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In this paper, we construct a modification of Sz?sz-Mirakyan operators with a new technique that preserved the exponential functions i.e. exp(?t) and exp(2?t), for a fixed real parameter ? > 0. We study the asymptotic behaviour and weighted approximation of these operators. Comparisons about one approximate better between the recent operators and the classical Sz?sz-Mirakyan operators have also been presented. In the end, we compare the convergence of these operators and modified Baskakov operators to certain functions by illustrative graphics using the Mathematica algorithms.

This article investigates the approximation properties of a general family of positive linear operators defined on the unbounded interval [0,?). We prove uniform convergence theorem and Voronovskayatype theorem for functions with polynomial growth. More precisely, we study weighted approximation i.e basic convergence theorems, quantitative Voronovskaya-asymptotic theorems and Gr?ss Voronovskayatype theorems in weighted spaces. Finally, we obtain the rate of convergence of these operators via a suitable weighted modulus of continuity.

Graphical abstract The pandemic has affected almost 74 million people worldwide as of 17 December 2020. This is the first study that attempts to examine the nexus between the confirmed COVID-19 cases, deaths, meteorological factors, and the air pollutant namely PM2.5 in six South Asian countries, from 1 March 2020 to 30 June 2020, using the advanced econometric techniques that are robust to heterogeneity across nations. Our findings confirm (1) a strong cross-sectional dependence and significant correlation between COVID-19 cases, deaths, meteorological factors, and air pollutant; (2) long-term relationship between all the meteorological variables, air pollutant, and COVID-19 death cases; (3) temperature, air pressure, and humidity exhibit a significant impact on the COVID-19 confirmed cases, while COVID-19 confirmed cases and air pollutant PM2.5 have a statistically significant impact on the COVID-19 death cases. In this way, the conclusion that high temperature and high humidity increase the transmission of the COVID-19 infections can also be applied to the regions with greater transmission rates, where the minimum temperature is mostly over 21 °C and humidity ranges around 80% for months. From the findings, it is evident that majority of the meteorological factors and air pollutant PM2.5 exhibit significant negative and positive effects on the number of COVID-19 confirmed cases and death cases in the six countries under study. Air pollutant PM 2.5 provides more particle surface for the virus to stick and get transported longer distances. Hence, higher particulate pollution levels in the air increase COVID-19 transmission in these six South Asian countries. This information is vital for the government and public health authorities in formulating relevant policies. The study contributes both practically and theoretically to the concerned field of pandemic management. Supplementary Information The online version contains supplementary material available at 10.1007/s11356-021-12613-6.

In this work, we present a Durrmeyer-type operator having the basis functions in summation and integration due to Aral (Math Commun 24:119–131, 2019) and Pǎltǎnea (Carpath J Math 24(3):378–385, 2008) that preserve the constant functions. We compute the rate of convergence of these operators in a weighted space and also computed a quantitative Voronovskaja-type asymptotic formula as well as a Gruss-Voronovskaya-type approximation.

In the present article, we deal with the overconvergence of the Szász-Durrmeyer-Chlodowsky operators. Here we study the approximation properties e.g. upper estimates, Voronovskaja type result for these operators attached to analytic functions in compact disks. Also, we discuss the exact order in simultaneous approximation by these operators and its derivatives and the asymptotic result with quantitative upper estimate. In such a way, we put in evidence the overconvergence phenomenon for the Szász-Durrmeyer-Chlodowsky operators, namely the extensions of approximation properties with exact quantitative estimates and orders of these convergencies to sets in the complex plane that contain the interval [0, ∞).

In this article, we present the Durrmeyer variant of generalized Bernstein operators that preserve the constant functions involving a non-negative parameter $$\rho $$ . We derive the approximation behaviour of these operators including a global approximation theorem via Ditzian–Totik modulus of continuity and the order of convergence for the Lipschitz type space. Furthermore, we study a Voronovskaja type asymptotic formula, local approximation theorem by means of second order modulus of smoothness and the rate of approximation for absolutely continuous functions having a derivative equivalent to a function of bounded variation. Lastly, we illustrate the convergence of these operators for certain functions using Maple software.

In this note, we present a Durrmeyer-type modification of generalized Lupas operators depending on certain parameter $$\rho >0$$ . We establish quantitative asymptotic result, some direct results, weighted approximation and the order of convergence for the functions having a derivative equivalent with a function of bounded variation for these operators.

Chickpea (Cicer arietinum L.) is mainly grown in rainfed area and terminal drought stress is one of the major constrain to chickpea production in India. The present study was undertaken to identify the traits of significance that contribute towards terminal drought tolerance in chickpea. The two chickpea genotypes HC-1 (drought sensitive) and RSG 931 (drought tolerant) and F3 progeny lines of cross HC-1 × RSG 931 were grown in drought microplots and data was recorded for root and physiological traits under terminal drought stress. The results showed wide variation for root and physiological traits in HC-1, RSG 931 and F3 progeny lines of chickpea. Significant positive correlation was recorded between seed yield and water potential; seed yield and RWC; seed yield and quantum yield of photosystem II,,whereas root traits were not positively correlated with seed yield. The results of present study showed that physiological parameters could be reliable tools for screening of terminal drought tolerance in chickpea.

In the present article, we introduce a general sequence of summation-integral type operators. We establish some direct results which include Voronovskaja type asymptotic formula, point-wise convergence for derivatives, error estimations in terms of modulus of continuity and weighted approximation for these operators. Furthermore, the convergence of these operators and their first order derivatives to certain functions and their corresponding derivatives respectively is illustrated by graphics using Matlab algorithms for some particular values of the parameters c and ?.

The purpose of this note is to obtain some direct results for the modified Bernstein–Kantorovich operators for functions of one variable proposed by Ozarslan and Duman (Numer Funct Anal Optim 37:92–105, 2016). We also introduce the bivariate extension of these operators and compute the Voronovskaja type asymptotic formula, the degree of approximation for the Lipschitz class of elements and order of approximation by means of the Peetre’s K-functional. We illustrate the convergence of the operators to a certain function with the help of Mathematica software.

In this paper, we introduce the Bezier variant of the Jakimovski–Leviatan–Paltanea operators based on Appell polynomials. We establish some local results, a direct approximation theorem by means of the Ditzian–Totik modulus of smoothness and also study the rate of convergence for the functions having a derivative of bounded variation for these operators.

In this paper, we construct generalized Baskakov Kantorovich operators. We establish some direct results and then study weighted approximation, simultaneous approximation and statistical convergence properties for these operators. Finally, we obtain the rate of convergence for functions having a derivative coinciding almost everywhere with a function of bounded variation for these operators.

The delivery and binding of the therapeutic molecules like drugs, siRNAs and toxins to their specific target is a challenging task. Poor efficacy and off target binding are major problems associated with current approaches for targeted delivery of therapeutic molecules. Therefore, to avoid off target binding, target specific delivery systems are urgently required. Over the years, aptamers have become attractive molecules for targeted delivery of drugs. Aptamers are defined as small, single-stranded DNA/RNA or peptides which can bind to the specific targets with better affinity. The therapeutic molecules can either conjugate directly to the aptamers or along with some carrier molecules like liposomes, antibodies and nanoparticles to achieve specific targeted delivery. The present book chapter will focus on aptamer mediated target specific delivery of drugs, toxins and siRNAs- both direct conjugation with aptamer and in association with carriers.

Environmental pollutants monitoring is utmost importance for safety of living being of our ecosystem. Though the traditional detection techniques are capable of accurate analysis of environmental pollutants, there is need to develop fast, real-time and cost-efficient techniques for detecting and monitoring the environmental pollutants. Aptamer-based biosensors have shown promising performance in the detection of environmental contamination due to their high sensitivity, specificity and reusability. The aptasensor acts as an analytical device, which uses an aptamer as a ligand molecule. Aptamer is recently emerging as potential sensing elements that can replace other ligands due to its high temperature stability, low-immunogenicity, low-toxicity, high affinity and high specificity. This chapter explains the advances in development of aptasensor and its applications in the detection of various environmental contaminants.

WOS: 000500241100006 In this note, we present Kantorovich modification of the operators introduced by V. Mihesan [Creative Math. Inf. 17 (2008), 466 - 472]. First, we derive some indispensable auxiliary results in the second section. We present a quantitative Voronovskaja type theorem, local approximation theorem by means of second order modulus of continuity and weighted approximation for these operators. Furthermore, we show the rate of convergence of these operators to certain functions with the help of the illustrations using Maple algorithms.

In this paper, we introduce the Bezier variant of the generalized Baskakov Kantorovich operators. We establish a direct approximation theorem with the aid of the Ditzian–Totik modulus of smoothness and also study the rate of convergence for the functions having a derivative of bounded variation for these operators.

We introduce a one parameter family of hybrid operators and study quantitative convergence theorems for these operators e.g. local and weighted approximation results and simultaneous approximation of derivatives. Further, we discuss the statistical convergence of these operators. Lastly, we show the rate of convergence of these operators to a certain function by illustrative graphics in Matlab.

The aim of this paper is to present a Stancu type Kantorovich modification of q-Bernstein-Schurer operators introduced by Muraru (Mathematica LVI 2:1–11, 2011) and modified by Ren and Zeng (Bull Korean Math Soc 50(4):1145–1156, 2013). Here, we obtain a convergence theorem by using the well known Bohman-Korovkin criterion and find the estimate of the rate of convergence by means of modulus of continuity and Lipschitz function for these operators. Also, we establish a Korovkin type A-statistical approximation theorem.

In the present paper, we introduce the q-analogue of the general Gamma type operators. We establish the moments of the operators by using the q-derivatives and then prove the basic convergence theorem. Next, the Voronovskaja type theorem and some direct results for the above operators are discussed. Also, the rate of convergence and weighted approximation by these operators in terms of modulus of continuity are studied. Then, we obtain point-wise estimate using the Lipschitz type maximal function. Further, we study the A -statistical convergence of these operators. Lastly, we propose a king type modification of these operators to obtain better estimates.

The 5-enolpyruvylshikimate-3-phosphate (EPSP) synthase is one of the essential enzymes of shikimate pathway and is verified as a specific target of broad-spectrum herbicide glyphosate. It is important to get insights into three-dimensional (3D) structure of this enzyme for engineering new herbicides as well as herbicide resistant crops. The information about 3D structure of EPSP synthase enzyme is not yet available in protein database for any of the plant species. Therefore, we revealed the homology model of Phaseolus vulgaris EPSP synthase protein using the structure of EPSP synthase from E. coli as template. The resulting model structure was refined by RAMPAGE server, ERRAT and Verify3D. Ramachandran plot analysis showed that conformations for 95.6% of amino acid residues are within the most favoured region. The phylogenetic tree (constructed using MAFFT) separated EPSP synthases of bacteria, monocot and dicot plants into distinct clusters. Our study generated reliable 3D model structure of EPSP synthase in P. vulgaris, which can be used for future studies.

In the present paper, we obtain some approximation properties for the bivariate Bernstein-Durrmeyer operators on a triangle. We characterize the rate of convergence in terms of K-functional and the usual and second order modulus of continuity. We estimate the order of approximation by Voronovskaja type result and illustrate the convergence of these operators to a certain function through graphics using Mathematica algorithm. We also discuss the comparison of the convergence of the bivariate Bernstein-Durrmeyer operators and the bivariate Bernstein-Kantorovich operators to the function through illustrations using Mathematica. Lastly, we study the simultaneous approximation for first order partial derivatives and the shape preserving properties of these operators.

Soon after the discovery of lasers in the 1960s it was realized that laser therapy had the potential to improve wound healing and reduce pain, inflammation and swelling. Today, dentists have a variety of wavelengths to choose from the growing industry of lasers. Also, the field has broadened to include light-emitting diodes and other light sources, and the range of wavelengths used now includes many in the red and near infrared. Each wavelength has a unique interaction with the target tissues of the oral cavity. Laser dentistry, formerly embraced only by the speciality of oral and maxillofacial surgery, now, is positively affecting every field of dentistry. From pediatric and operative dentistry to periodontics, prosthetics to cosmetics and implantology, lasers have made a tremendous impact on the delivery of dental care in the 21st century and will continue to do so as the technology continues to improve and evolve. As low level lasers are more biocompatible than hard lasers, they are evolving rapidly. This article discusses low level laser therapy technology, its dosage, their application in every field of dentistry and risks associated with them, so that they can be used in delivery of superior dental care.

The purpose of this paper is to obtain some direct results for the Durrmeyer variant of q-Bernstein-Schurer operators for functions of one variable introduced by Acu et al. [1]. We also propose to study the bivariate extension of these operators and discuss the rate of convergence by using the modulus of continuity, the degree of approximation for the Lipschitz class of functions and the Voronovskaja type asymptotic theorem. Furthermore, we show the convergence of the operators by illustrative graphics in Maple to certain functions in both one and two dimensional cases. (C) 2015 Elsevier Inc. All rights reserved.

Objective: Multiple drug resistance (MDR) in bacteria, particularly Gram-negative bacilli, has significantly hindered the treatment of infections caused by these bacteria. This results in the need for identifying new drugs and drug targets for these bacteria. The objective of this study was to identify novel drug targets in Acinetobacter baumannii which has emerged as a medically important pathogen due to an increasing number of infections caused by it and its MDR property. Methods: In our study, we implemented in silico subtractive genomics approach to identify novel drug targets in A. baumannii American type culture collection 17978. Various databases and online software were used to build a systematic workflow involving comparative genomics, metabolic pathways analysis, and drug target prioritization to identify pathogen-specific novel drug targets. Results: First, 458 essential proteins were retrieved from a database of essential genes, and by performing BLASTp against Homo sapiens, 246 human non-homologous essential proteins were selected of 458 proteins. Metabolic pathway analysis performed by Kyoto Encyclopedia of Genes and Genomes–Kyoto Automatic Annotation Server revealed that these 246 essential non-homologous proteins were involved in 66 metabolic pathways. Among these metabolic pathways, 12 pathways were found to be unique to Acinetobacter that involved 37 non-homologous essential proteins. Of these essential non-homologous proteins, 19 proteins were found in common as well as unique metabolic pathways and only 18 proteins were unique to Acinetobacter . Finally, these target proteins were filtered to 9 potential targets, based on subcellular localization and assessment of druggability using Drug bank, ChEMBL, and literature. Conclusion: Our study identified nine potential drug targets which are novel targets in A. baumannii and can be used for designing drugs against these proteins. These drugs will be pathogen specific with no side effects on human host, as the potential drug targets are human non-homologous.

Drought stress is one of the major constraints that greatly limit the productivity of wheat worldwide. Deciphering the molecular basis of drought tolerance can help in combating drought stress. Therefore, the present study was undertaken to determine genetic diversity among six drought tolerant and six drought sensitive varieties of wheat. Out of 15 ISSR primers used, 14 primers gave reproducible banding pattern. These 14 primers generated 191 amplified products out of which 93 were polymorphic. Overall size of PCR amplified products ranged between 400 bp and 4000 bp. Based on similarity matrix data, the value of similarity coefficient ranged from 0.70 to 0.94. Cluster analysis discriminated the wheat varieties into two major clusters, one consisted of drought tolerant varieties and the other had all drought sensitive varieties. The present study showed that ISSR markers provide a valuable tool to study genetic variability in wheat varieties.

This paper is in continuation of our work on certain genuine hybrid operators in (Positivity (Under review)) [3]. First, we discuss some direct results in simultaneous approximation by these operators, e.g. pointwise convergence theorem, Voronovskaja-type theorem and an error estimate in terms of the modulus of continuity. Next, we estimate the rate of convergence for functions having a derivative that coincides a.e. with a function of bounded variation.

The challenging and competitive business environment in the global era has led to a change in the job demands and employee skills. Retention of talents is a challenge faced by the business organizations in today's competitive environment. The intelligent employers realized the importance of retaining best talents and started adapting strategies emphasizing retention management. HRM practices like fair pay, Flexi timings, attractive benefits, career growth, learning and development, healthy work environment, supportive-inspiring boss, motivated co workers, inspiring clients, recognition and respect may add to the feeling of belongingness and the interest of an employee to work in a great place. The subject of managing for employee retention involves a company's strategic actions to keep employees motivated and focused so that they remain employed and fully productive for the benefit of the organization.

In the present paper, we introduce the q-analog of the Stancu variant of Szász-Baskakov operators. We establish the moments of the operators by using the q-derivatives and then prove the basic convergence theorem. Next, the Voronovskaja type theorem and some direct results for the above operators are discussed. Also, the rate of convergence and weighted approximation by these operators in terms of modulus of continuity are studied. Then we obtain a point-wise estimate using the Lipschitz type maximal function. Lastly, we study the A-statistical convergence of these operators and also, in order to obtain a better approximation, we study a King type modification of the above operators. MSC:41A25, 26A15, 40A35.

Thirty patients with thalassemia major receiving repeated blood transfusion were studied to see their serum parathyroid hormone (PTH) and calcium status. Serum PTH, serum and 24 h urinary calcium, and serum alkaline phosphatase, phosphorus, and albumin-corrected calcium levels were determined. Half of these patients, in addition to transfusion, were also supplemented with vitamin D (60,000 IU for 10d) and calcium (1500 mg/day for 3 months). Serum PTH, and serum and 24 h urinary calcium concentrations of the patients receiving transfusions were found to be significantly reduced while their serum alkaline phosphatase, phosphorus, and albumin-corrected calcium levels were not significantly altered when compared to the respective mean values for the control group. Vitamin D and calcium supplementation significantly increased their serum PTH and calcium levels. Supplementations also increased urinary excretion of calcium. The results thus suggest that patients with thalassemia have hypoparathyroidism and reduced serum calcium concentrations that in turn were improved with vitamin D and calcium supplementation.

High temperature stress limits wheat production worldwide. Several studies reflect that genotypic variability exists for thermo-tolerance in wheat. In this study, genotypic varia-bility for thermo-tolerance was dissected at mo-lecular level. We accessed 20 selected bread wheat genotypes (10 thermo-tolerant and 10 thermo-sensitive) for genetic diversity analysis using random amplified polymorphic DNA (RAPD) and inter simple sequence repeats (ISSR) markers. In RAPD analysis, a total of 126 alleles were detected using 18 primers, among which 76 alleles (60.3%) were polymorphic. In ISSR analy-sis, using a total of 11 ISSR primers, 95 am-plified bands were obtained of which 46 (48.4%) were polymorphic. The average num-ber of polymorphic bands was higher in case of RAPDs (4.22) as compared to that in ISSRs (4.18). The clustering dendrogram generated by ISSR based similarity matrix, segregated thermo-tolerant and thermo-sensitive genotypes better than the RAPD based clustering dendrogram. One of ISSR primers (ISSR-41) amplified a ≈2800 bp band which was able to distinguish all the thermo-tolerant and sensitive genotypes except one. This marker identified in the study may po-tentially be used in marker assisted selection to develop thermo-tolerant wheat varieties.

Wheat is one of the most important staple food crop and is cultivated throughout the world. High temperature stress is one of the major constrains to wheat production worldwide. This study was undertaken with the objective to assess polymorphism among 14 genotypes (7 thermo-sensitive and 7 thermo-tolerant) of wheat. Genomic DNA of these wheat genotypes was amplified using 40 ISSR primers. Out of 40 primers screened, 26 ISSR primers which produced reproducible alleles were selected for allele scoring. Using these 26 ISSR primers, 187 amplified products were obtained of which 101 were polymorphic. ISSR analysis generated a moderate level of average polymorphism i.e. 52.97%. Average of amplified and polymorphic alleles per primer was calculated as 7.2 and 3.9, respectively. Overall size of PCR amplified products ranged between 220 bp and 3000 bp. Based on similarity matrix data, the value of similarity coefficient ranged from 0.73 to 0.87 with an average genetic similarity of 0.80. Cluster analysis based on ISSR markers discriminated all the wheat genotypes into two major clusters, one consisted of thermo-sensitive genotypes and other had all thermo-tolerant genotypes along with one thermo-sensitive genotype S1 (WH157). ISSR-24 amplified »2200bp band which was present in all 7 thermo-sensitive genotypes but absent in all thermo-tolerant genotypes. The above identified marker may potentially be used in marker assisted selection to develop thermo-tolerant wheat varieties.

Objectives: Hypersensitivity is a common clinical multietiological problem. Many desensitizing treatments are there to overcome hypersensitivity. The aim of this study was to evaluate the effect of different dentin-desensitizing treatments on the tensile bond strength of composite restoration. Materials and Methods: Twenty-four sound human molars were used. Enamel was wet abraded to expose flat dentin surfaces, polished with sandpaper. The specimens were then divided into three groups (n = 8) based on the type of dentin-desensitizing treatment given. The first group: G1 was the control group where no desensitizing agent was used. The second group: G2 was treated with desensitizing dentifrice containing a combination of potassium nitrate, triclosan, and sodium monoflorophosphate. The third group: G3 was treated with Er:YAG laser. Afterwards, the desensitized specimens were treated with one step self-etch adhesive according to manufacturer's instructions and composite microcylinders were packed. The specimens were then examined for tensile bond strength using universal tensile machine (KMI TM ). Results: Statistical analysis of the data obtained revealed the mean values for the tensile bond strengths were 10.2613 MPa, 5.9400 MPa and 6.3575 MPa for groups 1, 2 and 3, respectively. These values were statistically significantly different between groups pretreated with laser or dentifrice as compared to control group. Conclusions: Dentifrice and Laser pre-treated dentin has lower tensile bond strength with resin composites as compared to dentin that is untreated.