'Stealth' Technology: Proposed new method of interpretation of infrared ship signature requirements

A new method of deriving and defining requirements for the infrared signature of new ships is presented. The current approach is to specify the maximum allowed temperature or radiance contrast of the sheep with respect to its background

Measuring the electrical impedance of mouse brain tissue

We report on an experimental method to measure conductivity of cortical tissue. We use a pair of 5mm diameter Ag/AgCl electrodes in a Perspex sandwich device that can be brought to a distance of 400 microns apart. The apparatus is brought to uniform temperature before use. Electrical impedance of a sample is measured across the frequency range 20 Hz-2.0 MHz with an Agilent 4980A four-point impedance monitor in a shielded room. The equipment has been used to measure the conductivity of mature mouse brain cortex in vitro. Slices 400 microns in thickness are prepared on a vibratome. Slices are bathed in artificial cerebrospinal fluid (ACSF) to keep them alive. Slices are removed from the ACSF and sections of cortical tissue approximately 2 mm times 2 mm are cut with a razor blade. The sections are photographed through a calibrated microscope to allow identification of their cross-sectional areas. Excess ACSF is removed from the sample and the sections places between the electrodes. The impedance is measured across the frequency range and electrical conductivity calculated. Results show two regions of dispersion. A low frequency region is evident below approximately 10 kHz, and a high frequency dispersion above this. Results at the higher frequencies show a good fit to the Cole-Cole model of impedance of biological tissue; this model consists of resistive and non-linear capacitive elements. Physically, these elements are likely to arise due to membrane polarization and migration of ions both intra- and extra-cellularly.http://www.iupab2014.org/assets/IUPAB/NewFolder/iupab-abstracts.pd

Strategies for Engagement of Non-Traditional Students in Engineering-Related Courses

Project Goals Overview Goal #1: Increase students\u27 commitment to engineering pathways. Goal #2: Increase academic performance and persistence in engineering. Goal #3: Increase persistence of Veterans in engineering pathways. Research Questions How does students\u27 participation in peer-led team learning activities in online engineering courses correlate to their a) commitment to engineering, b) engineering identity, and c) self-efficacy. How do students in peer-led team learning activities compare to students in non-PLTL groups in terms of a) academic performance and b) persistence in engineering pathways

Future Directions of Space Education

The future of space operations graduate education is reliant on industry leaders’ contributions to help forecast the needs of the industry. The aim of the current study is to build consensus on the future direction of the space industry and generate new knowledge on what the industry expects to occur in the future of space studies education. This study documents the responses of 14 industry experts who currently or previously held highly visible senior leadership positions in a company or organization within the government or the commercial space industry and have extensive experience in a variety of management and leadership roles at space-related companies. The panelists’ qualitative responses were coded by themes related to the future of work for senior leadership in the industry. The findings from the consolidated responses included 20 educational and training content areas and nine shortcomings. The Delphi technique, a group consensus building process, was used to gain insight into the panelists’ responses (Dalkey, 1972). The research contributes to the body of knowledge on workforce education that can be used to inform faculty and administration in higher education on the relevance of program and curriculum content to address the future needs of the industry

Draft Genome Sequences of Helicobacter pylori Strains Isolated from Regions of Low and High Gastric Cancer Risk in Colombia

The draft genome sequences of six Colombian Helicobacter pylori strains are presented. These strains were isolated from patients from regions of high and low gastric cancer risk in Colombia and were characterized by multilocus sequence typing. The data provide insights into differences between H. pylori strains of different phylogeographic origins.National Institutes of Health (U.S.) (grant P01CA028842)National Institutes of Health (U.S.) (grant P01CA026731)National Institutes of Health (U.S.) (grant P30ES002109

Dual Requirement for Yeast hnRNP Nab2p in mRNA poly(A) Tail Length Control and Nuclear Export

Recent studies of mRNA export factors have provided additional evidence for a mechanistic link between mRNA 3′‐end formation and nuclear export. Here, we identify Nab2p as a nuclear poly(A)‐binding protein required for both poly(A) tail length control and nuclear export of mRNA. Loss of NAB2 expression leads to hyperadenylation and nuclear accumulation of poly(A)+ RNA but, in contrast to mRNA export mutants, these defects can be uncoupled in a nab2 mutant strain. Previous studies have implicated the cytoplasmic poly(A) tail‐binding protein Pab1p in poly(A) tail length control during polyadenylation. Although cells are viable in the absence of NAB2 expression when PAB1 is overexpressed, Pab1p fails to resolve the nab2Δ hyperadenylation defect even when Pab1p is tagged with a nuclear localization sequence and targeted to the nucleus. These results indicate that Nab2p is essential for poly(A) tail length control in vivo, and we demonstrate that Nab2p activates polyadenylation, while inhibiting hyperadenylation, in the absence of Pab1p in vitro. We propose that Nab2p provides an important link between the termination of mRNA polyadenylation and nuclear export

Post-LEP CMSSM Benchmarks for Supersymmetry

We introduce a set of CMSSM benchmark scenarios that take into account the constraints from LEP, Tevatron, $b \to s \gamma$, $g_\mu - 2$ and cosmology. The benchmark points are chosen to span the range of different generic possibilities, including focus-point models, points where coannihilation effects on the relic density are important, and points with rapid relic annihilation via direct-channel Higgs poles, as well as points with smaller sparticle masses. We make initial estimates of the physics reaches of different accelerators, including the LHC, and $e^+ e^-$ colliders in the sub- and multi-TeV ranges. We stress the complementarity of hadron and lepton colliders, with the latter favoured for non-strongly-interacting particles and precision measurements

Conformational heterogeneity of Savinase from NMR, HDX-MS and X-ray diffraction analysis

Background: Several examples have emerged of enzymes where slow conformational changes are of key importance for function and where low populated conformations in the resting enzyme resemble the conformations of intermediate states in the catalytic process. Previous work on the subtilisin protease, Savinase, from Bacillus lentus by NMR spectroscopy suggested that this enzyme undergoes slow conformational dynamics around the substrate binding site. However, the functional importance of such dynamics is unknown. Methods: Here we have probed the conformational heterogeneity in Savinase by following the temperature dependent chemical shift changes. In addition, we have measured changes in the local stability of the enzyme when the inhibitor phenylmethylsulfonyl fluoride is bound using hydrogen-deuterium exchange mass spectrometry (HDX-MS). Finally, we have used X-ray crystallography to compare electron densities collected at cryogenic and ambient temperatures and searched for possible low populated alternative conformations in the crystals. Results: The NMR temperature titration shows that Savinase is most flexible around the active site, but no distinct alternative states could be identified. The HDX shows that modification of Savinase with inhibitor has very little impact on the stability of hydrogen bonds and solvent accessibility of the backbone. The most pronounced structural heterogeneities detected in the diffraction data are limited to alternative side-chain rotamers and a short peptide segment that has an alternative main-chain conformation in the crystal at cryo conditions. Collectively, our data show that there is very little structural heterogeneity in the resting state of Savinase and hence that Savinase does not rely on conformational selection to drive the catalytic process

Proposed Post-LEP Benchmarks for Supersymmetry

We propose a new set of supersymmetric benchmark scenarios, taking into account the constraints from LEP, b to s gamma, g_mu - 2 and cosmology. We work in the context of the constrained MSSM (CMSSM) with universal soft supersymetry-breaking masses and assume that R parity is conserved. We propose benchmark points that exemplify the different generic possibilities, including focus-point models, points where coannihilation effects on the relic density are important, and points with rapid relic annihilation via direct-channel Higgs poles. We discuss the principal decays and signatures of the different classes of benchmark scenarios, and make initial estimates of the physics reaches of different accelerators, including the Tevatron collider, the LHC, and e+ e- colliders in the sub- and multi-TeV ranges. We stress the complementarity of hadron and lepton colliders, with the latter favoured for non-strongly-interacting particles and precision measurements. We mention features that could usefully be included in future versions of supersymmetric event generators