bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Analyses of Cell-Free DNA in Pancreatic Juice or Bile for Diagnosing Pancreatic Duct and Biliary Tract Strictures
Authors: Nagai Kosuke , Kuwatani Masaki , Hirata Koji , Suda Goki , Hirata Hajime , Takishin Yunosuke , Furukawa Ryutaro , Kishi Kazuma , Yonemura Hiroki , Nozawa Shunichiro , Sugiura Ryo , Kawakubo Kazumichi , Sakamoto Naoya
Published: November 2022

Poor prognosis of pancreaticobiliary malignancies is attributed to intrinsic biological aggressiveness and the lack of reliable methods for early diagnosis. This study aimed to evaluate the feasibility and availability of pancreatic juice- and bile-derived cell-free DNA (cfDNA) for diagnosing pancreaticobiliary strictures. From October 2020 to February 2022, pancreatic juice or bile was obtained from 50 patients with pancreaticobiliary strictures during endoscopic retrograde cholangiopancreatography. cfDNAs extracted from the samples were analyzed using next-generation sequencing and a cancer gene panel. The obtained cfDNAs, genetic data and clinical information were analyzed for diagnosis. cfDNA concentrations in pancreatic juice were higher in the intraductal papillary mucinous neoplasm group than in the other groups, whereas those in bile were similar in all groups. In pancreatic juice, the sensitivity, specificity and positive and negative predictive values of cfDNA analyses were 33%, 100%, 100% and 71.4%, respectively, whereas those of cytological analyses were 0%, 100%, 0% and 62.5%, respectively. In bile, those of cell-free DNA analyses were 53%, 75%, 89.5% and 28.6%, respectively, whereas those of cytological analyses were 19%, 100%, 100% and 16%, respectively. In conclusion, pancreatic juice- and bile-derived cfDNA is a novel liquid biopsy tool that can diagnose pancreaticobiliary strictures.
Pacemaker Implantation in a Patient with Isolated Persistent Left Superior Vena Cava Draining into the Left Atrium: A Case Report and Brief Literature Review
Authors: Totorean Iuliana-Claudia , Vacarescu Cristina , Cozma Dragoș , Luca Constantin-Tudor , Feier Horea , Lazăr Mihai-Andrei , Deme Maria-Anastasia , Stoica Svetlana , Arnautu Diana-Aurora , Gaiță Dan
Published: November 2022

Anomalies of the thoracic venous system are rare and usually discovered incidentally, but they become clinically relevant in the case of patients requiring cardiac device implantation. Persistent left superior vena cava is considered the most common venous drainage abnormality, with several anatomical variants that generate technical difficulties during pacemaker or defibrillator lead placement. We report a case of an isolated persistent left superior vena cava with abnormal drainage into the left atrium, associated with a hypoplastic right-sided superior vena cava, in a patient scheduled for permanent pacemaker implantation. Considering the patient’s anatomical characteristics, a transvenous approach proved unfeasible and the procedure was successfully accomplished via the surgical placement of a left ventricle epicardial lead. We aim to emphasize the clinical importance of such venous anomalies and to discuss the practical implications and challenges derived from these types of conditions, especially in the field of electrophysiology.
STEM Distance Teaching: Investigating STEM Teachers’ Attitudes, Barriers, and Training Needs
Authors: Tzafilkou Katerina , Perifanou Maria , Economides Anastasios A.
Published: November 2022

The aim of this study was to investigate STEM teachers’ attitude towards STEM Distance Teaching (DT), as well as their perceived barriers and training needs. A mixed survey was conducted on 158 STEM teachers in secondary education who taught their courses fully online due to COVID-19. The results revealed that STEM teachers perceive STEM DT quite positively, but their attitude can be affected by several factors, such as the efficiency of the schools’ digital infrastructure, as well as their gender, age, and STEM teaching subject. The qualitative thematic analysis identified several barriers to efficiently applying STEM DT, including the (i) lack of students’ interaction and engagement, (ii) inefficiency of digital infrastructure, (iii) lack of students’ and teachers’ digital skills, (iv) lack of space/equipment, and (v) increased teaching workload. The generated themes of training needs highlighted the need for targeted and adjusted training to every STEM discipline, as well as training on DT tools and pedagogies. Finally, the results indicated the STEM teachers’ need for psychological support and consulting.
Influence of Friction on the Formability of Fe-Zn-Coated IF Steels for Car Body Parts
Authors: Evin Emil , Tomáš Miroslav
Published: November 2022

This paper presents the formability results of galvanized Zn-Fe-based interstitial-free (IF) “galvanneal” steel sheets with different degrees of alloying. The Fe content of the Zn-Fe coatings was determined by titration method and the phase composition of the coatings was determined by raster electron microscopy with EDX analyzer. A deterioration of the adhesion of the Fe-Zn coating to the substrate was observed in the pre-alloyed coating. The applied modes of annealing and smooth rolling after the surface galvanization resulted in a change in the surface microgeometry parameters Ra and Pc. The suitability of the surface microgeometry of the used Zn-Fe-coated sheets was assessed using control diagrams and the capability indexes Cpk with respect to the defined specifications. The coefficient of friction was determined by dry friction cup test, and using Anticorit lubricant and microtene film as lubricants. With increasing Fe content in the coating, a slight increase in friction coefficient values was observed—a slight deterioration in formability. The results obtained indicate that for car body surface parts, the Fe content of the Zn-Fe coating should range from 7% to 12%.
Implementation of Nitration Processes in Artificial Ageing for Closer-to-Reality Simulation of Engine Oil Degradation
Authors: Besser Charlotte , Agocs Adam , Ristic Andjelka , Frauscher Marcella
Published: November 2022

During their service, engine oils suffer from various influencing parameters such as thermo-oxidative stress and nitration, hence, the accumulation of degradation products and the entry of contaminants. Accordingly, ICEs need to be able to operate satisfactorily, especially with a degraded lubricant, making it highly recommendable to use such oils for component testing in ICE development. Thus, a new nitrative thermo-oxidative ageing method is presented for closer-to-reality simulation of engine oil alteration with the intention to provide reproducibly aged oils for subsequent bench testing. With this method, a target used oil from field application was replicated and the comparability of oil condition in the lab vs. field regarding oxidation, nitration, additive depletion, and acidification amongst others was verified by conventional and advanced analyses. Special focus was laid on the identification of nitration products, proving them to be predominantly oxidized aromatic species or organophosphates. The presented method gives valuable benefit for the closer-to-reality ageing of engine oils in reasonable time frames with moderate costs and, hence, for the provision of test oils for ICE bench testing enabling rapid engine component assessment.
A Comparative Study on Hygric Properties and Compressive Strength of Ceramic Bricks
Authors: Stępień Piotr , Spychał Edyta , Skowera Karol
Published: November 2022

This article analyzes the results of capillary rise, compressive strength and water absorption tests on solid ceramic bricks from existing structures and demolition materials taken from 11 different structures. In addition (for more extensive interpretation and evaluation of porosity), tests were performed for the selected series of bricks using a mercury porosimeter (MIP) and a micro computed tomography (micro-CT). Contemporary bricks (2 series) were also evaluated for comparison purposes. The conducted tests indicate that bricks obtained from different sources are characterized by “individual” relation of compressive strength and porosity, and “individual” relation of water absorption coefficient and porosity. In addition, on the basis of the results obtained in the study, compared with the literature data, it can be deduced that ceramic bricks with a water absorption coefficient of less than 50 g/m2s0.5 are characterized by a compressive strength of more than 80 MPa. As the research shows, the properties of bricks even from a single building can differ one from another, which can result in varying durability even within a single building. When choosing a material during the renovation or restoration of facilities, it is important to perform tests on the physical and mechanical properties of the original material, which will be reused.
Effect of Two-Step Sintering on Properties of Alumina Ceramics Containing Waste Alumina Powder
Authors: Vukšić Milan , Žmak Irena , Ćurković Lidija , Kocjan Andraž
Published: November 2022

This study aims to evaluate the recycling potential of solid waste alumina powder (WAP) by utilization of the two-step sintering (TSS) process. For the study, WAP was collected as an industrial scrap after the machining process for the formation of green alumina compacts. The alumina samples were prepared according to the slip casting method by preparing suspensions containing commercial alumina with 0.8 μm average particle size and by adding up to 20 dwb. % (i.e., expressed on a dry weight basis) of WAP with 3.4 μm average particle size. The samples were sintered at optimized TSS conditions and compared with conventional one-step sintering (OSS) by conducting morphological analyses. The average grain size (AGS) was determined from the obtained field emission scanning electron microscopy (FESEM) images, while the sample porosity was calculated based on apparent densities. The obtained micrographs after TSS implementation revealed a partially textured microstructure. Furthermore, a comparison of the mechanical properties of alumina samples lacking or containing 20 dwb. % of WAP obtained after sintering is presented. The indentation fracture toughness (~3.2 MPa m1/2) and Vickers hardness data (~14.5 GPa) showed a positive effect of adding WAP to alumina samples. The slightly improved mechanical properties of ceramic samples containing waste alumina are a consequence of lower porosity, which is due to the remaining sintering additives in WAP. The collected results demonstrate the possibility of using TSS for sintering ceramic materials that contain WAP.
Ankle Injury Rehabilitation Robot (AIRR): Review of Strengths and Opportunities Based on a SWOT (Strengths, Weaknesses, Opportunities, Threats) Analysis
Authors: Shah Muhammad N. , Basah Shafriza N. , Basaruddin Khairul S. , Takemura Hiroshi , Yeap Ewe J. , Lim Chee C.
Published: November 2022

Generally, severity, any additional damage to the joint surface, and the optimal rehabilitation influence the recovery of an ankle injury. Optimal rehabilitation is the only approach for a human to heal as soon as possible. Ankle injury rehabilitation robots (AIRRs) are designed to fulfil the ideal rehabilitation by providing the required accuracy, consistency, and repeatability, compared to conventional rehabilitation methods. This review is to explore the performance of the existing AIRR using a SWOT analysis with a focus on the strengths and opportunities of an AIRR. Sources from journals and conference papers are selected for review after several screenings, according to the search conditions set by the authors. The results have shown a large group of AIRRs could accomplish all basic ankle motions and select parallel mechanisms to drive the foot platform. Most AIRRs provides crucial feedback sensors, such as position, torque, and angle. These factors determine the accuracy of the foot platform. Both the electrical/pneumatic actuation and wearable/platform-based AIRRs have their purpose for rehabilitation and must be considered as equal contributions to ankle injury rehabilitation research using robots. Opportunities to provide innovation to the already established AIRR research still exist in the ability to accommodate complex motion ankle rehabilitation exercises and to establish teaching and playback into the rehabilitation procedures for AIRRs. In general, the existing strengths of AIRRs provide advantages to patients where they can enhance the rehabilitation procedures while opportunities and knowledge gaps for AIRR research are still open to improvement.
Optimal Selection of Suspension and Tires for Vehicles’ Cornering Performance
Authors: Kwon Seong-Jin , Kim Tae-Lim , Kim Chan-Jung
Published: November 2022

It is difficult to accurately simulate the cornering performance of a vehicle using a simplified vehicle model; therefore, a proper evaluation process should be conducted from an experimental perspective. In addition, there are several possible combinations of subparts in suspension modules, such as springs, dampers, stabilizers, or other parts, and the characteristic identification of each part may require significant costs and time. In this study, the cornering performance of a vehicle system was experimentally evaluated using several combinations of subparts in the suspension module as well as candidate tire cases. All characteristic parameters used in the two indices were previously identified as separate steps, and vehicle tests were performed according to all the required test scenarios for cornering performance. The evaluation of the cornering performance of a vehicle was proposed using the suspension characteristic cornering performance (SCCP) index and suspension and tire characteristic cornering performance based-on-tests (STCT) index, respectively, using measured data from a vehicle test. The STCT index is revised from the SCCP index by considering the tires’ effects, and the optimal selection of the suspension and tires can be obtained from the proposed indices. The feasibility of the proposed STCT index was verified by evaluating the cornering performance from all the prepared test results.
Oil Cavitation Morphology Analysis of Textured Cylindrical Rotating Friction Pair on Circular-Disk End Faces
Authors: Sun Junyu , Chen Liyu , Qian Pengfei , Zhang Bing
Published: November 2022

Cavitation is a destructive hydraulic phenomenon; it causes damage to small hydraulic machinery and large water-conservancy projects, and cavitation and cavitation corrosion problems are long-standing problems for hydraulic machinery experts. Micro-textures are often machined onto the end face near the indirect contact point to increase the oil film bearing capacity and reduce the transfer torque in hydraulic machinery, but the pressure disturbance caused by the texture dimple and boundary can induce cavitation. To delay or eliminate cavitation on the textured surface of equipment such as mechanical seals and dynamic bearings, the cavitation effect of a cylindrical texture on a rotating frictional pair was investigated from theoretical, imitational, and experimental perspectives. Low pressure is extremely important for inducing cavitation; once cavitation conditions are met, a full bubble can be formed in about 0.015 s. Cavitation mainly occurs at the outer radius of the rotating end face, i.e., in the high-speed region. There is a mutual mass transfer between gas and liquid phases when cavitation occurs, but the generation of cavitation bubbles is faster than its collapse, thus causing an increasing cavitation region.
Magnetic Properties and Microstructure of Ce-Cu-Al Low Melting Alloy Bonding Sm2Fe17N3 Magnet Fabricated by the Hot-Pressing Method
Authors: Zheng Jingwu , Yu Shitong , Huang Heng , Li Rongyao , Cai Wei , Chen Haibo , Li Juan , Qiao Liang , Ying Yao , Li Wangchang , Yu Jing , Che Shenglei
Published: November 2022

Sm2Fe17N3 compounds, having excellent intrinsic magnetic properties, are prone to decomposition at high temperatures; thus, a low melting point metal binder is the key to prepare high performance bulk magnets at low temperatures. In this paper, a new low melting point alloy Ce72Cu28-xAlx was used as the binders, and high-performance Ce-based alloy bonding Sm2Fe17N3 magnets were realized by the hot-pressing method. The experimental results demonstrated that the content of Al in the Ce-based alloys had an important influence on the performance of the magnets. High performance Sm-Fe-N bonded magnets with remanence of 10.19 KGs and maximum magnetic energy product of 21.06 MGOe were achieved by using 5 wt.% Ce72Cu22Al6 alloy as a binder. At the same time, it was found that the Ce72Cu28-xAlx alloy has a lower density and better bonding effect than the common Zn binder. Its bonding magnets still have higher performance even with extremely high oxygen content. Therefore, Ce72Cu28-xAlx alloy with low melting point is a promising new rare earth-based alloy binder. If the oxygen content of the alloy powders could be reduced, higher performance Sm2Fe17N3 bonded magnets can be prepared.
Dynamic Tensile Mechanical Properties of Outburst Coal Considering Bedding Effect and Evolution Characteristics of Strain Energy Density
Authors: Gong Shuang , Wang Chaofei , Xi Furui , Jia Yongqiang , Zhou Lei , Zhang Hansong , Wang Jingkuo , Ren Xingyang , Wang Shuai , Yao Shibin , Liu Juan
Published: November 2022

The evolution of strain energy density of outburst-prone coal is of great significance for analyzing the characteristics of energy accumulation and release in coal and rock masses. The dynamic mechanical properties of coal samples were tested by using the split Hopkinson pressure bar (SHPB) technique. Dynamic tensile mechanical properties, layered effect and density evolution characteristics of strain energy for coal were studied. The dynamic failure and crack propagation process of the specimen were recorded with a high-speed camera. In addition, a digital image correlation (DIC) method was used to analyze the evolution characteristics of the strain field during the deformation process of the specimen. The distribution characteristics of the particle fragments were statistically analyzed. The results show that the bedding orientation of the coal has a significant effect on its deformation and damage features. The presence of weak planes, microcracks and laminae causes its shear damage zone to behave more complex. If the crack plane coincides with the high shear stress plane, the developed shear cracks extend along the weak laminae and the shear damage zones in BD specimens are not symmetrically distributed. When the laminated surface of the coal sample is at a certain angle with the impact loading direction, the damage mode is coupled with tensile and shear damage. The percentage mass distribution of particles and fines increases with increasing bedding orientation. The effect of water on the dynamic damage of coal samples is significant. Based on the principle of pressure expansion of wing-shaped cracks, the formula for calculating the dynamic strength of water-saturated coal samples under dynamic loading was derived.
Population-Based Meta-Heuristic Algorithms for Integrated Batch Manufacturing and Delivery Scheduling Problem
Authors: Kim Yong-Jae , Kim Byung-Soo
Published: November 2022

This paper addresses an integrated scheduling problem of batch manufacturing and delivery processes with a single batch machine and direct-shipping trucks. In the manufacturing process, some jobs in the same family are simultaneously processed as a production batch in a single machine. The batch production time depends only on the family type assigned to the production batch and it is dynamically adjusted by batch deterioration and rate-modifying activities. Each job after the batch manufacturing is reassigned to delivery batches. In the delivery process, each delivery batch is directly shipped to the corresponding customer. The delivery time of delivery batches is determined by the distance between the manufacturing site and customer location. The total volume of jobs in each production or delivery batch must not exceed the machine or truck capacity. The objective function is to minimize the total tardiness of jobs delivered to customers with different due dates. To solve the problem, a mixed-integer linear programming model to find the optimal solution for small problem instances is formulated and meta-heuristic algorithms to find effective solutions for large problem instances are presented. Sensitivity analyses are conducted to find the effect of problem parameters on the manufacturing and delivery time.
Regularity for Quasi-Linear p-Laplacian Type Non-Homogeneous Equations in the Heisenberg Group
Authors: Yu Chengwei
Published: November 2022

When 2−1/Q<p≤2, we establish the Cloc0,1 and Cloc1,α-regularities of weak solutions to quasi-linear p-Laplacian type non-homogeneous equations in the Heisenberg group Hn, where Q=2n+2 is the homogeneous dimension of Hn.
Admissible Classes of Multivalent Meromorphic Functions Defined by a Linear Operator
Authors: Ali Ekram E. , El-Ashwah Rabha M. , Albalahi Abeer M. , Breaz Nicoleta
Published: November 2022

The results from this paper are related to the geometric function theory. In order to obtain them, we use the technique based on differential subordination, one of the newest techniques used in the field, also known as the technique of admissible functions. For that, the appropriate classes of admissible functions are first defined. Based on these classes, we obtain some differential subordination and superordination results for multivalent meromorphic functions, analytic in the punctured unit disc, related to a linear operator ℑρ,τp(ν), for τ>0,ν,ρ∈C, such that Re(ρ−ν)≧0, Re(ν)>τp,(p∈N). Moreover, taking into account both subordination and superordination results, we derive a sandwich-type theorem. The connection with some other known results and an example are also provided.
Existence, Uniqueness and Stability Analysis with the Multiple Exp Function Method for NPDEs
Authors: Aderyani Safoura Rezaei , Saadati Reza , O’Regan Donal , Alshammari Fehaid Salem
Published: November 2022

In this study, firstly, through an alternative theorem, we study the existence and uniqueness of solution of some nonlinear PDEs and then investigate the Ulam–Hyers–Rassias stability of solution. Secondly, we apply a relatively novel analytical technique, the multiple exp function method, to obtain the multiple wave solutions of presented nonlinear equations. Finally, we propose the numerical results on tables and discuss the advantages and disadvantages of the method.
Interpretable Deep Learning for Discriminating Pneumonia from Lung Ultrasounds
Authors: Abdel-Basset Mohamed , Hawash Hossam , Alnowibet Khalid Abdulaziz , Mohamed Ali Wagdy , Sallam Karam M.
Published: November 2022

Lung ultrasound images have shown great promise to be an operative point-of-care test for the diagnosis of COVID-19 because of the ease of procedure with negligible individual protection equipment, together with relaxed disinfection. Deep learning (DL) is a robust tool for modeling infection patterns from medical images; however, the existing COVID-19 detection models are complex and thereby are hard to deploy in frequently used mobile platforms in point-of-care testing. Moreover, most of the COVID-19 detection models in the existing literature on DL are implemented as a black box, hence, they are hard to be interpreted or trusted by the healthcare community. This paper presents a novel interpretable DL framework discriminating COVID-19 infection from other cases of pneumonia and normal cases using ultrasound data of patients. In the proposed framework, novel transformer modules are introduced to model the pathological information from ultrasound frames using an improved window-based multi-head self-attention layer. A convolutional patching module is introduced to transform input frames into latent space rather than partitioning input into patches. A weighted pooling module is presented to score the embeddings of the disease representations obtained from the transformer modules to attend to information that is most valuable for the screening decision. Experimental analysis of the public three-class lung ultrasound dataset (PCUS dataset) demonstrates the discriminative power (Accuracy: 93.4%, F1-score: 93.1%, AUC: 97.5%) of the proposed solution overcoming the competing approaches while maintaining low complexity. The proposed model obtained very promising results in comparison with the rival models. More importantly, it gives explainable outputs therefore, it can serve as a candidate tool for empowering the sustainable diagnosis of COVID-19-like diseases in smart healthcare.
Electrodialysis Desalination with Simultaneous pH Adjustment Using Bilayer and Bipolar Membranes, Modeling and Experiment
Authors: Nosova Elena , Achoh Aslan , Zabolotsky Victor , Melnikov Stanislav
Published: November 2022

A kinetic model of the bipolar electrodialysis process with a two-chamber unit cell formed by a bilayer (bipolar or asymmetric bipolar) and cation-exchange membrane is proposed. The model allows describing various processes: pH adjustment of strong electrolyte solutions, the conversion of a salt of a weak acid, pH adjustment of a mixture of strong and weak electrolytes. The model considers the non-ideal selectivity of the bilayer membrane, as well as the competitive transfer of cations (hydrogen and sodium ions) through the cation-exchange membrane. Analytical expressions are obtained that describe the kinetic dependences of pH and concentration of ionic components in the desalination (acidification) compartment for various cases. Comparison of experimental data with calculations results show a good qualitative and, in some cases, quantitative agreement between experimental and calculated data. The model can be used to predict the performance of small bipolar membrane electrodialysis modules designed for pH adjustment processes.
Application of Temperature Cycles to Austenitic Steel and Study of the Residual Stresses Distribution in HAZ
Authors: Bukovská Šárka , Moravec Jaromír , Švec Martin , Sobotka Jiří
Published: November 2022

This paper presents the results of research dealing with assessing the welding effect (temperature–stress cycles) on the residual stresses in these steels. Residual stresses, remaining in the material after technological processing, pose a risk, especially at the areas of local stress peaks. During the real welding, residual stresses achieve their highest values in the heat-affected zone (HAZ), which is very narrow and therefore quite problematic to be studied in detail. Therefore, a methodology of temperature–stress physical simulations has been developed to study residual stresses in the HAZ over a 6.5 times larger section of the test sample. Thus, temperature cycles corresponding to the real welding were applied to the samples in the thermo-mechanical simulator, Gleeble 3500. Subsequently, the residual stresses were determined by the X-ray diffraction method. At the same time, the influence of annealing temperature on the residual stress reduction and redistribution was also investigated. Obtained results were compared and discussed with the similar studies about HSLA and duplex steels.
Experimental and Calphad Methods for Evaluating Residual Stresses and Solid-State Shrinkage after Solidification
Authors: Antikainen Atte , Reijonen Joni , Lagerbom Juha , Lindroos Matti , Pinomaa Tatu , Lindroos Tomi
Published: November 2022

Laser powder bed fusion is an additive manufacturing method that is based on melting and solidification of powder material. Due to the local heating above the melting point, thermal stresses are usually formed in the final part. Mitigation of residual stresses is usually assessed by laser scan strategies and not by alloy tailoring. In this paper a segregation-based residual stress formation mechanism is proposed and assessed computationally. Additionally, an experimental setup for rapid screening of residual stress formation in various alloys is proposed. The results should ease material development of metal alloys tailored for additive manufacturing by allowing the comparison of residual stress formation tendency (e.g., solid state shrinkage) between alloys. The proposed computational method is comparative in nature and forecasting absolute residual stress values would require known temperature dependent elastoplastic properties for the alloys as well as exact thermal history. The proposed experimental method is quantitative but its reliability depends on material properties such as yield strength.
Multi-Compound H2, CH4, and N2 Adsorption Analysis
Authors: Chilev Chavdar , Langlois Patrick , Lamari Farida
Published: November 2022

In order to study the purification of hydrogen and its separation from gas mixtures by adsorption, different models describing the adsorption equilibrium of gas mixtures have been tested; seven of them have been compared with experimental multi-component data obtained from the literature. The measurements include three-component mixtures of hydrogen, nitrogen, and methane. All the models used in this study are purely predictive; such models are competitive isotherm models which use only the previously obtained coefficients of the single-component isotherms. A mathematical description of each model is developed and discussed. Based on the results of numerical experiments, an analysis of how best to apply the Sips multi-component approach and the Ideal Adsorbed Solution theory is developed. A discussion on the ability and accuracy of the different models to describe the multi-component adsorption equilibria is developed. Based on this research, the Jovanovic model, which best reproduces the experimental results of the adsorption equilibrium in all cases, can be recommended as the most appropriate to use.
Simulation and Microstructure Prediction of Resistance Spot Welding of Stainless Steel to Carbon Steel
Authors: Sadeghian Behzad , Taherizadeh Aboozar , Salehi Talieh , Sadeghi Behzad , Cavaliere Pasquale
Published: November 2022

Joining of stainless steel to carbon steel is widely used in various industries. Resistance spot welding (RSW) is a suitable process for joining steel sheets. Due to the complexity and importance of optimizing the parameters, numerical simulation of this process was considered. In this research, the electrical-thermal-mechanical simulation of RSW of 304 stainless steel to St37 carbon steel was performed using finite element method (FEM). Then, the simulated weld nugget size was compared with the experimental results of optical microscopy (OM). In addition, diffusion of metallic elements of the steels in the molten region was simulated using Fick’s equation and compared with experimental results of energy-dispersive X-ray spectroscopy (EDS). It was shown that diffusion of Cr and Ni through the weld nugget, would make a new stainless steel structure. Microstructure prediction of the heat affected zone (HAZ) was performed using Koistinen–Marburger and Leblond–Devaux equations to predict the percentage of martensite and ferrite-perlite phases during the heating and cooling stages of the specimens from room temperature to the peak temperature and cooling down under the Mf temperature. The results of this simulation were validated by scanning electron microscopy (SEM) images and shear tensile and micro-hardness test results. The simulation results showed that increasing the heat input from 1250 A during 0.5 s to 3750 A during 1.5 s, increases the percentage of martensite, from 40% to 80%, in the HAZ and widens the martensite region.
Human Milk from Tandem Feeding Dyads Does Not Differ in Metabolite and Metataxonomic Features When Compared to Single Nursling Dyads under Six Months of Age
Authors: Shenker Natalie S. , Perdones-Montero Alvaro , Burke Adam , Stickland Sarah , McDonald Julie A. K. , Cameron Simon J. S.
Published: November 2022

Given the long-term advantages of exclusive breastfeeding to infants and their mothers, there is both an individual and public health benefit to its promotion and support. Data on the composition of human milk over the course of a full period of lactation for a single nursling is sparse, but data on human milk composition during tandem feeding (feeding children of different ages from different pregnancies) is almost entirely absent. This leaves an important knowledge gap that potentially endangers the ability of parents to make a fully informed choice on infant feeding. We compared the metataxonomic and metabolite fingerprints of human milk samples from 15 tandem feeding dyads to that collected from ten exclusively breastfeeding single nursling dyads where the nursling is under six months of age. Uniquely, our cohort also included three tandem feeding nursling dyads where each child showed a preferential side for feeding—allowing a direct comparison between human milk compositions for different aged nurslings. Across our analysis of volume, total fat, estimation of total microbial load, metabolite fingerprinting, and metataxonomics, we showed no statistically significant differences between tandem feeding and single nursling dyads. This included comparisons of preferential side nurslings of different ages. Together, our findings support the practice of tandem feeding of nurslings, even when feeding an infant under six months.
Revealing the Pathogenesis of Salt-Sensitive Hypertension in Dahl Salt-Sensitive Rats through Integrated Multi-Omics Analysis
Authors: Ou-Yang Ya-nan , Yuan Meng-di , Yang Zheng-mao , Min Zhuo , Jin Yue-xin , Tian Zhong-min
Published: November 2022

Salt-induced renal metabolism dysfunction is an important mechanism of salt-sensitive hypertension. Given that the gut-liver axis is the first hit of a high-salt diet (HSD), we aimed to identify the extra-renal mechanism from hepatic metabolism and gut microbiota, and attempted to relieve the salt-induced metabolic dysfunctions by curcumin. Untargeted metabolomics analysis was performed to identify the changes in hepatic metabolic pathways, and integrated analysis was employed to reveal the relationship between hepatic metabolic dysfunction and gut microbial composition. HSD induced significant increase in fumaric acid, l-lactic acid, creatinine, l-alanine, glycine, and l-cysteine levels, and amino acids metabolism pathways associated with glycolysis were significantly altered, including alanine, aspartate, and glutamate metabolism; glycine, serine, and threonine metabolism, which were involved in the regulation of blood pressure. Integrated multi-omics analysis revealed that changes in Paraprevotella, Erysipelotrichaceae, and genera from Clostridiales are associated with metabolic disorders. Gene functional predication analysis based on 16S Ribosomal RNA sequences showed that the dysfunction in hepatic metabolism were correlated with enhanced lipopolysaccharide (LPS) biosynthesis and apoptosis in gut microbes. Curcumin (50 mg/kg/d) might reduce gut microbes-associated LPS biosynthesis and apoptosis, partially reverse metabolic dysfunction, ameliorate renal oxidative stress, and protect against salt-sensitive hypertension.
Computer Simulations of Silicide-Tetrahedrite Thermoelectric Generators
Authors: Coelho Rodrigo , Casi Álvaro , Araiz Miguel , Astrain David , Branco Lopes Elsa , Brito Francisco P. , Gonçalves António P.
Published: November 2022

With global warming and rising energy demands, it is important now than ever to transit to renewable energy systems. Thermoelectric (TE) devices can present a feasible alternative to generate clean energy from waste heat. However, to become attractive for large-scale applications, such devices must be cheap, efficient, and based on ecofriendly materials. In this study, the potential of novel silicide-tetrahedrite modules for energy generation was examined. Computer simulations based on the finite element method (FEM) and implicit finite difference method (IFDM) were performed. The developed computational models were validated against data measured on a customized system working with commercial TE devices. The models were capable of predicting the TEGs’ behavior with low deviations (≤10%). IFDM was used to study the power produced by the silicide-tetrahedrite TEGs for different ΔT between the sinks, whereas FEM was used to study the temperature distributions across the testing system in detail. To complement these results, the influence of the electrical and thermal contact resistances was evaluated. High thermal resistances were found to affect the devices ΔT up to ~15%, whereas high electrical contact resistances reduced the power output of the silicide-tetrahedrite TEGs by more than ~85%.
Isolation Improvement of Parasitic Element-Loaded Dual-Band MIMO Antenna for Mm-Wave Applications
Authors: Hussain Musa , Awan Wahaj Abbas , Ali Esraa Musa , Alzaidi Mohammed S. , Alsharef Mohammad , Elkamchouchi Dalia H. , Alzahrani Abdullah , Fathy Abo Sree Mohamed
Published: November 2022

A dual-band, compact, high-gain, simple geometry, wideband antenna for 5G millimeter-wave applications at 28 and 38 GHz is proposed in this paper. Initially, an antenna operating over dual bands of 28 and 38 GHz was designed. Later, a four-port Multiple Input Multiple Output (MIMO) antenna was developed for the same dual-band applications for high data rates, low latency, and improved capacity for 5G communication devices. To bring down mutual coupling between antenna elements, a parasitic element of simple geometry was loaded between the MIMO elements. After the insertion of the parasitic element, the isolation of the antenna improved by 25 dB. The suggested creation was designed using a Rogers/Duroid RT-5870 laminate with a thickness of 0.79 mm. The single element proposed has an overall small size of 13 mm × 15 mm, while the MIMO configuration of the proposed work has a miniaturized size of 28 mm × 28 mm. The parasitic element-loaded MIMO antenna offers a high gain of 9.5 and 11.5 dB at resonance frequencies of 28 GHz and 38 GHz, respectively. Various MIMO parameters were also examined, and the results generated by the EM tool CST Studio Suite® and hardware prototype are presented. The parasitic element-loaded MIMO antenna offers an Envelop Correlation Coefficient (ECC) < 0.001 and Channel Capacity Loss (CCL) < 0.01 bps/Hz, which are quite good values. Moreover, a comparison with existing work in the literature is given to show the superiority of the MIMO antenna. The suggested MIMO antenna provides good results and is regarded as a solid candidate for future 5G applications according to the comparison with the state of the art, results, and discussion.
Design and Analysis of a Flexible Smart Apparel MIMO Antenna for Bio-Healthcare Applications
Authors: Govindan Thennarasi , Palaniswamy Sandeep Kumar , Kanagasabai Malathi , Kumar Sachin , Marey Mohamed , Mostafa Hala
Published: November 2022

This paper presents the design and development of a quad-port smart textile antenna for bio-healthcare applications. The antenna is designed to operate in the ultra-wideband (UWB) spectrum (3.1–12 GHz) with an impedance bandwidth of 8.9 GHz. The size of the unit cell and multiple-input multiple-output (MIMO) antenna are 0.25λ0 × 0.2λ0 × 0.015λ0 and 0.52λ0 × 0.52λ0 × 0.015λ0, respectively. The antenna has a maximum efficiency of 93% and a peak gain of 4.62 dBi. The investigation of diversity metrics is performed and the results obtained are found to be ECC < 0.08 and DG < 9.99 dB. The computed CCL and TARC values are <0.13 bits/s/Hz and <−12 dB, respectively. The SAR analysis of the antenna shows a value of 0.471 Watt/Kg at 4 GHz, 0.39 Watt/Kg at 7 GHz, and 0.22 Watt/Kg at 10 GHz.
Animal Models Used in Monkeypox Research
Authors: Domán Marianna , Fehér Enikő , Varga-Kugler Renáta , Jakab Ferenc , Bányai Krisztián
Published: November 2022

Monkeypox is an emerging zoonotic disease with a growing prevalence outside of its endemic area, posing a significant threat to public health. Despite the epidemiological and field investigations of monkeypox, little is known about its maintenance in natural reservoirs, biological implications or disease management. African rodents are considered possible reservoirs, although many mammalian species have been naturally infected with the monkeypox virus (MPXV). The involvement of domestic livestock and pets in spillover events cannot be ruled out, which may facilitate secondary virus transmission to humans. Investigation of MPXV infection in putative reservoir species and non-human primates experimentally uncovered novel findings relevant to the course of pathogenesis, virulence factors and transmission of MPXV that provided valuable information for designing appropriate prevention measures and effective vaccines.
Analysis of Chemical Structure and Antibiofilm Properties of Exopolysaccharides from Lactiplantibacillus plantarum EIR/IF-1 Postbiotics
Authors: Karaca Basar , Haliscelik Ozan , Gursoy Mervi , Kiran Fadime , Loimaranta Vuokko , Söderling Eva , Gursoy Ulvi Kahraman
Published: November 2022

Previous studies have indicated that the exopolysaccharides of lactic acid bacteria exhibit antibiofilm activity against non-oral bacteria by preventing their initial adhesion to surfaces and by downregulating the expression of genes responsible for their biofilm formation. The aims of this study were to (1) characterize the exopolysaccharides (EPSs) of Lactobacillus plantarum EIR/IF-1 postbiotics, (2) test their antibiofilm effect on dual biofilms, and (3) evaluate their bacterial auto-aggregation, co-aggregation, and hydrocarbon-binding inhibitory activity. The EPSs were characterized by FTIR, HPLC, and thermogravimetric analysis. Bacterial auto- and co-aggregation were tested by Kolenbrander’s method and hydrocarbon binding was tested by Rosenberg’s method. Dual biofilms were formed by culturing Fusobacterium nucleatum ATCC 25586 with one of the following bacteria: Prevotella denticola ATCC 33185, P. denticola AHN 33266, Porphyromonas gingivalis ATCC 33277, P. gingivalis AHN 24155, and Filifactor alocis ATCC 35896. The EPSs contained fractions with different molecular weights (51 and 841 kDa) and monosaccharides of glucose, galactose, and fructose. The EPSs showed antibiofilm activity in all the biofilm models tested. The EPSs may have inhibited bacterial aggregation and binding to hydrocarbons by reducing bacterial hydrophobicity. In conclusion, the EPSs of L. plantarum EIR/IF-1, which consists of two major fractions, exhibited antibiofilm activity against oral bacteria, which can be explained by the inhibitory effect of EPSs on the auto-aggregation and co-aggregation of bacteria and their binding to hydrocarbons.
1,4-Naphthoquinone Motif in the Synthesis of New Thiopyrano[2,3-d]thiazoles as Potential Biologically Active Compounds
Authors: Lozynskyi Andrii , Senkiv Julia , Ivasechko Iryna , Finiuk Nataliya , Klyuchivska Olga , Kashchak Nataliya , Lesyk Danylo , Karkhut Andriy , Polovkovych Svyatoslav , Levytska Oksana , Karpenko Olexandr , Boshkayeva Assyl , Sayakova Galiya , Gzella Andrzej , Stoika Rostyslav , Lesyk Roman
Published: November 2022

A series of 11-substituted 3,5,10,11-tetrahydro-2H-benzo[6,7]thiochromeno[2,3-d][1,3]thiazole-2,5,10-triones were obtained via hetero-Diels-Alder reaction of 5-alkyl/arylallylidene/-4-thioxo-2-thiazolidinones and 1,4-naphthoquinones. The structures of newly synthesized compounds were established by spectral data and a single-crystal X-ray diffraction analysis. According to U.S. NCI protocols, compounds 3.5 and 3.6 were screened for their anticancer activity; 11-Phenethyl-3,11-dihydro-2H-benzo[6,7]thiochromeno[2,3-d]thiazole-2,5,10-trione (3.6) showed pronounced cytotoxic effect on leukemia (Jurkat, THP-1), epidermoid (KB3-1, KBC-1), and colon (HCT116wt, HCT116 p53-/-) cell lines. The cytotoxic action of 3.6 on p53-deficient colon carcinoma cells was two times weaker than on HCT116wt, and it may be an interesting feature of the mechanism action.
Small Heterocyclic Ligands as Anticancer Agents: QSAR with a Model G-Quadruplex
Authors: Kaneti Jose , Kurteva Vanya , Georgieva Milena , Krasteva Natalia , Miloshev George , Tabakova Nadezhda , Petkova Zhanina , Bakalova Snezhana M.
Published: November 2022

G-quadruplexes (GQs) have become valid targets for anticancer studies in recent decades due to their multifaceted biological function. Herewith, we aim to quantify interactions of potential heterocyclic ligands (Ls) with model GQs. For seven 4-aminoquinazolines and three 2-heteroaryl perimidines, seven of this ten-membered group so far unknown, we use routine quantum chemical modeling. As shown in the literature, a preferred mode of interaction of heterocycles with cellular structures is stacking to exposable faces of G-quadruplexes. To exploit the energy of this interaction as a molecular descriptor and achieve the necessary chemical precision, we use state of the art large-scale density functional theory (DFT) calculations of stacked heterocycles to a GQ. Actually, the GQ has been simplified for the computation by stripping it off all pentose phosphate residues into a naked model of stacked guanine quartets. The described model thus becomes computable. The obtained heterocyclic ligand GQ.L stacking energies, that is, their GQ affinities, are the necessary ligand descriptors. Using the ligand biological inhibitory activities (IC50) on a human malignant melanoma A375 cell line, we obtain a good linear relationship between computed ligand stacking affinities to GQ, and experimental log (IC50) values. Based on the latter relationship, we discuss a putative mechanism of anticancer activity of heterocyclic ligands via stacking interactions with GQs and thereby controlling cell regulatory activity. This mechanism may tentatively be applied to other condensed five- and six-membered small heterocycles as well.
Recent Development of Nano-Carbon Material in Pharmaceutical Application: A Review
Authors: Jiwanti Prastika K. , Wardhana Brasstira Y. , Sutanto Laurencia G. , Dewi Diva Meisya Maulina , Putri Ilmanda Zalzabhila Danistya , Savitri Ilmi Nur Indira
Published: November 2022

Carbon nanomaterials have attracted researchers in pharmaceutical applications due to their outstanding properties and flexible dimensional structures. Carbon nanomaterials (CNMs) have electrical properties, high thermal surface area, and high cellular internalization, making them suitable for drug and gene delivery, antioxidants, bioimaging, biosensing, and tissue engineering applications. There are various types of carbon nanomaterials including graphene, carbon nanotubes, fullerenes, nanodiamond, quantum dots and many more that have interesting applications in the future. The functionalization of the carbon nanomaterial surface could modify its chemical and physical properties, as well as improve drug loading capacity, biocompatibility, suppress immune response and have the ability to direct drug delivery to the targeted site. Carbon nanomaterials could also be fabricated into composites with proteins and drugs to reduce toxicity and increase effectiveness in the pharmaceutical field. Thus, carbon nanomaterials are very effective for applications in pharmaceutical or biomedical systems. This review will demonstrate the extraordinary properties of nanocarbon materials that can be used in pharmaceutical applications.