Dynamic mechanical properties of Polyurethane Shape Memory Polymer Composites (SMPC) with different volume fractions of chopped strand mat glass fiber

Polyurethane shape memory polymer (SMP) are comparatively low in modulus. Hence, there is a need for incorporation of chopped strand mat glass fibers as reinforcing materials for the development of SMP composites (SMPC). In this study, glass fibers in different volume fractions which are 0%, 5%, 10%, 15% and 30% were used. The aim is to obtain the optimum volume fractions of glass fibers in SMPC based on the dynamic mechanical properties. The dynamic mechanical analysis (DMA) was carried out to determine the dynamic mechanical properties of the composite material. The dynamic parameters which reliance to temperature such as storage modulus (E’), loss modulus (Eâ€), damping factor (tan δ), glass transition temperature (Tg) values and others will gives the data regarding the adhesion of fiber-matrix of the composite material. The result shows that upon the addition of reinforcing fibers, an improvement in storage modulus was obtained. The tan δ peak value were decrease when the fiber volume fractions were increased, which confirming the reinforcing effectiveness of glass fibers in SMPC. It was also observed that the (Tg) increase upon the addition of reinforcing glass fibers. Summarizing, 15SMPC was chosen as the optimum volume fractions of glass fibers in SMPC. The parameter of the damping vibration demonstrates main significance for civil applications for building reliability and performance enhancement. Besides, it can foresee the impacts of temperature and time towards the polymer viscoelastic performance under various conditions. This study will provide several information to determine its functional application in future research

Plasma von Willebrand factor levels predict in-hospital survival in patients with acute-on-chronic liver failure

BACKGROUND AND AIMS: Circulating levels of von Willebrand factor (vWF) predict mortality in patients with cirrhosis. We hypothesized that systemic inflammation in acute-on-chronic liver failure (ACLF) will stimulate endothelium, increase vWF levels, and promote platelet microthrombi causing organ failure. METHODS: In this prospective study, we correlated plasma vWF levels with organ failure, liver disease severity, sepsis, and systemic inflammatory response syndrome (SIRS) and also analyzed if vWF levels predicted in-hospital composite poor outcome (i.e. death/discharged in terminal condition/liver transplantation) in consecutive ACLF patients. RESULTS: Twenty-one of the 50 ACLF patients studied had composite poor outcome. ACLF patients had markedly elevated vWF antigen and activity (sevenfold and fivefold median increase, respectively) on days 1 and 3. Median ratio of vWF to a disintegrin and metalloprotease with thrombospondin type 1 motif, member 13 (ADAMTS13) activity on day 1 was significantly higher in ACLF patients (11.2) compared to 20 compensated cirrhosis patients (3.3) and healthy volunteers (0.9). On day 1, area under ROC curve (AUROC) to predict composite poor outcome of hospital stay for ACLF patients for vWF antigen, vWF activity, and model for end-stage liver disease (MELD) score were 0.63, 0.68, and 0.74, respectively. vWF activity correlated better with liver disease severity (MELD score, ACLF grade) and organ failure (Sequential Organ Failure Assessment [SOFA] score) than vWF antigen; in contrast, neither vWF antigen nor activity correlated with platelet count, sepsis, or SIRS. CONCLUSIONS: vWF levels are markedly elevated, correlate with organ failure, and predict in-hospital survival in ACLF patients. This data provides a mechanistic basis for postulating that vWF-reducing treatments such as plasma exchange may benefit ACLF patients

Suzuki-Miyaura coupling under microwave enhanced conditions: Synthesis of 2-(hetero)aryl benzimidazoles

An expedient, palladium-mediated cross-coupling approach to functionalize the benzimidazole-based core under microwave-assisted conditions has been developed and is described. This protocol, which incorporates appendage diversity on this potential scaffold, is found to be compatible with a wide range of electronicallyand sterically-divergent (hetero)aryl boronic acids. The use of the PdCl2/(SPhos) catalytic system allows the formation of a stable and highly active LPd(0) species which was found to be critical for the successful synthesis of these novel, pharmacologically-relevant molecules. © AUTHOR(S).Russian Foundation for Basic Research, RFBR: 170300641AThe authors are thankful to SAIF, Indian Institute of Technology, Madras, for providing all the analytical data and spectra. Vasiliy A. Bakulev is thankful to Russian Foundation for Basic Research (Grant # 170300641A)

Design and synthesis of diazine-based panobinostat analogues for HDAC8 inhibition

© 2020 Balasubramaniam et al. Guided by computational analysis, herein we report the design, synthesis and evaluation of four novel diazine-based histone deacetylase inhibitors (HDACis). The targets of interest (TOI) are analogues of panobinostat, one of the most potent and versatile HDACi reported. By simply replacing the phenyl core of panobinostat with that of a diazine derivative, docking studies against HDAC2 and HDAC8 revealed that the four analogues exhibit inhibition activities comparable to that of panobinostat. Multistep syntheses afforded the visualized targets TOI1, TOI2, TOI3-rev and TOI4 whose biological evaluation confirmed the strength of HDAC8 inhibition with TOI4 displaying the greatest efficacy at varying concentrations. The results of this study lay the foundation for future design strategies toward more potent HDACis for HDAC8 isozymes and further therapeutic applications for neuroblastoma

Extrapontine myelinolysis presenting as acute parkinsonism

BACKGROUND: Extrapontine myelinolysis presenting with extra pyramidal features suggestive of parkinsonism may be a challenging clinical syndrome. Clinicians should maintain their vigilance while correcting electrolyte imbalances, especially with associated co-morbidity. CASE PRESENTATION: A 41-year-old woman presented with acute parkinsonism like features while on a holiday. This followed slow correction of hyponatraemia after repeated vomiting. MRI changes were suggestive of Extrapontine myelinolysis(EPM). This case is at variance with four previous cases reported in the medical literature in that the patient made a full clinical recovery and the MR changes resolved with symptomatic support alone. CONCLUSION: Extrapontine myelinolysis could make a complete recovery with symptomatic support alone. During hyponatraemia correction, rapid osmotic shifts of fluid that cause hypernatremia, causes myelinolysis rather than absolute serum sodium level. Even gradual correction of hyponatraemia can produce myelinolysis, especially with pre-existing malnourishment, alcoholism, drug misuse, Addison's disease and immuno-suppression. Pallidial sparing is typical of EPM in MRI scans

Transient parkinsonism in isolated extrapontine myelinolysis

Extrapontine myelinolysis (EPM) is a rare cause of parkinsonism. In this case report, we describe a 63-year-old woman with parkinsonism due to EPM after correction of hyponatremia. During a 4-year follow-up, both the clinical features of parkinsonism and the changes on magnetic resonance imaging resolved. Parkinsonism due to EPM should be recognized as it has a good prognosis

Synthesis, Crystal structure, DFT calculations and antimicrobial activity of 4-(4-fluoro-phenyl)-2,6-dimethyl-1,4-dihydro-pyridine-3,5-dicarboxylic acid diethyl ester

The title compound was synthesized and confirmed by FT-IR, 1H, 13C NMR analysis. The molecular structure of the compound was precisely determined by Single Crystal X-ray Diffraction (SC-XRD) analysis. The crystalized compound shows P21/C & monoclinic crystal system with cell parameters a = 9.7768 (5), b = 7.4005(3) and c = 24.8099 (12), β=93.734(2)°.The structural and electronic properties of the compound were carried out by Density Functional Theory (DFT) calculations. The compound exhibited H-bonding between N1-H1A-O1 with bond distance 2.98(7) A°).The energy gap Egap 4.53eV and Egap= 4.34eV for crystal and DFT method respectively. The molecular orbitals energies were studied through Highest Unoccupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) analysis. The softness and hardness of the molecule was studied through Global Chemical Reactivity Descriptors (GCRD). The electrophilic and nucleophilic characters were studied through Molecular Electrostatic Potential (MEP) studies. The antimicrobial studies were carried out by in-vitro method against 6 microorganisms

PALLADIUM CATALYZED SYNTHESIS OF NOVEL TACRINE DERIVATIVES

This work was supported by Ministry of Science and Higher Education of the Russian Federation, grant # 075-15-2020-777 and the Russian Science Foundation, grants ### 22-23-20189, 21-13-00304 and 20-73-10205

MULTIPLE OIL PAD DETECTION USING DEEP LEARNING

Deep learning (DL) algorithms are widely used in object detection such as roads, vehicles, buildings, etc., in aerial images. However, the object detection task is still considered challenging for detecting complex structures, oil pads are one such example: due to its shape, orientation, and background reflection. A recent study used Faster Region-based Convolutional Neural Network (FR-CNN) to detect a single oil pad from the center of the image of size 256 × 256. However, for real-time applications, it is necessary to detect multiple oil pads from aerial images irrespective of their orientation. In this study, FR-CNN was trained to detect multiple oil pads. We cropped images from high spatial resolution images to train the model containing multiple oil pads. The network was trained for 100 epochs using 164 training images and tested with 50 images under 3 different categories. with images containing: single oil pad, multiple oil pad and no oil pad. The model performance was evaluated using standard metrics: precision, recall, F1-score. The final model trained for multiple oil pad detection achieved a weighted average for 50 images precision of 0.67, recall of 0.80, and f1 score of 0.73. The 0.80 recall score indicates that 80% of the oil pads were able to identify from the given test set. The presence of instances in test images like cleared areas, rock structures, and sand patterns having high visual similarity with the target resulted in a low precision score

A novel Bezier curve control point search algorithm for autonomous navigation using N-order polynomial search with boundary conditions

The study on path planning at intersections such as roundabouts has become a crucial aspect for autonomous vehicle development. This is due to the nature of the intersections, which can vary depending on the level of complexity. Path generation for an autonomous vehicle in a roundabout cornering is done using different curve fitting methods such as clothoid curves, Bezier curves, etc. However, the Bezier curve is the most widely used in the curve fitting algorithm for vehicle path planning as it can generate a possible number of path maneuvers. However, the main challenge when using the Bezier curve fitting algorithm is finding its control points. The control points are a crucial part of Bezier curve generation as it determines the curvature and shape of the curve. Therefore, a new technique for finding the control points of a Bezier curve is presented in this paper. The process starts with random points selection along the path. Specific random points will be selected through which the curve should pass through. The algorithm then expands the generalized Bezier curve equations to solve the mathematical problem and eventually, the simultaneous equation will be formed for the control point generation. The generated control points will be able to generate a proper Bezier curve that passes through all the selected points along the path. The generated equations are further validated in a test case study to show the effectiveness of the proposed method. This method is able to generate the desired Bezier curve through the selected points. This will open possibilities to generate a smoother predictive motion output using the Bezier curve fitting technique