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Modal analysis of living spruce using a combined Prony and DFT multichannel method for detection of internal decay

Modal analysis is a widely accepted tool for non-destructive evaluation of mechanical properties of materials and structures. In this paper, a partial modal analysis is used to examine whether internal decay in living trees can be detected by studying the resonance frequencies of the trees. We examine the resonance frequencies of living spruce of species Picea abies (Norway spruce) by means of the

Exposure to beta-carbolines norharman and harman

The aromatic beta-carbolines norharman and harman have been implicated in a number of human diseases including Parkinson's disease, tremor, addiction and cancer. It has been shown that these compounds are normal body constituents formed endogenously but external sources have been identified. Here, we summarise literature data on levels of norharman and harman in fried meat and fish, meat extracts,

Forces Controlling the Rate of DNA Ejection from Page λ

The goal of this work was to investigate how internal and external forces acting on DNA affect the rate of genome ejection from bacteriophage λ after the ejection is triggered in vitro by a λ receptor. The rate of ejection was measured with time-resolved static and dynamic light scattering, while varying such parameters as temperature and packaged DNA length, as well as adding DNA-binding proteins

Transcriptional responses of Paxillus involutus and Betula pendula during formation of ectomycorrhizal root tissue

In order to obtain information on genes specifically expressed in the ectomycorrhizal symbiosis, 3,555 expressed sequence tags (ESTs) were analyzed from a cDNA library constructed from ectomycorrhiza formed between the basidiomycete Paxillus involutus and birch (Betula pendula). cDNA libraries from saprophytically growing fungus (3,964 ESTs) and from axenic plants (2,532 ESTs) were analyzed in par

Enterally but not parenterally administered Phaseolus vulgaris lectin induces growth and precocious maturation of the gut in suckling rats

Background: The lectin, phytohemagglutinin (PHA) has been shown to induce growth and functional maturation of the gastrointestinal (GI) tract in suckling rats. Objectives: To investigate the effect of the administration route, and whether enteral exposure to PHA was necessary to induce functional maturation. Methods: Fourteen-day-old rats were daily administered PHA via orogastric feeding (0.05 mg

Haem-delivery proteins in cytochrome c maturation System II

P>Cytochromes of the c-type function on the outer side of the cytoplasmic membrane in bacteria where they also are assembled from apo-cytochrome polypeptide and haem. Two distinctly different systems for cytochrome c maturation are found in bacteria. System I present in Escherichia coli has eight to nine different Ccm proteins. System II is found in Bacillus subtilis and comprises four proteins: C

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