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To evaluate the clinical and radiological outcome, sum of acetabular and femoral cartilage thickness, and rate of failure in the midterm after arthroscopic treatment of femoroacetabular impingement (FAI) syndrome with femoral osteoplasty, labral repair, and rim trimming without labral detachment.This retrospective case series included patients with FAI syndrome who had undergone hip arthroscopy from January 2009 to December 2010 by a single surgeon, with a minimum follow-up of 55 months. Data from patients who had undergone arthroscopic hip procedures with labral repair, rim trimming, and femoral osteoplasty were analyzed pre- and postoperatively. Clinical outcome (nonarthritic hip score [NAHS], Short Form 36 [SF-36]), range of motion, progression of osteoarthritis (Tönnis grade), radiological parameters (α angle, lateral center-edge angle [LCEA], Tönnis angle), femoral and acetabular cartilage thickness (using magnetic resonance imaging [MRI]), and intraoperative findings were evaluated.Of 148 hip arthroscopies performed, 97 included rim trimming, labral refixation, and femoral osteoplasty. Ten cases were lost to follow-up, leaving 87 hips. Arthroscopic revision was performed on 4 hips and total hip replacement on 4 hips, and 1 hip underwent both arthroscopic revision and total hip replacement. Excluding these 9 cases of revision, for which follow-up was not possible (retrospective study), the remaining 78 hips were followed up for a minimum of 55 months (77 ± 11.4, mean ± SD; range 55 to 124). Mean NAHS (65 to 88, P.001), SF-36 physical subscale (65 to 85, P.001), and the numerical pain rating scale (NRS) (5 to 1, P.001) improved significantly. Outcome scores of minimal clinical importance (NAHS) were achieved in 67.6% of the patients. Mean range of movement improved significantly in flexion (109 to 122, P .001) and internal rotation (10 to 22.7, P.001). NAHS was positively associated with flexion of the hip postoperatively (r = 0.307, P = .011). In 16 cases, microfracture was performed (15 acetabular and 1 femoral). Preoperative α angles (anteroposterior and modified Dunn) were significantly higher in this cohort (P.001, 95% confidence interval 8.9 to 25.2, P = .001). Twenty hips (28 %) progressed to worse Tönnis grades. Initial Tönnis grades were grade 0, 38; grade 1, 48; grade 2, 8. Pre- or postoperative Tönnis grades did not show any correlation with pre- or postoperative NAHS and NRS. MRI measurements at the latest follow-up (69 patients) of the femoral and acetabular cartilage thickness did not reveal any significant reduction at the 12 o'clock position.Arthroscopic cam resection, rim trimming, and labral repair without detachment of the labrum provides good or excellent outcome in 77.1% of hips based on NAHS in the midterm. Higher range of motion in flexion is associated with higher NAHS postoperatively. Arthroscopic cam resection, rim trimming and labral repair without detachment of the labrum is a successful method for the treatment of FAI syndrome in the midterm.IV, retrospective case series.

This article focuses on convict labour in the Namibian–Cape border region in the late 19th and early 20th centuries. It situates this form of unfree labour within broader trans-colonial discussions...

The presence of tektite-like glasses from a geographically restricted area in Belize (Central America) has been known for several decades. We comprehensively studied 18 such Belize glasses by a variety of petrographic and geochemical methods, including major and trace element analysis, radiogenic isotopic composition (Rb-Sr, Sm-Nd, and Re-Os), water content, oxidation state, and cosmogenic radionuclides. The aims were to determine their compositional variation, their mode of formation and possible source rocks, and their relation to known tektites, and to search for evidence of an extraterrestrial component. In terms of petrography, the samples are similar to tektites from the four “classical” strewn fields, with the presence of lechatelierites, schlieren, and vesicles; these are also widely accepted indicators of an impact origin. No close similarities to volcanic glasses are evident. Water contents are very low, and iron oxidation states are mostly reduced, in both cases similar to observations for other tektites. The geochemical and isotopic data presented, such as Cr, Co and Ni elemental abundances and interelement ratios, as well as trace element patterns are typical for local and regional volcanics from the active Central American Arc. Particular similarities to material comparable to volcanic rocks from Honduras or Guatemala are noted. This is confirmed by Sr-Nd isotope signatures of the Belize glasses, showing close similarities to Central American volcanics in general, and Honduran and Guatemalan volcanic, in particular. Osmium concentrations and 187Os/188Os ratios are comparable to arc volcanics from world-wide locations, but - in a few of the samples - elevated Ir concentrations, near-chondritic Pt/Ir and 187Os/188Os ratios can also be interpreted with the admixture of a minor meteoritic component to some of the Belize samples. 10Be concentrations are consistent with values typical of both, young or deeply buried soils and with values for Central American volcanics, which carry subducted 10Be. Geochemical data clearly indicate a source different from that of the Australasian tektites. Both isotope data sets for the Belize glasses indicate a close relationship to local arc lavas, especially those from Guatemala and Honduras, suggesting that the glasses were not deposited very far from their source. The main evidence that the Belize glasses are of impact origin are their petrographic characteristics and low water content. The evidence from 10Be is consistent with, but does not require, a model of formation for the Belize glasses by an impact on loosely consolidated surface sediments exposed to rain. A probable meteoritic component is low and heterogeneously distributed.

International audience; The Martian breccias NWA 7034, NWA 7533, and paired meteorites record events ranging in age from 4.47 Ga to 1 wt% K and thought to be rich in feldspar and one containing

The conflation of labour activism and political activism in Namibian history and historiography - or views of a seamless transition between the two - has meant that meaningful empirical historical studies of labour relations and labour policy in Namibia have been downplayed, leaving scholars to rely on older, potentially outdated studies. The articles in this part-special issue de-centre Namibian nationalism from the economic and labour history of Namibia, instead re-centring the labour process, labour policy and the lived history of labourers themselves. Studying labour history necessitates working at multiple scales. Global labour history (GLH) frameworks, in conjunction with transnational and microhistory methodologies, enable deep consideration of structural transformations in globally interconnected economies as well as local contingent factors. GLH has helped to guide labour historians to balance both global and local scales. The articles in this special issue draw from new archival and oral history sources in order to reinvestigate central themes in Namibian labour history and to open new vistas for future research.

Selective dealloying of metal nanoparticles results in rattle-type hollow carbon nanoshells enclosing platinum nanoparticles, which are able to perform size-selective catalysis. Selective functionalization of the outer graphene-like carbon surface prevents agglomeration and leads to well dispersible nanocatalysts in aqueous solutions. The synthesis starts with the production of nanoparticles with a cobalt–platinum-alloy core surrounded by graphene-like carbon via reducing flame spray synthesis. After surface functionalization, simultaneous pore formation in the shell-wall and dissolution of the cobalt results in platinum encapsulated in hollow carbon nanospheres. Catalytic oxidation of differently sized sugars (glucose and maltoheptaose) reveales size-selective catalytic properties of these platinum nanorattles., Chemical Science, 9 (2), ISSN:2041-6520, ISSN:2041-6539

It is a desireable reaction to shift the double bond of the naturally abundant oleic acid from plant oils to the terminal position to enable suitable hydrosilylation or other hydrometallations to obtain intermediates of polymer manufacture. The catalyst [Ir(OMe)(1,5-cod)]2 is able to catalyze the 8-fold isomerisation using simple alkyl silanes as reactant, but technically more interesting alkoxysilanes do not react. It was found that combined application of HCo(N2)(PPh3)3 and Wilkinson´s catalyst isomerize and hydrosilylate oleic acid to the desired ω-triethoxysilyloctadecanoic acid ethylester but with still poor yield. Considerable improvement was found when the phosphanes are changed, i.e. tris-p-tolylphosphane being the most effective yielding nearly 50% terminally hydrosilylated oleic acid ester.

When cosmic dust particles were first identified almost 140 years ago, few would have predicted that much would ever be known about these miniscule objects, given the existing state of the art in analytical techniques. Times have changed. Today, in a single extraterrestrial dust particle, we can detect all the elements present, measure isotopic ratios, determine the exact crystalline structures of the minerals and the oxidation state of cations in those minerals, and even resolve individual atoms. The results are telling fascinating stories about the nature and histories of the particles that come to Earth. We review the most common techniques that help unravel these cosmic stories.

Objective: To investigate the value of MRI in comparison to single photon emission computed tomography (SPECT)/CT in patients with painful hip arthroplasties. Methods: A prospective, multi-institutional study was performed. Therefore, 35 consecutive patients (21 female, 14 male, mean age 61.8 ± 13.3 years) with 37-painful hip arthroplasties were included. A hip surgeon noted the most likely diagnosis based on clinical examination and hip radiographs. Then, MRI and SPECT/CT of the painful hips were acquired. MRI and SPECT/CT were assessed for loosening, infection, fracture, tendon pathology and other abnormalities. Final diagnosis and therapy was established by the hip surgeon after integration of MRI and SPECT/CT results. The value of MRI and SPECT/CT for diagnosis was assessed with a 3-point scale (1 = unimportant, 2 = helpful, 3 = essential). Results: Loosening was observed in 13/37 arthroplasties (6 shaft only, 6 cup only, 1 combined). Sensitivity, specificity, positive predictive value and negative predictive value for loosening of MRI were 86%/88%/60%/100% and of SPECT/CT 93%/97%/90%/100%, respectively. MRI and SPECT/CT diagnosed infection correctly in two of three patients and fractures in two patients, which were missed by X-ray. MRI detected soft tissue abnormalities in 21 patients (6 bursitis, 14 tendon lesions, 1 pseudotumor), of which only 1 tendon abnormality was accurately detected with SPECT/CT. All 5 arthroplasties with polyethylene wear were correctly diagnosed clinically and with both imaging modalities. MRI and SPECT/CT were judged as not helpful in 0/0%, as helpful in 16%/49% and essential in 84%/51%. Conclusion: In patients with painful hip arthroplasty SPECT/CT is slightly superior to MR in the assessment of loosening. MRI is far superior in the detection of soft tissue, especially tendon pathologies. Advances in knowledge: To our knowledge this is the first prospective, multiinstitutional study which compares MRI with SPECT/CT in painful hip arthroplasties. We found that MRI is far superior in the detection of soft tissue pathologies, whereas SPECT/CT remains slightly superior regarding loosening.

Three masses of the Chelyabinsk meteorite have been studied with a wide range of analytical techniques to understand the mineralogical variation and thermal history of the Chelyabinsk parent body. The samples exhibit little to no postentry oxidation via Mossbauer and Raman spectroscopy indicating their fresh character, but despite the rapid collection and care of handling some low levels of terrestrial contamination did nonetheless result. Detailed studies show three distinct lithologies, indicative of a genomict breccia. A light-colored lithology is LL5 material that has experienced thermal metamorphism and subsequent shock at levels near S4. The second lithology is a shock-darkened LL5 material in which the darkening is caused by melt and metal-troilite veins along grain boundaries. The third lithology is an impact melt breccia that formed at high temperatures (~1600 °C), and it experienced rapid cooling and degassing of S2 gas. Portions of light and dark lithologies from Chel-101, and the impact melt breccias (Chel-102 and Chel-103) were prepared and analyzed for Rb-Sr, Sm-Nd, and Ar-Ar dating. When combined with results from other studies and chronometers, at least eight impact events (e.g., ~4.53 Ga, ~4.45 Ga, ~3.73 Ga, ~2.81 Ga, ~1.46 Ga, ~852 Ma, ~312 Ma, and ~27 Ma) are clearly identified for Chelyabinsk, indicating a complex history of impacts and heating events. Finally, noble gases yield young cosmic ray exposure ages, near 1 Ma. These young ages, together with the absence of measurable cosmogenic derived Sm and Cr, indicate that Chelyabinsk may have been derived from a recent breakup event on an NEO of LL chondrite composition.

We report 40Ar/39Ar ages for several lithological components of the brecciated howardite Kapoeta and compare the ages with results for asteroid 4 Vesta as observed by the Dawn mission. Our Kapoeta sample has an unusual, millimeter wide glass vein that intruded into a complex breccia. The plateau ages of three lithic clasts of basaltic composition that were remote from the glass vein range from 4.2 to 4.5 Ga. Such ages are typical of eucritic material; the oldest reflects early magmatic crystallization ( ∼ 4.5 Ga ), the younger (4.2–4.5 Ga) reflect magmatism associated with protracted cooling. Samples of the glass vein itself, which include relict grains, give apparent ages between 3.1 and 3.9 Ga as do chips from the matrix. We consider both glass and bulk matrix ages as mixing ages; not marking the time of a single event, but dating regolith activity ( 3.1 – 4.1 Ga ). Eight feldspar grains close to the glass vein give markedly younger plateau ages averaging 1.4 Ga. The Ar release spectra for glass vein and breccia subsamples indicate a disturbance in the last 1.4 Ga. Taken together, these younger ages suggest a recent, major thermal event in the history of howardites that has been under-reported – perhaps the impact that formed the Rheasilvia basin on Vesta.

We analyzed cosmogenic nuclides in metal and/or silicate (primarily olivine) separated from the main-group pallasites Admire, Ahumada, Albin, Brahin, Brenham, Esquel, Finmarken, Glorieta Mountain, Huckitta, Imilac, Krasnojarsk, Marjalahti, Molong, Seymchan, South Bend, Springwater, and Thiel Mountains and from Eagle Station. The metal separates contained an olivine fraction which although small

We review recent experimental and theoretical work on the quantum oscillations of the magnetization M, i.e., the de Haas–van Alphen (dHvA) effect, in two-dimensional electron systems (2DESs) with spin–orbit interaction (SOI). We focus first on a theoretical modeling by numerically solving the Hamiltonian including the Rashba (R) and Dresselhaus (D) SOI and the Zeeman term in an arbitrarily tilted magnetic field B. We second present experimental data on the SOI-modified quantum oscillations of in 2DESs formed in the InGaAs/InP and AlGaAs/GaAs material systems for different tilt angles between the 2DES normal and the direction of B. We find pronounced beating patterns in InGaAs/InP that are described quantitatively by assuming a dominant R-SOI except for a distinct frequency anomaly in M present in nearly perpendicular B. In AlGaAs/GaAs, beating patterns occur at large tilt angles. Here, anomalies in the dHvA wave form occur. The findings demonstrate that the understanding of the ground state energy of a 2DES is incomplete when SOI is present. Finally, we predict that the amplitude and anisotropy of specific dHvA oscillations with respect to the in-plane magnetic field component allow one to quantify the magnitude and relative signs of both R-SOI and D-SOI when simultaneously present. Calculated fan chart of Landau levels and oscillatory Fermi energy in a 2DES subject to SOI. The beating patterns in contain information on the SOI. They manifest itself in a variety of experimentally accessible observables. In this feature article, we focus on the magnetization M as a thermodynamic state variable. The inset sketches a micromechanical cantilever magnetometer used to measure M using the torque .

40 Ar/ 39 Ar ages of single feldspar grains from the paired meteorites Graves Nunatak 06128 (GRA8; 8 grains) and 06129 (GRA9; 26 grains) are presented. Plateau ages (⩾70% of the 39 Ar released) ranged from 4000 to 4600 Ma with an average 1-σ uncertainty of ±90 Ma. The most precise ages obtained were 4267 ± 17 Ma for a grain from GRA8 and 4437 ± 19 Ma and 4321 ± 18 Ma for two grains from GRA9. Isotope correlation diagrams yield less precise ages ranging from 3800 to 5200 Ma with an average 1-σ uncertainty of 250 Ma; they indicate a negligible trapped component. Plateau ages, integrated total fusion ages, and isochron ages are internally concordant at the 95% confidence level. The distribution of the plateau ages for GRA9 is bimodal with peaks at 4400 and 4300 Ma. In contrast, the plateau age distribution for GRA8 peaks at about 4260 Ma with broad wings extending toward younger and older ages. To explain the distributions of grain ages we prefer a scenario that includes a major post-formation event about 4400 Ma ago and a later melt intrusion event that heated GRA8 more than some parts of GRA9.

Lunar soil samples reveal an unusually high level of radioactive iron, which suggests a supernova in our vicinity within the last few million years.

– To determine the role played by sulfides in the formation of vesicles and FeNi metal beads, we mapped the locations and tabulated the numbers of sulfides, metal beads, and vesicles in 1583 sectioned micrometeorites (MMs) using conventional microscopy and in 190 whole MMs using synchrotron computed microtomography (SCMT). Both the section and the SCMT images show that sulfides melt, coalesce, and migrate to the MMs surface. The decomposition of sulfides may occur during all these stages. Given the sulfide morphologies and compositions that we see in section, we think the breakdown of Ni sulfides produces the FeNi beads. The SCMT images show that metal beads are common in melted MMs, >50% have them. Vesicles in porphyritic and scoriaceous MMs are also probably formed as sulfides decompose. Not only do sulfides abut the vesicles but also the temperatures at which sulfides decompose overlap those at which MM surfaces first melt and temporarily seal, suggesting that S gases could produce most of these vesicles. As the vesicle shapes and patterns of distribution differ among MM classes, tomography can be used to nondestructively screen for specific types of MMs. Tomography is a powerful tool for visualizing the three-dimensional distribution of metal beads, sulfides, mean densities, and vesicles in MMs.

This paper focuses on the determination of the speciation in calcium-silicate glasses from Raman spectra and describes in detail the statistical method to determine quantitatively the speciation from collected spectra. We developed a novel statistical method employing optimization technique to determine the number of active species and partial spectral contributions for overlapped spectra. This method allows deconvoluting overlapping spectra from spectral data such as UV-vis, Raman, X-ray, photoelectron spectroscopy (XPS), or other. We treat spectral methods that have absolute and relative information. By viewing the data as noisy or uncertain, we put all steps to deconvolute spectral data on a unified statistical approach, which allows to model spectral data with more realism. The suggested method enables us to calculate from overlapping spectra directly the individual contributions of each active component (species) present in the system without making any assumptions on the shape or peak positions of the components in individual spectra. To determine quantitatively the speciation in calcium silicate glasses, we have collected Raman spectra of the glasses in the range of 45 to 52 mol% SiO 2 . The spectra are strongly overlapped, and therefore, cannot be directly deconvoluted. Therefore, spectra were deconvoluted using our statistical approach. This lead to the discovery of partial spectra, which can be attributed to contributions of three different species. In addition, we have determined the equilibrium constant for the reaction (1) \[2Q^{2}\ {\leftrightarrow}\ Q^{1}\ +\ Q^{3}\] where logK 2 is found to be 1.15 ± 0.1, being in good agreement with available NMR study.

– We report measurements of cosmogenic nuclides in up to 11 bulk samples from various depths in Norton County. The activities of 36Cl, 41Ca, 26Al, and 10Be were measured by accelerator mass spectrometry; the concentrations of the stable isotopes of He, Ne, Ar, and Sm were measured by electron and thermal ionization mass spectrometry, respectively. Production rates for the nuclides were modeled using the LAHET and the Monte Carlo N-Particle codes. Assuming a one-stage irradiation of a meteoroid with a pre-atmospheric radius of approximately 50 cm, the model satisfactorily reproduces the depth profiles of 10Be, 26Al, and 53Mn (

Recently the relevance of femoroacetabular impingement as a cause of hip and groin pain in sportsmen has been recognized. The entity often poses diagnostic and therapeutic problems to the sports physician. The patients go through an odyssey of different diagnostic and therapeutic modalities before the correct diagnosis is made and an adequate therapy is implemented. Not seldom, patients get even operated at another site which is thought to cause the problems. The present review analyzes the current literature concerning diagnostic standards and therapy of femoroacetabular impingement focussing on their relevance for sports medicine. It is aimed to help the sports physician to recognise this entity as a cause for groin and hip pain in the athlete and realise its importance for the short term performance of the athlete and its long term significance in terms of development of early hip osteoarthrosis.

Purpose The aim of this study was to evaluate the short-term results after arthroscopic femoroacetabular impingement (FAI) correction combined with additional procedures addressing labral and chondral damages in patients who showed generalized severe cartilage lesions intraoperatively. Methods Between 2004 and 2007, 20 patients (16 men and 4 women) could be included in the study. Clinical parameters, the pain score on a visual analog scale, initial radiologic degenerative changes, the alpha angle, and the Nonarthritic Hip Score were prospectively documented. The study endpoint was the implantation of a total hip arthroscopy or the latest follow-up. Results At a mean follow-up of 3.0 years, 10 patients (50%) had undergone, or planned to undergo, total hip replacement. The remaining patients showed a significant improvement in pain, Nonarthritic Hip Score, and hip flexion and internal rotation. Conclusions In patients with already marked generalized chondral lesions, arthroscopy does not have any effect beyond the short-term pain relief resulting from debridement. The study underlines the fact that FAI with advanced osteoarthrosis, particularly Tonnis grade III, is not an indication for arthroscopic FAI correction. Level of Evidence Level IV, therapeutic case series.

We used ICP–MS to measure the elemental concentrations and isotopic abundances of Cu and Zn in: nine Ti-rich lunar basalts (10017, 10022, 10024, 10057, 70215, 71055, 74255, 75055, and 75075); size-separated samples prepared by sieving of pyroclastic black glass 74001, orange glass 74022, and the lunar soils 15021, 15231, 70181, and 79221; a basalt from the Piton des Neiges volcano, Reunion Island; two samples of Pele’s hairs from the Nyiragongo volcano, Democratic Republic of Congo, and the martian meteorite Zagami. The isotopic fractionation of zinc in lunar basalts and Zagami is mass dependent relative to a terrestrial standard (JMC 400882B). These and published results imply that lunar, terrestrial, meteoritic, and perhaps martian zinc all come from one or more reservoirs linked by mass-dependent fractionation processes. Relative to terrestrial basalts, Ti-rich lunar basalts are enriched in the heavier isotopes of Cu and Zn: we find for Ti-rich lunar basalts the following ranges and averages ±1 − σ (‰): δ65Cu/63Cu ≡ δ65Cu, 0.1–1.4, 0.5 ± 0.1‰ (N = 7); δ66Zn/64Zn ≡ δ66Zn = 0.2–1.9, 1.2 ± 0.2‰ (N = 8; 10017 excluded). For two terrestrial samples, we find δ66Zn ∼ +0.3‰ and δ65Cu ∼ 0‰, which are consistent with published values. The differences between the lunar basalts and terrestrial basalts could reflect minor, planetary-scale vaporization or igneous processes on the Moon. Data for size separates of the pyroclastic glasses 74001 and 74220 confirm the well-known surface correlation of Cu and Zn, but modeling calculations reveal no sharp differences between either the elemental ratios or the isotopic composition of grain interiors and exteriors. The absence of such differences indicates that the isotopic compositions for bulk samples are dominated by a light-isotope-rich surface component. Data for size separates of lunar soils also confirm the surface correlation of Cu and Zn, but an enrichment of heavy rather than light isotopes. Averages for bulk lunar soils from this work and the literature are (‰): δ65Cu, from 1.4 to 4.1, average 3.0 ± 0.3 (N = 9); δ66Zn, from 2.2 to 6.4, average 4.0 ± 0.3 (N = 14). As with the glasses, in all but soil 15231 our data show no strong differences between the isotopic composition of soil sub-samples with small and large grains. The size of the isotopic fractionation inferred for the surface component in the soils is 3× smaller than predicted by a published model of sputtering primarily by solar particles. At the same time, the observed fractionation is larger than predicted by calculations based on a model of micrometeorite impact heating and hydrodynamic quenching. Because impact heating appears unable to explain the observations, we conclude that sputtering must be important even though samples with very large isotopic fractionation of Cu and Zn have not yet been found.

Purpose The purpose of this study was to investigate the impact of a new computed tomography–based computer navigation system on the accuracy of arthroscopic offset correction in patients with cam type femoroacetabular impingement (FAI), and to evaluate if the accuracy of offset restoration compromises the early clinical outcome. Methods We prospectively treated 50 patients (25 navigated and 25 non-navigated) by hip arthroscopy and arthroscopic offset restoration for cam FAI. The patients were a mean age 42.9 years, and the average follow-up was 26.7 months, with no patients lost to follow-up. Magnetic resonance imaging scans were performed preoperatively and 6 weeks postoperatively. A postoperative alpha angle of less than 50° or a reduction of the alpha angle of more than 20° was considered to be successful offset restoration. Outcomes were measured with a visual analogue scale for pain, range of motion, and the nonarthritic hip score. Results The mean alpha angle improved from 76.5° (range, 57° to 110°) to 54.2° (range, 40° to 84°). In both the navigated and the non-navigated groups, 6 patients (24%) showed insufficient offset correction. Range of motion, visual analogue scale for pain scores, and nonarthritic hip scores significantly improved in all subgroups. Statistical analysis showed no significant difference regarding the clinical outcome between patients with sufficient and insufficient correction of the alpha angle. Conclusions In this series, a significant percentage of patients (24%) showed an insufficient correction of the alpha angle after hip arthroscopy for cam FAI. This study shows that the presented navigation system could not improve this rate and that the insufficient accuracy of reduction of the alpha angle does not appear to compromise the early clinical outcome. Level of Evidence Level II, prospective comparative study.

We report electron microprobe determinations of the elemental compositions of 11 Australasian layered tektites and 28 Australasian microtektites; and ion microprobe determinations of the 41 K/ 39 K ratios of all 11 tektites and 13 of the microtektites. The elemental compositions agree well with literature values, although the average potassium concentrations measured here for microtektites, 1.1-1.6 wt%, are lower than published average values, 1.9-2.9 wt%. The potassium isotope abundances of the Australasian layered tektites vary little. The average value of δ 41 K, 0.02 ± 0.12‰ (1σ mean), is indistinguishable from the terrestrial value (= 0 by definition) as represented by our standard, thereby confirming four earlier tektite analyses of Humayun and Koeberl (2004). In agreement with those authors, we conclude that evaporation has significantly altered neither the isotopic nor the elemental composition of Australasian layered tektites for elements less volatile than potassium. Although the average 41 K/ 39 K ratio of the microtektites, 1.1 ± 1.7‰ (1σ mean), is also statistically indistinguishable from the value for the standard, the individual ratios vary over a very large range, from −10.6 ± 1.4‰ to +13.8 ± 1.5‰ and at least three of them are significantly different from zero. We interpret these larger variations in terms of the evaporation of isotopically light potassium; condensation of potassium in the vapor plume; partial or complete stirring and quenching of the melts; and the possible uptake of potassium from seawater. That the average 41 K/ 39 K ratio of the microtektites equals the terrestrial value suggests that the microtektite-forming system was compositionally closed with respect to potassium and less volatile elements. The possibility remains open that 41 K/ 39 K ratios of microtektites vary systematically with location in the strewn field.

The L chondrite Patuxent Range (PAT) 41 91501 is an 8.5-kg unshocked, homogeneous, igneous-textured impact melt that cooled slowly compared to other meteoritic impact melts in a crater floor melt sheet or sub-crater dike. We conducted mineralogical and tomographic studies of previously unstudied mm- to cm-sized metal-sulfide-vesicle assemblages and chronologic studies of the silicate host. Metal-sulfide clasts constitute about 1 vol.%, comprise zoned taenite, troilite and pentlandite, and exhibit a consistent orientation between metal and sulfide and of metal-sulfide contacts. Vesicles make up approximately 2 vol.% and exhibit a similar orientation of long axes. Ar-39-Ar-40 measurements date the time of impact at 4.461 +/- 0.008 Gyr B.P. Cosmogenic noble gases and Be-10 and Al-2l activities suggest a pre-atmospheric radius of 40-60 cm and a cosmic ray exposure age of 25-29 Myr, similar to ages of a cluster of L chondrites. PAT 91501 dates the oldest known impact on the L chondrite parent body. The dominant vesicle-forming gas was S2 (approximately 15-20 ppm), which formed in equilibrium with impact-melted sulfides. The meteorite formed in an impact melt dike beneath a crater, as did other impact melted L chondrites, such as Chico. Cooling and solidification occurred over approximately 2 hours. During this time, approximately 90% of metal and sulfide segregated from the local melt. Remaining metal and sulfide grains oriented themselves in the local gravitational field, a feature nearly unique among meteorites. Many of these metal sulfide grains adhered to vesicles to form aggregates that may have been close to neutrally buoyant. These aggregates would have been carried upward with the residual melt, inhibiting further buoyancy-driven segregation. Although similar processes operated individually in other chondritic impact melts, their interaction produced the unique assemblage observed in PAT 91501.

FR2116; International audience; Observed patterns of species richness at landscape scale (gamma diversity) cannot always be attributed to a specific set of explanatory variables, but rather different alternative explanatory statistical models of similar quality may exist. Therefore predictions of the effects of environmental change (such as in climate or land cover) on biodiversity may differ considerably, depending on the chosen set of explanatory variables. Here we use multimodel prediction to evaluate effects of climate, land-use intensity and landscape structure on species richness in each of seven groups of organisms (plants, birds, spiders, wild bees, ground beetles, true bugs and hoverflies) in temperate Europe. We contrast this approach with traditional best-model predictions, which we show, using cross-validation, to have inferior prediction accuracy. Multimodel inference changed the importance of some environmental variables in comparison with the best model, and accordingly gave deviating predictions for environmental change effects. Overall, prediction uncertainty for the multimodel approach was only slightly higher than that of the best model, and absolute changes in predicted species richness were also comparable. Richness predictions varied generally more for the impact of climate change than for land-use change at the coarse scale of our study. Overall, our study indicates that the uncertainty introduced to environmental change predictions through uncertainty in model selection both qualitatively and quantitatively affects species richness projections.

A mathematical approach was developed to interpret Raman spectra of binary silicate glasses and melts without the necessity of external calibration, e.g., from NMR spectroscopy. The developed approach is based on Principal Component Analysis (PCA), linear combinations of partial Raman spectra and a linear optimization technique. In order to apply and to test this approach, we developed an experimental method to collect a large number of Raman spectra efficiently. We applied the quantification and the experimental approaches to investigate potassium silicate glasses with compositions from 17.4 to 38 mol% K 2 O. The equilibrium constant for the reaction 2 Q 3 ⇄ Q 2 + Q 4 was found log K 3 = −2.37 ± 0.07, in excellent agreement with NMR studies for the same glasses.

Ten glass cosmic spherules (CS) from the South Pole water well collection were analyzed by electron microprobe. Nine of them have Fe/Mn and Fe/Mg ratios in the range typical of chondrites. One of them (SP37-3), along with up to six other previously analyzed CS, have nonchondritic Fe/Mn and Fe/Mg ratios that agree well with values typical of either (basaltic) howardite, eucrite, and diogenite (HED) meteorites or Martian basalts, but not of lunar samples. SP37-3 also contains an anorthite relic grain. Anorthite has not previously been reported in cosmic spherules, but is well known in HED meteorites. The much greater frequency of HEDs among hand-sized meteorites suggests but does not prove that HED precursors are more likely for the nonchondritic spherules.We estimate that HED-like micrometeorites constitute 0.5 ± 0.4% of the total population of micrometeorites in the South Pole water well, a fraction that translates to a flux of 1.6 ± 0.3 x 10^(-8) g HED micrometeorites/m^2-y. The ratio of HED-like objects to carbonaceous objects is about 100 times less in micrometeorites than among hand-size specimens. We infer that the comparative mechanical weakness of carbonaceous precursor materials tends to encourage spherule formation.

The increasing molecular understanding of many diseases today permits the development of new diagnostic methods. However, few easy-to-handle and inexpensive tools exist for common diseases such as food disorders. Here we present a living material based analytical sensor (LiMBAS) containing genetically modified bacteria (Escherichia coli) immobilized and protected in a thin layer between a nanoporous and support polymer membrane for a facile quantification of disease-relevant oligosaccharides. The bacteria were engineered to fluoresce in response to the analyte to reveal its diffusion behavior when using a blue-light source and optical filter. We demonstrated that the diffusion zone diameter was related semi-logarithmically to the analyte concentration. LiMBAS could accurately quantify lactose or galactose in undiluted food samples and was able to measure food intolerance relevant concentrations in the range of 1–1000 mM requiring a sample volume of 1–10 μL. LiMBAS was storable for at least seven days without losing functionality at 4 °C. A wide range of genetic tools for E. coli are readily available thus allowing the reprogramming of the material to serve as biosensor for other molecules. In combination with smartphones, an automated diagnostic analysis becomes feasible which would also allow untrained people to use LiMBAS.