The development and application of imaging EXAFS spectromicroscopy

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Scanning small-angle X-ray scattering (sSAXS) has found multiple applications as a technique to probe the nanostructure in soft tissues and pathologies thereof. However, fresh tissue is fragile and prone to the quick onset of decomposition and autolysis. It lacks the firmness required for uniform and thin sectioning, resulting in the loss of 2D resolution offered by focused X-ray beams, because the signal would be integrated through thick and/or irregular sections. Tissue processing, that includes fixation

Active galactic nuclei (AGN) are an important phase in galaxy evolution. However, they can be difficult to identify due to their varied observational signatures. Furthermore, to understand the impact of an AGN on its host galaxy, it is important to quantify the strength of the AGN with respect to the host galaxy. We developed a deep learning (DL) model to identify AGN in imaging data by deriving the contribution of the central point source. The model was trained with Euclidised mock galaxy images in which w

Advancements in analyzing iron archaeological artifacts are helpful in many applications, i.e., elucidating corrosion phenomena experienced by nuclear waste repositories and lifetime prediction of still-buried objects, such as pipelines. This paper investigates the corrosion state of iron-based archaeological objects through bimodal neutron and X-ray computed tomography, SEM-EDX analysis, and Raman spectroscopy. The nail BdC2, excavated from the archaeological site Bois de Châtel in Switzerland, is used as

Photochemical aging in secondary organic aerosol (SOA) particles alters their chemical composition and affects their adverse health effects. However, there is limited mechanistic insight on the role of transition metals in photochemical SOA aging and the evolution of the oxidative potential through their effect on radical chemistry. Here, we investigated the influence of copper (Cu) on the photochemical aging of iron (Fe) containing SOA in single particles using scanning transmission X-ray microscope measur

Laser Powder Bed Fusion (LPBF) is a promising metal additive manufacturing (AM) technology that enables high-precision fabrication of high-performance parts with unprecedented design flexibility. However, its widespread adoption remains hindered by the occurrence of various defects, which significantly degrade the mechanical properties and reproducibility of fabricated parts. These defects are inherently linked to the complex and dynamic nature of melt pool behavior, governed by a combination of laser-mater

Recent advances in generative models for nucleotide sequences have shown promise, but their practical utility remains limited. In this study, we explore DNA as a complex functional representation of evolutionary processes and assess the ability of transformer-based models to capture this complexity. Through experiments with both synthetic and real DNA sequences, we demonstrate that current transformer architectures, particularly auto-regressive models relying on next-token prediction, struggle to effectivel

We present here the design of a linear octupole ion trap, suitable for collisional cryogenic cooling and spectroscopy of large ions. The performance of this trap has been assessed using ultraviolet (UV) photofragmentation spectroscopy of protonated dipeptides. At the trap temperature of 6.1 K, the vibrational temperature of the ions reaches 9.1 K, although their estimated translational temperature is similar to 150 K. This observation suggests that, despite the significant translational heating by radio-fre

A new type of Nafion/Fe structured membrane ensuring faster kinetics, higher efficiency, and mechanical properties has been prepared and will be compared in its performance with the Fe-exchanged commercial Dupont 117 Nafion/Fe membrane during the abatement of model organic compounds. During the casting of the laboratory Nafion sample, the iron ions were introduced directly into the Nafion oligomer solution. This novel laboratory Nafion/Fe was tested as an immobilized catalyst in the degradation of several t

The effect of gamma radiation on the physical-chemical properties of sodium alginate Algimar has been investigated. Dilution viscometry, densitometry, and FTIR spectroscopy served to identify modifications. Decreasing intrinsic viscosities clearly revealed chain cleavage for both solid alginate and alginate in aqueous solution. The invariance of the partial specific volume and infrared results indicate that chain degradation occurs without significant change of the chemical structure. The obtained results h

The absorption and emission spectra of the 3P1-1S0 transition of a Hg atom embedded in solid Ar were simulated using the mol. dynamics with quantum transitions algorithm to consider the nonadiabatic transitions between the three adiabatic states. The simulations also take into account the zero-point fluctuations at the exptl. temp. of 4 K using a temp. correction that mimics them. The simulated spectra show fair agreement with the exptl. data for the abs. energies and very good agreement for the absorption-

The description at at. level of protein folding is an ambitious goal in biophysics, particularly because of the difficulty in obtaining structural information on unfolded states. Computer simulations can contribute in achieving this goal. Here we report the results of a 10-ns comparative simulation on bovine RNase A and its S-protein, obtained by removal from the native mol. of the first 20 residues, the so-called S-peptide. The at. trajectories have been analyzed by std. procedures and by applying concepts

We present a tunable interference filter for infrared and visible light that scans the desired part of the optical spectrum within milliseconds. A single pixel detector measures serially the intensity at selected wavelengths. This concept: avoids expensive linear detectors as used for grating spectrometers. The tunable optical interference filter is fabricated by a new porous silicon batch technology using only two photolithography steps. The refractive index of this filter microplate is gradually modulated

Comprehensive in-situ bioreactor monitoring and control based on a midinfrared spectroscopic sensor system M. Rhiel1, C. Cannizzaro1, S. Valentinotti2, I. Marison1, U. von Stockar1 1 Institute of Chemical Engineering, 2Institute of Automatic Control Swiss Federal Institute of Technology (EPFL), CH- 1015 Lausanne, Switzerland Abstract A mid-infrared spectroscopic sensor system consisting of a spectrometer, a single attenuated total reflectance (ATR) probe immersed in the bioreactor, and a software package fo

The structural phases observed in LiKSO4 crystals due to thermotropic transitions have been studied for more than a century. Nowadays many different phases are referenced, but some of the results are still controversial. Structural studies by single-crystal X-ray diffraction from room temperature to 803 K are presented here. Phase II (708 < T < 943 K) is extensively discussed on the basis of ordered and disordered models, using harmonic and anharmonic atomic displacements, and considering a twinned crystal

Infrared (IR) absorption spectroscopy and mass spectrometry have been simultaneously applied to dusty radiofrequency (RF) plasmas in methane, acetylene and ethylene. The combination of IR absorption spectroscopy and mass spectrometry allows the chemical composition and structure of the most relevant plasma-produced neutral species, the ionic plasma composition and the chemical composition of the nanometer-sized particles to be precisely identified. The production of acetylenic compounds (C2Hx) seems to be a

Differently prepared surfaces of quasicrystalline i-Al-Pd-Mn are analyzed using angle-resolved photoemission in the X-ray and ultraviolet range of photon energies. Depending on the preparation, we find both surfaces with crystalline structure and metallic character, and surfaces with quasicrystalline structural fingerprints and a suppressed density of states at the Fermi level, compatible with a pseudogap.

The smaller isoform of the GABA-synthesizing enzyme, glutamic acid decarboxylase 65 (GAD65), is unusually susceptible to becoming a target of autoimmunity affecting its major sites of expression, GABA-ergic neurons and pancreatic β-cells. In contrast, a highly homologous isoform, GAD67, is not an autoantigen. We used homolog-scanning mutagenesis to identify GAD65-specific amino acid residues which form autoreactive B-cell epitopes in this molecule. Detailed mapping of 13 conformational epitopes, recognized

In situ Fourier transform infrared absorption spectroscopy has been used to study the composition of particles formed and suspended in radio-frequency discharges of silane-oxygen-argon gas mixtures. The silane gas constumption was observed by infrared absorption. The stoichiometry of the produced particles depends on the silane flow rate and was compared with commercial colloidal silica. A small proportion of silane gas produces nanometric stoichiometric particles whereas a large proportion produces larger

In the process of developing tools for cavitation erosion prediction of prototypes from mode) tests, 4 on board aggressiveness evaluation methods were tested on a severely eroded blade of a 266 MW Francis turbine. These are pressure, pit counting, DECER electrochemical and vibration measurements. All methods provided coherent results on the blade mounted measurements. The test program provided understanding of the heterogeneous erosion distribution of the prototype blades and quantitative data for compariso

Pb2CoWO6 in its incommensurate phase (230 less than or equal to T less than or equal to 300 K) invariably exhibits orientational domains. Such a polydomain state has been investigated by means of X-ray diffraction at 283 K. Assuming the modulation to be one-dimensional, we have identified the orientations of four domains. In view of the pseudosymmetry of this phase, many refinements of a purely displacive modulation had to be performed in order to establish the best suited unit cell and superspace group. Tw

The development and application of imaging EXAFS spectromicroscopy

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Effect of soft tissue sample preparation techniques for scanning small-angle X-ray scattering experiments

Euclid Quick Data Release (Q1): XVIII. First Euclid statistical study of the active galactic nuclei contribution fraction

Future from the Past: Long-Term Corrosion of Iron Analyzed Using Bimodal Neutron and X-ray CT

Copper Accelerates Photochemically Induced Radical Chemistry of Iron-containing Secondary Organic Aerosol (soa)

Uncovering melt pool dynamics and laser absorption mechanisms in laser powder bed fusion through in-situ experiments and high-fidelity multiphysics simulations

Life as a Function: Why Transformer Architectures Struggle to Gain Genome-Level Foundational Capabilities

Cryogenically cooled octupole ion trap for spectroscopy of biomolecular ions

Synthesis, Testing, and Characterization of a Novel Nafion Membrane with Superior Performance in Photoassisted Immobilized Fenton Catalysis

Physical-chemical Modification of Sodium Alginate ALGIMAR by Irradiation

Nonadiabatic Dynamics of Excited Hg(3P1) in Ar Matrixes

Dynamics of RNase-A and S-protein: A molecular dynamics simulation of the transition toward a folding intermediate

Low cost microspectrometer

Comprehensive in-situ Bioreactor Monitoring and Control Based on a Mid-Infrared Spectroscopic Sensor System

Analysis of LiKSO4 crystals in the temperature range from 573 to 943 K

Investigations of CH4, C2H2 and C2H4 dusty RF plasmas by means of FTIR absorption spectroscopy and mass spectrometry

Quasicrystalline nature of quasicrystal surfaces: A photoemission study

High-resolution autoreactive epitope mapping and structural modeling of the 65 kDa form of human glutamic acid decarboxylase

Silicon oxide particle formation in RF plasmas investigated by infrared absorption spectroscopy and mass spectrometry

Cavitation Erosion Prediction on Francis Turbines Part 1 : Measurements on the Prototype

X-Ray Study of and Structural Approach to the Incommensurate Perovskite Pb2CoWO6