Salinity-induced effects on transpiration rate, stomatal conductance and leaf area of three olive (Olea europaea L.) varieties

Transpiration of two year-old olive trees of three different varieties, Arbequina, Cobrançosa and Galega (18 trees per variety), irrigated with three levels of salt (0, 80 or 200 mM NaCl) for about 90 days, was measured by a gravimetric method. To determine leaf area, each tree was photographed from the side against a white background and the total area of each projected image was determined with ImageJ software. To calibrate these area determinations, one tree of each variety was subsequently stripped of all its leaves and its total leaf area was accurately measured. A correlation was then obtained between the area on the photograph of this particular tree and the total area of the detached leaves of the same tree. Using the leaf area determined by this procedure, transpiration rates of the trees could be calculated. Knowing leaf and air temperatures and RH, it was possible to determine the difference in molar fraction of water between the leaf and the air. Using this and the values of the transpiration rate, stomatal conductance could be calculated (gs calc) and compared with the conductance measured on the same trees with a porometer (gs). Actual leaf area of a plant was 1,40 (Arbequina), 1,42 (Cobrançosa) or 1,24 (Galega) times the area measured with ImageJ on the photograph of the same plant. Leaf area of the trees, on average of all salt irrigations, was significantly higher on Arbequina (0,187 m2) then on the other two varieties (0,138 m2 or 0,148 m2, for Cobrançosa or Galega, respectively), but did not differ significantly in percentage of controls (0 salt). On average of all three varieties, leaf area was also higher on plants irrigated without salt (0,181 m2) than on plants exposed to 80 or 200 mM NaCl (0,152 m2 or 0,140 m2, respectively), which did not differ between them. The same significant difference was observed when leaf area was expressed as percentage of controls. Transpiration rate was significantly higher on Cobrançosa (1,17 mmol m-2 s-1), on average of all treatments, but there were no significant differences between Arbequina (1,08 mmol m-2 s-1) and Galega (0,82 mmol m-2 s-1). In percentage of controls, there were no significant differences between varieties. Salt reduced significantly the transpiration rate in all varieties, both the actual and percentual values, to about 50% or 30% of controls when exposed to 80 mM or 200 mM NaCl, respectively. Stomatal conductance (gs), assessed by porometry, was significantly higher in control plants, mainly in Cobrançosa (102 mmol m-2 s-1), then in Arbequina (77 mmol m-2 s-1) and the lower values were found in Galega (51 mmol m-2 s-1). Salt reduced gs, on average of the three varieties to 30% or 10% of controls on exposure to 80 mM or 200 mM NaCl, respectively. Calculated (gs calc) and measured (gs) values of stomatal conductance showed a close relation between them (0,967, R2 = 0,837) which indicates this non-destructive method to determine whole-plant leaf area to be reasonably accurate.

Motivations to interact with brands on Facebook – Towards a typology of consumer–brand interactions

In recent years, Facebook and other social media have become key players in branding activities. However, empirical research on consumer–brand interactions on Facebook is still in its infancy. Therefore, the aim of this research is to provide additional insights to brand managers on how to adapt their approaches to increase consumers’ interactions with brands on Facebook. In this study, we apply the uses and gratification theory proposed by Katz to develop a new typology of consumers based on consumer motivations to interact with brands on Facebook, and explore the type and intensity of these interactions. We identify five main motivations that might influence consumers’ interactions with a brand on Facebook: (i) social influence, (ii) search for information, (iii) entertainment, (iv) trust and (v) reward. Building on these five motivations, a classification using clustering techniques reveals four different groups of consumers: (i) ‘brand detached’, (ii) ‘brand profiteers’, (iii) ‘brand companions’ and (iv) ‘brand reliants’. Our results provide valuable and applicable insights for social media marketing activities, which will assist brand managers to develop strategies for effectively reaching and influencing the most desirable groups of consumers.

Estrutura e processo de formação das formas culturais: o caso do cante alentejano

Qualquer sistema de práticas individualizado que se distinga aos olhos dos seus praticantes é caracterizável pela forma que assume e pelo seu conjunto de atributos. A essa forma corresponde uma moldura analítica que encontra o seu equivalente real nos actores e no modo como formulam discursos sobre as suas práticas, do qual emerge um conjunto de normas. Por conseguinte, a forma tanto é uma construção metodológica externa para a descrição do sistema e das suas condições de existência como uma realidade dinâmica, produtora de identidades culturais. Pretendemos substituir uma noção imprecisa de “forma cultural” por um conceito estruturado, definindo-a como sistema de referência que os membros de uma cultura partilham e que define e regula as produções e reproduções culturais e que comporta um elemento estruturante, um sistema normativo e uma dinâmica social. O caminho para essa conceptualização implica a aplicação do conceito a um objecto empírico, operação que realizamos ao analisar o Cante Alentejano – conjunto de maneiras de cantar observadas do Alentejo – enquanto forma cultural; Abstract: Any system of practices that can be individualized and distinguished by its practitioners can be characterized through the form it assumes and the set of its attributes. Such form corresponds to an analytical framework that has its equivalent in the real actors world and in the ways they formulate utterances about their practices, from which emerges a set of rules. Therefore, the form is both an external methodological construction needed for the system’s description and a dynamic “emic” reality that produces cultural identities. We intend to replace an inaccurate notion of "cultural form" by a structured concept. We will define it as the reference system that the members of a given culture share and that guides and regulates the cultural processes of production and reproductions of the system. The concept comprises a structural element, a normative system, and a social dynamic. The path to this conceptualization implies applying the concept to an empirical object, operation that will be held by analyzing Cante Alentejano – a set of ways of singing from Alentejo – as a cultural form.

Autenticidade, reconhecimento e dádiva - Para uma renovação dos direitos humanos

Esta investigação pretende articular a Teoria do Reconhecimento de Axel Honneth com a Ética da Autenticidade de Charles Taylor e complementar este diálogo com a Teoria da Dádiva, que tem vindo a ser desenvolvida por vários autores franceses e latino-americanos. A autenticidade foi, ao longo da história ocidental, considerada como sendo uma busca individual do eu, baseada numa racionalidade desvinculada, que não considerava os horizontes de sentido ou as relações com os outros significantes. Através da teoria de Taylor, essa perspetiva mudou: a autenticidade agora é descrita como um ideal moral dialógico, fundamentada no reconhecimento. Neste percurso do reconhecimento procuramos aprofundar não só a ideia de luta, mas também a relação de mutualidade da dádiva fundamentada no reconhecimento simbólico. Nesse sentido, o individualismo, neutralismo e a distinção entre esfera pública e privada, usados como critérios hermenêuticos para os Direitos Humanos, são substituídos pela autenticidade, reconhecimento e dádiva, num aprofundamento político-normativo de forma a contribuir para uma sociedade mais inclusiva e para a renovação ética dos Direitos Humanos; ABSTRACT: This research aims to articulate Axel Honneth’s Theory of Recognition with Charles Taylor’s Ethics of Authenticity, supplementing and weaving them with the Theory of Gift, which has been developed by several French and Latin-American authors. Authenticity has been considered, throughout western history, to be an individual search of the self, based on a detached rationality that did not take into consideration the horizons of meaning/sense or relations with the significant others. Along with Taylor’s theory, such perspective has changed: authenticity is now described as a dialogic moral ideal, grounded on recognition. In this route towards recognition we seek to deepen not only the idea of struggle, but also the mutual relation of gift grounded on symbolic recognition. In that sense, individualism, neutrality and distinction between public and private spheres, used as hermeneutic criteria for Human Rights, are replaced by authenticity, recognition and gifting, in a political-normative depth, in order to contribute to a more inclusive society and to an ethical renewal of Human Rights.

Motivations to interact with brands on Facebook – Towards a typology of consumer–brand interactions

In recent years, Facebook and other social media have become key players in branding activities. However, empirical research on consumer–brand interactions on Facebook is still in its infancy. Therefore, the aim of this research is to provide additional insights to brand managers on how to adapt their approaches to increase consumers’ interactions with brands on Facebook. In this study, we apply the uses and gratification theory proposed by Katz (1959) to develop a new typology of consumers based on consumer motivations to interact with brands on Facebook, and explore the type and intensity of these interactions. We identify five main motivations that might influence consumers’ interactions with a brand on Facebook: (1) social influence, (2) search for information, (3) entertainment, (4) trust and (5) reward. Building on these five motivations, a classification using clustering techniques reveals four different groups of consumers: (1) “brand detached”, (2) “brand profiteers”, (3) “brand companions” and (4) “brand reliants”. Our results provide valuable and applicable insights for social media marketing activities, which will assist brand managers to develop strategies for effectively reaching and influencing the most desirable groups of consumers.