1,486 research outputs found
Three-year observations of halocarbons at the Nepal Climate Observatory at Pyramid (NCO-P, 5079 m a.s.l.) on the Himalayan range
A monitoring programme for halogenated climate-altering gases has been established in the frame of the SHARE EV-K<sup>2</sup>-CNR project at the Nepal Climate Laboratory – Pyramid in the Himalayan range at the altitude of 5079 m a.s.l. The site is very well located to provide important insights on changes in atmospheric composition in a region that is of great significance for emissions of both anthropogenic and biogenic halogenated compounds. Measurements are performed since March 2006, with grab samples collected on a weekly basis. The first three years of data have been analysed. After the identification of the atmospheric background values for fourteen halocarbons, the frequency of occurrence of pollution events have been compared with the same kind of analysis for data collected at other global background stations. The analysis showed the fully halogenated species, whose production and consumption are regulated under the Montreal Protocol, show a significant occurrence of "above the baseline" values, as a consequence of their current use in the developing countries surrounding the region, meanwhile the hydrogenated gases, more recently introduced into the market, show less frequent spikes. <br><br> Atmospheric concentration trends have been calculated as well, and they showed a fast increase, ranging from 5.7 to 12.6%, of all the hydrogenated species, and a clear decrease of methyl chloroform (−17.7%). The comparison with time series from other stations has also allowed to derive Meridional gradients, which are absent for long living well mixed species, while for the more reactive species, the gradient increases inversely with respect to their atmospheric lifetime. The effect of long range transport and of local events on the atmospheric composition at the station has been analysed as well, allowing the identification of relevant source regions the Northern half of the Indian sub-continent. Also, at finer spatial scales, a smaller, local contribution of forest fires from the Khumbu valley has been detected
An analytical inversion method for determining regional and global emissions of greenhouse gases: Sensitivity studies and application to halocarbons
A new analytical inversion method has been developed to determine the regional and global emissions of long-lived atmospheric trace gases. It exploits in situ measurement data from three global networks and builds on backward simulations with a Lagrangian particle dispersion model. The emission information is extracted from the observed concentration increases over a baseline that is itself objectively determined by the inversion algorithm. The method was applied to two hydrofluorocarbons (HFC-134a, HFC-152a) and a hydrochlorofluorocarbon (HCFC-22) for the period January 2005 until March 2007. Detailed sensitivity studies with synthetic as well as with real measurement data were done to quantify the influence on the results of the a priori emissions and their uncertainties as well as of the observation and model errors. It was found that the global a posteriori emissions of HFC-134a, HFC-152a and HCFC-22 all increased from 2005 to 2006. Large increases (21%, 16%, 18%, respectively) from 2005 to 2006 were found for China, whereas the emission changes in North America (−9%, 23%, 17%, respectively) and Europe (11%, 11%, −4%, respectively) were mostly smaller and less systematic. For Europe, the a posteriori emissions of HFC-134a and HFC-152a were slightly higher than the a priori emissions reported to the United Nations Framework Convention on Climate Change (UNFCCC). For HCFC-22, the a posteriori emissions for Europe were substantially (by almost a factor 2) higher than the a priori emissions used, which were based on HCFC consumption data reported to the United Nations Environment Programme (UNEP). Combined with the reported strongly decreasing HCFC consumption in Europe, this suggests a substantial time lag between the reported time of the HCFC-22 consumption and the actual time of the HCFC-22 emission. Conversely, in China where HCFC consumption is increasing rapidly according to the UNEP data, the a posteriori emissions are only about 40% of the a priori emissions. This reveals a substantial storage of HCFC-22 and potential for future emissions in China. Deficiencies in the geographical distribution of stations measuring halocarbons in relation to estimating regional emissions are also discussed in the paper. Applications of the inversion algorithm to other greenhouse gases such as methane, nitrous oxide or carbon dioxide are foreseen for the future
Towards a circular economy for the plastic packaging sector: Insights from the Italian case
Achieving a circular economy (CE) has become a strategic priority for the plastic packaging industry to imple-ment long-term business sustainability while meeting legislative requirements. In this view, the evolution of cir-cularity practices in relation to technological, regulatory, and socio-economic factors and the implications for different value chain actors are open streams of research. This study aims to assess trends and meaningful changes in the adoption of circularity practices from the perspective of different value chain actors, under the ef-fects of leading CE barriers and enablers. A longitudinal analysis of the influence of these factors in relation to CE practices adopted by the Italian plastic packaging sector was conducted for the years 2011, 2015, and 2019. The involvement in plastic recovery became a predominant CE strategy over time, thanks to technological availability and a more mature regulatory framework. Our results suggest a gradual shift from scattered CE implementations to a more systemic approach to CE integrating upstream and downstream solutions. However, this transition oc-curred at different speeds and levels across the supply chain, as companies perceived factors differently and, con-sequently, implemented different types of CE practices. Therefore, increased collaboration and alignment across the supply chain are still required to overcome existing challenges. Based on our analysis, a focus group with stakeholders and experts of the plastic industry drew possible future avenues for the plastic packaging sector. Suggested priority actions include advancement of new and emerging recycling technologies, prioritization of economically viable and closed-loop alternatives to recover plastic waste, and alignment between national and international CE directives. These results extend our understanding of the CE transition and shed new light on the ways in which the industry can address existing barriers in different tiers for a system-wide impact. (c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved
History of chemically and radiatively important atmospheric gases from the Advanced Global Atmospheric Gases Experiment (AGAGE)
We present the organization, instrumentation, datasets, data interpretation,
modeling, and accomplishments of the multinational global atmospheric
measurement program AGAGE (Advanced Global Atmospheric Gases Experiment).
AGAGE is distinguished by its capability to measure globally, at high
frequency, and at multiple sites all the important species in the Montreal
Protocol and all the important non-carbon-dioxide (non-CO<sub>2</sub>) gases
assessed by the Intergovernmental Panel on Climate Change (CO<sub>2</sub> is
also measured at several sites). The scientific objectives of AGAGE are
important in furthering our understanding of global chemical and climatic
phenomena. They are the following: (1) to accurately measure the temporal and
spatial distributions of anthropogenic gases that contribute the majority of
reactive halogen to the stratosphere and/or are strong infrared absorbers
(chlorocarbons, chlorofluorocarbons – CFCs, bromocarbons,
hydrochlorofluorocarbons – HCFCs, hydrofluorocarbons – HFCs and
polyfluorinated compounds (perfluorocarbons – PFCs), nitrogen trifluoride –
NF<sub>3</sub>, sulfuryl fluoride – SO<sub>2</sub>F<sub>2</sub>, and sulfur hexafluoride –
SF<sub>6</sub>) and use these measurements to determine the global rates of
their emission and/or destruction (i.e., lifetimes); (2) to accurately
measure the global distributions and temporal behaviors and determine the
sources and sinks of non-CO<sub>2</sub> biogenic–anthropogenic gases important
to climate change and/or ozone depletion (methane – CH<sub>4</sub>, nitrous
oxide – N<sub>2</sub>O,
carbon monoxide – CO, molecular hydrogen – H<sub>2</sub>, methyl chloride
– CH<sub>3</sub>Cl, and methyl bromide – CH<sub>3</sub>Br); (3) to identify new
long-lived greenhouse and ozone-depleting gases (e.g., SO<sub>2</sub>F<sub>2</sub>,
NF<sub>3</sub>, heavy PFCs (C<sub>4</sub>F<sub>10</sub>, C<sub>5</sub>F<sub>12</sub>,
C<sub>6</sub>F<sub>14</sub>, C<sub>7</sub>F<sub>16</sub>, and C<sub>8</sub>F<sub>18</sub>) and
hydrofluoroolefins (HFOs; e.g., CH<sub>2</sub> = CFCF<sub>3</sub>) have been
identified in AGAGE), initiate the real-time monitoring of these new gases,
and reconstruct their past histories from AGAGE, air archive, and firn air
measurements; (4) to determine the average concentrations and trends of
tropospheric hydroxyl radicals (OH) from the rates of destruction of
atmospheric trichloroethane (CH<sub>3</sub>CCl<sub>3</sub>), HFCs, and HCFCs and estimates
of their emissions; (5) to determine from atmospheric observations and
estimates of their destruction rates the magnitudes and distributions by
region of surface sources and sinks of all measured gases; (6) to provide
accurate data on the global accumulation of many of these trace gases that
are used to test the synoptic-, regional-, and global-scale circulations
predicted by three-dimensional models; and (7) to provide global and regional
measurements of methane, carbon monoxide, and molecular hydrogen and
estimates of hydroxyl levels to test primary atmospheric oxidation pathways
at midlatitudes and the tropics. Network Information and Data Repository:
<a href="http://agage.mit.edu/data" target="_blank">http://agage.mit.edu/data</a> or
<a href="http://cdiac.ess-dive.lbl.gov/ndps/alegage.html" target="_blank">http://cdiac.ess-dive.lbl.gov/ndps/alegage.html</a>
(<a href="https://doi.org/10.3334/CDIAC/atg.db1001" target="_blank">https://doi.org/10.3334/CDIAC/atg.db1001</a>)
Uno spettacolo a misura dei “particolari”: “Con chi vengo vengo” a palazzo Girifalco (Napoli 1665)
En el año 1665 el palacio del duque de Girifalco acoge a unos nobles napolitanos seleccionados para exhibir su magnificencia y su lealtad a la corona de España con un espectáculo muy rico sobre la obra de Calderón “Con quien vengo vengo”. Esta ocasión atestigua el mito de Calderón en Nápoles a lo largo del siglo XVII y las técnicas representativas en las casas aristocráticas. El texto fue puesto en escena utilizando las estrategias típicas del teatro napoletano, con prólogos y «licenze» musicales, bailes entre los actos e idiomas múltiples, y entregado a una compañía de valientes diletantes y profesionales talentosos. Entre «mensajes» performativos y otros se celebra una liturgia de propaganda, en la que se encuentran todos los elementos que amplifican y subrayan el homenaje del duque y de sus huéspedes, que se reconocen en él, al poder español. El esplendor y el mito de la «cattolicissima» ciudad se constituye a través de ocasiones parecidas, que unen los lenguajes más diferentes y la experimentación más atrevida. En este tiempo Nápoles anda perfeccionando y definiendo un papel artístico que en unas décadas se convertirá en una primacía absoluta en toda Europa.In 1665 the palace of the Duke of Girifalco hosts a selected group of aristocratic people for a rich performance inspired to Calderón’s “Con quien vengo vengo”, in order to show the magnificence of the house as well as its loyalty to the Spanish king. This event testifies both to the myth of Calderón in Naples in the 17th century and to the performing strategies in private houses. The text was staged using typical resources of Neapolitan theatres, such as prologues, musical insertions, dances between the acts and multiple language scenes, and was entrusted to a troupe formed by talented amateurs and skilled practitioners. Technical solutions and other «messages» constitute a propagandistic «liturgy» aimed at emphasizing the tribute of the Duke (and of his entourage) to the Spanish power. The glamour and the myth of the «catholic» nation is based also upon such events, where different «languages» and bold experiments are combined. At that time Naples is gaining (and bringing to perfection) an artistic role, which will soon turn into an absolute primacy in Europe
SPARC REport No. 7
peer reviewedThe Montreal Protocol (MP) controls the production and consumption of carbon tetrachloride (CCl4 or CTC) and other ozone-depleting substances (ODSs) for emissive uses. CCl4 is a major ODS, accounting for about 12% of the globally averaged inorganic chlorine and bromine in the stratosphere, compared to 14% for CFC-12 in 2012.
In spite of the MP controls, there are large ongoing emissions of CCl4 into the atmosphere. Estimates of emissions from various techniques ought to yield similar numbers. However, the recent WMO/UNEP Scientific Assessment of Ozone Depletion [WMO, 2014] estimated a 2007-2012 CCl4 bottom-up emission of 1-4 Gg/year (1-4 kilotonnes/year), based on country-by-country reports to UNEP, and a global top-down emissions estimate of 57 Gg/ year, based on atmospheric measurements. This 54 Gg/year difference has not been explained.
In order to assess the current knowledge on global CCl4 sources and sinks, stakeholders from industrial, governmental, and the scientific communities came together at the “Solving the Mystery of Carbon Tetrachloride” workshop, which was held from 4-6 October 2015 at Empa in Dübendorf, Switzerland. During this workshop, several new findings were brought forward by the participants on CCl4 emissions and related science.
• Anthropogenic production and consumption for feedstock and process agent uses (e.g., as approved solvents) are reported to UNEP under the MP. Based on these numbers, global bottom-up emissions of 3 (0-8) Gg/year are estimated for 2007-2013 in this report. This number is also reasonably consistent with this report’s new industry-based bottom-up estimate for fugitive emissions of 2 Gg/year.
• By-product emissions from chloromethanes and perchloroethylene plants are newly proposed in this report as significant CCl4 sources, with global emissions estimated from these plants to be 13 Gg/year in 2014.
• This report updates the anthropogenic CCl4 emissions estimation as a maximum of
~25 Gg/year. This number is derived by combining the above fugitive and by-product emissions (2 Gg/year and 13 Gg/year, respectively) with 10 Gg/year from legacy emissions plus potential unreported inadvertent emissions from other sources.
• Ongoing atmospheric CCl4 measurements within global networks have been exploited for assessing regional emissions. In addition to existing emissions estimates from China and Australia, the workshop prompted research on emissions in the U.S. and Europe. The sum of these four regional emissions is estimated as 21±7.5a Gg/year, but this is not a complete global accounting. These regional top-down emissions estimates also
show that most of the CCl4 emissions originate from chemical industrial regions, and are not linked to major population centres.
• The total CCl4 lifetime is critical for calculating top-down global emissions. CCl4 is destroyed in the stratosphere, oceans, and soils, complicating the total lifetime estimate. The atmospheric lifetime with respect to stratospheric loss was recently revised to 44 (36-58) years, and remains unchanged in this report. New findings from additional measurement campaigns and reanalysis of physical parameters lead to changes in the ocean lifetime from 94 years to 210 (157-313) years, and in the soil lifetime from 195 years to 375 (288-536) years.
• These revised lifetimes lead to an increase of the total lifetime from 26 years in WMO [2014] to 33 (28-41) years. Consequently, CCl4 is lost at a slower rate from the atmosphere. With this new total lifetime, the global top-down emissions calculation decreases from 57 (40-74) Gg/year in WMO [2014] to 40 (25-55) Gg/year. This estimate is relatively consistent with the independent gradient top-down emissions of 30 (25-35) Gg/year, based upon differences between atmospheric measurements of CCl4 in the Northern and Southern Hemispheres. In addition, this new total lifetime implies an upper limit of 3-4 Gg/year of natural emissions, based upon newly reported observations of old air in firn snow.
These new CCl4 emissions estimates from the workshop make considerable progress toward closing the emissions discrepancy. The new industrial bottom-up emissions estimate (15 Gg/year total) includes emissions from chloromethanes plants (13 Gg/year) and feedstock fugitive emissions (2 Gg/year). When combined with legacy emissions and unreported inadvertent emissions, this could be up to 25 Gg/year. Top-down emissions estimates are: global 40 (25-55) Gg/year, gradient 30 (25-35) Gg/year, and regional 21 (14-28) Gg/year. While the new bottom-up value is still less than the aggregated top-down values, these estimates reconcile the CCl4 budget discrepancy when considered at the edges of their uncertainties
Achieved systolic blood pressure in older people: A systematic review and meta-analysis
Background: It remains unclear into which level the systolic blood pressure (SBP) should be lowered in order to provide the best cardiovascular protection among older people. Hypertension guidelines recommendation on attaining SBP levels 33,600 participants) were included. Compared with attaining SBP levels ≥140 mmHg, levels of 130 to <140 mmHg were not associated with lower risk of outcomes in the meta-analysis of RCTs, whereas there was an associated reduction of cardiovascular mortality (RR 0.72, 95% CI 0.59-0.88) and all-cause mortality (RR 0.86, 95% CI 0.75-0.99) in the meta-analysis of post-hoc analyses or subanalyses of RCTs. Limited and conflicting data were available for the SBP levels of <130 mmHg and 140 to <150 mmHg. Conclusions: Among older people, there is suggestive evidence that achieving SBP levels of 130 to <140 mmHg is associated with lower risks of cardiovascular and all-cause mortality. Future trials are required to confirm these findings and to provide additional evidence regarding the <130 and 140 to <150 mmHg SBP levels
Targeting the MET oncogene by concomitant inhibition of receptor and ligand via an antibody-“decoy” strategy
MET, a master gene sustaining "invasive growth," is a relevant target for cancer precision therapy. In the vast majority of tumors, wild-type MET behaves as a "stress-response" gene and relies on the ligand (HGF) to sustain cell "scattering," invasive growth and apoptosis protection (oncogene "expedience"). In this context, concomitant targeting of MET and HGF could be crucial to reach effective inhibition. To test this hypothesis, we combined an anti-MET antibody (MvDN30) inducing "shedding" (i.e., removal of MET from the cell surface), with a "decoy" (i.e., the soluble extracellular domain of the MET receptor) endowed with HGF-sequestering ability. To avoid antibody/decoy interaction-and subsequent neutralization-we identified a single aminoacid in the extracellular domain of MET-lysine 842-that is critical for MvDN30 binding and engineered the corresponding recombinant decoyMET (K842E). DecoyMET(K842E) retains the ability to bind HGF with high affinity and inhibits HGF-induced MET phosphorylation. In HGF-dependent cellular models, MvDN30 antibody and decoyMET(K842E) used in combination cooperate in restraining invasive growth, and synergize in blocking cancer cell "scattering." The antibody and the decoy unbridle apoptosis of colon cancer stem cells grown in vitro as spheroids. In a preclinical model, built by orthotopic transplantation of a human pancreatic carcinoma in SCID mice engineered to express human HGF, concomitant treatment with antibody and decoy significantly reduces metastatic spread. The data reported indicate that vertical targeting of the MET/HGF axis results in powerful inhibition of ligand-dependent MET activation, providing proof of concept in favor of combined target therapy of MET "expedience.
BPGA- an ultra-fast pan-genome analysis pipeline
Recent advances in ultra-high-throughput sequencing technology and metagenomics have led to a
paradigm shift in microbial genomics from few genome comparisons to large-scale pan-genome studies
at different scales of phylogenetic resolution. Pan-genome studies provide a framework for estimating
the genomic diversity of the dataset, determining core (conserved), accessory (dispensable) and
unique (strain-specific) gene pool of a species, tracing horizontal gene-flux across strains and providing
insight into species evolution. The existing pan genome software tools suffer from various limitations
like limited datasets, difficult installation/requirements, inadequate functional features etc. Here we
present an ultra-fast computational pipeline BPGA (Bacterial Pan Genome Analysis tool) with seven
functional modules. In addition to the routine pan genome analyses, BPGA introduces a number of
novel features for downstream analyses like core/pan/MLST (Multi Locus Sequence Typing) phylogeny,
exclusive presence/absence of genes in specific strains, subset analysis, atypical G + C content analysis
and KEGG & COG mapping of core, accessory and unique genes. Other notable features include
minimum running prerequisites, freedom to select the gene clustering method, ultra-fast execution,
user friendly command line interface and high-quality graphics outputs. The performance of BPGA has
been evaluated using a dataset of complete genome sequences of 28 Streptococcus pyogenes strains
Optimal estimation of the surface fluxes of methyl chloride using a 3-D global chemical transport model
Methyl chloride (CH3Cl) [CH subscript 3 Cl] is a chlorine-containing trace gas in the atmosphere contributing significantly to stratospheric ozone depletion. Large uncertainties in estimates of its source and sink magnitudes and temporal and spatial variations currently exist. GEIA inventories and other bottom-up emission estimates are used to construct a priori maps of the surface fluxes of CH3Cl [CH subscript 3 Cl]. The Model of Atmospheric Transport and Chemistry (MATCH), driven by NCEP interannually varying meteorological data, is then used to simulate CH3Cl [CH subscript 3 Cl] mole fractions and quantify the time series of sensitivities of the mole fractions at each measurement site to the surface fluxes of various regional and global sources and sinks. We then implement the Kalman filter (with the unit pulse response method) to estimate the surface fluxes on regional/global scales with monthly resolution from January 2000 to December 2004. High frequency observations from the AGAGE, SOGE, NIES, and NOAA/ESRL HATS in situ networks and low frequency observations from the NOAA/ESRL HATS flask network are used to constrain the source and sink magnitudes. The inversion results indicate global total emissions around 4100 ± 470 Gg yr−1 [yr superscript -1] with very large emissions of 2200 ± 390 Gg yr−1 [yr superscript -1] from tropical plants, which turn out to be the largest single source in the CH3Cl [CH subscript 3 Cl] budget. Relative to their a priori annual estimates, the inversion increases global annual fungal and tropical emissions, and reduces the global oceanic source. The inversion implies greater seasonal and interannual oscillations of the natural sources and sink of CH3Cl [CH subscript 3 Cl] compared to the a priori. The inversion also reflects the strong effects of the 2002/2003 globally widespread heat waves and droughts on global emissions from tropical plants, biomass burning and salt marshes, and on the soil sink.United States. National Aeronautics and Space Administration (Grant NNX07AE89G)United States. National Aeronautics and Space Administration (Grant NAG5-12669)United States. National Aeronautics and Space Administration (Grant NNX07AF09G)United States. National Aeronautics and Space Administration (Grant NNX07AE87G)National Science Foundation (U.S.) (Grant ATM-0120468)United States. National Aeronautics and Space Administration (Grant NAG5-12099
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