A Simple Quantum Computer

We propose an implementation of a quantum computer to solve Deutsch's problem, which requires exponential time on a classical computer but only linear time with quantum parallelism. By using a dual-rail qubit representation as a simple form of error correction, our machine can tolerate some amount of decoherence and still give the correct result with high probability. The design which we employ also demonstrates a signature for quantum parallelism which unambiguously delineates the desired quantum behavior from the merely classical. The experimental demonstration of our proposal using quantum optical components calls for the development of several key technologies common to single photonics.Comment: 8 pages RevTeX + 6 figures in postscrip

Boceprevir for untreated chronic HCV genotype 1 infection.

International audienceBACKGROUND: Peginterferon-ribavirin therapy is the current standard of care for chronic infection with hepatitis C virus (HCV). The rate of sustained virologic response has been below 50% in cases of HCV genotype 1 infection. Boceprevir, a potent oral HCV-protease inhibitor, has been evaluated as an additional treatment in phase 1 and phase 2 studies. METHODS: We conducted a double-blind study in which previously untreated adults with HCV genotype 1 infection were randomly assigned to one of three groups. In all three groups, peginterferon alfa-2b and ribavirin were administered for 4 weeks (the lead-in period). Subsequently, group 1 (the control group) received placebo plus peginterferon-ribavirin for 44 weeks; group 2 received boceprevir plus peginterferon-ribavirin for 24 weeks, and those with a detectable HCV RNA level between weeks 8 and 24 received placebo plus peginterferon-ribavirin for an additional 20 weeks; and group 3 received boceprevir plus peginterferon-ribavirin for 44 weeks. Nonblack patients and black patients were enrolled and analyzed separately. RESULTS: A total of 938 nonblack and 159 black patients were treated. In the nonblack cohort, a sustained virologic response was achieved in 125 of the 311 patients (40%) in group 1, in 211 of the 316 patients (67%) in group 2 (P<0.001), and in 213 of the 311 patients (68%) in group 3 (P<0.001). In the black cohort, a sustained virologic response was achieved in 12 of the 52 patients (23%) in group 1, in 22 of the 52 patients (42%) in group 2 (P=0.04), and in 29 of the 55 patients (53%) in group 3 (P=0.004). In group 2, a total of 44% of patients received peginterferon-ribavirin for 28 weeks. Anemia led to dose reductions in 13% of controls and 21% of boceprevir recipients, with discontinuations in 1% and 2%, respectively. CONCLUSIONS: The addition of boceprevir to standard therapy with peginterferon-ribavirin, as compared with standard therapy alone, significantly increased the rates of sustained virologic response in previously untreated adults with chronic HCV genotype 1 infection. The rates were similar with 24 weeks and 44 weeks of boceprevir

Comparison of embedded and added motor imagery training in patients after stroke: Study protocol of a randomised controlled pilot trial using a mixed methods approach

Copyright @ 2009 Schuster et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.Background: Two different approaches have been adopted when applying motor imagery (MI) to stroke patients. MI can be conducted either added to conventional physiotherapy or integrated within therapy sessions. The proposed study aims to compare the efficacy of embedded MI to an added MI intervention. Evidence from pilot studies reported in the literature suggests that both approaches can improve performance of a complex motor skill involving whole body movements, however, it remains to be demonstrated, which is the more effective one.Methods/Design: A single blinded, randomised controlled trial (RCT) with a pre-post intervention design will be carried out. The study design includes two experimental groups and a control group (CG). Both experimental groups (EG1, EG2) will receive physical practice of a clinical relevant motor task ('Going down, laying on the floor, and getting up again') over a two week intervention period: EG1 with embedded MI training, EG2 with MI training added after physiotherapy. The CG will receive standard physiotherapy intervention and an additional control intervention not related to MI.The primary study outcome is the time difference to perform the task from pre to post-intervention. Secondary outcomes include level of help needed, stages of motor task completion, degree of motor impairment, balance ability, fear of falling measure, motivation score, and motor imagery ability score. Four data collection points are proposed: twice during baseline phase, once following the intervention period, and once after a two week follow up. A nested qualitative part should add an important insight into patients' experience and attitudes towards MI. Semi-structured interviews of six to ten patients, who participate in the RCT, will be conducted to investigate patients' previous experience with MI and their expectations towards the MI intervention in the study. Patients will be interviewed prior and after the intervention period.Discussion: Results will determine whether embedded MI is superior to added MI. Findings of the semi-structured interviews will help to integrate patient's expectations of MI interventions in the design of research studies to improve practical applicability using MI as an adjunct therapy technique

The Nikumaroro bones identification controversy: First-hand examination versus evaluation by proxy — Amelia Earhart found or still missing?

YesAmerican celebrity aviator Amelia Earhart was lost over the Pacific Ocean during her press-making 1937 round-the-world flight. The iconic woman pilot remains a media interest nearly 80 years after her disappearance, with perennial claims of finds pinpointing her location. Though no sign of the celebrity pilot or her plane have been definitively identified, possible skeletal remains have been attributed to Earhart. The partial skeleton was recovered and investigated by British officials in 1940. Their investigation concluded that the remains were those of a stocky, middle-aged male. A private historic group re-evaluated the British analysis in 1998 as part of research to establish Gardner (Nikumaroro) Island as the crash site. The 1998 report discredited the British conclusions and used cranial analysis software (FORDISC) results to suggest that the skeleton was potentially a Northern European woman, and consistent with Amelia Earhart. A critical review of both investigations and contextual evidence shows that the original British osteological analyses were made by experienced, reliable professionals, while the cranial analysis is unreliable given the available data. Without access to the missing original bones, it is impossible to be definitive, but on balance, the most robust scientific analysis and conclusions are those of the original British finding indicating that the Nikumaroro bones belonged to a robust, middle-aged man, not Amelia Earhart

EBM in primary care: a qualitative multicenter study in Spain

<p>Abstract</p> <p>Background</p> <p>Evidence based medicine (EBM) has made a substantial impact on primary care in Spain over the last few years. However, little research has been done into family physicians (FPs)' attitudes related to EBM. The present study investigates FPs' perceptions of EBM in the primary care context.</p> <p>Methods</p> <p>This study used qualitative methodology. Information was obtained from 8 focus groups composed of 67 FPs from 47 health centers in 4 autonomous regions in Spain. Intentional sampling considered participants' previous education in EBM, and their experience as tutors in family medicine or working groups' members of the Spanish Society of Family Practice. Sociological discourse analysis was used with the support of the MAXqda software. Results were validated by means of triangulation among researchers and contrast with participants.</p> <p>Results</p> <p>Findings were grouped into three main areas: 1) The tug-of-war between the "science" of EBM and "experience" in the search for good clinical practice in primary care; 2) The development of EBM sensemaking as a reaction to contextual factors and interests; 3) The paradox of doubt and trust in the new EBM experts.</p> <p>The meaning of EBM was dynamically constructed within the primary care context. FPs did not consider good clinical practice was limited to the vision of science that EBM represents. Its use appeared to be conditioned by several factors that transcended the common concept of barriers. Along with concerns about its objectivity, participants showed a tendency to see EBM as the use of simplified guidelines developed by EBM experts.</p> <p>Conclusions</p> <p>The identification of science with EBM and its recognition as a useful but insufficient tool for the good clinical practice requires rethinking new meanings of evidence within the primary care reality. Beyond the barriers related to accessing and putting into practice the EBM, its reactive use can determine FPs' questions and EBM development in a direction not always centred on patients' needs. The questioning of experts' authority as a pillar of EBM could be challenged by the emergence of new kinds of EBM texts and experts to believe in.</p

Land/Homeland, Story/History: the social landscapes of the Southern Levant from Alexander to Augustus

This material has been published in revised form in The Social Archaeology of the Levant from Prehistory to the Present edited by Assaf Yasur-Landau, Eric H. Cline, and Yorke Rowan https://doi.org/10.1017/9781316661468.024. This version is free to view and download for private research and study only. Not for re-distribution or re-use. © Cambridge University PressThe Hellenistic era opens with Alexander the Great’s triumph over Achaemenid Persia, an event that inaugurates a millennium of western political hegemony over the Levant and paves the way for an infusion of western cultural ideas. I examine the social repercussions of this juncture of politics and culture for five self-identifying ethnoi within the region: Phoenicians (meaning Tyrians and Sidonians), Samaritans, Judeans, Idumeans, and Nabateans. I consider physical and written evidence as reflections of agency, opportunity, status, and authority, in order to reconstruct how people defined and presented themselves, and how they jockeyed for position and security in a crowded region and a volatile world. Fortunes fluctuated along with changes in imperial rule. The Ptolemies instituted a rapacious system of resource extraction, under which only the most nimble or removed kept their footing (i.e., Phoenicians, Nabateans). The Seleucids followed in the more magnanimous footsteps of the Achaemenids, offering a measure of economic and legal autonomy, an approach that placated some (e.g., Samaritans) and empowered others (e.g., Judeans). As Seleucid control weakened, groups used various means to claim status and authority. Samaritans, Judeans, and Idumeans deployed history and geography; Phoenicians and Nabateans depended on economic connections and cultural currency. Waning imperial powers in the later second century BCE left the region’s ethnoi effectively autonomous. Phoenicians and Nabateans became wealthy cosmopolitans connected to Mediterranean markets. Judeans unleashed an aggressive program of territorial acquisition, first successfully against Idumeans and Samaritans, then less so against Tyrians and Nabateans. Contemporary writers turned these events into historical narratives – divinely countenanced (1 Maccabees, Dead Sea Scrolls) vs. opportunistic circumstance (2 Maccabees, Tacitus, Josephus). These accounts offered people differing templates by which to situate themselves in place and history – templates ill-suited for co-existence. By the time Roman authorities established their imperial presence here in the mid-first century BCE, the social landscape was mined and ready to erupt.Accepted manuscrip

Optics and Quantum Electronics

Contains table of contents for Section 2 and reports on eleven research projects.Joint Services Electronics Program Contract DAAL03-89-C-0001National Science Foundation Grant EET 87-00474U.S. Air Force - Office of Scientific Research Contract F49620-88-C-0089Charles S. Draper Laboratory Contract DL-H-404179National Center for Integrated PhotonicsNational Science Foundation Grant ECS 87-18417NEC Research InstituteNational Science Foundation Grant ECS 85-52701Medical Free Electron Laser Program Contract N00014-86-K-0117National Institutes of Health Grant 5-RO1-GM35459Lawrence Livermore National Laboratory Contract B048704U.S. Department of Energy Grant DE-FG02-89-ER14012Columbia University Contract P016310