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This study explores the potential of the natural and cost-effective method of wound healing using Alternanthera sessilis by an in vitro study (using fibroblast L929 cells). Gram-positive bacteria Staphylococcus aureus shows a zone of inhibition of 20 mm at 60 µg concentration in the antibiogram profile against the zinc oxide nanoparticles (ZnONPs) wetted in fabrics synthesized from the Amaranthaceae family. Through characterization studies of the AS-ZnONPs, it was found that UV–visible spectra show a peak in the range of 350–460 nm, Fourier transform infrared spectroscopy spectra show a correlation peak in the range of 340–4,500 cm−1, scanning electron microscope with electron diffraction analysis results in a peak in the range of 7.8–9.4, and high-resolution transmission electron microscope, which exposes the morphological character (diamond shape in a black and white background), shows a peak at 200 nm. This work shows that the leaf extract of A. sessilis might support the ancient method of wound healing.

Parallelism to the ala-tragus line is commonly used as a guide for the orientation of the occlusal plane with the help of a fox plane. The accuracy of parallelism is affected by improper judgment or patient movement. This report describes a method with a modified fox plane that aids in occlusal plane determination. The device is placed in the patient's mouth with the maxillary occlusal rim to determine parallelism to the ala-tragus line and interpupillary line. The adjustments are made until the laser light on the device runs parallel to the ala-tragus line, and the spirit bubble is centered between the lines of the tube. This technique facilitates direct visualization of parallelism, thereby avoiding parallax errors.

The design of PV-based high gain SEPIC converter integrated with four-switch strategy, which has been used to achieve sensorless speed control of Permanent magnet Brushless DC motor (PMBLDC) is analysed in this work. Hence SEPIC converter coupled with Fuzzy Logic, MPPT Algorithm is employed to retain voltage. SEPIC converter is chosen as it has a continuous current operation with high gain; Fuzzy MPPT algorithm is used as it provides accurate results faster while the classical MPPT techniques provide the results with fluctuations in attaining the maximum power. Regarding the sensorless control of PMBLDC motor, the conventional six-switch strategy is replaced by four-switch strategy and the sensors are replaced by back EMF method. Four-switch strategy has the capability of reducing the losses, size, cost and complexity of control. For achieving the nominal speed, a closed-loop control is implemented with PI controller, which is tuned by GWO technique. The proposed methodology is more efficient as the motor speed remains unchanged even under the full load condition. The end result of traditional PI algorithm and PI algorithm, which have been tuned by GWO algorithm, is compared and simulated through MATLAB. This is also implemented and validated in hardware by FPGA Spartan 6E controller.

Background: Assessing the difficulty level of the airway for intubation is extremely important in anaesthetic practice to avoid delays in intubation and resulting adverse consequences. Multiple grading systems are used by anaesthesiologists across the globe to aid in classifying the airways, but the number of studies assessing the level of agreement between various methods is scarce. Hence, the current study was conducted with an objective of assessing the level of agreement of Modified Mallampatti score (MMS) with Cormack-Lehane scoring and POGO Scoring. Materials and methods: The study was a cross sectional study, conducted in the Department of Anesthesiology, Government Mohan Kumaramangalam Medical College and Hospital, Salem, Tamil Nadu on adults aged between 18 to 65 years, belonging to ASA grade 1 and 2, scheduled for elective and emergency surgery under general anaesthesia. Patients with apparent restriction of mouth opening due to pain, with fresh facial injuries and dental abnormalities were excluded from the study. The airway of each subject was assessed by the trained anesthetist, in charge of the procedure. The agreement between the different methods of grading was assessed by kappa Statistic along with its standard error and P value. P value < 0.05 was considered as statistically significant. Results: A total of 236 subjects were included in the study. Among the study population, 74 (31.36%) had mallampatti grade I. The number of mallampatti grade II, III, and IV was 140 (59.32%), 21 (8.90%) and 1 (0.42%) respectively. Among the study population, 143 (60.59%) had Cormack Lehane grade I. The number of Cormack Lehane grade II, and III was 84 (35.59%), and 9 (3.81%) respectively. Among the study population, 170 (72.03%) had POGO grade 1. The number of POGO grade 2, 3 and 4 was 42 (17.80%), 15 (6.36%), and 9 (3.81%) respectively. The measure of agreement was very poor between Mallampatti grading with Cormack Lehane grading. (kappa statistics value-0.103, P value 0.032). The measure of agreement was also very poor between Mallampatti grading and POGO grade. (kappa statistics value was 0.105, P value 0.004). The measure of agreement was fair between Cormack Lehane grading and Mallampatti grading. (kappa statistics value was 0.327, P value <0.001). Conclusions: When compared to POGO score, Cormack Lehane grading had shown a better level of agreement with Mallampatti grading. But the level of agreement between any of the two methods was too low to rely on them interchangeably in clinical practice. [ABSTRACT FROM AUTHOR]

Double diffusive convection (DDC) flows are widely seen in many industrial processes where the thermo-solutal buoyancy forces generates vorticity and initiates convective heat and mass transfer. In this paper numerical computations are conducted on this behaviour inside cavities of different aspect ratio at nominal Rayleigh number using a finite element based code. Velocity -vorticity form of Navier-Stokes equations are solved along with energy and solutal concentration conservation equations simultaneously using Galerkin's weighted residual method. Bottom wall is assumed hot and salted while top wall is maintained as sink, both side walls of the cavity are assumed to be adiabatic to heat and mass flow. Generally cavities with the present boundary conditions exhibit weak vorticity and convection characteristic especially at low Rayleigh number. In this numerical work an attempt is made to explore the role of variation in relative strength of thermal and solutal buoyancy forces on flow characteristics and mode of heat and mass transfer in such conditions. Simulation results have been reported for different buoyancy ratios in the range -2≤N≤2, Rayleigh number varying from 1.0e5 to 1.0e3, for cavities of aspect ratios, 0.5(shallow), 1 (square) and 2 (deep). Flow contours are well validated with the results in the literature. The fluid rotation patterns are captured and reported under different operating conditions chosen, the vorticity generation is observed relatively low for deep cavity when compared to other two. Investigations revealed that fluid convection gets greatly hampered when operated in negative buoyancy ratio regime and require relatively higher Rayleigh number to change the mode of heat transfer from diffusion to convection. [ABSTRACT FROM AUTHOR]

The new organic 2-amino-5-chloropyridinium phenoxyacetate (2A5CPA) nonlinear optical (NLO) crystal was synthesized and grown from methanol solvent by slow evaporation method successfully. The complete 2A5CPA crystal structure was solved by single crystal XRD analysis and it indicates that the 2A5CPA crystal belongs to the tetragonal crystal system with the space group P41212. From the structure, the possible hydrogen bonding interactions have been analyzed. The presence of distinctive functional peaks in the 2A5CPA crystal was affirmed by FTIR analysis. The optical investigation reveals that the crystal was completely transparent in the UV–Vis–NIR region. The TG-DTA investigation assured that the 2A5CPA compound is thermally stable up to 134°C without any decomposition. The sharp endo thermic peak at 205°C in the DTA trace indicates the melting point of the crystal. The broad emissive band at 382 nm implies the violet emission characteristics of the 2A5CPA crystal. The dielectric study of the 2A5CPA crystal portrays the normal behavior to that of optical materials. The high work-hardening coefficient of 2.94 indicates the soft material nature of the crystal. The LDT value of the 2A5CPA crystal is estimated as 0.6135 GW/cm2. The third-order NLO properties of the 2A5CPA crystal were analyzed through Z-Scan experiment. [ABSTRACT FROM AUTHOR]

Introduction: The effect and stress distribution of rigid and non-rigid connectors were evaluated on a 5-unit fixed partial denture (FPD) with an implant as pier abutment by finite element analysis. Materials and Methods: A three-dimensional (3D) computed tomography with Digital imaging and communications in medicine (DICOM) format output was made for a patient with the implant in the second pre-molar region of the maxilla and missing the first pre-molar and first molar. In the obtained 3D finite element method (FEM) model, the implant in the second pre-molar region acts as a pier abutment. The canine and second molar served as terminal natural teeth abutments. By using CATIA V.05, the features of the implant in the second pre-molar region of 13 mm length and 3.75-mm diameter and 5 unit FPD tooth implant-supported prosthesis with rigid and non-rigid connector FEM models were made with a static vertical occlusal load of 250N. The areas and locations of maximum and minimum concentration of stress were analysed using Von Mises stress values for all the models at 10 Mpa. Results: The analysis of the von mishes stress values exposed the maximum stress concentrations at the load areas of all models. For all models, the highest stress values were located at connectors and cervical regions of abutment teeth, especially at the pier abutment. Conclusion: The area of maximum stress concentration at the pier abutment was decreased using the non-rigid connector at the mesial surface of the pier abutment.

Rehabilitation of facial disfigurement after a surgery or trauma is difficult to address as it involves individuality of the patient. Face being the visual pro forma, rehabilitating it is always a challenging task. This is predominantly due to the presence of soft tissue, lack of anatomic undercut, and increased muscle activity. The use of osseointegrated implants provides the most reliable retention, however, placing it on an intact facial defect further complicates rehabilitation. This case report is about rehabilitation of lost facial feature after tumor resection surgery.

In this paper, single-term Walsh series (STWS) method is applied to obtain the numerical solutions of Hammerstein systems of nonlinear Volterra integral equations of second kind (HSNVIES). Using the properties of the STWS method, HSNVIES can be easily converted into solvable recursive system of algebraic equations. Solutions obtained from the recursive system of algebraic equations are the solutions of the HSNVIES. Illustrative examples are provided with numerical solutions and the efficiency of this STWS method is also compared with the existing methods. [ABSTRACT FROM AUTHOR]

This paper discusses the performance of a solar assisted ground source heat pump (SAGSHP) system used for storage of solar energy in day time and space heating at night. Experiments were conducted to estimate the effectiveness of solar energy storage under the ground using a U-tube ground heat exchanger by absorbing solar energy from 9 A.M. to 5 P.M. and utilize the stored energy during space heating in the night time from 7 P.M. to 3 A.M.. Using the experimental data, heat absorbed by the solar collector, heat injected into the ground, heat extracted from the ground and COP of the system have been computed. Results indicate that heat absorption by the solar collector varied from 2.07 to 2.56 kW with increase in mass flow rate. Due to heat losses, only 1.991–2.414 kW of solar heat could be injected into the ground in the day time. Increase in mass flow rate of heat transfer fluid in the collector and ground heat exchanger has resulted in 21% increase in heat injection into the ground. Due to charging of ground, thermal energy of 2.8–3.2 times the work input to the solar collector could be extracted additionally from the ground in the night time for space heating. Charging of ground has resulted in 23% increase in the COP of the system for space heating in the night time. [ABSTRACT FROM AUTHOR]