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Functional connectivity (FC) can be represented as a network, and is frequently used to better understand the neural underpinnings of complex tasks such as motor imagery (MI) detection in brain-computer interfaces (BCIs). However, errors in the estimation of connectivity can affect the detection performances. In this work, we address the problem of denoising common connectivity estimates to improve the detectability of different connectivity states. Specifically, we propose a denoising algorithm that acts on the network graph Laplacian, which leverages recent graph signal processing results. Further, we derive a novel formulation of the Jensen divergence for the denoised Laplacian under different states. Numerical simulations on synthetic data show that the denoising method improves the Jensen divergence of connectivity patterns corresponding to different task conditions. Furthermore, we apply the Laplacian denoising technique to brain networks estimated from real EEG data recorded during MI-BCI experiments. Using our novel formulation of the J-divergence, we are able to quantify the distance between the FC networks in the motor imagery and resting states, as well as to understand the contribution of each Laplacian variable to the total J-divergence between two states. Experimental results on real MI-BCI EEG data demonstrate that the Laplacian denoising improves the separation of motor imagery and resting mental states, and shortens the time interval required for connectivity estimation. We conclude that the approach shows promise for the robust detection of connectivity states while being appealing for implementation in real-time BCI applications., Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible

The Say-Barber-Biesecker-Young-Simpson variant of Ohdo syndrome (SBBYSS) and Genitopatellar syndrome (GTPTS) are 2 rare but clinically well-described diseases caused by de novo heterozygous sequence variants in the KAT6B gene. Both phenotypes are characterized by significant global developmental delay/intellectual disability, hypotonia, genital abnormalities, and patellar hypoplasia/agenesis. In addition, congenital heart defects, dental abnormalities, hearing loss, and thyroid anomalies are common to both phenotypes. This broad clinical overlap led some authors to propose the concept of KAT6B spectrum disorders. On the other hand, some clinical features could help to differentiate the 2 disorders. Furthermore, it is possible to establish a genotype-phenotype correlation when considering the position of the sequence variant along the gene, supporting the notion of the 2 disorders as really distinct entities.

This paper presents a novel space-time recursive least-squares adaptive algorithm, which performs filter coefficients updates in space and postponed filtering in time. The algorithm is used for intersymbol interference suppression in optical camera communications, which is a subgroup of visible light communication systems. Optical camera communications uses image sensor receivers, as those available in smartphones, tablets, and laptops, to detect changes in light intensity in order to allow data transmission. The achievable data transmission rate of optical camera communication systems is nowadays constrained by the frame-per-second rate achieved by those devices, so that the spatial dimension, e.g., multiple-input multiple-output techniques, are typically exploited. Spatial intersymbol interference could arise and image blurring can be an issue especially when the link distance grows and/or when the receiver is in mobility. We present here a semiblind spatial fractionally spaced equalizer that uses a novel space-time recursive least-square adaptive algorithm to counteracts the blur introduced by the optical channel. Numerical results show how the bit error rate can be drastically reduced in both motion and out-of-focus blur scenarios.

Indoor access to the Internet via visible light communication (VLC) technology is becoming an issue and in this sense system planning requires to look at the number of light-emitting diodes (LEDs) to be used. This task can be accomplished by looking at different performance metrics. We consider the problem of optimal footprint mapping by taking into account the achievable user rate when handover procedures take place due to user mobility. This problem is equivalent to the optimal LEDs placement. In this regard, it is shown that several parameters influence system performance starting from the data rate of download, the speed of the user in the room as well the handover time. In this context, we derive a mathematical tool for VLC network planning and show the performance that can be achieved as a function of different parameters.

In this paper, an unsupervised model-based texture reproduction technique is described. In accordance with the Julesz's (1962) conjecture, the statistical properties of the prototype up to the second order are copied in order to generate a synthetic texture perceptually indistinguishable from the given sample. However, this task is accomplished using a hybrid approach which operates partially in the spatial domain and partially in a multiresolution domain. The latter employed is the circular harmonic function (CHF) domain since it has been proven to be well suited for mimicking the behavior of the human visual system (HVS). This approach allows, for a wide range of textures typologies, obtaining synthetic textures that better match the prototype with respect to the ones obtained using techniques based on the Julesz's conjecture operating only in the spatial domain, and to dramatically reduce the computational complexity of similar methods operating only in the multiresolution domain.

Primary pachydermoperiostosis (PDP) is a rare syndrome, characterized by digital clubbing, periostosis, and pachydermia. We have evaluated biochemical bone turnover markers, including components of interleukin-6 (IL-6) and osteoprotegerin/receptor activator of nuclear factor (NF)-?B ligand (OPG/RANKL) systems, in an 18-year-old man affected by primary PDP. The acute phase of the disease was characterized in our patient by high serum levels of IL-6 and RANKL. The observed high serum levels of these parameters are associated with increased values in markers of bone resorption (degradation products of C-terminal telopeptides of type-I collagen and urinary hydroxyproline/creatinine ratio) and reduced serum levels of bone alkaline phosphatase, a marker of bone formation. Serum levels of osteotrophic hormones were in the normal range. Our data suggest that, despite the radiographic findings, the acute phase of primary PDP is characterized by increased bone resorption, probably mediated by IL-6 and RANKL. Read More: http://informahealthcare.com/doi/abs/10.1080/03009740701772457

The ever increasing need to be able to take advantage of broadband services without the need to increase the electromagnetic pollution, has led the scientific community, in recent years, to look for alternatives to the use of a radio frequency communication. From this, it stems the need of budding paradigm of visible light communications. In the context of the activities of the IEEE 802.15.7 Task Group, a new modulation format named Color Shift Keying (CSK), based on sending signals spaced in the domain of the wavelength able to both support the communication and the illumination of indoor environments has been tackled. In this paper, a transmission scheme based on the use of the CSK modulation which also makes use of a modulation format that descends from the Pulse Position Modulation (PPM) has been proposed. The aim of this contribution is also proposing the receiver architecture for that kind of transmission and then evaluate its performance in terms of Bit Error Rate (BER) of Transmission Rate by performing also comparisons with the literature. The proposed scheme is robust with respect to optical interference and presents high rate and low BER at the cost of a bit complexity increasing with respect to other approaches.

The urinary benzene metabolite trans,trans-muconic acid (MA) was determined in 144 children living in Campania (Italy): 92 from Naples (1,300,000 inhabitants), designated as an urban source, and compared to 52 from Pollica (300 inhabitants), considered a rural, background exposure for benzene. The children participating in the study were tested by an anonymous questionnaire about the possible sources of exposure to benzene. Quantifiable levels of MA were found in 63% of the urine samples analyzed. Setting the value of nondetectable urinary samples at 7 microg/L MA, a value that is one-half of the instrument detection limit of 14 microg/L, the mean urinary concentration levels were 98.7+/-81.0 microg/L and 48.4+/-71.7 microg/L in Naples and Pollica, respectively; adjustment of these values to creatinine clearance resulted in MA levels of 141.2+/-145.4 microg/L in Naples and 109.8+/-133.2 microg/L in Pollica. Passive smoke exposure did not significantly affect urinary MA levels, but proximity of the home to traffic increased urine MA content. Data show that MA can be utilized as a biomarker for exposure; however, a clear-cut association to benzene requires personal monitoring and control of dietary sorbic acid.

This work extends the Bussgang blind equalization algorithm to the multichannel case with application to image deconvolution problems. We address the restoration of images with poor spatial correlation as well as strongly correlated (natural) images. The spatial nonlinearity employed in the final estimation step of the Bussgang algorithm is developed according to the minimum mean square error criterion in the case of spatially uncorrelated images. For spatially correlated images, the nonlinearity design is rather conducted using a particular wavelet decomposition that, detecting lines, edges, and higher order structures, carries out a task analogous to those of the (preattentive) stage of the human visual system. Experimental results pertaining to restoration of motion blurred text images, out-of-focus spiky images, and blurred natural images are reported.

In this paper, a model based texture classification procedure is presented. The texture is modeled as the output of a linear system driven by a binary image. This latter retains the morphological characteristics of the texture and it is specified by its spatial autocorrelation function (ACF). We show that features extracted from the ACF of the binary excitation suffice to represent the texture for classification purposes. Specifically, we employ a moment invariants based technique to classify the ACF. The resulting proposed classification procedure is thus inherently rotation invariant. Moreover, it is robust with respect to additive noise. Experimental results show that this approach allows obtaining high correct rotation-invariant classification rates while containing the size of the feature space.

Wireless sensor networks (WSN), i.e. networks of autonomous, wireless sensing nodes spatially deployed over a geographical area, are often faced with acquisition of spatially sparse fields. In this paper, we present a novel bandwidth/energy efficient CS scheme for acquisition of spatially sparse fields in a WSN. The paper contribution is twofold. Firstly, we introduce a sparse, structured CS matrix and we analytically show that it allows accurate reconstruction of bidimensional spatially sparse signals, such as those occurring in several surveillance application. Secondly, we analytically evaluate the energy and bandwidth consumption of our CS scheme when it is applied to data acquisition in a WSN. Numerical results demonstrate that our CS scheme achieves significant energy and bandwidth savings wrt state-of-the-art approaches when employed for sensing a spatially sparse field by means of a WSN., Comment: Submitted to EURASIP Journal on Advances in Signal Processing

We present a case of ultrasonographic prenatal diagnosis at 24 weeks of femur-fibula-ulna (FFU) complex. To our knowledge, this is the first report of an early prenatal diagnosis of FFU.

In this paper the use of brain waves as a biometric identifier is investigated. Among the very different protocols that can be used to acquire the electroencephalogram signal (EEG) of an individual we rely on a very simple one: closed eyes in resting conditions. A database of 48 healthy subjects, collected by the authors at the neurophysiology laboratory of the IRCCS Fondazione Santa Lucia, Roma, Italy, has been used for the experiments. Signals acquired from triplets of electrodes have been employed in the experimentations. In more detail, ten different triplets have been used separately in the experiments in order to speculate about the most suitable triplet to capture the occurring phenomena. Feature vectors constituted by the reflection coefficients of a six order AR model have been extracted for each used channel thus giving rise to a feature vector of length eighteen. A polynomial regression based classification is then employed. This analysis has been performed for three different frequency bands for each of the ten different triplet under analysis. The obtained genuine acceptance rate is of 96.08%.

The aim of this study was to elucidate if the TV commercials that were remembered by the subjects after their observation within a documentary elicited particular brain activity when compared to the activity generated during the observation of TV commercials that were forgotten. High resolution EEG recordings were performed in a group of 10 healthy subjects with the steady state somatosensory evoked potentials (SSSEPs) technique, in which a series of light electrical stimulation at the left wrist were delivered at the frequency of 20 Hz. The brain activity was indexed by the phase delay of the EEG spectral responses at 20 Hz with respect to the stimulus delivering and evaluated at the scalp level as well as at the cortical surface using several regions of interest coincident with the Brodmann areas (BAs). Results suggest that the cerebral processes involved during the observation of TV commercials that were remembered by the population examined (RMB dataset) are generated by the posterior parietal cortices and the prefrontal areas, rather bilaterally. These results are compatible with previously results obtained in literature by using MEG and fMRI devices during similar experimental tasks. High resolution EEG is able to summarize, with the use of SSSEPs methodologies, the behavior of the estimated cortical networks subserving the proposed memory tasks. It is likely that such tool could play a role in the next future for the investigation of the neural substrates of the human behavior in decision-making and recognition tasks.

A twin stage texture synthesis-by-analysis method is presented. It aims to approximate first- and second-order distributions of the texture, accordingly to the Julesz conjecture. In the first stage, the binary textural behavior of a given prototype is represented by means of a hard-limited Gaussian process. In the second stage, the texture is synthesized by passing the binary hard-limited Gaussian process through a linear filter followed by a zero memory histogram equalizer.

An unsupervised color texture synthesis-by analysis method is described. The texture is reproduced to appear perceptually similar to a given prototype by copying its statistical properties up to the second order. The synthesized texture is obtained at the output of a single-input three-output nonlinear system driven by a realization of a white Gaussian random field. Significant complexity reduction is gained by exploiting the rank deficiency of the cross power spectral density matrix of the color texture samples.

Overgrowth Syndromes (OS) – Beckwith-Wiedeman (BW), Simpson-Golabi-Behmel, Perlman, Sotos, Weaver (WS), Proteus, KlippelTrenaunay and some other heterogeneous conditions – are characterized by an excessive prenatal and postnatal growth. As some of them have a poor prognosis, a correct prenatal diagnosis is essential. So far, just a few of prenatal diagnosis of OS have been reported, mostly regarding the BW one. We report the first prenatal diagnosis of Weaver syndrome, in a low risk pregnancy, detected as early as the 22 weeks’ gestation, in a G2 P1 28-year-old Caucasian woman. Parents were non related. The patient was referred to our tertiary centre because of a presumptive diagnosis of BW syndrome, that was excluded because there was neither omphalocele nor macroglossia. 2D US scan was performed with an Hitachi Logos machine (Esaote), and the images were further elaborated in a 3D freehand mode. The 2D scan showed a single living fetus with all the biometric parameters above the 99◦ centile for gestational age. The fetus showed as well: broadening of long bones epiphyses; external male genitalia with micropenis; enlarged hyperechogenic kidneys with severe hydronephrosis; camptodactyly with clinodactyly of fifth digits; enlarged liver; long, everted and broad upper lip.; large ears; enlarged plica nucalis > 9 mm; polyhydramnios. Amniocentesis showed a normal male, 46XY, karyotype. 3D surface rendering images better defined the 2D findings, especially as for the fetal profile, hands and kidneys was concerning, allowing us to postulate a prenatal diagnosis of Weaver syndrome. After extensive genetic counselling, parents opted for pregnancy termination, and a stillborn fetus weighing 788 g was delivered. Dismorphological, X-Ray and necroscopic examination confirmed the prenatal diagnosis of WS. We believe that 3D scan is helpful in making an accurate prenatal diagnosis in case of OS, permitting parents to decide in order to pregnancy termination.

VATER association is an acronym for vertebral defects, anal atresia, tracheoesophageal fistula with esophageal atresia, and renal anomalies. It is rare and sporadic and with no recognized teratogen or chromosomal abnormality. A mitochondrial DNA disorder has been suggested. To date a few of prenatal diagnosis of VATER association have been reported in literature. We report a case of VATER association diagnosed as earlier as the 20th week of gestation associated with a number of fetal anomalies. The consultant, a 33-year old Caucasian woman, gravida3, para1, was referred to our prenatal diagnosis unit because of a previous US scan showing a single vessel umbilical cord, an omphalomesenteric cyst, hypoplasia of left cerebellar hemisphere, ectasia of the aortic arch, a suspicious of anal atresia, sacral anomalies. Normal female foetal karyotype, 46 XX, obtained by amniocentesis, was found. The 20th-week scan confirmed the previous diagnosis but the cerebellar hypoplasia showing as well a coarctation of the descending aorta, a mild bilateral renal pyelectasis with a dysplastic appearance, a diagnosis of sacral agenesia was made. Genitalia was definitively ambiguous with an hypertrophic tuberculum ending with an anechoic cyst showing gross variation during the scan as for the urethrocele. Stomach was not detected during the all US examination. Even tough, due to the earlier of the gestational week, there were no signs of tracheoesophageal fistula, on the basis of the US scan a diagnosis of VATER syndrome associated with ambiguous genitalia was made. After prenatal and genetic counselling parents decided for pregnancy termination at 20 weeks of gestation. Dismorphological and X-ray examination confirmed the US diagnosis and necroscopy further detected an esophageal atresia. This case confirm that the VATER association can be readily diagnosed in utero, and that prenatal diagnosis can contribute to clinical decisions regarding pregnancy.

Chondrodysplasia with snail-like pelvis (Schnechenbecken dysplasia) is a rare distinct, lethal, short-limbed dwarfism. We describe the clinical and radiological features of a new case in an Italian family.

We describe a case of semi-lethal chondrodysplasia with skeletal manifestations, detectable at birth, typical of the round femoral inferior epiphysis dysplasia (RFIED) or 'Glasgow' variant. Immunological abnormalities and Hirschsprung disease, so far described only in cartilage hair hypoplasia (CHH), were documented during the first months of life in our patient. These findings confirm the hypothesis that RFIED is a form of CHH with early infantile onset.

The tolerance of post-larval and fingerling sea bass, Dicentrarchus labrax and striped mullet, Mugil cephalus , to gas supersaturated seawater was evaluated, along with the influence of seawater temperature on the tolerance of post-larval sea bass to gas super-saturation. The 96 h LC 50 values for post-larvae of the two species tested at 20°C were similar: 127.2% TGP (125.2–129.4% TGP) for sea bass and 129.4% TGP (124.7–135.0% TGP) for striped mullet. The 96 h LC 50 values for fingerlings tested at 20°C were 116.0% TGP (112.0–124.2% TGP) for sea bass and 124.8% TGP (121.4–127.2% TGP) for striped mullet. For both species, fingerlings were less tolerant of supersaturated seawater than were post-larvae. Post-larval sea bass were less tolerant of gas supersaturated water at 26°C than at 20°C.

The generation of down-converted frequency waves in the nonlinear propagation of acoustic waves is examined, in order to investigate the effects produced by the finiteness of the medium or of the media of interaction. Oscillations of the directivity patternsvs. the width of the media of interaction are set in evidence and related to resonance conditions of the medium cavity.

The most successful technique used to investigate the properties of the matter by means of elastic wave interaction is the well known pulsed echo system.The fundamental reason is that this method has the best intrinsic axial resolution as compared to the quasi-optical, holographic and tomographic techniques. As far as ultrasound medical diagnostic is concerned, in recent years the transducer design and technology have made considerable progress and presently single or array transducers with very large bandwidths are available and employed in sophisticated imaging systems.

We describe three patients, originating from three different Italian localities, affected by the cardio-facio-cutaneous (CFC) syndrome. In addition to a varying degree of mental retardation, these patients present characteristics consisting of a peculiar face with bitemporal frontal constriction and other anomalies involving the eyes, nose, ears, hair, skin, and heart that are consistent with this diagnosis.

En partant du cas isotrope, on montre que la pression mode de vibration de l'element de ceramique piezoelectrique des reseaux de transducteurs peut etre etudie en etablissant les ondes de Lamb d'ordre nul symetriques stationnaires

This retrospective cohort study was planned to determine whether recommendations to take folic acid have in fact lessened the risk of neural tube defects. Recommendations typically include eating a healthy diet and takingfolic acid supplements when planning pregnancy or throughout the childbearing years. In a few countries, including the United States, flour is fortified so that much of the population will receive at least a small supplemental amount of folic acid. Many governments promote the use of supplements because folic acid is inexpensive, safe, and easy to use. The authors acquired information on more than 13 million births from 13 birth defects registries in Norway that monitored rates of neural tube defects from 1988 to 1998. Cases of anencephaly and spina bifida totaled 8636. Rates of defects were stable during the 10-year monitoring interval in most areas. There were no evident changes in rates of defects after local recommendations were issued. Comparable findings were obtained when analyzing anencephaly and spina bifida separately and combined. Folic acid use in Europe is, in general, low; in Norway, it is approximately 10%. In China, intensive educational efforts and a high rate of planned pregnancies probably are responsible for the effectiveness of a public health campaign to promote the use of folic acid supplements. Rates of folic acid use generally follow economic and educational trends. Fortifying flour with folic acid holds promise for delivering some folic acid to a large part of the population, crossing social and economic barriers. Blood folate levels have increased rapidly where this practice is followed. It is estimated that thousands of neural tube defects occurring since 1992 could have been prevented.

The analysis of 236 Italian patients with Paget's bone disease showed higher clinical severity and greater frequency of neoplastic degeneration among patients who live or descend from individuals living in the Campania region (southern Italy). A prevalent involvement of the spine and the skull, the sites preferentially involved in giant cell tumors complicating Paget's disease, was also shown in familial cases from this geographical region. Introduction: The Campania region in southern Italy has been recently indicated as a high prevalence area for Paget's disease of bone (PDB), and most pagetic families with multiple occurrence of neoplasms in affected members were from this geographical region. Materials and Methods: We evaluated the PDB epidemiological characteristics in 125 patients from Campania in comparison with 111 patients from other Italian regions. Twenty-three patients from Campania and 26 patients from other Italian areas had at least one first-degree relative affected by PDB (familial cases). The remaining patients made up the sporadic cases. Results: Among subjects from Campania, the patients in the familial group tended to come from larger families and showed at diagnosis higher serum total alkaline phosphatase, larger extension of disease, and earlier mean age with respect to patients with PDB of the sporadic group. The skull, spine, and humerus were the sites preferentially involved in the familial cases. In contrast, no such differences were observed between familial and sporadic PDB cases among patients from the other geographical areas, except for a lower age at diagnosis. An increased PDB clinical severity was finally observed in the PDB cohort from Campania in comparison with patients from other Italian regions. Neoplastic degeneration of pagetic bones (osteosarcoma and giant cell tumor) was exclusively observed in patients with polyostotic PDB from Campania. Conclusions: We showed a higher clinical severity of PDB with occurrence of neoplastic degeneration in the high prevalence area of Campania, with its maximum expression in cases with familial disease. This peculiar pattern might be traced to genetic predisposition and/or to the abnormal impact of a still undefined environmental trigger.

In this paper, we present a texture classification procedure that makes use of a blind deconvolution approach. Specifically, the texture is modeled as the output of a linear system driven by a binary excitation. We show that features computed from one-dimensional slices extracted from the two-dimensional autocorrelation function (ACF) of the binary excitation allows representing the texture for rotation-invariant classification purposes. The two-dimensional classification problem is thus reconduced to a more simple one-dimensional one, which leads to a significant reduction of the classification procedure computational complexity.

This work addresses the problem of blind image deblurring, that is, of recovering an original image observed through one or more unknown linear channels and corrupted by additive noise. We resort to an iterative algorithm, belonging to the class of Bussgang algorithms, based on alternating a linear and a nonlinear image estimation stage. In detail, we investigate the design of a novel nonlinear processing acting on the Radon transform of the image edges. This choice is motivated by the fact that the Radon transform of the image edges well describes the structural image features and the effect of blur, thus simplifying the nonlinearity design. The effect of the nonlinear processing is to thin the blurred image edges and to drive the overall blind restoration algorithm to a sharp, focused image. The performance of the algorithm is assessed by experimental results pertaining to restoration of blurred natural images.

The problem of image texture stochastic modeling by means of the 2D Wold decomposition is addressed. Specifically, the 2D Wold decomposition additively separates a texture into a deterministic and an indeterministic component. Since these components are shown to be statistically orthogonal, for textures having a distribution that significantly deviates from Gaussianity, it is possible, in principle, to establish some link between the two components. The aim of this contribution is to show how the indeterministic component can be predicted from the deterministic one by means of suitable nonlinear schemes. The hierarchical structure of the 2D Wold decomposition is thus generalized to deal with the non-Gaussian behavior of most of the natural textures of interest.

The authors propose a new approach for the synthesis of natural video textures using a fractal- based approach. Specifically, a video texture is modelled according to the three-dimensional (3D) extended self-similar (ESS) model introduced, which generalises the fractional Brownian motion process. The analysis of original video textures is based on the estimation of the autocorrelation functions (ACFs) of the textures' increments. The 3D-ESS model is then used to synthesise a process whose increments have the same ACFs of the given prototype. The synthesis is accomplished by generalising to the 3D case the incremental Fourier synthesis algorithm. Experimental results for the analysis and synthesis of natural video textures are eventually provided.

The authors describe a new sign by postmortem autopsy of thesubtype 2 of Pfeiffer s and the possibility of prenatal diagnosis