362 research outputs found
TOA-based indoor localization and tracking with inaccurate floor plan map via MRMSC-PHD filter
This paper proposes a novel indoor localization scheme to jointly track a mobile device (MD) and update an inaccurate floor plan map using the time-of-arrival measured at multiple reference devices (RDs). By modeling the floor plan map as a collection of map features, the map and MD position can be jointly estimated via a multi-RD single-cluster probability hypothesis density (MSC-PHD) filter. Conventional MSC-PHD filters assume that each map feature generates at most one measurement for each RD. If single reflections of the detected signal are considered as measurements generated by map features, then higher-order reflections, which also carry information on the MD and map features, must be treated as clutter. The proposed scheme incorporates multiple reflections by treating them as virtual single reflections reflected from inaccurate map features and traces them to the corresponding virtual RDs (VRDs), referred to as a multi-reflection-incorporating MSC-PHD (MRMSC-PHD) filter. The complexity of using multiple reflection paths arises from the inaccuracy of the VRD location due to inaccuracy in the map features. Numerical results show that these multiple reflection paths can be modeled statistically as a Gaussian distribution. A computationally tractable implementation combining a new greedy partitioning scheme and a particle-Gaussian mixture filter is presented. A novel mapping error metric is then proposed to evaluate the estimated map's accuracy for plane surfaces. Simulation and experimental results show that our proposed MRMSC-PHD filter outperforms the existing MSC-PHD filters by up to 95% in terms of average localization and by up to 90% in terms of mapping accuracy
An Indoor Localization and Tracking System Using Successive Weighted RSS Projection
This letter proposes a novel successive weighted received signal strength (RSS) indoor localization and tracking system that projects previous time instance estimated mobile device (MD) position to provide projected RSS values. Such RSS projection increases the number of available RSS from Nm to Nm + N AP , where N AP is the total number of access points and Nm is the number of RSS values measured by MD, ranging from 0 to N AP . Our proposed system thus resolves the issues associated with insufficient or no RSS values received by MD. Inertial navigation system (INS) is merged with RSS localization system to provide a weighted fusion of projected and measured RSS values. The weighting factors are derived based on the INS and RSS localization accuracy where the former is initially accurate but deteriorates with time and the latter is time-independent but environment-dependent. The proposed system was tested in indoor environments and outperformed other existing localization systems such as RSS and INS fusion using extended Kalman filter and non-line-of-sight (NLOS) selection scheme, especially in heavy multipath environment, by 42% and 75%, respectively
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Replication and Meta-analysis of the Association between BDNF Val66Met Polymorphism and Cognitive Impairment in Patients Receiving Chemotherapy.
Cancer-related cognitive impairment (CRCI) adversely affects cancer patients. We had previously demonstrated that the BDNF Val66Met genetic polymorphism is associated with lower odds of subjective CRCI in the multitasking and verbal ability domains among breast cancer patients receiving chemotherapy. To further assess our previous findings, we evaluated the association of BDNF Val66Met polymorphism with subjective and objective CRCI in a temporally separate cohort of patients and pooled findings from both the original (n = 145) and current (n = 193) cohorts in a meta-analysis. Subjective CRCI was assessed using FACT-Cog. Objective CRCI was evaluated using computerized neuropsychological tests. Genotyping was carried out using Sanger sequencing. The association of BDNF Val66Met genotypes and CRCI was examined with logistic regression. A fixed-effect meta-analysis was conducted using the inverse variance method. In the meta-analysis (n = 338), significantly lower odds of CRCI were associated with Met allele carriers based on the global FACT-Cog score (OR = 0.52, 95% CI 0.29-0.94). Furthermore, Met allele carriers were at lower odds of developing impairment in the domains of memory (OR = 0.34, 95% CI: 0.17-0.70), multitasking (OR = 0.33, 95% CI: 0.18-0.59), and verbal ability (OR = 0.46, 95% CI: 0.24-0.88). Consistent with the previous study, lower odds of subjective CRCI among patients with the BDNF Met allele was observed after adjusting for potential confounders in the multitasking (OR = 0.30, 95% CI: 0.14-0.67) domain. In conclusion, carriers of the BDNF Met allele were protected against global subjective CRCI, particularly in the domains of memory, multitasking, and verbal ability. Our findings further contribute to the understanding of CRCI pathophysiology
Liver Transplantation in an Adult with Citrullinaemia Type 2
Citrullinaemia is a urea cycle defect that results from a deficiency of the enzyme arginosuccinate synthetase. Type 1 disease is diagnosed in childhood, whereas Type 2 disease is adult onset. We report the outcome of a patient with citrullinemia Type 2 who received a liver transplant at our center and the implications of this diagnosis in liver transplantation
Epidemiology and Prognosis of Paraneoplastic Syndromes in Hepatocellular Carcinoma
Background. Paraneoplastic syndromes (PNS) such as hypercalcaemia, hypercholesterolaemia, and erythrocytosis have been described in hepatocellular carcinoma (HCC). Aims. (1) To examine the prevalence, clinical characteristics, and survival of PNS in HCC patients and (2) to evaluate the extent to which each individual PNS impacts on patient survival. Methods. We prospectively evaluated the prevalence, clinical characteristics, and survival of PNS among 457 consecutive HCC patients seen in our department over a 10-year period and compared them with HCC patients without PNS. Results. PNS were present in 127 patients (27.8%). The prevalence of paraneoplastic hypercholesterolemia, hypercalcemia, and erythrocytosis 24.5%, 5.3%, and 3.9%, respectively. Patients with PNS had significantly higher alpha-fetoprotein levels, more advanced TNM stage, and shorter survival. Among the individual PNS, hypercalcemia and hypercholesterolemia were associated with more advanced disease and reduced survival but not erythrocytosis. On multivariate analysis, the presence of PNS was not found to be an independent prognostic factor for reduced HCC survival. Conclusion. PNS are not uncommon in HCC and are associated with poor prognosis and reduced survival due to their association with increased tumor burden. However, they do not independently predict poor survival. Individual PNS impact differently on HCC outcome; paraneoplastic hypercalcemia in particular is associated with poor outcome
First record of jellyfish Anomalorhiza shawi Light, 1921 (Cnidaria: Scyphozoa) and its associated organisms in Sabah, Malaysia
The present study describes a first record of the jellyfish Anomalorhiza shawi Light, 1921 from Malaysia. It belongs to the family Lychnorhizidae Haeckel, 1880, order Rhizostomeae Cuvier, 1799 (Cnidaria: Scyphozoa). The specimen was taken from Sepanggar Bay, Kota Kinabalu, off the Universiti Malaysia Sabah (UMS) Jetty by manual collection with a bucket. The size of the bell was 430 mm in diameter with oral arms measuring 290 mm in length including the brown terminal clubs, which differentiates A. shawi from other congeners of the family. Anomalorhiza shawi belongs to the monotypic genus Anomalorhiza, and was first reported from the Philippines, with later reports from Hawaii and Thailand. In addition, A. shawi was found associated with other organisms such as the silver shad, Alepes vari (Cuvier, 1833) (Carangidae), and the crab Charybdis feriata (Linnaeus, 1758) (Portunidae). The association between jellyfish and other organisms have been discussed here. A checklist is provided for the current species of scyphozoan jellyfish reported from Malaysia
Masquerading Hypervascular Exophytic Liver Nodule
Patients with liver cirrhosis are at increased risk of developing hepatocellular carcinoma (HCC) and are placed on routine surveillance for HCC. Diagnosis algorithms are in place to guide clinicians in the evaluation of liver lesions detected during surveillance. Radiological assessments are critical with diagnostic criteria based on identification of typical hallmarks of HCCs on multiphasic computed tomography (CT) and dynamic contrast-enhanced magnetic resonance imaging (MRI). We report a patient with a hypervascular exophytic lesion indeterminate for HCC on CT imaging. While the detection of an exophytic arterially-enhancing lesion in an at-risk patient on CT imaging may prompt clinicians to treat the lesion as HCC without further evaluation, the patient underwent contrast-enhanced MRI with the lesion being eventually diagnosed as an exophytic haemangioma. Thus, no further action was necessary and the patient was continued on routine HCC surveillance
Riverine sustainment 2012
Student Integrated ProjectIncludes supplementary materialThis technical report analyzed the Navy's proposed Riverine Force (RF) structure and capabilities for 2012. The Riverine Sustainment 2012 Team (RST) examined the cost and performance of systems of systems which increased RF sustainment in logistically barren environments. RF sustainment was decomposed into its functional areas of supply, repair, and force protection. The functional and physical architectures were developed in parallel and were used to construct an operational architecture for the RF. The RST used mathematical, agent-based and queuing models to analyze various supply, repair and force protection system alternatives. Extraction of modeling data revealed several key insights. Waterborne heavy lift connectors such as the LCU-2000 are vital in the re-supply of the RF when it is operating up river in a non-permissive environment. Airborne heavy lift connectors such as the MV-22 were ineffective and dominated by the waterborne variants in the same environment. Increase in manpower and facilities did appreciable add to the operational availability of the RF. Mean supply response time was the biggest factor effecting operational availability and should be kept below 24 hours to maintain operational availability rates above 80%. Current mortar defenses proposed by the RF are insufficient.N
First somatic mutation of E2F1 in a critical DNA binding residue discovered in well-differentiated papillary mesothelioma of the peritoneum
10.1186/gb-2011-12-9-r96Genome biology129R9
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