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Transient nucleation in selective laser melting of Zr-based bulk metallic glass

The crystallization rate during selective laser melting (SLM) of bulk metallic glasses (BMG) is a critical factor in maintaining the material's amorphous structure. To increase the understanding of the interplay between the SLM process and the crystallization behavior of BMGs, a numerical model based on the classical nucleation theory has been developed that accounts for the rapid temperature chan

Bibliographic analysis of the recent advancements in modeling and co-simulating the fifth-generation district heating and cooling systems

District heating and cooling systems have evolved through several development stages in order to improve their energy efficiency. The latest development reached the fifth generation where customers can be producers and/or consumers of thermal energy flows towards the network. The variety and complexity of system configurations and interactions between connected customers poses a challenge in adopt

Computer-assisted reading intervention for children with hearing impairment using cochlear implants : Effects on auditory event-related potentials and mismatch negativity

Objectives: The primary aim was to find out whether a computer-assisted reading intervention program with a phonic approach can affect event-related (ERPs) and mismatch negativity (MMN) in hearing impaired (HI) children using cochlear implants (CIs). Methods: This study involved a test group of 15 HI children with CIs and a control group of 14 normal hearing (NH) children. The children were 4 year

Phosphor thermometry for in-cylinder surface temperature measurements in diesel engines

Phosphor thermometry is a temperature measurement technique that has previously been employed in technically relevant applications to obtain surface temperature. The technique is based on temperature-dependent changes in a phosphor's luminescence. To improve the accuracy and precision of temperature measurements with this technique, the present study considers, by way of example, the impact of con

Differences in metal tolerance among strains, populations, and species of marine diatoms – Importance of exponential growth for quantification

Strains of microalgae vary in traits between species and populations due to adaptation or stochastic processes. Traits of individual strains may also vary depending on the acclimatization state and external forces, such as abiotic stress. In this study we tested how metal tolerance differs among marine diatoms at three organizational levels: species, populations, and strains. At the species level

Factors affecting DNA recovery from cartridge cases

Cartridge cases are often the sole items left behind after a shooting incident and DNA traces from these can identify persons connected to the shooting. However, the chance of retrieving usable DNA profiles from cartridge cases is limited, due to the low amounts of deposited DNA and subsequent DNA loss associated with the firing process. In the current study, we set out to increase the DNA recover

Holocene glacial history of Svalbard : Status, perspectives and challenges

We synthesize the current understanding of glacier activity on Svalbard from the end of the Late Pleistocene (12,000 yrs. before present) to the end of the Little Ice Age (c. 1920 AD). Our glacier history is derived from the SVALHOLA database, the first compilation of Holocene geochronology for Svalbard and the surrounding waters, including over 1,800 radiocarbon, terrestrial cosmogenic nuclide an

Serum Half-Lives for Short- and Long-Chain Perfluoroalkyl Acids after Ceasing Exposure from Drinking Water Contaminated by Firefighting Foam

BACKGROUND: Firefighting foam-contaminated ground water, which contains high levels of perfluoroalkyl substances (PFAS), is frequently found around airports. In 2018 it was detected that employees at a municipal airport in northern Sweden had been exposed to high levels of short-chain PFAS along with legacy PFAS (i.e., PFOA, PFHxS, and PFOS) through drinking water.OBJECTIVES: In this study, we aim

The need of latent variables for modelling decision-making in evacuation simulations

Evacuation models generally tend to make over-simplifications in the representation of human behaviour in fire due to the difficulties to capture its complexity. This work shows how ‘new’ discrete choice model approaches allow overcoming this issue. A description of the existing state-of-the-art of discrete choice models is introduced to highlight the potential of those models. Three case studies

Specialist Ambulance Nurses’ Perceptions of Nursing: A Phenomenographic Study

Although nursing is the main area of interest in the curriculum of the specialist ambulance nursing program in the advanced level of education, there has been reported a lack of knowledge about nursing in within the ambulance service. The aim was to explore specialist ambulance nurses’ perceptions of nursing, which were explored by employing a phenomenographic approach. The study comprises individ

Tensor-valued diffusion MRI differentiates cortex and white matter in malformations of cortical development associated with epilepsy

Objective: Delineation of malformations of cortical development (MCD) is central in presurgical evaluation of drug-resistant epilepsy. Delineation using magnetic resonance imaging (MRI) can be ambiguous, however, because the conventional T1- and T2-weighted contrasts depend strongly on myelin for differentiation of cortical tissue and white matter. Variations in myelin content within both cortex a

Anthropogenic transformation of Yangtze Plain freshwater lakes: patterns, drivers and impacts

Over the past half century, the Yangtze Plain of China has experienced rapid economic development. Lake reclamation (i.e., conversion of natural lake/wetland areas to agricultural/urban land or aquaculture, thereby reducing the area of natural waters) in particular has greatly contributed to meeting the increasing demands for food and urban development. However, until now, a comprehensive quantifi

Sintering of cBN Based Materials with a TaC Binder for Cutting Tool Application

Abstract: Ceramic matrix composites based on cubic boron nitride with a TaC binder phase are sintered under conditions of high pressure and high temperature. The sintering is carried out in a high-pressure apparatus of the toroid type in the temperature range of 1450–2450°C. It is shown that a chemical reaction between components of the mixture with the formation of TaB2 takes place at a sintering

Premature Termination of a Randomized Controlled Trial on Image-Guided Stereotactic Body Radiotherapy of Metastatic Spinal Cord Compression

Lessons Learned: It is possible to plan and treat some patients with stereotactic body radiotherapy (SBRT) in a timely fashion in an acute setting. Advanced and, in some indications, already implemented technologies such as SBRT are difficult to test in a randomized trial. Background: Stereotactic body radiotherapy (SBRT) in metastatic spinal cord compression (MSCC) could be an alternative to deco