A characterization of quadric constant mean curvature hypersurfaces of spheres

Let $\phi:M\to\mathbb{S}^{n+1}\subset\mathbb{R}^{n+2}$ be an immersion of a complete $n$-dimensional oriented manifold. For any $v\in\mathbb{R}^{n+2}$, let us denote by $\ell_v:M\to\mathbb{R}$ the function given by $\ell_v(x)=\phi(x),v$ and by $f_v:M\to\mathbb{R}$, the function given by $f_v(x)=\nu(x),v$, where $\nu:M\to\mathbb{S}^{n}$ is a Gauss map. We will prove that if $M$ has constant mean curvature, and, for some $v\ne{\bf 0}$ and some real number $\lambda$, we have that $\ell_v=\lambda f_v$, then, $\phi(M)$ is either a totally umbilical sphere or a Clifford hypersurface. As an application, we will use this result to prove that the weak stability index of any compact constant mean curvature hypersurface $M^n$ in $\mathbb{S}^{n+1}$ which is neither totally umbilical nor a Clifford hypersurface and has constant scalar curvature is greater than or equal to $2n+4$.Comment: Final version (February 2008). To appear in the Journal of Geometric Analysi

Esbozo de una historiografía de la historia de la Iglesia en Venezuela (1965-2015)

La historiografía eclesiástica venezolana de estos últimos cincuenta años (1965-2015) se ha caracterizado por hacer un profundo análisis del decurso de las misiones que tuvo España en la amplia geografía venezolana. Los aportes de los investigadores en las relaciones de la Iglesia con los protagonistas de la independencia (1810-1821), con los caudillos del siglo xix y con la moderna república son los textos que nos presenta el autor en este artículo.The Venezuelan ecclesiastical historiography of the last fifty years (1965-2015) has focused on carrying out a profound inquiry into the consequences of Spain’s missions across the entire territory of Venezuela. This paper explains the results of this research concerning the relationships between the Church and the leaders of the independence movement (1810-1821), nineteenth-century political figures, and the modern Republic

Minimal cubic cones via Clifford algebras

We construct two infinite families of algebraic minimal cones in $R^{n}$. The first family consists of minimal cubics given explicitly in terms of the Clifford systems. We show that the classes of congruent minimal cubics are in one to one correspondence with those of geometrically equivalent Clifford systems. As a byproduct, we prove that for any $n\ge4$, $n\ne 16k+1$, there is at least one minimal cone in $R^{n}$ given by an irreducible homogeneous cubic polynomial. The second family consists of minimal cones in $R^{m^2}$, $m\ge2$, defined by an irreducible homogeneous polynomial of degree $m$. These examples provide particular answers to the questions on algebraic minimal cones posed by Wu-Yi Hsiang in the 1960's.Comment: Final version, corrects typos in Table

Avaliação do consumo de água no Sistema Intensivo de Suínos Criados ao Ar Livre - SISCAL.

bitstream/item/58372/1/CUsersPiazzonDocuments254.pd

Estrategias tecnológicas para el fomento de la conservación ambiental

El presente artículo tiene como objetivo identificar estrategias tecnológicas enfocadas al fomento de la conservación del medio ambiente, haciendo énfasis en la articulación de las TIC al desarrollo sostenible. A su vez se resalta su importancia como mediación para la interacción y entendimiento de las diferentes estrategias de conservación ambiental; así mismo, la emergencia de las ciudades inteligentes como alternativa de articulación de las TIC en diferentes contextos para el mejoramiento de la calidad de vida, encaminadas a disminuir la degradación ambiental y ampliar los impactos ambientales positivos.&nbsp

Soil quality impacts of current South American agricultural practices

Increasing global demand for oil seeds and cereals during the past 50 years has caused an expansion in the cultivated areas and resulted in major soil management and crop production changes throughout Bolivia, Paraguay, Uruguay, Argentina and southern Brazil. Unprecedented adoption of no-tillage as well as improved soil fertility and plant genetics have increased yields, but the use of purchased inputs, monocropping i.e., continuous soybean (Glycine max (L.) Merr.), and marginal land cultivation have also increased. These changes have significantly altered the global food and feed supply role of these countries, but they have also resulted in various levels of soil degradation through wind and water erosion, soil compaction, soil organic matter (SOM) depletion, and nutrient losses. Sustainability is dependent upon local interactions between soil, climate, landscape characteristics, and production systems. This review examines the region’s current soil and crop conditions and summarizes several research studies designed to reduce or prevent soil degradation. Although the region has both environmental and soil resources that can sustain current agricultural production levels, increasing population, greater urbanization, and more available income will continue to increase the pressure on South American croplands. A better understanding of regional soil differences and quantifying potential consequences of current production practices on various soil resources is needed to ensure that scientific, educational, and regulatory programs result in land management recommendations that support intensification of agriculture without additional soil degradation or other unintended environmental consequences.EEA ParanáFil: Wingeyer, Ana Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Paraná; ArgentinaFil: Amado, Telmo Jorge Carneiro. Universidade Federal de Santa Maria. Centro de Ciências Rurais; BrasilFil: Pérez Bidegain, Mario. Universidad de la República. Facultad de Agronomía; UruguayFil: Studdert, Guillermo. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Balcarce; ArgentinaFil: Perdomo Varela, Carlos Honorio. Universidad de la República. Facultad de Agronomía; UruguayFil: García, Fernando O. International Plant Nutrition Institute. Americas and Oceania Group. Latin America - Southern Cone; ArgentinaFil: Karlen, Douglas L. United States. Department of Agriculture. Agricultural Research Service; Estados Unido

Caracterização do sistema hidráulico e da qualidade da água em granjas de suínos da Região Sul do Brasil nas fases creche, crescimento e terminação.

bitstream/item/58382/1/CUsersPiazzonDocuments247.pdfAcesso em: 13 jun. 2007

Hybrid Deep Learning Gaussian Process for Diabetic Retinopathy Diagnosis and Uncertainty Quantification

Diabetic Retinopathy (DR) is one of the microvascular complications of Diabetes Mellitus, which remains as one of the leading causes of blindness worldwide. Computational models based on Convolutional Neural Networks represent the state of the art for the automatic detection of DR using eye fundus images. Most of the current work address this problem as a binary classification task. However, including the grade estimation and quantification of predictions uncertainty can potentially increase the robustness of the model. In this paper, a hybrid Deep Learning-Gaussian process method for DR diagnosis and uncertainty quantification is presented. This method combines the representational power of deep learning, with the ability to generalize from small datasets of Gaussian process models. The results show that uncertainty quantification in the predictions improves the interpretability of the method as a diagnostic support tool. The source code to replicate the experiments is publicly available at https://github.com/stoledoc/DLGP-DR-Diagnosis

Caracterización fisicoquímica y bacteriológica de queso blanco artesanal en la parroquia Buría, estado Lara, Venezuela

Artisan white cheeses represent a potential risk to cause foodborne illness, due to poor sanitary conditions processing; routinely using unpasteurized Milk makes these products become in vehicles for infectious pathogens. In order to evaluate the physical, chemical and bacteriological quality of fresh artisan cheeses, applying methodology established in Venezuelan COVENIN, 32 samples were analyzed from eight artisanal cheese making production units (UP) milk included in the Dairy Development Integrated Program (PIDEL) in Manzanita, Buría parish, Lara state. The data were statistically evaluated by ANOVA (P<0,05) and differences by Tukey test. Analysis of physicochemical characteristics (pH, humidity, acidity, chlorides, fat and protein) showed significant differences among the UP, attributable to manufacturing process. According to its consistency, cheeses are classified as firm/semi-hard and according to fat content in semi-fat (UP I, VIII) and fatty (UP II, III, IV, V, VI, VII). Also, significant variation (P<0.05) was checked in the bacteriological quality indicators: aerobic mesophilic (6.14±0.01 to 8.44±0.44 log UFC/g), total coliforms (4.30±0.00 to 7.09±0.85 log NMP/g), fecal coliforms (3.68±0.04 to 6.73±0.80 log NMP/g) and Escherichia coli (1.08±2.15 to 5.69±0.58 log NMP/g). Specific pathogens Staphylococcus aureus (0.00±0.00 to 6.99±0.82 log CFU/g) was identified and its evidenced absence of Salmonella sp. According to microbiological criteria, cheeses studied showed poor hygienic-sanitary quality; therefore, they are considered unfit for human consumption due to represent a latent risk of poisoning for the consumer.Los quesos blancos artesanales representan un riesgo potencial para originar enfermedades alimentarias, debido a las deficientes condiciones sanitarias durante su elaboración; habitualmente utilizando leche no pasteurizada que convierte estos subproductos en vehículos para patógenos infecciosos. Con el propósito de evaluar la calidad fisicoquímica y bacteriológica de quesos frescos artesanales, aplicando metodología establecida en las normas venezolanas COVENIN, fueron analizadas 32 muestras provenientes de ocho queseras artesanales de Unidades de Producción (UP) lecheras incluidas en el Programa Integral de Desarrollo Lechero (PIDEL) en Manzanita, parroquia Buría, estado Lara. Los datos se evaluaron estadísticamente mediante ANOVA (P<0,05) y las diferencias por prueba Tukey. El análisis de las características fisicoquímicas (pH, humedad, acidez, cloruros, grasa y proteína) arrojó diferencias significativas entre las UP, atribuibles al proceso de manufactura. Según su consistencia, los quesos se clasificaron como firmes/semiduros y de acuerdo al contenido de grasa, en semigrasos (UP I, VIII) y grasos (UP II, III, IV, V, VI, VII). Asimismo, se comprobó variación significativa (P<0,05) en los indicadores de calidad bacteriológica: recuento de aerobios mesófilos (6,14±0,01 a 8,44±0,44 log UFC/g), coliformes totales (4,30±0,00 a 7,09±0,85 log NMP/g), coliformes fecales (3,68±0,04 a 6,73±0,80 log NMP/g) y Escherichia coli (1,08±2,15 a 5,69±0,58 log NMP/g). Entre los patógenos específicos, se identificó Staphylococcus aureus (0,00±0,00 a 6,99±0,82 log UFC/g) y se evidenció ausencia de Salmonella sp. De acuerdo a criterios microbiológicos, los quesos estudiados mostraron deficiente calidad higiénico-sanitaria; por consiguiente se consideran no aptos para el consumo humano por representar un riesgo latente de intoxicación para el consumidor