Prevalence of malnutrition in hemodialysis patients: A single-center study in Palestine

Only a few studies have been published on the nutritional status of hemodialysis (HD) patients in Arab countries. The aim of this study was to determine the nutritional status and prevalence of malnutrition and its predictors among HD patients at An-Najah National University Hospital, Nablus, Palestine. A cross-sectional study was carried out on HD patients in this hospital. Seven-Point Subjective Global Assessment (7-point SGA) was used to assess the nutritional state of HD patients. Biochemical tests were obtained during the study period from medical files of the studied patients. A total of 106 HD patients were recruited for this study and assessed for nutritional status. More than half (60, 56.6%) of the recruited patients were males. The majority of the patients (86.8%) were above 45 years of age. Hypertension (65, 61.3%) was the most common comorbid conditions followed by diabetes mellitus (51, 48.1%). The median SGA score was 5.57 (5–6). More than half of the HD patients (56; 52.8%) were well-nourished while the remaining (50, 47.2%) had mild-to-moderate malnourishment. Univariate analysis indicated that SGA score was significantly higher in HD patients with college education (P = 0.026), nondiabetic (P = 0.044), nonhypertensive (P = 0.037), and those with current occupation (P = 0.025). No significant correlation was found between SGA score and potassium level (P = 0.134), calcium level (P = 0.883), albumin (P = 0.282), and phosphate level (P = 0.419). However, significant positive correlation was found between SGA core and hemoglobin level (P = 0.019; r = 0.227). Multivariate analysis showed no significant predictors of SGA score. In this pilot single-center study, malnutrition was detected in almost half of HD patients using SGA scale. Development of nutritional assessment protocols for HD is an important issue and needs to be followed up by health-care teams in HD centers

Stopping Voltage-Dependent PCM and RRAM-Based Neuromorphic Characteristics of Germanium Telluride

Recently, phase change chalcogenides, such as monochalcogenides, are reported as switching materials for conduction-bridge-based memristors. However, the switching mechanism focused on the formation and rupture of an Ag filament during the SET and RESET, neglecting the contributions of the phase change phenomenon and the distribution and re-distribution of germanium vacancies defects. The different thicknesses of germanium telluride (GeTe)-based Ag/GeTe/Pt devices are investigated and the effectiveness of phase loops and defect loops future application in neuromorphic computing are explored. GeTe-based devices with thicknesses of 70, 100, and 200 nm, are fabricated and their electrical characteristics are investigated. Highly reproducible phase change and defect-based characteristics for a 100 nm-thick GeTe device are obtained. However, 70 and 200 nm-thick devices are unfavorable for the reliable memory characteristics. Upon further analysis of the Ag/GeTe/Pt device with 100 nm of GeTe, it is discovered that a state-of-the-art dependency of phase loops and defect loops exists on the starting and stopping voltage sweeps applied on the top Ag electrode. These findings allow for a deeper understanding of the switching mechanism of monochalcogenide-based conduction-bridge memristors.Computer Engineerin

Field-Directed Sputter Sharpening for Tailored Probe Materials and Atomic-Scale Lithography

Fabrication of ultra-sharp probes is of interest for many applications, including scanned probe microscopy and electron-stimulated patterning of surfaces. These techniques require reproducible ultra-sharp metallic tips, yet the efficient and reproducible fabrication of these consumable items has remained an elusive goal. We describe a novel biased-probe field-directed sputter sharpening technique, applicable to conductive materials, which produces nanometer and sub-nanometer sharp W, Pt-Ir, and W-HfB2 tips able to perform atomic-scale lithography on Si. Compared with traditional probes fabricated by etching or conventional sputter erosion, field-directed sputter sharpened probes have smaller radii and produce lithographic patterns 18 – 26% sharper with atomic-scale lithographic fidelity.Office of Naval Research Grant N00014-06-10120Defense Advanced Research Project Agency and Space and Naval Warfare Center, San Diego contract N66001-08-C-2040National Science Foundation grant CHE 10-38015National Science Foundation grant DMR 10-05715National Science Foundation grant CHE 07-50422published or submitted for publicationis peer reviewe