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Associations of Blood Pressure and Cholesterol Levels During Young Adulthood With Later Cardiovascular Events.
BackgroundBlood pressure (BP) and cholesterol are major modifiable risk factors for cardiovascular disease (CVD), but effects of exposures during young adulthood on later life CVD risk have not been well quantified.ObjectiveThe authors sought to evaluate the independent associations between young adult exposures to risk factors and later life CVD risk, accounting for later life exposures.MethodsThe authors pooled data from 6 U.S. cohorts with observations spanning the life course from young adulthood to later life, and imputed risk factor trajectories for low-density lipoprotein (LDL) and high-density lipoprotein cholesterols, systolic and diastolic BP starting from age 18 years for every participant. Time-weighted average exposures to each risk factor during young (age 18 to 39 years) and later adulthood (age ≥40 years) were calculated and linked to subsequent risks of coronary heart disease (CHD), heart failure (HF), or stroke.ResultsA total of 36,030 participants were included. During a median follow-up of 17 years, there were 4,570 CHD, 5,119 HF, and 2,862 stroke events. When young and later adult risk factors were considered jointly in the model, young adult LDL ≥100 mg/dl (compared with <100 mg/dl) was associated with a 64% increased risk for CHD, independent of later adult exposures. Similarly, young adult SBP ≥130 mm Hg (compared with <120 mm Hg) was associated with a 37% increased risk for HF, and young adult DBP ≥80 mm Hg (compared with <80 mm Hg) was associated with a 21% increased risk.ConclusionsCumulative young adult exposures to elevated systolic BP, diastolic BP and LDL were associated with increased CVD risks in later life, independent of later adult exposures
The political import of deconstruction—Derrida’s limits?: a forum on Jacques Derrida’s specters of Marx after 25 Years, part I
Jacques Derrida delivered the basis of The Specters of Marx: The State of the Debt, the Work of Mourning, & the New International as a plenary address at the conference ‘Whither Marxism?’ hosted by the University of California, Riverside, in 1993. The longer book version was published in French the same year and appeared in English and Portuguese the following year. In the decade after the publication of Specters, Derrida’s analyses provoked a large critical literature and invited both consternation and celebration by figures such as Antonio Negri, Wendy Brown and Frederic Jameson. This forum seeks to stimulate new reflections on Derrida, deconstruction and Specters of Marx by considering how the futures past announced by the book have fared after an eventful quarter century. Maja Zehfuss, Antonio Vázquez-Arroyo and Dan Bulley and Bal Sokhi-Bulley offer sharp, occasionally exasperated, meditations on the political import of deconstruction and the limits of Derrida’s diagnoses in Specters of Marx but also identify possible paths forward for a global politics taking inspiration in Derrida’s work of the 1990s
Time- and momentum-resolved photoemission studies using time-of-flight momentum microscopy at a free-electron laser
Time-resolved photoemission with ultrafast pump and probe pulses is an emerging technique with wide application potential. Real-time recording of nonequilibrium electronic processes, transient states in chemical reactions, or the interplay of electronic and structural dynamics offers fascinating opportunities for future research. Combining valence-band and core-level spectroscopy with photoelectron diffraction for electronic, chemical, and structural analyses requires few 10 fs soft X-ray pulses with some 10 meV spectral resolution, which are currently available at high repetition rate free-electron lasers. We have constructed and optimized a versatile setup commissioned at FLASH/PG2 that combines free-electron laser capabilities together with a multidimensional recording scheme for photoemission studies. We use a full-field imaging momentum microscope with time-of-flight energy recording as the detector for mapping of 3D band structures in (kx, ky, E) parameter space with unprecedented efficiency. Our instrument can image full surface Brillouin zones with up to 7 Å−1 diameter in a binding-energy range of several eV, resolving about 2.5 × 105 data voxels simultaneously. Using the ultrafast excited state dynamics in the van der Waals semiconductor WSe2 measured at photon energies of 36.5 eV and 109.5 eV, we demonstrate an experimental energy resolution of 130 meV, a momentum resolution of 0.06 Å−1, and a system response function of 150 fs
Classifying Chronic Lower Respiratory Disease Events in Epidemiologic Cohort Studies
Rationale: One in 12 adults has chronic obstructive pulmonary disease or asthma. Acute exacerbations of these chronic lower respiratory diseases (CLRDs) are a major cause of morbidity and mortality. Valid approaches to classifying cases and exacerbations in the general population are needed to facilitate prevention research
Dressed-state amplification by a superconducting qubit
We demonstrate amplification of a microwave signal by a strongly driven
two-level system in a coplanar waveguide resonator. The effect known from
optics as dressed-state lasing is observed with a single quantum system formed
by a persistent current (flux) qubit. The transmission through the resonator is
enhanced when the Rabi frequency of the driven qubit is tuned into resonance
with one of the resonator modes. Amplification as well as linewidth narrowing
of a weak probe signal has been observed. The laser emission at the resonator's
fundamental mode has been studied by measuring the emission spectrum. We
analyzed our system and found an excellent agreement between the experimental
results and the theoretical predictions obtained in the dressed-state model.Comment: 5 pages, 4 figure
Stepping closer to pulsed single microwave photon detectors for axions search
Axions detection requires the ultimate sensitivity down to the single photon
limit. In the microwave region this corresponds to energies in the yJ range.
This extreme sensitivity has to be combined with an extremely low dark count
rate, since the probability of axions conversion into microwave photons is
supposed to be very low. To face this complicated task, we followed two
promising approaches that both rely on the use of superconducting devices based
on the Josephson effect. The first one is to use a single Josephson junction
(JJ) as a switching detector (i.e. exploiting the superconducting to normal
state transition in presence of microwave photons). We designed a device
composed of a coplanar waveguide terminated on a current biased Josephson
junction. We tested its efficiency to pulsed (pulse duration 10 ns) microwave
signals, since this configuration is closer to an actual axions search
experiment. We show how our device is able to reach detection capability of the
order of 10 photons with frequency 8 GHz. The second approach is based on an
intrinsically quantum device formed by two resonators coupled only via a
superconducting qubit network (SQN). This approach relies on quantum
nondemolition measurements of the resonator photons. We show that injecting RF
power into the resonator, the frequency position of the resonant drop in the
transmission coefficient (S21) can be modulated up to 4 MHz. We anticipate
that, once optimized, both the devices have the potential to reach single
photon sensitivity
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