The 1723 AD violent Strombolian and phreatomagatic eruption at Irazu volcano (Costa Rica)

The largest of the recorded historic eruptions at Irazú volcano began on February 16, 1723 and lasted until at least December 11. We here critically examine deposits of this eruption exposed on the summit of Irazú. Our reconstruction of the eruption is based on the unique chronicle of the Spanish governor Diego de la Haya. The eruption began with a < 10 cm thick surge deposit of phreatic origin showing block sag structures. The deposit is overlain by 6 m-thick coarse-grained basaltic andesitic non-graded juvenile fallout tephra consisting of highly vesicular (22-59 vol.%) bombs and lapilli with minor hydrothermally altered lapilli (1-7 vol.%) and rare light colored andesitic vesicular lapilli (< 1%). These fallout deposits are interpreted as strombolian, possible generated during a short-lived scoria cone at the end of February 1723, dominate volumetrically in the proximal facies. Overlying <1.2 m thick phreatomagmatic deposits of fi nely laminated lapilli-bearing gray ash (fallout and surge deposits) some with contorted bedding and sag structures, are in turn overlain by a 1.2 m thick bed of ash matrix-rich bomb/block deposit. The 1723 eruption was accompanied by shallow volcano-tectonic earthquakes (Modifi ed Mercalli scale Intensity MMI VI-VII, magnitude ML ~5.5) that possibly facilitated magma/water interaction. Phenocrysts in the basaltic andesite (~53-55 wt.% SiO2) bombs comprise plagioclase (6.1-21.6 vol.%, An52-35), clinopyroxene (2.5-10 vol.%), orthopyroxene (0.7-2 vol.%), olivine (0.1-2.2 vol.%; Fo76-88) and Fe/Ti-oxides (0.1-1%), in a groundmass (66.5-90.3 vol. %), dominated by plagioclase (An69-54), clinopyroxene and opaques in brown and black glass with the same range of chemical composition (SiO2= 57-64 wt.%). Rare white pumiceous lapilli in the scoria deposits are high-K, hornblende andesite (SiO2: 58-60 wt.%), geochemically unrelated to the scoria deposits. Thus, two different magmas co-existing in the magma chamber were mingled shortly before, and during, the eruption, suggesting that the eruption was triggered by magma mingling between hornblende andesite and basaltic andesite magma

FLORIDA TOMATO MARKET ORDER RESTRICTIONS - AN ANALYSIS OF THEIR EFFECTS AND IMPLEMENTATION

Crop Production/Industries,

RELIGIOUS SYMBOLISM IN AUGUST WILSON’S THE PIANO LESSON

In many of his plays, August Wilson uses religious influences from Africa and from Western Christianity to depict the dichotomy between Black people in America and White people in America. In The Piano Lesson Wilson explores these themes in greater detail and, through an elaborate carving on a piano, shows how the combining of traditional African religions with a westernized version of Christianity can create a uniquely African American experience and expression of religion and spirituality. This thesis discusses the religious integration found in The Piano Lesson and argues that the Charles family ancestors are active agents with decision-making authority regarding the piano, their ancestral burial grounds

Ion homeostasis and variation in low temperature performance in the fall and spring field crickets (Orthoptera: Gryllidae)

Low temperature performance affects the geographical distribution of insects. The lower critical temperature limits of chill-susceptible insects are likely determined by failure of ion and water balance at low temperature. I used phenotypic plasticity in the cold tolerance of Gryllus pennsylvanicus, and the naturally higher cold tolerance of Gryllus veletis to test the hypothesis that variation in low temperature performance is accompanied by variation in ion and water homeostasis at low temperatures. Low temperature acclimation and cold adaptation enhanced performance at low temperatures. Groups with higher cold tolerance had an enhanced ability to prevent or mitigate the migration of hemolymph Na+ and water into the digestive system, which ultimately resulted in smaller decreases in K+ equilibrium potentials at the muscle tissue. The ability to maintain ion and water balance as a result of changes in gut membrane permeability increased performance at low temperatures, and reduced the onset of chilling injury

All-Solid-State Batteries Using Rationally Designed Garnet Electrolyte Frameworks

Functioning bulk-type all-solid-state batteries in a practical form factor with composite positive electrodes, using Al-substituted Li7La3Zr2O12 (LLZO) as the solid electrolyte, have been demonstrated for the first time. The devices incorporate bilayers composed of dense LLZO membranes and porous LLZO scaffolds infiltrated with LiNi0.6Mn0.2Co0.2O2 and other components as positive electrodes, combined with lithium anodes. The porous scaffolds are prepared using an easily scaled freeze-tape-casting method. The unidirectional pores of the scaffold facilitate infiltration of cathode components and shorten lithium ion diffusion path lengths, while the addition of a soft ionically conductive solid to the scaffold ensures good contact among the components

First report of caprine abortions due to Chlamydia abortus in Argentina.

Infectious abortions of goats in Argentina are mainly associated with brucellosis and toxoplasmosis. In this paper, we describe an abortion outbreak in goats caused by Chlamydia abortus. Seventy out of 400 goats aborted. Placental smears stained with modified Ziehl-Neelsen stain showed many chlamydia-like bodies within trophoblasts. One stillborn fetus was necropsied and the placenta was examined. No gross lesions were seen in the fetus, but the inter-cotyledonary areas of the placenta were thickened and covered by fibrino-suppurative exudate. The most consistent microscopic finding was found in the placenta and consisted of fibrinoid necrotic vasculitis, with mixed inflammatory infiltration in the tunica media. Immunohistochemistry of the placenta was positive for Chlamydia spp. The results of polymerase chain reaction targeting 23S rRNA gene performed on placenta were positive for Chlamydia spp. An analysis of 417 amplified nucleotide sequences revealed 99% identity to those of C. abortus pm225 (GenBank AJ005617) and pm112 (GenBank AJ005613) isolates. To the best of our knowledge, this is the first report of abortion associated with C. abortus in Argentina

Efecto del perifiton fijado a substratos artificiales sobre la producción de Penaeus vannamei en cultivo semi-intensivo

En el cultivo de peneidos, la alimentación balanceada representa el mayor costo de producción, este puede variar entre 28% y 50%, y parte de la inversión en estas dietas artificiales puede ser perdida debido a una inadecuada formulación o debido a la baja asimilación. Las partículas de alimento no ingerido y/o no asimilado producen un exceso de materia orgánica que al degradarse forman compuestos como amonio, fosfatos, sulfuros, ácidos orgánicos que generan efluentes excesivamente cargados de nutrientes los cuales causan la eutrofización de las aguas receptoras. En contraste, varios estudios han indicado que los organismos de la productividad acuática natural son de gran valor alimenticio y nutritivo para las especies en cultivo, especialmente para los del género Penaeus por sus hábitos alimenticios, esto podría reducir significativamente los costos de producción y los riesgos de contaminación del agua debido al uso inadecuado de dietas artificiales