288 research outputs found

    One-way multigrid method in electronic structure calculations

    Get PDF
    We propose a simple and efficient one-way multigrid method for self-consistent electronic structure calculations based on iterative diagonalization. Total energy calculations are performed on several different levels of grids starting from the coarsest grid, with wave functions transferred to each finer level. The only changes compared to a single grid calculation are interpolation and orthonormalization steps outside the original total energy calculation and required only for transferring between grids. This feature results in a minimal amount of code change, and enables us to employ a sophisticated interpolation method and noninteger ratio of grid spacings. Calculations employing a preconditioned conjugate gradient method are presented for two examples, a quantum dot and a charged molecular system. Use of three grid levels with grid spacings 2h, 1.5h, and h decreases the computer time by about a factor of 5 compared to single level calculations.Comment: 10 pages, 2 figures, to appear in Phys. Rev. B, Rapid Communication

    Josephson dynamics for coupled polariton modes under the atom-field interaction in the cavity

    Full text link
    We consider a new approach to the problem of Bose-Einstein condensation (BEC) of polaritons for atom-field interaction under the strong coupling regime in the cavity. We investigate the dynamics of two macroscopically populated polariton modes corresponding to the upper and lower branch energy states coupled via Kerr-like nonlinearity of atomic medium. We found out the dispersion relations for new type of collective excitations in the system under consideration. Various temporal regimes like linear (nonlinear) Josephson transition and/or Rabi oscillations, macroscopic quantum self-trapping (MQST) dynamics for population imbalance of polariton modes are predicted. We also examine the switching properties for time-averaged population imbalance depending on initial conditions, effective nonlinear parameter of atomic medium and kinetic energy of low-branch polaritons.Comment: 10 pages, 6 postscript figures, uses svjour.cl

    Mott Transition in Degenerate Hubbard Models: Application to Doped Fullerenes

    Full text link
    The Mott-Hubbard transition is studied for a Hubbard model with orbital degeneracy N, using a diffusion Monte-Carlo method. Based on general arguments, we conjecture that the Mott-Hubbard transition takes place for U/W \propto \sqrt{N}, where U is the Coulomb interaction and W is the band width. This is supported by exact diagonalization and Monte-Carlo calculations. Realistic parameters for the doped fullerenes lead to the conclusion that stoichiometric A_3 C_60 (A=K, Rb) are near the Mott-Hubbard transition, in a correlated metallic state.Comment: 4 pages, revtex, 1 eps figure included, to be published in Phys.Rev.B Rapid Com

    Progress towards malaria control targets in relation to national malaria programme funding

    Get PDF
    Background: Malaria control has been dramatically scaled up the past decade, mainly thanks to increasing international donor financing since 2003. This study assessed progress up to 2010 towards global malaria impact targets, in relation to Global Fund, other donor and domestic malaria programme financing over 2003 to 2009. Methods. Assessments used domestic malaria financing reported by national programmes, and Global Fund/OECD data on donor financing for 90 endemic low- and middle-income countries, WHO estimates of households owning one or more insecticide-treated mosquito net (ITN) for countries in sub-Saharan Africa, and WHO-estimated malaria case incidence and deaths in countries outside sub-Saharan Africa. Results: Global Fund and other donor funding is concentrated in a subset of the highest endemic African countries. Outside Africa, donor funding is concentrated in those countries with highest malaria mortality and case incidence rates over the years 2000 to 2003. ITN coverage in 2010 in Africa, and declines in case and death rates per person at risk over 2004 to 2010 outside Africa, were greatest in countries with highest donor funding per person at risk, and smallest in countries with lowest donor malaria funding per person at risk. Outside Africa, all-source malaria programme funding over 2003 to 2009 per case averted (565,749)orperdeathaverted(56-5,749) or per death averted (58,000-3,900,000) over 2004 to 2010 tended to be lower (more favourable) in countries with higher donor malaria funding per person at risk. Conclusions: Increases in malaria programme funding are associated with accelerated progress towards malaria control targets. Associations between programme funding per person at risk and ITN coverage increases and declines in case and death rates suggest opportunities to maximize the impact of donor funding, by strategic re-allocation to countries with highest continued need

    “I Was Raised in Addiction”: Constructions of the Self and the Other in Discourses of Addiction and Recovery

    Get PDF
    The aim of this article is to address how conceptualizations of addiction shape the lived experiences of people who use drugs (PWUDs) during the current opioid epidemic. Using a discourse analytic approach, we examine interview transcripts from 27 PWUDs in rural Appalachian Ohio. We investigate the ways in which participants talk about their substance use, what these linguistic choices reveal about their conceptions of self and other PWUDs, and how participants’ discursive caches might be constrained by or defined within broader social discourses. We highlight three subject positions enacted by participants during the interviews: addict as victim of circumstance, addict as good Samaritan, and addict as motivated for change. We argue participants leverage these positions to contrast themselves with a reified addict-other whose identity carries socially ascribed characteristics of being blameworthy, immoral, callous, and complicit. We implicate these processes in the perpetuation of intragroup stigma and discuss implications for intervention

    Susceptibility to non-tuberculous mycobacterial disease is influenced by rs1518111 in IL10

    Get PDF
    Although exposure to potentially pathogenic nontuberculous mycobacteria (NTM) via soil and domestic water supplies is common, pulmonary infection and disease are confined to a small proportion of older individuals. Previously, alleles of a polymorphism in IL10 (rs1800896) were associated with NTM disease and we demonstrated elevated production of IL-10 by blood leukocytes from patients with pulmonary NTM. Here seven additional polymorphisms in IL10 were investigated in a larger cohort of Caucasian controls and patients with pulmonary NTM disease. This demonstrated a significant association between pulmonary NTM disease and one polymorphism (rs1518111) in strong linkage disequilibrium with rs1800896

    Framework for evaluating the health impact of the scale-up of malaria control interventions on all-cause child mortality in Sub-Saharan Africa

    Get PDF
    Concerted efforts from national and international partners have scaled up malaria control interventions, including insecticide-treated nets, indoor residual spraying, diagnostics, prompt and effective treatment of malaria cases, and intermittent preventive treatment during pregnancy in sub-Saharan Africa (SSA). This scale-up warrants an assessment of its health impact to guide future efforts and investments; however, measuring malaria-specific mortality and the overall impact of malaria control interventions remains challenging. In 2007, Roll Back Malaria's Monitoring and Evaluation Reference Group proposed a theoretical framework for evaluating the impact of full-coverage malaria control interventions on morbidity and mortality in high-burden SSA countries. Recently, several evaluations have contributed new ideas and lessons to strengthen this plausibility design. This paper harnesses that new evaluation experience to expand the framework, with additional features, such as stratification, to examine subgroups most likely to experience improvement if control programs are working; the use of a national platform framework; and analysis of complete birth histories from national household surveys. The refined framework has shown that, despite persisting data challenges, combining multiple sources of data, considering potential contributions from both fundamental and proximate contextual factors, and conducting subnational analyses allows identification of the plausible contributions of malaria control interventions on malaria morbidity and mortality

    Proton and photon radiotherapy in stage III NSCLC:Effects on hematological toxicity and adjuvant immune therapy

    Get PDF
    Background and purpose: Concurrent chemo-radiotherapy (CCRT) followed by adjuvant durvalumab is standard-of-care for fit patients with unresectable stage III NSCLC. Intensity modulated proton therapy (IMPT) results in different doses to organs than intensity modulated photon therapy (IMRT). We investigated whether IMPT compared to IMRT reduce hematological toxicity and whether it affects durvalumab treatment. Materials and methods: Prospectively collected series of consecutive patients with stage III NSCLC receiving CCRT between 06.16 and 12.22 (staged with FDG-PET-CT and brain imaging) were retrospectively analyzed. The primary endpoint was the incidence of lymphopenia grade ≥ 3 in IMPT vs IMRT treated patients. Results: 271 patients were enrolled (IMPT: n = 71, IMRT: n = 200) in four centers. All patients received platinum-based chemotherapy. Median age: 66 years, 58 % were male, 36 % had squamous NSCLC. The incidence of lymphopenia grade ≥ 3 during CCRT was 67 % and 47 % in the IMRT and IMPT group, respectively (OR 2.2, 95 % CI: 1.0–4.9, P = 0.03). The incidence of anemia grade ≥ 3 during CCRT was 26 % and 9 % in the IMRT and IMPT group respectively (OR = 4.9, 95 % CI: 1.9–12.6, P = 0.001). IMPT was associated with a lower rate of Performance Status (PS) ≥ 2 at day 21 and 42 after CCRT (13 % vs. 26 %, P = 0.04, and 24 % vs. 39 %, P = 0.02). Patients treated with IMPT had a higher probability of receiving adjuvant durvalumab (74 % vs. 52 %, OR 0.35, 95 % CI: 0.16–0.79, P = 0.01). Conclusion: IMPT was associated with a lower incidence of severe lymphopenia and anemia, better PS after CCRT and a higher probability of receiving adjuvant durvalumab.</p

    Shadowing in Inelastic Scattering of Muons on Carbon, Calcium and Lead at Low XBj

    Full text link
    Nuclear shadowing is observed in the per-nucleon cross-sections of positive muons on carbon, calcium and lead as compared to deuterium. The data were taken by Fermilab experiment E665 using inelastically scattered muons of mean incident momentum 470 GeV/c. Cross-section ratios are presented in the kinematic region 0.0001 < XBj <0.56 and 0.1 < Q**2 < 80 GeVc. The data are consistent with no significant nu or Q**2 dependence at fixed XBj. As XBj decreases, the size of the shadowing effect, as well as its A dependence, are found to approach the corresponding measurements in photoproduction.Comment: 22 pages, incl. 6 figures, to be published in Z. Phys.

    Deaths due to differentiated thyroid cancer: A 46-year perspective

    Full text link
    From 1940 to 1986, a total of 798 patients were treated for differentiated thyroid carcinoma. One hundred and seventy-two patients died during the follow-up period: 42 (24.4%) patients from thyroid cancer, 14 (8.1%) from other causes with extensive thyroid cancer present, 75 (43.6%) with no thyroid cancer, and 41 (23.8%) with an unknown status of thyroid cancer . Of the 42 patients dying due to thyroid cancer, 15 were male and 27, female. Mean age at diagnosis was 48.3±17.7 years with one-third of patients age 45 or younger at the time of the initial diagnosis. The primary tumors were large (>4 cm) and 59.5% of the patients had local invasion and/or cervical metastasis. Distant metastases were present in 9 (21.4%) patients at the time of diagnosis . Surgical therapy included total thyroidectomy (72.1%) and limited or radical neck dissection (69.4%). Radioactive iodine ( 131 I) was used to treat residual cancer and/or distant metastasis in 73.8% of the patients. External radiation therapy was used to treat locally advanced or recurrent disease in 52.3% of the patients. Distant metastases and local recurrence were identified earlier in patients with follicular thyroid cancer whose survival time and disease-free interval were significantly shorter ( p < 0.001) than that of patients with papillary neoplasms. However, the survival and disease-free intervals were often very long in both papillary and follicular thyroid cancer deaths . Onset of differentiated thyroid cancer before the age of 40 years does not preclude serious sequelae and death. Since no known histopathologic features can consistently predict outcome, we continue to advocate aggressive treatment of all patients with differentiated thyroid cancer . Entre 1940 et 1986, 798 patients au total ont été traités pour un cancer différencié de la thyroïde. Cent-soixant-douze patients sont morts par la suite: 42 (24.4%) de leur cancer, 14 (8.1%) d'une autre cause alors que des signes d'extension du cancer étaient présents, 75 (43.6%) d'une autre cause sans signe de cancer, et 41 (23.8%) sans qu'on ait pu connaître le stade du cancer. Des 42 patients morts de leur cancer, il y avait 15 hommes et 27 femmes. L'âge moyen au moment du diagnostic était de 48.3±17.7 ans: un tiers des patients avait 45 ans ou moins au moment du diagnostic. Les tumeurs primitives avaient plus de 4 cm et 59.5% des patients présentaient un envahissement local et/ou une métastase cervicale. Les métastases à distance ont été détectées chez 9 (21.4%) patients au moment du diagnostic. Une thyroïdectomie totale a été effectuée chez 72.1% des patients, associée à un curage cervical limité ou radical chez 69.4% des patients. Chez 73.8% des patients on a traité le tissu cancéreux résiduel et/ou des métastases à distance par de l'I 131. La radiothérapie a été utilisée pour traiter les patients présentant une extension importante ou une récidive chez 52.3% des patients. Des métastases à distance et des récidives ont été identifiées précocement chez les patients ayant un cancer folliculaire. Dans ce groupe de patients, la survie et l'intervalle de temps sans maladie étaient significativement plus courts ( p <0.001) que chez les patients ayant un cancer papillaire. Il faut cependant noter que la survie et l'intervalle de temps sans maladie étaient très longs dans les 2 groupes de patients. La découverte d'un cancer différencié de la thyroïde avant l'âge de 40 ans n'est pas un facteur pronostique particulier. Puisqu'il n'y pas de facteur histologique permettant de prévoir l'évolution, nous continuons de préconiser un traitement agressif chez tout patient présentant un cancer différencié de la thyroïde. En el período 1940–1986, un total de 798 pacientes recibieron tratamiento para carcinoma tiroideo; 172 murieron en el curso del seguimiento: 42 (24.4%) por cancer tiroideo, 14 (8.1%) por otras causas pero con presencia de extenso cáncer tiroideo, 75 (43.6%) libres de cáncer tiroideo, y 41 (23.8%) con estado desconocido en cuanto al cancer tiroideo.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/41283/1/268_2005_Article_BF01655866.pd
    corecore