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Introduction: Hemodialysis is a crucial treatment for patients with chronic renal failure. Despite its effectiveness in managing end-stage renal failure, hemodialysis patients face multiple physical and psychological stressors. Recognizing the interconnectedness of body and soul, religious and spiritual views can potentially provide valuable support. Previous research has indicated that spiritual beliefs impact patients’ health and self-esteem. This study surveys the relationship between spiritual intervention and self-esteem in hemodialysis patients in the Iranian population. Material and methods: The study is semi-experimental and involves 44 hemodialysis patients in Kermanshah in 2016. After convenience sampling, the patients were divided into two groups, control (22 patients) and intervention (22 patients), using random allocation. For the intervention group, spiritual-religious sessions lasting 45-60 minutes were scheduled twice a week in a group format. Inclusion criteria for participation included being 18 years or older, having undergone hemodialysis for at least 6 months, and providing informed consent. Data collection involved assessing demographic features and using the Coppersmith Self-Esteem Scale. Finally, the data were analyzed using the independent sample t-test, Fisher’s exact test and the chi-square test. P < 0.05 was considered as statistically significant. Results: Before the intervention, mean self-esteem in the intervention group was 23.80 ±1.99. Mean self-esteem in the control group was 23.85 ±2.03. After the intervention, mean self-esteem in the intervention group increased significantly to 37.28 ±2.53 after the spiritual-religious intervention (p < 0.05). Mean self-esteem in the control group remained relatively stable at 23.42 ±1.88 (p > 0.05). Conclusions: The findings suggest that spiritual-religious sessions have a positive effect on the self-esteem of hemodialysis patients. Incorporating spiritual care into the patients’ overall care program may contribute to improving their self-esteem. Therefore, recognizing the holistic needs of patients, including their spiritual well-being, can enhance patients’ self-esteem during the challenging process of hemodialysis. [ABSTRACT FROM AUTHOR]

• MD simulation was performed to explore the effect of PEG concentration on drug release from PLA-PEG copolymers. • PEG-PLA-PEG copolymers with 8.7 wt% of PEG exhibited the highest drug release rate due to quicker water penetration. • The copolymer type and chain length were found to impact water molecule access to PEG and drug release rate significantly. Mercaptopurine (6-MP), a cancer medication limited by its hydrophobic properties, was studied using molecular dynamics simulations with biodegradable copolymers (PLA-PEG, PLA-PEG-PLA, PEG-PLA-PEG) as drug carriers. The influence of PEG concentration in copolymers on drug release was examined. Results revealed that blending PEG with PLA or copolymerizing them affected hydrogen bond numbers and mixing energy in the drug carrier, dependent on copolymer type and PEG concentration. Introducing PEG into PLA chains increased hydrogen bonds and energy, but copolymerizing PLA and PEG did not consistently enhance hydrogen bond energy (PLA-PEG-PLA > PEG-PLA-PEG > PLA-PEG). Mixing energy was consistently elevated by PEG-PLA copolymerization, ranked PEG-PLA-PEG > PLA-PEG > PLA-PEG-PLA. The fastest drug release was observed with the PLA&PEG-10.9 carrier, attributed to weak PLA-PEG chain connections facilitating water access to PEG. Increasing PEG content reduced chain mixing energy, slowed drug release via stronger chain hydrogen bonding. Notably, PEG-PLA-PEG-8.7 exhibited the highest drug release rate due to quicker water penetration. The copolymer type and chain length were found to impact water molecule access to PEG and drug release rate significantly. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations are performed to study the design and optimization of nanocarriers with high drug loading capacity. Functionalized graphene is considered as the nominated high capacity drug carrier and Dox as the drug model. The graphene surface functionalized with hydroxyl (– O H ), carboxyl (– C O O H ), methyl (– C H 3 ) and amine (– N H 2 ) groups and their associated properties are investigated. The simulation results are illustrated that G − C O O H surface absorbs Dox more effectively in comparison to other functionalized graphene surfaces due to the higher binding energy of carboxylic groups and the model drug. The effect of hydrogen bonding, temperature and surface porosity are also evaluated. The results show that binding energy and the solubility parameter are temperature-dependent. The simulation results in this present work reveal the underlying mechanisms of Dox loading on neat and functionalized graphene surfaces may be employed to design better graphene-based nanocarriers for the Dox delivery applications. [ABSTRACT FROM AUTHOR]

In this work, cationic (Mg, Ca, Sr, and Ba) substitution in X and Y faujasite zeolite structures and their effects on capacity of zeolites for methane adsorption were studied by applying multiple linear regression and expert adaptive neuro-fuzzy inference system (ANFIS) . Temperature, pressure, and molecular weight of cations were used as the input parameters. The results obtained from application of the proposed ANFIS model showed that at high pressures, the zeolite with smaller cation in their structure have higher methane adsorption capacity. The root-mean-square error, square correlation coefficient ( R ), mean absolute error, and percentage of mean absolute relative error for X and Y faujasite zeolites were evaluated, which indicated that ANFIS model can accurately predict the adsorption of methane gas on X and Y zeolites in the presence of the substituted cations. [ABSTRACT FROM AUTHOR]

Highlights: [•] The adsorption and separation properties of new siliceous zeolites were investigated. [•] The force fields of COMPASS, PCFF, CVFF, DREIDING and Universal were used in the GCMC. [•] The PCFF is the best force field for simulation of adsorption in zeolites. [•] RWY zeolite is the best zeolite types for the separation of binary mixture. [Copyright &y& Elsevier]

The adsorption isotherm of hydrogen in zeolites FAU, LTA, KFI, RWY, RHO and TSC has been simulated employing grand canonical Monte Carlo procedure for a temperature range of 77 to 95 K and different pressures. The effects of structural composition, unit cell volume, framework density and specific surface area of zeolite on hydrogen adsorption in zeolites were investigated. The results clearly show that the adsorption of hydrogen in zeolites with the same silica density is a function of oxygen density at low pressures, and it is approximately the same at intermediate pressures. Nevertheless, at high pressures, the adsorption of hydrogen is a function of pore diameter for zeolites with same silica density. The effect of specific surface area on the adsorption isotherm of hydrogen on zeolites with approximately the same specific surface area is significant at low and high pressures. The results clearly indicate that the adsorption of hydrogen in RWY zeolite has maximum value at 77 K and at high pressures. The optimum condition of pressure for hydrogen adsorption isotherm in RWY zeolite is determined to be 600 bar. At a temperature of 77 K and a pressure of 600 bar, the adsorption of hydrogen in RWY zeolite is 6.93 wt %. [ABSTRACT FROM AUTHOR]

Abstract: Structural, physical and separation properties of polyurethane membrane were investigated by configuration bias grand canonical Monte Carlo and molecular dynamic methods and the effects of degree of polymerization on these properties were studied. To understand the effect of degree of polymerization of polyurethane membrane on its separation property, the adsorption of furfural as pure and binary mixture with water was studied for polyurethane membrane with varied degrees of polymerization from 5 to 100. The temperature range for simulation calculation was 298 K–360 K and the pressure range was 0–10 bar. Also the effects of feed composition, density and free volume of polyurethane membrane on its separation property were studied. It was found that the adsorption of furfural and water in polyurethane membrane depends on free volume of polyurethane and this dependency is more significant for the adsorption of water molecule. The results indicate that the maximum adsorption of furfural and water occurs on polyurethane membrane with polymerization degree of 10. [Copyright &y& Elsevier]

Abstract: Grand Canonical Monte Carlo simulation is used to study adsorption of nitrogen on new type of zeolites such as IHW, IWV, SIV, UFI, and MSE at temperature range 273–325K and pressures up to 50bars. The optimum parameters of Lennard–Jones potential are evaluated and their effects on the simulation results are examined. Besides, the effects of temperature, pressure, framework density (FD) and oxygen density in unit cell on the adsorption isotherms are investigated. Although, the adsorption of nitrogen is a complex function of pressure, temperature, and pore structure of zeolite, it is found that, at room temperature, the adsorption increases linearly with increasing pressure. The results show that IWV type of zeolite gives the greatest adsorption at sufficiently high pressure. At low pressure, the effect of oxygen density in simulation box on the adsorption isotherms is higher than pore diameter. At high pressure, the effect of temperature on the adsorption isotherm does not depend on structural composition of zeolites. [Copyright &y& Elsevier]

Abstract: Zeolites belong to a most prominent class of nanoporous materials which have been considered as potential sorbents for hydrogen storage. The adsorption of hydrogen molecules on purely siliceous zeolites such as ACO, MEP, ASV, ANA, RWY, and RHO, which encompass a range of different pore structures and their chemical compositions has been simulated employing Grand Canonical Monte Carlo (GCMC) procedure for a temperature range of 250–325K, and a pressure range of 0–10kbar. The effects of pore structure of zeolites, temperature and pressure on the hydrogen adsorption has been examined. The results clearly show that the number of adsorbed hydrogen molecules at high pressure, only depends on pore diameter, and the temperature effect on the adsorption decreases with decrease in the number of adsorbed of hydrogen molecules. [Copyright &y& Elsevier]

[Display omitted] • The aggregation of N9 asphaltene molecules in aromatic solvents are investigated. • N9 molecules tend to aggregate due to OH groups and π-π bonds between their carbon rings. • The solvents with high electronegativity atoms prevent N9 molecules from being close to each other. • The tendency of asphaltene to aggregate is decreased with increasing alifatic chains in the structure. The aggregation of N9 asphaltene molecules in aromatic solvents were investigated using molecular dynamics simulation at ambient temperature and pressure. The simulation results show that N9 asphaltene molecules have tendency to aggregate and be close to each other due to OH groups and π-stacking interactions between their carbon rings. The N9 asphaltene molecules behave differently in these aromatic solvents, as in phenols, they are completely soluble, and in isopropylbenzene, they approach each other. This investigation's results confirm the molecular structure influence of poly aromatic compounds, heteroatoms and aliphatic chains on their aggregation mechanism. [ABSTRACT FROM AUTHOR]

• Reverse non-equilibrium molecular dynamics simulations (RNEMD) is used to investigate thermal conductivity of Polyamide 6. • Thermal conductivity of Polyamide 6 increases with the Degree of Polymerization (DOP) and reaches a constant value at high DOPs. • Polydispersity Index (PDI) does not have a significant influence on the thermal conductivity of the Polyamide 6. • The thermal conductivity increases linearly with the density. • The thermal conductivity is highly affected by the Fraction of Free Volume (FFV) of the system. In this study, the influence of both molecular weight (expressed as the degree of polymerization (DOP)) and Polydispersity index (PDI) on the thermal conductivity of Polyamide 6 (Nylon 6) were investigated by means of reverse non-equilibrium molecular dynamics simulations (RNEMD). At first, physical properties such as density and the solubility parameter were calculated to confirm the accuracy of the simulation results. Afterwards, variations in thermal conductivity with DOP and PDI were investigated. The simulation results show that the thermal conductivity of Polyamide 6 is 0.25 ± 0.002 W/(mK) which is in good agreement with the experimental data of 0.24–0.25 W/(mK). In addition, based on the simulation results, the thermal conductivity of Polyamide 6 has increased with the DOP and a plateau has been achieved at high DOPs. It was observed that varying PDI does not have a significant effect on the thermal conductivity at a constant value of average molecular weight. The dependency of thermal conductivity to the polymer density was also investigated and it was observed that by enhancing the polymer density, the thermal conductivity increases linearly. It was also concluded that the thermal conductivity is severely affected by system's fraction of free volume. [ABSTRACT FROM AUTHOR]

The conductivity and diffusion of hydronium ions at 298 K in PVA (Polyvinyl alcohol), PBI (Polybenzimidazole) and SPEEK (Sulfonated polyether ether ketone) as known membranes of PEMFCs have been investigated using molecular dynamics simulation method throughout this work. The simulation results show that the diffusion of hydronium ions in these polymer membranes depends on the polymer structure and water concentration in the membrane. On the other hand, RDF analysis results also show that the tendency of hydronium ions to polymer atoms strongly depends on the water concentration. So their tendency to polymer chains decreases with increasing the water concentration in PBI and PVA. Based on the results of this investigation, the conductivity of hydronium ions in PVA is more than the two other membranes (=19.83 ms/cm in 30 wt % of water). • The conductivity and diffusion of hydronium ions in PVA, PBI and SPEEK membranes are investigated • The diffusion of hydronium ions in membrane depends on the polymer structure and water concentration • The conductivity of hydronium ions in PVA is more than the two other membranes in 30 wt. % of water [ABSTRACT FROM AUTHOR]

The absorption and release of 6-mercaptopurine anticancer drug was investigated in biodegradable and biocompatible polymer of polylactic acid (PLA) using molecular dynamics simulation. For this purpose, the amount of mixing energy, radius of gyration, mean squared displacement and radial distribution function were computed and compared in concentrations of 5–36 wt% of 6-mercaptopurine drug. The simulation results show that increasing the concentration of the drug reduces mixing energy and PLA polymer carrier is able to carry 35.8 wt% of 6-mercaptopurine anticancer drug. Based on these results, the amount of 6-mercaptopurine release from PLA carrier 35.8 wt% of it in water environment is zero due to hydrophobic property of PLA and 6-mercaptopurine. Finally, polyethylene glycol (PEG) polymer with different percentages (10–30 wt%) was used to modify PLA carrier. The simulation results show that the rate of drug release increases by increasing the concentration of PEG polymer in the modified PLA carrier and also with increasing the percentage of drug loaded in the carrier and also the optimum weight percentage of PEG in modified PLA carrier for 35.8 wt% of drug concentration is 11 wt% and the rate of drug release is slower and equal to 4.4 molecules/ns. • Simulation of absorption and release of 6-mercaptopurine drug in PLA carrier • PLA polymer carrier is able to carry 35.8 wt% of 6-mercaptopurine anticancer drug. • The drug release from PLA carrier it in water environment is zero. • Simulation of modified PLA carrier with PEG polymer with 10–30 wt%. • The drug release increases in the presence of PEG polymer in the modified PLA carrier. [ABSTRACT FROM AUTHOR]

• Addition of BaCeO 3 nanoparticle to membrane improves the proton conductivity of PVA, PBI and SPEEK nanocomposite membranes. • The percentage Y doped in BaCeO 3 is important for the proton conductivity in the PVA, PBI and SPEEK membranes. • The proton conductivity in the SPEEK membranes improves 1200 percent with of 29% Y doped BaCeO 3. Molecular dynamics simulation method was used to study the effect of BaCeO 3 nanoparticles on proton conductivity enhancement in nanocomposite membranes of PVA (Polyvinyl alcohol), PBI (Polybenzimidazole) and SPEEK (Sulfonated polyether ether ketone). The simulation results indicated that the addition of BaCeO 3 nanoparticles to polymeric membranes cause to increase diffusion coefficient of hydronium ions 1.5, 1.5 and 3.5 times more than their diffusivity in pure polymer membranes of PBI, SPEEK and PVA, respectively. The results of the radial distribution function analyses show that the addition of nanoparticles to polymeric membranes decreases the interaction between polymer chains and hydronium ions. In addition, the effect of Y atomic percentage doped in BaCeO 3 nanoparticles with 14%, 29% and 43% was investigated for more improvement of the proton conductivity of the nanocomposite membranes. It was found that the increase of Y atomic percentage doped in BaCeO 3 nanoparticles reduces the diffusion coefficient of hydronium ions in PVA membrane. It is also considerable that the addition of 43% of Y doped in BaCeO 3 nanoparticles improves the conductivity of hydronium ions in PBI nanocomposite membranes with 40%. [ABSTRACT FROM AUTHOR]

• Contradictory results exist regarding the impact of intergenerational instrumental support. • Emotional and financial support associate with older adults' depression. • Positive intergenerational relationships linked to lower depressive symptoms in older adults. This systematic review aims to comprehensively examine the relationship between intergenerational relationships and depression among older adults in Eastern Asian countries. For this research, a systematic search was conducted on several electronic databases including PubMed, Scopus, Web of Science, ScienceDirect, and Google Scholar search engine up until June 2023. Out of 953 articles initially identified, 33 met the inclusion criteria. Emotional support and financial support emerged as crucial factors that can significantly reduce depressive symptoms among older individuals. However, there are diverse and sometimes contradictory results regarding the impact of intergenerational instrumental support on depression in older adults. Promoting positive intergenerational relationships and enhancing support systems can greatly benefit the mental health of older adults by addressing depression within this population. This review enhances our understanding of the complex relationship between intergenerational relationships and depression among older adults. The diverse findings on intergenerational instrumental support and depression in older adults suggest the need for further research to clarify this relationship and its nuances. This research may have practical implications for policies and interventions aimed at improving the mental well-being of older adults in Eastern Asian countries. [ABSTRACT FROM AUTHOR]

The use of highly toxic solvents presents significant risks to both the environment and human health. Therefore, the adoption of green solvents will be crucial for achieving sustainable membrane production. This work reports the use of inexpensive environmentally friendly biobased and biodegradable cyclic carbonate solvents, namely ethylene carbonate (EC), propylene carbonate (PC), and butylene carbonate (BC), to fabricate polyvinylidene fluoride (PVDF) membranes. The solvent dependence of the phase inversion mechanisms, morphology, crystalline structures, and polymorphism of the prepared PVDF membranes were investigated. Polymorph analysis revealed that membrane fabrication in EC or PC yielded exclusively the β-phase product, whereas PVDF membrane fabrication in BC yielded a mixture of α and β phase material. The mechanism of β-phase formation was investigated using molecular dynamics simulation and shown to depend on the extent of hydrogen bonding at the polymer–solvent interface. The PVDF membrane formed in EC exhibited the highest porosity and pure water permeability, and was therefore tested in direct contact membrane distillation (DCMD), exhibiting promising results in terms of permeate flux and salt rejection. These results suggest that large-scale production of piezoelectric PVDF membranes using green solvents should be practically feasible. [ABSTRACT FROM AUTHOR]

Background: The rate of attempting suicide is growing due to the increasing social and economic problems and a variety of stresses taken by individuals in their lives. Helping people, boosting hope, and improving resilience to life hardships might be helpful in this area. This paper is an attempt to determine the effects of group reminiscence on hope and resilience in care-seekers who have attempted suicide. Method: The study was carried out as a quasi-experimental interventional study. The participants were 57 care-seekers with a history of attempting suicide who met the inclusion criteria. The sampling was done through convenience sampling and the participants were grouped into control (n = 29) and experimental (n = 28) groups randomly. The experimental group received integrated reminiscence sessions (eight sessions; 60–90 min). Hope and resilience of the subjects were measured using Schneider's Hope Scale and Connor and Davidson's Resilience Scale. The scales were filled out by the subjects before, immediately after, and 4 weeks after the intervention. Results: The mean scores of hope in the experimental and control groups were 34.60 and 38.04, respectively, before the intervention. These figures immediately after the intervention were 44.07 and 35.96 in the experimental and control groups, respectively. 4 weeks after the intervention, the mean scores of hope in the experimental and control groups were 44.39 and 35.79, respectively, which is a statistically significant difference (p < 0.05). In terms of resilience, the mean scores in the experimental and control groups before the intervention were 48.17 and 57.51, respectively; and immediately after the intervention, these figures were 67.71 and 52.75, respectively. 4 weeks of the intervention, the mean scores of resilience were 59.17 and 52.24, respectively, which is a statistically significant difference (p < 0.05). Conclusion: Group reminiscence has a positive effect on boosting hope and resilience in care-seekers who have attempted suicide. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DES) have recently emerged as a new class of inexpensive biodegradable solvents and additives with diverse applications. In this study, a new family of non-ionic deep eutectic solvents (NIDES) is proposed for the first time for membrane preparation. Three types of NIDES, N-methylacetamide-acetamide (DES-1), N-methyl acetamide-N-methyl urea (DES-2), and N-methyl acetamide-N,N′-dimethyl urea (DES-3) were synthesized and used to dissolve polyvinylidene fluoride (PVDF) polymer. The effects of the additive polyvinylpyrrolidone (PVP) and the type of NIDES on the PVDF membrane characteristics, water permeability and bovine serum albumin (BSA) separation were studied. The membranes prepared with DES-1 and 2 wt% PVP exhibited a good water permeate flux (96.82 L/m2.h) and a high BSA separation factor (96.32%). High performance PVDF membranes can thus be efficiently prepared using biodegradable inexpensive NIDES. [Display omitted] • Deep eutectic solvents, DES, are a viable option for membrane formation. • Designed non-ionic deep eutectic solvents, NIDES, dissolve PVDF at high temperatures. • PVP improved BSA filtration performance of PVDF membranes prepared with NIDES. • High filtration performance PVDF membranes can be prepared using NIDES. • NIDES are promising scalable and inexpensive candidates to use in membrane preparation. [ABSTRACT FROM AUTHOR]

Objectives: The cognitive function of older adults is an important indicator of healthy aging. Living arrangements have been identified as a potentially important factor affecting cognitive function among older adults. This study investigated the relationship between living arrangements and cognitive function among older adults aged 65 years and older in Kermanshah City, Iran.The cross-sectional study design was used in this study. Participants aged 65 years and older in Kermanshah City, Iran were recruited for the study. The Neuropsychiatric Unit Cognitive Assessment (NUCOG) was used to assess cognitive function, and demographic information was collected to assess living arrangements.The study found that cognitive function was generally within the normal range among older adults, and that age, education level, and living arrangements were significantly associated with cognitive performance.These results highlight the importance of considering demographic factors when developing interventions aimed at promoting cognitive health among older adults.Methods: The cognitive function of older adults is an important indicator of healthy aging. Living arrangements have been identified as a potentially important factor affecting cognitive function among older adults. This study investigated the relationship between living arrangements and cognitive function among older adults aged 65 years and older in Kermanshah City, Iran.The cross-sectional study design was used in this study. Participants aged 65 years and older in Kermanshah City, Iran were recruited for the study. The Neuropsychiatric Unit Cognitive Assessment (NUCOG) was used to assess cognitive function, and demographic information was collected to assess living arrangements.The study found that cognitive function was generally within the normal range among older adults, and that age, education level, and living arrangements were significantly associated with cognitive performance.These results highlight the importance of considering demographic factors when developing interventions aimed at promoting cognitive health among older adults.Results: The cognitive function of older adults is an important indicator of healthy aging. Living arrangements have been identified as a potentially important factor affecting cognitive function among older adults. This study investigated the relationship between living arrangements and cognitive function among older adults aged 65 years and older in Kermanshah City, Iran.The cross-sectional study design was used in this study. Participants aged 65 years and older in Kermanshah City, Iran were recruited for the study. The Neuropsychiatric Unit Cognitive Assessment (NUCOG) was used to assess cognitive function, and demographic information was collected to assess living arrangements.The study found that cognitive function was generally within the normal range among older adults, and that age, education level, and living arrangements were significantly associated with cognitive performance.These results highlight the importance of considering demographic factors when developing interventions aimed at promoting cognitive health among older adults.Discussion: The cognitive function of older adults is an important indicator of healthy aging. Living arrangements have been identified as a potentially important factor affecting cognitive function among older adults. This study investigated the relationship between living arrangements and cognitive function among older adults aged 65 years and older in Kermanshah City, Iran.The cross-sectional study design was used in this study. Participants aged 65 years and older in Kermanshah City, Iran were recruited for the study. The Neuropsychiatric Unit Cognitive Assessment (NUCOG) was used to assess cognitive function, and demographic information was collected to assess living arrangements.The study found that cognitive function was generally within the normal range among older adults, and that age, education level, and living arrangements were significantly associated with cognitive performance.These results highlight the importance of considering demographic factors when developing interventions aimed at promoting cognitive health among older adults. [ABSTRACT FROM AUTHOR]

Background: In addition to physical, mental, and social condition, ESRD and hemodialysis affect the quality of life of patients as well. Psychotherapy and non-pharmaceutical interventions are effective measures to add meaning to life, create a goal and motivation in life, and improve the quality of life in chronic patients. The effect of educational and supportive group therapy on the quality of life (QOL) of hemodialysis patients was examined. Methods: The study was carried out as an interventional quasi-experimental study with the participation of 64 patients who were selected through convenience sampling and based on the patient's hemodialysis days (Saturday, Monday, and Wednesday patients as an experimental group and Sunday, Tuesday, and Thursday patients as a control group). There were 32 patients in each group. The experimental group received eight 50 min sessions including two sessions per week. The control group received the normal interventions. The participants were assessed using a demographics form and Kidney Disease Quality of Life Short Form before, immediately after, and 1 month after the intervention. The collected data was analyzed using SPSS (v.24). Results: The mean QOL scores of the experimental group before, immediately after, and 4 weeks after the intervention were 36.99, 43.3, and 44.9 respectively. Those of the control group were 36.39, 37.2, and 37.1 respectively. There was no significant difference between the two groups before the intervention (P > 0.05); however, the difference between the two groups was significant immediately after and 4 weeks after the intervention (P = 0.0001). The trend of score change in the experimental group was also significant (p < 0.05), and Tukey ad-hoc test showed significant differences between the scores before intervention and those immediately after and 4 weeks after the intervention (p < 0.05). Conclusion: In general, educational and supportive group therapy can expand the interpersonal relationships of hemodialysis patients and positively affect their quality of life. [ABSTRACT FROM AUTHOR]

• MD simulation was applied to study the kinetics of methane hydrate growth. • A kinetics model based on the non-equilibrium thermodynamics was considered. • Two-parametric model had a constant parameter in all the operational conditions.. • The hydrate formation is a process proceeding on a natural path. In the present work, the molecular dynamic simulation was applied for studying the kinetics of methane hydrate growth. Several parameters such as the changes of potential energy, the MSD of molecules, the number of methane molecules near the solid/liquid interface and the position of liquid/solid interfaces with time were considered. The results showed that the potential energy and MSD of molecules in the layers near the interfaces significantly decreases implying that the growth proceeds in these layers. The maximum rate of growth or migration of methane molecules to the interfaces is observed around 2 ns. Moreover, a kinetics model was considered to predict hydrate growth kinetics. It is based on the irreversible and non-equilibrium thermodynamics and the concept of the thermodynamic natural path. The proposed model is a two-parametric model that one parameter was estimated to be a nearly constant value in the range from −1.05 to 1.46, but another one is a kinetic parameter dependent on the operational conditions. The model can well predict the entire process of hydrate formation, since the affinity, as a driving force of the process, shows that the hydrate formation is a process proceeding on a natural path. [ABSTRACT FROM AUTHOR]

In this research, molecular dynamics (MD) simulation was performed to explore the proton conductivity performance of three different sulfonated polybenzimidazole (SPBI) polymers with the same backbone but different functional groups as proton exchange membranes. To date, there are a few published experimental works on different SPBI polymer membranes. However, those studies were in profound disagreement about the positive effect of pendant functional groups attached to the backbone on PBI performance; therefore, MD simulations were required to resolve the conflicts. By comparisons of the simulated solubility parameter and glass transition temperature with the experimental measurements, it was initially determined that a simulation box made up of three chains of the polybenzimidazole polymer—each comprising of 30 monomers—was an appropriate simulation box for amorphous materials. Additionally, mean square displacement was used to analyze the dynamics of the self-diffusion coefficients. The calculated diffusion coefficients were 2.0 × 10−6, 1.4 × 10−6, and 1.1 × 10−6 cm2/s for PBI-S (SO 3 H PBI), PBI-PS (propylsulfonate PBI), and PBI-AS (arylsulfonate PBI), respectively. Based on the results, it was understood that the simulated proton conductivities were comparable with the results obtained by some researchers and consequently against other conflicting claims. The calculated proton conductivities are 13.1, 7.8, and 5.7 mS/cm for PBI-S, PBI-PS, and PBI-AS, respectively. Moreover, the examination of the free volume in the SPBI membranes revealed that the hydronium ion transport is compatible with the Cohen-Turnbull model. Ultimately, by analyzing the radial/angular distribution functions and water clusters, a novel assessment of a potential proton conduction pathway completed the investigation. The findings imply that proton hopping via water cluster connections is feasible. [Display omitted] • MD simulation was performed to explore the proton conductivity of sulfonated PBIs. • Hydronium ion diffusion agrees with the Cohen-Turnbull model. • Radial/angular distribution functions are evaluated for proton conduction pathway. • Proton hopping through very well-interconnected water clusters is possible. [ABSTRACT FROM AUTHOR]

Abstract The formation of organic sediments, especially asphaltene in reservoirs, wells and equipment, has a harmful effect on the oil production economy, which reduces oil production and can block oil production facilities. In order to investigate the asphaltene aggregation and solubility, a series of molecular dynamics simulations in different conditions were performed on two famous asphaltene based model, of M1 and VI. VI asphaltene has two high aliphatic side chains, whereas M1 asphaltene has only two methyl groups on its sides. The simulation results show that the solubility parameter increases with increasing number of aromatic rings and decreasing the number of carbon atoms in the side chain. The aggregation of asphaltene molecules in toluene, heptane and isopropyl benzene solvents and also in the mixture of solvents has been investigated. The results show that the aggregation of M1 asphaltene in toluene and isopropyl benzene is lower than that of VI asphaltene. The mixture isopropyl benzene-heptane is appropriate solvent for both asphaltenes M1 and VI which represents less interaction between asphaltene molecules. The effect of six types of inhibitors on the aggregation of asphaltene was investigated. Based on the simulation results, the aggregation of asphaltene with the presence of DETPMP inhibitor significantly decreases due to the delay in the growth of crystals and by increasing the concentration of all used inhibitors, their inhibitory properties were decreased. Graphical abstract Image 1 Highlights • Aggregation of asphaltene was studied by molecular simulation. • Relationship solubility parameter and asphaltenes structure were studied. Solubility parameter of pure asphaltene and different solvents were calculated. • Effects of inhibitors on the aggregation of asphaltene were studied. [ABSTRACT FROM AUTHOR]

Abstract In this study, the effect of aqueous ions and sediment inhibitors on asphaltene aggregation was investigated. The effect of NaCl, MgCl 2 and CaCl 2 salts on three asphaltene models of M1, A1 and modified Yen and also the combined effect of two different inhibitors and these salts have been investigated by using molecular dynamics (MD). The results showed that due to presence of Na+, Mg2+ and Ca2+ cations, asphaltene aggregation has an ascending, descending, ascending trend, respectively and the amount of asphaltene aggregation in the A1 model due to having more electronegative atoms is higher than the other two. In the presence of diethylene triamine-penta methylene phosphonic acid (DETPMP) and poly-phosphino carboxylic acid (PPCA) inhibitors, the amount of sediment was reduced in all three models of asphaltene, but the asphaltene aggregation with the presence of DETPMP inhibitor significantly decreases due to the delay in the growth of crystals. Highlights • The effect of ions in water on asphaltene aggregation were studied by molecular dynamic simulation • The effect of side chain and the effect of electronegative atoms on asphaltene aggregation were investigated. • The effects of salts on the asphaltene aggregation were calculated. • The inhibitor effect on the aggregation of asphaltene in the presence of salts were studied. [ABSTRACT FROM AUTHOR]

Removal of cadmium ions from an aquatic solution was investigated by low-cost adsorbents and compared when modifying them by Fe-S nanoparticles. Nanocomposites were synthesized by a new experimental method under simple and inexpensive procedure by Fe-S nanoparticles, which possessed good characteristics of the surface area and magnetic property. These nanocomposite adsorbents removed cadmium at larger percentages than pure adsorbents. Iron filings had only a minor effect on the removal of cadmium, but when they were modified with Fe-S nanoparticles, the adsorption rate reached over 98.5%. Under operating conditions of pH 7, a concentration of 3 ppm, and a flow rate of 5 ml/min, the highest cadmium adsorption in water was caused by the iron nanocomposite. Display Omitted [ABSTRACT FROM AUTHOR]