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Photoinduced electron transfer processes in dye-semiconductor systems with different spacer groups

Photoinduced electron transfer processes in perylene-titanium dioxide dye-semiconductor systems are studied. In particular, the influence of saturated and unsaturated aliphatic spacer groups inserted between the chromophore and the semiconductor substrate is investigated. The study is based on a recently developed method that combines first-principles electronic structure calculations to character

Risk of lung cancer by histology among immigrants to Sweden

Background: We wanted to define lung cancer incidence rates by histological subtype among immigrants in Sweden to explore the effect of new environments on the incidence of lung cancer by histological subtype in different ethnic populations. Methods: The nationwide Swedish Family-Cancer Database w used to calculate age-standardized incidence rates (ASR) (per 100,000) and standardized incidence rat

The effects of fly-bys on planetary systems

Most of the observed extrasolar planets are found on tight and often eccentric orbits. The high eccentricities are not easily explained by planet-formation models, which predict that planets should be on rather circular orbits. Here we explore whether fly-bys involving planetary systems with properties similar to those of the gas giants in the Solar system can produce planets with properties simil

Analysis of multi-phase transport phenomena with catalyst reactions in polymer electrolyte membrane fuel cells - A review

A review is presented for two-phase modeling approaches to study various transport processes and reactions in polymer electrolyte membrane (PEM) fuel cells along with some experimental work. It has been noted that water management is still one of the least accurate modeled phenomena. The lackness in complete descriptive models for water management inside PEM fuel cells can be attributed to the com

Emerging Polymorphism in Nanostructured TiO2: Quantum Chemical Comparison of Anatase, Rutile, and Brookite Clusters

Density functional theory (DFT) and time-dependent DFT calculations have been performed on a set of 34 titanium dioxide clusters ((TiO2)(n) with n125) to investigate structural and electronic properties of nanostructured TiO2 (nano-TiO2) materials. The investigated clusters include models of the three low-energy polymorphic forms of TiO2 anatase, rutile, and brookite. A systematic comparison of cl

Dual Metabolic Defects Are Required to Produce Hypertriglyceridemia in Obese Subjects

Objective-Obesity increases the risk of cardiovascular disease and premature death. However, not all obese subjects develop the metabolic abnormalities associated with obesity. The aim of this study was to clarify the mechanisms that induce dyslipidemia in obese subjects. Methods and Results-Stable isotope tracers were used to elucidate the pathophysiology of the dyslipidemia in hypertriglyceridem

New evidence of Holocene atmospheric circulation dynamics based on lake sediments from southern Sweden: a link to the Siberian High

Oxygen (delta O-18) and carbon (delta C-13) isotope records of calcitic carbonate components (Chara sp. algal encrustations and Bithynia tentaculata gastropod opercula) from a lake-sediment succession on the Baltic Sea island of Gotland, south-eastern Sweden, have been obtained to investigate regional climate dynamics during the Holocene. The hydrological sensitivity of the small lake, particularl

Cone-beam differential phase-contrast laminography with x-ray tube source

We report on an x-ray cone-beam differential phase-contrast computed laminography (DPC-CL) method for tomographic reconstruction of thin and lamellar objects. We describe the specific scan geometry of DPC-CL, which consists of a Talbot-Lau grating interferometer and a lab-based x-ray tube source, and derive a filtered back-projection (FBP) reconstruction algorithm. The experimental results of a fl

Using geographical information systems to identify populations in need of improved accessibility to antivenom treatment for snakebite envenoming in costa rica.

INTRODUCTION: Snakebite accidents are an important health problem in rural areas of tropical countries worldwide, including Costa Rica, where most bites are caused by the pit-viper Bothrops asper. The treatment of these potentially fatal accidents is based on the timely administration of specific antivenom. In many regions of the world, insufficient health care systems and lack of antivenom in rem

On the relative rotation of rigid parts and the visco-elastic torsion bushing element

In this paper the interaction between two rigid parts of a multibody, connected by an ideal spherical joint equipped with a visco-elastic torsion bushing element, is derived. The model allows for arbitrary relative rotations of the parts and involves a non-linear torsion stiffness of the bushing. An expression for the interaction between the parts is derived and a specialization to the isotropic b

Animal Models of Diabetic Macrovascular Complications: Key Players in the Development of New Therapeutic Approaches.

Diabetes mellitus is a lifelong, incapacitating metabolic disease associated with chronic macrovascular complications (coronary heart disease, stroke, and peripheral vascular disease) and microvascular disorders leading to damage of the kidneys (nephropathy) and eyes (retinopathy). Based on the current trends, the rising prevalence of diabetes worldwide will lead to increased cardiovascular morbid

Anthropometric measures in relation to risk of heart failure hospitalization: a Swedish population-based cohort study.

BACKGROUND: It is unclear which anthropometric measure is most useful for assessment of the cardiovascular risk. We investigated the association between different anthropometric measures and risk of heart failure (HF) hospitalization. METHODS: BMI, waist-hip ratio (WHR), waist circumference (WC), body fat percentage (BF%), weight and height were measured among 26 653 subjects (aged 45-73 years) wi

The Economy of Undocumented Migration: Taxation and Access to Welfare

A strict division between the formal economy and the informal economy cannot be made and every economic actor has in certain situations a propensity to engage in informal economic activities. The formal, as well as informal economy may lead to economic growth which is essential for a broad welfare policy, under which social benefits are categorized. A person's economic contribution to a state shou

Transport Gap Opening and High On-Off Current Ratio in Trilayer Graphene with Self-Aligned Nanodomain Boundaries.

Trilayer graphene exhibits exceptional electronic properties that are of interest both for fundamental science and for technological applications. The ability to achieve a high on-off current ratio is the central question in this field. Here, we propose a simple method to achieve a current on-off ratio of 10(4) by opening a transport gap in Bernal-stacked trilayer graphene. We synthesized Bernal-s

Conceptions of Decision Quality and Effectiveness in Decision Processes According to Administrative Officers and Investigators Making Decisions for Others in Three Swedish Public Authorities

This study investigated conceptions of decision quality and efficiency held by administrative officers from three Swedish public authorities (the Tax Board, the Social Insurance Agency, and the Police Authority) with respect to decisions made for other people. Research on conceptions of decision quality held by decision makers making decisions for themselves shows that decision outcome is emphasiz

Climate dependent diatom production is preserved in biogenic Si isotope signatures

The aim of this study was to reconstruct diatom production in the subarctic northern tip of the Baltic Sea, Bothnian Bay, based on down-core analysis of Si isotopes in biogenic silica (BSi). Dating of the sediment showed that the samples covered the period 1820 to 2000. The sediment core record can be divided into two periods, an unperturbed period from 1820 to 1950 and a second period affected by

Comparison of floating chamber and eddy covariance measurements of lake greenhouse gas fluxes

Fluxes of carbon dioxide (CO2) and methane (CH4) from lakes may have a large impact on the magnitude of the terrestrial carbon sink. Traditionally lake fluxes have been measured using the floating chamber (FC) technique; however, several recent studies use the eddy covariance (EC) method. We present simultaneous flux measurements using both methods at lake Tamnaren in Sweden during field campaigns