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91.
The elevated presence of metal(loid)s in the environment significantly impacts ecosystems and human health and is generally largely due to industrial and mining activities. Thus, in the current study, we investigated and proposed an environmentally friendly method (phytomanagement) aimed at reducing the negative impacts associated with metal(loid) pollution through the use of soil amendments (biochar and compost) to permit Ailanthus altissima growth on a highly contaminated mining Technosol, with arsenic (As) and lead (Pb) contents of 539.06 and 11 453 mg kg-1, respectively. The objective was to examine the impacts of three biochars and compost on i) the physicochemical characteristics of soil, ii) metal(loid) immobilization in soil, and iii) A. altissima growth. We revealed that the application of biochar as a soil amendment improved soil conditions by increasing soil electrical conductivity, pH, and water-holding capacity. Moreover, concomitantly, we observed a large reduction (99%) in Pb mobility and availability following application of the hardwood biochar in combination with compost (HBCP). Thus, this combined soil amendment was most effective in promoting A. altissima growth. In addition, the HBCP treatment prevented As translocation in the upper parts of plants, although soil pore water As concentration was not diminished by amendment application.  相似文献   
92.
1. The influence of the shell membranes on shell strength was studied in 21 Single Comb White Leghorn eggs.

2. Shell deformation and shell thickness were plotted for each egg and the regression line was calculated. The difference between the observed shell deformation and that predicted by the regression line was calculated for each egg and this distance, with changed sign, was called the shell deformation index.

3. The force needed to separate the shell membranes from a 10 mm wide strip of the shell was determined by a tensile testing machine and was termed attachment strength.

4. The correlation between shell deformation index and attachment strength was highly significant (r=0.88, P<0.0005). Thus the shell membranes contribute to shell strength, probably by serving as a reinforcement of the crystalline part of the shell.  相似文献   

93.
Tropical Animal Health and Production - The primary objective of the present study was to assess the effects of vitamin and mineral premix (VMP) withdrawal from the diets 30 and 60&nbsp;days...  相似文献   
94.
Hazelnut (Corylus avellana L.) is mostly grown in rainfed condition in Turkey as well as other some countries in the world without more yield reduction. However, there is not enough information about how to give yield without more reduction in rainfed hazelnut orchard. In an endeavor to search this question, quantifications of leaf water potential (LWP), stomatal conductance (gs) and photosynthetically active radiation (PAR) of hazelnut tree were investigated in rainfed hazelnut orchard in the summer of 2013 and 2014. Additionally, possible effects of those quantifications on rainfed hazelnut trees vs. soil water content (SWC) was investigated. Results of this study exhibited that yearly ET (evapotranspiration) of rainfed hazelnut trees was higher in 2014 than 2013 even though seasonal ET of rainfed hazelnut trees was higher in 2013 than 2014. Hence, yield, LWP and gs were higher in 2014 than 2013 but PAR and SWC (even all the study season) were mostly higher in 2013 than 2014. Moreover, relationships of LWP, gs and PAR and responses of LWP, gs and PAR to SWC were non stronger. These differences could be attributed differences of climate variability such as precipitation and temperature during the observed period throughout the season in the studied years. However, rainfed hazelnut trees may be required supplement irrigation in dry summer, such as year of 2013, to avoid summer water stress. Finally, it can be concluded that hazelnut trees can be grown well and give normal yield for the areas which have about 950 mm precipitation.  相似文献   
95.
96.
Intestinal wall thickness is neither a specific nor sensitive ultrasound parameter for detecting intestinal inflammation. We hypothesize that mucosal echogenicity, lymphadenomegaly, and secondary findings of the gastrointestinal tract would be more sensitive and specific markers for detecting and differentiating causes of chronic inflammatory bowel disease in dogs. Fifty-six client-owned dogs with chronic diarrhea and 10 control dogs were examined with two-dimensional, gray-scale ultrasound (time 0, 4, and 10 weeks post therapy) and small intestinal mucosal biopsies were performed at the 0- and 4-week time points. The clinical activity was assessed at each time point using the canine inflammatory bowel disease activity index (CIBDAI). Fifty-one dogs had inflammatory infiltration of the duodenal mucosa and were divided into three groups, food-responsive disease, idiopathic inflammatory bowel disease, and protein-losing enteropathy, based on their response to the different treatments and histology. Two different patterns of increased echogenicity of the mucosa were detected: hyperechoic speckles and hyperechoic striations. A normal, hypoechoic bowel mucosa in dogs with chronic diarrhea had a sensitivity of 80% and a specificity of 81% for the diagnosis of food-responsive disease. Hyperechoic striations had a sensitivity of 75% and a specificity of 96% for dogs with protein-losing enteropathy. Hyperechoic speckles were non-specific for diagnosing inflammatory bowel disease. There was a significant relationship between ultrasound score and CIBDAI at t0, but not following therapy. Mucosal echogenicity may be a better parameter for detecting inflammatory bowel disease than bowel wall thickness in dogs with chronic diarrhea.  相似文献   
97.

The Anatolian ground squirrel (Spermophilus xanthoprymnus) is a typical example of true mammalian hibernators. In order to adapt to extreme external and internal environments during hibernation, they lower their body temperatures, heart rates and oxygen consumption; however, pathological events such as ischemia and ventricular fibrillation do not occur in their cardiovascular systems. During the hibernation, maintenance of cardiac function is very important for survival of ground squirrels. Natriuretic peptides (NPs) are key factors in the regulation of cardiovascular hemostasis. Since NPs’ role on the protection of heart during hibernation are less clear, the aim of this study was to investigate dynamic changes in NPs content in the cardiac chambers and to reveal the possible role of NPs on establishing cardiac function in ground squirrel during hibernation using immunohistochemistry. The immunohistochemical results indicate that cardiac NP expressions in atrial and ventricular cardiomyocytes were different from each other and were sex-independent. ANP and BNP were expressed in a chamber-dependent manner in female and male squirrel hearts. Furthermore, cardiac NPs expression levels in hibernation period were lower than those at the pre-hibernation period. During prehibernation period, ANP, BNP and CNP were expressed in the white and beige adipocytes of epicardial adipose tissue (EAT); while during hibernation period, the brown adipocytes of EAT were positive for BNP and CNP. These data suggest that the hibernation-dependent reduction in levels of NPs, particularly ANP, in cardiac chambers and EAT may be associated with low heart rate and oxygen consumption during hibernation. However, further studies are needed to better delineate the roles of NPs during the hibernation.

  相似文献   
98.
Pentzia incana is one of the most important of all natural pasture plants in the dry interior (Karoo) region of South Africa. This highly aromatic shrub is thought to be responsible for the distinctive flavour of Karoo lamb (a registered geographical indication), yet the essential oil is here characterised for the first time. Leafy twigs are traditionally chewed for relief of stomach ache. Essential oil is associated with numerous small, multicellu- lar glands. Gas chromatography and gas chromatography/mass spectrometry analysis of 17 essential oil samples from five populations showed considerable variation in both yield (0.12% to 0.88% dry weight) and composition. Of interest was the presence of one major biosynthetic group comprising yomogi alcohol (to 38.9%), artemisia alcohol (to 26.1%), artemisia ketone (to 35.0%) and artemisyl acetate (to 9.4%). High levels of fragranol (26.9%) and fragranyl acetate (27.1%) were observed only in a single specimen. Other main compounds were 1,8-cineole (to 16.7%), santolina alcohol (to 11.3%), camphor (to 47.9%), linalyl acetate (to 17.4%) and bicyclogermacrene (to 11.8%). Six of the 10 major compounds were isolated and their identities confirmed by nuclear magnetic resonance. The volatile compounds may possibly be linked to the medicinal use of P. incana, as well as the flavour profile of Karoo lamb.  相似文献   
99.
In 2009 a greenhouse experiment was conducted to determine the effects of boron (B) and plant growth-promoting rhizobacteria (PGPR) on wheat (Triticum aestivum spp. vulgare cv ‘Bezostiya’) and barley (Hordeum vulgare cv ‘Tokak’) on plant growth, freezing injury, and antioxidant enzyme capacity. Results showed that boron (0, 1, 3, 6, 9 kg B ha?1) and PGPR application (Bacillus megaterium M3, Bacillus subtilis OSU142, Azospirillum brasilense Sp245 and Raoultella terrigena) at which 50% of leaves were injured (LT50) values and ice nucleation activities in both plants were found statistically significant. Boron application with all PGPR strains decreased LT50 values in wheat and barley plants under noncold stress (NCS) and cold stress conditions (CS). There were statistically significant differences between bacterial inoculation and B fertilizer in terms of root and shoot dry weight under NCS and CS conditions. Reactive oxidative oxygen species (ROS) and antioxidant enzyme activities (SOD, POD, CAT) were negatively affected CS conditions and decreased with reduced temperatures of media, but B and PGPR applications alleviated the low-temperature deleterious effects in both plants species tested. The lowest ROS and antioxidant enzyme (SOD, POD, CAT) of wheat and barley were observed with 6 kg B ha?1 with R. terrigena.  相似文献   
100.
Applying by-products as soil amendments to agricultural systems is growing in popularity. We aimed to assess the efficacy of some contemporary by-products to provide nutrients to crops as well as the potential harm of adding toxic elements to the environment. Four different by-products widely available in Northern Europe were tested for their effects on two nutrient-poor agricultural soils in terms of increasing available macro- and micro-nutrients as well as toxic elements. Assessing soil microbial community as a sensitive tool for evaluating soil quality was conducted with the focus on microbial activity, carbon metabolism and on Rhizobium/Agrobacterium. Wood ash increased pH and CaEDTA, KEDTA and MgEDTA in the soils. The only increase in EDTA-extractable micronutrients in the soils was observed by applying pot ale, increasing Cu. None of the amendments increased the availability of Pb and Cd in the soils. Soils amended with the by-products thus remained similar to the unamended control but were quite different from fully mineral fertilised soils. There were no detectable adverse effects on the physiological and genetic profiles of microbial communities. The by-products were moderately beneficial and did not change the soil microbial community as much as the fully fertilised treatment with mineral fertilisers. Changes in the microbial community profiles were probably due to direct effects on microbes limited by K, Ca and N as opposed to indirect effects on plant growth. This is potentially significant in understanding how to improve impoverished and marginal soils as microbial activity affects many other ecosystem functions.  相似文献   
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