63 research outputs found

    Geo-environmental mapping using physiographic analysis: constraints on the evaluation of land instability and groundwater pollution hazards in the Metropolitan District of Campinas, Brazil

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    Geo-environmental terrain assessments and territorial zoning are useful tools for the formulation and implementation of environmental management instruments (including policy-making, planning, and enforcement of statutory regulations). They usually involve a set of procedures and techniques for delimitation, characterisation and classification of terrain units. However, terrain assessments and zoning exercises are often costly and time-consuming, particularly when encompassing large areas, which in many cases prevent local agencies in developing countries from properly benefiting from such assessments. In the present paper, a low-cost technique based on the analysis of texture of satellite imagery was used for delimitation of terrain units. The delimited units were further analysed in two test areas situated in Southeast Brazil to provide estimates of land instability and the vulnerability of groundwater to pollution hazards. The implementation incorporated procedures for inferring the influences and potential implications of tectonic fractures and other discontinuities on ground behaviour and local groundwater flow. Terrain attributes such as degree of fracturing, bedrock lithology and weathered materials were explored as indicators of ground properties. The paper also discusses constraints on- and limitations of- the approaches taken

    An Overview of Polymeric Hydrogel Applications for Sustainable Agriculture.

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    Abstract: Agriculture, a vital element of human survival, confronts challenges of meeting rising demand due to population growth and product availability in developing nations. Reliance on pesticides and fertilizers strains natural resources, leading to soil degradation and water scarcity. Addressing these issues necessitates enhancing water efficiency in agriculture. Polymeric hydrogels, with their unique water retention and nutrient-release capabilities, offer promising solutions. These superabsorbent materials form three-dimensional networks retaining substantial amounts of water. Their physicochemical properties suit various applications, including agriculture. Production involves methods like bulk, solution, and suspension polymerization, with cross-linking, essential for hydrogels, achieved through physical or chemical means, each with different advantages. Grafting techniques incorporate functional groups into matrices, while radiation synthesis offers purity and reduced toxicity. Hydrogels provide versatile solutions to tackle water scarcity and soil degradation in agriculture. Recent research explores hydrogel formulations for optimal agricultural performance, enhancing soil water retention and plant growth. This review aims to offer a comprehensive overview of hydrogel technologies as adaptable solutions addressing water scarcity and soil degradation challenges in agriculture, with ongoing research refining hydrogel formulations for optimal agricultural use

    Exploring the perception of orthodontic treatment need using the dental aesthetic index and index of orthodontic treatment need

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    Introduction: This study aimed to explore the perception of orthodontic treatment need by using the Dental Aesthetic Index (DAI) and the Index of Orthodontic Treatment Need (IOTN). Methods: A cross-sectional study was conducted on a representative random sample (N = 248) of adolescents aged 12 years. The DAI and both components of IOTN were used to evaluate malocclusion. The association between the Dental Health Component of the IOTN with gender and ethnic group were analyzed by chi-square test. The concordances between the indexes were analyzed by the kappa statistic, with 95% confidence intervals (Cis). Results: The prevalence of adolescents with high severity and orthodontic treatment need was 10.5% (95% CI, 6.7-14.3), 36.5% (95% CI, 32.3-44.3), and 73.4% (95% CI, 67.9-78.9) for the Aesthetic Component of the IOTN, Dental Health Component of the IOTN, and DAI, respectively. The indexes showed high agreement for the cases with low treatment need, whereas low concordance was observed for the cases with high treatment need. Conclusion: The perception of orthodontic treatment need was assessed differently using DAI and IOTN156681882
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