Abstract Introduction Chloroquine and hydroxychloroquine are antimalarial drugs widely used in the treatment of rheumatic diseases. With the global pandemic caused by the new coronavirus, there was an increase in the prescription of these drugs, which led to a major concern regarding their ototoxic effects. Objectives The objective of the present study was to assess existing scientific evidence about the toxic effects of chloroquine and hydroxychloroquine on the peripheral and/or central auditory system. Data Synthesis A systematic literature review was performed by searching the PubMed (Medline), Scopus, Web of Science, LILACS, and SciELO electronic databases, in a search of articles that fullfiled the predefined inclusion and exclusion criteria. The review was conducted in three phases and, in all of them, analyses were performed by two independent researchers. Disagreements were discussed with a third researcher until a consensus was reached. A total of 437 articles were found and 8 were included in this review. Seven of the included studies reported hearing loss in their samples and presented a diagnostic hypothesis of ototoxicity induced by chloroquine or hydroxychloroquine. The most common type of hearing loss was sensorineural, with varying laterality and degrees of severity. The most frequently used audiological test was pure tone audiometry, and only two studies assessed brainstem evoked responses. Conclusion The scientific evidence compiled in this research showed that chloroquine and hydroxychloroquine have an ototoxic effect in the peripheral auditory system. These drugs can cause cochlear damage, including changes in the stria vascularis and lesions in sensory hair cells.

ABSTRACT The aim of this study was to evaluate the physical quality of the soils by evaluating the variation of soil penetration resistance, resulting from tillage with chiseling in the planting row and in total area, and the possible interferences of the managements in sugarcane yield. The study was carried out in southeastern Brazil, in areas under Oxisol and Ultisol, which are the two soils with the greatest representativeness of sugarcane cultivation in the country. The treatments consisted of soil tillage in total area and localized tillage in the sugarcane planting row, with 10 replicates. Undisturbed soil samples were collected in the 0-0.10, 0.10-0.20, and 0.20-0.40-m soil layers in sugarcane rows and interrows in both soil types for penetration resistance determination in laboratory. Samplings were carried out at three times, the first after soil tillage, the second after sugarcane planting, and the third six months after planting. Compared to the system with tillage in total area, localized tillage promoted higher values of soil penetration resistance in sugarcane interrows. However, this was not enough to reduce the crop yield. In the planting row, there are no differences between tillage types for soil penetration resistance. Localized soil tillage in sugarcane crop is a conservation and sustainable alternative that can replace soil tillage in total area, not interfering in the PR determined in the crop row and not altering the stem yield, regardless of the soil type.

RESUMO JUSTIFICATIVA E OBJETIVOS: A dor é um sintoma frequente no ambiente hospitalar. O estudo objetivou identificar o impacto da dor aguda sobre as atividades de vida diária e analisar a adequação analgésica. MÉTODOS: Estudo transversal desenvolvido em seis unidades de um Hospital Universitário. Os pacientes foram avaliados quanto à presença e intensidade da dor e prejuízos às atividades de vida diária. A adequação analgésica foi avaliada pelo Índice de Manejo da Dor. A associação entre a dor e as características sociodemográficas e clínicas foi investigada por meio do teste Qui-quadrado. Um modelo de regressão logística foi aplicado para avaliar o impacto da intensidade da dor nas atividades. RESULTADOS: Foram avaliados 134 pacientes, com média de idade de 53 anos. No momento da entrevista 37 (27,6%) participantes referiram dor e 58 (45,7%) relataram dor nas 24h que antecederam a entrevista. A intensidade média da dor foi 6,6±2,4 e a dor foi mais frequente em pacientes do Pronto Atendimento, Unidade de Terapia Intensiva e Clínica Médica. Houve associação entre dor e sexo feminino e não foi encontrada associação com unidade de internação, diagnóstico e especialidade. A dor afetou a capacidade de comer (p=0,036) e dormir (p=0,008). A maior parte das prescrições (68%) estava inadequada à intensidade da dor. CONCLUSÃO: A frequência de dor foi alta e a incidência maior no sexo feminino, afetando de modo significativo a capacidade de comer e dormir. A prescrição de fármacos era inadequada à intensidade da dor em mais da metade dos pacientes, indicando a necessidade de aprimorar os protocolos de controle da dor.

ABSTRACT BACKGROUND AND OBJECTIVES: Pain is a frequent symptom in the hospital environment. The study aimed to identify the impact of acute pain on activities of daily living and to analyze analgesic adequacy. METHODS: Cross-sectional study carried out in six units of a University Hospital. Patients were assessed for the presence and intensity of pain and impact on activities of daily living. Analgesic adequacy was assessed by the Pain Management Index. The association between pain and sociodemographic and clinical characteristics was investigated using the Chi-square test. A logistic regression model was applied to assess the impact of pain intensity on activities. RESULTS: 134 patients, mean age 53 years, were evaluated. At the moment of the interview 37 (27.6%) participants reported pain and 58 (45.7%) reported pain in the 24 hours before the interview. The average pain intensity was 6.6±2.4 and the pain was more frequent in patients in the Emergency Department, Intensive Care Unit and Internal Medicine. There was an association between pain and the female sex and there was no association with hospitalization unit, diagnosis, and specialty. Pain affected the ability to eat (p=0.036) and sleep (p=0.008). Most prescriptions (68%) were unsuitable for pain intensity. CONCLUSION: Frequency of pain was high, was more prevalent in women, and significantly impaired the ability to eat and sleep. Inadequacy of the analgesic regimen regarding intensity of pain was found in more than half of the patients, indicating that it's necessary to improve pain control in the hospital environment.

ABSTRACT The objective of this study was to evaluate the influence of minerals in the clay fraction on physical attributes of Yellow Ultisol cultivated with sugarcane and prepared with two different treatments: chiseling across the entire area and chiseling only in planting rows. The samples were collected from four layers of soil at eight months after planting. We assessed the texture of the soil, levels of iron extracted by dithionite-citrate-bicarbonate (DCB) and ammonium acid oxalate (AAO), ratio of kaolinite/(kaolinite + gibbsite), soil bulk density, and soil penetration resistance. The first area showed a higher ratio of kaolinite/(kaolinite + gibbsite) and the second area had greater levels of iron extracted by DCB. Levels of iron extracted by DCB were inversely correlated with soil bulk density and penetration resistance, while the kaolinite/(kaolinite + gibbsite) ratio was directly correlated with soil bulk density and penetration resistance. The area with a greater kaolinite/(kaolinite + gibbsite) ratio had higher values of soil bulk density and soil penetration resistance and the area with higher levels of iron showed lower values of soil bulk density and soil penetration resistance. The mineralogy influenced the soil's physical attributes, while soil preparation treatments did not.

ABSTRACT This study aimed to evaluate the effects of zinc oxide and a low level of encapsulated zinc oxide, with or without dietary fiber, on the performance and intestinal health of weaned piglets. A total of 112 piglets were used, divided into four treatment groups: basal diet with zinc oxide (ZnO); basal diet with zinc oxide and dietary fiber (ZnO+DF); basal diet with encapsulated low zinc oxide (LZnOE); and basal diet with LZnOE and DF (LZnOE+DF). Piglets were challenged with E . coli K88 + , weighed weekly and the fecal score was evaluated daily. One pig per pen was slaughtered to evaluate the production of volatile fatty acids, intestinal microbial populations, intestinal morphology, and digestibility. The encapsulated zinc resulted in lower body weight and average daily gain, but, when associated with dietary fiber, had similar results to zinc oxide. Until 49 days of age, zinc oxide reduced diarrhoea ( p < 0.05). At 63 days of age the piglets subjected to LZnOE+DF treatment had lower diarrhoea than the pigs subjected to LZnOE treatment but higher than the ZnO and the ZnO+DF groups. Final weight and incidence of diarrhoea of pigs receiving LZnOE was worse than ZnO. LZnOE associated with DF provided the same final weight of piglets from the ZnO group.

Resumo Este artigo tem por objetivo percorrer a historicidade da metodologia da Análise do Discurso fundada por Michel Pêcheux para a compreensão e reflexão crítica de seus modos de fazer análise, considerando a especificidade da teoria em sua implementação no contexto francês e sua reformulação e desenvolvimento no contexto brasileiro. Como possível aplicação dos procedimentos metodológicos atualmente praticados na área, é desenvolvida a análise do discurso feminista em páginas de rede social online. A discussão propõe, então, que se trabalhem os pressupostos desenvolvidos no âmbito da teoria materialista do discurso entre os processos de paráfrase e polissemia. Com este estudo, observa-se que a AD parte de uma concepção não-positivista de cientificidade para definir seus procedimentos metodológicos.

Abstract This article aims at go through the historicity of the methodology in the Discourse Analysis founded by Michel Pêcheux in order to understand and make a critical reflection on the ways analysis is made, considering the specificity of the theory in its insertion in the French context and its reformulation and development in the Brazilian context. As a possible applicability of the methodological procedures currently developed in the field, an analysis of the feminist discourse in the online social media is proposed. The discussion has the proposal of working with the materialistic theory of the discourse between the paraphrase and polysemy processes. With this study, it is observed that the DA has a non-positivist conception of scientificity to define its methodological procedures.

Resumen Este artículo tiene el objetivo de recurrir la historicidad de la metodología del Análisis del Discurso fundada por Michel Pêcheux para la comprensión y reflexión crítica de sus modos de hacer análisis, considerando la especificidad de la teoría en su implementación en el contexto francés, y su reformulación y desarrollo en el contexto brasileño. Como posible aplicación de los procedimientos metodológicos actualmente practicados en el área, el análisis del discurso feminista es desarrollado en la red social en línea. La discusión propone, entonces, que se trabajen los supuestos desarrollados en el ámbito de la teoría materialista del discurso entre los procesos de paráfrasis y polisemia. Con este estudio se observa que el AD parte de una concepción no-positivista de cientificidad para definir sus procedimientos metodológicos.

RESUMO Objetivo: investigar protocolos utilizados pela Fonoaudiologia para avaliação da amamentação. Métodos: trata-se de uma revisão integrativa da literatura que objetiva sintetizar evidências disponíveis sobre a avaliação da amamentação no período de 2002 a 2015. Os critérios de inclusão foram artigos científicos que abordassem avaliação da amamentação realizada por fonoaudiólogos, publicados em inglês e português. Trabalhos que não apresentaram resumos na íntegra foram excluídos. Resultados: foram encontrados 140 estudos, dos quais 134 foram excluídos. As seis publicações restantes realizaram avaliação da mamada e foram incluídas neste estudo. Identificaram-se quatro instrumentos de avaliação da amamentação. Os artigos selecionados objetivaram avaliar o conhecimento das mães sobre amamentação e sua relação com a linguagem, a primeira mamada do bebê prematuro, descrever condições iniciais da amamentação, relacionar amamentação com oferta do copo/mamadeira e avaliar características orofaciais e amamentação. Os protocolos avaliaram aspectos do estado de consciência, comportamento e posicionamento do bebê, comportamento da mãe ao amamentar, características da mama, da pega e ordenha e condições após a amamentação. Conclusão: são escassos os estudos na Fonoaudiologia que utilizam protocolos padronizados e validados para avaliação da amamentação. O enfoque maior está na avaliação dos bebês prematuros. Sugere-se que novos estudos sejam realizados, especialmente com foco em validar instrumentos.

ABSTRACT Objective: to investigate protocols used by Speech Therapists to evaluate breastfeeding. Methods: this is an integrative literature review that aims to synthesize available evidence on the evaluation of breastfeeding, from 2002 to 2015. The inclusion criteria were scientific articles that approached breastfeeding evaluation performed by Speech Therapists, published in English and Portuguese. Papers that did not present summaries in their entirety were discarded. Results: a total of 140 studies were found, 134 being excluded. The remaining six publications evaluated breastfeeding and were included in the study with four instruments. The articles selected aimed at evaluating the mothers' knowledge about breastfeeding and its relation to language, the first feeding of the premature baby, describing the initial conditions of breastfeeding, relating breastfeeding to the cup/bottle supply and evaluating orofacial characteristics and breastfeeding. The protocols evaluated aspects of the infant's state of consciousness, behavior and positioning, mother's breastfeeding behavior, breast characteristics, latching and milking, and conditions after breastfeeding. Conclusion: there are few studies in Speech Therapy that use standardized and validated protocols for breastfeeding evaluation. The major focus is on the evaluation of preterm infants. It is suggested that new studies be performed, especially with a focus on validating instruments.

Abstract The aim of this study was to conduct a systematic review and meta-analysis to assess the clinical outcomes of dental implants placed in previously early and late implant failed sites. An electronic literature search was conducted in several databases for articles published up to February 2018. Human clinical trials that received at least one implant in a previously failed site were included. Hence, the PICO question that was aimed to be addressed was: Do patients undergoing implant replacement (second and third attempts) in previous failed sites have survival rates similar to implants placed at first attempts? A random effects model was used to calculate survival weighted means and corresponding 95% Confidence Intervals (CI) among studies. Eleven studies of low to moderate methodological quality were included in this review. Implants placed in sites with history of one and two implant failures had a weighted survival rate (SR) of 88.7% (95%CI 81.7-93.3) and 67.1% (95%CI 51.1-79.9), respectively. Implants placed in sites with a previous early failure revealed a weighted SR of 91.8% (95%CI 85.1-95.6). First implants presented higher SR than implants placed in sites with one or two previous implant failures. In contrast, implants placed in sites with one and two implant failures had similar SR. Within its limitations, this review suggests that replacement implants have moderate SR. Larger prospective studies with well-defined criteria for early and late implant failure are necessary to confirm and expand on these results.

Resumo: O presente trabalho tem como objetivo traçar um panorama do modo pelo qual elementos presentes no âmbito da pesquisa e ensino de ciências e matemática dialogam com aspectos emergentes da Educação do Campo. Metodologicamente realizou-se uma revisão de literatura em atas de eventos e periódicos nacionais. Identificou-se, inicialmente, a natureza dos artigos e o nível de ensino abrangido por eles. A análise dos estudos selecionados foi orientada pelos seguintes focos: Relação com a Escola; Pressupostos teórico-metodológicos; Relação com o contexto; Relação com a conceituação científica. Sinaliza-se, assim, a diversidade de perspectivas teóricas e metodológicas em discussão, o que implica também em diferentes maneiras de entender o papel da escola, as relações com o contexto do campo e o papel da conceituação científica.

Resumen: El presente trabajo tiene el objetivo de trazar un panorama del modo por lo cual los elementos presentes en el ámbito de la investigación y enseñanza de ciencias y matemáticas dialogan con aspectos emergentes de la Educación del Campo. Metodológicamente, se realizó una revisión de la literatura en actas de eventos y periódicos nacionales. Se identificaron, inicialmente, la naturaleza de los artículos y el nivel de enseñanza comprendido por ellos. Él análisis de los estudios seleccionados fue orientado por los siguientes focos: Relación con la Escuela; Presupuestos teórico-metodológicos; Relación con el contexto; Relación con la conceptuación científica. Se señala, así, la diversidad de perspectivas teóricas y metodológicas en discusión, lo que comprende también diferentes modos de entender el papel de la escuela, las relaciones con el contexto del campo y el papel de la conceptuación científica.

Abstract: This paper aims to provide an overview of how aspects related to “Educação do Campo” {Education for and by the countryside} have been explored in the literature, particularly in Science and Mathematics Teaching. A literature review was carried out in event records and Brazilian journals. First, it was identified the nature of the paper and the educational level they were dealing with. Then, the analysis of selected studies was centered on the following focuses: Relationship with school; Theoretical and methodological assumptions; Relationship with context; Relationship with the scientific knowledge. From that, it is pointed out the diversity of theoretical and methodological perspectives in discussion, which also involves different ways of understanding the role of the school, the relationship with the countryside context and the role of scientific conceptualization.

RESUMO: Este trabalho pretende favorecer reflexões de ordem teórico-metodológica sobre práticas contextualizadas na formação inicial de professores e no ensino de ciências a partir da perspectiva educacional de Paulo Freire, tendo como base sua obra Extensão ou Comunicação?. Os elementos apontados como possibilidades de abordagem contextualizada não são conclusivos, mas, sim, reflexões que abrem caminhos para um trabalho contextualizado na formação de professores e no ensino de ciências, especialmente no que se refere a romper com uma formação pautada nos pressupostos da racionalidade técnica. Em linhas gerais, ressalta-se a contribuição da perspectiva freireana na superação de concepções extensionistas de ensino.

RESUMEN: Este trabajo pretende favorecer reflexiones de orden teórico y metodológico sobre prácticas contextualizadas en la formación inicial de profesores y en la enseñanza de las ciencias a partir de la perspectiva educacional de Paulo Freire. La propuesta está basada en la obra del autor Extensión o comunicación?. Los elementos apuntados como posibilidades de abordaje contextualizada no son conclusivos, pero, sí, reflexiones que abren caminos para un trabajo contextualizado en la formación de profesores y en la enseñanza de las ciencias, especialmente acerca el rompimiento con una formación pautada en los presupuestos de la racionalidad técnica. En síntesis, se resalta la contribución de la perspectiva freireana en la superación de conceptos extensionistas de enseñanza.

ABSTRACT: This work proposes to support theoretical and methodological reflections on contextualized practice in the initial teacher training and in teaching Science, from Paulo Freire's educational perspective. The proposal builds on the work Extension or Communication?, from the aforementioned author. The elements identified as contextualized approach possibilities are not conclusive, but they are reflections that open paths for a work contextualized in teacher's training and science education, especially about cutting off training guided in technical rationality assumptions. In general, the contribution is that it highlights Freire's perspective in overcoming educational extension conceptions.

RESUMO CONTEXTO: Linfoma esplênico difuso da polpa vermelha, de linfócitos B pequenos, é uma doença rara, representando menos do que 1% de todos os linfomas não Hodgkin. Essa entidade é caracterizada por envolvimento de sinusoides da medula óssea e sangue periférico. A maioria dos casos está em estádio avançado ao diagnóstico. Sua patogênese ainda é pouco compreendida. RELATOS DE CASOS: Reportamos dois pacientes com vírus da hepatite B (HBV) crônica não replicante que desenvolveram linfoma esplênico difuso da polpa vermelha, de linfócitos B pequenos. Ambos estavam em estádio IV ao diagnóstico e evoluíram com doença agressiva. Ambos alcançaram resposta completa com a quimioterapia, porém um deles evoluiu a óbito por intercorrências infecciosas durante o transplante de medula óssea e o outro optou por não realizar o transplante e encontra-se sem evidência de doença até os dias atuais (três anos após tratamento). Alguns estudos demonstraram a possível associação entre linfomas não Hodgkin B e HBV. Entretanto, o mecanismo pelo qual esse vírus oncogênico interage com linfoma não Hodgkin B ainda é pouco compreendido. HBV é linfotrópico e pode se inserir no genoma do receptor, causando superexpressão de oncogenes e downregulation de genes supressores tumorais. Portanto, o estímulo crônico pelo HBV pode aumentar a proliferação de células B, promovendo expansão monoclonal dessas células, resultando em malignidade. CONCLUSÃO: HBV pode estar implicado na patogênese desse linfoma, entretanto, uma associação direta entre essas duas entidades não pôde ser provada no presente estudo e investigações adicionais são necessárias.

ABSTRACT CONTEXT: Splenic diffuse red-pulp small B-cell lymphoma is a rare disease, representing less than 1% of all non-Hodgkin lymphomas (NHL). This entity is characterized by involvement of bone marrow sinusoids and peripheral blood. The majority of cases are at an advanced stage when diagnosed. Its pathogenesis is still poorly understood. CASE REPORTS: We report on two patients with chronic non-replicating hepatitis B virus (HBV) who developed splenic diffuse red-pulp small B-cell lymphoma. Both of them were in stage IV at diagnosis and evolved with aggressive disease. Both of them achieved a complete response through chemotherapy, but one of them died due to infectious complications during bone marrow transplantation. The other decided not to undergo transplantation and continues not to show any evidence of disease today (three years after treatment). Some studies have shown a possible association between B-cell NHL and HBV. Nonetheless, the mechanism through which this oncogenic virus interacts with B-cell NHL is still poorly understood. HBV is lymphotropic and may insert into the host's genome, thus causing overexpression of oncogenes and downregulation of tumor suppressor genes. Therefore, chronic stimulation by HBV can increase B-cell proliferation, which promotes monoclonal expansion of these cells and results in malignancy. CONCLUSION: HBV may be implicated in the pathogenesis of this lymphoma, although no direct association between these two entities could be proved in the present study. Further investigations are necessary.

RESUMO Introdução: Necrose de medula óssea (NMO) é uma entidade rara, frequentemente não diagnosticada e mais comumente associada a doenças hematológicas. Metodologia: Realizou-se revisão da literatura na base de dados do PubMed, utilizando o termo "necrose de medula óssea". Foram encontrados 25 artigos em inglês e 65 relatos de caso. Resultados e discussão: A fisiopatologia da NMO não é bem elucidada e parece estar associada a lesão vascular com consequente hipóxia celular por desbalanço na oferta de oxigênio e nutrientes. O fator de necrose tumoral alfa (TNF-α) provavelmente também está implicado na lesão endotelial e nos sinusoides da medula óssea. Sugere-se o diagnóstico pela presença de anemia, trombocitopenia, reação leucoeritroblástica, níveis elevados de desidrogenase lática e fosfatase alcalina. Aspirado e biópsia de medula óssea e ressonância nuclear magnética são os principais exames diagnósticos. As únicas possibilidades terapêuticas são tratamento da causa de base e medidas suportivas. Conclusão: O ponto mais importante no manejo da NMO é a busca por condições neoplásicas associadas.

ABSTRACT Introduction: Bone marrow necrosis (BMN) is a rare pathologic entity that is commonly undiagnosed, and often associated with hematologic diseases. Methodology: We conducted a literature review at PubMed using "bone marrow necrosis" as key words. Our search retrieved 25 articles written in English, and a further 65 case reports. Results and discussion: BMN pathophysiology is not well understood, but appears to be associated with vascular injuries that lead to oxygen and nutrient deprivation. Destructive tumor necrosis factor alpha (TNF-α) activity is also likely involved in the development of endothelial and bone marrow sinusoidal lesions. Diagnoses of BMN are commonly indicated by anemia, thrombocytopenia, high levels of lactic dehydrogenase and alkaline phosphatase, and the identification of leukoerythroblastic reactions. Bone marrow (BM) aspirate and biopsy, and magnetic nuclear resonance imaging are the main diagnostic options. The only available treatments are those directed against the primary cause, with associated supportive care for what is ordinarily a rapidly lethal state. Conclusion: The search for an underlying associated malignancy is important for the management of BMN.

Este trabalho tem como foco analisar e discutir as compreensões de estudantes do curso de Licenciatura em Educação do Campo da Universidade Federal de Santa Catarina (UFSC) a respeito da temática dos agrotóxicos no ensino de Ciências. Para apreensão das compreensões dos estudantes aplicou-se um instrumento em que os mesmos foram solicitados a discorrer a respeito da relevância de abordar a temática dos agrotóxicos na Educação Básica. A análise apontou a necessidade de entender a temática dos agrotóxicos em aspectos amplos que correspondem às dimensões teórico-metodológicas e conceituais, bem como econômicas, sociais, culturais, ambientais e éticas.

This work aims to analyze and discuss the students' understandings of undergraduate course in Field Education of the Federal University of Santa Catarina (UFSC) on the thematic of pesticides in science teaching. To grasp the understandings of students it was applied an instrument in which the undergraduates were asked to writer about the importance of addressing the issue of pesticide in basic education. The analysis pointed out the need to understand the thematic of pesticides on broad aspects that corresponds conceptual contents from the area of Natural Science and Mathematics, as well as social, environmental, political, economics, ethnical and others aspects.

A resistência do solo à penetração (RP) e a densidade do solo (Ds), entre outros atributos indicadores da qualidade física do solo, vêm sendo determinadas na mesma amostra indeformada de solo. O objetivo deste trabalho foi avaliar, em dois solos com diferentes teores da fração argila, a influência da determinação da RP sobre os valores da Ds, quando os dois atributos são estimados na mesma amostra indeformada. As amostras indeformadas de solo foram coletadas nas camadas 0,00-0,10 e 0,10-0,20 m, em duas áreas experimentais com classes texturais distintas, textura argilosa e textura muito argilosa. Em cada camada, retiraram-se 120 amostras de solo com anéis volumétricos, totalizando 240 amostras. Desses 120 anéis volumétricos coletados em cada camada, separaram-se dois conjuntos de 60 unidades. Um conjunto foi utilizado para determinar a RP e Ds na mesma amostra indeformada, sendo denominado como “amostras perfuradas”. Outro conjunto foi usado para determinar exclusivamente a Ds, sendo denominado como “amostras intactas”. Nas comparações dos valores de Ds entre as amostras perfuradas e as intactas, procedeu-se a análise de variância seguindo delineamento inteiramente casualizado. A comparação de médias foi realizada por meio do teste t a 5 %. Os valores da Ds com textura argilosa, determinados nas amostras perfuradas, foram semelhantes aos da Ds, definidos nas amostras intactas nas duas camadas avaliadas. Entretanto, no solo com textura muito argilosa, observou-se nas duas camadas avaliadas que os valores da Ds foram menores nas amostras perfuradas do que os determinados nas amostras intactas. Portanto, concluiu-se que a avaliação da RP e Ds na mesma amostra indeformada pode ser realizada em solos com textura argilosa, mas, em solos com textura muito argilosa, a determinação de ambos os atributos deve ser realizada em amostras distintas.

Soil quality indicators such as penetration resistance (PR) and bulk density (BD) are traditionally determined in a single undisturbed soil sample. The aim of this study was to assess the effect of PR measurements of undisturbed samples on the determination of BD in the same sample of two soils differing in clay contents. To this end, samples were collected from the 0.00-0.10 and 0.10-0.20 m layers of two soils of clayey and very clayey texture. Volumetric rings were used to collect a total of 120 undisturbed soil samples from each soil layer that were divided into two subsets containing 60 units each. One sample set, designated “perforated samples”, was used to determine PR and BD in the same undisturbed sample; the other, named “intact samples”, was used to determine BD only. Bulk density values for perforated and intact samples were compared by analysis of variance, using a completely randomized experimental design. Means were compared by the t-test at 5 %. The BD values for the clayey soil were similar in perforated and intact samples from the two layers. However, BD of the very clayey soil was lower in the perforated than in the intact samples at both depths. Therefore, PR and BD in clayey soils can be accurately determined in the same undisturbed sample whereas in very clayey soils, different samples are required for this purpose.