汉江流域不同土地利用方式下土壤反硝化率及其控制因素研究

Land-use patterns can affect various nutrient cycles in stream ecosystems, but little information is available about the effects of urban development on denitrification processes at the watershed scale. In the presented study, we investigated the controlling factors of denitrification rates within the streams of the Han River Basin, Korea, with different land-use patterns, in order to enhance the effectiveness of water resource management strategies. Ten watersheds were classified into three land-use patterns （forest, agriculture and urban） using satellite images and geographic information system techniques, and in-situ denitrification rates were determined using an acetylene blocking method. Additionally, sediment samples were collected from each stream to analyze denitrifier communities and abundance using molecular approaches. In-situ denitrification rates were found to be in the order of agricultural streams （289.6 mg N20-N m-2 d-1） 〉 urban streams （157.0 mg N20-N m-2 d-1） 〉 forested streams （41.9 mg N20-N m-2 d-l）. In contrast, the average quantity of denitrifying genes was the lowest in the urban streams. Genetic diversity of denitrifying genes was not affected by watershed land-use pattern, but exhibited stream-dependent pattern. More significance factors were involved in denitrification in the sites with higher denitrification rates. Multiple linear regression analysis revealed that clay, dissolved organic carbon and water contents were the main factors controlling denitrification rate in the agricultural streams, while dissolved organic carbon was the main controlling factor in the urban streams. In contrast, temperature appeared to be the main controlling factor in the forested streams.     

Effect of Ethylene Treatment on Kiwifruit Bioactivity

The consumption of fruits and vegetables with high antioxidant activities leads to best healthful results. Therefore, in the present investigation we tried to find the peak of the kiwifruits antioxidant activity during the first 10 days of ethylene treatment (100 ppm at 20 °C).In order to receive the most reliable data five different antioxidant assays were used: ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC); trolox equivalent antioxidant capacity (TEAC); 1, 1-diphenyl-2-picrylhydrazyl radical (DPPH); and Folin-Ciocalteau. It was found by all applied methods that kiwifruit samples have the highest contents of polyphenols and flavonoids and the highest antioxidant activity on the 6-th day of the ethylene treatment. The correlation coefficients between polyphenols, flavonoids and antioxidant activities of kiwifruit methanol extracts with TEAC and CUPRAC, were as followed: 0.81 and 0.63, and 0.23 and 0.17, respectively, and showed that the free polyphenols correlation coefficients were higher than that of the flavonoids.In conclusion: during ethylene treatment the bioactivity of kiwifruit is increasing and reaches its maximum at the 6th day and therefore it is the optimum time for kiwifruit consumption; total polyphenols were the main contributor to the overall antioxidant activity of kiwifruit; the most sensitive test for antioxidant activities determination is FRAP.     

参菩灌洗液治疗儿童腺样体肥大的临床观察

〔摘要〕目的观察参菩灌洗液鼻咽腔灌洗治疗儿童腺样体肥大伴慢性鼻窦炎的疗效〔方法采用参菩灌洗液 鼻咽腔灌洗治疗儿童腺样体肥大伴慢性鼻窦炎52例为治疗组,设对照组西药治疗51例,对比观察其临床疗效、结 果治疗组总有效率为94.20Io,对照组为78.10Ic,差异有统计学意义(P<0.05 )〔结论参菩灌洗液局部灌洗有明显促 进腺样体缩小和治疗鼻窦炎的作用、     

连翘提取物对肉仔鸡热应激下生长性能和抗氧化活性的影响

选用1日龄健康的爱拔益加肉公雏196只,平均体重为(38.8±1.3)g,研究连翘提取物(FSE)对热应激(32±1)℃环境下肉鸡生长性能和抗氧化能力的影响。将肉仔鸡随机分为3个处理,每个处理14个重复,每个重复6只鸡。日粮处理组,分别为空白对照组(NC),维生素C组(PC):基础日粮+维生素C200mg/kg;连翘提取物组(FSE):基础日粮+FSE100mg/kg。结果表明:试验前期各处理间生长性能没有显著性差异。试验后期FSE组与NC组相比日增重显著提高(P<0.05),并且饲料转化率提高。FSE组比NC组血液总抗氧化能力(TAOC)、超氧化物歧化酶(SOD)含量显著提高(P<0.05),而丙二醛(MDA)水平下降。从试验全期看FSE组比NC组肝脏SOD含量显著提高(P<0.05)。说明FSE通过清除自由基途径,缓解活性氧对肠黏膜的损伤,改善营养物质消化率和生长性能,FSE有望成为高效天然抗氧化剂。     

Effects of drought stress on root morphology and spatial distribution of soybean and adzuki bean

Due to global climate change, Korea is facing severe droughts that affect the planting and early vegetative periods of upland crops. Soybean and adzuki bean are important legume crops in Korea, so it is critical to understand their adaptations to water stress. This study investigated the changes in root morphological properties in soybean and adzuki bean and quantified the findings using fractal analysis. The experiment was performed at the National Institute of Crop Science in Miryang, Korea. Soybeans and adzuki beans were planted in test boxes and grown for 30 days. The boxes were filled with bed soil with various soil moisture treatments. Root images were obtained and scanned every two days, and the root properties were characterized by root length, depth and surface area, number of roots, and fractal parameters(fractal dimension and lacunarity). Root depth, length and surface area and the number of roots increased in both crops as the soil moisture content increased. The fractal dimension and lacunarity values increased as the soil moisture content increased. These results indicated that the greater the soil moisture, the more heterogeneous the root structure. Correlation analysis of the morphological properties and fractal parameters indicated that soybean and adzuki bean had different root structure developments. Both soybean and adzuki bean were sensitive to the amount of soil moisture in the early vegetative stage. Soybean required a soil moisture content greater than 70% of the field capacity to develop a full root structure, while adzuki bean required 100% of the field capacity. These results would be useful in understanding the responses of soybean and adzuki bean to water stress and managing irrigation during cultivation.     

Effect of probiotics on growth performance,development of small intestinal tract and microbial populations in broilers

The experiment was conducted using a total of 1392 one-day-old, Cobb commercial male broilers to investigate the effects of a commercial probiotic addition in diet on growth, the development of the small intestine and microbial populations of broilers. Broilers were randomly allotted by BW to 1 of 6 replicate cages （29 chicks per cage） for each of 8 treatments in a randomized block design involving one factorial arrangement of treatments. Dietary treatments included the basal diet （including corn, soybean, rapeseed, cottonseed meal） added with 100 mg/kg antibiotic, 0%, 0.05%, 0.1%, 0.15%, 0.2%, 0.25% or 0.3%. The experiment last 42 d and divided into the starter period （1-21 d） and the finisher period （22-42 d）. The results showed that there were significant differences in broiler body weight （BW） （P〈0.001）, average daily feed intake （ADFI） （P=0.033）, relative length of the duodenum （P〈0.001）, jejunum （P=0.008）, ileum （P〈0.001） and the populations of lactobacillus （P〈0.001） and coliform （P〈0.001） in the rectum between the probiotics treatments and the control treatment only in the starter period of the trails. No significant differences were observed in intestinal morphology parameters in two periods of the experiment. Our results indicated that the probiotic was able to improve the performance of broiler chickens, and it was better in the starter period to be used than in the finisher period.     

Improvement of bacterial clearance and relief of clinical signs of Salmonella enterica serovar Typhimurium infection in pigs through upregulation of Th 1-specific responses by administration of a combination of two silicate minerals,biotite and bentonite

Biotite and bentonite are phyllosilicate minerals that were originally used inindustrial applications. Several beneficial activities of them have recently beenreported, especially regulation of the immune system and antimicrobial effects. Therefore,we investigated the immune-enhancing and bacterial clearance effects of a biotite andbentonite mixture (BBM) on experimental infection of Salmonella entericaserovar Typhimurium (S. Typhimurium) to determine whether the BBM couldbe used as an alternative antibiotic. We administered 1% or 2% BBM as a feed supplement.We then evaluated the bacterial clearance effects of the BBM against S.Typhimurium. We also evaluated the immune-enhancing effect of the BBM through severalimmunological experiments that included examination of the lysozyme activity,CD4⁺/CD8⁺ T lymphocyte ratio and the T-helper type 1 (Th 1)cytokine profile. The clinical signs of S. Typhimurium and the number ofviable bacteria in feces and tissues were significantly decreased in both BBM groups,especially in the 2% BBM group. The BBM also markedly enhanced the lysozyme activity,CD4⁺/CD8⁺ T lymphocyte ratio and expression levels of IFN-γ andIL-12 in S. Typhimurium-challenged pigs. Therefore, the BBM could be agood candidate as an alternative antibiotic that improves Th 1-specific immune responsesand the bacterial clearance effect.     

Effects of bamboo charcoal and bamboo vinegar as antibiotic alternatives on growth performance,immune responses and fecal microflora population in fattening pigs

This study was carried out to investigate the effects of bamboo charcoal and bamboo vinegar as alternatives of antibiotics in the diet of fattening pigs and their influence on growth performance, immune responses and fecal microflora populations. Crossed pigs (n = 144, 79 kg body weight) were divided into 12 heads per pen, four diets and three replications. The basal diet (negative control: NC) was supplemented with 0.3% antibiotics (positive control: PC), 0.3% bamboo charcoal (BC) and 0.3% bamboo vinegar (BV). Average daily weight gain and feed efficiency were higher (P < 0.05) in PC, BC and BV. The concentration of lactate dehydrogenase and cortisol were lower (P < 0.05), but the concentration of immunoglobulin G (IgG) and IgA were higher (P < 0.05) in PC, BC and BV. Counts of coliform bacteria and Salmonella spp. were lower (P < 0.05), while the counts of fecal anaerobic total bacteria and lactic acid bacteria were higher (P < 0.05) in PC, BC and BV. A reasonable inclusion of bamboo charcoal or bamboo vinegar as antibiotics in the diet of fattening pigs leads to a better growth performance, immune responses and fecal microflora populations. The results of the present study suggest that bamboo charcoal or bamboo vinegar could be a potential additives in animal production as an alternative to antibiotics.     

COMPUTED TOMOGRAPHY ANGIOGRAPHY FOR EVALUATION OF PULMONARY EMBOLISM IN AN EXPERIMENTAL MODEL AND HEARTWORM INFESTED DOGS

This study was performed to characterize pulmonary embolism with computed tomography pulmonary angiography in experimental pulmonary embolism and heartworm infected dogs. In the experimental group, there were pulmonary changes after pulmonary embolism induction as follows: hypoattenuating round filling defects in pulmonary arteries, arterial dilations with straight and abrupt cut‐off appearances in the pulmonary embolism regions, pulmonary infarctions, a cavity formation and spontaneous pneumothorax, and emboli migration. In the heartworm‐infected group, three out of eight dogs developed pulmonary embolism, especially in the right caudal arteries. Arterial dilations with typical tortuosity were also identified, mainly in the right caudal arteries in five dogs. Computed tomography pulmonary angiography can be an important imaging modality in the diagnosis of pulmonary embolism and the evaluation of pulmonary arterial and parenchymal changes in dogs.     

Exploratory Celiotomy in 200 Nontraumatized Dogs and Cats

Two hundred dogs and cats undergoing exploratory celiotomy for reasons other than trauma were grouped by disease classification and by body system affected. There were 61 animals in which infection or inflammation predominated, 63 animals with neoplasia, and 76 animals with noninflammatory and non-neoplastic conditions. Body systems affected were digestive, lymphatic, urinary, reproductive, other, and undetermined. Seventy-three percent of the animals survived the hospitalization period; survival rates for animals with infection or inflammation, neoplasia, and other disorders were 69%, 60%, and 86%, respectively. Within the same groups, the exploratory celiotomy provided strictly diagnostic information in 72%, 79%, and 24% of the animals, and surgical treatment was provided to 28%, 21%, and 58% of the animals, respectively. Intraoperative cytologic and histologic diagnoses were consistent in 78% of the animals; the consistency rates for animals with infection or inflammation, neoplasia, and other disorders were 81%, 88%, and 59%, respectively. Complications after surgery were observed in 30% of the animals, with 60% of the complications disease related. Complications were observed in six animals with reproductive disorders (67%), six animals with urinary disease (46%), 35 animals with digestive disease (29%), and three animals with lymphatic disease (13%).