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Inhibition of intestinal α‐glucosidase (αGS), a crucial enzyme in carbohydrate digestion, is an effective therapeutic approach for diabetes mellitus treatment. The C‐glycosylflavonoids (CGFs) are natural compounds with antioxidant, antidiabetic, and anti‐inflammatory activities. The present work seeks an alternative compound among CGFs that can control the blood glucose level by inhibiting αGS enzyme activity. Therefore, ten CGFs were selected and carried out the docking to αGS. The docking outcomes proposed that among selected CGFs, the orientin compound can successfully interact with the key residues of Asp215, Glu277, Asp352, Arg442, and Arg446. Of them, the orientin compound with docking energy of −6.11 Kcal/mol, was subsequently subjected to molecular dynamics simulation (MDs), and in vitro investigation. MDs results indicated that orientin formed a stable complex with αGS enzyme. We also performed molecular mechanics generalized Born and surface area (MM/GBSA) free energy calculation manner on all chosen CGFs along with miglitol as reference. The IC50 value of orientin for αGS inhibition with competitive mode was found to be 0.13 mg/ml. The results highlight that orientin can be considered as a possible compound in treating DM via αGS inhibition. However, further in vitro and in vivo analyses are required to confirm this claim. [ABSTRACT FROM AUTHOR]

Background: To resolve the impairments associated with spinal cord injury (SCI), such as decreased balance, patients have been recommended to undergo various therapeutic strategies, including the use of different physical exercise methods. The aim of this study was to evaluate the efficiency of using rebound therapy (exercise on a trampoline) on SCI individuals' static stability. Methods: Sixteen people with SCI (American Spinal Cord Association classification: A = 6, B = 6, C = 2, and D = 2) were randomly assigned to an experimental (rebound exercise) group or a control group. The rebound therapy exercise program, lasting 12 weeks, was performed by means of a modified trampoline. During the said period, the experimental group received rebound therapy exercise for 10 to 30 minutes 3 sessions a week. Standing stability parameters (ie, excursion, velocity, and path length of the center of pressure in mediolateral and anteroposterior plane) were assessed before and after the exercise intervention by Kistler force plate (50 × 60 cm). Data were analyzed by repeated measures analysis of variance. Results: Significant interactions were observed for all 6 dependent variables except excursion of the center of pressure in mediolateral and the path length of center of pressure in anteroposterior plane (P <.01). This means that the control group had no progress, whereas the experimental group made a significant improvement in terms of static stability. Conclusion: The results of this study confirmed that rebound therapy could reinforce the static stability of individuals with SCI during motionless standing. It suggests that rebound exercise is a useful sports rehabilitation method for patients with SCI and other wheelchair-bound individuals. [ABSTRACT FROM AUTHOR]

Flavonoid glycosides (FGs) appear to be good candidates for controlling blood glucose levels, so regular consumption of vegetables/fruits rich in FGs may prevent the consequences of type 2 diabetes (DM). Inhibition of digestive enzymes using natural FGs is a suitable dietary tool to regulate the hydrolysis of polysaccharides and overcome hyperglycemia. The aim of the current research is to find FGs that can effectively inhibit the digestive enzymes α-glucosidase (α-Gl) and α-amylase (α-Am). Accordingly, twenty-three FGs were selected and filtered through docking-based virtual screening. Based on the molecular docking and molecular dynamics (MD) simulation, among the 23 selected FGs, nicotiflorin and swertisin significantly inhibited α-Gl and α-Am, respectively. In vitro analysis revealed the inhibitory capacity of nicotiflorin on α-Gl was equal to IC50 at 0.148 mg/ml and the inhibitory activity of swertisin on α-Am was equal to IC50 at 1.894 mg/ml. It was found that nicotiflorin and swertisin act much like as a competitive inhibitor on α-Gl and α-Am, respectively. Furthermore, the fluorescence intensity of both enzymes decreased after interaction with two FGs. FT-IR and scanning electron microscopy (SEM) measurements suggested that the interactions could alter the conformation and microenvironment of the enzymes. Moreover, in vivo evaluation showed that the administration of nicotiflorin and swertisin can alleviate the blood glucose level of rats compared to the starch group (p < 0.05). The findings highlight that nicotiflorin and swertisin can be considered as possible inhibitors in treating diabetes mellitus via digestive enzymes inhibition. [ABSTRACT FROM AUTHOR]

The presence of faults in a system leads to a lower value for efficiency, accuracy and speed, and, in some cases, even a complete breakdown. Thus, early fault detection is a major factor in efficiency and productivity of the procedure. In recent decades, many research studies have been conducted on troubleshooting and secondary fault detection. The current work presents an efficient and novel observer design capable of stabilizing the residue and dynamic error for the nonlinear Lipschitz systems with faults as well as a troubleshooting analysis and determining the formation of secondary faults in defective systems. The observer is designed based on linearizing dynamic error considering uncertainty, disturbance, and defects by employing non-linear gain factors instead of using state transformation. The dynamic error and residue stabilization of a non-linear faulty system have been discussed as well as the likelihood of secondary fault generation. The results indicate that the observer is able to determine fault-emergence, fault-disappearance and secondary fault formation well and quite fast. [ABSTRACT FROM AUTHOR]

The electrokinetic energy conversion, electroviscous effect, and induced internal and external magnetic fields in a smart polyelectrolyte grafted "soft" nanopore with pH responsiveness are studied here using an efficient molecular theory approach. The analysis is based on writing the total free energy of the system, including the conformational entropy of the flexible, self-avoiding polymer chains and the translational entropy of the mobile species, the electrostatic interactions, and the free energy due to chemical equilibrium reactions. Then, the free energy is minimized, while satisfying the necessary constraints to find the equilibrium state of the system. The predictions of the model are shown to be in excellent agreement with analytical solutions derived for special cases. We discuss the effect of different influential environmental and polymer brush parameters in detail and show that the electrokinetic energy conversion efficiency is optimal at moderate pH values and low background salt concentrations. It is also shown that the electrokinetic energy conversion efficiency is a complex function depending on both the environmental and polymer brush properties. Notably, high slip coefficients or high polymer grafting densities do not necessarily lead to a high energy conversion efficiency. Magnetic field readouts allow to measure streaming currents through nanopores without the need of electrodes and may be utilized as a secondary electronic signature in nanopore sensing techniques. It is shown that in nanopores modified with polyelectrolyte brushes, the induced magnetic fields can be tens of times larger than those in solid-state nanopores having only surface charges. We show that by tuning the pH, background salt concentration, surface charge, and polyelectrolyte grafting density, the magnitude of the internal and external magnetic fields can be significantly changed and controlled in a wide range. [ABSTRACT FROM AUTHOR]

Human serum albumin (HSA) is an important carrier protein in plasma with various functions, and it is exposed to glycation. Alkaloids are diverse compounds that have showed different anti-glycation activities. The present study aimed to investigate the anti-glycation activity of thirty alkaloid compounds. First, the compounds were studied via Lipinski's rule; then, among thirty alkaloids, twenty-three were further designated for docking study, using AutoDock program. Three compounds which provided the minimum docking score were selected for further assays. Jatrorrhizine displayed potential activity to inhibit the HSA glycation. The stability of the jatrorrhizine-HSA complex was confirmed by molecular dynamics simulation (MDs). To approve the efficacy of this compound, future in vitro and in vivo studies are required. [ABSTRACT FROM AUTHOR]

Rice aroma profiles, consisting of different sorts of volatile organic compounds, go through complex alterations during storage period that affect its end-use quality. The aroma active compounds of rice are the key elements to determine its quality characteristics and freshness. This study evaluates the efficiency of electronic nose combined with modern biologically inspired unsupervised algorithms as a fast, real-time, and non-invasive technology for modelling rice aroma change during storage. The developed unsupervised algorithms could present successful results in clustering of the aroma change, and also could provide supplementary facilities for assessment of ageing in aromatic and non-aromatic rice samples. Self-organizing map neural network resulted in reliable grouping of the samples. The provided unified distance matrices were applied to interpret the pace of the aroma change. Fuzzy c-means was hybridized with differential evolution, and the fuzzifier parameter was applied for controlling of the samples' memberships to the storage clusters. The developed fuzzy clustering proposed more reasonable solutions when there were overlappings among the clusters. The automatic clustering developed by artificial bee colony algorithm proposed original grouping of the aromatic samples. For the non-aromatic rice, the structures obtained by the automatic approach agreed satisfactorily with the aroma change during ageing. The automatic clustering eliminated the need for the number of clusters as well as the descriptive labelled samples, and presented smarter performance. The electronic nose system combined with the developed unsupervised algorithms could be utilized as a reliable and rapid tool for analysis of rice aroma change. [Display omitted] • MOS based e-nose was applied for unsupervised modelling of rice aroma change. • Self-organizing map and the resulting U-matrix was applied for crisp clustering. • Differential evolution was hybridized with fuzzy c-means for fuzzy clustering. • Artificial bee colony was developed in automatic clustering framework. • E-nose combined with bio-inspired methods is fast and reliable in analyzing rice aroma. [ABSTRACT FROM AUTHOR]

• Accuracy of the force fields used for the simulation of CO 2 uptake is validated. • K sites in UTSA-16(Zn) have more tendency in CO 2 adsorption than Zn. • GCMC and MD simulations are utilized to develop novel MOFs for CO 2 capture. • Replacement of K cation with Li, Na, Rb, Be, Mg or Ca is investigatated. • Be and Mg are found to be most efficient cations due to their electronegativity. Metal Organic Frameworks (MOFs) have recently emerged as highly attractive materials, representing a significant advancement in the field of carbon dioxide (CO 2) capture. In this study, our objective is to validate existing experimental data and investigate the CO 2 adsorption properties of UTSA-16(Zn) by modifying its primary adsorption sites with alkali and alkaline earth metal cations. To achieve this, we employ Grand Canonical Monte Carlo (GCMC) and Molecular Dynamics (MD) simulations to explore the CO 2 adsorption uptake of the newly designed MOFs. Through MD simulations, we utilize the Radial Distribution Function (RDF) to identify the primary CO 2 adsorption sites within UTSA-16(Zn). Our results reveal that the potassium cation (K+) serves as the primary adsorption site. Building upon this information, we investigate the impact of replacing K+ with other metal cations such as Li+, Na+, Rb+, Be2+, Mg2+, and Ca2+ on the CO 2 adsorption capacity of the MOF. Our findings indicate that Be2+ and Mg2+ have a positive influence on the CO 2 uptake of the MOF due to their higher electronegativity compared to the other metal cations. Consequently, Be-UTSA-16(Zn) and Mg-UTSA-16(Zn) demonstrate superior performance in CO 2 adsorption compared to UTSA-16(Zn) under various inlet feed conditions. Notably, when pure CO 2 is supplied, the aforementioned new MOFs exhibit an increase in CO 2 adsorption capacity of 8.81 % and 5.37 %, respectively, in comparison to UTSA-16(Zn). These findings provide valuable insights into the CO 2 adsorption behavior of the newly designed MOFs and suggest potential strategies for designing efficient CO 2 capture MOFs. [ABSTRACT FROM AUTHOR]

The process of developing novel compounds/drugs is arduous, time-intensive, and financially burdensome, characterized by a notably low success rate and relatively high attrition rates. To alleviate these challenges, compound/drug repositioning strategies are employed to predict potential therapeutic effects for DrugBank-approved compounds across various diseases. In this study, we devised a computational and enzyme inhibitory mechanistic approach to identify promising compounds from the pool of DrugBank-approved substances targeting Diabetes Mellitus (DM). Molecular docking analyses were employed to validate the binding interaction patterns and conformations of the screened compounds within the active site of α-glucosidase. Notably, Asp352 and Glu277 participated in interactions within the α-glucosidase-ligand complexes, mediated by conventional hydrogen bonding and van der Waals forces, respectively. The stability of the docked complexes (α-glucosidase-compounds) was scrutinized through Molecular Dynamics (MD) simulations. Subsequent in vitro analyses assessed the therapeutic potential of the repositioned compounds against α-glucosidase. Kinetic studies revealed that "Forodesine" exhibited a lower IC 50 (0.24 ± 0.04 mM) compared to the control, and its inhibitory pattern corresponds to that of competitive inhibitors. In-depth in silico secondary structure content analysis detailed the interactions between Forodesine and α-glucosidase, unveiling significant alterations in enzyme conformation upon binding, impacting its catalytic activity. Overall, our findings underscore the potential of Forodesine as a promising candidate for DM treatment through α-glucosidase inhibition. Further validation through in vitro and in vivo studies is imperative to confirm the therapeutic benefits of Forodesine in conformational diseases such as DM. [ABSTRACT FROM AUTHOR]

The process of developing novel compounds/drugs is arduous, time-intensive, and financially burdensome, characterized by a notably low success rate and relatively high attrition rates. To alleviate these challenges, compound/drug repositioning strategies are employed to predict potential therapeutic effects for DrugBank-approved compounds across various diseases. In this study, we devised a computational and enzyme inhibitory mechanistic approach to identify promising compounds from the pool of DrugBank-approved substances targeting Diabetes Mellitus (DM). Molecular docking analyses were employed to validate the binding interaction patterns and conformations of the screened compounds within the active site of α-glucosidase. Notably, Asp352 and Glu277 participated in interactions within the α-glucosidase-ligand complexes, mediated by conventional hydrogen bonding and van der Waals forces, respectively. The stability of the docked complexes (α-glucosidase-compounds) was scrutinized through Molecular Dynamics (MD) simulations. Subsequent in vitro analyses assessed the therapeutic potential of the repositioned compounds against α-glucosidase. Kinetic studies revealed that "Forodesine" exhibited a lower IC 50 (0.24 ± 0.04 mM) compared to the control, and its inhibitory pattern corresponds to that of competitive inhibitors. In-depth in silico secondary structure content analysis detailed the interactions between Forodesine and α-glucosidase, unveiling significant alterations in enzyme conformation upon binding, impacting its catalytic activity. Overall, our findings underscore the potential of Forodesine as a promising candidate for DM treatment through α-glucosidase inhibition. Further validation through in vitro and in vivo studies is imperative to confirm the therapeutic benefits of Forodesine in conformational diseases such as DM. [ABSTRACT FROM AUTHOR]

To minimize uncertainty related to soil processes in extreme events, we need accurate soil hydraulic properties across the entire range of soil water content. However, conventional methods are time-consuming and limited to specific ranges. To estimate soil hydraulic properties throughout the entire range, we conducted inverse modeling using upward infiltration experiments, where a shortwave infrared imaging camera was used to obtain high-resolution soil moisture data in space and time. Because the commonly used van Genuchten–Mualemmodel is unsuitable for describing soil hydraulic properties for dry conditions, we tested an alternative model, the Peters-Durner-Iden model, which considers both capillary and film water. The inverse modeling successfully estimated soil hydraulic properties for sandy loam and loam soils, and we demonstrated that the Peters-Durner-Iden model captured soil moisture dynamics better than the van Genuchten–Mualemmodel for dry conditions. However, both models could not adequately describe the soil moisture data for the other soils. The direct observation of the water flow via shortwave infrared images clarified that the reduced success was because of violating the one-dimensional flow assumption for coarse-textured soils and the micro-heterogeneity in soil hydraulic properties for soils with fine silt and clay materials. • Soil hydraulic properties were estimated from shortwave infrared images. • Peters-Durner-Iden model captured soil moisture dynamics for dry conditions. • The framework was most suitable for sandy loam and loam soils. • Micro-heterogeneity of soils prevented the success of the framework. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global threat. Despite the production of various vaccines and different treatments, finding natural compounds to control COVID-19 is still a challenging task. Isoquinoline alkaloids are naturally occurring compounds known to have some potential antiviral activity. In this study, ten abundant isoquinoline alkaloids with antiviral activity were selected to analyze the preventive effect on COVID-19. A scrutinized evaluation based on Lipinski's rule showed that one out of ten compounds was toxic. Based on molecular docking analysis using Autodock software one of the best molecules with maximum negative binding energy was selected for further analysis. The Gromacs simulation analysis revealed that Coptisine has more action against active site Mpro of COVID-19. Overall, to make a rational design of various preventive analogues that inhibit the COVID-19, associated in vitro and in vivo analyses are needed to confirm this claim. [ABSTRACT FROM AUTHOR]

Given the prevalence of diabetes and the increasing number of diabetics, it is essential to find medicines to decrease the chronic complications of diabetes. Several studies have demonstrated that chronic hyperglycemia and its complications are directly related to protein glycation. Thus, identifying natural inhibitors to stop glycation of proteins may play a crucial role in managing the chronic complications of diabetes. Currently, various natural and synthetic compounds with anti-glycation attributes have been reported. The use of natural compounds in herbs (medicinal and non-medicinal) may be of particular importance due to fewer side effects and a wide range of therapeutic properties. Accordingly, this mini-review provides a list of common natural medicines and synthetic compounds with anti-glycation activity. As well, it provides brief information on the formation of advanced glycosylated end products (AGEs), their side effects, and glycation prevention mechanisms. [ABSTRACT FROM AUTHOR]

Inflammation is a natural protective response toward various simulators, including tissue damage or pathogens. The cyclooxygenase-2 (COX-2) is a very important protein in triggering pain and inflammation. Previous studies have claimed that Allium sativum offers a wide range of anti-inflammatory therapeutics for human consumption. Drug discovery is a complicated process, though in silico methods can make this procedure simpler and more cost-effective. At the current study, we performed the virtual screening of eight Allium sativum–derived compounds via molecular docking with COX-2 enzyme and confirmed the binding energy by docking score estimate followed by ADMET and drug-likeness investigation. The resulting highest-docking scored compound was exposed to molecular dynamics simulation (MDS) for evaluating stability of the docked enzyme-ligand complex and to gauge the oscillation and conformational alterations for the time of enzyme-ligand interaction. The factors of RMSD, RMSF, hydrogen bond interactions, and Rg after 100 ns of MDS proved the stability of alliin in the active site of COX-2 in comparison with celecoxib (CEL) as the control. Moreover, we investigated the binding affinity analysis of all compounds via MM/PBSA method. The results from this study suggest that alliin (a sulfuric compound) exhibits a higher binding affinity for the COX-2 enzyme compared to the other compounds and CEL. Alliin showed to be a possible anti-inflammatory therapeutic candidate for managing the inflammatory conditions. [ABSTRACT FROM AUTHOR]

A laboratory continuous high voltage electrostatic field thawing system was designed and constructed in accordance with standards for food machinery. A corona discharge in wire-plate electrodes was considered for the system and a stainless-steel sheet was utilized as conveyor belt. A corona flow was created by using high voltage of 15, 20, and 25 kV and electrode gaps of 6, 8, and 10 cm. To evaluate the system, frozen tylose MH4000 gel with a moisture content of 77% w.b. as a meat analog was thawed from -10 to 0°C. The thawing duration, which was mostly aimed at increasing the temperature of a control sample (no electrostatic field), considerably decreased when the gel was thawed in the presence of high voltage. High voltage and electrode gap showed a significant effect on both thawing duration and specific energy consumption (P˂0.0001). The thawing duration decreased significantly by decreasing the electrode gap and increasing the applied voltage. In terms of energy consumption, the best condition (minimum specific energy consumption of 10.33 kJ kg-1) was obtained for 15 kV, and an electrode gap of 10 cm. [ABSTRACT FROM AUTHOR]

During rice drying its starch exhibits a variety of thermal properties. It can be transformed from a rubbery state to a glassy state and vice versa due to temperature and moisture content gradients (MCGs) leading to the reduction in head rice yield. Intermittent drying is an effective drying method to overcome this issue. In this research, a novel mathematical model was developed for rice intermittent drying process considering the glass transition concept which has not been done before. In addition, the real 3D body-fitted geometry of the rice kernel was first utilized for simulation. To determine the required coefficients and validate the model, continuous and two-stage intermittent drying (2SID) experiments were performed. A correlation of 99% was found between the drying kinetics obtained from the experiments and those obtained from the model. Regarding the glass transition phenomenon, a quantitative S function was defined to express the local glassy-to-rubbery state at each time. The transitory temperature and moisture distributions inside the rice kernel were displayed and discussed at each stage of the 2SID. Further, the glass transition behavior of the rice kernels was investigated by using the S function's values. The glassy region extended by 28.8%, 3.3%, and 20.1% of the whole kernel rice at the first drying, tempering, and second drying stages, respectively. At the end of the 2SID, 45.6% of the entire kernel was located in the glassy region while the central layers were still located in the rubbery region. Overall, the developed model could be used to determine the optimal intermittent drying parameters for rice to improve its dehydration performance at a low cost. [Display omitted] • A novel mathematical model was developed to analyze multi-stage intermittent drying of rice. • Glassy-to-rubbery state kinetics of rice kernel was investigated during two-stage intermittent drying. • Transitory temperature and moisture distributions inside the rice kernel were obtained. • The simulated model could predict the optimal rice intermittent drying parameters. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a metabolic syndrome characterized by elevated blood glucose. The α-glucosidase enzyme is responsible for the hydrolysis of carbohydrates. This in silico study aimed to evaluate the inhibitory effects of the isolated compounds from Allium sativum L. on α-glucosidase. At first, sulfur and phenolic compounds of A. sativum L. were obtained from PubChem database, and α-glucosidase enzyme structure was obtained from Protein Data Bank. Toxicity class of compounds and the Lipinski parameter were predicted by Toxtree and Protox II and the Swiss ADME tools, respectively. Finally, the molecular interaction analysis between α-glucosidase and compounds from A. sativum L. was performed by AutoDock 4.2.6. Molecular interactions were investigated using Discovery Studio Visulizer and Ligplot 2.1 program. All of the selected sulfur and phenolic compounds from A. sativum L. followed the Lipinski's rules, had an acceptable binding energy, and lacked toxicity; therefore, they were appropriate candidates for α-glucosidase inhibition. Among these compounds, methionol and caffeic acid showed the lowest binding energy, and the highest inhibitory effect on α-glucosidase enzyme with − 3.9 and − 4.8 kcal/mol, respectively. These compounds also indicated the lower binding energy than the standard inhibitor (miglitol). Among the sulfur and phenolic compounds in A. sativum L., methionol and caffeic acid were predicted to be the powerful inhibitors, due to having more hydrogen binds and hydrophobic interactions with the active site of α-glucosidase. [ABSTRACT FROM AUTHOR]

Effect of dielectric barrier discharge (DBD) cold plasma on decontamination of strawberry and its quality characteristics was considered. Weight loss, color change, and firmness of the samples were investigated under low‐temperature storage condition. Plasma levels of 7% and 14% duty cycle were examined at exposure times of 5, 10, and 20 min. Destruction of microorganisms on treated samples surface was clearly observed by scanning electron microscopy images. Treatment duration of 20 min reduced total aerobic mesophilic bacteria and yeasts/molds 1.46 and 2.75 log CFU/g, respectively. Texture and color of the treated samples showed no significant difference compared to the control and their quality attributes indicated their superiority over the untreated one. The treated samples with 14% duty cycle DBD plasma for 20 min were even marketable at the end of the storage period. The cold plasma generated by DBD could, therefore, be utilized to prolong fruits shelf life. Practical applications: Cold plasma cleaning is a novel dry and nonthermal technology without the use of chemicals. The present study would be practically advantageous as it explains decontamination of strawberry as a part of many people's diet all over the world via dielectric barrier discharge (DBD) plasma. The plasma‐treated samples for 20 min were marketable after 12 days of storage. Hence, the nonthermal DBD plasma treatment is an effective way to prolong the shelf life of strawberry. [ABSTRACT FROM AUTHOR]

Diabetes mellitus is a metabolic syndrome characterized by elevated blood glucose. The α-glucosidase enzyme is responsible for the hydrolysis of carbohydrates. This in silico study aimed to evaluate the inhibitory effects of the isolated compounds from Allium sativum L. on α-glucosidase. At first, sulfur and phenolic compounds of A. sativum L. were obtained from PubChem database, and α-glucosidase enzyme structure was obtained from Protein Data Bank. Toxicity class of compounds and the Lipinski parameter were predicted by Toxtree and Protox II and the Swiss ADME tools, respectively. Finally, the molecular interaction analysis between α-glucosidase and compounds from A. sativum L. was performed by AutoDock 4.2.6. Molecular interactions were investigated using Discovery Studio Visulizer and Ligplot 2.1 program. All of the selected sulfur and phenolic compounds from A. sativum L. followed the Lipinski's rules, had an acceptable binding energy, and lacked toxicity; therefore, they were appropriate candidates for α-glucosidase inhibition. Among these compounds, methionol and caffeic acid showed the lowest binding energy, and the highest inhibitory effect on α-glucosidase enzyme with − 3.9 and − 4.8 kcal/mol, respectively. These compounds also indicated the lower binding energy than the standard inhibitor (miglitol). Among the sulfur and phenolic compounds in A. sativum L., methionol and caffeic acid were predicted to be the powerful inhibitors, due to having more hydrogen binds and hydrophobic interactions with the active site of α-glucosidase. [ABSTRACT FROM AUTHOR]

Understanding and reducing the uncertainties in the inversion of the first-order radiative transfer models at the L-band are important for the improved spaceborne retrievals of soil moisture (SM) and vegetation optical depth (VOD) over dense canopy. This article quantifies and compares the sensitivity of dual-channel inversion of the two-stream (2S) and $\tau $ – $\omega $ models and proposes a new inversion approach for simultaneous retrievals of SM, VOD, and vegetation-scattering albedo ($\omega $) from a single satellite overpass. In particular, the inversion algorithm incorporates the information of the nearby spatial observations, assuming that the values of VOD and $\omega $ remain locally invariant, and constrains its solutions to high-resolution a priori physical/climatological knowledge of the retrieval variables. The results demonstrate that the uncertainty in the inversion of 2S model is slightly higher than the $\tau $ – $\omega $ model under noisy observations and remains homoscedastic for SM and $\omega $ , while grows heteroscedastically for higher VOD values due to the shape of the cost function. The results are validated using the SMAP data, the dense Mesonet SM network, the in situ measurements from the International SM Network (ISMN), and the derived VOD from the Moderate Resolution Imaging Spectroradiometer (MODIS)-normalized difference vegetation index (NDVI) over the state of Oklahoma in the United States. It is shown that the new approach can recover simultaneously high-resolution features of SM, VOD, and $\omega $ only from a single Soil Moisture Active Passive (SMAP) overpass, where the unbiased root-mean-squared error (ubRMSE) of SM and VOD is reduced by 30% and 70%, respectively, when compared with an unconstrained time-windowed inversion approach. [ABSTRACT FROM AUTHOR]

• The b-N-TiO 2 photocatalyst was synthesized as a highly active and recyclable catalyst. • The narrowed bandgap of 2 eV extends the photoresponse to visible light region. • The synergy of N, Ti3+ codoping and oxygen vacancies promoted the visible absorption. • The degradation efficiency of CIP over b-N-TiO 2 was two times more than N-Ti0 2. • The b-N-TiO 2 /LED process was efficient in toxicity reduction of CIP. In this work, the photocatalytic degradation of ciprofloxacin (CIP) by black Ti3+/N-TiO 2 under visible LED light irradiation (b-N-TiO 2 /LED) was studied for the first time. Characterization of the prepared photocatalyst was performed by XRD, UV–Vis DRS, FE-SEM, EDS, HRTEM, and BET techniques. The b-N-TiO 2 nanoparticles with high surface area of near 100 m2 g−1 and narrow band gap of 2.0 eV, exhibited a remarkable photocatalytic performance on the degradation (100 %) and mineralization (82 %) of CIP under visible LED light irradiation. The maximum degradation was found at reaction time = 70 min, initial CIP concentration = 0.5 mg L−1, pH = 6.7, and catalyst dosage = 0.43 g L−1. Based on the results, both the hole (h+) and hydroxyl radical (OH) played a major role than the superoxide radical (O 2 −) in CIP degradation. Although common coexisting anions in water had a slight negative effect on CIP degradation; humic acid (HA), especially in higher amounts, showed a considerable inhibitory effect on degradation process. Besides, the intermediates of CIP degradation were ultimately transformed into simple compounds. Accordingly, toxicity assessments revealed that the treatment of CIP solution by b-N-TiO 2 /LED process remarkably resulted in diminished toxicity compared to the untreated controls. The energy utilized in this study was far less than that used in other studies. Moreover, we found that b-N-TiO 2 had desirable stability and can be reused for more than five runs of experiments. Collectively, based on our findings, the b-N-TiO 2 /LED process is a promising, low cost and feasible candidate can be used for degradation and mineralization of antibiotics like CIP in real water samples. [ABSTRACT FROM AUTHOR]

The membrane technology has received considerable attention for olefin/paraffin separation in recent years, owing to its attractive energy efficiency. In this study, reduced graphene oxide (rGO) is prepared via hydrothermal treatment of graphene oxide. The prepared rGO is characterized and then incorporated into polysulfone (PSF) to fabricate mixed‐matrix membranes (MMMs). The fabricated membranes are characterized using Fourier transform infrared spectrometry, field emission scanning electron microscopy, and X‐ray powder diffraction. The gas transport properties of the MMMs are evaluated for ethylene/ethane and propylene/propane gas pairs at 2 bar and 30∘C. Permeation tests indicate that the PSF membrane embedded with 1.0 wt% of the rGO nanosheets has 143% and 193% higher C2H4 and C3H6 permeabilities, respectively, its C3H6/C3H8 selectivity is 18% higher, but its C2H4/C2H6 selectivity is 23% lower, compared to those of the pristine PSF membrane. The gas permeability enhancement is attributed to improved gas diffusion and solubility coefficients. These results indicate the potential of rGO nanosheets for the enhancement of olefin permeabilities without significant drops in olefin/paraffin selectivities. [ABSTRACT FROM AUTHOR]

In-depth knowledge about the global patterns and dynamics of land surface net water flux (NWF) is essential for quantification of depletion and recharge of groundwater resources. Net water flux cannot be directly measured, and its estimates as a residual of individual surface flux components often suffer from mass conservation errors due to accumulated systematic biases of individual fluxes. Here, for the first time, we provide direct estimates of global NWF based on near-surface satellite soil moisture retrievals from the Soil Moisture Ocean Salinity (SMOS) and Soil Moisture Active Passive (SMAP) satellites. We apply a recently developed analytical model derived via inversion of the linearized Richards' equation. The model is parsimonious, yet yields unbiased estimates of long-term cumulative NWF that is generally well correlated with the terrestrial water storage anomaly from the Gravity Recovery and Climate Experiment (GRACE) satellite. In addition, in conjunction with precipitation and evapotranspiration retrievals, the resultant NWF estimates provide a new means for retrieving global infiltration and runoff from satellite observations. However, the efficacy of the proposed approach over densely vegetated regions is questionable, due to the uncertainty of the satellite soil moisture retrievals and the lack of explicit parameterization of transpiration by deeply rooted plants in the proposed model. Future research is needed to advance this modeling paradigm to explicitly account for plant transpiration. [ABSTRACT FROM AUTHOR]

The separations of ethylene/ethane and propylene/propane using polysulfone‐silica nanocomposite membranes were studied. Silica nanoparticles were prepared via sol‐gel method and the membranes by phase inversion. Characterization by Fourier transform spectroscopy and scanning electron microscopy indicated a good distribution of silica nanoparticles in the polymer matrix and also a good compatibility between the two phases. The performances of the prepared membranes in ethylene‐ethane and propylene‐propane separation were evaluated. The results showed the increments in gas permeability and selectivity by silica. Higher silica contents increased the solubility coefficient and reduced the diffusion coefficient of gases. The plasticization pressure of polysulfone was increased by incorporating the silica nanoparticles in polymer. [ABSTRACT FROM AUTHOR]

• Dynamic modeling of pigging process by improved model of PIG in pipe conveying fluid. • Theoretical and experimental study of PIG parameters effect on dynamic of pipeline. • Extraction of pipeline modal parameters through internal flow are not often possible. • Pigging process can be used as a tool to extract the modal parameters of pipeline. In this paper, the effects of PIG (Pipeline Inspection Gauge) parameters on dynamic response of a simply supported Above-Ground pipeline are investigated during pigging operation. The approach is based on finite element modeling verified by the experimental modal analysis (EMA). In the author's previous study, the governing equations of motion for system (Pipe, PIG as a moving vibrational sub-system, and conveyed fluid) were obtained using Hamilton's principle. In the present study, extracted equation are developed based on PIGs with different geometric parameters. The modal parameters of the pipeline system are calculated in the intermittent passage of PIGs along the pipe under different flow rates and their variations are extracted. Theoretical and experimental studies are performed to determine the effect various PIG parameters have on dynamic behavior of pipeline system. Changes in the system natural frequencies due to the speed and position of PIG in the pipe are also investigated. Moreover, displacement analysis for the mid-span of the considered pipe during the pigging operation is conducted using suggested theoretical model. Both numerical and experimental results show the substantial effects of PIG physical parameters, especially disc number and material, on dynamic behavior of the pipe system. [ABSTRACT FROM AUTHOR]

Although carbon nanotubes possess unique characteristics to be used for separation purposes, one of the most challenging problems affecting the preparation of carbon nanotubes-incorporated-mixed matrix membranes has been ascribed to Van der Waals interactions among carbon nanotubes walls, which hinder the pristine nanotubes' ability to make good interfacial interactions within the polymer matrix. To overcome this challenge, herein, poly (styrene sulfonic acid)-grafted- multi-walled carbon nanotubes were prepared via in-situ radical polymerisation and then incorporated into poly (vinyl alcohol), resulting in enhanced pervaporation performance of poly (vinyl alcohol) membranes. The observed results indicated that poly (styrene sulfonic acid)-modified carbon nanotubes could effectively vanquish the Van der Waals forces between nanotube walls. In general, our experiments revealed that the attachment of a bulky polymer containing hydrophilic sulfonic groups could improve the pervaporation performance of a poly (vinyl alcohol) membrane. [ABSTRACT FROM AUTHOR]

Biflavonoids (BFs) are a group of polyphenols that have a unique biochemical structure. One of the key biomedical mechanisms that BFs can have high potential in managing Diabetes mellitus (DM) is α-glucosidase inhibition. Normally, elevated blood glucose levels are caused by high absorption of glucose in the epithelium of the small intestine. Since α-glucosidase helps increase the absorption of glucose in the small intestine in the final stage of glycan catabolism, inhibition of this essential biochemical process in diabetic patients can be considered a suitable approach in the treatment of this disease. The interaction between the BFs and α-glucosidase are still not clear, and need to be deeply investigated. Herein, the aim is to identify BFs with strong α-glucosidase inhibitory activity. Using docking-based virtual screening approach, the potential binding affinity of 18 selected BFs to α-glucosidase was evaluated. The dynamic activity and stability of α-glucosidase-BFs complexes were then measured by molecular dynamics simulation (MDs). "Strychnobiflavone" showed the best score in α-glucosidase inhibition. Arg315 and Phe303 involved in the interactions of α-glucosidase-strychnobiflavone complex through cation-π and π-π stacking, respectively. Based on in vitro kinetic studies, it was determined that the type of inhibition of "strychnobiflavone" corresponds to the pattern of mixed inhibitors. Furthermore, details of the interactions between strychnobiflavone and α-glucosidase were performed by in silico secondary structure content analysis. The findings showed when "strychnobifone" binds to the enzyme, significant alterations occur in the enzyme conformation affecting its catalytic activity. In general, the findings highlighted the potential of "strychnobiflavone" as a promising candidate for the treatment of diabetes mellitus through α-glucosidase inhibition. Further in vitro and in vivo studies have to confirm the therapeutic benefits of "strychnobiflavone" in conformational diseases such as diabetes mellitus. [ABSTRACT FROM AUTHOR]

• A new laboratory method for estimating soil water retention is introduced. • The method only requires soil water content-dependent SWIR reflectance data. • Validation for 21 vastly different soils indicates a good performance. The soil water retention curve (SWRC) is an essential soil property that relates soil water content and matric potential. It plays a crucial role in soil water dynamics and the understanding of various hydrological phenomena at the land surface, including infiltration, runoff, evaporation, and energy exchange processes. In recent years, proximal sensing methods have shown great potential for retrieving this challenging-to-measure property from spectral reflectance. However, a physically-based approach is still lacking as current methods rely on empirical data-driven algorithms. Here we propose a novel physics-based laboratory method that, for the first time, enables direct estimation of the entire SWRC from saturated to dry using soil water content/reflectance data pairs within the shortwave infrared domain. The main hypothesis underlying the new method is that soil optical properties not only vary with soil water content but also with the pore scale distribution of capillary and adsorbed soil water. For evaluation, retrieved soil water retention curves of 21 soils that vastly differ in physical and hydraulic properties were compared to direct measurements. The results suggest that the new method is a rapid and efficient alternative to established laboratory measurement methods. [ABSTRACT FROM AUTHOR]

Soil moisture (SM) is a key hydrologic state variable that is of significant importance for numerous Earth and environmental science applications that directly impact the global environment and human society. Potential applications include, but are not limited to, forecasting of weather and climate variability; prediction and monitoring of drought conditions; management and allocation of water resources; agricultural plant production and alleviation of famine; prevention of natural disasters such as wild fires, landslides, floods, and dust storms; or monitoring of ecosystem response to climate change. Because of the importance and wide‐ranging applicability of highly variable spatial and temporal SM information that links the water, energy, and carbon cycles, significant efforts and resources have been devoted in recent years to advance SM measurement and monitoring capabilities from the point to the global scales. This review encompasses recent advances and the state‐of‐the‐art of ground, proximal, and novel SM remote sensing techniques at various spatial and temporal scales and identifies critical future research needs and directions to further advance and optimize technology, analysis and retrieval methods, and the application of SM information to improve the understanding of critical zone moisture dynamics. Despite the impressive progress over the last decade, there are still many opportunities and needs to, for example, improve SM retrieval from remotely sensed optical, thermal, and microwave data and opportunities for novel applications of SM information for water resources management, sustainable environmental development, and food security. Key Points: Recent soil moisture measurement and monitoring techniques and estimation models from the point to the global scales and their limitations are presentedThe importance and application of soil moisture information for various Earth and environmental sciences disciplines such as forecasting weather and climate variability, modeling hydrological processes, and predicting and monitoring extreme events and their impacts on the environment and human society are presented [ABSTRACT FROM AUTHOR]

Abstract The aroma change of aromatic and non-aromatic rice was traced during storage using electronic nose (E-nose). Various steady-state and transient features were derived from the adsorption and desorption phases of the E-nose responses to characterize the ageing process and classify the storage durations. Principal component analysis was utilized to analyse the ageing in terms of seven classes related to the storage duration of 6 months. The aromatic samples followed a specific pathway in its timeline with separately distinctive grouping, revealing the reduction of ageing indices. The aromatic rice underwent crucial changes in its volatile compounds, mainly in the early stages of storage. While, confused grouping of the non-aromatic rice proved its stability due to less diverse range of the aroma compounds. Several artificial neural networks, namely back propagation (BP), radial basis function (RBF), and learning vector quantization (LVQ) were used to classify the storage durations. For the aromatic samples, full classification was achieved by using all the networks. For the non-aromatic rice, the developed RBF and LVQ networks represented full classification by using the features of rise time and polynomial curve fitting parameters. It is concluded that the E-nose system along with the developing methods could be utilized to control the rice ageing. Graphical abstract Image 1 Highlights • E-nose was utilized to trace the aroma change of rice varieties during their ageing. • Ageing characteristics were interpretable by the nature of the extracted features. • Full classification of the six months storage duration was achieved by the used ANNs. • E-nose combined with developing methods is recommended to control the ageing. [ABSTRACT FROM AUTHOR]

Abstract A series of poly(urethane-urea) (PUU) membranes based on contributing hard segments in gas separation were prepared using two novel bulky chain extenders, polytetramethylene-glycol, isophorone and hexamethylene-diisocyanate. The chain extenders were synthesized by cyanuric chloride, aniline/naphthylamine and hydrazine. According to FTIR, AFM and DSC, bulkier PUU membranes showed more phase separation and lower glass transition temperature consistent with higher fractional free volume, which were correlated with single (CO 2 , CH 4 , O 2 and N 2) and mixed (CO 2 :N 2 and CO 2 :CH 4) gas permeation results. The main findings indicate these polyurethanes serve efficiently designed molecular structures favoring bulky hard segments contribution in gas separation. The bulky PUU membranes afford simultaneous increased permeability and selectivity, while maintaining high tensile properties. Enhanced O 2 /N 2 diffusivity selectivity by bulkier PUU and CO 2 sorption/desorption study by Ellipsometry confirmed hard segments' association, too. The bulkiest membrane provided 126% and 54% improvement for single CO 2 permeability and CO 2 /N 2 selectivity compared to linear one. Graphical abstract fx1 Highlights • A series of PUU membranes were prepared based on two novel bulky chain extenders. • The synthesized chain extenders and PUUs characterized completely. • The gas separation, physical and mechanical properties of bulky PUUs were evaluated. • Association of hard segments and enhancement on gas separation properties was shown. • High gas permeability/selectivity and high mechanical strength afforded in bulky PUUs. [ABSTRACT FROM AUTHOR]

Highlights • An analytical model for estimation of land surface net water flux is introduced. • Near-surface soil moisture is the only input variable. • The model can be parameterized without the need for calibration with measured data. Abstract The accurate determination of land surface water fluxes at various spatiotemporal scales remains a challenge in hydrological sciences. It is intuitive that land surface net water flux (i.e., infiltration minus evapotranspiration) directly affects near-surface soil moisture. However, there exists no hydrological model suitable to calculate net water flux based on measured near-surface soil moisture data. This is a consequence of the mathematical structure of existing models that use 'boundary conditions' to determine 'internal conditions', whereas what is needed is a model amenable to use near-surface soil moisture data (an internal condition) to determine the surface water flux (a boundary condition). To pursue the idea of utilizing remotely-sensed or in situ (i.e., sensor networks) near surface soil moisture data for estimation of net water flux, we derived an analytical model via inversion of Warrick's 1975 analytical solution to the linearized Richards' equation for arbitrary time-varying surface flux boundary conditions. The applicability of the new analytical solution was evaluated based on actual water flux observations as well as HYDRUS-1D simulations for four vastly different sites in Arizona, California, Idaho, and Indiana. Our results demonstrate that the proposed model reasonably captures net water flux variations in natural settings, including layered and vegetated soils, especially at larger time scales (e.g., monthly). While the model works for a wide range of climatic conditions, the prediction accuracy is somewhat lower for extreme dry or wet conditions. A major advantage of the new model is that it does not require calibration, which provides an unprecedented opportunity for large scale estimation of land surface net water flux using remotely sensed near-surface soil moisture observations. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • New mixed matrix membranes (MMMs) were fabricated. • Dispersion of nanoparticles was controlled by adjusting nanoparticles chemistry. • The gas-separation performance of the MMMs is higher than that of the pristine membrane. Abstract This paper presents a study on control of nanoparticles dispersion in the hard and soft segments of a polyurethane (PU) membrane, via adjusting surface groups of the nanoparticles. The dispersion control allows for tailoring physical and transport properties of the membrane. PU-based mixed-matrix membranes (MMMs) embedded with cyanuric chloride and its derivatives, melamine, and 2,4,6-trihydazino-1,3,5-triazine (THDT) nanoparticles, are prepared. The MMMs are characterized using FTIR, XRD, TGA, DSC, and SEM analyses, and tensile strength tests. Peak assignment of the bonded carbonyl, crystallinity change, mechanical properties of the membranes, possible hydrogen-bonding of the PU backbone and the nanoparticles, and permeation tests indicate that cyanuric chloride nanoparticles are dispersed in the hard segments, whereas melamine and the THDT nanoparticles are distributed in the soft domains. As the cyanuric chloride nanoparticle concentration of the MMMs increases, the gas permeabilities and O 2 /N 2 , CO 2 /CH 4 and CO 2 /N 2 selectivities of the membranes increase. In the case of THDT and melamine, as the filler loading increases, the permeabilities of the gases decrease, whereas O 2 /N 2 , CO 2 /CH 4 and CO 2 /N 2 selectivities increase. A 10 wt% incorporation of THDT into the PU increases CO 2 /N 2 and CO 2 /CH 4 selectivities by 92% and 75%, respectively. These results point to the potential of cyanuric chloride nanoparticles for simultaneous improvement of gas permeability and selectivity, and the potential of melamine and THDT nanoparticles for preparation of highly selective nanocomposite membranes for CO 2 removal. [ABSTRACT FROM AUTHOR]

Abstract: In this study, the effects of silica nanoparticles on the permeability of pure CO2, O2, and N2 gases in cellulose acetate (CA) membrane have been studied. Silica particles were prepared via the sol–gel method through the hydrolysis of tetraethyl orthosilicate (TEOS). CA and CA/silica nanocomposite membranes were prepared by thermal phase inversion method. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and Fourier transfer infrared (FTIR) analyses were employed to characterize the CA and CA/silica nanocomposite membranes. Gas permeation experiments showed an increase in the permeability of CO2 from 6.32 to 7.3 barrer and a reduction in the permeability of N2 from 0.18 to 0.09 barrer with the increment in silica content of the prepared composite membranes up to 20 wt%. Therefore, CO2/N2 selectivity of the nanocomposite membranes increased by increasing the silica content in the polymer matrix from 30 to 80 for 20 wt% load of silica. [ABSTRACT FROM AUTHOR]

The OPtical TRApezoid Model (OPTRAM) has recently been proposed for estimation of soil moisture using only optical remote sensing data. The model relies on a physical linear relationship between the soil moisture content and shortwave infrared transformed reflectance (STR) and can be parameterized universally (i.e., a single calibration for a given area) based on the pixel distribution within the STR-Normalized Difference Vegetation Index (NDVI) trapezoidal space. The main motivation for this study was to evaluate how the universal parameterization of OPTRAM works for long periods of time (e.g., several decades). This is especially relevant for uncovering the soil moisture and agricultural drought history in response to climate change in different regions. In this study, MODIS satellite observations from 2001 to 2017 were acquired and used for the analysis. Cosmic-ray neutron (CRN) soil moisture data, collected with the COsmic-ray Soil Moisture Observing System (COSMOS) at five different sites in the U.S. covering diverse climates, soil types, and land covers, were applied for evaluation of the MODIS-OPTRAM-based soil moisture estimates. The OPTRAM soil moisture estimates were further compared to the Soil Moisture Active and Passive (SMAP) (L-band), the Soil Moisture Ocean Salinity (SMOS) (L-band), and the Advanced AScatterometer (ASCAT) (C-band) soil moisture retrievals. OPTRAM soil moisture data were also analyzed for potential monitoring of agricultural drought through comparison of the OPTRAM-based Soil Water Deficit Index (OPTRAM-SWDI) with the widely-applied Crop Moisture Index (CMI). Evaluation results indicate that OPTRAM-based soil moisture estimates provide overall unbiased RMSE and R between 0.050 and 0.085 cm 3  cm −3 and 0.10 to 0.70, respectively, for all investigated sites. The performance of OPTRAM is comparable with the ASCAT retrievals, but slightly less accurate than SMAP and SMOS. OPTRAM and the three microvave satellites captured CRN soil moisture temporal dynamics very well for all five investigated sites. A close agreement was observed between the OPTRAM-SWDI and CMI drought indices for most selected sites. In conclusion, OPTRAM can estimate temporal soil moisture dynamics with reasonable accuracy for a range of climatic conditions (semi-arid to humid), soil types, and land covers, and can potentially be applied for agricultural drought monitoring. [ABSTRACT FROM AUTHOR]

It has been widely known that for complicated beam-like structures with various types of attachments and/or discontinuities analytical techniques are not always applicable. In this paper, a very efficient numerical method based on the Tau method is proposed to tackle the mentioned problem. A general form of the linear vibrational eigen-equation, based on the Euler–Bernoulli bending theory, together with its boundary conditions and continuity equations is considered. The problem is then formulated using a segmented form of the operational Tau method which is called the segmented operational Tau method. To investigate the reliability and accuracy of the proposed method some vibrational problems are solved and compared with the analytical solutions providing the exact frequencies and mode shapes. For a complicated case of a non-uniform beam with various types of attachments, since there was no analytical solution, results are validated with the finite element method. This paper has provided a platform for solving free vibrational problems of many complicated constrained systems through a very simple, highly accurate technique. [ABSTRACT FROM AUTHOR]

Experimental evidence points to an intimate link between soil reflectance, R , and particle/aggregate diameter, D . Based on this strong correlation, various statistical methods for remote and proximal sensing of soil texture and hydraulic properties have been developed. In this paper, we derive a more fundamental and physically-based analytical radiative transfer model that yields a closed-form functional R ( D ) relationship for dry soils. Despite several simplifying assumptions, the proposed model shows good agreement with measured spectral reflectance (350–2500 nm) data of six soils covering a broad range of textures, colors, and mineralogies. The proposed S-shaped R ( D ) function resembles cumulative particle and pore size distributions as well as the soil water characteristic function. These analogies may potentially lead to new avenues for developing novel physical models for extracting important soil properties from remotely sensed reflectance data. [ABSTRACT FROM AUTHOR]

ABSTRACT: The effect of zeolite 3A, 4A, and ZSM‐5 on the gas separation performance of polyurethane (PU)–zeolite mixed matrix membranes (MMMs) has been investigated in this study. Permeation of pure CO2, CH4, N2, and O2 gases through PU–zeolite MMMs with zeolite content of 6, 12, 18, and 24 wt% was studied. The prepared hybrid membranes were characterized using Fourier transform infrared spectroscopy and scanning electron microscope. Membrane characterization confirmed the homogeneous distribution of zeolite particles at low zeolite loadings in the prepared membranes. The obtained results confirmed a significant enhancement in the permeability of all gases and the CO2/N2, CO2/CH4, and O2/N2 selectivities by increasing the content of zeolite particles in PU–zeolite MMMs. The PU–zeolite 4A with 12 wt% zeolite loading showed the best performance in terms of gas permeability and selectivity for CO2/N2, CO2/CH4 and O2/N2 gas pairs. [ABSTRACT FROM AUTHOR]

In this study, multi-stage intermittent drying (MSID) of rough rice is considered based on stress cracking index (SCI), tempering index (TI), and total drying/tempering duration for Hashemi and Koohsar varieties experimentally and theoretically. The samples were dried at 60°C for 20, 40, and 60 min and tempered at 60°C for 40, 80, 120, 160, 200, and 240 min after each drying stage. Afterward, the completion of the tempering process was assessed using the TI along with analysis of moisture content kinetics by a simplified drying model. For both varieties, the SCI decreased significantly until continuing the tempering operation to certain durations and increased for longer drying durations in each drying stage. Considering the SCI and the total drying/tempering duration, the tempering durations of 200 and 160 min after 40 min drying in each stage were determined as the best performed conditions for MSID of Hashemi and Koohsar varieties, respectively. The results achieved by the TI were in conformity with those obtained by the mathematical model. It was concluded that the TI and simulation of surface moisture content on a kernel could be applied for estimating the time required for supplementation of the tempering process to eliminate moisture content gradients created inside the kernels during the drying process. [ABSTRACT FROM PUBLISHER]

Semi-analytical solutions are obtained for the electrical potential, electroosmotic velocity, ionic conductance, and surface physicochemical properties associated with long pH-regulated nanochannels of arbitrary but constant cross-sectional area. The effects of electric double layer overlap, multiple ionic species, and surface association/dissociation reactions are all taken into account, assuming low surface potentials. The method of analysis includes series solutions which the pertinent coefficients are obtained by applying the wall boundary conditions using either of the least-squares or point matching techniques. Although the procedure is general enough to be applied to almost any arbitrary cross section, nine nanogeometries including polygonal, trapezoidal, double-trapezoidal, rectangular, elliptical, semi-elliptical, isosceles triangular, rhombic, and isotropically etched profiles are selected for presentation. For the special case of an elliptic cross section, full analytical solutions are also obtained utilizing the Mathieu functions. We show that the geometrical configuration plays a key role in determination of the ionic conductance, surface charge density, electrical potential and velocity fields, and proton enhancement. In this respect, the net electric charge and convective ionic conductance are higher for channels of larger perimeter to area ratio, whereas the opposite is true for the average surface charge density and mean velocity; the geometry impact on the two latest ones, however, vanishes if the background salt concentration is high enough. Moreover, we demonstrate that considering a constant surface potential equal to the average charge-regulated potential provides sufficiently accurate results for smooth geometries such as an ellipse at medium-high aspect ratios but leads to significant errors for geometries having narrow corners such as a triangle. [ABSTRACT FROM AUTHOR]

In this study the non-linear system identification (NSI) and parameter estimation of a model of a cantilever beam with non-linear stiffness attached to its free end are investigated. For this purpose, the impulse response of the beam model, in the presence of added measurement noise, is obtained by solving the weak form of the governing equation of motion via Rayleigh-Ritz method. The non-linear interaction model (NIM) including a set of intrinsic modal oscillators (IMOs) is constructed based on intrinsic mode functions (IMFs), which are derived by applying empirical mode decomposition (EMD) on the noise-contaminated response signals. For reducing the effect of noise and increasing the accuracy of extracted IMFs, the EMD-based noise reduction is employed, followed by the modification of the IMF amplitudes by introducing a 'beta-factor' criterion. The changes in the amplitudes of the forcing functions associated with IMOs are used to extract features to estimate the non-linear parameter of the system. To this end, an artificial neural network has been trained to establish the non-linear relationship between the non-linearity of the system and the forcing functions of IMOs. [ABSTRACT FROM AUTHOR]

Poly (ethylene glycol) (PEG)-based polyurethane (PU) membranes are attractive materials for CO 2 separation from various sources such as flue gas and syngas. However, the strong tendency of PEG chains to crystallize leads to reduced permeability of the membrane. Here, we developed new types of PU chemistries with high PEG content and reduced crystallinity. A series of PUs were synthesized based on mixtures of PEG and poly (propylene glycol) (PPG), and various PEG-PPG triblock copolymers (PEG-b-PPG). The presence of PEG-b-PPG triblock copolymers combines the high selectivity of PEG while the PPG pendant methyl group hinders local crystallization. The resulting membranes showed CO 2 permeability of 144 barrer and high CO 2 /N 2 and CO 2 /H 2 selectivities up to 54 and 8.3, respectively. Due to the absence of the crystalline soft phase, synthesized PUs with PEG-b-PPG triblock copolymers exhibit higher chain flexibility which is reflected by a decrease in the glass transition temperature of the soft segments. In contrast, the mixture of PEG and PPG showed minimal effects on the crystallinity of PEG domains. This resulted in lower membrane gas separation performance where CO 2 permeability and CO 2 /H 2 selectivity decreased to 68 barrer and 4.9, respectively. [ABSTRACT FROM AUTHOR]

A century of research focused primarily on agricultural soils has largely ignored stony soils, which dominate some forests and are poorly understood in terms of the stone influence on soil hydraulic properties. Motivated by this knowledge gap, we quantified the influence of soil-containing stone fragments on bulk soil hydraulic properties by determining the water retention curve (WRC) of soil, stone and stone-soil mixtures with varied volumetric stone content. The measured WRC for seven different stone types based on their composition showed maximum and minimum saturated water contents of 0.55 m 3 m −3 in pumice and 0.025 m 3 m −3 in fine sandstone, respectively. The stony soil water retention function was measured using the simplified evaporation method. Contrasting scenarios were studied considering a broad range of stone inclusions; ( i ) negligibly porous, ( ii ) significantly porous but less porous than the background soil, ( iii ) more porous than the background soil. An averaging scheme to describe the WRC of stony soil was proposed based on the individual WRC of the background and stone inclusion which was in good agreement with the experimental data. The HYDRUS-3D model was also employed to simulate the evaporation experiment used for the WRC measurements. The model simulations supported the basic assumptions of the proposed averaging scheme. [ABSTRACT FROM AUTHOR]

Interfacial properties play an important role in determining characteristics and performance of composite materials, especially in membrane gas separation applications. Formation of any undesirable defect at polymer-particle interface can directly influence on membrane permeability and selectivity in addition to unwanted effects on the other mechanical/physical properties. For achieving a quick insight about the role and nature of interfacial morphologies in mixed matrix membranes (MMMs) and their effects on gas transport properties, a new technique mainly in terms of mathematical modeling was developed. Based on the proposed approach, although ideal models often failed in predicting MMMs performance, these models can provide guidelines for discernment of the types of formed interfacial morphology, like current methods in characterization. [ABSTRACT FROM AUTHOR]

This study involves the preparation and characterization of polyurethane (PU) and polyurethane/poly(ether-block-amide) (PU/PEBA) blend membranes for gas separation. Polyurethane was synthesized by two-step polymerization based on isophorone diisocyanate (IPDI), polytetramethylene glycol (PTMG2000), 1,4-butanediamine (BDA) and 1,4-butanediol (BDO) in mole ratios of 3:1:2. Two kinds of PEBA, MV3000 and MH1657, were chosen to prepare PU/PEBA blend membranes. The effects of the blend composition on the permeability of N 2 , O 2 , CO 2 and CH 4 were investigated. All membranes were prepared by thermal phase inversion. Physical properties of synthesized polyurethane and prepared blend membranes were investigated by FT-IR, XRD and SEM analyses. FT-IR results indicate that phase separation of hard and soft segments decreased as the amount of PEBA in blend membranes increased. XRD results demonstrate that crystallinity rose by increasing the amount of PEBA in the blends. According to the SEM micrographs of the prepared samples, PU/PEBA blend membranes are miscible systems. The results of gas permeation experiments demonstrate that by increasing the amount of PEBA in PU/PEBA blend membranes, the permeability of all gases decreased while selectivity increased. [ABSTRACT FROM AUTHOR]

The “trapezoid” or “triangle” model constitutes the most popular approach to remote sensing (RS) of surface soil moisture based on coupled thermal (i.e., land surface temperature) and optical RS observations. The model, hereinafter referred to as Thermal-Optical TRAapezoid Model (TOTRAM), is based on interpretation of the pixel distribution within the land surface temperature - vegetation index ( LST - VI ) space. TOTRAM suffers from two inherent limitations. It is not applicable to satellites that do not provide thermal data (e.g., Sentinel-2) and it requires parameterization for each individual observation date. To overcome these restrictions we propose a novel OPtical TRApezoid Model (OPTRAM), which is based on the linear physical relationship between soil moisture and shortwave infrared transformed reflectance ( STR ) and is parameterized based on the pixel distribution within the STR - VI space. The OPTRAM-based surface soil moisture estimates derived from Sentinel-2 and Landsat-8 observations for the Walnut Gulch and Little Washita watersheds were compared with ground truth soil moisture data. Results indicate that the prediction accuracies of OPTRAM and TOTRAM are comparable, with OPTRAM only requiring observations in the optical electromagnetic frequency domain. The volumetric moisture content estimation errors of both models were below 0.04 cm 3 cm − 3 with local calibration and about 0.04–0.05 cm 3 cm − 3 without calibration. We also demonstrate that OPTRAM only requires a single universal parameterization for a given location, which is a significant advancement that opens a new avenue for remote sensing of soil moisture. [ABSTRACT FROM AUTHOR]

Infinite series solutions are obtained for electrical potential, electroosmotic velocity, ionic conductance, and surface physicochemical properties of long pH-regulated rectangular nanochannels of low surface potential utilizing the double finite Fourier transform method. Closed form expressions are also obtained for channels of large height to width ratio for which the depthwise variations vanish. Neglecting the Stern layer impact, the effects of EDL (Electric Double Layer) overlap, multiple ionic species, and association/dissociation reactions on the surface are all taken into account. Moreover, finite-element-based numerical simulations are conducted to account for the end effects as well as to validate the analytical solutions.We show that, with the exception of the migratory ionic conductivity, all the physicochemical parameters are strong functions of the channel aspect ratio. Accordingly, a slit geometry is not a good representative of a rectangular channel when the width is comparable to the height. It is also observed that the distribution of the electrical potential is not uniform over the surface of a charge-regulated channel. In addition, unlike ordinary channels for which an increase in the background salt concentration is always accompanied by higher flow rates, quite the opposite may be true for a pH-regulated duct at higher salt concentrations. [ABSTRACT FROM AUTHOR]

Background: Subjects with Spinal Cord Injury (SCI) should use various assistive devices to stand and walk. Unfortunately they suffer from slow walking speed, high energy consumption, and too much force applied on upper limb while walking. The aim of this study was to determine the gap between the gait performance of SCI and normal subjects to conclude how the performance of SCI can be improved.Method: Three groups of SCI walked with orthosis, SCI walked without orthosis, and normal subjects were recruited in this study. The normal subjects also walked with the same orthoses as SCI subjects. Some parameters such as ranges of motion of hip, knee and spatiotemporal gait parameters were evaluated by use of Qualysis motion analysis system. The difference between the gait parameters of three groups were evaluated by use of two sample t test.Results: The mean values of hip joint range of motion of normal subjects while walking with and without orthosis were 48.3 ± 2.5 and 18.5 ± 8.8 degrees, respectively (p-value = 0.00). There was a significant difference between walking speed of normal subjects with and without orthosis. The walking speed of SCI subject with and without orthosis differed significantly.Conclusion: Although use of orthosis enable SCI subjects to stand and walk, but has some restrictions. As use of orthosis decreased the abilities of normal subjects it can be concluded that more attention should be done on design of orthosis and style of walking. [ABSTRACT FROM AUTHOR]

In this work, energy and quality attributes for deep bed drying of paddy were studied. Drying experiments of freshly harvested paddy were conducted at different levels of drying air parameters including temperature (T=40, 50, 60, 70 and 80 °C), velocity (V=0.5, 0.8 and 1.1 m s −1 ) and relative humidity (RH=40%, 50%, 60% and 70%). It was observed that increasing temperature and velocity increased drying rate and higher levels of relative humidity led to longer drying durations. Total energy consumption ranged from 0.37 kW h to 1.85 kW h where the minimum and maximum values belonged to the experiments carried out at T=80 °C, V=0.5 m s −1 and RH=40%, and T=40 °C, V=1.1 m s −1 and RH=70%, respectively. The results of energy analysis showed that the energy efficiency was improved at higher temperatures, and lower levels of velocity and relative humidity for drying air. Furthermore, it was found that the number of fissured kernels was directly related to drying rate where damaged kernels increased with increasing drying rate. [ABSTRACT FROM AUTHOR]