Systematic errors in global air-sea CO2 flux caused by temporal averaging of sea-level pressure

International audienceLong-term temporal averaging of meteorological data, such as wind speed and air pressure, can cause large errors in air-sea carbon flux estimates. Other researchers have already shown that time averaging of wind speed data creates large errors in flux due to the non-linear dependence of the gas transfer velocity on wind speed (Bates and Merlivat, 2001). However, in general, wind speed is negatively correlated with air pressure, and a given fractional change in the pressure of dry air produces an equivalent fractional change in the atmospheric partial pressure of carbon dioxide (<i>p</i>CO_2air). Thus low pressure systems cause a drop in <i>p</i>CO_2air, which together with the associated high winds, promotes outgassing/reduces uptake of CO₂ from the ocean. Here we quantify the errors in global carbon flux estimates caused by using monthly or climatological pressure data to calculate <i>p</i>CO_2air (and thus ignoring the covariance of wind and pressure) over the period 1990?1999, using two common parameterisations for gas transfer velocity (Wanninkhof, 1992 (W92) and Wanninkhof and McGillis, 1999 (WM99)). Results show that on average, compared with estimates made using 6 hourly pressure data, the global oceanic sink is systematically overestimated by 7% (W92) and 10% (WM99) when monthly mean pressure is used, and 9% (W92) and 12% (WM99) when climatological pressure is used

Correlations in nuclear energy recurrence relations

The excitation energies of states belonging to the ground state bands of heavy even-even nuclei are analysed using recurrence relations. Excellent agreement with experimental data at the 10 keV level is obtained by taking into account strong correlations which emerge in the analysis. This implies that the excitation energies can be written as a polynomial of maximum degree four in the angular momentum.Comment: 4 pages, 1 figure, 1 table, 9 reference

New Keck Observations of Lithium in Very Metal-poor Stars

Lithium abundances have been determined in more than 100 metal-poor halo stars both in the field and in clusters. From these data we find trends of Li with both temperature and metallicity and a real dispersion in Li abundances in the Spite Li plateau. We attribute this dispersion primarily to Li depletion (presumably due to extra mixing induced by stellar rotation) and to Galactic chemical evolution. We derive a primordial Li of 2.44 $\pm$0.18 for A(Li)$_p$ = log N(Li/H) + 12.00. This agrees with the Li abundances predicted by the $WMAP$ results. For stars cooler than the Li plateau we have evidence that Li depletion sets in at hotter temperatures for the higher metallicity stars than for the low-metal stars. This is the opposite sense of predictions from stellar models. The smooth transition of the Li content from the Li plateau stars to the cool stars adds weight to the inference of Li depletion in the plateau stars.Comment: Invited talk for IAU Symposium 228 "From Lithium to Uranium..." held in Paris in May, 2005. 6 pages, 6 figure

Postsynaptic α1-Adrenergic vasoconstriction is impaired in young patients with vasovagal syncope and is corrected by nitric oxide synthase inhibition

BACKGROUND: Syncope is a sudden transient loss of consciousness and postural tone with spontaneous recovery; the most common form is vasovagal syncope (VVS). During VVS, gravitational pooling excessively reduces central blood volume and cardiac output. In VVS, as in hemorrhage, impaired adrenergic vasoconstriction and venoconstriction result in hypotension. We hypothesized that impaired adrenergic responsiveness because of excess nitric oxide can be reversed by reducing nitric oxide. METHODS AND RESULTS: We recorded cardiopulmonary dynamics in supine syncope patients and healthy volunteers (aged 15-27 years) challenged with a dose-response using the α1-agonist phenylephrine (PE), with and without the nitric oxide synthase inhibitor N(G)-monomethyl-L-arginine, monoacetate salt (L-NMMA). Systolic and diastolic pressures among control and VVS were the same, although they increased after L-NMMA and saline+PE (volume and pressor control for L-NMMA). Heart rate was significantly reduced by L-NMMA (P<0.05) for control and VVS compared with baseline, but there was no significant difference in heart rate between L-NMMA and saline+PE. Cardiac output and splanchnic blood flow were reduced by L-NMMA for control and VVS (P<0.05) compared with baseline, while total peripheral resistance increased (P<0.05). PE dose-response for splanchnic flow and resistance were blunted for VVS compared with control after saline+PE, but enhanced after L-NMMA (P<0.001). Postsynaptic α1-adrenergic vasoconstrictive impairment was greatest in the splanchnic vasculature, and splanchnic blood flow was unaffected by PE. Forearm and calf α1-adrenergic vasoconstriction were unimpaired in VVS and unaffected by L-NMMA. CONCLUSIONS: Impaired postsynaptic α1-adrenergic vasoconstriction in young adults with VVS can be corrected by nitric oxide synthase inhibition, demonstrated with our use of L-NMMA

Wit

A brilliant and respected university professor, known for her teaching of the difficult and metaphysical poems of John Donne, is diagnosed with terminal cancer. Throughout the course of her experimental treatments, she comes to an understanding of her work, and her life, with profound humor. Winner of the 1999 Pulitzer Prize for Drama, the New York Times called Wit (sometimes written W;t) a “brutally human and beautifully layered new play…you feel both enlightened and, in a strange way, enormously comforted.” Presented in an intimate staging atmosphere, WIT is sure to move you.https://digitalcommons.cedarville.edu/theatre_productions/1034/thumbnail.jp

Tuesdays with Morrie

Tuesdays with Morrie is the autobiographical story of the friendship of Mitch Albom, an accomplished journalist, and Morrie Schwartz, his former college professor. Sixteen years after graduation, Mitch happens to catch Morrie\u27s appearance in a televised interview and learns that his former professor is battling Lou Gehrig\u27s disease. When Mitch reconnects with Morrie, what begins as a simple visit develops into a weekly pilgrimage and one last class in the meaning of life. Together with Mitch Albom, acclaimed American playwright Jeffrey Hatcher has faithfully adapted the story for performance, capturing all the resonance of the original dialogue and bringing to the stage two of the most genuine and honest characters the theatre has seen in a long time. Described by the New York Daily News as a touching, life-affirming, deeply emotional drama with a generous dose of humor ... and by The New York Times as making the language of the book crisper, cleverer, and more palatable ..., the play will end the Cedarville University season with a warm and thought-provoking commentary on the gift of everyday life.https://digitalcommons.cedarville.edu/theatre_productions/1015/thumbnail.jp

Alice in Wonderland

This 1921 adaptation of the classic fantasy tale by Lewis Carroll tells the story of Alice, a little girl who finds adventure when she enters the world located on the other side of the mirror. In this magical world, Alice encounters numerous amazing characters such as the White Rabbit, the Queen of Hearts, the Gryphon and Mock Turtle, the Mad Hatter and the March Hare, and Tweedle Dee and Tweedle Dum. After experiencing many exciting, and sometimes harrowing, interactions with these nonsensical creatures, Alice returns safely home to muse on the meaning of life as a huge chess game in which individuals seek self-identity and try to make sense of the world. The gentle message of the story is that while the prospect of approaching adulthood can be scary, it is ultimately a rewarding and exciting adventure.https://digitalcommons.cedarville.edu/theatre_productions/1019/thumbnail.jp

Mode superposition in multi-degree of freedom systems using earthquake response spectrum data

Dynamic responses of a series of typical three-degree of freedom structures to strong-motion earthquake excitation were calculated by analog computer techniques and were compared with approximate responses obtained by a superposition of individual modes derived from response spectrum curves. The results indicate that a suitably weighted average of the sum of the absolute values of the individual modes and the square root of the sum of the squares of the modes will give a practical design criterion for the base shear forces in multi-story buildings. For critical designs, this weighted average reduces to the absolute sum of the modes, which is found to be close to the true value for a significantly high proportion of typical earthquake-structure combinations