Relationship between rectal findings of corpus luteum and whole milk progesterone levels in postpartum dairy cows

The reliability of clinical ovarian findings was assessed as an indicator of luteal function in primiparous dairy cows. The postpartum period of 103 cows following their first parturition was studied by thrice weekly rectal palpation of ovaries and whole milk progesterone assay from 1 week after parturition to the first insemination. The relationship between milk progesterone levels and 1101 ovarian findings was compared during the follicular phases, short luteal phases and during the early, mid and late thirds of normal luteal phases. The compatibility between elevated progesterone and palpable corpus luteum was 71%, and between low progesterone and lack of corpus luteum 77%. In 10% of all rectal examinations the finding was unspecified; i.e. the clinician could not differentiate between luteal and follicular activity. During the acyclic period prior to the initiation of luteal function, the proportion of false corpus luteum findings was 11%. The corpora lutea of the short oestrous cycles were more difficult to palpate than those of normal cycles. During early dioestrus the corpus luteum was significantly more difficult to palpate than during the rest of dioestrus. The percentage of unspecified findings was highest during early dioestrus.The paper discusses the reliability of rectal examination as a method of diagnosing cyclicity and of evaluating the responsiveness of a cow to prostaglandin treatment.     

不同光周期条件下PhyB和ABA对不同苜蓿品种的秋眠性调控

短日照和低温是导致苜蓿秋眠的主要环境因子。本研究检测了3个不同秋眠型苜蓿在8,12和16 h光照光周期条件下叶片和顶芽中PhyB和ABA的含量,并探讨其对秋眠的影响机制。结果表明,1)和非秋眠苜蓿相比,秋眠苜蓿叶片中PhyB含量高,PhyB作为绿色植物主要光受体可能通过光周期调控或参与了苜蓿的秋眠;并且3个品种均是在8 h光照下PhyB合成量高,暗示长暗期利于其合成。2)和12,16 h光照相比,8 h处理顶芽和第一展开叶中ABA含量最高,显然短日照利于ABA的合成;8 h光照处理时,秋眠型苜蓿品种Vernal ABA含量分别比半秋眠型CW5 0 2和非秋眠型CUF1 0 1高2.1 2和2.0 3倍,1 2 h光照处理ABA含量Vernal比CW5 0 2和CUF1 0 1分别高3 6.2 4%和46.46%,但16 h光照处理ABA含量并不表现上述规律,说明8和12 h光照程度不同地为苜蓿创造了逆境效应,ABA可能是调控或诱导秋眠的激素。3)8 h光照下苜蓿秋眠特征明显,生长严重受抑,不开花;12 h光照下苜蓿秋眠特征比8 h光照处理轻,生长受抑但抑制程度低于8 h光照处理,不开花;16 h光照下3个品种生长、开花正常。可能是PhyB含量多寡程度不同地调控了光周期反应,进而影响了ABA合成,而ABA在不同光周期诱导下通过合成量不同调控了不同秋眠基因表达,诱发了秋眠。     

短侧枝挂果核桃优良品种选择

针对云南核桃产业发展中存在的品种混杂,良莠不齐,丰产性能差等问题,开展了核桃(Juglans sig-illata)优良品种的选育工作。经过对核桃各品种的挂果情况的调查研究和品质分析,选出龙佳核桃、宁香核桃2个良种。     

引入冗余函数的基于椭圆曲线的消息恢复签名方案

提出了一种新的基于椭圆曲线的消息恢复签名方案,方案中引入了冗余函数,并对其安全性进行了分析,发现该方案能有效防止伪造攻击.同时该方案具有通信成本低、通信速度快、安全性高等特点,适合小型身份认证系统.     

Seasonal and age effects on energy requirements in domestic short‐hair cats (Felis catus) in a temperate environment

There is little information known about the energy requirements of cats in temperature climates. Energy requirement of domestic short‐haired cats was determined using three groups of mixed gender – old kept outside (approximately 9.9 years of age; 4.8 kg; n = 9), young kept outside (approximately 3.1 years of age; 3.9 kg; n = 8) or young kept inside (approximately 3.1 years of age; 3.9 kg; n = 8). Cats were housed individually for 5 weeks during summer (18.5 ± 0.5 °C) and winter (8.5 ± 0.4 °C) and were fed a commercially available maintenance diet ad libitum. In both periods, energy expenditure was determined from the rates of ²H and ¹⁸O elimination for blood H₂O over a 12 day period, from a doubly labelled water bolus ²H₂O (0.7 g/kg BW) and H₂¹⁸O (0.13 g/kg BW) administered intravenously. During the summer period, macronutrient digestibility was determined. Older cats had a reduction (p < 0.05) in apparent digestibility of dry matter (approximately 9%), energy (approximately 8%) and protein (6%). There was a significant effect of age and season on energy intake and energy expenditure. While lean mass was affected by age and season, there was no effect of age or season on energy expenditure when expressed as a proportion of lean mass. Possible seasonal differences in nutrient digestibility may explain these results.     

短链葡聚糖-姜黄素纳米乳液的制备及结构表征

利用短链葡聚糖(short glucan chains,SGC)的螺旋空间结构来包埋姜黄素(curcumin,CUR)。通过使用高剪切分散乳化机高速剪切溶液5 min,用纳米均质机在50 MPa压力下高压均质经剪切后的乳液2次制备成纳米乳液以提高其包埋率和载药量。XRD (x-ray diffraction)和TGA (thermogravimetric analysis)很好的验证了包合物的形成,通过TGA、SEM (scanning electron microscopy)、激光粒径分析仪等各种表征分析得出短链葡聚糖-姜黄素纳米乳液制备成功,所制得的乳液对姜黄素的包埋率和载药量都高于短链葡聚糖-姜黄素包合物,分别达到了71.11%和12.07%,说明制备成纳米乳液对姜黄素的包埋率和载药量都有了明显的提高。所制备的纳米乳液的粒径小于300 nm,粒径分布均一,Zeta电位观测表明所制得的乳液的稳定性有所提高。为提高食品及医药领域姜黄素的生物利用率提供了一定的参考意义。     

外源添加短链脂肪酸调控断奶前犊牛胃肠道健康发育潜在功能和机制

胃肠道健康发育是影响犊牛生长及其潜在生产性能发挥的关键。研究报道,短链脂肪酸(SCFA)和胃肠道微生物可促进幼龄动物胃肠道健康发育,但具体机制还不明确。新生犊牛胃肠道发育不健全,胃肠道内微生物种类及丰度均较低,内源性产生的代谢产物SCFA较少。现有文献表明,SCFA具有通过影响断奶前犊牛胃肠道微生物的定植、维持肠道黏膜屏障的完整性及提高肠道抗炎能力,进而促进犊牛胃肠道健康发育的功能。本文拟从胃肠道上皮和微生物2个层次来探究并综述外源添加SCFA促进断奶前犊牛胃肠道发育的分子机制,及其对断奶前犊牛胃肠道微生物定植的影响及机理,为犊牛健康培育与科学饲养提供理论基础。     

The production of short chain fatty acid and colonic development in weaning piglets

Weaning process widely affects the small intestinal structure and function in piglets, while the responses of large intestine to weaning stress are still obscure. The purpose of this study was to determine the developmental changes (i.e., short chain fatty acids (SCFAs) concentrations, growth parameters, crypt‐related indices and antioxidant capacity) in colon of piglet during weaning. Forty piglets were weaned at day 21 and euthanized to collect colonic tissues and digesta samples on day 0, 1, 3, 7 and 14 post‐weaning (n = 8). Piglet growth performance was improved (p < .001) on day 7 and 14 post‐weaning. The concentrations of acetate, propionate, butyrate, valerate, isobutyrate, isovalerate and total SCFAs were higher (p < .001) during the late post‐weaning period. The mRNA abundances of SCFAs transporters were greater (p < .001) on day 7 and 14. The absolute and relative weights, absolute length and perimeter of colon were greater (p < .001) on day 7 and 14. Similarly, post‐weaning increases (p < .001) in colonic crypt depth and Ki67 positive cells numbers per crypt were observed during the same period. Colonic crypt fission indices decreased (p < .01), while total crypt numbers increased (p < .001) on day 14 after weaning. Moreover, total SCFAs concentration was significantly associated with colonic growth parameters and Ki67 cells/crypt (p < .001). In addition, catalase content was decreased on day 3, 7, and 14, whereas, the concentrations of total superoxide dismutase (T‐SOD) and manganese‐containing superoxide dismutase (MnSOD) were higher (p < .05) on day 1 and 3 post‐weaning. These results showed that weaning process has a significant effect on colonic growth and development, which might be associated with the change of SCFAs concentrations in colon.     

神经系统中心理信息运作过程和机理

生命的本能是能够把非实体信息转换成实体信息,并以此主动地支配和调节生命主体的行为,这应该就是生命奥秘的关键。心理信息内容作为实体信息被直接固化到神经子网络系统中,该实体信息能够完全替代外来信息表现心理内容。神经系统能够在心理信息运行的过程中自然而然地形成必要的记忆,人体内的精巧机制能够控制心理信息有目的地运行。     

动力负熵场及其在短期天气预报中的应用

把纬圈气流虚拟平衡态原理具体应用到短期预报中,因时效短的缘故,决定了虚拟平衡态应在低层大气中寻找,倘若时效达到一定天数,则平衡态应在中层大气中定义。按照涡动原理计算出动力负熵值,由动力负熵值构成动力负熵场,其由正熵区,负熵区、０值线三部分组成,正熵区为无降水区,负熵区又分为负熵有效区和负熵无效区,前者为未来的降水区域,降水强度与负熵中心值和梯度的大小成正比。