Sap flow measurements with some thermodynamic methods,flow integration within trees and scaling up from sample trees to entire forest stands

Sap flow measurement techniques and evaluation of data are reviewed. Particular attention is paid to the trunk segment heat balance (THB) and heat field deformation (HFD) methods based on 30 years experience. Further elaboration of sap flow data is discussed in terms of integrating flow for whole stems from individual measuring points, considering variation of radial patterns in sapwood and variation around stems. Scaling up of data from sets of sample trees to entire forest stands based on widely available biometric data (partially on remote sensing images) is described and evaluated with a discussion of the magnitude of errors, the routine procedure applicable in any forest stand and practical examples.     

Diffusion ordered spectroscopy as a complement to size exclusion chromatography in oligosaccharide analysis

A series of N-acetyl-chitooligosaccharides (GlcNAc)(1-6) have been studied by a nuclear magnetic resonance (NMR) method, diffusion ordered spectroscopy (DOSY). DOSY has also been applied to two additional synthetic related oligosaccharides [GlcNH(2)-(GlcNAc)(4) and GlcNH(2)-(GlcNAc)(2)-GlcNAcSO(3)Na]. A plot of the log of the determined diffusion coefficients (logD) of (GlcNAc)(n) versus the log of molecular weight was linear (6 points, R(2) = 0.995). The molecular weights of the two synthetic chitin derivatives could be estimated to within 10% error. The processed NMR data of all the chitooligosaccharides was also plotted in a polyacrylamide gel-like format to aid visual interpretation. Moreover, the logD value of the NMR signal resonances of a chitin-binding protein (hevein) changed as a function of a given titrated ligand, (GlcNAc)(6). Evidence for a 2:1 hevein:(GlcNAc)(6) complex is detected by DOSY at high hevein:(GlcNAc)(6) ratios. This data is consistent with published analytical ultracentrifugation and isothermal titration calorimetry data. A 1:1 complex is preferred at higher ligand concentrations. DOSY can complement size exclusion chromatography in carbohydrate research with the advantage that oligosaccharides are more readily detected by NMR.     

Proteome analysis of human colon cancer by two-dimensional difference gel electrophoresis and mass spectrometry

Two-dimensional difference gel electrophoresis (2-D DIGE) coupled with mass spectrometry (MS) was used to investigate tumor-specific changes in the proteome of human colorectal cancers and adjacent normal mucosa. For each of six patients with different stages of colon cancer, Cy5-labeled proteins isolated from tumor tissue were combined with Cy3-labeled proteins isolated from neighboring normal mucosa and separated on the same 2-D gel along with a Cy2-labeled mixture of all 12 normal/tumor samples as an internal standard. Over 1500 protein spot-features were analyzed in each paired normal/tumor comparison, and using DIGE technology with the mixed-sample internal standard, statistically significant quantitative comparisons of each protein abundance change could be made across multiple samples simultaneously without interference due to gel-to-gel variation. Matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) and tandem (TOF/TOF) MS provided sensitive and accurate mass spectral data for database interrogation, resulting in the identification of 52 unique proteins (including redundancies due to proteolysis and post-translationally modified isoforms) that were changing in abundance across the cohort. Without the benefit of the Cy2-labeled 12 sample mixture internal standard, 42 of these proteins would have been overlooked due to the large degree of variation inherent between normal and tumor samples.     

玉米种质资源抗弯孢菌叶斑病特性研究

针对近年弯孢菌叶斑病日益严重的发生趋势,对1698份玉米种质(自交系、群体、杂交种以及特殊材料)进行了抗弯孢菌叶斑病鉴定.结果表明,中国玉米种质抗性较引进种质抗性好;不同省份所供种质抗性存在差异,北京、四川、广西种质总体抗性较好;在新选育的自交系中,鉴定出12份高抗材料;在当前培育的杂交种中,有22份高抗或抗弯孢菌叶斑病;玉米对弯孢菌叶斑病抗性在相同核基因、不同细胞质种质间无差异;玉米抗大斑病基因对抗弯孢菌叶斑病无效.     

我国部分小麦种质资源主要品质性状鉴定评价

"九五"期间,测定了来自10省(市、自治区)的1589份小麦种质资源的主要品质性状,了解了其籽粒的硬度、沉降值和蛋白质含量状况.筛选出一批高蛋白质、高硬度、高沉降值的优质资源,为小麦生产和品质育种提供种质基础.     

Bequest: The framework and directory of assessment methods

This paper has outlined the areas of the Environment and Climate Programme (Economic and Social Aspects of Human Settlement) the BEQUEST project addresses. It has also examined the framework for analysis the project sets out for a common understanding of SUD and the assessment methods currently made use of by planners, architects, engineers and surveyors to build environmental capacity. The paper has done this by:

No effects of pulsed radio frequency electromagnetic fields on melatonin, cortisol, and selected markers of the immune system in man

There is growing public concern that radio frequency electromagnetic fields may have adverse biological effects. In the present study eight healthy male students were tested to see whether or not radio frequency electromagnetic fields as used in modern digital wireless telecommunication (GSM standard) have noticeable effects on salivary melatonin, cortisol, neopterin, and immunoglobulin A (sIgA) levels during and several hours after exposure. In a specifically designed, shielded experimental chamber, the circularly polarized electromagnetic field applied was transmitted by an antenna positioned 10 cm behind the head of upright sitting test persons. The carrier frequency of 900 MHz was pulsed with 217 Hz (average power flux density 1 W/m2). In double blind trials, each test person underwent a total of 20 randomly allotted 4 hour periods of exposure and sham exposure, equally distributed at day and night. The results obtained show that the salivary concentrations of melatonin, cortisol, neopterin and sIgA did not differ significantly between exposure and sham exposure.     

Neospora caninum:Tachyzoites Express a Potent Type-I Nucleoside Triphosphate Hydrolase,but Lack Nucleoside Diphosphate Hydrolase Activity

Asai, T., Howe, D. K., Nakajima, K., Nozaki, T., Takeuchi, T., and Sibley, L. D.Neospora caninum: Tachyzoites Express Type-I Nucleoside Triphosphate Hydrolase1. But Lack Nucleoside Diphosphate Hydrolase Activity.Experimental Parasitology90,277–285. We have identified type I nucleoside triphosphate hydrolase (NTPase; EC 3.6.1.3) activity, previously thought to be restricted to the virulent strains ofToxoplasma gondii, in the cell extracts ofNeospora caninumtachyzoites. Sequence analysis of a complete cDNA from Nc-1 strain indicated thatN. caninumNTPases shared approximately 69% identity to the NTPases ofT. gondiiand are most similar to the NTPase-I isozyme. Southern blot analysis of genomic DNA and sequence analysis of two independentNTPclones from the Nc-1 strain revealed the presence of multiple genes, at least two of which are transcribed. Substrate specificity andK_mvalues for MgATP²⁻and MgADP⁻hydrolysis for recombinant or partially purified native NcNTPase were the same as those for the type I isozyme (NTPase-I). Significantly, no type II enzyme (NTPase-II) activity for NDP hydrolysis was detected in cell extracts ofN. caninum, although it is universally present in allT. gondiistrains that have been tested. This intriguing difference between these two closely related apicomplexan parasites may provide insight into the function of the NTPases during intracellular parasitism.     

应用人工神经网络评价湖泊的富营养化

应用人工神经网络方法,以化学需氧量、总氮、总磷和透明度作为评价参数,经反复尝试,构建了具有４层结构用于评价湖泊富营养化的误差逆传播网络．其输入层有４个神经元,２个隐含层也各有４个神经元,输出层有１个神经元．以太湖富营养化评价标准作为样本模式提供给网络,按照误差逆传播网络的学习规则对网络进行训练,经过３７６８４次学习后,网络达到预先给定的收敛标准．使网络具备了识别湖泊富营养化程度的功能．应用该网络对我国１７个湖泊的富营养化程度进行评价,操作过程简便易行,评价结果切合实际,展示了这种方法的一系列优点．     

A new method for the improvement of data production in phytochemical analysis

Introduction – The use of the average analytical signal for the construction of curves by the least squares method (LSM) over the standard addition method (SAM) is widespread. It would be advantageous, however, to find a way to avoid intermediary averages, which are known to be the cause of significant increases in standard deviations (SD). Objective – To develop a protocol that uses all gathered data to create curves by LSM over SAM. To use Excel^® for the estimation of y = mx + b and R² rather than using LSM equations for the SD of m, x and b. Methodology – The level of lead (II) in the bark (cork) of Quercus suber Linnaeus was determined using differential pulse anodic stripping voltammetry (DPASV). Three current samples were taken for each of the four standard additions. These signals were combined for adjustment by LSM. The results were compared with those obtained after averaging the current for each addition, and the expression of uncertainty in the measurements determined. Results – The new method shows an expanded uncertainty of ± 0.3321 μg/g (nearly 1.42%). The difference between the results obtained by the new and the old method is 0.01 μg/g (23.41 and 23.40 μg/g). The limit of detection changed approximately from 4.8 to 4 μg/g and the relative SD approximately from 9 to 6%. Conclusion – The absence of intermediary averages in curves improved the determination of lead (II) in cork by DPASV. Estimation of SD only with LSM equations produced results that were significantly worse. The changes are large enough to transform an apparently internally non‐validated procedure (repeatability for precision) into an internally validated procedure. Copyright © 2009 John Wiley & Sons, Ltd.