Andrés Suárez-González, J.C. López-Ardao, Cándido López-Garcı́a, Manuel Fernández‐Veiga, Raúl F. Rodríguez‐Rubio, M.E. Sousa‐Vieira,
Several traffic measurement reports have convincingly shown the presence of self-similarity at the packet level in current networks, inducing as a result a revolution in the stochastic modeling of traffic. The essence of this behavior can be adequately captured by several classes of self-similar stochastic processes. But the use of these in performance analysis has opened new problems and research issues, also in simulation studies where the efficient generation of synthetic sample paths with self- ...
Tópico(s): Advanced Queuing Theory Analysis
2002 - Elsevier BV | Performance Evaluation
J.C. López-Ardao, Cándido López-Garcı́a, Andrés Suárez-González, Manuel Fernández‐Veiga, Raúl F. Rodríguez‐Rubio,
Several recent traffic measurement studies have convincingly shown the presence of self-similarity in modern high-speed networks, involving a very important revolution in the stochastic modeling of traffic. Thus the use of self-similar processes has opened new problems and research fields in network performance analysis, mainly in simulation studies, where the efficient synthetic generation of sample paths (traces) corresponding to self-similar traffic is one of the main topics. In this article, ...
Tópico(s): Transportation Planning and Optimization
2000 - Association for Computing Machinery | ACM Transactions on Modeling and Computer Simulation
Mónica Beatriz López-Hernández, Cándido López-Castañeda, J. Kohashi-Shibata, Salvador Miranda-Colín, Edwin Javier Barrios-Gómez, Carlos Gustavo Martínez Rueda,
El objetivo fue determinar la respuesta de genotipos de arroz (Oryza sativa) a la sequía. Se evaluó la tem- peratura del dosel vegetal (Tc) en emergencia de panícula (EP), oración (F) y en el llenado del grano (PLG), además del efecto de la Tc en el rendimiento de grano (RG) y sus componentes bajo riego (R) y sequía (S). El experimento se realizó en el Campo Experimental Zacatepec del Instituto Nacional de Investigaciones Forestales, Agrícolas y Pecuarias. Se evaluaron ocho líneas F6 del Fondo Latinoamericano ...
Tópico(s): Rice Cultivation and Yield Improvement
2018 - Universidad Juárez Autónoma de Tabasco | Ecosistemas y Recursos Agropecuarios
José Joskowicz, J.C. López-Ardao, Miguel A. González Ortega, Cándido López-Garcı́a,
In this paper, a simple mathematical formula is proposed which provides estimation for the perceived video quality, based solely in the codec used, the display format, the bit rate and the movement content in the original video. The quality metric used is one of the recently standardized in Recommendations ITU-T J.144 and ITU-R BT.1683, and developed by NTIA. The error obtained with the proposed formula, regarding to the ITU models, is between the ITU algorithms error margins, according to the subjective ...
Tópico(s): Advanced Vision and Imaging
2009 - Springer Science+Business Media | Lecture notes in computer science
Netzahualcóyotl Mayek-Pérez, Roberto García-Espinosa, Cándido López-Castañeda, Jorge Alberto Acosta Gallegos, June Simpson,
Alterations in water relations, growth and histopathology caused by Macrophomina phaseolina, causal agent of charcoal rot, and drought stress were characterized in Phaseolus vulgaris L. under controlled conditions.P. vulgaris cultivars BAT 477 and TLP 19 (resistant) and Pinto UI-114 and Rio Tibagi (susceptible) were cultivated under irrigation and drought stress conditions in infested or uninfested pots with a highly virulent isolate ofM. phaseolina . Drought stress showed higher negative effects than ...
Tópico(s): Agronomic Practices and Intercropping Systems
2002 - Elsevier BV | Physiological and Molecular Plant Pathology
Netzahualcóyotl Mayek Pérez, Cándido López Castañeda, Ernesto López Salinas, Javier Cumpián Gutiérrez, Ignacio Candelario Joaquín Torres, José Saúl Padilla Ramírez, Jorge Alberto Acosta Gallegos,
Resumen en: The reaction of common bean germplasm to charcoal rot under field conditions in Mexico was evaluated to determine the relationship between the susceptibi...
Tópico(s): Plant Pathogenic Bacteria Studies
2003 - | Revista mexicana de fitopatología(en línea)/Revista mexicana de fitopatología
Ivette Molina Serpa, Cándido López Pardo, Ricardo Hernández,
Se aplica un estudio ecológico para analizar la incidencia de tuberculosis en el municipio Marianao de la provincia Ciudad de La Habana de la República de Cuba en el período 1995-2000. Se realiza una caracterización de tal incidencia, se identifican patrones de distribución espacial y se determina la relación existente entre los niveles de incidencia de tuberculosis y factores del medio ambiente socioeconómico. La unidad espacial considerada son los 29 barrios del municipio Marianao. Entre otros ...
Tópico(s): Tuberculosis Research and Epidemiology
2003 - Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz | Cadernos de Saúde Pública
Cándido López-Castañeda, Richard A. Richards,
Barley yields more grain and total biomass than does triticale which in turn yields more biomass than do bread wheat, durum wheat and oats when sown at the same time in rainfed environments in southern Australia. To determine reasons for these differences, cultivars of each species were grown at five field sites and variation in their phenology and both pre- and post-anthesis growth was measured. Barley achieved a higher yield of grain and biomass in a shorter duration than the other species. It ...
Tópico(s): Pasture and Agricultural Systems
1994 - Elsevier BV | Field Crops Research
Cándido López-Castañeda, Richard A. Richards,
The relative performance of barley, bread wheat, durum wheat, triticale and oats was compared in rainfed environments to identify any outstanding features of these species that contribute to high grain yield. Fourteen high-yielding cultivars with a range of flowering times were evaluated in five rainfed environments. There was a terminal drought in all environments but water deficit was not a significant factor before flowering. Barley, which flowered earliest, had a 25% higher grain yield than ...
Tópico(s): Wheat and Barley Genetics and Pathology
1994 - Elsevier BV | Field Crops Research
Cándido López-Castañeda, R. A. Richards,
In rainfed environments in southern Australia the yield of both grain and biomass is greater in barley than it is for bread wheat, durum wheat, triticale and oats. Barley also has a faster leaf area development and biomass accumulation than the other species. To establish reasons for the greater biomass of barley in environments where soil water is limited, variation in the following were evaluated in field experiments: (i) water use or evapotranspiration (ET); (ii) water-use efficiency (WUE), i.e. ...
Tópico(s): Pasture and Agricultural Systems
1994 - Elsevier BV | Field Crops Research
G. J. Rebetzke, Cándido López-Castañeda, Tina Acuña, Anthony G. Condon, Richard A. Richards,
Selection for rapid leaf area growth has the potential to increase wheat biomass, and both water-use efficiency and weed competitiveness early in the season. Several morphological components contribute to increased seedling leaf area, including rapid seedling emergence and production of longer, wider leaves. Early emergence of a large coleoptile tiller has also been demonstrated to increase plant leaf area and biomass in wheat and other grass seedlings. Yet little is known of the extent and nature ...
Tópico(s): Genetics and Plant Breeding
2008 - CSIRO Publishing | Australian Journal of Agricultural Research
Sergio Herrerı́a-Alonso, Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
Network interfaces in most wired or wireless computing devices are greatly under-utilized, squandering energy while waiting for new packets to arrive. In this paper, we propose simple opportunistic algorithms to determine when to power down idle network interfaces in order to save much of that wasted energy. We also develop an analytic model to predict the amount of energy saved and the packet delay. The algorithms are compared to the best known opportunistic method, and it is shown that they provide ...
Tópico(s): Network Traffic and Congestion Control
2011 - Elsevier BV | Computer Networks
Sergio Herrerı́a-Alonso, Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
The last few years have seen a surge in the awareness of energy efficiency in many fields, including the networking community. As an answer towards such demands the IEEE has just released the 802.3az norm that provides a way for Ethernet physical interfaces to enter a low power mode when there is no traffic to send. At the same time there are starting to appear proposals for how to govern the physical interface state between active and low power modes. Among them, the burst transmission method stands ...
Tópico(s): Software-Defined Networks and 5G
2011 - IEEE Communications Society | IEEE Communications Letters
Sergio Herrerı́a-Alonso, Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
The IEEE 802.3az standard provides a mechanism to build energy efficient Ethernet interfaces via a low power idle mode that they can enter when there is no data to transmit. Several competing algorithms have appeared that make use of this mode to minimize energy consumption with little disruption to the traffic. Two algorithms stand out among those because of their simplicity and performance: frame transmission and burst transmission. Although these algorithms have been shown to be very efficient ...
Tópico(s): Advanced Optical Network Technologies
2012 - IEEE Communications Society | IEEE Transactions on Communications
Sergio Herrerı́a-Alonso, Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
The IEEE 802.3az standard provides a new low power mode that Ethernet network interfaces can use to save energy when there is no traffic to transmit. Simultaneously with the final standard approval, several algorithms were proposed to govern the physical interface state transition between the normal active mode and the new low power mode. In fact, the standard leaves this sleeping algorithm unspecified to spur competition among different vendors and achieve the greatest energy savings. In this paper, ...
Tópico(s): Network Time Synchronization Technologies
2012 - Elsevier BV | Computer Networks
Cándido López-Castañeda, Richard A. Richards, Graham D. Farquhar, R. E. Williamson,
Seedling characteristics between germination and the two leaf stage are principally responsible for variation in early leaf area development, or vigor, among temperate cereals. There is compelling evidence that this greater vigor confers substantial benefits in crops grown in dryland Mediterranean‐type environments. Experiments were conducted to determine the important factors that are likely to be responsible for variation in early vigor among barley ( Hordeum vulgare L.), bread wheat ( Triticum aestivum ...
Tópico(s): Genetics and Plant Breeding
1996 - Wiley | Crop Science
Yuri Villegas Aparicio, Alfonso Hernández Garay, Jorge Eduardo Pérez Pérez, Cándido López Castañeda, José Guadalupe Herrera Haro, Javier Francisco Enríquez Quiroz, Armando Gómez Vázquez,
The aim of this research was to determine the optimum harvesting time of alfalfa during the different seasons of the year. The experiment was carried out from April 2000 to March 2001, at the Instituto Tecnologico Agropecuario research unit, in Nazareno, Xoxocotlan, Oaxaca. The varieties used were: Valenciana and Oaxaca. Thirty-two plots (2 x 2 m) per variety were allocated in a completely randomized design with eight treatments and four replicates, treatments consisted of successive cuts at weekly ...
Tópico(s): Agroforestry and silvopastoral systems
2004 - National Institute of Research for Forestry, Agricultural and Livestock | Revista Mexicana de Ciencias Pecuarias
Sergio Herrerı́a-Alonso, Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
Current networking equipment usually provides several energy profiles with different performance capabilities. For example, in EPON systems, ONUs are able to switch their transmitters off when there is no data to transmit. This low power mode, known as doze mode, can significantly reduce power consumption in EPONs if wisely used. In this paper, we evaluate through simulation the potential power savings that can be obtained using this mode in many different scenarios. In particular, we analyze the ...
Tópico(s): Advanced Optical Network Technologies
2014 - Institute of Electrical and Electronics Engineers | Journal of Lightwave Technology
Netzahualcóyotl Mayek-Pérez, Cándido López-Castañeda, Mario Martín González-Chavira, Roberto García-Espinosa, Jorge Alberto Acosta Gallegos, Octavio Martínez, June Simpson,
Macrophomina phaseolina infects a wide range of plant species. In the case of Phaseolus vulgaris(the common bean), the fungus causes charcoal rot which can lead to severe losses especially under arid conditions. In order to combat the disease, it is necessary to have information on the population structure of the pathogen in terms of pathogenesis on different species which may be grown simultaneously or successively within a region. Previous reports have demonstrated the heterogeneity of the pathogen ...
Tópico(s): Plant Pathogens and Fungal Diseases
2001 - Elsevier BV | Physiological and Molecular Plant Pathology
Sergio Herrerı́a-Alonso, Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
The discontinuous reception (DRX) mechanism is commonly employed in current LTE networks to improve energy efficiency of user equipment (UE). DRX allows UEs to monitor the physical downlink control channel (PDCCH) discontinuously when there is no downlink traffic for them, thus reducing their energy consumption. However, DRX power savings are achieved at the expense of some increase in packet delay since downlink traffic transmission must be deferred until the UEs resume listening to the PDCCH. In ...
Tópico(s): Advanced Wireless Network Optimization
2015 - Institute of Electrical and Electronics Engineers | IEEE Journal on Selected Areas in Communications
Sergio Herrerı́a-Alonso, Andrés Suárez-González, Miguel Rodríguez‐Pérez, Raúl F. Rodríguez‐Rubio, Cándido López-Garcı́a,
Sunlight is one of the most frequently used ambient energy sources for energy harvesting in wireless sensor networks. Although virtually unlimited, solar radiation experiences significant variations depending on the weather, the season, and the time of day, so solar-powered nodes commonly employ solar prediction models to effectively adapt their energy demands to harvesting dynamics. We present in this paper a novel energy prediction model that makes use of the altitude angle of the sun at different ...
Tópico(s): UAV Applications and Optimization
2020 - Multidisciplinary Digital Publishing Institute | Sensors
M.E. Sousa‐Vieira, J.C. López-Ardao, Manuel Fernández‐Veiga, Miguel Rodríguez‐Pérez, Cándido López-Garcı́a,
Abstract The widespread use of computing and communications technologies has enabled the popularity of social networks oriented to learn. In this work, we study the nature and strength of associations between students using an online social network embedded in a learning management system. With datasets from three offerings of the same course, we mined the sequences of questions and answers posted by the students to identify structural properties of the social graph, patterns of collaboration among ...
Tópico(s): Online and Blended Learning
2017 - Wiley | Computer Applications in Engineering Education
Miguel Rodríguez‐Pérez, Manuel Fernández‐Veiga, Sergio Herrerı́a-Alonso, Mariem Hmila, Cándido López-Garcı́a,
The energy demands of Ethernet links have been an active focus of research in the recent years. This work has enabled a new generation of energy-efficient Ethernet (EEE) interfaces able to adapt their power consumption to the actual traffic demands, thus yielding significant energy savings. With the energy consumption of single network connections being a solved problem, in this paper, we focus on the energy demands of link aggregates that are commonly used to increase the capacity of a network connection. ...
Tópico(s): Network Traffic and Congestion Control
2015 - Institute of Electrical and Electronics Engineers | IEEE Systems Journal
Miguel Rodríguez‐Pérez, Sergio Herrerı́a-Alonso, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
In this paper, we research the feasibility of adapting the packet coalescing algorithm, used successfully in IEEE 802.3az Ethernet cards, to upstream EPON channels. Our simulation experiments show that, using this algorithm, great power savings are feasible without requiring any changes to the deployed access network infrastructure nor to protocols.
Tópico(s): Optical Network Technologies
2012 - IEEE Communications Society | IEEE Transactions on Communications
Sergio Herrera-Alonso, Miguel Rodríguez‐Pérez, Andrés Suárez-González, Manuel Fernández‐Veiga, Cándido López-Garcı́a,
TCP Vegas provides better performance compared to traditional TCP Reno schemes. However, backward traffic significantly degrades Vegas efficiency causing underutilization of the available bandwidth and unfairness. In this letter, we present an enhanced congestion control mechanism for TCP Vegas able to correctly remove the undesired impact of reverse traffic on bandwidth sharing. Furthermore, our proposal is easily deployable because it does not require neither clock synchronization nor any special ...
Tópico(s): Advanced Optical Network Technologies
2007 - IEEE Communications Society | IEEE Communications Letters
Cándido Hernández-López, Magı́ Farré, Pere N. Roset, E. Menoyo, Nieves Pizarro, Jordi Ortuño, Marta Torrens, Jordi Camı́, Rafael de la Torre,
3,4-Methylenedioxymethamphetamine (MDMA) is frequently consumed in association with alcohol. The effect of this combination in humans has not been previously investigated. Nine male healthy volunteers received single oral doses of 100 mg of MDMA plus 0.8 g/kg ethanol, 100 mg of MDMA, 0.8 g/kg of ethanol, and placebo in a double blind, double dummy, randomized crossover trial. Measurements included psychomotor performance, subjective effects, and pharmacokinetics. Plasma concentrations of MDMA showed ...
Tópico(s): Cannabis and Cannabinoid Research
2002 - American Society for Pharmacology and Experimental Therapeutics | Journal of Pharmacology and Experimental Therapeutics
Kamran Nayeri, Cándido M López-Pardo,
This article explores the effects on access to health care in Cuba of the severe economic crisis that followed the collapse of the Soviet Union and the monetary and market reforms adopted to confront it. Economic crises undermine health and well-being. Widespread scarcities and self-seeking attitudes fostered by monetary and market relations could result in differential access to health services and resources, but the authors found no evidence of such differential access in Cuba. While Cubans generally ...
Tópico(s): Caribbean history, culture, and politics
2005 - SAGE Publishing | International Journal of Health Services
Rafael de la Torre, Magı́ Farré, P. N. Roset, Cándido Hernández López, Manuel Mas, Jordi Ortuño, E. Menoyo, Nieves Pizarro, Jordi Segura, Jordi Camı́,
Abstract MDMA given at recreational doses (range tested 50 to 150 mg) to healthy volunteers, produced mydriasis and marked increases in systolic and diastolic blood pressure, heart rate, and pupillary diameter. MDMA induced changes on oral temperature. The time course of this observation was biphasic, as a slight decrease at 1 h and a slight increase at 2 and 4 h were observed. MDMA induced a slight dose‐dependent impairment on psychomotor performance. MDMA produced a marked rise in plasma cortisol ...
Tópico(s): Cannabis and Cannabinoid Research
2000 - Wiley | Annals of the New York Academy of Sciences
Blanca Sampedro, Cándido Hernández-López, José Ramón Ferrandiz, Aitziber Illaro, Emilio Fábrega, Antonio Cuadrado, Paula Iruzubieta, Susana Menéndez Álvarez-Dardet, Joaquín Cabezas, Javier Crespo,
Computerized physician order entry (CPOE) applications are widely used to prevent medical errors. In our center, a CPOE system has been in use since 2009 on both the inpatient and outpatient levels. A new and simple alert was introduced in the CPOE system to notify healthcare providers of the potential risk of viral reactivation when prescribing biological therapies, thereby facilitating the request for a serological profile (hepatitis B surface antigen [HBsAg], anti-HBc, and anti-HBs) in patients ...
Tópico(s): Liver Disease Diagnosis and Treatment
2014 - Lippincott Williams & Wilkins | Hepatology
Roberta Pacifici, P. Zuccaro, Cándido Hernández López, Simona Pichini, Simonetta Di Carlo, Magı́ Farré, P. N. Roset, Jordi Ortuño, Jordi Segura, Rafael de la Torre,
Cell-mediated immune response and release of cytokines after the administration of 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") alone and in combination with ethanol were assessed in a double blind, randomized, crossover, controlled clinical trial. Six healthy male recreational users of MDMA participated in four different experimental sessions, with a washout interval between sessions of 1 week, in which single oral doses of MDMA (100 mg), ethanol (0.8 g/kg), the combination of both drugs, and ...
Tópico(s): Tryptophan and brain disorders
2001 - American Society for Pharmacology and Experimental Therapeutics | Journal of Pharmacology and Experimental Therapeutics