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To unveil and shape the molecular connectivity in (metallo)porphyrin-carbon nanotube hybrids are of main relevance for the multiple medicinal, photoelectronic, catalytic, and photocatalytic applications of these materials. Multi-walled carbon nanotubes (MWCNTs) were modified through 1,3-dipolar cycloaddition reactions with azomethine ylides generated in situ and carrying pentafluorophenyl groups, followed by immobilization of the ß-amino-tetraphenylporphyrinate Zn(II). The functionalities were confirmed via XPS and FTIR, whereas Raman spectroscopy showed disruptions on the graphitic carbon nanotube surface upon both steps. The functionalization extension, measured via TGA mass loss and corroborated via XPS, was 0.2 mmol·g-1. Photophysical studies attest to the presence of the different porphyrin-carbon nanotube connectivity in the nanohybrid. Significantly different emission spectra and fluorescence anisotropy of 0.15-0.3 were observed upon variation of excitation wavelength. Vis-NIR absorption and flash photolysis experiments showed energy/charge transfer in the photoactivated nanohybrid. Moreover, evidence was found for direct reaction of amino groups with a carbon nanotube surface in the presence of molecular dipoles such as the zwitterionic sarcosine amino acid.
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Raman spectroscopy is highly sensitive to the morphology and electronic structures of graphitic materials, but a convenient interpretation model has been lacking for multiwalled carbon nanotubes (MWCNTs), in particular for the discrimination of spectral changes induced by covalent functionalization. The present work describes a systematic investigation of the Raman analysis of covalently functionalized MWCNTs by diazonium chemistry and oxidation methodologies, with typically different mechanisms and reaction sites. A multi-peak deconvolution system and spectral band assignment were proposed based on the chemical and structural modifications identified by X-ray photoelectron spectroscopy, thermogravimetry, X-ray diffraction, specific surface areas and the comparative analysis of the first and second order regions of the Raman spectra. Diazonium functionalization takes place mainly in the π-system of the external sidewall, while oxidation occurs on defects and leads to structure burning. This allowed us to distinguish between spectral features related to aromaticity disruptions within the sidewalls and spectral features related to changes within the inner tubes. The model was validated extending the studies to the functionalization of MWCNTs by the Bingel reaction.
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Cigarettes are part of a collection of objects found everywhere and smoked by a large part of the population. Cigarette butts can be an essential piece of evidence in identifying a certain suspect/witness, as they can suggest the positive identification or exclusion of one or more brands by comparison or even DNA analysis. The main objective of this study is to test the capability of Handheld X-ray fluorescence spectrometer (HHXRF) to analyze the elemental concentration of individual cigarette ash of several tobacco brands and investigate if it is further possible to discriminate the different brands based on their ash's elemental concentration. This study reveals the capability of HHXRF to discriminate tobacco brands based on their ashes' elemental concentration, with the great advantage of the analyses being non-destructive and can be carried out on a small sample. In addition, this equipment can measure the ash's elemental concentrations on-site, allowing for less contamination and sample loss.
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Espectrometria por Raios X , Produtos do Tabaco , Humanos , Produtos do Tabaco/análise , Ciências Forenses/métodos , Nicotiana/químicaRESUMO
Eisenmenger syndrome (ES) is a complex, multisystemic, and rare clinical entity, given that currently, most congenital heart diseases can be corrected in childhood. The high anesthetic risk in these patients poses a challenge for anesthesiology. There are few cases described in the literature of anesthetic approaches using ketamine and dexmedetomidine in ES cases, particularly under Monitored Anesthesia Care (MAC). We describe the clinical case of a 40-year-old patient with trisomy 21, intellectual disability, and ES secondary to a single atrioventricular (AV) valve, scheduled for cranial magnetic resonance imaging (MRI) under sedation due to a suspected space-occupying lesion. Sedation was performed under MAC with dexmedetomidine and ketamine. The procedure proceeded without complications. The anesthetic approach in ES patients, given the clinical complexity, requires planning by a multidisciplinary team and should be tailored to the procedure and its duration.
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The increasing use of photoselective nets (PNs) raises the question of their influence on pollen traits. We aimed to evaluate the effect of PNs (yellow, pearl, and grey) on the pollen of 'Matua' and 'Tomuri' Actinidia deliciosa cultivars. The pollen size and the exine were studied with a light microscopy and a scanning electron microscopy, and the fertility was analysed by a viability assay and in vitro germination. The total soluble proteins (TSPs) and sugars (TSSs) were quantified by colorimetric assays. The molecular structure of the pollen grain's wall was analysed by a Raman spectroscopy. The pollen from the plants under the PNs had a larger width and area and a lower germination rate. No significant changes were observed in the exine's microperforations. The TSP and TSS contents were influenced by the cultivar and PNs (particularly the pearl PN). The Raman spectra of the pollen from the plants grown under the nets presented some bands that significantly shifted from their original position, indicating differences in the vibration modes of the molecules, but no overall changes at their structural or organisation level were found. Our study showed that the PNs could influence several pollen traits, with the pearl PN inducing greater modifications. Our results also support the idea that cultivars affect the outcome of some characteristics.
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The expansion of the Internet of Things market and the proliferation of wearable technologies have generated a significant demand for textile-based energy storage systems. This work reports the engineered design of hybrid electrode nanomaterials of N-doped carbon nanotubes (CNT-N) functionalized with two types of manganese oxides (MOs)-birnessite (MnO2) and hausmannite (Mn3O4)-and their application in solid-state textile-based hybrid supercapacitors (SCs). A versatile citric acid-mediated eco-friendly one-pot aqueous precipitation process is proposed for the fabrication of the hybrids. Remarkably, different types of MOs were obtained by simply changing the reaction temperature from room temperature to 100 °C, without any post-thermal treatment. Asymmetric textile SCs were developed using cotton fabrics coated with CNT-N and the hybrids as textile electrodes, and poly(vinyl) alcohol/orthophosphoric acid as the solid-gel electrolyte. The asymmetric devices presented enhanced energy storage performance relative to the symmetric device based on CNT-N and excellent cycling stability (>96%) after 8000 charge/discharge cycles owing to synergistic effects between CNT-N and the MOs, which endowed nonfaradaic and pseudocapacitive features to the SCs. The asymmetric SC based on CNT-N@MnO2 featured 47% higher energy density and comparable power density to the symmetric CNT-N-based device (8.70 W h cm-2 at 309.01 µW cm-2 vs. 5.93 W h cm-2 at 346.58 µW cm-2). The engineered hybrid CNT-N@MO nanomaterials and the eco-friendly citric acid-assisted one-pot precipitation route open promising prospects not only for energy storage, but also for (photo)(electro)catalysis, wastewater treatment, and (bio)sensing.
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INTRODUCTION: The dissemination of the COVID-19 pandemic in Europe, namely in Portugal, demanded an organizational and clinical reaction from the Portuguese National Health Service. With the unpredictable impact of COVID-19 infected patients redefining hospital logistics, reducing non-priority elective care and extending the hospital capacity for critical care patients made mobilizing a significant part of human resources a priority. We conducted a national survey to monitor the contribution and the role of anaesthesiologists belonging to the 53 Portuguese National Health Service hospitals in the first wave fight against the pandemic. MATERIAL AND METHODS: This prospective cross-sectional observational study used a weekly survey sent to the Directors of the Anaesthesiology Departments of all Portuguese National Health Service hospitals, between the period of 13th April and 21st June 2020. Directors were asked about human resources, hospital logistics, anaesthetic activity and residency programs in their departments as well as contingency plans facing the impact of the pandemic growth in the PNHS. RESULTS: Contingency strategy for all Portuguese National Health Service hospitals planned for a total of 1524 level III critical care beds during the initial phases of the pandemic, an increase of 151% from the existing 607 level III critical care beds in Portugal in January 2020. This re-configuration effort of the Portuguese National Health Service was only possible due to the partial or total suspension of non-urgent elective activity that reached over 90% of these institutions in the first pandemic months (March and April) and the deployment of anaesthesiologists from their normal activities to the treatment of critical care patients. During the peak of the first pandemic wave, 209 anaesthesiology specialists and 170 trainees (22.9% of the total anaesthesiologist's staff in the Portuguese National Health Service) were deployed in critical care. There was an almost complete interruption of the residency program rotation in 70.4% of hospitals with anaesthesiology residents, between March and April 2020. CONCLUSION: During the first pandemic wave there was an effective and fast reorganisation of the Portuguese National Health Service in order to increase level III critical care beds, which might have contributed to the low mortality rates in Portugal. We believe that this could have also been a result of the contribution given by all public anaesthesiology departments.
Introdução: A disseminação da pandemia por COVID-19 na Europa, designadamente em Portugal, exigiu uma resposta clínica e organizativa por parte do Serviço Nacional de Saúde português. Com o imprevisível impacto da COVID-19 nos doentes infectados, foi prioritário redefinir a logística hospitalar, reduzir a prestação de cuidados electivos não prioritários, e estender a capacidade hospitalar ao tratamento do doente crítico, mobilizando uma parte significativa dos recursos humanos. Utilizou-se um inquérito nacional que permitisse monitorizar a contribuição que os anestesiologistas pertencentes aos 53 hospitais do Serviço Nacional de Saúde tiveram no combate à COVID-19 durante a primeira vaga da pandemia. Material e Métodos: Estudo observacional transversal de tipo prospectivo, baseado num inquérito semanal enviado aos directores dos Serviços de Anestesiologia de todos os hospitais do Serviço Nacional de Saúde, entre 13 de abril e 21 de junho de 2020. Foi solicitada informação relativa aos recursos humanos, logística hospitalar, atividade assistencial, programa de formação pós-graduado, assim como plano de contingência face ao crescimento da pandemia. Resultados: O plano de contingência hospitalar nos hospitais do Serviço Nacional de Saúde previu um total de 1524 camas de cuidados intensivos de nível III, o que corresponde a um crescimento de 151% das 607 camas existentes em janeiro de 2020. Esta reconfiguração dos hospitais do Serviço Nacional de Saúde só foi possível devido à suspensão parcial ou total da atividade eletiva não prioritária que afectou mais de 90% das instituições hospitalares nos primeiros meses da pandemia (março e abril), e à mobilização dos anestesiologistas das suas atividades eletivas para o tratamento do doente crítico. Nos piores momentos, esta mobilização envolveu 209 especialistas e 170 internos de especialidade (22,9% do total destes profissionais nos hospitais do Serviço Nacional de Saúde). Por outro lado, registou-se uma interrupção quase total do programa de formação pós-graduada em mais de 70,4% dos hospitais com esta idoneidade formativa, de março a abril de 2020. Conclusão: Durante a primeira vaga da pandemia houve uma rápida reorganização do Serviço Nacional de Saúde que poderá ter contribuído para a baixa taxa de mortalidade em Portugal. Os autores acreditam que para esse resultado poderá ainda ter contribuído a ajuda dada pelos serviços de Anestesiologia do Serviço Nacional de Saúde.
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Anestesiologia , COVID-19 , Humanos , COVID-19/epidemiologia , Pandemias , Portugal/epidemiologia , Medicina Estatal , Estudos Transversais , Estudos ProspectivosRESUMO
The forensic scenario, on which the round robin study was based, simulated a suspected intentional manipulation of a real estate rental agreement consisting of a total of three pages. The aims of this study were to (i) establish the amount and reliability of information extractable from a single type of evidence and to (ii) provide suggestions on the most suitable combination of compatible techniques for a multi-modal imaging approach to forgery detection. To address these aims, seventeen laboratories from sixteen countries were invited to answer the following tasks questions: (i) which printing technique was used? (ii) were the three pages printed with the same printer? (iii) were the three pages made from the same paper? (iv) were the three pages originally stapled? (v) were the headings and signatures written with the same ink? and (vi) were headings and signatures of the same age on all pages? The methods used were classified into the following categories: Optical spectroscopy, including multispectral imaging, smartphone mapping, UV-luminescence and LIBS; Infrared spectroscopy, including Raman and FTIR (micro-)spectroscopy; X-ray spectroscopy, including SEM-EDX, PIXE and XPS; Mass spectrometry, including ICPMS, SIMS, MALDI and LDIMS; Electrostatic imaging, as well as non-imaging methods, such as non-multimodal visual inspection, (micro-)spectroscopy, physical testing and thin layer chromatography. The performance of the techniques was evaluated as the proportion of discriminated sample pairs to all possible sample pairs. For the undiscriminated sample pairs, a distinction was made between undecidability and false positive claims. It was found that none of the methods used were able to solve all tasks completely and/or correctly and that certain methods were a priori judged unsuitable by the laboratories for some tasks. Correct results were generally achieved for the discrimination of printer toners, whereas incorrect results in the discrimination of inks. For the discrimination of paper, solid state analytical methods proved to be superior to mass spectrometric methods. None of the participating laboratories deemed addressing ink age feasible. It was concluded that correct forensic statements can only be achieved by the complementary application of different methods and that the classical approach of round robin studies to send standardised subsamples to the participants is not feasible for a true multimodal approach if the techniques are not available at one location.
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Medicina Legal , Tinta , Medicina Legal/métodos , Humanos , Laboratórios , Espectrometria de Massas , Reprodutibilidade dos TestesRESUMO
The Algarve is located at a very short distance from North Africa, in Southern Portugal, and as one of the most touristic regions of Portugal, it is accessible by air, land and sea. It is very susceptible to many illegal activities, such as illegal migration, drug trafficking, kidnapping, and murder, among others. Therefore, an Algarve soils database for forensic purposes is being conducted with the conjunction of geological and palynological methodologies on soils characterization, since this is of fundamental importance to assess reliable evidence on forensic investigations. In this study, the properties of soils from several proximate sites from the Algarve were investigated, namely: (i) colour determined by spectrophotometry; (ii) particle size distribution determined by laser granulometry; (iii) low-field magnetic susceptibility by a susceptibility meter; and (iv) pollen content using a light microscope. Finally, a hierarchical cluster analysis was applied to ascertain the capacity of the different soil properties for discrimination between samples. The study reveals the utility of geobotanical techniques for forensic discrimination of soils. Even though some similarities between some of the samples were found, each one presented a combination of colour, particle size distribution, magnetic susceptibility and pollen features that enable the determination of a fingerprint expected to reveal a specific site for future selection of coastal search areas in the Algarve region.
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Scarlet fever is essentially a childhood disease, although it may occur in all ages. Early diagnosis and treatment are essential in preventing the spread of infection and progression to life-threatening complications. The case presented describes the clinical difficulty in the diagnosis of scarlet fever in an adult patient with acute involvement of the airway (oedematous laryngitis) and the need for emergent orotracheal intubation and eventually tracheotomy. A high degree of suspicion related to the airway involvement is of utmost importance in an emergency room setting.
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For industrial production of cocrystals, screening phase is essential, helping to become the process faster, more effective and efficient, reducing the quantity of reactants used and associated costs. High-throughput screening (HTS) methods can analyze a wide range of compounds simultaneously. As an answer to industrial necessity of more efficient screening methods, different methods must be developed and optimized. Vibrational spectroscopic techniques are fast, non-destructive and non-invasive, do not need pre-treatment of the samples and allow obtaining qualitative and quantitative information. They are useful in cocrystal analysis, once they detect weak interaction as hydrogen bonding, the basis of cocrystal formation. Therefore, its application in the analysis of cocrystal screening methods, together with multivariate analysis, should be studied in detail. For this end, a HTS procedure of hydrochlorothiazide (HTZ) cocrystals is performed using a 96-well plate and ultrasound-assisted cocrystallization. Six coformers were tested considering ratios of HTZ:coformer of 1:1 and 1:2. The cocrystallization products were analyzed by mid infrared spectroscopy and Raman microspectroscopy. Nicotinamide and p-aminobenzoic acid formed cocrystals with HTZ. The systems with arginine showed that the coformer suffered amorphization; however, no proof of the solid state of HTZ was obtained. The results were not conclusive for the system with citric acid. Additionally, in the nicotinamide and citric acid systems, the physical mixture of the plate also reacted without the present of solvent. Overall, the use of mid infrared spectroscopy and multivariate data analysis provided important information on cocrystal formation, purity, and correct ratio assessment.
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This paper reports a complete characterisation of poultry litter ash and its potential use as a heavy metal stabiliser. We propose a novel approach, in which the ashes deriving from municipal solid waste incineration (MSWI) are combined with poultry litter ash, rather than with coal combustion flue gas desulfurisation (FGD) residues. Heavy metals stabilisation was demonstrated by comparing the elemental concentrations in the leaching solutions of the starting raw and stabilised materials: leachable Pb and Zn showed a reduced solubility. The characterisation was conducted by total reflection X-ray fluorescence (TXRF), X-ray diffraction (XRD), micro-Raman spectroscopy and scanning electron microscopy combined with energy-dispersive X-ray spectrometry (SEM-EDX). The results showed that the poultry litter ash was Ca-, P-, K- and S-rich (>29 g/kg). It contained amorphous materials (i.e. fly ash economiser (FAECO) 73% and fly ash cyclone (FACYC) 61%) and soluble phases (e.g. arkanite and sylvite; up to 13% FAECO and 28% FACYC), as well as resilient crystalline (up to 2% of FAECO and FACYC) and amorphous phases (e.g. hydroxyapatite). After two months, the Pb and Zn concentrations in the leachate solutions were below the limit set by the European regulations for waste disposal (<0.2 mg/L and 1.5 mg/L, respectively). We propose a mechanism for the heavy metals stabilisation based on the carbonation process and high amounts of P, Ca and reactive amorphous phases. In conclusion, it is demonstrated that poultry litter ash can be an effective secondary source of heavy metals, allowing their immobilisation through P- and Ca-based reactive amorphous phases.
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Metais Pesados , Eliminação de Resíduos , Animais , Carbono , Cinza de Carvão , Incineração , Material Particulado , Aves Domésticas , Resíduos SólidosRESUMO
INTRODUCTION: The objective of this study is to identify the number of anaesthesiologists working in Portugal and to monitor the national activity of this medical specialty by comparing it with a similar Census performed in 2014. MATERIAL AND METHODS: Observational cross-sectional study. Data related to the month of May 2017 was collected from Anaesthesiology departments of 53 Portuguese public institutions from a total of 86 hospitals. RESULTS: The Census registered 615 127 surgical procedures (3.4% more than in 2013), 84.1% of which on a non-emergent basis, and 49.6% day case surgery (6.1% more than in 2013). Moreover, 89 608 procedures were performed outside the operating rooms (19.0% less than in 2013), 282 944 were anaesthetic clinics (1.3% more than in 2013) and 112 183 were chronic pain evaluations (13.1% more than in 2013). In addition, 51 380 labour analgesia were performed for delivery (14.3% more than in 2013) corresponding to 70.5% of all deliveries occurring in the Obstetric department of Portuguese public hospitals in 2016 (5% more than in 2013). A total of 1280 Anaesthesiologists were identified (2.1% more than in May 2014), corresponding to a ratio of 12.4 per 100 000 inhabitants (it was 12.0 in May 2014). Together with the 262 anaesthesiologists that work exclusively in the private system, we found a total sum of 1542 anaesthesiologists indicating a ratio of 15.1 per 100 000 inhabitants (it was 13.9 in 2014). DISCUSSION: We predict that the identified deficit of 541 anaesthesiologists in the Portuguese National Health Service should be reduced by two thirds until 2023. The reduction of the shortage of anaesthesiologists will allow an increase in human resource capacity in Anaesthesiology. CONCLUSION: Even though there was a slight increase in the ratio of Anaesthesiologists per inhabitant in 2017 compared to 2014, Portugal maintains a shortage of Anaesthesiologists.
Introdução: O objectivo deste estudo é identificar o número de anestesiologistas e monitorizar a actividade da Anestesiologia em Portugal, comparando-a com idêntico Censos realizado em 2014. Material e Métodos: Estudo observacional transversal. Foram contactados, em maio de 2017, os diretores dos serviços de Anestesiologia das instituições hospitalares com actividade cirúrgica que compõem o Serviço Nacional de Saúde, num total de 53 instituições hospitalares, correspondendo a 86 hospitais. Resultados: O Censos registou um total de 615 127 intervenções cirúrgicas (mais 3,4% que em 2013), das quais 84,1% foram cirurgias programadas e destas 49,6% em regime de ambulatório (mais 6,1% que em 2013). Constatou-se ainda a realização de 89 608 procedimentos com apoio de anestesia fora do bloco operatório (menos 19,0% que em 2013), 282 944 consultas de anestesia (mais 1,3% que em 2013) e 112 183 consultas de dor crónica (mais 13,1% que em 2013). Identificaram-se 51 380 analgesias de parto (mais 14,3% que em 2013), que corresponderam a 70,5% dos partos ocorridos nos serviços de Obstetrícia dos hospitais do Serviço Nacional de Saúde (mais 5% de partos que em 2013). Foram identificados 1280 Anestesiologistas (mais 2,1% do que em maio de 2014), o que corresponde a um rácio de 12,4 por 100 000 habitantes (este valor era de 12,0 em maio de 2014). Com os 262 Anestesiologistas a trabalhar exclusivamente no sector privado, obtém-se um total nacional de 1542 Anestesiologistas, ou seja, um rácio de 15,1 por 100 000 habitantes (este valor era 13,9 em maio de 2014). Discussão: Prevê-se que o déficit de 541 Anestesiologistas identificados, possa ser reduzido em cerca de dois terços até 2023. A redução do déficit de Anestesiologistas permitirá aumentar a capacidade de resposta às crescentes solicitações dos serviços de anestesiologia Portugueses. Conclusão: Apesar de um ligeiro aumento do rácio de anestesiologistas por habitante em 2017 comparativamente a 2014, Portugal continua com um déficit de Anestesiologistas.
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Anestesiologia/estatística & dados numéricos , Mão de Obra em Saúde/estatística & dados numéricos , Censos , Estudos Transversais , Feminino , Humanos , Masculino , Portugal , Fatores de TempoRESUMO
The integration of nanomaterials in the field of (bio)sensors has allowed developing strategies with improved analytical performance. In this work, ultrasmall core-shell Fe3O4@Au magnetic nanoparticles (MNPs) were used as the platform for the immobilization of event-specific Roundup Ready (RR) soybean and taxon-specific DNA sequences. Firstly, monodisperse Fe3O4 MNPs were synthesized by thermal decomposition and subsequently coated with a gold shell through reduction of Au(III) precursor on the surface of the MNPs in the presence of an organic capping agent. This nanosupport exhibited high colloidal stability, average particle size of 10.2⯱â¯1.3â¯nm, and spherical shape. The covalent immobilization of ssDNA probe onto the Au shell of the Fe3O4@Au MNPs was achieved through a self-assembled monolayer (SAM) created from mixtures of alkane thiols (6-mercapto-1-hexanol and mercaptohexanoic acid). The influence of the thiols ratio on the electrochemical performance of the resulting electrochemical genoassays was studied, and remarkably, the best analytical performance was achieved for a pure mercaptohexanoic acid SAM. Two quantification assays were designed; one targeting an RR sequence and a second targeting a reference soybean gene, both with a sandwich format for hybridization, signaling probes labelled with fluorescein isothiocyanate (FITC), enzymatic amplification and chronoamperometric detection at screen-printed carbon electrodes (SPCE). The magnetogenoassays exhibited linear ranges from 0.1 to 10.0â¯nM and from 0.1 to 5.0â¯nM with similar detection limits of 0.02â¯nM and 0.05â¯nM for the event-specific (RR) and the taxon-specific (lectin) targets, respectively. The usefulness of the approach was demonstrated by its application to detect genetically modified organisms (GMOs) in feed and food.
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Técnicas Biossensoriais/métodos , DNA de Plantas/genética , Glycine max/genética , Ouro/química , Nanopartículas de Magnetita/química , Hibridização de Ácido Nucleico , Plantas Geneticamente Modificadas/genética , Técnicas Eletroquímicas/métodos , Nanopartículas de Magnetita/ultraestruturaRESUMO
Novel photochromic hybrid nanomaterials were prepared through the immobilization of the lacunary Keggin-type phosphomolybdate (TBA4H3[PMo11O39]·xH2O, denoted as PMo11) and sandwich-type lanthano phosphomolybdates (K11[Ln(III)(PMo11O39)2]·xH2O, denoted as Ln(PMo11)2, where Ln(III) = Sm, Eu, Gd, Tb and Dy) onto positively-charged functionalized silica nanoparticles. The functionalized silica nanoparticles were prepared by a one-step co-condensation route between tetraethyl orthosilicate and dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride, presenting an average particle size of 95 ± 26 nm, a spherical morphology and a pore diameter of 13.7 nm. All characterization techniques proved the successful immobilization of the phosphomolybdates. The photochromic properties of the resulting hybrid nanomaterials in the solid state were evaluated by UV-Vis spectroscopy and colorimetry. All materials revealed promising photochromic properties under UV irradiation (λ = 254 nm). The lacunary phosphomolybdate anchored onto the silica nanoparticles, C18-SiO2@PMo11, showed the best photoswitching properties, with the color changing from green to dark-blue (ΔE* = 26.8). Among the Ln(PMo11)2-based hybrid nanomaterials, those containing higher Mo loadings--Eu(III)- and Tb(III)-based samples--presented more significant color changes from green to dark-blue (ΔE* = 18.8-18.9). These results revealed that the optical properties of the as-prepared hybrid nanomaterials did not depend directly on the type of Ln(III) cation, but only on the amount of Mo, which was the target element responsible for the photochromic behavior.
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In a forensic investigation, the analysis of earth materials such as sediments and soils have been used as evidence at a court of law, relying on the study of properties such as color, particle size distribution and mineral identification, among others. In addition, the analysis of the organic composition of sediments and soils is of particular value, since these can be used as complementary independent evidence to the inorganic component. To investigate the usefulness of organic indicators in sediment characterization and discrimination, seventy-seven samples were collected during a period of one year in two river beaches located at the southern bank of the Douro River estuary in the North of Portugal. Isotopes of total carbon, pollen and plant wax-marker analyses were performed. In both beaches, an increase of the organic matter concentrations was noticeable, moving landward, related with the higher cover of associated plant material. The results obtained showed that the combination of all the techniques adopted showed a clear discrimination between samples from the two beaches, and also showed a differentiation of samples in relation to distance from the river in both beaches. The results also show that seasonality in these beaches was not a determining factor for discrimination, at the times considered. In addition, the effects of time was not marked.
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Rios , Solo/química , Isótopos de Carbono/análise , Análise por Conglomerados , Componentes Aéreos da Planta , Plantas , Pólen , Portugal , Análise de Componente Principal , Estações do Ano , Esporos , Ceras/análiseRESUMO
In this study, the colour of 23 sediment samples collected in different Portuguese beaches in the North (Entre-Douro and Minho) and 33 in the South (Algarve) was tested. Spectral colour parameters (L*a*b*) were measured after several presentation/pre-treatment methods: drying at 40 degrees C, sieving (<150 and <63 microm) and ashing at 850 degrees C, using a Konica Minolta CM-2600d spectrophotometer. A descriptive statistical analysis with L*a*b* values for each presentation/pre-treatment method was performed to ascertain within-sample reproducibility followed by a hierarchical cluster analysis to obtain significant discrimination between samples using colour analysis. The samples analysed presented a colour closest to red and yellow continuums and a lightness close to the pale side of the L*a*b* system colour sphere with samples collected in the North presenting analysis on average darker L values than the samples collected in the South. The cluster analysis, dried, unsieved bulk samples L*a*b* values gave the best discrimination between samples. The clusters analysis dried, unsieved bulk samples-dried, sieved <150 microm fraction set allowed better discrimination between samples compared with the dried, sieved <63 microm fraction set or dried, unsieved bulk samples-ashed bulk, unsieved samples set and even with dried, unsieved bulk samples/dried, sieved <150 microm fraction/dried, sieved <63 microm fraction/ashed bulk, unsieved samples considered all together.
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OBJECTIVE: To validate a Spanish-language questionnaire to be used in primary care consultations to detect cases of violence against women. METHODS: The validation study was carried out between October 2002 and October 2003 in the Program of General Internal Medicine of the Clinical Hospital of the University of Buenos Aires, in the city of Buenos Aires, Argentina. The original version of this Spanish-language questionnaire had been developed in sexual and reproductive health clinics of five countries of Latin America and the Caribbean. The questionnaire covered the most frequent forms of gender-based violence (emotional, physical, sexual, and sexual abuse during childhood); explored how and when the violence occurred and who perpetrated it; and investigated the patient's perception of her current risk. In the research in Buenos Aires the format and theoretical content of the survey were evaluated, and linguistic and psychometric validations were also carried out. The reliability of the tool was assessed in terms of its reproducibility, stability, and internal consistency. RESULTS: The study found that the women surveyed in Buenos Aires had a good understanding of the questions, the examples given with the questions, and the response options. The women did not perceive the survey as being intimidating or as an intrusion into their private lives. The women generally regarded the use of the survey in primary care settings as a key opportunity for them to express their suffering and to receive assistance. The level of agreement for the answers to the questions in all five areas (psychological violence, physical violence, sexual violence, sexual abuse during childhood, and perception of current risk) was very high, in terms of both reproducibility (kappa values of 0.63 to 1.00) and stability (kappa values of 0.62 to 1.00). The alpha correlation coefficient for internal consistency was 0.755 for psychological violence and physical violence, 0.498 for psychological violence and sexual violence, 0.596 for physical violence and sexual violence, and 0.715 for the different manifestations of violence (psychological, physical, sexual, and abuse during childhood). CONCLUSION: This research demonstrated the soundness of the brief questionnaire, in terms of its format, content, comprehensiveness, and reliability. This instrument can be used in clinical consultations to detect situations of psychological violence, physical violence, sexual violence, and sexual abuse during childhood.