1,323 research outputs found

    Transcranial magnetic stimulation for the treatment of epilepsy

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    © 2016 The Cochrane Collaboration.Background: Epilepsy is a highly prevalent neurological condition characterized by repeated unprovoked seizures with various etiologies. Although antiepileptic medications produce clinical improvement in most individuals, nearly a third of individuals have drug-resistant epilepsy that carries significant morbidity and mortality. There remains a need for non-invasive and more effective therapies for this population. Transcranial magnetic stimulation (TMS) uses electromagnetic coils to excite or inhibit neurons, with repetitive pulses at low-frequency producing an inhibitory effect that could conceivably reduce cortical excitability associated with epilepsy. Objectives: To assess the evidence for the use of TMS in individuals with drug-resistant epilepsy compared with other available treatments in reducing seizure frequency, improving quality of life, reducing epileptiform discharges, antiepileptic medication use, and side-effects. Search methods: We searched the Cochrane Epilepsy Group Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) via the Cochrane Register of Studies Online (CRSO), MEDLINE (Ovid 1946 to 10 March 2016), ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (ICTRP) up to March 2016. We also searched SCOPUS (1823 to June 2014) as a substitute for Embase (but it is no longer necessary to search SCOPUS, because randomized controlled trials (RCTs) and quasi-RCTs in EMBASE are now included in CENTRAL). Selection criteria: Eligible studies were RCTs that were double-blinded, single-blinded or unblinded, and placebo, no treatment, or active controlled, which used repetitive transcranial magnetic stimulation (rTMS) without restriction of frequency, duration, intensity, or setup (focal or vertex treatment) on patients with drug-resistant epilepsy. The search revealed 274 records from the databases, that after selection provided seven full-text relevant studies for inclusion. Of the seven studies included, five were completed studies with published data and included randomized, blinded trials. The total number of participants in the seven trials was 230. Data collection and analysis: We extracted information from each trial including methodological data; participant demographics including baseline seizure frequency, type of epileptic drugs taken; intervention details and intervention groups for comparison; potential biases; and outcomes and time points, primarily change in seizure frequency or responder rates, as well as quality of life and epileptiform discharges, adverse effects, and changes in medication use. Main results: Two of the seven studies analyzed showed a statistically significant reduction in seizure rate from baseline (72% and 78.9% reduction of seizures per week from the baseline rate, respectively). The other five studies showed no statistically significant difference in seizure frequency following rTMS treatment compared with controls. We were not able to combine the results of the trials in analysis due to differences in the designs of the studies. Four studies evaluated our secondary endpoint of mean number of epileptic discharges, and three of the four showed a statistically significant reduction in discharges. Quality of life was not assessed in any of the studies. Adverse effects were uncommon among the studies and typically involved headache, dizziness, and tinnitus. No significant changes in medication use were found in the trials. Authors' conclusions: Overall, we judged the quality of evidence for the primary outcomes of this review to be low. There is evidence that rTMS is safe and not associated with any adverse events, but given the variability in technique and outcome reporting that prevented meta-analysis, the evidence for efficacy of rTMS for seizure reduction is still lacking despite reasonable evidence that it is effective at reducing epileptiform discharges

    Managing the complexity of doing it all : an exploratory study on students' experiences when trained stepwise in conducting consultations

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    Background: At most medical schools the components required to conduct a consultation, medical knowledge, communication, clinical reasoning and physical examination skills, are trained separately. Afterwards, all the knowledge and skills students acquired must be integrated into complete consultations, an art that lies at the heart of the medical profession. Inevitably, students experience conducting consultations as complex and challenging. Literature emphasizes the importance of three didactic course principles: moving from partial tasks to whole task learning, diminishing supervisors' support and gradually increasing students' responsibility. This study explores students' experiences of an integrated consultation course using these three didactic principles to support them in this difficult task. Methods: Six focus groups were conducted with 20 pre-clerkship and 19 clerkship students in total. Discussions were audiotaped, transcribed and analysed by Nvivo using the constant comparative strategy within a thematic analysis. Results: Conducting complete consultations motivated students in their learning process as future physician. Initially, students were very much focused on medical problem solving. Completing the whole task of a consultation obligated them to transfer their theoretical medical knowledge into applicable clinical knowledge on the spot. Furthermore, diminishing the support of a supervisor triggered students to reflect on their own actions but contrasted with their increased appreciation of critical feedback. Increasing students' responsibility stimulated their active learning but made some students feel overloaded. These students were anxious to miss patient information or not being able to take the right decisions or to answer patients' questions, which sometimes resulted in evasive coping techniques, such as talking faster to prevent the patient asking questions. Conclusion: The complex task of conducting complete consultations should be implemented early within medical curricula because students need time to organize their medical knowledge into applicable clinical knowledge. An integrated consultation course should comprise a step-by-step teaching strategy with a variety of supervisors' feedback modi, adapted to students' competence. Finally, students should be guided in formulating achievable standards to prevent them from feeling overloaded in practicing complete consultations with simulated or real patients

    Sex differences in mathematics and reading achievement are inversely related: within- and across-nation assessment of 10 years of PISA data

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    We analyzed one decade of data collected by the Programme for International Student Assessment (PISA), including the mathematics and reading performance of nearly 1.5 million 15 year olds in 75 countries. Across nations, boys scored higher than girls in mathematics, but lower than girls in reading. The sex difference in reading was three times as large as in mathematics. There was considerable variation in the extent of the sex differences between nations. There are countries without a sex difference in mathematics performance, and in some countries girls scored higher than boys. Boys scored lower in reading in all nations in all four PISA assessments (2000, 2003, 2006, 2009). Contrary to several previous studies, we found no evidence that the sex differences were related to nations’ gender equality indicators. Further, paradoxically, sex differences in mathematics were consistently and strongly inversely correlated with sex differences in reading: Countries with a smaller sex difference in mathematics had a larger sex difference in reading and vice versa. We demonstrate that this was not merely a between-nation, but also a within-nation effect. This effect is related to relative changes in these sex differences across the performance continuum: We did not find a sex difference in mathematics among the lowest performing students, but this is where the sex difference in reading was largest. In contrast, the sex difference in mathematics was largest among the higher performing students, and this is where the sex difference in reading was smallest. The implication is that if policy makers decide that changes in these sex differences are desired, different approaches will be needed to achieve this for reading and mathematics. Interventions that focus on high-achieving girls in mathematics and on low achieving boys in reading are likely to yield the strongest educational benefits

    ‘It used to be brutal, now it’s an art’:changing negotiations of violence and masculinity in British karate

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    In most western (and indeed eastern) cultures, fighting is seen as an ultimate symbol of masculinity – an embodied display of dominance, control and violence (Bourdieu, 2001). As a space legitimising and praising performances of mimetic violence (Dunning, 1999), combat sports provide an arena where the virtues of dominance and power at the heart of conceptions of orthodox masculinity (Anderson, 2010 ) or hegemonic masculinity (Connell, 2005) can be symbolically presented by men through bodily displays of strength, physical aggression, and the taking and overcoming of pain (Bourdieu, 2001; Messner, 1990; Wacquant, 2004). Yet, over the last twenty years the focus of karate in Britain has been perceived to shift from aggressive acts of 'hitting hard' to developing and displaying controlled, acrobatic and technically precise movements. Drawn from a nine-month ethnography and 7 semi-structured interviews, this chapter explores how British male karate practitioners re/negotiate ideas of masculinity and embodiments of a masculine identity in the context of karate’s changing emphasis on, and practices of, 'violence'. This paper suggests that a 'civilising' shift (Elias and Dunning, 1986) in the competition rules increases in women’s participation in karate with men, and subsequent negotiations of mimetic violence, complicate the use of violence as a symbol of praised masculine identity within British karate . A praised masculine identity is crafted by carefully blending traits conventional deemed feminine such as technical precision, elegance and agility alongside displays of strength and dominance. Such performances challenge conceptions of an orthodox sporting masculinity and notions of hierarchical gender distinction

    Mitochondrial DNA Polymorphism A4917G Is Independently Associated with Age-Related Macular Degeneration

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    The objective of this study was to determine if MTND2*LHON4917G (4917G), a specific non-synonymous polymorphism in the mitochondrial genome previously associated with neurodegenerative phenotypes, is associated with increased risk for age-related macular degeneration (AMD). A preliminary study of 393 individuals (293 cases and 100 controls) ascertained at Vanderbilt revealed an increased occurrence of 4917G in cases compared to controls (15.4% vs.9.0%, p = 0.11). Since there was a significant age difference between cases and controls in this initial analysis, we extended the study by selecting Caucasian pairs matched at the exact age at examination. From the 1547 individuals in the Vanderbilt/Duke AMD population association study (including 157 in the preliminary study), we were able to match 560 (280 cases and 280 unaffected) on exact age at examination. This study population was genotyped for 4917G plus specific AMD-associated nuclear genome polymorphisms in CFH, LOC387715 and ApoE. Following adjustment for the listed nuclear genome polymorphisms, 4917G independently predicts the presence of AMD (OR = 2.16, 95%CI 1.20–3.91, p = 0.01). In conclusion, a specific mitochondrial polymorphism previously implicated in other neurodegenerative phenotypes (4917G) appears to convey risk for AMD independent of recently discovered nuclear DNA polymorphisms

    An Integrated-Photonics Optical-Frequency Synthesizer

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    Integrated-photonics microchips now enable a range of advanced functionalities for high-coherence applications such as data transmission, highly optimized physical sensors, and harnessing quantum states, but with cost, efficiency, and portability much beyond tabletop experiments. Through high-volume semiconductor processing built around advanced materials there exists an opportunity for integrated devices to impact applications cutting across disciplines of basic science and technology. Here we show how to synthesize the absolute frequency of a lightwave signal, using integrated photonics to implement lasers, system interconnects, and nonlinear frequency comb generation. The laser frequency output of our synthesizer is programmed by a microwave clock across 4 THz near 1550 nm with 1 Hz resolution and traceability to the SI second. This is accomplished with a heterogeneously integrated III/V-Si tunable laser, which is guided by dual dissipative-Kerr-soliton frequency combs fabricated on silicon chips. Through out-of-loop measurements of the phase-coherent, microwave-to-optical link, we verify that the fractional-frequency instability of the integrated photonics synthesizer matches the 7.010137.0*10^{-13} reference-clock instability for a 1 second acquisition, and constrain any synthesis error to 7.710157.7*10^{-15} while stepping the synthesizer across the telecommunication C band. Any application of an optical frequency source would be enabled by the precision optical synthesis presented here. Building on the ubiquitous capability in the microwave domain, our results demonstrate a first path to synthesis with integrated photonics, leveraging low-cost, low-power, and compact features that will be critical for its widespread use.Comment: 10 pages, 6 figure

    Valorizing the Human Capital Within Organizations : A Competency Based Approach

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    Changes in the business environment and in the nature of work itself require the implementation of integrated and flexible methodologies in competencies’ definition in order to valorize the human capital and achieve organizational targets in a future-oriented perspective. However, extant research suggests that the available approaches to competency definition are more focused on describing past behaviors than on anticipating future requirements. Therefore, this study endeavors to provide a competency-based model that supports the top management in the identification of the competencies employees should posses, highlighting crucial competencies that can translate the strategy and vision of the organization into behaviors, skills, and terms that people can easily understand and implement. The results of our explorative case study led us to identify a set of competencies (digital/analytical/technical/adaptive/combinative/proactive), classified following the Knowledge Skills Attitudes (KSA) model, that collectively lead to a successful definition of future-oriented competencies.© 2019 Springer. This is a post-peer-review, pre-copyedit version of an article published in Advances in Human Factors, Business Management and Society. AHFE 2018. The final authenticated version is available online at: https://doi.org/10.1007/978-3-319-94709-9_6fi=vertaisarvioitu|en=peerReviewed

    Modest induction of phase 2 enzyme activity in the F-344 rat prostate

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    BACKGROUND: Prostate cancer is the most commonly diagnosed malignancy in men and is thought to arise as a result of endogenous oxidative stress in the face of compromised carcinogen defenses. We tested whether carcinogen defense (phase 2) enzymes could be induced in the prostate tissues of rats after oral feeding of candidate phase 2 enzyme inducing compounds. METHODS: Male F344 rats were gavage fed sulforaphane, β-naphthoflavone, curcumin, dimethyl fumarate or vehicle control over five days, and on the sixth day, prostate, liver, kidney and bladder tissues were harvested. Cytosolic enzyme activities of nicotinamide quinone oxidoreductase (NQO1), total glutathione transferase (using DCNB) and mu-class glutathione transferase (using CDNB) were determined in the treated and control animals and compared. RESULTS: In prostatic tissues, sulforaphane produced modest but significant increases in the enzymatic activities of NQO1, total GST and GST-mu compared to control animals. β-naphthoflavone significantly increased NQO1 and GST-mu activities and curcumin increased total GST and GST-mu enzymatic activities. Dimethyl fumarate did not significantly increase prostatic phase 2 enzyme activity. Compared to control animals, sulforaphane also significantly induced NQO1 or total GST enzyme activity in the liver, kidney and, most significantly, in the bladder tissues. All compounds were well tolerated over the course of the gavage feedings. CONCLUSION: Orally administered compounds will induce modestly phase 2 enzyme activity in the prostate although the significance of this degree of induction is unknown. The 4 different compounds also altered phase 2 enzyme activity to different degrees in different tissue types. Orally administered sulforaphane potently induces phase 2 enzymes in bladder tissues and should be investigated as a bladder cancer preventive agent

    Direct measurement of local oxygen concentration in the bone marrow of live animals

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    Characterizing how the microenvironment, or niche, regulates stem cell activity is central to understanding stem cell biology and to developing strategies for therapeutic manipulation of stem cells1. Low oxygen tension (hypoxia) is commonly thought to be a shared niche characteristic in maintaining quiescence in multiple stem cell types2–4. However, support for the existence of a hypoxic niche has largely come from indirect evidence such as proteomic analysis5, expression of HIF-1 and related genes6, and staining with surrogate hypoxic markers (e.g. pimonidazole)6–8. Here we perform direct in vivo measurements of local oxygen tension (pO2) in the bone marrow (BM) of live mice. Using two-photon phosphorescence lifetime microscopy (2PLM), we determined the absolute pO2 of the BM to be quite low (<32 mmHg) despite very high vascular density. We further uncovered heterogeneities in local pO2, with the lowest pO2 (~9.9 mmHg, or 1.3%) found in deeper peri-sinusoidal regions. The endosteal region, by contrast, is less hypoxic as it is perfused with small arteries that are often positive for the marker nestin. These pO2 values change dramatically after radiation and chemotherapy, pointing to the role of stress in altering the stem cell metabolic microenvironment
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