Numerical simulation of gas-assisted polymer-melt electrospinning: Parametric study of a multinozzle system for mass production

In this study, we developed a multiphysics model for simulation of a gas-assisted melt-electrospinning (GAME) process, focusing on jet formation and propagation behavior. By numerically calculating the stresses acting on the jet during a single-nozzle GAME process, the shear viscous stress was identified as the main factor with respect to jet stretch; thus, the relationship between shear viscous stress and jet thickness was investigated. The jet stretch ratio increased sharply when shear viscous stress reached the level at which jet sharpening occurred, leading to stable jet formation. We defined this stress as the critical shear viscous stress to determine stable spinnability. By imposing an electric field distribution calculated for a multi-nozzle array (number of nozzles, tip-to-tip distance, and applied voltage) on the boundary condition of the single-nozzle GAME simulation model, multinozzle GAME was simulated; this enabled proposal of a spinnability diagram for stable spinning.     

Highly Bendable and Rotational Textile Structure with Prestrained Conductive Sewing Pattern for Human Joint Monitoring

Human joints have respective ranges of motion and joint forces corresponding to each kind of joint; this necessitates considerations of the characteristics of human joints to fabricate wearable strain sensors conformable to the human body, and capable of precisely monitoring complex motions of the human body. In the present study, the “all textile‐based highly stretchable structure” that is capable of precisely sensing motions (folding and rotation) of the human joints (finger, wrist, elbow, spine, and knee) is fabricated by optimizing patterns (straight, blind, and zigzag) of conductive yarns employed as the conductive part of the strain sensor, and several textile substrates (braided elastic fabric, knit fabric, and woven fabric), having preferable elasticity and conformability employed for the fabrication of strain sensors suitable for human joints. In particular, the technology, enabling the prestraining of textile substrate, is exploited to fabricate a strain sensor that is capable of outputting selective signals corresponding to the folding motion of the spinal joint over a predetermined angle of motion, and the gait pattern of the wearer of the sensor, attached to his or her knee joint doing folding and rotational motions, is analyzed.     

Analysis on the effect of operating conditions on electrochemical conversion of carbon dioxide to formic acid

Electrochemical reduction of CO₂ to HCOOH was performed on a Sn electrode using a proton exchange membrane-embedded electrolysis cell. The effects of reaction conditions such as catholyte and anolyte types, reduction potential, catholyte pH, and reaction temperature on the amount of HCOOH and its faradaic efficiency were investigated. Four different electrolytes (KOH, KHCO₃, KCl, KHSO₄) were chosen as the candidate catholyte and anolyte; the most suitable electrolyte was chosen by monitoring the amount of HCOOH and faradaic efficiency. The effect of the pH of the selected catholyte on the conversion of CO₂ to HCOOH was also investigated. In addition, the reaction temperature was varied and its effect was studied. From the observations made, we determined the optimal reaction conditions for the production of HCOOH via the electrochemical reduction of CO₂ by a systematic approach.     

青藏线工程宿营车集中供暖系统开发与运用

本文着重介绍了针对青藏线宿营车特殊的地理、使用环境设计开发的集中供暖系统技术,并对其运用成效问题进行探讨.     

Electrical characterizations of Neutron-irradiated SiC Schottky diodes

Neutrons with an average energy of 9.8±0.8 MeV were irradiated onto silicon carbide Schottky diodes. After bombardment at a fluency of 2.75×10¹¹ neutron/cm², the Schottky barrier height, ideality factor, and the leakage currents remained unchanged. The electrical properties began to deteriorate after bombardment at a fluency of 5.5×10¹¹ neutron/cm². In this study, we demonstrate that SiC SBD is robust under neutron irradiations and is well suited for space operations up to bombardments at a fluency of 2.75×10¹¹ neutron/cm². This article is dedicated to Professor Chul Soo Lee in commemoration of his retirement from Department of Chemical and Biological Engineering of Korea University.     

Confidence and cognitive test performance.

This article examines the nature of confidence in relation to abilities, personality, and metacognition. Confidence scores were collected during the administration of Reading and Listening sections of the Test of English as a Foreign Language Internet-Based Test (TOEFL iBT) to 824 native speakers of English. Those confidence scores were correlated with performance accuracy scores from the TOEFL iBT and SAT, high school grade point averages (HS-GPA), and measures of personality and metacognition. The results of factor analyses indicate that confidence is a separate psychological trait, somewhere between ability and personality. The findings also suggest that confidence is related to, but separate from, metacognition. Gender and ethnic differences in confidence are also reported, with men and African Americans showing higher overconfidence bias than women and Whites or Hispanics, respectively. Finally, the data show small incremental validity of the confidence scores above and beyond the accuracy scores in predicting performance on the TOEFL iBT as a whole, the Writing and Speaking sections of the TOEFL iBT, and a test of numeracy. Confidence does not show incremental validity for the SAT and HS-GPA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Congenital encephalocele of the medial skull base

Intensive case management for severely psychiatrically ill patients is a relatively new phenomenon in the private sector. The authors describe a comprehensive case management program designed at Blue Cross Blue Shield of Massachusetts to meet the needs of the most severely ill psychiatric patients in a private managed care environment. The case management program emphasizes involvement of patients in creating comprehensive treatment plans; development of a relationship between case managers, patients and their families, and providers; and clinical coordination between the public and private sectors to create individualized treatment plans. The program's case managers are able to flex the benefit limitations of a managed care or indemnity plan to integrate public and private services and can enlist providers outside a managed care network. The paper describes service utilization by the first 33 patients who participated in the program for one year.     

Electrospray ionisation mass spectrometry facilitates detection of fibrinogen (Bbeta 14 Arg --> Cys) mutation in a family with thrombosis

We report the first direct detection of a fibrinogen mutation by electrospray ionisation mass spectrometry. The propositus, from a family with a history of thrombosis, came to attention after a pulmonary embolism subsequent to a spontaneous abortion. Prolonged thrombin (41 s) and reptilase times (26 s) together with an impairment of fibrinopeptide B release suggested a mutation at the thrombin cleavage site of the Bbeta chain. Direct mass analysis of purified fibrin chains from a thrombin induced clot showed that 50% of the Bbeta chains remained uncleaved. The measured mass of the mono sialo isoform of this uncleaved chain was 54150 Da, compared to a value of 54198 Da for normal Bbeta chains. This decrease of 48 Da in the intact protein is indicative of either a Bbeta 14 Arg to Cys, or Arg to Leu substitution. Heterozygosity for the Bbeta 14 Arg --> Cys mutation was verified by PCR amplification and DNA sequence analysis.