Establishment of physicochemical measurements of water polluting substances via flow perturbation gas chromatography

Spillage of water polluting substances via industrial disaster may cause pollution to our environment. Thus, reversed-flow gas chromatography (RF-GC) technique, which applies flow perturbation gas chromatography, was used to investigate the evaporation and estimate the diffusion coefficients of liquid pollutants. Selected alcohols (99.9% purity) and its mixtures were used as samples. The evaporating liquids (stationary phase) were carried out by carrier gas-nitrogen, 99.9% purity (mobile phase) to the detector. The findings of this work showed the physicochemical measurements may vary depending on the composition of water and alcohol mixtures, temperature of the mixtures, as well as the types of alcohol used. This study implies that there is a variation in the results based on the concentration, types and temperature of the liquids that may contribute in the references for future research in the area of environmental pollution analysis

Perinatal mortality in the Cape Province, 1989 - 1991

No Abstract

Rotating bending fatigue behaviour and quasi-static tensile properties of Wire Arc Additively Manufactured 308L stainless steel

Wire Arc Additive Manufacturing (WAAM) is a direct energy deposition method used to manufacture steel components by using an electric arc as a heat source to melt a metal wire and deposit it layer by layer. In this study, monotonic tensile tests, standardized Charpy impact tests, and rotating bending fatigue tests are executed to characterize the mechanical properties of WAAM 308L stainless steel using specimens extracted from additively manufactured plates. In particular, monotonic tensile properties are investigated in three directions: that is 0, 90, and 45 degrees with respect to the plane of deposition, whereas the fatigue strength is quantified for one direction only, i.e. 90 degrees since this is deemed to be the weakest.The mechanical characterization highlights that WAAM 308L SS shows an anisotropic behaviour, an enhanced strain-rate sensitivity, and an overall reduced yield strength as compared to the base material 308L. The anisotropic material behaviour is explained by the microstructure morphology since the austenite grains form anisotropic columnar zones due to an uneven heat profile during production. During the fatigue tests, the relatively high strain rate sensitivity causes susceptibility to self-heating at relatively low loading frequencies, i.e. below 100Hz

GENOMIC AND TRANSCRIPTOMIC APPROACHES TOWARDS THE GENETIC IMPROVEMENT OF AN UNDERUTILISED CROPS: THE CASE OF BAMBARA GROUNDNUT

With the world population estimated to be nine billion by 2050, the need to exploit plant genetic diversity in order to increase and diversify global food supply, and minimise the over-reliance for food on a few staple crops is of the utmost importance. Bambara groundnut ( Vigna subterranea (L) Verdc.), is underutilised legume indigenous to Africa, rich in carbohydrates, with reasonable amounts of protein. It is known to be drought tolerant, able to grow on marginal lands where other major crops cannot with minimal rainfall (<700 mm) and chemical inputs. Crop improvement for abiotic stress tolerance and increasing/stabilising yield have been difficult to achieve due to the complex nature of these stresses, and the genotype x environment interaction (GxE). This review paper highlights how a number of recent technologies and approaches used for major crop research, can be translated into use in research of minor crops, using bambara groundnut as an exemplar species. Using drought tolerance as a trait of interest in this crop, we will demonstrate how limitations can affect genomic approaches for understanding traits in bambara groundnut, and, how genomic and transcriptomic methodologies developed for major crops can be applied to underutilised crops for better understanding of the genetics governing important agronomic traits. Furthermore, such approaches will allow for cross species comparison between major and minor crops, exemplified by bambara groundnut leading to improved research in such crops. This will lead to a better understanding of the role of stress-responsive genes and drought adaptation in this underutilised legume.Avec la population mondiale estim\ue9e \ue0 neuf milliards de personnes \ue0 \ue9ch\ue9ance 2050, il est imp\ue9rieux d\u2019exploiter la diversit\ue9 g\ue9n\ue9tique des plantes afin d\u2019accro\ueetre et diversifier la production globale en aliments, mais aussi r\ue9duire la d\ue9pendance \ue0 outrance de peu d\u2019 aliments de base pour l\u2019alimentation humaine. Le vouandzou ( Vigna subterranea (L) Verdc.), est une l\ue9gumineuse indig\ue8ne sous utilis\ue9e enAfrique, mais qui est riche en amidon, avec une quantit\ue9 raisonnable de proteine. Il reconnu comme \ue9tant resistant \ue0 la s\ue9cheresse, il est capable de pousser et de r\ue9aliser un cycle v\ue9g\ue9tatif et reproducteur parfait dans les zones marginales de basse pluiviom\ue9trie (<700 mm) o\uf9 d\u2019autres cultures majeures ne peuvent survivre. L\u2019am\ue9lioration des cultures pour la tol\ue9rance face aux stress abiotiques et l\u2019accroissement et la stabilization des rendements ont \ue9t\ue9 difficiles \ue0 r\ue9aliser en raison de nature complexe de ces stress et l\u2019influence de l\u2019interaction genotype-environment (GxE). Cette revue de literature montre comment les nombreuses technologies et approaches r\ue9centes utilis\ue9es par la recherche sur les cultures majeures peuvent adapt\ue9es et utilis\ue9es dans la recherhe sur les cultures mineures, en se servant du bambara groundnut comme esp\ue8ce mod\ue8le. En prenant la tolerance \ue0 la s\ue9cheresse comme caract\ue8re d\ue9sir\ue9 pour cette culture, nous allons d\ue9montrer commnents les insuffisances des approches de g\ue9nomique peuvent emp\ueacher la ma\ueetrise des caract\ue8res d\ue9sir\ue9s chez le vouandzou et comment les techniques de g\ue9nomique et de transcriptomique d\ue9velopp\ue9es pour les cultures majeures peuvent \ueatre appliqu\ue9es aux cultures sous utilis\ue9es afin de mieux comprendre les d\ue9terminants g\ue9n\ue9tiques gouvernant les caract\ue8res agronomiques. De plus, de telles approaches permettra de comparer les cultures majeures et mineures, avec ici l\u2019exemple du vouandzou qui permettra d\u2019am\ue9liorer le niveau de recherche chez de telles cultures. Cela permettra de mieux comprendre le r\uf4le des genes r\ue9pondant au stress hydrique et l\u2019adaptation \ue0 la s\ue9cheresse chez cette l\ue9gumineuse sous utilis\ue9e

Impact of Nitrogen Regimes and Planting Densities on Stem Physiology, Lignin Biosynthesis and Grain Yield in Relation to Lodging Resistance in Winter Wheat (Triticum aestivum L.)

Higher plant population and nitrogen management is an adopted approach for improving crop productivity from limited land resources. Moreover, higher plant density and nitrogen regimes may increase the risk of stalk lodging, which is a consequence of complex interplant competition of individual organs. Here, we aimed to investigate the dynamic change in morphology, chemical compositions and lignin promoting enzymes of the second basal inter-nodes altering lodging risk controlled by planting density and nitrogen levels. A field trial was conducted at the Mengcheng research station (33°9′44″N, 116°32′56″E), Huaibei plain, Anhui province, China. A randomized complete block design was adopted, in which four plant densities, i.e., 180, 240, 300, and 360 × 104 ha−1 and four N levels, i.e., 0, 180, 240, and 300 kg ha−1 were studied. The two popular wheat varieties AnNong0711 and YanNong19 were cultivated. Results revealed that the culm lodging resistance (CLRI) index of the second basal internodes was positively and significantly correlated with light interception, lignin and cellulose content. The lignin and cellulose contents were significantly and positive correlated to light interception. The increased planting density and nitrogen levels declined the lignin and its related enzymes activities. The variety AnNong0711 showed more resistive response to lodging compared to YanNong19. Overall our study found that increased planting densities and nitrogen regimes resulted in poor physical strength and enzymatic activity which enhanced lodging risk in wheat varieties. The current study demonstrated that stem bending strength of the basal internode was significantly positive correlated to grains per spike. The thousand grain weight and grain yield had a positive and significant relationship with stem bending strength of the basal internode. The results suggested that the variety YanNong19 produces higher grain yield (9298 kg ha−1) at density 240 × 104 plants ha−1, and 180 kg ha−1 nitrogen, while AnNong0711 produced higher grain yield (10178.86 kg ha−1) at density 240 × 104 plants ha−1 and with 240 kg ha−1 nitrogen. Moreover, this combination of nitrogen and planting density enhanced the grain yield with better lodging resistance

Sub clinical vitamin A deficiency and anemia among Vietnamese children less than five years of age

The objective of the study was to assess the prevalence of sub clinical vitamin A deficiency and anemia in Vietnamese children. For this, a cross-sectional survey was conducted in 40 villages (clus-ters) of four ecological regions in Vietnam during Apr-May 2001. In total 1657 children less than 5 years old were included by a cluster random sampling method. The prevalence of sub clinical vita-min A deficiency (serum retino

New di-ferrocenyl-ethynylpyridinyl triphenylphosphine copper halide complexes and related di-ferricenyl electro-crystallized materials

Three di-ferrocenyl-ethynylpyridinyl copper complexes have been synthesised and CV measurements made.</p

Effective interaction between helical bio-molecules

The effective interaction between two parallel strands of helical bio-molecules, such as deoxyribose nucleic acids (DNA), is calculated using computer simulations of the "primitive" model of electrolytes. In particular we study a simple model for B-DNA incorporating explicitly its charge pattern as a double-helix structure. The effective force and the effective torque exerted onto the molecules depend on the central distance and on the relative orientation. The contributions of nonlinear screening by monovalent counterions to these forces and torques are analyzed and calculated for different salt concentrations. As a result, we find that the sign of the force depends sensitively on the relative orientation. For intermolecular distances smaller than $6\AA$ it can be both attractive and repulsive. Furthermore we report a nonmonotonic behaviour of the effective force for increasing salt concentration. Both features cannot be described within linear screening theories. For large distances, on the other hand, the results agree with linear screening theories provided the charge of the bio-molecules is suitably renormalized.Comment: 18 pages, 18 figures included in text, 100 bibliog