Growth Analysis of Pulsed Laser Ablated Films

The spontaneous organization on a substrate of nanoparticles (NPs) nucleated in a laser-generated plasma results in self-assembling due to both direct specific interactions and to indirect ambient-mediated ones. A number of well-differentiated film morphologies are observed, from isolated NPs to percolated island structures. The distribution of the width of gaps between NPs, or islands formed upon NP coalescence in two representative percolated Au films, is lognormal, indicating that the growth process is random. A finer inspection of similar surface morphologies allows to correlate regularity in gap sizes and surface coverage to differences in film performance as substrates for surface-enhanced Raman spectroscopy.     

Genomic structure of the human ezrin gene

The ERM proteins, ezrin, radixin, and moesin, act as linkers between the plasma membrane and actin cytoskeleton. They are involved in a variety of cellular functions, such as cell adhesion, migration, and the organization of cell surface structures, and are highly homologous, both in protein sequence and in functional activity, with merlin/schwannomin, a neurofibromatosis-2-associated tumor-suppressor protein. We report here the genomic structure and intron junction sequences of the human ezrin gene. Ezrin consists of 13 exons and spans approximately 24 kb genomic DNA. The coding parts of the exons range in size from 12 bp to 275 bp and the introns from 182 bp to 7 kb. The genomic structures of ezrin and moesin are highly conserved, suggesting their recent divergence. Radiation hybrid mapping has refined the location of ezrin to the interval between D6S442 and D6S281. Received: 1 June 1998 / Accepted: 25 August 1998     

Fatty Chains of Different Lipid Classes of Semliki Forest Virus and Host Cell Membranes

Semliki Forest virus was grown in BHK-21 cells. The major classes of phospho-and glycolipids of the virus were analyzed for the compositions of fatty acids, aldehydes, and sphingosine bases, and the major glycerophospholipids were analyzed for the relative proportions of alkenyl-acyl, alkyl-acyl, and diacyl forms. All viral lipid classes proved to be mixtures of several molecular species. Each class contained a characteristic mixture of fatty chains, which was different in all other classes. All viral lipid classes resembled their counterparts of the host plasma membrane and also those of the endoplasmic reticulum. The gangliosides of the virus and the plasma membrane proved to be similar even at the level of individual molecular species. The number of certain lipid molecules in an average virion was less than the number of the protein molecules.     

Partial migration in roe deer: migratory and resident tactics are end points of a behavioural gradient determined by ecological factors

Ungulate populations exhibiting partial migration present a unique opportunity to explore the causes of the general phenomenon of migration. The European roe deer Capreolus capreolus is particularly suited for such studies due to a wide distribution range and a high level of ecological plasticity. In this study we undertook a comparative analysis of roe deer GPS location data from a representative set of European ecosystems available within the EURODEER collaborative project. We aimed at evaluating the ecological factors affecting migration tactic (i.e. occurrence) and pattern (i.e. timing, residence time, number of migratory trips). Migration occurrence varied between and within populations and depended on winter severity and topographic variability. Spring migrations were highly synchronous, while the timing of autumn migrations varied widely between regions, individuals and sexes. Overall, roe deer were faithful to their summer ranges, especially males. In the absence of extreme and predictable winter conditions, roe deer seemed to migrate opportunistically, in response to a tradeoff between the costs of residence in spatially separated ranges and the costs of migratory movements. Animals performed numerous trips between winter and summer ranges which depended on factors influencing the costs of movement such as between‐range distance, slope and habitat openness. Our results support the idea that migration encompasses a behavioural continuum, with one‐trip migration and residence as its end points, while commuting and multi‐trip migration with short residence times in seasonal ranges are intermediate tactics. We believe that a full understanding of the variation in tactics of temporal separation in habitat use will provide important insights on migration and the factors that influence its prevalence.     

From deception to frankness： Benefits of ontogenetic shift in the anti-predator strategy of alder moth Acronicta alni larvae

Animals can avoid predation by masquerading as objects that are not food to their predators. Alder moth Acronicta alni larvae go through an impressive ontogenetic change from masquerade to highly conspicuous appearance： early larval stages resemble bird droppings but in the last instar the larval coloration changes into striking yellow-and-black stripes. We hypothe- sized that such a change may be driven by differential predation favoring dissimilar anti-predator strategies in different life stages We show with a series of laboratory assays that larvae are distasteful to birds regardless of their developmental stage, suggesting that ontogenetic color change is not driven by the differential chemical defense. Birds showed higher variance in hesitation to- ward conspicuous prey; some individuals hesitated long time before attacking whereas all birds attacked instantly masqueraded prey. We also found that the activity level of the larvae increased with age, which fits to the fact that larvae need to move from foliage to pupation sites. In the field by using artificial larvae resembling the two life-history stages we found predation risk to vary during the season： In early summer larger yellow-and-black larvae were attacked most, whereas later in the summer small ＇bird-dropping-larvae＇ suffered the highest predation. We conclude that the ontogenetic switch from masquerading to aposema- tism is adaptive most likely because actively moving prey cannot mimic immotile objects and thus, aposematism during the ac- tive and vulnerable period when larvae are searching for pupation sites becomes beneficial     

Leisure-Time Physical Activity and All-Cause Mortality

Background

Physical inactivity is a major public health problem associated with increased mortality risk. It is, however, poorly understood whether vigorous physical activity is more beneficial for reducing mortality risk than activities of lower intensity. The aim of this study was to examine associations of the intensity and volume of leisure-time physical activity with all-cause mortality among middle-aged women and men while considering sociodemographic and health related factors as covariates.

Methods

Questionnaire survey data collected in 2000-02 among 40–60-year-old employees of the City of Helsinki (N = 8960) were linked with register data on mortality (74% gave permission to the linkage) providing a mean follow-up time of 12-years. The analysis included 6429 respondents (79% women). The participants were classified into three groups according to intensity of physical activity: low moderate, high moderate and vigorous. The volume of physical activity was classified into three groups according to tertiles. Cox regression analysis was used to calculate hazard ratios (HR) and 95% confidence intervals (CIs) for all-cause mortality.

Results

During the follow up 205 participants died. Leisure-time physical activity was associated with reduced risk of mortality. After adjusting for covariates the vigorous group (HR = 0.54, 95% CI 0.34–0.86) showed a reduced risk of mortality compared with the low moderate group whereas for the high moderate group the reductions in mortality risk (HR = 0.72, 95% CI 0.48–1.08) were less clear. Adjusting for the volume of physical activity did not affect the point estimates. Higher volume of leisure-time physical activity was also associated with reduced mortality risk; however, adjusting for the covariates and the intensity of physical activity explained the differences.

Conclusions

For healthy middle-aged women and men who engage in some physical activity vigorous exercise may provide further health benefits preventing premature deaths.     

Enzymatic synthesis of two lacto-N-neohexaose-related Lewis x heptasaccharides and their separation by chromatography on

Radiolabelled lacto-N-neohexaosc was fucosylated with partiallypurified     

Single mid-chain GlcNAcβ1-6Galβ1-4R sequences of linear oligosaccharides are resistant to endo-β-galactosidase ofBacteroides fragilis

Endo--galactosidase (EC 3.2.1.103) ofBacteroides fragilis, at 250 mU ml^–1, did not cleave the internal galactosidic linkage of the linear radiolabelled trisaccharide GlcNAc1-6Gal1-4GlcNAc, or those of the tetrasaccharides Gal1-4GlcNAc1-6Gal1-4GlcNAc and Gal1-4GlcNAc1-6Gal1-4Glc. The isomeric glycans which contained the GlcNAc1-3Gal1-4GlcNAc/Glc sequence were readily cleaved.Abbreviations GlcNAc 2-acetamido-2-deoxy-d-glucose - Lact lactose - MT maltotriose - MTet maltotetraose - R _MTet chromatographic migration rate in relation to that of maltotetraose     

Enhanced activity of hyperthermostable Pyrococcus horikoshii endoglucanase in superbase ionic liquids

Biotechnology Letters - Ionic liquids (ILs) that dissolve biomass are harmful to the enzymes that degrade lignocellulose. Enzyme hyperthermostability promotes a tolerance to ILs. Therefore, the...