Stellar Populations in Bulges

We present line strengths in the bulges and inner disks of 38 galaxies in the local universe, including several galaxies whose bulges were previously identified as being disk-like in their colors or kinematics, to see if their spectral properties reveal evidence for secular evolution. We find that red bulges of all Hubble types are similar to luminous ellipticals in their central stellar populations. They have large luminosity-weighted ages, metallicities, and alpha/Fe ratios. Blue bulges can be separated into a metal-poor class that is restricted to late-types with small velocity dispersion and a young, metal-rich class that includes all Hubble types and velocity dispersions. Luminosity-weighted metallicities and alpha/Fe ratios are sensitive to central velocity dispersion and maximum disk rotational velocity. Red bulges and ellipticals follow the same scaling relations. We see differences in some scaling relations between blue and red bulges and between bulges of barred and unbarred galaxies. Most bulges have decreasing metallicity with increasing radius; galaxies with larger central metallicities have steeper gradients. Where positive age gradients (with the central regions being younger) are present, they are invariably in barred galaxies. The metallicities of bulges are correlated with those of their disks. While this and the differences between barred and unbarred galaxies suggest that secular evolution cannot be ignored, our results are generally consistent with the hypothesis that mergers have been the dominant mechanism responsible for bulge formation.Comment: 30 pages, 21 figures; submitted to MNRA

Rating Curve Development And Multivariate Statistical Analyses Of Stream Water Quality In Greensboro, North Carolina

A suite of regression models were tested for the construction of rating curves and constituent load estimation for 17 water quality parameters monitored at 16 stations regularly since 1999 by the City of Greensboro in North Carolina. Best models were selected based on the statistical evaluation within the framework of the LOAD ESTimator (LOADEST) model. The constituent prediction varied from the “true load†by –6% to 16% for Nitrate; -14% to +12% for Nitrite; -6% to 0% for Total Dissolved Solids (TDS); -2% to 9% for Total Kjeldahl Nitrogen (TKN); -22% to 9% for Total Phosphorus (TP); and -51% to 23% for Total Suspended Solids (TSS). There was a systematic bias towards under-prediction for TDS, TP and TSS whereas nitrate and TKN were over predicted and none for Nitrite. The predicted loads were compared with five interpolation methods (M1, M2, M3, M4 and M5) in the following pattern: for nitrate, TDS and TSS, load estimated by M3, M4 and M5 \u3e LOADEST \u3e M1 and M2; for nitrite, TKN and TP: LOADEST \u3e M3, M4 and M5 \u3e M1 and M2. Multivariate analyses used cluster analysis (CA), factor analysis (FA) and principal component analysis (PCA) on all parameters at all stations. CA grouped the water quality station into four spatially similar clusters. PCA/FA was applied on the entire dataset of entire watershed and spatially similar stations. Combination of FA/PCA and CA reduced the size of the dataset by 71% and represented the 64% of the total variance

Antiepileptics and Sound Perception Disorders

Epilepsy, a neurological health issue has been reported in all age groups and all countries. Anti-epileptic drugs have been reported to have many adverse events affecting different body parts and organs but their hazardous affect on a primary sensory organ is less known. In this mini review, we discuss thee impact of anti-epileptic medications on sound perception which adversely disrupts the quality of life

Psoriasis Awareness Month: Tackling the Common Autoimmune Disease

Psoriasis Awareness Month Guest Comment by Dr. Ashwini Bhaske

Identification of MHC Class II Binders/ Non-binders using Negative Selection Algorithm

The identification of major histocompatibility complex (MHC) class-II restricted peptides is an important goal in human immunological research leading to peptide based vaccine design. These MHC class–II peptides are predominantly recognized by CD4+ T-helper cells, which when turned on, have profound immune regulatory effects. Thus, prediction of such MHC class-II binding peptides is very helpful towards epitope-based vaccine design. HLA-DR proteins were found to be associated with autoimmune diseases e.g. HLA-DRB1*0401 with rheumatoid arthritis. It is important for the treatment of autoimmune diseases to determine which peptides bind to MHC class II molecules. The experimental methods for identification of these peptides are both time consuming and cost intensive. Therefore, computational methods have been found helpful in classifying these peptides as binders or non-binders. We have applied negative selection algorithm, an artificial immune system approach to predict MHC class–II binders and non-binders. For the evaluation of the NSA algorithm, five fold cross validation has been used and six MHC class–II alleles have been taken. The average area under ROC curve for HLA-DRB1*0301, DRB1*0401, DRB1*0701, DRB1*1101, DRB1*1501, DRB1*1301 have been found to be 0.75, 0.77, 0.71, 0.72, and 0.69, and 0.84 respectively indicating good predictive performance for the small training set

SurR9-C84A mutant nanocarrier and milk protein therapeutics for neurological disorders

 The current project revealed that the novel nanoformulation of SurR9-C84A was able to rescue the neurons following the Alzheimer’s related ß-amyloid toxicity and inflammation. In addition, bovine lactoferrin was found to have potential differentiating effect in the tumor cells and hence is a valuable therapeutic for strengthening the degenerating neurons

Flux free growth of large FeSe1/2Te1/2 superconducting single crystals by an easy high temperature melt and slow cooling method

We report successful growth of flux free large single crystals of superconducting FeSe1/2Te1/2 with typical dimensions of up to few cm. The AC and DC magnetic measurements revealed the superconducting transition temperature (Tc) value of around 11.5K and the iso-thermal MH showed typical type-II superconducting behavior. The lower critical field being estimated by measuring the low field iso-thermal magnetization in superconducting regime is found to be above 200 Oe at 0K.Comment: 15 pages text + Figs. Novel large cm size FeSe1/2Te1/2 superconducting crystal

MED23: a Mediator subunit's role in global gene transcription, regulation of craniofacial development and WNT signaling.

Expression of genes at the right time and place is crucial during adult homeostasis as well as embryonic development. Multicellular organisms regulate this spatiotemporal expression of genes by employing tissue specific transcription factors which bind to enhancer and repressor elements distant from the gene transcription start site. In embryonic development, most of the research understanding cell differentiation has focused on identifying such tissue specific transcription factors. What we do not understand clearly, is how these transcription factors that bind so far away from the gene promoter site influence the decision of RNA Pol II to transcribe or not transcribe. A recent discovery of a mega-dalton protein complex, called Mediator, has begun to answer this question. Mediator complex physically interacts with RNA Pol II and general transcription factors on one side and with transcription factors bound to enhancer/repressor sites on the other side. Mediator has thus been shown to act as a bridge that relays information between the transcription factors and RNA Pol II machinery and thus regulate gene expression. The various subunits of Mediator complex have been shown to interact with distinct transcription factors to regulate expression of specific genes. In this work, I describe the role of one such Mediator subunit, MED23. The role of MED23 during mammalian embryonic development was identified through a forward genetics screen done in the lab. Loss of med23 leads to mid-gestational lethality in mice embryos along with defects in craniofacial, neural and vascular development. We currently do not know the exact cause for embryonic lethality in med23 mutant embryos, but my results indicate that MED23 is crucial for endothelial cell-cell junction formation at E9.5, defects in which have previously been shown to affect embryonic survival. Specifically the formation of adherens and tight junctions between endothelial cells is affected in med23 mutant embryos. Analysis of neuronal defects in med23 mutant embryos suggests that MED23 is required during various steps of cranial placode development and this is regulated by MED23-mediated regulation of canonical WNT signaling. How and why loss of MED23 leads to defects in these specific tissues is currently unknown, but work with conditional mutant analysis as well as transcription factor-binding screens are underway to figure this out. My work thus highlights a unique link between general transcription co-factor, Mediator, and its subunit MED23 with development of neural, vascular and craniofacial tissues and a crucial signaling pathway, WNT signaling