bluuebunny/crossref_metadata_2025 huggingface dataset:
Antibiotics Prescription by Spanish General Practitioners in Primary Dental Care
Authors: Domínguez-Domínguez Laura , López-Marrufo-Medina Alfonso , Cabanillas-Balsera Daniel , Jiménez-Sánchez María Carmen , Areal-Quecuty Victoria , López-López José , Segura-Egea Juan. J. , Martin-González Jenifer
Published: June 2021

The aim of this study was to analyze the antibiotics prescription habits, both prophylactically and therapeutically, of Spanish general dental practitioners in the management of endodontic infections in primary care. Two hundred Spanish general dental practitioners were asked to respond to a survey on indications for antibiotics prescription in the treatment of endodontic infections, being 190 general dentists (95%) included in the study. Data were analyzed using descriptive statistics and the chi-square test. The average duration of antibiotics therapy was 6.5 ± 1.0 days. In patients without medical allergies, most of them (97%) selected amoxicillin as the antibiotic of the first choice, alone (51.1%) or associated with clavulanic acid (45.8%); in patients with penicillin allergies, the drug of choice was clindamycin 300 mg (70%). For cases of symptomatic irreversible pulpitis, 44% of the respondents prescribed antibiotics, in the scenario of prophylactic antibiotic prescription, up to 27% of the general dentists prescribe according to non-current guidelines (1 g 1 h before or 1 g 1 h before and 1 g 1 h after) in non-indicated cases (16% in patients taking oral bisphosphonates). It is necessary to improve the antibiotic prescription habits of Spanish general dentists in endodontics.
Antibiotic Susceptibility, Virulome, and Clinical Outcomes in European Infants with Bloodstream Infections Caused by Enterobacterales
Authors: Folgori Laura , Di Carlo Domenico , Comandatore Francesco , Piazza Aurora , Witney Adam A. , Bresesti Ilia , Hsia Yingfen , Laing Kenneth , Monahan Irene , Bielicki Julia , Alvaro Alessandro , Zuccotti Gian Vincenzo , Planche Tim , Heath Paul T. , Sharland Mike
Published: June 2021

Mortality in neonates with Gram-negative bloodstream infections has remained unacceptably high. Very few data are available on the impact of resistance profiles, virulence factors, appropriateness of empirical treatment and clinical characteristics on patients’ mortality. A survival analysis to investigate 28-day mortality probability and predictors was performed including (I) infants <90 days (II) with an available Enterobacterales blood isolate with (III) clinical, treatment and 28-day outcome data. Eighty-seven patients were included. Overall, 299 virulence genes were identified among all the pathogens. Escherichia coli had significantly more virulence genes identified compared with other species. A strong positive correlation between the number of resistance and virulence genes carried by each isolate was found. The cumulative probability of death obtained by the Kaplan-Meier survival analysis was 19.5%. In the descriptive analysis, early age at onset, gestational age at onset, culture positive for E. coli and number of classes of virulence genes carried by each isolate were significantly associated with mortality. By Cox multivariate regression, none of the investigated variables was significant. This pilot study has demonstrated the feasibility of investigating the association between neonatal sepsis mortality and the causative Enterobacterales isolates virulome. This relationship needs further exploration in larger studies, ideally including host immunopathological response, in order to develop a tailor-made therapeutic strategy.
Pre-Treatment with Grape Seed Extract Reduces Inflammatory Response and Oxidative Stress Induced by Helicobacter pylori Infection in Human Gastric Epithelial Cells
Authors: Silvan Jose Manuel , Gutierrez-Docio Alba , Guerrero-Hurtado Esperanza , Domingo-Serrano Lucia , Blanco-Suarez Ana , Prodanov Marin , Alarcon-Cavero Teresa , Martinez-Rodriguez Adolfo J.
Published: June 2021

Helicobacter pylori (H. pylori) is a pathogenic bacteria identified as a potential risk factor for gastritis, gastric ulcers and gastric cancer. During the stomach colonization, H. pylori triggers a strong inflammatory response and subsequent oxidative stress, which are associated with tissue damage. For this reason, it is of particular interest to develop alternative natural tools that enable modulation of the associated damaging immune response. With this purpose, we obtained grape seed extract (GSE) from sweet (not fermented) food grade seeds. The aim of our study was to investigate the effect of GSE and its two enriched procyanidins fractions (OPC and PPC) on the inflammatory process and oxidative stress produced by different H. pylori strains in human gastric epithelial cells (AGS). Anti-inflammatory activity was evaluated by measuring the level of interleukin-8 (IL-8) secretion. IL-8 production was significantly reduced in H. pylori-infected human gastric epithelial cells pre-treated with GSE or its enriched fractions when compared with non-pre-treated infected cells (from 21.6% to 87.8%). Pre-treatment with GSE or its fractions significantly decreased intracellular reactive oxygen species (ROS) production in AGS cells after infection, depending on the H. pylori strain. Our results also showed that GSE and its fractions demonstrate antibacterial activity against all strains of H. pylori used in the study. This work demonstrates the effectiveness of GSE enriched in procyanidins against the main events associated with H. pylori infection.
Specificity of Human Sulfiredoxin for Reductant and Peroxiredoxin Oligomeric State
Authors: Forshaw Tom E. , Reisz Julie A. , Nelson Kimberly J. , Gumpena Rajesh , Lawson J. Reed , Jönsson Thomas J. , Wu Hanzhi , Clodfelter Jill E. , Johnson Lynnette C. , Furdui Cristina M. , Lowther W. Todd
Published: June 2021

Human peroxiredoxins (Prx) are a family of antioxidant enzymes involved in a myriad of cellular functions and diseases. During the reaction with peroxides (e.g., H2O2), the typical 2-Cys Prxs change oligomeric structure between higher order (do)decamers and disulfide-linked dimers, with the hyperoxidized inactive state (-SO2H) favoring the multimeric structure of the reduced enzyme. Here, we present a study on the structural requirements for the repair of hyperoxidized 2-Cys Prxs by human sulfiredoxin (Srx) and the relative efficacy of physiological reductants hydrogen sulfide (H2S) and glutathione (GSH) in this reaction. The crystal structure of the toroidal Prx1-Srx complex shows an extended active site interface. The loss of this interface within engineered Prx2 and Prx3 dimers yielded variants more resistant to hyperoxidation and repair by Srx. Finally, we reveal for the first time Prx isoform-dependent use of and potential cooperation between GSH and H2S in supporting Srx activity.
Correction: Gómez-Cruz et al. Valorisation of Exhausted Olive Pomace by an Eco-Friendly Solvent Extraction Process of Natural Antioxidants. Antioxidants 2020, 9, 1010
Authors: Gómez-Cruz Irene , Cara Cristóbal , Romero Inmaculada , Castro Eulogio , Gullón Beatriz
Published: June 2021

The author wishes to make the following correction to this paper [...]
Early Performance Prediction in Bioinformatics Systems Using Palladio Component Modeling
Authors: Dorgham Doaa M. Talaat , Belal Nahla A. , Abdelmoez Walid
Published: June 2021

Bioinformatics is a branch of science that uses computers, algorithms, and databases to solve biological problems. To achieve more accurate results, researchers need to use large and complex datasets. Sequence alignment is a well-known field of bioinformatics that allows the comparison of different genomic sequences. The comparative genomics field allows the comparison of different genomic sequences, leading to benefits in areas such as evolutionary biology, agriculture, and human health (e.g., mutation testing connects unknown genes to diseases). However, software engineering best practices, such as software performance engineering, are not taken into consideration in most bioinformatics tools and frameworks, which may lead to serious performance problems. Having an estimate of the software performance in the early phases of the Software Development Life Cycle (SDLC) is beneficial in making better decisions relating to the software design. Software performance engineering provides a reliable and observable method to build systems that can achieve their required performance goals. In this paper, we introduce the use of the Palladio Component Modeling (PCM) methodology to predict the performance of a sequence alignment system. Software performance engineering was not considered during the original system development. As a result of the performance analysis, an alternative design is proposed. Comparing the performance of the proposed design against the one already developed, a better response time is obtained. The response time of the usage scenario is reduced from 16 to 8.6 s. The study results show that using performance models at early stages in bioinformatics systems can help to achieve better software system performance.
Spinel Iron Oxide by the Co-Precipitation Method: Effect of the Reaction Atmosphere
Authors: Slimani Sawssen , Meneghini Carlo , Abdolrahimi Maryam , Talone Alessandro , Murillo Jean Pierre Miranda , Barucca Gianni , Yaacoub Nader , Imperatori Patrizia , Illés Erzsébet , Smari Mourad , Dhahri Essebti , Peddis Davide
Published: June 2021

Synthesis atmosphere (i.e., air and nitrogen) effects on the physical properties and formation mechanism of spinel iron oxide nanoparticles prepared via the co-precipitation method have been investigated using a multi-technique approach. The obtained magnetic nanoparticles (MNPs) were characterized using the X-ray diffraction, transmission electron microscopy (TEM), SQUID magnetometry, Mössbauer spectroscopy and X-ray absorption near-edge Structure spectroscopy techniques. The synthesis procedure leads to the formation of a spinel structure with an average crystallite size of 9.0(9) nm. The morphology of the particles synthetized under an inert atmosphere was quasi-spherical, while the nanoparticles prepared in air present a faceted shape. The small differences observed in morphological properties are explained by the influence of the reaction atmosphere on the formation mechanism of the MNPs. The magnetic characterization indicates that both samples exhibit superparamagnetic behavior at 300 K. The investigation by means of the Langevin approach at 300 K also leads to equal values for the mean size of the magnetic cores (Dm). Additionally, the analysis of the Mössbauer spectra revealed the lack of spin disorder for both samples, resulting in a high saturation magnetization. The fit of XANES spectrum suggests that about 2/3 of the iron ions reside in a local environment close to that of γ-Fe2O3 and about 1/3 close to that of Fe3O4 for the sample synthetized in inert atmosphere.
A Neural Network Model for Decision-Making with Application in Sewage Sludge Management
Authors: Facchini Francesco , Ranieri Luigi , Vitti Micaela
Published: June 2021

Wastewater treatment (WWT) is a foremost challenge for maintaining the health of ecosystems and human beings; the waste products of the water-treatment process can be a problem or an opportunity. The sewage sludge (SS) produced during sewage treatment can be considered a waste to be disposed of in a landfill or as a source for obtaining raw material to be used as a fertilizer, building material, or alternative fuel source suitable for co-incineration in a high-temperature furnace. To this concern, this study’s purpose consisted of developing a decision model, supported by an Artificial Neural Network (ANN model), allowing us to identify the most effective sludge management strategy in economic terms. Consistent with the aim of the work, the suitable SS treatment was identified, selecting for each phase of the SS treatment, an alternative available on the market ensuring energy and/or matter recovery, in line with the circular water value chain. Results show that the ANN model identifies the suitable SS treatments on multiple factors, thus supporting the decision-making and identifying the solution as per user requirements.
Preliminary Design of the Electrical Power Systems for DTT Nuclear Fusion Plant
Authors: Caldora Marzia , Falvo Maria Carmen , Lampasi Alessandro , Marelli Gianluca
Published: June 2021

The realization of the Divertor Tokamak Test (DTT) facility is one of the key milestones of the European Roadmap, aiming to explore alternative power exhaust solutions for DEMO, the first nuclear-fusion power plant that will be connected to the European grid. For the actual implementation of the DTT and DEMO plants, it is necessary to define the structure of the internal electric power distribution system, able to supply unconventional loads with a sufficient level of reliability. The present paper reports the preliminary studies for the feasibility and realization of the electrical power systems of DTT, describing the methodology adopted to obtain a first distribution configuration and providing some simulation results. In particular, the first stage of the study deals with the survey and characterization of the electrical loads, which allows defining a general layout of the facility and size the main electrical components. To verify the correctness of the assumptions, simulation models of the grid were implemented in the DIgSILENT PowerFactory software in order to carry out power flow and fault analyses.
Modelling the Activation Pathways in Full-Length Src Kinase
Authors: Alba Josephine , Montagna Maria , D’Abramo Marco
Published: June 2021

Src kinases play fundamental roles in several crucial cell processes. Their activity is tightly regulated by conformational transitions between the active and the inactive forms, which are carried out by complex protein structural rearrangements. Here, we present an in-depth study of such structural transitions coupling extensive all-atoms molecular dynamic simulations coupled to an algorithm able to drive the system between defined conformational states. Our results, in line with the available experimental data, confirm the complexity of such a process indicating the main molecular determinants involved. Moreover, the role of an Src inhibitor—able to bind to the protein inactive state—is discussed and compared with available experimental data.
Informal Learning Spaces in Higher Education: Student Preferences and Activities
Authors: Wu Xianfeng , Kou Zhipeng , Oldfield Philip , Heath Tim , Borsi Katharina
Published: June 2021

Informal learning spaces play a significant role in enriching student experiences in learning environments. Such spaces are becoming more common, resulting in a change to the spatial configuration of built environments in higher education. However, previous research lacks methods to evaluate the influence of the spatial design characteristics of informal learning spaces on student preferences and their activities within. This paper aims to tease out the spatial design characteristics of informal learning spaces to examine how they shape students’ preferences in terms of their use of the spaces and what they do within them. The two case studies selected for this study, both in the UK, are the Diamond at the University of Sheffield, and the Newton at Nottingham Trent University. A mixed-methods study is applied, including questionnaires, observation, interviews, and focus groups. Six significant design characteristics (comfort, flexibility, functionality, spatial hierarchy, openness, and other support facilities) that influence student use of informal learning environments are identified. These can be used to inform future design strategies for other informal learning spaces in higher education.
Learning from Failures: Reflections on the Role of Project Design and Design Management in the Procurement of Non-Standard Buildings
Authors: Cardellicchio Luciano , Tombesi Paolo
Published: June 2021

The opening of the Guggenheim Museum in Bilbao in 1997 heralded the beginning of an era in world architecture defined by iconic buildings underpinned by mediatic exposure and the belief in the power of design to leverage urban conditions. Today, a conspicuous number of such buildings featuring non-standard geometries are experiencing accelerated forms of decay with the emergence of construction defects. This study compares the type of problems encountered in the Jubilee Church in Rome (1996–2003), analysed in previous studies, with the failures of other two contemporary buildings of analogous features, namely: the Palau de les Arts Reina Sofia in Valencia (1996–2005) and the Museum of the Arts of the XXI Century in Rome (1998–2010). The findings of the study show that the accelerated decay of the three buildings shares familiar features and common challenges: geometry of the façade, local environmental factors, labour organisation, and limited regard of maintenance principles. Building on the patterns identified here, the paper suggests structural reasons for their emergence and speculates on the potential benefits deriving from the amplification of the design function.
Case Series of Multisystem Inflammatory Syndrome (MIS-C) in Children during the SARS-CoV-2 Pandemic in Latvia
Authors: Racko Iveta , Smane Liene , Klavina Lizete , Pucuka Zanda , Roge Ieva , Pavare Jana
Published: June 2021

The total number of COVID-19 positive cases in Latvia has escalated rapidly since October 2020, peaking in late December 2020 and early January 2021. Children generally develop COVID-19 more mildly than adults; however, it can be complicated by multisystem inflammatory syndrome in children (MIS-C). This case study aims were to assess demographic characteristics and the underlying medical conditions, and clinical, investigative and treatment data among 13 MIS-C patients using electronic medical records. All 13 had acute illness or contact with someone who was COVID-19 positive two to six weeks before MIS-C onset. Only five of the 13 were symptomatic during the acute COVID-19 phase. The median age was 8.8 years; 11/13 patients were male, 10/13 had been previously healthy, and all 13 patients tested positive for SARS-CoV-2 by RT-PCR or antibody testing. The most commonly involved organ systems were the gastrointestinal (13/13), hematologic (13/13), cardiovascular (13/13), skin and mucosa (13/13), and respiratory (12/13) ones. The median hospital stay was 13 (interquartile range, 11 to 18) days; 7/13 patients received intensive care, 6/13 oxygen support, and 5/13 received inotropic support. No deaths occurred. During the current pandemic, every child with a fever should have a clearly defined epidemiological history of COVID-19, a careful clinical assessment of possible multiple organ-system involvement, with a special focus on children with severe abdominal pain and/or skin and mucocutaneous lesions.
Functional Design Employing Miniaturized Electronics with Wireless Signal Provision to a Smartphone for a Strain-Based Measuring System for Ski Poles
Authors: Hentschel Uwe , Steinbild Philip Johannes , Dannemann Martin , Schwaar Andree , Modler Niels , Schürer Axel
Published: June 2021

The individual monitoring of cross-country skiers’ technique-related parameters is crucial to identifying possible athlete-individual deficits that need to be corrected in order to optimize the athlete’s performance in competition. To be able to record relevant biomechanical parameters during training in the field, the development of measuring systems exploiting the athlete’s full potential is the key. Known mobile monitoring systems for measuring forces on ski poles use comparably heavy uniaxial load cells mounted on the pole with a data logger also attached to the pole or carried by the athlete. Measurements that are more accurate can be acquired using wire-based systems. However, wire-based systems are highly immobile and only usable when the athletes undergo a stationary test, e.g., on a treadmill. This paper focuses on the functional design of a measuring system using specialized, miniaturized electronics for acquiring data from strain sensors. These data are then used to determine the technique-related parameters pole force and angle of bend. The functional design is also capable of transmitting the acquired data wirelessly via Bluetooth to a smartphone that runs a proprietary app. This approach is advantageous regarding mass, dynamic behavior, analyzing functionality, and signal processing compared to the state of the art.
Understanding Motor Skill Learning as Related to Dentistry
Authors: El-Kishawi Mohamed , Khalaf Khaled , Winning Tracey
Published: June 2021

Learning dental procedures is a complex task involving the development of fine motor skills. The reported use of theories and/or evidence for designing learning activities to develop the fine motor skills needed for dental practice is limited. The aim of this review is to explore the available body of knowledge related to learning motor skills relevant to dentistry. Evidence from studies investigating motor skill learning highlights the negative impact of self-focus and self-regulation on learning outcomes, particularly during the early stages of learning. The development of activities and schedules that enable novices to demonstrate characteristics similar to experts, without the reported long period of ‘deliberate practice’, is clearly of value. Outcomes of learning implicitly are important in dentistry because working under stressful conditions is common, either during undergraduate study or in practice. It is suggested that learning implicitly in the simulation stage can reduce disrupted performance when transitioning to clinical settings. Therefore, further investigation of effective methods for learning dental fine motor skills is indicated, using approaches that result in robust performance, even under stressful conditions.
Improved Q-Learning Algorithm Based on Approximate State Matching in Agricultural Plant Protection Environment
Authors: Sun Fengjie , Wang Xianchang , Zhang Rui
Published: June 2021

An Unmanned Aerial Vehicle (UAV) can greatly reduce manpower in the agricultural plant protection such as watering, sowing, and pesticide spraying. It is essential to develop a Decision-making Support System (DSS) for UAVs to help them choose the correct action in states according to the policy. In an unknown environment, the method of formulating rules for UAVs to help them choose actions is not applicable, and it is a feasible solution to obtain the optimal policy through reinforcement learning. However, experiments show that the existing reinforcement learning algorithms cannot get the optimal policy for a UAV in the agricultural plant protection environment. In this work we propose an improved Q-learning algorithm based on similar state matching, and we prove theoretically that there has a greater probability for UAV choosing the optimal action according to the policy learned by the algorithm we proposed than the classic Q-learning algorithm in the agricultural plant protection environment. This proposed algorithm is implemented and tested on datasets that are evenly distributed based on real UAV parameters and real farm information. The performance evaluation of the algorithm is discussed in detail. Experimental results show that the algorithm we proposed can efficiently learn the optimal policy for UAVs in the agricultural plant protection environment.
Computing Accurate Probabilistic Estimates of One-D Entropy from Equiprobable Random Samples
Authors: Gupta Hoshin V. , Ehsani Mohammad Reza , Roy Tirthankar , Sans-Fuentes Maria A. , Ehret Uwe , Behrangi Ali
Published: June 2021

We develop a simple Quantile Spacing (QS) method for accurate probabilistic estimation of one-dimensional entropy from equiprobable random samples, and compare it with the popular Bin-Counting (BC) and Kernel Density (KD) methods. In contrast to BC, which uses equal-width bins with varying probability mass, the QS method uses estimates of the quantiles that divide the support of the data generating probability density function (pdf) into equal-probability-mass intervals. And, whereas BC and KD each require optimal tuning of a hyper-parameter whose value varies with sample size and shape of the pdf, QS only requires specification of the number of quantiles to be used. Results indicate, for the class of distributions tested, that the optimal number of quantiles is a fixed fraction of the sample size (empirically determined to be ~0.25–0.35), and that this value is relatively insensitive to distributional form or sample size. This provides a clear advantage over BC and KD since hyper-parameter tuning is not required. Further, unlike KD, there is no need to select an appropriate kernel-type, and so QS is applicable to pdfs of arbitrary shape, including those with discontinuous slope and/or magnitude. Bootstrapping is used to approximate the sampling variability distribution of the resulting entropy estimate, and is shown to accurately reflect the true uncertainty. For the four distributional forms studied (Gaussian, Log-Normal, Exponential and Bimodal Gaussian Mixture), expected estimation bias is less than 1% and uncertainty is low even for samples of as few as 100 data points; in contrast, for KD the small sample bias can be as large as −10% and for BC as large as −50%. We speculate that estimating quantile locations, rather than bin-probabilities, results in more efficient use of the information in the data to approximate the underlying shape of an unknown data generating pdf.
Radar-Based Hand Gesture Recognition Using Spiking Neural Networks
Authors: Tsang Ing Jyh , Corradi Federico , Sifalakis Manolis , Van Leekwijck Werner , Latré Steven
Published: June 2021

We propose a spiking neural network (SNN) approach for radar-based hand gesture recognition (HGR), using frequency modulated continuous wave (FMCW) millimeter-wave radar. After pre-processing the range-Doppler or micro-Doppler radar signal, we use a signal-to-spike conversion scheme that encodes radar Doppler maps into spike trains. The spike trains are fed into a spiking recurrent neural network, a liquid state machine (LSM). The readout spike signal from the SNN is then used as input for different classifiers for comparison, including logistic regression, random forest, and support vector machine (SVM). Using liquid state machines of less than 1000 neurons, we achieve better than state-of-the-art results on two publicly available reference datasets, reaching over 98% accuracy on 10-fold cross-validation for both data sets.
The Enlightening Role of Explainable Artificial Intelligence in Chronic Wound Classification
Authors: Sarp Salih , Kuzlu Murat , Wilson Emmanuel , Cali Umit , Guler Ozgur
Published: June 2021

Artificial Intelligence (AI) has been among the most emerging research and industrial application fields, especially in the healthcare domain, but operated as a black-box model with a limited understanding of its inner working over the past decades. AI algorithms are, in large part, built on weights calculated as a result of large matrix multiplications. It is typically hard to interpret and debug the computationally intensive processes. Explainable Artificial Intelligence (XAI) aims to solve black-box and hard-to-debug approaches through the use of various techniques and tools. In this study, XAI techniques are applied to chronic wound classification. The proposed model classifies chronic wounds through the use of transfer learning and fully connected layers. Classified chronic wound images serve as input to the XAI model for an explanation. Interpretable results can help shed new perspectives to clinicians during the diagnostic phase. The proposed method successfully provides chronic wound classification and its associated explanation to extract additional knowledge that can also be interpreted by non-data-science experts, such as medical scientists and physicians. This hybrid approach is shown to aid with the interpretation and understanding of AI decision-making processes.
How Will the Improvements of Electricity Supply Quality in Poor Regions Reduce the Regional Economic Gaps? A Case Study of China
Authors: Zhang Boyan , Wang Mingming
Published: June 2021

Electricity supply quality (ESQ) is critical for healthy economic production, and regional differences in ESQ can widen economic development gaps. To contribute to a more equitable regional development, this study first develops a Gini index of ESQ distribution to measure the inequality among different cities. Then, an econometric model based on the Cobb–Douglas production function is established to quantify the effects of ESQ on regional economy. Finally, we estimate the impacts of ESQ improvement on reducing the economic inequality. The main results show that: (1) Substantial differences exist among the regional ESQ, and the national GDP-based ESQ Gini index was 0.720 in 2018. (2) A GDP-based Lorenz curve has a higher Gini coefficient than the population-based one does, while inequalities in cites are greater than those in rural areas. (3) The ESQ has significant impacts on the regional economic output, and a 1% reduction in the ESQ will, on average, reduce the city-level output by 0.142%. (4) ESQ improvement can significantly narrow the economic gap by up to 24.9%, that is, the ESQ Gini index of GDP distribution will decrease from 0.329 to 0.247 according to our scenario designs.
A Model to Improve the Effectiveness and Energy Consumption to Address the Routing Problem for Cognitive Radio Ad Hoc Networks by Utilizing an Optimized Cuckoo Search Algorithm
Authors: Moila Ramahlapane Lerato , Velempini Mthulisi
Published: June 2021

A cognitive radio ad hoc network (CRAHN) is a mobile network that can communicate without any form of centralized infrastructure. The nodes can learn about the environment and make routing decisions. Furthermore, distributed computing, spectrum mobility, and the Internet of Things have created large data sets, which require more spectrum for data transmission. Unfortunately, the spectrum is a scarce resource that underutilized by licensed users, while unlicensed users are overcrowding the free spectrum. The CRAHNs technology has emerged as a promising solution to the underutilization of the spectrum. The focus of this study is to improve the effectiveness and energy consumption of routing in order to address the routing problem of CRAHNs through the implementation of the optimized cuckoo search algorithm. In CRAHNs, the node and spectrum mobility cause some frequent link breakages within the network, which degrades the performance of the routing protocols. This requires a routing solution to this routing problem. The proposed scheme was implemented in NS2 installed in Linux operating system, with a cognitive radio cognitive network (CRCN) patch. From the experimental results, we observed that the proposed OCS-AODV scheme outperformed CS-DSDV and ACO-AODV schemes. It obtained at least 3.87% packet delivery ratio and 2.56% and lower packets lost. The scheme enabled the mobile nodes to adjust accordingly to minimize energy consumption. If not busy, they switch to an idle state to save battery power.
Boost Voltage Single Phase Full Bridge Inverter with No Voltage Drop Based on Switched Capacitor
Authors: Qiang Hao , Wu Zhenyu , Xu Tian , Kong Pengcheng , Mao Shuren , Zheng Jianfeng
Published: June 2021

In this paper, a voltage-boost-type non-voltage drop single-phase full-bridge inverter connected to a switched-capacitor structure is proposed. The output voltage of the inverter is controlled by the pulse width modulation of a DSP to control the lead and break of the active switches. The full-bridge switches work at low frequency; the other switches work at high frequency. The inverter uses two capacitor modules to charge and discharge alternately so as to overcome the problem of voltage drop on the output side of the inverter in the transition stage from series capacitor discharge to parallel charge. By analyzing the charge–discharge characteristics of the RC charge–discharge circuit, the capacitor charge–discharge cycle can be adjusted to alter the output voltage within a certain range. The results from the physical construction verify the Simulation results achieved well, which demonstrates satisfactory performance that supports the verification of the above theory.
Vibration-Assisted Ball Burnishing
Authors: Jerez-Mesa Ramón , Llumà Jordi , Travieso-Rodríguez J. Antonio
Published: June 2021

Vibration-Assisted Ball Burnishing is a finishing processed based on plastic deformation by means of a preloaded ball on a certain surface that rolls over it following a certain trajectory previously programmed while vibrating vertically. The dynamics of the process are based on the activation of the acoustoplastic effect on the material by means of the vibratory signal transmitted through the material lattice as a consequence of the mentioned oscillation of the ball. Materials processed by VABB show a modified surface in terms of topology distribution and scale, superior if compared to the results of the non-assisted process. Subgrain formation one of the main drivers that explain the change in hardness and residual stress resulting from the process.
Chemical Control of Corythucha arcuata (Say, 1832), an Invasive Alien Species, in Oak Forests
Authors: Bălăcenoiu Flavius , Nețoiu Constantin , Tomescu Romică , Simon Dieter Carol , Buzatu Andrei , Toma Dragoș , Petrițan Ion Cătălin
Published: June 2021

In addition to the classic biotic and abiotic factors that have disrupted the health of forests throughout history, lately, the balance of forest ecosystems has been disturbed by different phenomena such as climate change, pollution, and, especially, biological invasions of invasive alien species. One of the alien species that has invaded Europe relatively quickly is an insect species of North American origin, the oak lace bug (Corythucha arcuata Say, 1832 Heteroptera: Tingidae). In the context of the rapid spread of infestations and the severity of attacks on oak trees in infested forests, this paper aims to assess measures to manage this species in the future. Namely, the effect of aerial chemical treatments on oak lace bug has been investigated with two influencing factors: the mode of insecticide action (contact and systemic) and the treatment volume (low volume and ultra-low volume). The experiment was conducted in two forests over a total area of 350 hectares. The results show that the reduction of the nymph population varied from 91% to 96%. However, the residual population was sufficient to allow differentiated re-infestations over time, more quickly after contact insecticide sprays (22 days after treatment) and slowly after systemic insecticide sprays (more than a month after treatment). This re-infestation time difference had implications on attack intensity as well, with stronger leaf discoloration observed in areas treated with a contact insecticide compared with those treated with a systemic insecticide.
Effects of Several Chemicals on the Migration Behavior of Bursaphelenchus xylophilus (Steiner & Buhrer) Nickle
Authors: Shi Xiu-Feng , Ding Xiao-Lei , Shi Li-Na , Wang Qing-Tong , Ye Jian-Ren
Published: June 2021

The pine wood nematode (PWN), Bursaphelenchus xylophilus, that causes pine wilt disease (PWD), has severely damaged forests and ecosystems in countries of East Asia and Europe. Since the high propagation rate of PWD is the main cause of the devastating disease, it is very important to interfere with the spread of PWN mediated by its insect vector (Monochamus alternatus). In order to explore new methods and approaches for the prevention and control of pine wood nematode disease, chemicals with attraction or repellency to pine wood nematode and stable diffusion or volatilization in infected wood were screened out to interfere and hinder the pupa chamber effect, the aggregation behavior of PWN to pupa chamber in M. alternatus. In the present study, 22 chemicals were inoculated on water agar medium and infected wood to verify the tropism of PWN toward the chemicals from the aspects of attraction and repellency. The results indicate that linoleic acid, oleic acid, diacetyl and β-myrcene have attractive effects on PWN, while kerosene and β-humulene have repellent effects on PWN and are able to stably permeate and volatilize within pine trees. This research shows that some chemicals can affect the movement behavior of PWN and interfere with its migration to the pupal chamber in M. alternatus, thus reducing the dispersal efficiency of PWNs carried by insect vectors. This chemically based strategy would provide novel approaches for effective controlling of pine wilt disease.
Comparison of Variance Estimators for Systematic Environmental Sample Surveys: Considerations for Post-Stratified Estimation
Authors: Frank Bryce , Monleon Vicente J.
Published: June 2021

The estimation of the sampling variance of point estimators under two-dimensional systematic sampling designs remains a challenge, and several alternative variance estimators have been proposed in the past few decades. In this work, we compared six alternative variance estimators under Horvitz-Thompson (HT) and post-stratification (PS) point estimation regimes. We subsampled a multitude of species-specific forest attributes from a large, spatially balanced national forest inventory to compare the variance estimators. A variance estimator that assumes a simple random sampling design exhibited positive relative bias under both HT and PS point estimation regimes ranging between 1.23 to 1.88 and 1.11 to 1.78 for HT and PS, respectively. Alternative estimators reduced this positive bias with relative biases ranging between 1.01 to 1.66 and 0.90 to 1.64 for HT and PS, respectively. The alternative estimators generally obtained improved efficiencies under both HT and PS, with relative efficiency values ranging between 0.68 to 1.28 and 0.68 to 1.39, respectively. We identified two estimators as promising alternatives that provide clear improvements over the simple random sampling estimator for a wide variety of attributes and under HT and PS estimation regimes.
Investigation of Oil Droplet Breakup during Atomization of Emulsions: Comparison of Pressure Swirl and Twin-Fluid Atomizers
Authors: Taboada Martha L. , Zapata Esteban , Karbstein Heike P. , Gaukel Volker
Published: June 2021

The goal of this study was to investigate oil droplet breakup in food emulsions during atomization with pressure swirl (PS), internal mixing (IM), and external mixing (EM) twin-fluid atomizers. By this, new knowledge is provided that facilitates the design of atomization processes, taking into account atomization performance as well as product characteristics (oil droplet size). Atomization experiments were performed in pilot plant scale at liquid volume flow rates of 21.8, 28.0, and 33.3 L/h. Corresponding liquid pressures in the range of 50–200 bar and air-to-liquid ratios in the range of 0.03–0.5 were applied. Two approaches were followed: oil droplet breakup was initially compared for conditions by which the same spray droplet sizes were achieved at constant liquid throughput. For all volume flow rates, the strongest oil droplet breakup was obtained with the PS nozzle, followed by the IM and the EM twin-fluid atomizer. In a second approach, the concept of energy density EV was used to characterize the sizes of resulting spray droplets and of the dispersed oil droplets in the spray. For all nozzles, Sauter mean diameters of spray and oil droplets showed a power-law dependency on EV. PS nozzles achieved the smallest spray droplet sizes and the strongest oil droplet breakup for a constant EV. In twin-fluid atomizers, the nozzle type (IM or EM) has a significant influence on the resulting oil droplet size, even when the resulting spray droplet size is independent of this nozzle type. Overall, it was shown that the proposed concept of EV allows formulating process functions that simplify the design of atomization processes regarding both spray and oil droplet sizes.
Polarimetric Properties of Blazars Caught by the WEBT
Authors: Raiteri Claudia M. , Villata Massimo
Published: June 2021

Active galactic nuclei come in many varieties. A minority of them are radio-loud, and exhibit two opposite prominent plasma jets extending from the proximity of the supermassive black hole up to megaparsec distances. When one of the relativistic jets is oriented closely to the line of sight, its emission is Doppler beamed and these objects show extreme variability properties at all wavelengths. These are called “blazars”. The unpredictable blazar variability, occurring on a continuous range of time-scales, from minutes to years, is most effectively investigated in a multi-wavelength context. Ground-based and space observations together contribute to give us a comprehensive picture of the blazar emission properties from the radio to the γ-ray band. Moreover, in recent years, a lot of effort has been devoted to the observation and analysis of the blazar polarimetric radio and optical behaviour, showing strong variability of both the polarisation degree and angle. The Whole Earth Blazar Telescope (WEBT) Collaboration, involving many tens of astronomers all around the globe, has been monitoring several blazars since 1997. The results of the corresponding data analysis have contributed to the understanding of the blazar phenomenon, particularly stressing the viability of a geometrical interpretation of the blazar variability. We review here the most significant polarimetric results achieved in the WEBT studies.
The Role of Extracellular Vesicles as Shuttles of RNA and Their Clinical Significance as Biomarkers in Hepatocellular Carcinoma
Authors: Costanzi Eva , Simioni Carolina , Varano Gabriele , Brenna Cinzia , Conti Ilaria , Neri Luca Maria
Published: June 2021

Extracellular vesicles (EVs) have attracted interest as mediators of intercellular communication following the discovery that EVs contain RNA molecules, including non-coding RNA (ncRNA). Growing evidence for the enrichment of peculiar RNA species in specific EV subtypes has been demonstrated. ncRNAs, transferred from donor cells to recipient cells, confer to EVs the feature to regulate the expression of genes involved in differentiation, proliferation, apoptosis, and other biological processes. These multiple actions require accuracy in the isolation of RNA content from EVs and the methodologies used play a relevant role. In liver, EVs play a crucial role in regulating cell–cell communications and several pathophysiological events in the heterogeneous liver class of cells via horizontal transfer of their cargo. This review aims to discuss the rising role of EVs and their ncRNAs content in regulating specific aspects of hepatocellular carcinoma development, including tumorigenesis, angiogenesis, and tumor metastasis. We analyze the progress in EV-ncRNAs’ potential clinical applications as important diagnostic and prognostic biomarkers for liver conditions.
Gene Conversion amongst Alu SINE Elements
Authors: Doronina Liliya , Reising Olga , Schmitz Jürgen
Published: June 2021

The process of non-allelic gene conversion acts on homologous sequences during recombination, replacing parts of one with the other to make them uniform. Such concerted evolution is best described as paralogous ribosomal RNA gene unification that serves to preserve the essential house-keeping functions of the converted genes. Transposed elements (TE), especially Alu short interspersed elements (SINE) that have more than a million copies in primate genomes, are a significant source of homologous units and a verified target of gene conversion. The consequences of such a recombination-based process are diverse, including multiplications of functional TE internal binding domains and, for evolutionists, confusing divergent annotations of orthologous transposable elements in related species. We systematically extracted and compared 68,097 Alu insertions in various primates looking for potential events of TE gene conversion and discovered 98 clear cases of Alu–Alu gene conversion, including 64 cases for which the direction of conversion was identified (e.g., AluS conversion to AluY). Gene conversion also does not necessarily affect the entire homologous sequence, and we detected 69 cases of partial gene conversion that resulted in virtual hybrids of two elements. Phylogenetic screening of gene-converted Alus revealed three clear hotspots of the process in the ancestors of Catarrhini, Hominoidea, and gibbons. In general, our systematic screening of orthologous primate loci for gene-converted TEs provides a new strategy and view of a post-integrative process that changes the identities of such elements.
A Guideline of Cross Taping for the Assessment and Treatment of Musculoskeletal Disorder
Authors: Lee Jung-Hoon
Published: June 2021

Recently, the use of cross taping has increased, especially among clinicians in Europe, in the treatment of various musculoskeletal disorders [...]
A Sustainable Viticulture Method Adapted to the Cold Climate Zone in China
Authors: Han Xing , Xue Tingting , Liu Xu , Wang Zhilei , Zhang Liang , Wang Ying , Yao Fei , Wang Hua , Li Hua
Published: June 2021

Due to the particularity of the continental monsoon climate in China, more than 90% of the wine grape cultivation areas require vines to be buried in winter for a burial period that can extend to half a year. Additionally, traditional vine cultivation practices can expose the surface of the soil during winter, easily leading to soil erosion. To meet the restrictive factors for viticulture in the Chinese cold climate zone, a new sustainable viticulture strategy called crawled cordon mode (CCM) has been developed. CCM includes crawled cordon training (CCT), physical methods of flower and fruit thinning, winter suspension of shoots, the use of a biodegradable liquid film, and covering of grass and branches for simplified management of vineyards. This article summarizes the specific implementation methods of the main measures of CCM and their significant effects on the quality of grapes and wine, ecological environment, and costs, and aims to provide inspiration for the study of sustainable and eco-friendly cultivation measures for vineyards in other cold climate zones.
Reality Check 2: The Cost-Effectiveness of Policy Disallowing Body Checking in Non-Elite 13- to 14-Year-Old Ice Hockey Players
Authors: Currie Gillian , Lee Raymond , Palacios-Derflingher Luz , Hagel Brent , Black Amanda , Babul Shelina , Mrazik Martin , Marshall Deborah , Emery Carolyn
Published: June 2021

Sport-related injuries are the leading cause of injury in youth and are costly to the healthcare system. When body checking is disallowed in non-elite levels of Bantam (ages 13–14 years) ice hockey, the injury rate is reduced, however the impact on costs is unknown. This study compared rates of game injuries and costs among non-elite Bantam ice hockey leagues that disallow body checking to those that did not. Methods: An economic evaluation was conducted alongside a prospective cohort study comparing 608 players from leagues where body checking was allowed in games (Calgary/Edmonton 2014–2015, Edmonton 2015–2016) with 396 players from leagues where it was not allowed in games (Vancouver, Kelowna 2014–2015, Calgary in 2015–2016). The effectiveness measure was the rate of game injuries per 1000 player-hours. Costs were estimated based on associated healthcare use within the publicly funded healthcare system as well as privately paid healthcare costs. Probabilistic sensitivity analysis was conducted using bootstrapping. Results: Disallowing body checking reduced the rate of injuries by 3.02 per 1000 player hours (95% CI −4.01, −1.35) and reduced public and total healthcare system costs by $ 1084 (95% CI $ −1716, $ −416) and $ 1100 (95% CI $ −1804, $ −346 per 1000 player-hours, respectively. These findings were robust in over 99% of iterations in sensitivity analyses in the public healthcare and the total healthcare system perspectives. There was no statistically significant difference in privately paid healthcare costs ($ −46 per 1000 player hours (95% CI $ −156, $ 70)). Interpretation: Disallowing body checking in non-elite 13–14-year-old ice hockey nationally would prevent injuries and reduce public healthcare costs.