bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-Year Trend in Escherichia coli Antimicrobial Resistance among Children’s Urine Cultures in an Italian Metropolitan Area
Authors: Pierantoni Luca , Andreozzi Laura , Ambretti Simone , Dondi Arianna , Biagi Carlotta , Baccelli Francesco , Lanari Marcello
Published: July 2021

Urinary tract infections (UTIs) are among the most common bacterial infections in children, and Escherichia coli is the main pathogen responsible. Several guidelines, including the recently updated Italian guidelines, recommend amoxicillin-clavulanic acid (AMC) as a first-line antibiotic therapy in children with febrile UTIs. Given the current increasing rates of antibiotic resistance worldwide, this study aimed to investigate the three-year trend in the resistance rate of E. coli isolated from pediatric urine cultures (UCs) in a metropolitan area of northern Italy. We conducted a retrospective review of E. coli-positive, non-repetitive UCs collected in children aged from 1 month to 14 years, regardless of a diagnosis of UTI, catheter colonization, urine contamination, or asymptomatic bacteriuria. During the study period, the rate of resistance to AMC significantly increased from 17.6% to 40.2% (p < 0.001). Ciprofloxacin doubled its resistance rate from 9.1% to 16.3% (p = 0.007). The prevalence of multidrug-resistant E. coli rose from 3.9% to 9.2% (p = 0.015). The rate of resistance to other considered antibiotics remained stable, as did the prevalence of extended spectrum beta-lactamases and extensively resistant E. coli among isolates. These findings call into question the use of AMC as a first-line therapy for pediatric UTIs in our population, despite the indications of recent Italian guidelines.
PD-Based Optimal ADRC with Improved Linear Extended State Observer
Authors: Zhang Zhen , Cheng Jian , Guo Yinan
Published: July 2021

Taking dead-zone nonlinearlity and external disturbances into account, an active disturbance rejection optimal controller based on a proportional-derivative (PD) control law is proposed by connecting the proportional-integral-derivative (PID) control, the active disturbance rejection control (ADRC) and particle swarm optimization (PSO), with the purpose of providing an efficient and practical technology, and improving the dynamic and steady-state control performances. Firstly, in order to eliminate the negative effects of the dead-zone, a class of 2-order typical single-input single-out system model is established after compensating the dead-zone. Following that, PD control law is introduced to replace the state error feedback control law in ADRC to simplify the control design. By analyzing the characteristics of the traditional linear extended state observer, an improved linear extended state observer is designed, with the purpose of improving the estimation performance of disturbances. Moreover, employing PSO with a designed objective function to optimize parameters of controller to improve control performance. Finally, ten comparative experiments are carried out to verify the effectiveness and superiority of the proposed controller.
Quantum Euler Relation for Local Measurements
Authors: Touil Akram , Weber Kevin , Deffner Sebastian
Published: July 2021

In classical thermodynamics the Euler relation is an expression for the internal energy as a sum of the products of canonical pairs of extensive and intensive variables. For quantum systems the situation is more intricate, since one has to account for the effects of the measurement back action. To this end, we derive a quantum analog of the Euler relation, which is governed by the information retrieved by local quantum measurements. The validity of the relation is demonstrated for the collective dissipation model, where we find that thermodynamic behavior is exhibited in the weak-coupling regime.
Lessons from Postgraduate Supervision in Two African Universities: An Autoethnographic Account
Authors: Daramola Olawande
Published: July 2021

This paper presents an evocative autoethnographic account of my postgraduate supervision experience in two African institutions while dealing mainly with students in the computing disciplines of Computer Science, Information Systems, and Information Technology. In this paper, the context of the postgraduate supervision, and the lessons learnt are presented based on personal reflection, students’ feedback, and retrospective analysis on my activities as an absorbed participant in the supervision process. The reflection of my supervision process offers vital lessons for all supervisors in the developing country context who are torn between the requirements for the student to do quality work and get published in top journals, and the challenges in their operational environment and students’ lives. The study also recommends some good practices that could help supervisors that are operating in similar contexts to mine.
Project-Based Teaching in Organic Chemistry through Blended Learning Model to Develop Self-Study Capacity of High School Students in Vietnam
Authors: Dai Nguyen Van , Trung Vu Quoc , Tiem Chu Van , Hao Kieu Phuong , Anh Dao Thi Viet
Published: July 2021

Developing students’ self-study capacity is an urgent task of high schools in the current educational renovation period in Vietnam. This article presents research findings on developing self-study capacity for students through building and organizing teaching activities of 11th-grade organic chemistry project topics according to the blended learning model. The pedagogical experiment was conducted at three high schools in the north, central, and south regions of Vietnam with 125 students. The data obtained from the teacher’s assessment and the students’ self-assessment showed obvious development of students’ self-study capacity in experimental classes.
Comparative Analysis of Student Engagement in Digital Textbook Use during Quarantine
Authors: Moundy Kamal , Chafiq Nadia , Talbi Mohammed
Published: July 2021

Following the suspension of classes in Morocco due to the health crisis related to COVID-19, an adaptation of the pedagogical intervention of teaching is required. Distance learning is an essential lever contributing to ensuring the educational continuity of students. In this sense, our contribution is to ensure the educational continuity of students during the period of containment through the use of a digital manual. The digital textbook is made available to students of the 1st year of the qualifying secondary education. Through a tracking grid, we measured the student engagement during two different periods without and with the use of the digital textbook. The results show that the digital textbook was able to elicit student engagement in the completion of learning activities with a remarkable improvement of 57.1% in student engagement rate over the two periods (t (273) = 11.059, p < 0.001). Student engagement while using a digital textbook can lead to better academic performance (r = 0.743, p = 0.000 < 0.01). No one can deny the importance of distance learning as a powerful tool that allows teachers to improve their professional practices in the presence of solid, quality instruction in the classroom that promotes the acquisition of skills and the development of competencies in students.
Low Complexity Lane Detection Methods for Light Photometry System
Authors: Suder Jakub , Podbucki Kacper , Marciniak Tomasz , Dąbrowski Adam
Published: July 2021

The aim of the paper was to analyze effective solutions for accurate lane detection on the roads. We focused on effective detection of airport runways and taxiways in order to drive a light-measurement trailer correctly. Three techniques for video-based line extracting were used for specific detection of environment conditions: (i) line detection using edge detection, Scharr mask and Hough transform, (ii) finding the optimal path using the hyperbola fitting line detection algorithm based on edge detection and (iii) detection of horizontal markings using image segmentation in the HSV color space. The developed solutions were tuned and tested with the use of embedded devices such as Raspberry Pi 4B or NVIDIA Jetson Nano.
Deep Collaborative Learning for Randomly Wired Neural Networks
Authors: Essa Ehab , Xie Xianghua
Published: July 2021

A deep collaborative learning approach is introduced in which a chain of randomly wired neural networks is trained simultaneously to improve the overall generalization and form a strong ensemble model. The proposed method takes advantage of functional-preserving transfer learning and knowledge distillation to produce an ensemble model. Knowledge distillation is an effective learning scheme for improving the performance of small neural networks by using the knowledge learned by teacher networks. Most of the previous methods learn from one or more teachers but not in a collaborative way. In this paper, we created a chain of randomly wired neural networks based on a random graph algorithm and collaboratively trained the models using functional-preserving transfer learning, so that the small network in the chain could learn from the largest one simultaneously. The training method applies knowledge distillation between randomly wired models, where each model is considered as a teacher to the next model in the chain. The decision of multiple chains of models can be combined to produce a robust ensemble model. The proposed method is evaluated on CIFAR-10, CIFAR-100, and TinyImageNet. The experimental results show that the collaborative training significantly improved the generalization of each model, which allowed for obtaining a small model that can mimic the performance of a large model and produce a more robust ensemble approach.
Cyberstalking Victimization Model Using Criminological Theory: A Systematic Literature Review, Taxonomies, Applications, Tools, and Validations
Authors: Abu-Ulbeh Waheeb , Altalhi Maryam , Abualigah Laith , Almazroi Abdulwahab Ali , Sumari Putra , Gandomi Amir H.
Published: July 2021

Cyberstalking is a growing anti-social problem being transformed on a large scale and in various forms. Cyberstalking detection has become increasingly popular in recent years and has technically been investigated by many researchers. However, cyberstalking victimization, an essential part of cyberstalking, has empirically received less attention from the paper community. This paper attempts to address this gap and develop a model to understand and estimate the prevalence of cyberstalking victimization. The model of this paper is produced using routine activities and lifestyle exposure theories and includes eight hypotheses. The data of this paper is collected from the 757 respondents in Jordanian universities. This review paper utilizes a quantitative approach and uses structural equation modeling for data analysis. The results revealed a modest prevalence range is more dependent on the cyberstalking type. The results also indicated that proximity to motivated offenders, suitable targets, and digital guardians significantly influences cyberstalking victimization. The outcome from moderation hypothesis testing demonstrated that age and residence have a significant effect on cyberstalking victimization. The proposed model is an essential element for assessing cyberstalking victimization among societies, which provides a valuable understanding of the prevalence of cyberstalking victimization. This can assist the researchers and practitioners for future research in the context of cyberstalking victimization.
PAPR Reduction in OFDM Signals by Self-Adjustment Gain Method
Authors: Hao Miin-Jong , Pi Wei-Wu
Published: July 2021

OFDM in 5G wireless communication networks has the advantages of a high transmission volume and data rate. However, the problem of a high peak-to-average power ratio (PAPR) of OFDM signals may lead to serious performance degradation and distortion in the high-power amplifier at the transmitter. In this paper, with the clipping process, the self-adjustment gain (SAG) method is proposed, to tune up the positions of the clipped signals, for reducing the PAPR of OFDM signals without increasing the error probability. The distance between the estimated and clipped signal points in the signal space is measured. An updated process is developed to produce the new signal points based on the measured distance and the self-adjustment gain that is obtained from the clipping noise power and measurement power. The simulation results show that for QPSK/OFDM, SAG reduces up to 2 dB and 0.7 dB more PAPR than ACE with one and three iterations, respectively. For 16QAM/OFDM, SAG reduces up to 1.3 dB and 0.5 dB more PAPR than ACE with one and three iterations, respectively. SAG also outperforms the active constellation extension, with the projection onto convex sets (ACE-POCS) and gradient project (SGP) methods in first two iterations. Hence, the proposed method really reduces the PAPR value more effectively, within an acceptable error probability, and its computational complexity is also much lower in comparison with those methods based on the active constellation extension (ACE) with iterations.
Approaching Optimal Nonlinear Dimensionality Reduction by a Spiking Neural Network
Authors: Anzueto-Ríos Álvaro , Gómez-Castañeda Felipe , Flores-Nava Luis M. , Moreno-Cadenas José A.
Published: July 2021

This work deals with the presentation of a spiking neural network as a means for efficiently solving the reduction of dimensionality of data in a nonlinear manner. The underneath neural model, which can be integrated as neuromorphic hardware, becomes suitable for intelligent processing in edge computing within Internet of Things systems. In this sense, to achieve a meaningful performance with a low complexity one-layer spiking neural network, the training phase uses the metaheuristic Artificial Bee Colony algorithm with an objective function from the principals in the machine learning science, namely, the modified Stochastic Neighbor Embedding algorithm. To demonstrate this fact, complex benchmark data were used and the results were compared with those generated by a reference network with continuous-sigmoid neurons. The goal of this work is to demonstrate via numerical experiments another method for training spiking neural networks, where the used optimizer comes from metaheuristics. Therefore, the key issue is defining the objective function, which can relate optimally the information at both sides of the spiking neural network. Certainly, machine learning techniques have advanced in defining efficient loss functions that can become suitable objective function candidates in the metaheuristic training phase. The practicality of these ideas is shown in this article. We use MSE values for evaluating the relative quality of the results and also co-ranking matrices.
An 8–12.5-GHz LC PLL with Dual VCO and Noise-Reduced LDO Regulator for Multilane Multiprotocol SerDes in 28-nm CMOS Technology
Authors: Chen Jian , Zhang Wei , Sun Qingqing , Liu Lizheng
Published: July 2021

This study presents an inductance capacitance (LC) phase-locked loop (PLL) with a dual voltage-controlled oscillator (VCO) and a noise-reduced low-dropout (LDO) regulator, which was used in four-lane multiprotocol serial link applications. The dual VCO architecture can increase the total frequency-tuning range to ensure that the LC PLL achieves multiprotocol serial link coverage from 8 to 12.5 Gbps. Two switch capacitor array-based LC VCOs have a large frequency-tuning range and small VCO gain. The noise-reduced LDO regulator provides a very low-noise power supply to the VCO. The active area occupied by the proposed LC PLL in UMC 28-nm 1P10M complementary metal–oxide–semiconductor (CMOS) technology is 0.25 mm2. The phase noise of the VCO at 1 MHz is −108.1 dBc/Hz. The power consumption of the LC PLL with a 1.8-V supply is 16.5 mW.
Feasibility of Grey Water Heat Recovery in Indoor Swimming Pools
Authors: Liebersbach Joanna , Żabnieńska-Góra Alina , Polarczyk Iwona , Sayegh Marderos Ara
Published: July 2021

Swimming pools are used around the world for recreational, rehabilitation and physical activity. From an energy and environmental standpoint, grey water as a waste thermal potential of swimming pools is a valuable heat source produced continuously in extensive, measurable and large quantities. The main objective of this article is to analyse the feasibility of proposed grey water heat recovery (GWHR) system from the showers and backwater from swimming pool filters for an indoor pool located in recreation centre in Poland. Analysis, calculations and results were obtained and discussions of water and energy consumption were carried out for the mentioned indoor swimming pool on the basis of real measurements case study for water flow rate, water temperature in swimming pools and showers. The results ensure a significant potential of energy savings by using the proposed GWHR system, which allows to reduce the energy demand by 34% up to 67% for pool water preheating and domestic hot water (DHW). The environmental impact of proposed GWHR system was analysed and calculated by using Common Air Quality Index. Environmental results are illustrated and discussed specially for the reduction of CO2, NOX, SOX emissions and dust and ensure a significant reduction of these pollutants in range of 34% to 48%.
A Frequency Adaptive Scheme Based on Newton Structure of PRRC for LCL-Type Inverter Connected with Weak Grid
Authors: Zeng Chengbi , Li Sudan , Wang Hanwen , Miao Hong
Published: July 2021

Repetitive control (RC) is gradually used in inverters tied with weak grid. To achieve the zero steady-state error tracking of inverter current and compensate the harmonic distortion caused by frequency fluctuation, a frequency adaptive (FA) control scheme for LCL-type inverter connected with weak grid is proposed. This scheme adopts a proportional resonance (PR) controller in parallel with RC (PRRC) to overcome the disadvantages caused by RC inherent one-cycle time delay. A fractional delay (FD) filter based on the Newton structure is proposed to approximate the fraction item of fs/f, where fs and f are sample frequency and grid frequency, respectively. The structure of the proposed FD filter is relatively simple; moreover, coefficients of the filter maintain constant so as not to need online tuning even when grid frequency fluctuates, which decreases the computational burden considerably. The feasibility and effectiveness of the proposed FA control scheme, named as Newton-FAPRRC, are all verified by the simulation and experimental results.
Environmental Hotspot Assessment for a PV Mini-Grid Design: A Case Study for Malawi
Authors: Lee Jacquetta
Published: July 2021

The United Nations Sustainable Goal 7, access to affordable and clean energy, is unlikely to be achieved, with an estimated 600 million people still without access to electricity by 2030. One potential route to support this goal is through the use of mini-grids to provide electricity in densely populated rural areas for which grid connection is not possible. This paper presents the results of a life cycle assessment of a mini-grid, designed for construction in Malawi. It analyses the cradle to end of use for this mini-grid configuration, for a grid sized for lighting, refrigeration and phone charging, and for a grid sized for electric cooking (e-cooking). The results suggest that for lighting configuration, the main contributors to environmental impact are the poles, the overhead cabling, and the PV panels. The use of a chromium-based preservative is the main issue for the poles, and a switch to concrete poles can deliver significant benefits. When the grid is sized for e-cooking, the PV panels become the greatest contributor. Adding a diesel generator to the mini-grid configuration can reduce number of panels required and hence the environmental impact, but only if the generator is used for no more than 2 h per day.
DC-Link Current Harmonic Mitigation via Phase-Shifting of Carrier Waves in Paralleled Inverter Systems
Authors: Baburajan Silpa , Wang Haoran , Kumar Dinesh , Wang Qian , Blaabjerg Frede
Published: July 2021

DC-connected parallel inverter systems are gaining popularity in industrial applications. However, such parallel systems generate excess current ripple (harmonics) at the DC-link due to harmonic interactions between the inverters in addition to the harmonics from the PWM switching. These DC-link harmonics cause the failure of fragile components such as DC-link capacitors. This paper proposes an interleaving scheme to minimize the current harmonics induced in the DC-link of such a system. First, the optimal phase-shift angle for the carrier signal is investigated using the analytical equations, which provides maximum capacitor current ripple cancellation (i.e., at the main switching frequency harmonic component). These optimally phase-shifted switching cycles lead to variations of the output current ripples, which, when summed together at the DC-link, result in the cancellations of the DC-link current ripples. The results show that when the carrier waves of the two inverters are phase-shifted by a 90° angle, the maximum high-frequency harmonic ripple cancellation occurs, which reduces the overall root-mean-square (RMS) value of the DC-capacitor current by almost 50%. The outcome of this proposed solution is a cost-effective DC-harmonics mitigating strategy for the industrial designers to practically configure multi-inverter systems, even when most of the drives are not operating at rated power levels. The experimental and simulation results presented in this paper verify the effectiveness of the proposed carrier-based phase-shifting scheme for two different configurations of common DC connected multi-converter systems.
Assessment Method to Identify the Potential of Rooftop PV Systems in the Residential Districts
Authors: Odeh Saad , Nguyen Tri Hieu
Published: July 2021

The installation of rooftop PV systems in residential buildings and dwellings has increased rapidly in the past decade, and these systems have become a major source of renewable energy in many countries. This paper presents a new method of estimating the potential of rooftop PV systems to meet energy demands in residential districts by introducing a roof suitability factor. The method of assessment is based on an online tool called SunSPot, which uses a solar radiation heat map layer of building roofs and the PVSYST solar performance software. A sample of 400 houses from four suburbs considered in the Sydney City Council 2030 sustainability plan was selected to conduct the performance analysis of rooftop PV systems and develop a formula that can estimate the suburban annual energy production. The results show that if the dwelling roofs in residential suburbs could be covered by PV arrays it would produce enough electricity to exceed the local electricity demand and, in some suburbs, a surplus of more than 87%.
Characterization of m-GaN and a-GaN Crystallographic Planes after Being Chemically Etched in TMAH Solution
Authors: Al Taradeh Nedal , Frayssinet Eric , Rodriguez Christophe , Morancho Frederic , Sonneville Camille , Phung Luong-Viet , Soltani Ali , Tendille Florian , Cordier Yvon , Maher Hassan
Published: July 2021

This paper proposes a new technique to engineer the Fin channel in vertical GaN FinFET toward a straight and smooth channel sidewall. Consequently, the GaN wet etching in the TMAH solution is detailed; we found that the m-GaN plane has lower surface roughness than crystallographic planes with other orientations, including the a-GaN plane. The grooves and slope (Cuboids) at the channel base are also investigated. The agitation does not assist in Cuboid removal or crystallographic planes etching rate enhancement. Finally, the impact of UV light on m and a-GaN crystal plane etching rates in TMAH has been studied with and without UV light. Accordingly, it is found that the m-GaN plane etching rate is enhanced from 0.69 to 1.09 nm/min with UV light; in the case of a-GaN plane etching, UV light enhances the etching rate from 2.94 to 4.69 nm/min.
A Meta-Level Framework for Evaluating Resilience in Net-Zero Carbon Power Systems with Extreme Weather Events in the United States
Authors: Araújo Kathleen , Shropshire David
Published: July 2021

Important changes are underway in the U.S. power industry in the way that electricity is sourced, transported, and utilized. Disruption from extreme weather events and cybersecurity events is bringing new scrutiny to power-system resilience. Recognizing the complex social and technical aspects that are involved, this article provides a meta-level framework for coherently evaluating and making decisions about power-system resilience. It does so by examining net-zero carbon strategies with quantitative, qualitative, and integrative dimensions across discrete location-specific systems and timescales. The generalizable framework is designed with a flexibility and logic that allows for refinement to accompany stakeholder review processes and highly localized decision-making. To highlight the framework’s applicability across multiple timescales, processes, and types of knowledge, power system outages are reviewed for extreme weather events, including 2021 and 2011 winter storms that impacted Texas, the 2017 Hurricane Maria that affected Puerto Rico, and a heatwave/wildfire event in California in August 2020. By design, the meta-level framework enables utility decision-makers, regulators, insurers, and communities to analyze and track levels of resilience safeguards for a given system. Future directions to advance an integrated science of resilience in net-zero power systems and the use of this framework are also discussed.
Leakage Vortex Progression through a Guide Vane’s Clearance Gap and the Resulting Pressure Fluctuation in a Francis Turbine
Authors: Acharya Nirmal , Gautam Saroj , Chitrakar Sailesh , Trivedi Chirag , Dahlhaug Ole Gunnar
Published: July 2021

A clearance gap (CG) between guide vanes (GVs) and facing plates exists at both ends of a Francis turbine and allows the opening angle to be adjusted for varying operating conditions. Leakage flow is induced through this gap due to the pressure difference between the two sides of the guide vanes. While some research works have used qualitative approaches to visualize and predict the strength of a leakage vortex (LV), this paper presents a method for quantifying vortices along a trajectory. In this paper, a prototype high-head Francis runner with specific speed of 85.4 is considered as a reference case. A systematic investigation across both space and time is carried out, i.e., analysis of the spatial temporal progression of LV for three operating conditions. While travelling from the CG to runner leading edge, LV evolution and trajectory data are observed and the values of vorticity and turbulent kinetic energy are calculated for the LV trajectory. Frequency spectrum analyses of pressure oscillations in the vaneless space, runner blade, and draft tube are also performed to observe the peak pressure pulsation and its harmonics. Unsteady fluctuations of the runner output torque are finally studied to identify the patterns and magnitudes of torque oscillations.
Effective Management Tools for Solving the Problem of Poverty in Relation to Food Waste in Context of Integrated Management of Energy
Authors: Mihalčová Bohuslava , Korauš Antonín , Prokopenko Olha , Hvastová Jozefína , Freňáková Magdaléna , Gallo Peter , Balogová Beáta
Published: July 2021

Globally, millions of people suffer from poverty. This paper discusses the problem of poverty especially in relation to food waste. The prevention of food waste can also contribute to global poverty reduction, and the reduction of food waste is a tool for sustainable growth and competitiveness. At present, the number of people at risk of poverty and the amount of food waste are increasing at unsustainable rates. An integrated and efficient tool for the management of food, energy, and water (FEW) resources to improve FEW security via an interdisciplinary approach could help address several of the most significant global challenges, such as climate change, and economic, environmental, and social security. The aim of this study was to examine the relationship between the existence of poverty and the treatment of food for sustainable growth. The analysis focused on the EU countries and the main data source was the Eurostat database. Households generally create the largest proportion of food waste. Pareto analysis shows that in households, food and non-alcoholic beverages are among the first group of expenses, and in the EU countries they represent approximately 12% of the total expenses. Food and non-alcoholic beverages are a stable, unavoidable, and non-negligible element of total expenses. Paradoxically, enormous amounts of food are wasted. A relatively weak inversely proportional relationship between the amount of food waste per capita and the proportion of the population at risk of poverty among the total population of EU countries was identified through correlational analysis. A very weak relationship between the share of the population at risk of poverty in the total population and the amount of food waste per capita, excluding the population at risk of poverty, was also found.
Assessing Forest Structural and Topographic Effects on Habitat Productivity for the Endangered Apennine Brown Bear
Authors: Rositi Angela Anna , Jona Lasinio Giovanna , Ciucci Paolo
Published: July 2021

Any forest management potentially affects the availability and quality of resources for forest-dwelling wildlife populations, including endangered species. One such species is the Apennine brown bear, a small and unique population living in the central Apennines of Italy. The conservation of this relict bear population is hampered by the lack of knowledge of the fine-scale relationships between productivity of key foods and forest structure, as this prevents the design and implementation of effective forest management plans. To address this issue, we sampled the main structural stand attributes within the bear’s range and used multivariate generalized linear mixed models in a Bayesian framework to relate forest structural attributes to proxies of productivity of key bear foods. We found that hard mast was positively associated with both forest typology and high forest system, but negatively related to both the time elapsed since the last forest utilization and the amount of deadwood. The availability of soft-mast producing species was positively related to past forestry practices but negatively associated with steep slopes historically managed with high tree densities and a low silvicultural disturbance. Our findings also suggest that herb cover was negatively affected by terrain steepness and basal area, while herb productivity was positively affected by northern and southern exposure. Additionally, richness of forest ants was associated with forests characterized by low volume and high density. Our findings confirm that the productivity of natural bear foods is strongly affected by forest structural and topographical characteristics and are relevant as preliminary information for forest management practices to support the long-term conservation of Apennine bears.
Study on the Genetic Structure Based on Geographic Populations of the Endangered Tree Species: Liriodendron chinense
Authors: Zhou Peng-Yan , Hui Li-Xing , Huang Shu-Jing , Ni Zhou-Xian , Yu Fa-Xin , Xu Li-An
Published: July 2021

Liriodendron chinense (Hemsley) Sargent is a Class II protected plant in China as natural populations are on the verge of extinction. There is still a lack of systematic research on the genetic resources of its geographic populations. In this study, we used 20 pairs of SSR markers with high polymorphism to analyze a total of 808 L. chinense samples from 22 regions, and 63 Liriodendron tulipifera Linn samples from 2 regions were used as a comparison group. The results revealed a total of 78 alleles in L. chinense, and the average expected heterozygosity (He) was 0.558, showing a low level of genetic diversity. The degree of differentiation of L. chinense was high, with the differentiation coefficient (Fst) as high as 0.302, which is related to the low gene flow (Nm = 0.578). Based on the genetic structure, principal coordinate analysis (PCoA) and phylogenetic analysis of 24 Liriodendron spp. populations, L. chinense and L. tulipifera had obvious differentiation, while the differentiation between L. chinense geographic populations was very large and irregular. Inbreeding appears within the geographic populations, and the level of genetic diversity is very low. In order to protect the genetic diversity of L. chinense, in addition to protecting the existing population as much as possible, artificial cultivation should introduce materials from multiple populations.
Natural Convection Melting Influence on the Thermal Resistance of a Brick Partially Filled with Phase Change Material
Authors: Bondareva Nadezhda S. , Sheremet Mikhail A.
Published: July 2021

The constant growth of urban agglomerations with the development of transport networks requires the optimal use of energy and new ways of storing it. Energy efficiency is becoming one of the main challenges of modern engineering. The use of phase change materials in construction expands the possibilities of accumulating and storing solar energy, as well as reducing energy consumption. In this study, we consider the problem of the effect of natural convection on heat transfer in a building block containing a phase change material. Heat transfer, taking into account melting in brick, was analyzed at various temperature differences. The mathematical model was formulated in the form of time-dependent equations of conjugate natural convection using non-dimensional stream function, vorticity, and temperature. The equations describing melting, taking into account natural convection, were solved using the finite difference method. Smoothing parameters were used to describe phase transitions in the material. As a result of calculations, local characteristics of heat and mass transfer at various points in time were obtained, as well as changes in temperature profiles on the side surfaces. It is shown that with a large volume of melt, natural convection increases heat loss by more than 10%.
Reelin Alleviates Mesenchymal Stem Cell Senescence and Reduces Pathological α-Synuclein Expression in an In Vitro Model of Parkinson’s Disease
Authors: Cho Eunju , Park Joonsang , Kim Kyungri , Kim Min-Gi , Cho Sung-Rae
Published: July 2021

Parkinson’s disease (PD) is one of the most common neurodegenerative diseases. The mechanisms underlying PD remain to be fully elucidated, and research into treatments for this condition is ongoing. Recent advances in genetic research have shed light on the mechanisms underlying PD. In this study, we used PD and control mesenchymal stem cells (MSCs) obtained from adipose tissues to confirm the differences between groups at the cellular and molecular levels. The results revealed that in PD MSCs, cell viability was clearly lower, and the rate of cell senescence was higher compared to the controls. Next, to compare the gene expression in PD and control cells, transcriptome analysis was performed. Genes in pathways, including extracellular matrix (ECM) receptor interaction, P53 signaling, and focal adhesion, were down-regulated in PD. Among genes related to ECM receptor interaction, RELN gene expression was markedly decreased in PD cells; however, after being treated with recombinant Reelin protein, a significant increase in cell viability and a decrease in α-Synuclein aggregation and cell senescence were observed. In conclusion, Reelin affects PD by positively influencing the cell characteristics. Our findings will facilitate research into new treatments for PD.
Novel Mutation in CRYBB3 Causing Pediatric Cataract and Microphthalmia
Authors: Zin Olivia A. , Neves Luiza M. , Motta Fabiana L. , Horovitz Dafne D. G. , Guida Leticia , Gomes Leonardo H. F. , Cunha Daniela P. , Rodrigues Ana Paula S. , Zin Andrea A. , Sallum Juliana M. F. , Vasconcelos Zilton F. M.
Published: July 2021

Up to 25% of pediatric cataract cases are inherited, with half of the known mutant genes belonging to the crystallin family. Within these, crystallin beta B3 (CRYBB3) has the smallest number of reported variants. Clinical ophthalmological and genetic-dysmorphological evaluation were performed in three autosomal dominant family members with pediatric cataract and microphthalmia, as well as one unaffected family member. Peripheral blood was collected from all participating family members and next-generation sequencing was performed. Bioinformatics analysis revealed a novel missense variant c.467G>A/p.Gly156Glu in CRYBB3 in all family members with childhood cataract. This variant is classified as likely pathogenic by ACMG, and no previous descriptions of it were found in ClinVar, HGMD or Cat-Map. The only other mutation previously described in the fifth exon of CRYBB3 is a missense variant that causes a change in amino acid from the same 156th amino acid to arginine and has been associated with pediatric cataract and microphthalmia. To the best of our knowledge, this is the first time the c.467G>A/p.Gly156Glu variant is reported and the second time a mutation in CRYBB3 has been associated with microphthalmia.
SARS-CoV-2 Infection and Emery-Dreifuss Syndrome in a Young Patient with a Family History of Dilated Cardiomyopathy
Authors: Dumitru Irina Magdalena , Vlad Nicoleta Dorina , Rugina Sorin , Onofrei Nicoleta , Gherca Sabina , Raduna Marian , Trana Aurel , Dumitrascu Mirela , Popovici Elena , Bajdechi Mircea , Zekra Lucia , Cernat Roxana Carmen
Published: July 2021

Emery–Dreifuss muscular dystrophy (EDMD) is a rare genetic disease that affects the musculoskeletal system, including the heart, causing rhythm disorders and cardiomyopathy, sometimes requiring an implantable cardioverter-defibrillator (ICD) or heart transplantation due to severe heart damage. The case described herein concerns a 16-year-old girl, with grade II obesity, without other known pathological antecedents or cardiac pathology diagnosis given an annual history of cardiological investigations. She was admitted to the Infectious Diseases Department with SARS-CoV-2 virus infection. The anamnesis showed that the cardiological investigations performed in the past were completed due to the medical history antecedents of her sister, who had been diagnosed with dilated cardiomyopathy, having undergone the placement of an ICD and a heart transplant. Numerous investigations were performed during hospitalization, which revealed high levels of high-sensitive cardiac troponin I (hs-cTnI), creatine kinase (CK) and N-terminal pro b-type natriuretic peptide (NT-proBNP). Dynamic electrocardiographic evaluations showed ventricular extrasystoles, without clinical manifestations. The patient presented stage 2 arterial hypertension (AHT) during hospitalization. A cardiac ultrasound was also performed, which revealed suspected mild subacute viral myocarditis with cardiomyopathy, and antihypertensive medication was initiated. A heart MRI was performed, and the patient was diagnosed with dilated cardiomyopathy, refuting the suspicion of viral subacute myocarditis. After discharge, as the patient developed gait disorders with an impossible heel strike upon walking and limitation of the extension of the arms and ankles, was hospitalized in the Neurology Department. Electrocardiograms (ECGs) were dynamically performed, and because the rhythm disorders persisted, the patient was transferred to the Cardiology Department. On Holter monitoring, non-sustained ventricular tachycardia (NSVT) was detected, so antiarrhythmic treatment was initiated, and placement of an ICD was subsequently decided and was diagnosed with EDMD. Genetic tests were also performed, and a mutation of the lamin A/C gene was detected (LMNA gene exon 2, variant c448A > C (p.Thr150pro), heterozygous form, AD).
Children’s Activity Classification for Domestic Risk Scenarios Using Environmental Sound and a Bayesian Network
Authors: García-Domínguez Antonio , Galván-Tejada Carlos E. , Brena Ramón F. , Aguileta Antonio A. , Galván-Tejada Jorge I. , Gamboa-Rosales Hamurabi , Celaya-Padilla José M. , Luna-García Huizilopoztli
Published: July 2021

Children’s healthcare is a relevant issue, especially the prevention of domestic accidents, since it has even been defined as a global health problem. Children’s activity classification generally uses sensors embedded in children’s clothing, which can lead to erroneous measurements for possible damage or mishandling. Having a non-invasive data source for a children’s activity classification model provides reliability to the monitoring system where it is applied. This work proposes the use of environmental sound as a data source for the generation of children’s activity classification models, implementing feature selection methods and classification techniques based on Bayesian networks, focused on the recognition of potentially triggering activities of domestic accidents, applicable in child monitoring systems. Two feature selection techniques were used: the Akaike criterion and genetic algorithms. Likewise, models were generated using three classifiers: naive Bayes, semi-naive Bayes and tree-augmented naive Bayes. The generated models, combining the methods of feature selection and the classifiers used, present accuracy of greater than 97% for most of them, with which we can conclude the efficiency of the proposal of the present work in the recognition of potentially detonating activities of domestic accidents.
Nystagmus Estimation for Dizziness Diagnosis by Pupil Detection and Tracking Using Mexican-Hat-Type Ellipse Pattern Matching
Authors: Syahbana Yoanda Alim , Yasunari Yokota , Hiroyuki Morita , Mitsuhiro Aoki , Kanade Suzuki , Yoshitaka Matsubara
Published: July 2021

The detection of nystagmus using video oculography experiences accuracy problems when patients who complain of dizziness have difficulty in fully opening their eyes. Pupil detection and tracking in this condition affect the accuracy of the nystagmus waveform. In this research, we design a pupil detection method using a pattern matching approach that approximates the pupil using a Mexican hat-type ellipse pattern, in order to deal with the aforementioned problem. We evaluate the performance of the proposed method, in comparison with that of a conventional Hough transform method, for eye movement videos retrieved from Gifu University Hospital. The performance results show that the proposed method can detect and track the pupil position, even when only 20% of the pupil is visible. In comparison, the conventional Hough transform only indicates good performance when 90% of the pupil is visible. We also evaluate the proposed method using the Labelled Pupil in the Wild (LPW) data set. The results show that the proposed method has an accuracy of 1.47, as evaluated using the Mean Square Error (MSE), which is much lower than that of the conventional Hough transform method, with an MSE of 9.53. We conduct expert validation by consulting three medical specialists regarding the nystagmus waveform. The medical specialists agreed that the waveform can be evaluated clinically, without contradicting their diagnoses.
The Hierarchy of Walking Needs and the COVID-19 Pandemic
Authors: Paydar Mohammad , Kamani Fard Asal
Published: July 2021

More than 150 cities around the world have expanded emergency cycling and walking infrastructure to increase their resilience in the face of the COVID 19 pandemic. This tendency toward walking has led it to becoming the predominant daily mode of transport that also contributes to significant changes in the relationships between the hierarchy of walking needs and walking behaviour. These changes need to be addressed in order to increase the resilience of walking environments in the face of such a pandemic. This study was designed as a theoretical and empirical literature review seeking to improve the walking behaviour in relation to the hierarchy of walking needs within the current context of COVID-19. Accordingly, the interrelationship between the main aspects relating to walking-in the context of the pandemic- and the different levels in the hierarchy of walking needs were discussed. Results are presented in five sections of “density, crowding and stress during walking”, “sense of comfort/discomfort and stress in regard to crowded spaces during walking experiences”, “crowded spaces as insecure public spaces and the contribution of the type of urban configuration”, “role of motivational/restorative factors during walking trips to reduce the overload of stress and improve mental health”, and “urban design interventions on arrangement of visual sequences during walking”.
Recreational Screen Time and Anxiety among College Athletes: Findings from Shanghai
Authors: Gao Yu , Fu Ning , Mao Yuping , Shi Lu
Published: July 2021

To better understand the behavioral factors contributing to the mental health status among student athletes, we examined the link between recreational screen time and college student athlete’s anxieties. This cross-sectional study was conducted among 278 college student athletes from Shanghai, China, aged between 17 and 25 years old (M = 19.4, SD = 1.5). Multivariate regression analyses, controlled for age, gender, rural vs. urban residency, and individual vs. team sports factors, were performed to analyze the association between their average daily recreational screen time in a week and their dispositional anxiety, pre-competition anxiety, and anxiety during competition, which were measured by the Chinese version of validated psychometric scales among athlete population. Significant results were found in both dispositional anxiety and situational anxiety in relation to recreational screen time among college athletes. Conclusions: Our findings indicate that excessive recreational screen time is a risk indicator of college student athletes’ dispositional anxiety, pre-competition anxiety, and anxiety during competition.
DIAPH2, PTPRD and HIC1 Gene Polymorphisms and Laryngeal Cancer Risk
Authors: Śnit Mirosław , Misiołek Maciej , Ścierski Wojciech , Koniewska Anna , Stryjewska-Makuch Grażyna , Okła Sławomir , Grzeszczak Władysław
Published: July 2021

AIM, DIAPH2, PTPRD and HIC1 are the cell glycoprotein, which play an important role in the occurrence and development of tumors. This study was designed to assess the association between DIAPH2, PTPRD and HIC1 SNPs and laryngeal cancer risk. PATIENTS AND METHODS: This study including 267 patients with histologically confirmed laryngeal cancer and 157 controls. The relationship between genetic variations DIAPH2 (rs6620138), PTPRD (rs3765142) and HIC1 (rs9901806) and the onset of laryngeal cancer were investigated. Statistical analysis to calculate the relationship between DIAPH2, PTPRD and HIC1 genes polymorphism and pathogenesis of laryngeal cancer. RESULTS: The results showed that rs6620138 DIAPH2 polymorphism could increase the onset risk of laryngeal cancer. Statistically significant differences in allele distribution of rs6620138 DIAPH2 and rs9901806 HIC1 in the case and control groups subgroups. CONCLUSIONS: This study results suggested that genetic variation of rs6620138 DIAPH2 polymorphism is related to the susceptibility to laryngeal cancer. Our results provide a basis to begin basic research on the role of DIAPH2 gene in the pathogenesis of laryngeal cancer.