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1.
Jianping Li Maowang Jiang Qingxi Han Ruibing Peng Xiamin Jiang 《Aquaculture Nutrition》2020,26(4):1026-1034
This study evaluated the effects of dietary γ‐aminobutyric acid (GABA) on the growth performance, serum biochemical indices and antioxidant status of pharaoh cuttlefish, Sepia pharaonis. Cuttlefish were cultured in open‐culturing cement pool systems for 8 weeks. Six practical diets supplemented with graded levels of GABA (0, 20, 40, 60, 80 and 100 mg/kg) were formulated. Each diet was randomly assigned to triplicate groups of 60 cuttlefish (mean weight: 10.33 g), the cuttlefish were fed two times per day to apparent satiation. The results showed that the specific growth rate (SGR), weight gain (WG) and feed efficiency (FE) significantly increased with dietary GABA supplementation (p < .05). The survival rate (SR) and protein content in muscle significantly increased when 58.9 mg/kg GABA supplied. Moreover, the nitric oxide (NO) content and acid phosphatase (ACP) activity in serum were significantly increased with dietary GABA supplementation (p < .05), while the activity of aspartate aminotransferase (AST) in serum decreased significantly when supplied with GABA at 58.9 mg/kg (p < .05). In addition, dietary GABA improved antioxidation activity by significantly increasing the activities of superoxide dismutase (SOD) and catalase (CAT) but decreasing malondialdehyde (MDA) levels in the liver and gill (p < .05). On the basis of the quadratic regression analysis of FE, the optimum content of dietary GABA in S. pharaonis was estimated to be 55.3 mg/kg. The findings of this study demonstrated that dietary GABA had a positive effect on the growth performance, serum biochemical indices and antioxidant status of S. pharaonis. 相似文献
2.
The diagnosis and recommendation integrated system (DRIS) approach was used to interpret nutrient analyses of leaf tissues from pomegranate cv. Bhagwa orchards grown in southwestern Maharashtra, India. The DRIS norms were established for three growth stages,viz. 50% flowering, fruit development and first harvesting of pomegranate. Various nutrient ratios were obtained from high-yielding population and were used to compute DRIS indices for diagnosing nutrient imbalances and their order of limitation to yield. Nutrient sufficiency ranges at 50% flowering derived from DRIS norms were 1.32–2.15% nitrogen (N), 0.18–0.24% phosphorus (P), 1.29–1.99% potassium (K), 0.64–1.20% calcium (Ca), 0.23–0.45% magnesium (Mg), 0.16–0.26% sulfur (S), 103.04–149.12 mg kg?1 iron (Fe), 39.60–72.85 mg kg?1 manganese (Mn), 15.99–26.10 mg kg?1 zinc (Zn), 6.16–9.32 mg kg?1 copper (Cu), 23.38–39.88 mg kg?1 boron (B) and 0.29–0.47 mg kg?1 molybdenum (Mo). Similarly, the sufficiency range at fruit development and first harvesting was developed for computing DRIS indices. The requirement of Fe, Mg, S, Zn and N by the pomegranate plant was higher at 50% flowering and fruit development stages. According to these DRIS-derived indices, 87.85, 73.83, 70.09, 69.16 and 65.42% orchards were deficient in Fe, S, Mg, Zn, and N, respectively, at 50% flowering, while 70.03, 66.36, 63.55, 61.68, and 68.22% orchards were found to be deficient in respective nutrients during the fruit development stage. 相似文献
3.
Analysis of wheat grain development using NIR spectroscopy 总被引：1，自引：0，他引：1
The scope of the present investigation was to detect maturation processes in wheat seed non-destructively with special respect to changes in moisture, carbohydrate and protein content and natural hydration/dehydration processes. During seed development, many biochemical, enzymatic and morphological changes occur under highly hydrated conditions. 相似文献
4.
Bruno Vila Franck Torre Frdric Guibal Jean-Louis Martin 《Forest Ecology and Management》2003,180(1-3):413-424
Taking advantage of the introduction of the black-tailed deer to the Queen Charlotte Islands (British Columbia, Canada), we used dendrochronological analyses to understand the consequences of deer browsing on Sitka spruce growth. We compared shape, radial growth, height growth and age of young spruce in three sites. We identified two types of trees growing side by side: (1) stunted and heavily browsed spruce, smaller than the browsing limit and (2) escaped spruce that were taller than the browsing limit but still browsed in their lower part. The compact and heavily ramified shape in stunted spruce was the result of repeated and intense browsing. In escaped spruce this was also the case below the browsing limit (1.16 m±0.07 m), in sharp contrast with the normal shape that escaped spruce resumed above the browsing limit. We show that the release of browsing pressure, once the tree reaches the browsing limit, is characterised by an abrupt increase in radial growth. Before release, trees show a growth stagnation characterized by narrow rings (0.5 mm per year) and small annual height increments (<5 cm per year). After release, trees show a growth stabilisation characterised by wider rings (3 mm per year) and larger annual height increments (20 cm per year). We use this pattern to estimate frequency and age at release and their possible variation over time. Age differences between stunted and escaped spruce are highly significant and indicate that, despite of browsing, most if not all trees will ultimately reach the browsing limit and escape. Heavy deer pressure (30 deer per km2) delays spruce sapling recruitment by about 8 years. This delay varies in relation to site quality and seems to have increased over time, suggesting an increase in browsing pressure. 相似文献
5.
The main purpose of this study was to investigate the changes in heat flux and temperature after the subject's palm was in contact with interior decorating materials. The relations among heat flux, temperature, and sensation of cold/warm during contact were studied. Ten men and ten women were selected and introduced to 21 materials for the contact test. They were in contact with the specimens for 30min without seeing them in a climate-controlled room at 25°±1°C and 65% RH. Changes in the heat flux and temperature of the specimens were determined by a heat flux meter. A sensory evaluation test was applied to evaluate the cold-warm contact. Results indicated that the heat flux and temperature increased with increasing time after the subject's palm was in contact with the specimens. The heat flux (Q30) and temperature (T30) 30min after the subject's palm contacted the specimens were greater for male subjects than for female subjects. A positive linear regression equation existed between the values for Q30 andT30, whereas a negative linear regression formula existed the sensation of cold-warm by contact (5) and the values of ln(Q1·). Therefore, the sensation of cold/warm by contact could be estimated simply by using the thermal physical properties of the interior decorating materials.Part of this report was presented at the International Conference on Effective Utilization of Plantation Timber, Chi-Tou, Taiwan, ROC, May 1999 相似文献
6.
Walter Svinurai Abubeker Hassen Eyob Tesfamariam Abel Ramoelo 《Grass and Forage Science》2018,73(3):727-739
Accurate and near‐real‐time estimation of herbaceous aboveground biomass (AGB) at farm level is crucial for monitoring pasture production and proactive management of stock in semiarid rangelands. Despite its importance, remote sensing has been rarely used by range ecologists and managers in Zimbabwe. This study aimed at assessing the performance of classical multispectral vegetation indices (MVIs) when either singly regressed with measured herbaceous AGB or combined with other visible spectral bands in predicting herbaceous AGB in a Colophospermum mopane savannah. Field herbaceous AGB and corresponding Landsat 8 Operational Land Imager visible spectral data were collected during the 2016–2017 rainy season. Relationships between measured AGB and classical MVIs and extended models of MVIs combined with other visible bands were analysed using bootstrapped simple and stepwise multiple linear regression functions. When MVIs were singly regressed with measured AGB, ratio‐based indices yielded the highest r2 value of 0.64, followed by soil‐adjusted indices (r2 = 0.61), while atmospherically corrected MVIs showed the lowest r2 of 0.58 (p = 0.00). A significant improvement in herbaceous AGB estimation was obtained using a combination of MVIs and other visible bands. Soil‐adjusted MVIs showed the greatest increase (44–46%) in r2, while atmospherically corrected and ratio‐based MVIs poorly improved (<5%). The findings demonstrate that combining MVIs with Landsat 8 optical bands, especially green band, provides the best models for estimating AGB in C. mopane savanna rangelands. These findings emphasize the importance of testing band‐MVI combinations when developing models for estimating herbaceous AGB. 相似文献
7.
《Communications in Soil Science and Plant Analysis》2012,43(4):331-339
Abstract A field experiment was conducted on an alkaline calcareous soil of Agronomy farm of the College of Agriculture, University of Udaipur to study the effect of sulphur on crop yield, leaf elemental composition, chlorophyll synthesis and activities of haematin enzymes. Application of elemental sulphur 21 days before planting with and without 0.1 per cent foliar sprays of H2SO4. increased crop yield by 137 to 197 per cent. Application of all these treatnents had no effect on nitrogen, phosphorus and potassium content of leaves but sulphur content was signficantly increased. Iron content of green leaves was decreased significantly 4 to 5 times together with an increase in the activity of catalase and peroxidase enzymes. Chlorosis in these soils appears to be on account of a reduced physiological availability of iron after absorption. 相似文献
8.
探讨ABA溶液预处理蝴蝶兰类原球茎(PLB)对耐脱水性及生理学基础的效应,本实验观测H2O和ABA溶液分别预处理PLB的脱水成活率及脱水前后的相关生理指标。结果表明,80μmol/L的ABA溶液预处理PLB,显著降低失水速度,极显著提高脱水后成活率。新鲜PLB、H2O或ABA溶液浸泡的PLB三者之间的干物质重量、相对电导率和成活率均无显著差异。ABA溶液预处理能极显著提高PLB可溶性蛋白、热稳定蛋白、可溶性糖和蔗糖含量,明显地降低还原糖含量,也能使PLB的SOD活性极显著提高,POD、CAT活性均极显著降低,但总抗氧化能力极显著提高。所以,ABA溶液短时间处理蝴蝶兰PLB并不能明显改变重量和造成损伤,预处理能提高脱水保护物质含量和总抗氧化能力水平,是增强PLB脱水耐性的基础。 相似文献
9.
随着社会经济的快速发展,生存环境的持续恶化,越来越多的人出现健康问题。现代医学和药理学的很多研究都表明,猴头菇多糖具有降血压、抗肿瘤、抗衰老、降血脂、提高免疫力等多种生理功能。对猴头菇多糖的提取方法进行了着重阐述,并综述了目前国内外对猴头菇多糖的生理功能及其开发应用的最新研究进展,同时对其发展前景进行了展望,以期为猴头菇的深度开发利用提供理论依据。 相似文献
10.
[目的]分析氟中毒对獭兔机体生理功能的影响,为獭兔氟中毒提供血液生理诊断依据。[方法]以9只体重2．O-2．5kg的健康成年獭兔为试验对象,采用氟化钠溶液灌胃建立獭兔氟中毒模型,对试验兔采血测定血液生理指标,比较獭兔氟中毒前后血液相关生理指标、体重、精神状态等变化,分析氟对獭兔机体血液生理功能的影响。[结果]獭兔氟中毒后,獭兔红、白细胞、血小板、中性白细胞、淋巴细胞、单核细胞数与对照组相比明显降低（P〈0．01）;嗜酸性、嗜碱性白细胞数明显增多（P〈0．01）;血红蛋白含量、红细胞比容明显降低。血细胞沉降率明显升高（P〈0．05）;大部分红细胞膜形态出现不规则的星芒状突起。[结论]氟中毒对獭兔血液生理功能有明显的影响。 相似文献