| 1. |
- Chigrinova, Ekaterina, et al.
(author)
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Two main genetic pathways lead to the transformation of chronic lymphocytic leukemia to Richter syndrome
- 2013
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In: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 122:15, s. 2673-2682
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Journal article (peer-reviewed)abstract
- Richter syndrome (RS) occurs in up to 15% of patients with chronic lymphocytic leukemia (CLL). Although RS, usually represented by the histologic transformation to a diffuse large B-cell lymphoma (DLBCL), is associated with a very poor outcome, especially when clonally related to the preexisting CLL, the mechanisms leading to RS have not been clarified. To better understand the pathogenesis of RS, we analyzed a series of cases including 59 RS, 28 CLL phase of RS, 315 CLL, and 127 de novo DLBCL. RS demonstrated a genomic complexity intermediate between CLL and DLBCL. Cell-cycle deregulation via inactivation of TP53 and of CDKN2A was a main mechanism in the histologic transformation from CLL phase, being present in approximately one half of the cases, and affected the outcome of the RS patients. A second major subgroup was characterized by the presence of trisomy 12 and comprised one third of the cases. Although RS shared some of the lesions seen in de novo DLBCL, its genomic profile was clearly separate. The CLL phase preceding RS had not a generalized increase in genomic complexity compared with untransformed CLL, but it presented clear differences in the frequency of specific genetic lesions.
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| 2. |
- Ferruti, Federica, et al.
(author)
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Recombinatorial approach for the formation of surface-functionalised alkaline-stable lignin nanoparticles and adhesives
- 2023
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In: Green Chemistry. - : Royal Society of Chemistry (RSC). - 1463-9262 .- 1463-9270. ; 25:2, s. 639-649
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Journal article (peer-reviewed)abstract
- Lignin nanoparticles (LNPs) are considered as intriguing green, renewable alternatives to fossil-based nanomaterials. However, the predisposition of LNPs to dissolve under alkaline conditions makes covalent surface functionalisation in the dispersion state difficult and limits applications demanding morphological stability under challenging pH conditions. Mechanistic studies suggest that during the formation of LNPs by nanoprecipitation the higher molecular weight fractions of lignin likely start precipitating first, while the low molecular weight fractions tend to deposit later and thus locate on the outer shell. Capitalising this aggregation pattern, the present work presents a strategy to prepare surface-functionalised LNPs that can find applications as adhesives and alkaline stable LNPs. The entire process is based on a single-step solvent fractionation of lignin using either ethanol or ethyl acetate, subsequent functionalisation of selected fractions with epichlorohydrin, and recombination according to the original mass proportions in line with the so-called zero waste principle. Aqueous colloidal dispersions of lignins were synthesised by nanoprecipitation of epoxidised low molecular weight (MW) fractions combined with the corresponding unmodified high MW ones, and vice versa. Upon thermal treatment, LNPs containing the epoxidised insoluble fraction underwent intraparticle crosslinking, proving dimensional stability at pH 12. Conversely, LNPs including epoxidised solvent-soluble fractions resulted in interparticle crosslinking upon heating, which confirmed the surface localisation of such low MW fractions. The latter system was exploited to develop green LNP-based adhesives for aminated glass with lap shear strength outperforming prior adhesive systems based on lignin particles.
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| 3. |
- Milan, Riccardo, et al.
(author)
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Dye-sensitized solar cells based on a push-pull zinc phthalocyanine bearing diphenylamine donor groups : computational predictions face experimental reality
- 2017
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In: Scientific Reports. - : Nature Publishing Group. - 2045-2322. ; 7
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Journal article (peer-reviewed)abstract
- Computational studies have suggested that the integration of secondary amine as donor groups in the structure of unsymmetrical zinc phthalocyanine (ZnPc) should have positive effects on photovoltaic performance, once the molecule is integrated as light harvester in dye sensitized solar cells (DSSCs). Aiming at obtaining experimental confirmation, we synthesized a peripherally substituted push-pull ZnPc bearing three electron donating diphenylamine substituents and a carboxylic acid anchoring group and integrated it as sensitizer in TiO2-based DSSCs. Detailed functional characterization of solar energy converting devices resulted in ruling out the original hypothesis. The causes of this discrepancy have been highlighted, leading to a better understanding of the conditions for an effective design of push-pull diarylamino substituted ZnPcs for DSSCs.
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| 4. |
- Milan, Riccardo, et al.
(author)
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Zinc phthalocyanines as light harvesters for SnO2-based solar cells : a case study
- 2020
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In: Scientific Reports. - : Springer Nature. - 2045-2322. ; 10
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Journal article (peer-reviewed)abstract
- SnO2 nanoparticles have been synthesized and used as electron transport material (ETM) in dye sensitized solar cells (DSSCs), featuring two peripherally substituted push-pull zinc phthalocyanines (ZnPcs) bearing electron donating diphenylamine substituents and carboxylic acid anchoring groups as light harvesters. These complexes were designed on the base of previous computational studies suggesting that the integration of secondary amines as donor groups in the structure of unsymmetrical ZnPcs might enhance photovoltaics performances of DSSCs. In the case of TiO2-based devices, this hypothesis has been recently questioned by experimental results. Herein we show that the same holds for SnO2, despite the optimal matching of the optoelectronic characteristics of the synthesized nanoparticles and diphenylamino-substituted ZnPcs, thus confirming that other parameters heavily affect the solar cells performances and should be carefully taken into account when designing materials for photovoltaic applications.
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| 5. |
- Scribner, Emily D., et al.
(author)
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Magnesio-lucchesiite, CaMg3Al6(Si6O18)(BO3)3(OH)3O, a new species of the tourmaline supergroup
- 2021
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In: American Mineralogist. - : Mineralogical Society of America. - 0003-004X .- 1945-3027. ; 106:6, s. 862-871
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Journal article (peer-reviewed)abstract
- Magnesio-lucchesiite, ideally CaMg3Al6(Si6O18)(BO3)3(OH)3O, is a new mineral species of the tourmaline supergroup. The holotype material was discovered within a lamprophyre dike that cross-cuts tourmaline-rich metapelites within the exocontact of the O’Grady Batholith, Northwest Territories (Canada). Two additional samples were found at San Piero in Campo, Elba Island, Tuscany (Italy) in hydrothermal veins embedded in meta-serpentinites within the contact aureole of the Monte Capanne intrusion. The studied crystals of magnesio-lucchesiite are black in a hand sample with vitreous luster, conchoidal fracture, an estimated hardness of 7–8, and a calculated density of 3.168 (Canada) and 3.175 g/cm3 (Italy). In plane-polarized light, magnesio-lucchesiite is pleochroic (O = dark brown, E = colorless) and uniaxial (–); its refractive index values are nω = 1.668(3) and nε = 1.644(3) (Canada), and nω = 1.665(5) and nε = 1.645(5) (Italy). Magnesio-lucchesiite is trigonal, space group R3m, Z = 3, with a = 15.9910(3) Å, c = 7.2224(2) Å, V = 1599.42(7) Å3 (Canada) and with a = 15.9270(10) Å, c = 7.1270(5) Å, V = 1565.7(2) Å3 (Italy, sample 1). The crystal structure of magnesio-lucchesiite was refined to R1 = 3.06% using 2953 reflections with Fo > 4σ(Fo) (Canadian sample; 1.96% / 1225 for the Italian sample) The Canadian (holotype) sample has the ordered empirical formula X(Ca0.60Na0.39K0.01)Σ1.00Y(Mg2.02Fe2+0.62Fe3+0.09Ti0.25V0.01Cr0.01)Σ3.00Z(Al5.31Fe3+0.69)Σ6.00[T(Si5.98Al0.02)Σ6.00O18(BO3)3V[(OH)2.59O0.41]Σ3.00W(O0.78F0.22)Σ1.00. The Italian (co-type) material shows a wider chemical variability, with two different samples from the same locality having ordered chemical formulas: X(Ca0.88Na0.12)Σ1.00Y(Mg1.45Fe2+0.40Al0.79Fe3+0.36)Σ3.00ZAl6[T(Si5.05Al0.95)Σ6.00O18](BO3)3V[(OH)2.90O0.10]Σ3.00W(O0.98F0.02)Σ1.00(sample 1) and X(Ca0.71Na0.21o0.08)Σ1.00Y(Mg2.49Fe2+0.41Ti0.10)Σ3.00Z(Al5.44Fe3+0.46Mg0.09V0.01)Σ6.00[T(Si5.87Al0.13)Σ6.00O18](BO3)3V(OH)3W[O0.61(OH)0.39]Σ1.00 (sample 2). Magnesio-lucchesiite is an oxy-species belonging to the calcic group of the tourmaline supergroup. It is related to lucchesiite by the homovalent substitution YFe ↔ YMg, and to feruvite by the homovalent and heterovalent substitutions YFe ↔ YMg and ZAl3+ + WO2– ↔ ZMg2+ + W(OH)1–. The new mineral was approved by the International Mineralogical Association Commission on New Minerals, Nomenclature and Classification (IMA 2019-025). Occurrences of magnesio-lucchesiite show that its presence is not restricted to replacement of mafic minerals only; it may also form in metacarbonate rocks by fluctuations of F and Al during crystallization of common uvitic tourmaline. High miscibility with other tourmaline end-members indicates the large petrogenetic potential of magnesio-lucchesiite in Mg,Al-rich calc-silicate rocks, as well as contact-metamorphic and metasomatic rocks.
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