371 research outputs found

    Estimating the burden of COVID-19 on mortality, life expectancy and lifespan inequality in England and Wales : a population-level study

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    Objective: To determine the impact of the COVID-19 pandemic on mortality, life expectancy and lifespan inequality in the first half of 2020 (from week 1 to week 26 starting June 22) in England and Wales. Design: Demographic analysis of all-cause mortality from week 1 through week 26 of 2020 using publicly available death registration data from the Office for National Statistics. Setting and population: England and Wales population by age and sex in 2020. Main outcome measure: Age and sex-specific excess mortality risk and deaths above a baseline adjusted for seasonality in the first half of 2020. We additionally provide estimates of life expectancy at birth and lifespan inequality defined as the standard deviation in age at death. Results: We estimate that there have been 53,937 (95% Prediction Interval: 53,092, 54,746) excess deaths in the first half of 2020, 54% of which occurred in men. Excess deaths increased sharply with age and men experienced elevated risks of death in all age groups. Life expectancy at birth dropped 1.7 and 1.9 years for females and males relative to the 2019 levels, respectively. Lifespan inequality also fell over the same period. Conclusions: Quantifying excess deaths and their impact on life expectancy at birth provides a more comprehensive picture of the full COVID-19 burden on mortality. Whether mortality will return to - or even fall below - the baseline level remains to be seen as the pandemic continues to unfold and diverse interventions are put in place

    Blood lead levels in pregnant women of high and low socioeconomic status in Mexico City.

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    This study examined the determinants of blood lead (BPb) in 513 pregnant women in Mexico City: 311 from public hospital prenatal clinics, representing primarily women of low socioeconomic status (SES), and 202 from private hospitals, primarily women of high SES. Overall, BPb levels ranged from 1.38 to 29 micrograms/dl, with geometric means of 6.7 and 11.12 micrograms/dl for women from private and public hospitals, respectively. The crude geometric means difference obtained by t-test was 4.42 (p < 0.001). BPb was measured from January 1994 to August 1995 and showed higher levels during fall and winter and lower levels during spring and summer. The main BPb determinants were the use of lead-glazed ceramics in women from public hospitals and season of the year in women from private hospitals. Consumption of tortillas (corn bread rich in calcium) decreased BPb levels in the lower SES group, but the relationship was not statistically significant (p > 0.05). Consumption of milk products significantly (p < 0.05) reduced BPb levels in the higher SES group. In 112 women whose diets were deficient in calcium, taking calcium supplements lowered their blood lead levels about 7 micrograms/dl. A predictive model fitted to these data, using the strongest predictors plus gestational age, showed a difference of 14 micrograms/dl between the best and worst scenarios in women from public hospitals. Avoiding use of lead-glazed ceramics, consuming diets rich in calcium, and, if needed, taking calcium supplements, would be expected to result in substantial lowering of BPb, especially in pregnant women of low socioeconomic status

    Isolation and Selection of Sulfur-oxidizing Bacteria for the Treatment of Sulfur-containing Hazardous Wastes

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    A total of 75 microorganisms were obtained from high-sulfur content environmental samples using different sulfur sources. Fifty-four of them had the ability to oxidize sulfur at 1% (w/v) in liquid culture, however only three of them AZCT-M125-5, AZCT- -M125-6, and AZCT-M125-7 were able to grow autotrophycally using elemental sulfurat concentrations higher than 1 % and up to 9 % (w/v) as energy source. They producemore than 300 mg sulfate/L. Also, these microbial cultures were able to produce sulfate within pH 3 to 7. Analysis based on 16S rRNA gene sequences indicated that microbial cultures AZCT-M125-5 and AZCT-M125-6 were closely related to Acidithiobacillusthiooxidans while identification of AZCT-M125-7 was not possible. According to the results, these three microorganisms can be excellent candidates for the future development of alternative biotechnological processes for the treatment of hazardous wastes containing sulfur

    Impurity Effect on the In-plane Penetration Depth of the Organic Superconductors κ\kappa-(BEDT-TTF)2X_2X (XX = Cu(NCS)2_2 and Cu[N(CN)2_2]Br)

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    We report the in-plane penetration depth λ\lambda_{\parallel} of single crystals κ\kappa-(BEDT-TTF)2X_2X (X=X= Cu(NCS)2_2 and Cu[N(CN)2_2]Br) by means of the reversible magnetization measurements under the control of cooling-rate. In XX = Cu(NCS)2_2, λ(0)\lambda_{\parallel}(0) as an extrapolation toward TT = 0 K does not change by the cooling-rate within the experimental accuracy, while TcT_{\textrm{c}} is slightly reduced. On the other hand, in XX = Cu[N(CN)2_2]Br, λ(0)\lambda_{\parallel}(0) indicates a distinct increase by cooling faster. The different behavior of λ(0)\lambda_{\parallel}(0) on cooling-rate between the two salts is quantitatively explained in terms of the local-clean approximation (London model), considering that the former salt belongs to the very clean system and the later the moderate clean one. The good agreement with this model demonstrates that disorders of ethylene-group in BEDT-TTF introduced by cooling faster increase the electron(quasiparticle)-scattering, resulting in shorter mean free path.Comment: 8 pages, 9 figure

    Approximate Ginzburg-Landau solution for the regular flux-line lattice. Circular cell method

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    A variational model is proposed to describe the magnetic properties of type-II superconductors in the entire field range between Hc1H_{c1} and Hc2H_{c2} for any values of the Ginzburg-Landau parameter κ>1/2\kappa>1/\sqrt{2}. The hexagonal unit cell of the triangular flux-line lattice is replaced by a circle of the same area, and the periodic solutions to the Ginzburg-Landau equations within this cell are approximated by rotationally symmetric solutions. The Ginzburg-Landau equations are solved by a trial function for the order parameter. The calculated spatial distributions of the order parameter and the magnetic field are compared with the corresponding distributions obtained by numerical solution of the Ginzburg-Landau equations. The comparison reveals good agreement with an accuracy of a few percent for all κ\kappa values exceeding κ1\kappa \approx 1. The model can be extended to anisotropic superconductors when the vortices are directed along one of the principal axes. The reversible magnetization curve is calculated and an analytical formula for the magnetization is proposed. At low fields, the theory reduces to the London approach at κ1\kappa \gg 1, provided that the exact value of Hc1H_{c1} is used. At high fields, our model reproduces the main features of the well-known Abrikosov theory. The magnetic field dependences of the reversible magnetization found numerically and by our variational method practically coincide. The model also refines the limits of some approximations which have been widely used. The calculated magnetization curves are in a good agreement with experimental data on high-Tc_c superconductors.Comment: 8 pages, RevTex, 6 figures, submitted to Phys. Rev.

    Evidence for structural and electronic instabilities at intermediate temperatures in κ\kappa-(BEDT-TTF)2_{2}X for X=Cu[N(CN)2_{2}]Cl, Cu[N(CN)2_{2}]Br and Cu(NCS)2_{2}: Implications for the phase diagram of these quasi-2D organic superconductors

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    We present high-resolution measurements of the coefficient of thermal expansion α(T)=lnl(T)/T\alpha (T)=\partial \ln l(T)/\partial T of the quasi-twodimensional (quasi-2D) salts κ\kappa-(BEDT-TTF)2_2X with X = Cu(NCS)2_2, Cu[N(CN)2_2]Br and Cu[N(CN)2_2]Cl. At intermediate temperatures (B), distinct anomalies reminiscent of second-order phase transitions have been found at T=38T^\ast = 38 K and 45 K for the superconducting X = Cu(NCS)2_2 and Cu[N(CN)2_2]Br salts, respectively. Most interestingly, we find that the signs of the uniaxial pressure coefficients of TT^\ast are strictly anticorrelated with those of TcT_c. We propose that TT^\ast marks the transition to a spin-density-wave (SDW) state forming on minor, quasi-1D parts of the Fermi surface. Our results are compatible with two competing order parameters that form on disjunct portions of the Fermi surface. At elevated temperatures (C), all compounds show α(T)\alpha (T) anomalies that can be identified with a kinetic, glass-like transition where, below a characteristic temperature TgT_g, disorder in the orientational degrees of freedom of the terminal ethylene groups becomes frozen in. We argue that the degree of disorder increases on going from the X = Cu(NCS)2_2 to Cu[N(CN)2_2]Br and the Cu[N(CN)2_2]Cl salt. Our results provide a natural explanation for the unusual time- and cooling-rate dependencies of the ground-state properties in the hydrogenated and deuterated Cu[N(CN)2_2]Br salts reported in the literature.Comment: 22 pages, 7 figure

    Ten-year follow-up of giant basilar aneurysm treated by sole stenting technique: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>The sole stenting technique has emerged as a new tool for the management of intracranial aneurysms. However, several concerns have emerged about the long-term behavior of intracranial stents, particularly their safety and efficacy.</p> <p>Case presentation</p> <p>We present the first case of an intracranial aneurysm intentionally treated with the sole stenting technique. After ten years of clinical and imaging follow-up, the lesion has healed and no intrastent stenosis is observed.</p> <p>Several issues concerning this technique are discussed. For instance, the modification of the angle and intra-aneurysmal thrombosis may account as positive effects; negative outcomes include in-stent thrombosis or stenosis.</p> <p>Conclusions</p> <p>This case report, involving a long clinical and imaging follow-up, provides an example of the effectiveness, safety, durability and simplicity of the sole stenting technique in the management of intracranial aneurysms.</p

    The long lives of primates and the ‘invariant rate of ageing’ hypothesis

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    Is it possible to slow the rate of ageing, or do biological constraints limit its plasticity? We test the ‘invariant rate of ageing’ hypothesis, which posits that the rate of ageing is relatively fixed within species, with a collection of 39 human and nonhuman primate datasets across seven genera. We first recapitulate, in nonhuman primates, the highly regular relationship between life expectancy and lifespan equality seen in humans. We next demonstrate that variation in the rate of ageing within genera is orders of magnitude smaller than variation in pre-adult and age-independent mortality. Finally, we demonstrate that changes in the rate of ageing, but not other mortality parameters, produce striking, species-atypical changes in mortality patterns. Our results support the invariant rate of ageing hypothesis, implying biological constraints on how much the human rate of ageing can be slowed

    The Dependence of the Superconducting Transition Temperature of Organic Molecular Crystals on Intrinsically Non-Magnetic Disorder: a Signature of either Unconventional Superconductivity or Novel Local Magnetic Moment Formation

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    We give a theoretical analysis of published experimental studies of the effects of impurities and disorder on the superconducting transition temperature, T_c, of the organic molecular crystals kappa-ET_2X and beta-ET_2X (where ET is bis(ethylenedithio)tetrathiafulvalene and X is an anion eg I_3). The Abrikosov-Gorkov (AG) formula describes the suppression of T_c both by magnetic impurities in singlet superconductors, including s-wave superconductors and by non-magnetic impurities in a non-s-wave superconductor. We show that various sources of disorder lead to the suppression of T_c as described by the AG formula. This is confirmed by the excellent fit to the data, the fact that these materials are in the clean limit and the excellent agreement between the value of the interlayer hopping integral, t_perp, calculated from this fit and the value of t_perp found from angular-dependant magnetoresistance and quantum oscillation experiments. If the disorder is, as seems most likely, non-magnetic then the pairing state cannot be s-wave. We show that the cooling rate dependence of the magnetisation is inconsistent with paramagnetic impurities. Triplet pairing is ruled out by several experiments. If the disorder is non-magnetic then this implies that l>=2, in which case Occam's razor suggests that d-wave pairing is realised. Given the proximity of these materials to an antiferromagnetic Mott transition, it is possible that the disorder leads to the formation of local magnetic moments via some novel mechanism. Thus we conclude that either kappa-ET_2X and beta-ET_2X are d-wave superconductors or else they display a novel mechanism for the formation of localised moments. We suggest systematic experiments to differentiate between these scenarios.Comment: 18 pages, 5 figure
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