bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on the Restoration of Class II Carious Cavities by Virtual Methods: Simulation of Mechanical Behavior
Authors: Țuculină Mihaela Jana , Staicu Adela Nicoleta , Munteanu Maria Cristina , Cumpătă Cristian Niky , Dimitriu Bogdan , Rîcă Ana Maria , Beznă Maria Cristina , Popa Dragoș Laurențiu , Popescu Alexandru Dan , Țîrcă Tiberiu
Published: July 2023

The restoration of class II cavities is predominantly carried out with composite materials. Due to the high failure rate in restoring this type of cavity, composite materials with much-improved properties and new application techniques have been promoted. The study aimed to analyze the mechanical behavior of several topical composite materials (nanocomposites, nanohybrids and ormocer) using different application techniques. In a lower second molar, a class II occlusal cavity was prepared. As filling materials, we used the following combinations: Admira Fusion and Admira Fusion Flow, Grandio and Grandio Flow, Filtek Supreme XT and Filtek Supreme Flow. These were applied using a snow plow, injection molded and Bichacho techniques. Three-dimensional scanning of the molar with the prepared cavity was performed, and then scanning of each layer of added composite material was performed, obtaining three-dimensional models. The virtual molar models were analyzed with software specific to the finite element analysis method, where their physical-mechanical properties were entered and assigned to the components of the virtual molar. Simulations at high forces specific to bruxism were then carried out and analyzed, and compared. The values of displacements and strain, for all six analyzed situations, are relatively small (range from 5.25 × 10−6–3.21 × 10−5 for displacement, 6.22 × 10−3–4.34 × 10−3 for strain), which validates all three methods and the materials used. As far as the stress values are concerned, they are similar for all methods (250–300 MPa), except for the snow plow and injection-molded techniques using Grandio and Grandio Flow composites, where the maximum von Mises stress value was more than double (approximately 700 MPa). When using the combination of Grandio and Grandio Flow materials, the 1 mm thickness of the fluid composite layer was found to have a major influence on occlusal forces damping as opposed to 0.5 mm. Therefore, the Bichacho technique is indicated at the expense of the snow plow and injection-molded techniques. The composite materials used by us in this study are state-of-the-art, with clear indications for restoring cavities resulting from the treatment of carious lesions. However, their association and application technique in the case of Class II cavities is of clinical importance for resistance to masticatory forces.
Aerodynamic Performance of Vertical-Axis Wind Turbines
Authors: Redchyts Dmytro , Portal-Porras Koldo , Tarasov Serhii , Moiseienko Svitlana , Tuchyna Uliana , Starun Natalya , Fernandez-Gamiz Unai
Published: July 2023

The nonstationary separated incompressible flows around Darrieus and Savonius rotors of vertical-axis wind turbines were investigated through computational simulation using the Reynolds averaged Navier–Stokes equations and Spalart–Allmaras turbulence model. The implicit finite-volume algorithm, the basis of which was artificial compressibility method, was chosen to obtain the numerical solution. The series of computational and physical experiments for Darrieus rotors with varied numbers and shapes of blades were performed. The detailed visualization of the flow was presented. The turbulent flows surrounding the Darrieus and Savonius rotors were studied, and as a part of these investigations, the major phases of vortex progress were identified. For this purpose, three series of computer tests on the aerodynamic and power properties of Savonius rotors with two and three buckets were performed, and their results are also presented. The influence of tip-speed ratio, solidity, and Reynolds numbers on the power coefficients of the Darrieus and Savonius rotors was investigated. It has been demonstrated that increasing Reynolds number from 104 to 106 causes a rise in Darrieus rotors power coefficient from 0.15 up to 0.5. The maximum values of power coefficient are moved away from higher values of tip-speed ratio from 2 to 5 as a result of a decrease in Darrieus rotor solidity from 1.0 to 0.33. The greatest power coefficient for a Savonius rotor with two blades is 0.23 and for a Savonius rotor with three blades is 0.19.
Marine Fisheries Management
Authors: Rumolo Paola
Published: July 2023

Effective marine fisheries management is a useful tool for counteracting the worldwide decline in fish stocks, which could have serious ecological and socioeconomic consequences [...]
Several Characteristics of Oidiodendron maius G.L. Barron Important for Heather Plants’ Controlled Mycorrhization
Authors: Mikheev Vyacheslav S. , Struchkova Irina V. , Churkina Ludmila M. , Brilkina Anna A. , Berezina Ekaterina V.
Published: July 2023

Oidiodendron maius G.L. Barron is a recognized fungal species capable of forming ericoid mycorrhiza with various positive effects on host plants; therefore, newly found and previously uncharacterized O. maius strains may be valuable for heather plants’ controlled mycorrhization. Characteristics of the O. maius F3860 strain were studied, i.e., mycelium growth on various nutrient media and the ability to secrete auxins and enzymes. O. maius F3860 grew rapidly on malt extract agar and potato dextrose agar. It was also able to grow on nutrient media suitable for heather plant cultivation. The presence of the flavonoids rutin and quercetin increased the mycelium growth rate compared to the control, starting from the 8th to the 13th days of cultivation. The ability to secrete auxins was confirmed with bioassay and thin-layer chromatography, and their content, as well as phytase activity, was estimated spectrophotometrically. Both in nutrient media with tryptophan and without it, O. maius F3860 secreted about 6 μg IAA/mL growth medium. O. maius F3860 possessed extracellular phytase, protease, and phenol oxidase activities. The investigation indicates O. maius F3860’s promise for heather seedling inoculation as an approach to increase their fitness.
Lung Epithelial Cell Line Immune Responses to Pneumocystis
Authors: Kottom Theodore J. , Carmona Eva M. , Limper Andrew H.
Published: July 2023

Pneumocystis sp. are fungal pathogens and members of the Ascomycota phylum. Immunocompetent individuals can readily eliminate the fungus, whereas immunocompromised individuals can develop Pneumocystis jirovecii pneumonia (PJP). Currently, over 500,000 cases occur worldwide, and the organism is listed on the recently released WHO fungal priority pathogens list. Overall, the number of PJP cases over the last few decades in developed countries with the use of highly effective antiretroviral therapy has decreased, but the cases of non-HIV individuals using immunosuppressive therapies have significantly increased. Even with relatively effective current anti-Pneumocystis therapies, the mortality rate remains 30–60% in non-HIV patients and 10–20% during initial episodes of PJP in HIV/AIDS patients. Although the role of alveolar macrophages is well studied and established, there is also well-established and emerging evidence regarding the role of epithelial cells in the immune response to fungi. This mini review provides a brief overview summarizing the innate immune response of the lung epithelium and various continuously cultured mammalian cell lines to Pneumocystis.
Critical Assessment of Phenotyping Cocktails for Clinical Use in an African Context
Authors: Leuschner Machel , Cromarty Allan Duncan
Published: July 2023

Interethnic and interindividual variability in in vivo cytochrome P450 (CYP450)-dependent metabolism and altered drug absorption via expressed transport channels such as P-glycoprotein (P-gp) contribute to the adverse drug reactions, drug–drug interaction and therapeutic failure seen in clinical practice. A cost-effective phenotyping approach could be advantageous in providing real-time information on in vivo phenotypes to assist clinicians with individualized drug therapy, especially in resource-constrained countries such as South Africa. A number of phenotyping cocktails have been developed and the aim of this study was to critically assess the feasibility of their use in a South African context. A literature search on library databases (including AccessMedicine, BMJ, ClinicalKey, MEDLINE (Ovid), PubMed, Scopus and TOXLINE) was limited to in vivo cocktails used in the human population to phenotype phase I metabolism and/or P-gp transport. The study found that the implementation of phenotyping in clinical practice is currently limited by multiple administration routes, the varying availability of probe drugs, therapeutic doses eliciting side effects, the interaction between probe drugs and extensive sampling procedures. Analytical challenges include complicated sample workup or extraction assays and impractical analytical procedures with low detection limits, analyte sensitivity and specificity. It was concluded that a single time point, non-invasive capillary sampling, combined with a low-dose probe drug cocktail, to simultaneously quantify in vivo drug and metabolite concentrations, would enhance the feasibility and cost-effectiveness of routine phenotyping in clinical practice; however, future research is needed to establish whether the quantitative bioanalysis of drugs in a capillary whole-blood matrix correlates with that of the standard plasma/serum matrixes used as a reference in the current clinical environment.
Fractionated Stereotactic Radiotherapy with Helical Tomotherapy for Brain Metastases: A Mono-Institutional Experience
Authors: Cuccia Francesco , D’Alessandro Salvatore , Carruba Giuseppe , Figlia Vanessa , Spera Antonio , Cespuglio Daniela , Mortellaro Gianluca , Iacoviello Giuseppina , Lo Casto Antonio , Tringali Giovanni , Craparo Giuseppe , Blasi Livio , Ferrera Giuseppe
Published: July 2023

Background: The present study reports on the outcomes of our mono-institutional experience of Helical Tomotherapy (HT)-based SRT for brain metastases. The use of this linac is less frequently reported for this kind of treatment. Methods: This retrospective study displays a series of patients treated with HT-SRT. The eligibility of using SRT for brain metastases was defined by a Karnofsky performance status of >70, a life expectancy of >6 months, and controlled extra-cranial disease; no SRT was allowed in the case of a number of brain metastases larger than 10. All the cases were discussed by a multidisciplinary board. Toxicity assessments were performed based on CTCAE v5.0. Survival endpoints were assessed using the Kaplan–Meier method, and univariate and multivariate analyses were carried out to identify any potential predictive factor for an improved outcome. Results: Sixty-four lesions in 37 patients were treated using HT-SRT with a median total dose of 30 Gy in five fractions. The median follow-up was 7 months, and the 1- and 2-year LC rates were both 92.5%. The IPFS rates were and 56.75% and 51.35%. The OS rates were 54% and 40%. The UA showed better IPFS rates significantly related to male sex (p = 0.049), a BED12 of ≥42 Gy (p = 0.006), and controlled extracranial disease (p = 0.03); in the MA, a favorable trend towards LC (p = 0.11) and higher BED (p = 0.11) schedules maintained a correlation with improved IPFS rates, although statistical significance was not reached. Conclusions: HT-based SRT for brain metastases showed safety and efficacy in our monoinstiutional experience. Higher RT doses showed statistical significance for improved outcomes of LC and OS.
Application of Pupillometry in Neurocritical Patients
Authors: Hsu Chiu-Hao , Kuo Lu-Ting
Published: July 2023

Pupillary light reflex (PLR) assessment is a crucial examination for evaluating brainstem function, particularly in patients with acute brain injury and neurosurgical conditions. The PLR is controlled by neural pathways modulated by both the sympathetic and parasympathetic nervous systems. Altered PLR is a strong predictor of adverse outcomes after traumatic and ischemic brain injuries. However, the assessment of PLR needs to take many factors into account since it can be modulated by various medications, alcohol consumption, and neurodegenerative diseases. The development of devices capable of measuring pupil size and assessing PLR quantitatively has revolutionized the non-invasive neurological examination. Automated pupillometry, which is more accurate and precise, is widely used in diverse clinical situations. This review presents our current understanding of the anatomical and physiological basis of the PLR and the application of automated pupillometry in managing neurocritical patients. We also discuss new technologies that are being developed, such as smartphone-based pupillometry devices, which are particularly beneficial in low-resource settings.
Triterpenes as Potential Drug Candidates for Rheumatoid Arthritis Treatment
Authors: Faustino Célia , Pinheiro Lídia , Duarte Noélia
Published: July 2023

Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease characterized by joint inflammation, swelling and pain. Although RA mainly affects the joints, the disease can also have systemic implications. The presence of autoantibodies, such as anti-cyclic citrullinated peptide antibodies and rheumatoid factors, is a hallmark of the disease. RA is a significant cause of disability worldwide associated with advancing age, genetic predisposition, infectious agents, obesity and smoking, among other risk factors. Currently, RA treatment depends on anti-inflammatory and disease-modifying anti-rheumatic drugs intended to reduce joint inflammation and chronic pain, preventing or slowing down joint damage and disease progression. However, these drugs are associated with severe side effects upon long-term use, including immunosuppression and development of opportunistic infections. Natural products, namely triterpenes with anti-inflammatory properties, have shown relevant anti-arthritic activity in several animal models of RA without undesirable side effects. Therefore, this review covers the recent studies (2017–2022) on triterpenes as safe and promising drug candidates for the treatment of RA. These bioactive compounds were able to produce a reduction in several RA activity indices and immunological markers. Celastrol, betulinic acid, nimbolide and some ginsenosides stand out as the most relevant drug candidates for RA treatment.
Influence of Research Factors and Al2O3 Layer Production Parameters on Tribological and Microstructural Properties
Authors: Korzekwa Joanna , Matczuk Robert , Hubkiewicz Kinga , Bara Marek , Niedźwiedź Mateusz , Bochenek Dariusz
Published: July 2023

The exclusion of systems supplying the lubricant from the outside makes it necessary to replace traditional sliding pairs with materials containing a lubricant component. Such solutions are carried out to prevent the formation of material tacks and, consequently, of adhesive wear, which must be avoided. The article presents the influence of research factors and parameters of Al2O3 layer production on tribological and microstructural properties. The input variables for the tests were the admixture of WS2 to the electrolyte, the type of sputtering of the samples for SEM tests, and the load on the oxide coating—TG15 material friction node. The surface morphology and cross-section of the oxide coatings as well as the tribological properties of the rubbing pair have been studied. Interactions between the input variables and the obtained test results have been analyzed using DOE—a 2k factorial design with one repetition. Pareto charts and two-way ANOVA were used to determine the relationship. The analysis of variance shows the influence of sample preparation on the calculation values of the size of nanopores and Al2O3 walls on the SEM image. Statistical analyzes also show that both the load and the type of electrolyte affected the values of the coefficient of friction and wear of the TG15 material; those values are the result of appropriate adhesion of the sliding film to the surface of the layer.
Shape Memory Alloys Applied to Automotive Adaptive Aerodynamics
Authors: Battaglia Miriam , Sellitto Andrea , Giamundo Angela , Visone Michele , Riccio Aniello
Published: July 2023

Shape memory alloys (SMAs) are gaining popularity in the fields of automotive and aerospace engineering due to their unique thermomechanical properties. This paper proposes a numerical implementation of a comprehensive constitutive model for simulating the thermomechanical behavior of shape memory alloys, with temperature and strain as control variables to adjust the shape memory effect and super elasticity effect of the material. By implementing this model as a user subroutine in the FE code Abaqus/Standard, it becomes possible to account for variations in material properties in complex components made of shape memory alloys. To demonstrate the potential of the proposed model, a skid plate system design is presented. The system uses bistable actuators with shape memory alloy springs to trigger plate movement. The kinematics and dynamics of the system are simulated, and effective loads are generated by the shape memory alloy state change due to the real temperature distribution in the material, which depends on the springs’ geometrical parameters. Finally, the performance of the actuator in switching between different configurations and maintaining stability in a specific configuration is assessed. The study highlights the promising potential of shape memory alloys in engineering applications and demonstrates the ability to use them in complex systems with accurate simulations.
Monte Carlo Simulation of TRIM Algorithm in Ceramic Biomaterial in Proton Therapy
Authors: Ekinci Fatih , Asuroglu Tunc , Acici Koray
Published: July 2023

Biomaterials play a crucial role in enhancing human health and quality of life. They are employed in applications such as tissue substitution, diagnostic tools, medical supplies, therapeutic treatments, regenerative medicine, and radiation dosimetric studies. However, their predisposition to proton therapy, which is a trending treatment in the world, has not been adequately studied. Ceramic biomaterials, known for their hardness and durability, offer versatile uses, especially in bone tissue replacements. The wide range of physical, mechanical, and chemical properties exhibited by ceramics has spurred extensive research, development, and application in this field. This study focuses on investigating and analyzing the ionization, recoils, phonon release, collision events, and lateral scattering properties of ceramic biomaterials that closely resemble bone tissue in proton therapy applications. Monte Carlo (MC) Transport of Ions in Matter (TRIM) simulation tools were utilized for this analysis. The results showed that Silicon dioxide exhibited the Bragg peak position closest to bone tissue, with a deviation of 10.6%. The average recoils differed by 1.7%, and the lateral scattering differed by 3.6%. The main innovation of this study lies in considering interactions such as recoil, collision events, phonon production, and lateral scattering when selecting biomaterials, despite their limited digitization and understanding. By evaluating all these interactions, the study aimed to identify the most suitable ceramic biomaterial to replace bone tissue in proton therapy.
Mechanical Properties and Wear Susceptibility Determined by Nanoindentation Technique of Ti13Nb13Zr Titanium Alloy after “Direct Laser Writing”
Authors: Jażdżewska Magdalena , Majkowska-Marzec Beata , Zieliński Andrzej , Ostrowski Roman , Frączek Aleksandra , Karwowska Gabriela , Olive Jean-Marc
Published: July 2023

Laser treatment has often been applied to rebuild the surface layer of titanium and its alloys destined for long-term implants. Such treatment has always been associated with forming melted and re-solidified thin surface layers. The process parameters of such laser treatment can be different, including the patterning of a surface by so-called direct writing. In this research, pulse laser treatment was performed on the Ti13Nb13Zr alloy surface, with the distance between adjacent laser paths ranging between 20 and 50 µm. The obtained periodic structures were tested to examine the effects of the scan distance on the microstructure using SEM, the roughness and chemical and phase composition using EDS and XRD, and the mechanical properties using the nanoindentation technique. After direct laser writing, the thickness of the melted layers was between 547 and 123 µm, and the surface roughness varied between 1.74 and 0.69 µm. An increase in hardness was observed after laser treatment. The highest hardness, 5.44 GPa, was obtained for the sample modified with a laser beam spacing of 50 µm. The value of the distance has been shown to be important for several properties and related to a complex microstructure of the thin surface layer close to and far from the laser path.
Synthesis of Zeolites from Coal Fly Ash Using Alkaline Fusion and Its Applications in Removing Heavy Metals
Authors: Koshlak Hanna
Published: July 2023

The article presents studies of the influence of parameters of synthesis modes and alkali concentration on the synthesis of zeolite materials from coal fly ash (CFA). The purpose of the study was to synthesise zeolite materials from CFA using the method of alkaline fusion and to determine the susceptibility of selected heavy-metal ions to removal from solutions in an ion exchange process on a selected mesoporous zeolite. It was found that the crystalline phase of sodalite was dominated in all of the samples synthesized. The specific surface area (SBET) of the samples was evaluated using the standard Brunauer–Emmett–Teller (BET) method using N2 sorption. Crystalline zeolite materials have been used to study the efficiency of removing heavy metals from aqueous solutions of Ni2+, Cd2+ and Pb2+. The adsorption data were analyzed using the Langmuir and Freundlich isotherm model. When comparing the estimated coefficient of determination (r2), it was noticed that the sorption data are more accurately described by the Langmuir isotherm and the pseudo-second-order kinetic model. The results of metal adsorption experiments suggest that the synthesized zeolite material has great potential to be used as an inexpensive and alternative source in the production of adsorbents.
Modeling of Hydrogen-Charged Notched Tensile Tests of an X70 Pipeline Steel with a Hydrogen-Informed Gurson Model
Authors: Depraetere Robin , De Waele Wim , Cauwels Margo , Depover Tom , Verbeken Kim , Hertelé Stijn
Published: July 2023

Hydrogen can degrade the mechanical properties of steel components, which is commonly referred to as “hydrogen embrittlement” (HE). Quantifying the effect of HE on the structural integrity of components and structures remains challenging. The authors investigated an X70 pipeline steel through uncharged and hydrogen-charged (notched) tensile tests. This paper presents a combination of experimental results and numerical simulations using a micro-mechanics-inspired damage model. Four specimen geometries and three hydrogen concentrations (including uncharged) were targeted, which allowed for the construction of a fracture locus that depended on the stress triaxiality and hydrogen concentration. The multi-physical finite element model includes hydrogen diffusion and damage on the basis of the complete Gurson model. Hydrogen-Assisted degradation was implemented through an acceleration of the void nucleation process, as supported by experimental observations. The damage parameters were determined through inverse analysis, and the numerical results were in good agreement with the experimental data. The presented model couples micro-mechanical with macro-mechanical results and makes it possible to evaluate the damage evolution during hydrogen-charged mechanical tests. In particular, the well-known ductility loss due to hydrogen was captured well in the form of embrittlement indices for the different geometries and hydrogen concentrations. The limitations of the damage model regarding the stress state are discussed in this paper.
An Overview of Angle Deviations of Fiber-Reinforced Polymer Composite Angular Laminates
Authors: Hwang Shun-Fa
Published: July 2023

After manufacturing, fiber-reinforced polymer composite laminates may have residual stresses, resulting in warpage in flat structures and angle changes in angular sections. These shape distortions may cause fitting mismatch problems under high-level assembly, and extra efforts to fix these problems may be needed. The present paper only makes an overview of the angle deviation of angular composite laminates made of either thermoset matrix with autoclave curing or thermoplastic matrix with thermoforming. Depending on the positive or negative angle deviation, spring-back or spring-in behavior is observed. There are many parameters, including intrinsic and extrinsic parameters, that could affect the angle deviation. In the first part of this review paper, experimental results concerning the effects of the part angle, part thickness, lay-up sequence, corner angle, flange size, tool material, tool surface, and cure cycle are summarized. Spring-in angles are generally obtained in this part. In the second part, several prediction methods, such as simple equations and finite element methods, are compared to indicate the considered parameters. Some have good agreement and some have larger errors. The crucial differences may be dependent on the micromechanical theories and the input properties of the composite and the constituents.
Investigating the Impact of Electrolyte Flow Velocity on the Resistivity of Vanadium Redox Batteries: A Theoretical Analysis and Experimental Data Comparison
Authors: Kislov Roman , Danin Zekharya , Averbukh Moshe
Published: July 2023

The influence of electrolyte velocity over the ion-exchange membrane surface on ion and vanadium redox batteries’ conductivity was formalized and quantified. The increase in electrolyte velocity dramatically improves proton conductivity, resulting in improved battery efficiency. An analysis of conductivity was carried out using a math model considering diffusion and drift ion motion together with their mass transport. The model is represented by the system of partial differential together with algebraic equations describing the steady-state mode of dynamic behavior. The theoretical solution obtained was compared qualitatively with the experimental results that prove the correctness of the submitted math model describing the influence of the electrolyte flow on the resistance of the vanadium redox battery. The presented theoretical approach was employed to conduct a parametric analysis of flow batteries, aiming to estimate the impact of electrolyte velocity on the output characteristics of these batteries.
Effects of Lectin Preparations from Microgramma vacciniifolia Rhizomes on the Survival, Digestive Enzymes, and Acetylcholinesterase Activity of Alphitobius diaperinus (Panzer) (Coleoptera: Tenebrionidae)
Authors: Santos Nataly Diniz de Lima , Albuquerque Lidiane Pereira de , de Amorim Marcus Mello Rego , de Oliveira Silva Juliane Nancy , Procópio Thamara Figueiredo , Santos Patryck Érmerson Monteiro dos , Paiva Patrícia Maria Guedes , Barros Mercia Rodrigues , Napoleão Thiago Henrique , Pontual Emmanuel Viana
Published: July 2023

In this study, we evaluated the susceptibility of Alphitobius diaperinus larvae and adults to saline extract (SE), lectin-rich fraction (FR), and isolated lectin (MvRL) from Microgramma vacciniifolia rhizomes. To determine immediate effects, larvae and adults were exposed to SE (10.5 mg/mL), FR (7.5 mg/mL), or MvRL (1.0 mg/mL) for 48 h. Live insects were evaluated for acetylcholinesterase (AChE) activity. The delayed effects of SE (10.5 mg/mL), FR (7.5 mg/mL), and MvRL (0.2 and 0.4 mg/mL) were checked by incubating the adults for 16 days with a diet containing the preparations. In vitro effects on gut digestive enzymes were investigated. All preparations showed immediate larvicidal effect but had no effect on adult survival. Extracts from FR-treated larvae showed higher AChE activity than control insects. In the delayed effect assay, the adults lost biomass after consuming SE and FR. FR was the most effective inhibitory agent of trypsin-like and amylase activities (88% and 65% inhibition, respectively). All preparations inhibited endoglucanase activity in 94–98%, while SE and FR inhibited exoglucanase activity in 93.2 and 94.1%, respectively. In conclusion, M. vacciniifolia rhizomes contain compounds (including MvRL) that affect the survival and physiology of A. diaperinus, acting as potential natural insecticides for controlling this pest.
Stabilization and Chaos Control of an Economic Model via a Time-Delayed Feedback Scheme
Authors: Hu Yang , Hu Guangping
Published: July 2023

This paper addresses the problem of chaos control in an economic mathematical dynamical model. By regarding the control variables as the bifurcation parameters, the stability of equilibria and the existence of Hopf bifurcations of the relevance feedback system are investigated, and the criterion of controllability for the chaotic system is obtained based on a time-delayed feedback control technique. Furthermore, numerical simulations are provided to demonstrate the feasibility of our methods and results.
Semi-Analytical Analysis of Drug Diffusion through a Thin Membrane Using the Differential Quadrature Method
Authors: Mustafa Abdelfattah , Salama Reda S. , Mohamed Mokhtar
Published: July 2023

The primary goal of this work is to solve the problem of drug diffusion through a thin membrane using a differential quadrature approach with drastically different shape functions, such as Lagrange interpolation and discrete singular convolution (the delta Lagrange kernel and the regularized Shannon kernel). A nonlinear partial differential equation with two time- and space-dependent variables governs the system. To reduce the two independent variables by one, the partial differential equation is transformed into an ordinary differential equation using a one-parameter group transformation. With the aid of the iterative technique, the differential quadrature methods change this equation into an algebraic equation. Then, using a MATLAB program, a code is created that solves this equation for each shape function. To ensure the validity, efficiency, and accuracy of the developed techniques, the computed results are compared to previous numerical and analytical solutions. In addition, the L∞ error is applied. As a consequence of the numerical outcomes, the differential quadrature method, which is primarily based on a discrete singular convolution shape function, is an effective numerical method that can be used to solve the problem of drug diffusion through a thin membrane, guaranteeing a higher accuracy, faster convergence, and greater reliability than other techniques.
Remimazolam Induction in a Patient with Super-Super Obesity and Obstructive Sleep Apnea: A Case Report
Authors: Lee Sou Hyun , Han Hyeji
Published: July 2023

Background: With the rising prevalence of obesity, anesthesiologists are expected to increasingly encounter patients with obesity, which poses challenges for anesthetic management. The use of remimazolam, an intravenous anesthetic agent approved in 2020, may be beneficial in these patients. However, its use in patients with super-super obesity remains underexplored. Case Description: A 55-year-old woman with a body mass index (BMI) of 60.6 kg/m2 and moderate obstructive sleep apnea (OSA) underwent laparoscopic sleeve gastrectomy under general anesthesia. The transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) technique was used along with the administration of remimazolam at a rate of 6 mg/kg/h based on the total body weight. The patient was sedated within 125 s without any signs of hemodynamic instability, and the surgery was completed successfully. Conclusions: This case study demonstrates the potential effectiveness of remimazolam infusion for inducing general anesthesia in patients with super-super obesity. The infusion rate, derived from the total body weight, yielded an outcome comparable with that observed in individuals without obesity. Further studies with larger cohorts are required to confirm these findings.
Organ-Sparing Surgery for Testicular Germ Cell Tumors: A Current Perspective
Authors: García Rojo Esther , Giannarini Gianluca , García Gómez Borja , Feltes Ochoa Javier Amalio , Guerrero Ramos Félix , Alonso Isa Manuel , Brime Menendez Ricardo , Saenz Calzada David Manuel , Justo Quintas Juan , Fraile Agustín , Manfredi Celeste , Romero Otero Javier
Published: July 2023

Background and Objectives: We aimed to evaluate the oncological and functional outcomes of organ-sparing surgery for testicular germ cell tumors, a procedure that seeks to strike a balance between effective cancer control and organ preservation, in the treatment of testicular tumors. We aimed to discuss the surgical technique and complications, and determine the appropriate candidate selection for this approach. Material and Methods: A comprehensive literature search was conducted to identify relevant studies on organ-sparing surgery for testicular tumors. Various databases, including PubMed, Embase, and Cochrane Library, were used. Studies reporting on surgical techniques, complications, and oncologic and functional outcomes were included for analysis. Results: Current evidence suggests that organ-sparing surgery for testicular germ cell tumors can be considered a safe and efficacious alternative to radical orchiectomy. The procedure is associated with adequate oncological control, as indicated by low recurrence rates and low complication rates. Endocrine testicular function can be preserved in around 80–90% of patients and paternity can be achieved in approximately half of the patients. Candidate selection for this surgery is typically based on the following criteria: pre-surgery normal levels of testosterone and luteinizing hormone, synchronous or metachronous bilateral tumors, tumor in a solitary testis, and tumor size less than 50% of the testis. Conclusions: Organ-sparing surgery for testicular germ cell tumors offers a promising approach that balances oncological control and preservation of testicular function. Further research, including large-scale prospective studies and long-term follow-ups, is warranted to validate the effectiveness and durability of organ-sparing surgery and to identify optimal patient selection criteria.
Assessment of Five Questionnaires for Chronic Obstructive Pulmonary Disease in a Southern Italian Population: A Proof-of-Concept Study
Authors: Dragonieri Silvano , Galloway Sean , Quaranta Vitaliano Nicola , Portacci Andrea , Vulpi Maria Rosaria , Santomasi Carla , Caringella Agnese , Carpagnano Giovanna Elisiana
Published: July 2023

Background and Objectives: Chronic obstructive pulmonary disease (COPD) is a growing burden to society, and remains underdiagnosed in Italy. This study aimed at evaluating five validated screening questionnaires to consider which one was the most accurate, and the optimal cut-off score for each to be considered for the Southern Italian population. Materials and Methods: A total of 144 patients were recruited in the study. The age range was 46–85 years. All subjects underwent spirometry, and completed the five questionnaires: CDQ, LFQ, COPD-PS, COPD-SQ, and CAPTURE. Receiver-operator curves (ROC) were drawn for each questionnaire. The area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), values for the optimal cut-off score and previously recommended score were calculated and compared. Results: Of the questionnaires, the CDQ, LFQ, and COPD-SQ had significant differences between COPD (n = 86) and non-COPD (n = 52) groups. The AUCs for each questionnaire with (95%CI) were: CAPTURE, 0.602 (0.431–0.773); CDQ, 0.714 (0.555–0.872); LFQ, 0.331 (0.183–0.479; COPD-PS, 0.652 (0.497–0.807); and COPD-SQ, 0.679 (0.520–0.837). Only the CDQ and COPD-SQ had significant AUC screening characteristics. The optimal cut-off values for the CDQ, LFQ, and COPD-PS were modified to 22, 10, and 4, respectively. The COPD-SQ remained at 17. Conclusion: The CDQ and COPD-SQ can discriminate between individuals with and without COPD in the Italian population. The CDQ has a moderate screening accuracy, and the COPD-PS and COPD-SQ have low accuracy, when the optimal cut-off scores are used. Of the five questionnaires assessed, the CDQ and COPD-SQ questionnaires could be used for screening for COPD in the Southern Italian population.
Fungal Infections Identified with Multiplex PCR in Severe COVID-19 Patients during Six Pandemic Waves
Authors: Bogdan Iulia , Reddyreddy Akash Reddy , Nelluri Aditya , Maganti Ram Kiran , Bratosin Felix , Fericean Roxana Manuela , Dumitru Catalin , Barata Paula Irina , Tapalaga Gianina , Marincu Iosif
Published: July 2023

Background and Objectives: With an increasing number of severe COVID-19 cases presenting with secondary fungal infections, this study aimed to determine the prevalence of fungal co-infections in severe COVID-19 patients across the six waves, identify the most common fungal pathogens associated with severe COVID-19, and explore any potential links between patient characteristics, therapeutic strategies, and the prevalence and type of fungal infection. Materials and Methods: A retrospective analysis was conducted on severe COVID-19 patients admitted to the Infectious Diseases and Pulmonology Hospital, “Victor Babes”, Romania, between March 2020 and August 2022. Samples were collected from respiratory specimens, blood, and urine, after which a standard nucleic acid extraction protocol was employed. Patients were divided into groups with and without fungal infections, identified using multiplex PCR. The groups were compared based on demographic data, comorbidities, pandemic wave number, and clinical outcomes. Results: Out of 288 patients, 96 (33.3%) had fungal infections, with Candida spp. being the most common. Patients with fungal infections had higher rates of obesity (35.4% vs. 21.4%, p = 0.010) and a higher Charlson comorbidity index (CCI > 2) (37.5% vs 25.0%, p = 0.027). Ventilator use was significantly higher in the fungal infection group (45.8% vs. 18.8%; p < 0.001), as was ICU admission (39.6% vs. 26.6%; p = 0.024) and mortality (32.3% vs 12.0%; p < 0.001). The distribution of different fungal species varied across the pandemic waves, with no statistical significance (p = 0.209). The mortality risk notably increased with the degree of drug resistance (OR for three or more drug resistances = 6.71, p < 0.001). The second, fourth, and fifth pandemic waves were significantly associated with higher mortality risk (OR = 3.72, 3.61, and 4.08, respectively, all p < 0.001). Aspergillus spp. and Mucor spp. infections were significantly associated with increased mortality risk (OR = 4.61 and 6.08, respectively, both p < 0.001). Conclusions: Our study indicates a significant presence of fungal co-infections among severe COVID-19 patients that is associated with increased morbidity and mortality, particularly in patients with drug-resistant infections. These findings underline the necessity for comprehensive diagnostic approaches and tailored treatment strategies in managing COVID-19 patients, especially during specific pandemic waves and in patients with particular fungal infections. Further research is required to understand the implications of these co-infections and their management.
Recovery of Dissolved Hydrogen Sulfide from Various Wastewater Streams Using Membranes and Other Relevant Techniques: A Review
Authors: Waheed Abdul , Aljundi Isam H. , Baig Umair
Published: July 2023

Given the significance of dissolved H2S, various techniques have been explored in the literature. The current review describes in detail the various membrane-based techniques, such as membrane contactors, for removing dissolved H2S from various wastewater streams. Various types of hydrophobic membranes have been used, with more emphasis placed on PVDF hollow fiber membranes. The hydrophobic membranes do not allow water to pass through, whereas H2S is readily allowed to pass through the membrane at ambient conditions. In addition, the use of monoethanol amine triazine (MEA-Triazine)- based H2S scavengers has also been described in detail, including the possible scavenging mechanism. The possibility of different types of byproducts has also been explained along with the possible routes to get rid of scavenger byproducts, such as apDTZ. The use of peroxy acetic acid has also been explained to oxidize and solubilize apDTZ. Furthermore, the use of vacuum-based dissolved H2S gas has also been described in detail. The application of the Knudsen and bulk diffusion models to the separation of dissolved H2S through the pores of the hollow fibers has also been explained. Finally, the future challenges and possible solutions along with concluding remarks have also been mentioned in the current review.
Numerical Simulation of Magnetic Field and Flow Field of Slab under Composite Magnetic Field
Authors: Su Zhijian , Wei Ren , Du Yida , Fan Wei , Chen Jin
Published: July 2023

A kind of composite magnetic field for flow control in slab mold is proposed, in which an electromagnetic stirring (EMS) is carried out near the meniscus and an electromagnetic braking (EMBr) is carried out near the outlet of the submerged entry nozzle (SEN), simultaneously. The yoke for the EMS and the EMBr is made independent from each other, with a ruler type for the EMBr. A three-dimensional model of the magnetic field calculation is established. The simulation results show that the magnetic induction intensity generated with the EMS mainly concentrates in the EMS area. The magnetic induction intensity generated with the EMBr has a large component in the EMS results, which has little effect on the flow of this area. Based on the composite magnetic field calculation results, the three-dimensional numerical simulation of the flow field is carried out, and the flow field obtained is compared to that without the magnetic field but with the EMS and the EMBr only, respectively. The results show that under the composite magnetic field, EMBr and EMS can play their respective roles well under certain conditions, the impact of the jet flow on the narrow face is reduced, and the stirring beneath the meniscus is intensified.
Gut Microbiota and Adipose Tissue Microenvironment Interactions in Obesity
Authors: Wang Congcong , Yi Zihan , Jiao Ye , Shen Zhong , Yang Fei , Zhu Shankuan
Published: July 2023

Obesity is an increasingly serious global health problem. Some studies have revealed that the gut microbiota and its metabolites make important contributions to the onset of obesity. The gut microbiota is a dynamic ecosystem composed of diverse microbial communities with key regulatory functions in host metabolism and energy balance. Disruption of the gut microbiota can result in obesity, a chronic metabolic condition characterized by the excessive accumulation of adipose tissue. Host tissues (e.g., adipose, intestinal epithelial, and muscle tissues) can modulate the gut microbiota via microenvironmental interactions that involve hormone and cytokine secretion, changes in nutrient availability, and modifications of the gut environment. The interactions between host tissues and the gut microbiota are complex and bidirectional, with important effects on host health and obesity. This review provides a comprehensive summary of gut microbiota changes associated with obesity, the functional roles of gut microbiota-derived metabolites, and the importance of the complex interactions between the gut microbiota and target tissues in the pathogenesis of obesity. It places particular emphasis on the roles of adipose tissue microenvironment interactions in the onset of obesity.
Exploring the Potential Performance of Fibroscan for Predicting and Evaluating Metabolic Syndrome using a Feature Selected Strategy of Machine Learning
Authors: Chiu Kuan-Lin , Chen Yu-Da , Wang Sen-Te , Chang Tzu-Hao , Wu Jenny L , Shih Chun-Ming , Yu Cheng-Sheng
Published: July 2023

Metabolic syndrome (MetS) includes several conditions that can increase an individual’s predisposition to high-risk cardiovascular events, morbidity, and mortality. Non-alcoholic fatty liver disease (NAFLD) is a predominant cause of cirrhosis, which is a global indicator of liver transplantation and is considered the hepatic manifestation of MetS. FibroScan® provides an accurate and non-invasive method for assessing liver steatosis and fibrosis in patients with NAFLD, via a controlled attenuation parameter (CAP) and liver stiffness measurement (LSM or E) scores and has been widely used in current clinical practice. Several machine learning (ML) models with a recursive feature elimination (RFE) algorithm were applied to evaluate the importance of the CAP score. Analysis by ANOVA revealed that five symptoms at different CAP and E score levels were significant. All eight ML models had accuracy scores > 0.9, while treebags and random forest had the best kappa values (0.6439 and 0.6533, respectively). The CAP score was the most important variable in the seven ML models. Machine learning models with RFE demonstrated that using the CAP score to identify patients with MetS may be feasible. Thus, a combination of CAP scores and other significant biomarkers could be used for early detection in predicting MetS.
A High-Functional-Density Integrated Inertial Switch for Super-Quick Initiation and Reliable Self-Destruction of a Small-Caliber Projectile Fuze
Authors: He Bo , Yuan Yong , Ren Jie , Lou Wenzhong , Feng Hengzhen , Zhang Mingrong , Lv Sining , Su Wenting
Published: July 2023

With the aim of achieving the combat technical requirements of super-quick (SQ) initiation and reliable self-destruction (SD) of a small-caliber projectile fuze, this paper describes a high-functional-density integrated (HFDI) inertial switch based on the “ON-OFF” state transition (i.e., almost no terminal ballistic motion). The reliable state switching of the HFDI inertial switch is studied via elastic–plastic mechanics and verified via both simulations and experiments. The theoretical and simulation results indicate that the designed switch can achieve the “OFF-ON” state transition in the internal ballistic system, and the switch can achieve the “ON-OFF” state transition in the simulated terminal ballistic system within 8 μs or complete the “ON-OFF” state transition as the rotary speed sharply decreases. The experimental results based on the anti-target method show the switch achieves the “ON-OFF” state transition on the μs scale, which is consistent with the simulation results. Compared with the switches currently used in small-caliber projectile fuzes, the HFDI inertial switch integrates more functions and reduces the height by about 44%.