Nuclear pumped gas laser research

Nuclear pumping of lasers by fission-fragments from nuclear chain reactions is discussed. Application of the newly developed lasers to spacecraft propulsion or onboard power, to lunar bases for industrial processing, and to earth for utilization of power without pollution and hazards is envisioned. Emphasis is placed on the process by which the fission-fragement kinetic energy is converted into laser light

High resolution computation of the aerodynamics and acoustics of blade vortex interaction

In the present work, high resolution CFD simulations have been performed on an idealised problem of the interaction of an independently generated vortex with a rotor blade, including a case where the vortex directly impacts on the blade. The resulting blade pressures and acoustics are comprehensively compared against experimental measurements. Two different modelling approaches are used: the first is to impose the vortex as a perturbation to the velocity field, and the second is to fully resolve the vortex formation, evolution and its interaction with the blade. For a case in which the vortex passes near the blade surface, the the fully resolved approach is confirmed to accurately preserve the vortex structure. The far field acoustic predictions offered by the fully resolved approach are seen to be very accurate and definite improvements are observed in the computed blade pressures and acoustics over the imposed vortex approach and other similar works in the literature. For a case in which the vortex axis passes through the blade, the shape and width of the acoustic pulse in the far field is accurately represented by the fully resolved approach, while the magnitude is slightly underpredicted. The improvement in prediction offered by the fully resolved approach is because this method allows for a more realistic representation of phenomena, such as dynamic change in vortex structure and trajectory due to the blade passage, that become important when the vortex miss-distance becomes small

Non-equilibrium radiation nuclear reactor

An externally moderated thermal nuclear reactor is disclosed which is designed to provide output power in the form of electromagnetic radiation. The reactor is a gaseous fueled nuclear cavity reactor device which can operate over wide ranges of temperature and pressure, and which includes the capability of processing and recycling waste products such as long-lived transuranium actinides. The primary output of the device may be in the form of coherent radiation, so that the reactor may be utilized as a self-critical nuclear pumped laser

Magnetically controlled plasma accelerator Patent

Magnetically controlled plasma accelerator capable of ignition in low density gaseous environmen

Equivelar and d-Covered Triangulations of Surfaces. I

We survey basic properties and bounds for $q$-equivelar and $d$-covered triangulations of closed surfaces. Included in the survey is a list of the known sources for $q$-equivelar and $d$-covered triangulations. We identify all orientable and non-orientable surfaces $M$ of Euler characteristic $0>\chi(M)\geq -230$ which admit non-neighborly $q$-equivelar triangulations with equality in the upper bound $q\leq\Bigl\lfloor\tfrac{1}{2}(5+\sqrt{49-24\chi (M)})\Bigl\rfloor$. These examples give rise to $d$-covered triangulations with equality in the upper bound $d\leq2\Bigl\lfloor\tfrac{1}{2}(5+\sqrt{49-24\chi (M)})\Bigl\rfloor$. A generalization of Ringel's cyclic $7{\rm mod}12$ series of neighborly orientable triangulations to a two-parameter family of cyclic orientable triangulations $R_{k,n}$, $k\geq 0$, $n\geq 7+12k$, is the main result of this paper. In particular, the two infinite subseries $R_{k,7+12k+1}$ and $R_{k,7+12k+2}$, $k\geq 1$, provide non-neighborly examples with equality for the upper bound for $q$ as well as derived examples with equality for the upper bound for $d$.Comment: 21 pages, 4 figure

The role of evidence and the expert in contemporary processes of governance: the case of opioid substitution treatment policy in England

Background This paper is based on research examining stakeholder involvement in substitution treatment policy which was undertaken as part of the EU funded FP7 ALICE-RAP (Addictions and Lifestyles in Contemporary Europe – Reframing Addictions Project). In England, the research coincided with a policy shift towards a recovery orientated drug treatment framework and a heated debate surrounding the role of substitute prescribing. The study aimed to explore the various influences on the development of the new ‘recovery’ policy from the perspectives of the key stakeholders involved. Methods The paper is based on documentary analyses and key informant interviews with a range of stakeholders, including representatives of user organisations, treatment providers, civil servants, and members of expert committees. Results Drawing on the theoretical insights offered by Backstrand’s ‘civic science’ framework, the changing role of evidence and the position of experts in the processes of drugs policy governance are explored. ‘Evidence’ was used to problematise the issue of substitution treatment and employed to legitimise, justify and construct arguments around the possible directions of policy and practice. Conflicting beliefs about drug treatment and about motivation for policy change emerge in the argumentation, illustrating tensions in the governance of drug treatment and the power differentials separating different groups of stakeholders. Their role in the production of evidence also illustrates issues of power regarding the definition and development of ‘usable knowledge’. There were various attempts at greater representation of different forms of evidence and participation by a wider group of stakeholders in the debates surrounding substitution treatment. However, key national and international experts and the appointment of specialist committees continued to play dominant roles in building consensus and translating scientific evidence into policy discourse. Conclusion Substitution treatment policy has witnessed a challenge to the dominance of ‘scientific evidence’ within policy decision making, but in the absence of alternative evidence with an acceptable credibility and legitimacy base, traditional notions of what constitutes evidence based policy persist and there is a continuing lack of recognition of ‘civic science’

Granule Cell Dispersion in Human Temporal Lobe Epilepsy: Proteomics investigation of neurodevelopmental migratory pathways

Granule cell dispersion (GCD) is a common pathological feature observed in the hippocampus of patients with Mesial Temporal Lobe Epilepsy (MTLE). Pathomechanisms underlying GCD remain to be elucidated, but one hypothesis proposes aberrant reactivation of neurodevelopmental migratory pathways, possibly triggered by febrile seizures. This study aims to compare the proteomes of basal and dispersed granule cells in the hippocampus of eight MTLE patients with GCD to identify proteins that may mediate GCD in MTLE. Quantitative proteomics identified 1882 proteins, of which 29% were found in basal granule cells only, 17% in dispersed only and 54% in both samples. Bioinformatics analyses revealed upregulated proteins in dispersed samples were involved in developmental cellular migratory processes, including cytoskeletal remodelling, axon guidance and signalling by Ras homologous (Rho) family of GTPases (P<0.01). The expression of two Rho GTPases, RhoA and Rac1, was subsequently explored in immunohistochemical and in situ hybridisation studies involving eighteen MTLE cases with or without GCD, and three normal post mortem cases. In cases with GCD, most dispersed granule cells in the outer-granular and molecular layers have an elongated soma and bipolar processes, with intense RhoA immunolabelling at opposite poles of the cell soma, while most granule cells in the basal granule cell layer were devoid of RhoA. A higher density and percentage of cells expressing RhoA was observed in cases with GCD than without GCD (P<0.004). In GCD cases, the density and percentage of cells expressing RhoA was significantly higher in the inner molecular layer than granule cell layer (P<0.026), supporting proteomic findings. In situ hybridisation studies using probes against RHOA and RAC1 mRNAs revealed fine peri- and nuclear puncta in granule cells of all cases. The density of cells expressing RHOA mRNAs were significantly higher in the inner molecular layer of cases with GCD than without GCD(P=0.05). In summary, our study has found limited evidence for ongoing adult neurogenesis in the hippocampus of patients with MTLE, but evidence of differential dysmaturation between dispersed and basal granule cells has been demonstrated, and elevated expression of Rho GTPases in dispersed granule cells may contribute to the pathomechanisms underpinning GCD in MTLE

Workforce development: is there a paradigm shift?

Editorial for a Special Issue on Workforce Development in the alcohol and other drugs field published in Drugs: Education, Prevention & Policy

Challenges to providing culturally sensitive drug interventions for black and Asian minority ethnic (BAME) groups within UK youth justice systems

To explore how substance use practitioners intervene with ethnically and culturally diverse groups of young people in contact with the youth justice system. Telephone, face to face interviews and a focus group were conducted. Data were analysed thematically using a frame reflective theoretical approach. Practitioners tended to offer individualised interventions to young people in place of culturally specific approaches partly due to a lack of knowledge, training or understanding of diverse cultural needs, and for practical and resource reasons. Practitioners reject the official narrative of BAME youth in the justice system as dangerous and in need of control, viewing them instead as vulnerable and in need of support but report they lack experience, and sufficient resources, in delivering interventions to diverse groups. There is little information regarding how practitioners respond to diversity in their daily practice. This paper is an exploration of how diversity is framed and responded to in the context of youth substance use and criminal justice

Framing 'drug prevention' for young people in contact with the criminal justice system in England: views from practitioners in the field

Drawing on the work of Rein and Schon (1993; 1996), we explore the ways in which ‘young people’, ‘vulnerability’, ‘risk’, ‘prevention’ and ‘prevention practice’ were defined and framed by practitioners engaged in the design, delivery and commissioning of drug prevention interventions for young people in contact with the criminal justice system. We argue that practitioners describe their work in terms of both a preventative frame – based on a ‘deficit’ model - and a transformative praxis frame, more in line with an increasing shift towards ‘positive youth justice’ where practitioners aspire to actively involve the young person in a process of change. The implications of those, often competing, frames are discussed in relation to the development of prevention approaches and the challenges in designing drugs prevention for this group of young people. The paper is based on interviews and focus groups with thirty-one practitioners in England and is part of the EU funded EPPIC project (Exchanging Prevention Practices on Polydrug Use among Youth in Criminal Justice Systems 2017-2020)