PURPOSE: To evaluate the feasibility of magnetic resonance (MR) perfusion imaging in the human lung to help detect perfusion defects distal to suspected pulmonary embolism. MATERIALS AND METHODS: Seven patients suspected of having pulmonary embolism first underwent ventilation-perfusion lung scintigraphy followed by MR perfusion imaging with rapid acquisition of two sets of dynamic images in the c

A systematic study of the dissolution of dry, polydisperse polyethylene oxide) (PEO) samples, obtained from mixtures of low-molecular-weight and high-molecular-weight PEO, was made. During the dissolution process, the individual release of the low-and high-molecular-weight fractions was monitored. The highmolecular-weight/low-molecular-weight ratio controls the release rate, and the fraction of hi

We present further properties of a previously proposed recursive scheme for parametrization of n-by-n unitary matrices. We show that the factors in the recursive formula may be introduced in any desired order. The method is used to study the invariant phases of unitary matrices. The case of four-by-four unitary matrices is investigated in detail. We also address the question of how to construct sy

We have applied and evaluated system identification methods using both commercial software and dedicated subspace model identification software (MOESP). Results using the different software tools have been similar (but not identical) in accuracy and predictive power, the main differences being the time required for computation and occasional failures of one algorithm in delivery of a stable model.

Molecular interaction between host mucosal surfaces and outer membrane components of microbes is crucial in the infection process. The outer membrane of pathogenic Neisseria contains surface molecules such as pili, PilC, and Opa and a monolayer of lipooligosaccharide (LOS), all of which are involved in the interaction with host cells. Pili mediate the initial attachment to human epithelial cells,

Absorption spectra of a series of cyclic conjugated ketones and thioketones have been computed at the multiconfigurational second-order multistate perturbation level of theory, the CASSCF/MS-CASPT2 method. Excitation energies, transition dipole moments, oscillator strengths, and static dipole moments are reported and discussed for excited states with energies lower than approximate to7-8 eV. The m

We have used the x-ray magnetic circular dichroism technique to characterize ultrathin Co films deposited on flat and vicinal Cu(111) single crystal surfaces. All films were prepared and characterized in situ, in ultrahigh vacuum. Similar to other investigators we report a 40% increase of the ratio m(l)/m(s) (orbital to spin moment) of ultrathin Co on both flat and vicinal Cu(111). In addition, an

We present a method for the measurement of a temperature differential across a single quantum dot that has transmission resonances that are separated in energy by much more than the thermal energy. We determine numerically that the method is accurate to within a few percent across a wide range of parameters. The proposed method measures the temperature of the electrons that enter the quantum dot a

The colonisation intensity and composition of the mycorrhizal community in the aquatic plants Lobelia dortmanna and Littorella uniflora were studied. The mycorrhizal fungi were characterised by fungal specific nested PCR and sequencing using the 5'-end of the LSU rDNA as target. For this, primers for the clade of Acaulospora, the clade including Glomus mosseae and G. intraradices and the clade con

Maternal effects by which females provide their offspring with non-genetic factors such as hormones, nutrients and antibodies can have an important impact on offspring fitness. In vertebrates, maternal antibodies (matAb) are transferred from the mother, via the placenta, egg yolk or milk during lactation to offspring until they are 2 weeks (birds), 4-10 weeks (rodents) and 9 months (humans) old, r

Alcohols, such as 2,2,2-trifluoroethanol (TFE), have been shown to induce a cooperative transition to an open helical structure in many proteins, but the underlying molecular mechanism has not been identified. Here, we employ the technique of magnetic relaxation dispersion (MRD) to study the TFE-induced transition of -lactoglobulin at pH 2.4. Unlike traditional techniques that focus on protein sec

The "Coordination Action" ProDaC (Proteomics Data Collection) - funded by the EU within the 6(th) framework programme - was created to support the dissemination, utilization and publication of proteomics data. Within this international consortium, standards are developed and maintained to support extensive data collection by the proteomics community. An important part of ProDaC are workshops organ

Plastic wave propagation is studied during progressive plastic buckling of elastic viscoplastic slabs. The numerical results of the buckling behaviour are studied using two recent approaches for monitoring the plastic wave propagation. One method is a direct geometrical monitoring of the waves using a sequence of smooth approximations (geo-plot). The other method is a contour plot method (q-plot)

To study the associations between intake of various types of fat and risk of prostate cancer (PCa) in a population-based cohort. We have studied 10,564 initially cancer-free men of the Malmo Diet and Cancer cohort, aged 45-73 years. Diet was assessed by a modified diet history method. Cases and clinical characteristics were ascertained via national and regional registry data. During a mean follow-

BACKGROUND: Individuals with chronic depression respond poorly to both medication and psychotherapy. The reasons for the poorer response, however, remain unclear. One potential factor is the presence of comorbid Axis II personality disorders (PDs), which occur at high rates among these patients. METHODS: This study examines the moderating influence of co-occurring PDs, primarily in cluster C, amon

We present a general model study of surface-enhanced resonant Raman scattering and fluorescence focusing on the interplay between electromagnetic effects and the molecular dynamics. Our model molecule is placed close to two Ag nanoparticles and has two electronic levels. A Franck-Condon mechanism provides electron-vibration coupling. Using realistic parameter values for the molecule we find that a

Trichoderma reesei produces five known endoglucanases. The most studied are Cel7B (EG I) and Cel5A (EG II) which are the most abundant of the endoglucanases. We have performed a characterisation of the enzymatic properties of the less well-studied endoglucanases Cel12A (EG III), Cel45A (EG V) and the catalytic core of Cel45A. For comparison, Cel5A and Cel7B were included in the study. Adsorption s

The purpose of this study was to investigate the combustion characteristics of soot deposits from diesel-powered engines. The soot deposits were collected in the exhaust stream from diesel engines at Volvo Truck Corporation in Gothenburg, Sweden. The combustion experiments were performed in a flow reactor in the presence of 2–10% O2 and 0 or 7% H2O. The temperature was increased at a rate of 10°C/

The quasi-linear Maxwell equations describing electromagnetic wave propagation in nonlinear media permit several weak solutions, which may be discontinuous (shock waves). It is often conjectured that the solutions are unique if they satisfy an additional entropy condition. The entropy condition states that the energy contained in the electromagnetic fields is irreversibly dissipated to other energ