Stable soils provide valuable ecosystem services and mechanical soil stability is enhanced by the presence of arbuscular mycorrhizal fungi (AMF). Soil aggregation, which is the major driver of ...mechanical soil stability, is often treated as a static phenomenon, even though aggregate turnover is continually ongoing. In fact, some breakdown of macroaggregates is necessary to allow new aggregate formation and inclusion of new organic matter into microaggregates. We determined how aggregate turnover times were affected by AMF by tracking movement of rare earth elements (REE), applied as their immobile oxides, between aggregate size classes, and using X-ray fluorescence microscopy to spatially localize REEs in a sample of aggregates. Here we show that AMF increased large macroaggregate formation and slowed down disintegration of large and small macroaggregates. Microaggregate turnover was increased in the presence of AMF. Internal aggregate organization suggested that although formation of microaggregates by accretion of soil to particulate organic matter is common, it is not the only mechanism in operation.
Deactivation of heterogeneous catalysts is a ubiquitous problem that causes loss of catalytic rate with time. This review on deactivation and regeneration of heterogeneous catalysts classifies ...deactivation by type (chemical, thermal, and mechanical) and by mechanism (poisoning, fouling, thermal degradation, vapor formation, vapor-solid and solid-solid reactions, and attrition/crushing). The key features and considerations for each of these deactivation types is reviewed in detail with reference to the latest literature reports in these areas. Two case studies on the deactivation mechanisms of catalysts used for cobalt Fischer-Tropsch and selective catalytic reduction are considered to provide additional depth in the topics of sintering, coking, poisoning, and fouling. Regeneration considerations and options are also briefly discussed for each deactivation mechanism.
Patients with diabetes mellitus are at increased risk of cancer development. Metformin is a well-established, effective agent for the management of type 2 diabetes mellitus. Epidemiological studies ...have identified an association between metformin use and a beneficial effect on cancer prevention and treatment, which has led to increasing interest in the potential use of metformin as an anticancer agent. Basic science has provided a better understanding of the mechanism of action of metformin and the potential for metformin to modulate molecular pathways involved in cancer cell signaling and metabolism. This article outlines the link between metformin and cancer, the potential for metformin in oncology, and limitations of currently available evidence.
The scholar denied Morris, Aldon
2015., 20150827, 2015, 2015-08-27
eBook
In this groundbreaking book, Aldon D. Morris's ambition is truly monumental: to help rewrite the history of sociology and to acknowledge the primacy of W. E. B. Du Bois's work in the founding of the ...discipline. Calling into question the prevailing narrative of how sociology developed, Morris, a major scholar of social movements, probes the way in which the history of the discipline has traditionally given credit to Robert E. Park at the University of Chicago, who worked with the conservative black leader Booker T. Washington to render Du Bois invisible. Morris uncovers the seminal theoretical work of Du Bois in developing a "scientific" sociology through a variety of methodologies and examines how the leading scholars of the day disparaged and ignored Du Bois's work.The Scholar Deniedis based on extensive, rigorous primary source research; the book is the result of a decade of research, writing, and revision. In exposing the economic and political factors that marginalized the contributions of Du Bois and enabled Park and his colleagues to be recognized as the "fathers" of the discipline, Morris delivers a wholly new narrative of American intellectual and social history that places one of America's key intellectuals, W. E. B. Du Bois, at its center.The Scholar Deniedis a must-read for anyone interested in American history, racial inequality, and the academy. In challenging our understanding of the past, the book promises to engender debate and discussion.
Abstract
Recently, carbon dioxide capture and conversion, along with hydrogen from renewable resources, provide an alternative approach to synthesis of useful fuels and chemicals. People are ...increasingly interested in developing innovative carbon dioxide hydrogenation catalysts, and the pace of progress in this area is accelerating. Accordingly, this perspective presents current state of the art and outlook in synthesis of light olefins, dimethyl ether, liquid fuels, and alcohols through two leading hydrogenation mechanisms: methanol reaction and Fischer-Tropsch based carbon dioxide hydrogenation. The future research directions for developing new heterogeneous catalysts with transformational technologies, including 3D printing and artificial intelligence, are provided.
Structure of the Lightest Tin Isotopes Morris, T D; Simonis, J; Stroberg, S R ...
Physical review letters,
2018-Apr-13, Letnik:
120, Številka:
15
Journal Article
Recenzirano
Odprti dostop
We link the structure of nuclei around ^{100}Sn, the heaviest doubly magic nucleus with equal neutron and proton numbers (N=Z=50), to nucleon-nucleon (NN) and three-nucleon (NNN) forces constrained ...by data of few-nucleon systems. Our results indicate that ^{100}Sn is doubly magic, and we predict its quadrupole collectivity. We present precise computations of ^{101}Sn based on three-particle-two-hole excitations of ^{100}Sn, and we find that one interaction accurately reproduces the small splitting between the lowest J^{π}=7/2^{+} and 5/2^{+} states.
Oxy-fuel combustion has received significant attention because it is widely considered to be a promising method for cost-effective CO2 capture. The key to the success of oxy-fuel combustion processes ...is the availability of inexpensive O2. Therefore, development of low-cost and robust technologies for air separation or separating O2 from air is critical. Great progress has been made in this research and development area. However, a recent review of the progress made in the area is lacking. This review is designed to fill the gap. The review focuses on three major technologies for separating oxygen from air, including membranes, adsorption, and chemical-looping with oxygen uncoupling. The separation principles, characteristics, challenges and the associated solutions of these major technologies are systematically discussed. Future opportunities are outlined for each.
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Brain metastatic breast cancer (BMBC) is uniformly fatal and increasing in frequency. Despite its devastating outcome, mechanisms causing BMBC remain largely unknown. The mechanisms that implicate ...circulating tumor cells (CTCs) in metastatic disease, notably in BMBC, remain elusive. We characterize CTCs isolated from peripheral blood mononuclear cells of patients with breast cancer and also develop CTC lines from three of these patients. In epithelial cell adhesion molecule (EpCAM)-negative CTCs, we identified a potential signature of brain metastasis comprising "brain metastasis selected markers (BMSMs)" HER2+ / EGFR+ / HPSE+ / Notch1+. These CTCs, which are not captured by the CellSearch platform because of their EpCAM negativity, were analyzed for cell invasiveness and metastatic competency in vivo. CTC lines expressing the BMSM signature were highly invasive and capable of generating brain and lung metastases when xenografted in nude mice. Notably, increased brain metastatic capabilities, frequency, and quantitation were detected in EpCAM- CTCs overexpressing the BMSM signature. The presence of proteins of the BMSM CTC signature was also detected in the metastatic lesions of animals. Collectively, we provide evidence of isolation, characterization, and long-term culture of human breast cancer CTCs, leading to the description of a BMSM protein signature that is suggestive of CTC metastatic competency to the brain.
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