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Exploiting Flexible Memristors Based on Solution-Processed Colloidal CuInSe2 Nanocrystals

Compared to analogous bulk materials, colloidal nanocrystals have presented a powerful platform for building up electronic devices on the nano/micrometer scale and flexible portable electronic apparatus with the benefits of solution-based processing approach at room temperature. Herein, memristors based on CuInSe2 (CISe) colloidal nanocrystals prepared using a solution-based process at room temper

Managing an altered social context—Patients experiences of staying away from home while undergoing proton beam therapy

Aim: To illuminate the experience of an altered social context for patients with primary brain tumours living away from home while undergoing proton beam therapy. Design: A descriptive, qualitative cross-sectional interview study. Methods: Nineteen patients were interviewed between December 2015–August 2016, either during (N = 7) or before and after (N = 12) their proton beam therapy. A hermeneuti

The HepMC3 event record library for Monte Carlo event generators

In high-energy physics, Monte Carlo event generators (MCEGs) are used to simulate the interactions of high energy particles. MCEG event records store the information on the simulated particles and their relationships, and thus reflect the simulated evolution of physics phenomena in each collision event. We present the HepMC3 library, a next-generation framework for MCEG event record encoding and m

Bureaucracy and Growth

We revisit the hypothesis that a Weberian bureaucracy enhances economic growth. Theoretically, we develop arguments for why such a bureaucracy may enhance growth and discuss plausible counterarguments. Empirically, we use new measures capturing various Weberian features in countries across the world, with some time series extending back to 1789. The evidence base from previous large-N studies is s

Staying or leaving? The effects of university availability on educational choices and rural depopulation

Universities are often viewed as engines of local economic growth that could mitigate rural depopulation. However, university studies might make individuals more prone to move. We explore this issue in a quasi-experiment arising due to a sudden reduction in the number of student places at a regional university in northern Sweden in 1998. We find that the reduction in student places affected both e

QF Modelling of Electro-Pulse-Therapy

Vid elektro-pulsbehandling svarar omedelbart bara de celler som utsätts för ett tillräckligt starkt elektriskt fält. De tumörceller som permeabiliseras blir mycket mer tillgängliga för hydrofila molekyler eftersom dessa normalt avvisas av membranbarriären. Anticancermedlet Bleomycin har visat sig vara det mest potenta läkemedlet i elektropulsbehandling och är det som ofta används i elektro-puls-keIn electro-pulse therapy treatment, only the cells exposed to a sufficiently strong electric field will respond immediately. The tumour cells that are permeabilized become much more accessible to hydrophilic molecules since these are normally rejected by the membrane barrier. The anticancer agent Bleomycin has proven to be the most potent drug in electro-pulse therapy and is the one often used in

Exposure to radiation from global system for mobile communications at 1,800 MHz significantly changes gene expression in rat hippocampus and cortex

We have earlier shown that radio frequency electromagnetic fields can cause significant leakage of albumin through the blood-brain barrier of exposed rats as compared to non-exposed rats, and also significant neuronal damage in rat brains several weeks after a 2 h exposure to a mobile phone, at 915 MHz with a global system for mobile communications (GSM) frequency modulation, at whole-body specifi

Polonium-210 in the bio-sphere : Bio-kinetics and biological effects

Polonium-210 is an alpha particle emitting radioactive element with a half-life of 138 days. It appears at the end of the decay-chain of Uranium-238 where the long lived Lead-210 (22.3 a) decays to Bismuth-210, and finally Polonium-210. 210Po is introduced into the biosphere through various routes of terrestrial and marine radioecological pathways. The level of 210Po activity in drinking water (5

Nonthermal GSM RF and ELF EMF effects upon rat BBB permeability

Since the late 1980s, our group has examined the effects of radiofrequency electromagnetic fields (RF-EMF), including pulse-modulated waves of the type emitted by mobile phones, upon the blood-brain barrier. In more than 2,000 rats, we have repeatedly demonstrated a passage of the rats' own albumin from the blood through the brain capillaries into the surrounding brain parenchyma at SAR values dow

Non-thermal effects of EMF upon the mammalian brain : The Lund experience

The environment in which biology exists has dramatically changed during the last decades. Life was formed during billions of years, exposed to, and shaped by the original physical forces such as gravitation, cosmic irradiation and the terrestrial magnetism. The existing organisms are created to function in harmony with these forces. However, in the late 19th century mankind introduced the use of e

Effects of microwaves from GSM mobile phones on the blood-brain barrier and neurons in rat brain

Our group has since 1988 studied the effects of different intensities and modulations of 915MHz RF in a rat model where the exposure takes place in a TEM-cell during various time periods and post exposure recovery times. The power fed into TEM-cells was 0.125, 1.25, 12.5 or 125mW corresponding to whole body SAR (determined experimentally): 0.2, 2, 20 or 200mW/kg. The rats were awake and not restra

An electrical impedance indicator to assess electropermeabilisation in tissue, a preliminary study

A controlled pulsed electrical field applied to a living tissue is believed to cause a structural reorganisation in the lipid bilayer of the cell membranes. This electropermeabilisation or electroporation process is used for opening up the cell membrane in order to get access to the cell. An electrical impedance tissue model that incorporates electroporation is presented. From this model a bio-imp

A Model for Evaluating Therapeutic Response of Combined Cancer Treatment Modalities : Applied to Treatment of Subcutaneously Implanted Brain Tumors (N32 and N29) in Fischer Rats with Pulsed Electric Fields (PEF) and 60Co-gamma Radiation (RT)

The aim of the present study is to develop a mathematical model for evaluating therapeutic response of combined treatment modalities. The study was performed in rats of the Fischer-344 strain with rat glioma N32 or N29 tumors implanted subcutaneously on the thigh of the hind leg. Pulsed electric fields, PEF, with 16 exponentially decaying pulses with a maximum electric field strength of 140 V/mm a

The effect of the Siberian tundra on the environment of the shelf seas and the Arctic Ocean

The Tundra Ecology -94 expedition investigated inflow of inorganic and organic carbon to the shelf seas by river runoff, and its transformation by biochemical processes in seawater and sediment. In addition, anthropogenic radionuclides, 137Cs, 90Sr, and 239,240Pu, were studied in water and sediments. The distribution of dissolved inorganic carbon indicates that the majority of the Ob and Yenisey d

Finite element analysis for simplified thermal dose planning in interstitial laser thermotherapy

The objective was to investigate if diffusing laser fibres can be modelled as conductive heat sources without miscalculating coagulated volumes, and if finite element analysis, disregarding light transport, may be used for three dimensional (3D) treatment planning in interstitial laser thermotherapy (ILT). Temperature distributions and coagulated volumes with a diffusing laser fibre, as compared t

Effect of high voltage electrical pulses on subcutaneous glioma tumours on rats

The antitumour effect of applied high voltage exponential pulses was investigated on rats with subcutaneously implanted N32 brain tumours. Superficial tumours on the thigh were produced by the injection of 100 000 N32 glioma cells on Fischer-344 rats. Four weeks after inoculation, a solid tumour has grown to a size of about 1 cm located directly under the skin. Short electric high voltage pulses w

In vivo evaluation of femoral blood flow measured with magnetic resonance

Quantitative measurements of blood flow based on magnetic resonance imaging (MRI) using conventional multiple spin echo sequences were evalutated in vivo in healthy young volunteers. Blood flow was measured using MRI in the femoral vein. The initial slope of the multiple spin echo decay curve, corrected for the T2 decay of non-flowing blood was used to calculate the blood flow. As a reference, the

Magnetic resonance imaging and aneurysm clips. Magnetic properties and image artifacts

The magnetic properties of 12 different types of aneurysm clip were investigated in order to identify which clips allow postoperative magnetic resonance (MR) imaging without risk. Clip-induced MR artifacts were also quantitatively studied using a geometrical phantom. Nonferromagnetic aneurysm clips like the Yasargil Phynox, Sugita Elgiloy, and Vari-Angle McFadden clips do not appear to contraindic