Laplaciens de graphes infinis I Graphes m\'etriquement complets

We introduce the weighted graph Laplacian and the notion of Schr\"odinger operator on a locally finite weighted graph . Concerning essential self-adjointness, we extend Wojciechowski's and Dodziuk's results for graphs with vertex constant weight. The main result in this work states that on any metrically complete weighted graph with bounded degree, the Laplacian is essentially self-adjoint and the same holds for the Schr\"odinger operator provided the associated quadratic form is bounded from below. We construct for the proof a strictly positive and harmonic function which allows us to write any Schr\"odinger operator as a weighted graph Laplacian modulo a unitary transform

Metabolomics analysis as a tool to measure cobalt neurotoxicity : an in vitro validation

In this study, cobalt neurotoxicity was investigated in human astrocytoma and neuroblastoma (SH-SY5Y) cells using proliferation assays coupled with LC–MS-based metabolomics and transcriptomics techniques. Cells were treated with a range of cobalt concentrations between 0 and 200 µM. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay revealed cobalt cytotoxicity and decreased cell metabolism in a dose and time-dependent manner was observed by metabolomics analysis, in both cell lines. Metabolomic analysis also revealed several altered metabolites particularly those related to DNA deamination and methylation pathways. One of the increased metabolites was uracil which can be generated from DNA deamination or fragmentation of RNA. To investigate the origin of uracil, genomic DNA was isolated and analyzed by LC–MS. Interestingly, the source of uracil, which is uridine, increased significantly in the DNA of both cell lines. Additionally, the results of the qRT-PCR showed an increase in the expression of five genes Mlh1, Sirt2, MeCP2, UNG, and TDG in both cell lines. These genes are related to DNA strand breakage, hypoxia, methylation, and base excision repair. Overall, metabolomic analysis helped reveal the changes induced by cobalt in human neuronal-derived cell lines. These findings could unravel the effect of cobalt on the human brain

Energy Consumption, Carbon Emissions and Global Warming Potential of Wolfberry Production in Jingtai Oasis, Gansu Province, China

During the last decade, China's agro-food production has increased rapidly and been accompanied by the challenge of increasing greenhouse gas (GHG) emissions and other environmental pollutants from fertilizers, pesticides, and intensive energy use. Understanding the energy use and environmental impacts of crop production will help identify environmentally damaging hotspots of agro-production, allowing environmental impacts to be assessed and crop management strategies optimized. Conventional farming has been widely employed in wolfberry (Lycium barbarum) cultivation in China, which is an important cash tree crop not only for the rural economy but also from an ecological standpoint. Energy use and global warming potential (GWP) were investigated in a wolfberry production system in the Yellow River irrigated Jingtai region of Gansu. In total, 52 household farms were randomly selected to conduct the investigation using questionnaires. Total energy input and output were 321,800.73 and 166,888.80 MJ ha−1, respectively, in the production system. The highest share of energy inputs was found to be electricity consumption for lifting irrigation water, accounting for 68.52%, followed by chemical fertilizer application (11.37%). Energy use efficiency was 0.52 when considering both fruit and pruned wood. Nonrenewable energy use (88.52%) was far larger than the renewable energy input. The share of GWP of different inputs were 64.52% electricity, 27.72% nitrogen (N) fertilizer, 5.07% phosphate, 2.32% diesel, and 0.37% potassium, respectively. The highest share was related to electricity consumption for irrigation, followed by N fertilizer use. Total GWP in the wolfberry planting system was 26,018.64 kg CO2 eq ha−1 and the share of CO2, N2O, and CH4 were 99.47%, 0.48%, and negligible respectively with CO2 being dominant. Pathways for reducing energy use and GHG emission mitigation include: conversion to low carbon farming to establish a sustainable and cleaner production system with options of raising water use efficiency by adopting a seasonal gradient water pricing system and advanced irrigation techniques; reducing synthetic fertilizer use; and policy support: smallholder farmland transfer (concentration) for scale production, credit (small- and low-interest credit) and tax breaks

Design rules for non-Manhattan shapes

An approach to MEMS Computer Aided Design tools has been to make use of Integrated Circuits CAD suites with specific enhancements for MEMS designs. Extending the IC Design Rule Checkers to non-Manhattan shapes is one of these needed enhancements. IF anecdotally used in IC designs, non-manhattan shapes are intensively used in todays state of the art MEMS products. High performance gyroscopes and yaw rate sensors made in surface micromachining processes feature spiral springs and torsional combdrives made of toroidal fingers. Applying classical DRCs to these layouts generate thousands of false errors. The errors are false because they do not affect the manufacturability of the device. But because of their number, they prevent the designers from detecting real errors in their layout. Most false errors are generated by rounding floating point vertices' coordinates, translating different data types and snapping points to a grid. This paper presents a new methodology to eliminate false errors generated by the DRC of non-manhattan shapes. This methodology includes adding a tolerance factor to Microsystem design rules with respect to the geometric properties of non-manhattan shapes and the manufacturing grid parameters, closely controlling the vertices coordinates when automatically generating the non manhattan shapes and controlling the snapping on the grid. This methodology has been implemented in MEMSCAP Microsystem engineering kits and has been validated for three foundry design rules: BOSCH, SensoNor, and AM

Properties of Cement and Geopolymer Mortars Reinforced with Glass Fibres

A composite material consists of high-strength fibres incorporated into a matrix. The incorporated fibres act as the primary load carrying constitute, whereas, the matrix keeps them in desired orientation and location. The ordinary Portland cement is generally regarded as a brittle material having low tensile strength and strain capacity. Recently, fibres such as basalt, cotton, asbestos, glass, and carbon fibres were used as an alternative to conventional steel reinforcements. Geopolymer cement was introduced as an alternative to ordinary Portland cement because it possesses reduced carbon footprint, and it effectively utilises industrial waste materials (such as fly ash, slag). On the down side, it tensile and bending strength is poor due to ceramic-like nature and a number of reinforcements (such as glass fibres) have been considered for improving their mechanical properties. In this experimental investigation, glass fibres were added to geopolymer and ordinary Portland cement based mortars in different volume proportions such as 0%, 1.25 %, 1.50 %, and 1.75 % by volume. The microstructure analysis revealed that the addition of glass fibres led to an increase in the porosity of the samples. The fractured samples containing glass fibres experienced multidirectional micro-cracking instead of control sample, which experienced single large crack leading to sample failure. All of the GFRC and GFGP samples showed well-defined stress-strain behaviour influenced considerably by the addition of glass fibres. The GFRC and GFGP samples with 1.25 % of glass fibres experienced minimum cracking and exhibited maximum improvement in the compressive (~43%) and tensile strengths (~55%)

Effects of pozzolans together with steel and polypropylene fibers on mechanical properties of RCC pavements

Effects of pozzolans and fibers on mechanical properties of RCC are addressed. The mechanical properties were evaluated using optimum moisture with different amounts of pozzolans, steel and polypropylene fibers. Using pozzolans, maximum increase in compressive strength was observed to occur between 28 and 90 days of age, rupture modulus was found to decrease; but toughness indices did not change considerably. The influence of steel fibers on compressive strength was often more significant than that of PP fibers; but neither steel nor PP fibers did contribute to increase in the rupture modulus independently from pozzolans. Also, the toughness indices increased when steel fibers were used. © 2011 Elsevier Ltd. All rights reserved

Association of interleukin-18 promoter polymorphism with comorbid conditions of cardiovascular disease

Objectives: Cardiovascular disease (CVD) is one of the most clinically relevant pathologies that remains the largest single contributor to global mortality. It is often associated with more than one comorbid condition, which obscures its clinical outcome. The current study aimed to evaluate the possible association of interleukin-18 (IL-18) promoter polymorphism with comorbid conditions of CVD. Methods: We used case-control comparison of specific genotypes of three clinically relevant IL-18 polymorphism hotspots, viz. −656 T/G (rs1946519), −607C/A (rs1946518), and −137 G/C (rs187238) with commonly associated comorbid conditions of CVD such as diabetes, hypertension, and dyslipidemia. For this study, whole blood of CVD patients and healthy control subjects were collected in a citrate coated/plain tube. The routine biochemical parameters were estimated in each sample, and DNA samples were extracted for PCR amplification for further sequencing of targeted amplicons using Sanger method. Results: The studied biochemical parameters showed a significant increase in CVD patients compared with control individuals. Fasting glucose and glycosylated hemoglobin (HBA1C) showed an increase from 4.82 to 8.6 (p < 0.05) and 4.33 to 8.2 (p < 0.05), respectively. The results showed a statistically significant association with CVD-diabetes and CVD-hypertension group with GG, GC, and CC genotype at IL-18 gene locus, rs187238. On the other hand, the CVD-dyslipidemia group showed a positive association with allele distribution at the same hotspot. In addition, the GG, GT, and TT genotype and G and T allele distribution at rs1946519 locus showed statistically significant association with CVD-diabetes, CVD-hypertension, and CVD-dyslipidemia p compared with control subjects. We also observed a statistically significant association of dyslipidemia with three genotypic combinations viz. (rs1946518 AA, rs1946519 GG, rs187238 GG); (rs1946518 AA, rs1946519 GT, rs187238 GG), and (rs1946518 AA, rs1946519 TT, rs187238 GG). Conclusions: Based on our study, we conclude that IL-18 loci, rs1946519 has a significant association with each studied comorbid condition and can be considered a prognostic marker of CVD and comorbidities. Our results are anticipated to be utilized to launch a significant pharmaco-genomic investigation that could identify patients with comorbidities who are more likely to develop CVD