SLab Data Manager

The SLab Data Manager is a tool developed for helping activities in IAPS SLab structure. The app has the main goal of allowing researchers in processing and saving spectra saved during the acquisition sessions. Several kinds of processing tools have been made available to create a flexible and useful tool. In this user manual it will be explained how to use the application for acquiring spectra, for processing them and saving raw and processed spectra into the SLab database (DB in the following)

Compartmental tongue surgery for intermediate-advanced squamous cell carcinoma: A multicentric study

Background: A multicentric study was conducted on technical reproducibility of compartmental tongue surgery (CTS) in advanced tongue cancers (OTSCC) and comparison to standard wide margin surgery (SWMS). Methods: We studied 551 patients with OTSCC treated by CTS and 50 by SWMS. Oncological outcomes were analyzed. A propensity score was performed to compare survival endpoints for the two cohorts. Results: In the CTS group, survival and prognosis were significantly associated with positive lymph-nodes, extranodal extension, depth of invasion and involvement of the soft tissue connecting the tongue primary tumor to neck lymph nodes (T-N tract), independently from the center performing the surgery. SWMS versus CTS showed a HR Cause-Specific Survival (CSS) of 3.24 (95% CI: 1.71-6.11; p < 0.001); HR Loco-Regional Recurrence Free Survival (LRRFS) of 2.54 (95% CI: 1.47-4.40; p < 0.001); HR Overall Survival (OS) of 0.11 (95% CI: 0.01-0.77; p = 0.03). Conclusion: Performing the CTS could provide better CSS and LRRFS than SWMS regardless of the center performing the surgery, in advanced OTSSC

Current trends on subtotal petrosectomy with cochlear implantation in recalcitrant chronic middle ear disorders

Objective. To establish the safety and effectiveness of subtotal petrosectomy with cochlear implantation in patients affected by chronic middle ear disorders to refractory to previous surgical treatments. Methods. A multicentre, retrospective study was conducted on patients affected by recalcitrant chronic middle ear disorders who underwent cochlear implantation in combi-nation with subtotal petrosectomy. Patients’ details were collected from databases of 11 Italian tertiary referral centres. Additionally, a review of the most updated literature was carried out. Results. 55 patients were included with a mean follow-up time of 44 months. Cholestea-toma was the most common middle ear recurrent pathology and 50.9% of patients had an open cavity. 80% of patients underwent a single stage surgery. One case of explantation for device failure was reported among the 7 patients with post-operative complications. Conclusions. Subtotal petrosectomy with cochlear implantation is a benchmark for management of patients with recalcitrant chronic middle ear disorders. A single stage procedure is the most recommended strategy. Optimal follow-up is still debated. Further studies are required to investigate the role of this surgery in paediatric patients. © Società Italiana di Otorinolaringoiatria e Chirurgia Cervico-Facciale

Exploring the relationships between elasticity and crystal chemistry in oxide spinels

“Mineral physics” is the science of materials (minerals) that compose the Earth’s interior and generally refers to the study of the physical properties of minerals typically at high pressure and/or temperature conditions. “Crystal chemistry” is the study of the relationships between structure and composition of crystalline materials. These two subjects evolved independently of each other and the attempts to relate them were in fact only partial. The aim of this thesis is the study of the elastic properties of a set of oxide spinels with different crystal-chemistry in order to quantify and understand the relationships between elasticity and crystal chemistry. The logic path followed during the work can be schematized as follow: 1) elasticity in the system MgAl2O4 as a function of cation distribution in the non-equivalent polyhedral sites. 2) elasticity in the system (Mg,Mn)Al2O4 as a function of the Mn2+ --> Mg substitution. 3) elasticity in the system (Mg,Fe2+)Al2O4 as a function of the Fe2+ --> Mg substitution. 4) elasticity in the system (Mg,Fe2+)Al2O4 as a function of applied pressure. The results of this thesis highlights the non-trivial effect of chemical substitution which can affect the elastic properties of oxide spinels in complicated way. In particular it has been demonstrated that even a small amount of transition elements (Mn and Fe to a greater extent) may have a large influence on the elastic properties in the (Mg,Mn)Al2O4 and (Mg,Fe)Al2O4. In addition the elastic parameters may behave non-monotonically as a function of chemical substitution. Cation disorder has much less influence on the elasticity with respect to chemical substitution. The elasticity of the system (Mg,Mn)Al2O4 has been (at least in part) explained using the polyhedral approach which allows the description of the bulk properties in terms of polyhedral contribution. This approach however failed to explain the elasticity of the system (Mg,Fe2+)Al2O4 suggesting that the physics behind the Fe2+ --> Mg substitution is more complex than the Mn2+ --> Mg substitution

Mapping the spectral and mineralogical variability of lunar breccia meteorite NWA 13859 by VNIR reflectance spectrosco-py

&lt;p&gt;Supplemetary materials for the &quot;Mapping the spectral and mineralogical variability of lunar breccia meteorite NWA 13859 by VNIR reflectance spectroscopy&quot;&lt;/p&gt; &lt;p&gt;&nbsp;&lt;/p&gt; &lt;p&gt;E. Bruschini, C. Carli, F. Tosi&lt;/p&gt

Fe–Mg substitution in aluminate spinels. Effects on elastic properties investigated by Brillouin scattering

We investigated by a multi-analytical approach (Brillouin scattering, X-ray diffraction and electron microprobe) the dependence of the elastic properties on the chemical composition of six spinels in the series (Mg1−x,Fex)Al2O4(0 ≤ x ≤ 0.5). With the exception of C12, all the elastic moduli (C11, C44, KS0and G) are insensitive to chemical composition for low iron concentration, while they decrease linearly for higher Fe2+content. Only C12shows a continuous linear increase with increasing Fe2+across the whole compositional range under investigation. The high cation disorder showed by the sample with x = 0.202 has little or no influence on the elastic parameters. The range 0.202 < x < 0.388 bounds the percolation threshold (pc) for nearest neighbor interaction of Fe in the cation sublattices of the spinel structure. Below x = 0.202, the iron atoms are diluted in the system and far from each other, and the elastic moduli are nearly constant. Above x = 0.388, Fe atoms form extended interconnected clusters and show a cooperative behavior thus affecting the single-crystal elastic moduli. The elastic anisotropy largely increases with the introduction of Fe2+in substitution of magnesium in spinel. This behavior is different with respect to other spinels containing transition metals such as Mn2+and Co2+

Elasticity of spinels in the system (Mg,Fe2+)Al2O4: The effect of Fe-Mg substitution up to 10 GPa

According to the pyrolite compositional model, spinel-structured compounds are among the most abundant materials of the Earth’s mantle (especially in the transition zone between 410 and 660 km depth). It is widely known that iron is the most abundant transition metal in the minerals of the mantle. However, the exact iron content and its heterogeneity in the mantle is still a matter of debate. Fe concentration plays a crucial role in determining a wide range of physical properties of the main minerals of the mantle, In particular it was recently pointed out that heterogeneity of Fe content controls the shear waves velocity much more than temperature variations. We performed Brillouin-scattering measurements at ambient conditions and at high pressure up to 10 GPa of a set of synthetic oxide spinels in the system MgAl2O4 (Spinel s.s.) – FeAl2O4 (Hercynite) in order to assess how the Fe2+ → Mg substitution affects the elastic properties of spinel-structured oxides at high pressure. Our results reveal a strong deviation from linearity of the elastic tensor components (Cij’s) as a function of divalent iron content already at low Fe2+ region. With increasing Fe content C11 and C44 show an initial increase followed by a decrease at Fe/(Fe+Mg) > 0.1-0.2 (which is comparable with Fe content in the mantle ringwoodite). With our results we have placed, for the first time, quantitative constraints on the effect of Fe-Mg substitution on the elastic properties of spinel-hercynite solid solutions. Given that the iron content strongly affects the elastic properties of spinel-structured oxides, our results raise the important question of which is the role of both the chemical variability and the cations distribution, especially in terms of Fe → Mg substitution, on the elastic properties of the spinel-structured transition zone silicates (i.e. ringwoodite and wadsleyite). This question needs to be addressed in order to put constrains on the interpretation of seismic features (in particular from seismic tomography) of the mantle in terms of chemical composition and heterogeneity

The elasticity of MgAl2O4–MnAl2O4 spinels by Brillouin scattering and an empirical approach for bulk modulus prediction

The elastic constants Cij of a set of synthetic single crystals belonging to the join MgAl2O4–MnAl2O4 (spinel sensu stricto–galaxite) were determined by Brillouin spectroscopy at ambient conditions. The C11 component tends to remain constant for Mg-rich compositions (XMn < 0.5) and decreases in Mn-rich compositions, whereas C12 increases and C44 decreases almost linearly from MgAl2O4 to MnAl2O4. The bulk modulus KS is weakly dependent upon Mg-Mn substitution within experimental uncertainties, whereas the shear modulus G decreases with increasing Mn2+ content. For MnAl2O4, C11 = 271.3(1.3) GPa, C12 = 164.8(1.3) GPa, C44 = 124.9(5) GPa, KS = 200(1) GPa, and G = 88.7(5) GPa. Based on the “polyhedral approach,” we developed a model that describes the crystal bulk moduli of the MgAl2O4–MnAl2O4 spinels in terms of their cation distribution and the polyhedral bulk moduli of the different cations. We refined a set of values for the effective polyhedral bulk modulus of Mg, Mn2+, and Al in tetrahedral (T) and octahedral (M) sites, which span from 153 to 270 GPa ranking as follows: KMMn < KMMg < KTMg ≈ KTMn < KMAl << KTAl. Crystal bulk modulus was perfectly reproduced within 0.1% for all Mn2+-bearing samples. We also found a high linear correlation between the effective polyhedral bulk modulus and the ionic potential, IP, of the coordinating cations: Kij (GPa) = 20(2) IP + 108(10) (where i indicates the cation and j the polyhedral site). We tested this simple correlation by calculating the specific effective polyhedral bulk modulus of several cations in T and M coordination and then predicting the crystal bulk modulus for several spinel compositions. The success of our simple correlation in modeling the bulk modulus of spinels outside the MgAl2O4–MnAl2O4 system is encouraging, and suggests that the relationships between chemical composition, cation distribution and elastic properties in spinel-structured minerals and materials can indeed be expressed by relatively simple models

Pressure-volume equation of state for chromite and magnesiochromite: A single-crystal X-ray diffraction investigation

The pressure-volume equation of state for the two spinel end-member compositions chromite FeCr2O4 and magnesiochromite MgCr2O4 was determined for flux-grown synthetic single crystals at room temperature up to 8.2 and 9.2 GPa, respectively, by single-crystal X-ray diffraction using a diamondanvil cell. The pressure-volume data show that the linear volume compressibility (here used only for purpose of comparison), calculated as beta(V) = vertical bar[Delta V/V-0)/Delta P]vertical bar, is 0.00468 and 0.00470 GPa(-1), for chromite and magnesiochromite, respectively, with a negligible difference below 0.5%. The experimental data were fitted to a third-order Birch-Murnaghan equation of state (BM3) allowing a simultaneous refining of the following coefficients: V-0 = 588.47(4) angstrom(3), K-T0 = 184.8(1.7) GPa, and K' = 6.1(5) for chromite and V-0 = 579.30(4) angstrom(3), K-T0 = 182.5(1.4) GPa, and K' = 5.8(4) for magnesiochromite. The difference in K-T0 is reduced to <1.5% going from Fe to Mg end-member composition, whereas the first pressure derivative seems not to be affected by the chemical variability. The limited difference in the equation of state coefficients recorded for FeCr2O4 and MgCr2O4 allowed us to fit the pressure-volume data of both to a single BM3 equation, resulting in a K-T0 = 184.4(2.2) GPa and K' = 5.7(6)