The dilation aided single-line-of-sight x-ray camera for the National Ignition Facility: Characterization and fielding.

Crystal x-ray imaging is frequently used in inertial confinement fusion and laser-plasma interaction applications as it has advantages compared to pinhole imaging, such as higher signal throughput, better achievable spatial resolution, and chromatic selection. However, currently used x-ray detectors are only able to obtain a single time resolved image per crystal. The dilation aided single-line-of-sight x-ray camera described here was designed for the National Ignition Facility (NIF) and combines two recent diagnostic developments, the pulse dilation principle used in the dilation x-ray imager and a ns-scale multi-frame camera that uses a hold and readout circuit for each pixel. This enables multiple images to be taken from a single-line-of-sight with high spatial and temporal resolution. At the moment, the instrument can record two single-line-of-sight images with spatial and temporal resolution of 35 µm and down to 35 ps, respectively, with a planned upgrade doubling the number of images to four. Here we present the dilation aided single-line-of-sight camera for the NIF, including the x-ray characterization measurements obtained at the COMET laser, as well as the results from the initial timing shot on the NIF.

Implementing time resolved electron temperature capability at the NIF using a streak camera.

A new capability at the National Ignition Facility (NIF) has been implemented to measure the temperature of x-ray emitting sources. Although it is designed primarily for Inertial Confinement Fusion (ICF), it can be used for any hot emitting source that is well modeled. The electron temperature (Te) of the hot spot within the core of imploded ICF capsules is an effective indicator of implosion performance. Currently, there are spatially and temporally integrated Te inferences using image plates. A temporally resolved measurement of Te will help elucidate the mechanisms for hot spot heating and cooling such as conduction to fuel, alpha-heating, mix, and radiative losses. To determine the temporally resolved Te of hot spots, specific filters are added to an existing x-ray streak camera "streaked polar instrumentation for diagnosing energetic radiation" to probe the emission spectrum during the x-ray burn history of implosions at the NIF. One of the difficulties in inferring the hot spot temperature is the attenuation of the emission due to opacity from the shell and fuel. Therefore, a series of increasingly thick titanium filters were implemented to isolate the emission in specific energy regions that are sensitive to temperatures above 3 keV while not significantly influenced by the shell/fuel attenuation. Additionally, a relatively thin zinc filter was used to measure the contribution of colder emission sources. Since the signal levels of the emission through the thicker filters are relatively poor, a dual slit (aperture) was designed to increase the detected signal at the higher end of the spectrum. Herein, the design of the filters and slit is described, an overview of the solving technique is provided, and the initial electron temperature results are reported.

Towards canine rabies elimination: Economic comparisons of three project sites.

An appreciation of the costs of implementing canine rabies control in different settings is important for those planning new or expanded interventions. Here we compare the costs of three canine rabies control projects in South Africa, the Philippines and Tanzania to identify factors that influence the overall costs of rabies control efforts. There was considerable variation in the cost of vaccinating each dog, but across the sites these were lower where population density was higher, and later in the projects when dog vaccination coverage was increased. Transportation costs comprised a much higher proportion of total costs in rural areas and where house-to-house vaccination campaigns were necessary. The association between the cost of providing PEP and human population density was less clear. The presence of a pre-existing national rabies management programme had a marked effect on keeping infrastructure and equipment costs for the project low. Finally, the proportion of the total costs of the project provided by the external donor was found to be low for the projects in the Philippines and South Africa, but likely covered close to the complete costs of the project in Tanzania. The detailed economic evaluation of three recent large-scale rabies control pilot projects provides the opportunity to examine economic costs across these different settings and to identify factors influencing rabies control costs that could be applied to future projects.

Factors predictive of survival and estimated years of life lost in the decade following nontraumatic and traumatic spinal cord injury.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: To identify factors predictive of survival after spinal cord injury (SCI). SETTING: Tertiary care institution. METHODS: Multiple-variable Cox proportional hazards regression analysis for 759 patients with SCI (535 nontraumatic and 221 traumatic) included age, sex, completeness of injury, level of injury, functional independence measure (FIM) scores, rehabilitation length of stay and SCI cause. Estimated years of life lost in the decade after injury was calculated for patients vs uninjured controls. RESULTS: Median follow-up was 11.4 years. Population characteristics included paraplegia, 58%; complete injury, 11%; male sex, 64%; and median rehabilitation length of stay, 16 days. Factors independently predictive of decreased survival were increased age (+10 years; hazard ratio (HR (95% CI)), 1.6 (1.4-1.7)), male sex (1.3 (1.0-1.6)), lower dismissal FIM score (-10 points; 1.3 (1.2-1.3)) and all nontraumatic causes. Metastatic cancer had the largest decrease in survival (HR (95% CI), 13.3 (8.7-20.2)). Primary tumors (HR (95% CI), 2.5 (1.7-3.8)), vascular (2.5 (1.6-3.8)), musculoskeletal/stenosis (1.7 (1.2-2.5)) and other nontraumatic SCI (2.3 (1.5-3.6)) were associated with decreased survival. Ten-year survival was decreased in nontraumatic SCI (mean (s.d.), 1.8 (0.3) years lost), with largest decreases in survival for metastatic cancer and spinal cord ischemia. CONCLUSIONS: Age, male sex and lower dismissal FIM score were associated with decreased survival, but neither injury severity nor level was associated with it. Survival after SCI varies depending on SCI cause, with survival better after traumatic SCI than after nontraumatic SCI. Metastatic cancer and vascular ischemia were associated with the greatest survival reduction.

Towards Canine Rabies Elimination in Cebu, Philippines: Assessment of Health Economic Data.

Rabies is endemic in the Philippines. In 2010, with support from the Bill and Melinda Gates Foundation, a canine rabies elimination project was initiated in the Philippine Archipelago of Visayan. We conducted an analysis of dog vaccination and human PEP costs for dog bite patients in a highly urbanized area and a low-income rural municipality in Cebu Province, Philippines, from 2010 to 2012. Our findings indicated that eliminating rabies in dogs through mass vaccination is more cost-effective than treating rabies exposures in humans. The average costs (in USD) per human life saved through PEP were $1620.28 in Cebu City and $1498 in Carmen. Costs per dog vaccinated ranged from $1.18 to $5.79 in Cebu City and $2.15 to $3.38 in Carmen. Mass dog vaccination campaigns conducted in each village were more cost-effective than fixed-site campaigns. The costs of dog vaccination can be reduced further through bulk vaccine purchase by the national government or large donor agency, for example the BMGF. As communities achieve canine rabies elimination, more judicious use of PEP will result in significant public savings. The study affirms the willingness of local governments to invest and reassure donors of their cooperation and resource contribution to sustain disease elimination efforts.

Towards Canine Rabies Elimination in South-Eastern Tanzania: Assessment of Health Economic Data.

An estimated 59 000 people die annually from rabies, keeping this zoonosis on the forefront of neglected diseases, especially in the developing world. Most deaths occur after being bitten by a rabid dog. Those exposed to a suspect rabid animal should receive appropriate post-exposure prophylaxis (PEP) or risk death. However, vaccination of dogs to control and eliminate canine rabies at the source has been implemented in many places around the world. Here, we analysed the vaccination and cost data for one such campaign in the area surrounding and including Dar es Salaam, Tanzania and estimated the cost per dog vaccinated. We also estimated the cost of human PEP. We found that the cost per dog vaccinated ranged from $2.50 to $22.49 across districts and phases, with the phase average ranging from $7.30 to $11.27. These figures were influenced by over purchase of vaccine in the early phases of the programme and the significant costs associated with purchasing equipment for a programme starting from scratch. The cost per human PEP course administered was approximately $24.41, with the average patient receiving 2.5 of the recommended four vaccine doses per suspect bite. This study provides valuable financial insights into programme managers and policymakers working towards rabies elimination.

Structured photocathodes for improved high-energy x-ray efficiency in streak cameras.

We have designed and fabricated a structured streak camera photocathode to provide enhanced efficiency for high energy X-rays (1-12 keV). This gold coated photocathode was tested in a streak camera and compared side by side against a conventional flat thin film photocathode. Results show that the measured electron yield enhancement at energies ranging from 1 to 10 keV scales well with predictions, and that the total enhancement can be more than 3×. The spatial resolution of the streak camera does not show degradation in the structured region. We predict that the temporal resolution of the detector will also not be affected as it is currently dominated by the slit width. This demonstration with Au motivates exploration of comparable enhancements with CsI and may revolutionize X-ray streak camera photocathode design.

Simulated performance of the optical Thomson scattering diagnostic designed for the National Ignition Facility.

An optical Thomson scattering diagnostic has been designed for the National Ignition Facility to characterize under-dense plasmas. We report on the design of the system and the expected performance for different target configurations. The diagnostic is designed to spatially and temporally resolve the Thomson scattered light from laser driven targets. The diagnostic will collect scattered light from a 50 × 50 × 200 µm volume. The optical design allows operation with different probe laser wavelengths. A deep-UV probe beam (λ0 = 210 nm) will be used to Thomson scatter from electron plasma densities of ∼5 × 1020 cm-3 while a 3ω probe will be used for plasma densities of ∼1 × 1019 cm-3. The diagnostic package contains two spectrometers: the first to resolve Thomson scattering from ion acoustic wave fluctuations and the second to resolve scattering from electron plasma wave fluctuations. Expected signal levels relative to background will be presented for typical target configurations (hohlraums and a planar foil).

The design of the optical Thomson scattering diagnostic for the National Ignition Facility.

The National Ignition Facility (NIF) is a 192 laser beam facility designed to support the Stockpile Stewardship, High Energy Density and Inertial Confinement Fusion (ICF) programs. We report on the design of an Optical Thomson Scattering (OTS) diagnostic that has the potential to transform the community's understanding of NIF hohlraum physics by providing first principle, local, time-resolved measurements of under-dense plasma conditions. The system design allows operation with different probe laser wavelengths by manual selection of the appropriate beam splitter and gratings before the shot. A deep-UV probe beam (λ0-210 nm) will be used to optimize the scattered signal for plasma densities of 5 × 1020 electrons/cm3 while a 3ω probe will be used for experiments investigating lower density plasmas of 1 × 1019 electrons/cm3. We report the phase I design of a two phase design strategy. Phase I includes the OTS telescope, spectrometer, and streak camera; these will be used to assess the background levels at NIF. Phase II will include the design and installation of a probe laser.

Improving the off-axis spatial resolution and dynamic range of the NIF X-ray streak cameras (invited).

We report simulations and experiments that demonstrate an increase in spatial resolution of the NIF core diagnostic x-ray streak cameras by at least a factor of two, especially off axis. A design was achieved by using a corrector electron optic to flatten the field curvature at the detector plane and corroborated by measurement. In addition, particle in cell simulations were performed to identify the regions in the streak camera that contribute the most to space charge blurring. These simulations provide a tool for convolving synthetic pre-shot spectra with the instrument function so signal levels can be set to maximize dynamic range for the relevant part of the streak record.

Towards Canine Rabies Elimination in KwaZulu-Natal, South Africa: Assessment of Health Economic Data.

Rabies remains a significant problem throughout much of the developing world. An estimated 69 000 people die annually from exposure to rabies. Most of these deaths are the result of being bitten by a rabid dog. Mass vaccination campaigns targeting dogs have been implemented around the world in an attempt to control or eliminate canine rabies. We analysed the vaccination and cost data for a campaign in the KwaZulu-Natal province of South Africa; we found that the cost per dog vaccinated to be $6.61 for mass campaigns and $5.41 for local campaigns. We also estimated the cost of human post-exposure prophylaxis (PEP). The cost of PEP is approximately $64.50 on average per patient, and $333 on average for the 9% of patients who receive RIG. We also found that the districts that vaccinated the most dogs per capita experienced the highest rates of human treatment and thus had the highest PEP costs.

X-ray streak camera cathode development and timing accuracy of the 4ω ultraviolet fiducial system at the National Ignition Facility.

The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an accuracy of 2% in the velocity measurement, which translates to a ±2 ps temporal accuracy over any 300 ps interval for the streak camera. In order to achieve this, a 4ω (263 nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, titanium, gold, and silver photocathode materials have been tested. Aluminum showed the highest relative quantum efficiency, with five times more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data were analyzed to determine the centroiding statistical accuracy for incident laser pulse energies of 1 and 10 nJ, showing an accuracy of ±1.6 ps and ±0.7 ps, respectively.

High performance imaging streak camera for the National Ignition Facility.

An x-ray streak camera platform has been characterized and implemented for use at the National Ignition Facility. The camera has been modified to meet the experiment requirements of the National Ignition Campaign and to perform reliably in conditions that produce high electromagnetic interference. A train of temporal ultra-violet timing markers has been added to the diagnostic in order to calibrate the temporal axis of the instrument and the detector efficiency of the streak camera was improved by using a CsI photocathode. The performance of the streak camera has been characterized and is summarized in this paper. The detector efficiency and cathode measurements are also presented.

Effect of varying levels of fatty acids from palm oil on feed intake and milk production in Holstein cows.

To determine the optimum feeding level of fatty acids of palm oil (PALM; Energizer RP10; 86.6% palmitic acid) on milk production, lactating cows (n = 18) were randomly assigned to a treatment sequence in replicated 4 x 4 Latin squares. Animals were assigned to squares by parity (3 multiparous and 1 primiparous squares with primiparous in the incomplete square). The 4 diets were designed to provide 0, 500, 1,000, and 1,500 g of PALM per day. Cows were fed individually with feed intake measured daily. Each period lasted 16 d with milk production and composition determined the final 2 d. Milk production, milk composition and feed intake data were analyzed using the MIXED procedure of SAS. Milk yields were 30.9, 34.0, 34.2, and 34.2 kg/ d (SEM = 1.9) for the 0, 500, 1,000, and 1,500 g levels, respectively. Milk yield was increased by the addition of PALM; however, there were no differences among the levels of PALM. Milk fat percentage was also increased from 3.44% for 0 g to 3.95% (SEM = 0.17) across all levels of PALM but there were no differences among the PALM treatments. Dry matter intakes were 23.3, 26.4, 24.7, and 23.8 kg/d (SEM = 1.4) for the 0, 500, 1,000 and 1,500 g levels, respectively. The addition of PALM increased milk yield and milk fat percentage, and no adverse effects on dry matter intake were observed.

Cellulitis incidence in a defined population.

A population-based insurance claims database was used to examine cellulitis incidence, anatomical sites of infection, complicating diagnoses, source of health service, and recurrence rates. Insurance claim files were searched for cellulitis ICD-9-CM codes 681.0-682.9. Complications of cellulitis including erysipelas, lymphadenitis, lymphangitis, and necrotizing fasciitis were also identified by ICD-9-CM codes. We found a cellulitis incidence rate of 24.6/1000 person-years, with a higher incidence among males and individuals aged 45-64 years. The most common site of infection was the lower extremity (39.9%). The majority of patients were seen in an outpatient setting (73.8%), and most (82.0%) had only one episode of cellulitis during the 5-year period studied. There was a very low incidence of cellulitis complications, including necrotizing fasciitis. Cellulitis is fairly common, usually treated in outpatient settings, and is infrequently complicated by erysipelas, lymphadenitis, lymphangitis, or necrotizing fasciitis.

HIV partner notification: a 2002 Victorian audit.

This audit was carried out in August 2003 and examined HIV notification data in Victoria. We aimed to determine the proportion of partners reported as being traced from newly diagnosed HIV individuals, the type of contact tracing used and identify the number of HIV cases newly diagnosed from contact tracing. We compared men who have sex with men (MSM) with all other newly diagnosed HIV individuals in Victoria (non-MSM). Of the 215 newly diagnosed HIV-positive individuals, 49% (n = 105) could potentially carry out contact tracing. There was a difference between MSM and non-MSM in the proportion of contactable partners (44% vs 63% respectively, P = 0.017). MSM less commonly used provider referral than non-MSM (12% vs 53% respectively, P < 0.001) but more commonly used patient referral (41% MSM vs 9% non-MSM, P = 0.001). Of the 13 individuals found to be HIV-positive through contact tracing, nine (69%) were non-MSM.

Molecular analysis of human immunodeficiency virus strains associated with a case of criminal transmission of the virus.

An investigation was done of the evidence for transmission of human immunodeficiency virus (HIV) from an HIV-positive man to several male and female sex contacts. Phylogenetic analysis of sequences from the gag and env genes showed a close relationship between the predominant virus strains from the source and 2 contacts. However, the likelihood that a female contact was infected by the source could not be determined, despite contact tracing indicating that this may have occurred. One male, shown by contact tracing and molecular evidence to have been infected by the source, subsequently transmitted HIV to his female sex partner. HIV sequence from a plasma sample used as a control in the phylogenetic analysis contained env and gag sequences that were closely related to those from the source. An epidemiologic link between these 2 individuals was subsequently confirmed by contact tracing.

Basic fibroblast growth factor does not prevent heparan sulphate proteoglycan catabolism in intact cells, but it alters the distribution of the glycosaminoglycan degradation products.

Heparan sulphate proteoglycans on cell surfaces have been shown to mediate the degradation or recycling of several ligands. Since the interaction with ligand may affect proteoglycan catabolism once the complex is internalized, this could alter the cellular pool of heparan sulphate chains, with possible consequences for heparan sulphate-mediated cellular processes. We have recently demonstrated that the specific binding of basic fibroblast growth factor (bFGF) to heparan sulphate chains prevents the glycosaminoglycan from being degraded by partially purified heparanases from Chinese hamster ovary (CHO) cells [Tumova and Bame (1997) J. Biol. Chem. 272, 9078-9085]. The present study examines the effect of bFGF on heparan sulphate catabolism in intact cells. The distribution and size of the heparan sulphate degradation products in CHO cells was analysed in the presence and absence of bFGF using pulse-chase protocols. Although heparan sulphate molecules and bFGF are internalized through the same pathway, even relatively high concentrations of the growth factor do not have any inhibitory effects on glycosaminoglycan degradation. However, the interaction with the growth factor alters the distribution of heparan sulphate-degradation products, presumably by preventing secretion of the short heparanase-derived species. Our findings show that most of the free and bFGF-bound heparan sulphate chains are destined for lysosomes, which would be consistent with a recent hypothesis that the primary role of proteoglycan-mediated internalization of the growth factor is to remove bFGF from its site of action at the cell surface. However, in the presence of bFGF, a fraction of intracellular, heparanase-degraded heparan sulphate chains is delivered to the nucleus, suggesting that the glycosaminoglycan accompanies the growth factor to the organelle. It may be important for bFGF activity that the growth factor is protected from proteolytic degradation by its interaction with heparan sulphate. This work demonstrates that the internalization of a ligand along with the proteoglycan can affect the sorting of heparan sulphate-degradation products in endosomes, and the ultimate destination of the short glycosaminoglycan. It also provides evidence that formation of heparan sulphate-ligand complexes may regulate the recycling and degradation of both ligands and heparan sulphate chains and, consequently, affect their biological activities.

Complete genome sequence of Treponema pallidum, the syphilis spirochete.

The complete genome sequence of Treponema pallidum was determined and shown to be 1,138,006 base pairs containing 1041 predicted coding sequences (open reading frames). Systems for DNA replication, transcription, translation, and repair are intact, but catabolic and biosynthetic activities are minimized. The number of identifiable transporters is small, and no phosphoenolpyruvate:phosphotransferase carbohydrate transporters were found. Potential virulence factors include a family of 12 potential membrane proteins and several putative hemolysins. Comparison of the T. pallidum genome sequence with that of another pathogenic spirochete, Borrelia burgdorferi, the agent of Lyme disease, identified unique and common genes and substantiates the considerable diversity observed among pathogenic spirochetes.