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The epitaxy of silicene-on-Ag(111) renewed considerable interest in silicon (Si) when scaled down to the two-dimensional (2D) limit. This remains one of the most explored growth cases in the emerging 2D material fashion beyond graphene. However, out of a strict silicene framework, other allotropic forms of Si still deserve attention owing to technological purposes. Here, we present 2D Solid Phase Crystallization (SPC) of Si starting from an amorphous-Si on Ag(111) in atomic coverage to gain a crystalline-Si layer by post-growth annealing below 450 °C, namely Complementary Metal Oxide Semiconductor (CMOS) Back-End-of-Line (BEOL) thermal budget limit. Moreover, considering the benefit of the 2D-SPC scheme, we managed to write crystalline-Si pixels on the amorphous-Si matrix. Ourin situandex situanalyses show that an in-plane interface or a lateral heterojunction between amorphous and crystalline-Si is formed. This amorphous-to-crystalline phase transformation suggests that 2D silicon may stem from an epitaxially grown layer and thermal self-organization/assembling.

Epilepsy is a common, often severe, feature of LAMA2-related muscular dystrophy (LAMA2-RD) and could represent its onset and main manifestation, even in the absence of overt muscle involvement. To date, there is no systematic characterization of epilepsy in LAMA2-RD, and its impact on neurodevelopment and on the clinical course remains poorly established. In view of this knowledge gap, we conducted a systematic review of the literature and, as an illustrative example, reported the clinical case of a boy with late-onset LAMA2-related limb-girdle muscular dystrophy presenting with severe epilepsy. Our analyses of the literature data revealed a mean age at first seizure of 8 years, with significant differences between early- versus late-onset disease (5.78 ± 4.11 and 9.00 ± 2.65 years, respectively; p = 0.0007), and complete versus partial merosin deficiency (5.33 ± 3.70 and 10.36 ± 5.49 years, respectively; p = 0.0176). A generalized onset was the most common seizure presentation, regardless of merosin expression levels or the timing of muscular distrophy onset. Cortical malformations were not significantly associated with an earlier epilepsy onset, and were found to be quasi-significantly associated with a greater incidence of focal, or focal and generalized, onset seizures. No clear conclusions could be reached on the electrophysiological and neurodevelopmental features of the disorder, or on the relative efficacy of anti-epileptic treatments; further research on these aspects is needed. This systematic review helps to show that epilepsy in LAMA2-RD may be more than an ancillary manifestation of the disease, but rather one of its core features. A targeted and prompt electroencephalographic and epilepsy assessment, in addition to the specific neuromuscular workup, is therefore mandatory in early clinical management to pursue the best possible outcome for affected children.

Stabilization of silicene and preservation of its structural and electronic properties are essential for its processing and future integration into devices. The stacking of silicene on stanene, creat- ing a Xene-based heterostructure, proves to be a viable new route in this respect. Here we demonstrate the effectiveness of a stanene layer in breaking the strong interaction between silicene and the Ag(111) substrate. The role of stanene as a ‘buffer’ layer is investi- gated by analyzing the optical response of epitaxial silicene through both power-dependent Raman spectroscopy and reflectivity mea- surements in the near infrared (NIR)–ultraviolet (UV) spectral range. Finally, we point out a Xene-induced shift of the silver plasma edge that paves the way for the development of a new approach to engineering the metal plasmonic response.

Background SLC39A8, a gene located on chromosome 4q24, encodes for the manganese (Mn) transporter ZIP8 and its detrimental variants cause a type 2 congenital disorder of glycosylation (CDG). The common SLC39A8 missense variant A391T is associated with increased risk for multiple neurological and systemic disorders and with decreased serum Mn. Patients with SLC39A8-CDG present with different clinical and neuroradiological features linked to variable transferrin glycosylation profile. Galactose and Mn supplementation therapy results in the biochemical and clinical amelioration of treated patients. Results Here, we report clinical manifestations, neuroradiological features and glycophenotypes associated with novel SLC39A8 variants (c.1048G > A; p.Gly350Arg and c.131C > G; p.Ser44Trp) in two siblings of the same Italian family. Furthermore, we describe a third patient with overlapping clinical features harbouring the homozygous missense variant A391T. The clinical phenotype of the three patients was characterized by severe developmental disability, dystonic postural pattern and dyskinesia with a more severe progression of the disease in the two affected siblings. Neuroimaging showed a Leigh syndrome-like pattern involving the basal ganglia, thalami and white matter. In the two siblings, atrophic cerebral and cerebellum changes consistent with SLC39A8-CDG were detected as well. Serum transferrin isoelectric focusing (IEF) yielded variable results with slight increase of trisialotransferrin isoforms or even normal pattern. MALDI-MS showed the presence of hypogalactosylated transferrin N-glycans, spontaneously decreasing during the disease course, only in one affected sibling. Total serum N-glycome depicted a distinct pattern for the three patients, with increased levels of undergalactosylated and undersialylated precursors of fully sialylated biantennary glycans, including the monosialo-monogalacto-biantennary species A2G1S1. Conclusions Clinical, MRI and glycosylation features of patients are consistent with SLC39A8-CDG. We document two novel variants associated with Leigh syndrome-like disease presentation of SLC39A8-CDG. We show, for the first time, a severe neurological phenotype overlapping with that described for SLC39A8-CDG in association with the homozygous A391T missense variant. We observed a spontaneous amelioration of transferrin N-glycome, highlighting the efficacy of MS-based serum glycomics as auxiliary tool for the diagnosis and clinical management of therapy response in patients with SLC39A8-CDG. Further studies are needed to analyse more in depth the influence of SLC39A8 variants, including the common missense variant, on the expression and function of ZIP8 protein, and their impact on clinical, biochemical and neuroradiological features.

Background: Cerebellar hemorrhage (CBH) represents the main form of direct cerebellar injury in preterm infants. Most CBHs occur bilaterally, while isolated unilateral hemorrhages are less frequent and often associated with focal atrophy. Limited and heterogeneous data exist on preterm birth, unilateral CBH and consequent long-term neurodevelopmental and non-motor outcomes. Case report: This is the case of a six-year-old child, born preterm, diagnosed with a complete atrophy of the right cerebellar hemisphere through brain MRI and presenting mild social atypies, visuo-perceptive and pragmatic language impairment, but only minor neurological signs. Discussion: Despite the large extension of the patient's CBH neurological sequelae were mild, likely due to cerebellar plasticity, and only specific deficits in non-motor, behavioral and social skills were shown. Evidence exists on cerebellar contribution to dynamic visual information processing and to perceptual signals detection and prediction, that might explain the presence of non-motor signs.

Stanene is one of the most intriguing two-dimensional (2D) materials because of its nontrivial topological properties. Here, the optical properties from THz to UV of molecular beam deposited tin nanosheets on Al2O3(0001) are reported. The experimental absorption coefficient cannot be described in terms of metallic tin or tin oxides. Nonetheless, a similar optical behavior was predicted by theory for freestanding stanene, thus suggesting the formation of the 2D tin nanosheets with stanene-like properties. These findings show that 2D tin bears appealing optical properties in a broad range of the electromagnetic spectrum, thus paving the way to Xenes-based nanophotonics.

On 11 March 2020, a national lockdown was imposed by the Italian government to contain the spread of COVID19 disease. This is an observational longitudinal study conducted at Fondazione Stella Maris (FSM), Italy to investigate lockdown-related emotional and behavioural changes in paediatric neuropsychiatric population. Families having children (1.5&ndash, 18 years) with neuropsychiatric disorders referred to FSM have been contacted and proposed to fulfil two online questionnaires (General questionnaire and Child Behaviour Check List (CBCL)) to (i) compare (paired two-sample t-tests) the CBCL scores during lockdown with previous ones, and (ii) investigate the influence (multiple linear regression models) of variables such as age, diagnosis grouping (neurological, neurodevelopmental, emotional, and behavioural disorders) and financial hardship. One hundred and forty-one parents fulfilled the questionnaires. Anxiety and somatic problems increased in 1.5&ndash, 5 years subpopulation, while obsessive-compulsive, post-traumatic and thought problems increased in 6&ndash, 18 years subpopulation. In the regression models, younger age in the 1.5&ndash, 5 years subpopulation resulted as &ldquo, protective&rdquo, while financial hardship experienced by families during lockdown was related to psychiatric symptoms increasing in the 6&ndash, 18 years subpopulation. Some considerations, based on first clinical impressions, are provided in text together with comments in relation to previous and emerging literature on the topic.