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Masoumeh Azimirad,1,* YoungJae Jo,2,* Min-Sueng Kim,2 Minsoo Jeong,2 Shabnam Shahrokh,3 Hamid Asadzadeh Aghdaei,4 Mohammad Reza Zali,3 Seungjun Lee,5 Abbas Yadegar,1 Jae-Ho Shin2 1Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 2Department of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea; 3Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 4Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 5Department of Food Science and Nutrition, College of Fisheries Science, Pukyong National University, Busan, Republic of Korea*These authors contributed equally to this workCorrespondence: Abbas Yadegar; Jae-Ho Shin Tel +98-21-22432518; +82 53-950-5716Fax +98-21-22432527; +82 53-953-7233Email babak_y1983@yahoo.com; jhshin@knu.ac.krBackground and Purpose: Fecal microbiota transplantation (FMT) has emerged for the therapeutic treatment of recurrent Clostridioides difficile infection (rCDI) with concurrent inflammatory bowel disease (IBD). As the first Iranian population cohort, we examined how gut microbiota and their functional profiles change in Iranian rCDI patients with underlying IBD before and after FMT.Patients and Methods: FMT was performed to eight IBD patients via colonoscopy. Profiles of gut microbiota from donors and recipients were investigated using 16S rRNA gene sequence analysis.Results: Patients experienced no IBD flare-ups or other adverse effects, and all recovered to full health. Moreover, all rCDI patients lacked the Bacteroidetes present in donor samples. After FMT, the proportion of Bacteroidetes increased until a normal range was achieved. More specifically, the relative abundance of Prevotella was found to increase significantly following FMT. Prevotella was also found to correlate negatively with inflammation metrics, suggesting that Prevotella may be a key factor for resolving CDI and IBD. Gut microbiota diversity was found to increase following FMT, while dysbiosis decreased. However, the similarity of microbial communities of host and recipients did not increase, and wide variation in the extent of donor stool engraftment indicated that the gut bacterial communities of recipients do not shift towards those of donors.Conclusion: FMT leads to significant alterations of the community structure of gut bacteria in rCDI patients with IBD. The change in relative abundance of Proteobacteria and bacterial diversity indicated that FMT promotes recovery from intestinal permeability and inflammation in rCDI patients. Moreover, strong negative correlation between Prevotella and inflammation index, and decreased dysbiosis index advocate that the improvement of CDI is possibly due to gut microbiome alteration. Collectively, our findings show that FMT would be a promising therapy to help reprogram the gut microbiome of Iranian rCDI patients with IBD.Keywords: fecal microbiota transplantation, Clostridioides difficile infection, inflammatory bowel disease, gut microbiome, functional profiles, gut dysbiosis

Masoumeh Azimirad,1 Abbas Yadegar,1 Fatemeh Gholami,1 Shabnam Shahrokh,2 Hamid Asadzadeh Aghdaei,3 Gianluca Ianiro,4 Hidekazu Suzuki,5 Giovanni Cammarota,4 Mohammad Reza Zali2 1Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 2Gastroenterology and Liver Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 3Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran; 4Digestive Disease Center, Fondazione Policlinico Universitario Agostino Gemelli IRCCS, Catholic University of Sacred Heart, Rome, Italy; 5Division of Gastroenterology and Hepatology, Department of Internal Medicine, Tokai University School of Medicine, Isehara, Kanagawa 259-1193, JapanCorrespondence: Abbas YadegarFoodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Shahid Arabi Ave., Yemen St., Velenjak, Tehran, IranEmail a.yadegar@sbmu.ac.irPurpose: Fecal microbiota transplantation (FMT) is an effective treatment option for patients with recurrent Clostridioides difficile infection (rCDI). However, there is a paucity of evidence regarding its efficacy and safety in patients with rCDI and concurrent inflammatory bowel disease (IBD). Here, we present a single-center experience of FMT for treatment of rCDI in Iranian patients with IBD.Patients and Methods: Eight patients with established IBD (7 with ulcerative colitis and 1 with Crohn’s disease) who underwent at least one FMT via colonoscopy for treatment of rCDI were enrolled in this study. Demographics, pre-FMT and post-FMT IBD activity, efficacy for rCDI and adverse events (AEs) were assessed during a 6-month follow-up period. All patients had experienced 3 episodes of rCDI and were refractory to conventional therapies with metronidazole and vancomycin. Primary cure and secondary cure rates were assessed after FMT treatments.Results: A total of 10 FMTs were performed via colonoscopy in 8 patients (6/8; 75% men) with a median age of 35 years (range: 22– 60). Two patients received a second FMT. Overall, the primary and secondary cure rates were 75% and 100%, respectively. Two patients developed CPE-producing C. perfringens diagnoses after second FMTs. There were no other AEs, and no patient experienced IBD flare.Conclusion: We demonstrated that FMT appears to be an effective, safe and rational therapeutic alternative for resolution of rCDI in patients with underlying IBD. Furthermore, we suggest implementing the CPE-producing C. perfringens testing in the screening of FMT donors.Keywords: fecal microbiota transplantation, recurrent Clostridioides difficile infection, inflammatory bowel disease, FMT, rCDI, IBD, Iran

Abstract This study optimizes CO2 adsorption using hydrochar from de-oiled flaxseed (FDOP), a waste byproduct of the oil extraction industry, through hydrothermal carbonization (HTC). The aim is to enhance CO2 capture sustainably and cost-effectively. Using Response Surface Methodology (RSM), in optimal conditions achieved 1153.26 mg/g CO2 adsorption capacity under 215.15 °C synthesis temperature, 3.05 h synthesis time, 0.99 M acid concentration, 8.997 bar pressure, and 25.07 °C adsorption temperature. Statistical analysis (F-value: 44.48, R²: 0.9705) confirmed strong model reliability. Kinetic analysis showed both physical and chemical adsorption, while thermodynamic analysis revealed exothermic behavior (ΔH° values: -46.697 kJ/mol for M-225, -40.230 kJ/mol for MA-203). After 10 regeneration cycles, the adsorption capacity was reduced by only 2.8% and 3.1%, indicating excellent recyclability. This study highlights FDOP-derived hydrochar as a highly efficient, low-cost adsorbent, offering industrial applications for carbon capture and waste management.

Abstract Carbon dioxide capture has become an important issue in reducing atmospheric heat these days. In this study, adsorption of carbon dioxide by aerogel Gamma Alumina-Metatitanic Acid has been investigated and optimized. Morphological and structural analyses such as BET, FESEM, FT-IR, and XRD have also been conducted. In addition, Response surface methodology has been applied in order to achieve the optimal conditions, using a five-level Central composite design. The highest amount of adsorption, 12.874 (mmol/g), was recorded at a temperature of 20 (°C), pressure of 7 (bar), and 25 (%wt) of Metatitanic Acid. This was approximately 11.46% and 4.84% higher than those of mesoporous MgO and 4Azeolite, respectively. Regeneration of the adsorbent was also studied at different temperatures and process durations. Metatitanic acid, as a catalyst, reduces the temperature and regeneration time of the adsorbent by creating active sites and surface hydroxyl groups. It also lowers the required activation energy and enhances the thermal conductivity of the composite material. The optimal result was achieved at a temperature of 100 (°C) and a duration of 30 (min). Finally, isothermal and thermodynamic experiments were conducted to establish the most accurate predictive model and conditions, including Enthalpy, Entropy, and Gibbs free energy. The results indicate that the Freundlich model aligned well with the laboratory findings. Additionally, the negative values of Enthalpy, Entropy, and Gibbs free energy suggested that the adsorption process was physical, exothermic, and spontaneous.

Abstract This research developed a novel composite of MOF-NH2 and graphene oxide (GO) for enhanced CO2 capture. Employing the response surface methodology-central composite design (RSM-CCD) for experiments design, various MOF-NH2/GO samples with GO loadings from 0 to 30 wt% were synthesized. The results of SEM, XRD, EDS, and BET analysis revealed that the materials maintained their MOF crystal structure, confirmed by X-ray diffraction, and exhibited unique texture, high porosity, and oxygen-enriched surface chemistry. The influence of temperature (25–65 °C) and pressure (1–9 bar) on CO2 adsorption capacity was assessed using a volumetric adsorption system. Optimum conditions were obtained at weight percent of 22.6 wt% GO, temperature of 25 °C, and pressure of 9 bar with maximum adsorption capacity of 303.61 mg/g. The incorporation of amino groups enhanced the CO2 adsorption capacity. Isotherm and kinetic analyses indicated that Freundlich and Fractional-order models best described CO2 adsorption behavior. Thermodynamic analysis showed the process was exothermic, spontaneous, and physical, with enthalpy changes of − 16.905 kJ/mol, entropy changes of − 0.030 kJ/mol K, and Gibs changes energy of − 7.904 kJ/mol. Mass transfer diffusion coefficients increased with higher GO loadings. Regenerability tests demonstrated high performance and resilience, with only a 5.79% decrease in efficiency after fifteen cycles. These findings suggest significant potential for these composites in CO2 capture technologies.

The flaxseed oil extraction process has been investigated and enhanced by applying Ultrasonic-Assisted Extraction (UAE), and Mixer-Assisted Extraction (MAE) methods in this study. Response Surface Methodology (RSM) was also utilized to find the optimal values of the extraction parameters. The optimal conditions for UAE were determined to be 42.7 min extraction time, 0.283 mm particle size, and 2.48 W/mL power intensity, achieving the oil yield of 94.56 %. For MAE, the optimal conditions were 54.5 min extraction time, 0.274 mm particle size, 21.1 °C temperature, and 0.74 W/mL agitation intensity, resulting in the oil yield of 96.73 %. RSM showed high reliability with R2 values above 0.99 for both methods. Gas Chromatography Flame Ionization Detector (GC-FID) analysis revealed that UAE and MAE resulted in higher unsaturated fatty acids concentrations (85.8 % and 86 %, respectively) compared to CPE (78.2 %). Kinetic studies indicated that UAE and MAE are more efficient in extracting unsaturated fatty acids, with MAE showing the highest double bond content. The Kinetic models demonstrated that extraction kinetics were controlled primarily by solid-phase resistance, with the washing coefficients being significantly higher than the diffusion coefficients. The Perez model calculated diffusion coefficients of 8.03 × 10⁻12 m2/s for UAE and 1.41 × 10⁻11 m2/s for MAE, activation energies of 16.44 kJ/mol for UAE and 15.64 kJ/mol for MAE.

This article presents a comprehensive study of CO2 capture using a new composite of Montmorillonite and Choline-Chloride-Urea in a continous fixed-bed adsorption system. The results revealed superior performance of a surface-activated mesoporous support compared to the unmodified solid support. The breakthrough curves, adsorption capacities, regenerability, and CO2/N2 selectivity of the developed nano-caly adsorbent were also studied for the first time. The ANOVA analysis indicated highly significant effects of gas flow rate and CO2 vol. % on breakthrough-time and adsorption capacity. The kinetic mathematical models were applied for breakthrough curve analysis. Clark model fitted to the experimental data better than others.

In various studies, researchers have utilised different solvents to extract sulfur compounds from the fuels. This paper introduces a novel magnetic deep eutectic solvent employed in the ultrasound-assisted oxidative desulfurisation of dibenzothiophene within a model fuel. The solvent, synthesised at 85°C by combining choline chloride, p-toluene sulfonic acid, and FeCl₃, underwent characterisation through Fourier transform-infrared, Vibrating-sample magnetometer, and Raman spectrometry. Exploration of the key parameters, including oxidant to model fuel volumetric fraction percentage (0.2–0.3), Iron (III) chloride to choline chloride mole fraction (0.1–0.3), and Magnetic deep eutectic solvent to model fuel volumetric fraction (0.2–0.3), was conducted to assess their impact on dibenzothiophene conversion rates. Employing response surface methodology based on central composite experimental design, optimal operational parameters for the ultrasound-assisted oxidative desulfurisation process were identified, resulting in a sulfur removal rate of 98.7%. The findings highlight the solvent sustained efficiency even at higher dibenzothiophene concentrations. Additionally, the solvent paramagnetic properties facilitated an expedited separation from the fuel, leading to the significantly reduced process times.

Abstract Background Ureteral cancer is a rare cancer. This study aimed to provide an up-to-date and comprehensive analysis on the global trends of ureteral cancer incidence and its association with lifestyle and metabolic risk factors. Methods The incidence of ureteral cancer was estimated from the Cancer Incidence in Five Continents Plus and Global Cancer Observatory databases. We analyzed the (1) global incidence of ureteral cancer by region, country, sex, and age group by age-standardized rates (ASR); (2) associated risk factors on a population level by univariable linear regression with logarithm transformation; and (3) incidence trend of ureteral cancer by sex and age group in different countries by Average Annual Percentage Change (AAPC). Results The global age-standardized rate of ureteral cancer incidence in 2022 was 22.3 per 10,000,000 people. Regions with higher human development index (HDI), such as Europe, Northern America, and East Asia, were found to have a higher incidence of ureteral cancer. Higher HDI and gross domestic product (GDP) and a higher prevalence of smoking, alcohol drinking, physical inactivity, unhealthy dietary, obesity, hypertension, diabetes, and lipid disorder were associated with higher incidence of ureteral cancer. An overall increasing trend of ureteral cancer incidence was observed for the past decade, especially among the female population. Conclusions Although ureteral cancer was relatively rare, the number of cases reported was rising over the world. The rising trends among females were more evident compared with the other subgroups, especially in European countries. Further studies could be conducted to examine the reasons behind these epidemiological changes and confirm the relationship with the risk factors identified.

Total knee arthroplasty (TKA) is a cornerstone in addressing knee joint disorders, significantly enhancing patients' quality of life. However, despite technological advancements, a comprehensive understanding of the dynamic stresses experienced by knee prostheses during daily activities, particularly under rehabilitation interventions, remains elusive. This study aims to bridge this gap by employing numerical simulations and finite element analysis to elucidate these dynamic stresses and their interaction with rehabilitation protocols.A real-life knee replacement prosthesis model was meticulously constructed through coordinate measuring and 3D scanning, facilitating detailed finite element analysis in ANSYS Workbench version 17.1. Two distinct boundary conditions and loading scenarios were applied, with comparisons made between linear and nonlinear material assumptions. The simulation results using these different boundary condition methods revealed minimal differences. Specifically, at a knee angle of 0°, the relative stress error rate between the two boundary condition types was approximately 1 % (1.11 MPa and 1.099 MPa, respectively). At 15° and 90°, the error rates were 1.9 % and 0.56 %, respectively (10.275 MPa and 10.078 MPa at 15°; 10.275 MPa and 10.078 MPa at 90°). Given these minimal differences, the first type of boundary condition was adopted for the subsequent scenarios to enhance convergence efficiency in the analysis.Moreover, comparative analyses between linear and nonlinear material behaviors demonstrated acceptable agreement, offering insights into potential efficiency gains in simulation methodologies. Building on this foundation, an optimized tibial model was proposed, incorporating geometric alterations to the tray. Quantitative assessments revealed significant reductions, with von Mises stress decreasing by 23.35 % and equivalent strain by 17 % at a knee angle of 140°. Further evaluations at varying angles, including 60°, consistently showed positive influences on stress and strain. These quantitative findings not only contribute valuable insights into the mechanical behavior of knee prostheses but also provide tangible evidence for the efficacy of linear material behavior assumptions. The proposed optimized model exhibits promising potential for enhancing the design and performance of knee prostheses, particularly under critical loading conditions.In conclusion, these results underscore the importance of a nuanced understanding of knee prosthesis behavior during rehabilitation, offering a quantitative foundation for refining existing designs and informing the development of next-generation prostheses.

Purpose: Regenerative medicine offers new techniques for osteoarthritis (OA) disorders, especially while considering simultaneous chondral and subchondral regenerations. Methods: Chitosan and hyaluronan were chemically bound as the chondral phase and the osteogenic layer was prepared with alginate and nano-hydroxyapatite (nHAP). These scaffolds were fixed by fibrin glue as a biphasic scaffold and then examined. Results: Scanning electron microscopy (SEM) confirmed the porosity of 61.45±4.51 and 44.145±2.81 % for the subchondral and chondral layers, respectively. The composition analysis by energy dispersive X-ray (EDAX) indicated the various elements of both hydrogels. Also, their mechanical properties indicated that the highest modulus and resistance values corresponded to the biphasic hydrogel as 108.33±5.56 and 721.135±8.21 kPa, despite the same strain value as other groups. Their individual examinations demonstrated the proteoglycan synthesis of the chondral layer and also, the alkaline phosphatase (ALP) activity of the subchondral layer as 13.3±2.2 ng. After 21 days, the cells showed a mineralized surface and a polygonal phenotype, confirming their commitment to bone and cartilage tissues, respectively. Immunostaining of collagen I and II represented greater extracellular matrix (ECM) secretion in the biphasic composite group due to the paracrine effect of the two cell types on each other. Conclusion: For the first time, the ability of this biphasic scaffold to regenerate both tissue types was evaluated and the results showed satisfactory cellular commitment to bone and cartilage tissues. Thus, this scaffold can be considered a new strategy for the preparation of implants for OA.

Syntheses of the acyclic amidinium salts, morpholinoformamidinium hexafluoridophosphate [OC4H8N—CH=NH2]PF6 or C5H11N2O+·PF6−, 1, and pyrrolidinoformamidinium hexafluoridophosphate [C4H8N—CH= NH2]PF6 or C5H11N2+·PF6−, 2, were carried out by heating either morpholine or pyrrolidine with triethyl orthoformate and ammonium hexafluoridophosphate. Crystals of 1 obtained directly from the reaction mixture contain one cation and one anion in the asymmetric unit. The structure involves cations linked in chains parallel to the b axis by N—H...O hydrogen bonds in space group Pbca, with glide-related chains pointing in opposite directions. Crystals of 1 obtained by recrystallization from ethanol, however, showed a similar unit cell and the same basic structure, but unexpectedly, there was positional disorder [occupancy ratio 0.639 (4):0.361 (4)] in one of the cation chains, which lowered the crystal symmetry to the non-centrosymmetric space group Pca21, with two cations and anions in the asymmetric unit. In the pyrrolidino compound, 2, cations and anions are ordered and are stacked separately, with zigzag N—H...F hydrogen-bonding between stacks, forming ribbons parallel to (101), extended along the b-axis direction. Slight differences in the delocalized C=N distances between the two cations may reflect the inductive effect of the oxygen atom in the morpholino compound.

In this study, CO2 capture using Hydrochar adsorbents synthesized from Cigarette Filter, specifically H-208 and HA-204, was rigorously investigated. Optimization using RSM was applied to fit a quadratic model to the data with F-value of 184.95 and R2 of 0.9847. H-208 and HA-204 display maximum CO2 adsorption capacities of 1028.35 mg/g and 1003.35 mg/g, respectively, at 9 bar and 25 °C. Isotherm studies ranked Freundlich and Sips models as effective descriptors, highlighting differences in adsorption behavior between HCs synthesized at different conditions. Kinetic modeling identified the Elovich model as suitable for predicting time-dependent CO2 adsorption. Thermodynamic analysis revealed differences in adsorbent affinity and spontaneity between HCs, with higher enthalpy values for H-208 indicating stronger adsorbent-adsorbate interactions. ΔH° values of −61.863 kJ/mol for H-208 and -47.442 kJ/mol for HA-204, signifying an exothermic adsorption process. The CO2 adsorption mechanism involves physical and chemical processes influenced by the polar structure, surface area, and functional groups of HCs. The effect of HCl on CO2 adsorption is insignificant, and the use of HCl only reduces the synthesis time. Adsorbent reusability tests showed minor capacity declines over multiple cycles, indicating their potential in environmental remediation and industrial gas separation processes.

In this study, a cheap, effective and stable catalyst has been applied to the extractive oxidative desulfurization (EODS) process for the first time. FT-IR, XRD, and FE-SEM techniques were used to investigate the structural characteristics of the catalyst. The process has also been optimized using RSM technique leading to 100 % dibenzothiophene (DBT) removal efficiency when reaction temperature, O/S ratio, catalyst dosage, and stirring speed were at 50 °C, 6, 0.09 g, and 2500 rpm, respectively. EODS process of this study has been 16 times faster and also less energy demanding than a reported aerobic oxidative desulfurization using the same catalyst.

This study investigates CO2 diffusion and Henry's coefficients in a packed column using ANN and RSM. The experimental setup involved circulating a NaOH solution through the packed column. A quadratic model in RSM analysis was employed for optimizing the parameters including liquid flow rate of 73.34, gas velocity of 1.957, temperature of 7.7, and packing's specific surface of 0.45. Multilayer perceptron (MLP) and radial basis function (RBF) models of ANN achieved regression coefficients (R2) exceeding 0.97, with mean squared error (MSE) below 0.0035. The MLP model, featuring three hidden layers (15, 10, 5 neurons) and 1191 epochs, exhibited an MSE of 0.003021, along with an average absolute relative deviation (AARD) of 0.0003 for DCO2 and 0.00001 for HCO2. Similarly, utilizing the Gaussian function with 50 neurons, the RBF model attained an MSE of 0.003544, with an optimal spread of 2. This study concludes that by effectively predicting DCO2 and HCO2 within specified ranges of operational parameters, efficient CO2 capture can be achieved, thereby contributing to advancements in CO2 capture technology.

In this study, we successfully utilized a green chemistry approach to prepare an adsorbent by functionalizing Montmorillonite with Choline Chlroride: Urea (a Deep Eutectic Solvent) to compare CO2, O2, and N2 adsorption. We conducted studies on the adsorption mechanism using a volumetric system at temperatures ranging from 25 to 55 °C under pressures of up to 9 bar. We assessed the effects of acid activation concentration, solvent concentration, and adsorbent mass on the CO2/O2 and CO2/N2 adsorption ratios (mg/mg). Characterization analyses confirmed that modification of interlayer spaces, ion exchange content, and Al/Si occurred through acid treatment and solvent impregnation. The CO2 adsorption mechanism demonstrated a heterogeneous multilayer and chemophysical sorption nature, which was in agreement with the Hill isotherm and Ellovich kinetic model. In contrast, the O2 and N2 mechanisms were in agreement with a monolayer nature, which matched the Langmuir isotherm and first-order kinetic model. We achieved the optimum adsorption ratio of CO2/O2 and CO2/N2 at 35 °C, while the highest individual adsorption for all three gases was obtained at 25 °C. At 35 °C, 5 bar, and 0.5 g, the highest uptake adsorption was 208.6 mg/g for CO2, 72.6 mg/g for O2, and 39.3 mg/g for N2. Thermodynamic parameters showed that the adsorption nature of CO2, O2, and N2 was exothermic (ΔH

In this paper, the damping of low-frequency oscillations (LFOs) in a power system containing Static VAR Compensator (SVC) is investigated based on Multiple-Model Linear Optimal Control (MMLOC) Strategy. The performance of MMLOC is enhanced using Polynomial Combination Algorithm (PCA). A linear optimal controller (LOC) generates the optimal control signal with linearization the nonlinear state equations of the system and solving the Riccati equation. One LOC generates synchronized control signals for the synchronous generator excitation system as well as SVC. The LOC is assigned to generate each model’s control signal. The final control signal is made by interpolating the LOC output signals obtained from each model using PCA. Considering a three-phase symmetrical fault on a near bus to the generator, the proposed control strategy is evaluated. This strategy not only maintains stability but also reduces LFO effectively. Furthermore, steady state error of rotor speed and rotor angle tend to zero favorably. Simulations are done for single- and multi-machine power systems via a MATLAB m-code.

Abstract Modified mesoporous NH2-Zr-BTC mixed ligand MOF nanocomposites were synthesized via the hydrothermal method as a novel adsorbent for CO2 capture. The newly modified MOF-808 with NH2 demonstrated a similar mesoporous morphology as MOF-808, whereas the specific surface area, pore volume, and average particle size, respectively, increased by 15%, 6%, and 46% compared to those of MOF-808. The characterization analyses exhibited the formation of more active groups on the adsorbent surface after modification. In addition, a laboratory adsorption setup was used to evaluate the effect of temperature, pressure, and NH2 content on the CO2 adsorption capacity in the range of 25–65 °C, 1–9 bar, and 0–20 wt%, respectively. An increase in pressure and a decrease in temperature enhanced the adsorption capacity. The highest equilibrium adsorption capacity of 369.11 mg/g was achieved at 25 °C, 9 bar, and 20 wt% NH2. By adding 20 wt% NH2, the maximum adsorption capacity calculated by the Langmuir model increased by about 4% compared to that of pure MOF-808. Moreover, Ritchie second-order and Sips models were the best-fitted models to predict the kinetics and isotherm data of CO2 adsorption capacity with the high correlation coefficient (R 2 > 0.99) and AARE% of less than 0.1. The ΔH°, ΔS°, and ΔG° values were − 17.360 kJ/mol, − 0.028 kJ/mol K, and − 8.975 kJ/mol, respectively, demonstrating a spontaneous, exothermic, and physical adsorption process. Furthermore, the capacity of MH-20% sample decreased from 279.05 to 257.56 mg/g after 15 cycles, verifying excellent stability of the prepared mix-ligand MOF sorbent.

As turbine entry temperatures of modern jet engines continue to increase, additional thermal stresses are introduced onto the high-pressure turbine rotors, which are already burdened by substantial levels of centrifugal and gas loads. Usually, for modern turbofan engines, the temperature distribution upstream of the high-pressure stator is characterized by a series of high-temperature regions, determined by the circumferential arrangement of the combustor burners. The position of these high-temperature regions, both radially and circumferentially in relation to the high-pressure stator arrangement, can have a strong impact on their subsequent migration through the high-pressure stage. Therefore, for a given amount of thermal power entering the turbine, a significant reduction in maximum rotor temperatures can be achieved by adjusting the inlet temperature distribution. This paper is aimed at mitigating the maximum surface temperatures on a high-pressure turbine rotor from a modern commercial turbofan engine by conducting a parametric analysis and optimization of the inlet temperature field. The parameters considered for this study are the circumferential position of the high-temperature spots, and the overall bias of the temperature distribution in the radial direction. High-fidelity unsteady (phase-lag) and conjugate heat transfer simulations are performed to evaluate the effects of inlet clocking and radial bias on rotor metal temperatures. The optimized inlet distribution achieved a 100 K reduction in peak high-pressure rotor temperatures and 7.5% lower peak temperatures on the high-pressure stator vanes. Furthermore, the optimized temperature distribution is also characterized by a significantly more uniform heat load allocation on the stator vanes, when compared to the baseline one.

Abstract The thermal conductivity and stability of nanofluids pose challenges for their use as coolants in thermal applications. The present study investigates the heat transfer coefficient (HTC) of an Al12Mg17 nanofluid through the utilization of a novel beam displacement method. The study also examines the nanofluid's stability, particle size distribution (PSD), TEM micrograph, and electrical conductivity. From three distinct categories of surfactants, a particular surfactant (CTAB) was chosen to disperse Al12Mg17 nanoparticles in DI water, and subsequently, a two-step method was employed to generate the nanofluid. Dispersion stability is visually monitored and quantified with a zeta potential test. HTC and PSD are measured using optical setups. To evaluate the results, the HTC obtained from the beam displacement method is compared with that of the KD2 Pro apparatus, and the PSD findings are analyzed through TEM micrographs. The results show that a 0.16 vol.% CTAB is the maximum stability for 0.025 vol.% Al12Mg17 nanofluid properly. The optimum ultrasonication period is 2 h, yielding a peak PSD of 154 nm. Increasing nanoparticle concentration enhances HTC up to 40% compared to the base fluid at 0.05 vol.%. Electrical conductivity increases linearly from 155 to 188 μ $${\rm S}/\mathrm{cm}$$ S / cm with nanoparticle concentration. Optical methods for measuring HTC in nanofluids offer the advantage of early results, prior to bulk motion. Thus, the application of nanofluids in thermal systems necessitates the development of optical techniques to improve accuracy.

Abstract Background and Objective: The objective of this study was to assess antimicrobial effects of silver nanoparticles on Gram-positive and Gram-negative bacteria that used in preparing silver nanocomposite with the antibacterial characteristics using solution method. Moreover, the aim of the current study was to produce antimicrobial silver nanocomposites for food coating with their effects on a wide range of bacteria. Material and Methods: To assess antibacterial characteristics of silver nanoparticles, several steps were carried out. First, nanoparticles were synthesized through a chemical reduction method using NaBH4 and then analyzed using x radiation diffraction, ultraviolet and visible spectroscopic analysis, dynamic light scattering and scanning electron microscopy nanometric assays. Then, Staphylococcus aureus and Escherichia coli were used as Gram-positive and Gram-negative bacterial indicators. Minimum inhibitory concentration, minimum bactericidal concentration and inhibition zone levels were measured. Nanocomposite was produced using solution blending method and its antibacterial characteristics were assessed using inhibition zone method. Results and Conclusion: Results indicated that silver nanoparticles with 20 and 50 µg.l-1 concentrations included inhibitory effects on Staphylococcus aureus and Escherichia coli, respectively. Furthermore, concentrations of 40 to 60 mg.l-1 included lethal effects on Staphylococcus aureus and Escherichia coli, respectively. Based on the results, the highest antibacterial effects were observed on Gram-positive Staphylococcus aureus. In inhibition zone assays, a 3-5 mm zone was seen around the silver nanoparticle discs in cultures of the microorganisms. In the inhibition zone assay of the produced nanocomposites, the zone was expected regarding the concentrations. Results were calculated in three repetitions and the value estimated through ANOVA was significant when p

Hydrogels use three-dimensional polymer networks with transverse connections as their technology to absorb water or biofluids. Water, as a fundamental component, significantly affects the functionality of biomedical polymers, including hydrogels. The molecular organization of water within hydrogels and its state (limited, medium, or free) were significant factors in biocompatibility and compatibility. If hydrophilic monomers are directly used to produce the product, the manufactured product will have poor mechanical properties. Consequently, it is critical to conduct research on the mechanical properties of hydrogels, as well as methods for increasing them. This study examined the interactions between polyacrylamide hydrogel and water molecules by studying the effect of different volume fractions (5–15 %) of polyacrylamide hydrogel on the mechanical properties (Young's modulus and ultimate strength) using molecular dynamics simulation. The results show that the potential and total energy in the sample converged to −43 and 12488 kcal/mol. The ultimate strength of sample was 0.0333 MPa. The Young's modulus calculated for polyacrylamide was 0.0009 MPa. By increasing the atomic ratio of structure in the range of 5 % to 15 %, the ultimate strength value increased from 0.0333 MPa to 0.0425 MPa. The value of Young's modulus reached its maximum, from 0.0009 MPa to 0.0014 MPa.

IntroductionUnderstanding the immune status of an individual using neutralizing antibody testing is complicated by the continued evolution of the SARS-CoV-2 virus. Previous work showed that assays developed against the wildtype strain of SARS-CoV-2 were insufficient predictors of neutralization of omicron variants, thus we developed an omicron-specific flow cytometry-based neutralizing antibody test and performed experiments to assess how well it compared to an omicron-specific PRNT assay (gold standard) and whether it could predict neutralizing activity to more recent omicron subvariants such as XBB.1.5.MethodsAccuracy of a novel flow cytometry-based neutralizing antibody (FC-NAb) assay was determined by comparison with an omicron-specific PRNT assay. A series of samples were evaluated in both the omicron FC-NAb assay and a second test was designed to assess neutralization of XBB.1.5.ResultsGood concordance between the omicron FC-NAb test and the omicron PRNT was demonstrated (AUC = 0.97, p

Due to increasing concerns about global warming regarding CO2 release to the atmosphere, various methods are used to capture CO2, among which chemical absorption via amine mixture solutions is very well developed. A set of 179 data related to CO2 absorption in a mixture, including a physical absorbent (sulfolane) and a chemical absorption (AEEA) in a wide range of temperature, pressure and solvent concentration is used to develop two Artificial Neural Networks (ANN). In Multi-Layer Perceptron (MLP), the Levenberg-Marquardt method is used to train the network. Most important factors such as regression analysis value (R2) of 0.99963, Mean Squared Error (MSE) value of 1.22E-05 and Average Absolute Relative Deviation value (%AARD) of 0.2671 factors reveal that the MLP network has a high capability to predict CO2 loading (αCO2). Also, a Radial Basis Function (RBF) network was developed. RBF network with a spread value of 2.2 and 138 neurons had an outstanding performance and achieved an MSE value of 2.53E-05 along with an R2 value of 0.99993, 11 seconds, and a %AARD value of 0.1460. According to experimental and predicted data, the neural networks are well trained and are able to predict CO2 loading precisely in an economic and optimized way.

The technology of hydrogels is three-dimensional polymer networks with transverse connections that can adsorb water or biofluids. These compounds can adsorb water without dissolving. Natural hydrogels are considered due to their variety, abundance, cheapness, non-toxicity, and biocompatibility with synthetic hydrogels. In this research, the effect of three types of cross-linked hydrogels polyacrylamide (PAM), polyvinyl alcohol (PVA), and polyethylene glycol (PEG) hydrogels), and volume fraction (5–15%) of PAM on the swelling, and thermal behavior (TB) of simulated samples were studied using molecular dynamics (MD) simulations. The results show that among the simulated hydrogels, the structure of PAM had better atomic behavior and TB. PAM hydrogel had the highest swelling, heat flux (HF), and thermal conductivity (TC), with a numerical value of 342,722 Å3, 1583 W/m2, and 0.57 W/m.K after 10 ns. In the following, by increasing the volume fraction of PAM hydrogel from 5% to 15%, swelling increased to 377,986 Å3, and the TC with 10% of PAM increased from 0.53 (W/m.K) to 0.66 (W/m.K). Furthermore, HF of the sample with 15% of PAM was increased from 1423 (W/m2) to 1761 (W/m2) after 10 (ns). Consequently, by increasing the volume fraction of PAM hydrogel, TB of simulated structure was improved.

Abstract Background Tissue engineering for cartilage regeneration has made great advances in recent years, although there are still challenges to overcome. This study aimed to evaluate the chondrogenic differentiation of human adipose-derived mesenchymal stem cells (hADSCs) on three-dimensional scaffolds based on polyglycerol sebacate (PGS) / polycaprolactone (PCL) / gelatin(Gel) in the presence of Nanohydroxyapatite (nHA). Materials and methods In this study, a series of nHA-nanocomposite scaffolds were fabricated using 100:0:0, 60:40:0, and 60:20:20 weight ratios of PGS to PCL: Gel copolymers through salt leaching method. The morphology and porosity of prepared samples was characterized by SEM and EDX mapping analysis. Also, the dynamic contact angle and PBS adsorption tests are used to identify the effect of copolymerization and nanoparticles on scaffolds' hydrophilicity. The hydrolytic degradation properties were also analyzed. Furthermore, cell viability and proliferation as well as cell adhesion are evaluated to find out the biocompatibility. To determine the potential ability of nHA-nanocomposite scaffolds in chondrogenic differentiation, RT-PCR assay was performed to monitor the expression of collagen II, aggrecan, and Sox9 genes as markers of cartilage differentiation. Results The nanocomposites had an elastic modulus within a range of 0.71–1.30 MPa and 0.65–0.43 MPa, in dry and wet states, respectively. The PGS/PCL sample showed a water contact angle of 72.44 ± 2.2°, while the hydrophilicity significantly improved by adding HA nanoparticles. It was found from the hydrolytic degradation study that HA incorporation can accelerate the degradation rate compared with PGS and PGS/PCL samples. Furthermore, the in vitro biocompatibility tests showed significant cell attachment, proliferation, and viability of adipose-derived mesenchymal stem cells (ADMSCs). RT-PCR also indicated a significant increase in collagen II, aggrecan and Sox9 mRNA levels. Conclusions Our findings demonstrated that these nanocomposite scaffolds promote the differentiation of hADSCs into chondrocytes possibly by the increase in mRNA levels of collagen II, aggrecan, and Sox9 as markers of chondrogenic differentiation. In conclusion, the addition of PCL, Gelatin, and HA into PGS is a practical approach to adjust the general features of PGS to prepare a promising scaffold for cartilage tissue engineering. Graphical Abstract

Abstract Background Periodontal regeneration, treatment of periodontal-related diseases and improving the function of implants are global therapeutic challenges. The differentiation of human stem cells from apical papilla into cementoblasts may provide a strategy for periodontitis treatment. This study aimed to evaluate the differentiation of primary human stem cells apical papilla (hSCAPs) to cementoblast cells. Material and methods SCAPs cells were isolated from human third molar and then incubated for 21 days in a differentiation microenvironment. Alkaline phosphatase (ALP) and Alizarin red S staining assays were performed to evaluate the calcium deposition and formation of hydroxyapatite in the cultured hSCAPs microenvironment. Real-time polymerase chain reaction (RT-PCR) assay was performed for cementum protein 1 (CEMP1), collagen type I (COL1), F-Spondin (SPON1), osteocalcin (OCN), and osteopontin (OPN) as specific markers of cementoblasts and their progenitors. Results ALP phosphatase activity in day 21 of treatment demonstrated a significant increase in ALP compared to the control. Alizarin red S staining assay showed that the differentiated hSCAPs offered a great amount of calcium deposition nodules compared to the control. The increased expression level of CEMP1, OCN, OPN, COL1 and Spon1 was observed in days 7, 14 and 21 compared to the control, while greatest expression level was observed in day 21. Conclusion In conclusion, the differentiation microenviroment is convenient and useful for promoting the differentiation of hSCAPs into cementoblast.

Abstract Objective To evaluate the relationship between pre‐operative PSA value, 68Ga‐prostate‐specific‐membrane‐antigen (PSMA) PET performance and oncologic outcomes after salvage lymph node dissection (sLND) for biochemical recurrent prostate cancer (PCa). Patients and methods The study included 164 patients diagnosed with ≤2 pelvic lymph‐node recurrence(s) of PCa documented on 68Ga‐PSMA PET scan and treated with pelvic ± retroperitoneal sLND at 11 high‐volume centres between 2012 and 2019. Pathologic findings were correlated to PSA values at time of sLND, categorized in early (1.5 ng/ml). Clinical recurrence (CR)‐free survival after sLND was calculated using multivariable analyses and plotted over pre‐operative PSA value. Results Median [interquartile range (IQR)] PSA at sLND was 1.1 (0.6, 2.0) ng/ml, and 131 (80%) patients had one positive spot at PET scan. All patients received pelvic sLND, whereas 91 (55%) men received also retroperitoneal dissection. Median (IQR) number of node removed was 15 (6, 28). The rate of positive pathology increased as a function of pre‐operative PSA value, with highest rates for patients with pre‐operative PSA > 1.5 ng/ml (pelvic‐only sLNDs: 84%; pelvic + retroperitoneal sLNDs: 90%). After sLND, PSA ≤ 0.3 ng/ml was detected in 67 (41%) men. On multivariable analyses, pre‐operative PSA was associated with PSA response (p

This study examined the effects of land-use changes on heavy metal pollution in runoff in a catchment of Tehran, Iran. Urban runoff samples were collected from six stations, including five various land uses and mixed land uses. The event mean concentration (EMC) was applied to determine heavy metals, including mercury (Hg), arsenic (As), cadmium (Cd), zinc (Zn), lead (Pb), and copper (Cu), in five land uses. Sampling was done during six events with different antecedent dry days (ADDs) during 2019–2020. The result revealed higher heavy metal concentrations in runoff in the industrial land use compared to other land-use types in the catchment. The calculated EMC rates were as follows: EMC Zn > EMC Pb > EMC Cu > EM As > EMC Hg > EMC Cd. This study also found that the maximum and minimum EMCs of heavy metals were associated with rainfall events with 115 and 1 dry days, respectively. In comparison to other heavy metals, mercury and arsenic were at a higher level in runoff as determined by EMC data analysis. In order to minimize the risk of heavy metal contamination of runoff, the relocation of industrial land uses from urban environments to non-urban areas is recommended. HIGHLIGHTS Event mean concentrations (EMCs) of heavy metals for typical land uses in a high-density urban area were assessed.; Heavy metal concentrations are higher in runoff in the industrial land use compared to other land-use types.; The calculation of the EMC rate showed that, in general, EMC Zn > EMC Pb > EMC Cu > EM As > EMC Hg > EMC Cd.; The heavy metal pollution load meaningfully increased in the urban runoff in dry seasons.;

Key Clinical Message In order to early diagnose and prevent the infection dissemination in both suspected solid organ donors and recipients after transplantation, pretransplantation screening tests for rare etiologies like Cryptococcus neoformans should be necessitated, as they can affect many vital organs, especially the brain, liver, and lungs. Abstract Cryptococcosis is a systemic fungal infection mainly affecting immunocompromised patients. The infection is occasionally seen in 16–21 months after organ transplantation, while early involvement is uncommon within

Abstract This paper proposes a two‐layer method for restoring service. Firstly, a new strategy is used to obtain binary variables relating to closed switches and tie switches. In addition, after the fault occurs it is also possible to obtain optimal islands online. Secondly, a non‐linear model is solved to optimally determine the islands created in the first step, in which distributed generation resources (DGRs), energy storages (ESs) and load shedding (LSH) are reprogrammed. When LSH is performed, the sensitive loads must experience the least amount of outage possible. Therefore, the loads are categorized into residential, industrial, and sensitive categories. In order to demonstrate the validity and effectiveness of the proposed method, a modified IEEE 33‐bus system is simulated. In simulations, the proposed strategy has been compared with one of the important existing methods. Based on these results, the proposed method can reduce the cost function by modifying the critical load less than other methods. In this method, the critical LSH is 220 kW, which is 105 kW less than the compared method. By reducing the amount of load, 46,000 dollars have been saved in system expenses. The results confirm that the proposed strategy is considerably superior to the existing method.

In this paper, a reconfigurable slot antenna capable of tuning a full octave in frequency from 2 GHz to 4 GHz is presented. The design is based on changing the capacitive loading of a slot antenna by physically displacing a metal plate connected to a piezoelectric linear actuator that changes the apparent electrical length of the antenna. The antenna was simulated, fabricated, and measured to tune across the 2–4 GHz frequency range while maintaining a maximum return loss of greater than 9.0 dB. Simulations also show a 65.74% to 95.75% radiation efficiency across S-band. A broadside realized gain of greater than 1.73 dB was measured over the entire tuning range. Moreover, the tuning mechanism was proven robust above other methods by withstanding up to 100 W of power incident on the feed at 3 GHz.

Duration and severity are the two main variables used in drought analysis. The copula functions are appropriate for multivariate drought analysis, as it lacks the limitations of the classical multivariate distribution function. This study investigated the bivariate frequency analysis of drought duration and severity of Yazd city in Iran synoptic station during 1953–2013. To this end, first, the drought duration and severity variables were derived from the 6-month Standardized Precipitation Index. Then, considering the distribution functions, the gamma distribution function was selected for analyzing the severity and the exponential distribution function was selected for analyzing the duration and then the Clayton copula function was selected out of the three copula functions as the most appropriate one. After conducting bivariate frequency analysis, the joint seasonal and conjunctive return period and conditional return period curves were plotted. The current study well signified that multivariate analyses could present better interpretations of the reality; for example, as it was identified in conditional return period curves of the drought, for every constant duration, the amount of the return period changed as the severity changed. On the contrary, in analyzing the univariate of duration, no effects of severity were observed. HIGHLIGHTS Use of multivariate analysis in research due to the high degree of correlation between the severity and duration of drought.; Accurate study of the correlation between the two parameters of hardness and duration of drought.; Using copula functions in this study that removes the limitations of classical distribution functions.; Calculation of 6 months.; Estimation of the parameters of the coupling function.;

This paper proposes a new control strategy based on multimodel linear optimization control (MMLOC) to damp power system low-frequency oscillations (LFO) faster. The multimodel control strategy is used to anticipate synchronous generator dynamic behavior and linear optimization control for generating a control signal uncomplicatedly. The third-order model of synchronous machine is considered for each of the models. The probability of each model’s validity is evaluated from the difference between model outputs and the same actual power system outputs via the Bayesian approach. To improve the postfault dynamics of the case study power system, which contains a static VAR compensator, a linear optimal controller (LOC) is designed. The 8th order model of the machines is used in simulations to represent the plant as accurately as possible.