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To evaluate the incidence and clinical significance of pneumothorax (PTX) and pulmonary hemorrhage (PH) after CT-guided lung biopsy (CT-LB). To test correlations of PTX and chest tube insertion (CTI) with PH and other imaging and procedural parameters. Pre-procedural CT and CT-LB scans of 904 patients were examined. Incidence of PTX and PH and PH location (type-1 along needle track; type-2 perilesional) and severity according to its thickness (low grade 6 mm) were recorded. PTX was considered clinically significant if treated with CTI, PH if treated with endoscopic/endovascular procedure. Binary logistic regression analyses were used to determine the effects of different imaging and procedural parameters on the likelihood to develop PTX, CTI and PH and to define their correlation. PTX occurred in 306/904 cases (33.8%); CTI was required in 18/306 (5.9%). PH occurred in 296/904 cases (32.7%), and no case required treatment. Nodule-to-pleura distance (ORPTX = 1.052; ORCTI = 1.046; ORPH 1.077), emphysema (ORPTX = 1.287; ORPH = 0.573), procedure time (ORPTX = 1.019; ORCTI = 1.039; ORPH = 1.019), target size (ORPTX = 0.982; ORPH = 0.968) and needle gauge (ORPTX = 0.487; ORCTI = 4.311; ORPH = 2.070) showed statistically significant correlation to PTX, CTI and PH. Type-1 PH showed a protective effect against PTX and CTI (ORPTX = 0.503; ORCTI = 0.416). PTX and PH have similar incidence after CT-guided lung biopsy. PH along needle track may represent a protective factor against development of PTX and against PTX requiring CTI.

Simple Summary Patients with high-grade glioma (HGG) such as glioblastoma (GBM) who undergo surgical resection with adjuvant therapy have a mean overall survival of 14.6 months and 100% of recurrence. Thus, these disappointing outcomes in terms of glioblastoma life expectancy require seeking novel pharmacological tools, including drug repurposing. In the present study, we identify a novel molecular mechanism through which Losartan antagonizes Angiotensin II (Ang II)/Angiotensin II type I receptor (AGTR1) signaling, overexpressed in GBM cells. For instance, we demonstrate how Losartan drastically inhibits the stimulatory effects of Ang II on aromatase activity and consequently reduces local estrogen production, sustaining cancer progression. Thus, it is reasonable to repurpose Losartan as an adjuvant pharmacological tool to be implemented prospectively in the novel therapeutic strategies adopted in GBM patients. Abstract New avenues for glioblastoma therapy are required due to the limited mortality benefit of the current treatments. The renin-angiotensin system (RAS) exhibits local actions and works as a paracrine system in different tissues and tumors, including glioma. The glioblastoma cell lines U-87 MG and T98G overexpresses Angiotensin II (Ang II)/Angiotensin II type I receptor (AGTR1) signaling, which enhances in vitro and in vivo local estrogen production through a direct up-regulation of the aromatase gene promoters p I.f and p I.4. In addition, Ang II/AGTR1 signaling transactivates estrogen receptor-α in a ligand-independent manner through mitogen-activated protein kinase (MAPK) activation. The higher aromatase mRNA expression in patients with glioblastoma was associated with the worst survival prognostic, according to The Cancer Genome Atlas (TCGA). An intrinsic immunosuppressive glioblastoma tumor milieu has been previously documented. We demonstrate how Ang II treatment in glioblastoma cells increases programmed death-ligand 1 (PD-L1) expression reversed by combined exposure to Losartan (LOS) in vitro and in vivo. Our findings highlight how LOS, in addition, antagonizes the previously documented neoangiogenetic, profibrotic, and immunosuppressive effects of Ang II and drastically inhibits its stimulatory effects on local estrogen production, sustaining glioblastoma cell growth. Thus, Losartan may represent an adjuvant pharmacological tool to be repurposed prospectively for glioblastoma treatment.

Computed tomography-guided lung biopsy is a valid and safe procedure for characterizing pulmonary nodules. In the past years, this technique has been mainly used to confirm the malignant nature of undetermined pulmonary lesions; however, today its role has been completely renewed. With the advent of target therapy and immunotherapy, it has arisen for lung cancer, in inoperable patients, the necessity to obtain adequate bioptical material to perform a correct molecular characterization of the lesion. Moreover, the possibility of acquired drug-resistance mechanisms makes it necessary in some cases to rebiopsy these lesions over time. For these reasons, it is likely that the request of computed tomography-guided lung biopsy will increase in the future, therefore every radiologist should be confident with its most important aspects.

Rotator cuff calcific tendinopathy (RCCT) is a common and painful shoulder disease characterised by deposition of calcium into the rotator cuff’s tendond. Different therapeutic options have been proposed, but the ultrasound-guided percutaneous irrigation (US-PICT) is been proved as an effective and safe first-line treatment. It can be performed with a single- of a double-needle tecnique, using warm saline solution to improve the dissolution of the calcific deposit. The procedure is ended with an intrabursal injection of local anaesthetics and slow-release steroids to improve the pain relief and to prevent complications. US-PICT leads to significative improvement in the shoulder funtion and pain relief in the short and long term, with a low complications rate. (www.actabiomedica.it)

To retrospectively evaluate the mid-term outcomes of percutaneous radiofrequency ablation (RFA) with multitined expandable electrodes externally cooled with saline solution in patients with T1a renal cell carcinoma (RCC). In this retrospective study, we evaluated 39 RCC in 35 patients treated with CT-guided RFA in 41 procedures (2011–2017). All patients were staged T1a, N0, M0 prior to RFA. Mean tumor size was 24.48 mm. A 4-tined expandable RFA electrode cooled with pump-circulating saline was used. Efficacy was evaluated verifying complete tumor necrosis (no contrast enhancement on imaging) at the end of the procedure and on subsequent controls. Follow-up observation period was 5 years. Minor/major complications, hospitalization days, serum creatinine and GFR pre- and post-RFA (compared using paired t test) and post-operative pain (evaluated with NRS after treatment) were considered as safety indicators. Overall survival was also calculated (Kaplan–Meier method). Of 35 patients, 30/35 had 1 treatment (primary effectiveness rate 86%), 4/35 had 2 treatments and 1/35 had 3 treatments for residual disease. There were no relapses and no mid-long-term complications; 3 minor (8%) and 1 major (2.7%) complications during perioperative period were reported. Mean before and after RFA serum creatinine rates were, respectively, 1.08 mg/dl and 1.11 mg/dl (p value: 0.4117). NRS median value is 0.8. Hospitalization days median value is [2.8 ± 1.9] days. 91.4% of all patients survived, with a median overall survival time of 65 months. Mid-term results show that CT-guided RFA with multitined expandable electrodes externally cooled with saline solution is an effective and safe treatment in patients with RCC-staged T1aN0M0. Data reported in our study are in line with data reported in the literature from patients treated with other devices.

Percutaneous Needle Biopsy (PNB) is the insertion of a needle into a suspected lesion or an organ with the aim to obtain cells or tissue for diagnosis. It’s a relatively non-invasive procedure and is performed by radiologist under guidance of imaging techniques such as ultrasound (US), computed tomography (CT), fluoroscopy, magnetic resonance imaging (MRI), and positron emission tomography CT (PET-CT). The choice of imaging technique depends on the evaluation of the target lesion and patient compliance. PNB includes two categories: fine-needle aspiration biopsy (FNAB) that is the use of a thin needle (18-25 gauge) to extract cells for cytological evaluation; and core needle biopsy (CNB) that is the use of a larger needle (9-20 gauge) to extract a piece of tissue for histological evaluation. The indications for biopsy are the characterization of nature (benign or malignant) of a lesion, diagnosis and staging of tumor, and biological or immunohistochemical/genetic analisys on tissue. Success of PNB is the procurement of sufficient material to characterize lesions and to guide the patient outcome. Major complications are rare. PNB became a useful technique in diagnosis and study of retroperitoneal lesions, because of a more suitable access to specific intra-abdominal structures, lowering the risk of injury of interposed structures (such as bowel, great vessels). (www.actabiomedica.it)

Percutaneous renal artery embolization is a valid non-invasive technique alternative to nephrectomy for patients with symptomatic non-functioning allograft (graft intolerance syndrome—GIS). The purpose of this article is to report the experience of our centre. We analysed retrospectively 15 patients with symptomatic non-functioning renal allograft treated with percutaneous embolization from 2003 to 2017. Occlusion was obtained with the injection of calibrated microspheres of increasing size (from 100 to 900 μm) and completed with 5 to 8 mm metal coils placement in the renal artery. Technical success was achieved in all cases at the end of the procedure. Clinical success was obtained in 11 patients (73%). In four cases, nephrectomy was necessary: in one case because of septic fever and in three cases because of GIS persistence. In one case, it was possible to perform another procedure to embolize a perirenal collateral from a lumbar artery. Four patients (27%) reported minor complications which spontaneously resolved during the hospital stay. According to the scientific literature, we believe that, in selected patients, percutaneous renal artery embolization is a valid treatment option for GIS thanks to its efficacy, repeatability, minimal invasiveness and the absence of severe complications.

Detection of adrenal lesions, because of the widespread use of imaging and especially high-resolution imaging procedures, is increased. Because of the importance to characterize those findings, magnetic resonance imaging (MRI), in particular chemical shift imaging (CSI), is useful to distinguish whether a lesion is benignant or malignant and to avoid further diagnostic or surgical procedures. It represents the first choice of imaging in patient like children or pregnant women, and a valid complement to other imaging techniques like CT or PET/CT. In this review we analyze the role and characteristic of MRI and the imaging features of most common benignant (adenoma, hyperplasia, pheochromocytoma, hemorrhage, cyst, myelolipoma, teratoma, ganglioneuroma, cystic lymphangioma, hemangioma) and malignant [neuroblastoma, adrenocortical carcinoma (ACC), metastases, lymphoma] adrenal lesions.

The number of percutaneous radiofrequency ablation procedures performed for renal tumors is progressively increasing worldwide. Periodic imaging follow-up has the double role to guarantee the treatment efficacy over time and to early detect any possible complication. Tumor size reductions, as well as the appearance of the characteristic ‘halo sign’, are normal findings that represent good ablative outcomes. However the most reliable factor of ablation efficacy remains the total absence of contrast enhancing zones within the ablated area. The aim of this article is to illustrate the typical aspect of an effective radiofrequency ablation treatment, which are the imaging findings that may suggest the presence of residual tumoral tissue and which are the main early and late procedural complications.

Infants and children undergo imaging studies to evaluate a wide variety of congenital and acquired disorders. Imaging protocols have to consider the patient’s comfort, level of anxiety, and smaller size. The first imaging study is usually made with plain radiographs. The routine radiographic examination of the foot includes the anteroposterior (AP), lateral, and oblique projections. Magnetic Resonance Imaging (RMI) provides excellent anatomic detail of cartilage, vasculature and soft tissue thanks to superior soft tissue contrast and spatial resolution, so is valuable in many cases. According to the clinical and objective signs, guided by the radiographs images, we can be oriented to perform Computed Tomography (CT), CT imaging or MRI imaging. CT imaging is useful to observe the bones but it has the disadvantage of using radiation and doesn’t adequately define the bone’s non-ossified portions. On the contrary, MRI imaging is very useful in identifying the cartilaginous parts and vascular and soft tissues, thanks to its superior contrast and spatial resolution. Finally, it is important to orientate the diagnostic process keeping in mind the clinical sign of the patient and to use the most appropriate diagnostic technique. (www.actabiomedica.it)

This paper presents the results of a multidisciplinary study on two 14th century canvases attributed to Lorenzo Veneziano. In particular, two non-invasive spectroscopic techniques have been employed, imaging spectroscopy (IS) and X-ray Fluorescence (XRF). In order to perform the analysis in situ, the employed instruments were transportable. The purposes of this analytical approach were mainly to corroborate the authorship and to study the painting materials and execution technique of these two canvases. These two artworks are considered precious because they represent two evidences of the early use of the canvas support in this early period in the North of Italy. Since the paintings are in very delicate conditions, the principal objective of the investigations was to gather as much information as possible avoiding invasive analytical procedures. The paper discusses the potentialities and limitations of the integration of a mobile XRF spectrometer with a transportable IS device, developed to study large-sized surfaces. By means of the elemental composition given by XRF and the colourimetric data and reflectance spectra collected by IS, it has been possible to identify different materials (gypsum,azurite...) and to achieve a better understanding of the employed painting technique. The data confirm that the two canvases have been produced with painting materials and technique which are in good agreement with those of Lorenzo Veneziano. The obtained results illustrate the suitability of the integration of XRF with IS to solve similar analytical issues when sampling is not possible. (C) 2013 Elsevier Masson SAS. All rights reserved.

In this work we report a pre-restoration spectroscopic study by a multi-technique approach on the green pigment and the binder used in illuminations in a codex of the late 15th century. Our analysis aimed to characterize the badly deteriorated parts of the codex, mainly the green parts, by electron paramagnetic resonance (EPR), X-ray diffraction (XRD), X-ray fluorescence (XRF) and infrared spectroscopy (ATR-IR). We will show that a combined study by EPR and IR spectroscopies on model systems allowed us to refine the general information obtained with the other techniques and to identify the binding media surrounding the chromophore Cu(II) ion.

Background and methods Portal vein thrombosis (PVT) has been reported as a complication of IBD in some case reports. We describe the presentation, diagnostic approaches, underlying risks factors and clinical outcome of 8 IBD patients with PVT. Case-series The patients presented with partial PVT (4 patients) or portal cavernoma. Five patients had undergone surgery. In 2 patients portal biliopathy was diagnosed after detection of PVT. In 4 patients, the diagnosis of PVT was made while IBD was in remission. Five patients showed at least one risk factor for hypercoagulability: lupus anti-coagulant (one patient), increased von Willebrand factor (2 patients) or homocysteine levels (4 patients). Four patients received anticoagulant therapy for 6 months. None experienced other thrombotic events during a median of 5 years (range 2–8 years). Conclusion PVT is a potential complication of IBD, usually associated with acquired or inherited risks factors for hypercoagulability and with a benign outcome.

Some tesserae of San Marco Basilica (Venice) have been investigated in order to understand the possibilities of non-destructive investigation in the study of glass mosaics. In particular, the tesserae belonging to a mosaic piece coming from the Baptistery (dated about 1340) have been previously investigated by optical microscopy (table and portable) and divided in groups according with their optical appearance. Then the results have been compared with PIGE-PIXE, p-XRF, XPS data and elaborated by PCA. The results show that green tesserae and the “cartellina” (both characterised by low cromophore amounts) can be difficultly studied by portable instruments. On the other side, the red tesserae, although similar from the optical point of view, do not always show the same composition.

Post-depositional processes in pottery can give rise to chemical and mineralogical alterations, the extent of which is closely related not only to the microstructure and composition of the potsherds, but also to the chemical–physical conditions of the burial environment. The present paper describes the characterization of post-depositional alterations and identification of processes involving pottery buried in lagoon-like environments. A set of various types of Roman transport amphorae and African Red Slip ware (ARS), collected from two archaeological sites characterized by a lagoon-like depositional environment and showing evident changes in the original colours, was analysed by a combination of microstructural, mineralogical and microchemical approaches. The formation of pyrite after hematite, jarosite after pyrite and microstructural substitution features are interpreted here in terms of the chemico-physical conditions of the burial environment and their evolution in time.

This study evaluates the role of Ca and P precursors and of two different preparation methods, ceramic and hydrothermal, in the synthesis of undoped- and Fe3+-doped hydroxyapatite (HA), and tests the Fe3+ solubility limits in HA. Previous studies have noted that different synthesis conditions lead to different products in variable amounts and recent literature quotes the highest amount of Fe3+ substituting for Ca in the HA structure in the range 0.2–0.5 as a function of temperature. Samples were characterized by X-ray powder diffraction, Mossbauer and Infrared spectroscopies. The samples obtained by the ceramic method at 800 °C contain mixtures of B-type carbonate-apatite and other phosphates whose type and number depend on Ca and P precursors. Samples synthesized at higher temperatures contain mixtures of hydroxyapatite, tricalcium phosphate and of magnetic phases, as haematite and ferrite, whose relative amounts depend on nominal composition and thermal treatment. Samples obtained by a hydrothermal route are richer in HA phase with respect to the solid state one, even if the obtained HA percentage depends on the pH. Mossbauer results suggest that Fe3+ is randomly distributed between Ca1 and Ca2 sites. At the highest doping levels a reduction takes place with the formation of iron(II) and magnetite.

International audience; Six sulphato derivatives and adducts containing SnPh3 or SnR2Cl (R=Bu, Ph) groups have been synthesized and studied by infrared and Mössbauer techniques. The suggested structures are infinite chains or oligomers, the sulphate behaving as a mono- bi-, tridentate, mono- or bichelating ligand.

A series of iron(III) hydrated oxide/oxyhydroxide/oxide was prepared by precipitation from Fe(III) aqueous solutions, to obtain supports suitable as Au(0)-based catalysts. During synthesis, all parameters – pH, temperature and adding rate – were strictly controlled in order to achieve highly reproducible synthesis. The method of purification was also planned in order to remove nitrate ions that can influence the catalytic activity and/or the support properties, without modifying the structure or particle dimension of the support. Dialysis was identified as the best method for purifying the hydrated oxide/hydroxide, i.e., ferrihydrite and goethite; while ammonium carbonate washing proved to be the most successful for the other hydroxide/oxides. Mossbauer spectroscopy and X-ray powder diffraction pointed out the complexity of all these systems, proving the extreme importance of synthesis temperature for crystallinity, particle dimension, and amount of hydroxide/oxide.

The P - V and T - V equations of state of a natural biotite sample (Mg/Fe ratio ≈ 1) have been studied using in-situ high-pressure (0.0001–11 GPa) synchrotron radiation powder diffraction at the European Synchrotron Radiation Facilities (ESRF) in Grenoble, France, and in-situ high-temperature (298–610 K) laboratory X-ray powder diffraction. A third-order Birch-Murnaghan model [ V = 498.7(1) A3, measured value] provides the following elastic parameters: K = 49(1) GPa, K ’ = 8.1(5). The volume thermal expansion is satisfactorily described by a constant value resulting in 37(2) 10−6 K−1. Mossbauer spectroscopy proves that REDOX reactions have occurred upon heating, presumably 2(OH− + Fe2+) → 2O2− + 2Fe3+ + H2↑ and/or 4Fe2+ + 2OH− + O2 → 4Fe3+ + 3O2− + H2O. On the basis of the elastic and thermal parameters measured we have modeled the deformation contribution ( G deform) to the Gibbs energy. The third-order Birch-Murnaghan model with V fixed at its experimental value and the model with refined V do not significantly differ from one another in terms of G deform. A comparison based on G deform between biotite and phlogopite shows a better compliance to P of the former, though balanced in mineral reactions by a difference of molar volume, i.e., V (biotite) > V (phlogopite).

The reaction of dimethyl-, diethyl- and dibutyltin(IV) oxide with 2,6-lutidine-α2,3-diol (Lu) [2-(hydroxymethyl)-3-hydroxy-6-methylpyridine] in toluene/ethanol has been investigated. The compounds were isolated and characterized by IR, Raman and Mossbauer spectroscopy, EI and FAB mass spectrometry and 1H and 119Sn NMR spectroscopy. The structures of Lu and [SnMe2(H2O)(Lu-2H)] were determined by X-ray diffraction. The crystal of [SnMe2(H2O)(Lu-2H)] contains dimeric [SnMe2(H2O)(Lu-2H)]2 units, in which the tin atom is coordinated to the O atoms of the two deprotonated hydroxymethyl groups and one deprotonated phenolic hydroxyl group. The distorted octahedral coordination polyhedron of each tin atom is completed by a water molecule and two methyl C atoms. The butyl derivative exhibited significant in vitro antitumor activity against the human carcinoma cell lines HeLa-229, A2780 and A2780cis, although minor than that of the pyridoxine derivative prepared previously. © 2007 Elsevier B.V. All rights reserved.

Resume Des composes organostanniques contenant SnCl 4 , SnCl 5 − et SnCl 6 2− ont ete synthetises et etudies par spectroscopies infrarouge, Raman et Mossbauer. L'environnement autour de l'etain est octaedrique dans tous les complexes. Les spectroscopies infrarouge et Mossbauer ont ete utilisees pour montrer que l'ion thiocyanate est N-donneur. La structure moleculaire de [C 6 H 5 COCH 2 NH 3 ] 2 [SnCl 6 ] a aussi ete determinee par diffraction des rayons X ; elle consiste en des ions SnCl 6 2− octaedriques relies par des liaisons hydrogene entre les atomes de chlore et les atomes d'hydrogene du groupement NH 3 + des cations C 6 H 5 COCH 2 NH 3 + .

Molecular structures of [(Ph 3 Sn) 2 O 3 Se] ( 1 ) and [(Ph 3 Sn) 2 O 4 Cr](CH 3 OH) ( 2 ) have been determined using spectroscopic techniques and X-ray analysis. Each structure consists of polymers containing two types of tin centres: one of them is bridged by two oxygen atoms of the trifunctional oxyanion into a helical chain while the other is pendant to this chain. In the case of the chromato derivative the pendant tin is also bonded to the oxygen atom of the solvent (methanol); hydrogen bonds between the methanol and the non-coordinated oxygen of the chromate generate a three-dimensional structure containing tin atoms in a trigonal bipyramidal environment. In contrast, the two tin centres in the non-solvated selenito derivative have distinct geometries (tetrahedral and trigonal bipyramidal). Variable temperature Mossbauer spectroscopy data are consistent with the polymeric structure of the selenito derivative while NMR spectroscopy shows the presence of monomeric species in solution.

The reaction between the ligands 4-(trifluoromethyl)pyrimidine-2-thione (4-CF3pymSH) and 6-methyl-4-(trifluoromethyl)pyrimidine-2-thione (6-Me-4-CF3pymSH) and the corresponding diorganotin(IV) dichloride [R2SnCl2] (R = Me, tBu or Ph) or diphenyllead(IV) dichloride in the presence of triethylamine yields the diorganotin(IV) complexes [R2Sn(4-CF3pymS)2] and [R2Sn(6-Me-4-CF3pymS)2] or diorganolead(IV) complexes [Ph2Pb(4-CF3pymS)2] and [Ph2Pb(6-Me-4-CF3pymS)2], respectively. The compounds have been characterised by microanalysis, mass spectrometry and by IR and Mossbauer spectroscopy and, in the case of the compound that was sufficiently soluble, by 1H, 13C, 119Sn and 207Pb NMR spectroscopy. The compounds [Me2Sn(4-CF3pymS)2] (1), [Ph2Sn(4-CF3pymS)2] (2), [Ph2Sn(6-Me-4-CF3pymS)2] (5), [tBu2Sn(6-Me-4-CF3pymS)2] (6), [Ph2Pb(4-CF3pymS)2] (7) and [Ph2Pb(6-Me-4-CF3pymS)2] (8) have also been characterised by X-ray diffraction. The X-ray crystal structures show that the metal centre in all these complexes is in a distorted octahedral environment with bonds to two carbon atoms from the aryl or alkyl substituents and to sulfur and heterocyclic nitrogen atoms from the pyrimidine derivative, which acts a (κ2-N,S) chelating ligand. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

Here we describe the evolution of iron-bearing phases in the firing of carbonate-rich illite and chlorite clay. Breakdown of chlorite forms an amorphous phase, which continues to retain iron in a (distorted) paramagnetic octahedral site, until carbonates start to decompose and react at 750 °C, forming Ca-silicates. Only at this temperature can hematite nucleate and grow in specific micro-domains located in former chlorite flakes. At 950 °C, decomposition of illite in the presence of an amorphous phase and CaO produces a melt in which nano-sized hematite may nucleate, although its growth is inhibited due to low diffusion with respect to soaking time.

Ti0.030 Sc0.002V0.008Ga0.001Ni0.010Zn0.015)(Si2.970Al0.022P0.008)O11.991F0.009 (OH) with La > Ce and relevant quantities of Th and Cr. Thus, this mineral may be defi ned as chromian, thorian, cerian dissakisite- (La). Dissakisite is a rare mineral. Rouse and Peacor (1993) refi ned dissakisite-(Ce) with composition Ca1.05(Ce0.57La0.33Nd0.07 Pr0.03)Σ1.00Mg0.93Fe0.14Ti0.06Al1.91Si2.94O12((OH)0.94F0.06), while Yang and Enami (2003) described a dissakisite close to our sample in ABSTRACT The crystal chemistry of the new mineral dissakisite-(La), the Mg-analogue of allanite-(La) with ideal formula CaLaAl2MgSi3O12(OH), was studied by single-crystal X-ray diffraction and Mossbauer spectroscopy. Diffraction data indicated that it has a partially metamict state with expanded cell pa- rameters a = 8.959, b = 5.7226, and c = 10.232 A, β = 115.19°, and V = 474.7 A 3 . The crystal structure was refi ned to R(I/σ(I) > 4) of 3.45% and wR2 of 8.52% (S.G. P21/m). The displacement parameters are unusually large as consistent with positional disorder. Ca and REE are partitioned between the A1 and the A2 sites, Fe 2+ between the M3 and the A1 sites, and Fe 3+ between the M3 and the M2 sites. Th is confi ned to A1. The Mossbauer spectrum implies the presence of fi ve different iron sites, three of which are attributed to Fe 2+ at the M3 site, one to Fe 2+ at the A1 site, and one to Fe 3+ at a rather distorted octahedral site. Annealing at 700 °C caused contraction of cell edges (b and c shrank by 0.5%, a by 0.3%, β only slightly decreased; ∼1% in V) and of bond distances, with a consequent overall increase in bond valences. Displacement parameters decreased by about 30%, leading to a signifi cant increase from 1495 to 1627 in the number of refl ections with I/σ(I) > 4. Structure rearrangement was achieved by means of fl exible points such as the two-coordinated oxygen atoms O8 and O9, and by greater volume decreases in M3, A1, A2, and Si3 polyhedra. Si tetrahedra behaved non-rigidly, at variance with what was observed for isomorphous substitution and thermal expansion. Despite the high Th content and the age of the mineral, the crystal structure is well preserved. The above paradox could be explained by a thermal event after formation of the mineral that reversed previous damage, or by a prolonged period under relatively high-temperature conditions. Keywords: Crystal structure, dissakisite-(La), Mossbauer spectroscopy, new minerals, high-tem- perature studies

Tin dioxide and ruthenium(platinum)-doped tin dioxide were synthesized in the form of inverted opals, aiming to investigate the interaction of these materials with CO reducing gas. The results of electron paramagnetic resonance (EPR) investigation allowed us to conclude that CO interaction causes the formation of singly ionized oxygen vacancies located in the subsurface region. These ones transfer their electrons to transition metal centers, Ru or Pt, enhancing the SnO2 surface reactivity toward CO. The reduction of Ru4+ and Pt4+ was assessed both by EPR and Mössbauer spectroscopy. Resistance measurements showed that the materials are well-suitable for use in CO sensor devices because of their reproducible and fast electrical response; this was related to the homogeneous and high dispersion of Ru and Pt centers in the oxide matrix and to the subsurface location of the species active in the electron-transfer processes. © 2005 American Chemical Society.

Optical, SEM-EDS and TEM microscopy, Mossbauer and UV–Vis spectroscopy, SIMS spectrometry and ICP spectroscopy, were carried out on sixty vitreous finds, with particular attention to the trace elements, in order to correlate them to the raw materials, the working instruments and the technology employed. The colours of these vitreous finds have been studied in detail to establish the presence and kind of chromophores, the redox conditions used for obtaining of the vitreous mass during the fusion process, the role of the oxidation state and chemical environment of the different metal ions, etc. Eight crucibles and one refractory material were also investigated by XRD diffractometry and TG-DTA thermogravimetry. Their composition, morphology and thermal behaviour gave information on the working temperature inside the kilns. These studies offer a scientific contribution to the archaeological requests to characterise correctly the pre-industrial glass manufactures in Valdelsa. The obtained results allow us to gain a more exhaustive knowledge of the production technology at Germagnana (14th century) and Gambassi (16th century) and of the provenance of the employed raw materials and to register differences and analogies in their production process.

The Fe 3+ /Fetot of all Fe-bearing minerals has been analysed by Mossbauer spectroscopy in a suite of biotite-rich to biotite-free graphitic metapelite xenoliths, proxies of an amphibolite-granulite transition through progressive biotite melting. Biotite contains 9 to 16% Fe 3+ /Fetot, whereas garnet, cordierite and ilmenite are virtually Fe 3+ -free (0-1% Fe 3+ /Fetot) in all samples, regardless of biotite presence. Under relatively reducing conditions (graphite-bearing assemblages), biotite is the only carrier of Fe 3+ during high-temperature metamor- phism; therefore, its disappearance by melting represents an important event of iron reduction during granulite formation, because haplogranitic melts usually incorpo- rate small amounts of ferric iron. Iron reduction is accompanied by the oxidation of carbon and the production of CO2, according to the redox reaction: 2Fe2O ðBtÞ 3 þ C ðGrÞ ) 4FeO ðCrd;Grt;Ilm;OpxÞ þ CO ðfluid;melt;CrdÞ 2 : Depending on the nature of the peritectic Fe-Mg mineral produced (garnet, cordierite, orthopyroxene), the CO2 can either be present as a free fluid component, or be completely stored within melt and cordierite. The oxi- dation of graphite by iron reduction can account for the in situ generation of CO2, implying a consequential ra- ther than causal role of CO2 in some granulites and migmatites. This genetic model is relevant to graphitic rocks more generally and may explain why CO2 is present in some granulites although it is not required for their formation.

Effects of electronic charge disproportionation were observed by 57Fe Mossbauer spectroscopy at low temperatures in substituted LaFeO3 perovskites as (La1−xCax)FeO3 and La(Fe1−xMgx)O3 (x≤0.5). The presence of both Fe3+ and Fe5+ species was evidenced in both series of compounds. Direct evidence for disproportionation was supported by correlating the Mossbauer results with the chemical determination of tetravalent iron at RT. The evolution of hyperfine parameters vs. substitution degree was comparatively analysed for Fe3+ and Fe5+ ions in relation to their electronic microscopic origin. Electron delocalisation processes are discussed in terms of ion distribution and valence state.

A carboxylic gel-type resin, poly-4-vinylpyridine-methacrylic acid-N, N'-methylenebisacrylamide is designed and synthesized in order to be able to incorporate both FeIII and, potentially, also AuIII in its polymer framework. Along with the gradual substitution of H+ with Na+, of Na+ with Fe3+/3 and after a very controlled and gradual precipitation of FeIII as oxihydroxides induced by the hydrolysis of urea directly inside the nanoporous domains of the metalated resin particles, an organic-inorganic composite is obtained. The material is characterized with TGA, ESEM, XRMA and Mossbauer spectroscopy.

A set of nine samples of axinite, selected from 60 specimens from worldwide localities, were investigated by single-crystal X-ray diffraction, electron and ion microprobe, and 57 Fe Mossbauer spectroscopy. The selected samples cover the compositional join from almost pure ferroaxinite (80%) to pure manganaxinite (95%). A new crystal-chemical formula for the axinite mineral group is proposed: VI [X1 X2 Y Z1 Z2] 2 IV [T1 T2 T3 T4 T5] 2 O 30 (O w OH 1− w ) 2 , where VI and IV are coordination numbers; X1 = Ca and very minor Na; X2 = Ca (in axinites) or Mn (in tinzenite); Y = Mn (in manganaxinite and tinzenite), Fe 2+ (in ferroaxinite) or Mg (in magnesioaxinite), with minor Al and Fe 3+ ; Z1 = Al and Fe 3+ ; Z2 = Al; T1, T2, and T3 = Si; T4 = Si (and presumably very minor B); T5 = B and minor Si. Charge unbalance ( w ), due to heterovalent substitutions, is compensated for by O 2− → OH − substitution. From ferroaxinite to manganaxinite, cell volume increases linearly from 568.70 to 573.60 A 3 . This is mainly due to an increase in the mean distance from 2.220 to 2.255 A, which is directly related to the Mn population (up to 1.89 apfu). Fe 3+ concentrations, as determined by 57 Fe Mossbauer spectra at 80 K, sub-regularly increase up to 0.27 apfu, and three cases are evidenced: (1) Fe 3+ 2+ (or no Fe 3+ ), in ferroaxinite; (2) Fe 3+ 2+ , in intermediate compositions, and (3) Fe 3+ > Fe 2+ (or only Fe 3+ ), in manganaxinite. Chemical and structural data were co-processed via a computer minimization program to obtain the cation distribution scheme. Adopting the Hard-Sphere Model, empirical cation-oxygen distances were refined for every cation in the axinite structure. The results revealed that Fe 2+ is ordered at the octahedral Y site (up to 1.61 apfu), whereas Fe 3+ is ordered at the octahedral Z1 site (up to 0.26 apfu) and is almost absent in the smallest Z2 site, which is fully populated by Al. The observed Fe 3+ partitioning is in agreement with the structural results, which show that the Z1 octahedron is always larger than Z2. Moreover, no Fe 3+ is found at the tetrahedral sites, but Si → B substitution occurs at T5. The continuous Y dimensional increase from ferroaxinite to manganaxinite involves progressive enlargement of the edge-sharing Z1 octahedron. As a consequence, the Z1 Fe 3+ → Z1 Al 3+ substitution is structurally favored toward manganaxinite and points to a new end-member with the suggested name “ferri-manganaxinite.”

The sandwich (black core) structure in the production of Etruscan-Padan type pottery was investigated. Petrographic, X-ray diffraction (XRD) and Mossbauer data showed that colour changes from core to margin are related to differences in both Fe oxidation state and abundance of maghemite, hercynite and hematite. The occurrence of maghemite and hercynite and the higher quantity of Fe(II) in the cores suggest poor oxygen diffusion in the potsherds during firing. This is congruent with the occurrence of high fractions of paramagnetic Fe in octahedral sites, located in the amorphous phase probably derived from chlorite breakdown, and with the wide range of grain-size distribution of oxidic particles, indicated by the slowing down of superparamagnetic relaxation as temperatures are lowered.

A large variety of pictorial models capable of simulating the ancient polychromes of wall paintings and paintings on mobile supports has been prepared and aged by appropriate procedures under different climatic conditions, such as exposure to UV radiation or chemical pollutants (i.e. NO x , SO x ). A comparison of the physicochemical properties of these models, particularly concerning their material components, with those resulting from the ageing procedures revealed significant differences that can be used as possible “decay markers”. Micro-FT-IR, NIR, UV–vis, SEM-EDS, XRD and, where possible, Mossbauer spectroscopy have been used in order to identify surface and/or bulk variations in the physicochemical properties of the samples prepared. Decay markers have been found for aged models containing linseed oil, copper resinate, lead white and zinc white. Moreover, interactions between organic and inorganic components have been revealed. The data obtained have been evaluated also by comparison with the results obtained by other techniques, albeit complementary, (i.e. GC–MS, XPS) on the same pictorial models, within an inter- and multi-disciplinary collaboration.

The reactions of dimethyl-, diethyl- and dibutyltin(IV) oxides with pyridoxine (PN) in toluene/ethanol led to the formation of compounds [SnR2(PN-2H)] which were characterized by EI and FAB mass spectrometry and by IR, Raman, Mossbauer and 1H, 13C and 119Sn NMR spectroscopy. The structures of [SnEt2 (PN-2H)]· CH3OH, [SnBu2(PN-2H)] and [SnEt2(PN-2H)(DMSO)] were determined by X-ray diffractometry. The first two contain dimeric [SnR2(PN-2H)]2 units in which two bridging-chelating pyridoxinate anions link the Sn atoms, while in [SnEt2(PN-2H)(DMSO)] the DMSO coordinates to the tin atom via its O atom in a similar dimeric unit. © 2003 Elsevier B.V. All rights reserved.

For comparison with the corresponding pyridoxine complexes we have prepared dimethyl-, diethyl-, dibutyl- and diphenyltin(IV) complexes of N-methylpyridoxine (MePN). The compounds [SnMe2(MePN−H)]I (1), [SnEt2(MePN−H)]I (2), [SnBu2(MePN−H)]I (3) and [SnPh2(MePN−H)]I·H2O (4) were isolated and characterized by IR, Raman, Mossbauer, 1H, 13C and 119Sn NMR spectroscopy, and by EI and FAB mass spectrometry. The crystal structures of [HMePN]I and of compounds 1, 2·2H2O and 3 were determined by X-ray diffractometry. Their lattices contain dimeric [SnR2(MePN−H)]22+ units (R = Me, Et, Bu) in which two bridging-chelating methylpyridoxinato anions link pentacoordinate Sn atoms with coordination polyhedra closer to square pyramids than to trigonal bipyramids. NMR results show that the dimeric cations persist in (CD3)2SO. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

Titanium-rich biotites from graphite-bearing metapelitic xenoliths, equilibrated at ca. 850 °C and 7 kbar in the presence of a granitic melt, have been studied through complete chemical analysis and single-crystal XRD refinements. The chemical study combines EMP analyses, hydrogen determination by both SIMS and C-H-N elemental analysis, and Mossbauer spectroscopy. Biotites in the analyzed xenoliths have TiO 2 contents ranging from 4.5 to 4.9 wt% and an X F e of 0.67. Their F and Cl contents are negligible, and Fe 3 + /Fe t o t ranges from 10 to 16%. The H 2 O content of the biotites ranges from 2.4 to 2.8 wt%, and a small fraction of H is accommodated in the lattice as NH 4 . Based on these full chemical analyses, the calculated OH occupancy is 1.26 to 1.30 groups per formula unit, more than one third less than the stoichiometric value. The entrance of Ti in the octahedral site of biotite is consistent with the Ti-oxy exchange, whereas Ti-Tschermak or Ti-vacancy substitutions play a very minor role. The Fe 3 + -oxy exchange cannot account for the observed OH deficiency. From single-crystal XRD, biotites belong to the 1M polytype and contain variable amounts of stacking faults. The c cell parameter, K-04 and o u t e r distances provide an independent estimate of the OH content, which agrees with SIMS determinations. The linear relationship between V I Ti 4 + and the bond-length distortion of the cis-M2 octahedron reveals the partitioning of Ti 4 + in M2, and the Ti 4 + off-center shift toward 04 supports the occurrence of the Ti-oxy exchange. The ordering of Ti 4 + over two non-equivalent M2 sites, which would be favored energetically, is in agreement with the evidence for a third octahedral site suggested by Mossbauer spectroscopy. The biotite dehydrogenation combined with the partitioning of Ti 4 + in M2 and the low thermal expansion of Ti 4 + -containing octahedra, are the keys to understanding the thermal stabilization of Ti substitution in biotites.

The results on deprotonation and cation partitioning as a function of temperature in the tetrahedral and octahedral sites of a phengite 3 T , (K 0.94 Na 0.02 ) ∑0.96 (Al 1.43 Mg 0.33 Fe 0.25 ) ∑2.01 (Si 3.47 Al 0.53 ) ∑4 O 10 (OH) 2 , from Cima Pal (western Alps) are presented and discussed. They have been obtained by a synergic approach based on neutron powder diffraction from 293 K to 873 K, and on Mossbauer spectroscopy at ambient conditions, of the sample before and after heating. Order is observed at room temperature in both tetrahedral (Si fully occupies T 1) and octahedral (Al almost fills M 2) sites. Upon heating, deprotonation [mainly according to the reaction 2[(OH) - + Fe 2+ ] → 2O 2- + 2Fe 3+ + H 2 ↑], Fe oxidation and inter-site cation re-ordering reactions take place. Al moves by ~ 0.1 atoms from M 2 to M 3, and is replaced by Mg and Fe; Fe 2+ and Fe 3+ occupy different M -sites, after cooling, whereas Fe 2+ was partitioned on two sites, one site shared with Fe 3+ , before heating.

Samples of γ-Fe2O3 nano-particles with a mean size of 4.0(3) nm and with different hydration and surfactant degrees were prepared by sol–gel methods. Morphology and structural data were obtained by transmission electron microscopy and x-ray diffraction, whereas the surface effects and hyperfine interactions were analysed mainly by Mossbauer spectroscopy. The relative number of surface iron positions was found to be proportional to the amount of OH− and SO42− groups on the particle surface, which in turn is strictly dependent on the preparation conditions. Strong relaxation processes versus temperature were evidenced in the analysed systems. New criteria for the evaluation of the blocking temperature via Mossbauer measurements are proposed. The results are in good agreement with blocking temperatures obtained by magnetic measurements. Moreover, it was shown that the inter-particle magnetic interactions decrease with the number of iron surface states.

Pyridoxal 5′-phosphate (PLP) and pyridoxal (PL) itself were reacted with diorganotin(IV) derivatives in the presence and absence of aminoacids. With PLP the complexes [SnR 2 (PLP-2H)] (R=Me, Et, Bu) were isolated and characterized by EI and FAB mass spectrometry and by IR, Raman and Mossbauer spectroscopy. Reaction mixtures containing PL, valine or glycine and SnR 2 (OAc) 2 (R=Me, Et) afforded complexes of the form [SnR 2 (PLPM-2H)], where PLPM is the Schiff base formed by condensation of PL and pyridoxamine (PM). PM was presumably formed by transamination between valine or glycine and PL. The PLPM complexes, and their butyl and phenyl analogues, were also synthesized directly by reacting SnR 2 O and PLPM, and were characterized by EI and FAB MS, by IR, Raman, Mossbauer and NMR spectroscopy, and in the case of the methyl and ethyl compounds by single-crystal X-ray diffractometry. Crystals of [SnMe 2 (PLPM-2H)]·H 2 O and [SnEt 2 (PLPM-2H)] consist of molecules in which the ligand is bound to the metal through the O atoms of the two deprotonated phenolic hydroxyl groups and the iminic N atom, and the metal exhibits distorted square pyramidal coordination. Both PLPM and its complexes show intense antibacterial activity against Pseudomonas aeruginosa (ATCC27853), but only the complexes exhibit significant activity against the other four bacterial strains assayed, Staphylococcus aureus , Bacillus subtilis , Escherichia coli and a carbapenem-resistant P. aeruginosa strain.

The synthesis and characterization of new coordination compounds of some organotin(IV) chlorides with ethylsarcosine hydrochloride (N-methylglycine ethyl ester hydrochloride) is reported; the ligand molecules appear to be bound to the tin atoms through the carbonyl oxygen atoms by means of dative bonds. As single crystals were not obtained, a number of experimental techniques were used to accomplish a definitive characterization and determination of their structure. The results obtained by 1H, 13C, 119Sn NMR, FT-IR and 119mSn Mossbauer spectroscopy and thermogravimetric analysis suggested pentacoordination for the 1:1 (Sn:ligand (ESH)) derivatives, [R2SnCl2(ESH)]+Cl−, in a trigonal bipyramidal (TBP) structure, and hexacoordination for the 1:2 complexes, [R2SnCl2(ESH)2]2+2Cl−, in an octahedral structure (R = Me, n-Bu, Ph; ESH = protonated ethylsarcosine, CH3CH2O(O)CCH2N(CH3)H2+). The triphenyltin(IV) chloride ethylsarcosine hydrochloride derivative exists only as a 1:1 pentacoordinated adduct in a strongly distorted TBP structure. Finally, the compounds have been tested for in vitro cytotoxic activity against human adenocarcinoma HeLa cells, showing, in some cases, a high potency, even at low concentration. Copyright © 2002 John Wiley & Sons, Ltd.

The reaction of μ-nitrido[((tetraphenylporphyrinato)manganese)(phthalocyaninatoiron)], [(TPP)Mn−N−FePc], with I2 in THF develops with the formation of two different species, i.e., [(THF)(TPP)Mn−N−FePc(H2O)](I5)·2THF (I) and [(TPP)MnIV−N−FeIIIPc](I3) (II). On the basis of single-crystal X-ray work and Mossbauer, EPR, Raman, and magnetic susceptibility data, I, found to be isostructural with the corresponding Fe−Fe complex, is shown to contain a low-spin triatomic MnIVNFeIV system (metal-centered oxidation). Data at hand for II (Mossbauer, EPR, Raman) show, instead, that oxidation takes place at one of the two macrocycles, very likely TPP (ligand-centered oxidation). The same cationic fragment present in I, and containing the MnIVNFeIV bond system, is also obtained when (TPP)Mn−N−FePc is allowed to react in THF with (phen)SbCl6 (molar ratio 1:1). There are indications that the use of (phen)SbCl6 in excess (2:1 molar ratio), in benzene, probably determines further oxidation with the formation of a species sh...

Glasses of the nominal compositions.xNb2TO5-(1 - x) (95mol% NaPO3-5% Na2B4O7) (x = 0, 10.3, 20.6, 30.0, 36.5 or 43.0) and x-Ta2O5-(1 - x) (95mol% NaP03-5mol%Na2B4O7) (x = 0, 5.0, 9.3 or 14.0) were prepared by conventional quenching of the melts. Raman spectroscopy shows that introduction of T2O5 (T = Ta or Nb) in smali amounts gives rise to the formation of ‘isolated’ TO6 octahedra. As the concentration of T2O5 increases, the spectra suggest the formation of corner-sharing TO6, octahedra and finally, for the glasses richest in T2O5, of a three-dimensional association of cornersharing, less distorted octahedra. All these considerations lead to the conclusions that both niobium and tantalum in octahedral coordination act as network formers strengthening the glass network. The near-infrared spectra have provided information on the coordination geometries of iron(II) that has been used for the interpretation of the Mossbauer spectra. In this way the simultaneous presence of iron(III) and iron(II) in ...

The reactions of bis[triphenyltin(IV)] selenate monohydrate [(Ph3Sn)2O4Se · H2O ] with tetraphenylphosphonium halides Ph4PX (X = Cl, Br) led to the formation of 1:1 complexes of formula {Ph4P[(SeO4)(SnPh3 (SnPh3X)]k [X = Br (I) or Cl (II)], which were characterized by infrared, Mössbauer and H, 13C and Sn 119Sn NMR techniques and by X-ray diffractometry. The complexes have polymeric structures in which the [SnPh3]+ units alternate with bridging [SeO4]2- units, each of which also bears an SnPh3X side chain. In both the [SnPh3]+ and the [SnPh3X] units the coordination polyhedron of the tin atom is a distorted trigonal bipyramid.