Advanced materials research for long-haul aircraft turbine engines

The status of research efforts to apply low to intermediate temperature composite materials and advanced high temperature materials to engine components is reviewed. Emerging materials technologies and their potential benefits to aircraft gas turbines were emphasized. The problems were identified, and the general state of the technology for near term use was assessed

ORIGIN OF LIGHT SCATTERING FROM DISORDERED SYSTEMS

Anelastic light scattering is computed numerically for model disordered systems (linear chains and 2-dimensional site and bond percolators), with and without electrical disorder. A detailed analysis of the vibrational modes and of their Raman activity evidences that two extreme mechanisms for scattering may be singled out. One of these resembles scattering from finite size systems, while the other mechanisms originates from spatial fluctuations of the polarizability and is such that modes in even small frequency intervals may have very different Raman activities. As a consequence, the average coupling coefficient $C(\omega)$ is the variance of a zero-average quantity. Our analysis shows that for both linear chains and 2-dimensional percolators the second mechanism dominates over the first, and therefore Raman scattering from disordered systems is essentially due to spatial fluctuations.Comment: 12 pages, Latex, 7 figures available on request

Transcriptional control of the B3GALT5 gene by a retroviral promoter and methylation of distant regulatory elements

We focused on transcription factors and epigenetic marks that regulate the B3GALT5 gene through its retroviral long terminal repeat (LTR) promoter. We compared the expression levels of the B3GALT5 LTR transcript, quantitated by competitive RT-PCR, with those of the candidate transcription factors HNF1\u3b1/\u3b2 and Cdx1/2, determined by Western blot analysis, in colon cancer biopsies, various cell lines, and cell models serving as controls. We found that HNF1\u3b1/\u3b2 were easily detected, irrespective of the amount of LTR transcript expressed by the source, whereas Cdx1/2 were undetectable, and no sample lacking HNF1\u3b1/\u3b2 expressed the LTR transcript. On transfection in proper host cells, both HNF1\u3b1 and HNF1\u3b2 provided detectable LTR transcript, whereas shRNA-mediated silencing of HNF1\u3b2 impaired transcription. Treating cells with 5\u2032-aza-2\u2032-deoxycytidine (5AZA) strongly reduced expression, without affecting HNF1\u3b1/\u3b2, despite the lack of CpG islands in the LTR and proximal sequences. By electrophoresis mobility shift and luciferase reporter assays, the LTR promoter binding and activity did not correlate with the amounts of LTR transcript expressed in the cells and depended on the levels of the transcription factors. We conclude that HNF1\u3b1/\u3b2 are necessary but insufficient to activate and regulate B3GALT5 LTR transcription, which depends on unknown regulatory elements that are active when methylated and located outside of and far from the LTR promoter

Total Hemi-overgrowth in Pigmentary Mosaicism of the (Hypomelanosis of) Ito Type: Eight Case Reports.

Pigmentary mosaicism of the (hypomelanosis of) Ito type is an umbrella term, which includes phenotypes characterized by mosaic hypopigmentation in the form of streaks, whorls, patchy, or more bizarre skin configurations (running along the lines of Blaschko): these cutaneous patterns can manifest as an isolated skin disorder (pigmentary mosaicism of the Ito type) or as a complex malformation syndrome in association with extracutaneous anomalies (most often of the musculoskeletal and/or nervous systems) (hypomelanosis of Ito). Affected individuals are anecdotally reported to have also partial or total body hemi-overgrowth (HOG), which often causes moderate to severe complications.We studied the occurrence and features of HOG in the 114 children and adults with mosaic pigmentary disorders of the Ito type diagnosed and followed up (from 2 to 22 years; average follow-up 16 years) at our Institutions.Eight patients (5 M, 3 F; aged 4 to 25 years; median age 16 years) out of the 114 analyzed (7%) fulfilled the criteria for unilateral HOG, with differences in diameter ranging from 0.4 to 4.0 cm (upper limbs) and 1.0 to 9.0 cm (lower limbs). Moreover, among these 8 patients, 5/8 filled in the 75th to 90th percentile for height; 6/8 had associated kyphoscoliosis; and 5/8 showed cognitive delays. No tumour complications were recorded. Overall, 6/8 HOG patients presented with additional (extracutaneous) syndromic manifestations, apart from the HOG (ie, with a clinical phenotype of hypomelanosis of Ito).The present study, which includes children and adults with the longest follow-up so far recorded, confirms the association between pigmentary mosaicism of the Ito type and HOG lowering previous estimates (7% vs 16%) for HOG in the context of mosaic hypopigmentation. A careful examination, looking at subtle to moderate asymmetries and associated complications within the spectrum of these mosaic pigmentary disorders, is recommended

Pharyngeal airway dimensions: a cephalometric, growth-study-based analysis of physiological variations in children aged 6-17

SummaryOBJECTIVE: The aim was to assess pharyngeal airway dimensions and physiological changes based on lateral cephalometric radiographs from healthy untreated children aged 6-17 years. MATERIALS/METHODS: The sample consisted of 880 lateral cephalograms (412 females and 468 males) of the Zurich Craniofacial Growth Study. Statistical analyses on cephalometric measurements of airway dimensions (distances ‘p': shortest distance between soft palate and posterior pharyngeal wall and ‘t': shortest distance between tongue and posterior pharyngeal wall) and craniofacial parameters were performed. To disclose differences between different age groups, a Kruskal-Wallis test was applied. The influence of gender on ‘p' and ‘t' was analysed by a Mann-Whitney U-test for each age group separately. The Spearman correlation was computed in order to investigate associations between craniofacial parameters. Variables associated with ‘p' and ‘t' were chosen for multiple regression model investigation. RESULTS: The results demonstrated high interindividual variations. A slight influence of age on ‘p' (P = 0.034) could be attested (+1.03mm) but not on ‘t' (P = 0.208). With the exception of the 9-year age group, no significant differences between the genders were found. Correlation analysis revealed several statistically significant correlations between ‘t' or ‘p' and antero-posterior cephalometric variables. All correlation coefficients were, however, very low and the adjusted coefficient of determination also revealed the regression model to be very weak. CONCLUSIONS: The high interindividual variations of ‘p' and ‘t' render the use of reference values problematic. Contrary to other craniofacial structures, neither age-related changes nor sexual dimorphism were found for ‘p' and ‘t'. Any associations to antero-posterior cephalometric characteristics seem lo

Reptilia, Squamata, Tropiduridae, <i>Stenocercus sinesaccus</i> Torres–Carvajal, 2005: Distribution extension

The present study reports the easternmost known record for the tropidurid lizard Stenocercussinesaccus Torres–Carvajal, 2005, at Floresta Nacional de Silvânia, state of Goiás, Brazil, in a transition areabetween cerrado sensu strictu and gallery fores

Acoustic Nature of the Boson Peak in Vitreous Silica

New temperature dependent inelastic x-ray (IXS) and Raman (RS) scattering data are compared to each other and with existing inelastic neutron scattering data in vitreous silica (v-SiO_2), in the 300 - 1775 K region. The IXS data show collective propagating excitations up to Q=3.5 nm^-1. The temperature behaviour of the excitations at Q=1.6 nm^-1 matches that of the boson peak found in INS and RS. This supports the acoustic origin of the excess of vibrational states giving rise to the boson peak in this glass.Comment: 10 pages and 4 figure

Commissioning of the MEG II tracker system

The MEG experiment at the Paul Scherrer Institut (PSI) represents the state of the art in the search for the charged Lepton Flavour Violating (cLFV) $\mu^+ \rightarrow e^+ \gamma$ decay. With the phase 1, MEG set the new world best upper limit on the \mbox{BR}(\mu^+ \rightarrow e^+ \gamma) < 4.2 \times 10^{-13} (90% C.L.). With the phase 2, MEG II, the experiment aims at reaching a sensitivity enhancement of about one order of magnitude compared to the previous MEG result. The new Cylindrical Drift CHamber (CDCH) is a key detector for MEG II. CDCH is a low-mass single volume detector with high granularity: 9 layers of 192 drift cells, few mm wide, defined by $\sim 12000$ wires in a stereo configuration for longitudinal hit localization. The filling gas mixture is Helium:Isobutane (90:10). The total radiation length is $1.5 \times 10^{-3}$ \mbox{X}_0, thus minimizing the Multiple Coulomb Scattering (MCS) contribution and allowing for a single-hit resolution $< 120$ $\mu$m and an angular and momentum resolutions of 6 mrad and 90 keV/c respectively. This article presents the CDCH commissioning activities at PSI after the wiring phase at INFN Lecce and the assembly phase at INFN Pisa. The endcaps preparation, HV tests and conditioning of the chamber are described, aiming at reaching the final stable working point. The integration into the MEG II experimental apparatus is described, in view of the first data taking with cosmic rays and $\mu^+$ beam during the 2018 and 2019 engineering runs. The first gas gain results are also shown. A full engineering run with all the upgraded detectors and the complete DAQ electronics is expected to start in 2020, followed by three years of physics data taking.Comment: 10 pages, 12 figures, 1 table, proceeding at INSTR'20 conference, accepted for publication in JINS

Post-graduate medical education in public health: The case of Italy and a call for action

Public health technical expertise is of crucial importance to inform decision makers\u2019 action in the field of health and its broader determinants. Improving education and training of public health professionals for both practice and research is the starting point to strengthen the role of public health so that current health challenges can be efficiently tackled. At the Association of Schools of Public Health in the European Region (ASPHER) Deans\u2019 & Directors\u2019 2017 Annual Retreat, we presented the structure and management of public health training system in Italy, and we reported recent data on Italian public health specialists\u2019 educational experience, employment opportunities and job satisfaction. Public health training in Italy is implemented in the context of the post-graduate medical education residency programme in Hygiene and Preventive Medicine, delivered by 34 University-based Schools of Public Health. We report relatively high employment rates across the county and wide spectrum of career opportunities for young public health specialists. However, job security is low and training expectations only partially met. We call upon other Schools of Public Health to scale up the survey within the broad ASPHER community in a shared and coordinated action of systematically collecting useful data that can inform the development of public health education and training models, their implementation and fruitful interaction with population health, health systems and services