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Objective: The aim of this study was to validate the ability of cone beam computed tomography (CBCT) to measure condylar internal trabecular bone structure and bone texture parameters accurately.Study Design: Sixteen resected condyles of individuals undergoing temporomandibular joint replacement were collected and used as samples. These condyles were then radiographically imaged by using clinically oriented dental CBCT and research oriented micro-computed tomography (micro-CT). The CBCT scans were then compared with the gold standard micro-CT scans in terms of 21 bone imaging parameters. Descriptive histologic investigation of the specimens was also performed.Results: Significant correlations were found for several imaging parameters between the CBCT and micro-CT images, including trabecular thickness (r = 0.92), trabecular separation (r = 0.78), bone volume (r = 0.90), bone surface area (r = 0.79), and degree of anisotropy measurements (r = 0.77).Conclusions: Measurements of trabecular thickness, trabecular separation, bone volume, bone surface area, and degree of anisotropy obtained from high-resolution dental CBCT images may be suitable bone imaging biomarkers that can be utilized clinically and in future research. [ABSTRACT FROM AUTHOR]

Nano-Tin oxide was synthesized using hydrothermal method at 150 °C for 6 h and then thin films were deposited by electrophoretic method at an optimized voltage of 100 V for 5 min on electropolished aluminum substrate. Spherical particles of about 30–50 nm diameters are observed with partial agglomeration when observed under electron microscope, which are tetragonal rutile structure. XPS results showed peaks related to Sn 4 d , Sn 3 d , O 1 s & C 1 s with spin–orbit splitting of 8.4 eV for Sn 3 d . Feasibility studies of enzyme less urea sensing characteristics of nano-tin oxide thin films are exhibited herein. The deposited films have been used for enzyme less urea sensing from 1 to 20 mM concentration in buffer solution. The sensors were characterized electrochemically to obtain cyclic voltammogram as a function of urea concentration and scan rate. The sensitivity is estimated as 18.9 μA/mM below 5 mM and 2.31 μA/mM above 5 mM with a limit of detection of 0.6 mM. [ABSTRACT FROM AUTHOR]

A series of cyclic acyl guanidine with carbamate moieties have been synthesized and evaluated in vitro for their AChE and BChE inhibitory activities. Structure−activity relationships identified compound 23 as a nanomolar and selective BChE inhibitor, while compound 32 exhibited nanomolar and selective AChE inhibition, selectivity depending on both the structure of the carbamate substituent as well as the position of guanidines- N substitution. The velocity of enzyme carbamoylation was analyzed and showed similar behavior to physostigmine. Phenolic compounds formed after carbamate transfer to the active site of cholinesterases showed additional neuroprotective properties on a hippocampal neuronal cell line (HT-22) after glutamate-induced intracellular reactive oxygen species generation. [ABSTRACT FROM AUTHOR]

Selective and nanomolar acetylcholinesterase inhibitors were obtained by connecting tri- and tetracyclic quinazolinones—previously described as moderately active and unselective cholinesterase (ChE) inhibitors—via a hydroxyl group in para position to an anilinic nitrogen with different amines linked via a three carbon atom spacer. These tri- and tetracyclic quinazolinones containing different alicyclic ring sizes and connected to tertiary amines were docked to a high-resolution h AChE crystal structure to investigate the preferred binding mode in relation to results obtained by experimental structure–activity relationships. While the ‘classical orientation’ locating the heterocycle in the active site was rarely found, an alternative binding mode with the basic aliphatic amine in the active center (‘inverted’ orientation) was obtained for most compounds. Analyses of extended SARs based on this inverted binding mode are able to explain the compounds’ binding affinities at AChE. [ABSTRACT FROM AUTHOR]

Abstract: The main objective of the present study is to investigate how the thermal, rheological, mechanical and cytotoxicity behavior of High Density Polyethylene (HDPE) can be changed by the addition of graphite nano particles (GNPs) at different contents. The HDPE/GNPs composites were prepared using melt blending in a co-rotating intermeshing twin screw extruder. The in vitro tests results showed that the original material (HDPE) and all HDPE/GNPs composites do not exhibit any cytotoxicity to the WISH cell line. The microscopic examination of the nano-composite tensile-fractured surface found a good distribution of GNPs in the HDPE matrix. The Differential Scanning Calorimetry (DSC) results indicated that the crystallization percentage increased by adding GNPs to HDPE up to 4%. The XRD patterns of the HDPE/GNPs composites showed an increase in peak intensity compared to neat HDPE. This increase echoed the crystallinity results obtained from DSC. The rheological tests showed that the complex viscosity of the HDPE increased as the percentage of GNPs increased due to the restriction of the molecular mobility. The tensile test results showed that with increasing the GNPs content, Young’s modulus and the yield strength of the HDPE/GNPs composite increased while the strain at fracture decreased. Finally, the preliminary results of the abrasion test indicated that the abrasion rate decreased by increasing the GNPs ratio up to 4% content. The prepared HDPE/GNPs composites appear to have fairly good comprehensive properties that make them a good candidate as a bearing material for the total joint replacement. [Copyright &y& Elsevier]

Abstract: In previous work by Fouad (Medical Engineering and Physics 2010 ), 3D finite element (FE) models for fractured bones with function-graded (FG) bone-plates and traditional bone-plates made of stainless steel (SS) and titanium (Ti) alloy were examined under compressive loading conditions using the ABAQUS Code. In this study, the effects of the presence of the torsional load in addition to the compressive load on the predicted stresses of the fracture fixation bone-plate system are examined at different healing stages. The effects on the stress on the fracture site when using contacted and non-contacted bone-plate systems are also studied. The FE modelling results indicate that the torsional load has significant effects on the resultant stress on the fracture fixation bone-plate system, which should be taken into consideration during the design and the analysis. The results also show that the stress shielding at the fracture site decreases significantly when using FG bone-plates compared to Ti alloy or SS bone-plates. The presence of a gap between the bone and the plate results in a remarkable reduction in bone stress shielding at the fracture site. Therefore, the significant effects of using an FG bone-plate with a gap and the presence of torsional load on the resultant stress on the fracture fixation bone-plate system should be taken into consideration. [Copyright &y& Elsevier]

Abstract: In the present study, different series of High Density Polyethylene (HDPE)/carbon nano-composites were prepared using melt blending in a co-rotating intermeshing twin screw extruder. The morphological, thermal, rheological, viscoelastic, mechanical, and fracture toughness properties of the nano-composites were analyzed. The microscopic examination of the cryogenically fractured surface found a good distribution of carbon nano-particles in the HDPE matrix. The melting temperature was not significantly affected by the addition of nano-carbon. Whereas, the crystallization percentage was slightly affected by adding carbon nano-particles into the matrix. The complex viscosity increased as the percentage of carbon increased. The Dynamic Mechanical Analysis (DMA) showed that the storage modulus increased with increasing the carbon nano-particles ratio and with increasing the testing frequency. The tensile test results showed that with increasing the carbon nano-particles contents, the Young’s modulus, yield strength of HDPE nano-composite increased while the strain at fracture decreased. Similarly, the fracture toughness and the strain energy release rate decreased proportional to the carbon content. [Copyright &y& Elsevier]

Abstract: In the present study, 3D finite element models for fractured bones with function-graded (FG) bone-plates and traditional bone-plates made of stainless steel (SS) or titanium (Ti) alloy are generated using the ABAOUS code. The predicted Von Mises stresses at the fracture site and underlying bone-plate are examined at different healing stages. The effects on the predicted Von Mises stresses at the fracture site of the presence of a gap between the plate and fractured bone are also studied. Based on the analytical results, it is found that the stress shielding at the fracture site at the fully healed stages decreases when using FG bone-plates compared to Ti alloy or SS bone-plates. In the initial healing stages, the Von Mises stresses at the fracture site increase (stress shielding decreases) by 17% and 11% when using FG bone-plates as compared to SS bone-plates for contacted and non-contacted bone-plate system, respectively. The significant effects of using an FG bone-plate with a gap on the resultant Von Mises stresses on the bone underneath the plate and on the bone stress shielding should be taken into consideration during fractured bone fixation. [ABSTRACT FROM AUTHOR]

Abstract: In the present work, both experimental work and Finite Element Modeling (FEM) have been used to study the effects of notch geometry on the stress/strain behaviour and fracture of the ultra-high molecular weight polyethylene (UHMWPE) at quasi static conditions. The effects of notch profile radii on UHMWPE fracture behaviour, predicted stress/strain distribution, triaxial state of stress and hydrostatic pressure across the neck have been studied. Different techniques have been used to study the effects of notch geometry on the UHMWPE properties. Differential Scanning Calorimetry (DSC) has been used to study the changes in the tested material crystallinity. The universal testing machine has been used to measure the changes in the tested material mechanical properties. The SEM has been used to examine the change in the tested material fracture surface. Finally, the Finite Element Code (ANSYS10) has been used to investigate the effects of notch geometry on the predicted stress/strain distribution across the neck. The results show a notch strengthening behaviour for the tested material, where the axial yield properties increased significantly with the reduction of notch radii, while the axial ultimate properties decreased significantly for the notched specimens compared with plain ones. Also the predicted stress/strain distribution and stress triaxiality show a strong dependence on the notch geometry. The remarkable effects of notch geometry on the predicted stress/strains distributions across the neck show the importance of careful design of UHMWPE artificial joint components with the aim to eliminate the presence of stress risers such as undercuts and fillets. [Copyright &y& Elsevier]

Abstract: The present work was undertaken to examine the effect of some environmental media (sodium hydroxide NaOH solution, water, ice, UV irradiation dose and pre-heat treatment) on the mechanical (quasi-static tensile creep-recovery and relaxation) and physical/thermal (melting and crystallinity) behaviour of the ultra high molecular weight polyethylene (UHMWPE-GUR 410-medical grade), that has several biomedical and engineering applications. The results show changes in the mechanical properties due to these environmental effects. The pre-heat treatment has significantly enhanced the tensile properties compared to virgin specimens’ properties. Improvement due to pre-heat treatment at 100°C is more than that at 50°C. Specimens’ storing in ice, NaOH and water has not affected significantly the tensile properties. All properties except fracture strain have enhanced due to specimens exposure to UV irradiation. The differential scanning calorimetry results indicate that environmental media have not any noticeable effects on the melting temperature. However, a significant increase in the degree of crystallinity was observed for all specimens versus that for virgin specimens. The creep and permanent strains of the tested virgin material increase with temperature and lineally increase with applied load. The specimens’ exposure to environmental media has improved the creep resistance and the permanent creep strain when compared with that for virgin ones. Remarkable increase was observed in the initial relaxation and residual stress of the exposed specimens against that for virgin specimens. [Copyright &y& Elsevier]

Abstract: In the present work, a dynamic thermo-mechanical analysis technique has been used to investigate the effect of pre-heat treatments on the visco-elastic properties of Ultra-High Molecular Weight Polyethylene (UHMWPE) as a function of frequency and temperature. These properties include storage modulus (E′) and loss modulus (E″). The UHMWPE specimens were pre-heated at 50, 80 and 100°C for periods of 2 and 4h, respectively. The effect of these pre-heat treatments on the quasi-static mechanical properties (Young''s modulus, yield strength, fracture strength, ductility and micro-hardness) has also been investigated. Finally, the degree of crystallinity of the UHMWPE has been measured as a function of pre-heat treatment time and temperature. The results show a strong dependence of most of these properties on the degree of crystallinity which is a function of pre-heat treatment temperature and duration. [Copyright &y& Elsevier]

A two-dimensional finite element based overland flow model was developed and used to study the accuracy and stability of three numerical schemes and watershed parameter aggregation error. The conventional consistent finite element scheme results in oscillations for certain time step ranges. The lumped and the upwind finite element schemes are tested as alternatives to the consistent scheme. The upwind scheme did not improve on the stability or the accuracy of the solution, while the lumped scheme provided stable and accurate solutions for time steps twice the size of time steps needed for the consistent scheme. A new accuracy based dynamic time step estimate for the two-dimensional overland flow kinematic wave solution is developed for the lumped scheme. The newly developed dynamic time step estimates are functions of the mesh size, and time of concentration of the watershed hydrograph. Due to lack of analytical solutions, the time step was developed by comparing numerical solutions of various levels of discretization to a reference solution using a very fine mesh and a very small time step. The time step criteria were tested on a different set of problems and proved to be adequate for accurate and stable solutions. A sensitivity analysis for the watershed slope, Manning’s roughness coefficient and excess rainfall rate was conducted in order to test the effect of parameter aggregation on the stability and accuracy of the solution. The results of this analysis show that aggregation of the slope data resulted in the highest error. The roughness coefficient had a smaller effect on the solution while the rainfall intensity did not show any significant effect on the flow rate solution for the range of rainfall intensity used. This work pioneers the challenge of providing guidelines for accurate and stable numerical solutions of the two-dimensional kinematic wave equations for overland flow. [Copyright &y& Elsevier]

Solving the kinematic wave equations for overland flow using the conventional consistent Galerkin finite element scheme is known to result in numerical oscillations due to the non-symmetric first spatial derivative terms in the kinematic wave equations. In this paper the lumped and the upwind finite element schemes are evaluated as alternatives to the consistent Galerkin finite element scheme. Stability analysis of the upwind scheme shows that the damping effect, that could reduce the oscillations, is small for the high Courant numbers encountered in overland flow problems. The upwind scheme, using upwind factors of 0.1 and 1.0, did not provide any improvement to the stability of the lumped and the consistent schemes. The lumped scheme considerably reduces oscillations without significant reduction in the overall solution accuracy. No analytical guidelines for time-step criteria that will insure stability and accuracy were provided by the stability analysis performed for the three schemes. Problem specific accuracy-based dynamic time-step criteria was developed and evaluated for the lumped scheme. These time-steps were found to be on average, double the size of the dynamic time-steps for the consistent scheme. [Copyright &y& Elsevier]

• Traditional health care system fails to predict the exact patient health information. • For the above issue, an IoT sensor with AI is used to predict exact patient details. • Healthcare mobile application is used to collect the patient's information easily. • The gathered patient details are processed according to the IGDBN. Internet of Things (IoT) and Artificial Intelligence (AI) play a vital role in the upcoming years to improve the assistance systems. The IoT devices utilize several sensor devices that able to collect a large volume of data in different domains which is processed by AI techniques to make the decision about the assistance problems. Among several applications, in this work, IoT with AI is used to examine the healthcare sectors to improve patient assistance and patient care in the future direction. Traditional health care assistance system fails to predict the exact patient health information and needs which reduces the accuracy of patient assistance process. For these issues, an IoT sensor with AI is used to predict the exact patient details such as fitness tracker, medical reports, health activity, body mass, temperature, and other health care information which helps to choose the right assistance process. Healthcare mobile application is used to achieve this goal and collect the patient's information. This information is shared in the cloud environment, which is accessed and processed by applying the optimized machine learning techniques. The gathered patient details are processed according to the iterative golden section optimized deep belief neural network (IGDBN). The introduced network examines the patient's details from the previous health information which helps to predict the exact patient health condition in the future direction. The efficiency of IoT sensor with an AI-based health assistance prediction process is developed using MATLAB tool. Excellence is determined in terms of precision (99.87), loss error (0.045), simple matching coefficient (99.71%), Matthews correlation coefficient (99.10%) and accuracy (99.86%). [ABSTRACT FROM AUTHOR]

• PDT and PBT, both laser therapies, were used in the present study. • Higher predominance of cohesive failure was recorded for all groups, irrespective of the final irrigation protocol. • AH Plus showed higher bond strength than MTA Fillapex (p < 0.05). The aim of the present study was to establish an assessment regarding the efficacy of final disinfection protocols and sealers on the bond strength (BS) of root canal (RC) filling materials on root dentin which has already been treated with photobiomodulation (PBT) or photodynamic therapy (PBT) respectively. One-hundred and twenty root canals were included in the present study. The selected teeth were cleaned and shaped to accept the obturation. The prepared specimens were subjected to laser therapy (PBT and PDT) and were randomized into three groups (n = 20/group) on the basis of irrigation technique: Group 1: distilled water (DW) + ultrasonic irrigation (UI); Group 2: 17 % EDTA; Group 3: 0.2 % Chlorhexidine digluconate (CHx) respectively. Each specific group was further divided into two subgroups (n = 10), based on endodontic sealing agent incorporated during obturation: AH Plus or MTA Fillapex. The push-out test was used to gauge the BS, whereas the evaluation was done with the help of two-way ANOVA which was followed by a subsequent Tukey post-hoc test. The chi-square test was used to calculate the mode of failure in the selected specimens (α = 5%). The final irrigation protocols of 17 % EDTA and CHX helped to enhance the BS of RC filling material with either sealer agent used (p < 0.05), whereas, AH Plus reported an increase in the values of BS as compared to its counterpart, MTA Fillapex (p < 0.05). Increased values of cohesive failure were associated with all the groups, irrespective of the tested final irrigation protocols and RC sealer agents (p < 0.05). There was no significant difference between the laser therapies among all the groups (p < 0.05). The use of 17 % EDTA and CHX and sealing material AH Plus increased the BS of the obturation on radicular dentin previously subjected to either of the mentioned laser therapies. Furthermore, no significant effect on the BS was observed with the use of lasers in the study. [ABSTRACT FROM AUTHOR]

• NUG is an acute periodontal infection generally treated by robust periodontal therapy. • Bleeding scores were significantly improved with PCT. • PCT has a large impact in reducing pathogenic bacteria over the period of 6 weeks. This study was designed to investigate the clinical and microbiological parameters with photochemotherapy (PCT) against conventional debridement (CD) among patients with necrotizing ulcerative gingivitis (NUG). Patients with a diagnosis of NUG were divided into two groups: 'Group-PCT' that underwent indocyanine green-mediated PCT with adjunctive mechanical debridement, and Group-CD that underwent mechanical debridement with adjunctive 3 % hydrogen peroxide/chlorhexidine rinse. Clinical inflammatory gingival parameters including full-mouth plaque scores (FMPS), bleeding scores (FMBS), and probing depth (PD) were measured. Counts of Treponema microdentium , Fusobacterium nucleatum and Prevotella intermedia were assessed using polymerase chain reaction technique. All assessments were done at baseline, 3 weeks and 6 weeks. Twenty-six participants were contacted and agreed to participate in the trial. The mean age of participants in group-PCT was 24.5 years while the mean age of patients in group-CD was 26.7 years. FMPS showed significant but equal reduction in both the groups at 3 weeks and 6 weeks (p < 0.01). The reduction in mean FMBS was higher in the group-PCT at 6 weeks follow-up (p < 0.05). All bacterial levels reduced from baseline to follow-up with both PCT and CD groups (p < 0.05). Group-PCT showed significantly reduced counts of T. microdentium and F. nucleatum at 3 weeks and 6 weeks compared with group-CD (p = 0.024). Equal reduction was shown for P. intermedia between both the groups at 3 and 6 weeks, respectively. Application of adjunctive photochemotherapy was both clinically and microbiologically effective in the treatment of NUG. [ABSTRACT FROM AUTHOR]

The use of flexible dental posts concentrates the stress at the dentin and the use of stiff posts increases the stress at the interface. Efforts were directed toward introducing inhomogeneous materials for resolving the disadvantages of both flexible and stiff posts. The main objective of this study was to develop three different fiber/epoxy composite posts. These composites were fabricated using carbon, glass, and Kevlar fibers. Characterization tests were conducted. In the tensile tests, the carbon, glass and Kevlar fiber composites exhibited tensile strengths of 200%, 91%, and 40% of the stainless-steel tensile strength, respectively, and exhibited stiffness values of 62%, 33%, and 12% of the stainless-steel stiffness. The carbon fiber/epoxy composite have a fracture toughness close to that of aluminum alloy. Vibration modal analysis indicated that the frequency response of the carbon fiber composite was lower than those of the glass and Kevlar composites. The highest tensile strength, storage moduli, and stiffness were recorded for the carbon fiber composites and the lowest were for Kevlar fiber composite. The low stiffness and strength of the Kevlar composite are attributed to the fact that Kevlar fibers had lower wettability with epoxy resin than both glass and carbon fibers. Moreover, the Kevlar fiber composite exhibited higher delamination. However, the stiffness and strength of Kevlar made its composite more sensitive than the other composites to free vibrations generated by a simple force induced by a hammer. Based on the results, the carbon fiber/epoxy composite has appropriate characteristics for application in new dental posts. [ABSTRACT FROM AUTHOR]

• Now a days the major oral health issues of man is crucial an area of research. • This paper traces classification, segmentation and pre-processing of dental images. • Histogram based adaptive approach is used in the radiographic X-ray 2d dental Image. • This is useful to distinguish the foreground teeth & the regions of background bones. In the present scenario the major oral health issues of man is crucial an area of research. The Data mining techniques, image processing, and Computational intelligence techniques are playing a vital role in biomedical research. Dental image processing helps to improve the early detection and classification of the diagnostic process to make accurate decisions. The radiographic 2d dental image is widely utilized for analytic thinking of several dental disorders. In this paper traces the complete steps such as classification and segmentation as well as pre-processing of dental images has been carried out. In the pre-processing, histogram based on adaptive approach is used to stretch the contrast and equalize the brightness throughout the radiographic X-ray 2d dental Image. This operation is useful to distinguish the foreground teeth and the regions of background bones. Separation of dental 2d images into regions corresponding to the objects is a fundamental step of segmentation. The hybrid graph cut segmentation is used to segment the oral cavity and its tissues. In this research deep learning based convolution neural network (CNN) has been used to process the dental image and shows promising outcomes with 97.07% accuracy. [ABSTRACT FROM AUTHOR]

In recent times, much attention has been paid to explore economic and highly active precious metal free electrocatalysts for energy conversion and storage systems due to the expensiveness of Pt-based catalysts. Here we developed a mesoporous core-shell like nanospheres composed of a metallic cobalt oxide core wrapped with a polypyrrole nanoshell (PPy/Co 3 O 4 ) for methanol electrooxidation. The performance of the core-shell PPy/Co 3 O 4 nanospheres as anodic catalyst material was measured in 1 M KOH electrolyte and the results obtained demonstrated that the hybrid possesses high catalytic activity in terms of current density and onset voltage. The core-shell PPy/Co 3 O 4 delivers an oxidation current density of ∼111 mA/cm 2 at 0.5 V with superior stability long run stability. The observed electrocatalytic performance of the porous PPy/Co 3 O 4 nanospheres is attributed to the integrative effects of both Co-species and layered carbon shell and presence of exceptionally numerous mesopores. Results show evidence that the earth abundant PPy/Co 3 O 4 provide a potential electrode material for methanol electrooxidation with a satisfactory reaction activity. [ABSTRACT FROM AUTHOR]

Both the acetylcholine esterase (AChE) and the histamine H 3 receptor (H 3 R) are involved in the metabolism and modulation of acetylcholine release and numerous other centrally acting neurotransmitters. Hence, dual-active AChE inhibitors (AChEIs) and H 3 R antagonists hold potential to treat cognitive disorders like Alzheimer's disease (AD). The novel dual-acting AChEI and H 3 R antagonist 7-(3-(piperidin-1-yl)propoxy)-2,3-dihydropyrrolo[2,1- b ]quinazolin-9(1H)-one (UW-MD-72) shows excellent selectivity profiles over the AChE's isoenzyme butyrylcholinesterase (BChE) as well as high and balanced in-vitro affinities at both AChE and h H3R with IC 50 of 5.4 μM on h AChE and h H 3 R antagonism with K i of 2.54 μM, respectively. In the current study, the effects of UW-MD-72 (1.25, 2.5, and 5 mg/kg, i.p.) on memory deficits induced by the muscarinic cholinergic antagonist scopolamine (SCO) and the non-competitive N -methyl- d -aspartate (NMDA) antagonist dizocilpine (DIZ) were investigated in a step-through type passive avoidance paradigm in adult male rats applying donepezil (DOZ) and pitolisant (PIT) as reference drugs. The results observed show that SCO (2 mg/kg, i.p.) and DIZ (0.1 mg/kg, i.p.) significantly impaired learning and memory in rats. However, acute systemic administration of UW-MD-72 significantly ameliorated the SCO- and DIZ-induced amnesic effects. Furthermore, the ameliorating activity of UW-MD-72 (1.25 mg/kg, i.p.) in DIZ-induced amnesia was partly reversed when rats were pretreated with the centrally-acting H 2 R antagonist zolantidine (ZOL, 10 mg/kg, i.p.), but not with the CNS penetrant H 1 R antagonist pyrilamine (PYR, 10 mg/kg, i.p.). Moreover, ameliorative effect of UW-MD-72 (1.25 mg/kg, i.p.) in DIZ-induced amnesia was strongly reversed when rats were pretreated with a combination of ZOL (10 mg/kg, i.p.) and SCO (1.0 mg/kg, i.p.), indicating that these memory enhancing effects were, in addition to other neural circuits, observed through histaminergic H 2 R as well as muscarinic cholinergic neurotransmission. These results demonstrate the ameliorative effects of UW-MD-72 in two in-vivo memory models and provide evidence for the potential of dual-acting AChEI and H 3 R antagonists to treat cognitive disorders. [ABSTRACT FROM AUTHOR]

The design of bivalent ligands targeting G protein-coupled receptors (GPCRs) often leads to the development of new, highly selective and potent compounds. To date, no bivalent ligands for the human cannabinoid receptor type 2 (hCB2R) of the endocannabinoid system (ECS) are described. Therefore, two sets of homobivalent ligands containing as parent structure the hCB2R selective agonist 13a and coupled at different attachment positions were synthesized. Changes of the parent structure at these positions have a crucial effect on the potency and efficacy of the ligands. However, we discovered that bivalency has an influence on the effect at both cannabinoid receptors. Moreover, we found out that the spacer length and the attachment position altered the efficacy of the bivalent ligands at the receptors by turning agonists into antagonists and inverse agonists. [ABSTRACT FROM AUTHOR]

Abstract: Two sets of carbamates based on the natural alkaloid evodiamine were designed, synthesized and evaluated as potential butyrylcholinesterase inhibitors. Although a set of carbamates of 3-hydroxyevodiamine (10a–f) is inactive both at AChE and BChE, carbamates of 5-deoxo-3-hydroxyevodiamine (11a–f) exhibit much better potency with selectivity toward BChE. The heptyl carbamate of 5-deoxo-3-hydroxyevodiamine (11c) shows the best potency with an IC50 value of 77 nM and very good selectivity over AChE. ORAC and cell-based assays indicate 11c owns pronounced antioxidant properties with 1.75 Trolox equivalents and strong neuroprotection even from 1 μM onwards. These combined activities might enable compound 11c to be a potential candidate for treatment of Alzheimer's disease. [Copyright &y& Elsevier]

Natural fibre–reinforced epoxy composites have been increasingly utilised in construction and building applications. These materials introduce cost-effective alternatives to conventional materials and their utilisation often has related to financial advantages that are immediate and can be expected over the structure service life. In this work, the results of thermal, dynamic-mechanical, and thermal-mechanical properties of date palm fibre (DPF)/bamboo fibre (BF) hybrid composite were compared to bamboo fibre-reinforced epoxy to demonstrate the importance of hybridization. The thermal stability was improved when DPF/BF fillers were added in epoxy resin comparatively to BF reinforced epoxy. The glass transition temperature (T g) was increased by incorporating the date palm fibre/bamboo hybrid composite in epoxy compared to the BF reinforced epoxy. The thermal expansion was enhanced by modifying the hybrid composites in epoxy in contrast to the single fibre composites, without hybridisation. Hence, the hybridisation technique of date palm fibre with bamboo has improved the thermal and thermal-mechanical properties suitable for several applications including non-structural applications. [ABSTRACT FROM AUTHOR]

In this research NaOH treated date palm fibres were used as reinforcement in phenolic based composites. The composites were prepared by hot press technique and evaluated tensile flexural, structural, thermo gravimetric dynamic mechanical properties. Overall properties of modification/treatment of fibers' surface enhanced, that have been studied as compared to untreated samples. The treated samples of 50% DPF composites showed highest Tensile properties among all composites but flexural properties declined compared to the untreated composites but this decline is very less. Fibre treatment showed declined properties of three point bending of DPF composites. Scanning Electron Microscopy studied the behavior of fibre and matrix bonding before and after treatment. Treated 50% DPF showed better fibre distribution, 60% DPF showed void content however 40%DPF showed poor fibre/matrix interfacial bonding. Thermogravimetric analysis studied the behavior of Treated DPF/Phenolic composites at high temperature, and found thermal stability enhanced because good interfacial bonding. Dynamic mechanical analysis showed that stability at stress of material with temperature and also studied the energy dissipation and internal friction. Treated 50%DPF showed better properties due to the ratio of mixing of fibre/matrix and better interfacial bonding. DPF composite have potential to use for exterior applications and false wall and roof. [ABSTRACT FROM AUTHOR]

The growing global awareness for environmental protection has inspired the exploration on producing active packaging films from bio-based materials. In present work, three types of active agents were studied by incorporating thymol(T), kesum(K), and curry(C) (10% wt.) into polylactic acid (PLA) to produce PLA-10T, PLA-10K, and PLA10-C packaging films via solvent casting method. The morphology, functional chemistry, thermal stability, permeability, and antimicrobial properties were evaluated for PLA films. Functional chemical analysis confirmed the presence of interfacial bonding between aromatic groups of active agents and PLA carbonyl group. PLA-10K exhibited the highest thermal resistance comparing to PLA-10T and PLA-10C while water vapor barrier was enhanced after incorporation of active agents. Qualitative observation had indicated that chicken meat could be preserved in the active films until 15 days, while odourless and firm texture properties retained in food sample. For disc diffusion assay (in vitro), it showed positive results against Gram-positive bacteria (Staphylococcus aureus) whereas with negative results against Gram-negative bacteria (Escherichia coli) and Aspergillus Brasiliensis due to embedded active agents within PLA matrix. We concluded that produced active agents filled PLA films potential to use in food packaging application to enhance the shelf life of meats, fruits and vegetables product. Unlabelled Image • Fabrication of polylactic acid (PLA) film with active agent for food preservation. • Incorporation of thymol, kesum, and curry oils into PLA matrix via solvent casting. • Smooth cross-section feature showcased by thymol and kesum integrated PLA film. • Stable thermo-molecular changing behavior between kesum and PLA. • Long-lasting time for chicken meat preservation in active agents filled PLA films. [ABSTRACT FROM AUTHOR]

Olive fiber is a renewable natural fiber which has potential as an alternative biomass for extraction of microcrystalline cellulose (MCC). MCC has been widely applied in various industries owing to its small dimensional size for ease of reactive fabrication process. At present study, a serial treatments of bleaching, alkaline and acid hydrolysis was employed to extract OL-BLF, OL-PUF, and OL-MCC respectively from olive stem fiber. In morphology examination, a feature of short micro-crystallite particles was obtained for OL-MCC. The particle size was found gradually reducing from OL-PUF (305.31 μm) to OL-MCC (156.06 μm) due to the disintegration of cellulose fibrils. From physicochemical analysis, most lignin and hemicellulose components had been removed from OL-BLF to form OL-PUF with individually fibril structure. The elemental analysis revealed that highly pure cellulose component was obtained for OL-MCC. Also, the rigidity had been improved from OL-BLF to OL-PUF, while with the highest for OL-MCC with 74.2% crystallinity, endowing it as a reliable load-bearing agent. As for thermal analysis, OL-MCC had the most stable heat resistance in among the chemically-treated fibers. Therefore, olive MCC could act as a promising reinforcing agent to withstand harsh conditions for variety fields of composite applications. [ABSTRACT FROM AUTHOR]

• To analyze the tooth decay and acid erosion from European teeth biomedical data. • To collect information from children having age 5. • The teeth decay activities are monitored by EMOCA algorithm with RTRFNN. • To analyze the changes & characteristics of children biomedical teeth data. Now-a-days most of the children faced tooth decay and acid erosion problem in their teeth because of continuous bacterial infection, acid segregation, presents of food particles in teeth and so on. Especially, children are more affected by tooth decay, that leads to create severe problem like gingivitis, teeth loss and teeth pain. Due to the importance of tooth decay it needs to predict in earlier condition for eliminating children teeth problem such anorexia and bulimia disorders. Hence the bacterial infection of teeth is critical to be predicted from affected teeth. So, in this paper we analyze the tooth decay and acid erosion from European teeth biomedical data portal which collects information from children having age 5. The teeth decay activities are monitored by evolutionary multi-objective cuckoo feature selection (EMOCA) algorithm with Ruzzo–Tompa optimized regulatory feedback neural network (RTRFNN) that successfully analyze the changes and characteristics of children teeth biomedical teeth data. The introduced method effectively evaluates children tooth data before making the final decision about tooth decay and acid erosion. Then the excellence of the system is evaluated with the help of the experimental results, Ruzzo–Tompa optimized regulatory feedback neural network recognize the abnormal dental features with 99.22% of accuracy. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Facile synthesis of pure and Sn-doped vanadium oxide (V 2 O 5) nanoparticles. • Fabrication of Optical ammonia gas sensors based on synthesized nanoparticles. • High optical sensing response (77.84%) for synthesized 2 wt% Sn doped V 2 O 5 nanoparticles towards ammonia gas. Abstract Herein, we present the synthesis, characterization and optical ammonia gas sensing of pure and Sn-doped vanadium oxide (V 2 O 5) nanoparticles prepared by the sol-gel process. The V 2 O 5 nanoparticles were doped with Sn concentrations of 2 wt%–6 wt%, and characterized using X-ray diffraction, atomic force microscopy, UV–vis spectroscopy and photoluminescence spectroscopy which confirmed the orthorhombic crystal structure. The crystalline size was found to decrease with enhancing the doping concentrations of Sn. The lattice-strain and crystalline size with the peak-broadening of pure and Sn doped V 2 O 5 nanoparticles were analyzed by William-Hall (W-H) method and size-strain plot. The UV–vis absorption showed a decrease in the energy band gap (3.27 eV–3.07 eV) with an increase in the Sn doping concentration. The Sn-doped V 2 O 5 nanoparticles were used to detect ammonia gas (5–50 ppm) through photoluminescence based detection method. Interestingly, it was observed that the optical response for the 2 wt% Sn doped V 2 O 5 nanoparticles was maximum (77.84%) towards 50 ppm ammonia compared to other V 2 O 5 nanoparticles based samples. [ABSTRACT FROM AUTHOR]

In recent work, we demonstrated the successful fabrication of core-shell nanofiber composites with enhanced tensile, surface wetting and cytocompatibility properties via coaxial electrospinning using PLA and PVA. It has been shown that core/shell-structured PLA/PVA nanofiber mat has the hydrophilic benefits of PVA and the attractive biological properties of PLA. In this paper, we present detailed mechanical evaluation of the electrospun coaxial nanofiber mats under static, dynamic and creep loading. The core/shell-PLA/PVA nanofibers showed nearly 233% and 150% increase in tensile strength and ductility, respectively, compared to pristine PLA. Dynamic loading tests were employed to study the viscoelasticity of the coaxial core-shell composite nanofibers at various temperatures and frequencies. The results of the storage and loss moduli of the coaxial nanofibers suggested strong physical interaction between the PLA and PVA layers, that contribute to the observed good mechanical behaviour. The better creep resistance of the coaxial PLA/PVA nanofibers under axial loading compared to the pristine materials provides further evidence for the physical interaction between the two constituent materials. A simple linear viscoelastic model is used to quantify the evolution of creep strain in pristine and coaxial materials. This research may help to understand the physical relation between the observed viscoelastic behaviour and the internal structure of coaxial core/shell nanofibers of PLA and PVA. [ABSTRACT FROM AUTHOR]

The development of energy storage materials with high capacity and rapid charging and discharging ability have become the most important and major issues of concern in recent years. In this study, a mesoporous nickel sulfide (NiS) hierarchical framework was synthesized using a simple solvothermal method under optimized experimental conditions, including the amount of sulfur and experimental time, and characterized using a range of spectroscopic and microscopic techniques. The resulting materials were tested further as electrode materials in an electrochemical half-cell assembly and full cell solid-state symmetric assembly cell. The optimized mesoporous nickel sulfide hierarchical showed excellent specific capacitance performance with outstanding cycling stability (∼88.57%) after 5000 consecutive charge discharge cycles. A prototype symmetric supercapacitor device was also assembled using hierarchical flower-like NiS and the measured device performance showed a high capacitance of 11.15 F/g, high energy density of 0.991 Wh/kg at a power density of 132 W/kg, and at power density of 261.11 W/kg at an energy density of 0.329 Wh/kg, and excellent cycling stability (83.8% with 92.9% coulombic efficiency after 2000 cycles at 0.26 A/g). The potential applications of the above device were demonstrated by powering a light emitting diode and commercially available fan for more than 30s discharging time. [ABSTRACT FROM AUTHOR]

Oxygen reduction reaction (ORR) catalysts are the heart of eco-friendly energy resources particularly low temperature fuel cells. Although valuable efforts have been devoted to synthesize high performance catalysts for ORR, considerable challenges are extremely desirable in the development of energy technologies. Herein, we report a simple self-polymerization method to build a thin film of dopamine along the tubular nanostructures of multi-walled carbon nanotubes (CNT) in a weak alkaline solution. The dopamine@CNT hybrid (denoted as DA@CNT) reveals an enhanced electrocatalytic activity towards ORR with highly positive onset potential and cathodic current as a result of their outstanding features of longitudinal mesoporous structure, high surface area, and ornamentation of DA layers with nitrogen moieties, which enable fast electron transport and fully exposed electroactive sites. Impressively, the as-obtained hybrid afford remarkable electrochemical durability for prolonged test time of 60,000 s compared to benchmark Pt/C (20 wt%) catalyst. Furthermore, the developed DA@CNT electrode was successfully applied to access the quality of antiviral drug named Valacyclovir (VCR). The DA@CNT electrode shows enhanced sensing performance in terms of large linear range (3–75 nM), low limit of detection (2.55 nM) than CNT based electrode, indicating the effectiveness of the DA coating. Interestingly, the synergetic effect of nanostructured DA and CNT can significantly boost the electronic configuration and exposure level of active species for ORR and biomolecule recognition. Therefore, the existing carbon-based porous electrocatalyst may find numerous translational applications as attractive alternative to noble metals in polymer electrolyte membrane fuel cells and quality control assessment of pharmaceutical and therapeutic drugs. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)-incorporated TiO 2 nanofibers was successfully synthesized via a simple and effective technique, electrospinning and applied as a working electrode for dye sensitized solar cells (DSSCs). The effects of graphene oxide on the structural and photoelectric conversion performance of the DSSCs were inspected by various analytical techniques. The results suggest that presence of graphene oxide increases the amount of dye absorption which leads to high migration of photoinduced electrons to the conduction band of the collection electrode and inhibition of electron recombination. Furthermore, the presence of graphene oxide improves the electron transport from the films to the fluorine doped tin oxide (FTO) substrates. Accordingly, remarkably enhanced power conversion efficiency of 4.52% was observed in case of utilizing 0.5 wt% graphene oxide-incorporated TiO 2 nanofibers as working electrode based DSSC which is higher than that of the conversion efficiency in case of pristine TiO 2 nanofibers (i.e. 1.54%). The high amount of graphene oxide content results in decrease the power conversion efficiency. Therefore, it can be claimed that graphene oxide-incorporated TiO 2 nanofibers as working electrode is a promising candidate for improving the performance of the DSSCs. [ABSTRACT FROM AUTHOR]

• TIA and DCIA positively affect the probability of runoff yield. • DCIA contributes far more than TIA to generating far-above-average runoff depth. • The contributions of TIA and DCIA to far-above-average peak flow are comparable. • The impacts of TIA and DCIA are subject to climate variability. • TIA and DCIA control is effective within a specific range of rainfall depth. Total impervious area (TIA) is one of the most common measures for predicting runoff yield in hydrologic studies and regulating urbanization in land use policy. Directly connected impervious area (DCIA), a subset of TIA, represents the hydraulic connection between development and underground sewer systems. Which indicator to use in runoff prediction has been subject to debate. The effectiveness of TIA and DCIA in the face of climate variability also remains unclear. The present study empirically assessed the impacts of TIA and DCIA on urban runoff in three metropolitan statistical areas (MSAs) in the U.S. state of Texas. The total monthly runoff depths of 92 watersheds and peak flows of 43 watersheds were computed using streamflow monitored by the U.S. Geological Survey from 2010 to 2017. A series of ordinal logit regression models were developed to determine which imperviousness indicator better predicted probable runoff yield. Additionally, an average marginal effect analysis was performed to investigate how TIA and DCIA responded to changing precipitation depths. The results demonstrate that DCIA outperformed TIA in runoff depth prediction, whereas TIA predicted peak flow better than DCIA. However, for far-above-average runoff, the contribution of DCIA to runoff depth was far greater than that of TIA, but no difference was found for peak flow. The effectiveness of TIA and DCIA also varied by total and 24-hour peak depths of monthly precipitation. After reaching their maximum capacity, both TIA and DCIA became less effective in predicting runoff and did not correlate with rainfall depth in extremely wet months. Meanwhile, the control of TIA and DCIA for runoff volume reduction was most effective for monthly rainfall of a 5% to 10% probability of exceedance in all MSAs, whereas that of peak flow reduction was most effective if the 24-hour peak storm in a month had a 2% to 5% probability of exceedance. The findings of this study demonstrate the hydrologic significance of regulating DCIA over TIA for high-risk runoff under certain rainfall depths and return periods. The study expands the current knowledge of urban hydrology for effective stormwater management and mitigation of future flooding risk. [ABSTRACT FROM AUTHOR]