Non-perturbative scale evolution of four-fermion operators in two-flavour QCD

We apply finite-size recursion techniques based on the Schrodinger functional formalism to determine the renormalization group running of four-fermion operators which appear in the Delta S=2 effective weak Hamiltonian of the Standard Model. Our calculations are done using O(a) improved Wilson fermions with N_f=2 dynamical flavours. Preliminary results are presented for the four-fermion operator which determines the B_K parameter in tmQCD.Comment: 7 pages, 2 figures, talk presented at Lattice2006 (Renormalization

APENet: LQCD clusters a la APE

Developed by the APE group, APENet is a new high speed, low latency, 3-dimensional interconnect architecture optimized for PC clusters running LQCD-like numerical applications. The hardware implementation is based on a single PCI-X 133MHz network interface card hosting six indipendent bi-directional channels with a peak bandwidth of 676 MB/s each direction. We discuss preliminary benchmark results showing exciting performances similar or better than those found in high-end commercial network systems.Comment: Lattice2004(machines), 3 pages, 4 figure

FastLMFI: An Efficient Approach for Local Maximal Patterns Propagation and Maximal Patterns Superset Checking

Maximal frequent patterns superset checking plays an important role in the efficient mining of complete Maximal Frequent Itemsets (MFI) and maximal search space pruning. In this paper we present a new indexing approach, FastLMFI for local maximal frequent patterns (itemset) propagation and maximal patterns superset checking. Experimental results on different sparse and dense datasets show that our work is better than the previous well known progressive focusing technique. We have also integrated our superset checking approach with an existing state of the art maximal itemsets algorithm Mafia, and compare our results with current best maximal itemsets algorithms afopt-max and FP (zhu)-max. Our results outperform afopt-max and FP (zhu)-max on dense (chess and mushroom) datasets on almost all support thresholds, which shows the effectiveness of our approach.Comment: 8 Pages, In the proceedings of 4th ACS/IEEE International Conference on Computer Systems and Applications 2006, March 8, 2006, Dubai/Sharjah, UAE, 2006, Page(s) 452-45

Characteristics of nursing homes and early preventive measures associated with risk of infection from COVID-19 in Lazio region, Italy: a retrospective case-control study

Objectives To understand which organisational-structural characteristics of nursing homes - also referred to as long-term care facilities (LTCFs) - and the preventative measures adopted in response to the pandemic are associated with the risk of a COVID-19 outbreak. Setting LTCFs in Lazio region in Italy. Design The study adopts a case-control design. Participants We included 141 facilities and 100 provided information for the study. Cases were defined as facilities reporting a COVID-19 outbreak (two or more cases) in March-December 2020; controls were defined as LTCFs reporting one case or zero. The exposures include the structural-organisational characteristics of the LTCFs as reported by the facilities, preventative measures employed and relevant external factors. Results Twenty facilities reported an outbreak of COVID-19. In binary logistic regression models, facilities with more than 15 beds were five times more likely to experience an outbreak than facilities with less than 15 beds OR=5.60 (CI 1.61 to 25.12; p value 0.002); admitting new residents to facilities was associated with a substantially higher risk of an outbreak: 6.46 (CI 1.58 to 27.58, p value 0.004). In a multivariable analysis, facility size was the only variable that was significantly associated with a COVID-19 outbreak OR= 5.37 (CI 1.58 to 22.8; p value 0.012) for larger facilities (>15 beds) versus smaller (<15 beds). Other characteristics and measures were not associated with an outbreak. Conclusion There was evidence of a higher risk of COVID-19 in larger facilities and when new patients were admitted during the pandemic. All other structural-organisational characteristics and preventative measures were not associated with an outbreak. This finding calls into question existing policies, especially where there is a risk of harm to residents. One such example is the restriction of visitor access to facilities, resulting in the social isolation of residents

Interference coloration as an anti-predator defence

Interference coloration, in which the perceived colour varies predictably with the angle of illumination or observation, is extremely widespread across animal groups. However, despite considerable advances in our understanding of the mechanistic basis of interference coloration in animals, we still have a poor understanding of its function. Here, I show, using avian predators hunting dynamic virtual prey, that the presence of interference coloration can significantly reduce a predator's attack success. Predators required more pecks to successfully catch interference-coloured prey compared with otherwise identical prey items that lacked interference coloration, and attacks against prey with interference colours were less accurate, suggesting that changes in colour or brightness caused by prey movement hindered a predator's ability to pinpoint their exact location. The pronounced antipredator benefits of interference coloration may explain why it has evolved independently so many times. © 2015 The Author(s) Published by the Royal Society. All rights reserved

Improving Male Partner Involvement in HIV-Positive Women's Care Through Behavioral Change Interventions in Malawi (WeMen Study): A Prospective, Controlled Before-and-After Study

Several strategies and interventions have been implemented to improve male partner involvement (MI) in Sub-Saharan Africa, but evidence on successful interventions is scarce. This controlled before-and-after intervention study aims to evaluate the impact of three interventions on male partners' involvement in HIV+ women's care in Malawi. We piloted these three interventions: the organization of a special day for men, the deployment of male champions in communities to increase awareness on MI, and the delivery of an incentive (food package) for couples attending the facility. We observed a significant increase in the number of women accompanied by their partners (from 48.5 to 81.4%) and the number of women feeling safe at home (from 63.5 to 95.2%) after the special day intervention. This outcome increased after the deployment of male champions in communities (from 44.0 to 75.0%). No significant improvement was observed in the site where we delivered the incentive to couples. Our findings showed that the special day for men and the use of male champions might effectively increase the male involvement in the health of their female partners

Cost-Effectiveness of Using HAART in Prevention of Mother-To-Child Transmission in the DREAM-Project Malawi

Introduction: Cost-effectiveness analysis are crucial in the management of the HIV/AIDS epidemic, particularly in resource-limited settings. Such analyses have not been performed in the use of highly active antiretroviral therapy (HAART) for prevention of mother-to-child transmission (PMTCT). Objective: Cost-effectiveness analysis of HAART approach in Malawi for PMTCT. Methods: In 2 health centres in Malawi 6500 pregnant women were tested; 1118 pregnant women completed the entire Drug Resource Enhancement against Aids and Malnutrition-Project Malawi (DREAM - PM) PMTCT protocol. The costs of the intervention were calculated using the ingredients method. Outcomes estimated were cost for infection averted and cost for DALY saved compared with no intervention. Results: From a private perspective cost for HIV infection averted was US $998 and cost per DALY saved was US$35.36. From a public perspective, the result became negative as follows: −261 and −16.55, respectively (lower cost than the cost of the therapy for an HIV+ child). The univariate sensitivity analysis showed that the cost for DALY saved always remained under the threshold of US $50, largely under the threshold given by the per capita yearly income in Malawi (US$667 PPD). Conclusions: Administration of HAART in a PMTCT programme in resource-limited settings is cost-effective. Drugs and laboratory tests are the most significant costs, but further reduction of these expenses is possible

Extended antenatal antiretroviral use correlates with improved infant outcomes throughout the first year of life

OBJECTIVES: To evaluate the effect of extended antenatal triple antiretroviral therapy (ART) on infant outcomes. DESIGN: Retrospective cohort study using pooled data from health clinics in Malawi and Mozambique from July 2005 to December 2009. METHODS: Computerized records of 3273 HIV-infected pregnant women accessing Drug Resource Enhancement Against AIDS and Malnutrition centers were reviewed. ART regimens consisted of nevirapine-based HAART as of 14-25 weeks gestation until 6 months postpartum. Infant infection was determined at 1, 6 and 12 months of age by branched DNA. RESULTS: A total of 3071 pregnancies resulted in 3148 live births. Lost to follow-up, infant deaths and HIV-1 infection rates at 1 and 12 months were 1.3 and 11.5, 0.8 and 6.7 and 0.8 and 2.0, respectively. Infant HIV-1-free survival at 12 months was 92.5%. Mother-to-child transmission and/or infant deaths correlated with length of maternal antenatal ART by multivariate analysis at 1, 6 and 12 months: 14% in women with more than 30 days of triple antenatal ART and 6.9% in mothers receiving at least 90 days of antenatal ART, P = 0.001. Fifty percent of 54 episodes of transmission occurred in women with higher CD4 cell counts (>350 cells/μl). Infant mortality was 67/1000, lower than background rates (78-100/1000). Growth failure (weight-for-age Z score <-2) was present in 8% of infants around birth, 6% at 6 months, 23% at 12 months (lower than country-specific rates). CONCLUSION: Extended antenatal ART is protective against adverse infant outcomes up to 12 months of age even in children born to mothers with higher CD4 cell counts. PMID: 2088528