Sökresultat

Filtyp

Din sökning på "*" gav 534677 sökträffar

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

Correcting the colour-dipole cascade model with fixed order matrix elements

An algorithm is presented in which the Colour-Dipole Cascade Model as implemented in the Ariadne program is corrected to match the fixed order tree-level matrix elements for e e(+) --> n jets. The result is a full parton level generator for e e(+) annihilation where the generated states are correct on tree-level to fixed order in alpha(s) and to all orders with modified leading logarithmic (MLLA)

Phenotypic and genetic variation in emergence and development time of a trimorphic damselfly

Although colour polymorphisms in adult organisms of many taxa are often adaptive in the context of sexual selection or predation, genetic correlations between colour and other phenotypic traits expressed early in ontogeny could also play an important role in polymorphic systems. We studied phenotypic and genetic variation in development time among female colour morphs in the polymorphic damselfly

Dietary intake of heterocyclic amines in relation to socioeconomic, lifestyle and other dietary factors: estimates in a Swedish population

Objectives: To estimate the dietary intakes of heterocyclic amines (HCAs), to examine the intakes in relation to socio-economics, lifestyle and other dietary factors and to compare the classification of subjects by intake of HCA versus intake of meat and fish. Design: Cross-sectional analysis within the Malmo Diet and Cancer (MDC) cohort. Data were obtained from a modified diet history, a structur

Inverse modelling of thermal conductivity from temperature measurements at the Prototype Repository, Aspo HRL

The Prototype Repository, at the Aspo HRL (Hard Rock Laboratory), is a demonstration project for the deposition of spent nuclear fuel, and provides a full-scale reference for testing predictive models relating to a spent nuclear fuel repository, both its individual components as well as the complete system. The final layout involves six deposition holes, four in an inner section and two in an oute

Sulfur passivation for ohmic contact formation to InAs nanowires

We have studied the formation of ohmic contacts to InAs nanowires by chemical etching and passivation of the contact areas in an ammonium polysulfide, (NH4)(2)S-x, water solution. The nanowires were exposed to different dilution levels of the (NH4)(2)Sx solution before contact metal evaporation. A process based on a highly diluted ( NH4)S-2(x) solution was found to be self-terminating, with minima

Beyond robins: aerodynamic analyses of animal flight.

Recent progress in studies of animal flight mechanics is reviewed. A range of birds, and now bats, has been studied in wind tunnel facilities, revealing an array of wake patterns caused by the beating wings and also by the drag on the body. Nevertheless, the quantitative analysis of these complex wake structures shows a degree of similarity among all the different wake patterns and a close agreeme

Absorption of NO in an alkaline solution of KMnO4

A packed column has been used to study the absorption of nitrogen oxide in an alkaline solution of potassium permanganate. The reactions taking; place during the absorption have been examined and the rate constants have been estimated from experimental data. The experiments show that potassium permanganate is an excellent absorbent for nitrogen oxide. However, to avoid formation of MnO2, the hydro

Evapotranspiration of Artemisia ordosica vegetation in stabilized arid desert dune in Shapotou, China

More than 40 years of revegetation using mainly Artemisia ordosica, Hedysarum scoparium, and Caragana korshinskii at Shapotou Desert Experimental Research Station near Lanzhou has established a dwarf-shrub and herbaceous cover on the stabilized sand dunes. The evapotranspiration (ET) of the xerophyte dwarf-shrub A. ordosica plant vegetation was measured by the autoweighing lysimeter method during

Newborns discriminate novel from harmonic sounds: A study using magnetoencephalography

Objective: We investigated whether newborns respond differently to novel and deviant sounds during quiet sleep. Methods: Twelve healthy neonates were presented with a three-stimulus oddball paradigm, consisting of frequent standard (76%), infrequent deviant (12%), and infrequent novel stimuli (12%). The standards and deviants were counterbalanced between the newborns and consisted of 500 and 750 H

Early Jurassic leech cocoons from eastern Australia

Abstract in UndeterminedA small assemblage of clitellate annelid cocoons (egg cases) is described from the Early Jurassic Marburg Subgroup, Clarence-Moreton Basin, eastern Australia. Two complete specimens are preserved on bedding planes, and numerous fragments were recovered from organic residues prepared for mesofossil analysis. The complete specimens are assigned to Burejospermum Krassilov emen

Gene transfer improves erythroid development in ribosomal protein S19-deficient Diamond-Blackfan anemia.

Diamond-Blackfan anemia (DBA) is a congenital bone marrow failure syndrome characterized by a specific deficiency in erythroid progenitors. Forty percent of the patients are blood transfusion-dependent. Recent reports show that the ribosomal protein S19 (RPS19) gene is mutated in 25% of all patients with DBA. We constructed oncoretroviral vectors containing the RPS19 gene to develop gene therapy f

Effects of tobacco smoke on tumor growth and radiation response of dunning R3327 prostate adenocarcinoma in rats

BACKGROUND: The influence of tobacco smoke has been investigated on the growth rate and histology of prostate cancer, both in untreated tumors and in those subjected to fractionated irradiation. METHODS: Twenty-five rats were implanted bilaterally with Dunning R3327 tumor fragments at 10 weeks of age. Approximately 3 months later, they were randomly allocated to two groups, one of which was expose

COX-2 and p53 in human sinonasal cancer: COX-2 expression is associated with adenocarcinoma histology and wood-dust exposure

The causal role of wood-dust exposure in sinonasal cancer (SNC) has been established in epidemiological studies, but the mechanisms of SNC carcinogenesis are still largely unknown. Increased amounts of COX-2 are found in both premalignant and malignant tissues, and experimental evidence link COX-2 to development of cancer. Many signals that activate COX-2 also induce tumor suppressor p53, a transc

In vitro degradation and in vivo biocompatibility study of a new linear poly(urethane urea)

Segmented poly(urethane urea)s (PUUs) with hard segments derived only from methyl 2,6-diisocyantohexanoate (LDI) without the use of a chain extender have previously been described. These materials, which contain hard segments with multiple urea linkages, show exceptionally high strain capability (1600-4700%). In the study reported here, the rate and effect of hydrolysis of these materials were det

Inhibition of cancer cell growth by crude extract and the phenolics of Terminalia chebula retz. fruit

A 70% methanol extract of Terminalia chebula fruit, was studied for its effects on growth in several malignant cell lines including a human (MCF-7) and mouse (S115) breast cancer cell line, a human osteosarcoma cell line (HOS-1), a human prostate cancer cell line (PC-3) and a non-tumorigenic, immortalized human prostate cell line (PNT1A) using assays for proliferation ([3H]-thymidine incorporation

Long waves and information technologies - on the transition towards the information society

In this paper we argue that Long Wave Theory provides a useful conceptual tool for understanding the transition from the industrial to the, post-industrial economy. While economic theories struggle to fully explain the structural changes involved in the shift towards the information economy, long wave theory offers a promising avenue for understanding the complex relationship between technology an

99mTc-DMSA renal scintigraphy during kidney maturation

A total of 282 renal scintigrams with Tc-99m DMSA in 238 children ranging in age from 10 days to 13 years performed during a 3-year period were reviewed. The authors present 94 kidneys in 85 children in whom no sign of pathology was demonstrated clinically, either by ultrasound or intravenous urography, or by micturating urethrocystography. By exploring homogeneity or heterogeneity of tracer distr