Space weathering, reddening and gardening of asteroids: A complex problem

The association of ordinary chondrites and their parent bodies through their visible and near infrared spectra is still a debate. In fact, many asteroids show reddened spectra, while the ordinary chondrites do not. In the framework of the space weathering of asteroid surfaces, the interpretation of the reddening, darkening, and depletion of band depths is not as simple as previously described. We present a summary of the recent results in the study of the reddening of the spectra. To date, different mechanisms have been proposed to explain some properties of spectra, but a complete scenario capable of reproducing the whole set of observations is still missing. (C) 2007 COSPAR. Published by Elsevier Ltd. All rights reserved

Biological niches within human calcified aortic valves. Towards understanding of the pathological biomineralization process

Despite recent advances, mineralization site, its microarchitecture, and composition in calcific heart valve remain poorly understood. A multiscale investigation, using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectrometry (EDS), from micrometre up to nanometre, was conducted on human severely calcified aortic and mitral valves, to provide new insights into calcificationp rocess. Our aim was to evaluate the spatial relationship existing between bioapatite crystals, their local growing microenvironment, and the presence of a hierarchical architecture. Here we detected the presence of bioapatite crystals in two different mineralization sites that suggest the action of two different growth processes:a pathological crystallization process that occurs in biological niches and is ascribed to a purely physicochemical process and a matrix- mediated mineralized process in which the extracellular matrix acts as the template for a site-directed nanocrystals nucleation. Different shapes of bioapatite crystallization were observed at micrometer scale in each microenvironment but at the nanoscale level crystals appear to be made up by the same subunit

Archeometrical Analysis for the Characterization of Mortars from Ostia Antica

AbstractThe aim of the study is to provide, through the characterization of the mortar samples and the relative raw materials, useful information in order to define the stages of construction, the workers technological and archaeological knowledge. The study is an interdisciplinary approach carried out by different analysis techniques in order to define the mineral-petrographic composition and highlight the differences among the various samples. Mortars are present in all the walls, except dry ones, as a bedding material and as a coating. The mortars may be regarded as markers for excellence, because they must be prepared at the time of their use, during the construction of the masonry, and cannot be re-used after their hardening and socket. Furthermore, the production of mortars in the past depended on the availability of raw materials in situ thus establishing a strong and direct correlation between the origin and use.The chemical and petrographic study of the subtle differences and composition of the mortar makes it possible to use this material as an excellent timeline if the supply of building materials varies over time. Mortars, for these reasons, play two key roles in archaeological survey: an absolutely priority for the correct determination of the contours of Stratigraphic Units; the role of the typological class very representative and very useful for making comparisons between different parts of the building and connecting between them the activities of the individual site

A multi-scale investigation of biological niches within human calcified aortic valves helps to understand the pathological biomineralization process

Calcific aortic valve stenosis (CAVS) is the most common form of heart valve disease in the industrialized countries, being an important public health problem [1]. Ectopic calcifications within aortic valve leaflets are strictly associated with CAVS, interfering with cusps opening, they lead to ventricular outflow obstruction [2]. Up to date no proven medical therapy stops CAVS course progression, so valve replacement is the only possible treatment of severe CAVS. Unfortunately, the degenerative valve calcification process, affects also bioprosthetic implants [3]. Being the molecular mechanisms leading to valve calcification still not understood, our aim was to carry on a multi-scale investigation using Scanning Electron Microscopy, Transmission Electron Microscopy and Energy Dispersive X-ray Spectrometry, to provide new insights into calcification process. Severely calcified aortic (tricuspid type, n = 29; bicuspid type, n = 3) and mitral valves (n = 4) were obtained from patients of both sexes (males=25) and different ages (mean age 72±10, range 41-90 years old) undergoing valve replacement due to severe aortic and mitral valve stenosis. We detected bioapatite crystals in two different mineralization sites: niches and extracellular matrix. This suggests the action of two different growth processes: the first occurs in biological niches and it is ascribed to a purely physico-chemical process; the second has the extracellular matrix acting ass the template for a site-directed nanocrystals nucleation. Different shapes of bioapatite crystallization were observed at micrometer scale in each microenvironment but at the nanoscale level crystals appear made up by the same subunits. We suggest that bioapatite nanocrystals in heart valve may activate a strong inflammatory process leading to irreversible pathological condition that, once activated,may aggravate the inflammatory response against bioapatite nanocrystals leading to a severe calcification process

FE-SEM and VP-SEM imaging of human calcified aortic valves: conventional vs Ionic Liquid innovative techniques

Conventional FE-SEM protocol for calcified aortic valves (CAVs) consist of following steps: glutaraldehyde fixation, OsO4 post-fixation, dehydration in alcohol series, critical point drying and finally sputter coating. CAVs can be observed in their native state (fixed in glutaraldehyde with and without post-fixation in OsO4) by Variable Pressure-SEM (range 6- 650 Pa). Gas presence allows an inferior resolution (low signal to noise ratio), however there is the possibility to perform EDS elemental analysis without background noise due to sputter coating. Recently Ionic liquids (IL, salts in the liquid state at room temperature) were used as suppliers of electronic conductivity with insulating properties, so we have tested their ability to replace sputter coating on CAVs in high vacuum condition. Samples fixed in glutharaldehyde 2,5% in PBS with and without OsO4 post-fixation treated with ionic liquid (Hitachi HILEM® IL 1000) were compared with samples treated with conventional FE-SEM procedures. Several IL concentration (range from 5% to 20%) were tested, different operating voltages (range from 3 to 20Kv) were used. This novel technology requires a high degree of customization for each sample type. In our opinion fixation in glutaraldehyde with OsO4 post-fixation is recommended to preserve finest details, moreover residual liquid elimination is important to increase resolution and avoid beam interference as linear markings. Setting of a proper accelerating voltage allows to correctly visualize the surface topography. Processing CAVs with IL with respect to conventional FE-SEM is useful for several reasons. Mainly this method is time saving (and cost saving), secondary the same sample can be processed for transmission electron microscopy after SEM observations (allowing correlative microscopy), finally EDS can be performed without background noise due to sputter coating. Perhaps now this technique can not completely replaces the conventional SEM in terms of resolution but in our opinion rapid technical improvement can further reduce this gap

Structural Properties of Macrodontain I, a Cysteine Protease from Pseudananas macrodontes (Morr.) Harms (Bromeliaceae)

The primary structure of macrodontain I, a peptidase from Pseudananas macrodontes fruits, was determined using Edman's degradation. The enzyme is a non-glycosylated peptidase composed by 213 amino acids with a calculated molecular weight of 23,486.18 Da, pI value 6.99, and a molar extinction coefficient at 280 nm of 61,685 M-1 cm-1. The alignment of the sequence of macrodontain I with those cysteine peptidases from species belonging to the family Bromeliaceae showed the highest identity degree (87.74%) against fruit bromelain. A remarkable fact is that all these peptidase sequences show two Met contiguous residues (Met121 and 122) and the nonapeptide VPQSIDWRD located in the mature N-terminal region. Residues Cys26 and His159, which constitute the catalytic dyad in all cysteine peptidases, as well as active site residues Gln20 and Asn176, characteristic of Clan C1A, are conserved in macrodontain I. The 3-D model suggests that the enzyme belongs to the α + β class of proteins, with two disulfide bridges (Cys23-Cys63 and Cys57-Cys96) in the α domain, while the β domain is stabilized by another disulfide bridge (Cys153-Cys201). Further, we were able to establish that the cysteine peptidases from P. macrodontes are involved in the anti-inflammatory activity.Facultad de Ciencias Exacta

Managing the link and strengthening transition from child to adult mental health Care in Europe (MILESTONE): Background, rationale and methodology

Background: Transition from distinct Child and Adolescent Mental Health (CAMHS) to Adult Mental Health Services (AMHS) is beset with multitude of problems affecting continuity of care for young people with mental health needs. Transition-related discontinuity of care is a major health, socioeconomic and societal challenge globally. The overall aim of the Managing the Link and Strengthening Transition from Child to Adult Mental Health Care in Europe (MILESTONE) project (2014-19) is to improve transition from CAMHS to AMHS in diverse healthcare settings across Europe. MILESTONE focuses on current service provision in Europe, new transition-related measures, long term outcomes of young people leaving CAMHS, improving transitional care through 'managed transition', ethics of transitioning and the training of health care professionals. Methods: Data will be collected via systematic literature reviews, pan-European surveys, and focus groups with service providers, users and carers, and members of youth advocacy and mental health advocacy groups. A prospective cohort study will be conducted with a nested cluster randomised controlled trial in eight European Union (EU) countries (Belgium, Croatia, France, Germany, Ireland, Italy, Netherlands, UK) involving over 1000 CAMHS users, their carers, and clinicians. Discussion: Improving transitional care can facilitate not only recovery but also mental health promotion and mental illness prevention for young people. MILESTONE will provide evidence of the organisational structures and processes influencing transition at the service interface across differing healthcare models in Europe and longitudinal outcomes for young people leaving CAMHS, solutions for improving transitional care in a cost-effective manner, training modules for clinicians, and commissioning and policy guidelines for service providers and policy makers

Transition from Child and Adolescent to Adult Mental Health Services in Young People with Depression: On What Do Clinicians Base their Recommendation?

BACKGROUND: Clinicians in Child and Adolescent Mental Healthcare Services (CAMHS) face the challenge to determine who is at risk of persistence of depressive problems into adulthood and requires continued treatment after reaching the CAMHS upper age limit of care-provision. We assessed whether risk factors for persistence were related to CAMHS clinicians’ transition recommendations. METHODS: Within the wider MILESTONE cohort study, 203 CAMHS users were classified with unipolar depressive disorder by their clinician, and 185 reported clinical levels of depressive problems on the DSM-oriented Depressive Problems scale of the Achenbach Youth Self Report. Logistic regression models were fitted to both subsamples to assess the relationship between clinicians’ transition recommendations and risk factors for persistent depression. RESULTS: Only clinicianrated severity of psychopathology was related to a recommendation to continue treatment for those classified with unipolar depressive disorder (N = 203; OR = 1 45, 95% CI (1.03–2.03), p = 044) and for those with self-reported depressive problems on the Achenbach DSM-oriented Depressive Problems scale (N = 185; OR = 1 62, 95% CI (1.12–2.34), p = 012). CONCLUSION: Transition recommendations and need for continued treatment are based on clinical expertise, rather than self-reported problems and needs

Validation of the Transition Readiness and Appropriateness Measure (TRAM) for the Managing the Link and Strengthening Transition from Child to Adult Mental Healthcare in Europe (MILESTONE) study

OBJECTIVE:Young people moving from child and adolescent mental health services (CAMHS) to adult mental health services (AMHS) are faced with significant challenges. To improve this state of affairs, there needs to be a recognition of the problem and initiatives and an urgent requirement for appropriate tools for measuring readiness and outcomes at the transfer boundary (16-18 years of age in Europe). The objective of this study was to develop and validate the Transition Readiness and Appropriateness Measure (TRAM) for assessing a young person's readiness for transition, and their outcomes at the transfer boundary. DESIGN:MILESTONE prospective study. SETTING:Eight European Union (EU) countries participating in the EU-funded MILESTONE study. PARTICIPANTS:The first phase (MILESTONE validation study) involved 100 adolescents (pre-transition), young adults (post-transition), parents/carers and both CAMHS and AMHS clinicians. The second phase (MILESTONE cohort study and nested cluster randomised trial) involved over 1000 young people. RESULTS:The development of the TRAM began with a literature review on transitioning and a review of important items regarding transition by a panel of 34 mental health experts. A list of 64 items of potential importance were identified, which together comprised the TRAM. The psychometric properties of the different versions of the TRAM were evaluated and showed that the TRAM had good reliability for all versions and low-to-moderate correlations when compared with other established instruments and a well-defined factor structure. The main results of the cohort study with the nested cluster randomised trial are not reported. CONCLUSION:The TRAM is a reliable instrument for assessing transition readiness and appropriateness. It highlighted the barriers to a successful transition and informed clinicians, identifying areas which clinicians on both sides of the transfer boundary can work on to ease the transition for the young person. TRIAL REGISTRATION NUMBER:ISRCTN83240263 (Registered 23 July 2015), NCT03013595 (Registered 6 January 2017); Pre-results

The importance of clinicians' and parents' awareness of suicidal behaviour in adolescents reaching the upper age limit of their mental health services in Europe

Background: To study clinicians' and parents' awareness of suicidal behaviour in adolescents reaching the upper age limit of their Child and Adolescent Mental Health Service (CAMHS) and its association with mental health indicators, transition recommendations and mental health service (MHS) use. Methods: 763 CAMHS users from eight European countries were assessed using multi-informant and standardised assessment tools at baseline and nine months follow-up. Separate ANCOVA's and pairwise comparisons were conducted to assess whether clinicians' and parents' awareness of young people's suicidal behaviour were associated with mental health indicators, clinician's recommendations to continue treatment and MHS use at nine months follow-up. Results: 53.5 % of clinicians and 56.9 % of parents were unaware of young people's self-reported suicidal behaviour at baseline. Compared to those whose clinicians/parents were aware, unawareness was associated with a 72–80 % lower proportion of being recommended to continue treatment. Self-reported mental health problems at baseline were comparable for young people whose clinicians and parents were aware and unaware of suicidal behaviour. Clinicians' and parents' unawareness were not associated with MHS use at follow-up. Limitations: Aspects of suicidal behaviour, such as suicide ideation, -plans and -attempts, could not be distinguished. Few young people transitioned to Adult Mental Health Services (AMHS), therefore power to study factors associated with AMHS use was limited. Conclusion: Clinicians and parents are often unaware of suicidal behaviour, which decreases the likelihood of a recommendation to continue treatment, but does not seem to affect young people's MHS use or their mental health problems