274 research outputs found
Electric-quadrupole and magnetic-dipole contributions to the νâ+νâ band of carbon dioxide near 3.3âŻÂľm
The recent detections of electric-quadrupole (E2) transitions in water vapor and magnetic-dipole (M1) transitions in carbon dioxide have opened a new field in molecular spectroscopy. While in their present status, the spectroscopic databases provide only electric-dipole (E1) transitions for polyatomic molecules (H_{2}O, CO_{2}, N_{2}O, CH_{4}, O_{3}âŚ), the possible impact of weak E2 and M1 bands to the modeling of the Earth and planetary atmospheres has to be addressed. This is especially important in the case of carbon dioxide for which E2 and M1 bands may be located in spectral windows of weak E1 absorption. In the present work, a high sensitivity absorption spectrum of CO_{2} is recorded by Optical-Feedback-Cavity Enhanced Absorption Spectroscopy (OFCEAS) in the 3.3âŻÂľm transparency window of carbon dioxide. The studied spectral interval corresponds to the region where M1 transitions of the ν_{2}+ν_{3} band of carbon dioxide were recently identified in the spectrum of the Martian atmosphere. Here, both M1 and E2 transitions of the ν_{2}+ν_{3} band are detected by OFCEAS. Using recent ab initio calculations of the E2 spectrum of {12}^C^{16}O_{2}, intensity measurements of five M1 lines and three E2 lines allow us to disentangle the M1 and E2 contributions. Indeed, E2 intensity values (on the order of a few 10^{â29} cm/molecule) are found in reasonable agreement with ab initio calculations while the intensity of the M1 lines (including an E2 contribution) agree very well with recent very long path measurements by Fourier Transform spectroscopy. We thus conclude that both E2 and M1 transitions should be systematically incorporated in the CO_{2} line list provided by spectroscopic databases
Impact of population growth and population ethics on climate change mitigation policy
Future population growth is uncertain and matters for climate policy: higher growth entails more emissions and means more people will be vulnerable to climate-related impacts. We show that how future population is valued importantly determines mitigation decisions. Using the Dynamic Integrated Climate-Economy model, we explore two approaches to valuing population: a discounted version of total utilitarianism (TU), which considers total wellbeing and is standard in social cost of carbon dioxide (SCC) models, and of average utilitarianism (AU), which ignores population size and sums only each time periodâs discounted average wellbeing. Under both approaches, as population increases the SCC increases, but optimal peak temperature decreases. The effect is larger under TU, because it responds to the fact that a larger population means climate change hurts more people: for example, in 2025, assuming the United Nations (UN)-high rather than UN-low population scenario entails an increase in the SCC of 85% under TU vs. 5% under AU. The difference in the SCC between the two population scenarios under TU is comparable to commonly debated decisions regarding time discounting. Additionally, we estimate the avoided mitigation costs implied by plausible reductions in population growth, finding that large near-term savings ($billions annually) occur under TU; savings under AU emerge in the more distant future. These savings are larger than spending shortfalls for human development policies that may lower fertility. Finally, we show that whether lowering population growth entails overall improvements in wellbeingârather than merely cost savingsâagain depends on the ethical approach to valuing population
The potential determinants of young people's sense of justice: an international study
This paper uses reports from 13,000 Grade Nine pupils in five countries to examine issues such as whether they were treated fairly at school, trust their teachers and adults in wider society, are willing to sacrifice teacher attention to help others, and support the cultural integration of recent immigrants. Using such reports as âoutcomesâ in a multiâstage regression model, it is clear that they are largely unrelated to schoolâlevel pupil mix variables. To some extent, these outcomes are stratified by pupil and family background in the same way for all countries. However, the largest association is with pupilâreported experience of interactions with their teachers. Teachers appear to be a major influence on young people's sense of justice and the principles they apply in deciding whether something is fair. The paper concludes by suggesting ways in which schools and teachers could take advantage of this finding
On the Possibility of Continuous, Paretian and Egalitarian Evaluation of Infinite Utility Streams
Measuring Group Disadvantage with Inter-Distributional Inequality Indices: A Critical Review and Some Amendments to Existing Indices
A longitudinal study of gene expression in healthy individuals
<p>Abstract</p> <p>Background</p> <p>The use of gene expression in venous blood either as a pharmacodynamic marker in clinical trials of drugs or as a diagnostic test requires knowledge of the variability in expression over time in healthy volunteers. Here we defined a normal range of gene expression over 6 months in the blood of four cohorts of healthy men and women who were stratified by age (22â55 years and > 55 years) and gender.</p> <p>Methods</p> <p>Eleven immunomodulatory genes likely to play important roles in inflammatory conditions such as rheumatoid arthritis and infection in addition to four genes typically used as reference genes were examined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR), as well as the full genome as represented by Affymetrix HG U133 Plus 2.0 microarrays.</p> <p>Results</p> <p>Gene expression levels as assessed by qRT-PCR and microarray were relatively stable over time with ~2% of genes as measured by microarray showing intra-subject differences over time periods longer than one month. Fifteen genes varied by gender. The eleven genes examined by qRT-PCR remained within a limited dynamic range for all individuals. Specifically, for the seven most stably expressed genes (CXCL1, HMOX1, IL1RN, IL1B, IL6R, PTGS2, and TNF), 95% of all samples profiled fell within 1.5â2.5 Ct, the equivalent of a 4- to 6-fold dynamic range. Two subjects who experienced severe adverse events of cancer and anemia, had microarray gene expression profiles that were distinct from normal while subjects who experienced an infection had only slightly elevated levels of inflammatory markers.</p> <p>Conclusion</p> <p>This study defines the range and variability of gene expression in healthy men and women over a six-month period. These parameters can be used to estimate the number of subjects needed to observe significant differences from normal gene expression in clinical studies. A set of genes that varied by gender was also identified as were a set of genes with elevated expression in a subject with iron deficiency anemia and another subject being treated for lung cancer.</p
Summary for policymakers
The Working Group III contribution to the IPCC Fifth Assessment Report (WGIII AR5) provides a comprehensive assessment of all relevant options for mitigating climate change through limiting or preventing greenhouse gas emissions, as well as activities that remove them from the atmosphere.
It draws on scientific literature accepted for publication prior to 4 October 2013. The WGIII Summary for Policymakers was approved at the Twelfth Session of Working Group III, held in Berlin, Germany, from 7 to 11 April, 2014. During the session, the IPCC plenary also accepted the underlying scientific and technical assessment, which stands at 2000 pages, including more than 700 pages of references
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