25 research outputs found

    Disturbance of Ultisol soil based on interactions between furrow openers and coulters for the no-tillage system

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    The present study evaluated the effect of different associations between coulters and fertilizer furrow openers on soil disturbance, furrow depth and width, according to forward speed. The study was conducted on a farm in Santa Maria (Brazil/RS), in soil classified as sandy loam Ultisol. The experiment consisted of 24 combinations of treatments with three replications in a 2×3×4 factorial experiment. The combinations were formed by the interaction of the factors including: two types of furrow openers (hoe and double-disc), three types of coulters (no-coulter, smooth and offset fluted) and four levels of forward speed (1.11, 1.67, 2.22 and 2.78 m/s). Soil elevation and soil disturbance area profiles were obtained with the use of a micro profilometer, and disturbance values were calculated with the aid of computer software program Auto Cad. The disturbance area was not affected by speed; it was greater when using the hoe opener, and in association with the offset fluted coulter. Speed was inversely proportional to the depth of the furrows made by the hoe opener. Furthermore, the hoe caused the greatest furrow width (0.26 m) in comparison with the double-disc (0.24 m). The use of different coulters associated with furrow openers increased this variable (0.23 m for the no-coulter condition, 0.25 m with smooth and 0.26 m with offset fluted). The use of coulters combined with furrow openers reduces soil swelling, in approximately 8% for the smooth and 20% for the offset fluted

    Displasia cementária periapical: relato de dois casos

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    A displasia cementária periapical (DCP) é considerada uma alteração pseudotumoral de etiologia desconhecida. Essa patologia é assintomática e tem crescimento autolimitante. Os dentes afetados apresentam normalmente vitalidade pulpar e integridade da lâmina dura. Objetivo: Apresentar dois casos clínicos que demonstram a importância do conhecimento e correto diagnóstico da DCP. Relatos clínicos: Paciente M.I.S, de 61 Anos, Gênero Feminino, Leucoderma. Apresentou-se ao setor de Endodontia, para avaliação, ao exame radiográfico foi constatada imagem radiopaca nos ápices de incisivos inferiores. Ao teste de sensibilidade ao frio houve resposta negativa, então foi realizado o teste em outras áreas da mandíbula, também com resposta negativa, tornando o teste inconclusivo. Com base nas informações obtidas pelos exames clínico e radiográfico, foi diagnosticada a DCP. Realizado controle clínico e radiográfico, não houve alterações significativas. Paciente H.N.P.N, de 22 Anos, Gênero Feminino, Leucoderma. Apresentou-se ao setor de Endodontia, para avaliação, ao exame radiográfico foi constatada imagem radiopaca na região perirradicular de canino e primeiro pré-molar inferiores do lado esquerdo. Ao teste de sensibilidade ao frio, houve resposta positiva. Com base nas informações obtidas pelos exames clínico e radiográfico, foi diagnosticada a DCP. Realizado controle clínico e radiográfico, não houve alterações significativas. Conclusão: Devido as suas características radiográficas, a DCP pode ser confundida com lesões inflamatórias de origem endodôntica. Intervenções endodônticas desnecessárias podem ocorrer por isso o cirurgião-dentista deve estar atento quanto à vitalidade pulpar e a integridade da lâmina dura dos dentes envolvidos, para o correto diagnóstico

    Plug apical com MTA em dente adjacente à área da fissura labiopalatina

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    O tratamento endodôntico de dentes com forame apical amplo requer consideração especial, devido ao risco de extravasamento do material obturador nos tecidos periapicais durante a obturação, de maneira relevante em áreas próximas às fissuras labiopalatinas. A criação de uma barreira apical é indicada em casos de difícil travamento do cone principal e consequente deficiência do selamento apical. O MTA em decorrência de suas excelentes propriedades biológicas, é o material de escolha para permanecer em contato com tecidos periodontais e periapicais, fazendo parte do arsenal endodôntico especificamente nestes casos de ápice aberto para a confecção de plug apical. Relato clínico: Indivíduo do gênero feminino, com fissura labiopalatina bilateral transforame, a distal dos dentes 11 e 21; compareceu no setor de endodontia do Hospital de Reabilitação de Anomalias Craniofaciais (HRAC-USP), apresentando necrose pulpar do dente 21. Na primeira sessão foi realizado o acesso cirúrgico, neutralização do conteúdo séptico/tóxico em sentido corono-apical, odontometria, biomecânica, curativo intracanal (pasta Calen) selamento provisório com cimento de ionômero de vidro. Na segunda sessão, foi realizada a obturação onde ocorreu extravasamento de material obturador, verificado através da radiografia comprobatória; justificando sua remoção e nova obturação, com prévia confecção de plug apical com MTA. Foi realizada proservação aos 6 meses pós tratamento endodôntico. Conclusão: neste caso, o plug apical com MTA possibilitou a obturação final do canal radicular com segurança, pela confecção de um anteparo apical, evitando extravasamento de material obturador e preservando a área de fissura labiopalatina

    Root canal treatment of maxillary incisors with heterotopic alterations: clinical case report

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    Aim: Cleft lip and cleft palate are the most common congenital craniofacial malformations. Dentistry plays an important role in the treatment of these patients since this defect comes associated with dental problems. Those alterations can implicate the teeth dimensions, morphology, location, quantity and structure. The endodontic strategy in teeth with challenging locations in the dental arch is a distinctive and major challenge both for diagnostics and treatment. In many situations, technical complications may lead to failure. The aim of this study is to describe particular peculiarities of root canal procedure in a special case which the patient presented location and dental alterations in maxillary incisors. This condition requires some modifications on the conventional endodontic therapy. An incorrect dental position and the presence of orthodontic appliances can contribute to the overlapping images throughout the radiographic procedures. The endodontic treatment planning of the endodontic case was examined through periapical radiographs and cone beam computed tomography. The endodontic access cavity was developed by the buccal surface due to the encountered difficulties by the intrusion and palatal direction of the anterior dental elements in the maxillary arch. The following operative endodontic steps as chemico-mechanical preparation and obturation were performed and considered satisfactory. In the obturation proceeding was employed a biological controlled technique with active lateral condensation. Conclusion: The planning stage of the treatment based on careful clinical examination and adequate complementary diagnostics procedures is essential for the endodontic treatment success of teeth with heterotopic alterations

    Root canal treatment of maxillary incisors with heterotopic alterations: clinical case report

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    Aim: Cleft lip and cleft palate are the most common congenital craniofacial malformations. Dentistry plays an important role in the treatment of these patients since this defect comes associated with dental problems. Those alterations can implicate the teeth dimensions, morphology, location, quantity and structure. The endodontic strategy in teeth with challenging locations in the dental arch is a distinctive and major challenge both for diagnostics and treatment. In many situations, technical complications may lead to failure. The aim of this study is to describe particular peculiarities of root canal procedure in a special case which the patient presented location and dental alterations in maxillary incisors. This condition requires some modifications on the conventional endodontic therapy. An incorrect dental position and the presence of orthodontic appliances can contribute to the overlapping images throughout the radiographic procedures. The endodontic treatment planning of the endodontic case was examined through periapical radiographs and cone beam computed tomography. The endodontic access cavity was developed by the buccal surface due to the encountered difficulties by the intrusion and palatal direction of the anterior dental elements in the maxillary arch. The following operative endodontic steps as chemico-mechanical preparation and obturation were performed and considered satisfactory. In the obturation proceeding was employed a biological controlled technique with active lateral condensation. Conclusion: The planning stage of the treatment based on careful clinical examination and adequate complementary diagnostics procedures is essential for the endodontic treatment success of teeth with heterotopic alterations

    In Situ Compatibilization of Biopolymer Ternary Blends by Reactive Extrusion with Low-Functionality Epoxy-Based Styrene Acrylic Oligomer

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    [EN] The present study reports on the use of low-functionality epoxy-based styrene¿acrylic oligomer (ESAO) to compatibilize immiscible ternary blends made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polylactide (PLA), and poly(butylene adipate-co-terephthalate) (PBAT). The addition during melt processing of low-functionality ESAO at two parts per hundred resin (phr) of biopolymer successfully changed the soften inclusion phase in the blend system to a thinner morphology, yielding biopolymer ternary blends with higher mechanical ductility and also improved oxygen barrier performance. The compatibilization achieved was ascribed to the in situ formation of a newly block terpolymer, i.e. PHBVb- PLA-b-PBAT, which was produced at the blend interface by the reaction of the multiple epoxy groups present in ESAO with the functional terminal groups of the biopolymers. This chemical reaction was mainly linear due to the inherently low functionality of ESAO and the more favorable reactivity of the epoxy groups with the carboxyl groups of the biopolymers, which avoided the formation of highly branched and/or cross-linked structures and thus facilitated the films processability. Therefore, the reactive blending of biopolymers at different mixing ratios with low-functionality ESAO represents a straightforward methodology to prepare sustainable plastics at industrial scale with different physical properties that can be of interest in, for instance, food packaging applications.This research was funded by the EU H2020 project YPACK (Reference number 773872) and by the Spanish Ministry of Science, Innovation, and Universities (MICIU) with project numbers MAT2017-84909-C2-2-R and AGL2015-63855-C2-1-R. L. Quiles-Carrillo wants to thank the Spanish Ministry of Education, Culture, and Sports (MECD) for financial support through his FPU Grant Number FPU15/03812. Torres-Giner also acknowledges the MICIU for his Juan de la Cierva contract (IJCI-2016-29675).Quiles-Carrillo, L.; Montanes, N.; Lagaron, J.; Balart, R.; Torres-Giner, S. (2019). In Situ Compatibilization of Biopolymer Ternary Blends by Reactive Extrusion with Low-Functionality Epoxy-Based Styrene Acrylic Oligomer. Journal of Polymers and the Environment. 27(1):84-96. https://doi.org/10.1007/s10924-018-1324-2S8496271Babu RP, O’Connor K, Seeram R (2013) Prog Biomater 2:8Torres-Giner S, Torres A, Ferrándiz M, Fombuena V, Balart R (2017) J Food Saf 37:e12348Quiles-Carrillo L, Montanes N, Boronat T, Balart R, Torres-Giner S (2017) Polym Test 61:421Zakharova E, Alla A, Martínez A, De Ilarduya S, Muñoz-Guerra (2015) RSC Adv 5:46395Steinbüchel A, Valentin HE (1995) FEMS Microbiol Lett 128:219McChalicher CWJ, Srienc F (2007) J Biotechnol 132:296Reis KC, Pereira J, Smith AC, Carvalho CWP, Wellner N, Yakimets I (2008) J Food Eng 89:361Vink ETH, Davies S (2015) Ind Biotechnol 11:167John RP, Nampoothiri KM, Pandey A (2006) Process Biochem 41:759Madhavan Nampoothiri K, Nair NR, John RP (2010) Biores Technol 101:8493Garlotta D (2001) J Polym Environ 9:63Lim LT, Auras R, Rubino M (2008) Prog Polym Sci 33:820Quiles-Carrillo L, Montanes N, Sammon C, Balart R, Torres-Giner S (2018) Ind Crops Prod 111:878Quiles-Carrillo L, Blanes-Martínez MM, Montanes N, Fenollar O, Torres-Giner S, Balart R (2018) Eur Polym J 98:402Witt U, Müller R-J, Deckwer W-D (1997) J Environ Polym Degrad 5:81Siegenthaler KO, Künkel A, Skupin G, Yamamoto M (2012) Ecoflex® and Ecovio®: biodegradable, performance-enabling plastics. In: Rieger B, Künkel A, Coates GW, Reichardt R, Dinjus E, Zevaco TA (eds) Synthetic biodegradable polymers. Springer, Berlin Heidelberg, p 91Jiang L, Wolcott MP, Zhang J (2006) Biomacromol 7:199Brandelero RPH, Yamashita F, Grossmann MVE (2010) Carbohyd Polym 82:1102Muthuraj R, Misra M, Mohanty AK (2014) J Polym Environ 22:336Porter RS, Wang L-H (1992) Polymer 33(10): 2019Koning C, Van Duin M, Pagnoulle C, Jerome R (1998) Prog Polym Sci 23:707Muthuraj R, Misra M, Mohanty AK (2017) J Appl Polym Sci 135:45726Ryan AJ (2002) Nat Mater 1:8Wu D, Zhang Y, Yuan L, Zhang M, Zhou W (2010) J Polym Sci Part B 48:756Kim CH, Cho KY, Choi EJ, Park JK (2000) J Appl Polym Sci 77:226Supthanyakul R, Kaabbuathong N, Chirachanchai S (2016) Polymer 105:1Na Y-H, He Y, Shuai X, Kikkawa Y, Doi Y, Inoue Y (2002) Biomacromolecules 3:1179Zeng J-B, Li K-A, Du A-K (2015) RSC Adv 5:32546Xanthos M, Dagli SS (1991) Polym Eng Sci 31:929Sundararaj U, Macosko CW (1995) Macromolecules 28:2647Milner ST, Xi H (1996) J Rheol 40:663Villalobos M, Awojulu A, Greeley T, Turco G, Deeter G (2006) Energy 31:3227Torres-Giner S, Montanes N, Boronat T, Quiles-Carrillo L, Balart R (2016) Eur Polym J 84:693Lehermeier HJ, Dorgan JR (2001) Polym Eng Sci 41:2172Liu B, Xu Q (2013) J Mater Sci Chem Eng 1:9Eslami H, Kamal MR (2013) J Appl Polym Sci 129:2418Loontjens T, Pauwels K, Derks F, Neilen M, Sham CK, Serné M (1997) J Appl Polym Sci 65:1813Ojijo V, Ray SS (2015) Polymer 80:1Frenz V, Scherzer D, Villalobos M, Awojulu AA, Edison M, Van Der Meer R (2008) Multifunctional polymers as chain extenders and compatibilizers for polycondensates and biopolymers. In: Technical papers, regional technical conference—society of plastics engineers, p. 3/1678Utracki LA (2002) Can J Chem Eng 80:1008Al-Itry R, Lamnawar K, Maazouz A (2012) Polym Degrad Stab 97:1898Lin S, Guo W, Chen C, Ma J, Wang B (2012) Mater Des (1980–2015) 36: 604Arruda LC, Magaton M, Bretas RES, Ueki MM (2015) Polym Test 43:27Wang Y, Fu C, Luo Y, Ruan C, Zhang Y, Fu Y (2010) J Wuhan Univ Technol Mater Sci Ed 25:774Wei D, Wang H, Xiao H, Zheng A, Yang Y (2015) Carbohyd Polym 123:275Abdelwahab MA, Taylor S, Misra M, Mohanty AK (2015) Macromol Mater Eng 300:299Sun Q, Mekonnen T, Misra M, Mohanty AK (2016) J Polym Environ 24:23Torres-Giner S, Gimeno-Alcañiz JV, Ocio MJ, Lagaron JM (2011) J Appl Polym Sci 122:914Miyata T, Masuko T (1998) Polymer 39:5515Muthuraj R, Misra M, Mohanty AK (2015) J Appl Polym Sci 132:42189Ren J, Fu H, Ren T, Yuan W (2009) Carbohyd Polym 77:576Torres-Giner S, Montanes N, Fenollar O, García-Sanoguera D, Balart R (2016) Mater Des 108:648Jamshidian M, Tehrany EA, Imran M, Jacquot M, Desobry S (2010) Compr Rev Food Sci Food Saf 9:552Savenkova L, Gercberga Z, Nikolaeva V, Dzene A, Bibers I, Kalnin M (2000) Process Biochem 35:573Costa ARM, Almeida TG, Silva SML, Carvalho LH, Canedo EL (2015) Polym Test 42:115Zhang K, Mohanty AK, Misra M (2012) ACS Appl Mater Interfaces 4:3091Zhang N, Wang Q, Ren J, Wang L (2009) J Mater Sci 44:250Chinsirikul W, Rojsatean J, Hararak B, Kerddonfag N, Aontee A, Jaieau K, Kumsang P, Sripethdee C (2015) Packag Technol Sci 28:741Auras R, Harte B, Selke S (2004) J Appl Polym Sci 92:1790Sanchez-Garcia MD, Gimenez E, Lagaron JM (2008) Carbohyd Polym 71:235Sanchez-Garcia MD, Gimenez E, Lagaron JM (2007) J Plast Film Sheeting 23:133Lagaron JM (2011) Multifunctional and nanoreinforced polymers for food packaging. In: Multifunctional and nanoreinforced polymers for food packaging. Woodhead Publishing, Cambridge, p 

    Evaluation of the Travel to Interview Scheme (TIS) pilot

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