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Deeper Insight (deeper + insight)
Selected AbstractsSpeciation of Rare-Earth Metal Complexes in Ionic Liquids: A Multiple-Technique ApproachCHEMISTRY - A EUROPEAN JOURNAL, Issue 6 2009Peter Nockemann Dr. Abstract The dissolution process of metal complexes in ionic liquids was investigated by a multiple-technique approach to reveal the solvate species of the metal in solution. The task-specific ionic liquid betainium bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) is able to dissolve stoichiometric amounts of the oxides of the rare-earth elements. The crystal structures of the compounds [Eu2(bet)8(H2O)4][Tf2N]6, [Eu2(bet)8(H2O)2][Tf2N]6,2H2O, and [Y2(bet)6(H2O)4][Tf2N]6 were found to consist of dimers. These rare-earth complexes are well soluble in the ionic liquids [Hbet][Tf2N] and [C4mim][Tf2N] (C4mim=1-butyl-3-methylimidazolium). The speciation of the metal complexes after dissolution in these ionic liquids was investigated by luminescence spectroscopy, 1H, 13C, and 89Y,NMR spectroscopy, and by the synchrotron techniques EXAFS (extended X-ray absorption fine structure) and HEXS (high-energy X-ray scattering). The combination of these complementary analytical techniques reveals that the cationic dimers decompose into monomers after dissolution of the complexes in the ionic liquids. Deeper insight into the solution processes of metal compounds is desirable for applications of ionic liquids in the field of electrochemistry, catalysis, and materials chemistry. [source] Evolutionary origins of invasive populationsEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 3 2008Carol Eunmi Lee Abstract What factors shape the evolution of invasive populations? Recent theoretical and empirical studies suggest that an evolutionary history of disturbance might be an important factor. This perspective presents hypotheses regarding the impact of disturbance on the evolution of invasive populations, based on a synthesis of the existing literature. Disturbance might select for life-history traits that are favorable for colonizing novel habitats, such as rapid population growth and persistence. Theoretical results suggest that disturbance in the form of fluctuating environments might select for organismal flexibility, or alternatively, the evolution of evolvability. Rapidly fluctuating environments might favor organismal flexibility, such as broad tolerance or plasticity. Alternatively, longer fluctuations or environmental stress might lead to the evolution of evolvability by acting on features of the mutation matrix. Once genetic variance is generated via mutations, temporally fluctuating selection across generations might promote the accumulation and maintenance of genetic variation. Deeper insights into how disturbance in native habitats affects evolutionary and physiological responses of populations would give us greater capacity to predict the populations that are most likely to tolerate or adapt to novel environments during habitat invasions. Moreover, we would gain fundamental insights into the evolutionary origins of invasive populations. [source] The natural furanone (5Z)-4-bromo-5-(bromomethylene)-3-butyl-2(5H)-furanone disrupts quorum sensing-regulated gene expression in Vibrio harveyi by decreasing the DNA-binding activity of the transcriptional regulator protein luxRENVIRONMENTAL MICROBIOLOGY, Issue 10 2007Tom Defoirdt Summary This study aimed at getting a deeper insight in the molecular mechanism by which the natural furanone (5Z)-4-bromo-5-(bromomethylene)-3-butyl-2(5H)-furanone disrupts quorum sensing in Vibrio harveyi. Bioluminescence experiments with signal molecule receptor double mutants revealed that the furanone blocks all three channels of the V. harveyi quorum sensing system. In further experiments using mutants with mutations in the quorum sensing signal transduction pathway, the compound was found to block quorum sensing-regulated bioluminescence by interacting with a component located downstream of the Hfq protein. Furthermore, reverse transcriptase real-time polymerase chain reaction with specific primers showed that there was no effect of the furanone on luxRVh mRNA levels in wild-type V. harveyi cells. In contrast, mobility shift assays showed that in the presence of the furanone, significantly lower levels of the LuxRVh response regulator protein were able to bind to its target promoter sequences in wild-type V. harveyi. Finally, tests with purified LuxRVh protein also showed less shifts with furanone-treated LuxRVh, whereas the LuxRVh concentration was found not to be altered by the furanone (as determined by SDS-PAGE). Therefore, our data indicate that the furanone blocks quorum sensing in V. harveyi by rendering the quorum sensing master regulator protein LuxRVh unable to bind to the promoter sequences of quorum sensing-regulated genes. [source] Facile and Reproducible Synthesis of Nanostructured Colloidal ZnO Nanoparticles from Zinc Acetylacetonate: Effect of Experimental Parameters and Mechanistic InvestigationsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 33 2009Alessia Famengo Abstract A facile and reproducible route to nanostructured colloidal ZnO nanoparticles was developed by controlled hydrolysis and condensation of zinc acetylacetonate in alkaline conditions. By reaction of an ethanolic solution of Zn(acac)2 with NaOH in a 1:2 molar ratio, after reflux, ZnO spherical nanoparticles were obtained that displayed a homogeneous size distribution; particle diameters ranged from 6 to 10 nm, as evidenced by transmission electron microscopy (TEM) analysis. The same reaction was carried out also in water, glycerol and 1,2-propanediol, to investigate the effect of the solvent viscosity and dielectric constant on the final features of the obtained material. Irrespective of the nature of the solvent, X-ray diffraction (XRD) analysis shows the formation ofhexagonal ZnO, whereas the presence of residual unreacted Zn(acac)2 could be ruled out. Indeed, different particle sizes and very different morphologies were obtained. Also the reflux step was shown to be a key factor in avoiding the fast precipitation of a floc and achieving a pure compound, which was isolated and thoroughly characterised. The composition of the obtained ZnO was determined by elemental analysis, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA), showing the formation of pure ZnO. IR spectroscopy evidenced the presence of adsorbed organic ligands on the colloid surfaces. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) revealed the presence of medium- to high-strength acidic sites on the ZnO surface. To gain a deeper insight into the formation mechanisms of these nanostructures, time-resolved UV/Vis and XAS studies were performed on the ethanol solution used for the synthesis of the oxide and also on the solid specimen, obtained after the refluxing step. No remarkable changes could be evidenced in the solution after the addition of an understoichiometric amount of NaOH, but the growth of the ZnO nanoparticles could be followed by UV/Vis spectra. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] sgk1, a member of an RNA cluster associated with cell death in a model of Parkinson's diseaseEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2005Christine C. Stichel Abstract In an effort to gain deeper insight into the molecular processes underlying neurodegeneration in Parkinson's disease, we performed gene expression profiling at several early time points after MPTP-injection into old (1-year) mice. We used a PCR-based gene expression profiling method, digital expression pattern display (DEPD), a method of very high sensitivity and reproducibility, which displays almost all transcripts of a tissue. To identify cell death-associated genes, we defined clusters of differentially expressed transcripts with expression behaviour that correlated with the temporal profile of cell death progression and characterized one of these cell death clusters further. We selected one of the strongest regulated genes, the serum and glucocorticoid-regulated kinase 1 (sgk1), and validated its differential expression by Northern blot analysis, semiquantitative PCR and in situ hybridization. Up-regulation of sgk1 (i) coincides with the onset of dopaminergic cell death in both the 8-week acute and 1-year subacute MPTP models, (ii) spans the entire brain, (iii) is attenuated by the l -deprenyl-mediated inhibition of the MPTP conversion to its active metabolite MPP+ and (iv) is not induced by dehydration. This study demonstrated that the combination of the DEPD technology, clustering analysis and a detailed histopathology is a useful tool for elucidating molecular pathways in neurodegenerative diseases. [source] Image-processing chain for a three-dimensional reconstruction of basal cell carcinomas,EXPERIMENTAL DERMATOLOGY, Issue 7 2010Patrick Scheibe Please cite this paper as: Image-processing chain for a three-dimensional reconstruction of basal cell carcinomas. Experimental Dermatology 2010; 19: 689,691. Abstract:, Basal cell carcinoma (BCC) is the most common malignant skin cancer. For a deeper insight into the specific growth patterns of the tumorous tissue in BCC, we have focused on the development of a novel automated image-processing chain for 3D reconstruction of BCC using histopathological serial sections. For fully automatic delineation of the tumor within the tissue, we apply a fuzzy c-means segmentation method. We used a novel multi-grid form of the non-linear registration introduced by Braumann and Kuska in 2005 effectively suppressing registration runs into local minima (possibly caused by diffuse nature of the tumor). Our method was successfully applied in a proof-of-principle study for automated reconstruction. [source] White Electroluminescence by Supramolecular Control of Energy Transfer in Blends of Organic-Soluble Encapsulated PolyfluorenesADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Sergio Brovelli Abstract Here, it is demonstrated that energy transfer in a blend of semiconducting polymers can be strongly reduced by non-covalent encapsulation of one constituent, ensured by threading of the conjugated strands into functionalized cyclodextrins. Such macrocycles control the minimum intermolecular distance of chromophores with similar alignment, at the nanoscale, and therefore the relevant energy transfer rates, thus enabling fabrication of white-light-emitting diodes (CIE coordinates: x,=,0.282, y,=,0.336). In particular, white electroluminescence in a binary blend of a blue-emitting, organic-soluble rotaxane based on a polyfluorene derivative and the green-emitting poly(9,9-dioctylfluorene-alt-benzothiadiazole (F8BT) is achieved. Morphological and structural analyses by atomic force microscopy, fluorescence mapping, µ-Raman, and fluorescence lifetime microscopy are used to complement optical and electroluminescence characterization, and to enable a deeper insight into the properties of the novel blend. [source] Analytical and 3-D numerical modelling of Mt. Etna (Italy) volcano inflationGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2005A. Bonaccorso SUMMARY Since 1993, geodetic data obtained by different techniques (GPS, EDM, SAR, levelling) have detected a consistent inflation of the Mt. Etna volcano. The inflation, culminating with the 1998,2001 strong explosive activity from summit craters and recent 2001 and 2002 flank eruptions, is interpreted in terms of magma ascent and refilling of the volcanic plumbing system and reservoirs. We have modelled the 1993,1997 EDM and GPS data by 3-D pressurized sources to infer the position and dimension of the magma reservoir. We have performed analytical inversions of the observed deformation using both spheroidal and ellipsoidal sources embedded in a homogeneous elastic half-space and by applying different inversion methods. Solutions for these types of sources show evidence of a vertically elongated magma reservoir located 6 km beneath the summit craters. The maximum elevation of topography is comparable to such depth and strong heterogeneities are inferred from seismic tomography; in order to assess their importance, further 3-D numerical models, employing source parameters extracted from analytical models, have been developed using the finite-element technique. The deformation predicted by all the models considered shows a general agreement with the 1993,1997 data, suggesting the primary role of a pressure source, while the complexities of the medium play a minor role under elastic conditions. However, major discrepancies between data and models are located in the SE sector, suggesting that sliding along potential detachment surfaces may contribute to amplify deformation during the inflation. For the first time realistic features of Mt. Etna are studied by a 3-D numerical model characterized by the topography and lateral variations of elastic structure, providing a framework for a deeper insight into the relationships between internal sources and tectonic structures. [source] Charge Transport Physics of Conjugated Polymer Field-Effect TransistorsADVANCED MATERIALS, Issue 34 2010Henning Sirringhaus Abstract Field-effect transistors based on conjugated polymers are being developed for large-area electronic applications on flexible substrates, but they also provide a very useful tool to probe the charge transport physics of these complex materials. In this review we discuss recent progress in polymer semiconductor materials, which have brought the performance and mobility of polymer devices to levels comparable to that of small-molecule organic semiconductors. These new materials have also enabled deeper insight into the charge transport physics of high-mobility polymer semiconductors gained from experiments with high charge carrier concentration and better molecular-scale understanding of the electronic structure at the semiconductor/dielectric interface. [source] Investigation of Charge-Carrier Injection in Ambipolar Organic Light-Emitting Field-Effect TransistorsADVANCED MATERIALS, Issue 10-11 2009Martin Schidleja Organic light-emitting field-effect transistors provide a deeper insight into the physics of ambipolar devices. Here, the source and drain contacts are altered to investigate the influence of injection barriers on the performance of ambipolar field-effect transistors. The experimental results are compared to a straightforward numerical model. [source] Capturing the voice of older consumers in relation to financial products and servicesINTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 2 2010Carol Brennan Abstract The purpose of this pilot study was to focus on the suitability of selected financial products for older people. Bank accounts and equity release products were selected for this study by an expert advisory panel. New marketing initiatives are being used to promote bank accounts, including forms of insurance, for the ,50+' market. Also, older people are now expected to provide for their retirement and it is anticipated that equity release will be one product which may be used to fund and maintain consumer lifestyles. In the first phase of the study, a questionnaire was distributed to 152 people aged over 50 years in Scotland. Eighty-three were completed, a response rate of 55%. The results informed the development of questions for the second phase which were discussed with 46 participants via the World Café in June 2008, enabling a deeper insight into their opinions. The research found that consumers had lost trust in financial product and service providers because of the perceived excessive profits of banks and lack of customer service. Further, many products and services were prohibited for or incurred extra costs to those aged over 60 or 65 years, leaving limited choices, and equity release products were seen as a last resort for those in financial difficulty. Although the profitability of banks has changed dramatically since the completion of data collection, the issues identified by older consumers in Scotland will be of international interest. The demographic changes resulting in an increasing proportion of elderly people in the population are reflected throughout the UK and many Organisation for Economic Co-operation and Development countries. Similar financial products and services, which were the focus of this study, are promoted internationally, offering opportunities to replicate the research methods. [source] Accident and emergency staff opinion on the effects of family presence during adult resuscitation: critical literature reviewJOURNAL OF ADVANCED NURSING, Issue 4 2008Wendy Walker Abstract Title.,Accident and emergency staff opinion on the effects of family presence during adult resuscitation: critical literature review. Aim., This paper is a report of a critical literature review to identify the positive and negative effects of family presence during adult resuscitation, as perceived by accident and emergency healthcare staff based in primary (out-of-hospital) and secondary (in-hospital) environments of care. Background., The controversial practice of family presence during resuscitation of adults has stimulated debate over the past two decades, giving rise to a growing body of literature and the development of clinical guidelines for practice. Methods., A search was carried out for the period 1987,2007 using the Science Direct, CINAHL, Medline, EMBASE, psychINFO and BNI databases and the search terms resuscitation, witnessed resuscitation, family presence, relatives' presence, attitudes and opinions and accident and emergency. Results., Eighteen studies were included in the critical review, primarily comprising retrospective survey research. The majority of studies were descriptive in design. A standardized approach to the appraisal process was achieved through the utilization of guidelines for critiquing self-reports. The findings revealed that accident and emergency healthcare staff perceive both positive and negative effects as a consequence of family presence during adult resuscitation and their opinions suggest that there are more risks than benefit. Conclusion., Further research is essential if family presence during resuscitation of adults is to be better defined and understood. Qualitative methods of enquiry are recommended as a way of gaining a deeper insight into and understanding of this practice. [source] Reconstructing impairment of secretory ameloblast function in porcine teeth by analysis of morphological alterations in dental enamelJOURNAL OF ANATOMY, Issue 1 2006Carsten Witzel Abstract We studied the relationship between the macroscopic appearance of hypoplastic defects in the dental enamel of wild boar and domestic pigs, and microstructural enamel changes, at both the light and the scanning electron microscopic levels. Deviations from normal enamel microstructure were used to reconstruct the functional and related morphological changes of the secretory ameloblasts caused by the action of stress factors during amelogenesis. The deduced reaction pattern of the secretory ameloblasts can be grouped in a sequence of increasingly severe impairments of cell function. The reactions ranged from a slight enhancement of the periodicity of enamel matrix secretion, over a temporary reduction in the amount of secreted enamel matrix, with reduction of the distal portion of the Tomes' process, to either a temporary or a definite cessation of matrix formation. The results demonstrate that analysis of structural changes in dental enamel allows a detailed reconstruction of the reaction of secretory ameloblasts to stress events, enabling an assessment of duration and intensity of these events. Analysing the deviations from normal enamel microstructure provides a deeper insight into the cellular changes underlying the formation of hypoplastic enamel defects than can be achieved by mere inspection of tooth surface characteristics alone. [source] Genetic aspects concerning drip loss and water-holding capacity of porcine meatJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 2007D. G. J. Jennen Summary The amount and distribution of water inside the meat has a considerable influence on its properties. High losses of fluid in the form of drip may affect financial output, nutritional value, consumer appeal and/or technological properties of porcine meat. Therefore, a deeper insight into the traits water-holding capacity (WHC) and drip is favourable on behalf of producers, industry and consumers. Similar to most meat quality traits, WHC and drip loss (DRIP) are moderately heritable. The genetic correlation between these two traits is high. Correlation to other meat quality traits, such as pH value, cooking loss, reflectance, etc. is existent as predictable. Two major genes are known, RYR1 on chromosome 6 and RN on chromosome 15, to influence meat quality in general and WHC in particular. Furthermore, a number of candidate genes exist, e.g. phosphoglycerate mutase 2. Within the variety of quantitative trait loci (QTL) experiments, a number of QTL have been identified. QTL for DRIP and/or WHC have been found on chromosome 1, 2, 4, 5, 6, 11, 13, 14, 15, 18; for cooking loss on 7, 14 and18, and for pH value on nearly all chromosomes. Recently, a QTL study for meat quality and body composition traits in a Duroc,Pietrain (DUPI) resource population has been conducted at the University of Bonn, Germany. Four QTL for DRIP were identified on chromosomes 2, 3, 5 and 18. The QTL regions are in agreement with previously published QTL for this and other related traits. Further research and finemapping has begun and candidate genes located within the QTL regions are currently under investigation. Combination and comparison of results should lead to deeper insights in the genetic background of meat quality and DRIP. [source] Influence of Grafting on the Solution Properties and the Dissociation Behavior of Ionic/Nonionic Grafted CopolymersMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 6 2007Jens Weber Abstract A new synthetic approach towards grafted terpolymers based on a poly[(methyl vinyl ether)- alt -(maleic anhydride)] backbone and poly(ethylene glycol) monomethyl ether (MPEG) side chains is presented. Resulting comb polymers with controllable grafting degree still have highly reactive anhydride moieties along the polymer backbone, as proved by IR spectroscopy. Grafting degree depends on the anhydride hydroxide stoichiometric ratio. It is not influenced by the molecular weight of MPEG. An increase in the grafting degree leads to a contraction of the polymer in the solution. Evaluation of potentiometric titration data gave a deeper insight into the dissociation process. The copolymers showed a two-step dissociation behavior. No significant influence of the grafting degree on the acidic strength was observed, whilst there is a strong effect of the grafting degree on the free energy change upon neutralization ,Gel. Grafting leads to a higher change in free energy ,Gel,1 for the first step but to lower ,Gel,2 required for the second step. [source] Shielding Effects in Polymer-Polymer Reactions, 1MACROMOLECULAR THEORY AND SIMULATIONS, Issue 6 2007Z-RAFT Star Polymerization of Four-Arm Stars Abstract Shielding effects of the surrounding arms and chains on the reactive centers taking part in RAFT four-arm star polymerization following the Z-group approach are calculated by means of exact enumeration of star/chain samples prepared by Monte Carlo techniques. The shielding effect, which can be relieved when using expanded core moieties, increases with increasing chain (arm) lengths. This leads to a reduction of the contact probability according to a power law with an exponent of ,0.4 to ,0.45. Additionally, characteristic chain properties and shape parameters are calculated as a function of the distance between the center of the star and the end of the linear chain in order to gain deeper insight into the mechanism of contact formation preceding the actual reaction. [source] Frequency domain lifetime and spectral imaging microscopyMICROSCOPY RESEARCH AND TECHNIQUE, Issue 11 2006Serge Pelet Abstract In the femtoliter observation volume of a two-photon microscope, multiple fluorophores can be present and complex photophysics can take place. Combined detection of the fluorescence emission spectra and lifetimes can provide deeper insight into specimen properties than these two imaging modalities taken separately. Therefore, we have developed a detection scheme based on a frequency-modulated multichannel photomultiplier, which measures simultaneously the spectrum and the lifetime of the emitted fluorescence. Experimentally, the efficiency of the frequency domain lifetime measurement was compared to a time domain set-up. The performance of this spectrally and lifetime-resolved microscope was evaluated on reference specimens and living cells labeled with three different stains targeting the membrane, the mitochondria, and the nucleus. Microsc. Res. Tech., 2006. © 2006 Wiley-Liss, Inc. [source] DIGE compatible labelling of surface proteins on vital cells in vitro and in vivoPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 2 2006Corina Mayrhofer Abstract Efficient methods for profiling of the cell surface proteome are desirable to get a deeper insight in basic biological processes, to localise proteins and to uncover proteins differentially expressed in diseases. Here we present a strategy to target cell surface exposed proteins via fluorescence labelling using CyDye DIGE fluors. This method has been applied to human cell lines in vitro as well as to a complex biological system in vivo. It allows detection of fluorophore-tagged cell surface proteins and visualisation of the accessible proteome within a single 2-D gel, simplifying subsequent UV MALDI-MS analysis. [source] Modulation of gene expression by extracellular pH variations in human fibroblasts: A transcriptomic and proteomic studyPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 5 2003Maja A. Bumke Abstract Homeostasis of the intracellular ionic concentration, in particular that of hydrogen ions, is pivotal to the maintenance of cell function and viability. Nonetheless, pH fluctuations in both the intracellular and the extracellular compartments can occurr during development, in physiological processes and in disease. The influence of pH variations on gene expression has been studied in different model systems, but only for a limited number of genes. We have performed a broad range analysis of the patterns of gene expression in normal human dermal fibroblasts at two different pH values (in the presence and in the absence of serum), with the aim of getting a deeper insight into the regulation of the transcriptional program as a response to a pH change. Using the Affymetrix gene chip system, we found that the expression of 2068 genes (out of 12,565) was modulated by more than two-fold at 24, 48 or 72 h after the shift of the culture medium pH to a more acidic value, stanniocalcin 1 being a remarkable example of a strongly up-regulated gene. Genes displaying a modulated pattern of expression included, among others, cell cycle regulators (consistent with the observation that acidic pH abolishes the growth of fibroblasts in culture) and relevant extracellular matrix (ECM) components. Extracellular matrix protein 2, a protein with a restricted pattern of expression in adult human tissues, was found to be remarkably overexpressed as a consequence of serum starvation. Since ECM components, whose expression is controlled by pH, have been used as targets for biomolecular intervention, we have complemented the Affymetrix analysis with a two-dimensional polyacrylamide gel electrophoresis analysis of proteins which are differentially secreted by fibroblasts at acidic or basic pH. Mass spectrometric analysis of more than 650 protein spots allowed the identification of 170 protein isoforms or fragments, belonging to 40 different proteins. Some proteins were only expressed at basic pH (including, for instance, tetranectin), while others (e.g., agrin) were only detectable at acidic pH. Some of the identified proteins may represent promising candidate targets for biomedical applications, e.g., for antibody-mediated vascular targeting strategies. [source] Heparan Sulfate Accumulation with A, Deposits in Alzheimer's Disease and Tg2576 Mice is Contributed by Glial CellsBRAIN PATHOLOGY, Issue 4 2008Paul O'Callaghan Abstract Amyloid ,-peptide (A,) plaques, one of the major neuropathological lesions in Alzheimer's disease (AD), can be broadly subdivided into two morphological categories: neuritic and diffuse. Heparan sulfate (HS) and HS proteoglycans (HSPGs) are codeposits of multiple amyloidoses, including AD. Although HS has been considered a limiting factor in the initiation of amyloid deposition, the pathological implications of HS in A, deposits of AD remain unclear. In this study, immunohistochemistry combined with fluorescence and confocal microscopy was employed to gain deeper insight into the accumulation of HS with A, plaques in sporadic and familial AD. Here we demonstrate that HS preferentially accumulated around the A,40 dense cores of neuritic plaques, but was largely absent from diffuse A,42 plaques, suggesting that A,42 deposition may occur independently of HS. A codeposition pattern of HS with A, deposits in Tg2576 mice was also examined. We identified the membrane-bound HSPGs, glypican-1 (GPC1) and syndecan-3 (SDC3), in glial cells associated with A, deposits, proximal to sites of HS accumulation. In mouse primary glial cultures, we observed increased levels of GPC1 and SDC3 following A, stimulation. These results suggest that HS codeposits with A,40 in neuritic plaques and is mainly derived from glial cells. [source] Age-related changes in skin wrinkles assessed by a novel three-dimensional morphometric analysisBRITISH JOURNAL OF DERMATOLOGY, Issue 4 2002S. Akazaki SummaryBackground,A system has been developed whereby the morphology of the skin surface can be evaluated directly in three dimensions. This system employs a non-invasive device that utilizes white light of halogen origin, and which allows the computation of wrinkle depth and width, and other parameters of skin surface morphology. Using innovative engineering, an optical system has been devised so that light is transmitted via a slit and can be used to measure not only replicas of the skin but also the skin surface directly. The measurement area is 6·4 × 6·4 mm, and the theoretical resolution with a × 50 magnification lens is within 12·5 µm. Objectives,To use this system to study age-related changes in the morphology of wrinkles at the eye corner areas of women of varying ages. Methods,One hundred and one healthy women (age range 20,80 years) residing in the Tokyo area were the subjects used in this study. Results,Wrinkles demonstrated a rapid increase in depth in women aged 40 years or older, and plateaued at the age of 60 years. Surface morphology parameters yielded results similar to those of age-related changes in wrinkles. Conclusions,This new analytical system provides a rapid and convenient non-invasive method to evaluate skin surface morphology in three dimensions, especially with respect to wrinkle formation. The results obtained using this system provide a deeper insight into the mechanistic relationship between wrinkles and skin elasticity. [source] Drusen in adaptive optics and SD-OCTACTA OPHTHALMOLOGICA, Issue 2009N MASSAMBA Purpose The study objective was to explore the microscopic structure of soft macular drusen and surrounding retinal areas using an adaptive optics (AO) camera and to compare the findings to those from standard clinical examinations. Methods 18 patients of age between 65 and 85 and presenting soft macular drusen were recruited after aninitial scanning laser ophthalmoscope (SLO) examination. We used an AO flood-illumination system to acquire high-resolution images of selected drusen areas. Every acquisition provided a series of 20 consecutive reflectance images, out of which 10 were numerically averaged to produce an enhanced final image. The resulting AO images were analyzed in comparison with conventional infrared and autofluorescence fundus images and spectral optical coherence tomography scans. Results The soft drusen were visible in AO images as generally round areas delimited by a peripheral low-reflectance line. Hyper reflective spots of size comprised between 2 and 15 ,m were observed in many drusen inner areas. These bright spots were sometimes isolated, sometimes grouped into tight aggregates of 2 to 40 components. Cone photoreceptors were visible in areas between drusen in most AO images. Conclusion The microscopic structures observed in the AO images of soft drusen presents analogies with their described anatomopathologic characteristics, which could not be identified using other in vivo imaging techniques. AO technology could help to refine the clinical classification of macular drusen and obtain deeper insight in their link with the development of different types of advanced AMD. Author Disclosure Information: N. Massamba, None; B. Lamory, Imagine Eyes, G. Soubrane, None. [source] Mechanism and exo -Regioselectivity of Organolanthanide-Mediated Intramolecular Hydroamination/Cyclization of 1,3-Disubstituted Aminoallenes: A Computational StudyCHEMISTRY - A EUROPEAN JOURNAL, Issue 9 2006Sven Tobisch Priv.-Doz. Abstract The complete catalytic reaction course for the organolanthanide-assisted intramolecular hydroamination/cyclization (IHC) of 4,5-heptadien-1-ylamine by a prototypical [(,5 -Me5C5)2LuCH(SiMe3)2] precatalyst has been critically scrutinized by employing a reliable DFT method. A computationally verified mechanistic scenario for the IHC of 1,3-disubstituted aminoallene substrates has been proposed that is consistent with the empirical rate law determined by experiment and accounts for crucial experimental observations. It involves kinetically rapid substrate association and dissociation equilibria, facile and reversible intramolecular allenic CC insertion into the LnN bond, and turnover-limiting protonation of the azacycle's tether functionality, with the amine-amidoalleneLn adduct complex representing the catalyst's resting state. This mechanistic scenario bears resemblance to the mechanism that has been recently proposed in a computational exploration of aminodiene IHC. The unique features of the IHC of the two substrate classes are discussed. Furthermore, the thermodynamic and kinetic factors that control the regio- and stereoselectivity of aminoallene IHC have been elucidated. These achievements have provided a deeper insight into the catalytic structure,reactivity relationships in organolanthanide-assisted cyclohydroamination of unsaturated CC functionalities. [source] Scanning Force Microscopy Based Rapid Force Curve Acquisition on Supported Lipid Bilayers: Experiments and Simulations Using Pulsed Force ModeCHEMPHYSCHEM, Issue 7 2004Stephanie Krüger Dr. Abstract In situ pulsed force mode scanning force microscopy (PFM,SFM) images of phase separated solid-supported lipid bilayers are discussed with the help of computer simulations. Simultaneous imaging of material properties and topography in a liquid environment by means of PFM,SFM is severely hampered by hydrodynamic damping of the cantilever. Stiffness and adhesion images of solid-supported membranes consisting of cholesterol, sphingomyelin, and 1,2-dioleyl-phosphatidylcholine obtained in aqueous solution exhibit contrast inversion of adhesion and stiffness images depending on parameters such as driving frequency, amplitude, and trigger setting. Simulations using a simple harmonic oscillator model explain experimental findings and give a deeper insight into the way PFM,SFM experiments have to be performed in order to obtain interpretable results and hence pave the way for reliable material contrast imaging at high speed. [source] The experiences of children living with and caring for parents with mental illnessCHILD ABUSE REVIEW, Issue 2 2006Jo Aldridge Abstract This research provides a three-way perspective on the experiences and needs of children who are living with and caring for parents with severe and enduring mental illness. The views of children, parents and key workers were sought in order to provide deeper insight into the needs of families and the nature of interfamilial relationships, as well as the relationships between service users and providers. Child protection and medical research has long proposed a link between parental mental illness and the risk to children of abuse, neglect and developmental delay. The inevitability of risk associations is challenged by the research described here and outcomes for children of caring for parents with mental illness are discussed not simply in terms of risk to children but more broadly in respect of, for example, positive parent,child relationships. Copyright © 2006 John Wiley & Sons, Ltd. [source] Biogeography of wetland rice methanotrophsENVIRONMENTAL MICROBIOLOGY, Issue 4 2010Claudia Lüke Summary We focused on the functional guild of methane oxidizing bacteria (MOB) as model organisms to get deeper insights into microbial biogeography. The pmoA gene was used as a functional and phylogenetic marker for MOB in two approaches: (i) a pmoA database (> 4000 sequences) was evaluated to obtain insights into MOB diversity in Italian rice paddies, and paddy fields worldwide. The results show a wide geographical distribution of pmoA genotypes that seem to be specifically adapted to paddy fields (e.g. Rice Paddy Cluster 1 and Rice Paddy Cluster 2). (ii) On the smaller geographical scale, we designed a factorial experiment including three different locations, two rice varieties and two habitats (soil and roots) within each of three rice fields. Multivariate analysis of terminal restriction fragment analysis profiles revealed different community patterns at the three field sites, located 10,20 km apart. Root samples were characterized by high abundance of type I MOB whereas the rice variety had no effect. With the agronomical practice being nearly identical, historical contingencies might be responsible for the field site differences. Considering a large reservoir of viable yet inactive MOB cells acting as a microbial seed bank, environmental conditions might have selected and activated a different subset at a time thereby shaping the community. [source] METAMODELS AND PHYLOGENETIC REPLICATION: A SYSTEMATIC APPROACH TO THE EVOLUTION OF DEVELOPMENTAL PATHWAYSEVOLUTION, Issue 11 2009Artyom Kopp Molecular genetic analysis of phenotypic variation has revealed many examples of evolutionary change in the developmental pathways that control plant and animal morphology. A major challenge is to integrate the information from diverse organisms and traits to understand the general patterns of developmental evolution. This integration can be facilitated by evolutionary metamodels,traits that have undergone multiple independent changes in different species and whose development is controlled by well-studied regulatory pathways. The metamodel approach provides the comparative equivalent of experimental replication, allowing us to test whether the evolution of each developmental pathway follows a consistent pattern, and whether different pathways are predisposed to different modes of evolution by their intrinsic organization. A review of several metamodels suggests that the structure of developmental pathways may bias the genetic basis of phenotypic evolution, and highlights phylogenetic replication as a value-added approach that produces deeper insights into the mechanisms of evolution than single-species analyses. [source] The Impact of Occupational Sex Segregation on Family Businesses: The Case of American Harness RacingGENDER, WORK & ORGANISATION, Issue 4 2006Elizabeth A. Larsen Previous research on occupational sex segregation agrees that the workplace is not an isolated world but instead influences, and is influenced by, other spheres of social life. Identifying specific social factors both internal and external to the workplace, and how these may interact, can provide deeper insights into how occupational sex segregation is created and maintained. This study focuses on individual family businesses in American harness horse racing, a previously unexamined and highly sex-segregated industry, and provides insights in how vertical and horizontal sex segregation may develop in family businesses. The findings show how the belief that married couples cannot debate and resolve work-related conflicts without undue strain on their personal relationship leads some of these couples to organize their work into gendered tasks and workspaces, contributing to the maintenance of vertical segregation in the trainer position. The implications for segregation of other solutions, such as operating separate businesses, or working for another business, are less clear. [source] Team coaching helps a leadership team drive cultural change at CaterpillarGLOBAL BUSINESS AND ORGANIZATIONAL EXCELLENCE, Issue 4 2008Merrill C. Anderson Team coaching readied NACD's top leaders for a broad cultural initiative, showing them how to be more effective with each other, and then how to drive behavioral change across the business by embodying the principles of service. The three-phase initiative included coaching activities such as peer feedback, individual coaching engagements, in-the-moment group coaching, and coaching skills training. The leadership team dealt with its nonproductive habits of interaction; gained deeper insights about the individual and organizational behavior changes needed to implement a customer-centric culture of service; defined and held each other accountable for new behavioral norms; and instituted processes to make its discussions and decision making more effective. © 2008 Wiley Periodicals, Inc. [source] Crossed-Beam and Quantum Dynamics Studies of the Reaction Cl + CHD3ISRAEL JOURNAL OF CHEMISTRY, Issue 1 2007Gunnar Nyman The ground-state reaction of Cl + CHD3 was studied with joint experimental and theoretical efforts. Experiments were performed under crossed-beam conditions using a time-sliced velocity imaging detection method. By taking the images over the energy range of chemical significance,from threshold to about 9 kcal/mol,the reactive excitation functions as well as the dependence of product angular distributions and of the energy disposal on initial collision energies were obtained for both isotopic product channels. Theoretically, reduced dimensionality quantum dynamics calculations were performed for the HCl + CD3 channel, and the results are in excellent agreement with experimental findings. Comparisons with previously reported results on Cl + CH4/CD4, both experimental and theoretical, were also made to gain deeper insights into the dynamics of this benchmark atom + polyatomic reaction. [source] | ||||||||||||||||||||||||||||