1,775 research outputs found
Sea-level constraints on the amplitude and source distribution of Meltwater Pulse 1A.
During the last deglaciation, sea levels rose as ice sheets retreated. This climate transition was punctuated by periods of more intense melting; the largest and most rapid of these—Meltwater Pulse 1A—occurred about 14,500 years ago, with rates of sea-level rise reaching approximately 4 m per century1, 2, 3. Such rates of rise suggest ice-sheet instability, but the meltwater sources are poorly constrained, thus limiting our understanding of the causes and impacts of the event4, 5, 6, 7. In particular, geophysical modelling studies constrained by tropical sea-level records1, 8, 9 suggest an Antarctic contribution of more than seven metres, whereas most reconstructions10 from Antarctica indicate no substantial change in ice-sheet volume around the time of Meltwater Pulse 1A. Here we use a glacial isostatic adjustment model to reinterpret tropical sea-level reconstructions from Barbados2, the Sunda Shelf3 and Tahiti1. According to our results, global mean sea-level rise during Meltwater Pulse 1A was between 8.6 and 14.6 m (95% probability). As for the melt partitioning, we find an allowable contribution from Antarctica of either 4.1 to 10.0 m or 0 to 6.9 m (95% probability), using two recent estimates11, 12 of the contribution from the North American ice sheets. We conclude that with current geologic constraints, the method applied here is unable to support or refute the possibility of a significant Antarctic contribution to Meltwater Pulse 1A
Building sustainability assessment methods
Over last 15 years it has been increasingly important to understand the sustainability performance of buildings across a broad range of considerations. This has stimulated the development of a number of sustainability assessment tools intended to measure objectively a project's impact in sustainability terms and so encourage designers and planners to improve a building's performance. This paper examines the nature and contribution, as well as the limitations, of current sustainability rating assessment tools in evaluating building sustainability in different countries. Two yardsticks are used to review the current tools: first, how well they relate to the goal of sustainable development, and second, how adequately they adhere to the principles of objective assessment. Scope for further development of sustainability assessment tools is identified – in particular, the need for tools to assess more adequately how buildings provide well-being, and to expand how assessment systems capture qualitative information. The paper proposes that methodology and procedures of assessment methods should feature the broad participation of user groups drawn from the public. This paper was first published in the Proceedings of the Institution of Civil Engineers - Engineering Sustainability and is reproduced with their permission http://www.icevirtuallibrary.com/content/journals Permission is granted by ICE Publishing to print one copy for personal use. Any other use of these PDF files is subject to reprint fees.</p
The cannabinoid WIN 55,212-2 prevents neuroendocrine differentiation of LNCaP prostate cancer cells
BACKGROUND: Neuroendocrine (NE) differentiation represents a common feature of prostate cancer and is associated with accelerated disease progression and poor clinical outcome. Nowadays, there is no treatment for this aggressive form of prostate cancer. The aim of this study was to determine the influence of the cannabinoid WIN 55,212-2 (WIN, a non-selective cannabinoid CB1 and CB2 receptor agonist) on the NE differentiation of prostate cancer cells.METHODS: NE differentiation of prostate cancer LNCaP cells was induced by serum deprivation or by incubation with interleukin-6, for 6 days. Levels of NE markers and signaling proteins were determined by western blotting. Levels of cannabinoid receptors were determined by quantitative PCR. The involvement of signaling cascades was investigated by pharmacological inhibition and small interfering RNA.RESULTS: The differentiated LNCaP cells exhibited neurite outgrowth, and increased the expression of the typical NE markers neuron-specific enolase and βIII tubulin (βIII Tub). Treatment with 3 μM WIN inhibited NK differentiation of LNCaP cells. The cannabinoid WIN downregulated the PI3K/Akt/mTOR signaling pathway, resulting in NE differentiation inhibition. In addition, an activation of AMP-activated protein kinase (AMPK) was observed in WIN-treated cells, which correlated with a decrease in the NE markers expression. Our results also show that during NE differentiation the expression of cannabinoid receptors CB1 and CB2 dramatically decreases.CONCLUSIONS: Taken together, we demonstrate that PI3K/Akt/AMPK might be an important axis modulating NE differentiation of prostate cancer that is blocked by the cannabinoid WIN, pointing to a therapeutic potential of cannabinoids against NE prostate cancer.Prostate Cancer and Prostatic Diseases advance online publication, 21 June 2016; doi:10.1038/pcan.2016.19.</p
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The Sloan Digital Sky Survey quasar catalog: Tenth data release â&dagger
We present the Data Release 10 Quasar (DR10Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky
Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the first 2.5 years of the survey and that are
confirmed as quasars via visual inspection of the spectra, have luminosities Mi[z = 2] < −20.5 (in a ΛCDMcosmology with H0 = 70 km s−1 Mpc−1,
ΩM = 0.3, and ΩΛ = 0.7), and either display at least one emission line with a full width at half maximum (FWHM) larger than 500 km s−1 or,
if not, have interesting/complex absorption features. The catalog also includes known quasars (mostly from SDSS-I and II) that were reobserved
by BOSS. The catalog contains 166 583 quasars (74 454 are new discoveries since SDSS-DR9) detected over 6373 deg2 with robust identification
and redshift measured by a combination of principal component eigenspectra. The number of quasars with z > 2.15 (117 668) is ∼5 times greater
than the number of z > 2.15 quasars known prior to BOSS. Redshifts and FWHMs are provided for the strongest emission lines (C iv, C iii,
Mg ii). The catalog identifies 16 461 broad absorption line quasars and gives their characteristics. For each object, the catalog presents five-band
(u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag and information on the optical morphology and selection method. The
catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys.
The calibrated digital spectra cover the wavelength region 3600−10 500 Å at a spectral resolution in the range 1300 < R < 2500; the spectra can
be retrieved from the SDSS Catalog Archive Server. We also provide a supplemental list of an additional 2376 quasars that have been identified
among the galaxy targets of the SDSS-III/BOSS.I.P. received partial support from Center of Excellence in
Astrophysics and Associated Technologies (PFB 06). The French Participation
Group to SDSS-III was supported by the Agence Nationale de la Recherche
under contracts ANR-08-BLAN-0222 and ANR-12-BS05-0015. A.D.M. is
a research fellow of the Alexander von Humboldt Foundation of Germany
and was partially supported through NSF Grant 1211112 and NASA ADAP
award NNX12AE38G. Funding for SDSS-III has been provided by the
Alfred P. Sloan Foundation, the Participating Institutions, the National Science
Foundation, and the US Department of Energy Office of Science.This is the published version. It originally appeared in Astronomy and Astrophysics and is available online at http://www.aanda.org/articles/aa/abs/2014/03/aa22691-13/aa22691-13.html
A Search for Dark Higgs Bosons
Recent astrophysical and terrestrial experiments have motivated the proposal
of a dark sector with GeV-scale gauge boson force carriers and new Higgs
bosons. We present a search for a dark Higgs boson using 516 fb-1 of data
collected with the BABAR detector. We do not observe a significant signal and
we set 90% confidence level upper limits on the product of the Standard
Model-dark sector mixing angle and the dark sector coupling constant.Comment: 7 pages, 5 postscript figures, published version with improved plots
for b/w printin
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The Sloan Digital Sky Survey quasar catalog: Tenth data release â&dagger
We present the Data Release 10 Quasar (DR10Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky
Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the first 2.5 years of the survey and that are
confirmed as quasars via visual inspection of the spectra, have luminosities Mi[z = 2] < −20.5 (in a ΛCDMcosmology with H0 = 70 km s−1 Mpc−1,
ΩM = 0.3, and ΩΛ = 0.7), and either display at least one emission line with a full width at half maximum (FWHM) larger than 500 km s−1 or,
if not, have interesting/complex absorption features. The catalog also includes known quasars (mostly from SDSS-I and II) that were reobserved
by BOSS. The catalog contains 166 583 quasars (74 454 are new discoveries since SDSS-DR9) detected over 6373 deg2 with robust identification
and redshift measured by a combination of principal component eigenspectra. The number of quasars with z > 2.15 (117 668) is ∼5 times greater
than the number of z > 2.15 quasars known prior to BOSS. Redshifts and FWHMs are provided for the strongest emission lines (C iv, C iii,
Mg ii). The catalog identifies 16 461 broad absorption line quasars and gives their characteristics. For each object, the catalog presents five-band
(u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag and information on the optical morphology and selection method. The
catalog also contains X-ray, ultraviolet, near-infrared, and radio emission properties of the quasars, when available, from other large-area surveys.
The calibrated digital spectra cover the wavelength region 3600−10 500 Å at a spectral resolution in the range 1300 < R < 2500; the spectra can
be retrieved from the SDSS Catalog Archive Server. We also provide a supplemental list of an additional 2376 quasars that have been identified
among the galaxy targets of the SDSS-III/BOSS.I.P. received partial support from Center of Excellence in
Astrophysics and Associated Technologies (PFB 06). The French Participation
Group to SDSS-III was supported by the Agence Nationale de la Recherche
under contracts ANR-08-BLAN-0222 and ANR-12-BS05-0015. A.D.M. is
a research fellow of the Alexander von Humboldt Foundation of Germany
and was partially supported through NSF Grant 1211112 and NASA ADAP
award NNX12AE38G. Funding for SDSS-III has been provided by the
Alfred P. Sloan Foundation, the Participating Institutions, the National Science
Foundation, and the US Department of Energy Office of Science.This is the published version. It originally appeared in Astronomy and Astrophysics and is available online at http://www.aanda.org/articles/aa/abs/2014/03/aa22691-13/aa22691-13.html
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Attribution: how is it relevant for loss and damage policy and practice?
Attribution has become a recurring issue in discussions about Loss and Damage (L&D). In this highly-politicised context, attribution is often associated with responsibility and blame; and linked to debates about liability and compensation. The aim of attribution science, however, is not to establish responsibility, but to further scientific understanding of causal links between elements of the Earth System and society. This research into causality could inform the management of climate-related risks through improved understanding of drivers of relevant hazards, or, more widely, vulnerability and exposure; with potential benefits regardless of political positions on L&D. Experience shows that it is nevertheless difficult to have open discussions about the science in the policy sphere. This is not only a missed opportunity, but also problematic in that it could inhibit understanding of scientific results and uncertainties, potentially leading to policy planning which does not have sufficient scientific evidence to support it. In this chapter, we first explore this dilemma for science-policy dialogue, summarising several years of research into stakeholder perspectives of attribution in the context of L&D. We then aim to provide clarity about the scientific research available, through an overview of research which might contribute evidence about the causal connections between anthropogenic climate change and losses and damages, including climate science, but also other fields which examine other drivers of hazard, exposure, and vulnerability. Finally, we explore potential applications of attribution research, suggesting that an integrated and nuanced approach has potential to inform planning to avert, minimise and address losses and damages. The key messages are
In the political context of climate negotiations, questions about whether losses and damages can be attributed to anthropogenic climate change are often linked to issues of responsibility, blame, and liability.
Attribution science does not aim to establish responsibility or blame, but rather to investigate drivers of change.
Attribution science is advancing rapidly, and has potential to increase understanding of how climate variability and change is influencing slow onset and extreme weather events, and how this interacts with other drivers of risk, including socio-economic drivers, to influence losses and damages.
Over time, some uncertainties in the science will be reduced, as the anthropogenic climate change signal becomes stronger, and understanding of climate variability and change develops.
However, some uncertainties will not be eliminated. Uncertainty is common in science, and does not prevent useful applications in policy, but might determine which applications are appropriate. It is important to highlight that in attribution studies, the strength of evidence varies substantially between different kinds of slow onset and extreme weather events, and between regions. Policy-makers should not expect the later emergence of conclusive evidence about the influence of climate variability and change on specific incidences of losses and damages; and, in particular, should not expect the strength of evidence to be equal between events, and between countries.
Rather than waiting for further confidence in attribution studies, there is potential to start working now to integrate science into policy and practice, to help understand and tackle drivers of losses and damages, informing prevention, recovery, rehabilitation, and transformation
Search for rare quark-annihilation decays, B --> Ds(*) Phi
We report on searches for B- --> Ds- Phi and B- --> Ds*- Phi. In the context
of the Standard Model, these decays are expected to be highly suppressed since
they proceed through annihilation of the b and u-bar quarks in the B- meson.
Our results are based on 234 million Upsilon(4S) --> B Bbar decays collected
with the BABAR detector at SLAC. We find no evidence for these decays, and we
set Bayesian 90% confidence level upper limits on the branching fractions BF(B-
--> Ds- Phi) Ds*- Phi)<1.2x10^(-5). These results
are consistent with Standard Model expectations.Comment: 8 pages, 3 postscript figues, submitted to Phys. Rev. D (Rapid
Communications
Serological profile of foot-and-mouth disease in wildlife populations of West and Central Africa with special reference to Syncerus caffer subspecies
The role which West and Central African wildlife populations might play in the transmission dynamics of FMD is not known nor have studies been performed in order to assess the distribution and prevalence of FMD in wild animal species inhabiting those specific regions of Africa. This study reports the FMD serological profile extracted from samples (n = 696) collected from wildlife of West and Central Africa between 1999 and 2003. An overall prevalence of FMDV NSP reactive sera of 31.0% (216/696) was estimated, where a significant difference in seropositivity (p = 0.000) was reported for buffalo (64.8%) as opposed to other wild animal species tested (17.8%). Different levels of exposure to the FMDV resulted for each of the buffalo subspecies sampled (p = 0.031): 68.4%, 50.0% and 0% for Nile Buffalo, West African Buffalo and African Forest Buffalo, respectively. The characterisation of the FMDV serotypes tested for buffalo found presence of antibodies against all the six FMDV serotypes tested, although high estimates for type O and SAT 3 were reported for Central Africa. Different patterns of reaction to the six FMDV serotypes tested were recorded, from sera only positive for a single serotype to multiple reactivities. The results confirmed that FMDV circulates in wild ruminants populating both West and Central Africa rangelands and in particular in buffalo, also suggesting that multiple FMDV serotypes might be involved with type O, SAT 2 and SAT 1 being dominant. Differences in serotype and spill-over risk between wildlife and livestock likely reflect regional geography, historical circulation and differing trade and livestock systems
IceCube-Gen2: A Vision for the Future of Neutrino Astronomy in Antarctica
20 pages, 12 figures. Address correspondence to: E. Blaufuss, F. Halzen, C. Kopper (Changed to add one missing author, no other changes from initial version.)20 pages, 12 figures. Address correspondence to: E. Blaufuss, F. Halzen, C. Kopper (Changed to add one missing author, no other changes from initial version.)20 pages, 12 figures. Address correspondence to: E. Blaufuss, F. Halzen, C. Kopper (Changed to add one missing author, no other changes from initial version.)The recent observation by the IceCube neutrino observatory of an astrophysical flux of neutrinos represents the "first light" in the nascent field of neutrino astronomy. The observed diffuse neutrino flux seems to suggest a much larger level of hadronic activity in the non-thermal universe than previously thought and suggests a rich discovery potential for a larger neutrino observatory. This document presents a vision for an substantial expansion of the current IceCube detector, IceCube-Gen2, including the aim of instrumenting a volume of clear glacial ice at the South Pole to deliver substantial increases in the astrophysical neutrino sample for all flavors. A detector of this size would have a rich physics program with the goal to resolve the sources of these astrophysical neutrinos, discover GZK neutrinos, and be a leading observatory in future multi-messenger astronomy programs
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