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  1. Home
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Browsing by Issue Date, starting with "2021-07-26"

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    Propriedades citotóxicas de complexos de Cu(I)-Trifenilfosfina com ligantes aciltioureias ou naftoquinonas
    (Universidade Federal de São Carlos, 2021-07-26)
    Leite, Celisnolia Morais
    ;
    Batista, Alzir Azevedo
    ;
    https://lattes.cnpq.br/6469642481998660
    ;
    https://lattes.cnpq.br/9638881050186865
    In this work, the synthesis, characterization, and evaluation of the cytotoxic activity of sixteen Cu(I)/Triphenylphosphine complexes containing the acylthiourea or naphthoquinones ligands are presented. The complexes were divided into two series based on the classes of the ligands used. The first series is composed of the neutral complexes of general formula [Cu(Ln)(PPh3)2] (1-6) and monocationic complexes of general formula [Cu(Ln)(PPh3)2]NO3 (1a 6a), where Ln= acylthiourea and PPh3= triphenylphosphine. The second series is composed of the neutral complexes of general formula [Cu(NQn)(PPh3)2] (1b 4b), where NQn= naphthoquinone and PPh3= triphenylphosphine. All complexes were characterized by different techniques such as elemental analysis, molar conductivity, infrared absorption spectroscopy, 1D and 2D nuclear magnetic resonance (31P{1H}, 1H and 13C{1H}), mass spectrometry, and X-ray diffraction. In the 13C{1H} NMR spectra, the complexes (1-6) stood out by showing the unusual chemical shift pattern, for the C=O and C=S carbon atoms of the acylthiourea ligand after bidentate (S, O) and anionic coordination. The experimental results were supported by DFT studies that suggested that relativistic effects strongly influenced the NMR protection constants of the light atoms due to coordination to the heavy atom Cu. The stability of the complexes in the cell culture medium was investigated and all the complexes were shown to be unstable, directly influencing the biological results obtained. The in vitro cytotoxicity of the complexes was determined in the breast (MCF7 and MDA MB-231) and lung (A549) tumor cell lines and in the corresponding non-tumor breast (MCF-10A) and lung (MRC-5) cell lines, and all complexes were actives exhibiting IC50 values in the same range in different cell lines. The compounds were more active than the free ligands and the precursor salt of the complexes in different cell lines, showing that even unstable complexes are relevant for the cytotoxic action. In general, the acylthiourea series complexes, 1 and 1a, were able to change the morphology of MDA-MB-231 cells, inhibit colony formation, showing cytotoxic and cytostatic effects on this cell line, significantly altering the cytoskeleton of cells, reducing the density, and promoting the condensation of the F-actin filaments. They promoted the increase of cells in the fragmented DNA region (sub-G0) and induced cell death by apoptosis. The complexes of the naphthoquinone series, 1b, and 4b, altered the morphology of MDA-MB-231 cells, inhibited colony formation at concentrations higher than the IC50, and were able to inhibit cell migration. Finally, the compounds synthesized and characterized in this work are relevant reports of copper (I) complexes with cytotoxic properties in different tumor cell lines with potential for future studies in vivo models.
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    Innovation ecosystems and strategy in the COVID-19 crisis
    (Universidade Federal de São Carlos, 2021-07-26)
    Oliveira, Wesley da Paixão de
    ;
    Guimarães, Márcia Regina Neves
    ;
    https://lattes.cnpq.br/9250214706491925
    ;
    Silva, João Eduardo Azevedo Ramos da
    ;
    https://lattes.cnpq.br/3823047207711289
    The COVID-19 pandemic is a disturbance that forced enterprises to rethink their strategies and ecosystems to keep running. Nevertheless, there is a lack of prior register to show the best policies to adopt in such circumstances. Hence, researchers and practitioners must comprehend how companies are responding to this unprecedented health crisis. Furthermore, it is of equal importance to comprehend the pandemic consequences on ventures’ strategies and ecosystems. In this sense, the research identified how four ventures handled such a situation. Through a multiple and holistic case study, supported by exploratory and qualitative approaches, the research provided a detailed description of their competitive strategies, innovation ecosystems, and the adopted measures against the crisis. The main findings were as follows: (i) The pandemic affected the studied ventures and ecosystems at different levels. The crisis severely hit the approached enterprises and ecosystems from the event and consultancy industries, especially the former. For example, the former entirely ceased their activities for a while, impacting the ecosystem activity flow. However, the pandemic boosted the businesses of the organizations and ecosystems from the telehealth and medication industries. For example, the medication case showed no change in its ecosystem composition and further capitalized from new projects that emerged due to the COVID-19 disruption. (ii) The ventures proposed changes related to the value proposition, interaction process, and activities and information flow across the ecosystem to keep running. For example, those severely affected by the COVID-19 succeeded in delivering their solutions entirely online (the consultancy industry case) or avoiding crowds (the event industry case). Further, those less affected benefited by adopting work from home (the medication industry case) or serving occupational health and safety care entirely online (the telehealth industry case). (iii) The enterprises employed these modifications mainly by adopting (the medication and telehealth industries cases) or increasing (the event and consultancy industries cases) digital solutions internally and crosswise the ecosystems. Therefore, the studied cases' competitive strategy and innovation ecosystems goals have not changed due to the pandemic: what changed was the means to achieve these objectives to respond to the crisis and keep moving forward.
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    Co-cristalização da curcumina com d-manitol: caracterização e aplicações sobre larvas do Aedes aegypti (Linnaeus, 1762)
    (Universidade Federal de São Carlos, 2021-07-27)
    Garbuio, Matheus
    ;
    Inada, Natalia Mayumi
    ;
    https://lattes.cnpq.br/3595196074265255
    ;
    Bagnato, Vanderlei Salvador
    ;
    https://lattes.cnpq.br/4947860249518663
    The search for new compounds to eliminate Aedes aegypti mosquito larvae is a strategy used by several researchers. Brazil, for example, has been facing major problems due to the high number of cases of arboviruses transmitted by the mosquito. In order to reduce the speed of selection of populations resistant to chemical insecticides, photodynamic inactivation (IFD) in Ae. aegypti has been used as an alternative. Curcumin (CUR), a pigment extracted from the roots of Curcuma longa has been discovered as a potential photolarvicide. Despite advances in this area, CUR still has some limitations, such as its low stability, bioavailability and water solubility. Thus, the objective of this study was to develop formulations based on CUR and D-mannitol via co-crystallization, in order to obtain an improvement in their solubility and, consequently, enable their application in Ae. aegypti. The characterization of the formulations carried out: absorption spectroscopy (UV-vis), infrared spectroscopy (FTIR), fluorescence spectroscopy, confocal microscopy, solubility tests at pH 2, 7 and 11, the degradation test (of the most effective formulation) in fluorescent lamps (0.5 mW/cm²) 24h. For efficacy trials, the formulations were used at concentrations between 0.00625; 0.0125; 0.025; 0.05; 0.1; 0.2; 0.4; 0.8 mg.L-1 with 18W white fluorescent lamps, 0.5 mW/cm2 irradiance and after 24h larvae mortality were recorded. The determination of the internalization and elimination time of the formulations in the digestive system of Ae. aegypti through optical microscope images. Acute toxicity tests and simulated field application (of the most effective formulation) were carried out. And the analysis of microbiota activity in artificial breeding waters and in the simulated field where the formulations were placed by counting the log of colony forming units. Among the formulations, formulation 1 had the best solubility, followed by 2, 3 and 4, however, in relation to photolarvicidal efficacy, formulation 3 had the best performance, with a LC50 value of 0. 01 mg.L-1, in addition, had the shortest internalization time and the longest elimination time, 30 minutes and 8 days, respectively. With its best results, formulation 3 was chosen as the most effective, in addition to presenting an environmental safety, as it does not present mortality in acute ecotoxicity tests and maintains its persistence in the field for 14 days in light and 6 days in the shade.
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    Treino funcional de alcance e controle de tronco em lactentes pré-termo moderados a tardios: ensaio clínico randomizado e controlado
    (Universidade Federal de São Carlos, 2021-07-27)
    Sato, Natália Tiemi da Silva
    ;
    Cunha, Andrea Baraldi
    ;
    https://lattes.cnpq.br/8413239950848240
    ;
    Tudella, Eloisa
    ;
    https://lattes.cnpq.br/3207258034860219
    Introduction: Moderate to late preterm infants may present delays on the onset and development of those abilities due to possible complications of prematurity. Studies on specific abilities such as reaching and positioning experiences have shown a positive effect to optimize the reaching performance, head control and motor development in full-term and preterm infants. However, due to the relationship between manual abilities and trunk control, it is relevant to develop an intervention that emphasizes on the positioning experiences and reaching to enhance the motor development of infants at biological risk. Objective: to verify the feasibility and effect of early intervention programs on gross motor performance, trunk control and reaching performance in moderate to late preterm infants in reaching emergence. Methods: Preterm infants at the onset of reaching ability (Mean=4.36, SD=0.54 months) were randomized assigned into two groups: Functional Reaching and Trunk Control Training (experimental group-EG) and Positioning social training (control group-GC). Infants were assessed into 4 visits: 1) pre-test; 2) post-intervention 1; 3) post-intervention 2, and 4) follow-up. All assessments were performed by a blinded evaluator. The Functional Reaching and Trunk Control Training, consisting of functional activities was performed by a pediatric physical therapy and parents at home. The Positioning social training, consisting of only static positioning experiences, was performed only by parents. Parents used a daily log for both trainings (dose, frequency, duration and infant’s behavior), and responded to a parent feedback questionnaire. For the feasibility variables of early intervention programs, t-test for independent samples and the Chi-Square test were performed. For gross motor performance, the Mann-Whitney test was applied. For the segmental trunk control, the Chi-Square test was applied, and for trunk and reaching kinematics variables, the mixed linear model was used. Results: there were no differences of feasibility outcome measures for both intervention programs. Parents provide a positive feedback about both programs. At the follow-up, the EG presented higher total gross motor score than CG. Both groups improved on motor performance across time. There were no significant differences between groups in the segmental trunk control, trunk and reaching performance, but there were substantively important effects (clinically relevant). After training and at follow-up, EG infants presented higher trunk movement and smoother and faster reaching than CG. Conclusion: Both early intervention programs were considered feasible and both groups showed improvement on gross motor performance, trunk control and reaching performance across time. Substantively important effects were found, favoring Functional Reaching and Trunk Control Training, which can be an efficient early intervention strategy for clinicians.
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    Evolução microestrutural e propriedades mecânicas das ligas Al-10%Si-0,45%Mg e Al-10%Si-1,0%Mg
    (Universidade Federal de São Carlos, 2021-07-28)
    Gandolfi, Maressa
    ;
    Spinelli, José Eduardo
    ;
    https://lattes.cnpq.br/8882038118634925
    ;
    https://lattes.cnpq.br/3579243272425225
    Al-Si alloys with high silicon (Si) content are widely used in aerospace, automotive, microelectronics, among others. In this context, the Al-10 wt.% Si alloys with the addition of Magnesium (Mg) are alternatives that arouse interest for processing in permanent molds, by lost wax, by high pressure die-casting and by additive manufacturing. Due to growing interest, there are necessary more in-depth studies of the interrelationships between solidification thermal parameters, microstructural parameters and mechanical properties of the Al-10 wt. % Si-Mg alloys, both due to the scarcity of these data in the literature and due to the importance of this knowledge in the pre-programming related to foundry processes. In this sense, a study for the conditions of slow and moderate solidification was carried out through this Master's proposal. Through transient directional solidification experiments a wide range of dendritic scale variation was obtained for both Al-10 wt.% Si-0.45 wt.% Mg and Al-10 wt.% Si-1.0 wt.% Mg alloys, with primary and secondary dendritic spacings, 1 and 2 ranging from 76 m to 360 m and from 17 m to 38 m, respectively. The interdendritic phases detected were Mg2Si with Chinese Script morphology and Si with lamellar morphology, with a higher fraction of Mg2Si for the alloy containing 1.0 wt.% Mg. Thanks to the higher fraction of refined Mg2Si particles, in addition to greater refining and complexity of the dendritic network (smaller 2), the Al-10 wt.% Si-1.0 wt.% Mg alloy achieved greater mechanical strength and ductility compared to the Al-10 wt.% Si-0.45 wt.% Mg alloys. The samples of the Al-10 wt.% Si-1.0 wt.% Mg alloy with 2 of 16 m show the best balance of tensile properties with ultimate tensile strength limit of 220 MPa, yield tensile strength of 142 MPa and elongation-to-fracture of 5%.
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    Cultura e Interculturalidade em movimento no ensino de Português Língua Estrangeira: um estudo bibliográfico-documental
    (Universidade Federal de São Carlos, 2021-07-28)
    Yonaha, Tábata Quintana
    ;
    Viana, Nelson
    ;
    https://lattes.cnpq.br/6252579012192711
    ;
    https://lattes.cnpq.br/4076862793928173
    This dissertation is the result of a qualitative bibliographic research design. The concepts of culture and interculturality in the Foreign Language Teaching (henceforth FLT) are investigated under the scope of Applied Linguistics. Its main aim was to gather theoretical contributions on these concepts, to relate and discuss them from a critical perspective following an interpretative-constructivist approach. The reference sources for the development of this research were primary (books, articles, technical texts) and tertiary (databases). We present primary concepts about culture in the language studies area (KRAMSCH, 2011; 2017). In addition, we develop a historical overview of the relationship between language and culture based on the works of Risager (1998) and Kramsch (2001; 2006; 2007; 2010; 2011). Another concept presented is culture under different perspectives based on the contributions of Holliday (2012) and Abdallah-Pretceille (2006). This work discusses the most widely used intercultural models in academic research on this theme (BYRAM, 1998; BENNETT, 1998; DEARDORFF, 2009) through analyzing their main characteristics. The in-depth analysis of these models has the emergency of an epistemic turn of popular knowledge and scientific knowledge supported and advocated in Walsh's decolonial proposals (2008; 2010). Issues as power, exclusion, subordination of identities, knowledge, languages and systems are scrutinized in Walsh’s work, as well as in the works of Dervin (2006; 2017). The author problematizes solid conceptions of culture and interculturality while taking the critical interculturality proposals of Tubino (2005) and Candau (2016) into consideration. Seeking, with this discussion, to contribute to the visibility and expansion of this theme in the teaching of Portuguese as a Foreign Language (PFL), we focused on the Celpe-Bras exam due to its washback effects into this field, analyzing guiding documents for the face-to-face interaction of the evaluation process, namely in relation to the notions of culture and interculturality embodied in aspects of the Provocative Elements and Interaction Scripts. We consider that the results of this research can contribute to discussions and, potentially, to the practices of PFL teachers, in initial and in continuous professional development, in a reflexive way, since the pedagogical alternatives presented emphasize the importance of breaking away from solid constructions of culture ( DERVIN; MACHART, 2015) and to question crystallized senses and debatable certainties of knowledge (MOITA LOPES; FABRÍCIO, 2015) about cultures and interculturality in the context of teaching in this area.
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    Uso de extrato de canela, extrato de cravo e hipoclorito de sódio no controle de Fusarium oxysporum f. sp. lycopersici e Alternaria alternata
    (Universidade Federal de São Carlos, 2021-07-28)
    Carmello, Camila Rodrigues
    ;
    Rosa-Magri, Marcia Maria
    ;
    https://lattes.cnpq.br/4166319985147604
    ;
    Cardoso, Jean Carlos
    ;
    https://lattes.cnpq.br/3681181863704059
    The tomato crop is very sensitive to phytosanitary problems, among the fungal diseases that affect the crop, the Fusarium wilt caused by Fusarium oxysporum f. sp. lycopersici and the black spot, caused by Alternaria alternata. The use of pesticides is one of the main ways to manage pests and diseases in tomato crops, making control measures based on systematic applications of fungicides following a calendar of weekly applications. While the application of fungicides brings benefits to the productivity of horticultural crops, their use has been restricted by environmental risks and the greater demand for food without the presence of residues of these substances. In this context, the use of natural products from plants and already used as food can be an alternative form of control. Thus, this work aims to evaluate the in vitro growth inhibition potential of different pathogenic races of Fusarium oxysporum f. sp. lycopersici (causer of fusarium wilt) and Alternaria alternata (black spot), by the use of aqueous extract of cinnamon and aqueous extract of clove, in addition to the use of sodium hypochlorite solution, as well as its application to reduce symptoms of black pinta on tomato fruits in post-harvest. For this purpose, the work was divided into two chapters, where in vitro tests were performed in the first chapter to observe the potential of the aqueous extract of cinnamon and sodium hypochlorite in the control of Alternaria alternata and the three main races of Fusarium oxysporum f. sp. Lycopersici. In the second chapter, the effects of the aqueous extract of cinnamon and the aqueous extract of clove on the control of Alternaria alternata in vitro and post-harvest of tomatoes were treated. Complete growth inhibition of the three races of Fusarium oxysporum f. sp. lycopersici and Alternaria Alternata only when using sodium hypochlorite from a concentration of 3%, and a partial inhibition with the use of cinnamon extract. Both, cinnamon extract and sodium hypochlorite solution, at concentrations above 2%, reduced IVCM values. Total inhibition of Alternaria mycelial growth under in vitro conditions was obtained using 5% clove extract. The combination of cinnamon and clove, both at 2.5 and 5%, also enabled complete inhibition of mycelial growth. In addition to the effect on mycelial growth, it was also possible to verify the inhibition of spore germination and control of the fungus in the post-harvest of tomato fruits.
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    Análise clínica comparativa da terapia sinérgica de ultrassom e laser e terapias isoladas para tratamento da fibromialgia
    (Universidade Federal de São Carlos, 2021-07-29)
    Bruno, Juliana da Silva Amaral
    ;
    Aquino Junior, Antonio Eduardo de
    ;
    https://lattes.cnpq.br/8720193315570177
    ;
    Bagnato, Vanderlei Salvador
    ;
    https://lattes.cnpq.br/4947860249518663
    Fibromyalgia is a diffuse and chronic musculoskeletal pain syndrome that affects mainly women. In Brazil, it is present in 2.5% of the population and, in addition to the generalized painful sensation, other disorders are associated with non-restorative sleep, fatigue, cognitive changes, anxiety and depression, among others. Today, there are no specific exams for diagnosis due to lack of knowledge of its etiology, treatments are guided by symptoms. Treatments can be pharmacological and/or non-pharmacological. However, physiotherapy is present in the area of health sciences to reduce painful and inflammatory episodes and to recover and maintain physical integrity. The use of equipment such as therapeutic ultrasound is the most used resource in physical therapy for inflammatory disorders of the musculoskeletal system. Another piece of equipment, which has been gaining attention in rehabilitation, is the low-intensity laser, which has multiple effects and indications in a punctual and even systemic way. In this sense, a researcher from the IFSC / USP joined together as two treatment techniques in a single equipment, offering patients a synergistic ultrasound and laser therapy. With the technological advance of the device and analyzing the study by Albrecht et al (2013), which identified the increase in nerve endings around blood vessels in the palms of the hands, specifically in the hypothenar region, it was what motivated us to start the study with fibromyalgia patients applying the treatment on the palms of the hands. Thus, the aim of this study was to analyze the effects on pain, quality of life and sleep quality, depression, anxiety and physical activity in these patients, separating the study into three treatment groups: Laser Group, Ultrasound Group and Ultrasound + Laser Group, being taken in the immediate pre- and post-treatment, and 30 days after the end of the treatment. The application was carried out with the prototype that allows the use only of laser or ultrasound, or combining the two techniques. The intervention protocol was carried out with 10 sessions in total, at a frequency of 3 times a week on alternate days, and the application time was 3 minutes in each palm, in all groups. The results exceeded expectations. The isolated therapy groups, laser and ultrasound, had similar results, less than 70%, in the immediate post-treatment, but the group that received synergistic therapy had a result of 92.32% in pain reduction. Quality of life in the synergistic therapy group optimized 72.37% and isolated therapies below 59%. Thus, the Ultrasound + Laser Group, 30 days after the end of treatment, showed 100% and 98.23% efficacy of the final results, in relation to pain and quality of life, respectively. It is concluded that the synergistic effect of ultrasound and laser on the palms of patients with fibromyalgia have satisfactory results corresponding to improvement in pain and quality of life in the immediate and medium-term post-treatment. Furthermore, these results directly influence the reduction of anxiety and depression, and consequently, improve the quality of sleep and the ability to perform physical activity.
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    Comparação do perfil de metabólitos secundários de cultivares de soja
    (Universidade Federal de São Carlos, 2021-07-29)
    Arroyo, Victoria Patricia Pena
    ;
    Wouters, Felipe Christoff
    ;
    https://lattes.cnpq.br/4392349445398645
    ;
    https://lattes.cnpq.br/9409311086029770
    Soybean (Glycine max) is one of the most important crops in the world socioeconomic scenario, especially in Brazil. However, this crop is constantly attacked by different pests. Plant resistance against herbivores occurs partially through the production of secondary metabolites such as flavonoids. Wild soybeans and cultivated varieties exhibit different levels of resistance to agricultural pests, which may be a consequence of the variability in their secondary metabolite profiles. Thus, identifying these substances among different genotypes and understanding their role in the insect-plant interaction mechanisms is important for a more comprehensive and reliable characterization of soybean resistance. This work proposes to compare the profile of secondary metabolites between 4 cultivated soybean varieties resistant (PI 229358 and IAC 100) and susceptible (BRS 257 and IAC PL-1) to pests and a wild soybean variety (PI 407270). The chemical profile of young and old leaves in the V3 development stage was analyzed. Plants were grown in a greenhouse and different samples were extracted and analyzed by LC-MS. The analysis of the flavonoid profile in the 5 varieties allowed the identification of 18 isoflavone conjugates (daidzein, genistein and glycitein), some of which were present in greater abundance in old leaves. 39 flavonols were also detected, including kaempferol and quercetin conjugates; accumulated mostly in young leaves. Furthermore, it was shown that wild soybeans have higher levels of flavonoids in their younger leaves, in contrast to cultivated varieties. This information will allow us to understand the dynamics of flavonoids in the insect-plant interaction mechanisms and contribute to the creation of resistant varieties and new targets for the management of agricultural pests, contributing to the sustainable development of agriculture.
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    Ao internacional e além: as relações de poder-saber na constituição da identidade transnacional brasileira inscritas em livros didáticos de Português para estrangeiros
    (Universidade Federal de São Carlos, 2021-07-29)
    Cardoso, Jorcemara Matos
    ;
    Baronas, Roberto Leiser
    ;
    https://lattes.cnpq.br/4613001301744682
    ;
    https://lattes.cnpq.br/3583449810396955
    Over the decades, numerous events were inaugurated in the Brazilian diplomacy device (BDD). A whole semiotic was built on top of it, which started organizing how people see and talk about Brazil abroad and within the country itself. However, from the beginning of the 1990s onwards, the ideals of the New Republic designed in the 1988 Brazilian constitution started to go through the construction of policies and institutions that bring to the public debate problematic issues intensely debated by civil society movements. On the sidelines of official state discourses for centuries. This progressive turn has started to cross and foster, in many ways, the configuration of various objects, such as textbooks (TB). As part of the weaving of the Brazilian diplomacy device, the books carry not only the knowledge of promoting the teaching but the remnants of a network of practices (discursive and non-discursive) that activate trans-Brazilianity archives, to sustain, in a given historical period, the emergence of the Brazilian transnational identity (BTI). This research sought to study the relation of power and knowledge that inscribe the Brazilian transnational identity in the BDD, based on these networks of practices established in Portuguese textbooks for foreigners, produced and published by the Rede Brasil Cultural sectors and Brazilian Embassies. In order to verify both the identity manufactured in these textbooks and the mechanics and engineering, which in turn guarantee their conditions of existence. To shed light on those issues, we start from Discourse Analysis of frontiers, of historical and enunciative basis by invoking concepts such as the power-knowledge (FOUCAULT, 1984; 2005; 2008; [1981] 2018; DELEUZE, 1990; DELEUZE e GUATARRI, 1997; AGAMBEN, 2005; GREGOLIN, 2016), medium, scenes of enunciation (MAINGUENEAU 2004; 2006; 2008b; 2013; 2016; DEBRAY 1995, 1997, 2004), among other tools used during the analysis. In parallel, we held important dialogues with authors from different fields who forge their writings as resistance to certain configurations of (trans)national identity (FANON, 1968; GUATARRI e RONILK, 1996; BHABHA, 1998; HALL, 2005; BAUMAN, 2005; WALSH; 1994, 2019) and certain epistemic knowledge that supports, even today, a colonizing and segregating vision of (trans) Brazilianness (NASCIMENTO, 1978; GONÇALEZ and HASSENBELG, 1982; ORTIZ, 1986; 2013; SOUZA, 2000; 2009; 2017). The discussions and analyses show us the activation of language and culture as founding variables of transnational identity, however, promoted by a fragmented and disjointed foreign policy. Such fragmentation allows many speeches and different individuals to operate meanings in the textbook, allowing them to slide from a language book to an (inter)culture book, or even a symbol book of government (and not State) policies of government (and not State) policies dissemination and promotion of Brazil's image abroad. Concerning the activated imaginary that constitute the BTI and individuals transnationals, we noted three central points: the first one reinforces discourses hegemonic of a romanticized Brazil and racial paradise; the second one constitutes the ambivalence of activating a Brazil is progressive, plural, socially based, defender of the democratic rule of law and, at the same time, resignify mummified rags of the colonizing discourse (FANON, 1968); the third one, crossed by the first two, encourage reflection and engagement on the images of a Brazil of dialogue and conflict. This last one, permeated by a pedagogy of dialogue (GADOTTI; FREIRE; GUIMARÃES, 1994), criticizes the State through its official channels. Among other processes of regularities and ruptures, there is the distension of the senses of "foreigners" (called to belong to the nation) and the near invisibility of entire sectors of Brazilian society. Finally, we realized that, even in periods with high democratic values, in which the forging of voices peripheralized in State institutions, they provoke advances in the ways of making Brazil see and enunciate (inside and outside of its borders). The secular practices of segregation, exclusion, and genocide, operated by the discourses hegemonic, still cross, under different degrees, how the image of the (trans)national is constituted in the TBs – which often appears rooted in the vision of a white, masculine, hetero-normative, of a privileged class. This power mechanics prove to be even more dangerous when the democratic values lose space for the practice of a policy that sees in social bodies a frontier to say who is or not a citizen of the nation.
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    Influência da nióbia no óxido de alumínio eletrofundido para aplicações abrasivas
    (Universidade Federal de São Carlos, 2021-07-29)
    Passos, Edmilson Ricelli dos
    ;
    Morelli, Márcio Raymundo
    ;
    https://lattes.cnpq.br/0172837599844991
    ;
    https://lattes.cnpq.br/9808778046507780
    Abrasives are materials that have as main characteristics their cutting and grinding power. In its most common crystalline form, aluminum oxide, due to its high melting point, high hardness and mechanical resistance, is suitable for refractory and abrasive applications. With the increase in the consumption of abrasives and the market's need for more efficient grinding, polishing and cutting tools, this work aimed to verify the influence of niobium oxide on the physical chemical properties of electrofused aluminum oxide. Thus, the work addresses the electrofusion of calcined alumina with the addition of niobia, as well as a comparison of the mechanical properties of this material with emphasis on the abrasive characteristic, comparison with white fused aluminum oxide and brown fused aluminum oxide conventionally found in this market. The samples of the materials obtained were analyzed by X-Ray Diffraction and Fluorescence (DRX and FRX), wear test, instrumented nanohardness, real and bulk density, linear thermal expansion, refractoriness and microstructural characterization by Scan Electron Microscopy coupled to EDS. The results showed that the addition of niobia significantly influenced the increase in the abrasiveness of aluminum oxide, the wear test showed a removal of metallic material 6.6% higher than white fused aluminum oxide and 13.4% higher than brown fused aluminum oxide. Another important influence of the addition of Niobia in aluminum fused oxide was the increase in the thermal expansion coefficient and the reduction in refractoriness. While the white and brown aluminum oxides varied less than 1% of the initial length (at a temperature of 1250°C), the oxide with the addition of niobia presented a variation of 2.78% (at a temperature of 1174.8°C). Thus, it is proven in this work that niobia exerts a great influence on the physicochemical properties of fused aluminum oxides.
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    Abordagem baseada nas alterações do movimento escapular e investigação do medo relacionado à dor em indivíduos com dor no ombro
    (Universidade Federal de São Carlos, 2021-07-29)
    Kamonseki, Danilo Harudy
    ;
    Haik, Melina Nevoeiro
    ;
    https://lattes.cnpq.br/8240155487619947
    ;
    Camargo, Paula Rezende
    ;
    https://lattes.cnpq.br/7602596349127054
    Introduction: Shoulder pain is a common complaint with multifactorial characteristics that include biomechanical and psychosocial factors. Some interventions for shoulder pain are based on biomechanical changes commonly observed in those patients, such as changes in scapulothoracic muscles activation and scapular kinematics. However, there is no consensus on the efficacy of the biomechanics-based approach on scapular kinematics, scapulothoracic muscles activity, and clinical outcomes. The pain-related fear seems to play an important role in shoulder pain, but more information is needed to verify if it is a common condition for individuals with shoulder pain or if there are subgroups of individuals with distinct characteristics. Furthermore, the measurement properties of the Brazilian versions of two instruments that measure pain-related fear were not established in individuals with shoulder pain. This thesis is composed of four studies: Study 1: Objective: Systematically review the literature about the efficacy of electromyographic biofeedback for improving pain and function of individuals with shoulder pain. Methods: The databases Medline, EMBASE, CINAHL, PEDro, CENTRAL, Web of Science, and SCOPUS were searched in December 2020. Randomized controlled trials that investigated the effects of biofeedback electromyographic in individuals with shoulder pain and assessed pain and function were included. The level of evidence was assessed according to GRADE. Results and conclusion: Five studies were included with a pooled sample of 272 individuals. The biofeedback electromyographic was not superior to the other treatments for improving pain and function. However, the limited number of studies and very low quality of evidence do not support a definitive recommendation on the efficacy of biofeedback electromyographic for treating individuals with shoulder pain. Study 2: Objective: To compare the effects of scapular movement training to standardized exercises in individuals with shoulder pain. Methods: This is a single-blinded randomized controlled trial. Sixty-four individuals with chronic shoulder pain were randomly allocated to scapular movement training or standardized exercises for 8 weeks (2x/week). The primary outcome measure was the three-dimensional scapular kinematics. The secondary outcome measures were muscle activity of upper, middle, and lower trapezius, and serratus anterior, pain intensity, disability, fear-avoidance beliefs, kinesiophobia, and self-perceived health status. The scapular kinematics and muscle activity were assessed at baseline and 8th week, and the self-reported outcomes were collected at baseline, 4th, 8th, and 12th weeks. Results and conclusion: The scapular movement training showed significantly decreased scapular internal rotation in all angles of arm elevation and lowering at sagittal and scapular planes (mean difference [MD]: 2,8 - 4,1°), and at 30o of arm elevation and lowering at frontal plane (MD: 3,4 e 2,4 °, respectively), increased upper trapezius activity during arm lowering at scapular plane (MD: 10,3%), decreased middle trapezius (MD: 60.44%) and serratus anterior (MD: 9.9%) activity during arm lowering at frontal plane and arm elevation at the scapular plane, respectively, compared to standardized exercises. Both groups significantly improved pain, disability, fear-avoidance, kinesiophobia, and self-perceived changes over 4 weeks, which was sustained the remaining assessments. The observed between-group differences in scapular kinematics and muscle activity may not be clinically important. Both groups presented similar improvement over time on pain, disability, fear-avoidance beliefs, kinesiophobia, and self-perceived change in health condition. Study 3: Objective: To identify and describe phenotypes related to kinesiophobia, fear-avoidance, and pain catastrophizing, and determine clinical and demographic characteristics related to each phenotype as a function of self-reported function of the upper limbs in individuals with shoulder pain. Methods: One hundred and seventy-seven individuals with shoulder pain participated in this study. Tampa Scale of Kinesiophobia, Fear-Avoidance Beliefs Questionnaire, Pain Catastrophizing Scale, Disabilities of the Arm, Shoulder and Hand Questionnaire (DASH), Numerical Pain of Rating Scale, and the angular onset of pain during the elevation of the arm were measured in all participants. A cluster analysis was performed considering kinesiophobia, fear-avoidance, and pain catastrophizing, then clinical and demographic characteristics of clusters were used to model individual’s chance to belong to one of the clusters as a function of DASH. Results and conclusion: Two clusters were identified based on kinesiophobia, fear-avoidance, and pain catastrophizing. The cluster with worse pain-related fear profile presented (p < 0.05) higher age, worse function and higher pain intensity. This same cluster was also associated with involvement of the dominant side and worse function. Study 4: Objective: To verify the measurement properties of Brazilian versions of Fear-avoidance Beliefs Questionnaire (FABQ) and Tampa Scale of Kinesiophobia-11 (TSK) in individuals with shoulder pain. Methods: Individuals with shoulder pain and older than 18 years were included in this study. Structural validity was verified by exploratory and confirmatory factor analysis, which were used to identify dimensionality and to compare different structures of the FABQ and TSK. Test-retest reliability was assessed with intraclass correlation coefficient (3,1) and internal consistency with Cronbach’s alpha. Floor or ceiling effects were also investigated. Responsiveness was verified by effect sizes and area under ROC curve (AUC). Results and conclusion: Exploratory factor analysis identified three and two factors in the FABQ and TSK-11, respectively. All structures tested in this study did not fulfilled the criteria for adequate model fitting. FABQ and TSK-11 presented moderate to substantial reliability. One factor from FABQ and another from TSK-11 did not present adequate internal consistency. The floor effect was present in two factors from FABQ. The FABQ and TSK-11 showed small to large effect sizes and did not show adequate AUC. Therefore, FABQ and TSK-11 are multidimensional instruments, the internal structure was not clear and well-defined. The structural validity, reliability and responsiveness were found to be suboptimal in individuals with shoulder pain.
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    Produção de meios filtrantes a partir de garrafas PET recicladas para aplicações em filtração de ar com alta eficiência de coleta de nanopartículas através da técnica de Electrospinning
    (Universidade Federal de São Carlos, 2021-07-29)
    Bonfim, Daniela Patrícia Freire
    ;
    Aguiar, Mônica Lopes
    ;
    https://lattes.cnpq.br/0431688649128529
    ;
    https://lattes.cnpq.br/6489214115244937
    Air pollution and solid pollution are considered global problems, and endanger human health mainly due to the improper disposal of solid wastes, as the post-consumer plastic botlles.. The filtration process using fibrous filter media is widely used to remove particulate matter from an air stream because they are simple to use, low cost and can achieve high collection efficiencies. The properties of plastics make them potential candidates for nanofiber mat formers due to their attractive structural and mechanical characteristics. Thus, this research aimed to develop filtering media from PET waste using the electrospinning technique, dispensing with the use of microporous membranes as a support to remove nanoparticles from the air. The electrospinning process was carried out by changing the concentration of the polymer solution, the needle diameter, the processing time, the feed rate and the collector rotation speed. The average diameter of micro and nanofibers of the filter media produced ranged from 4.88 to 0.6 µm and it was possible to conclude that the mechanical strength increased with the reduction of the fiber diameter. The filter media produced showed high mechanical strength (4.5 MPa), adequate permeability (6.3x10-8 m2) and high porosity (99%), reaching high collection efficiency (about 100% for particles from 7 to 300 nm) and low pressure drop for the removal of viable aerosol nanoparticles. Therefore, the developed electrospun membranes can be applied as indoor air filters, where extremely clean air is needed (e.g., hospitals, clean zones of pharmaceutical and food industry, aircraft, among others) and also for making protective fabrics and PPE's.
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    Efeito do material particulado atmosférico (MPA) sedimentável proveniente da atividade siderúrgica sobre a função cardíaca de tilápia, Oreochromis niloticus
    (Universidade Federal de São Carlos, 2021-07-30)
    Adorno, Henrique Aio
    ;
    Monteiro, Diana Amaral
    ;
    https://lattes.cnpq.br/0358411551730768
    ;
    https://lattes.cnpq.br/7384615643107023
    The industrial activity for obtaining and processing metal alloys, iron and steel result in the emission of Sedimentable Atmospheric Particulate Material (SAPM). Mining-steel industries located in the “Complexo do Tubarão”, in Metropolitan Region of Vitoria (MRV), Vitoria – ES, emit a metal smoke commonly called "black powder" that contains a varied composition of metals and metal nanoparticles that are deposited in aquatic environments. Faced with a scenario that seeks to produce information that can help the sustainable management of water resources, the objective of this study was to evaluate the possible effects of acute exposure (96 hours) of sublethal concentrations of 0.01 g.L-1, 0.1 g.L-1, and 1.0 g.L-1 of SAPM on myocardial contractility of Nile tilapia, Oreochromis niloticus. The group exposed to 1.0 g.L-1 of SAPM showed significantly higher values of contraction force (Fc) and cardiac pumping capacity (CPC) at all stimulation frequencies. In the exposed animals, time-dependent parameters (TPT = time to peak tension, and THR = time to 50% of relaxation) were lower, while contraction and relaxation rates were higher. All groups exhibited a Fc decay after the non-physiological diastolic pause of 300 seconds, which was more conspicuous in the exposed groups, suggesting a prominent role of the Na +/Ca2+ (NCX) exchanger in calcium extrusion. As the 1.0 g.L-1 concentration of SAPM showed pronounced effects on cardiac contraction, we also investigated the effects of this exposure on hematological parameters and plasma biomarkers of stress response and oxidative stress. Alterations in myocardial contractility in MPAS-exposed fish were associated with a stress response characterized by significant increases in plasma cortisol and glucose levels. Tilapia exposed to SAPM also showed a significant reduction in hemoglobin content indicating a possible hypoxemia state, which may require adjustments in cardiac output, with increased Fc to increase systolic volume. The exposed fish showed higher values of hepatosomatic index and relative ventricular mass, probably associated with the overload of activity of the heart and liver. Additionally, SAPM exposure induced significant increases in plasma levels of lipid peroxidation and protein carbonylation, indicating oxidative stress and reflecting an imbalance of redox homeostasis. NCX protein expression showed no significant difference between the groups, indicating that the positive inotropic and lusitropic effects are associated with β-adrenergic responses during stress situations. Thus, the effects of SAPM may negatively affect the adaptation, survival and reproductive success of tilapia, as the energy requirement to maintain the physiological patterns of the cardiovascular system and the detoxification processes demanded by SAPM exposure is high.
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    Influência da sombra do dossel temporário de um sistema agroflorestal na maturação de frutos de café
    (Universidade Federal de São Carlos, 2021-07-30)
    Leite, Paulo Henrique Marquezini
    ;
    Oliveira, Renata Evangelista de
    ;
    Bigaton, Ademir Durrer
    ;
    https://lattes.cnpq.br/6777223792862756
    ;
    https://lattes.cnpq.br/1201801613118649
    In Brazil, coffee trees have been included in agroforestry systems, mainly due to climatic emergencies and increased demand for specialty coffees. The shading levels inside a multi-layered agroforest depend on the design, management and, mainly, on the development time and evolution of the system. Understanding these variations over time, as well as the effects of temporary canopy on coffee production components, can contribute to the definition of more efficient agroforestry designs, especially in agroforestry systems (SAFs) in the establishment phase. In a four-year-old young agroforestry coffee plantation, in the process of stratification and establishment with a temporary canopy formed by Ricinus communis L., we aimed to evaluate the shading levels and its influence on the maturation of coffee (Coffea arabica L.) Bourbon amarelo . The shading was determined at four distances, at 1 m (D1), 4 m (D2), 7 m (D3) and 10 m (D4), from the sunniest edge (North face) to the interior of the SAF. We evaluated the shading levels, calculated by the difference of photosynthetically active radiation (PAR) in full sun and inside the SAF, quantifying the total volume of produced fruits, the percentage of dry fruits and the dry biomass of the coffee tree. As the distances from the edge to the interior of the SAF increased, the greater was the shading level. The evaluated coffee trees responded homogeneously within each distance, the more shaded ones produced a greater volume of fruits and a smaller percentage of them, dry. Coffee dry biomass was higher at distance D4. This work contributes to the understanding of how environmental factors, design and management of agroforestry influence the maturation of coffee fruits, a crucial factor for ordering the harvest and production of better quality coffees.
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    Distribuições discretas para duas observações inflacionadas
    (Universidade Federal de São Carlos, 2021-07-30)
    Hebling, Luisa
    ;
    Conceição, Katiane Silva
    ;
    https://lattes.cnpq.br/5789619620619667
    ;
    https://lattes.cnpq.br/2173304528541755
    Count data is often found in many real applications and some observations may occur in the data set in an excessive amount. In many real problems it is quite common for the data set to contain excesses of zero and one observations. In a more general context, k1 and k2 are defined as observations of a particular data set that have discrepancy (excess) in their frequencies, making modeling from traditional discrete distributions inappropriate. Thus, the main objective of this work is to propose the k1 and k2 Inflated Power Series family of distributions, aiming to model data sets that present such discrepancy in the observations k1 and k2. In order to estimate the parameters we consider classical approach, with the maximum likelihood method, using a hurdle version of distributions. Some applications considering real data sets will be presented.
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    Análise de falha de martelos oscilantes de desfibradores utilizados em usinas sucroalcooleiras
    (Universidade Federal de São Carlos, 2021-07-30)
    Sasso, Ricardo Aparecido
    ;
    Koga, Guilherme Yuuki
    ;
    https://lattes.cnpq.br/0933095081175012
    ;
    Gargarella, Piter
    ;
    https://lattes.cnpq.br/4641435644243916
    Sugarcane mills have demanded more control of their production line, reduced loss of raw material, and a longer period before maintenance of their equipment, aiming to increase their profitability. The main station of this process is the mill responsible for crushing the sugar cane. Its components such as knives, hammers, and rollers are subject to degradation processes, mainly wear and corrosion, decreasing production efficiency and increasing the maintenance costs. This work aims to perform the failure analysis of hammers coated with weld, removed from a mill shredder after use. Through compositional characterization techniques, it was determined that the base material is a 1030 carbon steel, and the coating is a high Cr (22,2 %wt) and C (3,65 %wt) ferrous alloy. The coating showed greater resistance to abrasive wear compared to the base and reference material (410 stainless steel), it has greater hardness and hard carbides (type M7C3) that act as reinforcement and protection elements against the removal of the soft matrix material of ferrite and austenite by abrasive action. Despite the complexity of sugarcane juice, composed of chlorides, sulfides, and organic acids, the cyclic polarization curves did not show significant differences between the materials tested in this corrosive environment. The 410 stainless steel had better performance against corrosive effects, due to the complete dissolution of Cr in the solid solution, which ensured the formation of a protective passive film, which, unlike the coating, with a high content of Cr, creates carbides in excesses and interfaces depleted in Cr, representing preferential points for corrosion. The cracks in the coating allowed the penetration of the sugarcane juice, and subsequent detachment of the weld by impact, exposing the base material to abrasive wear and corrosive. Greater control during the coating preparation process and the use of a base material with greater corrosion resistance could significantly extend the life of the hammers.
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    Para que servem as eleições municipais? Estratégias políticas na competição local
    (Universidade Federal de São Carlos, 2021-07-30)
    Martins, Thais Cavalcante
    ;
    Kerbauy, Maria Teresa Miceli
    ;
    https://lattes.cnpq.br/4762029784021248
    ;
    https://lattes.cnpq.br/5764763788709997
    The objective of this research is to investigate the strategies of political actors in local electoral competition, focusing on two dimensions. The first concerns legitimate and formal means, with an emphasis on the provisions established by the electoral system that increase one's chances of accessing power. It also explores the levels of competition as well as the conditions of competition. The second dimension delves into the instruments that enable candidates and parties to monitor elections and the occurrence of electoral irregularities. Such devices are assessed as a political strategy available to candidates and parties both before and after voting. The general hypothesis is that variation in strategy use is related to factors exogenous to elections, but it is also due to institutional factors, such as the level of competitiveness in municipal disputes. Based on an analysis of electoral, socioeconomic, and jurisprudence data, descriptive statistics and logistic regression techniques were used to investigate the variation and test the hypothesis. The study focuses on the dispute for the municipal executive position between 2000 and 2016, covering all Brazilian municipalities. The findings support the hypothesis and demonstrate that, even though elections have become more competitive and monitored, they continue to coexist with abusive practices, which are not necessarily limited to the country's less developed territories.
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    Influência de modificações superficiais na resistência à corrosão e na bioatividade da liga beta ti-40nb para aplicações biomédicas
    (Universidade Federal de São Carlos, 2021-07-30)
    Ricci, Virgilio Pereira
    ;
    Jorge Júnior, Alberto Moreira
    ;
    https://lattes.cnpq.br/6360362248108490
    ;
    Afonso, Conrado Ramos Moreira
    ;
    https://lattes.cnpq.br/2176215981291453
    β-titanium (Ti) alloys have great applicability in the biomedical area due to properties such as low density, high corrosion resistance, low elasticity modulus (E), and biocompatibility. However, these alloys are not bioactive. It is necessary to make surface modifications producing bioactive surfaces and with better electrochemical properties. For these reasons, this work evaluated the bioactivity performance and corrosion resistance of the Ti-40Nb alloy modified superficially by anodization, producing the amorphous nanostructures of nanotubes (NTs-AM) and nanopores (NPs-AM). Initially, the annealing was carried out on anodized samples with amorphous nanostructure to reduce the alloy’s E and crystallize the amorphous nanostructures in a mixture of anatase and rutile, obtaining these characteristics with annealing at 550 °C, namely NTs-HT and NPs-HT. The precalcification (PC) process was performed to increase the bioactive behavior of NTs-HT and NPs-HT, that is, NTs-PC and NPs-PC. The electrochemical behavior was studied by open circuit potential (OCP), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). Samples with NTs-HT and NPs- HT showed the highest corrosion potential (Ecorr) and lower passivation current density (ipass), with the lowest ipass of ~0,3 μA/cm² being observed in NPs-HT. The EIS simulation by equivalent electrical circuits (EEC), the NPs-HT showed greater resistance and thickness of the barrier layer. After 14 days of soaking in SBF, it was not observed HAp formation in the unmodified substrate, NTs/NPs- HT conditions exhibited moderate apaite formation. In contrast, NTs/NPs-PC samples showed high apatite formation, with apatite mass gain ~3.5x higher than anodized and annealed samples.
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    Interações entre estrutura da vegetação e fertilidade do solo na decomposição da matéria orgânica em diferentes usos do solo
    (Universidade Federal de São Carlos, 2021-07-30)
    Bessi, Débora
    ;
    Tanaka, Marcel Okamoto
    ;
    https://lattes.cnpq.br/2768658925977757
    ;
    https://lattes.cnpq.br/0893444898265301
    Forests play a fundamental role in providing ecosystem functions and services. In particular, the relationship between forest and soil is an important link for ecosystem functioning and maintenance of services such as nutrient cycling. Despite this, a high loss of natural forest area has been observed, mainly due to the conversion into agricultural area, strongly impacting the biogeochemical cycles. Agroforestry systems and ecological restoration practices are capable of playing a fundamental role in the resumption of ecosystem functions. It is expected that the introduction and growth of the plant community favors nutrient cycling and carbon fixation, which are strongly influenced by organic matter decomposition rates. The litter decomposition process is complex, involving interactions between physical, chemical and biological soil characteristics, litter chemical characteristics, local vegetation structure and climatic variation. Thus, this study aimed to evaluate the effects of plant structure and soil quality, in areas with different land uses, on the decomposition processes of organic matter as estimated by decomposition rates k and stabilization factor S. We used the TBI (Tea Bag Index) method to assess k and S and evaluate decomposition in agroforestry systems, successional stands at different ages of forest restoration and mature riparian forests. The direct and indirect effects of the sampled variables were estimated using structural equation models. Our results showed that intensive pasture systems and pastures intercropped with crops present a more dynamic nutrient cycling (higher k), whereas in areas with silviculture inclusion there was a greater contribution of recalcitrant organic matter and material stabilization (higher S). When comparing riparian forest areas, restored areas and pastures, the results indicated that the stabilization of organic material is greater in forest areas compared to pasture areas, with a tendency to increase with the advancement of succession and soil fertility. In contrast, decomposition rates were higher in open areas under pasture, but also showed a positive variation with nutrient content. These results suggest that the diversification of integration systems favors nutrient cycling and carbon sequestration due to the lower nutrient loss through decomposition and stabilization of the organic matter, contributing to the sustainable management of pastures. In addition, plant restoration practices can be a good strategy to increase the input of organic material into the soil considering the increase in organic matter stabilization when compared to pastures, contributing to the improvement of its quality and, mainly, increasing carbon sequestration via stabilized material.
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