9,120 research outputs found
The Regulation of Prospore Membrane Shape in Saccharomyces Cerevisiae
The size and shape of a membrane is an important determinant in cell morphology. My work focuses on how membrane size and shape is determined, using the budding yeast S. cerevisiae as a model. During sporulation in S. cerevisiae, the diploid cell remodels its interior such that four spores are formed within an ascus. During this remodeling process, the prospore membrane is synthesized de novo and grows to surround each of the meiotic products. The prospore membrane is a double lipid bilayer and ultimately determines the sizes and shapes of the newly formed spores. My work focuses on the Pleckstrin homology domain protein Spo71 and its role in determining the size and shape of the prospore membrane. We have found that SPO71 is required for proper development of the prospore membrane. Cells lacking SPO71 have prospore membranes that are smaller than wild type cells and mislocalize septins, which are filament forming structural proteins. We have identified other genes that interact with SPO71, including SPO1, a putative phospholipase-B, and, SPO73. These genetic relationships provide important insight into the understanding of how various conserved domain-containing genes regulate membrane shape
Investigating the Effects of Tax Cuts on Capital Expenditures as an Alternative to Restore the United States Economy from the COVID-19 Pandemic
The Corona Virus has interrupted several years of strong economic expansion in the United States. In fact, it has disrupted the lives of every single person and organization in the world. After reaching its peak in mid-April, the rate of cases and related deaths has finally started to slow down. The U.S. Government passed three different pieces of legislation to address the effects of the virus. It is now considering legislation (referred to as Phase IV) to accelerate the return of the U.S. economy to its pre-pandemic level. Studies have shown that capital expenditures have been essential during periods of economic recovery. This study evaluates whether a reduction in corporate tax rates leads to an increase in capital expenditures by examining capital spending in two different time periods, one prior to the 2017 tax cut and one immediately following. The Tax Cuts and Jobs Act of 2017 significantly reduced corporate tax rates, from 35 to 21 percent, effective January 1, 2018 (Auerbach, 2018, Vol. 32, No. 4, Fall ). The results of this study will help the U.S. Congress determine whether a tax cut should be included in its upcoming Phase IV stimulus package which in turn could help restore the U.S. economy from the effects of the COVID-19 pandemic
Unitarity Triangle Analysis in the Standard Model and Sensitivity to New Physics
By using the most recent determinations of the several theoretical and
experimental input parameters, we update the Unitarity Triangle analysis in the
Standard Model and discuss the sensitivity to New Physics effects. We
investigate the interest of measuring with a better precision the various
physical quantities entering the Unitarity Triangle analysis and study in a
model independent way whether, despite the undoubted success of the CKM
mechanism in the Standard Model, the Unitarity Triangle analysis still allows
the presence of New Physics.Comment: Invited talk at the Workshop on the CKM Unitarity Triangle, IPPP
Durham, April 2003 (eConf C0304052). 9 pages LaTeX, 15 eps figures. Misprint
corrected and references adde
A Journal on the Web: What We Are Not, What We Do Not Want
In this paper we discuss the experience of publishing a journal in both a traditional and an electronic edition. In particular, we take into account our journal Doctor Virtualis, devoted to the history of medieval thought, trying to understand what the limitations and problems of electronic publishing are and where the paper edition is really different from the electronic one. Starting from our experience, we then try to better understand what electronic publishing actually is. We critically discuss the usual analogy between traditional publishing and electronic publishing, by proposing a new analogy between the web and the medieval cultural environment. This new analogy helps in understanding some complex processes on the web and in proposing new approaches to transform paper texts into electronic products. To this end, we show how rhetoric plays a crucial role in adapting the text to the medium and how new paradigms for text editing could help in finding a (preliminary) definition of electronic publishing
2000 CKM-Triangle Analysis A Critical Review with Updated Experimental Inputs and Theoretical Parameters
Within the Standard Model, a review of the current determination of the sides
and angles of the CKM unitarity triangle is presented, using experimental
constraints from the measurements of |\epsilon_K|, |V_{ub}/V_{cb}|, \Delta m_d
and from the limit on \Delta m_s, available in September 2000. Results from the
experimental search for {B}^0_s-\bar{B}^0_s oscillations are introduced in the
present analysis using the likelihood. Special attention is devoted to the
determination of the theoretical uncertainties. The purpose of the analysis is
to infer regions where the parameters of interest lie with given probabilities.
The BaBar "95 %, C.L. scanning" method is also commented.Comment: 44 pages (revised version
Constraints on new physics from the quark mixing unitarity triangle
The status of the Unitarity Triangle beyond the Standard Model including the
most recent results on Delta m_s, on dilepton asymmetries and on width
differences is presented. Even allowing for general New Physics loop
contributions the Unitarity Triangle must be very close to the Standard Model
result. With the new measurements from the Tevatron, we obtain for the first
time a significant constraint on New Physics in the B_s sector. We present the
allowed ranges of New Physics contributions to Delta F=2 processes, and of the
time-dependent CP asymmetry in B_s to J/Psi phi decays.Comment: 5 pages, 4 figures. v2: numerical error in Delta Gamma_s/Gamma_s
corrected. Plots and tables updated. v3: update after ICHEP06, final version
published in Phys Rev Letter
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