bluuebunny/crossref_metadata_2025 huggingface dataset:
A Feature Tensor-Based Epileptic Detection Model Based on Improved Edge Removal Approach for Directed Brain Networks
Authors: Song Chuancheng , Huo Youliang , Ma Junkai , Ding Weiwei , Wang Liye , Dai Jiafei , Huang Liya
Published: December 2020

Electroencephalograph (EEG) plays a significant role in the diagnostics process of epilepsy, but the detection rate is unsatisfactory when the length of interictal EEG signals is relatively short. Although the deliberate attacking theories for undirected brain network based on node removal method can extract potential network features, the node removal method fails to sufficiently consider the directionality of brain electrical activities. To solve the problems above, this study proposes a feature tensor-based epileptic detection method of directed brain networks. First, a directed functional brain network is constructed by calculating the transfer entropy of EEG signals between different electrodes. Second, the edge removal method is used to imitate the disruptions of brain connectivity, which may be related to the disorder of brain diseases, to obtain a sequence of residual networks. After that, topological features of these residual networks are extracted based on graph theory for constructing a five-way feature tensor. To exploit the inherent interactions among multiple modes of the feature tensor, this study uses the Tucker decomposition method to get a core tensor which is finally reshaped into a vector and input into the support vectors machine (SVM) classifier. Experiment results suggest that the proposed method has better epileptic screening performance for short-term interictal EEG data.
Prevalence of Depression and Anxiety Symptoms of High School Students in Shandong Province During the COVID-19 Epidemic
Authors: Zhang Zeng , Zhai Ailing , Yang Mingchuan , Zhang Junqing , Zhou Haotian , Yang Chuanming , Duan Shanshan , Zhou Cong
Published: December 2020

Background: The coronavirus disease 2019 (covid-19) has brought physical risks as well as psychological challenges to the whole world. High school students are a special group suffering from both the academic pressure and the threat of the epidemic. The present study aims to conduct an online survey to investigate the psychological status of high school students in Shandong Province.

Methods: Using a web-based cross-sectional survey, data was collected from 1,018 voluntary high school students assessed with demographic information, the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 (GAD-7) and a self-designed online-study effect survey. Correlation analysis was performed to explore the relationships between depression symptoms, anxiety symptoms, and study effect.

Result: The prevalence of depressive symptoms, anxiety symptoms, and a combination of depressive and anxiety symptoms was 52.4, 31.4, and 26.8%, respectively, among high school students in Shandong Province during the COVID-19 epidemic. And from moderate to severe severity level, the rates of depressive symptoms and anxious symptoms were 17.6 and 4.6%. Female students exhibited a higher rate and severity of mental symptoms than male, and grade one senior high school students got a higher rate and severity of mental symptoms than the other two grades. Nearly half of the students were not satisfied with their online-study effect. The PHQ-9 score had a strong positive correlation with the GAD-7 score. Both the PHQ-9 score the GAD-7 score had a negative correlation with the study-effect survey score.

Conclusion: Quite a number of high school students suffered from depression and anxiety symptoms during the COVID-19 epidemic. Sufficient attentions should be paid, and necessary supports should be provided, to protect the mental health of this special group.
Analysis on the Development of Digital Economy in Guangdong Province Based on Improved Entropy Method and Multivariate Statistical Analysis
Authors: Deng Xue , Liu Yuying , Xiong Ye
Published: December 2020

The lack of adequate indicators in the research of digital economy may lead to the shortage of data support on decision making for governments. To solve this problem, first we establish a digital economy indicator evaluation system by dividing the digital economy into four types: “basic type”, “technology type”, “integration type” and “service type” and select 5 indicators for each type. On this basis, the weight of each indicator is calculated to find the deficiencies in the development of some digital economic fields by the improved entropy method. By drawing on the empowerment idea of Analytic Hierarchy Process, the improved entropy method firstly compares the difference coefficient of indicators in pairs and maps the comparison results to the scales 1–9. Then, the judgment matrix is constructed based on the information entropy, which can solve as much as possible the problem that the difference among the weight of each indicator is too large in traditional entropy method. The results indicate that: the development of digital economy in Guangdong Province was relatively balanced from 2015 to 2018 and will be better in the future while the development of rural e-commerce in Guangdong Province is relatively backward, and there is an obvious digital gap between urban and rural areas. Next we extract two new variables respectively to replace the 20 indicators we select through principal component analysis and factor analysis methods in multivariate statistical analysis, which can retain the original information to the greatest extent and provide convenience for further research in the future. Finally, we and provide constructive comments of digital economy in Guangdong Province from 2015 to 2018.
Influence of Substrate Type and Dose of Implanted Ions on the Electrical Parameters of Silicon in Terms of Improving the Efficiency of Photovoltaic Cells
Authors: Węgierek Paweł , Pastuszak Justyna , Dziadosz Kamil , Turek Marcin
Published: December 2020

The main goal of this work was to conduct a comparative analysis of the electrical properties of the silicon implanted with neon ions, depending on the dose of ions and the type of substrate doping, for the possibility of generating additional energy levels by ion implantation in terms of improving the efficiency of photovoltaic cells made on its basis. The article presents the results of research on the capacitance and conductance of silicon samples doped with boron and phosphorus, the structure of which was modified in the implantation process with Ne+ ions with energy E = 100 keV and different doses. The analysis of changes in electrical properties recorded at the annealing temperature of the samples Ta = 298 K, 473 K, 598 K, 673 K, and 873 K, concerned the influence of the test temperature in the range from 203 K to 373 K, as well as the frequency f from 100 Hz to 10 MHz, and voltage U from 0.25 V to 2 V. It was possible to detect intermediate bands in the tested samples and determine their position in the band gap by estimating the activation energy value. By means of implantation, it is possible to modify the width of the silicon energy gap, the value of which directly affects the efficiency of the photovoltaic cell made on its basis. By introducing appropriate defects into the silicon crystal lattice, contributing to a change in the value of the energy gap Eg, it is possible to increase the efficiency of the solar cell. On the basis of the obtained results, it can be seen that the highest activation energies are achieved for samples doped with phosphorus.
Using the Analysis of the Gases Dissolved in Oil in Diagnosis of Transformer Bushings with Paper-Oil Insulation—A Case Study
Authors: Piotrowski Tomasz , Rozga Pawel , Kozak Ryszard , Szymanski Zbigniew
Published: December 2020

The article describes a case study when the voltage collapse during lightning impulse tests of new power transformers was noticed and when the repeated tests finished with a positive result. The step-by-step process of reaching the conclusion on the basis of dissolved gas analysis (DGA) as a key method of the investigations was presented. The considerations on the possible source of the analysis showed that the Duval triangle method, used in the analysis of the concentration of gases dissolved in oil samples taken from bushings, more reliably and unambiguously than the ratio method recommended in the IEC 60599 Standard, indicated a phenomenon which was identified in the insulation structure of bushings analyzed. Additionally, the results from DGA were found to be consistent with an internal inspection of bushings, which showed a visible trace of discharge on the inside part of the epoxy housing, as a result of the lightning induced breakdown.
Nonlinear Digital Simulation Models of Switched Reluctance Motor Drive
Authors: Wang Xing , Palka Ryszard , Wardach Marcin
Published: December 2020

The paper deals with nonlinear simulation models of a drive consisting of the four-phase 8/6 doubly salient switched reluctance motor (SRM), the four-phase dissymmetric bridge power converter and the closed-cycle rotor speed control strategy carried out by the pulse width modulation (PWM) with variable angle and combined control scheme with the PI algorithm. All presented considerations are based on a MATLAB-SIMULINK platform. The nonlinear mathematical model of the analyzed SRM drive was obtained as a combination of the two dimensional (2D) finite element model (FEM) of the motor and the nonlinear model of the electrical network of the power supply circuit. The main model and its seven sub-modules, such as the controller module, one phase simulation module, rotor position angle transformation module, power system module, phase current operation module, “subsystem” module, and electromagnetic torque of one phase operation module, are described. MATLAB functions store the magnetization curves data of the motor obtained by the 2D FEM electromagnetic field calculations, as well as the data of magnetic co-energy curves of the motor calculated from the magnetization curves. The 2D specimen insert method is adopted in MATLAB functions for operating the flux linkage and the magnetic co-energy at the given phase current and rotor position. The phase current waveforms obtained during simulations match with the tested experimentally phases current waveforms at the same rotor speed and the same load basically. The simulated rotor speed curves also agree with the experimental rotor speed curves. This means that the method of suggested nonlinear simulation models of the analyzed SRM drive is correct, and the model is accurate.
Global Horizontal Irradiance Modeling for All Sky Conditions Using an Image-Pixel Approach
Authors: de Sá Campos Manoel Henriques , Tiba Chigueru
Published: December 2020

Ground images with a sky camera have become common to evaluate cloud coverage, aerosols, and energy collection. In parallel, the growth of solar energy has led to an impulse to evaluate and forecast the solar potential in a site before investments, which has increased the importance of solar power measurements. Facing that scenario, this work presents a novel sky camera model that allows to measure the global horizontal irradiance (GHI). Initially, images from a fisheye camera were stored and a pixel-based approach model was created for cloud segmentation. A total of 813 k vectors of features were used as input to the support vector machine for classification (SVC), which yielded a success rate of about 98.6% in accuracy. The Sun’s position was also segmented and an artificial neural network (ANN) regression model for GHI with 17 input features was created based on segmentation of the Sun, clouds, and sky. The training/validation stage of the ANN used 89,964 samples and the test stage reached about 97.4% in Pearson’s correlation. The RMSE was 72.3 W/m2 for GHI and the normalized RMSE, nRMSE, revealed 12.9% for GHI. That nRMSE value was comparable to or lower than other studies, despite the high fluctuations in the observed GHI.
Cell-Set Modelling for a Microtab Implementation on a DU91W(2)250 Airfoil
Authors: Ballesteros-Coll Alejandro , Fernandez-Gamiz Unai , Aramendia Iñigo , Zulueta Ekaitz , Ramos-Hernanz José Antonio
Published: December 2020

Microtabs (MTs) are a regularly used flow control device in terms of wind turbine optimization. The present study introduces the application of the novel cell-set model for an MT implementation on a DU91W(2)250 airfoil. The cell-set model is based on the reusability of a mesh to add new geometries on the domain; the matching geometry is located where the user requires, and a set of cells is constructed around the mentioned geometry. Subsequently, wall boundaries are assigned to the generated region. Computational simulations were carried out for fully mesh and cell-set models: MT lengths were set at 1.0%, 1.5% and 2.0% of the airfoil chord length (c) and the MTs were placed at 93% and 95% of c from the leading edge of the airfoil. Resulting data showed that the MT behavior was similar for both models with regard to aerodynamic performance curve representations. A global relative error of 3.784% was obtained for the cell-set model and a maximum relative error of 7.332% was determined. Qualitatively, both models generated significantly similar flow stream velocity wakes on the trailing edge area of the airfoil.
Impact of the Minimum Head on Low-Head Hydropower Plants Energy Production and Profitability
Authors: Ceran Bartosz , Jurasz Jakub , Wróblewski Robert , Guderski Adam , Złotecka Daria , Kaźmierczak Łukasz
Published: December 2020

In Poland, existing barrages are characterized by relatively high flow and low head, which is challenging for the effective utilization of theoretical watercourse power. The paper presents the impact of the minimum head of the hydro sets on the annual electricity production of small hydropower plants at low-head locations for two types of water turbines: Archimedes and Kaplan turbines. A developed mathematical model was used to simulate energy yield from Archimedes and Kaplan turbines for a given value of the minimum technical head, depending on the number of installed hydro sets. For economic analysis purposes, the levelized cost of electricity (LCOE) and net present value (NPV) indicators were calculated. The conducted research allowed for comparing Archimedes and Kaplan’s turbine operating conditions and how the minimum head parameter influences their electricity production and utilization time. As concluded in the results, the influence of minimum head in energy production is more distinct for the Archimedes screw technology than for the Kaplan turbine. The research shows that the decrease in energy production associated with the hydro unit’s minimum head parameter is from 0% to 30% for Kaplan, and it is 6% to 52% for Archimedes turbines.
A Tool for Evaluating the Performance of SiC-Based Bidirectional Battery Chargers for Automotive Applications
Authors: Aiello Giuseppe , Cacciato Mario , Gennaro Francesco , Rizzo Santi Agatino , Scarcella Giuseppe , Scelba Giacomo
Published: December 2020

In this paper, a procedure to simulate an electronic power converter for control design and optimization purposes is proposed. For the addressed application, the converter uses SiC-MOSFET technology in bidirectional battery chargers composed of two power stages. The first stage consists of a single-phase AC/DC power factor correction synchronous rectifier. The following stage is a DC/DC dual active bridge. The converter has been modulated using a phase-shift technique which is able to manage bidirectional power flows. The development of a model-based simulation approach is essential to simplify the different design phases. Moreover, it is also important for the final validation of the control algorithm. A suitable tool consisting of a system-level simulation environment has been adopted. The tool is based on a block diagram design method accomplished using the Simulink toolbox in MATLAB™.
Analysis on Displacement Angle of Phase-Shifted Carrier PWM for Modular Multilevel Converter
Authors: Cheng Qian , Wang Chenchen , Wang Jian
Published: December 2020

This paper provides theoretical and experimental discussions on the characteristics of the modular multilevel converter (MMC) when phase-shifted carrier sinusoidal pulse-width modulation (PSC-SPWM) is applied. Harmonic-cancellation characteristics of output voltage and circulating current are analyzed on the basis of a general implementation of PSC-SPWM with two freedom displacement angles. Five available PSC-SPWM schemes with different carrier displacement angles were obtained, and a detailed performance comparison about output voltage and circulating current harmonic characteristics is presented. On the basis of the equivalent circuit with ideal transformer representation of the SMs, capacitor voltages affected by PSC-SPWM schemes are also briefly analyzed. The proposed PSC-SPWM schemes can unify two different cases of odd and even SM situations for output voltage and circulating current harmonic minimization, respectively. Lastly, the optimal schemes for practical MMC application were verified by simulation and experiments on an MMC prototype.
Essential Medicines in Universal Health Coverage: A Scoping Review of Public Health Law Interventions and How They Are Measured in Five Middle-Income Countries
Authors: Perehudoff Katrina , Demchenko Ivan , Alexandrov Nikita V. , Brutsaert David , Ackon Angela , Durán Carlos E. , El-Dahiyat Faris , Hafidz Firdaus , Haque Rezwan , Hussain Rabia , Salenga Roderick , Suleman Fatima , Babar Zaheer-Ud-Din
Published: December 2020

Very few studies exist of legal interventions (national laws) for essential medicines as part of universal health coverage in middle-income countries, or how the effect of these laws is measured. This study aims to critically assess whether laws related to universal health coverage use five objectives of public health law to promote medicines affordability and financing, and to understand how access to medicines achieved through these laws is measured. This comparative case study of five middle-income countries (Ecuador, Ghana, Philippines, South Africa, Ukraine) uses a public health law framework to guide the content analysis of national laws and the scoping review of empirical evidence for measuring access to medicines. Sixty laws were included. All countries write into national law: (a) health equity objectives, (b) remedies for users/patients and sanctions for some stakeholders, (c) economic policies and regulatory objectives for financing (except South Africa), pricing, and benefits selection (except South Africa), (d) information dissemination objectives (ex. for medicines prices (except Ghana)), and (e) public health infrastructure. The 17 studies included in the scoping review evaluate laws with economic policy and regulatory objectives (n = 14 articles), health equity (n = 10), information dissemination (n = 3), infrastructure (n = 2), and sanctions (n = 1) (not mutually exclusive). Cross-sectional descriptive designs (n = 8 articles) and time series analyses (n = 5) were the most frequent designs. Change in patients’ spending on medicines was the most frequent outcome measure (n = 5). Although legal interventions for pharmaceuticals in middle-income countries commonly use all objectives of public health law, the intended and unintended effects of economic policies and regulation are most frequently investigated.
Exertion Perception When Performing Cutting Tasks in Poultry Slaughterhouses: Risk Assessment of Developing Musculoskeletal Disorders
Authors: Tirloni Adriana Seára , dos Reis Diogo Cunha , Tirloni Salvador Francisco , Moro Antônio Renato Pereira
Published: December 2020

Brazil is the leader in poultry meat exports, in which most products are in the form of cuts. This study analyzed the exertion perception of poultry slaughterhouses workers when performing cutting tasks, as well as the influence of knife sharpness on the risk of developing musculoskeletal disorders by Occupational Repetitive Action (OCRA) method. Participants (n = 101) from three slaughterhouses were asked to rate their perceived exertion on the Borg scale during the cutting task when the knife was well and poorly sharpened. The OCRA results showed that the score for cutting with a dull knife was greater (43.57 ± 13.51) than with a sharp knife (23.79 ± 3.10) (p < 0.001). Consequently, there was a significant increase in the risk level of acquiring upper-limb work-related musculoskeletal disorders (UL-WMSD) by using a “poorly sharpened” knife (29%; p < 0.001; Borg scale 2–8). Thus, maintaining well-sharpened knives for optimal performance of the cutting task (fewer technical actions) is suggested, as well as including knife sharpening in the standard operating procedure to reduce musculoskeletal disorders.
Analysis of the Circular Economic Production Models and Their Approach in Agriculture and Agricultural Waste Biomass Management
Authors: Duque-Acevedo Mónica , Belmonte-Ureña Luis Jesús , Yakovleva Natalia , Camacho-Ferre Francisco
Published: December 2020

As of now, circular economic production models of the circular economy (CEPMs), which include circular economy, bioeconomy, and circular bioeconomy, are among the main tools characterizing development policies in different countries. During the last five years, policies and strategies regarding CEPMs have promoted and contributed to the development of research on this topic. The evolution and most relevant aspects of the three CEPMs previously mentioned have been analyzed from a sample of 2190 scientific publications obtained from the Scopus database. Bibliometric analysis has been used to evaluate the approach of these models in agriculture and to introduce the ways in which they address the management of agricultural waste biomass (AWB). Results show that the circular economy is the most studied and prioritized model in China and most European countries, with the UK leading the way. Germany leads in topics related to the bioeconomy. The management policies and strategies of the circular bioeconomy are key to promoting research focused on AWB valorization since bioenergy and/or biofuel production continue to be a priority.
Ritualistic Institution and Livelihood Fragility of Female Migrant Workers in Urban China
Authors: Wang Chao , Tang Jiayi
Published: December 2020

China’s rapid urbanization can be attributed, in part, to the contribution of female migrant workers. However, they are a socially vulnerable group. In order to explore the vulnerability of female migrant workers and its reasons, questionnaires and in-depth interviews were conducted with female migrant workers in Guangdong and Hubei provinces, China, and 992 questionnaires and 147 interview data were finally collected as the research object. The descriptive statistical analysis was conducted with the quantitative data to reveal the livelihood vulnerability of female migrant workers and its reasons, and qualitative data were used to corroborate and consolidate the argument. “Ritualistic institution” is the key to understanding the livelihood fragility of female migrant workers. The policy on migrant workers has weakened the concept of family, making it difficult for families, which are on the fringes of the national policy vision, to benefit from the system. Therefore, the livelihood costs of female migrant workers have increased. Traditional gender norms also make it difficult for migrant women to enjoy the limited benefits and resources of the policy. This weakens the authoritative role of the policy in solving the problem of livelihood vulnerability for migrant workers, particularly women. This shows that China’s policy on migrant workers is somewhat symbolic. Through “family separation” and “ritualistic institution”, it can be seen that China’s urbanization is a modern development activity that carries urban bias and lacks humanistic care value. This is bound to result in the neglect of human development, gender differences, and family, making it difficult for rural migrant women to survive. This in-depth study seeks to find solutions to the problems prevalent under the cover of contemporary Chinese modernity.
Survey on Recommended Health Care for Adult Patients with Myelodysplastic Syndromes Identifies Areas for Improvement
Authors: Chanias Ioannis , Wilk C. , Benz Rudolf , Daskalakis Michael , Stüssi Georg , Schmidt Adrian , Bacher Ulrike , Bonadies Nicolas ,   on behalf of the Swiss MDS Study Group
Published: December 2020

The impact on health care of patients with myelodysplastic syndromes (MDS) is continuously rising. To investigate the perception of hemato-oncologists concerning the recommended MDS patient care in Switzerland, we conducted a web-based survey on diagnosis, risk-stratification and treatment. 43/309 physicians (13.9%) replied to 135 questions that were based on current guidelines between 3/2017 and 2/2018. Only questions with feedback-rates >50% were further analysed and ratios >90% defined “high agreement”, 70–90% “agreement”, 30–70% “insufficient agreement” and <30% “disagreement”. For diagnosis, we found insufficient agreement on using flow-cytometry, classifying MDS precursor conditions, performing treatment response assessment after hypomethylating agents (HMA) and evaluating patients with suspected germ-line predisposition. For risk-stratification, we identified agreement on using IPSS-R but insufficient agreement for IPSS and patient-based assessments. For treatment, we observed disagreement on performing primary infectious prophylaxis in neutropenia but agreement on using only darbepoetin alfa in anaemic, lower-risk MDS patients. For thrombopoietin receptor agonists, insufficient agreement was found for the indication, preferred agent and triggering platelet count. Insufficient agreement was also found for immunosuppressive treatment in hypoplastic MDS and HMA dose adjustments. In conclusion, we identified areas for improvement in MDS patient care, in need of further clinical trials, information, and guiding documents.
Is Environmental and Occupational Particulate Air Pollution Exposure Related to Type-2 Diabetes and Dementia? A Cross-Sectional Analysis of the UK Biobank
Authors: Dimakakou Eirini , Johnston Helinor J. , Streftaris George , Cherrie John W.
Published: December 2020

Human exposure to particulate air pollution (e.g., PM2.5) can lead to adverse health effects, with compelling evidence that it can increase morbidity and mortality from respiratory and cardiovascular disease. More recently, there has also been evidence that long-term environmental exposure to particulate air pollution is associated with type-2 diabetes mellitus (T2DM) and dementia. There are many occupations that may expose workers to airborne particles and that some exposures in the workplace are very similar to environmental particulate pollution. We conducted a cross-sectional analysis of the UK Biobank cohort to verify the association between environmental particulate air pollution (PM2.5) exposure and T2DM and dementia, and to investigate if occupational exposure to particulates that are similar to those found in environmental air pollution could increase the odds of developing these diseases. The UK Biobank dataset comprises of over 500,000 participants from all over the UK. Environmental exposure variables were used from the UK Biobank. To estimate occupational exposure both the UK Biobank’s data and information from a job exposure matrix, specifically developed for UK Biobank (Airborne Chemical Exposure–Job Exposure Matrix (ACE JEM)), were used. The outcome measures were participants with T2DM and dementia. In appropriately adjusted models, environmental exposure to PM2.5 was associated with an odds ratio (OR) of 1.02 (95% CI 1.00 to 1.03) per unit exposure for developing T2DM, while PM2.5 was associated with an odds ratio of 1.06 (95% CI 0.96 to 1.16) per unit exposure for developing dementia. These environmental results align with existing findings in the published literature. Five occupational exposures (dust, fumes, diesel, mineral, and biological dust in the most recent job estimated with the ACE JEM) were investigated and the risks for most exposures for T2DM and for all the exposures for dementia were not significantly increased in the adjusted models. This was confirmed in a subgroup of participants where a full occupational history was available allowed an estimate of workplace exposures. However, when not adjusting for gender, some of the associations become significant, which suggests that there might be a bias between the occupational assessments for men and women. The results of the present study do not provide clear evidence of an association between occupational exposure to particulate matter and T2DM or dementia.
Nursing Home Residents Aged over 80—A Cross-Sectional Analysis on Which Activity Traits Correlate to Positive Affect
Authors: Zirves Melanie , Pfaff Holger
Published: December 2020

Admission to a care facility is assumed to enhance depressive symptoms and dependent behavior in old age. In this context, the relevance of participation in activities that make everyday life in a care facility more pleasant has been pointed out. This study examines if there is a relationship between participation in different activities as well as the frequency of this participation and the positive affect of nursing home residents aged over 80. Data from the unique cross-sectional representative study ‘Quality of life and subjective well-being of the very old in North Rhine-Westphalia’ in Germany (n = 150, aged 90.15 years in average) were used. The data were collected between 08/2017 and 02/2018 using computer-assisted personal interviewing. The variability in and frequency of activity participation functioned as independent, and positive affect as dependent variable. Multiple regression analysis was performed. Residents’ predicted positive affect significantly increased with a higher variability in activity participation. There was no independent effect of frequency in participation. Our findings indicate that there is a significant and positive relationship between participating in a high number of different activities and the overall positive affect of residents aged over 80 years. This does not hold true for the frequency of participation.
Molecular and Biochemical Basis of Fluoroquinolones-Induced Phototoxicity—The Study of Antioxidant System in Human Melanocytes Exposed to UV-A Radiation
Authors: Kowalska Justyna , Banach Klaudia , Rok Jakub , Beberok Artur , Rzepka Zuzanna , Wrześniok Dorota
Published: December 2020

Phototoxicity of fluoroquinolones is connected with oxidative stress induction. Lomefloxacin (8-halogenated derivative) is considered the most phototoxic fluoroquinolone and moxifloxacin (8-methoxy derivative) the least. Melanin pigment may protect cells from oxidative damage. On the other hand, fluoroquinolone–melanin binding may lead to accumulation of drugs and increase their toxicity to skin. The study aimed to examine the antioxidant defense system status in normal melanocytes treated with lomefloxacin and moxifloxacin and exposed to UV-A radiation. The obtained results demonstrated that UV-A radiation enhanced only the lomefloxacin-induced cytotoxic effect in tested cells. It was found that fluoroquinolones alone and with UV-A radiation decreased superoxide dismutase (SOD) activity and SOD1 expression. UV-A radiation enhanced the impact of moxifloxacin on hydrogen peroxide-scavenging enzymes. In turn, lomefloxacin alone increased the activity and the expression of catalase (CAT) and glutathione peroxidase (GPx), whereas UV-A radiation significantly modified the effects of drugs on these enzymes. Taken together, both analyzed fluoroquinolones induced oxidative stress in melanocytes, however, the molecular and biochemical studies indicated the miscellaneous mechanisms for the tested drugs. The variability in phototoxic potential between lomefloxacin and moxifloxacin may result from different effects on the antioxidant enzymes.
Genomics-Assisted Breeding for Quantitative Disease Resistances in Small-Grain Cereals and Maize
Authors: Miedaner Thomas , Boeven Ana Luisa Galiano-Carneiro , Gaikpa David Sewodor , Kistner Maria Belén , Grote Cathérine Pauline
Published: December 2020

Generating genomics-driven knowledge opens a way to accelerate the resistance breeding process by family or population mapping and genomic selection. Important prerequisites are large populations that are genomically analyzed by medium- to high-density marker arrays and extensive phenotyping across locations and years of the same populations. The latter is important to train a genomic model that is used to predict genomic estimated breeding values of phenotypically untested genotypes. After reviewing the specific features of quantitative resistances and the basic genomic techniques, the possibilities for genomics-assisted breeding are evaluated for six pathosystems with hemi-biotrophic fungi: Small-grain cereals/Fusarium head blight (FHB), wheat/Septoria tritici blotch (STB) and Septoria nodorum blotch (SNB), maize/Gibberella ear rot (GER) and Fusarium ear rot (FER), maize/Northern corn leaf blight (NCLB). Typically, all quantitative disease resistances are caused by hundreds of QTL scattered across the whole genome, but often available in hotspots as exemplified for NCLB resistance in maize. Because all crops are suffering from many diseases, multi-disease resistance (MDR) is an attractive aim that can be selected by specific MDR QTL. Finally, the integration of genomic data in the breeding process for introgression of genetic resources and for the improvement within elite materials is discussed.
3D Reconstruction of HvRNASET2 Molecule to Understand Its Antibacterial Role
Authors: Baranzini Nicolò , Pulze Laura , Reguzzoni Marcella , Roncoroni Rossella , Orlandi Viviana Teresa , Tettamanti Gianluca , Acquati Francesco , Grimaldi Annalisa
Published: December 2020

Recent studies performed on the invertebrate model Hirudo verbana (medicinal leech) suggest that the T2 ribonucleic enzyme HvRNASET2 modulates the leech’s innate immune response, promoting microbial agglutination and supporting phagocytic cells recruitment in challenged tissues. Indeed, following injection of both lipoteichoic acid (LTA) and Staphylococcus aureus in the leech body wall, HvRNASET2 is expressed by leech type I granulocytes and induces bacterial aggregation to aid macrophage phagocytosis. Here, we investigate the HvRNASET2 antimicrobial role, in particular assessing the effects on the Gram-negative bacteria Escherichia coli. For this purpose, starting from the three-dimensional molecule reconstruction and in silico analyses, the antibacterial activity was evaluated both in vitro and in vivo. The changes induced in treated bacteria, such as agglutination and alteration in wall integrity, were observed by means of light, transmission and scanning electron microscopy. Moreover, immunogold, AMPs (antimicrobial peptides) and lipopolysaccharide (LPS) binding assays were carried out to evaluate HvRNASET2 interaction with the microbial envelopes and the ensuing ability to affect microbial viability. Finally, in vivo experiments confirmed that HvRNASET2 promotes a more rapid phagocytosis of bacterial aggregates by macrophages, representing a novel molecule for counteracting pathogen infections and developing alternative solutions to improve human health.
Biased Ligands Differentially Shape the Conformation of the Extracellular Loop Region in 5-HT2B Receptors
Authors: Denzinger Katrin , Nguyen Trung Ngoc , Noonan Theresa , Wolber Gerhard , Bermudez Marcel
Published: December 2020

G protein-coupled receptors are linked to various intracellular transducers, each pathway associated with different physiological effects. Biased ligands, capable of activating one pathway over another, are gaining attention for their therapeutic potential, as they could selectively activate beneficial pathways whilst avoiding those responsible for adverse effects. We performed molecular dynamics simulations with known β-arrestin-biased ligands like lysergic acid diethylamide and ergotamine in complex with the 5-HT2B receptor and discovered that the extent of ligand bias is directly connected with the degree of closure of the extracellular loop region. Given a loose allosteric coupling of extracellular and intracellular receptor regions, we delineate a concept for biased signaling at serotonin receptors, by which conformational interference with binding pocket closure restricts the signaling repertoire of the receptor. Molecular docking studies of biased ligands gathered from the BiasDB demonstrate that larger ligands only show plausible docking poses in the ergotamine-bound structure, highlighting the conformational constraints associated with bias. This emphasizes the importance of selecting the appropriate receptor conformation on which to base virtual screening workflows in structure-based drug design of biased ligands. As this mechanism of ligand bias has also been observed for muscarinic receptors, our studies provide a general mechanism of signaling bias transferable between aminergic receptors.
Gastric Adenocarcinomas and Signet-Ring Cell Carcinoma: Unraveling Gastric Cancer Complexity through Microbiome Analysis—Deepening Heterogeneity for a Personalized Therapy
Authors: Ravegnini Gloria , Fosso Bruno , Saverio Viola Di , Sammarini Giulia , Zanotti Federica , Rossi Giulio , Ricci Monica , D’Amico Federica , Valori Giorgia , Ioli Antonella , Turroni Silvia , Brigidi Patrizia , Hrelia Patrizia , Angelini Sabrina
Published: December 2020

Gastric cancer (GC) is the fifth most prevalent cancer worldwide and the third leading cause of global cancer mortality. With the advances of the omic studies, a heterogeneous GC landscape has been revealed, with significant molecular diversity. Given the multifaceted nature of GC, identification of different patient subsets with prognostic and/or predictive outcomes is a key aspect to allow tailoring of specific treatments. Recently, the involvement of the microbiota in gastric carcinogenesis has been described. To deepen this aspect, we compared microbiota composition in signet-ring cell carcinoma (SRCC) and adenocarcinoma (ADC), two distinct GC subtypes. To this purpose, 10 ADC and 10 SRCC and their paired non-tumor (PNT) counterparts were evaluated for microbiota composition through 16S rRNA analysis. Weighted and unweighted UniFrac and Bray–Curtis dissimilarity showed significant community-level separation between ADC and SRCC. Through the LEfSe (linear discriminant analysis coupled with effect size) tool, we identified potential microbial biomarkers associated with GC subtypes. In particular, SRCCs were significantly enriched in the phyla Fusobacteria, Bacteroidetes, Patescibacteria, whereas in the ADC type, Proteobacteria and Acidobacteria phyla were found. Overall, our data add new insights into GC heterogeneity and may contribute to deepening the GC classification.
Development and Maintenance of Epidermal Stem Cells in Skin Adnexa
Authors: Mokry Jaroslav , Pisal Rishikaysh
Published: December 2020

The skin surface is modified by numerous appendages. These structures arise from epithelial stem cells (SCs) through the induction of epidermal placodes as a result of local signalling interplay with mesenchymal cells based on the Wnt–(Dkk4)–Eda–Shh cascade. Slight modifications of the cascade, with the participation of antagonistic signalling, decide whether multipotent epidermal SCs develop in interfollicular epidermis, scales, hair/feather follicles, nails or skin glands. This review describes the roles of epidermal SCs in the development of skin adnexa and interfollicular epidermis, as well as their maintenance. Each skin structure arises from distinct pools of epidermal SCs that are harboured in specific but different niches that control SC behaviour. Such relationships explain differences in marker and gene expression patterns between particular SC subsets. The activity of well-compartmentalized epidermal SCs is orchestrated with that of other skin cells not only along the hair cycle but also in the course of skin regeneration following injury. This review highlights several membrane markers, cytoplasmic proteins and transcription factors associated with epidermal SCs.
Roles and Mechanisms of the Long Noncoding RNAs in Cervical Cancer
Authors: Cáceres-Durán Miguel Ángel , Ribeiro-dos-Santos Ândrea , Vidal Amanda Ferreira
Published: December 2020

Cervical cancer (CC) continues to be one of the leading causes of death for women across the world. Although it has been determined that papillomavirus infection is one of the main causes of the etiology of the disease, genetic and epigenetic factors are also required for its progression. Among the epigenetic factors are included the long noncoding RNAs (lncRNAs), transcripts of more than 200 nucleotides (nt) that generally do not code for proteins and have been associated with diverse functions such as the regulation of transcription, translation, RNA metabolism, as well as stem cell maintenance and differentiation, cell autophagy and apoptosis. Recently, studies have begun to characterize the aberrant regulation of lncRNAs in CC cells and tissues, including Homeobox transcript antisense RNA (HOTAIR), H19, Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), Cervical Carcinoma High-Expressed 1 (CCHE1), Antisense noncoding RNA in the inhibitors of cyclin-dependent kinase 4 (ANRIL), Growth arrest special 5 (GAS5) and Plasmacytoma variant translocation 1 (PVT1). They have been associated with several disease-related processes such as cell growth, cell proliferation, cell survival, metastasis and invasion as well as therapeutic resistance, and are novel potential biomarkers for diagnosis and prognosis in CC. In this review, we summarize the current literature regarding the knowledge we have about the roles and mechanisms of the lncRNAs in cervical neoplasia.
A Sex-Specific Role of Endothelial Sirtuin 3 on Blood Pressure and Diastolic Dysfunction in Female Mice
Authors: Zeng Heng , He Xiaochen , Chen Jian-Xiong
Published: December 2020

Background: Heart failure with preserved ejection fraction (HFpEF) is characterized by a diastolic dysfunction and is highly prevalent in aged women. Our study showed that ablation of endothelial Sirtuin 3 (SIRT3) led to diastolic dysfunction in male mice. However, the sex-specific role of endothelial SIRT3 deficiency on blood pressure and diastolic function in female mice remains to be investigated. Methods and Results: In this study, we demonstrate that the ablation of endothelial SIRT3 in females elevated blood pressure as compared with control female mice. Diastolic function measurement also showed that the isovolumic relaxation time (IVRT) and myocardial performance index (MPI) were significantly increased, whereas the E’ velocity/A’ velocity (E’/A’) ratio was reduced in the endothelial-specific SIRT3 knockout (SIRT3 ECKO) female mice. To further investigate the regulatory role of endothelial SIRT3 on blood pressure and diastolic dysfunction in metabolic stress, SIRT3 ECKO female mice were fed a normal diet and high-fat diet (HFD) for 20 weeks. The knockout of endothelial SIRT3 resulted in an increased blood pressure in female mice fed with an HFD. Intriguingly, SIRT3 ECKO female mice + HFD exhibited impaired coronary flow reserve (CFR) and more severe diastolic dysfunction as evidenced by an elevated IVRT as compared with control female mice + HFD. In addition, female SIRT3 ECKO mice had higher blood pressure and diastolic dysfunction as compared to male SIRT3 ECKO mice. Moreover, female SIRT3 ECKO mice + HFD had an impaired CFR and diastolic dysfunction as compared to male SIRT3 ECKO mice + HFD. Conclusions: These results implicate a sex-specific role of endothelial SIRT3 in regulating blood pressure and diastolic function in mice. Deficiency of endothelial SIRT3 may be responsible for a diastolic dysfunction in aged female.
Ecofriendly Synthesis of Silver Nanoparticles by Terrabacter humi sp. nov. and Their Antibacterial Application against Antibiotic-Resistant Pathogens
Authors: Akter Shahina , Lee Sun-Young , Siddiqi Muhammad Zubair , Balusamy Sri Renukadevi , Ashrafudoulla Md. , Rupa Esrat Jahan , Huq Md. Amdadul
Published: December 2020

It is essential to develop and discover alternative eco-friendly antibacterial agents due to the emergence of multi-drug-resistant microorganisms. In this study, we isolated and characterized a novel bacterium named Terrabacter humi MAHUQ-38T, utilized for the eco-friendly synthesis of silver nanoparticles (AgNPs) and the synthesized AgNPs were used to control multi-drug-resistant microorganisms. The novel strain was Gram stain positive, strictly aerobic, milky white colored, rod shaped and non-motile. The optimal growth temperature, pH and NaCl concentration were 30 °C, 6.5 and 0%, respectively. Based on 16S rRNA gene sequence, strain MAHUQ-38T belongs to the genus Terrabacter and is most closely related to several Terrabacter type strains (98.2%–98.8%). Terrabacter humi MAHUQ-38T had a genome of 5,156,829 bp long (19 contigs) with 4555 protein-coding genes, 48 tRNA and 5 rRNA genes. The culture supernatant of strain MAHUQ-38T was used for the eco-friendly and facile synthesis of AgNPs. The transmission electron microscopy (TEM) image showed the spherical shape of AgNPs with a size of 6 to 24 nm, and the Fourier transform infrared (FTIR) analysis revealed the functional groups responsible for the synthesis of AgNPs. The synthesized AgNPs exhibited strong anti-bacterial activity against multi-drug-resistant pathogens, Escherichia coli and Pseudomonas aeruginosa. Minimal inhibitory/bactericidal concentrations against E. coli and P. aeruginosa were 6.25/50 and 12.5/50 μg/mL, respectively. The AgNPs altered the cell morphology and damaged the cell membrane of pathogens. This study encourages the use of Terrabacter humi for the ecofriendly synthesis of AgNPs to control multi-drug-resistant microorganisms.
Metabolism of Melatonin Synthesis-Related Indoles in the Turkey Pineal Organ and Its Modification by Monochromatic Light
Authors: Martyniuk Kamila , Hanuszewska Maria , Lewczuk Bogdan
Published: December 2020

The metabolism of pineal indoles is closely related to alterations in the light and dark phases of a daily cycle. Recent research showed important interspecies differences in the pineal biochemistry, and a strong impact of monochromatic light on many physiological processes in birds. Therefore, the aims of study were to characterize the metabolism of melatonin-synthesis indoles in the pineal organ of the domestic turkey, and to determine the changes occurring in this metabolism under the influence of different wavelengths and intensities of light. For this purpose, 3-week-old turkeys were kept under 16 lx white light, or under blue, green, and red light with intensities of 16, 32, and 64 lx during the photophase, and after 7 d were sacrificed at 4 h intervals. The activities of melatonin-synthesizing enzymes and the contents of indoles were measured in the same pineal organ. The results revealed that the activities of tryptophan hydroxylase and arylalkylamine N-acetyltransferase, and the levels of all tryptophan derivatives had significant daily changes in birds kept under each light condition used. The profile of pineal indole metabolism in 4-week-old turkeys was characterized by high-amplitude rhythms in the activity of arylalkylamine N-acetyltransferase and the contents of N-acetylserotonin and melatonin, equal relative amounts of serotonin and 5-hydroxyindoleacetic acid, and higher content of melatonin than N-acetylserotonin. The monochromatic light significantly modified the pineal indole metabolism, and its effects were dependent on the color and intensity of light. Pronounced changes occurred in the level of serotonin synthesis and the daily rhythm course of melatonin synthesis.