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Fast and accurate numerical solution to an elastostatic problem involving ten thousand randomly oriented cracks

An algorithm is presented for the multiple crack problem in planar linear elastostatics. The algorithm has three important properties: it is stable, it is adaptive, and its complexity is linear. This means that high accuracy can be achieved and that large-scale problems can be treated. In a numerical example stress fields are accurately computed in a mechanically loaded material containing 10,000

Quantitative diffusion coefficient maps using fast spin-echo MRI

In this work, we have evaluated the performance of a diffusion-sensitive fast spin-echo (FSE) pulse sequence. The proposed pulse sequence utilises velocity-compensating diffusion-encoding gradients and includes the collection of navigator echoes. Spoiler gradients were inserted in the slice-selecting direction to minimise effects from stimulated echoes. Calculations of the b values showed that cro

Pharmacologic perspective on the physiology of the lower urinary tract.

Myogenic activity, distention of the detrusor, and signals from the urothelium may initiate voiding. In the bladder, afferent nerves have been identified not only in the detrusor, but also suburothelially, where they. form a plexus that lies immediately beneath the epithelial lining. Extracellular adenosine triphosphate (ATP) has been found to mediate excitation of small-diameter sensory neurons v

Soda lime temperatures during low-flow sevoflurane anaesthesia and differences in dead-space.

BACKGROUND: Sevoflurane degrades during low-flow anaesthesia to compound A, and high carbon dioxide absorbent temperatures cause increased degradation. The purpose of this investigation was to determine if larger tidal volumes, without increasing alveolar ventilation, decrease the temperature in the carbon dioxide absorber during low- and minimal-flow sevoflurane anaesthesia. METHODS: Prospective,

Magneto-Optical Measurements of the Pigments in Fully Active Photosystem II Core Complexes from Plants

Preparation of a minimum PSII core complex from spinach is described, containing four Mn per reaction center (RC) and exhibiting high O2 evolving activity [~4000 mol of O2 (mg of chl)-1 h-1]. The complex consists of the CP47 and CP43 chlorophyll binding proteins, the RC D1/D2 pair, the cytochrome b559 subunits, and the Mn-stabilizing psbO (33 kDa) protein, all present in the same stoichiometric am

Dual-broadband rotational CARS modelling of nitrogen at pressures up to 9 MPa. II. Rotational Raman line widths

Rotational coherent anti-Stokes Raman spectroscopy (CARS) is a well-established spectroscopic technique for thermometry at pre-combustion temperatures an atmospheric pressure. However, at pressures of several MPa, a previous investigation revealed large discrepancies between experimental data and the theoretical model. A re-evaluation has been made of these data (at room temperature and in the ran

Chemical kinetic modeling of combustion in internal combustion engines using reduced chemistry

A general method for automatically reducing detailed kinetic mechanisms for complex fuels is applied. The method is based on the simultaneous use of sensitivity, reaction-flow, and extended lifetime analyses. The sensitivity analysis detects species to which the overall combustion process is sensitive. Small inaccuracies in calculating these species result in large errors in the characteristic beh

Lung tissue eosinophils may be cleared through luminal entry rather than apoptosis: effects of steroid treatment

Spontaneous or steroid-induced eosinophil apoptosis occurring in vitro has not been demonstrated in lung tissues in vivo. This study examines cell apoptosis in rat lungs using the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP) nick end labeling (TUNEL) technique and transmission electron microscopy (TEM). After establishing sustained lung edema and eosinophilia by

A revision of the North American lichen genus Ahtiana.

The formerly monotypic genus Ahtiana (type species: A. sphaerosporella (Müll. Arg.) Goward is shown to include two additional species, A. aurescens (Tuck.) Thell & Randl. and A. pallidula (Riddle) Goward & Thell. All three species are endemic to North America, and are characterized by their greenish yellow upper surface, globose ascospores, and caperatic acid in the medulla. The habitat ec

Select comorbid personality disorders and the treatment of chronic depression with nefazodone, targeted psychotherapy, or their combination.

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

Influence of polydispersity on the micellization of triblock copolymers investigated by pulsed field gradient nuclear magnetic resonance

The molecular motion in water of the poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer with the nominal composition EO97PO68EO97 (F127) was investigated with the aid of pulsed field gradient nuclear magnetic resonance (PFG NMR). The signal decays in the PFG experiments have been recorded for 1 wt % F127 in the temperature range from 288 to 313 K and in the concentr

Real-time imaging through optical fiber array-assisted laser-induced fluorescence of capillary electrophoretic enantiomer separations

An advanced detection system based on laser-induced fluorescence imaging for capillary electrophoresis (CE) is presented. An optical fiber array was constructed for collection and transportation of the emitted fluorescent light to the charge-coupled device (CCD) camera. The fiber array makes the setup compact compared with a setup where the capillary is imaged through a camera objective. The imagi

Single InP/GaInP quantum dots studied by scanning tunneling microscopy and scanning tunneling microscopy induced luminescence

We have studied the optical and structural properties of single, self-assembled InP quantum dots (QDs) overgrown with nominally 5 nm of GaInP, using an ultrahigh-vacuum scanning tunneling microscope (STM) operating at low temperatures. The STM is combined with an optical detection system, which allows us to detect the emission from individual quantum dots with high spatial resolution. We find that

Statistical inference for a class of modified power series distributions with applications to random mapping theory

We investigate a class of discrete distributions generated by expanding a parametric function in a Lagrange series. There is a close relationship to the class of generalized Poisson distributions, and special cases of our class of distributions arise in the context of random mapping theory. Unbiased estimation is discussed and the results are applied to inference problems in connection with two ra

Proshchenkoite-(Y) from Russia - a new mineral species in the vicanite group: descriptive data and crystal structure

A REE-bearing fluorosilicate from the Tommot REE-Nb deposit in Yakutia, Russia, described without a name in 1966, is characterized here as a new species, proshchenkoite-(Y), of the vicanite group of borosilicates. Wavelength-dispersive electron probe analyses gave the following empirical formula: (Y3.70REE7.54Ca1.55Na1.16Mn0.77Th0.10Pb0.01)(Sigma 14.83)(Fe0.832+M0.15Ti0.02)(Sigma 1.00)Ca-1.00 (P0.

Unified treatment of fluorescence and Raman scattering processes near metal surfaces

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

Recent improvement in outcome of unrelated donor transplantation for aplastic anemia

The aim was to determine whether outcome of unrelated donor transplantation for severe aplastic anemia has improved in recent years and whether this is due to patient selection or better transplant technology. We analyzed 498 patients transplanted during 1990-2005. By running univariate regression models dichotomizing year of transplantation we defined 1998 as the year of the most significant chan

Multi-language translation and cross-cultural adaptation of the OARSI/OMERACT measure of intermittent and constant osteoarthritis pain (ICOAP)

Aim: To conduct a multi-language translation and cross-cultural adaptation of the Intermittent and Constant OsteoArthritis Pain (ICOAP) questionnaire for hip and knee osteoarthritis (OA). Methods: The questionnaires were translated and cross-culturally adapted in parallel, using a common protocol, into the following languages: Czech, Dutch, French (France), German, Italian, Norwegian, Spanish (Cas