bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical Properties, Corrosion Resistance and Bioactivity of Oxide Layers Formed by Isothermal Oxidation of Ti-6Al-7Nb Alloy
Authors: Aniołek Krzysztof , Łosiewicz Bożena , Kubisztal Julian , Osak Patrycja , Stróż Agnieszka , Barylski Adrian , Kaptacz Sławomir
Published: April 2021

Titanium and its alloys are among the most promising biomaterials for medical applications. In this work, the isothermal oxidation of Ti-6Al-7Nb biomedical alloy towards improving its mechanical properties, corrosion resistance, and bioactivity has been developed. The oxide layers were formed at 600, 700, and 800 °C for 72 h. Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), 3D profilometry, and microindentation test, were used to characterize microstructure, surface geometrical structure, and the hardness of the diphase (α + β) Ti-6Al-7Nb alloy after oxidation, respectively. In vitro corrosion resistance tests were carried out in a saline solution at 37 °C using the open-circuit potential method and potentiodynamic measurements. Electronic properties in the air were studied using the Scanning Kelvin Probe (SKP) technique. The bioactivity test was conducted by soaking the alkali- and heat-treated samples in simulated body fluid for 7 days. The presence of apatite was confirmed using SEM/EDS and Fourier Transform Infrared Spectroscopy (FTIR) studies. The thickness of oxide layers formed increased with the temperature growth from 0.25 to 5.48 µm. It was found that with increasing isothermal oxidation temperature, the surface roughness, hardness, corrosion resistance, and contact potential difference increased. The Ti-6Al-7Nb alloy after oxidation revealed the HAp-forming ability in a biological environment.
Changing the Order of Factors Does Not Change the Product but Does Affect Students’ Answers, Especially Girls’ Answers
Authors: Cascella Clelia , Giberti Chiara , Bolondi Giorgio
Published: April 2021

This study is aimed at exploring how different formulations of the same mathematical item may influence students’ answers, and whether or not boys and girls are equally affected by differences in presentation. An experimental design was employed: the same stem-items (i.e., items with the same mathematical content and question intent) were formulated differently and administered to a probability sample of 1647 students (grade 8). All the achievement tests were anchored via a set of common items. Students’ answers, equated and then analysed using the Rasch model, confirmed that different formulations affect students’ performances and thus the psychometric functionality of items, with discernible differences according to gender. In particular, we explored students’ sensitivity to the effect of a typical misconception about multiplication with decimal numbers (often called “multiplication makes bigger”) and tested the hypothesis that girls are more prone than boys to be negatively affected by misconception.
Undergraduate University Education in Internet of Things Engineering in China: A Survey
Authors: Du Bing , Chai Yuke , Huangfu Wei , Zhou Rongjuan , Ning Huansheng
Published: April 2021

To address the problem of a serious Internet of Things (IoT) talent shortage, the Chinese government is encouraging universities and institutions to establish a major in IoT Engineering to train high-level IoT talent. Since 2011, 700 Chinese universities and institutions have established IoT Engineering undergraduate programs. We surveyed the history, status, curriculum, and problems of IoT undergraduate degree programs in China. Based on data collected from faculties, students, and graduates, we found that the IoT Engineering curriculum was an unsystematic patchwork and was deficient in practical platforms. We then provide suggestions for further development and exploration of IoT education by presenting a Technical Knowledge Map of IoT Engineering. This survey work on Chinese IoT education can prompt Chinese educators to reflect on its achievements and problems, which will contribute to IoT talent cultivation worldwide.
E-Shaped H-Slotted Dual Band mmWave Antenna for 5G Technology
Authors: Raheel Kiran , Altaf Ahsan , Waheed Arbab , Kiani Saad Hassan , Sehrai Daniyal Ali , Tubbal Faisel , Raad Raad
Published: April 2021

The aim of this work is to propose a dual band millimeter wave (mmwave) MIMO antenna system for 5G technology. In addition, the arrangement of the antenna elements in an array should be in such a manner that without using the traditional decoupling structures and/or techniques, a reasonable isolation level must be achieved. To demonstrate this, a system consists of four radiating elements that are etched on a 0.508 mm-thick Rogers-5880 substrate. The dielectric constant of the substrate is 2.2 and the loss tangent is 0.0009. Each radiating element consists of three parts; an E-shaped patch, an H-shaped slot within a patch, and a transmission line. The system is resonating at two different mmwave frequencies, i.e., 28 GHz and 38 GHz with a minimum port isolation of 28 dB. The mean measured gain is found to be at 7.1 dBi at 28 GHz and 7.9 dBi at 38 GHz with average efficiency, and envelope correlation coefficient (ECC) of the system at 70%, and 0.0005 respectively. The proposed system is designed and simulated in a full-wave electromagnetic wave software Computer Simulation Technology (CST), fabricated using LPKF D104 milling machine, and measured using R&SZNA67 vector network analyzer. An excellent agreement is observed between the simulated and the measured results and a detailed comparison with the previous works is also presented. Due to attributes such as low-cost, easy to fabricate, and dual-band, it is believed that this system will find its application for future 5G systems.
Deep Item Response Theory as a Novel Test Theory Based on Deep Learning
Authors: Tsutsumi Emiko , Kinoshita Ryo , Ueno Maomi
Published: April 2021

Item Response Theory (IRT) evaluates, on the same scale, examinees who take different tests. It requires the linkage of examinees’ ability scores as estimated from different tests. However, the IRT linkage techniques assume independently random sampling of examinees’ abilities from a standard normal distribution. Because of this assumption, the linkage not only requires much labor to design, but it also has no guarantee of optimality. To resolve that shortcoming, this study proposes a novel IRT based on deep learning, Deep-IRT, which requires no assumption of randomly sampled examinees’ abilities from a distribution. Experiment results demonstrate that Deep-IRT estimates examinees’ abilities more accurately than the traditional IRT does. Moreover, Deep-IRT can express actual examinees’ ability distributions flexibly, not merely following the standard normal distribution assumed for traditional IRT. Furthermore, the results show that Deep-IRT more accurately predicts examinee responses to unknown items from the examinee’s own past response histories than IRT does.
LQR-Based Adaptive Virtual Inertia for Grid Integration of Wind Energy Conversion System Based on Synchronverter Model
Authors: Gil-González Walter , Montoya Oscar Danilo , Escobar-Mejía Andrés , Hernández Jesús C.
Published: April 2021

This paper proposes adaptive virtual inertia for the synchronverter model implemented in a wind turbine generator system integrated into the grid through a back-to-back converter. A linear dynamic system is developed for the proposed adaptive virtual inertia, which employs the frequency deviation and the rotor angle deviation of the synchronverter model as the state variables and the virtual inertia and frequency droop gain as the control variables. In addition, the proposed adaptive virtual inertia uses a linear quadratic regulator to ensure the optimal balance between fast frequency response and wind turbine generator system stress during disturbances. Hence, it minimizes frequency deviations with minimum effort. Several case simulations are proposed and carried out in MATLAB/Simulink software, and the results demonstrate the effectiveness and feasibility of the proposed adaptive virtual inertia synchronverter based on a linear quadratic regulator. The maximum and minimum frequency, the rate change of the frequency, and the integral of time-weighted absolute error are computed to quantify the performance of the proposed adaptive virtual inertia. These indexes are reduced by 46.61%, 52.67%, 79.41%, and 34.66%, in the worst case, when the proposed adaptive model is compared to the conventional synchronverter model.
Wavelet Transform Based Fault Identification and Reconfiguration for a Reduced Switch Multilevel Inverter Fed Induction Motor Drive
Authors: Veerendra Arigela Satya , Shah Akeel A. , Mohamed Mohd Rusllim , Sekhar Chavali Punya , Leung Puiki
Published: April 2021

The multilevel inverter-based drive system is greatly affected by several faults occurring on switching elements. A faulty switch in the inverter can potentially lead to more losses, extensive downtime and reduced reliability. In this paper, a novel fault identification and reconfiguration process is proposed by using discrete wavelet transform and auxiliary switching cells. Here, the discrete wavelet transform exploits a multiresolution analysis with a feature extraction methodology for fault identification and subsequently for reconfiguration. For increasing the reliability, auxiliary switching cells are integrated to replace faulty cells in a proposed reduced-switch 5-level multilevel inverter topology. The novel reconfiguration scheme compensates open circuit and short circuit faults. The complexity of the proposed system is lower relative to existing methods. This proposed technique effectively identifies and classifies faults using the multiresolution analysis. Furthermore, the measured current and voltage values during fault reconfiguration are close to those under healthy conditions. The performance is verified using the MATLAB/Simulink platform and a hardware model.
Economic and Energy Analysis of Building Retrofitting Using Internal Insulations
Authors: Basińska Małgorzata , Kaczorek Dobrosława , Koczyk Halina
Published: April 2021

The energy-saving requirements for most buildings focus on improving the insulation and airtightness of a building’s envelope. In this paper, the authors have investigated the effect of additional internal insulation on energy consumption for heating and cooling in a residential building. Energy performance analyses were conducted for buildings with four internal thermal insulation systems in three locations using the WUFI Plus software. The Global Cost Method and Simply Pay Back Time have been used to assess and compare the economic viability of the retrofit systems. The results show that, in relation to energy, retrofitting with internal wall insulation can be an alternative to traditional external insulation. The assessment of internal insulation for low-energy buildings, however, cannot be conducted based on economic criteria. The usual approach of Simply Pay Back Time has exceptionally long payback time, which is unacceptable. In turn, the Global Cost Method, can only be used to compare the applied materials. With high investment costs, thermo-modernization improvements do not contribute to significant savings. The conditions of thermal comfort and the analysis of temperature and steam pressure play a decisive role in assessing this type of solution.
Design and Experimental Validation of a Single-Stage PV String Inverter with Optimal Number of Interleaved Buck-Boost Cells
Authors: Fesenko Artem , Matiushkin Oleksandr , Husev Oleksandr , Vinnikov Dmitri , Strzelecki Ryszard , Kołodziejek Piotr
Published: April 2021

Increasing converter power density is a problem of topical interest. This paper discusses an interleaved approach of the efficiency increase in the buck-boost stage of an inverter with unfolding circuit in terms of losses in semiconductors, output voltage ripples and power density. Main trends in the power converter development are reviewed. A losses model was designed and used for the proposed solution to find an optimal number of interleaved cells. It describes static and dynamic losses in semiconductor switches for buck and boost mode. The presented calculation results demonstrate the efficiency of the interleaved approach for photovoltaic system. 1 kW power converter prototype was designed with two parallel dc-dc cells for experimental verification of obtained theoretical results. The experimental results confirm theoretical statements.
Hydrogen Purification Performance Optimization of Vacuum Pressure Swing Adsorption on Different Activated Carbons
Authors: Xiao Jinsheng , Mei Ang , Tao Wei , Ma Shuo , Bénard Pierre , Chahine Richard
Published: April 2021

Hydrogen purification is an important part of hydrogen energy utilization. This study aimed to perform hydrogen purification of multi-component gas (H2/CO2/CH4/CO/N2 = 0.79/0.17/0.021/0.012/0.007) by one-column vacuum pressure swing adsorption (VPSA) and pressure swing adsorption (PSA). AC5-KS was selected as the adsorbent for hydrogen purification due to its greater adsorption capacity compared to R2030. Furthermore, VPSA and PSA 10-step cycle models were established to simulate the hydrogen purification process using the Aspen Adsorption platform. The simulation results showed that the hydrogen purification performance of VPSA is better than that of PSA on AC5-KS adsorbent. The effects of feeding time and purging time on hydrogen purity and recovery were also discussed. Results showed that feeding time has a negative effect on hydrogen purity and a positive effect on hydrogen recovery, while purging time has a positive effect on hydrogen purity and a negative effect on hydrogen recovery. By using an artificial neural network (ANN), the relationship between the inputs (feeding time and purging time) and outputs (hydrogen purity and recovery) was established. Based on the ANN, the interior point method was applied to optimize hydrogen purification performance. Considering two optimization cases, the optimized feeding time and purging time were obtained. The optimization results showed that the maximum hydrogen recovery reached 88.65% when the feeding time was 223 s and the purging time was 96 s. The maximum hydrogen purity reached 99.33% when the feeding time was 100 s and the purging time was 45 s.
Effects of Management Practices on Soil Properties and Plant Nutrition in Hay Meadows in Picos de Europa
Authors: Álvarez Judith , Afif Elías , Díaz Tomás E. , García Laura , Oliveira Jose A.
Published: April 2021

Fertilization and mowing affects the physico-chemical properties of soils, as well as the characteristics of the plants growing on them. Changes in the management techniques are causing semi-natural grasslands to disappear all over Europe. These grasslands host a great amount of diversity, thus their conservation is a top priority. This work studies whether the kind of management has an influence on the soil properties and the foliar content in macronutrients in 25 hay meadows located in Picos de Europa (10 in Asturias, 10 in Castilla y León and 5 in Cantabria). Soils at a 0–20 cm depth showed a high content of organic matter and a low C/N ratio. Effective cation exchange capacity was adequate for a texture, which varied from sandy clay loam to loam, with an average clay content of 17%. Mean values of foliar nutrient concentrations showed a deficiency in K. In this study, management practices were shown to affect some properties of the soils, namely pH, sand percentage and exchangeable K and Ca, to different extents. The highest values of pH and exchangeable Ca were significantly correlated with the least intensive management.
Impact of Thermotherapy and Short-Term Storage on Quercus robur L. Acorn Mycobiota and Germination
Authors: Kranjec Orlović Jelena , Drvodelić Damir , Vukelić Marko , Rukavina Matea , Diminić Danko , Oršanić Milan
Published: April 2021

When natural regeneration of Quercus robur stands is hampered by an insufficient acorn yield, human assisted sowing of acorns collected in non-affected stands and stored for some period of time is performed. To inhibit the development of fungi and acorn deterioration during storage, thermotherapy is usually applied by submerging acorns for 2.5 h in water heated to 41 °C. This research aimed to test the effect of four thermotherapy treatments of different durations and/or applied temperatures as well as short-term storage at −1 °C or 3 °C on acorn internal mycobiota and germination. Fungal presence in cotyledons was analyzed in 450 acorns by isolation of mycelia on artificial media, followed by a DNA-based identification. Germination of 2000 acorns was monitored in an open field trial. Thermotherapy significantly decreased fungal diversity, while storage at 3 °C increased the isolation frequency of several fungi, mainly Penicillium spp. The most frequently isolated fungi did not show a negative impact on acorn germination after short-term storage. The study confirmed the efficiency of thermotherapy in the eradication of a part of acorn internal mycobiota, but also its effect on the proliferation of fast-colonizing fungi during storage. However, the latter showed to be more stimulated by storage conditions, specifically by storage at 3 °C.
Forest Surface Changes and Cultural Values: The Forests of Tuscany (Italy) in the Last Century
Authors: Piras Francesco , Venturi Martina , Corrieri Federica , Santoro Antonio , Agnoletti Mauro
Published: April 2021

Despite the definition of social and cultural values as the third pillar of Sustainable Forest Management (SFM) in 2003 and the guidelines for their implementation in SFM in 2007 issued by the Ministerial Conference on the Protection of Forest in Europe (MCPFE), the importance of cultural values is not sufficiently transferred into forest planning and conservation. Tuscany is widely known for the quality of its cultural landscape, however, the abandonment of agro-pastoral surfaces as a consequence of rural areas depopulation, has led to widespread reforestation and to the abandonment of forest management. In addition, due to the interruption of a regular forest management and to the fact that most of the population lives in cities, forests are no more perceived as part of the cultural heritage, but mainly as a natural landscape. Due to this trend traditional forest management techniques, such as coppicing, have also been considered as a factor of degradation and not even a historical management form. The aim of the study is therefore to analyze forest surface changes in Tuscany in the last century to assess the importance of cultural values. Results highlighted that already in 1881 most of forests were regularly managed and that in 1936 more than 76% of broadleaved forests were managed as coppice. Between 1936 and 2016 forests increased their surface from 876,518 to 1,161,383 hectares due to the abandonment of the countryside, and 30% of the forests currently included in protected areas are the result of secondary successions. The findings of this study suggest the revision of national forest policies and, more in general, the adaptation of forest strategies to local conditions.
Four Types of TiO2 Reduced the Growth of Selected Lactic Acid Bacteria Strains
Authors: Baranowska-Wójcik Ewa , Gustaw Klaudia , Szwajgier Dominik , Oleszczuk Patryk , Pawlikowska-Pawlęga Bożena , Pawelec Jarosław , Kapral-Piotrowska Justyna
Published: April 2021

Food-grade titanium dioxide (TiO2) containing a nanoparticle fraction (TiO2 NPs -nanoparticles) is widely used as a food additive (E171 in the EU). In recent years, it has increasingly been raising controversies as to the presence or absence of its harmful effects on the gastrointestinal microbiota. The complexity and variability of microbiota species present in the human gastrointestinal tract impede the assessment of the impact of food additives on this ecosystem. As unicellular organisms, bacteria are a very convenient research model for investigation of the toxicity of nanoparticles. We examined the effect of TiO2 (three types of food-grade E171 and one TiO2 NPs, 21 nm) on the growth of 17 strains of lactic acid bacteria colonizing the human digestive tract. Each bacterial strain was treated with TiO2 at four concentrations (60, 150, 300, and 600 mg/L TiO2). The differences in the growth of the individual strains were caused by the type and concentration of TiO2. It was shown that the growth of a majority of the analyzed strains was decreased by the application of E171 and TiO2 NPs already at the concentration of 150 and 300 mg/L. At the highest dose (600 mg/L) of the nanoparticles, the reactions of the bacteria to the different TiO2 types used in the experiment varied.
Bread Fortified with Cooked Purple Potato Flour and Citrus Albedo: An Evaluation of Its Compositional and Sensorial Properties
Authors: Taglieri Isabella , Sanmartin Chiara , Venturi Francesca , Macaluso Monica , Bianchi Alessandro , Sgherri Cristina , Quartacci Mike Frank , De Leo Marinella , Pistelli Luisa , Palla Fabrizio , Flamini Guido , Zinnai Angela
Published: April 2021

This research aimed to explore the feasibility of fortifying bread with cooked Vitelotte potato powder and Citrus albedo, comparing the use of baker’s yeast or sourdough as leavening agents. Breads obtained were thus subjected to physico-chemical and sensory characterizations. The replacement of part of the wheat flour with purple potato and albedo determined a significant enhancement of the phenolic profile and antioxidant status of fortified breads, as well as a longer shelf life. Thanks to its acidity and antimicrobial activity, sourdough improved the levels of health-promoting compounds and stability. Both the fortification and the leavening agent deeply affected the organoleptic, expression, and the aroma profile, of the fortified bread. Interestingly, albedo addition, despite its effectiveness in boosting the phenolic profile, determined a higher perception of aftertaste and bitterness, irrespective of the leavening agent. Based on these results, the use of purple potatoes and Citrus albedo, if properly formulated, could represent a valuable strategy for the development of high-quality products, with longer shelf-life.
Mitochondrial Processes during Early Development of Dictyostelium discoideum: From Bioenergetic to Proteomic Studies
Authors: Mazur Monika , Wojciechowska Daria , Sitkiewicz Ewa , Malinowska Agata , Świderska Bianka , Kmita Hanna , Wojtkowska Małgorzata
Published: April 2021

The slime mold Dictyostelium discoideum’s life cycle includes different unicellular and multicellular stages that provide a convenient model for research concerning intracellular and intercellular mechanisms influencing mitochondria’s structure and function. We aim to determine the differences between the mitochondria isolated from the slime mold regarding its early developmental stages induced by starvation, namely the unicellular (U), aggregation (A) and streams (S) stages, at the bioenergetic and proteome levels. We measured the oxygen consumption of intact cells using the Clarke electrode and observed a distinct decrease in mitochondrial coupling capacity for stage S cells and a decrease in mitochondrial coupling efficiency for stage A and S cells. We also found changes in spare respiratory capacity. We performed a wide comparative proteomic study. During the transition from the unicellular stage to the multicellular stage, important proteomic differences occurred in stages A and S relating to the proteins of the main mitochondrial functional groups, showing characteristic tendencies that could be associated with their ongoing adaptation to starvation following cell reprogramming during the switch to gluconeogenesis. We suggest that the main mitochondrial processes are downregulated during the early developmental stages, although this needs to be verified by extending analogous studies to the next slime mold life cycle stages.
Deletion of the Imprinted Phlda2 Gene Increases Placental Passive Permeability in the Mouse
Authors: Angiolini Emily , Sandovici Ionel , Coan Philip M. , Burton Graham J. , Sibley Colin P. , Fowden Abigail L. , Constância Miguel
Published: April 2021

Genomic imprinting, an epigenetic phenomenon that causes the expression of a small set of genes in a parent-of-origin-specific manner, is thought to have co-evolved with placentation. Many imprinted genes are expressed in the placenta, where they play diverse roles related to development and nutrient supply function. However, only a small number of imprinted genes have been functionally tested for a role in nutrient transfer capacity in relation to the structural characteristics of the exchange labyrinthine zone. Here, we examine the transfer capacity in a mouse model deficient for the maternally expressed Phlda2 gene, which results in placental overgrowth and a transient reduction in fetal growth. Using stereology, we show that the morphology of the labyrinthine zone in Phlda2−/+ mutants is normal at E16 and E19. In vivo placental transfer of radiolabeled solutes 14C-methyl-D-glucose and 14C-MeAIB remains unaffected at both gestational time points. However, placental passive permeability, as measured using two inert hydrophilic solutes (14C-mannitol; 14C-inulin), is significantly higher in mutants. Importantly, this increase in passive permeability is associated with fetal catch-up growth. Our findings uncover a key role played by the imprinted Phlda2 gene in modifying placental passive permeability that may be important for determining fetal growth.
Sleep Quality Is Associated with Vitamin B12 Status in Female Arab Students
Authors: Al-Musharaf Sara , Alabdulaaly Alanoud , Bin Mujalli Hanadi , Alshehri Hatoun , Alajaji Hind , Bogis Rania , Alnafisah Ruyuf , Alfehaid Shaden , Alhodaib Hala , Murphy Alice , Hussain Syed Danish , Sabico Shaun , McTernan Philip , Al-Daghri Nasser
Published: April 2021

Studies have explored how vitamin B12 status affects sleep among elders and children, but this remains to be investigated among young adults. We used the Pittsburgh Sleep Quality Index (PSQI) to assess the association between serum vitamin B12 and sleep among female college students in Saudi Arabia. In this cross-sectional study, we enrolled 355 participants (age (years), 20.7 ± 1.5; body mass index, 23.6 kg/m2 ± 5.2) at King Saud University, Riyadh, Saudi Arabia. Fasting blood samples were analyzed regarding the serum vitamin B12 and blood lipids. Anthropometric, socio-demographic, clinical history, stress, physical activity, and dietary data were collected. We assessed the sleep statuses of the participants using the PSQI. Around 72% of the participants were “poor” sleepers (PSQI > 5). Subgroup analysis within the tertiles showed that participants with higher vitamin B12 in the second and third tertiles reported better scores for sleep quality (B ± SE = −12.7 ± 5.6, p = 0.03; B ± SE = −32.7 ± 16.4, p = 0.05, respectively) and also reported a lower use of sleep medication (B ± SE = −21.2 ± 9.9, p = 0.03, in the second tertile only), after adjusting for the waist–hip ratio and stress. However, sleep was not found to be directly associated with either serum vitamin B12 or dietary vitamin B12. In conclusion, the serum vitamin B12 results show that the participants with higher vitamin B12 in the second and third tertiles reported better scores on the sleep quality scale and a lower use of sleep medication. However, no such associations were observed with the overall PSQI. More studies with larger sample sizes are needed to establish a direct relationship between sleep and vitamin B12.
Using WHODAS 2.0 to Assess Functional Impairment in People with Depression: Should Employment Receive More Attention?
Authors: Chiang Yu-Chen , Liou Tsan-Hon , Lee Hsin-Chien , Escorpizo Reuben
Published: April 2021

Background: Major depressive disorder (MDD) is a highly prevalent mental disorder which causes public health burden and personal disabilities. In people with mental illness, unemployment is an index character of functional impairment. Methods: Using the Taiwan Databank of Persons with Disability (TDPD), we collected the WHO Disability Assessment Schedule 2.0 (WHODAS 2.0) scores for people with MDD-associated disability. We recorded and analyzed the scores of participants during a 3-year period to determine the impact of employment on the trajectory of functional change. Logistic regression was performed to analyze the association between employment and changes in WHODAS 2.0 scores. Results: In people with MDD-associated disability, unemployed individuals present a worse function initially compared to employed individuals. After a 3-year period, the employed group showed a significant functional improvement in the domains of cognition, mobility, and participation. In logistic regression, the odds of having functional improvement were twice as high for those who were employed compared with those who were not. Conclusions: Higher odds of having functional improvement were noted in participants who stay in employment. Programs and strategies to help people with MDD-associated disability resume work warrant more clinical attention and supportive policies from the government.
Analysis of the Regional Efficiency of European Funds in Spain from the Perspective of Renewable Energy Production: The Regional Dimension
Authors: Mugambi Paul , Blanco Miguel , Ogachi Daniel , Ferasso Marcos , Bares Lydia
Published: April 2021

During the 2010–2020 period, the European Union (EU) launched a growth strategy based on three fundamental pillars: smart growth, sustainable growth, and inclusive growth. Aiming to finance the projects related to these growth pillars, the EU used mainly the Rural Development Funds, the Structural Funds, those derived from the R&D Framework Program, the Trans-European Networks, and the European Investment Bank. This research aimed to determine whether the Spanish regions maintain homogeneous efficiency levels by using these resources to improve the levels of environmental quality related to renewable energies. A methodology that is frequently used by researchers in efficiency analyses was chosen, the Data Envelopment Analysis (DEA). The main findings revealed that the efficiency in the use of renewable energies is very uneven among the Spanish regions and these differences are maintained throughout the period analyzed. These results highlighted the need of changes regarding the proposed criteria for allocating European resources to finance the projects presented by each Spanish region.
Influence of ESGC Indicators on Financial Performance of Listed Pharmaceutical Companies
Authors: López-Toro Alberto A. , Sánchez-Teba Eva María , Benítez-Márquez María Dolores , Rodríguez-Fernández Mercedes
Published: April 2021

The pharmaceutical industry, concerned about the impact of its activity, has integrated responsible principles and practices with a view to improving its sustainable and financial performance. This study analyzes the relationship between environmental, social, governance, and controversy indicators and financial performance, measured through return on equity (ROA), return on assets (ROE), and Tobin’s Q, which are applied to the listed companies in the Nasdaq US Smart Pharmaceuticals Index. This index is composed of 30 international companies with a presence at the global level. All the data have been extracted from the Thomson Reuters database. The analysis was performed using structural equation modeling implemented with partial least squares. The results confirm the positive relationship between the construct composed of environmental, social, and governance (ESG) indicators and the aforementioned financial ratios. Additionally, a positive relationship of the controversy indicator with Tobin’s Q is supported. This suggests that the pharmaceutical multinationals focus their investments in sustainability on ESG and pay attention to controversies to boost the visibility of the company and thus increase its value. These conclusions confirm that investing in ESG is a profitable strategy. It is also relevant for managers as it increases the profits and the market value of multinational pharmaceutical companies.
Future Academic Expectations and Their Relationship with Motivation, Satisfaction of Psychological Needs, Responsibility, and School Social Climate: Gender and Educational Stage
Authors: Manzano-Sánchez David , Gómez-Mármol Alberto , Conte Marín Luis , Jiménez-Parra José Francisco , Valero-Valenzuela Alfonso
Published: April 2021

The purpose of this study was to show the relationship between future academic expectations and the concepts of motivation, basic psychological needs, school social climate, and responsibility. Additionally, possible differences in future expectations were analyzed according to gender and educational stage. A total of 984 students (M = 12.87; SD = 1.84) from elementary and secondary school participated in this study. A single questionnaire composed of different scales was administered to check the values of motivation (EME), psychological need satisfaction (PNSE), school social climate (CECSCE), responsibility (PSRQ), sociodemographic differences, and a question to find out future academic expectations. Results showed that the group with the highest future expectations (do a degree or upper vocational training) had statistical differences of p < 0.001 with respect to the group with the lowest future expectations (finish compulsory secondary studies or basic vocational training and start work) and middle expectations (do a high school or middle vocational training) with regard to autonomous motivation, satisfaction of psychological needs, school and teacher climate, and social and personal responsibility. The group with the lowest expectations had higher values with respect to the other two groups in terms of amotivation (p < 0.001). Moreover, women and elementary school children had greater future academic expectations (p < 0.001). In conclusion, the promotion of basic psychological needs satisfaction, autonomous motivation, personal and social responsibility, and school social climate are related to higher academic expectations, and the improvement of these variables becomes especially important for boys and secondary students who could have a higher chance of dropping out of school.
Associations between Google Search Trends for Symptoms and COVID-19 Confirmed and Death Cases in the United States
Authors: Abbas Mostafa , Morland Thomas B. , Hall Eric S. , EL-Manzalawy Yasser
Published: April 2021

We utilize functional data analysis techniques to investigate patterns of COVID-19 positivity and mortality in the US and their associations with Google search trends for COVID-19-related symptoms. Specifically, we represent state-level time series data for COVID-19 and Google search trends for symptoms as smoothed functional curves. Given these functional data, we explore the modes of variation in the data using functional principal component analysis (FPCA). We also apply functional clustering analysis to identify patterns of COVID-19 confirmed case and death trajectories across the US. Moreover, we quantify the associations between Google COVID-19 search trends for symptoms and COVID-19 confirmed case and death trajectories using dynamic correlation. Finally, we examine the dynamics of correlations for the top nine Google search trends of symptoms commonly associated with COVID-19 confirmed case and death trajectories. Our results reveal and characterize distinct patterns for COVID-19 spread and mortality across the US. The dynamics of these correlations suggest the feasibility of using Google queries to forecast COVID-19 cases and mortality for up to three weeks in advance. Our results and analysis framework set the stage for the development of predictive models for forecasting COVID-19 confirmed cases and deaths using historical data and Google search trends for nine symptoms associated with both outcomes.
Cultivation of Head and Neck Squamous Cell Carcinoma Cells with Wound Fluid Leads to Cisplatin Resistance via Epithelial-Mesenchymal Transition Induction
Authors: Meyer Till Jasper , Stöth Manuel , Moratin Helena , Ickrath Pascal , Herrmann Marietta , Kleinsasser Norbert , Hagen Rudolf , Hackenberg Stephan , Scherzad Agmal
Published: April 2021

Locoregional recurrence is a major reason for therapy failure after surgical resection of head and neck squamous cell carcinoma (HNSCC). The physiological process of postoperative wound healing could potentially support the proliferation of remaining tumor cells. The aim of this study was to evaluate the influence of wound fluid (WF) on the cell cycle distribution and a potential induction of epithelial-mesenchymal transition (EMT). To verify this hypothesis, we incubated FaDu and HLaC78 cells with postoperative WF from patients after neck dissection. Cell viability in dependence of WF concentration and cisplatin was measured by flow cytometry. Cell cycle analysis was performed by flow cytometry and EMT-marker expression by rtPCR. WF showed high concentrations of interleukin (IL)-6, IL-8, IL-10, CCL2, MCP-1, EGF, angiogenin, and leptin. The cultivation of tumor cells with WF resulted in a significant increase in cell proliferation without affecting the cell cycle. In addition, there was a significant enhancement of the mesenchymal markers Snail 2 and vimentin, while the expression of the epithelial marker E-cadherin was significantly decreased. After cisplatin treatment, tumor cells incubated with WF showed a significantly higher resistance compared with the control group. The effect of cisplatin-resistance was dependent on the WF concentration. In summary, proinflammatory cytokines are predominantly found in WF. Furthermore, the results suggest that EMT can be induced by WF, which could be a possible mechanism for cisplatin resistance.
Leptin Receptor Compound Heterozygosity in Humans and Animal Models
Authors: Berger Claudia , Klöting Nora
Published: April 2021

Leptin and its receptor are essential for regulating food intake, energy expenditure, glucose homeostasis and fertility. Mutations within leptin or the leptin receptor cause early-onset obesity and hyperphagia, as described in human and animal models. The effect of both heterozygous and homozygous variants is much more investigated than compound heterozygous ones. Recently, we discovered a spontaneous compound heterozygous mutation within the leptin receptor, resulting in a considerably more obese phenotype than described for the homozygous leptin receptor deficient mice. Accordingly, we focus on compound heterozygous mutations of the leptin receptor and their effects on health, as well as possible therapy options in human and animal models in this review.
Xanthohumol for Human Malignancies: Chemistry, Pharmacokinetics and Molecular Targets
Authors: Harish Vancha , Haque Effi , Śmiech Magdalena , Taniguchi Hiroaki , Jamieson Sarah , Tewari Devesh , Bishayee Anupam
Published: April 2021

Xanthohumol (XH) is an important prenylated flavonoid that is found within the inflorescence of Humulus lupulus L. (Hop plant). XH is an important ingredient in beer and is considered a significant bioactive agent due to its diverse medicinal applications, which include anti-inflammatory, antimicrobial, antioxidant, immunomodulatory, antiviral, antifungal, antigenotoxic, antiangiogenic, and antimalarial effects as well as strong anticancer activity towards various types of cancer cells. XH acts as a wide ranging chemopreventive and anticancer agent, and its isomer, 8-prenylnaringenin, is a phytoestrogen with strong estrogenic activity. The present review focuses on the bioactivity of XH on various types of cancers and its pharmacokinetics. In this paper, we first highlight, in brief, the history and use of hops and then the chemistry and structure–activity relationship of XH. Lastly, we focus on its prominent effects and mechanisms of action on various cancers and its possible use in cancer prevention and treatment. Considering the limited number of available reviews on this subject, our goal is to provide a complete and detailed understanding of the anticancer effects of XH against different cancers.
Anti-Inflammatory Role of Netrin-4 in Diabetic Retinopathy
Authors: Crespo-Garcia Sergio , Reichhart Nadine , Kociok Norbert , Skosyrski Sergej , Joussen Antonia M.
Published: April 2021

Diabetic retinopathy is characterized by dysfunction of the retinal vascular network, combined with a persistent low-grade inflammation that leads to vision-threatening complications. Netrin-4 (NTN4) is a laminin-related secreted protein and guidance cue molecule present in the vascular basal membrane and highly expressed in the retina. A number of studies inferred that the angiogenic abilities of NTN4 could contribute to stabilize vascular networks and modulate inflammation. Analyzing human specimens, we show that NTN4 and netrin receptors are upregulated in the diabetic retina. We further evaluated a knock-out model for NTN4 undergoing experimental diabetes induced by streptozotocin. We investigated retina function and immune cells in vivo and demonstrated that NTN4 provides a protective milieu against inflammation in the diabetic retina and prevents cytokine production.
Prognostic Implication of Non-Obstructive Coronary Lesions: A New Classification in Different Settings
Authors: Rodríguez-Capitán Jorge , Sánchez-Pérez Andrés , Ballesteros-Pradas Sara , Millán-Gómez Mercedes , Cardenal-Piris Rosa , Oneto-Fernández Manuel , Gutiérrez-Alonso Lola , Rivera-López Ricardo , Guisado-Rasco Agustín , Cano-García Macarena , Gutiérrez-Bedmar Mario , Jiménez-Navarro Manuel
Published: April 2021

The clinical significance of non-obstructive coronary artery disease is the subject of debate. Our objective was to evaluate the long-term cardiovascular prognosis associated with non-obstructive coronary artery disease in patients undergoing coronary angiography, and to conduct a stratification by sex, diabetes, and clinical indication. We designed a multi-centre retrospective longitudinal observational study of 3265 patients that were classified into three groups: normal coronary arteries (lesion <20%, 1426 patients), non-obstructive coronary artery disease (20–50%, 643 patients), and obstructive coronary artery disease (>70%, 1196 patients). During a mean follow-up of 43 months, we evaluated a combined cardiovascular event: acute myocardial infarction, stroke, hospitalization for heart failure, or cardiovascular death. Multivariable-adjusted Cox proportional hazard models showed a worse prognosis in patients with non-obstructive coronary artery disease, in comparison with patients of normal coronary arteries group, in the total population (hazard ratio 1.72, 95% confidence interval 1.23–2.39; p for trend <0.001), in non-diabetics (hazard ratio 2.12, 95% confidence interval: 1.40–3.22), in women (hazard ratio 1.75, 95% confidence interval 1.10–2.77), and after acute coronary syndrome (hazard ratio 2.07, 95% confidence interval 1.25–3.44). In conclusion, non-obstructive coronary artery disease is associated with an impaired long-term cardiovascular prognosis. This association held for non-diabetics, women, and after acute coronary syndrome.
How Good Is the STW Sensor? An Account from a Larger Shipping Company
Authors: Ikonomakis Angelos , Nielsen Ulrik Dam , Holst Klaus Kähler , Dietz Jesper , Galeazzi Roberto
Published: April 2021

This paper examines the statistical properties and the quality of the speed through water (STW) measurement based on data extracted from almost 200 container ships of Maersk Line’s fleet for 3 years of operation. The analysis uses high-frequency sensor data along with additional data sources derived from external providers. The interest of the study has its background in the accuracy of STW measurement as the most important parameter in the assessment of a ship’s performance analysis. The paper contains a thorough analysis of the measurements assumed to be related with the STW error, along with a descriptive decomposition of the main variables by sea region including sea state, vessel class, vessel IMO number and manufacturer of the speed-log installed in each ship. The paper suggests a semi-empirical method using a threshold to identify potential error in a ship’s STW measurement. The study revealed that the sea region is the most influential factor for the STW accuracy and that 26% of the ships of the dataset’s fleet warrant further investigation.
Functional Analysis of an Essential GSP1/Ran Ortholog Gene, CpRan1, from the Chestnut Blight Fungus Cryphonectria parasitica Using a Heterokaryon
Authors: Ko Yo-Han , Chun Jeesun , Kim Dae-Hyuk
Published: April 2021

Functional analysis of a GSP1/Ran ortholog, CpRan1, from Cryphonectria parasitica was conducted. Genotype analysis revealed that the putative CpRan1-null mutant was a heterokaryotic transformant harboring two different types of nuclei, one with the wild-type CpRan1 allele and the other with the CpRan1-null mutant allele. The mycelial growth and colony morphology of the heterokaryotic transformant was normal. Microscopic analysis of the resulting conidia (aseptate and monokaryotic asexual spores) demonstrated that although normal germinating spores were observed from conidia harboring a nucleus with the wild-type CpRan1 allele, a number of residual conidia that did not germinate existed. Complementation analysis using protoplasts from the heterokaryon with the wild-type CpRan1 allele confirmed that the CpRan1 gene is essential to C. parasitica. Complementation analysis using the various CpRan1 chimera constructs allowed us to perform a functional analysis of essential amino acids of the CpRan1. Among the four suggested essential amino acids, Lys-97 for ubiquitination was determined to not be an essential residue. Moreover, the CpRan1-null mutant allele was successfully complemented with mouse Ran gene, which suggested that the biological function of Ran gene is evolutionary conserved and that our heterokaryon rescue can be applied for the functional analysis of heterologous genes.
The Development of a Personalized Symptom Management Mobile Health Application for Persons Living with HIV in China
Authors: Han Shuyu , Pei Yaolin , Wang Lina , Hu Yan , Qi Xiang , Zhao Rui , Zhang Lin , Sun Wenxiu , Zhu Zheng , Wu Bei
Published: April 2021

Persons living with HIV (PLWH) continuously experience symptom burdens. Their symptom prevalence and severity are also quite different. Mobile health (mHealth) applications (apps) offer exceptional opportunities for using personalized interventions when and where PLWH are needed. This study aimed to demonstrate the development process of the symptom management (SM) app and the structure and content of it. Our research team systematically searched for evidence-based resources and summarized up-to-date evidence for symptom management and health education. Our multidisciplinary research team that included physicians, nurses, software engineers, and nursing professors, evaluated the structure and content of the drafted app. Both quantitative data and qualitative results were collected at a group discussion meeting. Quantitative data were scores of sufficient evidence, situational suitability, practicability, cost-effectiveness, and understandability (ranged from one to four) for 119 items of the app contents, including the health tracking module, the self-assessment module, coping strategies for 18 symptoms (80 items), medication management, complementary therapy, diet management, exercise, relaxation techniques, and the obtaining support module. The SM app was comprised of eight modules and provided several personalized symptom management functions, including assessing symptoms and receiving different symptom management strategies, tracking health indicators, and communicating with medical staff. The SM app was a promising and flexible tool for HIV symptom management. It provided PLWH with personalized symptom management strategies and facilitated the case management for medical staff. Future studies are needed to further test the app’s usability among PLWH users and its effects on symptom management.