Cu-based metalorganic systems: an ab initio study of the electronic structure

Within a first principles framework, we study the electronic structure of the recently synthesized polymeric coordination compound Cu(II)-2,5-bis(pyrazol-1-yl)-1,4-dihydroxybenzene (CuCCP), which has been suggested to be a good realization of a Heisenberg spin-1/2 chain with antiferromagnetic coupling. By using a combination of classical with ab initio quantum mechanical methods, we design on the computer reliable modified structures of CuCCP aimed at studying effects of Cu-Cu coupling strength variations on this spin-1/2 system. For this purpose, we performed two types of modifications on CuCCP. In one case, we replaced H in the linker by i) an electron donating group (NH2) and ii) an electron withdrawing group (CN), while the other modification consisted in adding H2O and NH3 molecules in the structure which change the local coordination of the Cu(II) ions. With the NMTO-downfolding method we provide a quantitative analysis of the modified electronic structure and the nature of the Cu-Cu interaction paths in these new structures and discuss its implications for the underlying microscopic model.Comment: 18 pages, 11 figures, final versio

The Higher Derivative Expansion of the Effective Action by the String-Inspired Method, Part I

The higher derivative expansion of the one-loop effective action for an external scalar potential is calculated to order O(T**7), using the string-inspired Bern-Kosower method in the first quantized path integral formulation. Comparisons are made with standard heat kernel calculations and with the corresponding Feynman diagrammatic calculation in order to show the efficiency of the present method.Comment: 13 pages, Plain TEX, 1 figure may be obtained from the authors, HD-THEP-93-4

Atopic dermatitis and risk of atrial fibrillation or flutter: A 35-year follow-up study.

BACKGROUND: Atopic dermatitis is characterized by chronic inflammation, which is a risk factor for atrial fibrillation. OBJECTIVE: To examine the association between hospital-diagnosed atopic dermatitis and atrial fibrillation. METHODS: Using linked population-based Danish registries, we identified persons with an inpatient or outpatient hospital diagnosis of atopic dermatitis during 1977-2013 and a comparison cohort individually matched to the atopic dermatitis cohort. We followed cohorts until death, emigration, atrial fibrillation diagnosis, or end of study (January 1, 2013). We compared 35-year risk of atrial fibrillation and estimated hazard ratios with 95% confidence intervals using Cox regression, adjusting for birth year and sex. We validated 100 atopic dermatitis diagnoses from a dermatologic department through medical record review. RESULTS: We included 13,126 persons with atopic dermatitis and 124,211 comparators and followed them for a median of 19.3 years. The 35-year risk of atrial fibrillation was 0.81% and 0.67%, respectively. The positive predictive value of atopic dermatitis diagnoses was 99%. The hazard ratio was 1.2 (95% confidence interval 1.0-1.6) and remained increased after adjusting for various atrial fibrillation risk factors. LIMITATIONS: Analyses were limited to persons with moderate-to-severe atopic dermatitis, and we had no lifestyle data. CONCLUSION: Patients with hospital-diagnosed atopic dermatitis have a 20% increased long-term risk of atrial fibrillation, but the absolute risk remains low

Photon Splitting in a Strong Magnetic Field: Recalculation and Comparison With Previous Calculations

We recalculate the amplitude for photon splitting in a strong magnetic field below the pair production threshold, using the worldline path integral variant of the Bern--Kosower formalism. Numerical comparison (using programs that we have made available for public access on the Internet) shows that the results of the recalculation are identical to the earlier calculations of Adler and later of Stoneham, and to the recent recalculation by Baier, Milstein, and Shaisultanov.Comment: Revtex, 9 pages, no figure

Multiloop Calculations in the String-Inspired Formalism: The Single Spinor-Loop in QED

We use the worldline path-integral approach to the Bern-Kosower formalism for developing a new algorithm for calculation of the sum of all diagrams with one spinor loop and fixed numbers of external and internal photons. The method is based on worldline supersymmetry, and on the construction of generalized worldline Green functions. The two-loop QED $\beta$ -- function is calculated as an example.Comment: uuencoded ps-file, 20 pages, 2 figures, final revised version to appear in Phys. Rev.

A mild, efficient and catalyst-free thermoreversible ligation system based on dithiooxalates

We demonstrate a novel and ready to prepare thermoreversible hetero Diels–Alder dilinker on the basis of dithiooxalates, enabling the mild, rapid and catalyst-free linkage of diverse diene species under ambient conditions for applications in the fields of, for example, modular ligation, self-healing or recyclable materials and surface modification amongst others. The linker was studied using quantum chemical calculations, and experimentally in small molecular reactions via UV/Vis spectroscopy, mass spectrometry and NMR as well as in step-growth polymerizations with diene-difunctional building blocks – characterized via (temperature dependent) SEC and HT NMR – as an example for efficient polymer ligation

Ischaemia-reperfusion injury impairs tissue plasminogen activator release in man

AIMS: Ischaemia-reperfusion (IR) injury causes endothelium-dependent vasomotor dysfunction that can be prevented by ischaemic preconditioning. The effects of IR injury and preconditioning on endothelium-dependent tissue plasminogen activator (t-PA) release, an important mediator of endogenous fibrinolysis, remain unknown. METHODS AND RESULTS: Ischaemia-reperfusion injury (limb occlusion at 200 mmHg for 20 min) was induced in 22 healthy subjects. In 12 subjects, IR injury was preceded by local or remote ischaemic preconditioning (three 5 min episodes of ipsilateral or contralateral limb occlusion, respectively) or sham in a randomized, cross-over trial. Forearm blood flow (FBF) and endothelial t-PA release were assessed using venous occlusion plethysmography and venous blood sampling during intra-arterial infusion of acetylcholine (5-20 µg/min) or substance P (2-8 pmol/min). Acetylcholine and substance P caused dose-dependent increases in FBF (P<0.05 for all). Substance P caused a dose-dependent increase in t-PA release (P<0.05 for all). Acetylcholine and substanceP-mediated vasodilatation and substanceP-mediated t-PA release were impaired following IR injury (P<0.05 for all). Neither local nor remote ischaemic preconditioning protected against the impairment of substance P-mediated vasodilatation or t-PA release. CONCLUSION: Ischaemia-reperfusion injury induced substanceP-mediated, endothelium-dependent vasomotor and fibrinolytic dysfunction in man that could not be prevented by ischaemic preconditioning. CLINICAL TRIAL REGISTRATION INFORMATION: Reference number: NCT00789243, URL: http://clinicaltrials.gov/ct2/show/NCT00789243?term=NCT00789243andrank=1

Evidence for a Rieske-type FeS center in the thermoacidophilic archaebacterium Sulfolobus acidocaldarius

AbstractA high-potential iron-sulfur cluster with characteristics similar to a Rieske-type center was detected in the plasma membrane of Sulfolobus acidocaldarius by EPR spectroscopy. In the reduced form this center has g-values of gz = 2.031, gy = 1.890 and gx = 1.725 (gav = 1.88, rhombicity = 0.37) and its reduction potential at pH 7.4 was determined to be +325 ± 10 mV. The archaebacterial cluster exhibits some unique properties, in comparison to eubacterial and eukaryotic Rieske-type centers. First, the reduction potential is pH-dependent in the range from pH 6.7 to 8.2. Second, the typical inhibitor of Rieske FeS centers, DBMIB, had no effect on the g-values of this cluster. The center is reducible by both NADH and succinate in the presence of cyanide, an inhibitor of the terminal oxidases. The possible role of a Rieske-type center in an organism lacking any c-type cytochromes is discussed

Measuring progress and projecting attainment on the basis of past trends of the health-related Sustainable Development Goals in 188 countries : an analysis from the Global Burden of Disease Study 2016

Background The UN’s Sustainable Development Goals (SDGs) are grounded in the global ambition of “leaving no one behind”. Understanding today’s gains and gaps for the health-related SDGs is essential for decision makers as they aim to improve the health of populations. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2016 (GBD 2016), we measured 37 of the 50 health-related SDG indicators over the period 1990–2016 for 188 countries, and then on the basis of these past trends, we projected indicators to 2030. Methods We used standardised GBD 2016 methods to measure 37 health-related indicators from 1990 to 2016, an increase of four indicators since GBD 2015. We substantially revised the universal health coverage (UHC) measure, which focuses on coverage of essential health services, to also represent personal health-care access and quality for several non-communicable diseases. We transformed each indicator on a scale of 0–100, with 0 as the 2·5th percentile estimated between 1990 and 2030, and 100 as the 97·5th percentile during that time. An index representing all 37 health-related SDG indicators was constructed by taking the geometric mean of scaled indicators by target. On the basis of past trends, we produced projections of indicator values, using a weighted average of the indicator and country-specific annualised rates of change from 1990 to 2016 with weights for each annual rate of change based on out-of-sample validity. 24 of the currently measured health-related SDG indicators have defined SDG targets, against which we assessed attainment. Findings Globally, the median health-related SDG index was 56·7 (IQR 31·9–66·8) in 2016 and country-level performance markedly varied, with Singapore (86·8, 95% uncertainty interval 84·6–88·9), Iceland (86·0, 84·1–87·6), and Sweden (85·6, 81·8–87·8) having the highest levels in 2016 and Afghanistan (10·9, 9·6–11·9), the Central African Republic (11·0, 8·8–13·8), and Somalia (11·3, 9·5–13·1) recording the lowest. Between 2000 and 2016, notable improvements in the UHC index were achieved by several countries, including Cambodia, Rwanda, Equatorial Guinea, Laos, Turkey, and China; however, a number of countries, such as Lesotho and the Central African Republic, but also high-income countries, such as the USA, showed minimal gains. Based on projections of past trends, the median number of SDG targets attained in 2030 was five (IQR 2–8) of the 24 defined targets currently measured. Globally, projected target attainment considerably varied by SDG indicator, ranging from more than 60% of countries projected to reach targets for under-5 mortality, neonatal mortality, maternal mortality ratio, and malaria, to less than 5% of countries projected to achieve targets linked to 11 indicator targets, including those for childhood overweight, tuberculosis, and road injury mortality. For several of the health-related SDGs, meeting defined targets hinges upon substantially faster progress than what most countries have achieved in the past. Interpretation GBD 2016 provides an updated and expanded evidence base on where the world currently stands in terms of the health-related SDGs. Our improved measure of UHC offers a basis to monitor the expansion of health services necessary to meet the SDGs. Based on past rates of progress, many places are facing challenges in meeting defined health-related SDG targets, particularly among countries that are the worst off. In view of the early stages of SDG implementation, however, opportunity remains to take actions to accelerate progress, as shown by the catalytic effects of adopting the Millennium Development Goals after 2000. With the SDGs’ broader, bolder development agenda, multisectoral commitments and investments are vital to make the health-related SDGs within reach of all populations