714 research outputs found
Deamidation at Asparagine and Glutamine As a Major Modification upon Deterioration/Aging of Proteinaceous Binders in MuralPaintings
Proteomic strategies are herein proved to be a
complementary approach to the well established amino acid
composition analysis for the characterization of the aging and
deterioration phenomena occurring to proteinaceous materials
in works-of-art. Amino acid analyses on several samples demonstrated
that proteins in the frescoes from the Camposanto
Monumentale in Pisa are deteriorated as revealed by the
decrease in Met, Lys, and Tyr content and by the presence in
all the samples of amino malonic acid as a result of Ser, Phe, and
Cys oxidation. Proteomic analysis identified deamidation at Asn
and Gln as a further major event occurred. This work paves the
way to the exploitation of proteomic strategies for the investigation
of the molecular effects of aging and deterioration in
historical objects. Results show that proteomic searches for
deamidation by liquid chromatography-tandem mass spectrometry
(LC-MS/MS) could constitute a routine analysis for paintings or any artistic and historic objects where proteins are present.
Peptides that can be used as molecular markers when casein is present were identified
Biosynthesis of Mitochondrial Porin and Insertion into the Outer Mitochondrial Membrane of Neuruspora crassa
Mitochondrial porin, the major protein of the outer mitochondrial membrane is synthesized by free cytoplasmic polysomes. The apparent molecular weight of the porin synthesized in homologous or heterologous cell-free systems is the same as that of the mature porin. Transfer in vitro of mitochondrial porin from the cytosolic fraction into the outer membrane of mitochondria could be demonstrated. Before membrane insertion, mitochondrial porin is highly sensitive to added proteinase; afterwards it is strongly protected. Binding of the precursor form to mitochondria occurs at 4°C and appears to precede insertion into the membrane. Unlike transfer of many precursor proteins into or across the inner mitochondrial membrane, assembly of the porin is not dependent on an electrical potential across the inner membrane
Migrant pathways to community mental health centres in Italy.
Background: Many studies indicate that migrants in western countries have limited access to and low utilization of community mental health centres (CMHCs) despite the high prevalence of mental disorders. Aims: We aimed to compare migrant pathways to care across four CMHCs located in different Italian provinces and to identify pathway to care predictors. Methods: Migrants attending the four CMHCs between 1 July 1999 and 31 December 2007 were included in the study. Data were gathered retrospectively from clinical data sets and chart review. Results: Five hundred and eleven (511) migrants attended the four CMHCs, 61% were referred by GPs or other health services and 39% followed non-medical pathways to care (self-referral or through social and voluntary organizations), with important site variations. Younger age and being married were predictors of medical pathways to care; lacking a residence permit and having a diagnosis of substance abuse were related to non-medical pathways. Conclusions: Pathways to CMHCs are complex and influenced by many factors. Non-medical pathways to care seem to be frequent among migrants in Italy. More attention should be paid to developing psychiatric consultation liaison models that also encompass the social services and voluntary organizations
Migrant pathways to community mental health centres in Italy.
Background: Many studies indicate that migrants in western countries have limited access to and low utilization of community mental health centres (CMHCs) despite the high prevalence of mental disorders. Aims: We aimed to compare migrant pathways to care across four CMHCs located in different Italian provinces and to identify pathway to care predictors. Methods: Migrants attending the four CMHCs between 1 July 1999 and 31 December 2007 were included in the study. Data were gathered retrospectively from clinical data sets and chart review. Results: Five hundred and eleven (511) migrants attended the four CMHCs, 61% were referred by GPs or other health services and 39% followed non-medical pathways to care (self-referral or through social and voluntary organizations), with important site variations. Younger age and being married were predictors of medical pathways to care; lacking a residence permit and having a diagnosis of substance abuse were related to non-medical pathways. Conclusions: Pathways to CMHCs are complex and influenced by many factors. Non-medical pathways to care seem to be frequent among migrants in Italy. More attention should be paid to developing psychiatric consultation liaison models that also encompass the social services and voluntary organizations
Community Structure of Terrestrial Invertebrates Inhabiting a Tidal Marsh Islet in the Mediterranean Sea (Gulf of Gabes, Tunisia)
The composition of the terrestrial arthropod community of a tidal marsh islet in the Gulf of Gabes (Tunisia) was studied during two seasons (spring, autumn). The study was conducted on a small islet located in an area where the highest tidal excursions of the Mediterranean occur. Standard trapping methods (pitfall traps, mobile cages) were used to evaluate specie richness and abundance in different areas of the islet. Diversity indices were calculated for coleopterans and isopods alone. The structure of the arthropod community varied a great deal from one season to the other and differences were found when seaward areas were compared with landward ones. El Bessila presented a particularly rich beetle community whereas only few isopod species occurred. The moderately high diversity levels found for the beetle indicate the influence of the high tidal excursions in modelling the structure of the community
Field evidence for the upwind velocity shift at the crest of low dunes
Wind topographically forced by hills and sand dunes accelerates on the upwind
(stoss) slopes and reduces on the downwind (lee) slopes. This secondary wind
regime, however, possesses a subtle effect, reported here for the first time
from field measurements of near-surface wind velocity over a low dune: the wind
velocity close to the surface reaches its maximum upwind of the crest. Our
field-measured data show that this upwind phase shift of velocity with respect
to topography is found to be in quantitative agreement with the prediction of
hydrodynamical linear analysis for turbulent flows with first order closures.
This effect, together with sand transport spatial relaxation, is at the origin
of the mechanisms of dune initiation, instability and growth.Comment: 13 pages, 6 figures. Version accepted for publication in
Boundary-Layer Meteorolog
Biogenesis of mitochondrial porin
We review here the present knowledge about the pathway of import and assembly of porin into mitochondria and compare it to those of other mitochondrial proteins. Porin, like all outer mitochondrial membrane proteins studied so far is made as a precursor without a cleavble lsquosignalrsquo sequence; thus targeting information must reside in the mature sequence. At least part of this information appears to be located at the amino-terminal end of the molecule. Transport into mitochondria can occur post-translationally. In a first step, the porin precursor is specifically recognized on the mitochondrial surface by a protease sensitive receptor. In a second step, porin precursor inserts partially into the outer membrane. This step is mediated by a component of the import machinery common to the import pathways of precursor proteins destined for other mitochondrial subcompartments. Finally, porin is assembled to produce the functional oligomeric form of an integral membrane protein wich is characterized by its extreme protease resistance
Reconstruction of the gravitational wave signal during the Virgo science runs and independent validation with a photon calibrator
The Virgo detector is a kilometer-scale interferometer for gravitational wave
detection located near Pisa (Italy). About 13 months of data were accumulated
during four science runs (VSR1, VSR2, VSR3 and VSR4) between May 2007 and
September 2011, with increasing sensitivity.
In this paper, the method used to reconstruct, in the range 10 Hz-10 kHz, the
gravitational wave strain time series from the detector signals is
described. The standard consistency checks of the reconstruction are discussed
and used to estimate the systematic uncertainties of the signal as a
function of frequency. Finally, an independent setup, the photon calibrator, is
described and used to validate the reconstructed signal and the
associated uncertainties.
The uncertainties of the time series are estimated to be 8% in
amplitude. The uncertainty of the phase of is 50 mrad at 10 Hz with a
frequency dependence following a delay of 8 s at high frequency. A bias
lower than and depending on the sky direction of the GW is
also present.Comment: 35 pages, 16 figures. Accepted by CQ
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