Long-Range Correlations of Global Sea Surface Temperature

Scaling behaviors of the global monthly sea surface temperature (SST) derived from 1870–2009 average monthly data sets of Hadley Centre Sea Ice and SST (HadISST) are investigated employing detrended fluctuation analysis (DFA). The global SST fluctuations are found to be strong positively long-range correlated at all pertinent time-intervals. The value of scaling exponent is larger in the tropics than those in the intermediate latitudes of the northern and southern hemispheres. DFA leads to the scaling exponent α = 0.87 over the globe (60°S~60°N), northern hemisphere (0°N~60°N), and southern hemisphere (0°S~60°S), α = 0.84 over the intermediate latitude of southern hemisphere (30°S~60°S), α = 0.81 over the intermediate latitude of northern hemisphere (30°N~60°N) and α = 0.90 over the tropics 30°S~30°N [fluctuation F(s) ~ s^α], which the fluctuations of monthly SST anomaly display long-term correlated behaviors. Furthermore, the larger the standard deviation is, the smaller long-range correlations (LRCs) of SST in the corresponding regions, especially in three distinct upwelling areas. After the standard deviation is taken into account, an index χ = α * σ is introduced to obtain the spatial distributions of χ. There exists an obvious change of global SST in central east and northern Pacific and the northwest Atlantic. This may be as a clue on predictability of climate and ocean variabilities.     

辐照技术应用于茶叶上的研究进展

本文综述了国内外辐照处理对茶叶卫生质量、感官品质、内含物的影响以及农残降解的研究进展,展望了辐照技术在茶叶上的应用前景和发展方向,为辐照技术在茶叶上的产业化应用提供参考依据。     

Global Completeness of the Bat Fossil Record

Bats are unique among mammals in their use of powered flight and their widespread capacity for laryngeal echolocation. Understanding how and when these and other abilities evolved could be improved by examining the bat fossil record. However, the fossil record of bats is commonly believed to be very poor. Quantitative analyses of this record have rarely been attempted, so it has been difficult to gauge just how depauperate the bat fossil record really is. A crucial step in analyzing the quality of the fossil record is to be able to accurately estimate completeness. Measures of completeness of the fossil record have important consequences for our understanding of evolutionary rates and patterns among bats. In this study, we applied previously developed statistical methods of analyzing completeness to the bat fossil record. The main utility of these methods over others used to study completeness is their independence from phylogeny. This phylogenetic-independence is desirable, given the recent state of flux in the higher-level phylogenetic relationships of bats. All known fossil bat genera were tabulated at the geologic stage or sub-epoch level. This binning strategy allowed an estimate of the extinction rate for each bat genus per bin. Extinction rate—together with per-genus estimates of preservation probability and original temporal distributions—was used to calculate completeness. At the genus level, the bat fossil record is estimated to be 12% complete. Within the order, Pteropodidae is missing most of its fossil history, while Rhinolophoidea and Vespertilionoidea are missing the least. These results suggest that 88% of bats that existed never left a fossil record, and that the fossil record of bats is indeed poor. Much of the taxonomic and evolutionary history of bats has yet to be uncovered.     

籼稻品质分析的近红外光谱模型建立及其应用研究

为了满足籼稻品质快速分析的需求,本研究利用籼稻精米粉近红外光谱建立了直链淀粉含量、蛋白质含量、碱消值、垩白度的回归预测模型.结果表明,本研究提供的预测模型具有良好的测定效果,用偏最小二乘法(PLS)获得的籼稻精米粉直链淀粉含量、蛋白质含量、碱消值、垩白度的回归模型和交叉验证显示最优校正决定系数(R~2)和交叉检验均方误差(RMSECV)分别为0.9561、1.55,0.9510、0.258,0.9076、0.283,0.9014、4.14.说明所建的近红外光谱预测模型具有实用价值.     

A Method to Record the Surface Temperature Distribution of the Skin as a Safe and Ergonomic Approach to Diagnosis and Monitoring in Breast Cancer

Biophysics - Abstract—This article discusses the relevant results on early and safe detection of breast cancer with a thermal volume tomography (TVT) device produced in Russia. The device...     

褶合光谱分析法在农业科学分析中的应用

褶合光谱分析法是一种新的光谱信号分析法,刚刚开始应用于农业科学分析。本文详尽地介绍了它的产生,测定原理和在农业上适测领域,旨在推动此分析技术在农业上的应用。     

Phase-Locked Loop Technique to Record Resonance Frequency of Plant Tissue

An apparatus based on the phase-locked loop technique has been developed in order to record automatically the resonance frequency of a mechanically vibrating plant specimen. Hereby changes in the elasticity of the plant material can be continuously recorded. In order to demonstrate the use of the apparatus, elasticity changes of Avena coleoptiles due to exchange of the root medium were continuously recorded.     

晚期糖基化终末产物荧光光谱检测法在糖尿病筛查中的应用研究

主要研究人体皮肤晚期糖基化终末产物(Advanced glycation end products,AGE)荧光光谱的检测方法,并对AGE荧光光谱在糖尿病检测中的应用价值进行评估.利用研制的AGE荧光光谱检测装置,分别对73例受试者前臂内侧皮肤组织中AGE的荧光进行检测.同时,采用酶联免疫吸附法(ELISA)对受试者血...     

Phylogenomic Resolution of the Class Ophiuroidea Unlocks a Global Microfossil Record

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RNA干扰技术在植物线虫基因功能研究及虫害防治方面的应用

RNA干扰（RNA interference,RNAi）是双链RNA（double—stranded RNA,dsRNA）介导的同源mRNA特异降解的过程,具有高效性、非绝对特异性和表型可遗传性。其在遗传育种、基因功能研究、药物研发等各方面具有广泛的运用前景。近年已应用到植物线虫基因功能的研究中。随着对植物线虫基因组及基因功能研究的不断深入。RNAi技术在植物线虫防治方面的研究也取得了很大进展。     

利用主成分分析法分析乳腺癌术后患者的血清表面增强拉曼光谱

为了探寻一种利用血清光谱检测诊断乳腺癌术后复发转移的方法,研究分析了10例乳腺癌术后复发转移患者与10例乳腺癌术后复查正常患者的血清表面增强拉曼光谱特征。首先从两组血清表面增强拉曼光谱特征峰的位移与峰强的变化上进行比较,发现其分子结构发生变化,脂类的有序性,糖质环境都发生了改变。然后基于Matlab,采用主成分分析法（Principal Component Analysis,PCA）,对上述两组患者血清的表面增强拉曼光谱的13个指标进行分析,发现区分两组患者的效果可以达到95%左右。     

基于功率谱分析的基因编码序列单碱基突变研究

针对DNA序列单碱基的不同类型突变,利用数字信号处理方法,研究了单碱基替换突变、删除突变、插入突变对DNA序列三周期功率谱的影响。研究结果表明:对于不同长度的编码序列,替换突变对序列功率谱的影响较小,删除突变和插入突变对序列功率谱的影响较大;随着序列编码区长度的减小,替换、删除、插入突变对序列编码区的功率谱影响会越来越大。对于中等长度外显子,插入突变对序列三周期功率谱影响最大,对于短外显子,删除突变对序列三周期功率谱的影响最大。研究结果可为含突变基因编码区的识别与检测提供参考。     

荧光光谱分析法在地沟油鉴别中的应用研究

由于地沟油的成分含量复杂性和不定量性,导致了现有的单一检测方法不能同时满足快速和准确的辨认。荧光光谱具有高灵敏度和分辨率的特性,由此提出了一种利用荧光光谱快速检测食用油中是否掺有地沟油的新方法。将花生油分成7组,每组油所含的地沟油的比例不同,用220 nm到800 nm的激发和发射光检测各组样品油,收集其荧光数据后做归一化处理进行分析。在荧光实验中,特别是在365 nm和720 nm激发波长波段和434 nm发射波长波段,样品油的荧光强度与所含地沟油的体积分数大小明显成反比,当地沟油的体积分数大于5%时,荧光强度的衰减更为明显。结果证明了荧光光谱法检测地沟油的可行性,而且步骤更为简单。利用荧光光谱的非接触和高灵敏度的优势,能够更为简便地检测到加入了5%以上地沟油的花生油。     

信使RNA差异显示技术的最新进展

各种疾病,如肿瘤、遗传性疾病都是一种或多种基因异常表达的结果。寻找、定位疾病相关基因在目前分子生物学研究中占有十分重要的地位,Ｌｉａｎｇ等１９９２年首创了信使ＲＮＡ差异显示技术（ｍｅｓｓｅｎｇｅｒＲＮＡｄｉｆｆｅｒｅｎｔｉａｌｄｉｓｐｌａｙ,ｍＲＮＡ...     

Application of the Single-Dose Assay Technique to Psittacosis

When suspensions of psittacosis organisms were injected intracerebrally into groups of mice, a nearly linear relationship was observed between the concentration of the organisms injected and the mean time to death of the mice. Thirty-four psittacosis preparations were assayed and, by plotting the relationship between the reciprocal time to death for mice given the 10(-3) dilution of agent against the number of mouse intracerebral median lethal doses (MICLD(50)), a reference curve was established. By use of this reference curve, it was possible to estimate directly the LD(50) value of a psittacosis suspension of unknown concentration from the mean reciprocal time to death of a group of mice injected with a single dilution. By this procedure, the number of mice used was reduced by 62.5%, the titrations were completed in 3 to 5 days as compared with the usual 12 days, three to four times as many assays could be done in 1 day, and no assays had to be repeated. In addition, the precision of the single-dilution assay compared favorably with that of the LD(50) titration.     

图像反卷积复原技术在玉米45S rDNA转录图式研究中的运用

由于成像焦平面外杂光的干扰,宽场荧光显微镜所得的图像往往较模糊,使其不适合用来观察植物细胞核内的精细结构。该实验讨论了反卷积软件中对图像复原结果有较大影响的几个重要参数的设置。经过合适的图像反卷积复原,由宽场荧光显微镜获取的玉米45S rRNA原位杂交信号图像得以清楚显示。对所得杂交图像的分析表明:玉米45S rDNA转录往往先发生在核仁外围,且随着核仁转录活性的提高逐渐向核仁内部扩散,并最终与5S rRNA一起,在核仁内部的空洞结构中形成成熟rRNA。研究结果显示,反卷积复原可有效提高宽场荧光显微镜所得二维图像的分辨率,从而使宽场荧光显微镜在植物细胞核内精细结构研究中发挥更多的作用。