189 research outputs found
Room for space in agencification reforms: A tale of three Italian museums
The debate on agencification in the public sector has traditionally overlooked the influence of space on how autonomy unfolds in practice. Starting with the contention that organizing and space are interweaved, the study analyses the early stages of the agencification process of three Italian museums and reveals that space is a constraint to, and an enabler of, de facto autonomy for newly created entities. Space is a constraint when spatial changes are temporally misaligned with the agencification process, including directorship cycles. On the other hand, space enables de facto autonomy, as it is purposely modified to accommodate new demands and needs by newly appointed managers. The paper maintains that policy makers and site managers should seriously consider space when dealing with agencification reforms, paying attention to the revenue and cost implications of spatial solutions, and the areas of responsibility concerning buildings and objects
Study of Black Core, ceramic tile’s defect, by a multi technique approach
The traditional ceramic industrial production, for most of its applications, i.e. Ceramic Tiles, Heavy Clay Products, Tableware and Sanitaryware, is often affected by the formation, during the firing process, of a dark color core, normally named “Black Core”, that can represent an aesthetical and technological problem.
The true nature of this defect was never clearly stated, but it is known to be due to the presence of chromophores, like Iron, and organic or reducing materials, combined with a lack of permeability of the unfired body.
A novel, mullti-approach study was made by XRD, XRF, SEM-EDS, FTIR and Mossbauer Spectroscopy, and by micro Raman spectroscopy and mapping, with the aim to clarify the morphology, the composition and the Iron oxidation state of this inner layer.
Possible solutions were suggested, by the addition to the recipe of proper additives
A MULTI-ANALYTICAL APPROACH FOR THE CHARACTERIZATION OF POWDERS COMING FROM POMPEII ARCHAEOLOGICAL SITE
Archaeometric analysis of painted tombstones (IV century BC) from Paestum (Italy)
50 graves, painted by fresco technique, have been analyzed by micro-Raman Spectroscopy and X-Ray Fluorescence in order to identify the artists’ palettes and attempt to differentiate various workshops.
Before sampling, points of interest were selected by a preliminary in situ XRF analysis. Then, samples were collected and analyzed in laboratory by micro-Raman Spectroscopy.
We sampled from Green, Blue, Red, Yellow and Black areas, from every grave, and created a database where we put together analytical and historical data.
Red and Yellow are obtained by Hematite and Goethite, respectively; Blue is always Egyptian Blue; Black contains Carbon or Magnetite, or a mix of them.
Interesting data came from Green areas. We found 2 mixtures: Egyptian Blue and Yellow Ochre, or Yellow Ochre and Carbon. This peculiarity could be useful in the future for the discrimination of the different workshops
Differences among Three Branded Formulations of Hyaluronic Acid: Data from Environmental Scanning Electron Microscope Profile, Rheology Behavior and Biological Activity
Background: This study has analysed the viscosupplemental proprieties of three
commercially available formulations of Hyaluronic Acid (HA) suspension (F1: Synvisc,
Hylan G-F 20; F2: Hyalgan; F3: Donegal HA 2.0), which differ in composition, Molecular
Weight (MW) and HA content.
Methods: Analyses were conducted using rheology measurements and Environmental
Scanning Electron Microscope (ESEM). The capacity of the three tested formulations to
inhibit specific Metalloproteases (MMPs) was also evaluated.
Results: F1 is the only sample showing viscoelastic properties but may have increased
immunogenicity attributable to the subsequent chemical cross-linking process that
enhances the MW. F2 and F3 show a lower viscosity compared to F1. F2 has the lowest
viscosity at low shear rate, the lower independence from the oscillatory stress and a
solution-like rheology behaviour. F3 display a solution behaviour. However, unlike F2, F3
crossover point falls in the middle of the frequency range of interest showing a considerable
rheological behaviour. The internal structure of F3 (pseudo-spongy thick filaments)
suggests that it has the ability to interact with a great water content. The crossover points
of the examined samples clearly reveal their different rheological behaviour, allowing their
classification in gel-like or solution-like materials. F3 has higher ability in inhibiting MMP-
2 and MMP-9 activity compared to F1 and F2, probably due to its specific MW and/or
higher HA concentration.
Conclusion: The three tested HA formulations differ in rheological properties and
inhibition of MMP-2 and MMP-9 activity. F3 seems to be the most appropriate formulation
for the treatment of osteoarthritis and rheumatoid arthritis
Band dispersion in the deep 1s core level of graphene
Chemical bonding in molecules and solids arises from the overlap of valence
electron wave functions, forming extended molecular orbitals and dispersing
Bloch states, respectively. Core electrons with high binding energies, on the
other hand, are localized to their respective atoms and their wave functions do
not overlap significantly. Here we report the observation of band formation and
considerable dispersion (up to 60 meV) in the core level of the carbon
atoms forming graphene, despite the high C binding energy of 284
eV. Due to a Young's double slit-like interference effect, a situation arises
in which only the bonding or only the anti-bonding states is observed for a
given photoemission geometry.Comment: 12 pages, 3 figures, including supplementary materia
Atomic Undercoordination in Ag Islands on Ru(0001) Grown via Size-Selected Cluster Deposition: An Experimental and Theoretical High-Resolution Core-Level Photoemission Study
The possibility of depositing precisely mass-selected Ag clusters (Ag-1, Ag-3, and Ag-7) on Ru(0001) was instrumental in determining the importance of the in-plane coordination number (CN) and allowed us to establish a linear dependence of the Ag 3d(5/2) core-level shift on CN. The fast cluster surface diffusion at room temperature, caused by the low interaction between silver and ruthenium, leads to the formation of islands with a low degree of ordering, as evidenced by the high density of low-coordinated atomic configurations, in particular CN = 4 and 5. On the contrary, islands formed upon Ag-7 deposition show a higher density of atoms with CN = 6, thus indicating the formation of islands with a close-packed atomic arrangement. This combined experimental and theoretical approach, when applied to clusters of different elements, offers the perspective to reveal nonequivalent local configurations in two-dimensional (2D) materials grown using different building blocks, with potential implications in understanding electronic and reactivity properties at the atomic level
Spotting local environments in self-assembled monolayer-protected gold nanoparticles
Organic-inorganic (O-I) nanomaterials are versatile platforms for an incredible high number of applications, ranging from heterogeneous catalysis, molecular sensing, cell targeting, imaging, cancer diagnosis and therapy, just to name a few. Much of their potential stems from the unique control of organic environments around inorganic sites within a single O-I nanomaterial, which allows for new properties inaccessible using purely organic or inorganic materials. Structural and mechanistic characterization plays a key role in understanding and rationally designing such hybrid nanoconstructs. Here, we introduce a general methodology to identify and classify local (supra)molecular environments in an archetypal class of O-I nanomaterials, i.e. self-assembled monolayer-protected gold nanoparticles (SAM-AuNPs). By using an atomistic machine-learning guided workflow based on the Smooth Overlap of Atomic Positions (SOAP) descriptor, we analyze a collection of chemically different SAM-AuNPs, and detect and compare local environments in a way that is agnostic and automated, i.e. with no need of a-priori information and minimal user intervention. In addition, the computational results coupled with experimental electron spin resonance measurements prove that is possible to have more than one local environment inside SAMs, being thickness of the organic shell and solvation primary factors in determining number and nature of multiple co-existing environments. These indications are extended to complex mixed hydrophilic-hydrophobic SAMs. This work demonstrates that it is possible to spot out and compare local molecular environments in SAM-AuNPs exploiting atomistic machine-learning approaches, establishes ground rules to control them, and holds the potential for rational design of O-I nanomaterials instructed from data
Addendum: Long-term Treatment Benefits and Prolonged Efficacy of OnabotulinumtoxinA in Patients Affected by Chronic Migraine and Medication Overuse Headache over 3 Years of Therapy
Inter-society consensus document on treatment and prevention of bronchiolitis in newborns and infants
Acute bronchiolitis is the leading cause of lower respiratory tract infection and hospitalization in children less than 1 year of age worldwide. It is usually a mild disease, but some children may develop severe symptoms, requiring hospital admission and ventilatory support in the ICU. Infants with pre-existing risk factors (prematurity, bronchopulmonary dysplasia, congenital heart diseases and immunodeficiency) may be predisposed to a severe form of the disease.
Clinical diagnosis of bronchiolitis is manly based on medical history and physical examination (rhinorrhea, cough, crackles, wheezing and signs of respiratory distress). Etiological diagnosis, with antigen or genome detection to identify viruses involved, may have a role in reducing hospital transmission of the infection.
Criteria for hospitalization include low oxygen saturation (<90-92%), moderate-to-severe respiratory distress, dehydration and presence of apnea. Children with pre-existing risk factors should be carefully assessed.
To date, there is no specific treatment for viral bronchiolitis, and the mainstay of therapy is supportive care. This consists of nasal suctioning and nebulized 3% hypertonic saline, assisted feeding and hydration, humidified O2 delivery. The possible role of any pharmacological approach is still debated, and till now there is no evidence to support the use of bronchodilators, corticosteroids, chest physiotherapy, antibiotics or antivirals. Nebulized adrenaline may be sometimes useful in the emergency room. Nebulized adrenaline can be useful in the hospital setting for treatment as needed. Lacking a specific etiological treatment, prophylaxis and prevention, especially in children at high risk of severe infection, have a fundamental role. Environmental preventive measures minimize viral transmission in hospital, in the outpatient setting and at home. Pharmacological prophylaxis with palivizumab for RSV bronchiolitis is indicated in specific categories of children at risk during the epidemic period.
Viral bronchiolitis, especially in the case of severe form, may correlate with an increased incidence of recurrent wheezing in pre-schooled children and with asthma at school age.
The aim of this document is to provide a multidisciplinary update on the current recommendations for the management and prevention of bronchiolitis, in order to share useful indications, identify gaps in knowledge and drive future research
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