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High carrier mobility in low band gap polymer-based field-effect transistors

A conjugated polymer with a low band gap of 1.21 eV, i.e., absorbing infrared light, is demonstrated as active material in field-effect transistors (FETs). The material consists of alternating fluorene units and low band gap segments with electron donor-acceptor-donor units composed of two electron-donating thiophene rings attached on both sides of a thiadiazolo-quinoxaline electron-acceptor group

Modulation of the reactivity, stability and substrate- and enantioselectivity of an epoxidation catalyst by noncovalent dynamic attachment of a receptor functionality - aspects on the mechanism of the Jacobsen-Katsuki epoxidation applied to a supramolecular system

The synthesis of the components of the dynamic supramolecular hydrogen-bonded catalytic system 2 + 3 is described. The catalytic performance and substrate- and enantioselectivity of Mn(salen) catalyst 2 were investigated in the presence and absence of the Zn(porphyrin) receptor unit 3. The effects of pyridine and pyridine N-oxide donor ligands were also studied. Some aspects on the mechanism of th

Comparative genomic hybridization of postirradiation sarcomas

BACKGROUND. Radiotherapy is a known risk factor for sarcoma development. Postirradiation sarcomas arise within the radiation field after a latency period of several years and usually are highly malignant. Very little is yet known about their genetic changes. METHODS. Twenty-seven postirradiation sarcomas were analyzed by comparative genomic hybridization, which allows genome-wide screening of DNA

PID control design and $H_infty$ loop shaping

This paper shows that traditional methods for design of PID controllers can be related to robust H= control. In particular, it shows how the specifications in terms of maximum sensitivity and maximum complementary sensitivity are related to the weighted H= norm introduced by Glover and McFarlane [5]. The paper also shows how to use the Vinnicombe metric to classify those classes of systems which c

Simply invariant subspaces of H2 of some multiply connected regions

The authors are concerned with the invariant subspaces of $H^2(\Omega)$, where $\Omega$ is a bounded, finitely connected, planar domain with an analytic boundary. A subspace of $H^2(\Omega)$ is said to be invariant if it is invariant under multiplication by $z$, and fully invariant if it is invariant under multiplication by all rational functions with poles off the closure of $\Omega$. If $\Omeg

Pulmonary gas exchange is reduced by the cardiovascular diving response in resting humans.

The diving response reduces the pulmonary O(2) uptake in exercising humans, but it has been debated whether this effect is present at rest. Therefore, respiratory and cardiovascular responses were recorded in 16 resting subjects, performing apnea in air and apnea with face immersion in cold water (10 degrees C). Duration of apneas were predetermined to be identical in both conditions (average: 145

Competitive adsorption of a polydisperse polymer during emulsification: Experiments and modeling

In this paper we study the selective adsorption of a high molar mass polymer, OSA-starch, at the cyclohexane/water interface during emulsification. This was made possible through the use of AsFlFFF-MALS-RI which enables us to characterize the size and molar mass of polydisperse ultrahigh molar mass polymers. The results show that the high molar mass components in the molar mass distribution of the

Does tobacco smoking influence the occurrence of hand eczema?

Tobacco smoking is known to influence various inflammatory skin diseases and an association between tobacco smoking and hand eczema has been proposed in some studies. To examine a possible association between reported current tobacco smoking and the occurrence of hand eczema. Previously collected questionnaire data on the occurrence of hand eczema in three occupational cohorts and corresponding co

A population-based study of different antibiotic prescribing in different areas

Background Respiratory tract infections are the most common reason for antibiotic prescription in Sweden as in other countries. The prescription rates vary markedly in different countries, counties and municipalities. The reasons for these variations in prescription rate are not obvious. Aim To find possible explanations for different antibiotic prescription rates in children. Design of study Pros

Predator versus prey: on aerial hunting and escape strategies in birds

Predator and prey attack-escape performance is Likely to be the outcome of an evolutionary arms race, Predatory birds are typically larger than their prey suggesting different flight performances. We analyze three idealized attack-escape situations between predatory and prey birds: climbing flight escape, horizontal speeding, and turning and escape by diving. Generally a smaller bird will outclimb

Ultra-violet absorption cross sections of isotopically substituted nitrous oxide species: (NNO)-N-14-N-14, (NNO)-N-15-N-14, (NNO)-N-14-N-15 and (NNO)-N-15-N-15

The isotopically substituted nitrous oxide species (NNO)-N-14-N-14, (NNO)-N-15-N-14, (NNO)-N-14-N-15 and (NNO)-N-15-N-15 were investigated by ultra-violet (UV) absorption spectroscopy. High precision cross sections were obtained for the wavelength range 181 to 218 nm at temperatures of 233 and 283 K. These data are used to calculate photolytic isotopic fractionation constants as a function of wave

Paleoecology of the Early Permian strata at heimefrontfjella, Dronning Maud Land, Antarctica

Palaeopalynological studies form an integral part of the geological investigation of the Late Paleozoic sedimentary history of Dronning Maud Land. During the examination of organic residues prepared from different localities at Heimefrontfjella, the freshwater green alga Botryococcus was found. Exceptionally well-preserved colonies of Botryococcus were recorded in several samples at two sections o

Molecular basis of cell-biomaterial interaction: Insights gained from transcriptomic and proteomic studies

With the growing interest in clinical interventions that involve medical devices, the role for new biomaterials in modern medicine is currently expanding at a phenomenal rate. Failure of most implant materials stems from an inability to predict and control biological phenomena, such as protein adsorption and cell interaction, resulting in an inappropriate host response to the materials. Contempora

A global Fordian compromise? - and what it would mean for the transition to sustainability

At first, it may seem as if the sustainable transition would force us to make a cynical trade-off between (a) the immediate needs of the global poor and (b) the future needs of the global rich. Crucial objectives, such as climate stability, are commonly held to be unattainable if the rest of the world would come to enjoy present Western living standards. Challenging this pessimistic analysis, this

Concentrations of inorganic elements in 20 municipal waters in Sweden before and after treatment - links to human health

The water chemistry of 20 municipal water treatment plants in southern Sweden, representing various bedrock situations, and water qualities, were investigated. Four water samples, raw and treated. were collected from each plant and analyzed by predominantly ICP-OES and ICP-MS at four occasions from June to December, 2001. The concentrations of Ca, Mg. K.. Na, HCO3 and a number of micronutrients, v

Adipose triglyceride lipase and hormone-sensitive lipase are the major enzymes in adipose tissue triacylglycerol catabolism

The mobilization of free fatty acids from adipose triacylglycerol (TG) stores requires the activities of triacylglycerol lipases. In this study, we demonstrate that adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL) are the major enzymes contributing to TG breakdown in in vitro assays and in organ cultures of murine white adipose tissue (WAT). To differentiate between ATGL- and