1,060 research outputs found
A conspectus of and key to greek isoetes (Isoetaceae), based on a reassessment of haussknecht\u2019s gatherings of 1885
The three Isoetes species recorded from Thessalia (Thessaly) in N Greece by Haussknecht, in 1899, under the names I. setacea, I. heldreichii, and I. phrygia, were reassessed using megaspore and microspore ornamentation in addition to macromorphological features. \u201cIsoetes setacea\u201d is not the SW European I. delilei to which the name I. setacea was generally misapplied, nor \u201cI. echinospora\u201d as it has been called due to a misunderstanding, but a so far undescribed species here named I. haussknechtii; it has not been found again in Haussknecht\u2019s locality but has recently turned up in Peloponnisos and the E Aegean Islands. I. heldreichii, described from Haussknecht\u2019s gathering, is apparently extinct. The record of I. phrygia was based on misidentified I. gymnocarpa. Even so, contrary to prevailing opinion, Haussknecht was justified in raising Boissier\u2019s I. histrix var. phrygia to specific rank; genuine I. phrygia has recently been discovered in Kriti (Crete). The inventory of Greek Isoetes now comprises seven species, of which I. phrygia and I. todaroana are newly recorded here. Greek specimens studied are cited for all of them, and a key for their identification is presented. The names I. heldreichii and I. phrygia are typified
Independent tuning of acoustic and mechanical properties of phantoms for biomedical applications of ultrasound
In this work the preparation of tissue mimicking materials (TMMs) with independently tunable acoustic and elastic properties is reported. Although a large number of hydrogel, synthetic polymer, polysaccharides or other natural based materials have been proposed and used for the realization of TMMs, both for diagnostic and therapeutic applications of ultrasounds, up to today, simulation of acoustic properties was often performed using solid particles, reducing dramatically the transparency and inevitably affecting the homogeneity and the elastic properties of the TMM. By means of concentrated salts solutions and different polysaccharides, an easy method to prepare these TMMs have been developed. This approach would lead to obtain homogenous TMMs with Young modulus ranging over 3 orders of magnitude, i.e. from 2 to 1500 kPa, with independently tunable attenuation properties. An accurate mechanical and acoustic characterization of these TMMs have been performed. Finally, by means of a preliminary trials on protein denaturation induced by a high focused ultrasound transducer in a transparent TMMs with different attenuation values, the mechanism underlying on the formation and propagation of lesion has been investigated. Obtained results suggest that this 'chemical' approach would strongly support in vitro investigations on the open issues related to diagnostic and therapeutic application of ultrasounds
Nonlinear interplay of Alfven instabilities and energetic particles in tokamaks
The confinement of energetic particles (EP) is crucial for an efficient
heating of tokamak plasmas. Plasma instabilities such as Alfven Eigenmodes (AE)
can redistribute the EP population making the plasma heating less effective,
and leading to additional loads on the walls. The nonlinear dynamics of
toroidicity induced AE (TAE) is investigated by means of the global gyrokinetic
particle-in-cell code ORB5, within the NEMORB project. The nonperturbative
nonlinear interplay of TAEs and EP due to the wave-particle nonlinearity is
studied. In particular, we focus on the nonlinear modification of the
frequency, growth rate and radial structure of the TAE, depending on the
evolution of the EP distribution in phase space. For the ITPA benchmark case,
we find that the frequency increases when the growth rate decreases, and the
mode shrinks radially. This nonlinear evolution is found to be correctly
reproduced by means of a quasilinear model, namely a model where the linear
effects of the nonlinearly modified EP distribution function are retained.Comment: Submitted to Plasma Phys. Control. Fusio
On the presence, distribution and conservation status of Lycopodium lagopus (Lycopodiaceae) in Italy
During our work on the Lycopodiaceae account for the upcoming Flora Critica d\u2019Italia (1, 2), we assessed and accepted the presence in Italy of Lycopodium lagopus (Laest. ex Hartm.) Zinserl. ex Kuzen. = L. clavatum subsp. monostachyon (Grev. & Hook.) Selander (2).
Already reported by Fiori (3) as L. clavatum f. monostachyum Desv., its presence in Italy was more recently confirmed by Tribsch & Sch\uf6nswetter (4) and accepted in some subsequent regional works (e.g. 5, 6), but the taxon is not recognized as distinct in the last national checklist of vascular plants (7).
Lycopodium lagopus has an arctic-alpine distribution in America and Eurasia (8, 9). Initially described as a variety of L. clavatum L., the taxon was later raised to subspecific (e.g. 10, 11) and specific rank (8, 9). In view of its largely sympatric occurrence with L. clavatum in the Alps, and of the apparent absence of intermediate populations or individuals, we prefer to treat L. lagopus as a separate species.
The main characters distinguishing L. lagopus from L. clavatum are the number of strobili (usually 1, rarely 2), and especially their being sessile or subsessile on a 0-2 cm long \u201cpeduncle\u201d.
In the Italian Alps it usually occurs at >1800 m a.s.l. As a result of our revision of specimens in several Italian herbaria, this clubmoss, formerly known only from Trentino - Alto Adige and Lombardy, is here reported for the first time for Piedmont on the basis of two specimens collected by Carestia in Valsesia in 1870 and preserved in TO. The presence in Friuli - Venezia Giulia (reported in 6 on the basis of a posthumous work of Gortani) is not confirmed: a specimen collected by Gortani in 1908 and preserved in MFU under \u201cL. clavatum f. monostachyum Desv.\u201d is referable to L. clavatum. On the other hand, in view of the specie\u2019s ecology and confirmed distribution, one may reasonably expect that it is to be found, additionally, in Val d\u2019Aosta and Veneto.
Lycopodium species in Europe have experienced a decline in abundance in a general way, partly due to their being collected and overexploited, and for this reason they have all been included in Annex V of the Habitats Directive 92/43/CEE. Lycopodium clavatum in particular, whose decline in Italy is confirmed by several authors (e.g., 6), is also included in Annex D of the Council Regulation (EC) No 338/97 on the protection of species of wild fauna and flora by regulation their trade.
It is therefore urgent to define the current distribution and conservation status of L. lagopus in Italy, in order to plan possible conservation measures. We hope that its inclusion (as L. clavatum subsp. monostachyum) in the most recent Red List of Italian Flora (12), even if only as DD (Data Deficient), and the contribution here presented may stimulate the study of this species in Italy.
This study is part of the \u201cFlora Critica d\u2019Italia\u201d project and as such was funded by the Societ\ue0 Botanica Italiana onlus, the Fondazione per la Flora Italiana, and the International Foundation Pro Herbario Mediterraneo.
1) L. Pignotti (ed) (2006) Progetto per una Flora critica dell\u2019Italia. Societ\ue0 Botanica Italiana, Firenze
2) A. Troia, W. Greuter (2013) Proceedings of XIV OPTIMA Meeting, Palermo, 9-15 September 2013, p. 151
3) A. Fiori (1943) Flora Italica Cryptogama, pars V: Pteridophyta. Tipografia Mariano Ricci, Firenze
4) A. Tribsch, Sch\uf6nswetter P. (1999) Verh. Zool.-Bot. Ges.
6sterreich, 136, 235-248
5) D. Aeschimann, K. Lauber, D.M. Moser, J.P. Theurillat (2004) Flora Alpina. Haupt Verlag, Bern
6) E. Bona (ed), F. Martini, H. Niklfeld, F. Prosser (2005) Atlante corologico delle Pteridofite nell\u2019Italia nordorientale. Distribution Atlas of the Pteridophytes of North-Eastern Italy. Museo Civico di Rovereto, Edizioni Osiride
7) F. Conti, G. Abbate, A. Alessandrini, C. Blasi (eds) (2005) An annotated checklist of the Italian vascular flora. Palombi Editori, Roma
8) W.H. Wagner, J. Beitel (1993) Lycopodiaceae. In: Flora of North America Editorial Committee (eds) Flora of North America Vol. 2 Pteridophytes & Gymnosperms. Oxford University Press, New York, pp. 18-37
9) F.J. Rumsey (2007) Watsonia, 26, 477-480
10) W. Rothmaler, A.C. Jermy (1993) Lycopodium L. In: T.G. Tutin et al. (eds), Flora europaea vol. 1, ed. 2. Cambridge, p. 4
11) I. Kukkonen (2000) Lycopodiaceae. In: B. Jonsell (ed) Flora Nordica 1. The Bergius Foundation, Stockholm, pp. 1-13
12) G. Rossi et al. (2013) Lista Rossa della Flora Italiana. 1. Policy Species e altre specie minacciate. Comitato Italiano IUCN e Ministero dell\u2019Ambiente e delle Tutela del Territorio e del Mar
Aquatic Macrophytes Occurrence in Mediterranean Farm Ponds: Preliminary Investigations in North-Western Sicily (Italy)
Mediterranean wetlands are severely affected by habitat degradation and related loss of
biodiversity. In this scenario, the wide number of artificial farm ponds can play a significant role in the biodiversity conservation of aquatic flora. In the present contribution we show the preliminary results of a study on Mediterranean farm ponds of north-western Sicily (Italy), aimed to investigating the environmental factors linked to the occurrence of submerged macrophytes (vascular plants and charophytes). We studied the aquatic flora of 30 ponds and determined the chemical and isotopic composition of their water bodies on a subset of the most representative 10 sites. Results show that (1) farm ponds host few but interesting species, such as Potamogeton pusillus considered threatened at regional level; (2) Chara vulgaris, C. globularis and P. pusillus behave as disturbance-tolerant species, occurring both in nitrates-poor and nitrates-rich waters, whereas Stuckenia pectinata and Zannichellia palustris occur only in nitrates-poor waters. Although farm ponds are artificial and relatively poor habitats, these environments seem to be important for the aquatic flora and for the conservation of the local biodiversity, and can give useful information for the use of macrophytes as ioindicators in the Mediterranean area
Life on islands. 1. Biodiversity in Sicily and surrounding islands. Studies dedicated to Bruno Massa
Concomitant infections with canine parvovirus type 2 and intracellular tick-borne pathogens in two puppy dogs
In this report the concomitant infection with canine parvovirus type 2 (CPV-2), Hepatozoon canis and Ehrlichia canis in two puppy dogs from Southern Italy is described. Dogs were referred to a veterinary university hospital for the acute onset of lethargy and gastrointestinal signs. A complete clinical and clinicopathological evaluation was carried out and the multiple infection was confirmed by microscopic detection of inclusion bodies in peripheral blood smear, rapid immunoenzymatic tests, indirect fluorescent antibody tests, and molecular assays. Sequence analysis revealed that the CPV-2 identified belonged to the 2c variant and had amino acid residues in the predicted VP2 protein typical of "Asian-like" strains widespread in Asia and occasionally reported in Romania, Nigeria and Italy, particularly in the region of Sicily. Numerous monocytes were infected by both H. canis gamonts and E. canis morulae, suggesting that this co-infection is not accidental and that E. canis preferably infects those cells parasitized by H. canis. The clinical presentation of these animals was severe but supportive cares associated with early etiological therapy allowed a good prognosis. Movement of puppies from geographic areas where vector-borne pathogens are endemic must be carefully evaluated and core vaccinations and ectoparasite prevention treatments must be rigorously adopted
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