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Thermometry by micro and nanodevices

In this paper we briefly discuss the current provisional temperature scale of 2000 (PLTS-2000) for low temperatures. Electronic thermometry is presented and discussed, focusing on its potential in verifying and realizing a future temperature scale. The discussion covers secondary thermometers such as NIS and SIS thermometers and noise, shot noise and Coulomb blockade primary thermometers. The last

Influence of environment on tunneling thermometry

The electromagnetic environment of a tunnel junction can influence significantly the tunneling characteristics. We investigate experimentally a particular environment formed by tunnel junctions and compare the results with a theoretical model. We discuss Single Junction Thermometer and a two junction Coulomb Blockade Thermometer as examples.

Primary tunnel junction thermometry

We describe the concept and experimental demonstration of primary thermometry based on a four-probe measurement of a single tunnel junction embedded within four arrays of junctions. We show that in this configuration random sample specific and environment-related errors can be avoided. This method relates temperature directly to Boltzmann constant, which will form the basis of the definition of te

Double oxidation scheme for tunnel junction fabrication

The authors report a method to achieve Al-Al Ox -Al tunnel junctions with high specific resistance in a controlled manner using a double oxidation technique. The technique is based on the standard method for oxidation repeated on an additional Al layer. The tunnel junctions were characterized with standard methods, such as comparison of room temperature resistance with liquid helium resistance and

High-resolution superconducting single-flux quantum comparator for sub-Kelvin temperatures

A design of sub-Kelvin single-flux quantum (SFQ) circuits with reduced power dissipation and additional cooling of shunt resistors has been developed and characterized. The authors demonstrate operation of SFQ comparators with current resolution of 40 nA at 2 GHz sampling rate. Due to improved cooling the electron temperature in shunt resistors of a SFQ comparator is below 50 mK when the bath temp

Dual pass electron beam writing of bit arrays with sub-100 nm bits on imprint lithography masters for patterned media production

A model and experimental results of a new method for exposing bit arrays with electron beam lithography are presented. The method allows the reduction of the amount of pattern data by orders of magnitude. The method utilises two overlapped exposures. In the first exposure a 1-D array of parallel stripes is written and in the second exposure another 1-D array of parallel stripes orthogonal to the f

Underwater Terrain Navigation Using Standard Sea Charts and Magnetic Field Maps

Many ships today rely on Global Navigation Satellite Systems (GNSS), for their navigation, where GPS (Global Positioning System) is the most well-known. Unfortunately, the GNSS systems make the ships dependent on external systems, which can be malfunctioning, be jammed or be spoofed. There are today some proposed techniques where, e.g., bottom depth measurements are compared with known maps using

Histological improvement of liver fibrosis in well-treated patients with autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic autoimmune liver disease that if left untreated may lead to the development of cirrhosis. Previous studies on AIH patients have suggested that fibrosis and even cirrhosis can be reversed by medical treatment. The aim of this study was to evaluate the efficacy of medical treatment for protection of developing fibrosis and cirrhosis. A total of 258 liver biops

Effectiveness of digital breast tomosynthesis (3D-mammography) in population breast cancer screening : A protocol for a collaborative individual participant data (IPD) meta-analysis

Background: There is accumulating evidence that digital breast tomosynthesis, referred to as 3D-mammography in this protocol, improves screen-detection measures compared to standard 2D-mammography in the context of population screening for breast cancer. However, the effect of 3D-mammography at follow-up of screened women is not yet known: it is unknown whether additional cancer detection from 3D-

Genomic correlates of glatiramer acetate adverse cardiovascular effects lead to a novel locus mediating coronary risk

Glatiramer acetate is used therapeutically in multiple sclerosis but also known for adverse effects including elevated coronary artery disease (CAD) risk. The mechanisms underlying the cardiovascular side effects of the medication are unclear. Here, we made use of the chromosomal variation in the genes that are known to be affected by glatiramer treatment. Focusing on genes and gene products repor

Recent Advances in Cardiovascular Magnetic Resonance

Cardiovascular magnetic resonance imaging has become the gold standard for evaluating myocardial function, volumes, and scarring. Additionally, cardiovascular magnetic resonance imaging is unique in its comprehensive tissue characterization, including assessment of myocardial edema, myocardial siderosis, myocardial perfusion, and diffuse myocardial fibrosis. Cardiovascular magnetic resonance imagi

Travel abroad increases sexual health risk-taking among Swedish youth : A population-based study using a case-crossover strategy

Background: The fact that youth take sexual risks when they are abroad have been shown in previous studies. However, it is not known if they increased their sexual risk-taking when travelling abroad, compared to the stay in their homeland. Objective: To assess whether Swedish youth increased their individual sexual risk behaviour, defined as having a casual sex partner, when travelling abroad and

A generation at risk : A cross-sectional study on HIV/AIDS knowledge, exposure to mass media, and stigmatizing behaviors among young women aged 15–24 years in Ghana

HIV/AIDS stigmatizing behaviors are a huge barrier to early detection and treatment of individuals with the AIDS virus. HIV/AIDS stigma and related consequences are debilitating, especially for vulnerable populations. This study sought to assess whether young women's HIV/AIDS knowledge levels and exposure to mass media (television and radio) have an influence on their stigmatizing behaviors and ro

Effectiveness of antenatal care services in reducing neonatal mortality in Kenya : Analysis of national survey data

Background: Although global neonatal mortality declined by about 40 percent from 1990 to 2013, it still accounted for about 2.6 million deaths globally and constituted 42 percent of global under-five deaths. Most of these deaths occur in developing countries. Antenatal care (ANC) is a globally recommended strategy used to prevent neonatal deaths. In Kenya, over 90 percent of pregnant women attend