455 research outputs found

    Computational analysis of transport in three-dimensional heterogeneous materials: An OpenFOAMÂź-based simulation framework

    Get PDF
    Porous and heterogeneous materials are found in many applications from composites, membranes, chemical reactors, and other engineered materials to biological matter and natural subsurface structures. In this work we propose an integrated approach to generate, study and upscale transport equations in random and periodic porous structures. The geometry generation is based on random algorithms or ballistic deposition. In particular, a new algorithm is proposed to generate random packings of ellipsoids with random orientation and tunable porosity and connectivity. The porous structure is then meshed using locally refined Cartesian-based or unstructured strategies. Transport equations are thus solved in a finite-volume formulation with quasi-periodic boundary conditions to simplify the upscaling problem by solving simple closure problems consistent with the classical theory of homogenisation for linear advection–diffusion–reaction operators. Existing simulation codes are extended with novel developments and integrated to produce a fully open-source simulation pipeline. A showcase of a few interesting three-dimensional applications of these computational approaches is then presented. Firstly, convergence properties and the transport and dispersion properties of a periodic arrangement of spheres are studied. Then, heat transfer problems are considered in a pipe with layers of deposited particles of different heights, and in heterogeneous anisotropic materials

    Pneumococcal vaccination in adults: rationale, state of the art and perspectives

    Get PDF
    Streptococcus pneumoniae (SP) is a leading cause of morbid- ity and mortality worldwide. Despite the availability, since the early 1980s, of a 23-valent pneumococcal polysaccharide vaccine (PPV23), its recommendation and increased use in the last decades, and the indirect benefits against invasive pneumococcal diseases following the pediatric immunization strategies with the 7-valent pneumococcal conjugate vaccine (PCV7), pneumoccal diseases, particularly Community Acquired Pneumonia (CAP), still remain a substantial burden among older adults in Western countries. The recent availability on the market of a second generation of pneumococcal conjugate vaccines, with an enlarged spectrum ofprotection against some serotypes not included in the PCV7 (i.e., the 13-valent pneumococcal conjugate vaccine ? PCV13), opens new interesting perspectives for improving the control of this sig- nificant health-care issue among the entire population. The most interesting and up-dated epidemiological data regard- ing the impact of SP in adults and the elderly in Western countries, together with the available evidence concerning the efficacy and effectiveness of the PPV23 in the same population, are reported and discussed below. The full article is free available on www.jpmh.or

    COVID-19 and Seasonal Influenza Vaccination: Cross-Protection, Co-Administration, Combination Vaccines, and Hesitancy

    Get PDF
    SARS-CoV-2 and influenza are the main respiratory viruses for which effective vaccines are currently available. Strategies in which COVID-19 and influenza vaccines are administered simultaneously or combined into a single preparation are advantageous and may increase vaccination uptake. Here, we comprehensively review the available evidence on COVID-19/influenza vaccine coadministration and combination vaccine candidates from the standpoints of safety, immunogenicity, efficacy, policy and public acceptance. While several observational studies have shown that the trained immunity induced by influenza vaccines can protect against some COVID-19-related endpoints, it is not yet understood whether co-administration or combination vaccines can exert additive effects on relevant outcomes. In randomized controlled trials, co-administration has proved safe, with a reactogenicity profile similar to that of either vaccine administered alone. From the immunogenicity standpoint, the immune response towards four influenza strains and the SARS-CoV-2 spike protein in co-administration groups is generally non-inferior to that seen in groups receiving either vaccine alone. Several public health authorities have advocated co-administration. Different combination vaccine candidates are in (pre)-clinical development. The hesitancy towards vaccine co-administration or combination vaccines is a multifaceted phenomenon and may be higher than the acceptance of either vaccine administered separately. Public health implications are discussed

    Cost-Effectiveness of Vaccination with the 20-Valent Pneumococcal Conjugate Vaccine in the Italian Adult Population

    Get PDF
    The availability of a new 20-valent pneumococcal conjugate vaccine (PCV) makes it appropriate to assess its cost-effectiveness. This was evaluated by adopting the Italian National Health Service perspective, using a cost consequences Markovian model. The expected effects of vaccination with 20-valent PCV were compared with the administration of 13-valent PCV and 15-valent PCV. Assuming a 100% vaccination of cohorts aged 65–74 years, in the (lifetime) comparison between 20-valent PCV and 13-valent PCV, the former is dominant (lower cost for a better health outcome). A reduction in disease events was estimated: −1208 deaths; −1171 cases of bacteraemia; −227 of meningitis; −9845 hospitalised all-cause nonbacteremic pneumonia cases (NBP) and −21,058 non-hospitalised. Overall, in the Italian population, a total gain of 6581.6 life years and of 4734.0 QALY was estimated. On the cost side, against an increase in vaccinations costs (EUR +40.568 million), other direct health costs are reduced by EUR 48.032 million, with a net saving of EUR +7.464 million. The comparison between 20-valent PCV and 15-valent PCV results in an Incremental Cost-Effectiveness Ratio (ICER) of EUR 66 per life year gained and EUR 91 per QALY gained. The sensitivity analyses confirm the robustness of the results. We can conclude that the switch to 20-valent PCV is a sustainable and efficient investment

    Solving the Klein-Gordon equation using Fourier spectral methods: A benchmark test for computer performance

    Get PDF
    The cubic Klein-Gordon equation is a simple but non-trivial partial differential equation whose numerical solution has the main building blocks required for the solution of many other partial differential equations. In this study, the library 2DECOMP&FFT is used in a Fourier spectral scheme to solve the Klein-Gordon equation and strong scaling of the code is examined on thirteen different machines for a problem size of 512^3. The results are useful in assessing likely performance of other parallel fast Fourier transform based programs for solving partial differential equations. The problem is chosen to be large enough to solve on a workstation, yet also of interest to solve quickly on a supercomputer, in particular for parametric studies. Unlike other high performance computing benchmarks, for this problem size, the time to solution will not be improved by simply building a bigger supercomputer.Comment: 10 page

    Efficacy and safety of darunavir and etravirine in an antiretroviral multi-experienced youth with vertically HIV-1 infection

    Get PDF
    Multiclass-drug resistance, often caused by poor treatment compliance, is a challenging problem in all categories of HIV-infected patients. Selective pressure is higher in youth for both biological and behavioral reasons. We report the case of a 15-year-old Caucasian male, with vertically acquired HIV-1 infection, who failed several lines of antiretroviral therapy and was successfully treated with darunavir/ritonavir and etravirine

    Development and preliminary data on the use of a mobile app specifically designed to increase community awareness of invasive pneumococcal disease and its prevention

    Get PDF
    PublishedGiven the growing use and great potential of mobile apps, this project aimed to develop and implement a user-friendly app to increase laypeople's knowledge and awareness of invasive pneumococcal disease (IPD). Despite the heavy burden of IPD, the documented low awareness of IPD among both laypeople and healthcare professionals and far from optimal pneumococcal vaccination coverage, no app specifically targeting IPD has been developed so far. The app was designed to be maximally functional and conceived in accordance with user-centered design. Its content, layout and usability were discussed and formally tested during several workshops that involved the principal stakeholders, including experts in IPD and information technology and potential end-users. Following several workshops, it was decided that, in order to make the app more interactive, its core should be a personal “checker” of the risk of contracting IPD and a user-friendly risk-communication strategy. The checker was populated with risk factors identified through both Italian and international official guidelines. Formal evaluation of the app revealed its good readability and usability properties. A sister web site with the same content was created to achieve higher population exposure. Seven months after being launched in a price- and registration-free modality, the app, named “Pneumo Rischio,” averaged 20.9 new users/day and 1.3 sessions/user. The first in-field results suggest that “Pneumo Rischio” is a promising tool for increasing the population's awareness of IPD and its prevention through a user-friendly risk checker.The development of the app is a part of the project on increasing the population's awareness of invasive pneumococcal disease and has been supported by sponsorship from Pfizer S.r.l. The sponsor had no role in the app design and development. The authors thank Progetti di Impresa Srl for creating the app and website

    Outbreak of sars-cov-2 lineage 20i/501y.V1 in a nursing home underlines the crucial role of vaccination in both residents and staff

    Get PDF
    Elderly residents in nursing homes are at very high risk of life-threatening COVID-19-related outcomes. In this report, an epidemiological and serological investigation of a SARS-CoV-2 outbreak in an Italian nursing home is described. Among the residents, all but one (19/20) were regularly vaccinated against SARS-CoV-2. In mid-February 2021, a non-vaccinated staff member of the nursing home was diagnosed with the SARS-CoV-2 infection. Following the outbreak investigation, a total of 70% (14/20) of residents aged 77–100 years were found positive. The phylogenetic analysis showed that the outbreak was caused by the SARS-CoV-2 variant of concern 202012/01 (the so-called “UK variant”). However, all but one positive subjects (13/14) were fully asymptomatic. The only symptomatic patient was a vaccinated 86-year-old female with a highly compromised health background and deceased approximately two weeks later. The subsequent serological investigation showed that the deceased patient was the only vaccinated subject that did not develop the anti-spike protein antibody response, therefore being likely a vaccine non-responder. Although the available mRNA SARS-CoV-2 vaccine was not able to prevent several asymptomatic infections, it was able to avert most symptomatic disease cases caused by the SARS-CoV-2 variant of concern 202012/01 in nursing home residents

    Effects of Holder pasteurization on the protein profile of human milk

    Get PDF
    BACKGROUND: The most widespread method for the treatment of donor milk is the Holder pasteurization (HoP). The available literature data show that HoP may cause degradation of some bioactive components. The aim of this study was to determine the effect of HoP on the protein profile of human milk (HM) using a GeLC-MS method, a proteomic approach and a promising technique able to offer a qualitative HM protein profile. METHODS: HM samples were collected by standardized methods from 20 mothers carrying both preterm and term newborns. A aliquot of each sample was immediately frozen at -80 °C, whilst another one was Holder pasteurized and then frozen. All samples were then analyzed by GeLC-MS. The protein bands of interest were excised from the gel, digested with trypsin and identified by nano-HPLC-MS/MS analysis. RESULTS: The protein profile before and after HoP showed qualitative differences only in 6 samples out of 20, while in the remaining 14 no detectable differences were found. The differences interested only colostrums and transitional milk samples and regarded the decrease of the electrophoretic bands corresponding to alpha and beta-casein, tenascin, lactoferrin and immunoglobulin. CONCLUSIONS: In the majority of samples, HoP did not cause any modification, thereby preserving the biological activity of HM proteins
    • 

    corecore