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Capturing and utilizing CO2 as carbon feedstock for chemicals, fuels, or polymers is frequently discussed to replace fossil carbon and thereby help mitigate climate change. Emission reductions by Carbon Capture and Utilization (CCU) depend strongly on the choice of the CO2 source because CO2 sources differ in CO2 concentration and the resulting energy demand for capture. From a climate-change perspective, CO2 should be captured at the CO2 source with the lowest CO2 emissions from capture. However, reported carbon footprints differ widely for CO2 captured, from strongly negative to strongly positive for the same source. The differences are due to methodological ambiguity in the treatment of multifunctionality in current assessment practice. This paper reviews methodological approaches for determining the carbon footprint of captured CO2 as carbon feedstock, and shows why some approaches lead to suboptimal choices of CO2 sources and that increased consistency in life cycle assessment (LCA) studies on CCU is needed. Based on strict application of Life Cycle Assessment (LCA) standards and guidelines, it is shown that substitution should be applied to avoid suboptimal choices of CO2 sources. The resulting methodological recommendations are applied to estimate the carbon footprint of feedstock CO2 for current CO2 sources in Europe and for future CO2 sources in a scenario for a low carbon economy. For all CO2 sources, the cradle-to-gate footprint of captured CO2 is negative ranging from -0.95 to -0.59 kg CO2 eq. per kg of feedstock CO2 today and from -0.99 to -0.98 kg CO2 eq. in a low carbon economy. The carbon footprints of different CO2 sources differ mainly due to their energy demands. The presented assessment method and the carbon footprints of the CO2 feedstocks CO2 provide the basis for future assessments of carbon capture and utilization processes. This journal is

Background: The use of chromium supplements is widespread for the prevention and treatment of diabetes mellitus but there are conflicting reports on efficacy, possibly reflecting discrepant effects across different populations. In the present studies, we t

The purpose of this investigation was to determine the utility of clinical swallowing examination (CSE) measures for detecting aspiration as defined by videofluoroscopic swallowing examination (VFSE). This study, involving 165 participants, is a follow-up to a previously published investigation of 60 participants. Findings are compared with that investigation as well as with other research on CSEs. The results suggest that clinicians can make an accurate judgment of the occurrence of aspiration in most poststroke patients. However, ruling out aspiration when it is absent appears more problematic. More work needs to be done if data collected from noninstrumented examinations are to be strongly predictive of the presence and absence of aspiration on VFSE. At present, there are no data to suggest that CSEs can be used to quantify aspiration or make adequate recommendations regarding patient care. (Contains 6 tables and 2 figures.)

In his comment, Gabet summarized his critiques regarding our identification of migrating knickpoints in the Sierra and our estimates of both timing and magnitude of surface uplift made using a wide variety of independent measures of fluvial geomorphology. Here, we review the evidence we used to interpret particular features as migrating knickpoints in a transient landscape and demonstrate that the evidence presented by Gabet in no way shows these are stationary features that can be attributed to heterogeneous lithology alone. The challenges we faced and assumptions we made to determine timing from these river profile forms were summarized in the original paper and again in Gabet's comment. We chose a range-wide approach using systematic topographic analysis and an ensemble of methods precisely because we recognize the modern heterogeneity and dynamic late Cenozoic geologic history. With this approach, we identified trends in timing and magnitude of surface uplift that were consistent along much of the length of the range and in both tributary and mainstem rivers. We were able to identify signatures of late Cenozoic tilting amidst the influence of heterogeneous lithology, latitudinal climate gradients, drainage area exchange, and variable depositional histories. We hope that readers recognize that rather than ignoring local complexity, the tectonic mechanism of late Cenozoic westward tilt and the ensuing transient response can explain the diversity in observed geomorphology. Particularly, geomorphic features such as the along- and between-river variability in incision as well as the distribution and form of both mainstem and tributary knickpoints and knickzones can be reconciled when such a transient response is filtered through the heterogeneous lithology and basin area exchange characteristic of the west side Sierra Nevada. Thus, while challenges preclude pinpointing timing of the most recent tectonic event within the late Cenozoic using river profile forms alone, we maintain that a significant tectonic event perturbed Sierra river profiles in the past 11 million years. In many landscapes, an estimate with such a degree of uncertainty would not move the needle on our understanding but for the Sierra, where some contend no major tectonic event has occurred since the late Cretaceous, this uncertain estimate is valuable. [ABSTRACT FROM AUTHOR]

The Lactobacillus species from gastrointestinal tracts of dogs of were isolated and tested for bile tolerance, growth in Oxgall and inhibition of Salmonella. The probiotic Lactobacillus reuteri was found to be most bile resistant and also exhibited the ability to inhibit the growth of pathogen Salmonella.

There has been considerable interest recently, in the formation of the source drain junctions of metal oxide semiconductor transistors using solid phase epitaxy (SPE) to activate the dopants rather than a traditional high temperature anneal. Previous studies have shown that this method results in high dopant activation as well as shallow junctions (due to the small thermal budget). In this we study the effect the temperature of SPE regrowth has on the boron activation. We find that boron activation has a monotonically increasing dependence on the temperature. Significantly, we show that by carrying out the SPE regrowth at temperatures above 1050 °C, it is possible to obtain active concentrations well above the electrical solubility limits. [ABSTRACT FROM AUTHOR]