Severe hemorrhage because of delayed iliac vein rupture after dialysis catheter placement: Is it preventable?

Mechanical complications of femoral catheterization for hemodialysis include pseudoaneurysm, arteriovenous fistulae, neurological injury, and vessel perforation. With regard to the latter, severe hemorrhage is a rare but devastating and potentially fatal complication. We report the case of a 76-year-old female who underwent femoral catheterization for hemodialysis using ultrasound guidance. The first hemodialysis session was conducted without incident. Unfortunately, inadvertent injury and delayed perforation of the iliac vein resulted in severe hemorrhage and retroperitoneal hematoma. Surgical repair was performed. The patient was asymptomatic after the procedure and was discharged 15 days later. Based on this case and a review of the literature, we present mechanisms and ways to prevent this complication.     

Studies of non-vacuum processing of Cu-chalcogenide thin films

Cu-chalcogenide thin films were prepared using a two stage method: one step electrodeposition of CuISe and CIGSe, and the sulfurisation of CISe to prepare CISSe thin films. The films were deposited on different substrates: Mo and ITO coated glass. The optimum potentials for electrodeposition of CISe and CIGSe films were respectively selected in the range -400 to -550 mV and -650 to -700 mV (vs. SCE). The electrodeposited layers were firmly adhesive. The well known chalcopyrite structure appears after annealing at 400 degrees C under Argon for CISe. The band gap value deduced from the optical measurements is close to 1 eV. To increase this value, addition of gallium in the aqueous electrolytic solution was performed. A band gap value as high as 1.26 eV was recorded on the obtained CIGSe films. Sulfurisation of CISe layers under 5% H2S/Ar atmosphere lead to a shift of the position of the principal XRD peaks indicating the substitution of selenium atoms by sulfur atoms and thus the formation of the quaternary CISSe. Optical measurements performed on this quaternary compound show that our films exhibit a band gap value scaling from 1 eV to 1.4 eV depending on the amount of sulphur incorporated into the layers during the heat treatments.     

释放阳光地带的光伏发电潜力

拥有非常丰富的太阳能辐射资源的阳光地带,人口占全球人口总数的75%,电力需求占全球总需求的40%,该地区经济发展受到能源和环境的制约,充分利用丰富的太阳能辐射资源开发光伏发电产业,是可持续发展的重要手段。预测结果表明,范式转型情景中,这些国家的光伏装机容量甚至可达1 100 GW,也就是该地域发电总量的12%;2020年阳光地带国家光伏系统的发电成本将比建设天然气和燃油电站更具竞争力;至2030年光伏发电可以与所有以煤和天然气为燃料的中负荷电厂竞争。阳光地带国家发展股份发电目前还面临着许多障碍,这些障碍涉及到政府对燃油价格的补贴、服务于市场的能力以及能源公司的知识有限等,这些障碍有待于在发展过程中不断克服。中国和印度是阳光地带中的大国,两国的光伏制造业对阳光地带的影响很大。新能源被锁定为中国十二五规划的七大战略性新兴产业之一,中国的十二.五规划的重心是重新平衡经济增长模式,包括逐步扩大内需;国内光伏市场一旦打开,光伏在中国的发展将会非常迅速。释放阳光地带光伏潜力要求众多利益相关者共同参与协作,包括政府、银行和金融机构以及各行各业的支持,才能充分释放阳光地带的光伏发电潜力,带动光伏发电产业链的发展,成为社会经济...     

Environmental factors affecting the corrosion behavior of reinforcing steel. IV. Variation in the pitting corrosion current in relation to the concentration of the aggressive and the inhibitive anions

The pitting corrosion current of reinforcing steel is measured under natural corrosion conditions in Ca(OH)₂ solutions in presence of Cl⁻ as aggressive ions and as inhibiting anions. The corrosion current starts to flow after an induction period which depends on solution composition (concentration, pH and presence or absence of the aggressive and the inhibiting anions). The limiting corrosion currents increase with increasing the Cl⁻ ion concentration and decrease with increasing the pH and inhibiting ions concentration. The inhibition efficiency of the studied inhibiting ions increases in the following order: , and depends on the way by which the inhibitor is added to the solution. Injection of the inhibiting anions in solution causes repassivation of the pre-formed pits through competition with Cl⁻ ions for adsorption sites on metal oxide surface. The adsorbability constant and the free energy of repassivation of the inhibiting anions are calculated.     

Pitting and pitting control of Al in gluconic acid solutions - Polarization, chronoamperometry and morphological studies

The anodic behaviour of Al in gluconic acid (HG) solutions was studied. Al was found to pit in such solutions. Surface and cross-sectional views of the SEM images recorded beyond the breakdown potential (E_b) revealed the occurrence of intense pitting attack with the formation of large hemispherical pits. The effect of adding some environmentally acceptable inorganic inhibitors (tungstates, molybdates or silicates) on the pitting corrosion behaviour of Al in HG solutions was also studied. Measurements were carried out under the influence of various experimental variables based on polarization and chronoamperometric techniques. These measurements were complemented by ex situ scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) examinations of the electrode surface. The presence of these compounds in HG solutions decreased the passive current density (j_pass) and increased E_b. In HG solutions, chronoamperometric measurements showed that the anodic current density first decreased, due to growth of a passive oxide film, then increased with time after a pit incubation time, t_i and finally attained a steady-state value. Value of t_i was shortened and simultaneously the steady-state current was elevated, corresponding to an increase in the rate of pit initiation and growth, with increasing applied anodic potential and HG concentration. The rate of pit nucleation () was found to decrease to an extent depending on the type and concentration of the introduced inhibitor. The inhibitory effect of these compounds decreased in the order:  >  > .     

Influence of Manganese Oxide and Silica on the Morphological Structure of Hematite Compacts

Dry compacts of pure Fe₂O₃ and Fe₂O₃ doped with either (2–6 mass%) MnO₂, (2.5–7.5 mass%) SiO₂ or with both (2–6% MnO₂ + 7.5% SiO₂) were indurated at 1373 K for 6 hours and physically and chemically characterized. The fired compacts were isothermally reduced with pure CO gas at 1073–1373 K. The O₂‐weight loss was continuously recorded as a function of time using TGA technique. The external volume of pure and doped compacts was measured at different reduction conditions and the volume change was calculated. The structural changes accompanying the reduction process were visually and microscopically examined and the different phases were identified by X‐ray diffraction analysis. After firing, manganese ferrite (MnFe₂O₄) phase was identified in MnO₂‐doped compacts. In pure Fe₂O₃ compacts, the external volume of compacts was increased with reduction temperature, showing a maximum swelling value at 1198 K. Catastrophic swelling was observed in MnO₂‐doped Fe₂O₃ compacts, the volume change increased with MnO₂ content showing catastrophic swelling in compacts containing 6%MnO₂ at 1248 K. The catastrophic swelling was attributed to the formation of dense metallic iron whiskers and plates in a highly porous structure. Unlike in MnO₂‐doped samples, no considerable volume changes were detected in SiO₂‐doped Fe₂O₃ and (MnO₂ + SiO₂)‐doped Fe₂O₃ compacts where the presence of silica greatly hindered the swelling phenomenon at all reduction temperatures.     

Monte Carlo calculation of energy loss of hydrogen and helium ions transmitted under channelling conditions in silicon single crystal

In this work, we report on calculations of the electronic channelling energy loss of hydrogen and helium ions along Si〈1 0 0〉 and Si〈1 1 0〉 axial directions for the low energy range by using the Monte Carlo simulation code. Simulated and experimental data are compared for protons and He ions in the 〈1 0 0〉 and 〈1 1 0〉 axis of silicon. A reasonable agreement was found.Computer simulation was also employed to study the angular dependence of energy loss for 0.5, 0.8, 1, and 2 MeV channelled ⁴He ions transmitted through a silicon crystal of 3 μm thickness along the 〈1 0 0〉 axis.     

Properties of InAs grown on misoriented GaAs substrates by atmospheric pressure metal–organic vapor phase epitaxy

InAs epilayers were grown by atmospheric pressure metal–organic vapor phase epitaxy on GaAs (1 0 0) exactly oriented substrates and misoriented by 2° and 10° toward [1 1 1]A. The layers had varying thicknesses and were deposited under the same growth conditions. Atomic force microscopy analysis show that surface morphology depends on surface misorientation and presents a low root mean square. High resolution X-ray diffraction analysis and Hall effect measurements were preformed to check the substrate misorientation effect on the crystalline quality and electrical properties respectively.     

Factor structure of the CES-D and measurement invariance across gender for low-income Puerto Ricans in a probability sample.

Objective: The authors of this study aimed to evaluate 2-factor structures for the Center for Epidemiologic Studies Depression Scale (CES-D) reported in the literature to determine which one proves to be a better fit with the data on low-income Puerto Ricans living on the island. Method: The sample consisted of 3,504 civilian noninstitutionalized Puerto Ricans, ranging in age from 18 to 64 who were living in low-income areas of Puerto Rico. A confirmatory factor analysis (CFA) was implemented, and model fit was assessed with the Tucker–Lewis Index (TLI), the comparative fit index (CFI), and the root-mean-square error of approximation (RMSEA). Results: The CFA results obtained for the Radloff (1977) and Guarnaccia, Angel, and Worobey (1989) models show that neither model obtained adequate fit indexes. Exploratory factor analysis revealed that the 2-factor structure not only obtained better fit indexes (TLI = .948, CFI = .955, RMSEA = .048) but also reflected a better conceptual organization of the factors (basically divided into 2 components: Negative Affect and Positive Affect). When we assessed the model fit by gender, the model consistently fit the data for the female subsample but not for the male one. Conclusions: Results confirm the need to address the issues related to measurement equivalence for specific cultural and language gaps in assessment of depressive symptoms. Lack of factor invariance across gender also raises the question of the appropriateness of this measure for the male subsample and the need for further research in the manifestation of depression in this group. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thermal energy and economic analysis of a PCM-enhanced household envelope considering different climate zones in Morocco

This study investigates the thermal energy potentials and economic feasibility of an air-conditioned family household-integrated phase change material (PCM) considering different climate zones in Morocco. A simulation-based optimisation was carried out in order to define the optimal design of a PCM-enhanced household envelope for thermal energy effectiveness and cost-effectiveness of predefined candidate solutions. The optimisation methodology is based on coupling Energyplus^® as a dynamic simulation tool and GenOpt^® as an optimisation tool. Considering the obtained optimum design strategies, a thermal energy and economic analysis are carried out to investigate PCMs’ integration feasibility in the Moroccan constructions. The results show that the PCM-integrated household envelope allows minimising the cooling/heating thermal energy demand vs. a reference household without PCM. While for the cost-effectiveness optimisation, it has been deduced that the economic feasibility is stilling insufficient under the actual PCM market conditions. The optimal design parameters results are also analysed.