Mystery(n) Phenotypic Presentation in Europeans: Report of Three Further Novel Missense RNF213 Variants Leading to Severe Syndromic Forms of Moyamoya Angiopathy and Literature Review

Moyamoya angiopathy (MMA) is a rare cerebral vasculopathy in some cases occurring in children. Incidence is higher in East Asia, where the heterozygous p.Arg4810Lys variant in RNF213 (Mysterin) represents the major susceptibility factor. Rare variants in RNF213 have also been found in European MMA patients with incomplete penetrance and are today a recognized susceptibility factor for other cardiovascular disorders, from extracerebral artery stenosis to hypertension. By whole exome sequencing, we identified three rare and previously unreported missense variants of RNF213 in three children with early onset of bilateral MMA, and subsequently extended clinical and radiological investigations to their carrier relatives. Substitutions all involved highly conserved residues clustered in the C-terminal region of RNF213, mainly in the E3 ligase domain. Probands showed a de novo occurring variant, p.Phe4120Leu (family A), a maternally inherited heterozygous variant, p.Ser4118Cys (family B), and a novel heterozygous variant, p.Glu4867Lys, inherited from the mother, in whom it occurred de novo (family C). Patients from families A and C experienced transient hypertransaminasemia and stenosis of extracerebral arteries. Bilateral MMA was present in the proband’s carrier grandfather from family B. The proband from family C and her carrier mother both exhibited annular figurate erythema. Our data confirm that rare heterozygous variants in RNF213 cause MMA in Europeans as well as in East Asian populations, suggesting that substitutions close to positions 4118–4122 and 4867 of RNF213 could lead to a syndromic form of MMA showing elevated aminotransferases and extracerebral vascular involvement, with the possible association of peculiar skin manifestations.     

A correction to the unimodal and bimodal truncated normal distributions for a more accurate representation of extreme and calm wind speeds

The use of wind speed probability density functions is a standard practice to represent different wind regimes. Generally, these regimes are distinguished by the following three characteristics: the shape of the distribution in the central wind speeds, amount of the calm wind speeds (CWS), and extreme wind speeds (EWS). An in‐depth review has highlighted that none of the parametric distributions available is suitable to represent the three main characteristics at the same time. To overcome this gap, the use of the corrected mixture of two truncated normal distributions (CMTTND) and corrected single truncated normal distribution (CTND) are proposed to represent, respectively, bimodal and unimodal wind speed distribution shapes. The CMTTND and CTND are obtained by introducing a correction, respectively, to the mixture of two truncated normal distributions (MTTND) and to the single truncated normal distribution (TND). The MTTND and TND permit an accurate representation of distributions with high levels of CWS. The CMTTND and CTND employ a new parameter, to accurately quantifying also the relative frequencies associated with EWS. The performance of the CMTTND and CTND was assessed using a goodness‐of‐fit (GOF) test and statistical measures of error in the evaluation of the characteristic mean wind speeds. The analytical expressions of these mean wind speeds are obtained and validated by a numerical integration method for the first time in this work. The accuracy of these distributions is compared with that of other conventional probability distribution models, of which three are unimodal and six bimodal, in four Italian locations and three American locations. The analysis of the results showed that the CTND and CMTTND allow obtaining high GOF of the experimental distributions with R² and RMSE higher and lower than, respectively, 0.977 and 0.054. Moreover, the CTND results in the most accurate distribution in the estimation of the characteristic mean wind speeds in the case of localities with unimodal experimental distributions and the CMTTND in the case of localities with bimodal experimental distributions. Contrary to other distribution, CTND and CMTTND accuracies grow by increasing the grade of the characteristic mean wind speed by reaching also estimation values lower than 2% of the real ones. This is a great advantage in the wind energy source determination in a location since the available energy depends on the mean cubic wind speed.     

Effect of anionic substitution on the high temperature stability of polymer-derived SiOC glasses

In this study the high temperature stability (crystallization and decomposition) of two silicon oxycarbide glasses with a similar amount of free carbon (8.3 vs 9.6 wt%) but different content of Si-C bonds (SiC_0.22O_1.57 vs SiC_0.07O_1.86) is presented. The two SiOC glasses are obtained from the same precursor (2 µm methyl-silsesquioxane spheres) via pyrolysis at 1100°C in inert (Ar) or reactive (CO₂) atmospheres. Further annealing in Ar flow at temperatures above 1100°C and up to 1500°C is performed and the samples are characterized by Fourier Transformed Infrared Spectroscopy (FT-IR) and X-ray diffraction (XRD). For comparison purposes the same precursor was annealed in air flow to obtain SiO₂ and its high temperature evolution is also studied. Results suggest that the onset for the carbothermal reduction is not dependent on the amount of Si-C bonds. Moreover, contrary to what is usually reported in the scientific literature, silica phase present in the SiOC glasses does not show, in the same experimental conditions, superior crystallization resistance compared to pure silica glass.     

A non-linear dynamic modelling approach for the characterization and error compensation in sampling oscilloscopes

A mathematical modelling approach is proposed for measurement-based characterization of non-linear dynamic sources of error in the vertical channel of a sampling oscilloscope. The proposed approach has been derived from a recently proposed modified Volterra series expansion which, under particular conditions, provides fast convergence and can be truncated to the first integral term. A possible characterization procedure, based on instrument testing under sinusoidal AC input signals with different frequencies and variable DC bias components, is described and used to evaluate the performances of a commercial oscilloscope. The waveforms obtained by using the identified model are compared with the experimental ones for model validation; successively the model is used for the error compensation of the memory effects.     

Synthesis and characterisation of a nematic homo-polyurethane

The presence of hydrogen bonds in the chemical structure of polymers promotes and stabilises the crystalline phase. For liquid crystalline (LC) polymers, the side insertion of aliphatic units to the mesogenic unit is a suitable artifice to decrease the crystalline stability, without significantly affecting the stability of the LC phases. Here, we report on the synthesis of a LC homo-polyurethane with high hydrogen bond concentration along the chain and bearing an n-pentyl side-chain. Rheological behaviour, thermal analysis, and X-ray diffraction show that the stable LC phase is the nematic.     

ANN based demodulator for UMTS signal measurements

The paper proposes the use of the Artificial Neural Network (ANN) to design a new demodulator architecture of the telecommunication signals. This demodulator is designed to operate into the measurement instruments of modulated signals according to the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access, that is the third generation mobile telephone standard. It is developed on the basis of the Multi-Layer Perceptron ANN and it permits to perform in one shot both the descrambling and the despreading operations. Numerical tests performed by using signals according to the UMTS standard show that the ANN demodulator can guaranty greater accuracy than the traditional one in the case the modulated signal is affected by high level of both noise and distortion.     

Distributed advance reservation of real-time connections

The ability to reserve real-time connections in advance is essential in all distributed multiparty applications (i.e., applications involving multiple human beings) using a network that controls admissions to provide good quality of service. This paper discusses the requirements of the clients of an advance reservation service, and a distributed design for such a service. The design is described within the context of the Tenet Real-Time Protocol Suite 2, a suite being developed for multiparty communication, which will offer advance reservation capabilities to its clients, based on the principles and the mechanisms proposed in the paper. Simulation results providing useful data about the performance and some of the properties of these mechanisms are also presented. We conclude that the one described here is a viable approach to constructing an advance reservation service within the context of the Tenet Suites as well as that of other solutions to the multiparty real-time communication problem.     

``Possible is certain' is desirable and can be expressive

The partial stable models of a logic program form a class of models that include the (unique) well-founded model, total stable models and other two interesting subclasses: maximal stable models and least undefined stable models. As stable models different from the well-founded are not unique, DATALOG queries do not in general correspond to functions. The question is: what are the expressive powers of the various types of stable models when they are restricted to the class of all functional queries? The paper shows that this power does not go in practice beyond the one of stratified queries, except for least undefined stable models which, instead, capture the whole Boolean hierarchy BH. Finally, it is illustrated how the latter result can be used to design a ``functional'' language which, by means of a disciplined usage of negation, allows to achieve the desired level of expressiveness up to BH so that exponential time resolution is eventually enabled only for hard problems.