From Plato's Rational Diameter to Proclus' Elegant Theorem

A novel interpretation of a single sentence in Proclus' Commentary to Plato's "Republic" suggests a virtually algebraic rigorous derivation of an infinite sequence of pairs of side and diameter numbers.Comment: 21 pages, 1 figure -- minor changes added 12/30/202

Complex chromosome rearrangement in a child with microcephaly, dysmorphic facial features and mosaicism for a terminal deletion del(18)(q21.32-qter) investigated by FISH and array-CGH: Case report

We report on a 7 years and 4 months old Greek boy with mild microcephaly and dysmorphic facial features. He was a sociable child with maxillary hypoplasia, epicanthal folds, upslanting palpebral fissures with long eyelashes, and hypertelorism. His ears were prominent and dysmorphic, he had a long philtrum and a high arched palate. His weight was 17 kg (25th percentile) and his height 120 cm (50th percentile). High resolution chromosome analysis identified in 50% of the cells a normal male karyotype, and in 50% of the cells one chromosome 18 showed a terminal deletion from 18q21.32. Molecular cytogenetic investigation confirmed a del(18)(q21.32-qter) in the one chromosome 18, but furthermore revealed the presence of a duplication in q21.2 in the other chromosome 18. The case is discussed concerning comparable previously reported cases and the possible mechanisms of formation

Detailed molecular and clinical investigation of a child with a partial deletion of chromosome 11 (Jacobsen syndrome)

<p>Abstract</p> <p>Background</p> <p>Jacobsen syndrome (JBS) is a rare chromosomal disorder leading to multiple physical and mental impairment. This syndrome is caused by a partial deletion of chromosome 11, especially subband 11q24.1 has been proven to be involved. Clinical cases may easily escape diagnosis, however pancytopenia or thrombocytopenia may be indicative for JBS.</p> <p>Results</p> <p>We report a 7.5 years old boy presenting with speech development delay, hearing impairment and abnormal platelet function. High resolution SNP oligonucleotide microarray analysis revealed a terminal deletion of 11.4 Mb in size, in the area 11q24.1-11qter. This specific deletion encompasses around 170 genes. Other molecular techniques such as fluorescence in situ hybridization and multiplex ligation-dependent probe amplification were used to confirm the array-result.</p> <p>Discussion</p> <p>Our results suggest that the identification and detailed analysis of similar patients with abnormal platelet function and otherwise mild clinical features will contribute to identification of more patients with 11q deletion and JBS.</p

The use of array-CGH in a cohort of Greek children with developmental delay

<p>Abstract</p> <p>Background</p> <p>The genetic diagnosis of mental retardation (MR) is difficult to establish and at present many cases remain undiagnosed and unexplained. Standard karyotyping has been used as one of the routine techniques for the last decades. The implementation of Array Comparative Genomic Hybridization (array-CGH) has enabled the analysis of copy number variants (CNVs) with high resolution. Major cohort studies attribute 11% of patients with unexplained mental retardation to clinically significant CNVs. Here we report the use of array-CGH for the first time in a Greek cohort. A total of 82 children of Greek origin with mean age 4.9 years were analysed in the present study. Patients with visible cytogenetic abnormalities ascertained by standard karyotyping as well as those with subtelomeric abnormalities determined by Multiplex Ligation-dependent Probe Amplification (MLPA) or subtelomeric FISH had been excluded.</p> <p>Results</p> <p>Fourteen CNVs were detected in the studied patients. In nine patients (11%) the chromosomal aberrations were inherited from one of the parents. One patients showed two duplications, a 550 kb duplication in 3p14.1 inherited from the father and a ~1.1 Mb duplication in (22)(q13.1q13.2) inherited from the mother. Although both parents were phenotypically normal, it cannot be excluded that the dual duplication is causative for the patient's clinical profile including dysmorphic features and severe developmental delay. Furthermore, three <it>de novo </it>clinically significant CNVs were detected (3.7%). There was a ~6 Mb triplication of 18q21.1 in a girl 5 years of age with moderate MR and mild dysmorphic features and a ~4.8 Mb duplication at (10)(q11.1q11.21) in a 2 years old boy with severe MR, multiple congenital anomalies, severe central hypotonia, and ataxia. Finally, in a 3 year-old girl with microcephaly and severe hypotonia a deletion in (2)(q31.2q31.3) of about ~3.9 Mb was discovered. All CNVs were confirmed by Fluorescence <it>in situ </it>hybridization (FISH). For the remaining 9 patients the detected CNVs (inherited duplications or deletions of 80 kb to 800 kb in size) were probably not associated with the clinical findings.</p> <p>Conclusions</p> <p>Genomic microarrays have within the recent years proven to be a highly useful tool in the investigation of unexplained MR. The cohorts reported so far agree on an around 11% diagnostic yield of clinically significant CNVs in patients with unexplained MR. Various publicly available databases have been created for the interpretation of identified CNVs and parents are analyzed in case a rare CNV is identified in the child. We have conducted a study of Greek patients with unexplained MR and confirmed the high diagnostic value of the previous studies. It is important that the technique becomes available also in less developed countries when the cost of consumables will be reduced.</p

Towards Highly Automated Driving: Intermediate report on the HAVEit-Joint System

International audienceThis overview article describes the goals, concepts and very preliminary results of the subproject Joint System within the EU-project HAVEit. The goal of HAVEit is to develop and investigate vehicle automation beyond ADAS systems, especially highly automated driving, where the automation is doing a high percentage of the driving, while the driver is still meaningfully involved in the driving task. In HAVEit, an overarching architecture and several prototypes will be built up over time by manufacturers and suppliers. As a trail blazer, a Joint System prototype is under development by an interdisciplinary team of several European research institutes in order to investigate and demonstrate the basic principles of highly automated driving, which will then be gradually applied to vehicles closer to serial production. Starting with sensor data fusion, the Co-System part of the Joint Systems plans manoeuvres and trajectories, which are then used to control active interfaces and, taking into account the results of an online driver assessment, joined with the actions of the driver. While many aspects of this research undertaking are still under investigation, the concept, a first prototype and first results from a simulator evaluation will be sketched

EXPLICIT FINITE DIFFERENCE SCHEMES BASED ON THE MODIFIED METHOD OF CHARACTERISTICS AND THEIR APPLICATION TO THE MISCIBLE DISPLACEMENT PROBLEM

A class of convection-diffusion parabolic boundary value problems is considered in this study. When convection dominates over diffusion, the solutions of such problems exhibit an almost hyperbolic behavior. Initial conditions with steep gradients propagate in space and time in the form of sharp traveling fronts. Efficient algorithms for solving such problems accurately are developed, analyzed and tested. These schemes are based on the modified method of characteristics using finite differences and explicit time integration, and are consequently named Explicit Modified Method of Characteristics or EMMC schemes. For problems in one space dimension, explicit time steps are taken along the characteristics of the hyperbolic part of the differential operator and the spatial grid is simultaneously adapted to track the front. The diffusion term is discretized by finite differences. Error analysis is performed and a mild stability criterion is derived. This criterion is used for automatic adjustment of the time step. For problems in two space dimensions, the explicit time stepping and the grid adaptation take place along directions approximating those of the characteristics. These directions are chosen so that numerical dispersion is minimized and a rectangular spatial grid is retained at all times. The explicit step discretizes part of the convection terms. The remainder and the diffusion terms are discretized by finite differences. Error analysis is again used to derive a stability criterion for automatic step size adjustment. This criterion is qualitatively similar to the Courant-Friedrichs-Lewy one, but substantially milder. The two dimensional EMMC scheme is combined with a Mixed Finite Elements method 4,7 to solve the concentration and pressure equations modeling the Miscible Oil Displacement in a porous medium. The spatial domain used is a "symmetry element" of the repeated five spot pattern. A variety of numerical tests are performed, including cases of adverse mobility ratios and variable reservoir permeability. The computational results show minimal grid orientation effects, reduced artificial dispersion, very low mass balance errors and convergence of the solution with spatial grid refinement. The total absence of any overshoot or undershoot in the computed solutions constitutes an experimental verification of the stability of the method

Unified situation modeling and understanding using hierarchical graphical Model

Situation modeling and understanding is a challenging task due to the scene complexity. In this work we use the extended Joint Directors of Laboratories model for sensor data fusion to solve this challenging task. We propose a non-directed graphical model to represent the global and local contextual dependencies (spatial, temporal, and semantic) between the objects (pedestrians, vehicles, and lanes) and the scene. We develop an inference algorithm to estimate the probability density function at each node of the graph in a bottom up top down approach using non-parametric belief propagation (NBP) scheme. The inferred objects are contextually consistent with respect to others objects and the scene

European Turtle Dove Population Trend in Greece Using Hunting Statistics of the Past 16-Year Period as Indices

The European turtle dove is an important game bird for the hunters in Greece, which is one of a few European countries where its hunting is allowed. The sustainability of the species&rsquo; hunting in Europe is discussed during the last several years due to declines in its population, which forced IUCN to classify it as vulnerable. In Greece, its harvest takes place from 20 August and lasts as long as the presence of the species in the country (mid-October). The ARTEMIS project is a Greek statistical database of hunting characteristics, as revealed by questionnaires distributed to hunters. Statistical indicators such as hunting opportunity and hunting harvest are considered in the literature as reliable to show the population trend of a game species. Therefore, in the present research, hunting statistics are used to determine the population trend of the European turtle dove in Greece. State-space modeling was the main procedure used, a method which allows us to deal with errors that exist from hunting bag data or hunting opportunity data assuming that on average the under and overestimations will be equal. The results of the modeling analysis show a stable trend of the variables used, i.e., hunting opportunity, hunting harvest, and juveniles to adult&rsquo;s ratio. Additionally, the hunting sustainability index showed that the sustainability of the species is improved annually, as a slight positive trend is revealed. This is in favor of the species, if it is considered that the actual percentage of the turtle dove population harvested is lower, since not all doves are encountered by hunters. It is concluded that for the period 2004/05&ndash;2019/20, as indicated by the hunting statistics, the population trend of the European turtle dove in Greece was stable and its harvest sustainable