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Driven by the growing threat of antimicrobial resistance, the design of intrinsically bactericidal surfaces has been gaining significant attention. Proposed surface topography designs are often inspired by naturally occurring nanopatterns on insect wings that mechanically damage bacteria via membrane deformation. The stability of and the absence of chemicals in such surfaces support their facile and sustainable employment in avoiding surface-born pathogen transmission. Recently, the deflection of controllably nanofabricated pillar arrays has been shown to strongly affect bactericidal activity, with the limits of mechanical effectiveness of such structures remaining largely unexplored. Here, we examine the limits of softer, commonly used polymeric materials and investigate the interplay between pillar nanostructure sizing and flexibility for effective antibacterial functionality. A facile, scalable, UV nanoimprint lithography method was used to fabricate nanopillar array topographies of variable sizes and flexibilities. It was found that bacterial death on nanopillars in the range of diameters ≤100 nm and Young's moduli ≥1.3 GPa is increased by 3.5- to 5.6-fold, while thicker or softer pillars did not reduce bacterial viability. To further support our findings, we performed a finite element analysis of pillar deformation. It revealed that differences in the amount of stress exerted on bacterial membranes, generated from the stored elastic energy in flexible pillars, contribute to the observed bactericidal performance.

Introduction Percutaneous catheter-directed treatments have emerged at the last decade for the management of acute high- or intermediate-high-risk pulmonary embolism (PE). Good short-term efficacy and safety have been published, but there are limited data regarding medium- to long-term outcomes. Purpose This study aimed to evaluate 1-year all-cause mortality of acute high- and intermediate-high-risk PE patients (pts) treated with continuous aspiration mechanical thrombectomy. Methods Twenty-nine consecutive pts with acute central PE (mean age 67.2±14.4 years; 72.4% female; 24.1% active cancer; Charlson comorbidity index 4.5±2.1; 82.8% in class>III of original PESI score; 44.8% high-risk PE) were treated with the Indigo Mechanical Thrombectomy System (Penumbra, Inc) between 03/2018 and 03/2020. Clinical success was defined as improvement in hemodynamic and/or oxygenation parameters or pulmonary hypertension or right heart strain at 48 hours after intervention plus survival to hospital discharge. Data regarding severe adverse events potentially related to the procedure, in-hospital and 1-year all-cause mortality were collected. Results Clinical success was 75.9%, with a significant improvement in mean paO2/fiO2 ratio (+77.1±103.2; p Conclusions Aspiration thrombectomy for acute high- and intermediate-high-risk PE was feasible with a high clinical success rate. One-year all-cause mortality rate was elevated and predicted by high comorbidity index and de novo atrial fibrillation at admission. This data support the national expansion of this new PE treatment, but probably and as similar to other invasive techniques, we need to take into account comorbidities and avoid futility in multimorbidity pts. Funding Acknowledgement Type of funding sources: None.

Understanding the response of temperature to elevated atmospheric CO2 during past greenhouse intervals such as the Late Cretaceous can constrain hypotheses of expected future warming tied to the rise of modern atmospheric CO2 levels. Here we present new reconstructions of Gulf and Atlantic Coast coastal marine temperatures through the late Campanian (∼76–72 Ma) and Maastrichtian (72 Ma–66 Ma), as determined by carbonate clumped isotope analysis of marine bivalves and gastropods. We find temperatures in the range of ∼7–25 °C across multiple sites located between 31°N and 36°N paleolatitude, and cooler temperatures of ∼3–14 °C at sites around 39°N paleolatitude. Temperatures agree across a variety of taxa, indicating no appreciable organism-specific vital effects. The calculated paleotemperatures are very similar to modern marine temperatures at the same locations, despite the Late Cretaceous generally being considered a warmer interval. Clumped isotope temperatures are cooler than published temperatures from a nearby site measured using the TEX86 paleotemperature proxy, revealing a potential warm bias in TEX86 temperature estimates. The best agreement between clumped isotope and TEX86 temperatures is achieved when using the TEX 86 L calibration over TEX 86 H or BAYSPAR calibrations.

Use of the clumped isotope thermometer to decipher environments of dolomite formation has been inhibited by a lack of empirical data from dolomites formed at known temperatures. Calibrations for aragonite, calcite, siderite, and apatite indicate that a universal Δ 47 – temperature relationship may exist across all carbonate-bearing mineral phases. However, theoretical modeling and proposed acid fractionation differences have suggested that dolomites may have different Δ 47 values relative to calcites precipitated at the same temperature. To resolve this question, we analyzed five synthetic and four natural dolomites formed at known temperatures. These included synthetic dolomites grown in Mg-Ca-Cl solutions at temperatures of 200–250 °C, and natural samples constrained by fluid inclusion analyses (~ 70 °C), climate (~ 28 and ~ 27 °C), and deep ocean borehole temperature (~ 21 °C). When using calcite Δ 47 acid fractionation values, these data result in a calibration line that is statistically indistinguishable from other clumped isotope calibrations. At least with current precision, we find no evidence for a consistent dolomite Δ 47 offset. These results further support a universal calibration for carbonate clumped isotope thermometry and enable new investigations into conditions of dolomite formation.

The paths animals take while moving through their environments affect their likelihood of encountering food and other resources; thus, models of foraging behavior abound. To collect movement data appropriate for comparison with these models, we used time-lapse photography to track movements of a small, hardy, and easy-to-obtain organism, Aquilonastra anomala sea stars. We recorded the sea stars in a tank over many hours, with and without a food cue. With food present, they covered less distance, as predicted by theory; this strategy would allow them to remain near food. We then compared the paths of the sea stars to three common models of animal movement: Brownian motion, Lévy walks, and correlated random walks; we found that the sea stars' movements most closely resembled a correlated random walk. Additionally, we compared the search performance of models of Brownian motion, a Lévy walk, and a correlated random walk to that of a model based on the sea stars' movements. We found that the behavior of the modeled sea star walk was similar to that of the modeled correlated random walk and the Brownian motion model, but that the sea star walk was slightly more likely than the other walks to find targets at intermediate distances. While organisms are unlikely to follow an idealized random walk in all details, our data suggest that comparing the effectiveness of an organism's paths to those from theory can give insight into the organism's actual movement strategy. Finally, automated optical tracking of invertebrates proved feasible, and A. anomala was revealed to be a tractable, 2D-movement study system.

The Western Interior Seaway (WIS) was a shallow and expansive body of water that covered the central United States during the Late Cretaceous. Attempts to reconstruct temperatures in the seaway using the oxygen isotopic composition of biogenic carbonates have suffered from uncertainty in the oxygen isotopic composition of seawater (δ 18 O w ) in the semi-restricted basin. We present new reconstructed temperature and δ 18 O w data from marine and estuarine environments in the WIS and freshwater environments in WIS source rivers, derived from clumped isotope analyses of bivalve and gastropod shells. We find temperatures of 5–21 °C, δ 18 O w values below contemporaneous Gulf of Mexico marine sites, and a strong correlation between δ 18 O w and environmental setting. We propose that decreasing δ 18 O w values reflect decreasing salinity driven by an increasing contribution of continental runoff. Using a two-end-member salinity-δ 18 O w mixing model, we estimate salinities of 29–35 psu (practical salinity units) for the deep marine, 20–32 psu for the shallow marine, and 11–26 psu for the estuarine environments of the WIS. New climate model simulations agree with reconstructed temperatures and salinities and suggest the presence of salinity driven stratification within the seaway.

Carbonate clumped isotope paleothermometry is a promising method for paleoclimate reconstructions and understanding diagenetic processes, although clumped isotope compositions (measured as Δ47 values) can be altered by recrystallization and thermal resetting. Several studies have investigated the effects of deep burial and exhumation on Δ47 values; we present Δ47 values of samples from an ∼4500-m-long drill core from Andros Island, Bahamas, which represent the spectrum from shallow to deep burial conditions. These limestones and dolomites originally formed under near-surface temperature conditions, which are reflected by ∼27 °C Δ47 temperatures in samples buried to

Water resources management in Maui, Hawaii, remains a challenge due to uneven distribution of rainfall, water scarcity in populated areas, and an ill-defined hydrological system. Based on data collected in June 2014, Niu et al. (2017) suggested that noble gases in this rapid groundwater infiltration system record seasonality and may shed light on water sources, recharge locations, and groundwater flow paths. This study goes one step further by analyzing rainwater, basal and perched (springs) aquifer data collected in June 2014 and February 2016. It shows for the first time that both rain and spring water display sharp temporal variations which are related to either seasonal (summer/winter) variations or to the strong 2015–2016 El Nino year. These spring water temporal variations also suggest that perched aquifer groundwater is extremely young and likely unreliable as a long-term water supplier. In contrast, noble gas temporal variations are absent in the basal aquifer. This, in turn, is consistent with tritium derived groundwater ages on the order of a few decades for the basal aquifer. This study further demonstrates that Ne is an excellent candidate to estimate the source elevation of rain and thus, to distinguish between orographic and synoptic-scale rain. Water stable isotope data are also presented for both years with 2016 samples exhibiting greater deuterium excesses than those of 2014, an observation consistent with the drier 2015–2016 El Nino climate. Estimated water source elevations based on δ18O for rainwater display a positive correlation with those based on Ne concentrations.

Pursuit is a common behavior exhibited by animals chasing prey, competitors and potential mates. Because of their speed and maneuverability, dragonflies are frequently studied as a model system for biological pursuit. Most quantitative studies have focused on prey pursuits in captive environments. To determine whether a different pursuit strategy is used when chasing conspecifics of nearly equal speed and agility, we recorded 3D flight trajectories from nine territorial chases between male Erythemis simplicicollis dragonflies in natural field conditions. During chases, dragonflies used an interception strategy with an unusually high-magnitude gain (k=−10.03 s−1 horizontal; −8.86 s−1 vertical) and short time delay (τ=50 ms). The product kτ determines how aggressively a pursuer corrects course to achieve interception. Previous studies of prey pursuit have found kτ values close to −1/e (−0.37), the time-optimal value for achieving pursuit without overshooting. However, we found that dragonflies chasing conspecifics use more negative kτ (−0.50 horizontal; −0.44 vertical), resulting in pursuits with a high degree of overshooting (i.e. moving past the target and alternating position from side to side). We confirmed via simulation that the observed gain and delay produce overshooting. We propose that overshooting is an adaptive feature of conspecific chases that can be achieved with only slight modification of the strategy used for intercepting prey. Overshooting might help avoid potentially damaging collisions while exhibiting the pursuing animal's flight performance and competitive ability. Repeated close approaches might also evoke evasive responses from the other dragonfly, effectively herding the competitor out of the territory.

Meteoric diagenetic cements are ubiquitous throughout geologic history, affecting most carbonate exposures worldwide. They can often be difficult to interpret, as it is usually difficult to separate the influences of water δ18O and temperature on isotopic signals contained within the carbonate rock body. Despite this difficulty in interpretation, meteoric phreatic cements can potentially be a useful proxy material, as they form slowly in equilibrium at mean annual temperature and are not affected by any biogenic effects that can bias other proxy materials. We applied the mass-47 clumped isotope paleothermometer to Pleistocene and Holocene carbonates from Bermuda and Barbados in order to investigate the effects of meteoric diagenesis on Δ47 signals, and to determine their suitability as a paleotemperature proxy. Phreatic calcite cements are found to record the same temperatures as unaltered carbonate sediments, while any sample exhibiting vadose characteristics is biased towards unreasonably hot apparent formation temperatures. Burial heating and re-equilibration are not geologically viable explanations for the anomalously hot temperatures recorded in vadose cements, as neither Bermuda or Barbados has any burial history. Instead, it is likely that precipitation in the vadose zone occurs on timescales quicker than isotopic equilibrium can be achieved, driven by a combination of CO2 degassing and evaporation, which have been previously shown to cause problems in speleothems and pedogenic carbonates. We conclude by suggesting that meteoric phreatic calcites may be an ideal phase for paleotemperature reconstruction, as they accurately record mean annual temperatures and form under equilibrium conditions, while also being resistant to further mineral driven diagenesis. Vadose cements, and any sample likely affected by processes similar to vadose diagenesis, should be avoided for climate reconstructions using the mass-47 clumped isotope thermometer.

Rationale The clumped isotope paleothermometer, a new proxy widely applicable in studies of paleoclimate, tectonics, and paleontology, relates the abundance of doubly substituted isotopologues of carbonate-derived CO2 to the temperature of formation of the carbonate phase. As this technique becomes more widely used, more is discovered about the effects of everyday laboratory procedures on the clumped isotopic composition of CO2 gas. Methods Preparation of CO2 for clumped isotope analysis requires the removal of isobaric contaminants prior to measurement, achieved dynamically by passing the CO2 through a gas chromatography column using a helium carrier gas or cryogenically pumping CO2 through a static trap filled with Porapak™ Q (PPQ) material. The stable and clumped isotopic compositions of carbonate standards prepared at PPQ trap temperatures between −40°C and −10°C were measured by isotope ratio mass spectrometry to evaluate potential artifacts introduced by the static PPQ trap method. Results The stable isotopic composition of carbonates run at temperatures below −20°C was fractionated, despite achieving >99% retrieval of gas at temperatures as cold as −30°C. The δ13C and δ18O values decreased by ~0.01 and ~0.03 ‰/(°C below −20°C). The raw Δ47 values decreased by 0.003–0.005 ‰/(°C below −20°C), but the final reference-frame-corrected values (Δ47-RFAC) were unaffected as long as the carbonate samples and standard gases were prepared identically. Conclusions Preparing carbonate samples for clumped isotope analysis using a PPQ trap that is too cold can result in erroneous stable isotopic compositions. New and existing labs using the static PPQ trap cleaning procedure should determine the ideal PPQ trap temperature for their particular system through monitoring not only yield through the PPQ trap, but also stable isotopic composition at various PPQ trap temperatures. Copyright © 2015 John Wiley & Sons, Ltd.

This study uses stable noble gases' (He, Ne, Ar, Kr, Xe) volume fractions and isotopic ratios from Antrim Shale natural gas to assess compositional variability and vertical fluid migration within this reservoir, in addition to distinguishing between the presence of thermogenic versus biogenic methane. R/Ra values, where R is the measured 3He/4He ratio and Ra is the atmospheric value of 1.384 ± 0.013 × 10− 6, vary from 0.01 to 0.34 suggesting a largely dominant crustal 4He component with minor atmospheric and mantle contributions. Crustal 21Ne, 40Ar and 136Xe contributions are also present but the atmospheric component is largely dominant for these gases. Crustal contributions for 21Ne, 40Ar and 136Xe vary between 1.1% and 12.5%, between 0.7% and 19% and between 0.1% and 2.7%, respectively. A few samples present higher than atmospheric 20Ne/22Ne ratios pointing to the presence of a small mantle Ne component. High horizontal and vertical variability of noble gas signatures in the Antrim Shale are observed. These are mainly due to variable noble gas input from deep brines and, to a smaller extent, variable in-situ production within different layers of the Antrim Shale, in particular, the Lachine and Norwood members. Estimated 4He ages, considering external 4He input for Antrim Shale water, vary between 0.9 ka and 238.2 ka and match well for most samples with the timing of the major Wisconsin glaciation, suggesting that Antrim Shale water was influenced by glaciation-induced recharge. Consistency between measured and predicted 40Ar/36Ar ratios assuming Ar release temperatures ≥ 250 °C supports a thermogenic origin for most of the methane in these samples. This thermogenic methane is likely to originate at greater depths, either from the deeper portion of the Antrim Shale in the central portion of the Michigan Basin or from deeper formations given that the thermal maturity of the Antrim Shale in the study area is rather low.

RATIONALE: Mass-47 CO2 clumped isotope thermometry requires relatively large (similar to 20 mg) samples of carbonate minerals due to detection limits and shot noise in gas source isotope ratio mass spectrometry (IRMS). However, it is unreasonable to assume that natural geologic materials are homogenous on the scale required for sampling. We show that sample heterogeneities can cause offsets from equilibrium Delta(47) values that are controlled solely by end member mixing and are independent of equilibrium temperatures.METHODS: A numerical model was built to simulate and quantify the effects of end member mixing on Delta(47). The model was run in multiple possible configurations to produce a dataset of mixing effects. We verified that the model accurately simulated real phenomena by comparing two artificial laboratory mixtures measured using IRMS to model output.RESULTS: Mixing effects were found to be dependent on end member isotopic composition in delta C-13 and delta O-18 values, and independent of end member Delta(47) values. Both positive and negative offsets from equilibrium Delta(47) can occur, and the sign is dependent on the interaction between end member isotopic compositions. The overall magnitude of mixing offsets is controlled by the amount of variability within a sample; the larger the disparity between end member compositions, the larger the mixing offset.CONCLUSIONS: Samples varying by less than 2 % in both delta C-13 and delta O-18 values have mixing offsets below current IRMS detection limits. We recommend the use of isotopic subsampling for delta C-13 and delta O-18 values to determine sample heterogeneity, and to evaluate any potential mixing effects in samples suspected of being heterogonous. Copyright (C) 2015 John Wiley & Sons, Ltd.

3He and 4He concentrations in excess of those in water in solubility equilibrium with the atmosphere by up to two and three orders of magnitude are observed in the shallow Glacial Drift and Saginaw aquifers in the Michigan Basin. A simplified He transport model shows that in situ production is negligible and that most He excesses have a source external to the aquifer. Simulated results show that 3He and 4He fluxes entering the bottom of the Saginaw aquifer are 7.5 × 10−14 and 6.1 × 10−7 cm3STPcm−2 yr−1, both of which are lower than fluxes entering the underlying Marshall aquifer, 1.0 × 10−13 and 1.6 × 10−6 cm3STPcm−2 yr−1 for 3He and 4He, respectively. In contrast, He fluxes entering the Saginaw aquifer are higher than fluxes entering the overlying Glacial Drift aquifer of 5.2 × 10−14 and 1.5 × 10−7 cm3STPcm−2 yr−1 for 3He and 4He, respectively. The unusually high He fluxes and their decreasing values from the lower Marshall to the upper Glacial Drift aquifer strongly suggest the presence of an upward cross-formational flow, with increasing He dilution toward the surface by recharge water. These fluxes are either comparable to or far greater than He fluxes in deeper aquifers around the world. Model simulations also suggest an exponential decrease in the horizontal groundwater velocity with recharge distance. Horizontal velocities vary from 13 to 2 myr−1 for the Saginaw aquifer and from 18 to 6 myr−1 for the Marshall aquifer. The highly permeable Glacial Drift aquifer displays a greater velocity range, from 250 to 5 myr−1. While Saginaw 4He ages estimated based on the simulated velocity field display an overall agreement with 14C ages, 14C and 4He ages in the Glacial Drift and Marshall aquifers deviate significantly, possibly due to simplifications introduced in the He transport model leading to calculation of first-order approximation He ages and high uncertainties in Glacial Drift 14C ages.

An essential procedure to increase the analytical efficiency of Delta(47) measurements requires raising the temperature of phosphoric acid digestion for carbonate materials. This temperature change introduces a fractionation offset in Delta(47) that must be accounted for prior to calculation of temperatures of carbonate formation and to allow interlaboratory comparison of results. We measured the phosphoric acid fractionation factor relative to reaction at 25 degrees C for calcite, aragonite, and dolomite across a temperature range from 25 to 90 degrees C. Significantly, all three minerals behave similarly during phosphoric acid digestion, allowing for a single temperature dependent acid fractionation relationship:1000 ln infinity CO2(Acid)-Delta(47) = (0.022434 +/- 0.001490) * 10(6)/T-2 - (0. 2524 +/- 0: 0168)where a is the phosphoric acid fractionation factor, and T is in degrees Kelvin. Mineralogical or isotopic compositional effects on the fractionation factorwere not observed, suggesting that this acid fractionation factor may be valid for all carbonate minerals. We also present inorganic temperature calibrations for both calcite and aragonite at low temperatures ( 5-70 degrees C) and find them to agree with prior published data. Using the new acid fractionation factor, published Delta(47)-temperature calibrations are recalculated. This analysis confirms a statistically significant Delta(47)-temperature calibration difference between data analyzed at 25 degrees C versus higher temperatures. The origin of the discrepancy remains unknown, but it appears that the acid fractionation factor is not the cause. (C) 2015 Elsevier B.V. All rights reserved.

Optic pit is a congenital anomaly with malformation similar to coloboma of the optic disc. The cause of optic pit maculopathy is controversial. We used high resolution OCT to investigate changes in the vitreoretinal and vitreopapillary transition within optic pit eyes.The vitreoretinal and vitreo-papillary transition of 12 eyes was accurately analyzed using SD-OCT. We registered the following criteria: liquefaction of prepapillary vitreous, papillary vitreous traction, discontinuity within the hyaloid cortex and communication spaces between pit and retinal edema.Communication gaps between pit and retinal edema were identified in 8 eyes. 4 eyes had a papillary vitreous traction. 4 showed a discontinuity in the hyaloid cortex. 2 of the 12 patients showed no maculopathy in SD-OCT. Those patients had an adjacent papillary vitreous without prepapillary liquefaction. However all eyes showed vitreous liquefaction at some stage premacullary or prepapillary.Yet the cause of optic pit maculopathy is not clearly understood. High resolution OCT imaging provides a very detailed assessment of the vitreoretinal transition prepapillary and premacullary, however with limited penetration depth and analyzation of deeper lying structures. Our observations suggest that prepapillary liquefaction and pressure gradients within cerebrospinal and intraokular pressure could be key factors.

Resume Introduction Les statines ou inhibiteurs de la 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGCR) font partie des traitements les plus prescrits en France. Ils sont par ailleurs bien connus pour etre a l’origine d’intolerances musculaires de severite variable. Recemment, ils ont ete impliques dans la survenue de myopathies inflammatoires acquises liees a la presence d’anticorps anti-HMGCR. Cette nouvelle myopathie toxique reste mal connue par des cliniciens. Observation Nous rapportons l’observation d’une patiente de 61 ans, traitee depuis de nombreuses annees par une statine, qui presentait une myopathie invalidante des quatre membres d’evolution rapidement defavorable malgre l’arret du traitement. L’histoire clinique, les investigations paracliniques et notamment le dosage des anticorps anti-HMGCR permettaient de retenir le diagnostic de myopathie necrosante auto-immune a anticorps anti-HMGCR et d’initier un traitement immunosuppresseur efficace. Conclusion Un traitement par une statine peut demasquer ou etre a l’origine d’une authentique myopathie necrosante auto-immune en rapport avec la presence d’anticorps anti-HMGCR. Un traitement immunosuppresseur est necessaire et rendu licite par la demonstration du caractere auto-immun de l’affection depuis l’identification des anticorps anti-HMGCR qui peuvent desormais etre doses en routine.

Significant atmospheric noble gas excesses in aquifer systems have systematically been linked to increased hydrostatic pressure, either due to increased water table levels or due to the development of ice cover. Measured noble gases (Ne, Ar, Kr, and Xe) in the shallow Saginaw aquifer in the Michigan Basin display both moderate (∼20–60% Ne excess) and large (∼80−>120% Ne excess) excesses of atmospheric noble gases with respect to air saturated water for modern recharge conditions. All large atmospheric noble gas excesses are located in the main discharge area of the Michigan Basin, in the Saginaw Lowlands region. Here, through a step-by-step analysis, we first show that large atmospheric noble gas excesses in the Saginaw aquifer do not result from increased hydrostatic pressure but, instead, are the result of vertical transport of atmospheric noble gases that are believed to have escaped from deep Michigan Basin brines following a past thermal event of mantle origin. Subsequently, we show that the atmospheric noble gas pattern of the entire Michigan Basin strata appears to result from two distinct end-members: (a) an end-member represented by the deepest, most depleted brines from which most of the atmospheric noble gases escaped; and (b) an end-member with excess atmospheric noble gas values above those displayed by the Saginaw samples. The latter is unconstrained due to the dilution effect exerted by recharge water. Using a Rayleigh distillation model we further show that the greater enrichment of lighter relative to heavier noble gases in the Saginaw aquifer in the Saginaw Lowlands area is compatible with either diffusion or solubility related mechanisms. These findings reinforce the notion that a past thermal event is indeed responsible for the atmospheric noble gas excesses found in the Saginaw aquifer in the Saginaw Lowlands area. They are also consistent with and reinforce previous findings with respect to the occurrence of a thermal event of mantle origin in the Michigan Basin.

[1] This work represents the first comprehensive noble gas study in rainwater. It was carried out in southeast Michigan. Results show that all rainwater samples are in disequilibrium with surface conditions. Two noble gas patterns are identified. The first one, associated with low-pressure systems, presence of fog and light rainfall, displays a relative Ar enrichment together with Ne, Kr, and Xe depletion. The second one, associated with the passage of frontal systems, displays a mass-dependent depletion pattern. Precipitation is characterized by thunderstorms, heavy rainfall, and high cloud ceiling heights. A diffusion mass-transfer model suggests that noble gas patterns originate from ice. Complete re-equilibration with surface conditions should occur within hours. For the first time, this study establishes a direct correlation between the noble gas composition in rainwater and weather patterns and highlights their potential to identify timing and location of recharge in shallow aquifer systems where infiltration is rapid.

[1] Quantitative paleoelevation histories can help explain both why and how widespread Cenozoic extension occurred in the Basin and Range Province of western North America. We present new estimates of preextensional paleoelevations for the northern and central Basin and Range using clumped isotope (Δ47) thermometry of lacustrine carbonates collected from each region. Comparison of carbonate Δ47-derived mean annual air temperature (MAAT) estimates (~16°C–20°C) for the Late Cretaceous–Eocene Sheep Pass basin of east central Nevada with published MAAT estimates for the Eocene, coastal northern Sierra Nevada (~20°C–25°C), suggests that the early Paleogene Sheep Pass basin had a paleoelevation of ≤2 km. Such a modest paleoelevation suggests that either (1) the proto–northern Basin and Range did not attain maximum paleoelevations of 3–4 km until the late Eocene–early Oligocene; or (2) the Sheep Pass basin was a local, high-relief (>1 km) setting contained within a >3 km orogenic highland (“Nevadaplano”). Similarity of Δ47-derived MAAT estimates (~17°C–24°C) for carbonates from the central Basin and Range and the near–sea level southern Sierra Nevada Bena basin indicate that middle Miocene paleoelevations in the Death Valley region were ≤1.5 km. These fairly low paleoelevations are incompatible with preextensional crustal thicknesses >52 km and indicate that mean elevation change was minor (≤500 m) and lithospheric mass was not conserved during >100% Neogene extension of the central Basin and Range, but was instead likely compensated by synextensional magmatic additions to the crust.

Geochemical and modeling studies suggest that the transition from the “greenhouse” state of the Late Eocene to the “icehouse” conditions of the Oligocene 34–33.5 Ma was triggered by a reduction of atmospheric p CO 2 that enabled the rapid buildup of a permanent ice sheet on the Antarctic continent. Marine records show that the drop in p CO 2 during this interval was accompanied by a significant decline in high-latitude sea surface and deep ocean temperature and enhanced seasonality in middle and high latitudes. However, terrestrial records of this climate transition show heterogeneous responses to changing p CO 2 and ocean temperatures, with some records showing a significant time lag in the temperature response to declining p CO 2 . We measured the Δ 47 of aragonite shells of the freshwater gastropod Viviparus lentus from the Solent Group, Hampshire Basin, United Kingdom, to reconstruct terrestrial temperature and hydrologic change in the North Atlantic region during the Eocene–Oligocene transition. Our data show a decrease in growing-season surface water temperatures (∼10 °C) during the Eocene–Oligocene transition, corresponding to an average decrease in mean annual air temperature of ∼4–6 °C from the Late Eocene to Early Oligocene. The magnitude of cooling is similar to observed decreases in North Atlantic sea surface temperature over this interval and occurs during major glacial expansion. This suggests a close linkage between atmospheric carbon dioxide concentrations, Northern Hemisphere temperature, and expansion of the Antarctic ice sheets.

The case of a 77-year-old woman with trauma after a fall is reported. On clinical examination, an avulsion injury was found in the left eye with dual optic nerve dissection. An INR of 3.3 was determined in a perioperative blood sample. The given conditions forced the rare but urgent indication for primary enucleation with hemostasis. Oral anticoagulation presented perioperative high risk, especially due to the potential risk of bleeding from the ophthalmic artery.

The warm climate of Bermuda today is modulated by the nearby presence of the Gulf Stream current. However, iceberg scours in the Florida Strait and the presence of ice-rafted debris in Bermuda Rise sediments indicate that, during the last deglaciation, icebergs discharged from the Laurentide Ice Sheet traveled as far south as subtropical latitudes. We present evidence that an event of similar magnitude affected the subtropics during the Last Interglacial, potentially due to melting of the Greenland Ice Sheet. Using the clumped isotope paleothermometer, we found temperatures similar to 10 degrees C colder and seawater delta O-18 values similar to 2% lower than modern in Last Interglacial Cittarium pica shells from Grape Bay, Bermuda. In contrast, Last Interglacial shells from Rocky Bay, Bermuda, record temperatures only slightly colder and seawater delta O-18 values similar to modern, likely representing more typical Last Interglacial conditions in Bermuda outside of a meltwater event. The significantly colder ocean temperatures observed in Grape Bay samples illustrate the extreme sensitivity of Bermudian climate to broad-scale ocean circulation changes. They indicate routine meltwater transport in the North Atlantic to near-equatorial latitudes, which would likely have resulted in disruption of the Atlantic Meridional Overturning Circulation. These data demonstrate that future melting of the Greenland Ice Sheet, a potential source of the Last Interglacial meltwater event, could have dramatic climate effects outside of the high latitudes.

The Steptoean positive carbon isotope excursion (SPICE) marks a global oceanographic event that confirms intercontinental correlations between different biogeographic realms based on agnostids and other blue-water trilobites. The SPICE excursion is documented from sections in Laurentia, Kazakhstan, China, and Australia where it begins with the mass extinction at the base of the Pterocephaliid Biomere (Steptoean Stage) in Laurentia and at coeval extinction horizons in Gondwana and periGondwana terranes. The peak of SPICE (+ 5%0) coincided with a time of maximum regression in Laurentia. SPICE is similar in this regard to excursions that coincide with glacio-eustatic falls, such as in the Late Ordovician. A plausible scenario involves the transformation of ocean circulation between two states, which led to enhanced coastal upwelling and benthic extinctions. The lack of evidence for glaciation indicates that the coeval sea level fall (Sauk II-Sauk III event) resulted from tectonic or hydrologic changes that remain poorly understood at this time. (C) 2000 Elsevier Science B.V.

Robust isotopic reconstructions of climate, elevation, and biology require a reasonable capture of the range of isotopic variability across a paleolandscape. Here, we illustrate how integrating multiple proxies derived from a variety of paleoenvironments aids in this effort. We determined d 18O and d13C values from lake and soil carbonates, unionid shells, gar scales, and crocodile teeth from multiple depositional environments (lakes, soils, ponds, streams, and large rivers) spanning a 300 km proximal-to-distal transect within the Late Cretaceous foreland basin of Montana. Two major patterns emerge. First, quiet water environments display higher d 18O and lower d13C values than large rivers, which indicates greater input from local precipitation compared to highaltitude runoff, and a relatively larger contribution of degraded vegetative matter to the dissolved inorganic carbon load. Second, proxies with seasonal biases toward late spring and summer growth display lower d18O and d13C values in the basin proximal setting compared to the distal coastal setting, which is linked to the rainout history of vapor masses moving across the foreland basin. Overall these isotopic patterns mirror those in modern catchments, support hypotheses of monsoonal rainfall within the basin, and suggest a hypsometric mean elevation of ,2.6 km within the Sevier orogenic belt. Furthermore, our results indicate a potential to subdivide freshwater paleoecosystems to refine paleobiologic studies of habitat preference and migration patterns.

Resume But de l’etude La technique Matrix Assisted Laser Desorption Ionisation Time Of Flight (MALDI-TOF) est en plein essor. Elle permet d’obtenir un spectre des proteines ribosomales et de membranes en fonction de leur poids, ce spectre compare a une base de donnees permet d’identifier les microorganismes. Le laboratoire de microbiologie du centre hospitalier de Mulhouse a fait l’acquisition de cette technique en mai 2009. Methode Nous avons utilise le spectrometre de masse Axima ® (Shimatzu) couple au logiciel Saramis ® (Anagnostec), l’integration a l’informatique du laboratoire se faisant via le logiciel SirWeb ® (societe I2A). La majorite des souches isolees dans le laboratoire a ete analysee en spectrometrie. Resultats La technique a rapidement ete acquise par l’ensemble du personnel du laboratoire. Pendant cette etude, 98,8 % des isolats analyses ont ete identifies jusqu’a l’espece, voire la sous espece. Le recours a une autre technique, essentiellement la biologie moleculaire a rarement ete necessaire, ce recours etant limite aux isolats cliniquement significatifs. L’utilisation de la spectrometrie de masse permet une identification rapide et precise de la majorite des microorganismes rencontres dans notre activite. La base Saramis comprend des especes rares et d’identification fastidieuse par les techniques classiques, certaines lacunes sont a combler. Les superspectres, specifiques de la base Saramis ® permettent une validation technique tres fiable. Conclusion La spectrometrie de masse s’est donc parfaitement integree a notre activite de routine, l’identification et l’antibiogramme se faisant plus souvent a partir d’une seule colonie. La coloration de Gram et les tests simples gardent tout leur interet.

Resume But de l’etude Le laboratoire de microbiologie de l’hopital de Mulhouse s’est equipe d’un systeme VersaTREK de detection de croissance automatique des mycobacteries, developpe par la societe TREK Instruments aux Etats-Unis, distribue en France par Biocentric. Nous evaluons ce systeme sur les prelevements analyses d’avril 2009 a mars 2010. Methode Le systeme VersaTREK associe un milieu de culture liquide, un supplement de croissance et pour les echantillons potentiellement contamines, un supplement antibiotique. La technologie se base sur la detection des modifications de pression dans la partie superieure d’un flacon ferme en surveillant les modifications dans la production ou la consommation de gaz dues a la croissance microbienne. L’incubation est de 42 jours. Un tube de coletsos est ensemence en parallele. Le systeme a ete valide pour tous types de prelevements et permet la realisation d’un antibiogramme pour les antituberculeux de premiere intention. Resultats Le delai de detection est plus court par rapport a la culture en milieu solide. Le delai moyen de detection des positifs est de 19,1 et 35,6 jours respectivement pour le milieu liquide et le milieu solide. Des prelevements sont uniquement positifs en milieu liquide (ganglions). L’antibiogramme est obtenu rapidement (six et 13 jours) a partir d’une culture positive. Les techniques d’identification par biologie moleculaire peuvent etre realisees directement a partir d’un echantillon preleve sur un flacon positif. Conclusion Ce systeme permet un diagnostic plus rapide et est une alternative aux autres automates de culture en milieu liquide existants.

Calcite Mg/Ca is usually assumed to vary linearly with solution Mg/Ca, that a constant partition coefficient describes the relationship between these two ratios. Numerous published empirical datasets suggests that this relationship is better described by a power function. We provide a compilation of these literature data for biotic and abiotic calcite in the form of Calcite Mg/Ca = F(Solution Mg/Ca)H, where F and H are empirically determined fitting parameters describing the slope and deviation from linearity, respectively, of the function. This is equivalent to Freundlich sorption behavior controlling Mg incorporation in calcite. Using a power function, instead of a partition coefficient, lowers Phanerozoic seawater Mg/Ca estimates based on echinoderm skeletal material by, on average, 0.5 mol/mol from previous estimates. These functions can also be used to model the primary skeletal calcite Mg/Ca of numerous calcite phases through geologic time. Such modeling suggests that the Mg/Ca of all calcite precipitated from seawater has varied through the Phanerozoic in response to changing seawater Mg/Ca and that the overall range in Mg/Ca measured among various calcite phases would be greatest when seawater Mg/Ca was also high (e.g., “aragonite seas”) and lowest when seawater Mg/Ca was low (e.g., “calcite seas”). It follows that, during times of “calcite seas” when the seawater Mg/Ca is presumed to have been lower, deposition of calcite with low Mg contents would have resulted in a depressed drive for diagenetic stabilization of shelfal carbonate and, in turn, lead to greater preservation of crystal and skeletal microfabrics and primary chemistries in biotic and abiotic calcites.

The Palaeocene–Eocene thermal maximum (PETM) is a well-known abrupt warming that occurred about 55.8 million years ago and is usually thought to have been caused by a large release of greenhouse gases, probably from methane hydrates, as recorded in a large carbon isotope excursion. Ross Secord and colleagues have used isotopic analysis of mammal teeth from the Bighorn Basin, Wyoming, to show that continental warming of about 5 °C preceded the isotopic excursion. The PETM therefore seems to have been caused by at least two separate warming events, each forced by different processes. The Palaeocene–Eocene thermal maximum (PETM) is a well-known abrupt warming that occurred at about 55.8 Myr ago and is usually thought to have been caused by a large release of greenhouse gases, as recorded in a large carbon isotope excursion. Yet some marine evidence suggests that in fact the warming came first. Here it is shown that continental warming of about 5 °C preceded the excursion in the Bighorn Basin, Wyoming. Thus the PETM seems to have been caused by at least two separate warming events. Marine and continental records1 show an abrupt negative shift in carbon isotope values at ∼55.8 Myr ago. This carbon isotope excursion (CIE) is consistent with the release of a massive amount of isotopically light carbon into the atmosphere and was associated with a dramatic rise in global temperatures termed the Palaeocene–Eocene thermal maximum (PETM). Greenhouse gases released during the CIE, probably including methane, have often been considered the main cause of PETM warming. However, some evidence from the marine record suggests that warming directly preceded the CIE2,3,4, raising the possibility that the CIE and PETM may have been linked to earlier warming with different origins. Yet pre-CIE warming is still uncertain. Disentangling the sequence of events before and during the CIE and PETM is important for understanding the causes of, and Earth system responses to, abrupt climate change. Here we show that continental warming of about 5 °C preceded the CIE in the Bighorn Basin, Wyoming. Our evidence, based on oxygen isotopes in mammal teeth (which reflect temperature-sensitive fractionation processes) and other proxies, reveals a marked temperature increase directly below the CIE, and again in the CIE. Pre-CIE warming is also supported by a negative amplification of δ13C values in soil carbonates below the CIE. Our results suggest that at least two sources of warming—the earlier of which is unlikely to have been methane—contributed to the PETM.

87 Sr/ 86 Sr measurements were carried out on samples of various macrofossil taxa recovered from the SMS AND-2A core with the main goal of improving age control of the core, and provide insight on marine climate at the time of carbonate precipitation. Shell material was carefully screened using cathodoluminescence (CL) to discern optimum areas for microdrilling. Powders thus obtained were in addition analyzed for Ca, Mg, Sr, Mn, and Fe contents to further evaluate the possibility of diagenetic alteration of the skeletal carbonate before measuring their Sr isotope compositions. Bivalves turned out to be the best candidates for isotopic determinations. Unaltered calcitic bivalves produced reliable 87 Sr/ 86 Sr age ranges. Aragonitic material, on the other hand, produced less radiogenic 87 Sr/ 86 Sr than anticipated, an unexpected result. Preliminary oxygen isotope determinations in calcite samples confirm contrasting marine climate conditions between the late Early Miocene (16.5–16.0 Ma), and the early Late Miocene (~ 11 Ma).

Basalts from continental flood basalts (CFBs) and intraplate or hotspot ocean islands are found to have distinct geochemical signatures. This diversity in composition is generally believed to result from the upwelling plume entraining overlying reservoirs of shallow and intermediate depth mantle material during its ascent from the deep mantle. Here we present laboratory experiments and numerical model calculations which clarify that — for a strongly temperature dependent viscosity like that of the mantle — a rising plume head should be expected to bring up a surrounding sheath of deep mantle from its source region. Mixing between the central core of the plume and this sheath produces the whorl-like structures noted in previous studies where they were typically attributed to thermal entrainment of surrounding ambient mantle, but this is mainly the product of intermixing between neighboring parts of the plume's deep source material. These results imply that the popular idea that mantle plumes should typically mix small fractions of deep ‘primitive’ mantle material with much larger fractions of shallower depleted mantle needs to be critically reexamined.

The Laboratory Proficiency Testing Program tests and evaluates proficiency of clinical laboratories in Ontario, Canada. The programme began in 1974; testing of reticulocyte counts was added in 1982. From the beginning, the goal of the programme has been to ensure that the quality of practice in Ontario laboratories facilitates good quality patient care. Testing of indirect counting methods for reticulocytes is accomplished by the distribution of stained blood films. Performance is expressed in terms of accuracy and precision. Proficiency is assessed by comparing submitted results to an all-methods' mean and result reliability by observing the coefficient of variation (CV) of the cohort. The quality of the results vary neither with the manual counting system used nor the type of laboratory. The CV commonly ranges from 25 to 30%, and this lack of accuracy appears to be inherent in the technology of manual reticulocyte counting. We conclude that manual reticulocyte counting is technologically obsolete but may be of clinical value if used in a qualitative fashion. It should probably be replaced by an automated method.

A high-resolution record of Eocene paleotemperature variation is preserved within the high southern latitude, marine shelf succession of the La Meseta Formation on Seymour Island, off the NE side of the Antarctic Peninsula. 87 Sr/ 86 Sr ratios of bivalve shell carbonate indicate that the La Meseta Formation spans virtually the entire Eocene, and suggest the presence of an early middle Eocene unconformity. Paleoclimatic and paleoceanographic inferences are based on the stable oxygen and carbon isotope values of two genera of bivalves collected with a high degree of stratigraphic resolution within the formation, and with multiple replicate samples from each horizon. δ 18 O data indicate roughly 10 °C of cooling from the early Eocene climatic optimum (~15 °C) through the end of the Eocene (minimum ~5 °C), much of which took place in two comparatively short intervals at ca. 52 and ca. 41 Ma. Many features of the isotope curves generated from this Eocene shelf section are apparent in δ 18 O and δ 13 C data from the Southern and global oceans, including warm intervals that likely correspond to the early and middle Eocene climatic optima (EECO and MECO). A rapid middle Eocene shift to much more positive values is the most signifi cant in the section and refl ects a drop to universally cooler temperatures in the late middle and late Eocene that might also be associated with a short-lived glacial advance. However, even using a somewhat depleted value for δ 18 O of seawater in the Antarctic peninsular region, average Seymour Island shelf-water paleotemperatures did not reach freezing before the end of the Eocene. δ 13 C data similarly refl ect the documented middle Eocene surface ocean enrichment followed by more negative values, but depletion is much more pronounced on Seymour Island and persists for the remainder of the Eocene, suggesting a combination of upwelling, metabolic effects, and/or atypical carbon cycling on the shelf in this region. Isotope data capture information about changes in the paleoenvironment that also had consequences for the biota, as published paleontological records document marked change in the nature of terrestrial and marine biota at this time. The fact that middle Eocene cooling and biotic turnover in the Peninsular region correspond well in time to the proposed initial opening of Drake Passage suggests that the formation of gateways, in addition to changes in pCO 2 , had signifi cant consequences for the Earth’s climate system during the Paleogene.

It has been proposed that Phanerozoic variation in the Mg/Ca ratio of seawater has resulted in variation in the primary mineralogies of shallow-water carbonates between aragonite- and calcite-dominated "seas." To test this hypothesis, this study estimates the Mississippian oceanic Mg/Ca and Sr/Ca ratios from the composition of marine carbonate cements and crinoidal carbonate, both of which have been suggested to faithfully record seawater chemistry. The early Mississippian (Tournaisian–Visean) Muleshoe Mound (Lake Valley Fm, Alamogordo, NM, U.S.A.) lends itself well to this endeavor because it contains abundant crinoids and marine carbonate cement. Stable isotope and elemental analyses, as well as cathodoluminescence characteristics, elucidate the diagenetic history of the bioherm and identify the least diagenetically altered materials for reconstruction of paleoseawater chemistry. Isotopic analyses document two diagenetic trends, one meteoric and one burial, diverging from values similar to literature estimates of Mississippian marine calcite (−1.5‰ δ18O, +4.5‰ δ13C). The burial diagenetic trend follows from this origin to more negative oxygen values (−7‰ δ18O, +3‰ δ13C). The meteoric diagenetic trend is defined by a meteoric calcite line at ~ −3‰ δ18O. Similarity of non-luminescent marine cement and non-luminescent crinoid isotopic and elemental compositions suggests that crinoidal carbonate was completely replaced by cement in the marine environment. Average elemental ratios for least altered marine cements are: Mg/Ca = 11 mmol/mol; Sr/Ca = 0.2 mmol/mol; Mn/Ca = 0.2 mmol/mol, and Fe/Ca = 0.4 mmol/mol. Early Mississippian seawater is estimated to have had a Mg/Ca ratio of ~ 0.2–0.3 mol/mol. This Mg/Ca ratio is compatible with the early Mississippian being an interval of "calcite sea" conditions and compares well with the Devonian estimate from marine cements, 0.5, though it is 5–10 times lower than estimates from mass balance modeling. The Sr/Ca for early Mississippian seawater was between 0.5 and 0.9 mmol/mol, which is much lower than previous estimates of ~ 6 mmol/mol from brachiopod calcite and argues for the development of a Sr sink (aragonite?) in the latest Devonian to earliest Mississippian.

Oxygen and carbon isotope ratios were measured on belemnites, planktonic foraminifera, and benthic foraminifera collected from Late Cretaceous sediments on Seymour Island, Antarctic Peninsula, to compare the relative depth habitats of these organisms and to provide insight on temperature seasonality at high southern latitudes near the end of the Cretaceous. Average δ18O and δ13C values of the belemnite Dimitobelus seymouriensis overlap with those of benthic foraminifera; these values are significantly different (p < 0.01) from isotopic compositions recorded by planktonic foraminifera. This comparison shows that D. seymouriensis likely inhabited waters below the surface summer mixed layer of the outer shelf. These results suggest that average δ18O of D. seymouriensis is a good indicator of intermediate-to-deep-shelf water conditions, which in this locality is a good approximation for pelagic water temperatures in the Southern Ocean. Measurements of δ18O on high-resolution samples across belemnite ...

Background: The clinical relevance of RT-PCR positivity for melanoma markers in the sentinel node remains controversial. Our purpose was to determine whether patients with a histologically negative but RT-PCR positive node were at an increased risk for recurrence than their RT-PCR negative counterparts. Methods: Thirty-nine adult patients underwent sentinel node biopsies for melanoma between 1998 and 2000. Each sentinel node was bivalved. Half was serially sectioned and examined by routine hematoxylin and eosin (HE S100, HMB-45, melanA, and tyrosinase). The other half was analyzed by a nested RT-PCR assay for tyrosinase. Results: Patients were followed for recurrence with a mean follow-up of 71.1 months. The odds ratio of recurrence for RT-PCR positive versus RT-PCR negative patients was 1.39 (0.34, 5.62; p ¼0.73). Within the histology negative subgroups, the risk of recurrence in the RT-PCR positive group (26.7%) was not significantly different from the risk of recurrence in the RT-PCR negative group (22.2%) (p ¼0.33 chi-squared). RT-PCR of the sentinel node was not a predictor for recurrence on multivariate analysis (p ¼0.65). Conclusion: Sentinel node RT-PCR positivity did not risk stratify histologically negative melanoma patients beyond routine pathologic examination in this series. J. Surg. Oncol. 2007;95:546–554. 2007 Wiley-Liss, Inc.

Biomaterials play a major role in interventional medicine and surgery. However, the development of biomaterials is still in its early phases in spite of the huge progress made within the last decades. On the one hand, this is because our knowledge of the molecular and cellular processes associated with biomaterials is still increasing exponentially. On the other hand, a wide variety of advanced materials with highly interesting properties is being developed currently. This review provides a short introduction into the variety of materials in use as well as their application in interventional medicine and surgery. Also the importance of biomaterials for tissue engineering in the field of regenerative medicine and the functionalisation of biomaterials, including sterilisation methods are discussed. For the future, an even broader interdisciplinary scientific collaboration is necessary in order to develop novel biomaterials and facilitate their translation into clinical practice.

The clumped isotope paleothermometer, a new proxy widely applicable in studies of paleoclimate, tectonics, and paleontology, relates the abundance of doubly substituted isotopologues of carbonate-derived CO2 to the temperature of formation of the carbonate phase. As this technique becomes more widely used, more is discovered about the effects of everyday laboratory procedures on the clumped isotopic composition of CO2 gas.Preparation of CO2 for clumped isotope analysis requires the removal of isobaric contaminants prior to measurement, achieved dynamically by passing the CO2 through a gas chromatography column using a helium carrier gas or cryogenically pumping CO2 through a static trap filled with Porapak™ Q (PPQ) material. The stable and clumped isotopic compositions of carbonate standards prepared at PPQ trap temperatures between -40°C and -10°C were measured by isotope ratio mass spectrometry to evaluate potential artifacts introduced by the static PPQ trap method.The stable isotopic composition of carbonates run at temperatures below -20°C was fractionated, despite achieving99% retrieval of gas at temperatures as cold as -30°C. The δ(13)C and δ(18)O values decreased by ~0.01 and ~0.03 ‰/(°C below -20°C). The raw Δ47 values decreased by 0.003-0.005 ‰/(°C below -20°C), but the final reference-frame-corrected values (Δ47-RFAC ) were unaffected as long as the carbonate samples and standard gases were prepared identically.Preparing carbonate samples for clumped isotope analysis using a PPQ trap that is too cold can result in erroneous stable isotopic compositions. New and existing labs using the static PPQ trap cleaning procedure should determine the ideal PPQ trap temperature for their particular system through monitoring not only yield through the PPQ trap, but also stable isotopic composition at various PPQ trap temperatures.