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The origin of micrometeorites (MMs) from asteroids and comets is well-established, but the relative contribution from these two classes remains poorly resolved. Likewise, determining the precise origin of individual MMs is an open challenge. Here, cosmic-ray exposure ages are used to resolve the spatial origins of 12 MMs collected from urban areas and Antarctica. Their 26Al and 10Be concentration, produced during cosmic-ray irradiation in space, were measured by accelerator mass spectrometry. These data are compared to results from a model simulating the transport and irradiation of the MM precursors in space. This model, for the first time, considers a variety of orbits, precursor particle sizes, compositions and densities and incorporates non-isotropic solar and galactic cosmic-ray flux profiles, depth-dependent production rates, as well as spherical evaporation during atmospheric entry. While the origin for six MMs remains ambiguous, two MMs show a preferential tendency towards an origin in the Inner Solar System (Near Earth Objects to the Asteroid Belt) and four towards an origin in the Outer Solar System (Jupiter Family Comets to the Kuiper Belt). These findings challenge the notion that dust originating from the Outer Solar System is unlikely to survive long-term transport and delivery to the terrestrial planets. This article is part of the theme issue 'Dust in the Solar System and beyond'. [ABSTRACT FROM AUTHOR]

Pitted impact deposits on Vesta show higher reflectance and pyroxene absorption band strengths compared to their immediate surroundings and other typical Vestan materials. We investigated whether heating to different temperatures for different durations of Vestan regolith analog materials can reproduce these spectral characteristics using mixtures of HEDs, the carbonaceous chondrite Murchison, and terrestrial analogs. We find no consistent spectral trend due merely to temperature increases, but observed that the interiors of many heated samples show both higher reflectance and pyroxene band I strength than their heated surfaces. With electron probe microanalysis, we additionally observe the formation of hematite, which could account for the higher reflectance. The presence of hematite indicates oxidation occurring in the sample interiors. In combination with heat, this might cause the increase of pyroxene band strengths through migration of iron cations. The effect grows larger with increasing temperature and duration, although temperature appears to play the more dominant role. A higher proportion of Murchison or the terrestrial carbonaceous chondrite analog within our mixtures also appears to facilitate the onset of oxidation. Our observations suggest that both the introduction of exogenic material on Vesta as well as the heating from impacts were necessary to enable the process (possibly oxidation) causing the observed spectral changes. [ABSTRACT FROM AUTHOR]

Experimental studies of the glassy slowdown in molecular liquids indicate that the high-temperature activation energy E∞ of glass-forming liquids is directly related to their glass transition temperature Tg. To further investigate such a possible relation between high- and low-temperature dynamics in glass-forming liquids, we analyze the glassy dynamics of binary mixtures using molecular dynamics simulations. We consider a binary mixture of charged Lennard-Jones particles and vary the partial charges of the particles and, thus, the high-temperature activation energy and the glass transition temperature of the system. Based on previous results, we introduce a phenomenological model describing relaxation times over the whole temperature regime from high temperatures to temperatures well inside the supercooled regime. By investigating the dynamics of both particle species on molecular and diffusive length scales along isochoric and isobaric pathways, we find a quadratic charge dependence of both E∞ and Tg, resulting in an approximately constant ratio of both quantities independent of the underlying observable, the thermodynamic ensemble, and the particle species, and this result is robust against the actual definition of Tg. This generic relation between the activation energy and the glass transition temperature indicates that high-temperature dynamics and the glassy slowdown are related phenomena, and the knowledge of E∞ may allow us to approximately predict Tg. [ABSTRACT FROM AUTHOR]

We report the recovery and characterization of a new urban micrometeorite collection derived from the rooftop of an industrial building in Germany. We identified 315 micrometeorites (diameter: 55–515 µm, size peak: ˜150 µm, size distribution slope exponent: −2.62). They are predominantly S‐type cosmic spherules (97.2%) but also two G‐type spherules (0.6%), an unmelted coarse‐grained single‐mineral micrometeorite, and eight scoriaceous particles (2.5%) or particles transitional between scoriaceous micrometeorites and porphyritic spherules. Their analysis details how the magnetite rim on partially melted micrometeorites is progressively diluted as the melt fraction increases during heating. At least 10 micrometeorites contain platinum group nuggets (PGNs). They have chondritic compositions but are depleted in volatile Pd. However, a single nugget preserves chondritic Pd concentrations. We suggest that an Fe‐Ni‐S bead originally containing the PGN escaped its host cavity and wet the particle exterior, creating an Fe‐rich melt that protected the nugget from evaporation. This melt layer oxidized forming magnetite—indicating that wetting events can affect the texture and composition of micrometeorites. Utilizing the well‐constrained surface area (8400 m2) and rooftop age (21 yr), we attempted the first global mass flux estimate based on urban micrometeorite data. This produced anomalously low values (13.4 t yr–1), even when correcting for losses due to sample processing (<89.7 t yr–1). Our value is approximately two orders of magnitude lower than previous estimates, indicating that >99% of particles are missing, having been lost via drainage and cleaning. Rooftop collection sites have limited potential for mass flux calculations unless problems of loss can be resolved. However, urban micrometeorite collections have other advantages, notably exceptionally well‐preserved particles with extremely young terrestrial ages and the ability to extract many micrometeorites from accessible sites. Urban micrometeorites should be considered complementary to Antarctic and deep‐sea collections with potential for citizen science and educational exploitation. [ABSTRACT FROM AUTHOR]

Drill core UNAM‐7, obtained 126 km from the center of the Chicxulub impact structure, outside the crater rim, contains a sequence of 126.2 m suevitic, silicate melt‐rich breccia on top of a silicate melt‐poor breccia with anhydrite megablocks. Total reflection X‐ray fluorescence analysis of altered silicate melt particles of the suevitic breccia shows high concentrations of Br, Sr, Cl, and Cu, which may indicate hydrothermal reaction with sea water. Scanning electron microscopy and energy‐dispersive spectrometry reveal recrystallization of silicate components during annealing by superheated impact melt. At anhydrite clasts, recrystallization is represented by a sequence of comparatively large columnar, euhedral to subhedral anhydrite grains and smaller, polygonal to interlobate grains that progressively annealed deformation features. The presence of voids in anhydrite grains indicates SOx gas release during anhydrite decomposition. The silicate melt‐poor breccia contains carbonate and sulfate particles cemented in a microcrystalline matrix. The matrix is dominated by anhydrite, dolomite, and calcite, with minor celestine and feldspars. Calcite‐dominated inclusions in silicate melt with flow textures between recrystallized anhydrite and silicate melt suggest a former liquid state of these components. Vesicular and spherulitic calcite particles may indicate quenching of carbonate melts in the atmosphere at high cooling rates, and partial decomposition during decompression at postshock conditions. Dolomite particles with a recrystallization sequence of interlobate, polygonal, subhedral to euhedral microstructures may have been formed at a low cooling rate. We conclude that UNAM‐7 provides evidence for solid‐state recrystallization or melting and dissociation of sulfates during the Chicxulub impact event. The lack of anhydrite in the K‐Pg ejecta deposits and rare presence of anhydrite in crater suevites may indicate that sulfates were completely dissociated at high temperature (T > 1465 °C)—whereas ejecta deposited near the outer crater rim experienced postshock conditions that were less effective at dissociation. [ABSTRACT FROM AUTHOR]

This study introduces an experimental approach using direct laser irradiation to simulate the virtually instantaneous melting of target rocks during meteorite impacts. We aim at investigating the melting and mixing processes of projectile (iron meteorite; steel) and target material (sandstone) under idealized conditions. The laser experiments ( LE) were able to produce features very similar to those of impactites from meteorite craters and cratering experiments, i.e., formation of lechatelierite, partial to complete melting of sandstone, and injection of projectile droplets into target melts. The target and projectile melts have experienced significant chemical modifications during interaction of these coexisting melts. Emulsion textures, observed within projectile-contaminated target melts, indicate phase separation of silicate melts with different chemical compositions during quenching. Reaction times of 0.6 to 1.4 s could be derived for element partitioning and phase-separation processes by measuring time-depended temperature profiles with a bolometric detector. Our LE allow (i) separate melting at high temperatures to constrain primary melt heterogeneities before mixing of projectile and target, (ii) quantification of element partitioning processes between coexisting projectile and target melts, (iii) determination of cooling rates, and (iv) estimation of reaction times. Moreover, we used a thermodynamic approach to calculate the entropy gain during laser melting. The entropy changes for laser-melting of sandstone and iron meteorite correspond to shock pressures and particle velocities produced during the impact of an iron projectile striking a quartz target at a minimum impact velocity of ~6 km s−1, inducing peak shock pressures of ~100 GPa in the target. [ABSTRACT FROM AUTHOR]

A 435 kg piece of the Mont Dieu iron meteorite ( MD) contains cm-sized silicate inclusions. Based on the concentration of Ni, Ga, Ge, and Ir (8.59 ± 0.32 wt%, 25.4 ± 0.9 ppm, 61 ± 2 ppm, 7.1 ± 0.4 ppm, respectively) in the metal host, this piece can be classified as a IIE nonmagmatic iron. The silicate inclusions possess a chondritic mineralogy and relict chondrules occur throughout the inclusions. Major element analysis, oxygen isotopic analysis (Δ17O = 0.71 ± 0.02‰), and mean Fa and Fs molar contents (Fa15.7 ± 0.4 and Fs14.4 ± 0.5) indicate that MD originated as an H chondrite. Because of strong similarities with Netschaëvo IIE, MD can be classified in the most primitive subgroup of the IIE sequence. 40Ar/39Ar ages of 4536 ± 59 Ma and 4494 ± 95 Ma obtained on pyroxene and plagioclase inclusions show that MD belongs to the old (~4.5 Ga) group of IIE iron meteorites and that it has not been perturbed by any subsequent heating event following its formation. The primitive character of MD sheds light on the nature of its formation process, its thermal history, and the evolution of its parent body. [ABSTRACT FROM AUTHOR]

High pressure homogenization is a well-established technique to achieve droplets in the submicron range. However, droplet breakup mechanisms are still not completely understood, since studies to characterize the flow are limited due to very small dimensions (typically several micrometers) and very large velocity ranges (from almost stagnant flow to 300 m/s and more). Furthermore, cavitation can occur resulting in multiphase flow. So far, experiments were performed only via integral measurements of, for example, the pressure drop or the droplet size distribution at the outlet. In the current study, this gap shall be closed using Particle Image Velocimetry measurements to analyze the flow field. In addition, an overall method, the characteristic correlation between the discharge coefficient ( C) and Re is used to distinguish between laminar, transitional and turbulent flow conditions at Reynolds numbers based on the channel width ( d = 200 µm) between 250 and 22,500. The investigated orifices of this study had different positions of the constriction: coaxial and next to the wall. For both orifices, the C measurement was applicable and showed different characteristic regions which can be associated with laminar, transitional and turbulent flow conditions. Mean velocity fields and fluctuations were measured quantitatively at the outlet and 50 diameters downstream using Micro Particle Image Velocimetry (µ-PIV) in an optically accessible orifice. Increased velocity fluctuations were found in the shear layers when the flow turns from laminar into unstable transitional conditions. The combination of both measurement techniques will help to optimize these systems for the future. [ABSTRACT FROM AUTHOR]

Introduction: Pallasite meteorites are stony-iron meteorites that predominantly consist of large, rounded to angular, forsteritic olivine grains embedded in a matrix of FeNi metal [1-3]. Pallasites provide rare insights into dunitic mantles of differentiated planetary bodies of the early solar system. However, the enigmatic juxtaposition of olivine in FeNi metal matrix has resulted in a still ongoing debate about whether they represent the core-mantle boundaries of differentiated planetesimals (e.g., [4]), are the result of a catastrophic impact that formed a 'pallasite planetesimal' (e.g., [5]), or whether they sample the shallow mantle of a planetesimal that suffered from non-catastrophic impact and injection of impactor-derived FeNi metal (e.g., [6,7]). Many pallasites such as Brenham, Brahin, Esquel, Imilac, Sericho, or Seymchan are large stones of hundreds of kilograms that provide substantial sample surfaces to be studied. The substantial sample size as well as the large grain size of typical olivine crystals, of kamacite and taenite domains of the matrix, and of volumetrically less abundant phases such as sulfides or chromites make pallasites ideally suited to test the potential of micro X-ray fluorescence (µXRF) analysis for correlated studies of large-scale textures and chemical compositions (cf. [8]). Micro X-ray fluorescence: μXRF analysis combines the advantages of conventional XRF analysis typically used to determine bulk compositions with the advantages of energy dispersive X-ray spectroscopy performed in scanning electron microscopy to determine chemical compositions of individual phases. State-of-the-art μXRF spectrometers can focus a high-energy X-ray beam to spot sizes of about 20 μm via a polycapillary lens, which allows non-destructive, spatially resolved, quantitative analysis of major, minor, and trace elements of atomic number ≥6 (carbon) from solids, powders, or liquids at tens of micrometers spatial resolution. Typical detection limits of μXRF are between 10 and 100 μg/g for most elements of interest in standard-free quantification based on a fundamental-parameter approach, but they may be lowered to <10 μg/g if suitable reference materials are used for a type calibration (e.g., [9]). Non-destructive characterization of pallasites by μXRF: As part of an ongoing project that tests the potential of μXRF analysis for non-destructive characterization, classification, and geochemical-mineralogical investigation of various meteorite types, we characterize pallasites in the meteorite collections of Museum für Naturkunde Berlin and Mineralogische Staatssammlung München by μXRF analysis using a Bruker M4 TORNADO PLUS μXRF spectrometer. To this end, we obtain element distribution maps over large sample areas (often >100 cm²) as shown in Fig. 1. We then obtain mode and compositions of individual phases, and possibly bulk chemical compositions, from the element distribution maps. Compositions of individual phases are furthermore obtained by μXRF spot measurements, from which also quantitative diffusion profiles spanning tens of millimeters in length can be obtained. To test accuracy and reproducibility of the obtained data and to establish typical detection limits of the method, we compare standard-free quantification against a type-calibrated μXRF quantification routine based on suitable reference materials (e.g., Springwater and San Carlos olivine; FeNi metal alloys; sulfides etc.). The different data acquisition approaches will be compared against results from independent techniques such as electron microprobe analysis or (laser-ablation) inductively coupled plasma mass spectrometry. [ABSTRACT FROM AUTHOR]

Definition and significance of suevite: By definition, suevite is a polymict impact breccia that contains impactderived melt particles in otherwise clastic material [1]. Glassy, lithic and mineral clasts are generally embedded in a particulate, clastic cum melt matrix. The presense of melt particles within polymict breccias is usually easy to identify, and therefore represents an important feature for the recognition of suevite as a proximal impactite in general, but specifically in the field. Suevite records various impact-related effects like rock comminution, different degrees of shock-metamorphism including melting, and the dynamics of crater formation. Furthermore, suevites, and specifically its lithic fragments, may record information on deeply buried lithologies. Suevite is a proximal impactite that occurs within or close to the impact structure. It is usually deposited in the upper part of the ejecta blanket, e.g. [2], [3], or impact melt sheet, e.g. [3], but it may also occur below the impact melt sheet, e.g. [4], [5], or as injections into the crater floor, e.g. [6]. Formation and emplacement models: Detailled studies in the recent years (including of the type example at Ries crater, Germany) have significantly improved our understanding of the formation and emplacement of suevite; however, many different hypotheses are still debated today. Some major hypotheses are (1) collapse of an ejecta plume, e.g. [7-9], (2) deposition via a density flow, e.g. [10], [11], (3) deposition from an impact melt flow, e.g. [12], (4) mixing between fragmented basement and impact melt during outflow, e.g. [4], [5], and (5) collapse of the post-impact phreatomagmatic plume(s) caused by fuel-coolant interaction (FCI) of an impact melt sheet with water or an aquifer, e.g. [13-15]. The co-existence of many different formation and emplacement models of suevite, some of which are controversial, may result from specific studies at different impact environments and conditions, the complexity of the formation process, the general lack of continuous outcrop of suevite deposits, and last not least, from some lack of understanding of the physical processes involved in the formation of such complex material in a highly dynamic environment. In this contribution to the Impact Cratering Workshop, the main existing genetic models of suevite formation will be reviewed and unresolved issues discussed, with some examples. [ABSTRACT FROM AUTHOR]

Introduction: Micrometeorites (MMs) are extraterrestrial dust particles mostly between ~10 µm and 2 mm across that survive atmospheric entry and arrive on Earth's surface [1,2]. Depending on their velocity, entry trajectory, and mass, MMs suffer variable degrees of flash heating. Especially the larger ones >100-200 µm undergo extensive melting and vaporization during atmospheric entry [3,4], which modifies their initial texture, mineralogy, and composition and results in formation of cosmic spherules [1,2]. Due to their small sizes and their significant modification during atmospheric entry, the mineralogical and compositional properties of MMs are unlikely to represent those of their parent bodies [1]. However, MMs may inform about the nature of their parent bodies if a link between certain groups of MMs can be established to certain types of parent bodies as well as their individual components and if the modification of MMs during atmospheric entry is understood. Here, we show by petrographic investigation of melt spherules produced by laser-induced flash heating of the H5 ordinary chondrite Hammadah al Hamra (HaH) 077 that most mineralogical and compositional properties of the most common types of micrometeorites can be produced from a single ordinary-chondrite sample, which has implications for the identification of potential parent bodies of MMs [5]. Materials and Methods: We used a continuous-wave infrared fiber laser to irradiate a piece of HaH 077 in air at 1 bar using methods described in [6]. Flash heating of HaH 077 produced massive, tens of millimeters sized lumps of melt on the irradiated surfaces [7] as well as melt spherules comparable in size (between ~10 µm and ~4 mm; typically 50-300 µm) to MMs. The melt spherules were ejected from the irradiation zone in the form of a fine melt spray that was sampled by a ceramic witness plate. Peak surface temperatures of the massive melts were >2100 °C for about 5 s [7]; quenching was facilitated in ambient air. Similar peak temperatures are assumed here for the fine melt spay. Characterization of the laser-produced melts by optical microscopy, µXRF, SEM-EDS, and EMPA is ongoing. Results and Discussion: We identified several sub-types of spherules among our laser-generated melts that closely resemble S-type, I-type, and G-type melted MMs or cosmic spherules as well as partially melted or scoriaceous MMs [1,2]. Most abundant among the investigated melt spherules were glassy as well as cryptocrystalline silicate spherules, the latter consisting of olivine microcrystals, silicate mesosatsis, and magnetite dendrites and often having knobby surfaces resembling 'turtleback' cryptocrystalline S-type MMs [1,2]. In addition, silicate spherules dominated by equant microphenocrysts or skeletal to hopper-shaped olivine microcrystals set in glassy matrix that resemble porphyritic S-type MMs as well as complex, often highly vesicular, spherical or irregular silicate droplets that resemble scoriaceous MMs [1,2] also occur among the laser-produced melts. The silicate spherules occasionally contain FeNi metal blebs or beads with highly variable Ni abundances (~10-90 wt% Ni) that form sub-spherical domains in the glass; others contain Ni-poor (typically <10 wt% Ni) wüstite or magnetite blebs or coatings that often contain Ni-rich FeNi metal blebs in their interior parts (i.e., away from the silicates). Spherules dominated by Ni-bearing wüstite or magnetite, or entirely consisting of iron oxides, also exist; these spherules resemble I-type MMs [8]. We also observed rare composite blebs of FeNi metal and sulfides which typically occur in the form of deformed objects or melt splashes. We semi-quantitatively determined the bulk compositions of the laser-generated spherules by SEM-EDS analysis of carbon-coated spherule exteriors, following methods outlined in [9]. The bulk compositions of the laser-generated melts can be explained by melting and mixing of the individual components of HaH 077 under oxidizing conditions. In binary plots such as Si-(Fe + Ni) or Mg-(Fe + Ni) as well as in ternary plots such as Si-Mg-(Fe + Ni), most bulk compositions plot onto mixing lines spanned by either HaH 077 olivine (Fa~20), pyroxene (Fs~18), and oxidized FeNi metal (i.e., FeO), whereas the FeNi metal spherules reflect highly fractionated, Fe-depleted kamacite or taenite starting compositions. Overall, the compositional range spanned by the laser-generated melts is consistent with the range spanned by average compositions of I-, G-, and S-type cosmic spherules [1,2,8,9]. Conclusions: Typical shapes, mineralogies, and bulk compositions of I-, G-, and S-type cosmic spherules were reproduced in melt spherules formed by laser-induced flash heating of an H5 ordinary chondrite. Our results shed light onto mixing trends typically documented in these cosmic spherules and illustrate how a suite of compositionally/mineralogically diverse suite of MMs can be produced from compositionally complex chondritic starting material. [ABSTRACT FROM AUTHOR]

Introduction: Fusion crusts form during the atmospheric entry heating of meteorites and preserve a record of the conditions that occurred in the last few seconds of their deceleration in the atmosphere [1]. Although fusion crusts are ubiquitous they are rarely characterised and studied because they obscure the primary features of meteorites. Here we report the results of a study of the fusion crust of the Winchcombe CM2 chondrite. The Winchcombe meteorite fell at 21:54 hours on 28 February 2021 in Gloucestershire in the UK and was recovered over the next week. The fall was observed on UKFAll network cameras and recorded by CCTV. The meteoroid had a low entry velocity compared to other observed falls of 13.5 km/s. Study of the fusion crust reveals unique textural features that testify to previously unknown processes related to vigorous degassing of this intensely altered CM2 chondrite. Methods: Six polished blocks of Winchcombe were studied using backscattered electron imaging, elemental mapping, energy dispersive spectroscopy (EDS), electron backscatter diffraction (EBSD) and micro-X-ray fluorescence (XRF). Apparent size distributions and abundances were obtained by threshold analysis using ImageJ. Results: The fusion crust consists of an inner thermally altered substrate and outer melted crust. The altered substrate exhibits unusually abundant dehydration cracks extending up to 5 mm into the meteorite. The crack network encompasses fragments up to 70 μm in diameter (dense rock equivalent) with increasing abundance with decreasing size. Loss of sheet-like habits for phyllosilicates and tochilinite testifies to progressive dehydration towards the exterior. The outer melted crust has a vesicular porphyritic texture with olivine phenocrysts and magnetite in a glassy mesostasis. Grain-size and magnetite abundance increase outwards similar to other CI/CM2 fusion crusts [2]. High Ni (<80 wt%) sulphide-metal droplets occur - often as menisci on vesicles. A magnetite rim occurs on the exterior surface and some vesicles, and include some tabular, rim-parallel magnetite crystals. Unique features in the fusion crust are oscillatory zoned olivine crystals, monolayers of magnetite and silicate warts. Monolayers form chains of magnetite crystals within the mesostasis that have tabular crystals similar to magnetite rims. EBSD data reveals [111] is parallel to the length of tabular crystals and is layer parallel in rims and monolayers. Oscillatory zoned crystals are equant with up to 4 Mg-rich zones. Silicate warts form lenticular features on the surface of the fusion crust and contain dendritic olivine - their compositions are, however, similar to the rest of the crust. Magnetite monolayers lie between warts and the underlying crust. Discussion: The unusualy high abundance of dehydration cracks suggests the tochlinite-rich matrix of the Winchcombe meteorite is particularly sensitive to dehydration, owing to the low decomposition temperature of this mineral (250oC [3]). Mechanical failure of the substrate, in part driven by gas pressure, is likely to inject large abundances of particulates into the meteoroid gas stream. Observations of episodic pulsed plasma in the trail of the fireball may be a phenomena associated with calving of the dehydrated substrate and generate thermal pulses explaining the presence of oscillatory zoning. Other features also are consistent with vigorous degassing. Magnetite monolayers appear to have formed as surface magnetite rims - owing to their similar alignment of tabular crystals. Trapping of surface magneite rims through collapse of melt protrusions is likely to explain how these layers become buried within the crust and is probably driven by perturbation of surface melt by rapid vesicle loss. Finally, silicate warts are likely to be droplets attached to the crust surface. Their dendritic textures suggest higher peak temperatures and strongly suggest they represent droplets removed from other stones in the shower. Warts represent the first discovery of intershower transport of ablation materials, possibly owing to enhanced ablation as a result of vigorous degassing. Implications: The fusion crust of the Winchcombe meteorite illustrates the complexity of processes affecting meteorites during atmospheric flight. Features such as magnetite monolayers and silicate warts have not previously been described, and may be unique to tochlinite-rich CM2 chondrites, which experience vigorous degassing. They may also allow ablation debris to be related to particular types of meteorite, thus providing a distributed record of the meteorite flux. Winchcombe underlines the utility of fusion crust, which should be routinely characterised in addition to meteorite interiors. [ABSTRACT FROM AUTHOR]

Nanostructured particles made from polystyrene and zinc oxide are synthesized by precipitation in miniemulsions and miniemulsion polymerization. There are two main applications for miniemulsions: the formation of sub-micron or nano-sized reactors for the precipitation of inorganic nanoparticles and the use of sub-micron or nano-sized droplets as templates for nanostructured particles. The latter includes the formation of the desired structures within a monomer droplet, which then is polymerized without changing its size or structure during the process. In this research article two approaches to combine both processes are presented: The zinc oxide nanoparticles are precipitated in an inverse miniemulsion of water droplets in a continuous monomer phase. The resulting miniemulsion is either distilled and the nanoparticles are forced into the monomer phase or the miniemulsion is used directly without distillation. In both cases the particle loaded monomer droplets are afterwards polymerized to hybrid nanoparticles. The focus is on the technological challenges in producing nano-sized, hybrid particles, especially in regard to continuous processing. [ABSTRACT FROM AUTHOR]

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Adenomatoid tumor with intra-testicular localization is rare. Although most reported cases arise from the epididymis, rare cases have been reported in the testicular tunica, spermatic cord, ejaculatory ducts, prostate and suprarenal recess. Adenomatoid tumors occur in both sexes and are also found in the uterus, ovary and fallopian tubes of the female genital tract. Adenomatoid tumors are benign proliferations of mesothelial origin. We report the case of a 50-year-old male with an adenomatoid tumor of the left testis. Because of its rarity, the clinical, diagnostic and therapeutic aspects as well as the possibilities of testicular preservation are discussed. [ABSTRACT FROM AUTHOR]

This paper reports on a survey conducted among elderly Chinese in Taiwan and Americans in eastern Oregon. The focus is on health status and selected social network characteristics (such as range, density, and percentage of relatives) as they relate to life satisfaction. In addition to examining differences among these and other variables in the two national samples, two hypotheses are tested using hierarchical regression analysis. The first hypothesis relates higher values of range and density to greater life satisfaction. The second is a test of the stress-buffering hypothesis. We then examine the data controlling for gender and conclude with a discussion and interpretation of both the national and gender differences yielded by this analysis. [ABSTRACT FROM AUTHOR]

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Background: The global prevalence of diabetes mellitus (DM) has been increasing over recent decades. In Germany, the prevalence for DM type 1 and type 2 in adults is estimated at about 7.7%. Hence, diabetes has to be classified as a serious public health concern. Being diagnosed with DM and facing possible sequelae might have a negative impact on patients' mental and physical well-being. However, diabetes not only affects patients themselves, but also their close relatives. To improve the quality of life for patients and relatives alike, the German Association of Diabetes Nurses and Education experts (VDBD) elaborated the first education program tailor-made for relatives of diabetes patients. This article describes the concept and design of the trial evaluating the efficacy of this education program called "DiaLife-Living Together with Diabetes".Methods: This evaluation study is a cluster randomized controlled trial, in which the study centers will be randomly assigned either to the intervention group or the control group. Study centers will recruit relatives of and patients with DM type 1 and type 2. Members of the intervention group will participate in the education program DiaLife, whereas participants randomized in the control group will act as waiting-list controls. The study will assess the efficacy of DiaLife by comparing diabetes-related knowledge between the intervention and control groups as the primary outcome for participants. As the primary outcome in patients, the Hba1c value will be assessed. In addition, diabetes-related distress, family interaction, and other secondary endpoints will be considered as secondary outcomes. Long-term efficacy will be assessed 6 and 12 months after intervention. Hierarchical regression models will be used to analyze effects over time.Discussion: While there is scientific evidence for the efficacy of education programs addressed to (diabetes) patients, there is a research gap with regard to intervention studies evaluating the efficacy of education programs designed for patients' relatives. The study results will provide information on the efficacy of the DiaLife education program. In addition, factors that might hinder a successful implementation of an education program for relatives will be identified.Trial Registration: German Clinical Trials Register, DRKS00015157 . Registered on 24 August 2018. [ABSTRACT FROM AUTHOR]

- We carried out hypervelocity cratering experiments with steel projectiles and sandstone targets to investigate the structural and mineralogical changes that occur upon impact in the projectile and target. The masses of coherent projectile relics that were recovered in different experiments ranged between 58% and 92% of their initial projectile masses. A significant trend between impact energy, the presence of water in the target, and the mass of projectile relics could not be found. However, projectile fragmentation seems to be enhanced if the target contains substantial amounts of water. Two experiments that were performed with 1 cm sized steel projectiles impacting at 3400 and 5300 m s−1 vertically onto dry Seeberger sandstone were investigated in detail. The recovered projectiles are intensely plastically deformed. Deformation mechanisms include dislocation glide and dislocation creep. The latter led to the formation of subgrains and micrometer-sized dynamically recrystallized grains. In case of the 5300 m s−1 impact experiment, this deformation is followed by grain annealing. In addition, brittle fracturing and friction-controlled melting at the surface along with melting and boiling of iron and silica were observed in both experiments. We estimated that heating and melting of the projectile impacting at 5300 m s−1 consumed 4.4% of the total impact energy and was converted into thermal energy and heat of fusion. Beside the formation of centimeter-sized projectile relics, projectile matter is distributed in the ejecta as spherules, unmelted fragments, and intermingled iron-silica aggregates. [ABSTRACT FROM AUTHOR]