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Strong Tendency (strong + tendency)
Selected AbstractsChaperone-like activities of different molecular forms of ,-casein.BIOPOLYMERS, Issue 8 2009Importance of polarity of N-terminal hydrophilic domain Abstract As a member of intrinsically unstructured protein family, ,-casein (,-CN) contains relatively high amount of prolyl residues, adopts noncompact and flexible structure and exhibits chaperone-like activity in vitro. Like many chaperones, native ,-CN does not contain cysteinyl residues and exhibits strong tendencies for self-association. The chaperone-like activities of three recombinant ,-CNs wild type (WT) ,-CN, C4 ,-CN (with cysteinyl residue in position 4) and C208 ,-CN (with cysteinyl residue in position 208), expressed and purified from E. coli, which, consequently, lack the phosphorylated residues, were examined and compared with that of native ,-CN using insulin and alcohol dehydrogenase as target/substrate proteins. The dimers (,-CND) of C4-,-CN and C208 ,-CN were also studied and their chaperone-like activities were compared with those of their monomeric forms. Lacking phosphorylation, WT ,-CN, C208 ,-CN, C4 ,-CN and C4 ,-CND exhibited significantly lower chaperone-like activities than native ,-CN. Dimerization of C208 ,-CN with two distal hydrophilic domains considerably improved its chaperone-like activity in comparison with its monomeric form. The obtained results demonstrate the significant role played by the polar contributions of phosphorylated residues and N-terminal hydrophilic domain as important functional elements in enhancing the chaperone-like activity of native ,-CN. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 623,632, 2009. This article was originally published online as an accepted preprint. The "Published Online" date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com [source] Fungivore host-use groups from cluster analysis: patterns of utilisation of fungal fruiting bodies by ciid beetlesECOLOGICAL ENTOMOLOGY, Issue 6 2005Glenda M. Orledge Abstract., 1.,Ciid beetles typically live and breed in the fruiting bodies of lignicolous basidiomycete fungi. This study was undertaken to address the lack of an objective examination of patterns of host use by ciids. 2.,Cluster analysis of ciid host-use datasets from Britain, Germany, North America, and Japan, and subsequent cross-dataset comparisons, demonstrated the existence of ciid host-use patterns of wide geographical occurrence. These patterns were formalised as ciid host-use groups. 3.,Six Holarctic ciid host-use groups, and two host-use subgroups, were identified, and are described. Each host-use group comprises an assemblage of fungal genera and the breeding ciids that it supports. Each taxon belongs to only a single host-use group, but may be associated with several members of that group. There is a strong tendency for closely related taxa to belong to the same host-use group. 4.,It is suggested that ciid host-use groups are defined ultimately by host chemistry, with the ciids that belong to a particular group recognising, and responding positively to, emitted volatiles characterising the fungi belonging to that group. 5.,The idea of the host-use group bears comparison with the concepts of niche and guild, but is not equivalent to either. 6.,Ciid host-use groups have a valuable role to play in underpinning future studies of ciid ecology, also the systematics of both ciids and their fungal hosts. [source] Strategic Political Participation and RedistributionECONOMICS & POLITICS, Issue 1 2002Toke Skovsgaard Aidt The purpose of this paper is to study formation of support and opposition to redistribution. We analyze a society with two groups of citizens and a government. The government distributes income from one group to the other in response to political pressure. The interaction between the groups is modeled as a two-stage game. In stage 1, the groups decide if they want to be politically active. In stage 2, the active group or groups seek influence on the direction and size of the transfer. We demonstrate that supporters of redistribution are always politically active but that opposition is often absent. Moreover, when opposition is absent there is a strong tendency for underdissipation of the transfer, while political competition typically leads to overdissipation. [source] Temporal distribution of clinical seizures over the 24-h day: A retrospective observational study in a tertiary epilepsy clinicEPILEPSIA, Issue 9 2009Wytske A. Hofstra Summary Purpose:, Very few studies have evaluated seizure occurrence in humans over the 24-h day; data from children are particularly scarce. Circadian patterns in seizure occurrence may be of importance in epilepsy research and may have important implications in diagnosis and therapy. Methods:, We have analyzed clinical seizures of 176 consecutive patients (76 children, 100 adults) who had continuous electroencephalography (EEG) and video monitoring lasting more than 22 h. Several aspects of seizures were noted, including classification, time of day, origin, and sleep stage. Results:, More than 800 seizures were recorded. Significantly more seizures were observed from 11:00 to 17:00 h, and from 23:00 to 05:00 h significantly fewer seizures were seen. The daytime peak incidences were observed in seizures overall, complex partial seizures (in children and adults), seizures of extratemporal origin (in children), and seizures of temporal origin (in adults). Incidences significantly lower than expected were seen in the period 23:00 to 05:00 h in seizures overall, complex partial seizures (in children and adults), and in tonic seizures (in children). In addition, significantly fewer seizures of temporal (in children and adults) and extratemporal origin (in children) were observed in this period. Discussion:, The results suggest that certain types of seizures have a strong tendency to occur in true diurnal patterns. These patterns are characterized by a peak during midday and a low in the early night. [source] Distress, Dissociation, and Embodied Experience: Reconsidering the Pathways to Mediumship and Mental HealthETHOS, Issue 1 2005REBECCA SELIGMAN This article explores the biocultural bases of spirit possession mediumship in the Afro-Brazilian religion, Candomblé. After a brief review of the literature, the article moves beyond the biomedical and social-structural explanations that have dominated the theoretical landscape, by attempting to construct an etiology of mediumship that is traced through the interface of individual characteristics with the cultural belief system that forms their context. Data were collected from a total of 71 individuals over the course of a year-long field study in Salvador, Brazil. Analyses of social ethnography, life history and semistructured interviews along with results from psychological inventories, suggest that altered states of consciousness should not be considered the central and defining element of mediumship. An alternative model is proposed, in which the combination of social conditions and somatic susceptibilities causes certain individuals to identify with the mediumship role, and predisposes them to dissociate. However in the context of Candomblé, dissociation is not a pathological experience, but rather a therapeutic mechanism, learned through religious participation, that benefits individuals with a strong tendency to somatize. [source] Thin Film Solar Cells: Materials Science at InterfacesADVANCED ENGINEERING MATERIALS, Issue 10 2005J. Fritsche Abstract Interfaces are important for the efficiencies of thin film solar cells. In particular for polycrystalline chalcogenide semiconductors as Cu(In,Ga)(S,Se)2 and CdTe the existing physical concepts, which describe the electronic properties of semiconductor interfaces, are not sufficient. The increased complexity is mostly due to the non-abruptness of the interfaces and the strong tendency for the formation of defects. For the CdTe thin film solar cell a very relevant interface for their operation and efficiency is the CdTe/CdS semiconductor hetero junction. The properties of the semiconductor interfaces have been characterised systematically with photoelectron spectroscopy (XPS/UPS) in integrated ultra high vacuum (UHV) systems for sample preparation and analysis. Withal the key topic is the experimental determination of the band alignment at the semiconductor interfaces. For high efficiency CdTe solar cell production CdCl2 activation is of major importance. The effects of the CdCl2 treatment step on CdTe solar cells had been not completely understood so far. To investigate its influence the activation process has been transferred into the integrated UHV system. We will report about chemical and electronic modifications of the CdTe/CdS hetero interface due to in-situ CdCl2 activation performing sputter depth profiles in combination with X-ray photoelectron spectroscopy (XPS). [source] Analysis of Nanostructuring in High Figure-of-Merit Ag1,xPbmSbTe2+m Thermoelectric MaterialsADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Bruce A. Cook Abstract Thermoelectric materials based on quaternary compounds Ag1,xPbmSbTe2+m exhibit high dimensionless figure-of-merit values, ranging from 1.5 to 1.7 at 700,K. The primary factor contributing to the high figure of merit is a low lattice thermal conductivity, achieved through nanostructuring during melt solidification. As a consequence of nucleation and growth of a second phase, coherent nanoscale inclusions form throughout the material, which are believed to result in scattering of acoustic phonons while causing only minimal scattering of charge carriers. Here, characterization of the nanosized inclusions in Ag0.53Pb18Sb1.2Te20 that shows a strong tendency for crystallographic orientation along the {001} planes, with a high degree of lattice strain at the interface, consistent with a coherent interfacial boundary is reported. The inclusions are enriched in Ag relative to the matrix, and seem to adopt a cubic, 96 atom per unit cell Ag2Te phase based on the Ti2Ni type structure. In-situ high-temperature synchrotron radiation diffraction studies indicated that the inclusions remain thermally stable to at least 800,K. [source] The behavior of extreme cold air outbreaks under greenhouse warmingINTERNATIONAL JOURNAL OF CLIMATOLOGY, Issue 9 2006S. Vavrus Abstract Climate model output is used to analyze the behavior of extreme cold-air outbreaks (CAOs) under recent and future climatic conditions. The study uses daily output from seven GCMs run under late-twentieth century and projected twenty-first century radiative conditions (SRES A1B greenhouse gas emission scenario). We define a CAO as an occurrence of two or more consecutive days during which the local mean daily surface air temperature is at least two standard deviations below the local wintertime mean temperature. In agreement with observations, the models generally simulate modern CAOs most frequently over western North America and Europe and least commonly over the Arctic. These favored regions for CAOs are located downstream from preferred locations of atmospheric blocking. Future projections indicate that CAOs,defined with respect to late-twentieth century climatic conditions,will decline in frequency by 50 to 100% in most of the Northern Hemisphere during the twenty-first century. Certain regions, however, show relatively small changes and others actually experience more CAOs in the future, due to atmospheric circulation changes and internal variability that counter the thermodynamic tendency from greenhouse forcing. These areas generally experience greater near-surface wind flow from the north or the continent during the twenty-first century and/or are especially prone to atmospheric blocking events. Simulated reductions in CAOs are smallest in western North America, the North Atlantic, and in southern regions of Europe and Asia. The Eurasian pattern is driven by a strong tendency for the models to produce sea-level pressure (SLP) increases in the vicinity of the Mediterranean Sea (intermodel mean of 3 hPa), causing greater advection of continental air from northern and central Asia, while the muted change over western North America is due to enhanced ridging along the west coast and the increased frequency of blocking events. The North Atlantic response is consistent with a slowdown of the thermohaline circulation, which either damps the warming regionally or results in a cooler mean climate in the vicinity of Greenland. Copyright © 2006 Royal Meteorological Society. [source] Intravesical instillation therapy with bacillus Calmette-Guérin for superficial bladder cancer: Study of the mechanism of bacillus Calmette-Guérin immunotherapyINTERNATIONAL JOURNAL OF UROLOGY, Issue 2 2007Yasuyo Shintani Aim: In order to clarify the initial step of the mechanism by which bacillus Calmette-Guérin (BCG) exhibits antitumor activity via the immune response induced in the bladder submucosa after intravesical BCG therapy for human bladder cancer, various cytokines secreted in the urine after BCG instillation were measured. Methods: After transurethral resection of bladder cancer, a 6-week course of BCG instillation was performed. At the first and sixth weeks' dosings, spontaneously excreted urine was collected before and 4, 8, and 24 h after BCG instillation. The urinary cytokines were determined by Sandwich enzyme-linked immunosorbent assay using monoclonal antibodies against granulocyte,macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-,, granulocyte colony-stimulating factor (G-CSF), interleukin (IL)-1,, IL-8, interferon (IFN)-,, and IL-12. Results: After the BCG therapy, various cytokines, such as GM-CSF, TNF-,, G-CSF, IL-1,, IL-8, IFN-,, and IL-12 were secreted, comprising the immune response cascade. The mean urinary excretions of GM-CSF and TNF-, 4 h after the sixth week's instillation were significantly higher than the pre-instillation levels. There were no significant increases in the urinary IFN-, or IL-12 levels between 4 and 24 h after the sixth week's instillation. The TNF-, level 4 h after the sixth week's instillation had a strong tendency towards the absence of recurrence, with a mean follow-up of 54.1 months. The Kaplan-Meier curve showed the 2, 5, and 10-year recurrence-free survival rates were 72.4%, 65.8%, and 56.4%, respectively. Conclusions: We suggested that the urinary levels of TNF-, might be essential in antitumor activity after BCG therapy and might play an important role in the prevention of bladder tumor recurrence. [source] Effectiveness of cutaneous warming systems on temperature control: meta-analysisJOURNAL OF ADVANCED NURSING, Issue 6 2010Cristina Maria Galvão galvão c.m., liang y. & clark a.m. (2010) Effectiveness of cutaneous warming systems on temperature control: meta-analysis. Journal of Advanced Nursing,66(6), 1196,1206. Abstract Title.,Effectiveness of cutaneous warming systems on temperature control: meta-analysis. Aim., This paper is a report of a meta-analysis to identify the effectiveness of different types of cutaneous warming systems in temperature control for patients undergoing elective surgery. Background., Hypothermia is a common and serious complication of surgery. Different cutaneous warming systems are used to prevent hypothermia during surgery but there have been no previous meta-analyses of the effectiveness of different warming systems in controlling temperature. Data sources., We conducted a search of the CINAHL (2000 to April 2009), Medline (2000 to April 2009), Embase (2000 to April 2009) and the Cochrane Register of Controlled Trials (2000 to April 2009) databases for randomized controlled trials published in English, Spanish and Portuguese. The primary outcome measure of interest was core body temperature. Methods., A systematic review incorporating meta-analysis was carried out. Results., From 329 papers, 23 trials compared warming systems. Forced-air warming systems had a strong tendency towards superior temperature control over passive insulation via cotton blankets (mean difference: 0·29°C; 95% confidence interval: ,0·02 to 0·59, three trials 292 patients) and radiant warming systems (mean difference: 0·16°C; 95% confidence interval: ,0·01 to 0·33, three trials, 161 patients). However, circulating water garments tended to be more effective than forced-air warming systems (mean difference: ,0·73°C; 95% confidence interval: ,1·51 to 0·05, I2 = 97%; four trials, 198 patients). Pooled results approached statistical significance and indicated clinically meaningful differences in temperature control. Conclusion., Current evidence suggests that circulating water garments offer better temperature control than forced-air warming systems, and both are more effective than passive warming devices. [source] Physicochemical characterization of carrageenans,A critical reinvestigationJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Gisela Berth Abstract Kappa-, iota-, and lambda-carrageenan (food grade) were analyzed by static light scattering (MALS in batch mode) in 0.1M NaNO3 at 25 and 60°C, earlier heated up to 90°C or not. At 25°C, there was a strong tendency for a concentration-dependent aggregation in the order lambda < kappa < iota. At 60°C, all samples were molecularly dispersed. The strongly temperature-dependent refractive index increments (equilibrium dialysis) differ. Data interpretation in terms of the wormlike chain model using the Skolnik-Odijk-Fixman approach led to an intrinsic persistence length around 3 to 4 nm and expansion factors as high as 1.5 and above in a thermodynamically good solvent for all three types. Triple-detector HPSEC (DRI, MALS, viscometry) on the three commercial samples plus a degraded (by acidic hydrolysis) kappa-carrageenan in the same solvent/eluant at 60°C yielded a uniform and slightly curved [,]- M relationship for 5 × 103 , M/(g mol) , 3 × 106 and a nearly identical molar mass dependence of the radius of gyration. HPSEC at 25°C on kappa-carrageenan confirmed formation of soluble aggregates. Special emphasis was put on analytical and methodological aspects. The reliability of the experimental data was demonstrated by analogous measurements on dextran calibration standards. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Counting elephants in Montane forests: some sources of errorAFRICAN JOURNAL OF ECOLOGY, Issue 2 2009Hilde Vanleeuwe Abstract The dung count method is widely used to estimate elephant numbers in forests. It was developed in the lowland forests of Central Africa but it is also used in Montane forests in eastern Africa. Using data collected on Mount Kenya and computer simulations, this paper explores the following issues associated with dung surveys in Montane forests: ,,High rainfall at 3000 m altitude on Mount Kenya was expected to accelerate dung pile decay but no significant difference was found between 3000 and 2500 m where less rain falls, possibly because high rainfall at 3000 m is counteracted by lower temperatures; ,,Physical obstacles make it difficult to walk long, straight transects in Montane forests. Deviating from a straight line pushes the distribution of distance measurements from dung piles to the transect centre line (pdist) towards a negative exponential (NE), which complicates data analysis and may give inaccurate estimates. Using short transects largely alleviate this problem; ,,Analysis of dung count simulations shows that the expected sightability curve of pdist pushes towards a NE with increasing numbers of obstacles blocking the view, even along perfectly straight transects; ,,Extrapolating measured dung density to map area on Mount Kenya resulted in an underestimate of c. 13%. An unstratified correction of map area to ground area for Montane areas would be biased because of the strong tendency for elephants to avoid steeply sloping areas. Résumé La méthode par comptage des crottes est largement utilisée pour estimer le nombre des éléphants en forêt. Elle a été mise au point dans les forêts de basse altitude d'Afrique centrale, mais elle est aussi employée dans les forêts de montagne d'Afrique de l'Est. Utilisant les données collectées sur le Mont Kenya et des simulations informatiques, cet article explore les questions suivantes liées au comptage des crottes dans les forêts de montagne: ,,Les fortes chutes de pluies à 3 000 mètres d'altitude sur le Mont Kenya étaient censées accélérer la décomposition des tas de crottes, mais on n'a pas trouvé de différence significative entre 3 000 et 2 500 mètres où il tombe moins de pluie, peut-être parce que les fortes pluies à 3 000 mètres sont compensées par de plus basses températures; ,,Les obstacles physiques rendent plus difficiles de marcher le long de transects rectilignes dans les forêts de montagne. Le fait de dévier de la ligne droite pousse la distribution des mesures des distances entre les tas de crottes et la ligne droite du transect (pdist) vers un modèle exponentiel négatif (EN) qui complique l'analyse des données et peut donner des estimations inexactes. Le fait de recourir à des transects courts réduit considérablement ce problème; ,,L'analyse des simulations de comptages de crottes montre que la courbe de visibilité attendue de pdist pousse vers un EN lorsque le nombre d'obstacles bloquant la vue augmente, même le long de transects parfaitement rectilignes; ,,L'extrapolation de la densité mesurée des crottes sur une carte du Mont Kenya a abouti à une sous-estimation d'environ 13%. Une correction non stratifiée de la surface cartographiée des zones montagneuses vers une surface plane serait biaisée étant donné que les éléphants ont fortement tendance àéviter les zones escarpées et glissantes. [source] Nanocoating hybrid polymer films on large quantities of cohesive nanoparticles by molecular layer depositionAICHE JOURNAL, Issue 4 2009Xinhua Liang Abstract The conformal coating of ultra-thin aluminum alkoxide (alucone) polymer films on primary silica and titania nanoparticles using molecular layer deposition (MLD) in a fluidized bed reactor from 100 to 160 °C is described. In situ mass spectrometry revealed that the growth of alucone MLD films was self-limiting as a function of the individual trimethylaluminum and ethylene glycol exposures. The composition and highly conformal alucone films throughout the surface of both silica and titania nanoparticles were confirmed. The highest growth rate was observed at the lowest sample temperature. Primary nanoparticles were coated individually despite their strong tendency to aggregate during fluidization. Based on the results of chemical and thermogravimetric analysis, the value of x in the formula of Al(OCH2CH2O)x was estimated to be 1.9. The calculated film density slightly increased from 2.0 ± 0.1 to 2.2 ± 0.1 g/cm3 with the increasing of temperature from 100 to 160 °C. © 2009 American Institute of Chemical Engineers AIChE J, 2009 [source] Serum carbohydrate antigen elevations in endometrial adenocarcinomas: Characterization of DU-PAN-2 expression as a tumor markerJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 1 2004Masanori Yasuda Abstract Aim:, To characterize serum elevations of carbohydrate antigens; DU-PAN-2, CA19-9, sialyl Lewisx and CA125 in endometrial adenocarcinomas (EMACs), particularly focusing on the clarification of DU-PAN-2 expression profiles. Methods:, Sixty-four resected EMACs of endometrioid type were used. The preoperative serum values of four markers were measured and comparatively analyzed regarding the relationship between histological grade and clinicopathological stage. Results:, The overall ratios of positive cases were 26.2% for DU-PAN-2, 25.0% for CA19-9, 13.6% for sialyl Lewisx, and 35.5% for CA125. DU-PAN-2 decreased as the grading went up (G1: 410.3 ± 243.8 to G3: 246.7 ± 90.0 U/mL), however, the reverse was true with CA19-9 (G1: 123.9 ± 147.4 to G3: 320.0 ± 180.0 U/mL). Sialyl Lewisx showed a strong tendency towards high elevation in G1 (346.3 ± 102.6 U/mL), compared to G3 (<2.5 U/mL). CA125 increased markedly as the grading went up (G1: 43.5 ± 6.3 to G3: 578.0 ± 10.0 U/mL). During staging-up from I + II to III + IV, the positive ratios inclined in all four markers as follows: DU-PAN-2, 18.4,53.3%; CA19-9, 20.4,40.0%; sialyl Lewisx, 11.4,22.2%; CA125, 31.8,44.4%. Serum elevations and positive ratios were correlated for DU-PAN-2, CA19-9 and CA125, while the reverse relationship was found for sialyl Lewisx. Conclusion:, It is suggested that DU-PAN-2 tends to be produced more in well-differentiated components of EMACs than in poorly differentiated ones. Since approximately half the cases with EMAC were serologically positive for DU-PAN-2 in stage III + IV, the marker is believed to be of much use for monitoring the cases with an extrauterine extent. [source] Local Response to the Global Challenge: Comparing Local Economic Development Policies in a Regional ContextJOURNAL OF URBAN AFFAIRS, Issue 4 2000Joanne Wolfson This article reports on a study that examined and compared the responses of six Greater Toronto Area (GTA) municipalities (two central, four suburban) to the challenges of global economic change. The study was carried out in a context characterized by the transfer to municipal governments of both administrative and financial responsibilities for local services by the government of the Province of Ontario. It found a strong tendency for the municipalities to compete with each other for economic advantage, despite efforts to convince them of the need for a cooperative region-wide approach. Suburban governments relied principally on strategies to draw businesses away from the core, and this type of activity seemed likely to increase because of the municipalities' increased dependence on local property taxes. Nonetheless, study findings suggested several ways in which regional organizations or senior governments might help to strengthen regional economies without expecting municipal governments to surrender control over economic development policy. [source] Biodegradable Nanogels Prepared by Self-Assembly of Poly(L- lactide)-Grafted Dextran: Entrapment and Release of ProteinsMACROMOLECULAR BIOSCIENCE, Issue 11 2008Koji Nagahama Abstract We showed previously that poly(L- lactide)-grafted dextran could form biodegradable nanogels in water. In this paper, various properties of Dex -g- PLLA nanogels were compared with Dex-Chol (dextran-cholesterol conjugate) nanogels to investigate the effects of hydrophobic units. Dex -g- PLLA nanogels exhibited significantly lower CAC and higher colloidal stability, indicating a strong tendency to form nanogels. We prepared lysozyme-loaded Dex -g- PLLA nanogels, and they exhibited a sustained release of lysozyme for 1 week without denaturation in PBS at 37,°C. The Dex -g- PLLA nanogels therefore have great potential as a delivery vehicle for therapeutic protein. [source] Synthesis of Conducting Polymer Spiral Nanostructures Using a Surfactant Crystallite TemplateMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 11 2009Yong Wang Abstract The present work describes, for the first time, the synthesis of spiral nanostructures of conducting polymers by chemical oxidant polymerization using a hydrated surfactant (sodium dodecyl sulfonate (SDSn)) crystallite template. A spiral dislocation structure on the surface of a hydrated SDSn crystallite has been observed and is responsible for the growth of the spiral nanoarchitecture of conducting polymers (polypyrrole, polyaniline). Ammonium peroxydisulfate (APS) has a strong tendency to induce the formation of a spiral dislocation structure of hydrated SDSn crystallites. The mechanism of adsorption of pyrrole or aniline oligomers on the steps of dislocation is proposed for the growth of conducting polymer spirals. [source] Synthesis and characterization of semifluorinated polymers and block copolymersMACROMOLECULAR SYMPOSIA, Issue 1 2003Doris Pospiech Abstract The goal of the investigation presented here was to evaluate the influence of semifluorinated side chains on the bulk structure and the surface properties of polysulfones with different chain structure. Thus, segmented block copolymers consisting of polysulfone and semifluorinated aromatic polyester segments as well as polysulfones having semifluorinated side chains randomly distributed over the polymer backbone were synthesized and characterized. Oxydecylperfluorodecyl side chains were used because of their strong tendency for self-organization. The influence of the chain architecture on the self-organization as well as on the surface properties, particularly the wetting behavior, was examined. It could be shown that despite of the higher self-organizing tendency of block copolymers the surface properties of both polymer types are comparable and depend only on the concentration of side chains. [source] Imaging and spectroscopy of ultrasteep spectrum radio sources,MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2007Carlos G. Bornancini ABSTRACT We present a sample of 40 ultrasteep spectrum (USS; ,,, 1.3, S,,,,) radio sources selected from the Westerbork in the Southern Hemisphere (WISH) catalogue. The USS sources have been imaged in K band at the Cerro Tololo Inter-American Observatory (CTIO) and with the Very Large Telescope (VLT) at Cerro Paranal. We also present VLT, Keck and William Herschel Telescope (WHT) optical spectroscopy of 14 targets selection from four different USS samples. For 12 sources, we have been able to determine the redshifts, including four new radio galaxies at z > 3. We find that most of our USS sources have predominantly small (<6 arcsec) radio sizes and faint magnitudes (K, 18). The mean K -band counterpart magnitude is . The expected redshift distribution estimated using the Hubble K,z diagram has a mean of , which is higher than the predicted redshift obtained for the Sydney University Molonglo Sky Survey,NRAO VLA Sky Survey (SUMSS,NVSS) sample and the expected redshift obtained in the 6C** survey. The compact USS sample analysed here may contain a higher fraction of galaxies which are high redshift and/or are heavily obscured by dust. Using the 74, 352 and 1400 MHz flux densities of a subsample, we construct a radio colour,colour diagram. We find that all but one of our USS sources have a strong tendency to flatten below 352 MHz. We also find that the highest redshift source from this paper (at z= 3.84) does not show evidence for spectral flattening down to 151 MHz. This suggests that very low frequency selected USS samples will likely be more efficient to find high redshift galaxies. [source] Assessment of Fetal Rhythm in Complete Congenital Heart Block by MagnetocardiographyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2000RONALD T. WAKAI We report high precision assessment of fetal rhythm in utero in a case of isolated congenital complete heart block using fetal magnetocardiography. The recordings reveal a remarkably strong tendency for the atria and ventricles to synchronize, which is manifested by the continual presence of ventriculophasic sinus arrhythmia and frequent episodes of accrochage and isorhythmic AV dissociation. [source] Mixed coordination and time-resolved luminescence of lead impurity centresPHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 1 2005K. Polák Abstract The optical properties of Pb2+ -doped K(Cl,Br) and K(Cl,I) mixed crystals were investigated to learn how a mixed surroundings influence mainly emission characteristics of lead impurity centres. In the first case, the emission spectrum changes step-by-step from the chloride to the bromide limit while corresponding lifetimes show some new features. In the second case, the continuity is affected by very low solid-state solubility and a strong tendency to foreign phase creation in stored crystals was observed. Nevertheless, some evidence of mixed lead coordination was found. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Distribution of Adult Male and Female Baccharis concinna (Asteraceae) in the Rupestrian Fields of Serra Do Cipó, BrazilPLANT BIOLOGY, Issue 1 2002A. R. Marques Abstract: This study focuses on the sex ratio and spatial distribution of males and females in three populations of the endemic and restricted tropical dioecious shrub, Baccharis concinna (Asteraceae) in the mountainous region of Serra do Cipó, southeastern Brazil. The proportion of female plants in the population at lower elevation (1000 m a.s.l.) was significantly greater than of male plants. At this elevation of P/N and Ca/Al ratios in the soil were also greater indicating better nutritional status of the soils. The concentration of aluminium increased significantly with the elevation (p < 0.001), perhaps rendering soils less conducive to female plants at higher elevations. Female plants are possibly adversely affected to a greater extent by soil quality than male plants. The spatial distribution of the populations within habitat was tested by the K(t) function, where the neighbourhood of a given individual was defined by a circle with a radius (t) up to 3 m. Despite the strong tendency for aggregation, the distribution of the sexes within habitats was random and the hypothesis was not supported. The independent distribution of the sexes within habitats may be explained by nutrient homogeneity of the soils, as well as by an absence of antagonism between the sexes. Nevertheless, we found a trend for males and females to be aggregated according to their gender. [source] Selecting explanatory variables with the modified version of the Bayesian information criterionQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 6 2008gorzata Bogdan Abstract We consider the situation in which a large database needs to be analyzed to identify a few important predictors of a given quantitative response variable. There is a lot of evidence that in this case classical model selection criteria, such as the Akaike information criterion or the Bayesian information criterion (BIC), have a strong tendency to overestimate the number of regressors. In our earlier papers, we developed the modified version of BIC (mBIC), which enables the incorporation of prior knowledge on a number of regressors and prevents overestimation. In this article, we review earlier results on mBIC and discuss the relationship of this criterion to the well-known Bonferroni correction for multiple testing and the Bayes oracle, which minimizes the expected costs of inference. We use computer simulations and a real data analysis to illustrate the performance of the original mBIC and its rank version, which is designed to deal with data that contain some outlying observations. Copyright © 2008 John Wiley & Sons, Ltd. [source] Identification of heat-induced degradation products from purified betanin, phyllocactin and hylocerenin by high-performance liquid chromatography/electrospray ionization mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2005Kirsten M. Herbach Betanin, phyllocactin (malonylbetanin) and hylocerenin (3-hydroxy-3-methylglutarylbetanin) were isolated from purple pitaya (Hylocereus polyrhizus [Weber] Britton & Rose) juice, and their degradation products generated by heating at 85°C were subsequently monitored by high-performance liquid chromatography/electrospray ionization tandem mass spectrometry. Thermal degradation of phyllocactin and hylocerenin in purified solution excluding the alleged protective effects by the juice matrix is reported for the first time. Betanin was predominantly degraded by hydrolytic cleavage, while decarboxylation and dehydrogenation were of minor relevance. In contrast, hylocerenin showed a strong tendency to decarboxylation and dehydrogenation, hydrolytic cleavage of the aldimine bond occurring secondarily. Phyllocactin degradation was most complex because of additional decarboxylation of the malonic acid moiety as well as generation and subsequent degradation of betanin due to phyllocactin demalonylation. Upon prolonged heating, all betacyanins under observation formed degradation products characterized by an additional double bond at C2C3. Hydrolytic cleavage of the aldimine bond of phyllocactin and hylocerenin yielded previously unknown acylated cyclo -dopa derivatives traceable by positive ionization, while application of ESI(,) facilitated the detection of a glycosylated aminopropanal derivative and dopamine, which have never been described before as betanin degradation products. Copyright © 2005 John Wiley & Sons, Ltd. [source] Poly[dimethyldiphenylphosphonium [di-,4 -iodido-tetra-,3 -iodido-pentacopper(I)]]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 8 2010Ehsan Jalilian The title compound, {(C14H16P)[Cu5I6]}n, prepared from the reaction between copper powder, iodine and dimethyldiphenylphosphonium iodide in hydroxyacetone, features an anion that consists of a continuous two-dimensional Cu,I sheet [Cu,I = 2.5960,(14),2.6994,(13),Å and Cu,I,Cu = 63.28,(5),114.25,(5)°]. The cation, which lies on a mirror plane, is a typical dimethyldiphenylphosphonium ion. The structure shows a strong tendency towards segregation of the inorganic and organic parts of the structure into separate subspaces. The two-dimensional Cu,I sheet displays a pronounced subcell with pseudo-tetragonal symmetry that is broken by ordered vacancies on the Cu position. The symmetry is further reduced by the orientation of the interleaved organic counter-ion that is inclined with respect to the pseudo-mirror planes defined by the Cu,I sheet normal, perpendicular to the b axis. [source] Length variability and interspersion patterns of the HRAS1 minisatellite: a new approach for the reconstruction of human population relationshipsANNALS OF HUMAN GENETICS, Issue 4 2001A. VEGA During recent years the HRAS1 minisatellite has been analysed by several authors because of its putative association with cancer susceptibility. The aim of this report is to test the usefulness of this minisatellite in investigating human population relationships. We have studied 370 chromosomes from two well-differentiated populations: Galicia (North-west Iberia) and South-east Africa, as well as available data on allele length gene frequencies. The fragment analysis results show a strong tendency to differentiate between non-African and African populations. In spite of the usefulness of fragment analysis, the minisatellite variant repeat (MVR) approach of the HRAS1 minisatellite appears to be a more powerful method for use in human population studies, due to the high level of diversity of its interspersion pattern structures. In addition, this approach has allowed us to define some new structural characteristics of this minisatellite. Four different major groups of human HRAS1 minisatellite alleles could be distinguished following a structural criterion based on the MVR code. Furthermore, the characterisation of the HRAS1 minisatellite in chimpanzees revealed clear differences when compared to humans, not only with respect to the allele size but also to the internal structure. [source] High cortical spreading depression susceptibility and migraine-associated symptoms in Cav2.1 S218L miceANNALS OF NEUROLOGY, Issue 1 2010Arn M. J. M. van den Maagdenberg PhD Objective The CACNA1A gene encodes the pore-forming subunit of neuronal CaV2.1 Ca2+ channels. In patients, the S218L CACNA1A mutation causes a dramatic hemiplegic migraine syndrome that is associated with ataxia, seizures, and severe, sometimes fatal, brain edema often triggered by only a mild head trauma. Methods We introduced the S218L mutation into the mouse Cacna1a gene and studied the mechanisms for the S218L syndrome by analyzing the phenotypic, molecular, and electrophysiological consequences. Results Cacna1aS218L mice faithfully mimic the associated clinical features of the human S218L syndrome. S218L neurons exhibit a gene dosage,dependent negative shift in voltage dependence of CaV2.1 channel activation, resulting in enhanced neurotransmitter release at the neuromuscular junction. Cacna1aS218L mice also display an exquisite sensitivity to cortical spreading depression (CSD), with a vastly reduced triggering threshold, an increased propagation velocity, and frequently multiple CSD events after a single stimulus. In contrast, mice bearing the R192Q CACNA1A mutation, which in humans causes a milder form of hemiplegic migraine, typically exhibit only a single CSD event after one triggering stimulus. Interpretation The particularly low CSD threshold and the strong tendency to respond with multiple CSD events make the S218L cortex highly vulnerable to weak stimuli and may provide a mechanistic basis for the dramatic phenotype seen in S218L mice and patients. Thus, the S218L mouse model may prove a valuable tool to further elucidate mechanisms underlying migraine, seizures, ataxia, and trauma-triggered cerebral edema. ANN NEUROL 2010;67:85,98 [source] Powder study of poly[(,2 -2,2-dimethylpropane-1,3-diyl diisocyanide)-,2 -iodido-silver(I)]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 3 2009Mwaffak Rukiah In order to explore the chemistry of the bidentate ligand 2,2-dimethylpropane-1,3-diyl diisocyanide and to investigate the effect of counter-ions on the polymeric structure of (2,2-dimethylpropane-1,3-diyl diisocyanide)silver(I) complexes, the title polymeric compound, [AgI(C7H10N2)]n, was synthesized by treatment of 2,2-dimethylpropane-1,3-diyl diisocyanide with AgI. X-ray powder diffraction studies show, as expected, a polymeric structure, similar to the very recently reported Cl, and NO3, analogues [AgX(C7H10N2)]n (X = Cl, or NO3,). In the title structure, the AgI centre is bridged to two adjacent AgI neighbours by bidentate 2,2-dimethylpropane-1,3-diyl diisocyanide ligands via the NC groups to form [Ag{CNCH2C(CH3)2CH2NC}]n chains. The iodide counter-ions crosslink the AgI centres of the chains to form a two-dimensional polymeric {[Ag{CNCH2C(CH3)2CH2NC}]I}n network. This study also shows that this bidentate ligand forms similar polymeric structures on treatment with AgX, regardless of the nature of the counter-ion X,, and also has a strong tendency to form polymeric complexes rather than dimeric or trimeric ones. [source] Improvement of crystal quality by surface mutations of ,-lactamase Toho-1ACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 4 2009Tatsuro Shimamura The ,-lactamase Toho-1 exhibits a strong tendency to form merohedrally twinned crystals. Here, the crystal quality of Toho-1 was improved by using surface modification to remove a sulfate ion involved in crystal packing. The surface-modified Toho-1 variant (R274N/R276N) was crystallized under similar conditions to those used for wild-type Toho-1. R274N/R276N did not form merohedrally twinned crystals. The crystals diffracted to a significantly higher resolution (,0.97,Å) than the wild-type crystals (1.65,Å); they belonged to the same space group and had almost identical unit-cell parameters to those of wild-type Toho-1. [source] Synthesis of peptide sequences related to thrombospondin: factors affecting aspartimide by-product formationCHEMICAL BIOLOGY & DRUG DESIGN, Issue 6 2003J. Cebrián Abstract:, Aspartimide formation is one of the most common secondary reactions on solid phase peptide synthesis. In the present work, we describe the optimization of the synthesis of two thrombospondin fragments containing an Asp-Gly sequence that show a strong tendency to form cyclic aspartimide derivatives in an unusual high percentage. Several different strategies were applied changing type of resin, Fmoc-deprotection reagents, coupling additives, resin cleavage cocktails and the use of Hmb-Gly derivative to minimize the extension of this byproduct. Best results were obtained with cross-linked ethoxylate acrylate (CLEAR® -cross-linked ethoxylate Acrylate Resin)-type resin and pip/dimethylformamide deprotection. Besides, as in biological assays the aspartimide containing sequence resulted to be more active than the linear one, the optimization of its synthesis was also carried out. [source] | |||||||||||||||||||||||||||||||||||||