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A controlled comparison of myelography, computed tomography, and magnetic resonance imaging in clinically suspected lumbar disc herniation

STUDY DESIGN. A controlled prospective blinded study. OBJECTIVES. To compare the diagnostic power of myelography, computed tomography and magnetic resonance imaging in the diagnosis of low lumbar disc herniation. METHODS. Eighty patients with monoradicular sciatica were examined by myelography, computed tomography, and magnetic resonance imaging, and all underwent subsequent surgery. The images we

Ultrafast singlet energy transfer competes with intersystem crossing in a multi-center transition metal polypyridine complex

Transition metal polypyridine complexes are finding widespread applications within many areas of chemistry. For their light-induced processes, the generally accepted picture is that all function emanates from triplet states because the singlet states initially prepared by light absorption are depopulated via intersystem crossing on the 100-fs time scale, before they are significantly involved in c

Stochastic model for the investigation of the influence of turbulent mixing on engine knock

A stochastic model based on a probability density function (PDF) was developed for the investigation of different conditions that determine knock in spark ignition (SI) engine, with focus on the turbulent mixing. The model used is based on a two-zone approach, where the burned and unburned gases are described as stochastic reactors. By using a stochastic ensemble to represent the PDF of the scalar

Abnormal mechanical properties of the aorta in Marfan's syndrome

OBJECTIVES: Aortic dilatation, dissection and rupture are among the major causes of death in subjects with Marfan's syndrome. The aim of the study was to investigate the mechanical properties or compliance of the aorta in these subjects and compare them with a healthy age- and sex-matched reference population. MATERIALS AND METHODS: An ultrasound phase-locked echo-tracking system was used to deter

Tänkande bakom val och användning av livsmedel : Faktorer som medverkar till eller utgör hinder för förändring av matvanor i hälsofrämjande riktning

Popular AbstractAvhandlingsarbetet fokuserar tänkande och handlande i förhållande till livsmedel som pedagogiska förutsättningar för förståelse av kostbudskap och näringsrekommendationer.Studiens syfte var att undersöka och beskriva hur tidigare erfarenheter framträder i människors tänkande och handlande i förhållande till deras val och användning av fettrika resp. kostfiberrika livsmedel för att For educational purposes, research has been proposed on the circumstances and facts which govern eating habits and the intake of nutrients. By focusing on the perspective of the individual, this study explores and describes how previous experiences influence people's thinking and acting in relation to their present eating habits to elucidate factors that contribute to, or hinder, changes for the p

Influence of shear rate on the flux during ultrafiltration of colloidal substances

The shear rate at the surface of a membrane has a distinct influence on the membrane flux in systems containing colloidal substances. If the shear rate is decreased, flux decreases since the thickness of the boundary layer of retained solutes at the membrane surface then increases. When low molecular solutes are used, flux increases again when the shear rate is increased. However, if large solutes

Low-lying unoccupied electronic states in 3d transition-metal fluorides probed by NEXAFS at the F 1s threshold

The near-edge x-ray absorption fine structure (NEXAFS) at the F 1s threshold has been studied with high-energy resolution for a series of binary fluorides, including KF, TiF4, VF4, VF3, CrF3, CrF2, MnF3, MnF2, FeF3, FeF2, CoF2, NiF2, CuF2, and ZnF2 as well as for SF6 in the gas phase, and for the PF6- and TiF62- molecular anions of the solid compounds KPF6 and K2TiF6. Most of these spectra were me

Asbestos, cement, and cancer in the right part of the colon

OBJECTIVE--The aim was to investigate associations between exposure to mineral fibres and dust, and cancer in subsites within the large bowel. DESIGN--Pooled retrospective cohort studies. SUBJECTS AND SETTINGS--Blue collar workers, employed for at least one year in different trades; asbestos cement or cement workers (n = 2507), other industrial workers (n = 3965), and fishermen (n = 8092). MAIN OU

The morphogenesis of intention and structural stability of motifs.

This article is based on the Agent-action-Objective (AaO) axiom and assumes that intention can be discovered and made evident. But this requirement can be satisfied only under the condition that a particular individual can be identified with his style of writing. This implies that the nature of writing becomes approachable. Getting a style under control presupposes the A-component, which is discus

Ultramicrobiosensor for the selective detection of glutamate

Carbon fiber microelectrodes, able to detect catecholamine release from single cells, have significantly contributed to our present understanding of the mechanism of secretory neurotransmission. In spite of their obvious advantages, there are only a few amperometric sensors (characterized by appropriate size, sensitivity, and selectivity) able to measure the release of other (not easily oxidizable

Statistics for chemistry students - how to make a statistics course useful by focusing on applications

By putting emphasis on applications in two basic statistics courses for chemistry students and chemical engineering students we have enhanced student motivation and increased student activity. In addition to a traditional in-class exam, the students complete a take-home project where statistical problems relevant to chemists are discussed. We give several examples of the course and project materia

Renal angioplasty causes a rapid transient increase in inflammatory biornarkers, but reduced levels of interleukin-6 and endothelin-1 1 month after intervention

Objective To examine prospectively whether inflammatory biomarkers and endothelin (ET)-1 are increased in patients with renal artery stenosis (RAS), and to investigate how treatment with percutaneous transluminal renal angioplasty (PTRA) affects these variables during the first month after intervention. Methods One hundred patients with suspected RAS undergoing renal angiography were included. PTR

Subjective versus interviewer assessment of global quality of life among persons with schizophrenia living in the community: A Nordic multicentre study

Background: Few studies have investigated differences between subjective and externally assessed quality of life in individuals with a severe mental illness. In a sample of 387 patients with schizophrenia living in the community the present study investigated the association between subjective and interviewer-rated quality of life, clinical and sociodemographic factors related to the two assessmen

A novel electrical property of three-terminal ballistic junctions and its applications in nanoelectronics

A room-temperature electrical property of three-terminal ballistic junctions (TBJs) is predicted. For a symmetric TBJ. it is shown that when finite voltages F and -V are applied to the left and right branches. the voltage Output V, from the central branch will always be negative. This characteristic appears even when the symmetry in the TBJ is broken. provided that V! is larger than a threshold. A