276 research outputs found
Stripes ordering in self-stratification experiments of binary and ternary granular mixtures
The self-stratification of binary and ternary granular mixtures has been
experimentally investigated. Ternary mixtures lead to a particular ordering of
the strates which was not accounted for in former explanations. Bouncing grains
are found to have an important effect on strate formation. A complementary
mechanism for self-stratification of binary and ternary granular mixtures is
proposed.Comment: 4 pages, 5 figures. submitted for pubication, guess wher
Fabrication of stable and reproducible sub-micron tunnel junctions
We have performed a detailed study of the time stability and reproducibility
of sub-micron tunnel junctions, fabricated using standard
double angle shadow evaporations. We have found that by aggressively cleaning
the substrate before the evaporations, thus preventing any contamination of the
junction, we obtained perfectly stable oxide barriers. We also present
measurements on large ensembles of junctions which prove the reproducibility of
the fabrication process. The measured tunnel resistance variance in large
ensembles of identically fabricated junctions is in the range of only a few
percents. Finally, we have studied the effect of different thermal treatments
on the junction barrier. This is especially important for multiple step
fabrication processes which imply annealing the junction.Comment: 4 pages, 3 figure
Non-invasive assessment of murine PD-L1 levels in syngeneic tumor models by nuclear imaging with nanobody tracers
Blockade of the inhibitory PD-1/PD-L1 immune checkpoint axis is a promising cancer treatment. Nonetheless, a significant number of patients and malignancies do not respond to this therapy. To develop a screen for response to PD-1/PD-L1 inhibition, it is critical to develop a non-invasive tool to accurately assess dynamic immune checkpoint expression. Here we evaluated non-invasive SPECT/CT imaging of PD-L1 expression, in murine tumor models with varying PD-L1 expression, using high affinity PD-L1-specific nanobodies (Nbs). We generated and characterized 37 Nbs recognizing mouse PD-L1. Among those, four Nbs C3, C7, E2 and E4 were selected and evaluated for preclinical imaging of PD-L1 in syngeneic mice. We performed SPECT/CT imaging in wild type versus PD-L1 knock-out mice, using Technetium-99m (99mTc) labeled Nbs. Nb C3 and E2 showed specific antigen binding and beneficial biodistribution. Through the use of CRISPR/Cas9 PD-L1 knock-out TC-1 lung epithelial cell lines, we demonstrate that SPECT/CT imaging using Nb C3 and E2 identifies PD-L1 expressing tumors, but not PD-L1 non-expressing tumors, thereby confirming the diagnostic potential of the selected Nbs. In conclusion, these data show that Nbs C3 and E2 can be used to non-invasively image PD-L1 levels in the tumor, with the strength of the signal correlating with PD-L1 levels. These findings warrant further research into the use of Nbs as a tool to image inhibitory signals in the tumor environment
Genes Suggest Ancestral Colour Polymorphisms Are Shared across Morphologically Cryptic Species in Arctic Bumblebees
email Suzanne orcd idCopyright: © 2015 Williams et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Least-cost and 2 °C-compliant mitigation pathways robust to physical uncertainty, economic paradigms, and intergenerational cost distribution
Each run of an integrated assessment models produces a single mitigation pathway consistent with stated objectives (e.g. maximum temperature) and optimizing some objective function (e.g. minimizing total discounted costs of mitigation). Even though models can be run thousands of times, it is unclear how built-in assumptions constrain the final set of pathways. Here we aim at broadly exploring the space of possible mitigation scenarios for a given mitigation target, and at characterizing the sets of pathways that are (near-)optimal, taking uncertainties into account. We produce an extensive set of CO2 emission pathways that stay below 2 °C of warming using a reduced-form climate-carbon model with a 1000 different physical states. We then identify 18 sets of quasi 'least-cost' mitigation pathways, under six assumptions about cost functions and three different cost minimization functions embarking different visions of intergenerational cost distribution. A first key outcome is that the absence or presence of inertia in the cost function plays a pivotal role in the resulting set of least-cost pathways. Second, despite inherent structural differences, we find common pathways across the 18 combinations in 96% of the physical states studied. Interpreting these common pathways as robust economically and in terms of intergenerational distribution, we shed light on some of their characteristics, even though these robust pathways differ for each physical state
The 6 May 1976 Friuli earthquake: re-evaluating and consolidating
The aim of this paper is to propose the creation, in terms of European Macroseismic
Scale (EMS-98), of the entire macroseismic fi eld of the 6 May 1976 Friuli earthquake.
Only forty odd years have passed, and nothwithsatnding that there is a huge quantity
of existing data, it was still disturbing to fi nd that much of the original data are missing
and probably lost forever Efforts have therefore been made to fi nd additional and
still unknown primary data. For the majority of the collected national data sets, a reevaluation
was then possible. This study presents the comprehensive macroseismic
data set for 14 European countries. It is, to our knowledge, one of the largest European
data sets, consisting of 3423 intensity data points (IDPs). The earthquake was felt from
Rome to the Baltic Sea, and from Belgium to Warsaw. The maximum intensity 10
EMS-98 was reached in eight localities in Friuli (Italy). Compared to previous studies,
the Imax values have changed from country to country, in some cases being lowered due
to methodological differences, but in the case of three among the most hit countries,
Imax is now higher than in the previous studies, mainly due to the new data.Published417-4444T. Sismicità dell'ItaliaJCR Journa
Anatomy of phreatic eruptions
This study investigates phreatic eruptions at two similar volcanoes, Kawah Ijen (Indonesia) and White Island (New Zealand). By carefully processing broadband seismic signals, we reveal seismic signatures and characteristics of these eruptions. At both volcanoes, the phreatic eruptions are initiated by a very-long-period (VLP) seismic event located at shallow depths between 700 and 900 m below the crater region, and may be triggered by excitation of gas trapped behind a ductile magma carapace. The shallow hydrothermal systems respond in different ways. At Kawah Ijen, the stress change induced by VLPs directly triggers an eigenoscillation of the hyperacidic lake. This so-called seiche is characterized by long-lasting, long-period oscillations with frequencies governed by the dimensions of the crater lake. A progressive lateral rupture of a seal below the crater lake and/or fluids migrating toward the surface is seismically recorded ∼ 15 min later as high-frequency bursts superimposed to tilt signals. At White Island, the hydrothermal system later (∼ 25 min) responds by radiating harmonic tremor at a fixed location that could be generated through eddy-shedding. These seismic signals shed light on several aspects of phreatic eruptions, their generation and timeline. They are mostly recorded at periods longer than tens of seconds further emphasizing the need to deploy broadband seismic equipment close to active volcanic activity
Mitigation and development pathways in the near- to mid-term (Chapter 4)
This chapter focuses on accelerating mitigation and on shifting development pathways to increased sustainability, based on literature particularly at national scale. While previous WGIII assessments have discussed mitigation pathways, focus on development pathways is more recent. The timeframe is the near term (now up to 2030) to mid-term (2030 to 2050), complementing Chapter 3 on the long term (from 2050 onward)
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