Educação Física Escolar: práticas de pesquisa e saberes científicos em revista (1979-2009)

Educação Física Escolar: práticas de pesquisa e saberes científicos em revista (1979-2009

Adubação de cobertura na batata-doce com doses combinadas de nitrogênio e potássio.

Resumo: A adubação balanceada de N e K frequentemente aumenta o desempenho das lavouras, contudo, a falta de um desses nutrientes em solos deficientes pode levar a decréscimos na resposta ao outro. O objetivo deste trabalho foi avaliar a produtividade de batata-doce comercializável, a quantidade de raízes tuberosas para descarte e a diagnose foliar de lavoura de batata-doce adubada com N e K. O experimento foi realizado em lavoura comercial, em Presidente Prudente-SP, de fevereiro a junho de 2007, em um Argissolo Vermelho distroférrico de textura média. O delineamento experimental foi em blocos completos casualizados, com quatro repetições, no esquema fatorial 4 x 4, com 0, 30, 60 e 120 kg há de N (uréia), em interação com 0, 30, 60 e 120 kg há de KO (KCl), aplicados em cobertura aos 39 dias após o plantio. A cultura da batata-doce é responsiva à adubação nitrogenada e potássica de cobertura, porém, os maiores incrementos de produtividade são alcançados com as doses de N e K combinadas. A adubação de cobertura com N e K não acarreta em aumento da quantidade de raízes tuberosas impróprias para a comercialização. O maior incremento de produtividade da batata-doce é alcançado com a adubação de cobertura combinada com 100 kg de N ha mais 120 kg de K. Abstract: Balanced fertilizations with N and K often increase the performance of crops, however, when there is absence of one of these nutrients in poor soils, can reduce crop response to fertilization with the other. The objective of this work was to evaluate the productivity of sweet-potato, the amount of sweetpotato without quality, and leaf nutrients analysis, of sweet-potato crop fertilized with N and K. The trial was conducted in farming for commercial production, in Presidente Prudente, São Paulo State, during February-June 2007, in a dystrophic Ultisol of medium texture. The experimental design was a randomized complete block design, with four replications, on factorial 4 x 4: levels of 0, 30, 60 and 120 kg N ha (urea source) combined with levels of 0, 30, 60 and 120 kg KO ha (KCl source), applied to 39 days after planting of the crop. The sweet-potato is responsive to topdressing application with nitrogen and potassium, however, the greatest increases in productivity occur when doses of N and K are combined. Fertilization with N and K not increase the amount of sweet-potato without quality marketing. The highest increase in productivity of sweet-potato is reached with topdressing combined with 100 kg N ha plus 120 kg KO ha

Salvage Flexor Hallucis Longus Transfer for a Failed Achilles Repair: Endoscopic Technique

Flexor hallucis longus (FHL) transfer is a well-established treatment option in failed Achilles tendon (AT) repair and has been routinely performed as an open procedure. We detail the surgical steps needed to perform an arthroscopic transfer of the FHL for a chronic AT rupture. The FHL tendon is harvested as it enters in its tunnel beneath the sustentaculum tali; a tunnel is then drilled in the calcaneus as near to the AT footprint as possible. By use of a suture-passing device, the free end of the FHL is advanced to the plantar aspect of the foot. After adequate tension is applied to the construct, the tendon is fixed in place with an interference screw in an inside-out fashion. This minimally invasive approach is a safe and valid alternative to classic open procedures with the obvious advantages of preserving the soft-tissue envelope and using a biologically intact tendon

Toward a universal theory of the human group: sociological systems framework applied to the comparative analysis of groups and organizations

Drawing on a sociological multi-level, dynamic systems approach – actor-system-dynamics (ASD) -- which has been developed and applied in institutional, organizational, and societal analyses, we formulate a general model for the comparative analysis of social groups and organizations. This social systems approach has not been previously applied in the group area. We claim that the approach can be systematically and fruitfully applied to small as well as large groups and organizations as a methodology to understand and analyze their structure, functioning and dynamics. A group is considered a system with three universal subsystems on which any human social organization, including small groups, depends and which motivate, shape and regulate group activities and productions. The subsystems are bases or group requisites – necessary for group “functioning” and performance in more or less orderly or coherent ways; on this basis a group may be able to realize its purposes or goals(as well as possibly some members’ personal goals) and maintain and reproduce the group. The group bases consist of: first, a rule regime (collective culture)defining group identity and purpose, shaping and regulating roles and role relationships, normative patterns and behavioral outputs; second, an agential base of group members who are socialized or partially socialized carriers of and adherents to the group’s identity and rule regime; of relevance here are involvement/participation factors motivating member to adhere to, accept, and implement key components of the rule regime; third, there is a resource base, 2 technologies and materials, self-produced and/or obtained from the environment, which are essential to group functioning and key group performances. Section I briefly presents the framework and outlines the group systems model, characterized by its three universal bases or subsystems and its finite universal production functions and their outputs as well as the particular context(s) in which groups function. For illustrative purposes, the section identifies three major ideal-type modalities of group formation: informal self-organization by agents, group construction by external agents, and group formation through more or less formal multi-agent negotiation. The general systems model presented in Section II characterizes a social group not only by its three universal bases but by its finite universal production functions (elaborated in Section IV) and its outputs as well as by its shared places (situations for interaction) and times for gathering and interacting. Group productions impact on the group itself (reflexivity) and on its environment. These outputs, among other things, maintain/adapt/develop the group bases (or possibly unintentionally undermine/destroy them) Thus, groups can be understood as action and interaction systems producing goods, services, incidents and events, experiences, developments, etc. for themselves and possibly for the larger environment on which they depend for resources, recruits, goods and services, and legitimation. The model provides a single perspective for the systematic description and comparative analysis of a wide diversity of groups (Sections III and IV). A major distinctive feature in our systems approach is the conceptualization of rules and rule regimes (Sections II, III, IV, and V). Finite universal rule categories (ten distinct categories) are specified; they characterize every functioning social group or organization. A rule regime, while an abstraction is carried, applied, adapted, and transformed by concrete human agents, who interact, exchange, exercise power, and struggle within the group, in large part based on the rule regime which they maintain and adapt as well as transform. The paper emphasizes not only the systemic character of all functioning groups – universally their three bases and their output functions together with feedback dynamics -- but also the differentiating character of any given group’s distinct rule configuration (Section IV). For illustrative purposes Section IV presents a selection of rule configurations characterizing several ideal types of groups, a military unit, a terrorist group, a recreational or social group, a research group, a corporate entity Section V considers the dynamics of groups in terms of modification and transformation of group bases and their production functions. The group system model enables us to systematically identify and explicate the internal and external factors that drive group change and transformation, exposing the complex interdependencies and dynamic potentialities of group systems. Section VI sums up the work and points out its scope and limitations. The group systems model offers a number of promising contributions: (1) a universal systems model identifies the key subsystems and their interrelationships as well as their role in group production functions/outputs and performances; (2) the work conceptualizes and applies rules and rule complexes and their derivatives in roles, role relationships, norms, group procedures and production functions; (3) it identifies the universal categories of rules making up a rule regime, a major subsystem for any functioning group; (4) the model conceptualizes particular “group rule configurations” – rule regimes with specified rules in the universal rule categories—for any given group; groups are identifiable and differentiable by their rule configurations (as well as by their resource and agency bases); (5) it conceptualizes the notion of the degree of coherence (alternatively, degree of incoherence) of rule configurations characteristic of any given group and offers an explanation of why group attention is focused on the coherence of rules in certain group areas; (6) the systems model suggests an interpretation of Erving Goffman’s “frontstage backstage” distinction in terms of alternative, differentiated rule regimes which are to a greater or lesser extent incoherent with respect to one another; moreover, the participants who are privy to the differentiation navigate using a shared rule complex to translate coherently and consistently 3 from one regime to the other, using appropriate discourses; (7) incoherence, contradiction, conflict and struggle relating to rule regimes are considered part and parcel of group functioning and development; (8)group stability and change are explicated in terms of internal mechanisms (e.g., governance, innovation, and conflict) as well as external mechanisms (resource availability, legal and other institutional developments, population conditions), pointing up the complex systemic interdependencies and dynamic potentialities of group systems; (9) given the multi-level dynamic systems framework (i.e., ASD) that has been applied in a range of special areas (economic, political, technological, environmental, bio-medical, among others) its applicataion in the field of groups is a promising step toward achieving greater synthesis in sociology and social science. This 2nd edition of the paper has been substantially rewritten and extended: the current text is twice the number of pages of the original – and there has been much restructuring of the manuscript as a whole. Tables and figures have been added. Substantively, we developed the following features of the work in the 2nd edition: (1) more attention has been given to tension, conflict, and conflict resolution in groups; (2) we also stressed group requisites for sustainability and group production functions; (3) a section on group formation with illustrations has been added; (4) we have expanded our attention to group rule configurations which differentiate groups from one another but also enable systematic comparisons; (5) we have much expanded consideration of the dynamics of group change and transformation

A universal theory of social groups: the actor-system-dynamics approach to agents, rule regimes, and interaction processes

Drawing on multi-level, dynamic systems theory in sociology which has been developed and applied in institutional, organizational, and societal analyses, we formulate a general theory of social groups. This social systems approach has not been previously applied in the group area. We claim that this particular systems approach can be systematically and fruitfully applied to small as well as large groups to understand and analyze their functioning and dynamics. In this article, we refer to a group as an aggregation of persons/social agents that is characterized by (1) shared group identity, (2) a shared rule regime (collective culture) shaping and regulating their roles and role relationships and group behavioral outputs (3) its bases of membership and adherence or commitment to the group, its identity and rule regime, (4) its technologies and material resources used in group interactions, 2 performances, and productions (5) it shared places (situations for interaction), and (6) its times for gathering and interacting. The theory identifies three universal bases on which any human group or social organization, including small groups, depends and which motivate, shape and regulate group activities and productions (Section II). The bases are group requisites – necessary for group “functioning” and interacting in more or less orderly or coherent ways, realizing group as well as possibly members’ goals and maintaining and reproducing the group. The group bases consist of, first, a rule regime or social structural base; second, an agential base of group members socialized or partially socialized carriers of and adherents to the group’s rule regime; of importance here are involvement/participation factors motivating member to adhere to, accept, and implement the rule regime; third, there is a resource base, technologies and resources self-produced and/or obtained from the environment, which are essential to key group activities. In the theory presented here in Section II, a social group is not only characterized by its three universal bases but by its universal functions, group actions and outputs -- its interactions and productions/performances and their outcomes and developments including the impact of their productions on the group itself (reflexivity) and on its environment (see Figure 1). These outputs, among other things, maintain/adapt/develop core group Bases (or possibly unintentionally undermine/destroy them). Thus, groups can be understood as action/interaction systems producing goods, services, incidents and events, experiences, developments, etc. for themselves and possibly for the larger environment on which they depend for resources, recruits, goods and services, legitimation, etc. The theory identifies the six (6) universal system functions of groups. A major distinctive feature in our systems approach is the theory of rule regimes, specifying the finite universal rule categories (ten distinct categories) that characterize every functioning social group or organization. A rule regime, while an abstraction is carried, applied, adapted, and transformed by concrete human agents, who interact, exchange, exercise power, and struggle within the group, in large part based on the rule regime which they maintain, adapt, and transform. We emphasize not only the systemic character of all functioning groups – universally their three bases and their six output functions together with feedback dynamics -- but also the differentiating character of any given group’s particular rule configuration. The article ends with a discussion of two major theoretical implications: (1) the identification and analyses of any given group’s particular rule configuration which characterize that group and is sustained under relatively stable internal and external conditions (Section III); for illustrative purposes we present in Section IV a selection of few simple rule configurations that characterize several diverse types of groups. (2) the transformation of group bases and their interaction/production functions. The theory enables from a single framework the systematic description and comparative analysis of a wide diversity of groups, as illustrated in Sections III and IV

The Role of Biomarkers, Metabolomics, and COVID-19 in Venous Thromboembolism—A Review of Literature

In recent years, the field of venous thromboembolism has undergone numerous innovations, starting from the recent discoveries on the role of biomarkers, passing through the role of metabolomics in expanding our knowledge on pathogenic mechanisms, which have opened up new therapeutic targets. A variety of studies have contributed to characterizing the metabolic phenotype that occurs in venous thromboembolism, identifying numerous pathways that are altered in this setting. Among these pathways are the metabolism of carnitine, tryptophan, purine, and fatty acids. Furthermore, new evidence has emerged with the recent COVID-19 pandemic. Hypercoagulability phenomena induced by this viral infection appear to be related to altered von Willebrand factor activity, alteration of the renin-angiotensin-aldosterone system, and dysregulation of both innate and adaptive immunity. This is the first literature review that brings together the most recent evidence regarding biomarkers, metabolomics, and COVID-19 in the field of venous thromboembolism, while also mentioning current therapeutic protocols

Experimental characterization and numerical analysis of the 4H-SiC p-i-n diodes static and transient behaviour

Steady-state and turn-off switching characteristics of aluminium-implanted 4H-SiC p-i-n diodes designed for high current density operation, are investigated experimentally and by mean of numerical simulations in the 298-523 K temperature range. The diodes present circular structure with a diameter of 350 &#956;m and employ an anode region with an aluminium depth profile peaking at 6?1019 cm&#8722;3 at the surface. The profile edge and the junction depth are located at 0.2 and 1.35 &#956;m, respectively. At room temperature the measured forward current density is close to 370 A/cm2 at 5 V with an ideality factor always less than 2 before high current injection or device series resistance became dominant. The transient analysis reveals a strong potential of this diodes for use in high speed, high power applications, especially at high temperature, with a very low turn-off recovery time (<80 ns) in the whole range of test conditions. The simulated results match the experimental data, showing that the switching performance is mainly due to the poor minority charge carrier lifetime estimated to be 15 ns for these implanted devices

Some Considerations on the Behaviour of Bolted Stainless-Steel Beam-to-Column Connections: A Simplified Analytical Approach

Stainless-steel has proven to be a first-class material with unique mechanical properties for a variety of applications in the building and construction industry. High ductility, strain hardening, durability and aesthetic appeal are only a few of them. From a specific point of view, its nonlinear stress–strain behaviour appears capable of providing a significant increase in the rotational capacity of stainless-steel connections. This, in turn, may provide significant benefits for the overall response of a structure in terms of capacity and ductility. However, the bulk of the research on stainless-steel that has been published so far has mostly ignored the analysis of the deformation capabilities of the stainless-steel connections and has mostly focused on the structural response of individual members, such as beams or columns. For such a reason, the present study aims to contribute to the general understanding of the behaviour of stainless-steel connections from a conceptual, numerical and design standpoint. After a brief review of the available literature, the influence of the use of stainless-steel for column–beam connections is discussed from a theoretical standpoint. As a novel contribution, a different approach to compute the pseudo-plastic moment resistance that takes into account the post-elastic secant stiffness of the stainless-steel is proposed. Successively, a refined finite element model is employed to study the failure of stainless-steel column–beam connections. Finally, a critical assessment of the employment of carbon-steel-based design guidelines for stainless-steel connections provided by the Eurocode 3 design (EN 1993-1-8) is performed. The findings prove the need for the development of novel design approaches and more precise capacity models capable of capturing the actual stainless-steel joint response and their impact on the overall ductility and capacity of the whole structure