635 research outputs found
Impaired glucose metabolism in subjects with the Williams-Beuren syndrome. A five-year follow-up cohort study
Objective. The Williams-Beuren syndrome (WS) is associated with impaired glucose metabolism (IGM) early in adulthood. However, the pathophysiology of IGM remains poorly defined, due to the lack longitudinal studies investigating the contribution of β-cell dysfunction and impaired insulin sensitivity. This study aimed at assessing incidence of IGM and the underlying mechanisms in WS adults.
Methods. This observational, longitudinal (5-year), cohort study enrolled thirty-one consecutive WS subjects attending a tertiary referral center. An oral glucose tolerance test (OGTT) was performed yearly and used to classify patients as normal or IGM, including impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) and diabetes mellitus (DM), and to calculate surrogate measures of insulin secretion and/or sensitivity.
Results. IGM patients were 18 (58.1%, three DM) at baseline and 19 (61.3%, five DM) at end-of-follow-up. However, 13 individuals changed category of glucose homeostasis in both directions during follow-up (8 progressors, 5 regressors) and 18 did not (8 non-progressors, 10 non-regressors). New cases of IGM and DM were 11.1 and 2.53 per 100 persons-year, respectively, and were treated non-pharmacologically. In the whole cohort and, to a higher extent, in progressors, indices of early-phase insulin secretion and insulin sensitivity decreased significantly from baseline to end-of-follow-up, with concurrent reduction of the oral disposition index and insulin secretion-sensitivity index-2 (ISSI-2), compensating insulin secretion for the level of insulin resistance. No baseline measure independently predicted progression, which correlated with change from baseline in ISSI-2. Compared with patients with normal glucose homeostasis, IGT subjects had impaired insulin sensitivity, whereas insulin secretion was reduced only in those with IFG+IGT or DM.
Conclusions. IGM incidence is high in young adults with WS, suggesting the need of early screening and timed intervention. As in classical type 2 diabetes, impaired insulin sensitivity and β-cell dysfunction contribute, in this sequence, to progression to IGM and DM
The 17th International Conference on Scientometrics and Informetrics
[No abstract available
The effect of multidisciplinary collaborations on research diversification
This work verifies whether research diversification by a scientist is in some
measure related to their collaboration with multidisciplinary teams. The
analysis considers the publications achieved by 5300 Italian academics in the
sciences over the period 2004-2008. The findings show that a scientist's
outputs resulting from research diversification are more often than not the
result of collaborations with multidisciplinary teams. The effect becomes more
pronounced with larger and particularly with more diversified teams. This
phenomenon is observed both at the overall level and for the disciplinary
macro-areas
Glazed roman ceramic. A multi-analytical approach
A multi-analytical approach has been applied to characterize ancient glazed ceramics
from the archaeological sites of Magna Mater temple and Domus Tiberiana on the
Palatine Hill (Rome, Italy) dated between the 3rd and the early 5th century AD. The
aim of this work is to investigate the production technologies of the ceramic body and
the glazed coating and to explore the nature and the provenance of the raw materials.
Optical microscopy (OM), Fourier transform infrared spectroscopy (FTIR) and X-ray
powder diffraction (XRPD) results showed that the ceramic body is composed by
quartz, K-feldspar and plagioclase, fragments of igneous and sedimentary rocks. The
firing temperature was estimated at about 900-1000 °C, in uncontrolled atmosphere
conditions. The mineralogical assemblage of the ceramic body is consistent with a local
source of the raw materials. The results of electron microscopy coupled with energy
dispersive X-ray spectroscopy (SEM-EDS) showed that the glazes contain different Si/
Pb ratios. In addition, X-ray fluorescence (XRF) detected the presence of Sn although
its concentration does not allow defining the studied samples as tin-glazed ceramics.
However, the occurrence of this element indicates an atypical Roman production, never
recognized before in coeval samples from other archaeological sites
CleAir monitoring system for particulate matter. A case in the Napoleonic Museum in Rome
Monitoring the air particulate concentration both outdoors and indoors is becoming a more relevant issue in the past few decades. An innovative, fully automatic, monitoring system called CleAir is presented. Such a system wants to go beyond the traditional technique (gravimetric analysis), allowing for a double monitoring approach: the traditional gravimetric analysis as well as the optical spectroscopic analysis of the scattering on the same filters in steady-state conditions. The experimental data are interpreted in terms of light percolation through highly scattering matter by means of the stretched exponential evolution. CleAir has been applied to investigate the daily distribution of particulate matter within the Napoleonic Museum in Rome as a test case
Authorship analysis of specialized vs diversified research output
The present work investigates the relations between amplitude and type of
collaboration (intramural, extramural domestic or international) and output of
specialized versus diversified research. By specialized or diversified
research, we mean within or beyond the author's dominant research topic. The
field of observation is the scientific production over five years from about
23,500 academics. The analyses are conducted at the aggregate and disciplinary
level. The results lead to the conclusion that in general, the output of
diversified research is no more frequently the fruit of collaboration than is
specialized research. At the level of the particular collaboration types,
international collaborations weakly underlie the specialized kind of research
output; on the contrary, extramural domestic and intramural collaborations are
weakly associated with diversified research. While the weakness of association
remains, exceptions are observed at the level of the individual disciplines
Analysis of the seismic site effects along the ancient Via Laurentina (Rome)
This paper presents an evaluation of the Local Seismic Response (LSR)
along the route of the ancient Roman road Via Laurentina, which has
been exposed in several areas of southwest Rome over the last decade
during the construction of new buildings and infrastructures. It is
an example of LSR analysis applied to ancient and archaeological
sites located in alluvial valleys with some methodological inferences
for the design of infrastructure and urban planning. Since the ancient
road does not cross the alluvial valley (namely the Fosso di Vallerano
Valley) normal to its sides, it was not possible to directly perform
2D numerical modelling to evaluate the LSR along the road route.
Therefore, outputs of 2D numerical models, obtained along three cross
sections that were normal oriented respect to the valley, were projected
along the route of the Via Laurentina within a reliable buffer attributed
according to an available high-resolution geological model of the
local subsoil. The modelled amplification functions consider physical
effects due to both the 2D shape of the valley and the heterogeneities
of the alluvial deposits. The 1D and 2D amplification functions were
compared to output that non-negligible effects are related to the narrow
shape of the fluvial valley and the lateral contacts between the
lithotecnical units composing the alluvial fill. The here experienced
methodology is suitable for applications to the numerical modelling of
seismic response in case of linear infrastructures (i.e., roads, bridges,
railways) that do not cross the natural system along physically characteristic
directions (i.e. longitudinally or transversally)
On tit for tat: Franceschini and Maisano versus ANVUR regarding the Italian research assessment exercise VQR 2011-2014
The response by Benedetto, Checchi, Graziosi & Malgarini (2017) (hereafter
"BCG&M"), past and current members of the Italian Agency for Evaluation of
University and Research Systems (ANVUR), to Franceschini and Maisano's ("F&M")
article (2017), inevitably draws us into the debate. BCG&M in fact complain
"that almost all criticisms to the evaluation procedures adopted in the two
Italian research assessments VQR 2004-2010 and 2011-2014 limit themselves to
criticize the procedures without proposing anything new and more apt to the
scope". Since it is us who raised most criticisms in the literature, we welcome
this opportunity to retrace our vainly "constructive" recommendations, made
with the hope of contributing to assessments of the Italian research system
more in line with the state of the art in scientometrics. We see it as equally
interesting to confront the problem of the failure of knowledge transfer from
R&D (scholars) to engineering and production (ANVUR's practitioners) in the
Italian VQRs. We will provide a few notes to help the reader understand the
context for this failure. We hope that these, together with our more specific
comments, will also assist in communicating the reasons for the level of
scientometric competence expressed in BCG&M's heated response to F&M's
criticism
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