Vipin Kumar Singh

Analysis of birth intervals in India's Uttar Pradesh and Kerala states

Life tables of birth intervals and median birth intervals in two Indian states, Uttar Pradesh and Kerala, were computed for several subgroups of the study population. Multivariate hazards modelling technique was used to examine the net effect of each of the variables studied. The results show a substantial effect of socioeconomic variables in child-spacing after controlling for the major intermediate variables.

Fungal Endophytes from Seaweeds: An Overview

Seaweeds are macroscopic benthic algal forms, different from microscopic algae and constitute one of the highest productive ecosystems. Marine ecosystem harbors very large diversity of seaweed endophytic fungi. Seaweeds, from different geographical locations, exhibit diversity in associated endophytes as well as secondary metabolites produced by them. Lots of works have been presented on secondary metabolites from endophytic organisms inhabiting in terrestrial and aquatic plants. However, endophytic fungi from marine macro-algae are currently emerging as a novel source of bioactive molecules. These bioactive secondary metabolites from seaweed endophytes have reported antialgal, anticancer, antimicrobial, antiplasmodial, antioxidant, insecticidal, HLE inhibitor, protein phosphatases inhibitor, tyrosine kinase inhibitor and AChE modulation activities which stimulate the scientific community for further search of new compounds. The present chapter highlights the recent developments in diversity of endophytes inhabiting the seaweeds and economically important metabolites synthesized by them as well as scope of future study in this area.

Semilocal Convergence Analysis of S-iteration Process of Newton---Kantorovich Like in Banach Spaces

In the present article, we establish a semilocal convergence theorem for the S-iteration process of Newton–Kantorovich like in Banach space setting for solving nonlinear operator equations and discuss its semilocal convergence analysis. We apply our result to solve the Fredholm-integral equations.

Some Newton-like methods with sharper error estimates for solving operator equations in Banach spaces

It is well known that the rate of convergence of S-iteration process introduced by Agarwal et al. (pp. 61-79) is faster than Picard iteration process for contraction operators. Following the ideas of S-iteration process, we introduce some Newton-like algorithms to solve the non-linear operator equation in Banach space setting. We study the semi-local as well as local convergence analysis of our algorithms. The rate of convergence of our algorithms are faster than the modified Newton method.Mathematics Subject Classification 2010: 49M15; 65K10; 47H10.

Exploring temple floral refuse for biochar production as a closed loop perspective for environmental management

Religious faith and ritual activities lead to significant floral offerings production and its disposal as waste to the nearby open lands and water bodies. These activities result into various social and environmental nuisances because of their high organic content. Alternatively, it can be used as valuable resources for various biochemical and thermo-chemical processes. Floral refuse has been utilized in natural dye extraction, however, the residual solid refuse is of significant environmental concern due to its nutrient rich nature. This study explores the potential utilization of solid residue of temple floral refuse after natural dye extraction by thermo-chemical decomposition of it. The slow pyrolysis of solid residue was performed at 350 °C and 500 °C, and the biochar yield of 42 and 36% was obtained, respectively. TGA-DTG analysis was performed to observe the thermo-chemical behaviour of floral refuse. The biochar products were further characterized by FTIR, SEM, EDX, BET, XRD, and RAMAN spectroscopy to observe the impact of pyrolysis temperature (PT) on the resulting material, i.e. biochar and its possible application measures. EDX results revealed the presence of various macro-nutrients such as C, N, P, K Ca and Mg in different proportions which showed its soil amelioration potential. Moreover, based on the SEM and BET results, biochar prepared at 500 °C was further explored for adsorption of methylene blue dye at various dose and pH conditions. Based on Langmuir (R2 = 0.98) and Freundlich (R2 = 0.97) isotherms, it is found as a potential adsorbent material for removal of methylene blue dye. The results revealed that biochar conversion of colour extracted floral refuse can be a vital option for quick and efficient management of it in a closed loop approach.

Concentrations, sources and health risk of nitrated- and oxygenated-polycyclic aromatic hydrocarbon in urban indoor air and dust from four cities of Nepal

Although the fate and behavior of parent polycyclic aromatic hydrocarbon (PAHs) have been documented worldwide, the information about PAH-derivatives (NPAHs and OPAHs) is limited, especially in developing countries, including Nepal. Moreover, the greater parts of the investigations concentrating on NPAHs/OPAHs are on the air (borne) particulate phase only; and are primarily based on a limited number of compounds analyzed. Little is known about the environmental concentration, fate, and behavior of NPAHs and OPAHs in air gas phase and dust. In this study, the concentration, fate, spatial distributions of 26 NPAHs and 3 OPAHs in the air (n = 34) and dust (n = 24) were investigated in suspected source area/more densely populated areas of Nepal. Four critical source areas in Nepal were considered as it was conjectured that the urban areas are more prone to NPAH/OPAH contamination due to the high density of automobiles and industrial activities. Overall, the measured ∑19NPAHs in air and dust were 5 and 2 times lower than their parent-PAHs, respectively. Highest levels of NPAHs/OPAHs were measured in Birgunj, followed by Kathmandu, Biratnagar, and Pokhara, respectively, while Biratnagar showed the highest level of ∑OPAHs. 3-Nitrodibenzofuran (3-NDBF) was the most abundant NPAHs measured both in air and dust, whereas 9-Fluorenone (9-FLUONE) prevailing OPAHs. The molecular diagnostic ratio (MDR) of 2-Nitrofluoranthene/1-Nitropyrene indicated the contribution from secondary emission via photochemical reaction as the primary source of NPAHs, while solid fuel combustion and crop residue burning were identified as the essential sources of OPAHs. The human exposure to NPAH/OPAH through the different route of intake suggested dermal contact via dust as the primary pathway of NPAH/OPAH exposure for both adult and children. However, other routes of exposure, for instance, dietary intake or dermal absorption via soil may still be prominent in case of Nepal.

Plant Growth-Promoting Rhizobacteria (PGPR): Perspective in Agriculture Under Biotic and Abiotic Stress

Abstract Knowledge of rhizosphere ecology and its impact on plant physiology has dramatically changed traditional agricultural practices, especially in the context of plant defense mechanisms against biotic and abiotic stresses. It is a universally accepted fact that certain rhizosphere-associated strains, referred to as plant growth-promoting rhizobacteria (PGPR), stimulate plant growth and fitness. Since PGPR in symbiotic interactions are an integral part of the living ecosystem, they are believed to be the natural partners that modulate local and systemic mechanisms in plants to offer defense under adverse external conditions. PGPR producing secondary compounds that may act as signals—that is, allelochemicals—induce plant immunity against pathogen attack. Moreover, multifaceted role of PGPR is now being widely implemented for mitigating abiotic stress caused and induced by climate alternations and for restoring natural soil against variety of toxic metals. Future research demands interdisciplinary research that may pave the significant role of PGPR in modulating/introducing new crop traits under adverse conditions.

Iron oxidizing bacteria: insights on diversity, mechanism of iron oxidation and role in management of metal pollution

In natural ecosystems, diverse iron oxidizing bacteria are of common occurrence. Basically, two different mechanisms have been proposed for catalysis of iron oxidation by bacterial metabolic systems which differ mainly at cytochrome and rusticyanin level. Biological iron oxidizers not only affect the cycling of iron but also efficiently minimize the concentrations of hazardous metals such as lead, nickel, copper, chromium, cadmium and cobalt. The ferric iron generated after biological oxidation forms complexes with metals/metalloids present in their vicinity. Ferric ions produced by biological actions also act as catalyst for oxidation of toxic metalloid such as arsenite (As III) converting it into less toxic form. Most importantly, bacterial iron oxidizers have commercially been employed in industrial bioleaching for the recovery of important elements and remediation of acid mine drainage water. Currently, heavy metal contamination has emerged as one of the prime concerns for the world and is posing serious threats to both environment and human health. Although varieties of physical and chemical techniques are currently being used to manage the metal contamination, treatment using biological iron oxidation approaches are convincing because of their ecofriendly nature and low sludge generation. In the present review we have tried to focus on the diversity of bacterial iron oxidizers, mechanisms of iron oxidation by bacterial species, and role of bacterial iron oxidizers in bioremediation of metal pollutants along with future research possibilities in this area.

Semiochemical footprints of the predaceous coccinellid beetle, Menochilus sexmaculatus, deter Zygogramma bicolorata (Coleoptera: Chrysomelidae) from feeding on Parthenium

ABSTRACT Present study assessed if semiochemical cues left by an aphidophagous beetle, M. sexmaculatus influenced foraging behaviour of a phytophagous beetle, Z. bicolorata on noxious weed, P. hysterophorus. The lower predation attributes of Z. bicolorata in presence of M. sexmaculatus semiochemical footprints confirms they interfere with weed biological control.

Role of Pseudomonas sp. in Sustainable Agriculture and Disease Management

Recently the growing population and climate change are the most severe challenge for both farmers and researchers from the last two decades. It is estimated that by 2050 the global population reaches to ~9 billion which demands ~60% extra food from the present, which creates extra pressure on the farmers to achieve the need of food. The farmers currently utilized huge amount of chemical fertilizers and pesticides to enhance the food production and disease management. These chemical fertilizers not only affect the texture and productivity of soil but also the health of plants, humans, and environment. From the last two decades, plant growth-promoting bacteria (PGPB) is one of the best choices as plant and soil inoculants to enhance the plant growth and disease management, due to their less impact on environment and eco-friendly nature. In this chapter, we focused on one of the most broadly used bacterial genus, Pseudomonas, which is present in the rhizosphere as well as within the tissue of the plants and used in sustainable agriculture for the enhancement of growth promotion and disease management.