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A modification of the MCM-41 mesoporous materials through carbon deposition followed by acid washing has been studied for application in carbon dioxide adsorption. Two routes were used to prepare pure silica (Si-MCM-41) and Al-containing (Al-MCM-41) samples, through hydrothermal synthesis at 150 °C for 24 h. The post-synthesis treatment took place in two stages: carbon deposition using commercial glucose, in the mass ratio of 1 g (support): 2.2 g (glucose): 3.5 g (water), followed by washing with 0.2 M hydrofluoric acid solution at 65 °C for 2 h. The samples were characterized by X-ray diffraction, dispersive energy X-ray spectrometry, nitrogen adsorption–desorption, Fourier-transform infrared spectroscopy, thermal analyzes, and scanning electron microscopy. CO2 adsorption tests were performed on a thermogravimetric balance at 40 °C under atmospheric pressure. Carbon deposition led to a drastic reduction in the surface area and pore volume values of MCM-41 samples, possibly due to deposits of carbonaceous species blocking part of the mesopores and defect sites in the pore wall as self-assembled monolayers. After acid washing, part of these deposits was removed, as well as the occurrence of structural silicon leaching. The post-synthesis treatment allowed the generation of structures with a bimodal pore system, providing a substantial increase in the CO2 adsorption capacity compared to the as-synthesized mesoporous materials (~66% for pure silica and 44% for Al-containing MCM-41 sample), representing a significant improvement in the adsorbents performance for CO2 capture.

The thermo-catalytic degradation of polyethylene (PE) and ultra-high molecular weight polyethylene (UHMWPE) was studied in the presence of zeolites (ZSM-5, ZSM-22, and ferrierite) with different pore systems and textural properties. The zeolites were physically mixed with polymers in the proportion of 30 wt% and submitted to thermogravimetric analysis at heating rates of 5, 10, 20, and 30 °C.min-1. The activation energy of the degradation process was determined using the Flynn-Wall-Ozawa method. The addition of zeolites to polymers has considerably reduced the temperature of degradation. ZSM-22 demonstrated greater efficiency in the degradation of PE because it has a smaller crystallite size, promoting a shorter diffusional path for the polymer fragments coming from the surface. Ferrierite showed a lower energy level in the degradation of UHMWPE, showing the need for synergy between the accessibility of the structure and acidity of the catalyst to promote the cracking of this polymer.

The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fcimb.2021.779376/full#supplementary-material, Bacterial vaginosis (BV) is the most common vaginal infection in women of reproductive age and has been associated with serious health complications, mainly in pregnant women. It is characterized by a decrease in the number of Lactobacillus species in the healthy vaginal microbiota and an overgrowth of strict and facultative anaerobic bacteria that develop a polymicrobial biofilm. Despite over 60 years of research investigating BV, its etiology is not fully understood. Gardnerella spp. is a crucial microorganism that contributes to the formation of the biofilm and the development of BV, but the role of other BV-associated bacteria is not clear. Nevertheless, Fannyhessea vaginae (previously known as Atopobium vaginae) is a highly specific species for BV, and co-colonization with Gardnerella is thought to be a very specific diagnostic marker. The diagnosis of BV still presents some limitations, since currently used methods often fail to accurately detect BV. This work aims to develop a novel peptide nucleic acid (PNA) probe targeting F. vaginae. This probe was further validated in a multiplex assay, which included a Gardnerella-specific PNA probe, as a possible method for diagnosis of BV, and was compared with quantification by qPCR. The new PNA probe showed excellent sensitivity and specificity and could discriminate F. vaginae-Gardnerella biofilms, confirming the potential to be used for the detection of BV-associated pathogens., This work was funded by the National Institute of Allergy and Infectious Diseases (R01AI146065-01A1). It was also partially funded by the Portuguese Foundation for Science and Technology (FCT), under the scope of the strategic funding of unit (UIDB/04469/2020)., info:eu-repo/semantics/publishedVersion

DNA is one of the most exciting biomolecules in nature for developing supramolecular biofunctional nanoarchitectures owing to the highly specific and selective interactions between complementary Watson-Crick base pairing. Herein, simple and one-pot synthetic procedures have been implemented for producing a library of DNA nucleobase derivatives endowed with reactive functional groups for bioconjugation and cross-linking strategies with other (bio)molecules. Purine and pyrimidine molecules have been regioselectively N−H functionalized either viaN-alkylation,N-allylation,N-propargylation or Michael-type reactions and structurally characterized. The influence of the reaction conditions was assessed and discussed. The in vitro biocompatibility of the native and nucleobase derivatives was evaluated by culturing them with human fibroblasts, revealing their cytocompatibility. The library of nucleobase derivatives holds great promise for being coupled to different biomolecules, including biopolymeric materials, lipids, and peptides, thus potentially leading to modular supramolecular nanobiomaterials for biomedicine. One-pot synthetic procedures for producing a library of nucleobase derivatives enlisted with reactive functional groups for bioconjugation and cross-linking reactions with other biomolecules are reported. The nucleobase derivatives bearing eitherN-alkyl,N-propanenitrile,N-allyl orN-propargyl terminals are non-cytotoxic, denoting great promise for biomedical applications.

The synthesis of SSZ-13 was studied by evaluating the influence of two types of crystallization seeds with CHA structure (S1 seeds prepared in fluoride medium and S2 seeds by the conversion of zeolite Y), SiO2/Al2O3 (28, 40, 60 and 100) and OH/SiO2 (0.6 and 0.8) ratios. Choline chloride was used as the structure-directing agent and the crystallizations occurred at 140 ºC from 24 to 96 h. S1 seeds led to the coexistence of zeolites SSZ-13 and P, while S2 seeds promoted in all SiO2/Al2O3 ratios and OH/SiO2 = 0.8, the formation of pure SSZ-13 after 24 h. The SSZ-13 samples are formed by clusters of crystals with cuboid-like morphology and exhibited textural properties typical of CHA framework. SSZ-13 zeolite led to a decrease in the temperature and the activation energy required for the degradation of ultra-high molecular weight polyethylene polymer, demonstrating its efficiency as catalyst in this process.

Hydrotalcite-like materials were synthesized by pH-controlled precipitation method with Ni2+ and Al3+ cations and terephthalate as the compensation anion. Ni/Al ratios were 1.0 and 0.3, both high in aluminum content for what has been commonly reported in the literature for this type of materials. The incorporation of Zr(IV) in the structure of the materials was evaluated substituting Al(III) for Zr(IV), using Al/Zr ratios of 3.0 and 0.3. Characterization techniques, such as X-ray diffraction, thermogravimetric analysis, infrared spectroscopy and chemical analysis, demonstrated that NiAlZr-terephthalate hydrotalcite-like materials were obtained simultaneously with amorphous phases of ZrO2 and Al(OH)3. The mixed oxides, produced by the calcination of the hydrotalcites, had interesting characteristics that could be useful for potential unsupported mesoporous nickel catalysts, with high surface areas, nanoparticles, variable reducibility temperature, thermal stability and different kinds of interaction of nickel with aluminum and zirconium, depending on the metal content. These NiAlZr oxides were evaluated as catalysts for cyclohexane dehydrogenation reaction after a reduction process. The resulting catalysts presented a high cyclohexane conversion and in some cases selectivity to benzene close to 90%, especially when zirconium was added and nanosized cristallites of NiO were formed.

Proteomics and physiological approaches reveal that peroxisomal APX silencing and CAT inhibition trigger H2O2-signalling for up-regulation of antioxidant proteins to protect the rice photosynthetic apparatus under oxidative stresss., Retrograde signalling pathways that are triggered by changes in cellular redox homeostasis remain poorly understood. Transformed rice plants that are deficient in peroxisomal ascorbate peroxidase APX4 (OsAPX4-RNAi) are known to exhibit more effective protection of photosynthesis against oxidative stress than controls when catalase (CAT) is inhibited, but the mechanisms involved have not been characterized. An in-depth physiological and proteomics analysis was therefore performed on OsAPX4-RNAi CAT-inhibited rice plants. Loss of APX4 function led to an increased abundance of several proteins that are involved in essential metabolic pathways, possibly as a result of increased tissue H2O2 levels. Higher photosynthetic activities observed in the OsAPX4-RNAi plants under CAT inhibition were accompanied by higher levels of Rubisco, higher maximum rates of Rubisco carboxylation, and increased photochemical efficiencies, together with large increases in photosynthesis-related proteins. Large increases were also observed in the levels of proteins involved in the ascorbate/glutathione cycle and in other antioxidant-related pathways, and these changes may be important in the protection of photosynthesis in the OsAPX4-RNAi plants. Large increases in the abundance of proteins localized in the nuclei and mitochondria were also observed, together with increased levels of proteins involved in important cellular pathways, particularly protein translation. Taken together, the results show that OsAPX4-RNAi plants exhibit significant metabolic reprogramming, which incorporates a more effective antioxidant response to protect photosynthesis under conditions of impaired CAT activity.

Marine traffic has been identified as a relevant source of pollutants, which cause known negative effects on air quality. The Iberian Peninsula is a central point in the connection of shipping traffic between the Americas, Africa, and the rest of Europe. To estimate the effects of shipping emissions inland and around the Iberian Peninsula, the EMEP/MSC-W model was run considering and not considering shipping emissions (obtained with STEAM3). Total estimated emissions of CO, CO2, SOx, NOx, and particulate matter (subdivided into elementary carbon – EC, organic carbon – OC, sulfate, and ash) for the study domain in 2015 were respectively 49, 30 000, 360, 710, 4.5, 11, 32, and 3.3 kt yr−1. Shipping emissions increased SO2 and NO2 concentrations, especially near port areas, and also increased the O3, sulfate, and particulate matter (PM2.5 and PM10) concentrations over the entire Iberian Peninsula coastline (especially in the south coastal region). Shipping emissions were responsible for exceedances of WHO air quality guidelines for PM2.5 in areas far from the coastline, which confirms that shipping emissions can contribute negatively to air quality, both in coastal and inland areas.

This is a study of the fast synthesis of ZSM-22 zeolite using crystallization seeds and a cheap source of silica. The effect of crystallization time, addition of methanol as organic solvent, SiO2/Al2O3 ratio (SAR), alkalinity (OH−/SiO2 ratio), addition of potassium cation, and agitation were studied on the properties of the produced zeolite. Syntheses were performed at 170 °C with a fixed seed:SiO2 mass ratio of 10%. The seeds were synthesized by the hydrothermal method at 160 °C in the presence of 1,6-diaminohexane organic template. Products were characterized using X-ray diffraction, thermal analysis, nitrogen adsorption at −196 °C, and scanning electron microscopy. Under static conditions the best result was reached after 6 h of crystallization, obtaining a ZSM-22 with 80% crystallinity, in the presence of methanol, low alkalinity, without addition of K+ and SAR 100. The synthesis of ZSM-22 with SAR 50 using the same method resulted in a slightly lower crystallinity than with SAR 100. The increase in alkalinity or potassium concentration in the synthesis reaction medium decreased the crystallinity of the zeolite. Synthesis with the same composition under agitated condition increased the crystallinity and specific surface area of the zeolite and decreased reaction time from 6 to 4 h. The fastest synthesis was obtained under agitation with low methanol content in the reaction medium, obtaining the ZSM-22 structure after 3 h of reaction with higher crystallinity and surface area. The importance of fast synthesis is to reduce the cost of the zeolite production.

Air pollution is the leading cause of the global burden of disease from the environment, entailing substantial economic consequences. International shipping is a significant source of NOx, SO2, CO and PM, which contributes to the increase in O3 levels that can cause known negative health impacts. Thus, this study aimed to estimate the health impacts of ozone ship-related air pollution in Portugal in 2015. To determine the health-related effects of this sector, shipping emissions were obtained from an Automatic Identification System based emission inventory using the Ship Traffic Emission Assessment Model (STEAM). Their contributions to SOMO35 (sum of ozone daily 8-h maximum means over 35 ppb in the calendar year, expressed in ppb per day) levels in Portugal were modelled using the EMEP/MSC-W chemistry transport model (simulations with and without shipping emissions). Log-linear functions based on WHO-HRAPIE relative risks for each health endpoint (all-cause and respiratory mortality, and cardiovascular and respiratory hospital admissions) were used to estimate the attributable fractions. Then, the excess burden of disease was calculated by multiplying the attributable fractions with the baseline incidence of each health endpoint and the population at LAU2 level. Costs associated with the health impacts were estimated as the product of the excess burden of disease and its unit health cost value. Shipping emissions contributed to an increase of 21% in the number of deaths for all-cause mortality and respiratory diseases, as well as hospital admissions for cardiovascular and respiratory diseases. A total external cost of around 180 (86-266) M€ a yr-1 was estimated for these health endpoints in 2015. These results show that O3-related air pollution from ships is a considerable problem affecting the Portuguese population. (c) 2019 WIT Press

The physiological role of plant mitochondrial glutathione peroxidases is scarcely known. This study attempted to elucidate the role of a rice mitochondrial isoform (GPX1) in photosynthesis under normal growth and salinity conditions. GPX1 knockdown rice lines (GPX1s) were tested in absence and presence of 100 mM NaCl for 6 d. Growth reduction of GPX1s line under non-stressful conditions, compared with non-transformed (NT) plants occurred in parallel to increased H2 O2 and decreased GSH contents. These changes occurred concurrently with photosynthesis impairment, particularly in Calvin cycle's reactions, since photochemical efficiency did not change. Thus, GPX1 silencing and downstream molecular/metabolic changes modulated photosynthesis differentially. In contrast, salinity induced reduction in both phases of photosynthesis, which were more impaired in silenced plants. These changes were associated with root morphology alterations but not shoot growth. Both studied lines displayed increased GPX activity but H2 O2 content did not change in response to salinity. Transformed plants exhibited lower photorespiration, water use efficiency and root growth, indicating that GPX1 could be important to salt tolerance. Growth reduction of GPX1s line might be related to photosynthesis impairment, which in turn could have involved a cross talk mechanism between mitochondria and chloroplast originated from redox changes due to GPX1 deficiency.

The synthesis of ZSM-23 zeolite was studied using isopropylamine, ethylene glycol, pyrrolidine and N,N-dimethylformamide as structure-directing agents, followed by post-synthesis treatment. The samples were characterized by X-ray diffraction (XRD), dispersive energy X-ray spectroscopy (EDX), thermal analysis, adsorption-desorption of nitrogen, temperature programmed desorption of ammonia (TPD-NH3) and scanning electron microscopy (SEM). ZSM-23 was obtained with all organic molecules tested, and the sample synthesized with isopropylamine presented a higher crystallinity. EDX measurements indicated parent zeolites with SiO2/Al2O3 ratio ≥66. Thermal analysis curves showed that the parent sample prepared with isopropylamine presented lower mass loss, corroborating the crystallinity results and indicating a greater efficiency of this compound in the ZSM-23 synthesis. Micrographs of the parent samples synthesized with isopropylamine, ethylene glycol and N,N-dimethylformamide illustrated the characteristic morphology of ZSM-23 as “needles”, whereas the sample obtained with pyrrolidine showed the coexistence of ZSM-23 and ZSM-5 phases. TPD-NH3 results demonstrated that the post-synthesis treatment promoted, in all cases, a decrease in the weak acid sites and an increase in the strong and total acid sites densities for the samples from the isopropylamine and N,N-dimethylformamide series. Adsorption-desorption of nitrogen showed an increase in pore volume and specific surface area values for the modified samples compared to the parent materials. Modified zeolites presented higher catalytic activity and better deactivation resistance in n-heptane catalytic cracking in comparison to the precursor samples, with all catalysts showing excellent selectivity for propene and ethene.

The physiological role of peroxisomal ascorbate peroxidases (pAPX) is unknown; therefore, we utilized pAPX4 knockdown rice and catalase (CAT) inhibition to assess its role in CAT compensation under high photorespiration. pAPX4 knockdown induced co-suppression in the expression of pAPX3. The rice mutants exhibited metabolic changes such as lower CAT and glycolate oxidase (GO) activities and reduced glyoxylate content; however, APX activity was not altered. CAT inhibition triggered different changes in the expression of CAT, APX and glutathione peroxidase (GPX) isoforms between non-transformed (NT) and silenced plants. These responses were associated with alterations in APX, GPX and GO activities, suggesting redox homeostasis differences. The glutathione oxidation-reduction states were modulated differently in mutants, and the ascorbate redox state was greatly affected in both genotypes. The pAPX suffered less oxidative stress and photosystem II (PSII) damage and displayed higher photosynthesis than the NT plants. The improved acclimation exhibited by the pAPX plants was indicated by lower H2 O2 accumulation, which was associated with lower GO activity and glyoxylate content. The suppression of both pAPXs and/or its downstream metabolic and molecular effects may trigger favourable antioxidant and compensatory mechanisms to cope with CAT deficiency. This physiological acclimation may involve signalling by peroxisomal H2 O2 , which minimized the photorespiration.

This paper aims: (i) to analyse the influence of ozone precursors (both meteorological variables and pollutant concentrations) on ozone concentrations at different ozone levels; and (ii) to predict next day hourly ozone concentrations using a new approach based on quantile regression (QR). The performance of this model was compared with multiple linear regressions (MLR) for the three following periods: daylight, night time and all day. QR as proven to be an useful mathematical tool to evidence the heterogeneity of ozone predictor influences at different ozone levels. Such heterogeneity is generally hidden when an ordinary least square regression model is applied. The influence of previous concentrations of ozone and nitrogen monoxide on next day ozone concentrations was higher for lower quantiles. When QR was applied, the wind direction (WD) was found to be significant in the medium quantiles and the relative humidity (RH) in the higher quantiles. On the contrary, using the MLR models, both variables were not statistically significant. Moreover, QR allowed more efficient previsions of extreme values which are very useful once the forecasting of higher concentrations is fundamental to develop strategies for protecting the public health. Copyright © 2008 John Wiley & Sons, Ltd.

High concentrations of near-surface ozone are known to have negative impacts on human health, especially among risk groups such as persons with respiratory problems, children, and the elderly. The aim of this work was to identify regions with high ozone concentrations and very low concentrations of other pollutants, where further studies will be performed regarding the specific impact of ozone on childhood asthma. For that, the concentrations of ozone and of its precursors at remote areas were assessed and compared with those observed at an urban area influenced by traffic. Measurements using passive samplers were compared with those performed with continuous monitors and it was possible to conclude that measurements with passive samplers had satisfactory reproducibility and precision. For O3, the comparison of both methods showed a maximum absolute difference of +4.10 μ g.m−3 and relative differences lower than −8.8%. The maximum absolute difference for NO2 was +5.2 μ g.m−3 and the relative diff...

This paper describes a proteome analysis and changes in endogenous abscisic acid (ABA) contents during seed development of Araucaria angustifolia (Bert.) O. Ktze. Megagametophytes and embryonic axis tissues exhibited a similar ABA variation pattern during seed development, reaching maximum values at the pre-cotyledonary stage. The embryonic axis protein content increased until the cotyledonary stage with following stabilization at mature seed. The two-dimensional electrophoresis at the torpedo developmental stage showed approximately 230 polypeptides against 340 in the mature stage. Peptide mass fingerprinting analyses identified three polypeptides, corresponding to an AtSAC4, a late embryogenesis abundant (LEA) and a storage protein, respectively.

The prediction of tropospheric ozone concentrations is very important due to the negative impacts of ozone on human health, climate and vegetation. The development of models to predict ozone concentrations is thus very useful because it can provide early warnings to the population and also reduce the number of measuring sites. The aim of this study was to predict next day hourly ozone concentrations through a new methodology based on feedforward artificial neural networks using principal components as inputs. The developed model was compared with multiple linear regression, feedforward artificial neural networks based on the original data and also with principal component regression. Results showed that the use of principal components as inputs improved both models prediction by reducing their complexity and eliminating data collinearity.

This study, Part II of the larger study "Children's exposure to indoor air in urban nurseries", aimed to: (i) evaluate nursery schools' indoor concentrations of several air pollutants in class and lunch rooms; and (ii) analyse them according to guidelines and references. Indoor continuous measurements were performed, and outdoor concentrations were obtained to determine indoor/outdoor ratios. The influence of outdoor air seemed to be determinant on carbon monoxide (CO), nitrogen dioxide (NO2) and ozone (O-3) indoor concentrations. The peak concentrations of formaldehyde and volatile organic compounds (VOC) registered (highest concentrations of 204 and 2320 mu g m(-3) respectively), indicated the presence of specific indoor sources of these pollutants, namely materials emitting formaldehyde and products emitting VOC associated to cleaning and children's specific activities (like paints and glues). For formaldehyde, baseline constant concentrations along the day were also found in some of the studied rooms, which enhances the importance of detailing the study of children's short and long-term exposure to this indoor air pollutant. While CO, NO2 and O-3 never exceeded the national and international reference values for IAQand health protection, exceedances were found for formaldehyde and VOC. For this reason, a health risk assessment approach could be interesting for future research to assess children's health risks of exposure to formaldehyde and to VOC concentrations in nursery schools. Changing cleaning schedules and materials emitting formaldehyde, and more efficient ventilation while using products emitting VOC, with the correct amount and distribution of fresh air, would decrease children's exposure.

The performance of three statistical methods: time-series, multiple linear regression and feedforward artificial neural networks models were compared to predict the daily mean ozone concentrations. The study here reported was based on data from one urban site with traffic influences and one rural background site. The studies were performed for the year 2002 and the respective four trimesters separately. In the multiple linear regression and feedforward artificial neural network models, the concentrations of ozone, the concentrations of its precursors (nitrogen oxides) and some meteorological variables for one and two days before the prediction day were used as predictors. For the application of these models in the validation step, the inputs of ozone concentration for one and two days before were replaced by the ozone concentrations predicted by the models. The results showed that time-series modelling was not profitable. In the development step, similar performances were obtained with multiple linear regression and feedforward artificial neural network. Better performance indexes were achieved with feedforward artificial neural network models in validation step. Concluding, feedforward artificial neural network models were more efficient to predict ozone concentrations.

The main purpose of this study was to evaluate the contribution of anthropogenic pollutants to the increase of tropospheric ozone levels in the Oporto Metropolitan Area (Portugal) since the 19th century. The study was based on pre-industrial and recent data series, the results being analyzed according to the atmospheric chemistry. The treatment of ozone and meteorological data was performed by classical statistics and by time-series analysis. It was concluded that in the 19th century the ozone present in the troposphere was not of photochemical origin, being possible to consider the respective concentrations as reference values. For recent data a cycle of 8 h for ozone concentrations could be related to traffic. Compared to the 19th century, the current concentrations were 147% higher (252% higher in May) due to the increased photochemical production associated with the increased anthropogenic emissions.

The toxicity of octamethylcyclotetrasiloxane (OMCTS) to representative freshwater and marine fish and invertebrates was investigated. Testing procedures followed Toxic Substance Control Act (TSCA) guidelines with chemical-specific adaptations as presented in the OMCTS Testing Consent Order (Docket OPTS-42071A). The physicochemical properties and behavior of OMCTS (i.e., high volatility, low water solubility) precluded the use of conventional experimental practices and exposure systems. Procedures and systems developed during these investigations provided a mechanism that produced exposure levels equal to the maximum achievable (i.e., “functional”) solubility of OMCTS in natural dilution waters. The toxicant delivery systems and exposure chambers were designed to minimize volatilization by elimination of the air/water interface. The flow-through systems maintained consistent exposure concentrations and adhered to U.S. Environmental Protection Agency (EPA) Guideline test performance criteria. The “functional” water solubility of OMCTS in freshwater and seawater ranged from 14 to 30 μg/L and from 6.0 to 9.0 μg/L, respectively. Functional water solubility appeared to vary slightly with test conditions and dilution water characteristics. Continuous exposures of 2 to 93 d were conducted during these investigations with daphnids (Daphnia magna), rainbow trout (Oncorhynchus mykiss), mysids (Mysidopsis bahia), and sheepshead minnow (Cyprinodon variegatus). The rainbow trout was determined to be the most sensitive species to OMCTS (14-d LC50 = 10 μg/L). At levels equal to the functional water solubility, OMCTS was not acutely toxic to D. magna, mysids, or sheepshead minnow. The survival of D. magna was reduced by 16%, relative to the control organisms, after 21-d exposures to 15 μg/L OMCTS; exposure to 7.9 μg/L OMCTS or less had no effect on daphnid survival or reproduction. No toxicity was observed at the highest concentration tested in a 93-d exposure of rainbow trout early life stages. The no-observed-effect concentration for this study was 4.4 μg/L, the same as determined in a 14-d extended acute study.

This paper proposes an automatic method for estimating the location of the optic disc in color images of the retina. The proposed methodology is founded in a new concept, the entropy of vascular directions, which proved to be a reliable measure for assessing the convergence of vessels around an image point. To improve the robustness of the method, the search for the maximum value of entropy is restricted to image areas with high intensity. This new method was evaluated in two publicly available databases, containing both normal and pathological images, and was able to obtain a valid location for the optic disc in 115 out of the 121 images of the two datasets.

The aim of this study was: (i) to predict next day hourly ozone concentrations, for an urban site with traffic influence located at Oporto, by applying principal component regression (PCR); and (ii) comparing PCR with multiple linear regression (MLR). The use of principal components as inputs in the models improved the O 3 concentrations prediction.

International audience; The cross-plane thermal conductivity of Ge$_2$Sb$_2$Te$_5$, either in its amorphous state or fcc crystallized state, and titanium nitride (TiN) thin films has been measured at room temperature by the 3 omega method. These materials are involved in the fabrication of phase change random access memory (PC -RAM) Ge$_2$Sb$_2$Te$_5$ and TiN being the PC and pseudoelectrode materials, respectively. The thermal conductivity of insulating SiO$_2$ and ZnS:SiO$_2$ layers was determined too. Each thermal conductivity measurement was performed by the means of at least two strip widths in order to check both the measurement self-consistency and the measurement accuracy. The performance of PC-RAM cells, i.e., the time needed to reach the melting temperature of the PC material and the cooling speed, has been evaluated as a function of both the measured thermal conductivity of the PC material and the reset current intensity independently of the thermal properties of the pseudoelectrodes by the way of analytical formula. The influence of the thickness and the thermal properties of the pseudoelectrodes on the performances have been determined by numerical simulations.

Sometimes nocturnal ozone maxima have been observed, contrasting with the nocturnal minimum values of typical daily profile. The influence of land-sea breeze on the nocturnal ozone maxima was analysed in two urban sites strongly influenced by traffic emissions. Results showed that the increase in nocturnal ozone concentration, as well as its maxima was caused by horizontal advection of ozone, associated with the development of land-sea breezes. This conclusion, obtained considering 18 months of two years, is in agreement with the only previous study that analysed the influence of land-sea breeze, but considering simply the four warmest months of one year.

Nutritional status is essential for the determination of mammalian reproductive performance, and insulin is one of the main indicators for such condition. This hormone is able to interfere, directly or indirectly, with CL function, leading to alterations in steroidogenic capacity and cell development and, consequently, early embryonic development. The aim of this work was to identify CL histological alterations caused by different insulin plasma concentrations in superovulated ewes, as well as their interference in CL progesterone production. Santa Inês ewes (n = 24, 4 years old) were divided into 3 treatments: control (T1, n = 9); hypoinsulinemic (T2, n = 6), and hyperinsulinemic (T3, n = 9). In order to become hypoinsulinemic, ewes were treated with a single dose of alloxan monohydrate (50 mg kg-1 i.v; Sigma-Aldich, St. Louis, MO, USA) 48 h before the beginning of the superovulation protocol, whereas the hyperinsulinemic group was treated with administrations of 20 IU of NPH human insulin at every 12 h (Biolin-N; BIOBRAS, Montes Claros, Brazil). All animals were fed corn silage and minerals ad libitum. Animals had their estrus synchronized with vaginal pessaries containing medroxyprogesterone acetate (60 mg) and were superovulated with porcine FSH (250 IU, PLUSET®, Calier, Spain) and eCG (250 IU, Novormon®, Schering-Plough, Kenilworth, NJ, USA), in a 13-day protocol. After removal of vaginal pessaries, blood samples used for quantification of progesterone and plasmatic insulin by radioimmunoassay were collected daily at 0700 h until the day before embryo recovery. Hysterectomy was performed in all groups after embryo recovery (T1: n = 3, T2: n = 6, and T3: n = 4), and ovaries were placed in buffered formalin saline. CL histological sections were evaluated by hematoxylin/eosin staining. Results were assessed by SAS statistical analysis software, using the MIXED procedure (SAS Institute Inc., Cary, NC, USA). Mean values were compared by Tukey’s test. The mean CL number was lower in T2 (5.0 ± 2.7; P < 0.05) compared with T1 (10.2 ± 5.1) and T3 (11.3 ± 3.0) animals. No histological differences were observed between treatments T1 and T3. However, CL within the T2 group had a higher number of cells with picnotic nuclei and strongly contracted eosinophilic cytoplasm. Such alterations are suggestive of cellular apoptosis. The T2 group also differed for P4 production (P < 0.01) from the second (T2: 2.23 ± 0.71 ηg mL-1; T1: 5.42 ± 4.01 ηg mL-1; T3: 6.44 ± 2.76 ηg mL-1) to the sixth day post-estrus (T2: 7.58 ± 7.00; T1: 24.79 ± 8.40; T3: 32.07 ± 0.85 ηg mL-1). The mean insulin plasma concentration differed between treatments (P < 0.01); higher concentrations were obtained in the T3 group (20.05 ± 7.50 μIU mL-1), whereas the T2 group had lower concentrations (10.18 ± 3.57 μIU mL-1) compared to controls (T1: 14.52 ± 3.80 μIU mL-1). In conclusion, low plasma concentration of insulin may restrict the response to superovulatory treatment and cause CL histological changes, suggesting a reduction in cell activity due to premature cellular senescence.