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This study is a direct hands-on epidemiological sampling of a hospital data of registered patients for tuberculosis (TB) in the Kasungu District Hospital of Malawi. The data for the year 2013 and 2014 were chosen as the latest but random sample to analyze whether the data fit in and follow the broad pattern of the country at the national level and also at the global level. The data represent convoluted results of genuine TB diagnosis and latency, but impacted by the socio-cultural mindset to obtaining health care in general. Incidences of human immunodeficiency virus (HIV) run in close parallel to TB as the former precariously enhance the vulnerability from TB infection to the disease stage. Key words: Tuberculosis (TB), Malawi, human immunodeficiency virus (HIV).

The current study has been undertaken by studying the data from the hospital registers at the Kasugu District Hospital, Malawi. The malaria cases of 2014 were chosen for the study. They typically represent disease distribution based on the ages and genders of the patients. The data suggest that the cure rates among patients under age 5 and above do not have any significant difference, contrary to the commonly anticipated outcome that the older children should have better developed immune systems and should have higher cure rates. A notable point is there are huge dichotomies between genders in terms of the reported registered cases, the cure and mortality rates. The gender differentiation in the reporting and management of malaria is understood under the contemporary socio-cultural beliefs and economic realities of the Malawian society. This analysis has been carried out from a qualitative perspective, but with an attempt to identify a pattern from a year's length of statistical data. Key words: Malaria epidemiology, malaria cases, mortality, case fatality rates.

High surface area (∼300 m 2 /g) nanostructured powders of (Nb 1−x Ir x )O 2 and (Nb 1−x Ir x )O 2 :10F (∼100 m 2 /g) have been examined as promising oxygen evolution reaction (OER) electro-catalysts for proton exchange membrane (PEM) based water electrolysis. Nb 2 O 5 and 10 wt.% F doped Nb 2 O 5 powders were prepared by a low temperature sol-gel process which were then converted to solid solution (Nb,Ir)O 2 and 10 wt.% F doped (Nb,Ir)O 2 [(NbIr)O 2 :10F] electro-catalysts by soaking in IrCl 4 followed by heat treatment in air. Electro-catalyst powders of optimal composition (Nb 0.75 Ir 0.25 )O 2 :10F with ∼75 at.% reduction in noble metal content exhibited comparable OER activity to commercial hydrated IrO 2 and nanostructured in-house chemically synthesized IrO 2 . The (Nb,Ir)O 2 :10F electro-catalyst demonstrated excellent long term structural/corrosion stability comparable to in-house chemically synthesized pure IrO 2 :10F. First-principles calculations of the total energies, electronic structures and cohesive energies of the model systems have been performed and correlated to the excellent activity, long term stability of (Nb,Ir)O 2 :F for OER obtained experimentally.

In the present study, microscale transport phenomena in gas diffusion layers (GDLs) with gradient porosities are investigated statistically. A series of GDLs are randomly generated with linear and nonlinear gradient porosities at a 95% confidence level to reflect the heterogeneous microstructures. Straight-cylindrical carbon fibers with a uniform diameter are randomly arranged layer-by-layer and then treated with various polytetrafluoroethylene (PTFE) loadings. Furthermore, the reactant transport phenomena throughout the GDLs are simulated using lattice Boltzmann method (LBM). Then, the corresponding mass transport characteristics (i.e., permeability, tortuosity, and effective diffusion coefficient) are predicted in a series of GDL samples. The predicted data reveal an inverse relationship between permeability and PTFE loading. Moreover, the results show that GDLs with gradient porosities are more favourable to the reactant gas diffusion, leading to larger permeability than those of GDLs with uniform porosities. Besides, electrical and thermal conductivities of GDLs are computed in both in-plane and through-plane directions, and show good agreement with published experimental data. These statistical results show that the microscopic transport characteristics of PTFE-treated GDLs with gradient porosities are strongly affected by porosity distribution and PTFE loading. The proposed model can be utilized to optimize GDL structures and investigate the effect of PTFE on microscale transport characteristics of GDLs.

Desiccating human red blood cells (RBCs) to increase their storage life has been the subject of intense research for a number of years. However, drying RBCs invariably compromises their integrity and has detrimental effects on hemoglobin function due to autoxidation. We have previously demonstrated an RBC desiccation and rehydration process that preserves RBC antigenic epitopes better than frozen RBCs. This study expands on those observations by examining what effects this desiccation process has on RBC hemoglobin function with respect to oxygen binding properties. In this paper, we examined RBCs from normal donors which were desiccated to 25% moisture content and stored dry for 2 weeks at room temperature prior to rehydration with plasma followed by structural and functional studies. Our data showed that approximately 98% of the RBCs were intact upon rehydration based on hemolysis assays. Oxygen dissociation curves for the desiccated/rehydrated RBCs showed a left shift compared to fresh RBCs (pO2 = 17 mmHg vs. 26 mmHg, respectively). The desiccated/rehydrated RBCs also showed an increase in methemoglobin compared to fresh RBCs (4.5% vs 0.9%, respectively). 2,3-Diphosphoglycerate concentration of the desiccated/rehydrated RBCs was reduced by 20%. In conclusion, although this RBC dehydration process preserves RBC integrity and hemoglobin oxygen binding properties better than most other dehydration techniques described so far, further optimization and long-term studies are needed to make this procedure acceptable for human transfusion.

The high voltage spinel form of LiMn1.5Ni0.5O4 (LMNO) with a particle size ∼10–40 nm has been synthesized for the first time using high energy mechanical milling (HEMM) followed by low temperature thermal treatments using Li2O, MnO2 and NiO as the starting precursors. The nanostructured LMNO cathode, synthesized by the simple, but effective HEMM process followed by thermal treatments to refine the structure in the temperature range ∼573–1073 K, exhibits a reversible capacity ∼120–110 mAh/g when cycled at a rate of ∼20 mA/g in the potential window ∼3.6–5.1 V. The electrochemical results are comparable to capacity values reported in the literature for LMNO derived using various other methods suggesting the efficacy of HEMM as an attractive and viable alternative approach for synthesizing battery grade high voltage spinel phase, LMNO.

Fluorine doped iridium oxide (IrO2:F) powders with varying F content ranging from 0 to 20 wt.% has been synthesized by using a modification of the Adams fusion method. The precursors (IrCl4 and NH4F) are mixed with NaNO3 and heated to elevated temperatures to form high surface area nanomaterials as electro-catalysts for PEM based water electrolysis. The catalysts were then coated on a porous Ti substrate and have been studied for the oxygen evolution reaction in PEM based water electrolysis. The IrO2:F with an optimum composition of IrO2:10 wt.% F shows remarkably superior electrochemical activity and chemical stability compared to pure IrO2. The results have also been supported via kinetic studies by conducting rotating disk electrode (RDE) experiments. The RDE studies confirm that the electro-catalysts follow the two electron transfer reaction for electrolysis with calculated activation energy of ∼25 kJ mol−1. Single full cell tests conducted also validate the superior electrochemical activity of the 10 wt.% F doped IrO2.

Purpose: To evaluate the factors affecting the bone union time and the occurrence of nonunion after intramedullary nailing of subtrochanteric femoral fractures in adults. Materials and Methods: We retrospectively reviewed data from 31 patients (22 men and 9 women) who had undergone femoral intramedullary nailing at least 1 year post-operatively and analyzed the bone union time, nonunion rates, and factors that affected the bone union time according to the fracture classification (AO and Fielding classifications), comminution of the medial cortex, reduction method, and additional cerclage wiring. Results: The average union time was 26.4 weeks. There were no differences in the bone union time according to the fracture classification, reduction method, or additional cerclage wiring. Significant differences were found in the bone union time between the medial cortex comminution and non-comminution groups. A relatively strong positive correlation was detected between the degree of post-operative displacement and the bone union time. Nonunion occurred in three cases and there was no failure of implants. Conclusion: The bone union time was not affected by the reduction method nor additional cerclage wiring in intramedullary nailing of subtrochanteric femur fractures. Comminution of the medial cortex and the degree of the postoperative displacement of fractures contributed to the delayed time of union.

Identification of electro-catalysts containing non-noble metal or significantly reduced amounts of expensive noble metals ( e.g. RuO 2 ) is highly desirable. Development of such a catalyst with comparable electrochemical performance to the standard noble metal oxide for proton exchange membrane (PEM) based water electrolysis would constitute a pioneering breakthrough in hydrogen generation by water electrolysis. In line with these goals, by exploiting a two-pronged theoretical first principles and experimental approach herein we demonstrate that a nano-structured solid solution of SnO 2 :10 wt% F containing only 20 at.% RuO 2 [ e.g. (Sn 0.80 Ru 0.20 )O 2 :10F] displays a remarkably similar electrochemical activity and moreover, comparable or even much improved electrochemical stability and durability compared to pure the noble metal counterpart, RuO 2 . Density functional theory calculations have demonstrated direct dependence of the catalytic activity on the electronic structure peculiarities of the F-doped (Ru,Sn)O 2 which corresponds well with the experimental results.

An inexpensive, facile, and high throughput synthesis of silicon nanoparticles was achieved by the mechano-chemical reduction reaction of magnesium silicide (Mg 2 Si) and silicon monoxide (SiO) using a high energy mechanical milling (HEMM) technique followed by acid leaching. Characterization of the resultant product using X-Ray diffraction, Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and surface area analyses was performed at various stages of the synthesis process. XRD patterns show that the final product formed is single phase silicon and the nanocrystalline nature was confirmed by the shifted transverse optical (TO) band, characteristic of nc-Si determined by Raman analysis. SEM and TEM shows the presence of particles of different sizes in the range of few nanometers to agglomerates of few microns which is consistent with products obtained from mechanical milling. BET measurements show a very high specific surface area (SSA) of ~190 m 2 /g obtained due to acid leaching which is also validated by the porous nature of the particles confirmed by the SEM images.

Advanced dual control gate with surrounding floating gate (DC-SF) cell process and operation schemes are successfully developed for 3-D nand flash memories. To improve performance and reliability of DC-SF cell, new metal control gate last (MCGL) process is developed. The MCGL process can realize a low resistive tungsten (W) metal wordline, a low damage on tunnel oxide/inter-poly dielectric (IPD), and a preferable floating gate (FG) shape. Also, new read and program operation schemes are developed. In the new read operation, the higher and lower Vpass-read are alternately applied to unselected control gates to compensate lowering FG potential to be a pass transistor. In the new program scheme, the optimized Vpass are applied to neighbor WL of selected WL to prevent program disturb and charge loss through IPD. Thus, by using the MCGL process and new read/program schemes, the high performance and reliability of the DC-SF cell can be realized for 3-D nand flash memories.

The growth kinetics of WSi2 coating formed by chemical vapor deposition (CVD) of Si on a W substrate at temperatures between 1000 and 1200 °C using SiCl4–H2 gas mixtures was investigated and its isothermal oxidation resistance in 80% Ar–20% O2 atmosphere was evaluated at temperatures between 800 and 1300 °C. WSi2 coating grew with a parabolic rate law after an initial incubation period, indicating the diffusion-controlled growth. The activation energy for growth of WSi2 coating was about 42.5 kcal/mol. The isothermal oxidation rate of WSi2 coating increased with increasing oxidation temperature but rapidly decreased at 1300 °C. The oxidation product of WSi2 coating was composed of the WO3 particles embedded in the amorphous SiO2 matrix at below 1200 °C but consisted of only SiO2 phase at 1300 °C. The fast oxidation behavior of WSi2 coating at below 1200 °C was attributed to the formation of many cracks and pores, i.e. short-circuit diffusion path of oxygen, within the oxide scale, which resulted from the internal stress generated both by the large volume expansion caused by the oxidation reactions of WSi2 and by the evaporation of WO3 phase. The slow oxidation behavior of WSi2 coating at 1300 °C was due to the exclusive formation of a slow-growing continuous SiO2 scale by the rapid evaporation of WO3 phase.

This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or "nanofluids," was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (�10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise. � 2009 American Institute of Physics.

A chromophore in which zinc porphyrin donors are linked through their meso positions by ethynyl bridges to a bis(indolinylidenemethyl) squaraine core has been synthesized using Sonogashira coupling. The chromophore exhibits a two-photon absorption spectrum characterized by a peak cross section of 11,000 GM and, more unusually, also exhibits a large cross section of >780 GM over a photon-wavelength window 750 nm in width.