G-Bikes: Gettysburg Bike Share

The focus of this paper was to asses Gettysburg as possible location to implement a bike share program and ultimately to propose a framework for a successful program. We evaluated bike share programs across North America and created a list of criteria of successful programs. The second part of our data collection included a Google Forms survey which targeted three demographics, students, locals and tourists. We targeted our focus groups by posting on Facebook pages frequented by each demographic, as well as administering the survey in person with smart phones in Lincoln Square in Gettysburg. Our survey generated 134 responses, 86 of which were students, 27 locals, and 21 tourists. Our research showed that, demographically, successful programs occur in areas with high traffic from college students and tourists, as well as support from the local population. On the technical side, successful programs have 10-30 bikes per 10,000 residents with bike stations that range from 1-2 miles apart, averaging 4-8 trips per day, per bike. Our survey showed that a bike share program in Gettysburg would receive heavy support from our three demographics. It also showed that the largest concern from each demographic was bike related travel during the winter months which is consistent with the other programs we studied. Based on our research, we propose that the G-Bikes program should have 5 stations located at the top five intended locations of visitation, Gettysburg Town Center, Gettysburg College, Little Round Top, The Observation Tower, and on Steinwehr Avenue near the National Cemetery. Based off the overall population we recommend that the program start with a minimum of 20 bikes. We also recommend that the bike models follow the oBike specs from European bike share programs to maximize user convenience and minimize the threat of theft and vandalism. Through our study we determined Gettysburg\u27s unique niche as a small college town and tourist hub to be a possible location to implement a successful bike share program that implements many of the similar characteristics of other tourist destinations we studied

Electronic structure of lanthanide-doped bismuth vanadates:a systematic study by X-ray photoelectron and optical spectroscopies

\u3cp\u3e Monoclinic BiVO \u3csub\u3e4\u3c/sub\u3e has emerged in recent years as one of the most promising materials for photocatalytic evolution of oxygen under solar irradiation. However, it is in itself unable to phototcatalyze reduction of water to hydrogen due to the placement of the conduction band edge below the potential required for H \u3csub\u3e2\u3c/sub\u3e O/H \u3csub\u3e2\u3c/sub\u3e reduction. As a consequence, BiVO \u3csub\u3e4\u3c/sub\u3e only finds application in a hybrid system. Very recently, tetragonal lanthanide-doped BiVO \u3csub\u3e4\u3c/sub\u3e powders have been shown to be able to both reduce and to oxidize water under solar irradiation, but to date there has been no comprehensive study of the electronic properties of lanthanide-doped bismuth vanadates aimed at establishing the systematic trends in the electronic structure in traversing the lanthanide series. Here, the accessible family of lanthanide-doped BiVO \u3csub\u3e4\u3c/sub\u3e quaternary oxides of stoichiometry Bi \u3csub\u3e0.5\u3c/sub\u3e Ln \u3csub\u3e0.5\u3c/sub\u3e VO \u3csub\u3e4\u3c/sub\u3e (Ln = La to Lu, excluding Pm) has been studied by X-ray powder diffraction, X-ray photoemission spectroscopy, and diffuse reflectance optical spectroscopy. The compounds all adopt the tetragonal zircon structure, and lattice parameters decrease monotonically in traversing the lanthanide series. At the same time, there is an increased peak broadening in the diffraction patterns as the mismatch in ionic radius between Bi \u3csup\u3e3+\u3c/sup\u3e and the Ln \u3csup\u3e3+\u3c/sup\u3e ions increases across the series. Valence band X-ray photoemission spectra show that the final state 4f \u3csup\u3en-1\u3c/sup\u3e structure associated with ionization of lanthanide 4f \u3csup\u3en\u3c/sup\u3e states is superimposed on the valence band structure of BiVO \u3csub\u3e4\u3c/sub\u3e in the quaternary materials: in the case of the Ce-, Pr- and Tb-doped BiVO \u3csub\u3e4\u3c/sub\u3e , 4f-related states appear above the top of the main valence band of BiVO \u3csub\u3e4\u3c/sub\u3e and account for the small bandgap in the Ce compound. In all cases, the 4f structure is characteristic of the lanthanide element in the Ln(III) oxidation state. Vanadium 2p and lanthanide 3d or 4d core level photoelectron spectra of those compounds where the lanthanide may in principle adopt a higher (Ln = Ce, Pr, Tb) or lower (Ln = Eu, Yb) oxidation state further confirm the prevalence of the Ln(III) valence state throughout. The visible region optical properties of all samples were studied by diffuse reflectance spectroscopy, with a particular focus on the optical bandgap and the details of transitions associated with localized 4f states. Taken together, the results demonstrate the remarkable tunability of optical and electronic properties for these quaternary materials. \u3c/p\u3

Observations of the climate near the surface of Jezero over a half Mars year

International audiencePerseverance landed on Jezero with the most complete suite of environmental sensors ever sent to the surface of another planet. It combines the Mars Environmental Dynamics Analyzer (MEDA), the MastCam-Z and Engineering cameras, SuperCam spectrometers and, finally, the several microphones onboard the Mars 2020 rover. The most recent collection of atmospheric observations at Jezero and their interpretation are building an understanding of what physical processes drive the behavior of the Martian atmosphere near the surface of Jezero. We report on the observed Martian cycles of pressure, temperature, dust opacity with their physical aerosol properties, and the hydrological cycle at Jezero. These cycles have shown different behaviors on time scales from diurnal to seasonal and annual to other locations where we landed before. The differences illustrate the range of environmental processes that one can find near the red planet’s surface. We also report on the observed evolution of the near-surface boundary layer thermodynamics during the day and nighttime regimes

New insights into the genetic etiology of Alzheimer’s disease and related dementias

Characterization of the genetic landscape of Alzheimer’s disease (AD) and related dementias (ADD) provides a unique opportunity for a better understanding of the associated pathophysiological processes. We performed a two-stage genome-wide association study totaling 111,326 clinically diagnosed/‘proxy’ AD cases and 677,663 controls. We found 75 risk loci, of which 42 were new at the time of analysis. Pathway enrichment analyses confirmed the involvement of amyloid/tau pathways and highlighted microglia implication. Gene prioritization in the new loci identified 31 genes that were suggestive of new genetically associated processes, including the tumor necrosis factor alpha pathway through the linear ubiquitin chain assembly complex. We also built a new genetic risk score associated with the risk of future AD/dementia or progression from mild cognitive impairment to AD/dementia. The improvement in prediction led to a 1.6- to 1.9-fold increase in AD risk from the lowest to the highest decile, in addition to effects of age and the APOE ε4 allele

Common variants in Alzheimer’s disease and risk stratification by polygenic risk scores

Genetic discoveries of Alzheimer’s disease are the drivers of our understanding, and together with polygenetic risk stratification can contribute towards planning of feasible and efficient preventive and curative clinical trials. We first perform a large genetic association study by merging all available case-control datasets and by-proxy study results (discovery n = 409,435 and validation size n = 58,190). Here, we add six variants associated with Alzheimer’s disease risk (near APP, CHRNE, PRKD3/NDUFAF7, PLCG2 and two exonic variants in the SHARPIN gene). Assessment of the polygenic risk score and stratifying by APOE reveal a 4 to 5.5 years difference in median age at onset of Alzheimer’s disease patients in APOE ɛ4 carriers. Because of this study, the underlying mechanisms of APP can be studied to refine the amyloid cascade and the polygenic risk score provides a tool to select individuals at high risk of Alzheimer’s disease

Deep Underground Neutrino Experiment (DUNE) Near Detector Conceptual Design Report

International audienceThe Deep Underground Neutrino Experiment (DUNE) is an international, world-class experiment aimed at exploring fundamental questions about the universe that are at the forefront of astrophysics and particle physics research. DUNE will study questions pertaining to the preponderance of matter over antimatter in the early universe, the dynamics of supernovae, the subtleties of neutrino interaction physics, and a number of beyond the Standard Model topics accessible in a powerful neutrino beam. A critical component of the DUNE physics program involves the study of changes in a powerful beam of neutrinos, i.e., neutrino oscillations, as the neutrinos propagate a long distance. The experiment consists of a near detector, sited close to the source of the beam, and a far detector, sited along the beam at a large distance. This document, the DUNE Near Detector Conceptual Design Report (CDR), describes the design of the DUNE near detector and the science program that drives the design and technology choices. The goals and requirements underlying the design, along with projected performance are given. It serves as a starting point for a more detailed design that will be described in future documents