7,327 research outputs found
Effects of White Chicken Eggshell Powder on Compressive Strength, Water Solubility, and Setting Time of Calcium-Enriched Mixture
Introduction: The present study aimed to evaluate the effects of adding chicken eggshell powder (CESP) to calcium-enriched mixture (CEM) cement on its compressive strength (CS), solubility, and setting time. Materials and Methods: In this study, CESP was added at weight percentages of 3% and 5% to the powder component of the CEM cement. To measure the CS, a total of 36 samples (height, 6 mm; diameter, 4 mm) were tested in a universal testing machine. The setting time was assessed for 18 disk-shaped samples (diameter, 10 mm; height, 1 mm). Additionally, solubility test was performed on 18 samples (diameter, 8 mm; height, 1 mm) after 24 hours, 72 hours, seven days, and 14 days under dehydration conditions by calculating the weight changes; the results were then subjected to a normality test. Next, for the comparison of different test groups, parametric ANOVA test and post-hoc Tukey’s multiple comparison test were performed at a significance level of 0.05. Results: The addition of 5% CESP to the CEM cement significantly reduced its setting time and water solubility (P=0.02 and P=0.01, respectively). Moreover, it significantly increased the CS over a 21-day period (P<0.001). Additionally, the addition of 3% CESP also resulted in a significant increase in CS (P<0.001). While 3% CESP reduced setting time and water solubility, the difference was not statistically significant. Conclusion: The findings suggest that the addition of 5% CESP to CEM cement has the potential to improve its sealing ability, durability, and ability to withstand chewing forces in endodontic treatments. These results highlight the relevance of CESP as an additive for cement modifications and indicate its potential clinical implications
A short proof of some recent results related to Ces{\`a}ro function spaces
We give a short proof of the recent results that, for every the Ces{\`a}ro function space is not a dual space, has the
weak Banach-Saks property and does not have the Radon-Nikodym property.Comment: 4 page
Interpolation of Ces{\`a}ro sequence and function spaces
The interpolation property of Ces{\`a}ro sequence and function spaces is
investigated. It is shown that is an interpolation space between
and for and with , where or
. The same result is true for Ces{\`a}ro sequence spaces. On the other
hand, is not an interpolation space between and
.Comment: 28 page
A case of intersex occurrence in Steindachneridion parahybae (Steindachner, 1877) (Siluriformes: Pimelodidae) under captivity condition: A cytogenetic and morphological study
Poco se sabe sobre la biología reproductiva de Steindachneridion parahybae , una especie de teleósteo gonocorístico en peligro de extinción que habita la cuenca del río Paraíba do Sul y en éste trabajo se describe por primera vez la aparición de individuo intersexo en juvenil de S. parahybae . También se describió el aspecto normal de los ovarios y de los testículos de individuos juveniles procedentes del mismo lote de cría para su comparación; se realizó además el análisis citogenético. Un espécimen fue clasificado a priori como hembra debido a las características macroscópicas de los ovarios, con pequeños oocitos amarillos, sin flecos (característica principal de los bagres macho) y más grande que los testículos; sin embargo el análisis microscópico reveló la presencia de un ovotestis, incluyendo una espermatogénesis completa. S. parahybae presentó un número diploide, 2n = 56 cromosomas, sin evidencia de cromosomas sexuales diferenciados o supernumerarios entre ellos. Estos hallazgos pueden deberse al resultado de la exposición de los individuos a desorganizadores endocrinos o estar influenciados por las condiciones ambientales. Sin embargo no se puede descartar la posibilidad de la presencia de intersexos de forma espontánea. Por lo tanto, la importancia funcional y las consecuencias reproductivas de estas anomalías permanecen aún sin ser determinadas, sugiriendo que esta especie puede ser susceptible a los disruptores endocrinos. Estos resultados contribuyen a ampliar el conocimiento de la biología reproductiva de esta especie en peligro de extinción en condiciones de cautiverio.Little is known about reproductive biology of endangered Steindachneridion parahybae , a gonochoristic teleost species inhabiting the Paraíba do Sul River Basin, and herein is the first description of intersex in S. parahybae juvenile. The normal appearance of ovaries and testes in juvenile from the same lot of breeding were also described for comparison, even as cytogenetic analysis was performed in these juveniles. One specimen was a priori classified as female due to the macroscopic characteristic of ovaries, with small yellow oocytes, without fringes (a main characteristic of catfish male), and larger than testes; however the microscopic analysis revealed the presence of ovotestes, including the complete spermatogenesis. S. parahybae had diploid number, 2n = 56 chromosomes with no evidence of differentiated sex chromosomes or supernumerary chromosomes among them. These findings may be due to the result of exposure to endocrine disrupting compounds or may also be influenced by environmental conditions. The possibility of intersexes might also happen spontaneously and it cannot be ruled out. Therefore, the functional significance and reproductive consequences of this anomaly remain to be determined, suggesting that this species may be susceptible to endocrine disruption. These results contribute to gain expertise about reproductive biology of an endangered species in captivity.Fil: Honji, Renato Massaaki. Universidade de Sao Paulo; Brasil. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Caneppele, Danilo. Companhia Energética de São Paulo. Unidade de Hidrobiologia e Aquicultura; BrasilFil: Pandolfi, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Lo Nostro, Fabiana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Biodiversidad y Biología Experimental y Aplicada. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Biodiversidad y Biología Experimental y Aplicada; ArgentinaFil: Moreira, Renata G.. Universidade de Sao Paulo; Brasi
Finite temperature Dicke phase transition of a Bose-Einstein condensate in an optical cavity
Dicke model predicts a quantum phase transition from normal to superradiant
phases for a two-level atomic ensemble coupled with an optical cavity at zero
temperature. In a recent pioneer experiment [Nature 464, 1301 (2010)], such a
phase transition has been observed using a Bose-Einstein condensate (BEC) in an
optical cavity. Compared with the original Dicke model, the experimental system
features finite temperature and strong atom-photon nonlinear interaction in
BEC. In this Letter, we develop a finite temperature theory for the Dicke phase
transition of a BEC in an optical cavity, taking into account the atom-photon
nonlinear interaction. In addition to explaining the experimentally observed
transition from normal to superradiant phases at finite-temperature, we point
it out that a new phase, the coexistence of normal and superradient phases, was
also observed in the experiment. We show rich finite temperature phase diagrams
existing in the experimental system by tuning various experimental parameters.
We find that the specific heat of the BEC can serve as a powerful tool for
probing various phases.Comment: 5 pages, 5 figure
The Cesàro space of Dirichlet series and its multiplier algebra
We consider the space H(cesp)of all Dirichlet series whose coefficients belong to the Cesàro sequence space cesp, consisting of all complex sequences whose absolute Cesàro means are in p, for 1 1/q}, where 1/p +1/q=1.Ministerio de Economía y Competitividad MTM2015-65888-C4-1-
Piracicaba river basin : mechanical and chemical erosion
It was carried out the characterization of the mechanical and chemical erosive processes in the Piracicaba River basin, for the period 1992-1996, in terms of the fluvial transport of dissolved and particulate materials. The mechanical erosion was calculated from the suspended sediment transport in the basin, considering the surface runoff discharge and the respective concentration calculated taking in account the statistical hydrogram separation method employed. The specific physical degradation calculated for the Piracicaba River basin was 90 t/km2.a, which correspond the velocity of the soil thickness reduction of about 64 m/Ma. The dissolved load of Piracicaba River was corrected due to the influence of the atmospheric inputs, mainly for SO4 2-, Ca2+ and Mg2+ (79.6; 63.8 and 41.8%, respectively). After the input corrections, it was estimated the total atmospheric/soil CO2 consumed during the silicate weathering (229 x 103 moles/km2.a) and the total chemical erosion (16.6 t/km2.a) expressed in terms of the total dissolved solids transported in the basin. The velocity of the silicate rock profile reduction (2.8 m/Ma) was calculated by the fluvial transport of dissolved silica knowing the mean silica concentrations in the parent rock and in the soil profile
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