bluuebunny/crossref_metadata_2025 huggingface dataset:
Modified Silica Nanoparticles from Rice Husk Supported on Polylactic Acid as Adsorptive Membranes for Dye Removal
Authors: Malafatti João Otávio Donizette , Tavares Francine Aline , Neves Tainara Ramos , Mascarenhas Bruno Cano , Quaranta Simone , Paris Elaine Cristina
Published: March 2023

Industrial effluents and wastewater treatment have been a mainstay of environmental preservation and remediation for the last decade. Silica nanoparticles (SiO2) obtained from rice husk (RH) are an alternative to producing low-cost adsorbent and agriculture waste recovery. One adsorption challenge is facilitating the adsorbate separation and reuse cycle from aqueous medium. Thus, the present work employs SiO2 supported on polylactic acid (PLA) nanofibers obtained by the electrospinning method for Rhodamine B (RhB) dye adsorption. The silica surface was modified with trimethylsilyl chloride (TMCS) to increase affinity towards organic compounds. As a result, the silanized surface of the silica from rice husk (RHSil) promoted an increase in dye adsorption attributed to the hydrophobic properties. The PLA fibers containing 40% SiO2 (w w−1) showed about 85–95% capacity adsorption. The pseudo-first-order kinetic model was demonstrated to be the best model for PLA:SiO2 RHSil nanocomposites, exhibiting a 1.2956 mg g−1 adsorption capacity and 0.01404 min−1 kinetic constant (k1) value. In the reuse assay, PLA:SiO2 membranes preserved their adsorption activity after three consecutive adsorption cycles, with a value superior to 60%. Therefore, PLA:SiO2 nanocomposites from agricultural waste are an alternative to “low-cost/low-end” treatments and can be used in traditional treatment systems to improve dye removal from contaminated waters.
Increasing the Thermal Stability and High-Temperature Strength of Vanadium Alloys by Strengthening with Nanosized Non-Metallic Particles
Authors: Ditenberg Ivan A. , Smirnov Ivan V. , Grinyaev Konstantin V. , Tyumentsev Alexander N. , Chernov Vyacheslav M. , Potapenko Mikhail M. , Kulinich Sergei A.
Published: March 2023

Using the methods of scanning and transmission electron microscopy, the features of the structural-phase state of a vanadium alloy of the V–Cr–Ta–Zr system after a combined treatment, which consisted in cyclic alternation of thermomechanical and chemical-heat treatments, were studied. The values of yield strength and ductility of the V–Cr–Ta–Zr alloy were determined, depending on the stabilization and test temperatures. It was established that, after the combined treatment, the structural-phase state of the V–Cr–Ta–Zr alloy was composite, in which the joint implementation of dispersion and substructural strengthening ensured the formation of a gradient grain structure with a polygonal state, the elements of which were fixed by nanosized ZrO2 particles characterized by a high thermal stability. Such modification of the microstructure was accompanied by an increase in the high-temperature strength and a shift in the upper limit of the temperature stability interval towards high temperatures, of up to 900 °C. It was assumed that the polygonal state inside the grains contributed to the implementation of cooperative mechanisms of the dislocation–disclination type, which ensured the accommodation of the material in the “high-strength state” under loading.
The Charge Distribution, Seebeck Coefficient, and Carrier Concentration of CuCr0.99Ln0.01S2 (Ln = Dy–Lu)
Authors: Korotaev Evgeniy V. , Syrokvashin Mikhail M. , Filatova Irina Yu. , Sotnikov Aleksandr V. , Kalinkin Alexandr V.
Published: March 2023

The atom oxidation states were determined using the binding energies of the core S2p-, Cu2p-, Cr2p-, and Ln3d-levels in CuCr0.99Ln0.01S2 (Ln = Dy–Lu) solid solutions. The charge distribution on the matrix elements (Cu, Cr, and S) remained unaffected after cationic substitution. The sulfur atoms were found to be in the S2− oxidation state, the copper–Cu+, and the chromium–Cr3+. The cationic substitution of the initial CuCrS2-matrix occurred via the isovalent mechanism. The obtained results were compared with the electrophysical properties for CuCr0.99Ln0.01S2. The measured carrier concentration was from 1017 to 1018 cm−3. The largest Seebeck coefficient value of 157 µV/K was measured for CuCr0.99Yb0.01S2 at 500 K. The cationic substitution with lanthanides allowed one to enhance the Seebeck coefficient of the initial CuCrS2-matrix.
Microstructure and Mechanical Properties of Y4Zr3O12-Added Fe–13.5Cr–2W Oxide-Dispersion-Strengthened Steels, Containing High Contents of C and N, Prepared by Mechanical Alloying and Two-Step Spark Plasma Sintering
Authors: Wu Yiheng , Huang Qunying , Zhang Ligang , Jiang Yong , Zhu Gaofan , Shen Jingjie
Published: March 2023

Oxide-dispersion-strengthened (ODS) steel is considered as a promising candidate structural material for nuclear applications. In this study, the microstructure and mechanical properties of Y4Zr3O12-added Fe–13.5Cr–2W ODS steels, containing high contents of C and N, prepared by mechanical alloying (MA) and two-step spark plasma sintering (SPS), were investigated. The results showed that pure Y4Zr3O12 powders, with a grain size of 3.5 nm, were well prepared with NH3·H2O addition by the sol-gel method in advance, in order to avoid the formation of some coarse or undesired oxides. W was completely dissolved into the matrix after 48 h of ball milling at 300 rpm, and the main elements were uniformly distributed on the surface of the milled powders. The unexpected face-centered cubic (FCC, γ)/body-centered cubic (BCC, α) dual-phase structure of the sintered specimens, could be explained by the unexpectedly high contents of C and N from the raw powder production process, fast-sintering characteristic of SPS, and inhibitory effect of W on the diffusion of C. The experimental results were approximately consistent with the simulation results from the Thermo Calc software. The temperature combination of 800 °C and 1100 °C during the SPS process, provided a relatively more homogeneous microstructure, while the combination of 750 °C and 1150 °C, provided the highest ultimate tensile strength (UTS), of 1038 MPa, with the highest uniform elongation (UE), of 6.2%. M23C6, Cr2O3, M2(C,N), and other precipitates, were mainly distributed at grain boundaries, especially at the triple junctions, which led to Cr depletion at grain boundaries.
Nano-Hybrid Ag@LCCs Systems with Potential Wound-Healing Properties
Authors: Corsaro Carmelo , Condorelli Marcello , Speciale Antonio , Cimino Francesco , Forte Giuseppe , Barreca Francesco , Spadaro Salvatore , Muscarà Claudia , D’Arrigo Manuela , Toscano Giovanni , D’Urso Luisa , Compagnini Giuseppe , Neri Fortunato , Saija Antonina , Fazio Enza
Published: March 2023

The synthesis of contaminant-free silver@linear carbon chains (Ag@LCCs) nanohybrid systems, at different Ag/LCCs ratios, by pulsed laser ablation was studied. The ablation products were first characterized by several diagnostic techniques: conventional UV–Vis optical absorption and micro-Raman spectroscopies, as well as scanning electron microscopy, operating in transmission mode. The experimental evidence was confirmed by the theoretical simulations’ data. Furthermore, to gain a deeper insight into the factors influencing metal@LCCs biological responses in relation to their physical properties, in this work, we investigated the bioproperties of the Ag@LCCs nanosystems towards a wound-healing activity. We found that Ag@LCC nanohybrids maintain good antibacterial properties and possess a better capability, in comparison with Ag NPs, of interacting with mammalian cells, allowing us to hypothesize that mainly the Ag@LCCs 3:1 might be suitable for topical application in wound healing, independent of (or in addition to) the antibacterial effect.
Formation of PLGA–PEDOT: PSS Conductive Scaffolds by Supercritical Foaming
Authors: Montes Antonio , Valor Diego , Penabad Yaiza , Domínguez Manuel , Pereyra Clara , de la Ossa Enrique Martínez
Published: March 2023

The usage of conjugated materials for the fabrication of foams intended to be used as therapeutic scaffolds is gaining relevance these days, as they hold certain properties that are not exhibited by other polymer types that have been regularly used until the present. Hence, this work aims to design a specific supercritical CO2 foaming process that would allow the production of porous polymeric devices with improved conductive properties, which would better simulate matrix extracellular conditions when used as therapeutic scaffolds (PLGA–PEDOT:PSS) systems. The effects of pressure, temperature, and contact time on the expansion factor, porosity, mechanical properties, and conductivity of the foam have been evaluated. The foams have been characterized by scanning electron and atomic force microscopies, liquid displacement, PBS degradation test, compression, and resistance to conductivity techniques. Values close to 40% porosity were obtained, with a uniform distribution of polymers on the surface and in the interior, expansion factors of up to 10 orders, and a wide range of conductivity values (2.2 × 10−7 to 1.0 × 10−5 S/cm) and mechanical properties (0.8 to 13.6 MPa Young’s modulus in compression test). The conductive and porous scaffolds that have been produced by supercritical CO2 in this study show an interesting potential for tissue engineering and for neural or cardiac tissue regeneration purposes due to the fact that electrical conductivity is a crucial factor for proper cell function and tissue development.
Effect of Free Cross-Linking Rate on the Molding of Bulk SiOC Ceramics
Authors: Zheng Lei , Sun Weilian , Ma Zhijian , Ji Hongchao , Sun Bo
Published: March 2023

Polymer-derived ceramics (PDCs) have many advantages in ceramic molding and ceramic properties, but because of the obvious volume shrinkage in the process of precursor transformation into ceramics, it is easy for defects to appear in the forming process of bulk PDCs. Herein, theoretical analyses and experimental studies were carried out to improve the quality of sintered samples and realize the parametric design of raw materials. Firstly, based on the HPSO/D4Vi cross-linking system, the mathematical model of the free cross-linking ratio was established, and the theoretical value was calculated. After that, the samples with different free cross-linking rates were heated at 450 °C and 650 °C for different holding times. It was found that the free cross-linking ratio (α) had a significant impact on the weight loss of the samples. When the difference of the α value was 10%, the difference of the samples’ weight loss ratio could reach 30%. Finally, the morphology of sintered products with different α values was analyzed, and it was found that obvious defects will occur when the free cross-linking ratio is too high or low; when this value is 40.8%, dense and crack-free bulk ceramics can be obtained. According to analysis of the chemical reaction and cross-linking network density during sintering, the appropriate value of the free cross-linking ratio and reasonable control of the cross-linking network are beneficial for reducing the loss of the main chain element and C element, alleviating the sintering stress, and thus obtaining qualified pressureless sintered bulk ceramic samples.
Long-Term Prestress Loss Calculation Considering the Interaction of Concrete Shrinkage, Concrete Creep, and Stress Relaxation
Authors: Han Weiwei , Tian Panpan , Lv Yigang , Zou Chaosheng , Liu Tao
Published: March 2023

In order to accurately calculate the long-term prestress losses of prestressed tendons, a time-varying model of long-term prestress loss considering the interaction between concrete shrinkage, creep, and the stress relaxation of prestressed tendons was constructed. Then, a method for calculating the long-term prestress losses of concrete structures was developed. A long-term prestress loss test of a prestressed concrete T-beam in a long-term field test environment was carried out. The measured values of long-term prestress losses are compared with the calculated results of JTG 3362-2018, AASHTO LRFD-2007, and the time-varying law model. The results show that the long-term effective tension of the T-beam decreases gradually with the increase in the load holding time. At the beginning of loading, the tensile force changes rapidly and then gradually slows down. The later the tensile age or the higher the initial loading stress level, the smaller the long-term prestress losses of the prestressed tendons. The long-term prestress loss values calculated by JTG 3362-2018, AASHTO LRFD-2007, and the time-varying law model increase with the increase in the load holding time. In the early stage of loading, the rate of change slows down and tends to be stable. The calculated results of JTG 3362-2018 and AASHTO LRFD-2007 are significantly different from the measured values. However, the calculated results of the time-varying law model are in good agreement with the measured values. The average coefficients of variation of the long-term prestress loss calculated by JTG 3362-2018, AASHTO LRFD-2007, and the time-varying law model are 17%, 10%, and 5%, respectively. The time-varying law model of the long-term prestress losses of prestressed tendons is accurate, and the long-term prestress loss of prestressed reinforcement can be predicted effectively.
Design of Ti-Mo-W Alloys and Its Correlation with Corrosion Resistance in Simulated Body Fluid (SBF)
Authors: Ghica Ştefan-Ioan , Ghica Valeriu-Gabriel , Petrescu Mircea-Ionuţ , Iacob Gheorghe , Geantă Victor , Buzatu Mihai , Ungureanu Elena
Published: March 2023

Titanium and its based alloys are frequently selected for designing biomedical implants and it is thus necessary to study as detailed as possible their corrosion behavior in biological solutions, such as those in the human body environment. In this paper, with the use of molecular orbital calculation, we designed and developed alloys in the Ti-19Mo-xW system (x = 7, 8, 9, and 10 wt%) and investigated the influence of different contents of tungsten on the behavior of Ti-19Mo-xW alloy samples following corrosion in simulated body fluid (SBF). The values of Bo¯ (bond order) and Md¯ (the metal—orbital energy level) were calculated for each alloy and correlations were established between Bo¯ and the content of tungsten. It was found that with the increase in tungsten content, the value of Bo¯ increases. Regarding the values of the corrosion resistance in SBF that resulted from the investigated alloys, the Ti19Mo7W alloy is distinguished by the lowest value of the corrosion current density and the lowest corrosion rate.
Unimolecular Micelles from Randomly Grafted Arborescent Copolymers with Different Core Branching Densities: Encapsulation of Doxorubicin and In Vitro Release Study
Authors: Alsehli Mosa , Gauthier Mario
Published: March 2023

A series of amphiphilic arborescent copolymers of generations G1 and G2 with an arborescent poly(γ-benzyl L-glutamate) (PBG) core and poly(ethylene oxide) (PEO) chain segments in the shell, PBG-g-PEO, were synthesized and evaluated as drug delivery nanocarriers. The PBG building blocks were generated by ring-opening polymerization of γ-benzyl L-glutamic acid N-carboxyanhydride (Glu-NCA) initiated with n-hexylamine. Partial or full deprotection of the benzyl ester groups followed by coupling with PBG chains yielded a comb-branched (arborescent polymer generation zero or G0) PBG structure. Additional cycles of deprotection and grafting provided G1 and G2 arborescent polypeptides. Side chains of poly(ethylene oxide) were then randomly grafted onto the arborescent PBG substrates to produce amphiphilic arborescent copolymers. Control over the branching density of G0PBG was investigated by varying the length and the deprotection level of the linear PBG substrates used in their synthesis. Three G0PBG cores with different branching densities, varying from a compact and dense to a loose and more porous structure, were thus synthesized. These amphiphilic copolymers behaved similar to unimolecular micelles in aqueous solutions, with a unimodal number- and volume-weighted size distributions in dynamic light scattering measurements. It was demonstrated that these biocompatible copolymers can encapsulate hydrophobic drugs such as doxorubicin (DOX) within their hydrophobic core with drug loading efficiencies of 42–65%. Sustained and pH-responsive DOX release was observed from the unimolecular micelles, which suggests that they could be useful as drug nanocarriers for cancer therapy.
Sandwich Plate Structure Periodically Attached by S-Shaped Oscillators for Low Frequency Ship Vibration Isolation
Authors: Shen Chaoming , Huang Jie , Zhang Zexin , Xue Jingya , Qian Denghui
Published: March 2023

Locally resonant phononic crystals are a kind of artificial periodic composite material/structure with an elastic wave band gap that show attractive application potential in low-frequency vibration control. For low-frequency vibration control problems of ship power systems, this paper proposes a phononic crystal board structure, and based on the Bloch theorem of periodic structure, it uses a finite element method to calculate the band structure and the displacement fields corresponding to the characteristic mode and vibration transmission curve of the corresponding finite periodic sandwich plate structure, and the band gap characteristics are studied. The mechanism of band gap formation is mainly attributed to the mode coupling of the phononic crystal plate structure. Numerical results show that the sandwich plate structure has a double periodicity, so it has a multi-stage elastic wave band gap, which can fully inhibit the transmission of flexural waves and isolate the low-frequency flexural vibration. The experimental measurements of flexural vibration transmission spectra were conducted to validate the accuracy and reliability of the numerical calculation method. On this basis, the potential application of the proposed vibration isolation method in a marine power system is discussed. A vibration isolation platform mounted on a steel plate is studied by numerical simulation, which can isolate low-frequency vibration to protect electronic equipment and precision instruments.
Studies on PVP-Based Hydrogel Polymers as Dressing Materials with Prolonged Anticancer Drug Delivery Function
Authors: Sobczak-Kupiec Agnieszka , Kudłacik-Kramarczyk Sonia , Drabczyk Anna , Cylka Karolina , Tyliszczak Bozena
Published: March 2023

Tamoxifen is a well-known active substance with anticancer activity. Currently, many investigations are performed on the development of carriers that provide its effective delivery. Particular attention is directed toward the formation of cyclodextrin–drug complexes to provide prolonged drug delivery. According to our knowledge, carriers in the form of polyvinylpyrrolidone (PVP)/gelatin-based hydrogels incorporated with β-cyclodextrin–tamoxifen complexes and additionally modified with nanogold have not been presented in the literature. In this work, two series of these materials have been synthesized—with tamoxifen and with its complex with β-cyclodextrin. The process of obtaining drug carrier systems consisted of several stages. Firstly, the nanogold suspension was obtained. Next, the hydrogels were prepared via photopolymerization. The size, dispersity and optical properties of nanogold as well as the swelling properties of hydrogels, their behavior in simulated physiological liquids and the impact of these liquids on their chemical structure were verified. The release profiles of tamoxifen from composites were also determined. The developed materials showed swelling capacity, stability in tested environments that did not affect their structure, and the ability to release drugs, while the release process was much more effective in acidic conditions than in alkaline ones. This is a benefit considering their use for anticancer drug delivery, due to the fact that near cancer cells, there is an acidic environment. In the case of the composites containing the drug–β-cyclodextrin complex, a prolonged release process was achieved compared to the drug release from materials with unbound tamoxifen. In terms of the properties and the composition, the developed materials show a great application potential as drug carriers, in particular as carriers of anticancer drugs such as tamoxifen.
Evolution of the Strengthening Effects of In Situ TiB Fibers in a Ti Composite with Various Levels of Thermal Processing
Authors: Zhao Peifeng , Ma Fengcang , Liu Ping , Li Wei , Liu Xinkuan , Chen Xiaohong , Zhang Ke
Published: March 2023

Thermal processing is a useful method for improving the strengthening effects of fibers used to reinforce metal matrix composites (MMCs), but the corresponding models have not been constructed. In this work, a Ti matrix composite (TMC) reinforced by in situ TiB fibers was prepared, then thermal processing was applied to it at different levels of deformation to align the TiB fibers along the loading direction. Changes in the microstructure of the matrix, the orientation and the aspect ratio of the TiB fibers during this process were investigated. It was found that the aspect ratio of TiB fibers decreased sharply after a large amount of deformation. The strengthening effect of TiB fibers in the composite was simulated by strengthening models of the fibers, and the simulated results were verified by the results of tensile tests. The modeled results show that the strengthening factor (C0) of the in situ TiB fibers improved from 0.125 in the as-cast composite to 0.520, 0.688 and 0.858 by the processes with deformation ratios of 0.39, 0.26 and 0.14, respectively. The results of the tensile tests showed that the measured values of C0 gradually deviated from the modeled ones with an increase in the ratio of deformation applied during processing, and the deviation could be interpreted with the strengthening models.
Interior Bubbling Solutions for an Elliptic Equation with Slightly Subcritical Nonlinearity
Authors: El Mehdi Khalil , Mohamed Salem Fatimetou
Published: March 2023

In this paper, we considered the Neumann elliptic equation (Pε): −Δu+K(x)u=u(n+2)/(n−2)−ε, u>0 in Ω, ∂u/∂ν=0 on ∂Ω, where Ω is a smooth bounded domain in Rn, n≥6, ε is a small positive real and K is a smooth positive function on Ω¯. Using refined asymptotic estimates of the gradient of the associated Euler–Lagrange functional, we constructed simple and non-simple interior bubbling solutions of (Pε) which allowed us to prove multiplicity results for (Pε) provided that ε is small. The existence of non-simple interior bubbling solutions is a new phenomenon for the positive solutions of subcritical problems.
A Clinical Prediction Model of Overall Survival for Patients with Cervical Cancer Aged 25–69 Years
Authors: Fan Wenli , Lu Qin , Liu Guokun
Published: March 2023

Aims: This study aims to develop a prediction tool for the overall survival of cervical cancer patients. Methods: We obtained 4116 female patients diagnosed with cervical cancer aged 25–69 during 2008–2019 from the Surveillance, Epidemiology, and End Results Program. The overall survival between groups was illustrated by the Kaplan–Meier method and compared by a log-rank test adjusted by the Bonferroni–Holm method. We first performed the multivariate Cox regression analysis to evaluate the predictive values of the variables. A prediction model was created using cox regression based on the training set, and the model was presented as a nomogram. The proposed nomogram was designed to predict the 1-year, 3-year, and 5-year overall survival of patients with cervical cancer. Besides the c-index, time-dependent receiver operating curves, and calibration curves were created to evaluate the accuracy of the nomogram at the timepoint of one year, three years, and five years. Results: With a median follow-up of 54 (28, 92) months, 1045 (25.39%) patients were deceased. Compared with alive individuals, the deceased were significantly older and the primary site was more likely to be the cervix uteri site, large tumor size, higher grade, and higher combined summary stage (all p values < 0.001). In the multivariate Cox regression, age at diagnosis, race, tumor size, grade, combined summary stage, pathology, and surgery treatment were significantly associated with the all-cause mortality for patients with cervical cancer. The proposed nomogram showed good performance with a C-index of 0.82 in the training set. The 1-year, 3-year, and 5-year areas under the curves (with 95% confidence interval) of the receiver operating curves were 0.88 (0.84, 0.91), 0.84 (0.81, 0.87), and 0.83 (0.80, 0.86), respectively. Conclusions: This study develops a prediction nomogram model for the overall survival of cervical cancer patients with a good performance. Further studies are required to validate the prediction model further.
PDMS Micropatterns Coated with PDA and RGD Induce a Regulatory Macrophage-like Phenotype
Authors: Pham Hoang Lan , Yang Da Hyun , Chae Woo Ri , Jung Jong Hyeok , Hoang Thi Xoan , Lee Nae Yoon , Kim Jae Young
Published: March 2023

Regulatory macrophages (Mreg) are a special cell type that present a potential therapeutic strategy for various inflammatory diseases. In vitro, Mreg generation mainly takes 7–10 days of treatment with chemicals, including cytokines. In the present study, we established a new approach for Mreg generation using a three-dimensional (3D) micropatterned polydimethylsiloxane (PDMS) surface coated with a natural biopolymer adhesive polydopamine (PDA) and the common cell adhesion peptide motif arginylglycylaspartic acid (RGD). The 3D PDMS surfaces were fabricated by photolithography and soft lithography techniques and were subsequently coated with an RGD+PDA mixture to form a surface that facilitates cell adhesion. Human monocytes (THP-1 cells) were cultured on different types of 2D or 3D micropatterns for four days, and the cell morphology, elongation, and Mreg marker expression were assessed using microscopic and flow cytometric analyses. The cells grown on the PDA+RGD-coated 3D micropatterns (20-µm width/20-µm space) exhibited the most elongated morphology and strongest expression levels of Mreg markers, such as CD163, CD206, CD209, CD274, MER-TK, TREM2, and DHRS9. The present study demonstrated that PDA+RGD-coated 3D PDMS micropatterns successfully induced Mreg-like cells from THP-1 cells within four days without the use of cytokines, suggesting a time- and cost-effective method to generate Mreg-like cells in vitro.
Development and Performance Evaluation of Photovoltaic (PV) Evaluation and Fault Detection System Using Hardware-in-the-Loop Simulation for PV Applications
Authors: Le Phuong-Truong , Tsai Huan-Liang , Le Phuong-Long
Published: March 2023

This paper originally presents a photovoltaic (PV) evaluation and fault detection (PVEFD) system for PV applications based on the Internet of Things (IoT) technology. The PVEFD system consists of an STM32F103C8T6 chip with a 32-bit Arm Cortex-M3 reduced instruction set computer (RISC) and 12-bit resolution analog-to-digital converter (ADC) to measure important parameters of PV applications, such as solar irradiance as well as the back-surface cell temperature, operating voltage, and output current of PV devices. The measured data of irradiance as well as back-surface cell temperature and operating voltage of PV devices are then fed into a built-in PV model in the on-chip Arm Cortex-M3 RISC for hardware-in-the-loop (HIL) simulation to obtain the simulated output current and power of PV devices. The resulting data are transmitted to a cloud server for remote monitoring and automatic warning function through a Raspberry PI 3 module and WiFi network. The simulation results are compared with in-field measurement data from PV modules and displayed on a human–machine interface (HMI) and an Android app. The results of the study illustrated that the proposed system features high accuracy and sufficient confidence. Furthermore, the fault detection function through the built-in HIL simulation function in PV systems was validated. Therefore, the proposed system is a small, compact, and cost-effective HIL-on-chip machine for remote surveillance of PV power systems.
Green Synthesis of NiO Nanoflakes Using Bitter Gourd Peel, and Their Electrochemical Urea Sensing Application
Authors: Naz Irum , Tahira Aneela , Shah Aqeel Ahmed , Bhatti Muhammad Ali , Mahar Ihsan Ali , Markhand Mehnaz Parveen , Mastoi Ghulam Murtaza , Nafady Ayman , Medany Shymaa S. , Dawi Elmuez A. , Saleem Lama M. , Vigolo Brigitte , Ibupoto Zafar Hussain
Published: March 2023

To determine urea accurately in clinical samples, food samples, dairy products, and agricultural samples, a new analytical method is required, and non-enzymatic methods are preferred due to their low cost and ease of use. In this study, bitter gourd peel biomass waste is utilized to modify and structurally transform nickel oxide (NiO) nanostructures during the low-temperature aqueous chemical growth method. As a result of the high concentration of phytochemicals, the surface was highly sensitive to urea oxidation under alkaline conditions of 0.1 M NaOH. We investigated the structure and shape of NiO nanostructures using powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). In spite of their flake-like morphology and excellent crystal quality, NiO nanostructures exhibited cubic phases. An investigation of the effects of bitter gourd juice demonstrated that a large volume of juice produced thin flakes measuring 100 to 200 nanometers in diameter. We are able to detect urea concentrations between 1–9 mM with a detection limit of 0.02 mM using our urea sensor. Additionally, the stability, reproducibility, repeatability, and selectivity of the sensor were examined. A variety of real samples, including milk, blood, urine, wheat flour, and curd, were used to test the non-enzymatic urea sensors. These real samples demonstrated the potential of the electrode device for measuring urea in a routine manner. It is noteworthy that bitter gourd contains phytochemicals that are capable of altering surfaces and activating catalytic reactions. In this way, new materials can be developed for a wide range of applications, including biomedicine, energy production, and environmental protection.
Improved Dielectrically Modulated Quad Gate Schottky Barrier MOSFET Biosensor
Authors: Esakki Papanasam , Kumar Prashanth , Esakki Manikandan , Venkatesh Adithya
Published: March 2023

A novel Schottky barrier MOSFET with quad gate and with source engineering has been proposed in this work. A high-κ dielectric is used at the source side of the channel, while SiO2 is used at the drain side of the channel. To improve the carrier mobility, a SiGe pocket region is created at the source side of the channel. Physical and electrical characteristics of the proposed device are compared with conventional double gate Schottky barrier MOSFET. It has been observed that the proposed device exhibits better performance, with a higher ION/IOFF ratio and lower subthreshold slope. The high-κ dielectric, along with the SiGe pocket region, improves tunneling probability, while aluminum, along with SiO2 at the drain side, broadens the drain/channel Schottky barrier and reduces the hole tunneling probability, resulting in a reduced OFF-state current. Further, the proposed device is used as a biosensor to detect both the charged and neutral biomolecules. Biosensors are made by creating a nanocavity in the dielectric region near the source end of the channel to capture biomolecules. Biomolecules such as streptavidin, biotin, APTES, cellulose and DNA have unique dielectric constants, which modulates the electrical parameters of the device. Different electrical parameters, viz., the electric field, surface potential and drain current, are analyzed for each biomolecule. It has been observed that drain current increases with the dielectric constant of the biomolecules. Furthermore, the sensitivity and selectivity of the proposed biosensors is better than that of conventional biosensors made using double gate Schottky barrier MOSFETs. Sensitivity is almost twice that of a conventional sensor, while selectivity is six to twelve times higher than a conventional one.
Mechanical Properties of 3-Hydroxybutyric Acid-Induced Vesicles
Authors: Jung Seung Jun , Hadinoto Kunn , Park Jin-Won
Published: March 2023

The vesicle mechanical behaviors were studied upon its exposure to 3-hydroxybutyric acid using an atomic force microscope (AFM). Dipalmitoylphosphatidylcholine (DPPC) and 3-hydroxybutyric acid were used to manufacture the vesicles at their desired ratio. The deflection of an AFM probe with respect to its displacement was measured after characterizing the vesicle adsorption. The movement was analyzed with the Hertzian model to understand the physical behavior of the vesicles. However, in the deflection just prior to the first penetration, the model was a good fit, and the vesicle mechanical moduli were calculated. The moduli became lower with the higher ratio of 3-hydroxybutyric acid to DPPC, but the moduli were saturated at 0.5 of the ratio. These results appear to be the basis for the function of the metabolism associated with 3-hydroxybutyric acid, i.e., anesthetization and glycemic control, on the physical properties of cell membranes.
5-HT2C Receptor Stimulation in Obesity Treatment: Orthosteric Agonists vs. Allosteric Modulators
Authors: Przegaliński Edmund , Witek Kacper , Wydra Karolina , Kotlińska Jolanta H. , Filip Małgorzata
Published: March 2023

Obesity is a substantial health and economic issue, and serotonin (5-hydroxytryptamine, 5-HT) is an important neurotransmitter system involved in the regulation of body weight. The 5-HT2C receptors (5-HT2CRs), one of 16 of the 5-HT receptor (5-HTRs) subtypes, play a significant role in food intake and body weight control. In this review, we focused on the 5-HTR agonists, such as fenfluramines, sibutramine, and lorcaserin, which act directly or indirectly at 5-HT2CRs and have been introduced into the clinic as antiobesity medications. Due to their unwanted effects, they were withdrawn from the market. The 5-HT2CR positive allosteric modulators (PAMs) can be potentially safer active drugs than 5-HT2CR agonists. However, more in vivo validation of PAMs is required to fully determine if these drugs will be effective in obesity prevention and antiobesity pharmacology treatment. Methodology strategy: This review focuses on the role of 5-HT2CR agonism in obesity treatment, such as food intake regulation and weight gain. The literature was reviewed according to the review topic. We searched the PubMed and Scopus databases and Multidisciplinary Digital Publishing Institute open-access scientific journals using the following keyword search strategy depending on the chapter phrases: (1) “5-HT2C receptor” AND “food intake”, and (2) “5-HT2C receptor” AND “obesity” AND “respective agonists”, and (3) “5-HT2C receptor” AND “PAM”. We included preclinical studies (only present the weight loss effects) and double-blind, placebo-controlled, randomized clinical trials published since the 1975s (mostly related to antiobesity treatment), and excluded the pay-walled articles. After the search process, the authors selected, carefully screened, and reviewed appropriate papers. In total, 136 articles were included in this review.
Phloretamide Prevent Hepatic and Pancreatic Damage in Diabetic Male Rats by Modulating Nrf2 and NF-κB
Authors: Al-Hussan Rasha , Albadr Nawal A. , Alshammari Ghedeir M. , Almasri Soheir A. , Yahya Mohammed Abdo
Published: March 2023

This study examined the effect of phloretamide, a metabolite of phloretin, on liver damage and steatosis in streptozotocin-induced diabetes mellitus (DM) in rats. Adult male rats were divided into two groups: control (nondiabetic) and STZ-treated rats, each of which was further treated orally with the vehicle phloretamide 100 mg or 200 mg. Treatments were conducted for 12 weeks. Phloretamide, at both doses, significantly attenuated STZ-mediated pancreatic β-cell damage, reduced fasting glucose, and stimulated fasting insulin levels in STZ-treated rats. It also increased the levels of hexokinase, which coincided with a significant reduction in glucose-6 phosphatase (G-6-Pase), and fructose-1,6-bisphosphatase 1 (PBP1) in the livers of these diabetic rats. Concomitantly, both doses of phloretamide reduced hepatic and serum levels of triglycerides (TGs) and cholesterol (CHOL), serum levels of low-density lipoprotein cholesterol (LDL-c), and hepatic ballooning. Furthermore, they reduced levels of lipid peroxidation, tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), mRNA, and total and nuclear levels of NF-κB p65, but increased mRNA levels, total and nuclear levels of Nrf2, as well as levels of reduced glutathione (GSH), superoxide dismutase (SOD-1), catalase (CAT), and heme-oxygenase-1 (HO-1) in the livers of diabetic rats. All of these effects were dose-dependent. In conclusion, phloretamide is a novel drug that could ameliorate DM-associated hepatic steatosis via its powerful antioxidant and anti-inflammatory effects. Mechanisms of protection involve improving the β-cell structure and hepatic insulin action, suppressing hepatic NF-κB, and stimulating hepatic Nrf2.
Association of Bioelectrical Impedance Phase Angle with Physical Performance and Nutrient Intake of Older Adults
Authors: Unterberger Sandra , Aschauer Rudolf , Zöhrer Patrick A. , Draxler Agnes , Aschauer Mirjam , Kager Benno , Franzke Bernhard , Strasser Eva-Maria , Wagner Karl-Heinz , Wessner Barbara
Published: March 2023

In recent years, the phase angle (PhA) as a raw bioelectrical impedance analysis variable has gained attention to assess cell integrity and its association to physical performance in either sports-related or clinical settings. However, data on healthy older adults are scarce. Therefore, data on body composition, physical performance and macronutrient intake from older adults (n = 326, 59.2% women, 75.2 ± 7.2 years) were retrospectively analyzed. Physical performance was evaluated by the Senior Fitness Test battery, gait speed, timed up and go and handgrip strength. Body composition was determined by the BIA and dual-energy X-ray absorptiometry (from a subgroup of n = 51). The PhA was negatively associated with the timed up and go test and age (r = −0.312 and −0.537, p < 0.001), and positively associated with the 6 min walk test, 30 s chair stand, handgrip strength, gait speed and physical performance score (r = 0.170–0.554, p < 0.05), but not protein intake (r = 0.050, p = 0.386). Hierarchical multiple regression analysis showed that especially age, sex, BMI, but also the PhA predicted the performance test outcomes. In conclusion, the PhA seems to be an interesting contributor to physical performance, but sex- and age-specific norm values still need to be determined.
The Toxicological Analysis and Toxicological Risk Assessment of Chosen Elemental Impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) in Green Tea (Camellia sinensis (L.)) Infusions
Authors: Frydrych Adrian , Noga Maciej , Milan Justyna , Kondratowicz-Pietruszka Elżbieta , Krośniak Mirosław , Jurowski Kamil
Published: March 2023

Our study’s objective is to evaluate the potential health effects of elemental impurities (Ag, Au, Co, Cr, Cs, Li, Mo, Se, and Sr) found in green tea infusions (Camellia sinensis (L.)). The ICP-MS-based methodology was employed for elemental analysis and a detailed health risk evaluation based on weekly consumption (μg/L of infusion/week). The provisional tolerable weekly intake (PTWI), established by the Joint FAO Expert Committee on infusion/week/month based on existing literature data, was then compared to the subjects with data from the available literature. The exposure of the study items to Co ranged from 0.07904 to 0.85421 μg/day. On the contrary, the ICH (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) guidelines state that the established permitted daily exposure PDE (oral exposure) for Co is 50 μg/day. The PDE of lithium is around 560 μg/day, and according to our study, the estimated daily exposure of the evaluated products to Li fell between 0.0185 and 0.7170 μg/day. Our research also revealed modest concentrations of Cs (0.399–2.654 μg/L), Mo (0.0113–0.107 μg/L), and Sr (9.848–22.331 μg/L) in infusions. The recognized PDE for molybdenum is approximately 3400 μg/day. Only two samples contained silver, and when considering daily consumption, the predicted daily exposure to Ag is between 4.4994 and 0.03122 μg/day. The amounts of all evaluated elements in a daily dose of green tea infusions should not harm the consumer’s health. Further considerations should take aspects, such as constant change and environmental pollution, into account.
Insulin, Testosterone, and Albumin in Term and Preterm Breast Milk, Donor Milk, and Infant Formula
Authors: Vass Réka A. , Bell Edward F. , Roghair Robert D. , Kiss Gabriella , Funke Simone , Bokor Szilvia , Molnár Dénes , Miseta Attila , Bódis József , Kovács Kálmán , Ertl Tibor
Published: March 2023

Background: Infants have three options for feeding: their own mother’s breast milk, donor milk, or infant formula. Insulin, testosterone, total protein, and albumin levels were measured in breast milk samples from the first 6 months of lactation, in donor milk samples, and in different infant formulas. Methods: Mothers who gave birth to term (n = 19) or preterm (n = 19) infants were recruited to collect breast milk samples during the first 6 months of lactation. The Breast Milk Collection Center (Unified Health Institution, Pécs, Hungary) provided 96 donor milk (DM) samples for analysis in our study. Insulin, testosterone, total protein, and albumin levels were measured in breast milk, donor milk, and infant formulas. Results: During the first 2 months of lactation, the concentration of insulin was lower (−27.4%) while the testosterone concentration was higher (+20.8%) compared to the period between the 3rd and 6th months only in the preterm breast milk samples. The infant formulas examined did not contain insulin or testosterone. Holder pasteurization (HoP) did not influence the level of testosterone in human milk, although HoP decreased the insulin (−53.6%) and albumin (−38.6%) concentrations. Conclusions: Diet impacts the hormone intake of infants, underlining the importance of breastfeeding and the possible supplementation of formula-fed infants.
Food Consumption of People with Sickle Cell Anemia in a Middle-Income Country
Authors: Teixeira Tamara Vilhena , Da Silva Ana Carolina Feldenheimer , Rodrigues Cláudia dos Santos Cople , Brito Flávia dos Santos Barbosa , Canella Daniela Silva , Citelli Marta
Published: March 2023

Sickle cell anemia (SCA) is a genetic and hemolytic disease globally characterized by social vulnerability. Food consumption has been insufficiently analyzed in SCA. Secondary iron overload is often observed. This leads to unreliable recommendations for dietary iron restriction. We assessed food consumption and iron intake among adults with SCA. Considering the guidelines for healthy eating, foods were grouped according to the NOVA classification. This transversal study included 74.4% of eligible patients who were registered in the reference center for SCA treatment in Rio de Janeiro, Brazil, in 2019. Data on food consumption were collected through 24 h recall. The monthly household income of 82.3% of patients was less than $770. The consumption of fresh or minimally processed foods was directly associated with monthly household income (p < 0.0001; η2 = 0.87). Ultra-processed foods provided more than one-third of the total energy intake (35.2%). The prevalence of inadequate iron intake was about 40% among women, while that of iron intake above the tolerable upper limit was 0.8%. People from lower socioeconomic classes had the lowest iron intake. Strategies to encourage the consumption of fresh or minimally processed foods are needed considering the requirement of an antioxidant diet in SCA. These findings highlight the need for health equity to ensure food security and healthy eating in SCA.
The Effects of 12 Weeks of Concurrent and Combined Training on Inflammatory Markers, Muscular Performance, and Body Composition in Middle-Aged Overweight and Obese Males
Authors: Bagheri Reza , Kargarfard Mehdi , Jalali Khosro , Ashtary-Larky Damoon , Cheraghloo Neda , Ghobadi Hamid , Moghadam Babak Hooshmand , Wong Alexei , Nordvall Michael , Dutheil Frédéric
Published: March 2023

Aim: Previous studies have focused on the order of endurance and resistance training when performing concurrent training (CT). However, no study has compared the effects of combined training with CT orders on inflammatory markers, muscular performance, and body composition in overweight and obese males. Therefore, the purpose of the current study was to compare the effects of 12 weeks of CT and combined training on the aforementioned markers in overweight and obese males. Methods: Sixty middle-aged overweight and obese males (age 51 ± 4 years) were randomly assigned into one of four groups: endurance followed by resistance training (ER; n = 15), resistance followed by endurance training (RE; n = 15), combined resistance and endurance training (COM), or control (CON; n = 15). Anthropometric, body composition, inflammatory marker, and muscular performance measurements were collected at baseline and after 12 weeks. Results: FFM remained unchanged in all three intervention groups (p > 0.05). Reductions in FM in the RE group were significantly greater than in CON (p = 0.038). The increases in serum concentrations of adiponectin in the RE group were significantly greater than in all other groups (p < 0.05). Increased serum concentrations of CTRP3 in all intervention groups were significantly greater than the CON group (p < 0.05); moreover, the increases in the RE group were significantly greater than CON (p < 0.001). Regarding CTRP5, the increase in RE was significantly greater than COM (p = 0.014). The RE group experienced significantly greater increases in CTRP9 than all other groups (p < 0.05), and the decreases in serum concentrations of CRP and TNF-α were significantly greater in the RE group compared to CON and ER (p < 0.05). Vo2max in the ER group was significantly greater than COM (p = 0.009), and all interventions resulted in higher gains compared to CON (p < 0.05). The increases in leg press strength, chest press strength, lower-body power, and upper-body power in the RE group were significantly greater than in the COM group (p < 0.05). In addition, the increases in chest press strength in the ER group were significantly greater than COM (p = 0.023). Conclusions: Regardless of training order, CT improved inflammatory markers, body composition, power, and VO2max. Notably, our analysis indicated significantly greater improvements in adiponectin, CTRP5, CTRP9, CRP, and TNF-α levels when RT preceded ET in CT sessions compared to other exercise training sequences. These findings suggested that the order of exercise training may have a significant impact on the effectiveness of CT on inflammatory markers, which has potential implications for exercise prescription and optimization of health-related training outcomes.