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1
artículo
Publicado 2018
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The climatic origin of astronomically induced sedimentary cycles in the Mediterranean and adjacent areas during the late Neogene and Quaternary remains puzzling; as cycles have been linked to concomitant but seasonally opposite changes in African summer monsoon precipitation (Eastern Mediterranean sapropels) and Atlantic regulated winter-precipitation (carbonate cycles on the Atlantic side of the Mediterranean). Particularly, little is known about the cyclic sedimentation on orbital time scales in the Western Mediterranean, with the prime exception of the Messinian sapropels from the Sorbas basin (southern Spain). Here we show that regular alternations in Pliocene downhole logs from the industrial drill-site Muchamiel-1, located along the Balearic Promontory in the Western Mediterranean, are related to eccentricity (bundles) and to obliquity and precession cycles (basic meter-scale alter...
2
artículo
Publicado 2014
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The present study aimed the adaptation of the Driving Log, a questionnaire that assesses aggressive and risky driving behaviors in a day by day basis, with 395 Spanish participants. Confirmatory factor analysis showed that the questionnaire fitted properly in two correlated factors, labeled as Risky Driving and Aggressive Driving. Subsequent analyses showed that the number of drives is significantly associated to Risky Driving, while the number of occasions in which anger is experimented correlated with Risky Driving as well as Aggressive Driving. Other findings suggest that men behave in a more risky and aggressive mannerthan women. Young people follow this same tendency in comparison to their elders.
3
artículo
Publicado 2014
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The present study aimed the adaptation of the Driving Log, a questionnaire that assesses aggressive and risky driving behaviors in a day by day basis, with 395 Spanish participants. Confirmatory factor analysis showed that the questionnaire fitted properly in two correlated factors, labeled as Risky Driving and Aggressive Driving. Subsequent analyses showed that the number of drives is significantly associated to Risky Driving, while the number of occasions in which anger is experimented correlated with Risky Driving as well as Aggressive Driving. Other findings suggest that men behave in a more risky and aggressive mannerthan women. Young people follow this same tendency in comparison to their elders.
4
tesis de maestría
Publicado 2017
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The attenuation coefficient slope (ACS) has the potential to be used for tissue characterization and as a diagnostic ultrasound tool, hence complementing B-mode images. The ACS can be valuable for estimation of other ultrasound parameters such as the backscatter coefficient. There is a well-known tradeoff between the precision of the estimated ACS values and the data block size used in spectral-based techniques such as the spectral log difference (SLD). This trade-off limits the practical usefulness of spectral-based attenuation imaging techniques. In this thesis work, the regularized spectral log difference (RSLD) technique is presented in detail and evaluated with simulations and experiments with physical phantoms, ex vivo and in vivo. The ACS values obtained when using the RSLD technique were compared to the ones obtained when using the SLD technique, as well as the ground truth ACS v...
5
tesis de maestría
Publicado 2017
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The attenuation coefficient slope (ACS) has the potential to be used for tissue characterization and as a diagnostic ultrasound tool, hence complementing B-mode images. The ACS can be valuable for estimation of other ultrasound parameters such as the backscatter coefficient. There is a well-known tradeoff between the precision of the estimated ACS values and the data block size used in spectral-based techniques such as the spectral log difference (SLD). This trade-off limits the practical usefulness of spectral-based attenuation imaging techniques. In this thesis work, the regularized spectral log difference (RSLD) technique is presented in detail and evaluated with simulations and experiments with physical phantoms, ex vivo and in vivo. The ACS values obtained when using the RSLD technique were compared to the ones obtained when using the SLD technique, as well as the ground truth ACS v...
6
tesis de maestría
Publicado 2017
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The attenuation coefficient slope (ACS) has the potential to be used for tissue characterization and as a diagnostic ultrasound tool, hence complementing B-mode images. The ACS can be valuable for estimation of other ultrasound parameters such as the backscatter coefficient. There is a well-known tradeoff between the precision of the estimated ACS values and the data block size used in spectral-based techniques such as the spectral log difference (SLD). This trade-off limits the practical usefulness of spectral-based attenuation imaging techniques. In this thesis work, the regularized spectral log difference (RSLD) technique is presented in detail and evaluated with simulations and experiments with physical phantoms, ex vivo and in vivo. The ACS values obtained when using the RSLD technique were compared to the ones obtained when using the SLD technique, as well as the ground truth ACS v...
7
artículo
Publicado 2024
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The octanol-water partition coefficient (logP) is a crucial indicator in the study of lipophilicity and cell permeability, making it a recurring molecular descriptor in empirical rules for evaluating a molecule's pharmacokinetics. Siderophores are pharmacologically relevant molecules due to their potential Trojan horse effect; however, two major challenges arise: their molecular weight often exceeds 500 Daltons, and there is a lack of databases containing atomic coordinates of their three-dimensional structures and molecular descriptors. In this work, we have created a database containing the SMILES codes of siderophores, their names, associated microorganisms, molecular descriptors, among other information, which is available in our repository at https://github.com/inefable12/siderophores_database. We have also developed a web page to visualize the 2D and 3D structures (https://siderofo...
8
artículo
The diversity of the family Pythidae (Coleoptera) is summarized for Peru. One genus (Ischyomius Chevrolat) and two species are recorded. Comments are given on classification and distribution of the family, as well as known biology and natural history, the latter based primarily on larval stages. Based on label data from previously examined specimens and from newly collected material, species of Ischyomius appear to be closely associated with several monocot plant families within order Zingerberales. Ischyomius singularis Chevrolat is recorded from Huánuco and Lima, while I. bicolor Champion is known from Loreto and Madre de Dios; specific collection localities are given.
9
artículo
La diversidad de la familia Pythidae (Coleoptera) se resume para Perú. Se registra un género (Ischyomius Chevrolat) y dos especies. Los comentarios se dan sobre la clasificación y distribución de la familia, así como la biología conocida y la historia natural, esto último basado principalmente en etapas larvarias. Basándose en datos de etiquetas de especímenes previamente examinados y de material recién recolectado, las especies de Ischyomius parecen estar estrechamente asociadas con varias familias de plantas monocotiledóneas dentro del orden Zingerberales. Ischyomius singularis Chevrolat se registra para Huánuco y Lima, mientras I. bicolor Champion es conocido para Loreto y Madre de Dios; se dan localidades de recolección específicas.
10
artículo
Publicado 2013
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El presente trabajo consiste en el levantamiento de columnas estratigráficas y el cartografiado geológico de las diferentes partes del abanico aluvial ubicado sobre la Quebrada Cueva. Con la finalidad de describir e interpretar los procesos geológicos que dieron origen a formas topográficas similares en otras partes de la provincia de Lima.
11
artículo
Publicado 2013
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This survey consist of the field work, mainly focused at the development of sedimentary logs, as well as the field observations of the bulk of the processes that give rise to the different parts of an alluvial fans. This study tackles from sedimentology and cartography skills for unveiling the key physical processes involved at the genesis of similar topographic shapes in Lima province surroundings.
12
artículo
Publicado 2016
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En el nororiente de la Amazonía peruana todavía existen áreas con escasa información sobre primates, siendo una de ellas el interfluvio entre los ríos Napo-Putumayo, lo que motivó la conducción de este estudio para determinar su diversidad y abundancia, así como identificar las amenazas para sus poblaciones. Para este propósito se realizaron censos por transectos en octubre del 2007, setiembre del 2013 y noviembre del 2014 en tres sitios de muestreo. En 1040 km de transectos recorridos fueron observados 308 grupos pertenecientes a nueve especies, siendo Leontocebus nigricollis el más común (109 grupos) y Alouatta seniculus el más escaso (16 grupos). Grupos más pequeños de Lagothrix lagothricha lagothricha (8-11 individuos) y A. seniculus (3-5 individuos) fueron observados en Tamboryacu considerado como el sitio de muestreo de mayor perturbación. Asimismo, la densidad pobla...
13
artículo
Publicado 2016
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Within the northeastern Peruvian Amazonia remain areas with scarce information on primates, one of them being the interfluvium between the Napo and Putumayo rivers. This lack of information motivated us to conduct a study to determine the diversity and abundance of primates within the area, as well as to identify the threats, which inhibit these primate species populations. For this purpose, we conducted transect censuses in three sampling sites in October 2007, September 2013 and November 2014. In 1040 km of transect walks we observed 308 groups of nine primate species, the most common being Leontocebus nigricollis (109 groups) and the rarest being Alouatta seniculus (16 groups). Smaller groups of Lagothrix lagothricha lagothricha (8-11 individuals) and A. seniculus (3-5 individuals) were observed in Tamboryacu, a majorly disturbed sampling site. Likewise, the lowest population densitie...
14
tesis de grado
Publicado 2023
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Gestionar el Registro Técnico de Vuelo (RTV) físicamente implica el transporte constante entre las áreas que intervienen en el proceso de vuelo. Los documentos pueden desde extraviarse e impedir realizar la siguiente etapa del proceso que significa riesgos económicos hasta poner en peligro la vida de las personas. El grupo oficial de documentos tiene validez solo en su versión original, tener copia de los documentos no es óptimo pues debe mantenerse actualizado con la información real y fidedigna, lo que implica arriesgar la información de muchos registros, así como una compleja carga de datos físicos para todos los operarios del proceso. Se requería contar con la información a disposición en cualquier momento, por ello se optó por una aplicación móvil con posibilidad de operar fuera de línea. Todo ello de la mano de una aplicación web que permita el control y administr...
15
artículo
Publicado 2018
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The authors are grateful to the “Ministerio de Educación del Perú” from the Peruvian government for Carmen M.S Ambrosio M.Sc. scholarship, granted by the program “Programa Nacional de Becas y Crédito Educativo” (PRONABEC). Also, the author thanks CIENCIACTIVA for the recent Carmen M.S. Ambrosio Ph.D. scholarship, from the “Consejo Nacional de Ciencia, Tecnología e Inovación Tecnológica” (CONCYTEC-Peru; Contract 278-2015-FONDECYT).
16
artículo
Publicado 2000
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The synthesis of Bis[1,1-diethyl-benzoylthioureathe]lead(II)complex, Pb[PhCONCSNEt2]2 and has been characterized by elementary analysis and IR spectra; the complex has a global formula C24H30ON2S2Pb with number of coordination 4; as well as, binding is double-toothed, coordinating by oxygen and sulphur. In the aquo-dioxane system, has been determined the acid constan! of 1, 1-diethyl-3-benzoylthioureathe ligand, Ka=9,31*1O^(-10), pKa=9,03 with ionic force of the dissolution μ=0.2, contributed by the ionic salt of KHN03 . The constan! of stability of the Bis[1, 1-diethylbenzoilthioureathe]lead(II), Pb[PhCONCSN(Et)2]2, K1= 2,35x10^(-6) ; K2=1,17x10^(6), logB1=6,37; logB2=12,44 through the semi-ñ method.
17
artículo
Publicado 2000
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The synthesis of Bis[1,1-diethyl-benzoylthioureathe]lead(II)complex, Pb[PhCONCSNEt2]2 and has been characterized by elementary analysis and IR spectra; the complex has a global formula C24H30ON2S2Pb with number of coordination 4; as well as, binding is double-toothed, coordinating by oxygen and sulphur. In the aquo-dioxane system, has been determined the acid constan! of 1, 1-diethyl-3-benzoylthioureathe ligand, Ka=9,31*1O^(-10), pKa=9,03 with ionic force of the dissolution μ=0.2, contributed by the ionic salt of KHN03 . The constan! of stability of the Bis[1, 1-diethylbenzoilthioureathe]lead(II), Pb[PhCONCSN(Et)2]2, K1= 2,35x10^(-6) ; K2=1,17x10^(6), logB1=6,37; logB2=12,44 through the semi-ñ method.
18
artículo
Publicado 1999
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This is a famous problem from the annals of literature in operations research. G. Dantzig in [1] refers to W.W. Jacobs with his paper "The Caterer Problem" Nav. Log Res. Quart. 1 1954; as well as Gaddum, Hoffman and Sokolowsky "On the Solution of the Caterer Problem" Naval Res Logist. Quart., Vol.1, No. 3, september, 1954, and William Prager "On the Caterer Problem" of Management Sci, Vol 3, No. 1 october 1956 and Management Sci, Vol 3, No. 2 january 1957. Subsequently both G. Hadley presents the subject in his "Linear Prograrriming" [2], as Walter Garvin in his Introduction as Linear Programming "presented the topic.
19
artículo
Publicado 1999
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This is a famous problem from the annals of literature in operations research. G. Dantzig in [1] refers to W.W. Jacobs with his paper "The Caterer Problem" Nav. Log Res. Quart. 1 1954; as well as Gaddum, Hoffman and Sokolowsky "On the Solution of the Caterer Problem" Naval Res Logist. Quart., Vol.1, No. 3, september, 1954, and William Prager "On the Caterer Problem" of Management Sci, Vol 3, No. 1 october 1956 and Management Sci, Vol 3, No. 2 january 1957. Subsequently both G. Hadley presents the subject in his "Linear Prograrriming" [2], as Walter Garvin in his Introduction as Linear Programming "presented the topic.
20
artículo
Publicado 2004
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The main research objeetive was to determine the effect that proteins and iron have; when they are included in the diet, over bone growing and development in Holztman albino rats 21 days old. They were divided in 4 experimental group: Al ( protein lOg., iron 29mg.), A2 (protein lOg., iron 46mg.), Bl(protein 5g., iron 29mg.), B2 (protein 5g., iron 46mg.) and were sacrificed 46 days after research beginning. There were taken cranium facial Skeleton, mandible and femur measures and they were stained with hemotixilin- eosin, Schiff peryodic acid and Potassic ferrocianurun. Our resuIts show that growing and deve/omen! of rats is directly related with protein and concentration of consumed dieto Weight and length of Craniofacial skeleton,mandible femur as well as number of osteoblasts, osteocites,osteclasts and hemosiderin of A groups were significantly greater in the relation with B groups. Gr...
