bluuebunny/crossref_metadata_2025 huggingface dataset:
Volumetric growth of a composite thick-walled elastic cylinder
Authors: Нестеров Тимофей Константинович , Мурашкин Евгений Валерьевич
Published: January 2022

В данной работе представлено решение задачи наращивания тела цилиндрической формы. Рассмотрен процесс объемного роста в области наращивания. Решение задачи строится в рамках модели малых упругих деформаций. В рассмотрение введены три конфигурации деформируемого тела: естественная, виртуальная, актуальная. Вычислены распределения перемещений и напряжений возникающих в процессе роста.

This paper presents a solution to the problem of growing a cylindrical solids. The process of volumetric growth in the extension area is considered. The solution of the problem is obtained within the framework of the model of small elastic deformations. Three configurations of a solid are introduced into consideration: natural, virtual, actual. The distributions of displacements and stresses during the process of growth are calculated.
Characteristics of Turbulence Driven by Transient Magnetic Reconnection in the Terrestrial Magnetotail
Authors: Jin Runqing , Zhou Meng , Pang Ye , Deng Xiaohua , Yi Yongyuan
Published: January 2022

This paper investigates the evolution of turbulence within the magnetotail reconnection exhaust observed by the Magnetospheric Multiscale spacecraft. The reconnection was in an unsteady state that caused significant temporal variations in the outflow speed. By dividing the exhaust into nine fast flows, we analyzed and compared the characteristics of turbulence in these nine flows. We find that the strength of the intermittency has a good relationship with the peak speed of the fast flows. The higher-order analysis of magnetic field fluctuations reveals that the turbulence is multifractal in the inertial range for these flows except one with the highest peak speed. Moreover, the turbulence is monofractal on kinetic scales in all of these fast flows. The magnetic energy was intermittently dissipated in these turbulent flows, predominantly occurred in the coherent structures. Since the coherent structures with the largest energy dissipation in these flows are different, we suggest that the mechanism of energy dissipation may be different among these flows.
Magnetic Fields in Star Formation: A Complete Compilation of All the DCF Estimations
Authors: Liu 刘 Junhao 峻豪 , Qiu Keping , Zhang Qizhou
Published: January 2022

The Davis–Chandrasekhar–Fermi (DCF) method provides an indirect way to estimate the magnetic field strength from statistics of magnetic field orientations. We compile all the previous DCF estimations from polarized dust emission observations and recalculate the magnetic field strength of the selected samples with the new DCF correction factors in Liu et al. We find the magnetic field scales with the volume density as B ∝ n
0.57. However, the estimated power-law index of the observed B–n relation has large uncertainties and may not be comparable to the B–n relation of theoretical models. A clear trend of decreasing magnetic viral parameter (i.e., increasing mass-to-flux ratio in units of critical value) with increasing column density is found in the sample, which suggests the magnetic field dominates the gravity at lower densities but cannot compete with the gravity at higher densities. This finding also indicates that the magnetic flux is dissipated at higher column densities due to ambipolar diffusion or magnetic reconnection, and the accumulation of mass at higher densities may be by mass flows along the magnetic field lines. Both sub-Alfvénic and super-Alfvénic states are found in the sample, with the average state being approximately trans-Alfvénic.
Effects of the ϕ Meson on the Properties of Hyperon Stars in the Density-dependent Relativistic Mean Field Model
Authors: Tu Zhong-Hao , Zhou Shan-Gui
Published: January 2022

The effects of the ϕ meson on the properties of hyperon stars are studied systematically in the framework of the density-dependent relativistic mean field (DDRMF) model. The ϕ meson shifts the hyperon threshold to a higher density and reduces the hyperon fractions in neutron star cores. It also strongly stiffens the equation of state calculated with various DDRMF effective interactions and increases the maximum mass of hyperon stars, but only a few effective interactions survive under the constraints from recent astrophysical observations. In the DDRMF model, the conformal limit of the sound velocity is still in strong tension with the fact that the maximum mass of neutron stars obtained in theoretical calculations reaches about 2 M
⊙. Based on different interior composition assumptions, we discuss the possibility of the secondary object of GW190814 as a neutron star. When the ϕ meson is considered, DD-ME2 and DD-MEX support the possibility that the secondary object of GW190814 is a hyperon star rapidly rotating with Kepler frequency.
Renovascular Hypertension in Chronic Hemodialytic Patient
Authors: Lestari Sri , Prasanto Heru , Kuswadi Iri
Published: January 2022

Background: Hypertension is a major contributor to the development of chronic kidney disease. Data in Indonesia, hypertension is still the most comorbid disease in CKD patients on dialysis (51%). Hypertension in CKD on dialysis patients is common and often uncontrolled.  Renovascular hypertension is the most common cause of secondary hypertension. Diagnosis and treatment of RAS is very important, because it can accelerate the achievement of blood pressure targets, reduce the risk and complications due to hypertension.
Case Report: A 52-year-old woman with CKD has been undergoing hemodialysis for 2 years. Hypertension that was previously well controlled for 2 years required an increase in antihypertensive therapy from 2 to 4 drugs in recent months. On physical examination the blood pressure 180/90 mmHg, pulse 79 bpm, respiration 20/min, temperature 36.7oC. Conjunctiva looks anemic, cardiomegaly, lungs within normal limits, no ascites and edema in the extremities. On renal artery duplex ultrasound examination, right main renal artery acceleration time 147.65 ms, Peak Systolic Velocity (PSV) 31.9 cm/s. RI 0.69 and left main renal artery acceleration time 120.81 ms, PSV 16.9 cm/s, RI 0.61. There was 20-30% left renal artery stenosis, 80% right renal artery stenosis. A stent was placed on the right renal artery. The patient's condition after PTRA improved, but at the next follow-up, mean systole and diastole 170 mmHg and 80 mmHg, respectively. Patient received 4 antihypertensive therapy.
Conclusion: Renal artery stenosis is a disease that consists of a broad spectrum of different entities with different pathophysiologies that require varied approaches to diagnose and treat. Current diagnostic tools include MRA, CTA and renal artery duplex ultrasonography. Patients with renal parenchymal disease are poorer candidates for revascularization.
Complete Molar Pregnancy in Postmenopausal Woman: A Rare Case Report
Authors: Sutrisno Sutrisno , Farida Leny , Defri Defri
Published: January 2022

BACKGROUND: Molar pregnancy, the form of the gestational trophoblastic disease (GTD), generally occurs in women of the reproductive age group, and rarely occurs in postmenopausal women. To present a rare case of molar pregnancy in a postmenopausal woman.

CASE REPORT: A multiparous woman aged 54 years was referred to the outpatient department at Raja Ahmad Tabib General Hospital of Riau Island, Indonesia with the main symptoms of nausea and vomiting profusely with 1 month before, lower abdominal pain, lump in the abdomen, abnormal vaginal bleeding, and a positive urine pregnancy test. Her last menstrual bleeding was 14 months ago. Physical examination found stable hemodynamic within blood pressure 150/95 mmHg. Laboratory results showed Hb 11.7 g/dL, positive urine pregnancy test, and serum β-HCG 292,876.1 mIU/mL. Ultrasound examination showed a vesicular pattern in the uterine cavity without fetal tissue. The patient was managed by elective total abdominal bilateral hysterectomy salpingo-oophorectomy. The intraoperative finding was softened, enlarged uterus size of 14–16 weeks of pregnancy, and no local spreading of disease. The patient was discharged on the 3 day after surgery.

CONCLUSION: Even though molar pregnancy is rare, it can occur in the postmenopausal woman. Therefore, GTD has remained in the differential diagnosis of postmenopausal bleeding which can prevent delay in diagnosis and management. Definitive treatment with total abdominal hysterectomy has been chosen in menopausal women who do not wish to preserve their fertility and prevent any malignant sequelae.
Predictive Score Model of Clinical Outcomes Sepsis in Intensive Care Unit Tertier Referral Hospital of Eastern Indonesia
Authors: Octora Metta , Mertaniasih Ni Made , Semedi Bambang Pujo , Koendhori Eko Budi
Published: January 2022

AIM: This study aimed to design a predictive score model of clinical outcome sepsis and bacterial profiles of blood and sputum cultures in the intensive care unit (ICU) of a tertiary referral hospital.

METHODS: An observational retrospective study was conducted in 2017–2020 using medical record data in the ICU of Dr. Soetomo Hospital as tertiary referral hospital. The predictor of sepsis prognosis was Acute Physiology and Chronic Health Evaluation II (APACHE II), blood and sputum culture results, procalcitonin (PCT) levels, and antimicrobial resistance in blood and sputum cultures. The model was prepared by logistic regression analysis and receiver operating characteristic (ROC) curves.

RESULTS: Data from 355 subjects showed that predictor score was APACHE II, blood and sputum culture results; besides PCT levels were found to contribute significantly to predictive score of sepsis clinical output (p<0.05), while the predictor test of antimicrobial resistance in blood and sputum cultures was not significant to predictive score of sepsis clinical output (p > 0.05). The resulting scores to predict sepsis clinical outcomes include PCT level >2 ng/mL (1.61), APACHE score >20 (1), sputum culture as true pathogen (1.1), and blood culture as true pathogen (1.35). When the total score ≥3, the patient will die, while when the score <3, the patient will survive. ROC curves analysis obtained area under curve 0.859 (p < 0.05) which indicates that the equation is statistically significant in predicting the sepsis clinical outcome. Probability scores and death outcomes indicate that the higher the predictive score, the higher the probability of dying, with a score >3 the probability of dying is above 95.27%, whereas if the score is 5, the probability of dying is above 99%. The bacterial profile of blood cultures leading to mortality is predominately Gram-positive (34.4%), consisting of coagulase-negative Staphylococcus (22.9%), and Staphylococcus aureus (4.3%), while Gram-negative is only 14.7%, which consists of Enterobacteriaceae group (8.7%), Acinetobacter baumannii (4%), polymicrobial infection (2%), Burkholderia cepacia (0.8%), and Pseudomonas aeruginosa (0.4%). Sputum culture profile of patients with sepsis who died in the ICU of a tertiary referral RSUD Soetomo is dominated by Gram-negative, namely, A. baumannii (22.1%), Enterobacteriaceae group (20.6%), P. aeruginosa (11.1%), while Gram-positive is S. aureus (22.9%).

CONCLUSION: The predictive score model for sepsis clinical outcomes in the ICU of a tertiary referral hospitals can be used as a basis for determining of patient management and the profile of the bacteria that causes sepsis that results in death.
Violences, délinquances : quelles caractéristiques dans les quartiers populaires ?
Authors: Berlioz Gilbert , Bourgeois Frédérique
Published: January 2022

Rodéos, voitures brûlées, trafic de stupéfiants, affrontements avec les forces de l’ordre… autant de faits délictueux associés aux quartiers populaires, comme une réputation indélébile dont les origines remonteraient à l’été 1981, avec les émeutes urbaines des Minguettes, à Vénissieux. Quarante années après, quelle est la situation dans les quartiers ? Quelles sont les manifestations de la violence et de la délinquance dans ces territoires ?
La tranquillité pour tous : une priorité à Clermont-Ferrand
Authors: Bourgeois Frédérique
Published: January 2022

Une stratégie, des outils et des partenaires… tels sont les ingrédients pour prévenir et lutter contre la délinquance et participer à la tranquillité publique. Explication de texte avec Jérôme Godard, adjoint à la tranquillité publique, prévention de la délinquance et protection des populations à la Ville de Clermont-Ferrand.
Coordonnateurs de CLSPD : des femmes et des hommes de l’ombre
Authors: Bourgeois Frédérique , Fromentin Marjorie
Published: January 2022

Les coordonnateurs de CLSPD tiennent une place centrale dans la prévention de la délinquance au quotidien. Ces postes aux tâches hétérogènes sont pourtant mal connus et insuffisamment reconnus sur le plan institutionnel. Afin de comprendre la diversité et la complexité de ces métiers, Labo Cités a organisé une table ronde en octobre 2021 rassemblant quatre coordonnateurs aux profils, trajectoires et territoires différents. Retrouvez dans cet article leurs analyses et témoignages, entre enthousiasme et inquiétudes.
La prévention de la délinquance : quelle place dans les parcours de formation ?
Authors: Bourgeois Frédérique
Published: January 2022

Que l’on se situe du côté des policiers municipaux ou des travailleurs sociaux, comment la formation prend-elle en compte la prévention de la délinquance et le travail en partenariat ? Regards croisés entre Éric Irles, conseiller formation à la délégation Auvergne-Rhône-Alpes du CNFPT (Centre national de la fonction publique territoriale), et Daniel Lepecq, formateur à l’ENSEIS d’Annecy (École nationale des solidarités, de l’encadrement et de l’intervention sociale).
Les bailleurs sociaux face aux défis de la tranquillité-sûreté résidentielle
Authors: Obled Marie-Claire
Published: January 2022

Incivilités, actes de délinquance à répétition… les moyens mis en œuvre par les bailleurs sociaux ne suffisent plus et rendent nécessaire le partenariat avec les différentes instances publiques. Marie-Claire Obled, chargée de projet territorial Puy-de-Dôme à l’Aura HLM 1 , nous présente le projet Actéo, dispositif mutualisé et partenarial de tranquillité résidentielle et présence de soirée sur les quartiers NPNRU 2 de la métropole clermontoise.
Itinérances allemandes de Molière : l’exemple de la Berühmte Bande des Velten
Authors: Gross Martina
Published: January 2022

Lorsque l’on considère la première réception de Molière dans le monde germanophone, l’accent est principalement mis sur les traductions. Elles font partie des efforts visant à créer une culture nationale et sont par conséquent bien exploitées. Cependant cette première réception des pièces de Molière en Allemagne se déroule bien avant Gottsched et Lessing et précède le développement de leurs théories en faveur d’un théâtre national. Afin de révéler la transnationalité ou plutôt la transculturalité de la pratique théâtrale autour de 1700, cet article se focalisera sur les représentations de ces pièces données à cette époque par les troupes itinérantes.
Molière avant Molière ? La première réception du corpus moliéresque en Russie
Authors: Evstratov Alexeï
Published: January 2022

La figure de Molière occupe dans l’histoire des spectacles en Russie une place de choix qu’on a souvent étudiée dans le cadre du paradigme d’influence. Sceptique à l’égard de cette notion, cette contribution s’intéresse aux traces concrètes de la circulation du corpus moliéresque au début du xviii e  siècle. Quelles étaient les sources des traductions conservées ? est-ce que ces pièces ont été effectivement représentées ? Les exemples des trois titres –  Le Médecin malgré lui , Les Précieuses ridicules et Amphitryon  – illustrent les problèmes philologiques posés par le corpus.
Cathos et Madelon entre terres et mers portugaises au XVIII e siècle
Authors: Ciccia Marie-Noëlle
Published: January 2022

La divulgation du théâtre de Molière débute au Portugal au xviii e  siècle, dans des versions « adaptées au goût portugais ». La comédie des Précieuses ridicules , dont le langage précieux est affadi par une traduction médiocre, est réduite à un entremez de 16 pages. Elle a connu deux éditions au xviii e  siècle, preuve que les Cathos et Madelon portugaises trouvaient un écho dans une société où existaient les peraltas , des dandies des deux sexes. Par le prisme de la fortune de cette petite comédie, on peut mesurer l’intérêt porté à la présence de Molière à Lisbonne dès 1768 ainsi qu’au Brésil.
The influence of the physical coefficients of a Bresse system with one singular local viscous damping in the longitudinal displacement on its stabilization
Authors: Akil Mohammad , Badawi Haidar
Published: January 2022

In this paper, we investigate the stabilization of a linear Bresse system with one singular local frictional damping acting in the longitudinal displacement, under fully Dirichlet boundary conditions. First, we prove the strong stability of our system. Next, using a frequency domain approach combined with the multiplier method, we establish the exponential stability of the solution if the three waves have the same speed of propagation. On the contrary, we prove that the energy of our system decays polynomially with rates \begin{document}$ t^{-1} $\end{document} or \begin{document}$ t^{-\frac{1}{2}} $\end{document}.
Optimal financing strategy in a closed-loop supply chain for construction machinery remanufacturing with emissions abatement
Authors: Fu Shuaishuai , Chen Weida , Ding Junfei , Wang Dandan
Published: January 2022

Motivated by the remanufacturing practice of construction machinery, this paper examines the impacts of different cooperation financing and carbon emission reduction (CER) strategies on the operational decisions in a closed-loop supply chain (CLSC) where the original equipment manufacturer (OEM) produces only new products and the capital-constraint retailer produces remanufactured products and sells both new and remanufactured products to consumers. Based on the cooperation level between the OEM and the retailer, four different financing strategies, including the non-cooperation financing (NCF), the supply chain carbon financing (SCCF), the partial cooperation with delay-in-payment financing (PCD), and the full-cooperation financing (FC), are explored. Meanwhile, we extend the proposed models by considering the CER strategy implemented by the OEM, and then investigate its impact on the optimal operational and financing decisions of the retailer. The results show that: i) Under different financing strategies, the CER strategy has no impact on the retail price of remanufactured products, but can help increase the market share of new products and strengthen the market value effect for the OEM. ii) Compared with the scenario without CER, the SCCF strategy can not only ease funding pressure than the NCF strategy for the retailer but also increase the CLSC profit under the CER strategy. iii) No matter which financing strategy is adopted, the CER strategy always has a squeezing effect on the market size of remanufactured products, i.e., the cannibalization effect. iv) The CER strategy is not conducive to the development of the remanufacturing industry, but can improve the environmental performance in terms of reducing emissions and increasing the market sales for new products.
On the concentration–compactness principle for Folland–Stein spaces and for fractional horizontal Sobolev spaces
Authors: Pucci Patrizia ,   Dipartimento di Matematica e Informatica, Università degli Studi di Perugia, Via Vanvitelli 1, 06123 Perugia, Italy, Temperini Letizia ,   Dipartimento di Matematica e Informatica 'Ulisse Dini', Università degli Studi di Firenze, Viale Morgagni 67/a, 50134 Firenze, Italy
Published: January 2022

In this paper we establish some variants of the celebrated concentration–compactness principle of Lions – CC principle briefly – in the classical and fractional Folland–Stein spaces. In the first part of the paper, following the main ideas of the pioneering papers of Lions, we prove the CC principle and its variant, that is the CC principle at infinity of Chabrowski, in the classical Folland–Stein space, involving the Hardy–Sobolev embedding in the Heisenberg setting. In the second part, we extend the method to the fractional Folland–Stein space. The results proved here will be exploited in a forthcoming paper to obtain existence of solutions for local and nonlocal subelliptic equations in the Heisenberg group, involving critical nonlinearities and Hardy terms. Indeed, in this type of problems a triple loss of compactness occurs and the issue of finding solutions is deeply connected to the concentration phenomena taking place when considering sequences of approximated solutions.
Media Competition and Social Disagreement
Authors: Perego Jacopo , Yuksel Sevgi
Published: January 2022

We study the competitive provision and endogenous acquisition of political information. Our main result identifies a natural equilibrium channel through which a more competitive market decreases the efficiency of policy outcomes. A critical insight we put forward is that competition among information providers leads to informational specialization: firms provide relatively less information on issues that are of common interest and relatively more information on issues on which agents' preferences are heterogeneous. This enables agents to acquire information about different aspects of the policy, specifically, those that are particularly important to them. This leads to an increase in social disagreement, which has negative welfare implications. We establish that, in large enough societies, competition makes every agent worse off by decreasing the utility that she derives from the policy outcome. Furthermore, we show that this decline cannot be compensated by the decrease in prices resulting from competition.
Modeling time varying risk of natural resource assets: Implications of climate change
Authors: Leroux Anke D. , Martin Vance L. , St. John Kathryn A.
Published: January 2022

A multivariate GARCH model of natural resources is specified to capture the effects of time varying portfolio risk. A special feature of the model is the inclusion of realized volatility for natural resource assets that are available at multiple frequencies as well as being sensitive to sudden changes in climatic conditions. Natural resource portfolios under climate change are simulated from bootstrapping schemes as well as being derived from global climate model projections. Both approaches are applied to a multiasset water portfolio model consisting of reservoir inflows, rainwater harvesting, and desalinated water. The empirical results show that while reservoirs remain the dominant water asset, adaptation to climate change involves increased contributions from rainwater harvesting and more frequent use of desalinated water. It is estimated that climate change increases annual water supply costs by between 7% and 44% over a 20‐year forecast horizon.
Having the private sector build social housing
Authors: Bernard Nicolas , Traversa Edoardo
Published: January 2022

La Région bruxelloise manque dramatiquement de logements sociaux, on le sait. Si le régime de la TVA avantage incontestablement la production publique des logements sociaux (par l’octroi d’un taux réduit : 6 %), il n’aide en rien les opérateurs privés ni les associations qui, pareillement, ont pour vocation de mettre à disposition des logements à un tarif modeste (sans passer par une agence immobilière sociale).  En plus, ce système différencié de TVA heurte deux principes juridiques fondamentaux : l’égalité de traitement et la neutralité fiscale (suivant lequel deux opérations semblables quant à leurs résultats doivent connaître un régime fiscal lui-même semblable). Il est temps dès lors de changer ce logiciel fiscal. Mais que peut bien faire la Région bruxelloise dès lors que cet impôt relève des compétences de l’autorité fédérale ? Deux choses au moins : englober dans la catégorie de « société de logement » (qui bénéficie déjà du taux de TVA réduit) la construction privée de logements à caractère social ou, à défaut, accorder à cette dernière activité un subside qui compenserait la différence entre le taux standard de TVA (qui sera appliqué) et le taux réduit. Le tout, naturellement, moyennant une série de contreparties sociales, comme vendre une certaine proportion des biens ainsi produits à une société de logement social et assujettir à certaines conditions sociales la vente (ou la location) du solde. En impliquant de la sorte le secteur privé, il sera permis d’espérer une résorption plus rapide de la très longue file d’attente des logements sociaux.
Employee Attitudes Towards Ubiquitous Library-Supported Professional Learning
Authors: Chen Chun-Kuei , Kuo Yen-Ku , Tu Yun-Fang , Hwang Gwo-Jen
Published: January 2022

This study aimed to explore the influencing factors of employees’ attitudes towards ubiquitous library-supported professional learning (AULPL) when they adopted the ubiquitous library in the workplace. A total of 164 valid questionnaires were collected and analyzed to examine the effects of the employees’ job characteristics and self-regulated learning on their attitudes towards ubiquitous library-supported professional learning. The results indicate that the employees’ job characteristics (i.e., job control and social support) and self-regulated learning can predict their attitudes towards ubiquitous library-supported professional learning. In addition, self-regulated learning acted as a mediator between job characteristics and AULPL. Basic self-regulated learning mediates the relationships between job control in job characteristics and perceived usefulness for AULPL. Advanced self-regulated learning mediates the relationship between job control in job characteristics and AULPL (i.e., perceived usefulness, perceived ease of use, affection, behavior).
Estimation of Durability Benchmark on Concrete Samples Using Artificial Intelligence
Authors: Guzmán-Torres José Alberto
Published: January 2022

This paper proposes a deep learning model for predicting the durability benchmark on concrete specimens. The durability benchmark on concrete samples is commonly estimated throughout the Ultrasonic Pulse Velocity measurements. This test establishes a relationship with concrete durability taken into consideration the material's homogeneity. The model proposed in this paper is feed by standard laboratory tests as input parameters, making the model a practical and efficient alternative to predict durability concrete benchmark, saving time, short-cut laboratory work, and avoiding sophisticated instrumentation use. Furthermore, it is an attractive alternative to the need for sophisticated instrumentation for estimating the Ultrasonic Pulse Velocity. The outcomes depict a high predictive accuracy about of 96% in the validation stage. In addition, the model was tested by a new dataset with different properties to demonstrate robustness and certainty in the model. Finally, the model achieves an impressive accuracy of 95.89% in the new validation dataset.
Protecting the Hull of High-Speed Crafts against Slamming Loads Using Hybrid Viscoelastic Layers
Authors: Townsend Patrick , Suárez Juan Carlos , Rodríguez-Ortìz Alvaro , Muñoz Nadia
Published: January 2022

A finite element model of a small, high-speed glass fiber-reinforced polymer (GFRP) craft is presented to simulate the impact of slamming on the bottom of the hull. The behavior patterns of the model are based on the results of laboratory experiments in order to verify the use of a viscoelastic sheet in absorbing the energy of impact damage by modifying the laminate of the hull. The stacking sequence for the model is obtained using a sample from a typical ship sailing in the Galapagos Islands. The FEM model shows the variations in energy absorption by comparing them with strain and damage–strain energy. The benefits of the viscoelastic modification are verified, and its use is proposed for the construction and modification of ships that support destructive slamming loads.
Examination of Toughening Mechanisms of Zirconia Fabricated by Spark Plasma Sintering Methods
Authors: Sudo Keita , Kudo Tomoo , Tsukamoto Hideaki
Published: January 2022

Ceramics/ metal functionally graded materials (FGMs) have been attracting much attention as composite materials that are intended for application to high-temperature structures. This study fucuses on toughening of ceramics and their matrix composites, which are building blocks of the FGMs. Partially stabilized zirconia (PSZ) with toughening additives such as Ni particles, Inconel fibers, SiC particles, SiC whiskers and a-alumina (Al2O3) particles were fabricated by spark plasma sintering (SPS). Toughening mechanisms were investigated based on their micro and macro-scale mechanical properties and microstructures. Disk bending tests, producing balanced biaxial loading conditions, were conducted probing bending strength at macro scales, while Vickers hardness tests were carried out to estimate fracture toughness and examine toughening mechanisms at micro scales. The results demonstrated that toughness of ZrO2 increased by adding Ni particles, Inconel fibers and Al2O3 particles. Addition of Al2O3 particles highly enhanced disk bending strength and deformability.
Fabrication of Metal Matrix Composites with Thermally Unstable Reinforcements by Spark Plasma Sintering
Authors: Watanabe Yoshimi , Shrikrishna Yadav Manasi , Sato Hisashi
Published: January 2022

Spark plasma sintering can be carried out at a low temperature with short heating, holding and cooling times, which allows for the fabrication of non-equilibrium materials. In this article, metal-matrix-composite fabrication with thermally unstable reinforcements by spark plasma sintering is described.
Processing Biodegradable Fused Filament Fabrication Waste with Micro-Silica Particles
Authors: Siraj Sidra , Al-Marzouqi Ali H. , Ahmed Waleed
Published: January 2022

Microparticles of sand silica have been mixed with biodegradable waste (polylactic acid) from the fused filament fabrication process to investigate the impact on the mechanical properties. The composite mixtures were prepared using different compositions via a twin extrusion machine. Mechanical characterization using the Tensile Testing Machine was performed. The peak strength values indicated that increasing silica composition increased the tensile strength from 62.8 MPa at 0 wt% to 121.03 MPa at 10 wt%. However, a drop was observed beyond this point. It was concluded that for the yield strength, toughness, and failure strain, a similar trend was observed, and the values of the material increased up to 10 wt%, which corresponds to the increased mechanical property of the mixtures with reinforcement of silica microparticles. It is demonstrated that the mechanical properties have been improved for the processed material attributing to the impact of the recycling process of the polylactic acid from leftover 3D printing waste and promoting its potential reuse in the same application.
Waterborne Polyurethanes for Electrical Applications as Insulators and Anti-Electrostatic
Authors: Marín-Genescà Marc , Garcia-Amoros Jordi
Published: January 2022

In this manuscript, we analyze the viability of waterborne polyurethanes (WPU) and compounds derived from WPU mixtures, for applications of these materials in the electrical, electronic, and energy fields as insulation and anti-electrostatic applications. In the current research, several applications type of neat WPU, with any reinforcement, and WPU polymer blends have been studied and compared with standard criterions from the International Electrotechnical Commission (IEC) and Standardization Association from Spain (UNE). To analyze the feasibility in different industrial applications selected, certain compounds obtained from the WPU blends were analyzed regarding their use in eleven low requirement insulator and anti-electrostatic applications. The research and analysis developed in this manuscript used standard data from the UNE – IEC norms, and these standard values were compared with the obtained research values from scientific literature and recent research published experiences. The obtained results were used to provide an application list that could be helpful for industrial applications. In this research, the analyzed WPU compounds neat WPU, Fe3O4 WPU composites, among other nanocomposites WPU blends, which has been currently published in research works, journals, and conferences. We have discovered some possible useful applications for WPU with any reinforcement, mainly as insulators and for WPU nanocomposite blends for anti-electrostatic uses, mainly dielectric and mechanical features compared, however other test types are needed to obtain like flame resistance, thermal behavior, or another key aspect to analyze in deep.
A Review on Dissolvable Alloys - Part I: Development of Materials
Authors: Xu Jian Hui , Zhan Guo Dong , Aljohar Abdulwahab S. , Moellendick Timothy Eric
Published: January 2022

In the trend of unconventional oil and gas explorations, the long laterals over 3,000 m are commonly fractured in multistage fracturing operations. The mill-out of the conventional and temporary isolation downhole tools, such as frac plugs or balls/ball seats, in these wells using mechanical intervention, such as coiled tubing (CT), is a challenge. This paper is to review the developments of the dissolvable alloys to be used on these tools in these long lateral wells to eliminate the mechanical intervention afterward. It includes the history and current status of the developments of the dissolvable alloys. The two types of mainstream dissolvable alloys including magnesium-based and aluminum-based alloys were developed, based on their microscale galvanic corrosion behaviors. The properties of these dissolvable alloys, therefore, depend on the chemistry, process and finally microstructure. The casting and extrusion processes will be discussed since they are very important processes to enhance properties of the dissolvable alloys. The properties including the strength, the ductility and the dissolvability are measured under various temperatures, pressures and salinities conditions. The future trend of development is also briefly visioned.
Photo Effect Studies in Graphene/N-GaAs Schottky Junction Using NEGF Method for Photovoltaic Application
Authors: Khan Md Azmot Ullah , Adesina Naheem Olakunle , Xu Jian
Published: January 2022

In this paper, we present the photovoltaic characteristics of nanoscale Schottky junction solar cell consisting of graphene and GaAs using numerical simulation based on non-equilibrium Green’s function formalism. In our model, light-matter interaction is formulated by the coupling and scattering self-energy matrices whereas heterostructure is designed with a Hamiltonian matrix. An efficiency of 2.36% is obtained for monolayer graphene on GaAs; the efficiency is later enhanced to 5.40% by increasing both the number of graphene layers and the doping concentration of GaAs. The parameters to calculate power conversion efficiency, series and shunt resistances are extracted from the J-V characteristic. The I-V characteristic is also numerically simulated to extract reverse saturation current, ideality factor, and rectification ratio. Moreover, the power density is calculated for the optimized structure; the maximum power density of 7.46 mW/cm2 is obtained for four layers of graphene and a doping concentration of 1017/cm3 in GaAs.
High Throughput Calculation and Characteristic Structure Selection of Cu-Cr-Sn Copper Alloy Based on Matclould Platform
Authors: Tang Jin Jun , Liang Cui , Xu Chen Guang
Published: January 2022

In this paper, high-throughput crystal structure modeling and high-throughput screening optimization algorithm are used to optimize the performance parameters such as characteristic microstructure type, generation conditions, strength and conductivity. The theoretical criterion of multi parameter collaborative optimization and control of key properties of matrix and second phase is established, based on which the optimal composition range of matrix and second phase is determined, which guides high-throughput experimental verification and material screening, and provides basic data for material composition design and structure control. Realize 102 secondary high-throughput parallel computing and screening based on matcloud platform, and calculate and screen the number of candidate material samples ≧106 and other related technologies. Through the functions of online generation, submission and job monitoring of first principle high-throughput jobs, all computing processes are realized automatically, and the computing results are extracted, standardized processed and stored in the database according to certain rules. In this project, the prediction model and process design platform of material composition structure process performance relationship are established according to the dynamic selection parameters of copper alloy structure, pseudopotential recommendation, k-point file generated according to calculation tasks and structure, and the correlation of some other main parameters.
Impact Behavior of High-Strength Engineered Cementitious Composite and Concrete Layered Slabs
Authors: Wu Chao , Mohammed Mostafa M. , Wang Yong , Hou Chuan Chuan
Published: January 2022

High strength Engineered Cementitious Composite (HS-ECC) is a promising material to be used in protective structures. Due to its high manufacturing efforts and cost compared to conventional concrete, nonlinear finite element (FE) simulation is performed to study the influence of replacing HS-ECC layers with concrete under drop weight impact load. Both materials are simulated using the MAT_72R3 material model impeded in LS-DYNA and verified with experimental results. Several FE slab models were developed to compare the impact responses of different configurations. This study as a whole will provide a guideline for researchers to carry out a performance and cost optimization for protective structure elements.
Analysis and Optimization of Forming Quality of 3D Concrete Printing Materials
Authors: Liu Shi Ping , Ma Zi Yan , Xia Wen Jie , Huang Yuan Jing
Published: January 2022

3D concrete printing is a kind of construction method that takes concrete as processing material for extrusion forming. The material properties of concrete make it difficult to control the dimensional accuracy of printed parts, so there are always problems in forming quality of concrete printed parts. In this paper, the error sources of concrete printed parts are discussed firstly, and the forming quality of the printed parts material is analyzed in combination with GD&T system and concrete structure engineering construction quality acceptance specifications. Then, the factors affecting the forming quality are summarized. Finally, the optimization and improvement methods are proposed.
Reversible Poly Lactic Acid (PLA) Film for Volatile Organic Compounds (VOCs) Gas Sensor
Authors: Alias Siti Amirah , Ishak Ku Marsilla Ku
Published: January 2022

The detection of volatile organic compounds (VOCs) including hydrochloric acid (HCl), acetic acid (CH3COOH), and ammonia (NH3) in indoor air is crucial due to human health safety. In this study, halochromic poly lactic acid (PLA) film sensor were prepared. PLA film were fabricated by addition of polyethylene glycol (PEG) and bromocresol purple (BCP) into PLA using solution casting method. Visual observation and mechanical properties of the film were determined as well as its spectral properties to assess the potential of halochromic film as gas sensor. The response of the PLA film to acidic and alkaline gas and its reversibility were tested. It was found that PEG increased the free volume of PLA and made it possible for the PEG and the dye to diffuse and entrap between PLA chains. However, increasing BCP did not have significant impact on the PLA film flexibility or reduced its halochromic sensitivity. The results revealed that the film showed significant effect on NH3 which the film change from yellow to purple within a second and could also change its color back to yellow in the absence of the VOC. This properties enables wide potential in various applications that requires high sensitivity, rapid response and continuous monitoring.
Class-B Power Amplifier with Si-Based Double-Gate MOSFET: A Circuit Perspective
Authors: Mbonane Sandile H. , Srivastava Viranjay
Published: January 2022

This research work designs a power amplifier with the use of Silicon-based Double-Gate (DG) MOSFET. It is a novel device used to amplify the input signal of an audio signal, etc. This research paper provides information on the problem identification in the existing models and its design objectives with its design constraints. It also reduces crossover distortion due to DG MOSFET instead of BJTs and MOSFETs in the class-B power amplifier. This is a low-power device for the mA range using SiO2 as a dielectric material.
Effects of Nanoscale Zero-Valent Iron on Soil-Leaching of Trinitrotoluene Contaminated Soil in Acid Rain Conditions
Authors: Kosanlavit Waraporn , Noinumsai Napat
Published: January 2022

The study of effects of nanoscale zero-valent iron (nZVI) on soil-leaching of trinitrotoluene (TNT) contaminated soil in the acid rain conditions is aim to the determination of the effect of nZVI which used as treatment material on soil leaching of TNT contaminated soil in raining condition. Research methodology, soil leaching batch reactor was designed for TNT remediation in soil with nZVI. The reactor was divided into three compartments for the different series of the experiment. Three compartments of the experiments were used for 1) TNT-contaminated soil column (without leaching), 2) TNT-contaminated soil was leached with rainwater, and 3) TNT-contaminated soil was mixed with nZVI and leached with rainwater. The leachants in the experiment were distilled water (pH 6-6.5) and artificial rainwater (pH≈5). The results of this study found the highest TNT removal efficiency was obtained from in the leaching column with nZVI, followed by the leaching column without nanoparticles and non-leaching column at 100.00, 37.25, and 10.65 % respectively. The leachant (artificial rain) which was slightly acidic in pH could remove some of TNT. The leachant improved solubility and transformation of nitro group in TNT to amino group by H ions addition. The results of the current study can be used to predict the circumstances of leaching TNT on-site in the rainy season.
Inhibitory Potential of Artificial Saliva Containing Vanillin against Biofilm Formation of Candida
Authors: Thaweboon Sroisiri , Thaweboon Boonyanit
Published: January 2022

Saliva plays a crucial role in oral health. Reduced salivary flow (hyposalivation) and xerostomia (dry mouth) are commonly found in many groups of patients, such as cancer patients with head and neck radiotherapy, patients taking medications with antisialogogic effects, diabetic patients, autoimmune patients, and the elderly. When salivary function is diminished, there is more risk of patients to develop opportunistic infections. One of therapeutic methods to restore lost or improve existing functions of natural saliva is the use of saliva substitutes. Several types of salivary substitutes have been developed to simulate human saliva as well as having antimicrobial property. Vanillin, an extensive flavor and aromatic component used worldwide, has been revealed to have antimicrobial potential against many types of bacteria yeasts and molds. The objective of this study was to evaluate the antimicrobial potential of vanillin-incorporated artificial saliva against biofilm formation of Candida. Artificial saliva containing different concentrations of vanillin (8, 4, 2, 1, 0.5 and 0.25 mg/mL) was prepared. Candida albicans ATCC 10231 and a clinical strain isolated from oral lesion of patient were used in this study. The Candida biofilm formation assay was performed on a 96-well plate by adding 150 μl 107colony forming unit (CFU)/ml of each Candida suspension and 50 μl of artificial saliva and incubated at 37°C in shaking incubator for 24 h. The vital Candida in biofilm formed on the bottom surface of microwell was determined by WST-8 microbial viability assay kit (Dojindo, USA). Artificial saliva without vanillin was used as a control. All tests were done in triplicate and repeated three times. Kruskal-Wallis and Dunn’ tests were used as statistical analysis. It was found that in the presence of vanillin (at concentrations > 0.5 mg/mL) the amount of vital biofilm formation of both strains of C. albicans was significantly reduced (31-56%) compared with a control. The suppressive activity was not different between both strains of Candida. Similarly, dose dependent effects were found except at 2 mg/mL and 1 mg/mL. The result was conformed to the previous study of our group that the incorporation of vanillin to surgical obturator resin could reduce the Candida biofilm formation to nearly 46-54%. The mechanisms of antifungal property of vanillin had been demonstrated to be the induction of oxidative stress, and an interference of metabolic pathways. In conclusion, artificial saliva containing vanillin exhibited a distinct inhibitory effect on biofilm formation of C. albicans as demonstrated in the present study. Attention is required for further studies to implement vanillin added artificial saliva to be used as a productive saliva substitute for the prevention or treatment of Candida infection.
IL-27 Signaling Promotes Th1 Responses and Is Required to Inhibit Fungal Growth in the Lung during Repeated Exposure to Aspergillus fumigatus
Authors: Strickland Ashley B , Sun Donglei , Sun Peng , Chen Yanli , Liu Gongguan , Shi Meiqing
Published: January 2022

Aspergillus fumigatus is an opportunistic fungal pathogen that causes a wide spectrum of diseases in humans, including life-threatening invasive infections as well as several hypersensitivity respiratory disorders. Disease prevention is predicated on the host’s ability to clear A. fumigatus from the lung while also limiting inflammation and preventing allergic responses. IL-27 is an important immunoregulatory cytokine, but its role during A. fumigatus infection remains poorly understood. In contrast to most infection settings demonstrating that IL-27 is anti-inflammatory, in this study we report that this cytokine plays a proinflammatory role in mice repeatedly infected with A. fumigatus. We found that mice exposed to A. fumigatus had significantly enhanced secretion of IL-27 in their lungs. Genetic ablation of IL-27Rα in mice resulted in significantly higher fungal burdens in the lung during infection. The increased fungal growth in IL-27Rα−/− mice was associated with reduced secretion of IL-12, TNF-α, and IFN-γ, diminished T-bet expression, as well as a reduction in CD4+ T cells and their activation in the lung, demonstrating that IL-27 signaling promotes Th1 immune responses during repeated exposure to A. fumigatus. In addition, infected IL-27Rα−/− mice displayed reduced accumulation of dendritic cells and exudate macrophages in their lungs, and these cells had a lower expression of MHC class II. Collectively, this study suggests that IL-27 drives type 1 immunity and is indispensable for inhibiting fungal growth in the lungs of mice repeatedly exposed to A. fumigatus, highlighting a protective role for this cytokine during fungal infection.
Pulmonary Embolism Initially Misdiagnosed as Perimyocarditis in a Young Patıent
Authors: Kilic Oguz , Akgun Alperen E. , Ufuk Furkan , Buber Ipek , Kilic Ismail D.
Published: January 2022

Pulmonary embolism is a common cardiovascular emergency. In case of delayed diagnosis and treatment morbidity and mortality is high. In this report, we presented a case of pulmonary embolism without apparent risk factors, which was initially misdiagnosed as peri/myocarditis.