Biochemical sites of gene action for melanogenesis in mammals

International audienc

PRADER-WILLI SYNDROME: ORAL FINDINGS

Aim: Prader-Willi syndrome is a rare multisystemic genetic disorder caused by lack of expression of certain paternal genes located on chromosome 15. The syndrome, associated to hypothalamic and pituitary disfunction, is characterized by severe neonatal hypotonia and feeding problems. Neonatal hypotonia is followed, during childhood by hyperphagia and obesity. In addition, hypothalamic alterations can cause intellectual disability, behavioral problems, a high pain threshold, respiratory sleep disorders. The aim of this work is to evaluate the main dental aspects and the therapeutic implications. Methods: an analysis of the literature was performed using databases. Results: common clinical findings: gingivitis and periodontitis, dental and skeletal malocclusions, enamel hypoplasia, tooth wear and dental erosion, bruxism, xerostomia, candidiasis and angular cheilitis, high risk of caries and increased DMFT score.The typical poor oral hygiene in PWS patients is related to qualitative-quantitative changes in saliva and incoordination in tooth brushing. Conclusion: it is necessary to motivate family and patient to maintain oral hygiene. Due to the various systemic and dental problems, a six-monthly follow-up is required since early childhood. Dental treatment purposes require a multidisciplinary approach which includes periodontal and conservative cares. In prosthetics, we suggest the use of removable dentures because of the difficulty in maintaining oral hygiene

A Quantum Yield Map for Synthetic Eumelanin

The quantum yield of synthetic eumelanin is known to be extremely low and it has recently been reported to be dependent on excitation wavelength. In this paper, we present quantum yield as a function of excitation wavelength between 250 and 500 nm, showing it to be a factor of 4 higher at 250 nm than at 500 nm. In addition, we present a definitive map of the steady-state fluorescence as a function of excitation and emission wavelengths, and significantly, a three-dimensional map of the specific quantum yield: the fraction of photons absorbed at each wavelength that are subsequently radiated at each emission wavelength. This map contains clear features, which we attribute to certain structural models, and shows that radiative emission and specific quantum yield are negligible at emission wavelengths outside the range of 585 and 385 nm (2.2 and 3.2 eV), regardless of excitation wavelength. This information is important in the context of understanding melanin biofunctionality, and the quantum molecular biophysics therein.Comment: 10 pages, 6 figure

Behavior of Full-Scale Porous GFRP Barrier under Blast Loads

This research paper is part of the SAS (Security of Airport Structures) Project funded by the European Programme for Critical Infrastructure Protection, whose objective was to develop and deploy a fiber reinforced polymer (FRP) fencing system intended to protect airport infrastructures against terrorist acts. In the paper, the efficacy of the proposed glass FRP discontinuous (porous) barrier under blast loads is presented by showing the results of the blast test campaign conducted on full-size specimens with a focus on the reduction of the blast shock wave induced by the barrier. A simplified model predicting the reduction of the shock wave beyond the barrier is proposed and validated via the experimental data obtained in the project

Earthquake induced floor accelerations on a high-rise building: Scale model tests on a shaking table

The paper discusses results of shaking table tests on an in-scale high-rise building model. The purpose was to calibrate a dynamic numerical model for multi-hazard analyses to investigate the effects of floor acceleration. Accelerations, because of vibration of non-structural elements, affect both the comfort and safety of people. The research investigates the acceleration effects of both seismic and wind forces on an aeroelastic in-scale model of a multi-story building. The paper discusses the first phase of experiments and gives results of floor accelerations induced by several different base seismic impulses. Structural analyses were first performed on the full-scale prototype to take soil-structure interaction into account. Subsequently the scale model was designed through aeroelastic scale laws. Shaking table experiments were then carried out under different base accelerations. The response of the model and, in particular, amplification of effects from base to top are discussed

Shake table tests for the seismic fragility evaluation of hospital rooms

© 2014 John Wiley & Sons, Ltd. Health care facilities may undergo severe and widespread damage that impairs the functionality of the system when it is stricken by an earthquake. Such detrimental response is emphasized either for the hospital buildings designed primarily for gravity loads or without employing base isolation/supplemental damping systems. Moreover, these buildings need to warrant operability especially in the aftermath of moderate-to-severe earthquake ground motions. The provisions implemented in the new seismic codes allow obtaining adequate seismic performance for the hospital structural components; nevertheless, they do not provide definite yet reliable rules to design and protect the building contents. To date, very few experimental tests have been carried out on hospital buildings equipped with nonstructural components as well as building contents. The present paper is aimed at establishing the limit states for a typical health care room and deriving empirical fragility curves by considering a systemic approach. Toward this aim, a full scale three-dimensional model of an examination (out patients consultation) room is constructed and tested dynamically by using the shaking table facility of the University of Naples, Italy. The sample room contains a number of typical medical components, which are either directly connected to the panel boards of the perimeter walls or behave as simple freestanding elements. The outcomes of the comprehensive shaking table tests carried out on the examination room have been utilized to derive fragility curves based on a systemic approach

The BIM-based Integrated Design of the SHiP Project Decay Volume

The Search for Hidden Particles (SHiP) experiment is a new general-purpose fixed target facility proposed at the CERN Super Proton Synchrotron accelerator to search for longlived exotic particles associated with Hidden Sectors and Dark Matter. This paper reports on the BIM integrated design of SHiP’s decay volume, a conical steel vessel under vacuum that should host several large particle physics detector systems. The use of BIM characterized the design of the decay volume, both in the modeling and structural design phase, and in the process definition phase for the realization and implementation in the facility of the device. This procedure helps to minimize the risks of incorrect design and construction of the device during the whole process. With the automation of the virtual model and the use of interoperable software, in addition to speeding up the exchange of information, it is possible also to export the detailed information of the structural design directly to the numerical control machines for the prefabrication of the various steel modules. Then, the BIM approach to support the integrated design of the SHiP project decay volume from the conceptual planning to the construction phase is shown in this work

Pigments mélaniques du pelage de quelques races bovines: le schéma possible de certaines actions géniques

International audienc

Proposal of A Probabilistic Model for Multi-Hazard Risk Assessment of Structures in Seismic Zones Subjected To Blast for the Limit State of Collapse,” Structural Safety

a b s t r a c t It is desirable to verify the structural performance based on a multi-hazard approach, taking into account the critical actions the structure in question could be subjected to during its lifetime. This study presents a proposal for a probabilistic model for multi-hazard risk associated with the limit state of collapse for a reinforced concrete (RC) structure subjected to blast threats in the presence of seismic risk. The annual risk of structural collapse is calculated taking into account both the collapse caused by an earthquake event and the blast-induced progressive collapse. The blast fragility is calculated using a simulation procedure for generating possible blast configurations, and verifying the structural stability under gravity loading of the damaged structure, using a kinematic plastic limit analysis. As a case study, the blast and seismic fragilities of a generic four-storey RC building located in seismic zone are calculated and implemented in the framework of a multi-hazard procedure, leading to the evaluation of the annual risk of collapse