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Luigi Antonello Armando’s reflections on Machiavelli present elements of novelty and originality. Regarding Machiavelli’s most famous work, The Prince, Armando argues that it has been read in a way that overlooks the significance of the expression “al tutto nuovo” (“completely new”), referring to a prince “without a father,” who, through fortune (opportunity), was given only the unimpeded possibility to shape events, thus becoming the creator, through his own virtue, of the beginning “of a possible history”. The Author passionately focuses on the “mind” of such a prince, who can be “wise” and present himself as a model rather than imitating misleading models. In these pages, an attempt is made to compare the Author’s interpretative proposal with Machiavelli’s dramatic conception of man and history.

O estudo apresentado neste artigo está inserido no campo investigativo da Análise Sintática do Espaço, em particular quanto ao emprego de simulação de mudanças na configuração urbana por meio da investigação de possíveis impactos socioespaciais da construção de uma nova ponte em Natal. O problema de pesquisa centra-se em identificar ganhos e perdas de acessibilidade após realizadas as intervenções e em questionar quem seria o público mais favorecido com tais mudanças. Para tanto, foram modeladas representações (mapas de segmentos) da malha viária da área urbana contínua de Natal, simulando-se um cenário transformado pela introdução da ponte. Valores de acessibilidade origem-destino (NAIN) e de atravessamento (NACH), referentes às situações de antes e depois, foram comparados a dados censitários relativos a padrões de distribuição de renda em Natal. Os resultados apontam para a redistribuição de vetores de alta integração da periferia para o centro geométrico (bairro Potengi) da Região Administrativa Norte de Natal, e para o aumento da acessibilidade em áreas antigas de ocupação (Cidade Alta e Alecrim), potencialmente estendendo-se ao sítio definido como o centro histórico de Natal (Cidade Alta/Ribeira). O atual centro topológico da cidade, na região Leste/Sul, mais rica economicamente, é fortalecido. Como exposto em estudos anteriores, alguns referidos neste artigo, os efeitos de ganho de acessibilidade em centros antigos têm suscitado transformações às vezes radicais do cenário construído, raramente condizentes com a noção de preservação de bens culturais.

Abstract Background Multiple acyl-CoA dehydrogenase deficiency (MADD) or glutaric aciduria type II is an extremely rare autosomal recessive inborn error of fatty acid beta oxidation and branched-chain amino acids, secondary to mutations in the genes encoding the electron transfer flavoproteins A and B (ETFs; ETFA or ETFB) or ETF dehydrogenase (ETFDH). The clinical manifestation of MADD are heterogeneous, from severe neonatal forms to mild late-onset forms. Case presentation We report the case of a preterm newborn who died a few days after birth for a severe picture of untreatable metabolic acidosis. The diagnosis of neonatal onset MADD was suggested on the basis of clinical features displaying congenital abnormalities and confirmed by the results of expanded newborn screening, which arrived the day the newborn died. Molecular genetic test revealed a homozygous indel variant c.606 + 1 _606 + 2insT in the ETFDH gene, localized in a canonical splite site. This variant, segregated from the two heterozygous parents, is not present in the general population frequency database and has never been reported in the literature. Discussion and conclusion Recently introduced Expanded Newborn Screening is very important for a timely diagnosis of Inherited Metabolic Disorders like MADD. In some cases which are the most severe, diagnosis may arrive after symptoms are already present or may be the neonate already died. This stress the importance of collecting all possible samples to give parents a proper diagnosis and a genetic counselling for future pregnacies.

The molecular approach of DNA barcoding for the characterization and traceability of food products has come into common use in many European countries. However, it is important to address and solve technical and scientific issues such as the efficiency of the barcode sequences and DNA extraction methods to be able to analyze all the products that the food sector offers. The goal of this study is to collect the most defrauded and common food products and identify better workflows for species identification. A total of 212 specimens were collected in collaboration with 38 companies belonging to 5 different fields: seafood, botanicals, agrifood, spices, and probiotics. For all the typologies of specimens, the most suitable workflow was defined, and three species-specific primer pairs for fish were also designed. Results showed that 21.2% of the analyzed products were defrauded. A total of 88.2% of specimens were correctly identified by DNA barcoding analysis. Botanicals (28.8%) have the highest number of non-conformances, followed by spices (28.5%), agrifood (23.5%), seafood (11.4%), and probiotics (7.7%). DNA barcoding and mini-barcoding are confirmed as fast and reliable methods for ensuring quality and safety in the food field.

Hepatic-related diseases, in particular hyperlipidemia and hypercholesterolemia, are a thorn on the side of the national health institutes around the globe. Indeed, liver lipid and cholesterol dysregulation could lead to atherosclerotic plaque formation and cardiovascular diseases. Currently, statin administration and monacolin K consumption are the main therapies proposed to counter this alarming connection, but relevant side effects are known. To overcome this issue, safe nutraceutical formulations and/or vegetal extracts, endowed with anticholesterolemic activity, could be instrumental in hypercholesterolemia prevention and treatment. In the present work, the anticholesterolemic efficacy of three vegetal extracts used in traditional medicine (artichoke, caigua, and fenugreek), their unique blend (ACFB), and the monacolin K-containing red yeast extract (RYR), was investigated with an in vitro approach based on hepatic cell line HepG2. The impact on cholesterol of the three extracts, their blend, and RYR were investigated by determining hepatocyte total and free cholesterol and bile acids biosynthesis. According to our results, the anticholesterolemic activity of the vegetal extracts was confirmed, and a novel choleretic activity of caigua extract was evidenced. ACFB showed to be safer than RYR while showing a similar effect on total and free cholesterol and bile acids synthesis compared to it. The anticholesterolemic activity of the blend was obtained with lower vegetal extract concentrations compared with the single vegetal extract, potentially indicating an additive effect between the extracts. In conclusion, the vegetal extracts and their blend, ACFB, are safe and are endowed with anticholesterolemic activity, potentially providing complementary therapies to the statin-based ones for hyperlipidemia and hypercholesterolemia-related complications.

In this contribution, new data concerning the distribution of vascular flora alien to Italy are presented. It includes new records, confirmations, exclusions, and status changes for Italy or for Italian administrative regions of taxa in the genera Bunias, Calocedrus, Calycanthus, Celosia, Clerodendrum, Convolvulus, Crassula, Cyclamen, Datura, Dicliptera, Eragrostis, Erigeron, Gamochaeta, Gazania, Impatiens, Kolkwitzia, Leucaena, Ludwigia, Medicago, Muscari, Nigella, Oenothera, Opuntia, Paulownia, Petroselinum, Phyllostachys, Physalis, Pseudosasa, Quercus, Reynoutria, Roldana, Saccharum, Sedum, Semiarundinaria, Senecio, Sisyrinchium, Solanum, Sporobolus, Tulipa, Vachellia, Verbena, and Youngia. Nomenclatural and distribution updates published elsewhere are provided as Suppl. material 1.

Medicinal plants have been widely used in traditional medicine due to their therapeutic properties. Although they are mostly used as herbal infusion and tincture, employment as ingredients of food supplements is increasing. However, fraud and adulteration are widespread issues. In our study, we aimed at evaluating DNA metabarcoding as a tool to identify product composition. In order to accomplish this, we analyzed fifteen commercial products with DNA metabarcoding, using two barcode regions: psbA-trnH and ITS2. Results showed that on average, 70% (44–100) of the declared ingredients have been identified. The ITS2 marker appears to identify more species (n = 60) than psbA-trnH (n = 35), with an ingredients’ identification rate of 52% versus 45%, respectively. Some species are identified only by one marker rather than the other. Additionally, in order to evaluate the quantitative ability of high-throughput sequencing (HTS) to compare the plant component to the corresponding assigned sequences, in the laboratory, we created six mock mixtures of plants starting both from biomass and gDNA. Our analysis also supports the application of DNA metabarcoding for a relative quantitative analysis. These results move towards the application of HTS analysis for studying the composition of herbal teas for medicinal plants’ traceability and quality control.

O presente trabalho tem como objetivo principal analisar a configuração da favela a partir de seus padrões socioespaciais, buscando entender o fenômeno em sua escala global. Adota-se para o estudo a Sintaxe Espacial enquanto abordagem teórica, metodológica e ferramental, permitindo a leitura do objeto em sua complexidade espacial. São comparados 120 assentamentos localizados ao redor do mundo, explorados segundo um conjunto de 26 variáveis configuracionais (entre qualitativas e quantitativas, geométricas e topológicas). Os resultados são, também, balizados por amostra de 45 cidades portuguesas de origem medieval (exemplares da cidade orgânica) e pela pesquisa de Medeiros (2013) para 44 cidades brasileiras (ilustrativas de estruturas urbanas contemporâneas). Busca-se a existência de um padrão espacial na favela e entender em que medida a favela reproduz padrões espaciais inerentes à cidade orgânica e historicamente consolidados. A pesquisa sustenta-se na hipótese de que a configuração da favela revela padrões espaciais provenientes das suas práticas de auto-organização, que são responsáveis por dinâmicas urbanas de sucesso. Os achados revelam que a favela se organiza dentro do sistema maior que a recebe, partilhando lógicas comuns e transversais a várias regiões do mundo e contextos culturais. Reconhecem-se, ainda, padrões comuns aos que estruturam cidades orgânicas revelando processos semelhantes de desenvolvimento.

In this case report, we characterize a novel inherited frameshift mutation c.4700_4701del (p.Phe1567Cysfs*221) in a single copy of the SCN5A gene and its association with Brugada syndrome (BrS). The proband experienced a life-threatening ventricular arrhythmia successfully treated with DC-shock and he also suffered from supraventricular tachycardia. Ajmaline test confirmed the BrS diagnosis. No other mutation nor low frequency variants in the other 23 analyzed genes were detected. The same mutation was found in the father and sister, who were both diagnosed with BrS. We hypothesize that this mutation could be responsible for BrS and potentially linked to supraventricular tachycardias. Further studies are needed to confirm this observation and to assess the clinical relevance of this mutation, in terms of risk-stratification.

In this case series, we report for the first time a family in which the inherited nonsense mutation [c. 3946C > T (p.Arg1316*)] in the SCN5A gene segregates in association with Brugada syndrome (BrS). Moreover, we also report, for the first time, the frameshift mutation [c.7686delG (p.Ile2563fsX40)] in the NF1 gene, as well as its association with type 1 neurofibromatosis (NF1), characterized by pigmentary lesions (café au lait spots, Lisch nodules, freckling) and cutaneous neurofibromas. Both of these mutations and associated phenotypes were discovered in the same family. This genetic association may identify a subset of patients at higher risk of sudden cardiac death who require the appropriate electrophysiological evaluation. This case series highlights the importance of genetic testing not only to molecularly confirm the pathology but also to identify asymptomatic family members who need clinical examinations and preventive interventions, as well as to advise about the possibility of avoiding recurrence risk with medically assisted reproduction.

The global market of food supplements is growing, along with consumers demand for high-quality herbal products. Nevertheless, substitution fraud, and adulteration cases remain a common safety problem of global concern. In the last years, the DNA barcoding approach has been proposed as a valid identification method and it is now commonly used in the authentication of herbal and food products. The objective of this study was to evaluate whether DNA barcoding can be applied to trace the plant species from the starting raw material to the finished commercial products. We selected a panel of 28 phytoextracts obtained through three different extraction methods (i.e., maceration, percolation and sonication) with different solvents (i.e., ethanol, deionized water and glycerol). Furthermore, we chose six plant species for which we collected and analysed all the intermediates of the industrial production. We sequenced and analyzed the sequence variability at DNA barcoding (psbA-trnH, ITS) and minibarcoding (rbcL 1-B) marker regions. Phytoextracts obtained through hydroalcoholic treatment, with the lower percentage of ethanol (

Recent studies have highlighted the role of the grapevine microbiome in addressing a wide panel of features, ranging from the signature of field origin to wine quality. Although the influence of cultivar and vineyard environmental conditions in shaping the grape microbiome have already been ascertained, several aspects related to this topic, deserve to be further investigated. In this study, we selected three international diffused grapevine cultivars (Cabernet Sauvignon, Syrah, and Sauvignon Blanc) at three germplasm collections characterized by different climatic conditions [Northern Italy (NI), Italian Alps (AI), and Northern Spain (NS)]. The soil and grape microbiome was characterized by 16s rRNA High Throughput Sequencing (HTS), and the obtained results showed that all grape samples shared some bacterial taxa, regardless of sampling locality (e.g., Bacillus, Methylobacterium, Sphingomonas, and other genera belonging to Alphaproteobacteria, Gammaproteobacteria, and Actinobacteria). However, some Operational Taxonomic Units (OTUs) could act as geographical signatures and in some cases as cultivar fingerprint. Concerning the origin of the grape microbiome, our study confirms that vineyard soil represents a primary reservoir for grape associated bacteria with almost 60% of genera shared between the soil and grape. At each locality, grapevine cultivars shared a core of bacterial genera belonging to the vineyard soil, as well as from other local biodiversity elements such as arthropods inhabiting or foraging in the vineyard. Finally, a machine learning analysis showed that it was possible to predict the geographical origin and cultivar of grape starting from its microbiome composition with a high accuracy (9 cases out of 12 tested samples). Overall, these findings open new perspectives for the development of more comprehensive and integrated research activities to test which environmental variables have an effective role in shaping the microbiome composition and dynamics of cultivated species over time and space.

This paper presents BEval, an extension of Atelier B to improve automation in the verification activities in the B method or Event-B. It combines a tool for managing and verifying software projects (Atelier B) and a model checker/animator (ProB) so that the verification conditions generated in the former are evaluated with the latter. In our experiments, the two main verification strategies (manual and automatic) showed significant improvement as ProB's evaluator proves complementary to Atelier B built-in provers. We conducted experiments with the B model of a micro-controller instruction set; several verification conditions, that we were not able to discharge automatically or manually with AtelierB's provers, were automatically verified using BEval.

Grape berries harbor a wide range of microbes originating from the vineyard environment, many of which are recognized for their role in the must fermentation process shaping wine quality. To better clarify the contribution of the microbiome of grape fruits during wine fermentation, we used high-throughput sequencing to identify bacterial and fungi communities associated with berries and musts of Cannonau. This is the most important cultivar-wine of Sardinia (Italy) where most vineyards are cultivated without phytochemical treatments. Results suggested that microbiomes of berries collected at four different localities share a core composition characterized by Enterobacteriales, Pseudomonadales, Bacillales, and Rhodospirillales. However, any area seems to enrich berries microbiome with peculiar microbial traits. For example, berries belonging to the biodynamic vineyards of Mamoiada were rich in Bacillales typical of manure (i.e. Lysinibacillus, Bacillus, and Sporosarcina), whereas in the Santadi locality, berries showed soil bacteria such as Pasteurellales and Bacteroidales as well as Rhodospirillales and Lactobacillales which are commonly involved in wine fermentation. In the case of fungi, the most abundant taxa were Dothioraceae, Pleosporaceae, and Saccharomycodaceae, and although the proportion of these families varied among localities, they occurred ubiquitously in all vineyards. During vinification processes performed at the same wine cellar under controlled conditions and without using any yeast starter, more than 50% of bacteria groups of berries reached musts, and each locality had its own private bacteria signature, even if Saccharomyces cerevisiae represented the most abundant fungal species. This work suggests that natural berries microbiome could be influenced by pedoclimatic and anthropologic conditions (e.g., farming management), and the fruits' microorganisms persist during the fermentation process. For these reasons, a reliable wine genotyping should include the entire holobiont (plant and all its symbionts), and bioprospecting activities on grape microbiota could lead to improved viticulture yields and wine quality.

Com o propósito de minimizar os custos com a alimentação, tem-se buscado a utilização dos resíduos viáveis à nutrição animal. "Batata diversa" é o nome atribuído ao tubérculo impróprio para o consumo humano, pois não alcança padrões de comercialização tanto em tamanho quanto em qualidade. A determinação das frações degradáveis ou não no rúmen é de fundamental importância no balanceamento de rações para bovinos. Sendo assim, a técnica de degradabilidade in situ tem sido utilizada para determinar o desaparecimento de nutrientes no rúmen em função do tempo. Dessa forma, objetivou-se produzir e estimar a degradabilidade in situ das diferentes frações da silagem de capim-napier produzida com diferentes níveis do farelo de "batata diversa". O experimento foi conduzido no Departamento de Zootecnia da Universidade Federal de Lavras. Para a ensilagem, foram utilizados silos experimentais de PVC, adaptados com válvula tipo Bünsen, com capacidade para aproximadamente 3 kg cada. Os tratamentos constituíram-se dos níveis 0%, 5%, 10%, 15% e 20% de inclusão do farelo de "batata diversa" ao capim-napier. O delineamento experimental utilizado foi o inteiramente casualizado, com cinco tratamentos e quatro repetições. Este estudo mostrou que a adição de 15% e 20% do farelo de "batata diversa" ao ensilar o capim-napier proporcionou melhores resultados que caracterizam uma boa silagem e maiores valores de degradabilidade ruminal in situ da MS, PB e FDN.With the purpose of minimizing the costs of feeding, the use of residues viable to animal nutrition has been searched. "Discarded potato" is the name ascribed to the tuber improper for human consumption, because it does not reach commercialization standards lather in size and quality. The determination of the degradable or not fractions in the rumen is of fundamental importance in the balancing of diets for bovines. So, the in situ degradability technique has been employed to determine the disappearance of nutrients in the rumen as related to the time. Thus, it was aimed to produce and estimate the in situ degradability of the different fractions of elephant grass silage produced with different levels of "discarded potato" meal added to the silage. The experiment was carried out in the Animal Science Department of the Federal University of Lavras. For ensiling, experimental PVC silos fitted with a Bunsen-type valve with a capacity of about 3 kg each were utilized. The treatments consisted of the levels of 0%, 5%, 10%, 15% and 20% of inclusion of "discarded potato" meal into elephant grass. The experimental utilized was the completely randomized design with five treatments and four replicates. This study showed that addition of 15% and 20% of "discarded potato" to elephant grass silage provided better results which characterize a good silage and higher values of in situ ruminal degradability for DM, CP and NDF.

This outlook paper addresses the problem of the traceability of minor crops. These kinds of cultivations consist in a large number of plants locally distributed with a modest production in terms of cultivated acreage and quantity of final product. Because of globalization, the diffusion of minor crops is increasing due to their benefit for human health or their use as food supplements. Such a phenomenon implies a major risk for species substitution or uncontrolled admixture of manufactured plant products with severe consequences for the health of consumers. The need for a reliable identification system is therefore essential to evaluate the quality and provenance of minor agricultural products. DNA-based techniques can help in achieving this mission. In particular, the DNA barcoding approach has gained a role of primary importance thanks to its universality and versatility. Here, we present the advantages in the use of DNA barcoding for the characterization and traceability of minor crops based on our previous or ongoing studies at the ZooPlantLab (Milan, Italy). We also discuss how DNA barcoding may potentially be transferred from the laboratory to the food supply chain, from field to table.

Objectives. To evaluate the recurrence of congenital heart disease (CHD) in pregnant women with familial risk who had been referred for fetal echocardiography. Material and Methods. 1634 pregnancies from 1483 women with familial history of CHD in one or more relatives were studied. Fetal cardiologic diagnosis was compared with postnatal findings at 6 months or at autopsy. Results. Total recurrence rate of CHD was 3.98%, 4.06% in single familial risk, 2.9% in double, and 5% in multiple risk. It was 3.5% in case of one previously affected child; 4.5% with 2 children; 5.2% with the mother alone affected and 7,5% with father alone affected and 3.5% with a single distant relative. Exact concordance of CHD was found in 21.5% and a partial concordance in 20% of cases. Conclusions. Our data show a higher recurrence rate of CHD than previously published data and high relative risk ratios compared to normal population.

Recent studies have demonstrated the association between constitutional ring chromosome 21 (r(21)c) and the development of B-cell acute lymphoblastic leukemia (B-ALL) with intrachromosomal amplification of chromosome 21 (iAMP21). iAMP21 acts as a driver which is often accompanied by secondary alterations that influence disease progression. Here, we report an atypical case of iAMP21 B-ALL with a unique molecular profile in the context of r(21)c. The onset of B-ALL occurred significantly earlier than previously reported in iAMP21-ALL, likely due to the presence of r(21)c. Only scarce cases of iAMP21 with concomitant PAX5 fusions have been reported. Through an extensive genomic characterization, the novel WWOX::PAX5 as well as 13q12.2 deletion involving FLT3 overexpression was found. These findings suggest that r(21)c may induce chromosomal instability on chromosome 21, triggering chromothripsis and leading to iAMP21-ALL. This case provides valuable insights to unravel the complex interplay between germline and somatic genetic alterations in leukemia. Moreover, it underscores the need for thorough genetic evaluation and multidisciplinary management in patients with syndromic presentation, particularly when rare genetic events may contribute to hematologic malignancies.

Inorganic hybrid materials have promising applications in absorbers and for the photon harvesting of solar irradiation, such as in DSSC photoanodes. Moreover, investigation of the interactions between the photoanode constituent materials is extremely important, since it is known that the properties of the materials are strongly dependent on the nucleation and growth process. Therefore, the purpose of this work was to synthesize a system consisting of a synergic combination of two inorganic hosts, BaTiO 3 and CaF 2 , synthesized together through a microwave-assisted hydrothermal method, which allows single-phase materials to be obtained after short synthesis times and at low temperatures. The increase in optical activity was investigated after the insertion of Eu ions. From the structural results, it was possible to observe that the method used to obtain the system was efficient, even using temperatures as low as 140 °C and a reaction time of one minute. The optical properties (emission and excitation) were evaluated in the visible and VUV region from 2.5 to 10.5 eV. The XANES Eu L iii edge differences associated with the XEOL results indicate that the synthesis method incorporated Eu 3+ in the hosts and the surface of the two compounds, BaTiO 3 and CaF 2 . Therefore, the combination between the Eu 3+ activators and the F centers of the host increased the range for photon harvesting, making these systems a promising material for future applications in photoanodes for DSSCs.

This paper reports a luminescence mechanism in Eu-doped BaAl2O4 excited with monochromatic X-rays (also known as X-ray excited optical luminescence - XEOL) from synchrotron radiation. The material was prepared via a proteic sol-gel methodology. The X-ray absorption near edge structures (XANES) at the Ba LIII- and Eu LIII-edges exhibit typical absorption spectra. XEOL spectra recorded in energy ranges, either around the Ba LIII- or Eu LIII-edges, showed important differences concerning the intensity of the Eu(2+) or Eu(3+) emission bands. Nevertheless, the total area under the XEOL spectra increases as the energy of the X-ray photons increases in both ranges (Ba LIII- and Eu LIII-edges).

Xerogels of strontium chlorate and aluminium chlorate doped with europium (un-co-doped) and co-doped with rare earth ions (Ln = Gd, Dy, Er and Y) were prepared using the proteic sol-gel route. Synchrotron radiation was used to investigate the effect of different co-dopants on the Eu(3+) → Eu(2+) reduction process during the synthesis of the samples. Samples were excited at the Eu LIII-edge and the XANES regions were analyzed. The results suggest that some of the Eu ions can be stabilized in the divalent state and that it is difficult to completely reduce Eu(3+) to Eu(2+) during thermal treatment. The mechanisms of the Eu reduction processes are explained by a proposed model based on the incorporation of charge-compensation defects.

X-ray-excited optical luminescence (XEOL) emission and excitation spectra as well as the EXAFS signal of CdWO(4) were measured in the energy region of the Cd and W absorption edges. From EXAFS refinement, structural parameters such as number of atoms, distance from the absorbing atom and width of coordination shells in the W neighborhood were determined. The role of W-O interactions on the intrinsic luminescence of CdWO(4) is discussed. The efficiencies of conversion, transfer and emission processes involved in the scintillation mechanism showed to be high when self-trapped excitons are formed locally by direct excitation of W ions. Annihilation of these excitons provides the characteristic scintillation of CdWO(4), a broad band emission with maximum at 500 nm. The presence of two energetically different O positions in the lattice gives rise to the composite structure of the luminescence band, and no influence of extrinsic defects was noticed. A mismatch between the X-ray absorption coefficient and the zero-order luminescence curves corroborates that the direct excitation of Cd ions induces secondary electronic excitations not very effective in transferring energy to the luminescent group, WO(6).

This paper describes computer modelling of thorium doping in crystalline LiCaAlF(6) and LiSrAlF(6). The study has been motivated by the interest in using these materials as hosts for (229)Th nuclei, which are being investigated for use as frequency standards. The dopant sites and form of charge compensation are obtained; this information is essential for the further development and optimization of these devices.

In this work the different concentrations of soluble elements in soils from natural (peridotitic soils) and anthropogenic (soils affected by a pyrite-mine spill) origin, are used to determine the phytotoxicity in lettuce (Lactuca sativa L.). The solutions are obtained from soil:water extracts (1:1), having neutral pH and high concentrations of As, Pb, Zn, Mn, Co and Ni, with values exceeding the toxic level for soil solution [Bohn HL, McNeal BL, O'Connor GA. Soil Chemistry, Wiley Interscience. Wiley & Sons, New York, 1985]. The variables evaluated are: Seed Germination (SG), Root Elongation (RE), Germination Rate (GR) and Root Necrosis (RN). The most sensitive variables in the bioassay with these solutions are GR and RN, in these cases the solution causes a reduction of 44% and 67%, respectively, in relation to control (distilled water). The test using soil-water solutions is sensitive and reproducible to determine phytotoxicity in lettuce caused by potentially pollutant elements in soils.

In the present work, electron paramagnetic resonance (EPR) spectra and thermoluminescence (TL) emission of colourless natural topaz from Santo Antônio do Jacinto, Brazil, was studied as a function of thermal treatment and gamma irradiation dose, focussing on the use of this material as a radiation dosimeter. EPR measurements on "as-received" samples at room temperature provided signals in the region of about 500 at 5,000 G. The signal located around g approximately equal to 2, frequently attributed to (AlO(4))(0), increased with additional gamma dose and disappeared after thermal treatment at 500 degrees C for 1h. Irradiation after thermal treatment recovered this signal. The decay promoted by isochronal thermal treatment showed the (AlO(4))(0) defects to be directly related to the TL glows peaks. The variation of EPR spectrum with annealing temperature prior to irradiation showed that the variation of TL sensitivity is a consequence of the variation of the (AlO(4))(0) population.

Dose measurements are acknowledged to be a vital part of the quality assurance process in diagnostic radiology, and the use of thermoluminescence dosemeters (TLDs) is a recommended method of entrance dose evaluation. Measurement of doses in radiographic examinations is widely adopted in clinical practice for adults as well as for children. Phantoms can be used to simulate different parts of the body, depending on the materials used to build them. In this work two different sets of phantoms have been prepared with acrylic blocks. The first set was used to simulate children of different ages. The second set was used to simulate the adult spine. The dosimetric measurements have been carried out using TLD and an ionising chamber. Measurements were performed in three X-ray equipments in Aracaju, Brazil. The entrance, half thickness and exit surface doses were analysed.

Optically stimulated luminescence (OSL) has become the technique of choice in many areas of dosimetry. Natural materials like topaz are available in large quantities in Brazil and other countries. They have been studied to investigate the possibility of use its thermoluminescence (TL) properties for dosimetric applications. In this work, we investigate the possibility of utilising the OSL properties of natural Brazilian topaz in dosimetry. Bulk topaz samples were exposed to doses up to 100 Gy of beta radiation and the integrated OSL as a function of the dose showed linear behaviour. The fading occurs in the first 20 min after irradiation but it is <6% of the integrated OSL measured shortly after exposure. We conclude that natural colourless topaz is a very suitable phosphor for OSL dosimetry.

This paper describes a new computational method for predicting the optical behaviour of doped inorganic materials. There is considerable interest in using inorganic materials in photonic devices, and in many cases, the optical properties of these materials depend on doping by ions such as those from the rare earth series. Among the inorganic materials of interest are the mixed metal fluorides (e.g. BaLiF(3), BaY(2)F(8), YLiF(4), LiCaAlF(6), LiSrAlF(6)), doped with trivalent rare earth ions. The paper describes the use of Mott-Littleton calculations to determine the optimum location for dopant ions, followed by crystal field calculations which make direct use of the output of the Mott-Littleton calculations to calculate the optical properties of the dopant ion taking into account its symmetry and the positions of the surrounding ions, including any vacancies or interstitial ions present by virtue of charge compensation. It is then possible to predict whether a given dopant ion at a particular site in a material will have favourable optical properties.

The thermoluminescent properties of composites containing powdered topaz embedded in Teflon or glass were studied and compared with the corresponding properties of the well known TLD-100 commercial dosimeters. Relative sensitivity, TL fading, reproducibility of the sample preparation process, and possibility of re-utilisation of the dosimeters were investigated. Measurements of absorbed doses in simulated radiotherapy treatments were also taken. The irradiations were performed using gamma rays from a 60Co source in the dose range from 1cGy to 2Gy. The dosimeters were installed in badges and attached inside acrylic plates of various thicknesses in the radiation fields. The dose profiles obtained with this procedure are very similar to the ones obtained with equivalent tissues. It is concluded that these composites of natural colourless topaz crystals can be efficiently used as TL dosimeters.

The aim of the present work is to investigate the possibility of using the properties of the thermoluminescent emission (TL) of Brazilian natural topaz for dosimetric applications. Topaz is an aluminium fluorsilicate with general composition of Al2(SiO4)(F,OH)2 found with relative abundance in Brazil and in other parts of the world. Topaz from Santo Antonio do Jacinto, Minas Gerais. Brazil, was used in this work, in the form of pellets of topaz mixed with Teflon and composites made with topaz embedded in a glass matrix. The TL sensitivity was tested between 10(-4) and 10(4) Gy. The TL peak intensity increases with the dose before saturation, which occurs around 2 kGy. The peak intensity showed a strong dependence with radiation energy. The effect of visible light and the behaviour of the TL signals after successive irradiation-reading-annealing cycles are presented and discussed.