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Stevia rebaudiana Bertoni is a perennial herb, widely used as a natural sweetener around the globe. The key compounds responsible for its sweetness includes stevioside and rebaudioside-A. In order to improve these steviol glycosides, the present study was initiated to study the effect of induced mutagenesis on growth parameters, steviol glycosides and nuclear DNA content in Stevia rebaudiana Bertoni using ten doses of gamma-rays (5-100 kR). Healthy seeds of 'Madhuguna' variety of Stevia rebaudiana Bertoni developed and maintained at stevia breeding farm, Agrotechnology division, CSIR-Institute of Himalayan Bioresource Technology, Palampur (HP), India were irradiated with ten doses of gamma rays (600 seeds each/dose) ranging from 5 kR to 100 kR (i.e., 5, 10, 15, 20, 30, 40, 50, 60, 80 and 100 kR) using Co60 gamma irradiation chamber at CCS Haryana Agricultural University, Hisar, (Haryana), India. Significant variations were recorded for all the seedling traits studied while major impact was noticed on the seedling after reaching the cotyledonary stage and doses above 40 kR showed absolute mortality of the seedlings. Based on probit analysis, the optimum LD50 dose lies in the range of 20-23 kR. Glycosidic profiling of 296 mutants using high-performance liquid chromatography showed decreased total steviol glycoside content with increased radiation dose. Doses 5 kR and 10 kR, were found to be effective in increasing the overall glycosidic content. A total of 72 promising mutants were also screened for increased rebaudioside-A stevioside ratio. Comparison of nuclear DNA content using flow cytometry revealed a similar decrease in the total nuclear DNA content with increase in dosage of gamma rays. The average genome size at 5, 10, 15, 20 and 30 kR treatments were 2.72, 2.69, 2.68, 2.70 and 2.66 pg as compared to 2.72 pg in control. Mild dose of gamma rays (5 and 10 kR) in stevia were found to be effective in improving the mean steviol glycoside content and may be used in future stevia mutation programmes. [ABSTRACT FROM AUTHOR]

AbstractVery little attention has been paid by the authors for providing improved imputation methods under correlated measurement errors (CMEs) using various sampling designs. This article addresses several power ratio imputation methods and the resulting estimators under ranked set sampling (RSS) when CMEs are present. The mean square error (MSE) is developed to assess how well the suggested estimators work under CMEs. The effectiveness of the proposed imputation methods and corresponding resultant estimators is assessed by a comprehensive simulation utilizing an artificially generated population. Further, an application of the proposed imputation methods is also provided using real data from Sweden’s municipalities consisting of the total number of seats in 1982 in municipal council taken as study variable and the number of conservative seats in 1982 in municipal council taken as auxiliary variable. The CMEs might arise due to common surveyor biases if the same surveyor collects information on both the “total number of seats in municipal council” and “the number of conservative seats in that municipal council”. The simulation and real data results show that the proposed power ratio imputation methods outperform the mean, conventional ratio, and product imputation methods. [ABSTRACT FROM AUTHOR]

In surveys, successive sampling is generally considered to study the same characteristic from one occasion to another so that the change in characteristics over time can be further studied. This paper presents a class of estimators using a novel approach to estimate population mean on two occasions under successive sampling. We have carried out numerical study and simulation study to validate the significance of the proposed class and its members. We have used an optimum unmatched proportion of each class or estimator to compute their respective mean square error during simulation, while other studies considered some fixed value for unmatched units. For large population, the suggested estimation technique is always better for survey practitioners than others. [ABSTRACT FROM AUTHOR]

Abstract.This article suggested some sampling strategies allied with Searls (1964) for mean estimation on current occasions under an optimal random non response framework using auxiliary information. The characteristics of each class or estimator under their respective strategy have been studied under the optimum replacement policy. We have gauged losses, which are carried out to show the dominance over complete response classes like Singh and Vishwakarma (2007, 2009). Appropriate recommendations have been made to the survey researchers for their real-life practical applications. [ABSTRACT FROM AUTHOR]

Missing data is an obligatory phenomenon in most of the sample surveys and when it is not handled cautiously at beginning of the study, outcomes may result to substantial biases in the survey estimates. Retaining such evidences into cognizance, this paper proffers few possible improved imputation methods to figure out the problem of missing data at the starting of the study and proffers computation procedure of the population mean using simple random sampling. The characteristics of the proffered imputation methods are ascertained till first order approximation pursued by a computational study carried out using several existent and hypothetical data sets. The findings are turned out rather promising showing dominance over the existing imputation methods. Further, apposite advices have been forwarded to the survey professionals for practical applications. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we intend to utilize the multi auxiliary information available under RSS for the imputation of missing data. The mean imputation, regression imputation methods, and power transformation imputation method are identified as special cases of the proposed imputation methods. These methods are dominated by the proposed imputation methods. The theoretical comparison provides the dominance conditions of the proposed imputation methods over their conventional counterparts. In support of the theoretical findings, a simulation study is considered over a hypothetically generated population. Furthermore, some real data examples are also provided to generalize the simulation results. [ABSTRACT FROM AUTHOR]

In survey sampling, several estimation procedures have been proffered by various prominent authors to compute the impact of measurement errors (ME) but the impact of correlated measurement errors (CME) has been computed only by Shalabh and Tsai [Ratio and product methods of estimation of population mean in the presence of correlated measurement errors. Commun Stat Simul Comput. 2016;46(7):5566–5593]. This study provides a novel approach to compute the impact of CME through some logarithmic-type estimators using simple random sampling (SRS). The properties of the proffered estimators have been studied and compared with the properties of the conventional estimators. A numerical study and a broad spectrum simulation study are accomplished over real and artificially generated populations to support the theoretical results. [ABSTRACT FROM AUTHOR]

The essence of this paper is to propose some efficient combined and separate classes of estimators for estimating population mean Y ¯ under stratified simple random sampling. The bias and mean square error of the proposed classes of estimators are obtained. The proposed estimators are theoretically justified over the conventional mean estimator, classical ratio and regression estimators, Kadilar and Cingi estimators, Shabbir and Gupta estimators, Singh and Vishwakarma estimators, Koyuncu and Kadilar estimators, Singh and Solanki estimator, Yadav et al. estimator, Solanki and Singh estimator and Shahzad et al. estimator. The theoretical findings are extended with a simulation study accomplished over some artificially generated symmetric and asymmetric populations. [ABSTRACT FROM AUTHOR]

This paper proposes some optimal classes of estimators under ranked set sampling. We have acquainted some modifications of the difference and ratio type estimators under ranked set sampling, considered by various authors like Hansen et al., Srivastava, and Walsh in simple random sampling. We have demonstrated that the efficiency of the proposed optimal classes of estimators are always better than the other existing estimators. The theoretical results have been supported by a simulation study carried out over an artificially generated population. [ABSTRACT FROM AUTHOR]

In this article, we propose additive shared gamma frailty model and additive shared inverse Gaussian frailty model with Lindley as baseline distribution to analyze the infectious disease data set of McGilchrist and Aisbett. The Bayesian approach of Markov Chain Monte Carlo technique was employed to estimate the parameters involved in the models. A simulation study was also carried out to compare the true values and estimated values of the parameters. Comparison of proposed models and the existing models was also done by using Bayesian information criteria such as BIC, WBIC and Bayes factor. A better model was also recommended for infectious disease data. [ABSTRACT FROM AUTHOR]

This paper introduces some new ratio- and difference-type estimators of the population variance in the presence of random non-response based on Searls (The utilization of a known coefficient of variation in the estimation procedure. J Am Stat Asso. 1964;59:1225–1226) philosophy. The proposed ratio- and difference-type estimators remain better than the estimators obtained by Ahmeda et al. (Estimation of finite population variance in presence of random non-response using auxiliary variables. Infr Mang Sci. 2005;16(2):73–82) in the presence of random non-response using auxiliary variables. The properties (bias and mean square error) of the proposed estimators presented were derived up to the first-order approximation using the Taylor series approach. Conditions for which the new estimators more efficient than other estimators considered in the study were also established. Numerical examples were conducted, and the results revealed that the proposed class of estimators is more efficient than existing estimators. [ABSTRACT FROM AUTHOR]

The current trends of consumer-driven demands for natural therapeutics and the availability of evidence-based phytopharmaceuticals from traditional knowledge has once again brought the medicinal plants into forefront of health. In 2019, World Health Organization global report on traditional and complementary medicine has also substantiated the revival of herbal medicine including its convergence with conventional medicine for the management and prevention of diseases. It means these industries need plenty of plant materials to meet the unprecedented demands of herbal formulations. However, it is pertinent to mention here that around 70–80% medicinal plants are sourced from the wild and most of such highly acclaimed plants are listed under Rare, Endangered and Threatened species by IUCN. Additionally, over 30% traditional health formulations are based on underground plant parts, which lead to the uprooting of plants. Overharvesting from limited plant populations, meager conventional cultivation and a rising fondness for natural products exerting enormous pressure on natural habitats. Therefore, the nondestructive means of phytochemical production employing biotechnological tools could be used for sustainable production and consumption patterns. In recent years, a number of reports described the use of adventitious roots induced under in vitro conditions for the extraction of phytochemicals on a sustainable basis. In this article, efforts are made to review recent developments in this area as well as understand the induction mechanisms of adventitious roots, their in vitro cultivation, probable factors that affect the growth and metabolite production, and assess the possibility of industrial scale production to meet the rising demands of natural herbs. [ABSTRACT FROM AUTHOR]

The Greater Lizardfish, Saurida tumbil, forms a significant fishery in the demersal trawls along the west coast of India. But, the information regarding the stock structure of this species is scarce. In the present study, the morphology of fish, otolith shape, meristic traits and mt-DNA D-loop region were used to delineate the stocks collected from the west coast of India. Samples were collected between October to November 2018 from three major fish landing centres namely Mumbai, Mormugao and Kochi. Truss network analysis and otolith shape indices revealed the morphological divergence for body and otolith shape among the sampling regions. However, meristic traits and D-loop sequences of mitochondrial DNA could not show variation among the stocks, suggesting the existence of a single panmictic population of S. tumbil. The results of the present study are useful to formulate the stock-specific management measures for S. tumbil along the west coast of India. [ABSTRACT FROM AUTHOR]

The present study is an attempt to equip a strategy with a cost-effective computational approach when non response is present under two occasion sampling. We have applied our computational cost strategy over Choudhary et al. (2004)'s non response setup for fixed precision and evaluated cost. In addition, we have also computed variance for some fixed cost. We have discussed the aforementioned procedure for three cases as when there is non response present on both occasions, first occasion and second occasion. A numerical illustration is demonstrated for validation of improved cost methodology where we also work out with optimum unmatched or matched fraction while Choudhary et al. (2004) do not provide the direct optimal result. [ABSTRACT FROM AUTHOR]

This paper introduces some improved methods of imputation using higher order moment of an auxiliary variable while imputing missing values. The performance of the proposed imputation methods are investigated relative to the methods proposed by Mohamed, Sedory, and Singh (2016) and Bhushan and Pandey (2016, 2018). A comparative study has been carried out and it has been shown that the proposed methods perform better in comparision to methods proposed by Mohamed, Sedory, and Singh (2016) and Bhushan and Pandey (2016, 2018). The theoretical findings are supported by numerical study on two real populations and a simulation study using hypothetical population. [ABSTRACT FROM AUTHOR]

In this article, we have considered three different shared frailty models under the assumption of generalized Pareto Distribution as baseline distribution. Frailty models have been used in the survival analysis to account for the unobserved heterogeneity in an individual risks to disease and death. These three frailty models are with gamma frailty, inverse Gaussian frailty and positive stable frailty. Then we introduce the Bayesian estimation procedure using Markov chain Monte Carlo (MCMC) technique to estimate the parameters. We applied these three models to a kidney infection data and find the best fitted model for kidney infection data. We present a simulation study to compare true value of the parameters with the estimated values. Model comparison is made using Bayesian model selection criterion and a well-fitted model is suggested for the kidney infection data. [ABSTRACT FROM AUTHOR]

This article proposes various Searls-type ratio imputation methods (STRIM) on the lines of Ahmed et al. (2006). It is a well-known fact that the optimal ratio type estimator attains the MSE of regression estimator (or optimal difference estimator) but while using Searls-type transformation (STT) (Searls (1964)) this may not always happen. These STRIM are shown to perform better than the imputation procedures of Ahmed et al. (2006). The STRIM may even outperform the Searls type difference imputation methods (STDIM) proposed by us in our earlier work, Bhushan and Pandey (2016). This study is concluded with the numerical study along with the theoretical comparison. [ABSTRACT FROM AUTHOR]

Lupus nephritis and renal polyarteritis nodosa (PAN) are two distinct disorders that rarely overlap. Herein, we describe a patient who was initially diagnosed with lupus nephritis based on her clinical presentation, proteinuria, hematuria, positive anti-nuclear antibody, and a kidney biopsy. A month later, the patient presented with left flank pain and weakness. A CT scan of the abdomen and pelvis showed a perinephric hematoma and the renal arteriogram revealed numerous microaneurysms within the kidney consistent with renal PAN. This case elucidates the diagnostic and management dilemmas that confront physicians taking care of patients with overlapping features of lupus nephritis and renal PAN and also points to the possible role of lupus nephritis in pathogenesis of renal PAN. [ABSTRACT FROM PUBLISHER]

Shikonins are commercially important secondary compounds, known for array of biological activities such as antimicrobial, insecticidal, antitumor, antioxidants, etc. These compounds are usually colored and therefore have application in food, textiles and cosmetics. Shikonin and its derivatives, which are commercially most important of the naphthoquinone pigments, are distributed among members of the family Boraginaceae. These include different species of Lithospermum, Arnebia, Alkanna, Anchusa, Echium and Onosma. The growing demand for plant-based natural products has made this group of compounds one of the enthralling targets for their in vitro production. The aim of this review is to highlight the recent progress in production of shikonins by various biotechnological means. Different methods of increasing the levels of shikonins in plant cells such as selection of cell lines, optimization of culture conditions, elicitation, in situ product removal, genetic transformation and metabolic engineering are discussed. The experience of different researchers working worldwide on this aspect is also considered. Further, to meet market demand, the needs for continuous and reliable production systems, as well as future prospects, are included. [ABSTRACT FROM AUTHOR]

Clematis gouriana(Ranunculaceae), a perennial herb, is used by the local inhabitants of the western Himalayan region for its medicinal properties. Major bioconstituents ofC. gourianaleaves using different solvent extracts were obtained and analysed. The results revealed promising contents of phenolics (from 18.19 ± 0.10 to 22.17 ± 0.10 mg g− 1) as gallic acid and flavonoids (from 2.83 ± 0.01 to 6.52 ± 0.08 mg g− 1) as quercetin equivalent in different extracts. Aqueous acetone extract showed higher antioxidant activity with IC50value of 129.11 and 25.35 μg mL− 1against DPPH and ABTS free radicals, respectively. Antioxidant yield ranged from 16.87 ± 0.27 to 24.48 ± 0.13 mg g− 1of Trolox equivalent in different extracts as measured by the FRAP assay. Furthermore, ethylacetate extract exhibited strongin vitrocytotoxicity against Chinese hamster ovary and glioma cell lines. Proximate composition (proteins, fats, ash and minerals) ofC. gourianaleaves was also assessed. Results demonstrated the potential ofC. gourianabioconstituents as nutraceuticals. [ABSTRACT FROM PUBLISHER]

Bioassay-guided fractionation of the fruits of Piper longum afforded two new minor amides, piperlongimin A (2) [2E-N-isobutyl-hexadecenamide] and piperlongimin B (4) [2E-octadecenoylpiperidine] together with five known compounds with moderate cytotoxic activity. The structures were elucidated on the basis of spectroscopic evidences. All these compounds inhibited cell proliferation of human leukemia, HL-60 cell lines, and displayed major apoptosis-inducing effects. [ABSTRACT FROM AUTHOR]

Aim: Tamoxifen is a nonsteroidal estrogen receptor modulator indicated in the treatment of breast cancer. Apoptosis has been reported to be a major mechanism for its antitumor effect. Tamoxifen has also shown significant potential in treating various dermatological disorders including psoriasis, characterized by hyperproliferation of epidermal keratinocytes. An endeavor was made in the current studies to investigate the potency of vesicle-encapsulated tamoxifen on human epidermal keratinocyte cell lines. Methods: Drug was encapsulated in the phospholipid-based vesicular systems, namely, conventional liposomes and flexible-membrane liposomes. In vitro cytotoxicity evaluation of the formulations was carried out employing MTT cell proliferation assay. Results: A composition-dependent strong inhibition in the viability of epidermal keratinocyte cells was observed. Conclusion: The encouraging findings of this work construe immense potential of the tamoxifen-encapsulated vesicular systems in the management of psoriasis. [ABSTRACT FROM AUTHOR]

Tamoxifen is a nonsteroidal estrogen-receptor modulator widely used in the treatment of breast cancer. Apoptosis has been reported to be a major mechanism for its antitumor effect. In the current studies, an endeavor was made to investigate the efficacy of vesicularly encapsulated tamoxifen on human breast cancer MCF-7 cells. Phospholipid-based vesicular systems viz. conventional liposomes and elastic-membrane liposomes were employed to encapsulate the drug. The MTT colorimetric assay was used to determine the efficacy of the tested formulations. The results demonstrated composition-dependent strong inhibition in the viability of MCF-7 cells with encapsulated tamoxifen vis-à-vis free drug. The encouraging findings from the current work construe immense potential of the lipid-based vesicular systems in the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

The growth of horticulture industries worldwide has generated huge quantities of fruit wastes (25%-40% of the total fruits processed). These residues are generally a good source of carbohydrates, especially cell wall polysaccharides and other functionally important bioactive molecules such as proteins, vitamins, minerals and natural antioxidants. “Apple pomace” is a left-over solid biomass with a high moisture content, obtained as a by-product during the processing of apple fruits for juice, cider or wine preparation. Owing to the high carbohydrate content, apple pomace is used as a substrate in a number of microbial processes for the production of organic acids, enzymes, single cell protein, ethanol, low alcoholic drinks and pigments. Recent research trends reveal that there is an increase in the utilization of apple pomace as a food processing residue for the extraction of value added products such as dietary fibre, protein, natural antioxidants, biopolymers, pigments and compounds with unique properties. However, the central dogma is still the stability, safety and economic feasibility of the process(s)/product(s) developed. This review is mainly focused on assessing recent research developments in extraction, isolation and characterization of bioactive molecules from apple pomace, along with their commercial utilization, in food fortification. [ABSTRACT FROM AUTHOR]