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Fibrinogen-modified gold nanoparticles (Fib-AuNPs) and 3,3′,5,5′-tetramethylbenzidine (TMB) substrate besides hydrogen peroxide (H2O2) were applied for assessment of the biomarker thrombin. Fib-AuNPs have catalytic active sites for the oxidation of TMB besides H2O2 and cause the color change of the substrate. Moreover, they can lead to the enhancement in the absorption wavelengths of 650 and 370 nm. By the addition of thrombin to Fib-AuNPs, fibrinogen turns into fibrin, and AuNPs are surrounded by fibrin. Therefore, their active catalytic sites for the oxidation of TMB besides H2O2 are covered by fibrin and cannot cause color change and absorption increase as before. The relationship between the average variations of the color intensity and changes in the absorption wavelengths at 650 and 350 nm with different concentrations of bovine thrombin added to Fib-AuNPs was studied. In such manner, three sensitive colorimetric approaches have been developed for the identification of bovine thrombin with the linear range of 20–120 pM and the limit of detection (LOD) of 17.54 pM for the average color intensity (G + B), the linear range of 20–120 pM and the LOD of 13.41 pM for the absorption peak at 650 nm, and the linear range of 40–140 pM with the LOD of 18.85 pM for absorption peak at 370 nm. The practical application of this biosensing platform was indicated through the successful determination of bovine thrombin in bovine serum. The satisfactory RSD (< 10%) and recovery values (99.11–107.61%) confirmed the feasibility of the fabricated sensor. [ABSTRACT FROM AUTHOR]

In this paper, a stochastic transmission expansion planning (TEP) in the presence of wind farms under uncertain load and wind source conditions when reliability and N-1 contingency is taken into consideration is proposed. The main aim of the suggested TEP is to minimize the total planning cost while satisfying techno-economic constraints. In this paper, reliability cost is also incorporated as the loss of load cost (LOLC) into the objective function in addition to the investment cost. In order to provide more accurate and real results, the N-1 contingency is also considered as a constraint in the TEP problem. Uncertainties for the wind source and loads in the TEP problem are modeled using a scenario-based approach and Monte Carlo simulation. Grey wolf optimization (GWO) is applied to solve the TEP problem, and it is compared to other optimization techniques. The simulation results are provided in various scenarios to confirm the efficiency of the suggested stochastic TEP. [ABSTRACT FROM AUTHOR]

Industry 4.0 recommends a paradigm shift from traditional manufacturing to automated industrial practices, especially in different parts of supply chain management. Besides, the Sustainable Development Goal (SDG) 12 underscores the urgency of ensuring a sustainable supply chain with novel technologies including Artificial Intelligence to decrease food loss, which has the potential of mitigating food waste. These new technologies can increase productivity, especially in perishable products of the supply chain by reducing expenses, increasing the accuracy of operations, accelerating processes, and decreasing the carbon footprint of food. Artificial intelligence techniques such as deep learning can be utilized in various sections of meat supply chain management––where highly perishable products like spoiled meat need to be separated from wholesome ones to prevent cross-contamination with food-borne pathogens. Therefore, to automate this process and prevent meat spoilage and/or improve meat shelf life which is crucial to consumer meat preferences and sustainable consumption, a classification model was trained by the DCNN and PSO algorithms with 100% accuracy, which discerns wholesome meat from spoiled ones. [ABSTRACT FROM AUTHOR]

• Prenatal stress induced neurobehavioural abnormalities in both dams and offspring. • Prenatal stress altered HPA function and biological factors in dams or offspring. • Perinatal FLX dose dependently decreased anxiety and depression in stressed dams. • Perinatal FLX dose dependently altered behavioural disorders in stressed offspring. • Perinatal FLX dose dependently affected biological factors in stressed offspring. Both untreated and SSRI antidepressant treated maternal depression during the perinatal period can pose both short-and long-term health risks to the offspring. Therefore, it is essential to have an effective SSRI treatment consisting of the lowest effective dose beneficial to the mother, without causing adverse effects on offspring development. The effects of prenatal stress on neurobehavioral outcomes were studied in the pregnant and lactating rat dam, and her offspring. Furthermore, stressed dams were treated with different doses of fluoxetine (FLX; 5, 10and 25 mg/kg) during pregnancy and the postpartum period. We found that prenatal stress-induced anxiety-and depressive-like behaviour and increased HPA-axis function in pregnant and postpartum dams, and in offspring. Maternal stress impaired object recognition but did not affect spatial memory in offspring. Prenatal stress decreased whole-brain serotonin and brain-derived-neurotrophic-factor, and increased interleukin-17 and malondialdehyde, but did not affect oxytocin and interleukin-6 in the brains of offspring. Maternal treatment with 5 mg/kg FLX during the perinatal period did not rescue any stress-induced anxiety/depressive-like behaviour in the pregnant and postpartum dam and had only a few rescuing effects in offspring. Maternal FLX treatment with 10 mg/kg did rescue most stress-induced anxiety-and depressive-like behaviour or HPA-axis-function in dams and offspring. The highest dose tested, 25 mg/kg FLX, had the rescuing properties in dams while having the same, or an even greater, detrimental effect as prenatal stress on offspring behaviour and molecular alterations in the brain. Our results show prenatal stress rescuing properties for FLX treatment in the pregnant and postpartum dam, with dose-dependent effects on the offspring. [ABSTRACT FROM AUTHOR]

• Bicuculline was used for the neonatal blockade of GABA-A receptors. • Treatment with the highest dose of bicuculline increases memory in adulthood. • Administration of a low dose of bicuculline impairs memory in adulthood. • Bicuculline treatment increases the hippocampal and prefrontal cortex BDNF levels. • Neonatal treatment with bicuculline alters the behavior of the adult male rats. Gamma-aminobutyric acid (GABA) is an important inhibitory neurotransmitter in the mature brain. At an early developmental period, it acts in an excitatory manner that influences many processes of proliferation, migration, and differentiation of the neurons. Previous evidence indicated that manipulation of the GABAergic system function by activation or blockade of its receptors during developmental periods leads to behavioral and cognitive abnormality in adulthood. Therefore, we examined the effects of neonatal blockade of GABA-A receptors by bicuculline on behavior, cognitive function, and hippocampal and prefrontal cortex (PFC) brain-derived neurotrophic factors level (BDNF) in adulthood. As a result, neonatal rats were treated with either bicuculline (75,150, and 300 μg/kg) or DMSO on postnatal days 7,9, and 11. These groups underwent the behavioral (open field, elevated plus maze, and hot plate) and learning and memory (passive avoidance learning and memory) tests in postnatal days (PNDs) 61−70. After the ending of the behavioral tests, the rats were sacrificed under deep anesthesia and the hippocampi and prefrontal cortex (PFC) of the brain were removed for assessing the BDNF mRNA expression. Our results indicated that neonatal administration of bicuculline at the highest dose increased passive avoidance memory and hippocampal BDNF level. Meanwhile, this drug at a low dose impaired this type of memory and increased PFC BDNF level. Besides, treatment with bicuculline during postnatal days increased anxiety and pain sensitivity in a dose-dependent manner. Taken together, these findings confirmed the notion that GABA-A receptors during the developmental period are important for programming neurobehavioral phenotypes in adult life. [ABSTRACT FROM AUTHOR]

Why layers II/III of entorhinal cortex (EC) deteriorate in advance of other regions during the earliest stages of Alzheimer's disease is poorly understood. Failure of retrograde trophic support from synapses to cell bodies is a common cause of neuronal atrophy, and we accordingly tested for early-life deterioration in projections of rodent layer II EC neurons. Using electrophysiology and quantitative imaging, changes in EC terminals during young adulthood were evaluated in male rats and mice. Field excitatory postsynaptic potentials, input/output curves, and frequency following capacity by lateral perforant path (LPP) projections from lateral EC to dentate gyrus were unchanged from 3 to 8-10 months of age. In contrast, the unusual presynaptic form of long-term potentiation (LTP) expressed by the LPP was profoundly impaired by 8 months in rats and mice. This impairment was accompanied by a reduction in the spine to terminal endocannabinoid signaling needed for LPP-LTP induction and was offset by an agent that enhances signaling. There was a pronounced age-related increase in synaptophysin within LPP terminals, an effect suggestive of incipient pathology. Relatedly, presynaptic levels of TrkB--receptors mediating retrograde trophic signaling--were reduced in the LPP terminal field. LTP and TrkB content were also reduced in the medial perforant path of 8- to 10-month-old rats. As predicted, performance on an LPP-dependent episodic memory task declined by late adulthood. We propose that memory-related synaptic plasticity in EC projections is unusually sensitive to aging, which predisposes EC neurons to pathogenesis later in life. [ABSTRACT FROM AUTHOR]

CD8+ T cells are critical mediators of adaptive immunity, and enhancing their function can promote robust responses against invading pathogens and neoplastic cells. In addition to TCR stimulation, the provision of costimulation through ligation of TNFR family members, such as OX40 (CD134), provides essential signals driving T cell differentiation, survival, and memory in part through enhanced IL-2/IL-2R signaling. Interestingly, TCR stimulation in the presence of IL-2 upregulates intracellular expression of the b-galactoside binding protein, Galectin-3 (Gal-3). Gal-3 has been shown to regulate Th1/Th2 polarization of CD4+ T cells; however, the extent to which Gal-3 regulates the OX40/IL-2 signaling axis and CD8+ T cell proliferation, effector function, and/or survival is unknown. In this study, we demonstrate that murine Gal-3-deficient CD8+ T cells exhibited no defects in early (36 h) activation or proliferation following TCR stimulation. In contrast, Gal-32/2 CD8+ T cells exhibited decreased survival and a reduced capacity to develop into memory cells following stimulation with cognate Ag plus agonist anti-OX40 mAb or IL-2 in vivo. Decreased survival of Gal-3-/-T cells was associated with increased apoptosis and occurred in a cell-intrinsic manner. Together, these data implicate intracellular Gal-3 as a critical mediator of OX40-mediated CD8+ T cell survival and memory formation following Ag exposure. [ABSTRACT FROM AUTHOR]

A multi-functionalized Na-Y/ZnO/NH2/SH composite adsorbent was synthesized for Pb2+ and Ni2+ removal from single and binary aqueous systems. The prepared composites were characterized by FTIR, FESEM, XRD, BET, and N2 adsorption–desorption techniques. The effect of ZnO nanoparticles, amine, and thiol functional groups on the adsorption performance was studied in a batch system. The adsorption behavior of Pb2+ and Ni2+ ions was evaluated as a function of initial metal concentration, contact time, pH, and temperature. The adsorption process of both Pb2+ and Ni2+ ions followed the double-exponential kinetics model. Also, the investigation of isotherm models exhibited a monolayer adsorption onto the synthesized composite. The maximum adsorption capacity of Na-Y/ZnO/NH2/SH composite was found to be 177.9 mg/g for Ni2+ ions and 295.4 mg/g for Pb2+ ions. The synthesized Na-Y/ZnO/NH2/SH composite was regenerated multiple times showing a promising adsorbent with high regeneration efficiency. In a binary system, the inhibitory influence of Pb2+ ions on the Ni2+ adsorption was greater than the inhibitory influence of Ni2+ ions on the Pb2+ adsorption. [ABSTRACT FROM AUTHOR]

Approaching the critical region of hydrocarbon + water mixtures will lead to an unusual increment in miscibility. In this research, CPA EoS is satisfactorily applied to predict the properties of three hydrocarbon + water mixtures at near/supercritical temperatures. First, CPA EoS is applied to evaluate the density of pure water and hydrocarbons in a range of pressure at various temperatures. To make a comparison on CPA models, both SRK and PR are accounted in the physical term of the model. In the case of pure hydrocarbons, the effect of volume shift correction (VS) on modeling results is also investigated. Afterwards, CPA EoS is used to predict the density of mixtures and relative volume change of mixing for hydrocarbon rich phase of mixtures at various temperatures. The results revealed that CPA EoS would be a reliable choice to predict complex behavior of hydrocarbon + water mixtures in a wide range of pressures and temperatures. • SRK/PR-CPA are applied to estimate excess volume of water + hydrocarbon mixtures at high temperatures near critical region. • Impacts of pressure and temperature change, and volume shift on density and excess volume of mixtures are investigated. • The CPA models can predict densities of these complex mixtures with/without tuning the adjusting parameters. [ABSTRACT FROM AUTHOR]

In this research, an experimental evaluation is conducted on the hydrothermal behavior of water-based manganese ferrite nanofluid flowing in a metal foam tube. For this purpose, manganese ferrite nanoparticles are synthesized, and X-ray diffraction and scanning electron microscopy are implemented to specify the samples for determination of phase and size of nanoparticles. The effects of Reynolds number, Prandtl number, and presence of MnFe2O4 nanoparticles inside the water on the Nusselt number and friction factor have been studied. The experimental analysis shows that the increment of Reynolds number, Prandtl number, and nanoparticles concentration improve the heat transfer performance. The maximum of 19.1% and 10.5% increase in Nusselt number and friction factor have been achieved respectively by dispersion of 2 wt% manganese ferrite nanoparticles inside the deionized water at Reynolds number of 1,000. A hydrothermal index is proposed to consider the thermal and hydrodynamic characteristics of the nanofluid, and it is attained that the convection heat transfer improvement dominates the pressure drop in this work. According to the experimental results, the Nusselt number and friction factor of the nanofluid is modeled as a function of Reynolds number, Prandtl number, and nanoparticles concentration using artificial neural network with an acceptable precision. [ABSTRACT FROM AUTHOR]

Abstract Many patients with sporadic Alzheimer's disease (AD) suffer from memory impairment, anxiety- and depression. The systemic utility of N-Methyl- d -Aspartate (NMDA) receptor antagonists has been shown to be potential therapeutic target for memory loss in AD. However, there is no evidence that shows whether NMDA receptor antagonists have the same effects when these blockers are directly used within the brain regions including hippocampus. It might be an urgent to further explore the therapeutic role of NMDA receptor antagonists in behavioral abnormalities such as anxiety and depression in AD. The aim of this study was to determine whether blockade of the hippocampal NMDA receptors could attenuate neurobehavioral abnormalities in rats with sporadic AD. Twelve days after AD induction by streptozotocin (STZ), animals received either vehicle or MK-801 (NMDA receptor antagonist) in the hippocampus for 10 days. Two or five days after the last MK-801 treatment, spatial memory, anxiety- and depression-related behaviors, and inflammatory cytokines (interleukin-(IL)-6, IL-1β and tumor necrosis factor (TNF)-α) were evaluated. Our findings indicated that STZ treatment significantly elevated hippocampal inflammation, impaired spatial memory, and increased anxiety- and depression-related symptoms in rats. Interestingly, the hippocampal NMDA receptor blockade improved these neurobehavioral phenotypes and decreased inflammatory cytokines in the hippocampus of STZ-treated rats. Hippocampal NMDA receptors might be involved in neurobehavioral abnormalities via inflammation in sporadic AD. Highlights • Sporadic Alzheimer-like disease was induced by ICV injection of streptozocin (STZ). • Hippocampal NMDA receptor blockade improved memory in STZ-treated rats. • Hippocampal NMDA receptor blockade decreased anxiety behavior in STZ-treated rats. • Hippocampal NMDA receptor blockade reduced depression symptoms in STZ-treated rats. • NMDA receptor blockade reduced hippocampal inflammation in STZ-treated rats. [ABSTRACT FROM AUTHOR]

Rationale: Considerable clinical and experimental studies have shown that depression-related disorders are the most common neuropsychiatric symptoms in Alzheimer's disease (AD), affecting as many as 20–40% of patients. An increasing amount of evidence shows that monoamine-based antidepressant treatments are not completely effective for depression treatment in patients with dementia. Minocycline, a second-generation tetracycline antibiotic, has been gaining research and clinical attention for the treatment of different neuropsychiatric disorders, and more recently depression symptom in humans. Methods: In the present study, we investigated the effects of Aβ1–42 administration alone or in combination with minocycline treatment on depression-like behaviors and anti/pro-inflammatory cytokines such as interleukin(IL)-10, IL-β, and tumor necrosis factor (TNF)-α in the hippocampus of rats. Results: Our results showed that Aβ1–42 administration increased depression-related behaviors in sucrose preference test, tail suspension test, novelty-suppressed feeding test, and forced swim test. We also found significant increases in IL-1β and TNF-α levels in the hippocampus of Aβ1–42-treated rats. Interestingly, minocycline treatment significantly reversed depression-related behaviors and the levels of hippocampal cytokines in Aβ1–42-treated rats. Conclusion: These findings support the idea that there is a significant relationship among AD, depression-related symptoms, and pro-inflammatory cytokines in the brain, and suggest that antidepressant-like impacts of minocycline could be due to its anti-inflammatory properties. This drug could be of potential interest for the treatment of depression in patients with Alzheimer's disease. [ABSTRACT FROM AUTHOR]

Abstract Asphaltene deposition in surface facilities, wellbore and near wellbore region poses a chronic problem during oil production processes. It reduces permeability significantly by blocking pore throats as well as wettability alteration toward oil-wet. In this study, near wellbore damage due to asphaltene deposition is addressed. A numerical approach has been followed to investigate the impacts of asphaltene deposition in near wellbore region using an Iranian crude oil sample. An IMPEC (Implicit Pressure and Explicit Compositions) compositional simulator has been developed in cylindrical coordinates. Three mechanisms of asphaltene damage including porosity reduction, permeability reduction and wettability alteration are taken into account, and the impact of each mechanism is individually discerned. It is assumed precipitated asphaltene is a pure dense liquid and it is determined by LLE calculation using PR-EoS. The reduction in permeability is correlated with porosity reduction using a power law relation. To model wettability alteration, instantaneous wettability dependent properties (relative permeability, capillary pressure and residual saturations) are determined by a weight averaging between before/after deposition state. By assuming porous media is a bundle of capillary tubes, a weight factor is suggested which is sensitive to asphaltene particle size and their orientation on the surface and calculated dynamically during the simulation. Furthermore, sensitivity analysis is done to investigate the effect of model parameters. It is found that the wettability alteration is the main cause for the reduced production rate. Wettability alteration could reduce oil production even up to several times more than porosity and permeability reduction. The results also reveal that at early time of production, most deposition occurs in the vicinity of the well but as time elapses, the maximum deposition point expands gradually to farther areas from the wellbore. Highlights • An IMPEC compositional simulator in cylindrical coordinates is used to investigate asphaltene issue in near wellbore region. • Porosity reduction, permeability reduction and wettability alteration are taken into account. • The reduction in permeability is correlated with porosity reduction using a power law relation. • Wettability dependent properties are determined by a weight averaging between before/after deposition state. [ABSTRACT FROM AUTHOR]

This paper assesses the contribution of TiO2 nanoparticles on thermal performance of a 0.5 mass% aqueous solution of carboxymethyl cellulose (CMC) in a square channel. In this regard, a neural network model is firstly developed for modeling of power law index, consistency index, and thermal conductivity of the aqueous solution of TiO2/CMC-water non-Newtonian nanofluid in terms of the nanoparticle concentration and temperature. Then, an attempt is made to evaluate the friction factor and heat transfer coefficient relative values. According to the results, it is found that the friction factor ratio is directly proportional to the temperature and nanoparticle content, while it inversely varies relative to the shear rate. Moreover, heat transfer coefficient ratio is improved at elevated nanoparticle content, and this improvement is much more profound at higher temperature conditions. For practical purposes, the nanofluid hydrothermal performance index is examined since the addition of nanoparticles increases both heat transfer and friction factor. The corresponding data disclose that the performance index is directly proportional to the nanoparticle content, especially at decreased shear rate and elevated temperature conditions. The application of TiO2/CMC-water nanofluid is found to be more favorable for applications with elevated shear rate conditions. [ABSTRACT FROM AUTHOR]

Recently, the use of nanoparticles in extraction columns has gained increasing attention due to their potential to enhance mass transfer processes. Most of the reported work, however, has been concerned with mass transfer enhancement in gas–liquid systems in the presence of nanoparticles, while limited studies of liquid–liquid systems have been reported. Liquid–liquid extraction is an extensively employed separation method that has taken on a substantial role in engineering and industrial applications for recovery processes. Therefore, the aim of this review article is to provide an overview of the state-of-the-art from the available literature on the effect of nanoparticles on the hydrodynamic behavior and mass transfer performance of liquid–liquid systems. Attention is also given to providing an understanding of the mechanisms responsible for the improvements in mass transfer with the use of nanoparticles. In the majority of studies, the presence of nanoparticles was found to be beneficial and to lead to improved mass transfer, although a few investigations reported a detrimental impact of nanoparticles. The literature does not clearly describe the conditions under which the addition of nanoparticles would be unfavorable. Moreover, the addition of nanoparticles always introduces potential drawbacks, such as sedimentation, accumulation, or clogging inside extraction columns, as well as the need to separate the nanoparticles at the outlets. These drawbacks have not been considered in the literature, limiting the practical employment of nanoparticles in this industry. [ABSTRACT FROM AUTHOR]

In this research, an experimental study is conducted on the hydrothermal characteristics of Fe 3 O 4 /water ferrofluid flow through a metal foam tube under constant and alternating low-frequency magnetic field. The Nusselt number and friction factor of Fe 3 O 4 /water ferrofluids are measured and presented at different nanoparticle concentrations, Reynolds numbers, magnetic field intensities as well as frequencies. The results have shown that when the magnetic field intensity and frequency increase, there will be an enhancement in the Nusselt number. A maximum of 36.2% improvement in the Nusselt number of ferrofluid is obtained at Re  = 200, for 2% nanoparticle weight fraction under alternating magnetic field with 20 Hz frequency. Also, the friction factor of Fe 3 O 4 /water ferrofluid is observed to be higher than that of DI-water. Moreover, the effect of alternating low-frequency magnetic field is found to be insignificant on the friction factor at the constant magnetic field. The thermal performance index of 1.26 is achieved by applying alternating magnetic field intensity of 400 G with 20 Hz frequency at Re  = 1000 for the ferrofluid with 2% weight fraction. Finally, a polynomial neural network based on the group method of data handling (GMDH) is established to predict the Nusselt number and friction factor in this study. It is obtained that GMDH-type neural network provides a useful model which can precisely estimate those parameters. [ABSTRACT FROM AUTHOR]

Background: Vitamin D is one of fat-soluble vitamins. It has of great importance in increasing intestinal absorption of calcium, magnesium, phosphate, and zinc. Sun is the main source for this vitamin and there are few foods that contain it, for example milk and egg. From a long standing, vitamin D deficiency has been a health problem in the world. Vitamin D has great importance in the growth of bone, so the deficiency of it or imbalance of its metabolism inside the body leads to major problems, most notably of them is rickets among children. Objectives: This is a cross-sectional study, aiming to study the awareness of public regarding vitamin D deficiency among children and to reveal the role of primary health care in raising people's awareness of vitamin D deficiency. Materials and methods: Electronic questionnaires are used to collect data. They contain personal sociodemographic characteristics, information about vitamin D deficiency and the role of primary health care in raising people's awareness of vitamin D deficiency. The study recruits 500 participants; medical field workers were not included in the study. Data were analyzed using SSPS version 22. Results: It was observed that 89% of the total sample size has knowledge on vitamin D where 94.3% of mothers heard about vitamin D, 68% knew that vitamin D is important, and 72.11% believed that vitamin D is manufactured in the body. More than two thirds (69.83%) said that the ultraviolet sun-rays is the main source of vitamin D and 68.88% of parents declared that they had attend a lecture given by a physician in in the primary health care center on the importance of vitamin D where, fathers (40.2%) were more than mothers (26.6%) in getting their information. Conclusion: More research is needed to assess the level of community awareness as it is the best solution to reduce or eliminate the problem. Health education campaigns about vitamin D and its importance with more intensification in Men places as they had a low awareness. Training of primary health care physicians and their supervision for raising awareness of their community. [ABSTRACT FROM AUTHOR]

In order to avoid the costs of experimental evaluations, soft computing methods like artificial neural network (ANN) and genetic algorithm have remarkably grabbed the attentions of investigators for predicting the hydrothermal characteristics of different types of nanofluids. In this paper, the implementation of ANN and genetic algorithm for modeling and multi-criteria optimizing the hydrothermal behavior of SiO 2 /water nanofluid has been investigated. Using the data obtained from the experimental analysis, an ANN model is developed to estimate the pressure drop and Nusselt number as a function of volume concentration, Reynolds number, and inlet temperature. Different network structures were assessed and it has been achieved that a network with 2 hidden layers and 6 neurons in every layer provides the most accurate prediction. It is revealed that the developed network is satisfactorily accurate to determine the Nusselt number and pressure drop of SiO 2 /water nanofluid compared to the empirical correlations. To optimize the hydrothermal behavior of the nanofluid (i.e. to find the optimal cases with highest Nusselt number and the relatively least pressure drop), the genetic algorithm coupled with compromise programming approach has been implemented considering decision maker's attitude. [ABSTRACT FROM AUTHOR]

Evaluation of phase behavior of mixtures containing reservoir fluids and associating (hydrogen-bonding) compounds like water is an important task in oil production and refining processes. In current work, a CPA computational approach was adopted to predict water solubility in pure hydrocarbons, petroleum fractions and heavy reservoir fluids. The reservoir fluid was considered as a single pseudo-component to simplify the model. The solvation (cross-association) between water and hydrocarbon molecules was taken into account while the self-association between hydrocarbon molecules was ignored. All the binary interaction coefficients were considered zero. Cross-association volume parameters of various mixtures were tuned to fit the experimental trend for each hydrocarbon and reservoir fluid as the only adjusting parameter of the model. The CPA model was applied to a number of pure hydrocarbons, petroleum fractions and heavy crudes with molecular weights more than 78 kg/kmol in a range of elevated temperatures suitable for thermal recovery processes. A generalized correlation is proposed to estimate the cross-association volume parameter of different hydrocarbon + water mixtures in terms of hydrocarbons molecular weight and Watson characterization factor. The suggested model is benchmarked against three complex water solubility data sets for Athabasca bitumen from the literature. The results are promising to extend the CPA model to hydrocarbons and reservoir fluids with a reasonable accuracy in the temperature range from 279 up to 644 K. [ABSTRACT FROM AUTHOR]

The costly and time-consuming determination of thermophysical properties of nanofluids through the experimental analysis leads the current investigations to use the soft computing methods like correlating, artificial neural network (ANN) and genetic algorithm. In this study, the application of ANN, empirical correlations and genetic algorithm for modeling and multi-criteria optimization of the thermophysical properties of clove-treated MWCNTs nanofluid which has been synthesized through a facile and eco-friendly procedure has been investigated. In this contribution, totally 6 structures are assessed: networks including one and two hidden layers with 2, 4, and 6 neurons. From assessment of the ANN, it is found that the network including two hidden layers with 4 neurons in every layer results in the least difference between the network outputs and the experimental data, providing the best performance. It is concluded that the optimal ANN model is a more precise and accurate way to predict the thermal conductivity and viscosity of environmentally friendly C-MWCNT/water nanofluid compared to empirical correlations obtained from non-linear regression method. Moreover, the evolutionary algorithm has been implemented for achieving the optimal conditions to maximize the thermal conductivity and to minimize the viscosity of nanofluid. In this regard, based on real-world engineering experience, the final optimal solutions opted from several distinguished procedures of decision-making including the Bellman-Zadeh, TOPSIS and LINMAP approaches has been investigated in parallel. The results of this study revealed that the obtained outputs using TOPSIS and LINMAP procedures are the closest to ideal solution. [ABSTRACT FROM AUTHOR]

This study presents the application of a modified single-phase method by thermal dispersion model incorporating heterogeneous distribution of nanoparticle concentration for evaluating thermal performance of a nanofluid in a circular porous metal foam tube. Numerical approach was conducted for Re = 200–1000, mean concentration of 0.5–2%, and metal foam porosity of 0.7–0.9. It is observed that the predicted data by application of the thermal dispersion approach are in satisfactory agreement with those obtained experimentally, whereas applying the general homogeneous model results in an underestimation. The results reveal that the heterogeneity of the concentration distribution is directly proportional to nanoparticle mean concentration, Reynolds number, and the metal foam porosity. The velocity and temperature profiles at a cross section have been found to be flatter in dispersion model compared to those obtained from the homogeneous model. Furthermore, it is achieved that the Nusselt number varies directly relative to mean concentration and Reynolds number, whereas it inversely alters relative to the porosity. This reduction is found to be more profound at lower porosities. [ABSTRACT FROM AUTHOR]

In this work, a two-phase mixture model for evaluation of flow and heat transfer performance of SiO 2 /water nanofluids under turbulent flow was proposed by considering the heterogeneity of concentration due to crossed effect and the influences of shear rate, viscosity gradient, thermophoresis and Brownian motion on the diffusion of the nanoparticles. The effects of Peclet number, Reynolds number, nanoparticle size and nanofluid mean concentration on the distribution of nanoparticles have been evaluated. The values of thermal conductivity and viscosity as the main thermophysical properties of nanofluids changed across different layers of the liquid due to the heterogeneous distribution of concentration. It was observed that an increase in the Peclet number caused heterogeneity in the distribution of the properties. The achieved nanoparticle distribution has been implemented for analysis of nanofluid using two-phase mixture model. It was found that the effect of nanofluid concentration on the Nusselt number was more noticeable in lower Reynolds numbers due to the insignificant effect of flow momentum on heat transfer. The maximum of 43.9% enhancement in convection heat transfer was achieved by dispersion of 4% SiO 2 nanoparticles inside DI-water at Re = 25,000. [ABSTRACT FROM AUTHOR]

The utilization of phase change materials (PCMs) in buildings leads to the reduction of energy consumption and maintaining the indoor temperature within the comfort range. The PCM performance strongly depends on the climatic conditions, causing a major challenge. To overcome this issue, the employment of a double-layer PCM system is introduced. The energy and economic assessments of various double PCM systems in the building located in different climatic conditions of Iran have been conducted for the first time. In this study, two PCM wallboards with different enthalpy and melting temperatures were embedded in the external walls of a residential building located in various climatic regions of Iran. The performance of the double-layer PCM system in five cities of Iran including Tehran, Isfahan, Shiraz, Tabriz, and Bandar Abbas during hot and cold months of the year was evaluated from energy and economic viewpoints. It was inferred that embedding a double-layer PCM system reduces the heating/cooling energy consumption compared to single-layer ones. It was concluded that the RT18/RT28 double PCM system was the best candidate to be employed in the external walls of the building located in Tehran and Shiraz, which reduced the total energy consumption of the building up to 6.26% and 5.17%. The RT18/RT22 double PCM system was the most efficient system for the building placed in Tabriz and Isfahan reducing the total energy consumption up to 4.41% and 3.87%, and the RT22/RT28 double PCM system had the best performance in the building located in Bandar Abbas, which could save 6.58% of total energy. Moreover, it was concluded that the use of a double PCM system reduced temperature fluctuations in the external walls. In addition, the economic analysis was performed using the dynamic payback period and the results revealed that the employment of a double-layer PCM system reduced the investment return period by up to 50%. [ABSTRACT FROM AUTHOR]

Recently, it has been observed that the use of magnetic nanoparticles and the magnetic field would result in heat and mass transfer intensification. But most of the investigations have been devoted to the enhancement of heat transfer. However, the investigations on the applicability of magnetic nanoparticles for mass transfer improvement are still in the developing stage. In the present study, the effect of MnFe 2 O 4 nanoparticles on the mass transfer performance of a packed extraction column is evaluated in the presence of constant and alternating magnetic fields. The column is filled with Penta-Pak TM PS-500M1 structured packing; while four identical bar electromagnets made from zinc ferrite cores are used to generate the quadrupole magnetic field. The (toluene-acetic acid)-water system is employed. Spinel-type manganese ferrite nanoparticles are added to the organic dispersed phase (toluene + acetic acid) to intensify solute transfer. The quadrupole magnetic field is applied from 100 to 500 G intensity and 100 to 500 Hz frequency, accompanied with different nanoparticle concentrations from 0.001 wt% to 0.005 wt%. According to our observations, mass transfer performance increases remarkably in the presence of magnetic nanoparticles under the influence of magnetic field. Compared with no magnetic field, maximum improvements of 115% and 43% in overall mass transfer coefficient and extraction fraction are observed under alternating magnetic field with 300 Hz frequency and 500 G intensity for 0.003 wt% nanoparticle concentration. That is, by using the magnetic nanoparticles and the magnetic field, one can considerably improve the performance of a liquid-liquid extraction system. [ABSTRACT FROM AUTHOR]

In the present experimental study, the influence of permanent and alternating magnetic fields on the flow and thermal behavior of MnFe 2 O 4 magnetic nanofluid flowing through a circular open-cell metal foam tube is investigated under homogeneous heat flux conditions. The experiments are performed at various nanoparticle concentrations, Reynolds numbers and magnetic fields with different strengths and frequencies. According to the observations, the heat transfer rate enhances directly relative to nanoparticle concentration and Reynolds number in attendance of magnetic field, whereas its maximum value of 16.4% is found for 2 wt% nanoparticles at Re = 200 under alternating field with 400 G strength and 20 Hz frequency. Moreover, it is observed that the influence of strength and frequency of magnetic field is insignificant for the pressure drop. Hydrothermal efficiency as the ratio of the Nusselt number to the ratio of the pressure drop is defined in order to evaluate the privilege of using MnFe 2 O 4 nanofluids in practical applications. The maximum efficiency of 1.25 is observed at 2 wt% under magnetic field with 400 G and 20 Hz at Re = 1000. [ABSTRACT FROM AUTHOR]

This article concerns the influence of different ZnO nanoparticle concentrations (0.001, 0.003, 0.005 and 0.01 wt%) along with operating parameters (i.e., pulsation intensity and flow rate of dispersed and continuous phases) and physical properties on mean drop size and drop size distribution in a horizontal pulsed perforated-plate extraction column for the toluene–acetone–water and butyl acetate–acetone–water systems (mass transfer direction from the dispersed phase to the continuous phase). According to the results, it is observed that the addition of nanoparticles has a remarkable influence on breakage and coalescence of drops and consequently their size distribution. Accordingly, adding nanoparticles reduces the interfacial tension due to internal turbulence caused by nanoparticles’ Brownian motion inside each drop. It is found that drop size distribution will shift to the left and the density of small droplets will increase in the presence of ZnO nanoparticles in the column. Furthermore, new correlation is proposed to predict mean drop size in terms of operating parameters, physical properties and nanoparticle concentration. It is also found that the maximum entropy principle is suitable to predict drop size distribution in a horizontal extraction column. [ABSTRACT FROM AUTHOR]

In this paper, an experimental evaluation on the viscosity of water-based manganese ferrite nanofluid with and without magnetic field with 100, 200, 300, and 400 G intensities has been conducted. The Brookfield DV-I PRIME viscometer is implemented to measure the MnFe 2 O 4 /water nanofluid viscosity and to evaluate the influence of different volume concentrations (from 0.25% to 3%) and various temperatures (from 20 to 60 °C) on the viscosity. According to the measurements, viscosity incrementally increases with the augmentation of nanoparticles concentration while it remarkably decreases at higher temperatures under absence and attendance of magnetic field. The maximum viscosity ratio of 1.14 is achieved at 3 vol% of nanoparticles and 20 °C under no magnetic field, whereas it increments to maximum viscosity ratio of 1.75 at 3 vol% of nanoparticles and 40 °C under 400 G magnetic field. Furthermore, new correlation is proposed for determination of viscosity of MnFe 2 O 4 /water nanofluids in terms of magnetic field intensity, volume concentration and temperature. [ABSTRACT FROM AUTHOR]

An experimental study is conducted to investigate the convection heat transfer of Fe 3 O 4 /water nanofluid through a porous metal foam tube with uniform heat flux under the influence of constant magnetic field. This magnetic field is generated by four identical electromagnets. The electromagnets sequence is one of the most important parameters that has considerable effect on the convection heat transfer in this subject. Therefore, four different configurations of electromagnets are considered and the efficient arrangement is obtained by a numerical simulation using single-phase method in order to reach the higher heat transfer rate. Furthermore, the effects of Reynolds number, nanofluid weight fraction and magnetic field intensity on the forced convection heat transfer in the porous metal foam tube are examined under presence and absence of constant magnetic field. The experimental results show that the application of Fe 3 O 4 /water nanofluid enhances the convection heat transfer compared to DI-water. Additionally, implement of constant magnetic field leads to improve the convection heat transfer of nanofluid through the porous metal foam tube. This heat transfer improvement is more intensified in the lower fluid velocities as well as higher nanoparticle weight fractions. The maximum of 23.4% heat transfer enhancement is obtained by dispersion of 2% weight fraction of nanofluid inside the DI-water at Re = 200 under applied magnetic field of 200 G (0.02 T) intensity. A new correlation has been proposed for the Nusselt number of Fe 3 O 4 /water nanofluid in terms of Reynolds number, Prandtl number, nanoparticle weight fraction and magnetic field intensity which predicts the experimental data accurately. [ABSTRACT FROM AUTHOR]

Gamma-aminobutyric acid (GABA) plays an inhibitory role in the mature brain, and has a complex and bidirectional effect in different parts of the immature brain which affects proliferation, migration and differentiation of neurons during development. There is also increasing evidence suggesting that activation or blockade of the GABA-A receptors during early life can induce brain and behavioral abnormalities in adulthood. We investigated whether neonatal blockade of the GABA-A receptors by bicuculline can alter anxiety- and depression-like behaviors, body weight, food intake, corticosterone and testosterone levels in adult mice (postnatal days 80–95). To this end, neonatal mice were treated with either DMSO or bicuculline (70, 150 and 300 μg/kg) during postnatal days 7, 9 and 11. When grown to adulthood, mice were exposed to behavioral tests to measure anxiety- (elevated plus-maze and light-dark box) and depression-like behaviors (tail suspension test and forced swim test). Stress-induced serum corticosterone and testosterone levels, body weight and food intake were also evaluated. Neonatal bicuculline exposure at dose of 300 μg/kg decreased anxiety-like behavior, stress-induced corticosterone levels and increased testosterone levels, body weight and food intake, without significantly influencing depression-like behavior in adult male mice. However, no significant changes in these parameters were observed in adult females. These findings suggest that neonatal blockade of GABA-A receptors affects anxiety-like behavior, physiological and hormonal parameters in a sex-dependent manner in mice. Taken together, these data corroborate the concept that GABA-A receptors during early life have an important role in programming neurobehavioral phenotypes in adulthood. [ABSTRACT FROM AUTHOR]

In this work, the evaluation of thermal conductivity of MnFe 2 O 4 /water nanofluids in attendance of magnetic field is conducted. The MnFe 2 O 4 /water is synthesized and prepared in different nanoparticles concentrations, from 0.25% to 3%. The thermal conductivity of nanofluids has been determined at various nanofluid concentrations and temperatures with and without magnetic field. It is found that the thermal conductivity of nanofluid remarkably improves with augmentation of solid volume fraction. Moreover, by incrementing the nanofluid temperature, the thermal conductivity improves under no magnetic field, while it decreases at higher temperatures in attendance of magnetic field. The highest thermal conductivity improvement is achieved 26.4% at 60 °C and 3 vol.% of nanoparticles under no magnetic field and 36.5% under 400 G magnetic field which occurs at 20 °C and 3 vol.% of nanoparticles. Furthermore, an empirical correlation is derived to estimate thermal conductivity of MnFe 2 O 4 /water nanofluid in terms of magnetic field intensity, volume concentration, and temperature. [ABSTRACT FROM AUTHOR]

BACKGROUND Although Heller myotomy is one of the most effective treatments for achalasia, it may be associated with early or late symptom relapse in some patients. Therefore, additional treatment is required to achieve better control of symptoms. Aim: To evaluate the safety and efficacy of pneumatic balloon dilation (PBD) in patients with symptom relapse after Heller myotomy. METHODS Thirty six post-myotomy patients were evaluated from 1993 to 2013. Six patients were excluded from the analysis because of comorbid diseases or epiphrenic diverticula. Thirty patients were treated with PBD. Primary outcome was defined as a decrease in symptom score to 4 or less and a reduction greater than 80% from the baseline in the volume of barium in timed barium esophagogram in 6 weeks. Achalasia symptom score (ASS) was assessed at 1.5, 3, 6, and 12 months after treatment and then every six months in all patients and PBD was repeated in case of symptom relapse (ASS>4). RESULTS The mean age of the patients was 45.5±13.9 years (range: 21-73). Primary outcome was observed in 25 patients (83%). The mean ASS of the patients dropped from 7.8 before treatment to 1.3±2.0 at 1.5 months after treatment (p=0.0001). The mean volume and height of barium decreased from 43.1±33.4 and 7.1±4.7 to 6.0±17.1 and 1.1±2.2, respectively (p=0.003, p=0.003). The mean duration of follow-up was 11.8±6.3 years. At the end of the study, 21 patients (70%) reported sustained good response. No major complications such as perforation or gross bleeding were seen. CONCLUSION PBD is an effective and safe treatment option for achalasia in patients with symptom relapse after Heller myotomy. [ABSTRACT FROM AUTHOR]

Saturated water solubility values in hydrocarbon liquids span more than four orders of magnitude and are characterized by high relative error. Development of reliable correlations is particularly challenging for ill-defined and asymmetric hydrocarbon mixtures where fluid characterization and pseudo binary phase behavior type are uncertain. In this work, predictive correlations targeting this application, below the critical temperature of water, are explored and two promising models are compared with computation methods available in the literature. The model inputs include easily measurable properties (hydrogen mass fraction, fluid density at ambient conditions) as well as KWatson, mean molar mass and the average boiling point of the hydrocarbon mixture. These latter three inputs are complex and frequently difficult to define parameters encountered in refinery characterization of ill-defined organic mixtures. Models comprising one or two input variables were fit using a training data set comprising pure hydrocarbons and Athabasca bitumen. The average deviation of the models from these reference experimental data was found to be comparable to the uncertainty of the reference data in most cases. However most of the models exhibited high deviation and bias relative to the test data set comprising ill-defined hydrocarbon mixtures. Two models are shown to be robust numerically, insensitive to the uncertainty of input variables, and applicable irrespective of the pseudo binary phase behavior type with water (Type II, Type IIIa, or Type IIIb) up to their upper critical end point (UCEP). At temperatures above the UCEP, a hydrocarbon rich liquid phase only arises for Type IIIb pseudo binary mixtures. In this region, above 647 K, correlation extrapolation options beyond the range of experimental data are discussed, and only fluid-specific Henry-like constant models are proposed. [ABSTRACT FROM AUTHOR]

Abstract: Accurate descriptions of the phase behavior and thermophysical properties of unconventional hydrocarbon resource+water mixtures are of great interest for their production, transport and refining. In this work, the phase behavior of ternary mixtures of Athabasca bitumen+toluene+water in the temperature range 473.2 to 573.5K and pressure range 2.5 to 12.6MPa are elucidated. Pressure–composition phase diagrams, solubility data for water in the hydrocarbon-rich phase, and the density of the water-saturated hydrocarbon phase are reported. Toluene+water binary exhibits Type IIIa phase behavior, where the toluene rich phase becomes critically identical with the vapor phase in the presence of a subcritical water-rich liquid phase. The Athabasca bitumen+water pseudo binary exhibits Type IIIb phase behavior, where the water-rich liquid phase becomes critically identical with the vapor phase in the presence of a subcritical bitumen-rich phase. As toluene is added to the bitumen+water mixture, there is a transition in the order of liquid–vapor criticality. Further, the hydrocarbon-rich liquid phase becomes less dense than the water-rich liquid phase as toluene is added to the mixture. The boundary for the inversion of the phase density for mixtures of Athabasca bitumen+toluene+water is evaluated as a function of toluene composition, and these and other key features of the phase behavior and phase properties discussed. [Copyright &y& Elsevier]

Abstract: With the merging of operating conditions for proposed high-temperature production and refining processes for heavy oil and bitumen, there is a growing interest in the phase behavior, thermophysical properties and reaction outcomes for water+heavy hydrocarbon resource mixtures at elevated temperatures and pressures. Athabasca bitumen, from Canada, is a commercially exploited hydrocarbon resource where 50wt.% of the material possesses a nominal boiling point exceeding 797K. In a prior publication, the phase behavior type of the Athabasca bitumen+water binary was identified experimentally as Type IIIb, according to the vanKonynenburg and Scott naming scheme. The present contribution focuses on the volume of mixing and the solubility of water in the Athabasca bitumen-rich liquid phase over the temperature interval 523–644K and over the pressure interval 3.9–26.2MPa. The measurements were obtained using a high-pressure variable-volume beryllium-walled view-cell, equipped with non-intrusive X-ray transmission tomography. X-ray tomography permits visual observation of the number of coexisting phases, and their corresponding volumes. Phase volume and density measurements were validated by reproducing published values for 1-methyl naphthalene up to 573.8K. Water solubility values were validated by reproducing data for the 1-methyl naphthalene+water and toluene+water binaries up to 573.2K and 553.2K, respectively. Measured solubility and excess volume values are also placed in a broader context by comparison with pertinent literature data. [Copyright &y& Elsevier]

Abstract: There is increasing evidence that N-methyl-d-aspartate (NMDA) receptor blockade in the neonatal period has a long-lasting influence on brain and behavior development and has been linked to an increased risk for neuropsychiatric disorders in later life. We sought to determine whether postnatal NMDA receptor blockade can affect normal development of body weight, corticosterone levels, anxiety- and depression-related behaviors in male and female mice in adulthood. For this purpose, male and female NMRI mice were treated with either saline or phencyclidine (PCP; 5 and 10 mg/kg, s.c.) on postnatal days (PND) 7, 9, and 11, and then subjected to different behavioral tests, including open field, elevated plus-maze, elevated zero-maze, light-dark box, tail suspension test and forced swimming test in adulthood. The results indicated that neonatal PCP treatment reduced body weight during neonatal and adulthood periods, and did not alter baseline corticosterone levels in both male and female mice. Moreover, this study obtained some experimental evidence showing the PCP at dose of 10 mg/kg increases stress-induced corticosterone levels, anxiety- and depression-related behaviors in males, while decreasing levels of anxiety without any significant effect on depression in female mice in adulthood. These data support the argument that neonatal NMDA receptor blockade can lead to behavioral abnormalities and psychiatric diseases in adulthood. Collectively, our findings suggest that neonatal exposure to PCP may have profound effects on the development of anxiety- and depression-related behaviors in a sex- and dose-dependent manner in mice. [Copyright &y& Elsevier]

Introduction: Ischemia/Reperfusion (IR) injury mainly causes the increase of enzymes involved in myocytes injury including CK-MB (creatine kinase-MB) isoenzyme and LDH (lactate dehydrogenase). Leakage of CK-MB isoenzyme and LDH from myocardial tissues to blood is indicator of acute myocardial infarction. The aim of this study was to assess the effect of HEMADO on IR injury and its relationship with mitochondrial ATP-sensitive K+ channels (mitoKATP) in rat heart. Methods: Twenty eight male Wistar rats (250-300g) were divided into four groups (seven members in each group): control (without ischemia), I/R (with ischemia+without HEMADO), ischemia received HEMADO (HEMADO), ischemia received HEMADO and 5-HD (5-hydroxydecanoate, specific mitoKATP channel blocker) (HEMADO+5-HD). The animals were anesthetized and the hearts were quickly removed and mounted on Langendorff apparatus and perfused by Krebs-Henseleit solution under constant pressure and temperature of 37°C. After 20 minutes of stabilization, ischemic groups were exposed to 40 minutes of global ischemia and consecutive 90 minutes of reperfusion. Results: IR injury increased the level of LDH and CK-MB in the collected coronary flow during 5 minutes since start of reperfusion. HEMADO reduced the enzymes' levels and using 5-HD abolished the effect of HEMADO. Conclusion: Our findings indicated that HEMADO could protect the heart against ischemia-reperfusion injury by decreasing the CK-MB and LDH levels. The cardioprotective effect of HEMADO may be mediated in part by mitoKATP. [ABSTRACT FROM AUTHOR]

Highlights: [•] A method for measuring the phase behavior of bitumen+water mixtures up to the critical temperature of water is presented. [•] The method is validated. [•] P − x at constant T and P − T at constant x phase diagrams are presented. [•] The phase behavior type of bitumen+water mixtures is identified. [Copyright &y& Elsevier]

Abstract: Biodiesel is one of the renewable and clean burning fuels, which can be used in diesel engines. Biodiesel is usually generated from food-grade vegetable oils using transesterification process. Using the food-grade vegetable oils is not economical since they are more expensive than diesel fuel. Therefore, it is said that the main obstacle for commercialization of biodiesel is its high cost. The kind of feedstock, which is used is the most effective factor on the biodiesel characteristics and the price. So, at first finding a proper feedstock has an important role in different places. Therefore in this research the possibility of using date seed as a cheap feedstock for biodiesel production was investigated, because it is produced largely in the hot arid regions of southwestern Asia and northern Africa. After extracting oil and producing biodiesel from Phoenix dactylifera (date seed) oil, the properties of biodiesel were evaluated by fuel standard tests and the results were compared with EN14214 and ASTM D6751 standards and also compared with the properties of produced. According to the results, the important benefit of the biodiesel from the date seed oil is high cetane number (60.3), low iodine value (46), viscosity (3.84mm2/s) and flash point (140°C) and the only weak point is its high pouring point (−1°C) which limits the use of date seed biodiesel in cold weather in comparison with other vegetable biodiesel fuels. [Copyright &y& Elsevier]

Introduction: Alzheimer's disease (AD) is a common neurodegenerative disorder in elderly people with an impairment of cognitive decline and memory loss. β-amyloid (Aβ) as a potent neurotoxic peptide has a pivotal role in the pathogenesis of AD. This disease begins with impairment in synaptic functions before developing into later neuro-degeneration and neuronal loss. The aim of this study was to evaluate the synaptic plasticity and electrophysiological function of granule cells in hippocampal dentate gyrus (DG) after intracere broventricular (i.c.v.) administration of aggregated Aβ (1-42) peptide in vivo. Methods: Animals were divided to control and Aβ (1-42) groups. Long-term potentiation (LTP) in perforant path-DG synapses was assessed in order to investigate the effect of aggregated Aβ (1-42) on synaptic plasticity. Field excitatory post-synaptic potential (fEPSP) slope and population spike (PS) amplitude were measured. Results: Administration of Aβ (1-42) significantly decreased fEPSP slope and PS amplitude in Aβ (1-42) group comparing with the control group and had no effect on baseline activity of neurons. Conclusion: The present study indicates that administration of aggregated form of Aβ (1-42) into the lateral ventricle effectively inhibits LTP in granular cells of the DG in hippocampus in vivo. [ABSTRACT FROM AUTHOR]

The enhancement of heat transfer between parallel surfaces, including parallel plates, parallel disks, and two concentric pipes, is vital because of their wide applications ranging from lubrication systems to water purification processes. Various techniques can be utilized to enhance heat transfer in such systems. Adding nanoparticles to the conventional working fluids is an effective solution that could remarkably enhance the heat transfer rate. No published review article focuses on the recent advances in nanofluid flow between parallel surfaces; therefore, the present paper aims to review the latest experimental and numerical studies on the flow and heat transfer of nanofluids (mixtures of nanoparticles and conventional working fluids) in such configurations. For the performance analysis of thermal systems composed of parallel surfaces and operating with nanofluids, it is necessary to know the physical phenomena and parameters that influence the flow and heat transfer characteristics in these systems. Significant results obtained from this review indicate that, in most cases, the heat transfer rate between parallel surfaces is enhanced with an increase in the Rayleigh number, the Reynolds number, the magnetic number, and Brownian motion. On the other hand, an increase in thermophoresis parameter, as well as flow parameters, including the Eckert number, buoyancy ratio, Hartmann number, and Lewis number, leads to heat transfer rate reduction. [Display omitted] • Nanofluid flow and heat transfer between parallel surfaces are studied. • Parallel plates, parallel disks, and concentric pipes are considered. • Physical phenomena and influential parameters are evaluated. [ABSTRACT FROM AUTHOR]

Locus coeruleus (LC) is considered to be the main source of norepinephrine in the central nervous system (CNS) and plays important role in relieving pain in the body. Changes in the activity of synaptic excitatory amino acid transporters (EAATs) would be an applicable way to regulate synaptic transmission in the LC. In the present study, we examined the role of astrocytic glutamate transporter−1 (GLT1) in the firing activity of LC neurons and the sensation of pain in rats. Male Wistar rats were divided into three control (CNT), ceftriaxone (CFT) and dihydrokainic acid (DHK) groups. Animals were given intraperitoneal injections for nine consecutive days after which the electrophysiological and behavioral experiments were performed to determine the single-unit activity of LC neurons and pain sensation. Results of this study revealed that CFT as a well−known up−regulator of GLT1 expression decreases the latency of pain sensation in rats but inhibition of GLT1 activity by DHK showed no significant effects. Furthermore, the results obtained by single-unit recording from LC showed a significant decrease in evoked response in CFT group compared to the CNT group. Therefore, this study suggests that GLT1 might be considered as a potential therapeutic target for pain modulation in the future. [ABSTRACT FROM AUTHOR]

Achieving high voltage levels is an important issue in the design of multi-level inverters (MLIs). In this paper, the basic unit of a new switched-capacitor (SC) topology is extended to achieve higher voltage levels with fewer components. The capacitors are charged from the single supply voltage directly by turning on appropriate switching states, which can generate a high-amplitude nearly sinusoidal output voltage. The operating principles, modulation strategy, method of determining capacitance, and power loss of the extended structure are presented in detail. Also, a comparative study with recent similar structures has been done. The extended SCMLI has the advantages of self-balancing the voltage of the capacitors, generating a bipolar output voltage, and satisfying the standard of harmonics (IEEE519). The experimental test and MATLAB simulation results of a 17-level prototype are given to verify the performance of the extended structure. [ABSTRACT FROM AUTHOR]

Background: It is unknown if the clinical manifestations and phenotype of disease are comparable between early- and elderlyonset inflammatory bowel disease (IBD). We aimed to seek differences in disease phenotype, course, complications, and treatment between early- and elderly-onset IBD patients. Methods: This retrospective cohort study on registered IBD patients in the Iranian Registry of Crohn's and Colitis (IRCC) compared demographics, disease phenotype, disease activity, IBD-related surgery and medications between early- and elderly-onset IBD. A generalized linear regression model was used to investigate the relative risk of age at diagnosis adjusted for gender and disease duration for the outcomes. Results: From 10 048 IBD patients, 749 with early-onset (7.5%), and 472 (4.7%) elderly-onset IBD were enrolled: 855 (63.1%) ulcerative colitis (UC) and 366 (26.9%) Crohn's disease (CD). Left-sided colitis was more frequent among elderly-onset UC patients (P < 0.001). Ileum and ileocolonic locations were the most common types in elderly-onset and early-onset CD patients, respectively. In comparison with elderly-onset UC, early-onset cases more often used prednisolone (22.1% vs. 11.4%, P = 0.001), immunomodulators (44.9% vs 25.2%, P < 0.001) and anti-tumor necrosis factors (TNF) (20.1% vs 11.9%, P = 0.002). Elderly-onset UC patients had 0.7 times lower risk of aggressive phenotype (95%CI:0.6-0.9, P = 0.005). Early-onset CD was associated with higher use of prednisolone (27.7% vs 8.1%, P < 0.001), immunomodulators (58.7% vs 41.8%, P = 0.005) and anti-TNF (49.6% vs 35.4%, P = 0.006). Conclusion: Early-onset IBD was associated with a more aggressive phenotype and higher prednisolone, immunomodulators, and anti-TNF use. [ABSTRACT FROM AUTHOR]

Irreversibility factors for the TiO2–water nanofluid flow are evaluated through entropy generation rates caused by friction and heat transfer by taking into account nanoparticle migration. Effects of three factors of viscosity gradient, non-uniform shear rate and Brownian diffusion are considered. The investigations are performed in both conventional channels and minichannels since the channel size has the considerable effects of on entropy generation. Influence of particle migration on the irreversibility factors is more noticeable in smaller channels such that with considering particle migration, the maximum thermal entropy generation rate increases about 51% for 0.2 mm channel, while this increment is almost 16% for 1 mm channel. Unlike results are obtained for conventional channels and minichannels, such that total entropy generation intensifies in minichannels and reduces in conventional channels by particle concentration increment. Friction is main factor in entropy generation for minichannels, while heat transfer demonstrates a higher contribution in conventional channels. The optimal channel size where minimum entropy generation occurs is obtained which is dependent on Reynolds number. Therefore, for lower Reynolds number, optimal case occurs at smaller channel size. Furthermore, diagrams of total entropy generation show minimum (optimal) point for 3 mm channel, while they demonstrate the constant trends for other channels. [ABSTRACT FROM AUTHOR]

Abstract Asphaltene deposition in the near well bore region, tubing and surface facilities causes chronic problems in oil industry. Mechanical, thermal and chemical approaches are frequently being used but each suffers from certain limitations and shortcomings. The utilization of such methods also comes usually with a large price tag as these require mechanical equipment, pumps, new completion and tubing, solvents and chemical materials. Needless to say that these are often performed during well shutdown. The choice of optimal production operating conditions which otherwise would prevent or diminish asphaltene deposition is preferential. In previous studies, producing with low bottom hole pressure (BHP) has been proposed as a viable solution for some of asphaltenic oil fields, but a thorough and detailed study is still lacking. In this study, a comprehensive simulation methodology is developed to tackle impacts of BHP conditions on the asphaltene deposition. An IMPES (Implicit Pressure and Explicit Compositions) cylindrical, compositional simulator is developed which considers asphaltene deposition dynamically. Precipitated asphaltene is considered as a pure dense liquid which is determined by LLE calculation using PR-EoS. The amount of deposition is obtained through three mechanisms of surface deposition, entrainment and pore throat plugging. The permeability reduction is correlated with porosity reduction using a power-law relation. Detailed analysis of the simulated cases reveals that selecting a very low BHP (bellow bubble point pressure) would maintain the reservoir in a desirable pressure range far from the maximum deposition point. Highlights • A comprehensive simulation methodology to demonstrate the impacts of BHP conditions on the asphaltene deposition. • Developing an IMPES cylindrical, compositional simulator to consider asphaltene deposition dynamically. • Describing pressure behavior of reservoir around wellbore with considering asphaltene deposition. • Giving recommendations for flow assurance applications. [ABSTRACT FROM AUTHOR]

Abstract Modeling and simulation of nanofluid flows is crucial for applications ranging from the cooling of electronic devices to solar water heating systems, particularly when compared to the high expense of experimental studies. Accurate simulation of a thermal-fluid system requires a deep understanding of the underlying physical phenomena occurring in the system. In the case of a complex nanofluid-based system, suitable simplifying approximations must be chosen to strike a balance between the nano-scale and macro-scale phenomena. Based on these choices, the computational approach – or set of approaches – to solve the mathematical model can be identified, implemented and validated. In Part I of this review (Mahian et al., 2019), we presented the details of various approaches that are used for modeling nanofluid flows, which can be classified into single-phase and two-phase approaches. Now, in Part II, the main computational methods for solving the transport equations associated with nanofluid flow are briefly summarized, including the finite difference, finite volume, finite element, lattice Boltzmann methods, and Lagrangian methods (such as dissipative particle dynamics and molecular dynamics). Next, the latest studies on 3D simulation of nanofluid flow in various regimes and configurations are reviewed. The numerical studies in the literature mostly focus on various forms of heat exchangers, such as solar collectors (flat plate and parabolic solar collectors), microchannels, car radiators, and blast furnace stave coolers along with a few other important nanofluid flow applications. Attention is given to the difference between 2D and 3D simulations, the effect of using different computational approaches on the flow and thermal performance predictions, and the influence of the selected physical model on the computational results. Finally, the knowledge gaps in this field are discussed in detail, along with some suggestions for the next steps in this field. The present review, prepared in two parts, is intended to be a comprehensive reference for researchers and practitioners interested in nanofluids and in the many applications of nanofluid flows. [ABSTRACT FROM AUTHOR]

Abstract It has been more than two decades since the discovery of nanofluids-mixtures of common liquids and solid nanoparticles less than 100 nm in size. As a type of colloidal suspension, nanofluids are typically employed as heat transfer fluids due to their favorable thermal and fluid properties. There have been numerous numerical studies of nanofluids in recent years (more than 1000 in both 2016 and 2017, based on Scopus statistics). Due to the small size and large numbers of nanoparticles that interact with the surrounding fluid in nanofluid flows, it has been a major challenge to capture both the macro-scale and the nano-scale effects of these systems without incurring extraordinarily high computational costs. To help understand the state of the art in modeling nanofluids and to discuss the challenges that remain in this field, the present article reviews the latest developments in modeling of nanofluid flows and heat transfer with an emphasis on 3D simulations. In part I, a brief overview of nanofluids (fabrication, applications, and their achievable thermo-physical properties) will be presented first. Next, various forces that exist in particulate flows such as drag, lift (Magnus and Saffman), Brownian, thermophoretic, van der Waals, and electrostatic double layer forces and their significance in nanofluid flows are discussed. Afterwards, the main models used to calculate the thermophysical properties of nanofluids are reviewed. This will be followed with the description of the main physical models presented for nanofluid flows and heat transfer, from single-phase to Eulerian and Lagrangian two-phase models. In part II, various computational fluid dynamics (CFD) techniques will be presented. Next, the latest studies on 3D simulation of nanofluid flow in various regimes and configurations are reviewed. The present review is expected to be helpful for researchers working on numerical simulation of nanofluids and also for scholars who work on experimental aspects of nanofluids to understand the underlying physical phenomena occurring during their experiments. [ABSTRACT FROM AUTHOR]

This research presents a combination of thermo-economic analysis and multi-objective optimization of a 10 kW single-effect ammonia-water solar absorption cooling system. A thermodynamic model is derived, and energy-exergy analyses are conducted. Also, the effects of various solar collector types including a flat plate, evacuated tube, compound parabolic, and parabolic trough collectors on the system performance are examined at different ambient temperatures. The thermodynamic analysis indicates that by increasing heat source temperature, the coefficient of performance and exergy efficiency of the system reach their highest values, while they occur in lower heat source temperature as the ambient temperature is decreased. The exergy efficiency is also found to decrease with the increment of evaporator, absorber, and condenser absorber temperatures. Furthermore, for determining the optimum operating conditions, a multi-objective optimization is performed by using an efficient particle swarm optimization technique with five objective functions. The corresponding results reveal that the solar absorption cooling system with evacuated tube collectors is the most economical solution with a total cost of 7.2 k€ and 24 m 2 collector area. It is found that the parabolic trough collector system has the highest solar exergy efficiency of 0.046, which occurs at the high ambient temperature and low evaporator temperature. This system also has higher solar performance coefficient up to 0.447 indicating its great efficiency. [ABSTRACT FROM AUTHOR]

The second law attributes including entropy generation, exergy destruction and second law efficiency for flow a novel nanofluid containing graphene nanoplatelets decorated with silver nanoparticles are investigated in a micro double-pipe heat exchanger. The effects of viscous dissipation are considered in the simulation. Frictional entropy generation intensifies with increase in Reynolds number and concentration. Moreover, with the concentration increment, thermal entropy generation rate increases. The frictional and thermal exergy destruction rates intensify in both tube and annulus sides by increasing either Reynolds number or concentration. The results show that the friction has a more significant role than heat transfer in exergy destruction occurred in the heat exchanger. By increasing the Reynolds number, contribution of the nanofluid side to the exergy destruction increases in comparison with that of the water side. In addition, the second law efficiency decreases by increasing either Reynolds number or concentration. [ABSTRACT FROM AUTHOR]