Non-paraxial design and fabrication of a compact OAM sorter in the telecom infrared

A novel optical device is designed and fabricated in order to overcome the limits of the traditional sorter based on log-pol optical transformation for the demultiplexing of optical beams carrying orbital angular momentum (OAM). The proposed configuration simplifies the alignment procedure and significantly improves the compactness and miniaturization level of the optical architecture. Since the device requires to operate beyond the paraxial approximation, a rigorous formulation of transformation optics in the non-paraxial regime has been developed and applied. The sample has been fabricated as 256-level phase-only diffractive optics with high-resolution electron-beam lithography, and tested for the demultiplexing of OAM beams at the telecom wavelength of 1310 nm. The designed sorter can find promising applications in next-generation optical platforms for mode-division multiplexing based on OAM modes both for free-space and multi-mode fiber transmission.Comment: 12 pages, 8 figure

Behavioral phenotype and autism spectrum disorders in Cornelia de Lange syndrome

Cornelia de Lange syndrome (CdLS) is a congenital disorder characterized by distinctive facial features, growth retardation, limb abnormalities, intellectual disability, and behavioral problems. Cornelia de Lange syndrome is associated with abnormalities on chromosomes 5, 10 and X. Heterozygous point mutations in three genes (NIPBL, SMC3 and SMC1A), are responsible for approximately 50-60% of CdLS cases. CdLS is characterized by autistic features, notably excessive repetitive behaviors and expressive language deficits. The prevalence of autism spectrum disorder (ASD) symptomatology is comparatively high in CdLS. However, the profile and developmental trajectories of these ASD characteristics are potentially different to those observed in individuals with idiopathic ASD. A significantly higher prevalence of self-injury are evident in CdLS. Selfinjury was associated with repetitive and impulsive behavior. This study describes the behavioral phenotype of four children with Cornelia de Lange syndrome and ASDs and rehabilitative intervention that must be implemented

The child with Autism Spectrum Disorders (ASDS): Behavioral and neurobiological aspects

Introduction: The Autism Spectrum Disorders (ASDs) have onset in the first years of life and are characterized clinically by qualitative impairments in social interaction, communication and a restricted repertoire, stereotyped and repetitive interests and activities. Currently there is a medical consensus on the causes of autism: they should not be psychosocial but should be based in biology, especially in the central nervous system abnormalities caused by both inherited and environmental causes. The aim of this study was to study a sample of subjects with Autism Spectrum Disorders (ASDs) with a wide protocol, including neurophysiological and radiological investigations as well as laboratory investigations in order to investigate the neurobiologic basis of the syndrome. Methods: The patients group included 34 subjects diagnosed as having ASDs. All were examined with a protocol of investigations (brain MRI; EEG; VEP, ABR; karyotype; evaluation of brain metabolites; antibodies against neurotrophic agents). In order to evaluate and identify the presence and intensity of autistic symptoms have been used the CARS (Childhood Autism Rating Scale) and ADOS (Autism Diagnostic Observation Schedule) tools. Results and Conclusion. Ninety percent of the subjects had at least one parameter neurobiological disease, the fifty-nine percent have a specific genetic syndrome. This study highlights the different noxae involved in the etiopathogenesis of AD and the percentage that every biological factor has in the development of the autistic phenotype. This study confirms the hypothesis that autism spectrum disorders (ASDs) are a severe neuropsychiatric diseases with strong genetic basis

Autism spectrum disorder in Kabuki syndrome: clinical, diagnostic and rehabilitative aspects assessed through the presentation of three cases

Kabuki syndrome (KS) (Kabuki make-up syndrome, Niikawa-Kuroki syndrome) is a rare genetic disorder first diagnosed in 1981. Kabuki make-up syndrome (KMS) is a multiple malformation/intellectual disability syndrome that was first described in Japan but is now reported in many other ethnic groups. KMS is characterized by multiple congenital abnormalities: craniofacial, skeletal, and dermatoglyphic abnormalities; intellectual disability; and short stature. Other findings may include: congenital heart defects, genitourinary anomalies, cleft lip and/or palate, gastrointestinal anomalies including anal atresia, ptosis and strabismus, and widely spaced teeth and hypodontia. The KS is associated with mutations in the MLL2 gene in some cases were also observed deletions of KDM6A. This study describes three children with autism spectrum disorders (ASDs) and KS and rehabilitative intervention that must be implemented

Pressure stability field of Mg-perovskite under deep mantle conditions: A topological approach based on Bader's analysis coupled with catastrophe theory

The pressure stability field of the Mg-perovskite phase was investigated by characterizing the evolution of the electron arrangement in the crystal. Ab initio calculations of the perovskite structures in the range 0\u2013185 GPa were performed at the HF/DFT (Hartree-Fock/Density Functional Theory) exchange\u2013correlation terms level. The electron densities, calculated throughout the ab-initio wave functions, were analysed by means of the Bader's theory, coupled with Thom's catastrophe theory. To the best of our knowledge the approach is used for the first time. The topological results show the occurrence of two topological anomalies at P~20 GPa and P~110 GPa which delineate the pressure range where Mg-perovskite is stable. The paper accomplishes the twofold objectives of providing a contribution in shading light into the behaviour of the dominant component of the Earth's lower mantle across the D\u2019\u2019 layer and of proposing a novel approach in predicting the stability of a compound at extreme conditions

Test of mode-division multiplexing and demultiplexing in free-space with diffractive transformation optics

In recent years, mode-division multiplexing (MDM) has been proposed as a promising solution in order to increase the information capacity of optical networks both in free-space and in optical fiber transmission. Here we present the design, fabrication and test of diffractive optical elements for mode-division multiplexing based on optical transformations in the visible range. Diffractive optics have been fabricated by means of 3D high-resolution electron beam lithography on polymethylmethacrylate resist layer spun over a glass substrate. The same optical sequence was exploited both for input-mode multiplexing and for mode sorting after free-space propagation. Their high miniaturization level and efficiency make these optical devices ideal for integration into next-generation platforms for mode-division (de)multiplexing in telecom applications.Comment: 4 pages, 1 extended references page, 6 figures. arXiv admin note: substantial text overlap with arXiv:1610.0744

Modified Halloysite Nanotubes: Nanoarchitectures for Enhancing the Capture of Oils from Vapor and Liquid Phases

We prepared hybrid halloysite nanotubes (HNT/sodium alkanoates) in which the inner cavity of the nanoclay was selectively modified. Physicochemical studies evidenced the interactions between HNT and sodium alkanoates, ruled out clay exfoliation, quantified the amount of the loaded substance, and showed an increase of the total net negative charge, allowing us to obtain rather stable aqueous nanoclay dispersions. These dispersions were exploited as inorganic micelles to capture hydrocarbon and aromatic oils in the vapor and liquid states and were revealed to be nonfoaming but very efficient in encapsulating oils. Here, we have fabricated biocompatibile and low-cost inorganic micelles that can be exploited for industrial applications on a large scale

Solving the Frustrated Spherical Model with q-Polynomials

We analyse the Spherical Model with frustration induced by an external gauge field. In infinite dimensions, this has been recently mapped onto a problem of q-deformed oscillators, whose real parameter q measures the frustration. We find the analytic solution of this model by suitably representing the q-oscillator algebra with q-Hermite polynomials. We also present a related Matrix Model which possesses the same diagrammatic expansion in the planar approximation. Its interaction potential is oscillating at infinity with period log(q), and may lead to interesting metastability phenomena beyond the planar approximation. The Spherical Model is similarly q-periodic, but does not exhibit such phenomena: actually its low-temperature phase is not glassy and depends smoothly on q.Comment: Latex, 14 pages, 2 eps figure