Likelihood-Based Inference for Semi-Parametric Transformation Cure Models with Interval Censored Data

A simple yet effective way of modeling survival data with cure fraction is by considering Box-Cox transformation cure model (BCTM) that unifies mixture and promotion time cure models. In this article, we numerically study the statistical properties of the BCTM when applied to interval censored data. Time-to-events associated with susceptible subjects are modeled through proportional hazards structure that allows for non-homogeneity across subjects, where the baseline hazard function is estimated by distribution-free piecewise linear function with varied degrees of non-parametricity. Due to missing cured statuses for right censored subjects, maximum likelihood estimates of model parameters are obtained by developing an expectation-maximization (EM) algorithm. Under the EM framework, the conditional expectation of the complete data log-likelihood function is maximized by considering all parameters (including the Box-Cox transformation parameter $\alpha$) simultaneously, in contrast to conventional profile-likelihood technique of estimating $\alpha$. The robustness and accuracy of the model and estimation method are established through a detailed simulation study under various parameter settings, and an analysis of real-life data obtained from a smoking cessation study.Comment: 20 page

An overview of floral and faunal diversity in and around Barrackpore Rastraguru Surendranath College Campuses, West Bengal, India

The present survey based study involves the qualitative diversity of flora and fauna. The diversity assessment was carried out at two campuses of Barrackpore Rastraguru Surendranath College. This extensive study reveals the presence of 256 floral species and 165 faunal species in and around college campuses. The huge faunal diversity is mainly due to high level of floral diversity, which establishes the area as resource-rich habitat with promising reservoir of species. This is the very first effort in exploring the natural wealth of Barrackpore Rastraguru Surendranath College campuses. DOI: http://dx.doi.org/10.5281/zenodo.369591

Disformal transformations and the motion of a particle in semi-classical gravity

The approach to incorporate quantum effects in gravity by replacing free particle geodesics with Bohmian non-geodesic trajectories has an equivalent description in terms of a conformally related geometry, where the motion is force free, with the quantum effects inside the conformal factor, i.e., in the geometry itself. For more general disformal transformations relating gravitational and physical geometries, we show how to establish this equivalence by taking the quantum effects inside the disformal degrees of freedom. We also show how one can solve the usual problems associated with the conformal version, namely the wrong continuity equation, indefiniteness of the quantum mass, and wrong description of massless particles in the singularity resolution argument, by using appropriate disformal transformations.Comment: 18 Pages, LaTe

A mobile, scanning eye-safe lidar for the study of atmospheric aerosol particles and transport processes in the lower troposphere

A high-power eye-safe scanning aerosol lidar system in the ultraviolet wavelength region is introduced for the study of the optical properties of aerosol particles and transport processes in the atmosphere, especially in the atmospheric boundary layer (ABL). This system operates with an average power of 9 W in combination with a 40-cm scanner with a speed of up to 10° s-1. A modified version of the lidar inversion algorithm is developed for the retrieval of optical properties of aerosols from scanning lidar measurements. The lidar data can be analyzed with previously unachieved temporal and spatial resolution of 0.03 s and 3 m, respectively.Zur Untersuchung optischer Eigenschaften von Aerosolpartikeln und Transportprozessen in der Atmosphäre, speziell in der atmosphärischen Grenzschicht (atmospheric boundary layer, ABL), wird ein augensicheres Hochleistungs-Scanning-Lidarsystem im ultravioletten Wellenlängenbereich vorgestellt. Das System arbeitet mit einer durchschittlichen Leistung von 9 W in Kombination mit einem 40 cm Scanner mit einer Geschwindigkeit bis zu 10° s-1. Eine modifizierte Version des Lidar-Inversionsalgorithmus zur Rekonstruktion der optischen Eigenschaften von Aerosolpartikeln aus den Scanning-Lidar-Messungen wird entwickelt. Die Lidar-Daten können mit einer bisher nicht erreichten zeitlichen und räumlichen Auflösung von 0,03 s bzw. 3 m analysiert werden

ADOPTION STATUS AND FIELD LEVEL PERFORMANCE OF DIFFERENT PROTECTED STRUCTURES FOR VEGETABLE PRODUCTION UNDER CHANGING SCENARIO

Vegetable crops are short duration in nature and sudden changes in climatic parameters at any developmental phase can affect the normal growth, flowering, pollination, fruit development and subsequently decrease the crop yield. Protected structures can play important role to minimize the impact of climatic change effect. Farmers are gradually adopting different protected structures to combat the climatic vagaries and emerging challenges in vegetable production. To understand adoption and utilization pattern of protected structures, an investigation was carried out during 2011-2012 through questionnaire survey in different vegetable belt of the district. The study revealed that habit of adoption of protected structures namely agro-shade net house, poly-tunnel, poly-house and pro-tray have increased during last 5 years. Poly-tunnel was the most used structure utilized for raising vegetable seedling during rainy season. Seedling rising in pro-trays and crop production inside agro-shade net also gaining popularity among the farmers. Although poly-tunnel was the most adopted structure but the performance of poly-house was emerged as best structure in field condition. Additional investment and lack of knowledge for proper utilization were the major factors hindering the large scale adoption of protected structures