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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estudio Hipoglicemiante de Amaranthus powelli S. Watson “atajo”

Loja Herrera, Berta January 2015 (has links)
Objetivo: Determinar la acción hipoglicemiante de Amaranthus powelli S. Watson “atajo” a partir del extracto acuoso, de las hojas en animales de experimentación. Lugar; Facultades: Ciencias Biológicas (Laboratorio de Farmacognosia), Medicina Humana (Laboratorio de Farmacología) y Farmacia y Bioquímica (Laboratorio de Cemprofarma) de la UNMSM. Material y Método: se emplearon 60 ratones machos albinos Mus musculus de la cepa HSDMIH y 84 ratas machos albinas de la especie Rattus novergicus cepa Holtzmann. Método empleado CYTED 1995. Resultados: Taxonómicamente la planta conocida como “atajo” es Amaranthus powelli S. Watson. La DL50 es de 8831,45 mg/Kg. para Amaranthus powelli S. Watson, se observa una reducción de glicemia en ratas sometidas a la prueba oral de glucosa, siendo mayor en los animales que recibieron 100 mg/kg. La planta no es tóxica. Se identificaron los principios activos responsables de la actividad farmacológica, los cuales se determinaron como metabolitos secundarios, el estudio fitoquímico del extracto metanólico y etéreo indican la presencia de taninos, flavonoides, esteroides, triterpenoides y alcaloides. La existencia de cromo y magnesio, se determinó en el análisis de minerales, 2 minerales importantes, el cromo en el metabolismo de la glucosa y el magnesio en la secreción de insulina. El estudio histopatológico en el hígado, bazo y riñones de las ratas demostró que la planta no produce lesión en ellas. Conclusión, el extracto acuoso de las hojas de Amaranthus powelli S.Watson baja el nivel de glucosa, siendo mayor en los animales que recibieron 100 mg/Kg. de extracto.
2

Aplicación de métodos de bioingeniería cutánea en la evaluación de la eficacia de una formulación dermocosmética elaborada a base del aceite de Amaranthus caudatus L. "Kiwicha"

Chapilliquén Llerena, Mabel, Alvis Huamán, Rafael Alberto January 2006 (has links)
El aceite de los granos de Amaranthus caudatus L. “Kiwicha” (Anexo Nº1), se extrajo por el método de Soxhlet y se evaluó: la seguridad cutánea y ocular in vivo aplicando los métodos “Acute Dermal Irritation/Corrosion” (OECD 404) y “Acute Eye Irritation/Corrosion” (OECD 405) de Guidelines for Testing of Chemicals; se determinaron las propiedades físico-químicas del aceite: peso específico, índice de refracción, índice de acidez, índice de saponificación, índice de peróxido, índice de yodo. Se realizó una formulación O/W conteniendo 5% del aceite y se evaluaron las características microbiológicas de la fórmula según la USP 29; se evaluó la eficacia dermocosmética de la fórmula hasta las 24 horas con modernos equipos de Bio-ingeniería Cutánea, evaluando parámetros como: el efecto humectante empleando el Corneometer, la pérdida de agua transepidérmica empleando el Tewameter, los parámetros viscoeláticos de la piel empleando el Cutometer, el microrelieve cutáneo empleando el Visioscan; de los parámetros evaluados se demostró que la formulación que contiene 5% de aceite de Amaranthus caudatus L. “Kiwicha” proporciona a la piel un efecto humectante altamente significativo a través del día, además de brindar otros beneficios cosméticos importantes como son: incremento de la elasticidad, suavidad, atenuación de arrugas y mantenimiento de la eficacia de la función barrera de la piel, todos estos beneficios se atribuyen a la formulación que contiene este aceite. / --- The seed oil of Amaranthus caudatus L. “Kiwicha” (Annex Nº1) was extracted, by the method of Soxhlet and it was evaluated: the cutaneous and ocular in vivo safety of the oil was evaluated applying the methods “Acute Dermal Irritation/Corrosion” (OECD 404) and “Acute Eye Irritation/Corrosion” (OECD 405) of the Guidelines for Testing of Chemicals; the physical-chemical properties of the oil were determined: specific weight, refractive index, acid value, saponification index, peroxide index, iodine index. A formulation O/W containing 5% of the oil was made and it was evaluated the microbiology characteristic according to USP 29; the effectiveness was evaluated until the 24 hours with modern equipment of Cutaneous Bioengineering, the parameters evaluating are: the moisturizing effect using the Corneometer, the Transepidermical Water Loss using the Tewameter, the biomechanical parameters of the skin using the Cutometer, micro relief cutaneous using the Visioscan; of the evaluated parameters is demonstrated that the formulation that contains 5% of seed oil of Amaranthus caudatus L. “Kiwicha” provides to the skin a moisturizing effect highly significant through day, besides to offer other important cosmetic benefits as they are: increase of the elasticity, smoothness, attenuation of wrinkles and maintenance of the effectiveness of the function barrier of the skin, all these benefits are attributed to the formulation that contains this oil.
3

Development and Characterization of Microsatellite Markers for the Grain Amaranths (Amaranthus spp. L.)

Mallory, Melanie Ann 13 July 2007 (has links)
The grain amaranths (Amaranthus hypochondriacus L., A. cruentus L., and A. caudatus L.) are important pseudocereals native to the Americas that have received increased attention for their nutritional content, specifically their balance of amino acids. The objective of this project was to produce and characterize a set of highly informative, reproducible microsatellite markers for the grain amaranths. A total of 1457 clones were sequenced from three genomic libraries enriched for the microsatellite motifs AAC, AAT and AC. Of these, 353 (24%) contained unique microsatellites. An additional 29 microsatellite loci were identified among 728 BAC-end sequences of a newly developed amaranth BAC library. Flanking primers were designed for 319 of the microsatellite loci and all were screened on a panel of diverse amaranths, including grain and weedy Amaranthus species. A total of 179 (56%) microsatellites were polymorphic across accessions from the three grain amaranths. Among these polymorphic microsatellite loci, a total of 731 alleles were identified with average of four alleles per locus. Heterozygosity values ranged from 0.14 to 0.83 with a mean value of 0.62. Thirty-seven (21%) of the markers were polymorphic between the parents of a segregating population and were shown to be inherited in a normal Mendelian fashion based on chi-squared analysis, demonstrating the utility of these markers for linkage mapping of the amaranth genome. Phylogenetic analysis using the marker data showed A. hybridus accessions in two of the three major grain amaranth clades, suggesting the polyphyletic evolution of the three cultivated species from different A. hybridus ancestors. The microsatellite markers reported here will be useful for further evaluating the relationships among the grain amaranths and their relatives and are an ideal resource for use in marker-assisted breeding programs, germplasm analysis and varietal identification. The transferability of these markers to A. hybridus, A. powellii, and A. retroflexus as reported here suggests that the markers may be useful to other species with the genus Amaranthus, including economically important weeds, vegetable amaranths, and ornamentals.
4

Agronomic and physiological aspects of competition for light between corn hybrids differing in canopy architecture and weeds

Begna, Sultan Hussein. January 1999 (has links)
No description available.
5

Aplicación de métodos de bioingeniería cutánea en la evaluación de la eficacia de una formulación dermocosmética elaborada a base del aceite de Amaranthus caudatus L. "Kiwicha"

Alvis Huamán, Rafael Alberto, Chapilliquén Llerena, Mabel January 2006 (has links)
El aceite de los granos de Amaranthus caudatus L. “Kiwicha” (Anexo Nº1), se extrajo por el método de Soxhlet y se evaluó: la seguridad cutánea y ocular in vivo aplicando los métodos “Acute Dermal Irritation/Corrosion” (OECD 404) y “Acute Eye Irritation/Corrosion” (OECD 405) de Guidelines for Testing of Chemicals; se determinaron las propiedades físico-químicas del aceite: peso específico, índice de refracción, índice de acidez, índice de saponificación, índice de peróxido, índice de yodo. Se realizó una formulación O/W conteniendo 5% del aceite y se evaluaron las características microbiológicas de la fórmula según la USP 29; se evaluó la eficacia dermocosmética de la fórmula hasta las 24 horas con modernos equipos de Bio-ingeniería Cutánea, evaluando parámetros como: el efecto humectante empleando el Corneometer, la pérdida de agua transepidérmica empleando el Tewameter, los parámetros viscoeláticos de la piel empleando el Cutometer, el microrelieve cutáneo empleando el Visioscan; de los parámetros evaluados se demostró que la formulación que contiene 5% de aceite de Amaranthus caudatus L. “Kiwicha” proporciona a la piel un efecto humectante altamente significativo a través del día, además de brindar otros beneficios cosméticos importantes como son: incremento de la elasticidad, suavidad, atenuación de arrugas y mantenimiento de la eficacia de la función barrera de la piel, todos estos beneficios se atribuyen a la formulación que contiene este aceite. / The seed oil of Amaranthus caudatus L. “Kiwicha” (Annex Nº1) was extracted, by the method of Soxhlet and it was evaluated: the cutaneous and ocular in vivo safety of the oil was evaluated applying the methods “Acute Dermal Irritation/Corrosion” (OECD 404) and “Acute Eye Irritation/Corrosion” (OECD 405) of the Guidelines for Testing of Chemicals; the physical-chemical properties of the oil were determined: specific weight, refractive index, acid value, saponification index, peroxide index, iodine index. A formulation O/W containing 5% of the oil was made and it was evaluated the microbiology characteristic according to USP 29; the effectiveness was evaluated until the 24 hours with modern equipment of Cutaneous Bioengineering, the parameters evaluating are: the moisturizing effect using the Corneometer, the Transepidermical Water Loss using the Tewameter, the biomechanical parameters of the skin using the Cutometer, micro relief cutaneous using the Visioscan; of the evaluated parameters is demonstrated that the formulation that contains 5% of seed oil of Amaranthus caudatus L. “Kiwicha” provides to the skin a moisturizing effect highly significant through day, besides to offer other important cosmetic benefits as they are: increase of the elasticity, smoothness, attenuation of wrinkles and maintenance of the effectiveness of the function barrier of the skin, all these benefits are attributed to the formulation that contains this oil.
6

Revisión taxonómica y filogenia de las especies monoicas de Amaranthus L. (Amaranthaceae): Amaranthus subg. Albersia y Amaranthus subg. Amaranthus

Bayón, Néstor D. January 2009 (has links)
El género Amaranthus L. pertenece a la familia Amaranthaceae Juss., tribu Amarantheae Rchb. Fue fundado por Linneo en 1753 y cuenta con 72 especies. Al género Amaranthus se lo ha dividido tradicionalmente en tres subgéneros, a saber: Amaranthus subg. Acnida (L.) Aellen, caracterizado por sus plantas dioicas, Amaranthus subg. Albersia (Kunth) Gren. & Godr., con plantas monoicas e inflorescencias predominantemente en glomérulos axilares (cuando las inflorescencias son terminales sus flores pistiladas presentan tres sépalos o sus frutos son indehiscentes) y Amaranthus subg. Amaranthus, también con plantas monoicas pero en las que predominan las inflorescencias terminales, con cinco sépalos en sus flores pistiladas y frutos dehiscentes. Las especies dioicas del género Amaranthus, esto es Amaranthus subg. Acnida, han sido estudiadas por Sauer. El presente tratamiento se propone por un lado confirmar la monofilia del género Amaranthus y por otro realizar la revisión taxonómica de las especies monoicas del mismo, es decir las pertenecientes a Amaranthus subg. Albersia y Amaranthus subg. Amaranthus, los cuales han sido tratados en estudios parciales pero nunca en forma integral. De las 72 especies totales, 55 son americanas, mientras que las restantes 17 son australianas, africanas o euroasiáticas. Para efectuar este estudio se examinaron cerca de 1000 ejemplares de herbario, de los cuales 75 correspondieron a ejemplares tipo a los que se suman más de 200 imágenes de tipos, todos ellos pertenecientes a 33 de las principales instituciones botánicas del mundo. La revisión taxonómica incluyó el análisis de cerca de 300 nombres específicos y subespecíficos asignados a Amaranthus subg. Albersia y Amaranthus subg. Amaranthus. / Información extraída de <a href="http://www.agro.unlp.edu.ar/index.php?nContent=48">http://www.agro.unlp.edu.ar/index.php?nContent</a>
7

Agronomic and physiological aspects of competition for light between corn hybrids differing in canopy architecture and weeds

Begna, Sultan Hussein. January 1999 (has links)
The problems associated with short growing seasons has led to the development of leafy-reduced stature (LRS) corn hybrids. These hybrids have more leaf area above the ear, more rapid leaf area development, shorter stature, earlier maturity, and better responses to high plant populations and narrow spacings than conventional hybrids. Plants grown in a reduced light environment are limited in carbon assimilation and this, in turn, results in reductions in growth and development. A way to supplement the availability of photosynthate is injection of sucrose into plant stems. The objective of this thesis was to determine the ability of LRS corn plants to compete with weeds, and the reactions of weed species to the shade, including the relationships between weed growth (increase in biomass) and development (shape) under shaded conditions. Three years of field experiments (LRS and more conventional corn hybrids with both transplanted and naturally growing weeds) and two years of greenhouse work [weeds alone, C3 (lamb's quarters and velvetleaf) and C4 (redroot pigweed) in full sun or deep (75%) shade injected with 15% sucrose or not] were conducted. Yield reductions due to weed pressure were lower for LRS than other hybrids. Biomass production by both transplanted and naturally occurring weeds was up to 85% less under corn canopies than when grown without competition from corn. The biomass of C4 weeds was more reduced by competition with corn plants than that of C3 weeds. In spite of quick and early leaf development, leaves and other plant parts of LRS were not damaged excessively by mechanical (rotary hoeing) weed control. Both C3 and C4 weed plants produced more dry matter when injected with sucrose. Dry weights of sucrose injected shaded plants were not different from full sun uninjected plants. However, sucrose injection did not alter shading effects on development (distribution of biomass). Dry matter production and photosynthetic rates of C4 weeds were more reduced
8

WATERHEMP (AMARANTHUS TUBERCULATUS) IN SOYBEAN IN KENTUCKY CONDITIONS

Patton, Blake P 01 January 2013 (has links)
Waterhemp was a sporadic weed in Kentucky soybean production since the 1970’s. Waterhemp’s presence was not significant until the 1990’s after a widespread adoption of imazaquin and imazethapyr herbicides in the late 1980’s by Kentucky farmers which resulted in ALS-resistant waterhemp in some Kentucky areas. The introduction of glyphosate resistant soybeans in 1996 resulted in glyphosate-containing products being widely used by Kentucky farmers. Waterhemp populations resistant to glyphosate have occurred in Kentucky in the past few years. The majority of Kentucky soybeans are produced in some type of conservation tillage system, primarily to conserve soil and water, which is advantageous on Kentucky’s rolling topography. Glyphosate controls a wide range of weeds and popular with farmers because of this characteristic. However, waterhemp resistant to glyphosate developed in some fields with the continuous glyphosate usage. Waterhemp control research trials were conducted in Union and Hancock Counties in Western Kentucky in an attempt to find herbicide combinations to provide season-long control. Waterhemp populations in these studies were resistant and susceptible to glyphosate but the resistant populations were great enough to cause soybean yield loss if not controlled. KEYWORDS: Amaranthus tuberculatus, Herbicide Resistance, EPSPS, PPO, ALS
9

Evaluation of Macrophoma sp. as a potential mycoherbicide for the control of Amaranthus retroflexus L. (redroot pigweed)

Chin, Alice January 1995 (has links)
Amaranthus retroflexus L. (redroot pigweed) is a major weed of many crops in North America including corn, soybean, and potato. It can be readily controlled by chemical and cultural methods. However, some populations of A. retroflexus have developed resistance against the application of triazine herbicides. Biololical control could be an alternative method to control this weed species. In 1990, a Macrophoma sp. causing foliar lesions was isolated from redroot pigweed and the potential of this plant pathogenic fungus as a mycoherbicide was evaluated. Large numbers of infective propagules were produced in solid substrate fermentation with chickpeas. When inoculated with 10$ sp8$ or 10$ sp9$ conidia m$ sp{-2}$, plants at the cotyledon to 2-leaf stage showed the most severe damage. Disease developed over a wide range of dew period durations (6 hr to 24 hr) and temperature regimes (14 C to 26 C), and the most rapid and destructive disease development occurred following a 24-hr dew period at 18 C. In controlled environment studies, this Macrophoma sp. was pathogenic to the genus Amaranthus and the closely related genus Celosia.
10

Evaluation of five lines of amaranth (Amaranthus caudatus) in three locations within the Imbabura province

Dávila Pullas, Lorena Marivel 01 January 2008 (has links)
The following lines of white-seeded amaranth were tested in three locations within the Imbabura province of Ecuador: Ecu-0113, Ecu-0014, Ecu-2210, Ecu-4737, and Ecu-4744. The three locations used were Caranqui, Urcuquí, and Pucará which are 2228, 2423, and 2513 meters above sea level respectively. The objectives of this study were: 1) to identify which of the five experimental amaranth lines respond best at each altitude, 2) to establish which of the three locations is most appropriate for cultivation, 3) to understand the vegetative period of the five lines in each location, 4) to analyze which of the five experimental lines possesses the best characteristics in regard to yield, and 5) to determine the cost of producing one hectare of amaranth. The hypothesis was that at least one of the five amaranth lines has a different response in each of the three locations. A randomized block design with five treatments (varieties) and three repetitions in each location was used. Tests of significance were conducted via the Tukey method at 0.05 examining stem length, panicle length, yield, and days to harvest for all varieties and locations. Combined analysis was used to evaluate variety interaction by location. Significant differences in stem length were observed among the different locations and varieties. The Ecu-0113 variety reached lengths of 1020.00 mm. In regard to panicle length, significant differences were also observed among different locations and varieties. The most promising locations were Urcuquí and Caranqui while the most promising varieties were Ecu-0113 and Ecu-4737. Significant differences in grain yield were also observed among the different locations and varieties. In the Urcuquí area, the Ecu-0113 variety had the highest yield with a yield of 2404.24 kg/ha. In the Caranqui and Pucará areas, the Ecu-2210 variety had the highest yields with values of 1605.88 and 833.99 kg/ha respectively. The Ecu-4744 variety was the first ready to harvest in all three locations while the variety Ecu-2210 was the last. The production of one hectare of amaranth resulted in a cost-benefit ratio of 2.48 which means that for every dollar invested, $1.48 USD was recovered. In the Imbabura province, Urcuquí and Caranqui can be considered favorable environments for cultivation and Ecu-0113 and Ecu-2210 were the varieties that exhibited the greatest production potential. We recommend planting the Ecu-0113 variety in Urcuquí and the Ecu-2210 variety in Caranqui and Pucará to obtain maximum grain yield.

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