Galaxy evolution and large-scale structure in the far-infrared. I - IRAS pointed observations

NASA Astrophysics Data System (ADS)

Lonsdale, Carol J.; Hacking, Perry B.

1989-04-01

Redshifts for 66 galaxies were obtained from a sample of 93 60-micron sources detected serendipitously in 22 IRAS deep pointed observations, covering a total area of 18.4 sq deg. The flux density limit of this survey is 150 mJy, 4 times fainter than the IRAS Point Source Catalog (PSC). The luminosity function is similar in shape with those previously published for samples selected from the PSC, with a median redshift of 0.048 for the fainter sample, but shifted to higher space densities. There is evidence that some of the excess number counts in the deeper sample can be explained in terms of a large-scale density enhancement beyond the Pavo-Indus supercluster. In addition, the faintest counts in the new sample confirm the result of Hacking et al. (1989) that faint IRAS 60-micron source counts lie significantly in excess of an extrapolation of the PSC counts assuming no luminosity or density evolution.

Galaxy evolution and large-scale structure in the far-infrared. I. IRAS pointed observations

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

Lonsdale, C.J.; Hacking, P.B.

1989-04-01

Redshifts for 66 galaxies were obtained from a sample of 93 60-micron sources detected serendipitously in 22 IRAS deep pointed observations, covering a total area of 18.4 sq deg. The flux density limit of this survey is 150 mJy, 4 times fainter than the IRAS Point Source Catalog (PSC). The luminosity function is similar in shape with those previously published for samples selected from the PSC, with a median redshift of 0.048 for the fainter sample, but shifted to higher space densities. There is evidence that some of the excess number counts in the deeper sample can be explained inmore » terms of a large-scale density enhancement beyond the Pavo-Indus supercluster. In addition, the faintest counts in the new sample confirm the result of Hacking et al. (1989) that faint IRAS 60-micron source counts lie significantly in excess of an extrapolation of the PSC counts assuming no luminosity or density evolution. 81 refs.« less

Galaxy evolution and large-scale structure in the far-infrared. I - IRAS pointed observations

NASA Technical Reports Server (NTRS)

Lonsdale, Carol J.; Hacking, Perry B.

1989-01-01

Redshifts for 66 galaxies were obtained from a sample of 93 60-micron sources detected serendipitously in 22 IRAS deep pointed observations, covering a total area of 18.4 sq deg. The flux density limit of this survey is 150 mJy, 4 times fainter than the IRAS Point Source Catalog (PSC). The luminosity function is similar in shape with those previously published for samples selected from the PSC, with a median redshift of 0.048 for the fainter sample, but shifted to higher space densities. There is evidence that some of the excess number counts in the deeper sample can be explained in terms of a large-scale density enhancement beyond the Pavo-Indus supercluster. In addition, the faintest counts in the new sample confirm the result of Hacking et al. (1989) that faint IRAS 60-micron source counts lie significantly in excess of an extrapolation of the PSC counts assuming no luminosity or density evolution.

Sample to answer visualization pipeline for low-cost point-of-care blood cell counting

NASA Astrophysics Data System (ADS)

Smith, Suzanne; Naidoo, Thegaran; Davies, Emlyn; Fourie, Louis; Nxumalo, Zandile; Swart, Hein; Marais, Philip; Land, Kevin; Roux, Pieter

2015-03-01

We present a visualization pipeline from sample to answer for point-of-care blood cell counting applications. Effective and low-cost point-of-care medical diagnostic tests provide developing countries and rural communities with accessible healthcare solutions [1], and can be particularly beneficial for blood cell count tests, which are often the starting point in the process of diagnosing a patient [2]. The initial focus of this work is on total white and red blood cell counts, using a microfluidic cartridge [3] for sample processing. Analysis of the processed samples has been implemented by means of two main optical visualization systems developed in-house: 1) a fluidic operation analysis system using high speed video data to determine volumes, mixing efficiency and flow rates, and 2) a microscopy analysis system to investigate homogeneity and concentration of blood cells. Fluidic parameters were derived from the optical flow [4] as well as color-based segmentation of the different fluids using a hue-saturation-value (HSV) color space. Cell count estimates were obtained using automated microscopy analysis and were compared to a widely accepted manual method for cell counting using a hemocytometer [5]. The results using the first iteration microfluidic device [3] showed that the most simple - and thus low-cost - approach for microfluidic component implementation was not adequate as compared to techniques based on manual cell counting principles. An improved microfluidic design has been developed to incorporate enhanced mixing and metering components, which together with this work provides the foundation on which to successfully implement automated, rapid and low-cost blood cell counting tests.

Estimating the Effects of Detection Heterogeneity and Overdispersion on Trends Estimated from Avian Point Counts

EPA Science Inventory

Point counts are a common method for sampling avian distribution and abundance. Though methods for estimating detection probabilities are available, many analyses use raw counts and do not correct for detectability. We use a removal model of detection within an N-mixture approa...

Design considerations for examining trends in avian abundance using point counts: examples from oak woodlands

Treesearch

Kathryn L. Purcell; Sylvia R. Mori; Mary K. Chase

2005-01-01

We used data from two oak-woodland sites in California to develop guidelines for the design of bird monitoring programs using point counts. We used power analysis to determine sample size adequacy when varying the number of visits, count stations, and years for examining trends in abundance. We assumed an overdispersed Poisson distribution for count data, with...

Comparison of Birds Detected from Roadside and Off-Road Point Counts in the Shenandoah National Park

Treesearch

Cherry M.E. Keller; Mark R. Fuller

1995-01-01

Roadside point counts are generally used for large surveys to increase the number of samples. We examined differences in species detected from roadside versus off-road (200-m and 400-m) point counts in the Shenandoah National Park. We also compared the list of species detected in the first 3 minutes to those detected in 10 minutes for potential species biases. Results...

IN THAILAND.

PubMed

Luksamijarulkul, Pipat; Suknongbung, Siranee; Vatanasomboon, Pisit; Sujirarut, Dusit

2017-03-01

A large number of migrants have move to cities in Thailand seeking employment. These people may be at increased risk for environmental health problems. We studied the health status, environmental living conditions and microbial indoor air quality (IAQ) among selected groups of migrant workers and their households in Mueang District, Samut Sakhon, central Thailand. We conducted a cross sectional study of 240 migrant workers and their households randomly selected by multistage sampling. The person responsible for hygiene at each studied household was interviewed using a structured questionnaire. Two indoor air samples were taken from each household (480 indoor air samples) to determine bacterial and fungal counts using a Millipore air tester; 240 outdoor air samples were collected for comparison. Ninety-nine point six percent of study subjects were Myanmar, 74.2% were aged 21-40 years, 91.7% had a primary school level education or lower and 53.7% had stayed in Thailand less than 5 years. Eight point three percent had a history of an underlying disease, 20.8% had a recent history of pulmonary tuberculosis in a family member within the previous year. Forty-three point eight percent had a current illness related to IAQ during a previous month. Twenty-one point three were current cigarette smokers, 15.0% were current alcohol consumers, and 5.0% exercises ≥3 times per week. Forty-nine point two percent never opened the windows of their bedrooms or living rooms for ventilation, 45% never cleaned their window screens, and 38.3% never put their pillows or mattresses in the sunlight. The mean(±SD) air bacterial count was 230(±229) CFU/m3 (outdoor air = 128±82 CFU/ m3), and the mean fungal count was 630(±842) CFU/m3 (outdoor air = 138±94 CFU/ m3). When the bacterial and fungal counts were compared with the guidelines of the American Conference of Governmental Industrial Hygienists, the bacterial counts in 6.5% of houses surveyed and the fungal counts in 28.8% of house surveyed were higher than the recommended levels (<500 CFU/m3). Bacterial and fungal counts in the sample households were not significantly correlated with household hygiene practice scores (p>0.05). There was a positive correlation between bacterial counts and fungal counts in household air samples, r=0.28, p<0.001.

Standard error of estimated average timber volume per acre under point sampling when trees are measured for volume on a subsample of all points.

Treesearch

Floyd A. Johnson

1961-01-01

This report assumes a knowledge of the principles of point sampling as described by Grosenbaugh, Bell and Alexander, and others. Whenever trees are counted at every point in a sample of points (large sample) and measured for volume at a portion (small sample) of these points, the sampling design could be called ratio double sampling. If the large...

Reviving common standards in point-count surveys for broad inference across studies

USGS Publications Warehouse

Matsuoka, Steven M.; Mahon, C. Lisa; Handel, Colleen M.; Solymos, Peter; Bayne, Erin M.; Fontaine, Patricia C.; Ralph, C.J.

2014-01-01

We revisit the common standards recommended by Ralph et al. (1993, 1995a) for conducting point-count surveys to assess the relative abundance of landbirds breeding in North America. The standards originated from discussions among ornithologists in 1991 and were developed so that point-count survey data could be broadly compared and jointly analyzed by national data centers with the goals of monitoring populations and managing habitat. Twenty years later, we revisit these standards because (1) they have not been universally followed and (2) new methods allow estimation of absolute abundance from point counts, but these methods generally require data beyond the original standards to account for imperfect detection. Lack of standardization and the complications it introduces for analysis become apparent from aggregated data. For example, only 3% of 196,000 point counts conducted during the period 1992-2011 across Alaska and Canada followed the standards recommended for the count period and count radius. Ten-minute, unlimited-count-radius surveys increased the number of birds detected by >300% over 3-minute, 50-m-radius surveys. This effect size, which could be eliminated by standardized sampling, was ≥10 times the published effect sizes of observers, time of day, and date of the surveys. We suggest that the recommendations by Ralph et al. (1995a) continue to form the common standards when conducting point counts. This protocol is inexpensive and easy to follow but still allows the surveys to be adjusted for detection probabilities. Investigators might optionally collect additional information so that they can analyze their data with more flexible forms of removal and time-of-detection models, distance sampling, multiple-observer methods, repeated counts, or combinations of these methods. Maintaining the common standards as a base protocol, even as these study-specific modifications are added, will maximize the value of point-count data, allowing compilation and analysis by regional and national data centers.

Spatial distribution of Legionella pneumophila MLVA-genotypes in a drinking water system.

PubMed

Rodríguez-Martínez, Sarah; Sharaby, Yehonatan; Pecellín, Marina; Brettar, Ingrid; Höfle, Manfred; Halpern, Malka

2015-06-15

Bacteria of the genus Legionella cause water-based infections, resulting in severe pneumonia. To improve our knowledge about Legionella spp. ecology, its prevalence and its relationships with environmental factors were studied. Seasonal samples were taken from both water and biofilm at seven sampling points of a small drinking water distribution system in Israel. Representative isolates were obtained from each sample and identified to the species level. Legionella pneumophila was further determined to the serotype and genotype level. High resolution genotyping of L. pneumophila isolates was achieved by Multiple-Locus Variable number of tandem repeat Analysis (MLVA). Within the studied water system, Legionella plate counts were higher in summer and highly variable even between adjacent sampling points. Legionella was present in six out of the seven selected sampling points, with counts ranging from 1.0 × 10(1) to 5.8 × 10(3) cfu/l. Water counts were significantly higher in points where Legionella was present in biofilms. The main fraction of the isolated Legionella was L. pneumophila serogroup 1. Serogroup 3 and Legionella sainthelensis were also isolated. Legionella counts were positively correlated with heterotrophic plate counts at 37 °C and negatively correlated with chlorine. Five MLVA-genotypes of L. pneumophila were identified at different buildings of the sampled area. The presence of a specific genotype, "MLVA-genotype 4", consistently co-occurred with high Legionella counts and seemed to "trigger" high Legionella counts in cold water. Our hypothesis is that both the presence of L. pneumophila in biofilm and the presence of specific genotypes, may indicate and/or even lead to high Legionella concentration in water. This observation deserves further studies in a broad range of drinking water systems to assess its potential for general use in drinking water monitoring and management. Copyright © 2015 Elsevier Ltd. All rights reserved.

Protocol for monitoring forest-nesting birds in National Park Service parks

USGS Publications Warehouse

Dawson, Deanna K.; Efford, Murray G.

2013-01-01

These documents detail the protocol for monitoring forest-nesting birds in National Park Service parks in the National Capital Region Network (NCRN). In the first year of sampling, counts of birds should be made at 384 points on the NCRN spatially randomized grid, developed to sample terrestrial resources. Sampling should begin on or about May 20 and continue into early July; on each day the sampling period begins at sunrise and ends five hours later. Each point should be counted twice, once in the first half of the field season and once in the second half, with visits made by different observers, balancing the within-season coverage of points and their spatial coverage by observers, and allowing observer differences to be tested. Three observers, skilled in identifying birds of the region by sight and sound and with previous experience in conducting timed counts of birds, will be needed for this effort. Observers should be randomly assigned to ‘routes’ consisting of eight points, in close proximity and, ideally, in similar habitat, that can be covered in one morning. Counts are 10 minutes in length, subdivided into four 2.5-min intervals. Within each time interval, new birds (i.e., those not already detected) are recorded as within or beyond 50 m of the point, based on where first detected. Binomial distance methods are used to calculate annual estimates of density for species. The data are also amenable to estimation of abundance and detection probability via the removal method. Generalized linear models can be used to assess between-year changes in density estimates or unadjusted count data. This level of sampling is expected to be sufficient to detect a 50% decline in 10 years for approximately 50 bird species, including 14 of 19 species that are priorities for conservation efforts, if analyses are based on unadjusted count data, and for 30 species (6 priority species) if analyses are based on density estimates. The estimates of required sample sizes are based on the mean number of individuals detected per 10 minutes in available data from surveys in three NCRN parks. Once network-wide data from the first year of sampling are available, this and other aspects of the protocol should be re-assessed, and changes made as desired or necessary before the start of the second field season. Thereafter, changes should not be made to the field methods, and sampling should be conducted annually for at least ten years. NCRN staff should keep apprised of new analytical methods developed for analysis of point-count data.

Comparison of birds detected from roadside and off-road point counts in the Shenandoah National Park

USGS Publications Warehouse

Keller, C.M.E.; Fuller, M.R.; Ralph, C. John; Sauer, John R.; Droege, Sam

1995-01-01

Roadside point counts are generally used for large surveys to increase the number of samples. We examined differences in species detected from roadside versus off-road (200-m and 400-ha) point counts in the Shenandoah National Park. We also compared the list of species detected in the first 3 minutes to those detected in 10 minutes for potential species biases. Results from 81 paired roadside and off-road counts indicated that roadside counts had higher numbers of several edge species but did not have lower numbers of nonedge forest species. More individuals and species were detected from roadside points because of this increase in edge species. Sixty-five percent of the species detected in 10 minutes were recorded in the first 3 minutes.

Detectability of Forest Birds from Stationary Points in Northern Wisconsin

Treesearch

Amy T. Wolf; Robert W. Howe; Gregory J. Davis

1995-01-01

Estimation of avian densities from point counts requires information about the distance at which birds can be detected by the observer. Detection distances also are important for designing the spacing of point counts in a regional sampling scheme. We examined the relationship between distance and detectability for forest songbirds in northern Wisconsin. Like previous...

Accuracy or precision: Implications of sample design and methodology on abundance estimation

USGS Publications Warehouse

Kowalewski, Lucas K.; Chizinski, Christopher J.; Powell, Larkin A.; Pope, Kevin L.; Pegg, Mark A.

2015-01-01

Sampling by spatially replicated counts (point-count) is an increasingly popular method of estimating population size of organisms. Challenges exist when sampling by point-count method, and it is often impractical to sample entire area of interest and impossible to detect every individual present. Ecologists encounter logistical limitations that force them to sample either few large-sample units or many small sample-units, introducing biases to sample counts. We generated a computer environment and simulated sampling scenarios to test the role of number of samples, sample unit area, number of organisms, and distribution of organisms in the estimation of population sizes using N-mixture models. Many sample units of small area provided estimates that were consistently closer to true abundance than sample scenarios with few sample units of large area. However, sample scenarios with few sample units of large area provided more precise abundance estimates than abundance estimates derived from sample scenarios with many sample units of small area. It is important to consider accuracy and precision of abundance estimates during the sample design process with study goals and objectives fully recognized, although and with consequence, consideration of accuracy and precision of abundance estimates is often an afterthought that occurs during the data analysis process.

Incorporating availability for detection in estimates of bird abundance

USGS Publications Warehouse

Diefenbach, D.R.; Marshall, M.R.; Mattice, J.A.; Brauning, D.W.

2007-01-01

Several bird-survey methods have been proposed that provide an estimated detection probability so that bird-count statistics can be used to estimate bird abundance. However, some of these estimators adjust counts of birds observed by the probability that a bird is detected and assume that all birds are available to be detected at the time of the survey. We marked male Henslow's Sparrows (Ammodramus henslowii) and Grasshopper Sparrows (A. savannarum) and monitored their behavior during May-July 2002 and 2003 to estimate the proportion of time they were available for detection. We found that the availability of Henslow's Sparrows declined in late June to <10% for 5- or 10-min point counts when a male had to sing and be visible to the observer; but during 20 May-19 June, males were available for detection 39.1% (SD = 27.3) of the time for 5-min point counts and 43.9% (SD = 28.9) of the time for 10-min point counts (n = 54). We detected no temporal changes in availability for Grasshopper Sparrows, but estimated availability to be much lower for 5-min point counts (10.3%, SD = 12.2) than for 10-min point counts (19.2%, SD = 22.3) when males had to be visible and sing during the sampling period (n = 80). For distance sampling, we estimated the availability of Henslow's Sparrows to be 44.2% (SD = 29.0) and the availability of Grasshopper Sparrows to be 20.6% (SD = 23.5). We show how our estimates of availability can be incorporated in the abundance and variance estimators for distance sampling and modify the abundance and variance estimators for the double-observer method. Methods that directly estimate availability from bird counts but also incorporate detection probabilities need further development and will be important for obtaining unbiased estimates of abundance for these species.

A statistical model investigating the prevalence of tuberculosis in New York City using counting processes with two change-points

PubMed Central

ACHCAR, J. A.; MARTINEZ, E. Z.; RUFFINO-NETTO, A.; PAULINO, C. D.; SOARES, P.

2008-01-01

SUMMARY We considered a Bayesian analysis for the prevalence of tuberculosis cases in New York City from 1970 to 2000. This counting dataset presented two change-points during this period. We modelled this counting dataset considering non-homogeneous Poisson processes in the presence of the two-change points. A Bayesian analysis for the data is considered using Markov chain Monte Carlo methods. Simulated Gibbs samples for the parameters of interest were obtained using WinBugs software. PMID:18346287

Generalized estimators of avian abundance from count survey data

USGS Publications Warehouse

Royle, J. Andrew

2004-01-01

I consider modeling avian abundance from spatially referenced bird count data collected according to common protocols such as capture?recapture, multiple observer, removal sampling and simple point counts. Small sample sizes and large numbers of parameters have motivated many analyses that disregard the spatial indexing of the data, and thus do not provide an adequate treatment of spatial structure. I describe a general framework for modeling spatially replicated data that regards local abundance as a random process, motivated by the view that the set of spatially referenced local populations (at the sample locations) constitute a metapopulation. Under this view, attention can be focused on developing a model for the variation in local abundance independent of the sampling protocol being considered. The metapopulation model structure, when combined with the data generating model, define a simple hierarchical model that can be analyzed using conventional methods. The proposed modeling framework is completely general in the sense that broad classes of metapopulation models may be considered, site level covariates on detection and abundance may be considered, and estimates of abundance and related quantities may be obtained for sample locations, groups of locations, unsampled locations. Two brief examples are given, the first involving simple point counts, and the second based on temporary removal counts. Extension of these models to open systems is briefly discussed.

40 CFR Appendix E to Subpart E of... - Interim Method of the Determination of Asbestos in Bulk Insulation Samples

Code of Federal Regulations, 2014 CFR

2014-07-01

... characteristics of anisotropic particles. Quantitative analysis involves the use of point counting. Point counting... 0.004. • Refractive Index Liquids for Dispersion Staining: high-dispersion series, 1.550, 1.605, 1... hand. Repeat the series. Collect the dispersed solids by centrifugation at 1000 rpm for 5 minutes. Wash...

40 CFR Appendix E to Subpart E of... - Interim Method of the Determination of Asbestos in Bulk Insulation Samples

Code of Federal Regulations, 2010 CFR

2010-07-01

... characteristics of anisotropic particles. Quantitative analysis involves the use of point counting. Point counting... 0.004. • Refractive Index Liquids for Dispersion Staining: high-dispersion series, 1.550, 1.605, 1... hand. Repeat the series. Collect the dispersed solids by centrifugation at 1000 rpm for 5 minutes. Wash...

40 CFR Appendix E to Subpart E of... - Interim Method of the Determination of Asbestos in Bulk Insulation Samples

Code of Federal Regulations, 2011 CFR

2011-07-01

... characteristics of anisotropic particles. Quantitative analysis involves the use of point counting. Point counting... 0.004. • Refractive Index Liquids for Dispersion Staining: high-dispersion series, 1.550, 1.605, 1... hand. Repeat the series. Collect the dispersed solids by centrifugation at 1000 rpm for 5 minutes. Wash...

40 CFR Appendix E to Subpart E of... - Interim Method of the Determination of Asbestos in Bulk Insulation Samples

Code of Federal Regulations, 2012 CFR

2012-07-01

... characteristics of anisotropic particles. Quantitative analysis involves the use of point counting. Point counting... 0.004. • Refractive Index Liquids for Dispersion Staining: high-dispersion series, 1.550, 1.605, 1... hand. Repeat the series. Collect the dispersed solids by centrifugation at 1000 rpm for 5 minutes. Wash...

40 CFR Appendix E to Subpart E of... - Interim Method of the Determination of Asbestos in Bulk Insulation Samples

Code of Federal Regulations, 2013 CFR

2013-07-01

... characteristics of anisotropic particles. Quantitative analysis involves the use of point counting. Point counting... 0.004. • Refractive Index Liquids for Dispersion Staining: high-dispersion series, 1.550, 1.605, 1... hand. Repeat the series. Collect the dispersed solids by centrifugation at 1000 rpm for 5 minutes. Wash...

Recursive algorithms for phylogenetic tree counting.

PubMed

Gavryushkina, Alexandra; Welch, David; Drummond, Alexei J

2013-10-28

In Bayesian phylogenetic inference we are interested in distributions over a space of trees. The number of trees in a tree space is an important characteristic of the space and is useful for specifying prior distributions. When all samples come from the same time point and no prior information available on divergence times, the tree counting problem is easy. However, when fossil evidence is used in the inference to constrain the tree or data are sampled serially, new tree spaces arise and counting the number of trees is more difficult. We describe an algorithm that is polynomial in the number of sampled individuals for counting of resolutions of a constraint tree assuming that the number of constraints is fixed. We generalise this algorithm to counting resolutions of a fully ranked constraint tree. We describe a quadratic algorithm for counting the number of possible fully ranked trees on n sampled individuals. We introduce a new type of tree, called a fully ranked tree with sampled ancestors, and describe a cubic time algorithm for counting the number of such trees on n sampled individuals. These algorithms should be employed for Bayesian Markov chain Monte Carlo inference when fossil data are included or data are serially sampled.

Bird biodiversity assessments in temperate forest: the value of point count versus acoustic monitoring protocols.

PubMed

Klingbeil, Brian T; Willig, Michael R

2015-01-01

Effective monitoring programs for biodiversity are needed to assess trends in biodiversity and evaluate the consequences of management. This is particularly true for birds and faunas that occupy interior forest and other areas of low human population density, as these are frequently under-sampled compared to other habitats. For birds, Autonomous Recording Units (ARUs) have been proposed as a supplement or alternative to point counts made by human observers to enhance monitoring efforts. We employed two strategies (i.e., simultaneous-collection and same-season) to compare point count and ARU methods for quantifying species richness and composition of birds in temperate interior forests. The simultaneous-collection strategy compares surveys by ARUs and point counts, with methods matched in time, location, and survey duration such that the person and machine simultaneously collect data. The same-season strategy compares surveys from ARUs and point counts conducted at the same locations throughout the breeding season, but methods differ in the number, duration, and frequency of surveys. This second strategy more closely follows the ways in which monitoring programs are likely to be implemented. Site-specific estimates of richness (but not species composition) differed between methods; however, the nature of the relationship was dependent on the assessment strategy. Estimates of richness from point counts were greater than estimates from ARUs in the simultaneous-collection strategy. Woodpeckers in particular, were less frequently identified from ARUs than point counts with this strategy. Conversely, estimates of richness were lower from point counts than ARUs in the same-season strategy. Moreover, in the same-season strategy, ARUs detected the occurrence of passerines at a higher frequency than did point counts. Differences between ARU and point count methods were only detected in site-level comparisons. Importantly, both methods provide similar estimates of species richness and composition for the region. Consequently, if single visits to sites or short-term monitoring are the goal, point counts will likely perform better than ARUs, especially if species are rare or vocalize infrequently. However, if seasonal or annual monitoring of sites is the goal, ARUs offer a viable alternative to standard point-count methods, especially in the context of large-scale or long-term monitoring of temperate forest birds.

Spatially explicit models for inference about density in unmarked or partially marked populations

USGS Publications Warehouse

Chandler, Richard B.; Royle, J. Andrew

2013-01-01

Recently developed spatial capture–recapture (SCR) models represent a major advance over traditional capture–recapture (CR) models because they yield explicit estimates of animal density instead of population size within an unknown area. Furthermore, unlike nonspatial CR methods, SCR models account for heterogeneity in capture probability arising from the juxtaposition of animal activity centers and sample locations. Although the utility of SCR methods is gaining recognition, the requirement that all individuals can be uniquely identified excludes their use in many contexts. In this paper, we develop models for situations in which individual recognition is not possible, thereby allowing SCR concepts to be applied in studies of unmarked or partially marked populations. The data required for our model are spatially referenced counts made on one or more sample occasions at a collection of closely spaced sample units such that individuals can be encountered at multiple locations. Our approach includes a spatial point process for the animal activity centers and uses the spatial correlation in counts as information about the number and location of the activity centers. Camera-traps, hair snares, track plates, sound recordings, and even point counts can yield spatially correlated count data, and thus our model is widely applicable. A simulation study demonstrated that while the posterior mean exhibits frequentist bias on the order of 5–10% in small samples, the posterior mode is an accurate point estimator as long as adequate spatial correlation is present. Marking a subset of the population substantially increases posterior precision and is recommended whenever possible. We applied our model to avian point count data collected on an unmarked population of the northern parula (Parula americana) and obtained a density estimate (posterior mode) of 0.38 (95% CI: 0.19–1.64) birds/ha. Our paper challenges sampling and analytical conventions in ecology by demonstrating that neither spatial independence nor individual recognition is needed to estimate population density—rather, spatial dependence can be informative about individual distribution and density.

SU-E-I-79: Source Geometry Dependence of Gamma Well-Counter Measurements

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

Park, M; Belanger, A; Kijewski, M

Purpose: To determine the effect of liquid sample volume and geometry on counting efficiency in a gamma well-counter, and to assess the relative contributions of sample geometry and self-attenuation. Gamma wellcounters are standard equipment in clinical and preclinical studies, for measuring patient blood radioactivity and quantifying animal tissue uptake for tracer development and other purposes. Accurate measurements are crucial. Methods: Count rates were measured for aqueous solutions of 99m- Tc at four liquid volume values in a 1-cm-diam tube and at six volume values in a 2.2-cm-diam vial. Total activity was constant for all volumes, and data were corrected formore » decay. Count rates from a point source in air, supported by a filter paper, were measured at seven heights between 1.3 and 5.7 cm from the bottom of a tube. Results: Sample volume effects were larger for the tube than for the vial. For the tube, count efficiency relative to a 1-cc volume ranged from 1.05 at 0.05 cc to 0.84 at 3 cc. For the vial, relative count efficiency ranged from 1.02 at 0.05 cc to 0.87 at 15 cc. For the point source, count efficiency relative to 1.3 cm from the tube bottom ranged from 0.98 at 1.8 cm to 0.34 at 5.7 cm. The relative efficiency of a 3-cc liquid sample in a tube compared to a 1-cc sample is 0.84; the average relative efficiency for the solid sample in air between heights in the tube corresponding to the surfaces of those volumes (1.3 and 4.8 cm) is 0.81, implying that the major contribution to efficiency loss is geometry, rather than attenuation. Conclusion: Volume-dependent correction factors should be used for accurate quantitation radioactive of liquid samples. Solid samples should be positioned at the bottom of the tube for maximum count efficiency.« less

Experimental Design Considerations for Establishing an Off-Road, Habitat-Specific Bird Monitoring Program Using Point Counts

Treesearch

JoAnn M. Hanowski; Gerald J. Niemi

1995-01-01

We established bird monitoring programs in two regions of Minnesota: the Chippewa National Forest and the Superior National Forest. The experimental design defined forest cover types as strata in which samples of forest stands were randomly selected. Subsamples (3 point counts) were placed in each stand to maximize field effort and to assess within-stand and between-...

Effect of distance-related heterogeneity on population size estimates from point counts

USGS Publications Warehouse

Efford, Murray G.; Dawson, Deanna K.

2009-01-01

Point counts are used widely to index bird populations. Variation in the proportion of birds counted is a known source of error, and for robust inference it has been advocated that counts be converted to estimates of absolute population size. We used simulation to assess nine methods for the conduct and analysis of point counts when the data included distance-related heterogeneity of individual detection probability. Distance from the observer is a ubiquitous source of heterogeneity, because nearby birds are more easily detected than distant ones. Several recent methods (dependent double-observer, time of first detection, time of detection, independent multiple-observer, and repeated counts) do not account for distance-related heterogeneity, at least in their simpler forms. We assessed bias in estimates of population size by simulating counts with fixed radius w over four time intervals (occasions). Detection probability per occasion was modeled as a half-normal function of distance with scale parameter sigma and intercept g(0) = 1.0. Bias varied with sigma/w; values of sigma inferred from published studies were often 50% for a 100-m fixed-radius count. More critically, the bias of adjusted counts sometimes varied more than that of unadjusted counts, and inference from adjusted counts would be less robust. The problem was not solved by using mixture models or including distance as a covariate. Conventional distance sampling performed well in simulations, but its assumptions are difficult to meet in the field. We conclude that no existing method allows effective estimation of population size from point counts.

7 CFR 51.628 - Tolerances.

Code of Federal Regulations, 2011 CFR

2011-01-01

...—Shipping Point 1 (A) For 1 through 20 Samples Factor Grades AL 2 Number of 33-count samples 3 1 2 3 4 5 6 7.... 2 Russet. Table I—Shipping Point 1 (Continued) (B) For 21 through 40 Samples Factor Grades AL 2... outside the continental United States, the port of entry into the United States. 2 AL—Absolute limit...

7 CFR 51.628 - Tolerances.

Code of Federal Regulations, 2012 CFR

2012-01-01

...—Shipping Point 1 (A) For 1 through 20 Samples Factor Grades AL 2 Number of 33-count samples 3 1 2 3 4 5 6 7.... 2 Russet. Table I—Shipping Point 1 (Continued) (B) For 21 through 40 Samples Factor Grades AL 2... outside the continental United States, the port of entry into the United States. 2 AL—Absolute limit...

7 CFR 51.628 - Tolerances.

Code of Federal Regulations, 2010 CFR

2010-01-01

...—Shipping Point 1 (A) For 1 through 20 Samples Factor Grades AL 2 Number of 33-count samples 3 1 2 3 4 5 6 7.... 2 Russet. Table I—Shipping Point 1 (Continued) (B) For 21 through 40 Samples Factor Grades AL 2... outside the continental United States, the port of entry into the United States. 2 AL—Absolute limit...

Combining Breeding Bird Survey and distance sampling to estimate density of migrant and breeding birds

USGS Publications Warehouse

Somershoe, S.G.; Twedt, D.J.; Reid, B.

2006-01-01

We combined Breeding Bird Survey point count protocol and distance sampling to survey spring migrant and breeding birds in Vicksburg National Military Park on 33 days between March and June of 2003 and 2004. For 26 of 106 detected species, we used program DISTANCE to estimate detection probabilities and densities from 660 3-min point counts in which detections were recorded within four distance annuli. For most species, estimates of detection probability, and thereby density estimates, were improved through incorporation of the proportion of forest cover at point count locations as a covariate. Our results suggest Breeding Bird Surveys would benefit from the use of distance sampling and a quantitative characterization of habitat at point count locations. During spring migration, we estimated that the most common migrant species accounted for a population of 5000-9000 birds in Vicksburg National Military Park (636 ha). Species with average populations of 300 individuals during migration were: Blue-gray Gnatcatcher (Polioptila caerulea), Cedar Waxwing (Bombycilla cedrorum), White-eyed Vireo (Vireo griseus), Indigo Bunting (Passerina cyanea), and Ruby-crowned Kinglet (Regulus calendula). Of 56 species that bred in Vicksburg National Military Park, we estimated that the most common 18 species accounted for 8150 individuals. The six most abundant breeding species, Blue-gray Gnatcatcher, White-eyed Vireo, Summer Tanager (Piranga rubra), Northern Cardinal (Cardinalis cardinalis), Carolina Wren (Thryothorus ludovicianus), and Brown-headed Cowbird (Molothrus ater), accounted for 5800 individuals.

Assessment of frequency and duration of point counts when surveying for golden eagle presence

USGS Publications Warehouse

Skipper, Ben R.; Boal, Clint W.; Tsai, Jo-Szu; Fuller, Mark R.

2017-01-01

We assessed the utility of the recommended golden eagle (Aquila chrysaetos) survey methodology in the U.S. Fish and Wildlife Service 2013 Eagle Conservation Plan Guidance. We conducted 800-m radius, 1-hr point-count surveys broken into 20-min segments, during 2 sampling periods in 3 areas within the Intermountain West of the United States over 2 consecutive breeding seasons during 2012 and 2013. Our goal was to measure the influence of different survey time intervals and sampling periods on detectability and use estimates of golden eagles among different locations. Our results suggest that a less intensive effort (i.e., survey duration shorter than 1 hr and point-count survey radii smaller than 800 m) would likely be inadequate for rigorous documentation of golden eagle occurrence pre- or postconstruction of wind energy facilities. Results from a simulation analysis of detection probabilities and survey effort suggest that greater temporal and spatial effort could make point-count surveys more applicable for evaluating golden eagle occurrence in survey areas; however, increased effort would increase financial costs associated with additional person-hours and logistics (e.g., fuel, lodging). Future surveys can benefit from a pilot study and careful consideration of prior information about counts or densities of golden eagles in the survey area before developing a survey design. If information is lacking, survey planning may be best served by assuming low detection rates and increasing the temporal and spatial effort.

A double-observer approach for estimating detection probability and abundance from point counts

USGS Publications Warehouse

Nichols, J.D.; Hines, J.E.; Sauer, J.R.; Fallon, F.W.; Fallon, J.E.; Heglund, P.J.

2000-01-01

Although point counts are frequently used in ornithological studies, basic assumptions about detection probabilities often are untested. We apply a double-observer approach developed to estimate detection probabilities for aerial surveys (Cook and Jacobson 1979) to avian point counts. At each point count, a designated 'primary' observer indicates to another ('secondary') observer all birds detected. The secondary observer records all detections of the primary observer as well as any birds not detected by the primary observer. Observers alternate primary and secondary roles during the course of the survey. The approach permits estimation of observer-specific detection probabilities and bird abundance. We developed a set of models that incorporate different assumptions about sources of variation (e.g. observer, bird species) in detection probability. Seventeen field trials were conducted, and models were fit to the resulting data using program SURVIV. Single-observer point counts generally miss varying proportions of the birds actually present, and observer and bird species were found to be relevant sources of variation in detection probabilities. Overall detection probabilities (probability of being detected by at least one of the two observers) estimated using the double-observer approach were very high (>0.95), yielding precise estimates of avian abundance. We consider problems with the approach and recommend possible solutions, including restriction of the approach to fixed-radius counts to reduce the effect of variation in the effective radius of detection among various observers and to provide a basis for using spatial sampling to estimate bird abundance on large areas of interest. We believe that most questions meriting the effort required to carry out point counts also merit serious attempts to estimate detection probabilities associated with the counts. The double-observer approach is a method that can be used for this purpose.

A New Method for Calculating Counts in Cells

NASA Astrophysics Data System (ADS)

Szapudi, István

1998-04-01

In the near future, a new generation of CCD-based galaxy surveys will enable high-precision determination of the N-point correlation functions. The resulting information will help to resolve the ambiguities associated with two-point correlation functions, thus constraining theories of structure formation, biasing, and Gaussianity of initial conditions independently of the value of Ω. As one of the most successful methods of extracting the amplitude of higher order correlations is based on measuring the distribution of counts in cells, this work presents an advanced way of measuring it with unprecedented accuracy. Szapudi & Colombi identified the main sources of theoretical errors in extracting counts in cells from galaxy catalogs. One of these sources, termed as measurement error, stems from the fact that conventional methods use a finite number of sampling cells to estimate counts in cells. This effect can be circumvented by using an infinite number of cells. This paper presents an algorithm, which in practice achieves this goal; that is, it is equivalent to throwing an infinite number of sampling cells in finite time. The errors associated with sampling cells are completely eliminated by this procedure, which will be essential for the accurate analysis of future surveys.

Establishing school day pedometer step count cut-points using ROC curves in low-income children.

PubMed

Burns, Ryan D; Brusseau, Timothy A; Fu, You; Hannon, James C

2016-05-01

Previous research has not established pedometer step count cut-points that discriminate children that meet school day physical activity recommendations using a tri-axial ActiGraph accelerometer criterion. The purpose of this study was to determine step count cut-points that associate with 30min of school day moderate-to-vigorous physical activity (MVPA) in school-aged children. Participants included 1053 school-aged children (mean age=8.4±1.8years) recruited from three low-income schools from the state of Utah in the U.S. Physical activity was assessed using Yamax DigiWalker CW600 pedometers and ActiGraph wGT3X-BT triaxial accelerometers that were concurrently worn during school hours. Data were collected at each school during the 2014-2015 school year. Receiver operating characteristic (ROC) curves were used to determine pedometer step count cut-points that associated with at least 30min of MVPA during school hours. Cut-points were determined using the maximum Youden's J statistic (J max). For the total sample, the area-under-the-curve (AUC) was 0.77 (p<0.001) with a pedometer cut-point of 5505 steps (J max=0.46, Sensitivity=63%, Specificity=84%; Accuracy=76%). Step counts showed greater diagnostic ability in girls (AUC=0.81, p<0.001; Cut-point=5306 steps; Accuracy=78.8%) compared to boys (AUC=0.72, p<0.01; Cut-point=5786 steps; Accuracy=71.4%). Pedometer step counts showed good diagnostic ability in girls and fair diagnostic ability in boys for discriminating children that met at least 30min of MVPA during school hours. Copyright © 2016 Elsevier Inc. All rights reserved.

Field test comparison of an autocorrelation technique for determining grain size using a digital 'beachball' camera versus traditional methods

USGS Publications Warehouse

Barnard, P.L.; Rubin, D.M.; Harney, J.; Mustain, N.

2007-01-01

This extensive field test of an autocorrelation technique for determining grain size from digital images was conducted using a digital bed-sediment camera, or 'beachball' camera. Using 205 sediment samples and >1200 images from a variety of beaches on the west coast of the US, grain size ranging from sand to granules was measured from field samples using both the autocorrelation technique developed by Rubin [Rubin, D.M., 2004. A simple autocorrelation algorithm for determining grain size from digital images of sediment. Journal of Sedimentary Research, 74(1): 160-165.] and traditional methods (i.e. settling tube analysis, sieving, and point counts). To test the accuracy of the digital-image grain size algorithm, we compared results with manual point counts of an extensive image data set in the Santa Barbara littoral cell. Grain sizes calculated using the autocorrelation algorithm were highly correlated with the point counts of the same images (r2 = 0.93; n = 79) and had an error of only 1%. Comparisons of calculated grain sizes and grain sizes measured from grab samples demonstrated that the autocorrelation technique works well on high-energy dissipative beaches with well-sorted sediment such as in the Pacific Northwest (r2 ??? 0.92; n = 115). On less dissipative, more poorly sorted beaches such as Ocean Beach in San Francisco, results were not as good (r2 ??? 0.70; n = 67; within 3% accuracy). Because the algorithm works well compared with point counts of the same image, the poorer correlation with grab samples must be a result of actual spatial and vertical variability of sediment in the field; closer agreement between grain size in the images and grain size of grab samples can be achieved by increasing the sampling volume of the images (taking more images, distributed over a volume comparable to that of a grab sample). In all field tests the autocorrelation method was able to predict the mean and median grain size with ???96% accuracy, which is more than adequate for the majority of sedimentological applications, especially considering that the autocorrelation technique is estimated to be at least 100 times faster than traditional methods.

[Physico-chemical and microbiological evaluation of UHT milk commercialized in three Mercosul countries (Brazil, Argentina and Paraguay)].

PubMed

Domareski, Jackson Luiz; Bandiera, Nataly Simões; Sato, Rafael Tamostu; Aragon-Alegro, Lina Casale; de Santana, Elsa Helena Walter

2010-09-01

With the aim to evaluate the physico-chemical and microbiological quality of UHT milk commercialized in three countries of Mercosul, samples of four different brands were acquired in each city (Foz do Iguaçu-Brazil, Puerto Iguazú-Argentina and Ciudad del Este-Paraguay) and submitted to the following analysis: fat content, titratable acidity, milk ethanol stability (with the following ethanol concentrations: 68, 72, 76 and 80%), total dry extract and no fat dry extract, pH, density and freezing point. Counts of mesophilic and psychrotrophic microorganisms were already done. In the physico-chemical evaluation of UHT milk, a significant number of samples were in disagree with the established patterns for fat content, no fat dry extract, density and freezing point. Except one brand from Brazil, milk samples showed stability to 68% ethanol. pH averages of Brazilian milk were in agree with the patterns and highest values were observed in samples acquired on Paraguay. Observing the microbiological analysis, 37.5%, 62.5% and 12.5% of samples acquired from Brazil, Argentina and Paraguay, respectively, showed counts above the established patterns for mesophilic microorganisms. Counts of psychrotrophic microorganisms were in disagree with the established patterns in 50%, 50% and 100% of samples from Brazil, Argentina and Paraguay, respectively.

Validation of a quantitative Eimeria spp. PCR for fresh droppings of broiler chickens.

PubMed

Peek, H W; Ter Veen, C; Dijkman, R; Landman, W J M

2017-12-01

A quantitative Polymerase Chain Reaction (qPCR) for the seven chicken Eimeria spp. was modified and validated for direct use on fresh droppings. The analytical specificity of the qPCR on droppings was 100%. Its analytical sensitivity (non-sporulated oocysts/g droppings) was 41 for E. acervulina, ≤2900 for E. brunetti, 710 for E. praecox, 1500 for E. necatrix, 190 for E. tenella, 640 for E. maxima, and 1100 for E. mitis. Field validation of the qPCR was done using droppings with non-sporulated oocysts from 19 broiler flocks. To reduce the number of qPCR tests five grams of each pooled sample (consisting of ten fresh droppings) per time point were blended into one mixed sample. Comparison of the oocysts per gram (OPG)-counting method with the qPCR using pooled samples (n = 1180) yielded a Pearson's correlation coefficient of 0.78 (95% CI: 0.76-0.80) and a Pearson's correlation coefficient of 0.76 (95% CI: 0.70-0.81) using mixed samples (n = 236). Comparison of the average of the OPG-counts of the five pooled samples with the mixed sample per time point (n = 236) showed a Pearson's correlation coefficient (R) of 0.94 (95% CI: 0.92-0.95) for the OPG-counting method and 0.87 (95% CI: 0.84-0.90) for the qPCR. This indicates that mixed samples are practically equivalent to the mean of five pooled samples. The good correlation between the OPG-counting method and the qPCR was further confirmed by the visual agreement between the total oocyst/g shedding patterns measured with both techniques in the 19 broiler flocks using the mixed samples.

Estimating pore and cement volumes in thin section

USGS Publications Warehouse

Halley, R.B.

1978-01-01

Point count estimates of pore, grain and cement volumes from thin sections are inaccurate, often by more than 100 percent, even though they may be surprisingly precise (reproducibility + or - 3 percent). Errors are produced by: 1) inclusion of submicroscopic pore space within solid volume and 2) edge effects caused by grain curvature within a 30-micron thick thin section. Submicroscopic porosity may be measured by various physical tests or may be visually estimated from scanning electron micrographs. Edge error takes the form of an envelope around grains and increases with decreasing grain size and sorting, increasing grain irregularity and tighter grain packing. Cements are greatly involved in edge error because of their position at grain peripheries and their generally small grain size. Edge error is minimized by methods which reduce the thickness of the sample viewed during point counting. Methods which effectively reduce thickness include use of ultra-thin thin sections or acetate peels, point counting in reflected light, or carefully focusing and counting on the upper surface of the thin section.

Inference about density and temporary emigration in unmarked populations

USGS Publications Warehouse

Chandler, Richard B.; Royle, J. Andrew; King, David I.

2011-01-01

Few species are distributed uniformly in space, and populations of mobile organisms are rarely closed with respect to movement, yet many models of density rely upon these assumptions. We present a hierarchical model allowing inference about the density of unmarked populations subject to temporary emigration and imperfect detection. The model can be fit to data collected using a variety of standard survey methods such as repeated point counts in which removal sampling, double-observer sampling, or distance sampling is used during each count. Simulation studies demonstrated that parameter estimators are unbiased when temporary emigration is either "completely random" or is determined by the size and location of home ranges relative to survey points. We also applied the model to repeated removal sampling data collected on Chestnut-sided Warblers (Dendroica pensylvancia) in the White Mountain National Forest, USA. The density estimate from our model, 1.09 birds/ha, was similar to an estimate of 1.11 birds/ha produced by an intensive spot-mapping effort. Our model is also applicable when processes other than temporary emigration affect the probability of being available for detection, such as in studies using cue counts. Functions to implement the model have been added to the R package unmarked.

Survey of fungal counts and natural occurrence of aflatoxins in Malaysian starch-based foods.

PubMed

Abdullah, N; Nawawi, A; Othman, I

1998-01-01

In a survey of starch-based foods sampled from retail outlets in Malaysia, fungal colonies were mostly detected in wheat flour (100%), followed by rice flour (74%), glutinous rice grains (72%), ordinary rice grains (60%), glutinous rice flour (48%) and corn flour (26%). All positive samples of ordinary rice and glutinous rice grains had total fungal counts below 10(3) cfu/g sample, while among the positive rice flour, glutinous rice flour and corn flour samples, the highest total fungal count was more than 10(3) but less than 10(4) cfu/g sample respectively. However, in wheat flour samples total fungal count ranged from 10(2) cfu/g sample to slightly more than 10(4) cfu/g sample. Aflatoxigenic colonies were mostly detected in wheat flour (20%), followed by ordinary rice grains (4%), glutinous rice grains (4%) and glutinous rice flour (2%). No aflatoxigenic colonies were isolated from rice flour and corn flour samples. Screening of aflatoxin B1, aflatoxin B2, aflatoxin G1 and aflatoxin G2 using reversed-phase HPLC were carried out on 84 samples of ordinary rice grains and 83 samples of wheat flour. Two point four percent (2.4%) of ordinary rice grains were positive for aflatoxin G1 and 3.6% were positive for aflatoxin G2. All the positive samples were collected from private homes at concentrations ranging from 3.69-77.50 micrograms/kg. One point two percent (1.2%) of wheat flour samples were positive for aflatoxin B1 at a concentration of 25.62 micrograms/kg, 4.8% were positive for aflatoxin B2 at concentrations ranging from 11.25-252.50 micrograms/kg, 3.6% were positive for aflatoxin G1 at concentrations ranging from 25.00-289.38 micrograms/kg and 13.25% were positive for aflatoxin G2 at concentrations ranging from 16.25-436.25 micrograms/kg. Similarly, positive wheat flour samples were mostly collected from private homes.

The Comparison of Detrital Zircon Ages to Point Count Provenance Analysis for the Pottsville Sandstone in the Northern Appalachian Foreland Basin Venango County, Pennsylvania

NASA Astrophysics Data System (ADS)

Loveday, S.; Harris, D. B.; Schiappa, T.; Pecha, M.

2017-12-01

The specific sources of sediments deposited in the Appalachian basin prior to and immediately following the Alleghenian orogeny has long been a topic of debate. Recent advances in U-Pb dating of detrital zircons have greatly helped to determine some of the sources of these sediments. For this study, sandstone samples were collected from the Pottsville Formation in the northern Appalachian Foreland Basin, Venango County, Pennsylvania to provide supplementary data for previous work that sought to describe the provenance of the same sediments by point counts of thin sections of the same units. Results of this previous work established that the provenance for these units was transitional recycled orogenic, including multiple recycled sediments, and that a cratonic contribution was not able to be determined clearly. The previous results suggested that the paleoenvironment was a fluvial dominated delta prograding in the northern direction. However, no geochronologic data was found during this study to confirm this interpretation. We sought to verify these results by U-Pb analysis of detrital zircons. Samples were collected from the areas where the previous research took place. U-Pb ages were found from sample at the highest elevation and lowest elevation. In the first sample, sample 17SL01 (younger sample stratigraphically), the zircons yield U-Pb age range peaks at 442-468 ma and 1037-1081 ma. The probability density plot for this specific sample displays a complete age gap from 500 ma to 811 ma. In the second sample, sample 17SL03 (older rock stratigraphically), the zircons yield U-Pb ages range peaks of 424-616 ma and 975-1057 ma. This sample doesn't show any ages younger than 424 ma and it doesn't display the sample age gap as sample 17SL01 does. The ages of zircons are consistent with thin section point counting provenance results from previous research suggesting zircon transport from the northern direction.

Validation of an In Vitro Bioaccessibility Test Method for Estimation of Bioavailability of Arsenic from Soil and Sediment

DTIC Science & Technology

2012-12-01

calibrated using a certified mineral or pure metal standard and counting times are chosen to provide 3-sigma detection limits of between 100-200 ppm...also submit “blind” duplicates for analyses. The precision of the data generated by the “EMPA point count ” will be evaluated by calculating RPD values...important to consider the variation in results among all samples studied for a particular media, since the overall particle count is very large. Data

Point-of-Use Interventions to Decrease Contamination of Drinking Water: A Randomized, Controlled Pilot Study on Efficacy, Effectiveness, and Acceptability of Closed Containers, Moringa oleifera, and In-home Chlorination in Rural South India

PubMed Central

Firth, Jacqueline; Balraj, Vinohar; Muliyil, Jayaprakash; Roy, Sheela; Rani, Lilly Michael; Chandresekhar, R.; Kang, Gagandeep

2010-01-01

To assess water contamination and the relative effectiveness of three options for point-of-use water treatment in South India, we conducted a 6-month randomized, controlled intervention trial using chlorine, Moringa oleifera seeds, a closed valved container, and controls. One hundred twenty-six families participated. Approximately 70% of public drinking water sources had thermotolerant coliform counts > 100/100 mL. Neither M. oleifera seeds nor containers reduced coliform counts in water samples from participants' homes. Chlorine reduced thermotolerant coliform counts to potable levels, but was less acceptable to participants. Laboratory testing of M. oleifera seeds in water from the village confirmed the lack of reduction in coliform counts, in contrast to the improvement seen with Escherichia coli seeded distilled water. This discrepancy merits further study, as M. oleifera was effective in reducing coliform counts in other studies and compliance with Moringa use in this study was high. PMID:20439952

Point-of-use interventions to decrease contamination of drinking water: a randomized, controlled pilot study on efficacy, effectiveness, and acceptability of closed containers, Moringa oleifera, and in-home chlorination in rural South India.

PubMed

Firth, Jacqueline; Balraj, Vinohar; Muliyil, Jayaprakash; Roy, Sheela; Rani, Lilly Michael; Chandresekhar, R; Kang, Gagandeep

2010-05-01

To assess water contamination and the relative effectiveness of three options for point-of-use water treatment in South India, we conducted a 6-month randomized, controlled intervention trial using chlorine, Moringa oleifera seeds, a closed valved container, and controls. One hundred twenty-six families participated. Approximately 70% of public drinking water sources had thermotolerant coliform counts > 100/100 mL. Neither M. oleifera seeds nor containers reduced coliform counts in water samples from participants' homes. Chlorine reduced thermotolerant coliform counts to potable levels, but was less acceptable to participants. Laboratory testing of M. oleifera seeds in water from the village confirmed the lack of reduction in coliform counts, in contrast to the improvement seen with Escherichia coli seeded distilled water. This discrepancy merits further study, as M. oleifera was effective in reducing coliform counts in other studies and compliance with Moringa use in this study was high.

Better Than Counting: Density Profiles from Force Sampling

NASA Astrophysics Data System (ADS)

de las Heras, Daniel; Schmidt, Matthias

2018-05-01

Calculating one-body density profiles in equilibrium via particle-based simulation methods involves counting of events of particle occurrences at (histogram-resolved) space points. Here, we investigate an alternative method based on a histogram of the local force density. Via an exact sum rule, the density profile is obtained with a simple spatial integration. The method circumvents the inherent ideal gas fluctuations. We have tested the method in Monte Carlo, Brownian dynamics, and molecular dynamics simulations. The results carry a statistical uncertainty smaller than that of the standard counting method, reducing therefore the computation time.

Variables associated with detection probability, detection latency, and behavioral responses of Golden-winged Warblers (Vermivora chrysoptera)

USGS Publications Warehouse

Aldinger, Kyle R.; Wood, Petra B.

2015-01-01

Detection probability during point counts and its associated variables are important considerations for bird population monitoring and have implications for conservation planning by influencing population estimates. During 2008–2009, we evaluated variables hypothesized to be associated with detection probability, detection latency, and behavioral responses of male Golden-winged Warblers in pastures in the Monongahela National Forest, West Virginia, USA. This is the first study of male Golden-winged Warbler detection probability, detection latency, or behavioral response based on point-count sampling with known territory locations and identities for all males. During 3-min passive point counts, detection probability decreased as distance to a male's territory and time since sunrise increased. During 3-min point counts with playback, detection probability decreased as distance to a male's territory increased, but remained constant as time since sunrise increased. Detection probability was greater when point counts included type 2 compared with type 1 song playback, particularly during the first 2 min of type 2 song playback. Golden-winged Warblers primarily use type 1 songs (often zee bee bee bee with a higher-pitched first note) in intersexual contexts and type 2 songs (strident, rapid stutter ending with a lower-pitched buzzy note) in intrasexual contexts. Distance to a male's territory, ordinal date, and song playback type were associated with the type of behavioral response to song playback. Overall, ~2 min of type 2 song playback may increase the efficacy of point counts for monitoring populations of Golden-winged Warblers by increasing the conspicuousness of males for visual identification and offsetting the consequences of surveying later in the morning. Because playback may interfere with the ability to detect distant males, it is important to follow playback with a period of passive listening. Our results indicate that even in relatively open pasture vegetation, detection probability of male Golden-winged Warblers is imperfect and highly variable.

Estimating population trends with a linear model

USGS Publications Warehouse

Bart, Jonathan; Collins, Brian D.; Morrison, R.I.G.

2003-01-01

We describe a simple and robust method for estimating trends in population size. The method may be used with Breeding Bird Survey data, aerial surveys, point counts, or any other program of repeated surveys at permanent locations. Surveys need not be made at each location during each survey period. The method differs from most existing methods in being design based, rather than model based. The only assumptions are that the nominal sampling plan is followed and that sample size is large enough for use of the t-distribution. Simulations based on two bird data sets from natural populations showed that the point estimate produced by the linear model was essentially unbiased even when counts varied substantially and 25% of the complete data set was missing. The estimating-equation approach, often used to analyze Breeding Bird Survey data, performed similarly on one data set but had substantial bias on the second data set, in which counts were highly variable. The advantages of the linear model are its simplicity, flexibility, and that it is self-weighting. A user-friendly computer program to carry out the calculations is available from the senior author.

The application of the hazard analysis and control points (HACCP) in an ice cream production plant.

PubMed

El-Tawila, M M

1998-01-01

The HACCP system is applied in the present study as a preventive food safety approach to control some hazards appearing in one of the ice cream production plants in Egypt. The problem comprised the presence of bacteriological and some chemical contamination in most of the company products. Before applying the HACCP system, the samples examination showed high total mesophilic plat count in 50% of the samples and high coliform count in all samples compared to the level recommended in the Egyptian standards. The highest staphylococcal count (negative for coagulase test) obtained was that of chocolate (1.3 x 10(4) CFU/g) followed by mango ice cream (l.0 x 10(4) CFU/g). Faecal coliform was only positive in mango ice cream. Additionally, the levels of lead, iron and copper have been determined. Copper was higher than the recommended level in all samples and ranged between 0.46 ppm in pistachio ice cream and 2.48 ppm in chocolate ice cream. Most of the CCPs in the ice cream production were mainly due to improper handling and practices throughout the processing steps and also related to the lack of food hygiene knowledge of the workers. The application of HACCP system has successfully reduced the bacteriological hazards in all samples. After applying the corrective actions, the highest total aerobic plate count (8.0 x 10(4)) was that of Swiss chocolate ice cream which corresponds to 50% of the recommended level by the Egyptian standards. Coliform count was less than 10 in all samples except mango ice cream (43 MPN). A significant decrease in staphylococcal count, faecal coliform and trace metal contamination was also recorded in all samples.

The unbiasedness of a generalized mirage boundary correction method for Monte Carlo integration estimators of volume

Treesearch

Thomas B. Lynch; Jeffrey H. Gove

2014-01-01

The typical "double counting" application of the mirage method of boundary correction cannot be applied to sampling systems such as critical height sampling (CHS) that are based on a Monte Carlo sample of a tree (or debris) attribute because the critical height (or other random attribute) sampled from a mirage point is generally not equal to the critical...

State-space modeling of population sizes and trends in Nihoa Finch and Millerbird

USGS Publications Warehouse

Gorresen, P. Marcos; Brinck, Kevin W.; Camp, Richard J.; Farmer, Chris; Plentovich, Sheldon M.; Banko, Paul C.

2016-01-01

Both of the 2 passerines endemic to Nihoa Island, Hawai‘i, USA—the Nihoa Millerbird (Acrocephalus familiaris kingi) and Nihoa Finch (Telespiza ultima)—are listed as endangered by federal and state agencies. Their abundances have been estimated by irregularly implemented fixed-width strip-transect sampling from 1967 to 2012, from which area-based extrapolation of the raw counts produced highly variable abundance estimates for both species. To evaluate an alternative survey method and improve abundance estimates, we conducted variable-distance point-transect sampling between 2010 and 2014. We compared our results to those obtained from strip-transect samples. In addition, we applied state-space models to derive improved estimates of population size and trends from the legacy time series of strip-transect counts. Both species were fairly evenly distributed across Nihoa and occurred in all or nearly all available habitat. Population trends for Nihoa Millerbird were inconclusive because of high within-year variance. Trends for Nihoa Finch were positive, particularly since the early 1990s. Distance-based analysis of point-transect counts produced mean estimates of abundance similar to those from strip-transects but was generally more precise. However, both survey methods produced biologically unrealistic variability between years. State-space modeling of the long-term time series of abundances obtained from strip-transect counts effectively reduced uncertainty in both within- and between-year estimates of population size, and allowed short-term changes in abundance trajectories to be smoothed into a long-term trend.

Methods for measuring populations of small, diurnal forest birds.

Treesearch

D.A. Manuwal; A.B. Carey

1991-01-01

Before a bird population is measured, the objectives of the study should be clearly defined. Important factors to be considered in designing a study are study site selection, plot size or transect length, distance between sampling points, duration of counts, and frequency and timing of sampling. Qualified field personnel are especially important. Assumptions applying...

Point Counts of Birds: What Are We Estimating?

Treesearch

Douglas H. Johnson

1995-01-01

Point counts of birds are made for many reasons, including estimating local densities, determining population trends, assessing habitat preferences, and exploiting the activities of recreational birdwatchers. Problems arise unless there is a clear understanding of what point counts mean in terms of actual populations of birds. Criteria for conducting point counts...

An Exploratory Analysis of Waterfront Force Protection Measures Using Simulation

DTIC Science & Technology

2002-03-01

LEFT BLANK 75 APPENDIX B. DESIGN POINT DATA Table 16. Design Point One Data breach - count leakers- count numberAv ailablePBs- mean numberInI...0.002469 0.006237 27.63104 7144.875 0.155223 76 Table 17. Design Point Two Data breach - count leakers- count numberAv ailablePBs- mean numberInI...0.001163 4.67E-12 29.80891 6393.874 0.188209 77 Table 18. Design Point Three Data breach - count leakers- count numberAv ailablePBs- mean

An alternative method for sampling and petrographically characterizing an Eocene coal bed, southeast Kalimantan, Indonesia

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

Moore, T.A.

1990-01-01

A study undertaken on an Eocene age coal bed in southeast Kalimantan, Indonesia determined that there was a relationship between megascopically determined coal types and kinds and sizes of organic components. The study also concluded that the most efficient way to characterize the seam was from collection of two 3 cm blocks from each layer or bench defined by megascopic character and that a maximum of 125 point counts was needed on each block. Microscopic examination of uncrushed block samples showed the coal to be composed of plant parts and tissues set in a matrix of both fine-grained and amorphousmore » material. The particulate matrix is composed of cell wall and liptinite fragments, resins, spores, algae, and fungal material. The amorphous matrix consists of unstructured (at 400x) huminite and liptinite. Size measurements showed that each particulate component possessed its own size distribution which approached normality when transformed to a log{sub 2} or phi scale. Degradation of the plant material during peat accumulation probably controlled grain size in the coal types. This notion is further supported by the increased concentration of decay resistant resin and cell fillings in the nonbanded and dull coal types. In the sampling design experiment, two blocks from each layer and two layers from each coal type were collected. On each block, 2 to 4 traverses totaling 500 point counts per block were performed to test the minimum number of points needed to characterize a block. A hierarchical analysis of variance showed that most of the petrographic variation occurred between coal types. The results from these analyses also indicated that, within a coal type, sampling should concentrate on the layer level and that only 250 point counts, split between two blocks, were needed to characterize a layer.« less

Experimental analysis of the auditory detection process on avian point counts

USGS Publications Warehouse

Simons, T.R.; Alldredge, M.W.; Pollock, K.H.; Wettroth, J.M.

2007-01-01

We have developed a system for simulating the conditions of avian surveys in which birds are identified by sound. The system uses a laptop computer to control a set of amplified MP3 players placed at known locations around a survey point. The system can realistically simulate a known population of songbirds under a range of factors that affect detection probabilities. The goals of our research are to describe the sources and range of variability affecting point-count estimates and to find applications of sampling theory and methodologies that produce practical improvements in the quality of bird-census data. Initial experiments in an open field showed that, on average, observers tend to undercount birds on unlimited-radius counts, though the proportion of birds counted by individual observers ranged from 81% to 132% of the actual total. In contrast to the unlimited-radius counts, when data were truncated at a 50-m radius around the point, observers overestimated the total population by 17% to 122%. Results also illustrate how detection distances decline and identification errors increase with increasing levels of ambient noise. Overall, the proportion of birds heard by observers decreased by 28 ± 4.7% under breezy conditions, 41 ± 5.2% with the presence of additional background birds, and 42 ± 3.4% with the addition of 10 dB of white noise. These findings illustrate some of the inherent difficulties in interpreting avian abundance estimates based on auditory detections, and why estimates that do not account for variations in detection probability will not withstand critical scrutiny.

Evaluation of a clay-based acidic bedding conditioner for dairy cattle bedding.

PubMed

Proietto, R L; Hinckley, L S; Fox, L K; Andrew, S M

2013-02-01

This study investigated the effects of a clay-based acidic bedding conditioner on sawdust bedding pH, dry matter (DM), environmental pathogen counts, and environmental bacterial counts on teat ends of lactating dairy cows. Sixteen lactating Holstein cows were paired based on parity, days in milk, milk yield, and milk somatic cell count, and were negative for the presence of an intramammary pathogen. Within each pair, cows were randomly assigned to 1 of 2 treatments with 3-wk periods in a crossover design. Treatment groups consisted of 9 freestalls per group bedded with either untreated sawdust or sawdust with a clay-based acidic bedding conditioner, added at 3- to 4-d intervals over each 21-d period. Bedding and teat ends were aseptically sampled on d 0, 1, 2, 7, 14, and 21 for determination of environmental bacterial counts. At the same time points, bedding was sampled for DM and pH determination. The bacteria identified in the bedding material were total gram-negative bacteria, Streptococcus spp., and coliform bacteria. The bacteria identified on the teat ends were Streptococcus spp., coliform bacteria, and Klebsiella spp. Teat end score, milk somatic cell count, and intramammary pathogen presence were measured weekly. Bedding and teat cleanliness, environmental high and low temperatures, and dew point data were collected daily. The bedding conditioner reduced the pH, but not the DM, of the sawdust bedding compared with untreated sawdust. Overall environmental bacterial counts in bedding were lower for treated sawdust. Total bacterial counts in bedding and on teat ends increased with time over both periods. Compared with untreated sawdust, the treated bedding had lower counts of total gram-negative bacteria and streptococci, but not coliform counts. Teat end bacterial counts were lower for cows bedded on treated sawdust for streptococci, coliforms, and Klebsiella spp. compared with cows bedded on untreated sawdust. The clay-based acidic bedding conditioner reduced environmental pathogens in sawdust bedding and teat ends without affecting teat end integrity. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Pollutant loads and water quality in streams of heavily populated and industrialised towns

NASA Astrophysics Data System (ADS)

Ntengwe, F. W.

The availability of portable water is often taken for granted and water allowed to get polluted. Industries, settlements, farms, markets, leaking sewer lines, poor hygiene practices are all potential sources of pollution. Each pollutant has its own effect on water and the environment. A study was conducted in Kitwe Stream in order to establish whether engineering and other human activities affect water quality. Samples were collected at ten points, the first point being at the source while the tenth point was at the confluence with the Kafue River. The samples were analysed for physical, chemical and biological parameters. The results revealed high levels of concentration and loads of total suspended solids (TSS). The points with high TSS values were P4 (118 mg/l) and P6 (140 mg/l) representing daily loads of 7.74 and 8.71 tonnes, respectively. The highest values of coliform were found at points P9 (2099), P10 (2558) followed by P4 (1149), P5 (1256) and P6 (1370). High values of nitrites were found at points P4 (34 mg/l), P5 (32 mg/l), P6 (21 mg/l) and P10 (12.4 mg/l). Chlorides were also found to be high at points P4, P5 and P6 with values of 70 mg/l, 80 mg/l and 87 mg/l, respectively. These parameters exceeded the maximum contaminant level (MCL) of 100 mg/l for TSS, 1 mg/l for nitrites, 500/100 ml for coliform in Zambia. The conductivity and coliform were also found to be high (>500 μS/cm, >500). The benthic study revealed a normal diversity of invertebrates but chironomidae was found to be on average 60% of total species counted. The fish activity was high upstream and low downstream at the mouth of the stream where it joins the Kafue River. There was no fish activity at the middle points. The planktons (phytoplankton and zooplankton) count revealed a high count (15-30 per ml) in places where there was high fish activity and a low count (1-5 per ml) where there was no activity. The stream water quality was therefore affected by the human activities.

Super resolution imaging of HER2 gene amplification

NASA Astrophysics Data System (ADS)

Okada, Masaya; Kubo, Takuya; Masumoto, Kanako; Iwanaga, Shigeki

2016-02-01

HER2 positive breast cancer is currently examined by counting HER2 genes using fluorescence in situ hybridization (FISH)-stained breast carcinoma samples. In this research, two-dimensional super resolution fluorescence microscopy based on stochastic optical reconstruction microscopy (STORM), with a spatial resolution of approximately 20 nm in the lateral direction, was used to more precisely distinguish and count HER2 genes in a FISH-stained tissue section. Furthermore, by introducing double-helix point spread function (DH-PSF), an optical phase modulation technique, to super resolution microscopy, three-dimensional images were obtained of HER2 in a breast carcinoma sample approximately 4 μm thick.

Particle emission from artificial cometary materials

NASA Technical Reports Server (NTRS)

Koelzer, Gabriele; Kochan, Hermann; Thiel, Klaus

1992-01-01

During KOSI (comet simulation) experiments, mineral-ice mixtures are observed in simulated space conditions. Emission of ice-/dust particles from the sample surface is observed by means of different devices. The particle trajectories are recorded with a video system. In the following analysis we extracted the parameters: particle count rate, spatial distribution of starting points on the sample surface, and elevation angle and particle velocity at distances up to 5 cm from the sample surface. Different kinds of detectors are mounted on a frame in front of the sample to register the emitted particles and to collect their dust residues. By means of these instruments the particle count rates, the particle sizes and the composition of the particles can be correlated. The results are related to the gas flux density and the temperature on the sample surface during the insolation period. The particle emission is interpreted in terms of phenomena on the sample surface, e.g., formation of a dust mantle.

Density and Habitat Relationships of the Endemic White Mountain Fritillary (Boloria chariclea montinus) (Lepidoptera: Nymphalidae).

PubMed

McFarland, Kent P; Lloyd, John D; Hardy, Spencer P

2017-06-04

We conducted point counts in the alpine zone of the Presidential Range of the White Mountains, New Hampshire, USA, to estimate the distribution and density of the rare endemic White Mountain Fritillary ( Boloria chariclea montinus ). Incidence of occurrence and density of the endemic White Mountain Fritillary during surveys in 2012 and 2013 were greatest in the herbaceous-snowbank plant community. Densities at points in the heath-shrub-rush plant community were lower, but because this plant community is more widespread in the alpine zone, it likely supports the bulk of adult fritillaries. White Mountain Fritillary used cushion-tussock, the other alpine plant community suspected of providing habitat, only sparingly. Detectability of White Mountain Fritillaries varied as a consequence of weather conditions during the survey and among observers, suggesting that raw counts yield biased estimates of density and abundance. Point counts, commonly used to study and monitor populations of birds, were an effective means of sampling White Mountain Fritillary in the alpine environment where patches of habitat are small, irregularly shaped, and widely spaced, rendering line-transect methods inefficient and difficult to implement.

Compositional and Microtextural Analysis of Basaltic Feedstock Materials Used for the 2010 ISRU Field Tests, Mauna Kea, Hawaii

NASA Astrophysics Data System (ADS)

Marin, N.; Farmer, J. D.; Zacny, K.; Sellar, R. G.; Nunez, J.

2011-12-01

This study seeks to understand variations in composition and texture of basaltic pyroclastic materials used in the 2010 International Lunar Surface Operation-In-Situ Resource Utilization Analogue Test (ILSO-ISRU) held on the slopes of Mauna Kea Volcano, Hawaii (1). The quantity and quality of resources delivered by ISRU depends upon the nature of the materials processed (2). We obtained a one-meter deep auger cuttings sample of a basaltic regolith at the primary site for feed stock materials being mined for the ISRU field test. The auger sample was subdivided into six, ~16 cm depth increments and each interval was sampled and characterized in the field using the Multispectral Microscopic Imager (MMI; 3) and a portable X-ray Diffractometer (Terra, InXitu Instruments, Inc.). Splits from each sampled interval were returned to the lab and analyzed using more definitive methods, including high resolution Powder X-ray Diffraction and Thermal Infrared (TIR) spectroscopy. The mineralogy and microtexture (grain size, sorting, roundness and sphericity) of the auger samples were determined using petrographic point count measurements obtained from grain-mount thin sections. NIH Image J (http://rsb.info.nih.gov/ij/) was applied to digital images of thin sections to document changes in particle size with depth. Results from TIR showed a general predominance of volcanic glass, along with plagioclase, olivine, and clinopyroxene. In addition, thin section and XRPD analyses showed a down core increase in the abundance of hydrated iron oxides (as in situ weathering products). Quantitative point count analyses confirmed the abundance of volcanic glass in samples, but also revealed olivine and pyroxene to be minor components, that decreased in abundance with depth. Furthermore, point count and XRD analyses showed a decrease in magnetite and ilmenite with depth, accompanied by an increase in Fe3+phases, including hematite and ferrihydrite. Image J particle analysis showed that the average grain size decreased down the depth profile. This decrease in average grain size and increase in hydrated iron oxides down hole suggests that the most favorable ISRU feedstock materials were sampled in the lower half-meter of the mine section sampled.

A habitat-based point-count protocol for terrestrial birds, emphasizing Washington and Oregon.

Treesearch

Mark H. Huff; Kelly A. Bettinger; Howard L. Ferguson; Martin J. Brown; Bob. Altman

2000-01-01

We describe a protocol and provide a summary for point-count monitoring of landbirds that is designed for habitat-based objectives. Presentation is in four steps: preparation and planning, selecting monitoring sites, establishing monitoring stations, and conducting point counts. We describe the basis for doing habitat-based point counts, how they are organized, and how...

All-plastic, miniature, digital fluorescence microscope for three part white blood cell differential measurements at the point of care

PubMed Central

Forcucci, Alessandra; Pawlowski, Michal E.; Majors, Catherine; Richards-Kortum, Rebecca; Tkaczyk, Tomasz S.

2015-01-01

Three-part differential white blood cell counts are used for disease diagnosis and monitoring at the point-of-care. A low-cost, miniature achromatic microscope was fabricated for identification of lymphocytes, monocytes, and granulocytes in samples of whole blood stained with acridine orange. The microscope was manufactured using rapid prototyping techniques of diamond turning and 3D printing and is intended for use at the point-of-care in low-resource settings. The custom-designed microscope requires no manual adjustment between samples and was successfully able to classify three white blood cell types (lymphocytes, granulocytes, and monocytes) using samples of peripheral whole blood stained with acridine orange. PMID:26601006

Microbiological baseline study of poultry slaughtered in provincially inspected abattoirs in Alberta, Canada

PubMed Central

Bohaychuk, Valerie M.; Checkley, Sylvia L.; Gensler, Gary E.; Barrios, Pablo Romero

2009-01-01

Studies to determine baseline levels of microbial contaminants and foodborne bacterial pathogens are needed to evaluate the effectiveness of Hazard Analysis Critical Control Point (HACCP) programs, Good Manufacturing/Production Practices, and various interventions. In 2004 and 2005 poultry carcass rinses from provincially inspected abattoirs in Alberta, Canada, were tested to determine the levels of aerobic plate count bacteria, coliform bacteria, and generic Escherichia coli, the prevalence and levels of Campylobacter spp., and the prevalence of Salmonella spp. and Shiga toxin-producing E. coli (STEC). Samples were collected from 3 high volume and 62 low volume abbatoirs. All samples (1296) were positive for aerobic plate count bacteria, with 98.8% of samples having counts of 100 000 or less colony forming units (CFU)/cm2. Coliform bacteria were isolated from 99.7% of the 1296 carcasses and were recovered at levels of ≤ 1000 CFU/cm2 for 98.3% of the samples. Generic E. coli were recovered from 99.1% of the 1296 carcasses at levels of ≤ 1000 CFU/cm2 for 98.6% of the samples. Seventy five percent of 1234 samples that were tested for Campylobacter were positive; 37.5% of 1295 samples that were tested for Salmonella were positive; and only 2 of 1296 samples tested for STEC were positive (0.15%). PMID:19412397

Sampling Extreme Groups Invalidates Research on the Paraphilias: Implications for DSM-5 and Sex Offender Risk Assessments.

PubMed

Wollert, Richard; Cramer, Elliot

2011-01-01

Psychiatrist and Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) text editor Michael First has criticized the addition of victim counts to criteria proposed by the Paraphilia Sub-Workgroup for inclusion in DSM-5 because they will increase false-positive diagnoses. Psychologist and Chair of the DSM-5 Paraphilia Sub-Workgroup, Ray Blanchard, responded by publishing a study of pedohebephiles and teleiophiles which seemed to show that victim counts could accurately identify pedohebephiles who were selected per self-report and phallometric testing. His analysis was flawed because it did not conform to conventional clinical practice and because he sampled groups at opposite ends of the clinical spectrum. In an analysis of his full sample, we found the false-positive rate for pedohebephilia at the recommended victim count selection points was indeed very large. Why? Because data analyses that eliminate intermediate data points will generate inflated estimates of correlation coefficients, base rates, and the discriminative capacity of predictor variables. This principle is also relevant for understanding the flaws in previous research that led Hanson and Bussiere to conclude that sexual recidivism was correlated with "sexual interest in children as measured by phallometric assessment." The credibility of mental health professionals rests on the reliability of their research. Conducting, publishing, and citing research that reflects Copyright © 2011 John Wiley & Sons, Ltd.

Diversity patterns in the terrestrial avifauna of the Salton sea

Treesearch

Mark B. Mendelsohn; William I. Boarman; Robert N. Fisher

2005-01-01

We performed bird point counts monthly March-June 2001 and bi-monthly August 2001-February 2002 across a sampling grid of 35 points along the west edge of Salton Sea. We found that landbird species diversity (both in numbers of species, and numbers per species) was dependent on proximity to the sea. Diversity was at a maximum nearest the shore, and was significantly...

[Microbiological quality of the air in "small gastronomy point"].

PubMed

Wójcik-Stopczyńska, Barbara

2006-01-01

The aim of this work was the estimation of microbial contamination of the air in "small gastronomy point". The study included three places, which have been separated on the ground of their function: 1. area of subsidiaries, 2. area of distribution (sale and serving meal), 3. area of consumption. The total numbers of aerobic mesophilic bacteria, yeasts and moulds were determined by sedimentation method. Taxonomy units of fungal aerosol were also estimated. The samples of air were collected in 16 investigation points in the morning (8-8.30) and in the afternoon (14-14.30). Four series of measurements were carried out and in general 128 of air samples were tested. The results showed that numbers of bacteria, yeasts and moulds were variable and received respectively 30-3397, 0-254 and 0-138 cfu x m(-3). Microbial contamination of air changed depending on area character (the highest average count of bacteria occurred in the air of consumption area and fungi in subsidiaries area), time of a day (contamination of the air increased in the afternoon) and determination date. Only in single samples the numbers of bacteria and fungi were higher than recommended level. Pigmentary bacteria had high participation in total count of bacteria and filamentous fungi were represented mostly by Penicillium sp. and Cladosporium sp.

Quantitative basis for component factors of gas flow proportional counting efficiencies

NASA Astrophysics Data System (ADS)

Nichols, Michael C.

This dissertation investigates the counting efficiency calibration of a gas flow proportional counter with beta-particle emitters in order to (1) determine by measurements and simulation the values of the component factors of beta-particle counting efficiency for a proportional counter, (2) compare the simulation results and measured counting efficiencies, and (3) determine the uncertainty of the simulation and measurements. Monte Carlo simulation results by the MCNP5 code were compared with measured counting efficiencies as a function of sample thickness for 14C, 89Sr, 90Sr, and 90Y. The Monte Carlo model simulated strontium carbonate with areal thicknesses from 0.1 to 35 mg cm-2. The samples were precipitated as strontium carbonate with areal thicknesses from 3 to 33 mg cm-2 , mounted on membrane filters, and counted on a low background gas flow proportional counter. The estimated fractional standard deviation was 2--4% (except 6% for 14C) for efficiency measurements of the radionuclides. The Monte Carlo simulations have uncertainties estimated to be 5 to 6 percent for carbon-14 and 2.4 percent for strontium-89, strontium-90, and yttrium-90. The curves of simulated counting efficiency vs. sample areal thickness agreed within 3% of the curves of best fit drawn through the 25--49 measured points for each of the four radionuclides. Contributions from this research include development of uncertainty budgets for the analytical processes; evaluation of alternative methods for determining chemical yield critical to the measurement process; correcting a bias found in the MCNP normalization of beta spectra histogram; clarifying the interpretation of the commonly used ICRU beta-particle spectra for use by MCNP; and evaluation of instrument parameters as applied to the simulation model to obtain estimates of the counting efficiency from simulated pulse height tallies.

An assessment of the microbiological quality of liver-based pâté in England 2012-13: comparison of samples collected at retail and from catering businesses.

PubMed

McLAUCHLIN, J; Jørgensen, F; Aird, H; Charlett, A; Elviss, N; Fenelon, D; Fox, A; Willis, C; Amar, C F L

2017-06-01

The purpose of this study was to investigate the microbiological quality of liver pâté. During 2012-13, a total of 870 samples, unrelated to the investigation of food-poisoning outbreaks, were collected either at retail (46%), catering (53%) or the point of manufacture (1%) and were tested using standard methods to detect Salmonella spp. or Campylobacter spp., and to enumerate for Listeria spp., including Listeria monocytogenes, Clostridium perfringens, coagulase-positive staphylococci including Staphylococcus aureus, Bacillus spp., including Bacillus cereus, Escherichia coli, Enterobacteriaceae, and aerobic colony counts (ACCs). Seventy-three percent of samples were of satisfactory microbiological quality, 18% were borderline and 9% unsatisfactory. Salmonella spp. or Campylobacter spp. was not recovered from any sample. The most common causes of unsatisfactory results were elevated ACCs (6% of the samples) and high Enterobacteriaceae counts (4% of samples). The remaining unsatisfactory results were due to elevated counts of: E. coli (three samples); B. cereus (one sample at 2·6 × 105 cfu/g); or L. monocytogenes (one sample at 2·9 × 103 cfu/g). Pâté from retail was less likely to be contaminated with L. monocytogenes than samples collected from catering and samples from supermarkets were of significantly better microbiological quality than those from catering establishments.

Bird, mammal, and vegetation community surveys of research natural areas in the Tongass National Forest.

Treesearch

W.P. Smith; M.J. Stotts; B.A. Andres; J.M. Melton; A. Garibaldi; K. Boggs

2001-01-01

In June 1977, we surveyed seven research natural areas (RNAs) in the Tongass National Forest (Tongass). We documented the composition of biotic communities using rare plant and tidal community surveys, targeted searches for rare animals, and samples of permanent vegetation plots. Birds were sampled once along each transect with 10-minute point counts at stations 8...

7 CFR 51.628 - Tolerances.

Code of Federal Regulations, 2013 CFR

2013-01-01

... shall apply to wormy fruit. Table I—Shipping Point 1 (A) For 1 through 20 Samples Factor Grades AL 2... Grades AL 2 Number of 33-count samples 3 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40... outside the continental United States, the port of entry into the United States. 2 AL—Absolute limit...

Image subsampling and point scoring approaches for large-scale marine benthic monitoring programs

NASA Astrophysics Data System (ADS)

Perkins, Nicholas R.; Foster, Scott D.; Hill, Nicole A.; Barrett, Neville S.

2016-07-01

Benthic imagery is an effective tool for quantitative description of ecologically and economically important benthic habitats and biota. The recent development of autonomous underwater vehicles (AUVs) allows surveying of spatial scales that were previously unfeasible. However, an AUV collects a large number of images, the scoring of which is time and labour intensive. There is a need to optimise the way that subsamples of imagery are chosen and scored to gain meaningful inferences for ecological monitoring studies. We examine the trade-off between the number of images selected within transects and the number of random points scored within images on the percent cover of target biota, the typical output of such monitoring programs. We also investigate the efficacy of various image selection approaches, such as systematic or random, on the bias and precision of cover estimates. We use simulated biotas that have varying size, abundance and distributional patterns. We find that a relatively small sampling effort is required to minimise bias. An increased precision for groups that are likely to be the focus of monitoring programs is best gained through increasing the number of images sampled rather than the number of points scored within images. For rare species, sampling using point count approaches is unlikely to provide sufficient precision, and alternative sampling approaches may need to be employed. The approach by which images are selected (simple random sampling, regularly spaced etc.) had no discernible effect on mean and variance estimates, regardless of the distributional pattern of biota. Field validation of our findings is provided through Monte Carlo resampling analysis of a previously scored benthic survey from temperate waters. We show that point count sampling approaches are capable of providing relatively precise cover estimates for candidate groups that are not overly rare. The amount of sampling required, in terms of both the number of images and number of points, varies with the abundance, size and distributional pattern of target biota. Therefore, we advocate either the incorporation of prior knowledge or the use of baseline surveys to establish key properties of intended target biota in the initial stages of monitoring programs.

Precision wildlife monitoring using unmanned aerial vehicles

NASA Astrophysics Data System (ADS)

Hodgson, Jarrod C.; Baylis, Shane M.; Mott, Rowan; Herrod, Ashley; Clarke, Rohan H.

2016-03-01

Unmanned aerial vehicles (UAVs) represent a new frontier in environmental research. Their use has the potential to revolutionise the field if they prove capable of improving data quality or the ease with which data are collected beyond traditional methods. We apply UAV technology to wildlife monitoring in tropical and polar environments and demonstrate that UAV-derived counts of colony nesting birds are an order of magnitude more precise than traditional ground counts. The increased count precision afforded by UAVs, along with their ability to survey hard-to-reach populations and places, will likely drive many wildlife monitoring projects that rely on population counts to transition from traditional methods to UAV technology. Careful consideration will be required to ensure the coherence of historic data sets with new UAV-derived data and we propose a method for determining the number of duplicated (concurrent UAV and ground counts) sampling points needed to achieve data compatibility.

Hazard analysis and critical point identification at Abiss slaughter house in Alexandria.

PubMed

Gomaa, N F; El-Derea, H B; ElI-Adham, E

2003-01-01

The purpose of this study is to identify potential hazards associated with animal slaughtering and how could these affect the microbiological count of carcasses, and to describe the use of HACCP to improve the microbiological count of fresh meat. Hazards were detected by observing the different steps of animal slaughter and then filling a prepared red meat slaughterhouse score sheet. The microbiological load was determined through testing 112 swab samples taken from the surface of carcasses in addition to 21 samples from hands, knives, tap water and air. Results showed that most of the parameters of the score sheet observed for evaluating hygienic operations were classified as being of maximum risk C. The aerobic plate count enterobacteriacea, mold and yeast and staphylococci increased insignificantly after cutting to 9.7x10(2), 6.4x10, 2.6x10(2), and 3.7x10 cfu/cm2, respectively. Washing of the carcasses decreased counts insignificantly to 6.4x10(2), 2.0x10, 1.7x10(2), and 2.0x10 cfu/cm2, respectively. The microbiological count of air samples at quiet hours were lower insignificantly than those at busy hours. Subsequently a HACCP system was designed based on these microbial studies, observations of current practices within the slaughterhouse and relevant literature and following the 7 principles of HACCP.

Bacteriological quality of drinking water in Nyala, South Darfur, Sudan.

PubMed

Abdelrahman, Amira Ahmed; Eltahir, Yassir Mohammed

2011-04-01

The objective of this study was to determine the bacterial contaminations in drinking water in Nyala city, South Darfur, Sudan with special reference to the internally displaced people camps (IDPs). Two hundred and forty water samples from different sites and sources including bore holes, hand pumps, dug wells, water points, water reservoir and household storage containers were collected in 2009. The most probable number method was used to detect and count the total coliform, faecal coliform and faecal enterococci. Results revealed that the three indicators bacteria were abundant in all sources except water points. Percentages of the three indicators bacteria count above the permissible limits for drinking water in all samples were 46.4% total coliform, 45.2% faecal coliform and 25.4% faecal enterococci whereas the highest count of the indicators bacteria observed was 1,600 U/100 ml water. Enteric bacteria isolated were Escherichia coli (22.5%), Enterococcus faecalis (20.42%), Klebsiella (15.00%), Citrobacter (2.1%) and Enterobacter (3.33%). The highest contamination of water sources was observed in household storage containers (20%) followed by boreholes (11.25%), reservoirs (6.24%), hand pumps (5.42%) and dug wells (2.49%). Contamination varied from season to season with the highest level in autumn (18.33%) followed by winter (13.75%) and summer (13.32%), respectively. All sources of water in IDP camps except water points were contaminated. Data suggested the importance of greater attention for household contamination, environmental sanitation control and the raise of awareness about water contamination.

Assessment of Physicochemical and Microbiological Quality of Public Swimming Pools in Addis Ababa, Ethiopia

PubMed Central

Yedeme, Kokebe; Legese, Melese Hailu; Gonfa, Almaz; Girma, Somson

2017-01-01

Background: From swimming pools, bathers may acquire many potential pathogens or may be affected by the physicochemical characteristics of water used during bathing. Hence, this study aimed at assessing the physicochemical and microbiological quality of public swimming pools located at different hotels and recreation center in Addis Ababa, Ethiopia. Method: A cross sectional study was carried out from February to May, 2016. Nine hotels and one recreation center which recognized to have public swimming services were included. A total of 60 swimming pool water samples from 10 swimming pools were collected at deeper, shallow and intake point twice on a weekly basis using a 250 ml sterile bottle containing sodium thiosulphate. PH, residual chlorine and temperature of samples were recorded at the time of collection. Sample containing bottles were transported in ice box to microbiological laboratory and analyzed on the same day. Standard cultural and biochemical methods were used for isolation and characterization of the main microbial groups. Total viable count, total coliform count, fecal coliform count and E. coli were determined. Data was analyzed using SPSS Version 20. Results: Average PH and temperature of swimming pool water samples were 7.1 and 29oC respectively. Of all analyzed water samples, 58.4% (n=35/60) of them had PH range of 7.2-7.8, 58.3% (n=35/60) of samples had temperature in the range of 21oC-32oC and 25% (n=15/60) of water samples had residual chlorine in the range of 2-3mg/l. 73.3% (n=44/60) of the samples had a total viable count below 200 MPN/ml and 70% (n-42/60) of the samples had Total Coliform Count values less than 2 MPN/100 ml. Moreover, 66.7% (n=40/60) of the samples had fecal coliform counts falling below 1 MPN /100 ml. E. coli was absent in 70% (n=42/60) of the samples while it was present in 30% (n=18/60) of the samples. Conclusion: PH, residual chlorine and temperature value of majority of the swimming pools’ water samples were within the acceptable limit. Regarding microbial quality, most swimming pools’ water samples complied to the WHO standard. Swimming pools that did not comply to the standard both in physicochemical levels and microbial quality need improvement due to their significant health implication. PMID:28761562

Validation of acid washes as critical control points in hazard analysis and critical control point systems.

PubMed

Dormedy, E S; Brashears, M M; Cutter, C N; Burson, D E

2000-12-01

A 2% lactic acid wash used in a large meat-processing facility was validated as an effective critical control point (CCP) in a hazard analysis and critical control point (HACCP) plan. We examined the microbial profiles of beef carcasses before the acid wash, beef carcasses immediately after the acid wash, beef carcasses 24 h after the acid wash, beef subprimal cuts from the acid-washed carcasses, and on ground beef made from acid-washed carcasses. Total mesophilic, psychrotrophic, coliforms, generic Escherichia coli, lactic acid bacteria, pseudomonads, and acid-tolerant microorganisms were enumerated on all samples. The presence of Salmonella spp. was also determined. Acid washing significantly reduced all counts except for pseudomonads that were present at very low numbers before acid washing. All other counts continued to stay significantly lower (P < 0.05) than those on pre-acid-washed carcasses throughout all processing steps. Total bacteria, coliforms, and generic E. coli enumerated on ground beef samples were more than 1 log cycle lower than those reported in the U.S. Department of Agriculture Baseline data. This study suggests that acid washes may be effective CCPs in HACCP plans and can significantly reduce the total number of microorganisms present on the carcass and during further processing.

Testing the importance of auditory detections in avian point counts

USGS Publications Warehouse

Brewster, J.P.; Simons, T.R.

2009-01-01

Recent advances in the methods used to estimate detection probability during point counts suggest that the detection process is shaped by the types of cues available to observers. For example, models of the detection process based on distance-sampling or time-of-detection methods may yield different results for auditory versus visual cues because of differences in the factors that affect the transmission of these cues from a bird to an observer or differences in an observer's ability to localize cues. Previous studies suggest that auditory detections predominate in forested habitats, but it is not clear how often observers hear birds prior to detecting them visually. We hypothesized that auditory cues might be even more important than previously reported, so we conducted an experiment in a forested habitat in North Carolina that allowed us to better separate auditory and visual detections. Three teams of three observers each performed simultaneous 3-min unlimited-radius point counts at 30 points in a mixed-hardwood forest. One team member could see, but not hear birds, one could hear, but not see, and the third was nonhandicapped. Of the total number of birds detected, 2.9% were detected by deafened observers, 75.1% by blinded observers, and 78.2% by nonhandicapped observers. Detections by blinded and nonhandicapped observers were the same only 54% of the time. Our results suggest that the detection of birds in forest habitats is almost entirely by auditory cues. Because many factors affect the probability that observers will detect auditory cues, the accuracy and precision of avian point count estimates are likely lower than assumed by most field ornithologists. ?? 2009 Association of Field Ornithologists.

Patterns of forest use and endemism in resident bird communities of north-central Michoacan, Mexico

Treesearch

Santiago Garcia; Deborah M. Finch; Gilberto Chavez Leon

1998-01-01

We compared breeding avian communities among 11 habitat types in north-central Michoacan, Mexico, to determine patterns of forest use by endemic and nonendemic resident species. Point counts of birds and vegetation measurements were conducted at 124 sampling localities from May through July, in 1994 and 1995. Six native forest types sampled were pine, pine-oak, oak-...

Salmonella contamination risk points in broiler carcasses during slaughter line processing.

PubMed

Rivera-Pérez, Walter; Barquero-Calvo, Elías; Zamora-Sanabria, Rebeca

2014-12-01

Salmonella is one of the foodborne pathogens most commonly associated with poultry products. The aim of this work was to identify and analyze key sampling points creating risk of Salmonella contamination in a chicken processing plant in Costa Rica and perform a salmonellosis risk analysis. Accordingly, the following examinations were performed: (i) qualitative testing (presence or absence of Salmonella), (ii) quantitative testing (Salmonella CFU counts), and (iii) salmonellosis risk analysis, assuming consumption of contaminated meat from the processing plant selected. Salmonella was isolated in 26% of the carcasses selected, indicating 60% positive in the flocks sampled. The highest Salmonella counts were observed after bleeding (6.1 log CFU per carcass), followed by a gradual decrease during the subsequent control steps. An increase in the percentage of contamination (10 to 40%) was observed during evisceration and spray washing (after evisceration), with Salmonella counts increasing from 3.9 to 5.1 log CFU per carcass. According to the prevalence of Salmonella -contaminated carcasses released to trade (20%), we estimated a risk of 272 cases of salmonellosis per year as a result of the consumption of contaminated chicken. Our study suggests that the processes of evisceration and spray washing represent a risk of Salmonella cross-contamination and/ or recontamination in broilers during slaughter line processing.

Antimicrobial effects of root canal medicaments against Enterococcus faecalis and Streptococcus mutans.

PubMed

Atila-Pektaş, B; Yurdakul, P; Gülmez, D; Görduysus, O

2013-05-01

To compare the antimicrobial activities of Activ Point (Roeko, Langenau, Germany), Calcium Hydroxide Plus Point (Roeko, Langenau, Germany), calcium hydroxide, 1% chlorhexidine gel and bioactive glass (S53P4) against Enterococcus faecalis and Streptococcus mutans. One hundred and twenty extracted single-rooted human teeth were used. After removing the crowns, root canals were prepared by using the Protaper rotary system. Following autoclave sterilization, root canals were incubated at 37 °C with E. faecalis ATCC 29212 and S. mutans RSHM 676 for 1 week. The specimens, which were divided into five treatment groups for each microorganism according to the intracanal medicament used, were tested in 10 experimental runs. In each experimental run, 10 roots were included as treatment, one root as positive control and one root as sterility control. Sterile paper points were utilized to take samples from root canals after the incubation of teeth in thioglycollate medium at 37 °C for 1 week. Samples taken from teeth by sterile paper points were inoculated onto sheep blood agar, and following an overnight incubation, the colonies grown on sheep blood agar were counted and interpreted as colony-forming units. Results were tested statistically by using Kruskal-Wallis and Conover's nonparametric multiple comparison tests. CHX gel (P < 0.001 and P < 0.001), Activ Point (P = 0.003 and P = 0.002) and Ca(OH)₂ (P = 0.010 and P = 0.005) were significantly more effective against E. faecalis than that of Ca(OH)₂ Plus Point and bioactive glass, respectively. On the other hand, compared with Ca(OH)₂ , CHX gel (P < 0.001), and Activ Point (P < 0.001), bioactive glass (P = 0.014) produced significantly lower colony counts of S. mutans. When compared with the positive control, treatment with Ca(OH)₂ Plus Point (P = 0.085 and P = 0.066) did not produce significantly lower colony counts of E. faecalis and S. mutans, respectively. Compared with the medicaments having an antimicrobial effect because of their alkaline pH, the medicaments containing chlorhexidine were effective against both E. faecalis and S. mutans. © 2012 International Endodontic Journal.

Evaluation of hepatic steatosis in dogs with congenital portosystemic shunts using Oil Red O staining.

PubMed

Hunt, G B; Luff, J A; Daniel, L; Van den Bergh, R

2013-11-01

The aims of this prospective study were to quantify steatosis in dogs with congenital portosystemic shunts (CPS) using a fat-specific stain, to compare the amount of steatosis in different lobes of the liver, and to evaluate intra- and interobserver variability in lipid point counting. Computer-assisted point counting of lipid droplets was undertaken following Oil Red O staining in 21 dogs with congenital portosystemic shunts and 9 control dogs. Dogs with congenital portosystemic shunts had significantly more small lipid droplets (<6 μ) than control dogs (P = .0013 and .0002, respectively). There was no significant difference in steatosis between liver lobes for either control dogs and CPS dogs. Significant differences were seen between observers for the number of large lipid droplets (>9 μ) and lipogranulomas per tissue point (P = .023 and .01, respectively). In conclusion, computer-assisted counting of lipid droplets following Oil Red O staining of liver biopsy samples allows objective measurement and detection of significant differences between dogs with CPS and normal dogs. This method will allow future evaluation of the relationship between different presentations of CPS (anatomy, age, breed) and lipidosis, as well as the impact of hepatic lipidosis on outcomes following surgical shunt attenuation.

Microbial air quality and bacterial surface contamination in ambulances during patient services.

PubMed

Luksamijarulkul, Pipat; Pipitsangjan, Sirikun

2015-03-01

We sought to assess microbial air quality and bacterial surface contamination on medical instruments and the surrounding areas among 30 ambulance runs during service. We performed a cross-sectional study of 106 air samples collected from 30 ambulances before patient services and 212 air samples collected during patient services to assess the bacterial and fungal counts at the two time points. Additionally, 226 surface swab samples were collected from medical instrument surfaces and the surrounding areas before and after ambulance runs. Groups or genus of isolated bacteria and fungi were preliminarily identified by Gram's stain and lactophenol cotton blue. Data were analyzed using descriptive statistics, t-test, and Pearson's correlation coefficient with a p-value of less than 0.050 considered significant. The mean and standard deviation of bacterial and fungal counts at the start of ambulance runs were 318±485cfu/m(3) and 522±581cfu/m(3), respectively. Bacterial counts during patient services were 468±607cfu/m(3) and fungal counts were 656±612cfu/m(3). Mean bacterial and fungal counts during patient services were significantly higher than those at the start of ambulance runs, p=0.005 and p=0.030, respectively. For surface contamination, the overall bacterial counts before and after patient services were 0.8±0.7cfu/cm(2) and 1.3±1.1cfu/cm(2), respectively (p<0.001). The predominant isolated bacteria and fungi were Staphylococcus spp. and Aspergillus spp., respectively. Additionally, there was a significantly positive correlation between bacterial (r=0.3, p<0.010) and fungal counts (r=0.2, p=0.020) in air samples and bacterial counts on medical instruments and allocated areas. This study revealed high microbial contamination (bacterial and fungal) in ambulance air during services and higher bacterial contamination on medical instrument surfaces and allocated areas after ambulance services compared to the start of ambulance runs. Additionally, bacterial and fungal counts in ambulance air showed a significantly positive correlation with the bacterial surface contamination on medical instruments and allocated areas. Further studies should be conducted to determine the optimal intervention to reduce microbial contamination in the ambulance environment.

Evaluating point count efficiency relative to territory mapping in cropland birds

Treesearch

Andre Cyr; Denis Lepage; Kathryn Freemark

1995-01-01

Species richness, composition, and abundance of farmland birds were compared between point counts (50-m, 100-m, and 150-m radius half circles) and territory mapping on three 40-ha plots in Québec, Canada. Point counts of smaller radii tended to have larger density estimates than counts of larger radii. Territory mapping detected 10 species more than 150-m...

Can Detectability Analysis Improve the Utility of Point Counts for Temperate Forest Raptors?

EPA Science Inventory

Temperate forest breeding raptors are poorly represented in typical point count surveys because these birds are cryptic and typically breed at low densities. In recent years, many new methods for estimating detectability during point counts have been developed, including distanc...

Conditional analysis of mixed Poisson processes with baseline counts: implications for trial design and analysis.

PubMed

Cook, Richard J; Wei, Wei

2003-07-01

The design of clinical trials is typically based on marginal comparisons of a primary response under two or more treatments. The considerable gains in efficiency afforded by models conditional on one or more baseline responses has been extensively studied for Gaussian models. The purpose of this article is to present methods for the design and analysis of clinical trials in which the response is a count or a point process, and a corresponding baseline count is available prior to randomization. The methods are based on a conditional negative binomial model for the response given the baseline count and can be used to examine the effect of introducing selection criteria on power and sample size requirements. We show that designs based on this approach are more efficient than those proposed by McMahon et al. (1994).

RnaSeqSampleSize: real data based sample size estimation for RNA sequencing.

PubMed

Zhao, Shilin; Li, Chung-I; Guo, Yan; Sheng, Quanhu; Shyr, Yu

2018-05-30

One of the most important and often neglected components of a successful RNA sequencing (RNA-Seq) experiment is sample size estimation. A few negative binomial model-based methods have been developed to estimate sample size based on the parameters of a single gene. However, thousands of genes are quantified and tested for differential expression simultaneously in RNA-Seq experiments. Thus, additional issues should be carefully addressed, including the false discovery rate for multiple statistic tests, widely distributed read counts and dispersions for different genes. To solve these issues, we developed a sample size and power estimation method named RnaSeqSampleSize, based on the distributions of gene average read counts and dispersions estimated from real RNA-seq data. Datasets from previous, similar experiments such as the Cancer Genome Atlas (TCGA) can be used as a point of reference. Read counts and their dispersions were estimated from the reference's distribution; using that information, we estimated and summarized the power and sample size. RnaSeqSampleSize is implemented in R language and can be installed from Bioconductor website. A user friendly web graphic interface is provided at http://cqs.mc.vanderbilt.edu/shiny/RnaSeqSampleSize/ . RnaSeqSampleSize provides a convenient and powerful way for power and sample size estimation for an RNAseq experiment. It is also equipped with several unique features, including estimation for interested genes or pathway, power curve visualization, and parameter optimization.

Temporal differences in point counts of bottomland forest landbirds

USGS Publications Warehouse

Smith, W.P.; Twedt, D.J.

1999-01-01

We compared number of avian species and individuals in morning and evening point counts during the breeding season and during winter in a bottomland hardwood forest in west-central Mississippi. USA. In both seasons, more species and individuals were recorded during morning counts than during evening counts. We also compared morning and evening detections for 18 species during the breeding season and 9 species during winter. Blue Jay (Cyanocitta cristata), Mourning Dove (Zenaida macroura), and Red-bellied Woodpecker (Melanerpes carolinus) were detected significantly more often in morning counts than in evening counts during the breeding season. Tufted Titmouse (Baeolophus bicolor) was recorded more often in morning Counts than evening counts during the breeding season and during winter. No species was detected more often in evening counts. Thus, evening point counts of birds during either the breeding season or winter will likely underestimate species richness, overall avian abundance, and the abundance of some individual species in bottomland hardwood forests.

CINAHL and MEDLINE: a comparison of indexing practices.

PubMed

Brenner, S H; McKinin, E J

1989-10-01

A random sample of fifty nursing articles indexed in both MEDLINE and CINAHL (NURSING & ALLIED HEALTH) during 1986 was used for comparing indexing practices. Indexing was analyzed by counting the number of major descriptors, the number of major and minor descriptors, the number of indexing access points, the number of common indexing access points, and the number and type of unique indexing access points. The study results indicate: there are few differences in the number of major descriptors used, MEDLINE uses almost twice as many descriptors, MEDLINE has almost twice as many indexing access points, and MEDLINE and CINAHL provide few common access points.

CINAHL and MEDLINE: a comparison of indexing practices.

PubMed Central

Brenner, S H; McKinin, E J

1989-01-01

A random sample of fifty nursing articles indexed in both MEDLINE and CINAHL (NURSING & ALLIED HEALTH) during 1986 was used for comparing indexing practices. Indexing was analyzed by counting the number of major descriptors, the number of major and minor descriptors, the number of indexing access points, the number of common indexing access points, and the number and type of unique indexing access points. The study results indicate: there are few differences in the number of major descriptors used, MEDLINE uses almost twice as many descriptors, MEDLINE has almost twice as many indexing access points, and MEDLINE and CINAHL provide few common access points. PMID:2676049

Analysis system for characterisation of simple, low-cost microfluidic components

NASA Astrophysics Data System (ADS)

Smith, Suzanne; Naidoo, Thegaran; Nxumalo, Zandile; Land, Kevin; Davies, Emlyn; Fourie, Louis; Marais, Philip; Roux, Pieter

2014-06-01

There is an inherent trade-off between cost and operational integrity of microfluidic components, especially when intended for use in point-of-care devices. We present an analysis system developed to characterise microfluidic components for performing blood cell counting, enabling the balance between function and cost to be established quantitatively. Microfluidic components for sample and reagent introduction, mixing and dispensing of fluids were investigated. A simple inlet port plugging mechanism is used to introduce and dispense a sample of blood, while a reagent is released into the microfluidic system through compression and bursting of a blister pack. Mixing and dispensing of the sample and reagent are facilitated via air actuation. For these microfluidic components to be implemented successfully, a number of aspects need to be characterised for development of an integrated point-of-care device design. The functional components were measured using a microfluidic component analysis system established in-house. Experiments were carried out to determine: 1. the force and speed requirements for sample inlet port plugging and blister pack compression and release using two linear actuators and load cells for plugging the inlet port, compressing the blister pack, and subsequently measuring the resulting forces exerted, 2. the accuracy and repeatability of total volumes of sample and reagent dispensed, and 3. the degree of mixing and dispensing uniformity of the sample and reagent for cell counting analysis. A programmable syringe pump was used for air actuation to facilitate mixing and dispensing of the sample and reagent. Two high speed cameras formed part of the analysis system and allowed for visualisation of the fluidic operations within the microfluidic device. Additional quantitative measures such as microscopy were also used to assess mixing and dilution accuracy, as well as uniformity of fluid dispensing - all of which are important requirements towards the successful implementation of a blood cell counting system.

Possible association of Bifidobacterium and Lactobacillus in the gut microbiota of patients with major depressive disorder.

PubMed

Aizawa, Emiko; Tsuji, Hirokazu; Asahara, Takashi; Takahashi, Takuya; Teraishi, Toshiya; Yoshida, Sumiko; Ota, Miho; Koga, Norie; Hattori, Kotaro; Kunugi, Hiroshi

2016-09-15

Bifidobacterium and Lactobacillus in the gut have been suggested to have a beneficial effect on stress response and depressive disorder. We examined whether these bacterial counts are reduced in patients with major depressive disorder (MDD) than in healthy controls. Bifidobacterium and Lactobacillus counts in fecal samples were estimated in 43 patients and 57 controls using bacterial rRNA-targeted reverse transcription-quantitative polymerase chain reaction The patients had significantly lower Bifidobacterium counts (P=0.012) and tended to have lower Lactobacillus counts (P=0.067) than the controls. Individuals whose bacterial counts below the optimal cut-off point (9.53 and 6.49log10 cells/g for Bifidobacterium and Lactobacillus, respectively) were significantly more common in the patients than in the controls for both bacteria (Bifidobacterium: odds ratio 3.23, 95% confidence interval [CI] 1.38-7.54, P=0.010; Lactobacillus: 2.57, 95% CI 1.14-5.78, P=0.027). Using the same cut-off points, we observed an association between the bacterial counts and Irritable bowel syndrome. Frequency of fermented milk consumption was associated with higher Bifidobacterium counts in the patients. The findings should be interpreted with caution since effects of gender and diet were not fully taken into account in the analysis. Our results provide direct evidence, for the first time, that individuals with lower Bifidobacterium and/or Lactobacillus counts are more common in patients with MDD compared to controls. Our findings provide new insight into the pathophysiology of MDD and will enhance future research on the use of pro- and prebiotics in the treatment of MDD. Copyright © 2016 Elsevier B.V. All rights reserved.

A removal model for estimating detection probabilities from point-count surveys

USGS Publications Warehouse

Farnsworth, G.L.; Pollock, K.H.; Nichols, J.D.; Simons, T.R.; Hines, J.E.; Sauer, J.R.

2002-01-01

Use of point-count surveys is a popular method for collecting data on abundance and distribution of birds. However, analyses of such data often ignore potential differences in detection probability. We adapted a removal model to directly estimate detection probability during point-count surveys. The model assumes that singing frequency is a major factor influencing probability of detection when birds are surveyed using point counts. This may be appropriate for surveys in which most detections are by sound. The model requires counts to be divided into several time intervals. Point counts are often conducted for 10 min, where the number of birds recorded is divided into those first observed in the first 3 min, the subsequent 2 min, and the last 5 min. We developed a maximum-likelihood estimator for the detectability of birds recorded during counts divided into those intervals. This technique can easily be adapted to point counts divided into intervals of any length. We applied this method to unlimited-radius counts conducted in Great Smoky Mountains National Park. We used model selection criteria to identify whether detection probabilities varied among species, throughout the morning, throughout the season, and among different observers. We found differences in detection probability among species. Species that sing frequently such as Winter Wren (Troglodytes troglodytes) and Acadian Flycatcher (Empidonax virescens) had high detection probabilities (∼90%) and species that call infrequently such as Pileated Woodpecker (Dryocopus pileatus) had low detection probability (36%). We also found detection probabilities varied with the time of day for some species (e.g. thrushes) and between observers for other species. We used the same approach to estimate detection probability and density for a subset of the observations with limited-radius point counts.

Point count length and detection of forest neotropical migrant birds

USGS Publications Warehouse

Dawson, D.K.; Smith, D.R.; Robbins, C.S.; Ralph, C. John; Sauer, John R.; Droege, Sam

1995-01-01

Comparisons of bird abundances among years or among habitats assume that the rates at which birds are detected and counted are constant within species. We use point count data collected in forests of the Mid-Atlantic states to estimate detection probabilities for Neotropical migrant bird species as a function of count length. For some species, significant differences existed among years or observers in both the probability of detecting the species and in the rate at which individuals are counted. We demonstrate the consequence that variability in species' detection probabilities can have on estimates of population change, and discuss ways for reducing this source of bias in point count studies.

Raman Spectroscopy for Mineral Identification and Quantification for in situ Planetary Surface Analysis: A Point Count Method

NASA Technical Reports Server (NTRS)

Haskin, Larry A.; Wang, Alian; Rockow, Kaylynn M.; Jolliff, Bradley L.; Korotev, Randy L.; Viskupic, Karen M.

1997-01-01

Quantification of mineral proportions in rocks and soils by Raman spectroscopy on a planetary surface is best done by taking many narrow-beam spectra from different locations on the rock or soil, with each spectrum yielding peaks from only one or two minerals. The proportion of each mineral in the rock or soil can then be determined from the fraction of the spectra that contain its peaks, in analogy with the standard petrographic technique of point counting. The method can also be used for nondestructive laboratory characterization of rock samples. Although Raman peaks for different minerals seldom overlap each other, it is impractical to obtain proportions of constituent minerals by Raman spectroscopy through analysis of peak intensities in a spectrum obtained by broad-beam sensing of a representative area of the target material. That is because the Raman signal strength produced by a mineral in a rock or soil is not related in a simple way through the Raman scattering cross section of that mineral to its proportion in the rock, and the signal-to-noise ratio of a Raman spectrum is poor when a sample is stimulated by a low-power laser beam of broad diameter. Results obtained by the Raman point-count method are demonstrated for a lunar thin section (14161,7062) and a rock fragment (15273,7039). Major minerals (plagioclase and pyroxene), minor minerals (cristobalite and K-feldspar), and accessory minerals (whitlockite, apatite, and baddeleyite) were easily identified. Identification of the rock types, KREEP basalt or melt rock, from the 100-location spectra was straightforward.

Influence of Point Count Length and Repeated Visits on Habitat Model Performance

Treesearch

Randy Dettmers; David A. Buehler; John G. Bartlett; Nathan A. Klaus

1999-01-01

Point counts are commonly used to monitor bird populations, and a substantial amount of research has investigated how conducting counts for different lengths of time affects the accuracy of these counts and the subsequent ability to monitor changes in population trends. However, little work has been done io assess how changes in count duration affect bird-habitat...

Optimizing the duration of point counts for monitoring trends in bird populations

Treesearch

Jared Verner

1988-01-01

Minute-by-minute analysis of point counts of birds in mixed-conifer forests in the Sierra National Forest, central California, showed that cumulative counts of species and individuals increased in a curvilinear fashion but did not reach asymptotes after 10 minutes of counting. Comparison of the expected number of individuals counted per hour with various combinations...

Potential effects of groundwater and surface water contamination in an urban area, Qus City, Upper Egypt

NASA Astrophysics Data System (ADS)

Abdalla, Fathy; Khalil, Ramadan

2018-05-01

The potential effects of anthropogenic activities, in particular, unsafe sewage disposal practices, on shallow groundwater in an unconfined aquifer and on surface water were evaluated within an urban area by the use of hydrogeological, hydrochemical, and bacteriological analyses. Physicochemical and bacteriological data was obtained from forty-five sampling points based on33 groundwater samples from variable depths and 12 surface water samples. The pollution sources are related to raw sewage and wastewater discharges, agricultural runoff, and wastewater from the nearby Paper Factory. Out of the 33 groundwater samples studied, 17 had significant concentrations of NO3-, Cl- and SO42-, and high bacteria counts. Most of the water samples from the wells contained high Fe, Mn, Pb, Zn, Cd, and Cr. The majority of surface water samples presented high NO3- concentrations and high bacteria counts. A scatter plot of HCO3- versus Ca indicates that 58% of the surface water samples fall within the extreme contamination zone, while the others are within the mixing zone; whereas 94% of groundwater samples showed evidence of mixing between groundwater and wastewater. The bacteriological assessment showed that all measured surface and groundwater samples contained Escherichia coli and total coliform bacteria. A risk map delineated four classes of contamination, namely, those sampling points with high (39.3%), moderate (36.3%), low (13.3%), and very low (11.1%) levels of contamination. Most of the highest pollution points were in the middle part of the urban area, which suffers from unmanaged sewage and industrial effluents. Overall, the results demonstrate that surface and groundwater in Qus City are at high risk of contamination by wastewater since the water table is shallow and there is a lack of a formal sanitation network infrastructure. The product risk map is a useful tool for prioritizing zones that require immediate mitigation and monitoring.

Marsh birds and the North American Breeding Bird Survey: judging the value of a landscape level survey for habitat specialist species with low detection rates

USGS Publications Warehouse

Sauer, J.R.

1999-01-01

The North American Breeding Bird Survey was started in 1966, and provides information on population change for >400 species of birds. it covers the continental United States, Canada, and Alaska, and is conducted once each year, in June, by volunteer observers. A 39.4 kIn roadside survey route is driven starting 30 min before sunrise, and a 3 min point count is conducted at each of 50 stops spaced every 0.8 kIn. Existing analyses of the data are internet-based (http://www.mbr-pwrc.usgs.govlbbslbbs.html), and include maps of relative abundance, estimates of population change including trends (%/yr), composite annual indices (pattern in time), and maps of population trend (pattern in space). At least 36 species of marsh birds are encountered on the BBS, and the survey provides estimates with greatly varying levels of efficiency for the species. It is often difficult to understand how well the BBS surveys a species. Often, efficiency is judged by estimating trend and its variance for a species, then by calculating power and needed samples to detect a prespecified trend over some time period (e.g., a 2%/yr trend over 31 yr). Unfortunately, this approach is not always valid, as estimated trends and variances can be of little use if the population is poorly sampled. Lurking concerns with BBS data include (1) incomplete coverage of species range; (2) undersampling of habitats; and (3) low and variable visibility of birds during point counts. It is difficult to evaluate these concerns, because known populations do not exist for comparison with counts, and detection rates are time-consuming and costly to estimate. I evaluated the efficiency of the BBS for selected rails (Rallidae) and snipes (Scolopacidae), presenting estimates of population trend over 1966-1996 (T), power to detect 2%/yr trend over 31 yr, needed samples to achieve power of 0.75 with alpha= 0.1, number of survey routes with data for the species (N), average abundance on survey routes (RA), and maps of relative abundance. Examples include Yellow Rail (Coturnicops noveboracensis) (T=12 %/yr; P= 0.0085; N =28; routes; RA=0.05; Power=0.37; Needed samples=85), Black Rail (Laterallus jamaicensis) (No trend data or power information available, N =8), Clapper Rail (Rallus longirostris) (T=1.9%/yr; P=0.55; N =64; RA=0.31; Power=0.35; Needed samples=590), King Rail (Rallus elegans) (T=-4.2 %/yr; P= 0.03; N =76; Power=0.41; Needed samples=159), Sora (Porzana carolina) (T=0.98 %/yr; P= 0.24; N =720; RA= 0.92; Power=0.69; Needed samples= 377), and Common Snipe (Gallinago gallinago) (T=-0.24 %/yr; P= 0.54; N =1412; RA= 2.19; Power=0.98; Needed samples=205). With regard to quality of BBS data, marsh birds fall into 3 categories: (1) almost never encountered on BBS routes; (2) encountered at extremely low abundances on BBS routes; and (3) probably fairly well sampled by BBS roadside counts. BBS data can provide useful information for many marsh bird species, but users should be aware of the limitations of the BBS sample for monitoring species that have low visibility from point counts and prefer habitats not often encountered on roadsides.

Abdominal fat volume estimation by stereology on CT: a comparison with manual planimetry.

PubMed

Manios, G E; Mazonakis, M; Voulgaris, C; Karantanas, A; Damilakis, J

2016-03-01

To deploy and evaluate a stereological point-counting technique on abdominal CT for the estimation of visceral (VAF) and subcutaneous abdominal fat (SAF) volumes. Stereological volume estimations based on point counting and systematic sampling were performed on images from 14 consecutive patients who had undergone abdominal CT. For the optimization of the method, five sampling intensities in combination with 100 and 200 points were tested. The optimum stereological measurements were compared with VAF and SAF volumes derived by the standard technique of manual planimetry on the same scans. Optimization analysis showed that the selection of 200 points along with the sampling intensity 1/8 provided efficient volume estimations in less than 4 min for VAF and SAF together. The optimized stereology showed strong correlation with planimetry (VAF: r = 0.98; SAF: r = 0.98). No statistical differences were found between the two methods (VAF: P = 0.81; SAF: P = 0.83). The 95% limits of agreement were also acceptable (VAF: -16.5%, 16.1%; SAF: -10.8%, 10.7%) and the repeatability of stereology was good (VAF: CV = 4.5%, SAF: CV = 3.2%). Stereology may be successfully applied to CT images for the efficient estimation of abdominal fat volume and may constitute a good alternative to the conventional planimetric technique. Abdominal obesity is associated with increased risk of disease and mortality. Stereology may quantify visceral and subcutaneous abdominal fat accurately and consistently. The application of stereology to estimating abdominal volume fat reduces processing time. Stereology is an efficient alternative method for estimating abdominal fat volume.

Molecular analyses of two bacterial sampling methods in ligature-induced periodontitis in rats.

PubMed

Fontana, Carla Raquel; Grecco, Clovis; Bagnato, Vanderlei Salvador; de Freitas, Laura Marise; Boussios, Constantinos I; Soukos, Nikolaos S

2018-02-01

The prevalence profile of periodontal pathogens in dental plaque can vary as a function of the detection method; however, the sampling technique may also play a role in determining dental plaque microbial profiles. We sought to determine the bacterial composition comparing two sampling methods, one well stablished and a new one proposed here. In this study, a ligature-induced periodontitis model was used in 30 rats. Twenty-seven days later, ligatures were removed and microbiological samples were obtained directly from the ligatures as well as from the periodontal pockets using absorbent paper points. Microbial analysis was performed using DNA probes to a panel of 40 periodontal species in the checkerboard assay. The bacterial composition patterns were similar for both sampling methods. However, detection levels for all species were markedly higher for ligatures compared with paper points. Ligature samples provided more bacterial counts than paper points, suggesting that the technique for induction of periodontitis could also be applied for sampling in rats. Our findings may be helpful in designing studies of induced periodontal disease-associated microbiota.

Monitoring bird populations by point counts

Treesearch

C. John Ralph; John R. Sauer; Sam Droege

1995-01-01

This volume contains in part papers presented at the Symposium on Monitoring Bird Population Trends by Point Counts, which was held November 6-7, 1991, in Beltsville, Md., in response to the need for standardization of methods to monitor bird populations by point counts. Data from various investigators working under a wide variety of conditions are presented, and...

Automated SEM Modal Analysis Applied to the Diogenites

NASA Technical Reports Server (NTRS)

Bowman, L. E.; Spilde, M. N.; Papike, James J.

1996-01-01

Analysis of volume proportions of minerals, or modal analysis, is routinely accomplished by point counting on an optical microscope, but the process, particularly on brecciated samples such as the diogenite meteorites, is tedious and prone to error by misidentification of very small fragments, which may make up a significant volume of the sample. Precise volume percentage data can be gathered on a scanning electron microscope (SEM) utilizing digital imaging and an energy dispersive spectrometer (EDS). This form of automated phase analysis reduces error, and at the same time provides more information than could be gathered using simple point counting alone, such as particle morphology statistics and chemical analyses. We have previously studied major, minor, and trace-element chemistry of orthopyroxene from a suite of diogenites. This abstract describes the method applied to determine the modes on this same suite of meteorites and the results of that research. The modal abundances thus determined add additional information on the petrogenesis of the diogenites. In addition, low-abundance phases such as spinels were located for further analysis by this method.

Evaluation of hepatic steatosis in dogs with congenital portosystemic shunts using Oil-Red-O staining

PubMed Central

Hunt, GB; Luff, J; Daniel, L; Van den Bergh, R.

2015-01-01

The aims of this prospective study were to quantify steatosis in dogs with congenital portosystemic shunts using a fat-specific stain, to compare the amount of steatosis in different lobes of the liver, and to evaluate intra- and inter-Observer variability in lipid point counting. Computer-assisted point counting of lipid droplets was undertaken following Oil-Red-O staining in 21 dogs with congenital portosystemic shunts and 9 control dogs. Dogs with congenital portosystemic shunts had significantly more small lipid droplets (< 6 μ) than control dogs (p = 0.0013 and 0.0002, respectively). There was no significant difference in steatosis between liver lobes for either control dogs and CPS dogs. Significant differences were seen between observers for the number of large lipid droplets (> 9 μ) and lipogranulomas per tissue point (p = 0.023 and 0.01, respectively). In conclusion, computer-assisted counting of lipid droplets following Oil Red O staining of liver biopsy samples allows objective measurement and detection of significant differences between dogs with CPS and normal dogs. This method will allow future evaluation of the relationship between different presentations of CPS (anatomy, age, breed) and lipidosis, as well as the impact of hepatic lipidosis on outcomes following surgical shunt attenuation. PMID:23528942

A Comparison of Bird Detection Rates Derived from On-Road vs. Off-Road Point Counts in Northern Montana

Treesearch

Richard L. Hutto; Sallie J. Hejl; Jeffrey F. Kelly; Sandra M. Pletschet

1995-01-01

We conducted a series of 275 paired (on- and off-road) point counts within 4 distinct vegetation cover types in northwestern Montana. Roadside counts generated a bird list that was essentially the same as the list generated from off-road counts within the same vegetation cover type. Species that were restricted to either on- or off-road counts were rare, suggesting...

Point Count Length and Detection of Forest Neotropical Migrant Birds

Treesearch

Deanna K. Dawson; David R. Smith; Chandler S. Robbins

1995-01-01

Comparisons of bird abundances among years or among habitats assume that the rates at which birds are detected and counted are constant within species. We use point count data collected in forests of the Mid-Atlantic states to estimate detection probabilities for Neotropical migrant bird species as a function of count length. For some species, significant differences...

Microbial Air Quality and Bacterial Surface Contamination in Ambulances During Patient Services

PubMed Central

Luksamijarulkul, Pipat; Pipitsangjan, Sirikun

2015-01-01

Objectives We sought to assess microbial air quality and bacterial surface contamination on medical instruments and the surrounding areas among 30 ambulance runs during service. Methods We performed a cross-sectional study of 106 air samples collected from 30 ambulances before patient services and 212 air samples collected during patient services to assess the bacterial and fungal counts at the two time points. Additionally, 226 surface swab samples were collected from medical instrument surfaces and the surrounding areas before and after ambulance runs. Groups or genus of isolated bacteria and fungi were preliminarily identified by Gram’s stain and lactophenol cotton blue. Data were analyzed using descriptive statistics, t-test, and Pearson’s correlation coefficient with a p-value of less than 0.050 considered significant. Results The mean and standard deviation of bacterial and fungal counts at the start of ambulance runs were 318±485cfu/m3 and 522±581cfu/m3, respectively. Bacterial counts during patient services were 468±607cfu/m3 and fungal counts were 656±612cfu/m3. Mean bacterial and fungal counts during patient services were significantly higher than those at the start of ambulance runs, p=0.005 and p=0.030, respectively. For surface contamination, the overall bacterial counts before and after patient services were 0.8±0.7cfu/cm2 and 1.3±1.1cfu/cm2, respectively (p<0.001). The predominant isolated bacteria and fungi were Staphylococcus spp. and Aspergillus spp., respectively. Additionally, there was a significantly positive correlation between bacterial (r=0.3, p<0.010) and fungal counts (r=0.2, p=0.020) in air samples and bacterial counts on medical instruments and allocated areas. Conclusions This study revealed high microbial contamination (bacterial and fungal) in ambulance air during services and higher bacterial contamination on medical instrument surfaces and allocated areas after ambulance services compared to the start of ambulance runs. Additionally, bacterial and fungal counts in ambulance air showed a significantly positive correlation with the bacterial surface contamination on medical instruments and allocated areas. Further studies should be conducted to determine the optimal intervention to reduce microbial contamination in the ambulance environment. PMID:25960835

Reviving common standards in point-count surveys for broad inference across studies

Treesearch

Steven M. Matsuoka; C. Lisa Mahon; Colleen M. Handel; Péter Sólymos; Erin M. Bayne; Patricia C. Fontaine; C. John Ralph

2014-01-01

We revisit the common standards recommended by Ralph et al. (1993, 1995a) for conducting point-count surveys to assess the relative abundance of landbirds breeding in North America. The standards originated from discussions among ornithologists in 1991 and were developed so that point-count survey data could be broadly compared and jointly analyzed by national data...

Field evaluation of distance-estimation error during wetland-dependent bird surveys

USGS Publications Warehouse

Nadeau, Christopher P.; Conway, Courtney J.

2012-01-01

Context: The most common methods to estimate detection probability during avian point-count surveys involve recording a distance between the survey point and individual birds detected during the survey period. Accurately measuring or estimating distance is an important assumption of these methods; however, this assumption is rarely tested in the context of aural avian point-count surveys. Aims: We expand on recent bird-simulation studies to document the error associated with estimating distance to calling birds in a wetland ecosystem. Methods: We used two approaches to estimate the error associated with five surveyor's distance estimates between the survey point and calling birds, and to determine the factors that affect a surveyor's ability to estimate distance. Key results: We observed biased and imprecise distance estimates when estimating distance to simulated birds in a point-count scenario (x̄error = -9 m, s.d.error = 47 m) and when estimating distances to real birds during field trials (x̄error = 39 m, s.d.error = 79 m). The amount of bias and precision in distance estimates differed among surveyors; surveyors with more training and experience were less biased and more precise when estimating distance to both real and simulated birds. Three environmental factors were important in explaining the error associated with distance estimates, including the measured distance from the bird to the surveyor, the volume of the call and the species of bird. Surveyors tended to make large overestimations to birds close to the survey point, which is an especially serious error in distance sampling. Conclusions: Our results suggest that distance-estimation error is prevalent, but surveyor training may be the easiest way to reduce distance-estimation error. Implications: The present study has demonstrated how relatively simple field trials can be used to estimate the error associated with distance estimates used to estimate detection probability during avian point-count surveys. Evaluating distance-estimation errors will allow investigators to better evaluate the accuracy of avian density and trend estimates. Moreover, investigators who evaluate distance-estimation errors could employ recently developed models to incorporate distance-estimation error into analyses. We encourage further development of such models, including the inclusion of such models into distance-analysis software.

Linkage Analysis of a Model Quantitative Trait in Humans: Finger Ridge Count Shows Significant Multivariate Linkage to 5q14.1

PubMed Central

Medland, Sarah E; Loesch, Danuta Z; Mdzewski, Bogdan; Zhu, Gu; Montgomery, Grant W; Martin, Nicholas G

2007-01-01

The finger ridge count (a measure of pattern size) is one of the most heritable complex traits studied in humans and has been considered a model human polygenic trait in quantitative genetic analysis. Here, we report the results of the first genome-wide linkage scan for finger ridge count in a sample of 2,114 offspring from 922 nuclear families. Both univariate linkage to the absolute ridge count (a sum of all the ridge counts on all ten fingers), and multivariate linkage analyses of the counts on individual fingers, were conducted. The multivariate analyses yielded significant linkage to 5q14.1 (Logarithm of odds [LOD] = 3.34, pointwise-empirical p-value = 0.00025) that was predominantly driven by linkage to the ring, index, and middle fingers. The strongest univariate linkage was to 1q42.2 (LOD = 2.04, point-wise p-value = 0.002, genome-wide p-value = 0.29). In summary, the combination of univariate and multivariate results was more informative than simple univariate analyses alone. Patterns of quantitative trait loci factor loadings consistent with developmental fields were observed, and the simple pleiotropic model underlying the absolute ridge count was not sufficient to characterize the interrelationships between the ridge counts of individual fingers. PMID:17907812

Use of total of Escherichia coli counts to assess the hygienic characteristics of a beef carcass dressing process.

PubMed

Gill, C O; McGinnis, J C; Badoni, M

1996-08-01

Swab samples were obtained from 3 sites on the surfaces of beef carcasses passing through a high speed dressing process, with 24 samples from each site being obtained at each of 4 points in the process. The aerobic microflora recovered from each swab after incubation at 25 degrees C was enumerated and characterized, and numbers of coliforms and Escherichia coli were determined. The data on aerobic flora indicated that skinning results in similar contamination of all 3 sites, that further deposition of bacteria at the brisket site occurs after skinning, and that trimming and washing achieve modest decontamination of the neck and brisket site, and extensive decontamination of the rump site. Changes in flora compositions during processing were too limited to much affect the assessment based on the aerobic flora total counts alone. The E. coli data indicated that during skinning the rump site was more heavily contaminated with faecal organisms than the other sites, that contamination of the brisket site is little altered between skinning and carcass splitting, although there is an extensive redistribution of E. coli at the neck site and sporadic, limited decontamination of the rump site, and that trimming and washing do not decontaminate the neck or rump sites, but that the rump site is extensively decontaminated by trimming. There was good correlation between E. coli and coliform counts, but weak correlation between E. coli and aerobic, 25 degrees C, counts. The findings suggest that assessments of beef carcass dressing processes for Hazard Analysis: Critical Control Point (HACCP) purposes should be based on enumerations of E. coli, or perhaps coliforms, rather than of the aerobic flora, to avoid important misunderstandings of the hygienic effects of the various operations in a process.

Consistency of mist netting and point counts in assessing landbird species richness and relative abundance during migration

Treesearch

Yong Wang; Deborah M. Finch

2002-01-01

We compared consistency of species richness and relative abundance data collected concurrently using mist netting and point counts during migration in riparian habitats along the middle Rio Grande of central New Mexico. Mist netting detected 74% and point counts detected 82% of the 197 species encountered during the study. Species that mist netting failed to capture...

Several Modified Goodness-Of-Fit Tests for the Cauchy Distribution with Unknown Scale and Location Parameters

DTIC Science & Technology

1994-03-01

labels of a, which is called significance levels. The hypothesis tests are done based on the a levels . The maximum probabilities of making type II error...critical values at specific a levels . This procedure is done for each of the 50,000 samples. The number of the samples passing each test at those specific... a levels is counted. The ratio of the number of accepted samples to 50,000 gives the percentage point. Then, subtracting that value from one would

Pre- and post-experimental manipulation assessments confirm the increase in number of birds due to the addition of nest boxes.

PubMed

Cuatianquiz Lima, Cecilia; Macías Garcia, Constantino

2016-01-01

Secondary cavity nesting (SCN) birds breed in holes that they do not excavate themselves. This is possible where there are large trees whose size and age permit the digging of holes by primary excavators and only rarely happens in forest plantations, where we expected a deficit of both breeding holes and SCN species. We assessed whether the availability of tree cavities influenced the number of SCNs in two temperate forest types, and evaluated the change in number of SCNs after adding nest boxes. First, we counted all cavities within each of our 25-m radius sampling points in mature and young forest plots during 2009. We then added nest boxes at standardised locations during 2010 and 2011 and conducted fortnightly bird counts (January-October 2009-2011). In 2011 we added two extra plots of each forest type, where we also conducted bird counts. Prior to adding nest boxes, counts revealed more SCNs in mature than in young forest. Following the addition of nest boxes, the number of SCNs increased significantly in the points with nest boxes in both types of forest. Counts in 2011 confirmed the increase in number of birds due to the addition of nest boxes. Given the likely benefits associated with a richer bird community we propose that, as is routinely done in some countries, forest management programs preserve old tree stumps and add nest boxes to forest plantations in order to increase bird numbers and bird community diversity.

Microbial air quality in mass transport buses and work-related illness among bus drivers of Bangkok Mass Transit Authority.

PubMed

Luksamijarulkul, Pipat; Sundhiyodhin, Viboonsri; Luksamijarulkul, Soavalug; Kaewboonchoo, Orawan

2004-06-01

The air quality in mass transport buses, especially air-conditioned buses may affect bus drivers who work full time. Bus numbers 16, 63, 67 and 166 of the Seventh Bus Zone of Bangkok Mass Transit Authority were randomly selected to investigate for microbial air quality. Nine air-conditioned buses and 2-4 open-air buses for each number of the bus (36 air-conditioned buses and 12 open-air buses) were included. Five points of in-bus air samples in each studied bus were collected by using the Millipore A ir Tester Totally, 180 and 60 air samples collected from air-conditioned buses and open-air buses were cultured for bacterial and fungal counts. The bus drivers who drove the studied buses were interviewed towards histories of work-related illness while working. The results revealed that the mean +/- SD of bacterial counts in the studied open-air buses ranged from 358.50 +/- 146.66 CFU/m3 to 506 +/- 137.62 CFU/m3; bus number 16 had the highest level. As well as the mean +/- SD of fungal counts which ranged from 93.33 +/- 44.83 CFU/m3 to 302 +/- 294.65 CFU/m3; bus number 166 had the highest level. Whereas, the mean +/- SD of bacterial counts in the studied air-conditioned buses ranged from 115.24 +/- 136.01 CFU/m3 to 244.69 +/- 234.85 CFU/m3; bus numbers 16 and 67 had the highest level. As well as the mean +/- SD of fungal counts which rangedfrom 18.84 +/- 39.42 CFU/m3 to 96.13 +/- 234.76 CFU/m3; bus number 166 had the highest level. When 180 and 60 studied air samples were analyzed in detail, it was found that 33.33% of the air samples from open-air buses and 6.11% of air samples from air-conditioned buses had a high level of bacterial counts (> 500 CFU/m3) while 6.67% of air samples from open-air buses and 2.78% of air samples from air-conditioned buses had a high level of fungal counts (> 500 CFU/m3). Data from the history of work-related illnesses among the studied bus drivers showed that 91.67% of open-air bus drivers and 57.28% of air-conditioned bus drivers had symptoms of work-related illnesses, p = 0.0185.

Application of Positron Doppler Broadening Spectroscopy to the Measurement of the Uniformity of Composite Materials

NASA Astrophysics Data System (ADS)

Quarles, C. A.; Sheffield, Thomas; Stacy, Scott; Yang, Chun

2009-03-01

The uniformity of rubber-carbon black composite materials has been investigated with positron Doppler Broadening Spectroscopy (DBS). The number of grams of carbon black (CB) mixed into one hundred grams of rubber, phr, is used to characterize a sample. A typical concentration for rubber in tires is 50 phr. The S parameter measured by DBS has been found to depend on the phr of the sample as well as the type of rubber and carbon black. The variation in carbon black concentration within a surface area of about 5 mm diameter can be measured by moving a standard Na-22 or Ge-68 positron source over an extended sample. The precision of the concentration measurement depends on the dwell time at a point on the sample. The time required to determine uniformity over an extended sample can be reduced by running with much higher counting rate than is typical in DBS and correcting for the systematic variation of S parameter with counting rate. Variation in CB concentration with mixing time at the level of about 0.5% has been observed.

Microbial Quality and Phylogenetic Diversity of Fresh Rainwater and Tropical Freshwater Reservoir

PubMed Central

Kaushik, Rajni; Balasubramanian, Rajasekhar; Dunstan, Hugh

2014-01-01

The impact of rainwater on the microbial quality of a tropical freshwater reservoir through atmospheric wet deposition of microorganisms was studied for the first time. Reservoir water samples were collected at four different sampling points and rainwater samples were collected in the immediate vicinity of the reservoir sites for a period of four months (January to April, 2012) during the Northeast monsoon period. Microbial quality of all fresh rainwater and reservoir water samples was assessed based on the counts for the microbial indicators: Escherichia coli (E. coli), total coliforms, and Enterococci along with total heterotrophic plate counts (HPC). The taxonomic richness and phylogenetic relationship of the freshwater reservoir with those of the fresh rainwater were also assessed using 16 S rRNA gene clone library construction. The levels of E. coli were found to be in the range of 0 CFU/100 mL – 75 CFU/100 mL for the rainwater, and were 10–94 CFU/100 mL for the reservoir water. The sampling sites that were influenced by highway traffic emissions showed the maximum counts for all the bacterial indicators assessed. There was no significant increase in the bacterial abundances observed in the reservoir water immediately following rainfall. However, the composite fresh rainwater and reservoir water samples exhibited broad phylogenetic diversity, including sequences representing Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, Lentisphaerae and Bacteriodetes. Members of the Betaproteobacteria group were the most dominant in both fresh rainwater and reservoir water, followed by Alphaproteobacteria, Sphingobacteria, Actinobacteria and Gammaproteobacteria. PMID:24979573

Microbial quality and phylogenetic diversity of fresh rainwater and tropical freshwater reservoir.

PubMed

Kaushik, Rajni; Balasubramanian, Rajasekhar; Dunstan, Hugh

2014-01-01

The impact of rainwater on the microbial quality of a tropical freshwater reservoir through atmospheric wet deposition of microorganisms was studied for the first time. Reservoir water samples were collected at four different sampling points and rainwater samples were collected in the immediate vicinity of the reservoir sites for a period of four months (January to April, 2012) during the Northeast monsoon period. Microbial quality of all fresh rainwater and reservoir water samples was assessed based on the counts for the microbial indicators: Escherichia coli (E. coli), total coliforms, and Enterococci along with total heterotrophic plate counts (HPC). The taxonomic richness and phylogenetic relationship of the freshwater reservoir with those of the fresh rainwater were also assessed using 16 S rRNA gene clone library construction. The levels of E. coli were found to be in the range of 0 CFU/100 mL-75 CFU/100 mL for the rainwater, and were 10-94 CFU/100 mL for the reservoir water. The sampling sites that were influenced by highway traffic emissions showed the maximum counts for all the bacterial indicators assessed. There was no significant increase in the bacterial abundances observed in the reservoir water immediately following rainfall. However, the composite fresh rainwater and reservoir water samples exhibited broad phylogenetic diversity, including sequences representing Betaproteobacteria, Alphaproteobacteria, Gammaproteobacteria, Actinobacteria, Lentisphaerae and Bacteriodetes. Members of the Betaproteobacteria group were the most dominant in both fresh rainwater and reservoir water, followed by Alphaproteobacteria, Sphingobacteria, Actinobacteria and Gammaproteobacteria.

Point Counts Modifications and Breeding Bird Abundances in Central Appalachian Forests

Treesearch

J. Edwards Gates

1995-01-01

The effects of point count duration and radius on detection of breeding birds were compared by recording all birds seen or heard within two consecutive 5-minute intervals and for fixed-radius (within 30 m) or unlimited radius counts. Counts were conducted on Green Ridge State Forest (GRSF) and Savage River State Forest (SRSF) in western Maryland. More than 70 percent...

Monitoring trends in bird populations: addressing background levels of annual variability in counts

Treesearch

Jared Verner; Kathryn L. Purcell; Jennifer G. Turner

1996-01-01

Point counting has been widely accepted as a method for monitoring trends in bird populations. Using a rigorously standardized protocol at 210 counting stations at the San Joaquin Experimental Range, Madera Co., California, we have been studying sources of variability in point counts of birds. Vegetation types in the study area have not changed during the 11 years of...

Effect of gaseous ozone on Enterococcus faecalis biofilm-an in vitro study.

PubMed

Boch, Tanja; Tennert, Christian; Vach, Kirstin; Al-Ahmad, Ali; Hellwig, Elmar; Polydorou, Olga

2016-09-01

The aim of this study was to evaluate the antimicrobial effect of gaseous ozone compared to conventional methods against Enterococcus faecalis. One hundred twenty-five teeth were infected by E. faecalis and were incubated for 72 h to form biofilm. Teeth were distributed among five groups. In the first group, ozone was used; in the second group, teeth were rinsed with 20 % ethylenediaminetetraacetic acid (EDTA); in the third group, with 3 % sodium hypochlorite (NaOCl). Group 4 combined 20 % EDTA with ozone. NaOCl and ozone were combined in group 5. After treatment, the samples with paper points were taken, followed by dentin samples taken with K-file, and cultured for 24 h. Then bacterial colonies were counted. All treatments reduced significantly (p < 0.05) the bacteria. Paper points' samples showed 85.38 % reduction after ozone. The highest reduction was observed in NaOCl group (99.98 %). EDTA reduced bacteria by 80.64 %. Combination of NaOCl and ozone eradicated 99.95 % of the bacteria. Combination of EDTA and ozone reduced E. faecalis up to 91.33 %. The dentin chips showed the following: the highest CFU counts were observed in EDTA group, followed by ozone and NaOCl group. The lowest CFU counts were found in NaOCl-ozone group and EDTA-ozone group. Ozone reduced E. faecalis, even organised in a biofilm, however, lower than NaOCl. No treatment reduced totally the bacteria. Used as an adjuvant, ozone can increase the efficacy of conventional rinsing like EDTA and presents an alternative treatment when NaOCl cannot be used e.g. in teeth with a wide-open apical foramen.

A method for optimum PSA setting in the absence of a pure α or β emitter and its application in the determination of (237)Np/(233)Pa.

PubMed

Feng, Xiao-gui; He, Qian-ge; Wang, Jian-chen; Chen, Jing

2014-11-01

In the application of liquid scintillation counting (LSC), the α/β discrimination is carried out with the function of pulse shape analysis (PSA), which requires the setting of the optimum PSA level. The optimum PSA are usually determined by the generation of cross-over plots, whereby a pair of vials, one containing a pure α emitter and the other a pure β emitter, is counted. However, in some cases such as the determination of (237)Np/(233)Pa, a pure α emitter or a pure β emitter is not available. Therefore, we have developed a new approach to set the optimum PSA by measuring the sample itself of mixed α/β emitters. The count rate of the sample in the α-multi-channel analyzer changes monotonically with the increase of the PSA, and there is always an inflection point which is related to the optimum PSA. By fitting the data near the inflection point with the function y=ax(3)+bx(2)+cx+d, we can obtain the optimum PSA as -b/(3a), which can be used to determine the radioactivity of (237)Np/(233)Pa. The results obtained with this new approach were in good agreement with those obtained by HPGe γ spectrometry that was calibrated with an LSC sample of (237)Np/(233)Pa under a radioactive secular equilibrium. The new approach is promising to be used in simultaneous determination of gross α and β emitters, especially in the absence of a pure α or β emitter. Copyright © 2014 Elsevier Ltd. All rights reserved.

Does pregnancy have an impact on the subgingival microbiota?

PubMed

Adriaens, Laurence M; Alessandri, Regina; Spörri, Stefan; Lang, Niklaus P; Persson, G Rutger

2009-01-01

We investigated clinical and subgingival microbiologic changes during pregnancy in 20 consecutive pregnant women > or =18 years not receiving dental care. Bacterial samples from weeks 12, 28, and 36 of pregnancy and at 4 to 6 weeks postpartum were processed for 37 species by checkerboard DNA-DNA hybridization. Clinical periodontal data were collected at week 12 and at 4 to 6 weeks postpartum, and bleeding on probing (BOP) was recorded at sites sampled at the four time points. The mean BOP at week 12 and postpartum was 40.1% +/- 18.2% and 27.4% +/- 12.5%, respectively. The corresponding mean BOP at microbiologic test sites was 15% (week 12) and 21% (postpartum; not statistically significant). Total bacterial counts decreased between week 12 and postpartum (P <0.01). Increased bacterial counts over time were found for Neisseria mucosa (P <0.001). Lower counts (P <0.001) were found for Capnocytophaga ochracea, Capnocytophaga sputigena, Eubacterium saburreum, Fusobacterium nucleatum naviforme, Fusobacterium nucleatum polymorphum, Leptotrichia buccalis, Parvimonas micra (previously Peptostreptococcus micros or Micromonas micros), Prevotella intermedia, Prevotella melaninogenica, Staphylococcus aureus, Streptococcus anginosus, Streptococcus intermedius, Streptococcus mutans, Streptococcus oralis, Streptococcus sanguinis, Selenomonas noxia, and Veillonella parvula. No changes occurred between weeks 12 and 28 of pregnancy. Counts of Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Tannerella forsythia (previously T. forsythensis), and Treponema denticola did not change. Counts of P. gingivalis and T. forsythia at week 12 were associated with gingivitis (P <0.001). Subgingival levels of bacteria associated with periodontitis did not change. P. gingivalis and T. forsythia counts were associated with BOP at week 12. A decrease was found in 17 of 37 species from week 12 to postpartum. Only counts of N. mucosa increased.

Integration of semiconductor quantum dots into nano-bio-chip systems for enumeration of CD4+ T cell counts at the point-of-need†‡

PubMed Central

Jokerst, Jesse V.; Floriano, Pierre N.; Christodoulides, Nicolaos; Simmons, Glennon W.; McDevitt, John T.

2010-01-01

Recent humanitarian efforts have led to the widespread release of antiretroviral drugs for the treatment of the more than 33 million HIV afflicted people living in resource-scarce settings. Here, the enumeration of CD4+ T lymphocytes is required to establish the level at which the immune system has been compromised. The gold standard method used in developed countries, based on flow cytometry, though widely accepted and accurate, is precluded from widespread use in resource-scarce settings due to its high expense, high technical requirements, difficulty in operation-maintenance and the lack of portability for these sophisticated laboratory-confined systems. As part of continuing efforts to develop practical diagnostic instrumentation, the integration of semiconductor nanocrystals (quantum dots, QDs) into a portable microfluidic-based lymphocyte capture and detection device is completed. This integrated system is capable of isolating and counting selected lymphocyte sub-populations (CD3+CD4+) from whole blood samples. By combining the unique optical properties of the QDs with the sample handling capabilities and cost effectiveness of novel microfluidic systems, a practical, portable lymphocyte measurement modality that correlates nicely with flow cytometry (R2 = 0.97) has been developed. This QD-based system reduces the optical requirements significantly relative to molecular fluorophores and the mini-CD4 counting device is projected to be suitable for use in both point-of-need and resource-scarce settings. PMID:19023471

Monitoring of Microbial Contaminants of Beef, Pork, and Chicken in HACCP Implemented Meat Processing Plants of Korea.

PubMed

Kim, Jung Hyun; Hur, Sun Jin; Yim, Dong Gyun

2018-04-01

This research was to evaluate microbial contamination levels in meat samples at hazard analysis critical control point (HACCP)-implemented processing plants that produce beef, pork, and chicken. During a period of about a year, a total of 178 samples (76 from beef, 89 from pork, and 13 from chicken) were obtained from raw materials (21.3%) and final products (78.7%). All samples were determined for each 25 g homogenized one. Samples were analyzed to determine the total aerobic plate count (APC), coliform count (CC), and E. coli count (ECC). By month, APC levels were the highest in September and the lowest in February ( p <0.001). In comparison among season, APC levels in meat samples were the highest in the summer and the lowest in winter ( p <0.001). By month, the highest CC prevalence was found in August, followed by October and then July ( p <0.001). By season, the highest CC was obtained in summer, followed by autumn and then spring ( p <0.001). All samples were negative for ECC. There was a direct correlation between the product form and coliform presence ( p <0.001). In addition, there was a positive correlation between the APC and CC (r=0.261). The APCs in analyzed samples ranged from below <10 1 CFU/g to <10 7 CFU/g. In conclusion, the month and season had significant effects on microbial contamination levels at HACCP implemented processing plants. Interrelationships between (i) the product form and coliform, (ii) the APC and CC were revealed.

The SWIFT AGN and Cluster Survey. I. Number Counts of AGNs and Galaxy Clusters

NASA Astrophysics Data System (ADS)

Dai, Xinyu; Griffin, Rhiannon D.; Kochanek, Christopher S.; Nugent, Jenna M.; Bregman, Joel N.

2015-05-01

The Swift active galactic nucleus (AGN) and Cluster Survey (SACS) uses 125 deg2 of Swift X-ray Telescope serendipitous fields with variable depths surrounding γ-ray bursts to provide a medium depth (4× {{10}-15} erg cm-2 s-1) and area survey filling the gap between deep, narrow Chandra/XMM-Newton surveys and wide, shallow ROSAT surveys. Here, we present a catalog of 22,563 point sources and 442 extended sources and examine the number counts of the AGN and galaxy cluster populations. SACS provides excellent constraints on the AGN number counts at the bright end with negligible uncertainties due to cosmic variance, and these constraints are consistent with previous measurements. We use Wide-field Infrared Survey Explorer mid-infrared (MIR) colors to classify the sources. For AGNs we can roughly separate the point sources into MIR-red and MIR-blue AGNs, finding roughly equal numbers of each type in the soft X-ray band (0.5-2 keV), but fewer MIR-blue sources in the hard X-ray band (2-8 keV). The cluster number counts, with 5% uncertainties from cosmic variance, are also consistent with previous surveys but span a much larger continuous flux range. Deep optical or IR follow-up observations of this cluster sample will significantly increase the number of higher-redshift (z\\gt 0.5) X-ray-selected clusters.

Water quality problems associated with intermittent water supply.

PubMed

Tokajian, S; Hashwa, F

2003-01-01

A controlled study was conducted in Lebanon over a period of 12 months to determine bacterial regrowth in a small network supplying the Beirut suburb of Naccache that had a population of about 3,000. The residential area, which is fed by gravity, is supplied twice a week with chlorinated water from two artesian wells of a confined aquifer. A significant correlation was detected between the turbidity and the levels of heterotrophic plate count bacteria (HPC) in the samples from the distribution network as well as from the artesian wells. However, a negative significant correlation was found between the temperature and the HPC count in the samples collected from the source. A statistically significant increase in counts, possibly due to regrowth, was repeatedly established between two sampling points lying on a straight distribution line but 1 km apart. Faecal coliforms were detected in the source water but none in the network except during a pipe breakage incident with confirmed Escherichia coli reaching 40 CFU/100 mL. However, coliforms such as Citrobacter freundii, Enterobacter agglomerans, E. cloacae and E. skazakii were repeatedly isolated from the network, mainly due to inadequate chlorination. A second controlled study was conducted to determine the effect of storage on the microbial quality of household storage tanks (500 L), which were of two main types - galvanized cast iron and black polyethylene. The mean bacterial count increased significantly after 7 d storage in both tank types. A significant difference was found in the mean HPC/mL between the winter and the summer. Highest counts were found April-June although the maximum temperature was reported later in the summer. A positive correlation was established between the HPC/mL and pH, temperature and storage time.

Tailoring point counts for inference about avian density: dealing with nondetection and availability

USGS Publications Warehouse

Johnson, Fred A.; Dorazio, Robert M.; Castellón, Traci D.; Martin, Julien; Garcia, Jay O.; Nichols, James D.

2014-01-01

Point counts are commonly used for bird surveys, but interpretation is ambiguous unless there is an accounting for the imperfect detection of individuals. We show how repeated point counts, supplemented by observation distances, can account for two aspects of the counting process: (1) detection of birds conditional on being available for observation and (2) the availability of birds for detection given presence. We propose a hierarchical model that permits the radius in which birds are available for detection to vary with forest stand age (or other relevant habitat features), so that the number of birds available at each location is described by a Poisson-gamma mixture. Conditional on availability, the number of birds detected at each location is modeled by a beta-binomial distribution. We fit this model to repeated point count data of Florida scrub-jays and found evidence that the area in which birds were available for detection decreased with increasing stand age. Estimated density was 0.083 (95%CI: 0.060–0.113) scrub-jays/ha. Point counts of birds have a number of appealing features. Based on our findings, however, an accounting for both components of the counting process may be necessary to ensure that abundance estimates are comparable across time and space. Our approach could easily be adapted to other species and habitats.

Model-based approaches to deal with detectability: a comment on Hutto (2016)

USGS Publications Warehouse

Marques, Tiago A.; Thomas, Len; Kéry, Marc; Buckland, Steve T.; Borchers, David L.; Rexstad, Eric; Fewster, Rachel M.; MacKenzie, Darryl I.; Royle, Andy; Guillera-Arroita, Gurutzeta; Handel, Colleen M.; Pavlacky, David C.; Camp, Richard J.

2017-01-01

In a recent paper, Hutto (2016a) challenges the need to account for detectability when interpreting data from point counts. A number of issues with model-based approaches to deal with detectability are presented, and an alternative suggested: surveying an area around each point over which detectability is assumed certain. The article contains a number of false claims and errors of logic, and we address these here. We provide suggestions about appropriate uses of distance sampling and occupancy modeling, arising from an intersection of design- and model-based inference.

Using the spatial and spectral precision of satellite imagery to predict wildlife occurrence patterns.

Treesearch

Edward J. Laurent; Haijin Shi; Demetrios Gatziolis; Joseph P. LeBouton; Michael B. Walters; Jianguo Liu

2005-01-01

We investigated the potential of using unclassified spectral data for predicting the distribution of three bird species over a -400,000 ha region of Michigan's Upper Peninsula using Landsat ETM+ imagery and 433 locations sampled for birds through point count surveys. These species, Black-throated Green Warbler, Nashville Warbler, and Ovenbird. were known to be...

Evaluation of petrifilm series 2000 as a possible rapid method to count coliforms in foods.

PubMed

Priego, R; Medina, L M; Jordano, R

2000-08-01

This research note is a preliminary comparison between the Petrifilm 2000 method and a widely used traditional enumeration method (on violet red bile agar); six batches of different foods (egg, frozen green beans, fresh sausage, a bakery product, raw minced meat, and raw milk) were studied. The reliability of the presumptive counts taken at 10, 12, and 14 h of incubation using this method was also verified by comparing the counts with the total confirmed counts at 24 h. In all the batches studied, results obtained with Petrifilm 2000 presented a close correlation to those obtained using violet red bile agar (r = 0.860) and greater sensitivity (93.33% of the samples displayed higher counts on Petrifilm 2000), showing that this method is a reliable and efficient alternative. The count taken at 10-h incubation is of clear interest as an early indicator of results in microbiological food control, since it accounted for 90% of the final count in all the batches analyzed. Counts taken at 12 and 14 h bore a greater similarity to those taken at 24 h. The Petrifilm 2000 method provides results in less than 12 h of incubation, making it a possible rapid method that adapts perfectly to hazard analysis critical control point system by enabling the microbiological quality control of the processing.

Accuracy of neutron self-activation method with iodine-containing scintillators for quantifying 128I generation using decay-fitting technique

NASA Astrophysics Data System (ADS)

Nohtomi, Akihiro; Wakabayashi, Genichiro

2015-11-01

We evaluated the accuracy of a self-activation method with iodine-containing scintillators in quantifying 128I generation in an activation detector; the self-activation method was recently proposed for photo-neutron on-line measurements around X-ray radiotherapy machines. Here, we consider the accuracy of determining the initial count rate R0, observed just after termination of neutron irradiation of the activation detector. The value R0 is directly related to the amount of activity generated by incident neutrons; the detection efficiency of radiation emitted from the activity should be taken into account for such an evaluation. Decay curves of 128I activity were numerically simulated by a computer program for various conditions including different initial count rates (R0) and background rates (RB), as well as counting statistical fluctuations. The data points sampled at minute intervals and integrated over the same period were fit by a non-linear least-squares fitting routine to obtain the value R0 as a fitting parameter with an associated uncertainty. The corresponding background rate RB was simultaneously calculated in the same fitting routine. Identical data sets were also evaluated by a well-known integration algorithm used for conventional activation methods and the results were compared with those of the proposed fitting method. When we fixed RB = 500 cpm, the relative uncertainty σR0 /R0 ≤ 0.02 was achieved for R0/RB ≥ 20 with 20 data points from 1 min to 20 min following the termination of neutron irradiation used in the fitting; σR0 /R0 ≤ 0.01 was achieved for R0/RB ≥ 50 with the same data points. Reasonable relative uncertainties to evaluate initial count rates were reached by the decay-fitting method using practically realistic sampling numbers. These results clarified the theoretical limits of the fitting method. The integration method was found to be potentially vulnerable to short-term variations in background levels, especially instantaneous contaminations by spike-like noise. The fitting method easily detects and removes such spike-like noise.

Comparison of line transects and point counts for monitoring spring migration in forested wetlands

USGS Publications Warehouse

Wilson, R.R.; Twedt, D.J.; Elliott, A.B.

2000-01-01

We compared the efficacy of 400-m line transects and sets of three point counts at detecting avian richness and abundance in bottomland hardwood forests and intensively managed cottonwood (Populus deltoides) plantations within the Mississippi Alluvial Valley. We detected more species and more individuals on line transects than on three point counts during 218 paired surveys conducted between 24 March and 3 June, 1996 and 1997. Line transects also yielded more birds per unit of time, even though point counts yielded higher estimates of relative bird density. In structurally more-complex bottomland hardwood forests, we detected more species and individuals on line transects, but in more-open cottonwood plantations, transects surpassed point counts only at detecting species within 50 m of the observer. Species richness and total abundance of Nearctic-Neotropical migrants and temperate migrants were greater on line transects within bottomland hardwood forests. Within cottonwood plantations, however, only species richness of Nearctic-Neotropical migrants and total abundance of temperate migrants were greater on line transects. Because we compared survey techniques using the same observer, within the same forest stand on a given day, we assumed that the technique yielding greater estimates of avian species richness and total abundance per unit of effort is superior. Thus, for monitoring migration within hardwood forests of the Mississippi Alluvial Valley, we recommend using line transects instead of point counts.

A relationship between salivary flow rates and Candida counts in patients with xerostomia.

PubMed

Nadig, Suchetha Devendrappa; Ashwathappa, Deepak Timmasandra; Manjunath, Muniraju; Krishna, Sowmya; Annaji, Araleri Gopalkrishna; Shivaprakash, Praveen Kunigal

2017-01-01

Most of the adult population is colonized by Candida in their oral cavity. The process of colonization depends on several factors, including the interaction between Candida and salivary proteins. Therefore, salivary gland hypofunction may alter the oral microbiota and increase the risk for opportunistic infections, such as candidiasis. Hence, it is necessary to evaluate the relationship between salivary flow rates (SFRs) and Candida colony counts in the saliva of patients with xerostomia. This study aims to determine and evaluate the relationship between SFRs and Candida colony forming units (CFUs) in patients with xerostomia. This study was a descriptive study. The study participants were taken from the patients attending outpatient department in a private dental college. Fifty patients, who reported xerostomia in a questionnaire of the symptoms of xerostomia, were selected. Chewing stimulated whole saliva samples were collected from them and their SFRs were assessed. Saliva samples were inoculated in the Sabouraud dextrose agar culture media for 24-48 h, and Candida CFUs were counted. Chi-squared test was used to analyze the data. There was a significant inverse relationship between salivary flow and candida CFUs count when patients with high colony counts were analyzed (cutoff point of 400 or greater CFU/mL). Females had less SFR than males. Most of the patients who had hyposalivation were taking medication for the underlying systemic diseases. Candida albicans was the most frequent species. There was a significantly negative correlation between SFRs and Candida CFUs in the patients with xerostomia.

Pre- and post-experimental manipulation assessments confirm the increase in number of birds due to the addition of nest boxes

PubMed Central

Cuatianquiz Lima, Cecilia

2016-01-01

Secondary cavity nesting (SCN) birds breed in holes that they do not excavate themselves. This is possible where there are large trees whose size and age permit the digging of holes by primary excavators and only rarely happens in forest plantations, where we expected a deficit of both breeding holes and SCN species. We assessed whether the availability of tree cavities influenced the number of SCNs in two temperate forest types, and evaluated the change in number of SCNs after adding nest boxes. First, we counted all cavities within each of our 25-m radius sampling points in mature and young forest plots during 2009. We then added nest boxes at standardised locations during 2010 and 2011 and conducted fortnightly bird counts (January–October 2009–2011). In 2011 we added two extra plots of each forest type, where we also conducted bird counts. Prior to adding nest boxes, counts revealed more SCNs in mature than in young forest. Following the addition of nest boxes, the number of SCNs increased significantly in the points with nest boxes in both types of forest. Counts in 2011 confirmed the increase in number of birds due to the addition of nest boxes. Given the likely benefits associated with a richer bird community we propose that, as is routinely done in some countries, forest management programs preserve old tree stumps and add nest boxes to forest plantations in order to increase bird numbers and bird community diversity. PMID:26998410

Inhomogeneity of the density of Parascaris spp. eggs in faeces of individual foals and the use of hypothesis testing for treatment decision making.

PubMed

Wilkes, E J A; Cowling, A; Woodgate, R G; Hughes, K J

2016-10-15

Faecal egg counts (FEC) are used widely for monitoring of parasite infection in animals, treatment decision-making and estimation of anthelmintic efficacy. When a single count or sample mean is used as a point estimate of the expectation of the egg distribution over some time interval, the variability in the egg density is not accounted for. Although variability, including quantifying sources, of egg count data has been described, the spatiotemporal distribution of nematode eggs in faeces is not well understood. We believe that statistical inference about the mean egg count for treatment decision-making has not been used previously. The aim of this study was to examine the density of Parascaris eggs in solution and faeces and to describe the use of hypothesis testing for decision-making. Faeces from two foals with Parascaris burdens were mixed with magnesium sulphate solution and 30 McMaster chambers were examined to determine the egg distribution in a well-mixed solution. To examine the distribution of eggs in faeces from an individual animal, three faecal piles from a foal with a known Parascaris burden were obtained, from which 81 counts were performed. A single faecal sample was also collected daily from 20 foals on three consecutive days and a FEC was performed on three separate portions of each sample. As appropriate, Poisson or negative binomial confidence intervals for the distribution mean were calculated. Parascaris eggs in a well-mixed solution conformed to a homogeneous Poisson process, while the egg density in faeces was not homogeneous, but aggregated. This study provides an extension from homogeneous to inhomogeneous Poisson processes, leading to an understanding of why Poisson and negative binomial distributions correspondingly provide a good fit for egg count data. The application of one-sided hypothesis tests for decision-making is presented. Copyright © 2016 Elsevier B.V. All rights reserved.

Effects of Point Count Duration, Time-of-Day, and Aural Stimuli on Detectability of Migratory and Resident Bird Species in Quintana Roo, Mexico

Treesearch

James F. Lynch

1995-01-01

Effects of count duration, time-of-day, and aural stimuli were studied in a series of unlimited-radius point counts conducted during winter in Quintana Roo, Mexico. The rate at which new species were detected was approximately three times higher during the first 5 minutes of each 15- minute count than in the final 5 minutes. The number of individuals and species...

Microbial contamination of meat during the skinning of beef carcass hindquarters at three slaughtering plants.

PubMed

Gill, C O; McGinnis, J C; Bryant, J

1998-07-21

The microbiological effects on the product of the series of operations for skinning the hindquarters of beef carcasses at three packing plants were assessed. Samples were obtained at each plant from randomly selected carcasses, by swabbing specified sites related to opening cuts, rump skinning or flank skinning operations, randomly selected sites along the lines of the opening cuts, or randomly selected sites on the skinned hindquarters of carcasses. A set of 25 samples of each type was collected at each plant, with the collection of a single sample from each selected carcass. Aerobic counts, coliforms and Escherichia coli were enumerated in each sample, and a log mean value was estimated for each set of 25 counts on the assumption of a log normal distribution of the counts. The data indicated that the hindquarters skinning operations at plant A were hygienically inferior to those at the other two plants, with mean numbers of coliforms and E. coli being about two orders of magnitude greater, and aerobic counts being an order of magnitude greater on the skinned hindquarters of carcasses from plant A than on those from plants B or C. The data further indicated that the operation for cutting open the skin at plant C was hygienically superior to the equivalent operation at plant B, but that the operations for skinning the rump and flank at plant B were hygienically superior to the equivalent operations at plant C. The findings suggest that objective assessment of the microbiological effects on carcasses of beef carcass dressing processes will be required to ensure that Hazard Analysis: Critical Control Point and Quality Management Systems are operated to control the microbiological condition of carcasses.

Imaging systems and algorithms to analyze biological samples in real-time using mobile phone microscopy.

PubMed

Shanmugam, Akshaya; Usmani, Mohammad; Mayberry, Addison; Perkins, David L; Holcomb, Daniel E

2018-01-01

Miniaturized imaging devices have pushed the boundaries of point-of-care imaging, but existing mobile-phone-based imaging systems do not exploit the full potential of smart phones. This work demonstrates the use of simple imaging configurations to deliver superior image quality and the ability to handle a wide range of biological samples. Results presented in this work are from analysis of fluorescent beads under fluorescence imaging, as well as helminth eggs and freshwater mussel larvae under white light imaging. To demonstrate versatility of the systems, real time analysis and post-processing results of the sample count and sample size are presented in both still images and videos of flowing samples.

Fecal contamination of drinking water within peri-urban households, Lima, Peru.

PubMed

Oswald, William E; Lescano, Andrés G; Bern, Caryn; Calderon, Maritza M; Cabrera, Lilia; Gilman, Robert H

2007-10-01

We assessed fecal contamination of drinking water in households in 2 peri-urban communities of Lima, Peru. We measured Escherichia coli counts in municipal source water and, within households, water from principal storage containers, stored boiled drinking water, and water in a serving cup. Source water was microbiologically clean, but 26 (28%) of 93 samples of water stored for cooking had fecal contamination. Twenty-seven (30%) of 91 stored boiled drinking water samples grew E. coli. Boiled water was more frequently contaminated when served in a drinking cup than when stored (P < 0.01). Post-source contamination increased successively through the steps of usage from source water to the point of consumption. Boiling failed to ensure safe drinking water at the point of consumption because of easily contaminated containers and poor domestic hygiene. Hygiene education, better point-of-use treatment and storage options, and in-house water connections are urgently needed.

Incomplete Recovery of CD4 count, CD4 Percentage, and CD4/CD8 ratio in HIV-Infected Patients on Long-Term Antiretroviral Therapy with Suppressed Viremia.

PubMed

Mutoh, Yoshikazu; Nishijima, Takeshi; Inaba, Yosuke; Tanaka, Noriko; Kikuchi, Yoshimi; Gatanaga, Hiroyuki; Oka, Shinichi

2018-03-02

The extent and duration of long-term recovery of CD4 count, CD4%, and CD4/CD8 ratio after initiation of combination antiretroviral therapy (cART) in patients with suppressed viral load are largely unknown. HIV-1 infected patients who started cART between January 2004 and January 2012 and showed persistent viral suppression (<200 copies/mL) for at least 4 years were followed up at AIDS Clinical Center, Tokyo. Change point analysis was used to determine the time point where CD4 count recovery shows a plateau, and linear mixed model was applied to estimate CD4 count at the change point. Data of 752 patients were analyzed [93% males, median age 38, median baseline CD4 count 172/µL (IQR, 62-253), CD4% 13.8% (IQR, 7.7-18.5), and CD4/8 ratio 0.23 (IQR, 0.12-0.35)]. The median follow-up period was 81.2 months and 91 (12.1%) patients were followed for >10 years. Change point analysis showed that CD4 count, CD4%, and CD4/CD8 ratio, continued to increase until 78.6, 62.2, and 64.3 months, respectively, with adjusted mean of 590 /µL (95%CI 572-608), 29.5% (29-30.1), and 0.89 (0.86-0.93), respectively, at the change point. Although 73.8% of the study patients achieved CD4 count ≥500 /μL, 48.2% of the patients with baseline CD4 count <100 /μL did not achieve CD4 count ≥500 /μL. Neither CD4% nor CD4/CD8 ratio normalized in a majority of patients. The results showed lack of normalization of CD4 count, CD4%, and CD4/CD8 ratio to the levels seen in healthy individuals even after long-term successful cART in patients with suppressed viral load.

Tender point count, pain, and mobility in the older population: the mobilize Boston study.

PubMed

Eggermont, Laura H P; Shmerling, Robert H; Leveille, Suzanne G

2010-01-01

Prevalence of tender points (TP), and widespread pain and fibromyalgia, as well as the relationship between TP and widespread pain and mobility, was examined in 585 community-dwelling older adults (mean age 78.2 years, 63.4% female). Pain was based on location (none, single site, multisite, widespread). Mobility was measured by the Short Physical Performance Battery (SPPB), gait speed, and self-reported (S-R) mobility difficulty. Tender-point count and health characteristics (ie, BMI, chronic conditions, analgesic use, number of medications, depression, and blocks walked per week) were assessed. Several participants had 3 or more TP (22.1%) although prevalence of criteria-based fibromyalgia was low (.3%). Mobility was more limited in persons with higher tender-point counts. After adjustment for pain and other risk factors, higher tender-point count was associated with poorer SPPB performance (score < 10, aOR = 1.09 per TP, 95%CI, 1.01-1.17), and slow gait speed (< .784m/sec, aOR = 1.14 per TP, 95%CI, 1.05-1.24), but not with S-R mobility difficulty. S-R mobility difficulty was associated with more disseminated pain (multisite pain, aOR = 2.01, 95%CI, 1.21-3.34; widespread pain, aOR = 2.47, 95%CI, 1.09-5.62). These findings portray a significant mobility burden related to tender-point count and multisite and widespread pain in the older population. Future studies using longitudinal methods are warranted. Higher tender-point count, multisite pain, and widespread pain are common in community-dwelling older adults and associated with mobility problems. Both the manual tender-point exam and the McGill Pain Map may provide important yet different information about risks for mobility disability in older individuals. Copyright 2010 American Pain Society. All rights reserved.

A hierarchical model combining distance sampling and time removal to estimate detection probability during avian point counts

USGS Publications Warehouse

Amundson, Courtney L.; Royle, J. Andrew; Handel, Colleen M.

2014-01-01

Imperfect detection during animal surveys biases estimates of abundance and can lead to improper conclusions regarding distribution and population trends. Farnsworth et al. (2005) developed a combined distance-sampling and time-removal model for point-transect surveys that addresses both availability (the probability that an animal is available for detection; e.g., that a bird sings) and perceptibility (the probability that an observer detects an animal, given that it is available for detection). We developed a hierarchical extension of the combined model that provides an integrated analysis framework for a collection of survey points at which both distance from the observer and time of initial detection are recorded. Implemented in a Bayesian framework, this extension facilitates evaluating covariates on abundance and detection probability, incorporating excess zero counts (i.e. zero-inflation), accounting for spatial autocorrelation, and estimating population density. Species-specific characteristics, such as behavioral displays and territorial dispersion, may lead to different patterns of availability and perceptibility, which may, in turn, influence the performance of such hierarchical models. Therefore, we first test our proposed model using simulated data under different scenarios of availability and perceptibility. We then illustrate its performance with empirical point-transect data for a songbird that consistently produces loud, frequent, primarily auditory signals, the Golden-crowned Sparrow (Zonotrichia atricapilla); and for 2 ptarmigan species (Lagopus spp.) that produce more intermittent, subtle, and primarily visual cues. Data were collected by multiple observers along point transects across a broad landscape in southwest Alaska, so we evaluated point-level covariates on perceptibility (observer and habitat), availability (date within season and time of day), and abundance (habitat, elevation, and slope), and included a nested point-within-transect and park-level effect. Our results suggest that this model can provide insight into the detection process during avian surveys and reduce bias in estimates of relative abundance but is best applied to surveys of species with greater availability (e.g., breeding songbirds).

Methods of detecting and counting raptors: A review

USGS Publications Warehouse

Fuller, M.R.; Mosher, J.A.; Ralph, C. John; Scott, J. Michael

1981-01-01

Most raptors are wide-ranging, secretive, and occur at relatively low densities. These factors, in conjunction with the nocturnal activity of owls, cause the counting of raptors by most standard census and survey efforts to be very time consuming and expensive. This paper reviews the most common methods of detecting and counting raptors. It is hoped that it will be of use to the ever-increasing number of biologists, land-use planners, and managers that must determine the occurrence, density, or population dynamics of raptors. Road counts of fixed station or continuous transect design are often used to sample large areas. Detection of spontaneous or elicited vocalizations, especially those of owls, provides a means of detecting and estimating raptor numbers. Searches for nests are accomplished from foot surveys, observations from automobiles and boats, or from aircraft when nest structures are conspicuous (e.g., Osprey). Knowledge of nest habitat, historic records, and inquiries of local residents are useful for locating nests. Often several of these techniques are combined to help find nest sites. Aerial searches have also been used to locate or count large raptors (e.g., eagles), or those that may be conspicuous in open habitats (e.g., tundra). Counts of birds entering or leaving nest colonies or colonial roosts have been attempted on a limited basis. Results from Christmas Bird Counts have provided an index of the abundance of some species. Trapping and banding generally has proven to be an inefficient method of detecting raptors or estimating their populations. Concentrations of migrants at strategically located points around the world afford the best opportunity to count many rap tors in a relatively short period of time, but the influence of many unquantified variables has inhibited extensive interpretation of these counts. Few data exist to demonstrate the effectiveness of these methods. We believe more research on sampling techniques, rather than complete counts or intensive searches, will provide adequate yet affordable estimates of raptor numbers in addition to providing methods for detecting the presence of raptors on areas of interest to researchers and managers.

Long-term post-wildfire correlates with avian community dynamics in ponderosa pine forests [Chapter J

Treesearch

Jamie S. Sanderlin; William M. Block; Brenda E. Strohmeyer

2016-01-01

We used a 10-year data set to illustrate the long-term correlates of wildfire on avian species richness in the ponderosa pine (Pinus ponderosa) forests of northern Arizona. This study was conducted in the vicinity of the Horseshoe and Hochderffer Fires, which occurred in 1996, and sampling began 1 year after the fires. Using point-count data from breeding...

Diversidad de aves en agropaisajes en la region norte de Nicaragua

Treesearch

Wayne J. Arendt; Marvin Tórrez; Sergio Vílchez

2012-01-01

Avian diversity in agroscapes in Nicaragua’s north highlands. – Nicaragua’s highland forests are threatened by continual wood extraction and encroaching agriculture. Still, the effects of forest loss and fragmentation on avian communities remain little known. We used fixed-width point counts (distance sampling: 4843 detections during 86 h of observation) to...

Bayesian analyses of time-interval data for environmental radiation monitoring.

PubMed

Luo, Peng; Sharp, Julia L; DeVol, Timothy A

2013-01-01

Time-interval (time difference between two consecutive pulses) analysis based on the principles of Bayesian inference was investigated for online radiation monitoring. Using experimental and simulated data, Bayesian analysis of time-interval data [Bayesian (ti)] was compared with Bayesian and a conventional frequentist analysis of counts in a fixed count time [Bayesian (cnt) and single interval test (SIT), respectively]. The performances of the three methods were compared in terms of average run length (ARL) and detection probability for several simulated detection scenarios. Experimental data were acquired with a DGF-4C system in list mode. Simulated data were obtained using Monte Carlo techniques to obtain a random sampling of the Poisson distribution. All statistical algorithms were developed using the R Project for statistical computing. Bayesian analysis of time-interval information provided a similar detection probability as Bayesian analysis of count information, but the authors were able to make a decision with fewer pulses at relatively higher radiation levels. In addition, for the cases with very short presence of the source (< count time), time-interval information is more sensitive to detect a change than count information since the source data is averaged by the background data over the entire count time. The relationships of the source time, change points, and modifications to the Bayesian approach for increasing detection probability are presented.

Avalanche photodiode photon counting receivers for space-borne lidars

NASA Technical Reports Server (NTRS)

Sun, Xiaoli; Davidson, Frederic M.

1991-01-01

Avalanche photodiodes (APD) are studied for uses as photon counting detectors in spaceborne lidars. Non-breakdown APD photon counters, in which the APD's are biased below the breakdown point, are shown to outperform: (1) conventional APD photon counters biased above the breakdown point; (2) conventional APD photon counters biased above the breakdown point; and (3) APD's in analog mode when the received optical signal is extremely weak. Non-breakdown APD photon counters were shown experimentally to achieve an effective photon counting quantum efficiency of 5.0 percent at lambda = 820 nm with a dead time of 15 ns and a dark count rate of 7000/s which agreed with the theoretically predicted values. The interarrival times of the counts followed an exponential distribution and the counting statistics appeared to follow a Poisson distribution with no after pulsing. It is predicted that the effective photon counting quantum efficiency can be improved to 18.7 percent at lambda = 820 nm and 1.46 percent at lambda = 1060 nm with a dead time of a few nanoseconds by using more advanced commercially available electronic components.

Improved confidence intervals when the sample is counted an integer times longer than the blank.

PubMed

Potter, William Edward; Strzelczyk, Jadwiga Jodi

2011-05-01

Past computer solutions for confidence intervals in paired counting are extended to the case where the ratio of the sample count time to the blank count time is taken to be an integer, IRR. Previously, confidence intervals have been named Neyman-Pearson confidence intervals; more correctly they should have been named Neyman confidence intervals or simply confidence intervals. The technique utilized mimics a technique used by Pearson and Hartley to tabulate confidence intervals for the expected value of the discrete Poisson and Binomial distributions. The blank count and the contribution of the sample to the gross count are assumed to be Poisson distributed. The expected value of the blank count, in the sample count time, is assumed known. The net count, OC, is taken to be the gross count minus the product of IRR with the blank count. The probability density function (PDF) for the net count can be determined in a straightforward manner.

Fixed-Radius Point Counts in Forests: Factors Influencing Effectiveness and Efficiency

Treesearch

Daniel R. Petit; Lisa J. Petit; Victoria A. Saab; Thomas E. Martin

1995-01-01

The effectiveness of fixed-radius point counts in quantifying abundance and richness of bird species in oak-hickory, pine-hardwoods, mixed-mesophytic, beech-maple, and riparian cottonwood forests was evaluated in Arkansas, Ohio, Kentucky, and Idaho. Effects of count duration and numbers of stations and visits per stand were evaluated in May to July 1991 by conducting...

Point counts from clustered populations: Lessons from an experiment with Hawaiian crows

USGS Publications Warehouse

Hayward, G.D.; Kepler, C.B.; Scott, J.M.

1991-01-01

We designed an experiment to identify factors contributing most to error in counts of Hawaiian Crow or Alala (Corvus hawaiiensis) groups that are detected aurally. Seven observers failed to detect calling Alala on 197 of 361 3-min point counts on four transects extending from cages with captive Alala. A detection curve describing the relation between frequency of flock detection and distance typified the distribution expected in transect or point counts. Failure to detect calling Alala was affected most by distance, observer, and Alala calling frequency. The number of individual Alala calling was not important in detection rate. Estimates of the number of Alala calling (flock size) were biased and imprecise: average difference between number of Alala calling and number heard was 3.24 (.+-. 0.277). Distance, observer, number of Alala calling, and Alala calling frequency all contributed to errors in estimates of group size (P < 0.0001). Multiple regression suggested that number of Alala calling contributed most to errors. These results suggest that well-designed point counts may be used to estimate the number of Alala flocks but cast doubt on attempts to estimate flock size when individuals are counted aurally.

Microbial changes in patients with acute periodontal abscess after treatment detected by PadoTest.

PubMed

Eguchi, T; Koshy, G; Umeda, M; Iwanami, T; Suga, J; Nomura, Y; Kawanami, M; Ishikawa, I

2008-03-01

To investigate changes in bacterial counts in subgingival plaque from patients with acute periodontal abscess by IAI-PadoTest. Ninety-one patients were randomly allocated to either test or control groups. In all the patients, pockets with acute periodontal abscess were irrigated with sterilized physiological saline, and in the test group, 2% minocycline hydrochloride ointment was applied once into the pocket in addition. Subgingival plaque samples were collected by paper point before treatment and 7 days after treatment. The total bacterial count was determined and Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis, Treponema denticola, and Tannerella forsythia, were detected using IAI-PadoTest, a DNA/RNA probe method. The total bacterial count decreased in both groups, with a significant decrease in the test group. The counts and number of sites positive for P. gingivalis, T. forsythia and T. denticola significantly decreased in the test group after treatment, compared with those in the control group. Pocket depth decreased in the both groups, with a statistically significant decrease in the test group. Topical treatment with minocycline in pockets with acute periodontal abscess was effective in reducing the bacterial counts as shown by the microbiological investigation using PadoTest 4.5.

Advantages and challenges in automated apatite fission track counting

NASA Astrophysics Data System (ADS)

Enkelmann, E.; Ehlers, T. A.

2012-04-01

Fission track thermochronometer data are often a core element of modern tectonic and denudation studies. Soon after the development of the fission track methods interest emerged for the developed an automated counting procedure to replace the time consuming labor of counting fission tracks under the microscope. Automated track counting became feasible in recent years with increasing improvements in computer software and hardware. One such example used in this study is the commercial automated fission track counting procedure from Autoscan Systems Pty that has been highlighted through several venues. We conducted experiments that are designed to reliably and consistently test the ability of this fully automated counting system to recognize fission tracks in apatite and a muscovite external detector. Fission tracks were analyzed in samples with a step-wise increase in sample complexity. The first set of experiments used a large (mm-size) slice of Durango apatite cut parallel to the prism plane. Second, samples with 80-200 μm large apatite grains of Fish Canyon Tuff were analyzed. This second sample set is characterized by complexities often found in apatites in different rock types. In addition to the automated counting procedure, the same samples were also analyzed using conventional counting procedures. We found for all samples that the fully automated fission track counting procedure using the Autoscan System yields a larger scatter in the fission track densities measured compared to conventional (manual) track counting. This scatter typically resulted from the false identification of tracks due surface and mineralogical defects, regardless of the image filtering procedure used. Large differences between track densities analyzed with the automated counting persisted between different grains analyzed in one sample as well as between different samples. As a result of these differences a manual correction of the fully automated fission track counts is necessary for each individual surface area and grain counted. This manual correction procedure significantly increases (up to four times) the time required to analyze a sample with the automated counting procedure compared to the conventional approach.

Revision of Viable Environmental Monitoring in a Development Pilot Plant Based on Quality Risk Assessment: A Case Study.

PubMed

Ziegler, Ildikó; Borbély-Jakab, Judit; Sugó, Lilla; Kovács, Réka J

2017-01-01

In this case study, the principles of quality risk management were applied to review sampling points and monitoring frequencies in the hormonal tableting unit of a formulation development pilot plant. In the cleanroom area, premises of different functions are located. Therefore a general method was established for risk evaluation based on the Hazard Analysis and Critical Control Points (HACCP) method to evaluate these premises (i.e., production area itself and ancillary clean areas) from the point of view of microbial load and state in order to observe whether the existing monitoring program met the emerged advanced monitoring practice. LAY ABSTRACT: In pharmaceutical production, cleanrooms are needed for the manufacturing of final dosage forms of drugs-intended for human or veterinary use-in order to protect the patient's weakened body from further infections. Cleanrooms are premises with a controlled level of contamination that is specified by the number of particles per cubic meter at a specified particle size or number of microorganisms (i.e. microbial count) per surface area. To ensure a low microbial count over time, microorganisms are detected and counted by environmental monitoring methods regularly. It is reasonable to find the easily infected places by risk analysis to make sure the obtained results really represent the state of the whole room. This paper presents a risk analysis method for the optimization of environmental monitoring and verification of the suitability of the method. © PDA, Inc. 2017.

Species richness, relative abundance, and habitat associations of nocturnal birds along the rio grande in Southern texas

USGS Publications Warehouse

Skoruppa, M.K.; Woodin, M.C.; Blacklock, G.

2009-01-01

The segment of the Rio Grande between International Falcon Reservoir and Del Rio, Texas (distance ca. 350 km), remains largely unexplored ornithologically. We surveyed nocturnal birds monthly during February-June 1998 at 19 stations along the Rio Grande (n = 6) and at upland stock ponds (n = 13) in Webb County, Texas. We conducted 10-min point counts (n = 89) after sunset and before moonset. Four species of owls and five species of nightjars were detected. Nightjars, as a group, were nearly five limes more abundant (mean number/count = 2.63) than owls (mean number = 0.55). The most, common owl, the great horned owl (Bubo virginianus), had a mean number of 0.25/point count. The mean for elf owls (Micrathene whitneyi) was 0.16/point count. The most common nightjars were the common poorwill (Phalaenoptilus nuttallii; 1.21/point count) and lesser nighthawk (Chordeiles acutipennir, 1.16/point count). Survey sites on the river supported more species (mean = 2.2) than did upland stock ponds (mean = 1.4). However, only one species (common pauraque, Nyctidromus albicollis) showed a preference for the river sites. Our results establish this segment of the Rio Grande in southern Texas as an area of high diversity of nightjars in the United States, matched (in numbers of species) only by southeastern Arizona and southwestern New Mexico.

Time dependent reduction in platelet aggregation using the multiplate analyser and hirudin blood due to platelet clumping.

PubMed

Chapman, Kent; Favaloro, Emmanuel J

2018-05-01

The Multiplate is a popular instrument that measures platelet function using whole blood. Potentially considered a point of care instrument, it is also used by hemostasis laboratories. The instrument is usually utilized to assess antiplatelet medication or as a screen of platelet function. According to the manufacturer, testing should be performed within 0.5-3 hours of blood collection, and preferably using manufacturer provided hirudin tubes. We report time-associated reduction in platelet aggregation using the Multiplate and hirudin blood collection tubes, for all the major employed agonists. Blood for Multiplate analysis was collected into manufacturer supplied hirudin tubes, and 21 consecutive samples assessed using manufacturer supplied agonists (ADP, arachidonic acid, TRAP, collagen and ristocetin), at several time-points post-sample collection within the recommended test time period. Blood was also collected into EDTA as a reference method for platelet counts, with samples collected into sodium citrate and hirudin used for comparative counts. All platelet agonists showed a diminution of response with time. Depending on the agonist, the reduction caused 5-20% and 22-47% of responses initially in the normal reference range to fall below the reference range at 120min and 180min, respectively. Considering any agonist, 35% and 67% of initially "normal" responses became 'abnormal' at 120 min and 180 min, respectively. Platelet counts showed generally minimal changes in EDTA blood, but were markedly reduced over time in both citrate and hirudin blood, with up to 40% and 60% reduction, respectively, at 240 min. The presence of platelet clumping (micro-aggregate formation) was also observed in a time dependent manner, especially for hirudin. In conclusion, considering any platelet agonist, around two-thirds of samples can, within the recommended 0.5-3 hour testing window post-blood collection, yield a reduction in platelet aggregation that may lead to a change in interpretation (i.e., normal to reduced). Thus, the stability of Multiplate testing can more realistically be considered as being between 30-120 min of blood collection for samples collected into hirudin.

Evaluation of Bias in Roadside Point Count Surveys of Passerines in Shrubsteppe and Grassland Habitats in Southwestern Idaho

Treesearch

John T. Rotenberry; Steven T. Knick

1995-01-01

Breeding passerine abundances in Great Basin shrubsteppe and grassland habitats were surveyed in southwestern Idaho by using 73 pairs of 200-m radius circular point counts. Points were placed along roads and paired with points 400 m away from roads but in similar habitat. Grassland species such as Horned Larks (Eremophila alpestris) and Western...

Interplanetary Scintillation studies with the Murchison Wide-field Array III: Comparison of source counts and densities for radio sources and their sub-arcsecond components at 162 MHz

NASA Astrophysics Data System (ADS)

Chhetri, R.; Ekers, R. D.; Morgan, J.; Macquart, J.-P.; Franzen, T. M. O.

2018-06-01

We use Murchison Widefield Array observations of interplanetary scintillation (IPS) to determine the source counts of point (<0.3 arcsecond extent) sources and of all sources with some subarcsecond structure, at 162 MHz. We have developed the methodology to derive these counts directly from the IPS observables, while taking into account changes in sensitivity across the survey area. The counts of sources with compact structure follow the behaviour of the dominant source population above ˜3 Jy but below this they show Euclidean behaviour. We compare our counts to those predicted by simulations and find a good agreement for our counts of sources with compact structure, but significant disagreement for point source counts. Using low radio frequency SEDs from the GLEAM survey, we classify point sources as Compact Steep-Spectrum (CSS), flat spectrum, or peaked. If we consider the CSS sources to be the more evolved counterparts of the peaked sources, the two categories combined comprise approximately 80% of the point source population. We calculate densities of potential calibrators brighter than 0.4 Jy at low frequencies and find 0.2 sources per square degrees for point sources, rising to 0.7 sources per square degree if sources with more complex arcsecond structure are included. We extrapolate to estimate 4.6 sources per square degrees at 0.04 Jy. We find that a peaked spectrum is an excellent predictor for compactness at low frequencies, increasing the number of good calibrators by a factor of three compared to the usual flat spectrum criterion.

Hygiene intervention reduces contamination of weaning food in Bangladesh.

PubMed

Islam, Mohammad Sirajul; Mahmud, Zahid Hayat; Gope, Partha Sarathi; Zaman, Rokon Uz; Hossain, Zakir; Islam, Mohammad Shafiqul; Mondal, Dinesh; Sharker, Mohammad Abu Yushuf; Islam, Khairul; Jahan, Hasin; Bhuiya, Abbas; Endtz, Hubert P; Cravioto, Alejandro; Curtis, Valerie; Touré, Ousmane; Cairncross, Sandy

2013-03-01

This study was conducted to measure the impact of a hygiene intervention on the contamination of weaning food in Bangladesh. Sixty households were selected: 30 study and 30 control households. Samples of weaning food were collected from all the 60 households at baseline and examined for faecal coliforms (FC), faecal streptococci (FS) and Clostridium perfringens (CP) following standard procedures. After cooking, food samples were collected on three occasions before feeding. Following Hazard Analysis Critical Control Point (HACCP) procedures, critical control points were determined. The mothers in the 30 study households were then trained for 4 weeks in how to attain the control point conditions. Then, again the food samples were collected and analysed. At baseline, weaning foods from study and control households were heavily contaminated with FC and FS. The FC and FS counts were 1.84 log(10) and 1.92 log(10) colony-forming unit (cfu)/g, respectively, in the study households, and 0.86 log(10) and 1.33 log(10)  cfu/g, respectively, in the control households in the first feeding. After the intervention, the FC and FS counts in study households had dropped to 0.10 log(10) and 0.09 log(10)  cfu/g, respectively, a statistically significant reduction (P < 0.001). Monitoring the sustainability of the behaviour change after 3 months showed that the mothers were maintaining food hygiene. A hygiene intervention following the HACCP approach reduced the weaning food contamination significantly. Awareness building among mothers about weaning food hygiene could be an important intervention for preventing weaning food-related diarrhoea in Bangladesh. © 2012 Blackwell Publishing Ltd.

A relationship between salivary flow rates and Candida counts in patients with xerostomia

PubMed Central

Nadig, Suchetha Devendrappa; Ashwathappa, Deepak Timmasandra; Manjunath, Muniraju; Krishna, Sowmya; Annaji, Araleri Gopalkrishna; Shivaprakash, Praveen Kunigal

2017-01-01

Context: Most of the adult population is colonized by Candida in their oral cavity. The process of colonization depends on several factors, including the interaction between Candida and salivary proteins. Therefore, salivary gland hypofunction may alter the oral microbiota and increase the risk for opportunistic infections, such as candidiasis. Hence, it is necessary to evaluate the relationship between salivary flow rates (SFRs) and Candida colony counts in the saliva of patients with xerostomia. Aims: This study aims to determine and evaluate the relationship between SFRs and Candida colony forming units (CFUs) in patients with xerostomia. Settings and Design: This study was a descriptive study. Subjects and Methods: The study participants were taken from the patients attending outpatient department in a private dental college. Fifty patients, who reported xerostomia in a questionnaire of the symptoms of xerostomia, were selected. Chewing stimulated whole saliva samples were collected from them and their SFRs were assessed. Saliva samples were inoculated in the Sabouraud dextrose agar culture media for 24–48 h, and Candida CFUs were counted. Statistical Analysis Used: Chi-squared test was used to analyze the data. Results: There was a significant inverse relationship between salivary flow and candida CFUs count when patients with high colony counts were analyzed (cutoff point of 400 or greater CFU/mL). Females had less SFR than males. Most of the patients who had hyposalivation were taking medication for the underlying systemic diseases. Candida albicans was the most frequent species. Conclusions: There was a significantly negative correlation between SFRs and Candida CFUs in the patients with xerostomia. PMID:28932047

Effects of bacterial pollution caused by a strong typhoon event and the restoration of a recreational beach: Transitions of fecal bacterial counts and bacterial flora in beach sand.

PubMed

Suzuki, Yoshihiro; Teranishi, Kotaro; Matsuwaki, Tomonori; Nukazawa, Kei; Ogura, Yoshitoshi

2018-05-28

To determine the effects of bacteria pollution associated with a strong typhoon event and to assess the restoration of the normal bacterial flora, we used conventional filtration methods and nextgeneration sequencing of 16S rRNA genes to analyze the transition of fecal and total bacterial counts in water and core sand samples collected from a recreational beach. Immediately after the typhoon event, Escherichia coli counts increased to 82 CFU/100 g in the surface beach sand. E. coli was detected through the surface to sand 85-cm deep at the land side point (10-m land side from the high-water line). However, E. coli disappeared within a month from the land side point. The composition of the bacterial flora in the beach sand at the land point was directly influenced by the typhoon event. Pseudomonas was the most prevalent genus throughout the sand layers (0-102-cm deep) during the typhoon event. After 3 months, the population of Pseudomonas significantly decreased, and the predominant genus in the surface layer was Kaistobacter, although Pseudomonas was the major genus in the 17- to 85-cm layer. When the beach conditions stabilized, the number of pollutant Pseudomonas among the 10 most abundant genera decreased to lower than the limit of detection. The bacterial population of the sand was subsequently restored to the most populous pre-event orders at the land point. A land-side beach, where users directly contact the sand, was significantly affected by bacterial pollution caused by a strong typhoon event. We show here that the normal bacterial flora of the surface sand was restored within 1 month. Copyright © 2018 Elsevier B.V. All rights reserved.

Effect of point-of-use, activated carbon filters on the bacteriological quality of rural groundwater supplies.

PubMed Central

Synder, J W; Mains, C N; Anderson, R E; Bissonnette, G K

1995-01-01

The water quality of 24 rural, domestic groundwater supplies treated with point-of-use, powdered activated carbon (PAC) filters was monitored to determine how such treatment might impact the bacteriological quality of private, residential drinking water supplies. Heterotrophic-plate-count (HPC) and total coliform analyses were performed on raw, PAC-treated, and overnight or stagnant (first-draw) PAC-treated water samples. Densities of HPC bacteria were elevated by 0.86 and 0.20 orders of magnitude for spring and well water systems, respectively, in PAC-treated effluents following overnight stagnation compared with levels in untreated treated effluents. Densities of HPC bacteria in PAC-treated effluents were significantly reduced (P < 0.01) below influent levels, however, after the point-of-use device was flushed for 2 min. While PAC significantly reduced the number of coliforms in product waters (P < 0.01), these indicator organisms were still detected in some effluents. Seasonal variations were evident in microbial counts from spring but not well water systems. It appears that aside from periods following stagnant-water use, such as overnight, PAC treatment does not compromise the bacteriological quality of drinking water obtained from underground sources. PMID:8534096

Imaging systems and algorithms to analyze biological samples in real-time using mobile phone microscopy

PubMed Central

Mayberry, Addison; Perkins, David L.; Holcomb, Daniel E.

2018-01-01

Miniaturized imaging devices have pushed the boundaries of point-of-care imaging, but existing mobile-phone-based imaging systems do not exploit the full potential of smart phones. This work demonstrates the use of simple imaging configurations to deliver superior image quality and the ability to handle a wide range of biological samples. Results presented in this work are from analysis of fluorescent beads under fluorescence imaging, as well as helminth eggs and freshwater mussel larvae under white light imaging. To demonstrate versatility of the systems, real time analysis and post-processing results of the sample count and sample size are presented in both still images and videos of flowing samples. PMID:29509786

7 CFR 51.689 - Tolerances.

Code of Federal Regulations, 2011 CFR

2011-01-01

...] Factor Grades AL 2 Number of 50-count samples 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20...) For 21 through 40 Samples [See footnotes at end of Table I] Factor Grades AL 2 Number of 50-count... United States. 2 AL—Absolute limit permitted in individual 33-count sample. 3 Sample size—33-count. 4...

7 CFR 51.689 - Tolerances.

Code of Federal Regulations, 2012 CFR

2012-01-01

...] Factor Grades AL 2 Number of 50-count samples 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20...) For 21 through 40 Samples [See footnotes at end of Table I] Factor Grades AL 2 Number of 50-count... United States. 2 AL—Absolute limit permitted in individual 33-count sample. 3 Sample size—33-count. 4...

Modification of Point Counts for Surveying Cropland Birds

Treesearch

Kathryn Freemark; Catherine Rogers

1995-01-01

As part of a comparative study of agricultural impacts on wildlife, modifications to the point count method were evaluated for surveying birds in, and adjacent to, cropland during the breeding season (May to early July) in Ontario. Location in the field, observation direction and distance, number of visits, and number of study sites per farm were examined using point...

Incidence, populations and diversity of fungi from raw materials, final products and air of processing environment of multigrain whole meal bread.

PubMed

Santos, Juliana Lane Paixão Dos; Bernardi, Angélica Olivier; Pozza Morassi, Letícia L; Silva, Beatriz S; Copetti, Marina Venturini; S Sant'Ana, Anderson

2016-09-01

This study aimed to assess the incidence, to quantify and to assess the diversity of fungi in a multigrain whole meal bread processing plant. Two hundred and eight one (n=281) samples were analyzed, including raw materials (n=120), air samples (n=136) and multigrain breads (n=25). Among the raw materials, the whole corn flour showed the highest counts of fungi (4.8logCFU/g), followed by whole-wheat flour (3.1logCFU/g). The counts of fungi in the air of processing environment were higher in post-baking steps (oven output, cooling, slicing, packaging) than in pre-baking steps (weighing and mixer) (p<0.05). Species of fungi isolated from spoiled bread samples stored at 5, 20, 25 and 30, and 40°C corresponded mostly to Penicillium paneum and Penicillium polonicum isolated from 20 and 24% of samples, respectively. These species were also isolated from raw materials (P. paneum and P. polonicum) and air collected at different processing sampling points (P. polonicum). The high counts of filamentous fungi in raw materials and air samples in processing steps such as cooling, slicing, and packaging, suggest that contamination that may occur in these steps can be critical for the shelf life of breads. The results of this study highlight that the prevention of contamination of breads by fungal spores is still a challenge for bakery industries and that other strategies such as control of germination and growth of spoilage fungi through the development of more stable formulations have to be developed. Copyright © 2016 Elsevier Ltd. All rights reserved.

A removal model for estimating detection probabilities from point-count surveys

USGS Publications Warehouse

Farnsworth, G.L.; Pollock, K.H.; Nichols, J.D.; Simons, T.R.; Hines, J.E.; Sauer, J.R.

2000-01-01

We adapted a removal model to estimate detection probability during point count surveys. The model assumes one factor influencing detection during point counts is the singing frequency of birds. This may be true for surveys recording forest songbirds when most detections are by sound. The model requires counts to be divided into several time intervals. We used time intervals of 2, 5, and 10 min to develop a maximum-likelihood estimator for the detectability of birds during such surveys. We applied this technique to data from bird surveys conducted in Great Smoky Mountains National Park. We used model selection criteria to identify whether detection probabilities varied among species, throughout the morning, throughout the season, and among different observers. The overall detection probability for all birds was 75%. We found differences in detection probability among species. Species that sing frequently such as Winter Wren and Acadian Flycatcher had high detection probabilities (about 90%) and species that call infrequently such as Pileated Woodpecker had low detection probability (36%). We also found detection probabilities varied with the time of day for some species (e.g. thrushes) and between observers for other species. This method of estimating detectability during point count surveys offers a promising new approach to using count data to address questions of the bird abundance, density, and population trends.

Microbiological hazard identification and exposure assessment of street food vending in Johannesburg, South Africa.

PubMed

Mosupye, F M; von Holy, A

2000-11-01

One hundred and thirty-two samples of beef, chicken, salad and gravy were collected from two street vendors over eleven replicate surveys to assess microbiological safety and quality. For each food type samples were collected during preparation and holding. Dish water was also collected and food preparation surfaces swabbed during preparation and display. Standard methods were used to determine aerobic plate counts, Enterobacteriaceae counts, coliform counts and spore counts. Six hundred and seventy-five predominant colonies were isolated from aerobic plate counts of all samples and characterised. The incidence of selected foodborne bacterial pathogens and non-pathogenic E. coli 1 was also determined. In most cases mean bacterial counts of the raw materials were significantly higher (P < 0.05) than those of corresponding cooked foods. No significant differences (P > 0.05) in all count types were observed between food samples collected during cooking and those collected during holding. In addition, no significant differences (P > 0.05) in all count types were observed between prepared salads and their raw materials. Mean bacterial counts of water and swab samples collected from vendor 1 were lower than those of water and swab samples collected from vendor 2.The predominant populations isolated from the aerobic plate counts were Bacillus spp., Staphylococcus spp., Enterobacteriaceae and Alcaligenes spp. Bacillus cereus was detected in 17%, Clostridium perfringens in 1%, Staphylococcus aureus in 3% and Vibrio metchnikovii in 2% of the food samples. Campylobacter jejuni, Listeria monocytogenes, and Escherichia coli O157:H7 were not detected. Non-pathogenic E. coli 1 was detected in 13% of food samples, in 86 and 36% of dish water samples collected from vendors 1 and 2, respectively, and in 36% of surface swab samples from vendor 2.

Total airborne mold particle sampling: evaluation of sample collection, preparation and counting procedures, and collection devices.

PubMed

Godish, Diana; Godish, Thad

2008-02-01

This study was conducted to evaluate (i) procedures used to collect, prepare, and count total airborne mold spore/particle concentrations, and (ii) the relative field performance of three commercially available total airborne mold spore/particle sampling devices. Differences between factory and laboratory airflow calibration values of axial fan-driven sampling instruments (used in the study) indicated a need for laboratory calibration using a mass flow meter to ensure that sample results were accurately calculated. An aniline blue-amended Calberla's solution adjusted to a pH of 4.2-4.4 provided good sample mounting/counting results using Dow Corning high vacuum grease, Dow Corning 280A adhesive, and Dow Corning 316 silicone release spray for samples collected using mini-Burkard and Allergenco samplers. Count variability among analysts was most pronounced in 5% counts of relatively low mold particle deposition density samples and trended downward with increased count percentage and particle deposition density. No significant differences were observed among means of 5, 10, and 20% counts and among analysts; a significant interaction effect was observed between analysts' counts and particle deposition densities. Significantly higher mini-Burkard and Air-O-Cell total mold spore/particle counts for 600x vs. 400x (1.9 and 2.3 x higher, respectively), 1000x vs. 600x (1.9 and 2.2 x higher, respectively) and 1000x vs. 400x (3.6 and 4.6 x higher, respectively) comparisons indicated that 1000x magnification counts best quantified total airborne mold spore/particles using light microscopy, and that lower magnification counts may result in unacceptable underreporting of airborne mold spore/particle concentrations. Modest but significantly higher (1.2x) total mold spore concentrations were observed with Allergenco vs. mini-Burkard samples collected in co-located, concurrently operated sampler studies; moderate but significantly higher mini-Burkard count values (1.4x) were observed in similar studies with Air-O-Cell samplers. These count differences were relatively small compared with the large differences observed among three count magnifications.

Establishment of reference intervals for complete blood count parameters during normal pregnancy in Beijing.

PubMed

Li, Aiwei; Yang, Shuo; Zhang, Jie; Qiao, Rui

2017-11-01

To observe the changes of complete blood count (CBC) parameters during pregnancy and establish appropriate reference intervals for healthy pregnant women. Healthy pregnant women took the blood tests at all trimesters. All blood samples were processed on Sysmex XE-2100. The following CBC parameters were analyzed: red blood cell count (RBC), hemoglobin (Hb), hematocrit (Hct), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), mean corpuscular hemoglobin concentration (MCHC), red blood cell distribution width (RDW), platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), white blood cell count (WBC), and leukocyte differential count. Reference intervals were established using the 2.5th and 97.5th percentile of the distribution. Complete blood count parameters showed dynamic changes during trimesters. RBC, Hb, Hct declined at trimester 1, reaching their lowest point at trimester 2, and began to rise again at trimester 3. WBC, neutrophil count (Neut), monocyte count (MONO), RDW, and PDW went up from trimester 1 to trimester 3. On the contrary, MCHC, lymphocyte count (LYMPH), PLT, and MPV gradually descended during pregnancy. There were statistical significances in all CBC parameters between pregnant women and normal women, regardless of the trimesters (P<.001). The median obtained were (normal vs pregnancy) as follows: RBC 4.50 vs 3.94×10 12 /L, Hb 137 vs 120 g/L, WBC 5.71 vs 9.06×10 9 /L, LYMPH% 32.2 vs 18.0, Neut% 58.7 vs 75.0, and PLT 251 vs 202×10 9 /L. The changes of CBC parameters during pregnancy are described, and reference intervals for Beijing pregnant women are demonstrated in this study. © 2017 Wiley Periodicals, Inc.

Assessing relative abundance and reproductive success of shrubsteppe raptors

USGS Publications Warehouse

Lehman, Robert N.; Carpenter, L.B.; Steenhof, Karen; Kochert, Michael N.

1998-01-01

From 1991-1994, we quantified relative abundance and reproductive success of the Ferruginous Hawk (Buteo regalis), Northern Harrier (Circus cyaneus), Burrowing Owl (Speotytoc unicularia), and Short-eared Owl (Asio flammeus) on the shrubsteppe plateaus (benchlands) in and near the Snake River Birds of Prey National Conservation Area in southwestern Idaho. To assess relative abundance, we searched randomly selected plots using four sampling methods: point counts, line transects, and quadrats of two sizes. On a persampling-effort basis, transects were slightly more effective than point counts and quadrats for locating raptor nests (3.4 pairs detected/100 h of effort vs. 2.2-3.1 pairs). Random sampling using quadrats failed to detect a Short-eared Owl population increase from 1993 to 1994. To evaluate nesting success, we tried to determine reproductive outcome for all nesting attempts located during random, historical, and incidental nest searches. We compared nesting success estimates based on all nesting attempts, on attempts found during incubation, and the Mayfield model. Most pairs used to evaluate success were pairs found incidentally. Visits to historical nesting areas yielded the highest number of pairs per sampling effort (14.6/100 h), but reoccupancy rates for most species decreased through time. Estimates based on all attempts had the highest sample sizes but probably overestimated success for all species except the Ferruginous Hawk. Estimates of success based on nesting attempts found during incubation had the lowest sample sizes. All three methods yielded biased nesting snccess estimates for the Northern Harrier and Short-eared Owl. The estimate based on pairs found during incubation probably provided the least biased estimate for the Burrowing Owl. Assessments of nesting success were hindered by difficulties in confirming egg laying and nesting success for all species except the Ferruginous hawk.

[Development of a microenvironment test chamber for airborne microbe research].

PubMed

Zhan, Ningbo; Chen, Feng; Du, Yaohua; Cheng, Zhi; Li, Chenyu; Wu, Jinlong; Wu, Taihu

2017-10-01

One of the most important environmental cleanliness indicators is airborne microbe. However, the particularity of clean operating environment and controlled experimental environment often leads to the limitation of the airborne microbe research. This paper designed and implemented a microenvironment test chamber for airborne microbe research in normal test conditions. Numerical simulation by Fluent showed that airborne microbes were evenly dispersed in the upper part of test chamber, and had a bottom-up concentration growth distribution. According to the simulation results, the verification experiment was carried out by selecting 5 sampling points in different space positions in the test chamber. Experimental results showed that average particle concentrations of all sampling points reached 10 7 counts/m 3 after 5 minutes' distributing of Staphylococcus aureus , and all sampling points showed the accordant mapping of concentration distribution. The concentration of airborne microbe in the upper chamber was slightly higher than that in the middle chamber, and that was also slightly higher than that in the bottom chamber. It is consistent with the results of numerical simulation, and it proves that the system can be well used for airborne microbe research.

Microbial Contamination and Hygiene of Fresh Cow’s Milk Produced by Smallholders in Western Zambia

PubMed Central

Knight-Jones, Theodore J.D.; Hang’ombe, M. Bernard; Songe, Mwansa M.; Sinkala, Yona; Grace, Delia

2016-01-01

A field study was performed to assess safety of smallholder fresh cow’s milk around Mongu, Western Province, Zambia. This involved observation and sampling of milk along the value chain from milking to point-of-sale and storage. Samples were collected from 86 cows, from 9 farmers, selling through two dairy cooperatives, with additional samples from informal markets. Production was very low; around one litre/day/cow and 10 L/day/herd. The milk was typically transported by bicycle in high ambient temperatures without refrigeration until reaching the point-of-sale (journey times of 30–120 min), where it was sold without pasteurisation despite milk-borne zoonoses being endemic (bovine tuberculosis (bTB) and Brucellosis). Although microbiological contamination was initially low, with geometric mean total bacterial count (TBC) of 425 cfu/mL (cfu = colony forming units) upon arrival at point-of-sale, poor hygiene led to high bacterial loads later on (geometric mean TBC > 600,000 cfu/mL after two days refrigeration), with almost all samples culture positive for Staphylococcus aureus and Escherichia coli. After milking, milk was kept for 100–223 min at temperatures favouring microbial growth (median 34 °C) and sold without a microbial kill step. In this situation limited variation in observed standards of milk hygiene had no significant effect on milk end-product bacterial counts. Options for refrigerated transport are limited. Pasteurisation at the cooperative should be investigated, as this would largely remove pathogenic microbes present in the milk whether resulting from cattle infection or poor hygiene during milking and transportation. As milk is also purchased directly from producers, on-farm milk heating options should also be assessed. Smallholders may benefit from access to national markets by providing milk to large dairies, which have systems for ensuring safety. However, this requires significant investment and an increased and more consistent supply of milk; and many consumers, unable to afford milk sold through formal sectors, would not benefit. PMID:27455294

Changes in microbial composition and the prevalence of foodborne pathogens in crab marinated in soy sauce produced by six manufacturing plants.

PubMed

Kim, Sun Ae; Choi, Eun Sook; Kim, Nam Hee; Kim, Hye Won; Lee, Na Young; Cho, Tae Jin; Jo, Jun Il; Kim, Soon Han; Lee, Soon Ho; Ha, Sang Do; Rhee, Min Suk

2017-04-01

The present study examined the changes in microbiological composition during the production process of crab marinated in soy sauce, potential microbial hazards, potential contamination routes and effective critical control points. Crab and soy sauce samples were obtained from six different manufacturing plants at different stages, and their microbiological content was comprehensively assessed by quantitative and qualitative analyses. The results revealed the following: (1) the final products contained 4.0 log colony-forming units (CFU) g -1 aerobic plate counts (APCs) and 1.1 log CFU g -1 coliforms, which may have been introduced from the raw materials (the level of APCs in raw crab and soy sauce mixed with other ingredients was 3.8 log CFU g -1 and 4.0 log CFU mL -1 respectively); (2) marination of crab in soy sauce may allow cross-contamination by coliforms; (3) only Bacillus cereus and Staphylococcus aureus were qualitatively detected in samples at different stages of manufacture (detection rate of 28 and 5.6% respectively), and these bacteria may impact the microbiological quality and safety of crab marinated in soy sauce; and (4) bacterial counts were either maintained or increased during the manufacturing process (suggesting that no particular step can be targeted to reduce bacterial counts). Proper management of raw materials and the marination process are effective critical control points, and alternative interventions may be needed to control bacterial quantity. The results provide important basic information about the production of crab marinated in soy sauce and may facilitate effective implementation of sanitary management practices in related industries and research fields. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Rapid High-Throughput Assessment of Aerobic Bacteria in Complex Samples by Fluorescence-Based Oxygen Respirometry

PubMed Central

O'Mahony, Fiach C.; Papkovsky, Dmitri B.

2006-01-01

A simple method has been developed for the analysis of aerobic bacteria in complex samples such as broth and food homogenates. It employs commercial phosphorescent oxygen-sensitive probes to monitor oxygen consumption of samples containing bacteria using standard microtiter plates and fluorescence plate readers. As bacteria grow in aqueous medium, at certain points they begin to deplete dissolved oxygen, which is seen as an increase in probe fluorescence above baseline signal. The time required to reach threshold signal is used to either enumerate bacteria based on a predetermined calibration or to assess the effects of various effectors on the growth of test bacteria by comparison with an untreated control. This method allows for the sensitive (down to a single cell), rapid (0.5 to 12 h) enumeration of aerobic bacteria without the need to conduct lengthy (48 to 72 h) and tedious colony counts on agar plates. It also allows for screening a wide range of chemical and environmental samples for their toxicity. These assays have been validated with different bacteria, including Escherichia coli, Micrococcus luteus, and Pseudomonas fluorescens, with the enumeration of total viable counts in broth and industrial food samples (packaged ham, chicken, and mince meat), and comparison with established agar plating and optical-density-at-600-nm assays has been given. PMID:16461677

Uncertainties in internal gas counting

NASA Astrophysics Data System (ADS)

Unterweger, M.; Johansson, L.; Karam, L.; Rodrigues, M.; Yunoki, A.

2015-06-01

The uncertainties in internal gas counting will be broken down into counting uncertainties and gas handling uncertainties. Counting statistics, spectrum analysis, and electronic uncertainties will be discussed with respect to the actual counting of the activity. The effects of the gas handling and quantities of counting and sample gases on the uncertainty in the determination of the activity will be included when describing the uncertainties arising in the sample preparation.

Sediment sources in the Lake Tahoe Basin, California-Nevada; preliminary results of a four-year study, August 1983-September 1987

USGS Publications Warehouse

Hill, B.R.; Hill, J.R.; Nolan, K.M.

1988-01-01

Data were collected during a 4-yr study of sediment sources in four drainage basins tributary to Lake Tahoe, California-Nevada. The study areas include the Blackwood, General, Edgewood, and Logan House Creek basins. Data include changes in bank and bed positions at channel cross sections; results of stream-channel mapping; analyses of bank and bed material samples; tabulations of bed material point counts; measured rates of hillslope erosion; dimensions of gullies; suspended-sediment data collected during synoptic snowmelt sampling; and physiographic data for the four study basins. (USGS)

CNV-CH: A Convex Hull Based Segmentation Approach to Detect Copy Number Variations (CNV) Using Next-Generation Sequencing Data

PubMed Central

De, Rajat K.

2015-01-01

Copy number variation (CNV) is a form of structural alteration in the mammalian DNA sequence, which are associated with many complex neurological diseases as well as cancer. The development of next generation sequencing (NGS) technology provides us a new dimension towards detection of genomic locations with copy number variations. Here we develop an algorithm for detecting CNVs, which is based on depth of coverage data generated by NGS technology. In this work, we have used a novel way to represent the read count data as a two dimensional geometrical point. A key aspect of detecting the regions with CNVs, is to devise a proper segmentation algorithm that will distinguish the genomic locations having a significant difference in read count data. We have designed a new segmentation approach in this context, using convex hull algorithm on the geometrical representation of read count data. To our knowledge, most algorithms have used a single distribution model of read count data, but here in our approach, we have considered the read count data to follow two different distribution models independently, which adds to the robustness of detection of CNVs. In addition, our algorithm calls CNVs based on the multiple sample analysis approach resulting in a low false discovery rate with high precision. PMID:26291322

CNV-CH: A Convex Hull Based Segmentation Approach to Detect Copy Number Variations (CNV) Using Next-Generation Sequencing Data.

PubMed

Sinha, Rituparna; Samaddar, Sandip; De, Rajat K

2015-01-01

Copy number variation (CNV) is a form of structural alteration in the mammalian DNA sequence, which are associated with many complex neurological diseases as well as cancer. The development of next generation sequencing (NGS) technology provides us a new dimension towards detection of genomic locations with copy number variations. Here we develop an algorithm for detecting CNVs, which is based on depth of coverage data generated by NGS technology. In this work, we have used a novel way to represent the read count data as a two dimensional geometrical point. A key aspect of detecting the regions with CNVs, is to devise a proper segmentation algorithm that will distinguish the genomic locations having a significant difference in read count data. We have designed a new segmentation approach in this context, using convex hull algorithm on the geometrical representation of read count data. To our knowledge, most algorithms have used a single distribution model of read count data, but here in our approach, we have considered the read count data to follow two different distribution models independently, which adds to the robustness of detection of CNVs. In addition, our algorithm calls CNVs based on the multiple sample analysis approach resulting in a low false discovery rate with high precision.

Rapid and direct detection of Invivo kinetics of pathogenic bacterial infection from mouse blood and urine.

PubMed

Gopal, Judy; Lee, Chia-Hsun; Wu, Hui-Fen

2012-06-06

This study demonstrates the first use of matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS) to trace the Invivo infection kinetics of the well known deadly pathogen Staphylococcus aureus in Swiss albino mice. The growth curve of the bacteria from the point of injection (200μL of bacterial suspension (10(8)cfu/mL)) into the mouse blood till mortality (death) was periodically analyzed using the plate counting method and MALDI-MS. Bacterial counts of 10(3)cfu/mL were observed in the log phase of the growth curve in the blood and 10(2)cfu/mL were observed in the urine samples. Death occurred in the log phase of the growth curve, where the bacterial counts showed steady increase. In other cases, the bacteria counts started decreasing after 48h and by 96h the bacteria got totally eliminated from the mouse and these mice survived. Direct MALDI-MS was not feasible for tracking the bacteria in the infected blood. However, ionic liquid 1-Butyl-3-methylimidazolium tetrafluoroborate was successful in enabling bacterial detection amidst the strong blood peaks. But, in the case of the urine analysis, it was observed that direct MALDI-MS was adequate to enable detection. The results obtained prove the efficacy of MALDI-MS for analyzing pathogenic bacteria in clinical samples. This article is part of a Special Issue entitled: Proteomics: The clinical link. Copyright © 2011 Elsevier B.V. All rights reserved.

Tender Point Count, Pain, and Mobility in the Older Population: The MOBILIZE Boston Study

PubMed Central

Eggermont, Laura H.P.; Shmerling, Robert H.; Leveille, Suzanne G.

2011-01-01

Prevalence of tender points (TP), widespread pain and fibromyalgia, as well as the relationship between TP, widespread pain and mobility was examined in 585 community-dwelling older adults (mean age 78.2 years, 63.4% female). Pain was based on location (none, single site, multisite, widespread). Mobility was measured by the Short Physical Performance Battery (SPPB), gait speed, and self-reported (S–R) mobility difficulty. Tender point count and health characteristics (i.e. BMI, chronic conditions, analgesic use, number of medications, depression, and blocks walked per week) were assessed. Results Several participants had 3 or more TP (22.1%) although prevalence of criteria-based fibromyalgia was low (0.3%). Mobility was more limited in persons with higher tender point counts. After adjustment for pain and other risk factors, higher tender point count was associated with poorer SPPB performance (score<10, aOR=1.09 per TP, 95%CI, 1.01–1.17), and slow gait speed (<0.784m/sec, aOR=1.14 per TP, 95%CI, 1.05–1.24), but not with S–R mobility difficulty. S–R mobility difficulty was associated with more disseminated pain (multisite pain, aOR=2.01, 95%CI, 1.21–3.34; widespread pain, aOR=2.47, 95%CI, 1.09–5.62). These findings portray a significant mobility burden related to tender point count and multisite and widespread pain in the older population. Future studies using longitudinal methods are warranted. PMID:19665937

Population trends, survival, and sampling methodologies for a population of Rana draytonii

USGS Publications Warehouse

Fellers, Gary M.; Kleeman, Patrick M.; Miller, David A.W.; Halstead, Brian J.

2017-01-01

Estimating population trends provides valuable information for resource managers, but monitoring programs face trade-offs between the quality and quantity of information gained and the number of sites surveyed. We compared the effectiveness of monitoring techniques for estimating population trends of Rana draytonii (California Red-legged Frog) at Point Reyes National Seashore, California, USA, over a 13-yr period. Our primary goals were to: 1) estimate trends for a focal pond at Point Reyes National Seashore, and 2) evaluate whether egg mass counts could reliably estimate an index of abundance relative to more-intensive capture–mark–recapture methods. Capture–mark–recapture (CMR) surveys of males indicated a stable population from 2005 to 2009, despite low annual apparent survival (26.3%). Egg mass counts from 2000 to 2012 indicated that despite some large fluctuations, the breeding female population was generally stable or increasing, with annual abundance varying between 26 and 130 individuals. Minor modifications to egg mass counts, such as marking egg masses, can allow estimation of egg mass detection probabilities necessary to convert counts to abundance estimates, even when closure of egg mass abundance cannot be assumed within a breeding season. High egg mass detection probabilities (mean per-survey detection probability = 0.98 [0.89–0.99]) indicate that egg mass surveys can be an efficient and reliable method for monitoring population trends of federally threatened R. draytonii. Combining egg mass surveys to estimate trends at many sites with CMR methods to evaluate factors affecting adult survival at focal populations is likely a profitable path forward to enhance understanding and conservation of R. draytonii.

Species richness and relative abundance of breeding birds in forests of the Mississippi Alluvial Valley

USGS Publications Warehouse

Nelms, C.O.; Twedt, D.J.; Smith, Winston Paul

1993-01-01

In 1992, the Vicksburg Field Research Station of the National Wetlands Research Center initiated research on the ecology of migratory birds within forests of the Mississippi Alluvial Valley (MAV). The MAV was historically a nearly contiguous bottomland hardwood forest, however, only remnants remain. These remnants are fragmented and often influenced by drainage projects, silviculture, agriculture, and urban development. Our objectives are to assess species richness and relative abundance, and to relate these to the size, quality, and composition of forest stands. Species richness and relative abundance were estimated for 53 randomly selected forest sites using 1 to 8 point counts per site, depending on the size of the forest fragment. However, statistical comparisons among sites will be restricted to an equal number ofpoint counts within the sites being compared. Point counts, lasting five minutes, were conducted from 11 May to 29 June 1992, foltowing Ralph, Sauer, and Droege (Point Count Standards; memo dated 9 March 1992). Vegetation was measured at the first three points on each site using a modification of the methods employed by Martin and Roper (Condor 90: 5 1-57; 1988). During 252 counts, 7 1 species were encountered, but only 62 species were encountered within a 50-m radius of point center. The mean number of species encountered within 50 m of a point, was 7.3 (s.d. = 2.7) and the mean number of individuals was 11.2 (s.d. = 4.2). The mean number of species detected at any distance was 9.6 (s.d, = 2.8) and the mean number of individuals was 15.6 (s.d. = 7.9). The most frequently encountered warblers in the MAV were Prothonotary Warbler and Northern Parula. Rarely encountered warblers were American Redstart and Worm-eating Warbler. The genera, Quercus, Ulmus, Carya, and Celtis were each encountered at 80 or more of the 152 points at which vegetation was sampled. Species most frequentlyencountered were: sugarberry (Celtis laevagata), water hickory (Caqa aquatica), American elm (Ulmus arnericana), sweetgum (Liquidambar styraciflua) and willow oak (Quercus phellos) The mean basal area of all trees 10 cm diameter-at-breast height (dbh) was 28 m2 /ha (range 7-70). The mean canopy cover was 87 percent, mean canopy height was 20 m, ground cover was 60 percent, and vegetation density (2-7 m) was 47 percent. The most frequently encountered understory species were sugarberry, ash (Fraxinus spp.), maple (Acer spp.), and elm (Ulnrus spp.). A cooperative GIs effort among the U.S. Fish and Wildlife Service, the Nature Conservancy, and the University of Arkansas is currently classifying forested habitats within the MAV. This effort will provide information on stand size and topology which will be used in concert with our current data, and data from visits to additional forest stands in 1993, to assess the relationship between the size, quatity, and composition of forests within the MAV and their breeding bird community.

A Calibration of NICMOS Camera 2 for Low Count Rates

NASA Astrophysics Data System (ADS)

Rubin, D.; Aldering, G.; Amanullah, R.; Barbary, K.; Dawson, K. S.; Deustua, S.; Faccioli, L.; Fadeyev, V.; Fakhouri, H. K.; Fruchter, A. S.; Gladders, M. D.; de Jong, R. S.; Koekemoer, A.; Krechmer, E.; Lidman, C.; Meyers, J.; Nordin, J.; Perlmutter, S.; Ripoche, P.; Schlegel, D. J.; Spadafora, A.; Suzuki, N.

2015-05-01

NICMOS 2 observations are crucial for constraining distances to most of the existing sample of z\\gt 1 SNe Ia. Unlike conventional calibration programs, these observations involve long exposure times and low count rates. Reciprocity failure is known to exist in HgCdTe devices and a correction for this effect has already been implemented for high and medium count rates. However, observations at faint count rates rely on extrapolations. Here instead, we provide a new zero-point calibration directly applicable to faint sources. This is obtained via inter-calibration of NIC2 F110W/F160W with the Wide Field Camera 3 (WFC3) in the low count-rate regime using z∼ 1 elliptical galaxies as tertiary calibrators. These objects have relatively simple near-IR spectral energy distributions, uniform colors, and their extended nature gives a superior signal-to-noise ratio at the same count rate than would stars. The use of extended objects also allows greater tolerances on point-spread function profiles. We find space telescope magnitude zero points (after the installation of the NICMOS cooling system, NCS) of 25.296\\+/- 0.022 for F110W and 25.803\\+/- 0.023 for F160W, both in agreement with the calibration extrapolated from count rates ≳1000 times larger (25.262 and 25.799). Before the installation of the NCS, we find 24.843\\+/- 0.025 for F110W and 25.498\\+/- 0.021 for F160W, also in agreement with the high-count-rate calibration (24.815 and 25.470). We also check the standard bandpasses of WFC3 and NICMOS 2 using a range of stars and galaxies at different colors and find mild tension for WFC3, limiting the accuracy of the zero points. To avoid human bias, our cross-calibration was “blinded” in that the fitted zero-point differences were hidden until the analysis was finalized. Based on observations with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by AURA, Inc., under NASA contract NAS 5-26555, under programs SM2/NIC-7049, SM2/NIC-7152, CAL/NIC-7607, CAL/NIC-7691, CAL/NIC-7693, GO-7887, CAL/NIC-7902, CAL/NIC-7904, GO/DD-7941, SM3/NIC-8983, SM3/NIC-8986, GTO/ACS-9290, ENG/NIC-9324, CAL/NIC-9325, GO-9352, GO-9375, SNAP-9485, CAL/NIC-9639, GO-9717, GO-9834, GO-9856, CAL/NIC-9995, CAL/NIC-9997, GO-10189, GO-10258, CAL/NIC-10381, CAL/NIC-10454, GO-10496, CAL/NIC-10725, CAL/NIC-10726, GO-10886, CAL/NIC-11060, CAL/NIC-11061, GO-11135, GO-11143, GO-11202, CAL/NIC-11319, GO/DD-11359, SM4/WFC3-11439, SM4/WFC3-11451, GO-11557, GO-11591, GO-11600, GO/DD-11799, CAL/WFC3-11921, CAL/WFC3-11926, GO/DD-12051, GO-12061, GO-12062, GO-12177, CAL/WFC3-12333, CAL/WFC3-12334, CAL/WFC3-12341, GO-12443, GO-12444, GO-12445, CAL/WFC3-12698, CAL/WFC3-12699, GO-12874, CAL/WFC3-13088, and CAL/WFC3-13089.

COMPARISON OF LABORATORY SUBSAMPLING METHODS OF BENTHIC SAMPLES FROM BOATABLE RIVERS USING ACTUAL AND SIMULATED COUNT DATA

EPA Science Inventory

We examined the effects of using a fixed-count subsample of 300 organisms on metric values using macroinvertebrate samples collected with 3 field sampling methods at 12 boatable river sites. For each sample, we used metrics to compare an initial fixed-count subsample of approxima...

Characterization of HPGe gamma spectrometric detectors systems for Instrumental Neutron Activation Analysis (INAA) at the Colombian Geological Survey

NASA Astrophysics Data System (ADS)

Sierra, O.; Parrado, G.; Cañón, Y.; Porras, A.; Alonso, D.; Herrera, D. C.; Peña, M.; Orozco, J.

2016-07-01

This paper presents the progress made by the Neutron Activation Analysis (NAA) laboratory at the Colombian Geological Survey (SGC in its Spanish acronym), towards the characterization of its gamma spectrometric systems for Instrumental Neutron Activation Analysis (INAA), with the aim of introducing corrections to the measurements by variations in sample geometry. Characterization includes the empirical determination of the interaction point of gamma radiation inside the Germanium crystal, through the application of a linear model and the use of a fast Monte Carlo N-Particle (MCNP) software to estimate correction factors for differences in counting efficiency that arise from variations in sample density between samples and standards.

Microbial quality of some vegetables sold in ED DueimTwon, Sudan.

PubMed

Goja, Arafat Mohammed; Mahmoud, Mohamed Salih Osman

2013-06-15

This study was probably the first research carried out to investigate the microbiological quality of some vegetables sold in ED DueimTwon, Sudan. Four species of vegetables were used, Arugula (Eruca sativa), Mloukhia (Corchorus olitorius), Tomato (Lycopersicon esculentum) and Green pepper (Capsicum annuum). The samples were collected and examined according to standardized methods for total viable bacteria, coliforms and fecal coliform count. The average of total viable count ranged from 1.2 x 105-5.6 x 105 CFU mL(-1) for Arugula; 2.1 x 105-2.8 x 107 CFU mL(-1) for Mloukhia; 3.4 x 105-4.8 x 105 for Tomato and 2.3 x 105-8.0 x 106 CFU mL(-1) for Green pepper. However, the maximum level of total and fecal coliform were (93, 21); (28, 11); (75, 15) and (150, 20) MPN 100 mL(-1), respectively. Twelve bacteria belonging to five genera were isolated. Staphylococcus (33%) was the most predominant isolated followed by Enterobacteriaceae (25%), Bacillus (17%) and Streptococcus (17%). Micrococcus (8%) was the least dominant isolated. The results of microbial counts of these vegetable samples in this study indicate that, the agricultural practices, harvesting, hygiene, transporting and selling points are poor and therefore, the higher microbial load could be risked for public health.

Testing the Accuracy of Aerial Surveys for Large Mammals: An Experiment with African Savanna Elephants (Loxodonta africana).

PubMed

Schlossberg, Scott; Chase, Michael J; Griffin, Curtice R

2016-01-01

Accurate counts of animals are critical for prioritizing conservation efforts. Past research, however, suggests that observers on aerial surveys may fail to detect all individuals of the target species present in the survey area. Such errors could bias population estimates low and confound trend estimation. We used two approaches to assess the accuracy of aerial surveys for African savanna elephants (Loxodonta africana) in northern Botswana. First, we used double-observer sampling, in which two observers make observations on the same herds, to estimate detectability of elephants and determine what variables affect it. Second, we compared total counts, a complete survey of the entire study area, against sample counts, in which only a portion of the study area is sampled. Total counts are often considered a complete census, so comparing total counts against sample counts can help to determine if sample counts are underestimating elephant numbers. We estimated that observers detected only 76% ± SE of 2% of elephant herds and 87 ± 1% of individual elephants present in survey strips. Detectability increased strongly with elephant herd size. Out of the four observers used in total, one observer had a lower detection probability than the other three, and detectability was higher in the rear row of seats than the front. The habitat immediately adjacent to animals also affected detectability, with detection more likely in more open habitats. Total counts were not statistically distinguishable from sample counts. Because, however, the double-observer samples revealed that observers missed 13% of elephants, we conclude that total counts may be undercounting elephants as well. These results suggest that elephant population estimates from both sample and total counts are biased low. Because factors such as observer and habitat affected detectability of elephants, comparisons of elephant populations across time or space may be confounded. We encourage survey teams to incorporate detectability analysis in all aerial surveys for mammals.

Testing the Accuracy of Aerial Surveys for Large Mammals: An Experiment with African Savanna Elephants (Loxodonta africana)

PubMed Central

Schlossberg, Scott; Chase, Michael J.; Griffin, Curtice R.

2016-01-01

Accurate counts of animals are critical for prioritizing conservation efforts. Past research, however, suggests that observers on aerial surveys may fail to detect all individuals of the target species present in the survey area. Such errors could bias population estimates low and confound trend estimation. We used two approaches to assess the accuracy of aerial surveys for African savanna elephants (Loxodonta africana) in northern Botswana. First, we used double-observer sampling, in which two observers make observations on the same herds, to estimate detectability of elephants and determine what variables affect it. Second, we compared total counts, a complete survey of the entire study area, against sample counts, in which only a portion of the study area is sampled. Total counts are often considered a complete census, so comparing total counts against sample counts can help to determine if sample counts are underestimating elephant numbers. We estimated that observers detected only 76% ± SE of 2% of elephant herds and 87 ± 1% of individual elephants present in survey strips. Detectability increased strongly with elephant herd size. Out of the four observers used in total, one observer had a lower detection probability than the other three, and detectability was higher in the rear row of seats than the front. The habitat immediately adjacent to animals also affected detectability, with detection more likely in more open habitats. Total counts were not statistically distinguishable from sample counts. Because, however, the double-observer samples revealed that observers missed 13% of elephants, we conclude that total counts may be undercounting elephants as well. These results suggest that elephant population estimates from both sample and total counts are biased low. Because factors such as observer and habitat affected detectability of elephants, comparisons of elephant populations across time or space may be confounded. We encourage survey teams to incorporate detectability analysis in all aerial surveys for mammals. PMID:27755570

Abundance of diurnal raptors on open space grasslands in an urbanized landscape

USGS Publications Warehouse

Berry, M.E.; Bock, C.E.; Haire, S.L.

1998-01-01

We conducted point counts of diurnal raptors on Boulder, Colorado, grasslands for three winters and summers, and compared results to landscape features of the count areas. Four wintering species were scarce on plots that included significant amounts of urban habitat, with a critical landscape threshold at about 5-7% urbanization: Bald Eagle (Haliaeetus leucocephalus), Ferruginous Hawk (Buteo regalis), Rough-legged Hawk (B. lagopus), and Prairie Falcon (Falco mexicanus). Counts of the first three species also were positively correlated with proximity of the count plots to the nearest colony of black-tailed prairie dogs (Cynomys ludovicianus). Two breeding species, the Red-tailed Hawk (B. jamaicensis) and Swainson's Hawk (B. swainsoni), were more abundant on plots dominated by lowland hayfields and tallgrass prairies, as opposed to upland mixed and shortgrass prairies. They, along with the ubiquitous American Kestrel (Falco sparverius), were not sensitive to the amounts of urbanization (up to 30%) that occurred in the landscapes sampled. Results of this study suggest that urban open space grasslands can support sizable populations of most diurnal raptors, as long as prey populations persist, but that some species are highly sensitive to landscape urbanization.

Microtomography with photon counting detectors: improving the quality of tomographic reconstruction by voxel-space oversampling

NASA Astrophysics Data System (ADS)

Dudak, J.; Zemlicka, J.; Karch, J.; Hermanova, Z.; Kvacek, J.; Krejci, F.

2017-01-01

Photon counting detectors Timepix are known for their unique properties enabling X-ray imaging with extremely high contrast-to-noise ratio. Their applicability has been recently further improved since a dedicated technique for assembling large area Timepix detector arrays was introduced. Despite the fact that the sensitive area of Timepix detectors has been significantly increased, the pixel pitch is kept unchanged (55 microns). This value is much larger compared to widely used and popular X-ray imaging cameras utilizing scintillation crystals and CCD-based read-out. On the other hand, photon counting detectors provide steeper point-spread function. Therefore, with given effective pixel size of an acquired radiography, Timepix detectors provide higher spatial resolution than X-ray cameras with scintillation-based devices unless the image is affected by penumbral blur. In this paper we take an advance of steep PSF of photon counting detectors and test the possibility to improve the quality of computed tomography reconstruction using finer sampling of reconstructed voxel space. The achieved results are presented in comparison with data acquired under the same conditions using a commercially available state-of-the-art CCD X-ray camera.

Effect of a Benzalkonium Chloride Surfactant-Sodium Hypochlorite Combination on Elimination of Enterococcus faecalis.

PubMed

Baron, Aleksandr; Lindsey, Kimberly; Sidow, Stephanie J; Dickinson, Douglas; Chuang, Augustine; McPherson, James C

2016-01-01

The purpose of this investigation was to determine the effect of a sodium hypochlorite-surfactant combination on the removal of Enterococcus faecalis from infected teeth. Sixty-four extracted human single canal anterior teeth were prepared with rotary instrumentation and sterilized. Teeth were divided into 4 groups, N = 16. Three experimental groups were inoculated with E. faecalis and cultured for 21 days before use: positive control group, no irrigation; NaOCl group, irrigated with 5 mL 6% NaOCl; and NaOCl/BAK group, irrigated with 5 mL 6% NaOCl/0.008% benzalkonium chloride (BAK). The negative control group received medium only and no inoculate. Paper point sampling of the canals was obtained before irrigation (S1) for all 4 groups and for 2 groups after irrigation (S2) to determine remaining colony-forming units. After sampling, all teeth were split in half and evaluated for bacterial viability colony-forming units and penetration of dentinal tubules by using fluorescent vital dye staining and confocal laser scanning microscopy. Comparison of pre-irrigation and post-irrigation paper point samples from the 2 irrigated groups showed a significant reduction in bacterial canal load (P < .001, Kruskal-Wallis), with a significantly lower load in the NaOCl/BAK group than in the NaOCl group (P = .001, Mann-Whitney U test); 68.8% of the NaOCl/BAK samples gave no recoverable counts. In contrast, no significant difference between these groups was found for counts recovered from dentin. Confocal laser scanning microscopy showed no differences in tubule penetration. The addition of BAK to NaOCl significantly reduced the number of remaining bacteria within the canal after irrigation compared with NaOCl alone. Published by Elsevier Inc.

[Yeast urinary tract infections. Multicentre study in 14 hospitals belonging to the Buenos Aires City Mycology Network].

PubMed

Maldonado, Ivana; Arechavala, Alicia; Guelfand, Liliana; Relloso, Silvia; Garbasz, Claudia

2016-01-01

Urinary tract infections are a frequent ailment in patients in intensive care units. Candida and other yeasts cause 5-12% of these infections. The value of the finding of any yeast is controversial, and there is no consensus about which parameters are adequate for differentiating urinary infections from colonization or contamination. To analyse the epidemiological characteristics of patients with funguria, to determine potential cut-off points in cultures (to distinguish an infection from other conditions), to identify the prevalent yeast species, and to determine the value of a second urine sample. A multicentre study was conducted in intensive care units of 14 hospitals in the Buenos Aires City Mycology Network. The first and second samples of urine from every patient were cultured. The presence of white cells and yeasts in direct examination, colony counts, and the identification of the isolated species, were evaluated. Yeasts grew in 12.2% of the samples. There was no statistical correlation between the number of white cells and the fungal colony-forming units. Eighty five percent of the patients had indwelling catheters. Funguria was not prevalent in women or in patients over the age of 65. Candida albicans, followed by Candida tropicalis, were the most frequently isolated yeasts. Candida parapsilosis and Candida glabrata appeared less frequently. The same species were isolated in 70% of second samples, and in 23% of the cases the second culture was negative. It was not possible to determine a useful cut-off point for colony counts to help in the diagnosis of urinary infections. As in other publications, C. albicans, followed by C. tropicalis, were the most prevalent species. Copyright © 2015 Asociación Española de Micología. Published by Elsevier Espana. All rights reserved.

A plan for the North American Bat Monitoring Program (NABat)

USGS Publications Warehouse

Loeb, Susan C.; Rodhouse, Thomas J.; Ellison, Laura E.; Lausen, Cori L.; Reichard, Jonathan D.; Irvine, Kathryn M.; Ingersoll, Thomas E.; Coleman, Jeremy; Thogmartin, Wayne E.; Sauer, John R.; Francis, Charles M.; Bayless, Mylea L.; Stanley, Thomas R.; Johnson, Douglas H.

2015-01-01

The purpose of the North American Bat Monitoring Program (NABat) is to create a continent-wide program to monitor bats at local to rangewide scales that will provide reliable data to promote effective conservation decisionmaking and the long-term viability of bat populations across the continent. This is an international, multiagency program. Four approaches will be used to gather monitoring data to assess changes in bat distributions and abundances: winter hibernaculum counts, maternity colony counts, mobile acoustic surveys along road transects, and acoustic surveys at stationary points. These monitoring approaches are described along with methods for identifying species recorded by acoustic detectors. Other chapters describe the sampling design, the database management system (Bat Population Database), and statistical approaches that can be used to analyze data collected through this program.

mrpy: Renormalized generalized gamma distribution for HMF and galaxy ensemble properties comparisons

NASA Astrophysics Data System (ADS)

Murray, Steven G.; Robotham, Aaron S. G.; Power, Chris

2018-02-01

mrpy calculates the MRP parameterization of the Halo Mass Function. It calculates basic statistics of the truncated generalized gamma distribution (TGGD) with the TGGD class, including mean, mode, variance, skewness, pdf, and cdf. It generates MRP quantities with the MRP class, such as differential number counts and cumulative number counts, and offers various methods for generating normalizations. It can generate the MRP-based halo mass function as a function of physical parameters via the mrp_b13 function, and fit MRP parameters to data in the form of arbitrary curves and in the form of a sample of variates with the SimFit class. mrpy also calculates analytic hessians and jacobians at any point, and allows the user to alternate parameterizations of the same form via the reparameterize module.

[Main concepts of preventive health care for the air staff of sea-based aviation].

PubMed

Mel'nik, S G; Chulaevskiĭ, A O

2013-08-01

The authors researched the air-stuff and complex of adverse factors uncharacteristic for the air-staff of land-based aircraft. It was determined that adverse factors affect the air-staff foremost in 4-5 months of a blue-water sailing, except cardiovascular system diseases. In a month of a blue-water sailing was registered a hypotonic state. Systolic blood pressure varied from 100-105 mm Hg and lower, dystolic blood pressure varied from 60-65 mm Hg and lower. The lowest ranges of blood pressure were registered in three months after the beginning of the sailing. In the following, the hypotonic state, registered during the monthly medical examinations, remained till the end of the sailing. Normal averages of blood pressure were restored in two weeks after the end of sailing. Low red cell count (for more than 1100 points) was registered in 61.5% of patients, (for more than 550 points) in 38.4% of patients. Low white cell count (for more than 4800 points) was registered in 33.3% of patients, (for more than 3300 points) in 41% of patients, (for more than 1330 points) in 25% of patients. Input data was: red cell count--4250 points, white cell count--7300 points in 1 ml of blood. After the sailing haematological indices were restored. The authors suggested guidelines for primary and secondary disease prevention.

A cross-sectional study of the relationship between body mass index and clinical characteristics, tenderness measures, quality of life, and physical functioning in fibromyalgia patients.

PubMed

Neumann, Lily; Lerner, Ella; Glazer, Yael; Bolotin, Arkady; Shefer, Alexander; Buskila, Dan

2008-12-01

We examined the relationship between body mass index (BMI) and measures of tenderness, quality of life, and physical functioning in female fibromyalgia (FMS) patients. A random sample of 100 female FMS patients from a database of 550 FMS individuals was interviewed and assessed according to a structured questionnaire that included FMS-related symptoms, measures of tenderness (point count and dolorimetry), quality of life (SF-36), physical functioning, and BMI. Weight was defined as normal, overweight, and obesity according to BMI. Twenty-seven percent of the FMS patients had normal BMI, 28% were overweight, and 45% were obese. BMI was negatively correlated with quality of life (r = -0.205, P = 0.044) and tenderness threshold (r = -0.238, P = 0.021) and positively correlated with physical dysfunctioning (r = 0.202, P = 0.047) and point count (r = 0.261, P = 0.011). Obese FMS patients display higher pain sensitivity and lower levels of quality of life. In designing studies that explore factors affecting tenderness, BMI should be included in addition to sex, age, etc.

Monitoring Puerto Rican avifauna using roadside surveys

USGS Publications Warehouse

Pardieck, K.L.; Peterjohn, B.G.; Ralph, C. John; Rich, Terrell D.

2005-01-01

In 1997 we began investigating the use of roadside point counts to monitor the long-term status and trends of Puerto Rican bird populations. If such a methodology proves feasible it may provide the empirical data needed for the development of sound conservation plans for the island's avifauna in much the same way that North American Breeding Bird Survey data are used by the avian conservation prioritization process of Partners in Flight, the U.S. Fish and Wildlife Service, and the Canadian Wildlife Service. By the end of the 2003 field season, we will have the data needed to quantitatively evaluate the utility of the program for tracking the population trends of Puerto Rican avifauna. Here we present data from the 2001 and 2002 field seasons to demonstrate the potential utility of these data for quantifying and portraying avian distributions, abundances, and population trend estimates. In 2001, 27 of the 44 available 5-mile roadside routes (11 stops/route) were sampled between 15 April and 15 May. At each stop a 5-minute point count was conducted. The surveys detected 5,471 individuals representing 70 species. Distribution and abundance maps are depicted for seven endemic species. In 2002, 29 routes were sampled. A total of 6,252 individuals was detected representing 79 species. Significantly fewer species and individuals were detected on wet zone routes as compared to moist and dry zone routes.

VizieR Online Data Catalog: ROSAT detected quasars. I. (Brinkmann+ 1997)

NASA Astrophysics Data System (ADS)

Brinkmann, W.; Yuan, W.

1996-09-01

We have compiled a sample of all quasars with measured radio emission from the Veron-Cetty - Veron catalogue (1993, VV93 ) detected by ROSAT in the ALL-SKY SURVEY (RASS, Voges 1992), as targets of pointed observations, or as serendipitous sources from pointed observations as publicly available from the ROSAT point source catalogue (ROSAT-SRC, Voges et al. 1995). The total number of ROSAT detected radio quasars from the above three sources is 654 objects. 69 of the objects are classified as radio-quiet using the defining line at a radio-loudness of 1.0, and 10 objects have no classification. The 5GHz data are from the 87GB radio survey, the NED database, or from the Veron-Cetty - Veron catalogue. The power law indices and their errors are estimated from the two hardness ratios given by the SASS assuming Galactic absorption. The X-ray flux densities in the ROSAT band (0.1-2.4keV) are calculated from the count rates using the energy to counts conversion factor for power law spectra and Galactic absorption. For the photon index we use the value obtained for a individual source if the estimated 1 sigma error is smaller than 0.5, otherwise we use the mean value 2.14. (1 data file).

Comparison of cell counting methods in rodent pulmonary toxicity studies: automated and manual protocols and considerations for experimental design

PubMed Central

Zeidler-Erdely, Patti C.; Antonini, James M.; Meighan, Terence G.; Young, Shih-Houng; Eye, Tracy J.; Hammer, Mary Ann; Erdely, Aaron

2016-01-01

Pulmonary toxicity studies often use bronchoalveolar lavage (BAL) to investigate potential adverse lung responses to a particulate exposure. The BAL cellular fraction is counted, using automated (i.e. Coulter Counter®), flow cytometry or manual (i.e. hemocytometer) methods, to determine inflammatory cell influx. The goal of the study was to compare the different counting methods to determine which is optimal for examining BAL cell influx after exposure by inhalation or intratracheal instillation (ITI) to different particles with varying inherent pulmonary toxicities in both rat and mouse models. General findings indicate that total BAL cell counts using the automated and manual methods tended to agree after inhalation or ITI exposure to particle samples that are relatively nontoxic or at later time points after exposure to a pneumotoxic particle when the response resolves. However, when the initial lung inflammation and cytotoxicity was high after exposure to a pneumotoxic particle, significant differences were observed when comparing cell counts from the automated, flow cytometry and manual methods. When using total BAL cell count for differential calculations from the automated method, depending on the cell diameter size range cutoff, the data suggest that the number of lung polymorphonuclear leukocytes (PMN) varies. Importantly, the automated counts, regardless of the size cutoff, still indicated a greater number of total lung PMN when compared with the manual method, which agreed more closely with flow cytometry. The results suggest that either the manual method or flow cytometry would be better suited for BAL studies where cytotoxicity is an unknown variable. PMID:27251196

Comparison of cell counting methods in rodent pulmonary toxicity studies: automated and manual protocols and considerations for experimental design.

PubMed

Zeidler-Erdely, Patti C; Antonini, James M; Meighan, Terence G; Young, Shih-Houng; Eye, Tracy J; Hammer, Mary Ann; Erdely, Aaron

2016-08-01

Pulmonary toxicity studies often use bronchoalveolar lavage (BAL) to investigate potential adverse lung responses to a particulate exposure. The BAL cellular fraction is counted, using automated (i.e. Coulter Counter®), flow cytometry or manual (i.e. hemocytometer) methods, to determine inflammatory cell influx. The goal of the study was to compare the different counting methods to determine which is optimal for examining BAL cell influx after exposure by inhalation or intratracheal instillation (ITI) to different particles with varying inherent pulmonary toxicities in both rat and mouse models. General findings indicate that total BAL cell counts using the automated and manual methods tended to agree after inhalation or ITI exposure to particle samples that are relatively nontoxic or at later time points after exposure to a pneumotoxic particle when the response resolves. However, when the initial lung inflammation and cytotoxicity was high after exposure to a pneumotoxic particle, significant differences were observed when comparing cell counts from the automated, flow cytometry and manual methods. When using total BAL cell count for differential calculations from the automated method, depending on the cell diameter size range cutoff, the data suggest that the number of lung polymorphonuclear leukocytes (PMN) varies. Importantly, the automated counts, regardless of the size cutoff, still indicated a greater number of total lung PMN when compared with the manual method, which agreed more closely with flow cytometry. The results suggest that either the manual method or flow cytometry would be better suited for BAL studies where cytotoxicity is an unknown variable.

Whey protein isolate/cellulose nanofibre/TiO2 nanoparticle/rosemary essential oil nanocomposite film: Its effect on microbial and sensory quality of lamb meat and growth of common foodborne pathogenic bacteria during refrigeration.

PubMed

Alizadeh Sani, Mahmood; Ehsani, Ali; Hashemi, Mohammad

2017-06-19

The use of biodegradable nanocomposite films in active packaging is of great importance since they can have a controlled release of antimicrobial compounds. This study was conducted to evaluate the efficacy of whey protein isolate (WPI)/cellulose nanofibre (CNF) nanocomposite films containing 1.0% (w/w) titanium dioxide (TiO 2 ) and 2.0% (w/v) rosemary essential oil (REO) in preserving the microbial and sensory quality of lamb meat during the storage at 4±1°C. Initially, the best concentration of each compound to be added to the film was determined by micro-dilution and disc diffusion methods. The microbial and sensory properties of lamb meat were controlled in two groups (control and treatment) over 15days of storage. Then, the samples were analysed for total viable count (TVC), Pseudomonas spp. count, Enterobacteriaceae count, Lactic acid bacteria (LAB) count, inoculated Staphylococcus aureus count, Listeria monocytogenes count, and Escherichia coli O 157 :H 7 count. Microbial analysis and nine-point hedonic scale was applied for the sensory analysis. Results indicated that the use of nanocomposite films significantly reduced the bacterial counts of treatment group. Higher inhibition effect was observed on Gram-positive bacteria than on Gram-negative bacteria (P<0.05). The microbial and sensory evaluations also showed that the use of nanocomposite films significantly increased the shelf life of treated meat (15days) compared to the control meat (6days). Based on the results of this study, the edible nanocomposite films were effective in preserving the microbial and sensory qualities of lamb meat; therefore, this application is recommended in meat especially red meat. Copyright © 2017 Elsevier B.V. All rights reserved.

Identification of antibiotic resistant bacteria community and a GeoChip based study of resistome in urban watersheds.

PubMed

Low, Adrian; Ng, Charmaine; He, Jianzhong

2016-12-01

Urban watersheds from point sources are potential reservoirs of antibiotic resistance genes (ARGs). However, few studies have investigated urban watersheds of non-point sources. To understand the type of ARGs and bacteria that might carry such genes, we investigated two non-point source urban watersheds with different land-use profiles. Antibiotic resistance levels of two watersheds (R1, R3) were examined using heterotrophic plate counts (HPC) as a culturing method to obtain counts of bacteria resistant to seven antibiotics belonging to different classes (erythromycin, kanamycin, lincomycin, norfloxacin, sulfanilamide, tetracycline and trimethoprim). From the HPC study, 239 antibiotic resistant bacteria were characterized for resistance to more antibiotics. Furthermore, ARGs and antimicrobial biosynthesis genes were identified using GeoChip version 5.0 to elucidate the resistomes of surface waters in watersheds R1 and R3. The HPC study showed that water samples from R1 had significantly higher counts of bacteria resistant to erythromycin, kanamycin, norfloxacin, sulfanilamide, tetracycline and trimethoprim than those from R3 (Analysis of Similarity (ANOSIM), R = 0.557, p < 0.01). Of the seven antibiotics tested, lincomycin and trimethoprim resistant bacteria are greater in abundances. The 239 antibiotic resistant isolates represent a subset of resistant bacterial populations, including bacteria not previously known for resistance. Majority of the isolates had resistance to ampicillin, vancomycin, lincomycin and trimethoprim. GeoChip revealed similar ARGs in both watersheds, but with significantly higher intensities for tetX and β-lactamase B genes in R1 than R3. The genes with the highest average normalized intensities in R1 and R3 were tetracycline (tet) and fosfomycin (fosA) resistance genes, respectively. The higher abundance of tetX genes in R1 is congruent with the higher abundance of tetracycline resistant HPC observed in R1 samples. Strong correlations (r ≥ 0.8) of efflux pumps with antimicrobial biosynthesis genes suggest that natural production of antimicrobials may act as a selective pressure of transporter proteins in the absence of antibiotics from anthropogenic sources. In conclusion, distinct antibiotic resistant bacteria phylotypes and a variety of ARGs were present in the non-point sources urban watersheds of different land-use profiles, suggesting that ARG risk assessments and monitoring studies need to include these types of watersheds. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mineral Features of EETA79001 Martian Meteorite Revealed by Point-Counting Raman Measurements as Anticipated for In-Situ Exploration on Planetary Surfaces

NASA Technical Reports Server (NTRS)

Wang, Alian; Kuebler, Karla E.; Jolliff, Brad L.

2000-01-01

The distribution of pyroxenes of different Mg' and olivines of different Fo in lithologies A and B were obtained. Three types of olivine formed at different stages of rock formation were found by point counting Raman measurements along linear traverses.

Evaluation of the Brix refractometer to estimate immunoglobulin G concentration in bovine colostrum.

PubMed

Quigley, J D; Lago, A; Chapman, C; Erickson, P; Polo, J

2013-02-01

Refractometry using a Brix refractometer has been proposed as a means to estimate IgG concentration in bovine maternal colostrum (MC). The refractometer has advantages over other methods of estimating IgG concentration in that the Brix refractometer is inexpensive, readily available, less fragile, and less sensitive to variation in colostral temperature, season of the year and other factors. Samples of first-milking MC were collected from 7 dairy farms in Maine, New Hampshire, Vermont, and Connecticut (n=84) and 1 dairy farm in California (n=99). The MC was milked from the cow at 6.1 ± 5.6h postparturition and a sample was evaluated for Brix percentage by using an optical refractometer. Two additional samples (30 mL) were collected from the milk bucket, placed in vials, and frozen before analysis of total IgG by radial immunodiffusion (RID) using commercially available plates and by turbidimetric immunoassay (TIA). The second sample was analyzed for total bacterial counts and coliform counts at laboratories in New York (Northeast samples) and California (California samples). The Brix percentage (mean ± SD) was 23.8 ± 3.5, IgG concentration measured by RID was 73.4 ± 26.2g/L, and IgG concentration measured by TIA was 67.5 ± 25.0 g/L. The Brix percentage was highly correlated (r=0.75) with IgG analyzed by RID. The Brix percentage cut point to define high- or low-quality colostrum (50 g of IgG/L measured by RID) that classified more samples correctly given the proportion of high- (86%) and low-quality (14%) samples in this study was 21%, which is slightly lower than other recent estimates of Brix measurements. At this cut point, the test sensitivity, specificity, positive and negative predictive values, and accuracy were 92.9, 65.5, 93.5, 63.3, and 88.5%, respectively. Measurement of IgG by TIA correlated with Brix (r=0.63) and RID (r=0.87); however, TIA and RID methods of IgG measurement were not consistent throughout the range of samples tested. We conclude that Brix measurement of total solids in fresh MC is an inexpensive, rapid, and satisfactorily accurate method of estimating IgG concentration. A cut point of 21% Brix to estimate samples of MC >50 g/L was most appropriate for our data. Measurement of IgG in MC by TIA differed from measurement by RID. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Particle acceleration due to shocks in the interplanetary field: High time resolution data and simulation results

NASA Technical Reports Server (NTRS)

Kessel, R. L.; Armstrong, T. P.; Nuber, R.; Bandle, J.

1985-01-01

Data were examined from two experiments aboard the Explorer 50 (IMP 8) spacecraft. The Johns Hopkins University/Applied Lab Charged Particle Measurement Experiment (CPME) provides 10.12 second resolution ion and electron count rates as well as 5.5 minute or longer averages of the same, with data sampled in the ecliptic plane. The high time resolution of the data allows for an explicit, point by point, merging of the magnetic field and particle data and thus a close examination of the pre- and post-shock conditions and particle fluxes associated with large angle oblique shocks in the interplanetary field. A computer simulation has been developed wherein sample particle trajectories, taken from observed fluxes, are allowed to interact with a planar shock either forward or backward in time. One event, the 1974 Day 312 shock, is examined in detail.

A microfluidic biochip platform for electrical quantification of proteins.

PubMed

Valera, Enrique; Berger, Jacob; Hassan, Umer; Ghonge, Tanmay; Liu, Julia; Rappleye, Michael; Winter, Jackson; Abboud, Daniel; Haidry, Zeeshan; Healey, Ryan; Hung, Na-Teng; Leung, Nathaniel; Mansury, Naif; Hasnain, Alexander; Lannon, Christine; Price, Zachary; White, Karen; Bashir, Rashid

2018-05-15

Sepsis, an adverse auto-immune response to an infection often causing life-threatening complications, results in the highest mortality and treatment cost of any illness in US hospitals. Several immune biomarker levels, including Interleukin 6 (IL-6), have shown a high correlation to the onset and progression of sepsis. Currently, no technology diagnoses and stratifies sepsis progression using biomarker levels. This paper reports a microfluidic biochip platform to detect proteins in undiluted human plasma samples. The device uses a differential enumeration platform that integrates Coulter counting principles, antigen specific capture chambers, and micro size bead based immunodetection to quantify cytokines. This microfluidic biochip was validated as a potential point of care technology by quantifying IL-6 from plasma samples (n = 29) with good correlation (R2 = 0.81) and agreement (Bland-Altman) compared to controls. In combination with previous applications, this point of care platform can potentially detect cell and protein biomarkers simultaneously for sepsis stratification.

Water quality in Lake Lanier

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

Callaham, M.A.

1991-04-01

Thirteen water quality tests measuring five categories of pollution were conducted twice monthly from May, 1987 to April, 1990 at eight locations on Lake Sidney Lanier to establish baseline data and detect trends. Additionally, sediment and water samples were analyzed for ten toxic metals. Sampling stations were located at or near the point of entry of streams into the Lake. Oxygen demanding pollutants were highest in urban streams and phosphorus and nitrogen concentrations were highest in streams having poultry processing operations within their watersheds. Indicators of siltation increased coincidentally with highway construction in one watershed. Fecal coliform bacteria counts decreasedmore » at Flat Creek and increased in the Chattahoochee River. Zinc and copper occurred in water samples at levels of detectability. Sediment samples from several locations contained metal concentrations which warrant further study.« less

Microbiological survey of a South African poultry processing plant.

PubMed

Geornaras, I; de Jesus, A; van Zyl, E; von Holy, A

1995-01-01

Bacterial populations associated with poultry processing were determined on neck skin samples, equipment surfaces and environmental samples by replicate surveys. Aerobic plate counts, Enterobacteriaceae counts, Enterobacteriaceae counts and Pseudomonas counts were performed by standard procedures and the prevalence of Listeria, presumptive Salmonella and Staphylococcus aureus determined. Statistically significant (P < 0.05) increases in counts of all types of bacteria were obtained on product samples as a result of processing. Although bacterial counts on neck skin samples decreased by 0.3 to 0.4 log CFU g-1 after spray washing of carcasses, subsequent spinchilling and packaging of whole carcasses resulted in 0.7 to 1.2 log CFU g-1 increases. Bacterial numbers on equipment surfaces, however, decreased significantly from the "dirty" to the "clean" areas of the abattoir. Transport cages, "rubber fingers", defeathering curtains, shackles and conveyor belts repeatedly showed aerobic plate counts in excess of 5.0 log CFU 25 cm-2. Aerobic plate counts of scald tank and spinchiller water were 2 log CFU ml-1 higher than those of potable water samples. Bacterial numbers of the air in the "dirty" area were higher than those of the "clean" area. Listeria, presumptive Salmonella and Staphylococcus aureus were isolated from 27.6, 51.7 and 24.1% of all product samples, respectively, and Listeria and Staphylococcus aureus were also isolated from selected equipment surfaces.

Quality evaluation of processed clay soil samples.

PubMed

Steiner-Asiedu, Matilda; Harrison, Obed Akwaa; Vuvor, Frederick; Tano-Debrah, Kwaku

2016-01-01

This study assessed the microbial quality of clay samples sold on two of the major Ghanaian markets. The study was a cross-sectional assessing the evaluation of processed clay and effects it has on the nutrition of the consumers in the political capital town of Ghana. The items for the examination was processed clay soil samples. Staphylococcus spp and fecal coliforms including Klebsiella, Escherichia, and Shigella and Enterobacterspp were isolated from the clay samples. Samples from the Kaneshie market in Accra recorded the highest total viable counts 6.5 Log cfu/g and Staphylococcal count 5.8 Log cfu/g. For fecal coliforms, Madina market samples had the highest count 6.5 Log cfu/g and also recorded the highest levels of yeast and mould. For Koforidua, total viable count was highest in the samples from the Zongo market 6.3 Log cfu/g. Central market samples had the highest count of fecal coliforms 4.6 Log cfu/g and yeasts and moulds 6.5 Log cfu/g. "Small" market recorded the highest staphylococcal count 6.2 Log cfu/g. The water activity of the clay samples were low, and ranged between 0.65±0.01 and 0.66±0.00 for samples collected from Koforidua and Accra respectively. The clay samples were found to contain Klebsiella spp. Escherichia, Enterobacter, Shigella spp. staphylococcus spp., yeast and mould. These have health implications when consumed.

Accuracy of Automated Flow Cytometry-Based Leukocyte Counts To Rule Out Urinary Tract Infection in Febrile Children: a Prospective Cross-Sectional Study

PubMed Central

Duong, Hong Phuoc; Wissing, Karl Martin; Tram, Nathalie; Mascart, Georges; Lepage, Philippe

2016-01-01

Automated flow cytometry of urine remains an incompletely validated method to rule out urinary tract infection (UTI) in children. This cross-sectional analytical study was performed to compare the predictive values of flow cytometry and a dipstick test as initial diagnostic tests for UTI in febrile children and prospectively included 1,106 children (1,247 episodes). Urine culture was used as the gold standard test for diagnosing UTI. The performance of screening tests to diagnose UTI were established using receiver operating characteristic (ROC) analysis. Among these 1,247 febrile episodes, 221 UTIs were diagnosed (17.7% [95% confidence interval {CI}, 15.6 to 19.8%]). The area under the ROC curve for flow cytometry white blood cell (WBC) counts (0.99 [95% CI, 0.98 to 0.99]) was significantly superior to that for red blood cell (0.74 [95% CI, 0.70 to 0.78]) and bacterial counts (0.89 [95% CI, 0.87 to 0.92]) (P < 0.001). Urinary WBC counts also had a significantly higher area under the ROC curve than that of the leukocyte esterase (LE) dipstick (0.92 [95% CI, 0.90 to 0.94]), nitrite dipstick (0.83 [95% CI, 0.80 to 0.87]), or the combination of positive LE and/or nitrite dipstick (0.91 [95% CI, 0.89 to 0.93]) test (P < 0.001). The presence of ≥35 WBC/μl of urine was the best cutoff point, yielding both a high sensitivity (99.5% [95% CI, 99 to 100%]) and an acceptable specificity (80.6% [95% CI, 78 to 83%]). Using this cutoff point would have reduced the number of samples sent to the laboratory for culture by 67%. In conclusion, the determination of urinary WBC counts by flow cytometry provides optimal performance as an initial diagnostic test for UTI in febrile children. PMID:27682127

Aerobic Mesophilic, Coliform, Escherichia coli, and Staphylococcus aureus Counts of Raw Meat from the Formal and Informal Meat Sectors in South Africa

PubMed Central

Muchenje, Voster

2018-01-01

Foodborne disease (FBD) is a global public health concern, and foods from animal sources have been associated with outbreaks of food-related illness. In this study, animal carcasses from the two abattoirs (HT1 and HT2) in the formal meat sector (FMS) and slaughter points in the informal meat sector (INMS) were examined at two stages of slaughter (before washing and after washing) for aerobic colony counts (ACC) and total viable count (TCC), as well as Escherichia coli and Staphylococcus aureus count. At each stage, carcasses were sampled by swabbing at the neck, brisket, flank, and rump. ACC for beef, mutton, and pork carcasses at HT1 and HT2 before washing were between 2.5–5.8, 2.2–4.7, and 2.7–3.7 mean log CFU/cm2, respectively, and TCC count before washing was highest on the neck of cattle (6.3 ± 2.4) and after washing was highest on the perineal of sheep (5.7 ± 6.9). In the INMS, TCC count was highest on the brisket (6.9 ± 3.2) and in the neck (5.5 ± 2.4). Higher ACC values of 6.2–6.7 mean log CFU/cm2 were obtained in the INMS. The highest count for E. coli (4.2 mean log CFU/cm2) after washing was in the neck, while the highest count for S. aureus (4.0 mean log CFU/cm2) was in the flank. All bacteria count in the INMS exceeded acceptable limits, and washing did not significantly reduce microbial load in meat in the FMS and INMS. Bacteria count in the FMS and INMS exceeded acceptable standards. However, meat processed in the INMS poses a more significant risk of FBD to consumers. PMID:29690529

Accurate live and dead bacterial cell enumeration using flow cytometry (Conference Presentation)

NASA Astrophysics Data System (ADS)

Ou, Fang; McGoverin, Cushla; Swift, Simon; Vanholsbeeck, Frédérique

2017-03-01

Flow cytometry (FCM) is based on the detection of scattered light and fluorescence to identify cells with particular characteristics of interest. However most FCM cannot precisely control the flow through its interrogation point and hence the volume and concentration of the sample cannot be immediately obtained. The easiest, most reliable and inexpensive way of obtaining absolute counts with FCM is by using reference beads. We investigated a method of using FCM with reference beads to measure live and dead bacterial concentration over the range of 106 to 108 cells/mL and ratio varying from 0 to 100%. We believe we are the first to use this method for such a large cell concentration range while also establishing the effect of varying the live/dead bacteria ratios. Escherichia coli solutions with differing ratios of live:dead cells were stained with fluorescent dyes SYTO 9 and propidium iodide (PI), which label live and dead cells, respectively. Samples were measured using a LSR II Flow Cytometer (BD Biosciences); using 488 nm excitation with 20 mW power. Both SYTO 9 and PI fluorescence were collected and threshold was set to side scatter. Traditional culture-based plate count was done in parallel to the FCM analysis. The concentration of live bacteria from FCM was compared to that obtained by plate counts. Preliminary results show that the concentration of live bacteria obtained by FCM and plate counts correlate well with each other and indicates this may be extended to a wider concentration range or for studying other cell characteristics.

Changes in the Microbial Composition of Microbrewed Beer during the Process in the Actual Manufacturing Line.

PubMed

Kim, S A; Jeon, S H; Kim, N H; Kim, H W; Lee, N Y; Cho, T J; Jung, Y M; Lee, S H; Hwang, I G; Rhee, M S

2015-12-01

This study investigated changes in the microbial composition of microbrewed beer during the manufacturing processes and identified potential microbial hazards, effective critical quality control points, and potential contamination routes. Comprehensive quantitative (aerobic plate count, lactic acid bacteria, fungi, acetic acid bacteria, coliforms, and Bacillus cereus) and qualitative (Escherichia coli and eight foodborne pathogens) microbiological analyses were performed using samples of raw materials (malt and manufacturing water), semiprocessed products (saccharified wort, boiled wort, and samples taken during the fermentation and maturation process), and the final product obtained from three plants. The initial aerobic plate count and lactic acid bacteria counts in malt were 5.2 and 4.3 log CFU/g, respectively. These counts were reduced to undetectable levels by boiling but were present at 2.9 and 0.9 log CFU/ml in the final product. Fungi were initially present at 3.6 log CFU/g, although again, the microbes were eliminated by boiling; however, the level in the final product was 4.6 log CFU/ml. No E. coli or foodborne pathogens (except B. cereus) were detected. B. cereus was detected at all stages, although it was not present in the water or boiled wort (total detection rate ¼ 16.4%). Results suggest that boiling of the wort is an effective microbial control measure, but careful management of raw materials and implementation of effective control measures after boiling are needed to prevent contamination of the product after the boiling step. The results of this study may constitute useful and comprehensive information regarding the microbiological quality of microbrewed beer.

A prospective study of marine phytoplankton and reported ...

EPA Pesticide Factsheets

BACKGROUND: Blooms of marine phytoplankton may adversely affect human health. The potential public health impact of low-level exposures is not well established, and few prospective cohort studies of recreational exposures to marine phytoplankton have been conducted.OBJECTIVE: We evaluated the association between phytoplankton cell counts and subsequent illness among recreational beachgoers.METHODS:We recruited beachgoers at Boquer6n Beach, Puerto Rico, during the summer of 2009. We conducted interviews at three time points to assess baseline health, water activities, and subsequent illness. Daily water samples were quantitatively assayed for phytoplankton cell count. Logistic regression models, adjusted for age and sex, were used to assess the association between exposure to three categories of phytoplankton concentration and subsequent illness.RESULTS: During 26 study days, 15,726 individuals successfully completed all three interviews. Daily total phytoplankton cell counts ranged from 346 to 2,012 cells/ml (median, 712 cells/ml). The category with the highest (≥75th percentile) total phytoplankton cell count was associated with eye irritation [adjusted odds ratio (OR) = 1.30; 95% confidence interval (Cl): 1.01, 1.66], rash (OR = 1.27; 95% Cl: 1.02, 1.57), and earache (OR = 1.25; 95% Cl: 0.88, 1.77). In phytoplankton group-specific analyses, the category with the highest Cyanobacteria counts was associated with respiratory illness (OR = 1.37; 95% Cl: 1.12, 1

Effectiveness of physical activity intervention among government employees with metabolic syndrome.

PubMed

Huei Phing, Chee; Abu Saad, Hazizi; Barakatun Nisak, M Y; Mohd Nasir, M T

2017-12-01

Our study aimed to assess the effects of physical activity interventions via standing banners (point-of-decision prompt) and aerobics classes to promote physical activity among individuals with metabolic syndrome. We conducted a cluster randomized controlled intervention trial (16-week intervention and 8-week follow-up). Malaysian government employees in Putrajaya, Malaysia, with metabolic syndrome were randomly assigned by cluster to a point-of-decision prompt group (n = 44), an aerobics group (n = 42) or a control group (n = 103) based on sample size calculation formula. Step counts were evaluated by Lifecorder e-STEP accelerometers for all participants. Metabolic syndrome was defined according to the 'harmonizing' definition, in which individuals who have at least three of the five metabolic risk factors (waist circumference, high-density lipoprotein cholesterol, triglycerides, fasting glucose levels, systolic and diastolic blood pressure) will be classified as having metabolic syndrome. A total of 80% of the enrolled government employees with metabolic syndrome completed the programme. Data were analyzed using SPSS for Windows (version 20, SPSS, Chicago, IL). There were significantly higher step counts on average in the aerobics group compared to the control group over assessments. Assessments at baseline, post-intervention and follow-up showed a significant difference in step counts between the intervention and control groups. The greatest reductions in the proportions of individuals with metabolic syndrome were observed in the aerobics group with a reduction of 79.4% in the post-intervention assessment compared to the assessment at baseline. The findings of this study suggest that physical activity intervention via aerobics classes is an effective strategy for improving step counts and reducing the prevalence of metabolic syndrome.

Concordance of anaplastic lymphoma kinase (ALK) gene rearrangements between circulating tumor cells and tumor in non-small cell lung cancer

PubMed Central

Lim, Tony KH; Tan, Daniel Shao-Weng; Chua, Yong Wei; Ang, Mei Kim; Pang, Brendan; Lim, Chwee Teck; Takano, Angela; Lim, Alvin Soon-Tiong; Leong, Man Chun; Lim, Wan-Teck

2016-01-01

Anaplastic lymphoma kinase (ALK) gene rearrangement in non-small cell lung cancer (NSCLC) is routinely evaluated by fluorescent in-situ hybridization (FISH) testing on biopsy tissues. Testing can be challenging however, when suitable tissue samples are unavailable. We examined the relevance of circulating tumor cells (CTC) as a surrogate for biopsy-based FISH testing. We assessed paired tumor and CTC samples from patients with ALK rearranged lung cancer (n = 14), ALK-negative lung cancer (n = 12), and healthy controls (n = 5) to derive discriminant CTC counts, and to compare ALK rearrangement patterns. Blood samples were enriched for CTCs to be used for ALK FISH testing. ALK-positive CTCs counts were higher in ALK-positive NSCLC patients (3–15 cells/1.88 mL of blood) compared with ALK-negative NSCLC patients and healthy donors (0–2 cells/1.88 mL of blood). The latter range was validated as the ‘false positive’ cutoff for ALK FISH testing of CTCs. ALK FISH signal patterns observed on tumor biopsies were recapitulated in CTCs in all cases. Sequential CTC counts in an index case of lung cancer with no evaluable tumor tissue treated with crizotinib showed six, three and eleven ALK-positive CTCs per 1.88 mL blood at baseline, partial response and post-progression time points, respectively. Furthermore, ALK FISH rearrangement suggestive of gene copy number increase was observed in CTCs following progression. Recapitulation of ALK rearrangement patterns in the tumor on CTCs, suggested that CTCs might be used to complement tissue-based ALK testing in NSCLC to guide ALK-targeted therapy when suitable tissue biopsy samples are unavailable for testing. PMID:26993609

Microbial quality and associated health risks of raw milk marketed in the Tanga region of Tanzania.

PubMed

Swai, E S; Schoonman, L

2011-06-01

To evaluate microbial quality and associated health risks of raw milk marketed in the Tanga region of Tanzania. A microbial quality assessment of marketed raw milk was undertaken by evaluating 59 samples of milk from selling points (collecting centres =15), bicycle boys (12) and kiosks/restaurants (32) in Tanga city during April-May 2005. Quality and milk-borne hazards were assessed using a combination of tests in order to quantify the occurrence of Brucellosis (milk ring test), Escherichia coli (E. coli) O157:H7 (culture), the coliform bacteria as well as standard plate count (SPC). Specific gravity (SG) determination was used as an indicator of adulteration. The mean coliform plate count (c.f.u/mL) of milk handled by bicycle boys (4.2×10(6)) was significantly higher than that handled by collecting centres (3.0×10(6)) and kiosk/ restaurants (1.4×10(6)), respectively (P < 0.05). Of the 59 milk samples collected, 33 (56%) were Brucella milk ring test (MRT)-positive and 78% and 17% of the samples graded satisfactorily based on SG and coliform plate counts as prescribed by East African Community standards for raw milk. There was no verocytotoxigenic E. coli (VTEC) O157: H7 in any of the milk samples collected and analysed during the present study. It can be concluded that raw market milk in the study area is of poor bacteriological quality and hazardous for human consumption. This highlights the need to implement good hygiene practices and effective monitoring from production through the delivery chain to the consumer. Further studies are needed for detection of toxins that are produced by E. coli, other pathogenic spore forming bacteria (Bacillus spp. and Clostridium spp.) and other harmful microorganisms.

Assessing paleo-biodiversity using low proxy influx.

PubMed

Blarquez, Olivier; Finsinger, Walter; Carcaillet, Christopher

2013-01-01

We developed an algorithm to improve richness assessment based on paleoecological series, considering sample features such as their temporal resolutions or their volumes. Our new method can be applied to both high- and low-count size proxies, i.e. pollen and plant macroremain records, respectively. While pollen generally abounds in sediments, plant macroremains are generally rare, thus leading to difficulties to compute paleo-biodiversity indices. Our approach uses resampled macroremain influxes that enable the computation of the rarefaction index for the low influx records. The raw counts are resampled to a constant resolution and sample volume by interpolating initial sample ages at a constant time interval using the age∼depth model. Then, the contribution of initial counts and volume to each interpolated sample is determined by calculating a proportion matrix that is in turn used to obtain regularly spaced time series of pollen and macroremain influx. We applied this algorithm to sedimentary data from a subalpine lake situated in the European Alps. The reconstructed total floristic richness at the study site increased gradually when both pollen and macroremain records indicated a decrease in relative abundances of shrubs and an increase in trees from 11,000 to 7,000 cal BP. This points to an ecosystem change that favored trees against shrubs, whereas herb abundance remained stable. Since 6,000 cal BP, local richness decreased based on plant macroremains, while pollen-based richness was stable. The reconstructed richness and evenness are interrelated confirming the difficulty to distinguish these two aspects for the studies in paleo-biodiversity. The present study shows that low-influx bio-proxy records (here macroremains) can be used to reconstruct stand diversity and address ecological issues. These developments on macroremain and pollen records may contribute to bridge the gap between paleoecology and biodiversity studies.

Concordance of anaplastic lymphoma kinase (ALK) gene rearrangements between circulating tumor cells and tumor in non-small cell lung cancer.

PubMed

Tan, Chye Ling; Lim, Tse Hui; Lim, Tony Kh; Tan, Daniel Shao-Weng; Chua, Yong Wei; Ang, Mei Kim; Pang, Brendan; Lim, Chwee Teck; Takano, Angela; Lim, Alvin Soon-Tiong; Leong, Man Chun; Lim, Wan-Teck

2016-04-26

Anaplastic lymphoma kinase (ALK) gene rearrangement in non-small cell lung cancer (NSCLC) is routinely evaluated by fluorescent in-situ hybridization (FISH) testing on biopsy tissues. Testing can be challenging however, when suitable tissue samples are unavailable. We examined the relevance of circulating tumor cells (CTC) as a surrogate for biopsy-based FISH testing. We assessed paired tumor and CTC samples from patients with ALK rearranged lung cancer (n = 14), ALK-negative lung cancer (n = 12), and healthy controls (n = 5) to derive discriminant CTC counts, and to compare ALK rearrangement patterns. Blood samples were enriched for CTCs to be used for ALK FISH testing. ALK-positive CTCs counts were higher in ALK-positive NSCLC patients (3-15 cells/1.88 mL of blood) compared with ALK-negative NSCLC patients and healthy donors (0-2 cells/1.88 mL of blood). The latter range was validated as the 'false positive' cutoff for ALK FISH testing of CTCs. ALK FISH signal patterns observed on tumor biopsies were recapitulated in CTCs in all cases. Sequential CTC counts in an index case of lung cancer with no evaluable tumor tissue treated with crizotinib showed six, three and eleven ALK-positive CTCs per 1.88 mL blood at baseline, partial response and post-progression time points, respectively. Furthermore, ALK FISH rearrangement suggestive of gene copy number increase was observed in CTCs following progression. Recapitulation of ALK rearrangement patterns in the tumor on CTCs, suggested that CTCs might be used to complement tissue-based ALK testing in NSCLC to guide ALK-targeted therapy when suitable tissue biopsy samples are unavailable for testing.

Designing and implementing a monitoring program and the standards for conducting point counts

Treesearch

C. John Ralph

1993-01-01

Choosing between the apparent plethora of methods for monitoring bird populations is a dilemma for a person contemplating beginning a monitoring program. Cooperrider et al. (1986) and Koskimies and Vaisanen (1991) describe many methods. In the Americas, three methods have been suggested as standard (Butcher 1992). They are: point counts for determining habitat...

High-mountain lakes provide a seasonal niche for migrant American dippers

Treesearch

J. M. Garwood; K. L. Pope; R. M. Bourque; M. D. Larson

2009-01-01

We studied summer use of high elevation lakes by American Dippers (Cinclus mexicanus) in the Trinity Alps Wilderness, California by conducting repeated point-count surveys at 16 study lakes coupled with a 5-year detailed survey of all available aquatic habitats in a single basin. We observed American Dippers during 36% of the point-count surveys...

A Land Manager's Guide to Point Counts of Birds in the Southeast

Treesearch

Paul B. Hamel; Winston P. Smith; Daniel J. Twedt; James R. Woehr; Eddie Morris; Robert B. Hamilton; Robert J. Cooper

1996-01-01

Current widespread concern for the status of neotropical migratory birds has sparked interest in techniques for inventorying and monitoring populations of these and other birds in southeastern forest habitats. The present guide gives detailed instructions for conducting point counts of birds. It further presents a detailed methodology for the design and conduct of...

CD4 Lymphocyte Enumeration and Hemoglobin Assessment Aid for Priority Decisions: A Multisite Evaluation of the BD FACSPresto™ System

PubMed Central

Thakar, Madhuri; Angira, Francis; Pattanapanyasat, Kovit; Wu, Alan H.B.; O’Gorman, Maurice; Zeng, Hui; Qu, Chenxue; Mahajan, Bharati; Sukapirom, Kasama; Chen, Danying; Hao, Yu; Gong, Yan; Indig, Monika De Arruda; Graminske, Sharon; Orta, Diana; d’Empaire, Nicole; Lu, Beverly; Omana-Zapata, Imelda; Zeh, Clement

2017-01-01

Background: The BD FACSPresto™ system uses capillary and venous blood to measure CD4 absolute counts (CD4), %CD4 in lymphocytes, and hemoglobin (Hb) in approximately 25 minutes. CD4 cell count is used with portable CD4 counters in resource-limited settings to manage HIV/AIDS patients. A method comparison was performed using capillary and venous samples from seven clinical laboratories in five countries. The BD FACSPresto system was assessed for variability between laboratory, instrument/operators, cartridge lots and within-run at four sites. Methods: Samples were collected under approved voluntary consent. EDTA-anticoagulated venous samples were tested for CD4 and %CD4 T cells using the gold-standard BD FACSCalibur™ system, and for Hb, using the Sysmex® KX-21N™ analyzer. Venous and capillary samples were tested on the BD FACSPresto system. Matched data was analyzed for bias (Deming linear regression and Bland-Altman methods), and for concordance around the clinical decision point. The coefficient of variation was estimated per site, instrument/operator, cartridge-lot and between-runs. Results: For method comparison, 93% of the 720 samples were from HIV-positive and 7% from HIV-negative or normal subjects. CD4 and %CD4 T cells venous and capillary results gave slopes within 0.96–1.05 and R2 ≥0.96; Hb slopes were ≥1.00 and R2 ≥0.89. Variability across sites/operators gave %CV <5.8% for CD4 counts, <1.9% for %CD4 and <3.2% for Hb. The total %CV was <7.7% across instrument/cartridge lot. Conclusion: The BD FACSPresto system provides accurate, reliable, precise CD4/%CD4/Hb results compared to gold-standard methods, irrespective of venous or capillary blood sampling. The data showed good agreement between the BD FACSPresto, BD FACSCalibur and Sysmex systems. PMID:29290885

CD4 Lymphocyte Enumeration and Hemoglobin Assessment Aid for Priority Decisions: A Multisite Evaluation of the BD FACSPresto™ System.

PubMed

Thakar, Madhuri; Angira, Francis; Pattanapanyasat, Kovit; Wu, Alan H B; O'Gorman, Maurice; Zeng, Hui; Qu, Chenxue; Mahajan, Bharati; Sukapirom, Kasama; Chen, Danying; Hao, Yu; Gong, Yan; Indig, Monika De Arruda; Graminske, Sharon; Orta, Diana; d'Empaire, Nicole; Lu, Beverly; Omana-Zapata, Imelda; Zeh, Clement

2017-01-01

The BD FACSPresto ™ system uses capillary and venous blood to measure CD4 absolute counts (CD4), %CD4 in lymphocytes, and hemoglobin (Hb) in approximately 25 minutes. CD4 cell count is used with portable CD4 counters in resource-limited settings to manage HIV/AIDS patients. A method comparison was performed using capillary and venous samples from seven clinical laboratories in five countries. The BD FACSPresto system was assessed for variability between laboratory, instrument/operators, cartridge lots and within-run at four sites. Samples were collected under approved voluntary consent. EDTA-anticoagulated venous samples were tested for CD4 and %CD4 T cells using the gold-standard BD FACSCalibur ™ system, and for Hb, using the Sysmex ® KX-21N ™ analyzer. Venous and capillary samples were tested on the BD FACSPresto system. Matched data was analyzed for bias (Deming linear regression and Bland-Altman methods), and for concordance around the clinical decision point. The coefficient of variation was estimated per site, instrument/operator, cartridge-lot and between-runs. For method comparison, 93% of the 720 samples were from HIV-positive and 7% from HIV-negative or normal subjects. CD4 and %CD4 T cells venous and capillary results gave slopes within 0.96-1.05 and R 2 ≥0.96; Hb slopes were ≥1.00 and R 2 ≥0.89. Variability across sites/operators gave %CV <5.8% for CD4 counts, <1.9% for %CD4 and <3.2% for Hb. The total %CV was <7.7% across instrument/cartridge lot. The BD FACSPresto system provides accurate, reliable, precise CD4/%CD4/Hb results compared to gold-standard methods, irrespective of venous or capillary blood sampling. The data showed good agreement between the BD FACSPresto, BD FACSCalibur and Sysmex systems.

Double sampling to estimate density and population trends in birds

USGS Publications Warehouse

Bart, Jonathan; Earnst, Susan L.

2002-01-01

We present a method for estimating density of nesting birds based on double sampling. The approach involves surveying a large sample of plots using a rapid method such as uncorrected point counts, variable circular plot counts, or the recently suggested double-observer method. A subsample of those plots is also surveyed using intensive methods to determine actual density. The ratio of the mean count on those plots (using the rapid method) to the mean actual density (as determined by the intensive searches) is used to adjust results from the rapid method. The approach works well when results from the rapid method are highly correlated with actual density. We illustrate the method with three years of shorebird surveys from the tundra in northern Alaska. In the rapid method, surveyors covered ~10 ha h-1 and surveyed each plot a single time. The intensive surveys involved three thorough searches, required ~3 h ha-1, and took 20% of the study effort. Surveyors using the rapid method detected an average of 79% of birds present. That detection ratio was used to convert the index obtained in the rapid method into an essentially unbiased estimate of density. Trends estimated from several years of data would also be essentially unbiased. Other advantages of double sampling are that (1) the rapid method can be changed as new methods become available, (2) domains can be compared even if detection rates differ, (3) total population size can be estimated, and (4) valuable ancillary information (e.g. nest success) can be obtained on intensive plots with little additional effort. We suggest that double sampling be used to test the assumption that rapid methods, such as variable circular plot and double-observer methods, yield density estimates that are essentially unbiased. The feasibility of implementing double sampling in a range of habitats needs to be evaluated.

Mapping the acquisition of the number word sequence in the first year of school

NASA Astrophysics Data System (ADS)

Gould, Peter

2017-03-01

Learning to count and to produce the correct sequence of number words in English is not a simple process. In NSW government schools taking part in Early Action for Success, over 800 students in each of the first 3 years of school were assessed every 5 weeks over the school year to determine the highest correct oral count they could produce. Rather than displaying a steady increase in the accurate sequence of the number words produced, the kindergarten data reported here identified clear, substantial hurdles in the acquisition of the counting sequence. The large-scale, longitudinal data also provided evidence of learning to count through the teens being facilitated by the semi-regular structure of the number words in English. Instead of occurring as hurdles to starting the next counting sequence, number words corresponding to some multiples of ten (10, 20 and 100) acted as if they were rest points. These rest points appear to be artefacts of how the counting sequence is acquired.

Quality evaluation of processed clay soil samples

PubMed Central

Steiner-Asiedu, Matilda; Harrison, Obed Akwaa; Vuvor, Frederick; Tano-Debrah, Kwaku

2016-01-01

Introduction This study assessed the microbial quality of clay samples sold on two of the major Ghanaian markets. Methods The study was a cross-sectional assessing the evaluation of processed clay and effects it has on the nutrition of the consumers in the political capital town of Ghana. The items for the examination was processed clay soil samples. Results Staphylococcus spp and fecal coliforms including Klebsiella, Escherichia, and Shigella and Enterobacterspp were isolated from the clay samples. Samples from the Kaneshie market in Accra recorded the highest total viable counts 6.5 Log cfu/g and Staphylococcal count 5.8 Log cfu/g. For fecal coliforms, Madina market samples had the highest count 6.5 Log cfu/g and also recorded the highest levels of yeast and mould. For Koforidua, total viable count was highest in the samples from the Zongo market 6.3 Log cfu/g. Central market samples had the highest count of fecal coliforms 4.6 Log cfu/g and yeasts and moulds 6.5 Log cfu/g. “Small” market recorded the highest staphylococcal count 6.2 Log cfu/g. The water activity of the clay samples were low, and ranged between 0.65±0.01 and 0.66±0.00 for samples collected from Koforidua and Accra respectively. Conclusion The clay samples were found to contain Klebsiella spp. Escherichia, Enterobacter, Shigella spp. staphylococcus spp., yeast and mould. These have health implications when consumed. PMID:27642456

Tips and tricks for flow cytometry-based analysis and counting of microparticles.

PubMed

Poncelet, Philippe; Robert, Stéphane; Bailly, Nicolas; Garnache-Ottou, Francine; Bouriche, Tarik; Devalet, Bérangère; Segatchian, Jerard H; Saas, Philippe; Mullier, François

2015-10-01

Submicron-sized extra-cellular vesicles generated by budding from the external cell membranes, microparticles (MPs) are important actors in transfusion as well as in other medical specialties. After briefly positioning their role in the characterization of labile blood products, this technically oriented chapter aims to review practical points that need to be considered when trying to use flow cytometry for the analysis, characterization and absolute counting of MP subsets. Subjects of active discussions relative to instrumentation will include the choice of the trigger parameter, possible standardization approaches requiring instrument quality-control, origin and control of non-specific background and of coincidence artifacts, choice of the type of electronic signals, optimal sheath fluid and sample speed. Questions related to reagents will cover target antigens and receptors, multi-color reagents, negative controls, enumeration of MPs and limiting artifacts due to unexpected (micro-) coagulation of plasma samples. Newly detected problems are generating innovative solutions and flow cytometry will continue to remain the technology of choice for the analysis of MPs, in the domain of transfusion as well as in many diverse specialties. Copyright © 2015 Elsevier Ltd. All rights reserved.

Estimating and comparing microbial diversity in the presence of sequencing errors

PubMed Central

Chiu, Chun-Huo

2016-01-01

Estimating and comparing microbial diversity are statistically challenging due to limited sampling and possible sequencing errors for low-frequency counts, producing spurious singletons. The inflated singleton count seriously affects statistical analysis and inferences about microbial diversity. Previous statistical approaches to tackle the sequencing errors generally require different parametric assumptions about the sampling model or about the functional form of frequency counts. Different parametric assumptions may lead to drastically different diversity estimates. We focus on nonparametric methods which are universally valid for all parametric assumptions and can be used to compare diversity across communities. We develop here a nonparametric estimator of the true singleton count to replace the spurious singleton count in all methods/approaches. Our estimator of the true singleton count is in terms of the frequency counts of doubletons, tripletons and quadrupletons, provided these three frequency counts are reliable. To quantify microbial alpha diversity for an individual community, we adopt the measure of Hill numbers (effective number of taxa) under a nonparametric framework. Hill numbers, parameterized by an order q that determines the measures’ emphasis on rare or common species, include taxa richness (q = 0), Shannon diversity (q = 1, the exponential of Shannon entropy), and Simpson diversity (q = 2, the inverse of Simpson index). A diversity profile which depicts the Hill number as a function of order q conveys all information contained in a taxa abundance distribution. Based on the estimated singleton count and the original non-singleton frequency counts, two statistical approaches (non-asymptotic and asymptotic) are developed to compare microbial diversity for multiple communities. (1) A non-asymptotic approach refers to the comparison of estimated diversities of standardized samples with a common finite sample size or sample completeness. This approach aims to compare diversity estimates for equally-large or equally-complete samples; it is based on the seamless rarefaction and extrapolation sampling curves of Hill numbers, specifically for q = 0, 1 and 2. (2) An asymptotic approach refers to the comparison of the estimated asymptotic diversity profiles. That is, this approach compares the estimated profiles for complete samples or samples whose size tends to be sufficiently large. It is based on statistical estimation of the true Hill number of any order q ≥ 0. In the two approaches, replacing the spurious singleton count by our estimated count, we can greatly remove the positive biases associated with diversity estimates due to spurious singletons and also make fair comparisons across microbial communities, as illustrated in our simulation results and in applying our method to analyze sequencing data from viral metagenomes. PMID:26855872

Generalized linear models and point count data: statistical considerations for the design and analysis of monitoring studies

Treesearch

Nathaniel E. Seavy; Suhel Quader; John D. Alexander; C. John Ralph

2005-01-01

The success of avian monitoring programs to effectively guide management decisions requires that studies be efficiently designed and data be properly analyzed. A complicating factor is that point count surveys often generate data with non-normal distributional properties. In this paper we review methods of dealing with deviations from normal assumptions, and we focus...

Habitat relationships of landbirds in the Northern Region, USDA Forest Service

Treesearch

Richard L. Hutto; Jock S. Young

1999-01-01

A series of first-generation habitat-relationships models for 83 bird species were detected in a 3-year study on point counts conducted in association with the USDA Forest Service's Northern Region Landbird Monitoring Program. The models depict probabilities of detection for each of the bird species on 100-m-radius, 10-minute point counts conducted across a series...

Recent stability of resident and migratory landbird populations in National Parks of the Pacific Northwest

USGS Publications Warehouse

Ray, Chris; Saracco, James; Holmgren, Mandy; Wilkerson, Robert; Siegel, Rodney; Jenkins, Kurt J.; Ransom, Jason I.; Happe, Patricia J.; Boetsch, John; Huff, Mark

2017-01-01

Monitoring species in National Parks facilitates inference regarding effects of climate change on population dynamics because parks are relatively unaffected by other forms of anthropogenic disturbance. Even at early points in a monitoring program, identifying climate covariates of population density can suggest vulnerabilities to future change. Monitoring landbird populations in parks during the breeding season brings the added benefit of allowing a comparative approach to inference across a large suite of species with diverse requirements. For example, comparing resident and migratory species that vary in exposure to non-park habitats can reveal the relative importance of park effects, such as those related to local climate. We monitored landbirds using breeding-season point-count data collected during 2005–2014 in three wilderness areas of the Pacific Northwest (Mount Rainier, North Cascades, and Olympic National Parks). For 39 species, we estimated recent trends in population density while accounting for individual detection probability using Bayesian hierarchical N-mixture models. Our analyses integrated several recent developments in N-mixture modeling, incorporating interval and distance sampling to estimate distinct components of detection probability while also accommodating count intervals of varying duration, annual variation in the length and number of point-count transects, spatial autocorrelation, random effects, and covariates of detection and density. As covariates of density, we considered metrics of precipitation and temperature hypothesized to affect breeding success. We also considered effects of park and elevational stratum on trend. Regardless of model structure, we estimated stable or increasing densities during 2005–2014 for most populations. Mean trends across species were positive for migrants in every park and for residents in one park. A recent snowfall deficit in this region might have contributed to the positive trend, because population density varied inversely with precipitation-as-snow for both migrants and residents. Densities varied directly but much more weakly with mean spring temperature. Our approach exemplifies an analytical framework for estimating trends from point-count data, and for assessing the role of climatic and other spatiotemporal variables in driving those trends. Understanding population trends and the factors that drive them is critical for adaptive management and resource stewardship in the context of climate change.

Short communication: Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count.

PubMed

Koop, G; Dik, N; Nielen, M; Lipman, L J A

2010-06-01

The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms, 3 bulk milk samples were collected at intervals of 2 wk. The samples were cultured for SPC, coliform count, and staphylococcal count and for the presence of Staphylococcus aureus. Furthermore, SCC (Fossomatic 5000, Foss, Hillerød, Denmark) and TBC (BactoScan FC 150, Foss) were measured. Staphylococcal count was correlated to SCC (r=0.40), TBC (r=0.51), and SPC (r=0.53). Coliform count was correlated to TBC (r=0.33), but not to any of the other variables. Staphylococcus aureus did not correlate to SCC. The contribution of the staphylococcal count to the SPC was 31%, whereas the coliform count comprised only 1% of the SPC. The agreement of the repeated measurements was low. This study indicates that staphylococci in goat bulk milk are related to SCC and make a significant contribution to SPC. Because of the high variation in bacterial counts, repeated sampling is necessary to draw valid conclusions from bulk milk culturing. 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A Unified Approach to Electron Counting in Main-Group Clusters

ERIC Educational Resources Information Center

McGrady, John E.

2004-01-01

A presentation of an extensive review of traditional approaches to teaching electron counting is given. The electron-precise clusters are usually taken as a reference point for rationalizing the structures of their electron-rich counterparts, which are characterized by valence electron counts greater than 5n.

Lens-free microscopy of cerebrospinal fluid for the laboratory diagnosis of meningitis

NASA Astrophysics Data System (ADS)

Delacroix, Robin; Morel, Sophie Nhu An; Hervé, Lionel; Bordy, Thomas; Blandin, Pierre; Dinten, Jean-Marc; Drancourt, Michel; Allier, Cédric

2018-02-01

The cytology of the cerebrospinal fluid is traditionally performed by an operator (physician, biologist) by means of a conventional light microscope. The operator visually counts the leukocytes (white blood cells) present in a sample of cerebrospinal fluid (10 μl). It is a tedious job and the result is operator-dependent. Here in order to circumvent the limitations of manual counting, we approach the question of numeration of erythrocytes and leukocytes for the cytological diagnosis of meningitis by means of lens-free microscopy. In a first step, a prospective counts of leukocytes was performed by five different operators using conventional optical microscopy. The visual counting yielded an overall 16.7% misclassification of 72 cerebrospinal fluid specimens in meningitis/non-meningitis categories using a 10 leukocyte/μL cut-off. In a second step, the lens-free microscopy algorithm was adapted step-by-step for counting cerebrospinal fluid cells and discriminating leukocytes from erythrocytes. The optimization of the automatic lens-free counting was based on the prospective analysis of 215 cerebrospinal fluid specimens. The optimized algorithm yielded a 100% sensitivity and a 86% specificity compared to confirmed diagnostics. In a third step, a blind lens-free microscopic analysis of 116 cerebrospinal fluid specimens, including six cases of microbiology confirmed infectious meningitis, yielded a 100% sensitivity and a 79% specificity. Adapted lens-free microscopy is thus emerging as an operator-independent technique for the rapid numeration of leukocytes and erythrocytes in cerebrospinal fluid. In particular, this technique is well suited to the rapid diagnosis of meningitis at point-of-care laboratories.

Assessment of the application of an automated electronic milk analyzer for the enumeration of total bacteria in raw goat milk.

PubMed

Ramsahoi, L; Gao, A; Fabri, M; Odumeru, J A

2011-07-01

Automated electronic milk analyzers for rapid enumeration of total bacteria counts (TBC) are widely used for raw milk testing by many analytical laboratories worldwide. In Ontario, Canada, Bactoscan flow cytometry (BsnFC; Foss Electric, Hillerød, Denmark) is the official anchor method for TBC in raw cow milk. Penalties are levied at the BsnFC equivalent level of 50,000 cfu/mL, the standard plate count (SPC) regulatory limit. This study was conducted to assess the BsnFC for TBC in raw goat milk, to determine the mathematical relationship between the SPC and BsnFC methods, and to identify probable reasons for the difference in the SPC:BsnFC equivalents for goat and cow milks. Test procedures were conducted according to International Dairy Federation Bulletin guidelines. Approximately 115 farm bulk tank milk samples per month were tested for inhibitor residues, SPC, BsnFC, psychrotrophic bacteria count, composition (fat, protein, lactose, lactose and other solids, and freezing point), and somatic cell count from March 2009 to February 2010. Data analysis of the results for the samples tested indicated that the BsnFC method would be a good alternative to the SPC method, providing accurate and more precise results with a faster turnaround time. Although a linear regression model showed good correlation and prediction, tests for linearity indicated that the relationship was linear only beyond log 4.1 SPC. The logistic growth curve best modeled the relationship between the SPC and BsnFC for the entire sample population. The BsnFC equivalent to the SPC 50,000 cfu/mL regulatory limit was estimated to be 321,000 individual bacteria count (ibc)/mL. This estimate differs considerably from the BsnFC equivalent for cow milk (121,000 ibc/mL). Because of the low frequency of bulk tank milk pickups at goat farms, 78.5% of the samples had their oldest milking in the tank to be 6.5 to 9.0 d old when tested, compared with the cow milk samples, which had their oldest milking at 4 d old when tested. This may be one of the major factors contributing to the larger goat milk BsnFC equivalence. Correlations and interactions between various test results were also discussed to further understand differences between the 2 methods for goat and cow milks. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Automated cell counts on CSF samples: A multicenter performance evaluation of the GloCyte system.

PubMed

Hod, E A; Brugnara, C; Pilichowska, M; Sandhaus, L M; Luu, H S; Forest, S K; Netterwald, J C; Reynafarje, G M; Kratz, A

2018-02-01

Automated cell counters have replaced manual enumeration of cells in blood and most body fluids. However, due to the unreliability of automated methods at very low cell counts, most laboratories continue to perform labor-intensive manual counts on many or all cerebrospinal fluid (CSF) samples. This multicenter clinical trial investigated if the GloCyte System (Advanced Instruments, Norwood, MA), a recently FDA-approved automated cell counter, which concentrates and enumerates red blood cells (RBCs) and total nucleated cells (TNCs), is sufficiently accurate and precise at very low cell counts to replace all manual CSF counts. The GloCyte System concentrates CSF and stains RBCs with fluorochrome-labeled antibodies and TNCs with nucleic acid dyes. RBCs and TNCs are then counted by digital image analysis. Residual adult and pediatric CSF samples obtained for clinical analysis at five different medical centers were used for the study. Cell counts were performed by the manual hemocytometer method and with the GloCyte System following the same protocol at all sites. The limits of the blank, detection, and quantitation, as well as precision and accuracy of the GloCyte, were determined. The GloCyte detected as few as 1 TNC/μL and 1 RBC/μL, and reliably counted as low as 3 TNCs/μL and 2 RBCs/μL. The total coefficient of variation was less than 20%. Comparison with cell counts obtained with a hemocytometer showed good correlation (>97%) between the GloCyte and the hemocytometer, including at very low cell counts. The GloCyte instrument is a precise, accurate, and stable system to obtain red cell and nucleated cell counts in CSF samples. It allows for the automated enumeration of even very low cell numbers, which is crucial for CSF analysis. These results suggest that GloCyte is an acceptable alternative to the manual method for all CSF samples, including those with normal cell counts. © 2017 John Wiley & Sons Ltd.

Prevalence of bacteria and absence of anisakid parasites in raw and prepared fish and seafood dishes in Spanish restaurants.

PubMed

Sospedra, I; Rubert, J; Soriano, J M; Mañes, J; Fuentes, M V

2015-03-01

This study evaluated the presence of bacteria and anisakid parasites in 45 samples of raw anchovies in vinegar, a dish widely eaten in Spain, and in 227 samples of cooked fish and cephalopods served in Spanish food service establishments. Our analysis showed that, according to European and Spanish regulation, 14 to 30% of the prepared fish and cephalopod dishes exceeded the maximum allowable level for mesophilic aerobic counts, and 10 to 40% of these samples exceeded the allowable levels for Enterobacteriaceae. None of the studied samples showed evidence of anisakid parasites, Escherichia coli, Staphylococcus aureus, Salmonella, or Listeria monocytogenes. These results indicate that application of hazard analysis and critical control points, food safety training courses, and routine inspections in compliance with current European and Spanish legislation help protect consumer health.

An Adaptation of the Distance Driven Projection Method for Single Pinhole Collimators in SPECT Imaging

NASA Astrophysics Data System (ADS)

Ihsani, Alvin; Farncombe, Troy

2016-02-01

The modelling of the projection operator in tomographic imaging is of critical importance especially when working with algebraic methods of image reconstruction. This paper proposes a distance-driven projection method which is targeted to single-pinhole single-photon emission computed tomograghy (SPECT) imaging since it accounts for the finite size of the pinhole, and the possible tilting of the detector surface in addition to other collimator-specific factors such as geometric sensitivity. The accuracy and execution time of the proposed method is evaluated by comparing to a ray-driven approach where the pinhole is sub-sampled with various sampling schemes. A point-source phantom whose projections were generated using OpenGATE was first used to compare the resolution of reconstructed images with each method using the full width at half maximum (FWHM). Furthermore, a high-activity Mini Deluxe Phantom (Data Spectrum Corp., Durham, NC, USA) SPECT resolution phantom was scanned using a Gamma Medica X-SPECT system and the signal-to-noise ratio (SNR) and structural similarity of reconstructed images was compared at various projection counts. Based on the reconstructed point-source phantom, the proposed distance-driven approach results in a lower FWHM than the ray-driven approach even when using a smaller detector resolution. Furthermore, based on the Mini Deluxe Phantom, it is shown that the distance-driven approach has consistently higher SNR and structural similarity compared to the ray-driven approach as the counts in measured projections deteriorates.

Distribution and prevalence of airborne microorganisms in three commercial poultry processing plants.

PubMed

Whyte, P; Collins, J D; McGill, K; Monahan, C; O'Mahony, H

2001-03-01

Airborne microbial contaminants and indicator organisms were monitored within three poultry processing plants (plants A, B, and C). In total, 15 cubic feet (c.f.) of air was sampled per location during 15 visits to each plant and quantitatively analyzed for total mesophilic and psychrophilic aerobic counts, thermophilic campylobacters, Escherichia coli, and Enterobacteriaceae. The prevalence of Salmonella spp. in air samples was also evaluated. Significant reductions in total aerobic counts were observed between defeathering and evisceration areas of the three plants (P < 0.05). Mesophilic plate counts were highest in the defeathering areas of all plants compared to equivalent psychrophilic plate counts. Enterobacteriaceae counts were highest in the defeathering areas of all three plants with counts of log10 1.63, 1.53, and 1.18 CFU/15 c.f. recovered in plants A, B, and C, respectively. E. coli enumerated from air samples in the defeathering areas exhibited a similar trend to those obtained for Enterobacteriaceae with log10 1.67, 1.58, and 1.18 CFU for plants A, B, and C, respectively. Thermophilic campylobacters were most frequently isolated from samples in the defeathering areas followed by the evisceration areas. The highest mean counts of the organism were observed in plant A at 21 CFU/15 c.f. sample with plants B and C at 9 and 8 CFU/sample, respectively. With the exception of low levels of Enterobacteriaceae recovered from samples in the on-line air chill in plant A, E. coli, Enterobacteriaceae, or Campylobacter spp. were not isolated from samples in postevisceration sites in any of the plants examined. Salmonella spp. were not recovered from any samples during the course of the investigation.

Non-destructive lichen biomass estimation in northwestern Alaska: a comparison of methods.

PubMed

Rosso, Abbey; Neitlich, Peter; Smith, Robert J

2014-01-01

Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa "community" samples, n = 144) at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count), among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume) as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4%) using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m-2). Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community) approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska.

Non-Destructive Lichen Biomass Estimation in Northwestern Alaska: A Comparison of Methods

PubMed Central

Rosso, Abbey; Neitlich, Peter; Smith, Robert J.

2014-01-01

Terrestrial lichen biomass is an important indicator of forage availability for caribou in northern regions, and can indicate vegetation shifts due to climate change, air pollution or changes in vascular plant community structure. Techniques for estimating lichen biomass have traditionally required destructive harvesting that is painstaking and impractical, so we developed models to estimate biomass from relatively simple cover and height measurements. We measured cover and height of forage lichens (including single-taxon and multi-taxa “community” samples, n = 144) at 73 sites on the Seward Peninsula of northwestern Alaska, and harvested lichen biomass from the same plots. We assessed biomass-to-volume relationships using zero-intercept regressions, and compared differences among two non-destructive cover estimation methods (ocular vs. point count), among four landcover types in two ecoregions, and among single-taxon vs. multi-taxa samples. Additionally, we explored the feasibility of using lichen height (instead of volume) as a predictor of stand-level biomass. Although lichen taxa exhibited unique biomass and bulk density responses that varied significantly by growth form, we found that single-taxon sampling consistently under-estimated true biomass and was constrained by the need for taxonomic experts. We also found that the point count method provided little to no improvement over ocular methods, despite increased effort. Estimated biomass of lichen-dominated communities (mean lichen cover: 84.9±1.4%) using multi-taxa, ocular methods differed only nominally among landcover types within ecoregions (range: 822 to 1418 g m−2). Height alone was a poor predictor of lichen biomass and should always be weighted by cover abundance. We conclude that the multi-taxa (whole-community) approach, when paired with ocular estimates, is the most reasonable and practical method for estimating lichen biomass at landscape scales in northwest Alaska. PMID:25079228

New method for estimating bacterial cell abundances in natural samples by use of sublimation

NASA Technical Reports Server (NTRS)

Glavin, Daniel P.; Cleaves, H. James; Schubert, Michael; Aubrey, Andrew; Bada, Jeffrey L.

2004-01-01

We have developed a new method based on the sublimation of adenine from Escherichia coli to estimate bacterial cell counts in natural samples. To demonstrate this technique, several types of natural samples, including beach sand, seawater, deep-sea sediment, and two soil samples from the Atacama Desert, were heated to a temperature of 500 degrees C for several seconds under reduced pressure. The sublimate was collected on a cold finger, and the amount of adenine released from the samples was then determined by high-performance liquid chromatography with UV absorbance detection. Based on the total amount of adenine recovered from DNA and RNA in these samples, we estimated bacterial cell counts ranging from approximately 10(5) to 10(9) E. coli cell equivalents per gram. For most of these samples, the sublimation-based cell counts were in agreement with total bacterial counts obtained by traditional DAPI (4,6-diamidino-2-phenylindole) staining.

Using a Mobile Device "App" and Proximal Remote Sensing Technologies to Assess Soil Cover Fractions on Agricultural Fields.

PubMed

Laamrani, Ahmed; Pardo Lara, Renato; Berg, Aaron A; Branson, Dave; Joosse, Pamela

2018-02-27

Quantifying the amount of crop residue left in the field after harvest is a key issue for sustainability. Conventional assessment approaches (e.g., line-transect) are labor intensive, time-consuming and costly. Many proximal remote sensing devices and systems have been developed for agricultural applications such as cover crop and residue mapping. For instance, current mobile devices (smartphones & tablets) are usually equipped with digital cameras and global positioning systems and use applications (apps) for in-field data collection and analysis. In this study, we assess the feasibility and strength of a mobile device app developed to estimate crop residue cover. The performance of this novel technique (from here on referred to as "app" method) was compared against two point counting approaches: an established digital photograph-grid method and a new automated residue counting script developed in MATLAB at the University of Guelph. Both photograph-grid and script methods were used to count residue under 100 grid points. Residue percent cover was estimated using the app, script and photograph-grid methods on 54 vertical digital photographs (images of the ground taken from above at a height of 1.5 m) collected from eighteen fields (9 corn and 9 soybean, 3 samples each) located in southern Ontario. Results showed that residue estimates from the app method were in good agreement with those obtained from both photograph-grid and script methods (R² = 0.86 and 0.84, respectively). This study has found that the app underestimates the residue coverage by -6.3% and -10.8% when compared to the photograph-grid and script methods, respectively. With regards to residue type, soybean has a slightly lower bias than corn (i.e., -5.3% vs. -7.4%). For photos with residue <30%, the app derived residue measurements are within ±5% difference (bias) of both photograph-grid- and script-derived residue measurements. These methods could therefore be used to track the recommended minimum soil residue cover of 30%, implemented to reduce farmland topsoil and nutrient losses that impact water quality. Overall, the app method was found to be a good alternative to the point counting methods, which are more time-consuming.

Microbiological standards and handling codes for chilled and frozen foods. A review.

PubMed

ELLIOTT, R P; MICHENER, H D

1961-09-01

The usefulness of microbiological standards for frozen foods is now a controversy in the trade and scientific literature. Most reviewers have given arguments both for and against, and have concluded that they should be applied with great caution. Such standards have the advantage of putting questions of safety on a convenient numerical basis. Canadian workers have reported that promulgation of standards has invariably raised the hygienic level of the products controlled. Bacteriological standards have often been associated with the question of safety to the consumer. Everyone recognizes that food poisoning bacteria are a potential danger in any food. But many have argued that the history of food poisoning outbreaks from frozen foods is excellent and that there is no need for standards; on the other hand, proponents of standards have pointed to the incomplete investigation and reporting of outbreaks, and have argued that there may be more outbreaks than we realize. They have pointed to laboratory studies that have shown grossly mishandled precooked frozen foods to be truly dangerous. Some have proposed that pathogens should be absent from foods; but others have questioned that a microbiological standard can accomplish this end. Some pathogens, such as Salmonella or Staphylococcus have been shown to be so ubiquitous that their presence in some commercial foods is unavoidable. Also, sampling and analytical methods have been described as inadequate to guarantee that pathogens present will be detected. Some have argued that control at the source is a better way-through inspections of the plant operation, by enforcement of handling codes, or by processing procedures such as pasteurization, which would be more certain to result in a pathogen-free food.A most important part of any of the proposed standards is a "total count" of viable aerobic bacteria. English workers have found that foods causing poisoning outbreaks usually had total viable counts above 10 million per gram. On the other hand, these same workers found Salmonella on meats with very low total viable count. The assumption by many that low total count indicates safety has been shown to be not always true. Furthermore, high counts of nonpathogenic organisms, such as psychrophilic saprophytes would have no public health significance. The relation between bacterial level and quality is open to less controversy. Some authorities have pointed to bacterial level as a measure of sanitation, adequacy of refrigeration, or speed of handling. Others have indicated that to determine which of these factors caused a high count would be impossible with only a total count on the product as a guide. Some investigators have said a high count affects flavor adversely before actual spoilage is evident, and this may be a factor in competition on today's market. It is well established that initial bacterial level will affect the shelf-life of a chilled product. Methods of analysis are more nearly adequate for counts than for pathogens, but they need improvement, and should be clearly specified as part of any bacteriological standard. Foods with high count could sometimes be brought into compliance merely by storing them for a sufficient period frozen, or by heating them slightly. This has been cited by some authors as a disadvantage of bacteriological standards. The enterococci and the coliform group (except Escherichia coli) have been shown to be ubiquitous and therefore should not be used alone to indicate fecal contamination. Although E. coli has greater significance, its source should be determined each time it is found. Various reviewers have expressed the need for caution in the application of standards. The principal precautionary arguments we have found are as follows:1) A single set of microbiological standards should not be applied to foods as a miscellaneous group, such as "frozen foods" or "precooked foods."2) Microbiological standards should be applied first to the more hazardous types of foods on an individual basis, after sufficient data are accumulated on expected bacterial levels, with consideration of variations in composition, processing procedures, and time of frozen storage.3) When standards are chosen, there should be a definite relation between the standard and the hazard against which it is meant to protect the public.4) Methods of sampling and analysis should be carefully studied for reliability and reproducibility among laboratories, and chosen methods should be specified in detail as part of the standard.5) Tolerances should be included in the standard to account for inaccuracies of sampling and analysis.6) At first, the standard should be applied on a tentative basis to allow for voluntary compliance before becoming a strictly enforced regulation.7) Microbiological standards will be expensive to enforce.8) If standards are unwisely chosen they will not stand in courts of law.

Counting conformal correlators

NASA Astrophysics Data System (ADS)

Kravchuk, Petr; Simmons-Duffin, David

2018-02-01

We introduce simple group-theoretic techniques for classifying conformallyinvariant tensor structures. With them, we classify tensor structures of general n-point functions of non-conserved operators, and n ≥ 4-point functions of general conserved currents, with or without permutation symmetries, and in any spacetime dimension d. Our techniques are useful for bootstrap applications. The rules we derive simultaneously count tensor structures for flat-space scattering amplitudes in d + 1 dimensions.

Stereological evaluation of the volume and volume fraction of newborns' brain compartment and brain in magnetic resonance images.

PubMed

Nisari, Mehtap; Ertekin, Tolga; Ozçelik, Ozlem; Cınar, Serife; Doğanay, Selim; Acer, Niyazi

2012-11-01

Brain development in early life is thought to be critical period in neurodevelopmental disorder. Knowledge relating to this period is currently quite limited. This study aimed to evaluate the volume relation of total brain (TB), cerebrum, cerebellum and bulbus+pons by the use of Archimedes' principle and stereological (point-counting) method and after that to compare these approaches with each other in newborns. This study was carried out on five newborn cadavers mean weighing 2.220 ± 1.056 g with no signs of neuropathology. The mean (±SD) age of the subjects was 39.7 (±1.5) weeks. The volume and volume fraction of the total brain, cerebrum, cerebellum and bulbus+pons were determined on magnetic resonance (MR) images using the point-counting approach of stereological methods and by the use of fluid displacement technique. The mean (±SD) TB, cerebrum, cerebellum and bulbus+pons volumes by fluid displacement were 271.48 ± 78.3, 256.6 ± 71.8, 12.16 ± 6.1 and 2.72 ± 1.6 cm3, respectively. By the Cavalieri principle (point-counting) using sagittal MRIs, they were 262.01 ± 74.9, 248.11 ± 68.03, 11.68 ± 6.1 and 2.21 ± 1.13 cm3, respectively. The mean (± SD) volumes by point-counting technique using axial MR images were 288.06 ± 88.5, 275.2 ± 83.1, 19.75 ± 5.3 and 2.11 ± 0.7 cm3, respectively. There were no differences between the fluid displacement and point-counting (using axial and sagittal images) for all structures (p > 0.05). This study presents the basic data for studies relative to newborn's brain volume fractions according to two methods. Stereological (point-counting) estimation may be accepted a beneficial and new tool for neurological evaluation in vivo research of the brain. Based on these techniques we introduce here, the clinician may evaluate the growth of the brain in a more efficient and precise manner.

UAS-based automatic bird count of a common gull colony

NASA Astrophysics Data System (ADS)

Grenzdörffer, G. J.

2013-08-01

The standard procedure to count birds is a manual one. However a manual bird count is a time consuming and cumbersome process, requiring several people going from nest to nest counting the birds and the clutches. High resolution imagery, generated with a UAS (Unmanned Aircraft System) offer an interesting alternative. Experiences and results of UAS surveys for automatic bird count of the last two years are presented for the bird reserve island Langenwerder. For 2011 1568 birds (± 5%) were detected on the image mosaic, based on multispectral image classification and GIS-based post processing. Based on the experiences of 2011 the results and the accuracy of the automatic bird count 2012 became more efficient. For 2012 1938 birds with an accuracy of approx. ± 3% were counted. Additionally a separation of breeding and non-breeding birds was performed with the assumption, that standing birds cause a visible shade. The final section of the paper is devoted to the analysis of the 3D-point cloud. Thereby the point cloud was used to determine the height of the vegetation and the extend and depth of closed sinks, which are unsuitable for breeding birds.

Digital encoding of cellular mRNAs enabling precise and absolute gene expression measurement by single-molecule counting.

PubMed

Fu, Glenn K; Wilhelmy, Julie; Stern, David; Fan, H Christina; Fodor, Stephen P A

2014-03-18

We present a new approach for the sensitive detection and accurate quantitation of messenger ribonucleic acid (mRNA) gene transcripts in single cells. First, the entire population of mRNAs is encoded with molecular barcodes during reverse transcription. After amplification of the gene targets of interest, molecular barcodes are counted by sequencing or scored on a simple hybridization detector to reveal the number of molecules in the starting sample. Since absolute quantities are measured, calibration to standards is unnecessary, and many of the relative quantitation challenges such as polymerase chain reaction (PCR) bias are avoided. We apply the method to gene expression analysis of minute sample quantities and demonstrate precise measurements with sensitivity down to sub single-cell levels. The method is an easy, single-tube, end point assay utilizing standard thermal cyclers and PCR reagents. Accurate and precise measurements are obtained without any need for cycle-to-cycle intensity-based real-time monitoring or physical partitioning into multiple reactions (e.g., digital PCR). Further, since all mRNA molecules are encoded with molecular barcodes, amplification can be used to generate more material for multiple measurements and technical replicates can be carried out on limited samples. The method is particularly useful for small sample quantities, such as single-cell experiments. Digital encoding of cellular content preserves true abundance levels and overcomes distortions introduced by amplification.

Effects of ionizing energy treatment on the quality of ginseng products

NASA Astrophysics Data System (ADS)

Kwon, Joong-Ho; Bélanger, Jacqueline M. R.; Paré, J. R. Jocelyn

Pre-established doses were applied to Panax ginseng powders for determining the effects of γ-irradiation on the quality of samples from the microbiological, some physico-chemical and organoleptic points of view. Irradiation at 5 kGy was sufficient not only to reduce total bacterial counts (1.28 × 10 5/g) by about 3 orders of magnitude but to eliminate coliforms, yeast and molds during three months of storage at 30°C and 50-60% RH. An established dose of 5 kGy caused little change in pH, acidity, TBA number, pigments, color, and overall acceptability of the sample, however there was a significant change in color and appearance of the irradiated sample at 10 kGy where all microorganisms were destroyed.

Clustering method for counting passengers getting in a bus with single camera

NASA Astrophysics Data System (ADS)

Yang, Tao; Zhang, Yanning; Shao, Dapei; Li, Ying

2010-03-01

Automatic counting of passengers is very important for both business and security applications. We present a single-camera-based vision system that is able to count passengers in a highly crowded situation at the entrance of a traffic bus. The unique characteristics of the proposed system include, First, a novel feature-point-tracking- and online clustering-based passenger counting framework, which performs much better than those of background-modeling-and foreground-blob-tracking-based methods. Second, a simple and highly accurate clustering algorithm is developed that projects the high-dimensional feature point trajectories into a 2-D feature space by their appearance and disappearance times and counts the number of people through online clustering. Finally, all test video sequences in the experiment are captured from a real traffic bus in Shanghai, China. The results show that the system can process two 320×240 video sequences at a frame rate of 25 fps simultaneously, and can count passengers reliably in various difficult scenarios with complex interaction and occlusion among people. The method achieves high accuracy rates up to 96.5%.

33 CFR 159.127 - Safety coliform count: Recirculating devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety coliform count....127 Safety coliform count: Recirculating devices. Thirty-eight of forty samples of flush fluid from a recirculating device must have less than 240 fecal coliform bacteria per 100 milliliters. These samples must be...

N-point correlation functions in the CfA and SSRS redshift distribution of galaxies

NASA Technical Reports Server (NTRS)

Gaztanaga, Enrique

1992-01-01

Using counts in cells, we estimate the volume-average N-point galaxy correlation functions for N = 2, 3, and 4, in redshift samples of the CfA and SSRS catalogs. Volume-limited samples of different sizes are used to study the uncertainties at different scales, the shot noise, and the problem with the boundaries. The hierarchical constants S3 and S4 agree well in all samples in CfA and SSRS, with average S3 = 194 +/- 0.07 and S4 = 4.56 +/- 0.53. We compare these results with estimates obtained from angular catalogs and recent analysis over IRAS samples. The amplitudes SJ seem larger in real space than in redshift space, although the values from the angular analysis correspond to smaller scales, where we might expect larger nonperturbative effects. It is also found that S3 and S4 are smaller for IRAS than for optical galaxies. This, together with the fact that IRAS galaxies have smaller amplitude for the above correlation functions, indicates that the density fluctuations of IRAS galaxies cannot be simply proportional to the density fluctuations of optical galaxies, i.e., biasing has to be nonlinear between them.

A Microbial Assessment Scheme to measure microbial performance of Food Safety Management Systems.

PubMed

Jacxsens, L; Kussaga, J; Luning, P A; Van der Spiegel, M; Devlieghere, F; Uyttendaele, M

2009-08-31

A Food Safety Management System (FSMS) implemented in a food processing industry is based on Good Hygienic Practices (GHP), Hazard Analysis Critical Control Point (HACCP) principles and should address both food safety control and assurance activities in order to guarantee food safety. One of the most emerging challenges is to assess the performance of a present FSMS. The objective of this work is to explain the development of a Microbial Assessment Scheme (MAS) as a tool for a systematic analysis of microbial counts in order to assess the current microbial performance of an implemented FSMS. It is assumed that low numbers of microorganisms and small variations in microbial counts indicate an effective FSMS. The MAS is a procedure that defines the identification of critical sampling locations, the selection of microbiological parameters, the assessment of sampling frequency, the selection of sampling method and method of analysis, and finally data processing and interpretation. Based on the MAS assessment, microbial safety level profiles can be derived, indicating which microorganisms and to what extent they contribute to food safety for a specific food processing company. The MAS concept is illustrated with a case study in the pork processing industry, where ready-to-eat meat products are produced (cured, cooked ham and cured, dried bacon).

[Comparison of three histometric methods for the comprehension of stimulating effects on the rat thyroid gland].

PubMed

Herrmann, F; Hambsch, K; Wolf, T; Rother, P; Müller, P

1989-01-01

There exist some histometric methods for the morphological quantification of different strongly stimulating effects on the thyroid gland induced by drugs and/or other chemical substances in dependence upon dose and duration of application. But in respect of technical and temporal expense and also diagnostic statement, there are considerable differences between these recording procedures. Therefore we examined the 3 mostly used methods synchronously (i.e. determination of thyroid epithelial cell height, nuclear volume in thyrocytes, and estimation of relative volume parts in the thyroid gland by the point counting method) by investigating the thyroid glands of methylthiouracil-(MTU)-stimulated rats and corresponding controls in order to compare the diagnostic value and temporal expense. The largest temporal expense was required in the nuclear volume determination, the smallest in the point-counting method. On principle, all 3 procedures allow the determination of hypertrophic alterations but only by help of the point-counting method, also hyperplastic changes are recognizable. By nuclear volume determination, we found significant differences between central and peripheral parts of the thyroid gland. Therefore, to avoid the subjective error, it will be necessary to measure a large number of nuclei in many planes of the gland. Also the determination of epithelial cell high reinforces the subjective error because of the heterological structure especially in unstimulated thyroid gland. If the number of counting points is exactly determined and, full of sense, limited, the point-counting method allows a nearly complete measuring of the whole object to be tested within an acceptable investigation time. In this way, the heterological structure of thyroid gland will be regarded, and comparability and reproducibility are guaranteed on an high level.

White blood cell counting system

NASA Technical Reports Server (NTRS)

1972-01-01

The design, fabrication, and tests of a prototype white blood cell counting system for use in the Skylab IMSS are presented. The counting system consists of a sample collection subsystem, sample dilution and fluid containment subsystem, and a cell counter. Preliminary test results show the sample collection and the dilution subsystems are functional and fulfill design goals. Results for the fluid containment subsystem show the handling bags cause counting errors due to: (1) adsorption of cells to the walls of the container, and (2) inadequate cleaning of the plastic bag material before fabrication. It was recommended that another bag material be selected.

Evaluation of seven aquatic sampling methods for amphibians and other aquatic fauna

USGS Publications Warehouse

Gunzburger, M.S.

2007-01-01

To design effective and efficient research and monitoring programs researchers must have a thorough understanding of the capabilities and limitations of their sampling methods. Few direct comparative studies exist for aquatic sampling methods for amphibians. The objective of this study was to simultaneously employ seven aquatic sampling methods in 10 wetlands to compare amphibian species richness and number of individuals detected with each method. Four sampling methods allowed counts of individuals (metal dipnet, D-frame dipnet, box trap, crayfish trap), whereas the other three methods allowed detection of species (visual encounter, aural, and froglogger). Amphibian species richness was greatest with froglogger, box trap, and aural samples. For anuran species, the sampling methods by which each life stage was detected was related to relative length of larval and breeding periods and tadpole size. Detection probability of amphibians varied across sampling methods. Box trap sampling resulted in the most precise amphibian count, but the precision of all four count-based methods was low (coefficient of variation > 145 for all methods). The efficacy of the four count sampling methods at sampling fish and aquatic invertebrates was also analyzed because these predatory taxa are known to be important predictors of amphibian habitat distribution. Species richness and counts were similar for fish with the four methods, whereas invertebrate species richness and counts were greatest in box traps. An effective wetland amphibian monitoring program in the southeastern United States should include multiple sampling methods to obtain the most accurate assessment of species community composition at each site. The combined use of frogloggers, crayfish traps, and dipnets may be the most efficient and effective amphibian monitoring protocol. ?? 2007 Brill Academic Publishers.

Effective estimation of correct platelet counts in pseudothrombocytopenia using an alternative anticoagulant based on magnesium salt

PubMed Central

Schuff-Werner, Peter; Steiner, Michael; Fenger, Sebastian; Gross, Hans-Jürgen; Bierlich, Alexa; Dreissiger, Katrin; Mannuß, Steffen; Siegert, Gabriele; Bachem, Maximilian; Kohlschein, Peter

2013-01-01

Pseudothrombocytopenia remains a challenge in the haematological laboratory. The pre-analytical problem that platelets tend to easily aggregate in vitro, giving rise to lower platelet counts, has been known since ethylenediamine-tetra acetic acid EDTA and automated platelet counting procedures were introduced in the haematological laboratory. Different approaches to avoid the time and temperature dependent in vitro aggregation of platelets in the presence of EDTA were tested, but none of them proved optimal for routine purposes. Patients with unexpectedly low platelet counts or flagged for suspected aggregates, were selected and smears were examined for platelet aggregates. In these cases patients were asked to consent to the drawing of an additional sample of blood anti-coagulated with a magnesium additive. Magnesium was used in the beginning of the last century as anticoagulant for microscopic platelet counts. Using this approach, we documented 44 patients with pseudothrombocytopenia. In all cases, platelet counts were markedly higher in samples anti-coagulated with the magnesium containing anticoagulant when compared to EDTA-anticoagulated blood samples. We conclude that in patients with known or suspected pseudothrombocytopenia the magnesium-anticoagulant blood samples may be recommended for platelet counting. PMID:23808903

A comparison of legionella and other bacteria concentrations in cooling tower water

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

Cappabianca, R.M.; Jurinski, N.B.; Jurinski, J.B.

1994-05-01

A field study was conducted in which water samples collected from air conditioning cooling water reservoirs of high-rise buildings throughout an urban area were assayed for Legionella and for total bacteria. Buildings included within the study had ongoing biocidal treatment programs for the cooling towers. Separate sample analyses were performed to measure the viable colony concentrations of total bacteria and of Legionella in the process waters. The occurrence and viable counts of Legionella in 304 environmental water samples were determined by inoculating them onto plates of buffered charcoal yeast extract (BCYE) agar medium (a presumptive screening method). The samples weremore » collected during summer months between July and September. BCYE plate cultures of 50 (16.4%) of the samples yielded Legionella with viable counts ranging from 2 to 608 colony forming units per milliliter. In the water samples, 281 (92.4%) yielded viable counts of bacteria that ranged from 9 to 1.2 x 10{sup 6} per milliliter. This study demonstrates that Legionella are commonly present in the water of air conditioning cooling towers and that there is no significant correlation between concurrently sampled culture plate counts of Legionella and total bacteria plate counts. Correspondingly, there is no demonstrated validity for use of total bacterial counts as an inferential surrogate for the concentration of Legionella in the water. 19 refs., 3 figs., 1 tab.« less

Brain processes in women and men in response to emotive sounds.

PubMed

Rigo, Paola; De Pisapia, Nicola; Bornstein, Marc H; Putnick, Diane L; Serra, Mauro; Esposito, Gianluca; Venuti, Paola

2017-04-01

Adult appropriate responding to salient infant signals is vital to child healthy psychological development. Here we investigated how infant crying, relative to other emotive sounds of infant laughing or adult crying, captures adults' brain resources. In a sample of nulliparous women and men, we investigated the effects of different sounds on cerebral activation of the default mode network (DMN) and reaction times (RTs) while listeners engaged in self-referential decision and syllabic counting tasks, which, respectively, require the activation or deactivation of the DMN. Sounds affect women and men differently. In women, infant crying deactivated the DMN during the self-referential decision task; in men, female adult crying interfered with the DMN during the syllabic counting task. These findings point to different brain processes underlying responsiveness to crying in women and men and show that cerebral activation is modulated by situational contexts in which crying occurs.

Demographic and Clinical Characteristics of COPD Patients at Different Blood Eosinophil Levels in the UK Clinical Practice Research Datalink.

PubMed

Landis, Sarah; Suruki, Robert; Maskell, Joe; Bonar, Kerina; Hilton, Emma; Compton, Chris

2018-03-20

Blood eosinophil count may be a useful biomarker for predicting response to inhaled corticosteroids and exacerbation risk in chronic obstructive pulmonary disease (COPD) patients. The optimal cut point for categorizing blood eosinophil counts in these contexts remains unclear. We aimed to determine the distribution of blood eosinophil count in COPD patients and matched non-COPD controls, and to describe demographic and clinical characteristics at different cut points. We identified COPD patients within the UK Clinical Practice Research Database aged ≥40 years with a FEV 1 /FVC <0.7, and ≥1 blood eosinophil count recorded during stable disease between January 1, 2010 and December 31, 2012. COPD patients were matched on age, sex, and smoking status to non-COPD controls. Using all blood eosinophil counts recorded during a 12-month period, COPD patients were categorized as "always above," "fluctuating above and below," and "never above" cut points of 100, 150, and 300 cells/μL. The geometric mean blood eosinophil count was statistically significantly higher in COPD patients versus matched controls (196.6 cells/µL vs. 182.1 cells/µL; mean difference 8%, 95% CI: 6.8, 9.2), and in COPD patients with versus without a history of asthma (205.0 cells/µL vs. 192.2 cells/µL; mean difference 6.7%, 95%, CI: 4.9, 8.5). About half of COPD patients had all blood eosinophil counts above 150 cells/μL; this persistent higher eosinophil phenotype was associated with being male, higher body mass index, and history of asthma. In conclusion, COPD patients demonstrated higher blood eosinophil count than non-COPD controls, although there was substantial overlap in the distributions. COPD patients with a history of asthma had significantly higher blood eosinophil count versus those without.

The effect of trigger point management by positional release therapy on tension type headache.

PubMed

Ghanbari, Ali; Rahimijaberi, Abbas; Mohamadi, Marzieh; Abbasi, Leila; Sarvestani, Fahimeh Kamali

2012-01-01

The aim of this study was to compare the effectiveness of trigger points' management by Positional Release Therapy (PRT) and routine medical therapy in treatment of Tension Type Headache. Tension Type Headache is the most frequent headache with the basis of myofascial and trigger point disorders. PRT is an indirect technique that treats trigger points. 30 Patients with active trigger points in cervical muscles entered to the study. They were randomly assigned to PRT or medical therapy group. Headache frequency, intensity and duration and tablet count were recorded by use of a daily headache diary. Sensitivity of trigger points was assessed by numeric pain intensity and by use of a digital force gauge (FG 5020). Both groups showed significant reduction in headache frequency and duration and tablet count after treatment phase. However, the reduction of study variables was persisted only in PRT group after follow up phase. There was no significant reduction in headache intensity, neither in PRT and nor in medication group. Sensitivity of trigger points was significantly reduced. In comparison of the two study groups, there was no significant difference in headache frequency, intensity, duration and tablet count (p> 0.05). Both procedures were equally effective according to the study. Thus, PRT can be a treatment choice for patients with T.T.H.

Hierarchical species distribution models

USGS Publications Warehouse

Hefley, Trevor J.; Hooten, Mevin B.

2016-01-01

Determining the distribution pattern of a species is important to increase scientific knowledge, inform management decisions, and conserve biodiversity. To infer spatial and temporal patterns, species distribution models have been developed for use with many sampling designs and types of data. Recently, it has been shown that count, presence-absence, and presence-only data can be conceptualized as arising from a point process distribution. Therefore, it is important to understand properties of the point process distribution. We examine how the hierarchical species distribution modeling framework has been used to incorporate a wide array of regression and theory-based components while accounting for the data collection process and making use of auxiliary information. The hierarchical modeling framework allows us to demonstrate how several commonly used species distribution models can be derived from the point process distribution, highlight areas of potential overlap between different models, and suggest areas where further research is needed.

Learning to count begins in infancy: evidence from 18 month olds' visual preferences.

PubMed

Slaughter, Virginia; Itakura, Shoji; Kutsuki, Aya; Siegal, Michael

2011-10-07

We used a preferential looking paradigm to evaluate infants' preferences for correct versus incorrect counting. Infants viewed a video depicting six fish. In the correct counting sequence, a hand pointed to each fish in turn, accompanied by verbal counting up to six. In the incorrect counting sequence, the hand moved between two of the six fish while there was still verbal counting to six, thereby violating the one-to-one correspondence principle of correct counting. Experiment 1 showed that Australian 18 month olds, but not 15 month olds, significantly preferred to watch the correct counting sequence. In experiment 2, Australian infants' preference for correct counting disappeared when the count words were replaced by beeps or by Japanese count words. In experiment 3, Japanese 18 month olds significantly preferred the correct counting video only when counting was in Japanese. These results show that infants start to acquire the abstract principles governing correct counting prior to producing any counting behaviour.

Learning to count begins in infancy: evidence from 18 month olds' visual preferences

PubMed Central

Slaughter, Virginia; Itakura, Shoji; Kutsuki, Aya; Siegal, Michael

2011-01-01

We used a preferential looking paradigm to evaluate infants' preferences for correct versus incorrect counting. Infants viewed a video depicting six fish. In the correct counting sequence, a hand pointed to each fish in turn, accompanied by verbal counting up to six. In the incorrect counting sequence, the hand moved between two of the six fish while there was still verbal counting to six, thereby violating the one-to-one correspondence principle of correct counting. Experiment 1 showed that Australian 18 month olds, but not 15 month olds, significantly preferred to watch the correct counting sequence. In experiment 2, Australian infants' preference for correct counting disappeared when the count words were replaced by beeps or by Japanese count words. In experiment 3, Japanese 18 month olds significantly preferred the correct counting video only when counting was in Japanese. These results show that infants start to acquire the abstract principles governing correct counting prior to producing any counting behaviour. PMID:21325331

A comparison of point-count and mist-net detections of songbirds by habitat and time-of-season

Treesearch

Rich W. Pagen; Frank R., III Thompson; Dirk E. Burhans

2002-01-01

We compared the results of point-count and mist-net surveys during the breeding and post-breeding seasons in four Missouri Ozark habitats: mature upland forest, mature riparian forest, 9- to 10-yr-old upland forest and 3- to 4-yr-old upland forest created by clearcutting. We determined whether differences in abundance estimates among habitats or between breeding and...

How to Quantify Penile Corpus Cavernosum Structures with Histomorphometry: Comparison of Two Methods

PubMed Central

Felix-Patrício, Bruno; De Souza, Diogo Benchimol; Gregório, Bianca Martins; Costa, Waldemar Silva; Sampaio, Francisco José

2015-01-01

The use of morphometrical tools in biomedical research permits the accurate comparison of specimens subjected to different conditions, and the surface density of structures is commonly used for this purpose. The traditional point-counting method is reliable but time-consuming, with computer-aided methods being proposed as an alternative. The aim of this study was to compare the surface density data of penile corpus cavernosum trabecular smooth muscle in different groups of rats, measured by two observers using the point-counting or color-based segmentation method. Ten normotensive and 10 hypertensive male rats were used in this study. Rat penises were processed to obtain smooth muscle immunostained histological slices and photomicrographs captured for analysis. The smooth muscle surface density was measured in both groups by two different observers by the point-counting method and by the color-based segmentation method. Hypertensive rats showed an increase in smooth muscle surface density by the two methods, and no difference was found between the results of the two observers. However, surface density values were higher by the point-counting method. The use of either method did not influence the final interpretation of the results, and both proved to have adequate reproducibility. However, as differences were found between the two methods, results obtained by either method should not be compared. PMID:26413547

How to Quantify Penile Corpus Cavernosum Structures with Histomorphometry: Comparison of Two Methods.

PubMed

Felix-Patrício, Bruno; De Souza, Diogo Benchimol; Gregório, Bianca Martins; Costa, Waldemar Silva; Sampaio, Francisco José

2015-01-01

The use of morphometrical tools in biomedical research permits the accurate comparison of specimens subjected to different conditions, and the surface density of structures is commonly used for this purpose. The traditional point-counting method is reliable but time-consuming, with computer-aided methods being proposed as an alternative. The aim of this study was to compare the surface density data of penile corpus cavernosum trabecular smooth muscle in different groups of rats, measured by two observers using the point-counting or color-based segmentation method. Ten normotensive and 10 hypertensive male rats were used in this study. Rat penises were processed to obtain smooth muscle immunostained histological slices and photomicrographs captured for analysis. The smooth muscle surface density was measured in both groups by two different observers by the point-counting method and by the color-based segmentation method. Hypertensive rats showed an increase in smooth muscle surface density by the two methods, and no difference was found between the results of the two observers. However, surface density values were higher by the point-counting method. The use of either method did not influence the final interpretation of the results, and both proved to have adequate reproducibility. However, as differences were found between the two methods, results obtained by either method should not be compared.

The conservation value of degraded forests for agile gibbons Hylobates agilis.

PubMed

Lee, David C; Powell, Victoria J; Lindsell, Jeremy A

2015-01-01

All gibbon species are globally threatened with extinction yet conservation efforts are undermined by a lack of population and ecological data. Agile gibbons (Hylobates agilis) occur in Sumatra, Indonesia and adjacent mainland Southeast Asia. Population densities are known from four sites (three in Sumatra) while little is known about their ability to tolerate habitat degradation. We conducted a survey of agile gibbons in Harapan Rainforest, a lowland forest site in Sumatra. The area has been severely degraded by selective logging and encroachment but is now managed for ecosystem restoration. We used two survey methods: an established point count method for gibbons with some modifications, and straight line transects using auditory detections. Surveys were conducted in the three main forest types prevalent at the site: high, medium, and low canopy cover secondary forests. Mean group density estimates were higher from point counts than from line transects, and tended to be higher in less degraded forests within the study site. We consider points more time efficient and reliable than transects since detectability of gibbons was higher from points per unit effort. We recommend the additional use of Distance sampling methods to account for imperfect detection and provide other recommendations to improve surveys of gibbons. We estimate that the site holds at least 6,070 and as many as 11,360 gibbons. Our results demonstrate that degraded forests can be extremely important for the conservation of agile gibbons and that efforts to protect and restore such sites could contribute significantly to the conservation of the species. © 2014 Wiley Periodicals, Inc.

7 CFR 51.689 - Tolerances.

Code of Federal Regulations, 2013 CFR

2013-01-01

... at end of Table I] Factor Grades AL 2 Number of 50-count samples 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14... Grades AL 2 Number of 50-count samples 3 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40... port of entry into the United States. 2 AL—Absolute limit permitted in individual 33-count sample. 3...

7 CFR 51.689 - Tolerances.

Code of Federal Regulations, 2014 CFR

2014-01-01

... at end of Table I] Factor Grades AL 2 Number of 50-count samples 3 1 2 3 4 5 6 7 8 9 10 11 12 13 14... Grades AL 2 Number of 50-count samples 3 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40... port of entry into the United States. 2 AL—Absolute limit permitted in individual 33-count sample. 3...

Preliminary calibration of the ACP safeguards neutron counter

NASA Astrophysics Data System (ADS)

Lee, T. H.; Kim, H. D.; Yoon, J. S.; Lee, S. Y.; Swinhoe, M.; Menlove, H. O.

2007-10-01

The Advanced Spent Fuel Conditioning Process (ACP), a kind of pyroprocess, has been developed at the Korea Atomic Energy Research Institute (KAERI). Since there is no IAEA safeguards criteria for this process, KAERI has developed a neutron coincidence counter to make it possible to perform a material control and accounting (MC&A) for its ACP materials for the purpose of a transparency in the peaceful uses of nuclear materials at KAERI. The test results of the ACP Safeguards Neutron Counter (ASNC) show a satisfactory performance for the Doubles count measurement with a low measurement error for its cylindrical sample cavity. The neutron detection efficiency is about 21% with an error of ±1.32% along the axial direction of the cavity. Using two 252Cf neutron sources, we obtained various parameters for the Singles and Doubles rates for the ASNC. The Singles, Doubles, and Triples rates for a 252Cf point source were obtained by using the MCNPX code and the results for the ft8 cap multiplicity tally option with the values of ɛ, fd, and ft measured with a strong source most closely match the measurement results to within a 1% error. A preliminary calibration curve for the ASNC was generated by using the point model equation relationship between 244Cm and 252Cf and the calibration coefficient for the non-multiplying sample is 2.78×10 5 (Doubles counts/s/g 244Cm). The preliminary calibration curves for the ACP samples were also obtained by using an MCNPX simulation. A neutron multiplication influence on an increase of the Doubles rate for a metal ingot and UO2 powder is clearly observed. These calibration curves will be modified and complemented, when hot calibration samples become available. To verify the validity of this calibration curve, a measurement of spent fuel standards for a known 244Cm mass will be performed in the near future.

Quadtree of TIN: a new algorithm of dynamic LOD

NASA Astrophysics Data System (ADS)

Zhang, Junfeng; Fei, Lifan; Chen, Zhen

2009-10-01

Currently, Real-time visualization of large-scale digital elevation model mainly employs the regular structure of GRID based on quadtree and triangle simplification methods based on irregular triangulated network (TIN). TIN is a refined means to express the terrain surface in the computer science, compared with GRID. However, the data structure of TIN model is complex, and is difficult to realize view-dependence representation of level of detail (LOD) quickly. GRID is a simple method to realize the LOD of terrain, but contains more triangle count. A new algorithm, which takes full advantage of the two methods' merit, is presented in this paper. This algorithm combines TIN with quadtree structure to realize the view-dependence LOD controlling over the irregular sampling point sets, and holds the details through the distance of viewpoint and the geometric error of terrain. Experiments indicate that this approach can generate an efficient quadtree triangulation hierarchy over any irregular sampling point sets and achieve dynamic and visual multi-resolution performance of large-scale terrain at real-time.

Somatic cell counts in bulk milk and their importance for milk processing

NASA Astrophysics Data System (ADS)

Savić, N. R.; Mikulec, D. P.; Radovanović, R. S.

2017-09-01

Bulk tank milk somatic cell counts are the indicator of the mammary gland health in the dairy herds and may be regarded as an indirect measure of milk quality. Elevated somatic cell counts are correlated with changes in milk composition The aim of this study was to assess the somatic cell counts that significantly affect the quality of milk and dairy products. We examined the somatic cell counts in bulk tank milk samples from 38 farms during the period of 6 months, from December to the May of the next year. The flow cytometry, Fossomatic was used for determination of somatic cell counts. In the same samples content of total proteins and lactose was determined by Milcoscan. Our results showed that average values for bulk tank milk samples were 273,605/ml from morning milking and 292,895/ml from evening milking. The average values for total proteins content from morning and evening milking are 3,31 and 3,34%, respectively. The average values for lactose content from morning and evening milking are 4,56 and 4,63%, respectively. The highest somatic cell count (516,000/ml) was detected in bulk tank milk sample from evening milk in the Winter and the lowest content of lactose was 4,46%. Our results showed that obtained values for bulk tank milk somatic cell counts did not significantly affected the content of total proteins and lactose.

[Bacteriological quality of traditional, organic and hydroponic cultured lettuce in Costa Rica].

PubMed

Monge, Claudio; Chaves, Carolina; Arias, María Laura

2011-03-01

The main objective of this work was to evaluate the microbiological quality of lettuces commercialized in the Metropolitan Area of San José, Costa Rica, and cultured in different ways, in order to detect differences between the culturing methods and the risk that these products may represent for Public Health. The study was done at the Food Microbiology Laboratory, Universidad de Costa Rica, from March to July, 2010. 30 lettuce samples were analyzed (10 obtained by traditional culture, 10 by organic culture and 10 by hydropony). All samples were obtained from markets where their origin was certified. Total aerobic plate count, total and fecal coliforms count and Escherichia coli were determined to all samples, as well as the presence/abscense of Salmonella spp. and Listeria monocytogenes in 25 g. Results obtained show that there is no statistically significant difference (p < 0.001) between the different types of cultures analyzed for any of the parameters evaluated. An important percentage of the samples presented coliforms, nevertheless, just one E. coli strain was isolated from a traditionally cultured lettuce sample. Four different Salmonella spp. strains were isolated from the samples as well as one Listeria monocytogenes strain. Data obtained show that the consumption of this product, raw or without an adequate hygiene and disinfection may represent a risk for health. Also, from the bacteriological point of view, there is no significant difference between the culturing methods evaluated, suggesting that the specific directions for each type of culture are not followed or that there is an inadequate handling of the products or post harvest contamination.

Validation of time and temperature values as critical limits for the control of Escherichia coli O157:H7 during the production of fresh ground beef.

PubMed

Mann, J E; Brashears, M M

2006-08-01

In order to provide beef processors with valuable data to validate critical limits set for temperature during grinding, a study was conducted to determine Escherichia coli o157:H7 growth at various temperatures in raw ground beef. Fresh ground beef samples were inoculated with a cocktail mixture of streptomycin-resistant E. coli O157:H7 to facilitate recovery in the presence of background flora. Samples were held at 4.4, 7.2, and 10 degrees C, and at room temperature (22.2 to 23.3 degrees C) to mimic typical processing and holding temperatures observed in meat processing environments. E. coli O157:H7 counts were determined by direct plating onto tryptic soy agar with streptomycin (1,000 microg/ml), at 2-h intervals over 12 h for samples held at room temperature. Samples held under refrigeration temperatures were sampled at 4, 8, 12, 24, 48, and 72 h. Less than one log of E. coli O157:H7 growth was observed at 48 h for samples held at 10 degrees C. Samples held at 4.4 and 7.2 degrees C showed less than one log of E. coli O157:H7 growth at 72 h. Samples held at room temperature showed no significant increase in E. coli O157:H7 counts for the first 6 h, but increased significantly afterwards. These results illustrate that meat processors can utilize a variety of time and temperature combinations as critical limits in their hazard analysis critical control point plans to minimize E. coli O157:H7 growth during the production and storage of ground beef.

Modelling habitat associations with fingernail clam (Family: Sphaeriidae) counts at multiple spatial scales using hierarchical count models

USGS Publications Warehouse

Gray, B.R.; Haro, R.J.; Rogala, J.T.; Sauer, J.S.

2005-01-01

1. Macroinvertebrate count data often exhibit nested or hierarchical structure. Examples include multiple measurements along each of a set of streams, and multiple synoptic measurements from each of a set of ponds. With data exhibiting hierarchical structure, outcomes at both sampling (e.g. Within stream) and aggregated (e.g. Stream) scales are often of interest. Unfortunately, methods for modelling hierarchical count data have received little attention in the ecological literature. 2. We demonstrate the use of hierarchical count models using fingernail clam (Family: Sphaeriidae) count data and habitat predictors derived from sampling and aggregated spatial scales. The sampling scale corresponded to that of a standard Ponar grab (0.052 m(2)) and the aggregated scale to impounded and backwater regions within 38-197 km reaches of the Upper Mississippi River. Impounded and backwater regions were resampled annually for 10 years. Consequently, measurements on clams were nested within years. Counts were treated as negative binomial random variates, and means from each resampling event as random departures from the impounded and backwater region grand means. 3. Clam models were improved by the addition of covariates that varied at both the sampling and regional scales. Substrate composition varied at the sampling scale and was associated with model improvements, and reductions (for a given mean) in variance at the sampling scale. Inorganic suspended solids (ISS) levels, measured in the summer preceding sampling, also yielded model improvements and were associated with reductions in variances at the regional rather than sampling scales. ISS levels were negatively associated with mean clam counts. 4. Hierarchical models allow hierarchically structured data to be modelled without ignoring information specific to levels of the hierarchy. In addition, information at each hierarchical level may be modelled as functions of covariates that themselves vary by and within levels. As a result, hierarchical models provide researchers and resource managers with a method for modelling hierarchical data that explicitly recognises both the sampling design and the information contained in the corresponding data.

Attention during active visual tasks: counting, pointing, or simply looking

PubMed Central

Wilder, John D.; Schnitzer, Brian S.; Gersch, Timothy M.; Dosher, Barbara A.

2009-01-01

Visual attention and saccades are typically studied in artificial situations, with stimuli presented to the steadily fixating eye, or saccades made along specified paths. By contrast, in the real world saccadic patterns are constrained only by the demands of the motivating task. We studied attention during pauses between saccades made to perform 3 free-viewing tasks: counting dots, pointing to the same dots with a visible cursor, or simply looking at the dots using a freely-chosen path. Attention was assessed by the ability to identify the orientation of a briefly-presented Gabor probe. All primary tasks produced losses in identification performance, with counting producing the largest losses, followed by pointing and then looking-only. Looking-only resulted in a 37% increase in contrast thresholds in the orientation task. Counting produced more severe losses that were not overcome by increasing Gabor contrast. Detection or localization of the Gabor, unlike identification, were largely unaffected by any of the primary tasks. Taken together, these results show that attention is required to control saccades, even with freely-chosen paths, but the attentional demands of saccades are less than those attached to tasks such as counting, which have a significant cognitive load. Counting proved to be a highly demanding task that either exhausted momentary processing capacity (e.g., working memory or executive functions), or, alternatively, encouraged a strategy of filtering out all signals irrelevant to counting itself. The fact that the attentional demands of saccades (as well as those of detection/localization) are relatively modest makes it possible to continually adjust both the spatial and temporal pattern of saccades so as to re-allocate attentional resources as needed to handle the complex and multifaceted demands of real-world environments. PMID:18649913

The prevalence of abnormal leukocyte count, and its predisposing factors, in patients with sickle cell disease in Saudi Arabia.

PubMed

Ahmed, Anwar E; Ali, Yosra Z; Al-Suliman, Ahmad M; Albagshi, Jafar M; Al Salamah, Majid; Elsayid, Mohieldin; Alanazi, Wala R; Ahmed, Rayan A; McClish, Donna K; Al-Jahdali, Hamdan

2017-01-01

High white blood cell (WBC) count is an indicator of sickle cell disease (SCD) severity, however, there are limited studies on WBC counts in Saudi Arabian patients with SCD. The aim of this study was to estimate the prevalence of abnormal leukocyte count (either low or high) and identify factors associated with high WBC counts in a sample of Saudi patients with SCD. A cross-sectional and retrospective chart review study was carried out on 290 SCD patients who were routinely treated at King Fahad Hospital in Hofuf, Saudi Arabia. An interview was conducted to assess clinical presentations, and we reviewed patient charts to collect data on blood test parameters for the previous 6 months. Almost half (131 [45.2%]) of the sample had abnormal leukocyte counts: low WBC counts 15 (5.2%) and high 116 (40%). High WBC counts were associated with shortness of breath ( P =0.022), tiredness ( P =0.039), swelling in hands/feet ( P =0.020), and back pain ( P =0.007). The mean hemoglobin was higher in patients with normal WBC counts ( P =0.024), while the mean hemoglobin S was high in patients with high WBC counts ( P =0.003). After adjustment for potential confounders, predictors of high WBC counts were male gender (adjusted odds ratio [aOR]=3.63) and patients with cough (aOR=2.18), low hemoglobin (aOR=0.76), and low heart rate (aOR=0.97). Abnormal leukocyte count was common: approximately five in ten Saudi SCD patients assessed in this sample. Male gender, cough, low hemoglobin, and low heart rate were associated with high WBC count. Strategies targeting high WBC count could prevent disease complication and thus could be beneficial for SCD patients.

Conclusions on measurement uncertainty in microbiology.

PubMed

Forster, Lynne I

2009-01-01

Since its first issue in 1999, testing laboratories wishing to comply with all the requirements of ISO/IEC 17025 have been collecting data for estimating uncertainty of measurement for quantitative determinations. In the microbiological field of testing, some debate has arisen as to whether uncertainty needs to be estimated for each method performed in the laboratory for each type of sample matrix tested. Queries also arise concerning the estimation of uncertainty when plate/membrane filter colony counts are below recommended method counting range limits. A selection of water samples (with low to high contamination) was tested in replicate with the associated uncertainty of measurement being estimated from the analytical results obtained. The analyses performed on the water samples included total coliforms, fecal coliforms, fecal streptococci by membrane filtration, and heterotrophic plate counts by the pour plate technique. For those samples where plate/membrane filter colony counts were > or =20, uncertainty estimates at a 95% confidence level were very similar for the methods, being estimated as 0.13, 0.14, 0.14, and 0.12, respectively. For those samples where plate/membrane filter colony counts were <20, estimated uncertainty values for each sample showed close agreement with published confidence limits established using a Poisson distribution approach.

The Navy Medical Department’s Workload Management System for Nursing (Patient Classification and Staffing Allocation). Self-Instructional Workbook

DTIC Science & Technology

1986-01-01

minal area, assess fetal heart tones with stethoscope , record FHTs, and remove equipment from area. or . Fetal Heart Tones, Doppler: Includes time to...activity to total 4 points. 5. Femoral OR pedal pulses OR fetal heart tones must be taken q 4 h . before you count the 2 points, but once again, since the... fetal heart tones OR tilt tests will count 2 points each if doneq 4 h or more frequently. If you had a patient with pedal pulses q 4 h AND fetal heart

Promotion of Physical Activity Using Point-of-Decision Prompts in Berlin Underground Stations

PubMed Central

Müller-Riemenschneider, Falk; Nocon, Marc; Reinhold, Thomas; Willich, Stefan N.

2010-01-01

To evaluate point-of-decision prompts in the promotion of stair use in Germany, motivational posters were placed at three underground stations in Berlin. The proportion of passengers using stairs or stairways was counted before, during installation, and two weeks after removal of posters. In total, 5,467 passersby were counted. Stair use increased significantly in women, but not in men. The present pilot study thereby shows that the use of point-of-decision prompts is also feasible in Germany and it provides some evidence of effectiveness. Methodologically rigorous studies are warranted to confirm these findings. PMID:20948947

A Semiparametric Change-Point Regression Model for Longitudinal Observations.

PubMed

Xing, Haipeng; Ying, Zhiliang

2012-12-01

Many longitudinal studies involve relating an outcome process to a set of possibly time-varying covariates, giving rise to the usual regression models for longitudinal data. When the purpose of the study is to investigate the covariate effects when experimental environment undergoes abrupt changes or to locate the periods with different levels of covariate effects, a simple and easy-to-interpret approach is to introduce change-points in regression coefficients. In this connection, we propose a semiparametric change-point regression model, in which the error process (stochastic component) is nonparametric and the baseline mean function (functional part) is completely unspecified, the observation times are allowed to be subject-specific, and the number, locations and magnitudes of change-points are unknown and need to be estimated. We further develop an estimation procedure which combines the recent advance in semiparametric analysis based on counting process argument and multiple change-points inference, and discuss its large sample properties, including consistency and asymptotic normality, under suitable regularity conditions. Simulation results show that the proposed methods work well under a variety of scenarios. An application to a real data set is also given.

The impact of dairy cows' bedding material and its microbial content on the quality and safety of milk - A cross sectional study of UK farms.

PubMed

Bradley, Andrew J; Leach, Katharine A; Green, Martin J; Gibbons, Jenny; Ohnstad, Ian C; Black, David H; Payne, Barbara; Prout, Victoria E; Breen, James E

2018-03-23

The introduction of bedding dairy cows on recycled manure solids (RMS) in the UK led to concern by competent authorities that there could be an increased, unacceptable risk to animal and human health. A cross-sectional study was designed to evaluate the microbial content of different bedding materials, when used by dairy cows, and its impact on the microbial content of milk. Data were collected from farms bedding lactating cows on sand (n=41), sawdust (n=44) and RMS (n=40). The mean duration of RMS use prior to sampling was 13months. Total bacterial count, and counts of Streptococcus/Enterococcus spp., Staphylococcus spp., Bacillus cereus, thermophilic, thermoduric and psychrotrophic bacteria were determined in used bedding and milk. Samples were evaluated for the presence/absence of Listeria monocytogenes, Salmonella spp. and Yersinia enterocolitica. Data on milking practices were collected to investigate their potential to reduce microbial transfer from bedding to milk. There were substantial differences in bacterial counts both within and between bedding materials. However, there were no significant differences between bedding groups in counts in milk for any of the organisms studied, and no significant correlations between bacterial load in used bedding and milk. Fore-milking was associated with a reduced total bacterial count in milk. Dipping teats with disinfectant and drying, prior to milking, was associated with lower numbers of Streptococcus/Enterococcus spp. in milk. Disinfecting clusters between milking different cows was associated with a reduction in thermophilic and psychrotrophic counts in milk. This study did not provide evidence that use of RMS bedding increased the risk of presence of Y. enterocolitica, Salmonella spp. or L. monocytogenes in milk. However, the strength of this conclusion should be tempered by the relatively small number of farms on which Y. enterocolitica and Salmonella spp. were isolated. It is concluded that, despite the higher bacterial load of RMS, its use as bedding for lactating dairy cows need not be associated with a higher bacterial load in milk than the use of sand or sawdust. However, this finding must be interpreted in the light of the relatively recent introduction of RMS as a bedding material on the farms studied. Teat preparation provides a control point for the potential transfer of microorganisms from bedding to milk. The detection of zoonotic pathogens in a small proportion of milk samples, independent of bedding type, indicates that pasteurisation of milk prior to human consumption remains an important control measure. Copyright © 2017 Elsevier B.V. All rights reserved.

Characterization Results for the March 2016 H-Tank Farm 2H Evaporator Overhead Samples

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

Nicholson, J. C.

This report contains the radioanalytical results of the 2H evaporator overhead sample received at SRNL on March 16, 2016. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits. Revision 1 of this document corrects the cumulative beta count initially reported for 90Sr content with the sole 90Sr count obtained after recharacterization of the sample. The initial data wasmore » found to be a cumulative beta count rather than the 90Sr count requested.« less

Regression Analysis of Mixed Panel Count Data with Dependent Terminal Events

PubMed Central

Yu, Guanglei; Zhu, Liang; Li, Yang; Sun, Jianguo; Robison, Leslie L.

2017-01-01

Event history studies are commonly conducted in many fields and a great deal of literature has been established for the analysis of the two types of data commonly arising from these studies: recurrent event data and panel count data. The former arises if all study subjects are followed continuously, while the latter means that each study subject is observed only at discrete time points. In reality, a third type of data, a mixture of the two types of the data above, may occur and furthermore, as with the first two types of the data, there may exist a dependent terminal event, which may preclude the occurrences of recurrent events of interest. This paper discusses regression analysis of mixed recurrent event and panel count data in the presence of a terminal event and an estimating equation-based approach is proposed for estimation of regression parameters of interest. In addition, the asymptotic properties of the proposed estimator are established and a simulation study conducted to assess the finite-sample performance of the proposed method suggests that it works well in practical situations. Finally the methodology is applied to a childhood cancer study that motivated this study. PMID:28098397

Excreta Sampling as an Alternative to In Vivo Measurements at the Hanford Site.

PubMed

Carbaugh, Eugene H; Antonio, Cheryl L; Lynch, Timothy P

2015-08-01

The capabilities of indirect radiobioassay by urine and fecal sample analysis were compared with the direct radiobioassay methods of whole body counting and lung counting for the most common radionuclides and inhalation exposure scenarios encountered by Hanford workers. Radionuclides addressed by in vivo measurement included 137Cs, 60Co, 154Eu, and 241Am as an indicator for plutonium mixtures. The same radionuclides were addressed using gamma energy analysis of urine samples, augmented by radiochemistry and alpha spectrometry methods for plutonium in urine and fecal samples. It was concluded that in vivo whole body counting and lung counting capability should be maintained at the Hanford Site for the foreseeable future, however, urine and fecal sample analysis could provide adequate, though degraded, monitoring capability for workers as a short-term alternative, should in vivo capability be lost due to planned or unplanned circumstances.

Does the Coordination of Verbal and Motor Information Explain the Development of Counting in Children?

ERIC Educational Resources Information Center

Camos, Valerie; Barrouillet, Pierre; Fayol, Michel

2001-01-01

Tested in three experiments hypothesis that coordinating saying number-words and pointing to each object to count requires use of the central executive and that cost of coordination decreases with age. Found that for 5- and 9-year-olds and adults, manipulating difficulty of each component affected counting performance but did not make coordination…

The counting abilities of children with specific language impairment: a comparison of oral and gestural tasks.

PubMed

Fazio, B B

1994-04-01

This study examined the counting abilities of preschool children with specific language impairment compared to language-matched and mental-age-matched peers. In order to determine the nature of the difficulties SLI children exhibited in counting, the subjects participated in a series of oral counting tasks and a series of gestural tasks that used an invented counting system based on pointing to body parts. Despite demonstrating knowledge of many of the rules associated with counting, SLI preschool children displayed marked difficulty in counting objects. On oral counting tasks, they showed difficulty with rote counting, displayed a limited repertoire of number terms, and miscounted sets of objects. However, on gestural counting tasks, SLI children's performance was significantly better. These findings suggest that SLI children have a specific difficulty with the rote sequential aspect of learning number words.

What Can Quantum Optics Say about Computational Complexity Theory?

NASA Astrophysics Data System (ADS)

Rahimi-Keshari, Saleh; Lund, Austin P.; Ralph, Timothy C.

2015-02-01

Considering the problem of sampling from the output photon-counting probability distribution of a linear-optical network for input Gaussian states, we obtain results that are of interest from both quantum theory and the computational complexity theory point of view. We derive a general formula for calculating the output probabilities, and by considering input thermal states, we show that the output probabilities are proportional to permanents of positive-semidefinite Hermitian matrices. It is believed that approximating permanents of complex matrices in general is a #P-hard problem. However, we show that these permanents can be approximated with an algorithm in the BPPNP complexity class, as there exists an efficient classical algorithm for sampling from the output probability distribution. We further consider input squeezed-vacuum states and discuss the complexity of sampling from the probability distribution at the output.

Point-of-care blood eosinophil count in a severe asthma clinic setting.

PubMed

Heffler, Enrico; Terranova, Giovanni; Chessari, Carlo; Frazzetto, Valentina; Crimi, Claudia; Fichera, Silvia; Picardi, Giuseppe; Nicolosi, Giuliana; Porto, Morena; Intravaia, Rossella; Crimi, Nunzio

2017-07-01

One of the main severe asthma phenotypes is severe eosinophilic or eosinophilic refractory asthma for which novel biologic agents are emerging as therapeutic options. In this context, blood eosinophil counts are one of the most reliable biomarkers. To evaluate the performance of a point-of-care peripheral blood counter in a patients with severe asthma. The blood eosinophil counts of 76 patients with severe asthma were evaluated by point-of-care and standard analyzers. A significant correlation between blood eosinophils assessed by the 2 devices was found (R 2  = 0.854, P < .001); similar correlations were found also for white blood cells, neutrophils, and lymphocytes. The point-of-care device had the ability to predict blood eosinophil cutoffs used to select patients for biologic treatments for severe eosinophilic asthma and the ELEN index, a composite score useful to predict sputum eosinophilia. The results of our study contribute to the validation of a point-of-care device to assess blood eosinophils and open the possibility of using this device for the management of severe asthma management. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

A proposed method to minimize waste from institutional radiation safety surveillance programs through the application of expected value statistics.

PubMed

Emery, R J

1997-03-01

Institutional radiation safety programs routinely use wipe test sampling and liquid scintillation counting analysis to indicate the presence of removable radioactive contamination. Significant volumes of liquid waste can be generated by such surveillance activities, and the subsequent disposal of these materials can sometimes be difficult and costly. In settings where large numbers of negative results are regularly obtained, the limited grouping of samples for analysis based on expected value statistical techniques is possible. To demonstrate the plausibility of the approach, single wipe samples exposed to varying amounts of contamination were analyzed concurrently with nine non-contaminated samples. Although the sample grouping inevitably leads to increased quenching with liquid scintillation counting systems, the effect did not impact the ability to detect removable contamination in amounts well below recommended action levels. Opportunities to further improve this cost effective semi-quantitative screening procedure are described, including improvements in sample collection procedures, enhancing sample-counting media contact through mixing and extending elution periods, increasing sample counting times, and adjusting institutional action levels.

The displacement of the sun from the galactic plane using IRAS and faust source counts

NASA Technical Reports Server (NTRS)

Cohen, Martin

1995-01-01

I determine the displacement of the Sun from the Galactic plane by interpreting IRAS point-source counts at 12 and 25 microns in the Galactic polar caps using the latest version of the SKY model for the point-source sky (Cohen 1994). A value of solar zenith = 15.5 +/- 0.7 pc north of the plane provides the best match to the ensemble of useful IRAS data. Shallow K counts in the north Galactic pole are also best fitted by this offset, while limited FAUST far-ultraviolet counts at 1660 A near the same pole favor a value near 14 pc. Combining the many IRAS determinations with the few FAUST values suggests that a value of solar zenith = 15.0 +/- 0.5 pc (internal error only) would satisfy these high-latitude sets of data in both wavelength regimes, within the context of the SKY model.

Characterization of HPGe gamma spectrometric detectors systems for Instrumental Neutron Activation Analysis (INAA) at the Colombian Geological Survey

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

Sierra, O., E-mail: osierra@sgc.gov.co; Parrado, G., E-mail: gparrado@sgc.gov.co; Cañón, Y.

This paper presents the progress made by the Neutron Activation Analysis (NAA) laboratory at the Colombian Geological Survey (SGC in its Spanish acronym), towards the characterization of its gamma spectrometric systems for Instrumental Neutron Activation Analysis (INAA), with the aim of introducing corrections to the measurements by variations in sample geometry. Characterization includes the empirical determination of the interaction point of gamma radiation inside the Germanium crystal, through the application of a linear model and the use of a fast Monte Carlo N-Particle (MCNP) software to estimate correction factors for differences in counting efficiency that arise from variations in samplemore » density between samples and standards.« less

Interobserver variation in the diagnosis of fibroepithelial lesions of the breast: a multicentre audit by digital pathology.

PubMed

Dessauvagie, Benjamin F; Lee, Andrew H S; Meehan, Katie; Nijhawan, Anju; Tan, Puay Hoon; Thomas, Jeremy; Tie, Bibiana; Treanor, Darren; Umar, Seemeen; Hanby, Andrew M; Millican-Slater, Rebecca

2018-02-13

Fibroepithelial lesions (FELs) of the breast span a morphological continuum including lesions where distinction between cellular fibroadenoma (FA) and benign phyllodes tumour (PT) is difficult. The distinction is clinically important with FAs managed conservatively while equivocal lesions and PTs are managed with surgery. We sought to audit core biopsy diagnoses of equivocal FELs by digital pathology and to investigate whether digital point counting is useful in clarifying FEL diagnoses. Scanned slide images from cores and subsequent excisions of 69 equivocal FELs were examined in a multicentre audit by eight pathologists to determine the agreement and accuracy of core needle biopsy (CNB) diagnoses and by digital point counting of stromal cellularity and expansion to determine if classification could be improved. Interobserver variation was high on CNB with a unanimous diagnosis from all pathologists in only eight cases of FA, diagnoses of both FA and PT on the same CNB in 15 and a 'weak' mean kappa agreement between pathologists (k=0.36). 'Moderate' agreement was observed on CNBs among breast specialists (k=0.44) and on excision samples (k=0.49). Up to 23% of lesions confidently diagnosed as FA on CNB were PT on excision and up to 30% of lesions confidently diagnosed as PT on CNB were FA on excision. Digital point counting did not aid in the classification of FELs. Accurate and reproducible diagnosis of equivocal FELs is difficult, particularly on CNB, resulting in poor interobserver agreement and suboptimal accuracy. Given the diagnostic difficulty, and surgical implications, equivocal FELs should be reported in consultation with experienced breast pathologists as a small number of benign FAs can be selected out from equivocal lesions. © 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.

Multiplicity Counting

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

Geist, William H.

2015-12-01

This set of slides begins by giving background and a review of neutron counting; three attributes of a verification item are discussed: 240Pu eff mass; α, the ratio of (α,n) neutrons to spontaneous fission neutrons; and leakage multiplication. It then takes up neutron detector systems – theory & concepts (coincidence counting, moderation, die-away time); detector systems – some important details (deadtime, corrections); introduction to multiplicity counting; multiplicity electronics and example distributions; singles, doubles, and triples from measured multiplicity distributions; and the point model: multiplicity mathematics.

Assessment of drinking water quality using ICP-MS and microbiological methods in the Bholakpur area, Hyderabad, India.

PubMed

Abdul, Rasheed M; Mutnuri, Lakshmi; Dattatreya, Patil J; Mohan, Dayal A

2012-03-01

A total of 16 people died and over 500 people were hospitalized due to diarrhoeal illness in the Bholakpur area of Hyderabad, India on 6th May 2009. A study was conducted with immediate effect to evaluate the quality of municipal tap water of the Bholakpur locality. The study consists of the determination of physico-chemical properties, trace metals, heavy metals, rare earth elements and microbiological quality of drinking water. The data showed the variation of the investigated parameters in samples as follows: pH 7.14 to 8.72, EC 455 to 769 μS/cm, TDS 303.51 to 515.23 ppm and DO 1.01 to 6.83 mg/L which are within WHO guidelines for drinking water quality. The water samples were analyzed for 27 elements (Li, Be, B, Na, Mg, Al, Si, K, Ca, V, Cr, Mn, Fe, Ni, Co, Cu, Zn, As, Se, Rb, Sr, Mo, Ag, Cd, Sb, Ba and Pb) using inductively coupled plasma-mass spectrometry (ICP-MS). The concentrations of Fe (0.12 to 1.13 mg/L), Pb (0.01 to 0.07 mg/L), Cu (0.01 to 0.19 mg/L), Ni (0.01 to 0.15 mg/L), Al (0.16 to 0.49 mg/L), and Na (38.36 to 68.69 mg/L) were obtained, which exceed the permissible limits of the World Health Organization (WHO) for drinking water quality guidelines. The remaining elements were within the permissible limits. The microbiological quality of water was tested using standard plate count, membrane filtration technique, thermotolerant coliform (TTC), and most probable number (MPN) methods. The total heterotrophic bacteria ranged from 1.0 × 10(5) to 18 × 10(7 )cfu/ml. Total viable bacteria in all the water samples were found to be too numerable to count and total number of coliform bacteria in all water samples were found to be of order of 1,100 to >2,400 MPN index/100 ml. TTC tested positive for coliform bacteria at 44.2°C. All the water samples of the study area exceeded the permissible counts of WHO and that (zero and minimal counts) of the control site (National Geophysical Research Institute) water samples. Excessively high colony numbers indicate that the water is highly contaminated with microorganisms and is hazardous for drinking purposes. Bacteriological pollution of drinking water supplies caused diarrhoeal illness in Bholakpur, which is due to the infiltration of contaminated water (sewage) through cross connection, leakage points, and back siphoning.

Survival of Staphylococcus pseudintermedius in modified Romanowsky staining solutions.

PubMed

Misan, Angus; Chan, Wei Yee; Trott, Darren; Hill, Peter B

2017-08-01

Stains that are used regularly for patient-side diagnosis to rapidly identify bacterial and fungal infections could become contaminated by common pathogens, such as Staphylococcus pseudintermedius, during slide immersion. To determine whether the inoculation of S. pseudintermedius into modified Romanowsky type stains (Quick Dip ® ) results in viable bacterial contamination and whether this is influenced by the addition of organic debris (canine hair and skin). A clinical isolate of S. pseudintermedius was inoculated into clean and organically contaminated Quick Dip ® solutions (methanol fixative, eosin, methylene blue), and positive (broth) and negative (bleach) controls. Each solution was tested for the presence of viable bacteria by counting the number of colony forming units (CFU/mL) at various time points. Solutions also were examined under high power microscopy to count the number of visible bacteria at each time point. Staphylococcus pseudintermedius was able to survive in the clean and contaminated Quick Dip ® stains for at least one hour, but by 24 h no viable bacteria remained. Survival of the bacteria was not supported in the fixative at any time point. Staphylococcus pseudintermedius remained visible under high power microscopy for up to 2 weeks in all organically contaminated solutions of the Quick Dip ® set. Staphylococcus pseudintermedius only remains viable in eosin and methylene blue for short periods of time, but the prolonged visibility of dead organisms could theoretically lead to the misdiagnosis of cytology samples. © 2017 ESVD and ACVD.

Compton suppression gamma-counting: The effect of count rate

USGS Publications Warehouse

Millard, H.T.

1984-01-01

Past research has shown that anti-coincidence shielded Ge(Li) spectrometers enhanced the signal-to-background ratios for gamma-photopeaks, which are situated on high Compton backgrounds. Ordinarily, an anti- or non-coincidence spectrum (A) and a coincidence spectrum (C) are collected simultaneously with these systems. To be useful in neutron activation analysis (NAA), the fractions of the photopeak counts routed to the two spectra must be constant from sample to sample to variations must be corrected quantitatively. Most Compton suppression counting has been done at low count rate, but in NAA applications, count rates may be much higher. To operate over the wider dynamic range, the effect of count rate on the ratio of the photopeak counts in the two spectra (A/C) was studied. It was found that as the count rate increases, A/C decreases for gammas not coincident with other gammas from the same decay. For gammas coincident with other gammas, A/C increases to a maximum and then decreases. These results suggest that calibration curves are required to correct photopeak areas so quantitative data can be obtained at higher count rates. ?? 1984.

Estimating abundance while accounting for rarity, correlated behavior, and other sources of variation in counts

USGS Publications Warehouse

Dorazio, Robert M.; Martin, Juulien; Edwards, Holly H.

2013-01-01

The class of N-mixture models allows abundance to be estimated from repeated, point count surveys while adjusting for imperfect detection of individuals. We developed an extension of N-mixture models to account for two commonly observed phenomena in point count surveys: rarity and lack of independence induced by unmeasurable sources of variation in the detectability of individuals. Rarity increases the number of locations with zero detections in excess of those expected under simple models of abundance (e.g., Poisson or negative binomial). Correlated behavior of individuals and other phenomena, though difficult to measure, increases the variation in detection probabilities among surveys. Our extension of N-mixture models includes a hurdle model of abundance and a beta-binomial model of detectability that accounts for additional (extra-binomial) sources of variation in detections among surveys. As an illustration, we fit this model to repeated point counts of the West Indian manatee, which was observed in a pilot study using aerial surveys. Our extension of N-mixture models provides increased flexibility. The effects of different sets of covariates may be estimated for the probability of occurrence of a species, for its mean abundance at occupied locations, and for its detectability.

Estimating abundance while accounting for rarity, correlated behavior, and other sources of variation in counts.

PubMed

Dorazio, Robert M; Martin, Julien; Edwards, Holly H

2013-07-01

The class of N-mixture models allows abundance to be estimated from repeated, point count surveys while adjusting for imperfect detection of individuals. We developed an extension of N-mixture models to account for two commonly observed phenomena in point count surveys: rarity and lack of independence induced by unmeasurable sources of variation in the detectability of individuals. Rarity increases the number of locations with zero detections in excess of those expected under simple models of abundance (e.g., Poisson or negative binomial). Correlated behavior of individuals and other phenomena, though difficult to measure, increases the variation in detection probabilities among surveys. Our extension of N-mixture models includes a hurdle model of abundance and a beta-binomial model of detectability that accounts for additional (extra-binomial) sources of variation in detections among surveys. As an illustration, we fit this model to repeated point counts of the West Indian manatee, which was observed in a pilot study using aerial surveys. Our extension of N-mixture models provides increased flexibility. The effects of different sets of covariates may be estimated for the probability of occurrence of a species, for its mean abundance at occupied locations, and for its detectability.

Seasonal variation of different microorganisms with nickel and cadmium in the industrial wastewater and agricultural soils.

PubMed

Ansari, Mohd Ikram; Malik, Abdul

2010-08-01

Wastewater and soil samples were collected from the industrial area of Ghaziabad City, India from January 2005 to December 2007 and were analyzed for the presence of heavy metals by atomic absorption spectrophotometry. Test samples revealed high levels of Fe, Cr, Cu, Ni, Zn, and Cd as 967.03, 34.63, 27.97, 19.7, 16.70, and 3.20 mg/L of wastewater, respectively. The concentrations of inorganic minerals were higher in the soil samples irrigated with wastewater. Total coliforms were found to be maximum (1,133x10(4) most probable number per 100 mL) during spring and summer followed by winter and postmonsoon in the wastewater samples. The microbial count in soil as well as in wastewater decreases as the metal concentration increases. The concentration 200 microg/mL of nickel and cadmium inhibits majority of the population, while, at some points, it inhibits 100% of the population. The exponential decay model for microbial count at the increasing metal concentrations indicate that asymbiotic N2 fixers were best fitted to the model. In all the seasons, the order of decline in terms of exponential decay of the population of different microbial groups in soil was asymbiotic N2 fixers>actinomycetes>fungi>aerobic heterotrophic bacteria. The different microbial groups that have different values of slope in different seasons indicate that the resistant population of microorganisms was variable with seasons.

Simulation on Poisson and negative binomial models of count road accident modeling

NASA Astrophysics Data System (ADS)

Sapuan, M. S.; Razali, A. M.; Zamzuri, Z. H.; Ibrahim, K.

2016-11-01

Accident count data have often been shown to have overdispersion. On the other hand, the data might contain zero count (excess zeros). The simulation study was conducted to create a scenarios which an accident happen in T-junction with the assumption the dependent variables of generated data follows certain distribution namely Poisson and negative binomial distribution with different sample size of n=30 to n=500. The study objective was accomplished by fitting Poisson regression, negative binomial regression and Hurdle negative binomial model to the simulated data. The model validation was compared and the simulation result shows for each different sample size, not all model fit the data nicely even though the data generated from its own distribution especially when the sample size is larger. Furthermore, the larger sample size indicates that more zeros accident count in the dataset.

Overestimating Fish Counts by Non-Instantaneous Visual Censuses: Consequences for Population and Community Descriptions

PubMed Central

Ward-Paige, Christine; Mills Flemming, Joanna; Lotze, Heike K.

2010-01-01

Background Increasingly, underwater visual censuses (UVC) are used to assess fish populations. Several studies have demonstrated the effectiveness of protected areas for increasing fish abundance or provided insight into the natural abundance and structure of reef fish communities in remote areas. Recently, high apex predator densities (>100,000 individuals·km−2) and biomasses (>4 tonnes·ha−1) have been reported for some remote islands suggesting the occurrence of inverted trophic biomass pyramids. However, few studies have critically evaluated the methods used for sampling conspicuous and highly mobile fish such as sharks. Ideally, UVC are done instantaneously, however, researchers often count animals that enter the survey area after the survey has started, thus performing non-instantaneous UVC. Methodology/Principal Findings We developed a simulation model to evaluate counts obtained by divers deploying non-instantaneous belt-transect and stationary-point-count techniques. We assessed how fish speed and survey procedure (visibility, diver speed, survey time and dimensions) affect observed fish counts. Results indicate that the bias caused by fish speed alone is huge, while survey procedures had varying effects. Because the fastest fishes tend to be the largest, the bias would have significant implications on their biomass contribution. Therefore, caution is needed when describing abundance, biomass, and community structure based on non-instantaneous UVC, especially for highly mobile species such as sharks. Conclusions/Significance Based on our results, we urge that published literature state explicitly whether instantaneous counts were made and that survey procedures be accounted for when non-instantaneous counts are used. Using published density and biomass values of communities that include sharks we explore the effect of this bias and suggest that further investigation may be needed to determine pristine shark abundances and the existence of inverted biomass pyramids. Because such studies are used to make important management and conservation decisions, incorrect estimates of animal abundance and biomass have serious and significant implications. PMID:20661304

Perfect count: a novel approach for the single platform enumeration of absolute CD4+ T-lymphocytes.

PubMed

Storie, Ian; Sawle, Alex; Goodfellow, Karen; Whitby, Liam; Granger, Vivian; Ward, Rosalie Y; Peel, Janet; Smart, Theresa; Reilly, John T; Barnett, David

2004-01-01

The derivation of reliable CD4(+) T lymphocyte counts is vital for the monitoring of disease progression and therapeutic effectiveness in HIV(+) individuals. Flow cytometry has emerged as the method of choice for CD4(+) T lymphocyte enumeration, with single-platform technology, coupled with reference counting beads, fast becoming the "gold standard." However, although single-platform, bead-based, sample acquisition requires the ratio of beads to cells to remain unchanged, there is no available method, until recently, to monitor this. Perfect Count beads have been developed to address this issue and to incorporate two bead populations, with different densities, to allow the detection of inadequate mixing. Comparison of the relative proportions of both beads with the manufacture's defined limits enables an internal QC check during sample acquisition. In this study, we have compared CD4(+) T lymphocyte counts, obtained from 104 HIV(+) patients, using TruCount beads with MultiSet software (defined as the predicated method) and the new Perfect Count beads, incorporating an in house sequential gating strategy. We have demonstrated an excellent degree of correlation between the predicate method and the Perfect Count system (r(2) = 0.9955; Bland Altman bias +27 CD4(+) T lymphocytes/microl). The Perfect Count system is a robust method for performing single platform absolute counts and has the added advantage of having internal QC checks. Such an approach enables the operator to identify potential problems during sample preparation, acquisition and analysis. Copyright 2003 Wiley-Liss, Inc.

Comparison of hematologic values in blood samples with lithium heparin or dipotassium ethylenediaminetetraacetic acid anticoagulants in Hispaniolan Amazon parrots (Amazona ventralis).

PubMed

Guzman, David Sanchez-Migallon; Mitchell, Mark A; Gaunt, Stephen D; Beaufrère, Hugues; Tully, Thomas N

2008-06-01

Blood samples were collected from 20 Hispaniolan Amazon parrots (Amazona ventralis) and were divided into tubes that contained dipotassium ethylenediaminetetraacetic acid (K2EDTA) and lithium heparin. Complete blood cell counts were determined in each sample within 2 hours of collection. The level of agreement in results was moderate for plasma protein, packed cell volume (PCV), and leukocyte, monocyte, and lymphocyte counts between the anticoagulants. Plasma protein and PCV values were significantly lower in samples with lithium heparin than in those with K2EDTA, whereas lymphocyte numbers were significantly higher in lithium heparin samples than in K2EDTA samples. The level of agreement was good for the other cell types (heterophils, eosinophils, and basophils) when comparing the different anticoagulants. The poor level of agreement between anticoagulants with the increase in thrombocyte clumping in lithium heparin samples indicates that the use of lithium heparin as anticoagulant may affect thrombocyte count. No negative effects on morphology and staining of blood cells were apparent in smears from heparin samples compared with K2EDTA samples. Within the different values compared, the limits of agreement are small enough to be confident that lithium heparin can be used for routine CBC counts in a clinical setting. The use of the same anticoagulant should be recommended to follow trends within the same patient, especially when considering plasma protein concentration, PCV, and lymphocyte count.

A new framework of statistical inferences based on the valid joint sampling distribution of the observed counts in an incomplete contingency table.

PubMed

Tian, Guo-Liang; Li, Hui-Qiong

2017-08-01

Some existing confidence interval methods and hypothesis testing methods in the analysis of a contingency table with incomplete observations in both margins entirely depend on an underlying assumption that the sampling distribution of the observed counts is a product of independent multinomial/binomial distributions for complete and incomplete counts. However, it can be shown that this independency assumption is incorrect and can result in unreliable conclusions because of the under-estimation of the uncertainty. Therefore, the first objective of this paper is to derive the valid joint sampling distribution of the observed counts in a contingency table with incomplete observations in both margins. The second objective is to provide a new framework for analyzing incomplete contingency tables based on the derived joint sampling distribution of the observed counts by developing a Fisher scoring algorithm to calculate maximum likelihood estimates of parameters of interest, the bootstrap confidence interval methods, and the bootstrap testing hypothesis methods. We compare the differences between the valid sampling distribution and the sampling distribution under the independency assumption. Simulation studies showed that average/expected confidence-interval widths of parameters based on the sampling distribution under the independency assumption are shorter than those based on the new sampling distribution, yielding unrealistic results. A real data set is analyzed to illustrate the application of the new sampling distribution for incomplete contingency tables and the analysis results again confirm the conclusions obtained from the simulation studies.

A conceptual guide to detection probability for point counts and other count-based survey methods

Treesearch

D. Archibald McCallum

2005-01-01

Accurate and precise estimates of numbers of animals are vitally needed both to assess population status and to evaluate management decisions. Various methods exist for counting birds, but most of those used with territorial landbirds yield only indices, not true estimates of population size. The need for valid density estimates has spawned a number of models for...

Comparison of methods for estimating density of forest songbirds from point counts

Treesearch

Jennifer L. Reidy; Frank R. Thompson; J. Wesley. Bailey

2011-01-01

New analytical methods have been promoted for estimating the probability of detection and density of birds from count data but few studies have compared these methods using real data. We compared estimates of detection probability and density from distance and time-removal models and survey protocols based on 5- or 10-min counts and outer radii of 50 or 100 m. We...

Clostridium perfringens and somatic coliphages as indicators of the efficiency of drinking water treatment for viruses and protozoan cysts.

PubMed Central

Payment, P; Franco, E

1993-01-01

To find the most suitable indicator of viral and parasitic contamination of drinking water, large-volume samples were collected and analyzed for the presence of pathogens (cultivable human enteric viruses, Giardia lamblia cysts, and Cryptosporidium oocysts) and potential indicators (somatic and male-specific coliphages, Clostridium perfringens). The samples were obtained from three water treatment plants by using conventional or better treatments (ozonation, biological filtration). All samples of river water contained the microorganisms sought, and only C. perfringens counts were correlated with human enteric viruses, cysts, or oocysts. For settled and filtered water samples, all indicators were statistically correlated with human enteric viruses but not with cysts or oocysts. By using multiple regression, the somatic coliphage counts were the only explanatory variable for the human enteric virus counts in settled water, while in filtered water samples it was C. perfringens counts. Finished water samples of 1,000 liters each were free of all microorganisms, except for a single sample that contained low levels of cysts and oocysts of undetermined viability. Three of nine finished water samples of 20,000 liters each revealed residual levels of somatic coliphages at 0.03, 0.10, and 0.26 per 100 liters. Measured virus removal was more than 4 to 5 log10, and cyst removal was more than 4 log10. Coliphage and C. perfringens counts suggested that the total removal and inactivation was more than 7 log10 viable microorganisms. C. perfringens counts appear to be the most suitable indicator for the inactivation and removal of viruses in drinking water treatment.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8368831

A microfluidic biochip for complete blood cell counts at the point-of-care

PubMed Central

Hassan, U.; Reddy, B.; Damhorst, G.; Sonoiki, O.; Ghonge, T.; Yang, C.; Bashir, R.

2016-01-01

Complete blood cell counts (CBCs) are one of the most commonly ordered and informative blood tests in hospitals. The results from a CBC, which typically include white blood cell (WBC) counts with differentials, red blood cell (RBC) counts, platelet counts and hemoglobin measurements, can have implications for the diagnosis and screening of hundreds of diseases and treatments. Bulky and expensive hematology analyzers are currently used as a gold standard for acquiring CBCs. For nearly all CBCs performed today, the patient must travel to either a hospital with a large laboratory or to a centralized lab testing facility. There is a tremendous need for an automated, portable point-of-care blood cell counter that could yield results in a matter of minutes from a drop of blood without any trained professionals to operate the instrument. We have developed microfluidic biochips capable of a partial CBC using only a drop of whole blood. Total leukocyte and their 3-part differential count are obtained from 10 μL of blood after on-chip lysing of the RBCs and counting of the leukocytes electrically using microfabricated platinum electrodes. For RBCs and platelets, 1 μL of whole blood is diluted with PBS on-chip and the cells are counted electrically. The total time for measurement is under 20 minutes. We demonstrate a high correlation of blood cell counts compared to results acquired with a commercial hematology analyzer. This technology could potentially have tremendous applications in hospitals at the bedside, private clinics, retail clinics and the developing world. PMID:26909365

A microfluidic biochip for complete blood cell counts at the point-of-care.

PubMed

Hassan, U; Reddy, B; Damhorst, G; Sonoiki, O; Ghonge, T; Yang, C; Bashir, R

2015-12-01

Complete blood cell counts (CBCs) are one of the most commonly ordered and informative blood tests in hospitals. The results from a CBC, which typically include white blood cell (WBC) counts with differentials, red blood cell (RBC) counts, platelet counts and hemoglobin measurements, can have implications for the diagnosis and screening of hundreds of diseases and treatments. Bulky and expensive hematology analyzers are currently used as a gold standard for acquiring CBCs. For nearly all CBCs performed today, the patient must travel to either a hospital with a large laboratory or to a centralized lab testing facility. There is a tremendous need for an automated, portable point-of-care blood cell counter that could yield results in a matter of minutes from a drop of blood without any trained professionals to operate the instrument. We have developed microfluidic biochips capable of a partial CBC using only a drop of whole blood. Total leukocyte and their 3-part differential count are obtained from 10 μL of blood after on-chip lysing of the RBCs and counting of the leukocytes electrically using microfabricated platinum electrodes. For RBCs and platelets, 1 μL of whole blood is diluted with PBS on-chip and the cells are counted electrically. The total time for measurement is under 20 minutes. We demonstrate a high correlation of blood cell counts compared to results acquired with a commercial hematology analyzer. This technology could potentially have tremendous applications in hospitals at the bedside, private clinics, retail clinics and the developing world.

Assessment of Blood Collection from the Lateral Saphenous Vein for Microfilaria Counts in Mongolian Gerbils (Meriones unguiculatus) Infected with Brugia pahangi

PubMed Central

Alworth, Leanne C; Berghaus, Roy D; Kelly, Lisa M; Supakorndej, Prasit; Burkman, Erica J; Savadelis, Molly D; Cooper, Tanya L; Salyards, Gregory W; Harvey, Stephen B; Moorhead, Andrew R

2015-01-01

The NIH guidelines for survival bleeding of mice and rats note that using the retroorbital plexus has a greater potential for complications than do other methods of blood collection and that this procedure should be performed on anesthetized animals. Lateral saphenous vein puncture has a low potential for complications and can be performed without anesthesia. Mongolian gerbils (Meriones unguiculatus) are the preferred rodent model for filarial parasite research. To monitor microfilaria counts in the blood, blood sampling from the orbital plexus has been the standard. Our goal was to refine the blood collection technique. To determine whether blood collection from the lateral saphenous vein was a feasible alternative to retroorbital sampling, we compared microfilaria counts in blood samples collected by both methods from 21 gerbils infected with the filarial parasitic worm Brugia pahangi. Lateral saphenous vein counts were equivalent to retroorbital counts at relatively high counts (greater than 50 microfilariae per 20 µL) but were significantly lower than retroorbital counts when microfilarial concentrations were lower. Our results indicate that although retroorbital collection may be preferable when low concentrations of microfilariae need to be enumerated, the lateral saphenous vein is a suitable alternative site for blood sampling to determine microfilaremia and is a feasible refinement that can benefit the wellbeing of gerbils. PMID:26678366

Methods for assessing long-term mean pathogen count in drinking water and risk management implications.

PubMed

Englehardt, James D; Ashbolt, Nicholas J; Loewenstine, Chad; Gadzinski, Erik R; Ayenu-Prah, Albert Y

2012-06-01

Recently pathogen counts in drinking and source waters were shown theoretically to have the discrete Weibull (DW) or closely related discrete growth distribution (DGD). The result was demonstrated versus nine short-term and three simulated long-term water quality datasets. These distributions are highly skewed such that available datasets seldom represent the rare but important high-count events, making estimation of the long-term mean difficult. In the current work the methods, and data record length, required to assess long-term mean microbial count were evaluated by simulation of representative DW and DGD waterborne pathogen count distributions. Also, microbial count data were analyzed spectrally for correlation and cycles. In general, longer data records were required for more highly skewed distributions, conceptually associated with more highly treated water. In particular, 500-1,000 random samples were required for reliable assessment of the population mean ±10%, though 50-100 samples produced an estimate within one log (45%) below. A simple correlated first order model was shown to produce count series with 1/f signal, and such periodicity over many scales was shown in empirical microbial count data, for consideration in sampling. A tiered management strategy is recommended, including a plan for rapid response to unusual levels of routinely-monitored water quality indicators.

Accelerated high-resolution photoacoustic tomography via compressed sensing

NASA Astrophysics Data System (ADS)

Arridge, Simon; Beard, Paul; Betcke, Marta; Cox, Ben; Huynh, Nam; Lucka, Felix; Ogunlade, Olumide; Zhang, Edward

2016-12-01

Current 3D photoacoustic tomography (PAT) systems offer either high image quality or high frame rates but are not able to deliver high spatial and temporal resolution simultaneously, which limits their ability to image dynamic processes in living tissue (4D PAT). A particular example is the planar Fabry-Pérot (FP) photoacoustic scanner, which yields high-resolution 3D images but takes several minutes to sequentially map the incident photoacoustic field on the 2D sensor plane, point-by-point. However, as the spatio-temporal complexity of many absorbing tissue structures is rather low, the data recorded in such a conventional, regularly sampled fashion is often highly redundant. We demonstrate that combining model-based, variational image reconstruction methods using spatial sparsity constraints with the development of novel PAT acquisition systems capable of sub-sampling the acoustic wave field can dramatically increase the acquisition speed while maintaining a good spatial resolution: first, we describe and model two general spatial sub-sampling schemes. Then, we discuss how to implement them using the FP interferometer and demonstrate the potential of these novel compressed sensing PAT devices through simulated data from a realistic numerical phantom and through measured data from a dynamic experimental phantom as well as from in vivo experiments. Our results show that images with good spatial resolution and contrast can be obtained from highly sub-sampled PAT data if variational image reconstruction techniques that describe the tissues structures with suitable sparsity-constraints are used. In particular, we examine the use of total variation (TV) regularization enhanced by Bregman iterations. These novel reconstruction strategies offer new opportunities to dramatically increase the acquisition speed of photoacoustic scanners that employ point-by-point sequential scanning as well as reducing the channel count of parallelized schemes that use detector arrays.

Statistical analysis of environmental monitoring data: does a worst case time for monitoring clean rooms exist?

PubMed

Cundell, A M; Bean, R; Massimore, L; Maier, C

1998-01-01

To determine the relationship between the sampling time of the environmental monitoring, i.e., viable counts, in aseptic filling areas and the microbial count and frequency of alerts for air, surface and personnel microbial monitoring, statistical analyses were conducted on 1) the frequency of alerts versus the time of day for routine environmental sampling conducted in calendar year 1994, and 2) environmental monitoring data collected at 30-minute intervals during routine aseptic filling operations over two separate days in four different clean rooms with multiple shifts and equipment set-ups at a parenteral manufacturing facility. Statistical analyses showed, except for one floor location that had significantly higher number of counts but no alert or action level samplings in the first two hours of operation, there was no relationship between the number of counts and the time of sampling. Further studies over a 30-day period at the floor location showed no relationship between time of sampling and microbial counts. The conclusion reached in the study was that there is no worst case time for environmental monitoring at that facility and that sampling any time during the aseptic filling operation will give a satisfactory measure of the microbial cleanliness in the clean room during the set-up and aseptic filling operation.

Analysis of moisture content, acidity and contamination by yeast and molds in Apis mellifera L. honey from central Brazil

PubMed Central

Ananias, Karla Rubia; de Melo, Adriane Alexandre Machado; de Moura, Celso José

2013-01-01

The development of mold of environmental origin in honey affects its quality and leads to its deterioration, so yeasts and molds counts have been used as an important indicator of hygiene levels during its processing, transportation and storage. The aim of this study was to evaluate the levels of yeasts and molds contamination and their correlation with moisture and acidity levels in Apis mellifera L. honey from central Brazil. In 20% of the samples, the yeasts and molds counts exceeded the limit established by legislation for the marketing of honey in the MERCOSUR, while 42.8% and 5.7% presented above-standard acidity and moisture levels, respectively. Although samples showed yeasts and molds counts over 1.0 × 102 UFC.g−1, there was no correlation between moisture content and the number of microorganisms, since, in part of the samples with above-standard counts, the moisture level was below 20%. In some samples the acidity level was higher than that established by legislation, but only one sample presented a yeasts and molds count above the limit established by MERCOSUR, which would suggest the influence of the floral source on this parameter. In general, of the 35 samples analyzed, the quality was considered inadequate in 45.7% of cases. PMID:24516434

The relationship between flesh quality and numbers of Kudoa thyrsites plasmodia and spores in farmed Atlantic salmon, Salmo salar L.

PubMed

Dawson-Coates, J A; Chase, J C; Funk, V; Booy, M H; Haines, L R; Falkenberg, C L; Whitaker, D J; Olafson, R W; Pearson, T W

2003-08-01

Atlantic salmon, Salmo salar L., were exposed to Kudoa thyrsites (Myxozoa, Myxosporea)-containing sea water for 15 months, and then harvested and assessed for parasite burden and fillet quality. At harvest, parasites were enumerated in muscle samples from a variety of somatic and opercular sites, and mean counts were determined for each fish. After 6 days storage at 4 degrees C, fillet quality was determined by visual assessment and by analysis of muscle firmness using a texture analyzer. Fillet quality could best be predicted by determining mean parasite numbers and spore counts in all eight tissue samples (somatic and opercular) or in four fillet samples, as the counts from opercular samples alone showed greater variability and thus decreased reliability. The variability in both plasmodia and spore numbers between tissue samples taken from an individual fish indicated that the parasites were not uniformly distributed in the somatic musculature. Therefore, to best predict the probable level of fillet degradation caused by K. thyrsites infections, multiple samples must be taken from each fish. If this is performed, a mean plasmodia count of 0.3 mm(-2) or a mean spore count of 4.0 x 10(5) g(-1) of tissue are the levels where the probability of severe myoliquefaction becomes a significant risk.

Analysis of moisture content, acidity and contamination by yeast and molds in Apis mellifera L. honey from central Brazil.

PubMed

Ananias, Karla Rubia; de Melo, Adriane Alexandre Machado; de Moura, Celso José

2013-01-01

The development of mold of environmental origin in honey affects its quality and leads to its deterioration, so yeasts and molds counts have been used as an important indicator of hygiene levels during its processing, transportation and storage. The aim of this study was to evaluate the levels of yeasts and molds contamination and their correlation with moisture and acidity levels in Apis mellifera L. honey from central Brazil. In 20% of the samples, the yeasts and molds counts exceeded the limit established by legislation for the marketing of honey in the MERCOSUR, while 42.8% and 5.7% presented above-standard acidity and moisture levels, respectively. Although samples showed yeasts and molds counts over 1.0 × 10(2) UFC.g(-1), there was no correlation between moisture content and the number of microorganisms, since, in part of the samples with above-standard counts, the moisture level was below 20%. In some samples the acidity level was higher than that established by legislation, but only one sample presented a yeasts and molds count above the limit established by MERCOSUR, which would suggest the influence of the floral source on this parameter. In general, of the 35 samples analyzed, the quality was considered inadequate in 45.7% of cases.

Bacterial and fungal microbiota of spontaneously fermented Chinese products, Rubing milk cake and Yan-cai vegetable pickles.

PubMed

Liu, Xin; Kuda, Takashi; Takahashi, Hajime; Kimura, Bon

2018-06-01

The Rubing milk cake from Yunnan and the Yan-cai vegetable pickles from Guangdong are traditional spontaneously fermented foods in China. We evaluated the microbial properties of these products with the analysis of their bacterial and fungal microbiota using classical culture-dependent and culture-independent methods, including a 16S rDNA gene (V4) and an internal transcribed spacer (ITS) region pyrosequencing method with MiSeq system. The viable lactic acid bacteria (LAB) count was 8 and 6 log colony-forming units (CFU)/g in Rubing and Yan-cai samples, respectively. The yeast count was approximately 100-1000 times less than the LAB count in most samples, except one Yan-cai sample. In addition, the gram-negative rod count in half of the samples was similar to the LAB count. Pyrosequencing results revealed the high abundance (10%-20%) of gram-negative Pseudomonas spp. and Enterobacteriaceae in these samples. These results suggest that some of these traditional foods are undesirable as ready-to-eat (RTE) foods, even when these are typical lactic acid fermented foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

Relationship between automated total nucleated cell count and enumeration of cells on direct smears of canine synovial fluid.

PubMed

Dusick, Allison; Young, Karen M; Muir, Peter

2014-12-01

Canine osteoarthritis is a common disorder seen in veterinary clinical practice and causes considerable morbidity in dogs as they age. Synovial fluid analysis is an important tool for diagnosis and treatment of canine joint disease and obtaining a total nucleated cell count (TNCC) is particularly important. However, the low sample volumes obtained during arthrocentesis are often insufficient for performing an automated TNCC, thereby limiting diagnostic interpretation. The aim of the present study was to investigate whether estimation of TNCC in canine synovial fluid could be achieved by performing manual cell counts on direct smears of fluid. Fifty-eight synovial fluid samples, taken by arthrocentesis from 48 dogs, were included in the study. Direct smears of synovial fluid were prepared, and hyaluronidase added before cell counts were obtained using a commercial laser-based instrument. A protocol was established to count nucleated cells in a specific region of the smear, using a serpentine counting pattern; the mean number of nucleated cells per 400 × field was then calculated. There was a positive correlation between the automated TNCC and mean manual cell count, with more variability at higher TNCC. Regression analysis was performed to estimate TNCC from manual counts. By this method, 78% of the samples were correctly predicted to fall into one of three categories (within the reference interval, mildly to moderately increased, or markedly increased) relative to the automated TNCC. Intra-observer and inter-observer agreement was good to excellent. The results of the study suggest that interpretation of canine synovial fluid samples of low volume can be aided by methodical manual counting of cells on direct smears. Copyright © 2014 Elsevier Ltd. All rights reserved.

Total nucleated cell and leukocyte differential counts in canine pleural and peritoneal fluid and equine synovial fluid samples: comparison of automated and manual methods.

PubMed

Brudvig, Jean M; Swenson, Cheryl L

2015-12-01

Rapid and precise measurement of total and differential nucleated cell counts is a crucial diagnostic component of cavitary and synovial fluid analyses. The objectives of this study included (1) evaluation of reliability and precision of canine and equine fluid total nucleated cell count (TNCC) determined by the benchtop Abaxis VetScan HM5, in comparison with the automated reference instruments ADVIA 120 and the scil Vet abc, respectively, and (2) comparison of automated with manual canine differential nucleated cell counts. The TNCC and differential counts in canine pleural and peritoneal, and equine synovial fluids were determined on the Abaxis VetScan HM5 and compared with the ADVIA 120 and Vet abc analyzer, respectively. Statistical analyses included correlation, least squares fit linear regression, Passing-Bablok regression, and Bland-Altman difference plots. In addition, precision of the total cell count generated by the VetScan HM5 was determined. Agreement was excellent without significant constant or proportional bias for canine cavitary fluid TNCC. Automated and manual differential counts had R(2)  < .5 for individual cell types (least squares fit linear regression). Equine synovial fluid TNCC agreed but with some bias due to the VetScan HM5 overestimating TNCC compared to the Vet abc. Intra-assay precision of the VetScan HM5 in 3 fluid samples was 2-31%. The Abaxis VetScan HM5 provided rapid, reliable TNCC for canine and equine fluid samples. The differential nucleated cell count should be verified microscopically as counts from the VetScan HM5 and also from the ADVIA 120 were often incorrect in canine fluid samples. © 2015 American Society for Veterinary Clinical Pathology.

Cross-validation of the Dot Counting Test in a large sample of credible and non-credible patients referred for neuropsychological testing.

PubMed

McCaul, Courtney; Boone, Kyle B; Ermshar, Annette; Cottingham, Maria; Victor, Tara L; Ziegler, Elizabeth; Zeller, Michelle A; Wright, Matthew

2018-01-18

To cross-validate the Dot Counting Test in a large neuropsychological sample. Dot Counting Test scores were compared in credible (n = 142) and non-credible (n = 335) neuropsychology referrals. Non-credible patients scored significantly higher than credible patients on all Dot Counting Test scores. While the original E-score cut-off of ≥17 achieved excellent specificity (96.5%), it was associated with mediocre sensitivity (52.8%). However, the cut-off could be substantially lowered to ≥13.80, while still maintaining adequate specificity (≥90%), and raising sensitivity to 70.0%. Examination of non-credible subgroups revealed that Dot Counting Test sensitivity in feigned mild traumatic brain injury (mTBI) was 55.8%, whereas sensitivity was 90.6% in patients with non-credible cognitive dysfunction in the context of claimed psychosis, and 81.0% in patients with non-credible cognitive performance in depression or severe TBI. Thus, the Dot Counting Test may have a particular role in detection of non-credible cognitive symptoms in claimed psychiatric disorders. Alternative to use of the E-score, failure on ≥1 cut-offs applied to individual Dot Counting Test scores (≥6.0″ for mean grouped dot counting time, ≥10.0″ for mean ungrouped dot counting time, and ≥4 errors), occurred in 11.3% of the credible sample, while nearly two-thirds (63.6%) of the non-credible sample failed one of more of these cut-offs. An E-score cut-off of 13.80, or failure on ≥1 individual score cut-offs, resulted in few false positive identifications in credible patients, and achieved high sensitivity (64.0-70.0%), and therefore appear appropriate for use in identifying neurocognitive performance invalidity.

Elders Point East Marsh Island Restoration Monitoring Data Analysis

DTIC Science & Technology

2017-09-21

Figure 13. Average biomass comparison between fertilizer treatment and non- fertilizer treatment at Elders East...25 ERDC/EL CR-17-1 vi Table 5. Count of benthic organisms ...31 Table 6. Benthic Community Indices: True Taxa Richness, Total Organism Count

Outdoor near-roadway, community and residential pollen, carbon dioxide and particulate matter measurements in the urban core of an agricultural region in central CA

NASA Astrophysics Data System (ADS)

Shendell, Derek G.; Therkorn, Jennifer H.; Yamamoto, Naomichi; Meng, Qingyu; Kelly, Sarah W.; Foster, Christine A.

2012-04-01

We can control asthma through proper clinical and environmental management and education. The U.S. population is growing, urbanizing and aging; seniors of low-to-middle income families are working and living longer. We conducted community-based participatory research in Visalia, Tulare County, California with a prospective, cross-sectional repeated measures design and quantitative and qualitative process; home environment and health-related outcomes data were collected. In this paper, we presented results of the air quality sampling-pollen, carbon dioxide (CO2) and particulate matter (PM) outdoors away from most major sources (agricultural fields, large pollinating trees, etc)-at a community central site close to a mobile line source and participant homes in the cooling season, July, 2009. Weather was hot and dry with light winds; diurnal variation ranged between 65-107 °F (18-42 °C) and 12-76% relative humidity at the study's central site. Co-located active (reference) and passive (PAAS) samplers were used for pollen; passive monitoring for CO2 (Telaire 7001) and active sampling for PM were conducted. Overall, we observed spatial variability in CO2, fine PM (PM2.5), and pollen counts. Weekday and study week average CO2 and PM2.5 concentrations were higher near study homes compared to central site sampling points, but peak measures and overnight/pre-dawn time period averages were elevated at the central site. Pollen counts were typically lower at homes-even if grass, trees, flowers or potted plants were present-compared to the central site closer to and generally downwind from commercial agricultural tree production. Data are new; the nine-county San Joaquin Valley has one pollen count station in the national network, and two of four government outdoor air monitoring stations in the county are in national parks. We suggest-given poor air quality in large part due to PM-adding routine pollen counts to regional/state agency air monitoring sites and more CO2 and PM monitoring.

Rapid enumeration of viable bacteria by image analysis

NASA Technical Reports Server (NTRS)

Singh, A.; Pyle, B. H.; McFeters, G. A.

1989-01-01

A direct viable counting method for enumerating viable bacteria was modified and made compatible with image analysis. A comparison was made between viable cell counts determined by the spread plate method and direct viable counts obtained using epifluorescence microscopy either manually or by automatic image analysis. Cultures of Escherichia coli, Salmonella typhimurium, Vibrio cholerae, Yersinia enterocolitica and Pseudomonas aeruginosa were incubated at 35 degrees C in a dilute nutrient medium containing nalidixic acid. Filtered samples were stained for epifluorescence microscopy and analysed manually as well as by image analysis. Cells enlarged after incubation were considered viable. The viable cell counts determined using image analysis were higher than those obtained by either the direct manual count of viable cells or spread plate methods. The volume of sample filtered or the number of cells in the original sample did not influence the efficiency of the method. However, the optimal concentration of nalidixic acid (2.5-20 micrograms ml-1) and length of incubation (4-8 h) varied with the culture tested. The results of this study showed that under optimal conditions, the modification of the direct viable count method in combination with image analysis microscopy provided an efficient and quantitative technique for counting viable bacteria in a short time.

Calibration and comparison of accelerometer cut points in preschool children.

PubMed

van Cauwenberghe, Eveline; Labarque, Valery; Trost, Stewart G; de Bourdeaudhuij, Ilse; Cardon, Greet

2011-06-01

The present study aimed to develop accelerometer cut points to classify physical activities (PA) by intensity in preschoolers and to investigate discrepancies in PA levels when applying various accelerometer cut points. To calibrate the accelerometer, 18 preschoolers (5.8 ± 0.4 years) performed eleven structured activities and one free play session while wearing a GT1M ActiGraph accelerometer using 15 s epochs. The structured activities were chosen based on the direct observation system Children's Activity Rating Scale (CARS) while the criterion measure of PA intensity during free play was provided using a second-by-second observation protocol (modified CARS). Receiver Operating Characteristic (ROC) curve analyses were used to determine the accelerometer cut points. To examine the classification differences, accelerometer data of four consecutive days from 114 preschoolers (5.5 ± 0.3 years) were classified by intensity according to previously published and the newly developed accelerometer cut points. Differences in predicted PA levels were evaluated using repeated measures ANOVA and Chi Square test. Cut points were identified at 373 counts/15 s for light (sensitivity: 86%; specificity: 91%; Area under ROC curve: 0.95), 585 counts/15 s for moderate (87%; 82%; 0.91) and 881 counts/15 s for vigorous PA (88%; 91%; 0.94). Further, applying various accelerometer cut points to the same data resulted in statistically and biologically significant differences in PA. Accelerometer cut points were developed with good discriminatory power for differentiating between PA levels in preschoolers and the choice of accelerometer cut points can result in large discrepancies.

An integrated circuit floating point accumulator

NASA Technical Reports Server (NTRS)

Goldsmith, T. C.

1977-01-01

Goddard Space Flight Center has developed a large scale integrated circuit (type 623) which can perform pulse counting, storage, floating point compression, and serial transmission, using a single monolithic device. Counts of 27 or 19 bits can be converted to transmitted values of 12 or 8 bits respectively. Use of the 623 has resulted in substantial savaings in weight, volume, and dollar resources on at least 11 scientific instruments to be flown on 4 NASA spacecraft. The design, construction, and application of the 623 are described.

Background compensation for a radiation level monitor

DOEpatents

Keefe, D.J.

1975-12-01

Background compensation in a device such as a hand and foot monitor is provided by digital means using a scaler. With no radiation level test initiated, a scaler is down-counted from zero according to the background measured. With a radiation level test initiated, the scaler is up-counted from the previous down-count position according to the radiation emitted from the monitored object and an alarm is generated if, with the scaler having crossed zero in the positive going direction, a particular number is exceeded in a specific time period after initiation of the test. If the test is initiated while the scale is down-counting, the background count from the previous down- count stored in a memory is used as the initial starting point for the up-count.

X-ray Mapping of Terrestrial and Extraterrestrial Materials Using the Electron Microprobe

NASA Technical Reports Server (NTRS)

Carpenter, P.

2006-01-01

Lunar samples returned from the Apollo program motivated development of the Bence-Albee algorithm for the rapid and accurate analysis of lunar materials, and established interlaboratory comparability through its common use. In the analysis of mineral and rock fragments it became necessary to combine micro- and macroscopic analysis by coupling electron-probe microanalysis (EPMA) with automated stage point counting. A coarse grid that included several thousand points was used, and initially wavelength-dispersive (WDS) and later energydispersive (EDS) data were acquired at discrete stage points using approx. 5 sec count times. A approx 50 micrometer beam diameter was used for WDS and up to 500 micrometer beam diameter for EDS analysis. Average analyses of discretely sampled phases were coupled with the point count data to calculate the bulk composition using matrix algebra. Use of a defocused beam resulted in a contribution from multiple phases to each analytical point, and the analytical data were deconvolved relative to end-member phase chemistry on the fly. Impressive agreement was obtained between WDS and EDS measurements as well as comparison with bulk chemistry obtained by other methods. In the 30 years since these methods were developed, significant improvements in EPMA automation and computer processing have taken place. Digital beam control allows routine collection of x-ray maps by EDS, and stage mapping for WDS is conducted continuously at slew speed and incrementally by sampling at discrete points. Digital pulse processing in EDS systems has significantly increased the throughput for EDS mapping, and the ongoing development of Si-drift detector systems promises mapping capabilities rivaling WDS systems. Spectrum imaging allows a data cube of EDS spectra to be acquired and sophisticated processing of the original data is possible using matrix algebra techniques. The study of lunar and meteoritic materials includes the need to conveniently: (1) Characterize the sample at microscopic and macroscopic scales with relatively high sensitivity, (2) Determine the modal abundance of minerals, and (3) Identify and relocate discrete features of interest in terms of size and chemistry. The coupled substitution of cations in minerals can result in significant variation in mineral chemistry, but at similar average Z, leading to poor backscattered-electron (BSE) contrast discrimination of mineralogy. It is necessary to discriminate phase chemistry at both the trace element level and the major element level. To date, the WDS of microprobe systems is preferred for mapping due to high throughput and the ability to obtain the necessary intensity to discriminate phases at both trace and major element concentrations. It is desirable to produce fully quantitative compositional maps of geological materials, which requires the acquisition of k-ratio maps that are background and dead-time corrected, and which have been corrected by phi(delta z> or an equivalent algorithm at each pixel. To date, turnkey systems do not allow the acquisition of k-ratio maps and the rigorous correction in this manner. X-ray maps of a chondrule from the Ourique meteorite, and a comb-layered xenolith from the San Francisco volcanic field, have been analyzed and processed to extract phase information. The Ourique meteorite presents a challenge due to relatively low BSE contrast, and has been studied using spectrum imaging. X-ray maps for Si, Mg, and FeK(alpha) were used to produce RGB images. The xenolith sample contains sector-zoned augite, olivine, plagioclase, and basaltic glass. X-ray maps were processed using Lispix and ImageJ software to produce mineral phase maps. The x-ray maps for Mg, Ca, and Ti were used with traceback to generate binary images that were converted to RGB images. These approaches are successful in discriminating phases, but it is desirable to achieve the methods that were used on lunar samples 30 years ago on current microprobe systems. Curnt research includes x-ray mapping analysis of the Dalgety Downs chondrite by micro x-ray fluorescence and spectrum imaging, in collaboration with Kenny Witherspoon of IXRF Systems and Dale Newbury of NIST.

Cosmic ray intensity gradients in the solar system

NASA Technical Reports Server (NTRS)

Mckibben, R. B.

1975-01-01

Recent progress in the determination of cosmic-ray intensity gradients is reviewed. Direct satellite measurements of the integral gradient are described together with various types of indirect measurements, including measurements of the Ar-37/Ar-39 ratio in samples from the Lost City meteorite, studies of anisotropies in neutron-monitor counting rates, and analysis of the sidereal diurnal anisotropy observed at a single point on earth. Nucleonic radial gradients and electron gradients measured by satellites in differential energy windows are discussed, and theoretical studies of the physical processes involved in these gradients are summarized. Observations of intensity gradients in heliographic latitude are reported.

FPGA based demodulation of laser induced fluorescence in plasmas

NASA Astrophysics Data System (ADS)

Mattingly, Sean W.; Skiff, Fred

2018-04-01

We present a field programmable gate array (FPGA)-based system that counts photons from laser-induced fluorescence (LIF) on a laboratory plasma. This is accomplished with FPGA-based up/down counters that demodulate the data, giving a background-subtracted LIF signal stream that is updated with a new point as each laser amplitude modulation cycle completes. We demonstrate using the FPGA to modulate a laser at 1 MHz and demodulate the resulting LIF data stream. This data stream is used to calculate an LIF-based measurement sampled at 1 MHz of a plasma ion fluctuation spectrum.

Using a Mobile Device “App” and Proximal Remote Sensing Technologies to Assess Soil Cover Fractions on Agricultural Fields

PubMed Central

Laamrani, Ahmed; Branson, Dave; Joosse, Pamela

2018-01-01

Quantifying the amount of crop residue left in the field after harvest is a key issue for sustainability. Conventional assessment approaches (e.g., line-transect) are labor intensive, time-consuming and costly. Many proximal remote sensing devices and systems have been developed for agricultural applications such as cover crop and residue mapping. For instance, current mobile devices (smartphones & tablets) are usually equipped with digital cameras and global positioning systems and use applications (apps) for in-field data collection and analysis. In this study, we assess the feasibility and strength of a mobile device app developed to estimate crop residue cover. The performance of this novel technique (from here on referred to as “app” method) was compared against two point counting approaches: an established digital photograph-grid method and a new automated residue counting script developed in MATLAB at the University of Guelph. Both photograph-grid and script methods were used to count residue under 100 grid points. Residue percent cover was estimated using the app, script and photograph-grid methods on 54 vertical digital photographs (images of the ground taken from above at a height of 1.5 m) collected from eighteen fields (9 corn and 9 soybean, 3 samples each) located in southern Ontario. Results showed that residue estimates from the app method were in good agreement with those obtained from both photograph–grid and script methods (R2 = 0.86 and 0.84, respectively). This study has found that the app underestimates the residue coverage by −6.3% and −10.8% when compared to the photograph-grid and script methods, respectively. With regards to residue type, soybean has a slightly lower bias than corn (i.e., −5.3% vs. −7.4%). For photos with residue <30%, the app derived residue measurements are within ±5% difference (bias) of both photograph-grid- and script-derived residue measurements. These methods could therefore be used to track the recommended minimum soil residue cover of 30%, implemented to reduce farmland topsoil and nutrient losses that impact water quality. Overall, the app method was found to be a good alternative to the point counting methods, which are more time-consuming. PMID:29495497

A Five-Year Longitudinal Analysis of Sooty Mangabeys Naturally Infected with Simian Immunodeficiency Virus Reveals a Slow but Progressive Decline in CD4+ T-Cell Count Whose Magnitude Is Not Predicted by Viral Load or Immune Activation▿

PubMed Central

Taaffe, Jessica; Chahroudi, Ann; Engram, Jessica; Sumpter, Beth; Meeker, Tracy; Ratcliffe, Sarah; Paiardini, Mirko; Else, James; Silvestri, Guido

2010-01-01

Natural simian immunodeficiency virus (SIV) infection in sooty mangabeys (SMs) typically does not result in AIDS, despite high-level viremia and significant depletion of mucosal CD4+ T cells. Here, we report the results of the first longitudinal study of a large cohort of SMs naturally infected with SIV (n = 78) housed at the Yerkes National Primate Research Center from which samples were obtained three times over a 5-year period. In this study, we observed (i) no signs of simian AIDS, (ii) stable SIV loads, (iii) a slow but progressive decline in CD4+ T-cell counts (from a mean of 1,067.0 cells/mm3 at time point 1 to 764.8 cells/mm3 at time point 3) and increases in the numbers of animals with CD4+ T-cell levels below 500 and 200 cells/mm3 (from 8 to 28 of 78 and from 1 to 4 of 78, respectively), (iv) progressive declines in percentages of naïve CD4+ and CD8+ T cells (from 37.7 to 24.8% and from 21.0 to 13.0%, respectively), and (v) stably low levels of activated/proliferating T cells as well as CD4+ CCR5+ T cells. Since the level of total CD4+ T cells and the fraction of naïve T cells in SIV-uninfected SMs also declined, it is possible that some of these observations are related to aging, as the SIV-infected animals were significantly older than the uninfected animals. In contrast to the decline in CD4+ T cell counts in individuals infected with human immunodeficiency virus (HIV), the decline in CD4+ T cell counts in SMs naturally infected with SIV over a 5-year period was not predicted by either plasma viremia or levels of T-cell activation. Taken together, these results confirm that natural SIV infection is nonprogressive from a clinical, virological, and immunological point of view and that stable levels of viremia associated with persistently low-level immune activation represent key differences from the natural course of HIV infection in humans. PMID:20335252

A five-year longitudinal analysis of sooty mangabeys naturally infected with simian immunodeficiency virus reveals a slow but progressive decline in CD4+ T-cell count whose magnitude is not predicted by viral load or immune activation.

PubMed

Taaffe, Jessica; Chahroudi, Ann; Engram, Jessica; Sumpter, Beth; Meeker, Tracy; Ratcliffe, Sarah; Paiardini, Mirko; Else, James; Silvestri, Guido

2010-06-01

Natural simian immunodeficiency virus (SIV) infection in sooty mangabeys (SMs) typically does not result in AIDS, despite high-level viremia and significant depletion of mucosal CD4(+) T cells. Here, we report the results of the first longitudinal study of a large cohort of SMs naturally infected with SIV (n = 78) housed at the Yerkes National Primate Research Center from which samples were obtained three times over a 5-year period. In this study, we observed (i) no signs of simian AIDS, (ii) stable SIV loads, (iii) a slow but progressive decline in CD4(+) T-cell counts (from a mean of 1,067.0 cells/mm(3) at time point 1 to 764.8 cells/mm(3) at time point 3) and increases in the numbers of animals with CD4(+) T-cell levels below 500 and 200 cells/mm(3) (from 8 to 28 of 78 and from 1 to 4 of 78, respectively), (iv) progressive declines in percentages of naïve CD4(+) and CD8(+) T cells (from 37.7 to 24.8% and from 21.0 to 13.0%, respectively), and (v) stably low levels of activated/proliferating T cells as well as CD4(+) CCR5(+) T cells. Since the level of total CD4(+) T cells and the fraction of naïve T cells in SIV-uninfected SMs also declined, it is possible that some of these observations are related to aging, as the SIV-infected animals were significantly older than the uninfected animals. In contrast to the decline in CD4(+) T cell counts in individuals infected with human immunodeficiency virus (HIV), the decline in CD4(+) T cell counts in SMs naturally infected with SIV over a 5-year period was not predicted by either plasma viremia or levels of T-cell activation. Taken together, these results confirm that natural SIV infection is nonprogressive from a clinical, virological, and immunological point of view and that stable levels of viremia associated with persistently low-level immune activation represent key differences from the natural course of HIV infection in humans.

[Possibility of cauda equina nerve root damage from lumbar punctures performed with 25-gauge Quincke and Whitacre needles].

PubMed

Reina, M A; López, A; Villanueva, M C; De Andrés, J A; Martín, S

2005-05-01

To assess the possibility of puncturing nerve roots in the cauda equina with spinal needles with different point designs and to quantify the number of axons affected. We performed in vitro punctures of human nerve roots taken from 3 fresh cadavers. Twenty punctures were performed with 25-gauge Whitacre needles and 40 with 25-gauge Quincke needles; half the Quincke needle punctures were carried out with the point perpendicular to the root and the other half with the point parallel to it. The samples were studied by optical and scanning electron microscopy. The possibility of finding the needle orifece inserted inside the nerve was assessed. On a photographic montage, we counted the number of axons during a hypothetical nerve puncture. Nerve roots used in this study were between 1 and 2.3 mm thick, allowing the needle to penetrate the root in the 52 samples studied. The needle orifice was never fully located inside the nerve in any of the samples. The numbers of myelinized axons affected during nerve punctures 0.2 mm deep were 95, 154, and 81 for Whitacre needles, Quincke needles with the point held perpendicular, or the same needle type held parallel, respectively. During punctures 0.5 mm deep, 472, 602, and 279 were affected for each puncture group, respectively. The differences in all cases were statistically significant. It is possible to achieve intraneural puncture with 25-gauge needles. However, full intraneural placement of the orifice of the needle is unlikely. In case of nerve trauma, the damage could be greater if puncture is carried out with a Quincke needle with the point inserted perpendicular to the nerve root.

Quality and shelf life evaluation of fermented sausages of buffalo meat with different levels of heart and fat.

PubMed

Ahmad, S; Srivastava, P K

2007-04-01

Investigations were carried to study the effect of heart incorporation (0%, 15% and 20%) and increasing levels of fat (20% and 25%) on physicochemical (pH, moisture content and thiobarbituric acid, TBA number) and microbiological (total plate count and yeast and mold count) quality and shelf life of semi dry sausages of buffalo meat during refrigerated storage (4°C). Different levels of fat significantly (p<0.05) increased the pH of the sausage samples. However different levels of heart incorporation did not significantly (p<0.05) affect pH, moisture content and TBA number of sausage samples. Fresh samples had pH, moisture content and TBA number in the range of 5.15-5.28, 42.4-47.4% and 0.073-0.134 respectively. Refrigerated storage significantly (p<0.05) increased TBA number of control samples while storage did not significantly (p<0.05) increase the TBA number of sodium ascorbate (SA) treated samples. Total plate counts of twelve sausage samples were f under the TFTC (too few to count) limit at the initial stage. Incorporation of different levels of heart and also increasing levels of fat did not significantly (p<0.05) increase the log TPC/g values. Yeast and molds were not detected in twelve samples of semi dry fermented sausages in their fresh condition. Storage revealed that there was a consistent decrease in pH, and moisture content. Refrigerated storage significantly (p<0.05) reduced both pH and moisture contents. TBA number and total plate counts and yeast and mold counts of controls were found to increase significantly (p<0.05) during refrigerated storage. However, in SA treated sausage, only TPC and yeast and mold count significantly (p<0.05) increased during refrigerated storage. Shelf life of the sausages was found to be 60 days under refrigerated storage (4°C).

Development of binomial sequential sampling plans for forecasting Listronotus maculicollis (Coleoptera: Curculionidae) larvae based on the relationship to adult counts and turfgrass damage.

PubMed

McGraw, Benjamin A; Koppenhöfer, Albrecht M

2009-06-01

Binomial sequential sampling plans were developed to forecast weevil Listronotus maculicollis Kirby (Coleoptera: Curculionidae), larval damage to golf course turfgrass and aid in the development of integrated pest management programs for the weevil. Populations of emerging overwintered adults were sampled over a 2-yr period to determine the relationship between adult counts, larval density, and turfgrass damage. Larval density and composition of preferred host plants (Poa annua L.) significantly affected the expression of turfgrass damage. Multiple regression indicates that damage may occur in moderately mixed P. annua stands with as few as 10 larvae per 0.09 m2. However, > 150 larvae were required before damage became apparent in pure Agrostis stolonifera L. plots. Adult counts during peaks in emergence as well as cumulative counts across the emergence period were significantly correlated to future densities of larvae. Eight binomial sequential sampling plans based on two tally thresholds for classifying infestation (T = 1 and two adults) and four adult density thresholds (0.5, 0.85, 1.15, and 1.35 per 3.34 m2) were developed to forecast the likelihood of turfgrass damage by using adult counts during peak emergence. Resampling for validation of sample plans software was used to validate sampling plans with field-collected data sets. All sampling plans were found to deliver accurate classifications (correct decisions were made between 84.4 and 96.8%) in a practical timeframe (average sampling cost < 22.7 min).

Microbiological Findings in Ready-to-Eat and Precooked Food Distributed in Public Catering Halls in Cagliari Province, Italy.

PubMed

Brignardello, Silvana; Sabiu, Rosangela; Tedde, Tiziana; Cocco, Enrica; Pitzalis, Gabriella; Meli, Clara; Cogoni, Maria Paola

2014-08-28

During this research 159 samples of ready-to-eat and precooked food were examined for the detection of Salmonella spp., Listeria monocytogenes , Escherichia coli , coagulase-positive staphylococci and Enterobacteriaceae , bacterial count. All samples were negative for Salmonella spp. and Listeria monocytogenes ; although a low count of coagulase-positive staphylococci (no. 5 samples) and E. coli (no. 3) was found. We proceeded with the identification of the isolates on every sample with high, moderate and low-count of Enterobacteriaceae , to better understand the microbial ecology. The Enterobacteriaceae species most frequently detected were Pantoea spp. (29.62%), Enterobacter cloacae (20.37%) and Serratia liquefaciens (12.96%); other different species of Enterobacteriaceae were detected with a <10% presence. Since there are no legal regulations indicating tolerance or limit values or this kind of microorganisms related to the samples, it would be appropriate, in the presence of high count of Enterobacteriaceae or by type of ready-to-eat and precooked food, to proceed with the identification of every microorganism.

Fluorometric determination of the DNA concentration in municipal drinking water.

PubMed Central

McCoy, W F; Olson, B H

1985-01-01

DNA concentrations in municipal drinking water samples were measured by fluorometry, using Hoechst 33258 fluorochrome. The concentration, extraction, and detection methods used were adapted from existing techniques. The method is reproducible, fast, accurate, and simple. The amounts of DNA per cell for five different bacterial isolates obtained from drinking water samples were determined by measuring DNA concentration and total cell concentration (acridine orange epifluorescence direct cell counting) in stationary pure cultures. The relationship between DNA concentration and epifluorescence total direct cell concentration in 11 different drinking water samples was linear and positive; the amounts of DNA per cell in these samples did not differ significantly from the amounts in pure culture isolates. We found significant linear correlations between DNA concentration and colony-forming unit concentration, as well as between epifluorescence direct cell counts and colony-forming unit concentration. DNA concentration measurements of municipal drinking water samples appear to monitor changes in bacteriological quality at least as well as total heterotrophic plate counting and epifluorescence direct cell counting. PMID:3890737

Detection of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa)

NASA Astrophysics Data System (ADS)

Ekawati, ER; Yusmiati, S. N. H.

2018-01-01

Blood cockle (Anadara granosa) has high level of zinc and protein, which is beneficial for therapeutic function for malnourished particularly stunting case in children. Zinc in animal foods is more absorbable than that from vegetable food. Blood cockle (Anadara granosa) is rich in nutrient and an excellent environment for the growth of microorganisms. This research aimed to identify the contamination of Salmonella sp., Vibrio sp. and total plate count bacteria on blood cockle (Anadara granosa). This was observation research with laboratory analysis. Salmonella sp. and Vibrio sp. were detected from blood cockle. Total plate count was determine of the total amount of the bacteria. Results detected from 20 samples of blood cockle showed that all samples were negative of Salmonella sp. and 1 sample positive Vibrio sp. The result of total plate count bacteria was < 5 x 105 colony/g sample.

Effect of sodium alginate coating incorporated with nisin, Cinnamomum zeylanicum, and rosemary essential oils on microbial quality of chicken meat and fate of Listeria monocytogenes during refrigeration.

PubMed

Raeisi, Mojtaba; Tabaraei, Alijan; Hashemi, Mohammad; Behnampour, Nasser

2016-12-05

The present study was conducted to preserve the microbial quality of chicken meat fillets during storage time by using sodium alginate active coating solutions incorporated with different natural antimicrobials including nisin, Cinnamomum zeylanicum (cinnamon), and rosemary essential oils (EOs) which were added individually and in combination. The samples were stored in refrigeration condition for 15days and were analyzed for total viable count, Enterobacteriaceae count, lactic acid bacteria count, Pseudomonas spp. count, psychrotrophic count, and yeast and mold count, as well as fate of inoculated Listeria monocytogenes at 3-day intervals. Results indicated that values of tested microbial indicators in all samples increased during storage. Antimicrobial agents, when used in combination, had stronger effect in preserving the microbial quality of chicken meat samples rather than their individual use and the strongest effect was observed in samples coated with alginate solution containing both cinnamon and rosemary EOs (CEO+REO). However, all treatments significantly inhibited microbial growth when compared to the control (P<0.05). Therefore, based on the results of this study, application of alginate coating solutions containing nisin, cinnamon, and rosemary EOs as natural preservatives is recommended in meat products especially in chicken meats. Copyright © 2016. Published by Elsevier B.V.

Effectiveness of Surface Cleaning and Disinfection in a Brazilian Healthcare Facility.

PubMed

Santos-Junior, Aires G; Ferreira, Adriano M; Frota, Oleci P; Rigotti, Marcelo A; Barcelos, Larissa da S; Lopes de Sousa, Alvaro Francisco; de Andrade, Denise; Guerra, Odanir G; R Furlan, Mara C

2018-01-01

Failures in the processes of cleaning and disinfecting health service surfaces may result in the spread and transfer of pathogens that are often associated with healthcare-related infections and outbreaks. To assess the effectiveness of environmental surface cleaning and disinfection in a hospital clinic. The study was conducted in a nursing ward with 45 beds. A total of 80 samples from five high-touch surfaces were evaluated before and after cleaning and disinfection, using the following methods: visual inspection, adenosine triphosphate bioluminescence assay, aerobic colony count, Staphylococcus aureus colony count, and evaluation of resistance to methicillin. The data analysis used nonparametric comparative and correlative tests to observe any differences in the pre- and post- cleaning and disinfection results for the surfaces assessed. Effective cleaning and disinfection had a significant effect on only two surfaces when measured for the presence of adenosine triphosphate, the inner bathroom door handle ( p =0.007) and the toilet bowl ( p =0.01). When evaluated for Staphylococcus aureus colony count, the toilet flush handle also demonstrated a significant effect ( p =0.04). The effectiveness of cleaning and disinfection of the surfaces tested was not satisfactory. An educational intervention is recommended for the cleaning and disinfection staff and the nursing team at the healthcare facility. The data in the study revealed that daily hospital cleaning and disinfection in the sampled sites are not sufficient in medical and surgical wards. Hospital cleanliness must be reevaluated from the point of view of materials, such as an adequate supply of clean cloths, in addition to establishing more precise cleanliness protocols and accurate monitoring systems.

Relationships among bather density, levels of human waterborne pathogens, and fecal coliform counts in marine recreational beach water.

PubMed

Graczyk, Thaddeus K; Sunderland, Deirdre; Awantang, Grace N; Mashinski, Yessika; Lucy, Frances E; Graczyk, Zofi; Chomicz, Lidia; Breysse, Patrick N

2010-04-01

During summer months, samples of marine beach water were tested weekly for human waterborne pathogens in association with high and low bather numbers during weekends and weekdays, respectively. The numbers of bathers on weekends were significantly higher than on weekdays (P < 0.001), and this was associated with a significant (P < 0.04) increase in water turbidity. The proportion of water samples containing Cryptosporidium parvum, Giardia duodenalis, and Enterocytozoon bieneusi was significantly higher (P < 0.03) on weekends than on weekdays, and significantly (P < 0.01) correlated with enterococci counts. The concentration of all three waterborne pathogens was significantly correlated with bather density (P < 0.01). The study demonstrated that: (a) human pathogens were present in beach water on days deemed acceptable for bathing according to fecal bacterial standards; (b) enterococci count was a good indicator for the presence of Cryptosporidium, Giardia, and microsporidian spores in recreational marine beach water; (c) water should be tested for enterococci during times when bather numbers are high; (d) re-suspension of bottom sediments by bathers caused elevated levels of enterococci and waterborne parasites, thus bathers themselves can create a non-point source for water contamination; and (e) exposure to recreational bathing waters can play a role in epidemiology of microsporidiosis. In order to protect public health, it is recommended to: (a) prevent diapered children from entering beach water; (b) introduce bather number limits to recreational areas; (c) advise people with gastroenteritis to avoid bathing; and (d) use showers prior to and after bathing.

Tritium ((3)H) as a tracer for monitoring the dispersion of conservative radionuclides discharged by the Angra dos Reis nuclear power plants in the Piraquara de Fora Bay, Brazil.

PubMed

de Carvalho Gomes, Franciane; Godoy, José Marcus; de Carvalho, Zenildo Lara; de Souza, Elder Magalhães; Rodrigues Silva, José Ivan; Tadeu Lopes, Ricardo

2014-10-01

Presently, two nuclear power plants operate in Brazil. Both are located at Itaorna beach, Angra dos Reis, approximately 133 km from Rio de Janeiro city. The reactor cooling circuits require the input of seawater, which is later discharged through a pipeline into the adjacent Piraquara de Fora Cove. The radioactive effluents undergo ion-exchange treatment prior to their release in batches, causing the enrichment of (3)H relative to other radionuclides in the discharged waters. Under steady state conditions, the (3)H gradient in the Piraquara de Fora waters can be used to determine the dependence of the dilution factor on the distance from the discharge point. The present work describes experiments carried out at the reactor site during batch release episodes, including time series sampling at the discharge point and surface seawater sampling every 250 m to a distance of 1250 m, after a double distillation, the (3)H concentration was measured by liquid scintillation counting applying a Quantulus liquid scintillation spectrometer. The obtained results showed a linear relationship between the (3)H concentration and distance from the discharge point. At 1250 m from the discharge point a dilution index of 1:15 was measured which fits the expected value based on modeling. Copyright © 2014 Elsevier Ltd. All rights reserved.

First oxygen from lunar basalt

NASA Technical Reports Server (NTRS)

Gibson, M. A.; Knudsen, C. W.; Brueneman, D. J.; Kanamori, H.; Ness, R. O.; Sharp, L. L.; Brekke, D. W.; Allen, C. C.; Morris, R. V.; Keller, L. P.

1993-01-01

The Carbotek/Shimizu process to produce oxygen from lunar soils has been successfully demonstrated on actual lunar samples in laboratory facilities at Carbotek with Shimizu funding and support. Apollo sample 70035 containing approximately 25 percent ilmenite (FeTiO3) was used in seven separate reactions with hydrogen varying temperature and pressure: FeTiO3 + H2 yields Fe + TiO2 + H2O. The experiments gave extremely encouraging results as all ilmenite was reduced in every experiment. The lunar ilmenite was found to be about twice as reactive as terrestrial ilmenite samples. Analytical techniques of the lunar and terrestrial ilmenite experiments performed by NASA Johnson Space Center include iron Mossbauer spectroscopy (FeMS), optical microscopy, SEM, TEM, and XRD. The Energy and Environmental Research Center at the University of North Dakota performed three SEM techniques (point count method, morphology determination, elemental mapping), XRD, and optical microscopy.

Bayesian dynamic modeling of time series of dengue disease case counts.

PubMed

Martínez-Bello, Daniel Adyro; López-Quílez, Antonio; Torres-Prieto, Alexander

2017-07-01

The aim of this study is to model the association between weekly time series of dengue case counts and meteorological variables, in a high-incidence city of Colombia, applying Bayesian hierarchical dynamic generalized linear models over the period January 2008 to August 2015. Additionally, we evaluate the model's short-term performance for predicting dengue cases. The methodology shows dynamic Poisson log link models including constant or time-varying coefficients for the meteorological variables. Calendar effects were modeled using constant or first- or second-order random walk time-varying coefficients. The meteorological variables were modeled using constant coefficients and first-order random walk time-varying coefficients. We applied Markov Chain Monte Carlo simulations for parameter estimation, and deviance information criterion statistic (DIC) for model selection. We assessed the short-term predictive performance of the selected final model, at several time points within the study period using the mean absolute percentage error. The results showed the best model including first-order random walk time-varying coefficients for calendar trend and first-order random walk time-varying coefficients for the meteorological variables. Besides the computational challenges, interpreting the results implies a complete analysis of the time series of dengue with respect to the parameter estimates of the meteorological effects. We found small values of the mean absolute percentage errors at one or two weeks out-of-sample predictions for most prediction points, associated with low volatility periods in the dengue counts. We discuss the advantages and limitations of the dynamic Poisson models for studying the association between time series of dengue disease and meteorological variables. The key conclusion of the study is that dynamic Poisson models account for the dynamic nature of the variables involved in the modeling of time series of dengue disease, producing useful models for decision-making in public health.

Automatic sample changer control software for automation of neutron activation analysis process in Malaysian Nuclear Agency

NASA Astrophysics Data System (ADS)

Yussup, N.; Ibrahim, M. M.; Rahman, N. A. A.; Mokhtar, M.; Salim, N. A. A.; Soh@Shaari, S. C.; Azman, A.; Lombigit, L.; Azman, A.; Omar, S. A.

2018-01-01

Most of the procedures in neutron activation analysis (NAA) process that has been established in Malaysian Nuclear Agency (Nuclear Malaysia) since 1980s were performed manually. These manual procedures carried out by the NAA laboratory personnel are time consuming and inefficient especially for sample counting and measurement process. The sample needs to be changed and the measurement software needs to be setup for every one hour counting time. Both of these procedures are performed manually for every sample. Hence, an automatic sample changer system (ASC) that consists of hardware and software is developed to automate sample counting process for up to 30 samples consecutively. This paper describes the ASC control software for NAA process which is designed and developed to control the ASC hardware and call GammaVision software for sample measurement. The software is developed by using National Instrument LabVIEW development package.

Evaluation of mouse red blood cell and platelet counting with an automated hematology analyzer.

PubMed

Fukuda, Teruko; Asou, Eri; Nogi, Kimiko; Goto, Kazuo

2017-10-07

An evaluation of mouse red blood cell (RBC) and platelet (PLT) counting with an automated hematology analyzer was performed with three strains of mice, C57BL/6 (B6), BALB/c (BALB) and DBA/2 (D2). There were no significant differences in RBC and PLT counts between manual and automated optical methods in any of the samples, except for D2 mice. For D2, RBC counts obtained using the manual method were significantly lower than those obtained using the automated optical method (P<0.05), and PLT counts obtained using the manual method were higher than those obtained using the automated optical method (P<0.05). An automated hematology analyzer can be used for RBC and PLT counting; however, an appropriate method should be selected when D2 mice samples are used.

CMOS image sensors as an efficient platform for glucose monitoring.

PubMed

Devadhasan, Jasmine Pramila; Kim, Sanghyo; Choi, Cheol Soo

2013-10-07

Complementary metal oxide semiconductor (CMOS) image sensors have been used previously in the analysis of biological samples. In the present study, a CMOS image sensor was used to monitor the concentration of oxidized mouse plasma glucose (86-322 mg dL(-1)) based on photon count variation. Measurement of the concentration of oxidized glucose was dependent on changes in color intensity; color intensity increased with increasing glucose concentration. The high color density of glucose highly prevented photons from passing through the polydimethylsiloxane (PDMS) chip, which suggests that the photon count was altered by color intensity. Photons were detected by a photodiode in the CMOS image sensor and converted to digital numbers by an analog to digital converter (ADC). Additionally, UV-spectral analysis and time-dependent photon analysis proved the efficiency of the detection system. This simple, effective, and consistent method for glucose measurement shows that CMOS image sensors are efficient devices for monitoring glucose in point-of-care applications.

Combination of Heat Shock and Enhanced Thermal Regime to Control the Growth of a Persistent Legionella pneumophila Strain

PubMed Central

Bédard, Emilie; Boppe, Inès; Kouamé, Serge; Martin, Philippe; Pinsonneault, Linda; Valiquette, Louis; Racine, Jules; Prévost, Michèle

2016-01-01

Following nosocomial cases of Legionella pneumophila, the investigation of a hot water system revealed that 81.5% of sampled taps were positive for L. pneumophila, despite the presence of protective levels of copper in the water. A significant reduction of L. pneumophila counts was observed by culture after heat shock disinfection. The following corrective measures were implemented to control L. pneumophila: increasing the hot water temperature (55 to 60 °C), flushing taps weekly with hot water, removing excess lengths of piping and maintaining a water temperature of 55 °C throughout the system. A gradual reduction in L. pneumophila counts was observed using the culture method and qPCR in the 18 months after implementation of the corrective measures. However, low level contamination was retained in areas with hydraulic deficiencies, highlighting the importance of maintaining a good thermal regime at all points within the system to control the population of L. pneumophila. PMID:27092528

A statistical treatment of bioassay pour fractions

NASA Astrophysics Data System (ADS)

Barengoltz, Jack; Hughes, David

A bioassay is a method for estimating the number of bacterial spores on a spacecraft surface for the purpose of demonstrating compliance with planetary protection (PP) requirements (Ref. 1). The details of the process may be seen in the appropriate PP document (e.g., for NASA, Ref. 2). In general, the surface is mechanically sampled with a damp sterile swab or wipe. The completion of the process is colony formation in a growth medium in a plate (Petri dish); the colonies are counted. Consider a set of samples from randomly selected, known areas of one spacecraft surface, for simplicity. One may calculate the mean and standard deviation of the bioburden density, which is the ratio of counts to area sampled. The standard deviation represents an estimate of the variation from place to place of the true bioburden density commingled with the precision of the individual sample counts. The accuracy of individual sample results depends on the equipment used, the collection method, and the culturing method. One aspect that greatly influences the result is the pour fraction, which is the quantity of fluid added to the plates divided by the total fluid used in extracting spores from the sampling equipment. In an analysis of a single sample’s counts due to the pour fraction, one seeks to answer the question: What is the probability that if a certain number of spores are counted with a known pour fraction, that there are an additional number of spores in the part of the rinse not poured. This is given for specific values by the binomial distribution density, where detection (of culturable spores) is success and the probability of success is the pour fraction. A special summation over the binomial distribution, equivalent to adding for all possible values of the true total number of spores, is performed. This distribution when normalized will almost yield the desired quantity. It is the probability that the additional number of spores does not exceed a certain value. Of course, for a desired value of uncertainty, one must invert the calculation. However, this probability of finding exactly the number of spores in the poured part is correct only in the case where all values of the true number of spores greater than or equal to the adjusted count are equally probable. This is not realistic, of course, but the result can only overestimate the uncertainty. So it is useful. In probability speak, one has the conditional probability given any true total number of spores. Therefore one must multiply it by the probability of each possible true count, before the summation. If the counts for a sample set (of which this is one sample) are available, one may use the calculated variance and the normal probability distribution. In this approach, one assumes a normal distribution and neglects the contribution from spatial variation. The former is a common assumption. The latter can only add to the conservatism (over estimate the number of spores at some level of confidence). A more straightforward approach is to assume a Poisson probability distribution for the measured total sample set counts, and use the product of the number of samples and the mean number of counts per sample as the mean of the Poisson distribution. It is necessary to set the total count to 1 in the Poisson distribution when actual total count is zero. Finally, even when the planetary protection requirements for spore burden refer only to the mean values, they require an adjustment for pour fraction and method efficiency (a PP specification based on independent data). The adjusted mean values are a 50/50 proposition (e.g., the probability of the true total counts in the sample set exceeding the estimate is 0.50). However, this is highly unconservative when the total counts are zero. No adjustment to the mean values occurs for either pour fraction or efficiency. The recommended approach is once again to set the total counts to 1, but now applied to the mean values. Then one may apply the corrections to the revised counts. It can be shown by the methods developed in this work that this change is usually conservative enough to increase the level of confidence in the estimate to 0.5. 1. NASA. (2005) Planetary protection provisions for robotic extraterrestrial missions. NPR 8020.12C, April 2005, National Aeronautics and Space Administration, Washington, DC. 2. NASA. (2010) Handbook for the Microbiological Examination of Space Hardware, NASA-HDBK-6022, National Aeronautics and Space Administration, Washington, DC.

Survey of predators and sampling method comparison in sweet corn.

PubMed

Musser, Fred R; Nyrop, Jan P; Shelton, Anthony M

2004-02-01

Natural predation is an important component of integrated pest management that is often overlooked because it is difficult to quantify and perceived to be unreliable. To begin incorporating natural predation into sweet corn, Zea mays L., pest management, a predator survey was conducted and then three sampling methods were compared for their ability to accurately monitor the most abundant predators. A predator survey on sweet corn foliage in New York between 1999 and 2001 identified 13 species. Orius insidiosus (Say), Coleomegilla maculata (De Geer), and Harmonia axyridis (Pallas) were the most numerous predators in all years. To determine the best method for sampling adult and immature stages of these predators, comparisons were made among nondestructive field counts, destructive counts, and yellow sticky cards. Field counts were correlated with destructive counts for all populations, but field counts of small insects were biased. Sticky cards underrepresented immature populations. Yellow sticky cards were more attractive to C. maculata adults than H. axyridis adults, especially before pollen shed, making coccinellid population estimates based on sticky cards unreliable. Field counts were the most precise method for monitoring adult and immature stages of the three major predators. Future research on predicting predation of pests in sweet corn should be based on field counts of predators because these counts are accurate, have no associated supply costs, and can be made quickly.

Long-term clinical and bacterial effects of xylitol on patients with fixed orthodontic appliances.

PubMed

Masoud, Mohamed I; Allarakia, Reem; Alamoudi, Najlaa M; Nalliah, Romesh; Allareddy, Veerasathpurush

2015-01-01

The objective of this study was to evaluate long-term clinical and bacterial effects of using 6 g of xylitol per day for 3 months on patients with full fixed orthodontic appliances. The study was a pilot clinical trial that included 41 subjects who were undergoing orthodontic treatment. The subjects were randomly divided into three groups. Group A received xylitol chewing gum, group B received xylitol dissolvable chewable tablets, and Group C served as the control group and did not receive xylitol gums or tablets. Clinical examination and the collection of plaque and saliva samples were carried out at baseline and 3, 6, and 12 months. All three groups were given oral hygiene instruction and were put on a 6-month cleaning and topical fluoride schedule. Plaque scores and bacterial counts were used to evaluate the effectiveness of the different approaches at reducing the caries risk. Xylitol groups did not experience any more reduction in plaque score, plaque MS counts, or salivary MS counts than the control group nor did they have lower values at any of the time points. Chewing gum did not significantly increase the incidence of debonded brackets over the other groups. Xylitol does not have a clinical or bacterial benefit in patients with fixed orthodontic appliances. Oral hygiene instructions and 6-month topical fluoride application were effective at reducing plaque scores and bacterial counts in patients with full fixed appliances regardless of whether or not xylitol was used.

Class Counts: An Overview and Response to Mr. Cooper's Review

ERIC Educational Resources Information Center

Ornstein, Allan

2009-01-01

This article presents Allan Ornstein's response to highly respected scholar, Bruce Cooper's review of Ornstein's 2007 book, "Class Counts: Education, Inequality and the Shrinking Middle Class." Here Ornstein attempts to elaborate on a few points that he felt Cooper missed in his review.

[Participation of leucocytes in pathogenesis of primary forms of lower limb chronic venous disease].

PubMed

Bogachev, V Iu; Golovanova, O V; Sergeeva, N A; Kuznetsov, A N

2011-01-01

The purpose of the study was to test the hypothesis on participation of WBCs in damaging the venous wall in patients presenting with primary forms of lower limb chronic venous diseases LLCVD . The study included a total of fifteen consecutively selected patients (13 women and 2 men) diagnosed as having grade C2-C-4 LLCVD according to the CEAP classification. Static loading (30 minutes in the sitting position) was followed by simultaneous sampling of blood from the varicose vein of the cms and ulnar vein. The total blood count including determination of both the absolute values and percentage of blood formed elements was performed using the automated haematological counter «Advia 7» («Bayer», USA). The obtained findings were statistically processed using the Microsoft Office Excel software by means of the pared two-sample τ-test for the average values. The number of leukocytes and their subpopulations in blood samples obtained from the crural varicose veins turned out to be significantly less as compared with that in blood sampled from the ulnar vein. Thus, blood sampled from the crural varicose veins demonstrated a decrease in the counts of WBC by 9.6% in fourteen (93.3%) patients, that of neutrophils by 4.9% in twelve (80%) patients, that of lymphocytes by 16,8% in fifteen (100%) patients, and that oi monocytes by 24% in twelve (80%) patients. The mentioned differences were statistically significant at a = 0.05. The eosinophilic counts in blood sampled from the upper and lower extremities appeared similar in 66.7% of the examined subjects. In 33.3% of cases the eosinophilic count in blood samples from crural varicose vein was by 16.7% lower than that for blood samples form the ulnar vein. No differences for the rest parameters of the clinical blood count were revealed. The absolute lymphocytic count in the blood samples taken after the 30-minute static loading from the crural varicose veins was significantly lower as compared with that in blood sampled form the cubital vein. The counts for RBCs and blood platelets, as well as other qualitative haematological indices (haemoglobin, haematocrit, average volume of the RBC, erythrocytic diameter, etc.) in blood sampled form crural and ulnar veins in the same patient were identical, thus strongly suggesting the lack of either haemodynamic or haemorheological phenomena capable of leading to redistribution of the blood formed elements in varicose veins. Hence a decrease in the counts of leukocytes and their subpopulations in blood sampled from crural varicose veins might be associated with the «leukocytic trap» phenomenon.

Evaluation of the Dark-Medium Objective Lens in Counting Asbestos Fibers by Phase-Contrast Microscopy

PubMed Central

Lee, Eun Gyung; Nelson, John H.; Kashon, Michael L.; Harper, Martin

2015-01-01

A Japanese round-robin study revealed that analysts who used a dark-medium (DM) objective lens reported higher fiber counts from American Industrial Hygiene Association (AIHA) Proficiency Analytical Testing (PAT) chrysotile samples than those using a standard objective lens, but the cause of this difference was not investigated at that time. The purpose of this study is to determine any major source of this difference by performing two sets of round-robin studies. For the first round-robin study, 15 AIHA PAT samples (five each of chrysotile and amosite generated by water-suspended method, and five chrysotile generated by aerosolization method) were prepared with relocatable cover slips and examined by nine laboratories. A second round-robin study was then performed with six chrysotile field sample slides by six out of nine laboratories who participated in the first round-robin study. In addition, two phase-shift test slides to check analysts’ visibility and an eight-form diatom test plate to compare resolution between the two objectives were examined. For the AIHA PAT chrysotile reference slides, use of the DM objective resulted in consistently higher fiber counts (1.45 times for all data) than the standard objective (P-value < 0.05), regardless of the filter generation (water-suspension or aerosol) method. For the AIHA PAT amosite reference and chrysotile field sample slides, the fiber counts between the two objectives were not significantly different. No statistically significant differences were observed in the visibility of blocks of the test slides between the two objectives. Also, the DM and standard objectives showed no pattern of differences in viewing the fine lines and/or dots of each species images on the eight-form diatom test plate. Among various potential factors that might affect the analysts’ performance of fiber counts, this study supports the greater contrast caused by the different phase plate absorptions as the main cause of high counts for the AIHA PAT chrysotile slides using the DM objective. The comparison of fiber count ratios (DM/standard) between the AIHA PAT chrysotile samples and chrysotile field samples indicates that there is a fraction of fibers in the PAT samples approaching the theoretical limit of visibility of the phase-contrast microscope with 3-degree phase-shift. These fibers become more clearly visible through the greater contrast from the phase plate absorption of the DM objective. However, as such fibers are not present in field samples, no difference in counts between the two objectives was observed in this study. The DM objective, therefore, could be allowed for routine fiber counting as it will maintain continuity with risk assessments based on earlier phase-contrast microscopy fiber counts from field samples. Published standard methods would need to be modified to allow a higher aperture specification for the objective. PMID:25737333

Time Evolving Fission Chain Theory and Fast Neutron and Gamma-Ray Counting Distributions

DOE PAGES

Kim, K. S.; Nakae, L. F.; Prasad, M. K.; ...

2015-11-01

Here, we solve a simple theoretical model of time evolving fission chains due to Feynman that generalizes and asymptotically approaches the point model theory. The point model theory has been used to analyze thermal neutron counting data. This extension of the theory underlies fast counting data for both neutrons and gamma rays from metal systems. Fast neutron and gamma-ray counting is now possible using liquid scintillator arrays with nanosecond time resolution. For individual fission chains, the differential equations describing three correlated probability distributions are solved: the time-dependent internal neutron population, accumulation of fissions in time, and accumulation of leaked neutronsmore » in time. Explicit analytic formulas are given for correlated moments of the time evolving chain populations. The equations for random time gate fast neutron and gamma-ray counting distributions, due to randomly initiated chains, are presented. Correlated moment equations are given for both random time gate and triggered time gate counting. There are explicit formulas for all correlated moments are given up to triple order, for all combinations of correlated fast neutrons and gamma rays. The nonlinear differential equations for probabilities for time dependent fission chain populations have a remarkably simple Monte Carlo realization. A Monte Carlo code was developed for this theory and is shown to statistically realize the solutions to the fission chain theory probability distributions. Combined with random initiation of chains and detection of external quanta, the Monte Carlo code generates time tagged data for neutron and gamma-ray counting and from these data the counting distributions.« less

Development of new photon-counting detectors for single-molecule fluorescence microscopy.

PubMed

Michalet, X; Colyer, R A; Scalia, G; Ingargiola, A; Lin, R; Millaud, J E; Weiss, S; Siegmund, Oswald H W; Tremsin, Anton S; Vallerga, John V; Cheng, A; Levi, M; Aharoni, D; Arisaka, K; Villa, F; Guerrieri, F; Panzeri, F; Rech, I; Gulinatti, A; Zappa, F; Ghioni, M; Cova, S

2013-02-05

Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences. Currently, two types of detectors best fulfil the needs of each approach: single-photon-counting avalanche diodes (SPADs) for point-like detection, and electron-multiplying charge-coupled devices (EMCCDs) for wide field detection. However, there is room for improvements in both cases. The first configuration suffers from low throughput owing to the analysis of data from a single location. The second, on the other hand, is limited to relatively low frame rates and loses the benefit of single-photon-counting approaches. During the past few years, new developments in point-like and wide field detectors have started addressing some of these issues. Here, we describe our recent progresses towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. We also discuss our development of large area photon-counting cameras achieving subnanosecond resolution for fluorescence lifetime imaging applications at the single-molecule level.

Development of new photon-counting detectors for single-molecule fluorescence microscopy

PubMed Central

Michalet, X.; Colyer, R. A.; Scalia, G.; Ingargiola, A.; Lin, R.; Millaud, J. E.; Weiss, S.; Siegmund, Oswald H. W.; Tremsin, Anton S.; Vallerga, John V.; Cheng, A.; Levi, M.; Aharoni, D.; Arisaka, K.; Villa, F.; Guerrieri, F.; Panzeri, F.; Rech, I.; Gulinatti, A.; Zappa, F.; Ghioni, M.; Cova, S.

2013-01-01

Two optical configurations are commonly used in single-molecule fluorescence microscopy: point-like excitation and detection to study freely diffusing molecules, and wide field illumination and detection to study surface immobilized or slowly diffusing molecules. Both approaches have common features, but also differ in significant aspects. In particular, they use different detectors, which share some requirements but also have major technical differences. Currently, two types of detectors best fulfil the needs of each approach: single-photon-counting avalanche diodes (SPADs) for point-like detection, and electron-multiplying charge-coupled devices (EMCCDs) for wide field detection. However, there is room for improvements in both cases. The first configuration suffers from low throughput owing to the analysis of data from a single location. The second, on the other hand, is limited to relatively low frame rates and loses the benefit of single-photon-counting approaches. During the past few years, new developments in point-like and wide field detectors have started addressing some of these issues. Here, we describe our recent progresses towards increasing the throughput of single-molecule fluorescence spectroscopy in solution using parallel arrays of SPADs. We also discuss our development of large area photon-counting cameras achieving subnanosecond resolution for fluorescence lifetime imaging applications at the single-molecule level. PMID:23267185

Evaluation of low-cost, objective instruments for assessing physical activity in 10-11-year-old children.

PubMed

Hart, Teresa L; Brusseau, Timothy; Kulinna, Pamela Hodges; McClain, James J; Tudor-Locke, Catrine

2011-12-01

This study compared step counts detected by four, low-cost, objective, physical-activity-assessment instruments and evaluated their ability to detect moderate-to-vigorous physical activity (MVPA) compared to the ActiGraph accelerometer (AG). Thirty-six 10-11-year-old children wore the NL-1000, Yamax Digiwalker SW 200, Omron HJ-151, and Walk4Life MVP concurrently with the AG during school hours on a single day. AG MVPA was derived from activity count data using previously validated cut points. Two of the evaluated instruments provided similar group mean MVPA and step counts compared to AG (dependent on cut point). Low-cost instruments may be useful for measurement of both MVPA and steps in children's physical activity interventions and program evaluation.

Preliminary design report, Large Space Telescope OTA/SI Phase B study: High speed area photometer. [systems analysis

NASA Technical Reports Server (NTRS)

1975-01-01

A photometer is examined which combines several features from separate instruments into a single package. The design presented has both point and area photometry capability with provision for inserting filters to provide spectral discrimination. The electronics provide for photon counting mode for the point detectors and both photon counting and analog modes for the area detector. The area detector also serves as a target locating device for the point detectors. Topics discussed include: (1) electronic equipment requirements, (2) optical properties, (3) structural housing for the instrument, (4) motors and other mechanical components, (5) ground support equipment, and (6) environment control for the instrument. Engineering drawings and block diagrams are shown.

Evaluating language environment analysis system performance for Chinese: a pilot study in Shanghai.

PubMed

Gilkerson, Jill; Zhang, Yiwen; Xu, Dongxin; Richards, Jeffrey A; Xu, Xiaojuan; Jiang, Fan; Harnsberger, James; Topping, Keith

2015-04-01

The purpose of this study was to evaluate performance of the Language Environment Analysis (LENA) automated language-analysis system for the Chinese Shanghai dialect and Mandarin (SDM) languages. Volunteer parents of 22 children aged 3-23 months were recruited in Shanghai. Families provided daylong in-home audio recordings using LENA. A native speaker listened to 15 min of randomly selected audio samples per family to label speaker regions and provide Chinese character and SDM word counts for adult speakers. LENA segment labeling and counts were compared with rater-based values. LENA demonstrated good sensitivity in identifying adult and child; this sensitivity was comparable to that of American English validation samples. Precision was strong for adults but less so for children. LENA adult word count correlated strongly with both Chinese characters and SDM word counts. LENA conversational turn counts correlated similarly with rater-based counts after the exclusion of three unusual samples. Performance related to some degree to child age. LENA adult word count and conversational turn provided reasonably accurate estimates for SDM over the age range tested. Theoretical and practical considerations regarding LENA performance in non-English languages are discussed. Despite the pilot nature and other limitations of the study, results are promising for broader cross-linguistic applications.

Critical control points for foods prepared in households whose members had either alleged typhoid fever or diarrhea.

PubMed

Michanie, S; Bryan, F L; Alvarez, P; Olivo, A B; Paniagua, A

1988-10-01

Hazard analysis of food preparation practices were conducted in four households and eleven others were visited to survey both food preparation practices and environmental conditions. Households selected had members who were suffering from either diarrhea of unknown etiology or alleged typhoid fever. Hazard analyses and sanitary surveys included gathering data on time-temperature exposures of foods, collecting samples of food and drinking water, sampling sewage or drains, and obtaining stool specimens from persons with diarrhea and from family controls. Food samples were tested for aerobic mesophilic colony counts and common foodborne pathogens; specimens were tested for Salmonella, Shigella, Campylobacter and Yersinia. Campylobacter was isolated from two persons purported to have diarrhea, but neither Salmonella, Shigella nor Yersinia were recovered from alleged cases or controls. Salmonella agona was recovered from a latrine. Most foods were cooked to internal temperatures to or near to boiling. Those not promptly eaten were held at ambient room or outside temperatures until a subsequent meal, until a family member returned home, or until lunch time when taken to the fields. During these intervals, microorganisms multiplied and mesophilic aerobic organisms increased often reaching 10(8)/g or greater before consumption. None of these foods were reheated before eating. Bacillus cereus was isolated from 4 of 10 samples; one sample of 'moro' (beans and rice) exceeded 10(6)/g, two other samples exceeded 10(3)/g. Staphylococcus aureus was isolated from 7 of 14 samples, one exceeded 10(5)/g. Fecal coliforms were isolated from 8 of 14 food samples, five exceeded 10(5)/g. Neither Salmonella nor Shigella were isolated from any food, the community water supplies or from vessels of water within houses. Fecal coliform counts of water were less than 3/ml, except one sample from a clay vessel (9/ml). Risks associated with cooked foods which were not promptly eaten appeared to be greater than that associated with water.

Progression of ash canopy thinning and dieback outward from the initial infestation of emerald ash borer (Coleoptera: Buprestidae) in southeastern Michigan.

PubMed

Smitley, David; Davis, Terrance; Rebek, Eric

2008-10-01

Our objective was to characterize the rate at which ash (Fraxinus spp.) trees decline in areas adjacent to the leading edge of visible ash canopy thinning due to emerald ash borer, Agrilus planipennis Fairmaire (Coleoptera: Buprestidae). Trees in southeastern Michigan were surveyed from 2003 to 2006 for canopy thinning and dieback by comparing survey trees with a set of 11 standard photographs. Freeways stemming from Detroit in all directions were used as survey transects. Between 750 and 1,100 trees were surveyed each year. A rapid method of sampling populations of emerald ash borer was developed by counting emerald ash borer emergence holes with binoculars and then felling trees to validate binocular counts. Approximately 25% of the trees surveyed for canopy thinning in 2005 and 2006 also were sampled for emerald ash borer emergence holes using binoculars. Regression analysis indicates that 41-53% of the variation in ash canopy thinning can be explained by the number of emerald ash borer emergence holes per tree. Emerald ash borer emergence holes were found at every site where ash canopy thinning averaged > 40%. In 2003, ash canopy thinning averaged 40% at a distance of 19.3 km from the epicenter of the emerald ash borer infestation in Canton. By 2006, the point at which ash trees averaged 40% canopy thinning had increased to a distance of 51.2 km away from Canton. Therefore, the point at which ash trees averaged 40% canopy thinning, a state of decline clearly visible to the average person, moved outward at a rate of 10.6 km/yr during this period.

Inventory of montane-nesting birds in the Arctic Network of National Parks, Alaska

USGS Publications Warehouse

Tibbitts, T.L.; Ruthrauff, D.R.; Gill, Robert E.; Handel, Colleen M.

2006-01-01

The Alaska Science Center of the U.S. Geological Survey conducted an inventory of birds in montane areas of the four northern parks in the Arctic Network of National Parks, Alaska. This effort represents the first comprehensive assessment of breeding range and habitat associations for the majority of avian species in the Arctic Network. Ultimately, these data provide a framework upon which to design future monitoring programs.A stratified random sampling design was used to select sample plots (n = 73 plots) that were allocated in proportion to the availability of ecological subsections. Point counts (n = 1,652) were conducted to quantify abundance, distribution, and habitat associations of birds. Field work occurred over three years (2001 to 2003) during two-week-long sessions in late May through early June that coincided with peak courtship activity of breeding birds.Totals of 53 species were recorded in Cape Krusenstern National Monument, 91 in Noatak National Preserve, 57 in Kobuk Valley National Park, and 96 in Gates of the Arctic National Park and Preserve. Substantial proportions of species in individual parks are considered species of conservation concern (18 to 26%) or species of stewardship responsibility of the land managers in the region (8 to 18%). The most commonly detected passerines on point counts included Redpoll spp. (Carduelis flammea and C. hornemanni), Savannah Sparrow (Passerculus sandwichensis), and American Tree Sparrow (Spizella arborea). The most numerous shorebirds were American Golden-Plover (Pluvialis dominica), Wilson’s Snipe (Gallinago delicata), and Whimbrel (Numenius phaeopus). Most species were detected at low rates, reflecting the low breeding densities (and/or low detectabilities) of birds in the montane Arctic. Suites of species were associated with particular ranges of elevation and showed strong associations with particular habitat types.

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

Kim, K. S.; Nakae, L. F.; Prasad, M. K.

Here, we solve a simple theoretical model of time evolving fission chains due to Feynman that generalizes and asymptotically approaches the point model theory. The point model theory has been used to analyze thermal neutron counting data. This extension of the theory underlies fast counting data for both neutrons and gamma rays from metal systems. Fast neutron and gamma-ray counting is now possible using liquid scintillator arrays with nanosecond time resolution. For individual fission chains, the differential equations describing three correlated probability distributions are solved: the time-dependent internal neutron population, accumulation of fissions in time, and accumulation of leaked neutronsmore » in time. Explicit analytic formulas are given for correlated moments of the time evolving chain populations. The equations for random time gate fast neutron and gamma-ray counting distributions, due to randomly initiated chains, are presented. Correlated moment equations are given for both random time gate and triggered time gate counting. There are explicit formulas for all correlated moments are given up to triple order, for all combinations of correlated fast neutrons and gamma rays. The nonlinear differential equations for probabilities for time dependent fission chain populations have a remarkably simple Monte Carlo realization. A Monte Carlo code was developed for this theory and is shown to statistically realize the solutions to the fission chain theory probability distributions. Combined with random initiation of chains and detection of external quanta, the Monte Carlo code generates time tagged data for neutron and gamma-ray counting and from these data the counting distributions.« less

Lower white blood cell counts in elite athletes training for highly aerobic sports.

PubMed

Horn, P L; Pyne, D B; Hopkins, W G; Barnes, C J

2010-11-01

White cell counts at rest might be lower in athletes participating in selected endurance-type sports. Here, we analysed blood tests of elite athletes collected over a 10-year period. Reference ranges were established for 14 female and 14 male sports involving 3,679 samples from 937 females and 4,654 samples from 1,310 males. Total white blood cell counts and counts of neutrophils, lymphocytes and monocytes were quantified. Each sport was scaled (1-5) for its perceived metabolic stress (aerobic-anaerobic) and mechanical stress (concentric-eccentric) by 13 sports physiologists. Substantially lower total white cell and neutrophil counts were observed in aerobic sports of cycling and triathlon (~16% of test results below the normal reference range) compared with team or skill-based sports such as water polo, cricket and volleyball. Mechanical stress of sports had less effect on the distribution of cell counts. The lower white cell counts in athletes in aerobic sports probably represent an adaptive response, not underlying pathology.

Regression analysis of mixed panel count data with dependent terminal events.

PubMed

Yu, Guanglei; Zhu, Liang; Li, Yang; Sun, Jianguo; Robison, Leslie L

2017-05-10

Event history studies are commonly conducted in many fields, and a great deal of literature has been established for the analysis of the two types of data commonly arising from these studies: recurrent event data and panel count data. The former arises if all study subjects are followed continuously, while the latter means that each study subject is observed only at discrete time points. In reality, a third type of data, a mixture of the two types of the data earlier, may occur and furthermore, as with the first two types of the data, there may exist a dependent terminal event, which may preclude the occurrences of recurrent events of interest. This paper discusses regression analysis of mixed recurrent event and panel count data in the presence of a terminal event and an estimating equation-based approach is proposed for estimation of regression parameters of interest. In addition, the asymptotic properties of the proposed estimator are established, and a simulation study conducted to assess the finite-sample performance of the proposed method suggests that it works well in practical situations. Finally, the methodology is applied to a childhood cancer study that motivated this study. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Changes in the microbiological quality of mangrove oysters (Crassostrea brasiliana) during different storage conditions.

PubMed

Montanhini, Maike Taís Maziero; Montanhini Neto, Roberto

2015-01-01

This study aimed to determine the effect of temperature and period of postharvest storage on the microbiological quality and shelf life of raw mangrove oysters, Crassostrea brasiliana. A total of 150 dozen oysters were collected directly from the points of extraction or cultivation in southern Brazil, and in the laboratory, they were stored raw at 5, 10, 15, 20, and 25°C for 1, 4, 8, 11, and 15 days. On each of these days, the oysters were subjected to microbiological analyses of aerobic mesophilic count, total coliforms, enterococci, Escherichia coli, Staphylococcus aureus, and Salmonella. None of the tested samples under any storage condition showed contamination levels above those allowed by Brazilian legislation for E. coli, S. aureus, and Salmonella, and there was no change (P > 0.05) in the counts of these microorganisms due to the temperature and/or period of oyster storage. Counts of enterococci and total coliforms showed a tendency to increase (P < 0.05) among the different temperatures tested. Raw mangrove oysters remain in safe microbiological conditions for consumption up to 8 days after harvesting, regardless of temperature, and their shelf life may be extended to 15 days if they are stored at temperatures not exceeding 15°C.

Point-of-care C-reactive protein-based tuberculosis screening for people living with HIV: a diagnostic accuracy study.

PubMed

Yoon, Christina; Semitala, Fred C; Atuhumuza, Elly; Katende, Jane; Mwebe, Sandra; Asege, Lucy; Armstrong, Derek T; Andama, Alfred O; Dowdy, David W; Davis, J Luke; Huang, Laurence; Kamya, Moses; Cattamanchi, Adithya

2017-12-01

Symptom-based screening for tuberculosis is recommended for all people living with HIV. This recommendation results in unnecessary Xpert MTB/RIF testing in many individuals living in tuberculosis-endemic areas and thus poor implementation of intensified case finding and tuberculosis preventive therapy. Novel approaches to tuberculosis screening are needed to help achieve global targets for tuberculosis elimination. We assessed the performance of C-reactive protein (CRP) measured with a point-of-care assay as a screening tool for active pulmonary tuberculosis. For this prospective study, we enrolled adults (aged ≥18 years) living with HIV with CD4 cell count less than or equal to 350 cells per μL who were initiating antiretroviral therapy (ART) from two HIV/AIDS clinics in Uganda. CRP concentrations were measured at study entry with a point-of-care assay using whole blood obtained by fingerprick (concentration ≥10 mg/L defined as screen positive for tuberculosis). Sputum samples were collected for Xpert MTB/RIF testing and culture. We calculated the sensitivity and specificity of point-of-care CRP and WHO symptom-based screening in reference to culture results. We repeated the sensitivity analysis with Xpert MTB/RIF as the reference standard. Between July 8, 2013, and Dec 15, 2015, 1237 HIV-infected adults were enrolled and underwent point-of-care CRP testing. 60 (5%) patients with incomplete or contaminated cultures were excluded from the analysis. Of the remaining 1177 patients (median CD4 count 165 cells per μL [IQR 75-271]), 163 (14%) had culture-confirmed tuberculosis. Point-of-care CRP testing had 89% sensitivity (145 of 163, 95% CI 83-93) and 72% specificity (731 of 1014, 95% CI 69-75) for culture-confirmed tuberculosis. Compared with WHO symptom-based screening, point-of-care CRP testing had lower sensitivity (difference -7%, 95% CI -12 to -2; p=0·002) but substantially higher specificity (difference 58%, 95% CI 55 to 61; p<0·0001). When Xpert MTB/RIF results were used as the reference standard, sensitivity of point-of-care CRP and WHO symptom-based screening were similar (94% [79 of 84] vs 99% [83 of 84], respectively; difference -5%, 95% CI -12 to 2; p=0·10). The performance characteristics of CRP support its use as a tuberculosis screening test for people living with HIV with CD4 count less than or equal to 350 cells per μL who are initiating ART. HIV/AIDS programmes should consider point-of-care CRP-based tuberculosis screening to improve the efficiency of intensified case finding and increase uptake of tuberculosis preventive therapy. National Institutes of Health; President's Emergency Plan for AIDS Relief; University of California, San Francisco, Nina Ireland Program for Lung Health. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sources and magnitude of sampling error in redd counts for bull trout

Treesearch

Jason B. Dunham; Bruce Rieman

2001-01-01

Monitoring of salmonid populations often involves annual redd counts, but the validity of this method has seldom been evaluated. We conducted redd counts of bull trout Salvelinus confluentus in two streams in northern Idaho to address four issues: (1) relationships between adult escapements and redd counts; (2) interobserver variability in redd...

Portable point-of-care blood analysis system for global health (Conference Presentation)

NASA Astrophysics Data System (ADS)

Dou, James J.; Aitchison, James Stewart; Chen, Lu; Nayyar, Rakesh

2016-03-01

In this paper we present a portable blood analysis system based on a disposable cartridge and hand-held reader. The platform can perform all the sample preparation, detection and waste collection required to complete a clinical test. In order to demonstrate the utility of this approach a CD4 T cell enumeration was carried out. A handheld, point-of-care CD4 T cell system was developed based on this system. In particular we will describe a pneumatic, active pumping method to control the on-chip fluidic actuation. Reagents for the CD4 T cell counting assay were dried on a reagent plug to eliminate the need for cold chain storage when used in the field. A micromixer based on the active fluidic actuation was designed to complete sample staining with fluorescent dyes that was dried on the reagent plugs. A novel image detection and analysis algorithm was developed to detect and track the flight of target particles and cells during each analysis. The handheld, point-of-care CD4 testing system was benchmarked against clinical cytometer. The experimental results demonstrated experimental results were closely matched with the flow cytometry. The same platform can be further expanded into a bead-array detection system where other types of biomolecules such as proteins can be detected using the same detection system.

In vivo antimicrobial efficacy of 6% Morinda citrifolia, Azadirachta indica, and 3% sodium hypochlorite as root canal irrigants.

PubMed

Podar, Rajesh; Kulkarni, Gaurav P; Dadu, Shifali S; Singh, Shraddha; Singh, Shishir H

2015-01-01

To evaluate and compare the antimicrobial efficacy of 6% Morinda citrifolia, Azadirachta indica, and 3% sodium hypochlorite (NaOCl) as root canal irrigants. Thirty nonvital maxillary anteriors were randomly assigned to one of the three groups corresponding to the irrigant to be tested; 6% Morinda citrifolia juice (MCJ) (n = 10), A. indica (n = 10) and 3% NaOCl (n = 10). After the root canal access opening a root canal culture sample was taken with two paper points and cultured under aerobic and anaerobic conditions. Cleaning and shaping were completed with irrigation by 10 mL of respective irrigants and 5 mL of final rinse. The patients were recalled after 3 days and canals were rinsed again with 5 mL of the test irrigants. This was followed by obtaining a posttreatment root canal culture sample and culturing and analyzed by counting the colony forming units (CFUs). Six percentage MCJ, A. indica, and 3% NaOCl showed a significant reduction (P < 0.05) in the mean CFU counts for aerobic and anaerobic bacteria between baseline and 3 days. There was no difference in the antimicrobial efficacy of 6% M. citrifolia, A. indica, and 3% NaOCl as root canal irrigants.

Evaluating the ability of regional models to predict local avian abundance

USGS Publications Warehouse

LeBrun, Jaymi J.; Thogmartin, Wayne E.; Miller, James R.

2012-01-01

Spatial modeling over broad scales can potentially direct conservation efforts to areas with high species-specific abundances. We examined the performance of regional models for predicting bird abundance at spatial scales typically addressed in conservation planning. Specifically, we used point count data on wood thrush (Hylocichla mustelina) and blue-winged warbler (Vermivora cyanoptera) from 2 time periods (1995-1998 and 2006-2007) to evaluate the ability of regional models derived via Bayesian hierarchical techniques to predict bird abundance. We developed models for each species within Bird Conservation Region (BCR) 23 in the upper midwestern United States at 800-ha, 8,000-ha, and approximately 80,000-ha scales. We obtained count data from the Breeding Bird Survey and land cover data from the National Land Cover Dataset (1992). We evaluated predictions from the best models, as defined by an information-theoretic criterion, using point count data collected within an ecological subregion of BCR 23 at 131 count stations in the 1990s and again in 2006-2007. Competing (Deviance Information Criteria rs = 0.57; P = 0.14), the survey period that most closely aligned with the time period of data used for regional model construction. Wood thrush models exhibited positive correlations with point count data for all survey areas and years combined (rs = 0.58, P ≤ 0.001). In comparison, blue-winged warbler models performed worse as time increased between the point count surveys and vintage of the model building data (rs = 0.03, P = 0.92 for Iowa and rs = 0.13, P = 0.51 for all areas, 2006-2007), likely related to the ephemeral nature of their preferred early successional habitat. Species abundance and sensitivity to changing habitat conditions seems to be an important factor in determining the predictive ability of regional models. Hierarchical models can be a useful tool for concentrating efforts at the scale of management units and should be one of many tools used by land managers, but we caution that the utility of such models may decrease over time for species preferring relatively ephemeral habitats if model inputs are not updated accordingly.

Microbial contamination of cosmetics and personal care items in Egypt--body lotions and talcum powders.

PubMed

Ashour, M S; Abdelaziz, A A; Hefni, H; el-Tayeb, O M

1989-06-01

We examined a total of 54 samples, including 18 body lotions and 36 talcum powders, for their total aerobic bacterial, coliform and fungal counts. We also carried out anaerobic bacterial counts for talcum powder as well as tests to detect some potentially hazardous bacteria in all tested samples. Talcum powders were more heavily contaminated with bacteria and fungi than body lotions. More than 40% of the tested body lotions contained no viable bacteria or less than 100 c.f.u./g. while all the talcum powders tested contained more than 100 c.f.u./g. Thirty per cent of the talcum powders were contaminated with 10(4) c.f.u./g. and none of the body lotions were contaminated to that extent. No coliforms were recovered from any of the body lotions, while 17% of the talcum powder examined contained coliforms in the range of 230-500 c.f.u./g. Staphylococcus spp. were detected in 18 samples of both talcum powders and body lotions, three of these Staphylococci were of the aureus type. Three samples of talcum powder contained E. coli, two samples contained Enterobacter agglomerans and one sample contained Citrobacter freundii. Seventy per cent of the body lotions showed no fungal counts, while 83% of the talcum powders examined were contaminated with fungi and most of the contaminated talcum powders contained more than 100 fungal cells/g. With regard to the anaerobic bacterial counts for talcum powders, 50% of the samples showed no counts while the other 50% contained less than 100 c.f.u./g. Four samples were contaminated with Clostridium perfringens, although C. tetani was not recovered from any of the samples.

Operating characteristics of full count and binomial sampling plans for green peach aphid (Hemiptera: Aphididae) in potato.

PubMed

Kabaluk, J Todd; Binns, Michael R; Vernon, Robert S

2006-06-01

Counts of green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae), in potato, Solanum tuberosum L., fields were used to evaluate the performance of the sampling plan from a pest management company. The counts were further used to develop a binomial sampling method, and both full count and binomial plans were evaluated using operating characteristic curves. Taylor's power law provided a good fit of the data (r2 = 0.95), with the relationship between the variance (s2) and mean (m) as ln(s2) = 1.81(+/- 0.02) + 1.55(+/- 0.01) ln(m). A binomial sampling method was developed using the empirical model ln(m) = c + dln(-ln(1 - P(T))), to which the data fit well for tally numbers (T) of 0, 1, 3, 5, 7, and 10. Although T = 3 was considered the most reasonable given its operating characteristics and presumed ease of classification above or below critical densities (i.e., action thresholds) of one and 10 M. persicae per leaf, the full count method is shown to be superior. The mean number of sample sites per field visit by the pest management company was 42 +/- 19, with more than one-half (54%) of the field visits involving sampling 31-50 sample sites, which was acceptable in the context of operating characteristic curves for a critical density of 10 M. persicae per leaf. Based on operating characteristics, actual sample sizes used by the pest management company can be reduced by at least 50%, on average, for a critical density of 10 M. persicae per leaf. For a critical density of one M. persicae per leaf used to avert the spread of potato leaf roll virus, sample sizes from 50 to 100 were considered more suitable.

Results from raw milk microbiological tests do not predict the shelf-life performance of commercially pasteurized fluid milk.

PubMed

Martin, N H; Ranieri, M L; Murphy, S C; Ralyea, R D; Wiedmann, M; Boor, K J

2011-03-01

Analytical tools that accurately predict the performance of raw milk following its manufacture into commercial food products are of economic interest to the dairy industry. To evaluate the ability of currently applied raw milk microbiological tests to predict the quality of commercially pasteurized fluid milk products, samples of raw milk and 2% fat pasteurized milk were obtained from 4 New York State fluid milk processors for a 1-yr period. Raw milk samples were examined using a variety of tests commonly applied to raw milk, including somatic cell count, standard plate count, psychrotrophic bacteria count, ropy milk test, coliform count, preliminary incubation count, laboratory pasteurization count, and spore pasteurization count. Differential and selective media were used to identify groups of bacteria present in raw milk. Pasteurized milk samples were held at 6°C for 21 d and evaluated for standard plate count, coliform count, and sensory quality throughout shelf-life. Bacterial isolates from select raw and pasteurized milk tests were identified using 16S ribosomal DNA sequencing. Linear regression analysis of raw milk test results versus results reflecting pasteurized milk quality consistently showed low R(2) values (<0.45); the majority of R(2) values were <0.25, indicating small relationship between the results from the raw milk tests and results from tests used to evaluate pasteurized milk quality. Our findings suggest the need for new raw milk tests that measure the specific biological barriers that limit shelf-life and quality of fluid milk products. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of high pressure treatment on liquid whole egg

NASA Astrophysics Data System (ADS)

Németh, Csaba; Dalmadi, István; Mráz, Balázs; Friedrich, László; Zeke, Ildikó; Juhász, Réka; Suhajda, Ágnes; Balla, Csaba

2012-06-01

In our tests, we artificially infected liquid whole egg samples with Salmonella enteritidis, Listeria monocytogenes, and Staphylococcus aureus bacteria, and then treated the samples in "Food Lab900" high hydrostatic pressure (HHP) instrument for 3-17 min at 200-400 MPa. Subsequently, the change of the viable cell count of the specific bacteria has been tested. In addition to the samples infected with various bacteria, non-infected samples were also treated in each test and the change in viable cell count, colour and viscosity of the samples upon the effect of the treatment. In summary, it can be concluded that in each test of our investigations, the viable cell count of S. enteritidis critical for egg products is reduced significantly, while the reduction of the total viable cell count was around two magnitudes. Additionally, based on our results, microbial destruction, reduction of enthalpy (denaturation of egg white) caused by the treatment at HPP, and colour change are primarily affected by the pressure level, while the changes in rheological properties are also significantly affected by the duration of high pressure treatment (p<0.05).

Neutron coincidence counting based on time interval analysis with one- and two-dimensional Rossi-alpha distributions: an application for passive neutron waste assay

NASA Astrophysics Data System (ADS)

Bruggeman, M.; Baeten, P.; De Boeck, W.; Carchon, R.

1996-02-01

Neutron coincidence counting is commonly used for the non-destructive assay of plutonium bearing waste or for safeguards verification measurements. A major drawback of conventional coincidence counting is related to the fact that a valid calibration is needed to convert a neutron coincidence count rate to a 240Pu equivalent mass ( 240Pu eq). In waste assay, calibrations are made for representative waste matrices and source distributions. The actual waste however may have quite different matrices and source distributions compared to the calibration samples. This often results in a bias of the assay result. This paper presents a new neutron multiplicity sensitive coincidence counting technique including an auto-calibration of the neutron detection efficiency. The coincidence counting principle is based on the recording of one- and two-dimensional Rossi-alpha distributions triggered respectively by pulse pairs and by pulse triplets. Rossi-alpha distributions allow an easy discrimination between real and accidental coincidences and are aimed at being measured by a PC-based fast time interval analyser. The Rossi-alpha distributions can be easily expressed in terms of a limited number of factorial moments of the neutron multiplicity distributions. The presented technique allows an unbiased measurement of the 240Pu eq mass. The presented theory—which will be indicated as Time Interval Analysis (TIA)—is complementary to Time Correlation Analysis (TCA) theories which were developed in the past, but is from the theoretical point of view much simpler and allows a straightforward calculation of deadtime corrections and error propagation. Analytical expressions are derived for the Rossi-alpha distributions as a function of the factorial moments of the efficiency dependent multiplicity distributions. The validity of the proposed theory is demonstrated and verified via Monte Carlo simulations of pulse trains and the subsequent analysis of the simulated data.

[Incidence of Campylobacter spp. and Salmonella spp. in raw and roasted chicken in Guadalajara, Mexico].

PubMed

Castillo-Ayala, A; Salas-Ubiarco, M G; Márquez-Padilla, M L; Osorio-Hernández, M D

1993-01-01

The presence of Campylobacter spp. and Salmonella was studied in 70 samples of fresh retail chicken pieces and in 40 samples of roast chicken. Total plate count was performed in every sample as well. Most of the samples of fresh chicken yielded total plate counts > 10(8)/piece (thigh), while in roast chicken these counts ranged from 10(3) to 10(5)/piece (leg and thigh). Campylobacter was isolated from 33% of fresh chicken and from no sample of roast chicken. Salmonella was isolated from 69% of fresh chicken and 2.5% of roast chicken. There was no relationship between total plate counts in fresh chicken and isolation of either Campylobacter or Salmonella. Sixty percent of the Salmonella isolates belonged to serotype S. anatum, and about 50% of the isolates of Campylobacter were identified as being C. coli. The only Salmonella-positive sample of roast chicken yielded three serotypes: S. give, S. muenster, and S. manhattan. Presence of Campylobacter and Salmonella in chicken is of concern, due to the risk of spreading from the raw food to other cooked foods. The isolation of pathogens from roast chicken indicates mishandling during processing and/or storage of the product.

Development of a Low-Level Ar-37 Calibration Standard

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

Williams, Richard M.; Aalseth, Craig E.; Bowyer, Ted W.

Argon-37 is an important environmental signature of an underground nuclear explosion. Producing and quantifying low-level 37Ar standards is an important step in the development of sensitive field measurement instruments for use during an On-Site Inspection, a key provision of the Comprehensive Nuclear-Test-Ban Treaty. This paper describes progress at Pacific Northwest National Laboratory (PNNL) in the development of a process to generate and quantify low-level 37Ar standard material, which can then be used to calibrate sensitive field systems at activities consistent with soil background levels. The 37Ar used for our work was generated using a laboratory-scale, high-energy neutron source to irradiatemore » powdered samples of calcium carbonate. Small aliquots of 37Ar were then extracted from the head space of the irradiated samples. The specific activity of the head space samples, mixed with P10 (90% stable argon:10% methane by mole fraction) count gas, is then derived using the accepted Length-Compensated Internal-Source Proportional Counting method. Due to the low activity of the samples, a set of three Ultra-Low Background Proportional-Counters designed and fabricated at PNNL from radio-pure electroformed copper was used to make the measurements in PNNL’s shallow underground counting laboratory. Very low background levels (<10 counts/day) have been observed in the spectral region near the 37Ar emission feature at 2.8 keV. Two separate samples from the same irradiation were measured. The first sample was counted for 12 days beginning 28 days after irradiation, the second sample was counted for 24 days beginning 70 days after irradiation (the half-life of 37Ar is 35.0 days). Both sets of measurements were analyzed and yielded very similar results for the starting activity (~0.1 Bq) and activity concentration (0.15 mBq/ccSTP argon) after P10 count gas was added. A detailed uncertainty model was developed based on the ISO Guide to the Expression of Uncertainty in Measurement. This paper presents a discussion of the measurement analysis, along with assumptions and uncertainty estimates.« less

A New Method for Estimating Bacterial Abundances in Natural Samples using Sublimation

NASA Technical Reports Server (NTRS)

Glavin, Daniel P.; Cleaves, H. James; Schubert, Michael; Aubrey, Andrew; Bada, Jeffrey L.

2004-01-01

We have developed a new method based on the sublimation of adenine from Escherichia coli to estimate bacterial cell counts in natural samples. To demonstrate this technique, several types of natural samples including beach sand, seawater, deep-sea sediment, and two soil samples from the Atacama Desert were heated to a temperature of 500 C for several seconds under reduced pressure. The sublimate was collected on a cold finger and the amount of adenine released from the samples then determined by high performance liquid chromatography (HPLC) with UV absorbance detection. Based on the total amount of adenine recovered from DNA and RNA in these samples, we estimated bacterial cell counts ranging from approx. l0(exp 5) to l0(exp 9) E. coli cell equivalents per gram. For most of these samples, the sublimation based cell counts were in agreement with total bacterial counts obtained by traditional DAPI staining. The simplicity and robustness of the sublimation technique compared to the DAPI staining method makes this approach particularly attractive for use by spacecraft instrumentation. NASA is currently planning to send a lander to Mars in 2009 in order to assess whether or not organic compounds, especially those that might be associated with life, are present in Martian surface samples. Based on our analyses of the Atacama Desert soil samples, several million bacterial cells per gam of Martian soil should be detectable using this sublimation technique.

Sampling Strategies and Processing of Biobank Tissue Samples from Porcine Biomedical Models.

PubMed

Blutke, Andreas; Wanke, Rüdiger

2018-03-06

In translational medical research, porcine models have steadily become more popular. Considering the high value of individual animals, particularly of genetically modified pig models, and the often-limited number of available animals of these models, establishment of (biobank) collections of adequately processed tissue samples suited for a broad spectrum of subsequent analyses methods, including analyses not specified at the time point of sampling, represent meaningful approaches to take full advantage of the translational value of the model. With respect to the peculiarities of porcine anatomy, comprehensive guidelines have recently been established for standardized generation of representative, high-quality samples from different porcine organs and tissues. These guidelines are essential prerequisites for the reproducibility of results and their comparability between different studies and investigators. The recording of basic data, such as organ weights and volumes, the determination of the sampling locations and of the numbers of tissue samples to be generated, as well as their orientation, size, processing and trimming directions, are relevant factors determining the generalizability and usability of the specimen for molecular, qualitative, and quantitative morphological analyses. Here, an illustrative, practical, step-by-step demonstration of the most important techniques for generation of representative, multi-purpose biobank specimen from porcine tissues is presented. The methods described here include determination of organ/tissue volumes and densities, the application of a volume-weighted systematic random sampling procedure for parenchymal organs by point-counting, determination of the extent of tissue shrinkage related to histological embedding of samples, and generation of randomly oriented samples for quantitative stereological analyses, such as isotropic uniform random (IUR) sections generated by the "Orientator" and "Isector" methods, and vertical uniform random (VUR) sections.

Isolation of microbial pathogens of subclinical mastitis from raw sheep's milk of Epirus (Greece) and their role in its hygiene.

PubMed

Fotou, K; Tzora, A; Voidarou, Ch; Alexopoulos, A; Plessas, S; Avgeris, I; Bezirtzoglou, E; Akrida-Demertzi, K; Demertzis, P G

2011-12-01

The natural raw milk microflora is a factor that expresses its sensorial characteristics. The microbial charge into the mammary gland of healthy animal is low and the application of right and healthy conditions during milking and cheese making procedure, prevents from contaminating as well as maintains the natural microflora in order to lend the particular characteristics of milk. The purpose of the present project was the study of the Total Viable Count (T.V.C.) and the count of total psychrotropic bacteria of raw sheep milk from Boutsiko and Karamaniko breeds, collected from healthy animals, as well as the isolation, identification and enumeration of pathogenic bacteria related with the hygiene and the quality of raw sheep milk (with a particular interest in bacteria that may cause human infection). During the experiment we examined two hundred forty (240) samples of raw sheep milk. In these samples a) Staphylococcus aureus, Salmonella sp., Escherichia coli, Clostridium perfringens (vegetative cells and spores) and Bacillus sp. were isolated and identified b) the Total Viable Count and the total number of psychrotropic bacteria were also specified. The sampling, the preparation of samples and decimal dilutions were based on international methods. The Total viable count was determined using the standard methods of the American Public Health Association, 2002. The total number of psychrotropic bacteria was determined using APHA 1976, 1978 rules. The identification of the bacteria was carried out according to the Bergey's manual. Microscopic examination of Gram stained cells, catalase, oxidase and biochemical tests were performed when necessary to further identify. From the 240 milk samples tested, only 5% were E. coli positive, with mean counts ranged from 2 × 10(3) to 2.4 × 10(4) cfu/ml. S. aureus was isolated from 24% of the samples and the mean count per ml was ranged from <10 to 3.4 × 10(2). Meanwhile, Bacillus spp. was also detected in 29% samples. Vegetative forms and spores of C. perfringens were detected in 13% and 63% of the samples respectively. However, microbiological analyses revealed the presence of a small number of selected pathogens in milk samples such as Salmonella, which was only detected in 5% of the samples. Listeria sp., Pseudomonas sp. and Vibrio cholerae were never found. From the experimental results, the Total Viable Count from raw sheep milk samples, fulfils the microbiological criteria of EU Legislation in a percentage of approximately 97%. Copyright © 2011 Elsevier Ltd. All rights reserved.

Toward unstained cytology and complete blood counts at the point of care (Conference Presentation)

NASA Astrophysics Data System (ADS)

Zuluaga, Andres F.; Pierce, Mark C.; MacAulay, Calum E.

2017-02-01

Cytology tests, whether performed on body fluids, aspirates, or scrapings are commonly used to detect, diagnose, and monitor a wide variety of health conditions. Complete blood counts (CBCs) quantify the number of red and white blood cells in a blood volume, as well as the different types of white blood cells. There is a critical unmet need for an instrument that can perform CBCs at the point of care (POC), and there is currently no product in the US that can perform this test at the bedside. We have developed a system that is capable of tomographic images with sub-cellular resolution with consumer-grade broadband (LED) sources and CMOS detectors suitable for POC implementation of CBC tests. The systems consists of cascaded static Michelson and Sagnac interferometers that map phase (encoding depth) and a transverse spatial dimension onto a two-dimensional output plane. Our approach requires a 5 microliter sample, can be performed in 5 minutes or less, and does not require staining or other processing as it relies on intrinsic contrast. We will show results directly imaging and differentiating unstained blood cells using supercontinuum fiber lasers and LEDs as sources and CMOS cameras as sensors. We will also lay out the follow up steps needed, including image segmentation, analysis and classification, to verify performance and advance toward CBCs that can be performed bedside and do not require CLIA-certified laboratories.

The contribution of mammary infections by coagulase-negative staphylococci to the herd bulk milk somatic cell count.

PubMed

Rainard, P; Ducelliez, M; Poutrel, B

1990-01-01

Quarter foremilk samples were taken at 2-3 weekly intervals for several years in an experimental herd comprising about 45 cows. The samples were submitted to bacteriological analysis and somatic cell counting. The most prevalent quarter infections from 1982 to 1988 were by coagulase-negative staphylococci (15-20% of all the quarters sampled). Most of these (75.6%) persisted until drying-off. Dry cow therapy eliminated 86.5% of these infections. Comparison of udder quarters within cows, involving 775 samples from pairs of non-infected quarters and quarters infected by coagulase-negative staphylococci, yielded geometric means of somatic cell counts of 210,000 and 420,000 cells/ml, respectively. The correlation (r = 0.87) between the herd bulk milk somatic cell count (SCC) and its estimation from the quarter milk somatic cell count performed on the same day allowed us to evaluate the contribution of the different categories of quarters, according to their infection status, to the herd bulk milk SCC. Quarters infected by a major pathogen (8.5% of samples) gave rise to 46.6% of the total number of cells, while quarters infected by coagulase-negative staphylococci (17.8% of samples) gave rise to 18.1%. Although coagulase-negative staphylococci represented only a secondary source of somatic cells as compared to major pathogens, they were not a negligible source considering the threshold of 300,000 somatic cells advocated for herd milk of good quality.

Coliform MPN counts of municipal raw sewage and sewage treatment plant in relation to the water of Buckingham Canal at Kalpakkam (Tamil Nadu, India).

PubMed

Kumar, A Yudhistra; Reddy, M Vikram

2008-01-01

Most Probable Number (MPN) of Total Coliforms (TC) and Faecal Coliforms (FC), and the physicochemical variables - temperature, Dissolved Oxygen (D.O.), Biochemical Oxygen Demand (B.O.D.), Chemical Oxygen Demand (C.O.D.), nitrates, phosphates and chlorides of municipal raw sewage and that of aeration tank and secondary clarifier of the Sewage Treatment Plant (STP), in relation to water at the treated sewage out-fall point, down-stream and up-stream of the Buckingham Canal at Kalpakkam were analyzed. Total Coliform and Faecal Coliform MPN counts were higher, 170 and 70/100 mL respectively in the raw sewage. However, the counts of the former in the aeration tank though remained similar, that of FC decreased to 50/100 mL; both of the counts further decreased to 30 and 44/100 mL respectively, in the secondary clarifier and were 110 and 23/100 mL, respectively at the treated sewage out-fall point in the canal. Total coliforms MPN was more than 18 times less in the water at the up-stream than that of the treated sewage out-fall point in the canal. Interestingly MPN of the FC in the up-stream water was nil while it was 8/100 mL in the canal's down-stream point. It is concluded that the FC, B.O.D., C.O.D., nitrates, phosphates and chlorides decreased and the D.O. increased in the treated-sewage due to the treatment of raw sewage through the STP.

Gastrointestinal health effects associated with the consumption of drinking water produced by point-of-use domestic reverse-osmosis filtration units.

PubMed Central

Payment, P; Franco, E; Richardson, L; Siemiatycki, J

1991-01-01

During a prospective epidemiological study of gastrointestinal health effects associated with the consumption of drinking water produced by reverse-osmosis domestic units, a correlation was demonstrated between the bacterial counts on R2A medium incubated at 35 degrees C and the reported gastrointestinal symptoms in families who used these units. A univariate correlation was found with bacterial counts on R2A medium at 20 degrees C but was confounded by the bacterial counts at 35 degrees C. Other variables, such as family size and amount of water consumed, were not independently explanatory of the rate of illness. These observations raise concerns for the possibility of increased disease associated with certain point-of-use treatment devices for domestic use when high levels of bacterial growth occur. PMID:2059052

Chi-squared and C statistic minimization for low count per bin data. [sampling in X ray astronomy

NASA Technical Reports Server (NTRS)

Nousek, John A.; Shue, David R.

1989-01-01

Results are presented from a computer simulation comparing two statistical fitting techniques on data samples with large and small counts per bin; the results are then related specifically to X-ray astronomy. The Marquardt and Powell minimization techniques are compared by using both to minimize the chi-squared statistic. In addition, Cash's C statistic is applied, with Powell's method, and it is shown that the C statistic produces better fits in the low-count regime than chi-squared.

Microbial quality of soft drinks served by the dispensing machines in fast food restaurants and convenience stores in Griffin, Georgia, and surrounding areas.

PubMed

Park, Yoen Ju; Chen, Jinru

2009-12-01

This study was undertaken to evaluate the microbial quality of the soft drinks served by fast food restaurants and gas station convenience stores in Griffin, GA, and surrounding areas. The soft drinks were collected from the dispensing machines in 8 fast food restaurants or gas station convenience stores in 2005 (n = 25) and in 10 fast food restaurants or gas station convenience stores in 2006 (n = 43) and 2007 (n = 43). One hundred milliliters of each soft drink was filtered through a hydrophobic grid membrane filter. The remaining portion of the soft drink was kept at room temperature for 4 h before sampling in order to mimic the possible holding time between purchase and consumption. The membrane filters were sampled for total aerobic bacteria, Enterobacteriaceae, lactic acid bacteria, and yeasts and molds. The microbial counts in the 2006 samples were numerically higher than the counts in the 2007 samples except for the average lactic acid bacteria counts, and were either significantly or numerically higher than the counts in the 2005 samples. Soft drinks sampled after the 4-h holding period had relatively higher counts than those sampled initially, with a few exceptions. Some soft drinks had over 4 log CFU/100 ml of total aerobic bacteria, Enterobacteriaceae, lactic acid bacteria, and yeast and mold cells. The study revealed the microbial quality of soft drinks served by dispensing machines in Griffin, GA, and surrounding areas, emphasizing the importance of effective sanitizing practice in retail settings.

Design and evaluation of a nondestructive fissile assay device for HTGR fuel samples

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

McNeany, S. R.; Knoll, R. W.; Jenkins, J. D.

1979-02-01

Nondestructive assay of fissile material plays an important role in nuclear fuel processing facilities. Information for product quality control, plant criticality safety, and nuclear materials accountability can be obtained from assay devices. All of this is necessary for a safe, efficient, and orderly operation of a production plant. Presented here is a design description and an operational evaluation of a device developed to nondestructively assay small samples of High-Temperature Gas-Cooled Reactor (HTGR) fuel. The measurement technique employed consists in thermal-neutron irradiation of a sample followed by pneumatic transfer to a high-efficiency neutron detector where delayed neutrons are counted. In general,more » samples undergo several irradiation and count cycles during a measurement. The total number of delayed-neutron counts accumulated is translated into grams of fissile mass through comparison with the counts accumulated in an identical irradiation and count sequence of calibration standards. Successful operation of the device through many experiments over a one-year period indicates high operational reliability. Tests of assay precision show this to be better than 0.25% for measurements of 10 min. Assay biases may be encountered if calibration standards are not representative of unknown samples, but reasonable care in construction and control of standards should lead to no more than 0.2% bias in the measurements. Nondestructive fissile assay of HTGR fuel samples by thermal-neutron irradiation and delayed-neutron detection has been demonstrated to be a rapid and accurate analysis technique. However, careful attention and control must be given to calibration standards to see that they remain representative of unknown samples.« less

Biodegradability of Chlorophenols in Surface Waters from the Urban Area of Buenos Aires.

PubMed

Gallego, A; Laurino Soulé, J; Napolitano, H; Rossi, S L; Vescina, C; Korol, S E

2018-04-01

Biodegradability of 2-Chlorophenol (2-CP), 3-Chlorophenol (3-CP), 4-Chlorophenol (4-CP), 2,4-Dichlorophenol (2,4-DCP) and 2,4,6 Trichlorophenol (2,4,6-TCP) has been tested in surface waters in the urban area of Buenos Aires. Samples were taken from the La Plata River and from the Reconquista and Matanza-Riachuelo basins, with a total amount of 18 sampling points. Water quality was established measuring chemical oxygen demand (COD), biochemical oxygen demand (BOD 5 ), and both Escherichia coli and Enterococcus counts. Biodegradability was carried out by a respirometric method, using a concentration of 20 mg L -1 of chlorophenol, and the surface water as inoculum. Chlorophenols concentration in the same water samples were simultaneously measured by a solid phase microextraction (SPME) procedure followed by gas chromatography-mass spectrometry (GC-MS). 2,4-DCP was the most degradable compound followed by 2,4,6-TCP, 4-CP, 3-CP and 2-CP. Biodegradability showed no correlation with compound concentration. At most sampling points the concentration was below the detection limit for all congeners. Biodegradability does not correlate even with COD, BOD 5 , or fecal contamination. Biodegradability assays highlighted information about bacterial exposure to contaminants that parameters routinely used for watercourse characterization do not reveal. For this reason, they might be a helpful tool to complete the characterization of a site.

50 CFR 679.7 - Prohibitions.

Code of Federal Regulations, 2012 CFR

2012-10-01

... collection of scientific data or biological samples from the salmon has been completed. (B) Non-Chinook... pollock CDQ in the BS before the observer has completed counting the salmon and collecting scientific data... count of salmon and the collection of scientific data or biological samples from the previous offload...

50 CFR 679.7 - Prohibitions.

Code of Federal Regulations, 2013 CFR

2013-10-01

... collection of scientific data or biological samples from the salmon has been completed. (B) Non-Chinook... pollock CDQ in the BS before the observer has completed counting the salmon and collecting scientific data... count of salmon and the collection of scientific data or biological samples from the previous offload...

Database crime to crime match rate calculation.

PubMed

Buckleton, John; Bright, Jo-Anne; Walsh, Simon J

2009-06-01

Guidance exists on how to count matches between samples in a crime sample database but we are unable to locate a definition of how to estimate a match rate. We propose a method that does not proceed from the match counting definition but which has a strong logic.

Probing the statistics of primordial fluctuations and their evolution

NASA Technical Reports Server (NTRS)

Gaztanaga, Enrique; Yokoyama, Jun'ichi

1993-01-01

The statistical distribution of fluctuations on various scales is analyzed in terms of the counts in cells of smoothed density fields, using volume-limited samples of galaxy redshift catalogs. It is shown that the distribution on large scales, with volume average of the two-point correlation function of the smoothed field less than about 0.05, is consistent with Gaussian. Statistics are shown to agree remarkably well with the negative binomial distribution, which has hierarchial correlations and a Gaussian behavior at large scales. If these observed properties correspond to the matter distribution, they suggest that our universe started with Gaussian fluctuations and evolved keeping hierarchial form.

A study of cellular counting to determine minimum thresholds for adequacy for liquid-based cervical cytology using a survey and counting protocol.

PubMed

Kitchener, Henry C; Gittins, Matthew; Desai, Mina; Smith, John H F; Cook, Gary; Roberts, Chris; Turnbull, Lesley

2015-03-01

Liquid-based cytology (LBC) for cervical screening would benefit from laboratory practice guidelines that define specimen adequacy for reporting of slides. The evidence base required to define cell adequacy should incorporate both ThinPrep™ (TP; Hologic, Inc., Bedford, MA, USA) and SurePath™ (SP; BD Diagnostics, Burlington, NC, USA), the two LBC systems used in the UK cervical screening programmes. The objectives of this study were to determine (1) current practice for reporting LBC in England, Wales and Scotland, (2) a reproducible method for cell counting, (3) the cellularity of slides classified as inadequate, negative or abnormal and (4) the impact of varying cellularity on the likelihood of detecting cytological abnormalities. The study involved four separate arms to pursue each of the four objectives. (1) A questionnaire survey of laboratories was conducted. (2) A standard counting protocol was developed and used by three experienced cytopathologists to determine a reliable and reproducible cell counting method. (3) Slide sets which included a range of cytological abnormalities were each sent to three laboratories for cell counting to study the correlation between cell counts and reported cytological outcomes. (4) Dilution of LBC samples by fluid only (unmixed) or by dilution with a sample containing normal cells (mixed) was performed to study the impact on reporting of reducing either the total cell count or the relative proportion of abnormal to normal cells. The study was conducted within the cervical screening programmes in England, Wales and Scotland, using routinely obtained cervical screening samples, and in 56 participating NHS cervical cytology laboratories. The study involved only routinely obtained cervical screening samples. There was no clinical intervention. The main outcome measures were (1) reliability of counting method, (2) correlation of reported cytology grades with cellularity and (3) levels of detection of abnormal cells in progressively diluted cervical samples. Laboratory practice varied in terms of threshold of cellular adequacy and of morphological markers of adequacy. While SP laboratories generally used a minimum acceptable cell count (MACC) of 15,000, the MACC employed by TP laboratories varied between 5000 and 15,000. The cell counting study showed that a standard protocol achieved moderate to strong inter-rater reproducibility. Analysis of slide reporting from laboratories revealed that a large proportion of the samples reported as inadequate had cell counts above a threshold of 15,000 for SP, and 5000 and 10,000 for TP. Inter-rater unanimity was greater among more cellular preparations. Dilution studies demonstrated greater detection of abnormalities in slides with counts above the MACC and among slides with more than 25 dyskaryotic cells. Variation in laboratory practice demonstrates a requirement for evidence-based standards for designating a MACC. This study has indicated that a MACC of 15,000 and 5000 for SP and TP, respectively, achieves a balance in terms of maintaining sensitivity and low inadequacy rates. The findings of this study should inform the development of laboratory practice guidelines. The National Institute for Health Research Health Technology Assessment programme.

Determining nest predators of the Least Bell's Vireo through point counts, tracking stations, and video photography

USGS Publications Warehouse

Peterson, Bonnie L.; Kus, Barbara E.; Deutschman, Douglas H.

2004-01-01

We compared three methods to determine nest predators of the Least Bell's Vireo (Vireo bellii pusillus) in San Diego County, California, during spring and summer 2000. Point counts and tracking stations were used to identify potential predators and video photography to document actual nest predators. Parental behavior at depredated nests was compared to that at successful nests to determine whether activity (frequency of trips to and from the nest) and singing vs. non-singing on the nest affected nest predation. Yellow-breasted Chats (Icteria virens) were the most abundant potential avian predator, followed by Western Scrub-Jays (Aphelocoma californica). Coyotes (Canis latrans) were abundant, with smaller mammalian predators occurring in low abundance. Cameras documented a 48% predation rate with scrub-jays as the major nest predators (67%), but Virginia opossums (Didelphis virginiana, 17%), gopher snakes (Pituophis melanoleucus, 8%) and Argentine ants (Linepithema humile, 8%) were also confirmed predators. Identification of potential predators from tracking stations and point counts demonstrated only moderate correspondence with actual nest predators. Parental behavior at the nest prior to depredation was not related to nest outcome.

An automated method of quantifying ferrite microstructures using electron backscatter diffraction (EBSD) data.

PubMed

Shrestha, Sachin L; Breen, Andrew J; Trimby, Patrick; Proust, Gwénaëlle; Ringer, Simon P; Cairney, Julie M

2014-02-01

The identification and quantification of the different ferrite microconstituents in steels has long been a major challenge for metallurgists. Manual point counting from images obtained by optical and scanning electron microscopy (SEM) is commonly used for this purpose. While classification systems exist, the complexity of steel microstructures means that identifying and quantifying these phases is still a great challenge. Moreover, point counting is extremely tedious, time consuming, and subject to operator bias. This paper presents a new automated identification and quantification technique for the characterisation of complex ferrite microstructures by electron backscatter diffraction (EBSD). This technique takes advantage of the fact that different classes of ferrite exhibit preferential grain boundary misorientations, aspect ratios and mean misorientation, all of which can be detected using current EBSD software. These characteristics are set as criteria for identification and linked to grain size to determine the area fractions. The results of this method were evaluated by comparing the new automated technique with point counting results. The technique could easily be applied to a range of other steel microstructures. © 2013 Published by Elsevier B.V.

Apheresis product identification in the transplant center: development of point-of-care protocols for extended blood typing of stem cell apheresis products.

PubMed

Cummerow, C; Schwind, P; Spicher, M; Spohn, G; Geisen, C; Seifried, E; Bönig, H

2012-06-01

Transfusion of the 'wrong' stem cell product would almost inevitably be lethal, yet assays to confirm the contents of the product bag, except by checking labels and paperwork, are lacking. To increase the likelihood that a product mix-up would be detected in the transplant center, we developed a simple protocol for extended blood typing and hence, for confirmation of donor/product identity, on a tube segment. Apheresis samples were applied, directly or after erythrocyte enrichment, to commercially available blood typing assays, including lateral flow cards and gel agglutination cards. Without sample modification, low hematocrit and high leukocyte count obviated definitive blood typing. Using the most simple erythrocyte enrichment protocol, that is, centrifugation, reliable blood group analysis became possible with either assay. Other, more cumbersome pre-analytical protocols were also successful but provided no advantage. The preferred method was validated on 100 samples; ABD was correctly identified in 100% of cases. Of the other Rh Ags, all except two 'small e', in both cases in heterozygous individuals, were detected; there were no false positives. A simple, inexpensive point-of-care assay for extended blood typing of apheresis products is available, which can reduce the fatal risk of administering the wrong stem cell product.

Automated thin-film analyses of hydrated interplanetary dust particles in the analytical electron microscope

NASA Technical Reports Server (NTRS)

Germani, M. S.; Bradley, J. P.; Brownlee, D. E.

1990-01-01

A 200 keV electron microscope was used to obtain elemental analyses from over 4000 points on thin sections of eight 'layer silicate' class interplanetary dust particles (IDPs). Major and minor element abundances from a volume approaching that of a cylinder 50 nm in diameter were observed. Mineral phases and their relative abundances in the thin sections were identified and petrographic characteristics were determined. Three of the particles contained smectite (1.0-1.2 nm basal spacing) and two contained serpentine (0.7 nm basal spacing). The point count analyses and Mg-Si-Fe ternary diagrams show that one of the serpentine-containing IDPs is similar to CI and CM chondritic meteorites. The IDPs exhibit evidence of aqueous processing, but they have typically experienced only short range, submicrometer scale alteration. The IDPs may provide a broad sampling of the asteroid belt.

Diversity and dynamics of antibiotic-resistant bacteria in cheese as determined by PCR denaturing gradient gel electrophoresis.

PubMed

Flórez, Ana Belén; Mayo, Baltasar

2015-12-02

This work reports the composition and succession of tetracycline- and erythromycin-resistant bacterial communities in a model cheese, monitored by polymerase chain reaction denaturing gradient gel electrophoresis (PCR-DGGE). Bacterial 16S rRNA genes were examined using this technique to detect structural changes in the cheese microbiota over manufacturing and ripening. Total bacterial genomic DNA, used as a template, was extracted from cultivable bacteria grown without and with tetracycline or erythromycin (both at 25 μg ml(-1)) on a non-selective medium used for enumeration of total and viable cells (Plate Count agar with Milk; PCA-M), and from those grown on selective and/or differential agar media used for counting various bacterial groups; i.e., lactic acid bacteria (de Man, Rogosa and Sharpe agar; MRSA), micrococci and staphylococci (Baird-Parker agar; BPA), and enterobacteria (Violet Red Bile Glucose agar; VRBGA). Large numbers of tetracycline- and erythromycin-resistant bacteria were detected in cheese samples at all stages of ripening. Counts of antibiotic-resistant bacteria varied widely depending on the microbial group and the point of sampling. In general, resistant bacteria were 0.5-1.0 Log10 units fewer in number than the corresponding susceptible bacteria. The PCR-DGGE profiles obtained with DNA isolated from the plates for total bacteria and the different bacterial groups suggested Escherichia coli, Lactococcus lactis, Enterococcus faecalis and Staphylococcus spp. as the microbial types resistant to both antibiotics tested. This study shows the suitability of the PCR-DGGE technique for rapidly identifying and tracking antibiotic resistant populations in cheese and, by extension, in other foods. Copyright © 2015 Elsevier B.V. All rights reserved.

Population Fisher information matrix and optimal design of discrete data responses in population pharmacodynamic experiments.

PubMed

Ogungbenro, Kayode; Aarons, Leon

2011-08-01

In the recent years, interest in the application of experimental design theory to population pharmacokinetic (PK) and pharmacodynamic (PD) experiments has increased. The aim is to improve the efficiency and the precision with which parameters are estimated during data analysis and sometimes to increase the power and reduce the sample size required for hypothesis testing. The population Fisher information matrix (PFIM) has been described for uniresponse and multiresponse population PK experiments for design evaluation and optimisation. Despite these developments and availability of tools for optimal design of population PK and PD experiments much of the effort has been focused on repeated continuous variable measurements with less work being done on repeated discrete type measurements. Discrete data arise mainly in PDs e.g. ordinal, nominal, dichotomous or count measurements. This paper implements expressions for the PFIM for repeated ordinal, dichotomous and count measurements based on analysis by a mixed-effects modelling technique. Three simulation studies were used to investigate the performance of the expressions. Example 1 is based on repeated dichotomous measurements, Example 2 is based on repeated count measurements and Example 3 is based on repeated ordinal measurements. Data simulated in MATLAB were analysed using NONMEM (Laplace method) and the glmmML package in R (Laplace and adaptive Gauss-Hermite quadrature methods). The results obtained for Examples 1 and 2 showed good agreement between the relative standard errors obtained using the PFIM and simulations. The results obtained for Example 3 showed the importance of sampling at the most informative time points. Implementation of these expressions will provide the opportunity for efficient design of population PD experiments that involve discrete type data through design evaluation and optimisation.

Estimating abundances of interacting species using morphological traits, foraging guilds, and habitat

USGS Publications Warehouse

Dorazio, Robert M.; Connor, Edward F.

2014-01-01

We developed a statistical model to estimate the abundances of potentially interacting species encountered while conducting point-count surveys at a set of ecologically relevant locations - as in a metacommunity of species. In the model we assume that abundances of species with similar traits (e.g., body size) are potentially correlated and that these correlations, when present, may exist among all species or only among functionally related species (such as members of the same foraging guild). We also assume that species-specific abundances vary among locations owing to systematic and stochastic sources of heterogeneity. For example, if abundances differ among locations due to differences in habitat, then measures of habitat may be included in the model as covariates. Naturally, the quantitative effects of these covariates are assumed to differ among species. Our model also accounts for the effects of detectability on the observed counts of each species. This aspect of the model is especially important for rare or uncommon species that may be difficult to detect in community-level surveys. Estimating the detectability of each species requires sampling locations to be surveyed repeatedly using different observers or different visits of a single observer. As an illustration, we fitted models to species-specific counts of birds obtained while sampling an avian community during the breeding season. In the analysis we examined whether species abundances appeared to be correlated due to similarities in morphological measures (body mass, beak length, tarsus length, wing length, tail length) and whether these correlations existed among all species or only among species of the same foraging guild. We also used the model to estimate the effects of forested area on species abundances and the effects of sound power output (as measured by body size) on species detection probabilities.

A brief update on physical and optical disector applications and sectioning-staining methods in neuroscience.

PubMed

Yurt, Kıymet Kübra; Kivrak, Elfide Gizem; Altun, Gamze; Mohamed, Hamza; Ali, Fathelrahman; Gasmalla, Hosam Eldeen; Kaplan, Suleyman

2018-02-26

A quantitative description of a three-dimensional (3D) object based on two-dimensional images can be made using stereological methods These methods involve unbiased approaches and provide reliable results with quantitative data. The quantitative morphology of the nervous system has been thoroughly researched in this context. In particular, various novel methods such as design-based stereological approaches have been applied in neuoromorphological studies. The main foundations of these methods are systematic random sampling and a 3D approach to structures such as tissues and organs. One key point in these methods is that selected samples should represent the entire structure. Quantification of neurons, i.e. particles, is important for revealing degrees of neurodegeneration and regeneration in an organ or system. One of the most crucial morphometric parameters in biological studies is thus the "number". The disector counting method introduced by Sterio in 1984 is an efficient and reliable solution for particle number estimation. In order to obtain precise results by means of stereological analysis, counting items should be seen clearly in the tissue. If an item in the tissue cannot be seen, these cannot be analyzed even using unbiased stereological techniques. Staining and sectioning processes therefore play a critical role in stereological analysis. The purpose of this review is to evaluate current neuroscientific studies using optical and physical disector counting methods and to discuss their definitions and methodological characteristics. Although the efficiency of the optical disector method in light microscopic studies has been revealed in recent years, the physical disector method is more easily performed in electron microscopic studies. Also, we offered to readers summaries of some common basic staining and sectioning methods, which can be used for stereological techniques in this review. Copyright © 2018 Elsevier B.V. All rights reserved.

Effectiveness of Surface Cleaning and Disinfection in a Brazilian Healthcare Facility

PubMed Central

Santos-Junior, Aires G.; Ferreira, Adriano M.; Frota, Oleci P.; Rigotti, Marcelo A.; Barcelos, Larissa da S.; Lopes de Sousa, Alvaro Francisco; de Andrade, Denise; Guerra, Odanir G.; R. Furlan, Mara C.

2018-01-01

Background: Failures in the processes of cleaning and disinfecting health service surfaces may result in the spread and transfer of pathogens that are often associated with healthcare-related infections and outbreaks. Aims: To assess the effectiveness of environmental surface cleaning and disinfection in a hospital clinic. Method: The study was conducted in a nursing ward with 45 beds. A total of 80 samples from five high-touch surfaces were evaluated before and after cleaning and disinfection, using the following methods: visual inspection, adenosine triphosphate bioluminescence assay, aerobic colony count, Staphylococcus aureus colony count, and evaluation of resistance to methicillin. The data analysis used nonparametric comparative and correlative tests to observe any differences in the pre- and post- cleaning and disinfection results for the surfaces assessed. Results: Effective cleaning and disinfection had a significant effect on only two surfaces when measured for the presence of adenosine triphosphate, the inner bathroom door handle (p=0.007) and the toilet bowl (p=0.01). When evaluated for Staphylococcus aureus colony count, the toilet flush handle also demonstrated a significant effect (p=0.04). Conclusion: The effectiveness of cleaning and disinfection of the surfaces tested was not satisfactory. An educational intervention is recommended for the cleaning and disinfection staff and the nursing team at the healthcare facility. Relevance to Clinical Practice: The data in the study revealed that daily hospital cleaning and disinfection in the sampled sites are not sufficient in medical and surgical wards. Hospital cleanliness must be reevaluated from the point of view of materials, such as an adequate supply of clean cloths, in addition to establishing more precise cleanliness protocols and accurate monitoring systems. PMID:29643951

Book review: Bird census techniques, Second edition

USGS Publications Warehouse

Sauer, John R.

2002-01-01

Conservation concerns, federal mandates to monitor birds, and citizen science programs have spawned a variety of surveys that collect information on bird populations. Unfortunately, all too frequently these surveys are poorly designed and use inappropriate counting methods. Some of the flawed approaches reflect a lack of understanding of statistical design; many ornithologists simply are not aware that many of our most entrenched counting methods (such as point counts) cannot appropriately be used in studies that compare densities of birds over space and time. It is likely that most of the readers of The Condor have participated in a bird population survey that has been criticized for poor sampling methods. For example, North American readers may be surprised to read in Bird Census Techniques that the North American Breeding Bird Survey 'is seriously flawed in its design,' and that 'Analysis of trends is impossible from points that are positioned along roads' (p. 109). Our conservation efforts are at risk if we do not acknowledge these concerns and improve our survey designs. Other surveys suffer from a lack of focus. In Bird Census Techniques, the authors emphasize that all surveys require clear statements of objectives and an understanding of appropriate survey designs to meet their objectives. Too often, we view survey design as the realm of ornithologists who know the life histories and logistical issues relevant to counting birds. This view reflects pure hubris: survey design is a collaboration between ornithologists, statisticians, and managers, in which goals based on management needs are met by applying statistical principles for design to the biological context of the species of interest. Poor survey design is often due to exclusion of some of these partners from survey development. Because ornithologists are too frequently unaware of these issues, books such as Bird Census Techniques take on added importance as manuals for educating ornithologists about the relevance of survey design and methods and the often subtle interdisciplinary nature of surveys.Review info: Bird Census Techniques, Second Edition. By Colin J. Bibby, Neil D. Burgess, David A. Hill, and Simon H. Mustoe. 2000. Academic Press, London, UK. xvii 1 302 pp.  ISBN 0- 12-095831-7.

Predicting fecal indicator organism contamination in Oregon coastal streams.

PubMed

Pettus, Paul; Foster, Eugene; Pan, Yangdong

2015-12-01

In this study, we used publicly available GIS layers and statistical tree-based modeling (CART and Random Forest) to predict pathogen indicator counts at a regional scale using 88 spatially explicit landscape predictors and 6657 samples from non-estuarine streams in the Oregon Coast Range. A total of 532 frequently sampled sites were parsed down to 93 pathogen sampling sites to control for spatial and temporal biases. This model's 56.5% explanation of variance, was comparable to other regional models, while still including a large number of variables. Analysis showed the most important predictors on bacteria counts to be: forest and natural riparian zones, cattle related activities, and urban land uses. This research confirmed linkages to anthropogenic activities, with the research prediction mapping showing increased bacteria counts in agricultural and urban land use areas and lower counts with more natural riparian conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microbiological, coliphages and physico-chemical assessments of the Umgeni River, South Africa.

PubMed

Singh, Atheesha; Lin, Johnson

2015-01-01

The water quality of Umgeni River in KwaZulu-Natal (South Africa) was investigated from April 2011 to January 2012. Indicator bacterial populations, physico-chemical properties, heavy metal contaminants and the presence of coliphages were determined according to standard protocols. The results showed that all sampling points failed to comply with the set guidelines for turbidity, total coliform, faecal coliform and total heterotrophic counts. Salmonella spp., Shigella spp. and Vibrio cholerae were also detected in all the water samples. The somatic coliphages and F-RNA coliphages were detected more frequently in the lower reaches of the river during summer. Temperature, electrical conductivity and pH were found to have positive relationships with the microbial communities especially in the lower catchment area during spring and summer indicating the impacts of various anthropogenic activities in the surrounding areas.

A sampling device for counting insect egg clusters and measuring vertical distribution of vegetation

Treesearch

Robert L. Talerico; Robert W., Jr. Wilson

1978-01-01

The use of a vertical sampling pole that delineates known volumes and position is illustrated and demonstrated for counting egg clusters of N. sertifer. The pole can also be used to estimate vertical and horizontal coverage, distribution or damage of vegetation or foliage.

Leukodepletion as a Point-of-Care Method for Monitoring HIV-1 Viral Load in Whole Blood

PubMed Central

Titchmarsh, Logan; Zeh, Clement; Verpoort, Thierry; Allain, Jean-Pierre

2014-01-01

In order to limit the interference of HIV-1 cellular nucleic acids in estimating viral load (VL), the feasibility of leukodepletion of a small whole-blood (WB) volume to eliminate only leukocyte cell content was investigated, using a selection of filters. The efficacy of leukocyte filtration was evaluated by counting, CD45 quantitative PCR, and HIV-1 DNA quantification. Plasma HIV-1 was tested by real-time reverse transcription (RT)-PCR. A specific, miniaturized filter was developed and tested for leukocyte and plasma virus retention, WB sample dilution, and filtration parameters in HIV-1-spiked WB samples. This device proved effective to retain >99.9% of white blood cells in 100 μl of WB without affecting plasma VL. The Samba sample preparation chemistry was adapted to use a leukodepleted WB sample for VL monitoring using the point-of-care Samba-1 semiautomated system. The clinical performance of the assay was evaluated by testing 207 consecutive venous EDTA WB samples from HIV-1-infected patients attending a CD4 testing clinic. Most patients were on antiretroviral treatment (ART), but their VL status was unknown. Compared to the Roche Cobas AmpliPrep/Cobas TaqMan HIV-1 test, the new Samba assay had a concordance of 96.5%. The use of the Samba system with a VL test for WB might contribute to HIV-1 ART management and reduce loss-to-follow-up rates in resource-limited settings. PMID:25428162

7 CFR 210.9 - Agreement with State agency.

Code of Federal Regulations, 2010 CFR

2010-01-01

... who are determined by the local educational agency to be eligible for such meals under 7 CFR part 245... authority official signing the claim shall be responsible for reviewing and analyzing meal counts to ensure... reimbursable meals served to eligible children at the point of service, or through another counting system if...

A critical evaluation of a flow cytometer used for detecting enterococci in recreational waters.

PubMed

King, Dawn N; Brenner, Kristen P; Rodgers, Mark R

2007-06-01

The current U. S. Environmental Protection Agency-approved method for enterococci (Method 1600) in recreational water is a membrane filter (MF) method that takes 24 hours to obtain results. If the recreational water is not in compliance with the standard, the risk of exposure to enteric pathogens may occur before the water is identified as hazardous. Because flow cytometry combined with specific fluorescent antibodies has the potential to be used as a rapid detection method for microorganisms, this technology was evaluated as a rapid, same-day method to detect enterococci in bathing beach waters. The flow cytometer chosen for this study was a laser microbial detection system designed to detect labeled antibodies. A comparison of MF counts with flow cytometry counts of enterococci in phosphate buffer and sterile-filtered recreational water showed good agreement between the two methods. However, when flow cytometry was used, the counts were several orders of magnitude higher than the MF counts with no correlation to Enterococcus spike concentrations. The unspiked sample controls frequently had higher counts than the samples spiked with enterococci. Particles within the spiked water samples were probably counted as target cells by the flow cytometer because of autofluorescence or non-specific adsorption of antibody and carryover to subsequent samples. For these reasons, this technology may not be suitable for enterococci detection in recreational waters. Improvements in research and instrument design that will eliminate high background and carryover may make this a viable technology in the

Evaluation of the automated hematology analyzer ADVIA® 120 for cerebrospinal fluid analysis and usage of unique hemolysis reagent.

PubMed

Tanada, H; Ikemoto, T; Masutani, R; Tanaka, H; Takubo, T

2014-02-01

In this study, we evaluated the performance of the ADVIA 120 hematology system for cerebrospinal fluid (CSF) assay. Cell counts and leukocyte differentials in CSF were examined with the ADVIA 120 hematology system, while simultaneously confirming an effective hemolysis agent for automated CSF cell counts. The detection limits of both white blood cell (WBC) counts and red blood cell (RBC) counts on the measurement of CSF cell counts by the ADVIA 120 hematology system were superior at 2 cells/μL (10(-6) L). The WBC count was linear up to 9.850 cells/μL, and the RBC count was linear up to approximately 20 000 cells/μL. The intrarun reproducibility indicated good precision. The leukocyte differential of CSF cells, performed by the ADVIA120 hematology system, showed good correlation with the microscopic procedure. The VersaLyse hemolysis solution efficiently lysed the samples without interfering with cell counts and leukocyte differential, even in a sample that included approximately 50 000/μL RBC. These data show the ADVIA 120 hematology system correctly measured the WBC count and leukocyte differential in CSF. The VersaLyse hemolysis solution is considered to be optimal for hemolysis treatment of CSF when measuring cell counts and differentials by the ADVIA 120 hematology system. © 2013 John Wiley & Sons Ltd.

Spatial variability in the pollen count in Sydney, Australia: can one sampling site accurately reflect the pollen count for a region?

PubMed

Katelaris, Constance H; Burke, Therese V; Byth, Karen

2004-08-01

There is increasing interest in the daily pollen count, with pollen-sensitive individuals using it to determine medication use and researchers relying on it for commencing clinical drug trials and assessing drug efficacy according to allergen exposure. Counts are often expressed qualitatively as low, medium, and high, and often only 1 pollen trap is used for an entire region. To examine the spatial variability in the pollen count in Sydney, Australia, and to compare discrepancies among low-, medium-, and high-count days at 3 sites separated by a maximum of 30 km. Three sites in western Sydney were sampled using Burkard traps. Data from the 3 sites were used to compare vegetation differences, possible effects of some meteorological parameters, and discrepancies among sites in low-, medium-, and high-count days. Total pollen counts during the spring months were 14,382 grains/m3 at Homebush, 11,584 grains/m3 at Eastern Creek, and 9,269 grains/m3 at Nepean. The only significant correlation between differences in meteorological parameters and differences in pollen counts was the Homebush-Nepean differences in rainfall and pollen counts. Comparison between low- and high-count days among the 3 sites revealed a discordance rate of 8% to 17%. For informing the public about pollen counts, the count from 1 trap is a reasonable estimation in a 30-km region; however, the discrepancies among 3 trap sites would have a significant impact on the performance of a clinical trial where enrollment was determined by a low or high count. Therefore, for clinical studies, data collection must be local and applicable to the study population.

Rapid classification of hairtail fish and pork freshness using an electronic nose based on the PCA method.

PubMed

Tian, Xiu-Ying; Cai, Qiang; Zhang, Yong-Ming

2012-01-01

We report a method for building a simple and reproducible electronic nose based on commercially available metal oxide sensors (MOS) to monitor the freshness of hairtail fish and pork stored at 15, 10, and 5 °C. After assembly in the laboratory, the proposed product was tested by a manufacturer. Sample delivery was based on the dynamic headspace method, and two features were extracted from the transient response of each sensor using an unsupervised principal component analysis (PCA) method. The compensation method and pattern recognition based on PCA are discussed in the current paper. PCA compensation can be used for all storage temperatures, however, pattern recognition differs according to storage conditions. Total volatile basic nitrogen (TVBN) and aerobic bacterial counts of the samples were measured simultaneously with the standard indicators of hairtail fish and pork freshness. The PCA models based on TVBN and aerobic bacterial counts were used to classify hairtail fish samples as "fresh" (TVBN ≤ 25 g and microbial counts ≤ 10(6) cfu/g) or "spoiled" (TVBN ≥ 25 g and microbial counts ≥ 10(6) cfu/g) and pork samples also as "fresh" (TVBN ≤ 15 g and microbial counts ≤ 10(6) cfu/g) or "spoiled" (TVBN ≥ 15 g and microbial counts ≥ 10(6) cfu/g). Good correlation coefficients between the responses of the electronic nose and the TVBN and aerobic bacterial counts of the samples were obtained. For hairtail fish, correlation coefficients were 0.97 and 0.91, and for pork, correlation coefficients were 0.81 and 0.88, respectively. Through laboratory simulation and field application, we were able to determine that the electronic nose could help ensure the shelf life of hairtail fish and pork, especially when an instrument is needed to take measurements rapidly. The results also showed that the electronic nose could analyze the process and level of spoilage for hairtail fish and pork.

Tumor infiltrating lymphocytes in triple negative breast cancer receiving neoadjuvant chemotherapy

PubMed Central

Castaneda, Carlos A; Mittendorf, Elizabeth; Casavilca, Sandro; Wu, Yun; Castillo, Miluska; Arboleda, Patricia; Nunez, Teresa; Guerra, Henry; Barrionuevo, Carlos; Dolores-Cerna, Ketty; Belmar-Lopez, Carolina; Abugattas, Julio; Calderon, Gabriela; De La Cruz, Miguel; Cotrina, Manuel; Dunstan, Jorge; Gomez, Henry L; Vidaurre, Tatiana

2016-01-01

AIM To determine influence of neoadjuvant-chemotherapy (NAC) over tumor-infiltrating-lymphocytes (TIL) in triple-negative-breast-cancer (TNBC). METHODS TILs were evaluated in 98 TNBC cases who came to Instituto Nacional de Enfermedades Neoplasicas from 2005 to 2010. Immunohistochemistry staining for CD3, CD4, CD8 and FOXP3 was performed in tissue microarrays (TMA) sections. Evaluation of H/E in full-face and immunohistochemistry in TMA sections was performed in pre and post-NAC samples. STATA software was used and P value < 0.05 was considered statistically significant. RESULTS Higher TIL evaluated in full-face sections from pre-NAC tumors was associated to pathologic-complete-response (pCR) (P = 0.0251) and outcome (P = 0.0334). TIL evaluated in TMA sections showed low level of agreement with full-face sections (ICC = 0.017-0.20) and was not associated to pCR or outcome. TIL in post-NAC samples were not associated to response or outcome. Post-NAC lesions with pCR had similar TIL levels than those without pCR (P = 0.6331). NAC produced a TIL decrease in full-face sections (P < 0.0001). Percentage of TIL subpopulations was correlated with their absolute counts. Higher counts of CD3, CD4, CD8 and FOXP3 in pre-NAC samples had longer disease-free-survival (DFS). Higher counts of CD3 in pre-NAC samples had longer overall-survival. Higher ratio of CD8/CD4 counts in pre-NAC was associated with pCR. Higher ratio of CD4/FOXP3 counts in pre-NAC was associated with longer DFS. Higher counts of CD4 in post-NAC samples were associated with pCR. CONCLUSION TIL in pre-NAC full-face sections in TNBC are correlated to longer survival. TIL in full-face differ from TMA sections, absolute count and percentage analysis of TIL subpopulation closely related. PMID:27777881

Comparison of bacteria populations in clean and recycled sand used for bedding in dairy facilities.

PubMed

Kristula, M A; Rogers, W; Hogan, J S; Sabo, M

2005-12-01

Bedding samples were collected twice from commercial dairy free-stall facilities that used recycled sand and clean sand in both the summer and winter. Collection began on the day sand was taken from the pile (d 0) and placed in the free stalls, and continued for 5 to 7 additional days. The number of colonies per gram of bedding of gram-negative bacteria, coliforms, Streptococcus spp., and Klebsiella spp. were estimated for each sand sample as well as amounts of dry and organic matter. Clean sand (CS) and recycled sand (RS) had the same bacterial counts when compared at any sampling time. The mean counts of bacterial populations did vary over the course of the study in both CS and RS. There was a significant increase in bacterial counts from d 0 to d 1 for gram-negative bacteria, coliforms, and Streptococcus spp. in both winter and summer. Counts of gram-negative bacteria, coliforms, Klebsiella spp., and Streptococcus spp. did not differ from d 1 to 7 in the winter. Total counts of gram-negative bacteria did not differ from d 1 to 7 in the summer. On d 1 in the summer, coliform counts were lower than at d 5 to 7, and Klebsiella spp. counts were lower than on d 3 to 7. Streptococcus spp. counts were high on d 1 and were constant through d 7 in both winter and summer trials. The number of coliform and Klebsiella spp. in both CS and RS was below the threshold thought to cause mastitis during the sampling times. The number of Streptococcus spp. was high in both CS and RS during the sampling periods. Other management factors need to be identified to decrease the number of Streptococcus spp. in bedding. Recycled sand had a higher organic matter and lower dry matter compared with CS in winter and summer. The results for this study were obtained from multiple herd comparisons, and herd was a significant effect suggesting that different management systems influence the number and types of bacteria in both CS and RS.

STATISTICS OF GAMMA-RAY POINT SOURCES BELOW THE FERMI DETECTION LIMIT

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

Malyshev, Dmitry; Hogg, David W., E-mail: dm137@nyu.edu

2011-09-10

An analytic relation between the statistics of photons in pixels and the number counts of multi-photon point sources is used to constrain the distribution of gamma-ray point sources below the Fermi detection limit at energies above 1 GeV and at latitudes below and above 30 deg. The derived source-count distribution is consistent with the distribution found by the Fermi Collaboration based on the first Fermi point-source catalog. In particular, we find that the contribution of resolved and unresolved active galactic nuclei (AGNs) to the total gamma-ray flux is below 20%-25%. In the best-fit model, the AGN-like point-source fraction is 17%more » {+-} 2%. Using the fact that the Galactic emission varies across the sky while the extragalactic diffuse emission is isotropic, we put a lower limit of 51% on Galactic diffuse emission and an upper limit of 32% on the contribution from extragalactic weak sources, such as star-forming galaxies. Possible systematic uncertainties are discussed.« less

Technical note: enumeration of mesophilic aerobes in milk: evaluation of standard official protocols and Petrifilm aerobic count plates.

PubMed

Freitas, R; Nero, L A; Carvalho, A F

2009-07-01

Enumeration of mesophilic aerobes (MA) is the main quality and hygiene parameter for raw and pasteurized milk. High levels of these microorganisms indicate poor conditions in production, storage, and processing of milk, and also the presence of pathogens. Fifteen raw and 15 pasteurized milk samples were submitted for MA enumeration by a conventional plating method (using plate count agar) and Petrifilm Aerobic Count plates (3M, St. Paul, MN), followed by incubation according to 3 official protocols: IDF/ISO (incubation at 30 degrees C for 72 h), American Public Health Association (32 degrees C for 48 h), and Brazilian Ministry of Agriculture (36 degrees C for 48 h). The results were compared by linear regression and ANOVA. Considering the results from conventional methodology, good correlation indices and absence of significant differences between mean counts were observed, independent of type of milk sample (raw or pasteurized) and incubation conditions (IDF/ISO, American Public Health Association, or Ministry of Agriculture). Considering the results from Petrifilm Aerobic Count plates, good correlation indices and absence of significant differences were only observed for raw milk samples. The microbiota of pasteurized milk interfered negatively with the performance of Petrifilm Aerobic Count plates, probably because of the presence of microorganisms that poorly reduce the dye indicator of this system.

Effect of a syringe aspiration technique versus a mechanical suction technique and use of N-butylscopolammonium bromide on the quantity and quality of bronchoalveolar lavage fluid samples obtained from horses with the summer pasture endophenotype of equine asthma.

PubMed

Bowser, Jacquelyn E; Costa, Lais R R; Rodil, Alba U; Lopp, Christine T; Johnson, Melanie E; Wills, Robert W; Swiderski, Cyprianna E

2018-03-01

OBJECTIVE To evaluate the effect of 2 bronchoalveolar lavage (BAL) sampling techniques and the use of N-butylscopolammonium bromide (NBB) on the quantity and quality of BAL fluid (BALF) samples obtained from horses with the summer pasture endophenotype of equine asthma. ANIMALS 8 horses with the summer pasture endophenotype of equine asthma. PROCEDURES BAL was performed bilaterally (right and left lung sites) with a flexible videoendoscope passed through the left or right nasal passage. During lavage of the first lung site, a BALF sample was collected by means of either gentle syringe aspiration or mechanical suction with a pressure-regulated wall-mounted suction pump. The endoscope was then maneuvered into the contralateral lung site, and lavage was performed with the alternate fluid retrieval technique. For each horse, BAL was performed bilaterally once with and once without premedication with NBB (21-day interval). The BALF samples retrieved were evaluated for volume, total cell count, differential cell count, RBC count, and total protein concentration. RESULTS Use of syringe aspiration significantly increased total BALF volume (mean volume increase, 40 mL [approx 7.5% yield]) and decreased total RBC count (mean decrease, 142 cells/μL), compared with use of mechanical suction. The BALF nucleated cell count and differential cell count did not differ between BAL procedures. Use of NBB had no effect on BALF retrieval. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that retrieval of BALF by syringe aspiration may increase yield and reduce barotrauma in horses at increased risk of bronchoconstriction and bronchiolar collapse. Further studies to determine the usefulness of NBB and other bronchodilators during BAL procedures in horses are warranted.

Dermatoglyphic features in patients with multiple sclerosis

PubMed Central

Sabanciogullari, Vedat; Cevik, Seyda; Karacan, Kezban; Bolayir, Ertugrul; Cimen, Mehmet

2014-01-01

Objective: To examine dermatoglyphic features to clarify implicated genetic predisposition in the etiology of multiple sclerosis (MS). Methods: The study was conducted between January and December 2013 in the Departments of Anatomy, and Neurology, Cumhuriyet University School of Medicine, Sivas, Turkey. The dermatoglyphic data of 61 patients, and a control group consisting of 62 healthy adults obtained with a digital scanner were transferred to a computer environment. The ImageJ program was used, and atd, dat, adt angles, a-b ridge count, sample types of all fingers, and ridge counts were calculated. Results: In both hands of the patients with MS, the a-b ridge count and ridge counts in all fingers increased, and the differences in these values were statistically significant. There was also a statistically significant increase in the dat angle in both hands of the MS patients. On the contrary, there was no statistically significant difference between the groups in terms of dermal ridge samples, and the most frequent sample in both groups was the ulnar loop. Conclusions: Aberrations in the distribution of dermatoglyphic samples support the genetic predisposition in MS etiology. Multiple sclerosis susceptible individuals may be determined by analyzing dermatoglyphic samples. PMID:25274586

The counting of native blood cells by digital microscopy

NASA Astrophysics Data System (ADS)

Torbin, S. O.; Doubrovski, V. A.; Zabenkov, I. V.; Tsareva, O. E.

2017-03-01

An algorithm for photographic images processing of blood samples in its native state was developed to determine the concentration of erythrocytes, leukocytes and platelets without individual separate preparation of cells' samples. Special "photo templates" were suggested to use in order to identify red blood cells. The effect of "highlighting" of leukocytes, which was found by authors, was used to increase the accuracy of this type of cells counting. Finally to raise the resolution of platelets from leukocytes the areas of their photo images were used, but not their sizes. It is shown that the accuracy of cells counting for native blood samples may be comparable with the accuracy of similar studies for smears. At the same time the proposed native blood analysis simplifies greatly the procedure of sample preparation in comparison to smear, permits to move from the detection of blood cells ratio to the determination of their concentrations in the sample.

Equivalency testing of TTC Tergitol 7 agar (ISO 9308-1:2000) with five culture media for the detection of E. coli in water samples in Greece.

PubMed

Mavridou, A; Smeti, E; Mandilara, G; Mandilara, G; Boufa, P; Vagiona-Arvanitidou, M; Vantarakis, A; Vassilandonopoulou, G; Pappa, O; Roussia, V; Tzouanopoulos, A; Livadara, M; Aisopou, I; Maraka, V; Nikolaou, E; Mandilara, G

2010-01-01

In this study ten laboratories in Greece compared the performance of reference method TTC Tergitol 7 Agar (with the additional test of beta-glucuronidase production) with five alternative methods, to detect E. coli in water, in line with European Water Directive recommendations. The samples were prepared by spiking drinking water with sewage effluent following a standard protocol. Chlorinated and non-chlorinated samples were used. The statistical analysis was based on the mean relative difference of confirmed counts and was performed in line with ISO 17994. The results showed that in total, three of the alternative methods (Chromocult Coliform agar, Membrane Lauryl Sulfate agar and Trypton Bilex-glucuronidase medium) were not different from TTC Tergitol 7 agar (TTC Tergitol 7 agar vs Chromocult Coliform agar, 294 samples, mean RD% 5.55; vs MLSA, 302 samples, mean RD% 1; vs TBX, 297 samples, mean RD% -2.78). The other two alternative methods (Membrane Faecal coliform medium and Colilert 18/ Quantitray) gave significantly higher counts than TTC Tergitol 7 agar (TTC Tergitol 7 agar vs MFc, 303 samples, mean RD% 8.81; vs Colilert-18/Quantitray, 76 samples, mean RD% 18.91). In other words, the alternative methods generated performance that was as reliable as, or even better than, the reference method. This study will help laboratories in Greece overcome culture and counting problems deriving from the EU reference method for E. coli counts in water samples.

[Analysis on 2011 quality control results on aerobic plate count of microbiology laboratories in China].

PubMed

Han, Haihong; Li, Ning; Li, Yepeng; Fu, Ping; Yu, Dongmin; Li Zhigang; Du, Chunming; Guo, Yunchang

2015-01-01

To test the aerobic plate count examining capability of microbiology laboratories, to ensure the accuracy and comparability of quantitative bacteria examination results, and to improve the quality of monitoring. The 4 different concentration aerobic plate count piece samples were prepared and noted as I, II, III and IV. After homogeneity and stability tests, the samples were delivered to monitoring institutions. The results of I, II, III samples were logarithmic transformed, and evaluated with Z-score method using the robust average and standard deviation. The results of IV samples were evaluated as "satisfactory" when reported as < 10 CFU/piece or as "not satisfactory" otherwise. Pearson χ2 test was used to analyze the ratio results. 309 monitoring institutions, which was 99.04% of the total number, reported their results. 271 institutions reported a satisfactory result, and the satisfactory rate was 87.70%. There was no statistical difference in satisfactory rates of I, II and III samples which were 81.52%, 88.30% and 91.40% respectively. The satisfactory rate of IV samples was 93.33%. There was no statistical difference in satisfactory rates between provincial and municipal CDC. The quality control program has provided scientific data that the aerobic plate count capability of the laboratories meets the requirements of monitoring tasks.

Wheat Ear Detection in Plots by Segmenting Mobile Laser Scanner Data

NASA Astrophysics Data System (ADS)

Velumani, K.; Oude Elberink, S.; Yang, M. Y.; Baret, F.

2017-09-01

The use of Light Detection and Ranging (LiDAR) to study agricultural crop traits is becoming popular. Wheat plant traits such as crop height, biomass fractions and plant population are of interest to agronomists and biologists for the assessment of a genotype's performance in the environment. Among these performance indicators, plant population in the field is still widely estimated through manual counting which is a tedious and labour intensive task. The goal of this study is to explore the suitability of LiDAR observations to automate the counting process by the individual detection of wheat ears in the agricultural field. However, this is a challenging task owing to the random cropping pattern and noisy returns present in the point cloud. The goal is achieved by first segmenting the 3D point cloud followed by the classification of segments into ears and non-ears. In this study, two segmentation techniques: a) voxel-based segmentation and b) mean shift segmentation were adapted to suit the segmentation of plant point clouds. An ear classification strategy was developed to distinguish the ear segments from leaves and stems. Finally, the ears extracted by the automatic methods were compared with reference ear segments prepared by manual segmentation. Both the methods had an average detection rate of 85 %, aggregated over different flowering stages. The voxel-based approach performed well for late flowering stages (wheat crops aged 210 days or more) with a mean percentage accuracy of 94 % and takes less than 20 seconds to process 50,000 points with an average point density of 16  points/cm2. Meanwhile, the mean shift approach showed comparatively better counting accuracy of 95% for early flowering stage (crops aged below 225 days) and takes approximately 4 minutes to process 50,000 points.

Improved Method for Determination of Respiring Individual Microorganisms in Natural Waters

PubMed Central

Tabor, Paul S.; Neihof, Rex A.

1982-01-01

A method is reported that combines the microscopic determinations of specific, individual, respiring microorganisms by the detection of electron transport system activity and the total number of organisms of an estuarine population by epifluorescence microscopy. An active cellular electron transport system specifically reduces 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride (INT) to INT-formazan, which is recognized as opaque intracellular deposits in microorganisms stained with acridine orange. In a comparison of previously described sample preparation techniques, a loss of >70% of the counts of INT-reducing microorganisms was shown to be due to the dissolution of INT-formazan deposits by immersion oil (used in microscopy). In addition, significantly fewer fluorescing microorganisms and INT-formazan deposits, both ≤0.2 μm in size, were found for sample preparations that included a Nuclepore filter. Visual clarity was enhanced, and significantly greater direct counts and counts of INT-reducing microorganisms were recognized by transferring microorganisms from a filter to a gelatin film on a cover glass, followed by coating the sample with additional gelatin to produce a transparent matrix. With this method, the number of INT-reducing microorganisms determined for a Chesapeake Bay water sample was 2-to 10-fold greater than the number of respiring organisms reported previously for marine or freshwater samples. INT-reducing microorganisms constituted 61% of the total direct counts determined for a Chesapeake Bay water sample. This is the highest percentage of metabolically active microorganisms of any aquatic population reported using a method which determines both total counts and specific activity. PMID:16346025

Improved method for determination of respiring individual microorganisms in natural waters.

PubMed

Tabor, P S; Neihof, R A

1982-06-01

A method is reported that combines the microscopic determinations of specific, individual, respiring microorganisms by the detection of electron transport system activity and the total number of organisms of an estuarine population by epifluorescence microscopy. An active cellular electron transport system specifically reduces 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride (INT) to INT-formazan, which is recognized as opaque intracellular deposits in microorganisms stained with acridine orange. In a comparison of previously described sample preparation techniques, a loss of >70% of the counts of INT-reducing microorganisms was shown to be due to the dissolution of INT-formazan deposits by immersion oil (used in microscopy). In addition, significantly fewer fluorescing microorganisms and INT-formazan deposits, both

Fortifying fresh human milk with commercial powdered human milk fortifiers does not affect bacterial growth during 6 hours at room temperature.

PubMed

Telang, Sucheta; Berseth, Carol Lynn; Ferguson, Paul W; Kinder, Julie M; DeRoin, Mark; Petschow, Bryon W

2005-10-01

To evaluate the growth of resident aerobic mesophilic flora and added Enterobacter sakazakii in fresh, unfortified human milk; fresh human milk fortified with two commercial powdered fortifiers differing in iron content; and infant formula prepared from powder. Eight mothers provided preterm breast milk samples. Breast milk samples were divided into three aliquots: unfortified, fortified with fortifier containing 1.44 mg iron/14 kcal, and fortified with fortifier containing 0.4 mg iron/14 kcal. Aliquots of formula were prepared. Breast milk and formula aliquots were divided into two test samples. Half were inoculated with low amounts of E sakazakii; half were not. All test samples were maintained at room temperature (22 degrees C), serially diluted, and plated onto agars after 0, 2, 4, and 6 hours. Plates were incubated at 35 degrees C and enumerated. Data were analyzed using repeated measures analysis of variance. P<.05 was considered significant. There were no differences in colony counts of aerobic bacteria among uninoculated or among inoculated human milk samples at any time; counts did not increase significantly over 6 hours. There were no differences in colony counts of E sakazakii among inoculated human milk samples at any time; counts did not increase significantly over 6 hours. Aerobic bacteria and E sakazakii colony counts from infant formula did not increase significantly over 6 hours. During 6 hours at 22 degrees C, fresh human milk and formula had negligible bacterial growth; fortifying human milk with powdered fortifiers did not affect bacterial growth.

Use of hot water for beef carcass decontamination.

PubMed

Castillo, A; Lucia, L M; Goodson, K J; Savell, J W; Acuff, G R

1998-01-01

Hot water treatment of beef carcass surfaces for reduction of Escherichia coli O157:H7, Salmonella typhimurium, and various indicator organisms was studied using a model carcass spray cabinet. Paired hot carcass surface regions with different external fat characteristics (inside round, outside round, brisket, flank, and clod) were removed from carcasses immediately after the slaughter and dressing process. All cuts were inoculated with bovine feces containing 10(6)/g each of rifampicin-resistant E. coli O157:H7 and S. typhimurium, or with uninoculated bovine feces. Surfaces then were exposed to a carcass water wash or a water wash followed by hot water spray (95 degrees C). Counts of rifampicin-resistant Salmonella and E. coli or aerobic plate count (APC) and coliform counts were conducted before and after each treatment. All treatments significantly reduced levels of pathogens from the initial inoculation level of 5.0 log(10) CFU/cm2. Treatments including hot water sprays provided mean reductions of initial counts for E. coli O157:H7 and S. typhimurium of 3.7 and 3.8 log, APC reductions of 2.9 log, and coliform and thermotolerant coliform count reductions of 3.3 log. The efficacy of hot water treatments was affected by the carcass surface region, but not by delaying the treatment (30 min) after contaminating the surface. Verification of efficacy of hot water interventions used as critical control points in a hazard analysis critical control point (HACCP) system may be possible using coliform counts.

Identification of CSF fistulas by radionuclide counting

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

Yamamoto, Y.; Kunishio, K.; Sunami, N.

1990-07-01

A radionuclide counting method, performed with the patient prone and the neck flexed, was used successfully to diagnose CSF rhinorrhea in two patients. A normal radionuclide ratio (radionuclide counts in pledget/radionuclide counts in 1-ml blood sample) was obtained in 11 normal control subjects. Significance was determined to be a ratio greater than 0.37. Use of radionuclide counting method of determining CSF rhinorrhea is recommended when other methods have failed to locate a site of leakage or when posttraumatic meningitis suggests subclinical CSF rhinorrhea.

A systematic assessment of goblet cell sampling of the bulbar conjunctiva by impression cytology.

PubMed

Doughty, Michael J

2015-07-01

The purpose of this study was to assess the apparent goblet cell density (GCD) from conjunctival impression cytology (CIC) samples in relation to the number of conjunctival cells collected onto the filters. CIC specimens were collected from the superior-temporal bulbar conjunctiva of 16 pigmented rabbits onto Biopore (Millicell-CM) membranes, fixed with buffered glutaraldehyde and stained with Giemsa. Different numbers of microscope fields of view in each of the specimens were imaged by light microscopy using a 20× magnification objective lens (200× final magnification), and the goblet cells marked and counted. The GCD values/sq. mm were calculated. The same conjunctival region of 3 other rabbits was also prepared for transmission electron microscopy (TEM) by fixation, in situ, with the same buffered glutaraldehyde. Mean values for GCD estimates were found to vary from 399 to 1576 cells/sq. mm, depending on the image sampling and analysis strategy chosen, with the lowest inter-sample variance of around 10% being found if a maximum goblet cell count was taken on substantially multilayered regions of the CIC specimens. Counts of the number of goblet cells per 1000 visible conjunctival epithelial cells yielded a value of close to 90 (range 36-151), with modest inter-sample variability of around 30%. A three or ten 200× microscope field and random sampling strategy yielded mean GCD values between 542 and 670 cells/sq. mm, but with very high intra- and inter-sample variance of at least 60% and sometimes higher than 100%. TEM confirmed the multilayered organization of the conjunctiva and the deeper lying goblet cells. The general use of a goblet cell count as an objective marker for conjunctival normality or health is likely to be highly variable unless a more specific strategy is adopted. Beyond providing details of exactly the counting strategy used, it would be very useful to provide full details of the actual microscope field size used as well as information on the intra-sample variability in goblet cell counts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of nonpoint-source contamination, Wisconsin: Selected data for 1992 water year

USGS Publications Warehouse

Graczyk, D.J.; Walker, J.F.; Greb, S.R.; Corsi, Steven R.; Owens, D.W.

1993-01-01

This report presents the annual results of the U.S. Geological Survey's (USGS) watershed-management evaluation monitoring program in Wisconsin. The overall objective of each individual project in the program is to determine if the water chemistry in the receiving stream has changed as a result of the implementation of land-management practices in the watershed. This is accomplished through monitoring of water chemistry and ancillary variables before best-management practices (BMP's) are installed ('pre-BMP'), during installation ('transitional'), and after ('post-BMP') watershed- management plans have been completely implemented. Fecal-coliform (FC) counts ranged between 10 and 310,00/100 mL. A large range of values occurred within duplicate and triplicate samples as well as over time. The median percentage difference between duplicate and triplicate samples was 17 percent although 4 out of the total 60 duplicate and triplicate samples had differences greater than 100 percent. A decrease in FC counts generally occurred over the duration of the 4-day analyses. Linear regression models of the log-concentration values (dependent variable) with respect to time (independent variable) were calculated for all samples. Negative slopes were found for 14 of the 15 samples. Slopes varied from +0.5 to -38.4 percent gain/loss/day, with a median slope of -8.5 percent/day. A t-test was applied to the data to examine whether or not significant differences in FC counts exist with respect to holding times. Because the T-test only compares two treatments, the test was conducted 3 times (0 versus 24-hr holding time, 0 versus 48-hr holding time, and 0 versus 72-hr holding time). Setting the level of significance at p less than 0.05 and assuming equal variances, 27 percent (all from Bower and Otter Creeks) of the samples demonstrated a significant difference in colony count over the first 24 hr, 40 percent over 48 hr, and 47 percent over 72 hr. All samples that exhibited a significant change in colony count were because of a decrease in colony count of the sample.

EVALUATING PROBABILITY SAMPLING STRATEGIES FOR ESTIMATING REDD COUNTS: AN EXAMPLE WITH CHINOOK SALMON (Oncorhynchus tshawytscha)

EPA Science Inventory

Precise, unbiased estimates of population size are an essential tool for fisheries management. For a wide variety of salmonid fishes, redd counts from a sample of reaches are commonly used to monitor annual trends in abundance. Using a 9-year time series of georeferenced censuses...

Direct quantification and distribution of tetracycline-resistant genes in meat samples by real-time polymerase chain reaction.

PubMed

Guarddon, Mónica; Miranda, Jose M; Vázquez, Beatriz I; Cepeda, Alberto; Franco, Carlos M

2012-07-01

The evolution of antimicrobial-resistant bacteria has become a threat to food safety and methods to control them are necessary. Counts of tetracycline-resistant (TR) bacteria by microbiological methods were compared with those obtained by quantitative PCR (qPCR) in 80 meat samples. TR Enterobacteriaceae counts were similar between the count plate method and qPCR (P= 0.24), whereas TR aerobic mesophilic bacteria counts were significantly higher by the microbiological method (P < 0.001). The distribution of tetA and tetB genes was investigated in different types of meat. tetA was detected in chicken meat (40%), turkey meat (100%), pork (20%), and beef (40%) samples, whereas tetB was detected in chicken meat (45%), turkey meat (70%), pork (30%), and beef (35%) samples. The presence of tetracycline residues was also investigated by a receptor assay. This study offers an alternative and rapid method for monitoring the presence of TR bacteria in meat and furthers the understanding of the distribution of tetA and tetB genes. © 2012 Institute of Food Technologists®

Measuring larval nematode contamination on cattle pastures: Comparing two herbage sampling methods.

PubMed

Verschave, S H; Levecke, B; Duchateau, L; Vercruysse, J; Charlier, J

2015-06-15

Assessing levels of pasture larval contamination is frequently used to study the population dynamics of the free-living stages of parasitic nematodes of livestock. Direct quantification of infective larvae (L3) on herbage is the most applied method to measure pasture larval contamination. However, herbage collection remains labour intensive and there is a lack of studies addressing the variation induced by the sampling method and the required sample size. The aim of this study was (1) to compare two different sampling methods in terms of pasture larval count results and time required to sample, (2) to assess the amount of variation in larval counts at the level of sample plot, pasture and season, respectively and (3) to calculate the required sample size to assess pasture larval contamination with a predefined precision using random plots across pasture. Eight young stock pastures of different commercial dairy herds were sampled in three consecutive seasons during the grazing season (spring, summer and autumn). On each pasture, herbage samples were collected through both a double-crossed W-transect with samples taken every 10 steps (method 1) and four random located plots of 0.16 m(2) with collection of all herbage within the plot (method 2). The average (± standard deviation (SD)) pasture larval contamination using sampling methods 1 and 2 was 325 (± 479) and 305 (± 444)L3/kg dry herbage (DH), respectively. Large discrepancies in pasture larval counts of the same pasture and season were often seen between methods, but no significant difference (P = 0.38) in larval counts between methods was found. Less time was required to collect samples with method 2. This difference in collection time between methods was most pronounced for pastures with a surface area larger than 1 ha. The variation in pasture larval counts from samples generated by random plot sampling was mainly due to the repeated measurements on the same pasture in the same season (residual variance component = 6.2), rather than due to pasture (variance component = 0.55) or season (variance component = 0.15). Using the observed distribution of L3, the required sample size (i.e. number of plots per pasture) for sampling a pasture through random plots with a particular precision was simulated. A higher relative precision was acquired when estimating PLC on pastures with a high larval contamination and a low level of aggregation compared to pastures with a low larval contamination when the same sample size was applied. In the future, herbage sampling through random plots across pasture (method 2) seems a promising method to develop further as no significant difference in counts between the methods was found and this method was less time consuming. Copyright © 2015 Elsevier B.V. All rights reserved.

Dying dyons don't count

NASA Astrophysics Data System (ADS)

Cheng, Miranda C. N.; Verlinde, Erik P.

2007-09-01

The dyonic 1/4-BPS states in 4D string theory with Script N = 4 spacetime supersymmetry are counted by a Siegel modular form. The pole structure of the modular form leads to a contour dependence in the counting formula obscuring its duality invariance. We exhibit the relation between this ambiguity and the (dis-)appearance of bound states of 1/2-BPS configurations. Using this insight we propose a precise moduli-dependent contour prescription for the counting formula. We then show that the degeneracies are duality-invariant and are correctly adjusted at the walls of marginal stability to account for the (dis-)appearance of the two-centered bound states. Especially, for large black holes none of these bound states exists at the attractor point and none of these ambiguous poles contributes to the counting formula. Using this fact we also propose a second, moduli-independent contour which counts the ``immortal dyons" that are stable everywhere.

Estimation of Traffic Variables Using Point Processing Techniques

DOT National Transportation Integrated Search

1978-05-01

An alternative approach to estimating aggregate traffic variables on freeways--spatial mean velocity and density--is presented. Vehicle arrival times at a given location on a roadway, typically a presence detector, are regarded as a point or counting...

Microbiological quality of pastrami and associated surfaces at the point of sale in Kayseri, Turkey.

PubMed

Yildirim, Y; Ertas Onmaz, N; Gonulalan, Z; Al, S; Yildirim, A; Karadal, F; Hizlisoy, H; Pamuk, Ş

2017-05-01

The aim of this study is to trace the possible relations between the hygienic status of slicing utensils and the microbiological quality of pastrami. A total of 75 pastrami retail markets were visited in Kayseri, Turkey, where the pastrami (a ready-to-eat meat product) is commonly produced and consumed. Sliced pastrami, the cutting board and knife surface swabs were collected from each pastrami retail point to trace possible sources of contamination. Samples were analysed for the presence of total viable counts (TVC), total coliforms, Escherichia coli, members of Enterobacteriaceae, Staphylococcus aureus and Listeria spp. In addition, pastrami samples were analysed for sulphite-reducing Clostridium spp. and Toxoplasma gondii. When compared with the target values of related literatures, a total of 6 (8%) pastrami samples were found unsatisfactory as a result of TVC (5.3%), Enterobacteriaceae (5.3%), E. coli (2.6%), S. aureus (2.6%), Listeria spp. (2.6%) and Listeria monocytogenes (1.3%) contaminations. No T. gondii positivity was observed among the pastrami samples. None of the cutting board and knife surface swabs were found to harbour TVC level >10 3  cfu/cm 2 , E. coli and L. monocytogenes. For the total coliforms, 7 (9.3%) and 5 (6.6%) of cutting board and knife surface swabs were found to exceed the target value (<2.5 cfu/cm 2 ), respectively. No statistically significant correlation was detected between the organisms on pastrami and slicing utensils indicating that pastrami were not cross-contaminated by the contact surfaces. More emphasis needs to be placed for training of food handlers and to apply good hygienic practices at the point of pastrami sale. The conditions at retail points must be monitored and inspections should be tightened to protect public health. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

A COMPARISON OF GALAXY COUNTING TECHNIQUES IN SPECTROSCOPICALLY UNDERSAMPLED REGIONS

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

Specian, Mike A.; Szalay, Alex S., E-mail: mspecia1@jhu.edu, E-mail: szalay@jhu.edu

2016-11-01

Accurate measures of galactic overdensities are invaluable for precision cosmology. Obtaining these measurements is complicated when members of one’s galaxy sample lack radial depths, most commonly derived via spectroscopic redshifts. In this paper, we utilize the Sloan Digital Sky Survey’s Main Galaxy Sample to compare seven methods of counting galaxies in cells when many of those galaxies lack redshifts. These methods fall into three categories: assigning galaxies discrete redshifts, scaling the numbers counted using regions’ spectroscopic completeness properties, and employing probabilistic techniques. We split spectroscopically undersampled regions into three types—those inside the spectroscopic footprint, those outside but adjacent to it,more » and those distant from it. Through Monte Carlo simulations, we demonstrate that the preferred counting techniques are a function of region type, cell size, and redshift. We conclude by reporting optimal counting strategies under a variety of conditions.« less

Estimating occupancy and abundance using aerial images with imperfect detection

USGS Publications Warehouse

Williams, Perry J.; Hooten, Mevin B.; Womble, Jamie N.; Bower, Michael R.

2017-01-01

Species distribution and abundance are critical population characteristics for efficient management, conservation, and ecological insight. Point process models are a powerful tool for modelling distribution and abundance, and can incorporate many data types, including count data, presence-absence data, and presence-only data. Aerial photographic images are a natural tool for collecting data to fit point process models, but aerial images do not always capture all animals that are present at a site. Methods for estimating detection probability for aerial surveys usually include collecting auxiliary data to estimate the proportion of time animals are available to be detected.We developed an approach for fitting point process models using an N-mixture model framework to estimate detection probability for aerial occupancy and abundance surveys. Our method uses multiple aerial images taken of animals at the same spatial location to provide temporal replication of sample sites. The intersection of the images provide multiple counts of individuals at different times. We examined this approach using both simulated and real data of sea otters (Enhydra lutris kenyoni) in Glacier Bay National Park, southeastern Alaska.Using our proposed methods, we estimated detection probability of sea otters to be 0.76, the same as visual aerial surveys that have been used in the past. Further, simulations demonstrated that our approach is a promising tool for estimating occupancy, abundance, and detection probability from aerial photographic surveys.Our methods can be readily extended to data collected using unmanned aerial vehicles, as technology and regulations permit. The generality of our methods for other aerial surveys depends on how well surveys can be designed to meet the assumptions of N-mixture models.

The immunological response of HIV-positive patients initiating HAART at the Komfo Anokye Teaching Hospital, Kumasi, Ghana.

PubMed

Annison, L; Dompreh, A; Adu-Sarkodie, Y

2013-12-01

The study sought to document the experience of immunological improvement among Ghanaian PLHIV on HAART comparing different categories of patients. Serology Unit, Komfo Anokye Teaching Hospital, Kumasi, Ghana. The study comprised a convenient sample of 303 treatment naïve HIV patients due to start HAART. Questionnaires were used to collect patient demographic and clinical data. Four CD4 counts were measured at six-monthly intervals to determine rates of CD4 change. These were pre-therapy, 1(st) post-therapy, 2(nd) post-therapy, and 3(rd) post-therapy counts. The rates of CD4 change among the different categories of patients were also compared. At baseline, women had higher CD4 count (mean of 77.4 cells/μl), and mean age of participants was 40 years. The CD4 count increased from a mean baseline of 70.2 cells/μl to 229.2, 270.0, and 297.6 cells/μl at 6, 12, and 18 months of treatment respectively (P < 0.0001 at each time point). There were no gender (P=0.46) and age (P=0.96) differences in treatment response. There was no difference (P=0.18) in treatment response comparing those with CD4 <250 cells/μl and those whose CD4 count was between 250 and 350 cells/μl at baseline although patients with baseline CD4 count <250 cells/μl showed larger increases after 12 months of treatment. Out of 282 patients with pre-therapy CD4 count ≤250 cells/μl, 241 (85.5%) and 41 (14.5%) were adherents and nonadherents respectively. Mean rate of increase was 15.2 and 8.4 cells/μl/month in adherent and non-adherent patients respectively (p=0.2). The study suggests that a sustained CD4 increase could be achieved in adherent patients commencing therapy with baseline CD4 count ≤250 cells/μl, and that these patients have greater ability for immunological recovery during 12 months of treatment The study, therefore, concludes that significant immunological improvement is possible among Ghanaian PLHIV on HAART as long as a high level of treatment adherence is observed.

High spatial resolution detection of low-energy electrons using an event-counting method, application to point projection microscopy

NASA Astrophysics Data System (ADS)

Salançon, Evelyne; Degiovanni, Alain; Lapena, Laurent; Morin, Roger

2018-04-01

An event-counting method using a two-microchannel plate stack in a low-energy electron point projection microscope is implemented. 15 μm detector spatial resolution, i.e., the distance between first-neighbor microchannels, is demonstrated. This leads to a 7 times better microscope resolution. Compared to previous work with neutrons [Tremsin et al., Nucl. Instrum. Methods Phys. Res., Sect. A 592, 374 (2008)], the large number of detection events achieved with electrons shows that the local response of the detector is mainly governed by the angle between the hexagonal structures of the two microchannel plates. Using this method in point projection microscopy offers the prospect of working with a greater source-object distance (350 nm instead of 50 nm), advancing toward atomic resolution.

A Novel In-Beam Delayed Neutron Counting Technique for Characterization of Special Nuclear Materials

NASA Astrophysics Data System (ADS)

Bentoumi, G.; Rogge, R. B.; Andrews, M. T.; Corcoran, E. C.; Dimayuga, I.; Kelly, D. G.; Li, L.; Sur, B.

2016-12-01

A delayed neutron counting (DNC) system, where the sample to be analyzed remains stationary in a thermal neutron beam outside of the reactor, has been developed at the National Research Universal (NRU) reactor of the Canadian Nuclear Laboratories (CNL) at Chalk River. The new in-beam DNC is a novel approach for non-destructive characterization of special nuclear materials (SNM) that could enable identification and quantification of fissile isotopes within a large and shielded sample. Despite the orders of magnitude reduction in neutron flux, the in-beam DNC method can be as informative as the conventional in-core DNC for most cases while offering practical advantages and mitigated risk when dealing with large radioactive samples of unknown origin. This paper addresses (1) the qualification of in-beam DNC using a monochromatic thermal neutron beam in conjunction with a proven counting apparatus designed originally for in-core DNC, and (2) application of in-beam DNC to an examination of large sealed capsules containing unknown radioactive materials. Initial results showed that the in-beam DNC setup permits non-destructive analysis of bulky and gamma shielded samples. The method does not lend itself to trace analysis, and at best could only reveal the presence of a few milligrams of 235U via the assay of in-beam DNC total counts. Through analysis of DNC count rates, the technique could be used in combination with other neutron or gamma techniques to quantify isotopes present within samples.

Total and Viable Legionella pneumophila Cells in Hot and Natural Waters as Measured by Immunofluorescence-Based Assays and Solid-Phase Cytometry ▿†

PubMed Central

Parthuisot, N.; Binet, M.; Touron-Bodilis, A.; Pougnard, C.; Lebaron, P.; Baudart, J.

2011-01-01

A new method was developed for the rapid and sensitive detection of viable Legionella pneumophila. The method combines specific immunofluorescence (IF) staining using monoclonal antibodies with a bacterial viability marker (ChemChrome V6 cellular esterase activity marker) by means of solid-phase cytometry (SPC). IF methods were applied to the detection and enumeration of both the total and viable L. pneumophila cells in water samples. The sensitivity of the IF methods coupled to SPC was 34 cells liter−1, and the reproducibility was good, with the coefficient of variation generally falling below 30%. IF methods were applied to the enumeration of total and viable L. pneumophila cells in 46 domestic hot water samples as well as in cooling tower water and natural water samples, such as thermal spring water and freshwater samples. Comparison with standard plate counts showed that (i) the total direct counts were always higher than the plate counts and (ii) the viable counts were higher than or close to the plate counts. With domestic hot waters, when the IF assay was combined with the viability test, SPC detected up to 3.4 × 103 viable but nonculturable L. pneumophila cells per liter. These direct IF methods could be a powerful tool for high-frequency monitoring of domestic hot waters or for investigating the occurrence of viable L. pneumophila in both man-made water systems and environmental water samples. PMID:21742913

Plutonium and uranium determination in environmental samples: combined solvent extraction-liquid scintillation method.

PubMed

McDowell, W J; Farrar, D T; Billings, M R

1974-12-01

A method for the determination of uranium and plutonium by a combined high-resolution liquid scintillation-solvent extraction method is presented. Assuming a sample count equal to background count to be the detection limit, the lower detection limit for these and other alpha-emitting nuclides is 1.0 dpm with a Pyrex sample tube, 0.3 dpm with a quartz sample tube using present detector shielding or 0.02 d.p.m. with pulse-shape discrimination. Alpha-counting efficiency is 100%. With the counting data presented as an alpha-energy spectrum, an energy resolution of 0.2-0.3 MeV peak half-width and an energy identification to +/-0.1 MeV are possible. Thus, within these limits, identification and quantitative determination of a specific alpha-emitter, independent of chemical separation, are possible. The separation procedure allows greater than 98% recovery of uranium and plutonium from solution containing large amounts of iron and other interfering substances. In most cases uranium, even when present in 10(8)-fold molar ratio, may be quantitatively separated from plutonium without loss of the plutonium. Potential applications of this general analytical concept to other alpha-counting problems are noted. Special problems associated with the determination of plutonium in soil and water samples are discussed. Results of tests to determine the pulse-height and energy-resolution characteristics of several scintillators are presented. Construction of the high-resolution liquid scintillation detector is described.

The INCA-Pathogens model: An application to the Loimijoki River basin in Finland.

PubMed

Rankinen, K; Butterfield, D; Faneca Sànchez, M; Grizzetti, B; Whitehead, P; Pitkänen, T; Uusi-Kämppä, J; Leckie, H

2016-12-01

Good hygienic quality of surface waters is essential for drinking water production, irrigation of crops and recreation. Predictions of how and when microbes are transported by rivers are needed to protect downstream water users. In this study we tested the new process-based INCA-Pathogens model in the agricultural Loimijoki River basin (3138km 2 ) in Finland, and we quantified ecosystem services of water purification and water provisioning for drinking and recreation purposes under different scenarios. INCA is a catchment scale process based model to calculate pollutant transfer from terrestrial environment and point sources to the catchment outlet. A clear gradient was observed in the numbers of faecal coliforms along the River Loimijoki. The highest bacterial counts were detected in the middle part of the main stream immediately after small industries and municipal sewage treatment plants. In terms of model performance, the INCA-Pathogen model was able to produce faecal coliform counts and seasonality both in the low pollution level sampling points and in the high pollution level sampling points. The model was sensitive to the parameters defining light decay in river water and in soil compartment, as well as to the amount of faecal coliforms in the manure spread on the fields. The modeling results showed that the number of faecal coliforms repeatedly exceeded 1000 bacteria 100ml -1 . Moreover, results lead to the following conclusions: 1) Climate change does not cause a major threat to hygienic water quality as higher precipitation increases runoff and causes diluting effect in the river, 2) Intensification of agriculture is not a threat as long as animal density remains relatively low and environmental legislation is followed, 3) More intensive agriculture without environmental legislation causes a threat especially in tributaries with high field percentage and animal density, and 4) Hygienic water quality in the River Loimijoki can best be improved by improving sewage treatment. We conclude that this catchment scale model is a useful tool for addressing catchment management and water treatment planning issues. Copyright © 2016 Elsevier B.V. All rights reserved.

On the box-counting dimension of the potential singular set for suitable weak solutions to the 3D Navier-Stokes equations

NASA Astrophysics Data System (ADS)

Wang, Yanqing; Wu, Gang

2017-05-01

In this paper, we are concerned with the upper box-counting dimension of the set of possible singular points in the space-time of suitable weak solutions to the 3D Navier-Stokes equations. By taking full advantage of the pressure \\Pi in terms of \

National Survey: What Do Principals Believe? Technology Counts, 2018. Education Week. Volume 37, Issue 27

ERIC Educational Resources Information Center

Bushweller, Kevin C., Ed.

2018-01-01

The 2018 edition of "Technology Counts" is a nationally representative survey of 500 principals, assistant principals, and other school leaders to better understand what principals are thinking and doing about some of the technology issues in their schools today. Contents include: (1) Pressure Points for Principals (Kevin Bushweller);…

Parental Involvement: What Counts, Who Counts It, and Does It Help?

ERIC Educational Resources Information Center

Flessa, Joseph

2008-01-01

When asked to explain why so many urban schools show unsatisfactory results on academic or social measures, principals routinely and quickly turn to descriptions of parents. In other words, when seeking to explain why work within a school is so difficult or why reform initiatives have been unsuccessful, many principals point outside the school.…

Electronic strain-level counter

NASA Technical Reports Server (NTRS)

Pitts, F. L.; Spencer, J. L. (Inventor)

1973-01-01

An electronic strain level counter for obtaining structural strain data on in-flight aircraft is described. The device counts the number of times the strain at a point on an aircraft structural member exceeds each of several preset levels. A dead band is provided at each level to prohibit the counting of small strain variations around a given preset level.

Application of Digital Image Analysis to Determine Pancreatic Islet Mass and Purity in Clinical Islet Isolation and Transplantation

PubMed Central

Wang, Ling-jia; Kissler, Hermann J; Wang, Xiaojun; Cochet, Olivia; Krzystyniak, Adam; Misawa, Ryosuke; Golab, Karolina; Tibudan, Martin; Grzanka, Jakub; Savari, Omid; Grose, Randall; Kaufman, Dixon B; Millis, Michael; Witkowski, Piotr

2015-01-01

Pancreatic islet mass, represented by islet equivalent (IEQ), is the most important parameter in decision making for clinical islet transplantation. To obtain IEQ, the sample of islets is routinely counted manually under a microscope and discarded thereafter. Islet purity, another parameter in islet processing, is routinely acquired by estimation only. In this study, we validated our digital image analysis (DIA) system developed using the software of Image Pro Plus for islet mass and purity assessment. Application of the DIA allows to better comply with current good manufacturing practice (cGMP) standards. Human islet samples were captured as calibrated digital images for the permanent record. Five trained technicians participated in determination of IEQ and purity by manual counting method and DIA. IEQ count showed statistically significant correlations between the manual method and DIA in all sample comparisons (r >0.819 and p < 0.0001). Statistically significant difference in IEQ between both methods was found only in High purity 100μL sample group (p = 0.029). As far as purity determination, statistically significant differences between manual assessment and DIA measurement was found in High and Low purity 100μL samples (p<0.005), In addition, islet particle number (IPN) and the IEQ/IPN ratio did not differ statistically between manual counting method and DIA. In conclusion, the DIA used in this study is a reliable technique in determination of IEQ and purity. Islet sample preserved as a digital image and results produced by DIA can be permanently stored for verification, technical training and islet information exchange between different islet centers. Therefore, DIA complies better with cGMP requirements than the manual counting method. We propose DIA as a quality control tool to supplement the established standard manual method for islets counting and purity estimation. PMID:24806436

Sampling characteristics and calibration of snorkel counts to estimate stream fish populations

USGS Publications Warehouse

Weaver, D.; Kwak, Thomas J.; Pollock, Kenneth

2014-01-01

Snorkeling is a versatile technique for estimating lotic fish population characteristics; however, few investigators have evaluated its accuracy at population or assemblage levels. We evaluated the accuracy of snorkeling using prepositioned areal electrofishing (PAE) for estimating fish populations in a medium-sized Appalachian Mountain river during fall 2008 and summer 2009. Strip-transect snorkel counts were calibrated with PAE counts in identical locations among macrohabitats, fish species or taxa, and seasons. Mean snorkeling efficiency (i.e., the proportion of individuals counted from the true population) among all taxa and seasons was 14.7% (SE, 2.5%), and the highest efficiencies were for River Chub Nocomis micropogon at 21.1% (SE, 5.9%), Central Stoneroller Campostoma anomalum at 20.3% (SE, 9.6%), and darters (Percidae) at 17.1% (SE, 3.7%), whereas efficiencies were lower for shiners (Notropis spp., Cyprinella spp., Luxilus spp.) at 8.2% (SE, 2.2%) and suckers (Catostomidae) at 6.6% (SE, 3.2%). Macrohabitat type, fish taxon, or sampling season did not significantly explain variance in snorkeling efficiency. Mean snorkeling detection probability (i.e., probability of detecting at least one individual of a taxon) among fish taxa and seasons was 58.4% (SE, 6.1%). We applied the efficiencies from our calibration study to adjust snorkel counts from an intensive snorkeling survey conducted in a nearby reach. Total fish density estimates from strip-transect counts adjusted for snorkeling efficiency were 7,288 fish/ha (SE, 1,564) during summer and 15,805 fish/ha (SE, 4,947) during fall. Precision of fish density estimates is influenced by variation in snorkeling efficiency and sample size and may be increased with additional sampling effort. These results demonstrate the sampling properties and utility of snorkeling to characterize lotic fish assemblages with acceptable efficiency and detection probability, less effort, and no mortality, compared with traditional sampling methods.

Effects of lint cleaning on lint trash particle size distribution

USDA-ARS?s Scientific Manuscript database

Cotton quality trash measurements used today typically yield a single value for trash parameters for a lint sample (i.e. High Volume Instrument – percent area; Advanced Fiber Information System – total count, trash size, dust count, trash count, and visible foreign matter). A Cotton Trash Identifica...

A simple device to convert a small-animal PET scanner into a multi-sample tissue and injection syringe counter.

PubMed

Green, Michael V; Seidel, Jurgen; Choyke, Peter L; Jagoda, Elaine M

2017-10-01

We describe a simple fixture that can be added to the imaging bed of a small-animal PET scanner that allows for automated counting of multiple organ or tissue samples from mouse-sized animals and counting of injection syringes prior to administration of the radiotracer. The combination of imaging and counting capabilities in the same machine offers advantages in certain experimental settings. A polyethylene block of plastic, sculpted to mate with the animal imaging bed of a small-animal PET scanner, is machined to receive twelve 5-ml containers, each capable of holding an entire organ from a mouse-sized animal. In addition, a triangular cross-section slot is machined down the centerline of the block to secure injection syringes from 1-ml to 3-ml in size. The sample holder is scanned in PET whole-body mode to image all samples or in one bed position to image a filled injection syringe. Total radioactivity in each sample or syringe is determined from the reconstructed images of these objects using volume re-projection of the coronal images and a single region-of-interest for each. We tested the accuracy of this method by comparing PET estimates of sample and syringe activity with well counter and dose calibrator estimates of these same activities. PET and well counting of the same samples gave near identical results (in MBq, R 2 =0.99, slope=0.99, intercept=0.00-MBq). PET syringe and dose calibrator measurements of syringe activity in MBq were also similar (R 2 =0.99, slope=0.99, intercept=- 0.22-MBq). A small-animal PET scanner can be easily converted into a multi-sample and syringe counting device by the addition of a sample block constructed for that purpose. This capability, combined with live animal imaging, can improve efficiency and flexibility in certain experimental settings. Copyright © 2017 Elsevier Inc. All rights reserved.

Microbiological Quality and Incidence of Salmonella on Cherry Tomatoes at Retail in Querétaro, México.

PubMed

Leal-Cervantes, Marla G; Arvizu-Medrano, Sofía M; Martínez-Peniche, Ramón; Martínez-Gonzáles, Nanci E; Hernández-Iturriaga, Montserrat

2018-04-01

Multiple outbreaks related to Salmonella in tomatoes require an evaluation of the risk associated with cherry tomatoes due to the increase in its production, consumption, and marketing in Mexico's central region. The purpose of this study was to determine the microbial quality of cherry tomatoes obtained from two retail sale points (supermarkets and local markets). Cherry tomato samples (333) were collected from four supermarkets and from four local markets, and the contents of aerobic plate count, molds and yeasts, total coliforms, and Escherichia coli were quantified; the presence of Salmonella was simultaneously determined. The median values of the microbial populations were obtained, and the data were analyzed per the sampling site by using the Wilcoxon and Kruskal-Wallis tests. The median of aerobic plate count content in tomatoes obtained from supermarkets ranged between 2.2 and 4.4 log CFU/g, and in markets from 2.9 to 4.8 log CFU/g. For molds and yeasts, the tomatoes from supermarkets (2.0 to 4.1 log CFU/g) and markets (1.5 to 4.5 log CFU/g) showed similar contents. Regardless of the sampling site, the values of total coliforms were very low, ranging from 1.0 to 1.8 log CFU/g. E. coli was detected in 5.4 and 20.1% of samples from supermarkets and markets, respectively; in both sites, the content was low (0.3 to 5.8 most probable number per g). The incidence of Salmonella was 14.1% in supermarkets and 7.8% in local markets. The results obtained from this investigation highlight the elevated risk for consumer health associated with the ingestion of cherry tomatoes.

Pumpless Microflow Cytometry Enabled by Viscosity Modulation and Immunobead Labeling.

PubMed

Kim, Byeongyeon; Oh, Sein; Shin, Suyeon; Yim, Sang-Gu; Yang, Seung Yun; Hahn, Young Ki; Choi, Sungyoung

2018-06-19

Major challenges of miniaturizing flow cytometry include obviating the need for bulky, expensive, and complex pump-based fluidic and laser-based optical systems while retaining the ability to detect target cells based on their unique surface receptors. We addressed these critical challenges by (i) using a viscous liquid additive to control flow rate passively, without external pumping equipment, and (ii) adopting an immunobead assay that can be quantified with a portable fluorescence cell counter based on a blue light-emitting diode. Such novel features enable pumpless microflow cytometry (pFC) analysis by simply dropping a sample solution onto the inlet reservoir of a disposable cell-counting chamber. With our pFC platform, we achieved reliable cell counting over a dynamic range of 9-298 cells/μL. We demonstrated the practical utility of the platform by identifying a type of cancer cell based on CD326, the epithelial cell adhesion molecule. This portable microflow cytometry platform can be applied generally to a range of cell types using immunobeads labeled with specific antibodies, thus making it valuable for cell-based and point-of-care diagnostics.

Winter habitat occurrence patterns of temperate migrant birds in Belize

USGS Publications Warehouse

Dawson, D.K.; Robbins, C.S.; Sauer, J.R.

1992-01-01

We used mist nets and point counts to sample bird populations in 61 sites in Belize during January-March of 1987-1991. Sites were classified as forest, second growth, woody agricultural crops (citrus, mango, cacao, and cashew), or non-woody agricultural crops (rice and sugar cane). We evaluated patterns of occurence of wintering temperate migrant bird species in these habitats. Mist net captures of 22 of 31 migrant species differed significantly among habitats. Of these, 13 species were captured more frequently in the agricultural habitats. American Redstart (Setophaga ruticilla), Black-and-white Warbler (Mniotilta varia), and Magnolia Warbler (Dendroica magnolia) were among the species captured most frequently in woody agricultural habitats; captures of Common Yellowthroat (Geothlypis trichas), Indigo Bunting (Passerina cyanea), and Northern (lcterus galbula) and Orchard orioles (I. spur/anus) were highest in the non-woody agricultural sites. We relate these occurrence patterns to trends in breeding populations in North America. While count data provide a wide picture of winter habitat distribution of migrants, more intensive work is necessary to assess temporal and geographic variation of migrant bird use of agricultural habitats.

Study of the counting efficiency of a WBC setup by using a computational 3D human body library in sitting position based on polygonal mesh surfaces.

PubMed

Fonseca, T C Ferreira; Bogaerts, R; Lebacq, A L; Mihailescu, C L; Vanhavere, F

2014-04-01

A realistic computational 3D human body library, called MaMP and FeMP (Male and Female Mesh Phantoms), based on polygonal mesh surface geometry, has been created to be used for numerical calibration of the whole body counter (WBC) system of the nuclear power plant (NPP) in Doel, Belgium. The main objective was to create flexible computational models varying in gender, body height, and mass for studying the morphology-induced variation of the detector counting efficiency (CE) and reducing the measurement uncertainties. First, the counting room and an HPGe detector were modeled using MCNPX (Monte Carlo radiation transport code). The validation of the model was carried out for different sample-detector geometries with point sources and a physical phantom. Second, CE values were calculated for a total of 36 different mesh phantoms in a seated position using the validated Monte Carlo model. This paper reports on the validation process of the in vivo whole body system and the CE calculated for different body heights and weights. The results reveal that the CE is strongly dependent on the individual body shape, size, and gender and may vary by a factor of 1.5 to 3 depending on the morphology aspects of the individual to be measured.

Sensing and enumerating rare circulating cells with diffuse light

NASA Astrophysics Data System (ADS)

Zettergren, Eric; Vickers, Dwayne; Niedre, Mark

2011-02-01

Detection and quantification of circulating cells in live animals is a challenging and important problem in many areas of biomedical research. Current methods involve extraction of blood samples and counting of cells ex-vivo. Since only small blood volumes are analyzed at specific time points, monitoring of changes in cell populations over time is difficult and rare cells often escape detection. The goal of this research is to develop a method for enumerating very rare circulating cells in the bloodstream non-invasively. This would have many applications in biomedical research, including monitoring of cancer metastasis and tracking of hematopoietic stem cells. In this work we describe the optical configuration of our instrument which allows fluorescence detection of single cells in diffusive media at the mesoscopic scale. Our instrument design consists of two continuous wave laser diode sources and an 8-channel fiber coupled multi-anode photon counting PMT. Fluorescence detector fibers were arranged circularly around the target in a miniaturized ring configuration. Cell-simulating fluorescent microspheres and fluorescently-labeled cells were passed through a limb mimicking phantom with similar optical properties and background fluorescence as a limb of a mouse. Our data shows that we are able to successfully detect and count these with high quantitative accuracy. Future work includes characterization of our instrument using fluorescently labeled cells in-vivo. If successful, this technique would allow several orders of magnitude in vivo detection sensitivity improvement versus current approaches.

In-line assay monitor for uranium hexafluoride

DOEpatents

Wallace, Steven A.

1981-01-01

An in-line assay monitor for determining the content of uranium-235 in a uranium hexafluoride gas isotopic separation system is provided which removes the necessity of complete access to the operating parameters of the system for determining the uranium-235 content. The monitor is intended for uses such as safeguard applications to assure that weapons grade uranium is not being produced in an enrichment cascade. The method and monitor for carrying out the method involve cooling of a radiation pervious chamber connected in fluid communication with the selected point in the system to withdraw a specimen and solidify the specimen in the chamber. The specimen is irradiated by means of an ionizing radiation source of energy different from that of the 185 keV gamma emissions from the uranium-235 present in the specimen. Simultaneously, the gamma emissions from the uranium-235 of the specimen and the source emissions transmitted through the sample are counted and stored in a multiple channel analyzer. The uranium-235 content of the specimen is determined from the comparison of the accumulated 185 keV energy counts and the reference energy counts. The latter is used to measure the total uranium isotopic content of the specimen. The process eliminates the necessity of knowing the system operating conditions and yet obtains the necessary data without need for large scintillation crystals and sophisticated mechanical designs.

The MUSE-Wide survey: detection of a clustering signal from Lyman α emitters in the range 3 < z < 6

NASA Astrophysics Data System (ADS)

Diener, C.; Wisotzki, L.; Schmidt, K. B.; Herenz, E. C.; Urrutia, T.; Garel, T.; Kerutt, J.; Saust, R. L.; Bacon, R.; Cantalupo, S.; Contini, T.; Guiderdoni, B.; Marino, R. A.; Richard, J.; Schaye, J.; Soucail, G.; Weilbacher, P. M.

2017-11-01

We present a clustering analysis of a sample of 238 Ly α emitters at redshift 3 ≲ z ≲ 6 from the MUSE-Wide survey. This survey mosaics extragalactic legacy fields with 1h MUSE pointings to detect statistically relevant samples of emission line galaxies. We analysed the first year observations from MUSE-Wide making use of the clustering signal in the line-of-sight direction. This method relies on comparing pair-counts at close redshifts for a fixed transverse distance and thus exploits the full potential of the redshift range covered by our sample. A clear clustering signal with a correlation length of r0=2.9^{+1.0}_{-1.1} Mpc (comoving) is detected. Whilst this result is based on only about a quarter of the full survey size, it already shows the immense potential of MUSE for efficiently observing and studying the clustering of Ly α emitters.

The 124Sb activity standardization by gamma spectrometry for medical applications

NASA Astrophysics Data System (ADS)

de Almeida, M. C. M.; Iwahara, A.; Delgado, J. U.; Poledna, R.; da Silva, R. L.

2010-07-01

This work describes a metrological activity determination of 124Sb, which can be used as radiotracer, applying gamma spectrometry methods with hyper pure germanium detector and efficiency curves. This isotope with good activity and high radionuclidic purity is employed in the form of meglumine antimoniate (Glucantime) or sodium stibogluconate (Pentostam) to treat leishmaniasis. 124Sb is also applied in animal organ distribution studies to solve some questions in pharmacology. 124Sb decays by β-emission and it produces several photons (X and gamma rays) with energy varying from 27 to 2700 keV. Efficiency curves to measure point 124Sb solid sources were obtained from a 166mHo standard that is a multi-gamma reference source. These curves depend on radiation energy, sample geometry, photon attenuation, dead time and sample-detector position. Results for activity determination of 124Sb samples using efficiency curves and a high purity coaxial germanium detector were consistent in different counting geometries. Also uncertainties of about 2% ( k=2) were obtained.

The distribution of galaxies within the 'Great Wall'

NASA Technical Reports Server (NTRS)

Ramella, Massimo; Geller, Margaret J.; Huchra, John P.

1992-01-01

The galaxy distribution within the 'Great Wall', the most striking feature in the first three 'slices' of the CfA redshift survey extension is examined. The Great Wall is extracted from the sample and is analyzed by counting galaxies in cells. The 'local' two-point correlation function within the Great Wall is computed and the local correlation length, is estimated 15/h Mpc, about 3 times larger than the correlation length for the entire sample. The redshift distribution of galaxies in the pencil-beam survey by Broadhurst et al. (1990) shows peaks separated about by large 'voids', at least to a redshift of about 0.3. The peaks might represent the intersections of their about 5/h Mpc pencil beams with structures similar to the Great Wall. Under this hypothesis, sampling of the Great Walls shows that l approximately 12/h Mpc is the minimum projected beam size required to detect all the 'walls' at redshifts between the peak of the selection function and the effective depth of the survey.

Method and apparatus for detecting dilute concentrations of radioactive xenon in samples of xenon extracted from the atmosphere

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

Warburton, William K.; Hennig, Wolfgang G.

A method and apparatus for measuring the concentrations of radioxenon isotopes in a gaseous sample wherein the sample cell is surrounded by N sub-detectors that are sensitive to both electrons and to photons from radioxenon decays. Signal processing electronics are provided that can detect events within the sub-detectors, measure their energies, determine whether they arise from electrons or photons, and detect coincidences between events within the same or different sub-detectors. The energies of detected two or three event coincidences are recorded as points in associated two or three-dimensional histograms. Counts within regions of interest in the histograms are then usedmore » to compute estimates of the radioxenon isotope concentrations. The method achieves lower backgrounds and lower minimum detectable concentrations by using smaller detector crystals, eliminating interference between double and triple coincidence decay branches, and segregating double coincidences within the same sub-detector from those occurring between different sub-detectors.« less

Effects of Sachet Water Consumption on Exposure to Microbe-Contaminated Drinking Water: Household Survey Evidence from Ghana

PubMed Central

Wright, Jim; Dzodzomenyo, Mawuli; Wardrop, Nicola A.; Johnston, Richard; Hill, Allan; Aryeetey, Genevieve; Adanu, Richard

2016-01-01

There remain few nationally representative studies of drinking water quality at the point of consumption in developing countries. This study aimed to examine factors associated with E. coli contamination in Ghana. It drew on a nationally representative household survey, the 2012−2013 Living Standards Survey 6, which incorporated a novel water quality module. E. coli contamination in 3096 point-of-consumption samples was examined using multinomial regression. Surface water use was the strongest risk factor for high E. coli contamination (relative risk ratio (RRR) = 32.3, p < 0.001), whilst packaged (sachet or bottled) water use had the greatest protective effect (RRR = 0.06, p < 0.001), compared to water piped to premises. E. coli contamination followed plausible patterns with digit preference (tendency to report values ending in zero) in bacteria counts. The analysis suggests packaged drinking water use provides some protection against point-of-consumption E. coli contamination and may therefore benefit public health. It also suggests viable water quality data can be collected alongside household surveys, but field protocols require further revision. PMID:27005650

Effects of Sachet Water Consumption on Exposure to Microbe-Contaminated Drinking Water: Household Survey Evidence from Ghana.

PubMed

Wright, Jim; Dzodzomenyo, Mawuli; Wardrop, Nicola A; Johnston, Richard; Hill, Allan; Aryeetey, Genevieve; Adanu, Richard

2016-03-09

There remain few nationally representative studies of drinking water quality at the point of consumption in developing countries. This study aimed to examine factors associated with E. coli contamination in Ghana. It drew on a nationally representative household survey, the 2012-2013 Living Standards Survey 6, which incorporated a novel water quality module. E. coli contamination in 3096 point-of-consumption samples was examined using multinomial regression. Surface water use was the strongest risk factor for high E. coli contamination (relative risk ratio (RRR) = 32.3, p < 0.001), whilst packaged (sachet or bottled) water use had the greatest protective effect (RRR = 0.06, p < 0.001), compared to water piped to premises. E. coli contamination followed plausible patterns with digit preference (tendency to report values ending in zero) in bacteria counts. The analysis suggests packaged drinking water use provides some protection against point-of-consumption E. coli contamination and may therefore benefit public health. It also suggests viable water quality data can be collected alongside household surveys, but field protocols require further revision.

Tutorial on X-ray photon counting detector characterization.

PubMed

Ren, Liqiang; Zheng, Bin; Liu, Hong

2018-01-01

Recent advances in photon counting detection technology have led to significant research interest in X-ray imaging. As a tutorial level review, this paper covers a wide range of aspects related to X-ray photon counting detector characterization. The tutorial begins with a detailed description of the working principle and operating modes of a pixelated X-ray photon counting detector with basic architecture and detection mechanism. Currently available methods and techniques for charactering major aspects including energy response, noise floor, energy resolution, count rate performance (detector efficiency), and charge sharing effect of photon counting detectors are comprehensively reviewed. Other characterization aspects such as point spread function (PSF), line spread function (LSF), contrast transfer function (CTF), modulation transfer function (MTF), noise power spectrum (NPS), detective quantum efficiency (DQE), bias voltage, radiation damage, and polarization effect are also remarked. A cadmium telluride (CdTe) pixelated photon counting detector is employed for part of the characterization demonstration and the results are presented. This review can serve as a tutorial for X-ray imaging researchers and investigators to understand, operate, characterize, and optimize photon counting detectors for a variety of applications.

Soudan Low Background Counting Facility (SOLO)

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

Attisha, Michael; Viveiros, Luiz de; Gaitksell, Richard

2005-09-08

The Soudan Low Background Counting Facility (SOLO) has been in operation at the Soudan Mine, MN since March 2003. In the past two years, we have gamma-screened samples for the Majorana, CDMS and XENON experiments. With individual sample exposure times of up to two weeks we have measured sample contamination down to the 0.1 ppb level for 238U / 232Th, and down to the 0.25 ppm level for 40K.

IRF4 Variants Have Age-Specific Effects on Nevus Count and Predispose to Melanoma

PubMed Central

Duffy, David L.; Iles, Mark M.; Glass, Dan; Zhu, Gu; Barrett, Jennifer H.; Höiom, Veronica; Zhao, Zhen Z.; Sturm, Richard A.; Soranzo, Nicole; Hammond, Chris; Kvaskoff, Marina; Whiteman, David C.; Mangino, Massimo; Hansson, Johan; Newton-Bishop, Julia A.; Bataille, Veronique; Hayward, Nicholas K.; Martin, Nicholas G.; Bishop, D. Timothy; Spector, Timothy D.; Montgomery, Grant W.

2010-01-01

High melanocytic nevus count is a strong predictor of melanoma risk. A GWAS of nevus count in Australian adolescent twins identified an association of nevus count with the interferon regulatory factor 4 gene (IRF4 [p = 6 × 10−9]). There was a strong genotype-by-age interaction, which was replicated in independent UK samples of adolescents and adults. The rs12203592∗T allele was associated with high nevus counts and high freckling scores in adolescents, but with low nevus counts and high freckling scores in adults. The rs12203592∗T increased counts of flat (compound and junctional) nevi in Australian adolescent twins, but decreased counts of raised (intradermal) nevi. In combined analysis of melanoma case-control data from Australia, the UK, and Sweden, the rs12203592∗C allele was associated with melanoma (odds ratio [OR] 1.15, p = 4 × 10−3), most significantly on the trunk (OR = 1.33, p = 2.5 × 10−5). The melanoma association was corroborated in a GWAS performed by the GenoMEL consortium for an adjacent SNP, rs872071 (rs872071∗T: OR 1.14, p = 0.0035; excluding Australian, the UK, and Swedish samples typed at rs12203592: OR 1.08, p = 0.08). PMID:20602913

Comparison of point-of-care methods for preparation of platelet concentrate (platelet-rich plasma).

PubMed

Weibrich, Gernot; Kleis, Wilfried K G; Streckbein, Philipp; Moergel, Maximilian; Hitzler, Walter E; Hafner, Gerd

2012-01-01

This study analyzed the concentrations of platelets and growth factors in platelet-rich plasma (PRP), which are likely to depend on the method used for its production. The cellular composition and growth factor content of platelet concentrates (platelet-rich plasma) produced by six different procedures were quantitatively analyzed and compared. Platelet and leukocyte counts were determined on an automatic cell counter, and analysis of growth factors was performed using enzyme-linked immunosorbent assay. The principal differences between the analyzed PRP production methods (blood bank method of intermittent flow centrifuge system/platelet apheresis and by the five point-of-care methods) and the resulting platelet concentrates were evaluated with regard to resulting platelet, leukocyte, and growth factor levels. The platelet counts in both whole blood and PRP were generally higher in women than in men; no differences were observed with regard to age. Statistical analysis of platelet-derived growth factor AB (PDGF-AB) and transforming growth factor β1 (TGF-β1) showed no differences with regard to age or gender. Platelet counts and TGF-β1 concentration correlated closely, as did platelet counts and PDGF-AB levels. There were only rare correlations between leukocyte counts and PDGF-AB levels, but comparison of leukocyte counts and PDGF-AB levels demonstrated certain parallel tendencies. TGF-β1 levels derive in substantial part from platelets and emphasize the role of leukocytes, in addition to that of platelets, as a source of growth factors in PRP. All methods of producing PRP showed high variability in platelet counts and growth factor levels. The highest growth factor levels were found in the PRP prepared using the Platelet Concentrate Collection System manufactured by Biomet 3i.

Mealtime Insulin Dosing by Carbohydrate Counting in Hospitalized Cardiology Patients: A Retrospective Cohort Study.

PubMed

Thurber, Kristina M; Dierkhising, Ross A; Reiland, Sarah A; Pearson, Kristina K; Smith, Steven A; O'Meara, John G

2016-01-01

Carbohydrate counting may improve glycemic control in hospitalized cardiology patients by providing individualized insulin doses tailored to meal consumption. The purpose of this study was to compare glycemic outcomes with mealtime insulin dosed by carbohydrate counting versus fixed dosing in the inpatient setting. This single-center retrospective cohort study included 225 adult medical cardiology patients who received mealtime, basal, and correction-scale insulin concurrently for at least 72 h and up to 7 days in the interval March 1, 2010-November 7, 2013. Mealtime insulin was dosed by carbohydrate counting or with fixed doses determined prior to meal intake. An inpatient diabetes consult service was responsible for insulin management. Exclusion criteria included receipt of an insulin infusion. The primary end point compared mean daily postprandial glucose values, whereas secondary end points included comparison of preprandial glucose values and mean daily rates of hypoglycemia. Mean postprandial glucose level on Day 7 was 204 and 183 mg/dL in the carbohydrate counting and fixed mealtime dose groups, respectively (unadjusted P=0.04, adjusted P=0.12). There were no statistical differences between groups on Days 2-6. Greater rates of preprandial hypoglycemia were observed in the carbohydrate counting cohort on Day 5 (8.6% vs. 1.5%, P=0.02), Day 6 (1.7% vs. 0%, P=0.01), and Day 7 (7.1% vs. 0%, P=0.008). No differences in postprandial hypoglycemia were seen. Mealtime insulin dosing by carbohydrate counting was associated with similar glycemic outcomes as fixed mealtime insulin dosing, except for a greater incidence of preprandial hypoglycemia. Additional comparative studies that include hospital outcomes are needed.

Basic characteristics of plasma rich in growth factors (PRGF): blood cell components and biological effects.

PubMed

Nishiyama, Kazuhiko; Okudera, Toshimitsu; Watanabe, Taisuke; Isobe, Kazushige; Suzuki, Masashi; Masuki, Hideo; Okudera, Hajime; Uematsu, Kohya; Nakata, Koh; Kawase, Tomoyuki

2016-11-01

Platelet-rich plasma (PRP) is widely used in regenerative medicine because of its high concentrations of various growth factors and platelets. However, the distribution of blood cell components has not been investigated in either PRP or other PRP derivatives. In this study, we focused on plasma rich in growth factors (PRGF), a PRP derivative, and analyzed the distributions of platelets and white blood cells (WBCs). Peripheral blood samples were collected from healthy volunteers ( N  = 14) and centrifuged to prepare PRGF and PRP. Blood cells were counted using an automated hematology analyzer. The effects of PRP and PRGF preparations on cell proliferation were determined using human periosteal cells. In the PRGF preparations, both red blood cells and WBCs were almost completely eliminated, and platelets were concentrated by 2.84-fold, whereas in the PRP preparations, both platelets and WBCs were similarly concentrated by 8.79- and 5.51-fold, respectively. Platelet counts in the PRGF preparations were positively correlated with platelet counts in the whole blood samples, while the platelet concentration rate was negatively correlated with red blood cell counts in the whole blood samples. In contrast, platelet counts and concentration rates in the PRP preparations were significantly influenced by WBC counts in whole blood samples. The PRP preparations, but not the PRGF preparations, significantly suppressed cell growth at higher doses in vitro. Therefore, these results suggest that PRGF preparations can clearly be distinguished from PRP preparations by both inclusion of WBCs and dose-dependent stimulation of periosteal cell proliferation in vitro.

Basic characteristics of plasma rich in growth factors (PRGF): blood cell components and biological effects

PubMed Central

Nishiyama, Kazuhiko; Okudera, Toshimitsu; Watanabe, Taisuke; Isobe, Kazushige; Suzuki, Masashi; Masuki, Hideo; Okudera, Hajime; Uematsu, Kohya; Nakata, Koh

2016-01-01

Abstract Platelet‐rich plasma (PRP) is widely used in regenerative medicine because of its high concentrations of various growth factors and platelets. However, the distribution of blood cell components has not been investigated in either PRP or other PRP derivatives. In this study, we focused on plasma rich in growth factors (PRGF), a PRP derivative, and analyzed the distributions of platelets and white blood cells (WBCs). Peripheral blood samples were collected from healthy volunteers (N = 14) and centrifuged to prepare PRGF and PRP. Blood cells were counted using an automated hematology analyzer. The effects of PRP and PRGF preparations on cell proliferation were determined using human periosteal cells. In the PRGF preparations, both red blood cells and WBCs were almost completely eliminated, and platelets were concentrated by 2.84‐fold, whereas in the PRP preparations, both platelets and WBCs were similarly concentrated by 8.79‐ and 5.51‐fold, respectively. Platelet counts in the PRGF preparations were positively correlated with platelet counts in the whole blood samples, while the platelet concentration rate was negatively correlated with red blood cell counts in the whole blood samples. In contrast, platelet counts and concentration rates in the PRP preparations were significantly influenced by WBC counts in whole blood samples. The PRP preparations, but not the PRGF preparations, significantly suppressed cell growth at higher doses in vitro. Therefore, these results suggest that PRGF preparations can clearly be distinguished from PRP preparations by both inclusion of WBCs and dose‐dependent stimulation of periosteal cell proliferation in vitro. PMID:29744155