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Maria Del Carmen Castillo, Fremont Forum Queen Contestant, Ohio (photograph)
No full textMaria Del Carmen Castillo, Fremont Forum Queen Contestant, Ohio
Interview with Maria Guzman and Juan Jesus Lopez
No full textMaria Guzman was born in 1917 in La Laja, Mexico. Juan Jesus Lopez was born in 1921 in El Salado Ranch, Brownsville, Texas.https://scholarworks.utrgv.edu/rgvoralhistories/1176/thumbnail.jp
Interview with Maria Brewster Castillo
No full textMaria Brewster Castillo tells how the Brewster family came from Mississippi or Alabama in covered wagons during the late 1800\u27s. Her father was a Texas Ranger. Her family always had plenty of food, therefore she never experienced the Great depression.https://scholarworks.utrgv.edu/rgvoralhistories/1063/thumbnail.jp
Student Author- Andres Castillo, March 26, 2024
No full textFayetteville State University student author Andres Castillo speaks at the Chesnutt Library of Fayetteville State University about his book My Life Journey with Autism as a Military Child.
Presented live on March 26, 2024 as part of Chesnutt Library\u27s Faculty Author Series.https://digitalcommons.uncfsu.edu/faculty_author/1006/thumbnail.jp
Construyendo la libertad: género, domesticidad y desigualdad en tiempos de abolición, Buenos Aires, 1813-1840
No full textEn esta investigación he profundizado las relaciones y cruces entre esclavitud, emancipación y mundo del trabajo urbano, en la ciudad de Buenos Aires durante las primeras décadas del siglo XIX. ¿Qué posibilidades tuvieron las mujeres esclavizadas, libertas y libres de negociar o contrarrestar las derivaciones de la condición de esclavitud? Un concepto imprescindible en este trabajo es el de domesticidad que no se explica en el sentido burgués de las clases medias y altas que le dan ese espacio a la mujer en su propia casa, sino la "domesticidad" en el sentido de que la mujer negra trabaja en armarle la domesticidad a otros. Mi hipótesis sostiene que mientras se abandonaba la esclavitud se construía domesticidad y si bien la primera quedó abolida en 1860, la segunda continuó fuertemente identificada principalmente a la mujer negra doméstica-madre-esclava-criadora. La investigación realiza una contribución al desarrollo de un campo específico de estudios que se está delineando en los años recientes y que promete significativas novedades para que podamos conocer mejor la historia de sus clases trabajadoras: se trata de los estudios del mundo del trabajo urbano y en particular del trabajo de las mujeres a lo largo del siglo XIX.Fil: Guzman, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani". Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani"; Argentin
Brønsted acid sites location and thermal stability of NH4-exchanged omega zeolite
No full textDue to their structural features, e.g., the pore system which highly affects their selectivity, acid zeolites are considered of great importance as catalysts in cracking processes of oil refining (isomerization and hydrocarbons cracking). Catalytic activity of acid zeolites depends on the presence of the so-called Brønsted acid sites, i.e., protons bonded to framework oxygen atoms. In order to evaluate their catalytic efficiency, the determination of nature, density, strength and location of Brønsted sites is of particular relevance. Since hydrocarbons catalysts are employed at high temperature, and their molecular sieve features as well as sorptive and catalytic properties are enhanced by heating, the thermal stability of those compounds must be accurately investigated. Zeolitic catalysts characterization through X-ray and neutron diffraction at non-ambient conditions is one of the best analytic tool to prove both their efficiency and stability and characterize their shape selectivity.
In this contribution, a NH4-form omega zeolite was characterized to disclose the presence of acid sites and investigate temperature induced modifications. The as-synthesized omega zeolite (a mazzite analogue with formula Na6.6TMA1.8(H2O)22.2[Al8.4Si27.6O72]-MAZ) was previously studied by Martucci et al., 2003. Its NH4-exchanged form (Na2.4TMA0.9(H2O)4.2(NH4)20 [Al8.4Si27.6O72] was obtained through cationic exchange at Room Temperature (RT) and at 90°C, 3-times each. Powder patterns were collected at the GILDA-BM8 Beamline (ESRF) from RT to 900 °C (heating rate: 5°C/min) and at the D2B Beamline (ILL) at 4 K, and Rietveld refinements were performed through the GSAS-EXPGUI package. Obtained results clearly show: 1) a progressive TMA template and NH4 release induced by the heating process; 2) a NH4 migration highlighted by O–O shortening and T–O–T variations within 6MR, 8MR units and the gmelinite cage which progressively become more distorted on heating. Such structural deformation is particularly highlighted by 1) the variation of T–O2–T angles (i.e., progressive shift of O2 framework oxygen towards the centre of gmelinite cage; and 2) a decreasing of O1–O2 bond distances (due to Brønsted acid sites formation on O2 oxygen atom). Moreover, neutron refinements revealed a disordered Si–Al distribution within tetrahedral sites with a preferential occupation of Al3+ for the T2 site with respect to T1. Although non-reversible framework modifications occur, all the information here gained reveal the omega zeolite as performing hydrocarbons catalyst even at high temperature: indeed, it is stable up to 700°C.
Martucci, A., Alberti, A., de Lourdes Guzman-Castillo, M., Di Renzo, F., & Fajula, F. 2003. Crystal structure of zeolite omega, the synthetic counterpart of the natural zeolite mazzite. Microporous and mesoporous materials, 63(1-3), 33-4
The Family History of Cristhian Guzman
No full textCristhian Guzman authored this family history as part of the course requirements for Your Family in History: HIST 550/700 offered online in Spring 2019 and was submitted to the Pittsburg State University Digital Commons. Please contact the author directly with any questions or comments: [email protected]
La mediación de la raza: complejidades y matices del binomio esclavización y libertad
No full textLa centralidad de la raza como categoría de análisis proporciona claves, hasta ahora poco exploradas, para indagar acerca de cómo ésta ha influido en el desarrollo de los procesos históricos vinculados con la abolición de la esclavitud. Además, bajo qué formas las relaciones formadas en y por la esclavitud persistieron después de la declinación y abolición formal de la misma. Cabe destacar que la categoría de raza no ha sido considerada en los contextos cotidianos ni académicos (con excepción de quienes focalizan en la cuestión racial) cuanto ha sido subsumida por la clase como marcador principal de conflicto y estratificación social. En el caso particular de Argentina, la percepción generalizada de que este país constituye una excepción regional, donde la ausencia de raza y el dinamismo de clase funcionan como emblemas de una modernidad precoz, hacen que sea especialmente importante interrogarse sobre la forma en que las relaciones raciales y coercitivas de la esclavitud configuraron el desenvolvimiento social y laboral de los sujetos descendientes de africanos. ¿Hasta qué punto las ideologías de inclusión racial y la retórica de la igualdad presentes durante el desarrollo de la abolición trascendieron sus historias coloniales de esclavitud y desigualdad racial?Fil: Guzman, Maria Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani". Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Historia Argentina y Americana "Dr. Emilio Ravignani"; ArgentinaFil: Ghidoli, María de Lourdes. Universidad de Buenos Aires. Facultad de Filosofía y Letras; Argentin
Entrevista a Carmen Castillo
No full textEntrevistadores: Maria Josep Balsach Peig i Imma Merino Serrat. Enregistrament i edició vídeo: Anna Bayó DuranEntrevista a la cineasta i guionista xilena Carmen Castillo Echeverría4166.mp4
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Klinckowstroemia cristinae Villegas-Guzman, Pérez & Reyes-Castillo, 2009, sp. nov.
No full textKlinckowstroemia cristinae sp. nov. Material examined. Holotype. Ƥ (CNAC 006649), Hidalgo, Mexico, 2 km Federal highway Crucero- Tianguistengo (20 ° 40.413 ' N, 98 ° 40.255 ' W), 2,080 m, 23 September 2006, pine-oak forest, from Odontotaenius zodiacus, O. Francke, A. Valdez and H. Montaño coll. Paratypes. 3 Ƥ (CNAC 006650- CNAC 006652), 2 33 (CNAC 006653, CNAC 006654), same data as holotype, from two specimens of Odontotaenius zodiacus; 1 Ƥ (CNAC 006655), Hidalgo, Mexico, 2 km Federal highway Crucero- Tianguistengo (20 ° 40.413 ' N, 98 ° 40.255 ' W), 2,080 m, 23 September 2006, pine-oak forest, from Oileus rimator, O. Francke, A. Valdez and H. Montaño coll. Holotype, three paratype females and two paratype males deposited in the CNAC, one female paratype deposited in NMNH. Female (n = 5). Body oval. Idiosoma, L = 928 (928–1005), W = 672 (672–710) (Fig. 21 A). Ve n tr al idiosoma. Hyaline hood extending to level of coxa I, seta a 1 long and slightly serrated (Fig. 23 A), L = 34 (32–38). Tritosternum base wider than long. Tetartosternum shield (Fig. 22 D), L = 43 (40–43), anterior W = 115 (115–124); shagreened, anterior margin slightly concave, medial notch small, triangular. Sternal seta st 1 moderately long, slightly serrated (Fig. 22 E), L = 20 (20–25), near centre of shield; lyriform sternal pore stp 1 close to posterior margin of shield. Sternal shield, L = 81 (81–93) shagreened. Pore stp 2 near anterior margin of shield, behind and below it is sternal seta st 2, medium length and simple, L = 19 (12–19). Setae st 3 long, slightly serrated, L = 28 (25–37), st 4 is medium length, slightly serrated, L = 16 (16–25). Setae st 3 and st 4 towards sides of shield, close to posterior margin (Fig. 22 C). Sternogynial shield, L = 62, W = 171 (164– 186) triangular, posterior margin pointed at apex, surface shagreened, stp 3 near anterior margin (Fig. 21 A). Sternogynial apodeme long and thin, extending to posterior level of latigynial and mesogynial condyles. Latigynial shields (Fig. 22 C), L = 124 (124–140), W= 78 (74–78) each with an oval pore and three or four simple setae, usually four; medial margins of shields straight and short, shield are shagreened; latigynial apodeme long and thin. Mesogynial shield, L = 74 (71–78), W = 99 (93–102), triangular, wider posteriorly and anteriorly (Fig. 22 C), rounded at apex, surface shagreened, mesogynial condyles below level of shield apex. Ventral shield, L = 245 (245–264), posterior W = 531 (512–557), triangular, truncated posteriorly (Fig. 22 F), surface shagreened, reticulated like a honey-comb (Fig. 22 G), with 12–14 pairs of small setae, usually 14. One pore underneath posterior margin of coxa IV. Metapodal-peritremal-exopodal shield reticulated, with a pore, with two setae. Anal shield, L = 161 (155–177), anterior W = 448 (435–480), with six pairs of simple setae plus longer antero anal seta, L = 29 (29–33), shield shagreened, with two pairs of pores, one near anterior margin and the other below the anus. Gnathosoma. Capitular setae (sc) medium and simple, L = 16 (12–17). Hypostomal setae hyp 1 longest and simple, L = 66 (65–71). Seta hyp 2 long and barbed, 40 (40–45), hyp 3 moderately long and simple, L = 19 (16–19). Chelicera with barbed seta, movable digit with four teeth, two large and two small, fixed digit with five teeth, all similar in size, movable finger divided at the tip. Palpal setae are generally simple, but al 1 (av 1) and al 2 (av 2) on trochanter are branched and serrate respectively. Femur setae pv 1 serrated, al 2, ad 1 and ad 2 barbed. Genu setae al 1 and al 2 are barbed, pl 1 and ad 1 are serrated. Anterior margin of palp trochanter with a blunt process (b) and process (s) (Fig. 22 H). Legs. Most leg setae simple, except: Leg I: trochanter ad 1, al 1 and pv 1 serrated; femur pv 1, pv 2 and pv 3 serrated; genu al 1, av 1 and pv 1 serrated; tibia ad 1, ad 2, ad 3, pd 1 and pd 3 serrated. LegII: femur av 1 and pv 1 serrated; genu av 1 and pv 1 serrated. Leg III: trochanter pv 1 slightly serrated; femur av 1 serrated; genu av 1 and pv 1 serrated; tibia ad 3 serrated. Leg IV: trochanter pl 1 slightly serrated; femur av 1 serrated; genu av 1 and pv 1 serrated; tibia ad 3 barbed. Seta pv 1 is serrated and long, 26 (26–30). Male (n = 3) Body oval, similar to female. Idiosoma, L = 966–1011, W = 698–717 (Fig. 21 B). Ve n tr al idiosoma. Tetartosternum (Tst), L = 47–53, anterior W = 124–127, shagreened (Fig. 23 D), anterior margin concave as in female. Tetartosternal notch small, V-shaped and divides anterior margin in two parts, shield with a pore near posterior margin. Sternal seta st 1, L = 22–25, slightly serrated. Sternal shield shagreened (Fig. 23 B), L = 143–149. Setae st 2, st 3 and st 4, microseta simple; shield with two pores, one near anterior margin of the shield, one below coxa IV. Genital opening oval, L = 62, W= 87–90. Ventral shield, L = 372, posterior W= 544–557; shagreened and reticulated as in female, 34 setae (Fig. 21 B); with two pores, one near anterior margin of coxa IV and one below of coxa IV. Anal shield shagreened, L = 171–177, anterior W = 454; with six pairs of simple setae plus longer antero anal aa seta, L = 31–34, with two pores, one near anterior margin and one below anus. Metapodal-peritremal-exapodal shield reticulated, with a pore, without setae. Gnathosoma. Hypostomal setae (Fig. 23 C), hyp 1 long and simple, L = 65–71, hyp 2 serrated and long, L = 43–47, hyp 3 simple and medium length, L = 19. Etymology. This specific name cristinae is named in honour of Mrs. Cristina Olvera for her hospitality and kindness in hosting the senior author during this research. Remarks. This species can be distinguished from all others because the anterior margin of the tetartosternum shield is concave in both sexes, and sternal seta st 3 is the longest and is slightly serrated. The mesogynial shield is long and wider posteriorly; the latigynial shield is long with the medial margins reduced, all the shields are shagreened, except the ventral shield, which is reticulated. The male has st 2, st 3 and st 4 microsetae and simple; the ventral shield is reticulated and shagreened, and the other shields are only shagreened. The tetartosternal notch is small and V-shaped, and the ventral shield has 34 pairs of simple setae. Klinckowstoemia cristinae is similar to K. schusteri because they have three to four simple setae on the latigynial shield, hyp 2 and hyp 3 are serrated and long and moderatly long respectively, in both species. However, the new species is smaller (idiosoma 953.6 versus 1374), has sternal seta st 3 (29.2) long and slightly serrated, and has shagreened sternogenital shields. In comparison, K. schusteri has several shields reticulated (sternal, sternogynial, mesogynial and latigynial) and st 3 (8) small and simple. Both species have large latigynial shields but that of K. cristinae has reduced medial margins (19.5) compared with K. schusteri. The passalids carrying this species were found in decaying trunks in the same locality at Hidalgo, Mexico, on two hosts, Odontotaenius zodiacus and Oileus rimator. Mites were found in the alcohol, but on O. zodiacus we found a male of K. cristinae on coxa I. On O. rimator we found two other species of klinckowstroemiids, K. scotti and K. cristinae.Published as part of Villegas-Guzman, Gabriel A., Pérez, Tila M. & Reyes-Castillo, Pedro, 2009, New species of the genus Klinckowstroemia Baker & Wharton from Mexico (Acari: Mesostigmata: Trigynaspida: Klinckowstroemiidae), pp. 1-46 in Zootaxa 2248 on pages 40-42, DOI: 10.5281/zenodo.19071
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