bluuebunny/crossref_metadata_2025 huggingface dataset:
A Two-Channel High-Performance DC-DC Converter for Mobile AMOLED Display Based on the PWM–SPWM Dual-Mode Switching Method
Authors: Kim Hak-Yun , Kim Tae-Un , Choi Ho-Yong
Published: August 2021

In this paper, we propose a design of a two-channel high-performance DC-DC converter that provides a positive voltage VPOS with a low ripple, and a negative voltage VNEG with high power efficiency, for the purpose of enhancing power efficiency and output ripple under light loads of 100 mA or less for mobile active-matrix organic light-emitting diode (AMOLED) displays. The VPOS was designed as a boost converter using a novel input voltage variation reduction circuit (IVVRC), which rapidly changes the pulse width for input voltage fluctuations, using a feed-forward path. The VNEG was designed as an inverting buck–boost converter based on the pulse width modulation–set time variable pulse width modulation (PWM–SPWM) dual-mode switching method to enhance power efficiency, especially under light loads, and to reduce the overhead of the circuit configuration using a voltage-controlled oscillator. In addition, an adaptive dead-time using voltage detection of switching node (ADTVS) circuit was proposed to enhance power efficiency, which detects the voltage of the switching node at every cycle, and keeps the dead-time constant irrespective of changes in driving conditions. The proposed converter was fabricated with a chip size of 1.67 mm × 2.44 mm, using a 0.35 μm BCD process. Measurement results showed that the power efficiency of our converter was 72.9%~90.4% at 5 mA–100 mA light load output current, which is 2.7%~5.8% higher than the output of the previous converter. Furthermore, the output voltage ripple of VPOS and VNEG at 5 mA light load output current was 3.0 mV and 5.3 mV, respectively, which improved by 19% and 25% as compared to those of the previous converter, respectively.
Prospects of Robots in Assisted Living Environment
Authors: Mahmood Safdar , Ampadu Kwame Owusu , Antonopoulos Konstantinos , Panagiotou Christos , Mendez Sergio Andres Pertuz , Podlubne Ariel , Antonopoulos Christos , Keramidas Georgios , Hübner Michael , Goehringer Diana , Voros Nikolaos
Published: August 2021

From caretaking activities for elderly people to being assistive in healthcare setup, mobile and non-mobile robots have the potential to be highly applicable and serviceable. The ongoing pandemic has shown that human-to-human contact in healthcare institutions and senior homes must be limited. In this scenario, elderlies and immunocompromised individuals must be exclusively protected. Robots are a promising way to overcome this problem in assisted living environments. In addition, the advent of AI and machine learning will pave a way for intelligent robots with cognitive abilities, while enabling them to be more aware of their surroundings. In this paper, we discuss the general perspectives, potential research opportunities, and challenges arising in the area of robots in assisted living environments and present our research work pertaining to certain application scenarios, i.e., robots in rehabilitation and robots in hospital environments and pandemics, which, in turn, exhibits the growing prospects and interdisciplinary nature of the field of robots in assisted living environment.
Design of Wideband Antenna Array with Dielectric Lens and Defected Ground Structure
Authors: Wang Jinhang , Cui Wenjie , Zhou Yang , Liu Ruipeng , Wang Mengjun , Fan Chao , Zheng Hongxing , Li Erping
Published: August 2021

In order to increase the gain of an end-fire antenna array and improve its broadband characteristics, techniques using a dielectric lens and defected ground structure have been investigated in this paper. The element of the array was constructed using an antipodal tapered slot, and two pairs of U-slots were symmetrically cut on the edges of the two antipodal fins to obtain better performance regarding impedance and radiation in the wider band. While loading an ellipse dielectric lens onto each element, the direction and gain were enhanced at the higher frequency. Meanwhile, a defected ground structure was added on the ground plane to decline the mutual coupling of adjacent radiation arms. This design method was verified by a four-element array and a four-way Wilkinson power divider was used as a feed network. Finally, a fabricated sample was tested. Experimental results showed the designed array was available.
Price Volatility Transmission in China’s Hardwood Lumber Imports
Authors: Wang Xiudong , Yin Zhonghua , Wang Ruohan
Published: August 2021

Hardwood lumber is the principal part of the global hardwood timber trade. China has become the largest importer of hardwood lumber in the world. However, China’s hardwood lumber imports are affected by price volatility. Thus, we investigated the price volatility transmission of China’s hardwood lumber imports. We aimed to detect the source, path, and intensity of the volatility transmission in China’s hardwood lumber imports, and reveal the intrinsic interactions between price volatilities. To date, there is little research on the price fluctuations of forest products. This paper provides an empirical analysis on the volatility transmission in China’s forest product imports. We selected four types of major hardwood lumber imports to China; that is, teak (Tectona grandis L.F.), merbau (Merbau), sapele (Entandrophragma), and casla (Terminalia spp.) (The Latin names of tree species are given in parentheses), and used their daily prices from 4 August 2010 to 15 April 2020. The Baba–Engle–Kraft–Kroner (BEKK) multivariate models and dynamic conditional correlation (DCC) models were employed. The empirical results indicate that there is an intrinsic relationship between the price fluctuations in China’s hardwood lumber imports. The volatility transmission chain originates from casla; it is transmitted along the casla→sapele→merbau→teak pathway. The direction of transmission is from lower prices to higher prices. The dynamic conditional correlation of each link in the chain does not exhibit any particular time trend. This suggests that volatility transmission is a crucial price mechanism in China’s hardwood lumber imports. Our findings have important policy implications for hedging timber price risks and designing timber trade policies.
The Importance of Time-Saving as a Factor in Transitioning from Woodfuel to Modern Cooking Energy Services: A Systematic Map
Authors: Petrokofsky Gilian , Harvey William J. , Petrokofsky Leo , Ochieng Caroline Adongo
Published: August 2021

Over half of the world’s population lack access to modern energy cooking services (MECS) and instead rely on locally harvested biomass for fuel. The collection and burning of such biomass for cooking have significant negative social, health, economic and environmental impacts and is a major sustainability challenge. The adverse development impacts from households’ continued dependence on polluting stove-and-fuel combinations are significant. Household Air Pollution (HAP) from biomass fuel use accounts for some 4.3 million premature deaths each year, disproportionately affecting women and children. Fuel harvesting and use represent a significant time burden for women and girls. Time savings can be realized through multiple pathways. Understanding the importance of timesaving as a factor in the adoption of clean cooking is thus important in informing the design of cookstove programs and their marketing approach. The systematic evidence evaluation of drivers of and barriers to adoption of modern energy systems undertaken for the World Bank’s Energy Sector Management Assistance Program (ESMAP) was further analysed to create a systematic map of evidence relating to time-saving attributable to the adoption of modern energy systems by traditional fuel users. The umbrella ESMAP evaluation comprised 160 studies, of which 48 are relevant to the current systematic map. Time-saving was gained from (i) a switch from collection to buying fuel; (ii) urban market utilization; (iii) reducing collected fuel quantity; (iv) reducing the distance to fuel collection sites; (v) and reductions of meal preparation time were found as the key drivers/enablers of cleaner energy adoption across the evidence base. Perceptions and recognition of the time-saving benefits of cleaner fuel adoption across studies were reported to be understood for: (i) fuel efficiency; (ii) fuel collection time; (iii) buying fuelwood; and (iv) better household economics. Relatively few studies report on what the time saved was used for; however, those that do investigate timesaving use found that additional time was used for: (i) additional income generation; (ii) professional development; (iii) more cooking (iv) other domestic activities (e.g., learning to sew); (v) eating out; and (vi) leisure activities. While many studies speculate that time is taken away from education, none state that saved time was used for education, beyond employment opportunities or overarching claims of professional development.
Resilience as a Moving Target: An Evaluation of Last Century Management Strategies in a Dry-Edge Maritime Pine Ecosystem
Authors: Moreno-Fernández Daniel , Zavala Miguel A. , Madrigal-González Jaime , Seijo Francisco
Published: August 2021

Forests are intrinsically coupled to human dynamics, both temporally and spatially. This evolution is conditioned by global changes in climatic conditions (teleconnections) and distant socio-economical processes (telecoupling). The main goal of this study is to describe the teleconnections and telecoupling dynamics that have shaped structure and processes in a dry-edge—highly vulnerable to desertification—Mediterranean pine forest during the last century and to evaluate the contribution of historical management strategies to this coupled human and natural system’s (CHANS) overall resilience. For this study, we collected relevant human and natural system data from a dry edge Pinus pinaster Ait. located forest in Central Spain using a CHANS analytical framework operationalizing telecoupling and teleconnection. A key extractive economic activity in the studied forest was resin tapping, which was the main form of land use from the 1920s to the 1950s. Since the 1950s changes in the Spanish economy linked to the emergence of new resin-producing countries, such as China, led to a sharp decline in resin production. Despite additional human system transformations affecting forest governance (e.g., the Spanish Civil War, the transition to democracy, European integration, etc.) and changes in biophysical conditions linked to climate change (e.g., aridification, CO2 fertilization), the standing stocks of P. pinaster increased during the monitoring period due to sound technical and management planning bolstering overall resilience. These historical management decisions, we argue, successfully reconciled overall resilience goals (defined as the maintenance of forest function beyond and desertification avoidance) with three successive historical forest use challenges: intensive firewood collection by local communities in fragile sandy soils, extensive pastoralism in the forest understory and tradeoffs between resin tapping damaged trees, timber production and tree cover as well as the emerging risks of wildfire and climate change.
Effects of Tree Species and Soil Enzyme Activities on Soil Nutrients in Dryland Plantations
Authors: Li Yage , Han Chun , Sun Shan , Zhao Changming
Published: August 2021

Long-term afforestation strongly changes the soil’s physicochemical and biological properties. However, the underlying mechanism of different tree species driving change in soil nutrients is still unclear in the long-term dryland plantations of the Loess Plateau, China. In this study, samples of surface soil (0–20 cm) and woody litter were collected from five plantations (≥50 years) of Caragana korshinskii, Armeniaca sibirica, Populus hopeiensis, Platycladus orientalis, and Pinus tabulaeformis and a natural grassland, and tested for the carbon, nitrogen, phosphorus, and potassium contents, as well as the soil sucrase (SC), urease (UE), and alkaline phosphorus (ALP) activities. We found that soil nutrients, enzyme activities, and the litter’s chemical properties obviously varied among five tree species. C. korshinskii significantly increased the soil’s TC, organic carbon (OC), total nitrogen (TN), available nitrogen (AN), and available potassium (AK) by 28.42%, 56.08%, 57.41%, 107.25%, and 10.29%, respectively, and also increased the soil’s available phosphorus (AP) by 18.56%; while P. orientalis significantly decreased soil TN (38.89%), TP (30.58%), AP (76.39%), TK (8.25%), and AK (8.33%), and also decreased soil OC (18.01%) and AN (1.09%), compared with those in grassland. The C. korshinskii plantation had higher quality litter and soil enzyme activities than the P. orientalis plantation. Moreover, 62.2% of the total variation in soil nutrients was explained by the litter’s chemical properties and soil enzyme activities, and the litter phosphorus (LP) and soil ALP had a more significant and positive impact on soil nutrients. Therefore, tree species, LP, and soil ALP were key factors driving soil nutrient succession in dryland plantations. The significantly positive nitrogen–phosphorus coupling relationship in the “litter–enzyme–soil” system revealed that the improving nitrogen level promoted the phosphorus cycle of the plantation ecosystem. Our results suggest that leguminous tree species are more suitable for dryland afforestation through the regulation of litter quality and soil enzyme activities.
Color Classification and Texture Recognition System of Solid Wood Panels
Authors: Wang Zhengguang , Zhuang Zilong , Liu Ying , Ding Fenglong , Tang Min
Published: August 2021

Solid wood panels are widely used in the wood flooring and furniture industries, and paneling is an excellent material for indoor decoration. The classification of colors helps to improve the appearance of wood products assembled from multiple panels due to the differences in surface colors of solid wood panels. Traditional wood surface color classification mainly depends on workers’ visual observations, and manual color classification is prone to visual fatigue and quality instability. In order to reduce labor costs of sorting and to improve production efficiency, in this study, we introduced machine vision technology and an unsupervised learning technique. First-order color moments, second-order color moments, and color histogram peaks were selected to extract feature vectors and to realize data dimension reduction. The feature vector set was divided into different clusters by the K-means algorithm to achieve color classification and, thus, the solid wood panels with similar surface color were classified into one category. Furthermore, during twice clustering based on second-order color moment, texture recognition was realized on the basis of color classification. A sample of beech wood was selected as the research object, not only was color classification completed, but texture recognition was also realized. The experimental results verified the effectiveness of the technical proposal.
Carbon and Oxygen Gas Exchange in Woody Debris: The Process and Climate-Related Drivers
Authors: Mukhin Victor A. , Diyarova Daria K. , Gitarskiy Mikhail L. , Zamolodchikov Dmitry G.
Published: August 2021

The carbon-to-oxygen relationship and gas exchange balance, organic carbon to CO2 conversion intensity and efficiency, and their relevance to climate parameters and wood decay fungi were investigated for birch woody debris (WD) in the Mid-Urals mixed pine and birch forests. It was shown that, within the range of temperatures from 10 to 40 °C and relative moisture (RM) of wood of 40% and 70%, aerobic gas exchange was observed in the WD, encompassing the physiologically entwined processes of CO2 emission and O2 uptake. Their volumetric ratio (0.9) confirmed that (1) the WD represents a globally significant CO2 source and appropriate O2 consumer and (2) the oxidative conversion of organic carbon is highly efficient in the WD, with an average ratio of CO2 released to O2 consumed equal to 90%. The balance of carbon-to-oxygen gas exchange and oxidizing conversion efficiency in the WD were not affected by either fungal species tested or by moisture or temperature. However, the intensity of gas exchange was unique for each wood decay fungi, and it could be treated as a climate-reliant parameter driven by temperature (Q10 = 2.0–2.1) and moisture (the latter induced a corresponding trend and value changes in CO2 emission and O2 uptake). Depending on the direction and degree of the change in temperature and moisture, their combined effect on the intensity of gas exchange led to its strengthening or weakening; otherwise, it was stabilized. Aerobic respiration of wood decay Basidiomycetes is an essential prerequisite and the major biotic factor in the WD gas exchange, while moisture and temperature are its climatic controllers only.
Landscape Ecological Risk Assessment Based on LUCC—A Case Study of Chaoyang County, China
Authors: Ji Yuxin , Bai Zhongke , Hui Jiawei
Published: August 2021

The ecological environment is suffering from great human disturbance. Scientific assessment of landscape ecological risks can provide scientific guidance for land use management. This study focused on Chaoyang County in China, used ecological risk assessment methods to characterize the impact of land use/land cover (LUCC) change, and revealed the risk aggregation pattern with the help of spatial autocorrelation analysis. The results showed that ecological risk was increased from 2000 to 2010 but decreased from 2010 to 2018. The ecological risk of the Daling River and Xiaoling River basin was at a relatively high level, and low in the northwest and southeast of the study which covered by forest land. Occupying cultivated land for built-up and large-scale deforestation were two of the main factors to contribute to the increase of ecological risk. The distribution of High-High (HH) and Low-Low (LL) risk agglomeration areas was basically the same as risk levels, but the scope is smaller and more precise. Thus, HH and LH risk agglomeration area should be paid more attention to prevent the adverse impact of adjacent areas. Our study gave a novel perspective to investigate the pattern of ecological risk in order for government managers to identify key risk areas.
Soil Metaproteomics as a Tool for Environmental Monitoring of Minelands
Authors: Trindade Felipe Costa , Gastauer Markus , Ramos Silvio Junio , Caldeira Cecílio Frois , Araújo Josiney Farias de , Oliveira Guilherme , Valadares Rafael Borges da Silva
Published: August 2021

Opencast mining drastically alters the landscape due to complete vegetation suppression and removal of topsoil layers. Precise indicators able to address incremental changes in soil quality are necessary to monitor and evaluate mineland rehabilitation projects. For this purpose, metaproteomics may be a useful tool due to its capacity to shed light on both taxonomic and functional overviews of soil biodiversity, allowing the linkage between proteins found in soil and ecosystem functioning. We investigated bacterial proteins and peptide abundance of three different mineland rehabilitation stages and compared it with a non-rehabilitated site and a native area (evergreen dense forest) in the eastern Amazon. The total amount of identified soil proteins was significantly higher in the rehabilitating and native soils than in the non-rehabilitated site. Regarding soil bacterial composition, the intermediate and advanced sites were shown to be most similar to native soil. Cyanobacteria and Firmicutes phyla are abundant in the early stages of environmental rehabilitation, while Proteobacteria population dominates the later stages. Enzyme abundances and function in the three rehabilitation stages were more similar to those found in the native soil, and the higher accumulation of many hydrolases and oxidoreductases reflects the improvement of soil biological activity in the rehabilitating sites when compared to the non-rehabilitated areas. Moreover, critical ecological processes, such as carbon and nitrogen cycling, seem to return to the soil in short periods after the start of rehabilitation activities (i.e., 4 years). Metaproteomics revealed that the biochemical processes that occur belowground can be followed throughout rehabilitation stages, and the enzymes shown here can be used as targets for environmental monitoring of mineland rehabilitation projects.
A BIM-Based Smart System for Fire Evacuation
Authors: Wehbe Rania , Shahrour Isam
Published: August 2021

Building fires constitute a significant threat that affects property, the environment, and human health. The management of this risk requires an efficient fire evacuation system for buildings’ occupants. Therefore, a smart fire evacuation system that combines building information modeling (BIM) and smart technologies is proposed. The system provides the following capacities: (i) early fire detection; (ii) the evaluation of environmental data; (iii) the identification of the best evacuation path; and (iv) information for occupants about the best evacuation routes. The system was implemented in a research building at Lille University in France. The results show the system’s capacities and benefits, particularly for the identification of the best evacuation paths.
Numerical Solutions for Systems of Fractional and Classical Integro-Differential Equations via Finite Integration Method Based on Shifted Chebyshev Polynomials
Authors: Duangpan Ampol , Boonklurb Ratinan , Juytai Matinee
Published: August 2021

In this paper, the finite integration method and the operational matrix of fractional integration are implemented based on the shifted Chebyshev polynomial. They are utilized to devise two numerical procedures for solving the systems of fractional and classical integro-differential equations. The fractional derivatives are described in the Caputo sense. The devised procedure can be successfully applied to solve the stiff system of ODEs. To demonstrate the efficiency, accuracy and numerical convergence order of these procedures, several experimental examples are given. As a consequence, the numerical computations illustrate that our presented procedures achieve significant improvement in terms of accuracy with less computational cost.
Identification of New Chromosomal Loci Involved in com Genes Expression and Natural Transformation in the Actinobacterial Model Organism Micrococcus luteus
Authors: Torasso Kasem Enzo Joaquin , Angelov Angel , Werner Elisa , Lichev Antoni , Vanderhaeghen Sonja , Liebl Wolfgang
Published: August 2021

Historically, Micrococcus luteus was one of the first organisms used to study natural transformation, one of the main routes of horizontal gene transfer among prokaryotes. However, little is known about the molecular basis of competence development in M. luteus or any other representative of the phylum of high-GC Gram-positive bacteria (Actinobacteria), while this means of genetic exchange has been studied in great detail in Gram-negative and low-GC Gram-positive bacteria (Firmicutes). In order to identify new genetic elements involved in regulation of the comEA-comEC competence operon in M. luteus, we conducted random chemical mutagenesis of a reporter strain expressing lacZ under the control of the comEA-comEC promoter, followed by the screening of dysregulated mutants. Mutants with (i) upregulated com promoter under competence-repressing conditions and (ii) mutants with a repressed com promoter under competence-inducing conditions were isolated. After genotype and phenotype screening, the genomes of several mutant strains were sequenced. A selection of putative com-influencing mutations was reinserted into the genome of the M. luteus reporter strain as markerless single-nucleotide mutations to confirm their effect on com gene expression. This strategy revealed mutations affecting com gene expression at genetic loci different from previously known genes involved in natural transformation. Several of these mutations decreased transformation frequencies by several orders of magnitude, thus indicating significant roles in competence development or DNA acquisition in M. luteus. Among the identified loci, there was a new locus containing genes with similarity to genes of the tad clusters of M. luteus and other bacteria.
Performance Evaluation of SpliceAI for the Prediction of Splicing of NF1 Variants
Authors: Ha Changhee , Kim Jong-Won , Jang Ja-Hyun
Published: August 2021

Neurofibromatosis type 1, characterized by neurofibromas and café-au-lait macules, is one of the most common genetic disorders caused by pathogenic NF1 variants. Because of the high proportion of splicing mutations in NF1, identifying variants that alter splicing may be an essential issue for laboratories. Here, we investigated the sensitivity and specificity of SpliceAI, a recently introduced in silico splicing prediction algorithm in conjunction with other in silico tools. We evaluated 285 NF1 variants identified from 653 patients. The effect on variants on splicing alteration was confirmed by complementary DNA sequencing followed by genomic DNA sequencing. For in silico prediction of splicing effects, we used SpliceAI, MaxEntScan (MES), and Splice Site Finder-like (SSF). The sensitivity and specificity of SpliceAI were 94.5% and 94.3%, respectively, with a cut-off value of Δ Score > 0.22. The area under the curve of SpliceAI was 0.975 (p < 0.0001). Combined analysis of MES/SSF showed a sensitivity of 83.6% and specificity of 82.5%. The concordance rate between SpliceAI and MES/SSF was 84.2%. SpliceAI showed better performance for the prediction of splicing alteration for NF1 variants compared with MES/SSF. As a convenient web-based tool, SpliceAI may be helpful in clinical laboratories conducting DNA-based NF1 sequencing.
Polymerase θ Coordinates Multiple Intrinsic Enzymatic Activities during DNA Repair
Authors: Zahn Karl E. , Jensen Ryan B.
Published: August 2021

The POLQ gene encodes DNA polymerase θ, a 2590 amino acid protein product harboring DNA-dependent ATPase, template-dependent DNA polymerase, dNTP-dependent endonuclease, and 5′–dRP lyase functions. Polymerase θ participates at an essential step of a DNA double-strand break repair pathway able to join 5′-resected substrates by locating and pairing microhomologies present in 3′-overhanging single-stranded tails, cleaving the extraneous 3′-DNA by dNTP-dependent end-processing, before extending the nascent 3′ end from the microhomology annealing site. Metazoans require polymerase θ for full resistance to DNA double-strand break inducing agents but can survive knockout of the POLQ gene. Cancer cells with compromised homologous recombination, or other DNA repair defects, over-utilize end-joining by polymerase θ and often over-express the POLQ gene. This dependency points to polymerase θ as an ideal drug target candidate and multiple drug-development programs are now preparing to enter clinical trials with small-molecule inhibitors. Specific inhibitors of polymerase θ would not only be predicted to treat BRCA-mutant cancers, but could thwart accumulated resistance to current standard-of-care cancer therapies and overcome PARP-inhibitor resistance in patients. This article will discuss synthetic lethal strategies targeting polymerase θ in DNA damage-response-deficient cancers and summarize data, describing molecular structures and enzymatic functions.
Role of Calcium/Calcineurin Signalling in Regulating Intracellular Reactive Oxygen Species Homeostasis in Saccharomyces cerevisiae
Authors: Li Guohui , Fu Wenxuan , Deng Yu , Zhao Yunying
Published: August 2021

The calcium/calcineurin signalling pathway is required for cell survival under various environmental stresses. Using Saccharomyces cerevisiae, we explored the mechanism underlying calcium-regulated homeostasis of intracellular reactive oxygen species (ROS). We found that deletion of acyltransferase Akr1 and C-5 sterol desaturase Erg3 increased the intracellular ROS levels and cell death, and this could be inhibited by the addition of calcium. The hexose transporter Hxt1 and the amino acid permease Agp1 play crucial roles in maintaining intracellular ROS levels, and calcium induced the expression of the HXT1 and AGP1 genes. The cytosolic calcium concentration was decreased in both the akr1Δ and erg3Δ mutants relative to wild-type cells, potentially lowering basal expression of HXT1 and AGP1. Moreover, the calcium/calcineurin signalling pathway also induced the expression of AKR1 and ERG3, indicating that Akr1 and Erg3 might perform functions that help yeast cells to survive under high calcium concentrations. Our results provided mechanistic insight into how calcium regulated intracellular ROS levels in yeast.
Substitutions in SurA and BamA Lead to Reduced Susceptibility to Broad Range Antibiotics in Gonococci
Authors: Bodoev Ivan , Malakhova Maja , Bespyatykh Julia , Bespiatykh Dmitry , Arapidi Georgij , Pobeguts Olga , Zgoda Victor , Shitikov Egor , Ilina Elena
Published: August 2021

There is growing concern about the emergence and spread of multidrug-resistant Neisseria gonorrhoeae. To effectively control antibiotic-resistant bacterial pathogens, it is necessary to develop new antimicrobials and to understand the resistance mechanisms to existing antibiotics. In this study, we discovered the unexpected onset of drug resistance in N. gonorrhoeae caused by amino acid substitutions in the periplasmic chaperone SurA and the β-barrel assembly machinery component BamA. Here, we investigated the i19.05 clinical isolate with mutations in corresponding genes along with reduced susceptibility to penicillin, tetracycline, and azithromycin. The mutant strain NG05 (surAmut bamAmut, and penAmut) was obtained using the pan-susceptible n01.08 clinical isolate as a recipient in the transformation procedure. Comparative proteomic analysis of NG05 and n01.08 strains revealed significantly increased levels of other chaperones, Skp and FkpA, and some transport proteins. Efflux pump inhibition experiments demonstrated that the reduction in sensitivity was achieved due to the activity of efflux pumps. We hypothesize that the described mutations in the surA and bamA genes cause the qualitative and quantitative changes of periplasmic chaperones, which in turn alters the function of synthesized cell envelope proteins.
Epilepsy and BRAF Mutations: Phenotypes, Natural History and Genotype-Phenotype Correlations
Authors: Battaglia Domenica I. , Gambardella Maria Luigia , Veltri Stefania , Contaldo Ilaria , Chillemi Giovanni , Veredice Chiara , Quintiliani Michela , Leoni Chiara , Onesimo Roberta , Verdolotti Tommaso , Radio Francesca Clementina , Martinelli Diego , Trivisano Marina , Specchio Nicola , Dravet Charlotte , Tartaglia Marco , Zampino Giuseppe
Published: August 2021

Objective: Cardiofaciocutaneous syndrome (CFCS) is a rare developmental disorder caused by upregulated signaling through the RAS-mitogen-activated protein kinase (MAPK) pathway, mostly resulting from de novo activating BRAF mutations. Children with CFCS are prone to epilepsy, which is a major life-threatening complication. The aim of our study was to define the natural history of epilepsy in this syndrome and exploring genotype–phenotype correlations. Methods: We performed an observational study, including 34 patients with molecularly confirmed diagnosis (11 males, mean age: 15.8 years). The mean follow-up period was 9.2 years. For all patients, we performed neurological examination, cognitive assessment when possible, neuroimaging, electrophysiological assessment and systematic assessment of epilepsy features. Correlation analyses were performed, taking into account gender, age of seizure onset, EEG features, degree of cognitive deficits, type of mutation, presence of non-epileptic paroxysmal events and neuroimaging features. Results: Epilepsy was documented in 64% of cases, a higher prevalence compared to previous reports. Patients were classified into three groups based on their electroclinical features, long-term outcome and response to therapy. A genotype–phenotype correlation linking the presence/severity of epilepsy to the nature of the structural/functional consequences of mutations was observed, providing a stratification based on genotype to improve the clinical management of these patients.
13q Deletion Syndrome Involving RB1: Characterization of a New Minimal Critical Region for Psychomotor Delay
Authors: Privitera Flavia , Calonaci Arianna , Doddato Gabriella , Papa Filomena Tiziana , Baldassarri Margherita , Pinto Anna Maria , Mari Francesca , Longo Ilaria , Caini Mauro , Galimberti Daniela , Hadjistilianou Theodora , De Francesco Sonia , Renieri Alessandra , Ariani Francesca
Published: August 2021

Retinoblastoma (RB) is an ocular tumor of the pediatric age caused by biallelic inactivation of the RB1 gene (13q14). About 10% of cases are due to gross-sized molecular deletions. The deletions can involve the surrounding genes delineating a contiguous gene syndrome characterized by RB, developmental anomalies, and peculiar facial dysmorphisms. Overlapping deletions previously found by traditional and/or molecular cytogenetic analysis allowed to define some critical regions for intellectual disability (ID) and multiple congenital anomalies, with key candidate genes. In the present study, using array-CGH, we characterized seven new patients with interstitial 13q deletion involving RB1. Among these cases, three patients with medium or large 13q deletions did not present psychomotor delay. This allowed defining a minimal critical region for ID that excludes the previously suggested candidate genes (HTR2A, NUFIP1, PCDH8, and PCDH17). The region contains 36 genes including NBEA, which emerged as the candidate gene associated with developmental delay. In addition, MAB21L1, DCLK1, EXOSC8, and SPART haploinsufficiency might contribute to the observed impaired neurodevelopmental phenotype. In conclusion, this study adds important novelties to the 13q deletion syndrome, although further studies are needed to better characterize the contribution of different genes and to understand how the haploinsufficiency of this region can determine ID.
Srs2 and Pif1 as Model Systems for Understanding Sf1a and Sf1b Helicase Structure and Function
Authors: Meir Aviv , Greene Eric C.
Published: August 2021

Helicases are enzymes that convert the chemical energy stored in ATP into mechanical work, allowing them to move along and manipulate nucleic acids. The helicase superfamily 1 (Sf1) is one of the largest subgroups of helicases and they are required for a range of cellular activities across all domains of life. Sf1 helicases can be further subdivided into two classes called the Sf1a and Sf1b helicases, which move in opposite directions on nucleic acids. The results of this movement can range from the separation of strands within duplex nucleic acids to the physical remodeling or removal of nucleoprotein complexes. Here, we describe the characteristics of the Sf1a helicase Srs2 and the Sf1b helicase Pif1, both from the model organism Saccharomyces cerevisiae, focusing on the roles that they play in homologous recombination, a DNA repair pathway that is necessary for maintaining genome integrity.
Evolution, Expression and Meiotic Behavior of Genes Involved in Chromosome Segregation of Monotremes
Authors: Pajpach Filip , Shearwin-Whyatt Linda , Grützner Frank
Published: August 2021

Chromosome segregation at mitosis and meiosis is a highly dynamic and tightly regulated process that involves a large number of components. Due to the fundamental nature of chromosome segregation, many genes involved in this process are evolutionarily highly conserved, but duplications and functional diversification has occurred in various lineages. In order to better understand the evolution of genes involved in chromosome segregation in mammals, we analyzed some of the key components in the basal mammalian lineage of egg-laying mammals. The chromosome passenger complex is a multiprotein complex central to chromosome segregation during both mitosis and meiosis. It consists of survivin, borealin, inner centromere protein, and Aurora kinase B or C. We confirm the absence of Aurora kinase C in marsupials and show its absence in both platypus and echidna, which supports the current model of the evolution of Aurora kinases. High expression of AURKBC, an ancestor of AURKB and AURKC present in monotremes, suggests that this gene is performing all necessary meiotic functions in monotremes. Other genes of the chromosome passenger complex complex are present and conserved in monotremes, suggesting that their function has been preserved in mammals. Cohesins are another family of genes that are of vital importance for chromosome cohesion and segregation at mitosis and meiosis. Previous work has demonstrated an accumulation and differential loading of structural maintenance of chromosomes 3 (SMC3) on the platypus sex chromosome complex at meiotic prophase I. We investigated if a similar accumulation occurs in the echidna during meiosis I. In contrast to platypus, SMC3 was only found on the synaptonemal complex in echidna. This indicates that the specific distribution of SMC3 on the sex chromosome complex may have evolved specifically in platypus.
Who and Why? Understanding Rural Out-Migration in Uganda
Authors: Tumwesigye Samuel , Hemerijckx Lisa-Marie , Opio Alfonse , Poesen Jean , Vanmaercke Matthias , Twongyirwe Ronald , Van Rompaey Anton
Published: August 2021

Rural–urban migration in developing countries is considered to be a key process for sustainable development in the coming decades. On the one hand, rural–urban migration can contribute to the socioeconomic development of a country. On the other hand, it also leads to labor transfer, brain-drain in rural areas, and overcrowded cities where planning is lagging behind. In order to get a better insight into the mechanisms of rural–urban migration in developing countries, this paper analyzes motivations for rural–urban migration from the perspective of rural households in Uganda. A total of 1015 rural households located in southwestern Uganda were surveyed in 2019. A total of 48 percent of these households reported having at least one out-migrant. By means of logistic regression modeling, the likelihood for rural out-migration was assessed using household- and community-level socioeconomic characteristics as predictors. The results show that most out-migrants are from relatively wealthy households with a higher-than-average education level. Typically, these households are located in villages that are well connected with urban centers. Poor households in remote locations send significantly fewer migrants because of their limited access to migration information and poor transport networks. From these findings, the following policy recommendations are made: Firstly, efforts should be made to extend basic social services, including quality education, towards rural areas. Secondly, in order to reduce socially disruptive long-distance migration and the eventual overcrowding and sprawls of major cities, government investments should be oriented towards the upgrading of secondary towns, which can offer rural out-migrants rewarding employment and business opportunities.
A Segmentation Approach to Identify Underwater Dunes from Digital Bathymetric Models
Authors: Cassol Willian Ney , Daniel Sylvie , Guilbert Éric
Published: August 2021

The recognition of underwater dunes has a central role to ensure safe navigation. Indeed, the presence of these dynamic landforms on the seafloor represents a hazard for navigation, especially in navigation channels, and should be at least highlighted to avoid collision with vessels. This paper proposes a novel method dedicated to the segmentation of these landforms in the fluvio-marine context. Its originality relies on the use of a conceptual model in which dunes are characterized by three salient features, namely the crest line, the stoss trough, and the lee trough. The proposed segmentation implements the conceptual model by considering the DBM (digital bathymetric model) as the seafloor surface from which the dunes shall be segmented. A geomorphometric analysis of the seabed is conducted to identify the salient features of the dunes. It is followed by an OBIA (object-based image analysis) approach aiming to eliminate the pixel-based analysis of the seabed surface, forming objects to better describe the dunes present in the seafloor. To validate the segmentation method, more than 850 dunes were segmented in the fluvio-marine context of the Northern Traverse of the Saint-Lawrence river. A performance rate of nearly 92% of well segmented dunes (i.e., true positive) was achieved.
Age of Initial Submarine Volcanism in the Paleo-Tsushima Basin and Implications for Submarine Volcanism in the Opening Stage of the Japan Sea in Northern Kyushu
Authors: Ninomiya Takashi , Shimoyama Shoichi , Taniguchi Sho , Takahashi Toshihiro , Danhara Tohru , Iwano Hideki
Published: August 2021

The Tsushima Lapilli Tuff, the thickest tuff in the Taishu Group on Tsushima Island, underwent a thermal event after deposition, and has not previously yielded a reliable age because various ages have been reported. This study clarifies the eruption age and thermal history of the Tsushima Lapilli Tuff based on fission-track (FT) and U–Pb dating of zircon grains using laser ablation inductively coupled plasma mass spectrometry (ICP-LA-MS) and evaluates submarine volcanism during deposition of the Taishu Group in the southwestern Japan Sea, as well as volcanism change on Tsushima Island. This study revealed that thermal events caused rejuvenation in some single-grain FT ages after deposition in the Tsushima Group, and that the eruption age of the Tsushima Lapilli Tuff was 16.2 ± 0.7 Ma; the age of the largest submarine volcanism event in the Taishu Group in Tsushima Island was thus determined. On the basis of our previous studies, this age and tectonism strongly indicate that felsic submarine volcanism occurred between 18 and 16 Ma, accompanied by rapid subsidence, and the volcanism changed from felsic volcanism originating from melting of old continental crust by asthenospheric upwelling to mafic volcanism originating from small-scale lithospheric mantle upwelling from 13.6 Ma onward.
Advances in Hazelnut (Corylus avellana L.) Rootstocks Worldwide
Authors: Rovira Mercè
Published: August 2021

Studies on hazelnut (Corylus avellana L.) rootstocks have been limited to date. However, the use of vigorous, non-suckering rootstocks for this species could increase the cost-effectiveness of orchards by reducing the annual need to prune suckers, thus facilitating mechanical harvesting, and reducing orchard management costs and environmental impact. Seedlings of the non-suckering Turkish tree hazel (C. colurna L.) have been used traditionally in Serbia. In the 1970s, the United States Department of Agriculture in Corvallis, Oregon (USA) released the first two non-suckering clonal rootstocks—‘Dundee’ and ‘Newberg’—from open-pollinated seeds of C. colurna. Moreover, selection of C. avellana cvs. with few suckers is continuing. Trials carried out in different countries with own-rooted and grafted plants have shown good performance of grafted hazelnuts. Currently, some nurseries in several countries are propagating hazelnut rootstocks and grafting trees for planting commercial orchards. Interest in these cultivar/rootstock combinations is increasing, and more new orchards of grafted trees are expected to be planted in the coming years.
Sextech Use as a Potential Mental Health Reprieve: The Role of Anxiety, Depression, and Loneliness in Seeking Sex Online
Authors: Marcotte Alexandra S. , Kaufman Ellen M. , Campbell Jessica T. , Reynolds Tania A. , Garcia Justin R. , Gesselman Amanda N.
Published: August 2021

Depression, anxiety, and loneliness have long been recognized as global mental health concerns. To temporarily relieve psychological distress, self-soothing behavior is common, including engagement in sexual behaviors that are linked to positive mental well-being. Considering the COVID-19 pandemic further exacerbated many mental health ailments alongside physical distancing regulations, we specifically examined online sexual behavior via the use of emergent digital sexual technologies, or sextech. In a 2019 study of 8004 American adults, we assessed whether people experiencing higher anxiety, depression, and/or loneliness were more likely to engage in sextech use. Furthermore, we examined whether anxiety or depression mediated the association between loneliness and sextech use, as loneliness is one contributor to anxiety and depression. People with higher anxiety and depression were more likely to engage in sextech. However, those who were more lonely were less likely to engage with sextech, suggesting the aforementioned patterns were not due to lack of social connection. Our findings suggest people with mental health struggles may be drawn to interactive, digital forms of sexual behavior as a means of alleviating symptoms through distraction or self-soothing. This insight offers an important pathway for expanding the scope of mental health interventions, particularly as technology becomes increasingly prevalent and accessible in everyday life.
Do Registered Dietitians, Nutrition Students, and Laypeople Perceive Individuals with Obesity Differently?
Authors: Cassiano Giovana Santarosa , Carvalho-Ferreira Joana Pereira , Buckland Nicola J. , da Cunha Diogo Thimoteo
Published: August 2021

(1) Background: Obesity is associated with significant social consequences, and individuals with obesity are regularly affected by weight-related stigmatization experiences. This study compares antifat attitudes among registered dietitians (RD), nutrition students, and laypeople and assesses which factors related to the perceived causes of obesity influence these attitudes. (2) Methods: An online survey was conducted in Brazil with RD (n = 336), nutrition students (n = 300), and laypeople (n = 403) with questionnaires assessing antifat attitudes and perceived causes of obesity. (3) Results: All groups presented low antifat attitudes. Minor differences in antifat attitudes were found among the three groups. Compared to RDs and nutrition students, laypeople presented higher Weight Control/Blame scores, but with a small effect size (η2 = 0.01). Weight bias was predicted by age, sex, and body mass index. External, social, and financial factors were not perceived to be very important in the development of obesity by RD and students. (4) Conclusions: Since slight differences were seen among RD and students compared to laypeople, and some perceptions of the causes of obesity indicate a stigmatized view. It is essential to place a greater focus on educating and updating these health professionals and students about weight stigma and its consequences for the mental and physical health of individuals.
Innovative Culture and Firm Performance of Medical Device Companies: Mediating Effects of Investment in Education and Training
Authors: Ryu Jeong-min , Park Sewon , Park Yoonseo , Park Jeongwon , Lee Munjae
Published: August 2021

This research explored the mediating effect of investment in education and training relating to the innovative culture and organizational performance of medical device companies. We used the Human Capital Corporate Panel data provided by the Korea Vocational Competency Development Institute. In the industrial classification system of panel data, the industries related to medical devices were extracted and conclusively analyzed for 8629 workers and 368 companies. The independent and dependent variables were innovative culture and corporation performance, respectively. Investment in training and education was a mediating variable between the independent and dependent variables. Quantitative data were analyzed using SPSS software. A higher level of organizational satisfaction emerged in an innovative culture. Innovative culture positively affected organizational satisfaction. Further, investment in education and training to promote an innovative culture positively affected organizational satisfaction. Medical device companies should improve their performance by creating an innovative culture.