Abstract The Serra Branca pegmatite in northeastern Brazil is unique because of its megacrysts of bluish-green amazonite currently exploited for ornamental purposes and as high-quality gemstones. Here we analyze microtextural, spectroscopic, and geochemical data on specimens from two magmatic generations of amazonite from this pegmatite in order to characterize their mineralogy and propose a schematic evolution diagram for twinning during their development. The amazonite consists of intergrowths of the low microcline and low albite XRD varieties that evolved according to a twin coarsening process, in which the first generation (I-tg) of ± A/P twinning developed at the monoclinic-triclinic transformation, whereas the second generation (II-tg) gave rise mainly to ± A twins. The bluish-green color of the amazonite was preserved during the process of microcline twinning. In addition to the irrational II-tg twinning, which is typically found in microcline from anorogenic settings, the serra branca amazonite crystals also show elevated contents of Rb, Pb, Fe, Cs, and Tl in both generations, whereas albitic intergrowths present high concentrations of Fe, Pb, Sr, and Ga. Finally, our chemical and spectroscopic results are compatible with the hypothesis that Pb-water centers account for the bluish green color in amazonite.

ABSTRACT Although there are already available pineapple cultivars resistant to fusariosis, Brazilian production is based on the cultivar Pérola, susceptible to fusariosis. Studies with these resistant cultivars should prioritize the fulfillment of nutritional requirements, so that they express their productive potential and become viable options for producers. The objective of this study was to study the effects of foliar fertilizer compositions on the growth and yield of five micropropagated pineapple cultivars. The study was started in a greenhouse and at 210 days after transplanting, the seedlings were transferred to field conditions. The experimental design was in randomized blocks, in subdivided plots with three factors and four replications. The combination of the five pineapple cultivars (BRS Ajubá, IAC Fantástico, BRS Imperial, Pérola and BRS Vitória) and three leaf fertilizer compositions (NK, NPK and NPK + micronutrients) were randomized in plots and six evaluation periods consisted of subplots. Agronomic attributes were analyzed at the time of evaluation. The results obtained were subjected to analysis of variance by the F test. The Scott-Knott test was used for comparisons between cultivars and fertilization, and regression for the seasons, using the SISVAR program. Regardless of fertilization, cv. IAC Fantástico stood out in the majority of the evaluated characters, being superior to cv. Pérola, considered standard. The NK formula shows to be the best option for use as leaf fertilizer in the pineapple crop. The cultivar IAC Fantástico has good vegetative and productive characteristics, having the potential to be a viable option for cultivation in the state of Roraima.

RESUMO Embora já se disponha de cultivares de abacaxizeiro resistentes à fusariose, a produção brasileira é baseada na cultivar Pérola, susceptível à fusariose. Estudos com essas cultivares resistentes devem priorizar o atendimento das exigências nutricionais, para que elas expressem seu potencial produtivo e se tornem opções viáveis para os produtores. Objetivou-se estudar os efeitos de composições de adubo foliar no crescimento e produção de cinco cultivares de abacaxizeiro micropropagadas. O estudo foi iniciado em casa de vegetação e aos 210 dias após o transplantio, as mudas foram transferidas para o campo. O delineamento experimental foi em blocos casualizados, em parcelas subdivididas com três fatores e quatro repetições. A combinação das cinco cultivares de abacaxizeiro (BRS Ajubá, IAC Fantástico, BRS Imperial, Pérola e BRS Vitória) e três composições de adubo foliar (NK, NPK e NPK + micronutrientes) foram aleatorizadas nas parcelas e seis épocas de avaliação, nas subparcelas. Atributos agronômicos foram analisados nas épocas de avaliação. Os resultados obtidos foram submetidos à análise de variância pelo teste F. Foi empregado o teste de Scott-Knott para as comparações entre cultivares e adubação, e de regressão para as épocas, empregando-se o programa SISVAR. Independente da adubação, a cv. IAC Fantástico se destacou na maioria dos caracteres avaliados, sendo superior a cv. Pérola, considerada padrão. A fórmula NK mostra ser a melhor opção para utilização como adubo foliar na cultura do abacaxizeiro. A cultivar IAC Fantástico apresenta boas características vegetativas e produtivas, tendo potencial para ser uma opção viável para cultivo no estado de Roraima.

Abstract The Vieirópolis pegmatite field is characterized by amazonite pegmatites inserted in the Borborema Province. The Serra Branca pegmatite is hosted by the Serra Branca granites, which intruded partially the Serra Negra granites, and stands out by its amazonite mineralization. To comprehend the crystallization conditions and the source of this pegmatite and associated Serra Branca and Serra Negra granites, petrographic, mineral chemistry, geochronological and whole-rock geochemical data were used. The Serra Branca pegmatite is Cs-, Rb-, Pb-, Nb-, and Ta-rich. The Serra Branca granites (563 ± 2 Ma) are metaluminous to weakly peraluminous, crystallized under high fO2 conditions, pressure of 2.68-2.80 kbar and temperatures ranging from 667-670°C, with many zircon grains showing inherited cores of Paleoproterozoic ages. The Serra Negra granites (594 ± 4 Ma) comprises metaluminous granites crystallized under high fO2 conditions, temperatures within 711-751°C, pressure varying from 4.72 to 5.42 kbar. Both granites resulted from distinct partial melting degrees of a source similar to the Caicó Complex orthogneisses. The Serra Branca pegmatite geochemical data suggests that it was originated by extreme fractionation of the Serra Branca granites magma. The Serra Branca amazonite pegmatite is the first pegmatite mineralogically and geochemically characterized as Nb-Y-F (NYF)-type from the gadolinite subtype in the Borborema Province.

Abstract reflectance spectroscopy is a fast tool for mineral identification and classification. We conducted spectral characterization of elbaite samples (n = 30) from Seridó Pegmatite Province, Borborema Province, NE Brazil, using a FieldSpec portable instrument and geochemical data from electron probe microanalysis. Visual interpretation of reflectance spectra reveals the absorption features in the visible to near infrared (350-1,200 nm) range related to the electronic transition processes of iron (e.g., ~720, ~1,180 nm), copper (e.g., ~694, ~922 nm) and manganese (e.g., ~400, ~520 nm) ions. In general, electron probe microanalysis data show correlation with the absorption features related to chromophore elements (e.g., Cu, Fe, Mn), but the complex crystal structure of the tourmalines also accounts for the generation of absorption features. Vibrational processes in the short-wave infrared (1,200-2,500 nm) spectral range appear associated with Mn-OH, OH, Al-OH, H2O and B-OH bonds. A statistical approach, using principal component analysis, was chosen for distinguishing tourmalines of different composition. We discriminated tourmalines characterized by green, blue, blue-green, red/purple colors, as well as the colorless ones. This included the Paraíba tourmaline, a high value variety of elbaite that is the focus of exploration carried out in Seridó Pegmatite Province.

Abstract The Paraná deposit, located at Southwestern Rio Grande do Norte state, in Brazil, is one of the few emerald deposits found at Borborema Province. The mineralization occurs in phlogopite schists and actinolite-phlogopite schists associated with pegmatites and albitites within the Portalegre Shear Zone. Unlike other well-known Brazilian emerald deposits, the mineralogy of Paraná emeralds has remained poorly investigated for the last 40 years. In this study, we conducted mineralogical characterization of theses emeralds through gemological testing, mineral chemistry, absorption and reflectance spectroscopy, and thermal analysis. The Paraná emeralds are bluish-green colored, characterized by high refractive index, several two-phase fluid inclusions and mica is the main mineral inclusion. Electron probe microanalysis and laser ablation-inductively coupled plasma-mass spectrometry analyses detected the presence of Fe2+ (0.43-1.94 wt.% FeO) and Cr3+ (0.04-0.14 wt.% Cr2O3) as the main chromophores replacing octahedral Al3+ in the crystal structure. In addition, substantial amounts of MgO (0.40-2.72 wt.%), Na2O (0.50-1.81 wt.%), and Cs2O (0.07-0.44 wt.%) were also identified. The main causes for its coloration were attributed to Cr3+ absorption features in visible spectral range, which were corroborated by absorption and reflectance spectra. The presence of types I and II H2O at channel-sites was recorded in Fourier-transform infrared spectra and demonstrated by dehydration processes observed in different thermal and thermogravimetric analyses.

This article gathers together data on the occurrence, production and economic importance of gem deposits in Brazil, including specific information on the major deposits. Of the 100 or so different types of gemstones found in the country, the most important in terms of production and/or originality are tourmalines, topaz, opals, varieties of quartz (agate, amethyst and citrine) and emeralds. Brazil is also one of the only producers in the world of imperial topaz and Paraíba tourmaline. The country also produces diamonds, rubies and sapphires on a smaller scale. Gem production in Brazil is, for the most part, carried out by prospectors and a handful of mining companies, reducing the capacity of the government to control the production and sale of gemstones. Another factor that tends to drive the industry to operate outside the law is the high tax burden, which is as high as 53% on the sale of jewelry and 25% on uncut or polished stones. Owing to the geographical distribution of gemstone deposits and the enormous size of the country, Brazil is divided into four gem-producing areas. In the Northeast there are primarily deposits of emerald, amethyst, citrine, hyaline quartz, elbaite, aquamarine, garnet, morganite and opal. The Central region is characterized primarily by emerald and diamond deposits, whereas in the South deposits and occurrences of amethyst, citrine, agate and diamond are found. The East is characterized mainly by the presence of gemstones associated with pegmatites and hydrothermal veins, Plio-Pleistocene sedimentary placer deposits and isolated concentrations of diamonds. Gem production in Brazil mainly occurs in the states of Minas Gerais, Bahia, Rio Grande do Sul, Mato Grosso and Goiás. The State of Minas Gerais is the largest producer and exporter of gemstones in the country and is responsible for 74% of the official production, which includes imperial topaz, beryl, tourmaline, spondumene and brazilianite. The State of Bahia produces mainly emeralds, amethyst and aquamarines and is the second largest producer of uncut colored stones after the State of Grande do Sul, which is one of the most important producers in the world of two of these: namely agate and amethyst. The State of Mato Grosso produces garnet, topaz, zircon, diopside, varieties of quartz and tourmaline on a smaller scale. The State of Goiás mainly produces emeralds, along with garnet, topaz, quartz (citrine and amethyst) and tourmalines. Natural diamond production is also significant in Goiás and Mato Grosso, where diamonds have been being unearthed by prospectors since the beginning of the 20th century. At present, the best prospects for diamond production in these states are to be found in kimberlites. Of the wide diversity of gems produced, some, such as the Paraíba tourmalines and the opal from Piauí, are renowned around the world for their originality and gemological properties.

El presente artículo reúne datos de localización, producción e importancia económica de los yacimientos de piedras preciosas en Brasil, así como información específica para los yacimientos de mayor relevancia económica. Entre los aproximadamente 100 diferentes tipos de gemas que se encuentran en el país, las más importantes en cuanto a producción y/u originalidad, son turmalina, topacio, ópalos, las diversas variedades de cuarzo (ágata, amatista y citrino) y esmeralda. Además, Brasil es uno de los productores en el mundo de topacio imperial y turmalina Paraíba y produce diamante, rubí y zafro a pequeña escala. La producción brasileña de piedras preciosas se realiza generalmente por mineros independientes y por unas pocas empresas mineras, por lo que el Estado ejerce un escaso control oficial efectivo sobre la producción y comercialización de gemas. Otro factor que contribuye a esta informalidad es la elevada carga fiscal en el medio, que alcanzó el 53% del valor de las ventas de joyería y el 25% de las ventas de piedras preciosas naturales o lapidadas. Debido a la extensa distribución geográfica de los depósitos de gemas en Brasil, por el gran tamaño del país, éste está dividido en cuatro sub-provincias gemológicas. En la provincia del Nordeste destacan los depósitos de esmeralda, amatista, citrino, cuarzo hialino, elbaíta, aguamarina, granates, morganita y ópalo. La provincia Central se caracteriza principalmente por la ocurrencia de esmeraldas y diamantes, mientras que en la del Sur predominan los depósitos y las ocurrencias de amatista, citrino, ágata y diamantes. La provincia del Este, por su parte, se caracteriza principalmente por sus mineralizaciones en pegmatitas y vetas hidrotermales y por depósitos sedimentarios del Plio-Pleistoceno de placeres de diamante. La producción de piedras preciosas en Brasil se concentra en los estados de Minas Gerais, Bahía, Río Grande do Sul, Mato Grosso y Goiás. Minas Gerais es el mayor productor y exportador de piedras preciosas en el país, lo que representa 74% de la producción oficial, incluyendo topacio imperial, berilo, turmalina, espodumena y brasilianita. El estado de Baía produce principalmente esmeralda, amatista y aguamarina, siendo considerado el segundo mayor productor de gemas brutas tras el estado del Río Grande do Sul, uno de los más importantes productores mundiales de ágata y amatista. El Estado de Mato Grosso produce, a pequeña escala, granate, topacio, zircón, diópsido y variedades de cuarzo y turmalina. En Goiás destaca la producción de esmeraldas y de granate, topacio, cuarzo (amatista y citrino) y turmalina. En cuanto a los diamantes en bruto también merecen mención los yacimientos de Goiás y Mato Grosso, que son producidos desde principios del siglo XX por mineros independientes. Hoy en día, las mejores perspectivas para la producción de diamantes en esos estados provienen de kimberlitas. Entre la variedad de gemas producidas en Brasil, por su originalidad y propiedades gemológicas, destacan en el mundo la turmalina Paraíba y el ópalo del Piauí.

A mineralogia do solo constitui uma excelente ferramenta para o conhecimento e a avaliação da gênese do solo e do seu comportamento físico e químico, além de ser um dos parâmetros utilizados na distinção de classes do Sistema Brasileiro de Classificação de Solos e um indicativo da reserva potencial mineral de nutrientes para as plantas. Nesse contexto, este trabalho apresenta a caracterização mineralógica das frações cascalho, areia grossa e areia fina (sob lupa binocular e microscópio petrográfico) e das frações silte e argila (difratometria de raios X) de todos os horizontes do solo, e o estudo petrográfico da rocha matriz, a partir dos quais estabelece considerações sobre a evolução mineralógica de um Argissolo Vermelho-Amarelo, típico da Zona Úmida Costeira do Estado de Pernambuco. As frações grossas ao longo de todo o Argissolo estudado são constituídas, essencialmente, por quartzo (> 95 %) anguloso a muito anguloso, o que denota a ausência de transporte de material na formação desse tipo de solo. Foram observados fragmentos de rocha (constituídos por quartzo, feldspatos e minerais opacos), feldspatos e biotita que apresentam alteração intempérica mais evidente nos horizontes mais superficiais, além de minerais opacos, como magnetita e hematita, e traços de clorita, zircão, epidotos e apatita, todos de mineralogia compatível com a rocha matriz. A fração silte é constituída por minerais do grupo das micas, dos feldspatos, do quartzo e da caulinita, além da clorita observada apenas nos horizontes mais inferiores. A fração argila mostrou a mesma mineralogia da fração silte, sendo ainda detectados minerais interestratificados nos horizontes mais inferiores. A petrografia da rocha matriz mostrou que esta é um biotita-gnaisse de granulometria média, constituído por feldspatos (plagioclásio, pertita e microclina), quartzo, biotita e, como acessórios, epidotos, zircão e minerais opacos. A análise dos resultados permite concluir que o Argissolo estudado é autóctone, bem desenvolvido e altamente intemperizado devido às condições de clima, relevo e vegetação, apresentando baixa reserva potencial mineral de nutrientes para as plantas.

Soil mineralogy is an important tool to study and understand soil genesis and soil physical and chemical behavior. Furthermore, soil mineralogy is used as diagnostic criterion to define soil classes in the Brazilian System of Soil Classification and provides information on the potential soil mineral reserve of plant nutrients. In this context, this study presents the mineralogical characterization of gravel, fine and coarse sand fractions (under a binocular lens and petrographic microscope), and of the silt and clay fractions (by X ray diffraction) of all soil horizons, and the petrographic study of the parent rock, aiming to understand the mineralogical evolution of a typical Ultisol of the Coastal Humid Zone of Pernambuco State. The coarse fractions of the studied Ultisol are formed, essentially, by angular shaped quartz (> 95 %), demonstrating the absence of transported materials during soil formation. Rock fragments (formed by quartz, feldspars and opaque minerals), feldspars and biotite, with more evident weathering in the surface horizons, were also observed and are mineralogically compatible with the parent rock. The silt fraction is composed by micas, feldspars, quartz and kaolinite. Chlorite is only observed in the deeper horizons. The clay fraction has the same mineralogy as observed for the silt fraction, and still there are interstratified minerals in the bottom horizons. The parent rock is biotite-gneiss of medium granulometry, formed by feldspars (plagioclase, perthite and microcline), quartz and biotite, with epidotes, zircon and opaque minerals as accessory minerals. The results showed that the studied Ultisol is autochthonous and highly weathered, due to the humid tropical climatic conditions, and has a very low potential mineral reserve of plant nutrients.

A surdez profunda é uma deficiência que afeta a personalidade, o relacionamento e todo o estilo de vida do paciente. Incapacita os indivíduos de escutarem sons ambientes como sirenes e alarmes que constituem alerta em situações da vida diária e não permite a modulação vocal, tornando a voz esteticamente ruim. A prótese auditiva convencional é eficiente no tratamento de grande parte das deficiências auditivas, porém existem pacientes que não conseguem obter discriminação de palavras e sentenças mesmo com uma prótese auditiva potente. O implante coclear é a alternativa atual para estes pacientes. OBJETIVO: Avaliar o resultado auditivo dos pacientes adultos implantados com o implante coclear multicanal pelo Grupo de Implante Coclear da Disciplina de Otorrinolaringologia da Faculdade de medicina da Universidade de São Paulo. FORMA DE ESTUDO: Estudo de série. CASUÍSTICA E MÉTODO: Foram selecionados 61 pacientes com surdez profunda bilateral que utilizam o implante coclear multicanal por pelo menos seis meses e estudados os resultados auditivos através de testes de reconhecimento de palavras e sentenças. RESULTADOS: O PTA médio obtido pelos pacientes foi 38.7 dB NPS. A média em reconhecimento de sentenças em formato aberto foi de 71.3%, vogais em 86.5%, monossílabos em 52.60% e consoante medial em 52.6%. A maioria dos pacientes está apta ao uso do telefone. CONCLUSÃO: A avaliação auditiva obtida seis meses após a primeira programação do implante demonstra que pacientes de língua portuguesa obtêm excelentes resultados em testes de reconhecimento de palavras e sentenças em apresentação aberta, readquirindo uma audição útil.

Complete hearing loss is a very important handicap resulting in sensory deprivation and affecting an individual's personality, relationships and life style. Individuals with profound deafness are unable to hear environmental sounds as doorbells, telephones, traffic noises and sirens that are an important alert for dangerous situations in the daily life. They are also unable to hear their own voices and for this people with profound deaf do not modulate their voices. The hearing aids are the first choice to treat deafness, but there are patients with severe damage of the auditory systems who cannot receive a useful hearing from normal hearing aids. The cochlear implant is the alternative for patients that cannot have good discriminatory ability wearing a powerful hearing aid and wish or need a better hearing. AIM: To study the hearing results of the adult patients who are using a multichannel cochlear implant system at the Department of Otolaryngology - University of Sao Paulo. STUDY DESIGN: Series study. MATERIAL AND METHOD: We selected 61 patients with a severe bilateral hearing loss that have been using the cochlear implant for at least six months. The hearing evaluation performed after using the device for six months included word and sentence recognition tests. RESULTS: The PTA of four patients reached 38.7 dB. Speech perception tests showed 713% recognition of open set sentences, 86.5% of vowels and 52.60% of monosyllabic. Most of our patients are able to speak on the telephone. CONCLUSION: Most of patients showed excellent results in open-set sentence and word tests.

Introdução: Com o progresso tecnológico dos implantes cocleares, cada vez mais pacientes com audição residual útil são candidatos em potencial ao implante (Hodges et al., 1997). Apesar disso, não se sabe ao certo se a introdução dos eletrodos poderia destruir as estruturas auditivas envolvidas nessa audição residual. Objetivo: O objetivo deste estudo foi verificar a conservação da audição residual em pacientes usuários de implante coclear multicanal, comparando a audiometria pré e pós-operatória desses indivíduos. Forma de estudo: Clínico prospectivo randomizado. Material e método: Foram estudados 09 pacientes adultos com disacusia sensorioneural bilateral severa a profunda, usuários de Implante coclear Nucleus 22 e 1 paciente usuário de Implante Combi 40+. Resultado: No grupo estudado a conservação auditiva ocorreu em 50% dos indivíduos, quando considerado o critério de conservação de duas ou mais frequências médias (da fala) e em 80%, se for considerada audição também em frequências graves. Conclusão: A média de queda dos limiares tonais antes e após a cirurgia foi de 4 dB na orelha implantada e 0 dB na orelha contralateral.

Introduction: Technological development of Cochlear Implants allowed patients with residual hearing, that's to say, severe sensorineural hearing losses, to be considered as candidates (Hodges et al., 1997). Nevertheless, it is not clear whether the electrode array insertion may destroy remaining auditory structures. Aim: The purpose of this research was to verify the maitainance of residual hearing in multichannel cochlear implant users, by the comparison between the pre and post pure tone audiometry. Study design: Clinical prospective randomized. Material and method: Nine Nucleus 22 device and one Combi 40+ device users were evaluated. Results: In this sample hearing preservation was observed in 50% of the subjects, when considering the mid frequencies (speech frequencies) criterium of preservation. On the other hand, when the whole range of frequencies (including low frequencies) was considered as a criterium the preservation was revealed in 80% of the subjects. Conclusion: The average decrement in pure tone thresholds was 4 dB in the implanted ear and 0 dB in the contralateral ear.