The Higgs Seesaw Induced Neutrino Masses and Dark Matter

In this paper we propose a possible explanation of the active neutrino Majorana masses with the TeV scale new physics which also provide a dark matter candidate. We extend the Standard Model (SM) with a local U(1)' symmetry and introduce a seesaw relation for the vacuum expectation values (VEVs) of the exotic scalar singlets, which break the U(1)' spontaneously. The larger VEV is responsible for generating the Dirac mass term of the heavy neutrinos, while the smaller for the Majorana mass term. As a result active neutrino masses are generated via the modified inverse seesaw mechanism. The lightest of the new fermion singlets, which are introduced to cancel the U(1)' anomalies, can be a stable particle with ultra flavor symmetry and thus a plausible dark matter candidate. We explore the parameter space with constraints from the dark matter relic abundance and dark matter direct detection.Comment: 14 pages, 4 figure

Advanced Methodology Developments in Mixture Cure Models

Modern medical treatments have substantially improved cure rates for many chronic diseases and have generated increasing interest in appropriate statistical models to handle survival data with non-negligible cure fractions. The mixture cure models are designed to model such data set, which assume that studied population is a mixture of being cured and uncured. In this dissertation, I will develop two programs named smcure and NPHMC in R. The first program aims to facilitate estimating two popular mixture cure models: the proportional hazards (PH) mixture cure model and accelerated failure time (AFT) mixture cure model. The second program focuses on designing the sample size needed in survival trial with and without cure fractions based on the PH mixture cure model and standard PH model. The two programs have been tested by comprehensive settings and real data analysis and are now available for download from R CRAN. The third project in my dissertation will focus on the development of a new estimation method for the PH mixture cure model with competing risk data. The performance of proposed method has been evaluated by extensive simulation studies

Using First-Party Website Identity for Remarketing Attribution and Optimization

An improved method of evaluating and optimizing marketing campaigns utilizes first-party cookies to facilitate split testing. Users are assigned to control or treatment groups to assess the relative effectiveness of two different approaches. Marketers can produce precise, granular estimates of the ROI of a particular campaign by combining content optimization and marketing optimization in the context of evaluating campaign strategy

Understanding the Molecular Mechanism of Arsenic Tolerance and Accumulation in Pteris vittata

Arsenic is a toxic metalloid that is naturally occurring and widely distributed. The consumption of arsenic-contaminated food and water is threatening the health of millions of people in the world. The fern Pteris vittata is unusual in its ability to tolerate and hyperaccumulate exceptionally high concentrations of arsenic in its fronds. How P. vittata tolerates and accumulates arsenic is fundamentally different from that in angiosperms; however, the molecular mechanism underlying this trait in P. vittata is not well-defined. Because the haploid phase of the fern (the gametophyte) is morphologically simple, easy to grow and also tolerates and hyperaccumulates arsenic, the research described here focuses on the P. vittata gametophyte as a system for study. Combining differential gene expression (DEG) analysis using RNA-seq and knocking down gene expression by RNA interference, three genes (PvGAPC1, PvOCT4 and PvGSTF1) were identified that are necessary for arsenic tolerance in P. vittata gametophytes. Subcellular localization of the proteins encoded by these genes using live-cell imaging and biochemical enzyme kinetic analysis showed that the proteins encoded by all three genes localized in speckled patterns within the cell, and may be involved in sequestering arsenate as it moves from the cytoplasm into the vacuole, where arsenic is sequestered. cDNA libraries generated from P. vittata sporophytes were also sequenced and used to generate a comprehensive, high quality transcriptome of genes expressed in both gametophytes and sporophytes. By identifying genes that are expressed only in either the gametophyte or sporophyte generation, lignin biosynthesis and stomata differentiation genes that are only expressed in the sporophyte generation were discovered. This discovery may explain the lack of lignified cell types and stomata in the gametophyte. New phosphate transporter genes were also discovered, demonstrating that the transcriptome generated from this studyis an excellent resource for the identification of new genes potentially involved in arsenic tolerance and accumulation in P. vittata. Lastly, 3,292 genes that were differentially expressed (DEGs) in shoots or roots from P. vittata sporophytes treated with arsenic were identified from the transcriptome. Gene ontology analysis of these DEGs revealed clusters of genes that are involved in response to phosphate deficiency and transporter genes that are potentially important for arsenic trafficking in the roots and shoots of P. vittata sporophytes

ARABIDOPSIS MYOSIN IS INVOLVED IN THE DISTRIBUTION AND DYNAMIC BEHAVIOR OF THE CELLULOSE SYNTHASE COMPLEX

Plant cells are encased in cell walls which are important for the growth and development of the organism. Primary cell wall consists mainly of polysaccharides with cellulose as the most abundant component. In plant cells, cellulose is synthesized by a plasma membrane (PM) localized protein complex called the cellulose synthase complex (CSC). It was previously reported that disrupting normal actin organization resulted in a reduction of cellulose content in Arabidopsis dark-grown seedlings. Furthermore, actin was found to facilitate the delivery of CSC into the PM, and inferred to be involved in endocytosis. As a motor protein that translocates cargo along actin filaments, myosin plays an important role in organelle and vesicle trafficking. However, it is not known whether myosin is involved in regulating cellulose deposition or CSC behavior. Here, we used biochemical analysis to determine the cellulose content in Arabidopsis etiolated seedlings, and found a significantly decreased cellulose content in a myosin xi-1, xi-2, and xi-k triple knockout mutant (xi3KO), indicating that myosin is involved in cellulose deposition. To evaluate the molecular mechanism underlying the role of myosin in CSC trafficking, we characterized and employed a new plant myosin inhibitor

Exploring Biological Information: Document and discover Descriptions of Life

The human description and documentation of life has a long history as early as the ancient civilizations. For centuries, biological information, or information about life was preserved mostly as scientific article, illustrations, or permanent specimens. However, the discovery of the double helix structure of DNA in the 1950s, especially the launch of the Human Genome Project in the 1980s, significantly impacted the way we document information about life. This presentation will discuss the history and major formats of how biological information is documented and preserved, as well as tools to discover curated and archived biological information