938 research outputs found

    Transformations of q-boson and q-fermion algebras

    Get PDF
    We investigate the algebras satisfied by q-deformed boson and fermion oscillators, in particular the transformations of the algebra from one form to another. Based on a specific algebra proposed in recent literature, we show that the algebra of deformed fermions can be transformed to that of undeformed standard fermions. Furthermore we also show that the algebra of q-deformed fermions can be transformed to that of undeformed standard bosons.Comment: 7 pages, RevTe

    Magnetic anomalies of offshore Krishna-Godavari basin, eastern continental margin of India

    Get PDF
    The marine magnetic data acquired from offshore Krishna-Godavari (K-G) basin, eastern continental margin of India (ECMI), brought out a prominent NE-SW trending feature, which could be explained by a buried structural high formed by volcanic activity. The magnetic anomaly feature is also associated with a distinct negative gravity anomaly similar to the one associated with 85°E Ridge. The gravity low could be attributed to a flexure at the Moho boundary, which could in turn be filled with the volcanic material. Inversion of the magnetic and gravity anomalies was also carried out to establish the similarity of anomalies of the two geological features (structural high on the margin and the 85°E Ridge) and their interpretations. In both cases, the magnetic anomalies were caused dominantly by the magnetization contrast between the volcanic material and the surrounding oceanic crust, whereas the low gravity anomalies are by the flexures of the order of 3-4 km at Moho boundary beneath them. The analysis suggests that both structural high present in offshore Krishna-Godavari basin and the 85°E Ridge have been emplaced on relatively older oceanic crust by a common volcanic process, but at discrete times, and that several of the gravity lows in the Bay of Bengal can be attributed to flexures on the Moho, each created due to the load of volcanic material

    Detailed Balance and Intermediate Statistics

    Full text link
    We present a theory of particles, obeying intermediate statistics ("anyons"), interpolating between Bosons and Fermions, based on the principle of Detailed Balance. It is demonstrated that the scattering probabilities of identical particles can be expressed in terms of the basic numbers, which arise naturally and logically in this theory. A transcendental equation determining the distribution function of anyons is obtained in terms of the statistics parameter, whose limiting values 0 and 1 correspond to Bosons and Fermions respectively. The distribution function is determined as a power series involving the Boltzmann factor and the statistics parameter and we also express the distribution function as an infinite continued fraction. The last form enables one to develop approximate forms for the distribution function, with the first approximant agreeing with our earlier investigation.Comment: 13 pages, RevTex, submitted for publication; added references; added sentence

    Phenotypic and Molecular Analysis of the Effect of 20-hydroxyecdysone on the Human Filarial Parasite Brugia malayi

    Get PDF
    A homologue of the ecdysone receptor has been identified and shown to be responsive to 20- hydroxyecdysone in Brugia malayi. However, the role of this master regulator of insect development has not been delineated in filarial nematodes. Gravid adult female B. malayi cultured in the presence of 20-hydroxyecdysone produced significantly more microfilariae and abortive immature progeny than control worms, implicating the ecdysone receptor in regulation of embryogenesis and microfilarial development. Transcriptome analyses identified 30 genes whose expression was significantly up-regulated in 20-hydroxyecdysone-treated parasites compared with untreated controls. Of these, 18% were identified to be regulating transcription. A comparative proteomic analysis revealed 932 proteins to be present in greater amounts in extracts of 20- hydroxyecdysone-treated adult females than in extracts prepared from worms cultured in the absence of the hormone. Of the proteins exhibiting a greater than two-fold difference in the 20- hydroxyecdysone-treated versus untreated parasite extracts, 16% were involved in transcriptional regulation. RNA interference (RNAi) phenotype analysis of Caenorhabditis elegans orthologs revealed that phenotypes involved in developmental processes associated with embryogenesis were significantly over-represented in the transcripts and proteins that were up-regulated by exposure to 20-hydroxyecdysone. Taken together, the transcriptomic, proteomic and phenotypic data suggest that the filarial ecdysone receptor may play a role analogous to that in insects, where it serves as a regulator of egg development

    Maximum gradient embeddings and monotone clustering

    Full text link
    Let (X,d_X) be an n-point metric space. We show that there exists a distribution D over non-contractive embeddings into trees f:X-->T such that for every x in X, the expectation with respect to D of the maximum over y in X of the ratio d_T(f(x),f(y)) / d_X(x,y) is at most C (log n)^2, where C is a universal constant. Conversely we show that the above quadratic dependence on log n cannot be improved in general. Such embeddings, which we call maximum gradient embeddings, yield a framework for the design of approximation algorithms for a wide range of clustering problems with monotone costs, including fault-tolerant versions of k-median and facility location.Comment: 25 pages, 2 figures. Final version, minor revision of the previous one. To appear in "Combinatorica

    Whole-Body Hypothermia, Cerebral Magnetic Resonance Biomarkers, and Outcomes in Neonates With Moderate or Severe Hypoxic-Ischemic Encephalopathy Born at Tertiary Care Centers vs Other Facilities: A Nested Study Within a Randomized Clinical Trial

    Get PDF
    IMPORTANCE: The association between place of birth and hypothermic neuroprotection after hypoxic-ischemic encephalopathy (HIE) in low- and middle-income countries (LMICs) is unknown. OBJECTIVE: To ascertain the association between place of birth and the efficacy of whole-body hypothermia for protection against brain injury measured by magnetic resonance (MR) biomarkers among neonates born at a tertiary care center (inborn) or other facilities (outborn). Design, Setting, and PARTICIPANTS: This nested cohort study within a randomized clinical trial involved neonates at 7 tertiary neonatal intensive care units in India, Sri Lanka, and Bangladesh between August 15, 2015, and February 15, 2019. A total of 408 neonates born at or after 36 weeks' gestation with moderate or severe HIE were randomized to receive whole-body hypothermia (reduction of rectal temperatures to between 33.0 °C and 34.0 °C; hypothermia group) for 72 hours or no whole-body hypothermia (rectal temperatures maintained between 36.0 °C and 37.0 °C; control group) within 6 hours of birth, with follow-up until September 27, 2020. Exposure: 3T MR imaging, MR spectroscopy, and diffusion tensor imaging. MAIN OUTCOMES AND MEASURES: Thalamic N-acetyl aspartate (NAA) mmol/kg wet weight, thalamic lactate to NAA peak area ratios, brain injury scores, and white matter fractional anisotropy at 1 to 2 weeks and death or moderate or severe disability at 18 to 22 months. RESULTS: Among 408 neonates, the mean (SD) gestational age was 38.7 (1.3) weeks; 267 (65.4%) were male. A total of 123 neonates were inborn and 285 were outborn. Inborn neonates were smaller (mean [SD], 2.8 [0.5] kg vs 2.9 [0.4] kg; P = .02), more likely to have instrumental or cesarean deliveries (43.1% vs 24.7%; P = .01), and more likely to be intubated at birth (78.9% vs 29.1%; P = .001) than outborn neonates, although the rate of severe HIE was not different (23.6% vs 17.9%; P = .22). Magnetic resonance data from 267 neonates (80 inborn and 187 outborn) were analyzed. In the hypothermia vs control groups, the mean (SD) thalamic NAA levels were 8.04 (1.98) vs 8.31 (1.13) among inborn neonates (odds ratio [OR], -0.28; 95% CI, -1.62 to 1.07; P = .68) and 8.03 (1.89) vs 7.99 (1.72) among outborn neonates (OR, 0.05; 95% CI, -0.62 to 0.71; P = .89); the median (IQR) thalamic lactate to NAA peak area ratios were 0.13 (0.10-0.20) vs 0.12 (0.09-0.18) among inborn neonates (OR, 1.02; 95% CI, 0.96-1.08; P = .59) and 0.14 (0.11-0.20) vs 0.14 (0.10-0.17) among outborn neonates (OR, 1.03; 95% CI, 0.98-1.09; P = .18). There was no difference in brain injury scores or white matter fractional anisotropy between the hypothermia and control groups among inborn or outborn neonates. Whole-body hypothermia was not associated with reductions in death or disability, either among 123 inborn neonates (hypothermia vs control group: 34 neonates [58.6%] vs 34 [56.7%]; risk ratio, 1.03; 95% CI, 0.76-1.41), or 285 outborn neonates (hypothermia vs control group: 64 neonates [46.7%] vs 60 [43.2%]; risk ratio, 1.08; 95% CI, 0.83-1.41). CONCLUSIONS AND RELEVANCE: In this nested cohort study, whole-body hypothermia was not associated with reductions in brain injury after HIE among neonates in South Asia, irrespective of place of birth. These findings do not support the use of whole-body hypothermia for HIE among neonates in LMICs. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02387385

    Ordered phase in the two-dimensional randomly coupled ferromagnet

    Full text link
    True ground states are evaluated for a 2d Ising model with random near neighbor interactions and ferromagnetic second neighbor interactions (the Randomly Coupled Ferromagnet). The spin glass stiffness exponent is positive when the absolute value of the random interaction is weaker than the ferromagnetic interaction. This result demonstrates that in this parameter domain the spin glass like ordering temperature is non-zero for these systems, in strong contrast to the 2d Edwards-Anderson spin glass.Comment: 7 pages; 9 figures; revtex; new version much extende

    Transcriptomic profile of adverse neurodevelopmental outcomes after neonatal encephalopathy

    Get PDF
    A rapid and early diagnostic test to identify the encephalopathic babies at risk of adverse outcome may accelerate the development of neuroprotectants. We examined if a whole blood transcriptomic signature measured soon after birth,predicts adverse neurodevelopmental outcomeeighteenmonths after neonatal encephalopathy.We performed next generation sequencing on whole blood ribonucleic acid obtained within sixhours of birth from the first 47encephalopathic babies recruited to the Hypothermia for Encephalopathy in Low and middle-income countries (HELIX)trial. Two infants with blood culture positive sepsis were excluded, and the data from remaining 45 were analysed. A total of 855genes were significantly differentially expressed between the good and adverse outcome groups, of which RGS1and SMC4 werethe most significant. Biological pathway analysis adjusted for gender, trial randomisation allocation (cooling therapy versus usual care) and estimated blood leukocyte proportions revealed over-representation of genes from pathways related to melatoninand polo-like kinase in babieswith adverse outcome. These preliminary data suggest that transcriptomic profiling may be a promising tool for rapid risk stratification in neonatal encephalopathy. It may provide insights into biological mechanismsand identify novel therapeutic targetsfor neuroprotection

    A bispecific diabody directed against prostate-specific membrane antigen and CD3 induces T-cell mediated lysis of prostate cancer cells

    Get PDF
    BACKGROUND: Although cancer of the prostate is one of the most commonly diagnosed cancers in men, no curative treatment currently exists after its progression beyond resectable boundaries. Therefore, new agents for targeted treatment strategies are needed. Cross-linking of tumor antigens with T-cell associated antigens by bispecific monoclonal antibodies have been shown to increase antigen-specific cytotoxicity in T-cells. Since the prostate-specific membrane antigen (PSMA) represents an excellent tumor target, immunotherapy with bispecific diabodies could be a promising novel treatment option for prostate cancer. METHODS: A heterodimeric diabody specific for human PSMA and the T-cell antigen CD3 was constructed from the DNA of anti-CD3 and anti-PSMA single chain Fv fragments (scFv). It was expressed in E. coli using a vector containing a bicistronic operon for co-secretion of the hybrid scFv V<sub>H</sub>CD3-V<sub>L</sub>PSMA and V<sub>H</sub>PSMA-V<sub>L</sub>CD3. The resulting PSMAxCD3 diabody was purified from the periplasmic extract by immobilized metal affinity chromatography (IMAC). The binding properties were tested on PSMA-expressing prostate cancer cells and PSMA-negative cell lines as well as on Jurkat cells by flow cytometry. For in vitro functional analysis, a cell viability test (WST) was used. For in vivo evaluation the diabody was applied together with human peripheral blood lymphocytes (PBL) in a C4-2 xenograft-SCID mouse model. RESULTS: By Blue Native gel electrophoresis, it could be shown that the PSMAxCD3 diabody is mainly a tetramer. Specific binding both to CD3-expressing Jurkat cells and PSMA-expressing C4-2 cells was shown by flow cytometry. In vitro, the diabody proved to be a potent agent for retargeting PBL to lyze C4-2 prostate cancer cells. Treatment of SCID mice inoculated with C4-2 tumor xenografts with the diabody and PBL efficiently inhibited tumor growth. CONCLUSIONS: The PSMAxCD3 diabody bears the potential for facilitating immunotherapy of prostate cancer and for the elimination of minimal residual disease
    • …
    corecore