209 research outputs found
Random line tessellations of the plane: statistical properties of many-sided cells
We consider a family of random line tessellations of the Euclidean plane
introduced in a much more formal context by Hug and Schneider [Geom. Funct.
Anal. 17, 156 (2007)] and described by a parameter \alpha\geq 1. For \alpha=1
the zero-cell (that is, the cell containing the origin) coincides with the
Crofton cell of a Poisson line tessellation, and for \alpha=2 it coincides with
the typical Poisson-Voronoi cell. Let p_n(\alpha) be the probability for the
zero-cell to have n sides. By the methods of statistical mechanics we construct
the asymptotic expansion of \log p_n(\alpha) up to terms that vanish as
n\to\infty. In the large-n limit the cell is shown to become circular. The
circle is centered at the origin when \alpha>1, but gets delocalized for the
Crofton cell, \alpha=1, which is a singular point of the parameter range. The
large-n expansion of \log p_n(1) is therefore different from that of the
general case and we show how to carry it out. As a corollary we obtain the
analogous expansion for the {\it typical} n-sided cell of a Poisson line
tessellation.Comment: 26 pages, 3 figure
Types and Amounts of Nonnutritive Sweeteners Purchased by US Households: A Comparison of 2002 and 2018 Nielsen Homescan Purchases
Background: Purchases of foods containing nonnutritive sweetener (NNS) alone or in combination with caloric sweeteners (CS) has increased in recent years in the United States. At the same time clinical evidence is emerging of different cardiometabolic effects of each NNS type. Objective: To examine the prevalence and volume purchased of commonly consumed types of NNS in packaged food and beverage products comparing 2002 and 2018 using data from nationally representative samples of US households. Participants/setting: Nielsen Homescan Consumer Panels (The Nielsen Company); 2002 and 2018. Main outcome measures: Prevalence and volume of foods and beverages purchased containing CS, NNS, both CS and NNS, or neither CS nor NNS, as well as prevalence and volume of products containing specific NNS types. Statistical analyses performed: Differences examined using Student t test, P value of <.05 considered significant. Results: Volume of products purchased containing CS decreased comparing 2002 and 2018 (436.6 ± 1.6 to 362.4 ± 1.3 g/d; P <.05), yet increased for products containing both CS and NNS (10.8-36.2 g/d; P <.05). Regarding specific types of NNS, changes were noted in the prevalence of households purchasing products containing saccharin (1.3%-1.1%; P <.05), aspartame (60.0%-49.4%; P <.05), rebaudioside A (0.1%-25.9%) and sucralose (38.7%-71.0%). Non-Hispanic whites purchased twice the volume of products containing NNS compared to Hispanics and non-Hispanic blacks in both years. Beverages were predominantly responsible for larger volume per capita purchases of products containing only NNS as well as both CS and NNS. Conclusions: A decline in purchases of products containing CS occurred in tandem with an increase in purchases of products containing both CS and NNS, along with a large shift in the specific types of NNS being purchased by US households. New NNS types enter the market regularly, and it is important to monitor changes in the amount of NNS and products containing NNS that consumers purchase
Persistent disparities over time in the distribution of sugar-sweetened beverage intake among children in the United States
Background Recent research suggests that sugar-sweetened beverage (SSB) consumption has been declining among US children aged 2-18 y. However, most studies focused on changes in mean intake, ignore high SSB consumers and do not examine intake among vulnerable groups and, including adolescents, low-income households, and several racial/ethnic minorities. Objective The aim was to estimate usual SSB intake from NHANES surveys from 2003-2004 to 2013-2014 to examine shifts at both the median and 90th percentile among US children, evaluating the extent to which intake disparities in total SSBs and subtypes have persisted. Design Children 2-18 y from NHANES 2003, 2005, 2007, 2009, 2011 and 2013. SSBs were all non-diet beverages sweetened with sugars including revising all beverages to as consumed status and excluding soy and dairy based beverages. The NCI usual intake method was used to estimate usual intake from two 24-hour recalls. A 2-part correlated model accounted for nonconsumers. Quantile regression was then used to examine differences in SSB usual intakes at the 50th and 90th percentiles by race-ethnicity, and examine interactions indicating whether racial-ethnic disparities in intake were modified by income. Results Despite considerable declines, children's SSB intake remains high, particularly among heavy consumers. Among adolescents, median SSB intake in 2013-2014 was on the order of 150-200 kcal/d, and heavy intake at the 90th percentile was on the order of 250-300 kcal/d. There were important disparities in intake that persisted over time. Although high household income was associated with lower SSB intake in non-Hispanic white (NHW) children, intakes of non-Hispanic black (NHB) and Mexican-American (MA) children from these households were similar to or higher than those from poor households. There were also large racial/ethnic differences in the types of SSBs consumed. The consumption of regular sodas by NHB children was somewhat lower than among MA and NHW children, whereas fruit drink intake was markedly higher. Conclusions Overall, these findings suggest that, despite recent declines, strategies are needed to further reduce SSB consumption, and particularly heavy intake, especially among NHB children where fruit drinks also are key source of SSBs
Development of a food composition database to monitor changes in packaged foods and beverages
In order to monitor nutritional changes in the US food supply and assess potential impact on individual dietary intake, an approach was developed to enhance existing standard food composition tables with time-varying product- and brand-specific information for barcoded packaged foods. A âCrosswalkâ was formed between barcoded products and USDA foodcodes in a time-specific manner, such that sales-weighted average nutritional profiles were generated for each foodcode based on corresponding products (275,000â350,000 per 2-year cycle). This Crosswalk-enhanced food composition table was applied to dietary intake data from the National Health and Nutrition Examination Survey (cycles 2007â2008, 2009â2010, and 2011â2012). Total energy density of foods consumed by Americans from stores/vending was stable over time and differed by <5 kcal/100 g using the Crosswalk-enhanced vs standard database. However, changes in the energy density of food groups were found utilizing the Crosswalk that were not detected using the standard database. Likewise, significant declines in energy intake from beverages among children (288 ± 7.3 to 258 ± 6.8 kcal/d) were found using the Crosswalk-enhanced database but were non-significant using the standard database. The Crosswalk approach can potentially augment national nutrition surveys by utilizing commercial food purchase and nutrient databases to capture changes in the nutrient content of packaged foods
Reading Ronaldo: contingent whiteness in the football media
Ever since his introduction to the first-Â-team at Manchester United FC, Cristiano Ronaldo Dos Santos Aveiro has been recognised as one of the footballing worldâs most stand-Â-out football players. In turn, Ronaldo has drawn the attention of scholars working across a number of disciplines. While sports economists and sociologists of sport, amongst others, have contributed to a growing literature about Ronaldo and the social implications of his on and off-Â-field behaviour, few critical analyses have considered the racialised aspects of Ronaldoâs representations, or how audiences make sense of his racialised or ethnic identity. Using images of Ronaldo, which we presented to and discussed with self-Â-identified physically active white British men, we explore what it is representations and audience interpretations of Ronaldo reveal about the complexities of white male identity formation. We do this to understand better how white male identities can be read and interpreted through and in the context of football. Facilitated by our conception of contingent whiteness, we argue that white British menâs interpretations of Ronaldoâs whiteness are inextricably linked to discourses of âraceâ, masculinities and football
Re-creation of site-specific multi-directional waves with non-collinear current
Site-specific wave data can be used to improve the realism of tank test conditions and resulting outputs. If this data is recorded in the presence of a current, then the combined conditions must be re-created to ensure wave power, wavelength and steepness are correctly represented in a tank. In this paper we explore the impacts of currents on the wave field and demonstrate a simple, effective methodology for re-creating combined wave-current scenarios. Regular waves, a parametric unidirectional spectrum, and a complex site-specific directional sea state were re-created with current velocities representing 0.25, 0.5, and 1.0 m/s full scale. Waves were generated at a number of angles relative to the current, providing observations of both collinear and non-collinear wave-current interactions. Wave amplitudes transformed by the current were measured and corrected linearly, ensuring desired frequency and wavenumber spectra in the presence of current were obtained. This empirical method proved effective after a single iteration. Frequency spectra were within 3% of desired and wave heights normally within 1%. The generation-measurement-correction procedure presented enables effective re-creation of complex wave-current scenarios. This capability will increase the realism of tank testing, and help de-risk devices prior to deployment at sea
Proteogenomic landscape of breast cancer tumorigenesis and targeted therapy
The integration of mass spectrometry-based proteomics with next-generation DNA and RNA sequencing profiles tumors more comprehensively. Here this "proteogenomics" approach was applied to 122 treatment-naive primary breast cancers accrued to preserve post-translational modifications, including protein phosphorylation and acetylation. Proteogenomics challenged standard breast cancer diagnoses, provided detailed analysis of the ERBB2 amplicon, defined tumor subsets that could benefit from immune checkpoint therapy, and allowed more accurate assessment of Rb status for prediction of CDK4/6 inhibitor responsiveness. Phosphoproteomics profiles uncovered novel associations between tumor suppressor loss and targetable kinases. Acetylproteome analysis highlighted acetylation on key nuclear proteins involved in the DNA damage response and revealed cross-talk between cytoplasmic and mitochondrial acetylation and metabolism. Our results underscore the potential of proteogenomics for clinical investigation of breast cancer through more accurate annotation of targetable pathways and biological features of this remarkably heterogeneous malignancy
Playing dead to stay alive: death-feigning in Liolaemus occipitalis (Squamata: Liolaemidae)
PatogĂȘnese, sinais clĂnicos e patologia das doenças causadas por plantas hepatotĂłxicas em ruminantes e eqĂŒinos no Brasil
Large-scale discovery of novel genetic causes of developmental disorders
Despite three decades of successful, predominantly phenotype-driven discovery of the genetic causes of monogenic disorders1, up to half of children with severe developmental disorders of probable genetic origin remain without a genetic diagnosis. Particularly challenging are those disorders rare enough to have eluded recognition as a discrete clinical entity, those with highly variable clinical manifestations, and those that are difficult to distinguish from other, very similar, disorders. Here we demonstrate the power of using an unbiased genotype-driven approach2 to identify subsets of patients with similar disorders. By studying 1,133 children with severe, undiagnosed developmental disorders, and their parents, using a combination of exome sequencing3,4,5,6,7,8,9,10,11 and array-based detection of chromosomal rearrangements, we discovered 12 novel genes associated with developmental disorders. These newly implicated genes increase by 10% (from 28% to 31%) the proportion of children that could be diagnosed. Clustering of missense mutations in six of these newly implicated genes suggests that normal development is being perturbed by an activating or dominant-negative mechanism. Our findings demonstrate the value of adopting a comprehensive strategy, both genome-wide and nationwide, to elucidate the underlying causes of rare genetic disorders
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