Tritium supply and use: a key issue for the development of nuclear fusion energy

Full power operation of the International Thermonuclear Experimental Reactor (ITER) has been delayed and will now begin in 2035. Delays to the ITER schedule may affect the availability of tritium for subsequent fusion devices, as the global CANDU-type fission reactor fleet begins to phase out over the coming decades. This study provides an up to date account of future tritium availability by incorporating recent uncertainties over the life extension of the global CANDU fleet, as well as considering the potential impact of tritium demand by other fusion efforts. Despite the delays, our projections suggest that CANDU tritium remains sufficient to support the full operation of ITER. However, whether there is tritium available for a DEMO reactor following ITER is largely uncertain, and is subject to numerous uncontrollable externalities. Further tritium demand may come from any number of private sector “compact fusion” start-ups which have emerged in recent years, all of which aim to accelerate the development of fusion energy. If the associated technical challenges can be overcome, compact fusion programmes have the opportunity to use tritium over the next two decades whilst it is readily available, and before full power DT operation on ITER starts in 2035. Assuming a similar level of performance is achievable, a compact fusion development programme, using smaller reactors operating at lower fusion power, would require smaller quantities of tritium than the ITER programme, leaving sufficient tritium available for multiple concepts to be developed concurrently. The development of concurrent fusion concepts increases the chances of success, as it spreads the risk of failure. Additionally, if full tritium breeding capability is not expected to be demonstrated in DEMO until after 2050, an opportunity exists for compact fusion programmes to incorporate tritium breeding technology in nearer-term devices. DD start-up, which avoids the need for external tritium for reactor start-up, is dependent upon full tritium breeding capability, and may be essential for large-scale commercial roll-out of fusion energy. As such, from the standpoint of availability and use of external tritium, a compact route to fusion energy may be more advantageous, as it avoids longer-term complications and uncertainties in the future supply of tritium

Complete classification of purely magnetic, non-rotating and non-accelerating perfect fluids

Recently the class of purely magnetic non-rotating dust spacetimes has been shown to be empty (Wylleman, Class. Quant. Grav. 23, 2727). It turns out that purely magnetic rotating dust models are subject to severe integrability conditions as well. One of the consequences of the present paper is that also rotating dust cannot be purely magnetic when it is of Petrov type D or when it has a vanishing spatial gradient of the energy density. For purely magnetic and non-rotating perfect fluids on the other hand, which have been fully classified earlier for Petrov type D (Lozanovski, Class. Quant. Grav. 19, 6377), the fluid is shown to be non-accelerating if and only if the spatial density gradient vanishes. Under these conditions, a new and algebraically general solution is found, which is unique up to a constant rescaling, which is spatially homogeneous of Bianchi type $VI_0$, has degenerate shear and is of Petrov type I($M^\infty)$ in the extended Arianrhod-McIntosh classification. The metric and the equation of state are explicitly constructed and properties of the model are briefly discussed. We finally situate it within the class of normal geodesic flows with degenerate shear tensor.Comment: 12 pages; introduction partly rewritten, notation made more clear, table of results adde

Research and knowledge transfer priorities in developmental coordination disorder: Results from consultations with multiple stakeholders

Abstract : Background: Priority‐setting is a way to focus research and knowledge translation (KT) efforts for community‐based research partnerships (CBRP). Objective: To identify the developmental coordination disorder (DCD) research and KT priorities of stakeholders in Quebec, Canada, and their perceptions regarding the implementation of a CBRP. Design: An advisory committee oversaw the research process including an online survey and four community forums. Setting and participants: The survey was posted online and four community forums were organized. Participants included parents of children with DCD, adults with DCD, health professionals and school staff. Main variables: Stakeholder generated research and KT priorities, and optimal CBPR conditions. Outcome measures: Participants selected their top five priorities based on a predefined list of 16 research and 12 KT priorities determined in collaboration with the advisory committee. They also rated the importance of various CBRP conditions. Preliminary survey results were discussed during the forums. Results: Survey participants (n = 395) identified interwoven research and KT priorities where access to services was considered to be essential: supporting children at school; improving DCD identification and diagnosis; preventing secondary consequences; improving the organization of services and implementing effective services. Forum participants (n = 52) confirmed the relevance of these priorities and supported the establishment of a CBRP inclusive of all stakeholders to improve DCD services, research and KT. Discussion and conclusions: A general consensus emerged among all groups, but adults with DCD were more concerned with employment than were the other stakeholder groups. These findings are presently being used to shape an ongoing, online CBRP

Playing safe: Assessing the risk of sexual abuse to elite child athletes

Young athletes frequently suffer from being seen as athletes first and children second. This has consequences for their legal, civil and human rights as children (Kelly et al., 1995) and for the way in which sport organisations choose to intervene on their behalf to protect them from physical, psychological and sexual abuses (Brackenridge, 1994). Sport careers peak at different ages depending on the sport: in some, children as young as 12 or 13 may reach the highest levels of competitive performance; in others, full maturity as an athlete may come late into adulthood or even middle age. Recognition of this variation has given rise to the concept of ‘sport age’ (Kirby, 1986) referring to sport-specific athlete development. This concept is of significance in helping to identify the developmental process in terms of athletic, rather than chronological, maturity. The risk of sexual abuse in sport, formerly ignored or denied, has now been documented in a number of studies, using both quantitative and qualitative methods (Kirby & Greaves, 1996; Brackenridge, 1997; Volkwein, 1996). Drawing on data from these studies and from the previous work on sport age and athletic maturation, this paper proposes a possible means of identifying and assessing relative risk of sexual abuse to elite young athletes in selected sports. The concept of a ‘stage of imminent achievement’ (SIA) is proposed as the period of peak vulnerability of young athletes to sexual abuse

Examining the impact of health research facilitated by small peer-reviewed research operating grants in a women's and children's health centre

Abstract Background There has been limited research on the impact of research funding for small, institutional grants. The IWK Health Centre, a children and women's hospital in Maritime Canada, provides small amounts (up to $15,000) of research funding for staff and trainees at all levels of experience through its Research Operating Grants. These grants are rigorously peer-reviewed. To evaluate the impact of these grants, an assessment was completed of several different areas of impact. Findings An online questionnaire was sent to 64 Principal Investigators and Co-Investigators from Research Operating Grants awarded from 2004 to 2006. The questionnaire was designed to assess five areas of potential impact: (1) research, (2) policy, (3) practice, (4) society and (5) personal. Research impact reported by participants included publications (72%), presentations (82%) and knowledge transfer beyond the traditional formats (51%). Practice impact was reported by 67% of participants, policy impact by 15% and societal impact by 18%. All participants reported personal impact. Conclusions Small research grants yield similar impacts to relatively large research grants. Regardless of the total amount of research funds awarded, rigorously peer-reviewed research projects have the potential for significant impact at the level of knowledge transfer and changes in clinical practice and policy. Additional findings in the present research indicate that small awards have the potential to have significant impact on the individual grant holder across a variety of capacity building variables. These personal impacts are particularly noteworthy in the context of developing the research programs of novice researchers.</p

Hubungan Status Gizi Dengan Usia Menarche Pada Remaja Putri Di SMP Negeri 6 Tidore Kepulauan

. Background : Adolescence isatransition periodbetweenchildhoodandadulthood,is a time ofphysical maturity, cognitive, social andemotional. In young women, pubertyis oftenmarked bymenarche.Menarcheisthefirstmenstruationoccurs, whichis the hallmark ofmaturity ofa woman who ishealthyandnot pregnant. Menarcheusuallyoccurs at age11-13years. There are manyfactors that affectthe age ofmenarche,one of them isnutritionalstatus. This research was aimed to know the relationship nutritional status with age of menarche in young women at 6 Junior High School of Tidore Islands. The research methodsanalytical survey usingcross sectionaldesign. This research was conducted in 6 Junior High School of Tidore Islands on November 30 - December 8, 2015. Population is 97 students.Sampling technique is the total sampling with a sample size of 97 students. The instrument of this research used questionnaire, scales and height measuring devices.The data analysis is done with using the chi-square test, at the 95% significance level (á 0.05) showed the value of ñ=0.000, this value is smaller than á = 0.05. Conclusion : there is a relationship of nutritional status with age of menarche in young women at 6 Junior High School of Tidore Islands.Advice for young women to maintain normal nutritional status to achieve the normal age of menarche

Conservative management versus open reduction and internal fixation for mid-shaft clavicle fractures in adults - The Clavicle Trial: Study protocol for a multicentre randomized controlled trial

Background: Clavicle fractures account for around 4% of all fractures and up to 44% of fractures of the shoulder girdle. Fractures of the middle third (or mid-shaft) account for approximately 80% of all clavicle fractures. Management of this group of fractures is often challenging and the outcome can be unsatisfactory. In particular it is not clear whether surgery produces better outcomes than non-surgical management. Currently there is much variation in the use of surgery and a lack of good quality evidence to inform our decision.Methods/Design: We aim to undertake a multicentre randomised controlled trial evaluating the effectiveness and safety of conservative management versus open reduction and internal fixation for displaced mid-shaft clavicle fractures in adults. Surgical treatment will be performed using the Acumed clavicle fixation system. Conservative management will consist of immobilisation in a sling at the side in internal rotation for 6 weeks or until clinical or radiological union. We aim to recruit 300 patients. These patients will be followed-up for at least 9 months. The primary endpoint will be the rate of non-union at 3 months following treatment. Secondary endpoints will be limb function measured using the Constant-Murley Score and the Disabilities of the Arm, Shoulder and Hand (DASH) Score at 3 and 9 months post-operatively.Discussion: This article presents the protocol for a multicentre randomised controlled trial. It gives extensive details of, and the basis for, the chosen methods, and describes the key measures taken to avoid bias and to ensure validity.Trial Registration: United Kingdom Clinical Research Network ID: 8665. The date of registration of the trial is 07/09/2006. The date the first patient was recruited is 18/12/2007. © 2011 Longo et al; licensee BioMed Central Ltd