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The need for thin and highly deformable textile reinforcements is constant in sectors like thin composites, catching nets, and complex construction designs (like dome-shape). The conventional rectangular-patterned meshed wovens are used in thin composite structures as reinforcement at the commercial level. These woven textiles are bidirectional and exhibit approximately the same strength along both axes. However, these conventional rectangular-patterned mesh designs show poor impact stress distribution capacity. Interestingly, very thin and fine mesh designs are available in nature. One such example is the spider web structure. These structures have evolved with time and optimised their mesh pattern design for better impact damage resistance and load transfer. In this study, the basalt fibre reinforced mortar textile composites are considered for the investigation due to their growing interest in civil and construction applications. To demonstrate how the mesh geometry in textiles significantly influences the stress transfer, energy absorption, and deformation of reinforcements under various impact situations, three different geometries, (a) square shape mesh, (b) diamond-shaped mesh, and (c) bio-inspired spider web mesh, are modelled and meshed based on the reference geometry's meshing pattern and dimensions. The results of numerical simulations show that a meshed reinforcement design inspired by spider-orb-web has improved mechanical features compared to conventional square and diamond shape mesh designs under high velocity impact loading. [ABSTRACT FROM AUTHOR]

Low-velocity impact induced damage in symmetric and asymmetric laminates is analyzed. A generalized lay-up sequence is proposed for asymmetric laminate. Asymmetric laminate fabricated according to the proposed lay-up sequence have its stiffness characteristic almost identical to those of a symmetric laminates. Proposed lay-up sequence provides a laminate which have zero bending-extension coupling and behaves as quasi-isotropic laminate. A cylindrical impactor with hemispherical nose having mass 5.23 kg is impacted with a velocity of 3 ms−1, 4 ms−1, and 6 ms−1. Damage pattern and energy–time relation of proposed asymmetric laminate are compared with symmetric laminate having similar stiffness matrices. Energy absorbed by proposed quasi-isotropic asymmetric and symmetric laminate is also compared with laminate of different stacking sequence proposed by various researchers. Numerical analysis is done by commercially available software LS-DYNA. [ABSTRACT FROM AUTHOR]

In recent decades fiber-reinforced polymer (FRP) materials have revolutionized the world of engineering material. It has emerged as a substitute to traditional engineering material because of its aspect ratio. The increase in demand of FRP in various areas such as automotive and aerospace increases the need to do deep and diversified impact analysis of FRP composites. This article is an attempt to review literatures on the impact analysis of FRP composite validated by LS-DYNA. The effect of projectile characterization, fiber orientation, and cores on the impact behavior of FRP composite has been discussed. An attempt is done to view literature from 1990s to present days. Because of insufficiency of relevant paper (using LS-DYNA) in 1990s, this review article includes work done from 2000s to present days. Temperature dependency, energy absorbed, contact time, and damage pattern of the FRP laminates, along with future trend of research work in the area of composite are also discussed. POLYM. COMPOS., 36:1786-1798, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Background: Time since death (TSD) is an important parameter to the forensic expert. Only a fewer studies are available in the literature to determine the relationship between vitreous K + concentration and TSD especially among injury (trauma) cases and thus information on the same is patchy and scanty. Objective: To determine the relationship between changes in vitreous K+ concentration with increasing TSD among injury (trauma) cases. An additional objective was to derive a formula for determining TSD from changes in levels of vitreous K+ in the study subjects. Materials and Methods: In this study, autopsy cases brought to the mortuary of Department of Forensic Medicine and Toxicology of a tertiary care center, were the subjected for collection of vitreous humor for determination of vitreous potassium. Data of 55 such cases where autopsy confirmed the cause of death as injury (trauma), were included in this study. Determination of potassium level in the collected sample was done using ion-selective electrode method (Biolyte 2000 auto analyzer). Results: A linear relationship was observed between vitreous potassium concentration and TSD in both the eyes. External factors like seasonal variations and temperature, gender difference and age had no appreciable effect on the concentration of vitreous potassium in either eye. In this study, the linear regression equations obtained from potassium concentration (y) verses time (x) for the two groups among injury (trauma) cases were as follows: For right eye: Regression line (y) = -5.040 (x) = +1.989, for left eye: Regression line (y) = -5.223 (x) = +2.005. The potassium levels are found to increase up to 40 h after death. Conclusion: The study highlighted the usefulness of relationship between vitreous potassium concentration and TSD in both the eyes. The formula calculated from the current study could prove to be more appropriate as it is based on a more recent study and more reliable tests. [ABSTRACT FROM AUTHOR]

Context: Traffic policemen are at an increased risk of suffering from hazards of noise pollution because they are engaged in controlling traffic noise, particularly at heavy traffic junctions. The effect is more in this subgroup because they are continuously exposed to it. Aim: The present study was aimed at assessing the knowledge, attitude and practices of traffic policemen regarding auditory effects of traffic noise pollution in Ambala city. Settings and Design: Cross-sectional workplace survey. Materials and Methods: The present descriptive study was carried out in different traffic zones of Ambala city during April-June 2013. The study population consisted of 100 traffic policemen working in different traffic intersections of Ambala city. Statistical Analysis Used: Structured interview schedule was used to collect the data. SPSS version 17.0 was used for analysis. Interpretation of data was performed using percentages and proportions. Results: Majority (75%) of the study subjects were exposed to traffic noise pollution for more than 5 years. Of the total subjects, 5% of respondents reported below-average hearing on self-assessment of hearing ability. Seventeen percent of the study population accepted that while hearing over phone they do miss some conversation. Most (98%) of the traffic police did not use any personal protective equipment (PPEs) like earplugs/earmuffs, and the non-availability of these PPEs (90%) is the common reason for the hearing loss. Conclusions: The study concludes that traffic policemen are not much aware regarding impending auditory effects of traffic noise pollution. Duty rotation, duty scheduling and other forms of preventive modalities for exposure limitation are suggested. [ABSTRACT FROM AUTHOR]

We report a case of brucellosis in a patient infected with the human immunodeficiency virus (HIV), who came to seek medical care at a tertiary care center in rural Uttar Pradesh. A 26-year-old male patient, milk salesperson by occupation who also used to rear his cattle as a routine, presented with complaints of longstanding fever accompanied with vomiting, giddiness, myalgia, and headache. No significant abnormality was detected on routine physical and laboratory investigations except reactive HIV antibodies. It was decided to conduct the serological tests for the evidence of brucellosis as clinical symptoms continued to persist. He had high titers of Brucella agglutinin, and responded to treatment with tetracycline and streptomycin. The isolates were confirmed at Indian Veterinary Research Institute, Izatnagar. [ABSTRACT FROM AUTHOR]

Present work deals with the numerical investigation of a cantilever beam having I cross section made up of piezoelectric material for its actuation capability. The beam is modeled under the assumption of Euler's Bernoulli equation. Eight cases are considered for different electrode locations. The beam was subjected to voltage loads at different locations. It was noticed that tip deflection increases with increasing applied voltage across the electrodes. Maximum tip deflection was achieved with the increase in voltage with particular electrode arrangement. In this report we have also demonstrated that for downward tip deflection, there are two values of thickness ratio of flange and web for a given tip deflection at a given applied voltage. [ABSTRACT FROM AUTHOR]

Background: Dermatophytosis has gained significant importance in recent years owing to increased incidence, more atypical lesions, changing mycological profile and growing antifungal resistance. Therefore, this study was planned to know the clinicomycological profile of dermatophytic infections in patients attending our tertiary care centre., Materials and Methods: A total of 700 patients with superficial fungal infections belonging to all age groups and both sexes were taken up for this cross-sectional study. Sociodemographic and clinical details were noted on a prestructured proforma. Superficial lesions were clinically examined and the sample was collected by appropriate collection methods. Direct microscopy by potassium hydroxide wet mount was done to see hyphae. For culture Sabouraud's dextrose agar (SDA) with chloramphenicol and cyclohexamide was used., Results: Dermatophytic infections were detected in 75.8% (531/700) patients. Young people belonging to age group of 21-30 years were commonly affected. Tinea corporis was the commonest clinical picture seen in 20% of the cases. Oral antifungals were taken by 33.1% and topical creams were used by 74.2% of the patients. Direct microscopy was positive in 91.3% and culture was positive for dermatophytes in 61% of the study subjects. T. mentagrophytes was the commonest dermatophyte isolated., Conclusion: Irrational use of topical steroids needs to be controlled. KOH microscopy can be useful as a point of care test for rapid screening of dermatophytic infections. Culture is necessary to differentiate various dermatophytes and to guide the antifungal treatment., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)