Effect of treating alfalfa silage with pistachio by‐products extract on Saanen dairy goats performance and microbial nitrogen synthesis

A lactation experiment was conducted to determine the influence of addition of pistachio by‐products extract (PBE) to alfalfa silage (AS) on performance, rumen fermentation, milk yield and composition, and microbial nitrogen synthesis. Eight multiparous dairy goats (1.8 ± 0.25 kg of milk yield) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments to compare two types of AS (supplemented with or without PBE) with two levels of dietary crude protein (14% vs. 16% CP). Dietary treatments were (i) AS with 14% CP of DM diet without PBE (14%CP?PBE), (ii) AS with 14% CP of DM diet with PBE (14%CP + PBE), (iii) AS with 16% CP of DM diet without PBE (16%CP?PBE) and (iv) AS with 16% CP of DM diet with PBE (16%CP + PBE). PBE was sprayed on fresh alfalfa at a ratio of 500 ml/kg alfalfa DM to get the final concentration of 1% tannin as tannic acid equivalent on DM basis. Intake of CP was greater (p < 0.01) in goats fed 16% CP diets than those fed 14% CP diets, regardless of PBE supplementation. Supplementation of PBE tended to decrease (p = 0.09) rumen NH₃‐N concentration regardless of the level of CP in the diet. Supplementation of PBE tended (p = 0.09) to decrease total purine derivatives regardless of the level of CP in the diet with no significant change in microbial nitrogen supply. Efficiency of microbial nitrogen synthesis (EMNS) had a tendency (p = 0.07) to decrease in PBE supplemented diets. There was also a tendency (p = 0.10) for more EMNS in 14% CP fed goats than those fed 16% CP diets. Therefore, AS supplemented with PBE may lead to less concentration of ruminal NH₃‐N because of decreased degradation of CP by rumen micro‐organisms in response to pistachio by‐products tannins.     

Effect of dietary energy on digestibilities,rumen fermentation,urinary purine derivatives and serum metabolites in Tibetan and small‐tailed Han sheep

Tibetan sheep are indigenous to the Qinghai–Tibetan Plateau, graze the grassland all year round without supplementation and are well‐adapted to the harsh conditions. Small‐tailed Han sheep were introduced to the plateau and are raised mainly in feedlots. Based on their different backgrounds, we hypothesized that the ability to cope with poor diets would be better in Tibetan than in Han sheep. To test our prediction, we examined the effect of dietary energy on apparent digestibilities, rumen fermentation, urinary purine derivatives and serum metabolites by using a 4 × 4 Latin square design in each sheep breed. Four diets were formulated to be low in crude protein (~7%) but to differ in metabolizable energy concentration. Average daily gain was greater in Tibetan than in Han sheep (p < 0.01) and increased linearly with an increase in energy intake (p < 0.001). The digestibilities of dry matter, organic matter, gross energy, and neutral and acid detergent fibres were greater in Tibetan than in Han sheep (p < 0.05). Ruminal pH was lower (p < 0.05), while volatile fatty acids (VFAs), urea‐N, ammonia‐N and soluble protein‐N concentrations were higher (p < 0.05) in Tibetan than in Han sheep. As a molar proportion of total VFA, acetate decreased (p < 0.001) with an increase in dietary energy whereas propionate and butyrate increased (p < 0.05). Urinary purine derivative excretion was greater in Tibetan than in Han sheep (p < 0.01), as was microbial nitrogen production; both parameters increased with dietary energy (p < 0.01). Serum concentrations of glucose, insulin and insulin‐like growth factor‐1 increased (p < 0.05) as energy level increased, while non‐esterified fatty acids and growth hormone decreased (p < 0.05). It was concluded that Tibetan sheep were better able to cope with low‐protein, low‐energy diets and, consequently, our prediction was supported.     

基于小波神经网络的气温预测研究

主要参考温度信号的固有特性,以1951～2014年的重庆市温度数据为例,使用小波神经网络(WNN)对温度进行预测估计.实证结果表明,该研究建立的小波神经网络能够对未来气温进行较好的预测,进而可应用于天气衍生品定价等领域,实现对冲天气风险.     

SUBGRADIENT OF SET-VALUED MAPPING

This paper presents a new subgradient of set-valuedmapping and discusses its close properties and its no empty convexproperties.Under proper conditions,it proves to be true.     

三种噻二唑衍生物对小麦幼苗生理特性的影响

用不同浓度(0、6、8、10、12、14 mg/L)的3种新合成的噻二唑衍生物(5-对氯苯基-2-邻氯苯甲酰胺基-1,3,4-噻二唑、5-对氯苯基-2-邻硝基苯甲酰胺基-1,3,4-噻二唑、5-对硝基苯基-2-对甲基苯甲酰胺基-1,3,4-噻二唑)对小麦幼苗进行处理,研究了它们对小麦幼苗部分生理特性的影响.结果表明,经3种噻二唑衍生物处理后小麦幼苗叶片的可溶性蛋白质及叶绿素含量比对照显著增加,叶片的硝酸还原酶活性以及根系活力也显著提高.表明噻二唑衍生物处理对小麦幼苗生理活性具有明显的促进效应,3种噻二唑衍生物中以5-对氯苯基-2-邻硝基苯甲酰胺基-1,3,4-噻二唑的促进效应较为明显.     

紫草素及其衍生物的生物合成与药理研究进展

天然紫草素类化合物具有消炎、抗菌、抗病毒和抗肿瘤等功效。由于活性广谱,近年来对其研究众多,涌现出大量的研究成果。该文就紫草素及其衍生物活性和生物合成方面近十几年的研究进行归纳和总结,并着重对天然紫草素类化合物与紫草素类合成衍生物的抗肿瘤活性进行比较,从而为紫草素及其衍生物活性的进一步研究提供可能的依据。     

-石竹烯及其衍生物的生物活性与合成研究进展

综述了β-石竹烯及其衍生物的活性及合成方法。在活性方面,β-石竹烯作为香料已经被应用于化妆品和食品添加剂中,药理研究表明β-石竹烯具有局麻作用、抗炎作用、驱蚊虫作用、抗焦虑、抗抑郁作用,β-石竹烯醇还应用于镇咳祛痰药物中,石竹烯氧化物具有镇痛和抗炎作用,抗真菌作用,还有细胞毒性等。同时还简单介绍了β-石竹烯及其部分衍生物的合成方法。     

Effects of isovalerate on ruminal fermentation,urinary excretion of purine derivatives and digestibility in steers

The objective of this study was to evaluate the effects of isovalerate supplementation on rumen fermentation, urinary excretion of purine derivatives and feed digestibility in the total tract of steers. Eight ruminally cannulated Simmental steers were used in a replicated 4 × 4 Latin square experiment. The treatments were: control (without isovalerate), low isovalerate (LIV), medium isovalerate (MIV) and high isovalerate (HIV) dosage of isovalerate at 100, 200 and 300 mg isovalerate per kg dry matter (DM) intake respectively. Diets consisted of corn stover and concentrate (60/40, DM basis). Dry matter intake was approximately 9 kg per day that was 90% of ad libitum intake including 5.4 kg corn stover and 3.6 kg concentrate. Ruminal pH (6.72–6.54) was linearly (p < 0.03) reduced, whereas total volatile fatty acid concentration (64.6–74.7 mmol/l) was linearly (p < 0.01) and quadratically (p < 0.01) increased with increasing isovalerate supplementation. Ratio of acetate to propionate increased linearly (p < 0.01) from 2.78 to 3.39 as isovalerate supplementation increased because of the increase in acetate production and decrease in propionate production. In situ ruminal degradation of amylase‐treated neutral detergent fibre (aNDF) of corn stover was improved, but crude protein (CP) degradability of soybean meal decreased with increasing isovalerate supplementation. Urinary excretion of purine derivatives was quadratically (p < 0.01) changed by altering isovalerate supplementation (50.5, 54.3, 58.9 and 55.2 mmol/day for control, LIV, MIV and HIV, respectively). Similarly, digestibilities of organic matter, aNDF and CP in the total tract were linearly and quadratically increased with increasing isovalerate supplementation. The results of this study indicate that supplementation of diet with isovalerate improved ruminal fermentation and feed digestion in beef cattle. It was suggested that the isovalerate stimulated the digestive micro‐organisms or enzymes in a dose‐dependent manner.     

Synthesis and bioactivity evaluation of novel spiromesifen derivatives

BACKGROUND: The development of environmentally friendly and novel structural pesticides is now an area of intense research in the agriculture field. Spirocyclic tetronic acids such as spiromesifen are typical compounds of this kind. In order to discover novel compounds with improved and broader-spectrum insecticidal activities, a series of spiromesifen derivatives were synthesised and bioassayed. RESULTS: The derivatives were identified by ¹H NMR and MS. Preliminary bioassays demonstrated that some bioactivities of compounds 5a to 5u were better and had a broader spectrum than the lead compound spiromesifen. Moreover, these compounds showed better insecticidal activities against Mythimna sepatara and Aphis fabae than acaricidal activities against Tetranychus cinnabari. Furthermore, LC₅₀ of 5s against Aphis fabae reached 1.09 mg L⁻¹. At the same time, compounds 5g, 5i, 5k and 5r also warrant further study because of their superior bioactivities to spiromesifen. What is more, suitable carbon chain length in the 4-position ester and the log P value of these spiromesifen derivatives dramatically influenced their insecticidal activities. Butyric or pentanoic ester and a log P value of 4.0–6.0 may be preferred. CONCLUSION: The present work demonstrates that some spiromesifen derivatives can be used as potential lead compounds for developing novel insecticides and acaricides. Copyright © 2011 Society of Chemical Industry     

金融衍生工具在企业理财中的应用

当今社会越来越多的企业利用金融衍生工具理财,对金融衍生工具的研究已经成为财务管理理论界和实务界研究和关注的热点问题。文章从研究企业利用金融衍生工具理财的基本原理出发,概括了金融衍生工具的定义及其分类,阐述了企业利用金融衍生工具理财的必然性,并以具体案例为载体,重点论述了金融衍生工具在企业筹资管理和投资管理中的具体运用,最后分析了企业理财中选择金融衍生工具应注意的几个问题。