Anthropogenic increases in atmospheric greenhouse gas
concentrations are the main driver of current and future climate change. The
integrated assessment community has quantified anthropogenic ...emissions for
the shared socio-economic pathway (SSP) scenarios, each of which represents
a different future socio-economic projection and political environment.
Here, we provide the greenhouse gas concentrations for these SSP scenarios
– using the reduced-complexity climate–carbon-cycle model MAGICC7.0. We
extend historical, observationally based concentration data with SSP
concentration projections from 2015 to 2500 for 43 greenhouse gases with monthly and latitudinal resolution. CO2 concentrations by 2100 range
from 393 to 1135 ppm for the lowest (SSP1-1.9) and highest (SSP5-8.5)
emission scenarios, respectively. We also provide the concentration
extensions beyond 2100 based on assumptions regarding the trajectories of fossil
fuels and land use change emissions, net negative emissions, and the
fraction of non-CO2 emissions. By 2150, CO2 concentrations in the
lowest emission scenario are approximately 350 ppm and approximately plateau
at that level until 2500, whereas the highest fossil-fuel-driven scenario
projects CO2 concentrations of 1737 ppm and reaches concentrations
beyond 2000 ppm by 2250. We estimate that the share of CO2 in the total
radiative forcing contribution of all considered 43 long-lived greenhouse
gases increases from 66 % for the present day to roughly 68 % to 85 % by
the time of maximum forcing in the 21st century. For this estimation,
we updated simple radiative forcing parameterizations that reflect the Oslo
Line-By-Line model results. In comparison to the representative concentration pathways (RCPs), the five main SSPs
(SSP1-1.9, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5) are more evenly spaced
and extend to lower 2100 radiative forcing and temperatures. Performing two
pairs of six-member historical ensembles with CESM1.2.2, we estimate the
effect on surface air temperatures of applying latitudinally and seasonally
resolved GHG concentrations. We find that the ensemble differences in the
March–April–May (MAM) season provide a regional warming in higher northern
latitudes of up to 0.4 K over the historical period, latitudinally averaged
of about 0.1 K, which we estimate to be comparable to the upper bound
(∼5 % level) of natural variability. In comparison to the
comparatively straight line of the last 2000 years, the greenhouse gas
concentrations since the onset of the industrial period and this studies'
projections over the next 100 to 500 years unequivocally depict a
“hockey-stick” upwards shape. The SSP concentration time series derived in
this study provide a harmonized set of input assumptions for long-term
climate science analysis; they also provide an indication of the wide set of
futures that societal developments and policy implementations can lead to –
ranging from multiple degrees of future warming on the one side to
approximately 1.5 ∘C warming on the other.
Climate adaptation by crop migration Sloat, Lindsey L; Davis, Steven J; Gerber, James S ...
Nature communications,
03/2020, Letnik:
11, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Many studies have estimated the adverse effects of climate change on crop yields, however, this literature almost universally assumes a constant geographic distribution of crops in the future. ...Movement of growing areas to limit exposure to adverse climate conditions has been discussed as a theoretical adaptive response but has not previously been quantified or demonstrated at a global scale. Here, we assess how changes in rainfed crop area have already mediated growing season temperature trends for rainfed maize, wheat, rice, and soybean using spatially-explicit climate and crop area data from 1973 to 2012. Our results suggest that the most damaging impacts of warming on rainfed maize, wheat, and rice have been substantially moderated by the migration of these crops over time and the expansion of irrigation. However, continued migration may incur substantial environmental costs and will depend on socio-economic and political factors in addition to land suitability and climate.
Since the classical molecular dynamics simulator LAMMPS was released as an open source code in 2004, it has become a widely-used tool for particle-based modeling of materials at length scales ranging ...from atomic to mesoscale to continuum. Reasons for its popularity are that it provides a wide variety of particle interaction models for different materials, that it runs on any platform from a single CPU core to the largest supercomputers with accelerators, and that it gives users control over simulation details, either via the input script or by adding code for new interatomic potentials, constraints, diagnostics, or other features needed for their models. As a result, hundreds of people have contributed new capabilities to LAMMPS and it has grown from fifty thousand lines of code in 2004 to a million lines today. In this paper several of the fundamental algorithms used in LAMMPS are described along with the design strategies which have made it flexible for both users and developers. We also highlight some capabilities recently added to the code which were enabled by this flexibility, including dynamic load balancing, on-the-fly visualization, magnetic spin dynamics models, and quantum-accuracy machine learning interatomic potentials.
Program Title: Large-scale Atomic/Molecular Massively Parallel Simulator (LAMMPS)
CPC Library link to program files:https://doi.org/10.17632/cxbxs9btsv.1
Developer's repository link:https://github.com/lammps/lammps
Licensing provisions: GPLv2
Programming language: C++, Python, C, Fortran
Supplementary material:https://www.lammps.org
Nature of problem: Many science applications in physics, chemistry, materials science, and related fields require parallel, scalable, and efficient generation of long, stable classical particle dynamics trajectories. Within this common problem definition, there lies a great diversity of use cases, distinguished by different particle interaction models, external constraints, as well as timescales and lengthscales ranging from atomic to mesoscale to macroscopic.
Solution method: The LAMMPS code uses parallel spatial decomposition, distributed neighbor lists, and parallel FFTs for long-range Coulombic interactions 1. The time integration algorithm is based on the Størmer-Verlet symplectic integrator 2, which provides better stability than higher-order non-symplectic methods. In addition, LAMMPS supports a wide range of interatomic potentials, constraints, diagnostics, software interfaces, and pre- and post-processing features.
Additional comments including restrictions and unusual features: This paper serves as the definitive reference for the LAMMPS code.
1S. Plimpton, Fast parallel algorithms for short-range molecular dynamics. J. Comp. Phys. 117 (1995) 1–19.2L. Verlet, Computer experiments on classical fluids: I. Thermodynamical properties of Lennard–Jones molecules, Phys. Rev. 159 (1967) 98–103.
The Solution Cathode Glow Discharge (SCGD) is a novel atmospheric-pressure glow discharge plasma sustained in the ambient atmosphere that is an appealing alternative to the inductively-coupled plasma ...as a source for atomic emission spectrometry. Simple, low power, and inexpensive, the SCGD is an attractive source for continuous environmental monitoring applications such as the quantitation of metallic nanoparticle solutions by atomic emission spectrometry. Metallic nanoparticles (NP) with diameters from 5 nm-150 nm were directly analyzed by SCGD-AES and found to exhibit lower, and size-dependent, elemental sensitivity when compared to dissolved free-ion standard solutions. Acid digestion with matrix-matching was shown to be an effective approach to achieve accurate quantitation. The origin of these morphological matrix effects was studied by investigating experimental parameters such as discharge power, solution flow rate, and influence of added surfactants. Examination of the spatial distribution of atomic emission between cathode and anode showed a shift in peak atomic emission towards the anode of the SCGD for some NPs as compared to free-ion solutions. A novel nested capillary design was used to introduce NP into the SCGD without dissolution within the acidic solvent and showed difference in sensitivity from free-ion solutions to be a NP morphological effect. Correlation of NP boiling point with difference in sensitivity between free-ion and NP solutions supports the conclusion that delayed vaporization of nanoparticles is the source of the morphological matrix effect, due primarily to lower rate of vaporization within the SCGD by lower gas temperatures and short residence time. Analysis of NP of different chemical form, and alloyed nanoparticles composed of more than one element, showed correlation with boiling point. Implications of these results on the possible mechanisms by which material is transferred from the liquid cathode into the plasma are considered.
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•The solution-cathode glow discharge (SCGD) is used for the direct analysis of nanoparticle-containing solutions.•Analytical response of the SCGD to solutions containing nanoparticles is examined with varying experimental parameters.•A nested-capillary design is developed to introduce nanoparticles directly into the SCGD/plasma interface.•Decreased sensitivity of 20%–80% for nanoparticle solutions was seen during the experiment. Sensitivity could be recovered by acid-digestion.•Results are interpreted to gain insights into the potential mechanisms occurring at the interface between the plasma and liquid sample.
Alcohol use disorder (AUD) is a highly prevalent but severely under-treated disorder, with only three widely-approved pharmacotherapies. Given that AUD is a very heterogeneous disorder, it is ...unlikely that one single medication will be effective for all individuals with an AUD. As such, there is a need to develop new, more effective, and diverse pharmacological treatment options for AUD with the hopes of increasing utilization and improving care. In this qualitative literature review, we discuss the efficacy, mechanism of action, and tolerability of approved, repurposed, and novel pharmacotherapies for the treatment of AUD with a clinical perspective. Pharmacotherapies discussed include: disulfiram, acamprosate, naltrexone, nalmefene, topiramate, gabapentin, varenicline, baclofen, sodium oxybate, aripiprazole, ondansetron, mifepristone, ibudilast, suvorexant, prazosin, doxazosin,
N
-acetylcysteine, GET73, ASP8062, ABT-436, PF-5190457, and cannabidiol. Overall, many repurposed and novel agents discussed in this review demonstrate clinical effectiveness and promise for the future of AUD treatment. Importantly, these medications also offer potential improvements towards the advancement of precision medicine and personalized treatment for the heterogeneous AUD population. However, there remains a great need to improve access to treatment, increase the menu of approved pharmacological treatments, and de-stigmatize and increase treatment-seeking for AUD.
A solution-cathode glow discharge (SCGD) using a novel rectangular-shaped cathode capillary is used to study aspects of the plasma-liquid interface. High-speed video of the plasma-liquid interface ...captured simultaneously with low-angle laser scattering from droplets near the plasma-liquid interface are studied in concert to evaluate potential mechanisms related to surface-plasma interaction. Frame-by-frame analysis of high-speed video allows estimation of droplet number density, translational speed, and rate of ejection. The data are evaluated to provide insight into potential mechanisms of analyte transport that are of importance for the use of SCGD in analytical atomic spectrometry.
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•A Rectangular Capillary is Used to Sustain the Solution-Cathode Glow Discharge (SCGD).•High-Speed Video Analysis Reveals Formation of Electrostatic Liquid Jets in Cathode Filaments.•Frame-by-Frame Video Analysis Quantifies Cathode Current Density and Droplet Formation Rate.•The SCGD is Found to Operate at Constant Current Density Independent of Cathode Size.•SCGD Analytical Performance is Improved Using Rectangular Capillary.
The Addictions Neuroclinical Assessment (ANA) was proposed as a neuroscience-informed clinical framework to understand heterogeneity in addiction encompassing dysfunction in three domains: incentive ...salience, negative emotionality, and executive functions. The ANA has been validated in the alcohol field but has not been extended to other substances. Thus, the objective of the current study was to replicate and extend the ANA framework to methamphetamine use disorder. Non-treatment seeking individuals (N = 185) who reported regular methamphetamine use completed a deep phenotyping battery comprising self-report and behavioral measures that assessed methamphetamine craving and emotional withdrawal symptoms, mood and anxiety symptomatology, risk-taking behaviors, working memory, attention, and impulsivity. Factor analytic techniques were used in an iterative manner to derive latent factors that explained biobehavioral variation in the sample. The relationship between factor scores and demographic and clinical indicators of methamphetamine use were examined to assess the construct validity of the latent factors. Deep phenotyping combined with factor analytic techniques implicated three intercorrelated neurofunctional domains that map on to the proposed ANA domains: incentive salience, negative emotionality, and executive function. Each of the domains were associated with demographic and clinical indicators of methamphetamine use providing initial support for their construct validity. The ANA framework holds promise for explaining heterogeneity in addiction by identifying neuroscience-informed phenotypes. Knowledge from the ANA framework may be applied to advance precision medicine and inform medications development for a host of substance use disorders, particularly those with no approved pharmacotherapy such as methamphetamine.
•The Addictions Neuroclinical Assessment (ANA) aims to characterize heterogeneity in addiction.•The ANA framework has been validated in the alcohol field but no other substances.•Deep phenotyping implicated three neurofunctional domains in people who use methamphetamine.•ANA framework may be applied to advance precision medicine for substance use disorders.
To test the hypothesis that law enforcement efforts to disrupt local drug markets by seizing opioids or stimulants are associated with increased spatiotemporal clustering of overdose events in the ...surrounding geographic area.
We performed a retrospective (January 1, 2020 to December 31, 2021), population-based cohort study using administrative data from Marion County, Indiana. We compared frequency and characteristics of drug (i.e., opioids and stimulants) seizures with changes in fatal overdose, emergency medical services nonfatal overdose calls for service, and naloxone administration in the geographic area and time following the seizures.
Within 7, 14, and 21 days, opioid-related law enforcement drug seizures were significantly associated with increased spatiotemporal clustering of overdoses within radii of 100, 250, and 500 meters. For example, the observed number of fatal overdoses was two-fold higher than expected under the null distribution within 7 days and 500 meters following opioid-related seizures. To a lesser extent, stimulant-related drug seizures were associated with increased spatiotemporal clustering overdose.
Supply-side enforcement interventions and drug policies should be further explored to determine whether they exacerbate an ongoing overdose epidemic and negatively affect the nation's life expectancy. (
. 2023;113(7):750-758. https://doi.org/10.2105/AJPH.2023.307291).
Chronic pain affects one in five of the general population and is the third most important cause of disability-adjusted life-years globally. Unfortunately, treatment remains inadequate due to poor ...efficacy and tolerability. There has been a failure in translating promising preclinical drug targets into clinic use. This reflects challenges across the whole drug development pathway, from preclinical models to trial design. Nociceptors remain an attractive therapeutic target: their sensitization makes an important contribution to many chronic pain states, they are located outside the blood-brain barrier, and they are relatively specific. The past decade has seen significant advances in the techniques available to study human nociceptors, including: the use of corneal confocal microscopy and biopsy samples to observe nociceptor morphology, the culture of human nociceptors (either from surgical or post-mortem tissue or using human induced pluripotent stem cell derived nociceptors), the application of high throughput technologies such as transcriptomics, the in vitro and in vivo electrophysiological characterization through microneurography, and the correlation with pain percepts provided by quantitative sensory testing. Genome editing in human induced pluripotent stem cell-derived nociceptors enables the interrogation of the causal role of genes in the regulation of nociceptor function. Both human and rodent nociceptors are more heterogeneous at a molecular level than previously appreciated, and while we find that there are broad similarities between human and rodent nociceptors there are also important differences involving ion channel function, expression, and cellular excitability. These technological advances have emphasized the maladaptive plastic changes occurring in human nociceptors following injury that contribute to chronic pain. Studying human nociceptors has revealed new therapeutic targets for the suppression of chronic pain and enhanced repair. Cellular models of human nociceptors have enabled the screening of small molecule and gene therapy approaches on nociceptor function, and in some cases have enabled correlation with clinical outcomes. Undoubtedly, challenges remain. Many of these techniques are difficult to implement at scale, current induced pluripotent stem cell differentiation protocols do not generate the full diversity of nociceptor populations, and we still have a relatively poor understanding of inter-individual variation in nociceptors due to factors such as age, sex, or ethnicity. We hope our ability to directly investigate human nociceptors will not only aid our understanding of the fundamental neurobiology underlying acute and chronic pain but also help bridge the translational gap.
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