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Energy‐dispersive Laue diffraction (EDLD) is a powerful method to obtain position‐resolved texture information in inhomogeneous biological samples without the need for sample rotation. This study employs EDLD texture scanning to investigate the impact of two salivary peptides, statherin (STN) and histatin‐1 (HTN) 21 N‐terminal peptides (STN21 and HTN21), on the crystallographic structure of dental enamel. These proteins are known to play crucial roles in dental caries progression. Three healthy incisors were randomly assigned to three groups: artificially demineralized, demineralized after HTN21 peptide pre‐treatment and demineralized after STN21 peptide pre‐treatment. To understand the micro‐scale structure of the enamel, each specimen was scanned from the enamel surface to a depth of 250 µm using microbeam EDLD. Via the use of a white beam and a pixelated detector, where each pixel functions as a spectrometer, pole figures were obtained in a single exposure at each measurement point. The results revealed distinct orientations of hydroxyapatite crystallites and notable texture variation in the peptide‐treated demineralized samples compared with the demineralized control. Specifically, the peptide‐treated demineralized samples exhibited up to three orientation populations, in contrast to the demineralized control which displayed only a single orientation population. The texture index of the demineralized control (2.00 ± 0.21) was found to be lower than that of either the STN21 (2.32 ± 0.20) or the HTN21 (2.90 ± 0.46) treated samples. Hence, texture scanning with EDLD gives new insights into dental enamel crystallite orientation and links the present understanding of enamel demineralization to the underlying crystalline texture. For the first time, the feasibility of EDLD texture measurements for quantitative texture evaluation in demineralized dental enamel samples is demonstrated. [ABSTRACT FROM AUTHOR]

Light sensors are widely used to monitor light intensities, for instance in medical applications, in agriculture or for conservation of art. Most of these sensors are electronic devices that record continuously but applications that only require information of integrated intensities, measured over a long time, could greatly benefit from an integrating dosimeter that does not require a power supply. In this work a wireless and quantitative light dosimeter is presented based on SrAl2O4:Eu2+,Sm3+, a phosphor that exhibits stable energy storage upon exposure to blue and ultraviolet light. It is shown that a forward electron transfer from europium to samarium can be induced under illumination with blue or ultraviolet light while the reverse electron transfer can be achieved by illuminating the phosphors with green to infrared light. This reverse transfer is accomplished through excitation of the divalent samarium and results in bright, green optically stimulated luminescence. The stable energy storage, in combination with the possibility for optical read‐out, makes SrAl2O4:Eu2+,Sm3+ ideally suited to be used as an integrating light dosimeter for monochromatic to broadband light, from the ultraviolet to the near infrared. To demonstrate this, a proof of concept dosimeter was developed in which this phosphor was successfully used to measure average daylight intensities. [ABSTRACT FROM AUTHOR]

Friedreich's ataxia (FRDA) is a neurodegenerative disease characterized by an increase in intracytoplasmic iron concentration. Here the nanoscale iron distribution within single fibroblasts from FRDA patients was investigated using synchrotron‐radiation‐based nanoscopic X‐ray fluorescence and X‐ray in‐line holography at the ID16A nano‐imaging beamline of the ESRF. This unique probe was deployed to uncover the iron cellular two‐dimensional architecture of freeze‐dried FRDA fibroblasts. An unsurpassed absolute detection capability of 180 iron atoms within a 30 nm × 50 nm nanoscopic X‐ray beam footprint was obtained using state‐of‐the‐art X‐ray focusing optics and a large‐solid‐angle detection system. Various micrometre‐sized iron‐rich organelles could be revealed for the first time, tentatively identified as endoplasmic reticulum, mitochondria and lysosomes. Also a multitude of nanoscopic iron hot‐spots were observed in the cytosol, interpreted as chaperoned iron within the fibroblast's labile iron pool. These observations enable new hypotheses on the storage and trafficking of iron in the cell and ultimately to a better understanding of iron‐storage diseases such as Friedreich's ataxia. [ABSTRACT FROM AUTHOR]

Multilayer monochromator devices are commonly used at (imaging) beamlines of synchrotron facilities to shape the X‐ray beam to relatively small bandwidth and high intensity. However, stripe artefacts are often observed and can deteriorate the image quality. Although the intensity distribution of these artefacts has been described in the literature, their spectral distribution is currently unknown. To assess the spatio‐spectral properties of the monochromated X‐ray beam, the direct beam has been measured for the first time using a hyperspectral X‐ray detector. The results show a large number of spectral features with different spatial distributions for a [Ru, B4C] strip monochromator, associated primarily with the higher‐order harmonics of the undulator and monochromator. It is found that their relative contributions are sufficiently low to avoid an influence on the imaging data. The [V, B4C] strip suppresses these high‐order harmonics even more than the former, yet at the cost of reduced efficiency. [ABSTRACT FROM AUTHOR]

At the French synchrotron facility SOLEIL, a new X‐ray imaging facility PUMA (Photons Utilisés pour les Matériaux Anciens) has been made available to scientific communities studying materials from cultural heritage. This new instrument aims to achieve 2D and 3D imaging with microscopic resolution, applying different analytical techniques including X‐ray fluorescence spectroscopy (XRF), X‐ray absorption spectroscopy (XAS), X‐ray diffraction and phase‐contrast imaging. In order to discover its capabilities a detailed analytical characterization of this beamline as an analytical and imaging tool is deemed necessary. In this work, (confocal) XRF and XAS analyses are demonstrated using the Seymchan pallasite meteorite and an Antarctic unmelted micrometeorite as case studies. The obtained spatial resolution (2 µm × 3 µm) and sensitivity (detection limits <10 p.p.m. for 1 s acquisition at 18 keV) show that PUMA is a competitive state‐of‐the‐art beamline, providing several high‐profile and high‐in‐demand analytical methods while maintaining applicability towards a wide range of heritage‐oriented sciences. [ABSTRACT FROM AUTHOR]

This study aims at analyzing the mineralogical, chemical, and structural characteristics of flint raw material used for the production of prehistoric stone tools in NW Belgium. Understanding these characteristics is important to recognize their value for tool making and even tool use during prehistory. Due to its formation process, flint is defined by a wide variety of internal structures, chemical variations, and impurities. Moreover, alteration processes cause additional chemical and structural changes complicating the study of this material. Archaeological artifacts often display alteration features, mostly expressed as patination or burning, leading them to be regularly discarded from the functional analysis of lithic tools. By not incorporating these artifacts, our understanding of the investigated assemblage is biased. It is therefore important to investigate the influence of flint characteristics on its weathering behavior, and the impact of preservation of prehistoric use‐wear traces on flint artifacts. The characteristics of flint raw material and natural patination were studied using a combination of different techniques, such as macroscopic analysis, optical microscopy, X‐ray fluorescence, and high‐resolution X‐ray computed tomography. This resulted in a detailed description and distinction of the different flint variants used on prehistoric sites in NW Belgium and a good understanding of patination. [ABSTRACT FROM AUTHOR]

Abstract: In this work we investigate a mesoporous silica (MS) decorated with dipyridyl‐pyridazine (dppz) ligands and further grafted with a mixture of Eu3+/Tb3+ ions (28.45%:71.55%), which was investigated as a potential thermometer in the 10–360 K temperature range. The MS material was prepared employing a hetero Diels–Alder reaction: 3,6‐di(2‐pyridyl)‐1,2,4,5‐tetrazine was reacted with the double bonds of vinyl‐silica (vSilica) followed by an oxidation procedure. We explore using the dppz‐vSilica material to obtain visible emitting luminescent materials and for obtaining a luminescent thermometer when grafted with Eu3+/Tb3+ ions. For the dppz‐vSilica@Eu,Tb material absolute sensitivity Sa of 0.011 K−1 (210 K) and relative sensitivity Sr of 1.32 %K−1 (260 K) were calculated showing good sensing capability of the material. Upon temperature change from 10 K to 360 K the emission color of the material changed gradually from yellow to red. [ABSTRACT FROM AUTHOR]

Abstract: This work presents a novel anticounterfeiting strategy based on a material changing its emission color in response to a change in the excitation sources—where a single ultraviolet (UV) or near‐infrared (NIR) light source are employed or simultaneously using two excitation sources (xenon lamp and NIR laser). Following this approach, various combinations of lanthanide (Ln3+)‐doped LiLuF4/LiYF4 core/shell nanoparticles are prepared, providing a promising route to design flexible nanomaterials, as well as already a small library of luminescent materials, which change color when varying the excitation source (UV, NIR or both UV and NIR). Aside from excitation source‐dependent color change, these materials additionally show excitation‐source power‐dependent color change. This work exploits the possibility of developing a new class of multimode anticounterfeit nanomaterials, with excellent performance, which would be almost impossible to mimic or replicate, providing a very high level of security. [ABSTRACT FROM AUTHOR]

To improve the ecological relevance of environmental risk assessment, an improved understanding is needed of 1) the influence of environmental conditions on the toxicity of pollutants, and 2) the effect of these factors in combination with possible interpopulation variability. The influences of salinity and dissolved organic carbon (DOC) on the accumulation and effect of copper (Cu) to settled mussels were investigated with mussels from a North Sea and a Baltic Sea population. We found that both populations were equally Cu-sensitive, even though the Baltic Sea population lives in suboptimal conditions. Baltic Sea mussels, however, accumulated more Cu. This suggests that these populations may have different ways of coping with excess Cu. The influence of salinity on Cu toxicity to settled mussels was limited for both populations. An increase in DOC did not decrease the Cu accumulation or effect in either population. This suggests that DOC-Cu complexes are bioavailable for settled mussels. These findings are in contrast with previous research which indicated that DOC decreased the toxicity and accumulation of Cu in the D-larvae life stage. As a consequence, the mussel larval stage is not the most Cu-sensitive life stage at high DOC concentrations. Furthermore, a DOC correction factor for Cu toxicity cannot be used for settled mussels. This should be accounted for in future marine Cu environmental risk assessment. Environ Toxicol Chem 2017;36:2074-2082. © 2017 SETAC [ABSTRACT FROM AUTHOR]

Hybrid materials displaying multistage security behavior, where a single material shows both wavelength- and temperature-dependent luminescence properties, are reported. The materials consist of mixed-lanthanide β-diketonate complexes grafted into the pores of a nanosized 2,2′-bipyridine-5,5′-dicarboxylate-acid MOF. A very specific choice of lanthanides and their ratios, as well as β-diketonate ligand, is crucial for obtaining the desired properties. The wavelength-dependent luminescence properties of the materials are very well matched with the excitation wavelengths of a standard UV lamp, and a clearly visible change in luminescence is observed in a narrow temperature range (slightly below and above room temperature), proving them to be excellent materials for use in anti-counterfeit technologies, which would be almost impossible to mimic. [ABSTRACT FROM AUTHOR]

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Conventional analysis of the preferred orientation of crystallites (crystallographic texture) involves X-ray diffraction with area detectors and 2D data output. True 3D, spatially resolved information requires sample rotation in the beam, thus changing the probed volume, which introduces signal smearing and precludes the scanning of complex structures. This obstacle has been overcome by energy-dispersive Laue diffraction. A method has been devised to reach a large portion of reciprocal space and translate the X-ray photon energy into the missing third dimension of space. Carbon fibers and lobster exoskeleton as examples of biomineralized tissue have been analyzed. The major potential of this method lies in its 'one-shot' nature and the direct 3D information requiring no previous knowledge of the sample. It allows the texture of large samples with complex substructures to be scanned and opens up the conceptual possibility of following texture changes in situ, for example, during crystallization. [ABSTRACT FROM AUTHOR]

Recently, a radically new synchrotron radiation-based elemental imaging approach for the analysis of biological model organisms and single cells in their natural in vivo state was introduced. The methodology combines optical tweezers (OT) technology for non-contact laser-based sample manipulation with synchrotron radiation confocal X-ray fluorescence (XRF) microimaging for the first time at ESRF-ID13. The optical manipulation possibilities and limitations of biological model organisms, the OT setup developments for XRF imaging and the confocal XRF-related challenges are reported. In general, the applicability of the OT-based setup is extended with the aim of introducing the OT XRF methodology in all research fields where highly sensitive in vivo multi-elemental analysis is of relevance at the (sub)micrometre spatial resolution level. [ABSTRACT FROM AUTHOR]

Predicting copper (Cu) toxicity in marine and estuarine environments is challenging because of the influence of anions on Cu speciation, competition between Cu2+ and other cations at the biotic ligand and the effect of salinity on the physiology of the organism. In the present study the combined effect of salinity and dissolved organic carbon (DOC) on Cu toxicity to larvae of Mytilus galloprovincialis was assessed. Two statistical models were developed and used to elucidate the relationship between Cu toxicity, salinity, and DOC. All models based on dissolved Cu indicate a decrease in Cu toxicity with increasing DOC concentrations, which can partly be explained by complexation of Cu2+ ions with DOC. These models also indicate an increase in Cu toxicity (modeled with dissolved Cu or Cu2+ activity) with increasing salinity, suggesting a salinity-induced alteration in the physiology of the mussel larvae. When based on Cu body burdens, neither of the models indicates an effect of salinity or DOC. This shows that the Cu body burden is a more constant predictor of Cu toxicity, regardless of the water chemistry influencing Cu speciation or competition and possible physiological alterations or changes in Cu speciation or competition. Environ Toxicol Chem 2015;34:1330-1336. © 2015 SETAC [ABSTRACT FROM AUTHOR]

This article tests a model predicting minority language television consumption. We examine how four media gratifications (diversion, ethnolinguistic identity, surveillance, parasocial companionship) mediate the relationship between ethnolinguistic identification and choice of ingroup language television viewing. The study is performed among (minority) Hungarian speakers in Transylvania, Romania. Self-report questionnaire data from 401 Hungarian-speaking high school students in Csíkszereda/Miercurea Ciuc (a majority Hungarian locale) and Brassó/Brașov (a minority Hungarian locale) allowed us to compare high and low local vitality conditions. Analysis indicates that diversion (entertainment) and ethnolinguistic identity gratifications for watching ingroup language television are the strongest mediators of the influence of identification on ingroup language television use. We examined four moderators of these indirect effects (objective vitality, subjective vitality, intergroup contact, and intragroup contact). The moderators revealed a number of rather complex effects which are discussed with regard to the local intergroup context and broader issues of media and intergroup relations. [ABSTRACT FROM AUTHOR]

Using synchrotron-based X-ray diffraction measurements, we identified crystalline material in two particles of extraterrestrial origin extracted from the Stardust Interstellar Dust Collector. The first particle, I1047,1,34 (Hylabrook), consisted of a mosaiced olivine grain approximately 1 µm in size with internal strain fields up to 0.3%. The unit cell dimensions were a = 4.85 ± 0.08 Å, b = 10.34 ± 0.16 Å, c = 6.08 ± 0.13 Å (2σ). The second particle, I1043,1,30 (Orion), contained an olivine grain ≈ 2 µm in length and >500 nm in width. It was polycrystalline with both mosaiced domains varying over ≈ 20 [ABSTRACT FROM AUTHOR]

Here, we report analyses by synchrotron X-ray fluorescence microscopy of the elemental composition of eight candidate impact features extracted from the Stardust Interstellar Dust Collector (SIDC). Six of the features were unambiguous tracks, and two were crater-like features. Five of the tracks are so-called 'midnight' tracks-that is, they had trajectories consistent with an origin either in the interstellar dust stream or as secondaries from impacts on the Sample Return Capsule (SRC). In a companion paper reporting synchrotron X-ray diffraction analyses of ISPE candidates, we show that two of these particles contain natural crystalline materials: the terminal particle of track 30 contains olivine and spinel, and the terminal particle of track 34 contains olivine. Here, we show that the terminal particle of track 30, Orion, shows elemental abundances, normalized to Fe, that are close to CI values, and a complex, fine-grained structure. The terminal particle of track 34, Hylabrook, shows abundances that deviate strongly from CI, but shows little fine structure and is nearly homogenous. The terminal particles of other midnight tracks, 29 and 37, had heavy element abundances below detection threshold. A third, track 28, showed a composition inconsistent with an extraterrestrial origin, but also inconsistent with known spacecraft materials. A sixth track, with a trajectory consistent with secondary ejecta from an impact on one of the spacecraft solar panels, contains abundant Ce and Zn. This is consistent with the known composition of the glass covering the solar panel. Neither crater-like feature is likely to be associated with extraterrestrial materials. We also analyzed blank aerogel samples to characterize background and variability between aerogel tiles. We found significant differences in contamination levels and compositions, emphasizing the need for local background subtraction for accurate quantification. [ABSTRACT FROM AUTHOR]

The article presents a study that discusses the use of diamond-anvil cells (DACs) aimed at improving micro-XRF and XAFS experiments. It mentions that a confocal set-up has been established to enhance the quality of the fluorescence and XAFS spectra. It affirms that the result shows that the set-up suppresses signal from outside the sample chamber and creates excitation of fluorescence from the body of the DAC.

A focusing system based on a polycapillary half-lens optic has been successfully tested for transmission and fluorescence μ-X-ray absorption spectroscopy at a third-generation bending-magnet beamline equipped with a non-fixed-exit Si(111) monochromator. The vertical positional variations of the X-ray beam owing to the use of a non-fixed-exit monochromator were shown to pose only a limited problem by using the polycapillary optic. The expected height variation for an EXAFS scan around the Fe K-edge is approximately 200 μm on the lens input side and this was reduced to ~1 μm for the focused beam. Beam sizes (FWHM) of 12-16 μm, transmission efficiencies of 25-45% and intensity gain factors, compared with the non-focused beam, of about 2000 were obtained in the 7-14 keV energy range for an incoming beam of 0.5 × 2 mm (vertical × horizontal). As a practical application, an As K-edge μ-XANES study of cucumber root and hypocotyl was performed to determine the As oxidation state in the different plant parts and to identify a possible metabolic conversion by the plant. [ABSTRACT FROM AUTHOR]

In article number 1700258, Anna M. Kaczmarek, Rik Van Deun, and co‐workers describe hybrid materials displaying a multi‐stage security behavior, where a single material shows both wavelength‐ and temperature‐dependent luminescence properties. The materials consist of mixed lanthanide β‐diketonate complexes grafted into the pores of a nano‐sized metal organic framework (MOF), which show “chameleon” behavior. [ABSTRACT FROM AUTHOR]

Kristallographische Textur. H. C. Lichtenegger et al. beschreiben in der Zuschrift auf S. 12376 ff. eine Methode zur Bestimmung der kristallographischen Textur auf der Grundlage der energiedispersiven Laue ‐ Beugung. Ohne Drehung der Probe können 3D ‐ Informationen erhalten werden. [ABSTRACT FROM AUTHOR]

The cover page of the journal "Angewandte Chemie International Edition" is presented, which offers information on the article "Photon Energy Becomes the Third Dimension in Crystallographic Texture Analysis," by Harald Rennhofer and others.