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The Debye scattering equation (DSE) [Debye (1915). Ann. Phys.351, 809–823] is widely used for analyzing total scattering data of nanocrystalline materials in reciprocal space. In its modified form (MDSE) [Cervellino et al. (2010). J. Appl. Cryst.43, 1543–1547], it includes contributions from uncorrelated thermal agitation terms and, for defective crystalline nanoparticles (NPs), average site‐occupancy factors (s.o.f.'s). The s.o.f.'s were introduced heuristically and no theoretical demonstration was provided. This paper presents in detail such a demonstration, corrects a glitch present in the original MDSE, and discusses the s.o.f.'s physical significance. Three new MDSE expressions are given that refer to distinct defective NP ensembles characterized by: (i) vacant sites with uncorrelated constant site‐occupancy probability; (ii) vacant sites with a fixed number of randomly distributed atoms; (iii) self‐excluding (disordered) positional sites. For all these cases, beneficial aspects and shortcomings of introducing s.o.f.'s as free refinable parameters are demonstrated. The theoretical analysis is supported by numerical simulations performed by comparing the corrected MDSE profiles and the ones based on atomistic modeling of a large number of NPs, satisfying the structural conditions described in (i)–(iii). [ABSTRACT FROM AUTHOR]

We propose a novel method alternative to the classical Dynamic Light Scattering (DLS) technique for performing particle sizing on diluted dispersions of nanosized particles. Differently from DLS, which works by determining the correlation function of the intensity scattered by the sample, our method does not require the use of a correlator because it exploits the behavior of the variance (VAR) of the scattered signal as a function of the sampling time Δt. By using a wide range of sampling times Δtmin ≪ τc ≪ Δtmax, it is possible to recover the correlation time τc of the scattered field and, in turn (by using the Stokes–Einstein relation), the hydrodynamic diameter of the particles. The new method is endowed with an analytical expression for the error bars associated with to the VAR data. Extensive computer simulations carried out on monodisperse and narrow polydisperse samples show that VAR and DLS techniques provide fairly similar performances. The same results were obtained on calibrated polystyrene spheres and fluorescent perovskite nanoparticles tested with different setups and detection schemes. [ABSTRACT FROM AUTHOR]

Volcanic arcs above subduction zones are thought to be the principal locations where juvenile magmatic crust forms and is refined to become continental crust with an andesitic composition. During this refinement mechanism, the formation of dense garnet pyroxenites (arclogites), represented by high-pressure cumulates and restites after partial melting, leads to the delamination of the lower arc crust. The Mercaderes-Río Mayo area in southern Colombia is the only known locality in an active volcanic arc where arclogitic xenoliths have been recovered. These xenoliths are entrained in the Granatifera Tuff, a late Cenozoic volcanic vent, and they mainly consist of garnet, clinopyroxene, amphibole, plagioclase, rarely scapolite, and accessory mineral inclusions of rutile, apatite, zircons, and quartz. Moreover, the arclogites are also characterized by the presence of melt inclusions (MI), which are mainly found within garnet, but can be also observed in amphibole, plagioclase, clinopyroxene, and scapolite. The glasses measured for the MI in garnet and scapolite typically have SiO2 contents >57 wt.%, ranging from andesite to rhyolite in composition. Petrographic and geochemical investigations allowed to discriminate between cumulitic and restitic arclogites, with the latter showing the concomitant presence of primary MI and quartz inclusions within the peritectic garnets. Therefore, our study provides for the first time a strong evidence, at the microscale, for the anatectic origin of some arclogitic xenoliths. Pressure and temperature conditions for the studied arclogites were estimated by intracrystalline geothermometry, elastic geothermobarometry, phase equilibria modelling and classical Fe–Mg exchange between garnet and clinopyroxene. Results fall within the range of 960°C to 1150°C and 1.6 to 1.9 GPa for most samples. We suggest that the investigated arclogites derive from the root of the active Colombian volcanic arc, where differentiation processes from mantle-derived melts and lower crust anatexis occur in close association. [ABSTRACT FROM AUTHOR]

Light scattering and turbidimetry techniques are classical tools for characterizing the dynamics and structure of single nanoparticles or nanostructured networks. They work by analyzing, as a function of time (Dynamic Light Scattering, DLS) or angles (Static Light Scattering, SLS), the light scattered by a sample, or measuring, as a function of the wavelength, the intensity scattered over the entire solid angle when the sample is illuminated with white light (Multi Wavelength Turbidimetry, MWT). Light scattering methods probe different length scales, in the ranges of ~ 5 – 500   nm (DLS), or ~ 0.1 – 5   μ m (Wide Angle SLS), or ~ 1 – 100   μ m (Low Angle SLS), and some of them can be operated in a time-resolved mode, with the possibility of characterizing not only stationary, but also aggregating, polymerizing, or self-assembling samples. Thus, the combined use of these techniques represents a powerful approach for studying systems characterized by very different length scales. In this work, we will review some typical applications of these methods, ranging from the field of colloidal fractal aggregation to the polymerization of biologic networks made of randomly entangled nanosized fibers. We will also discuss the opportunity of combining together different scattering techniques, emphasizing the advantages of a global analysis with respect to single-methods data processing. [ABSTRACT FROM AUTHOR]

Let L / K be a finite Galois extension of p -adic fields with group G. It is well-known that O L contains a free O K [ G ] -submodule of finite index. We study the minimal index of such a free submodule, and determine it exactly in several cases, including for any cyclic extension of degree p of p -adic fields. [ABSTRACT FROM AUTHOR]

A new inversion method, devised by modification of the nonlinear iterative method originally proposed by Chahine [J. Opt. Soc. Am. 58, 1634 (1968)] is applied to the inversion of low-angle elastic light-scattering data. The algorithm was tested by computer simulations carried out within the wave-vector range 2.5 x [10.sup.2]-2.5 x [10.sup.4] [cm.sup.-1]. The particle-size distributions were recovered in the 0.70-77-[[micro]meter] range of radii. Compared with the original method of Chahine, this algorithm is much more stable and reliable with respect to random noise, improves the overall reliability of the fitting, and allows both number and weight particle-size distributions to be retrieved accurately. When the performances of the method are investigated with respect to the noise, the results of the simulations show that the particle-size distributions can be recovered accurately up to noise levels of several rms percent. Key words: Particle sizing, inversion algorithm, elastic light scattering.

Particle-size distribution and the concentration of polystyrene particles suspended in water were accurately recovered from the inversion of spectral extinction data measured with a commercial spectrophotometer. The instrument was modified by placing a spatial filter in the collection optics to prevent low-angle scattered light from affecting the measurement of transmitted power. The data were inverted by use of a nonlinear iterative algorithm. When the extinction coefficient is measured in the k range of 0.3-1.1 [[micro]meter], the particle distributions can be retrieved over a diameter range of 0.6-2.8 [[micro]meter] for a wide interval of sample concentrations. The average diameters are recovered with a precision of better than [+ or -]1% and with accuracies consistent with the uncertainties by which the nominal diameters are known. The relative standard deviations of distributions corresponding to monodisperse samples are [+ or -]5-10%, whereas the accuracy on the measured concentrations is [approximately]5%. Key words: Particle sizing, inversion algorithm, spectral extinction.

Partial melting up to ultra high temperature (UHT) conditions is one of the major processes for the geochemical differentiation and reworking of the mid‐ to lower continental crust, with relevant implications on its rheological behaviour. UHT granulites from the Gruf Complex (European Central Alps) display garnet and sapphirine porphyroblasts containing a variety of primary melt inclusions (MI). Typically, MI in garnet occur as glassy and polycrystalline inclusions (i.e. nanogranitoids), the latter commonly organized in mm‐sized clusters associated with primary fluid inclusions (FI). Nanogranitoids are characterized by an elliptical faceted shape, with variable sizes ranging from 2 to 115 µm, while glassy inclusions show negative crystal shapes that usually never exceed 15 µm in diameter and present CO2‐rich shrinkage bubbles. The characteristic mineral assemblage observed in nanogranitoids consists of quartz, biotite, muscovite, plagioclase, K‐feldspar, kokchetavite and rarely aluminosilicates. Glassy and re‐homogenized MI are peraluminous and rhyolitic in composition, with SiO2 = 69 − 80 wt% and Na2O + K2O = 5 − 12 wt%. Commonly, the analysed MI have very high K2O (>6 wt%) and very low Na2O (<2 wt%) contents, indicative for potassic to ultrapotassic melts. Measured H2O contents of the melts range from 2.9 to 8.8 wt%, whereas CO2 concentrations are between 160 and 1738 ppm. Accordingly, calculated viscosities for re‐homogenized MI vary between 104 and 105 Pa·s. Related primary FI mainly contain CO2, with rare occurrence of CO and N2, and are commonly associated with quartz, as well as different carbonates and phyllosilicates. It is assumed that the source for the carbonic fluid was external and probably related to the degassing lithospheric mantle. Consequently, it is argued that anatexis was initially triggered by incongruent dehydration melting reactions involving biotite breakdown and proceeded in the presence of an externally derived COH‐bearing fluid. The coexistence of COH‐bearing fluid and MI indicates that partial melting occurred under conditions of fluid − melt immiscibility. Potassic to ultrapotassic MI in UHT granulites suggests that lower crustal anatexis may play a significant role in the redistribution of heat‐producing elements (such as K2O), potentially influencing the thermal structure of the continental crust. [ABSTRACT FROM AUTHOR]

Background: Disease awareness is a challenge in the management of chronic obstructive pulmonary disease (COPD). Objectives: The aim of this analysis was to explore the association between COPD optimal and suboptimal awareness, clinical parameters, and the following patient-reported outcomes: modified Medical Research Council (mMRC), Treatment Satisfaction Questionnaire (TSQM-9), COPD Assessment Test (CAT), Morisky Medication-Taking Adherence Scale (MMAS-4), and Brief Illness Perception Questionnaire (B-IPQ). Methods: This post hoc analysis of the SAT study included all enrolled patients for whom awareness (Disease Awareness in COPD Questionnaire - DACQ) was assessed at baseline and 12 months. DACQ scores =80 were considered an indicator of an optimal awareness. Results: 367 patients (25.8% women, median age 72 years) were included in the analysis. At enrollment, 74 patients (20.2%) had a DACQ score =80. Patients with suboptimal awareness, compared to those in which awareness was optimal, had higher median scores for CAT (p = 0.0001) and mMRC (p = 0.0031), a lower median TSQM-9 global score (p < 0.0001), and higher median B-IPQ score (p < 0.0001). The proportion of patients who had exacerbations during the previous year was higher in patients with suboptimal COPD awareness than in those with DACQ score =80 (42.8 vs. 21.4%, p = 0.0009). During the 12-month observation period, illness perception, adherence, and treatment satisfaction were found to be independent factors significantly associated with level of disease awareness. Conclusion: The results of our post hoc analysis suggest that patients' awareness of their COPD disease is related to both clinical outcomes and how they perceive and manage their condition. [ABSTRACT FROM AUTHOR]

The occurrence of an amorphous calcium phosphate layer covering the crystalline apatite core has been suggested to be an intrinsic feature of both bone mineral and synthetic biomimetic analogs. However, an exahustive quantitative picture of the amorphous-crystalline relationship in these materials is still missing. Here, we present a multiple scale modelling that combines small-angle X-ray scattering (SAXS) and synchrotron wide-angle X-ray total scattering (WAXTS) analyses to investigate the amorphous-crystalline spatial interplay in bone sample and biomimetic carbonated nano-apatites. SAXS analysis indicates the presence of a single morphology consisting of tiny nanoplates (NPLs) and provides a measure of their thickness (falling in the 3–5 nm range). WAXTS analysis was performed by developing atomistic models of apatite NPLs incorporating lattice strain, mostly attributed to the carbonate content, and calculating the X-ray patterns using the Debye Scattering Equation. Upon model optimization, the size and strain parameters of the crystalline platelets were derived and the amorphous component, co-existing with the crystalline one, separated and quantified (in the 23–33 wt% range). Notably, the thickness of the apatite core was found to exhibit nearly null (bone) or minor (< 0.5 nm, biomimetic samples) deviations from that of the entire NPLs, suggesting that the amorphous material remains predominantly distributed along the lateral sides of the NPLs, in a core-crown-like arrangement. The lattice strain analysis indicates a significant stiffness along the c axis, which is comparable in bone and synthetic samples, and larger deformations in the other directions. Current models of bone mineral and biomimetic nanoapatites suggest the occurrence of an amorphous layer covering the apatitic crystalline nanoplates in a core-shell arrangement. By combining X-ray scattering techniques in the small and wide angle regions, we propose a joint atomic-to-nanometre scale modelling to investigate the amorphous-crystalline interplay within the nanoplates. Estimates are extracted for the thickness of the entire nanoplates and the crystalline core, together with the quantification of the amorphous fraction and apatite lattice strain. Based on the thickness matching, the location of the amorphous material mostly along the edges of the nanoplates is inferred, with a vanishing or very thin layer in the thickness direction, suggesting a core-crown-like arrangement, with possible implications on the mineral surface reactivity. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The kinetics of release of fibrinopeptide A (FPA) and B (FPB) by thrombin were investigated on unfractionated fibrinogen samples as a function of CaCl2 concentration. A possible correlation to the inherent polydispersity of fibrinogen (FG) samples and the implications of these findings for FG structure, functional relationship and for the process of fibrin formation are discussed.

We investigate the inclusions hosted in peritectic garnet from metapelitic migmatites of the Kinzigite Formation (Ivrea Zone, NW Italy) to evaluate the starting composition of the anatectic melt and fluid regime during anatexis throughout the upper amphibolite facies, transition, and granulite facies zones. Inclusions have negative crystal shapes, sizes from 2 to 10 μm and are regularly distributed in the core of the garnet. Microstructural and micro‐Raman investigations indicate the presence of two types of inclusions: crystallized silicate melt inclusions (i.e., nanogranitoids, NI), and fluid inclusions (FI). Microstructural evidence suggests that FI and NI coexist in the same cluster and are primary (i.e., were trapped simultaneously during garnet growth). FI have similar compositions in the three zones and comprise variable proportions of CO2, CH4, and N2, commonly with siderite, pyrophyllite, and kaolinite, suggesting a COHN composition of the trapped fluid. The mineral assemblage in the NI contains K‐feldspar, plagioclase, quartz, biotite, muscovite, chlorite, graphite and, rarely, calcite. Polymorphs such as kumdykolite, cristobalite, tridymite, and less commonly kokchetavite, were also found. Rehomogenized NI from the different zones show that all the melts are leucogranitic but have slightly different compositions. In samples from the upper amphibolite facies, melts are less mafic (FeO + MgO = 2.0–3.4 wt%), contain 860–1700 ppm CO2 and reach the highest H2O contents (6.5–10 wt%). In the transition zone melts have intermediate H2O (4.8–8.5 wt%), CO2 (457–1534 ppm) and maficity (FeO + MgO = 2.3–3.9 wt%). In contrast, melts at granulite facies reach highest CaO, FeO + MgO (3.2–4.7 wt%), and CO2 (up to 2,400 ppm), with H2O contents comparable (5.4–8.3 wt%) to the other two zones. Our results represent the first clear evidence for carbonic fluid‐present melting in the Ivrea Zone. Anatexis of metapelites occurred through muscovite and biotite breakdown melting in the presence of a COH fluid, in a situation of fluid–melt immiscibility. The fluid is assumed to have been internally derived, produced initially by devolatilization of hydrous silicates in the graphitic protolith, then as a result of oxidation of carbon by consumption of Fe3+‐bearing biotite during melting. Variations in the compositions of the melts are interpreted to result from higher T of melting. The H2O contents of the melts throughout the three zones are higher than usually assumed for initial H2O contents of anatectic melts. The CO2 contents are highest at granulite facies, and show that carbon‐contents of crustal magmas are not negligible at high T. The activity of H2O of the fluid dissolved in granitic melts decreases with increasing metamorphic grade. Carbonic fluid‐present melting of the deep continental crust represents, together with hydrate‐breakdown melting reactions, an important process in the origin of crustal anatectic granitoids. [ABSTRACT FROM AUTHOR]

The third edition of the To.Sca.Lake Summer School, co-sponsored by ICDD, was organized on the Como Lake shore in Northern Italy, and has seen the participation of more than 50 attendees from four different continents. The main topic was Total Scattering Analysis in the real and reciprocal spaces (by the Pair Distribution Function and the Debye Scattering Equation approaches, respectively). with additional contributions on Small Angle X-ray Scattering and Light Scattering methods, the latter proposed in the static and dynamic modes. [ABSTRACT FROM AUTHOR]

The garnet-biotite-sillimanite enclaves from El Hoyazo are quenched anatectic metapelites found within peraluminous dacites (Betic Cordillera, SE Spain), representing a residual lower crust in the area after 40–60% of melt extraction. Anatexis occurred concomitantly with deformation in a regional metamorphic setting during the Upper Miocene at the base of the continental crust. Previous studies have provided detailed information on the pressure-temperature evolution, the sequence of melting reactions, and associated melt proportions and compositions. They show that enclaves mostly record peak metamorphic assemblages, mineral compositions, and, likely, microstructures, with minor changes upon entrapment within the dacite magma and rapid ascent and extrusion. The enclaves still preserve a proportion of the primary melt, that solidified to glass in abundant melt inclusions (MI) and matrix melt, permitting the study of the microstructural relationships between melt and residue. This study focuses on the geometry of the glass network at the microscale that, combined with the previously reported anatectic history, helps shed light on the mechanisms and history of melt drainage from these rocks. A representative sample of the enclaves was investigated by synchrotron μ-XRF and scanning electron microscopy to map the distribution of glass and minerals on three thin sections cut perpendicularly to the foliation. The combination of major and trace element μ-XRF distribution maps and detailed backscattered electron images evidence the presence of a pervasive and mostly interconnected glass network through the studied centimeter-scale sections. Interconnection is due to the crosscutting of films and glass-rich domains oriented parallel and at high angle with foliation. Although enclaves lost ~40–60% of melt, they still contain ~10–15% of glass, with a considerable proportion of it stored within the Mix, which is an aggregate of micrometer-sized fibrolitic sillimanite and glass. The distribution of glass (former melt) is not in textural equilibrium with the solid residue and resembles the interconnected network of deformation bands observed in migmatites of anatectic terranes at the mesoscale. Microstructural studies of melt pseudomorphs in migmatites and granulites of anatectic terranes are scarce, but the following remarkable interpretations can be made combining our observations of these enclaves: melt formed an interconnected network during anatexis that permitted melt segregation and extraction, though melt-residue textural disequilibrium is the rule rather than the exception. The proportion of melt present in residual migmatites can be much higher than the permeability threshold for crustal protoliths; in this particular study, two reasons for this might be that (1) melt was still being produced and flowing through the residual migmatite right before disaggregation and inclusion within the host dacite, where additional melt drainage was impeded by the hydrostatic stress field, and (2) a particular microstructure produced at the onset of anatexis, such as the Mix, acted as a trap for melt impeding or delaying melt segregation. [ABSTRACT FROM AUTHOR]

A novel instrument that is capable of taking spectral extinction measurements over long optical paths (approximately 1-100 m) in the UV, visible, and IR ranges is described. The instrument is fully automated, and the extinction spectrum is acquired in almost real time (approximately 5-10 s) with a resolution of ~3 nm. Its sensitivity and accuracy were estimated by tests carried out in a clean room that showed that, for optical paths between 50 and 100 m, the extinction coefficient can be detected at levels of ~[10.sup.-5] [m.sup.-1]. Tests carried out on calibrated latex particles showed that, when it was combined with an appropriate inversion method, the technique could be profitably applied to characterize airborne particulate distributions. By carrying out measurements over optical paths of ~100 m, the instrument is also capable of detecting extinction coefficients that are due to aerosol concentrations well below the limits imposed by the European Economic Community for atmospheric pollution (150 [micro]g/[m.sup.3]). Scaled over optical paths of ~10 m, the limit imposed for particle emissions from industrial plants (10 mg/[m.sup.3]) can also be detected sensitively. OCIS codes: 010.1110, 010.1320, 100.3190, 280.0280, 280.1120, 290.2200.

We present a PC-based multi-tau software correlator suitable for processing dynamic light-scattering data. The correlator is based on a simple algorithm that was developed with the graphical programming language LabVIEW, according to which the incoming data are processed on line without any storage on the hard disk. By use of a standard photon-counting unit, a National Instruments Model 6602-PCI timer--counter, and a 550-MHz Pentium III personal computer, correlation functions can be worked out in full real-time over time scales of ~5 [micro]s and in batch processing down to time scales of ~300 ns. The latter limit is imposed by the speed of data transfer between the counter and the PC's memory and thus is prone to be progressively reduced with future technological development. Testing of the correlator and evaluation of its performances were carried out by use of dilute solutions of calibrated polystyrene spheres. Our results indicate that the correlation functions are determined with such precision that the corresponding particle diameters can be recovered to within an accuracy of a few percent rms. OCIS codes: 290.5820, 070.6020, 030.5290.

The excitation and emission obtained from an Er3+-doped tellurite glass with embedded silver nanoparticles (SNPs) through nanostructured surfaces consisting of a square lattice of nanoholes (squares or circles) in a silver thin film are addressed. The periodic nanostructures were fabricated with a focused gallium ion beam on a silver thin film deposited onto an Er3+-doped tellurite glass with embedded SNPs. The Er3+ microluminescence spectra were measured in the far field (510- to 590-nm wavelength range). The emission observed through the plasmonic nanoholes is caused by the excitation of the Er3+ ions via extraordinary optical transmission from the periodic nanostructures. Two coupling types are proposed: (i) one between the SNPs and the Er3+ ions (electric dipole type) and (ii) a resonant coupling between the SNPs (localized surface plasmon resonance) and a silver thin film (surface plasmon polariton). These two couplings modify the local field, which improves the emission intensity of Er3+. A dependence of the intensity emission with the geometrical shape of the nanoholes and the number of elements of the square lattice was observed. These findings can be very useful for nanophotonic device applications employing a transparent medium with optical gain. [ABSTRACT FROM AUTHOR]

Lucy–Richardson (LR) is a classical iterative regularization method largely used for the restoration of nonnegative solutions. LR finds applications in many physical problems, such as for the inversion of light scattering data. In these problems, there is often additional information on the true solution that is usually ignored by many restoration methods because the related measurable quantities are likely to be affected by non-negligible noise. In this article we propose a novel Weakly Constrained Lucy–Richardson (WCLR) method which adds a weak constraint to the classical LR by introducing a penalization term, whose strength can be varied over a very large range. The WCLR method is simple and robust as the standard LR, but offers the great advantage of widely stretching the domain range over which the solution can be reliably recovered. Some selected numerical examples prove the performances of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In this work, mixed alkali metaphosphate glasses based on K–Na, Rb–Na, Rb–Li, Cs–Na and Cs–Li combinations were studied by differential scanning calorimetry (DSC), complex impedance spectroscopy, and Raman spectroscopy. DSC analyses show that both the glass transition (Tg) and melting temperatures (Tm) exhibit a clear mixed-ion effect. The ionic conductivity shows a strong mixed-ion effect and decreases by more than six orders of magnitude at room temperature for Rb–Na or Cs–Li alkali pairs. This study confirms that the mixed-ion effect may be explained as a natural consequence of random ion mixing because ion transport is favoured between well-matched energy sites and is impeded due to the structural mismatch between neighbouring sites for dissimilar ions. [ABSTRACT FROM AUTHOR]

A 10 ns time resolution, multi-tau software correlator, capable of computing simultaneous autocorrelation (A-A, B-B) and cross (A-B) correlation functions at count rates up to ~10 MHz, with no data loss, has been developed in LabVIEW and C++ by using the National Instrument timer/counterboard (NI PCIe-6612) and a fast Personal Computer (PC) (Intel Core i7-4790 Processor 3.60 GHz ). The correlator works by using two algorithms: for large lag times (τ & 1 μs), a classical time-mode scheme, based on the measure of the number of pulses per time interval, is used; differently, for τ . 1 μs a photon-mode (PM) scheme is adopted and the correlation function is retrieved from the sequence of the photon arrival times. Single auto- and cross-correlation functions can be processed online in full real time up to count rates of ~1.8 MHz and ~1.2 MHz, respectively. Two autocorrelation (A-A, B-B) and a cross correlation (A-B) functions can be simultaneously processed in full real time only up to count rates of ~750 kHz. At higher count rates, the online processing takes place in a delayed modality, but with no data loss. When tested with simulated correlation data and latex spheres solutions, the overall performances of the correlator appear to be comparable with those of commercial hardware correlators, but with several nontrivial advantages related to its flexibility, low cost, and easy adaptability to future developments of PC and data acquisition technology. [ABSTRACT FROM AUTHOR]

The combination of compressional and shear wave velocity is an important tool in discriminating rock types and identifying residing melts within the continental crust. Here we report the laboratory measurements for Vp and Vs obtained in varying conditions up to those exceeding the beginning of melting (950 °C at 500 MPa confining pressure) on two residual garnet–biotite–sillimanite–cordierite–spinel metapelitic enclaves recovered from the Neogene dacites of Mazarrón (SE Spain). The enclaves preserve widespread interstitial rhyolitic glass as evidence of primary melt extraction. At 500 MPa, the experimental Vp ranges from 7.21 ÷ 7.46 km s − 1 at room temperature to 5.44 km/s at 950 °C. The mean Vs is 4.5 km/s at room temperature with shear-wave splitting of 0.25 ÷ 0.3 km/s, measured along three mutually orthogonal directions. When temperature increases, the Vs evidences a reversible slope change at about 650 °C, and the shear-wave splitting reduces to zero (isotropic material) at 850–950 °C, where the sample Vs is ~ 3.0 km/s. The Vp anisotropy is 7–10% up to 700 °C increasing to ~ 20% at 950 °C, while the Vs anisotropy continuously decreases with temperature from 5% to 7% at room temperature to zero at 950 °C. No mineral reactions are observed up to 650–700 °C; however, microstructure equilibrates due to the relaxation of the primary glass at the glass transition temperature. Between 850 °C and 950 °C, a new melting reaction is observed producing biotite + spinel + ilmenite + plagioclase + melt. At melting, the rock becomes isotropic for Vs, and Poisson's ratio increases to 0.30. Our seismic data show that the seismic signature of high grade metapelitic rocks is similar to that of mafic materials. The evolution of Vp and Vs at melting conditions is compatible with the geophysical data of the area, supporting the hypothesis of the current existence of anatectic melts at intermediate depths of the Alborán domain. [ABSTRACT FROM AUTHOR]

Background: Mass spectrometry (MS) is producing high volumes of data supporting oncological sciences, especially for translational research. Most of related elaborations can be carried out by combining existing tools at different levels, but little is currently available for the automation of the fundamental steps. For the analysis of MALDI/TOF spectra, a number of pre-processing steps are required, including joining of isotopic abundances for a given molecular species, normalization of signals against an internal standard, background noise removal, averaging multiple spectra from the same sample, and aligning spectra from different samples. In this paper, we present Geena 2, a public software tool for the automated execution of these pre-processing steps for MALDI/TOF spectra. Results: Geena 2 has been developed in a Linux-Apache-MySQL-PHP web development environment, with scripts in PHP and Perl. Input and output are managed as simple formats that can be consumed by any database system and spreadsheet software. Input data may also be stored in a MySQL database. Processing methods are based on original heuristic algorithms which are introduced in the paper. Three simple and intuitive web interfaces are available: the Standard Search Interface, which allows a complete control over all parameters, the Bright Search Interface, which leaves to the user the possibility to tune parameters for alignment of spectra, and the Quick Search Interface, which limits the number of parameters to a minimum by using default values for the majority of parameters. Geena 2 has been utilized, in conjunction with a statistical analysis tool, in three published experimental works: a proteomic study on the effects of long-term cryopreservation on the low molecular weight fraction of serum proteome, and two retrospective serum proteomic studies, one on the risk of developing breat cancer in patients affected by gross cystic disease of the breast (GCDB) and the other for the identification of a predictor of breast cancer mortality following breast cancer surgery, whose results were validated by ELISA, a completely alternative method. Conclusions: Geena 2 is a public tool for the automated pre-processing of MS data originated by MALDI/TOF instruments, with a simple and intuitive web interface. It is now under active development for the inclusion of further filtering options and for the adoption of standard formats for MS spectra. [ABSTRACT FROM AUTHOR]

We present a method for fluid velocimetry based on a single-exposure analysis of the streak speckle pattern generated by sub-micron tracking particles illuminated with coherent light. It works in real-time and provides two dimensional velocity mappings in the direction orthogonal to the optical axis, independently of particle concentration and size. It is immune of any spurious light acting as undesired heterodyne signal and can probe velocities much higher (~three orders of magnitude) than methods based on double-exposure analysis. The method has been tested by using rigid diffusers of different heterodyne strength and applied to map the flow of a confined fluid. [ABSTRACT FROM AUTHOR]

Abstract: The complex electrical impedance of a garnet–biotite–sillimanite residual enclave in the Neogene dacite of El Hoyazo (SE Spain) has been determined up to 978°C at 200–300MPa. This well studied material represents a direct sampling of the Alborán Domain thinned lower crust undergoing partial melting. The paragenesis is garnet+biotite+sillimanite+plagioclase+graphite±cordierite coexisting with widespread (~10wt.%) rhyolitic melt occurring as inclusions and interstitial glass and developed during regional anatexis at 850±50°C and 500–700MPa. The samples were used in cyclic measurements consisting in heating–cooling ramps at progressively higher maximum temperature to observe the effect of reactions on conductivity. In the first cycle up to 850°C at 2–3kbar, re-melting of the interstitial glass is achieved with no additional reactions and logarithmic conductivity (S/m) is up to −1.5. At T>950°C new melt with orthopyroxene+ilmenite is produced from biotite partial breakdown and the logarithmic conductivity (S/m) is up to −0.7. Application of mixing models as Hashin–Shtrikman bounds or Archie''s Law, shows that once interconnected, melt controls the electrical conductivity of the enclave. The electrical conductivity of the rock can be simulated with the electrical conductivity data obtained on the starting Matrix glass of the enclave and with the new melt. Our experimental results obtained on a graphitic metasedimentary material evidence show that graphite does not contribute to the conductivity enhancement and that the electrical anomaly observed below the Betics can be explained as effect of partial melting of a residual crust. Comparison with previous works on mafic granulites shows that similar conductivity values can be achieved both by melting of a residual felsic crust or by melting of mafic materials and suggests that pelitic rocks can be more common at deep levels than expected. [Copyright &y& Elsevier]

Terra Nova, 22, 347–353, 2010 Thermal pressurization of pore fluid is one of the possible mechanisms responsible for dynamic weakening in landslides and earthquakes, but, to date, has not been reproduced in the laboratory. Here, we report high-velocity experiments performed in a rotary shear friction apparatus on smectite-rich gouges from the 1963 Vaiont landslide (Italy). The gouges were slid under 1 MPa normal stress, for displacements up to 30 m and a slip rate of 1.31 m s−1 under room-humidity and water-saturated conditions. Sample dilatancy was observed in room-humidity runs after ∼3–4 m of slip, concomitant with an increase in normal stress and a decrease in shear stress. Mineralogical and microstructural investigations suggest that dilatancy resulted from expansion of the H2O released by the collapse of the smectite structure due to frictional heating of the slipping zone at T >200 °C. We conclude that sample dilatancy is due to thermal pressurization of the clay-rich gouge. [ABSTRACT FROM AUTHOR]

Abstract: Seismic techniques provide unique tools to investigate the structure and, in combination with petrological, geochemical and petrophysical study, the composition of the lower crust. Controversies can be solved with comparative study of metamorphic terrains or xenoliths that occur adjacent to areas where seismic refraction/reflection data are available. Xenoliths represent a direct sampling of the inaccessible lower crust at the time of the volcanism, whilst exposed crustal sections can only be used as analogue of present day lower crust. The present study is focused on the measurements of compressional wave velocities up to conditions exceeding the beginning of melting (950 °C at 500 MPa confining pressure) on three garnet–biotite–sillimanite metapelitic xenoliths recovered from the Neogene dacites of El Hoyazo (SE Spain). They preserve widespread interstitial rhyolitic glass as evidence of primary melt extraction and represent the best example of partially molten lower crust in the Alborán Domain. The influence of glass on Vp is primarily reflected by anomalous positive dVp/dT while heating with velocity increasing at 500 MPa from 4.98 to 5.50 km s−1 at room temperature to 5.85–6.79 km s−1 at 650–700 °C. This corresponds to the glass transition where all the grain boundaries and most of the pores within the glass are closed. After this point, the velocity decreases to 6.2–6.5 km s−1 at 950 °C where re-melting of the glass is achieved and additional partial melt produced. On cooling, the behavior is normal with negative dVp/dT. After the thermal treatment velocities are 30% higher (6.07–7.21 km s−1) and reveal that in the presence of intergranular melt velocity measurements at room temperature cannot be extrapolated to high temperatures. P-waves measured at melting conditions are in agreement with deep seismic refraction data and tomography in the area and corroborate the hypothesis that partial melts are actually present in Alborán lower crust. [Copyright &y& Elsevier]

We present a hardware simulator ideal for testing digital correlators in photon correlation spectroscopy. By using a PCI-6534 National Instrument I/O board, a personal computer (1.5 GHz Pentium 4), and an original algorithm developed in LabVIEW (National Instrument™), we realized an instrument capable of delivering a continuous stream of transistor-transistor logic pulses with the desired statistical properties over one or more channels. The pulse resolution could be set to values multiple of the clock period Δt=50 ns available on the board. When a single channel is used, the maximum count rate at Δt=50 ns was ∼350 kHz. With two channels we obtained ∼80 kHz at Δt=50 ns and ∼120 kHz at Δt=100 ns. Pulse streams with Gaussian statistics and in the presence of shot noise were simulated and measured with a commercial hardware correlator. Photodetector defects, such as the presence of afterpulses, were also simulated and their elimination by cross correlation techniques was checked. The simulator works also as a general purpose pulse pattern generator (PPG). Compared with commercial PPGs, our simulator is slower, but permits a continuous output of the pulse stream (not allowed in PPGs). At the same time it offers many other nontrivial advantages related to its flexibility, relatively low cost, and easy adaptability to future technology developments. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]