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1.
The objective of this study was to evaluate the ability of near-infrared reflectance spectroscopy (NIRS) to discriminate between pregnant and nonpregnant ewes in early stages of pregnancy after artificial insemination (AI) from blood plasma. Samples were collected using jugular puncture at 18 and 25 days after AI from 188 Rasa Aragonesa and Ansotana ewes. Plasma samples were analyzed for pregnancy-associated glycoprotein (PAG) and progesterone (P4) using ELISA commercial kits. The spectra of plasma samples were recorded in the visible and near-infrared ranges. The performance of these tests were compared, using as criterion standard the pregnancy status determined using transabdominal ultrasonography at 45 days after AI. Pregnancy rate was 47.9% (90/188). At Day 18, sensitivity was similar in NIRS and P4 tests (98.9% vs. 100%; not significant) and greater than PAG (32.2%; both P < 0.001). Specificity was similar in NIRS and PAG tests (both 100%) and greater than that of P4 (84.7%; P < 0.001). At Day 25, sensitivity and specificity of NIRS and PAG were both 100%. It can be concluded that NIRS was an accurate method of diagnosis of pregnancy at Days 18 and 25 after AI in ewes.  相似文献   

2.
Aim Migration has been suggested to promote large breeding ranges among birds because of the greater mobility of migratory compared with non‐migratory species, but migration has also been suggested to restrict breeding ranges because of evolutionary constraints imposed by the genetically based migration control programme. We aim to investigate the association between migration and the breeding ranges of both land birds and pelagic birds breeding in the Arctic region. Location The Arctic region. Methods Information on breeding and wintering ranges and migratory status of bird species breeding in the arctic tundra biome was compiled from the literature. The association between breeding range, migration distance and primary winter habitat was tested using multivariate generalized linear models and pair‐wise Mann–Whitney U‐tests. Phylogenetic effects were tested for using Mantel’s permutation tests. Results We found different relationships depending on the species’ major winter habitat. Among birds that are pelagic during winter, long‐distance migrants have the largest breeding ranges, while among terrestrial birds, residents and short‐distance migrants have the largest breeding ranges. Breeding ranges of coastal birds of all migratory distance classes are comparatively restricted. Main conclusions As a new explanation for this pattern we suggest that the possibility of colonizing large winter ranges is a key factor for the subsequent expansion of breeding ranges in arctic bird communities and possibly also in bird communities of other regions of the world. Because of the reversal in the relative extent of continents and oceans between the hemispheres, longitudinally wide winter ranges are more likely for long‐distance than short‐distance migrants among pelagic birds, while the reverse holds true for birds that use terrestrial winter habitats. For coastal birds both continents and oceans form barriers restricting colonization of extensive winter quarters and consequently also of extensive breeding ranges, regardless of the distance to the winter quarters.  相似文献   

3.
The feasibility of using Portland cement and organobentonite to stabilize and solidify Polycyclic Aromatic Hydrocarbons (PAH) contaminated soil was examined. Naphthalene and phenanthrene in solid and dissolved phases were selected as PAHs compounds to represent organic contaminants in the soil. Different tests including Toxicity Characteristics Leaching Procedure (TCLP), Unconfined Compressive Strength (UCS), and permeability tests were conducted on the stabilization/solidification (S/S) contaminated soils. The leaching test results confirmed a significant reduction in the leaching of naphthalene and phenanthrene from the stabilized soil specimen by adding 2%, 5%, and 10% of organoclay during solidification/stabilization. Based on the results for the tested ranges of cement and organoclay for S/S contaminated soil, the optimum mix design includes 5% of cement and 2% of organoclay. The observation in this study confirmed that organoclay particles sorbed the organic contaminates and therefore naphthalene and phenanthrene leachate concentration will be reduced. Moreover, results show that increasing the curing time of S/S products reduces the naphthalene and phenanthrene leachate concentration.  相似文献   

4.
Four North American trees are becoming invasive species in Western Europe: Acer negundo, Prunus serotina, Quercus rubra, and Robinia pseudoacacia. However, their present and future potential risks of invasion have not been yet evaluated. Here, we assess niche shifts between the native and invasive ranges and the potential invasion risk of these four trees in Western Europe. We estimated niche conservatism in a multidimensional climate space using niche overlap Schoener's D, niche equivalence, and niche similarity tests. Niche unfilling and expansion were also estimated in analogous and nonanalogous climates. The capacity for predicting the opposite range between the native and invasive areas (transferability) was estimated by calibrating species distribution models (SDMs) on each range separately. Invasion risk was estimated using SDMs calibrated on both ranges and projected for 2050 climatic conditions. Our results showed that native and invasive niches were not equivalent with low niche overlap for all species. However, significant similarity was found between the invasive and native ranges of Q. rubra and R. pseudoacacia. Niche expansion was lower than 15% for all species, whereas unfilling ranged from 7 to 56% when it was measured using the entire climatic space and between 5 and 38% when it was measured using analogous climate only. Transferability was low for all species. SDMs calibrated over both ranges projected high habitat suitability in Western Europe under current and future climates. Thus, the North American and Western European ranges are not interchangeable irrespective of the studied species, suggesting that other environmental and/or biological characteristics are shaping their invasive niches. The current climatic risk of invasion is especially high for R. pseudoacacia and A. negundo. In the future, the highest risks of invasion for all species are located in Central and Northern Europe, whereas the risk is likely to decrease in the Mediterranean basin.  相似文献   

5.
Soluble microbial products (SMP) generated by activated sludge cultures receiving a mixed feed of phenol and glucose were characterized with respect to molecular weight (MW) distribution, octanol-water partition coefficient (K(ow)), and Microtox toxicity. Short-term batch reactor tests using 14C-labeled substrates were performed to collect SMP derived from each substrate, while long-term tests were performed with SMP accumulated over multiple feed cycles using fed-batch reactors receiving non-labeled substrates. Yield of SMP in the batch tests, 10%-20% for phenol and 2%-5% for glucose, differed for each substrate and was independent of initial concentration. The MW distribution (MWD) of SMP was independent of feed composition, and was bimodal in the < 1 kDa and 10-100 kDa MW ranges for phenol-derived SMP and predominantly < 1 kDa for glucose-derived SMP. In the non-labeled tests, the fraction of SMP of MW > 100 kDa increased with the proportion of glucose in the feed. The K(ow) of phenol-derived SMP was higher compared to glucose-derived SMP, indicating that the phenol-derived SMP were more hydrophobic. This was particularly true at an acidic pH, where the K(ow) was 4.2 +/- 1.0 for phenol-derived SMP versus 0.13 +/- 0.13 for glucose-derived SMP. Toxicity testing indicated that phenol-derived SMP, exerting a mean Microtox inhibition of 1%, were less toxic than phenol itself, and showed little correlation between toxicity and concentration. However, glucose-derived SMP were generally more toxic than glucose itself (a non-toxic substrate), and the toxicity increased linearly with the concentration of SMP.  相似文献   

6.
Aim Tests for faunal relaxation in reserves, particularly for mammals, have relied on comparisons of current species richness with estimates of species richness derived from historical range maps. However, any range map reflects the extent of occurrence of species and not necessarily the area of occupancy. Thus, estimates of historical species richness might be prone to error introduced by ‘false positives’, that is, a species might be considered to have been present in locations where it actually was not. The effect of such ‘false positives’ could bias statistical tests of faunal relaxation to type I error, and result in estimates of the extent of faunal relaxation in reserves greater than was actually the case. We evaluated the potential for errors in historical range maps to generate inflated estimates of historical species richness of mammals at sites that are reserves today. Location Canadian national parks in the Canadian portion of the Alleghenian‐‐Illinoian mammal province in south‐eastern Canada (the maritime region and parts of southern Québec, Ontario and Manitoba). Methods The effect of varying levels of error in range maps on estimates of historical species richness was tested using geographical information systems (GIS)‐based statistical sampling of simulated historical ranges. Species’ areas of occupancy were simulated to be only 25%, 75% and 95% of published historical species ranges. For each reserve, estimates of historical species richness from these simulated species ranges were then compared with similar, previously published estimates of richness based on published historical species ranges. Results Previous estimates of historical species richness for reserves were inversely and linearly related to the degree of inaccuracy of species ranges. If species ranges were, on average, 5% smaller than the accepted ranges, then estimates of historical species richness agreed with previous estimates in c. 90% of cases. However, if historical ranges were, on average, 25% smaller than those used in previous analyses, then previous historical estimates of species richness may be overestimates in c. 40% of cases. Main conclusions Estimates of the extent of faunal relaxation in reserves that use historical range maps to quantify past species richness appear to be sensitive to even small errors in the degree to which range maps may overestimate ‘area of occupancy’.  相似文献   

7.
Aim of the study was to determine practicality and to test accuracy of a new calibration technique firstly introduced in 1998 by Schmid and Bess for biomechanical human tests. This technique enables three-dimensional calibration of camera positions as well as the calculation of internal and external camera parameters. It can be performed unlike other three-dimensional calibration techniques as the first with a planar calibration grid and only one single video image (of each camera) to calculate all 3-D reconstruction parameters. The tests were performed using two albavision ACAM G-Cameras with a resolution of 480 (h) by 420 (v) pixels. The achievable accuracy of distance measurements in recent commercially available motion measurement systems usually ranges from about 0.09% to 1.77% and higher. Accuracy of 0.0373% was determined with the new calibration technique. The 95% confidence interval ranged at +/- 0.02322 mm, the RMS (root mean square) error at 0.18776 mm. Better accuracy, easier and faster calibration are features of this new calibration technique. Required time for complete calibration ranged below one minute. Anticipating this new method will have good practicality in gait analysis or in research and industry due to increased accuracy and ease of use.  相似文献   

8.
In comparing long‐bone cross‐sectional geometric properties between individuals, percentages of bone length are often used to identify equivalent locations along the diaphysis. In fragmentary specimens where bone lengths cannot be measured, however, these locations must be estimated more indirectly. In this study, we examine the effect of inaccurately located femoral and tibial midshafts on estimation of geometric properties. The error ranges were compared on 30 femora and tibiae from the Eneolithic and Bronze Age. Cross‐sections were obtained at each 1% interval from 60 to 40% of length using CT scans. Five percent of deviation from midshaft properties was used as the maximum acceptable error. Reliability was expressed by mean percentage differences, standard deviation of percentage differences, mean percentage absolute differences, limits of agreement, and mean accuracy range (MAR) (range within which mean deviation from true midshaft values was less than 5%). On average, tibial cortical area and femoral second moments of area are the least sensitive to positioning error, with mean accuracy ranges wide enough for practical application in fragmentary specimens (MAR = 40–130 mm). In contrast, tibial second moments of area are the most sensitive to error in midshaft location (MAR = 14–20 mm). Individuals present significant variation in morphology and thus in error ranges for different properties. For highly damaged fossil femora and tibiae we recommend carrying out additional tests to better establish specific errors associated with uncertain length estimates. Am J Phys Anthropol 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

9.
When animal home ranges overlap extensively in species lacking overt territorial behaviours, identifying exclusive core areas within individual ranges can be difficult. By analysing the size and overlap of successively smaller core areas among individual Eurasian red squirrels (Sciurus vulgaris), we determined exclusive areas within the home ranges of resident males and females. Possible effects of habitat composition and food supplies were explored by monitoring squirrels in different conifer forests and during years with low and high tree seed production. Using outlier-exclusive cores (OEC) revealed that the total ranges consisted of large sally zones (on average, 35% of the total minimum convex polygon [MCP] range) around home ranges with multi-nucleate cores. The mean OEC home range size did not differ between the sexes but was larger with poor food availability. Home ranges (99% incremental cluster polygons [ICP]) overlapped extensively between sexes (average overlap high food–low food: males by females 21–40%, females by males 43–45%) and among males (males by males 26–44%), while intrasexual overlap among females was low (9–10%). The overlap of inner cores among females rapidly approached zero, suggesting the intrasexual territoriality of 75% core areas. This was not the case among male squirrels, for which intrasexual overlap averaged only 4% at 50% but 18% at 75% core areas. Even the smallest inner cores had some degree of intersexual overlap, indicating that complete territoriality did not occur in this species. Female home ranges were more strongly affected by annual fluctuations in food supplies than male ranges. Females reduced the size of their food-based intrasexual territories when food availability increases. Males probably benefit from using larger home ranges and core areas, which overlap with the ranges of several females, by increasing their probability of successful mating.  相似文献   

10.
ObjectiveThe global epidemic of obesity and type 2 diabetes mellitus is the main driver of the growing global prevalence of nonalcoholic fatty liver disease (NAFLD). We aimed to review the current literature on NAFLD and nonalcoholic steatohepatitis (NASH) as it impacts children and adults.MethodsWe performed a literature search on fatty liver specifically NAFLD and NASH among children and adults.ResultsThe prevalence of NAFLD in children ranges from 8% to 12%, while the prevalence in adults ranges 25% to 48%. The prevalence of NASH among children with NAFLD is 23%, while it ranges from 13% to 65% in adults. There are similar risk factors for NAFLD among children and adults. However, in children, the diagnostic tests in the studies of NAFLD are limited to the elevation of the alanine aminotransferase level or a liver biopsy. In adults, additional diagnostic modalities, including noninvasive tests, have been used. From the spectrum of NAFLD, patients with NASH are predominantly at risk of progressive liver disease to cirrhosis and liver-related mortality. NAFLD is associated with impairment of health-related quality of life and substantial economic burden.ConclusionThe comprehensive burden (clinical, health-related quality of life, and economic) of NAFLD is high and increasing.  相似文献   

11.
This study explored efficient methods of harvesting the Tetraselmis sp. KCTC12236BP using flocculation and dissolved air flotation. Concentration ranges of flocculation agents were optimized using jar tests (batch flocculation experiments) using inorganic (aluminum sulfate, ferric sulfate) and organic (chitosan) flocculants in a pH range of 4 ~ 10. The optimal dosage and pH level were 1.2 g/L and pH 5 ~ 6 for aluminum sulfate, 0.7 g/L and pH 4 ~ 8 for ferric sulfate, and 5.0 mg/mL and pH 7 ~ 8 for chitosan. The highest harvesting efficiency achieved with each of the four compounds was 85.6, 92.6, 93, and 91.3%, respectively.  相似文献   

12.
Goldfish have a tetrachromatic color vision with a high discrimination ability for spectral colors as well as for object colors. We investigate the question whether goldfish organize the high number of discriminable colors in terms of color categories, i.e. in a few larger groups of colors independent of wavelength discrimination. Twenty-four goldfish were trained with food reward, each fish on one out of 13 wavelengths between 371 nm and 630 nm. In transfer tests two different wavelengths were presented, one shorter and one longer than the training wavelength, and the choice behavior was determined. Choice frequencies of ≥50% were assumed to indicate similarity to the training color. The wavelength ranges ≥50% were about 100 nm and twice as large as the just noticeable differences measured in wavelength discrimination tests (Fig. 7). The ranges were surprisingly about the same for all training wavelengths, provided the data were plotted on a wavelength scale weighted according to discrimination ability (Fig. 4). Thus, with the training method chosen goldfish showed a kind of categorization which, however, depends on training wavelength and discrimination ability. Generalization tests in which training wavelength and test wavelengths were shown separately for 2 min each gave the same results as wavelength discrimination tests (Figs. 5 and 6) and are, therefore, not indicative for color categories.  相似文献   

13.
A technique was developed for simultaneous detection of fenitrothion (FNT) and chlorpyrifos-methyl (CLT) using a photonic suspension array based on silica colloidal crystal beads (SCCBs). The SCCBs were encoded with the characteristic reflection peak originating from the stop-band of colloidal crystal. This approach avoids the bleaching, fading or potential interference seen when encoding by fluorescence. SCCBs with a nanopatterned surface had increased biomolecule binding capacity and improved stability. Under optimal conditions, the proposed suspension array allowed simultaneous detection of the selected pesticides in the ranges of 0.25 to 1024 ng/mL and 0.40 to 735.37 ng/mL, with the limits of detection (LODs) of 0.25 and 0.40 ng/mL, respectively. The suspension array was specific and had no significant cross-reactivity with other chemicals. The mean recoveries in tests in which samples were spiked with target standards were 82.35% to 109.90% with a standard deviation within 9.93% for CLT and 81.64% to 108.10% with a standard deviation within 8.82% for FNT. The proposed method shows a potentially powerful capability for fast quantitative analysis of pesticide residues.  相似文献   

14.
Neisseria meningitidis (Nm), Haemophilus influenzae (Hi), and Streptococcus pneumoniae (Sp) are the lead causes of bacterial meningitis. Detection of these pathogens from clinical specimens using traditional real-time PCR (rt-PCR) requires DNA extraction to remove the PCR inhibitors prior to testing, which is time consuming and labor intensive. In this study, five species-specific (Nm-sodC and -ctrA, Hi-hpd#1 and -hpd#3 and Sp-lytA) and six serogroup-specific rt-PCR tests (A, B, C, W, X, Y) targeting Nm capsular genes were evaluated in the two direct rt-PCR methods using PerfeCTa and 5x Omni that do not require DNA extraction. The sensitivity and specify of the two direct rt-PCR methods were compared to TaqMan traditional rt-PCR, the current standard rt-PCR method for the detection of meningitis pathogens. The LLD for all 11 rt-PCR tests ranged from 6,227 to 272,229 CFU/ml for TaqMan, 1,824–135,982 for 5x Omni, and 168–6,836 CFU/ml for PerfeCTa. The diagnostic sensitivity using TaqMan ranged from 89.2%-99.6%, except for NmB-csb, which was 69.7%. For 5x Omni, the sensitivity varied from 67.1% to 99.8%, with three tests below 90%. The sensitivity of these tests using PerfeCTa varied from 89.4% to 99.8%. The specificity ranges of the 11 tests were 98.0–99.9%, 97.5–99.9%, and 92.9–99.9% for TaqMan, 5x Omni, and PerfeCTa, respectively. PerfeCTa direct rt-PCR demonstrated similar or better sensitivity compared to 5x Omni direct rt-PCR or TaqMan traditional rt-PCR. Since the direct rt-PCR method does not require DNA extraction, it reduces the time and cost for processing CSF specimens, increases testing throughput, decreases the risk of cross-contamination, and conserves precious CSF. The direct rt-PCR method will be beneficial to laboratories with high testing volume.  相似文献   

15.
The possibility of controlling endospore formation by changing cultivation conditions was for the first time shown in acidophilic chemolithotrophic bacteria Sulfobacillus thermosulfidooxidans type strain 1269 and the thermotolerant strain K1 formerly described as "S. thermosulfidooxidans subsp. thermotolerans". Suppression of sporulation occurred when these strains were cultured in Manning's liquid medium with yeast extract. This medium was optimized by gradually reducing the concentrations of ferrous iron salts (the source of energy), phosphorous, nitrogen, and yeast extract and simultaneously increasing the concentrations of calcium, magnesium, and manganese (the elements important for sporogenesis) to attain higher yields of endospores by strains 1269 and K1. As a result, a new medium A was proposed, in which the life cycle of the strains studied culminated in sporulation at a level of 45 and 60%, respectively, of the total cell number. In a series of additional tests, the growth temperature and medium pH were adjusted to obtain the maximum yield of endospores. The optimal ranges found were 40-50 degrees C and pH 1.8-2.2 for strain 1269 and 35-40 degrees C and pH 2.5-2.7 for strain K1. An even higher yield of endospores, amounting to 55 and 75% for strains 1269 and K1, respectively, was obtained when the above growth conditions were combined (growth on medium A at optimal temperatures and pH). Our results suggest a new approach to optimizing sporulation by acidophilic chemolithotrophs, which consists in limiting the energy and nutrient sources and using temperature and pH values within the tolerance bounds of these cultures but outside their growth of optimum ranges.  相似文献   

16.
A multiple comparison procedure (MCP) is proposed for the comparison of all pairs of several independent samples. This MCP is essentially the closed procedure with union-intersection tests based on given single tests Qij for the minimal hypotheses Hij. In such cases where the α-levels of the nominal tests associated with the MCP can be exhausted, this MCP has a uniformly higher all pair power than any refined Bonferroni test using the same Qij. Two different general algorithms are described in section 3. A probability inequality for ranges of i.i.d. random variables which is useful for some algorithms is proved in section 4. Section 5 contains the application to independent normally distributed estimates and section 6 the comparisons of polynomial distributions by multivariate ranges. Further applications are possible. Tables of the 0.05-bounds for the tests of section 5 and 6 are enclosed.  相似文献   

17.
Ultrasensitive bioluminescence immunoassays for the determination of peptides and proteins (illustrated with human urinary kallikrein, bradykinin and the determination of human urinary kallikrein antibody titres) have been developed. The usable ranges of the standard curves are from 5 pg to 5000 pg per litre. The relative intra-assay coefficients of variation of the tests were between 2% and 6%, and the inter-assay coefficients of variation between 4% and 12%.  相似文献   

18.
The use of home ranges and microhabitats by female black-faced impalas Aepyceros melampus petersi was investigated using radio-telemetry over a 4-month period that coincided with parturition at Ongava Game Reserve, north-west Namibia. The aim of the study was to test how ranging patterns and microhabitat use were affected by the presence of young. The mean minimum convex polygon (MCP) home range of the 11 tracked female black-faced impalas exceeded the largest of home ranges of impalas elsewhere by at least six times, and females used significantly larger total ranges (MCPs) after birth, although (50% kernel) core areas did not change significantly. Females were more likely to be solitary or alone with a lamb in the first week of their lambs' lives than in the periods after or before that time, and they both shifted their home ranges and changed their microhabitat use after parturition. Decisions on microhabitat and space use by female black-faced impalas appeared to be affected by parturition.  相似文献   

19.
Glenn A. Marvin 《Oecologia》1998,114(1):133-144
To investigate the possible influence of variation in ecological and demographic factors on the spatial organization of the terrestrial plethodontid salamander Plethodon kentucki, I conducted a 3-year capture-recapture study and determined home-range characteristics and spatial relationships of individuals at two field sites that differed in predominant cover type and population density. Home ranges of adults were fixed and the home ranges of same-sex adult neighbors were mostly exclusive. The spatial arrangement of adult home ranges exhibited overall regularity or regularity within aggregations, whereas the distribution of juvenile home ranges was usually random. Analysis of nearest-neighbor sex indicated a positive intersexual association of adult home ranges. Removal studies provided evidence for defense of adult home ranges only at the high-density site. The distribution of home ranges was influenced by the presence of cover objects, but there was no significant relationship between adult body size and percent of home-range area with cover. Males overlapped the home ranges of gravid females significantly more often than those of non-gravid females, indicating that the distribution of gravid females had a strong influence on the distribution of male home ranges. In laboratory tests, increased male-male aggression during the breeding season suggests that males may compete for access to mates. At the high-density site, larger males may have benefited by having greater reproductive success than smaller males because they were more dominant and their home ranges overlapped a greater number of gravid-female home ranges. My results indicate that habitat structure and population density may influence the spatial organization and mating system of P. kentucki. Received: 26 May 1997 / Accepted: 9 October 1997  相似文献   

20.
The laboratory is dealing with reporting tests as information needed to make clinical decisions. The traditional statistical quality control measures which assigns reference ranges based on 95 percent confidence intervals is insufficient for diagnostic tests that assign risk. We construct a basis for risk assignment by a method that builds on the 2 x 2 contingency table used to calculate the C2 goodness-of-fit and Bayesian estimates. The widely used logistic regression is a subset of the regression method, as it only considers dichotomous outcome choices. We use examples of multivalued predictor(s) and a multivalued as well as dichotomous outcome. Outcomes analyses are quite easy using the ordinal logit regression model.  相似文献   

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