Ridge Regression and Lasso Estimators for Data Analysis

An important problem in data science and statistical learning is to predict an outcome based on data collected on several predictor variables. This is generally known as a regression problem. In the field of big data studies, the regression model often depends on a large number of predictor variables. The data scientist is often dealing with the difficult task of determining the most appropriate set of predictor variables to be employed in the regression model. In this thesis we adopt a technique that constraints the coefficient estimates which in effect shrinks the coefficient estimates towards zero. Ridge regression and lasso are two well-known methods for shrinking the coefficients towards zero. These two methods are investigated in this thesis. Ridge regression and lasso techniques are compared by analyzing a real data set for a regression model with a large collection of predictor variables

Road Access under Thirty Two Bridge Constructions in Karnali Highway: An Analysis of Socio-economic Impact in Community

The ground conditions of Nepal, road transport is not possible in all places. Without roads, development cannot accelerate and economic and social changes cannot occur. Construction of bridges to connect roads has become a very important issue. After the bridge is built on the road, the access of road transport to the settlements in those remote places becomes easier. It plays a role in making the daily life of the people living in that place easier as well as including the contribution of women in economic development. The bridge construction program is anticipating limited adverse impacts of land acquisition and resettlement confined to the area near the bridge works. Based on experience, adverse social impacts are likely to be temporary during the project work, such as temporary land leasing for the contractor operations. Access to the Bridge helps the beneficiaries. The construction provides a bridge, which provides for communities to access all weather. The bridge has accessibility, reducing travel time and improving access to economic centers and social services, whereas the community is easy for their livestock. They can easily market their agricultural products on the market. The impact of these bridges would increase the internal and external tourism market as well as assist those provinces. It is believed that after the construction of the bridge, the standard of living of the citizens living in that place will improve and the agricultural products produced by them will find the market easily. By saving time on the one hand and helping, in financial gain, on the other hand, the bridges constructed here will have a positive impact on the lives of the people

Collective clusterization effects in light heavy ion reactions

The collective clusterization process, proposed for intermediate mass fragments (IMFs, 4$<$A$\le$28, 2$<$Z$\le$14) emitted from the hot and rotating compound nuclei formed in low energy reactions, is extended further to include also the emission of light particles (LPs, A$\le$4, Z$\le$2) from the fusion-evaporation residues. Both the LPs and IMFs are treated as the dynamical collective mass motion of preformed clusters through the barrier. Compared to IMFs, LPs are shown to have different characteristics, and the predictions of our, so-called, dynamical cluster-decay model are similar to those of the statistical fission model.Comment: 4 pages, 3 figures, Conferenc

DIVERSITY, DISTRIBUTION AND ABUNDANCE OF LICHEN IN SIMILIPAL BIOSPHERE RESERVE, ODISHA

Lichens are organized symbionts that have their importance due to a potential indicator of the forest ecosystem. The lichen diversity of Odisha is not well explored as compared to the other phytogeographical region of India. Though the earlier study reported the occurrence of 252 lichen species from different parts of the state, it was limited to the northeast part of the Similipal Biosphere Reserve (SBR). The objective of the present study was to survey some unexplored areas of SBR, which revealed the occurrence of 84 species of lichens belonging to 38 families and 18 genera. Most of the lichens were found growing as phorophytes on the matured bark of the trees. The western part of the SBR is rich in lichen diversity as compared to the eastern part. Species frequency was found to be highest in the southwest part of the SBR, while the density and abundance were more or less similar within all the study sites. The correlation between frequency and density was found to be significant and insignificant between frequency and abundance

Characterization of color cross-talk of CCD detectors and its influence in multispectral quantitative phase imaging

Multi-spectral quantitative phase imaging (QPI) is an emerging imaging modality for wavelength dependent studies of several biological and industrial specimens. Simultaneous multi-spectral QPI is generally performed with color CCD cameras. However, color CCD cameras are suffered from the color crosstalk issue, which needed to be explored. Here, we present a new approach for accurately measuring the color crosstalk of 2D area detectors, without needing prior information about camera specifications. Color crosstalk of two different cameras commonly used in QPI, single chip CCD (1-CCD) and three chip CCD (3-CCD), is systematically studied and compared using compact interference microscopy. The influence of color crosstalk on the fringe width and the visibility of the monochromatic constituents corresponding to three color channels of white light interferogram are studied both through simulations and experiments. It is observed that presence of color crosstalk changes the fringe width and visibility over the imaging field of view. This leads to an unwanted non-uniform background error in the multi-spectral phase imaging of the specimens. It is demonstrated that the color crosstalk of the detector is the key limiting factor for phase measurement accuracy of simultaneous multi-spectral QPI systems.Comment: 16 pages, 8 figure

Vitamin B12 deficiency in patients of type 2 diabetes mellitus treated with metformin: a cross section observational study from a tertiary care centre in Sub-Himalayan region of North India

Background: Metformin is first line of treatment in type 2 diabetes mellitus (T2DM). It has been reported to be associated with vitamin B12 deficiency with variable results in various studies. The aim of our study is to correlate metformin use and vitamin B12 levels in patients of T2DM with high prevalence in Sub-Himalyan region of north India.Methods: The study was conducted from August 2017 to July 2018 enrolling 124 patients, aged 18 years and above with T2DM taking metformin treatment for &gt;4 months. Vitamin B12 levels were estimated and the levels &lt;200, 200-300 and &gt;300 pg/ml were defined as having definite deficiency, borderline deficiency and normal levels respectively.Results: A total of 124 patients included 66 (53.2%) male and 58 (46.8%) female patients with T2DM on metformin treatment. The mean vitamin B12 level was found significantly low, 176.23±60.96 pg/ml and 18 (14.5%) patients were found to have significant vitamin B12 deficiency and 8(6.5%) patients, borderline deficiency in longer duration of metformin use for &gt;10 years (p&lt;0.001). Vitamin B12 deficiency was found significantly more in 14 (11.3%) patients taking lower doses ≤1000 mg/day of metformin compared to higher doses, a negative correlation. Peripheral neuropathy was significantly present in 15.3% of patients in metformin induced vitamin B12deficiency.Conclusions: Vitamin B12 deficiency was found to be significantly correlated to longer duration of metformin treatment and neuropathy in T2DM but negatively correlated to higher doses of metformin. Therefore, we recommend the assessment and supplementation of vitamin B12 in metformin use in T2DM, compromising financial burden but not the outcome of its deficiency

Pyrenocarpous lichens in Goa with five new records to India

The pyrenocarpous lichens are the one which produces perithecial ascocarps. They are one of the prominent groups of lichens in tropical forests. Frequent incidence of pyrenocarpous taxa in lichen biota of Goa prompted us to take up the exclusive study of this group in the State. The study revealed the occurrence of 79 species belonging to 15 genera and seven families. The family Pyrenulaceae had the maximum number of 23 species, while 20 belonged to the family Porinaceae. In comparison to North Goa, South Goa is fairly well explored for lichens representing 71 species from 11 localities. The following five species are reported as new to India — Porina exserta, P. siamensis, Pyrenula dissimulans, P. pyrenastrospora and P. rinodinospora. With the addition of five new records, the Goa State now represents 165 species of lichens, out of which 48% is represented by pyrenocarpous lichens. The present study will be useful for monographic studies on pyrenocarpous lichens and for environmental monitoring studies in the area, as this can be considered as a key indicator species

Click chemistry inspired one-pot synthesis of 1,4-disubstituted 1,2,3-triazoles and their Src kinase inhibitory activity

Two classes of 1,4-disubstituted 1,2,3-triazoles were synthesized using one-pot reaction of α-tosyloxy ketones/α-halo ketones, sodium azide, and terminal alkynes in the presence of aq PEG (1:1, v/v) using the click chemistry approach and evaluated for Src kinase inhibitory activity. Structure–activity relationship analysis demonstrated that insertion of C6H5– and 4-CH3C6H4– at position 4 for both classes and less bulkier aromatic group at position 1 in class 1 contribute critically to the modest Src inhibition activity (IC50 = 32–43 μM) of 1,4-disubstituted 1,2,3-triazoles. [Refer to PDF for graphical abstract

Lichen synusiae in East Antarctica (Schirmacher Oasis and Larsemann Hills): substratum and morphological preferences

Antarctic terrestrial ecosystems experience some of the most extreme growth conditions, where plant distribution is determined by favourable environmental gradients of temperature and moisture along with micro-topography of habitats. Lichens are among the most tolerant symbiotic organisms which constitute dominant component in the terrestrial biota of Antarctica. There are various studies dealing with patterns of lichen diversity of various regions of Antarctica are done but in east Antarctica such studies are scanty. Lichen synusiae of Schirmacher Oasis and McLeod Island, Larsemann Hills, East Antarctica were studied in order to determine their morphological and substratum affinities. The Lichen synusiae of the study sites was represented by 71 species, 24 genera and 13 families in Schirmacher Oasis and 27 species, 18 genera and 10 families in McLeod Island, Larsemann Hills. Hierarchical cluster analysis of lichen communities on the basis of growth form diversity and substratum occurrence showed that crustose growth form and saxicolous (on rock, stones and moraines) habitat were the most preferred, in both study sites. The study presents a representative account of morphological and substratum preference patterns in lichen synusiae of east Antarctica, which can be of fundamental importance for future lichenological investigation in the region