Negative Domain Wall Contribution to the Resistivity of Microfabricated Fe Wires

The effect of domain walls on electron transport has been investigated in microfabricated Fe wires (0.65 to 20 $\mu m$ linewidths) with controlled stripe domains. Magnetoresistance (MR) measurements as a function of domain wall density, temperature and the angle of the applied field are used to determine the low field MR contributions due to conventional sources in ferromagnetic materials and that due to the erasure of domain walls. A negative domain wall contribution to the resistivity is found. This result is discussed in light of a recent theoretical study of the effect of domain walls on quantum transport.Comment: 7 pages, 4 postscript figures and 1 jpg image (Fig. 1

Silicon spin diffusion transistor: materials, physics and device characteristics

The realisation that eaveryday electronics has ignored the spin of the carrier in favour of its charge is the foundation of the field of spintronics. Starting with simple two-terminal devices based on GMR and tunnel magnetoresistance, the technology has advanced to consider three-terminal devices that aim to combine spin sensitivity with a high current gain and a large current output. These devices require both efficient spin injection and semiconductor fabrication. In this paper, a discussion is presented of the design, operation and characteristics of the only spin transistor that has yielded a current gain greater than one in combination with reasonable output current

Post-mortem computed tomography is a useful tool for determining the pulmonary ventilation status in newborns

<jats:title>Abstract</jats:title><jats:sec> <jats:title>Introduction</jats:title> <jats:p>Lung ventilation is a standard sign of life in newborns. Post-mortem computed tomography (PMCT) is highly sensitive to the presence of gas in the body including the lungs. Current standard examinations to determine the pulmonary ventilation status in newborns are the flotation test and histology. The purpose of this study was to compare the accuracy of PMCT with the flotation test for determining the lung ventilation status with histological control as reference standard. A cut-off value as CT number in Hounsfield Units (HU) determining lung ventilation of newborns in PMCT should be established.</jats:p> </jats:sec><jats:sec> <jats:title>Methods</jats:title> <jats:p>A total of 38 infant lungs were examined of which 21 lungs were from infants deceased shortly after live birth (control group) and 17 lungs belonged to infants where live birth was in question (study group). All lungs were examined using PMCT, flotation test, and histological examination.</jats:p> </jats:sec><jats:sec> <jats:title>Results</jats:title> <jats:p>The control group showed an overall mean attenuation ± standard deviation of −219 HU ± 135; the study group of 45 ± 15 HU in histologically nonventilated lungs versus −192 ± 207 HU; (<jats:italic>p</jats:italic> < 0.001) in ventilated lungs. The best cut-off value for optimal discrimination of ventilated and nonventilated lungs in newborns was −35 mean HU.</jats:p> </jats:sec><jats:sec> <jats:title>Conclusion</jats:title> <jats:p>PMCT is equally well suited to determine lung ventilation as the flotation test. It provides additional information regarding pulmonary infiltration, degree of putrefaction, or signs of trauma (fractures, pneumothorax). Histology remains mandatory in ambiguous cases.</jats:p> </jats:sec&gt

Recent cross-section measurements of neutron-induced reactions of importance for background estimates in 0νββ

We report on cross-section measurements for the reactions 76Ge(n,2n)75Ge, 76Ge(n,n′γ)76Ge, 126,127,128Te(n,γ)127,129,131Te, and 136Xe(n,n′γ)136Xe in the neutron energy range between 0.5 MeV and 15 MeV

Towards a More Complete and Accurate Experimental Nuclear Reaction Data Library (EXFOR): International Collaboration Between Nuclear Reaction Data Centres (NRDC)

The International Network of Nuclear Reaction Data Centres (NRDC) coordinated by the IAEA Nuclear Data Section (NDS) is successfully collaborating in the maintenance and development of the EXFOR library. As the scope of published data expands (e.g., to higher energy, to heavier projectile) to meet the needs from the frontier of sciences and applications, it becomes nowadays a hard and challenging task to maintain both completeness and accuracy of the whole EXFOR library. The paper describes evolution of the library with highlights on recent developments.Comment: 4 pages, 2 figure

Analysis of Antibody and Cytokine Markers for Leprosy Nerve Damage and Reactions in the INFIR Cohort in India

Leprosy is one of the oldest known diseases. In spite of the established fact that it is least infectious and a completely curable disease, the social stigma associated with it still lingers in many countries and remains a major obstacle to self reporting and early treatment. The nerve damage that occurs in leprosy is the most serious aspect of this disease as nerve damage leads to progressive impairment and disability. It is important to identify markers of nerve damage so that preventive measures can be taken. This prospective cohort study was designed to look at the potential association of some serological markers with reactions and nerve function impairment. Three hundred and three newly diagnosed patients from north India were recruited for this study. The study attempts to reflect a model of nerve damage initiated by mycobacterial antigens and maintained by ongoing inflammation through cytokines such as Tumour Necrosis Factor alpha and perhaps extended by antibodies against nerve components

A Systematic Review of Immunological Studies of Erythema Nodosum Leprosum.

Erythema nodosum leprosum (ENL) is a painful inflammatory complication of leprosy occurring in 50% of lepromatous leprosy patients and 5-10% of borderline lepromatous patients. It is a significant cause of economic hardship, morbidity and mortality in leprosy patients. Our understanding of the causes of ENL is limited. We performed a systematic review of the published literature and critically evaluated the evidence for the role of neutrophils, immune complexes (ICs), T-cells, cytokines, and other immunological factors that could contribute to the development of ENL. Searches of the literature were performed in PubMed. Studies, independent of published date, using samples from patients with ENL were included. The search revealed more than 20,000 articles of which 146 eligible studies were included in this systematic review. The studies demonstrate that ENL may be associated with a neutrophilic infiltrate, but it is not clear whether it is an IC-mediated process or that the presence of ICs is an epiphenomenon. Increased levels of tumor necrosis factor-α and other pro-inflammatory cytokines support the role of this cytokine in the inflammatory phase of ENL but not necessarily the initiation. T-cell subsets appear to be important in ENL since multiple studies report an increased CD4+/CD8+ ratio in both skin and peripheral blood of patients with ENL. Microarray data have identified new molecules and whole pathophysiological pathways associated with ENL and provides new insights into the pathogenesis of ENL. Studies of ENL are often difficult to compare due to a lack of case definitions, treatment status, and timing of sampling as well as the use of different laboratory techniques. A standardized approach to some of these issues would be useful. ENL appears to be a complex interaction of various aspects of the immune system. Rigorous clinical descriptions of well-defined cohorts of patients and a systems biology approach using available technologies such as genomics, epigenomics, transcriptomics, and proteomics could yield greater understanding of the condition