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Presence of sensor is relevant reality on all aspects of human life and based on the development of Internet of Things (IoT) in recent years the presence of sensors in our daily life is expected to continue increasing. The usability of a sensor in an application is derived from its technical performance but hardly driven from the package design to fit the system. Also cost down roadmap of MEMS based sensor is driving to study new solution to be able to use, for example, consumer market based material for automotive solutions. In this paper we will present an overview of different techniques based on FEM modeling used for virtual characterization, comparative and predictive design used for MEMS based sensor and microsystem modules. The target is to provide a toolbox for package designers at an early stage of product development targeting a design where package is functional part of the device.

Characeae is a taxonomically critical family. Taxonomical uncertainties inevitably affect its distributional data. The role of herbarium specimens, particularly types and original material, is crucial for unravelling taxonomical ‘knots’. Moreover, wet areas have undergone dramatic reduction and modification in the last century and historical herbarium specimens may represent basic documents for the reconstruction of former distributions. Some preliminary data from two different Italian Herbaria are here presented. The Herbarium Mediterraneum Panormitanum (PAL, the standard acronym according to the Index herbariorum, http://sweetgum.nybg.org/ ih) houses four folders of Characeae exsiccata. Two of them contain Italian material, the other two extra-Italian, mostly European material. Italian material totals 88 specimens, many of them collected in Sicily in 19th Century and often reviewed by Formiggini (1908). Many of these Sicilian collection localities are today deeply modified, but as later collections are quite rare, current knowledge on many taxa still relies on those very specimens, which should be carefully reviewed. As an example, one of the few known bisexual populations of Chara canescens Loisel., reported in Sicily at Pergusa Lake (one specimen is in PAL), could not be confirmed by recent exploration of the site. The Tropical Herbarium of Florence (FT) hosts 30 specimens of Characeae (data are available online: http://herbarium.univie.ac.at/database/search. php), most of them unidentified, but important because collected between the end of 19th and the first decades of 20th century in the Horn of Africa (the east African peninsula including Ethiopia, Somalia, and Eritrea, geographical core of FT collections). Present knowledge of the charophyte flora of this area is poor, and (as stated by Langangen 2015) “a more systematic survey will undoubtly produce interesting results”. - Formiggini L. 1908. Bullettino della Società Botanica Italiana 1908: 81-86. Langangen A. 2015. Acta Musei Nationalis Pragae, series B - Historia Naturalis 71(3-4): 239–248.

During the last year, the first two authors continued their survey of the scarcely known Characeae flora of the island of Sicily: plants were collected in different periods, habitats and areas of the island, and identifications – made on fresh material – were based mainly on Mouronval et al. (2015). We had the opportunity to include here some results deriving from the visit in Sicily made by Klaus van de Weyer in March 2018. Roman Romanov identified some specimens and revised some identifications. Data for Sicily are basically limited to more than one hundred years old reports; data for the national Flora have been completed with recent reports for Sardinia (cf. the work made by Ralf Becker). We present here the main results (in alphabetic order). 1) Chara baltica Bruzelius (new for Sicily) – Collected in different seasons in the lake Preola (Nature Reserve near Mazara), where it probably colonises most of the lake bottom, reaching a depth of ca. 2 m. 2) C. braunii C.C. Gmel. (new for Palermo province, new population of a rare species in Italy) – Collected in the small mountain ponds of Rebuttone. 3) C. canescens Loisel. (new population of a rare species in Italy): we found a new parthenogenetic population in the “Margi Milo” (Petrosino, Trapani province), where it grows together with C. cf. aspera Willd. 4) C. conimbrigensis A.G. Cunha (new for Sicily and Italy) – Collected in June-July in shallow mountain ponds, in the Nebrodi Mts, at about 1400 m a.s.l. It is different from the similar C. gymnophylla A. Braun mainly for its tylacanthous stem cortex. Waiting for further studies, we provisionally treat this taxon (as well as the following one) at the species rank. 5) C. oedophylla Feldmann (new for Sicily and Italy) – Collected in mid-April in temporary ponds (in the locus classicus of Isoetes todaroana Troia & Raimondo near Mazara del Vallo). The taxon is currently known in few sites in W-Mediterranean. 6) Nitella capillaris (Krock.) J. Groves & Bull.-Webst. (species not recently reported for Sicily and Italy) – Collected in the wetlands of Anguillara, near Calatafimi. 7) N. opaca (C. Agardh ex Bruzelius) C. Agardh (new for Sicily) – Collected in the small mountain ponds of Rebuttone (near Piana degli Albanesi) and Coda di Riccio (in the Nature Reserve of Ficuzza). 8) Tolypella salina Corill. (new for Sicily) – Collected in March in a single pond at Margi Milo near Petrosino (Klaus van de Weyer), it probably occurs also in other sites along the western coast of the island. - Mouronval JB, Baudouin S, Borel N, Soulié-Märsche I, Klesczewski M & Grillas P. 2015. Guide des Characées de France méditerranéenne. Office National de la Chasse et Faune Sauvage, Paris. 214 p.

New records to the Characean flora of Sicily are presented. Five species (Chara baltica, C. conimbrigensis, C. oedophylla, Nitella gracilis, Tolypella salina) are new to Sicily, two of them being also new to Italy (Chara conimbrigensis, C. oedophylla). Two species are confirmed for Sicily (Chara aspera, Nitella opaca), three (Chara braunii, C. canescens, Nitella capillaris) are rare taxa. The Characean flora of Sicily, updated with these records, currently includes 25 species, distributed in four genera: Chara (13 species), Nitella (eight species), Tolypella (three species) and Lamprothamnium (one species).

Only recently polymers with intrinsic conductive properties have been studied in relation to their incorporation into bioactive scaffolds for use in tissue engineering. The reason for this interest is that such scaffolds could electrically stimulate cells and thus regulate specific cellular activities, and by this means influence the process of regeneration of those tissues that respond to electrical impulses. In our work, macroporous hydrogels are developed with controlled pore morphology and conductive properties to enable sufficient cell signaling to supply events inherent to nerve regeneration. A hybrid material has been prepared by in situ precipitation of polyaniline (PANi) in polyethyleneglycol diacrylate (PEGDA) solution, followed by crosslinking via UV irradiation. A porous architecture, characterized by macropores from 136 μm to 158 μm in size, has been achieved by sodium chloride particle leaching. In this work, we demonstrate that PANi synthesis and hydrogel crosslinking combine to enable the design of materials with suitable conductive behaviour. The presence of PANi evidently increased the electrical conductivity of the hybrid material from (1.1 ± 0.5) × 10(-3) mS/cm with a PANi content of 3wt%. The hydrophilic nature of PANi also enhanced water retention/proton conductivity by more than one order of magnitude. In vitro studies confirmed that 3 wt% PANi also improve the biological response of PC12 and hMSC cells. Hybrid PANi/PEGDA macroporous hydrogels supplement new functionalities in terms of morphological and conductive properties, both of which are essential prerequisites to drive nerve cells in regenerative processes.

Proton conductivity of innovative ionomeric membranes based on partially sulfonated syndiotactic polystyrene (SsPS) was investigated. The membranes were prepared with various levels of sulfonation by chlorosulfonic reaction on sPS films, in its clathrate form, obtained by solution-casting. The actual sulfonation degree of sPS membranes was evaluated by elemental analysis and their proton conductivity was measured using a galvanostatic four-points-probe electrochemical impedance spectroscopy technique. The dependence of conductivity on the level of sulfonation, hydration condition, and temperature was studied. At higher sulfonation degrees, SsPS membranes showed the best performance in vapor phase at 100% RH. In particular, the best SsPS membrane with sulfonation degree about 26 mol% exhibited conductivity equal to 8.8 × 10−2 Ω−1 cm−1 at 31.5 °C. This property is stable during time and increases with temperature. For the membranes with the highest degree of sulfonation, we measured a methanol permeability ...

Today’s lithographic techniques for carving silicon into circuit patterns are unable to achieve the future target of the semiconductor industry of fabricating ultrahigh density memory devices made of memory cells just few tens of nanometers apart. Methods of extending these approaches to large-scale, high-density circuitry are largely undeveloped. Between emerging self-assembly bottom-up methods for advanced fabrication of electronic devices based on organic matrices, nanocomposites formed by a conducting phase (e.g. metal nanoparticles) dispersed in a polymeric matrix have attracted considerable attention, because these materials might be used as an active layer in almost all kinds of organic electronic devices. In this paper a different approach for the fabrication of advanced electronic devices is suggested, based on the combination of two concepts: the use of organic materials as active layers that guarantees simplified manufacturing process yielding low-cost, flexible, and light-weight devices, and the use of self-assembly of block copolymers (BCPs) that allows building nanostructures from the bottom up using individual macromolecules. The ordered cylindrical self-assembled nanostructure formed from PS- b -PMMA is used as host for selectively sequestering gold nanoparticles. The ordered distribution of the functional particles is guided by the ordering of the host matrix and allows arising other numerous possible applications that depend on the nanospecific properties of the sequestered components and the intrinsic flexibility of the polymeric matrix. The BCP structure has many considerable advantages in terms of low material consumptions and reduced operating voltages for producing high bistability effects in well ordered nanostructures. Moreover, the excellent results we achieved in terms of electronic performances and the high potential opened by this nanotechnology toward the development of innovative materials open the way toward the realization of novel organic devices containing different physical types of functionalized nanoparticles (e.g. oxides, superconductors, etc.), and the investigation of their fundamental properties.

A helical crystalline modification of syndiotactic polystyrene (sPS), the δ-form, was employed to prepare solution-cast films selectively sulfonated on the surface. This result was achieved because of the unusual transport characteristics of the δ-form, exhibiting comparatively large diffusivity and solubility values for low-molecular weight compounds such as chloroform, which can be effectively used as a carrier solvent. The results of sulfonation of the δ-form are compared with those obtained with a trans-planar crystalline modification of sPS (β-form). The latter was found unsuitable for selective surface modification. The analysis of the sulfonated films was carried out by FT-Raman and confocal-Raman spectroscopy. The first technique was used to investigate the average composition of the samples in terms of sulfonation degree and crystalline structure. It also allowed us to construct calibration curves to be used in connection with the confocal-Raman data. The latter technique was employed to generate images with spectroscopic contrast and to quantitatively characterize the depth-profiles of the investigated films.