77 research outputs found
The Reality Of Survey Results; An Urban Goods Movement Case Study
Results from a commercial vehicle survey undertaken in Sydney, Australia show relative standard errors varying from 5% to 33%. When looking at similar survey data from around the world, very few explicitly state the accuracy of final results, which can be misleading to users. When errors are not quoted, many users assume the sampling error is so small it is not worthy of concern. However, in practical transport and traffic problems, there are very few situations where this is the case. In order to compare published results it is essential to know the sampling error so that conclusions can be drawn with confidence. This also enables scope for an evolving improvement in accuracy when variables with larger errors can be identified. Accuracy depends a lot on the survey methodology, response rate and rigour of the subsequent statistical analysis. And it also depends on the sample size and variability of the subject. This paper briefly describes the greater Sydney (Australia) commercial vehicle survey, it discusses the statistical analyses and highlights some important issues to consider in future surveys
Explaining Gender-Specific Racial Differences in Obesity Using Biased Self-Reports of Food Intake
Policymakers have an interest in identifying the differences in behavior patterns - namely, habitual caloric intake and physical activity levels - that contribute to demographic variation in body mass index (BMI) and obesity risk. While disparities in mean BMI and obesity rates between whites (non-Hispanic) and African-Americans (non-Hispanic) are well-documented, the behavioral differences that underlie these gaps have not been carefully identified. Moreover, the female-specificity of the black-white obesity gap has received relatively little attention. In the National Health and Nutrition Examination Surveys (NHANES) data, we initially observe a very weak relationship between self-reported measures of caloric intake and physical activity and either BMI or obesity risk, and these behaviors appear to explain only a small fraction of the black-white BMI gap (or obesity gap) among women. These unadjusted estimates echo previous findings from large survey datasets such as the NHANES. Using an innovative method to mitigate the widely recognized problem of measurement error in self-reported behaviors' proxying for measurement errors using the ratio of reported caloric intake to estimated true caloric needs' we obtain much stronger relationships between behaviors and BMI (or obesity risk). Behaviors can in fact account for a significant share of the BMI gap (and the obesity gap) between black women and white women and are consistent with the presence of much smaller gaps between black men and white men. The analysis also shows that the effects smoking has on BMI and obesity risk are small-to-negligible when measurement error is properly controlled
Multiple novel prostate cancer susceptibility signals identified by fine-mapping of known risk loci among Europeans
Genome-wide association studies (GWAS) have identified numerous common prostate cancer (PrCa) susceptibility loci. We have
fine-mapped 64 GWAS regions known at the conclusion of the iCOGS study using large-scale genotyping and imputation in
25 723 PrCa cases and 26 274 controls of European ancestry. We detected evidence for multiple independent signals at 16
regions, 12 of which contained additional newly identified significant associations. A single signal comprising a spectrum of
correlated variation was observed at 39 regions; 35 of which are now described by a novel more significantly associated lead SNP,
while the originally reported variant remained as the lead SNP only in 4 regions. We also confirmed two association signals in
Europeans that had been previously reported only in East-Asian GWAS. Based on statistical evidence and linkage disequilibrium
(LD) structure, we have curated and narrowed down the list of the most likely candidate causal variants for each region.
Functional annotation using data from ENCODE filtered for PrCa cell lines and eQTL analysis demonstrated significant
enrichment for overlap with bio-features within this set. By incorporating the novel risk variants identified here alongside the
refined data for existing association signals, we estimate that these loci now explain ∼38.9% of the familial relative risk of PrCa,
an 8.9% improvement over the previously reported GWAS tag SNPs. This suggests that a significant fraction of the heritability of
PrCa may have been hidden during the discovery phase of GWAS, in particular due to the presence of multiple independent
signals within the same regio
Acute Liver Injury Is Independent of B Cells or Immunoglobulin M
Acute liver injury is a clinically important pathology and results in the release of Danger Associated Molecular Patterns, which initiate an immune response. Withdrawal of the injurious agent and curtailing any pathogenic secondary immune response may allow spontaneous resolution of injury. The role B cells and Immunoglobulin M (IgM) play in acute liver injury is largely unknown and it was proposed that B cells and/or IgM would play a significant role in its pathogenesis.Tissue from 3 models of experimental liver injury (ischemia-reperfusion injury, concanavalin A hepatitis and paracetamol-induced liver injury) and patients transplanted following paracetamol overdose were stained for evidence of IgM deposition. Mice deficient in B cells (and IgM) were used to dissect out the role B cells and/or IgM played in the development or resolution of injury. Serum transfer into mice lacking IgM was used to establish the role IgM plays in injury.Significant deposition of IgM was seen in the explanted livers of patients transplanted following paracetamol overdose as well as in 3 experimental models of acute liver injury (ischemia-reperfusion injury, concanavalin A hepatitis and paracetamol-induced liver injury). Serum transfer into IgM-deficient mice failed to reconstitute injury (p = 0.66), despite successful engraftment of IgM. Mice deficient in both T and B cells (RAG1-/-) mice (p<0.001), but not B cell deficient (μMT) mice (p = 0.93), were significantly protected from injury. Further interrogation with T cell deficient (CD3εKO) mice confirmed that the T cell component is a key mediator of sterile liver injury. Mice deficient in B cells and IgM mice did not have a significant delay in resolution following acute liver injury.IgM deposition appears to be common feature of both human and murine sterile liver injury. However, neither IgM nor B cells, play a significant role in the development of or resolution from acute liver injury. T cells appear to be key mediators of injury. In conclusion, the therapeutic targeting of IgM or B cells (e.g. with Rituximab) would have limited benefit in protecting patients from acute liver injury
Vision, challenges and opportunities for a Plant Cell Atlas
With growing populations and pressing environmental problems, future economies will be increasingly plant-based. Now is the time to reimagine plant science as a critical component of fundamental science, agriculture, environmental stewardship, energy, technology and healthcare. This effort requires a conceptual and technological framework to identify and map all cell types, and to comprehensively annotate the localization and organization of molecules at cellular and tissue levels. This framework, called the Plant Cell Atlas (PCA), will be critical for understanding and engineering plant development, physiology and environmental responses. A workshop was convened to discuss the purpose and utility of such an initiative, resulting in a roadmap that acknowledges the current knowledge gaps and technical challenges, and underscores how the PCA initiative can help to overcome them.</jats:p
Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts
Designing a large-scale travel demand survey: New challenges and new opportunities
Information about travel demand, traveller behaviour and transport systems performance is an essential input to decision making on transport policy, planning and design issues. However, this information is difficult and expensive to collect and establish, so that its collection has been infrequent. Further, previous information technology and past methods for managing travel information have helped to make it expensive to access, maintain and keep current. This paper describes the findings of a research project called the Melbourne Travel Survey Research Projects (MTSRP), undertaken to determine the needs for and likely applications of new travel information for a large metropolitan area (Melbourne, Australia), and to define the desirable form for a new metropolitan travel demand survey program. The research required surveys of the present and anticipated needs for travel demand data and the available and required technology for data collection and information dissemination. The paper describes the findings of the research project, and provides an interpretation of their implications for a large-scale travel survey program.
INDs for PET molecular imaging probes-approach by an academic institution.
We have developed an efficient, streamlined, cost-effective approach to obtain Investigational New Drug (IND) approvals from the Food and Drug Administration (FDA) for positron emission tomography (PET) imaging probes (while the FDA uses the terminology PET drugs, we are using "PET imaging probes," "PET probes," or "probes" as the descriptive terms). The required application and supporting data for the INDs were collected in a collaborative effort involving appropriate scientific disciplines. This path to INDs was successfully used to translate three [(18) F]fluoro-arabinofuranosylcytosine (FAC) analog PET probes to phase 1 clinical trials. In doing this, a mechanism has been established to fulfill the FDA regulatory requirements for translating promising PET imaging probes from preclinical research into human clinical trials in an efficient and cost-effective manner
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