Response of rainfed bread and durum wheat to source,level and timing of nitrogen fertilizer on two Ethiopian Vertisols: II. N uptake,recovery and efficiency

In trials conducted at 2 highland Vertisol sites in Ethiopia in 1990 and 1991, 2 locally popular wheat cultivars, 1 spring bread wheat (Triticum aestivum L.) and 1 durum wheat (T. durum Desf.), were supplied with nitrogen (N) fertilizer at 0, 60 and 120 kg N ha^–1 in the form of large granular urea (LGU), standard urea prills or ammonium sulfate. N was applied all at sowing, all at mid-tillering or split-applied between these two stages (1/3:2/3). While durum wheat exhibited the highest N concentration in grain and straw, bread wheat, because of its higher productivity, resulted in a greater grain and total N uptake. In general, split application of N and use of LGU as N source enhanced grain and total N uptake, apparent N recovery and agronomic efficiency of N, particularly under severe water-logging stress. Where significant, the interactions among the experimental factors substantiated the superior responsiveness of the bread wheat cultivar to fertilizer N, and the beneficial effects of split N application and LGU as an N source. Split application of N tended to nullify the positive effects of LGU, presumably by approximating the delayed release of N achieved with LGU. Considering the potential benefits to Ethiopian peasant farmers and consumers, split application of N should be advocated, particularly on water-logged Vertisols; LGU could be an advantageous N source assuming a cost comparable to the conventional N source urea.     

Pleiotropic,Unique and Shared Responses Elicited by IL-6 Family Cytokines in Human Vascular Endothelial Cells

Vascular endothelial cells express glycoprotein 130 (gp130), which is utilized as a signaling receptor by cytokines in the interleukin-6 (IL-6) family. Several IL-6 family cytokines can be found in the circulatory system during physiological or pathological conditions, and may influence endothelial function and response. This study evaluated and compared the cellular and molecular responses induced by IL-6 family cytokines in human endothelial cells. A proteomic analysis showed that IL-6 family cytokines induce the release of a range of proteins from endothelial cells, such as C-C motif chemokine ligand 23, hepatocyte growth factor, and IL-6. Pathway analysis indicated that gp130-signaling in endothelial cells regulates several functions related to angiogenesis and immune cell recruitment. The present investigation also disclosed differences and similarities between different IL-6 family cytokines in their ability to induce protein release and regulate gene expression and intracellular signaling, in regards to which oncostatin M showed the most pronounced effect. Further, this study showed that soluble gp130 preferentially blocks trans-signaling-induced responses, but does not affect responses induced by classic signaling. In conclusion, IL-6 family cytokines induce both specific and overlapping molecular responses in endothelial cells, and regulate genes and proteins involved in angiogenesis and immune cell recruitment.     

Tubular shaped composites made from polythiophene covalently linked to Prato functionalized N-doped carbon nanotubes

A simple methodology to produce tubular nitrogen-doped carbon nanotube/polythiophene covalently linked composites is described. Nitrogen doped carbon nanotubes (N-CNTs) were made by the floating catalyst CVD method using toluene, ferrocene and tetramethylethylenediamine (TMEDA) as reagents. Functionalization of the N-CNTs was achieved using 3-thiophenecarboxaldehyde and N-methylglycine in 1,2-dichlorobenzene (Prato reaction). Elemental analysis showed nitrogen incorporation of N into the N-CNTs (1.8%) and also the N-methylglycine functionalized N-CNTs (f-N-CNTs; 6.2%). A series of f-N-CNT/thiophene monomer mixtures (weight ratios 1:3, 1:10 and 1:20) were used to make f-N-CNT/polythiophene tubular composites. As the amount of thiophene monomer was increased, the overall diameter of the polymer layer attached onto the N-CNTs increased. Polymer thickness also varied with reaction time (1 h, 12 h and 24 h). The combination of acid functionalization and N–doping gives the best coverage of the CNTs by polythiophene, in which the polythiophene preferentially binds to the f-N-CNTs to give tubular structures.     

Accumulation of chylomicron remnants in homozygous subjects with familial hypercholesterolaemia

Despite the obvious differences between the USA and UK health care systems, they share the characteristics of being motivated and managed in relation to cost and process rather than quality (the improved health status of patients). Whilst governments and insurers across the world use the rhetoric of quality, they, as epitomized by the behaviours of UK and USA decision makers, fail to define, measure and implement quality outcome policies. These behaviours are examined and some of their causes are explored briefly. Competition, as designed and used in public (e.g. UK National Health Service) and private (e.g. USA managed care) markets is shown to fail both to identify quality outcome targets and to provide evidence-based and efficient mechanisms to motivate decision makers to be orientated towards continuous quality outcome improvement in health care. A central policy challenge is, consequently, not just the measurement of quality outcomes but also their management into practice.     

Ring-opening Metathesis Co-polymerization of a C60-cyclopentadiene Cycloadduct and Norbornene with the Grubbs Second-generation Catalyst

A series of C₆₀-containing polymers were synthesized by the co-polymerization of a C₆₀-cyclopentadiene cycloadduct and norbornene in varying ratios. The polymerization was facilitated by a catalytic amount of Grubbs second generation catalyst and the co-polymers formed were investigated by spectroscopic and thermal techniques.     

Multi‐criteria decision evaluation in groundwater zones identification in Moyale‐Teltele subbasin,South Ethiopia

The conventional approaches such as ground‐based surveys and exploratory drilling for groundwater investigation are time‐consuming and uneconomical. Systematic organisation of data of characteristics of any terrain, evaluation of inter‐thematic, interclass dependencies and variability, and also analysing cumulative effect on the development of groundwater regime is the best approach which the current decade requires. This is proved by generation of the thematic information on the above factors through remote sensing technique, and integration in geographic information system (GIS) for evaluation using multi‐criteria decision‐making techniques. This paper presents the results of the attempt made to identify the groundwater potential zones in the Moyale‐Teltele Sub basin of the Genale Dawa River Basin in South Ethiopia using the integrated approaches of remote sensing and geographic information systems. Six geologic, physiographic, and hydrologic factors were applied namely: lithology, structure, geomorphology, slope, land cover, and drainage. Weighted Overlay Analysis using multicriteria decision technique is implemented to produce the groundwater potential map of the area. This result is further verified by groundwater yield data of boreholes and springs collected in the field and from previous reports. The validation revealed that the result is in good conformity with the actual yield of the wells and springs.     

用于三电平逆变器的IGBT提高DC／AC转换的效率

当我们谈论效率时，我们主要指的是电力效率。然而，这种用法并不是效率一次本身的完整含义。在电力电子应用巾，工程师在开发新产品过程中的追求的主要目标是以最大限度地发挥不同类型的效率，如电效率和热效率，以及优化谐波失真和产品整体的尺寸。