bluuebunny/crossref_metadata_2025 huggingface dataset:
Imaging Low-Energy Ion Outflow in the Auroral Zone
Authors: Rowland Douglas , Collier Michael , Keller John , Pfaff Robert , Klenzing Jeffrey , McLain Jason , Clemmons James , Hecht James
Published: May 2022

The VISualizing Ion Outflow via Neutral atom imaging during a Substorm (VISIONS) sounding rocket mission investigated the factors leading to ion outflow following a geomagnetic substorm. In situ and remote sensing instrumentation provided complementary measurements that have been combined to yield an in-depth look at the phenomena associated with ion outflow. In particular, the inclusion of instrumentation that provided high spatial and temporal resolution “images” of low-energy neutral atom (ENA) emissions from the nightside auroral zone following a substorm has led to new insights. The observed ENAs were spatially structured, and strongly associated with regions of intense 630.0 nm auroral emissions. The ENAs in the auroral zone were predominantly up-going, consistent with thick-target scattering in the region where the ENA mean free path is close to or less than the atmospheric scale height.
Hypercalcemia and Neurological Symptoms: A Rare Presentation of Hyperfunctioning Parathyroid Adenoma in an Adolescent
Authors: Calcaterra Valeria , Pelizzo Gloria , Pipolo Andreana , Montecamozzo Giulio , Fabiano Valentina , Grazi Roberta , Carlucci Patrizia , Zuccotti Gianvincenzo
Published: May 2022

Neuropsychiatric symptoms are rarely described as a manifestation of hyperparathyroidism, especially in children. We describe the case of an adolescent with hypercalcemia related to and hyperfunctioning parathyroid adenoma presenting with acute neuropsychiatric symptoms. A 14-year-old-girl presented into the Emergency Service Department because of an acute onset of marked asthenia, muscle weakness with difficulty in walking, and altered mental status, which included nonsensical speech. No other neurological signs were present. Abdominal, cardiac, and thoracic examination were unremarkable. There was no recent history of trauma or infection. Family history was negative for neurologic disorders. Her past medical history was unremarkable. A head CT scan showed negative results. The laboratory work-up showed elevated levels of calcium level (14.35 mg/dl; nv 9–11 mg/dl), parathyroid hormone (PTH; 184 pg/ml; nv 3.5–36.8 pg/ml), and creatinine (1.23 mg/dl; nv 0.45–0.75 mg/dl). Sodium, potassium, chloride, thyroid function, glycemia, and insulin values were normal. Neck ultrasonography showed a solid, oval, capsulated, hypoechoic neoformation, with discrete vascularization localized to the inferior pole of the right thyroid lobe, referring to parathyroid tissue. Scintigraphy revealed a hyperfunctioning parathyroid tissue at the inferior pole of the right thyroid lobe. Massive intravenous hydration and diuretic therapy were started. The signs and symptoms of hypercalcemia improved after the initiation of therapy. The patient was submitted to right cervicotomy and muscle sparing for the removal of the adenoma of the right superior parathyroid gland. After surgery, a decrease in PTH levels (<4 pg/ml) and calcium levels (9.1 mg/dl) was recorded. During follow-up, calcium values remained stable; a progressive normalization of PTH was obtained. The oral calcium therapy was suspended after 3 months from surgery. No neuropsychiatric symptoms recurred. An evaluation of the serum calcium level is mandatory in children and adolescents with unexplained neurological signs or symptoms, and a check for hyperparathyroidism should be considered.
Serotyping and Seroprevalence of Mannheimia haemolytica, Pasteurella multocida, and Bibersteinia trehalosi and Assessment of Determinants of Ovine Pasteurellosis in West Amhara Sub-region, Ethiopia
Authors: Getnet Kalkidan , Abera Bezawit , Getie Haymanot , Molla Wassie , Mekonnen Sefinew Alemu , Megistu Bemrew Admassu , Abat Anmaw Shite , Dejene Haileyesus , Birhan Mastewal , Ibrahim Saddam Mohammed
Published: May 2022

A cross-sectional study was undertaken in four (4) districts of the West Amhara sub-region of Ethiopia with the aim of assessing the diversity and distribution of serotypes of Pasteurella species, their seroprevalence, and associated risk factors, and knowledge, attitude, and practice of farmers toward ovine pasteurellosis. A total of 600 sheep sera were collected using multistage cluster sampling. Each sample was examined for the presence of six (6) serotype-specific antibodies using an indirect haemagglutination test. We are reporting a higher seroprevalence of 90.17% (541/600) in which all seropositive animals were shown to have been co-infected with multiple serotypes. Individual serotype prevalence showed that serotype A7 has the highest prevalence of 77.83% followed by A2 (74.33%), T15 (64%), T4 (62%), PA (60%), and A1 (39.17%). In this study, being female [odds ratio (OR): 2.45, 95% CI (1.09–5.52), p = 0.031] and living in high altitude areas [OR: 20.29, 95% CI (2.54–161.95), p = 0.004] were found to be significantly associated with sero-positivity. A questionnaire survey (n = 384) employed in a face-to-face interview was used to assess the knowledge, attitude, and practice of farmers related to ovine pasteurellosis. Accordingly, the majority (72.4%) of respondents had an inadequate knowledge level of the disease. The proportion of farmers with a favorable attitude and good practices toward the disease was 50.26 and 77.6%, respectively. This study is highly indicative that ovine pasteurellosis is a ubiquitous disease in the study area challenging the sheep production sector. The existence of diverse serotypes reported to lack cross-protective immunity is likely to explain why the current vaccination practice with the mono-serotype Pasteurella multocida biotype A vaccine is not providing adequate protection against outbreaks of the disease. Prioritization of one or more serotypes for inclusion in a multivalent vaccine should be dictated by the abundance and distribution of a particular serotype, its clinical importance, and its resultant economic impact. Furthermore, training farmers on key aspects of the disease is vital in the implementation of effective disease management strategies through a participatory approach. Data from the remaining regions of the country could help realize the development of an effective vaccine that works best at the national level.
Research Progress on the Theory and Practice of Grassland Eco-Compensation in China
Authors: Li Zhidong , Su Boru , Liu Moucheng
Published: May 2022

In order to curb the phenomenon of grassland degradation caused by human activity, China has begun the exploration of grassland eco-compensation, setting an example for the ecological protection of grasslands and sustainable use of resources around the world. At this stage, China has invested more than 170 billion yuan in grassland eco-compensation, benefiting 12 million farmer and herder households. The related research involves various perspectives, scopes, and methods, but lacks systematic reviewing. This study reviews the relevant theoretical and practical research and explores the connotations and effects of grassland eco-compensation in China. In general, the current grassland eco-compensation in China is a large-scale ecological-economic institutional arrangement with the following five characteristics: (1) the goals are to maintain the grassland ecosystem services and increase the income of herder households; (2) the main bodies are governments and herder households; (3) the main method is financial transfer payments; (4) the compensation standards are based on the opportunity costs of the herder households’ responses as the lower limits and the grassland ecosystem service values as the upper limits; and (5) it is a comprehensive compensation system that requires legal, regulatory, technological support and long-term mechanisms. Since 2011, driven by the grassland eco-compensation policy, the income levels of herder households in each pilot area have generally increased, and the overall ecology of grasslands has slightly improved. However, there are still some areas where overload is common. Additionally, there are regional differences in the satisfaction degree of herder households, which is mainly affected by factors such as family income, compensation cognition and family holding grassland scale. Our analysis shows that the shortcomings of current theoretical research are mainly reflected in the low precision of scientific compensation standards, the lack of a basis for differentiated standards, and the single compensation method. The shortcoming of practical research is that most effect evaluations cannot reflect the role of eco-compensation in it. This study suggests that future work should focus on the response mechanism of herder households and the improvement of the compensation measures. At the same time, the scope of research should be expanded, and we should learn from advanced compensation experience in other fields.
Plastic Pollution in Soil and Crops: Effects of Film Residuals on Soil Water Content and Tomato Physiology
Authors: Li Zhuoran , Ma Juanjuan , Sun Xihuan , Guo Xianghong , Zheng Lijian , Chen Jinping
Published: May 2022

Agricultural producers in China are presently confronting the challenge of “white pollution” caused by the continuous expansion of plastic film area coverage. The main objective of this research is to address the increasing interest in the effects of film residual on tomato growth, yield, and quality under drip irrigation. To reveal the effects of film residual on tomato physiology, field trials were conducted with five levels of film residual treatment applied in two consecutive cropping seasons from 2019 to 2020. Soil water content, plant height, stem diameter, photosynthetic characteristics, yield, soluble sugar content (SSC), organic acid (OA), vitamin C (VC), and nitrate content (NC) were measured; furthermore, four analysis methods were used to assess the comprehensive tomato quality. The results showed that film residuals significantly affected soil water content in 2019 and 2020 and inhibited tomato plant height and stem diameter. The variations in photosynthetic rate and stomatal conductance showed practically the same trend, increasing with an increase in the film residual at the seedling stage. The maximum yields were observed at 94.02 ton/hm2 and 84.44 ton/hm2 in 2019 and 2020, respectively, and tomato yield exhibited a shape reduction with increasing amounts of film residual in all years. SSC, VC, and NC showed an increasing trend with increasing amounts of film residual. The best tomato comprehensive quality was observed when the amount of film residual was lower than 200 kg/hm2 and declined with an increasing amount of film residual. Overall, the soil water content, tomato growth, and fruit quality changed significantly under the influence of film residual. These results not only deepen our understanding of the harm caused by film residual to tomato growth and fruit quality but also provide reasonable advice to establish a management system for residual pollution on cultivated land.
Germination and Growth Performance of Water-Saving and Drought-Resistant Rice Enhanced by Seed Treatment with Wood Vinegar and Biochar under Dry Direct-Seeded System
Authors: Zhang Kangkang , Khan Zaid , Liu Jiahuan , Luo Tao , Zhu Kunmiao , Hu Liyong , Bi Junguo , Luo Lijun
Published: May 2022

Dry direct-seeded rice (dry-DSR) is an efficient, resource-saving and environmentally friendly cropping system. The employment of water-saving and drought-resistant rice (WDR) for dry direct-seeding can better meet the needs of dry-direct seeding systems. However, the decline in seedling emergence rate and poor seedling growth are the main bottlenecks under current direct-seeded rice production. Seed treatment is a sustainable and effective technique to overcome these issues. Therefore, growth chamber and field experiments were conducted to assess the impact of poplar wood vinegar (WV) priming and rice straw biochar (BC) coating on emergence, establishment, growth, physio-biochemical events, and ultimate yield. We treated the seeds of WDR viz., Hanyou 73 with WV, BC, and co-treatment WV + BC. The results showed that seed priming with 1:50 WV concentration and coating with 20% BC content was the optimal ratio for promoting germination and seedling growth. The field evaluation indicated that individual WV and BC markedly promoted the final emergence by 58% and 31%, respectively, while co-treatment WV + BC increased by 67%. Likewise, WV and BC significantly enhanced total seedling biomass by 26% and 10%, respectively, and the respective enhancement of WV + BC was 31%. For ultimate yield, WV and BC produced 12% and 19% higher grain yield, respectively, whereas WV + BC yielded 20%. The above results revealed that WV and WV + BC were the most effective treatment. Our findings may provide new avenues for advancing pre-sowing seed treatments facilitating the stand establishment and grain yield of dry direct-seeded rice.
Cellular Prion Protein Expression in the Brain Tissue from Brucella ceti-Infected Striped Dolphins (Stenella coeruleoalba)
Authors: Angelucci Clotilde Beatrice , Giacominelli-Stuffler Roberto , Baffoni Marina , Di Francesco Cristina Esmeralda , Di Francesco Gabriella , Di Renzo Ludovica , Tittarelli Manuela , Petrella Antonio , Grattarola Carla , Mazzariol Sandro , Sierra Eva , Fernández Antonio , Di Guardo Giovanni
Published: May 2022

Brucella ceti, a zoonotic pathogen of major concern to cetacean health and conservation, is responsible for severe meningo-encephalitic/myelitic lesions in striped dolphins (Stenella coeruleoalba), often leading to their stranding and death. This study investigated, for the first time, the cellular prion protein (PrPc) expression in the brain tissue from B. ceti-infected, neurobrucellosis-affected striped dolphins. Seven B. ceti-infected, neurobrucellosis-affected striped dolphins, found stranded along the Italian coastline (6) and in the Canary Islands (1), were investigated, along with five B. ceti-uninfected striped dolphins from the coast of Italy, carrying no brain lesions, which served as negative controls. Western Blot (WB) and immunohistochemistry (IHC) with an anti-PrP murine monoclonal antibody were carried out on the brain parenchyma of these dolphins. While PrPc IHC yielded inconclusive results, a clear-cut PrPc expression of different intensity was found by means of WB analyses in the brain tissue of all the seven herein investigated, B. ceti-infected and neurobrucellosis-affected cetacean specimens, with two dolphins stranded along the Italian coastline and one dolphin beached in Canary Islands also exhibiting a statistically significant increase in cerebral PrPc expression as compared to the five Brucella spp.-negative control specimens. The significantly increased PrPc expression found in three out of seven B. ceti-infected, neurobrucellosis-affected striped dolphins does not allow us to draw any firm conclusion(s) about the putative role of PrPc as a host cell receptor for B. ceti. Should this be the case, an upregulation of PrPc mRNA in the brain tissue of neurobrucellosis-affected striped dolphins could be hypothesized during the different stages of B. ceti infection, as previously shown in murine bone marrow cells challenged with Escherichia coli. Noteworthy, the inflammatory infiltrates seen in the brain and in the cervico-thoracic spinal cord segments from the herein investigated, B. ceti-infected and neurobrucellosis-affected striped dolphins were densely populated by macrophage/histiocyte cells, often harboring Brucella spp. antigen in their cytoplasm, similarly to what was reported in macrophages from mice experimentally challenged with B. abortus. Notwithstanding the above, much more work is needed in order to properly assess the role of PrPc, if any, as a host cell receptor for B. ceti in striped dolphins.
Epidemiology of Plasmids in Escherichia coli and Klebsiella pneumoniae with Acquired Extended Spectrum Beta-Lactamase Genes Isolated from Chronic Wounds in Ghana
Authors: Pankok Frederik , Taudien Stefan , Dekker Denise , Thye Thorsten , Oppong Kwabena , Wiafe Akenten Charity , Lamshöft Maike , Jaeger Anna , Kaase Martin , Scheithauer Simone , Tanida Konstantin , Frickmann Hagen , May Jürgen , Loderstädt Ulrike
Published: May 2022

Little information is available on the local epidemiology of mobile genetic elements such as plasmids harboring acquired beta-lactamase genes in Western African Ghana. In the present study, we screened for plasmids in three Escherichia coli and four Klebsiella pneumoniae isolates expressing extended spectrum beta-lactamases (ESBL) mediated by the blaCTX-M-15 gene from chronically infected wounds of Ghanaian patients. Bacterial isolates were subjected to combined short-read and long-read sequencing to obtain the sequences of their respective plasmids. In the blaCTX-M-15-gene-carrying plasmids of the four ESBL-positive K. pneumoniae isolates, IncFIB/IncFII (n = 3) and FIA (n = 1) sequences were detected, while in the blaCTX-M-15-gene-carrying plasmids of the three ESBL-positive E. coli isolates, IncFIA/IncFIB (n = 2) and IncFIB (n = 1) sequences were found. The three IncFIB/IncFII sequence-containing plasmids were almost identical to a K. pneumoniae plasmid reported from France. They belonged to the clonal lineages ST17, ST36 and ST39 of K. pneumoniae, suggesting transversal spread of this obviously evolutionary successful plasmid in Ghana. Other resistance gene-encoding plasmids observed in the assessed Enterobacterales harbored IncFIA/IncR and IncFII sequences. International spread was confirmed by the high genetic similarity to resistance-mediating plasmids published from Asia, Australia, Europe and Northern America, including a blaCTX-M-15-gene-carrying plasmid isolated from a wild bird in Germany. In conclusion, the study contributed to the scarcely available information on the epidemiology of third-generation cephalosporine resistance-mediating plasmids in Ghana. Furthermore, the global spread of resistance-mediating plasmids provided hints on the evolutionary success of individual resistance-harboring plasmids by transversal spread among K. pneumoniae lineages in Ghana.
Modulating the Growth, Antioxidant Activity, and Immunoexpression of Proinflammatory Cytokines and Apoptotic Proteins in Broiler Chickens by Adding Dietary Spirulina platensis Phycocyanin
Authors: Omar Anaam E. , Al-Khalaifah Hanan S. , Osman Ali , Gouda Ahmed , Shalaby Shimaa I. , Roushdy Elshimaa M. , Abdo Samar A. , Ali Sozan A. , Hassan Aziza M. , Amer Shimaa A.
Published: May 2022

This study investigated the dietary effect of Spirulina platensis phycocyanin (SPC) on growth performance (body weight (BW), body weight gain (BWG), feed intake (FI), feed conversion ratio (FCR)) at starter, grower, and finisher stages, intestinal histomorphology, serum biochemical parameters, inflammatory and antioxidant indices, and proinflammatory cytokines (tumor necrosis factor-α and caspase-3) immune expression in broiler chickens. In total, 250 one-day-old chicks (Ross 308 broiler) were randomly allotted to five experimental groups (5 replicates/group, 10 chicks/replicate) and fed basal diets supplemented with five levels of SPC (0, 0.25, 0.5, 0.75, and 1 g kg–1 diet) for 35 days. Compared with SPC0 treatment, different SPC levels increased the overall BW and BWG without affecting the total feed consumption. However, the FCR decreased linearly with an increase in supplementation level. The serum levels of total proteins, albumin, globulins, and growth hormone increased linearly by increasing levels of SPC supplementation. Further, SPC supplementation increased the thyroxin hormones without affecting serum glucose and leptin levels. Serum total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) values decreased in broilers fed SPC0.250 and SPC1 diets. Triglycerides (TG) decreased in SPC0.25-, SPC0.75-, and SPC1-treated groups. Though antioxidant enzyme activities (total antioxidant capacity, catalase, and superoxide dismutase) increased linearly and quadratically, malondialdehyde (MDA) decreased linearly by increasing the SPC level. There was no effect on serum proinflammatory cytokines IL1β levels. Immunolabelling index of caspase-3 and tumor necrosis factor-α (TNF-α) were downregulated by SPC supplementation. The intestinal histomorphology is represented by increased villus height, the villus height to crypt depth ratio, and numbers of goblet cells in different sections of the small intestine. In conclusion, SPC supplementation is beneficial in broiler chicken diets due to its growth-promoting, antioxidant, and anti-inflammatory properties.
Redox Mechanisms of Platelet Activation in Aging
Authors: Gu Sean X. , Dayal Sanjana
Published: May 2022

Aging is intrinsically linked with physiologic decline and is a major risk factor for a broad range of diseases. The deleterious effects of advancing age on the vascular system are evidenced by the high incidence and prevalence of cardiovascular disease in the elderly. Reactive oxygen species are critical mediators of normal vascular physiology and have been shown to gradually increase in the vasculature with age. There is a growing appreciation for the complexity of oxidant and antioxidant systems at the cellular and molecular levels, and accumulating evidence indicates a causal association between oxidative stress and age-related vascular disease. Herein, we review the current understanding of mechanistic links between oxidative stress and thrombotic vascular disease and the changes that occur with aging. While several vascular cells are key contributors, we focus on oxidative changes that occur in platelets and their mediation in disease progression. Additionally, we discuss the impact of comorbid conditions (i.e., diabetes, atherosclerosis, obesity, cancer, etc.) that have been associated with platelet redox dysregulation and vascular disease pathogenesis. As we continue to unravel the fundamental redox mechanisms of the vascular system, we will be able to develop more targeted therapeutic strategies for the prevention and management of age-associated vascular disease.
Physiological Overview of the Potential Link between the UPS and Ca2+ Signaling
Authors: Lee Dongun , Hong Jeong Hee
Published: May 2022

The ubiquitin–proteasome system (UPS) is the main proteolytic pathway by which damaged target proteins are degraded after ubiquitination and the recruit of ubiquitinated proteins, thus regulating diverse physiological functions and the maintenance in various tissues and cells. Ca2+ signaling is raised by oxidative or ER stress. Although the basic function of the UPS has been extensively elucidated and has been continued to define its mechanism, the precise relationship between the UPS and Ca2+ signaling remains unclear. In the present review, we describe the relationship between the UPS and Ca2+ signaling, including Ca2+-associated proteins, to understand the end point of oxidative stress. The UPS modulates Ca2+ signaling via the degradation of Ca2+-related proteins, including Ca2+ channels and transporters. Conversely, the modulation of UPS is driven by increases in the intracellular Ca2+ concentration. The multifaceted relationship between the UPS and Ca2+ plays critical roles in different tissue systems. Thus, we highlight the potential crosstalk between the UPS and Ca2+ signaling by providing an overview of the UPS in different organ systems and illuminating the relationship between the UPS and autophagy.
Microwave-Assisted Dendropanax morbifera Extract for Cosmetic Applications
Authors: Hoang Hien Thi , Park Jae-Seok , Kim Seong-Hyeon , Moon Ju-Young , Lee Young-Chul
Published: May 2022

Recently, utilizing natural bioactive compounds for active ingredients in cosmetics has become a growing worldwide trend. More and more studies aim to identify the sources of herbal ingredients for applications in the pharmaceutical and cosmetic fields. Additionally, in order to optimize the safety of natural ingredients, choosing an environmentally friendly extraction method also plays an important role. In this work, an eco-friendly extraction technique for Dendropanax morbifera using microwave treatment and microwave-assisted Dendropanax morbifera extract (MA-DME) was investigated. The results indicate that higher yields of MA-DME were obtained than with conventional methods and that D. morbifera’s antioxidant properties were enhanced. Moreover, we found that MA-DME exhibited extraordinary antioxidant, anti-aging, and skin-whitening activities. We suggest MA-DME as a potential cosmeceutical ingredient than could be utilized for comprehensive protection of human skin.
Thioredoxin Reductase-Type Ferredoxin: NADP+ Oxidoreductase of Rhodopseudomonas palustris: Potentiometric Characteristics and Reactions with Nonphysiological Oxidants
Authors: Lesanavičius Mindaugas , Seo Daisuke , Čėnas Narimantas
Published: May 2022

Rhodopseudomonas palustris ferredoxin:NADP+ oxidoreductase (RpFNR) belongs to a novel group of thioredoxin reductase-type FNRs with partly characterized redox properties. Based on the reactions of RpFNR with the 3-acetylpyridine adenine dinucleotide phosphate redox couple, we estimated the two-electron reduction midpoint potential of the FAD cofactor to be −0.285 V. 5-Deaza-FMN-sensitized photoreduction revealed −0.017 V separation of the redox potentials between the first and second electron transfer events. We examined the mechanism of oxidation of RpFNR by several different groups of nonphysiological electron acceptors. The kcat/Km values of quinones and aromatic N-oxides toward RpFNR increase with their single-electron reduction midpoint potential. The lower reactivity, mirroring their lower electron self-exchange rate, is also seen to have a similar trend for nitroaromatic compounds. A mixed single- and two-electron reduction was characteristic of quinones, with single-electron reduction accounting for 54% of the electron flux, whereas nitroaromatics were reduced exclusively via single-electron reduction. It is highly possible that the FADH· to FAD oxidation reaction is the rate-limiting step during the reoxidation of reduced FAD. The calculated electron transfer distances in the reaction with quinones and nitroaromatics were close to those of Anabaena and Plasmodium falciparum FNRs, thus demonstrating their similar “intrinsic” reactivity.
Oxidation of Polyunsaturated Fatty Acids as a Promising Area of Research in Infertility
Authors: Collodel Giulia , Moretti Elena , Noto Daria , Corsaro Roberta , Signorini Cinzia
Published: May 2022

In this review, the role of fatty acids (FA) in human pathological conditions, infertility in particular, was considered. FA and FA-derived metabolites modulate cell membrane composition, membrane lipid microdomains and cell signaling. Moreover, such molecules are involved in cell death, immunological responses and inflammatory processes. Human health and several pathological conditions are specifically associated with both dietary and cell membrane lipid profiles. The role of FA metabolism in human sperm and spermatogenesis has recently been investigated. Cumulative findings indicate F2 isoprostanes (oxygenated products from arachidonic acid metabolism) and resolvins (lipid mediators of resolution of inflammation) as promising biomarkers for the evaluation of semen and follicular fluid quality. Advanced knowledge in this field could lead to new scenarios in the treatment of infertility.
Reinforcement Design of the Support Frame of a Petrochemical Heater
Authors: Yeh Chun-Lang
Published: May 2022

In this paper, we investigated the operating security of the support frame of a petrochemical heater under the action of a strong wind. When the fatigue limit was exceeded, the support frame was damaged. We monitored the heater before reinforcement and then applied the finite element method to analyze and compare nine different kinds of reinforcement methods for the support frame. From the results of the finite element analysis, fatigue failure of the support frame before reinforcement occurred at locations where the computed stresses from the finite element analysis were large, thus partially justifying the adequacies of the present analysis methods and results. Among the nine reinforcement methods, we suggest case 9 to reinforce a support frame so that its operating security under the action of a strong wind can be improved. At the end of this paper, several future studies are suggested, including verification of the reinforcement for the support frame and the establishment of the system for automatic stress monitoring and analysis.
GaN-on-Si: Monolithically Integrated All-GaN Drivers for High-Voltage DC-DC Power Conversion
Authors: Hsia Chin , Lu Deng-Fong
Published: May 2022

This paper presents a novel integrated half-bridge driver architecture using GaN-on-Si process for high-speed and high-voltage DC-DC converters. The entire circuit includes only enhancement mode (E-mode) and depletion-mode (D-mode) GaN transistors. The high-side driver circuit adopts the E-stacked E/D-mode (EED) architecture, which can directly drive the gate of the high-side transistor with a low-voltage signal without using an additional level shifter, which simplifies the design and reduces propagation delay. In addition, the low-side power transistor is driven by stacking two D/E-mode devices. This architecture separates the high-side pulse from the low-side drive signal to prevent false triggering of the low-side driver. The designed fully integrated GaN driver can output a high-voltage pulse wave with an operating frequency greater than 1 MHz when the input voltage is greater than 200 V. The rise and fall times of the high-voltage pulse wave operating at a peak voltage of 200 V are 54.4 ns and 57.6 ns, respectively. The experimental results show that the circuit can effectively drive the half-bridge circuit and be applied to a buck converter. The designed buck converter can deliver up to 20.5 W of output power, and the maximum efficiency achieves 90.7%.
Use of Carbon and Basalt Fibers with Adhesives to Improve Physical and Mechanical Properties of Plywood
Authors: Núñez-Decap Mario , Barra-Rodríguez Yasna , Opazo-Carlsson Camila , Moya-Rojas Boris , Vidal-Vega Marcela , Opazo-Vega Alexander
Published: May 2022

Currently, wood is presented as an alternative to traditional building materials and to mitigate climate change. Chile is one of the eight largest wood producers in the world; therefore, wood-based products are an easily accessible resource. The aim of this research is to reinforce at laboratory scale plywood panels with basalt and carbon engineer fibers using epoxy resin and polyvinyl acetate as an adhesive system to improve their physical and mechanical properties. Three-point static bending and Janka hardness tests were carried out. The results showed a better performance in the reinforced boards, which showed an increase in Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) properties in the parallel direction of about 48.2% and 52.8%, respectively. Additionally, for the perpendicular direction, there was an increase of 52.0% and 102.9%, respectively. On the other hand, the Fiber Reinforced Polymer (FRP) plywood panels showed an increase of at least 37% on the Janka hardness property, obtaining higher results with the polyvinyl acetate (PVA) adhesive. Finally, FRP–plywood, PVA–BF and PVA–CF may be a new option for composite wood materials, with their ductile behavior and superior mechanical properties, especially in the perpendicular direction, where the increases were greater than those shown in unreinforced plywood.
Anti-Obesity Activities of Standardized Ecklonia stolonifera Extract in 3T3-L1 Preadipocytes and High-Fat-Diet-Fed ICR Mice
Authors: Han Xionggao , Choi Sun-Il , Men Xiao , Lee Se-Jeong , Jin Heegu , Oh Hyun-Ji , Kim Eunjin , Kim Jongwook , Lee Boo-Yong , Lee Ok-Hwan
Published: May 2022

The purpose of this study was to prepare a clinical trial test material (ESETM, test material of Ecklonia stolonifera extract) to develop a health functional food based on its anti-obesity effect. The anti-obesity effect of ESETM was evaluated in 3T3-L1 adipocytes and obese mice fed a high-fat diet (HFD) to confirm its nonclinical trial effect before application in clinical trial. Adipogenesis is a process of preadipocyte differentiation that causes an increase in the production of reactive oxygen species (ROS) and lipid accumulation. In vitro study results indicated that ESETM outstandingly inhibits the production of ROS and lipid accumulation during adipogenesis and lipogenesis. In vivo, ESETM-treated ICR mice had reduced HFD-induced weight change, food efficiency ratio, adipose tissue weight, liver weight and showed improved serum lipid profiles. Our results show that ESETM inhibits weight change by regulating the adipogenesis, lipogenesis, lipolysis, and thermogenesis pathways.
Ultrastructural Features of Keratoacanthoma—Clinical Implications
Authors: Temelie-Olinici Doinița , Bărgăoanu Petronela , Foia Iolanda , Onofrei Pavel , Dimitriu Cristina Daniela , Botez Ana-Emanuela , Stoica Laura , Grecu Vasile-Bogdan , Cotrutz Elena-Carmen
Published: May 2022

Over the years, keratoacanthomas have been described as some of the most common skin lesions with the potential for malignant transformation, thus constituting an important risk factor for the development of squamous cell carcinoma. The quantification of the risk of malignant transformation is conditioned by the clinical–morphological and etiopathogenic variability of these lesions, with a negative impact on diagnostic and therapeutic management. In this sense, the main objective of this research is to characterize from an ultrastructural perspective the specific tumour microenvironment, by using a technique with a higher resolution power than photon microscopy. Keratoacanthoma lesions from 25 patients were excised from healthy tissue and then processed by classical electron microscopy and examined with the Philips CM100 microscope. The electron microscopic study revealed structural details suggestive of malignant transformation, capturing changes at both cytoplasmic and membranous levels. The identification and description of the ultrastructural morphological substrate favouring the evolution and progression of the studied lesions correlates directly with the improvement of the prognosis and quality of life of these patients.
Determination and Evaluation of a Three-Wheeled Tilting Vehicle Prototype’s Dynamic Characteristics
Authors: Navikas Deividas , Pitrėnas Aurelijus
Published: May 2022

When a new vehicle is being developed, the parameters of the electric motor, battery modules, and control algorithms have a significant impact on its dynamic characteristics. This paper presents a method of determining the dynamic characteristics of a three-wheeled tilting vehicle created by AKO team. In order to achieve this, the acceleration values in theoretical calculations were determined and were verified by experimental field tests using a three-wheeled vehicle prototype. Theoretical calculations include the determination of speed, dynamic factor, air resistance, and traction force. The theoretical calculation of the above-mentioned dynamic factors also involves the experimental determination of the drag coefficient, which was performed in a wind tunnel using a scaled-down (1:16) three-wheeled vehicle model. Field tests were conducted to determine acceleration data using two accelerometers, one of which was used for the synchronization of the calculated acceleration data with experimentally obtained acceleration data. Obtained data from very sensitive accelerometer were filtered using a Butterworth second-order low-pass filter. Results show compliance between the calculated and measured accelerations, which means that theoretical calculations were verified by experimental measurements.
Supporting Clinical COVID-19 Diagnosis with Routine Blood Tests Using Tree-Based Entropy Structured Self-Organizing Maps
Authors: Sargiani Vagner , De Souza Alexandra A. , De Almeida Danilo Candido , Barcelos Thiago S. , Munoz Roberto , Da Silva Leandro Augusto
Published: May 2022

Data classification is an automatic or semi-automatic process that, utilizing artificial intelligence algorithms, learns the variable and class relationships of a dataset for use a posteriori in situations where the class result is unknown. For many years, work on this topic has been aimed at increasing the hit rates of algorithms. However, when the problem is restricted to applications in healthcare, besides the concern with performance, it is also necessary to design algorithms whose results are understandable by the specialists responsible for making the decisions. Among the problems in the field of medicine, a current focus is related to COVID-19: AI algorithms may contribute to early diagnosis. Among the available COVID-19 data, the blood test is a typical procedure performed when the patient seeks the hospital, and its use in the diagnosis allows reducing the need for other diagnostic tests that can impact the detection time and add to costs. In this work, we propose using self-organizing map (SOM) to discover attributes in blood test examinations that are relevant for COVID-19 diagnosis. We applied SOM and an entropy calculation in the definition of a hierarchical, semi-supervised and explainable model named TESSOM (tree-based entropy-structured self-organizing maps), in which the main feature is enhancing the investigation of groups of cases with high levels of class overlap, as far as the diagnostic outcome is concerned. Framing the TESSOM algorithm in the context of explainable artificial intelligence (XAI) makes it possible to explain the results to an expert in a simplified way. It is demonstrated in the paper that the use of the TESSOM algorithm to identify attributes of blood tests can help with the identification of COVID-19 cases. It providing a performance increase in 1.489% in multiple scenarios when analyzing 2207 cases from three hospitals in the state of São Paulo, Brazil. This work is a starting point for researchers to identify relevant attributes of blood tests for COVID-19 and to support the diagnosis of other diseases.
Hole Cleaning Performance of V-Shaped Hole Cleaning Device in Horizontal Well Drilling: Numerical Modeling and Experiments
Authors: Zhou Yunjian , He Yufa , Li Zijian , Ju Guoshuai
Published: May 2022

The application of hole cleaning devices can effectively solve the hole cleaning problem during the drilling of horizontal wells. Improving the hole cleaning performance is directly related to subsequent drilling time and cost. In this paper, the solid–liquid two-phase hydrodynamic characteristics under the action of the V-shaped hole cleaning device for drilling horizontal wells were studied experimentally and numerically. The decay law of spiral flow induced by the V-shaped hole cleaning device was obtained numerically using the commercial CFD code “Fluent” by changing the blade rotational speed, blade helix angle, and consistency coefficient of drilling fluid. The helix angle will cause the flow direction of local fluid to deflect. The swirl intensity of spiral flow increases significantly with an increase in rotational speed. The hole cleaning performance was better when the helix angle was from about 10 to 20 degrees. Increasing the fluid consistency coefficient will rapidly make the spiral flow decay, resulting in a shorter effective action distance and a worse hole cleaning effect. The simulation results were validated against the experimental results of the flow loop. Both experimental and simulation results showed that the hole cleaning performance was improved by using the V-shaped hole cleaning device. The very good agreement achieved between the results has presented an opportunity to study the hole cleaning effect of a hole cleaning device in unsteady state conditions. The results will provide theoretical guidance for efficient hole cleaning using V-shaped hole cleaning devices for horizontal well drilling.
Blockchain Based Smart-Grid Stackelberg Model for Electricity Trading and Price Forecasting Using Reinforcement Learning
Authors: Moti Md Mahraj Murshalin Al , Uddin Rafsan Shartaj , Hai Md. Abdul , Saleh Tanzim Bin , Alam Md. Golam Rabiul , Hassan Mohammad Mehedi , Hassan Md. Rafiul
Published: May 2022

A smart grid is an intelligent electricity network that allows efficient electricity distribution from the source to consumers through telecommunication technology. The legacy smart grid follows the centralized oligopoly marketplace for electricity trading. This research proposes a blockchain-based electricity marketplace for the smart grid environment to introduce a decentralized ledger in the electricity market for enabling trust and traceability among the stakeholders. The electricity prices in the smart grid are dynamic in nature. Therefore, price forecasting in smart grids has paramount importance for the service providers to ensure service level agreement and also to maximize profit. This research introduced a Stackelberg model-based dynamic retail price forecasting of electricity in a smart grid. The Stackelberg model considered two-stage pricing between electricity producers to retailers and retailers to customers. To enable adaptive and dynamic price forecasting, reinforcement learning is used. Reinforcement learning provides an optimal price forecasting strategy through the online learning process. The use of blockchain will connect the service providers and consumers in a more secure transaction environment. It will help tackle the centralized system’s vulnerability by performing transactions through customers’ smart contracts. Thus, the integration of blockchain will not only make the smart grid system more secure, but also price forecasting with reinforcement learning will make it more optimized and scalable.
The Process of Natural and Styrene–Butadiene Rubbers Biodegradation by Lactobacillus plantarum
Authors: Olejnik Tomasz P. , Pietras Marta , Sielski Jan , Śliżewska Katarzyna , Sobiecka Elżbieta
Published: May 2022

The ability of Lactobacillus plantarum to degrade different mixtures of styrene–butadiene and natural rubbers was investigated. In experiments, 12 various compositions of rubber waste mixtures were investigated. Lactobacillus plantarum cultivation was carried out in a medium with the addition of individual mixtures at the temperature of 30 °C for 14 days. The presence of cellulose on the surface of bioreactors indicated the activity of bacteria. After cultivation, the rubber mixtures were tested again. Analyses of the elemental composition and mass balance of waste were carried out. The experiments showed that the culture media supplemented by various natural rubber mixtures allowed bacteria to produce bacterial cellulose. The mean thickness of bacterial cellulose was 3–6 mm after 14 days of culturing. In samples where the cellulose appeared, about 4% average mass loss was observed. The average carbon content in the rubber material used as the carbon source for bacteria, before the culture process, was about 89.07–95.40%. After 14 days of culturing, the carbon content was reduced from 31.15% to 56.45–65.7%.
Evaluation of the Wind Environment around Multiple Urban Canyons Using Numerical Modeling
Authors: Son Minu , Lee Jeong-In , Kim Jae-Jin , Park Soo-Jin , Kim Daegi , Kim Do-Yong
Published: May 2022

This study aimed to evaluate the wind environment in step-up and step-down urban canyons through a computational numerical experiment using the computational fluid dynamics (CFD) model. Spatial structural conditions were considered according to the location of high-rise buildings, and the changing wind patterns inside canyons were compared and analyzed by varying the building heights. Under the step-up to step-down condition, wind velocity inside the canyon weakened, a vertical vortex formed, and vertical air flow separated; additionally, in shallow and deep canyons, wind velocity and detailed flow differed slightly according to each additional condition. For the step-down to step-up condition, the building located in the center appeared to be isolated, and a general wind environment phenomenon consistent with the step-up and step-down structures was observed. However, depending on the isolated area, an additional roof-top canyon was formed, and the wind field in the canyon was found to affect the wind velocity and detailed flow in other canyons. The wind velocity components of the inflow and outflow winds into the canyon differed based on the step-up to step-down or step-down to step-up conditions, and according to the conditions in the first and second canyons. Furthermore, the vertical wind velocity components were greatly affected by the step-up and step-down structures. Accordingly, the height and structural location of the building could affect various phenomena, such as the separation of vortices and air currents inside the canyon, and a variable wind environment was formed according to a series of conditions for the building.
Acinetobacter baumannii and Its Relationship to Carbapenem Resistance: A Meta-Analysis
Authors: Rodrigues Diego Lucas Neres , Costa Francielly Morais Rodrigues da , Silva Wanderson Marques da , Aburjaile Flavia , Azevedo Vasco
Published: May 2022

Infections by antibiotic-resistant bacteria are a significant and complex global health issue. In this context, Acinetobacter baumannii is particularly important because of its ability to withstand treatments by β-lactams, such as carbapenem. The objective of this work was to investigate, through systematic analysis and meta-analysis, the chance of resistance to carbapenem in A. baumannii strains. For this, a search was conducted for the PubMed and Cochrane databases based on the keywords: “Acinetobacter baumannii” AND “beta-lactam” OR “penicillin” OR “cephalosporin” OR “cephamycin” OR “carbapenem” OR “monobactam”. The initial search resulted in a total of 90,475 articles. It was filtered based on eligibility criteria, and eight articles were selected for analysis. An odds ratio value equivalent to 3.55 was obtained, indicating a high chance of resistance to the carbapenem of strains of the species. Therefore, it is supposed that A. baumannii infection cases have a high probability of not responding adequately to treatments based on carbapenem.