1,182 research outputs found
Seizure and the Risk for Seizure Recurrence Among Individuals Who Have Undergone Surgery for Epilepsy
Epilepsy is a central nervous system disorder for which recurrent seizures are the main symptom. Seizures resulting from epilepsy may culminate in unpredictable and sudden incapacitation, and thus are of significant concern to those interested in driver safety. Surgical therapy is one of the main treatment options for patients who do not respond to pharmacotherapy. Although approximately two thirds of individuals who undergo the most common types of surgery for epilepsy become seizure free, a significant proportion of these individuals will experience seizure recurrence. A systematic review and metaanalysis was conducted to examine the likelihood of seizure recurrence among individuals who have undergone surgery for epilepsy. Specifically, we were interested in quantifying the relationship between time since last seizure and the likelihood that a seizure will occur within the following year. Our results indicate that the longer the time that has elapsed since the occurrence of the last seizure, the lower the risk for seizure recurrence in the following year. The average annual risk for experiencing seizure recurrence among individuals who have remained seizure free for â„8 years is less than 2% and less than 1% for those who have remained seizure free for â„10 years. These findings have important implications for regulatory agencies with responsibility for road safety; particularly those agencies that regulate safety sensitive industries
Dose-finding study of ibrutinib and venetoclax in relapsed or refractory mantle cell lymphoma
Relapsed Mantle cell lymphoma (MCL) is often treated with Bruton\u27s tyrosine kinase inhibitors (BTKi); however, post-BTKi relapse can be challenging. Adding venetoclax (VEN) to ibrutinib (IBR) has shown synergy in preclinical MCL models. Prior MCL studies of the combination show promising efficacy but have conducted limited dose finding. We sought to identify the optimal dosing combination, based on efficacy and toxicity, utilizing a continual reassessment method of 6 combinations of IBR (280 mg, 420 mg, and 560 mg by mouth daily) and VEN (max dose of 200 mg and 400 mg by mouth daily). Eligible participants were not previously exposed to BTKi and not high risk for tumor lysis syndrome (TLS). VEN, initiated first at 100 mg, then at 20 mg by mouth daily after a TLS event, was started prior to adding IBR and ramped-up based on the dose level assigned. Combination treatment continued for six 28-day cycles. Thirty-five participants were enrolled and treated. One TLS event occurred with starting dose of 100 mg VEN; no TLS was seen with 20 mg. The optimal dosing combination was considered to be VEN 200 mg and IBR 420 mg with an overall response rate (ORR) of 93.8% (95% CI: 73.6% to 99.7%) and DLT incidence of 6.2% (95% CI: 0.3% to 26.4%). ORR for all arms was 82.3% (28/34; 95% CI: 65.5% to 93.2%) with a complete response (CR) rate of 42.4% (14/33; 95% CI: 25.5% to 60.8%). A participant was not allocated to IBR 560 mg and VEN 400 mg. ORR benefit was not seen with higher dosing combinations and toxicity was higher; a comparison made within the limitations of small cohorts. Resistance was seen in nearly all arms. This trial was registered at www.clinicaltrials.gov #NCT02419560
Air-Combat Strategy Using Approximate Dynamic Programming
Unmanned Aircraft Systems (UAS) have the potential to perform many
of the dangerous missions currently own by manned aircraft. Yet, the
complexity of some tasks, such as air combat, have precluded UAS from
successfully carrying out these missions autonomously. This paper presents
a formulation of a level flight, fixed velocity, one-on-one air combat maneuvering problem and an approximate dynamic programming (ADP) approach for computing an efficient approximation of the optimal policy. In the version of the problem formulation considered, the aircraft learning the
optimal policy is given a slight performance advantage. This ADP approach
provides a fast response to a rapidly changing tactical situation, long planning horizons, and good performance without explicit coding of air combat tactics. The method's success is due to extensive feature development, reward shaping and trajectory sampling. An accompanying fast and e ffective rollout-based policy extraction method is used to accomplish on-line implementation. Simulation results are provided that demonstrate the robustness of the method against an opponent beginning from both off ensive and defensive situations. Flight results are also presented using micro-UAS own at MIT's Real-time indoor Autonomous Vehicle test ENvironment
(RAVEN).Defense University Research Instrumentation Program (U.S.) (grant number FA9550-07-1-0321)United States. Air Force Office of Scientific Research (AFOSR # FA9550-08-1-0086)American Society for Engineering Education (National Defense Science and Engineering Graduate Fellowship
A global plate model including lithospheric deformation along major rifts and orogens since the Triassic
Global deepâtime plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global MesozoicâCenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 Ă 10^6 km^2 in the Late Jurassic (~160â155 Ma), driven by a vast network of rift systems. After a midâCretaceous drop in deformation, it reaches a high of 48 x 10^6 km^2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plateâmantle system
A global plate model including lithospheric deformation along major rifts and orogens since the Triassic
Global deepâtime plate motion models have traditionally followed a classical rigid plate approach, even though plate deformation is known to be significant. Here we present a global MesozoicâCenozoic deforming plate motion model that captures the progressive extension of all continental margins since the initiation of rifting within Pangea at ~240 Ma. The model also includes major failed continental rifts and compressional deformation along collision zones. The outlines and timing of regional deformation episodes are reconstructed from a wealth of published regional tectonic models and associated geological and geophysical data. We reconstruct absolute plate motions in a mantle reference frame with a joint global inversion using hot spot tracks for the last 80 million years and minimizing global trench migration velocities and net lithospheric rotation. In our optimized model, net rotation is consistently below 0.2°/Myr, and trench migration scatter is substantially reduced. Distributed plate deformation reaches a Mesozoic peak of 30 Ă 10^6 km^2 in the Late Jurassic (~160â155 Ma), driven by a vast network of rift systems. After a midâCretaceous drop in deformation, it reaches a high of 48 x 10^6 km^2 in the Late Eocene (~35 Ma), driven by the progressive growth of plate collisions and the formation of new rift systems. About a third of the continental crustal area has been deformed since 240 Ma, partitioned roughly into 65% extension and 35% compression. This community plate model provides a framework for building detailed regional deforming plate networks and form a constraint for models of basin evolution and the plateâmantle system
The Australasian Resuscitation In Sepsis Evaluation: FLUid or vasopressors In Emergency Department Sepsis, a multicentre observational study (ARISE FLUIDS observational study): Rationale, methods and analysis plan
There is uncertainty about the optimal i.v. fluid volume and timing of vasopressor commencement in the resuscitation of patients with sepsis and hypotension. We aim to study current resuscitation practices in EDs in Australia and New Zealand (the Australasian Resuscitation In Sepsis Evaluation: FLUid or vasopressors In Emergency Department Sepsis [ARISE FLUIDS] observational study).ARISE FLUIDS is a prospective, multicentre observational study in 71 hospitals in Australia and New Zealand. It will include adult patients presenting to the ED during a 30 day period with suspected sepsis and hypotension (systolic blood pressur
Ex vivo 18F-fluoride uptake and hydroxyapatite deposition in human coronary atherosclerosis
Early microcalcification is a feature of coronary plaques with an increased propensity to rupture and to cause acute coronary syndromes. In this ex vivo imaging study of coronary artery specimens, the non-invasive imaging radiotracer, 18F-fluoride, was highly selective for hydroxyapatite deposition in atherosclerotic coronary plaque. Specifically, coronary 18F-fluoride uptake had a high signal to noise ratio compared with surrounding myocardium that makes it feasible to identify coronary mineralisation activity. Areas of 18F-fluoride uptake are associated with osteopontin, an inflammation-associated glycophosphoprotein that mediates tissue mineralisation, and Runt-related transcription factor 2, a nuclear protein involved in osteoblastic differentiation. These results suggest that 18F-fluoride is a non-invasive imaging biomarker of active coronary atherosclerotic mineralisation
US Cosmic Visions: New Ideas in Dark Matter 2017: Community Report
This white paper summarizes the workshop "U.S. Cosmic Visions: New Ideas in
Dark Matter" held at University of Maryland on March 23-25, 2017.Comment: 102 pages + reference
From chloroquine to artemether-lumefantrine: the process of drug policy change in Zambia
<p>Abstract</p> <p>Background</p> <p>Following the recognition that morbidity and mortality due to malaria had dramatically increased in the last three decades, in 2002 the government of Zambia reviewed its efforts to prevent and treat malaria. Convincing evidence of the failing efficacy of chloroquine resulted in the initiation of a process that eventually led to the development and implementation of a new national drug policy based on artemisinin-based combination therapy (ACT).</p> <p>Methods</p> <p>All published and unpublished documented evidence dealing with the antimalarial drug policy change was reviewed. These data were supplemented by the authors' observations of the policy change process. The information has been structured to capture the timing of events, the challenges encountered, and the resolutions reached in order to achieve implementation of the new treatment policy.</p> <p>Results</p> <p>A decision was made to change national drug policy to artemether-lumefantrine (AL) in the first quarter of 2002, with a formal announcement made in October 2002. During this period, efforts were undertaken to identify funding for the procurement of AL and to develop new malaria treatment guidelines, training materials, and plans for implementation of the policy. In order to avoid a delay in implementation, the policy change decision required a formal adoption within existing legislation. Starting with donated drug, a phased deployment of AL began in January 2003 with initial use in seven districts followed by scaling up to 28 districts in the second half of 2003 and then to all 72 districts countrywide in early 2004.</p> <p>Conclusion</p> <p>Drug policy changes are not without difficulties and demand a sustained international financing strategy for them to succeed. The Zambian experience demonstrates the need for a harmonized national consensus among many stakeholders and a political commitment to ensure that new policies are translated into practice quickly. To guarantee effective policies requires more effort and recognition that this becomes a health system and not a drug issue. This case study attempts to document the successful experience of change to ACT in Zambia and provides a realistic overview of some of the painful experiences and important lessons learnt.</p
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