452 research outputs found
Sociodemographic Factors Associated with AIDS Knowledge in a Random Sample of University Students
A telephone survey was used to assess knowledge of the transmission, prevalence, and infectivity of acquired immunodeficiency syndrome (AIDS), and the safety of casual contact among 214 randomly selected university students. Males were more knowledgeable than females overall (odds ratio [OR], men/women = 4.8). Although most students understood the dangers of unprotected sex and intravenous needle sharing, up to 30% believed some kinds of casual contact (e.g., shared eating utensils) can transmit AIDS. Older students (≥ 23 yrs) were more knowledgeable than those 17 to 19 years old about the safety of casual contact (OR = 3.8). Students are in need of education programs that stress the ways AIDS is not transmitted. Since most students identified newspapers and television as their main sources of information, these may be effective vehicles for education efforts.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73095/1/j.1525-1446.1991.tb00654.x.pd
Friedmann-like equations for High Energy Area of Universe
In this paper, evolution of the high energy area of universe, through the
scenario of 5 dimensional (5D) universe, has been studied. For this purpose, we
solve Einstein equations for 5D metric and 5D perfect fuid to derive
Friedmann-like equations. Then we obtain the evolution of scale factor and
energy density with respect to both space-like and time-like extra dimensions.
We obtain the novel equations for the space-like extra dimension and show that
the matter with zero pressure cannot exist in the bulk. Also, for dark energy
fuid and vacuum fluid, we have both accelerated expansion and contraction in
the bulk.Comment: 9 pages, Accepted to publication in IJTP 26 June 2012. arXiv admin
note: substantial text overlap with arXiv:1202.497
What causes organizations to fail? A review of literature to inform future food sector (management) research
Background
Organizational failure in food markets is a potential threat to food security. Thus, a greater understanding of the factors that influence organizational failure and reduce supply chain resilience is essential to underpin agile and dynamic food supply chains.
Scope and approach
The aim of this paper is to contribute to the understanding of system level factors that influence organizational failure in food supply chains in order to conceptualize the horizontal and vertical interaction of such factors at the three levels described: the micro system, the meso system and the macro system level. A systematic review, based on a specific search strategy, incorporated articles from the fields of management, business and economics research. Whilst 616 articles were initially identified, only 41 of these were within the established inclusion criteria and reviewed. A model of organizational failure, determined here as “The House of Cards Model”, is developed, that can then be empirically tested in further research.
Key findings and conclusions
A hierarchy was developed to contextualize the factors deemed to be of influence. The macro (external environment) level includes criteria such as economic conditions, formal institutions, government policies, competitors and rumors. The factors addressed in the meso (organizational) level include organization age and size, location, property structure, client, supplier and shareholder relationships, financial resources, physical resources, human resources and succession process. At the micro (individual) level the managers’ skill, characteristics, actions and mindset are of influence. This paper contributes to advancing the debate and underpins further empirical research on organizational failure in food supply chains
Physical Characterization of an Unlensed, Dusty Star-forming Galaxy at z = 5.85
We present a physical characterization of MM J100026.36+021527.9 (a.k.a. "Mambo-9"), a dusty star-forming galaxy (DSFG) at z = 5.850 \ub1 0.001. This is the highest-redshift unlensed DSFG (and fourth most distant overall) found to date and is the first source identified in a new 2 mm blank-field map in the COSMOS field. Though identified in prior samples of DSFGs at 850 \u3bcm to 1.2 mm with unknown redshift, the detection at 2 mm prompted further follow-up as it indicated a much higher probability that the source was likely to sit at z > 4. Deep observations from the Atacama Large Millimeter and submillimeter Array (ALMA) presented here confirm the redshift through the secure detection of 12CO(J = 6\u21925) and p-H2O (21,1 \u2192 20,2). Mambo-9 is composed of a pair of galaxies separated by 6 kpc with corresponding star formation rates of 590 M o\u2d9 yr-1 and 220 M o\u2d9 yr-1, total molecular hydrogen gas mass of (1.7 \ub1 0.4)
7 1011 M o\u2d9, dust mass of (1.3 \ub1 0.3)
7 109 M o\u2d9, and stellar mass of (3.2-1.5+1.0)
7 109 M o\u2d9. The total halo mass, (3.3 \ub1 0.8)
7 1012 M o\u2d9, is predicted to exceed 1015 M o\u2d9 by z = 0. The system is undergoing a merger-driven starburst that will increase the stellar mass of the system tenfold in \u3c4 depl = 40-80 Myr, converting its large molecular gas reservoir (gas fraction of 96-2+1) into stars. Mambo-9 evaded firm spectroscopic identification for a decade, following a pattern that has emerged for some of the highest-redshift DSFGs found. And yet, the systematic identification of unlensed DSFGs like Mambo-9 is key to measuring the global contribution of obscured star formation to the star formation rate density at z \u2a86 4, the formation of the first massive galaxies, and the formation of interstellar dust at early times ( 721 Gyr)
Response of Wheat Fungal Diseases to Elevated Atmospheric CO2 Level
Infection with fungal pathogens on wheat varieties with different levels of resistance was
tested at ambient (NC, 390 ppm) and elevated (EC, 750 ppm) atmospheric CO2 levels in the
phytotron. EC was found to affect many aspects of the plant-pathogen interaction. Infection
with most fungal diseases was usually found to be promoted by elevated CO2 level in susceptible
varieties. Powdery mildew, leaf rust and stem rust produced more severe symptoms on
plants of susceptible varieties, while resistant varieties were not infected even at EC. The penetration
of Fusarium head blight (FHB) into the spike was delayed by EC in Mv Mambo, while
it was unaffected in Mv Regiment and stimulated in Mv Emma. EC increased the propagation
of FHB in Mv Mambo and Mv Emma. Enhanced resistance to the spread of Fusarium within
the plant was only found in Mv Regiment, which has good resistance to penetration but poor
resistance to the spread of FHB at NC. FHB infection was more severe at EC in two varieties,
while the plants of Mv Regiment, which has the best field resistance at NC, did not exhibit a
higher infection level at EC.
The above results suggest that breeding for new resistant varieties will remain a useful
means of preventing more severe infection in a future with higher atmospheric CO2 levels
Increasing source to image distance for AP pelvis imaging – impact on radiation dose and image quality
Aim: A quantative primary study to determine whether increasing source to image distance (SID), with
and without the use of automatic exposure control (AEC) for antero-posterior (AP) pelvis imaging, reduces
dose whilst still producing an image of diagnostic quality.
Methods: Using a computed radiography (CR) system, an anthropomorphic pelvic phantom was positioned
for an AP examination using the table bucky. SID was initially set at 110 cm, with tube potential set
at a constant 75 kVp, with two outer chambers selected and a fine focal spot of 0.6 mm. SID was then
varied from 90 cm to 140 cm with two exposures made at each 5 cm interval, one using the AEC and
another with a constant 16 mAs derived from the initial exposure. Effective dose (E) and entrance surface
dose (ESD) were calculated for each acquisition. Seven experienced observers blindly graded image
quality using a 5-point Likert scale and 2 Alternative Forced Choice software. Signal-to-Noise Ratio (SNR)
was calculated for comparison. For each acquisition, femoral head diameter was also measured for
magnification indication.
Results: Results demonstrated that when increasing SID from 110 cm to 140 cm, both E and ESD reduced
by 3.7% and 17.3% respectively when using AEC and 50.13% and 41.79% respectively, when the constant
mAs was used. No significant statistical (T-test) difference (p ¼ 0.967) between image quality was
detected when increasing SID, with an intra-observer correlation of 0.77 (95% confidence level). SNR
reduced slightly for both AEC (38%) and no AEC (36%) with increasing SID.
Conclusion: For CR, increasing SID significantly reduces both E and ESD for AP pelvis imaging without
adversely affecting image quality
Wiggle-match radiocarbon dating of the Taupo eruption
The Taupo eruption deposit is an isochronous marker bed that spans much of New Zealand’s North Island and pre-dates human arrival. Holdaway et al. (2018, Nature Comms 9, 4110) propose that the current Taupo eruption date is inaccurate and that the eruption occurred “…decades to two centuries…” after the published wiggle-match estimate of 232 ± 10 CE (2 s.d.) derived from a tanekaha (Phyllocladus trichomanoides) tree at the Pureora buried forest site (Hogg et al. 2012, The Holocene 22, 439-449). Holdaway et al. (2018) propose that trees growing at Pureora (and other near-source areas) that were killed and buried by the climactic ignimbrite event were affected by ¹⁴C-depleted (magmatic) CO₂. Holdaway et al.'s (2018) proposal utilises a wide range of published ¹⁴C data, but their work results in assertions that are implausible. Four parts to their hypothesis are considered here
Effect of Lanadelumab Compared with Placebo on Prevention of Hereditary Angioedema Attacks : a Randomized Clinical Trial
Importance: Current treatments for long-term prophylaxis in hereditary angioedema have limitations. Objective: To assess the efficacy of lanadelumab, a fully human monoclonal antibody that selectively inhibits active plasma kallikrein, in preventing hereditary angioedema attacks. Design, Setting, and Participants: Phase 3, randomized, double-blind, parallel-group, placebo-controlled trial conducted at 41 sites in Canada, Europe, Jordan, and the United States. Patients were randomized between March 3, 2016, and September 9, 2016; last day of follow-up was April 13, 2017. Randomization was 2:1 lanadelumab to placebo; patients assigned to lanadelumab were further randomized 1:1:1 to 1 of the 3 dose regimens. Patients 12 years or older with hereditary angioedema type I or II underwent a 4-week run-in period and those with 1 or more hereditary angioedema attacks during run-in were randomized. Interventions: Twenty-six-week treatment with subcutaneous lanadelumab 150 mg every 4 weeks (n = 28), 300 mg every 4 weeks (n = 29), 300 mg every 2 weeks (n = 27), or placebo (n = 41). All patients received injections every 2 weeks, with those in the every-4-week group receiving placebo in between active treatments. Main Outcome and Measures: Primary efficacy end point was the number of investigator-confirmed attacks of hereditary angioedema over the treatment period. Results: Among 125 patients randomized (mean age, 40.7 years [SD, 14.7 years]; 88 females [70.4%]; 113 white [90.4%]), 113 (90.4%) completed the study. During the run-in period, the mean number of hereditary angioedema attacks per month in the placebo group was 4.0; for the lanadelumab groups, 3.2 for the every-4-week 150-mg group; 3.7 for the every-4-week 300-mg group; and 3.5 for the every-2-week 300-mg group. During the treatment period, the mean number of attacks per month for the placebo group was 1.97; for the lanadelumab groups, 0.48 for the every-4-week 150-mg group; 0.53 for the every-4-week 300-mg group; and 0.26 for the every-2-week 300-mg group. Compared with placebo, the mean differences in the attack rate per month were -1.49 (95% CI, -1.90 to -1.08; P <.001); -1.44 (95% CI, -1.84 to -1.04; P <.001); and -1.71 (95% CI, -2.09 to -1.33; P <.001). The most commonly occurring adverse events with greater frequency in the lanadelumab treatment groups were injection site reactions (34.1% placebo, 52.4% lanadelumab) and dizziness (0% placebo, 6.0% lanadelumab). Conclusions and Relevance: Among patients with hereditary angioedema type I or II, treatment with subcutaneous lanadelumab for 26 weeks significantly reduced the attack rate compared with placebo. These findings support the use of lanadelumab as a prophylactic therapy for hereditary angioedema. Further research is needed to determine long-term safety and efficacy. Trial Registration: EudraCT Identifier: 2015-003943-20; ClinicalTrials.gov Identifier: NCT02586805
Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector
A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results
Jet size dependence of single jet suppression in lead-lead collisions at sqrt(s(NN)) = 2.76 TeV with the ATLAS detector at the LHC
Measurements of inclusive jet suppression in heavy ion collisions at the LHC
provide direct sensitivity to the physics of jet quenching. In a sample of
lead-lead collisions at sqrt(s) = 2.76 TeV corresponding to an integrated
luminosity of approximately 7 inverse microbarns, ATLAS has measured jets with
a calorimeter over the pseudorapidity interval |eta| < 2.1 and over the
transverse momentum range 38 < pT < 210 GeV. Jets were reconstructed using the
anti-kt algorithm with values for the distance parameter that determines the
nominal jet radius of R = 0.2, 0.3, 0.4 and 0.5. The centrality dependence of
the jet yield is characterized by the jet "central-to-peripheral ratio," Rcp.
Jet production is found to be suppressed by approximately a factor of two in
the 10% most central collisions relative to peripheral collisions. Rcp varies
smoothly with centrality as characterized by the number of participating
nucleons. The observed suppression is only weakly dependent on jet radius and
transverse momentum. These results provide the first direct measurement of
inclusive jet suppression in heavy ion collisions and complement previous
measurements of dijet transverse energy imbalance at the LHC.Comment: 15 pages plus author list (30 pages total), 8 figures, 2 tables,
submitted to Physics Letters B. All figures including auxiliary figures are
available at
http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/HION-2011-02
- …