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Exposure to persistent organochlorine pollutants and type 2 diabetes mellitus.

Persistent organochlorine pollutants (POPs), such aspolychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), dichloro diphenyl trichloroethane (DDT) and its major metabolite 1,1-dichloro-2,2-bis (p-chlorophenyl)-ethylene (p,p' -DDE) have been associated with type 2 diabetes mellitus (T2DM) in recent epidemiological studies. We have analysed 2,2',4,4',5,5' -hexachlorobiphenyl (C

Experimental excursions on adaptive landscapes: Density-dependent selection on egg size

Theories of density-dependent natural selection suggest that intraspecific competition will favor juveniles of high competitive ability. Empirical evidence has been provided from laboratory selection experiments, but field studies are lacking due to the logistical difficulties of experimentally manipulating population densities in natural settings. Here, we present data from a decade long experime

Direct supercritical fluid extraction of alkylphenols from spiked and wastewater samples using extraction cells equipped with hydrophobic membrane-assemblies

Akylphenols (4-nonylphenol, 4-(1,1,3,3-tetramethylbutyl)-phenol and 2,6-bis(1,1-dimethylethyl)-4-ethylphenol) have been directly extracted from water samples using neat supercritical carbon dioxide and collected on an octadecyl silica (ODS) solid phase trap. The extraction cells were equipped with home-built assemblies containing hydrophobic membranes. The assemblies were inserted at each end of t

Development of analysis tools and stochastic models of road profiles regarding their influence on heavy vehicle fatigue

Road profiles are analyzed with focus on road characteristics essential for heavy vehicle fatigue assessment. Road profile measurements indicate that roads contain short sections with above-average irregularity. Such rough sections are shown to cause most of the vehicle fatigue damage. An algorithm using a spatial-frequency description is developed to automatically identify rough sections. On the

TinyRealTime - An EDF Kernel for the Atmel ATmega8L AVR

This report describes the design and implementation of {TinyRealTime}, an event-based real-time kernel for the Atmel AVR ATmega8L 8-bit micro-controller. The kernel is event-based and supports fully preemptive earliest-deadline-first scheduling of tasks. Semaphores are provided to support task synchronization. The focus of the report is on the memory management, timing, and internal workings of th

Ultrastructure and functional organization of mouthpart sensory setae of the spiny lobster Panulirus argus: New features of putative mechanoreceptors

In comparison with other decapods, the Caribbean spiny lobster Panulirus argus has little diversity in the external morphology of the setae on the mouth apparatus. In mouthpart areas that frequently touch food items only two types of setae can be distinguished: simple setae and cuspidate setae. Simple setae are by far more numerous. The ultrastructural data presented here show that both types of s

Vad ska vi med kunskapsöversikter till?

Forskarna Eva-Malin Antoniusson, Arne Kristiansen, Leili Laanemets, Bengt Svensson och Dolf Tops har granskat skriften Sprututbyte – En genomgång av den internationella forskningen och den svenska debatten (Fri förlag 2005) och menar att det är ett exempel på en starkt politiserad kunskapsöversikt.

C1-TEN is a negative regulator of the Akt/PKB signal transduction pathway and inhibits cell survival, proliferation, and migration

We have previously identified C1 domain-containing phosphatase and TENsin homologue (C1-TEN) as being an intracellular binding partner for Axl receptor tyrosine kinase (RTK). C1-TEN is a tensin-related protein that houses an N-terminal region with predicted structural similarity to PTEN. Here, we report our observations on the effects of ectopic expression of C1-TEN in HEK293 cells, which resulted

Enantioselective formal synthesis of tridemethylisovelleral

A simple and efficient synthetic route to the bicyclic alpha,beta-unsaturated beta-keto ester methyl (3aS,7aS)-6-oxo-2,3,3a,6,7,7ahexahydro-1H-indene-5-carboxylate, a versatile intermediate in the synthesis of biologically active unsaturated 1,4-dialdehydes, is described. The synthesis includes a chirality introducing nonenzymatic asymmetric desymmetrization (ADS) reaction of a cyclic nieso-anhydr

Hormone therapy: Improving therapy decisions and monitoring

Objectives: Due to the increased diagnosis of prostate cancer at earlier stages and the overall increased use of hormone therapy, also in earlier disease stages, many patients will receive long-term hormone therapy. Therefore, the timing of initiating hormone therapy and the type of hormone therapy have become crucial items in the appropriate management of patients with prostate cancer. in additio

Enantioselective synthesis of bridgehead hydroxyl bicyclo[2.2.2]octane derivatives via asymmetric allylindation

A recent new strategy for the transformation of mono-dioxolane protected 1,3-cyclohexadione into bridgehead hydroxyl bicyclo[2.2.2]octane derivatives, based on allylindation followed by ozonolysis and intramolecular aldol addition, was modified to include asymmetric allylindation. This enabled the first enantioselective synthesis of (1R,4R,6S)-endo-4-(tert-butyl-dimethyl-silyloxy)-6-hydroxy-bicycl

Intruder features in the island of inversion: The case of Mg-33

The Na-33 beta decay was studied online using mass separation techniques and a first description of the level structure of the neutron-rich isotope Mg-33, with N=21, has been obtained. The experiment involved the measurement of beta-gamma, beta-gamma-gamma, and beta -n-gamma coincidences as well as neutron spectra by time-of-flight technique. The first low energy level scheme for the daughter nucl

Improved reliability of ultrasonic surveillance of abdominal aortic aneurysms

OBJECTIVES: Small abdominal aortic aneurysms (AAA) are usually managed conservatively by serial ultrasound examinations to assess size. The development of the size of the AAA will determine whether the patient is a candidate for surgery. The precision of measurement is therefore of considerable importance. The aim of this study was to evaluate the accuracy and the reproducibility of a newly develo

Long-term history of land-use and vegetation at Ire, an agriculturally marginal area in Blekinge, south Sweden

Pollen records from a small lake and a small peatland at Ire in northern Blekinge, Sweden, reveal that until A.D. 300 there was a mixed deciduous type of woodland dominated by Quercus, Tilia and Corylus, with Betula, Pinus, Populus, Fraxinus, Ulmus and Acer as important constituents. The first, but weak, signs of human influence on the vegetation are detected around 2300 B.C. At this time, the are

Response to directional light by leaves of a sun-tracking lupine (Lupinus Succulentus)

Experiments were done to examine the phototrophic response of sun-tracking leaves of Lupinus succulentus Dougl. to fixed beams of white and broad band light. Upon irradiation with 15 W m-2 white light that struck the laminae at an angle of 45°, there was a 45–60 min lag period prior to leaf movement. The greatest rate of movement was 15° h-1, and reorientation ceased when leaves attained a positio