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Supermarket procurement and farmgate prices in India
Supermarkets have gained in importance in the food systems of many developing countries, with profound implications for smallholder farmers. Several studies analyzed effects of selling to supermarkets on smallholder productivity and income. However, no previous work systematically analyzed effects of supermarkets on farmgate prices, even though prices are important determinants of farmers profits and livelihoods. Here, we use data from smallholder vegetable growers in India to compare output prices received in supermarket and traditional market channels. We also quantify farmers transport and transaction costs in both channels. Even after controlling for quality differences, prices are significantly higher in supermarket channels. Positive price effects are confirmed through hedonic price models and propensity score matching. Average effects of supermarkets on farmgate prices are in a magnitude of 20% or more. Higher farmgate prices are due to fewer intermediaries and lower transaction costs in supermarket channels. In the absence of binding contracts, supermarkets also need to pay higher prices to ensure regular supply of high-quality vegetables. These results suggest that the rise of supermarkets can contribute to increased market efficiency with positive effects on farmgate prices and revenues. 2020 The Authors -
Superior charge discharge ability of reduced graphene oxide/Li-ion embedded polymer composite films
Electroactive polymeric composites are recent generation material for energy application in lithium batteries, solar cells and supercapacitors. In present study, reduced graphene oxide is prepared from graphite powder using liquid exfoliation. The synthesized reduced graphene oxide is embedded with polystyrene sulfonic acid/lithium phosphate polymer electrolyte to obtain polymer composite films. The dielectric studies of composite reveals huge change in relaxation time with addition of rGO in polymeric lithium ion composites. This attributes to decrease in ion-dipolar interaction strength and enhanced polymer segmental motion in presence of carbon. It also implies the activation of electrochemical properties of polystyrene sulfonic acid/lithium phosphate/reduced graphene oxide (PLrGO) composites which can be effectively utilize for charge storage applications. The PLrGO composite exhibits an improved electrochemical performance with different scan rate on potential window ranged between ? 0.5 and 1.2V. The specific capacitance value of ~ 17F/g with high rate chargedischarge capability over 8000 cycles was observed. Higher electrochemical stability and steady charge/discharge behavior makes PLrGO composites a promising candidate for charge storage applications. 2018, Springer Science+Business Media, LLC, part of Springer Nature. -
Supercapacitor studies of activated carbon functionalized with poly(ethylene dioxythiophene): Effects of surfactants, electrolyte concentration on electrochemical properties
Electropolymerization of poly(ethylene dioxythiophene) (PEDOT) on activated carbon (AC) was performed using different surfactants such as anionic surfactant (sodium dodecyl sulfate), protonic surfactant (camphor sulphonic acid) and non-ionic surfactant (Triton) in 0.1 M H2SO4. The effects of concentration of different surfactants for electrodeposition of PEDOT on AC were analyzed using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and SEM techniques. Supercapacitors (SC) were fabricated using AC/PEDOT composite electrodes and 0.1 M H2SO4 as an electrolyte. The specific capacitance (Cs) values were calculated using CV at different concentrations of surfactants, electrolytes and variation of potential. The electrolyte containing 0.1 M H2SO4 and 0.02 M camphor sulphonic acid showed to have the highest specific capacitance value of 240 Fg?1 than other surfactant based SCs. Galvanostatic charge/discharge at varying current density were performed on SCs containing different surfactant based electrodes to study their cyclic stability. 2020 -
Super strongly perfect graphs
Some of the published results on super strongly perfect graphs are found to be erroneous. We provide some examples and counter examples on the concepts associated with super strongly perfects. 2022 World Scientific Publishing Company. -
Sunova spirulina Powder as an Effective Environmentally Friendly Corrosion Inhibitor for Mild Steel in Acid Medium
Abstract: Spirulina, blue green algae is a rich source of proteins and vitamins with excellent antioxidant properties. Sunova spirulina powder an effective, green corrosion inhibitor was used to evaluate its inhibition efficiency towards mild steel in 1M HCl medium. Weight loss studies of mild steel showed an inhibition efficiency of 96% for 600ppm concentration of inhibitor solution and 12h of immersion period at 303K. The percentage of inhibition efficiency increased with a step up of 10K raise in temperature from 303 to 333K and thereafter decreased. The results obtained were further validated by inductively coupled plasma optical emission spectrometric (ICP-OES) measurements and electrochemical techniques that included Tafel polarisation, linear polarisation and AC impedance studies. Potentiodynamic polarisation study marked the inhibitor to be a mixed type inhibiting both cathodic and anodic reactions. The adsorption studies proved that the adsorption process was spontaneous and followed Langmuir adsorption isotherm. The thermodynamic activation and adsorption parameters calculated showed that the mechanism of inhibition involved a physisorption process initially and then it slightly shifted towards chemisorption process at higher temperature. The protective layer formed on the metal surface was studied using FTIR and SEM. The complex formation between the Fe2+ and the active constituents of the spirulina extract was verified using UV visible spectra and fluorescence spectra. The effect of inhibitor concentration and temperature on corrosion rate was tested statistically using two-way analysis of variance (ANOVA) technique. Graphic Abstract: [Figure not available: see fulltext.]. 2020, Springer Nature Switzerland AG. -
Sumset valuations of graphs and their applications
Graph labelling is an assignment of labels to the vertices and/or edges of a graph with respect to certain restrictions and in accordance with certain predefined rules. The sumset of two non-empty sets A and B, denoted by A+B, is defined by A+B=\(a=b: a\inA, b\inB\). Let X be a non-empty subset of the set \Z and \sP(X) be its power set. An \textit of a given graph G is an injective set-valued function f: V(G)\to\sP_0(X), which induces a function f+: E(G)\to\sP_0(X) defined by f+(uv)=f(u)+f(v), where f(u)+f(v) is the sumset of the set-labels of the vertices u and v. This chapter discusses different types of sumset labeling of graphs and their structural characterizations. The properties and characterizations of certain hypergraphs and signed graphs, which are induced by the sumset-labeling of given graphs, are also done in this chapter. 2020, IGI Global. -
Sum Signed Graphs, Parity Signed Graphs and Cordial Graphs
Signed graphs are graphs with every edge is signed either positive or negative. Given an n vertex graph, the vertices are bijectively labelled from 1 to n. A signed graph is a sum signed graph if and only if every edge is signed negative whenever the sum of the vertex labels exceeds n and every edge is signed positive whenever the sum of the vertex labels does not exceed n. For a parity signed graph, an edge receives a negative sign, if the end vertices are of opposite parity and a positive sign otherwise. Cordial signed graphs are the ones with the difference between the total number of negative edges and the positive ones is at most 1. We discuss the connection between sum signed labeling with parity signed labeling and cordial labeling. The absolute cordial condition for graphs satisfying sum signed labeling will be analyzed 2023, IAENG International Journal of Applied Mathematics.All Rights Reserved. -
Sum signed graphs - I
Let G=(V,E) be a simple graph, f: V(G) ? {1, 2, ..., |V(G)|} be a bijective function and ?: E(G) ? {+,-} be a mapping such that ? (uv)=+, whenever f(u)+f(v) ? n and ? (uv)=-, whenever f(u)+f(v)>n. Then, S=(G,f,?) is said to be a sum signed graph. In this paper, we initiate the study of sum signed graphs. Also, we find rna number for some classes of graphs and present some of the characteristics of sum signed graphs. 2020 Author(s). -
SUM SIGNED GRAPHS II
In this paper, the study of sum signed graphs is continued. The balancing and switching nature of the graphs are analyzed. The concept of rna number is revisited and an important relation between the number and its complement is established. 2023, Krasovskii Institute of Mathematics and Mechanics. All rights reserved. -
Sum Signed Graph
A sum signed graph S = (G, f, and#963;) is a signed graph of the underlying graph G where f : V (G) and#8722;and#8594; {1, 2, . . . , | V (G) |} is a bijective function and and#963; : E(G) and#8722;and#8594; {+, and#8722;} is newlinea mapping such that and#963;(uv) = +, whenever f(u) + f(v) and#8804; n and and#963;(uv) = and#8722;, whenever f(u) + f(v) gt n. The minimum number of negative and positive edges among all the sum signed labelings of G is known as rna and rna complement number respectively. The maximum number of positive edges among all the sum signed labelings of G is known as adhika number. The set X and#8838; V (G) is said to be a s - dominating of a signed graph whenever X is a dominating set and there exists exactly s number of negative edges between X and its complement. The minimum cardinality of such a dominating set over all signed graphs of the graph G is called an s - domination number. newlineIn the present study, we initiate the study of a new labeling in signed graphs namely, newlinesum signed labeling. The characteristics of sum signed graphs and the bound of rna number of in terms of the number of vertices in the underlying graph are explored by examining the rna number of different graphs. The properties of signed graphs such as negating and balancing is analyzed. The relation between rna number and rna complement number is established. The connection of sum signed labeling with parity signed labeling and cordial labeling is discussed. The absolute cordial condition for graphs satisfying sum signed labeling is examined. The concept of s - domination was also introduced during this period of study. The s domination in both the positive and negative homogeneous signed graph is investigated for each value of s. The properties of s domination in sum signed graphs are also analyzed. The s - domination number for specifc values of s is investigated for various graphs. The maximum value of s for a graph for which the s - domination will exist is discussed. -
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Sulphuric acid supported silica gel (H2SO4-SiO2) as an efficient catalyst for one-pot multicomponent synthesis of pyrano[2,3-c]pyrazol-amines under ultrasonication
In this study, the catalytic potential of a novel heterogeneous catalyst-sulphuric acid supported on silica gel (H2SO4-SiO2) has been assessed for the one-pot cyclo condensation reaction of aromatic aldehydes, 4-nitrophenylacetonitrile, ethyl acetoacetate and hydrazine/phenyl hydrazine to furnish poly functionalized pyrano[2,3-c]pyrazol-amine scaffolds under ultrasonication. Notably, within the framework of green chemistry, this divergent and step-economic approach has many benefits such as (i) use of water as solvent in the reaction, (ii) creation of up to five bonds in one sequence, (iii) avail of US irradiation as an efficient source of energy, (iv) application of nontoxic and reusable catalyst. Besides these, simple workup procedure, low catalyst loadings, shorter reaction time, high functional group compatibility, readily accessible starting materials and excellent yields without column chromatography render this protocol novel and greener towards the synthesis of poly functionalized pyrano[2,3-c]pyrazol-amines. 2020 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the Second International Symposium ''Functional Nanomaterials in Industrial Applications: Academy - Industry Meet''. -
Sulfamic acid catalyzed grinding: A facile one-pot approach for the synthesis of polysubstituted pyrazoles under green conditions
A competent, rapid and simple grinding procedure for the synthesis of pharmacologically relevant polysubstituted pyrazoles catalyzed by sulfamic acid is reported via multicomponent reaction of substituted arylaldehydes, 4-nitrophenylacetonitrile, hydrazine hydrate, ethyl acetoacetate under solvent-free reaction conditions. In our reported protocol, four different reactants featuring diverse functional groups are assembled in one pot, enabling the synthesis of more diverse molecular structures in a facile manner. 2022 -
Suitability of natural rubber latex and waste foundry sand in cement concrete
Suitability of Natural Rubber Latex (NRL) as an additive and Waste Foundry Sand (WFS) as partial replacement to river sand, in cement concrete was investigated. Experimental study was performed with concrete mixtures containing 1% latex to water ratio, along with 5% and 10% replacement of river sand by WFS. Properties of concrete were studied in both fresh and hardened state. The results of laboratory tests indicate that WFS and NRL reduces the workability of concrete. Slight reduction in splitting tensile strength was observed for mixtures containing NRL and WFS, in comparison to conventional mix. No specific trend was observed for flexural strength at 7 days, but at 28 days the difference was within 3%, when compared to conventional mix. Strength development for mixtures containing NRL and WFS was slightly lower than conventional mix. The limited results of this study show that concrete containing NRL and WFS do have potential for use as non-structural concrete. -
Suicide and Youth: Positive Psychology Perspective
Suicidality and self-harm among adolescents and young adults need immediate attention and support. This is often seen as a cry for help where a feeling of entrapment experienced by individuals pushes them to see self-harm as a coping mechanism. Lack of social support and co-morbid emotional disorders influences suicidal ideation into planning and action. A general feeling of helplessness that gets triggered often leads to anguish. These emotions get internalized and directed inwards leading to self-directed anger which facilitates a suicidal act. Early detection and identification can prevent the loss of lives and help individuals to learn effective ways of coping. Gatekeeper Training for caregivers, teachers, and their peers will help in detecting the early signs of suicide risk. Intervention based on positive psychology will help not only in crisis management but also as preventive and maintenance therapy in holistic mental health. The concepts of hope, forgiveness, self-compassion, gratitude, and resilience can be incorporated into the intervention programs to build a better therapeutic system for youths dealing with suicidality. Practicing effective coping mechanisms every day and making it a ritual of ones daily life is the need of the hour. Integrating adaptive ways of emotional expression and learning matured means to deal with painful emotions and trauma is what needs to be incorporated into the intervention plan. The chapter focuses on these aspects and aims to make a connection between assessing and easy identification of youths in distress related to suicidality and providing a holistic intervention to help them cope with the situation. The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023. -
Suicide among children during Covid-19 pandemic: An alarming social issue
[No abstract available] -
Suicidal behavior prediction using data mining techniques
Background: Suicide is one of the most serious public health problem that has affected many people. After being recognized as a public health priority by the WHO (World Health Organization) various studies have been going out for its prevention. It is one of a serious health problem and it is preventable and can be controlled by proper interventions and study in the field. The objective of the study is to create a prediction model for individuals who are at higher risk of suicide by studying the different predictors of suicide such as depression, anxiety, hopelessness, stress etc. by using data mining techniques for the prediction. Study Design: Systematic review and predictive analysis for suicidal behavior. Methods: The research applies data mining process to analyze the data and on the basis of analysis create the model to predict suicidal behaviors present in the individual. Prediction is done on the basis of analysis of risk factors which are Depression, anxiety, hopelessness, stress, or substance misuse which is calculated by using various psychological measures such as Beck hopelessness scale,suicidal ideation subscale,hospital anxiety and depression scale.Various data mining algorithms for classification are compared for the purpose of prediction. Results: Six different data mining classification algorithms which are namely Classification Via Regression, Logistic Regression. Random Forest, Decision Table, SMO are compared and Classification Via Regression was found to the highest accuracy in prediction. Conclusions: Data required for the development of such a model requires continuous monitoring and needs to be updated on a periodic basis to increase the accuracy of prediction. IAEME Publication. -
Sugarcane Leaf Disease Classification Using Convolutional Neural Network
Indian sugarcane is of good quality, and the country exports significant quantities of sugar and sugarcane-based products to various countries worldwide. However, the quality of the sugarcane can vary depending on the specific variety and growing conditions, and exporters need to ensure that the product meets the quality standards of the importing country. To maintain the quality of sugarcane during transportation, it is crucial to ensure that it is harvested at the right time and handled carefully during loading and unloading. However, the farmers cultivating the sugarcane face a significant issue dealing with bacterial infection in the plants. In order to stop the disease from spreading further, we use Convolutional Neural Networks in our article to extract information from sugarcane leaves and construct an algorithm that accurately classifies bacterial leaves. Using an image dataset that includes pictures of both healthy and ill plants, identifying the image's key characteristics, and using the image to help the classifier provide a reliable result are all included in the total process. Our study will save farmers time and effort by identifying the decaying plants by looking for bacterial patches on the leaves. 2024 IEEE. -
Suction-injection effects on the onset of Rayleigh-Bard-Marangoni convection in a fluid with suspended particles
The effect of Suction-Injection-Combination (SIC) on the linear stability of Rayleigh-Bard Marangoni convection in a horizontal layer of an Boussinesq fluid with suspended particles confined between an upper free adiabatic boundary and a lower rigid isothermal/adiabatic boundary is considered. The Rayleigh-Ritz technique is used to obtain the eigenvalues. The influence of various parameters on the onset of convection has been analysed. It is found that the effect of Prandtl number on the stability of the system is dependent on the SIC being pro-gravity or anti-gravity. A similar Pre-sensitivity is found in respect of the critical wave number. It is observed that the fluid layer with suspended particles heated from below is more stable compared to the classical fluid layer without suspended particles. The problem has possible applications in microgravity situations. -
Succession planning in India: The path less traversed /
The Management Accountant, Vol.54, Issue 2, pp.30-33, ISSN No: 2581-5504.