Antibody and B cell responses to Plasmodium sporozoites

Antibodies are capable of blocking infection of the liver by Plasmodium sporozoites. Accordingly the induction of anti-sporozoite antibodies is a major aim of various vaccine approaches to malaria. In recent years our knowledge of the specificity and quantities of antibodies required for protection has been greatly expanded by clinical trials of various whole sporozoite and subunit vaccines. Moreover, the development of humanized mouse models and transgenic parasites have also aided our ability to assess the specificity of antibodies and their ability to block infection. Nonetheless, considerable gaps remain in our knowledge - in particular in understanding what antigens are recognized by infection blocking antibodies and in knowing how we can induce robust, long-lived antibody responses. Maintaining high levels of circulating antibodies is likely to be of primary importance, as antibodies must block infection in the short time it takes for sporozoites to reach the liver from the skin. It is clear that a better understanding of the development of protective B cell-mediated immunity will aid the development and refinement of malaria vaccines.The authors acknowledge the support of the Australian National University and Perpetual Foundation for research in the Cockburn laboratory

Observation of a two-dimensional spin-lattice in non-magnetic semiconductor heterostructures

Tunable magnetic interactions in high-mobility nonmagnetic semiconductor heterostructures are centrally important to spin-based quantum technologies. Conventionally, this requires incorporation of "magnetic impurities" within the two-dimensional (2D) electron layer of the heterostructures, which is achieved either by doping with ferromagnetic atoms, or by electrostatically printing artificial atoms or quantum dots. Here we report experimental evidence of a third, and intrinsic, source of localized spins in high-mobility GaAs/AlGaAs heterostructures, which are clearly observed in the limit of large setback distance (=80 nm) in modulation doping. Local nonequilibrium transport spectroscopy in these systems reveals existence of multiple spins, which are located in a quasi-regular manner in the 2D Fermi sea, and mutually interact at temperatures below 100 milliKelvin via the Ruderman-Kittel-Kasuya-Yosida (RKKY) indirect exchange. The presence of such a spin-array, whose microscopic origin appears to be disorder-bound, simulates a 2D lattice-Kondo system with gate-tunable energy scales.Comment: 7 pages + 4 figs. To appear in Nature Physics. This is the original submitted version. Final version will be posted six months after publication. The Supplementary Information can be downloaded from: http://www.physics.iisc.ernet.in/~arindam/Supplementary_Information_NPHYS-2006-08-0 0812B.pd

An exploratory international comparison of professional confidence in volunteer policing

Police volunteers are an important asset to communities and policing agencies, but have been relatively understudied in academic literature. Similar models of police volunteers have developed in the United States and the United Kingdom, but differ in the level of their operational preparedness and training. Across England and Wales standardized policies have been established which govern the recruitment, training, and deployment of volunteer police officers, but in the United States there has been consistent resistance from local governments to develop national standards for reserve and auxiliary police. This current study examines the confidence of volunteer police officers serving in two police forces, one within the North East of England, and one within central Florida. The study utilizes vignettes to describe realistic situations that might be encountered by volunteer police on patrol in either country, and asked respondents to report their confidence within the scenario to perform certain functions based upon aspects drawn from the National Occupational Standards (NOS) expected of a regular police officer across the UK. Results of the study show that while both groups of volunteer officers in the study are confident in their professional abilities to handle issues at a policing scene, differences in training may have resulted in UK volunteer officers feeling less confident about interviewing and administrative paperwork skills than their US counterparts. This paper adds to the very limited literature about volunteer policing and identifies recommendations in relation to volunteer officer training and confidence to perform certain functions of their policing roles

Evidence Based Policing for crime prevention in England and Wales: Perception and use by new police recruits

Evidence-based policing is an integral part of the police approach to crime prevention work being closely associated with the problem solving approach as developed by Goldstein (Problem-oriented policing, McGraw-Hill, New York, 1990) This research explores the effect of the new initial police entry programmes, co-delivered in partnerships between higher education and police forces, on the application of evidence-based policing (EBP) in the workplace. It also considers the impact of team leaders and supervisors on this adoption. The study utilised a survey of new student police constables undergoing the new higher education qualifications programme from five different police forces in England and Wales. Findings suggest that EBP appears to be applied in the workplace, and that the combination of higher education and work-based practice will continue to influence the adoption of EBP by new police constables. In particular is the role of police leaders in this aspect. This in turn may embed it into practice despite any cultural resistance, thus enhancing the crime prevention role of the police