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L’Italia detiene uno dei tassi di natalità più bassi al mondo e infertilità e sterilità stanno diventando realtà sempre più diffuse. Dopo diversi tentativi infruttuosi, alcuni aspiranti genitori intraprendono la strada per avere un figlio attraverso la procreazione assistita: un percorso che richiede tempo, pazienza, denaro, e che non è privo di difficoltà e insidie. Nel contesto italiano la situazione è aggravata dal fatto che non poter avere figli è un tabù di cui non si discute apertamente e coloro che ricorrono alla procreazione assistita spesso lo fanno di nascosto. L’Italia ha, inoltre, una delle leggi più restrittive in materia (la cosiddetta “Legge 40”) e la Chiesa cattolica condanna apertamente questi trattamenti. In un’epoca in cui quasi tutto è considerato possibile, avere figli non è sempre facile, ovvio e “naturale,” come potrebbe sembrare, e la sterilità sta diventando una vera e propria piaga sociale. Tuttavia, è indicativo che nell’editoria e – spesso in forma anonima – su blog e forum, la questione abbia iniziato a essere discussa. Questi sono sintomi di un problema che esiste e sta finalmente cominciando a emergere e a essere affrontato. Nel mio contributo prenderò in considerazione due romanzi contemporanei italiani, pubblicati dopo l’entrata in vigore della “Legge 40” – Confessioni di una aspirante madre di Lisa Corva (2005) e Le difettose di Eleonora Mazzoni (2012) – che raccontano la ricerca, a tratti disperata e ossessiva, della maternità attraverso la procreazione assistita. Le vicende legate al sogno di gravidanza delle protagoniste e le conseguenze derivanti dal fallimento delle tecniche di fecondazione in vitro saranno approfondite con l’ausilio di studi effettuati nell’ambito delle scienze sociali, tra cui quelli di Gayle Letherby, James H. Monach, Karen Throsby e Silvia Vegetti Finzi, nel tentativo di indagare il desiderio di maternità delle protagoniste dei romanzi, il percorso di rinegoziazione della “normalità” e la loro ridefinizione di identità femminile.

This volume of intervalla centres on the themes of choice and conflict, refusal and rejection, and analyses how mothers and non-mothers are perceived in Italian society. The nine essays cover a variety of genres (novel, auto-fiction, theatre) and predominantly address how these perceptions are translated into literary form, ranging from the 1940s to the early twenty-first century. They study topics such as the ambivalent feelings and difficult experiences associated with motherhood (doubt, post-natal depression, infanticide, IVF), the impact of motherhood and non-motherhood on female identity, attitudes towards childless/childfree women, the stereotype of the “good mother,” and the ways in which such stereotypes are rejected, challenged or subverted. Major Italian writers, such as Lalla Romano, Paola Masino, Oriana Fallaci, Laudomia Bonanni and Elena Ferrante, are included in these analyses, alongside contemporary “momoirs” and works by Valeria Parrella, Lisa Corva, Eleonora Mazzoni, Cristina Comencini and Grazia Verasani.

Macroalgae seaweeds such as Ulva lactuca and Gracilaria verrucosa cause problems on the northern coast of the Italian Adriatic Sea because their overabundance hinders the growth of cultivated clams, Rudatapes philippinarum. This study focused on the green synthesis of CuO nanoparticles from U. lactuca and G. verrucosa. The biosynthesized CuO NPs were successfully characterized using FTIR, XRD, HRTEM/EDX, and zeta potential. Nanoparticles from the two different algae species are essentially identical, with the same physical characteristics and almost the same antimicrobial activities. We have not investigated the cause of this identity, but it seems likely to arise from the reaction of Cu with the same algae metabolites in both species. The study demonstrates that it is possible to obtain useful products from these macroalgae through a green synthesis approach and that they should be considered as not just a cause of environmental and economic damage but also as a potential source of income.

InAs quantum wells (QWs) are promising material systems due to their small effective mass, narrow bandgap, strong spin–orbit coupling, large g-factor, and transparent interface to superconductors. Therefore, they are promising candidates for the implementation of topological superconducting states. Despite this potential, the growth of InAs QWs with high crystal quality and well-controlled morphology remains challenging. Adding an overshoot layer at the end of the metamorphic buffer layer, i.e., a layer with a slightly larger lattice constant than the active region of the device, helps to overcome the residual strain and provides optimally relaxed lattice parameters for the QW. In this work, we systematically investigated the influence of overshoot layer thickness on the morphological, structural, strain, and transport properties of undoped InAs QWs on GaAs(100) substrates. Transmission electron microscopy reveals that the metamorphic buffer layer, which includes the overshoot layer, provides a misfit dislocation-free InAs QW active region. Moreover, the residual strain in the active region is compressive in the sample with a 200 nm-thick overshoot layer but tensile in samples with an overshoot layer thicker than 200 nm, and it saturates to a constant value for overshoot layer thicknesses above 350 nm. We found that electron mobility does not depend on the crystallographic directions. A maximum electron mobility of 6.07 × 105 cm2/Vs at 2.6 K with a carrier concentration of 2.31 × 1011 cm−2 in the sample with a 400 nm-thick overshoot layer has been obtained.

Herein, following a circular economy approach, we present the synthesis of luminescent carbon dots via the thermal treatment of chestnut and peanut shells, which are abundant carbon-rich food industry by-products. As-synthesized carbon dots have excellent water dispersibility thanks to their negative surface groups, good luminescence, and photo-stability. The excitation–emission behaviour as well as the surface functionalization of these carbon dots can be tuned by changing the carbon source (chestnuts or peanuts) and the dispersing medium (water or ammonium hydroxide solution). Preliminary in vitro biological data proved that the samples are not cytotoxic to fibroblasts and can act as luminescent probes for cellular imaging. In addition, these carbon dots have a pH-dependent luminescence and may, therefore, serve as cellular pH sensors. This work paves the way towards the development of more sustainable carbon dot production for biomedical applications.

The increase of agri-food wastes by agriculture and industries is one of the main causes of environmental pollution. Here we propose the recycling of Cynara scolymus L. wastes to obtain polymorph II cellulose nanocrystals (CNC). Two different extraction procedures are compared: (i) Soxhlet extraction in an ethanol/toluene mixture, and (ii) water boiling of the agricultural waste. Both procedures were followed by purification of cellulose fibers through bleaching treatments and extraction of cellulose nanocrystals by acid hydrolysis. CNCs have been extensively characterized by FTIR spectroscopy, electrophoretic light scattering measurements, X-ray powder diffraction methods, transmission electron microscopy, and thermogravimetric analyses. Extracted CNC are rod-like-shaped polymorph IIs with a good crystallinity index, and they are characterized by high hydrogen bonding intensity. The ELS measurements on samples from both procedures show good results regarding the stability of the CNC II sol (ζ < −40 ± 5 mV), comparable to that of the CNC polymorph I. Both polymorph II CNCs show better thermal stability, compared to CNC I. The results show that the easy extraction procedure from agricultural Cynara scolymus L. waste can be used to produce high-quality cellulose nanocrystals as a green alternative to the commonly used synthetic route.

Nitroaromatic explosives are the most common explosives, and their detection is important to public security, human health, and environmental protection. In particular, the detection of solid explosives through directly revealing the presence of their vapors in air would be desirable for compact and portable devices. In this study, amino-functionalized carbon nanotubes were used to produce resistive sensors to detect nitroaromatic explosives by interaction with their vapors. Devices formed by carbon nanotube networks working at room temperature revealed trinitrotoluene, one of the most common nitroaromatic explosives, and di-nitrotoluene-saturated vapors, with reaction and recovery times of a few and tens of seconds, respectively. This type of resistive device is particularly simple and may be easily combined with low-power electronics for preparing portable devices.

We report on the self-assembly of core–shell Ge/In–Te nanowires (NWs) on single crystal Si substrates by Metalorganic Chemical Vapour Deposition (MOCVD), coupled to the Vapour–Liquid–Solid (VLS) mechanism, catalysed by Au nanoparticles (NPs). The NWs are formed by a crystalline Ge core and an InTe (II) shell, have diameters down to 15 nm and show oriented growth direction. The role of the MOCVD process parameters and of the NPs size in determining the NWs core–shell microstructure and their alignment was investigated by high-resolution TEM, EDX, XRD and Raman spectroscopy.

The thermodynamic stability of onion-like carbon (OLC) nanostructures with respect to highly oriented pyrolytic graphite (HOPG) was determined in the interval 765-1030 K by the electromotive force (emf) measurements of solid electrolyte galvanic cell: (Low) Pt|Cr3C2,CrF2,OLC|CaF2s.c.|Cr3C2,CrF2,HOPG|Pt (High). The free energy change of transformation HOPG = OLC was found positive below 920.6 K crossing the zero value at this temperature. Its trend with temperature was well described by a 3rd degree polynomial. The unexpected too high values of [Formula: see text] jointly to the HR-TEM, STEM and EELS evidences that showed OLC completely embedded in rigid cages made of a Cr3C2/CrF2 matrix, suggested that carbon in the electrodes experienced different internal pressures. This was confirmed by the evaluation under constant volume of [dP/dT by the α/κ ratio for OLC (0.5 MPa K(-1)) and HOPG (8 Pa K(-1)) where α and κ are the isobaric thermal expansion and isothermal compressibility coefficients, respectively. The temperature dependency of the pressure was derived and utilized to calculate the enthalpy and entropy changes as function of temperature and pressure. The highest value of the internal pressure experienced by OLC was calculated to be about 7 GPa at the highest temperature. At 920.6 K, ΔrH and ΔrS values are 95.8 kJ mol(-1) and 104.1 JK(-1) mol(-1), respectively. The surface contributions to the energetic of the system were evaluated and they were found negligible compared with the bulk terms. As a consequence of the high internal pressure, the values of the enthalpy and entropy changes were mainly attributed to the formation of carbon defects in OLC considered as multishell fullerenes. The change of the carbon defect fraction is reported as a function of temperature.