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Background: We aim to investigate the effects of the Bruton’s tyrosine kinase (BTK) inhibitor remibrutinib on human in vitro cell activation induced by serum obtained from chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU) patients. Methods: 22 patients with CSU (mean age 52 years, 27% women) and 22 with CIndU (46 years, 27% women) were included. A sex-equivalent control group was enrolled. Total IgE serum levels and the FcεR1a expression on blood basophils were determined before the initiation of omalizumab therapy. Patients were then classified as responders or non-responders to anti-IgE therapy, according to their clinical data and IgE and FcεR1a receptor expression. Mast cell generation and stimulation and basophil stimulation were performed. Flow cytometry was used to analyze samples. Percentage of activation, degranulation and inhibition in basophils and mast cells are studied. Results: Main results show that remibrutinib inhibits mast cells and basophil degranulation induced by IgE cross-linking. Also, serum from patients induced a greater degranulation of mast cells and basophils compared to controls. We found that activation of mast cells and basophils by patient sera was not related to omalizumab responsiveness. Conclusion: Our results show that remibrutinib is able to inhibit the degranulation of human basophils and mast cells in vitro, independently of the patient’s expression of FcεR1 expression and response to omalizumab.

Consensus about the definition and classification of "plaque" in mycosis fungoides is lacking.To delineate a comprehensive view on how the "plaque" entity is defined and managed in clinical practice; to evaluate whether the current positioning of plaques in the TNMB classification is adequate.A 12-item survey was circulated within a selected panel of 22 experts (pathologists, dermatologists, hematologists, oncologists), members of the EORTC and International Society for Cutaneous Lymphoma. The questionnaire discussed clinical and histopathological definitions of plaques and its relationship with staging and treatment.Total consensus and very high agreement rates were reached in 33.3% of questions, as all panelists regularly check for the presence of plaques, agree to evaluate the presence of plaques as a potential separate T class, and concur on the important distinction between plaque and patch for the management of early-stage MF. High agreement was reached in 41.7% of questions, since more than 50% of the responders use Olsen's definition of plaque, recommend the distinction between thin/thick plaques, and agree on performing a biopsy on the most infiltrated/indurated lesion. High divergence rates (25%) were reported regarding the possibility of a clinically based distinction between thin and thick plaques and the role of histopathology to plaque definition.The definition of "plaque" is commonly perceived as a clinical entity and its integration with histopathological features is generally reserved to specific cases. To date, no consensus is achieved as for the exact definition of thin and thick plaques and current positioning of plaques within the TNMB system is considered clinically inadequate. Prospective studies evaluating the role of histopathological parameters and other biomarkers, as well as promising diagnostic tools, such as US/RM imaging and high throughput blood sequencing, are much needed to fully integrate current clinical definitions with more objective parameters.

Background Problem-based learning (PBL) is a pedagogical approach that shifts the role of the teacher to the student (student-centered) and is based on self-directed learning. Although PBL has been adopted in undergraduate and postgraduate medical education, the effectiveness of the method is still under discussion. The author’s purpose was to appraise available international evidence concerning to the effectiveness and usefulness of PBL methodology in undergraduate medical teaching programs. Methods The authors applied the Arksey and O’Malley framework to undertake a scoping review. The search was carried out in February 2021 in PubMed and Web of Science including all publications in English and Spanish with no limits on publication date, study design or country of origin. Results The literature search identified one hundred and twenty-four publications eligible for this review. Despite the fact that this review included many studies, their design was heterogeneous and only a few provided a high scientific evidence methodology (randomized design and/or systematic reviews with meta-analysis). Furthermore, most were single-center experiences with small sample size and there were no large multi-center studies. PBL methodology obtained a high level of satisfaction, especially among students. It was more effective than other more traditional (or lecture-based methods) at improving social and communication skills, problem-solving and self-learning skills. Knowledge retention and academic performance weren’t worse (and in many studies were better) than with traditional methods. PBL was not universally widespread, probably because requires greater human resources and continuous training for its implementation. Conclusion PBL is an effective and satisfactory methodology for medical education. It is likely that through PBL medical students will not only acquire knowledge but also other competencies that are needed in medical professionalism.

Background: The first years of university can be very challenging for students. Previous research has focused on the study of the prevalence of burnout and of psychological distress in medical students. The aim of this study was to investigate the prevalence of psychological symptoms and burnout reported by first-year students, the relationship between these variables and their academic performance, and the differences between health and non-health sciences students. Methods: An observational study with a cross-sectional design was performed. Students of health sciences (medicine, nursing, physiotherapy, psychology), and non-health sciences (biology, social sciences, business management, and engineering) undergraduate programs completed the Brief Symptom Inventory (BSI-18) and the Maslach Burnout Inventory-Student Survey (MBI-SS). Students' grades for the first semester were collected. Results: A sample of 506 students participated. Prevalence of psychological distress was 27.1% and burnout was 7.3%. Academic performance was unaffected in relation to either psychological distress or burnout. Non-health sciences students showed a greater risk of depression. Conclusions: This study provides evidence of the high prevalence of psychological distress in the first year of college. Even when burnout prevalence was low, the results suggest the need to introduce prevention programs to improve the psychological wellbeing of these students. Keywords: burnout; psychological distress; academic performance; mental health; university students; medical students

Solar thermal applications for industries must be designed to operate at high temperature levels; however, the thermal dependency of the accuracy of the incidence angle modifier factorization has not been sufficiently analyzed. In this study, the annually delivered energy based on both factorized and non-factorized incidence angle modifier values were compared with each other. The integration was conducted for a typical meteorological year in Seville and Stockholm. Four collector types were considered: evacuated tube collector, MaReCo collector, Fresnel collector, and CCStaR collector. Thermal process parameters were shown to have an influence on the error made by the factorization approach; however, within the economically viable temperature range of an industrial heat application, this influence is not significant.

The building was built in the late 90s, had a solar installation of 200 m 2 with 4 tanks of DHW and the support of diesel boilers and district heating. After 16 years 25% of the solar collectors are damaged, and some of the storage tanks have rust and lime with leaking. A new design and retrofit is needed to improve the existing installation. New advanced systems are being designed in different phases. The first phase consists of installing new collectors and combisystems tanks. If we add the pool to the system, it is further possible to improve the water management of the building. During this first phase 25% of the solar field will be added with higher efficiency collectors. The estimated energy savings are 14% and the cost savings will be near to 30%.

International audience; AIM: To determine the detection rates, clinical features, and risk factors for lack of registration of alcohol use in medical patients admitted in European hospitals.METHODS: A point-prevalence, cross-sectional, multicenter survey involving 2100 medical inpatients from 43 hospitals from 8 European countries. Patients were screened for current alcohol use, using standardized questionnaires. Alcohol use recording in medical records was assessed.RESULTS: Of the 2100, more than a half reported alcohol use. Significant differences were shown in the prevalence of drinking and the recording rates of alcohol use among the hospitals and countries involved. Overall, 346 patients (16%) fulfilled criteria for alcohol use disorder. Alcohol use was registered in 909 (43%) of medical records, with quantification in 143 (7%). Multivariate analysis showed that women (OR 1.49), older age patients (OR 1.23), patients from the Northern European countries (OR 4.79) and from hospitals with high local alcohol prevalence (OR 1.59) were more likely to have lack of alcohol use registration in their medical files.CONCLUSIONS: A considerable proportion of medical patients admitted in European hospitals fulfill criteria for alcohol use disorders. These patients are frequently overlooked during hospitalization and not appropriately registered in medical records. Women, older patients, and inpatients from European areas with high local alcohol use prevalence are at higher risk associated with a non-recording of alcohol use.

To minimize the experimental effort of assessing biaxial incidence angle characteristics of solar collectors with complex geometries, current testing standards (EN 12975-2, ASHRAE 93, ISO 9806:2013) recommend the factorization method proposed by McIntire (1982). Due to a lack of consensus, researchers in the low and high temperature fields of solar thermal have applied this model in very different ways, either referring to different radiation references (beam radiation on tilted surface vs. direct normal irradiance) or angle projections (θT-θL-domain vs. θT-θi-domain). In this study, the influence of each approach on the factorization error is estimated. Four different collector geometries were considered: compound parabolic collector, maximum reflector collector, linear Fresnel reflector, and fixed-mirror collector (Concentrating Collector with Stationary Reflector, CCStaR V2). The 3D incidence angle modifier surface of each collector was calculated with a sophisticated in-house ray tracing tool and compared with the incidence angle modifier surface constructed by various factorization models. The error was defined as difference between direct normal irradiance weighted annual integration of ray tracing and factorized incidence angle modifier, given the collector’s location and orientation. This allows the deviations to be represented more intuitively by plotting the relative error over latitude. Factorization in the (θT,θi)-domain was shown to constantly yield accurate results even in the case of static collectors.

Solar thermal energy is able to provide a considerable fraction of the medium-temperature energy demand and should be more widely used in specific industrial sectors in 100–250 °C range. For energy collection within this temperature range, solar collector designs usually have optical concentration systems, and therefore, the optical behavior of these devices, especially Incidence Angle Modifier (IAM) term in the standard equations, is of paramount importance to the energy equation balance. In the last few decades various new designs have been developed specifically for industrial applications. At the end of 2013, the new revised version of International Standard ISO 9806 for solar thermal collector test methods was published for worldwide certification. This new Standard unifies all the former American, European and International Standards. However, some solar collector types still do not fit to the Standard testing methodology, in particular solar collectors with variable-geometry. This paper describes the points in International Standard ISO 9806 defined specifically for testing solar collectors with solar tracking and concentration, and present a theoretical model to specify the range of the incidence angles which should be tested on variable-geometry collectors to validate the IAM terms in the energy equation balance. Finally some issues are proposed to extend the scope of the current standards for testing collector designs with variable-geometry, in particular for medium-temperature applications.

The solar trackers are devices used to orientate solar concentrating systems in order to increase the focusing of the solar radiation on a receiver. A solar concentrator with a medium or high concentration ratio needs to be orientated correctly by an accurate solar tracking mechanism to avoid losing the sunrays out from the receiver. Hence, to obtain an appropriate operation, it is important to know the accuracy of a solar tracker in regard to the required precision of the concentrator in order to maximize the collector optical efficiency. A procedure for the characterization of the accuracy of a solar tracker is presented for a single-axis solar tracker. More precisely, this study focuses on the estimation of the positioning angle error of a parabolic trough collector using a direct procedure. A testing procedure, adapted from the International standard IEC 62817 for photovoltaic trackers, was defined. The results show that the angular tracking error was within ±0.4° for this tracker. The optical losses due to the tracking were calculated using the longitudinal incidence angle modifier obtained by ray-tracing simulation. The acceptance angles for various transversal angles were analyzed, and the average optical loss, due to the tracking, was 0.317% during the whole testing campaign. The procedure presented in this work showed that the tracker precision was adequate for the requirements of the analyzed optical system.

Ray-tracing tools are commonly used to optically characterize solar concentrators, but the International Standards used to certify collectors for heating do not allow the use of these tools to analyse the optical behaviour of solar thermal systems. Solar concentrators for the medium temperature range often are of large dimensions and cannot be easily reoriented to the sun without an expensive rotating test platform suggested by the International Standards; therefore, some deficiencies can be detected if the standards procedures are applied to these types of concentrating collectors. In this paper, the use of ray-tracing tools combined with thermal experimental data is proposed to determine the energy balance coefficients by a Weighted Least Square adjustment (WLS). The main advantages of this methodology are that the measurement of the thermal efficiency at normal incidence and solar concentrator reorientation are not required, the optical behaviour of the system can be determined for any position of the sun, and it can be used for in situ measurements for large-scale solar thermal collectors.

The set of optical models that is implemented in ray-tracing software determines the accuracy of its output. A sensitivity analysis was carried out using a powerful in-house program, which provides a large number of surface reflectance and scattering models and in addition, can also run spectral simulations. A linear Fresnel collector was selected as a test case together with the most accurate data that can be found in the literature for the optical properties of its components. The test results indicate that simulations based on constant values, such as mostly provided by the manufacturer, are generally inaccurate and a spectral simulation is not essential for thermal applications.

The determination of the accuracy of a solar tracker used in domestic hot water solar collectors is not yet standardized. However, while using optical concentration devices, it is important to use a solar tracker with adequate precision with regard to the specific optical concentration factor. Otherwise, the concentrator would sustain high optical losses due to the inadequate focusing of the solar radiation onto its receiver, despite having a good quality. This study is focused on the estimation of long-term optical losses due to the tracking error of a low-temperature collector using low-concentration optics. For this purpose, a testing procedure for the incidence angle modifier on the tracking plane is proposed to determinate the acceptance angle of its concentrator even with different longitudinal incidence angles along the focal line plane. Then, the impact of maximum tracking error angle upon the optical efficiency has been determined. Finally, the calculation of the long-term optical error due to the tracking errors, using the design angular tracking error declared by the manufacturer, is carried out. The maximum tracking error calculated for this collector imply an optical loss of about 8.5%, which is high, but the average long-term optical loss calculated for one year was about 1%, which is reasonable for such collectors used for domestic hot water.

In order to increase the trust and willingness to invest in concentrating solar collectors, an accurate labeling and certification process is of utmost importance. Today’s collector testing standards specify methods for assessing the thermal performance of most types of fluid heating solar collectors. However, they do not provide an applicable testing procedure for obtaining the incidence angle modifier of large-scale line-focusing collectors. Such collectors need to be tested directly in the field, where optical characterization by conventional methods, such as factorization, fails. This study presents a new approach to obtain the incidence angle modifier by fitting ray-tracing curves to the measured optical efficiency data set. The new method has been tested on a fixed mirror solar concentrator with a mobile focus. Prior to this study, 49 experimental data points have been obtained for the optical efficiency after measuring for four testing days according to the ISO 9806 rules. These experimental data points served as a basis for the fitting procedure to validate the ray-tracing model. Stable optimized solutions of the collector’s optical parameters have been determined within a reasonable computation time scale. From a comparison of the optimized solution to a simplified ray-tracing simulation, it was seen that the weighted root-mean-square error was improved by 27.7%. In conclusion, the proposed procedure overcomes practical hurdles and has many advantages over conventional methods.

Concentrating solar collectors are mentioned in the International Standards, but the general testing methods for solar collectors mentioned cannot easily be applied to such unusual collector designs. In this study, the best optical and thermal model for a variable geometry solar concentrator has been investigated. In the particular case of a collector with a fixed mirror concentrator, the relative position of the receiver with respect to the reflector is not constant during the day, and this variable geometry is not taken into account in the current testing Standards. An optical characterization of the prototype using a ray-tracing program has been performed, and the results have been used as an initial hypothesis to define two thermal models adapted from the European Standard. Those two different models have been compared. The optical results obtained from experiments have been compared to ray-tracing simulation results, and they have been found to be quite similar, considering the measurement uncertainties. This validation procedure of the optical simulation could be an important point to be taken into account in a future Standard revision for variable geometry collector types for which the normal incidence is not easy to obtain.

Raquel Pascual , Gemma Prieto , M. Rosario Taco c y Ramon Pujol Farriols * a Servicio de Neumologia, Hospital Universitari de Bellvitge, L’Hospitalet de Llobregat, Barcelona, Espana b Servicio de Radiodiagnostico, Hospital Universitari de Bellvitge, L’Hospitalet de Llobregat, Barcelona, Espana c Servicio de Anatomia Patologica, Hospital Universitari de Bellvitge, L’Hospitalet de Llobregat, Barcelona, Espana d Servicio de Medicina Interna, Hospital Universitari de Bellvitge, L’Hospitalet de Llobregat, Barcelona, Espana

We investigate the absorptance and the power conversion efficiency of a perovskite thin-film solar cell at a specular and Lambertian reflection on the cell's back-surface reflector. The analysis is done by means of the Monte-Carlo ray tracing simulations, complemented by the transfer-matrix method to account for the interference phenomenon in the local generation rate G ( z ) of carriers inside the semiconductor. This function is employed further in the transport equations to calculate the current-voltage characteristics of the cell. Taking the perovskite absorber CH3NH3PbI3 as an example, we analyse its efficiency, altering the absorber thickness in the interval 50 ÷ 1000 nm. We find that in the cell ( ∼ 200 nm) the enhanced photon absorption due to the Lambertian reflection yields the efficiency increase on 2.2% as opposed to the specular reflection case. Moreover, the maximum efficiency, obtained for the perovskite layer of the thickness ∼ 150 nm, exceeds the one obtained for the perovskite layer of the thickness ∼ 500 nm with the specular reflection.

The Curved Slats Fixed Mirror Solar Concentrator (CSFMSC) is a solar concentrator with a static reflector and a moving receiver. An optical analysis using ray-tracing tools was presented in a previous study in function of three design parameters: the number of mirrors N, the ratio of focal length and reflector width F/W, and the aperture concentration Ca. However, less is known about the thermal behavior of this geometry. In this communication, the integrated thermal output of the CSFMSC has been determined in order to find the optimal values for the design parameters at a working temperature of 200 °C. The results were obtained for three different climates and two axial orientations (North–South, and East–West). The results show that CSFMSC can produce heat at 200 °C with an annual thermal efficiency of 41, 47, and 51%, dependent of the location considered (Munich, Palma de Mallorca, and Cairo). The best FMSC geometries in function of the design parameters are exhibited for medium temperature applications.

Background: Poor vitamin D status, i.e. low serum levels of 25-hydroxyvitamin D [25(OH)D], is common in the general population. Prospective epidemiologic data on the association between vitamin D and mortality in oldest old subjects are limited. Objective: This study aimed to determine whether 25(OH)D concentrations were prospectively and independently associated with cardiovascular disease (CVD) mortality and all-cause mortality in oldest old subjects. Methods: A total of 312 subjects aged 85 years old at baseline (Octabaix study) were followed for 3 years. Sociodemographic and overall geriatric assessment data were collected. Serum 25(OH)D concentrations were used to assess vitamin D status. Data on overall and cardiovascular mortality were collected. Results: The mean serum 25(OH)D levels were 28 ± 30 ng/ml. During the follow-up period, 58 subjects (18.5%) died. Twenty-five of the deaths (8%) were related to CVD. There were no differences in mortality rates according to the different quartiles of vitamin D (p = 0.41 for total mortality and p = 0.86 for CVD mortality). Conclusion: In community-dwelling oldest old subjects, serum 25(OH)D levels were not associated with overall or CVD mortality after a 3-year follow-up.

Medium temperature collectors will play an important role in the development of process heat applications. Nevertheless, the assessment and comparison of collectors based on different technologies is not yet straight forward from the information currently provided by most manufacturers. It is shown that it is not possible to draw conclusions about the thermal performance of a given collector based on its efficiency curve alone. Therefore a simulation program for three different collector technologies was carried out for 995 locations and weather conditions at 8 working temperature levels ranging from 100 °C to 310 °C. After an analysis of the different parameters affecting collector performance a novel contour chart format is presented.

Purpose Following the detection of an anomaly on Octavius4D pre-treatment QA results for some patients, an investigation to determine its origin was conducted. A problem was found on the angular measurements performed by the inclinometer. The aim of this work is to study the influence of the angular accuracy on Octavius4D results and the ability of the Octavius4D system to detect angular deviations. Methods Measurements were performed using Octavius4D modular system and analysed using Verisoft 7.0 (PTW-Freiburg, Freiburg, Germany). Measurements performed using the malfunctioning inclinometer for 61 patients undergoing VMAT treatments were compared with the same measurements carried out using a new inclinometer. Two different locations were analysed: 40 prostates and 21 pelvises (15 of them were prostates with SIB and 6 of them were gynaecologic pathologies). 3D gamma analysis was computed over the entire volume with acceptance criteria of 3% dose difference and 3 mm distance to agreement. 2%-2 mm gamma test was also calculated. Dose differences were calculated referenced to the maximum dose in calculated volume and the threshold considered was 10% of the maximum dose. The angular lectures of the inclinometer were obtained from .xcc raw files. Results Mean angle differences at 180 degrees (where the greatest difference was observed) are 2.25° for prostates and 2.21° for pelvises. In several cases, the 3%-3 mm gamma criterion does not show any difference between measurements carried out using both inclinometers. The 2%-2 mm gamma criterion leads to a mean difference of 1.71% for prostates and 4.04% for pelvises. In all cases 3%-3 mm gamma passing rates were greater than 95%, making difficult to identify this problem by only applying this criterion. It is observable a dependence of the results on the symmetry of the dose distribution. PTVs comprising only the prostate which are highly symmetrical had lesser variations than more complex treatments. Conclusions 2% dose difference and 2 mm distance to agreement criterion showed better ability to find angular differences when performing gamma analysis for VMAT treatments. This can be potentially used to discover problems in gantry position but a further analysis must be performed.

Ray-Tracing software tools have been widely used in the optical design of solar concentrating collectors. In spite of the ability of these tools to assess the geometrical and material aspects impacting the optical performance of concentrators, their use in combination with experimental measurements in the framework of collector testing procedures as not been implemented, to the date, in none of the current solar collector testing standards. In the latest revision of ISO9806 an effort was made to include linear focusing concentrating collectors but some practical and theoretical difficulties emerged. A Ray-Tracing analysis could provide important contributions to overcome these issues, complementing the experimental results obtained through thermal testing and allowing the achievement of more thorough testing outputs with lower experimental requirements. In order to evaluate different available software tools a comparison study was conducted. Taking as representative technologies for line-focus concentrators the Parabolic Trough Collector and the Linear Fresnel Reflector Collector, two exemplary cases with predefined conditions – geometry, sun model and material properties – were simulated with different software tools. This work was carried out within IEA/SHC Task 49 “Solar Heat Integration in Industrial Processes”.