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1.
Since the mid-twentieth century, fisher populations (Pekania pennanti) increased in several eastern jurisdictions of North America, particularly in the northern part of the species’ range. Changes in fisher distribution have led to increased overlap with the southern portion of the range of American marten (Martes americana), whose populations may be locally declining. This overlap occurs particularly in habitats undergoing natural and anthropogenic modification. The objective of our study was to determine the respective effects of habitat changes and climatic conditions on fisher and marten populations in Quebec, Canada, based on trapper knowledge. We analyzed annual fisher and marten harvest (number of pelts sold/100 km2) between the 1984–1985 and 2014–2015 trapping seasons using linear mixed models. Fisher harvest increased with the increased abundance of mixed forests >12 m tall, resulting from decades of forest harvesting. Fisher harvest decreased with increasing spring rains, which can affect survival when rearing young. Marten harvest decreased with increasing winter rains, which lower thermoregulation capacity and hamper movements by creating an ice crust on the snowpack, reducing access to subnivean areas. Decline in marten harvest during the 30-year study period coincided with an increase in fisher harvest, suggesting possible interspecific competition. Results highlight that managers should strive to maintain mixedwood stands taller than 12 m to maintain high quality habitat for fishers. Our study confirms the importance of working with trappers to assess furbearing population trends in response to habitat changes and climatic conditions. © 2019 The Wildlife Society.  相似文献   

2.
Eurasian pine martens are considered habitat specialists, associated primarily with mature stands of mesic mixed wood forest habitats, and avoid areas without overhead cover The species is found throughout the temperate and boreal regions of the continent but on the Mediterranean island of Minorca, introduced pine martens thrive in a competitor- and predator-free environment I test the prediction that because of evolved prey-capture and predator avoidance strategies Minorcan martens should select habitats most similar to temperate and northern parts of their range Scat index routes were used to quantify pine marten habitat selection Marten did not demonstrate any habitat type preferences although observed use of pine forests and coastal shrublands was slighly greater than expected Marten were indifferent to overhead cover whereas mesic sites and areas of tall high shrub density were favored Small mammal trap indices and preferred prey suggested that martens commonly used non-forested areas My results demonstrated that on Minorca pine martens were habitat generalists In the absence of predators open non-forested habitats were equally important to pine marten as were forested ones  相似文献   

3.
Evaluating presence and abundance of small carnivores is essential for their conservation. In Italy, there is scarce information on European pine marten distribution, and no data are published on its abundance. Camera traps have been widely used to estimate population density applying capture–recapture models for species in which individual recognition is possible. Here we estimate the abundance of European pine martens in central Italy using camera trapping and a model that allows the estimation of population density without the need for individual recognition Rowcliffe et al. (Anim Conserv 11:185–186, 2008). Camera trapping was also used to evaluate habitat use patterns by martens. Fifteen camera traps were deployed in 90 placements for 15 days each, for a total of 1,334 camera days. Pine martens were captured in 24% of camera trap placements with a mean trap success rate of 0.33 photographs per camera placement. Estimated pine marten population density in the study area was 0.34 individuals km−2. Marten trap rate was not strongly associated with any habitat type, although there were trends towards lower probability of records at locations with high coverage of cultivated fields and higher probability of records at locations with high coverage of human-made woodland. The results suggest that pine martens in this area are not confined to wooded habitat. To our knowledge, this study is the first application of the Rowcliffe et al. (Anim Conserv 11:185–186, 2008) method to a wild carnivore population and, furthermore, the first estimation of population density of pine martens in Italy.  相似文献   

4.
BackgroundHepatitis A is a common acute hepatitis caused by hepatitis A virus (HAV). Annually, it affects 1.4 million people worldwide. Between 1991 and 1994, HAV infections were highly endemic in Zhejiang Province (China), with 78,720 reported HAV infections per year. Hepatitis A vaccine came on the market in 1995 and was implemented for voluntary immunization. Since 2008, hepatitis A vaccine has been integrated into the national childhood routine immunization program.ObjectiveTo understand the current epidemiological profile of hepatitis A in Zhejiang Province since hepatitis A vaccine has been available for nearly two decades.MethodsThis study used the 2005–2014 National Notifiable Diseases Reporting System data to evaluate the incidence rate of notified hepatitis A cases in Zhejiang Province.ResultsThe overall trend of incidence rate of notified hepatitis A cases significantly decreased from 2005 to 2014 (P< 0.001). During the study period, the reported incidence rate in individuals aged ≤19 years declined to the historically lowest record in 2014. Compared with individuals aged ≤19 years, those aged ≥20 years showed the highest incidence rate (P< 0.001). Majority of HAV infected cases were Laborers, accounting for approximately 70% of reported cases.ConclusionsChildhood immunization strategy with hepatitis A vaccine seemed to be effective in decreasing notified hepatitis A incidence rate in individuals aged ≤19 years. Those aged ≥20 years were observed to be the most susceptible population. The vast majority of hepatitis A cases were notified among Laborers. Therefore, we strongly suggest that future preventive and control measures should focus more on adults, particularly Laborers, in addition to the current childhood hepatitis A vaccination programme.  相似文献   

5.
One hundred cases of hypophosphataemia (≤ 2·0 mg/100 ml) and 84 cases of hyperphosphataemia (≥ 5·0 mg/100 ml) occurring in a hospital population were studied in order to determine the cause of the abnormality. Examples of hyperphosphataemia due to renal failure were excluded from the study.A low serum phosphorus concentration was most frequently due to intravenous administration of carbohydrate, usually glucose, which accounted for 40% of cases. The next commonest cause was vomiting (12%). No obvious explanation could be found in 26% of cases, but in most of these factors were present which are known to affect phosphorus metabolism.No one cause of hyperphosphataemia was outstanding in frequency and in over 50% of cases no definite explanation for the abnormality could be found.  相似文献   

6.
The controversial data about antral follicle count (AFC) may be partially explained by the different criteria used to determine what is high, intermediate and low AFC. This study evaluated different classification methods for AFC groups, relating them to the conception rate, dominant follicle size and body condition score (BCS) in cows submitted to timed artificial insemination (TAI). Nelore cows (Bos indicus; n = 935), received a reproductive program consisting of TAI and natural breeding. Conception rate, BCS and dominant follicle size during TAI were evaluated by three AFC methodologies: i) mean and standard deviation: low (≤ 15 follicles); intermediate (≥ 16 to ≤ 44 follicles) or high (≥ 45 follicles); ii) quartiles: low (≤ 15 follicles); intermediate (≥ 16 to ≤ 39 follicles), or high (≥ 40 follicles); and iii) AFC score: I (low; ≤ 15 follicles); II (intermediate; ≥ 16 to ≤ 30 follicles); III (high; ≥ 31 to ≤ 44 follicles) or IV (very high; ≥ 45 follicles). Data were analyzed by a GLIMMIX and Tukey test or binary logistic regression model (P ≤ 0.05). The conception rate to TAI was influenced (P < 0.05) by AFC in the three methods classification, being the highest conception rate observed in the low AFC group regardless of method utilized: Mean (low 61.73%a, intermediate 54.02%ab and high 49.48%b), Quartiles (low 61.73%a, intermediate 53.59%ab and 51.46%b) and Score (I 61.73%a, II 54.80%ab, III 53.23%ab and IV 49.48%b). There were variations (P < 0.05) in the conception rate within the 2.50 to 2.75 BCS range for all AFC classification methods, with the low AFC females presenting the best results, regardless of the method used. Also, females with low AFC showed larger (P < 0.05) diameters of dominant follicles at the TAI regardless of method. The different methodologies used (Mean, Quartile and Score) to AFC classification showed a consistency between the main findings, and we believe that this standardization will facilitate the interpretation of data involving AFC.  相似文献   

7.
Food habits of three sympatric carnivore mammals in the Tsushima islands of Japan were studied during 1986–91. Scats of the Tsushima marten (n=1236), the Siberian weasel (n=218) and the Tsushima leopard cat (n=350) were collected monthly and the food items were determined by scat contents analysis. Marten was omnivorous showing a high level of diversity of food throughout the year. The important foods for marten were fruits and berries from spring to autumn, insects in summer and autumn and small mammals all year round. Leopard cat preferred to hunt wood/mice and birds, and remained a flesh meat specialist throughout the year. Weasel was intermediate between marten and leopard cat, but was slightly biased towards the flesh meat eater. The three carnivores do not compete against one another for food, except for small rodents. A conflict for food between leopard cat and weasel was suggested to be more intense than that of other combinations based on diet overlapping. Marten may be characterized as an opportunistic generalist. When interspecific competitors existed, or human disturbance to the habitat occurred, the preferential flexibility of the marten to alternative food resources might become more advantageous than the other two species.  相似文献   

8.

Background

Perinatal or mother-to-child transmission of hepatitis B virus (HBV) results in a high frequency of chronic infection. Risk of mother-to-child transmission is associated with maternal viral factors including hepatitis B e antigen (HBeAg) positivity and viral load.

Aim

To investigate associations between age, HBeAg status, HBV DNA levels and genotype in female patients screened for inclusion into two contemporary, randomized HBV trials.

Methods

Retrospective analyses focused on differences between women of childbearing age (≤44 years) and older women. Female patients (N = 355; 18–69 years) were included in the analysis: 41.7% of patients were Asian. In total, 44.4% were HBeAg-positive.

Results

Significantly more women aged ≤44 years were HBeAg-positive compared to women ≥45 years (57.2% versus 27.5%, respectively, p<0.0001), this proportion declined with increasing age. Younger women were significantly more likely to have high HBV viral load (HBV DNA>108 copies mL: ≤44 years 46.0% vs ≥45 years 25.5%, respectively; p<0.0001), and this declined with increasing age. HBeAg positivity was slightly higher in Asian women, associated with a higher proportion of HBV genotypes B and C in this population. There was no obvious relationship between genotype and viral load.

Conclusions

Women of childbearing age with CHB are more likely to have high HBV viral load and HBeAg positivity than older women; this likelihood decreases with age. Maternal serological and virological status should therefore be established early in pregnancy, taking into account age and genotype, and a risk-reducing strategy implemented in any patient who is HBeAg positive and has a high viral load.  相似文献   

9.
Microinjecting DNA into the cytoplasm of the syncytial gonad of Caenorhabditis elegans is the main technique used to establish transgenic lines that exhibit partial and variable transmission rates of extrachromosomal arrays to the next generation. In addition, transgenic animals are mosaic and express the transgene in a variable number of cells. Extrachromosomal arrays can be integrated into the C. elegans genome using UV irradiation to establish nonmosaic transgenic strains with 100% transmission rate of the transgene. To that extent, F1 progenies of UV irradiated transgenic animals are screened for animals carrying a heterozygous integration of the transgene, which leads to a 75% Mendelian transmission rate to the F2 progeny. One of the challenges of this method is to distinguish between the percentage of transgene transmission in a population before (X% transgenic animals) and after integration (≥75% transgenic F2 animals). Thus, this method requires choosing a nonintegrated transgenic line with a percentage of transgenic animals that is significantly lower than the Mendelian segregation of 75%. Consequently, nonintegrated transgenic lines with an extrachromosomal array transmission rate to the next generation ≤60% are usually preferred for integration, and transgene integration in highly transmitting strains is difficult. Here we show that the efficiency of extrachromosomal arrays integration into the genome is increased when using highly transmitting transgenic lines (≥80%). The described protocol allows for easy selection of several independent lines with homozygous transgene integration into the genome after UV irradiation of transgenic worms exhibiting a high rate of extrachromosomal array transmission. Furthermore, this method is quite fast and low material consuming. The possibility of rapidly generating different lines that express a particular integrated transgene is of great interest for studies focusing on gene expression pattern and regulation, protein localization, and overexpression, as well as for the development of subcellular markers.  相似文献   

10.
Co‐occurring species are rarely considered as a factor influencing habitat selection. However, niche theory predicts that sharing resources, predators, and other interspecific interactions can limit the environmental conditions under which a species may exist. How does the spatial distribution of one species affect that of another within shared landscapes? We tested whether sympatric marten Martes americana and fishers M. pennanti in a mountain landscape in Alberta, Canada exhibit local‐scale spatial segregation, beyond differential habitat selection. We modelled marten and fisher distribution in relation to remotely‐sensed habitat data and species co‐occurrence, using generalized linear models and information‐theoretic model selection. Marten and fishers selected different habitat types and showed different responses to habitat fragmentation. Even after accounting for these differences, the absence of one species significantly explained the occurrence of the other. We conclude that the spatial distribution of marten and fishers influences habitat selection by each other at landscape scales, and hypothesize that this pattern may result from competition in a spatially heterogeneous environment. Species‐habitat models that consider only resources may fail to capture key predictors of species’ occurrence. Reliable prediction and inference requires that ecologists expand from landscapes to also include species‐scapes: a spatial plane of species interactions that combines with resources to drive species’ distributions.  相似文献   

11.
To assess niche overlap between the most similar European sympatric carnivores, the pine marten Martes martes and stone marten Martes foina, and outline their potential distributions and connectivity corridors in Central Italy, we applied a multivariate kernel density procedure which allowed to assess both species' ecological hypervolumes based on a set of 16 environmental predictors and used the resulting probability of occurrence map as a resistance surface in electrical circuit theory-based models. Distance to watercourses and percent cover of deciduous forest and shrubland were the most relevant factors shaping pine marten ecological niche, while stone marten distribution was mainly shaped by human population density and cover of both human settlements and deciduous forest. Overlap between the hypervolumes of the two martens was low-to-moderate, while, on average, landscape connectivity was higher for the stone marten. The inclusion in the models of human disturbance-related variables enabled to define a possible mechanism driving habitat partitioning in human-altered landscapes. Based on our results, increasing human density and urbanization of European lowland and hilly landscapes are expected to represent a greater threat to the pine marten than the stone marten.  相似文献   

12.
AimTo determine the optimal cut-off value of serum total adiponectin for managing the risk of developing metabolic syndrome (MetS) in male Japanese workers.MethodsA total of 365 subjects without MetS aged 20–60 years were followed up prospectively for a mean of 3.1 years. The accelerated failure-time model was used to estimate time ratio (TR) and cut-off value for developing MetS.ResultsDuring follow-up, 45 subjects developed MetS. Age-adjusted TR significantly declined with decreasing total adiponectin level (≤ 4.9, 5.0–6.6, 6.7–8.8 and ≥ 8.9 μg/ml, P for trend = 0.003). In multivariate analyses, TR of MetS was 0.12 (95% CI 0.02–0.78; P = 0.03) in subjects with total adiponectin level of 5.0–6.6 μg/ml, and 0.15 (95% CI 0.02–0.97; P = 0.047) in subjects with total adiponectin level ≤ 4.9 μg/ml compared with those with total adiponectin level ≥ 8.9 μg/ml. The accelerated failure-time model showed that the optimal cut-off value of total adiponectin for managing the risk of developing MetS was 6.2 μg/ml. In the multivariate-adjusted model, the mean time to the development of MetS was 78% shorter for total adiponectin level ≤ 6.2 μg/ml compared with > 6.2 μg/ml (TR 0.22, 95% CI: 0.08–0.64, P = 0.005).ConclusionOur findings suggest that the cut-off value for managing the risk of developing MetS is 6.2 μg/ml in male Japanese workers. Subjects with total adiponectin level ≤ 6.2 μg/ml developed MetS more rapidly than did those with total adiponectin level > 6.2 μg/ml.  相似文献   

13.
We compared the distribution and frequency of American marten (Martes americana) detections during historic surveys and a recent survey on the Sagehen Experimental Forest (SEF) in the Sierra Nevada Mountains, California. This area has been the location of 9 previous marten surveys during 1980–1993, each involving a systematic detection/non-detection survey on the same grid. These data are a time series of information on the occupancy of martens that can be related to habitat change in the study area. Our objectives were to 1) resurvey martens in SEF using methodology similar to previous studies to assess current marten occupancy; 2) evaluate changes in marten occupancy during the period 1980–2008; and 3) examine associations between marten occurence and changes in habitat and landscape metrics. Current marten occupancy was estimated using surveys conducted in summer 2007, winter 2007–2008, and summer 2008. From 1978 to 2007 there was a decrease in predicted habitat patch size, core area, and total amount of marten habitat in the study area, as well as an increase in distance between patches. Marten detections in 2007–2008 were approximately 60% lower than in surveys in the 1980s. We detected no martens in the summers of 2007 and 2008, and 10 detections in winter 2007–2008 were limited to higher elevations in the southwestern portion of SEF. No martens were detected in the lower elevations where most of the recent forest management activity occurred. We suggest that the marten population at SEF has been negatively affected by the loss and fragmentation of habitat. We recommend that future management of forests in the Sagehen basin focus on restoring and connecting residual marten habitat to improve habitat quality for martens. © 2011 The Wildlife Society.  相似文献   

14.

Objectives

To evaluate the impact of glycemic control of diabetes mellitus (DM) on prostate cancer detection in a biopsy population.

Patients and Methods

We retrospectively reviewed the records of 1,368 men who underwent prostate biopsy at our institution. We divided our biopsy population into three groups according to their history of DM, and their Hemoglobin A1c (HbA1c) level: a no-DM (DM−) group; a good glycemic control (DM+GC) group (HbA1c <6.5%); and a poor glycemic control (DM+PC) group (HbA1c ≥6.5%). For sub-analyses, the DM+PC group was divided into a moderately poor glycemic control (DM+mPC) group (6.5≤ HbA1c <7.5%) and a severely poor glycemic control (DM+sPC) group (HbA1c ≥7.5%).

Results

Among 1,368 men, 338 (24.7%) had a history of DM, and 393 (28.7%) had a positive biopsy. There was a significant difference in prostatic specific antigen density (PSAD) (P = 0.037) and the frequency of abnormal DRE findings (P = 0.031) among three groups. The occurrence rate of overall prostate cancer (P<0.001) and high-grade prostate cancer (P = 0.016) also presented with a significantly difference. In the multivariate analysis, the DM+PC group was significantly associated with a higher rate of overall prostate cancer detection in biopsy subjects compared to the DM− group (OR = 2.313, P = 0.001) but the DM+PC group was not associated with a higher rate of high-grade (Gleason score ≥7) diseases detected during the biopsy (OR = 1.297, P = 0.376). However, in subgroup analysis, DM+sPC group was significantly related to a higher risk of high-grade diseases compared to the DM− group (OR = 2.446, P = 0.048).

Conclusions

Poor glycemic control of DM was associated with a higher risk of prostate cancer detection, including high-grade disease, in the biopsy population.  相似文献   

15.

Background

The Platelia Aspergillus Ag assay (Bio-Rad) is designed for detecting Aspergillus galactomannan (GM) and is widely used for diagnosing invasive aspergillosis but is hampered by variable occurrences of unreproducible positive results. Frequency and origin of these unreproducible results have not been formally studied.

Methods

Different technicians simultaneously performed four tests on 550 consecutive sera from adult patients (Test#1-Test#2 for extraction#1 and Test#3-Test#4 for extraction#2). The samples were classified as confirmed negative [all tests with GM optical density index (GM-ODI) <0.5], confirmed positive (all tests with GM-ODI ≥0.5), extraction unreproducible positive (Test#1 and Test#2 ODIs ≥0.5, and Test#3 and Test#4 GM-ODIs <0.5, or conversely), and ELISA unreproducible positive (only one test with GM-ODI ≥0.5). The samples with positive and negative GM-ODIs within the assay coefficient of variation values were classified as non-conclusive. Four similar additional tests were performed after ≤72h storage at 4°C and a new GM test after 8 months at -20°C.

Results

Five-hundred-twenty sera (94.5%) were confirmed negative, 15 (2.7%) confirmed positive, 4 (0.7%) extraction unreproducible positive, 6 (1.1%) ELISA unreproducible positive, and 5 (0.9%) non-conclusive. Upon retesting, the unreproducible positive results turned negative except for one which turned non-conclusive. The confirmed positive and non-conclusive had similar GM-ODIs (p>0.4) upon retesting after storage ≤72h at 4°C (n = 20) or eight months at -20°C (n = 17).

Conclusions

Operational unreproducible positives represent 33% of the GM-positive results and a second sample evaluation appears mandatory to avoid useless investigations or treatments. When operational artifacts are excluded, GM remains stable at standard storage conditions.  相似文献   

16.

Background

We previously found that a very low geno2pheno false positive rate (FPR ≤2%) defines a viral population associated with low CD4 cell count and the highest amount of X4-quasispecies. In this study, we aimed at evaluating whether FPR ≤2% might impact on the viro-immunological response in HIV-1 infected patients starting a first-line HAART.

Methods

The analysis was performed on 305 HIV-1 B subtype infected drug-naïve patients who started their first-line HAART. Baseline FPR (%) values were stratified according to the following ranges: ≤2; 2–5; 5–10; 10–20; 20–60; >60. The impact of genotypically-inferred tropism on the time to achieve immunological reconstitution (a CD4 cell count gain from HAART initiation ≥150 cells/mm3) and on the time to achieve virological success (the first HIV-RNA measurement <50 copies/mL from HAART initiation) was evaluated by survival analyses.

Results

Overall, at therapy start, 27% of patients had FPR ≤10 (6%, FPR ≤2; 7%, FPR 2–5; 14%, FPR 5–10). By 12 months of therapy the rate of immunological reconstitution was overall 75.5%, and it was significantly lower for FPR ≤2 (54.1%) in comparison to other FPR ranks (78.8%, FPR 2–5; 77.5%, FPR 5–10; 71.7%, FPR 10–20; 81.8%, FPR 20–60; 75.1%, FPR >60; p = 0.008). The overall proportion of patients achieving virological success was 95.5% by 12 months of therapy. Multivariable Cox analyses showed that patients having pre-HAART FPR ≤2% had a significant lower relative adjusted hazard [95% C.I.] both to achieve immunological reconstitution (0.37 [0.20–0.71], p = 0.003) and to achieve virological success (0.50 [0.26–0.94], p = 0.031) than those with pre-HAART FPR >60%.

Conclusions

Beyond the genotypically-inferred tropism determination, FPR ≤2% predicts both a poor immunological reconstitution and a lower virological response in drug-naïve patients who started their first-line therapy. This parameter could be useful to identify patients potentially with less chance of achieving adequate immunological reconstitution and virological undetectability.  相似文献   

17.
Glycated hemoglobin (HbA1c) is an important diagnostic indicator of diabetes mellitus, and some authors have argued that it is related to impaired lung function in the diabetic population. However, there was rare study for association between lung function and HbA1c in the non-diabetic population. We investigated whether HbA1c below the diagnostic threshold is related to deficits in lung function. We analyzed biochemical and spirometry data from a nation-wide, population-based, case-control study (the KNHANES IV and V). Eligible as cases were all native Koreans aged 40 years or more with no medical illness. A total of 3670 participants were divided into 4 groups according to HbA1c (%) as follows: Group I (n = 842), ≥ 4.0 and ≤ 5.3; Group II (n = 833), > 5.3 and ≤ 5.5; Group III (n = 898), > 5.5 and ≤ 5.7; and Group IV (n = 1097), > 5.7 and ≤ 6.4. Group I had the greatest forced vital capacity (FVC, 96.3 ± 0.5% pred, P < 0.0001), forced expiratory volume per second (FEV1, 93.8 ± 0.5% pred, P < 0.0001) and FEV1/FVC (0.792 ± 0.003, P < 0.0001) compared with the other groups. Linear regression showed that HbA1c was closely related to FVC (β = -6.972154, P < 0.0001) and FEV1 (β = -5.591589, P < 0.0001), but not to FEV1/FVC. Logistic regression analysis revealed a significant association between HbA1c and a restrictive spirometric pattern (FVC < 80% pred., FEV1/FVC ≥ 0.70; OR = 3.772, 95% CI = 1.234-11.53), indicating that elevated HbA1c is closely associated with lung impairment in the non-diabetic population. In the healthy population, relatively high HbA1c level is associated with decrements of FVC and FEV1 and may be a reliable predictor of poor lung function, especially the restrictive pattern.  相似文献   

18.

Objective

To define accelerometer cut points for different walking speeds in older adults with mild to moderate Parkinson’s disease.

Method

A volunteer sample of 30 older adults (mean age 73; SD 5.4 years) with mild to moderate Parkinson’s disease walked at self-defined brisk, normal, and slow speeds for three minutes in a circular indoor hallway, each wearing an accelerometer around the waist. Walking speed was calculated and used as a reference measure. Through ROC analysis, accelerometer cut points for different levels of walking speed in counts per 15 seconds were generated, and a leave-one-out cross-validation was performed followed by a quadratic weighted Cohen’s Kappa, to test the level of agreement between true and cut point–predicted walking speeds.

Results

Optimal cut points for walking speeds ≤ 1.0 m/s were ≤ 328 and ≤ 470 counts/15 sec; for speeds > 1.3 m/s, they were ≥ 730 and ≥ 851 counts/15 sec for the vertical axis and vector magnitude, respectively. Sensitivity and specificity were 61%–100% for the developed cut points. The quadratic weighted Kappa showed substantial agreement: κ = 0.79 (95% CI 0.70–0.89) and κ = 0.69 (95% CI 0.56–0.82) for the vertical axis and the vector magnitude, respectively.

Conclusions

This study provides accelerometer cut points based on walking speed for physical-activity measurement in older adults with Parkinson’s disease for evaluation of interventions and for investigating links between physical activity and health.  相似文献   

19.
Vegetated buffer strips were evaluated for their ability to remove waterborne Cryptosporidium parvum from surface and shallow subsurface flow during simulated rainfall rates of 15 or 40 mm/h for 4 h. Log10 reductions for spiked C. parvum oocysts ranged from 1.0 to 3.1 per m of vegetated buffer, with buffers set at 5 to 20% slope, 85 to 99% fescue cover, soil textures of either silty clay (19:47:34 sand-silt-clay), loam (45:37:18), or sandy loam (70:25:5), and bulk densities of between 0.6 to 1.7 g/cm3. Vegetated buffers constructed with sandy loam or higher soil bulk densities were less effective at removing waterborne C. parvum (1- to 2-log10 reduction/m) compared to buffers constructed with silty clay or loam or at lower bulk densities (2- to 3-log10 reduction/m). The effect of slope on filtration efficiency was conditional on soil texture and soil bulk density. Based on these results, a vegetated buffer strip comprised of similar soils at a slope of ≤20% and a length of ≥3 m should function to remove ≥99.9% of C. parvum oocysts from agricultural runoff generated during events involving mild to moderate precipitation.  相似文献   

20.
A variety of filters assays have been described to enrich circulating tumor cells (CTC) based on differences in physical characteristics of blood cells and CTC. In this study we evaluate different filter types to derive the properties of the ideal filter for CTC enrichment. Between 0.1 and 10 mL of whole blood spiked with cells from tumor cell lines were passed through silicon nitride microsieves, polymer track-etched filters and metal TEM grids with various pore sizes. The recovery and size of 9 different culture cell lines was determined and compared to the size of EpCAM+CK+CD45−DNA+ CTC from patients with metastatic breast, colorectal and prostate cancer. The 8 µm track-etched filter and the 5 µm microsieve had the best performance on MDA-231, PC3-9 and SKBR-3 cells, enriching >80% of cells from whole blood. TEM grids had poor recovery of ∼25%. Median diameter of cell lines ranged from 10.9–19.0 µm, compared to 13.1, 10.7, and 11.0 µm for breast, prostate and colorectal CTC, respectively. The 11.4 µm COLO-320 cell line had the lowest recovery of 17%. The ideal filter for CTC enrichment is constructed of a stiff, flat material, is inert to blood cells, has at least 100,000 regularly spaced 5 µm pores for 1 ml of blood with a ≤10% porosity. While cell size is an important factor in determining recovery, other factors must be involved as well. To evaluate a filtration procedure, cell lines with a median size of 11–13 µm should be used to challenge the system.  相似文献   

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