In this paper we examine the effect that different knowledge sharing strategies have on the performance of our parallel QBF Solver PaQuBE. This new Master/Slave MPI based solver leverages the ...additional computational power that can be exploited from modern computer and system architectures, to solve more relevant instances and faster than previous generation solvers. Knowledge sharing plays a critical role in the performance of PaQuBE. However, due to the overhead associated with sending and receiving MPI messages, and the restricted communication/network bandwidth available between solvers, it is essential that we optimize not only which information is shared, but how it is shared. In this context, we compare multiple conflict clause and solution cube sharing strategies, and finally show that an adaptive method works best. Additionally, compression of solution cubes was explored which reduced the system time associated with message passing while also reducing network traffic.
Over a 2-yr period (1984-1985) we performed emergent endoscopic injection sclerotherapy (EIS) within 12 h in 25 consecutive episodes of variceal hemorrhage (VH). The outcome was compared to the ...preemergent period (1982-1984) when 22 episodes of VH were treated first with vasopressin and balloon tamponade, and then by EIS, in cases which failed to resolve. In those with decompensated liver disease, average transfusions dropped from 12.3 to 7.1 units of blood. Continued bleeding decreased from 53% to 13% and mortality from 47% to 13%. Persons with compensated liver disease had fewer recurrent bleeding episodes, and tended toward decreased transfusion requirements and mortality with EIS. Our experience suggests that emergent EIS is the treatment of choice for acute VH.
Leadership implies power. We argue, from a social embodiment perspective, that thinking about power involves mental simulations of vertical location. Three studies tested whether judgments of ...leaders' power and information on a vertical location are interrelated. In Studies 1a-c, participants judged a leader's power after being presented with, among other information, an organization chart containing either a long or a short vertical line. A longer vertical line increased judged power. Study 2 showed that this effect persists when longer (vs. shorter) vertical lines are presented in an independent priming task and not in an organization chart, and that horizontal lines do not have the same effect. Finally, Studies 3a and 3b showed the reverse causal effect: Information about a leader's power influenced participants' vertical positioning of a leader's box in an organization chart and of a leader picture into a team picture. Implications for leadership communication are discussed.
Nanostructured carbon powders are prepared from graphite powder in a planetary mill using WC, stainless steel, and agate milling tools. The evolution of microstructure and chemical reactivity is ...studied by X-ray diffraction and combustion methods, respectively. The specific surface area of milled samples is determined by BET measurement and the impurity content is estimated by spark source mass spectroscopy. There is no monotonous relationship between reactivity and specific surface area of particles and agglomerations of particles. In contrast to impurity contents, distortion of atomic short- and medium-range order is shown to be essential for the observed enhancement of chemical reactivity. A statistical model for the milling process is formulated and used to discuss the experimental data. As a result, an expression for the dependence of combustion temperature on milling time is proposed.
To determine the efficacy of misoprostol for the prevention of nonsteroidal anti-inflammatory drug (NSAID)-induced duodenal and gastric ulcers in arthritis patients receiving NSAID therapy.
A ...randomized, double-blind, multicenter, placebo-controlled trial.
Six hundred thirty-eight private, Veterans Affairs, health maintenance, and academic practices.
Six hundred thirty-eight patients with chronic inflammatory or noninflammatory arthritis who were taking an NSAID but who did not have a gastric or duodenal ulcer on screening endoscopy received treatment with ibuprofen, piroxicam, naproxen, sulindac, tolmetin, indomethacin, or diclofenac daily for 3 months. Four hundred fifty-five (71%) patients completed the trial.
Patients meeting the entry criteria were randomized to receive either misoprostol, 200 micrograms, or placebo, four times a day for 12 weeks.
The endoscopy was repeated at 4, 8, and 12 weeks. The development of a duodenal or gastric ulcer (defined as a circumscribed mucosal defect > or = 0.5 cm in diameter and with perceptible depth) was regarded as prophylactic failure.
By 12 weeks, a duodenal ulcer developed in 2 of 320 (0.6%; 95% CI, 0.2% to 3.9%) patients randomized to receive misoprostol, compared with 15 of 323 (4.6%; CI, 2.8% to 8%) patients receiving placebo (P = 0.002). A gastric ulcer developed in 6 of 320 (1.9%; (CI, 0.8% to 4.4%) patients, compared with in 25 of 323 (7.7%; CI, 5.1% to 11.4%), respectively.
Misoprostol significantly lowers the frequency of both duodenal and gastric ulcer development in patients who require long-term therapy with NSAIDS.
Thin films alloys of Pd and Ni make good sensors for H partial pressures (p H sub 2 ) over a very wide range: from 10 exp )3 to 700 Torr. For pH sub 2 from 1-700 Torr the atomic percent of Ni in the ...alloy has a strong effect on the change in film resistance which is used as the sensing property. The phase transition from the alpha - to the hydride beta -phase must be avoided to maintain a reversible sensor. The characteristics of alloys with Ni of 3, 5.3, 8 and 15% are reported. The phase transition was found in the 5.3% alloy at approx25o Torr, but alloys of Ni > 8% showed no phase change behaviour up to 630 Torr (pure H sub 2 ) at ambient temperatures. Other characteristics of the Pd/Ni alloy sensors are also reported, including the effect of temperature, oxygen, and relative humidity, and the speed of response to step changes in p H sub 2 .
A two-phase study was conducted on the relationship between organizational climate variables and burnout among personnel in a multifunction community service agency. Initial interviews with a small ...pilot sample identified major sources of stress, which were then incorporated into a second-phase questionnaire to all staff. Multiple regression analyses illustrated that perceived interactions between head office administrators and sections of the agency contributed significantly to emotional exhaustion, whereas perceptions of within-section interactions and involvement in decision-making had a positive impact on personal accomplishment. Perceived communication levels, however, were negatively related to personal accomplishment. The findings suggest the importance of organizational variables and highlight strategies for burnout reduction and effective stress management in human service organizations.
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