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81.
The effect of hydroxypropyl-β-cyclodextrin (HPβCD) in the dyeing of polyamide fabric was investigated under conditions that mimic industrial dyebaths where dye mixtures are used. The dyes used were Telon Red BN, Telon Yellow A-2R, and Telon Blue RR. The blue dye complexed with HPβCD whereas the other dyes did not do so under the conditions used. The dyeing results were compared with those obtained using a traditional retarding agent, Albegal B. The exhaustion dyeing data showed that HPβCD mainly affected the dyeing behavior of the blue dye that became encapsulated. In the case of the yellow and red dyes, changes in the overall kinetics of dyeing were observed, resulting in modified exhaustion profiles. In comparison, Albegal B retarded the blue dyeing process and increased the rate of exhaustion of the yellow dye while the exhaustion curve of red dye remained unchanged. The color uniformity of the dyed polyamide was improved when HPβCD was used. This resulted from the more controlled exhaustion rate during the critical phase of the dyeing process.  相似文献   
82.
Plant Foods for Human Nutrition - There is great interest in the search for new alternatives to antimicrobial drugs, and the use of prebiotics and probiotics is a promising approach to this...  相似文献   
83.
Irrigation with treated wastewater (TWW) is gaining importance due to declining water availability in dry regions. TWW irrigation has various potential adverse effects on soil quality such as hydrophobic effects on soil surfaces, reducing initial sorptivity and promoting the formation of preferential flow paths. In May and June 2010, in situ infiltration measurements using mini disk tension infiltrometer were deployed in five different orchard plots in Israel to assess the impact of different irrigation water qualities on the soil water repellency index R. In most plantations, long-term test sites were accessed to compare adjacent plots irrigated with fresh water (FW) or TWW. Topsoil samples were analyzed for selected physical and chemical characteristics. The mean R values increased at all TWW sites, from +15 up to +55 % compared with FW sites. The water drop penetration time (WDPT) increased up to 30 fold at three of five TWW sites compared with FW sites. Subsequent U tests and multilevel analysis indicated an impact of the type of irrigation water on R and WDPT. Moreover, soil electrical conductivity and exchangeable sodium percentage were consistently higher at all TWW sites. These results show that irrigation water quality clearly influences physical and chemical properties of the soil.  相似文献   
84.
Drip irrigation systems are prone to changes in flow rate (FR) and increasing coefficients of variation (CV) when fed with treated wastewater, due to fouling inside the drippers. A model system was designed to measure the FR and fouling accumulation in laterals and drippers under different treatment conditions. A novel approach was taken to compare the different maintenance treatments. A comparison of chlorination and acidification strategies showed that daily chlorination and periodic acidification may prolong proper functioning of the drippers by maintaining a normal FR [(up to ±7 %) of nominal FR] and CV (<7 %) index in correlation with low fouling accumulation in the pipeline (<0.01 mg deposit/cm pipe 2 ). Current recommendations for the frequency of conventional treatments were found to be insufficient. Chemical analyses of the fouling inside the dripper and accumulated on the pipe wall showed that biofilm can survive inside the dripper under harsh environmental conditions, even when the pipeline stays clean. These results shed light on biofilm growth and survival mechanisms inside the dripper and may pave the way to developing new treatments or improving dripper design.  相似文献   
85.
Abstract.— The aquaculture performance of mutton snapper Lutjanus analis raised in floating net cages was assessed by measuring their growth, survival, and feed conversion rates during a growout trial conducted in a 3.2‐ha saltwater lake in the Florida Keys, Florida, USA. Approximately 10,500 hatchery‐reared finger‐lings were stocked in two circular, high‐density polyethylene (HDPE) net cages of 7‐m diameter × 7‐m deep (300 m2) and 10‐m diameter × 7‐m deep (600 m3) dimensions. Cages were stocked at 25 fish/m3 (3.2 kg/m3) and 5 fish/m3 (0.72 kg/m3), respectively. Fish grew from a mean of 16.5 g to 302.8 g (25.6 cm TL) in 246 days in the former cage and from a mean of 42.3 g to 245.6 g (23.8 cm TL) in 178 d in the latter cage. Growth rates in weight were best expressed by the following exponential equations: cage 1 (high stocking density): W = 20.716 e0.0112x (r2= 0.83); cage 2 (low stocking density): W = 38.848 e0.0118x (r2= 0.81). Length‐weight data indicate that hatcheryraised, cage‐cultured mutton snapper are heavier per unit length than their wild counterparts. There was no significant difference (P < 0.05) between the slopes of the two lines, indicating that fish in the two cages grew at the same rate. The length‐weight relationships for mutton snapper stocked in cages 1 and 2 are expressed, respectively, by the equations W = 0.000009 L 3.11 (r2= 0.99) and W = 0.000005 L 3.22 (r2= 0.97). Overall feed conversion rate for both cages combined was 1.4. Approximately 10% of the fish sampled exhibited some degree of deformity, particularly scoliosis. Overall survival rate was 70%. Results suggest that L. analis has potential for aquaculture development in net cage systems.  相似文献   
86.
Abstract –  The fish assemblage of the floodplain of the Mamoré River (Bolivia) was estimated in eight lakes, corresponding to four habitat types, situated on an environmental gradient related to the river distance: lakes situated near the river, in the forested floodplain, at the floodplain edge and lakes isolated in the savanna. This paper documents the diet of 71 fish species (among the 140 recorded) and compares the taxonomic and trophic structure of fish assemblages between four lake types. The diet analysis was conducted to determine five trophic guilds: algivores/iliophages, herbivores, zooplanktivores, invertivores and piscivores. The taxonomic and trophic structures of the fish assemblages were not similar in the different lake types of the Mamoré River. The trophic structure of assemblages showed a coarse pattern of dominance of algivores/iliophages and invertivores, but different situations were observed in relative abundance of the trophic groups in relation to the spatial position of the lakes (except for piscivores). Lakes close to the river appeared more favourable to the microphages (algivores/iliophages, zooplanktivores) although remote lakes appeared more favourable to the macrophages (invertivores, herbivores). These results support the general idea that fish distribution follows a pattern linked to the ecology of the species, and related to environmental characteristics of the lakes.  相似文献   
87.
OBJECTIVE: To assess the efficacy of prophylactic hoof health examination and trimming during midlactation at reducing the incidence of lameness during late lactation in dairy cows. DESIGN: Randomized field trial. ANIMALS: 333 Holstein cows. PROCEDURES: Cows without apparent lameness were randomly allocated into 1 of 2 groups approximately 204 days after calving. Cows allocated to the treatment group (n = 161) were examined on a tilt table for diagnosis and underwent hoof-trimming procedures, if needed, for treatment of hoof disorders or lesions. Cows in the control group (n = 172) were not examined. Cows were assigned a locomotion score weekly for 28 weeks after allocation to a group. The number of cows classified as lame during late lactation (approx 205 to 400 days after calving) was compared between groups to assess the efficacy of prophylactic examination and trimming. RESULTS: Incidence of lameness during late lactation was 24% in cows in the control group and 18% in cows in the treatment group. CONCLUSIONS AND CLINICAL RELEVANCE: The 25% decrease in number of new cases of lameness in cows undergoing prophylactic hoof health examination and trimming during midlactation may be relevant for the well-being of dairy cows and should not represent a major economic burden to producers.  相似文献   
88.
Erythrocytes of bovines and other ruminants have a strikingly anomalous phospholipid composition, with low or absent phosphatidylcholine (PC) together with high sphingomyelin (SM) content. Here, we report the presence in normal bovine serum of high levels of anti-phospholipid antibodies of IgM isotype against, PC and the phosphono analogue of phosphatidylethanolamine, aminoethylphosphonolipid (AEPL), normally produced by rumen ciliates. In contrast, no antibodies were detected against SM or N-acyl-phosphatidylethanolamine (NAPE), the major components of bovine erythrocytes. In addition, we found that exposure of the ciliate Tetrahymena thermophila to bovine serum results in rapid lysis, an effect that was inhibited by adsorption of the serum with SM/AEPL liposomes. Furthermore, incubation with bovine serum had a similar effect on freshly obtained ruminal ciliates, and the lytic activity was eliminated by pre-adsorption of the serum with SM/PE liposomes. The ruminant mode of life with its concomitant ciliate fauna is hereby linked to the peculiar conformation of bovine erythrocyte membranes. We propose that the unique phospholipid composition of bovine erythrocytes appears as an evolutionary adaptation to tolerate the lytic effects of anti-phospholipid antibodies generated against AEPL, a membrane component of the huge mass of ruminal ciliates, necessary commensals of this group of mammals.  相似文献   
89.
An “edaphic‐landscape” restoration was performed in two anthracite coal mine spoil heaps located in NW Spain as a demonstration and pilot program for the restoration of coal mine spoils. Terrestrial arthropods were used to monitor the process as an alternative to the use of secondary succession of plants or physico‐chemical indicators of soils. This study analyzes the usefulness of the terrestrial arthropods at different taxonomic levels (orders of Arthropoda, families of Coleoptera, and species of Carabidae) as restoration indicators in the initial restoration stages. The terrestrial arthropods respond rapidly to restoration, and the results may be explained by short‐term increase in abiotic factors resulting from the applied techniques, mainly the animal origin of the organic matter added and the biodegradable coconut geotextile. Carabidae is of relatively low value as a short‐term restoration indicator at a specific level. Coleoptera provided the best information for interpreting the ecological results over the short term and had the best relationship with the cost of identification. Likewise, the results showed that the edaphic‐landscape restoration leads to an abnormal arthropod assemblage in the short term because of an excessive abundance of isopods and polydesmids. No clear convergence appeared toward any of the terrestrial arthropod communities present in the grassland, scrubland, or woodland semi‐natural areas, which were used as reference end point. The restoration indicator value produced by the higher taxonomic levels of the studied terrestrial arthropods may be useful and cost‐effective for assessing short‐term changes caused by environmental restorations performed to recover ecosystems affected by mining activities. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
90.
Summary The weighted least squares (WLS) procedure has been widely used in the analysis of generation means in biometrical genetics. Two methods to carry out the analysis have been presented in the literature (Mather & Jinks, 1971; Rowe & Alexander, 1980). Neither method identified the factors that need to be taken into account when deciding which procedure to use. This paper examines the fitting of the additive-dominance model using the general principles of least squares analysis and presents the statistical basis of each procedure. Mather & Jink's method, which is more realistic according to genetic theory, is based on the assumption that the populations have nonhomogeneous variances. Rowe & Alexander's method is based on the assumption that the populations have homogeneous variances. In the latter case, there is actually no need to do a WLS analysis. The ordinary least square analysis using the original observations rather than the means, will produce the regression parameter estimates.  相似文献   
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