High-frequency dielectric spectroscopy of batio3 core - silica shell nanocomposites: Problem of interdiffusion

Three types of BaTiO3 core - amorphous nano-shell composite ceramics were processed from the same core-shell powder by standard sintering, spark-plasma sintering and two-step sintering techniques and characterized by XRD, HRSEM and broad-band dielectric spectroscopy in the frequency range 10^3 - 10^13 Hz including the THz and IR range. The samples differed by porosity and by the amount of interdiffusion from the cores to shells, in correlation with their increasing porosity. The dielectric spectra were also calculated using suitable models based on effective medium approximation. The measurements revealed a strong dielectric dispersion below the THz range, which cannot be explained by the modeling, and whose strength was in correlation with the degree of interdiffusion. We assigned it to an effect of the interdiffusion layers, giving rise to a strong interfacial polarization. It appears that the high-frequency dielectric spectroscopy is an extremely sensitive tool for detection of any gradient layers and sample inhomogeneities even in dielectric materials with negligible conductivity

Post-traumatic malunion of the proximal phalanx of the finger. Medium-term results in 24 cases treated by "in situ" osteotomy

We report the clinical and radiographic medium-term results obtained for 20 patients (24 fingers) treated surgically for post-traumatic malunion of the proximal phalanx of the finger. In all cases we performed a corrective osteoclasia or osteotomy at the site of malunion, followed by miniplate and screw fixation or by screw fixation only. The corrective osteoclasia was performed when malalignment was addressed within six weeks after injury. Two patients who had two fractures underwent additional surgery (tenolysis and/or capsulolysis) to improve function and ROM. At the final follow-up, at a mean of 24 months after corrective surgery, good or excellent clinical and radiographic results were obtained in all the patients. The pseudoclaw deformity disappeared in all cases in which a volar angulation deformity was present. An average improvement of about 30% in the range of motion of the MP and PIP joints was observed; only 4 patients complained of mild pain at the maximum degrees of articular excursion of the MP and PIP joints. All the patients presented an improvement in grip strength. The mean DASH score in our series was 5 points. In two of the four cases treated by an intra-articular corrective osteotomy, mild radiographic signs of osteoarthritis at the MP joint were present. The data for this study confirm that "in situ" osteotomy stabilized by miniplates and/or screws is an effective procedure to correct post-traumatic malunions of the proximal phalanges of the fingers

Simultaneous Bilateral Flexion-Type Salter-Harris II Fractures of the Proximal Tibia: A Case Report and Review of the Literature

A rare case is reported of bilateral physeal lesions of the proximal tibia classified as Salter-Harris type II, which occurred simultaneously after a “flexion type” injury in a 14-year-old boy. Treatment was conservative on the nondisplaced side and surgical, by closed reduction and internal fixation, on the displaced side. There was no previous diagnosis of Osgood-Schlatter disease. After reviewing all the cases described previously, which occurred either consecutively or simultaneously, we conclude that less resistance of the growth plate, typical of late adolescence, likely represents the cause of this type of lesion

Quasi-stationary trajectories of the HMF model: a topological perspective

We employ a topological approach to investigate the nature of quasi-stationary states of the Mean Field XY Hamiltonian model that arise when the system is initially prepared in a fully magnetized configuration. By means of numerical simulations and analytical considerations, we show that, along the quasi-stationary trajectories, the system evolves in a manifold of critical points of the potential energy function. Although these critical points are maxima, the large number of directions with marginal stability may be responsible for the slow relaxation dynamics and the trapping of the system in such trajectories.Comment: 5 pages, 4 figure

Fertilizer type influences tomato yield and soil N2O emissions

Improvements in crop management for a more sustainable agriculture are fundamental to reduce environmental impacts of cropland and to mitigate effects on global climate change. In this study three fertilization types – ammonium nitrate (control); mineral fertilizer added with a nitrification inhibitor (3,4-dimethylpyrazole phosphate (DMPP)), and an organo-mineral fertilizer (OM) – were tested on a tomato crop in order to evaluate effects both on crop production and soil N2O emissions. Plants grown under OM fertilization had a greater relative growth rate compared to mineral fertilization, due to a higher net assimilation rate, which was related to a greater light interception rather than to a higher photosynthetic efficiency. OM fertilization determined the highest fruit production and lower soil N2O fluxes compared to NH4NO3, although the lowest soil N2O fluxes were found in response to mineral fertilizer added with a nitrification inhibitor. It can be concluded that organo-mineral fertilizer is a better nutrient source compared to mineral fertilizers able to improve crop yield and to mitigate soil N2O emission

AB0125 EXPRESSION OF INTERFERON TYPE I- AND TYPE II-INDUCED GENES IN PATIENTS WITH SJÖGREN'S SYNDROME WITH AND WITHOUT EXTRAGLANDULAR INVOLVEMENT

Background:It is well known that Sjögren's syndrome (SjS) is characterized by an upregulation of interferon (IFN)-induced genes. Namely, IFN type I signature has been reported in peripheral blood mononuclear cells (PBMCs) and in salivary glands of patients with this disease. However, few data are available on possible variability of IFN-induced gene upregulation in different clinical phenotypes of SjS.Objectives:To verify whether upregulation of IFN-induced genes is comparable in patients with SjS characterized by different clinical phenotypes, i.e., patients with systemic extraglandular manifestations (EGMs) versus patients with a disease limited to glandular features (GFs) and with widespread pain (WP).Methods:The study population was composed by 11 patients with SjS and EGMs (1 male, age range 18-78 years), and 10 patients with only GFs and WP (all females, age range 46-81 years), all classified according to ACR-EULAR criteria. The prevalence of anti-SSA(Ro) antibodies was 11/11 and 8/10, respectively. Lip biopsy was positive in all cases. Six healthy normal subjects were also included in the study as control population.Four IFN type I- and 5 IFN type II-induced genes were chosen for the study on the basis of previous literature data. Total RNA from each patient and control was isolated from purified PBMCs, followed by cDNA preparation and real time quantitative-PCR (RQ-PCR) analysis, using specific primer/probe sets. For calculation of relative expression, all samples were normalised against expression of a household gene (beta actin). A further normalization was performed against the mean value of relative expression obtained in the normal controls. Final fold change values were determined from the double-normalised values using the 2−ΔΔCT method (Applied Biosystems).Results:Fold change values of gene expression of both IFN type I- and type II-induced genes in PBMCs were different in the two clinical phenotypes of SjS. Fold change values of IFN type I-induced genes appeared strongly higher in patients with EGM, and some of them only moderately increased in those with only GF and WP. The expression of some of IFN type II-induced genes were slightly increased in patients belonging to both clinical phenotypes. Results are detailed in the table.Table.Fold change values of gene expression in patients with SjS plus EGMs, in patients with disease limited to GF and WP, and in controls.GeneMX1IFIT1IFT3IFI44IDO1GRP1MIGIP-10P2RY14SjS-EGMs85.938.524.440.425.18.34.51.55.5SJS-GF-WP4.21.72.04.84.11.20.60.31.3Controls2.11.61.11.51.41.31.51.31.4Legend. IFN type I-induced genes: MIX, IFN-induced GTP binding protein 1; IFIT1, IFN-induced protein with tetratricopeptide repeats 1; IFIT3, IFN-induced protein with tetratricopeptide repeats 3; IFI44, IFN-induced protein 44.IFN type II-induced genes: IDO1, indolamine-deoxygenase 1; GBP1, guanylate binding protein 1; MIG, C-X-C chemokine 9 (CXCL9); IP-10, C-X-C chemokine 10 (CXCL10); P2RY14, purinergic receptor 14.Conclusion:The present data indicate that IFN type I- and, to a lesser degree, type II-induced genes are upregulated in patients with SjS, but this phenomenon is consistently stronger in patients with systemic EGMs. In patients with only GFs IFN-induced gene upregulation is milder in PBMCs, and then probably more restricted to the exocrine target tissues.Disclosure of Interests:Nicoletta Del Papa: None declared, Claudio Vitali: None declared, Maurizio Lorini: None declared, Vincenzo Carbonelli: None declared, Wanda Maglione: None declared, Francesca Pignataro: None declared, Antonina Minniti: None declared, Nicola Montano: None declared, Roberto Caporali Consultant of: AbbVie; Gilead Sciences, Inc.; Lilly; Merck Sharp & Dohme; Celgene; Bristol-Myers Squibb; Pfizer; UCB, Speakers bureau: Abbvie; Bristol-Myers Squibb; Celgene; Lilly; Gilead Sciences, Inc; MSD; Pfizer; Roche; UC

EXAFS study of lead-free relaxor ferroelectric BaTi(1-x)Zr(x)O3 at the Zr K-edge

Extended X-ray absorption fine structure (EXAFS) experiments at the Zr K-edge were carried out on perovskite relaxor ferroelectrics BaTi(1-x)Zr(x)O3 (BTZ) (x = 0.25, 0.30, 0.35), and on BaZrO3 for comparison. Structural information up to 4.5 A around the Zr atoms is obtained, revealing that the local structure differs notably from the average Pm-3m cubic structure deduced from X-ray diffraction. In particular, our results show that the distance between Zr atoms and their first oxygen neighbors is independent of the Zr substitution rate x and equal to that measured in BaZrO3, while the X-ray cubic cell parameter increases linearly with x. Furthermore, we show that the Zr atoms tend to segregate in Zr-rich regions. We propose that the relaxor behavior in BTZ is linked to random elastic fields generated by this particular chemical arrangement, rather than to random electric fields as is the case in most relaxors.Comment: 13 pages, 12 figures, 4 tables. Submitted to Phys. Rev.