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21.
At times, total dissolved gas concentrations in the Columbia and Snake rivers have been elevated due to involuntary spill from high spring runoff and voluntary spill used as a method to pass juvenile salmonids over dams. The goal of this project was to determine if acute exposure to total dissolved gas supersaturation (TDGS) affects the reproductive performance of female chinook salmon late in their maturation. During this study, adult female spring chinook salmon were exposed to mean TDGS levels of 114.1% to 125.5%. We ended exposures at first mortality, or at the appearance of impending death. Based on this criterion, exposures lasted from 10 to 68 h and were inversely related to TDGS. There was no effect of TDGS on pre‐spawning mortality or fecundity when comparing treatment fish to experimental controls or the general hatchery population four to six weeks after exposures. Egg quality, based on egg weight and egg diameter, did not differ between treatment and control fish. Fertilization rate and survival to eyed‐stage was high ( > 94%) for all groups. With the exception of Renibacterium salmoninarum (the causative agent of bacterial kidney disease; BKD), no viral or bacterial fish pathogens were isolated from experimental fish. The prevalence (about 45%) and severity of R. salmoninarum did not differ among the groups or the general hatchery population. We conclude that these acute exposures to moderate levels of gas‐supersaturated water—perhaps similar to that experienced by immigrating adult salmon as they approach and pass a hydropower dam on the Columbia River—did not affect reproductive success of female chinook salmon late in their maturation. These results are most applicable to summer and fall chinook salmon, which migrate in the summer/fall and spawn shortly after reaching their natal streams. Published in 2004 by John Wiley & Sons, Ltd. 相似文献
22.
In vivo measurement of swallowing by monitoring thyroid cartilage movement in healthy subjects using thickened liquid samples and its comparison with sensory evaluation 下载免费PDF全文
23.
《Ergonomics》2012,55(8):871-880
Work-related chronic injuries occur in muscles, tendons, and nerves. Epidemiological, histological, and physiological data confirm their often disputed physical basis. Terms such as repetitive strain injury and cumulative trauma disorder, when used as a diagnosis, have obscured the issue for they are really statements of causation. Definitive diagnosis is required both to treat and prevent such injuries. Precise terminology that identifies the tissue and its pathology is required. A detailed assessment methodology is described that allows a precise diagnosis. A clear relationship to work stress is necessary both to establish the cause and formulate prevention strategies. Treatment must begin early and be appropriate to the tissue and the nature of the injury. Examples are presented and discussed. Early treatment begins before too much damage has been done and yields better results. 相似文献
24.
The objective of this study was to evaluate the risk of musculoskeletal injuries in a banana processing task. A sample of three workers were evaluated with the Nordic questionnaire as well as according to effort, discomfort and usability levels, hand grip dynamometry, inertial sensor motion capture (Xsens) and surface electromyography in the right arm. The workers had musculoskeletal complaints throughout the spine and hips, low effort and discomfort levels, and a satisfactory usability level. The hand grip strength values (dominant: 54.8 Kgf; non-dominant: 54.2 Kgf) were above the reference values for the Brazilian population. Regarding movement analysis, we identified risks related to cervical protrusion, forward and lateral trunk flexion, abduction and flexion in the shoulders, flexion, extension, radial and ulnar deviation in the wrists, as well as repetitive movements. Surface electromyography showed that the greatest demand during the task was on the extensor carpi radialis, although the trapezius and flexor carpi radialis showed a tendency toward fatigue. Thus, the set of evaluations showed that the tool used and worker adaptation to the position of the bunches, together with the repetitious movement, led to inadequate postures and musculoskeletal risks.Relevance to industryThe banana processing activity generates employment and income in several regions of the world and in Brazil. However, it is still rudimentary and may present risks to the worker's health. This study seeks to elucidate ergonomic risks through technological instrumentation in order to have a quantitative assessment of the ergonomic risks. 相似文献
25.
Blake Fitzpatrick 《History of Photography》2013,37(2):176-187
This article examines the recirculation of Robert Del Tredici's photographs of the Cold War nuclear weapons complex. Originally published in his groundbreaking book, At Work in the Fields of the Bomb (1987), a number of Del Tredici's photographs have been republished in a series of post‐Cold War US Department of Energy reports. The article examines the post‐Cold War circulation of Del Tredici's images in these official government reports and analyzes shifts in their meaning across different historical periods. Ultimately, this paper raises questions about the critical stance of Del Tredici's photographs as they are republished in government reports and examines ways in which the meaning of his photographs responds to both Cold War and post‐Cold War contexts. 相似文献
26.
Spatial and temporal changes of subchondral bone proceed to articular cartilage degeneration in rats subjected to knee immobilization 下载免费PDF全文
Lei Xu Zhe Li Lei Lei Yue‐Zhu Zhou Song‐Yun Deng Yong‐Bin He Guo‐Xin Ni 《Microscopy research and technique》2016,79(3):209-218
This study was aimed to investigate the spatial and temporal changes of subchondral bone and its overlying articular cartilage in rats following knee immobilization. A total of 36 male Wistar rats (11–13 months old) were assigned randomly and evenly into 3 groups. For each group, knee joints in 6 rats were immobilized unilaterally for 1, 4, or 8 weeks, respectively, while the remaining rats were allowed free activity and served as external control groups. For each animal, femurs at both sides were dissected after sacrificed. The distal part of femur was examined by micro‐CT. Subsequently, femoral condyles were collected for further histological observation and analysis. For articular cartilage, significant changes were observed only at 4 and 8 weeks of immobilization. The thickness of articular cartilage and chondrocytes numbers decreased with time. However, significant changes in subchondral bone were defined by micro‐CT following immobilization in a time‐dependent manner. Immobilization led to a thinner and more porous subchondral bone plate, as well as a reduction in trabecular thickness and separation with a more rod‐like architecture. Changes in subchondral bone occurred earlier than in articular cartilage. More importantly, immobilization‐induced changes in subchondral bone may contribute, at least partially, to changes in its overlying articular cartilage. Microsc. Res. Tech. 79:209–218, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
27.
Jina Ryu Mats Brittberg Bomi Nam Jinyeong Chae Minju Kim Yhan Colon Iban Martin Magneli Eiji Takahashi Bharti Khurana Charles R. Bragdon 《International journal of molecular sciences》2022,23(5)
Cartilage lesions are difficult to repair due to low vascular distribution and may progress into osteoarthritis. Despite numerous attempts in the past, there is no proven method to regenerate hyaline cartilage. The purpose of this study was to investigate the ability to use a 3D printed biomatrix to repair a critical size femoral chondral defect using a canine weight-bearing model. The biomatrix was comprised of human costal-derived cartilage powder, micronized adipose tissue, and fibrin glue. Bilateral femoral condyle defects were treated on 12 mature beagles staged 12 weeks apart. Four groups, one control and three experimental, were used. Animals were euthanized at 32 weeks to collect samples. Significant differences between control and experimental groups were found in both regeneration pattern and tissue composition. In results, we observed that the experimental group with the treatment with cartilage powder and adipose tissue alleviated the inflammatory response. Moreover, it was found that the MOCART score was higher, and cartilage repair was more organized than in the other groups, suggesting that a combination of cartilage powder and adipose tissue has the potential to repair cartilage with a similarity to normal cartilage. Microscopically, there was a well-defined cartilage-like structure in which the mid junction below the surface layer was surrounded by a matrix composed of collagen type I, II, and proteoglycans. MRI examination revealed significant reduction of the inflammation level and progression of a cartilage-like growth in the experimental group. This canine study suggests a promising new surgical treatment for cartilage lesions. 相似文献
28.
Claire S. Whyte Akriti Rastogi Ellis Ferguson Michela Donnarumma Nicola J. Mutch 《International journal of molecular sciences》2022,23(6)
Loss of fibrinogen is a feature of trauma-induced coagulopathy (TIC), and restoring this clotting factor is protective against hemorrhages. We compared the efficacy of cryoprecipitate, and of the fibrinogen concentrates RiaSTAP® and FibCLOT® in restoring the clot integrity in models of TIC. Cryoprecipitate and FibCLOT® produced clots with higher maximal absorbance and enhanced resistance to lysis relative to RiaSTAP®. The fibrin structure of clots, comprising cryoprecipitate and FibCLOT®, mirrored those of normal plasma, whereas those with RiaSTAP® showed stunted fibers and reduced porosity. The hemodilution of whole blood reduced the maximum clot firmness (MCF) as assessed by thromboelastography. MCF could be restored with the inclusion of 1 mg/mL of fibrinogen, but only FibCLOT® was effective at stabilizing against lysis. The overall clot strength, measured using the Quantra® hemostasis analyzer, was restored with both fibrinogen concentrates but not cryoprecipitate. α2antiplasmin and plasminogen activator inhibitor-1 (PAI-1) were constituents of cryoprecipitate but were negligible in RiaSTAP® and FibCLOT®. Interestingly, cryoprecipitate and FibCLOT® contained significantly higher factor XIII (FXIII) levels, approximately three-fold higher than RiaSTAP®. Our data show that 1 mg/mL fibrinogen, a clinically achievable concentration, can restore adequate clot integrity. However, FibCLOT®, which contained more FXIII, was superior in normalizing the clot structure and in stabilizing hemodiluted clots against mechanical and fibrinolytic degradation. 相似文献
29.
Batten Sonja V.; Drapalski Amy L.; Decker Melissa L.; DeViva Jason C.; Morris Lorie J.; Mann Mark A.; Dixon Lisa B. 《Canadian Metallurgical Quarterly》2009,6(3):184
[Correction Notice: An erratum for this article was reported in Vol 7(3) of Psychological Services (see record 2010-17074-004). The copyright for the article was listed incorrectly. This article is in the Public Domain. The online version has been corrected.] The present study examined interest in family involvement in treatment and preferences concerning the focus of family oriented treatment for veterans (N = 114) participating in an outpatient Veterans Affairs outpatient posttraumatic stress disorder (PTSD) program. Most veterans viewed PTSD as a source of family stress (86%) and expressed interest in greater family involvement in their treatment (79%). These results suggest the need to consider increasing family participation in the clinical care of individuals with PTSD and to develop specialized family educational and support services for this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Research indicates that trauma is extremely prevalent among populations seeking community-based services. However, underdiagnosis and nontreatment of trauma-related disorders is widespread. This study explored how one urban community mental health center (CMHC), serving a severely mentally ill (SMI) population, assessed, diagnosed, and treated reported trauma histories. Results indicate that of the 72 consumers in this sample who reported trauma histories (51%), only 2 were diagnosed with posttraumatic stress disorder (PTSD). Instead, those with a reported trauma history were likely to be diagnosed with affective disorders and were almost seven times as likely to be recommended therapy as were those without a trauma history. However, even those recommended therapy were not likely to receive it. Findings indicate significant barriers to PTSD diagnoses and the receipt of therapy services. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献