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Highlights • The Stochastic buckling behaviour of sandwich plates considering uncertain system parameters is presented based on the higher-order-zigzag theory (HOZT) coupled with an ANN assisted stochastic finite element model. • Individual and compound effect of stochasticity are analysed to demonstrate the importance of higher order buckling modes. • The probabilistic results show that a significant level of variation with respect to the deterministic values could occur due to the presence of inevitable source-uncertainty in the input parameters demonstrating the necessity of an inclusive design paradigm considering stochastic effects. Abstract The stochastic buckling behaviour of sandwich plates is presented considering uncertain system parameters (material and geometric uncertainty). The higher-order-zigzag theory (HOZT) coupled with stochastic finite element model is employed to evaluate the random first three buckling loads. A cubic in-plane displacement variation is considered for both face sheets and core while quadratic transverse displacement is considered within the core and assumed constant in the faces beyond the core. The global stiffness matrix is stored in a single array by using skyline technique and stochastic buckling equation is solved by simultaneous iteration technique. The individual as well as compound stochastic effect of ply-orientation angle, core thickness, face sheets thickness and material properties (both core and laminate) of sandwich plates are considered in this study. A significant level of computational efficiency is achieved by using artificial neural network (ANN) based surrogate model coupled with the finite element approach. Statistical analyses are carried out to illustrate the results of stochastic buckling behaviour. Normally in case of various engineering applications, the critical buckling load with the least Eigen value is deemed to be useful. However, the results presented in this paper demonstrate the importance of considering higher order buckling modes in case of a realistic stochastic analysis. Besides that, the probabilistic results for global stability behaviour of sandwich structures show that a significant level of variation with respect to the deterministic values could occur due to the presence of inevitable source-uncertainty in the input parameters demonstrating the requirement of an inclusive design paradigm considering stochastic effects. [ABSTRACT FROM AUTHOR]

Inhibition of carbohydrate digestion and modulation of glucose uptake are the major mechanisms of anti-hyperglycemic potential known to be played by phenolics; but the role of archaeologically relevant staple pearl millet (Pennisetum glaucum ; PM), is still much unknown. A combined approach using in vitro inhibitory data and in silico docking of PM phenolics against key players of glucose homeostasis (salivary α-amylase: SA; pancreatic α-amylase: PA; α-glucosidase, maltase-glucoamylase: MGAM and GLUT2) were carried out. Observed notable inhibition with HHB299 having the most relevant effect (IC 50 : 73.06 ± 0.37 μg/mL for α-amylase; IC 50 : 73.80 ± 0.12 μg/mL for α-glucosidase). The role of phenolics on basal glucose uptake into hepatocytes, revealed a maximum of 241.25% in PC612 and the least of 198.1% in HHB67imp. Virtual screening via docking found that 3, 4-Di-OMe luteolin, acacetin as the major flavonoids while salicylic acid, melilotic acid as the key phenolic acids contributing towards the observed anti-diabetic effect. Further, structure-activity relationship (SAR) identified the critical functional groups required for the protein-phenolic molecular interactions. This report validates the role of PM phenolics in inhibiting carbolytic enzymes and regulating GLUT and thus probes the link towards the anti-diabetic potential. • Anti-hyperglycemic potential of pearl millet, an archaeological staple is proposed. • In vitro inhibition, in silico docking and C14 glucose uptake validated the role. • Key phenolic types and their prerequisite for observed functionality were identified. [ABSTRACT FROM AUTHOR]

This paper quantifies the influence of uncertainty in the low-velocity impact responses of sandwich plates with composite face sheets considering the effects of obliqueness in impact angle and twist in the plate geometry. The stochastic impact analysis is conducted by using finite element (FE) modelling based on an eight nodded isoparametric quadratic plate bending element coupled with multivariate adaptive regression spline (MARS) in order to achieve computational efficiency. The modified Hertzian contact law is employed to model contact force and other impact parameters. Newmark's time integration scheme is used to solve the time-dependent equations. Comprehensive deterministic as well as probabilistic results are presented by considering the effects of location of impact, ply orientation angle, impactor velocity, impact angle, face-sheet material property, twist angle, plate thickness and mass of impactor. The relative importance of various input parameters is determined by conducting a sensitivity analysis. The results presented in this paper reveal that the impact responses of sandwich plates are significantly affected by the effect of source-uncertainty that in turn establishes the importance of adopting an inclusive stochastic design approach for impact modelling in sandwich plates. • The compound effect of source-uncertainty on low-velocity impact of sandwich plates with face sheets made of composite laminates is quantified following an efficient hybrid simulation approach (MARS-FE). • Probabilistic results leading to the complete probabilistic characterization of the impact response quantities are presented considering the critical effects of oblique impact and twist in plate geometry. • The importance of adopting an inclusive design paradigm considering the effect of source-uncertainties in the impact analysis of sandwich structures is established through the presented numerical results. • An assessment of relative sensitivity of the critical parameters is presented for the impact responses to ensure adequate quality control in the optimum design and manufacturing of sandwich structures prone to impact loading. [ABSTRACT FROM AUTHOR]

[Display omitted] • The paper introduces a new passive collector design for the purpose of light collection for daylighting. • Maintain uniform lighting levels for the most part of the day under clear sky sun. • The average illuminance of around 400 lx was observed on the floor of the experimental room for the most part of the day. • The performance of proposed designed collectors leads under the low-altitude sun when compared to conventional designs. A tubular skylight (TS) is an effective system for transporting natural sunlight into the building interiors. However, the passive nature of the system may not account for the changing orientation of the sun and the conventional daylight collector designs like transparent dome are less effective under low altitude sun. This paper focuses on the performance evaluation of specifically designed TS having rectilinear parabolic-profile reflectors integrated with plane surface reflectors and wedge-shaped prism for daylight collection. The designed configuration redirects the low altitude incident rays efficiently into a vertical mirror light pipe having a rectangular cross-section and aims at giving desired levels of lighting throughout the sunny day. Numerical analysis of the same was carried out for various sky conditions. Experimental results for the proposed TS design show improved lighting levels during the low-altitude sun and reduced but consistent lighting during the mid-day. Average illuminance of ~ 400 lx was observed on the floor of the experiment room for the most part of the day. Along with capturing beam sunlight a significant amount of diffuse daylight capturing ability under clear sky conditions is observed using the proposed TS. The average illuminance value obtained on the work plane during winter solstice through the most optimized configured TS was more than twice the lighting value achieved by a conventional daylight-collecting transparent dome and almost twice the lighting value achieved by a TS with a prismatic dome collector. Under overcast sky conditions, the performance of the proposed configuration of TS is at par. [ABSTRACT FROM AUTHOR]

Functionally graded materials, sandwich structures and composite laminates have been widely investigated individually in last few decades for their respective set of advantages over conventional monolithic structures. However, the tremendous recent advances in manufacturing processes have opened up new frontiers of research specifically to form hybrid structures for multifunctional applications, where the advantages of each of the constituting components could potentially be exploited in a single structure. Such complex hybrid structures are often susceptible to manufacturing uncertainties and different forms of variability. To characterize the stochastic dynamic behaviour of these hybrid structural forms in a comprehensive, practically-relevant, yet efficient framework, here we present a multi-physical probabilistic vibration analysis based on Gaussian Process Regression (GPR) assisted finite element (FE) approach coupled with Monte Carlo Simulation. Integration of the GPR based machine learning model with the physics based simulation model leads to a significant level of computational efficiency in the quantification of system uncertainty. In the stochastic approach for various hybrid structural configurations, the compound effects of source-uncertainties are considered in order to assess the effect of different critical multi-physical parameters systematically involving material, geometric and physical aspects. The numerical results categorically indicate that the source-uncertainty of hybrid shells with different geometries has a significant effect on dynamic behaviour of the structure, which makes it imperative to take into account such probabilistic deviations to ensure adequate operational safety and serviceability. [ABSTRACT FROM AUTHOR]

[Display omitted] • Illuminance patterns analysis on the various surfaces of a tubular daylight guidance system (TDGS). • TDGS comprises a parabolic profiled daylight collector with a prismatic cover sideways and a diffuser as the top. • Proposed design of TDGS results in a significant reduction in light concentration zones. • No compromise in the photometric light transmission. • Light distribution at the exit aperture of long-length mirror light pipe is relatively better. • Enhanced values of illuminance under low altitude beam sunlight and diffuse skylight. The illuminance patterns formed on the various surfaces of a tubular daylight guidance system (TDGS) were numerically measured and calculated for the beam sunlight input. For this study, the TDGS comprises a revolved parabolic profiled daylight collector geometry and a vertical MLP system for daylight guidance. TDGS is basically a non-imaging optical system that is designed to efficiently transmit available sunlight across the MLP (mirror light pipe) length. But while doing so the problematic hotspots are observed mainly on the diffuser placed at the exit aperture of cylindrical MLP which further results in non-uniform illumination in the daylit room. In this work, the use of a prismatic casing arranged sideways to the parabolic profiled collector and a sloped diffuser as a top cover shows a significant reduction in the hotspot problem on the exit aperture of MLP without compromising light transmission in TDGS. The 'non-uniformity' index value, I r signifying the ratio of maximum illuminance to average illuminance on the diffuser surface dropped considerably for the proposed design signifying an increase in uniformity on the exit aperture of MLP. For 1 m long MLP (aspect ratio = 2.5), the maximum value of I r was ∼ 19 and ∼ 37 for TDGS with dome collector and TDGS with parabolic collector having plane cover (TS A) respectively on midday timings of 21st June while for the proposed design the value was I r < 5. For 2 m long MLP (aspect ratio = 5), the value was I r < 4 much lower in comparison to I r of ∼ 20 and ∼ 36 for TS with dome collector and TS A respectively. A considerable decrease in the severity of hotspots was realized from the results. The proposed collector design was also tested for the illuminance values on the work plane of the simulated room under beam sunlight, diffuse skylight, and overcast sky conditions. No compromise in the average illuminance values was observed when compared to the parabolic collector with transparent casing. Moreover, the proposed design gave enhanced values of illuminance under low altitude beam sunlight as well as under diffuse skylight for various timings of the day. Performance under the overcast sky was found slightly lesser in comparison to conventional collector designs though nominal levels of illuminance were observed for all the configurations of collectors due to the very less magnitude of light availability. [ABSTRACT FROM AUTHOR]

Background Radical radiotherapy with 66–70 Gy in 33–35 fractions is the standard radiotherapy schedule in head and neck squamous cell carcinoma. Altered fractionation improves the therapeutic ratio compared to conventional radiotherapy. We did a phase 2b randomised trial to compare two radiotherapy schedules in patients undergoing radical radiotherapy in oral cancer. Methods This study was conducted in Thiruvananthapuram, India, from May 2013 to December 2014. 76 patients with squamous cell carcinoma of oral cavity intended to be treated with radical radiotherapy were randomised either to receive conventional radiotherapy (70 Gy in 35 fractions) or altered fractionation (52.5 Gy in 15 fractions). The primary endpoints were acute toxicity and response rate. Acute toxicity was evaluated weekly during treatment using RTOG toxicity criteria. Findings 38 patients were randomly assigned to each group. Two patients from the conventional group and four patients from the altered fractionation group were excluded from final analysis. Acute grade 2 skin toxicity was significantly more common in the conventional radiotherapy group than in the altered fractionation group (80.5% versus 2.9%; p = 0.0001). World Health Organisation (WHO) step III analgesics usage was significantly higher in the conventional group than in the altered fractionation group (52.7% versus 14.7%; p = 0.004). Complete response at 6 months was more common in the altered fractionation group than in the conventional group (91% versus 63.8%; p = 0.01). One-year disease free survival was higher in the altered fractionation group than in the conventional group (76.9% versus 54.7%; p = 0.0107). Overall survival data are pending. Interpretation Results favoured altered fractionation radiotherapy. Longer follow-up is needed to assess late toxicity and overall survival. A phase 3 trial is warranted. [ABSTRACT FROM AUTHOR]

Abstract: To assess microbiological quality of buffalo meat trimmings (TT=114) and silver sides (SS=41), samples were collected from four different Indian meat packing plants. The aim of this study was: (i) to evaluate standard plate count (SPC), psychrotrophic count (PTC), Enterococcus feacalis count (EFC), Staphylococcus aureus count (SAC) and Escherichia coli count (ECC) and the presence of Salmonella spp. and Listeria monocytogenes; and (ii) also to determine vero toxic E. coli (VTEC) by polymerase chain reaction (PCR). TT samples had significantly higher (P <0.001) SPC, PTC, EFC, and SAC than SS, while across the meat types there was no difference (P >0.05) in ECC. E. coli was recovered from 32.4% TT and 19.5% SS samples. The prevalence rate of Salmonella spp. and L. monocytogenes in TT was 1.75% and 0.87%, respectively. But no SS sample was found to be positive for any of these two pathogens. VTEC was found in 2.58% of all the tested samples. This finding suggests that TT contain higher microbes but only small numbers of pathogens of latent zoonotic importance. The present study confirmed the importance of maintaining good process hygiene at meat plants for microbiological status of buffalo meat. [Copyright &y& Elsevier]