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Frictional properties of sliding surfaces have practical importance in a variety of applications. Therefore, the present study investigates the ageing or holding time-dependent static friction of a wet granular layer using a slide-free-slide (SFS) friction test. It is observed that the static friction varies as a logarithm of hold time. Further, the Mohr–Coulombs' law of friction is used to determine adhesive friction and normal stress-dependent friction. The scaling law analysis has shown that the exponent of adhesive friction is more prominent in magnitude than the corresponding coefficient of friction. A static friction model, based on the formation and rupture of capillary bridges, has also been proposed for predicting the peaks of static friction at different hold times. At the end, the power laws, which correlate the number of attached capillary bridges and adhesion constant with hold time, are proposed to justify the present results. [ABSTRACT FROM AUTHOR]

Herein, two‐dimensional (2D) carbon nanosheets derived from biomass precursor is successfully synthesized via a cost‐effective salt‐templated process. Microstructural characterization and Raman spectral analysis of the sample derived from the salt template method reveals the formation of carbon nanosheets. The nanosheet thickness and its capacitance have been altered by varying the carbon precursor to salt‐template ratio. From the AFM data, the thickness of the as‐prepared thin carbon sheet was measured as ~5.16 nm, and the other thicker carbon sheet thickness was determined to be between 24 and 38 nm. The Brunauer Emmett Teller (BET) analysis shows that the thinner nanosheets possess a high specific surface area (SSA) of 485 m2 g−1, with slit‐pore geometry having a total pore volume of 0.29 cm3 g−1. Hence, compared to thicker carbon nanosheets (63.6 F g−1), the thinner carbon nanosheets exhibit superior electrochemical capacitance of 146 F g−1 in an aqueous 6 M KOH electrolyte, without employing any chemical activation. The electrochemical series resistance of as‐prepared carbon nanosheet samples was found to be <1 Ω with charge transfer resistances in the range of 0.29 Ω (thicker sheets) to 0.18 Ω (thinner sheets). The specific capacitance and electrochemical properties vary significantly when the nanosheet thickness has been tuned from thicker to thinner by altering the starch ratio in NaCl. The two‐electrode cell assembled using thinner carbon nanosheets exhibited the capacitance of 70.1 F g−1 with energy and power densities as 9.7 Wh kg−1 and 20 kW kg−1 respectively. [ABSTRACT FROM AUTHOR]

Prediction of static friction at sliding surfaces is having both fundamental and practical importance. In this article, a friction model was used to predict the static friction of wet granular material on hard surface. The model is based on the fact that granular particulates form capillary bridges to adhere with substrate, and rupture of these bridges results in friction. The model also considers the frictional strength of bridges, which develop during the application of shear velocity on sliding mass. The friction model is, in turn, validated with the experimental data of static friction vs. shear velocity of wet granular layers on a smooth rock surface. Scaling laws of frictional properties are also developed using regression analysis to justify the friction model. [ABSTRACT FROM AUTHOR]

Background: Epilepsy carries a lifetime risk of seizure-related accidents. The risk varies according to the socioeconomic profile of a place. Sufficient data is lacking for epilepsy-related accidents in the pediatric population.Objective: We aimed to identify the proportion of pediatric epileptic patients who met with accidents and their associated factors.Methods: A prospective study was done. Patients of less than 18 years with epilepsy of more than 1-year duration were included and were given a questionnaire modified for the pediatric population. The demography of accidents during seizures and drugs taken were recorded.Results: 135 epileptic children were included. 70.4% of patients suffered seizure-related accidents ranging from 1-10 accidents in their epilepsy duration. Falls (83.15%) were the most common, 25.26% of them required hospitalization. Accidents due to missing of drug dosage were observed in 23% patients.Conclusion: Seizure-related accidents are common in the pediatric population, and may lead to major accidents. Better epilepsy management with extra care for high-risk epilepsy patients may decrease their incidents. [ABSTRACT FROM AUTHOR]

Granular materials are a system of discrete particulates found practically in a variety of applications. Gouge particles along earthquake faults and rock joints behave as a granular material. In this article, the frictional properties of a wet granular layer are studied experimentally on a rock surface. Slide–hold–slide (SHS) tests show that static, steady, and residual stresses of the wet layer depend on the shear rate for a fixed hold time. Using Coulomb's law of friction, adhesive stress and coefficient of friction are determined for all three stresses. Both components of friction are found to increase with shear rate. A friction model for soft solids is used to predict static friction of the granular layer. The scaling laws are also proposed for static friction concerning chain density, relaxation time, and extension of the molecular chains in terms of normal stress, and these results are justified. [ABSTRACT FROM AUTHOR]

Summary: The present investigation reports the synthesis of Carbon Aerogel (CA) with varying pore size and surface area by changing the initial precursor that is, Resorcinol (R) and novel Catalyst (triethyl amine [TEA]) (C) ratio (R/C). The catalyst, TEA allows the gel to dry with negligible shrinkage. The R/C ratio has been kept 1000, 2000 and 3000. The CA with R/C = 1000 has the lowest pore size 1.93 nm, the highest surface area (369.14 m2/g) and the highest CO2 uptake of 24.40 wt.% (5.54 mmol/) at 40 atm CO2 pressure. The activated version of optimum CA (R/C = 1000) has been found to have an average pore diameter ~ 1.91 nm and CO2 uptake capacity of 29.56 wt% (6.71 mmol/g) at 25°C which is one of the highest CO2 storage capacity of CAs reported so far. Thus, the present manuscript put forward highly efficient and tunable CAs for enhanced CO2 storage. [ABSTRACT FROM AUTHOR]

The present study deals with the material tailoring of Mg(NH2)2–2LiH through dual borohydrides: the reactive LiBH4 and the non-reactive NaBH4. Furthermore, a pulverizer, as well as a catalyst FeTi, has been added in order to facilitate hydrogen sorption. Addition of LiBH4 to LiNH2 in a 1 : 3 molar ratio leads to the formation of Li4(BH4)(NH2)3 which also acts as a catalyst. However, the addition of NaBH4 doesn't lead to any compound formation but shows a catalytic effect. The onset dehydrogenation temperature of thermally treated Mg(NH2)2–2LiH/(Li4(BH4)(NH2)3–NaBH4) is 142 °C as against 196 °C for the basic material Mg(NH2)2–2LiH. However, with the FeTi catalyzed Mg(NH2)2–2LiH/(Li4(BH4)(NH2)3–NaBH4, it has been reduced to 120 °C. This is better than other similar amide/hydride composites where it is 149 °C (when the basic material is catalyzed with LiBH4). The FeTi catalyzed Mg(NH2)2–2LiH/(Li4(BH4)(NH2)3–NaBH4 sample shows better de/re-hydrogenation kinetics as it desorbs 3.9 ± 0.04 wt% and absorbs nearly 4.1 ± 0.04 wt% both within 30 min at 170 °C (with the H2 pressure being 0.1 MPa for desorption and 7 MPa for absorption). The eventual hydrogen storage capacity of Mg(NH2)2–2LiH/(Li4(BH4)(NH2)3–NaBH4 together with FeTi has been found to be ∼5.0 wt%. To make the effect of catalysts intelligible, we have put forward in a schematic way the role of Li and Na borohydrides with FeTi for improving the hydrogen sorption properties of Mg(NH2)2–2LiH. [ABSTRACT FROM AUTHOR]

Objective: To systematically study the pattern of medico-legal cases (MLC) undergoing radiological investigations and to quantify the burden of MLC’s. Materials and method: In this retrospective study carried out in our institution between January 2009 and May 2017, all the MLC’s details regarding nature of investigation, date, time, age, part examined, pattern of injury etc were manually collected and studied. Data was also collected for the time consumed by radiologists in carrying out MLC related activity. Results: The total of 1629 Medico legal radiological investigations (MLRI) were done. Age range of MLCs was 1 to 90 years (mean 35 years, S.D 15 years) with males accounting for 71.5% and females for 28.5% cases. Radiographs comprised bulk of investigations (N=1301, 79.8 %), followed by CT (N=272, 16.7 %) and Ultrasound (MLU) (N=56, 3.4%). Fracture was the most common abnormality (N=251, 83.6%). Total time spent in delivering court evidences by radiologists in the study duration was 757 days. Conclusions: Health institutions deal with substantial number of radiological MLC’s with average of approximately MLRI 192 per year. Vast majority of the abnormal investigations are Radiographs and fracture is commonest abnormality detected. The average number of days devoted to MLC work by radiologists is 90 per year. [ABSTRACT FROM AUTHOR]

Introduction: Femoral neck anteversion is an important parameter of proximal femoral geometry. It has not only an anthropological value but also it gives an insight into possible underlying hip pathology. Aim: To measure femoral neck anteversion values in sub himalyan population of north west India using digital radiography and dry bone measurements. Materials and Methods: This was a prospective hospital based study. Anteversion in 89 patients (89 paired femora) was measured by digital radiography and dry bone measurements. 93 unpaired dry cadaveric bones from the collection of bones maintained by Department of Anatomy of our institute were analysed by direct measurements. The results obtained were statistically analysed. Results: The mean femoral neck anteversion by digital radiography method was 14.70±2.26 while 14.57±2.67 by dry bone measurements. Males had higher anteversion values when compared to females in both groups. All these differences were not statistically significant. Conclusion: Increased femoral anteversion values are associated with clinical conditions like intoeing gait, hip osteoarthritis, femoroacetabular impingment, Developemental dysplasia of hip and Perthes disease. The data from this study would help establish values of femoral neck anteversion for sub himalayan population of north west India, provide insight into above mentioned disease conditions and help in planning orthopaedic surgeries like osteotomies about the hip and total hip replacement. [ABSTRACT FROM AUTHOR]

Background: Femoral neck-shaft angle is an important parameter of proximal femoral geometry. Not only it has an anthropological value but also it gives an insight into possible underlying hip pathology. The present study was conducted with an aim to find femoral neck-shaft angle values in subHimalayan population of Northwest India, and to measure the neck-shaft angle of proximal femur in both gender types using two different methods. Materials and Methods: This study was carried out to determine the average femoral neck-shaft angle in subHimalayan population of Northwest India. Neck-shaft angle in 89 femora was measured by digital radiography using PACS software while 93 dry bones were analyzed by direct measurements. The results obtained were statistically analyzed. Results: The results were analyzed using SPSS software. The mean femoral neck-shaft angle using digital radiography method was 127.45 ± 2.50 when compared to dry bone group 126.90 ± 2.50. Gender-wise males had higher neck-shaft angle values when compared to females in both groups and were statistically nonsignificant. Conclusion: Any increase or decrease in the angle of femoral neck-shaft angle is associated with various clinical conditions. Data from this study would help to establish values for subHimalayan population of Northwest India, provide insight into various associated disease conditions, and also serve as guidelines for manufacturing of orthopedic implants. [ABSTRACT FROM AUTHOR]

The present investigation describes the synergistic role of Li4(BH4)(NH2)3 and ZrFe2 in the hydrogen storage behaviour of a Li–Mg–N–H hydride system. The onset desorption temperature of ZrFe2-catalysed Mg(NH2)2–LiH–Li4(BH4)(NH2)3 is ∼122 °C, which is 83 °C, 63 °C, and 28 °C lower than that of thermally treated 2LiNH2–1MgH2, 2LiNH2–1MgH2–4 wt%ZrFe2, and 2LiNH2–1MgH2–0.1LiBH4 composites, respectively. Native Mg(NH2)2–LiH–Li4(BH4)(NH2)3 absorbed only 2.78 wt% of H2 within 30 min. On the other hand, the ZrFe2-catalysed Mg(NH2)2–LiH–Li4(BH4)(NH2)3 sample absorbed 3.70 wt% of hydrogen within 30 min and 5 wt% of H2 in 6 h at 180 °C and 7 MPa H2 pressure. Mg(NH2)2–LiH–Li4(BH4)(NH2)3 catalyzed with ZrFe2 shows negligible degradation of the storage capacity even after repeated cycles of de/rehydrogenation. The effect of ZrFe2 and Li4(BH4)(NH2)3 on a Mg(NH2)2/LiH composite has been described and discussed with the help of structural (X-ray diffraction), microstructural (electron microscopy), and vibrational modes of molecules through FTIR studies. The present results suggest that an optimum catalysis may originate from the synergistic action of an in situ formed quaternary hydride (Li4(BH4)(NH2)3) and an intermetallic-like ZrFe2, which acts as a pulverizer cum catalyst. [ABSTRACT FROM AUTHOR]

Background: Fractures of mid-face were first described by Le Fort and are classified into three categories - Le Fort I, Le Fort II and Le Fort III. The pterygoid processes of the sphenoid bone are fractured in all the three categories of Le Fort fractures as the sphenoid bone connects the cranium vault to the facial bones. Fractures of the pterygoid processes without associated Le Fort fractures are rare and are usually associated with fractures of the mandible, temporal bone or other facial bones. An isolated fracture of pterygoid plates without associated Le Fort fractures or fractures of other midface bones are exceedingly rare. Case Report: We present a case of an isolated fracture of the right lateral pterygoid plate by a penetrating foreign body (wooden twig) in an adult male who presented with discharging sinus in the oropharynx. The presence of the foreign body was confirmed on computed tomography and was removed under general anesthesia via submandibular incision. The patient had an uneventful postoperative hospital stay and was asymptomatic on a follow-up five months later. Conclusions: This article emphasizes the fact that pterygoid plates may be fractured without an associated Le Fort fracture or a fracture of the mandible. This is the first case of an isolated pterygoid plate fracture in the literature. [ABSTRACT FROM AUTHOR]

The present investigation describes the hydrogen sorption (de/absorption) behavior of MgH2 catalyzed by graphene sheet templated Fe3O4 nanoparticles (Fe3O4@GS). Hydrogen sorption studies reveal that MgH2 catalyzed by Fe3O4@GS (MgH2:Fe3O4@GS) offers improved hydrogen storage behavior as compared to stand-alone MgH2 catalyzed by graphene sheets (GS) (MgH2:GS) or Fe3O4 nanoparticles (MgH2:Fe3O4). The MgH2:Fe3O4@GS has an onset desorption temperature of ∼262 °C (∼142 °C lower than pristine MgH2), while MgH2:GS and MgH2:Fe3O4 have onset desorption temperatures of ∼275 °C and ∼298 °C respectively. In contrast to this, MgH2:GS absorbs 4.40 wt% and MgH2:Fe3O4 absorbs 5.50 wt% in 2.50 minutes at 290 °C under 15 atm hydrogen pressure. On the other hand, MgH2:Fe3O4@GS absorbs 6.20 wt% hydrogen in 2.50 minutes (which is considerably higher than recently studied catalyzed MgH2 systems) under identical temperature and pressure conditions. The MgH2 catalyzed with Fe3O4@GS shows negligible degradation of the storage capacity even after 25 cycles. Additionally, the desorption activation energy for MgH2:Fe3O4@GS has been found to be 90.53 kJ mol−1 (which is considerably lower as compared to metal/metal oxide catalyzed MgH2 and fluorographene catalyzed MgH2). The formation enthalpy for MgH2:Fe3O4@GS is 60.62 kJ per mole of H2 (13.44 kJ mol−1 lower than bulk MgH2). The catalytic effect of Fe3O4@GS has been described and discussed with the help of structural (X-ray diffraction (XRD)), micro structural (electron microscopy) and Raman spectroscopic studies. [ABSTRACT FROM AUTHOR]

Population explosion is one of the most critical problems of the world especially in developing countries like India. However, several contraceptive measures have been used to check birth rate since a long back. There are several types of contraceptive are available to control fertility in females, while there are a few options are available for males barrier, surgical and natural. About 90% of the world's contraceptive accesses by womens. Although, there are several misconceptions and religions barriers that's why the available contraceptives prevalence not access fully. There are several side effects of oral, surgical and other types of contraceptives have been also reported. Therefore, it becomes necessary to develop a biologically active substances or fertility regulating agents from plants which are economically, eco friendly and interfere with the fertility. Currently herbal contraception gain main focus in modern contraceptive research. Herbs have been used by women since the beginning of contraceptives. The development of new fertility regulating drug from medicinal plants is an attractive proposition, because from times immemorial humans have relied on plants and their products as sources of drugs and therapeutic agents. [ABSTRACT FROM AUTHOR]

Plants have been used as a source of contraceptive agents to control fertility by human being to check population and maintain sustainable development. Ayurvedic literature reveals that since time immemorial man used plants to control fertility as a birth controlling methods. The plants have been explored to control fertility or abortion includes Carrica papya, Cassia occidentalis, Citullus colocynthis Daucus carota, Gossypium herbaceum etc. Several workers have been reported antifertility activities of medicinal plants in male animals, intended to develop a safe, cheap, reversible male contraceptive agent. This review is an attempt to summarize some of the plants reporting fertility regulating effects with their part (s) used and types of extract. We survey from 2011 to 2014 and then include 24 plants and 10 of them are having been discussed in details of antifertility effects. [ABSTRACT FROM AUTHOR]