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A better understanding of why and how pollutant emissions from compression ignition engines are produced is one of the strategies to reduce them, and to achieve this it is important to understand what happens in the fuel injection inside the combustion chamber and in the combustion process. Experimentally, it is difficult to analyse the fuel spray right at the initial moments when it enters the combustion chamber due to its high velocity. These initial moments of the fuel spray affect its complete development and, consequently, the combustion process inside the chamber. This fact has motivated the approach of this work, in which a parametric study of the spray penetration as a function of variables that can be measured has been proposed. The purpose of this model is to understand which variables of the injection system significantly affect the spray penetration in the initial instants and how they affect it. This study was carried out using diesel and serves as a reference framework for similar studies using pure or blended sustainable advanced fuels. A computational fluid dynamics (CFD) model that determines the spray penetration at initial instants under different injection pressures and nozzle hole diameters is presented in this work. To tune the model, experiments were carried out on an optical engine. The modelled and experimental results exceed 94.8% agreement in all cases studied.

Harvesting residual thermal energy from exhaust gases with thermoelectric generators is one of the paths that are currently being explored to achieve more sustainable and environmentally friendly means of transport. In some cases, thermoelectric generators are installed in a by-pass configuration to regulate the mass flow entering the thermoelectric generator. Some manufacturers are using throttle valves with electromechanical actuators and electronic control in the exhaust pipe to improve techniques for active control of pollutant emissions in reciprocating internal combustion engines, such as the exhaust gas recirculation. The above-mentioned circumstances have motivated the approach of this work: computational fluid dynamics (CFD) modelling of the operation of a throttle valve used for establishing adequate exhaust backpressure conditions to achieve the low pressure exhaust gas recirculation in Euro 6 engines. The aim of this model is to understand the flow control process with these types of valves in order to incorporate them in an exhaust system that will include two thermoelectric generators used to convert residual thermal energy into electrical energy. This work presents a computational model of the flow through the throttle valve under different temperatures and mass flow rates of the exhaust gas with different closing positions. For all cases, the values of the pressure drop were obtained. In all cases studied, the level of agreement between the modelled and experimental results exceeds 90%. The developed model has helped to propose a correlation to estimate the mass flow rate of exhaust gas from easily measurable quantities.

This paper investigates the design of a thermoelectric generator for exhaust gases from internal combustion engines. Experimentally validated CFD methodology was employed. Different issues are studied, such as the influence of the replacement of the exhaust pipe for the TEG, the recirculation produced, and the influence of fins. The results show that an enlarged inlet cone reduces the recirculation and the pressure drop of the TEG, but more heat is lost across the cone walls, reducing the heat available for the thermoelectric modules. Internal straight fins aligned with the flow achieved a 3% increase in heat transfer, did not significantly increase the pressure drop in this type of device, and reduced the effects on pressure of the recirculation, lowering the overall pressure drop by 10%. An energy production of 175.9 W with 16.2 W of pressure drop power losses resulted in a net energy production of 160.7 W. A comparison with a flat-type thermoelectric generator under the same hot source conditions is also provided.

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Lesbian, gay, and bisexual (LGB) people navigate issues of stigma, discrimination, structural barriers, and a history of medical mistrust when seeking healthcare services. Lesbian, gay, bisexual, and transgender (LGBT)-specific clinics and providers offer alternative spaces where these issues may be avoided, but limited research is available on how LGB people utilize these resources. The current study analyzes data from a nationally-representative survey of 1534 LGB people across three age cohorts. Gender, sexual identity, income, proximity to LGBT community health centers, perceived health status, and the total number of lifetime diagnoses are each associated with past utilization of LGBT-specific clinics and providers; interest in future utilization is associated with sexual identity, race/ethnicity, several psychosocial factors, income, a usual source of care, and mental distress. We conclude that LGBT-specific clinics and providers represent an important piece of the healthcare landscape for LGB people but access remains an important barrier to utilization.

LGBT community organizations in the United States have been providing health services since at least the 1970s. However, available explanations for the origins of LGBT health services do not sufficiently explain why health in particular has been so closely and consistently linked to LGBT activism. Little is also known regarding how LGBT health services may have evolved over time with the growing scientific understanding of LGBT health needs.This study begins with a review of the early intersections of sexuality and health that led to an LGBT health movement in the United States, as well as the evolution of LGBT health services over time. Informed by this, an asset map displaying the location and types of services provided by "LGBT community health centers" today in relation to the population density of LGBT people was explored. An online search of LGBT community health centers was conducted between September-December, 2015. Organizational details, including physical addresses and the services provided, were confirmed via an online database of federally-registered non-profit organizations and organizational websites. The locations and types of services provided were analyzed and presented alongside county-level census data of same-sex households using geographic information system (GIS) software ArcGIS for Desktop.LGBT community health centers are concentrated within urban hubs and coastal states, and are more likely to be present in areas with a high density of same-sex couples. LGBT community health centers do not operate in 13 states. The most common health services provided are wellness programs, HIV/STI services, and counseling services.LGBT community health centers have adapted over time to meet the needs of LGBT people. However, significant gaps in service remain in the United States, and LGBT community health centers may require significant transformations going forward in order to continue serving LGBT people.

Las asociaciones de Alzheimer son entidades que tienen enorme resonancia en la sociedad actual y en las próximas décadas, debido a la prevalencia de esta enfermedad, por la enorme necesidad de formación de cuidadores informales y, especialmente, porque como veremos a lo largo de este articulo se hace cada vez más necesario unificar criterios básicos comunes en todas las asociaciones en tomo a programas de formación que ofrecen duración de los programas, equipos interdisciplinarios que los forman, etc. Este estudio ha pretendido estar al corriente del estado actual de la implantación de programas de formación para familiares de enfermos de Alzheimer en las asociaciones dedicadas a ellos. Para ello, la muestra del estudio estuvo compuesta por 24 asociaciones de familiares de Alzheimer en España, administrándose un cuestionario- Entre los resultados más destacados, el 87% de las asociaciones contaban con un programa de formación dirigido a familiares. Existen diferentes criterios en la implantación dependiendo de la zona geográfica en que nos encontremos. Destacando la figura del psicólogo/a como relevante en el desarrollo y puesta en marcha de estas actuaciones. Dichos resultados parecen indicar la necesidad de lograr una unificación de criterios en cuanto a dichos programas, para lograr asi una mayor calidad asistencial y formativa al familiar del enfermo.

The aim of the present study was focused on the determination of the effect of the diameter of the hand-rim of the racing wheelchair on the heart rate and blood lactate produced at the competition speeds. The study was carried out with a world-class athlete, that made a total of 9 series of 5 minutes, at maintained speed, recovering 10 min between series and testing 3 hand-rim (34, 36 and 38cm of diameter) at 3 different speeds (20, 22 and 24 Km/h). Heart rate and blood lactate was measured. An ANOVA was made and we found statistically significant differences (p

A laboratory rearing system in semi-controlled conditions is proposed to facilitate the behavioural rhythms of the edible snail (Helix aspersa) and to produce a high growth rate with low variability. The growth data were used to construct a model for weight estimation based on age. The animals' live weights showed low variability (<17%) and normal distribution. The best model for estimating weight from age is the logistic model, with a high corelation coefficient (>90%), and a high level of significance for the coefficient (P<0.0001). [ABSTRACT FROM AUTHOR]

Soil-transmitted helminths (STH) are a significant public health problem in impoverished communities of tropical and subtropical areas. Improved diagnostic methods are crucial for Neglected Tropical Diseases programs, particularly for S. stercoralis , as traditional methods are inadequate. Thus, it is important to identify the most accurate and efficient methods for the diagnosis of STH. We performed a retrospective study analyzing laboratory data at the Instituto de Investigaciones de Enfermedades Tropicales from 2010 to 2019. The study included data from outpatients referred for stool analysis and public health interventions from urban and rural communities in northern Salta province, Argentina. Samples were included in this analysis if processed through sedimentation/concentration, Baermann, Harada-Mori and McMaster's, with a subgroup that also included Agar plate culture method (APC). Sensitivity was calculated against a composite reference standard. Of the 5625 samples collected, 944 qualified for this analysis, with a prevalence of 11.14% for A. lumbricoides , 8.16% for hookworm, 1.38% for T. trichiura , and 6.36% for S. stercoralis . The sedimentation/concentration method was the most sensitive for A. lumbricoides (96%), compared to the McMaster method, with a sensitivity of 62%. Similarly, for hookworms, sedimentation/concentration was more sensitive than McMaster's, Harada-Mori, and Baermann with sensitivities of 87%, 70%, 43%, and 13%, respectively. Most of these infections were of light intensity. For S. stercoralis , Baermann and sedimentation/concentration methods were the most sensitive, with 70% and 62% respectively, while Harada-Mori was the least sensitive. In a subset of 389 samples also analyzed by the APC, Baermann was more sensitive than APC for detecting S. stercoralis , and both methods were superior to Harada-Mori. Parasitological methods, mostly when used combined, offer adequate opportunities for the diagnosis of STH in clinical and public health laboratories. The incorporation of S. stercoralis into the control strategies of the World Health Organization requires rethinking the current diagnostic approach used for surveys. With sedimentation/concentration and Baermann appearing as the most sensitive methods for this species. Further studies, including implementation assessments, should help in identifying the most adequate and feasible all-STH diagnostic approach., Competing Interests: The authors declare that they have no competing interests., (© 2024 Published by Elsevier Ltd on behalf of World Federation of Parasitologists.)

COVID-19 hospital mortality is higher among older patients through as yet little-known factors. We aimed to assess the effect of frailty (FR), oropharyngeal dysphagia (OD) and malnutrition (MN) on mortality in hospitalized COVID-19 older patients. Prospective cohort study of older patients (>70 years) with COVID-19 admitted to a general hospital from April 2020 to January 2021. Patients were evaluated on admission, discharge and at 1- and 3-months follow up. FR was assessed with FRAIL-VIG, OD with Volume-Viscosity Swallowing Test and MN with GLIM criteria. Clinical characteristics and outcomes, including intra-hospital, 1- and 3-month mortality, were analyzed. 258 patients were included (82.5±7.6 years; 58.9% women); 66.7% had FR (mild 28.7%, moderate 27.1% and severe 10.9%); 65.4%, OD and 50.6%, MN. OD prevalence increased from non-FR patients through the severity levels of FR: mild, moderate and severe (29.8%, 71.6%, 90.0%, 96.2%; p<0.0001, respectively), but not that of MN (50.6%, 47.1%, 52.5%, 56.0%). Mortality over the whole study significantly increased across FR categories (9.3% non-FR; 23.0% mild; 35.7% moderate; 75.0% severe; p<.001). Functionality (Barthel pre-admission, HR=0.983, CI-95%:0.973-0.993; p=0.001), OD (HR=2.953, CI-95%:0.970-8.989; p=0.057) and MN (HR=4.279, CI-95%:1.658-11.049; p=0.003) were independent risk factors for intra-hospital mortality. FR, OD and MN are highly prevalent conditions in older patients hospitalized with COVID-19. Functionality, OD and MN were independent risk factors for intra-hospital mortality.

Wear of the secondary of the welding gun, caused by mechanical fatigue or due to a bad parameterization of the welding points, causes an increase in quality problems such as non-existent welds or a reduced weld nugget size. In addition to quality problems, this defect causes production stoppages that affect the final cost of the manufactured part. Different studies have focused on evaluating the importance of different welding parameters, such as current, in the final quality of the welding nugget. However, few studies have focused on preventing weld command parameters from degrading or changing. This investigation seeks to determine the wear of the secondary circuit to avoid variability in the current supplied to the welding point caused by this defect and the increase in circuit resistance, especially in industrial environments. In this work, a virtual sensor is developed to estimate the resistance of the welding arm based on previous research, which has shown the possibility of detecting secondary wear by analysing the duty cycle of the power circuit. From the data of the virtual sensor, an anomaly detection method based on the Mahalanobis distance is developed. Finally, an integral system for detecting secondary wear of welding guns in real production lines is presented. This system establishes performance thresholds based on the analysis of the Mahalanobis distance distribution, allowing monitoring of the secondary circuit wear condition after each welding cycle. The results obtained show how the system can detect incipient wear in welding guns, regardless of which part of the secondary the wear occurs, improving decision-making and reducing quality problems.

Primary malignant brain tumors are heterogeneous and infrequent neoplasms. Their classification, therapeutic regimen and prognosis have undergone significant development requiring the innovation of an imaging diagnostic. The performance of enhanced magnetic resonance imaging depends on blood-brain barrier function. Several studies have demonstrated the advantages of static and dynamic amino acid PET/CT providing accurate metabolic status in the neurooncological setting. The aim of our single-center retrospective study was to test the primary diagnostic role of amino acid PET/CT compared to enhanced MRI. Emphasis was placed on cases prior to intervention, therefore, a certain natural bias was inevitable. In our analysis for newly found brain tumors 18 F-FET PET/CT outperformed contrast MRI and PWI in terms of sensitivity and negative predictive value (100% vs. 52.9% and 36.36%; 100% vs. 38.46% and 41.67%), in terms of positive predictive value their performance was roughly the same (84.21 % vs. 90% and 100%), whereas regarding specificity contrast MRI and PWI were superior (40% vs. 83.33% and 100%). Based on these results the superiority of 18 F-FET PET/CT seems to present incremental value during the initial diagnosis. In the case of non-enhancing tumors, it should always be suggested as a therapy-determining test.

Electrode misalignment, produced by mechanical fatigue or bad adjustments of the welding gun, leads to an increase in expulsions, deformations and quality problems of the welding joints. Different studies have focused on evaluations of the influence of a misalignment of the electrodes and the final quality of the weld nugget. However, few studies have focused on determining a misalignment of the electrodes to avoid problems caused by this defect, especially in industrial environments. In this paper, a method for performing the condition monitoring of electrode alignment degradation was developed following previous research, which has shown the relationship between the misalignment of short-circuited electrodes and the magnetic field generated by them. This method was carried out by means of a device capable of measuring the magnetic field. Finally, an integral system for the detection of misalignments in real production lines is presented. This system set behavior thresholds based on the experimentation, allowing the condition monitoring of the alignment after each welding cycle.

Resistance spot welding is one of the most widely used metal joining processes in the manufacturing industry, used for structural body manufacturing, railway vehicle construction, electronics manufacturing, battery manufacturing, etc. Due to its wide use, the quality of welded joints is of great importance to the manufacturing industry, as it is critical for ensuring the integrity of finished products, such as car bodies, that withstand high levels of stress. The quality of the welding is influenced both by the programming of the welding and by the good condition of the mechanical part that carries out the welding. These mechanical factors, such as electrode geometry and wear, degrade over time. As the welding points are made, the geometry and properties of the electrodes change, so they undergo a milling process to remove impurities and return them to their initial geometry. Sometimes the milling is deficient, and the electrode continues to wear, causing welding problems such as loose spots and metal spatter. This article presents a method for condition monitoring of the milling process and weld wear based on existing data in real production lines. The use of unsupervised clustering methods is proposed to perform a check by which, using current and resistance data, the electrode wear is grouped. Specifically, a method using multidimensional k-means for the condition monitoring of electrode wear is established. This research gives a real and applicable solution for reducing the quality problems caused by milling defects and electrode wear in the production lines of high-production manufacturing industries, presenting a system for sending alarms based on the behavior of welding variables.

Soil-transmitted-helminth (STH) infections are a persistent global public health problem. Control strategies for STH have been based on the use of mass drug administration (MDA) mainly targeting preschool- and school-aged-children, although there is increasing interest in expanding treatment to include adults and others through community-wide MDA. Coverage assessment is critical to understanding the real effectiveness of albendazole (ALB) treatment in those MDA programs. The work described here aims to (i) evaluate the effect of type of diet (a heavy or light meal) and fasting before ALB treatment on the systemic disposition of ALB and its metabolites in treated human volunteers and (ii) evaluate the potential feasibility of detecting albendazole metabolites in urine. The data reported here demonstrate that the systemic availability of the active ALB-sulfoxide (ALBSO) metabolite was enhanced more than 2-fold after food ingestion (a heavy or light meal). ALB dissolution improvement related to the ingestion of food may modify the amount of drug/metabolites reaching the parasite, affecting drug efficacy and the overall success of MDA strategies. The measurement in urine samples of the amino-ALB-sulfone (NHALBSO 2 ) derivative and ALBSO for up to 96 h suggests that it may be feasible to develop a noninvasive tool to evaluate compliance/adherence to ALB treatment.

Empirically Supported Psychological Treatments for Children and Adolescents: State of the Art., Background: The empirical evidence accumulated on the efficacy, effectiveness, and efficiency of psychotherapeutic treatments in children and adolescents calls for an update. The main goal of this paper objective was to carry out a selective review of empirically supported psychological treatments for a variety of common psychological disorders and problems in childhood and adolescence., Method: A review was carried out of the psychological treatments for different psychological disorders and problems in social-emotional or behavioral adjustment in the child-adolescent population according to the Spanish National Health System (Clinical Practice Guidelines) levels of evidence and degrees of recommendation., Results: The findings suggest that psychological treatments have empirical support for addressing a wide range of psychological problems in these developmental stages. The degree of empirical support ranges from low to high depending on the phenomenon analyzed. The review suggests unequal progress in the different fields of intervention., Conclusions: From this update, psychologists will be able to make informed decisions when implementing those empirically supported treatments to address the problems that occur in childhood and adolescence.

Modern imaging processes, with CT and MRI diagnostics among them, play an increasingly important role in the early diagnosis and determination of the extent and nature of illnesses and the evaluation of their response to therapy. The authors review the technical and technological improvements that have recently been realised in CT and MRI diagnostics and are being adopted in clinical practice. Relying on the results achieved so far, they are analysing the potential for further development. In both modalities, the primary aim is incessant hardware and software upgrades, the implementation of cost-efficient solutions by increasing efficiency and cutting back maintenance and operational costs. The reduction in examination time, the ever-improving image quality and the increased comfort level of the examination environment are of outstanding significance to both the patient and the staff. The interpretation of the generated data is highly dependent on the level of expertise and experience and the knowledge of clinical data and technical opportunities of the person issuing the findings. This process is going to be assisted by artificial intelligence (AI) that the authors also discuss in terms of CT and MRI diagnostics.

Objective: To determine the epidemiological characteristics, treatment, reperfusion strategies and in-hospital adverse events of patients with ST elevation myocardial infarction in Peru., Methods: Observational, prospective multicentre study in patients over 18 years admitted to hospital with a diagnosis of ST elevation myocardial infarction., Results: A total of 396 patients were enrolled in the registry during February 2016 to February 2017. The mean age was 64.9±12 years, and 21% were women. In the first 12h of onset 38% of patients were fibrinolysed, 29% underwent primary PCI, and 33% did not receive any reperfusion. Pharmaco-invasive strategy was used in 12.9% of cases. The fibrinolysis was successful in 65% of patients, and primary PCI success was 82%. The hospital stay was 6 days (IQR 5-10). In-hospital mortality was 10.1%, with the first cause of death being due to cardiogenic shock. The rate of in-hospital re-infarction was 2.2%, and the rate of acute heart failure was 25%. Age>75 years, large infarct size, left ventricular ejection fraction<40%, and absence of negative T waves on post-reperfusion electrocardiogram were independently related to higher in-hospital mortality., Conclusions: In Peru, ST elevation myocardial infarction most frequently affects men between 60-70 years. The most frequent initial reperfusion treatment is fibrinolysis, followed by primary angioplasty, and pharmaco-invasive strategy. The main reason for the lack of administration of reperfusion treatment was the delay from symptoms onset to first medical contact. The most common cause of in-hospital death was cardiogenic shock., (Copyright © 2017 Instituto Nacional de Cardiología Ignacio Chávez. Publicado por Masson Doyma México S.A. All rights reserved.)

Electromagnetic noise absorber sheets have become a solution for solving complex electromagnetic interference (EMI) problems due to their high magnetic losses. This contribution is focused on characterizing a novel structure that is based on an absorber film with a metal layer attached on its top side. Two different absorber compositions were combined with Al and Cu metal layers in order to study the improvement on the performance of these structures, depending on the complex permeability, absorber film thickness, and type of metal. The transmission attenuation power ratio of the absorber films is analyzed and compared to the performance of absorber and metal structures. The measurement procedure is carried out attaching the films into a microstrip line that has been designed based on IEC standard (IEC 62333-2). This test fixture is employed as a transmission line to simulate a general noise path. The performance of absorber composites to filter electromagnetic noise is evaluated through analyzing S 21 and S 11 parameters. This is carried out with the aim of finding out in which conditions the absorption loss is improved when a metal layer is attached. In addition, the possible re-radiation effect, due to the magnetic field that is generated by the eddy currents induced in the metal layer, is examined.

The gap of standardization for conducted and field coupled electromagnetic interferences (EMI) in the 2-150 kHz frequency range can lead to Electromagnetic Compatibility (EMC) problems. This is caused by power systems such as Pulse Width Modulation (PWM) controlled rectifiers, photovoltaic inverters or charging battery units in electric vehicles. This is a very important frequency spectral due to interferences generated in a wide range of devices and, specifically, communication problems in the new technologies and devices incorporated to the traditional grid to convert it into a Smart Grid. Consequently, it is necessary to provide new solutions to attenuate this kind of interference, which involves finding new materials that are able to filter the electromagnetic noise. This contribution is focused on characterizing the performance of a novel material based on nanocrystalline and comparing it to most common material compositions such as MnZn and NiZn. This research is carried out from the point of view of the manufacturing process, magnetic properties and EMI suppression ability. This last item is carried out through two analysis procedures: a theoretical method by determining the attenuation ratio by measuring impedance parameter and proposing a new empirical technique based on measuring directly the insertion loss parameter. Therefore, the main aim of this characterization process is to determine the performance of nanocrystalline compared to traditional cable ferrite compositions to reduce the interferences in this controversial frequency range. From the results obtained, it is possible to deduce that nanocrystalline cable ferrite provides the best performance to filter the electromagnetic noise in the 2-150 kHz frequency range., Competing Interests: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.