Quantile regression for mixed models with an application to examine blood pressure trends in China

Cardiometabolic diseases have substantially increased in China in the past 20 years and blood pressure is a primary modifiable risk factor. Using data from the China Health and Nutrition Survey, we examine blood pressure trends in China from 1991 to 2009, with a concentration on age cohorts and urbanicity. Very large values of blood pressure are of interest, so we model the conditional quantile functions of systolic and diastolic blood pressure. This allows the covariate effects in the middle of the distribution to vary from those in the upper tail, the focal point of our analysis. We join the distributions of systolic and diastolic blood pressure using a copula, which permits the relationships between the covariates and the two responses to share information and enables probabilistic statements about systolic and diastolic blood pressure jointly. Our copula maintains the marginal distributions of the group quantile effects while accounting for within-subject dependence, enabling inference at the population and subject levels. Our population-level regression effects change across quantile level, year and blood pressure type, providing a rich environment for inference. To our knowledge, this is the first quantile function model to explicitly model within-subject autocorrelation and is the first quantile function approach that simultaneously models multivariate conditional response. We find that the association between high blood pressure and living in an urban area has evolved from positive to negative, with the strongest changes occurring in the upper tail. The increase in urbanization over the last twenty years coupled with the transition from the positive association between urbanization and blood pressure in earlier years to a more uniform association with urbanization suggests increasing blood pressure over time throughout China, even in less urbanized areas. Our methods are available in the R package BSquare.Comment: Published at http://dx.doi.org/10.1214/15-AOAS841 in the Annals of Applied Statistics (http://www.imstat.org/aoas/) by the Institute of Mathematical Statistics (http://www.imstat.org

Sequence stratigraphy, chemostratigraphy and facies analysis of Cambrian Series 2 – Series 3 boundary strata in northwestern Scotland

Globally, the Series 2 – Series 3 boundary of the Cambrian System coincides with a major carbon isotope excursion, sea-level changes and trilobite extinctions. Here we examine the sedimentology, sequence stratigraphy and carbon isotope record of this interval in the Cambrian strata (Durness Group) of NW Scotland. Carbonate carbon isotope data from the lower part of the Durness Group (Ghrudaidh Formation) show that the shallow-marine, Laurentian margin carbonates record two linked sea-level and carbon isotopic events. Whilst the carbon isotope excursions are not as pronounced as those expressed elsewhere, correlation with global records (Sauk I – Sauk II boundary and Olenellus biostratigraphic constraint) identifies them as representing the local expression of the ROECE and DICE. The upper part of the ROECE is recorded in the basal Ghrudaidh Formation whilst the DICE is seen around 30m above the base of this unit. Both carbon isotope excursions co-occur with surfaces interpreted to record regressive–transgressive events that produced amalgamated sequence boundaries and ravinement/flooding surfaces overlain by conglomerates of reworked intraclasts. The ROECE has been linked with redlichiid and olenellid trilobite extinctions, but in NW Scotland, Olenellus is found after the negative peak of the carbon isotope excursion but before sequence boundary formation

EarthPT: a foundation model for Earth Observation

We introduce EarthPT -- an Earth Observation (EO) pretrained transformer. EarthPT is a 700 million parameter decoding transformer foundation model trained in an autoregressive self-supervised manner and developed specifically with EO use-cases in mind. We demonstrate that EarthPT is an effective forecaster that can accurately predict future pixel-level surface reflectances across the 400-2300 nm range well into the future. For example, forecasts of the evolution of the Normalised Difference Vegetation Index (NDVI) have a typical error of approximately 0.05 (over a natural range of -1 -> 1) at the pixel level over a five month test set horizon, out-performing simple phase-folded models based on historical averaging. We also demonstrate that embeddings learnt by EarthPT hold semantically meaningful information and could be exploited for downstream tasks such as highly granular, dynamic land use classification. Excitingly, we note that the abundance of EO data provides us with -- in theory -- quadrillions of training tokens. Therefore, if we assume that EarthPT follows neural scaling laws akin to those derived for Large Language Models (LLMs), there is currently no data-imposed limit to scaling EarthPT and other similar `Large Observation Models.'Comment: 7 pages, 4 figures, submitted to NeurIPS CCAI worksho

Perturbative Strong Interaction Corrections to the Heavy Quark Semileptonic Decay Rate

We calculate the part of the order $\alpha_s^2$ correction to the semileptonic heavy quark decay rate proportional to the number of light quark flavors, and use our result to set the scale for evaluating the strong coupling in the order $\alpha_s$ term according to the scheme of Brodsky, Lepage and Mackenzie. Expressing the decay rate in terms of the heavy quark pole mass $m_Q$, we find the scale for the $\overline{MS}$ strong coupling to be $0.07\, m_Q$. If the decay rate is expressed in terms of the $\overline{MS}$ heavy quark mass $\overline m_Q(m_Q)$ then the scale is $0.12\, m_Q$. We use these results along with the existing calculations for hadronic $\tau$ decay to calculate the BLM scale for the nonleptonic decay width and the semileptonic branching ratio. The implications for the value of $|V_{bc}|$ extracted from the inclusive semileptonic $B$ meson decay rate are discussed.Comment: 7 pages in Latex plus 1 uuencoded figure, uses epsf, UTPT-94-24, CMU-HEP 94-29, CALT-68-1950 (previous results unchanged; we add a short discussion of nonleptonic decays

Familial colloid cyst of the third ventricle

A grant from the One-University Open Access Fund at the University of Kansas was used to defray the author's publication fees in this Open Access journal. The Open Access Fund, administered by librarians from the KU, KU Law, and KUMC libraries, is made possible by contributions from the offices of KU Provost, KU Vice Chancellor for Research & Graduate Studies, and KUMC Vice Chancellor for Research. For more information about the Open Access Fund, please see http://library.kumc.edu/authors-fund.xml.Colloid cysts of the third ventricle are rare benign lesions. They can present as incidental finding on imaging or with symptoms of obstructive hydrocephalus. To date, 18 familial cases of colloid cyst have been reported. Due to the extreme rarity of these cysts, it has been suggested that there is a genetic component involved. This report presents a familial colloid cyst in non-twin brothers who both presented in their early twenties. In addition, both of them had congenital inguinal hernia. This may represent a potential association between familial colloid cysts and congenital inguinal hernia that could provide us with insight into the genetic mechanism involved

What Will it Take to Make Solar Panels Cool?

With the predicted results of climate change looming, humanity must do all it can to limit greenhouse gas emissions. Maintaining a habitable environment along with the high quality of living associated with developed nations requires investment in renewable energy. Because national governments often fail to make responsible decisions for their country\u27s future, this burden falls to institutions like UMass Amherst. Although costly investments like solar panels substantially improve the sustainability of campus, some innovative improvements of existing solar energy infrastructure can go a long way. For example, when solar panels heat up they lose photovoltaic efficiency. We propose that UMass institute cooling systems on current and future solar panel structures. This may sound extravagant, but in this paper we outline a plan for a simple and affordable cooling system that can be constructed from supplies bought at a local hardware store. The University spent approximately $1.5 million dollars on the new solar canopy atop the Robsham’s Visitor Center. This structure generates an estimated$40,000 worth of electricity each year, with a 38 year return on investment. We expect a cooling system for each canopy to cost around $500 and to improve power output by more than 10 percent. This means that by the most conservative estimate, a$500 investment will generate an additional $4,000 worth of electricity, reducing the return on investment time by 4 years. Compared with the initial solar canopy investment, this magnitude of electricity generation would have cost$150,000. By comparison, $500 is peanuts. Read on to see how a little ingenuity can go a long way to save money and the environment

Lack of correlation between MYCN expression and the Warburg effect in neuroblastoma cell lines

<p>Abstract</p> <p>Background</p> <p>Many cancers preferentially meet their energy requirements through the glycolytic pathway rather than via the more efficient oxidative phosphorylation pathway. It is thought that this is an important adaptation in cancer malignancy. We investigated whether use of glycolysis for energy production even in the presence of oxygen (known as the Warburg effect) varied between neuroblastoma cell lines with or without <it>MYCN </it>amplification (a key indicator of poor disease outcome in neuroblastoma).</p> <p>Methods</p> <p>We examined ATP and lactate production, oxygen consumption and mitochondrial energisation status for three neuroblastoma cell lines with varying degrees of <it>MYCN </it>amplification and MYCN expression.</p> <p>Results</p> <p>We found no correlation between MYCN expression and the Warburg effect in the cell lines investigated.</p> <p>Conclusion</p> <p>Our results suggest preferential use of glycolysis for energy production and MYCN expression may be independent markers of neuroblastoma malignancy <it>in vitro </it>if not <it>in vivo</it>.</p

Hadron Spectra for Semileptonic Heavy Quark Decay

We calculate the leading perturbative and power corrections to the hadronic invariant mass and energy spectra in semileptonic heavy hadron decays. We apply our results to the $B$ system. Moments of the invariant mass spectrum, which vanish in the parton model, probe gluon bremsstrahlung and nonperturbative effects. Combining our results with recent data on $B$ meson branching ratios, we obtain a lower bound $\bar\Lambda>410\,{\rm MeV}$ and an upper bound $m_b^{\rm pole}<4.89\,$GeV. The Brodsky-Lepage-Mackenzie scale setting procedure suggests that higher order perturbative corrections are small for bottom decay, and even tractable for charm decay.Comment: 24 pages, uses REVTeX, 5 EPS figures embedded with epsf.sty, slightly modified version to appear in Phys. Rev.

Parental influences on child physical activity and screen viewing time: a population based study

Background: Parents can influence their children’s physical activity participation and screen time.This study examined the relative significance of perceived parental barriers and self-efficacy in relation to children’s physical activity participation and screen time viewing. The associations between these factors and the behaviours were analysed. Methods: Cross-sectional population survey in New South Wales, Australia of parents of pre-school (N = 764), younger (Kindergarten, Grades 2 and 4; N = 1557) and older children (Grades 6, 8 and 10; N = 1665). Parents reported barriers and self-efficacy to influence their child’s physical activity and screen time behaviours in a range of circumstances. Differences were examined by child’s sex and age group, household income, maternal education and location of residence. The duration of physical activity and screen viewing was measured by parental report for pre-school and younger children and self-report for older children. Associations between parental factors and children’s organised, non-organised and total activity and screen time were analysed. Results: Cost, lack of opportunities for participation and transport problems were the barriers most often reported, particularly by low income parents and those in rural areas. The number of barriers was inversely related to children’s time spent in organised activity, but not their non-organised activity. Higher parental self-efficacy was positively associated with organised physical activity in the younger and older children’s groups and the non-organised activity of older children. School-age children (younger and older groups) were less likely to meet physical activity guidelines when parents reported ≥4 barriers (OR 3.76, 95% CI 1.25-11.34 and OR 3.72, 95% CI 1.71-8.11 respectively). Low parental self-efficacy was also associated with the likelihood of children exceeding screen time guidelines for each age group (pre-school OR 0.62, 95% CI 0.43-0.87; young children OR 0.56, 95% CI 0.39-0.80; and older children OR 0.57, 95% CI 0.43-0.74). Conclusion: Parental barriers are associated with the time that children spend in both active and sedentary pursuits. These findings highlight family, economic and environmental factors that should be addressed in programs to promote child physical activity and tackle sedentary behaviour

Hadronic Spectral Moments in Semileptonic B Decays With a Lepton Energy Cut

We compute the first two moments of the final hadronic invariant mass in inclusive semileptonic B decay, in the presence of a cut on the charged lepton energy. These moments may be measured directly by experiments at the Upsilon(4S) using the neutrino reconstruction technique, which requires such a cut. Measurement of these moments will place constraints on the nonperturbative parameters \bar\Lambda and \lambda_1, which are relevant for extracting the quark masses m_b and m_c, as well as the CKM angle V_cb. We include terms of order \alpha_s^2\beta_0 and 1/m_b^3 in the operator product expansion, and use the latter to estimate the theoretical uncertainty in the extraction of \bar\Lambda and \lambda_1.Comment: 13 pages, 5 figures, REVTe