The Impact of Future CO2 Emission Reduction Targets on U.S. Electric Sector Water Use

The U.S. electric sector's reliance on water makes it vulnerable to the impacts of climate change on water resources. Here we analyze how constraints on U.S. energy system carbon dioxide (CO2) emissions could affect water withdrawal and consumption in the U.S. electric sector through 2055. We use simulations of the EPA's U.S. 9-region (EPAUS9r) MARKAL least-cost optimization energy systems model with updated water use factors for electricity generating technologies. Model results suggest CO2 constraints could force the retirement of old power plants and drive increased use of low water-use renewable and nuclear power as well as natural gas CCS plants with more advanced cooling systems. These changes in electric sector technology mix reduce water withdrawal in all scenarios but increase water consumption in aggressive scenarios. Decreased electric sector water withdrawal would likely reduce electric sector vulnerability to climate change, but the rise in consumption could increase competition with other users.Master of Scienc

The Synthesis and Fine Structure Studies of Polycyclic Aromatic Hydrocarbons

The main part of this thesis has dealt with benzylic coupling in a large number of methyl derivatives of polycyclic aromatic hydrocarbons. It has been shown previously that a coupling constant of ~1.0 Hz. between the methyl protons and the ortho aromatic proton is indicative of a high degree of localisation and double bond character in the intervening bond. This idea has been extended by examining a series of symmetrical 6-dimethyl derivatives which involved synthesising 2' ,3'-dimethyl-1,2;6,7-dibenzo-pyrene, (I) and 6,7-dimethy1-1,2:3-4-dibenzanthracene (II). 9,10-Dimethyl-3,4-benzotetraphene (III) was obtained as a byproduct in the latter synthesis. The couplings in these derivatives add further evidence to the idea that there is only one true double bond in each ring which occupies the lowest energy orbital. The remaining 4 pi-electrons are divided into two higher energy levels with one pair remaining delocalised within the ring,and the third pair, in the highest level, delocalised outside the ring and capable of migrating from ring to ring. An annellation effect is thus observed in passing from o-xylene to 2,3-dimethylanthracene (IV)(V)(VI) which can be explained by the increased linear annellation reducing the influence of those delocalised pi-electrons which are free to migrate, as they are spread over more rings. The distribution of the true double bond can also be considerably affected by substitution in the ring. This is reflected by considerable -changes in the magnitude of the benzylic coupling and supports the additivity of only one true double bond in each ring. The electronic arrangement in pyridazine is in the opposite sense to naphthalene and anthracene. There is a high degree of double bond character in the 4,5 position and a correspondingly low value in the 3,4 and 5,6 positions. This is borne out on examination of a number of methylpyridazines and adds further evidence to the above ideas. Finally, the unusual asymmetry of the methyl resonance in alpha-methyl derivatives was investigated. During this work an explanation was published on the basis of computer analysis of the methyl signal and it appears that the asymmetry is inherent with this combination of couplings to the ortho, para and meta protons on the ring. The apparent lack of long-range coupling in aromatic hydrocarbons has been attributed to 2nd order interactions. In this work halogen derivatives of anthracene and tetracene were examined. Decoupling indicates the absence of para coupling between the protons on non-terminal rings, although there is substantial trans-peri coupling between the protons of a terminal and non-terminal ring. However a methyl group on a non-terminal ring is found to he strongly coupled only to the para proton with J= 0.8-1.0Hz. This value is as large as the coupling constant observed for the localised double bond in 9-methylphenanthrene 1.0 Hz. This evidence is compared with other methyl derivatives and several possible explanations are discussed. The reductive dimerisation of 6-naphthanthrone yielded the known hydrocarbons, dinaphtho-(7', 1' : 1,13): (1", 7" :6, 8) -peropyrene , dinaphtho- -peropyrene and 2,3-trimethylenepyrene along with two new hydrocarbons (VIl) and(VIIl). Circobiphenyl (VII) is a highly condensed hydrocarbon which can be considered as a double coronene. The U.V. spectrum is similar to coronene, however its low solubility has proved a stumbling block in efforts to obtain the n. m. r. spectrum. It was hoped that the protons of this molecule would resonate at low field thus indicating a "superaromaticity" effect analogous to coronene. A new purple hydrocarbon was also obtained and U.V. evidence favours the structure dibenzisoviolanthrene (VIIl). Application of Robinsons aromatic sextet to this structure does not indicate any localised dienophilic regions and therefore this molecule should not react with maleic anhydride. Contrary to expectations, two-fold addition of maleic anhydride does occur in a similar manner to 2,3:4,5:8,9:10,11-tetrabenzoperylene and on this basis the possibility of structure (IX) cannot be excluded. However closer examination of structure (IX) shows that a complete Kekule structure is not possible, despite the fact that alternant marking predicts an equal number of marked and unmarked carbon atoms. The former finding leads to the theoretical prediction of a diradical or higher structure with an inherent instability as shown by triangulene, yet from the alternant marking sbbeme (IXa) a bond across the middle ring involving electrons of opposite spin might be possible. In order to test the above predictions and to try and clarify the reactivity of the purple hydrocarbon with maleic anhydride, an unambiguous synthesis of (IX) was attempted. A series of examples which show the asymmetric annellation of two diphenyl complexes to an acene have been built up over the years. Two of the remaining members of this series are 1,2:3,4:11,12: 13,14-hetrabenzheptacene (x) and 1,2:3,4-dibenzhexacene (xi). A synthesis of the former compound was undertaken to increase the scope of the above series and in an effort to obtain a reasonably stable heptacene derivative

Sudden cardiac death due to deficiency of the mitochondrial inorganic pyrophosphatase PPA2

We have used whole exome sequencing to identify biallelic missense mutations in the nuclearencoded mitochondrial inorganic pyrophosphatase (PPA2) in ten individuals from four unrelated pedigrees that are associated with mitochondrial disease. These individuals show a range of severity, indicating that PPA2 mutations may cause a spectrum of mitochondrial disease phenotypes. Severe symptoms include seizures, lactic acidosis and cardiac arrhythmia and death within days of birth. In the index family, presentation was milder and manifested as cardiac fibrosis and an exquisite sensitivity to alcohol, leading to sudden arrhythmic cardiac death in the second decade of life. Comparison of normal and mutated PPA2 containing mitochondria from fibroblasts showed the activity of inorganic pyrophosphatase significantly reduced in affected individuals. Recombinant PPA2 enzymes modeling hypomorphic missense mutations had decreased activity that correlated with disease severity. These findings confirm the pathogenicity of PPA2 mutations, and suggest that PPA2 is a new cardiomyopathy-associated protein, which has a greater physiological importance in mitochondrial function than previously recognized

Effect of Hydrocortisone on Mortality and Organ Support in Patients With Severe COVID-19: The REMAP-CAP COVID-19 Corticosteroid Domain Randomized Clinical Trial.

Importance: Evidence regarding corticosteroid use for severe coronavirus disease 2019 (COVID-19) is limited. Objective: To determine whether hydrocortisone improves outcome for patients with severe COVID-19. Design, Setting, and Participants: An ongoing adaptive platform trial testing multiple interventions within multiple therapeutic domains, for example, antiviral agents, corticosteroids, or immunoglobulin. Between March 9 and June 17, 2020, 614 adult patients with suspected or confirmed COVID-19 were enrolled and randomized within at least 1 domain following admission to an intensive care unit (ICU) for respiratory or cardiovascular organ support at 121 sites in 8 countries. Of these, 403 were randomized to open-label interventions within the corticosteroid domain. The domain was halted after results from another trial were released. Follow-up ended August 12, 2020. Interventions: The corticosteroid domain randomized participants to a fixed 7-day course of intravenous hydrocortisone (50 mg or 100 mg every 6 hours) (n = 143), a shock-dependent course (50 mg every 6 hours when shock was clinically evident) (n = 152), or no hydrocortisone (n = 108). Main Outcomes and Measures: The primary end point was organ support-free days (days alive and free of ICU-based respiratory or cardiovascular support) within 21 days, where patients who died were assigned -1 day. The primary analysis was a bayesian cumulative logistic model that included all patients enrolled with severe COVID-19, adjusting for age, sex, site, region, time, assignment to interventions within other domains, and domain and intervention eligibility. Superiority was defined as the posterior probability of an odds ratio greater than 1 (threshold for trial conclusion of superiority >99%). Results: After excluding 19 participants who withdrew consent, there were 384 patients (mean age, 60 years; 29% female) randomized to the fixed-dose (n = 137), shock-dependent (n = 146), and no (n = 101) hydrocortisone groups; 379 (99%) completed the study and were included in the analysis. The mean age for the 3 groups ranged between 59.5 and 60.4 years; most patients were male (range, 70.6%-71.5%); mean body mass index ranged between 29.7 and 30.9; and patients receiving mechanical ventilation ranged between 50.0% and 63.5%. For the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively, the median organ support-free days were 0 (IQR, -1 to 15), 0 (IQR, -1 to 13), and 0 (-1 to 11) days (composed of 30%, 26%, and 33% mortality rates and 11.5, 9.5, and 6 median organ support-free days among survivors). The median adjusted odds ratio and bayesian probability of superiority were 1.43 (95% credible interval, 0.91-2.27) and 93% for fixed-dose hydrocortisone, respectively, and were 1.22 (95% credible interval, 0.76-1.94) and 80% for shock-dependent hydrocortisone compared with no hydrocortisone. Serious adverse events were reported in 4 (3%), 5 (3%), and 1 (1%) patients in the fixed-dose, shock-dependent, and no hydrocortisone groups, respectively. Conclusions and Relevance: Among patients with severe COVID-19, treatment with a 7-day fixed-dose course of hydrocortisone or shock-dependent dosing of hydrocortisone, compared with no hydrocortisone, resulted in 93% and 80% probabilities of superiority with regard to the odds of improvement in organ support-free days within 21 days. However, the trial was stopped early and no treatment strategy met prespecified criteria for statistical superiority, precluding definitive conclusions. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707

Global burden of 369 diseases and injuries in 204 countries and territories, 1990–2019: a systematic analysis for the Global Burden of Disease Study 2019

Background: In an era of shifting global agendas and expanded emphasis on non-communicable diseases and injuries along with communicable diseases, sound evidence on trends by cause at the national level is essential. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) provides a systematic scientific assessment of published, publicly available, and contributed data on incidence, prevalence, and mortality for a mutually exclusive and collectively exhaustive list of diseases and injuries. Methods: GBD estimates incidence, prevalence, mortality, years of life lost (YLLs), years lived with disability (YLDs), and disability-adjusted life-years (DALYs) due to 369 diseases and injuries, for two sexes, and for 204 countries and territories. Input data were extracted from censuses, household surveys, civil registration and vital statistics, disease registries, health service use, air pollution monitors, satellite imaging, disease notifications, and other sources. Cause-specific death rates and cause fractions were calculated using the Cause of Death Ensemble model and spatiotemporal Gaussian process regression. Cause-specific deaths were adjusted to match the total all-cause deaths calculated as part of the GBD population, fertility, and mortality estimates. Deaths were multiplied by standard life expectancy at each age to calculate YLLs. A Bayesian meta-regression modelling tool, DisMod-MR 2.1, was used to ensure consistency between incidence, prevalence, remission, excess mortality, and cause-specific mortality for most causes. Prevalence estimates were multiplied by disability weights for mutually exclusive sequelae of diseases and injuries to calculate YLDs. We considered results in the context of the Socio-demographic Index (SDI), a composite indicator of income per capita, years of schooling, and fertility rate in females younger than 25 years. Uncertainty intervals (UIs) were generated for every metric using the 25th and 975th ordered 1000 draw values of the posterior distribution. Findings: Global health has steadily improved over the past 30 years as measured by age-standardised DALY rates. After taking into account population growth and ageing, the absolute number of DALYs has remained stable. Since 2010, the pace of decline in global age-standardised DALY rates has accelerated in age groups younger than 50 years compared with the 1990–2010 time period, with the greatest annualised rate of decline occurring in the 0–9-year age group. Six infectious diseases were among the top ten causes of DALYs in children younger than 10 years in 2019: lower respiratory infections (ranked second), diarrhoeal diseases (third), malaria (fifth), meningitis (sixth), whooping cough (ninth), and sexually transmitted infections (which, in this age group, is fully accounted for by congenital syphilis; ranked tenth). In adolescents aged 10–24 years, three injury causes were among the top causes of DALYs: road injuries (ranked first), self-harm (third), and interpersonal violence (fifth). Five of the causes that were in the top ten for ages 10–24 years were also in the top ten in the 25–49-year age group: road injuries (ranked first), HIV/AIDS (second), low back pain (fourth), headache disorders (fifth), and depressive disorders (sixth). In 2019, ischaemic heart disease and stroke were the top-ranked causes of DALYs in both the 50–74-year and 75-years-and-older age groups. Since 1990, there has been a marked shift towards a greater proportion of burden due to YLDs from non-communicable diseases and injuries. In 2019, there were 11 countries where non-communicable disease and injury YLDs constituted more than half of all disease burden. Decreases in age-standardised DALY rates have accelerated over the past decade in countries at the lower end of the SDI range, while improvements have started to stagnate or even reverse in countries with higher SDI. Interpretation: As disability becomes an increasingly large component of disease burden and a larger component of health expenditure, greater research and developm nt investment is needed to identify new, more effective intervention strategies. With a rapidly ageing global population, the demands on health services to deal with disabling outcomes, which increase with age, will require policy makers to anticipate these changes. The mix of universal and more geographically specific influences on health reinforces the need for regular reporting on population health in detail and by underlying cause to help decision makers to identify success stories of disease control to emulate, as well as opportunities to improve. Funding: Bill & Melinda Gates Foundation. © 2020 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licens

Measurement of the top quark forward-backward production asymmetry and the anomalous chromoelectric and chromomagnetic moments in pp collisions at √s = 13 TeV

Abstract The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric (d̂ t) and chromomagnetic (μ̂ t) moments have been measured using LHC pp collisions at a center-of-mass energy of 13 TeV, collected in the CMS detector in a data sample corresponding to an integrated luminosity of 35.9 fb−1. The linearized variable AFB(1) is used to approximate the asymmetry. Candidate t t ¯ events decaying to a muon or electron and jets in final states with low and high Lorentz boosts are selected and reconstructed using a fit of the kinematic distributions of the decay products to those expected for t t ¯ final states. The values found for the parameters are AFB(1)=0.048−0.087+0.095(stat)−0.029+0.020(syst),μ̂t=−0.024−0.009+0.013(stat)−0.011+0.016(syst), and a limit is placed on the magnitude of | d̂ t| < 0.03 at 95% confidence level. [Figure not available: see fulltext.

Measurement of t(t)over-bar normalised multi-differential cross sections in pp collisions at root s=13 TeV, and simultaneous determination of the strong coupling strength, top quark pole mass, and parton distribution functions

Peer reviewe

An embedding technique to determine ττ backgrounds in proton-proton collision data

An embedding technique is presented to estimate standard model tau tau backgrounds from data with minimal simulation input. In the data, the muons are removed from reconstructed mu mu events and replaced with simulated tau leptons with the same kinematic properties. In this way, a set of hybrid events is obtained that does not rely on simulation except for the decay of the tau leptons. The challenges in describing the underlying event or the production of associated jets in the simulation are avoided. The technique described in this paper was developed for CMS. Its validation and the inherent uncertainties are also discussed. The demonstration of the performance of the technique is based on a sample of proton-proton collisions collected by CMS in 2017 at root s = 13 TeV corresponding to an integrated luminosity of 41.5 fb(-1).Peer reviewe

Search for Physics beyond the Standard Model in Events with Overlapping Photons and Jets

Results are reported from a search for new particles that decay into a photon and two gluons, in events with jets. Novel jet substructure techniques are developed that allow photons to be identified in an environment densely populated with hadrons. The analyzed proton-proton collision data were collected by the CMS experiment at the LHC, in 2016 at root s = 13 TeV, and correspond to an integrated luminosity of 35.9 fb(-1). The spectra of total transverse hadronic energy of candidate events are examined for deviations from the standard model predictions. No statistically significant excess is observed over the expected background. The first cross section limits on new physics processes resulting in such events are set. The results are interpreted as upper limits on the rate of gluino pair production, utilizing a simplified stealth supersymmetry model. The excluded gluino masses extend up to 1.7 TeV, for a neutralino mass of 200 GeV and exceed previous mass constraints set by analyses targeting events with isolated photons.Peer reviewe

Measurement of b jet shapes in proton-proton collisions at root s=5.02 TeV

We present the first study of charged-hadron production associated with jets originating from b quarks in proton-proton collisions at a center-of-mass energy of 5.02 TeV. The data sample used in this study was collected with the CMS detector at the CERN LHC and corresponds to an integrated luminosity of 27.4 pb(-1). To characterize the jet substructure, the differential jet shapes, defined as the normalized transverse momentum distribution of charged hadrons as a function of angular distance from the jet axis, are measured for b jets. In addition to the jet shapes, the per-jet yields of charged particles associated with b jets are also quantified, again as a function of the angular distance with respect to the jet axis. Extracted jet shape and particle yield distributions for b jets are compared with results for inclusive jets, as well as with the predictions from the pythia and herwig++ event generators.Peer reviewe