804 research outputs found

    A multiwavelength study of young massive star forming regions: II. The dust environment

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    We present observations of 1.2-mm dust continuum emission, made with the Swedish ESO Submillimeter Telescope, towards eighteen luminous IRAS point sources, all with colors typical of compact HII regions and associated with CS(2-1) emission, thought to be representative of young massive star forming regions. Emission was detected toward all the IRAS objects. We find that the 1.2-mm sources associated with them have distinct physical parameters, namely sizes of 0.4 pc, dust temperatures of 30 K, masses of 2x10^3 Msun, column densities of 3x10^23 cm^-2, and densities of 4x10^5 cm^-3. We refer to these dust structures as massive and dense cores. Most of the 1.2-mm sources show single-peaked structures, several of which exhibit a bright compact peak surrounded by a weaker extended envelope. The observed radial intensity profiles of sources with this type of morphology are well fitted with power-law intensity profiles with power-law indices in the range 1.0-1.7. This result indicates that massive and dense cores are centrally condensed, having radial density profiles with power-law indices in the range 1.5-2.2. We also find that the UC HII regions detected with ATCA towards the IRAS sources investigated here (Paper I) are usually projected at the peak position of the 1.2-mm dust continuum emission, suggesting that massive stars are formed at the center of the centrally condensed massive and dense cores.Comment: 6 figures, accepted by Ap

    Cloud Manufacturing: state of the art and evaluation of the BaSyx project

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    The emergence of new technologies such as the Internet of Things (IoT) and Cloud Computing hasstrongly boosted the manufacturing industry, opening the doors to a much broader world ofpossibilities and starting what many consider to be the Fourth Industrial Revolution. In this context iswhere the manufacturing paradigm of Cloud Manufacturing (CMfg) emerges, with the goal to connectmanufacturing processes through the Cloud in such a way that it allows different organizations tocooperate and to offer services to customers that could not be possible by their own independently. Asystematic review of the literature was carried out in order to determine the main characteristics andfunctionalities that a CMfg system should provide as well as the main current lines of research in thisregard. Then, we developed a prototype CMfg system based on the open source middleware EclipseBaSyx, a software development kit for CMfg systems. The developed prototype consists of a webinterface module that allows different users to create new machines and to insert job orders from thecustomers, and a server logic module that is responsible for accepting jobs, dividing them intosubtasks and distributing them among the different machines that work independently from eachother. The web module is composed by three main sub-modules: 1) a scheduler to control anddistribute the orders among the different machines of the system; 2) a verifier, which is in charge ofmonitoring the state of the machines in the real time, collecting a large amount of information fromthem and notifying the scheduler in case of failures or when they need special attention; and 3) aBaSyx module that is in charge of the creation of the Digital Twins. Finally, several numericalexperiments were carried out to show the potential of BaSyx for leveraging different productionplanning and operations management problems that may arise under Cloud Manufacturingenvironments.Fil: Videla Helal, Matías Emiliano. Universidad de la República; UruguayFil: Chiappa Curbelo, Carlos S.. Universidad de la República; UruguayFil: Piñeyro, Pedro. Universidad de la República; UruguayFil: Viana, Víctor. Universidad de la República; UruguayFil: Rossit, Daniel Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Matemática Bahía Blanca. Universidad Nacional del Sur. Departamento de Matemática. Instituto de Matemática Bahía Blanca; Argentina. Universidad Nacional del Sur. Departamento de Ingeniería; ArgentinaXXI Latin Ibero-American Conference on Operations Research -CLAIO 2022Buenos AiresArgentinaUniversidad de Buenos Aires. Facultad de Ciencias Exactas y Naturale

    Circumcision and penile human papillomavirus prevalence in human immunodeficiency virus-infected men: heterosexual and men who have sex with men

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    AbstractMale circumcision is associated with a lower risk of penile human papillomavirus (HPV) infection in human immunodeficiency virus (HIV) uninfected men. Few studies have evaluated the role of male circumcision in penile HPV infection in HIV-infected men. The aim of this cross-sectional study was to examine the association between male circumcision and the prevalence of penile HPV infection among HIV-infected men—both men who have sex with men (MSM) and heterosexual men. Samples from 706 consecutive men included in the CARH-MEN cohort (overall 24% circumcised: 26% of MSM, 18% of heterosexual men) were examined by Multiplex-PCR. In the overall group (all HIV-infected men included), the prevalence of any penile HPV infection was 22% in circumcised men and 27% in uncircumcised men (OR = 1.0, 95% CI 0.6–1.6, adjusted analysis). In the circumcised group the overall prevalence of HPV infection was 22% in MSM and 24% in the heterosexual men, whereas in the uncircumcised group the prevalence was 26% and 28%, respectively. The prevalence of high-risk HPV types tended to be lower in the circumcised MSM (14% vs 21%, OR = 0.6, 95% CI 0.3–1.1, p 0.088), but it was similar in the heterosexual men (18% in circumcised vs 20% in uncircumcised). These results suggest that male circumcision may be associated with a lower prevalence of oncogenic high-risk penile HPV infection in HIV-infected MSM

    Aqueous electrolytes confined within functionalized silica nanopores

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    Molecular dynamics simulations have been carried out to investigate structural and dynamical characteristics of NaCl aqueous solutions confined within silica nanopores in contact with a “bulk-like” reservoir. Two types of pores, with diameters intermediate between 20 Å and 37.5 Å, were investigated: The first one corresponded to hydrophobic cavities, in which the prevailing wall-solution interactions were of the Lennard-Jones type. In addition, we also examined the behavior of solutions trapped within hydrophilic cavities, in which a set of unsaturated O-sites at the wall were transformed in polar silanol Si–OH groups. In all cases, the overall concentrations of the trapped electrolytes exhibited important reductions that, in the case of the narrowest pores, attained 50% of the bulk value. Local concentrations within the pores also showed important fluctuations. In hydrophobic cavities, the close vicinity of the pore wall was coated exclusively by the solvent, whereas in hydrophilic pores, selective adsorption of Na+ ions was also observed. Mass and charge transport were also investigated. Individual diffusion coefficients did not present large codifications from what is perceived in the bulk; contrasting, the electrical conductivity exhibited important reductions. The qualitative differences are rationalized in terms of simple geometrical considerations.Peer ReviewedPostprint (published version

    Pharmacokinetics of intravenous and subcutaneous cefovecin in alpacas

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    The purpose of this study was to determine the pharmacokinetics of cefovecin after intravenous and subcutaneous dose of 8 mg/kg to alpacas. Bacterial infections requiring long‐term antibiotic therapy such as neonatal bacteremia, pneumonia, peritonitis, dental, and uterine infections are a significant cause of morbidity and mortality in this species. However, few antimicrobials have been evaluated and proven to have favorable pharmacokinetics for therapeutic use. Most antimicrobials that are currently used require daily injections for many days. Cefovecin is a long‐acting cephalosporin that is formulated for subcutaneous administration, and its long‐elimination half‐life allows for 14‐day dosing intervals in dogs and cats. The properties of cefovecin may be advantageous for medical treatment of camelids due to its broad spectrum, route of administration, and long duration of activity. Pharmacokinetic evaluation of antimicrobial drugs in camelids is essential for the proper treatment and prevention of bacterial disease, and to minimize development of antibiotic resistant bacterial strains due to inadequate antibiotic concentrations. Cefovecin mean half‐life, volume of distribution at steady‐state, and clearance after intravenous administration were 10.3 h, 86 mL/kg, and 7.07 mL·h/kg. The bioavailability was 143%, while half‐life, Cmax, and Tmax were 16.9 h, 108 μg/mL, and 2.8 h following subcutaneous administration. In the absence of additional microbial susceptibility data for alpaca pathogens, the current cefovecin dosage regimen prescribed for dogs (8 mg/kg SC every 14 days) may need to be optimized for the treatment of infections in this species

    Delayed gastric emptying after classical Whipple or pylorus-preserving pancreatoduodenectomy: a randomized clinical trial (QUANUPAD)

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    Purpose Pylorus-preserving pancreatoduodenectomy (PPPD) has been the gold standard for pancreatic head lesion resection for several years. Some studies have noted that it involves more delayed gastric emptying (DGE) than classical Whipple (i.e., pancreatoduodenectomy with antrectomy). Our working hypothesis was that the classical Whipple has a lower incidence of DGE. We aimed to compare the incidence of DGE among pancreatoduodenectomy techniques. Methods This pragmatic, randomized, open-label, single-center clinical trial involved patients who underwent classical Whipple (study group) or PPPD (control group). Gastric emptying was clinically evaluated using scintigraphy. DGE was defined according to the International Study Group of Pancreatic Surgery (ISGPS) criteria. The secondary endpoints were postoperative morbidity, length of hospital stay, anthropometric measurements, and nutritional status. Results A total of 84 patients were randomized (42 per group). DGE incidence was 50% (20/40, 95% confidence interval (95% CI): 35-65%) in the study group and 62% (24/39, 95% CI: 46-75%) in the control group (p = 0.260). No differences were observed between both groups regarding postoperative morbidity or length of hospital stay. Anthropometric measurements at 6 months post-surgery: triceps fold measurements were 12 mm and 16 mm (p = 0.021). At 5 weeks post-surgery, triceps fold measurements were 13 mm and 16 mm (p = 0.020) and upper arm circumferences were 26 cm and 28 cm (p = 0.030). No significant differences were observed in nutritional status. Conclusion DGE incidence and severity did not differ between classical Whipple and PPPD. Some anthropometric measurements may indicate a better recovery with PPPD

    Experiencia en el uso del aula virtual para el proceso de enseñanza y aprendizaje de sustitución por radicales libres

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    Es indiscutible que estamos asistiendo a un cambio sustancial en la manera en que el estudiante construye el saber y los docentes debemos ser partícipes de esa construcción. El aprendizaje centrado en la actividad del alumno y el empleo de las nuevas tecnologías de información y comunicación son los dos ejes del mejoramiento de la calidad de la enseñanza universitaria actual. Se presenta una experiencia de uso de TIC cuyo objetivo es lograr que los estudiantes mejoren su rendimiento académico mediante una propuesta que promueve el aprendizaje significativo del contenido Sustitución por Radicales Libres, en la asignatura Química Orgánica de la Facultad de Ingeniería de la UNCuyo. El trabajo muestra la implementación y la valoración del uso de la secuencia didáctica, además de las dificultades encontradas. Los resultados obtenidos nos animan a seguir innovando con nuevas propuestas TIC y, en particular, en el mencionado contenido.Eje 4 - Mesa 4.Dirección de Educación a Distancia, Innovación en el aula y TIC (EAD
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