Comparative energetic assessment of methanol production from CO₂: chemical versus electrochemical process

Emerging emission-to-liquid (eTL) technologies that produce liquid fuels from CO₂ are a possible solution for both the global issues of greenhouse gas emissions and fossil fuel depletion. Among those technologies, CO₂ hydrogenation and high-temperature CO₂ electrolysis are two promising options suitable for large-scale applications. In this study, two CO₂ -to-methanol conversion processes, i.e., production of methanol by CO₂ hydrogenation and production of methanol based on high-temperature CO₂ electrolysis, are simulated using Aspen HYSYS. With Aspen Energy Analyzer, heat exchanger networks are optimized and minimal energy requirements are determined for the two different processes. The two processes are compared in terms of energy requirement and climate impact. It is found that the methanol production based on CO₂ electrolysis has an energy efficiency of 41%, almost double that of the CO₂ hydrogenation process provided that the required hydrogen is sourced from water electrolysis. The hydrogenation process produces more CO₂ when fossil fuel energy sources are used, but can result in more negative CO₂ emissions with renewable energies. The study reveals that both of the eTL processes can outperform the conventional fossil-fuel-based methanol production process in climate impacts as long as the renewable energy sources are implemented

Hospitalizations due to rotavirus gastroenteritis in Catalonia, Spain, 2003-2008

BACKGROUND: Rotavirus is the most common cause of severe gastroenteritis among young children in Spain and worldwide. We evaluated hospitalizations due to community and hospital-acquired rotavirus gastroenteritis (RVGE) and estimated related costs in children under 5 years old in Catalonia, Spain. RESULTS: We analyzed hospital discharge data from the Catalan Health Services regarding hospital admissions coded as infectious gastroenteritis in children under 5 for the period 2003-2008. In order to estimate admission incidence, we used population estimates for each study year published by the Statistic Institut of Catalonia (Idescat). The costs associated with hospital admissions due to rotavirus diarrhea were estimated for the same years. A decision tree model was used to estimate the threshold cost of rotavirus vaccine to achieve cost savings from the healthcare system perspective in Catalonia. From 2003 through 2008, 10655 children under 5 years old were admitted with infectious gastroenteritis (IGE). Twenty-two percent of these admissions were coded as RVGE, yielding an estimated average annual incidence of 104 RVGE hospitalizations per 100000 children in Catalonia. Eighty seven percent of admissions for RVGE occurred during December through March. The mean hospital stay was 3.7 days, 0.6 days longer than for other IGE. An additional 892 cases of presumed nosocomial RVGE were detected, yielding an incidence of 2.5 cases per 1000 child admissions. Total rotavirus hospitalization costs due to community acquired RVGE for the years 2003 and 2008 were 431,593 and 809,224 €, respectively. According to the estimated incidence and hospitalization costs, immunization would result in health system cost savings if the cost of the vaccine was 1.93 € or less. At a vaccine cost of 187 € the incremental cost per hospitalization prevented is 195,388 € (CI 95% 159,300; 238,400). CONCLUSIONS: The burden of hospitalizations attributable to rotavirus appeared to be lower in Catalonia than in other regions of Spain and Europe. The relatively low incidence of hospitalization due to rotavirus makes rotavirus vaccination less cost-effective in Catalonia than in other areas with higher rotavirus disease burden

Approximate Hermitian-Yang-Mills structures and semistability for Higgs bundles. II: Higgs sheaves and admissible structures

We study the basic properties of Higgs sheaves over compact K\"ahler manifolds and we establish some results concerning the notion of semistability; in particular, we show that any extension of semistable Higgs sheaves with equal slopes is semistable. Then, we use the flattening theorem to construct a regularization of any torsion-free Higgs sheaf and we show that it is in fact a Higgs bundle. Using this, we prove that any Hermitian metric on a regularization of a torsion-free Higgs sheaf induces an admissible structure on the Higgs sheaf. Finally, using admissible structures we proved some properties of semistable Higgs sheaves.Comment: 18 pages; some typos correcte

Prospective primary teachers' conceptions about Sciece teaching : ideas resistant to change

Our interest in this work is to develop and implement a Likert-scale questionnaire on primary science teaching. We performed a study with a sample of 404 students in Preservice Primary Education enrolled in a Science Methods Course at the University of Seville. To this end, we designed and validated a 6-point Likertscale questionnaire on which the individual prospective teachers expressed their degree of agreement or disagreement with a series of statements about science teaching and learning in Primary Education. In drafting the statements, we took into account two basic referents: (i) the usual level at which our students begin (starting level, as defined by previous studies with small samples), which coincides with a transmissive perspective on science education (Traditional Model); and (ii) the target levels that we consider desirable, consistent with inquiry based science education (Inquiry-Based Model). The results indicated that the prospective teachers were in agreement with inquiry-based science education, although there co-existed deeply rooted traditional ideas

Nonlinear dynamics of Bose-condensed gases by means of a low- to high-density variational approach

We propose a versatile variational method to investigate the spatio-temporal dynamics of one-dimensional magnetically-trapped Bose-condensed gases. To this end we employ a \emph{q}-Gaussian trial wave-function that interpolates between the low- and the high-density limit of the ground state of a Bose-condensed gas. Our main result consists of reducing the Gross-Pitaevskii equation, a nonlinear partial differential equation describing the T=0 dynamics of the condensate, to a set of only three equations: \emph{two coupled nonlinear ordinary differential equations} describing the phase and the curvature of the wave-function and \emph{a separate algebraic equation} yielding the generalized width. Our equations recover those of the usual Gaussian variational approach (in the low-density regime), and the hydrodynamic equations that describe the high-density regime. Finally, we show a detailed comparison between the numerical results of our equations and those of the original Gross-Pitaevskii equation.Comment: 11 pages, 12 figures, submitted to Phys. Rev. A, January 200

Accuracy of the tuberculosis point-of-care Alere determine lipoarabinomannan antigen diagnostic test using α-mannosidase treated and untreated urine in a cohort of people living with HIV in Guatemala

BACKGROUND: Improved point-of-care diagnostic tests for tuberculosis (TB) in severe immune suppressed people living with HIV (PLWH) are needed to decrease morbidity and mortality outcomes. The aim of the study is to evaluate the performance of the lipoarabinomannan antigen test (LAM-test) with and without α-mannosidase pre-treated urine in a cohort of PLWH in primary care clinics in Guatemala. We further determined TB incidence, and mortality rates and its risk factors in PLWH with TB symptoms. METHODS: Prospective longitudinal study of PLWH with TB symptoms. Urine samples were collected at 2 HIV sites to test the sensitivity of the LAM-test in urine with and without α-mannosidase pre-treatment. A composite reference standard of either a positive Mycobacterium tuberculosis complex culture and/or GeneXpert RESULTS: The overall sensitivity of the LAM-test was of 56.1% with 95% CI of (43.3-68.3). There were no differences in the LAM-test sensitivity neither by hospital nor by CD4 T cell values. LAM-test sensitivity in PLWH with \u3c 200 CD4 T cells/µl was of 62.2% (95% CI 46.5-76.2). There were no significant differences in sensitivity when comparing LAM-test results obtained from untreated vs. α-mannosidase treated urine [55.2% (95% CI 42.6-67.4) vs. 56.9% (95% CI 44-69.2), respectively]. TB incidence in our cohort was of 21.4/100 person years (PYs) (95% CI 16.6-27.6), and mortality rate was of 11.1/100 PYs (95% CI 8.2-15.0). Importantly, PLWH with a positive LAM-test result had an adjusted hazard ratio (aHR) of death of 1.98 (1.0-3.8) with a significant p value of 0.044 when compared to PLWH with a negative LAM-test result. CONCLUSIONS: In this study, α-mannosidase treatment of urine did not significantly increase the LAM-test performance, however; this needs to be further evaluated in a large-scale study due to our study limitations. Importantly, high rates of TB incidence and mortality were found, and a positive LAM-test result predicted mortality in PLWH with TB clinical symptoms

Uncovering tumour heterogeneity through PKR and nc886 analysis in metastatic colon cancer patients treated with 5-FU-based chemotherapy

Colorectal cancer treatment has advanced over the past decade. The drug 5-fluorouracil is still used with a wide percentage of patients who do not respond. Therefore, a challenge is the identification of predictive biomarkers. The protein kinase R (PKR also called EIF2AK2) and its regulator, the non-coding pre-mir-nc886, have multiple effects on cells in response to numerous types of stress, including chemotherapy. In this work, we performed an ambispective study with 197 metastatic colon cancer patients with unresectable metastases to determine the relative expression levels of both nc886 and PKR by qPCR, as well as the location of PKR by immunohistochemistry in tumour samples and healthy tissues (plasma and colon epithelium). As primary end point, the expression levels were related to the objective response to first-line chemotherapy following the response evaluation criteria in solid tumours (RECIST) and, as the second end point, with survival at 18 and 36 months. Hierarchical agglomerative clustering was performed to accommodate the heterogeneity and complexity of oncological patients\u27 data. High expression levels of nc886 were related to the response to treatment and allowed to identify clusters of patients. Although the PKR mRNA expression was not associated with chemotherapy response, the absence of PKR location in the nucleolus was correlated with first-line chemotherapy response. Moreover, a relationship between survival and the expression of both PKR and nc886 in healthy tissues was found. Therefore, this work evaluated the best way to analyse the potential biomarkers PKR and nc886 in order to establish clusters of patients depending on the cancer outcomes using algorithms for complex and heterogeneous data

The determinants of social CRM entrepreneurship : An institutional perspective

Despite a growing interest in social media adoption by corporations, there is minimal knowledge about the drivers of social customer relationship management (SCRM). This study examines the determinants of SCRM entrepreneurship from an institutional perspective and specifically from the banking sector. Data on 19 banks were obtained from 183 responses to a questionnaire. These data were analyzed using Partial Least Square (PLS) path modeling. The findings show that organizational and technological contexts have a significant positive impact on SCRM entrepreneurship. The results also reveal a significant impact of institutional normative and coercive pressures on SCRM entrepreneurship. The findings of this study provide researchers and practitioners with a deeper understanding of how external institutional pressures and internal organizational and technological contexts can interact to create SCRM entrepreneurship. Furthermore, this study contributes to knowledge about the motivations and methods of SCRM adoption and evaluation

Data From Erasmus+ Project Results Platform

Proceedings TEEM 2020: Eighth International Conference on Technological Ecosystems for Enhancing Multiculturality.[EN]Collecting data from Erasmus+ projects related to eLearning and the associated methodologies in order to detect those that have been identified as good practice or success story could be very useful in order to help teachers to define success projects in that field. In order to compile projects of interest, we have the Erasmus+ Project Results Platform, which has a very useful information database to locate educational projects that have been funded by the European Union. This database compiles European educational projects that have been developed in Erasmus+ and also in previous programs such as Lifelong Learning Programme since 2007. The advantage of using this tool is that it has a search engine that allows you to search by keywords and has different criteria to filter. It also allows you to export up to a maximum of 1000 projects per search in excel format with basic data from the filtered projects. Therefore, using this tool is key to be able to identify good practices in European educational projects that serve as a reference to find the parameters useful for learning improvement. This article presents the main data collected from the analysis of educational projects that are connected with eLearning and related methodologies in the aforementioned platform. It also defines which ones will be selected to be able to address an adequate analysis that is manageable to carry out the definition of a methodological guide. As a result of the initial analysis, it is considered appropriate to carry out a review of the projects linked to eLearning in KA1 and KA2 actions that have more than 50 projects connected to this topic, involving educational centers, and that are labelled as good practice and / or success story. With the projects that meet these criteria, there is enough information to achieve the objectives of the research in order to be able to design a methodological guide with the key aspects for implementing eLearning projects

Nutritional status and physical condition in active vs. sedentary elderly people

El objetivo del estudio fue conocer la relación entre el estado nutricional, la adherencia a la dieta mediterránea y el nivel de condición física de personas mayores. Participaron 168 personas mayores de 65 años (grupo control=84 personas activas y grupo experimental=84 personas sedentarias). La adherencia a la dieta mediterránea fue medida con el cuestionario MEDIS-FFQ, el nivel de práctica de actividad física mediante una pregunta creada a tal efecto, y las diferentes pruebas físicas con los instrumentos específicos. Los resultados revelaron que el 63.1% manifestó baja adherencia a la dieta mediterránea y el 34.5% alta, teniendo los sujetos sedentarios mayor adherencia que los activos (p≤0.05; 46.4% vs. 22.6%). Los sujetos activos tienen mejor condición física que los sedentarios (p≤0.001). Por tanto, la mayor parte de las personas mayores deben incrementar su adherencia a la dieta mediterránea y la práctica de actividad física como mecanismo de mejora de su saludThe objective of the study was to know the relationship between nutritional status, adherence to the Mediterranean diet and the level of physical displacement of older people. 168 people older than 65 years participated (control group = 84 active people and experimental group = 84 sedentary people). Adherence to the Mediterranean diet was measured with the MEDIS-FFQ questionnaire, the level of physical activity practice through a question created for that purpose, and the different physical tests with the specific instruments. The results revealed that 63.1% showed low adherence to the Mediterranean diet and 34.5% high, according to the sedentary subject’s greater adherence than the active ones (p≤0.05, 46.4% versus 22.6%). Active subjects have better physical income than sedentary people (p≤0.001). Therefore, most elderly people want to increase their adherence to the Mediterranean diet and the practice of physical activity as a mechanism to reduce their healt