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1.
Sensors (Basel) ; 23(3)2023 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-36772469

RESUMEN

The plate load test (PLT) is the most reliable in situ testing for studying the load-settlement behaviour of footings on unsaturated collapsible soils. In these soils, the suction profile is not constant along the depth, and the scale effect between the prototype and footing leads to different suction averages and, consequently, different data. One method to eliminate the effect of soil suction on the test data is to fully saturate the soil prior to the test, which is also recommended at the design process for footing on collapsible soils. However, the inundation process on PLTs is expensive and time-consuming, which makes this procedure difficult to incorporate into engineering practice. This study presents a device that can be attached to flat dilatometer (DMT) to allow local inundation of the soil as part of the in situ test campaign and obtain the DMT-constrained modulus (MDMT) for both natural and inundated conditions. The MDMT presented an average reduction of 56% from natural to inundated condition. This parameter can be used in a model to predict load-settlement curves by DMT data considering the suction influence on this behaviour. The curves obtained from the prediction model were compared to curves determined by PLT conducted under the same in situ conditions. Good agreement was found between the curves predicted by DMT and those measured by PLT for both conditions. The proposed procedure, which uses a device attached to the DMT blade, provides an investigation method to obtain the load-settlement curve under different suction conditions, which can help in the selection and performance prediction of shallow foundations, taking into account suction and collapse phenomenon-related problems.

2.
Anim Reprod ; 19(3): e20210088, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36156883

RESUMEN

This study evaluated the effect of crude protein (CP) reduction in four diets (156, 139, 132, and 127 g Kg-1 DM) maintaining constant metabolizable protein (188 g/day) on the follicular fluid and cumulus-oocyte complexes of mid-lactating Girolando cows. Twenty-two Girolando cows with average of 21.55 ±3.19 L daily milk yield, 105.30 ±22.62 days in lactation and 3.22 ±0.03 body condition score were selected. To reduce CP in diets and maintain constant metabolizable protein, urea and soybean meal were gradually replaced by lignosulfonate-treated soybean meal (SoyPass®, Cargill), resulting in an increase in rumen-undegradable protein and a reduction in rumen degradable protein. A linear and quadratic reduction was observed in the plasma and follicular fluid urea nitrogen concentration following CP reduction, with the most intense reduction occurring in the 127 g Kg-1 DM group (p<0.001). As CP reduced, there was a tendency for a linear increase in the follicular growth rate (P=0.0696), on the number and proportion of viable oocytes (P<0.09), and also a linear increase for the number (P=0.0397) and proportion (P<0.09) of grade I viable oocytes. Plus, there was a linear effect for the number of cumulus oophorus cells. Cows fed with the lowest amount of CP had cumulus-oocyte complexes with higher numbers of cumulus oophorus cells (P=0.0238). Also, the reduction of diet crude protein was followed by a decrease in the probability of oocytes' DNA degradation. In conclusion, the reduction of CP in the diet of mid-lactating Girolando cows, reduces urea nitrogen concentration in both blood plasma and follicular fluid, and, as a consequence, increases the viability of oocytes and the number of cumulus oophorus cells while reducing oocytes' DNA degradation of follicular included cumulus-oocyte complex. The reduction on dietary CP may improve in vivo oocytes' embryo development impacting fertility of lactating dairy cows.

3.
Theriogenology ; 191: 96-101, 2022 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-35973260

RESUMEN

This study aimed to identify the possible advantages of administering butorphanol (BUT), associated with ketamine/xylazine (KX) sedation or not, for semen collection using electroejaculation (EE) in rams. Fifteen rams received four treatments in a cross-over design using a 2 × 2 factorial arrangement. The treatments were 1) control; 2) received KX; 3) received BUT; and 4) received both treatments. The responses to the procedures regarding heart rate, respiratory frequency, and rectal temperature were recorded, glucose and creatine kinase were measured, and semen quality was determined. More pulses were required when BUT was administered (P = 0.0067), but rams vocalized fewer times (P = 0.046). The administration of KX also tended to reduce the respiratory frequency (P = 0.068) and rectal temperature (P = 0.089), with no other effects. The administration of BUT reduced the heart rate (P < 0.0001), and there was an interactive effect between the administration of BUT and time on the heart rate (P < 0.0001), respiratory frequency (P = 0.01), and rectal temperature (P = 0.047). The administration of BUT reduced the heart rate increase immediately after EE (P < 0.0001). The respiratory frequency following EE was greater when BUT was administered (P < 0.0001), but the administration of BUT reduced the rectal temperature at the same time (P = 0.002). Glucose concentration was greater when BUT was administered (P < 0.0001). The only significant effect on the ejaculate characteristics was from the interaction between KX and BUT on sperm concentration (P = 0.004). The administration of KX alone increased sperm concentration (P = 0.035), but when BUT was added to KX, sperm concentration decreased (P = 0.002). Moreover, sperm concentration was greater when only BUT was administered than when KX and BUT were administered simultaneously (P = 0.037). The addition of BUT markedly decreased most negative responses more effectively than sedation with KX alone. In conclusion, BUT appears to be an interesting alternative to reduce the welfare concerns raised by the use of EE in rams; however, its possible effects on the ejaculate characteristics when associated with other anesthesia/sedation drugs require further study.


Asunto(s)
Anestesia , Anestésicos , Ketamina , Anestesia/veterinaria , Animales , Butorfanol/farmacología , Estudios Cruzados , Glucosa , Ketamina/farmacología , Masculino , Semen/fisiología , Análisis de Semen/veterinaria , Ovinos , Oveja Doméstica , Xilazina/farmacología
4.
Theriogenology ; 173: 32-36, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34265698

RESUMEN

The present study aims to evaluate the effect of administering prostaglandin (250 µg cloprostenol) and oxytocin (10 UI) or a GnRH agonist (4.2 µg buserelin acetate) on rams' physiological responses to electroejaculation and the ejaculate's characteristics. The study was performed with a 2 × 2 factorial arrangement, according to whether it used oxytocin and prostaglandin (OXPGF) or GnRH. Therefore, there were four treatments: GControl = saline; GOXPGF = administration of PGF2α and oxytocin; GGnRH = administration of GnRH; administration of GOXPGF + GnRH = GnRH and PGF2α + oxytocin. An interaction between the hormonal treatments in the heart rate occurred: while the heart rate decreased when using OXPGF alone (control: 113.7 bpm vs. GOXPGF: 103.5 bpm, pooled SEM; P = 0.02), it did not modify when applying both treatments simultaneously and administering GnRH (GGnRH: 109.1 bpm vs. GOXPGF + GnRH: 111.5 bpm respectively, pooled SEM = 4.5). The respiratory rate also decreased with the administration of OXPGF (38.7 vs. 46.3 with and without OXPGF, pooled SEM = 10.0, P = 0.003). Administering OXPGF also tended to decrease the temperature (38.77 °C vs. 38.94 °C, with and without OXPGF, respectively, pooled SEM = 0.06; P = 0.056). Blood glucose increased with the administration of OXPGF from 58.7 mg/dL to 62.4 mg/dL (pooled SEM = 1.3, P = 0.014) and varied with time. CK concentrations increased from 641.8 mg/dL to 881.7 mg/dL (pooled SEM = 50.6) with the administration of OXPGF. GnRH administration decreased cortisol concentration from 7.3 ng/mL to 2.1 ng/mL (pooled SEM = 1.4; P = 0.04). The treatments had no effects on the time required for EE, the pulse at which the animals began and ended the ejaculation, or the vocalizations emitted during EE. There were no effects in any evaluated sperm variable. The research concluded that the administration of oxytocin and analogs of PGF2alpha decreased the stress response to electroejaculation, as well as administering GnRH agonist was slightly effective as it only decreased cortisol concentration. Also, these treatments, either alone or combined, did not affect the characteristics of the ejaculate collected.


Asunto(s)
Cloprostenol , Oxitocina , Animales , Dinoprost/farmacología , Eyaculación , Hormona Liberadora de Gonadotropina , Masculino , Oxitocina/farmacología , Ovinos , Oveja Doméstica
5.
Anim Reprod ; 15(1): 71-74, 2018 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-33365098

RESUMEN

Holstein-Gyr crossbred cattle are strategic for dairy systems in tropical countries, since they combine milk yield genetics with adaptability to tropical climate. However, Holstein (Bos taurus) and Gyr (Bos indicus) breeds present remarkable differences regarding reproductive physiology. Brazil stands out as the world's largest user of embryo in vitro production (IVP) in bovine, and the use of this technique is increasing in dairy systems. As Holstein-Gyr crossbreds are important oocyte donors for IVP, the present work aimed at investigating whether increased Gyr or Holstein breed composition influences donor's performance. Sixteen Holstein-Gyr crossbred females presenting increased (HG, 71.4 to 87.5% Holstein; n = 9) or decreased (GH, 40.2 to 46.6% Holstein; n = 7) Holstein composition were submitted to three ovum pick up (OPU) sessions. We observed similar (P = 0.2946) antral follicle count between HG and GH donors (24.8 ± 3.2 vs 29.4 ± 2.8 respectively; mean ± SEM). Groups also display similar morphological oocyte grading (Grade I: 0.1 ± 0.1 vs 0.1 ± 0.1 - P = 0.9680; Grade II: 0.9 ± 0.5 vs 1.9 ± 0.5 - P = 0.1942; Grade III, 4.0 ± 1.2 vs 7.2 ± 1.4 - P = 0.1047, HG vs GH respectively; mean ± SEM). Additionally, the proportion of viable oocyte was similar between HG and GH groups (27.8% vs 31.9%, respectively, P = 0.3500) and oocyte lipid area fraction (6.8% vs 9.5%, respectively; P = 0.1539). Our results indicate that the individual variation has more influence than breed composition of crossbred oocyte donors.

6.
Estud. av ; 30(86): 221-233, 2016.
Artículo en Portugués | LILACS, BVPS | ID: biblio-1546778

RESUMEN

O ensaio procura mostrar como o título e o enredo de "A terceira margem do rio", o célebre conto de Primeiras estórias, de João Guimarães Rosa, podem ser aproximados da noção de "terceiro não excluído", tal como proposta por Immanuel Wallerstein, em artigo sobre Fernand Braudel e Ilya Prigogine. Nessa perspectiva, o conto apontaria para a existência - na vida como na literatura - de um terceiro caminho, que não exclui mas participa dos dois caminhos usualmente apresentados como mutuamente excludentes pelo pensamento binário - tão difícil de ser superado, como o demonstra um fragmento de Adorno e Horkheimer.


This essay seeks to show how the title and the plot of "A terceira margem do rio" [The third bank of the river], the acclaimed short story from the book Primeiras estórias, by João Guimarães Rosa, relate to the notion of "the unexcluded middle," as discussed by Immanuel Wallerstein in an article on Fernand Braudel and Ilya Prigogine. In this perspective, the short story emphasizes the possibility of a third way that does not exclude, and indeed encompass, the two paths that are often presented as mutually exclusive by the binary thinking - a system that is very difficult to surmount, as a fragment by Adorno and Horkheimer shows.


Asunto(s)
Humanos , Cultura , Literatura , Brasil
7.
Biotechnol Bioeng ; 111(11): 2280-9, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24889673

RESUMEN

Deoxyviolacein is a microbial drug with biological activity against tumors, gram-positive bacteria, and fungal plant pathogens. Here, we describe an Escherichia coli strain for heterologous production of this high-value drug from glycerol. Plasmid-based expression of the deoxyviolacein cluster vioABCE was controlled by the araBAD promoter and induction by L-arabinose. Through elimination of L-arabinose catabolism in E. coli, the pentose sugar could be fully directed to induction of deoxyviolacein biosynthesis and was no longer metabolized, as verified by (13) C isotope experiments. Deletion of the araBAD genes beneficially complemented with previously described (i) engineering of the pentose phosphate pathway, (ii) chorismate biosynthesis, (iii) tryptophan biosynthesis, (iv) improved supply of L-serine, (v) elimination of tryptophan repression, and (vi) of tryptophan catabolism. Subsequent screening of the created next-generation producer E. coli dVio-8 identified glycerol as optimum carbon source and a level of 100 mg L(-1) of L-arabinose as optimum for induction. Transferred to a glycerol-based fed-batch process, E. coli dVio-8 surpassed the gram scale and produced 1.6 g L(-1) deoxyviolacein. With straightforward extraction from culture broth and purification by flash chromatography, deoxyviolacein was obtained at >99.5% purity. Biotechnol. Bioeng. 2014;111: 2280-2289. © 2014 Wiley Periodicals, Inc.


Asunto(s)
Antineoplásicos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Glicerol/metabolismo , Indoles/metabolismo , Ingeniería Metabólica/métodos , Redes y Vías Metabólicas/genética , Arabinosa/metabolismo , Clonación Molecular , Eliminación de Gen , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Familia de Multigenes , Plásmidos , Regiones Promotoras Genéticas
8.
Braz. j. microbiol ; 34(supl.1): 45-47, Nov. 2003. tab
Artículo en Inglés | LILACS | ID: lil-389982

RESUMEN

A atividade de mineração do carvão é responsável pela geração de diferentes sub-produtos. Entre esses, está a pirita que acidifica a água e acelera o processo de solubilização de metais. Como conseqüência, o ambiente torna-se ácido e rico em metais pesados, os quais selecionam os microrganismos capazes de sobreviver nestas condições. Esses microrganismos podem, por sua vez, serem empregados como agentes para a biorremediação de áreas contaminadas com metais pesados. No presente trabalho é descrito o isolamento e a caracterização de bactérias, fungos e leveduras resistentes aos metais zinco, níquel e cádmio.

9.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469477

RESUMEN

The coal mining activity is characterized by the generation of large amount of by-products. One of them is pyrite, which tends to acidify the water, solubilizing heavy metals. As a consequence the environment becomes acid and rich in heavy metals, selecting microorganisms able to survive in this condition, which are of great interest as bioremediation agents. This work describes the isolation and characterization of microorganisms from a coal mining area in Santa Catarina. These microorganisms comprised bacteria, fungi and yeasts resistant to zinc, nickel and cadmium.


A atividade de mineração do carvão é responsável pela geração de diferentes sub-produtos. Entre esses, está a pirita que acidifica a água e acelera o processo de solubilização de metais. Como conseqüência, o ambiente torna-se ácido e rico em metais pesados, os quais selecionam os microrganismos capazes de sobreviver nestas condições. Esses microrganismos podem, por sua vez, serem empregados como agentes para a biorremediação de áreas contaminadas com metais pesados. No presente trabalho é descrito o isolamento e a caracterização de bactérias, fungos e leveduras resistentes aos metais zinco, níquel e cádmio.

10.
ABCD (São Paulo, Impr.) ; 12(3/4): 45-53, Jul.-Dec. 1997. ilus, tab
Artículo en Inglés | LILACS | ID: lil-225828

RESUMEN

Encontra-se bem definido o papel dos aloanticorpos HLA no desencadeamento da rejeicao hiperaguda nos transplantes renais. Nos casos dos transplantes hepaticos, assim como nos transplantes cardiacos, permanece controverso o papel de anticorpos pre-formados na sobrevida do enxerto. Realizamos neste estudo extensa revisao da literatura medica recente publicada pelos grandes centros mundiais transplantadores de figado a respeito da importancia do crossmatch e da compatibilidade HLA nos resultados precoces e tardios do transplante de figado. Ainda longe da unanimidade, a compatibilidade imunologica HLA parece exercer influencias nos desempenhos precoce e tardio dos enxertos hepaticos, apesar do avanco dos imunossupressores. Entretanto a baixa incidencia de paciente transplantados com altos titulos de testes de crossmatch positivos, nao altera a sobrevida global das casuisticas analisadas, sendo controversa sua utilizacao como metodo de selecao frente aos custos de seu emprego, mas nao excluindo seu valor como auxiliar na orientacao da imunossupressao precoce e tardia destes pacientes


Asunto(s)
Humanos , Estudios Cruzados , Histocompatibilidad/inmunología , Trasplante de Hígado/inmunología , Donantes de Tejidos/clasificación , Isoanticuerpos/análisis , Especificidad de Anticuerpos/inmunología , Antineoplásicos/inmunología , Antígenos HLA/inmunología , Isoantígenos/análisis , Rechazo de Injerto/inmunología
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