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Stable soils provide valuable ecosystem services and mechanical soil stability is enhanced by the presence of arbuscular mycorrhizal fungi (AMF). Soil aggregation, which is the major driver of mechanical soil stability, is often treated as a static phenomenon, even though aggregate turnover is continually ongoing. In fact, some breakdown of macroaggregates is necessary to allow new aggregate formation and inclusion of new organic matter into microaggregates. We determined how aggregate turnover times were affected by AMF by tracking movement of rare earth elements (REE), applied as their immobile oxides, between aggregate size classes, and using X-ray fluorescence microscopy to spatially localize REEs in a sample of aggregates. Here we show that AMF increased large macroaggregate formation and slowed down disintegration of large and small macroaggregates. Microaggregate turnover was increased in the presence of AMF. Internal aggregate organization suggested that although formation of microaggregates by accretion of soil to particulate organic matter is common, it is not the only mechanism in operation.

Stable soils provide valuable ecosystem services and mechanical soil stability is enhanced by the presence of arbuscular mycorrhizal fungi (AMF). Soil aggregation, which is the major driver of mechanical soil stability, is often treated as a static phenomenon, even though aggregate turnover is continually ongoing. In fact, some breakdown of macroaggregates is necessary to allow new aggregate formation and inclusion of new organic matter into microaggregates. We determined how aggregate turnover times were affected by AMF by tracking movement of rare earth elements (REE), applied as their immobile oxides, between aggregate size classes, and using X-ray fluorescence microscopy to spatially localize REEs in a sample of aggregates. Here we show that AMF increased large macroaggregate formation and slowed down disintegration of large and small macroaggregates. Microaggregate turnover was increased in the presence of AMF. Internal aggregate organization suggested that although formation of microaggregates by accretion of soil to particulate organic matter is common, it is not the only mechanism in operation.

Barnard’s star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard’s star is also among the least magnetically active red dwarfs known2,3and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4–6, astrometry7,8and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard’s star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard’s star, making it an excellent target for direct imaging and astrometric observations in the future.

ABSTRACTSubstitution of bones is a well-established, necessary procedure to treat bone defects in trauma and orthopedic surgeries. For prevention or treatment of perioperative infection, the implantation of resorbable bone substitute materials carrying antibiotics is a necessary treatment. In this study, we investigated the newly formulated calcium-based resorbable bone substitute materials containing either gentamicin (CaSO4-G [Herafill-G]), vancomycin (CaSO4-V), or tobramycin (Osteoset). We characterized the released antibiotic concentration per unit. Bone substitute materials were implanted in bones of rabbits via a standardized surgical procedure. Clinical parameters and levels of the antibiotic-releasing materials in serum were determined. Local concentrations of antibiotics were measured using antimicrobial tests of bone tissue. Aminoglycoside release kinetics in vitroper square millimeter of bead surface showed the most prolonged release for gentamicin, followed by vancomycin and, with the fastest release, tobramycin. In vivolevel in serum detected over 28 days was highest for gentamicin at 0.42 μg/ml, followed by vancomycin at 0.11 μg/ml and tobramycin at 0.04 μg/ml. The clinical parameters indicated high biocompatibility for materials used. None of the rabbits subjected to the procedure showed any adverse reaction. The highest availability of antibiotics at 14.8 μg/g on day 1 in the cortical tibia ex vivowas demonstrated for gentamicin, decreasing within 14 days. In the medulla, vancomycin showed a high level at 444 μg/g on day 1, decreasing continuously over 14 days, whereas gentamicin decreased faster within the initial 3 days. The compared antibiotic formulations varied significantly in release kinetics in serum as well as locally in medulla and cortex.

Die Injektion an Sehnenansätze, in Muskeln oder Gelenke stellt ein wichtiges Instrument in der konservativen Behandlung von muskuloskeletalen Erkrankungen dar, sowohl für akute Verletzungen als auch für chronisch degenerative Krankheitsbilder. Lokalanästhetika oder Glukokortikoide sind dabei langjährig etablierte Medikamente. Gerade für die Anwendung von Lokalanästhetika wurden jedoch zum Teil schwere Nebenwirkungen (u. a. Chondrolysen) beschrieben. Ergänzt wird das Spektrum hauptsächlich durch plättchenreiches Plasma und Hyaluronsäure. Nicht immer ist allerdings die klinische Wirksamkeit bewiesen. Dieser Beitrag gibt eine Übersicht zu den gängigen injizierbaren Medikamenten und deren Wirkmechanismen. Unter Berücksichtigung der aktuellen Datenlage wird Stellung zu Indikationen bezogen sowie auf die Evidenz für die klinische Anwendung an Muskeln, Sehnen und Gelenken eingegangen. Injections at tendon insertions, in muscles and in joints are an important instrument in the conservative treatment of musculoskeletal diseases, for acute injuries as well as for chronic degenerative diseases. Local anesthetic agents and glucocorticoids are well-established medications; however, severe side effects, such as chondrolysis have sometimes been reported, particularly for local anesthetic agents. In addition platelet rich plasma (PRP) and hyaluronic acid are also widely used; however, the clinical effectiveness has not always been proven. This article gives an overview on the most commonly used medications for injections and the mechanisms of action. The indications for treatment and the evidence for the clinical adminstration of muscle, tendon and joint injections are described based on the currently available literature.

The intermediate-energy scanning x-ray microscope at beamline 2-ID-B at the Advanced Photon Source is a dedicated instrument for materials and biological research. The microscope uses a zone plate lens to focus coherent 1-4 keV x-rays to a 60 nm focal spot of 109photons/s onto the sample. It records simultaneous transmission and energy-resolved fluorescence images. We have used the microscope for nanotomography of chips and microspectroscopy of cells.

We describe the use of principle component analysis (PCA) to serve as a prefilter for cluster analysis or pattern récognition analysis of soft x-ray spectromicroscopy data. Cluster analysis provides a method to group régions with common spectral features even if no prior knowledge of their spectra is available, such as in biology or environmental science.

X-ray-microprobe-based X-ray fluorescence (XRF) scanning microscopy is a powerful technique to map and quantify element distributions in biological specimens, such as cells and bacteria.
Principal component analysis (PCA) provides a method to correlate an XRF data set with full spectra at each scan point and to weigh each component of the spectrum, and its corresponding eigenimage, according to its respective significance in the data set. In particular, photon noise is not correlated among pixels and therefore does not contribute to the principal components. We show that, by fitting the eigenspectra of the principal components, one can then generate maps of fitted elemental components with high accuracy, without the need to fit the spectra of single pixels. Additionally, the correlation of elemental distributions can be used to reveal information about the number and composition of the différent major constituents of a cell. We also demonstrate that cluster analysis can be used to classify the sample into spatially separate régions of characteristic elemental compositions, for example nucleus, cytoplasm, and vesicles.

With the new tomography setup developed for the x-ray microscope XM-1 installed at the Advanced Light Source, tomography of immunolabelled frozen-hydrated cells to detect protein distributions inside of cells was performed. The distribution of the nuclear protein, male specific lethal 1 (MSL-1) in the Drosophila melanogastercell was studied. Another application field for high resolution tomography which is of fundamental interest in materials science is electromigration in advanced copper interconnects. In this work, quantitative time-resolved x-ray microscopy mass transport studies of the early stages of electromigration in an inlaid Cu line/via structure were performed with 40 nm spatial resolution at 1.8 keV photon energy. Correlation of the real time x-ray microscopy images with post mortem high voltage electron micrographs of the sample shows that the void nucleation occurs at the site of grain boundaries in Cu and that the voids migrate along these grain boundaries during electromigration. To provide 3D information about the exact location (bulk or interface) of void nucleation and migration during an EM experiment, as well as to measure quantitatively the mass transport in the volume, future experiments must be based on time-resolved x-ray tomography.

X-ray fluorescence (XRF) imaging of biological cells typically involves the creation (and subséquent analysis) of 3-dimensional (3D) data sets, where at each scan position the full spectrum is recorded. This allows one to) later process the data in a variety of différent approaches, e.g., by spectral région of interest (ROIn) summation with or without background subtraction, principal component analysis, or fitting. Additionally, it is possible to sum up the per pixel spectra over selected spatial ROIs so as to improve the photon statistics in such a spectrum. A software package is presented here that implements these functions to provide a too) set for the analysis of 3D XRF data sets.

Background/Objectives:: The objective of this study was to quantify body weight changes in German adult populations during the past decades. Subjects/Methods:: Longitudinal analysis of seven cohort studies covering different age ranges between 18 and 83 years. Baseline examinations were between 1994 and 2007 and follow-up durations between 4.0 and 11.9 years. For each study, mean change in body weight per year and 10-year change in body mass index (BMI) classification were analyzed. For the middle age group of 45–64 years, meta-analysis was conducted to obtain an overall estimate for Germany. Results:: Among men weight gain was highest in the youngest participants and decreased with advancing age. Among women weight gain was on a stable high level among those younger than 45 years and decreased at older age. Within 10 years, 30–40% of middle-aged participants with normal baseline weight became pre-obese or obese and 20–25% of those with pre-obesity at baseline became obese, whereas >80% of persons who were obese at baseline remained obese over time. The estimated average weight change in adults aged 45–64 years was 0.25 (95% confidence interval (CI): 0.18–0.33) kg/year among men and 0.24 (0.17–0.30) kg/year among women. Conclusions:: We could observe a moderate weight gain over the past years in German middle-aged populations of 0.25 kg/year. Obesity prevention needs to be targeted to specific subgroups in the population, especially to younger adults, who seem to be most vulnerable for gaining weight. Obesity intervention needs to be improved, as the majority of obese adults remained obese over time.

We examined the association of baseline serum 25-hydroxyvitamin D (25(OH)D) with change in weight and total body fat in a cohort of community-dwelling older adults from Southern Germany. A total of 735 participants of the population-based KORA-Age Study (2009–2012), aged 65–90 years, were followed for 2.9±0.1 years. Body fat was assessed with bioelectrical impedance analysis. Linear and multinomial logistic models, adjusted for baseline covariables, were used to examine the association of 25(OH)D with percentage weight and body fat change during follow-up. 25(OH)D levels were not associated with overall weight change or body fat loss. Higher 25(OH)D levels were associated with a lower likelihood of having gained >3% of body fat in women but not in men. As we cannot exclude residual confounding by outdoor physical activity and diet, our results are not sufficient to support a causal role of 25(OH)D in the etiology of obesity in Caucasian older adults.

We report additional observations of the phase dependent behavior of the chromospheric Hαfeature associated with the K-dwarf component of V471 Tau. Previously, all such observations have shown a sharply defined maximum of emission near the middle of the transit phase of the white dwarf across the disk of the K-dwarf. The precision and the reproducibility of that phase lock led many previous observers to conclude that the observed emission was due to chromospheric re-processing of ultraviolet radiation incident upon the K-dwarf from the white dwarf. Comparing these observations with previously published observations, we show that the emission strength has been steadily diminishing between epoch 1985 and epoch 1992 whence it has essentially vanished. The ultraviolet flux from the white dwarf is constant so the resulting re-processed chromospheric emission cannot be time dependent. This leads to the conclusion that most of the emission has been due to magnetically active regions located preferentially at the sub-stellar point of the white dwarf. We propose that tidal coupling in this close binary system preferentially affects the transfer of magnetic energy, coupling the internal dynamo of the K-dwarf to the outer envelope, giving a preferred longitude to magnetic activity. We further suggest that this mechanism may be common in most short period binary systems and in many cases may be the dominant mechanism causing the observed Hαbehavior.

Objective To evaluate whether a sandwich technique procedure for large osteochondral lesions (OCL) of the medial femur condyle reduces clinical symptoms and improves activity level as well as to assess repair tissue integration on MRI over 2 years.Design Twenty-one patients (median age: 29 years, 18-44 years) who received matrix-associated autologous chondrocyte transplantation (MACT) combined with cancellous bone grafting at the medial femur condyle in a 1-step procedure were prospectively included. Patients were evaluated before surgery (baseline) as well as 3, 6, 12, and 24 months postoperatively, including clinical evaluation, Lysholm score, Tegner Activity Rating Scale, and MRI with Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score and a modified Whole-Organ Magnetic Resonance Imaging Score (WORMS).Results Seventeen patients were available for the 24-month (final) follow-up (4 dropouts). Lysholm significantly improved from 48 preoperatively stepwise to 95 at final follow-up (P< 0.05). Tegner improvement from 2.5 at baseline to 4.0 at final follow-up was not significant (P= 1.0). MOCART score improved significantly and stepwise from 65 at 3 months to 90 at 24 months (P< 0.05). Total WORMS improved from 14.5 at surgery to 7.0 after 24 months (P< 0.05). Body mass index and defect size at surgery correlated with total WORMS at final follow-up (P< 0.05) but did not correlate with clinical scores or defect filling.Conclusion MACT combined with cancellous bone grafting at the medial femoral condyle reduces symptoms continuously over 2 years. A 1-step procedure may reduce perioperative morbidity. However, despite improvements, patients’ activity levels remain low, even 2 years after surgery.

In a 1.5-year-old male hunting dog, a urethral defect distal to the pelvic flexure and the resulting urethral fistula were treated with a mucosal graft and a transurethral catheter. Six months postoperatively a stricture of the urethra occurred. Following balloon dilatation, urination was normal. One month after dilatation, urethral narrowing relapsed and was treated using a combination of balloon dilatation and urethral stent implantation. Ten months following stent implantation the dog continued to show normal urination, although a deformation of the proximal part of the stent was diagnosed radiographically. During the 1-year follow-up no additional complications were observed. In the future, urethral stents may replace surgical resection of the narrowed urethral region and re-anastomosis of the urethra.

AbstractA radioanalytical method based on the use of a single TRU extraction chromatographic column and selective, on-column oxidation state adjustment of actinides was developed for the determination of Th, U, Np, Pu and Am(Cm) in environmental samples (such as sediment and swipe samples). The procedure of Vajda et al.[1] was further investigated and optimized focusing on the separation of Th, U and Np. The improved method combines two measurement techniques — alpha spectrometry and inductively coupled plasma mass spectrometry (ICP-MS) – which allows to obtain more reliable information on a wider range of isotopes: 228Th, 230Th, 232Th, 234U, 235U, (236U), 238U, 237Np, 238Pu, 239Pu, 240Pu, 241Pu, 241Am, 242Cm, 243Cm and 244Cm from one sample.

Die Ätiopathogenese der osteochondralen Läsion des Capitulum humeri ist bis heute nicht abschließend geklärt. Abzugrenzen von der osteochondralen Läsion ist der M. Panner, einer juvenile Osteonekrose des gesamten Kapitulums.

Emerging areas of nanotechnology hold the promise of overcoming the limitations of existing technology for intracellular manipulation. These new developments include the creation of nanocomposites that can be introduced into the cells, targeted to specific subcellular sites, and subsequently used as platforms for initiation of intracellular processes dependent on or aided by locally high concentrations of specific molecules delivered as components of the nanocomposites. Nanocomposites that combine functional properties of biomolecules with the functional properties of inorganic components could provide new tools for biology, medicine, chemistry and material sciences. Here we describe how we introduced TiO2-DNA nanocomposites into cells, and localized titanium in the cells by mapping the Ti KαX-ray fluorescence induced at the 2-ID-E microprobe of the SRI-CAT at the Advanced Photon Source at Argonne National Laboratory.

In the current study a new composite material comprising calcium sulphate, calcium carbonate, and tripalmitin was developed as a bioresorbable drug carrier for the local antibiotic therapy. Device fabrication can be simply performed by compression moulding of the components. The evaluated bone substitute material based on a calcium sulphate/calcium carbonate composite exhibits an excellent biocompatibility and a therapeutically useful release profile. It, therefore, represents a promising new antibiotic delivery system for the efficient prevention and treatment of bone infections.