937 resultados para Stone carvers


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A pollen chase experiment was performed upon three Costa Rican populations of Witheringia solanacea to examine the breakdown of genetically enforced self incompatibility (SI) and the extent of embryonic inbreeding depression. Self-pollen was applied in the bud, with outcross pollen applied one day later, and outcross pollinations at both intervals as a control. A variety of responses were found among the populations. BOHS readily accepted self pollen and suffered from very low inbreeding depression. Monteverde and Las Cruces both have lower fruit set with self-pollination precedence indicating that bud pollinations can overcome the self-incompatibility response and that embryonic death due to inbreeding depression causes fruit failure. The treatment:control fruit set is higher for the Las Cruces plants indicating stronger SI response Self-precedence seeds from the Las Cruces plants are likely to be outcrossed. Self-precedence seeds from Monteverde are likely selfed.

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Efforts to estimate the magnitude of the incumbency effect in U.S. House elections and assess its political meaning have been complicated by two omitted-variables problems. First, in the absence of an adequate measure of incumbent prospects, estimates of the magnitude of the incumbency effect fail to control for selection effects associated with the decision incumbents make about whether to run for reelection. Strategic incumbents enter races they think they can win and withdraw when they expect to lose. The consequence is an upward bias in estimates of incumbents’ electoral advantages. Second, the normative implications of high reelection rates cannot be assessed without measuring incumbent quality, since a possible explanation for their electoral success is that incumbents are of high quality and doing a good job. We propose a strategy for measuring incumbent prospects and quality, demonstrate the strategic nature of incumbent and challenger entry, re-estimate the incumbency effect, and show that incumbent quality has an impact on electoral outcomes. Our conclusion is that incumbents’ advantages in House elections have been over estimated while the positive basis of incumbent safety is typically under appreciated.

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Hiperoxalúria ocorre após ressecção extensa do intestino delgado na presença de um colon intacto. De 1984 a 1997, 40 pacientes com ressecção de intestino delgado, extensão maior do que 30cm, foram estudados com o objetivo de se avaliar a prevalência de litíase renal nesta população e alterações metabólicas associadas. Sete pacientes, correspondendo a 17,5% da população em estudo, desenvolveram um ou mais cálculos renais durante o período de observação correspondendo a uma incidência de 3,1 casos por 100 pessoas/ano. Os pacientes foram então divididos em dois grupos. Grupo 1 formado por 33 pacientes com ressecção intestinal que não formaram cálculos renais durante o período de observação e o Grupo 2 com 7 pacientes que formaram um ou mais cálculos renais após a ressecção intestinal. A excreção urinária de oxalato foi, em média, maior no grupo 2, que desenvolveram litíase renal, comparado com o grupo 1, não formadores de cálculos renais (49,2±23,8 mg/24horas Vs 30,6±3,4 mg/24h, p=0,004). De forma oposta, o magnésio foi menor nos pacientes formadores de cálculos renais comparado com os pacientes não formadores de cálculos (54,5±17,9 mg/24horas Vs 94,9±8,5 mg/24horas, p=0,028), assim como o citrato também foi menor nos pacientes com cálculo renal, mas sem diferença do ponto de vista estatístico (265,9±55,8 mEq/24horas Vs 404,8±49,7mEq/24horas, P= 0,278). Este estudo mostra que novos cálculos urinários podem ser detectados em um número significativo de pacientes que se submetem à cirurgia de ressecção do intestino delgado, provavelmente associado ao aumento da excreção de oxalato e diminuição de, pelo menos, um dos inibidores da cristalização de oxalato de cálcio, o magnésio. Por isto, se torna importante a monitorização destes pacientes, regularmente, mesmo após vários anos da cirurgia. É importante a monitorização pelo menos do oxalato e magnésio, na urina de 24 horas, já que ambos estão associados a um maior risco de desenvolvimento de cálculos renais.

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This dissertation attempts to reach four goals: 1) to characterize the logistics development stage in two firms from the stone industry, an export firm and a non-export firm; 2) to identify the logistics functions performed by the firms themselves and the activities that are outsourced and also the reasons; 3) to describe the supply chain of the stone industry; 4) to apply a model called Leading Edge Logistics (BOWERSOX et al. 1992) to evaluate the current gaps between these firms in terms of organizational structure, information technology and performance system. This study has demonstrated that the export firm presented more adherence to the model compared to the non-export one, showing better entrepreneurial and operational performance. Furthermore, it has also confirmed the expectations generated by the conceptual model, as follow: the export firm, due to the more complex operational environment, represented by its involvement in a more competitive and demanding sector, i.e. the foreign trade market, has developed a greater level of sophistication of the logistical organization than the non-export one, achieving a better level of flexibility and therefore becoming more competitive.

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Perfis de alteração em basaltos com baixos teores de Ti02 (LTiB) da Parte Sudeste da Bacia do Paraná (SPB) associam-se a superfícies aplainadas, nos planaltos das Araucárias (Ab' Saber, 1973), entre altitudes de 950 m a 750 m (Vacaria) e 1000m a 920m (a Sul de Lages). Em domínios mais dissecados do relevo, que crescem de Este para Oeste, e nas encostas intensamente dissecadas destes planaltos a Sul (calha do rio Antas) e a Norte (calha do rio Pelotas), os perfis de alteração são truncados ou inexistentes. A associação dos perfis de alteração com superfícies geomorfológicamente mais antigas (aplainadas e elevadas) faz supor que o início dos processos de alteração seja correlativo às superfícies aplainadas, antigo e, provável mente, Terciário. As sequências de alteração mais completas localizam-se em morros de topo plano e apresentam as seguintes fácies: Rocha mãe, saprólito, alterito argiloso, alterito esferoidal, "stone line", coberturas móveis e solo atual. Químicamente os produtos de alteração intempérica dos basaltos são "lateritas" segundo definição de Schellmann (1981), com enriquecimento em Fe2D.3 e H20; perdas em Si02, FeO, MgO, CaO, Na20 e K20; prováveis pequenas perdas emA12D.3. No saprólito, os pedaços de rocha fragmentada permitiram a descrição das alterações hidrotermais refletidas nas para gêneses dos sítios intersticiais, constitui dos por materiais cristalinos e criptocristalinos. Os cristais de titanomagnetita aparecem com manchas azuis irregulares que sugerem variações cristaloquímicas contínuas dentro de um mesmo cristal, típicas da maghemitização. O alterito argiloso é sede de pseudomorfoses dos minerais magmáticos e hidrotermais. Esmectitas, ocupam os sítios das camadas mistas hidrotermais; halloysitas 7 e 10 Á são dominantes nos plasmas das pseudomorfoses de plagioclásios e plasmas ricos em ferro e sílica predominam nas pseudomorfoses de piroxênios. Observa-se a transição halloysita -caolinita desordenada rica em ferro estrutural nas partes superiores do conjunto. Os plasmas secundários são silico-aluminosos, nas partes baixas do conjunto, e predominantemente opacos no topo. Estes plasmas constituem-se de halloysita, litioforita (ou plasma rico em Mn), goethita e maghemita. O alterito esferoidal apresenta o núcleo de rocha e um córtex de cor amarelo -alaranjada em que se verifica a presença dominante da goethita aluminosa. Secundáriamente, aparecem cristobalita, maghemita e gibbsita. As coberturas móveis, são constitui das de plasma caolinítico e plasmas ricos em hematita e goethita. Aparecem ainda grânulos, pisólitos e nódulos herdados de antigas couraças desmanteladas. Os minerais, formados em condições lateritizantes, são os filossilicatos halloysita 7Á e lOÁ, caolinita desordenada e os óxidos e hidróxidos, hematita, goethita, gibbsita e litioforita.Observou-se que a mineralogia de alteração está intimamente associada à textura da rocha original. Encontram-se, ainda, nestes horizontes de alteração intempérica, a cristobalita (metaestável) e a titanomaghemita. As titanomaghemitas identificadas nos saprólitos e alteritos apresentam as características de maghemitização: diminuição da taxa 32(Fe+ Ti)/O, aumento de lacunas na malha cristalina e diminuição do parâmetro ~. Mg diminui com o intemperismo, Mn e AI se concentram nas fases magnéticas. A halloysita 7Á predomina sobre a lOÁ, na fração < 2Jlm, do alterito argiloso, alterito esferoidal e no sistema fissural. A caolinita predomina no horizonte "tacheté". No alterito esferoidal, ocorre também caolinita e esmectita. As argilas halloysíticas apresentam quatro morfologias: esferas, tubos, lamelas planares e cones. A halloysita forma-se preferencialmente à caolinita no córtex de alteração do alterito esferoidal e na fácies argilosa, constituindo um primeiro estágio de intemperismo. Os tubos e cones têm os menores teores de Fe2Ü3 enquanto as halloysitas planares têm os mais altos teores de Fe2Ü3. O teor de Fe das partículas esferoidais é variado. Os óxidos e hidróxidos destes perfis caracterizaram variações da atividade a água, de atividade da sílica dissolvida e temperatura, refletindo as paleocondições (climáticas) de formação destas coberturas fósseis.

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Este trabalho investiga basicamente a validade do Teste Illinois de Habilidades Psicolinguísticas -ITPA -instrumento de avaliação do desenvolvimento da linguagem infantil. Seus autores, S. Kirk e J.J. McCarthy (1961), utilizam o referencial teórico proposto por C. Osgood (1957), a ele incorporando o modelo derivado da Teoria da Informação, o que permite que, na prática clínica, o ITPA possa ser incluído no processo psicodiagnóstico como instrumento de avaliação dos problemas da comunicação em crianças entre três e dez anos. Os objetivos que conduzem e orientam o trabalho apresentado podem ser definidos em três níveis: 1) O que trata dos constructos e suas interrelaç6es -análise crítica da validade teóricado ITPA; 2) O que avalia sua condição de instrumento diagnóstico do desempenho escolar -sensibilidade discriminante do rendimento acadêmico; 3) O que trata da eficácia da prática psicopedagógica proposta pelo mesmo instrumento. O estudo sobre a validade teórica foi realizado com 931 crianças entre três e dez anos de idade, em processo de escolarização, frequentando creches, jardins de infância ou classes regulares da Rede de Ensino do Primeiro Grau no Município do Rio de Janeiro. Utilizou-se a técnica da Análise Fatorial, complementada por uma abordagem lógica que comprovaram algumas das dimensões propostas pelo referencial teórico de Kirk e McCarthy. Para a validade diagnóstica foram avaliadas 71 crianças com dificuldades no desempenho acadêmico, expressas através de conceitos de insuficiência ou deficiência de rendimento e seus resultados foram comparados com os de um subgrupo, aleatoriamente constituído de crianças que participaram do estudo anterior. Utilizou-se a técnica da Análise Discriminante chegando-se à seguinte conclusão: embora a validade de constructo do IIPA não tenha sido completamente confirmada num nível diagnóstico os resultados permitem identificar, com baixa margem de erro, as crianças que pertencem a um ou outro dos grupos de contraste. Quanto ao terceiro nível, foi feita ampla-revelação bibliográfica sobre investigações efetuadas com este instrumento no Brasil e no Exterior. Visou-se avaliar a eficácia da prática psicopedagógica utilizada quando desenvolvida à luz dos recursos de intervenção que o IIPA propõe. Concluiu-se que as pesquisas, até o presente momento efetuadas, não são suficientes para formar um juízo mais seguro da praxis educativa destinada à reabilitação das crianças com problemas da comunicação - o que constitui impedimento a seu desempenho acadêmico - em função das controvérsias que tais pesquisas apresentam.

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Nota: A autora agradece à Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) pela concessão de bolsa de estudos para o desenvolvimento deste projeto de pesquisa.

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The system in-Ceram Alumina, produced by VITA, consists in a technique of prepare of a substructure of ceramics to dental crowns. First burning is made in the alumina decanted by slip casting process under a stone die that reproduces the tooth prepared to receive a crown. In a second burning, alumina is infiltrated by vitreous system, giving to this set a high mechanic resistance. In this work, it s made a study of the composition of a new infiltrating material more used nowadays, giving to alumina desirable mechanics proprieties to its using like substructure of support to ceramic s crown used in the market today. The addition of Lanthanum oxide (frit A) and calcium oxide (frit B) was made in attempt to increase the viscosity of LZSA and to reduce fusion temperature. The frits were put over samples of alumina and took to the tubular oven to 1400ºC under vacuum for two groups (groups 1 and 2). For another two groups (groups 3 and 4) it was made a second infiltration, following the same parameters of the first. A fifth group was utilized like group of control where the samples of pure alumina were not submitted to any infiltrating process. Glasses manifested efficient both in quality and results of analysis of mechanic resistance, being perfectly compatible with oral environment in this technical requisite. The groups that made a second infiltration had he best results of fracture toughness, qualify the use in the oral cavity in this technical question. The average of results achieved for mechanic resistance to groups 1, 2, 3, 4 and 5 were respectively 98 MPa, 90 MPa, 144 MPa, 236 MPa and 23 MPa

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The sharp consumption of natural resources by the construction industry has motivated numerous studies concerning the application of waste to replace partially or fully, some materials, such as aggregates, thereby reducing the environmental impact caused by the extraction of sand and crushing process. The application of stone dust from crushing process arising as an aggregate for the production of Portland cement concrete is a viable alternative in view of the high cost of natural sands, in addition to the environmental damage which causes its operation to the environment. The stone dust has reduced cost compared to natural sand because it is produced in the beds of their own quarries, which are usually located close to major urban centers. This study examined the feasibility of using stone dust from the crushing of rock gneisses in the state of Bahia, replacing natural quartz sand. In the development of scientific study was conducted to characterize physical and chemical raw materials applied and molded cylindrical specimens , using as reference values Fck 20, Fck 25 and Fck 30 MPa ( resistance characteristic of the concrete after 28 days) in following compositions stone powder: 10%, 30%, 50 %, 100% and 100% with additive. The specimens were cured and subjected to the tests of compressive strength and water absorption, then the samples were subjected to the tests of X-ray diffraction and scanning electron microscopy. The results obtained showed that the composition with 10% stone powder showed the best results regarding the physical and mechanical tests performed, confirming the reduction in compressive strength and increased water uptake increased as the content of the powder stone in the concrete composition

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Researches have shown that the introduction of rubber in concrete improves the features of its deformability, as well as contributes to environmental disposal of waste generated in the tire retreading process. Furthermore, there is a high availability of limestone within RN and CE country. Ignorance about this stone, does not allow its wide use as aggregate, leaving, this abundant supply idle. A composite of limestone gravel, with proportions of tire rubber waste which could be used as concrete would be an alternative to concrete for low applications. Therefore, this research aims to evaluate the characteristics of concrete containing limestone gravel and proportions of little aggregate replacement (sand) by tire rubber waste. To this goal, the material components of the concrete were characterized, concrete specimens with limestone gravel were made, from the dash 1.0: 2.5: 3.5, varying the water/cement ratio, and inserting a commercial plasticizer, without a proportion of residue, known as reference. From this, concrete with and without the presence of the additive in the same proportions were chosen, as well as these with the use of granite gravel, for being the most used. Selected the references, to these, replacements of little aggregate (sand) were added replaced by rubber waste from the tire retreading process, treated with 1M NaOH in proportions from 5.0 to 20.0 % by mass, cured and exposed to the semiarid environment. The results indicate the possibility of using limestone gravel in the concrete composition with workability correction using plasticizer. There was a decrease in the mechanical properties of the concrete with increments of waste rubber, but there is an improvement in toughness and deformability of the composite, which makes it interesting for the construction of non-structural concrete floors, as well as, the rubber waste delayed the hardening process, continuing to gain resistance after 28 days

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Lithiasis is considered a public health issue due to its high prevalence and rates of recurrence. Objective: To identify risk factors for lithiasis in kidney stone patients from Fortaleza, Brazil. In the first stage of the study, the medical records of 197 patients with urinary lithiasis covering the period 1996 2006 were analyzed with regard to clinical and metabolic data. In the second stage, 340 kidney stones were submitted to morphological examination under 10x magnification. According to the external morphology and the cut surface, the stones were classified as pure or mixed, and major and minor components were identified. In addition, the stone fragments of 25 patients treated with lithotripsy were submitted to morphological analysis. In the third stage, a subsample of 50 stones was used in a double-blind comparison of morphological and chemical findings. Results were expressed as concordant, partly concordant (discordant for minor components) or discordant (discordant for major components). The average age of first symptoms was 35.8±13.3 years, with no significant difference between the genders. The male/female ratio was 1:1.7. Recurrence was reported in 53.3% of cases. The main metabolic changes observed were hypernatriuria (80.7%), hypercalciuria (48.7%), low urine volume (43.7%), hyperoxaluria (30.5%) and hyperuricosuria (17.3%). Pure stones represented 34.7% of the total sample of 340 stones. The most common route of elimination was spontaneous for pure stones (49.1%) and surgical for mixed stones (50.5%). Pure stones consisted most frequently of calcium oxalate (OxCa) (59.3%) and uric acid (UA) (23.7%), the former prevalent in women, the latter prevalent in men. The most frequently observed component in mixed stones was OxCa (67.1%), followed by carbapatite (11.2%) and struvite (7.9%). The main components were OxCa and UA for men, and carbapatite and struvite for women. Nearly half (48%) the 25 analyzed fragments were pure, consisting of calcium oxalate dihydrate (COD) (56%), calcium oxalate monohydrate (COM) (48%), phosphate (32%) and UA (20%). Four patients (16%) had infectious stones. In the chemical analysis of the subsample of 50 stones, the most 64 frequently observed major components were calcium (70%), oxalate (66%), ammonium (56%), urate (28%) and carbonate (24%). In the morphological analysis, the main components were calcium and magnesium phosphate (32%), COM (24%), UA (20%), COD (18%) and cystine (6%). Morphological and chemical findings were totally concordant for 38% of the stones, partly concordant in 52% and discordant in 10%. Conclusion: The risk factors for lithiasis in kidney stone patients from Fortaleza (Brazil) were hyperoxaluria, hypercalciuria with or without hypernatriuria, hyperuricosuria and low urine volume

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OBJECTIVE: Evaluating the kit-Bh performance in carrying out of breast biopsies. METHODS: They were randomly selected a sample of 30 patients with breast cancer undergoing mastectomy, based on the results of a pilot study from February 2008 to April 2010. They were excluded women with had not palpable, stone-hard consistency tumors, previous surgical manipulation or that contains liquid. Using the helicoid biopsy Kit (kit Bh) and an equipment Core biopsy with cannula and needle and 14 gauge respectively, it was collected a fragment of sound equipment in the area and in tumors in each specimen, totaling 120 fragments for histological study. For data analysis, it was defined a 95% confidence level and used the SPSS-13 version, the Kappa index and the parametric Student t test. RESULTS: Mean age of patients was 51.6 years (± 11.1 years). The infiltrating ductal carcinoma showed a higher incidence, 26 cases (86.7%). The Core biopsy had a sensitivity of 93.3%, specificity of 100% and accuracy 96.7%, while the helicoid biopsy had a sensitivity of 96.7%, specificity of 100% and accuracy 98.3%. By comparing the histology of tumors and the fragments of biopsies, there was high degree of agreement in diagnoses (kappa of 0.93 with p <0.05) CONCLUSION: Both devices provided the histological diagnosis of lesions with high accuracy. Results of this study showed that the helicoid biopsy is a reliable alternative in 22 the preoperative diagnosis of breast lesions. Further studies in vivo better will define the role of Kit Bh in the diagnosis of these lesions

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)