Aim To determine new energy parameters in micro-CT to allow appropriate segmentation of dental cementum from the surrounding structures. Methods For this pilot study, 11 single-rooted premolar teeth of young subjects aged 12 to 21 were selected. The teeth were scanned using high-energy microtomography (SkyScan 1173, Bruker) with varying acquisition energies (60, 70, and 80 kV). Each tooth was scanned three times. The images were reconstructed and analyzed by calculating the volume (mm3) of dental cementum in the cervical, middle, and apical root thirds among the different scanned stacks. The mean cementum volume in the root thirds was obtained, and correlated with the patient’s age, using Pearson’s correlation. Results The mean age of the patients in the sample was 16,73 years. For the 60kV energy, the cementum volumes were 1.01 mm3, 1.00 mm3, and 0.58 mm3, for the cervical, middle, and apical thirds, respectively. For 70kV, it was 1.08 mm3, 1.20 mm3, and 0.71 mm3 for the respective thirds. And for 80kV,0.55 mm3, 0.91 mm3, and 0.67 mm3 for the respective thirds. Conclusion An acquisition energy of 70kV resulted in the best segmentation and reproducibility of the results. Micro-CT can be a useful tool to non-destructively evaluate the dental cementum. microCT micro CT structures study 1 singlerooted single rooted 2 selected highenergy high SkyScan 1173 Bruker 60, 60 (60 70 8 kV. kV . kV) times mm (mm3 cervical middle stacks obtained patient s Pearsons Pearson correlation 1673 16 73 16,7 years 101 01 1.0 100 00 058 0 58 0.5 respectively 108 08 120 20 1.2 071 71 0.7 80kV055 80kV 55 80kV,0.5 091 91 0.9 067 67 0.6 results MicroCT Micro nondestructively non destructively 117 6 (6 7 (mm 167 16, 10 1. 05 5 0. 07 80kV05 80kV,0. 09 9 06 ( 80kV0 80kV,0 80kV,

ABSTRACT Reduced stability and structural resilience expose sandy soils to physical degradation under intensive production systems. This study aimed to evaluate the influence of different cover crops (CC) under no-tillage system (NTS) cotton cropping, grown either individually or in combination, on the soil physical quality (SPQ) of a sandy loam Oxisol (Latossolo) in southeastern Brazil. To quantify the effects of CC on soil physical quality indicators, an experiment in randomized blocks design was implemented with the treatments: CC1: single cultivation of Ruzi grass; CC2: Intercropping of Pearl Millet + Ruzigrass; CC3: Intercropping of Pearl Millet + Velvet bean; CCMixture: Intercropping of Ruzi grass, Pearl Millet and Velvet bean; and Control: maintenance of spontaneous plants. Undisturbed samples were taken from layers 0.00-0.10, 0.10-0.20, 0.20-0.40 and 0.40-0.60 m, in which were determined the soil bulk density (Bd), total porosity (TP), available water (AW), soil penetration resistance (PR) and the least limiting water range (LLWR). According to the multivariate analyses, the CC2 treatment resulted in better SPQ compared to the other treatments. The LLWR, air-filled porosity (θAFP), and AW were responsible for differentiating the CC2 treatment compared to the other treatments evaluated. Regardless of treatments, values of Bd> 1.75 Mg m-3 result in loss of SPQ due to the significant increase in PR and decreases in AW and LLWR. In the CC3 and Control, there was a physical impediment caused by the increase in Bd in the 0.10-0.20 m layer, which could result in the confinement of cotton roots to the surface, making them more susceptible to water stress. Soil PR reached values greater than 2.5 MPa for water contents lower than the θPWP in most treatments. In treatment CC3, for water contents equivalent to the θPWP, the PR did not exceed 6 MPa, while for the other treatments, the PR reached values greater than 10 MPa. Only the PR was influenced using CC. Soil moisture is considered crucial to maintain PR below impeding values, determining the control of the physical quality of this sandy soil. systems (CC notillage no tillage NTS (NTS cropping combination (SPQ Latossolo (Latossolo Brazil indicators CC1 grass Ruzigrass bean CCMixture Control plants 0.000.10, 000010 0.00 0.10, 0 00 0.00-0.10 0.100.20, 010020 0.10 0.20, 20 0.200.40 020040 0.20 0.40 40 0.20-0.4 0.400.60 040060 0.60 60 0.40-0.6 Bd, , (Bd) TP, TP (TP) AW, (AW) (PR LLWR . (LLWR) analyses airfilled air filled θAFP, θAFP (θAFP) evaluated 175 1 75 1.7 m3 3 m- 0.100.20 0.10-0.2 layer surface stress 25 2 5 2. 000 0.000.10 00001 0.0 010 0.00-0.1 100 01002 0.1 020 200 0.200.4 02004 0.2 040 0.4 4 0.20-0. 400 0.400.6 04006 060 0.6 0.40-0. (Bd (TP (AW (LLWR (θAFP 17 7 1. 0.100.2 0.10-0. 0.000.1 0000 0. 01 0.00-0. 0100 02 0.200. 0200 04 0.20-0 0.400. 0400 06 0.40-0 0.100. 0.10-0 0.000. 0.00-0 0.200 0.20- 0.400 0.40- 0.100 0.10- 0.000 0.00-

ABSTRACT The objective of this work was to verify the effect of different management systems on the physical-hydric quality of a Vertisol located in the climatic domain of the Brazilian Semiarid. The treatments were composed by the following management systems: (S1) Pasture (Cynodon spp.) With 4 years; (S2) Pomegranate (Punicata granatum L.) aged 6; (S3) Forage sorghum (Sorghum bicolor L.) aged 4 years and (S4) native vegetation. The soil water retention curve, soil density, porosity of soil (macro, microporosity and, total porosity), soil aeration capacity and free air porosity. The data were analyzed using multivariate statistics. The results demonstrate that the Vertisol presents high retention and low availability of water to the plants. Better structural quality was observed in the soil under native forest. It is concluded that the management systems composed of pasture and sorghum are promoting negative changes to the soil structure, with a reduction of macroporosity and of the aeration capacity of the soil.

RESUMO O objetivo deste trabalho foi verificar o efeito de diferentes sistemas de manejo sobre a qualidade físico-hídrica de um Vertissolo localizado no domínio climático do Semiárido brasileiro. Os tratamentos foram compostos pelos seguintes sistemas de manejo: (S1) Pastagem (Cynodon spp.) com 4 anos; (S2) Romã (Punicata granatum L.) com 6 anos;(S3) Sorgo forrageiro (Sorghum bicolor L.) com 4 anos e, (S4) vegetação nativa. Avaliou-se a retenção de água no solo por meio da curva característica de umidade, densidade do solo, porosidade do solo (macro e microporosidade e porosidade total), capacidade de aeração do solo e porosidade livre de ar. Os dados foram analisados através da estatística multivariada. Os resultados demonstram que o Vertissolo apresenta elevada retenção e baixa disponibilidade de água as plantas. Melhor qualidade estrutural foi observada no solo sob mata nativa. Conclui-se que os sistemas de manejo composto por pastagem e sorgo estão promovendo mudanças, até o presente momento de forma negativa à estrutura do solo, com redução da macroporosidade e da capacidade de aeração do solo.

ABSTRACT The soils of the Brazilian semi-arid are under a constant process of degradation and sustainable agricultural production strategies must be adopted in order to alleviate this problem. Therefore, the objective of this work was to evaluate the physical-water behavior of an Albaqualfs four years after the implantation of crop-livestock-forest integration systems in the Brazilian semiarid. The experiment was installed in the county of Alagoinha, PB, in an Albaqualfs with a sandy-loam texture. Five integration systems in randomized block design (DBC) with four replications were evaluated: i) Purple Ipe (Tabebuia impetiginosa) + Brachiaria decumbens (iPF1); ii) Gliricidia (Gliricidia sepium) + Urochloa decumbens (iPF2); iii) Sabiá (Mimosa caesalpiniifolia) + Urochloa decumbens (iPF3); iv) Maize (Zea mays) + Urochloa decumbens (iLP); v) Urochloa decumbens (pasture). The data submitted to analysis of variance and Tukey's test (p<0.05) demonstrated that the crop-livestock-forest integrated system, after the period of four years, has not yet promoted significant physical improvement of the attributes of the Albaqualfs under study, however, an attribute such as the S index, presented satisfactory values. Regarding the condition prior to the implantation of the systems, there is a positive change in the structure, reflecting in the reduction of the bulk density of the soil and an increase in the total porosity.

RESUMO Os solos do semiárido brasileiro estão sob um constante processo de degradação e estratégias sustentáveis de produção agropecuária devem ser adotadas de forma a mitigar este problema. Sendo assim, o objetivo deste trabalho foi avaliar o comportamento físico-hídrico do solo quatro anos após a implantação de sistemas de integração lavoura-pecuária-floresta no semiárido Brasileiro. O experimento foi instalado no município de Alagoinha, PB, em um Planossolo Háplico de textura franco-arenosa. Foram avaliados cinco sistemas de integração em delineamento de blocos ao acaso (DBC) com quatro repetições: i) Ipê roxo (Tabebuia impetiginosa) + Urochloa decumbens (iPF1); ii) Gliricídia (Gliricidia sepium) + Urochloa decumbens (iPF2); iii) Sabiá (Mimosa caesalpiniifolia) + Urochloa decumbens (iPF3); iv) Milho (Zea mays) + Urochloa decumbens (iLP); v) Urochloa decumbens (Pastagem). Os dados submetidos a análise de variância e teste de Tukey (p<0,05) demonstraram que a integração Lavoura-Pecuária-Floresta, após o período de quatro anos, ainda não promoveu melhoria física significativa dos atributos físicos do Planossolo em estudo, porém, o índice S apresentou valores satisfatórios. Em relação a condição antecedente a implantação dos sistemas, verifica-se uma alteração positiva na estrutura, refletindo na redução da densidade do solo e aumento da porosidade total.