5 research outputs found
Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
We report a measurement of the bottom-strange meson mixing phase \beta_s
using the time evolution of B0_s -> J/\psi (->\mu+\mu-) \phi (-> K+ K-) decays
in which the quark-flavor content of the bottom-strange meson is identified at
production. This measurement uses the full data set of proton-antiproton
collisions at sqrt(s)= 1.96 TeV collected by the Collider Detector experiment
at the Fermilab Tevatron, corresponding to 9.6 fb-1 of integrated luminosity.
We report confidence regions in the two-dimensional space of \beta_s and the
B0_s decay-width difference \Delta\Gamma_s, and measure \beta_s in [-\pi/2,
-1.51] U [-0.06, 0.30] U [1.26, \pi/2] at the 68% confidence level, in
agreement with the standard model expectation. Assuming the standard model
value of \beta_s, we also determine \Delta\Gamma_s = 0.068 +- 0.026 (stat) +-
0.009 (syst) ps-1 and the mean B0_s lifetime, \tau_s = 1.528 +- 0.019 (stat) +-
0.009 (syst) ps, which are consistent and competitive with determinations by
other experiments.Comment: 8 pages, 2 figures, Phys. Rev. Lett 109, 171802 (2012
Big disparities in CH4 emission patterns from landfills between the United States and China and their behind driving forces
Waste is the bridge linking resource consumption and greenhouse gas generation, and waste landfills are the main anthropogenic source of methane (CH4). The United States (US)–China Joint Glasgow Declaration and the Global Methane Pledge are committed to reducing tractable CH4 emissions; however, differences between the involved countries as well as their generation forecast processes have hampered cooperation. In this study, we provide a deep insight into CH4 emissions from municipal solid waste (MSW) landfills and identify the disparities in CH4 emissions with local socio-economic conditions. The US and China, the world's two largest economies, generated approximately 3.73 and 1.48 million tonnes of CH4 from 1248 to 1955 landfills in 2012 using the FOD/bottom-up method, with corresponding 26.93 and 11.94 kg per tonne waste and emission value from each landfill ranging between 100 and 105 and 10−5–105 tonnes. The spatial distribution was also quantified and compared with national, state/province, and urban agglomeration perspectives based on historical MSW variations (1990–2015) to clarify the triangular relationship between the economic situation, waste properties, and landfill CH4 emissions. High-density CH4 emission regions spatially overlapped with highly developed urban agglomerations, positively correlated with the local gross domestic product (GDP) and population (p 4 emissions from the waste sector. The increase in tertiary industry might reduce the waste sector's CH4 emissions. This study will help to understand this new triangular relationship and predict future patterns of CH4 emissions.</p
Guidelines for the use and interpretation of assays for monitoring autophagy
In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field