优选发酵毕赤酵母与酿酒酵母混合发酵增香酿造爱格丽干白葡萄酒

【目的】研究优选发酵毕赤酵母（Pichia fermentans）与酿酒酵母（Saccharomyces cerevisiae）混合发酵对‘爱格丽’（Ecolly）干白葡萄酒的增香作用,优化干白葡萄酒的酿造工艺。【方法】将发酵毕赤酵母菌株H5Y-28与酿酒酵母菌株F5以10﹕1、4﹕1、1﹕1、1﹕4、1﹕10比例接种,进行模拟葡萄汁的混合发酵,并以酿酒酵母纯发酵为对照,发酵过程中监测酵母的活菌数、总菌数,建立菌体生长动力学模型。按相同接种比例进行爱格丽干白葡萄酒的发酵应用,以酿酒酵母纯发酵和添加发酵毕赤酵母胞外酶处理作为对照,酿造次年4月,对所酿葡萄酒酒样进行香气的感官分析和GC-MS分析。【结果】菌体生长动力学表明,随着发酵毕赤酵母接种比例的升高,其存活数量和存活时间明显增加,但优选菌株H5Y-28的高比例（10﹕1、4﹕1）接种处理会降低酿酒酵母的最大生长数量。感官分析结果表明,混合发酵有利于增强‘爱格丽’葡萄酒的果香和花香,尤其是热带水果香气,但高发酵毕赤酵母接种比例（10﹕1）会给葡萄酒带来较强的生青味,而酒样1﹕1、4﹕1仅引入较弱的生青味。挥发性香气成分分析结果表明,品种香气成分的含量随着发酵毕赤酵母接种比例的升高而增加,尤其是萜烯类和C13-去甲类异戊二烯化合物。此外,添加胞外酶能显著提高葡萄酒品种香气的含量,尤其是C13-去甲类异戊二烯化合物的含量（高于纯酿酒酵母发酵酒样90%）。混合发酵显著增加了酒样中发酵香气中的乙酸酯、C6-C12脂肪酸及其酯类、异戊醇与苯乙醇的含量。与单一酿酒酵母发酵酒样相比,1﹕1接种比例有助于提高酒样中26%品种香气成分和39%发酵香气成分的含量,尤其是显著地提高了中链脂肪酸乙酯的含量（40%）。【结论】毕赤酵母与酿酒酵母1﹕1接种处理不影响酿酒酵母生长,且具有较强的增香酿造潜力。     

EFFECTS OF FASTING AND INTRALUMINAL CONTRAST ENHANCEMENT ON ULTRASONOGRAPHIC APPEARANCE OF THE EQUINE SMALL INTESTINE

The equine small intestine is challenging to evaluate ultrasonographically. In humans, hydrosonography has been used to improve ultrasonographic images of the small intestine. We hypothesized that fasting horses for 24 h would enhance the ability to image the small intestine transabdominally by separating intestinal loops and reducing intraluminal gas, and that the administration of intragastric contrast agent would further improve that ability. Ten healthy horses were examined ultrasonographically under three treatment conditions: (a) regular diet, (b) after a 24‐h fast, and (c) fasted plus intragastric administration of water and mineral oil. During each phase of the study, 30‐s video clips were obtained from four predetermined abdominal windows, and were examined to determine diagnostic quality. Fasting improved the ability to obtain high‐quality images of the small intestine significantly. The addition of contrast agent resulted in qualitative improvement in image quality, but differences did not result in statistically significant improvement.     

脑心肌炎增强型绿色荧光蛋白嵌合病毒的构建

携带增强型绿色荧光蛋白(Enhanced green fluorescent protein, EGFP)的脑心肌炎(Encephalomyocarditis virus, EMCV)嵌合病毒是研究该病毒体内外生物学特性的有力工具。因此,本研究基于前期构建的巨细胞病毒(Cytomegalovirus, CMV)感染性克隆,在EMCV基因组2A蛋白序列之后插入EGFP基因片段,并将重组质粒转染BHK-21细胞,获得携带EGFP的嵌合病毒。通过荧光定量PCR(real-time PCR)、间接免疫荧光(Indirect immunofluorescence assay, IFA)及半数组织细胞感染量测定(Median tissue culture infective dose, TCID₅₀)等方法对拯救病毒的基因组复制、蛋白表达及病毒粒子的感染性进行测定,结果证实嵌合病毒能够在BHK-21细胞上成功表达EGFP并产生完整的病毒粒子。然而,相较于野生型亲本拯救病毒,嵌合病毒在BHK-21细胞上的复制能力降低,并且在连续传代后逐渐失去绿色荧光信号,表明嵌合病毒中EGFP...     

基于营养通道模型的海州湾中国明对虾生态容纳量

通过增殖放流,增加优质渔业资源、改善种群结构是渔业资源养护的重要手段,而增殖生态容量的研究是科学实施增殖放流的前提。为确定海州湾中国明对虾的生态容纳量,根据2013年连云港海州湾渔业生态修复水域的调查资料,应用Ecopath with Ecosim(EwE)软件中的Ecopath模块,构建了该区域的生态系统能量流动简易模型,计算了放流种类中国明对虾的增殖生态容纳量。结果表明:系统各功能组营养级范围在1~4.42。系统总流量9335.191 t·km~(–2)·a~(–1),系统总初级生产力3892.630 t·km~(–2)·a~(–1),系统初级生产力与总呼吸量的比值为1.331,连接指数为0.415,杂食指数为0.174,Finn循环指数为11.4%,平均能流路径为2.8系统尚处于由衰竭状态向恢复状态转变,还未恢复到成熟态。中国明对虾不是本海域的关键种,当前中国明对虾的生物量为0.04 t·km–2·a–1,中国明对虾的生态容纳量为0.846 t·km~(–2)·a~(–1)。     

长丝裂腹鱼全人工繁殖试验

对野外采捕内塘人工驯养成熟的长丝裂腹鱼开展人工繁殖试验,为长丝裂腹鱼养殖及增殖放流奠定基础。2008年在金沙江丽江境内采集到32尾50~500 g长丝裂腹鱼,在大理州裂腹鱼原种场经过7年驯养。2015年4月7日催产雌鱼15尾(均重3 000 g)、雄鱼9尾(均重1 500 g),亲鱼在50 mg/L MS-222溶液中麻醉后注射鲤脑下垂体和绒毛膜促性腺激素混合溶液。效应时间48 h 20 min;6尾雌鱼产卵,获得鱼卵64 790粒,催产率40%;受精卵23 350粒,受精率36%;获得鱼苗10 675尾,出苗率45.7%。     

秋水仙素诱导获得5个木薯品种的同源四倍体植株

为获得纯合稳定的木薯（Manihot esculenta Crantz）同源四倍体,以不同质量浓度（0.1、0.3、0.5 g/L）的秋水仙素和时间（3、6、9 h）组合对5个木薯品种的腋芽进行诱导处理,然后转入MS培养基培养再生试管苗,采用流式细胞仪和根尖压片技术鉴定其倍性,筛选出四倍体。经多代无性繁殖,结果显示5个品种均获得稳定的四倍体植株。将木薯Col22和华南8号的四倍体移入温室,5个月后与对照二倍体相比,其叶片变宽、变厚,气孔的长度、宽度、密度等方面均有显著差异。同源四倍体新种质的创制为进一步用于木薯品种改良提供了珍贵的试材。     

镂空方型增殖礁上升流特性的粒子图像测速试验

利用粒子图像测速技术（particle image velocimetry）对镂空方型增殖礁单体礁和组合礁的上升流流场特性进行分析,按照海区实测流速和礁区选址要求,设定5个不同的来流速度0.2、0.4、0.6、0.8、1.0 m/s,并计算出试验流速分别为0.045、0.090、0.135、0.180、0.225 m/s。结果表明：单体礁在任何一种迎流方式下,上升流的规模都随来流速度的增加而增大;而相同来流速度下,主视面90o迎流时,上升流规模最大;单体俯视面45o迎流时,上升流规模最小;礁体横向组合排列时,礁体间距在0.5L～1.0 L时所产生的上升流规模最大,礁体间的协同作用最强;礁体纵向组合排列时,在0.5L～1.5 L倍的间距时,礁体间的相互作用较强,形成的上升流规模最大。     

一种增强波导多层光盘跟踪信号的方法

波导多层光盘存储系统是基于新原理的存储系统。基于该原理,提出了波导多层光盘的设计思路。自动聚焦和信道跟踪信号是光盘驱动器中的关键信号,用来纠正光盘在旋转中产生的跳动、偏心等误差。针对波导多层光盘的特点,提出了跟踪信号增强的方法,该方法通过控制光盘内层信息面的反射率来提高聚焦和信道跟踪信号的强度。分析结果表明,该方法可以显著提高跟踪信号的平均强度,解决波导多层光盘技术中聚焦寻迹信号微弱的问题。     

Light‐induced reduction of FE3+ as related to causes of chlorosis in cotton

In growth chambers, cotton (Gossypium hirsutum L. genetic selection ‘M8') was grown in a synthetic growth medium under four light regimes: low pressure sodium (LPS), LPS + Incandescent (Inc), cool white fluorescent (CWF) and CWF + Inc lamps at 22 C under LPS lamps. Less chlorosis developed at 26 C than at 22 C and less under LPS + Inc than under LPS lamps. All plants were green under CWF and CWF + Inc light. Green and chlorotic plant tissue contained about the same concentrations of Fe. The proposed hypothesis was that chlorotic tissue’ contained less Fe²⁺ than green tissue. Chlorotic leaves treated with FeSO₄ turned a green color. Enough CWF + Inc light passed through an intact leaf to reduce Fe³⁺ to Fe²⁺ in vitro. Also in vitro, Fe³⁺ was reduced by CWF, by Inc, but not by LPS light. The amount of Fe³⁺ reduced during an illumination period was directly proportional to the quantity of light used. In vitro, citrate and malate enhanced Fe³⁺ reduction, whereas phosphate, pyrophosphate, OH^‐, Cu²⁺, Ni²⁺, Mn²⁺, Zn²⁺, and F^‐ all inhibited Fe³⁺ reduction by light. Orthophosphate was about 8 times as effective as organic P in decreasing Fe³⁺ reduction. Citrate largely alleviated the inhibitory effects of Pi and pH (up to pH 6). The data also provide a possible explanation of a role for many of the elements known to induce or aggravate Fe chlorosis (inhibit Fe³⁺ reduction). Quantity and quality of light apparently play key roles in plant growth as related to reduction of Fe³⁺ to Fe²⁺ in plant tops.     

农家书屋与农民素质提高刍议

阐述了提高农民素质的重要性,分析目前我国农民素质中普遍存在的文化素质、科技素质、思想道德素质偏低的现状,指出了农家书屋在提高农民素质中所具有的资源、教育等优势,探讨农家书屋为提高农民素质服务的途径.