Atmospheric humidity and genotype are key determinants of the diurnal stomatal conductance pattern

Great understanding of the genotypic difference in diurnal stomatal conductance (g_s) pattern and the key determinants of the pattern is important for saving water by adopting cultivars appropriately. Fifteen wheat genotypes were studied under different soil conditions and various meteorological conditions with pot cultivation in rain shelter for two years. Genotype and air humidity were found to be key determinants of diurnal g_s pattern. All genotypes under low relative humidity (LRH) and most genotypes under high relative humidity (HRH) displayed a gradual decline pattern from morning through the afternoon. Under moderate relative humidity (MRH), all genotypes present a single-peak curve pattern, but they differed in peak time, which may lead to unreliable g_s comparison between genotypes and get ostensible contrasting materials. The stomatal conductance was significantly different among genotypes under LRH and the increased g_s magnitude is also significantly different when it was compared between LRH and HRH. The present results provide new thinking for selecting and adopting appropriate cultivars with specific stomata traits for the area with various meteorological conditions.     

Relevance of Osmotic and Frost Protecting Compounds for the Winter Hardiness of Autumn Sown Sugar Beet

The cultivation of autumn sown sugar beet (winter beet) is supposed to result in a marked yield increase compared with spring sown sugar beet. Although the importance of the growth stage reached before winter for the survival of autumn sown sugar beet has already been shown, it is not clear to which extent osmotic and potentially frost protecting compounds may contribute to winter hardiness. The study thus aimed to analyse the acclimatization process of sugar beet to low temperatures and to identify compounds which are important for survival of frost. Field trials with autumn sown sugar beet were conducted at eleven environments in Germany from 2009/10 to 2012/13, which were accompanied by greenhouse experiments with controlled temperature regimes. In the field trials, the survival rates after winter varied from 0 % to 99 %, but only in four environments differences between the five genotypes occurred. During acclimatization, betaine, glutamine, proline and raffinose were markedly accumulated and osmolality was enhanced. In particular betaine, amino acids and osmolality showed a positive correlation to the survival rate and were thus identified as potentially frost protecting substances for sugar beet. In contrast, raffinose and proline seem to act rather as stress indicators as they were negatively related to survival. Possible frost protecting substances were identified which can be used in breeding to improve the winter hardiness of sugar beet.     

Preliminary Study on NF-κB Signaling Pathway Regulating Brucella Intracellular Survival Molecular Mechanisms

By the infection of Brucella virulent strain and attenuated strain in mice macrophage RAW264.7,the assay was aimed to explore the relationship between NF-κB signaling pathways and Brucella virulent strain and attenuated strain in intracellular survival.Use different MOI Brucella (2308,RB51,16M and M5) to infect mice macrophage RAW264.7,after 0,4,8 and 24 h infected,cracking cell and collecting supernatant,we detected the effect of Brucella on activation of NF-κB signaling pathway by Western blotting.Different concentrations of NF-κB signaling pathway inhibitor were incubated with mice macrophage RAW264.7,with different multiplicities of infection (MOI) of Brucella infecting cells,ELISA kits to detect the expressions of TNF-α,IL-1β and IL-6 cytokine;At the same time,count the number of intracellular bacteria of CFU.The results showed that rough cattle Brucella strains RB51 could strongly activate NF-κB signaling pathway,smooth cattle Brucella strains 2308 was weak in the activation;At the same time,the activation of NF-κB signaling pathway was concentration dependent.When the MOI was 80,infection time was 8 h,NF-κB activation degrees of rough cattle Brucella strains RB51 and smooth cattle Brucella strains 2308 were the strongest,and this pathway was involved in producing TNF-α and IL-6;NF-κB signaling pathway inhibitor BAY11-7082 affected Brucella intracellular survival.So rough cattle Brucella strains RB51 intracellular survival and NF-κB signaling pathway activity were closely related.The results laid the foundation for the further study of Brucella intracellular pathogenesis,also provided scientific basis for the research of new drugs to Brucella,and prevention and treatment of brucellosis.     

低温驯化对南方小花蝽冷藏的影响

为探讨低温驯化对南方小花蝽雌成虫冷藏的影响，在室内15℃下饲养7 d作为低温驯化处理，研究了驯化后与未驯化的南方小花蝽雌成虫分别在4、6和10℃下冷藏其寿命、存活率和致死中时间（LT₅₀）的异同。结果表明，无论是否进行低温驯化，南方小花蝽雌成虫的寿命都显著大于对照（25℃下饲养）。在10℃冷藏条件下，是否经过低温驯化对南方小花蝽雌成虫寿命没有明显影响，但在4℃和6℃条件下，低温驯化能明显延长雌成虫的寿命，分别延长了80.7%和83.7%。南方小花蝽雌成虫存活率均随冷藏时间的延长而下降，在同一低温冷藏温度下经低温驯化处理的南方小花蝽存活率比未驯化的高。经低温驯化的南方小花蝽雌成虫在4、6和10℃冷藏时，其LT₅₀分别比未经驯化的延长了30.0%、57.8%和40.4%。以上结果表明南方小花蝽的寿命具有可塑性，低温驯化有利于南方小花蝽的冷藏，6℃可作为南方小花蝽长期储藏的温度。     

Does sand content in spawning substrate result in early larval emergence? Evidence from a lithophilic cyprinid fish

The spawning success of lithophilic salmonids is strongly influenced by the fine sediment content (“fines”) of spawning substrates, yet knowledge on the impacts of fines on the spawning of non‐salmonid lithophiles remains limited, despite their ecological and socio‐economic importance in European rivers. Consequently, the aim here was to use an ex‐situ experiment to investigate the impact of sand content on egg survival and timing of larval emergence of the surface‐spawning cyprinid European barbel Barbus barbus. Thirty incubator boxes within a recirculating system were filled with one of five experimental sediment mixtures (0%–40% sand by mass) that each contained 300 fertilised eggs at a depth of 50 mm. Emerged, free‐swimming larvae were captured and counted daily to assess grain‐size effects on larval survival and emergence. Specifically, total proportion of emerged larvae, cumulative daily proportion of emerged larvae and time required to reach 50% emergence were measured during the study. Whilst the proportion of sand in the sediments did not have a significant impact on egg‐to‐emergence survival (mean survival per treatment 75%–79%), it significantly affected the timing of larval emergence to the water column; early emergence was detected in treatments with elevated sand content (on average, 50% emergence after 12–13 days versus 19 days in the control). Similar to findings from salmonid studies, these results suggest high sand content in spawning gravels can influence timing of larval emergence and potentially cyprinid lithophilic fish survival.     

应用Excel软件分析敌敌畏农药对两广二号家蚕的安全间隔期

应用Excel软件中的曲线方程分析判断敌敌畏农药对两广二号家蚕的安全间隔期。结果表明：敌敌畏1000倍液的安全间隔期是6d多，其数学模型为幂函数曲线方：y=88．0653x-1834本方法克服以往家蚕的农药安全期无数学模型可循或使用的BASIC方法陈旧繁杂的缺点，也避免英文统计软件SPSS难以在农村普及的不足，是一种计...     

儒商与企业伦理

为了统计和分析一个国家和地区的收入分配情况，经济学界往往通过入户调查获得家庭收入与消费等数据，采用洛伦兹曲线模型来进行数据拟合.洛伦兹曲线模型拟合效果的好坏，直接影响着收入分配的描述.本文构建了一类凹凸组合的洛伦兹曲线模型，并针对19个国家的收入分配数据进行了实证分析.结果显示该模型具有较好的拟合效果，其基尼系数能较好地描述收入分配现状，对反映和监测居民之间的贫富差距具有重要意义.     

Ecological implications of motor oil pollution: Earthworm survival and soil health

The nontarget effects of fresh and used motor oil were studied in a soil test system involving such criteria as earthworm survival, response of soil dehydrogenase and urease, and nitrification. When earthworms were exposed to motor oil-contaminated soil for 4 weeks, the observed median lethal concentrations (LC₅₀) were 40.33 and 3.88 g kg⁻¹ soil for fresh and used oil, respectively. Only fresh motor oil application increased earthworms' body weight even at the higher dose of 19 g kg⁻¹ soil. Gas chromatography/mass spectrometry revealed that used motor oil contained more of aromatic hydrocarbons and heavy metals than fresh oil. This disparity in the chemical composition might be the factor responsible for the significant toxicity of used motor oil towards earthworms. Activities of soil dehydrogenase and urease were significantly enhanced in presence of both the motor oils, while there was a significant inhibition in nitrification by the used motor oil even at a low concentration of 0.2 g kg⁻¹ soil. This study clearly demonstrated that earthworm survival and nitrification could serve as suitable indices to assess motor oil pollution in soil.     

Estimation of Crown Temperature of Winter Wheat and the Effect on Simulation of Frost Tolerance

Accurate estimation of winter wheat frost kill in cold‐temperate agricultural regions is limited by lack of data on soil temperature at wheat crown depth, which determines winter survival. We compared the ability of four models of differing complexity to predict observed soil temperature at 2 cm depth during two winter seasons (2013‐14 and 2014‐15) at Ultuna, Sweden, and at 1 cm depth at Ilseng and Ås, Norway. Predicted and observed soil temperature at 2 cm depth was then used in FROSTOL model simulations of the frost tolerance of winter wheat at Ultuna. Compared with the observed soil temperature at 2 cm depth, soil temperature was better predicted by detailed models than simpler models for both seasons at Ultuna. The LT50 (temperature at which 50 % of plants die) predictions from FROSTOL model simulations using input from the most detailed soil temperature model agreed better with LT50 FROSTOL outputs from observed soil temperature than what LT50 FROSTOL predictions using temperature from simpler models did. These results highlight the need for simpler temperature prediction tools to be further improved when used to evaluate winter wheat frost kill.     

利用Wood模型拟合中国荷斯坦牛乳脂率变化的效果分析

为了解中国荷斯坦牛乳脂率变化规律,本文利用Wood模型对我国南方5个大中型奶牛场2008~2010年1~3胎中国荷斯坦牛33 194条测定日乳脂率进行曲线拟合。结果表明:中国荷斯坦牛乳脂率变化曲线为典型的倒抛物线形,第一胎拟合度最高(0.9820),第三胎最低(0.9789)。二胎牛乳脂率最先达到最低点(第16周),而三胎乳脂率最后达到(第19周)。就最低乳脂率而言,二胎牛最大(3.54%),而三胎牛最小(3.45%)。综合各方面情况得出,Wood模型适用于中国荷斯坦牛乳脂率变化的曲线拟合。