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RAPOPORT H. F., FABBRI A., SEBASTIANI L., 2016. Olive Biology. In Rugini, E., Baldoni, L., Muleo, R., Sebastiani, L. (Eds.), “The Olive Genome”, pp. 13-26. Springer, Heidelberg.
No full textThe olive is a medium-sized evergreen tree, which integrates a unique set
of morphological and developmental characteristics suited to the relatively
dry, rustic conditions of its Mediterranean origin. Also particular to the
olive tree are its numerous small fruits, which are rich in oil that is highly
appreciated for both flavor and health benefits. The Olea europaea species
includes both wild and cultivated forms, and both a long period of
domestication and the perseverance of wild varieties provide a range of
morphological variation, as does the developmental plasticity of this
species. This chapter reviews the general growth and taxonomy of the
olive tree and describes its vegetative and reproductive morphology and
anatomy. Basic structural features of the trunk and branches, leaves, roots,
flowers, fruits, and seeds are described. Current research is indicated for
the structures discussed, and information provided regarding adaptive
significance, environmental influences, and genetically based variability
among cultivars or between wild and cultivated genotypes
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Il dibattito sulla sostenibilità del SSN
No full textIl progressivo invecchiamento della popolazione e i recenti tagli al fondo sanitario nazionale mettono in dubbio la sostenibilità futura del Servizio sanitario nazionale. L'adozione di nuovi modelli organizzativi e l'utilizzo delle tecnologie informatiche possono costituire una risposta a tali problemi
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Effect of different oxygen and Na+ levels on root radial anatomy in two Italian rice genotypes
No full textThe very peculiar radial anatomy of rice roots reflects the plant’s adaptation to semiaquatic growing conditions. The formation of aerenchyma, providing aeration of the root tissues by gas exchanges with the shoot, is constitutive in rice, although the extent and the precocity of its development may be affected by oxygen availability in the growth medium. The function of aerenchyma is implemented by strong barriers in the root peripheral layers which prevent radial oxygen loss. These barriers are the lignified sclerenchyma cell layer and, externally to this, the exodermis, which is reinforced, following two developmental stages, by the formation of Casparian bands (CBs) in radial and transverse cell walls and, later on, by the deposition of suberin lamellae to the inner surface of the anticlinal and tangential cell walls. These peripheral apoplastic barriers, as well as CBs and suberin lamellae deposited in the endodermis, confer selectivity in solute uptake, by impeding the apoplastic flow of water and solutes to the stele bypassing the trans-membrane transport. Since the apoplastic flow has been recognized as the main pathway by which Na+ enters rice shoot, the aptitude to modulate root porosity and development of apoplastic barriers in response to oxygen availability and to salt stress are expected to be crucial in conferring salt stress tolerance. Aim of the present work is to analyse, in rice, the effect of the presence of oxygen and/or NaCl on the formation of aerenchyma and on the development of both CBs and suberin lamellae in exodermis and endodermis. With this purpose, plants of Baldo and Vialone Nano, two Italian cultivars, were grown in hydroponic culture under a long-term (30 days) mildsalinity treatment (25 mM NaCl). These experiments were conducted in both aerobic and hypoxic conditions, miming the stagnant growing medium through the addition of a final concentration of 0.1% agar to the nutrient solution. A histological analysis was performed on adventitious roots by cutting cross sections at different distances from the tip. The development of aerenchyma along the root was detected by light microscopy observation under bright field; staining root sections with fluorochromes and dyes for suberin and lignin allowed to detect the deposition of CBs and suberin lamellae as well as the lignification of the
sclerenchyma layer. The results highlighted an effect of the presence of oxygen and/or NaCl in the growth medium on the histological development of rice root apoplastic barriers in terms of both
precocity and intensity
Salt stress response and effect of hypoxia on sodium uptake in two Italian rice cultivars
No full textSalt stress is one of the environmental constraints that affect crop cultivation worldwide, since more than 800 Mha of land throughout the world suffer from salinization problems. Soil salinity adversely damages plant growth in two ways: high concentrations of salts in the soil can reduce water uptake by plant roots, whereas high concentrations of salts within plants tissues may be toxic and alter the plant physiology. Plants species display different responses to high salinity conditions. Rice (Oryza sativa L.) is the cereal most sensitive to salt stress, although cultivars can differ in their response to salinity. European rice productivity is affected by abiotic and biotic stresses. In particular, due to scarce water availability and the rise in sea levels, there is a clear tendency toward salinization in the river deltas where rice is grown in Europe. In Italy, salt-affected soils in rice cultivation areas can be found in the eastern Po valley, along the Ionic and Tirrenic littorals, and in coastal areas of Sardinia. For this reason, the identification of rice cultivars tolerant to salt stress and the dissection of salt stress tolerance mechanisms are of high interest for rice breeding, also in Italy.
The aim of this work is to evaluate the salt stress response of two Italian cultivars, Baldo and Vialone Nano, as well as the effect of hypoxia on root anatomy and sodium uptake. A physiological analysis, which was conducted on plants grown in hydroponic culture under a long–term (30 days) mild-salinity treatment (25 mM NaCl), highlighted that in hypoxic conditions Baldo showed lower Na+ contents than Vialone Nano in both shoots and roots, whereas in aerated conditions the difference in the Na+ content between the two cultivars was observed only in shoots, suggesting a different effect of hypoxia on Na+ uptake by the roots between genotypes, as well as a different Na+ translocation to the shoot in more aerated conditions. A preliminary histological analysis of adventitious roots of plants grown in hypoxic conditions showed in Baldo the presence of Casparian bands and suberin lamellae closer to the root tip than in Vialone Nano, mainly in the endodermis, suggesting a different development of root apoplastic barriers, that may alter Na+ uptake by the root. A further experiment was conducted to study the Na+ translocation to the shoot in the two genotypes. Rice plants were grown in hydroponic culture under a short-term (24 h) high-salinity treatment (100 mM NaCl), and the Na+ level in root, culm and in the first, the second and the third leaf of plants was separately measured. The existence in the cultivar Baldo of a Na+ gradient among the plant organs was observed, with the lowest Na+ content in the youngest leaf. Differently, in Vialone Nano the youngest leaf displayed a higher amount of Na+ than the oldest one, thus confirming a different mechanism of Na+ translocation between the two genotypes. These results are in accordance with literature data, indicating that some rice genotypes are able to restrict Na+ translocation to the youngest leaves, thus preventing toxicity in active photosynthetic tissues, and to keep the highest levels of Na+ in the old leaves. Further investigations are in progress to confirm these data.
This work was supported by Progetto AGER, grant n° 2010-2369 (RISINNOVA - Integrated genetic and genomic approaches for new Italian rice breeding strategies)
Terzi molari ed ortodonzia: estrazione meditata o sistematica?
No full textGli autori in seguito ad una revisione sistematica della letteratura, si propongono di dare all’ortodontista come al chirurgo orale e maxillo – facciale delle indicazioni sulla necessità o meno di effettuare l’avulsione dei terzi molari in relazione alla terapia ortodontica
Terzi molari ed ortodonzia: estrazione meditata o sistematica?
No full textGli autori in seguito ad una revisione sistematica della letteratura, si propongono di dare all’ortodontista come al chirurgo orale e maxillo – facciale delle indicazioni sulla necessità o meno di effettuare l’avulsione dei terzi molari in relazione alla terapia ortodontica
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