70 research outputs found
Search for Fingerprints of Tetrahedral Symmetry in
Theoretical predictions suggest the presence of tetrahedral symmetry as an
explanation for the vanishing intra-band E2-transitions at the bottom of the
odd-spin negative parity band in . The present study reports on
experiment performed to address this phenomenon. It allowed to determine the
intra-band E2 transitions and branching ratios B(E2)/B(E1) of two of the
negative-parity bands in .Comment: presented by Q.T. Doan at XLII Zakopane School of Physics: Breaking
Frontiers: Submicron Structures in Physics and Biology, May 2008. 5 pages,
minor corrections. To be published in the proceeding
How HIV/AIDS scale-up has impacted on non- HIV priority services in Zambia
Background: Much of the debate as to whether or not the scaling up of HIV service delivery in Africa benefits non-HIV priority services has focused on the use of nationally aggregated data. This paper analyses and presents routine health facility record data to show trend correlations across priority services. Methods: Review of district office and health facility client records for 39 health facilities in three districts of Zambia, covering four consecutive years (2004-07). Intra-facility analyses were conducted, service and coverage trends assessed and rank correlations between services measured to compare service trends within facilities. Results: VCT, ART and PMTCT client numbers and coverage levels increased rapidly. There were some strong positive correlations in trends within facilities between reproductive health services (family planning and antenatal care) and ART and PMTCT, with Spearman rank correlations ranging from 0.33 to 0.83. Childhood immunisation coverage also increased. Stock-outs of important drugs for non-HIV priority services were significantly more frequent than were stock-outs of antiretroviral drugs. Conclusions: The analysis shows scale-up in reproductive health service numbers in the same facilities where HIV services were scaling up. While district childhood immunisations increased overall, this did not necessarily occur in facility catchment areas where HIV service scale-up occurred. The paper demonstrates an approach for comparing correlation trends across different services, using routine health facility information. Larger samples and explanatory studies are needed to understand the client, facility and health systems factors that contribute to positive and negative synergies between priority services
Hierarchy of Hofstadter states and replica quantum Hall ferromagnetism in graphene superlattices
Self-similarity and fractals have fascinated researchers across various
disciplines. In graphene placed on boron nitride and subjected to a magnetic
field, self-similarity appears in the form of numerous replicas of the original
Dirac spectrum, and their quantization gives rise to a fractal pattern of
Landau levels, referred to as the Hofstadter butterfly. Here we employ
capacitance spectroscopy to probe directly the density of states (DoS) and
energy gaps in this spectrum. Without a magnetic field, replica spectra are
seen as pronounced DoS minima surrounded by van Hove singularities. The
Hofstadter butterfly shows up as recurring Landau fan diagrams in high fields.
Electron-electron interactions add another twist to the self-similar behaviour.
We observe suppression of quantum Hall ferromagnetism, a reverse Stoner
transition at commensurable fluxes and additional ferromagnetism within replica
spectra. The strength and variety of the interaction effects indicate a large
playground to study many-body physics in fractal Dirac systems.Comment: Nature Phys. (2014
Attenuation of Skeletal Muscle and Renal Injury to the Lower Limb following Ischemia-Reperfusion Using mPTP Inhibitor NIM-811.
INTRODUCTION: Operation on the infrarenal aorta and large arteries of the lower extremities may cause rhabdomyolysis of the skeletal muscle, which in turn may induce remote kidney injury. NIM-811 (N-metyl-4-isoleucine-cyclosporine) is a mitochondria specific drug, which can prevent ischemic-reperfusion (IR) injury, by inhibiting mitochondrial permeability transition pores (mPTP). OBJECTIVES: Our aim was to reduce damages in the skeletal muscle and the kidney after IR of the lower limb with NIM-811. MATERIALS AND METHODS: Wistar rats underwent 180 minutes of bilateral lower limb ischemia and 240 minutes of reperfusion. Four animal groups were formed called Sham (receiving vehicle and sham surgery), NIM-Sham (receiving NIM-811 and sham surgery), IR (receiving vehicle and surgery), and NIM-IR (receiving NIM-811 and surgery). Serum, urine and histological samples were taken at the end of reperfusion. NADH-tetrazolium staining, muscle Wet/Dry (W/D) ratio calculations, laser Doppler-flowmetry (LDF) and mean arterial pressure (MAP) monitoring were performed. Renal peroxynitrite concentration, serum TNF-alpha and IL-6 levels were measured. RESULTS: Less significant histopathological changes were observable in the NIM-IR group as compared with the IR group. Serum K+ and necroenzyme levels were significantly lower in the NIM-IR group than in the IR group (LDH: p<0.001; CK: p<0.001; K+: p = 0.017). Muscle mitochondrial viability proved to be significantly higher (p = 0.001) and renal function parameters were significantly better (creatinine: p = 0.016; FENa: p<0.001) in the NIM-IR group in comparison to the IR group. Serum TNF-alpha and IL-6 levels were significantly lower (TNF-alpha: p = 0.003, IL-6: p = 0.040) as well as W/D ratio and peroxynitrite concentration were significantly lower (p = 0.014; p<0.001) in the NIM-IR group than in the IR group. CONCLUSION: NIM-811 could have the potential of reducing rhabdomyolysis and impairment of the kidney after lower limb IR injury
Ischaemic conditioning and targeting reperfusion injury: a 30 year voyage of discovery
To commemorate the auspicious occasion of the 30th anniversary of IPC, leading pioneers in the field of cardioprotection gathered in Barcelona in May 2016 to review and discuss the history of IPC, its evolution to IPost and RIC, myocardial reperfusion injury as a therapeutic target, and future targets and strategies for cardioprotection. This article provides an overview of the major topics discussed at this special meeting and underscores the huge importance and impact, the discovery of IPC has made in the field of cardiovascular research
Overview of the impact of wood burning emissions on carbonaceous aerosols and PM in the Alpine region
International audienc
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