This article examines the characteristics of surface dyslexia in a language (Italian) with high grapheme–phoneme correspondence. The reading performances of four boys are reported. The most pervasive reading symptom was severe slowness, which was associated in some, but not all, cases with reduced text comprehension. All four dyslexics performed at chance level on a task requiring comprehension of homophonous words (Study I). Vocal reaction times to single words were delayed with respect to the controls and showed a clear word length effect (Study II). However, vocal reaction times to pictorial stimuli were normal (Study III). Eye movement recordings taken during reading indicated an increased number and a reduced amplitude of rightward saccades and longer fixation durations (Study IV). A test of letter recognition in central and peripheral vision indicated that the reading deficit could not be explained in terms of an abnormal attentional “window,” as found in other cases of dyslexia (Study V). An analysis of the boys' cognitive skills (Study VI) indicated spared phonological awareness in three of four subjects; a severe deficit in rapid scanning of nonlinguistic stimuli was present in all of the subjects. Overall, these results indicate that parallel visual processing of words was impaired, and that the boys analyzed words sequentially, presumably through an orthographic–phonological conversion. This condition may be interpreted as surface dyslexia, even though the prominent characteristics of this syndrome are somewhat different in Italian than in other languages. In languages with “loose” relationships between graphemes and phonemes (e.g., English), when the phonological analysis of words is insufficient, a variety of errors is produced. In languages with considerably more regular grapheme–phoneme correspondence (e.g., Italian), the number of errors may be small since phonological reading is generally correct, and the most conspicuous symptom is slowness in reading.

The aim of this work is to elucidate the relationship between lignin main features and its behavior in natural rubber compounds, in particular focusing on thermal stability and mechanical properties. Five lignins obtained from different sources and through different extraction processes were characterized in terms of purity, sulfur content, molecular weight distribution (GPC), qualitative and quantitative functional group distribution (FTIR and 31 P-NMR). Then the lignins were incorporated in natural rubber by two different approaches, namely co-precipitation and dry-mixing. Thermal stability and mechanical properties of lignin/natural rubber blends were investigated in both masterbatches and vulcanized compounds. The Oxidation Induction Time (OIT) was used to determine the thermal stabilization of the lignin-NR masterbatchs, while tensile stress-strain properties of the compounds were evaluated after vulcanization. It was found that differences in the chemical and morphological characteristics of lignin influence its antioxidant and reinforcement capability. The addition of lignin to vulcanized compounds demonstrated the possibility to improve mechanical properties hypothetically through a tandem mechanism of protection and reinforcement.

Their physicochemical properties and relatively low cost make cellulose nanocrystals (CNCs) a potential candidate for future large-scale production in many fields including nanomedicine. Prior to a sustained and responsible development as theranostic agents, robust and reliable data concerning their safety, biocompatibility, and tissue distribution should be provided. In the present study, CNCs were extracted from Whatman filters functionalized with a fluorescent dye, and their interaction with living organisms has been thoroughly assessed. Our experimental evidence demonstrated that CNCs (1) are well tolerated by healthy mice after systemic injection; (2) are rapidly excreted, thus avoiding bioaccumulation in filter organs such as the kidneys and liver; (3) transiently migrate in bones; and (4) are able to penetrate in the cytoplasm of cancer cells without inducing material-related detrimental effects in terms of cell survival. Our results strongly suggest that the peculiar tropism to the bones is due to the chemical interaction between the Ca(2+) of the bone matrix and the active surface of negatively-charged CNCs. This feature, together with the ability to penetrate cancer cells, makes CNCs a potential nanodevice for theranostics in bone tumors.

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In this work, the possibility to conveniently exploit lignin as a functional additive for natural rubber was pursued following two strategies. The first was based on the fractionation of lignin: extraction with organic solvents is suitable to produce lignin fractions with better defined structural features, molecular weight distributions, and physicochemical properties. The second approach was based on the chemical modification of lignin in the attempt to overcome its poor affinity with the rubber: esterification with anhydrides was selected to modify relatively large samples of lignin at laboratory scale. The effectiveness of different modifications of lignin as a drop-in replacement for carbon black was evaluated analyzing the tensile mechanical properties of model elastomeric compounds. In addition, the behavior of the modified lignins was rationalized through Hansen solubility parameters predicted with the group-contribution method.

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