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1.
Braz. j. biol ; 83: e249422, 2023. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1339393

RESUMEN

Abstract Ninety days study was conducted in hapas installed in earthen ponds. Fish of an average initial weight (220g) were evenly distributed in triplicate groups within fifteen hapas. Five experimental diets labeled as T1 (25% CP and NRC recommended amino acid level) as control diet, T2 (with 2% low protein and 5% amino acid supplementation), T3 (with 2% low protein and 10% amino acid supplementation), T4 (with 4% low protein and 10% amino acid supplementation) and T5 (with 4% low protein and 20% amino acid supplementation) were prepared. Fish were fed with @3% of their body weight twice a day at 10.00 & 16:00 hour. Significantly higher percent weight gain (420.18 ± 66.84a) and specific growth rate (13499.33±1273.54a) along with improved feed conversion ratio (1.29 ± 0.09b) and hundred percent survivals were recorded during the trial. Furthermore proximate analysis of meat showed significant improvement in the crude protein level (81.77 ± 0.19a) served with diet containing 20% limiting amino acids mixture. Therefore, limiting amino acids can be a source of cost effective feed and use safely in L. rohita diet.


Resumo O estudo de 90 dias foi realizado em hapas instalados em tanques de terra. Peixes com peso inicial médio (220 g) foram distribuídos uniformemente em grupos triplicados em 15 hapas. Cinco dietas experimentais rotuladas como T1 (25% de CP e NRC recomendado nível de aminoácidos) como dieta controle, T2 (com 2% de proteína baixa e 5% de suplementação de aminoácidos), T3 (com 2% de proteína baixa e 10% de suplementação de aminoácidos), T4 (com 4% de baixa proteína e 10% de suplementação de aminoácidos) e T5 (com 4% de baixa proteína e 20% de suplementação de aminoácidos) foram preparadas. Os peixes foram alimentados com 3% do seu peso corporal duas vezes por dia às 10h00 e 16h00. Ganho de peso significativamente maior (420,18 ± 66,84a) e taxa de crescimento específico (13499,33 ± 1273,54a) juntamente com taxa de conversão alimentar melhorada (1, 29 ± 0,09b) e sobrevivência de cem por cento foram registrados durante o ensaio. Além disso, a análise aproximada da carne mostrou melhora significativa no nível de proteína bruta (81,77 ± 0,19a) servida com dieta contendo 20% de mistura de aminoácidos limitantes. Portanto, a limitação de aminoácidos pode ser uma fonte de alimentação econômica e usada com segurança na dieta de L. rohita.


Asunto(s)
Animales , Cyprinidae , Alimentación Animal/análisis , Suplementos Dietéticos , Dieta/veterinaria , Aminoácidos
2.
Braz. j. biol ; 83: 1-8, 2023. tab
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468928

RESUMEN

Ninety days study was conducted in hapas installed in earthen ponds. Fish of an average initial weight (220g) were evenly distributed in triplicate groups within fifteen hapas. Five experimental diets labeled as T1 (25% CP and NRC recommended amino acid level) as control diet, T2 (with 2% low protein and 5% amino acid supplementation), T3 (with 2% low protein and 10% amino acid supplementation), T4 (with 4% low protein and 10% amino acid supplementation) and T5 (with 4% low protein and 20% amino acid supplementation) were prepared. Fish were fed with @3% of their body weight twice a day at 10.00 & 16:00 hour. Significantly higher percent weight gain (420.18 ± 66.84a) and specific growth rate (13499.33±1273.54a) along with improved feed conversion ratio (1.29 ± 0.09b) and hundred percent survivals were recorded during the trial. Furthermore proximate analysis of meat showed significant improvement in the crude protein level (81.77 ± 0.19a) served with diet containing 20% limiting amino acids mixture. Therefore, limiting amino acids can be a source of cost effective feed and use safely in L. rohita diet.


O estudo de 90 dias foi realizado em hapas instalados em tanques de terra. Peixes com peso inicial médio (220 g) foram distribuídos uniformemente em grupos triplicados em 15 hapas. Cinco dietas experimentais rotuladas como T1 (25% de CP e NRC recomendado nível de aminoácidos) como dieta controle, T2 (com 2% de proteína baixa e 5% de suplementação de aminoácidos), T3 (com 2% de proteína baixa e 10% de suplementação de aminoácidos), T4 (com 4% de baixa proteína e 10% de suplementação de aminoácidos) e T5 (com 4% de baixa proteína e 20% de suplementação de aminoácidos) foram preparadas. Os peixes foram alimentados com 3% do seu peso corporal duas vezes por dia às 10h00 e 16h00. Ganho de peso significativamente maior (420,18 ± 66,84a) e taxa de crescimento específico (13499,33 ± 1273,54a) juntamente com taxa de conversão alimentar melhorada (1, 29 ± 0,09b) e sobrevivência de cem por cento foram registrados durante o ensaio. Além disso, a análise aproximada da carne mostrou melhora significativa no nível de proteína bruta (81,77 ± 0,19a) servida com dieta contendo 20% de mistura de aminoácidos limitantes. Portanto, a limitação de aminoácidos pode ser uma fonte de alimentação econômica e usada com segurança na dieta de L. rohita.


Asunto(s)
Animales , Cyprinidae/crecimiento & desarrollo , Cyprinidae/metabolismo , Dieta con Restricción de Proteínas/veterinaria , Dietoterapia/veterinaria
3.
Braz. j. biol ; 832023.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469144

RESUMEN

Abstract Ninety days study was conducted in hapas installed in earthen ponds. Fish of an average initial weight (220g) were evenly distributed in triplicate groups within fifteen hapas. Five experimental diets labeled as T1 (25% CP and NRC recommended amino acid level) as control diet, T2 (with 2% low protein and 5% amino acid supplementation), T3 (with 2% low protein and 10% amino acid supplementation), T4 (with 4% low protein and 10% amino acid supplementation) and T5 (with 4% low protein and 20% amino acid supplementation) were prepared. Fish were fed with @3% of their body weight twice a day at 10.00 & 16:00 hour. Significantly higher percent weight gain (420.18 ± 66.84a) and specific growth rate (13499.33±1273.54a) along with improved feed conversion ratio (1.29 ± 0.09b) and hundred percent survivals were recorded during the trial. Furthermore proximate analysis of meat showed significant improvement in the crude protein level (81.77 ± 0.19a) served with diet containing 20% limiting amino acids mixture. Therefore, limiting amino acids can be a source of cost effective feed and use safely in L. rohita diet.


Resumo O estudo de 90 dias foi realizado em hapas instalados em tanques de terra. Peixes com peso inicial médio (220 g) foram distribuídos uniformemente em grupos triplicados em 15 hapas. Cinco dietas experimentais rotuladas como T1 (25% de CP e NRC recomendado nível de aminoácidos) como dieta controle, T2 (com 2% de proteína baixa e 5% de suplementação de aminoácidos), T3 (com 2% de proteína baixa e 10% de suplementação de aminoácidos), T4 (com 4% de baixa proteína e 10% de suplementação de aminoácidos) e T5 (com 4% de baixa proteína e 20% de suplementação de aminoácidos) foram preparadas. Os peixes foram alimentados com 3% do seu peso corporal duas vezes por dia às 10h00 e 16h00. Ganho de peso significativamente maior (420,18 ± 66,84a) e taxa de crescimento específico (13499,33 ± 1273,54a) juntamente com taxa de conversão alimentar melhorada (1, 29 ± 0,09b) e sobrevivência de cem por cento foram registrados durante o ensaio. Além disso, a análise aproximada da carne mostrou melhora significativa no nível de proteína bruta (81,77 ± 0,19a) servida com dieta contendo 20% de mistura de aminoácidos limitantes. Portanto, a limitação de aminoácidos pode ser uma fonte de alimentação econômica e usada com segurança na dieta de L. rohita.

4.
Front Cell Dev Biol ; 10: 947376, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36060795

RESUMEN

Specification and elaboration of proximo-distal (P-D) axes for structures or tissues within a body occurs secondarily from that of the main axes of the body. Our understanding of the mechanism(s) that pattern P-D axes is limited to a few examples such as vertebrate and invertebrate limbs. Drosophila Malpighian/renal tubules (MpTs) are simple epithelial tubules, with a defined P-D axis. How this axis is patterned is not known, and provides an ideal context to understand patterning mechanisms of a secondary axis. Furthermore, epithelial tubules are widespread, and their patterning is not well understood. Here, we describe the mechanism that establishes distal tubule and show this is a radically different mechanism to that patterning the proximal MpT. The distal domain is patterned in two steps: distal identity is specified in a small group of cells very early in MpT development through Wingless/Wnt signalling. Subsequently, this population is expanded by proliferation to generate the distal MpT domain. This mechanism enables distal identity to be established in the tubule in a domain of cells much greater than the effective range of Wingless.

5.
Rev. habanera cienc. méd ; 21(4)ago. 2022.
Artículo en Español | LILACS, CUMED | ID: biblio-1441928

RESUMEN

Introducción: La heteroforia es la mala alineación de los ejes oculares, que es compensada durante la fijación binocular, al utilizar el mecanismo de fusión. Tiene una alta prevalencia en la población. Objetivo: Evidenciar la importancia de una corrección óptica personalizada en pacientes con heteroforias. Presentación de casos: Se presentan cuatro pacientes que acudieron a consulta de oftalmología, para refracción por presentar síntomas astenópicos. Después de una evaluación completa de cada uno, se constató en todos, la presencia de heteroforia. Se determinó la existencia de exoforia, en tres de ellos, fundamentalmente asociada a insuficiencia de convergencia y esoforia en uno, con exceso de convergencia. Se indicó en todos los casos la corrección óptica personalizada, teniendo en cuenta los resultados de exámenes y se logró la eliminación de las molestias en los pacientes. Conclusiones: Las heteroforias son una causa frecuente de síntomas astenópicos. Es necesario realizar un adecuado estudio, antes de indicar una corrección refractiva, teniendo en cuenta la identificación y cuantificación de la foria, evaluación de las vergencias fusionales, así como estudio del punto próximo de convergencia y la relación convergencia acomodación(AU)


Introduction: Heterophoria is the misalignment of the ocular axes, which is compensated during binocular fixation using the fusion mechanism. It has a high prevalence in the population. Objective: To demonstrate the importance of a personalized optical correction in patients with heterophorias. Cases report: Four cases who attended an ophthalmology consultation for refraction due to asthenopic symptoms are presented. After a complete evaluation of every one of the cases, the presence of heterophoria was found in all of them. The existence of exophoria, mainly associated with insufficient convergence, was determined in three of them; and convergence excess esophoria was identified in one case. Personalized optical correction was indicated in all cases, taking into account the results of the examinations; also, the discomfort in the patients was eliminated. Conclusions: Heterophorias are a frequent cause of asthenopic symptoms. It is necessary to carry out an adequate study before indicating a refractive correction, considering the identification and quantification of phoria, evaluation of fusional vergences, the study of the near point of convergence, and the accommodation-convergence relationship(AU)

6.
Curr Biol ; 32(16): 3545-3555.e4, 2022 08 22.
Artículo en Inglés | MEDLINE | ID: mdl-35853455

RESUMEN

The duplication of genes and their associated cis-regulatory elements, or enhancers, is a key contributor to genome evolution and biological complexity. Moreover, many paralogs, particularly tandem duplicates, are fixed for long periods of time under the control of shared enhancers. However, in most cases, the mechanism by which gene expression and function diverge following duplication is not known. Here, we dissect the regulation and function of the paralogous nubbin/pdm2 genes during wing development in Drosophila melanogaster. We show that these paralogs play a redundant role in the wing and that their expression relies on a single shared wing enhancer. However, the two genes differ in their ability to respond to this enhancer, with nub responding in all wing progenitor cells and pdm2 only in a small subset. This divergence is a result of a pdm2-specific silencer element at the pdm2 promoter that receives repressive input from the transcription factor Rotund. Repression through this silencer also depends on nub, allowing pdm2 to fully respond to the wing enhancer when nub expression is perturbed and functional compensation to occur. Thus, expression divergence downstream of a shared enhancer arises as a consequence of silencing the promoter of one paralog.


Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Animales , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Elementos de Facilitación Genéticos , Regulación del Desarrollo de la Expresión Génica , Alas de Animales
7.
J Exp Bot ; 72(19): 6755-6767, 2021 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-34350947

RESUMEN

In both animal and plants, establishment of body axes is fundamental for proper organ development. Plant roots show two main developmental axes: the proximo-distal axis, which spans from the hypocotyl-root junction to the root tip; and the radial axis, which traverses from the vascular tissue to the epidermis. Root axes are determined in the root meristem. The root meristem occupies the tip of the root and contains self-renewing stem cells, which continuously produce new root cells. An intricate network of signalling pathways regulates meristem function and patterning to ensure proper root development and growth. In the last decade, miRNAs, 20-21 nucleotide-long molecules with morphogenetic activity, emerged as central regulators of root cell patterning. Their activity intersects with master regulators of meristematic activity, including phytohormones. In this review, we discuss the latest findings about the activity of miRNAs and their interaction with other molecular networks in the formation of root meristem axes. Furthermore, we describe how these small molecules allow root growth to adapt to changes in the environment, while maintaining the correct patterning.


Asunto(s)
Proteínas de Arabidopsis , Arabidopsis , MicroARNs , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas , Meristema/genética , Meristema/metabolismo , MicroARNs/genética , Reguladores del Crecimiento de las Plantas , Raíces de Plantas/genética , Raíces de Plantas/metabolismo
8.
Elife ; 102021 07 21.
Artículo en Inglés | MEDLINE | ID: mdl-34286693

RESUMEN

SOX2 expression levels are crucial for the balance between maintenance and differentiation of airway progenitor cells during development and regeneration. Here, we describe patterning of the mouse proximal airway epithelium by SOX21, which coincides with high levels of SOX2 during development. Airway progenitor cells in this SOX2+/SOX21+ zone show differentiation to basal cells, specifying cells for the extrapulmonary airways. Loss of SOX21 showed an increased differentiation of SOX2+ progenitor cells to basal and ciliated cells during mouse lung development. We propose a mechanism where SOX21 inhibits differentiation of airway progenitors by antagonizing SOX2-induced expression of specific genes involved in airway differentiation. Additionally, in the adult tracheal epithelium, SOX21 inhibits basal to ciliated cell differentiation. This suppressing function of SOX21 on differentiation contrasts SOX2, which mainly drives differentiation of epithelial cells during development and regeneration after injury. Furthermore, using human fetal lung organoids and adult bronchial epithelial cells, we show that SOX2+/SOX21+ regionalization is conserved. Lastly, we show that the interplay between SOX2 and SOX21 is context and concentration dependent leading to regulation of differentiation of the airway epithelium.


Asunto(s)
Diferenciación Celular/genética , Diferenciación Celular/fisiología , Células Epiteliales/metabolismo , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Factores de Transcripción SOXB2/genética , Factores de Transcripción SOXB2/metabolismo , Animales , Humanos , Pulmón/crecimiento & desarrollo , Pulmón/metabolismo , Ratones , Células Madre/metabolismo , Tráquea/metabolismo , Transcriptoma
9.
Psicol. rev ; 30(1): 146-167, jun. 2021.
Artículo en Portugués | LILACS, Index Psicología - Revistas | ID: biblio-1395822

RESUMEN

Na contemporaneidade, acirram-se os efeitos estruturais do mal-estar da civilização discutidos por Freud. Nos deteremos naquele que advém da relação com o próximo. Quando a pulsão de morte reproduz uma forma de insatisfação reiterada, o tratamento desse excesso pode recair sobre o corpo do outro que guarda uma diferença de gozo. A maneira como o gozo íntimo ganha forma de estrangeiro habitando, como o pior, o próximo, configura uma suposição de suspeita que sustenta um modo de laço social. Lacan chega a falar que, na matriz de toda fraternidade, está a segregação. Formamos comunidades de gozo e excluímos toda a forma diferente de satisfação que nos ameace. Na atualidade, com o acúmulo do capital, aliado aos efeitos do avanço científico, algo se modificou no laço social e produziu, dessa matriz, uma nova gramática de inimigo, que denominamos sujeito suposto suspeito como um dos nomes do pior. Contra essa lógica, a emancipação e as saídas possíveis que a psicanálise aponta para uma vida em-comum, na solidão da responsabilidade do gozo de cada um, dizem respeito às soluções éticas que enfrentam, desde dentro, todo o idealismo superegóico.


In contemporary times, the structural effects discussed by Freud in the malaise of civilization are intensified. We will dwell on what comes from the relationship with the neighbor. When the death drive reproduces a form of repeated dissatisfaction, the treatment for this excess can fall on the body of the other who has a different satisfaction. The way intimate satisfaction takes shape as a foreigner inhabiting, like the worst, the neighbor, determines an assumption of suspicion that supports a mode of social bonding. Lacan even says that segregation is in the matrix of all fraternity. We create communities of satisfaction and exclude any different form of enjoyment that threatens us. Currently, the accumulation of capital mixed with the effects of scientific advancement brought changes to social bonding and produced, from this matrix, a new grammar for what's enemy. Suspected subject is a naming for the worse. Against this logic, the emancipation and the possible solutions that psychoanalysis suggests for a life in common, in the solitude and responsibility of each one's satisfaction, concerns the ethical solutions that face, from within, all the superegoic idealism.


En los tiempos contemporáneos, los efectos estructurales del malestar de la civilización discutidos por Freud se intensifican. Nos detendremos en el que proviene de la relación con los demás. Cuando el pulsion de la muerte reproduce una forma de insatisfacción repetida, el tratamiento de este exceso puede recaer en el cuerpo del otro, que tiene una diferencia de goce. El goce íntimo es proyectado como extranjero habitando en el prójimo, como si encarnara lo peor que proyectaba sobre él, configura una presunción de sospecha que sustenta un modo de vínculo social. Lacan llega al extremo de decir que la segregación está en el corazón de cada fraternidad. Formamos comunidades de goce y excluimos cualquier forma diferente de satisfacción que nos amenace. Hoy en día, con la acumulación de capital, combinada con los efectos del avance científico, algo ha cambiado en el vínculo social y ha producido, a partir de esta matriz, una nueva gramática del enemigo, que llamamos el sujeto supuesto sospechoso como uno de los nombres de lo peor. Contra esta lógica, la emancipación y las posibles soluciones que apunta el psicoanálisis en una vida común, en la soledad de la responsabilidad del goce de cada uno, conciernen a las soluciones éticas que enfrentan, desde adentro, todo idealismo superegoico.


Asunto(s)
Humanos , Masculino , Femenino , Odio , Psicoanálisis/ética , Sujetos de Investigación/psicología , Relaciones Interpersonales
10.
Genesis ; 57(9): e23309, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31162816

RESUMEN

The placement of eyes on insect head is an important evolutionary trait. The stalk-eyed fly, Cyrtodopsis whitei, exhibits a hypercephaly phenotype where compound eyes are located on lateral extension from the head while the antennal segments are placed inwardly on this stalk. This stalk-eyed phenotype is characteristic of the family Diopsidae in the Diptera order and dramatically deviates from other dipterans, such as Drosophila. Like other insects, the adult eye and antenna of stalk-eyed fly develop from a complex eye-antennal imaginal disc. We analyzed the markers involved in proximo-distal (PD) axis of the developing eye imaginal disc of the stalk-eyed flies. We used homothorax (hth) and distalless (dll), two highly conserved genes as the marker for proximal and distal fate, respectively. We found that lateral extensions between eye and antennal field of the stalk-eyed fly's eye-antennal imaginal disc exhibit robust Hth expression. Hth marks the head specific fate in the eye- and proximal fate in the antenna-disc. Thus, the proximal fate marker Hth expression evolves in the stalk-eyed flies to generate lateral extensions for the placement of the eye on the head. Moreover, during pupal eye metamorphosis, the lateral extension folds back on itself to place the antenna inside and the adult compound eye on the distal tip. Interestingly, the compound eye in other insects does not have a prominent PD axis as observed in the stalk-eyed fly.


Asunto(s)
Ojo Compuesto de los Artrópodos/embriología , Dípteros/embriología , Genes de Insecto , Marcadores Genéticos , Animales , Dípteros/genética , Drosophila/genética , Inducción Embrionaria , Proteínas de Homeodominio/genética , Metamorfosis Biológica/genética , Retina/embriología
11.
Rev. colomb. psicol ; 28(1): 81-98, ene.-jun. 2019. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1013946

RESUMEN

Resumen El aprendizaje de un sistema de conceptos científicos es la base del desarrollo de conceptos en la escuela. Uno de los obstáculos para lograrlo es que los conceptos se aprenden como palabras vacías sin contenido adecuado. Este estudio ilustra la forma en la que las ideas de Vygotsky se pueden usar para superar dicho obstáculo. Para describir el proceso de comprensión de los conceptos medio ambiente y naturaleza, se implementó una estrategia pedagógica en una muestra de 80 estudiantes de grado séptimo. Los resultados muestran que la estrategia fue efectiva para ayudar a los estudiantes a superar sus preconcepciones y construir conceptos adecuados, representados en modelos y textos expositivos.


Abstract Although learning a system of scientific concepts is the basis for the development of concepts in school, this objective is hindered by the fact that concepts are learned as empty words lacking adequate content. This study illustrates how Vygotsky's ideas can be used to overcome that obstacle. In order to describe the process of understanding the concepts of environment and nature, a pedagogic strategy was implemented in a sample of seventh-grade students. Results show that the strategy was effective in helping students go beyond their preconceptions and be able to build adequate concepts, represented in models and expository texts.


Resumo A aprendizagem de um sistema de conceitos científicos é a base do desenvolvimento de conceitos na escola. Um dos obstáculos para alcança-la é que os conceitos são aprendidos como palavras vazias sem conteúdo adequado. Este estudo ilustra a maneira em que as ideias de Vygotsky podem ser usadas para superar esse obstáculo. Para descrever o processo de compreensão dos conceitos meio ambiente e natureza, foi implementada uma estratégia pedagógica em uma amostra de 80 alunos do sétimo ano. Os resultados mostram que a estratégia foi eficaz em ajudá-los a superar seus preconceitos e construir conceitos adequados, representados em modelos e textos expositivos.

12.
Elife ; 72018 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-30095068

RESUMEN

Wingless/Wnts are signalling molecules, traditionally considered to pattern tissues as long-range morphogens. However, more recently the spread of Wingless was shown to be dispensable in diverse developmental contexts in Drosophila and vertebrates. Here we demonstrate that release and spread of Wingless is required to pattern the proximo-distal (P-D) axis of Drosophila Malpighian tubules. Wingless signalling, emanating from the midgut, directly activates odd skipped expression several cells distant in the proximal tubule. Replacing Wingless with a membrane-tethered version that is unable to diffuse from the Wingless producing cells results in aberrant patterning of the Malpighian tubule P-D axis and development of short, deformed ureters. This work directly demonstrates a patterning role for a released Wingless signal. As well as extending our understanding about the functional modes by which Wnts shape animal development, we anticipate this mechanism to be relevant to patterning epithelial tubes in other organs, such as the vertebrate kidney.


Asunto(s)
Tipificación del Cuerpo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/fisiología , Regulación del Desarrollo de la Expresión Génica , Túbulos Renales Distales/fisiología , Túbulos Renales Proximales/fisiología , Proteína Wnt1/metabolismo , Animales , Proteínas de Drosophila/genética , Drosophila melanogaster/embriología , Embrión no Mamífero/citología , Embrión no Mamífero/fisiología , Túbulos Renales Distales/embriología , Túbulos Renales Proximales/embriología , Morfogénesis , Vía de Señalización Wnt , Proteína Wnt1/genética
13.
Agora USB ; 18(1): 236-244, ene.-jun. 2018.
Artículo en Español | LILACS | ID: biblio-949814

RESUMEN

Resumen La implementación de rutas de formación para los docentes orientados a la cualificación, diseño y aplicación de recursos educativos digitales son necesarios y prioritarios para que las instituciones avancen hacia la transformación cultural requerida en los procesos de enseñanza-aprendizaje con soporte en las TIC. Esto implica una revisión de la construcción de los conceptos de comunidades de aprendizaje, práctica, práctica virtual, zona de desarrollo próximo en la práctica pedagógica, las relaciones en los ambientes virtuales de aprendizaje y las competencias docentes en el uso de las TIC.


Abstract The implementation of teacher training pathways aiming at the qualifica tion, design, and application of digital educational resources are necessary and priority so that institutions move towards the required cultural transformation in the teaching and learning processes with ICT support. This involves a review of the construction of the concept of communities of learning, communities of practice, virtual practice, zone of proximal development in pedagogical practice, relationships in virtual learning environments, and educational expertise in the use of ICT.

14.
Ciênc. agrotec., (Impr.) ; 42(1): 80-92, Jan.-Feb. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-890664

RESUMEN

ABSTRACT Portable X-ray fluorescence spectrometer (pXRF) has been recently adopted by the Soil Science community for uses in both field and laboratory, obtaining the total content of several chemical elements in a few seconds. Sulfuric acid digestion is an expensive and time-consuming laboratory analysis that provides contents of Fe2O3, Al2O3, SiO2, TiO2 and P2O5, important for soil studies. Due to few pXRF studies in tropical soils, this work aimed to compare contents of Fe2O3, Al2O3, SiO2, TiO2 and P2O5 obtained by pXRF with sulfuric acid digestion results, and to evaluate the effects of varying forms of preparing soil samples and scanning with pXRF on the resulting values in Brazilian soils. Soils were scanned in five conditions in-field (in situ) and in laboratory, evaluating varying sample preparation methods, particle sizes and soil moisture. Four pXRF scanning operational modes were tested. Linear regressions were adjusted between results of pXRF and sulfuric acid digestion. Equations were validated with an independent set of samples. Statistical analyses compared the methods of preparing the samples. Adequate linear models reached R2 of 0.99 and 0.89 for Fe2O3 and TiO2, respectively. Validation promoted R2 greater than 0.97 and RMSE and ME close to zero for both oxides. Statistical differences of pXRF results were found among the methods of preparing samples. pXRF spectrometer has great potential to obtain Fe2O3 and TiO2 content rapidly and economically with high correspondence with laboratory results of sulfuric acid digestion analysis. Varying methods of preparing the samples promote differences in the results of pXRF.


RESUMO O espectrômetro portátil de fluorescência de raios-X (pXRF) foi recentemente adotado pela Ciência do Solo, para uso em campo e laboratório, para obtenção do conteúdo total de vários elementos químicos em poucos segundos. A digestão com ácido sulfúrico é uma análise laboratorial cara e demorada que fornece teores de Fe2O3, Al2O3, SiO2, TiO2 e P2O5, importantes para estudos sobre solos. Devido aos poucos estudos sobre o pXRF em solos tropicais, este trabalho objetivou comparar os teores de Fe2O3, Al2O3, SiO2, TiO2 e P2O5 obtidos pelo pXRF com os resultados de digestão com ácido sulfúrico e avaliar os efeitos de diferentes formas de preparo de amostras de solo e leitura com o pXRF sobre seus resultados para solos brasileiros. Os solos foram submetidos a leituras com o pXRF em cinco condições, em campo (in situ) e em laboratório, avaliando variados métodos de preparo de amostras, tamanhos de partículas e umidade do solo. Quatro modos de operação do pXRF foram testados. Regressões lineares foram ajustadas entre os resultados do pXRF e digestão com ácido sulfúrico. As equações foram validadas com um conjunto independente de amostras. Análises estatísticas compararam os métodos de leitura de amostras. Modelos lineares adequados atingiram R2 de 0,99 e 0,89 para Fe2O3 e TiO2, respectivamente. A validação promoveu R2 maior que 0.97 e RMSE e ME próximos a zero para ambos os óxidos. Foram encontradas diferenças estatísticas dos resultados do pXRF entre os métodos de preparo de amostras. O pXRF possui um grande potencial para obter rápida e economicamente os teores de Fe2O3 e TiO2 com elevada correspondência com os resultados laboratoriais da análise da digestão com ácido sulfúrico. Métodos variáveis ​​de preparo das amostras promovem diferenças nos resultados de pXRF.

15.
São Paulo; s.n; s.n; 2018. 206 p. graf, tab.
Tesis en Portugués | LILACS | ID: biblio-970094

RESUMEN

O uso de ferramentas estatísticas no ciclo de vida de um produto farmacêutico permite verificar e controlar o processo tendo como objetivo a sua melhoria contínua. No presente estudo foi avaliada a estabilidade e a capacidade estatística do processo de fabricação dos comprimidos revestidos de lamivudina 3TC e zidovudina AZT (150 + 300 mg) fabricados pela Fundação para o Remédio Popular "Chopin Tavares de Lima" (FURP). Esse medicamento, distribuido gratuitamente pelo programa DST/AIDS do Ministério da Saúde, e fabricado por compressão direta, processo rápido que permite a implementação futura da tecnologia analítica de processo (Process Analytical Technology - PAT). No Capítulo I foi realizada avaliação retrospectiva da variabilidade de atributos criticos da qualidade de 529 lotes dos comprimidos fabricados de acordo com a RDC ANVISA 17/2010 e as monografias oficiais, sendo tais atributos: peso médio, uniformidade de dose unitária e % m/v de fármaco dissolvido, antes e após o revestimento. O objetivo foi identificar eventuais causas especiais de variabilidade dos processos que permitam melhorias contínuas. No Capitulo II foi desenvolvida metodologia analítica empregando a espectroscopia no infravermelho próximo com transformada de Fourier para a avaliação da homogeneidade da mistura dos pós. Nesse estudo foram analisadas amostras de misturas dos fármacos lamivudina 3TC e zidovudina AZT e mistura excipiente, empregando como método de referência a CLAE, para a quantificação desses dois fármacos. No Capitulo I, a avaliação do processo para o peso médio revelou a necessidade de investigação das causa especiais de variabilidade, evidenciada por meio das cartas de controle. Os resultados do ano de 2015 indicaram necessidade de centralização e de consistência do processo, com redução de probabilidade de falha. As cartas de controle para uniformidade de dose unitária, no ano de 2013, revelaram menor variabilidade do processo. Porem, nesse ano, a análise estatística para a dissolução revelou processo descentralizado e sem consistência, com maior evidência para o fármaco 3TC que demonstrou menor desempenho, Cpk<1,0. A avaliação da estabilidade e da capacidade do processo de fabricação de comprimidos de lamivudina + zidovudina (150+300 mg), no período de 2012 a 2015, permitiu o maior entendimento de suas fontes de variação. Foi possível detectar e determinar o grau dessa variação e seu impacto no processo e nos atributos críticos de qualidade do produto com evidentes oportunidades de melhoria do processo, reduzindo os riscos para o paciente. No capítulo II, no desenvolvimento do método, as estatísticas de validação revelaram que os menores valores de BIAS foram observados para a 3TC, 0,000116 e 0,0021, respectivamente para validação cruzada e validação. Os valores de BIAS próximos a zero indicaram reduzida porcentagem de variabilidade do método. O presente estudo demonstrou a viabilidade do uso do modelo desenvolvido para a quantificação da 3TC e AZT por FT-NIR apos ajustes que contribuam para a elevação de R, R2 e RPD para valores aceitáveis. Valores de RPD acima de 5,0 que permitem o uso do modelo para uso em controle de qualidade


The use of statistical tools in the life cycle of a pharmaceutical product allows verifying and controlling the process aiming at its continuous improvement. In the present study, the stability and statistical capacity of the lamivudine coated tablets 3TC and zidovudine AZT (150 + 300 mg) manufactured by the Chopin Tavares de Lima Foundation (FURP) were evaluated. This drug, distributed free of charge by the Ministry of Health's DST/AIDS program, is manufactured by direct compression, a rapid process that allows the future implementation of Process Analytical Technology (PAT). In Chapter I, a retrospective evaluation of the variability of critical quality attributes of 529 batches of tablets manufactured was carried out, such attributes being: mean weight, unit dose uniformity and % m/v of dissolved drug substances, before and after coating. The objective was to identify possible special causes of variability of the processes that allow continuous improvements. In Chapter II an analytical methodology was developed employing the near infrared spectroscopy with Fourier transform for the evaluation of the homogeneity of the powder mixture. In this study, samples of mixtures of the drugs lamivudine 3TC and zidovudine AZT and excipient mixture were analyzed, using as reference method the HPLC, for the quantification of these two drugs. In Chapter I, the evaluation of the process for the mean weight revealed the need to investigate the special cause of variability, as evidenced by the charts. The results of the year 2015 indicated the need for centralization and process consistency, with a reduction in the probability of failure. The control charts for unit dose uniformity, in the year 2013, revealed less process variability. However, in that year, the statistical analysis for dissolution revealed a decentralized process with no consistency, with greater evidence for the 3TC drug that showed lower performance, Cpk<1.0. The evaluation of the stability and capacity of the lamivudine + zidovudine tablet manufacturing process (150 + 300 mg) in the period from 2012 to 2015 allowed a better understanding of its sources of variation. It was possible to detect and determine the degree of this variation and its impact on the process and the critical quality attributes of the product with evident opportunities to improve the process, reducing risks for the patient. In Chapter II, in the development of the method, the validation revealed that the lowest values of BIAS were observed for 3TC, 0.000116 and 0.0021, respectively for cross validation and validation. BIAS values close to zero indicated a reduced percentage of variability of the method. The present study demonstrated the feasibility of using the model developed for the quantification of 3TC and AZT by FT-NIR after adjustments that contribute to the elevation of R, R2 and RPD to acceptable values. RPD values above 5.0 that allow the use of the model for use in quality control


Asunto(s)
Comprimidos/análisis , Zidovudina/análisis , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Lamivudine/análisis , Estudio de Validación , Composición de Medicamentos/instrumentación
16.
Ciênc. agrotec., (Impr.) ; 41(6): 648-664, Nov.-Dec. 2017. tab, graf
Artículo en Inglés | LILACS | ID: biblio-890655

RESUMEN

ABSTRACT Determination of soil properties ​​helps in the correct management of soil fertility. The portable X-ray fluorescence spectrometer (pXRF) has been recently adopted to determine total chemical element contents in soils, allowing soil property inferences. However, these studies are still scarce in Brazil and other countries. The objectives of this work were to predict soil properties using pXRF data, comparing stepwise multiple linear regression (SMLR) and random forest (RF) methods, as well as mapping and validating soil properties. 120 soil samples were collected at three depths and submitted to laboratory analyses. pXRF was used in the samples and total element contents were determined. From pXRF data, SMLR and RF were used to predict soil laboratory results, reflecting soil properties, and the models were validated. The best method was used to spatialize soil properties. Using SMLR, models had high values of R² (≥0.8), however the highest accuracy was obtained in RF modeling. Exchangeable Ca, Al, Mg, potential and effective cation exchange capacity, soil organic matter, pH, and base saturation had adequate adjustment and accurate predictions with RF. Eight out of the 10 soil properties predicted by RF using pXRF data had CaO as the most important variable helping predictions, followed by P2O5, Zn and Cr. Maps generated using RF from pXRF data had high accuracy for six soil properties, reaching R2 up to 0.83. pXRF in association with RF can be used to predict soil properties with high accuracy at low cost and time, besides providing variables aiding digital soil mapping.


RESUMO A determinação de atributos do solo auxilia no correto manejo da sua fertilidade. O equipamento portátil de fluorescência de raios-X (pXRF) foi recentemente adotado para determinar o teor total de elementos químicos em solos, permitindo inferências sobre atributos do solo. No entanto, esses estudos ainda são escassos no Brasil e em outros países. Os objetivos deste trabalho foram prever atributos do solo a partir de dados do pXRF, comparando-se os métodos de regressão linear múltipla stepwise (SMLR) e de random forest (RF), além de mapear e validar atributos do solo. 120 amostras de solo foram coletadas em três profundidades e submetidas a análises laboratoriais. Utilizou-se o pXRF para leitura das amostras e determinou-se o teor total de elementos. A partir dos dados do pXRF, foram utilizadas SMLR e RF para predizer resultados laboratoriais, que refletem atributos do solo, e os modelos foram validados. O melhor método foi utilizado para espacializar os atributos do solo. Utilizando SMLR, os modelos apresentaram valores elevados de R² (≥0,8), porém maior acurácia foi obtida na modelagem com RF. A capacidade de troca de cátions potencial e efetiva, matéria orgânica do solo, pH, saturação por bases e teores trocáveis de Ca, Al e Mg apresentaram ajustes adequados e predições acuradas com RF. Dos dez atributos do solo preditos por RF a partir de dados do pXRF, sete apresentavam CaO como a variável mais importante para auxiliar as predições, seguido por P2O5, Zn e Cr. Os mapas gerados a partir de dados do pXRF usando RF apresentaram adequados valores de R² para seis atributos do solo, atingindo R2 de até 0,83. O pXRF em associação com RF pode ser usado para prever atributos do solo com elevada acurácia, com rapidez e a baixo custo, além de proporcionar variáveis que auxiliam o mapeamento digital de solos.

17.
Rev. Assoc. Psicanal. Porto Alegre ; (51/52): 149-156, jul. 2016-jun. 2017.
Artículo en Portugués | Index Psicología - Revistas | ID: psi-71852

RESUMEN

O texto trata do amor ao próximo, mandamento da tradição judaico-cristã, partindo de citações bíblicas, do questionamento de Freud e da retomada feita por Lacan no seminário sobre a ética. Recuar de amar ao próximo pode ser uma forma de resistência ao gozo, resistência a uma crueldade intolerável, uma vez que o gozo de um, ao implicar o outro, pode significar o seu mal e vice-versa. O próximo pode, no entanto, ser tomado para além da referência ao amor narcísico, ao gozo e à maldade, como possibilidade de reparar uma falha na estrutura, tal como foi proposto por Vegh, o que contribui para a reflexão acerca do mal-estar nos tempos sombrios em que vivemos. (AU)


The text deals with the love of the neighbour, a commandment of the Judeo-Christian tradition, starting with biblical quotations, Freud’s questioning and the resumption made by Lacan in the seminar on ethics. To withdraw from loving one’s neighbour can be a form of resistance to jouissance, resistance to intolerable cruelty, since the jouissance of one, by implicating the other, can mean its evil and vice versa. The neighbour can, however, be taken beyond the reference to narcissistic love, to jouissance and evil, as a possibility to repair a lack in the structure, as proposed by Vegh, which contributes to the reflection on the discontents in the somber times in which we live. (AU)


Asunto(s)
Psicoanálisis
18.
Development ; 144(3): 479-486, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28087638

RESUMEN

An intrinsic timing mechanism specifies the positional values of the zeugopod (i.e. radius/ulna) and then autopod (i.e. wrist/digits) segments during limb development. Here, we have addressed whether this timing mechanism ensures that patterning events occur only once by grafting GFP-expressing autopod progenitor cells to the earlier host signalling environment of zeugopod progenitor cells. We show by detecting Hoxa13 expression that early and late autopod progenitors fated for the wrist and phalanges, respectively, both contribute to the entire host autopod, indicating that the autopod positional value is irreversibly determined. We provide evidence that Hoxa13 provides an autopod-specific positional value that correctly allocates cells into the autopod, most likely through the control of cell-surface properties as shown by cell-cell sorting analyses. However, we demonstrate that only the earlier autopod cells can adopt the host proliferation rate to permit normal morphogenesis. Therefore, our findings reveal that the ability of embryonic cells to differentially reset their intrinsic behaviours confers robustness to limb morphogenesis. We speculate that this plasticity could be maintained beyond embryogenesis in limbs with regenerative capacity.


Asunto(s)
Esbozos de los Miembros/citología , Esbozos de los Miembros/embriología , Animales , Animales Modificados Genéticamente , Proteínas Aviares/genética , Proteínas Aviares/metabolismo , Tipificación del Cuerpo , Puntos de Control del Ciclo Celular , Linaje de la Célula , Embrión de Pollo , Células Madre Embrionarias/citología , Células Madre Embrionarias/metabolismo , Células Madre Embrionarias/trasplante , Regulación del Desarrollo de la Expresión Génica , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Esbozos de los Miembros/metabolismo , Regeneración , Alas de Animales/citología , Alas de Animales/embriología , Alas de Animales/metabolismo
19.
Evolution ; 70(7): 1530-41, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27272402

RESUMEN

To predict the response of complex morphological structures to selection it is necessary to know how the covariation among its different parts is organized. Two key features of covariation are modularity and integration. The Drosophila wing is currently considered a fully integrated structure. Here, we study the patterns of integration of the Drosophila wing and test the hypothesis of the wing being divided into two modules along the proximo-distal axis, as suggested by developmental, biomechanical, and evolutionary evidence. To achieve these goals we perform a multilevel analysis of covariation combining the techniques of geometric morphometrics and quantitative genetics. Our results indicate that the Drosophila wing is indeed organized into two main modules, the wing base and the wing blade. The patterns of integration and modularity were highly concordant at the phenotypic, genetic, environmental, and developmental levels. Besides, we found that modularity at the developmental level was considerably higher than modularity at other levels, suggesting that in the Drosophila wing direct developmental interactions are major contributors to total phenotypic shape variation. We propose that the precise time at which covariance-generating developmental processes occur and/or the magnitude of variation that they produce favor proximo-distal, rather than anterior-posterior, modularity in the Drosophila wing.


Asunto(s)
Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/genética , Morfogénesis , Animales , Evolución Biológica , Femenino , Masculino , Alas de Animales/crecimiento & desarrollo
20.
Artículo en Inglés | MEDLINE | ID: mdl-27050119

RESUMEN

This report aims at describing two new clinical phenotypes associated with classical features of cervical flexion induced myelopathy (CFIM). The description is of a prospective case series of six young males presenting with progressive bilateral proximal/proximo-distal amyotrophy of upper limbs and demonstrating the typical MRI characteristics of Hirayama disease. All underwent detailed clinical, electrophysiologcal and imaging studies. The affected muscles were shoulder girdles and arms in proximal form (n = 2) and the entire upper limbs in proximo-distal form (n = 4). The mean age at onset was 21.0 ± 3.3 years, duration of illness was 6.7 ± 3.4 years, period of progression was 39.0 ± 27.3 months followed by a stable phase of 45.0 ± 50.0 months. All had severe wasting and weakness of affected muscles leading to significant disability. Nerve conduction studies revealed grossly reduced compound muscle action potential amplitudes with neurogenic pattern on electromyography of affected muscles. On MRI all revealed evidence of cervical cord atrophy with signal changes, dural detachment and extensive posterior epidural enhancement (variably from C1 to T2 level). Altered cervical curvature was prominent. In conclusion, hitherto unreported, we describe two additional clinical phenotypes (proximal and proximo-distal forms) of Hirayama disease demonstrating the cardinal imaging features of CFIM.


Asunto(s)
Vértebras Cervicales/patología , Enfermedades de la Médula Espinal/etiología , Atrofias Musculares Espinales de la Infancia/complicaciones , Extremidad Superior/fisiopatología , Adulto , Vértebras Cervicales/diagnóstico por imagen , Electromiografía , Potenciales Evocados Motores/fisiología , Humanos , Imagen por Resonancia Magnética , Masculino , Conducción Nerviosa , Estudios Retrospectivos , Enfermedades de la Médula Espinal/diagnóstico por imagen , Atrofias Musculares Espinales de la Infancia/diagnóstico por imagen
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