Overview of NWIS Software

The Nuclear Weapons Identification System (NWIS) is a system that performs radiation signature measurements on objects such as nuclear weapons components. NWIS consists of a {sup 252}Cf fission source, radiation detectors and associated analog electronics, data acquisition boards, and a computer running Windows NT and the application software. NWIS uses signal processing techniques to produce a radiation signature from the radiation emitted from the object. This signature can be stored and later compared to another signature to determine whether two objects are similar. A library of such signatures can be used to identify objects in closed containers as well as determine attributes such as fissile mass and in some cases enrichment. NWIS uses a {sup 252}Cf source on one side of the object to produce radiation that its detectors measure on the other side of the target (active mode). If the object naturally emits enough radiation, the {sup 252}Cf source is not required (passive mode). The NWIS data acquisition hardware has five detector channels. Each channel receives shaped detector pulses and times those pulses with 1 nanosecond resolution. In active mode measurements one of these channels receives pulses from a detector measuring the {sup 252}Cf source fissions. Thus, for active mode measurements, NWIS has the time of each {sup 252}Cf fission and the subsequent injection of neutrons and gamma rays into the object. The remaining channels receive pulses from the detectors measuring radiation from the object. These detectors record the amount and time of radiation exiting the object. By correlating the radiation events among the source and the other detectors, and among the detectors themselves, a characteristic response of the object to {sup 252}Cf radiation or its own internal radiation is measured. The data acquisition hardware consists of two custom-made boards. The Data Capture and Compression (DCC) board is built around a Gallium Arsine (GaAs) chip designed at ORNL. This chip assigns a time to each pulse received on the five detector channels and passes five compressed streams of time stamp data to the Data Acquisition (DA) board. The DA board performs additional data compression, consolidates the five data streams into one, formats the data, and passes it across the computer's PCI bus into computer memory. The computer processor performs the signal processing required to calculate the signatures and saves the result to disk. Signature analysis software provides the means to manipulate and match signatures in a signature library

Health behaviours and health literacy: Hepatitis B regarding Sub-Saharan African migrants living in Queensland

Introduction: Hepatitis B Virus (HBV) is becoming an increasing health burden worldwide. Previous research indicates that lack of HBV awareness is a key contributing factor regarding individuals not engaging in preventative health behaviours, nor seeking medical treatment. A particular target group whom have higher rates of HBV are people from Culturally and Linguistically Diverse (CALD) backgrounds; including migrants from Sub-Saharan African (SSA) countries which are known to have higher rates of HBV infection. This study identified gaps in health literacy and HBV knowledge, and investigated how these factors influence related health behaviours among SSA migrants in Queensland. Methods: Cultural workers from a community organisation recruited 187 SSA migrant participants via ‘awareness stalls’ in Queensland. Participants answered self-report surveys regarding HBV knowledge, health literacy and health-protective behaviours; utilising quantitative cross-sectional surveys. The research also replicated previous methodology and compared findings to previous studies conducted with other cultural groups. Results: Preliminary findings indicated HBV knowledge significantly mediated health literacy and HBV screening. Health literacy (regarding self-efficacy) significantly predicted health behaviours (HBV screening, vaccinations). Participants with higher education and participants aged under 40 years of age, reported higher health literacy and engaged in more health-protective behaviours. Conclusions: Preliminary findings indicate significant associations between health-protective behaviours, HBV knowledge and health literacy. Greater awareness of the relationships between these constructs may assist in creating more informed prevention and health promotion strategies for identified target communities to reduce health disparities

Seasonal variation and impact of waste-water lagoons as larval habitat on the population dynamics of Culicoides sonorensis (Diptera:Ceratpogonidae) at two dairy farms in northern California.

The Sacramento (northern Central) Valley of California (CA) has a hot Mediterranean climate and a diverse ecological landscape that is impacted extensively by human activities, which include the intensive farming of crops and livestock. Waste-water ponds, marshes, and irrigated fields associated with these agricultural activities provide abundant larval habitats for C. sonorensis midges, in addition to those sites that exist in the natural environment. Within this region, C. sonorensis is an important vector of bluetongue (BTV) and related viruses that adversely affect the international trade and movement of livestock, the economics of livestock production, and animal welfare. To characterize the seasonal dynamics of immature and adult C. sonorensis populations, abundance was monitored intensively on two dairy farms in the Sacramento Valley from August 2012- to July 2013. Adults were sampled every two weeks for 52 weeks by trapping (CDC style traps without light and baited with dry-ice) along N-S and E-W transects on each farm. One farm had large operational waste-water lagoons, whereas the lagoon on the other farm was drained and remained dry during the study. Spring emergence and seasonal abundance of adult C. sonorensis on both farms coincided with rising vernal temperature. Paradoxically, the abundance of midges on the farm without a functioning waste-water lagoon was increased as compared to abundance on the farm with a waste-water lagoon system, indicating that this infrastructure may not serve as the sole, or even the primary larval habitat. Adult midges disappeared from both farms from late November until May; however, low numbers of parous female midges were detected in traps set during daylight in the inter-seasonal winter period. This latter finding is especially critical as it provides a potential mechanism for the "overwintering" of BTV in temperate regions such as northern CA. Precise documentation of temporal changes in the annual abundance and dispersal of Culicoides midges is essential for the creation of models to predict BTV infection of livestock and to develop sound abatement strategies

Overview of NWIS software

The Nuclear Weapons Identification System (NWIS) is a system that performs radiation signature measurements on objects such as nuclear weapons components. NWIS consists of a {sup 252} Cf fission source, radiation detectors and associated analog electronics, data acquisition boards, and computer running Windows NT and the application software. NWIS uses signal processing techniques to produced a radiation signature from the radiation emitted from the object. The signature can be stored and later compared to another signature to determine whether two objects are similar. A library of such signatures can be used to identify objects in closed containers as well as determine such attributes as fissile mass and it some cases enrichment. There are three executables built from the software: (1) Windows NT kernel-mode device driver; (2) data acquisition application; and (3) data analysis application. The device driver is the interface between the NWIS data acquisition boards and the remainder o f the software. The data acquisition executable is the user's tool for making an NWIS measurement; it has limited data display abilities. The data analysis executable is a user's tool for displaying an NWIS measurement, including matching it to other NWIS measurements. A users manual for the software is included

Measurement of transient two-phase flow velocity using statistical signal analysis of impedance probe signals

A computational algorithm has been developed to measure transient, phase-interface velocity in two-phase, steam-water systems. The algorithm will be used to measure the transient velocity of steam-water mixture during simulated PWR reflood experiments. By utilizing signals produced by two, spatially separated impedance probes immersed in a two-phase mixture, the algorithm computes the average transit time of mixture fluctuations moving between the two probes. This transit time is computed by first, measuring the phase shift between the two probe signals after transformation to the frequency domain and then computing the phase shift slope by a weighted least-squares fitting technique. Our algorithm, which has been tested with both simulated and real data, is able to accurately track velocity transients as fast as 4 m/s/s

Sulfur analysis of Bolu-Mengen lignite before and after microbiological treatment using reductive pyrolysis and gas chromatography/mass spectrometry

Atmospheric pressure-temperature programmed reduction coupled with on-line mass spectrometry (AP-TPR/MS) is used for the first time on microbiologically treated coal samples as a technique to monitor the degree of desulfurization of the various sulfur functionalities. The experimental procedure enables the identification of both organic and inorganic sulfur species present in the coal matrix. A better insight in the degradation of the coal matrix and the accompanying processes during the AP-TPR experiment is obtained by a quantitative differentiation of the sulfur. The determination of the sulfur balance for the reductive pyrolysis gives an overview of the side reactions and their relative contribution in the total process. The volatile sulfur species are unambiguously identified using AP-TPR off-line coupled with gas chromatography/mass spectrometry (GC/MS). In this way, fundamental mechanisms and reactions that occur during the reductive pyrolysis could be quantified, explaining the differences in AP-TPR recoveries. Therefore, this study gives a clearer view on the possibilities and limitations of AP-TPR as a technique to monitor sulfur functionalities in coal

Titanium hardware extrusion following pediatric cranioplasty

Aging pediatric cranioplasty patients with titanium implants are a population at risk for scalp breakdown and implant extrusion. Complications from titanium use in adult cranioplasty patients are well documented in the medical literature. Reports of complications focused on pediatric populations are sparse. In this case series, we report two examples of negative sequelae associated with titanium utilization in infant cranioplasty and discuss our treatment strategy for each case

HIV-Related Knowledge and Practices among Asian and African Migrants Living in Australia: Results from a Cross-Sectional Survey and Qualitative Study

Australian HIV notification rates are higher for people born in Northeast Asia, Southeast Asia and sub-Saharan Africa compared to Australian-born people. The Migrant Blood-Borne Virus and Sexual Health Survey represents the first attempt to build the national evidence base regarding HIV knowledge, risk behaviors and testing among migrants in Australia. To inform survey development, preliminary qualitative research was conducted with a convenience sample of n = 23 migrants. A survey was developed with reference to the qualitative data and existing survey instruments. Non-probability sampling of adults born in Northeast Asia, Southeast Asia and sub-Saharan Africa was undertaken (n = 1489), and descriptive and bivariate analyses of data were conducted. Knowledge of pre-exposure prophylaxis was low (15.59%), and condom use at last sexual encounter was reported by 56.63% of respondents engaging in casual sex, and 51.80% of respondents reported multiple sexual partners. Less than one-third (31.33%) of respondents reported testing for any sexually transmitted infection or blood-borne virus in the previous two years and, of these, less than half (45.95%) tested for HIV. Confusion surrounding HIV testing practices was reported. These findings identify policy interventions and service improvements critically needed to reduce widening disparities regarding HIV in Australia

Towards a resource-based habitat approach for spatial modelling of vector-borne disease risks

Given the veterinary and public health impact of vector-borne diseases, there is a clear need to assess the suitability of landscapes for the emergence and spread of these diseases. Current approaches for predicting disease risks neglect key features of the landscape as components of the functional habitat of vectors or hosts, and hence of the pathogen. Empirical–statistical methods do not explicitly incorporate biological mechanisms, whereas current mechanistic models are rarely spatially explicit; both methods ignore the way animals use the landscape (i.e. movement ecology). We argue that applying a functional concept for habitat, i.e. the resource-based habitat concept (RBHC), can solve these issues. The RBHC offers a framework to identify systematically the different ecological resources that are necessary for the completion of the transmission cycle and to relate these resources to (combinations of) landscape features and other environmental factors. The potential of the RBHC as a framework for identifying suitable habitats for vector-borne pathogens is explored and illustrated with the case of bluetongue virus, a midge-transmitted virus affecting ruminants. The concept facilitates the study of functional habitats of the interacting species (vectors as well as hosts) and provides new insight into spatial and temporal variation in transmission opportunities and exposure that ultimately determine disease risks. It may help to identify knowledge gaps and control options arising from changes in the spatial configuration of key resources across the landscape. The RBHC framework may act as a bridge between existing mechanistic and statistical modelling approaches