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91.
Water, Air, & Soil Pollution - Microbial fuel cells (MFCs) have gained increasing attention as an effective pathway for wastewater treatment and electrical energy recovery. In this study, the...  相似文献   
92.
选取7个密度等级的规格竹条,将相同密度等级的规格竹条组坯制备竹层板,并分别对其物理力学性能进行评价。结果表明:竹层板的密度与相应的规格竹条密度具有一致性;竹层板的顺纹抗拉弹性模量与强度、顺纹抗压强度、抗弯弹性模量与强度等均值随其密度的增大呈现增大的趋势;而三点弯冲击韧性随密度的增加呈现先增加后减小的趋势,且不同密度竹层板力学性能指标有交叉,相同密度等级的竹层板力学性能指标变异性较大。规格竹条密度分级能够有效控制竹层板的密度,仅在一定程度上优化竹层板的力学性能。  相似文献   
93.
The feed additive was composed of six Chinese Herbal (CH) (including Poria, Astragalus, Cork, Orange peel, Hawthorn and Radix), which were fermented by Lactobacillus and used as a feed additive for piglets basal diet. Similar to group of antibiotic and herbal medicine, fermented herbal medicine was additived to basic diet in four trials with eight replications per trial, determining effect on the growth performance, biochemical and immunological indicators. Compared with the control group, the group of fermented herbal compound had higher Average Daily Gain (ADG), higher content of immune globulin M (IgM) and immune globulin A (IgA) (p<0.05). There was no significant effect on the indicators of ADG, Average Daily Feed Intake (ADFI) and diarrhea rate (p>0.05) between groups of antibiotic and fermented herbal were observed; however, the concentrations of Total Protein (TP), Growth Hormone (GH), IgG, IgM and IgA significantly increased (p<0.05) compared with the control group.  相似文献   
94.
为了解不同干燥方式对白萝卜干制品品质和微观结构的影响及变化情况,以新鲜白萝卜为原料,采用振动远红外干燥方式和传统远红外干燥方式对白萝卜进行干燥,研究其对营养成分、复水比、干燥时间、脱水速率、感官品质以及微观结构的影响。结果表明:振动远红外干燥方式干制的白萝卜样品中蛋白质、维生素C、芥子油苷、总糖、脂肪和复水比明显高于传统远红外干燥方式制得的样品;相比于传统远红外干燥方式,干燥时间缩短了0.67 h,脱水速率提高了40.58%;干制品感官品质和微观结构均优于传统远红外干燥方式。研究为远红外干燥方式在白萝卜方面的应用提供理论依据与技术参考。  相似文献   
95.
The effects of flavonoids on methanogenesis and microbial flora in Dorper × thin‐tailed Han crossbred ewes were evaluated in two experiments. To investigate the effects of flavonoids on nutrient digestibility and nitrogen balance, 18 ewes (60.0 ± 1.73 kg body weight (BW)) were allotted to two dietary treatments in experiment one, a control diet and the control diet supplemented with flavonoids (2 g/head/day). In experiment two, the effects of supplementary flavonoids on ruminal fermentation and microbial flora were investigated using quantitative polymerase chain reaction with six ewes (67.2 ± 0.79 kg BW) with ruminal cannula assigned to the identical dietary treatments used in experiment one. Supplementary flavonoids improved the apparent digestibility of nitrogen (N, P < 0.001) and neutral detergent fibre (NDF, P = 0.024) and decreased daily CH4 output (P < 0.001). The ruminal pH (P = 0.638) and ammonia (P = 0.690) were not affected by supplementary flavonoids, whereas the total volatile fatty acid (VFA) content increased (P = 0.037). Supplementary flavonoids decreased ruminal populations of protozoans (P = 0.002) and methanogens (P < 0.001) and increased the populations of Fibrobacter succinogenes (P = 0.016). In conclusion, flavonoids improved the digestibility of organic matter and reduced CH4 output by inhibiting the populations of microbes involved in methanogenesis.  相似文献   
96.
The objective of this study was to assess the effect of dietary probiotics on rumen fermentation and the bacterial community in dairy calves. Twelve Holstein calves were randomly allocated to three treatments: a basal diet, the basal diet supplemented with Lactobacillus plantarum GF103 (LB) or basal diet supplemented with a mixture of Lactobacillus plantarum GF103 and Bacillus subtilis B27 (LBS). A milk replacer was fed to calves from 8 days of age. A starter and alfalfa hay was offered ad libitum from 21 and 28 days of age, respectively, and the orts were weighted daily. The ruminal fluid was sampled at 56 and 83 days of age to determine the rumen fermentation characteristics. The bacterial community was analyzed by denaturing gradient gel electrophoresis (DGGE) and the number of certain bacteria was quantified by real‐time polymerase chain reaction. The ratio of total dry matter intake to average body wieght was higher in the control (P < 0.05). The DGGE fingerprint of the 16S ribosomal RNA gene was affected by the blended probiotics at 83 days of age. The number of Ruminococcus albus was lower in the LB and LBS treatment (P < 0.05). Oral administration of the probiotics affected the rumen bacterial community and the numbers of cellulolytic bacteria decreased.  相似文献   
97.

Objective

To evaluate the behavior and some cardiopulmonary variables of dexmedetomidine–midazolam or dexmedetomidine–midazolam-butor-phanol in the silver fox (Vulpes vulpes).

Study design

Blinded, randomized design.

Animals

Sixteen adult silver foxes, aged 7–9 months, weighting 6.0–9.2 kg.

Methods

Animals were randomly assigned to dexmedetomidine (50 μg kg?1) and midazolam (0.45 mg kg?1) (group DM) or to dexmedetomidine (30 μg kg?1), midazolam (0.45 mg kg?1) and butorphanol (0.25 mg kg?1) (group DMB), administered intramuscularly. Pulse rate (PR), respiratory rate (fR), noninvasive arterial pressures, oxygen saturation (SpO2), rectal temperature (T) and behavioral scores (posture, sedation, antinociception, jaw relaxation and auditory response) were measured at 5, 10, 20, 30, 40, 50 and 60 minutes after injection. Time from drug injection to recumbency with no response to stimuli (IT) and time from administration of atipamezole (0.2 mg kg?1) to standing with coordination (RT) were recorded. The occurrences of adverse events were recorded. Data were analyzed by two-tailed unpaired t-tests and Bonferroni post hoc tests. Significant differences were accepted at p<0.05.

Results

There were no statistically significant differences between the groups for IT or RT. Arterial pressures were higher in DMB at each time point except at 5 minutes. PR was lower in DM at each time point except at 10 and 60 minutes. No significant difference was found between the groups for fR, SpO2 and T. The behavioral scores were significantly lower (lower quality immobilization) in DMB at 5,10 and 60 minutes.

Conclusions and clinical relevance

IT and RT were not different between the groups. Both protocols provided immobilization for 30–40 minutes with excellent muscle relaxation and analgesia adequate for clinical examinations and some simple surgical procedures.  相似文献   
98.
Eighteen Chinese Holstein heifers average age 230 ± 14 days were allocated to 1 of 3 dietary crude protein (CP) to metabolizable energy (ME) ratios to examine the effects on growth performance, blood metabolites and rumen fermentation parameters with 90‐days experiment. Three different dietary CP:ME ratios were targeted based on the formulation of dietary CP contents of 10.85%, 12.78% and 14.63% on dry matter (DM) basis with similar ME contents (10.42 MJ/kg DM), which were categorized as low, medium and high dietary CP:ME ratios. The actual CP:ME ratios obtained in this study significantly increased from low to high CP:ME ratio groups with a value of 10.59, 11.83 and 13.38 g/MJ respectively. Elevated CP:ME ratios significantly increased CP intake (kg/day) and feed efficiency (FE) which was defined as dry matter intake as a proportion of average daily gain (ADG), whereas little difference was observed in body weight (kg), ADG (kg/day), DM intake (kg/day) and ME intake (MJ/day) among the three different CP:ME ratio groups. Increasing dietary CP to ME ratios significantly increased CP digestibility, whereas digestibility of DM and gross energy remained constant in the current experiment. Blood urea nitrogen and insulin‐like growth factor‐1 linearly increased with increasing dietary CP:ME ratios. There was significantly dietary treatment effect on rumen fermentation parameters including acetate, propionate, butyrate and total volatile fatty acids. Therefore, this study indicated that increasing dietary CP levels with similar energy content contributed to increased protein intake and its digestibility, as well as FE. Holstein heifers between 200 and 341 kg subjected to 13.38 dietary CP:ME ratio showed improved feed efficiency, nutrient digestibility, some blood metabolites and rumen fermentation characteristics for 0.90 kg/day rate of gain.  相似文献   
99.
DNA methylation, an epigenetic mechanism used by cells to control gene expression, has an important biological role in plant development and environmental fitness. Since plant DNA methylation is closely related to environmental conditions, variation during the day is expected. Here, in genetically identical plants of Populus nigra clone N46, DNA methylation changes in leaves over a 24 h period were detected using the methylation-sensitive amplification polymorphism method. The results showed different DNA methylation patterns in mature poplar leaves: not only in individuals at the same time, but also in samples at each of the six time during the day. In addition, night samples had a higher percentage of methylation than in morning samples. However, no statistically significant differences were found among the samples gathered at different times. Similar results were obtained for three other P. nigra clones with different genetic backgrounds. Real time qPCR showed that the DNA methyltransferase genes Pt-MET1 and Pt-SOM1 involved in CG DNA methylation in poplar were stable over a 24 h period in leaves of P. nigra N46 compared with circadian-controlled genes. That could be part of the reason that methylation of CCGG sites is stable in those leaves. That DNA methylation differed even in genetically identical plants indicates the specificity of DNA methylation changes in their genomes. No statistically significant differences in methylation changes were found between day and night, suggesting that DNA methylation is more stable than expected and is unlikely to be involved in circadian regulation in plants.  相似文献   
100.
亚洲百合杂交亲和性研究   总被引:2,自引:0,他引:2  
本实验用常规授粉的方法,对亚洲百合自交、系内杂交和系间杂交亲和性进行了研究,旨在为百合育种研究提供一定的依据。通过试验发现,自交试验中只有‘Mount Duckling’得到膨大的果实;系内杂交试验中共计19个杂交组合,其中13个组合得到膨大的果实,10个组合得到胚;系间杂交试验中以2个东方百合品种为父本,共计12个杂交组合,均未得到胚。通过研究还发现,正反交对结实率也有很大影响。  相似文献   
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