717 research outputs found

    K-->pipi amplitudes from lattice QCD with a light charm quark

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    We compute the leading-order low-energy constants of the DeltaS=1 effective weak Hamiltonian in the quenched approximation of QCD with up, down, strange, and charm quarks degenerate and light. They are extracted by comparing the predictions of finite volume chiral perturbation theory with lattice QCD computations of suitable correlation functions carried out with quark masses ranging from a few MeV up to half of the physical strange mass. We observe a large DeltaI=1/2 enhancement in this corner of the parameter space of the theory. Although matching with the experimental result is not observed for the DeltaI=1/2 amplitude, our computation suggests large QCD contributions to the physical DeltaI=1/2 rule in the GIM limit, and represents the first step to quantify the role of the charm quark-mass in K-->pipi amplitudes.Comment: 4 pages, 1 figure. Minor modifications. Final version to appear on PR

    Non-perturbative renormalisation of left-left four-fermion operators with Neuberger fermions

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    We outline a general strategy for the non-perturbative renormalisation of composite operators in discretisations based on Neuberger fermions, via a matching to results obtained with Wilson-type fermions. As an application, we consider the renormalisation of the four-quark operators entering the Delta S=1 and Delta S=2 effective Hamiltonians. Our results are an essential ingredient for the determination of the low-energy constants governing non-leptonic kaon decays.Comment: 14 pages, 3 figure

    On the optimal indoor air conditions for sars-cov-2 inactivation. An enthalpy-based approach

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    In the CoViD-19 pandemic, the precautionary approach suggests that all possible measures should be established and implemented to avoid contagion, including through aerosols. For indoor spaces, the virulence of SARS-CoV-2 could be mitigated not only via air changes, but also by heating, ventilation, and air conditioning (HVAC) systems maintaining thermodynamic conditions possibly adverse to the virus. However, data available in literature on virus survival were never treated aiming to this. In fact, based on comparisons in terms of specific enthalpy, a domain of indoor comfort conditions between 50 and 60 kJ/kg is found to comply with this objective, and an easy-to-use relationship for setting viable pairs of humidity and temperature using a proper HVAC plant is proposed. If confirmed via further investigations on this research path, these findings could open interesting scenarios on the use of indoor spaces during the pandemic

    Predicting sars-cov-2 weather-induced seasonal virulence from atmospheric air enthalpy

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    Following the coronavirus disease 2019 (COVID-19) pandemic, several studies have examined the possibility of correlating the virulence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, to the climatic conditions of the involved sites; however, inconclusive results have been generally obtained. Although neither air temperature nor humidity can be independently correlated with virus viability, a strong relationship between SARS-CoV-2 virulence and the specific enthalpy of moist air appears to exist, as confirmed by extensive data analysis. Given this framework, the present study involves a detailed investigation based on the first 20-30 days of the epidemic before public health interventions in 30 selected Italian provinces with rather different climates, here assumed as being representative of what happened in the country from North to South, of the relationship between COVID-19 distributions and the climatic conditions recorded at each site before the pandemic outbreak. Accordingly, a correlating equation between the incidence rate at the early stage of the epidemic and the foregoing average specific enthalpy of atmospheric air was developed, and an enthalpy-based seasonal virulence risk scale was proposed to predict the potential danger of COVID-19 outbreak due to the persistence of weather conditions favorable to SARS-CoV-2 viability. As an early detection tool, an unambiguous risk chart expressed in terms of coupled temperatures and relative humidity (RH) values was provided, showing that safer conditions occur in the case of higher RHs at the highest temperatures, and of lower RHs at the lowest temperatures. Despite the complex determinism and dynamics of the pandemic and the related caveats, the restriction of the study to its early stage allowed the proposed risk scale to result in agreement with the available infectivity data highlighted in the literature for a number of cities around the world

    The impact of integrating food supplementation, nutritional education and HAART (Highly Active Antiretroviral Therapy) on the nutritional status of patients living with HIV/AIDS in Mozambique: result from the DREAM programme

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    DREAM (Drug Resources Enhancement against AIDS and Malnutrition) is a multiregional health program active in Mozambique since 2002 and provides free of charge an integrating package of care consisting of peer to peer nutritional and health education, food supplementation, voluntary counseling and testing, immunological, virological, clinical assessment and HAART (Highly Active AntiRetroviral Treatment). The main goals of this paper are to describe the state of health and nutrition and the adequacy of the diet of a sample of HIV/AIDS patients in Mozambique on HAART and not. A single-arm retrospective cohort study was conducted. 106 HIV/AIDS adult patients (84 in HAART), all receiving food supplementation and peer-to-peer nutritional education, were randomly recruited in Mozambique in two public health centres where DREAM is running. The programme is characterized by: provision of HAART, clinical and laboratory monitoring, peer to peer health and nutritional education and food supplementation. We measured BMI, haemoglobin, viral load, CD4 count at baseline (T0) and after at least 1 year (T1). Dietary intake was estimated using 24h food recall and dietary diversity was assessed by using the Dietary Diversity Score (DDS) at T1. Overall, the patients'diet appeared to be quite balanced in nutrients. In the cohort not in HAART the mean BMI values showed an increases but not significant (initial value: 21.9±2.9; final value: 22.5±3.3 ) and the mean haemoglobin values (g/dl) showed a significant increases (initial value: 10.5+ 2.1; final value: 11.5±1.7 p< 0.024) . In the cohort in HAART, both the mean of BMI value (initial value: 20.7±3.9; final value: 21.9±3.3 p< 0.001) and of haemoglobin (initial value: 9.9±2.2; final value: 10.8±1.7 p< 0.001) showed a higher significant increase. The increase in BMI was statistically associated with the DDS in HAART patients. In conclusion nutritional status improvement was observed in both cohorts. The improvement in BMI was significant and substantially higher in HAART patients because of the impact of HAART on nutritional status of AIDS patients. Subjects on HAART and with a DDS > 5, showed a substantial BMI gain. This association showed an additional expression of the synergic effect of integrating food supplementation, nutritional education and HAART on the nutritional status of African AIDS patients and also highlights the complementary role of an adequate and diversified diet in persons living with HIV/AIDS in resources limited settings

    COVID-19 and Iraqi Kurdistan: A regional case in the middle east

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    The unfolding Covid-19 is posing worldwide health and socio-economic threats. As most of the world attention is concentrated upon a few countries, in many fragile areas, the impact of the pandemic on the health systems might be even higher, but risks staying hidden from public consideration. This is the case of Iraq where Covid-19 is a further burden on an already weakened public health system. This study draws attention to the Autonomous Region of the Iraqi Kurdistan, that before the emergency was investing in the rebuilding of its public health system after decades of tensions and conflicts. Information on governmental measures for COVID-19 containment and response, management approaches, prevention interventions, and public opinion reactions have been collected from official sources, websites and from interviews with the local staff working in the field. The experience of the Iraqi Kurdistan opens new opportunities for reflection on how a war-torn region is dealing with the COVID-19 outbreak. Acquiring knowledge on the health needs of such a fragile area holds a paramount importance for providing preparedness planning and enhancing resilience of the public health system in case of future disasters. The lesson learnt might be useful for other regions living in similar contexts

    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

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    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

    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

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    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 (&gt;15 beds) versus smaller (&lt;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

    Pro-active monitoring and social interventions at community level mitigate the impact of coronavirus (COVID-19) epidemic on older adults' mortality in Italy: A retrospective cohort analysis

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    Background The COVID-19 epidemic in Italy has severely affected people aged more than 80, especially socially isolated. Aim of this paper is to assess whether a social and health program reduced mortality associated to the epidemic. Methods An observational retrospective cohort analysis of deaths recorded among &gt;80 years in three Italian cities has been carried out to compare death rate of the general population and "Long Live the Elderly!"(LLE) program. Parametric and non-parametric tests have been performed to assess differences of means between the two populations. A multivariable analysis to assess the impact of covariates on weekly mortality has been carried out by setting up a linear mixed model. Results The total number of services delivered to the LLE population (including phone calls and home visits) was 34,528, 1 every 20 day per person on average, one every 15 days during March and April. From January to April 2019, the same population received one service every 41 days on average, without differences between January-February and March-April. The January-April 2020 cumulative crude death rate was 34.8 (9,718 deaths out of 279,249 individuals; CI95%: 34.1-35.5) and 28.9 (166 deaths out of 5,727 individuals; CI95%:24.7-33.7) for the general population and the LLE sample respectively. The general population weekly death rate increased after the 11th calendar week that was not the case among the LLE program participants (p&lt;0.001). The Standardized Mortality Ratio was 0.83; (CI95%: 0.71-0.97). Mortality adjusted for age, gender, COVID-19 weekly incidence and prevalence of people living in nursing homes was lower in the LLE program than in the general population (p&lt;0.001). Conclusions LLE program is likely to limit mortality associated with COVID-19. Further studies are needed to establish whether it is due to the impact of social care that allows a better clients' adherence to the recommendations of physical distancing or to an improved surveillance of older adults that prevents negative outcomes associated with COVID-19

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

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    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 998andcostperDALYsavedwasUS998 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,largelyunderthethresholdgivenbythepercapitayearlyincomeinMalawi(US50, 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
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