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521.
Shimabukuro VG Alexandre NM Coluci MZ Rosecrance JC Gallani MC 《International journal of occupational safety and ergonomics》2012,18(1):15-26
Physical therapists engage in work tasks that expose them to occupational risk factors related to musculoskeletal disorders. Due to the gap in the literature on instruments focused on those workers, this study adapted a job factors questionnaire to physical therapists, and assessed its psychometric properties. The questionnaire was adapted and its content validity was established. The psychometric properties were evaluated among 142 physical therapists. Reliability was verified using the temporal-stability design and internal consistency. Construct validity was assessed with the known-groups technique. Test-retest results demonstrated intraclass correlation coefficients between .82 and .90 (p < .001). Cronbach's α of .91 verified the reliability of the questionnaire. The known-groups technique demonstrated a statistically significant difference on the scores of the items when physical therapists were compared to office workers. The results indicated that the adapted questionnaire had acceptable psychometric properties for assessing problematic job factors among physical therapists working in hospitals. 相似文献
522.
Environmental Fluid Mechanics - The flow conditions in and around a suspended canopy, resembling those formed by aquaculture structures such as rafts cages and longlines, were modeled using an... 相似文献
523.
Travis O. Brenden Reneé Reilly Edward Eisch Aaron Switzer Gary E. Whelan 《Environmental monitoring and assessment》2018,190(7):430
Effective water quality management depends on enactment of appropriately designed monitoring programs to reveal current and forecasted conditions. Because water quality conditions are influenced by numerous factors, commonly measured attributes such as total phosphorus (TP) can be highly temporally varying. For highly varying processes, monitoring programs should be long-term and periodic quantitative analyses are needed so that temporal trends can be distinguished from stochastic variation, which can yield insights into potential modifications to the program. Using generalized additive mixed modeling, we assessed temporal (yearly and monthly) trends and quantified other sources of variation (daily and subsampling) in TP concentrations from a multidecadal depth-specific monitoring program on Big Platte Lake, Michigan. Yearly TP concentrations decreased from the late 1980s to late 1990s before rebounding through the early 2000s. At depths of 2.29 to 13.72 m, TP concentrations have cycled around stationary points since the early 2000s, while at the surface and depths ≥?18.29 concentrations have continued declining. Summer and fall peaks in TP concentrations were observed at most depths, with the fall peak at deeper depths occurring 1 month earlier than shallower depths. Daily sampling variation (i.e., variation within a given month and year) was greatest at shallowest and deepest depths. Variation in subsamples collected from depth-specific water samples constituted a small fraction of total variation. Based on model results, cost-saving measures to consider for the monitoring program include reducing subsampling of depth-specific concentrations and reducing the number of sampling depths given observed consistencies across the program period. 相似文献
524.
Buzmakov S. A. Andreev D. N. Nazarov A. V. Dzyuba E. A. Shestakov I. E. Kuyukina M. S. El’kin A. A. Egorova D. O. Khotyanovskaya Yu. V. 《Russian Journal of Ecology》2021,52(4):267-274
Russian Journal of Ecology - Responses to contamination of several soil types with crude oil were comparatively analyzed in organisms of different trophic groups. Samples of soddy podzolic, light... 相似文献
525.
526.
Gabriel N. de O. Teixeira Arthur M. S. da Cruz Gisella R. L. Samanamud Alexandre B. França Luzia L. R. Naves Diego Melo 《Journal of environmental science and health. Part. B》2020,55(1):19-29
AbstractThe main objective of this study is the degradation of a synthetic solution of atrazine by a modified vermiculite catalyzed ozonation, in a rotating packed bed (RPB) reactor. A 0.5?L RPB reactor was used to perform the experiments, using a Central Composite Design (CCD) response surface to construct the quadratic model based on the factors: pH, catalyst concentration and reactor rotation frequency. The response variable was the removal of the organic load measured in terms of Chemical Oxygen Demand (COD). After the complete quadratic model was constructed through the response surface, the COD degradation process had an optimal removal of 41% under the following conditions: pH 8.0, rotation of 1150?rpm and catalyst concentration 0.66?g L?1. 相似文献
527.
Claudia M. Aguilar Jorge Vazquez-Arenas Omar O. Castillo-Araiza Julia L. Rodrguez Isaac Chairez Eric Salinas Tatiana Poznyak 《Environmental science and pollution research international》2020,27(18):22184-22194
The carbamazepine (CBZ) abatement is herein evaluated using catalytic ozonation at different NiO concentrations as catalyst: 100, 300, and 500 mg 相似文献
528.
529.
Low temperature limits the rate of biochemical reactions and aerobic scopes of cold water ectotherms. To compensate for this
limiting effect, animals living in cold environments often possess physiological or morphological adaptations to maintain
vital functions. Cross-latitudinal comparison of aerobic capacities is one method to test which factors constrain activity
in thermally distinct environments particularly when congeneric studies are carried out on related species with conservative
ecology and habitat. Burrowing is a major aerobic activity of bivalve molluscs that is described here for the first time for
the tropical mangrove species Laternula truncata and Laternula boschasina and then compared with their Antarctic congener Laternula elliptica. About 80% of L. truncata (16.3–46.1 mm shell length) and 63% of L. boschasina (11.3–27.7 mm shell length) buried within 24 h at 28°C. The burrowing rate index (BRI = [3√wet weight/time to bury]×104) ranged between 1.1 and 20.2 for L. boschasina and 1.1–32.9 for L. truncata. These values are 2–3 orders of magnitude less than other tropical bivalve molluscs and are amongst the lowest recorded for
any bivalve. Comparisons with the Antarctic L. elliptica showed little or no differences in BRI (Q
10 of 1.0–1.2 for specimens of the same size). This is contrary to the general pattern over a wide range of bivalves, where
BRI increases with a Q
10 of between 2.9 and 6.4 between high latitudes and the equator. L. elliptica has 25–30% longer relative foot length than tropical congeners of the same size, which could be a morphological adaptation
compensating for reduced burrowing speeds in a colder environment. Burrowing rates within the genus Laternula could, however, also be maintained by differing habitat, ecological and physiological constraints on burrowing capability. 相似文献
530.
P. O. Yund 《Marine Biology》1995,122(4):649-654
In marine invertebrate taxa with restricted larval dispersal, the movement of fertilizing sperm may contribute significantly to gene flow. Several recent studies have examined the ability of isolated males to fertilize eggs as a function of distance, but none has explicitly considered the effect of other males in the vicinity on the spatial distribution of fertilizations obtained by a male. I assayed the effect of additional males on the fertilization success of male Botryllus schlosseri (Pallas) colonies with respect to distance via an in situ mating experiment performed in Maine, USA during the summer of 1993. Allozyme markers were used to assay paternity. The presence of additional males reduced the ability of a focal male to fertilize eggs in all distance classes. This suggests that competition for fertilizations among males will reduce gene flow via sperm dispersal and that the fertilization success of isolated males may over-estimate gene flow via sperm dispersal in many natural populations. 相似文献