1,394 research outputs found
Corn Silage Variety Trial Archive
This report features the available corn silage data from 2003-2017. Crop performance testing results are released annually through the activities of SDSU Extension and the South Dakota Agricultural Experiment Station at SDSU
Formation of Black Holes from Collapsed Cosmic String Loops
The fraction of cosmic string loops which collapse to form black holes is
estimated using a set of realistic loops generated by loop fragmentation. The
smallest radius sphere into which each cosmic string loop may fit is obtained
by monitoring the loop through one period of oscillation. For a loop with
invariant length which contracts to within a sphere of radius , the
minimum mass-per-unit length necessary for the cosmic string
loop to form a black hole according to the hoop conjecture is . Analyzing loops, we obtain the empirical estimate for the fraction of cosmic string
loops which collapse to form black holes as a function of the mass-per-unit
length in the range . We
use this power law to extrapolate to , obtaining the
fraction of physically interesting cosmic string loops which
collapse to form black holes within one oscillation period of formation.
Comparing this fraction with the observational bounds on a population of
evaporating black holes, we obtain the limit on the cosmic string mass-per-unit-length. This limit is consistent
with all other observational bounds.Comment: uuencoded, compressed postscript; 20 pages including 7 figure
Periprosthetic joint infection: are patients with multiple prosthetic joints at risk?
Patients who present with a periprosthetic joint infection in a single joint may have multiple prosthetic joints. The risk of these patients developing a subsequent infection in another prosthetic joint is unknown. Our purposes were (1) to identify the risk of developing a subsequent infection in another prosthetic joint and (2) to describe the time span and organism profile to the second prosthetic infection. We retrospectively identified 55 patients with periprosthetic joint infection who had another prosthetic joint in place at the time of presentation. Of the 55 patients, 11 (20%) developed a periprosthetic joint infection in a second joint. The type of organism was the same as the first infection in 4 (36%) of 11 patients. The time to developing a second infection averaged 2.0 years (range, 0-6.9 years)
A prospective analysis of glove perforation in primary and revision total hip and total knee arthroplasty.
Literature in regard to glove perforation rates in revision total joint arthroplasty (TJA) is scarce. Our purpose was to determine the incidence of perforation in revision TJA. Gloves from all scrubbed personnel were tested based on the American Society for Testing and Materials. A total of 3863 gloves were collected from 58 primary and 36 revision arthroplasty cases. Surgeons had a 3.7% outer-glove perforation rate in primary TJA compared with 8.9% in revision TJA. When both gloves were perforated, the outer-glove perforation was recognized intraoperatively 100% of the time, and the inner-glove perforation was noted only 19% of the time. The surgeon has the highest rate of glove perforation. Outer-glove perforations should prompt careful inspection of the inner glove
Periprosthetic joint infection increases the risk of one-year mortality.
BACKGROUND: Periprosthetic joint infection continues to potentially complicate an otherwise successful joint replacement. The treatment of this infection often requires multiple surgical procedures associated with increased complications and morbidity. This study examined the relationship between periprosthetic joint infection and mortality and aimed to determine the effect of periprosthetic joint infection on mortality and any predictors of mortality in patients with periprosthetic joint infection.
METHODS: Four hundred and thirty-six patients with at least one surgical intervention secondary to confirmed periprosthetic joint infection were compared with 2342 patients undergoing revision arthroplasty for aseptic failure. The incidence of mortality at thirty days, ninety days, one year, two years, and five years after surgery was assessed. Multivariate analysis was used to assess periprosthetic joint infection as an independent predictor of mortality. In the periprosthetic joint infection population, variables investigated as potential risk factors for mortality were evaluated.
RESULTS: Mortality was significantly greater (p \u3c 0.001) in patients with periprosthetic joint infection compared with those undergoing aseptic revision arthroplasty at ninety days (3.7% versus 0.8%), one year (10.6% versus 2.0%), two years (13.6% versus 3.9%), and five years (25.9% versus 12.9%). After controlling for age, sex, ethnicity, number of procedures, involved joint, body mass index, and Charlson Comorbidity Index, revision arthroplasty for periprosthetic joint infection was associated with a fivefold increase in mortality compared with revision arthroplasty for aseptic failures. In the periprosthetic joint infection population, independent predictors of mortality included increasing age, higher Charlson Comorbidity Index, history of stroke, polymicrobial infections, and cardiac disease.
CONCLUSIONS: Although it is well known that periprosthetic joint infection is a devastating complication that severely limits joint function and is consistently difficult to eradicate, surgeons must also be cognizant of the systemic impact of periprosthetic joint infection and its major influence on fatal outcome in patients
Superbeam Studies at CERN
A conventional low energy neutrino beam of great intensity could be produced by the Super Proton Linac at CERN as a first stage of a Neutrino Factory. Water Cerenkov and liquid scintillator detectors are studied as possible candidates for a neutrino oscillation experiment which could improve ourcurrent knowledge of the atmospheric parameters deltam2atm , delta23 and measure or severely constrain 13. It is also shown that a very large water detector could eventually observe leptonic CP violation
Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems
Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition
How the perceived neighbourhood environment influences active living in older dwellers of an Asian ultra-dense metropolis
The way older adults perceive their neighbourhood environment may determine their levels of physical activity. We examined the associations of perceived neighbourhood environmental attributes with accelerometry-assessed and self-reported physical activity and sedentary time in Hong Kong Chinese older adults. In doing so, we estimated the inter-relationships among perceived environmental attributes, the mediating role of physical activity in the environment-sedentary time nexus and the moderating role of sex. We used data from the Active Lifestyle and the Environment in Chinese Seniors (ALECS) project collected on older adults (N = 909; ≥65 years) living in neighbourhoods varying in walkability and socio-economic status (71 % response rate). Self-reported physical activity and perceived neighbourhood attributes were assessed with validated questionnaires. Accelerometer-based physical activity and sedentary time were collected in 402 participants. Older adults who perceived their neighbourhood to be walkable, safe, aesthetically pleasing and equipped with public sitting facilities engaged in more physical activity and less sedentary time. Curvilinear relations of perceived residential density and activity-friendly urban design features indicated that extreme levels of density may not be optimal for older adults to adopt an active lifestyle because they do not provide sufficient space for sitting facilities and greenery and do not result in better perceptions of neighbourhood walkability when compared to areas with moderate-to-high levels of density. Creative solutions for the incorporation of greenery and public places for sitting in megacities are needed
Enhanced TCR-induced Apoptosis in Interferon Regulatory Factor 4–deficient CD4+ Th Cells
Transcription factors of the interferon regulatory factor (IRF) family contribute to the regulation of cell proliferation and apoptosis. Here, we show that CD4+ T helper (Th) cells lacking IRF4 (IRF4−/−) are highly sensitive to apoptosis. After infection of IRF4−/− mice with the protozoan parasite Leishmania major, the lesion-draining lymph nodes developed the prototypic lymphadenopathy of wild-type mice after 4 wk, but demonstrated almost total loss of cellularity and enhanced apoptosis after 7 wk. In vitro, activation of IRF4−/− CD4+ Th cells led to greatly increased apoptosis compared with wild-type cells. Coculture of IRF4−/− and IRF4+/+ CD4+ cells did not increase survival of IRF4−/− CD4+ cells, indicating that the enhanced rate of IRF4−/− Th cell apoptosis was neither transferable nor due to lack of a cytokine. Enhanced CD4+ cell apoptosis was also observed after anti-CD95 mAb treatment, despite normal CD95 expression. Removal of endogenous cytokines, notably interleukin (IL)-4, led to increased and equally high levels of IRF4−/− and IRF4+/+ cell apoptosis, whereas the protective activity of exogenous IL-4 was reduced in IRF4−/− CD4+ cells despite normal expression of the IL-4 receptor. Therefore, IRF4 is central in protecting CD4+ cells against proapoptotic stimuli
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