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Indicated Significant Differences (indicated + significant_difference)
Selected AbstractsLong-term change to fish assemblages and the flow regime in a southeastern U.S. river system after extensive aquatic ecosystem fragmentationECOGRAPHY, Issue 6 2008Christopher M. Taylor The upper Tombigbee River in northeastern Mississippi now exists as a fragment, confluencing with and fed by an extensively modified aquatic landscape now called the Tennessee-Tombigbee Waterway (TTW). We examined the changes to fish assemblages and flow regime after waterway construction based on contemporary comparisons to historical fish collections and discharge data. The river's flow regime has changed markedly since TTW construction. Analysis of discharge data from two stations for 15 years, pre- and post-waterway, indicated significant differences in flow regime including increased minimum and base flows, lower spring and higher late summer-autumn flows, and lower high flow durations, post-TTW. These changes corresponded to significantly reduced regional and local species richness, and strong shifts in fish assemblage structure across a 20 yr time span. Post-waterway fish assemblages were related strongly to measured environmental variables characterizing local habitats. Several lentic-adapted species increased their abundances in lower reaches of the river, including a recent invader to the TTW system, the Mississippi silverside Menidia audens. Fragmentation of river ecosystems via disruption to hydrologic regimes is a major threat to aquatic biodiversity worldwide. Because the flow regime of this fragmented river is in part controlled by waterway operations via five minimum flow control structures, adaptive conservation and management efforts could be implemented in order to maintain and potentially restore the natural flow regime and the ecological integrity of the system. [source] Can circle hook use benefit billfishes?FISH AND FISHERIES, Issue 2 2009Joseph E Serafy Abstract We performed a quantitative review to evaluate circle hook use in recreational and commercial hook-and-line fisheries that interact with billfishes (Family: Istiophoridae). Specifically, we scrutinized the findings of 11 recent empirical studies that reported, on a species-specific basis, side-by-side measures of circle vs. J-hook fishing performance: catch, mortality, deep-hooking and bleeding rates. Of the 30 total comparisons extracted from the literature that satisfied our inclusion criteria, 13 indicated significant differences between hook types for the specific metric compared. No study reported significant billfish catch rate differences between hook types. However, when significant differences between hook types were found, higher mortality rates and higher rates of deep-hooking and bleeding were associated with J-hooks relative to circle hooks. We conclude that empirical evidence is sufficient to promote circle hook use in almost all hook-and-line fishery sectors that typically interact with istiophorids. However, billfish conservation benefits will only be realized if fishers use unmodified circle hooks, commit to releasing live fish and take other appropriate measures which maximize post-release survival. While there may be fishing modes where circle hook effects are negative, for billfish conservation, we recommend managers grant exceptions to circle hook use only when experimental results support such a practice. [source] The relationship between bed rest and sitting orthostatic intolerance in adults residing in chronic care facilitiesJOURNAL OF NURSING AND HEALTHCARE OF CHRONIC ILLNE SS: AN INTERNATIONAL INTERDISCIPLINARY JOURNAL, Issue 3 2010Mary T Fox MSc fox mt, sidani s & brooks d (2010) Journal of Nursing and Healthcare of Chronic Illness2, 187,196 The relationship between bed rest and sitting orthostatic intolerance in adults residing in chronic care facilities Aim., To examine the relationship between orthostatic intolerance and bed rest as it was used by/with 65 adults residing in chronic care facilities. Background., The evidence on the relationship between bed rest and orthostatic intolerance has been obtained from aerospace studies conducted in highly controlled laboratory settings, and is regarded as having high internal validity. In the studies, prolonged and continuous bed rest, administered in a horizontal or negative tilt body position, had a major effect on orthostatic intolerance in young adults. However, the applicability of the findings to the conditions of the real world of practice is questionable. Methods., Participants were recruited over the period of April 2005 to August 2006. A naturalistic cohort design was used. The cohorts represented different doses of bed rest that were naturally occurring. Comparisons were made between patients who had no bed rest (comparative dose group, n = 20), two to four days (moderate dose, n = 23) and five to seven days of bed rest (high dose, n = 22) during a one-week monitoring period. Orthostatic intolerance was measured by orthostatic vital signs and a self-report scale. Bed rest dose was measured by the total number of days spent in bed during one week. Results.,Post hoc comparisons, using Bonferroni adjustments, indicated significant differences in adjusted means on self-reported orthostatic intolerance between the comparative and high (CI: ,4·12, ,0·85; p < 0·001), and the moderate and high (CI: 0·35, 3·56, p < 0·01) bed rest dose cohorts. No group differences were found on orthostatic vital signs. Conclusions., A moderate dose of bed rest with intermittent exposure to upright posture may protect against subjective orthostatic intolerance in patients who are unable to tolerate being out of bed every day. Future research may examine the effects of reducing bed rest days on orthostatic intolerance in individuals with high doses of five to seven days of bed rest. [source] Effect of two medicinal herbs (Astragalus radix and Lonicera japonica) on the growth performance and body composition of juvenile pikeperch [Sander lucioperca (L.)]AQUACULTURE RESEARCH, Issue 11 2008Zdzis, aw Zak Abstract The aim of this study was to determine the impact of feeding juvenile pikeperch diets with medicinal herb adjuvants on the growth performance, proximate body composition, fatty acids profile (whole fish, muscle tissues, viscera) and cytological and histological indicators of the liver and middle intestine. The fish (mean body weight of ca. 110 g) were fed diets with a 0.1% supplement of Astragalus radix (group A), Lonicera japonica (group L) or a mixture of these herbs (A. radix+L. japonica; group A/L) for 8 weeks. The herbal supplementation was not noted to have had an impact on the analysed indicators of fish growth performance, condition or feed conversion ratio (P>0.05). Statistically significant intergroup differences were noted in the value of the hepatosomatic index, hepatocyte size, their nucleus and nucleus/cytoplasm diameter ratio (P<0.05). Significant intergroup differences were also noted in the appearance of the hepatic parenchyma. Statistically significant intergroup differences were also noted in the protein content of the whole fish body. The analysis of the proximal composition of the fish viscera, in turn, indicated significant differences in the fat content (P<0.05). Among the analysed group of fatty acids (saturated , SFA, monoenoic , MUFA, polyenoic , PUFA) contained in the whole fish, the fillets and the viscera, significant intergroup differences were noted with regard to SFA (viscera) and MUFA (whole fish) (P<0.05). The total PUFA content was stable, although significant intergroup differences were noted with regard to a few of the acids that belong to this group (P<0.05). [source] | ||||||||||