with telerehabilitation positively. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Pain Self-Efficacy Questionnaire: Cross-Cultural Adaptation into Italian and Assessment of Its Measurement Properties.

PubMed

Chiarotto, Alessandro; Vanti, Carla; Ostelo, Raymond W; Ferrari, Silvano; Tedesco, Giuseppe; Rocca, Barbara; Pillastrini, Paolo; Monticone, Marco

2015-11-01

The Pain Self-Efficacy Questionnaire (PSEQ) is a patient self-reported measurement instrument that evaluates pain self-efficacy beliefs in patients with chronic pain. The measurement properties of the PSEQ have been tested in its original and translated versions, showing satisfactory results for validity and reliability. The aims of this study were 2 fold as follows: (1) to translate the PSEQ into Italian through a process of cross-cultural adaptation, (2) to test the measurement properties of the Italian PSEQ (PSEQ-I). The cross-cultural adaptation was completed in 5 months without omitting any item of the original PSEQ. Measurement properties were tested in 165 patients with chronic low back pain (CLBP) (65% women, mean age 49.9 years). Factor analysis confirmed the one-factor structure of the questionnaire. Internal consistency (Cronbach's α = 0.94) and test-retest reliability (ICCagreement  = 0.82) of the PSEQ-I showed good results. The smallest detectable change was equal to 15.69 scale points. The PSEQ-I displayed a high construct validity by meeting more than 75% of a priori hypotheses on correlations with measurement instruments assessing pain intensity, disability, anxiety, depression, pain catastrophizing, fear of movement, and coping strategies. Additionally, the PSEQ-I differentiated patients taking pain medication or not. The results of this study suggest that the PSEQ-I can be used as a valid and reliable tool in Italian patients with CLBP. © 2014 World Institute of Pain.

Isoflurane is a suitable alternative to ether for anesthetizing rats prior to euthanasia for gene expression analysis.

PubMed

Nakatsu, Noriyuki; Igarashi, Yoshinobu; Aoshi, Taiki; Hamaguchi, Isao; Saito, Masumichi; Mizukami, Takuo; Momose, Haruka; Ishii, Ken J; Yamada, Hiroshi

2017-01-01

Diethyl ether (ether) had been widely used in Japan for anesthesia, despite its explosive properties and toxicity to both humans and animals. We also had used ether as an anesthetic for euthanizing rats for research in the Toxicogenomics Project (TGP). Because the use of ether for these purposes will likely cease, it is required to select an alternative anesthetic which is validated for consistency with existing TGP data acquired under ether anesthesia. We therefore compared two alternative anesthetic candidates, isoflurane and pentobarbital, with ether in terms of hematological findings, serum biochemical parameters, and gene expressions. As a result, few differences among the three agents were observed. In hematological and serum biochemistry analysis, no significant changes were found. In gene expression analysis, four known genes were extracted as differentially expressed genes in the liver of rats anesthetized with ether, isoflurane, or pentobarbital. However, no significant relationships were detected using gene ontology, pathway, or gene enrichment analyses by DAVID and TargetMine. Surprisingly, although it was expected that the lung would be affected by administration via inhalation, only one differentially expressed gene was extracted in the lung. Taken together, our data indicate that there are no significant differences among ether, isoflurane, and pentobarbital with respect to effects on hematological parameters, serum biochemistry parameters, and gene expression. Based on its smallest affect to existing data and its safety profile for humans and animals, we suggest isoflurane as a suitable alternative anesthetic for use in rat euthanasia in toxicogenomics analysis.

Reliability analysis of a sensitive and independent stabilometry parameter set

PubMed Central

Nagymáté, Gergely; Orlovits, Zsanett

2018-01-01

Recent studies have suggested reduced independent and sensitive parameter sets for stabilometry measurements based on correlation and variance analyses. However, the reliability of these recommended parameter sets has not been studied in the literature or not in every stance type used in stabilometry assessments, for example, single leg stances. The goal of this study is to evaluate the test-retest reliability of different time-based and frequency-based parameters that are calculated from the center of pressure (CoP) during bipedal and single leg stance for 30- and 60-second measurement intervals. Thirty healthy subjects performed repeated standing trials in a bipedal stance with eyes open and eyes closed conditions and in a single leg stance with eyes open for 60 seconds. A force distribution measuring plate was used to record the CoP. The reliability of the CoP parameters was characterized by using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC), coefficient of variation (CV) and CV compliance rate (CVCR). Based on the ICC, SEM and MDC results, many parameters yielded fair to good reliability values, while the CoP path length yielded the highest reliability (smallest ICC > 0.67 (0.54–0.79), largest SEM% = 19.2%). Usually, frequency type parameters and extreme value parameters yielded poor reliability values. There were differences in the reliability of the maximum CoP velocity (better with 30 seconds) and mean power frequency (better with 60 seconds) parameters between the different sampling intervals. PMID:29664938

Reliability analysis of a sensitive and independent stabilometry parameter set.

PubMed

Nagymáté, Gergely; Orlovits, Zsanett; Kiss, Rita M

2018-01-01

Recent studies have suggested reduced independent and sensitive parameter sets for stabilometry measurements based on correlation and variance analyses. However, the reliability of these recommended parameter sets has not been studied in the literature or not in every stance type used in stabilometry assessments, for example, single leg stances. The goal of this study is to evaluate the test-retest reliability of different time-based and frequency-based parameters that are calculated from the center of pressure (CoP) during bipedal and single leg stance for 30- and 60-second measurement intervals. Thirty healthy subjects performed repeated standing trials in a bipedal stance with eyes open and eyes closed conditions and in a single leg stance with eyes open for 60 seconds. A force distribution measuring plate was used to record the CoP. The reliability of the CoP parameters was characterized by using the intraclass correlation coefficient (ICC), standard error of measurement (SEM), minimal detectable change (MDC), coefficient of variation (CV) and CV compliance rate (CVCR). Based on the ICC, SEM and MDC results, many parameters yielded fair to good reliability values, while the CoP path length yielded the highest reliability (smallest ICC > 0.67 (0.54-0.79), largest SEM% = 19.2%). Usually, frequency type parameters and extreme value parameters yielded poor reliability values. There were differences in the reliability of the maximum CoP velocity (better with 30 seconds) and mean power frequency (better with 60 seconds) parameters between the different sampling intervals.

Multiwavelength Monitoring of the Enigmatic Narrow-Line Seyfert 1 PMN J0948+0022 in 2009 March-July

DOE PAGES

Abdo, A. A.; Ackermann, M.; Ajello, M.; ...

2009-11-25

For this research, following the recent discovery of γ rays from the radio-loud narrow-line Seyfert 1 galaxy PMN J0948+0022 (z = 0.5846), we started a multiwavelength campaign from radio to γ rays, which was carried out between the end of 2009 March and the beginning of July. The source displayed activity at all the observed wavelengths: a general decreasing trend from optical to γ-ray frequencies was followed by an increase of radio emission after less than two months from the peak of the γ-ray emission. The largest flux change, about a factor of about 4, occurred in the X-ray band.more » The smallest was at ultraviolet and near-infrared frequencies, where the rate of the detected photons dropped by a factor 1.6-1.9. At optical wavelengths, where the sampling rate was the highest, it was possible to observe day scale variability, with flux variations up to a factor of about 3. The behavior of PMN J0948+0022 observed in this campaign and the calculated power carried out by its jet in the form of protons, electrons, radiation, and magnetic field are quite similar to that of blazars, specifically of flat-spectrum radio quasars. In conclusion, these results confirm the idea that radio-loud narrow-line Seyfert 1 galaxies host relativistic jets with power similar to that of average blazars.« less

Physiological and histological alterations in the bronchial mucociliary clearance system of rabbits following intermittent oral or nasal inhalation of sulfuric acid mist

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

Schlesinger, R.B.; Naumann, B.D.; Chen, L.C.

Rabbits were exposed to submicrometer sulfuric acid mist (H/sub 2/SO/sub 4/) for 1 h/d, 5 d/w for 4 wk, during which time mucociliary clearance was monitored by external in vivo measurements of tagged tracer aerosol retention. One group was exposed orally to 250 ..mu..g/m/sup 3/, another to the same concentration via the nose, and a third to 500 ..mu..g/m/sup 3/ also via nasal breathing. Clearance was accelerated on specific individual days during the course of the acid exposures, especially at 500 ..mu..g/m/sup 3/. In all series, clearance was significantly faster, compared to preexposure controls, during a 2-wk follow-up period aftermore » acid exposures had ceased. At the end of this period, the rabbits were sacrificed, and histological sections were obtained from the tracheobronchial tree. Significantly increased epithelial thickness of small conducting airways, compared to sham exposure controls, occurred in rabbits exposed orally at 250 ..mu..g/m/sup 3/ or nasally at 500 ..mu.., and additionally the lumen of the smallest airways of the former group was narrower than control. The number of airways containing epithelial secretory cells was also significantly greater in these acid exposure groups compared to sham controls. The only change in the rabbits exposed nasally at 250 ..mu..g/m/sup 3/ was a significant increase in the number of airways with epithelial secretory cells in the smallest airway classfication. Differences in site and degree of histological response and degree of physiological change between the two groups exposed to identical acid concentrations appear to have been due to differences in exposure mode, with resultant effects on breathing pattern, aerosol size distribution, and concentration penetrating beyond the upper respiratory tract to specific lung sites.« less

Task-induced Changes in Idiopathic Infantile Nystagmus Vary with Gaze.

PubMed

Salehi Fadardi, Marzieh; Bathke, Arne C; Harrar, Solomon W; Abel, Larry Allen

2017-05-01

Investigations of infantile nystagmus syndrome (INS) at center or at the null position have reported that INS worsens when visual demand is combined with internal states, e.g. stress. Visual function and INS parameters such as foveation time, frequency, amplitude, and intensity can also be influenced by gaze position. We hypothesized that increases from baseline in visual demand and mental load would affect INS parameters at the null position differently than at other gaze positions. Eleven participants with idiopathic INS were asked to determine the direction of Tumbling-E targets, whose visual demand was varied through changes in size and contrast, using a staircase procedure. Targets appeared between ±25° in 5° steps. The task was repeated with both mental arithmetic and time restriction to impose higher mental load, confirmed through subjective ratings and concurrent physiological measurements. Within-subject comparisons were limited to the null and 15° away from it. No significant main effects of task on any INS parameters were found. At both locations, high mental load worsened task performance metrics, i.e. lowest contrast (P = .001) and smallest optotype size reached (P = .012). There was a significant interaction between mental load and gaze position for foveation time (P = .02) and for the smallest optotype reached (P = .028). The increase in threshold optotype size from the low to high mental load was greater at the null than away from it. During high visual demand, foveation time significantly decreased from baseline at the null as compared to away from it (mean difference ± SE: 14.19 ± 0.7 msec; P = .010). Under high visual demand, the effects of increased mental load on foveation time and visual task performance differed at the null as compared to 15° away from it. Assessment of these effects could be valuable when evaluating INS clinically and when considering its impact on patients' daily activities.

Application of Aerosol Hygroscopicity Measured at the Atmospheric Radiation Measurement Program's Southern Great Plains Site to Examine Composition and Evolution

NASA Technical Reports Server (NTRS)

Gasparini, Roberto; Runjun, Li; Collins, Don R.; Ferrare, Richard A.; Brackett, Vincent G.

2006-01-01

A Differential Mobility Analyzer/Tandem Differential Mobility Analyzer (DMA/TDMA) was used to measure submicron aerosol size distributions, hygroscopicity, and occasionally volatility during the May 2003 Aerosol Intensive Operational Period (IOP) at the Central Facility of the Atmospheric Radiation Measurement Program's Southern Great Plains (ARM SGP) site. Hygroscopic growth factor distributions for particles at eight dry diameters ranging from 0.012 micrometers to 0.600 micrometers were measured throughout the study. For a subset of particle sizes, more detailed measurements were occasionally made in which the relative humidity or temperature to which the aerosol was exposed was varied over a wide range. These measurements, in conjunction with backtrajectory clustering, were used to infer aerosol composition and to gain insight into the processes responsible for evolution. The hygroscopic growth of both the smallest and largest particles analyzed was typically less than that of particles with dry diameters of about 0.100 micrometers. It is speculated that condensation of secondary organic aerosol on nucleation mode particles is largely responsible for the minimal hygroscopic growth observed at the smallest sizes considered. Growth factor distributions of the largest particles characterized typically contained a nonhygroscopic mode believed to be composed primarily of dust. A model was developed to characterize the hygroscopic properties of particles within a size distribution mode through analysis of the fixed size hygroscopic growth measurements. The performance of this model was quantified through comparison of the measured fixed size hygroscopic growth factor distributions with those simulated through convolution of the size-resolved concentration contributed by each of the size modes and the mode-resolved hygroscopicity. This transformation from sizeresolved hygroscopicity to mode-resolved hygroscopicity facilitated examination of changes in the hygroscopic properties of particles within a size distribution mode that accompanied changes in the sizes of those particles. This model was used to examine three specific cases in which the sampled aerosol evolved slowly over a period of hours or days.

Experimental performance of a 13.65-centimeter-tip-diameter tandem-bladed sweptback centrifugal compressor designed for a pressure ratio of 6

NASA Technical Reports Server (NTRS)

Klassen, H. A.; Wood, J. R.; Schumann, L. F.

1977-01-01

A 13.65 cm tip diameter backswept centrifugal impeller having a tandem inducer and a design mass flow rate of 0.907 kg/sec was experimentally investigated to establish stage and impeller characteristics. Tests were conducted with both a cascade diffuser and a vaneless diffuser. A pressure ratio of 5.9 was obtained near surge for the smallest clearance tested. Flow range at design speed was 6.3 percent for the smallest clearance test. Impeller exit to shroud axial clearance at design speed was varied to determine the effect on stage and impeller performance.

The ultimate picture-the combination of live cell superresolution microscopy and single molecule tracking yields highest spatio-temporal resolution.

PubMed

Dersch, Simon; Graumann, Peter L

2018-06-01

We are witnessing a breathtaking development in light (fluorescence) microscopy, where structures can be resolved down to the size of a ribosome within cells. This has already yielded surprising insight into the subcellular structure of cells, including the smallest cells, bacteria. Moreover, it has become possible to visualize and track single fluorescent protein fusions in real time, and quantify molecule numbers within individual cells. Combined, super resolution and single molecule tracking are pushing the limits of our understanding of the spatio-temporal organization even of the smallest cells to an unprecedented depth. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hierarchical formation of dark matter halos and the free streaming scale

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

Ishiyama, Tomoaki, E-mail: ishiyama@ccs.tsukuba.ac.jp

2014-06-10

The smallest dark matter halos are formed first in the early universe. According to recent studies, the central density cusp is much steeper in these halos than in larger halos and scales as ρ∝r {sup –(1.5-1.3)}. We present the results of very large cosmological N-body simulations of the hierarchical formation and evolution of halos over a wide mass range, beginning from the formation of the smallest halos. We confirmed early studies that the inner density cusps are steeper in halos at the free streaming scale. The cusp slope gradually becomes shallower as the halo mass increases. The slope of halosmore » 50 times more massive than the smallest halo is approximately –1.3. No strong correlation exists between the inner slope and the collapse epoch. The cusp slope of halos above the free streaming scale seems to be reduced primarily due to major merger processes. The concentration, estimated at the present universe, is predicted to be 60-70, consistent with theoretical models and earlier simulations, and ruling out simple power law mass-concentration relations. Microhalos could still exist in the present universe with the same steep density profiles.« less

Observation and characterization of the smallest borospherene, B{sub 28}{sup −} and B{sub 28}

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

Wang, Ying-Jin; Chen, Qiang; You, Xue-Rui

2016-02-14

Free-standing boron nanocages or borospherenes have been observed recently for B{sub 40}{sup −} and B{sub 40}. There is evidence that a family of borospherenes may exist. However, the smallest borospherene is still not known. Here, we report experimental and computational evidence of a seashell-like borospherene cage for B{sub 28}{sup −} and B{sub 28}. Photoelectron spectrum of B{sub 28}{sup −} indicated contributions from different isomers. Theoretical calculations showed that the seashell-like B{sub 28}{sup −} borospherene is competing for the global minimum with a planar isomer and it is shown to be present in the cluster beam, contributing to the observed photoelectronmore » spectrum. The seashell structure is found to be the global minimum for neutral B{sub 28} and the B{sub 28}{sup −} cage represents the smallest borospherene observed to date. It is composed of two triangular close-packed B{sub 15} sheets, interconnected via the three corners by sharing two boron atoms. The B{sub 28} borospherene was found to obey the 2(n + 1){sup 2} electron-counting rule for spherical aromaticity.« less

A review of the automated detection and classification of acute leukaemia: Coherent taxonomy, datasets, validation and performance measurements, motivation, open challenges and recommendations.

PubMed

Alsalem, M A; Zaidan, A A; Zaidan, B B; Hashim, M; Madhloom, H T; Azeez, N D; Alsyisuf, S

2018-05-01

Acute leukaemia diagnosis is a field requiring automated solutions, tools and methods and the ability to facilitate early detection and even prediction. Many studies have focused on the automatic detection and classification of acute leukaemia and their subtypes to promote enable highly accurate diagnosis. This study aimed to review and analyse literature related to the detection and classification of acute leukaemia. The factors that were considered to improve understanding on the field's various contextual aspects in published studies and characteristics were motivation, open challenges that confronted researchers and recommendations presented to researchers to enhance this vital research area. We systematically searched all articles about the classification and detection of acute leukaemia, as well as their evaluation and benchmarking, in three main databases: ScienceDirect, Web of Science and IEEE Xplore from 2007 to 2017. These indices were considered to be sufficiently extensive to encompass our field of literature. Based on our inclusion and exclusion criteria, 89 articles were selected. Most studies (58/89) focused on the methods or algorithms of acute leukaemia classification, a number of papers (22/89) covered the developed systems for the detection or diagnosis of acute leukaemia and few papers (5/89) presented evaluation and comparative studies. The smallest portion (4/89) of articles comprised reviews and surveys. Acute leukaemia diagnosis, which is a field requiring automated solutions, tools and methods, entails the ability to facilitate early detection or even prediction. Many studies have been performed on the automatic detection and classification of acute leukaemia and their subtypes to promote accurate diagnosis. Research areas on medical-image classification vary, but they are all equally vital. We expect this systematic review to help emphasise current research opportunities and thus extend and create additional research fields. Copyright © 2018 Elsevier B.V. All rights reserved.

Radio and optical observations of 0218+357 - The smallest Einstein ring?

NASA Technical Reports Server (NTRS)

O'Dea, Christopher P.; Baum, Stefi A.; Stanghellini, Carlo; Dey, Arjun; Van Breugel, Wil; Deustua, Susana; Smith, Eric P.

1992-01-01

VLA radio observations and optical imaging and spectroscopy of the Einstein radio ring 0218+357 are presented. The ring is detected at 22.4 GHz and shows a basically similar structure at 5, 15, and 22.4 GHz. The B component has varied and was about 15 percent brighter in the 8.4 GHz data than in the data of Patnaik et al. (1992). The ring is highly polarized. A weak jetlike feature extending out roughly 2 arcsec to the southeast of component A is detected at 6 cm. The source has amorphous radio structure extending out to about 11 arcsec from the core. For an adopted redshift of 0.68, the extended radio emission is very powerful. The optical spectrum is rather red and shows no strong features. A redshift of about 0.68 is obtained. The identification is a faint compact m(r) about 20 galaxy which extends to about 4.5 arcsec (about 27 kpc). As much as 50 percent of the total light may be due to a central AGN. The observed double core and ring may be produced by an off-center radio core with extended radio structure.

Search for correlations between the arrival directions of IceCube neutrino events and ultrahigh-energy cosmic rays detected by the Pierre Auger Observatory and the Telescope Array

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

IceCube Collaboration; Pierre Auger Collaboration; Telescope Array Collaboration

2016-01-01

This paper presents the results of different searches for correlations between very high-energy neutrino candidates detected by IceCube and the highest-energy cosmic rays measured by the Pierre Auger Observatory and the Telescope Array. We first consider samples of cascade neutrino events and of high-energy neutrino-induced muon tracks, which provided evidence for a neutrino flux of astrophysical origin, and study their cross-correlation with the ultrahigh-energy cosmic ray (UHECR) samples as a function of angular separation. We also study their possible directional correlations using a likelihood method stacking the neutrino arrival directions and adopting different assumptions on the size of the UHECRmore » magnetic deflections. Finally, we perform another likelihood analysis stacking the UHECR directions and using a sample of through-going muon tracks optimized for neutrino point-source searches with sub-degree angular resolution. No indications of correlations at discovery level are obtained for any of the searches performed. The smallest of the p-values comes from the search for correlation between UHECRs with IceCube high-energy cascades, a result that should continue to be monitored.« less

Modeling Emission of Heavy Energetic Neutral Atoms from the Heliosphere

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

Swaczyna, Paweł; Bzowski, Maciej, E-mail: pswaczyna@cbk.waw.pl

2017-09-10

Observations of energetic neutral atoms (ENAs) are a fruitful tool for remote diagnosis of the plasma in the heliosphere and its vicinity. So far, instruments detecting ENAs from the heliosphere were configured for observations of hydrogen atoms. Here, we estimate emissions of ENAs of the heavy chemical elements helium, oxygen, nitrogen, and neon. A large portion of the heliospheric ENAs is created in the inner heliosheath from neutralized interstellar pick-up ions (PUIs). We modeled this process and calculated full-sky intensities of ENAs for energies 0.2–130 keV/nuc. We found that the largest fluxes among considered species are expected for helium, smallermore » for oxygen and nitrogen, and smallest for neon. The obtained intensities are 50–10{sup 6} times smaller than the hydrogen ENA intensities observed by IBEX . The detection of heavy ENAs will be possible if a future ENA detector is equipped with the capability to measure the masses of observed atoms. Because of different reaction cross-sections among the different species, observations of heavy ENAs can allow for a better understanding of global structure of the heliosphere as well as the transport and energization of PUIs in the heliosphere.« less

Two-level bulk microfabrication of a mechanical broadband vibration amplitude-amplifier with ten coupled resonators

NASA Astrophysics Data System (ADS)

Müller, Michelle; Maiwald, Verena; Thiele, Lothar; Beutel, Jan; Roman, Cosmin; Hierold, Christofer

2018-04-01

A micromechanical broadband vibration amplitude-amplifier for low power detection of acoustic emission signals is presented. It is based on a coupled mass-spring system and was fabricated in a two-level bulk microfabrication process. The device consists of ten resonators coupled in series, which decrease in mass by a factor of three each, to achieve a high amplification over a broad bandwidth. The fabrication process for this multiscale device is based on front- and backside etching of a silicon-on-insulator wafer. It enables coupling MEMS resonators of two different thicknesses with a weight ratio from largest to smallest mass of 26’244 and reduces die size by resonator stacking. The first ten eigenmodes of the device are in-plane and unidirectional. Steady-state and transient response of the device in comparison to a 1D lumped element model is presented. An average amplitude amplification of 295 over a bandwidth of 10.7 kHz (4.4-15.1 kHz) is achieved and can be reached in less than 1 ms. Applications are low-power detection of short broadband vibration signals e.g. for structural health monitoring (cliffs, pipelines, bridges).

Nationwide Genomic Study in Denmark Reveals Remarkable Population Homogeneity

PubMed Central

Athanasiadis, Georgios; Cheng, Jade Y.; Vilhjálmsson, Bjarni J.; Jørgensen, Frank G.; Als, Thomas D.; Le Hellard, Stephanie; Espeseth, Thomas; Sullivan, Patrick F.; Hultman, Christina M.; Kjærgaard, Peter C.; Schierup, Mikkel H.; Mailund, Thomas

2016-01-01

Denmark has played a substantial role in the history of Northern Europe. Through a nationwide scientific outreach initiative, we collected genetic and anthropometrical data from ∼800 high school students and used them to elucidate the genetic makeup of the Danish population, as well as to assess polygenic predictions of phenotypic traits in adolescents. We observed remarkable homogeneity across different geographic regions, although we could still detect weak signals of genetic structure reflecting the history of the country. Denmark presented genomic affinity with primarily neighboring countries with overall resemblance of decreasing weight from Britain, Sweden, Norway, Germany, and France. A Polish admixture signal was detected in Zealand and Funen, and our date estimates coincided with historical evidence of Wend settlements in the south of Denmark. We also observed considerably diverse demographic histories among Scandinavian countries, with Denmark having the smallest current effective population size compared to Norway and Sweden. Finally, we found that polygenic prediction of self-reported adolescent height in the population was remarkably accurate (R2 = 0.639 ± 0.015). The high homogeneity of the Danish population could render population structure a lesser concern for the upcoming large-scale gene-mapping studies in the country. PMID:27535931

Search for correlations between the arrival directions of IceCube neutrino events and ultrahigh-energy cosmic rays detected by the Pierre Auger Observatory and the Telescope Array

DOE PAGES

Aartsen, M. G.

2016-01-20

This study presents the results of different searches for correlations between very high-energy neutrino candidates detected by IceCube and the highest-energy cosmic rays measured by the Pierre Auger Observatory and the Telescope Array. We first consider samples of cascade neutrino events and of high-energy neutrino-induced muon tracks, which provided evidence for a neutrino flux of astrophysical origin, and study their cross-correlation with the ultrahigh-energy cosmic ray (UHECR) samples as a function of angular separation. We also study their possible directional correlations using a likelihood method stacking the neutrino arrival directions and adopting different assumptions on the size of the UHECRmore » magnetic deflections. Finally, we perform another likelihood analysis stacking the UHECR directions and using a sample of through-going muon tracks optimized for neutrino point-source searches with sub-degree angular resolution. No indications of correlations at discovery level are obtained for any of the searches performed. The smallest of the p-values comes from the search for correlation between UHECRs with IceCube high-energy cascades, a result that should continue to be monitored.« less

Dual-Emission SG7@MOF Sensor via SC-SC Transformation: Enhancing the Formation of Excimer Emission and the Range and Sensitivity of Detection.

PubMed

Fu, Hong-Ru; Wu, Xiao-Xia; Ma, Lu-Fang; Wang, Fei; Zhang, Jian

2018-05-30

In this study, a water stable metal-organic framework FIR-53 is applied as a single-crystal container for anion exchange. The exceptional chemical stability and low crystallographic symmetry of FIR-53 makes it possible to determine anionic guests. Through ion exchange and single-crystal to single-crystal (SC-SC) transformation, 8-hydroxypyrene-1,3,6-trisulfonate (SG7, solvent green 7, ion form as SG7 3- ) is introduced into the pores of FIR-53 to obtain SG7@FIR-53. Because of the spatial confinement and partition effect, SG7@FIR-53 shows the bright exciter emission of SG7 ions. Interestingly, the composite SG7@FIR-53 exhibits a sensitive fluorescence quenching response against Cr 2 O 7 2- and MnO 4 - in aqueous solution. Especially, the detection limit toward MnO 4 - is as low as 0.12 ppb, which is the smallest value to date. Moreover, the prepared SG7@FIR-53 film also displays a broad response to nitro explosives in vapor/aqueous phase. Compared with the results of FIR-53, the range and sensitivity were greatly improved.

Liver tumor boundaries identified intraoperatively using real-time indocyanine green fluorescence imaging.

PubMed

Zhang, Ya-Min; Shi, Rui; Hou, Jian-Cun; Liu, Zi-Rong; Cui, Zi-Lin; Li, Yang; Wu, Di; Shi, Yuan; Shen, Zhong-Yang

2017-01-01

Clear delineation between tumors and normal tissues is ideal for real-time surgical navigation imaging. We investigated applying indocyanine green (ICG) fluorescence imaging navigation using an intraoperative administration method in liver resection. Fifty patients who underwent liver resection were divided into two groups based on clinical situation and operative purpose. In group I, sizes of superficial liver tumors were determined; tiny tumors were identified. In group II, the liver resection margin was determined; real-time navigation was performed. ICG was injected intravenously at the beginning of the operation; the liver surface was observed with a photodynamic eye (PDE). Liver resection margins were determined using PDE. Fluorescence contrast between normal liver and tumor tissues was obvious in 32 of 35 patients. A boundary for half the liver or specific liver segments was determined in nine patients by examining the portal vein anatomy after ICG injection. Eight small tumors not observed preoperatively were detected; the smallest was 2 mm. ICG fluorescence imaging navigation is a promising, simple, and safe tool for routine real-time intraoperative imaging during hepatic resection and clinical exploration in hepatocellular carcinoma, enabling high sensibility for identifying liver resection margins and detecting tiny superficial tumors.

Mismatch cleavage by single-strand specific nucleases

PubMed Central

Till, Bradley J.; Burtner, Chris; Comai, Luca; Henikoff, Steven

2004-01-01

We have investigated the ability of single-strand specific (sss) nucleases from different sources to cleave single base pair mismatches in heteroduplex DNA templates used for mutation and single-nucleotide polymorphism analysis. The TILLING (Targeting Induced Local Lesions IN Genomes) mismatch cleavage protocol was used with the LI-COR gel detection system to assay cleavage of amplified heteroduplexes derived from a variety of induced mutations and naturally occurring polymorphisms. We found that purified nucleases derived from celery (CEL I), mung bean sprouts and Aspergillus (S1) were able to specifically cleave nearly all single base pair mismatches tested. Optimal nicking of heteroduplexes for mismatch detection was achieved using higher pH, temperature and divalent cation conditions than are routinely used for digestion of single-stranded DNA. Surprisingly, crude plant extracts performed as well as the highly purified preparations for this application. These observations suggest that diverse members of the S1 family of sss nucleases act similarly in cleaving non-specifically at bulges in heteroduplexes, and single-base mismatches are the least accessible because they present the smallest single-stranded region for enzyme binding. We conclude that a variety of sss nucleases and extracts can be effectively used for high-throughput mutation and polymorphism discovery. PMID:15141034

Proactive and Reactive Stopping When Distracted: An Attentional Account

PubMed Central

2014-01-01

Performance in response inhibition paradigms is typically attributed to inhibitory control. Here we examined the idea that stopping may largely depend on the outcome of a sensory detection process. Subjects performed a speeded go task, but they were instructed to withhold their response when a visual stop signal was presented. The stop signal could occur in the center of the screen or in the periphery. On half of the trials, perceptual distractors were presented throughout the trial. We found that these perceptual distractors impaired stopping, especially when stop signals could occur in the periphery. Furthermore, the effect of the distractors on going was smallest in the central stop-signal condition, medium in a condition in which no signals could occur, and largest in the condition in which stop signals could occur in the periphery. The results show that an important component of stopping is finding a balance between ignoring irrelevant information in the environment and monitoring for the occurrence of occasional stop signals. These findings highlight the importance of sensory detection processes when stopping and could shed new light on a range of phenomena and findings in the response inhibition literature. PMID:24842070

Characterizing a Wake-Free Safe Zone for the Simplified Aircraft-Based Paired Approach Concept

NASA Technical Reports Server (NTRS)

Guerreiro, Nelson M.; Neitzke, Kurt W.; Johnson, Sally C.; Stough, H. Paul, III; McKissick, Burnell T.; Syed, Hazari I.

2010-01-01

The Federal Aviation Administration (FAA) has proposed a concept of operations geared towards achieving increased arrival throughput at U.S. Airports, known as the Simplified Aircraft-based Paired Approach (SAPA) concept. In this study, a preliminary characterization of a wake-free safe zone (WFSZ) for the SAPA concept has been performed. The experiment employed Monte-Carlo simulations of varying approach profiles by aircraft pairs to closely-spaced parallel runways. Three different runway lateral spacings were investigated (750 ft, 1000 ft and 1400 ft), along with no stagger and 1500 ft stagger between runway thresholds. The paired aircraft were flown in a leader/trailer configuration with potential wake encounters detected using a wake detection surface translating with the trailing aircraft. The WFSZ is characterized in terms of the smallest observed initial in-trail distance leading to a wake encounter anywhere along the approach path of the aircraft. The results suggest that the WFSZ can be characterized in terms of two primary altitude regions, in ground-effect (IGE) and out of ground-effect (OGE), with the IGE region being the limiting case with a significantly smaller WFSZ. Runway stagger was observed to only modestly reduce the WFSZ size, predominantly in the OGE region.

Modeling Emission of Heavy Energetic Neutral Atoms from the Heliosphere

NASA Astrophysics Data System (ADS)

Swaczyna, Paweł; Bzowski, Maciej

2017-09-01

Observations of energetic neutral atoms (ENAs) are a fruitful tool for remote diagnosis of the plasma in the heliosphere and its vicinity. So far, instruments detecting ENAs from the heliosphere were configured for observations of hydrogen atoms. Here, we estimate emissions of ENAs of the heavy chemical elements helium, oxygen, nitrogen, and neon. A large portion of the heliospheric ENAs is created in the inner heliosheath from neutralized interstellar pick-up ions (PUIs). We modeled this process and calculated full-sky intensities of ENAs for energies 0.2-130 keV/nuc. We found that the largest fluxes among considered species are expected for helium, smaller for oxygen and nitrogen, and smallest for neon. The obtained intensities are 50-106 times smaller than the hydrogen ENA intensities observed by IBEX. The detection of heavy ENAs will be possible if a future ENA detector is equipped with the capability to measure the masses of observed atoms. Because of different reaction cross-sections among the different species, observations of heavy ENAs can allow for a better understanding of global structure of the heliosphere as well as the transport and energization of PUIs in the heliosphere.

Estimating unbiased magnitudes for the announced DPRK nuclear tests, 2006-2016

NASA Astrophysics Data System (ADS)

Peacock, Sheila; Bowers, David

2017-04-01

The seismic disturbances generated from the five (2006-2016) announced nuclear test explosions by the Democratic People's Republic of Korea (DPRK) are of moderate magnitude (body-wave magnitude mb 4-5) by global earthquake standards. An upward bias of network mean mb of low- to moderate-magnitude events is long established, and is caused by the censoring of readings from stations where the signal was below noise level at the time of the predicted arrival. This sampling bias can be overcome by maximum-likelihood methods using station thresholds at detecting (and non-detecting) stations. Bias in the mean mb can also be introduced by differences in the network of stations recording each explosion - this bias can reduced by using station corrections. We apply a maximum-likelihood (JML) inversion that jointly estimates station corrections and unbiased network mb for the five DPRK explosions recorded by the CTBTO International Monitoring Network (IMS) of seismic stations. The thresholds can either be directly measured from the noise preceding the observed signal, or determined by statistical analysis of bulletin amplitudes. The network mb of the first and smallest explosion is reduced significantly relative to the mean mb (to < 4.0 mb) by removal of the censoring bias.

Combining nanofluidics and plasmonics for single molecule detection

NASA Astrophysics Data System (ADS)

West, Melanie M.

Single molecule detection is limited by the small scattering cross-section of molecules which leads to weak optical signals that can be obscured by background noise. The combination of plasmonics and nanofluidics in an integrated nano-device has the potential to provide the signal enhancement necessary for the detection of single molecules. The purpose of this investigation was to optimize the fabrication of an optofluidic device that integrates a nanochannel with a plasmonic bowtie antenna. The fluidic structure of the device was fabricated using UV-nanoimprint lithography, and the gold plasmonic antennas were fabricated using a shadow evaporation and lift-off process. The effect of electron beam lithography doses on the resolution of antenna-nanochannel configurations was studied to minimize antenna gap size while maintaining the integrity of the imprinted features. The smallest antenna gap size that was achieved was 46 nm. The antennas were characterized using dark field spectroscopy to find the resonance shift, which indicated the appropriate range for optical signal enhancement. The dark field scattering results showed antennas with a broad and well-defined resonance shift that ranged from 650--800 nm. The Raman scattering results showed the highest enhancement factor (EF = 2) for antennas with an "inverted configuration," which involved having the triangles of the antenna facing back-to-back rather than the more conventional tip-to-tip bowtie arrangement.

Small negative cloud-to-ground lightning reports at the NASA Kennedy Space Center and Air Force Eastern Range

NASA Astrophysics Data System (ADS)

Wilson, Jennifer G.; Cummins, Kenneth L.; Krider, E. Philip

2009-12-01

The NASA Kennedy Space Center (KSC) and Air Force Eastern Range (ER) use data from two cloud-to-ground (CG) lightning detection networks, the Cloud-to-Ground Lightning Surveillance System (CGLSS) and the U.S. National Lightning Detection Network™ (NLDN), and a volumetric lightning mapping array, the Lightning Detection and Ranging (LDAR) system, to monitor and characterize lightning that is potentially hazardous to launch or ground operations. Data obtained from these systems during June-August 2006 have been examined to check the classification of small, negative CGLSS reports that have an estimated peak current, ∣Ip∣ less than 7 kA, and to determine the smallest values of Ip that are produced by first strokes, by subsequent strokes that create a new ground contact (NGC), and by subsequent strokes that remain in a preexisting channel (PEC). The results show that within 20 km of the KSC-ER, 21% of the low-amplitude negative CGLSS reports were produced by first strokes, with a minimum Ip of -2.9 kA; 31% were by NGCs, with a minimum Ip of -2.0 kA; and 14% were by PECs, with a minimum Ip of -2.2 kA. The remaining 34% were produced by cloud pulses or lightning events that we were not able to classify.

Validation of the CrIS fast physical NH3 retrieval with ground-based FTIR

NASA Astrophysics Data System (ADS)

Dammers, Enrico; Shephard, Mark W.; Palm, Mathias; Cady-Pereira, Karen; Capps, Shannon; Lutsch, Erik; Strong, Kim; Hannigan, James W.; Ortega, Ivan; Toon, Geoffrey C.; Stremme, Wolfgang; Grutter, Michel; Jones, Nicholas; Smale, Dan; Siemons, Jacob; Hrpcek, Kevin; Tremblay, Denis; Schaap, Martijn; Notholt, Justus; Erisman, Jan Willem

2017-07-01

Presented here is the validation of the CrIS (Cross-track Infrared Sounder) fast physical NH3 retrieval (CFPR) column and profile measurements using ground-based Fourier transform infrared (FTIR) observations. We use the total columns and profiles from seven FTIR sites in the Network for the Detection of Atmospheric Composition Change (NDACC) to validate the satellite data products. The overall FTIR and CrIS total columns have a positive correlation of r = 0.77 (N = 218) with very little bias (a slope of 1.02). Binning the comparisons by total column amounts, for concentrations larger than 1.0 × 1016 molecules cm-2, i.e. ranging from moderate to polluted conditions, the relative difference is on average ˜ 0-5 % with a standard deviation of 25-50 %, which is comparable to the estimated retrieval uncertainties in both CrIS and the FTIR. For the smallest total column range (< 1.0 × 1016 molecules cm-2) where there are a large number of observations at or near the CrIS noise level (detection limit) the absolute differences between CrIS and the FTIR total columns show a slight positive column bias. The CrIS and FTIR profile comparison differences are mostly within the range of the single-level retrieved profile values from estimated retrieval uncertainties, showing average differences in the range of ˜ 20 to 40 %. The CrIS retrievals typically show good vertical sensitivity down into the boundary layer which typically peaks at ˜ 850 hPa (˜ 1.5 km). At this level the median absolute difference is 0.87 (std = ±0.08) ppb, corresponding to a median relative difference of 39 % (std = ±2 %). Most of the absolute and relative profile comparison differences are in the range of the estimated retrieval uncertainties. At the surface, where CrIS typically has lower sensitivity, it tends to overestimate in low-concentration conditions and underestimate in higher atmospheric concentration conditions.

A novel Alu-mediated microdeletion at 11p13 removes WT1 in a patient with cryptorchidism and azoospermia.

PubMed

Seabra, Catarina M; Quental, Sofia; Neto, Ana Paula; Carvalho, Filipa; Gonçalves, João; Oliveira, João Paulo; Fernandes, Susana; Sousa, Mário; Barros, Alberto; Amorim, António; Lopes, Alexandra M

2014-09-01

This article describes a patient with cryptorchidism and nonobstructive azoospermia presenting a novel microdeletion of approximately 1 Mb at 11p13. It was confirmed by multiplex ligation-dependent probe amplification that this heterozygous deletion spanned nine genes (WT1, EIF3M, CCDC73, PRRG4, QSER1, DEPDC7, TCP11L1, CSTF3 and HIPK3) and positioned the breakpoints within highly homologous repetitive elements. As far as is known, this is the smallest deletion as-yet described encompassing the WT1 gene and was detected only once in a total of 32 Portuguese patients with isolated uni- or bilateral cryptorchidism. These findings suggest that molecular analysis in patients with genitourinary features suggestive of WT1 impairment, namely cryptorchidism and renal abnormalities, may reveal cryptic genetic defects. Copyright © 2014 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.

In vivo fluorescence imaging of primate retinal ganglion cells and retinal pigment epithelial cells

NASA Astrophysics Data System (ADS)

Gray, Daniel C.; Merigan, William; Wolfing, Jessica I.; Gee, Bernard P.; Porter, Jason; Dubra, Alfredo; Twietmeyer, Ted H.; Ahamd, Kamran; Tumbar, Remy; Reinholz, Fred; Williams, David R.

2006-08-01

The ability to resolve single cells noninvasively in the living retina has important applications for the study of normal retina, diseased retina, and the efficacy of therapies for retinal disease. We describe a new instrument for high-resolution, in vivo imaging of the mammalian retina that combines the benefits of confocal detection, adaptive optics, multispectral, and fluorescence imaging. The instrument is capable of imaging single ganglion cells and their axons through retrograde transport in ganglion cells of fluorescent dyes injected into the monkey lateral geniculate nucleus (LGN). In addition, we demonstrate a method involving simultaneous imaging in two spectral bands that allows the integration of very weak signals across many frames despite inter-frame movement of the eye. With this method, we are also able to resolve the smallest retinal capillaries in fluorescein angiography and the mosaic of retinal pigment epithelium (RPE) cells with lipofuscin autofluorescence.

Research highlights: impacts of microplastics on plankton.

PubMed

Lin, Vivian S

2016-02-01

Each year, millions of metric tons of the plastic produced for food packaging, personal care products, fishing gear, and other human activities end up in lakes, rivers, and the ocean. The breakdown of these primary plastics in the environment results in microplastics, small fragments of plastic typically less than 1-5 mm in size. These synthetic particles have been detected in all of the world's oceans and also in many freshwater systems, accumulating in sediment, on shorelines, suspended in surface waters, and being ingested by plankton, fish, birds, and marine mammals. While the occurrence of plastics in surface waters has been surveyed in a number of studies, the impacts of microplastics on marine organisms are still being elucidated. This highlight features three recent publications that explore the interactions of microplastics with planktonic organisms to clarify the effects of these pollutants on some of the ocean's smallest and most important inhabitants.

Three faces of node importance in network epidemiology: Exact results for small graphs

NASA Astrophysics Data System (ADS)

Holme, Petter

2017-12-01

We investigate three aspects of the importance of nodes with respect to susceptible-infectious-removed (SIR) disease dynamics: influence maximization (the expected outbreak size given a set of seed nodes), the effect of vaccination (how much deleting nodes would reduce the expected outbreak size), and sentinel surveillance (how early an outbreak could be detected with sensors at a set of nodes). We calculate the exact expressions of these quantities, as functions of the SIR parameters, for all connected graphs of three to seven nodes. We obtain the smallest graphs where the optimal node sets are not overlapping. We find that (i) node separation is more important than centrality for more than one active node, (ii) vaccination and influence maximization are the most different aspects of importance, and (iii) the three aspects are more similar when the infection rate is low.

New Understanding of Mercury's Magnetosphere from MESSENGER'S First Flyby

NASA Technical Reports Server (NTRS)

Slavin, James A.; Acuna, Mario H.; Anderson, Brian J.; Baker, Daniel N.; Benna, Mehdi; Gloeckler, George; Gold, Robert E.; Ho, George C.; Killen, M.; Korth, Haje;

Complete denture base assessments using holograms: dimensional alterations after different activation methods

NASA Astrophysics Data System (ADS)

Dughir, Ciprian; Popovschi, Ana Maria; Cojocariu, Andreea Codruta; Topala, Florin Ionel; Negrutiu, Meda Lavinia; Sinescu, Cosmin; de Sabata, Aldo; Duma, Virgil-Florin

2016-03-01

Holography is a well-developed method with a large range of applications, including dentistry. This study uses holographic methods for the study of total dental prosthesis. The issue is that the transformation of wax denture base in polymethylacrylate causes dimensional alterations and retractions in the final dental constructs. These could cause the failure of the stability of the complete denture in the oral cavity. Thus, the aim of this study is to determine and to compare using holography, total prosthesis obtained using three different manufacturing methods: pressing, injection, and polymerization. Each of the three types of dentures thus produced were recorded over the previously wax complete base holographic plates. The dimensional alterations that appear after using the different activation methods were thus determined. The most significant modification was remarked in the custom press technology, while the smallest variations were detected in the injection alternative.

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

Winn, Joshua N.; Albrecht, Simon; Johnson, John Asher

We find the orbit of the Neptune-sized exoplanet HAT-P-11b to be highly inclined relative to the equatorial plane of its host star. This conclusion is based on spectroscopic observations of two transits, which allowed the Rossiter-McLaughlin effect to be detected with an amplitude of 1.5 m s{sup -1}. The sky-projected obliquity is 103{sup +26} {sub -10} deg. This is the smallest exoplanet for which spin-orbit alignment has been measured. The result favors a migration scenario involving few-body interactions followed by tidal dissipation. This finding also conforms with the pattern that the systems with the weakest tidal interactions have the widestmore » spread in obliquities. We predict that the high obliquity of HAT-P-11 will be manifest in transit light curves from the Kepler spacecraft: starspot-crossing anomalies will recur at most once per stellar rotation period, rather than once per orbital period as they would for a well-aligned system.« less

HIV-1 isolation from infected peripheral blood mononuclear cells.

PubMed

Dispinseri, Stefania; Saba, Elisa; Vicenzi, Elisa; Kootstra, Neeltje A; Schuitemaker, Hanneke; Scarlatti, Gabriella

2014-01-01

Human immunodeficiency virus 1 (HIV-1) isolation from peripheral blood mononuclear cells (PBMCs) allows retrieval of replication-competent viral variants. In order to impose the smallest possible selective pressure on the viral isolates, isolation must be carried out in primary cultures of cells and not in tumor derived cell lines. The procedure involves culture of PBMCs from an infected patient with phytohemagglutinin (PHA)-stimulated PBMC from seronegative donors, which provide susceptible target cells for HIV replication. HIV can be isolated from the bulk population of PBMCs or after cloning of the cells to obtain viral biological clones. Viral production is determined with p24 antigen (Ag) detection assays or with reverse transcriptase (RT) activity assay. Once isolated, HIV-1 can be propagated by infecting PHA-stimulated PBMCs from healthy donors. Aliquots from culture with a high production of virus are stored for later use.

"Click" chemistry mildly stabilizes bifunctional gold nanoparticles for sensing and catalysis.

PubMed

Li, Na; Zhao, Pengxiang; Liu, Na; Echeverria, María; Moya, Sergio; Salmon, Lionel; Ruiz, Jaime; Astruc, Didier

2014-07-01

A large family of bifunctional 1,2,3-triazole derivatives that contain both a polyethylene glycol (PEG) chain and another functional fragment (e.g., a polymer, dendron, alcohol, carboxylic acid, allyl, fluorescence dye, redox-robust metal complex, or a β-cyclodextrin unit) has been synthesized by facile "click" chemistry and mildly coordinated to nanogold particles, thus providing stable water-soluble gold nanoparticles (AuNPs) in the size range 3.0-11.2 nm with various properties and applications. In particular, the sensing properties of these AuNPs are illustrated through the detection of an analogue of a warfare agent (i.e., sulfur mustard) by means of a fluorescence "turn-on" assay, and the catalytic activity of the smallest triazole-AuNPs (core of 3.0 nm) is excellent for the reduction of 4-nitrophenol in water. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

An integrated 12.5-Gb/s optoelectronic receiver with a silicon avalanche photodetector in standard SiGe BiCMOS technology.

PubMed

Youn, Jin-Sung; Lee, Myung-Jae; Park, Kang-Yeob; Rücker, Holger; Choi, Woo-Young

2012-12-17

An optoelectronic integrated circuit (OEIC) receiver is realized with standard 0.25-μm SiGe BiCMOS technology for 850-nm optical interconnect applications. The OEIC receiver consists of a Si avalanche photodetector, a transimpedance amplifier with a DC-balanced buffer, a tunable equalizer, and a limiting amplifier. The fabricated OEIC receiver successfully detects 12.5-Gb/s 2(31)-1 pseudorandom bit sequence optical data with the bit-error rate less than 10(-12) at incident optical power of -7 dBm. The OEIC core has 1000 μm x 280 μm chip area, and consumes 59 mW from 2.5-V supply. To the best of our knowledge, this OEIC receiver achieves the highest data rate with the smallest sensitivity as well as the best power efficiency among integrated OEIC receivers fabricated with standard Si technology.

Statistical significance of combinatorial regulations

PubMed Central

Terada, Aika; Okada-Hatakeyama, Mariko; Tsuda, Koji; Sese, Jun

2013-01-01

More than three transcription factors often work together to enable cells to respond to various signals. The detection of combinatorial regulation by multiple transcription factors, however, is not only computationally nontrivial but also extremely unlikely because of multiple testing correction. The exponential growth in the number of tests forces us to set a strict limit on the maximum arity. Here, we propose an efficient branch-and-bound algorithm called the “limitless arity multiple-testing procedure” (LAMP) to count the exact number of testable combinations and calibrate the Bonferroni factor to the smallest possible value. LAMP lists significant combinations without any limit, whereas the family-wise error rate is rigorously controlled under the threshold. In the human breast cancer transcriptome, LAMP discovered statistically significant combinations of as many as eight binding motifs. This method may contribute to uncover pathways regulated in a coordinated fashion and find hidden associations in heterogeneous data. PMID:23882073

Broadband Microwave Study of Reaction Intermediates and Products Through the Pyrolysis of Oxygenated Biofuels

NASA Astrophysics Data System (ADS)

Abeysekera, Chamara; Hernandez-Castillo, Alicia O.; Fritz, Sean; Zwier, Timothy S.

2017-06-01

The rapidly growing list of potential plant-derived biofuels creates a challenge for the scientific community to provide a molecular-scale understanding of their combustion. Development of accurate combustion models rests on a foundation of experimental data on the kinetics and product branching ratios of their individual reaction steps. Therefore, new spectroscopic tools are necessary to selectively detect and characterize fuel components and reactive intermediates generated by pyrolysis and combustion. Substituted furans, including furanic ethers, are considered second-generation biofuel candidates. Following the work of the Ellison group, an 8-18 GHz microwave study was carried out on the unimolecular and bimolecular decomposition of the smallest furanic ether, 2-methoxy furan, and it`s pyrolysis intermediate, the 2-furanyloxy radical, formed in a high-temperature pyrolysis source coupled to a supersonic expansion. Details of the experimental setup and analysis of the spectrum of the radical will be discussed.

Nanosecond radio bursts from strong plasma turbulence in the Crab pulsar.

PubMed

Hankins, T H; Kern, J S; Weatherall, J C; Eilek, J A

2003-03-13

The Crab pulsar was discovered by the occasional exceptionally bright radio pulses it emits, subsequently dubbed 'giant' pulses. Only two other pulsars are known to emit giant pulses. There is no satisfactory explanation for the occurrence of giant pulses, nor is there a complete theory of the pulsar emission mechanism in general. Competing models for the radio emission mechanism can be distinguished by the temporal structure of their coherent emission. Here we report the discovery of isolated, highly polarized, two-nanosecond subpulses within the giant radio pulses from the Crab pulsar. The plasma structures responsible for these emissions must be smaller than one metre in size, making them by far the smallest objects ever detected and resolved outside the Solar System, and the brightest transient radio sources in the sky. Only one of the current models--the collapse of plasma-turbulent wave packets in the pulsar magnetosphere--can account for the nanopulses we observe.

Characterization of ions at Alpine waterfalls

NASA Astrophysics Data System (ADS)

Kolarž, P.; Gaisberger, M.; Madl, P.; Hofmann, W.; Ritter, M.; Hartl, A.

2012-04-01

During a three-year field campaign of measuring waterfall generated ions, we monitored five different waterfalls in the Austrian Alps. Most measurements were performed at the Krimml waterfall (Salzburg, Austria), which is the biggest waterfall in Europe, and the Gartl waterfall (Mölltal, Austria). We characterized spatial, time and size distributions of waterfall-generated ions under the influence of surrounding topography. The smallest ions with boundary diameters of 0.9, 1.5 and 2 nm, were measured with a cylindrical air ion detector (CDI-06), while ion sizes from 5.5 to 350 nm were measured using a modified Grimm SMPS aerosol spectrometer. High negative ion concentration gradients are detected in the vicinity of the waterfalls, whereas the increase of positive ions was only moderate. Ions in the nano range were the most abundant at 2 nm, and at 120 nm in the sub-micrometer range.

Female reproductive traits of a commercially exploited skate: Atlantoraja platana (Günther, 1880) (Chondrichthyes, Rajidae). Ovarian morphology, gametogenesis and microscopic verification of maturity criteria.

PubMed

Moya, A C; Wehitt, A; Díaz Andrade, M C; Di Giacomo, E E; Galíndez, E J

2017-10-01

Atlantoraja platana is an endemic species of the Southwest Atlantic Ocean, and is one of the most captured by the local bottom trawl industrial fisheries. In this work, the microscopic architecture of mature female's gonads and the dynamics of follicle development are studied as a contribution to raise awareness of reproductive biology of the species. Folliculogenesis depicts the same histologic pattern as in other Elasmobranchs. Follicles in different degrees of maturation coexist in mature animals. The oogonia were only found in immature individuals. Likewise, atretic follicles were recorded in ovaries of all sexual maturity stages. The microscopic size recorded from the beginning of yolk input is smallest than the detected with the necked eye. This study provides valuable information about female's gametogenesis that could be taken into account in the development of fisheries management. Copyright © 2017 Elsevier Ltd. All rights reserved.

Three causes of variation in the photochemical reflectance index (PRI) in evergreen conifers.

PubMed

Wong, Christopher Y S; Gamon, John A

2015-04-01

The photochemical reflectance index (PRI) reflects diurnal xanthophyll cycle activity and is also influenced by seasonally changing carotenoid : Chl pigment ratios. Both changing pigment pools and xanthophyll cycle activity contribute to photoprotection in evergreen conifers exposed to boreal winters, but they operate over different timescales, and their relative contribution to the PRI signal has often been unclear. To clarify these responses and their contribution to the PRI signal, leaf PRI, pigment composition, temperature and irradiance were monitored over 2 yr for two evergreen conifers (Pinus contorta and Pinus ponderosa) in a boreal climate. PRI was affected by three distinct processes operating over different timescales and exhibiting contrasting spectral responses. Over the 2 yr study period, the greatest change in PRI resulted from seasonally changing carotenoid : Chl pigment ratios, followed by a previously unreported shifting leaf albedo during periods of deep cold. Remarkably, the smallest change was attributable to the xanthophyll cycle. To properly distinguish these three effects, interpretation of PRI must consider temporal context, physiological responses to evolving environmental conditions, and spectral response. Consideration of the separate mechanisms affecting PRI over different timescales could greatly improve efforts to monitor changing photosynthetic activity using optical remote sensing. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Occurrence of trihalomethanes in the nation's ground water and drinking-water supply wells, 1985-2002

USGS Publications Warehouse

Schaap, Bryan D.; Zogorski, John S.

2006-01-01

This report describes the occurrence of trihalomethanes (THMs) in the Nation's ground water and drinking-water supply wells based on analysis of 5,642 samples of untreated ground water and source water collected or compiled during 1985-2002 by the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. THMs are a group of volatile organic compounds (VOCs) with natural and anthropogenic sources that are of interest because they are associated with acute and chronic health problems in humans. THMs occur in water primarily from chlorination and are classified as disinfection by-products. In this report, the four THMs are discussed in the order of chloroform, bromodichloromethane, dibromochloromethane, and then bromoform; this sequence corresponds to largest to smallest chlorine content and smallest to largest bromine content. Four trihalomethanes were detected in less than 20 percent of samples from studies of (1) aquifers, (2) shallow ground water in agricultural areas, (3) shallow ground water in urban areas, (4) domestic wells, and (5) public wells. Detection frequencies for individual THMs in the five studies ranged from zero for shallow ground water in agricultural areas to 19.5 percent for shallow ground water in urban areas. None of the samples from aquifer studies, domestic wells, or public wells had total THM concentrations (the sum of the concentrations of chloroform, bromodichloromethane, dibromochloromethane, and bromoform) greater than or equal to the U.S. Environmental Protection Agency Maximum Contaminant Level of 80 micrograms per liter (?g/L). Comparisons of results among studies of aquifers, shallow ground water in agricultural areas, and shallow ground water in urban areas were used to describe the occurrence of the four THMs in ground water for three different land-use settings-mixed, agricultural, and urban, respectively. At the 0.2-?g/L assessment level, one or more of the four THMs were detected in 7.9 percent of the samples from aquifer studies, 2.2 percent of the samples from shallow ground water in agricultural areas, and 19.5 percent of the samples from shallow ground water in urban areas. In general, detection frequencies and concentrations of the four THMs were greater in shallow ground water in urban areas compared to aquifer studies and to shallow ground water in agricultural areas. For all three of these studies, the most common two-THM mixture at the 0.2-?g/L assessment level was chloroform-bromodichloromethane, and this was the only two-THM mixture found in samples of shallow ground water in agricultural areas. Comparisons of results between studies of domestic wells and public wells were used to describe the occurrence of the four THMs in two different supplies of ground water used for drinking water. At the 0.2-?g/L assessment level, one or more of the four THMs were detected in 5.2 percent of the domestic well samples and in 14.7 percent of the public well samples. In general, detection frequencies and THM concentrations were greater in samples from public wells than from domestic wells. At the 0.2-?g/L assessment level, the six possible two-THM mixtures occurred about six times more frequently in samples from public wells than from domestic wells. One of the most common two-THM mixtures in samples from domestic and public wells was bromodichloromethane-dibromochloromethane. Detection frequency is associated with the chlorine content of the THM compound. In general, for each of the five studies, as the chlorine content of the THM compound decreased, the detection frequency at the 0.2-?g/L assessment level also decreased. The exception was the study of public wells in which the detection frequency of the THMs decreased in the following order: chloroform, bromoform, dibromochloromethane, and bromodichloromethane. At the 0.2-?g/L assessment level, the median concentration for one or more of the four THMs ranged from 0.3 ?g/L (shallow ground water in agricultural a

Binary video codec for data reduction in wireless visual sensor networks

NASA Astrophysics Data System (ADS)

Khursheed, Khursheed; Ahmad, Naeem; Imran, Muhammad; O'Nils, Mattias

2013-02-01

Wireless Visual Sensor Networks (WVSN) is formed by deploying many Visual Sensor Nodes (VSNs) in the field. Typical applications of WVSN include environmental monitoring, health care, industrial process monitoring, stadium/airports monitoring for security reasons and many more. The energy budget in the outdoor applications of WVSN is limited to the batteries and the frequent replacement of batteries is usually not desirable. So the processing as well as the communication energy consumption of the VSN needs to be optimized in such a way that the network remains functional for longer duration. The images captured by VSN contain huge amount of data and require efficient computational resources for processing the images and wide communication bandwidth for the transmission of the results. Image processing algorithms must be designed and developed in such a way that they are computationally less complex and must provide high compression rate. For some applications of WVSN, the captured images can be segmented into bi-level images and hence bi-level image coding methods will efficiently reduce the information amount in these segmented images. But the compression rate of the bi-level image coding methods is limited by the underlined compression algorithm. Hence there is a need for designing other intelligent and efficient algorithms which are computationally less complex and provide better compression rate than that of bi-level image coding methods. Change coding is one such algorithm which is computationally less complex (require only exclusive OR operations) and provide better compression efficiency compared to image coding but it is effective for applications having slight changes between adjacent frames of the video. The detection and coding of the Region of Interest (ROIs) in the change frame efficiently reduce the information amount in the change frame. But, if the number of objects in the change frames is higher than a certain level then the compression efficiency of both the change coding and ROI coding becomes worse than that of image coding. This paper explores the compression efficiency of the Binary Video Codec (BVC) for the data reduction in WVSN. We proposed to implement all the three compression techniques i.e. image coding, change coding and ROI coding at the VSN and then select the smallest bit stream among the results of the three compression techniques. In this way the compression performance of the BVC will never become worse than that of image coding. We concluded that the compression efficiency of BVC is always better than that of change coding and is always better than or equal that of ROI coding and image coding.

Hand-held dynamometry in patients with haematological malignancies: Measurement error in the clinical assessment of knee extension strength

PubMed Central

Knols, Ruud H; Aufdemkampe, Geert; de Bruin, Eling D; Uebelhart, Daniel; Aaronson, Neil K

2009-01-01

Background Hand-held dynamometry is a portable and inexpensive method to quantify muscle strength. To determine if muscle strength has changed, an examiner must know what part of the difference between a patient's pre-treatment and post-treatment measurements is attributable to real change, and what part is due to measurement error. This study aimed to determine the relative and absolute reliability of intra and inter-observer strength measurements with a hand-held dynamometer (HHD). Methods Two observers performed maximum voluntary peak torque measurements (MVPT) for isometric knee extension in 24 patients with haematological malignancies. For each patient, the measurements were carried out on the same day. The main outcome measures were the intraclass correlation coefficient (ICC ± 95%CI), the standard error of measurement (SEM), the smallest detectable difference (SDD), the relative values as % of the grand mean of the SEM and SDD, and the limits of agreement for the intra- and inter-observer '3 repetition average' and the 'highest value of 3 MVPT' knee extension strength measures. Results The intra-observer ICCs were 0.94 for the average of 3 MVPT (95%CI: 0.86–0.97) and 0.86 for the highest value of 3 MVPT (95%CI: 0.71–0.94). The ICCs for the inter-observer measurements were 0.89 for the average of 3 MVPT (95%CI: 0.75–0.95) and 0.77 for the highest value of 3 MVPT (95%CI: 0.54–0.90). The SEMs for the intra-observer measurements were 6.22 Nm (3.98% of the grand mean (GM) and 9.83 Nm (5.88% of GM). For the inter-observer measurements, the SEMs were 9.65 Nm (6.65% of GM) and 11.41 Nm (6.73% of GM). The SDDs for the generated parameters varied from 17.23 Nm (11.04% of GM) to 27.26 Nm (17.09% of GM) for intra-observer measurements, and 26.76 Nm (16.77% of GM) to 31.62 Nm (18.66% of GM) for inter-observer measurements, with similar results for the limits of agreement. Conclusion The results indicate that there is acceptable relative reliability for evaluating knee strength with a HHD, while the measurement error observed was modest. The HHD may be useful in detecting changes in knee extension strength at the individual patient level. PMID:19272149