Tailoring self-assembly and optoelectronic properties of organic semiconductors via macromolecular engineering

Conjugated polymers and small molecules are a promising class of semiconducting materials for application in macroelectronic and energy conversion devices. The development of high performance devices employing this class of semicrystalline materials ultimately depends on the precise control of crystalline domain size, orientation and connectivity due to the complex nature of their molecular interactions and chemical structure. It is there-fore of paramount importance to control self-assembly processes of Ï-conjugated molecules and polymers into functional microstructures over a wide set of length scales suitable for device optimal operation. In the present thesis, we investigated the effect that novel materials design criteria have on the control of the active layer morphology and long-term stability in organic field effect transistors and bulk heterojunction solar cells. A first strategy to reduce microstructure complexity in semiconducting polymer thin-films is to separate the contributions to morphology and charge transport resulting from different polymer molecular weights. Combined morphological and electronical characterization revealed a high degree of isotropy in charge transport mechanisms in semicrystalline and poorly aggregating conjugated systems as a result of the broad variety of self-assembled microstructures observed at different molecular weights. Next, we designed and synthesized a new class of semi-conducting materials based on a flexible linker concept. Initially, we showed the successful preparation and purification of a prototype in a class of semiconducting polymer that allows independent control over the conjugated segment length and overall chain length by covalently linking low-MW conjugated segments with flexible aliphatic linkers. Our flexibly linked polymeric material exhibited improved thin-film formation compared to the low-MW starting polymer and unique thermal properties. Importantly, our linking strategy had a clear effect on the chain self-assembly and allowed structural control between distinct thin film morphologies without altering the chain length. Next we extended the flexible linker design motif to small molecule derivatives that are employed in high performance bulk heterojunction solar cells. In this study we showed, that active layer degradation under continuous thermal stress can be inhibited by the formation of a more robust thin film microstructure with the additive present. Finally, the efficient functionalization of a series of polymeric blocks was successfully used to synthetize a new class of alternated multi-block copolymers. The facile nature of the synthetic procedure ena-bles high degree of polymerization and offers the possibility to include a large number of semiconducting polymers in block copolymer architectures. Ultimately, when our alternating multi-block copolymers are solution processed in thin films, a relatively high degree of self-assembly and micro-domains phase separation is ob-served at length scale ideal for well-ordered heterojunction needed to improve solar cells efficiency

Skin perfusion of hands is associated with parasympathetic activity in systemic sclerosis

Changes in the activity or responsiveness of neuroendothelial mecha-nisms may trigger vascular injury with im-balance of angiogenesi

Adjunctive treatment and BoNT-A for post-stroke spasticity: are we really focusing on the patient-centered goals?

[no abstract available

Anatomical landmarks for ultrasound‐guided rectus femoris diagnostic nerve block in post‐stroke spasticity

Introduction/Purpose To determine the location of the rectus femoris (RF) motor branch nerve, as well as its coordinates with reference to anatomical and ultrasound landmarks. Methods Thirty chronic stroke patients with stiff knee gait (SKG) and RF hyperactivity were included. The motor nerve branch to the RF muscle was identified medially to the vertical line from anterior superior iliac spine and the midpoint of the superior margin of the patella (line AP) and vertically to the horizontal line from the femoral pulse and its intersection point with the line AP (line F). The point of the motor branch (M) was located with ultrasound, and nerve depth and subcutaneous tissue thickness (ST) were calculated. Results The coordinates of the motor branch to the RF were 2.82 (0.47) cm medially to the line AP and 4.61 (0.83) cm vertically to the line F. Nerve depth and subcutaneous tissue thickness were 2.71 (0.62) cm and 1.12 (0.75) cm, respectively. Conclusion The use of specific coordinates may increase clinicians' confidence when performing RF motor nerve block. This could lead to better decision-making when assessing SKG in chronic stroke patients

Spatial behaviour of yellow-necked wood mouse Apodemus flavicollis in two sub-Mediterranean oak coppice stands

Strong mutual relationships exist between rodents and ecosystems. By modifying the structure and functioning of ecosystems, human activity can affect rodent behaviour and ecology. The yellow-necked mouse Apodemus flavicollis is widespread in Europe and its spatial ecology has been studied in various habitats, but studies are lacking for Mediterranean forests often altered by forest management practices. We investigated the spatial behaviour of A. flavicollis in a sub-Mediterranean deciduous oak forest of central Italy subject to forest management. We radio-tracked 27 individuals in two different coppice stands, i.e. a recently cut area and a high forest, differing in terms of species-specific habitat quality and rodent population density. We analysed the size of home ranges in relation to habitat type and sex. Our results revealed that home range and core area size did not differ between habitat types or sexes. The spatial behaviour of A. flavicollis thus did not appear to be influenced by population density and habitat quality. The lack of sex-related differences confirms the current knowledge on the species’ spatial ecology. Our findings provide the first useful information on the spatial behaviour of A. flavicollis in sub-Mediterranean deciduous oak forests, whose ecological processes may be markedly influenced by this key-species at several trophic levels.acceptedVersio

Dataset of analyzes performed to determine the level and timing of selected organic pollutants’ inputs in sediments of the Lake of Cavazzo (Italy)

This data article presents the dataset collected for selected organic pollutants in the framework of a larger research project aimed at assessing the effects of different environmental stressors (natural and anthropogenic) in sediments of the Lake of Cavazzo, a basin of glacial origin located in a seismically active region of the Italian Eastern Alps. Information relative to sampling strategy and operations, location of sampling sites, sedimentary chronological benchmarks, and profiles of RGB (Red-Green-Blue) color code determined from high resolution photos taken at cores CAV-04 and CAV-06 are reported, together with analytical data for 15 polycyclic aromatic hydrocarbons, 21 polychlorinated biphenyls’ congeners (including the non-Aroclor CB-11), 14 polybrominated diphenyl ethers’ congeners, and 22 organochlorine pesticides, whose concentrations were determined by Gas Chromatography coupled both to Low-Resolution and High-Resolution Mass Spectrometry. Interpretation of this dataset is fully discussed in the companion article by Pizzini et al. (2022) and relys on the multi-proxy analysis of sediment samples presented in Polonia et al. (2021) that highlighted lake stratigraphy and major changes occurring at a decadal scale since the 1950s

An atlas of Mediterranean seismicity

We present a description of the characteristics of the seismic deformation occurring in the Alpine Mediterranean Belt, and outline its association with tectonic and geologic features. We map seismic activity using several catalogues. Hypocentral data are retrieved from the Catalog of the International Seismological Center, the most comprehensive compilation of global data. Earthquake size and source geometry are instead evaluated from catalogs of earthquake mechanisms. These include seismic moment tensor catalogs (mainly the Harvard CMT Catalog, the Euro-Mediterranean Regional Centroid-Moment Tensors – RCMT Catalog and the regional moment tensor determination in the European-Mediterranean area – ETH Catalog) and a recent extensive compilation of solutions available in literature (EMMA) that provides consistency-controlled fault-plane solutions where mechanisms based on waveform fitting are missing. The study area follows the Africa-Eurasia margin from the Central Atlantic to Iran, and it has been divided into several provinces for the sake of presentation and graphic purposes. For each province, a brief geologic and tectonic description complements the outline of the pattern of seismicity, illustrated by several maps. Focal mechanisms are also grouped together to yield average mechanisms and enable synoptic views. A comprehensive bibliography is referenced. A CD-ROM accompanying this issue contains, besides maps, figures and results of local comparisons and summation of moment tensors with easy access via sensible maps, also an updated version of the EMMA focal mechanism database. Rather than an attempt at presenting a comprehensive seismotectonic model of the Mediterranean, this contribution aims to offer a panoramic view of the active tectonics as imaged by seismicity and focal mechanisms. Its scope may be seen as similar to that of an atlas, as a broad reference and a support for more specific studies

Chameleonic dilaton, nonequivalent frames, and the cosmological constant problem in quantum string theory

The chameleonic behaviour of the String theory dilaton is suggested. Some of the possible consequences of the chameleonic string dilaton are analyzed in detail. In particular, (1) we suggest a new stringy solution to the cosmological constant problem and (2) we point out the non-equivalence of different conformal frames at the quantum level. In order to obtain these results, we start taking into account the (strong coupling) string loop expansion in the string frame (S-frame), therefore the so-called form factors are present in the effective action. The correct Dark Energy scale is recovered in the Einstein frame (E-frame) without unnatural fine-tunings and this result is robust against all quantum corrections, granted that we assume a proper structure of the S-frame form factors in the strong coupling regime. At this stage, the possibility still exists that a certain amount of fine-tuning may be required to satisfy some phenomenological constraints. Moreover in the E-frame, in our proposal, all the interactions are switched off on cosmological length scales (i.e. the theory is IR-free), while higher derivative gravitational terms might be present locally (on short distances) and it remains to be seen whether these facts clash with phenomenology. A detailed phenomenological analysis is definitely necessary to clarify these points

The 2015 version of the Italian Parametric Earthquake Catalogue (CPTI15)

The Italian Parametric Earthquake Catalogue (CPTI) represents the most extensive and reliable source of parameters for earthquakes in Italy and surrounding areas. Since its first introduction in 1999, CPTI benefits from the results of the 30-years-long Italian tradition in historical earthquake research that, still today, keeps on providing a wealth of studies and macroseismic data. Such data have been collected, homogenized and made available through several releases of the related macroseismic database (DBMI). In 2016, the fourth release of CPTI and DBMI, has been finalized. They provide the most advanced and updated sets of macroseismic and instrumental data and parameters, and cover the time-span 1000-2014 with earthquakes with maximum intensity I ≥ 5 or magnitude Mw ≥ 4.0. The catalogue lists 4574 events, 70% of which accompa- nied by intensity data points (about 125’000 as a whole). Macroseismic data derive from 185 studies, 54 of them are new with respect to the previous version CPTI11. Parameters related to historical earthquakes are completely re-assessed, and magnitudes from macroseismic data are derived with new intensity-to-Mw relationships. Such relationships are based on the same dataset that contributes updated instrumental magnitudes to the catalogue. Either Mw from moment tensor solutions or proxies calculated with new published conversion relationship are considered. If available, both macroseismic and instrumental parameters are provided, together with a set of “preferred ones”, which consist of a selection between the macroseismic and the instrumental epicentres, and the weighted average of the macroseismic and instrumental magnitudes.PublishedTrieste, Italy3T. Storia Sismica4T. Sismologia, geofisica e geologia per l'ingegneria sismica4IT. Banche dat

Power-Law Time Distribution of Large Earthquakes

We study the statistical properties of time distribution of seimicity in California by means of a new method of analysis, the Diffusion Entropy. We find that the distribution of time intervals between a large earthquake (the main shock of a given seismic sequence) and the next one does not obey Poisson statistics, as assumed by the current models. We prove that this distribution is an inverse power law with an exponent $\mu=2.06 \pm 0.01$. We propose the Long-Range model, reproducing the main properties of the diffusion entropy and describing the seismic triggering mechanisms induced by large earthquakes.Comment: 4 pages, 3 figures. Revised version accepted for publication. Typos corrected, more detailed discussion on the method used, refs added. Phys. Rev. Lett. (2003) in pres