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991.
Nitrogen excreted by aquatic animals mainly takes the form of metabolic wastes such as feces and ammonia, which is accumulated in the intensive aquaculture system and causes serious environmental contamination. So it is very important to determine the waste excretion characteristics of aquatic animals for the development of practical and nonpolluting land‐based aquaculture. Abalone has a unique feeding habit and feeding regime, different from those of finfish; abalone gnaw feed seaweed to produce feces and ammonia continuously. In this study, the rates of feces production and ammonia excretion of pacific abalone, Haliotis discus hannai, of three shell lengths (3, 5, and 7 cm) were investigated under three different temperature conditions (12, 16, and 20 C). All experiments were performed in triplicate in a semirecirculating aquaculture system. Feces were collected for 5 d, and ammonia concentrations (total ammonia nitrogen [TAN]) in the tank inlet and outlet were monitored every 4‐h interval for 24 h at the fourth day of the feces collection. The regressions for the weight‐specific feces production rate (g feces/kg abalone/d) and the weight‐specific TAN excretion rate (mg TAN/kg abalone/d) in relation to water temperature (T, C) and shell length (L, cm) were weight‐specific feces production rate = exp(1.575 ? 281.2/T2 – 0.142L), r2 = 0.9550, and weight‐specific TAN excretion rate = exp(5.052 ? 277.1/T2 ? 0.136L), r2 = 0.9598. Pacific abalone produced 108.3–111.7 g feces and excreted 3.83 g TAN/kg seaweed ingested (dry weight).  相似文献   
992.
Juvenile sablefish, Anoplopoma fimbria (mean length 15.5 ± 1.9 cm, mean weight 68.5 ± 4.8 g), were used to evaluate the effects on growth, oxidative stress, and non-specific immune responses by changes of water temperature (8, 10, 12, 14, 16, 18, and 20 °C) and salinity (100 (35.0), 90 (31.5), 80 (28.0), 70 (24.5), 60 (21.0), 50 (17.5), and 40% (14.0) (‰)) for 4 months. The growth performance was significantly increased at the temperature of 12 and 14 °C, and the feed efficiency was notably decreased at the temperature of 18 °C. The growth performance and feed efficiency were also significantly decreased at low salinity. The antioxidant responses such as superoxide dismutase and catalase were significantly increased by the high temperature and decreased by the low salinity. The immune responses such as lysozyme and phagocytosis were elevated by the temperature of 18 °C and decreased by the salinity of 50%. The results of this study indicate that the growth performance of juvenile sablefish, A. fimbria, is influenced by the temperature and salinity, and the excessive temperature and salinity levels can affect the antioxidant and immune responses.  相似文献   
993.
Flavobacterium psychrophilum is one of the most important pathogens affecting cultured rainbow trout (Oncorhynchus mykiss). Recent information from UK salmonid farms showed country‐wide distribution of genetically and serologically divergent clones, which has hampered the development of a vaccine for rainbow trout fry syndrome. The current study assessed the efficacy of an injectable polyvalent vaccine containing formalin‐inactivated F. psychrophilum in rainbow trout. The vaccine was formulated with an oil adjuvant (Montanide ISA 760VG) or formalin‐killed cells alone. Duplicate groups of trout (60 ± 13 g) were given phosphate‐buffered saline or vaccine formulated with Montanide by intra‐peritoneal (i.p.) injection and challenged by intra‐muscular (i.m.) injection with a homologous and a heterologous isolate of F. psychrophilum at 525 degree days post‐vaccination (dd pv). Significant protection was achieved in vaccinated fish (p = 0.0001, RPS 76% homologous, 88% heterologous). Efficacy of the adjuvanted vaccine was also demonstrated by heterologous challenge at 1155 dd pv resulting in 100% protection, whereas survival in the un‐adjuvanted group was not significantly different from control fish. Levels of specific antibody at 1155 dd pv, as measured by ELISA, were significantly higher in the fish vaccinated with adjuvant when compared with unvaccinated fish.  相似文献   
994.
We describe a case of gastrocnemius muscle rupture in a goral that got caught in a live trap set up to capture wild boars. We established a diagnostic method based on clinical signs and imaging examination findings, including magnetic resonance imaging for gastrocnemius muscle rupture with symptoms such as hindlimb lameness and plantigrade posture of unknown cause in wild animals. Although this condition is rare, this report will help veterinarians diagnose several diseases of the musculoskeletal and nervous systems in wild animals. This is the first report of successful diagnosis and treatment of gastrocnemius muscle rupture in gorals in Korea.  相似文献   
995.
Rainfall, stemflow, and throughfall were collected from 1996 to 1999 at two types of forest sites: (1) forests near the traffic roads and urban areas and (2) forests away from the urban areas at Mt. Gokurakuji, Hiroshima, western Japan in order to estimatethe effects of anthropogenic activities on atmospheric deposition. Rainfall deposition for major ions showed small differences between the sites. The NO3 - and SO4 2-concentrations in stemflow were higher at the urban-facing slope than at the mountain-facing slope. Throughfall deposition of NO3 - and SO4 2- was also higher at urban-facing slopes. Net throughfall (NTF) deposition (throughfall minus rainfall) of NO3 - and SO4 2- accounted for 77 and50% of the total throughfall deposition on urban-facing slopes, respectively, while it accounted for 44 and 23% on themountain-facing slopes, respectively. These results indicated a higher contribution from dry deposition on urban-facing slopes compared to mountain-facing slopes. Atmospheric N (NO3 - +NH4 +) deposition from throughfall was estimated to be around 17–26 kg N ha-1 yr-1 on urban-facing slopes, which was greater than the threshold of N deposition that could cause nitrogen leaching in Europe and the United States. The highload of atmospheric N deposition may be one of the factors bringing about the decline of pine forests on urban-facing slopesof Mt. Gokurakuji.  相似文献   
996.
Pressurized low-polarity water (PLPW) extraction of phenolic compounds from flax shive was investigated using statistically based optimization and the "one-factor-at-a-time" method. Extraction variables examined using central composite design (CCD) included temperature, flow rate, and NaOH concentration of the extracting water. Extraction of phenolic compounds including p-hydroxybenzaldehyde, vanillic acid, syringic acid, vanillin, acetovanillone, and feruric acid was affected by temperature and NaOH concentration; and extraction of all phenolic compounds, except ferulic acid, increased with temperature and NaOH concentration of the extracting water. Flow rate had little effect on concentration of phenolic compounds at equilibrium, but the extraction rate at the early phase was higher for higher flow rates. The mechanism of PLPW extraction of flax shive phenolics was also investigated using a two-site kinetic model and a thermodynamic model. To determine the extraction mechanism, flow rate was varied from 0.3 to 4.0 mL/min while temperature and NaOH concentration were fixed at 180 degrees C and 0.47 M, respectively. The flow rate tests showed the extraction rates of total phenolic (TP) compounds increased with flow rate and can be described by a thermodynamic model. The results from the thermodynamic model demonstrated that a K(D) value of 30 agreed with the experimental data in the flow rate range of 0.3-4.0 mL/min. When the effect of the three independent variables was evaluated simultaneously using CCD, a maximum TP concentration of 5.8 g/kg of dry flax shive (DFS) was predicted from the combination of a high temperature (230.5 degrees C), a high initial concentration of NaOH (0.63 M), and a low flow rate (0.7 mL/min). Maximum TP concentration of 5.7 g/kg of DFS was obtained from extraction conditions of 180 degrees C, 0.3 or 0.5 mL/min, and 0.47 M NaOH at equilibrium. A second-order regression model generated by CCD predicted a maximum TP concentration of 5.8 g/kg of DFS under the same extraction conditions, which is well matched with the results from experimental data.  相似文献   
997.
The volatile compositions in dried white ginseng according to species ( Panax ginseng , Panax notoginseng , and Panax quinquefolius ) were analyzed and compared by applying multivariate statistical techniques to gas chromatography-mass spectrometry data sets. Main volatile compounds of ginseng species in the present study were sesquiterpenes, such as bicyclogermacrene, (E)-β-farnesene, β-panasinsene, calarene, α-humulene, β-elemene, etc. In particular, α-selinene, α-terpinolene, β-bisabolene, β-phellandrene, β-sesquiphellandrene, zingiberene, germacrene D, limonene, α-gurjunene, (E)-caryophyllene, δ-cadinene, (E)-β-farnesene, α-humulene, bicyclogermacrene, longiborn-8-ene, β-neoclovene, and (+)-spathulenol were mainly associated with the difference between P. ginseng and P. notoginseng versus P. quinquefolius species. On the other hand, the discrimination between P. ginseng and P. notoginseng could be constructed by hexanal, 2-pyrrolidinone, (E)-2-heptenal, (E)-2-octenal, heptanal, isospathulenol, (E,E)-2,4-decadienal, 3-octen-2-one, benzaldehyde, 2-pentylfuran, and (E)-2-nonenal.  相似文献   
998.
Abstract

The salt titration (ST) method was evaluated as a method to determine ZPC in comparison with the potentiometric titration (PT) method for 26 soils with variable charge clays, i.e., Oxisols and Ultisols from Thailand and Andisols from Japan. In addition to the determination of ST-pH0 as the zero point of charge, a calculation procedure (STPT method) was adopted here in order to acquire more information from the titration curve. Furthermore, for the purpose of cross-checking of ZPC determined by the PT method, the ST procedure was successively applied to the samples analyzed by the PT method (PTST method).

The soil to solution ratios of 1: 10 to 1: 5 gave almost an identical ST-pH0 value for every soil. The values of both ST-pH0 and PT-ZPC ranged from 4.7 to 6.3 for the Andisols, while for the Oxisols and Ultisols, they were always below 4.2. The difference between the values of ST-pH0 and PT-ZPC was only slight for the Andisols, whereas it was sometimes large (0.4 pH unit) for the Oxisols and Ultisols. Nevertheless, it was concluded that the ST method with its modification (STPT) was comparable to or even better than the PT method for the soil characterization work due to its convenience and simplicity.  相似文献   
999.
在大多数生长试验中,试验动物往往成群地饲养在同一圈中。在试验过程中,有时有个别动物在生长速度上会表现出与其同伴较大的差异,或者死亡。出现此种情况时,如果不能为统计日平均采食量(average daily feed intake,ADFI)和饲料效率而对试验动物的圈采食量(penfeedintake,PFI)进行重新评估,那么试验数据集将丢弃该圈的观察值。因此,我们开发了一个模型,用来评估群体饲喂条件下猪的个体采食量(Individual feed intake,IFI),并通过群体饲喂模拟试验对该评估模型进行验证。在推荐模型中,将每个受影响圈的采食量(FeedIntake,FI)分为用于维持生存需要的采食量(FIm)和用于生长需要的采食量(FIg)两个部分。首先,试验期间个体猪的FIm按NRC(1998)所列出的维持生存所需代谢能的评估方法进行测算,然后将同圈内所有猪的FIm相加,即得到圈FIm。圈采食量(PFI)与圈FIm之差就是该圈动物用于生长所需的那部分采食量。接下来,把该差额部分的采食量平均分给圈内动物每单位增重上,即为FIg。最后,猪圈中被淘汰猪的IFI估测值即为所淘汰猪的FIm与FIg之和,原来的圈采食量(PFI)减去该FI估测值后即得剩余猪的新PFI。个体采食量评估的准确性取决于维持生存代谢能预测方程和饲料原料能量分析值的准确性。在模拟试验中,我们将推荐模型的精确度与2个其它模型的精确度作了比较。模拟试验1显示,在所有测试阶段中推荐模型的精确度至少高于其它2个模型中的任一种方法(P<0.001);模拟试验2也证明,推荐模型的精确度高于其他2种方法。由于IFI的人工计算相对麻烦,为此我们开发了饲料采食量校正电子数据表(feed intake correction spreadsheet,FICS),即一个利用宏指令可对FI进行校正的Excel电子数据表。FISC包括了推荐模型中的所有测算程序,用户可免费从指定的网页上下载Excel文件和使用说明书。  相似文献   
1000.
The diverse therapeutic feasibility of the sea urchin-derived naphthoquinone pigment, Echinochrome A (Ech A), has been studied. Simple and noninvasive administration routes should be explored, to obtain the feasibility. Although the therapeutic potential has been proven through several preclinical studies, the biosafety of orally administered Ech A and its direct influence on intestinal cells have not been evaluated. To estimate the bioavailability of Ech A as an oral administration drug, small intestinal and colonic epithelial organoids were developed from mice and humans. The morphology and cellular composition of intestinal organoids were evaluated after Ech A treatment. Ech A treatment significantly increased the expression of LGR5 (~2.38-fold change, p = 0.009) and MUC2 (~1.85-fold change, p = 0.08). Notably, in the presence of oxidative stress, Ech A attenuated oxidative stress up to 1.8-fold (p = 0.04), with a restored gene expression of LGR5 (~4.11-fold change, p = 0.0004), as well as an increased expression of Ly6a (~3.51-fold change, p = 0.005) and CLU (~2.5-fold change, p = 0.01), markers of revival stem cells. In conclusion, Ech A is harmless to intestinal tissues; rather, it promotes the maintenance and regeneration of the intestinal epithelium, suggesting possible beneficial effects on the intestine when used as an oral medication.  相似文献   
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