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Hysteresis and transient behavior in current-voltage measurements of hybrid-perovskite absorber solar cells

Hybrid organo-metal halide perovskites are an exciting new class of solar absorber materials and have exhibited a rapid increase in solar cell efficiencies throughout the past two years to over 17% in both meso-structured and thin-film device architectures. We observe slow transient effects causing hysteresis in the current-voltage characterization of these devices that can lead to an over- or und

Mapping the surface phase diagram of GaAs(001) using droplet epitaxy

We combine droplet epitaxy with low-energy electron microscopy imaging techniques to map the surface phase diagram of GaAs(001). The phase patterns produced in droplet epitaxy are interpreted using a simple model which links the spatial coordinates of phase boundaries to the free energy. It is thereby possible to gain important information on surface phase stability, based on the observed sequenti

Pre-contrast T1 and cartilage thickness as confounding factors in dGEMRIC when evaluating human cartilage adaptation to physical activity

Background: The dGEMRIC (delayed Gadolinium-Enhanced MRI of Cartilage) technique has been used in numerous studies for quantitative in vivo evaluation of the relative glycosaminoglycan (GAG) content in cartilage. The purpose of this study was to determine the influence of pre-contrast T1 and cartilage thickness when assessing knee joint cartilage quality with dGEMRIC. Methods: Cartilage thickness

Heritability of Caries Scores, Trajectories, and Disease Subtypes

Previous studies report that dental caries is partially heritable, but there is uncertainty in the magnitude of genetic effects and little understanding of how genetic factors might influence caries progression or caries subtypes. This study aimed to estimate the relative importance of genetic and environmental factors in the etiology of different caries outcomes using a twin-based design. Analysi

Gross, net, and new job creation by entrepreneurs

Using a dataset with over 24 million year-employment observations and the universe of more than 230,000 entries into entrepreneurship in one economy we analyze the gross (including the founders), net (excluding the founders), and new (jobs to the former unemployed or those outside the labor force) job creation by entrepreneurs two and six years after start-up. These novel measures of job creation

Cerebro-spinal fluid biomarker levels : phosphorylated tau (T) and total tau (N) as markers for rate of progression in Alzheimer's disease

BACKGROUND: We investigated the potential associations between cerebro-spinal fluid (CSF) levels of phosphorylated tau (P-tau) and total tau (T-tau) with short-term response to cholinesterase inhibitor (ChEI) treatment, longitudinal outcome and progression rates in Alzheimer's disease (AD). METHODS: This prospective, observational study included 129 participants clinically diagnosed with mild-to-m

Oral Contraceptive Use and Breast Cancer Risk : Retrospective and Prospective Analyses From a BRCA1 and BRCA2 Mutation Carrier Cohort Study

Background: For BRCA1 and BRCA2 mutation carriers, the association between oral contraceptive preparation (OCP) use and breast cancer (BC) risk is still unclear.Methods: Breast camcer risk associations were estimated from OCP data on 6030 BRCA1 and 3809 BRCA2 mutation carriers using age-dependent Cox regression, stratified by study and birth cohort. Prospective, left-truncated retrospective and fu

A new heteropentanuclear complex containing the [Fe2 IIIZn3 II(μ-OH)3] structural motif as a model for purple acid phosphatases

Herein, we describe the synthesis and X-ray structure of a new heteropentanuclear complex (2) containing a [Fe2 IIIZn3 II(μ-OH)3] structural unit and the unsymmetrical ligand H2L2-et. The molecular structure of (2) shows that it is formed by a basic dinuclear [FeIII(μ-OH)ZnII(L2-et)] unit that is connected to a second dinuclear [FeIII(μ-OH)ZnII(L2-et)] unit through a hydroxo bridge while a third Z

Impact of per-operative antibiotics on the urinary tract infection rate following mid-urethral sling surgery for urinary incontinence : a randomized controlled trial

Introduction and hypothesis: The objective was to compare the effect of antibiotics versus no antibiotics prophylaxis per-operatively on the frequency of urinary tract infection (UTI) following mid-urethral sling application to treat stress or mixed urinary incontinence. Methods: This study was designed as a multicenter prospective randomized trial. Women were included from eight centers in three

Comparison of inflammatory response and synovial metaplasia in immediate breast reconstruction with a synthetic and a biological mesh : a randomized controlled clinical trial

The aim of this study was to compare inflammatory response and synovial metaplasia in implant-based immediate breast reconstruction with a biological mesh (Veritas®) with that of a synthetic mesh (TIGR® Matrix Surgical Mesh). We hypothesize that the inflammatory response and formation of synovial metaplasia might be different and the rate of capsular contracture therefore different. The patients w

The value of complementary co-workers

As individuals specialize in specific knowledge areas, a society’s know-how becomes distributed across different workers. To use this distributed know-how, workers must be coordinated into teams that, collectively, can cover a wide range of expertise. This paper studies the interdependencies among co-workers that result from this process in a population-wide dataset covering educational specializa

The impact of tourism research

The exceedingly competitive climate of academia has increased the emphasis on performance-based research funding. In this paper we evaluate the UK's government assessment of research impact and critically comment upon the implications for future research conduct. The key findings are as follows; firstly we provide a summary of UK tourism research impact. Secondly, we demonstrate the effect of the

A Deep Learning Approach to MR-less Spatial Normalization for Tau PET Images

The procedure of aligning a positron emission tomography (PET) image with a common coordinate system, spatial normalization, typically demands a corresponding structural magnetic resonance (MR) image. However, MR imaging is not always available or feasible for the subject, which calls for enabling spatial normalization without MR, MR-less spatial normalization. In this work, we propose a template-

Young Somalis’ social identity in Sweden and Britain : The interplay of group dynamics, socio-political environments, and transnational ties in social identification processes

In this article, we aim to contribute to the literature on social identification among migrants and minorities by offering a theoretical framework that accounts for the interplay of socio-psychological factors, local and transnational group dynamics, and the socio-political environment in which migrants live. This approach enables us to analyse not only the political significance of identity, but