Effects of Magnetic Field on Josephson Current in SNS System

The effect of a magnetic field on Josephson current has been studied for a superconductor/normal-metal/superconductor (SNS) system, where N is a two-dimensional electron gas in a confining potential. It is found that the dependence of Josephson currents on the magnetic field are sensitive to the width of the normal metal. If the normal metal is wide and contains many channels (subbands), the current on a weak magnetic field shows a dependence similar to a Fraunhofer-pattern in SIS system and, as the field gets strong, it shows another type of oscillatory dependence on the field resulting from the Aharonov-Bohm interference between the edge states. As the number of channels decreases (i.e. normal metal gets narrower), however, the dependence in the region of the weak field deviates from a clear Fraunhofer pattern and the amplitude of the oscillatory dependence in the region of the strong field is reduced.Comment: 14 pages, 9 figure

Electron spin-orbit splitting in InGaAs/InP quantum well studied by means of the weak antilocalization and spin-zero effects in tilted magnetic fields

The coupling between Zeeman spin splitting and Rashba spin-orbit terms has been studied experimentally in a gated InGaAs/InP quantum well structure by means of simultaneous measurements of the weak antilocalization (WAL) effect and beating in the SdH oscillations. The strength of the Zeeman splitting was regulated by tilting the magnetic field with the spin-zeros in the SdH oscillations, which are not always present, being enhanced by the tilt. In tilted fields the spin-orbit and Zeeman splittings are not additive, and a simple expression is given for the energy levels. The Rashba parameter and the electron g-factor were extracted from the position of the spin zeros in tilted fields. A good agreement is obtained for the spin-orbit coupling strength from the spin-zeros and weak antilocalization measurements.Comment: Accepted for publication in Semiconductors Science and Technolog

New skeletal tuberculosis cases in past populations from Western Hungary (Transdanubia)

The distribution, antiquity and epidemiology of tuberculosis (TB) have previously been studied in osteoarchaeological material in the eastern part of Hungary, mainly on the Great Plain. The purpose of this study is to map the occurrence of skeletal TB in different centuries in the western part of Hungary, Transdanubia, and to present new cases we have found. Palaeopathological analysis was carried out using macroscopic observation supported by radiographic and molecular methods. A large human osteoarchaeological sample (n = 5684) from Transdanubian archaeological sites ranging from the 2nd to the 18th centuries served as a source of material. Spinal TB was observed in seven individuals (in three specimens with Pott's disease two of which also had cold abscess) and hip TB was assumed in one case. The results of DNA for Mycobacterium tuberculosis were positive in seven of the eight cases identified by paleopathology, and negative in the assumed case of hip TB. However, the molecular results are consistent with highly fragmented DNA, which limited further analysis. Based on the present study and previously published cases, osteotuberculosis was found in Transdanubia mainly during the 9th–13th centuries. However, there are no signs of TB in many other 9th–13th century sites, even in those that lie geographically close to those where osteotuberculous cases were found. This may be due to a true absence of TB caused by the different living conditions, way of life, or origin of these populations. An alternative explanation is that TB was present in some individuals with no typical paleopathology, but that death occurred before skeletal morphological features could develop

Taxonomía de esponjas Poecillastra (Astrophorida: Pachastrellidae), con la descripción de tres nuevas especies batiales del Pacífico suroriental

Three new species of Poecillastra are described here from bathyal waters off central Chile. P. antonbruunae n. sp. is diagnosed by its two categories of oxeas, the smaller one only up to 621 μm in length, and calthrops as the sole triaene category; P. sinetridens n. sp. by the possession of oxeas larger than 3000 μm long, microxeas which can be over 300 μm long, and absence of triaenes; and P. maremontana n. sp. by its three categories of oxeas, three categories of streptasters (one of spirasters and two of plesiasters), one category of calthrops and centrotylote microxeas. Comments upon other Poecillastra and an identification key for Pacific species of the genus are given. Evolutionary hypotheses are discussed for the genus given the distribution of spicule morphotypes, as well as the recurrent phenomenon of spicule loss in Astrophorida. Five species of Pachastrella are transferred here to Poecillastra on the basis of their possession of microxeas instead of microrhabds, viz. P. cribrum Lebwohl, 1914; P. dilifera de Laubenfels, 1934 [sensu Dickinson (1945)]; P. fusca Lebwohl, 1914; P. incrustata Bergquist, 1968; and P. scrobiculosa Lebwohl, 1914. We recognize 28 species of Poecillastra, 19 of them occurring in the Pacific Ocean.El presente trabajo describe tres nuevas especies de Porifera del género Poecillastra, de aguas profundas de la región central de Chile. P. antonbruunae n. sp. presenta dos categorías de oxeas, la más pequeña solo hasta 621 μm de longitud y calthrops como la categoría única de trienios; P. sinetridens n. sp. posee oxeas de tamaño superior a 3000 μm de longitud, sus microxeas alcanzan un tamaño superior a 300 μm de longitud y los trienios están ausentes. P. maremontana n. sp. posee tres categorías de oxeas y tres de streptasters (una de spirasters y dos de plesiasters). Posee además una sola categoría de calthrops y microxeas centrotylotadas. En el presente trabajo se incluyen comentarios acerca de otras especies de Poecillastra, así como una clave de identificación del género para las especies del Pacífico. Se discuten también hipótesis evolutivas del género, basadas sobre la distribución de sus diferentes morfotipos espiculares, así como el fenómeno recurrente de la pérdida de espículas en el orden Astrophorida. Cinco especies del género Pachastrella fueron transferidas para Poecillastra en consecuencia de poseer micróxeas en vez de microrabdos, viz. P. cribrum Lebwohl, 1914; P. dilifera de Laubenfels de 1934 [sensu Dickinson (1945)]; P. fusca Lebwohl, 1914; P. incrustata Bergquist, 1968; y P. scrobiculosa Lebwohl de 1914. Actualmente consideramos válidas 28 especies de Poecillastra, 19 de ellas ocurren en el Océano Pacífico

Fast camera studies at an electron cyclotron resonance table plasma generator

A simple table-size ECR plasma generator operates in the ATOMKI without axial magnetic trap and without any particle extraction tool. Radial plasma confinement is ensured by a NdFeB hexapole. The table-top ECR is a simplified version of the 14 GHz ATOMKI-ECRIS. Plasma diagnostics experiments are planned to be performed at this device before installing the measurement setting at the big ECRIS. Recently, the plasma generator has been operated in pulsed RF mode in order to investigate the time evolution of the ECR plasma in two different ways. (1) The visible light radiation emitted by the plasma was investigated by the frames of a fast camera images with 1 ms temporal resolution. Since the visible light photographs are in strong correlation with the two-dimensional spatial distribution of the cold electron components of the plasma it can be important to understand better the transient processes just after the breakdown and just after the glow. (2) The time-resolved ion current on a specially shaped electrode was measured simultaneously in order to compare it with the visible light photographs. The response of the plasma was detected by changing some external setting parameters (gas pressure and microwave power) and was described in this paper

Women’s changing domestic responsibilities in neoliberal Africa: a relational time-space analysis of Lesotho’s garment industry

Since 2001 when Lesotho embraced the neoliberal African Growth and Opportunities Act that offers preferential access to the US market, its garment industry has expanded dramatically to become the nation’s leading employer. Elsewhere, large-scale employment of women in low-paid factory jobs has entailed spatial restructuring of gender and age relations. Lesotho is a distinctive context, with socio-spatial relations historically adjusted to male labour migration, high levels of contemporary male unemployment and alarming AIDS prevalence. Based on semi-structured interviews with 40 female factoryworkers and 37 dependents, this article applies a relational time-space analysis to explore how financial and spatio-temporal aspects of factory employment articulate to alter women’s relationships with those for whom they have culturally determined responsibilities: their children, those suffering from ill health and their (generally rural) home communities. The analysis highlights that such employment is not merely adding to women’s responsibilities, but transforming how they are able to undertake social reproduction, as practical, social and emotional roles are converted to largely financial obligations

Ascending aortic remodelling in Fabry disease after long-term enzyme replacement therapy.

Previous cross-sectional studies reported a high prevalence of ascending aorta dilations/aneurysms in male adults with Fabry disease, independently of cardiovascular risk factors. To characterise the remodelling of the ascending aorta in classic Fabry disease under long-term enzyme replacement therapy. Diameter of the ascending aorta was measured with magnetic resonance imaging at the sino-tubular junction (STJ), and proximal (pAsAo), and distal ascending aorta (dAsAo) at baseline, and after 5 and 10 years of enzyme replacement therapy in 15 adult Fabry patients (10 males; 5 females). Over a mean follow-up of 9.5 years, the annual expansion rates measured in 10 males with Fabry disease were 0.41 ± 0.16, 0.36 ± 0.25 and 0.41 ± 0.26 mm/y at the STJ, pAsAo and dAsAo, respectively. Expansion rate at the pAsAo level in male patients was significantly higher than the expected expansion projected from theoretical normal values: 0.36 ± 0.25 vs 0.13 ± 0.05, p = 0.017. In 5 females, the annual expansion rates at the STJ, pAsAo and dAsAo were 0.14 ± 0.11, 0.21 ± 0.18 and 0.26 ± 0.24 mm/y, respectively. There was no significant difference from the projected normal expansion rate at the level of the pAsAo: 0.21 ± 0.18 vs 0.13 ± 0.04, p = 0.39. Our data suggest that the remodelling of the ascending aorta is more pronounced in male patients with Fabry disease under long-term enzyme replacement therapy compared with the progression observed in a large population study