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Background: Diminished ovarian reserve (DOR) is a condition that affects fertility by reducing the reproductive potential of the ovary. The altered expression profile of cumulus cells (CCs) can negatively affect the quality and quantity of oocytes in the ovaries. Recent studies suggest that circulating miRNAs play a significant role in the ovary function, and their serum expression changes can be valuable biomarkers for predicting ovarian function. Objective: Investigating the expression levels of circulating miRNA-4463 and its target cytochrome P450 19A1 gene (CYP19A1) in DOR-CCs in order to find a molecular pathway involved in DOR. Materials and Methods: In this case-control study, a total of 20 DOR-women and 20 women with normal ovarian reservation aged between 20-34 yr referred to Yazd Reproductive Science Institute, Yazd, Iran were included in the study. Serum and CCs were collected, and real time-polymerase chain reaction was performed to investigate the expression level of miR-4463, and its target gene CYP19A1. Results: Our results showed an inverse relationship between miR-4463 and CYP19A1 expression levels. Therefore, the increase in the expression of miR-4463 was significantly evident in DOR-women compared to the control group (p = 0.0019), while the expression of its target gene, CYP19A1, has significantly decreased in these women (p = 0.001). Conclusion: The present study suggests that miR-4463 and CYP19A1 pathways could regulate ovary function. Therefore, examination of this miRNA could be a promising parameter for predicting ovarian reserve and their response to stimulation protocols. [ABSTRACT FROM AUTHOR]

Modification of photocatalysts to improve their adsorption and photocatalytic activity in the oxidative desulfurization of liquid fuels has been reported by many investigators. In this study, Pt-decorated carbon-doped TiO2 nanoparticles were synthesized by hydrothermal and photo-deposition techniques and were subsequently used in photocatalytic oxidative desulfurization of dibenzothiophene (DBT) in n-heptane as a simulated liquid fuel with methanol as the extracting solvent. Carbon-doped TiO2 was first synthesized by a simple self-doping method. Pt was then loaded by a photo-deposition technique. The synthesized photocatalysts (labeled as YPt-CT where Y is percent Pt loading) were characterized by of X-ray diffraction (XRD), photoluminescence (PL), field emission scanning electron microscopy (FESEM), N2-physisorption, UV-Vis diffusive reflectance spectra (UV-Vis DRS), transmission electron microscopy (TEM), Fourier transform infrared spectra (FTIR), and nitrogen sorption measurements. The removal efficiency of DBT was 98% in the presence of 2 g/l of 0.5Pt-CT catalyst under visible-light irradiation (λ > 400 nm), ambient pressure, and reaction temperature of 40°C. [ABSTRACT FROM AUTHOR]

Solar water heaters represent a crucial component of sustainable energy systems, offering the potential to reduce energy costs and limit carbon emissions. This study focuses on the investigation of energy and exergy efficiency enhancement in evacuated tube solar water heaters deployed in the hot climate of Dezful, Iran. Specifically, the study evaluates the impact of engine-oil as a circulation fluid within copper U-tubes positioned inside evacuated tubes, with the addition of TiO2 nanoparticles in two concentrations (0.2 mass% and 0.4 mass%). Additionally, the study assesses the effectiveness of a metallic twisted tape insert within the U-tubes to augment the heat transfer rate, with the aim of improving the overall efficiency and performance of the system. In the assessments, the thermal efficiency diagram was divided by three phases and the behavior of each one was elaborated. As results, employing metallic-insert leads to 1.5 °C more water temperature. Moreover, 5.6 °C difference between 0.4 mass% TiO2 + insert and the base case was observed in the evening which results in 24.4% and 25.52% higher thermal efficiency and exergy efficiency, respectively. [ABSTRACT FROM AUTHOR]

Heat transfer enhancement in thermal systems is one of the most important efforts of researchers. Adding nanoparticles to circulating fluid is an effective way to increase the heat transfer rate, while its effect on pressure drop may be positive or negative in various cases. In this paper, both thermal and hydrodynamic aspects of flowing a TiO2/water nanofluid were considered with concentrations of 0.05, 0.1, 0.2, 0.5, and 1 mass percentages. The nanofluid was streamed through a helical coiled path, under a constant heat flux and different flow rates. The thermal characteristics are followed by calculations of Nusselt number (Nu), convective heat transfer coefficient, and heat transfer enhancement (HTE%). Accordingly, the utmost increase in Nusselt number was found as 29.8 and 36.5% for the concentration of 1 mass%, in laminar and turbulent flows, respectively. The pressure drop was assessed by means of friction factor and drag reduction percentage (DR%), so that in the lowest concentration and the lowest Reynolds number, the maximum DR% occurred as 6.4%. To have a better understanding of the system, the pumping power is reported against HTE% amounts. [ABSTRACT FROM AUTHOR]

Energy optimization is of vital importance especially in oil, gas and petrochemical industries. Distillation column with high energy consumption is one of the most common equipment in the aforementioned industries. Thus, it is important to revise the projection of initial process, reduce energy consumption and recover some of used energy. In this work, we studied energy optimization of a naphtha treating unit in a petrochemical company using Aspen HYSYS software. For energy optimization, feed temperature was changed to a satisfactory temperature (47 °C) for condensation of overhead steam distillation. Feed was used as a cooling fluid in the heat exchanger before the main condenser. According to outcome, 644.11 MW of energy was recovered and approximately 53% less energy was used in the air conditioner. Feed was injected in tower with higher temperature (212 °C) because of preheating. This reduces consumed energy up to approximately 63% by reducing the entering flow rate of reboiler.

The world is inconceivable without an everlasting demand for energy. Nowadays, various kinds of renewable energies, such as solar energy, are developing rapidly, since they have the least negative environmental impacts. Irradiation intensity is one the most important parameters in photovoltaic (PV) technology, and so integration of mirrors with a PV module can improve its performance. Mounting mirrors increases the radiation intensity but, at the same time, raises the surface temperature, which in turn reduces the electrical efficiency. The novelty of this study is keeping the cell temperature low despite receiving more radiation by installing 10 aluminum fins on the back of the panel. All tests were experimentally performed in the hot climate of Dezful, Iran. As a result, the best tilt angle of the mirror was found at 30°, where the output power was enhanced by 3.3% and electrical efficiency was reduced by 0.5% compared with the conventional case. When aluminum fins were added as heat sinks, both output power and electrical efficiency were enhanced by 11.4% and 13.1%, respectively. Moreover, comprehensive discussions on both energy and exergy are provided. The entropy generation was also calculated and accordingly, the case of PV 30 + fin generates 1.6% less entropy than the base one. [ABSTRACT FROM AUTHOR]

The purpose of this study was to use Henna as a biosorbent to remove lead ions (Pb2+) from an aqueous environment as an effective method for wastewater treatment. Dried leaves of Henna were ground and then passed through the standard screens to be used for the treatment process. The effects of main operating conditions, that is, time (20–200 min), biosorbent amount (0.1–1.2 g/L), and pH (2–9) on the percentage of removal of Pb2+ ions from aqueous solution using Henna were investigated. Maximum Pb2+ biosorption reached 90% at pH 5.5, 55 ppm initial concentration of Pb2+ ions, 1 g/L biosorbent amount, and 110 min time. Properties of biosorbent (before and after biosorption process) were characterized by Fourier-transform infrared spectroscopy and scanning electron microscopy. The Freundlich and Langmuir isotherm models were used to represent biosorption mechanisms so that the results of the Langmuir model with R² = 0.9473, are in better agreement with experimental data. Thermodynamic study indicates the biosorption process is exothermic in nature and thermodynamic parameters, ΔH = –25.16 (kJ/mol) and ΔS = +55.146 (J/mol K) were obtained. Kinetic studies were undertaken to determine the biosorption mechanism. The R² value of the pseudo-second-order kinetic model was found close to unity (R² = 0.994) indicating that the outcomes can adapt to this model better than a first-order kinetic model with R² = 0.923. The most important impact of using Henna is the high performance for the removal of the Pb2+ ions (90% removal efficiency) as the possible reason is due to its irregular surface structures and its availability and low price. [ABSTRACT FROM AUTHOR]

The mortality and morbidity rates for prostate cancer have recently increased to alarming levels, rising higher than lung cancer. Due to a lack of drug targets and molecular probes, existing theranostic techniques are limited. Human LIN28A and its paralog LIN28B overexpression are associated with a number of tumors resulting in a remarkable increase in cancer aggression and poor prognoses. The current review aims to highlight recent work identifying the key roles of LIN28A and LIN28B in prostate cancer, and to instigate further preclinical and clinical research in this important area. [ABSTRACT FROM AUTHOR]

In this study, lead ion biosorption from aqueous environment was investigated in a batch system using wheat stem and different lead ion concentrations (2.5-20 ppm), pH (2-8), mixing rates (280-360 rpm), biosorbent amounts (0.2-1 g), and contact times (10-180 min). The Freundlich, Langmuir, Temkin, and Dubinin-Radushkevich isotherm models were applied as adsorption isotherms. Kinetic studies (pseudo-first-order, pseudo-second-order, and intraparticle diffusion models) were undertaken to determine the biosorption mechanism. It is concluded that the wheat stem is a good choice for lead ion removal from aqueous solutions considering its high performance, abundance, and affordability. [ABSTRACT FROM AUTHOR]

Enhancing heat transfer rates while concurrently reducing pressure drop will significantly enhance the energy efficiency of industrial heat exchangers, thereby contributing to a cleaner and more sustainable environment in the future. This study explores the fluid flow of a novel combination solution in a helical heat exchanger under a constant heat flux across various Reynolds numbers (5000–17000) aiming to uncover synergies that enhance heat transfer efficiency while reducing drag for the first time. Two key performance metrics, namely Drag Reduction (DR) and Heat Transfer Enhancement (HTE), along with the thermal effective index, are introduced to evaluate both hydrodynamic and thermal characteristics. Under turbulent conditions, an aqueous solution containing Anionic PAM (100–500 ppm) obtains a noteworthy 43% DR at 500 ppm. Simultaneously, a colloidal solution of nano-SiO2 (500–3000 ppm) in deionized water demonstrates an impressive 47% HTE at 2000 ppm. Furthermore, this study introduces two novel terms, “heat transfer enhancement synergy” and “drag reduction synergy,” marking their debut in the literature. The investigation extends to exploring four Nano-SiO2_PAM combinations which is the novelty of the study, revealing an outstanding 93.3% synergy in HTE. Precisely, at Reynolds 14,000, the synergy between 100 ppm PAM and 2000 ppm SiO2 (named comb.20 as the best combination) attains a remarkable 73.76% in DR, showcasing a noteworthy thermal effectiveness reaching approximately 200%. Even for comb.20, at Reynolds 5000, the synergy achieves a notable 133.33% in DR and 76.22% in HTE, which is quite significant. This result is attributed to a complex formation that elongates the polymer chain due to the presence of nanoparticles around the polymer chain, effectively damping eddies. Furthermore, a novel set of correlations is proposed for the prediction of the Nusselt number of the aforementioned solutions, demonstrating a remarkable agreement with experimental data with a maximum error of 24%.Graphical Abstract: Enhancing heat transfer rates while concurrently reducing pressure drop will significantly enhance the energy efficiency of industrial heat exchangers, thereby contributing to a cleaner and more sustainable environment in the future. This study explores the fluid flow of a novel combination solution in a helical heat exchanger under a constant heat flux across various Reynolds numbers (5000–17000) aiming to uncover synergies that enhance heat transfer efficiency while reducing drag for the first time. Two key performance metrics, namely Drag Reduction (DR) and Heat Transfer Enhancement (HTE), along with the thermal effective index, are introduced to evaluate both hydrodynamic and thermal characteristics. Under turbulent conditions, an aqueous solution containing Anionic PAM (100–500 ppm) obtains a noteworthy 43% DR at 500 ppm. Simultaneously, a colloidal solution of nano-SiO2 (500–3000 ppm) in deionized water demonstrates an impressive 47% HTE at 2000 ppm. Furthermore, this study introduces two novel terms, “heat transfer enhancement synergy” and “drag reduction synergy,” marking their debut in the literature. The investigation extends to exploring four Nano-SiO2_PAM combinations which is the novelty of the study, revealing an outstanding 93.3% synergy in HTE. Precisely, at Reynolds 14,000, the synergy between 100 ppm PAM and 2000 ppm SiO2 (named comb.20 as the best combination) attains a remarkable 73.76% in DR, showcasing a noteworthy thermal effectiveness reaching approximately 200%. Even for comb.20, at Reynolds 5000, the synergy achieves a notable 133.33% in DR and 76.22% in HTE, which is quite significant. This result is attributed to a complex formation that elongates the polymer chain due to the presence of nanoparticles around the polymer chain, effectively damping eddies. Furthermore, a novel set of correlations is proposed for the prediction of the Nusselt number of the aforementioned solutions, demonstrating a remarkable agreement with experimental data with a maximum error of 24%. [ABSTRACT FROM AUTHOR]

Local velocities of bubbles rising in four different nanosilica solutions were investigated experimentally. Also, the density, viscosity, and surface tension of fumed nanosilica and modified nanosilica solutions were measured. Heat treatment and chemical functionalization were used to modify the properties of silica nanoparticles. It was found that the addition of nanosilica affected the hydrodynamics of the rising bubble by increasing the drag friction at the interface. However, environmentally responsive nanosilica particles behaved like surfactant molecules, due to the interfacial activity of hydrophilic and hydrophobic chains. Silica nanoparticles coated with both hydrophilic and hydrophobic agents had a stronger effect on the interfacial properties than those coated only with the hydrophobic agent. [ABSTRACT FROM AUTHOR]

The low temperature absorption method is currently used in a gas-processing unit to control the natural gas dew point. The major problem of this unit is the simultaneous absorption of high amount of methane within heavier hydrocarbons, which leads to low purity of ethane and propane streams. Considering the operational conditions, the mentioned method used in second and third phases, will control the dew point at −23° c at the best condition. This temperature is not proper for dew point and shows very high amount of hydrocarbons in product gas. In this study, a new process has been introduced in order to drop the gas liquid dew point (natural gas liquid) to −85° c by self-refrigeration technology. Due to the advanced nature of absorption process, the problem of methane existence in the product of gas liquids is noticeably overcome. In this process, natural gas enters the turbo expander after passing through a refrigeration cycle at −37° c and it is then expanded in an isotropic process to 2896 kPa pressure. Expander outlet with reflux and condensate produced from a cold separator are fed to an absorption tower with a reboiler and the separation will occur. The advantage of this method is controlling the concentration of methane in the product streams. Simulation results show that the process can daily produce 22,280 barrels of gas liquids with a concentration of 0.5 mole% of methane. In addition, the recovery efficiencies of propane and butane in the newly proposed method are 97.3% and 99.99%, respectively, which show a remarkable advantage over the current trend. [ABSTRACT FROM AUTHOR]

Using cell‐based engineered skin is an emerging strategy for treating difficult‐to‐heal wounds. To date, much endeavor has been devoted to the fabrication of appropriate scaffolds with suitable biomechanical properties to support cell viability and growth in the microenvironment of a wound. The aim of this research was to assess the impact of adipose tissue‐derived mesenchymal stem cells (AD‐MSCs) and keratinocytes on gelatin/chitosan/β‐glycerol phosphate (GCGP) nanoscaffold in full‐thickness excisional skin wound healing of rats. For this purpose, AD‐MSCs and keratinocytes were isolated from rats and GCGP nanoscaffolds were electrospun. Through an in vivo study, the percentage of wound closure was assessed on days 7, 14, and 21 after wound induction. Samples were taken from the wound sites in order to evaluate the density of collagen fibers and vessels at 7 and 14 days. Moreover, sampling was done on days 7 and 14 from wound sites to assess the density of collagen fibers and vessels. The wound closure rate was significantly increased in the keratinocytes‐AD‐MSCs‐scaffold (KMS) group compared with other groups. The expressions of vascular endothelial growth factor, collagen type 1, and CD34 were also significantly higher in the KMS group compared with the other groups. These results suggest that the combination of AD‐MSCs and keratinocytes seeded onto GCGP nanoscaffold provides a promising treatment for wound healing. [ABSTRACT FROM AUTHOR]

Process optimization of CO2 removal from natural gas by a polyvinylidene fluoride hollow-fiber membrane contactor is a major goal of many computational fluid dynamics (CFD) simulations in this area. In this study, a 2D CFD model based on mass transfer equation inside the tube, the membrane, and the shell section of a HMFC at steady state and laminar conditions is developed and solved by COMSOL Multiphysics with finite element approach. Simulation results show an excellent agreement with experimental data. The model predicts that higher liquid velocity and membrane porosity results in higher CO2 removal, because of enhancement of effective diffusion coefficient. Also, taller fiber length results in higher contact area and higher mass transfer of CO2 from natural gas into distilled water. Although higher temperature will decrease the CO2 removal. [ABSTRACT FROM AUTHOR]

Scaffold-based tissue engineering is considered as a promising approach in the regenerative medicine. Graft instability of collagen, by causing poor mechanical properties and rapid degradation, and their hard handling remains major challenges to be addressed. In this research, a composite structured nano-/microfibrous scaffold, made from a mixture of chitosan-β-glycerol phosphate-gelatin (chitosan- GP-gelatin) using a standard electrospinning setup was developed. Gelatin-acid acetic and chitosan β-glycerol phosphate-HCL solutions were prepared at ratios of 30/70, 50/50, 70/30 (w/w) and their mechanical and biological properties were engineered. Furthermore, the pore structure of the fabricated nanofibrous scaffolds was investigated and predicted using a theoretical model. Higher gelatin concentrations in the polymer blend resulted in significant increase in mean pore size and its distribution. Interaction between the scaffold and the contained cells was also monitored and compared in the test and control groups. Scaffolds with higher chitosan concentrations showed higher rate of cell attachment with better proliferation property, compared with gelatin-only scaffolds. The fabricated scaffolds, unlike many other natural polymers, also exhibit non-toxic and biodegradable properties in the grafted tissues. In conclusion, the data clearly showed that the fabricated biomaterial is a biologically compatible scaffold with potential to serve as a proper platform for retaining the cultured cells for further application in cell-based tissue engineering, especially in wound healing practices. These results suggested the potential of using mesoporous composite chitosan- GP-gelatin fibrous scaffolds for engineering threedimensional tissues with different inherent cell characteristics. [ABSTRACT FROM AUTHOR]