2,979 research outputs found
Study of quiet turbofan STOL aircraft for short haul transportation
Conceptual designs of Quiet Turbofan STOL Short-Haul Transport Aircraft for the mid-1980 time period are developed and analyzed to determine their technical, operational, and economic feasibility. A matrix of aircraft using various high-lift systems and design parameters are considered. Variations in aircraft characteristics, airport geometry and location, and operational techniques are analyzed systematically to determine their effects on the market, operating economics, and community acceptance. In these studies, the total systems approach is considered to be critically important in analyzing the potential of STOL aircraft to reduce noise pollution and alleviate the increasing air corridor and airport congestion
Automatic assembly design project 1968/9: report of technical survey committee
An Industrial survey has been carried out to
determine the desired features of an automatic
as machine.
A questionnaire was circulated to industry and
the results of the 38% response obtained were
analysed and plotted. From these, conclusions
were drawn as to the industrial requirements of
an assembly machine
Study of aircraft in intraurban transportation systems, volume 1
An analysis of an effective short range, high density computer transportation system for intraurban systems is presented. The seven county Detroit, Michigan, metropolitan area, was chosen as the scenario for the analysis. The study consisted of an analysis and forecast of the Detroit market through 1985, a parametric analysis of appropriate short haul aircraft concepts and associated ground systems, and a preliminary overall economic analysis of a simplified total system designed to evaluate the candidate vehicles and select the most promising VTOL and STOL aircraft. Data are also included on the impact of advanced technology on the system, the sensitivity of mission performance to changes in aircraft characteristics and system operations, and identification of key problem areas that may be improved by additional research. The approach, logic, and computer models used are adaptable to other intraurban or interurban areas
Self-efficacy mediates the relationship between social norms and HPV vaccine intentions in undergraduate students
poster abstractHuman papillomavirus (HPV) is the most common sexually transmitted infection in the United States. The HPV vaccine reduces incidences of genital warts and certain cancers among both men and women. Unfortunately, many undergraduate students have not been vaccinated.
Previous research suggests students are more likely to report greater intentions to get vaccinated when others (e.g., friends, physicians) believe they should receive the vaccine; that is, greater social norms are associated with greater vaccine intentions. However, few studies have examined potential mediators of this association. Drawing from the Theory of Planned Behavior and the Health Belief Model, we hypothesized that social norms would be related to vaccine intentions through self-efficacy.
Undergraduate students (N=210) who had not received the HPV vaccine completed an online survey. Participants were predominately White (72%), female (67%), heterosexual (92%), and on average 19.9 years of age (SD=3.2). Forty-nine percent were in a romantic relationship, and 55% were sexually active within the past three months. Participants completed HPV vaccine specific measures, including social norms regarding vaccination, self-efficacy for vaccination, and vaccine intentions. Two mediation analyses (one per gender) were conducted to examine whether self-efficacy mediated the relationship between social norms and vaccine intentions. For women and men, greater social norms were related to greater self-efficacy, and greater selfefficacy was related to greater vaccine intentions (ps<0.05); additionally, social norms were indirectly related to vaccine intentions through self-efficacy (p<0.05). For women, after accounting for self-efficacy, social norms were still significantly related to intentions (p<0.05). For men, however, after accounting for self-efficacy, social norms were not significantly related to intentions (p=0.75).
Consistent with previous findings, social norms were positively related to vaccine intentions; however, we found that this association was mediated by self-efficacy. Future intervention studies should consider targeting social norms and improving students’ confidence in their ability to obtain the vaccine
Spatial-Distance Cues Influence Economic Decision-Making in a Social Context
Social distance (i.e., the degree of closeness to another person) affects the
way humans perceive and respond to fairness during financial negotiations.
Feeling close to someone enhances the acceptance of monetary offers. Here, we
explored whether this effect also extends to the spatial domain. Specifically,
using an iterated version of the Ultimatum Game in a within-subject design, we
investigated whether different visual spatial distance-cues result in
different rates of acceptance of otherwise identical monetary offers. Study 1
found that participants accepted significantly more offers when they were cued
with spatial closeness than when they were cued with spatial distance. Study 2
replicated this effect using identical procedures but different spatial-
distance cues in an independent sample. Importantly, our results could not be
explained by feelings of social closeness. Our results demonstrate that mere
perceptions of spatial closeness produce analogous–but independent–effects to
those of social closeness
Accretion-Induced Lithium Line Enhancements in Classical T Tauri Stars: RW Aur
It is widely accepted that much of the stochastic variability of T Tauri
stars is due to accretion by a circumstellar disk. The emission line spectrum
as well as the excess continuum emission are common probes of this process. In
this communication, we present additional probes of the circumstellar
environment in the form of resonance lines of low ionization potential
elements. Using a set of 14 high resolution echelle observations of the
classical T Tauri star (CTTS), RW Aur, taken between 1986 and 1996, we
carefully measure the continuum veiling at each epoch by comparing more than
500 absorption lines with those of an appropriate template. This allows us to
accurately subtract out the continuum emission and to recover the underlying
photospheric spectrum. In doing so, we find that selected photospheric lines
are enhanced by the accretion process, namely the resonance lines of LiI and
KI. A resonance line of TiI and a low excitation potential line of CaI also
show weak enhancements. Simple slab models and computed line bisectors lead us
to propose that these line enhancements are markers of cool gas at the
beginning of the accretion flow which provides an additional source of line
opacity. These results suggest that published values of surface lithium
abundances of classical T Tauri stars are likely to be overestimated. This
would account for the various reports of surface lithium abundances in excess
of meteoritic values among the extreme CTTS. Computing LTE lithium abundances
of RW Aur in a low and then high accretion state yields abundances which vary
by one order of magnitude. The low accretion state lithium abundance is
consistent with theoretical predictions for a star of this age and mass while
the high accretion state spectrum yields a super-meteoritic lithium abundance.Comment: 28 pages, 8 figures, accepted by Ap
The draft genome and transcriptome of Cannabis sativa
Background: Cannabis sativa has been cultivated throughout human history as a source of fiber, oil and food, and for its medicinal and intoxicating properties. Selective breeding has produced cannabis plants for specific uses, including high-potency marijuana strains and hemp cultivars for fiber and seed production. The molecular biology underlying cannabinoid biosynthesis and other traits of interest is largely unexplored. Results: We sequenced genomic DNA and RNA from the marijuana strain Purple Kush using shortread approaches. We report a draft haploid genome sequence of 534 Mb and a transcriptome of 30,000 genes. Comparison of the transcriptome of Purple Kush with that of the hemp cultivar 'Finola' revealed that many genes encoding proteins involved in cannabinoid and precursor pathways are more highly expressed in Purple Kush than in 'Finola'. The exclusive occurrence of \u3949-tetrahydrocannabinolic acid synthase in the Purple Kush transcriptome, and its replacement by cannabidiolic acid synthase in 'Finola', may explain why the psychoactive cannabinoid \u3949-tetrahydrocannabinol (THC) is produced in marijuana but not in hemp. Resequencing the hemp cultivars 'Finola' and 'USO-31' showed little difference in gene copy numbers of cannabinoid pathway enzymes. However, single nucleotide variant analysis uncovered a relatively high level of variation among four cannabis types, and supported a separation of marijuana and hemp. Conclusions: The availability of the Cannabis sativa genome enables the study of a multifunctional plant that occupies a unique role in human culture. Its availability will aid the development of therapeutic marijuana strains with tailored cannabinoid profiles and provide a basis for the breeding of hemp with improved agronomic characteristics.Peer reviewed: YesNRC publication: Ye
The Control, Development and Utilization of the Missouri River and its Tributaries
The speakers at this conference were Professors Condra, Caldwell, Stout, Phillips, Bengtson, and Gov. George L. Sheldon, with Dean Charles E. Bessey presiding. The principal object of the meeting was to make known reliable information in regard to the Missouri river, concerning which there is widespread interest and in some instances a tendency to magnify the future possibilities of the river. This paper is an account of the conference. It gives some of the thoughts that were emphasized at the symposium, reciting the facts as they were given by those who have investigated the respective phases of the theme.
GEOGRAPHIC CONDITIONS IN THE MISSOURI RIVER BASIN. BY G. E. CONDRA
EARLY NAVIGATION ON THE MISSOURI RIVER. BY H. W. CALDWELL
THE RELATIONS OF POWER AND IRRIGATION AT THE HEADWATERS OF THE MISSOURI TO FLOODS IN THE LOWER COURSES OF THE RIVER BY O. V. P. STOUT
THE RELATIONS OF FORES\u27fS TO RUN-OFF WATER. BY F. J. PHILLIPS
MEANDERS OF THE MISSOURI RIVER AND THEIR EFFECTS. BY. N. A. BENGTSON
WAYS AND MEANS. GOV. GEO. L, SHELDON
B lymphocytes contribute to indirect pathway T cell sensitisation via acquisition of extracellular vesicles
B cells have been implicated in transplant rejection via antibody‐mediated mechanisms and more recently by presenting donor‐antigens to T cells. We have shown in patients with chronic antibody‐mediated rejection that B cells control the indirect T cell alloresponses. To understand more about the role of B cells as antigen presenting cells for CD4⁺ T cell with indirect allospecificity, B cells were depleted in C57BL/6 mice, using an anti‐CD20 antibody, prior to receiving MHC‐class I‐mismatched (Kᵈ) skin. The absence of B cells at the time of transplantation prolonged skin graft survival. To study the mechanisms behind this observation, T cells with indirect allospecificity were transferred in mice receiving a Kᵈ skin transplant. T cell proliferation was markedly inhibited in the absence of recipient B cells, suggesting that B cells contribute to indirect pathway sensitisation. Furthermore, we have shown that a possible way in which B cells present alloantigens is via acquisition of MHC‐peptide complexes. Finally, we demonstrate that the addition of B cell depletion to the transfer of Tregs with indirect alloresponse further prolonged skin graft survival. This study supports an important role for B cells in indirect T cell priming and further emphasises the advantage of combination therapies in prolonging transplant survival
HIV-DNA Given with or without Intradermal Electroporation Is Safe and Highly Immunogenic in Healthy Swedish HIV-1 DNA/MVA Vaccinees: A Phase I Randomized Trial
We compared safety and immunogenicity of intradermal (ID) vaccination with and without electroporation (EP) in a phase I randomized placebo-controlled trial of an HIV-DNA prime HIV-MVA boost vaccine in healthy Swedish volunteers.HIV-DNA plasmids encoding HIV-1 genes gp160 subtypes A, B and C; Rev B; Gag A and B and RTmut B were given ID at weeks 0, 6 and 12 in a dose of 0.6 mg. Twenty-five volunteers received vaccine using a needle-free device (ZetaJet) with (n=16) or without (n=9) ID EP (Dermavax). Five volunteers were placebo recipients. Boosting with recombinant MVA-CMDR expressing HIV-1 Env, Gag, Pol of CRF01_AE (HIV-MVA) or placebo was performed at weeks 24 and 40. Nine of the vaccinees received a subtype C CN54 gp140 protein boost together with HIV-MVA.The ID/EP delivery was very well tolerated. After three HIV-DNA immunizations, no statistically significant difference was seen in the IFN-γ ELISpot response rate to Gag between HIV-DNA ID/EP recipients (5/15, 33%) and HIV-DNA ID recipients (1/7, 14%, p=0.6158). The first HIV-MVA or HIV-MVA+gp140 vaccination increased the IFN-γ ELISpot response rate to 18/19 (95%). CD4+ and/or CD8+ T cell responses to Gag or Env were demonstrable in 94% of vaccinees. A balanced CD4+ and CD8+ T cell response was noted, with 78% and 71% responders, respectively. IFN-γ and IL-2 dominated the CD4+ T cell response to Gag and Env. The CD8+ response to Gag was broader with expression of IFN-γ, IL-2, MIP-1β and/or CD107. No differences were seen between DNA vaccine groups. Binding antibodies were induced after the second HIV-MVA+/-gp140 in 93% of vaccinees to subtype C Env, with the highest titers among EP/gp140 recipients.Intradermal electroporation of HIV-DNA was well tolerated. Strong cell- and antibody-mediated immune responses were elicited by the HIV-DNA prime and HIV-MVA boosting regimen, with or without intradermal electroporation use.International Standard Randomised Controlled Trial Number (ISRCTN) 60284968
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