High sensitivity and multifunctional micro-Hall sensors fabricated using InAlSb/InAsSb/InAlSb heterostructures

Further diversification of Hall sensor technology requires development of materials with high electron mobility and an ultrathin conducting layer very close to the material's surface. Here, we describe the magnetoresistive properties of micro-Hall devices fabricated using InAlSb/InAsSb/InAlSb heterostructures where electrical conduction was confined to a 30 nm-InAsSb two-dimensional electron gas layer. The 300 K electron mobility and sheet carrier concentration were 36 500 cm(2) V-1 s(-1) and 2.5 x 10(11) cm(-2), respectively. The maximum current-related sensitivity was 2 750 V A(-1) T-1, which was about an order of magnitude greater than AlGaAs/InGaAs pseudomorphic heterostructures devices. Photolithography was used to fabricate 1 mu m x 1 mu m Hall probes, which were installed into a scanning Hall probe microscope and used to image the surface of a hard disk

Effect of varying magnetic fields on targeted gene delivery of nucleic acid-based molecules

This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.The importance of high transfection efficiency has been emphasized in many studies investigating methods to improve gene delivery. Accordingly, non-viral transfection agents are widely used as transfection vectors to condense oligonucleotides, DNA, RNA, siRNA, deliver into the cell, and release the cargo. Polyethyleneimine (PEI) is one of the most popular non-viral transfection agents. However, the challenge between high transfection efficiency and toxicity of the polymers is not totally resolved. The delivery of necessary drugs and genes for patients and their transport under safe conditions require carefully designed and controlled delivery systems and constitute a critical stage of patients’ treatment. Compact systems are considered as the strongest candidate for the preparation and delivery of drugs and genes under leak free and safe conditions because of their low energy consumption, low waste disposal, parallel and fast processing capabilities, removal of human factor, high mixing capabilities, enhanced safety, and low amount of reagents. Motivated by this need in the literature, a platform for gene delivery via magnetic actuation of nanoparticles was developed in this study. The use of PEI-SPION (Super paramagnetic ironoxide nanoparticles) as transfection agents in in vitro studies was investigated with the effect of varying magnetic fields provided by a special magnetic system design, which was used as magnetic actuator offering different magnet's turn speeds and directions in the system. Results obtained from magnetic actuator systems were compared to the experiments without actuation and significant enhancement was observed in the transfection efficacies

The standardised copy of pentagons test

<p>Abstract</p> <p>Background</p> <p>The 'double-diamond copy' task is a simple paper and pencil test part of the Bender-Gestalt Test and the Mini Mental State Examination (MMSE). Although it is a widely used test, its method of scoring is crude and its psychometric properties are not adequately known. The aim of the present study was to develop a sensitive and reliable method of administration and scoring.</p> <p>Methods</p> <p>The study sample included 93 normal control subjects (53 women and 40 men) aged 35.87 ± 12.62 and 127 patients suffering from schizophrenia (54 women and 73 men) aged 34.07 ± 9.83.</p> <p>Results</p> <p>The scoring method was based on the frequencies of responses of healthy controls and proved to be relatively reliable with Cronbach's α equal to 0.61, test-retest correlation coefficient equal to 0.41 and inter-rater reliability equal to 0.52. The factor analysis produced two indices and six subscales of the Standardised Copy of Pentagons Test (SCPT). The total score as well as most of the individual items and subscales distinguished between controls and patients. The discriminant function correctly classified 63.44% of controls and 75.59% of patients.</p> <p>Discussion</p> <p>The SCPT seems to be a satisfactory, reliable and valid instrument, which is easy to administer, suitable for use in non-organic psychiatric patients and demands minimal time. Further research is necessary to test its psychometric properties and its usefulness and applications as a neuropsychological test.</p

Unit Nonresponse in a Population-Based Study of Prostate Cancer

Low unit response rates can increase bias and compromise study validity. Response rates have continued to fall over the past decade despite all efforts to increase participation. Many factors have been linked to reduced response, yet relatively few studies have employed multivariate approaches to identify characteristics that differentiate respondents from nonrespondents since it is hard to collect information on the latter. We aimed to assess factors contributing to enrollment of prostate cancer (PCa) patients. We combined data from the North Carolina-Louisiana (LA) PCa Project’s LA cohort, with additional sources such as US census tract and LA tumor registry data. We included specific analyses focusing on blacks, a group often identified as hard to enroll in health-related research. The ability to study the effect of Hurricane Katrina, which occurred amidst enrollment, as a potential determinant of nonresponse makes our study unique. Older age (≥ 70) for blacks (OR 0.65) and study phase with respect to Hurricane Katrina for both races (OR 0.59 for blacks, OR 0.48 for whites) were significant predictors of participation with lower odds. Neighborhood poverty for whites (OR 1.53) also was a significant predictor of participation, but with higher odds. Among blacks, residence in Orleans parish was associated with lower odds of participation (OR 0.33) before Katrina. The opposite occurred in whites, with lower odds (OR 0.43) after Katrina. Our results overall underscore the importance of tailoring enrollment approaches to specific target population characteristics to confront the challenges posed by nonresponse. Our results also show that recruitment-related factors may change when outside forces bring major alterations to a population's environment and demographics

A Review of Recent Aeroelastic Analysis Methods for Propulsion at NASA Lewis Research Center

This report reviews aeroelastic analyses for propulsion components (propfans, compressors and turbines) being developed and used at NASA LeRC. These aeroelastic analyses include both structural and aerodynamic models. The structural models include a typical section, a beam (with and without disk flexibility), and a finite-element blade model (with plate bending elements). The aerodynamic models are based on the solution of equations ranging from the two-dimensional linear potential equation to the three-dimensional Euler equations for multibladed configurations. Typical calculated results are presented for each aeroelastic model. Suggestions for further research are made. Many of the currently available aeroelastic models and analysis methods are being incorporated in a unified computer program, APPLE (Aeroelasticity Program for Propulsion at LEwis)

A standardized scoring method for the copy of cube test, developed to be suitable for use in psychiatric populations

BACKGROUND: Although the 'copy of cube test', a version of which is included in the Short Test of Mental Status (STMS), has existed for years, little has been done to standardize it in detail. The aim of the current study was to develop a novel and detailed standardized method of administration and scoring this test. METHODS: The study sample included 93 healthy control subjects (53 women and 40 men) aged 35.87 ± 12.62 and 127 patients suffering from schizophrenia (54 women and 73 men) aged 34.07 ± 9.83 years. The psychometric assessment included the Positive and Negative Symptoms Scale (PANSS) the Young Mania Rating Scale (YMRS), and the Montgomery-Åsberg Depression Rating Scale (MADRS). RESULTS: A scoring method was developed based on the frequencies of responses of healthy controls. Cronbach's α was equal to 0.75 and inter-rater reliability was 0.90. Three indices and five subscales of the Standardized Copy of the Cube Test (SCCT) were eventually developed. They included the Deficit Index (DcI), which includes the Missing Elements (ME) Mirror Image (M) subscales, the Deformation Index (DfI) which includes the Deformation (D) and the Rotation (R) subscales and the Closing-In Index (CiI). DISCUSSION: The SCCT seems to be a reliable, valid and sensitive to change instrument for the testing of psychiatric patients. The great advantage of this instrument is the fact that it only requires paper and a pencil, and is this easily administered and brief. Further research is necessary to test its usefulness as a neuropsychological test

A subcutaneous adipose tissue-liver signalling axis controls hepatic gluconeogenesis.

The search for effective treatments for obesity and its comorbidities is of prime importance. We previously identified IKK-ε and TBK1 as promising therapeutic targets for the treatment of obesity and associated insulin resistance. Here we show that acute inhibition of IKK-ε and TBK1 with amlexanox treatment increases cAMP levels in subcutaneous adipose depots of obese mice, promoting the synthesis and secretion of the cytokine IL-6 from adipocytes and preadipocytes, but not from macrophages. IL-6, in turn, stimulates the phosphorylation of hepatic Stat3 to suppress expression of genes involved in gluconeogenesis, in the process improving glucose handling in obese mice. Preliminary data in a small cohort of obese patients show a similar association. These data support an important role for a subcutaneous adipose tissue-liver axis in mediating the acute metabolic benefits of amlexanox on glucose metabolism, and point to a new therapeutic pathway for type 2 diabetes

Immunodepletion in xenotransplantation

Xenograft transplantation is perhaps the most immunologically difficult problem in transplantation today. An overwhelming hyperacute rejection reaction (HAR) occurs within minutes of organ implantation. Preformed antibodies are thought to initiate this process. We used a pig-to-dog renal xenograft transplant model and investigated methods of decreasing the severity of hyperacute rejection. Female pigs weighing 15-20 kg were used as donors. Recipients were mongrel dogs weighing 15-25 kg. Experimental dogs were all given a number of treatments of IgG depletion using an antibody removal system (Dupont-Excorim). This machine immunoadsorbs plasma against a column containing immobilized staphylococcal protein A, which is known to bind the IgG Fc receptor. An 84% reduction in the IgG levels and a 71% reduction in IgM levels was achieved. Postoperative assessment was made of urine output, time to onset of HAR, and histopathological examination of the rejected kidneys. Although cross-matches between donor lymphocytes and recipient sera remained strongly positive in the treated dogs, there was a two- to fourfold reduction in the titers. The time to onset of HAR was prolonged in the experimental group, and the urine output was increased slightly. The histopathologic changes in the experimental group generally showed signs of HAR, but of less intensity than in the nonimmunodepleted control group. © 1990 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted