Fock space relativistic coupled-Cluster calculations of Two-Valence Atoms

We have developed an all particle Fock-space relativistic coupled-cluster method for two-valence atomic systems. We then describe a scheme to employ the coupled-cluster wave function to calculate atomic properties. Based on these developments we calculate the excitation energies, magnetic hyperfine constants and electric dipole matrix elements of Sr, Ba and Yb. Further more, we calculate the electric quadrupole HFS constants and the electric dipole matrix elements of Sr$^+$, Ba$^+$ and Yb$^+$. For these we use the one-valence coupled-cluster wave functions obtained as an intermediate in the two-valence calculations. We also calculate the magnetic dipole hyperfine constants of Yb$^+$.Comment: 23 pages, 12 figures, 10 tables typos are corrected and some minor modifications in some of the section

A regional ocean circulation model for the mid-Cretaceous North Atlantic Basin: implications for black shale formation

High concentrations of organic matter accumulated in marine sediments during Oceanic Anoxic Events (OAEs) in the Cretaceous. Model studies examining these events invariably make use of global ocean circulation models. In this study, a regional model for the North Atlantic Basin during OAE2 at the Cenomanian-Turonian boundary has been developed. A first order check of the results has been performed by comparison with the results of a recent global Cenomanian CCSM3 run, from which boundary and initial conditions were obtained. The regional model is able to maintain tracer patterns and to produce velocity patterns similar to the global model. The sensitivity of the basin tracer and circulation patterns to changes in the geometry of the connections with the global ocean is examined with three experiments with different bathymetries near the sponges. Different geometries turn out to have little effect on tracer distribution, but do affect circulation and upwelling patterns. The regional model is also used to test the hypothesis that ocean circulation may have been behind the deposition of black shales during OAEs. Three scenarios are tested which are thought to represent pre-OAE, OAE and post-OAE situations. Model results confirm that Pacific intermediate inflow together with coastal upwelling could have enhanced primary production during OAE2. A low sea level in the pre-OAE scenario could have inhibited large scale black shale formation, as could have the opening of the Equatorial Atlantic Seaway in the post-OAE scenario

Manure amendments for mitigation of dairy ammonia and greenhouse gas emissions: preliminary screening

 Amendments can be practical and cost-effective for reducing ammonia [NH3] and greenhouse gas [GHG] emissions from dairy manure.  In this study, the effect of 22 amendments on NH3 and GHG carbon dioxide [CO2], methane [CH4] and nitrous oxide [N2O] emissions from dairy manure were simultaneous investigated at room temperature (20℃).  Dairy manure slurry (2 kg; 1:1.7 urine: feces; 12% total solids) was treated with various amendments, representing different classes of product, following the suppliers’ recommended rates.  In this screening of products, one sample of each amendment was evaluated along with untreated manure slurry with repeated measurements over 24 h.  Gas emissions were measured after short (3 d) and medium (30 d) storage duration using a photoacoustic multi-gas analyzer.  Six amendment products that acted as microbial digest, oxidizing agent, masking agent or adsorbent significantly reduced NH3 by >10% (P = 0.04 to <0.001) after both 3 and 30 d.  Microbial digest/enzymes with nitrogen substrate appeared effective in reducing CH4 fluxes for both storage times.  Most of the masking agents and disinfectants significantly increased CH4 in both storage periods (P = 0.04 to <0.001).  For both CH4 and CO2 fluxes, aging the manure slurry for 30 d significantly reduced gas production by 11 to 100% (P<0.001).  While some products reduced emissions at one or both storage times, results showed that the ability of amendments to mitigate emissions from dairy manure is finite and re-application may be required even for a static amount of manure.  Simultaneous measurement of gases identified glycerol as a successful NH3 reduction agent while increasing CH4 in contrast to a digestive-microbial product that significantly reduced CH4 while enhancing NH3 release.Keywords: methane, greenhouse gas, emission, amendment, additive, dairy manure, ammonia, mitigatio

Evaluation of odor emissions from amended dairy manure: preliminary screening

Manure amendments have shown variable effectiveness in reducing odor.  Twenty-two amendments were applied to dairy manure then evaluated for odor reduction efficacy after storage at 20℃ for 3 d and 30 d.  Amendments represented differing primary modes of action including: microbial digestive, oxidizing, disinfecting, masking, and adsorbent.  Each amendment was added to 2 kg dairy manure (1:1.7 urine:feces; 12% total solids) following recommended rates.  In this preliminary screening, one sample (n=1) of each amendment was evaluated along with untreated manure (Control).  Odor emission from each treated manure and Control was estimated twice by five or six qualified odor assessors (n=10 or 12) after each storage duration, using an international standard for triangular forced-choice olfactometry.  Odor quality was defined using hedonic tone, Labeled Magnitude Scale and ASTM methods for supra-threshold odor intensity, and an odor character wheel for descriptors.  For selected treatments, odor emissions were significantly reduced relative to Control at 30 d versus 3 d incubation (P<0.0001).  However, no amendment was significantly effective for both incubation times.  Likewise, for all amendments tested, aging the manure slurry for 30 d significantly reduced odor emission and odor intensity (P<0.0001).  A proprietary microbial amendment (Alken Enz-Odor + Clear Flo: aerobic/ facultative microbes with growth factors), disinfectant (hydrogen peroxide), and masking agent (Hyssopus officinalis essential oil) provided significant short-term control of odor (P <0.06).  However, after 30 d seven amendments significantly increased odor emission (P<0.02) while only two amendments offered a significant efficacy (P<0.0001): a proprietary microbial aerobic/facultative product (Bio-Regen) and a proprietary mix of chemicals (Greaseater), both with weekly re-application.  Hedonic tone observations suggested an improvement to “slightly to moderately unpleasant” smell versus untreated manure for all amendments except clinoptilolite zeolite adsorbent.  Hedonic tone improvement was correlated with reduced manure odor supra-threshold intensity.Keywords: odor, hedonic tone, odor strength, amendments, additives, dairy manure, United States of Americ

La idiotez y los debates sobre las evaluaciones internacionales a gran escala en las reformas educativas nacionales

Nosotros realizamos una revisión exploratoria de la literatura de investigación y de políticas públicas relativa a las evaluaciones internacionales a gran escala (ILSA en inglés) e hicimos dos encuestas con expertos, creadores de políticas públicas y educadores para entender si, hasta qué punto y cómo tales evaluaciones influenciaron la producción de políticas públicas en el contexto nacional. Nuestra revisión de la literatura confirma que ILSA, con sus usos múltiples y ambiguos, funcionan cada vez más como soluciones idiotas en busca del problema cierto - o sea, parecen ser usadas como herramientas para legitimar reformas educativas. Con "idiotas" no nos referimos al uso común de la palabra, que denota a alguien que no es muy inteligente, sino al significado original de la palabra en griego antiguo, es decir, particular en oposición a perspectivas cívicas o públicas. Los resultados de nuestra encuesta mostraron una percepción creciente entre investigadores, creadores de políticas públicas y educadores, además de otros involucrados, de que las ILSA están teniendo un efecto en las políticas educativas nacionales, visto que más de un tercio (38%) de los entrevistados afirmaron que las ILSA fueron, en general, mal empleadas en los contextos de las políticas públicas nacionales. Sin embargo, mientras que la literatura sobre la ILSA indica que esas evaluaciones están teniendo alguna influencia, hay poca evidencia de que exista una relación causal positiva o negativa entre la participación de la ILSA y la implementación de reformas educativas. Tal vez el cambio más significativo asociado al uso de las ILSA en la literatura que revisamos sea la manera en que nuevas condiciones para la comparación educativa a nivel nacional, regional y global se hicieran posibles

When lingulid brachiopods became infaunal(?) – perspectives from the morphological and anatomical information

Morphology usually serves as an effective proxy for functional ecology, and the evaluation of morphological, anatomical, and ecological changes allows for a deeper understanding of the nature of diversification and macroevolution. Lingulid (Order Lingulida) brachiopods were diverse and abundant during the early Palaeozoic, but decreased in diversity over time, with only a few genera of linguloids and discinoids present in modern marine ecosystems, frequently referred to as âliving fossilsâ. The dynamics that drove this decline remain unclear and it has not been determined if there is an associated decline in morphological and ecological diversity. We applied geometric morphometrics to reconstruct global morphospace occupied by lingulid brachiopods through the Phanerozoic, with results showing that maximum morphospace occupation was reached in the Early Ordovician. At this time of peak diversity, linguloids with sub-rectangular shells already possessed several evolutionary features common to all modern infaunal forms such as the rearrangement of mantle canals and reduction of the pseudointerarea. The end-Ordovician mass extinction had a differential effect on linguloids, disproportionally wiping out those with rounded shells whilst forms with sub-rectangular shells survived both the end-Ordovician and the PermianâTriassic mass extinctions, with post-extinction faunas predominantly composed of infaunal forms. For discinoids, both morphospace occupation and epi-benthic life strategies remain consistent through the Phanerozoic. Analysis of the morphospace occupation of lingulids over time, taking into account their body size, anatomical features and ecological changes, suggests that the reduced morphological and ecological diversity observed in modern lingulid brachiopods reflects evolutionary contingency rather than deterministic processes