465 research outputs found
Perspective: the application of a priori diet quality scores to cardiovascular disease risk: a critical evaluation of current scoring systems
Healthy dietary habits are the cornerstone of cardiovascular disease (CVD) prevention. Numerous researchers have developed diet quality indices to help evaluate and compare diet quality across and within various populations. The availability of these new indices raises questions regarding the best selection relevant to a given population. In this perspective, we critically evaluate a priori–defined dietary indices commonly applied in epidemiological studies of CVD risk and mortality. A systematic literature search identified 59 observational studies that applied a priori–defined diet quality indices to CVD risk factors and/or CVD incidence and/or CVD mortality. Among 31 different indices, these scores were categorized as follows: 1) those based on country-specific dietary patterns, 2) those adapted from distinct dietary guidelines, and 3) novel scores specific to key diet-related factors associated with CVD risk. The strengths and limitations of these indices are described according to index components, calculation methods, and the application of these indices to different population groups. Also, the importance of identifying methodological challenges faced by researchers when applying an index are considered, such as selection and weighting of food groups within a score, since food groups are not necessarily equivalent in their associations with CVD. The lack of absolute cutoff values, emphasis on increasing healthy food without limiting unhealthy food intake, and absence of validation of scores with biomarkers or other objective diet assessment methods further complicate decisions regarding the best indices to use. Future research should address these limitations, consider cross-cultural and other differences between population groups, and identify translational challenges inherent in attempting to apply a relevant diet quality index for use in CVD prevention at a population level
Light cigarette smoking increases risk of all-cause and cause-specific mortality: Findings from the NHIS Cohort Study
Very few studies have examined the association between light cigarette smoking (i.e., ≤5 cigarettes per day) and mortality. The aim of this study was to examine the association of light cigarette smoking with all-cause and cause-specific mortality among adults in the United States. Data were from 13 waves of the National Health Interview Survey (1997 to 2009) that were linked to the National Death Index records through December 31, 2011. A total of 329,035 participants aged ≥18 years in the United States were included. Deaths were from all cause, cancer, cardiovascular disease (CVD) and respiratory disease and were confirmed by death certification. During a median follow-up of 8.2 years, 34,862 participants died, of which 8415 were from cancer, 9031 from CVD, and 2040 from respiratory disease. Compared with never-smokers, participants who smoked 1-2 (hazard ratios (HR) = 1.94, 95%CI = 1.73-2.16) and 3-5 cigarettes (HR = 1.99, 1.83-2.17) per day were at higher risk of all-cause mortality after adjustment for demographic variables, lifestyle factors and physician-diagnosis of chronic disease. The associations were stronger for respiratory disease-specific mortality, followed by cancer-specific mortality and CVD-specific mortality. For example, the HRs (95% CIs) of smoking 1-2 cigarettes per day were 9.75 (6.15-15.46), 2.28 (1.84-2.84) and 1.93 (1.58-2.36), respectively, for these three cause-specific mortalities. This study indicates that light cigarette smoking increases risk of all-cause and cause-specific mortality in US adults
Light Cigarette Smoking Increases Risk of All-Cause and Cause-Specific Mortality: Findings from the NHIS Cohort Study
Very few studies have examined the association between light cigarette smoking (i.e., = 18 years in the United States were included. Deaths were from all cause, cancer, cardiovascular disease (CVD) and respiratory disease and were confirmed by death certification. During a median follow-up of 8.2 years, 34,862 participants died, of which 8415 were from cancer, 9031 from CVD, and 2040 from respiratory disease. Compared with never-smokers, participants who smoked 1-2 (hazard ratios (HR) = 1.94, 95%CI = 1.73-2.16) and 3-5 cigarettes (HR = 1.99, 1.83-2.17) per day were at higher risk of all-cause mortality after adjustment for demographic variables, lifestyle factors and physician-diagnosis of chronic disease. The associations were stronger for respiratory disease-specific mortality, followed by cancer-specific mortality and CVD-specific mortality. For example, the HRs (95% CIs) of smoking 1-2 cigarettes per day were 9.75 (6.15-15.46), 2.28 (1.84-2.84) and 1.93 (1.58-2.36), respectively, for these three cause-specific mortalities. This study indicates that light cigarette smoking increases risk of all-cause and cause-specific mortality in US adults
Computing prime factors with a Josephson phase qubit quantum processor
A quantum processor (QuP) can be used to exploit quantum mechanics to find
the prime factors of composite numbers[1]. Compiled versions of Shor's
algorithm have been demonstrated on ensemble quantum systems[2] and photonic
systems[3-5], however this has yet to be shown using solid state quantum bits
(qubits). Two advantages of superconducting qubit architectures are the use of
conventional microfabrication techniques, which allow straightforward scaling
to large numbers of qubits, and a toolkit of circuit elements that can be used
to engineer a variety of qubit types and interactions[6, 7]. Using a number of
recent qubit control and hardware advances [7-13], here we demonstrate a
nine-quantum-element solid-state QuP and show three experiments to highlight
its capabilities. We begin by characterizing the device with spectroscopy.
Next, we produces coherent interactions between five qubits and verify bi- and
tripartite entanglement via quantum state tomography (QST) [8, 12, 14, 15]. In
the final experiment, we run a three-qubit compiled version of Shor's algorithm
to factor the number 15, and successfully find the prime factors 48% of the
time. Improvements in the superconducting qubit coherence times and more
complex circuits should provide the resources necessary to factor larger
composite numbers and run more intricate quantum algorithms.Comment: 5 pages, 3 figure
Coupling Superconducting Qubits via a Cavity Bus
Superconducting circuits are promising candidates for constructing quantum
bits (qubits) in a quantum computer; single-qubit operations are now routine,
and several examples of two qubit interactions and gates having been
demonstrated. These experiments show that two nearby qubits can be readily
coupled with local interactions. Performing gates between an arbitrary pair of
distant qubits is highly desirable for any quantum computer architecture, but
has not yet been demonstrated. An efficient way to achieve this goal is to
couple the qubits to a quantum bus, which distributes quantum information among
the qubits. Here we show the implementation of such a quantum bus, using
microwave photons confined in a transmission line cavity, to couple two
superconducting qubits on opposite sides of a chip. The interaction is mediated
by the exchange of virtual rather than real photons, avoiding cavity induced
loss. Using fast control of the qubits to switch the coupling effectively on
and off, we demonstrate coherent transfer of quantum states between the qubits.
The cavity is also used to perform multiplexed control and measurement of the
qubit states. This approach can be expanded to more than two qubits, and is an
attractive architecture for quantum information processing on a chip.Comment: 6 pages, 4 figures, to be published in Natur
Proximity to Sports Facilities and Sports Participation for Adolescents in Germany
Objectives - To assess the relationship between proximity to specific sports facilities and participation in the corresponding sports activities for adolescents in Germany.
Methods - A sample of 1,768 adolescents aged 11–17 years old and living in 161 German communities was examined. Distances to the nearest sports facilities were calculated as an indicator of proximity to sports facilities using Geographic Information Systems (GIS). Participation in specific leisure-time sports activities in sports clubs was assessed using a self-report questionnaire and individual-level socio-demographic variables were derived from a parent questionnaire. Community-level socio-demographics as covariates were selected from the INKAR database, in particular from indicators and maps on land development. Logistic regression analyses were conducted to examine associations between proximity to the nearest sports facilities and participation in the corresponding sports activities.
Results - The logisitic regression analyses showed that girls residing longer distances from the nearest gym were less likely to engage in indoor sports activities; a significant interaction between distances to gyms and level of urbanization was identified. Decomposition of the interaction term showed that for adolescent girls living in rural areas participation in indoor sports activities was positively associated with gym proximity. Proximity to tennis courts and indoor pools was not associated with participation in tennis or water sports, respectively.
Conclusions - Improved proximity to gyms is likely to be more important for female adolescents living in rural areas
Formation of Super-Earths
Super-Earths are the most abundant planets known to date and are
characterized by having sizes between that of Earth and Neptune, typical
orbital periods of less than 100 days and gaseous envelopes that are often
massive enough to significantly contribute to the planet's overall radius.
Furthermore, super-Earths regularly appear in tightly-packed multiple-planet
systems, but resonant configurations in such systems are rare. This chapters
summarizes current super-Earth formation theories. It starts from the formation
of rocky cores and subsequent accretion of gaseous envelopes. We follow the
thermal evolution of newly formed super-Earths and discuss their atmospheric
mass loss due to disk dispersal, photoevaporation, core-cooling and collisions.
We conclude with a comparison of observations and theoretical predictions,
highlighting that even super-Earths that appear as barren rocky cores today
likely formed with primordial hydrogen and helium envelopes and discuss some
paths forward for the future.Comment: Invited review accepted for publication in the 'Handbook of
Exoplanets,' Planet Formation section, Springer Reference Works, Juan Antonio
Belmonte and Hans Deeg, Ed
The gravitino coupling to broken gauge theories applied to the MSSM
We consider gravitino couplings in theories with broken gauge symmetries. In
particular, we compute the single gravitino production cross section in W+ W-
fusion processes. Despite recent claims to the contrary, we show that this
process is always subdominant to gluon fusion processes in the high energy
limit. The full calculation is performed numerically; however, we give analytic
expressions for the cross section in the supersymmetric and electroweak limits.
We also confirm these results with the use of the effective theory of goldstino
interactions.Comment: 26 pages, 4 figure
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