HIV-1 protease has a broad and complex substrate specificity, which hitherto has escaped a simple comprehensive definition. This, and the relatively high mutation rate of the retroviral protease, makes it challenging to design effective protease inhibitors. Several attempts have been made during the last two decades to elucidate the enigmatic cleavage specificity of HIV-1 protease and to predict c

BACKGROUND: Adolescent smokers are often unsuccessful in quitting and difficult to retain in cessation programs. In health promotion, focusing on the right target groups is essential. Aim. The aim was to examine if adolescent occasional smokers differ from daily smokers, and if possible differences could be useful for targeted smoking cessation programs. METHODS: Ninety-one percent of all teenager

Nonlinear exciton relaxation processes, exciton-exciton annihilation, and amplified spontaneous emission were investigated in thin films of ladder-type poly(para-phenylene) under excitation by femtosecond light pulses. Both processes become apparent at similar excitation intensities, however their properties are very different. They cause different exciton relaxation kinetics and their intensity d

Autofluorescence is a nuisance in the field of fluorescence imaging and tomography of exogenous molecular markers in tissue, degrading the quality of the collected data. In this letter, we report autofluorescence insensitive imaging using highly efficient upconverting nanocrystals (NaYF4: Yb3+ /Tm3+) in a tissue phantom illuminated with near- infrared radiation of 85 mW/cm(2). It was found that im

Sprouting of mossy fibres from dentate granule cells occurs in several animal models of epilepsy and in epileptic humans. Mossy fibre sprouting might contribute to epileptogenesis but also could be a compensatory, inhibitory response. We analysed mossy fibre sprouting in the supragranular zone of the dentate gyrus using Timm's histochemical method in genetically fast and slow kindling rats. Before

Kungahälla was the southernmost town in medieval Norway. The site, now in Sweden, is about 2 kmwest of today's Kungälv. Kungahälla occupies a significant place in the oldest written sources, the Norse sagas, where we have a glimpse of the important role that the town played in early medieval Norwegian society. Opinions have been divided as to how far back this role can he taken, but there is no ce

The importance of genetic and environmental variation in condition in shaping evolutionary trade-offs have recently been subject to much theoretical discussion, but is very difficult to investigate empirically in most field-based systems. We present the results from mechanistic experimental manipulations of reproductive investment and condition in two female colour morphs (orange and yellow) of si

Occupational skin diseases are among the most frequent work-related diseases in industrialized countries. Good occupational skin disease statistics exist in few countries. Questionnaire studies are needed to get more data on the epidemiology of occupational skin diseases. The Nordic Occupational Skin Questionnaire Group has developed a new questionnaire tool - Nordic Occupational Skin Questionnair

People tend to forget information that is related to memories they are actively trying to retrieve. On the basis of results from behavioral studies, such retrieval-induced forgetting is held to result from inhibitory control processes that are recruited to attenuate interference caused by competing memory traces. Employing electrophysiological measures of brain activity, the present study examined

High-pressure x-ray powder diffraction has been measured on the half doped rare earth manganite Nd0.5Ca0.5MnO3 up to a pressure of 15 GPa. We report the presence of a quantifiable amount of shear distortion of the MnO6 octahedra in Nd0.5Ca0.5MnO3 at high pressures. The lattice strain of Nd0.5Ca0.5MnO3 is minimal at a crossover pressure of p*similar to 7 GPa, with the same lattice strain above and

Helicobacter pylori (H. pylori), atrophic gastritis, dietary and lifestyle factors have been associated with gastric cancer (GC). These factors have been evaluated in a large case-control study nested in the European Prospective Investigation into Cancer and Nutrition carried out in 9 countries, including the Mediterranean area. Participants, enrolled in 1992-1998, provided life-style and dietary

OBJECTIVES: This study clarified the exposure-response relationships for the organic acid anhydrides (OAA) hexahydrophthalic (HHPA) and methylhexahydrophthalic (MHHPA) anhydrides and the development of specific immunoglobulin (IG) E and G antibodies and work-related symptoms. METHODS: In an epoxy resin-using factory, air levels of OAA were determined by gas chromatography-mass spectrometry. Occupa

The ionization dynamics of Ar and Xe clusters irradiated with intense vacuum ultraviolet light from a free-electron laser is investigated using photoelectron spectroscopy. Clusters comprising between 70 and 900 atoms were irradiated with femtosecond pulses at 95 nm wavelength (similar to 13 eV photon energy) and a peak intensity of similar to 4x10(12) W/cm(2). A broad thermal distribution of emitt

The low-energy region of the intermolecular potential energy hypersurface (PES) of the ammonia dimer was studied at the level of second-order Moller-Plesset perturbation theory (MP2) using a very large basis set. Individual minima were located on the PES employing the counterpoise (CP) correction to account for the basis set superposition error (BSSE). Apart from these canonical MP2 calculations l

The endo-beta-1,4-mannanase from the soil bacterium Cellulomonas fimi is a modular plant cell wall degrading enzyme involved in the hydrolysis of the backbone of mannan, one of the most abundant polysaccharides of the hemicellulosic network in the plant cell wall. The crystal structure of a recombinant truncated endo-beta-1,4-mannanase from C. fimi (CMan26A-50K) was determined by X-ray crystallogr

The development of a mathematical model and a computer program to facilitate the study of the multi-cylinder paper drying process is presented. Experimentally determined values far different heat and mass transfer coefficients are used to ensure the physical validity of the model. A unique feature of the model is its inclusion of a mass transfer coefficient for the dryer fabric. Thus far, the mass