The effect of sintering atmosphere on the optical and structural properties of Cerium doped sol–gel silica was investigated. Two sets of xerogels with Ce concentration from 0 to 10
mol% were prepared ...and densified in different conditions. The effect of a post-densification rapid thermal treatment was also considered. Optical absorption measurements evidenced that in oxidizing conditions Cerium is preferably incorporated inside the silica matrix as Ce
4+ while the trivalent state is favoured by reducing conditions. Transmission electron microscopy images show rare-earth clusters formation whose nature was investigated by means of Raman, EDS and microdiffraction measurements. In order to evaluate the efficiency of the glasses as scintillating materials radio-luminescence measurements were carried out. A numerical fit of RL spectra showed the presence of two components peaking at 2.7 and 3.1
eV. After RTT, the relative intensity of the 3.1
eV component increases with Ce concentration.
Background
The aim of the study was to investigate the different B‐cell responses after a glucagon stimulation test (GST) versus mixed meal tolerance test (MMTT).
Methods
We conducted GST and MMTT in ...10 healthy people (aged 25‐40 years) and measured C‐peptide, gastric inhibitory peptide (GIP) and glucagon‐like peptide‐1 (GLP‐1) at different time points after the administration of 1 mg i.v. glucagon for GST or a liquid mixed meal for MMTT.
Results
The GST stimulated C‐peptide showed a mean increase of 147.1%, whereas the mean increase of MMTT stimulated C‐peptide was 99.82% (Δincrease = 47.2%). Maximum C‐peptide level reached with the MMTT was greater than that obtained with the GST (C‐pept max MMTT = 2.35 nmol/L vs C‐pep max GST = 1.9 nmol/L). A positive and linear correlation was found between the GST incremental area under the curve C‐peptide and the MMTT incremental area under the curve C‐peptide (r = 0.618, P = .05). After GST, there was no increment of GIP and glucagon like peptide‐1 levels compared to baseline levels. A positive and linear correlation between GIP and C‐peptide levels was observed only for the MMTT (r = 0.922, P = .008) indicating that in the GST, the C‐peptide response is independent of the incretin axis response.
Conclusions
Although the 2 stimulation tests may elicit a similar response in C‐peptide secretion, B‐cell response to MMTT depends on a functionally normal incretin axis. These results may have implications when investigating the B‐cell response in people with diabetes and for studies in which stimulated C‐peptide secretion is used as primary or secondary outcome for response to therapy.
Brandt iH026a plant growth regulator Nonomura, A. M.; Pedersen, A.; Brummel, D. P. ...
Photosynthetica,
03/2018, Letnik:
56, Številka:
1
Journal Article
Recenzirano
Odprti dostop
iH026a is a formulation containing a biochemical class of plant growth regulator that modulates glycoconjugation through the plant lectin cycle. While lectins are common to vascular plants, we ...observed, consistent with reversible binding of sugars from lectins, enhancements of quantities and qualities of various features, including significant enrichment of Brix soluble sugars compared to controls in cherry, grape, and melon in trials conducted in Arizona and California, USA.
Resumen Las lesiones que simulan tumores en el sistema musculoesquelético se definen como lesiones no neoplásicas benignas que pueden confundirse, tanto por la clínica como radiológicamente, con ...neoplasias. La etiología y las localizaciones anatómicas de las lesiones son variables, desde variantes normales hasta lesiones traumáticas, inflamatorias o metabólicas. Con un adecuado interrogatorio, una exhaustiva exploración física y una apropiada selección de métodos por imágenes, se pueden diferenciar las lesiones tumorales de las no tumorales. En los casos en que no se logra certeza diagnóstica se debe recurrir a la biopsia para descartar malignidad. Se analizan ocho casos del Comité de Tumores Óseos y Partes Blandas de nuestra institución con diagnósticos presuntivos de lesiones tumorales y biopsias negativas para células neoplásicas. La etiología de las lesiones de los ocho pacientes fue calcificación heterotópica con esclerosis ósea, lesión por estrés, hematoma organizado, absceso, infiltración de médula ósea con área respetada, remodelación ósea, cambios reparativos y esteatonecrosis.
Phase transformations at the nanoscale represent a challenging field of research, mainly in the case of nanocrystals (NCs) in a solid host, with size-effects and interactions with the matrix. Here we ...report the study of the structural evolution of γ-Ga
2
O
3
NCs in alkali-germanosilicate glass - a technologically relevant system for its light emission and UV-to-visible conversion - showing an evolution drastically different from the expected transformation of γ-Ga
2
O
3
into β-Ga
2
O
3
. Differential scanning calorimetry registers an irreversible endothermic process at ∼1300 K, well above the exothermic peak of γ-Ga
2
O
3
nano-crystallization (∼960 K) and below the melting temperature (∼1620 K). Transmission electron microscopy and X-ray diffraction data clarify that glass-embedded γ-Ga
2
O
3
NCs transform into LiGa
5
O
8
via
diffusion-driven kinetics of Li incorporation into NCs. At the endothermic peak, β-Ga
2
O
3
forms from LiGa
5
O
8
dissociation, following a nucleation-limited kinetics promoted by size-dependent order-disorder change between LiGa
5
O
8
polymorphs. As a result of the changes, modifications of UV-excited NC light emission are registered, with potential interest for applications.
We describe the evolution of γ-Ga
2
O
3
nanocrystals in alkali-germanosilicate glass, disclosing mechanisms of nanocrystal-matrix interaction
via
a diffusion-driven change, into LiGa
5
O
8
and β-Ga
2
O
3
formation by decomposition promoted by size-dependent order-disorder polymorphism.
Muon Radiography allows to map the density of a volcanic cone. It is based on the measurement of the attenuation of the flux of muons present in the cosmic radiation on the ground. The MU-RAY project ...has developed an innovative detector designed for the muon radiography. The main features are the low electric power consumption, robustness and transportability, good spatial resolution and muon time of flight measurement. A 1 m super(2) detector prototype has been constructed. and collected data at Mt. Vesuvius for approximately 1 month in spring 2013. A second campaign of measurement has been performed at the Puy de Dome, France, in the last four months of 2013. In this article the principles of muon radiography, the MU-RAY detector and the first results from the collected data will be described.
Multifocal motor neuropathy (MMN) is an immune-mediated disorder characterized by slowly progressive asymmetric muscle weakness and electrophysiological findings of motor conduction block. The ...immunological hypothesis for pathogenesis of MMN is supported by the association, in 30–80% of cases, with high title Anti-GM1 antibodies and positive response to intravenous immunoglobulin (IVIg) therapy. Ultrasound (US) is recently gaining a crucial role in the assessment of immune-related neuropathies. We report the clinical, electrophysiological and US follow-up of five cases of patients affected with MMN treated with IVIg. In two patients (male 44 years old, female 37 years old) who started IVIg treatment soon after onset, US demonstrated complete or partial normalization. Conversely, in the other three patients (two males 49 and 70 years old, female 48 years old) who started IVIg respectively four months, twenty years and 1 year after onset, we observed an incomplete clinical, electrophysiological and ultrasound IVIg response.
An increase in the number of partially sighted people is one of the effects of population ageing. These people have great difficulties in gathering wayfinding information to move independently in an ...unfamiliar environment. Guide paths based on the luminance contrast between a strip and surrounding surfaces can be an effective device for mitigating these difficulties, but information provided by the scientific literature on guide paths cannot be usefully applied to the naturally coloured paving materials most commonly found in pedestrian urban spaces. This paper presents a simplified method for measuring the luminance contrast between a guide strip and its background using combinations of naturally coloured paving materials.
PDF
