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Interface dynamics and crystal phase switching in GaAs nanowires

Controlled formation of non-equilibrium crystal structures is one of the most important challenges in crystal growth. Catalytically grown nanowires are ideal systems for studying the fundamental physics of phase selection, and could lead to new electronic applications based on the engineering of crystal phases. Here we image gallium arsenide (GaAs) nanowires during growth as they switch between ph

Characterization of total ecosystem-scale biogenic VOC exchange at a Mediterranean oak–hornbeam forest

Recently, the number and amount of biogenically emitted volatile organic compounds (VOCs) has been discussed in great detail. Depending on the ecosystem, the published number varies between a dozen and several hundred compounds. We present ecosystem exchange fluxes from a mixed oak–hornbeam forest in the Po Valley, Italy. The fluxes were measured by a proton transfer reaction-time-of-flight (PTR-T

Mass-flowering crops dilute pollinator abundance in agricultural landscapes across Europe

Mass-flowering crops (MFCs) are increasingly cultivated and might influence pollinator communities in MFC fields and nearby semi-natural habitats (SNHs). Across six European regions and 2 years, we assessed how landscape-scale cover of MFCs affected pollinator densities in 408 MFC fields and adjacent SNHs. In MFC fields, densities of bumblebees, solitary bees, managed honeybees and hoverflies were

Loss of genetic diversity and increased embryonic mortality in non-native lizard populations

Many populations are small and isolated with limited genetic variation and high risk of mating with close relatives. Inbreeding depression is suspected to contribute to extinction of wild populations, but the historical and demographic factors that contribute to reduced population viability are often difficult to tease apart. Replicated introduction events in non-native species can offer insights

Characterization and reconstruction of VOG noise with power spectral density analysis

Characterizing noise in eye movement data is important for data analysis, as well as for the comparison of research results across systems. We present a method that characterizes and reconstructs the noise in eye movement data from video-oculography (VOG) systems taking into account the uneven sampling in real recordings due to track loss and inherent system features. The proposed method extends t

Review on Dimensionless Numbers Relevant for Polymer Electrolyte Fuel Cells

With the concern about global warming, air pollution and energy security, the prospect of using polymer electrolyte fuel cells (PEFCs) in future sustainable and renewable energy conversion systems has achieved substantial momentum. Dimensionless numbers can be determined before construction of a model is started, to make simple estimations on the transport processes, for example, within the porous

Impact on Diffusion Parameters Computation in Gas Diffusion Layers, Considering the Land/Channel Region, Using the Lattice Boltzmann Method

Diffusion phenomena through the gas diffusion layer (GDL) at the microscale are one of the most complex physical phenomena to be described in proton exchange fuel cell (PEFC) numerical models. Predicting transport parameter behavior in GDLs is a valuable stage to propose micro-architectural designs, which can improve the efficiency and performance of fuel cells (FCs). The purpose of this paper is

The Image is Openness, The Practice is Data

The paper argues for the importance of seeing just how we conceptualise digital phenomena in relation to how the regulatory discourses. The Internet used to be an “information superhighway”, a “cyberspace”, or a “world wide web” often described as an empowering structure, that now has transformed to be understood in terms of “layers”, a generator of big data for a number of “platform” ventures and

Anion-exchange membranes with polycationic alkyl side chains attached via spacer units

Anion-exchange membrane (AEM) fuel cells are promising electrochemical systems for efficient and environmentally benign energy conversion. However, the development of high-performance fuel cells requires new AEMs tailored for high conductivity and chemical stability. Herein, we present the synthesis and characterization of AEMs with polycationic side chains attached to poly(phenylene oxide) (PPO)

Mid-Holocene humid periods reconstructed from calcite varves of the Lake Woserin sediment record (north-eastern Germany)

Time-series of varve properties and geochemistry were established from varved sediments of Lake Woserin (north-eastern Germany) covering the recent period AD 2010–1923 and the mid-Holocene time-window 6400–4950 varve years before present (vyr BP) using microfacies analyses, x-ray fluorescence (µ-XRF) scanning, microscopic varve chronology, and 14C dating. The microscopic varve chronology was compa

The Lund University Checklist for Incipient Exhaustion: a prospective validation of the onset of sustained stress and exhaustion warnings

BACKGROUND:The need for instruments that can assist in detecting the prodromal stages of stress-related exhaustion has been acknowledged. The aim of the present study was to evaluate whether the Lund University Checklist for Incipient Exhaustion (LUCIE) could accurately and prospectively detect the onset of incipient exhaustion and to what extent work stressor exposure and private burdens were ass

“And how old are you?”: Age reference as an interpretative device in radio counselling

Aim of study: Negotiations about problem definitions are a crucial part of psychotherapeutic and counselling work. In a conversation with a psychotherapist or a counsellor, the client's initial description of his or her trouble is transformed into an expert-informed problem formulation. This study aims to explicate how reasoning about troubles and life difficulties in a dialogue with a psychothera

Will I fit in and do well? The importance of social belongingness and self-efficacy for explaining gender differences in interest in STEM- and HEED-majors.

Throughout the world, the labor market is clearly gender segregated. More research is needed to explain women's lower interest in STEM (Science, Technology, Engineering and Mathematics) majors and particularly to explain men's lower interest in HEED (Health care, Elementary Education, and the Domestic spheres) majors. We tested self-efficacy (competence beliefs) and social belongingness expectatio

Using Satellite Data on Nighttime Lights Intensity to Estimate Contemporary Human Migration Distances

For well over a century, migration researchers have recognized the lack of adequate distance measures to be a key obstacle for advancing understanding of internal migration. The problem arises from the convention of spatially defining migration as the crossing of administrative borders. Since administrative regions vary in size, shape, and settlement patterns, it is difficult to tell how far moverFor well over a century, migration researchers have recognized the lack of adequate distance measures to be a key obstacle for advancing understanding of internal migration. The problem arises from the convention of spatially defining migration as the crossing of administrative borders. Because administrative regions vary in size, shape, and settlement patterns, it is difficult to tell how far mov

Role of hydrological studies for the development of the TDPS system

The South American Altiplano in the Andes is, aside from Tibet, the most extensive high plateau on Earth. This semiarid area represents important water resources storages, including the Lakes Titicaca and Poopó located in the northern and central Altiplano, respectively. The two lake basins and the southern saltpans constitute a large watershed, called the Lake Titicaca, Desaguadero River, Lake Po

Assessing uncertainties in land cover projections

Understanding uncertainties in land cover projections is critical to investigating land-based climate mitigation policies, assessing the potential of climate adaptation strategies and quantifying the impacts of land cover change on the climate system. Here, we identify and quantify uncertainties in global and European land cover projections over a diverse range of model types and scenarios, extend