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Background The detection of submicroscopic infections in low prevalence settings has become an increasingly important challenge for malaria elimination strategies. The current field rapid diagnostic tests (RDTs) for Plasmodium falciparum malaria are inadequate to detect low-density infections. Therefore, there is a need to develop more sensitive field diagnostic tools. In parallel, a highly sensitive laboratory reference assay will be essential to evaluate new diagnostic tools. Recently, the highly sensitive Alere™ Malaria Ag P.f ELISA (HS ELISA) was developed to detect P. falciparum histidine-rich protein 2 (HRP2) in clinical whole blood specimens. In this study, the analytical and clinical performance of the HS ELISA was determined using recombinant P. falciparum HRP2, P. falciparum native culture parasites, and archived highly pedigreed clinical whole blood specimens from Karen village, Myanmar and Nagongera, Uganda. Results The HS ELISA has an analytical sensitivity of less than 25 pg/mL and shows strong specificity for P. falciparum HRP2 when tested against P. falciparum native culture strains with pfhrp2 and pfhrp3 gene deletions. Additionally, the Z′-factor statistic of 0.862 indicates the HS ELISA as an excellent, reproducible assay, and the coefficients of variation for inter- and intra-plate testing, 11.76% and 2.51%, were acceptable. Against clinical whole blood specimens with concordant microscopic and PCR results, the HS ELISA showed 100% (95% CI 96.4–100) diagnostic sensitivity and 97.9% (95% CI 94.8–99.4) diagnostic specificity. For P. falciparum positive specimens with HRP2 concentrations below 400 pg/mL, the sensitivity and specificity were 100% (95% CI 88.4–100) and 88.9% (95% CI 70.8–97.6), respectively. The overall sensitivity and specificity for all 352 samples were 100% (CI 95% 96–100%) and 97.3% (CI 95% 94–99%). Conclusions The HS ELISA is a robust and reproducible assay. The findings suggest that the HS ELISA may be a useful tool as an affordable reference assay for new ultra-sensitive HRP2-based RDTs.

The Society for Ecological Restoration (SER) has long debated how to define best practices. We argue that a principles-first approach offers more flexibility for restoration practitioners than a standards-based approach, is consistent with the developmental stage of restoration, and functions more effectively at a global level. However, the solution is not as simple as arguing that one approach to professional practice is sufficient. Principles and standards can and do operate effectively together, but only if they are coordinated in a transparent and systematic way. Effective professional guidance results when standards anchored by principles function in a way that is contextual and evolving. Without that clear relation to principles, the tendency to promote performance standards may lead to a narrowing of restoration practice and reduction in the potential to resolve very difficult and diverse ecological and environmental challenges. We offer recommendations on how the evolving project of restoration policy by SER and other agencies and organizations can remain open and flexible.

Experimental data on laser-driven carbon C6+ ion acceleration with a peak intensity of 5 × 1020 W cm−2 are presented and compared for opaque target normal sheath acceleration (TNSA) and relativistically transparent laser–plasma interactions. Particle numbers, peak ion energy and conversion efficiency have been investigated for target thicknesses from 50 nm to 25µm using unprecedented full spectral beam profile line-out measurements made using a novel high-resolution ion wide-angle spectrometer. For thicknesses of about 200 nm, particle numbers and peak energy increase to 5 × 1011 carbon C 6+ particles between 33 and 700 MeV (60 MeV u−1 ), which is a factor of five higher in particle number than that observed for targets with micron thickness. For 200 nm thick targets, we find that the peak conversion efficiency is 6% and that up to 55% of the target under the laser focal spot is accelerated to energies above 33 MeV. This contrasts with the results for targets with micron thickness, where surface acceleration with TNSA is dominant. The experimental findings are consistent with two-dimensional particle-in-cell simulations.

This paper offers unique insights into the distribution of damage to bus shelters, in a single\ud case study area, Merseyside (UK). The geography of bus shelter damage is examined in\ud relation to the criminogenic and socio-economic characteristics of its neighbourhood, and\ud the local land use context. The findings suggest that shelter damage is related in a known\ud and predictable way to known characteristics of its neighbourhood, and that shelters in\ud areas with high levels of anti social behaviour and violence against the person are more\ud susceptible to bus shelter damage. Two key factors in the occurrence of bus shelter\ud damage appear to be lack of capable guardianships and the presence of youths. In relation\ud to the influence of land use, the presence of parks, children s play areas and schools\ud (particularly those whose unauthorised truancy levels were above the national average)\ud were positively correlated with shelter damage. By contrast, negative relationships were\ud found between shelter damage and the presence of pubs, clubs, and off-licenses. The\ud implications of these findings for crime prevention are then discussed, alongside some\ud potential avenues for future research.

Reducing Burglary Initiative EvaluationThe Reducing Burglary InitiativeIn 1998 the Home Office announced the Crime Reduction Programme. The programme wasintended to develop and implement an integrated approach to reducing crime and makingcommunities safer. The Reducing Burglary Initiative (RBI), launched in 1999, was one of thefirst parts of this programme to commence.The aims of the RBI are to: reduce burglary nationally by targeting areas with the worst domestic burglary problems; evaluate the cost effectiveness of the different approaches and; find out what works best where.Two hundred and forty seven burglary reduction projects have been funded, covering over2.1million households that suffered around 110,000 burglaries a year. Three distractionburglary projects have also been funded.The EvaluationThree consortia of universities have intensively evaluated the first round of 63 RBI projects.A further five projects from subsequent rounds of the RBI (rounds two and three) are alsobeing evaluated.This report is part of a series of studies examining burglary reduction practice beingpublished during 2003. Also to be published are a summary and full report on the overallimpact and cost-effectiveness of Round 1 of the RBI. Other themes to be covered in thisseries are: the delivery of burglary reduction projects; police detection strategies; publicity and awareness of burglary reduction schemes; and the use of alley-gates as a means to reduce burglary.

The effect of adding computer technology to an existing reproductive herd health program was studied. The data from twenty dairy herds already on reproductive program was entered onto a computer program designed to prepare action lists and to produce reports measuring reproductive performance. These reports were used to encourage, educate and critique dairy management. Measurements of seven reproductive parameters during a base period were compared with measurements 9 and 15 months later to determine if computer enhancement provided a useful tool for increasing breeding efficiency. Days from calving to conception were reduced from 111 to 101. Other parameters were unaffected., The Bovine Practitioner, No. 22 (1987 November)

Results from six continuous and semicontinuous black carbon (BC) and elemental carbon (EC) measurement methods are compared for ambient samples collected from December 2003 through November 2004 at the Fresno Supersite in California. Instruments included a multi-angle absorption photometer (MAAP; wavelength 670 nm); a dual-wavelength (wavelengths 370 and 880 nm) aethalometer; seven-color (wavelengths 370, 470, 520, 590, 660, 880, and 950 nm) aethalometers; the Sunset Laboratory carbon aerosol analysis field instrument; a photoacoustic light absorption analyzer (wavelength 1047 nm); and the R&P 5400 ambient carbon particulate monitor. All of these acquired BC or EC measurements over periods of 1 min to 1 hr. Twenty-fourhour integrated filter samples were also acquired and analyzed by the Interagency Monitoring of Protected Visual Environments (IMPROVE) thermal/optical reflectance carbon analysis protocol. Site-specific mass absorption efficiencies estimated by comparing light absorption with IMPROVE EC concentrations were 5.5m2/g for the MAAP, 10 m2/g for the aethalometer at a wavelength of 880 nm, and 2.3 m2/g for the photoacoustic analyzer; these differed from the default efficiencies of 6.5, 16.6, and 5m2/g, respectively. Scaling absorption by inverse wavelength did not provide equivalent light absorption coefficients among the instruments for the Fresno aerosol measurements. Ratios of light absorption at 370 nm to those at 880 nm from the aethalometer were nearly twice as high in winter as in summer. This is consistent with wintertime contributions from vehicle exhaust and from residential wood combustion, which is believed to absorb more shorter-wavelength light. To reconcile BC and EC measurements obtained by different methods, a better understanding is needed of the wavelength dependence of light-absorption and mass-absorption efficiencies and how they vary with different aerosol composition.

The output feedback pole placement problem of linear systems with static or dynamic compensators belongs to the classical problems in control theory and many theoretical and numerical research papers were already devoted to this problem. Although the considered systems are linear, the problem requires the solution of an over determined system of quadratic polynomial equations.

In the recent control literature there has been a great interest in controller design techniques which are robust with respect to plant perturbations. Crucial for all robustness studies is of course the availability of a “good metric” defined on the set of all plants. A metric is considered good if it can be easily computed and if it gives a measure of numerical robustness.

The following paper considers the problem of static output feedback for a linear, time invariant system. Starting from a geometric model a new algorithm for finding a linear feedback law is derived. The well known condition m + p - 1 ≥ n for generic pole placement given by Kimura [8] is improved using geometric arguments in linear spaces.