Changes in a nanoparticle's spectroscopic signal mediated by the local environment

Using a first-principles theoretical model the adsorption of a methyl radical on different sized silver nanoparticles is compared to the adsorption of the same radical on model surfaces. Calculations of our structural, dynamical and electronic properties indicated that small changes in the local environment will lead to small changes in infrared (IR) wavenumbers, but in dramatic changes in the IR signal. Our calculations indicate the lower the adsorption site coordination, the higher is the signal strength, suggesting that small changes in the electronic charge distribution will result in bigger changes in the polarizability and hence in the spectroscopic signal intensity. This effect explains, among others, the signal magnification observed for nanoparticles in surface enhanced Raman spectroscopic (SERS) experiments.

Is missing maxillary lateral incisor in complete cleft lip and palate a product of genetics or local environment?

Objective: To test the null hypothesis: Subjects with isolated complete unilateral cleft lip and palate (UCLP) show no differences in overall frequency of tooth agenesis (hypodontia), comparing a subsample with cleft-side maxillary lateral incisor (MxI2) agenesis to a subsample without cleftside MxI2 agenesis. Findings could clarify the origins of cleft-side MxI2 agenesis. Materials and Methods: Tooth agenesis was identified from dental radiographs of 141 subjects with UCLP. The UCLP cohort was segregated into four categories according to the status and location of MxI2 in the region of the unilateral cleft: group M: subjects with one tooth, located on the mesial side of the alveolar cleft; group D: subjects with one tooth, located on the distal side of the alveolar cleft; group MD: subjects with two teeth present, one mesial and one distal to the cleft; and group ABS: subjects with lateral incisor absent (agenesis) in the cleft area. Results: The null hypothesis was rejected. Among UCLP subjects, there was a twofold increase (P < .0008) in overall frequency of tooth agenesis outside the cleft region in a subsample with cleftside MxI2 agenesis (ABS), compared to a subsample presenting with no agenesis of the cleft-side MxI2 (M+D+MD). Conclusions: Cleft-side MxI2 agenesis in CLP subjects appears to be largely a genetically controlled anomaly associated with cleft development, rather than a collateral environmental consequence of the adjacent cleft defect, since increased hypodontia involving multiple missing teeth observed remote from a cleft clearly has a significant genetic basis. (Angle Orthod. 2012;82:959-963.)

The local environment of Co2+ ions intercalated in vanadium oxide/hexadecylamine nanotubes

Vanadium oxide nanotubes constitute promising materials for applications in nanoelectronics as cathode materials, in sensor technology and in catalysis. In this work we present a study on hybrid vanadium oxide/hexadecylamine multiwall nanotubes doped with Co ions using state of the art x-ray diffraction and absorption techniques, to address the issue of the dopant location within the nanotubes' structure. The x-ray absorption near-edge structure analysis shows that the Co ions in the nanotubes are in the 2+ oxidation state, while extended x-ray absorption fine structure spectroscopy reveals the local environment of the Co2+ ions. Results indicate that Co atoms are exchanged at the interface between the vanadium oxide's layers and the hexadecylamines, reducing the amount of amine chains and therefore the interlayer distance, but preserving the tubular shape. The findings in this work are important for describing Co2+ interaction with vanadium oxide nanotubes at the molecular level and will help to improve the understanding of their physicochemical behavior, which is desired in view of their promising applications.

Alternaria Spores in the Air Across Europe: Abundance, Seasonality and Relationships with Climate, Meteorology and Local Environment

We explored the temporal and spatial variations in airborne Alternaria spore quantitative and phenological features in Europe using 23 sites with annual time series between 3 and 15 years. The study covers seven countries and four of the main biogeographical regions in Europe. The observations were obtained with Hirst-type spore traps providing time series with daily records. Site locations extend from Spain in the south to Denmark in the north and from England in the West to Poland in the East. The study is therefore the largest assessment ever carried out for Europe concerning Alternaria. Aerobiological data were investigated for temporal and spatial patterns in their start and peak season dates and their spore indices. Moreover, the effects of climate were checked using meteorological data for the same period, using a crop growth model. We found that local climate, vegetation patterns and management of landscape are governing parameters for the overall spore concentration, while the annual variations caused by weather are of secondary importance but should not be neglected. The start of the Alternaria spore season varies by several months in Europe, but the peak of the season is more synchronised in central northern Europe in the middle of the summer, while many southern sites have peak dates either earlier or later than northern Europe. The use of a crop growth model to explain the start and peak of season suggests that such methods could be useful to describe Alternaria seasonality in areas with no available observations.

Local Er(III) environment in luminescent titanosilicates prepared from microporous precursors

The local environment of Er3+ ions in microporous titanosilicate ETS-10 and in synthetic narsarsukite and glassy materials obtained by calcination of ETS-10 has been investigated by EXAFS, Raman and photoluminescence spectroscopies. Er L-III-edge EXAFS studies of Er3+-doped ETS-10 support the view that the exchanged Er3+ ions reside close to the (negatively charged) TiO6 octahedra. In ETS-10, Er3+ is partially bonded to framework oxygen atoms and hydration water molecules. The Er...Ti distance (3.3 Angstrom) is similar to the Na...Ti distances (3.15-3.20 Angstrom) reported previously for Na-ETS-10. Although the exact location of the ErO6 units within the host structure of Er3+-doped synthetic narsarsukite is still an open question, it is most likely that Er3+ substitutes Ti4+ rather than Na+ ions. EXAFS spectroscopy indicates that no significant clustering of erbium atoms occurs in the titanosilicate samples studied. Evidence for the insertion of Er3+ ions in the framework of narsarsukite has been obtained by Raman spectroscopy. This is indicated by the increasing full-width at half-maximum (FWHM) of the 775 cm(-1) peak and the increasing intensity of the anatase peaks as the erbium content increases. In addition, as the narsarsukite Er3+ content increases a band at ca. 515 cm(-1) firstly broadens and subsequently a new peak appears at ca. 507 cm(-1).Er3+-doped narsarsukite exhibits a characteristic local vibrational frequency, (h) over bar omega ca. 330 cm(-1), with an electron-phonon coupling, g ca. 0.2, which constitutes additional evidence for framework Er3+ insertion. The number of lines in the infrared emission spectrum of synthetic narsarsukite indicates the presence of two optically-active erbium centres with very similar local environments and an average I-4(13/2) lifetime of 7.8 +/- 0.2 ms.

Importance of the embedding environment on the strain within small rings in siliceous materials

The effect of the local environment on the energetic strain within small (SiO)N rings (with N=2,3) in silica materials is investigated via periodic model systems employing density functional calculations. Through comparison of the energies of various nonterminated systems containing small rings in strained and relatively unstrained environments, with alpha quartz, we demonstrate how small ring strain is affected by the nature of the embedding environment. We compare our findings with numerous previously reported calculations, often predicting significantly different small-ring strain energies, leading to a critical assessment of methods of calculating accurate localized ring energies. The results have relevance for estimates of the strain-induced response (e.g., chemical, photo, and radio) of small silica rings, and the propensity for them to form in bulk glasses, thin films, and nanoclusters.

Local Embeddedness and Knowledge Acquisition and How They Affect Finnish Business Operations in Russia

This pilot project aims examine the factors of the Finnish subsidiaries local embeddedness, their knowledge creation capabilities and the transfer mechanisms of new practices in the context of the Russian market. The research is designed as a multiple case study conducted with a qualitative approach. The empirical data consists of the interviews of the four Finnish case companies operating in the Kaluga region and three local partner companies. The deductive and inductive approaches were employed to conduct the analysis of the data. The propositions for the future study were developed in the conclusive chapters of the research, where we propose that the factor of the economy growth and industrialization matters in terms of subsidiaries’ role dedication, their knowledge creation capabilities, and direction of the knowledge flow within the local environment.

Environnement alimentaire local et son association avec les habitudes alimentaires de personnes âgées

Contexte : Un accès adéquat aux aliments sains dans les environnements résidentiels peut contribuer aux saines habitudes alimentaires. Un tel accès est d’autant plus important pour les personnes âgées, où les changements associés au vieillissement peuvent accentuer leur dépendance aux ressources disponibles dans le voisinage. Cependant, cette relation n’a pas encore été établie chez les aînés. Objectifs : La présente thèse vise à quantifier les associations entre l’environnement alimentaire local et les habitudes alimentaires de personnes âgées vivant à domicile en milieu urbain. La thèse s’est insérée dans un projet plus large qui a apparié les données provenant d’une cohorte d’aînés québécois vivant dans la région métropolitaine montréalaise avec des données provenant d’un système d’information géographique. Trois études répondent aux objectifs spécifiques suivants : (1) développer des indices relatifs de mixité alimentaire pour qualifier l’offre d’aliments sains dans les magasins d’alimentation et l’offre de restaurants situés dans les quartiers faisant partie du territoire à l’étude et en examiner la validité; (2) quantifier les associations entre la disponibilité relative de magasins d’alimentation et de restaurants près du domicile et les habitudes alimentaires des aînés; (3) examiner l’influence des connaissances subjectives en nutrition dans la relation entre l’environnement alimentaire près du domicile et les habitudes alimentaires chez les hommes et les femmes âgés. Méthodes : Le devis consiste en une analyse secondaire de données transversales provenant de trois sources : les données du cycle 1 pour 848 participants de l’Étude longitudinale québécoise « La nutrition comme déterminant d’un vieillissement réussi » (2003-2008), le Recensement de 2001 de Statistique Canada et un registre privé de commerces et services (2005), ces derniers regroupés dans un système d’information géographique nommé Mégaphone. Des analyses bivariées non paramétriques ont été appliquées pour répondre à l’objectif 1. Les associations entre l’exposition aux commerces alimentaires dans le voisinage et les habitudes alimentaires (objectif 2), ainsi que l’influence des connaissances subjectives en nutrition dans cette relation (objectif 3), ont été vérifiées au moyen d’analyses de régression linéaires. Résultats : Les analyses ont révélé trois résultats importants. Premièrement, l’utilisation d’indices relatifs pour caractériser l’offre alimentaire s’avère pertinente pour l’étude des habitudes alimentaires, plus particulièrement pour l’offre de restaurants-minute. Deuxièmement, l’omniprésence d’aspects défavorables dans l’environnement, caractérisé par une offre relativement plus élevée de restaurants-minute, semble nuire davantage aux saines habitudes alimentaires que la présence d’opportunités d’achats d’aliments sains dans les magasins d’alimentation. Troisièmement, un environnement alimentaire plus favorable aux saines habitudes pourrait réduire les écarts quant à la qualité de l’alimentation chez les femmes ayant de plus faibles connaissances subjectives en nutrition par rapport aux femmes mieux informées. Conclusion : Ces résultats mettent en relief la complexité des liens entre l’environnement local et l’alimentation. Dans l’éventualité où ces résultats seraient reproduits dans des recherches futures, des stratégies populationnelles visant à résoudre un déséquilibre entre l’accès aux sources d’aliments sains par rapport aux aliments peu nutritifs semblent prometteuses.

Importance of the embedding environment on the strain within small rings in siliceous materials

The effect of the local environment on the energetic strain within small (SiO)N rings (with N=2,3) in silica materials is investigated via periodic model systems employing density functional calculations. Through comparison of the energies of various nonterminated systems containing small rings in strained and relatively unstrained environments, with alpha quartz, we demonstrate how small ring strain is affected by the nature of the embedding environment. We compare our findings with numerous previously reported calculations, often predicting significantly different small-ring strain energies, leading to a critical assessment of methods of calculating accurate localized ring energies. The results have relevance for estimates of the strain-induced response (e.g., chemical, photo, and radio) of small silica rings, and the propensity for them to form in bulk glasses, thin films, and nanoclusters.

Switchable amplification of vibrational circular dichroism as a probe of local chiral structure

A new method to detect the vibrational circular dichroism (VCD) of a localized part of a chiral molecular system is reported. A local VCD amplifier was implemented, and the distance dependence of the amplification was investigated in a series of peptides. The results indicate a characteristic distance of 2.0±0.3 bonds, which suggests that the amplification is a localized phenomenon. The amplifier can be covalently coupled to a specific part of a molecule, and can be switched ON and OFF electrochemically. By subtracting the VCD spectra obtained when the amplifier is in the ON and OFF states, the VCD of the local environment of the amplifier can be separated from the total VCD spectrum. Switchable local VCD amplification thus makes it possible to “zoom in” on a specific part of a chiral molecule.

Local order around tungsten atoms in tungstate fluorophosphate glasses by X-ray absorption spectroscopy

X-ray absorption spectroscopy was used to study the local environment of tungsten atoms in NaPO3-BaF2,-WO3 glasses and the results were compared with crystalline references Na2WO4 and WO3. XANES measurements at the W-L-1 edge allowed to determine a distorted octahedral environment of tungsten atoms in these glasses similar to the local order of tungsten in monoclinic WO3. Extended X-ray absorption fine structure (EXAFS) has been used as a local probe to monitor the effect of WO3 concentration on the tungsten environment. Based on an analysis of the EXAFS data, we proposed a three-shell model of oxygen atoms around tungsten as in monoclinic WO3. With increasing WO3 concentration, it was found that R-2 decreases from 1.96 to 1.92 angstrom whereas R-3 increases from 2.07 to 2.12 angstrom. (c) 2005 Elsevier B.V. All rights reserved.

Planificación Participativa en la gestión urbana local, identificación de factores claves y nuevas formas de participación? Seguimiento a 13 Alcaldías del Área Metropolitana de Santiago, Chile

La presente tesis se presenta como un continuo de investigaciones realizadas durante el proceso de desarrollo del Doctorado en torno al tema de la Participación Ciudadana en la Gestión Urbana Local. El Objetivo general de la tesis es verificar y evaluar la existencia de una planificación participativa en la gestión urbana local en Chile. Los objetivos específicos abordan los factores clave que facilitan y restringen los procesos participativos en la gestión urbana local, la factibilidad de desarrollar nuevas formas de participación en el medio local y los avances que se han registrado o no en materia de planificación y gestión participativa en Chile. La Metodología planteada es de tipo cualitativa y se centra en el estudio del caso: la RED de Alcaldías Pro-Participación del Área Metropolitana de Santiago. Se utilizan diversos instrumentos metodológicos básicamente cualitativos donde destaca la utilización de la Transparencia Activa con 2 consultas a los 13 municipios, entrevistas a los Directores de la Secretaría de Planificación, SECPLA, a Encargados de las Unidades de Participación y con algunos Asesores Urbanos. Paralelamente en el segundo semestre del año 2013 se llevo a cabo una observación directa de los cabildos territoriales realizados en el marco del proceso de actualización del Plan de Desarrollo Comunal. Por último se realizó un Focus Group con integrantes de los Consejos de la Sociedad Civil de modo de complementar los resultados de las entrevistas y las consultas a los municipios. Todo lo anterior complementado con una revisión documental en relación a la conceptualización de la participación, los tipos de participación, los actores que intervienen en el proceso y los mecanismos o herramientas que hacen posible el desarrollo de estos procesos. Finalmente los resultados esperados, en el marco de los objetivos y las hipótesis planteadas estaban básicamente enfocados en los desafíos que impone llevar adelante una gestión más participativa y transparente. ABSTRACT This thesis is presented as a continuum of the research conducted during the development of the doctorate process on the subject of Citizen Participation in Local Urban Management. Initially referring to the more specific field of urban planning and in this case in the more general context of local planning. The overall aim of the thesis is to verify and assess the existence of participatory planning in local urban management in Chile. The specific objectives address the key factors that facilitate and constrain participatory processes in local urban management, the feasibility of developing new forms of participation in the local environment and the progress that has been registered or not in participatory planning and management in Chile. The proposed methodology is a qualitative approach and focuses on the case study: A Pro-Participation mayors of Greater Santiago. Basically using different qualitative methodological tools which highlights the use of Active Transparency with 2 consultations to the 13 municipalities, interviews with the directors of the Planning Office, SECPLAN, directors or managers of Participation Units in those municipalities that had created one and some professionals in charge of the Urban Office. Parallel to those methodological tools in the second half of 2013 was held a direct observation of the territorial councils (Caboildos Territoriales) made under the PLADECO update process. Finally, a focus group was held with members of the Civil Society Council, COSOC that will complement the results of interviews and consultations with municipalities. All this with tools in the context of a review of documents related to the conceptualization of participation, types of participation, the actors involved in the process and the mechanisms and tools that make possible these participatory processes. Finally the expected results within the framework of the objectives and hypotheses were basically focused on identifying the elements that facilitate or constrain participatory processes and identify accordingly the challenges posed pursue a more participatory and transparent management.

Climate change in mountain regions: how local communities adapt to extreme events

This paper examines how local communities adapt to climate change and how governance structures can foster or undermine adaptive capacity. Climate change policies, in general, and disaster risk management in mountain regions, in particular, are characterised by their multi-level and multi-sectoral nature during formulation and implementation. The involvement of numerous state and non-state actors at local to national levels produces a variety of networks of interaction and communication. The paper argues that the structure of these relational patterns is critical for understanding adaptive capacity. It thus proposes an expanded concept of adaptive capacity that incorporates (horizontal and vertical) actor integration and communication flow between these actors. The paper further advocates the use of formal social network analysis to assess these relational patterns. Preliminary results from research on adaptation to climate change in a Swiss mountain region vulnerable to floods and other natural hazards illustrate the conceptual and empirical significance of the main arguments.

Perceived environment attributes, residential location, and walking for particular purposes

Background: Identifying environmental factors that can influence physical activity is a public health priority. We examined associations of perceived environmental attributes with walking for four different purposes: general neighborhood walking, walking for exercise, walking for pleasure, and walking to get to and from places. Methods: Participants (n =399; 57% women) were surveyed by mail. They reported place of residence, walking behaviors, and perceptions of neighborhood environmental attributes. Results: Men with the most positive perceptions of neighborhood aesthetics were significantly more likely (odds ratio [OR] =7.4) to be in the highest category of neighborhood walking. Men who perceived the weather as not inhibiting their walking were much more likely (OR= 4.7) to be high exercise walkers. Women who perceived the weather as not inhibiting their walking were significantly more likely to be high neighborhood walkers (OR=3.8) and those with moderate perceptions of accessibility were much more likely to do more walking for pleasure (OR=3.5). Conclusions: Different environmental attributes were associated with different types of walking and these differed between men and women. Approaches to increasing physical activity might usefully focus on those attributes of the local environment that might influence particular subsets of walking behavior.