bluuebunny/crossref_metadata_2025 huggingface dataset:
G0S2 Gene Polymorphism and Its Relationship with Carcass Traits in Chicken
Authors: Yang Xin , Xian Yuanrong , Li Zhenhui , Wang Zhijun , Nie Qinghua
Published: April 2022

Gene single nucleotide polymorphisms can be used as auxiliary markers in molecular breeding and are an effective method to improve production performance. G0S2 is a key gene involved in regulating fat metabolism, but little research has been conducted on this gene regarding its role in poultry. In this study, the specialized commercial partridge chicken strain G0S2 gene was cloned and sequenced, and the relationship between the SNP sites on G0S2 and the carcass traits of chickens was investigated. The results showed that a total of seven SNPs were detected on G0S2 (g.102G > A, g.255G > A, g.349C > T, g.384A > G, g.386G > A, g.444G > A, g.556G > A). Two sites are located in the coding region and five sites are located in the 3′-UTR. SNPs located in the coding region are synonymous mutations. g.444G > A has a significant correlation with abdominal fat weight. The chickens with AG and GG genotypes have the highest abdominal fat weight, while the AA genotype is lower. The g.102G > A genotype has a significant correlation with live and abdominal fat weight. The live weight and abdominal fat weight of the chickens with AA and AG genotypes are at a higher level and have a larger gap than the GG genotype. Chickens with the AA genotype in g.556G > A had the lowest fat weight. The results of present study can provide practical information for molecular marker-assisted breeding of chicken carcass traits.
Preference for Shelters at Different Developmental Stages of Chinese Mitten Crab (Eriocheir sinensis)
Authors: Li Chunbo , Shen Chenchen , Feng Guangpeng , Huang Xiaorong , Li Xincang
Published: April 2022

A shelter is a good habitat for aquatic organisms, which could aid in avoiding cannibalism and facilitate predation. Chinese Mitten Crab (Eriocheir sinensis) is an important aquaculture species with troglodytism and nocturnal habit. To clarify the preference for shelters at different developmental stages of E. sinensis, different shelters (mud, sand, grass and rocks) were selected for comparison. These results indicated that juvenile crabs had a significant preference for grass; button-sized crabs preferred to hide in mud; and the favorite shelters for parent crabs were rocks, followed by mud. E. sinensis in three stages all showed concealing behavior. The concealing behavior of juvenile crabs was the most significant, followed by button-sized and parent crabs. Additionally, E. sinensis held a low hiding rate at night but a high hiding rate during the daytime due to nocturnal habits. These findings will help to better understand the habits of E. sinensis and provide a reference for resource restoration, habitat construction and the restoration of E. sinensis.
Emerging Concern with Imminent Therapeutic Strategies for Treating Resistance in Biofilm
Authors: Pandey Ramendra Pati , Mukherjee Riya , Chang Chung-Ming
Published: April 2022

Biofilm production by bacteria is presumed to be a survival strategy in natural environments. The production of biofilms is known to be influenced by a number of factors. This paper has precisely elaborated on the different factors that directly influence the formation of biofilm. Biofilm has serious consequences for human health, and a variety of infections linked to biofilm have emerged, rapidly increasing the statistics of antimicrobial resistance, which is a global threat. Additionally, to combat resistance in biofilm, various approaches have been developed. Surface modifications, physical removal, and the use of nanoparticles are the recent advances that have enabled drug discovery for treating various biofilm-associated infections. Progress in nanoparticle production has led to the development of a variety of biofilm-fighting strategies. We focus on the present and future therapeutic options that target the critical structural and functional characteristics of microbial biofilms, as well as drug tolerance mechanisms, such as the extracellular matrix, in this review.
The Collateral Effect of COVID-19 on the Epidemiology of Airborne/Droplet-Transmitted Notifiable Infectious Diseases in Taiwan
Authors: Tang Hung-Jen , Lai Chih-Cheng , Chao Chien-Ming
Published: April 2022

This study was conducted to compare the number of cases of airborne/droplet-transmitted notifiable infectious disease (NID) between the pandemic period (defined as from January 2020 to December 2021) and the pre-pandemic period (defined as the period from January 2018 to December 2019). The annual case numbers of airborne/droplet-transmitted NIDs from 2018 to 2021 were collected for comparison. Fourteen airborne/droplet-transmitted NIDs including measles, rubella, pertussis, influenza with severe complications, invasive pneumococcal diseases (IPD), Q fever, mumps, meningococcal meningitis, varicella, legionellosis, invasive Haemophilus influenzae type b infection, hantavirus syndrome, TB, and multidrug-resistant TB (MDRTB), were included for the analysis. Overall, the annual case number of these 14 airborne/droplet-transmitted NID was 11,930, 12,747, 9477, and 8268 in 2018, 2019, 2020, and 2021, respectively, and the overall incidence was 50.3, 53.6, 39.8, 34.6 per 100,000 populations in in 2018, 2019, 2020, and 2021. The case number of influenza with severe complications had the largest reduction from the pre-pandemic period to the pandemic period, with a reduction of 3076 cases, followed by TB (−2904), IPD (−490), mumps (−292), measles (−292), pertussis (−57), MDRTB (−43), rubella (−35), Q fever (−20), varicella (−12), meningococcal meningitis (−5), invasive H. influenzae type B (−4). In contrast, the case number of legionellosis increased from 492 during the pre-pandemic period to 676 during the pandemic period. In addition, hantavirus syndrome also increased from zero cases during the pre-pandemic period to three during the pandemic period. In conclusion, the occurrence of most airborne/droplet-transmitted NIDs, including both domestic and imported cases in Taiwan, was lower during the pandemic period than during the pre-pandemic period.
Oxidation and Antioxidation of Natural Products in the Model Organism Caenorhabditis elegans
Authors: Zhu An , Zheng Fuli , Zhang Wenjing , Li Ludi , Li Yingzi , Hu Hong , Wu Yajiao , Bao Wenqiang , Li Guojun , Wang Qi , Li Huangyuan
Published: April 2022

Natural products are small molecules naturally produced by multiple sources such as plants, animals, fungi, bacteria and archaea. They exert both beneficial and detrimental effects by modulating biological targets and pathways involved in oxidative stress and antioxidant response. Natural products’ oxidative or antioxidative properties are usually investigated in preclinical experimental models, including virtual computing simulations, cell and tissue cultures, rodent and nonhuman primate animal models, and human studies. Due to the renewal of the concept of experimental animals, especially the popularization of alternative 3R methods for reduction, replacement and refinement, many assessment experiments have been carried out in new alternative models. The model organism Caenorhabditis elegans has been used for medical research since Sydney Brenner revealed its genetics in 1974 and has been introduced into pharmacology and toxicology in the past two decades. The data from C. elegans have been satisfactorily correlated with traditional experimental models. In this review, we summarize the advantages of C. elegans in assessing oxidative and antioxidative properties of natural products and introduce methods to construct an oxidative damage model in C. elegans. The biomarkers and signaling pathways involved in the oxidative stress of C. elegans are summarized, as well as the oxidation and antioxidation in target organs of the muscle, nervous, digestive and reproductive systems. This review provides an overview of the oxidative and antioxidative properties of natural products based on the model organism C. elegans.
Sirtuin 3 Dependent and Independent Effects of NAD+ to Suppress Vascular Inflammation and Improve Endothelial Function in Mice
Authors: Cao Xiaoyun , Wu Yalan , Hong Huiling , Tian Xiao Yu
Published: April 2022

Atherosclerosis is initiated by endothelial cell dysfunction and vascular inflammation under the condition of hyperlipidemia. Sirtuin 3 (SIRT3) is a nicotinamide adenine dinucleotide (NAD+)-dependent mitochondrial deacetylase, which plays a key role in maintaining normal mitochondrial function. The present study tested whether endothelial-selective SIRT3 deletion accelerates vascular inflammation and oxidative stress, and assessed the protective effect of NAD+ to alleviate these changes in endothelial cells and in mouse models of atherosclerosis. We found that the selective deletion of SIRT3 in endothelial cells further impaired endothelium-dependent vasodilatation in the aorta treated with IL-1β, which was accompanied by upregulation of vascular inflammation markers and mitochondrial superoxide overproduction. Excepting the dysfunction of endothelium-dependent vasodilatation, such effects could be attenuated by treatment with NAD+. In human umbilical vein endothelial cells, SIRT3 silencing potentiated the induction of inflammatory factors by IL-1β, including VCAM-1, ICAM-1, and MCP1, and the impairment of mitochondrial respiration, both of which were alleviated by NAD+ treatment. In ApoE-deficient mice fed with a high-cholesterol diet, supplementation with nicotinamide riboside, the NAD+ precursor, reduced plaque formation, improved vascular function, and diminished vascular inflammation. Our results support the SIRT3-dependent and -independent of NAD+ to improve endothelial function in atherosclerosis.
Video Biomechanical Analysis of Shoulder Impact Kinematics in Tai-Otoshi and Morote-Seoi-Nage Judo Throws: A Cross-Sectional Study
Authors: Lota Kabir Singh , Błach Wiesław , Rydzik Łukasz , Ambroży Tadeusz , Angioi Manuela , Malliaropoulos Nikos
Published: April 2022

Background: Shoulder injuries in judo are common as the falling player (uke) lands. Two throws implicated in shoulder injury are tai-otoshi and morote-seoi-nage. Kinematic investigation can provide insight into possible shoulder injury mechanisms and allow for appropriate preventative measures to be suggested. We used two-dimensional (2D) video analysis to measure and compare: (a) the peak acceleration and (b) the peak velocity of uke’s shoulder when tai-otoshi and morote-seoi-nage were performed by elite adult judoka. Methods: Eight male participants were recruited from the Budokwai Judo Club in London, UK. The mean age, height, and weight of participants were 25.4 ± 5.2 years (18–34), 1.7 ± 0.0 m (1.7–1.8), and 75.0 ± 5.2 kg (66–80), respectively. Throws were recorded using an iPhone 6S camera and uploaded onto Kinovea for subsequent processing. Results: The peak acceleration (m/s2) was greater in tai-otoshi (71.6 ± 12.4) compared to morote-seoi-nage (67.9 ± 9.9), although this was statistically insignificant. The peak velocity (m/s) was significantly greater (p = 0.030) in tai-otoshi (5.1 ± 0.8) than in morote-seoi-nage (4.5 ± 0.6). Conclusions: A greater peak velocity in tai-otoshi suggests that the shoulder is subjected to increased loads upon impact. This may indicate that tai-otoshi carries a greater risk of shoulder injury. Nage-komi (repetitive throwing) practices in training should follow gradual loading principles—beginning with morote-seoi-nage, before moving to tai-otoshi, for example. We must be aware of any assumptions made in estimations of impact force, and future in vivo research is required to provide more definitive values. Meanwhile, coaches must continue to ensure that correct ukemi (breakfall) technique is displayed by athletes before performing throws.
Deep Neural Networks for Defects Detection in Gas Metal Arc Welding
Authors: Nele Luigi , Mattera Giulio , Vozza Mario
Published: April 2022

Welding is one of the most complex industrial processes because it is challenging to model, control, and inspect. In particular, the quality inspection process is critical because it is a complex and time-consuming activity. This research aims to propose a system of online inspection of the quality of the welded items with gas metal arc welding (GMAW) technology through the use of neural networks to speed up the inspection process. In particular, following experimental tests, the deviations of the welding parameters—such as current, voltage, and welding speed—from the Welding Procedure Specification was used to train a fully connected deep neural network, once labels have been obtained for each weld seam of a multi-pass welding procedure through non-destructive testing, which made it possible to find a correspondence between welding defects (e.g., porosity, lack of penetrations, etc.) and process parameters. The final results have shown an accuracy greater than 93% in defects classification and an inference time of less than 150 ms, which allow us to use this method for real-time purposes. Furthermore in this work networks were trained to reach a smaller false positive rate for the classification task on test data, to reduce the presence of faulty parts among non-defective parts.
An Overview of Position Sensorless Techniques for Switched Reluctance Machine Systems
Authors: Tang Xingtao , Sun Xiaodong , Yao Ming
Published: April 2022

Accurate real-time rotor position is indispensable for switched reluctance motors (SRM) speed and torque control. Traditional position sensors add complexity and potential failure risk to the system. Owing to the added advantages of high stability and low cost, the position sensorless method of SRMs has been extensively studied to advance its use in vehicles and construction machinery. This paper presents an overview of position sensorless control techniques from the perspective of whether the method requires the establishment of complex mathematical models. Various types of methods are compared for performance, such as speed regulation range, algorithm complexity, and requirement of the pre-stored parameter. A discussion is presented concerning current trends in technological development, which will facilitate the research addressing potentially effective methods for position estimation in SRM drive systems.
Seismic Behavior of a Steel Beam-to-Concrete-Filled Steel Tubular Column Connection Using External Diaphragms
Authors: Ramirez Ortiz Cristhian , Areiza Palma Gilberto , Gutierrez Amador Albio , Ramirez Duque Jose , Cano Buitron Ruth , Gonzales Escobar Luis
Published: April 2022

This paper investigates the seismic behavior of a steel beam-to-concrete-filled steel tubular column connection with external diaphragms. In addition to the multiple advantages observed for manufacturing and assembly, this type of connection is expected to provide an adequate plasticizing mechanism based on its ductility, energy dissipation and moment resistance capacity. However, guidelines have not been provided for this type of connection within the AISC 358 standard, which makes experimental studies under cyclic loads necessary. This work presents such a study, which was carried out in accordance with the FEMA 350 standard for earthquake-resistant structures. The results for the failure modes, hysteretic performance, strength and stiffness degradation, rigidity classification and energy dissipation are provided and analyzed. The results indicate that this connection exhibits large hysteretic loops and develops ductility and dissipation capacity, as expected. More importantly, the maximum rotation of the beam was 0.07 rad with a resistant moment above 80% of the beam capacity measured from the face of the column. Thus, the ductility design requirements for earthquake resistance are met according to the current regulations. Consequently, the proposed connection is suitable for use in special moment frame structures located in areas of high seismic threat.
Dynamic Characteristic Master Curve and Parameters of Different Asphalt Mixtures
Authors: Ma Shijie , Fan Liang , Ma Tao , Dong Zhao , Zhang Yuzhen , Zhang Xiaomeng
Published: April 2022

Using an AMPT tester and based on laboratory tests, this paper performed a comparative study on the dynamic characteristics of different asphalt mixtures, analyzed the influence of different asphalt binders on the characteristic parameters of the dynamic modulus master curve and the phase angle master curve of asphalt mixture, and expounds the evaluation function of the phase angle master curve for mixture relaxation characteristics. The results show that the modulus master curve parameters of the asphalt mixture are closely related to voids in the mineral aggregate, mixture density, and asphalt content of the asphalt mixture. For the same kind of asphalt mixture, because the gradation of mineral aggregate is fixed and the volume parameters are almost the same, the ultimate modulus of the mixture at different temperatures is unique; when the temperature changes or the asphalt changes, the shape parameter β of the modulus master curve changes regularly, which brings different dynamic responses, and the lower β will show the characteristics of a higher modulus. Asphalt is the source of the viscoelasticity of the asphalt mixture. Although the influence of particle gradation of the mixture will bring about the change of modulus, the phase angle of the mixture depends on the viscoelastic properties of asphalt, and the initial phase angle in the main curve is positively correlated with asphalt penetration and negatively correlated with the softening point and viscosity, while the peak phase angle A is negatively correlated with penetration, and the softening point viscosity is positively correlated. The viscoelastic interval, represented by ω, is negatively correlated with penetration but positively correlated with the softening point and viscosity. The peak position, parameter ωc, of the phase angle master curve can evaluate the relaxation characteristics of the mixture, and the crack resistance of different mixtures can be compared without complex model calculation. In the comparison of the relaxation time of asphalt mixture, the relaxation time of foam cold-recycled mixture is the largest, which is significantly higher than that of other forms of cement mixture; the emulsified asphalt cold-recycled mixture is equivalent to AC20 and LSPM30 mixtures; the SBS-modified asphalt mixture has the best relaxation characteristics.
HGG and LGG Brain Tumor Segmentation in Multi-Modal MRI Using Pretrained Convolutional Neural Networks of Amazon Sagemaker
Authors: Lefkovits Szidónia , Lefkovits László , Szilágyi László
Published: April 2022

Automatic brain tumor segmentation from multimodal MRI plays a significant role in assisting the diagnosis, treatment, and surgery of glioblastoma and lower glade glioma. In this article, we propose applying several deep learning techniques implemented in AWS SageMaker Framework. The different CNN architectures are adapted and fine-tuned for our purpose of brain tumor segmentation.The experiments are evaluated and analyzed in order to obtain the best parameters as possible for the models created. The selected architectures are trained on the publicly available BraTS 2017–2020 dataset. The segmentation distinguishes the background, healthy tissue, whole tumor, edema, enhanced tumor, and necrosis. Further, a random search for parameter optimization is presented to additionally improve the architectures obtained. Lastly, we also compute the detection results of the ensemble model created from the weighted average of the six models described. The goal of the ensemble is to improve the segmentation at the tumor tissue boundaries. Our results are compared to the BraTS 2020 competition and leaderboard and are among the first 25% considering the ranking of Dice scores.
Preparation of Nanoparticle-Loaded Microbubbles via an Electrohydrodynamic Atomization Process
Authors: Nie Xin-Bin , Wang Yong , Ran Xiong , Wu Ji-Chuan , Wei Ran , Yan Wei-Cheng
Published: April 2022

Microbubbles have been widely used in many research fields due to their outstanding physicochemical properties and unique structural characteristics, especially as ultrasonic contrast agents and drug delivery carriers. However, the stability of conventional microbubbles is generally poor, which limits the development of their applications. Loading nanoparticle to microbubbles has great potential in enhancing the stability of microbubbles. This paper reports for the first time the feasibility of one-step preparation of nanoparticle-loaded microbubbles by coaxial electrohydrodynamic atomization. Bovine serum albumin (BSA) was used as the model material of the bubble shell layer to study the effect of the loading of nanoparticles on the stability of microbubbles. The results show that the concentration of nanoparticles has a significant impact on the stability of microbubbles, and loading an appropriate amount of nanoparticles is helpful in improving the stability of microbubbles. The results also show that nanoparticle-loaded microbubbles with a size distribution in the range of 120–200 μm can be prepared under optimal conditions.
Overall High-Performance Near-Infrared Photodetector Based on CVD-Grown MoTe2 and Graphene Vertical vdWs Heterostructure
Authors: Du Wanying , Cheng Xing , Zhang Zhihong , Cheng Zhixuan , Xu Xiaolong , Xu Wanjing , Li Yanping , Liu Kaihui , Dai Lun
Published: April 2022

Two-dimensional (2D) materials, such as graphene and transition metal dichalcogenides (TMDCs), are highly appealing in the fields of electronics, optoelectronics, energy, etc. Graphene, with high conductivity and high carrier mobility, is an excellent candidate for transparent electrodes. TMDCs have remarkably strong light absorption in the range of visible to infrared wavelength. High-performance photodetectors are expected to achieve through the combination of graphene and TMDCs. Nowadays, near-infrared (NIR) photodetectors play significant roles in many areas. MoTe2 with bandgap energy of about 1.0 eV in its bulk form is a promising material for cost-saving NIR photodetectors. Thus far, only a few of the reported studies on NIR photodetectors built on MoTe2/graphene heterostructures have achieved high responsivity and short response time simultaneously in one device. In this study, we fabricate graphene–MoTe2–graphene vertical van der Waals heterostructure devices through chemical vapor deposition (CVD) growth, wet transfer method, and dry etching technique. Under 1064 nm laser illumination, we acquire responsivity of as high as 635 A/W and a response time of as short as 19 μs from the as-fabricated device. Moreover, we acquire higher responsivity of 1752 A/W and a shorter response time of 16 μs from the Al2O3-encapsulated device. Our research drives the application of 2D materials in the NIR wavelength range.
Prediction of Soil–Water Retention Curves of Road Base Aggregate with Various Clay Fine Contents
Authors: Zhang Qi , Cao Zhigang , Gu Chuan , Cai Yuanqiang
Published: April 2022

The invasion of clay fines can change the water retention properties of base layers significantly. There is no soil–water retention curve prediction equation that is capable of considering the effects of fines. In this study, the soil–water retention curves (SWRC) of road base aggregate with different fine contents (FC) were measured. The variations in inter-aggregate pores (formed by coarse grains) and intra-aggregate pores (formed by fines) with FC were deduced from the SWRC at different FCs. It was found that the inclusion of fines shifted and scaled the inter-aggregate pore distribution curves and scaled the intra-aggregate pore distribution curves. Based on this finding, a prediction equation for SWRC with consideration of the effects of FC was proposed. The feasibility of this equation was verified by comparing the predicted and measured results. The proposed model can be used to predict the SWRC of soil with different FCs.
Potentiometric Biosensor Based on Artificial Antibodies for an Alzheimer Biomarker Detection
Authors: Ribeiro Sónia Claúdia , Fernandes Rúben , Moreira Felismina T. C. , Sales Maria Goreti Ferreira
Published: April 2022

This paper presents a potentiometric biosensor for the detection of amyloid β-42 (Aβ-42) in point-of-care analysis. This approach is based on the molecular imprint polymer (MIP) technique, which uses covalently immobilised Aβ-42 to create specific detection cavities on the surface of single-walled carbon nanotubes (SWCNTs). The biosensor was prepared by binding Aβ-42 to the SWCNT surface and then imprinting it by adding acrylamide (monomer), N,N′-methylene-bis-acrylamide (crosslinker) and ammonium persulphate (initiator). The target peptide was removed from the polymer matrix by the proteolytic action of an enzyme (proteinase K). The presence of imprinting sites was confirmed by comparing a MIP-modified surface with a negative control (NIP) consisting of a similar material where the target molecule had been removed from the process. The ability of the sensing material to rebind Aβ-42 was demonstrated by incorporating the MIP material as an electroactive compound in a PVC/plasticiser mixture applied to a solid conductive support of graphite. All steps of the synthesis of the imprinted materials were followed by Raman spectroscopy and Fourier transform infrared spectroscopy (FTIR). The analytical performance was evaluated by potentiometric transduction, and the MIP material showed cationic slopes of 75 mV-decade−1 in buffer pH 8.0 and a detection limit of 0.72 μg/mL. Overall, potentiometric transduction confirmed that the sensor can discriminate Aβ-42 in the presence of other biomolecules in the same solution.
AIR-YOLOv3: Aerial Infrared Pedestrian Detection via an Improved YOLOv3 with Network Pruning
Authors: Shao Yanhua , Zhang Xingping , Chu Hongyu , Zhang Xiaoqiang , Zhang Duo , Rao Yunbo
Published: April 2022

Aerial object detection acts a pivotal role in searching and tracking applications. However, the large model, limited memory, and computing power of embedded devices restrict aerial pedestrian detection algorithms’ deployment on the UAV (unmanned aerial vehicle) platform. In this paper, an innovative method of aerial infrared YOLO (AIR-YOLOv3) is proposed, which combines network pruning and the YOLOv3 method. Firstly, to achieve a more appropriate number and size of the prior boxes, the prior boxes are reclustered. Then, to accelerate the inference speed on the premise of ensuring the detection accuracy, we introduced Smooth-L1 regularization on channel scale factors, and we pruned the channels and layers with less feature information to obtain a pruned YOLOv3 model. Meanwhile, we proposed the self-built aerial infrared dataset and designed ablation experiments to perform model evaluation well. Experimental results show that the AP (average precision) of AIR-YOLOv3 is 91.5% and the model size is 10.7 MB (megabyte). Compared to the original YOLOv3, its model volume compressed by 228.7 MB, nearly 95.5 %, while the model AP decreased by only 1.7%. The calculation amount is reduced by about 2/3, and the inference speed on the airborne TX2 has been increased from 3.7 FPS (frames per second) to 8 FPS.
The Interoperability of Learning Object Design, Search and Adaptation Processes in the Repositories
Authors: Gudoniene Daina , Staneviciene Evelina , Motiejunas Liudas
Published: April 2022

Learning environments ensure successful implementation of the learning process but not always the effective design of the e-learning objects (ELOs) and moreover, search and adaptation. A technological solution for the design of the learning objects, repositories, and the semantic web is needed. There are many open educational resources, but not many platforms assure the possibility to adapt learning objects. The existing developed multifunctional platforms do not ensure the effective ELOs adaptation as well as the process of design and adaptation in the multifunctional environment. They do not have an automatic search of ELOs in the semantic web, which is directly targeted to the specific objects in repositories of open educational resources and do not allow for adaptation of the already developed ELO by automatically assigning reusable objects. The structure of the papers consists of the literature review and overview of existing practices, research methodology, research results description and conclusions provided by authors. The objective of the research is to suggest, to teachers, a model for effective e-learning objects design, automatic search and adaptation processes in the multifunctional environment by developing a platform based on semantic technologies for e-learning objects design and adaptation.
Influence of Cynara cardunculus L. Phenolic Compounds on Pseudomonas putida Isolated from the Dairy Industry: Growth and Melanin Bioproduction
Authors: Ferraz Ana Rita , Pintado Cristina M. B. S. , Serralheiro Maria Luísa
Published: April 2022

Cynara cardunculus L. inflorescence infusion has been used for several centuries as curd in traditional cheese making, such as some highly prized Portuguese cheeses. To promote the sustainable use of all C. cardunculus plants, C. cardunculus extract leaves decoction (CL), inflorescence decoction (CI), chlorogenic acid (CA) (a compound in the plant leaves), and rosmarinic acid (RA) (a similar phenolic compound) solutions were tested for antimicrobial activity against bacteria that may appear on the cheese rind. The antimicrobial activity was evaluated by 15 bacterial strains using two different methodologies: solid and liquid. The influence of these extracts and the phenolic compounds on melanin bioproduction by Pseudomonas putida ESACB 191 was also studied. CA and RA (1 mg/mL) showed antimicrobial activity. CL and CA reduced P. putida ESACB 191 growth in the liquid assay and melanin bioproduction by 6.20 Log CFU/mL and 50%, respectively. Cynarin, CA, and its derivates were identified as the main phenolic compounds (52%) of CL, which may justify its inhibitory action on bacterial growth and melanin bioproduction. Thus, future perspectives include the application of CL extracts with antimicrobial activity in edible films and/or coatings to applied in cheese rind to increase the shelf time.
Effect of Formation Size on Flocking Formation Performance for the Goal Reach Problem
Authors: AlMuhaideb Sarab , Touir Ameur , Alshraihi Reem , Altwaijry Najwa , Qasem Safwan
Published: April 2022

Flocking is one of the swarm tasks inspired by animal behavior. A flock involves multiple agents aiming to achieve a goal while maintaining certain characteristics of their formation. In nature, flocks vary in size. Although several studies have focused on the flock controller itself, less research has focused on how the flock size affects flock formation and performance. In this study, we address this problem and develop a simple flock controller for goal-zone-reaching tasks. The developed controller is intended for a two-dimensional environment and can handle obstacles as well as integrate an additional invented feature, called sensing power, in order to simulate the natural dynamics of migratory birds. This controller is simulated using the NetLogo simulation tool. Several experiments were conducted with and without obstacles, accompanied by changes in the flock size. The simulation results demonstrate that the flock controller is able to successfully deliver the flock to the goal zone. In addition, changes in the flock size affect multiple metrics, such as the time required to reach the goal (and, consequently, the time required to complete the flocking task), as well as the number of collisions that occur.
Prediction of Linear Cationic Antimicrobial Peptides Active against Gram-Negative and Gram-Positive Bacteria Based on Machine Learning Models
Authors: Söylemez Ümmü Gülsüm , Yousef Malik , Kesmen Zülal , Büyükkiraz Mine Erdem , Bakir-Gungor Burcu
Published: April 2022

Antimicrobial peptides (AMPs) are considered as promising alternatives to conventional antibiotics in order to overcome the growing problems of antibiotic resistance. Computational prediction approaches receive an increasing interest to identify and design the best candidate AMPs prior to the in vitro tests. In this study, we focused on the linear cationic peptides with non-hemolytic activity, which are downloaded from the Database of Antimicrobial Activity and Structure of Peptides (DBAASP). Referring to the MIC (Minimum inhibition concentration) values, we have assigned a positive label to a peptide if it shows antimicrobial activity; otherwise, the peptide is labeled as negative. Here, we focused on the peptides showing antimicrobial activity against Gram-negative and against Gram-positive bacteria separately, and we created two datasets accordingly. Ten different physico-chemical properties of the peptides are calculated and used as features in our study. Following data exploration and data preprocessing steps, a variety of classification algorithms are used with 100-fold Monte Carlo Cross-Validation to build models and to predict the antimicrobial activity of the peptides. Among the generated models, Random Forest has resulted in the best performance metrics for both Gram-negative dataset (Accuracy: 0.98, Recall: 0.99, Specificity: 0.97, Precision: 0.97, AUC: 0.99, F1: 0.98) and Gram-positive dataset (Accuracy: 0.95, Recall: 0.95, Specificity: 0.95, Precision: 0.90, AUC: 0.97, F1: 0.92) after outlier elimination is applied. This prediction approach might be useful to evaluate the antibacterial potential of a candidate peptide sequence before moving to the experimental studies.
High-Performance Five-Phase Axial Flux Permanent Magnet Generator for Small-Scale Vertical Axis Wind Turbine
Authors: Wirtayasa Ketut , Hsiao Chun-Yu , Yang Nien-Che
Published: April 2022

Commonly, electrical energy is generated by using non-renewable energy such as natural gas, coal, and oil. As electrical energy is a basic asset for the development of a region, its utilization is increasing every year, which causes the existence of non-renewable energy to decrease every year. This issue is becoming a serious concern all over the world, which encourages every country to harness energy from renewable energy. Wind energy is a promising candidate for generating electricity today. In wind turbine generation, a three-phase generator is usually used. Along with the rapid development of power electronic devices and efforts to improve generator performances, the use of a multiphase system is considered important for harnessing energy from the wind more efficiently. In this study, a five-phase system is proposed to upgrade the output power and power density of the most qualified AFPMG in the previous study. The Taguchi optimization method is employed to obtain the lowest total harmonic distortion (THD) of the on-load voltage waveform. In addition to the Taguchi method, an Artificial Neural Network (ANN) is also employed to compare the results from the Taguchi method and the results are proven to have an excellent relationship. The data processed for Taguchi and ANN methods are strongly helped by using the finite element method from the Ansys Maxwell software. The performances of the proposed five-phase axial flux permanent magnet generator (FP-AFPMG) show good improvement, especially in THD, ripple torque, and ripple in the rectified voltage.
A Design Method for Low-Pressure Venturi Nozzles
Authors: O’Hern Hannah , Murphy Timothy , Zhang Xiang , Liburdy James , Abbasi Bahman
Published: April 2022

The purpose of this work is to provide empirical design models for low-pressure, subsonic Venturi nozzles. Experimentally validated simulations were used to determine the effect of nozzle geometry and operating conditions on the suction ratio (ratio of suction mass flow rate to motive mass flow rate) of low-pressure, subsonic Venturi nozzles, over a wide range of geometries and operating conditions, through a parametric study. The results of the parametric study were used to develop seven empirical models, each with a different range of applicability or calculating a different indicator of nozzle performance (i.e., suction ratio, momentum ratio, or dynamic pressure ratio), of the Venturi nozzles using a constrained multi-variable global optimization method. Of the seven empirical models, the best models were found to be those for low- (less than one) and high-suction ratios (greater than one), with mean absolute percentage errors of 5% and 18%, respectively. These empirical models provide a design tool for subsonic, low-pressure Venturi nozzles that is more than an order of magnitude more accurate than a governing equation approach or conventional flow head calculations. These newly-developed empirical models can be applied for initial nozzle design when precise suction ratios are required.
The Conformal Cosmological Potential
Authors: Cotsakis Spiros , Klaoudatou Ifigeneia , Kolionis Georgios , Miritzis John , Trachilis Dimitrios
Published: April 2022

We discuss qualitative features of the conformal relation between certain classes of gravity theories and general relativity, common to different themes such as f(R), Brans-Dicke-type, and string theories. We focus primarily on the frame relations of the fields involved, slice energy, traceless and Palatini extensions, and selected cosmological applications.
Evaluation of WRF Cumulus Parameterization Schemes for the Hot Climate of Sudan Emphasizing Crop Growing Seasons
Authors: Musa Abuelgasim I. I. , Tsubo Mitsuru , Ma Shaoxiu , Kurosaki Yasunori , Ibaraki Yasuomi , Ali-Babiker Imad-Eldin A.
Published: April 2022

High spatiotemporal resolution climate data are essential for climate-related impact studies. The Weather Research and Forecasting (WRF) model is widely used to downscale climate data for different regions with regional-specific physics configurations. This study aimed to identify robust configurations of the WRF model, especially cumulus parameterization schemes, for different climatic zones of Sudan. We focused on wet season (June–September) rainfall and dry season (November–February) temperature, which are determinants of summer crop and irrigated wheat yields, respectively. Downscaling experiments were carried out to compare the following schemes: Betts–Miller–Janjic (BMJ), improved Kain–Fritch (KFT), modified Tiedtke (TDK), and Grell–Freitas (GF). Results revealed that the BMJ performed better for wet season rainfall in the hyper-arid and arid zones; KFT performed better for rainfall in July and August in the semi-arid zone where most summer crops are cultivated. For dry season temperature, the BMJ and TDK outperformed the other schemes in all three zones, except that the GF performed best for the minimum temperature in December and January in the arid zone, where irrigated wheat is produced, and in the semi-arid zone. Specific parameterization schemes therefore need to be selected for specific seasons and climatic zones of Sudan.
Assessment of the Atmospheric Deposition of Heavy Metals and Other Elements in the Mountain Crimea Using Moss Biomonitoring Technique
Authors: Nekhoroshkov Pavel , Peshkova Alexandra , Zinicovscaia Inga , Vergel Konstantin , Kravtsova Alexandra
Published: April 2022

The atmospheric depositions of heavy metals and other elements on the territory of Crimean Mountains in 2015 was assessed using the moss biomonitoring technique. The neutron activation analysis performed at the installation REGATA of the IBR-2 reactor was used for the determination of the mass fractions of 34 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Yb, Ta, Th, and U). Factor analysis, concentration factors, and enrichment factors were used to reveal possible sources of elements in the mosses. The main contributor to the deposition of elements on the mosses was the weathering of rock materials. The second group of elements included Br and I. The agriculture and marine sources of emissions were found to be important factors of atmospheric Br and I, respectively. The representing maps of the distribution of heavy metals and other elements revealed high levels of elements at the South coast of Crimea and near the city of Simferopol. The comparison of the obtained data with the data of biomonitoring studies performed for other mountain regions showed higher levels of Al, V, Cr, Fe, Ni, and As than in the mosses from Bulgaria, Macedonia, and Norway, but lower than in the mosses from Georgia, Turkey, Romania, and Northern Serbia. The presented results could serve as a basis for future monitoring research.
Variability of Near-Surface Aerosol Composition in Moscow in 2020–2021: Episodes of Extreme Air Pollution of Different Genesis
Authors: Gubanova Dina Petrovna , Vinogradova Anna Aleksandrovna , Iordanskii Mikhail Alekseevich , Skorokhod Andrey Ivanovich
Published: April 2022

During 2020–2021, a comprehensive experiment was conducted to study the composition of near-surface atmospheric aerosol in Moscow. The paper considers the experimental data together with synoptic and meteorological conditions. Attention is focused on six episodes of extremely high aerosol mass concentration values: in March and October 2020, as well in March, April, May and July 2021. In all these cases (and only in them), the average daily mass concentration of PM10 aerosol exceeded the Maximum Permissible Concentration (MPC) value (according to Russian standards, 60 μg/m3). The origin of the aerosol during these periods of extreme pollution is revealed, which is the main result of the work. It was shown that the July episode of 2021 was associated with a local intensive anthropogenic source that arose as a result of the active dismantling and demolition of multistory industrial buildings. The remaining spring and autumn episodes were caused by atmospheric transport of both smoke aerosol from various regions with strong biomass fires and dust aerosol from arid zones of the south of European territory of Russia (ETR) with dust wind storms. The cases of atmospheric pollution transport to Moscow region from the other regions are confirmed with the help of air mass transport trajectories (HYSPLIT 4 model) and MERRA-2 reanalysis data on black carbon and/or dust distribution in the atmosphere over ETR. Differences in the elemental composition of the near-surface aerosol of Moscow air during periods with extremely high aerosol concentrations are analyzed in comparison with each other and with unperturbed conditions for the season.
Quantification of Outdoor Thermal Comfort Levels under Sea Breeze in the Historical City Fabric: The Case of Algiers Casbah
Authors: Arrar Fawzi Hicham , Kaoula Dalel , Matallah Mohamed Elhadi , Abdessemed-Foufa Amina , Taleghani Mohammad , Attia Shady
Published: April 2022

Thermal comfort in cities is an influential factor for citizens’ wellbeing and life quality. Urban microclimate studies have gained popularity following increasing urbanization trends and global climate change in recent years. Urban fabric and morphology in traditional cities represent a unique pattern both spatially and climatically. However, few studies have investigated traditional cities’ urban thermal comfort conditions. Therefore, this study aimed to assess the thermal comfort in different subspaces of Algiers Casbah’s historic urban fabric, which falls in the hot Mediterranean climate (Csa). This research evaluated the human thermal sensation by applying the physiological equivalent temperature (PET) index. The methodology used was a mixed approach, including field measurements, calculations, and a survey questionnaire. The results indicate the presence of a high-stress level during the measurement periods, and notable differences between the subspaces in January (ΔPETMax.Jan = 3.7 °C) and August (ΔPETMax.Aug = 2.2 °C). The highest discomfort was recorded in spaces with collapsed buildings, especially during the hot hours of the day. The findings also highlight a strong impact of the sky view factor on the mean radiant temperature (Tmrt) and the physiological equivalent temperature (PET). The study discusses recommendations and ways to improve the design of outdoor spaces and relieve heat stress in the streets of traditional cities. Finally, this work helps urban managers and heritage conservators in urban rehabilitation policies concerning outdoor microclimate improvement.
Monitoring Temperature Variation in Rising Small Defunct Volcano on Jeju Island, Republic of Korea, Using High-Resolution Sentinel-2 Images
Authors: Yoon Seong Uk , Ahn Jinhyun , Kim Yoon Seok , Han Gyung Deok , Chung Yong Suk , Lee Seung-Jae
Published: April 2022

Global warming is not an expectation but a reality in the “oreums” (common local name for rising, small defunct volcanoes on Jeju Island, Republic of Korea). The oreums exhibit wide biodiversity. However, their ecology is threatened by its associated climate change and their ecological changes have rarely been monitored or recorded. We used three years of Sentinel-2 image data to generate a normalized difference vegetation index (NDVI) map of the Geum-oreum area. We found that the NDVI was highly associated with temperature, implying that Sentinel-2 images could be utilized to monitor the temperature variation in the oreums to assist in planning and preparation to conserve their ecosystems before they are jeopardized. The results indicated that the NDVI maps derived from Sentinel-2 images were highly associated with temperature in Geum-oreum. We expect this method could be applied in other regions to detect temperature variation for ecological management planning in large areas (such as forests).
Land-Use Regression Modeling to Estimate NO2 and VOC Concentrations in Pohang City, South Korea
Authors: Choi Hee-Jin , Roh Young-Man , Lim Young-Wook , Lee Yong-Jin , Kim Ki-Youn
Published: April 2022

Land-use regression (LUR) has emerged as a promising technique for air pollution modeling to obtain the spatial distribution of air pollutants for epidemiological studies. LUR uses traffic, geographic, and monitoring data to develop regression models and then predict the concentration of air pollutants in the same area. To identify the spatial distribution of nitrogen dioxide (NO2), benzene, toluene, and m-p-xylene, we developed LUR models in Pohang City, one of the largest industrialized areas in Korea. Passive samplings were conducted during two 2-week integrated sampling periods in September 2010 and March 2011, at 50 sampling locations. For LUR model development, predictor variables were calculated based on land use, road lengths, point sources, satellite remote sensing, and population density. The averaged mean concentrations of NO2, benzene, toluene, and m-p-xylene were 28.4 µg/m3, 2.40 µg/m3, 15.36 µg/m3, and 0.21 µg/m3, respectively. In terms of model-based R2 values, the model for NO2 included four independent variables, showing R2 = 0.65. While the benzene and m-p-xylene models showed the same R2 values (0.43), toluene showed a lower R2 value (0.35). We estimated long-term concentrations of NO2 and VOCs at 167,057 addresses in Pohang. Our study could hold particular promise in an epidemiological setting having significant health effects associated with small area variations and encourage the extended study using LUR modeling in Asia.
Comments on Computation of Free-Free Transitions in Atomic Physics
Authors: Bhatia Anand K. , Sucher Joseph
Published: April 2022

The amplitude T for ‘free-free’ processes such as bremsstrahlung or photoabsorption by an electron in the continuum in the presence of an external field, is usually written as the matrix element of the radiation operator taken between two continuum states. However, unlike the case when at least one of the states is bound, as in radiative transitions, electron capture or the photo-effect, this expression contains unphysical term, proportional to a delta function, and is not really the physical amplitude Tphys. We first give an a priori definition of Tphys in terms of the scattering parts of the continuum functions, which does not have this delta function term and has an obvious interpretation in terms of time-ordered diagrams. We then show that when the formal amplitude T is modified by a long-distance cutoff, the modified form Tα approaches Tphys as the cutoff is removed. The modified form may be used as the basis for calculation and approximations without the need to introduce further cutoffs at a later stage.