Multi-Tag Access for a High Precision Ultra-Wideband Localization System

Ultra-Wideband (UWB) wireless positioning systems have many advantages for track- ing and locating items in indoor environments. Surgical navigation and industrial process control are potential applications for high accuracy UWB localization systems with millimeter or sub-millimeter accuracy. I present improvements made to an existing high accuracy, multi-tag, UWB localization system. The goal of this thesis was to improve the multi-tag performance of this system while maintaining the high localization accuracy, and to utilize the UWB system for digital communications allowing the existing narrowband 2.4 GHz transceiver to be eliminated. This thesis presents a proof-of-concept for a multi-tag, UWB localization system utilizing orthogonal time hopping multiple access (OTHMA). Asynchronous transmit- only UWB digital communication allows identification of tags without the use of a narrowband control channel, and time di↵erence of arrival (TDOA) accomplishes localization. A digital sampling circuit is used for both localization and digital communication. I address the inherent challenge of collisions in an asynchronous transmit-only system while maintaining high accuracy and high update rates. An experimental system was developed consisting of two base stations and two tags allowing measurement of 1-D localization accuracy along with system update rates. The experimental results for localization accuracy were equivalent to results from the existing system while update rates were improved by greater than 50%

An approach to hydrogeological modeling of a large system of groundwater-fed lakes and wetlands in the Nebraska Sand Hills, USA

The feasibility of a hydrogeological modeling approach to simulate several thousand shallow groundwater-fed lakes and wetlands without explicitly considering their connection with groundwater is investigated at the regional scale (~40,000 km2) through an application in the semi-arid Nebraska Sand Hills (NSH), USA. Hydraulic heads are compared to local land-surface elevations from a digital elevation model (DEM) within a geographic information system to assess locations of lakes and wetlands. The water bodies are inferred where hydraulic heads exceed, or are above a certain depth below, the land surface. Numbers of lakes and/or wetlands are determined via image cluster analysis applied to the same 30-m grid as the DEM after interpolating both simulated and estimated heads. The regional water-table map was used for groundwater model calibration, considering MODIS-based net groundwater recharge data. Resulting values of simulated total baseflow to interior streams are within 1% of observed values. Locations, areas, and numbers of simulated lakes and wetlands are compared with Landsat 2005 survey data and with areas of lakes from a 1979–1980 Landsat survey and the National Hydrography Dataset. This simplified process-based modeling approach avoids the need for field-based morphology or water-budget data from individual lakes or wetlands, or determination of lake-groundwater exchanges, yet it reproduces observed lake-wetland characteristics at regional groundwater management scales. A better understanding of the NSH hydrogeology is attained, and the approach shows promise for use in simulations of groundwater-fed lake and wetland characteristics in other large groundwater systems. Includes supplementary materials

Structures on a K3 surface

In the first part of this paper, we examine properties of K3 surfaces of the form: (x2 + 1)(y2 + 1)(z2 + 1) + Axyz − 2 = 0 We show the surface has Picard number q 12 by finding 12 curves whose equivalence classes are linearly independent. These curves have self intersection −2. We find the lattice representations of the single-coordinate swapping automorphisms in x, y, and z. We show that we have enough of the Lattice to make accurate predictions of polynomial degree growth under the automorphisms. We describe these automorphisms in terms of operations on elliptic curves. In the second part of this paper, we look at curves whose shape is sketched by the orbit of a point under the composed automorphisms mentioned above. These curves were studied by Fields Medalist Kurt McMullen. One can prove these curves are non-algebraic through the use of intersection theory. We offer a simple counting argument that one such curve is not algebraic. We do this by counting points in Fp and comparing this to the Hasse-Weil upper bound for such curves

Influence of biological variations and sample handling on measured microalbuminuria in diabetic patients

Five immunochemical assays for determining low concentrations of albumin were investigated. These were a radioimmunoassay (RIA); turbidimetric immunoassays (TIA) both according to end-point measuring principle on a Cobas Fara and Hitachi 717 analysers, and according to kinetic measuring principle on a Turbitimer instrument; and a nephelometric immunoassay (NIA). All achieved the analytical goal necessary for optimal patient care. The correlations between the albumin concentrations measured with the different techniques were very good. In vitro glycation of albumin did not influence albumin concentrations measured by the five assays. Urine albumin excretion measured over 3 consecutie days showed considerable day-to-day variation. This was highest for spot-urine specimens and significantly lower for 24 h and timed-overnight samples. Variation of storage temperature (room temperature, 4°C, -20°C), time (up till 3 months), and pH (within the range pH 5-8) of the urine samples did not change significantly the measured albumin concentrations. Different sample preparations (vortex-mixing, centrifugation, and thawing) had no influence on the measured albumin concentration. In conclusion, a maximum standardization of the collection of timed-overnight urine samples for screening and 24 h urine sampels for confirmation of microalbuminuria during 3 consecutive days is more crucial than the choice of the immunological technique

UC-15 Malware Analysis Using Reverse Engineering

The motivation for this project is driven by evaluation of the different tools on the market that allow for breaking down executables or binary files, and understanding what the malware is doing. By reverse-engineering the malware, we can understand its impact and how to protect against it. Our focus is to understand where different tools are stronger than others, as well as understand the evolving landscape of malware and security overall. For this capstone project, we utilized two different tools and many sample malware files. The methods used to debug the malware are detailed in our milestone two report and will be expanded upon in our final presentation. At this point, we\u27ve found the tool WinDbg to be the most versatile for binary and executable debugging. We also evaluated IDA Pro, and understand the many ways in which its graphical display of data and relationships, equips a researcher with the necessary tools and information to walk through an executable. Our focus in milestone 3 is to expand our documentation and guide on malware debugging to the point that it provides a user the full breadth of information and steps needed to start from scratch and end with a broken apart piece of malware. We provided much of this as part of the milestone 2 presentation and report, but we will continue to build on it so it\u27s a useful how-to guide for anyone trying to debug a piece of malicious code.Advisors(s): Dr. Ying Xie [email protected](s): SecurityIT 498

Advice on healthy eating and physical activity where it is needed most : empowering home-visiting human services to provide the right information at the right time to vulnerable families

Background: Excessive weight gain adversely impacts on the health, social and economic wellbeing of children and families. The aim of this pilot study was to assess the feasibility of a practice change intervention to improve the physical activity and healthy eating support offered by staff of human service organisations during home visits. Methods: The study employed a pre-post design. Sixty nine support staff and 29 managers from human service organisations from the Hunter New England Area Health Service (HNEAHS) region of NSW participated in the trial. Research officers provided staff with healthy eating and physical activity training, telephone support and resources, and encouraged managers to adopt a healthy eating and physical activity policy, and to support their staff in providing healthy eating and physical activity guidance to families. Results: Compared to pre-intervention, support staff of human service organisations were more likely to provide healthy eating and physical activity support to client families. The intervention was found to be acceptable to staff and managers. Conclusion: The findings of this study suggest that a variety of supportive, practice change initiatives may be a feasible approach to increasing obesity prevention support provided to disadvantaged families by human service organisation staff

Viewpoint: Evaluating the impact of malaria control efforts on mortality in sub-Saharan Africa

OBJECTIVE To describe an approach for evaluating the impact of malaria control efforts on malaria-associated mortality in sub-Saharan Africa, where disease-specific mortality trends usually cannot be measured directly and most malaria deaths occur among young children. METHODS Methods for evaluating changes in malaria-associated mortality are examined; advantages and disadvantages are presented. RESULTS All methods require a plausibility argument - i.e., an assumption that mortality reductions can be attributed to programmatic efforts if improvements are found in steps of the causal pathway between intervention scale-up and mortality trends. As different methods provide complementary information, they can be used together. We recommend following trends in the coverage of malaria control interventions, other factors influencing childhood mortality, malaria-associated morbidity (especially anaemia), and all-cause childhood mortality. This approach reflects decreases in malaria's direct and indirect mortality burden and can be examined in nearly all countries. Adding other information can strengthen the plausibility argument: trends in indicators of malaria transmission, information from demographic surveillance systems and sentinel sites where malaria diagnostics are systematically used, and verbal autopsies linked to representative household surveys. Health facility data on malaria deaths have well-recognized limitations; however, in specific circumstances, they could produce reliable trends. Model-based predictions can help describe changes in malaria-specific burden and assist with program management and advocacy. CONCLUSIONS Despite challenges, efforts to reduce malaria-associated mortality in Africa can be evaluated with trends in malaria intervention coverage and all-cause childhood mortality. Where there are resources and interest, complementary data on malaria morbidity and malaria-specific mortality could be added

Quality of malaria case management at outpatient health facilities in Angola

<p>Abstract</p> <p>Background</p> <p>Angola's malaria case-management policy recommends treatment with artemether-lumefantrine (AL). In 2006, AL implementation began in Huambo Province, which involved training health workers (HWs), supervision, delivering AL to health facilities, and improving malaria testing with microscopy and rapid diagnostic tests (RDTs). Implementation was complicated by a policy that was sometimes ambiguous.</p> <p>Methods</p> <p>Fourteen months after implementation began, a cross-sectional survey was conducted in 33 outpatient facilities in Huambo Province to assess their readiness to manage malaria and the quality of malaria case-management for patients of all ages. Consultations were observed, patients were interviewed and re-examined, and HWs were interviewed.</p> <p>Results</p> <p>Ninety-three HWs and 177 consultations were evaluated, although many sampled consultations were missed. All facilities had AL in-stock and at least one HW trained to use AL and RDTs. However, anti-malarial stock-outs in the previous three months were common, clinical supervision was infrequent, and HWs had important knowledge gaps. Except for fever history, clinical assessments were often incomplete. Although testing was recommended for all patients with suspected malaria, only 30.7% of such patients were tested. Correct testing was significantly associated with caseloads < 25 patients/day (odds ratio: 18.4; p < 0.0001) and elevated patient temperature (odds ratio: 2.5 per 1°C increase; p = 0.007). Testing was more common among AL-trained HWs, but the association was borderline significant (p = 0.072). When the malaria test was negative, HWs often diagnosed patients with malaria (57.8%) and prescribed anti-malarials (60.0%). Sixty-six percent of malaria-related diagnoses were correct, 20.1% were minor errors, and 13.9% were major (potentially life-threatening) errors. Only 49.0% of malaria treatments were correct, 5.4% were minor errors, and 45.6% were major errors. HWs almost always dosed AL correctly and gave accurate dosing instructions to patients; however, other aspects of counseling needed improvement.</p> <p>Conclusion</p> <p>By late-2007, substantial progress had been made to implement the malaria case-management policy in a setting with weak infrastructure. However, policy ambiguities, under-use of malaria testing, and distrust of negative test results led to many incorrect malaria diagnoses and treatments. In 2009, Angola published a policy that clarified many issues. As problems identified in this survey are not unique to Angola, better strategies for improving HW performance are urgently needed.</p

Managing uncertainty in movement knowledge for environmental decisions.

Species' movements affect their response to environmental change but movement knowledge is often highly uncertain. We now have well-established methods to integrate movement knowledge into conservation practice but still lack a framework to deal with uncertainty in movement knowledge for environmental decisions. We provide a framework that distinguishes two dimensions of species' movement that are heavily influenced by uncertainty: knowledge about movement and relevance of movement to environmental decisions. Management decisions can be informed by their position in this knowledge-relevance space. We then outline a framework to support decisions around (1) increasing understanding of the relevance of movement knowledge, (2) increasing robustness of decisions to uncertainties and (3) improving knowledge on species' movement. Our decision-support framework provides guidance for managing movement-related uncertainty in systematic conservation planning, agri-environment schemes, habitat restoration and international biodiversity policy. It caters to different resource levels (time and funding) so that species' movement knowledge can be more effectively integrated into environmental decisions

Stage-Specific Inhibition of MHC Class I Presentation by the Epstein-Barr Virus BNLF2a Protein during Virus Lytic Cycle

gamma-herpesvirus Epstein-Barr virus (EBV) persists for life in infected individuals despite the presence of a strong immune response. During the lytic cycle of EBV many viral proteins are expressed, potentially allowing virally infected cells to be recognized and eliminated by CD8+ T cells. We have recently identified an immune evasion protein encoded by EBV, BNLF2a, which is expressed in early phase lytic replication and inhibits peptide- and ATP-binding functions of the transporter associated with antigen processing. Ectopic expression of BNLF2a causes decreased surface MHC class I expression and inhibits the presentation of indicator antigens to CD8+ T cells. Here we sought to examine the influence of BNLF2a when expressed naturally during EBV lytic replication. We generated a BNLF2a-deleted recombinant EBV (ΔBNLF2a) and compared the ability of ΔBNLF2a and wild-type EBV-transformed B cell lines to be recognized by CD8+ T cell clones specific for EBV-encoded immediate early, early and late lytic antigens. Epitopes derived from immediate early and early expressed proteins were better recognized when presented by ΔBNLF2a transformed cells compared to wild-type virus transformants. However, recognition of late antigens by CD8+ T cells remained equally poor when presented by both wild-type and ΔBNLF2a cell targets. Analysis of BNLF2a and target protein expression kinetics showed that although BNLF2a is expressed during early phase replication, it is expressed at a time when there is an upregulation of immediate early proteins and initiation of early protein synthesis. Interestingly, BNLF2a protein expression was found to be lost by late lytic cycle yet ΔBNLF2a-transformed cells in late stage replication downregulated surface MHC class I to a similar extent as wild-type EBV-transformed cells. These data show that BNLF2a-mediated expression is stage-specific, affecting presentation of immediate early and early proteins, and that other evasion mechanisms operate later in the lytic cycle