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Quantification of low-velocity motion using a navigator-echo supported MR velocity-mapping technique: application to intracranial dynamics in volunteers and patients with brain tumours

Gradient-echo pulse sequences with velocity-encoding gradients of 22.5-25 mT/m, were used for brain-motion and CSF-flow studies. To reduce motion artifacts, a phase-correction technique based on navigator echoes was evaluated. Three patients with right-sided parietal tumours were investigated; one astrocytoma grade III-IV, one astrocytoma grade I-II and one benign meningioma. In healthy volunteers

Associations between autoantibodies against apolipoprotein B-100 peptides and vascular complications in patients with type 2 diabetes.

AIMS/HYPOTHESIS: Oxidation of LDL in the arterial extracellular matrix is a key event in the development of atherosclerosis and autoantibodies against oxidised LDL antigens reflect disease severity and the risk of developing acute cardiovascular events. Since type 2 diabetes is associated with increased oxidative stress, we tested the hypothesis that autoantibodies against oxidised LDL antigens ar

Protective effect of low molecular weight heparin on experimental colitis: role of neutrophil recruitment and TNF-alpha production.

OBJECTIVE: The purpose of this study was to examine the impact and mechanism of action of low molecular weight heparin (LMWH) in a model of murine colitis. MATERIALS AND METHODS: Balb/c mice were exposed to 5% dextran sodium sulfate (DSS) in the drinking water for five days. LMWH (500 units/kg/day) was administered by subcutaneous injection prior to and throughout the treatment period with DSS. Cl

The hedging performance of electricity futures on the Nordic power exchange

The Nordic Power Exchange (Nord Pool), the first multinational exchange for electricity trading, has existed since January 1996. Spot and futures contracts are traded on this exchange and its typical characteristics are very high volatilities as well as non-normally distributed returns. This article looks at electricity futures and how they can be used for short-term hedging of positions taken in

Upper Pleistocene stratigraphy at the Medininkai site, eastern Lithuania: a continuous record of the Eemian-Weichselian sequence

Eemian-Weichselian sequences, located outside the maximum limit of the Late Weichselian ice sheet, provide excellent opportunities for the discovery of continuous sedimentary records encompassing the whole Last Interglacial/Glacial cycle. Such a sequence is recorded in a borehole (117P) through the succession in a small kettlehole lake located at Medininkai, eastern Lithuania. The succession consi

Magnetic compass of migratory Savannah sparrows is calibrated by skylight polarizarion and sunrise and sunset

Migratory birds use compass systems derived from the geomagnetic field, the stars, the sun and polarized light patterns. We tested whether birds use a single underlying reference system for calibration of these compasses and, specifically, whether sunset and sunrise polarized light cues from the region of the sky near the horizon are used to calibrate the magnetic compass. We carried out orientati

Detecting violations of sensory expectancies following cerebellar degeneration:

Two hypotheses concerning cerebellar function and predictive behavior are the sensory prediction hypothesis and the timing hypothesis. The former postulates that the cerebellum is critical in generating expectancies regarding forthcoming sensory information. The latter postulates that this structure is critical in generating expectancies that are precisely timed; for example, the expected duration

A study of estimation method for conduction band offset in semiconductor heterostructure by using triple-barrier resonant tunneling diodes

A method for evaluating a band offset of a heterojunction is proposed by measuring temperature dependence of current-voltage (I-V) characteristics in triple-barrier resonant tunneling diodes (TBRTDs). The method was applied for investigating a conduction band offset by using GaAs0.25P0.75/GaAs TBRTDs with thin strain heterobarriers grown by MOCVD and DeltaE(c) was estimated as 200-240 meV. In the

Abnormal urethral motor function is common in female stress, mixed, and urge incontinence.

Aim: To investigate the urethral motor function in incontinent women. Materials and Methods: The intraurethral pressure was measured continuously in the high-pressure zone of the urethra at rest and during repeated short squeezes around the microtip transducer catheter in a group of 205 women with clinically manifest urinary incontinence (severe), and compared with the findings of investigations i

This beauty should drink well for 10-12 years: A note on recommendations as semantic middles

This paper capitalizes on the types of portrayal of the event in recommendations of prime drinking time using data from wine tasting notes. It argues that the weakly deontic nature of recommendation fosters semantic middles, not only the middle construction proper such as This beauty should drink well for 10–12 years, but recommendation as such is characterized by a mid-degree of transfer of actio

Variational second-order Moller-Plesset theory based on the Luttinger-Ward functional

In recent years there have been some rather successful applications of a new variational technique for calculating the total energies of electronic systems. The new method is based on many-body perturbation theory and uses the one-electron Green function as the basic "variable" rather than the wave function of traditional variational calculations. It is the purpose of the present work to promote t

Buffer medium exchange in continuous cell and particle streams using ultrasonic standing wave focusing

A microfluidic strategy to perform buffer exchange of particle and cell suspensions in a continuous flow format on, chip is presented. Ultrasonic standing wave technology is utilized to confine particulate matter to the centre of a buffer exchange channel while particle free buffer is sequentially aspirated via capillaries that branch off from the buffer exchange channel. At each such branch, clea

Process-based estimates of terrestrial ecosystem isoprene emissions: incorporating the effects of a direct CO2-isoprene interaction

In recent years evidence has emerged that the amount of isoprene emitted from a leaf is affected by the CO2 growth environment. Many - though not all - laboratory experiments indicate that emissions increase significantly at below-ambient CO2 concentrations and decrease when concentrations are raised to above-ambient. A small number of process-based leaf isoprene emission models can reproduce this

Total heart volume variation throughout the cardiac cycle in man.

Variations in total heart volume (atria plus ventricles) during a cardiac cycle affect efficiency of cardiac pumping. The goals of this study were to confirm the presence, extent, and contributors of total heart volume variation during the cardiac cycle in healthy volunteers with the use of MRI. Eight healthy volunteers were examined by MRI at rest. Changes in total cardiac volume throughout the c

Apolipoproteins A-I and B in obese children

Body mass index (BMI), the distribution of fat, birth weight, physical fitness, apolipoproteins (apo) A-I and B, total cholesterol (TC), and high-density lipoprotein cholesterol (HDLC) were studied in 38 obese 10- to 11-year-olds in comparison to 52 age-matched controls. Obese children had higher concentration of apo B and a lower apo A-I:B ratio. Significant correlations were found between (a) ap

Including indigestible carbohydrates in the evening meal of healthy subjects improves glucose tolerance, lowers inflammatory markers, and increases satiety after a subsequent standardized breakfast.

Low-glycemic index (GI) foods and foods rich in whole grain are associated with reduced risk of type 2 diabetes and cardiovascular disease. We studied the effect of cereal-based bread evening meals (50 g available starch), varying in GI and content of indigestible carbohydrates, on glucose tolerance and related variables after a subsequent standardized breakfast in healthy subjects (n = 15). At br

Effect of set-up uncertainties on the dose distribution in the match region of supraclavicular and tangential breast fields

BACKGROUND: The objective of this paper is to illustrate the effect of a gap of 5 mm, an overlap of 5 mm and a perfect match on the dose distribution across the junction of tangential breast fields and adjacent supraclavicular and axillary fields. MATERIALS AND METHODS: For this purpose film dosimetry was applied to measure relative dose distributions in two sagittal planes in an anthropomorphic b

The influence of N load and harvest intensity on the risk of P limitation in Swedish forest soils

Nitrogen (N) is often considered to be the major factor limiting tree growth in northern forest ecosystems. An increased N availability, however, increases the demand for other nutrients such as base cations and phosphorous (P) which in turn may change which nutrient is the limiting factor. If P or base cations become limiting, N will start to leach which means a risk of increased eutrophication o