Energy and exergy analysis of microchannel central solar receivers for pressurised fluids

Within the new generation of advanced central solar receivers, microchannel pressurised gas receivers are emerging as reliable and efficient alternatives to operate at high temperatures and pressures. This paper presents an optimisation and comparative analysis of different compact plate-fin type structures, constituting the receiver’s absorber panels, classified according to the type of fin arrangement inside: plain rectangular, plain triangular, wavy, offset strip, perforated, and louvred fin. A versatile thermo-fluid receiver model is implemented, allowing simple variation of characteristic geometric parameters of each structure. Exergy efficiency is chosen as the optimisation function, as it considers both heat and pressure losses. The framework of the analysis is set by the receiver’s boundary conditions, operating at the design point conditions of a solar thermal power plant. For each compact structure, the optimal configuration is determined, providing interesting findings that have not been reported in the state-of-the-art to date. Although all geometries show good thermal performance, the perforated and plain rectangular configurations demonstrate the best exergy efficiencies of 59.21% and 58.80%, respectively, favouring taller and narrower channels. This analysis methodology could be seamlessly extrapolated to other gases and working conditions, owing to the thermo-fluid model’s versatility, to reveal the optimal configuration for each case.This work has been developed within the framework of the ACES2030-CM project, funded by the Regional Research and Development in Technology Programme 2018 (ref. P2018/EMT-4319). The authors would like to thank the support of the Spanish Ministry of Economy and Competitiveness through the PID2019-110283RB-C31 project

Performance of a direct steam generation solar thermal power plant for electricity production as a function of the solar multiple

This paper describes the influence of the solar multiple on the annual performance of parabolic trough solar thermal power plants with direct steam generation (DSG). The reference system selected is a 50 M We DSG power plant, with thermal storage and auxiliary natural gas-fired boiler. It is considered that both systems are necessary for an optimum coupling to the electricity grid. Although thermal storage is an opening issue for DSG technology, it gives an additional degree of freedom for plant performance optimization. Fossil hybridization is also a key element if a reliable electricity production must be guaranteed for a defined time span. Once the yearly parameters of the solar power plant are calculated, the economic analysis is performed, assessing the effect of the solar multiple in the levelized cost of electricity, as well as in the annual natural gas consumption

Conventional Chemotherapy Followed By Consolidation With Autologous Hematopoietic Transplantation vs Chemotherapy Alone In HIV+ Patients With Large B Cell Lymphoma (LBCL) In First Complete Remission (CR). A Retrospective Analysis On Behalf Of The EBMT Lymphoma Working Party And The GESIDA/PETHEMA Registry Of HIV+ Patients With Non-Hodgkin's Lymphoma (NHL)

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Characterization of oral yeasts isolated from healthy individuals attended in different Colombian dental clinics

The aim of this study was to identify the most frequent yeasts in the oral cavity of adult individuals without immune disorders and to associate the presence of these oral yeasts with different characteristics of each individual. Oral rinse samples were obtained from 96 healthy adults and cultured in Sabouraud dextrose agar media and CHROMagar. Yeasts were identified by sequencing the D1/D2 region of the 28S rRNA gene. Probable association among the socio-demographic characteristics, body mass index, family and personal medical history, oral hygiene, tobacco and/or alcohol consumption habits and presence of oral fungi was analyzed. Contingency tables and logistic regression were employed to evaluate possible relationships between the presence of oral fungi and mixed colonization with these variables. 57.3% of the healthy individuals had oral yeasts and 21.8% had mixed colonization. The most prevalent yeasts were Candida albicans (52%), C. parapsilosis (17.9%), and C. dubliniensis (7.57%). Yeasts with most frequently mixed colonization were C. albicans and C. parapsilosis. No relationships were found among the variables analyzed. However, the presence of mixed colonization was related to the presence of dental prostheses (P less than 0.006), dental apparatuses (P=0.016) and O'Leary index (P=0.012). This is the first study that characterized oral yeasts in Colombian healthy individuals, determined the most prevalent oral yeasts C. albicans, C. parapsilosis and C. dublinensis and an association of mixed colonization with the use of dental prostheses and aparatology and poor hygiene. © 2019 by the Journal of Biomedical Research

Clustering of Dietary Patterns and Lifestyles among Spanish Children in the EsNuPI Study

Dietary patterns (DPs) are known to be tied to lifestyle behaviors. Understanding DPs and their relationships with lifestyle factors can help to prevent children from engaging in unhealthy dietary practices. We aimed to describe DPs in Spanish children aged 1 to <10 years and to examine their associations with sociodemographic and lifestyle variables. The consumption of toddler and young children milk formulas, enriched and fortified milk within the Spanish pediatric population is increasing, and there is a lack of evidence whether the consumption of this type of milk is causing an impact on nutrient intakes and if they are helping to reach the nutrient recommendations. Within the Nutritional Study in the Spanish Pediatric Population (EsNuPI), we considered two study cohorts and three different age groups in three year-intervals in each of them. The study cohort included 740 children in a representative sample of the urban non-vegan Spanish population and 772 children in a convenience cohort of adapted milk consumers (AMS) (including follow-on formula, toddler’s milk, growing up milk, and fortified and enriched milks) who provided information about sociodemographics, lifestyle, and dietary habits; a food frequency questionnaire was used for the latter. Principal component analysis was performed to identify DPs from 18 food groups. Food groups and sociodemographic/lifestyle variables were combined through a hierarchical cluster algorithm. Three DPs predominated in every age group and study sample: a palatable energy-dense food dietary pattern, and two Mediterranean-like DPs. However, children from the AMS showed a predominant dietary pattern markedly related to the Mediterranean diet, with high consumption of cereals, fruits and vegetables, as well as milk and dairy products. The age of children and certain lifestyle factors, namely level of physical activity, parental education, and household income, correlated closely with the dietary clusters. Thus, the findings provide insight into designing lifestyle interventions that could reverse the appearance of unhealthy DPs in the Spanish child population

Visualization of fidaxomicin association with the exosporium layer of Clostridioides difficile spores

Indexación ScopusBackground: Fidaxomicin has novel pharmacologic effects on C. difficile spore formation including outgrowth inhibition and persistent spore attachment. However, the mechanism of fidaxomicin attachment on spores has not undergone rigorous microscopic studies. Materials & methods: Fidaxomicin attachment to C. difficile spores of three distinct ribotypes and C. difficile mutant spores with inactivation of exosporium or spore-coat protein-coding genes were visualized using confocal microscopy with a fidaxomicin-bodipy compound (green fluorescence). The pharmacologic effect of the fidaxomicin-bodipy compound was determined. Confocal microscopy experiments included direct effect on C. difficile wild-type and mutant spores, effect of exosporium removal, and direct attachment to a comparator spore forming organism, Bacillus subtilis. Results: The fidaxomicin-bodipy compound MIC was 1 mg/L compared to 0.06 mg/L for unlabeled fidaxomicin, a 16-fold increase. Using confocal microscopy, the intracellular localization of fidaxomicin into vegetative C. difficile cells was observed consistent with its RNA polymerase mechanism of action and inhibited spore outgrowth. The fidaxomicin-bodipy compound was visualized outside of the core of C. difficile spores with no co-localization with the membrane staining dye FM4-64. Exosporium removal reduced fidaxomicin-bodipy association with C. difficile spores. Reduced fidaxomicin-bodipy was observed in C. difficile mutant spores for the spore surface proteins CdeC and CotE. Conclusion: This study visualized a direct attachment of fidaxomicin to C. difficile spores that was diminished with mutants of specific exosporium and spore coat proteins. These data provide advanced insight regarding the anti-spore properties of fidaxomicin. © 2021 The Authorshttps://www-sciencedirect-com.recursosbiblioteca.unab.cl/science/article/pii/S1075996421000354?via%3Dihu

Análisis preliminar del efecto de las oscilaciones climáticas sobre la condición física de la melva (Auxis rochei) post-reproductora en el Mar de Alborán

The Mediterranean Sea is considered by several authors as a hot-spot of Climate Oscillation, such as the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO). However, information about the effect of the climate oscillations on the fitness of the species is still scarce. In this context, bullet tuna is an important migratory species with a substantial socio-economical value, whose fisheries might be affected by the effect of certain climatological conditions. In fact, these atmospheric oscillations trigger a chain of hydrodynamic events, leading a change on the timing, destinations, and success of the migratory species in their search for spawning grounds. This study relies on the hypothesis of a correlation between the physical condition of the post-spawning bullet tuna and climate oscillation indexes. For that purpose, 151 individuals of bullet tuna, Auxis rochei, were collected in the traps of Ceuta (Alboran Sea) during three different years, (1983, 1984 and 2014). The physical condition index was calculated, and later statistically correlated with the climate oscillation indexes proposed. Significant differences were found between the physical condition of A. rochei and the average accumulated NAO index. Moreover, for age class 3+ we obtained a significant correlation with atmospheric oscillations.Postprin

Early lung cancer detection using spiral computed tomography and positron emission tomography

RATIONALE: Lung cancer screening using computed tomography (CT) is effective in detecting lung cancer in early stages. Concerns regarding false-positive rates and unnecessary invasive procedures have been raised. OBJECTIVE: To study the efficiency of a lung cancer protocol using spiral CT and F-18-fluorodeoxyglucose positron emission tomography (FDG-PET). METHODS: High-risk individuals underwent screening with annual spiral CTs. Follow-up CTs were done for noncalcified nodules of 5 mm or greater, and FDG-PET was done for nodules 10 mm or larger or smaller (> 7 mm), growing nodules. RESULTS: A total of 911 individuals completed a baseline CT study and 424 had at least one annual follow-up study. Of the former, 14% had noncalcified nodules of 5 mm or larger, and 3.6% had nodules of 10 mm or larger. Eleven non-small cell lung cancers (NSCLC) and one small cell lung cancer (SCLC) were diagnosed in the baseline study (prevalence rate, 1.32%), and two NSCLCs in the annual study (incidence rate, 0.47%). All NSCLCs (92% of prevalence cancers) were diagnosed in stage I (12 stage IA, 1 stage IB). FDG-PET was helpful for the correct diagnosis in 19 of 25 indeterminate nodules. The sensitivity, specificity, positive predictive value, and negative predictive value of FDG-PET for the diagnosis of malignancy were 69, 91, 90, and 71%, respectively. However, the sensitivity and negative predictive value of the screening algorithm, which included a 3-month follow-up CT for nodules with a negative FDG-PET, was 100%. CONCLUSION: A protocol for early lung cancer detection using spiral CT and FDG-PET is useful and may minimize unnecessary invasive procedures for benign lesions

New trends on the numerical representability of semiordered structures

[EN] We introduce a survey, including the historical back-ground, on different techniques that have recently been issued in the search for a characterization of the representability of semiordered structures, in the sense of Scott and Suppes, by means of a real-valued function and a strictly positive threshold of discrimination.This work has been supported by the research projects MTM2007-62499, ECO2008-01297, MTM2009-12872-C02-02 and MTM2010-17844 (Spain)Abrísqueta, F.; Campión, M.; Catalán, R.; De Miguel, J.; Estevan, A.; Induráin, E.; Zudaire, M.... (2012). New trends on the numerical representability of semiordered structures. Mathware & Soft Computing Magazine. 19(1):25-37. http://hdl.handle.net/10251/57632S253719

Segregación espacial por sexo de la tintorera en el Atlántico Este y

The main aim of present study was to analyze the spatial and temporal trends segregation by sex of blue shark (Prionace glauca) in the Eastern Atlantic and Western Mediterranean Sea from the individual bycatches by Spanish surface longline fleet. Our results indicate significant differences in the use of space between males and females. Thus, in low latitudes, within the observed range, sharks are mixed, but from North 38 degree of latitude tend to segregate. In the case of length, a similar pattern is observed, in low longitude sexes appear overlapped, and while to high longitude tend to appear segregated. All these results suggested segregation by sex in the Mediterranean where sharks are grouped in single-sex schools.Postprin