A CN-FDTD Scheme and Its Application to VLSI Interconnects/Substrate Modeling

In this paper, a two-dimensional (2D) Crank-Nicholason (CN) finite difference time domain (FDTD) method is proposed for VLSI interconnect/substrate characterization. Through rigorous truncation and dispersion error analyses, a guideline on using this technique is presented. Several iterative solvers are investigated to accelerate the solution of the CN-FDTD scheme. Numerical examples are given to demonstrate the accuracy and the efficiency of the proposed algorithm

Preparation of antibacterial microfibre

Three different kinds of antibacterial microfibres (270D, 300D and 330D) have been developed by adding 2-4 wt % nano silver masterbatch in the melt spinning process. The mechanical properties, silver content and morphology have been examined with tensile tester, inductively coupled plasma-optical emission spectrometer and scanning electron microscope respectively. Their antibacterial abilities are also studied with KS K 0693:2011. The results show that the added nano-particles have little influence on mechanical properties of antibacterial microfibres and their max strain and tenacity are similar to that of common manmade fibre. The fineness of the 270D, 300D and 330D samples are found to be 0.23, 0.26 and 0.30 den, and the corresponding added silver contents are 265.5, 231 and 259 ppm respectively. It is also observed that all samples bacteriostatic reduction rates are about 99.9% for both Staphylococcus aureus and Klebsiella pneumonia before washing. But after washing, it drops to 65.4%/75%, 91.9%/97.7% and 94.8%/99.9% respectively for both the bacteria in case of 270D, 300D and 330D samples. It is concluded that 300D and 330D microfibre samples have good antibacterial ability before and after washing

Numerical Modeling of Periodic Composite Media for Electromagnetic Shielding Application

This paper describes a methodology to extract effective electrical properties for periodic composite medium. The extraction algorithm is based on a periodic finite-difference time-domain (FDTD) method. The results are compared with conventional mixing theories and 3D Fourier series expansion methods. Two results show satisfactory agreement. With the extracted effective permittivity and conductivity, one can readily use these parameters to study electrical properties of composite materials with arbitrary micro-geometry and the shielding effects of using composite materials

Phosphorous fertilization alleviates drought effects on Alnus cremastogyne by regulating its antioxidant and osmotic potential

Alnus cremastogyne, a broad-leaved tree endemic to south-western China, has both commercial and restoration importance. However, little is known of its morphological, physiological and biochemical responses to drought and phosphorous (P) application. A randomized experimental design was used to investigate how drought affected A. cremastogyne seedlings, and the role that P applications play in these responses. Drought had significant negative effects on A. cremastogyne growth and metabolism, as revealed by reduced biomass (leaf, shoot and root), leaf area, stem diameter, plant height, photosynthetic rate, leaf relative water content, and photosynthetic pigments, and a weakened antioxidative defence mechanism and high lipid peroxidation level. However, the reduced leaf area and enhanced osmolyte (proline and soluble sugars) accumulation suggests drought avoidance and tolerance strategies in this tree. Applying P significantly improved the leaf relative water content and photosynthetic rate of drought-stressed seedlings, which may reflect increased anti-oxidative enzyme (superoxide dismutase, catalase and peroxidase) activities, osmolyte accumulation, soluble proteins, and decreased lipid peroxidation levels. However, P had only a slight or negligible effect on the well-watered plants. A. cremastogyne is sensitive to drought stress, but P facilitates and improves its metabolism primarily via biochemical and physiological rather than morphological adjustments, regardless of water availability.Instituto de Fisiología Vegeta

Phosphorous fertilization alleviates drought effects on Alnus cremastogyne by regulating its antioxidant and osmotic potential

Alnus cremastogyne, a broad-leaved tree endemic to south-western China, has both commercial and restoration importance. However, little is known of its morphological, physiological and biochemical responses to drought and phosphorous (P) application. A randomized experimental design was used to investigate how drought affected A. cremastogyne seedlings, and the role that P applications play in these responses. Drought had significant negative effects on A. cremastogyne growth and metabolism, as revealed by reduced biomass (leaf, shoot and root), leaf area, stem diameter, plant height, photosynthetic rate, leaf relative water content, and photosynthetic pigments, and a weakened antioxidative defence mechanism and high lipid peroxidation level. However, the reduced leaf area and enhanced osmolyte (proline and soluble sugars) accumulation suggests drought avoidance and tolerance strategies in this tree. Applying P significantly improved the leaf relative water content and photosynthetic rate of drought-stressed seedlings, which may reflect increased anti-oxidative enzyme (superoxide dismutase, catalase and peroxidase) activities, osmolyte accumulation, soluble proteins, and decreased lipid peroxidation levels. However, P had only a slight or negligible effect on the well-watered plants. A. cremastogyne is sensitive to drought stress, but P facilitates and improves its metabolism primarily via biochemical and physiological rather than morphological adjustments, regardless of water availability.Instituto de Fisiología Vegeta

Phosphorous application improves drought tolerance of phoebe zhennan

Phoebe zhennan (Gold Phoebe) is a threatened tree species in China and a valuable and important source of wood and bioactive compounds used in medicine. Apart from anthropogenic disturbances, several biotic constraints currently restrict its growth and development. However, little attention has been given to building adaptive strategies for its conservation by examining its morphological and physio-biochemical responses to drought stress, and the role of fertilizers on these responses. A randomized experimental design was used to investigate the effects of two levels of irrigation (well-watered and drought-stressed) and phosphorous (P) fertilization treatment (with and without P) to assess the morphological and physio-biochemical responses of P. zhennan seedlings to drought stress. In addition, we evaluated whether P application could mitigate the negative impacts of drought on plant growth and metabolism. Drought stress had a significant negative effect on the growth and metabolic processes of P. zhennan. Despite this, reduced leaf area, limited stomatal conductance, reduced transpiration rate, increased water use efficiency, enhanced antioxidant enzymes activities, and osmolytes accumulation suggested that the species has good adaptive strategies for tolerating drought stress. Application of P had a significant positive effect on root biomass, signifying its improved water extracting capacity from the soil. Moreover, P fertilization significantly increased leaf relative water content, net photosynthetic rate, and maximal quantum efficiency of PSII under drought stress conditions. This may be attributable to several factors, such as enhanced root biomass, decreased malondialdehyde content, and the up-regulation of chloroplast pigments, osmolytes, and nitrogenous compounds. However, P application had only a slight or negligible effect on the growth and metabolism of well-watered plants. In conclusion, P. zhennan has a strong capability for drought resistance, while P application facilitates and improves drought tolerance mostly through physio-biochemical adjustments, regardless of water availability. It is imperative to explore the underlying metabolic mechanisms and effects of different levels of P fertilization on P. zhennan under drought conditions in order to design appropriate conservation and management strategies for this species, which is at risk of extinction.Fil: Tariq, Akash. Chinese Academy of Sciences; República de ChinaFil: Pan, Kaiwen. Chinese Academy of Sciences; República de ChinaFil: Olatunji, Olusanya A.. Chinese Academy of Sciences; República de ChinaFil: Graciano, Corina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Fisiología Vegetal. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Fisiología Vegetal; ArgentinaFil: Li, Zilong. Chinese Academy of Sciences; República de ChinaFil: Sun, Feng. Chinese Academy of Sciences; República de ChinaFil: Sun, Xiaoming. Chinese Academy of Sciences; República de ChinaFil: Song, Dagang. Chinese Academy of Sciences; República de ChinaFil: Chen, Wenkai. Chinese Academy of Sciences; República de ChinaFil: Zhang, Aiping. Chinese Academy of Sciences; República de ChinaFil: Wu, Xiaogang. Chinese Academy of Sciences; República de ChinaFil: Zhang, Lin. Chinese Academy of Sciences; República de ChinaFil: Mingrui, Deng. Chinese Academy of Sciences; República de ChinaFil: Xiong, Qinli. Chinese Academy of Sciences; República de ChinaFil: Liu, Chenggang. Chinese Academy of Sciences; República de Chin

The coactivator-associated arginine methyltransferase is necessary for muscle differentiation - CARM1 coactivates myocyte enhancer factor-2

Studies with the myogenic basic helix-loop-helix and MADS box factors suggest that efficient transactivation is dependent on the recruitment of the steroid receptor coactivator (SRC) and the cofactors p300 and p300/CBP-associated factor. SRCs have been demonstrated to recruit CARM1 (coactivator-associated arginine methyltransferase-1), a member of the S-adenOSyl-L-methionine-dependent PRMTI-5 (protein-arginine N-methyltransferase-1-5) family, which catalyzes the methylation of arginine residues. This prompted us to investigate the functional role of CARM1/PRMT4 during skeletal myogenesis. We demonstrate that CARM1 and the SRC cofactor GRIP-1 cooperatively stimulate the activity of myocyte enhancer factor-2C (MEF2C). Moreover, there are direct interactions among MEF2C, GRIP-1, and CARM1. Chromatin immunoprecipitation demonstrated the in vivo recruitment of MEF2 and CARM1 to the endogenous muscle creatine kinase promoter in a differentiation-dependent manner. Furthermore, CARM1 is expressed in somites during embryogenesis and in the nuclei of muscle cells. Treatment of myogenic cells with the methylation inhibitor adenosine dialdehyde or tet-regulated CARM1 antisense expression did not affect expression of MyoD. However, inhibition of CARM1. inhibited differentiation and abrogated the expression of the key transcription factors (myogenin and MEF2) that initiate the differentiation cascade. This work clearly demonstrates that the arginine methyltransferase CARM1 potentiates myogenesis and supports the positive role of arginine methylation in mammalian differentiation

Can host reaction animal models be used to predict and modulate skin regeneration?

The study of host reactions in the biomedical and tissue engineering (TE) fields is a key issue but somehow set aside where TE constructs are concerned. Every day new biomaterials and TE constructs are being developed and presented to the scientific community. The combination of cells and biomolecules with scaffolding materials, as TE constructs, make the isolation and the understanding of the effect of each one those elements over the overall host reaction difficult. Eventually, all variables influence the host reaction and the performance of the constructs. For this reason, current assessment of the in vivo performance of TE constructs follows individual approaches, using specific animal models to independently provide insights regarding the contribution of the biomaterials/scaffolds towards the host reaction, and of all the constructs regarding their functionality. Skin wound healing progress into tissue regeneration or repair is highly dependent on the specificities of the inflammatory stage, as demonstrated by comparison between fetal and adult mechanisms. Thus, it would be expected that insights acquired from host tissue reaction evaluation to biomaterials/scaffolds would be explored to predict healing progression and improve the functionality of skin TE constructs. The rational of this review is to make a comprehensive analysis of to what extent the knowledge obtained from the evaluation of in vivo host reactions to implantable biomaterials/scaffolds has been used in the design of skin TE strategies, by promoting tissue regeneration rather than repair.T.C.S. acknowledges Grant No. RL3-TECT-NORTE-01-0124-FEDER-000020, co-financed by the North Portugal Regional Operational Programme (ON.2-O Novo Norte), under the National Strategic Reference Framework, through the European Regional Development Fund

Drought in Beijing, 1992-93

Beijing, located in northeast China, has a semiarid monsoon climate, with summer rainfall providing about 70% of the annual precipitation. This climate is conducive to crop growth, although insufficient summer rainfall in 1992–93 caused reductions in crop yields. Normalized departures of monthly precipitation (DR/R%) are shown in Figure 1. Although some months show above-normal precipitation (for example, November 1992, with a rainfall amount [43.3 mm] 7.5 times the normal), rainfall for the 1993 growing period was marked by negative departures from normal. Of the months of the 1993 growing season, only July recorded above-normal rainfall. Precipitation departures in May, September, and October 1993 were greater than 50%; as a result, summer corn did not germinate in some mountain areas, and it was difficult to seed winter wheat. Corn and wheat yields, in turn, were reduced