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Pulsed magnetic flux compression power supplies for hypervelocity powder deposition
After reviewing the process of hypervelocity plasma deposition using augmented railgun technology, the paper presents several new concepts of pulsed rotating electric generators designed to power, on an almost continuous basis, the laboratory system designed and built at The University of Texas Center for Electromechanics (UT-CEM), which successfully validated the method and conducted proof-of-principle experiments. The two different rotating, repetitive pulsed power supplies described in the paper are: (1) an actively compensated flux compressor-alternator (actively compensated compulsator) and (2) a dc machine with series excitation, which so far did not have any application as a generator but proves, due to its self-excitation particularities, to be an almost ideal power source for the railgun. It needs to be emphasized that the augmented railgun and the actively and passively compensated compulsators represent almost mature technologies due to the continuous development of electromagnetic launch technology by the U.S. Department of Defense and especially by the U.S. Army – ready to be applied to many advanced civilian applications as it is the case with the hypervelocity powder railgun accelerators for surface conversion.Center for Electromechanic
ORIGIN OF LIGHT SCATTERING FROM DISORDERED SYSTEMS
Anelastic light scattering is computed numerically for model disordered
systems (linear chains and 2-dimensional site and bond percolators), with and
without electrical disorder. A detailed analysis of the vibrational modes and
of their Raman activity evidences that two extreme mechanisms for scattering
may be singled out. One of these resembles scattering from finite size systems,
while the other mechanisms originates from spatial fluctuations of the
polarizability and is such that modes in even small frequency intervals may
have very different Raman activities. As a consequence, the average coupling
coefficient is the variance of a zero-average quantity. Our
analysis shows that for both linear chains and 2-dimensional percolators the
second mechanism dominates over the first, and therefore Raman scattering from
disordered systems is essentially due to spatial fluctuations.Comment: 12 pages, Latex, 7 figures available on request
The Impact of the Global Financial Crisis and the Role of External and Internal Factors in Emerging Economies
This article assesses the impact of trade, capital openness and institutions on emerging economies’ output loss during the “Great Recession.” The fixed-effect estimates of an unbalanced panel of 122 emerging countries observed from 2008 to 2010 yield three main results. First, trade openness has exacerbated output loss. Second, capital openness can help mitigate the negative impact of an external shock, but this is conditional on the level of financial development. Finally, the results also point out that the interrelations between financial and institutional development affect the crisis’s severity
Acoustic Nature of the Boson Peak in Vitreous Silica
New temperature dependent inelastic x-ray (IXS) and Raman (RS) scattering
data are compared to each other and with existing inelastic neutron scattering
data in vitreous silica (v-SiO_2), in the 300 - 1775 K region. The IXS data
show collective propagating excitations up to Q=3.5 nm^-1. The temperature
behaviour of the excitations at Q=1.6 nm^-1 matches that of the boson peak
found in INS and RS. This supports the acoustic origin of the excess of
vibrational states giving rise to the boson peak in this glass.Comment: 10 pages and 4 figure
Transcriptional control of the B3GALT5 gene by a retroviral promoter and methylation of distant regulatory elements
We focused on transcription factors and epigenetic marks that regulate the B3GALT5 gene through its retroviral long terminal repeat (LTR) promoter. We compared the expression levels of the B3GALT5 LTR transcript, quantitated by competitive RT-PCR, with those of the candidate transcription factors HNF1\u3b1/\u3b2 and Cdx1/2, determined by Western blot analysis, in colon cancer biopsies, various cell lines, and cell models serving as controls. We found that HNF1\u3b1/\u3b2 were easily detected, irrespective of the amount of LTR transcript expressed by the source, whereas Cdx1/2 were undetectable, and no sample lacking HNF1\u3b1/\u3b2 expressed the LTR transcript. On transfection in proper host cells, both HNF1\u3b1 and HNF1\u3b2 provided detectable LTR transcript, whereas shRNA-mediated silencing of HNF1\u3b2 impaired transcription. Treating cells with 5\u2032-aza-2\u2032-deoxycytidine (5AZA) strongly reduced expression, without affecting HNF1\u3b1/\u3b2, despite the lack of CpG islands in the LTR and proximal sequences. By electrophoresis mobility shift and luciferase reporter assays, the LTR promoter binding and activity did not correlate with the amounts of LTR transcript expressed in the cells and depended on the levels of the transcription factors. We conclude that HNF1\u3b1/\u3b2 are necessary but insufficient to activate and regulate B3GALT5 LTR transcription, which depends on unknown regulatory elements that are active when methylated and located outside of and far from the LTR promoter
Total Hemi-overgrowth in Pigmentary Mosaicism of the (Hypomelanosis of) Ito Type: Eight Case Reports.
Pigmentary mosaicism of the (hypomelanosis of) Ito type is an umbrella term, which includes phenotypes characterized by mosaic hypopigmentation in the form of streaks, whorls, patchy, or more bizarre skin configurations (running along the lines of Blaschko): these cutaneous patterns can manifest as an isolated skin disorder (pigmentary mosaicism of the Ito type) or as a complex malformation syndrome in association with extracutaneous anomalies (most often of the musculoskeletal and/or nervous systems) (hypomelanosis of Ito). Affected individuals are anecdotally reported to have also partial or total body hemi-overgrowth (HOG), which often causes moderate to severe complications.We studied the occurrence and features of HOG in the 114 children and adults with mosaic pigmentary disorders of the Ito type diagnosed and followed up (from 2 to 22 years; average follow-up 16 years) at our Institutions.Eight patients (5 M, 3 F; aged 4 to 25 years; median age 16 years) out of the 114 analyzed (7%) fulfilled the criteria for unilateral HOG, with differences in diameter ranging from 0.4 to 4.0 cm (upper limbs) and 1.0 to 9.0 cm (lower limbs). Moreover, among these 8 patients, 5/8 filled in the 75th to 90th percentile for height; 6/8 had associated kyphoscoliosis; and 5/8 showed cognitive delays. No tumour complications were recorded. Overall, 6/8 HOG patients presented with additional (extracutaneous) syndromic manifestations, apart from the HOG (ie, with a clinical phenotype of hypomelanosis of Ito).The present study, which includes children and adults with the longest follow-up so far recorded, confirms the association between pigmentary mosaicism of the Ito type and HOG lowering previous estimates (7% vs 16%) for HOG in the context of mosaic hypopigmentation. A careful examination, looking at subtle to moderate asymmetries and associated complications within the spectrum of these mosaic pigmentary disorders, is recommended
Sequential adjuvant chemotherapy and radiotherapy in endometrial cancer--results from two randomised studies
INTRODUCTION: Endometrial cancer patients with high grade tumours, deep myometrial invasion or advanced stage disease have a poor prognosis. Randomised studies have demonstrated the prevention of loco-regional relapses with radiotherapy (RT) with no effect on overall survival (OS). The possible additive effect of chemotherapy (CT) remains unclear. Two randomised clinical trials (NSGO-EC-9501/EORTC-55991 and MaNGO ILIADE-III) were undertaken to clarify if sequential combination of chemotherapy and radiotherapy improves progression-free survival (PFS) in high-risk endometrial cancer. The two studies were pooled.
METHODS: Patients (n=540; 534 evaluable) with operated endometrial cancer International Federation of Obstetrics and Gynaecology (FIGO) stage I-III with no residual tumour and prognostic factors implying high-risk were randomly allocated to adjuvant radiotherapy with or without sequential chemotherapy.
RESULTS: In the NSGO/EORTC study, the combined modality treatment was associated with 36% reduction in the risk for relapse or death (hazard ratio (HR) 0.64, 95%confidence interval (CI) 0.41-0.99; P=0.04); two-sided tests were used. The result from the Gynaecologic Oncology group at the Mario Negri Institute (MaNGO)-study pointed in the same direction (HR 0.61), but was not significant. In the combined analysis, the estimate of risk for relapse or death was similar but with narrower confidence limits (HR 0.63, CI 0.44-0.89; P=0.009). Neither study showed significant differences in the overall survival. In the combined analysis, overall survival approached statistical significance (HR 0.69, CI 0.46-1.03; P=0.07) and cancer-specific survival (CSS) was significant (HR 0.55, CI 0.35-0.88; P=0.01).
CONCLUSION: Addition of adjuvant chemotherapy to radiation improves progression-free survival in operated endometrial cancer patients with no residual tumour and a high-risk profile. A remaining question for future studies is if addition of radiotherapy to chemotherapy improves the results
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