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Rice-paddy agriculture is widely expanding, particularly in Asia. Rice-paddy fields are stagnated with water and insecticides are applied to control pests. Expansion of agriculture and pesticide are known drivers of declining amphibian populations globally. Yet, several amphibians persist in such temporary wetlands. How amphibians persist in this landscape matrix is not clearly understood. We document amphibian diversity in rice-paddy fields in south India and examine trophic interactions of the two most abundant species. From 60 rice paddy fields, we recorded six species of anurans among which, Minervarya caperata and Microhyla ornata were most abundant. The stomach contents of 57 individuals of the two species were extracted. They consumed prey items belonging to eight orders and 56 taxonomically distinct units dominated by Diptera and Hymenoptera: Formicidae. Although individuals of M. ornata were smaller in body size compared to M. caperata, both species consumed a similar number of arthropods. The dietary niche breadth of M. caperata was wider than M. ornata and the diets of the two species did not overlap greatly. We discuss our findings in the context of prey availability, foraging strategies, and highlight the role of anurans in pest control. [ABSTRACT FROM AUTHOR]

The article focuses on observing and documenting a predation event where a frog, identified as Raorchestes nerostagona (Kalpatta Yellow Bush Frog), was caught and consumed by a snake of the genus Dendrelaphis in Kadanoor, Coorg, Karnataka, India.

In recent times, several new species of amphibians have been described from India. Many of these discoveries are from biodiversity hotspots or from within protected areas. We undertook amphibian surveys in human dominated landscapes outside of protected areas in south western region of India between years 2013–2015. We encountered a new species of Microhyla which is described here as Microhyla laterite sp. nov. It was delimited using molecular, morphometric and bioacoustics comparisons. Microhyla laterite sp. nov. appears to be restricted to areas of the West coast of India dominated by laterite rock formations. The laterite rock formations date as far back as the Cretaceous-Tertiary boundary and are considered to be wastelands in-spite of their intriguing geological history. We identify knowledge gaps in our understanding of the genus Microhyla from the Indian subcontinent and suggest ways to bridge them. [ABSTRACT FROM AUTHOR]

A rigorous analytical thermal model has been formulated for the analysis of self-heating effects in FinFETs, under both steady-state and transient stress conditions. 3-D self-consistent electrothermal simulations, tuned with experimentally measured electrical characteristics, were used to understand the nature of self-heating in FinFETs and calibrate the proposed model. The accuracy of the model has been demonstrated for a wide range of multifin devices by comparing it against finite element simulations. The model has been applied to carry out a detailed sensitivity analysis of self-heating with respect to various FinFET parameters and structures, which are critical for improving circuit performance and electrical overstress/electrostatic discharge (ESD) reliability. The transient model has been used to estimate the thermal time constants of these devices and predict the sensitivity of power-to-failure to various device parameters, for both long and short pulse ESD situations. Suitable modifications to the model are also proposed for evaluating the thermal characteristics of production level FinFET (or Tri-gate FET) structures involving metal-gates, body-tied bulk FinFETs, and trench contacts. [ABSTRACT FROM PUBLISHER]

Geological and magnetic features were interpreted using IRS-P6 (LISS-III) and aeromagnetic data respectively. Historical rainfall data and the water-table fluctuations were also analysed and integrated with the above in conjunction with ground truth information. It is observed that the intrusion activity of the dykes had disturbed the fracture network, resulting in filling up of pore spaces in the weathered columns. Lineaments across the dykes, the associated pediment and the weathered pediplain have more porosity and permeability. The accumulation and rising of groundwater flow is influenced by the above structural set-up. It is concluded that significant amount of base flow had resulted in hydro-loading and was responsible for the micro-seismicity. [ABSTRACT FROM AUTHOR]

Anurans of Puducherry, a union territory measuring 293 km2, on the East coast of India are understudied. In this communication, we provide a comprehensive list of anurans encountered in and around wetlands across this union territory. Visual Encounter Surveys during the rainy season in 17 wetlands yielded a total of 14 species belonging to four families. This diversity is relatively low compared to other urban areas like Bangalore or Pune having 16 and 31 species respectively. Possible reasons for this low diversity and scope for future studies have been emphasized. [ABSTRACT FROM AUTHOR]

India has the largest population of patients with type 2 diabetes mellitus. The conventional agents used to treat type 2 diabetes frequently exhibit reduced efficacy over time leading to inadequate glycaemic control and are also associated with adverse effects. Hence, there is a need for alternative therapies that can overcome the limitations associated with conventional antidiabetic agents. This review focuses on Gliptins, which have become a research area of intense focus and present an alternative therapeutic strategy for patients with type 2 diabetes. Gliptins show significant improvements in glycaemic control and are well tolerated, particularly with regard to weight change and hypoglycemia. Hence, gliptins are considered as useful agents for the treatment of type 2 diabetes mellitus. [ABSTRACT FROM AUTHOR]

An activation-energy asymptotic theory is developed that predicts autoignition of condensed hydrocarbon fuels in non-premixed flows. Steady, laminar, stagnation-point flow of an oxidizer stream, toward the vaporizing surface of a liquid fuel is considered. The analysis is restricted to the case where the temperature of the oxidizer stream, T2, is greater than the normal boiling point of the liquid fuel. The gas-phase chemical reaction is described by a one-step overall process. The chemical-kinetic rate parameters are the activation temperature, Ta, and the frequency factor, B. A Zel'dovich number, β, is constructed that is proportional to the ratio Ta/T2. The analysis is performed in the asymptotic limit of large values of β. It predicts the value of the Damkohler number, at autoignition. The Damkohler number is defined as the ratio of a characteristic flow time to a characteristic chemical reaction time. The flow time is the reciprocal of the strain-rate, and the chemical time depends on the chemical-kinetic rate parameters. To illustrate the application of the results of the analysis, experiments are conducted in the counterflow configuration. Fuels tested are n-heptane, n-octane, n-decane, n-dodecane, n-hexadecane, iso-octane, cyclohexane, methylcyclohexane, o-xylene, JP-10, JP-8, and diesel. The temperature of the oxidizer stream at autoignition is measured for various values of the strain-rate. The strain-rate, and the value of the Damkohler number at autoignition, obtained from the analysis, are used to obtain the chemical-kinetic rate parameters, for the fuels tested here. Critical conditions of extinction of flames burning these liquid fuels are also measured. A key finding of this work is that for the straight-chain alkanes tested here, at a given value of the strain-rate, n-heptane is the most difficult to ignite, followed by n-octane, n-decane, n-dodecane, and n-hexadecane. The order is reversed for extinction; here it is found that flames burning n-heptane and n-octane are the most difficult to extinguish followed by n-decane, n-dodecane, and n-hexadecane. [ABSTRACT FROM AUTHOR]

Study on the cementation of the regenerated activity (from spent resin using ferric as regenerant) containing ferric in cement matrix showed that compressive strength and leaching behaviour are better when the ferric strength was < 5 N. The diffusion coefficient of Cs from the cement matrix was found to be in the range 2·4 x 10-5 cm²/day and 5·9 x 10-5 cm²/day with ferric solutions of strength in the range 0·5-3 N. When bentonite and vermiculite were included in the cement matrix, the diffusion coefficient of Cs was found to be in the range 6·2 x 10-7 cm²/day to 1·26 x 10-5 cm²/day with ferric strength in the same range. [ABSTRACT FROM AUTHOR]

Abstract: A rate-ratio asymptotic analysis is carried out to elucidate the mechanisms of autoignition of n-heptane (C7H16) in laminar, nonpremixed flows. It has been previously established that autoignition of n-heptane takes place in three distinct regimes. These regimes are called the low-temperature regime, the intermediate-temperature regime, and the high-temperature regime. The present analysis considers the high-temperature regime. A reduced chemical-kinetic mechanism made up of two global steps is used in the analysis. The reduced mechanism is deduced from a skeletal mechanism made up of 16 elementary reactions. The skeletal mechanism is derived from a short mechanism made up of 30 elementary reactions. The short mechanism is deduced from a detailed mechanism made up of 56 elementary reactions. In the reduced mechanism, the first global step represents a sequence of fast reactions starting from the rate-limiting elementary reaction between n-heptane and HO2. In this global step C7H16 is consumed and hydrogen peroxide (H2O2) is formed. The second global step represents a sequence of fast reactions starting from the rate-limiting elementary reaction in which H2O2 is consumed and OH is formed. A key aspect of the second global step is that the sequence of fast reactions gives rise to consumption of fuel only without net consumption of H2O2. This makes the chemical system autocatalytic. The unsteady flamelet equations are used to predict the onset of autoignition. In the flamelet equations a conserved scalar quantity, Z, is used as the independent variable. On the oxidizer side of the mixing layer , and on the fuel side . The practical case where the temperature of the oxidizer stream, , is much greater than the temperature of the fuel stream is considered. Therefore autoignition is presumed to take place close to . Balance equations are written for C7H16 and H2O2. It is postulated that autoignition will take place when the gradient of mass fraction fuel with respect to Z, evaluated at , is zero. The value of when autoignition takes place is obtained as a function of the strain rate. These critical conditions of autoignition obtained from asymptotic analysis agree well with those calculated using the detailed mechanism and the skeletal mechanism. [Copyright &y& Elsevier]

In our paper , there was an error in (50), which is rewritten here as [ABSTRACT FROM AUTHOR]

Of the goals and targets specified by the Kunming‐Montreal Global Biodiversity Framework, Target 3, often referred to as "30 × 30," has garnered widespread attention globally. In this paper, we critique India's potential to meet this target. We find that with its vast network of ecosystems that are under some form of protection and through the recognition of other effective area‐based conservation measures sites, India has the potential to meet the quantitative target of conserving and managing at least 30% of its area by 2030. However, the qualitative attributes of the target might be more difficult to realize owing to several challenges, such as inadequate landscape connectivity, insufficient representation of habitats in the current protected area model, and the exacerbation of socioeconomic vulnerabilities of resource‐dependent communities. To achieve strategic, inclusive, and equitable conservation, we suggest a four‐pronged approach involving landscape‐level biodiversity conservation, socially just and collaborative safeguarding of biodiversity, and relevant policy (re)formulation, informed and underlain by long‐term research and impact monitoring. Although we focus on India, the issues we discuss are of broader relevance, especially for countries across the Global South that are also likely to be significantly impacted by the implementation of the target. [ABSTRACT FROM AUTHOR]

The experiment was conducted to evaluate the nutrient utilization ability of sweet orange (Citrus sinensis L. Osbeck) budded on five rootstocks (viz., Sathgudi, Rangpur lime, Cleopatra mandarin, Troyer citrange, and Trifoliate orange) in Alfisols at the experimental farm of the Citrus Improvement Project, S. V. Agricultural College Farm, Tirupati, Andhra Pradesh, India. Results of the study revealed that all the five rootstocks showed differential behaviors in terms of nutrient absorption from the soil. Rootstocks exhibited significant variation in the leaf content of potassium (K), copper (Cu), manganese (Mn), and boron (B) at all the three stages of sampling. Concentrations of the following key nutrient elements significantly varied: phosphorus (P), calcium (Ca), magnesium (Mg), zinc (Zn), and Cu at stage 1; K, Ca, Mg, Zn, iron (Fe), and Mn at stage 2; and nitrogen (N), P, Zn, Fe, and B at stage 3. The performances of rootstocks in terms of relative nutrient accumulation indices (RNAIs) were in the order of Sathgudi (1.00) > Rangpur lime (0.98) > Cleopatra mandarin (0.96) > Trifoliate orange (0.76) > Troyer citrange (0.69). The present study clearly demonstrated that citrus rootstocks employed had differential nutritional behavior and different abilities to utilize plant nutrient elements. Thus, the findings of the present study and the methodology adopted can help the horticultural breeders and nutritionists choose the best rootstock/scion combination having the desirable traits of nutrient utilization ability and also to plan effective fertilizer schedule programs for achieving greater yields. [ABSTRACT FROM PUBLISHER]

There is a rise in number of people diagnosed with Diabetes Mellitus. The incidence is rising in modern Indian society because of Industrial development and drastically changing lifestyles. Diabetic neuropathies are microvascular disorders that are usually associated with the duration of Diabetes. Among the various forms, the most common is Diabetic Peripheral Neuropathy. The disease if neglected leads to chronic ulcer formation leading to amputations frequently. Hence the aim of this study is to document the early cutaneous changes and create an early awareness in the importance of controlling Diabetes. The study consisted of 205 patients with Type 2 DM. Participant's neuropathy status was determined based on Neuropathy Disability Score and Diabetic Neuropathy Symptom Score. Among the Skin changes documented, the common changes seen were: Peripheral hair loss in 185 (90.2%), Xerosis in 168 (82%), Anhydrosis in 162 (79%), Plantar Fissures in 136 (66.3%), Plantar Ulcer in 80 (39%), common nail changes documented were Onychomycosis in 165 (80.5%) and Onychauxis in 53 (25.8%) patients in relation to the occupation and duration of Diabetes mellitus. In conclusion, it is important to control glycemic levels in the all stages of Diabetes and institute foot care measures to prevent the complications of neuropathy. [ABSTRACT FROM AUTHOR]

Abstract: Conventional petroleum jet and diesel fuels, as well as alternative Fischer–Tropsch (FT) fuels and hydrotreated renewable jet (HRJ) fuels, contain high molecular weight lightly branched alkanes (i.e., methylalkanes) and straight chain alkanes (n-alkanes). Improving the combustion of these fuels in practical applications requires a fundamental understanding of large hydrocarbon combustion chemistry. This research project presents a detailed and reduced chemical kinetic mechanism for singly methylated iso-alkanes (i.e., 2-methylalkanes) ranging from C7 to C20. The mechanism also includes an updated version of our previously published C8–C16 n-alkanes model. The complete detailed mechanism contains approximately 7200 species 31400 reactions. The proposed model is validated against new experimental data from a variety of fundamental combustion devices including premixed and non-premixed flames, perfectly stirred reactors and shock tubes. This new model is used to show how the presence of a methyl branch affects important combustion properties such as laminar flame propagation, ignition, and species formation. [Copyright &y& Elsevier]

Abstract: Reduced chemical kinetic mechanisms for methanol combustion were investigated by evaluating ignition delay magnitudes and combustion in a continuously stirred reactor. Unsteady computations were made to study the characteristics of the kinetic mechanisms proposed in the literature and to compare the dependence of various parameters on methanol combustion. All computations were done under isobaric conditions, and, to capture the influence of all the reactions involved in the mechanism, a very small time step was used. Finite-difference methods were used to solve the coupled differential equations. The five-step mechanism developed by C.M. Mueller and N. Peters [in: N. Peters, B. Rogg (Eds.), Reduced Kinetic Mechanisms for Applications in Combustion Systems, Springer-Verlag, New York, 1993, pp. 143–155] for premixed flames and both the five-step mechanism and the four-step mechanisms developed by C.M. Mueller, K. Seshadri, J.Y. Chen [ibid, pp. 284–307] for non-premixed flames were considered. It was found that the Mueller et al. five-step mechanism, with some modifications, best supported the spontaneous ignition and continuous stirred reactor combustion. The results were validated by comparing calculated ignition delays with available experimental data of C.T. Bowman [Combust. Flame 25 (1975) 343–354], and calculated final steady-state concentrations with chemical equilibrium calculations [J.-Y. Chen, Combust. Sci. Technol. 78 (1991) 127]. Initial temperature and concentration and the operating pressure of the system have a major effect on the delay of methanol ignition. The residence time of the continuous stirred reactor affects ignition delay and also changes the transient characteristic of chemical composition of the fuel–vapor mixture. The computations are intended to guide and explain many combustion studies that require a methanol kinetic mechanism. [Copyright &y& Elsevier]

To calculate ignition delay times a skeletal 56-step mechanism for n-heptane is further reduced to a short 30-step mechanism containing two isomers of the n-heptyl-redical and reactions describing both the high temperature and the low temperature chemistry. This mechanism reproduces ignition delay times at various pressures and temperatures reasonably well. Steady state assumptions for many of the intermediate species are introduced to derive separately two global mechanisms for the low temperature regime as well as for the intermediate and high temperature regime. In those formulations the OH radical is depleted by fast reactions with the fuel, as long as fuel is present. Its steady state relation shows that the OH concentration would blow up as soon as the fuel is depleted. Therefore the depletion of the fuel is used as a suitable criterion for ignition.In the intermediate temperature regime the first stage ignition is related to a change from chain-branching to chain-breaking as the temperature crosses a certain threshold. The chain branching reactions result in a build-up of ketohydroperoxides which dissociate to produce OH radicals. This is associated with a slight temperature rise which leads to a crossing of the threshold temperature with the consequence that the production of OH radicals by ketohydroperoxides suddenly ceases. The subsequent second stage is driven by the much slower production of OH radicals owing to the dissociation of hydrogen peroxide. The OH radicals react with the fuel at nearly constant temperature until the latter is fully depleted.In all three regimes analytical solutions for the ignition delay time are presented. The reduced 4-step mechanism of the low temperature regime leads with the assumption of constant temperature to linear differential equations, which are solved. The calculated ignition delay times at fuel depletion compares well with those of the 30-step mechanism. The analysis for the intermediate temperature regime starts from a 4-step subset of a 9-step reduced mechanism. It contains the cross-over dynamics in form of a temperature dependent stoichiometric coefficient which is analysed mathematically. The resulting closed form solutions describe the first stage ignition, the temperature cross-over and the second stage ignition. They also identify the rate determining reactions and quantify the influence of their rates on the first and the second ignition times. The high temperature regime is governed by a three-step mechanism leading to a nonlinear problem which is solved by asymptotic analysis.While the dissociation reaction of the ketohydroperoxide dominates the low temperature regime and the first stage ignition of the intermediate temperature regime, the hydrogen peroxide dissociation takes this role for the second stage of the intermediate and in the high temperature regime. The overall activation energy of the ignition delay time in the low temperature regime is the mean of the activation energies of two reactions only. The overall activation energy of the ignition delay time in the high temperature regime is shown to be related to the activation energies of only three but different rate determining reactions. [Copyright &y& Elsevier]

A set of processes has been explored that enhances the utility of self-assembled-monolayer electron-beam resists for patterning silicon. A self-assembled monolayer resist of octadecylsiloxane was exposed using a scanning electron microscope with a 20 keV beam energy and dose of 320 μC/cm2. After the patterned monolayer was developed using ultraviolet light and ozone, it served as a wet etch mask for the underlying native oxide. Linewidths of ∼30 nm were etched in silicon using the patterned oxide as a reactive ion etch mask. The maximum etch depth achieved in silicon was 90 nm using this process. © 1996 American Institute of Physics. [ABSTRACT FROM AUTHOR]