1,928 research outputs found
Spontaneous R-Parity Breaking, Stop LSP Decays and the Neutrino Mass Hierarchy
The MSSM with right-handed neutrino supermultiplets, gauged B-L symmetry and
a non-vanishing sneutrino expectation value is the minimal theory that
spontaneously breaks R-parity and is consistent with the bounds on proton
stability and lepton number violation. This minimal B-L MSSM can have a
colored/charged LSP, of which a stop LSP is the most amenable to observation at
the LHC. We study the R-parity violating decays of a stop LSP into a bottom
quark and charged leptons--the dominant modes for a generic "admixture" stop. A
numerical analysis of the relative branching ratios of these decay channels is
given using a wide scan over the parameter space. The fact that R-parity is
violated in this theory by a vacuum expectation value of a sneutrino links
these branching ratios directly to the neutrino mass hierarchy. It is shown how
a discovery of bottom-charged lepton events at the LHC can potentially
determine whether the neutrino masses are in a normal or inverted hierarchy, as
well as determining the theta_23 neutrino mixing angle. Finally, present LHC
bounds on these leptoquark signatures are used to put lower bounds on the stop
mass.Comment: 13 pages, 2 figures, upgraded stop lower bound analysis, version
accepted by PL
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Oyster coast : a sense of place and change by the half-shell
The oyster has been a part of our diet for as long as we’ve settled where our rivers meet the sea — essentially as long as history has been recorded. Today, the Texas oyster fishery is a giant of an aquaculture industry with a lot of shifting gears. Particularly on Galveston Bay, where most of Texas’s oysters are harvested, recent environmental catastrophes, i.e. Hurricanes Ike and Harvey, as well as long-term effects of climate change have left a considerable impact on the region’s oyster supply that has kept commercial oysterman constantly adapting to meet market demand. In this report, I profile the oyster to give a glimpse into an aquaculture industry, a culinary tradition and the ever-changing Texas Gulf Coast where it all takes place. I discuss a bit of the history and processes of oyster cultivating and harvesting, as well as the politics of regulation by Texas Parks and Wildlife Department on the oyster reefs to look over the fragile natural resource. This piece is also accompanied by photographs and an audiovisual element.Journalis
Limitations of widely used high-risk human papillomavirus laboratory-developed testing in cervical cancer screening.
OBJECTIVE: To increase awareness of the limitations of high-risk human papillomavirus (hrHPV) laboratory-developed testing (LDT) widely used in US cervical cancer screening. METHODS AND RESULTS: A young woman in her 30s was diagnosed and treated for stage 1B1 cervical squamous cell carcinoma in which HPV 16 DNA was detected using polymerase chain reaction testing. Both 1 month before and 42 months before cervical cancer diagnosis, the patient had highly abnormal cytology findings; however, residual SurePath™ (Becton, Dickson and Company, Franklin Lakes, NJ) vial fluid yielded negative Hybrid Capture 2 (HC2; Qiagen NV, Hilden, Germany) hrHPV LDT results from each of the two specimens. This prompted questions to be asked concerning the performance characteristics of hrHPV LDT. A review of the available data indicates that (1) purification of DNA from SurePath specimens requires complex sample preparation due to formaldehyde crosslinking of proteins and nucleic acids, (2) HC2-SurePath hrHPV testing had not been Food and Drug Administration-approved after multiple premarket approval submissions, (3) detectible hrHPV DNA in the SurePath vial decreases over time, and (4) US laboratories performing HC2-SurePath hrHPV LDT testing are not using a standardized manufacturer-endorsed procedure. CONCLUSION: Recently updated cervical screening guidelines in the US recommend against the use of hrHPV LDT in cervical screening, including widely used HC2 testing from the SurePath vial. The manufacturer recently issued a technical bulletin specifically warning that use of SurePath samples with the HC2 hrHPV test may provide false negative results and potentially compromise patient safety. Co-collection using a Food and Drug Administration-approved hrHPV test medium is recommended for HPV testing of patients undergoing cervical screening using SurePath samples
Senior Recital: Timothy Nathaniel Marshall, bass-baritone
This recital is presented in partial fulfillment of requirements for the degree Bachelor of Music in Performance. Mr. Marshall studies voice with Oral Moses.https://digitalcommons.kennesaw.edu/musicprograms/1049/thumbnail.jp
Tensile Testing Environmental Chamber – Structural
Environmental chambers for tensile testing machines are used to study how a multitude of materials behave in extreme temperatures. These chambers provide the necessary information to innovate cutting edge technology for materials in fields such as aerospace. These chambers are often heavy and expensive requiring a significant amount of time and money just in the installation process alone. This report will serve to outline and define the design and fabrication of an environmental chamber, conducted by a team of four senior mechanical engineering students at California Polytechnic State University, San Luis Obispo. The goals of the project include a low-weight product, accurate and precise temperature changes within the chamber, visibility of the testing area, and ease of installation of the product on the tensile testing machine. This document provides an in-depth definition of the problem and a description of the background research conducted and presents the team’s initial design ideas as well as the concep
Combinations of isoform-targeted histone deacetylase inhibitors and bryostatin analogues display remarkable potency to activate latent HIV without global T-cell activation
AbstractCurrent antiretroviral therapy (ART) for HIV/AIDS slows disease progression by reducing viral loads and increasing CD4 counts. Yet ART is not curative due to the persistence of CD4+ T-cell proviral reservoirs that chronically resupply active virus. Elimination of these reservoirs through the administration of synergistic combinations of latency reversing agents (LRAs), such as histone deacetylase (HDAC) inhibitors and protein kinase C (PKC) modulators, provides a promising strategy to reduce if not eradicate the viral reservoir. Here, we demonstrate that largazole and its analogues are isoform-targeted histone deacetylase inhibitors and potent LRAs. Significantly, these isoform-targeted HDAC inhibitors synergize with PKC modulators, namely bryostatin-1 analogues (bryologs). Implementation of this unprecedented LRA combination induces HIV-1 reactivation to unparalleled levels and avoids global T-cell activation within resting CD4+ T-cells.</jats:p
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