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N-Arylation reaction is obtained when 2′-halo-[1,1′-biphenyl]-2-amines are irradiated in basic medium. On the basis of photochemical, photophysical experiments and computational studies we propose that carbazoles are formed by intermolecular electron transfer via SRN1 mechanism. In general, biphenylamines with an EDG like Me or OMe behave in the same way as H giving both, cyclized and reduced products. On the other hand, biphenylamines containing EWG like CN, COOEt or CF3gave only the corresponding carbazole. Herein, we report for the first time the chain length for the propagation cycle of intramolecular SRN1 reactions and explain that differences in the distribution of products suggest differences regarding the overall mechanism involved. Fil: Guerra, Walter Damián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Buden, Maria Eugenia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Barolo, Silvia Maricel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Rossi, Roberto Arturo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina Fil: Pierini, Adriana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; Argentina

Accurately assessing terrestrial gross primary productivity (GPP) is crucial for characterizing the climate-carbon cycle. Remotely sensing the photochemical reflectance index (PRI) across vegetation functional types and spatiotemporal scales has received increasing attention for monitoring photosynthetic performance and simulating GPP over the last two decades. The factors confounding PRI variation, especially on long timescales, however, require the improvement of PRI understanding to generalize its use for estimating carbon uptake. In this review, we summarize the most recent publications that have reported the factors affecting PRI variation across diurnal and seasonal scales at foliar, canopy and ecosystemic levels; synthesize the reported correlations between PRI and ecophysiological variables, particularly with radiation-use efficiency (RUE) and net carbon uptake; and analyze the improvements in PRI implementation. Long-term variation of PRI could be attributed to changes in the size of constitutive pigment pools instead of xanthophyll de-epoxidation, which controls the facultative short-term changes in PRI. Structural changes at canopy and ecosystemic levels can also affect PRI variation. Our review of the scientific literature on PRI suggests that PRI is a good proxy of photosynthetic efficiency at different spatial and temporal scales. Correcting PRI by decreasing the influence of physical or physiological factors on PRI greatly strengthens the relationships between PRI and RUE and GPP. Combining PRI with solar-induced fluorescence (SIF) and optical indices for green biomass offers additional prospects. Fil: Zhang, Chao. Consejo Superior de Investigaciones Científicas; España. Universitat Autònoma de Barcelona; España. Centro de Investigación Ecológica y Aplicaciones Forestales; España Fil: Filella, Iolanda. Consejo Superior de Investigaciones Científicas; España. Universitat Autònoma de Barcelona; España. Centro de Investigación Ecológica y Aplicaciones Forestales; España Fil: Garbulsky, Martín Fabio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura. Universidad de Buenos Aires. Facultad de Agronomía. ; Argentina. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Animal. Cátedra de Forrajicultura; Argentina Fil: Peñuelas, Josep. Consejo Superior de Investigaciones Científicas; España. Universitat Autònoma de Barcelona; España. Centro de Investigación Ecológica y Aplicaciones Forestales; España

Submitted by Gabriela Lopes (gmachadolopesufpel@gmail.com) on 2016-09-26T14:38:00Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Lisiane - Final 1.3.pdf: 2575911 bytes, checksum: e1b3f8411383f73d3a79b306974f2334 (MD5) Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2016-09-26T18:40:01Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Lisiane - Final 1.3.pdf: 2575911 bytes, checksum: e1b3f8411383f73d3a79b306974f2334 (MD5) Made available in DSpace on 2016-09-26T18:40:01Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertação - Lisiane - Final 1.3.pdf: 2575911 bytes, checksum: e1b3f8411383f73d3a79b306974f2334 (MD5) Previous issue date: 2016-05-12 Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul - FAPERGS Bala mastigável é um produto obtido da cocção de açúcares que se caracteriza por ser mastigável (gomoso) e de dissolução relativamente lenta na boca e cuja cor, sabor, aroma e/ou textura devem-se aos aditivos químicos. A inserção de frutas na formulação de balas mastigáveis pode eliminar ou reduzir o uso destes aditivos, além de incorporar compostos da fruta associados a benefícios à saúde. Neste trabalho, objetivou-se desenvolver balas mastigáveis convencionais e de reduzido valor calórico utilizando polpas de araçás e de pitanga, avaliando suas características físico-químicas, fitoquímicas, microbiológicas e apresentando características sensoriais agradáveis, além da estabilidade no armazenamento. Com relação à composição centesimal este estudo mostrou que as balas sofreram modificações ao longo do armazenamento ocorrendo o fenômeno da “mela”. Os parâmetros físico-químicos avaliados demonstraram estar adequados para este tipo de produto. O processamento e armazenamento por 180 dias influenciaram na composição fitoquímica e antioxidante das balas, onde se observou maior conteúdo nas formulações convencionais devido ao maior percentual de polpa (7,2 %) nesta bala. As balas de reduzido valor calórico apresentaram menor teor de lipídios que as balas convencionais e podem ser categorizadas como bala light em lipídios. As balas elaboradas neste estudo não apresentaram contaminação por coliformes termotolerantes e Salmonella sp. Na avaliação sensorial com crianças (consumidores usuais deste tipo de produto) entre 5 a 10 anos, obteve-se índice de aceitabilidade superior a 70 % indicando que os produtos balas têm um bom potencial para consumo. Chewable candy is a product obtained from the cooking sugar which is characterized by being chewy (gummy) and relatively slow dissolution in the mouth and whose color, taste, flavor or texture and are due to the chemical additives. The inclusion of fruits in formulating chewable candy can eliminate or reduce the use of these additives, as well as incorporating fruit compounds associated with health benefits. This study aimed to develop conventional chewable candies and reduced calorie using pulps araçás and cherry, assessing their physicochemical properties, phytochemical, microbiological and featuring pleasant sensory characteristics, as well as storage stability. With respect to composition proximate this study showed that candies were modified during the storage occurring the phenomenon of "mela". The physicochemical parameters evaluated demonstrated to be suitable for this type of product. The processing and storage for 180 days influenced the phytochemical composition and antioxidant candies where there was a greater content in conventional formulations due to the higher percentage of pulp (7.2 %) in this candy. The reduced caloric value candies had a lower lipid content than the conventional ones and they can be categorized as light candies in lipids. The candies developed in this study showed no contamination by fecal coliforms and Salmonella sp. The sensory evaluation with children (usual consumers of this type of product) from 5 to 10 years, we obtained higher acceptance rate to 70 % indicating that candies products have good potential for consumption.

The paper discusses the utilization budgets of the excitation energy ofphytoplankton pigment molecules activated on absorbing solar radiation undervarious typical conditions obtaining in the World Ocean. The deactivation of these molecules following the conversion ofthe excitation energy to the fluorescence of chlorophyll a, the photosynthesis of organic matter and heat is takeninto account. To this end, a great many model computations were performed;these made use of the authors' earlier models of the dependence of the quantumyields and energy efficiencies of the above processes on the threeprincipal environmental factors governing the functioning of marine plantcommunities: the chlorophyll a concentration in the surface water layer(the trophic index of waters), temperature and the underwater irradiance atdifferent depths in the sea. These model relationships were used to determinevertical profiles of the quantum yields and energy efficiencies of thechlorophyll a fluorescence, photosynthesis and heat production byphytoplankton in different trophic types of sea in three different climaticzones (tropical, temperate and polar), in two seasons of the year - June(summer in the northern hemisphere) and January (winter in the northernhemisphere). The results of the calculations are given for areas of oceanicCase 1 waters, which cover more than 90% of the volume of all basins inthe World Ocean (according to the optical classification by Morel & Prieur1977). The results of these calculations, though preliminary, providea comprehensive description of the range of variability of theyields / efficiencies of the three deactivation processes. The results havemade it possible to summarize, within the context of the euphotic zone, of thebudgets of phytoplankton pigment molecule excitation energy expended on threecomplementary processes, namely, the fluorescence of chlorophyll a, thephotochemical assimilation of inorganic carbon and the photosynthesis oforganic matter, and the radiationless, nonphotochemical conversion of thepigment molecules' activation energy to heat.

Photoelectrochemical cells have a fundamental problem in that the thin, closely spaced laminar phases normally comprising an electrochemical cell do not readily lend themselves to penetration by external light as part of a solar energy conversion scheme. This has led to novel cell configurations that are more amenable to solar absorption. We are working on a “photocatalytic membrane”, where a single sheet comprised of two semiconductor layers combine their photopotentials to achieve a water-splitting voltage. A schematic depicting how the membrane might be configured is shown below. Light absorption in respective semiconductor layers drives oxidation on one side of the membrane and reduction on the other. Perforations filled with ion-exchange polymer allow the flow of ionic charge carriers (hydronium ion in acidic media) between anolyte and catholyte compartments. To fabricate such a photocatalytic membrane, a sequence of deposition steps must be developed where each subsequent step is compatible with the previous ones. Our strategy is to build n-type and p-type layers on opposite sides of a thin, perforated metallic sheet. A prototype device involving electrodeposition of n-WO3 and p-CdTe on mechanically perforated stainless #304 has been fabricated. A net photovoltage of 0.8 V in aqueous acidic electrolyte was estimated.

To date, solar energy generation devices have been widely studied to meet a clean and sustainable energy source. Among them, water splitting photoelectrochemical cell is regarded as a promising energy generation way for splitting water molecules and generating hydrogen by sunlight. While many nanostructured metal oxides are considered as a candidate, most of them have an improper bandgap structure lowering energy transition efficiency. Herein, we introduce a novel wet-based, successive photoreduction process that can improve charge transfer efficiency by surface plasmon effect for a solar-driven water splitting device. The proposed process enables to fabricate ZnO/CuO/Ag or ZnO/CuO/Au hierarchical nanostructure, having an enhanced electrical, optical, photoelectrochemical property. The fabricated hierarchical nanostructures are demonstrated as a photocathode in the photoelectrochemical cell and characterized by using various analytic tools.

Life on a global biosphere basis is substantiated in the form of organics and organisms, and defined as the intermediate forms (briefly expressed as CH 2 O) hovering between the reduced (CH 4 , methane) and (CO 2 , carbon dioxide) ends, different from the classical definition of life as a complex organization maintaining ordered structure and information. Both definitions consider sustenance of life meant as protection of life against chaos through an input of external energy. The CH 2 O-life connection is maintained as long as the supply of H and O lasts, which is in turn are provided by the splitting of the water molecule H 2 O. Water is split by electricity, as well-known from school-level experiments, and by solar radiation and geothermal heat on a global scale. In other words, the Sun’s radiation and the Earth’s heat as well as radioactivity split water to supply H and O for continued existence of life on the Earth. These photochemical, radiochemical and geothermal processes have influences on the evolution and current composition of the Earth’s atmosphere, compared with those of Venus and Mars, and influences on the planetary climatology. This view of life may be applicable to the “search-for-life in space” and to sustainability assessment of astrobiological habitats.

Random orientation of molecules within a sample leads to blurred observations of chemical reactions studied from the laboratory perspective. Methods developed for the dynamic imaging of molecular structures and processes struggle with this, as measurements are optimally made in the molecular frame. We used laser alignment to transiently fix carbon disulfide molecules in space long enough to elucidate, in the molecular reference frame, details of ultrafast electronic-vibrational dynamics during a photochemical reaction. These three-dimensional photoelectron imaging results, combined with ongoing efforts in molecular alignment and orientation, presage a wide range of insights obtainable from time-resolved studies in the molecular frame.

Naphthalene diimides (NDI) are a class of organic dyes with optical, thermal, and photochemical properties and stability. Hence, its importance in the rapidly developing modern technology, have found expression amongst researchers. NDI interaction with metals is expected to make change in photophysical and photochemical properties of sensitizers such as wavelength shifts and intensity changes in absorption and emission spectra. Consequently, metal complexation of NDI leads to high potential towards organic electronic application. The synthesized compound exhibit different intermolecular interactions in different solvents which enhances its utilization in photonic and optoelectronic application. Therefore, this project aims to synthesize a new NDI dye containing powerful binding site for metal ions. By condensation reaction, NDA and an amine (4,6-diamino-2- pyrimidine-thiol) reacts with isoquinoline and m-cresol solvent mixture in the presence of argon gas. The synthesized product was investigated by IR and UV-vis spectroscopy, TGA and DSC analysis for thermal behavior and elemental analysis. Keywords: Naphthalene diimides. ÖZ: Naftalin diimidler (NDI), optik, ve fotokimyasal özellikleri ve termal kararlılıkları ile bilinen organik boya sınıfındandırlar. Bu nedenle, hızla gelişen modern teknolojide yer almışlar ve araştırmacıların ilgi noktası olmuşlardır. NDI-metal etkileşimi absorpsiyon ve emisyon spektrumları, dalga boyu değişiklikleri gibi fotofiziksel ve fotokimyasal özellikleri de değişiklik yapmabilmektedir. Sonuç olarak, NDI metal kompleksleşmesi organik elektronik uygulamalarına uygun potansiyele sahiptir. Sentezlenmiş bir bileşik değişik çözgenlerde farklı moleküller arası ilişkiler ile fotonik ve optoelektronik özellikleri geliştirir. Bu nedenle, bu proje metal iyonları için güçlü bağlanma bölgesini içeren yeni bir NDI boya sentezlemek amaçlamaktadır. Kondensasyon reaksiyonu, NDA ve bir amin (4,6-diamino-2-pirimidin-tiyol) ile, argon gazı varlığında izokinolin ve m-kresol çözgen karışımında reaksiyona girer. Sentezlenen ürün IR ve UV-vis spektroskopisi ve TGA ve DSC analizi ile karakterize edilmiştir. Anahtar Kelimeler: Naftalin diimidler. Master of Science in Chemistry. Thesis (M.S.)--Eastern Mediterranean University, Faculty of Arts and Sciences, Dept. of Chemistry, 2016. Supervisor: Prof. Dr. Huriye İcil.

This doctoral thesis focuses on the study of laser-induced self-organization of Ag nanoparticles (NPs) in TiO2 thin layers. This laser technique was recently developed to provide original printing solutions for applications like active color displays, security, or polarization imaging. Here, we investigate experimentally and theoretically the different mechanisms involved in the NPs formation for a better control of their morphology and organization. In the case of continuous-wave (cw) laser, our experimental results prove that the speed at which the laser scans the sample surface is a crucial parameter to control the NP size and the laser-induced temperature rise. Ag NPs shrink at low scan speed, whereas growth governed by a thermal effect only occurs above a speed threshold. Above this threshold, the size of grown Ag NPs changes in a non-monotonous way with scan speed, whereas laser-induced temperature rise increases with speed. In order to explain these counter-intuitive behaviors, several numerical models have been developed to simulate changes in the size distribution of Ag NPs induced by visible light. Simulation results are in good agreement with experimental observations and reveal the origin of the observed phenomena by collective interactions of various physico-chemical processes involved in the variation of NPs size. Finally, this thesis demonstrates that self-organization of NPs at sub-wavelength scale on large areas can also be performed with femtosecond (fs) laser pulses. Oriented anisotropic growth of NPs has also been observed using a proper selection of laser irradiation parameters. Compared with the cw laser induced structures, fs pulses offer better control of the thermal effect and NP size, which opens the way to transfer these technologies on plastic or paper substrates, La présente thèse porte sur l’étude de l’auto-organisation induite par laser de nanoparticules (NPs) d’argent dans des couches minces de TiO2. Cette technique laser a été récemment mise au point pour fournir des solutions d'impression originales pour des applications comme l'imagerie polarimétrique, la sécurité ou le design. Ici, nous étudions expérimentalement et théoriquement les différents mécanismes impliqués dans la formation des NPs pour un meilleur contrôle de leur morphologie et de leur organisation. Dans le cas de lasers continus, nos résultats expérimentaux prouvent que la vitesse à laquelle le faisceau laser balaye la surface de l’échantillon est un paramètre crucial pour le contrôle de la taille finale des NPs, et de l’élévation de température induite dans la couche par le laser. La taille des NPs d’argent diminue aux basses vitesses d’écriture, alors que leur croissance est activée par effet thermique et apparait uniquement au-dessus d’un seuil de vitesse. La taille finale des NPs varie dans ce cas de façon non-monotone avec la vitesse de balayage alors que la hausse de température ne cesse de croître. Afin d'expliquer ces phénomènes contre-intuitifs, plusieurs modèles numériques ont été développés qui permettent de simuler la variation de la taille des NPs sous insolation laser dans le domaine spectral du visible. Les résultats théoriques concordent bien avec les observations expérimentales et révèlent que l’origine de ces phénomènes résulte d'interactions complexes entre les différents processus physico-chimiques impliqués dans la formation des NPs. Finalement, cette thèse démontre que l’auto-organisation des NPs à l’échelle sub-longueur d’onde peut être aussi réalisée avec des impulsions laser femto-secondes (fs), et une croissance anisotrope des NPs a été également observée pour une gamme particulière de paramètres laser. La comparaison avec les structures de NPs produites par lasers continus suggère que les impulsions laser fs offrent une meilleure maîtrise des effets thermiques et de la taille des NPs. L'usage de laser fs offre ainsi une nouvelle approche pour transférer ces technologies sur des supports souples comme les papiers ou les plastiques

Thermal and photochemical stability (ΦR), room temperature UV-vis absorption and fluorescence spectra, fluorescence quantum yields (ΦF) and lifetimes (τF), quantum yields of hydrogen peroxide (ΦH2O2) and singlet oxygen (ΦΔ) production, and triplet lifetimes (τT) have been obtained for the neutral and protonated forms of 6-chloroharmine, 8-chloroharmine and 6,8-dichloroharmine, in aqueous media. When it was possible, the effect of pH and oxygen concentration was evaluated. The nature of electronic transitions of protonated and neutral species of the three investigated chloroharmines was established using Time-Dependent Density Functional Theory (TD-DFT) calculations. The impact of all the foregoing observations on the biological role of the studied compounds is discussed., Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas

Ambient air pollution exposure has been associated with several health conditions, limited not only to respiratory and cardiovascular systems but also to cutaneous tissues. However, few epidemiological studies examined pollution exposure on skin problems. Basically, the common mechanism by which pollution may affect skin physiology is by induction of oxidative stress and inflammation. Urticaria is among the skin pathologies that have been associated with pollution. Based on the combined effects of three ambient air pollutants, ozone (O₃), nitrogen dioxide (NO₂), and fine particulate matter (PM) with a median aerodynamic diameter of less than 2.5 μm (PM(2.5)), on mortality, the Air Quality Health Index (AQHI) in Canada was developed. The aim of this study was to examine the associations of short-term changes in AQHI with emergency department (ED) visits for urticaria in Windsor-area hospitals in Canada. Diagnosed ED visits were retrieved from the National Ambulatory Care Reporting System (NACRS). A time-stratified case-crossover design was applied to 2905 ED visits (males = 1215; females = 1690) for urticaria from April 2004 through December 2010. Odds ratios (OR) and their corresponding 95% confidence intervals (95%CI) for ED visits associated with increase by one unit of risk index were calculated employing conditional logistic regression. Positive and significant results were observed between AQHI levels and OR for ED visits for urticaria in Windsor for lags 2 and 3 days. A distributed lag nonlinear model technique was applied to daily counts of ED visits for lags 0 to 10 and significant results were obtained from lag 2 to lag 5 and for lag 9. These findings demonstrated associations between ambient air pollution and urticarial confirming that air pollution affects skin conditions.

Single short-term exposures to ozone are known to cause acute changes in pulmonary function and neutrophilic airway inflammation. The respiratory health effects of repeated exposures are not as well studied. Pulmonary function decrements are known to attenuate, but it is less clear how injury and inflammation are affected. Using sputum induction (SI) to sample respiratory tract lining fluid after single- and multiday exposures, we designed a study to test the hypothesis that neutrophils would increase after multiday exposure compared with single-day exposure. In a randomized, crossover design, 15 normal healthy subjects were exposed to O3 (0.2 ppm) under two conditions: for 4 hr for 1 day (1D) and for 4 hr for 4 consecutive days (4D). Pulmonary function testing was performed immediately before and after each 4-hr exposure. The SI was performed 18 hr after the end of the 1D and 4D conditions. The symptom and pulmonary function data followed a pattern seen in other multiday O3 exposure studies, with the greatest changes occurring on the second day. In contrast to previous studies using bronchoalveolar lavage, however, there was a significant increase in the percentage of neutrophils and a significant decrease in the percentage of macrophages after the 4D condition compared with the 1D condition. Given that SI likely samples proximal airways better than distal lung, these results add to the body of evidence that differential airway compartmental responses to O3 occur in humans and other species.

This paper reviews the influence of hydrophobic pollutant behavior on environmental hazards and risks. The definition and examples of hydrophobic pollutants are given as a guide to better understand the sources of release and the media of dispersion in the environment. The properties and behavior of hydrophobic pollutants are described and their influence on environmental hazard and risk is reviewed and evaluated. The overall outcome of the assessment and evaluation showed that all hydrophobic pollutants are hazardous and risky to all organisms, including man. Their risk effects are due to their inherent persistence, bioaccumulation potential, environmental mobility, and reactivity. Their hazardous effects on organisms occur at varying spatial and temporal degrees of emissions, toxicities, exposures, and concentrations.

A study of indoor air exposures and acute respiratory effects in adults was conducted in the Po Delta (rural) and Pisa (urban) areas of Italy. Indoor exposures were monitored for nitrogen dioxide (NO(2)) and particulate matter2.5 microm (PM(2.5)) for 1 week during the winter or summer in a total of 421 houses (2/3 in Pisa). Information on house characteristics, subjects' daily activity pattern and presence of acute respiratory symptoms was collected by a standardized questionnaire. Peak expiratory flow (PEF) maneuvers were performed by adult subjects four times daily; maximum amplitude and diurnal variation were taken into account. Indices of NO(2) and PM(2.5) exposures were computed as the product of weekly mean pollutant concentration by the time of daily exposure. Mean levels of pollutants were significantly higher in winter than in summer, regardless of the area. The relationship between exposure indices and acute respiratory symptoms was investigated only in winter. In spite of a slightly lower indoor level in the urban than in the rural area in winter (NO(2): 15 vs. 22 ppb; PM(2.5): 67 vs. 76 microg/m(3)), prevalence rates of acute respiratory symptoms were significantly higher in the urban than in the rural area. Acute respiratory illnesses with fever were significantly associated with indices of NO(2) (odds ratio (OR)=1.66; 95% CI=1.08-2.57) and PM(2.5) exposures (OR=1.62; 95% CI=1.04-2.51), while bronchitic/asthmatic symptoms were associated only with PM(2.5) (OR=1.39; 95% CI=1.17-1.66). PEF variability was positively related only to PM(2.5) exposure index (OR=1.38; 95% CI=1.24-1.54, for maximum amplitude; OR=1.37; 95% CI=1.23-1.53, for diurnal variation). In conclusion, indoor pollution exposures were associated with the presence of acute respiratory symptoms and mild lung function impairment in a rural and an urban area of Northern-Central Italy.

Este trabalho versa sobre a caracterização espectroscópica do ácido 1,4-bis(3-carbóxi-3-oxo-prop-1-enil)benzeno, substância com potencialidade em complexação de íons metálicos. Para isto foram obtidos espectros de UV/VIS do composto em meio aquoso na presença e ausência de irradiação no ultra-violeta. Foram obtidos um coeficiente de extinção molar de 36.457 L mol-1 cm-1 e uma taxa de degradação de 5,2.10-7 mol L-1 min-1, quando se irradiou uma solução do composto cuja concentração era de 3,2.10-5 mol L-1 em uma cubeta de quartzo de 10mm de caminho ótico a 7,0cm de uma lâmpada de mercúrio de 80W.This work deals of spectroscopy characterization of the 1,4-bis(3-carboxy-3-oxo-prop-1-enil)benzene acid, a possible metal ion complexant compound. An aqueous solution of the title compound was irradiated using a 80W mercury lamp and the photodegradation was followed by UV/VIS absorption spectra. The molar extinction coefficient determined was 36,457 L mol-1 cm-1 and degradation rate observed was 5.2x10-7 mol L-1 min-1, when the sample was irradiated in a quartz cuvette of 10mm optical path length and distant 7.0cm of the source of light.

The development of methods for specific delivery of drugs is an important issue for many cancer therapy approaches. Most of macromolecular drugs are taken into the cell through endocytosis and, being unable to escape from endocytic vesicles, eventually are degraded there, which hinders their therapeutic usefulness. We have developed a method, called photochemical internalization, based on light-induced photochemical reactions, disrupting endocytic vesicles specifically within illuminated sites e.g. tumours. Here we present a new drug delivery concept based on photochemical internalization-principle – photochemical disruption of endocytic vesicles before delivery of macromolecules, leading to an instant endosomal release instead of detrimental stay of the molecules in endocytic vesicles. Previously we have shown that illumination applied after the treatment with macromolecules substantially improved their biological effect both in vitro and in vivo. Here we demonstrate that exposure to light before delivery of protein toxin gelonin improves gelonin effect in vitro much more than light after. However, in vitro transfection with reporter genes delivered by non-viral and adenoviral vectors is increased more than 10- and six-fold, respectively, by both photochemical internalization strategies. The possible cellular mechanisms involved, and the potential of this new method for practical application of photochemical internalization concept in cancer therapy are discussed. British Journal of Cancer (2002) 86, 652–657. DOI: 10.1038/sj/bjc/6600138 www.bjcancer.com © 2002 Cancer Research UK

Air pollution control in the United States for five common pollutants--particulate matter, ground-level ozone, sulfur dioxide, nitrogen dioxide, and carbon monoxide--is based partly on the attainment of ambient air quality standards that represent a level of air pollution regarded as safe. Regulatory and health agencies often focus on whether standards for short periods are attained; the number of days that standards are exceeded is used to track progress. Efforts to explain air pollution to the public often incorporate an air quality index that represents daily concentrations of pollutants. While effects of short-term exposures have been emphasized, research shows that long-term exposures to lower concentrations of air pollutants can also result in adverse health effects. We developed an aggregate index that represents long-term exposure to these pollutants, using 1995 monitoring data for metropolitan areas obtained from the U.S. Environmental Protection Agency's Aerometric Information Retrieval System. We compared the ranking of metropolitan areas under the proposed aggregate index with the ranking of areas by the number of days that short-term standards were exceeded. The geographic areas with the highest burden of long-term exposures are not, in all cases, the same as those with the most days that exceeded a short-term standard. We believe that an aggregate index of long-term air pollution offers an informative addition to the principal approaches currently used to describe air pollution exposures; further work on an aggregate index representing long-term exposure to air pollutants is warranted.

New emerging contaminants could represent a danger to the environment and Humanity with repercussions not yet known. One of the major worldwide pharmaceutical and personal care productions are antimicrobials products, triclosan, is an antimicrobial agent present in most products. Despite the high removal rate of triclosan present in wastewater treatments, triclosan levels are on the rise in the environment through disposal of wastewater effluent and use of sewage sludge in land application. Regulated in the EC/1272/2008 (annex VI, table 3.1), this compound is considered very toxic to aquatic life and it has been reported that photochemical transformation of triclosan produces dioxins. In the current work it was defined three objectives; determination of the most efficient process in triclosan degradation, recurring to photochemical degradation methods comparing different sources of light; identification of the main by-products formed during the degradation and the study of the influence of the Fenton and photo-Fenton reaction. Photochemical degradation methods such as: photocatalysis under florescent light (UV), photocatalysis under visible light (sunlight), photocatalysis under LEDs, photo-Fenton and Fenton reaction have been compared in this work. The degradation of triclosan was visualized through gas chromatography/mass spectrometry (GC/MS). In this study photo-Fenton reaction has successfully oxidized triclosan to H2O and CO2 without any by-products within 2 hours. Photocatalysis by titanium dioxide (TiO2) under LEDs was possible, having a degradation rate of 53% in an 8 hours essay. The degradation rate of the Fenton reaction, UV light and sunlight showed degradation between 90% and 95%. The results are reported to the data observed without statistic support, since this was not possible during the work period. Hydroquinone specie and 2,4-dichlorophenol by-products were identified in the first hour of photocatalysis by UV. A common compound, possibly identified has C7O4H , was present at the degradation by UV, sunlight and LEDs and was concluded to be a contaminant. In the future more studies in the use of LEDs should be undertaken given the advantages of long durability and low consumption of energy of these lamps and that due to their negative impact on the environment fluorescent lamps are being progressively made unavailable by governments, requiring new solutions to be found. Fenton and photo-Fenton reactions can also be costly processes given the expensive reagents used.

Organic crystals are found in everyday goods such as foods, drugs, dyes, and agricultural products. To better understand the solid-state behaviour of organic crystals, the study of their surfaces is crucial, as several reactions occur at the interface between the crystal surface and its immediate environment. While atomic force microscopy (AFM) is a useful tool for studying surfaces, it is not a common technique for studying organic crystals. The rst part of this report aims to address problems of imaging organic crystals by AFM which arise from the nature of the imaging technique and the material property of organic crystals. Methods of detecting and predicting the likelihood of the problems encountered in imaging organic crystals are suggested in order for a more accurate interpretation of the information obtained by this technique. The e ect of humidity on aspirin crystal surfaces is then investigated by AFM. The growth of new features on the surface is believed to be a result of the hydrolysis of aspirin molecules. Mechanisms are suggested based on the observed surface response of aspirin, where surface defects and the mobility of surface molecules are believed to be important factors a ecting reactivity. The last section investigates the solid-state photochemical reaction of anthracene, which is a reaction that should not occur according to the topochemical postulate. The surface response of anthracene crystals to UV light was studied, and the results indicate strong reactivity at sites of surface defects, which is likely due to photodimerisation. A similar mechanism that described the behaviour of aspirin surfaces was suggested for this reaction. In summary, both reactions that were studied provided a better insight towards understanding the solid-state reactivity of organic crystals. The proposed surface mechanisms imply that surface defects and the presence of humidity or solvent vapour are very likely to play a role in determining reactivity. Further studies on the origin of defects are suggested in order to better control the behaviour of organic crystals in the solid-state., Pfizer Institute of Pharmaceutical Materials Science

The metallization of TiO 2 photocatalyst with 1%Pt gave increasing rates of alcohol conversions and carbon dioxide production. A new porous powder micro-cell model was proposed. Heterogeneous reactions of photocatalytic oxidation, and final mineralizing to CO 2 , of methanol, ethanol in dilute (50–400 pm) aqueous solution should take place on the solid–liquid interface of the photocatalyst. It has similar kinetic behavior as reactions on the solid–gas interface of a heterogeneous catalyst. The process can be described by the Langmuir adsorption isotherm. These photocatalytic degradations can be expressed as a first-order reaction. Maximum rates of photocatalytic reactions and efficiencies can be estimated according to the calculation of surface coverage of certain compounds on TiO 2 . Because ethanol have the double coverage of methanol at same concentration, it is presumed that methanol and ethanol have the same adsorption state of the end-group on catalyst surfaces. In a closed reactor, if oxygen pressure was controlled at 76 cm H 2 O, its reduction rate was nearly of zero order.