Matroids and Quantum Secret Sharing Schemes

A secret sharing scheme is a cryptographic protocol to distribute a secret state in an encoded form among a group of players such that only authorized subsets of the players can reconstruct the secret. Classically, efficient secret sharing schemes have been shown to be induced by matroids. Furthermore, access structures of such schemes can be characterized by an excluded minor relation. No such relations are known for quantum secret sharing schemes. In this paper we take the first steps toward a matroidal characterization of quantum secret sharing schemes. In addition to providing a new perspective on quantum secret sharing schemes, this characterization has important benefits. While previous work has shown how to construct quantum secret sharing schemes for general access structures, these schemes are not claimed to be efficient. In this context the present results prove to be useful; they enable us to construct efficient quantum secret sharing schemes for many general access structures. More precisely, we show that an identically self-dual matroid that is representable over a finite field induces a pure state quantum secret sharing scheme with information rate one

Effectiveness of Mechanisms and Models of Coordination between Organizations, Agencies and Bodies Providing or Financing Health Services in Humanitarian Crises: A Systematic Review.

BACKGROUND: Effective coordination between organizations, agencies and bodies providing or financing health services in humanitarian crises is required to ensure efficiency of services, avoid duplication, and improve equity. The objective of this review was to assess how, during and after humanitarian crises, different mechanisms and models of coordination between organizations, agencies and bodies providing or financing health services compare in terms of access to health services and health outcomes. METHODS: We registered a protocol for this review in PROSPERO International prospective register of systematic reviews under number PROSPERO2014:CRD42014009267. Eligible studies included randomized and nonrandomized designs, process evaluations and qualitative methods. We electronically searched Medline, PubMed, EMBASE, Cochrane Central Register of Controlled Trials, CINAHL, PsycINFO, and the WHO Global Health Library and websites of relevant organizations. We followed standard systematic review methodology for the selection, data abstraction, and risk of bias assessment. We assessed the quality of evidence using the GRADE approach. RESULTS: Of 14,309 identified citations from databases and organizations' websites, we identified four eligible studies. Two studies used mixed-methods, one used quantitative methods, and one used qualitative methods. The available evidence suggests that information coordination between bodies providing health services in humanitarian crises settings may be effective in improving health systems inputs. There is additional evidence suggesting that management/directive coordination such as the cluster model may improve health system inputs in addition to access to health services. None of the included studies assessed coordination through common representation and framework coordination. The evidence was judged to be of very low quality. CONCLUSION: This systematic review provides evidence of possible effectiveness of information coordination and management/directive coordination between organizations, agencies and bodies providing or financing health services in humanitarian crises. Our findings can inform the research agenda and highlight the need for improving conduct and reporting of research in this field

Moderate Intensity Resistance Training Significantly Elevates Testosterone following Upper Body and Lower Body Bouts when Total Volume is held Constant

Introduction: It is unknown whether resistance training intensity or total volume of work affects the acute testosterone response to a greater extent. Purpose: Therefore, the circulating testosterone response was investigated following four resistance training protocols where total volume of work was held constant: moderate intensity (70% 1RM) upper body (bench press, bent barbell row, and military press), moderate intensity lower body (squat and deadlift), high intensity (90% 1RM) upper body, high intensity lower body. Methods: Total volume of work performed by each participant between protocols was maintained by adjusting the number of sets and or repetitions performed. Ten healthy, resistance trained men volunteered, and performed exercise protocols on separate days in a counterbalanced order. Capillary blood was obtained via finger stick at baseline (pre), immediately following the exercise session (post), and 1h post for the determination of testosterone concentration. Data were analyzed using a factorial ANOVA and significance was accepted at p≤ 0.05. Results:Both moderate intensity resistance protocols (upper and lower body) significantly increased testosterone concentration (p=0.026, and p=0.024 respectively), whereas the high intensity protocols elevated testosterone but failed to achieve significance (upper p=0.272, lower p=0.658). No difference was noted in post session testosterone concentration between upper and lower body protocols for either moderate (p=0.248) or high intensity (p=0.990). Conclusion: This may be useful for novice resistance trained individuals because it provides evidence that moderate intensity is sufficient to increase testosterone compared to high intensity protocols that could be associated with a greater risk of injury

Salivary cortisol and testosterone responses to high-intensity cycling before and after an 11-day intensified training period

This study examined salivary cortisol and testosterone responses to two, different high-intensity, ~30-min cycles separated by 2 h rest before and after an 11-day intensified training period. Twelve recreationally active, healthy males completed the study. Saliva samples were collected before, immediately after and 30 min after both bouts with salivary cortisol and testosterone concentrations assessed. Compared with pre-training blunted exercise-induced salivary cortisol, testosterone and cortisol/testosterone responses to both bouts post-training were observed (P 0.05). Fatigue and Burnout scores were higher post- compared with pre-training (P < 0.05). These high-intensity exercise bouts can detect altered hormonal responses following intensified training. This test could assess an athlete’s current hormonal status, reductions in salivary cortisol and testosterone responses suggestive of increased fatigue

Supporting good quality, community-based end-of-life care for people living with dementia: the SEED research programme including feasibility RCT

Background In the UK, most people with dementia die in the community and they often receive poorer end-of-life care than people with cancer. Objective The overall aim of this programme was to support professionals to deliver good-quality, community-based care towards, and at, the end of life for people living with dementia and their families. Design The Supporting Excellence in End-of-life care in Dementia (SEED) programme comprised six interlinked workstreams. Workstream 1 examined existing guidance and outcome measures using systematic reviews, identified good practice through a national e-survey and explored outcomes of end-of-life care valued by people with dementia and family carers (n = 57) using a Q-sort study. Workstream 2 explored good-quality end-of-life care in dementia from the perspectives of a range of stakeholders using qualitative methods (119 interviews, 12 focus groups and 256 observation hours). Using data from workstreams 1 and 2, workstream 3 used co-design methods with key stakeholders to develop the SEED intervention. Worksteam 4 was a pilot study of the SEED intervention with an embedded process evaluation. Using a cluster design, we assessed the feasibility and acceptability of recruitment and retention, outcome measures and our intervention. Four general practices were recruited in North East England: two were allocated to the intervention and two provided usual care. Patient recruitment was via general practitioner dementia registers. Outcome data were collected at baseline, 4, 8 and 12 months. Workstream 5 involved economic modelling studies that assessed the potential value of the SEED intervention using a contingent valuation survey of the general public (n = 1002). These data informed an economic decision model to explore how the SEED intervention might influence care. Results of the model were presented in terms of the costs and consequences (e.g. hospitalisations) and, using the contingent valuation data, a cost–benefit analysis. Workstream 6 examined commissioning of end-of-life care in dementia through a narrative review of policy and practice literature, combined with indepth interviews with a national sample of service commissioners (n = 20). Setting The workstream 1 survey and workstream 2 included services throughout England. The workstream 1 Q-sort study and workstream 4 pilot trial took place in North East England. For workstream 4, four general practices were recruited; two received the intervention and two provided usual care. Results Currently, dementia care and end-of-life care are commissioned separately, with commissioners receiving little formal guidance and training. Examples of good practice rely on non-recurrent funding and leadership from an interested clinician. Seven key components are required for good end-of-life care in dementia: timely planning discussions, recognising end of life and providing supportive care, co-ordinating care, effective working with primary care, managing hospitalisation, continuing care after death, and valuing staff and ongoing learning. Using co-design methods and the theory of change, the seven components were operationalised as a primary care-based, dementia nurse specialist intervention, with a care resource kit to help the dementia nurse specialist improve the knowledge of family and professional carers. The SEED intervention proved feasible and acceptable to all stakeholders, and being located in the general practice was considered beneficial. None of the outcome measures was suitable as the primary outcome for a future trial. The contingent valuation showed that the SEED intervention was valued, with a wider package of care valued more than selected features in isolation. The SEED intervention is unlikely to reduce costs, but this may be offset by the value placed on the SEED intervention by the general public. Limitations The biggest challenge to the successful delivery and completion of this research programme was translating the ‘theoretical’ complex intervention into practice in an ever-changing policy and service landscape at national and local levels. A major limitation for a future trial is the lack of a valid and relevant primary outcome measure to evaluate the effectiveness of a complex intervention that influences outcomes for both individuals and systems. Conclusions Although the dementia nurse specialist intervention was acceptable, feasible and integrated well with existing care, it is unlikely to reduce costs of care; however, it was highly valued by all stakeholders (professionals, people with dementia and their families) and has the potential to influence outcomes at both an individual and a systems level. Future work There is no plan to progress to a full randomised controlled trial of the SEED intervention in its current form. In view of new National Institute for Health and Care Excellence dementia guidance, which now recommends a care co-ordinator for all people with dementia, the feasibility of providing the SEED intervention throughout the illness trajectory should be explored. Appropriate outcome measures to evaluate the effectiveness of such a complex intervention are needed urgently. Trial registration Current Controlled Trials ISRCTN21390601. Funding This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full in Programme Grants for Applied Research, Vol. 8, No. 8. See the NIHR Journals Library website for further project information