1,098 research outputs found
Covariant polarized radiative transfer on cosmological scales for investigating large-scale magnetic field structures
Polarization of radiation is a powerful tool to study cosmic magnetism and
analysis of polarization can be used as a diagnostic tool for large-scale
structures. In this paper, we present a solid theoretical foundation for using
polarized light to investigate large-scale magnetic field structures: the
cosmological polarized radiative transfer (CPRT) formulation. The CPRT
formulation is fully covariant. It accounts for cosmological and relativistic
effects in a self-consistent manner and explicitly treats Faraday rotation, as
well as Faraday conversion, emission, and absorption processes. The formulation
is derived from the first principles of conservation of phase-space volume and
photon number. Without loss of generality, we consider a flat
Friedmann-Robertson-Walker (FRW) space-time metric and construct the
corresponding polarized radiative transfer equations. We propose an all-sky
CPRT calculation algorithm, based on a ray-tracing method, which allows
cosmological simulation results to be incorporated and, thereby, model
templates of polarization maps to be constructed. Such maps will be crucial in
our interpretation of polarized data, such as those to be collected by the
Square Kilometer Array (SKA). We describe several tests which are used for
verifying the code and demonstrate applications in the study of the
polarization signatures in different distributions of electron number density
and magnetic fields. We present a pencil-beam CPRT calculation and an all-sky
calculation, using a simulated galaxy cluster or a model magnetized universe
obtained from GCMHD+ simulations as the respective input structures. The
implications on large-scale magnetic field studies are discussed; remarks on
the standard methods using rotation measure are highlighted.Comment: 32 pages, 14 figure
Effects of an Advocacy Trial on Food Industry Salt Reduction EffortsâAn Interim Process Evaluation
The decisions made by food companies are a potent factor shaping the nutritional quality of the food supply. A number of non-governmental organizations (NGOs) advocate for corporate action to reduce salt levels in foods, but few data define the effectiveness of advocacy. This present report describes the process evaluation of an advocacy intervention delivered by one Australian NGO directly to food companies to reduce the salt content of processed foods. Food companies were randomly assigned to intervention (n = 22) or control (n = 23) groups. Intervention group companies were exposed to pre-planned and opportunistic communications, and control companies to background activities. Seven pre-defined interim outcome measures provided an indication of the effect of the intervention and were assessed using intention-to-treat analysis. These were supplemented by qualitative data from nine semi-structured interviews. The mean number of public communications supporting healthy food made by intervention companies was 1.5 versus 1.8 for control companies (p = 0.63). Other outcomes, including the mean number of news articles, comments and reports (1.2 vs. 1.4; p = 0.72), a published nutrition policy (23% vs. 44%; p = 0.21), public commitment to the Australian governmentâs Food and Health Dialogue (FHD) (41% vs. 61%; p = 0.24), evidence of a salt reduction plan (23% vs. 30%; p = 0.56), and mean number of communications with the NGO (15 vs. 11; p = 0.28) were also not significantly different. Qualitative data indicated the advocacy trial had little effect. The absence of detectable effects of the advocacy intervention on the interim markers indicates there may be no impact of the NGO advocacy trial on the primary outcome of salt reduction in processed foods
Epigenetic regulation of corneal epithelial differentiation by TET2
Epigenetic DNA modification by 5-hydroxymethylcytosine (5hmC), generated by the Ten-eleven translocation (TET) dioxygenases, regulates diverse biological functions in many organ tissues, including the mammalian eye. For example, 5hmC has been shown to be involved in epigenetic regulation of retinal gene expression. However, a functional role of 5hmC in corneal differentiation has not been investigated to date. Here, we examined 5hmC and TET function in the human cornea. We found 5hmC highly expressed in MUC16-positive terminally differentiated cells that also co-expressed the 5hmC-generating enzyme TET2. TET2 knockdown (KD) in cultured corneal epithelial cells led to significant reductions of 5hmC peak distributions and resulted in transcriptional repression of molecular pathways involved in corneal differentiation, as evidenced by downregulation of MUC4, MUC16, and Keratin 12. Additionally, integrated TET2 KD RNA-seq and genome-wide Reduced Representation Hydroxymethylation Profiling revealed novel epigenetically regulated genes expressed by terminally differentiated cells, including KRT78, MYEOV, and MAL. In aggregate, our findings reveal a novel function of TET2 in the epigenetic regulation of corneal epithelial gene expression and identify novel TET2-controlled genes expressed in differentiated corneal epithelial cells. These results point to potential roles for TET2 induction strategies to enhance treatment of corneal diseases associated with abnormal epithelial maturation
Sodium content in processed food items in Sweden compared to other countries: a cross-sectional multinational study
BackgroundDietary sodium has a dose-response relationship with cardiovascular disease, and sodium intake in Sweden exceeds national and international recommendations. Two thirds of dietary sodium intake comes from processed foods, and adults in Sweden eat more processed foods than any other European country. We hypothesized that sodium content in processed foods is higher in Sweden than in other countries. The aim of this study was to investigate sodium content in processed food items in Sweden, and how it differs from Australia, France, Hong Kong, South Africa, the United Kingdom and the United States.MethodsData were collected from retailers by trained research staff using standardized methods. Data were categorized into 10 food categories and compared using Kruskal-Wallis test of ranks. Sodium content in the food items was compared in mg sodium per 100 g of product, based on the nutritional content labels on the packages.ResultsCompared to other countries, Sweden had among the highest sodium content in the âdairyâ and âconvenience foodsâ categories, but among the lowest in âcereal and grain products,â âseafood and seafood productsâ and âsnack foodsâ categories. Australia had the overall lowest sodium content, and the US the overall highest. The highest sodium content in most analyzed countries was found in the âmeat and meat productsâ category. The highest median sodium content in any category was found among âsauces, dips, spreads and dressingsâ in Hong Kong.ConclusionThe sodium content differed substantially between countries in all food categories, although contrary to our hypothesis, processed foods overall had lower sodium content in Sweden than in most other included countries. Sodium content in processed food was nonetheless high also in Sweden, and especially so in increasingly consumed food categories, such as âconvenience foodsâ
Circulating and Dietary Omegaâ3 and Omegaâ6 Polyunsaturated Fatty Acids and Incidence of CVD in the MultiâEthnic Study of Atherosclerosis
Background: Dietary guidelines support intake of polyunsaturated fatty acids (PUFAs) in fish and vegetable oils. However, some controversy remains about benefits of PUFAs, and most prior studies have relied on selfâreported dietary assessment in relatively homogeneous populations. Methods and Results: In a multiethnic cohort of 2837 US adults (whites, Hispanics, African Americans, Chinese Americans), plasma phospholipid PUFAs were measured at baseline (2000â2002) using gas chromatography and dietary PUFAs estimated using a food frequency questionnaire. Incident cardiovascular disease (CVD) events (including coronary heart disease and stroke; n=189) were prospectively identified through 2010 during 19 778 personâyears of followâup. In multivariableâadjusted Cox models, circulating nâ3 eicosapentaenoic acid and docosahexaenoic acid were inversely associated with incident CVD, with extremeâquartile hazard ratios (95% CIs) of 0.49 for eicosapentaenoic acid (0.30 to 0.79; Ptrend=0.01) and 0.39 for docosahexaenoic acid (0.22 to 0.67; Ptrend<0.001). nâ3 Docosapentaenoic acid (DPA) was inversely associated with CVD in whites and Chinese, but not in other race/ethnicities (Pâinteraction=0.01). No significant associations with CVD were observed for circulating nâ3 alphaâlinolenic acid or nâ6 PUFA (linoleic acid, arachidonic acid). Associations with CVD of selfâreported dietary PUFA were consistent with those of the PUFA biomarkers. All associations were similar across racialâethnic groups, except those of docosapentaenoic acid. Conclusions: Both dietary and circulating eicosapentaenoic acid and docosahexaenoic acid, but not alphaâlinolenic acid or nâ6 PUFA, were inversely associated with CVD incidence. These findings suggest that increased consumption of nâ3 PUFA from seafood may prevent CVD development in a multiethnic population
Molecular Diagnostics and Pathology of Major Brain Tumors
Tumors of central nervous system (CNS) account for a small portion of tumors of human body, which include tumors occurring in the parenchyma of brain and spinal cord as well as their coverings. The following chapter covers some new development in some major brain tumors in both pediatric and adult populations, as well as some uncommon but diagnostic and management challenging tumors
Sodium content in processed food items in Sweden compared to other countries: a cross-sectional multinational study
Background Dietary sodium has a dose-response relationship with cardiovascular disease, and sodium intake in Sweden exceeds national and international recommendations. Two thirds of dietary sodium intake comes from processed foods, and adults in Sweden eat more processed foods than any other European country. We hypothesized that sodium content in processed foods is higher in Sweden than in other countries. The aim of this study was to investigate sodium content in processed food items in Sweden, and how it differs from Australia, France, Hong Kong, South Africa, the United Kingdom and the United States. Methods Data were collected from retailers by trained research staff using standardized methods. Data were categorized into 10 food categories and compared using Kruskal-Wallis test of ranks. Sodium content in the food items was compared in mg sodium per 100 g of product, based on the nutritional content labels on the packages. Results Compared to other countries, Sweden had among the highest sodium content in the âdairyâ and âconvenience foodsâ categories, but among the lowest in âcereal and grain products,â âseafood and seafood productsâ and âsnack foodsâ categories. Australia had the overall lowest sodium content, and the US the overall highest. The highest sodium content in most analyzed countries was found in the âmeat and meat productsâ category. The highest median sodium content in any category was found among âsauces, dips, spreads and dressingsâ in Hong Kong. Conclusion The sodium content differed substantially between countries in all food categories, although contrary to our hypothesis, processed foods overall had lower sodium content in Sweden than in most other included countries. Sodium content in processed food was nonetheless high also in Sweden, and especially so in increasingly consumed food categories, such as âconvenience foodsâ
Contribution of trans-fatty acid intake to coronary heart disease burden in Australia: a modelling study
Trans-fatty acids (TFAs) intake has been consistently associated with a higher risk of coronary heart disease (CHD) mortality. We provided an updated assessment of TFA intake in Australian adults in 2010 and conducted modeling to estimate CHD mortality attributable to TFA intake. Data of the 2011–2012 National Nutrition and Physical Activity Survey was used to assess TFA intake. The CHD burden attributable to TFA was calculated by comparing the current level of TFA intake to a counterfactual setting where consumption was lowered to a theoretical minimum distribution of 0.5% energy. The average TFA intake among adults was 0.59% energy, and overall 10% of adults exceeded the World Health Organization (WHO) recommended limit of 1% energy. Education and income were moderately and inversely associated with TFA intake (p-value ≤ 0.001), with one in seven adults in the lowest income and education quintile having >1% energy from TFA. Australia had 487 CHD deaths (95% uncertainty interval, 367–615) due to TFA exposure, equivalent to 1.52% (95% uncertainty limits: 1.15%–1.92%) of all CHD mortality. The relative impact of TFA exposure on CHD mortality in Australia is limited, but, in absolute terms, still substantial. Policies aimed at reducing industrial TFA exposure can reduce socioeconomic inequalities in health and may therefore be desirable
Transcript-indexed ATAC-seq for precision immune profiling.
T cells create vast amounts of diversity in the genes that encode their T cell receptors (TCRs), which enables individual clones to recognize specific peptide-major histocompatibility complex (MHC) ligands. Here we combined sequencing of the TCR-encoding genes with assay for transposase-accessible chromatin with sequencing (ATAC-seq) analysis at the single-cell level to provide information on the TCR specificity and epigenomic state of individual T cells. By using this approach, termed transcript-indexed ATAC-seq (T-ATAC-seq), we identified epigenomic signatures in immortalized leukemic T cells, primary human T cells from healthy volunteers and primary leukemic T cells from patient samples. In peripheral blood CD4+ T cells from healthy individuals, we identified cis and trans regulators of naive and memory T cell states and found substantial heterogeneity in surface-marker-defined T cell populations. In patients with a leukemic form of cutaneous T cell lymphoma, T-ATAC-seq enabled identification of leukemic and nonleukemic regulatory pathways in T cells from the same individual by allowing separation of the signals that arose from the malignant clone from the background T cell noise. Thus, T-ATAC-seq is a new tool that enables analysis of epigenomic landscapes in clonal T cells and should be valuable for studies of T cell malignancy, immunity and immunotherapy
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