374 research outputs found
Diseño e implementación de un modulador y demodulador OOK para comunicación por luz visible (VLC) utilizando la tarjeta FPGA CYCLONE III de ALTERA.
La finalidad del presente trabajo es transmitir datos a través de luz visible por medio de un diodo emisor de luz blanca (Light Emitting Diode, LED), de baja potencia, empleando modulación por encendido y apagado (On - Off Keying, OOK) punto a punto, utilizando la tarjeta para arreglos de compuertas programables en campo (Field Programmable Gate Array, FPGA) Cyclone III de Altera; además, realizar la respectiva simulación en el software Matlab (Simulink). Se realizó el estado del arte de la comunicación por luz visible (Visible Light Communication, VLC), lo cual contribuyó en el desarrollo tanto del diseño como la implementación del proyecto.
Finalmente, en los resultados experimentales obtenidos se analizó el desempeño de la comunicación óptica inalámbrica, tomando en cuenta parámetros como: tasa de bits, potencia, señal a ruido y tasa de bits erróneos (Bit Error Rate, BER), a través de curvas, con las cuales se puede comparar ventajas y limitaciones del tipo de modulación utilizada.The purpose of this work is to transmit data via visible light through a white light emitting diode (LED) and low power, using On - Off Keying (OOK) point to point, using the Altera Cyclone III FPGA board, also perform the respective simulation in Matlab software (Simulink). It was performed the state of the art of Visible Light Communication (VLC), which helped in the development of both the design and the implementation of the project.
Finally, experimental results obtained are analyzed the performance of wireless optical communication, taking into account parameters such as bit rate, power, signal to noise ratio and Bit Error Rate (BER), through curves, with which you can compare advantages and limitations on the type of modulation used
Implementación de la metodología 5 s para incrementar la productividad en el área de despacho a granel de una empresa de lubricantes del Perú año 2022.
La investigación se desarrolló en un contexto económico, empresarial signado por
un conjunto de características que hacen de NEXOS, una organización en cuya
estructura y funcionamiento deben introducirse cambios importantes para hacer
que, en ella se alcance niveles de productividad eficiente en los ejercicios
económicos anuales. Sobre todo, en el área de venta de lubricantes bajo la
modalidad de granel. Se planteó como objetivo general determinar el nivel de
productividad en el área de despacho a granel como consecuencia de la
implementación de la metodología 5 S. En tanto los problemas específicos se
vincularon con el incremento de la eficiencia y eficacia en el área de despacho a
granel de la empresa en referencia.
La población estuvo conformada por la producción de Bines de 1000 lts en el área
de gráneles. La muestra estuvo constituida por la producción de bines de 1000 lts
en el área referida. El muestreo fue no aleatorio, a juicio del investigador. Se
empleó enfoque cuantitativo, la información se recogió en el trabajo de campo,
luego medida, procesada e interpretada mediante la estadística descriptiva e
inferencial. El diseño fue cuasi experimental por lo que la productividad fue medida
antes (pre) y después (post) de la implementación de la metodología 5S en un
plazo de 90 días anteriores y 90 posteriores de la ejecución de la metodología
mencionada. Se demostró que en el área de estudio, el incremento de
productividad fue mayor en el post test, elevándose entre 18 a 20% de uno a otro
periodo
Geological setting and genesis of stratabound barite deposits at Múzquiz, Coahuila in northeastern Mexico
Peer ReviewedPreprin
ECOLOGY OF POLYLEPIS SPP FORESTS, AND PROPOSAL FOR ITS CONSERVATION IN THE ANDEAN REGION OF TACNA, PERU
The forests of Polylepis (queñoales) is one of the most important Andean forest ecosystems and with the greatest impact due to human activities. The objectives of the study were to determine the distribution and diversity of queñoa forests in the Andean region of Tacna, Peru. With this information, We propose the restoration and conservation plan for the Polylepis spp. For this purpose plots of 500 m2 were established. The sampling was simple random, taking a population census in each of the sample units in the 4 provinces (Jorge Basadre, Tacna, Tarata and Candarave). The total evaluation area was 27,491 hectares. The presence of two Polylepis species was identified. Polylepis rugulosa Bitter was registered in 9 districts with an altitudinal range of 3050 to 4226 m.a.s.l. in 6 life zones. Polylepis tarapacana Phil is distributed in the provinces of Tarata and Tacna within 3 districts. P. tarapacana occurs in an altitudinal range between 4230 and 4750 m.a.s.l. in 5 life zones. The tall and diameter of tree were variable for two species. The human impact for P. rugulosa was recorded: Not Intervented (76%), Semi Intervening (21%) and Intervened (3%). For P. tarapacana it was: Not Intervented (77%), Semi Interventions (21%) and Intervened (2%). According to the data gathered, the conservation plan is proposed, consisting of 5 guidelines: 1) education, 2) communication and capacity building, 3) conservation and sustainable management, 4) policies and regulations, and 5) research and monitoring
La clase Pino-Juniperetea en la provincia de León
Se ha realizado un estudio fitosociológico tanto de los sabinares montanos, como de los enebrales rastreros subalpinos y oromediterraneos, en la provincia de León, describiéndose cuatro nuevas subasociaciones: Juniperetum sabino-thuriferae quercetosum fagineae, Genisto sanabrensis-Juniperetum nanae echinospartetosum iberici y vaccinietosum uliginosi y Vaccinio myrtilli-Juniperetum nanae jasionetosum brevisepalae.In this paper a phytosociological study about montanous savin forets and, subalpine and oromediterranean creeping juniper shrubs in Leon province (NW Spain) is made.Four new subassociations are described: Juniperetum sahino-thunferae quercetosum fagineae, Gen isto sanabrensis-Juniperetum nanae echinospartetosum iberici and vaccinietosum uliginosi and Vaccinio myrtilli-Juniperetum nanae jasionetosumbrevisepalae
Self-report prevalence and associated factors to drug hypersensitivity in Mexican young adults
Background: Drug hypersensitivity is defined as any unfavorable reaction that occurs after the administration of any drug. It may
or may not be mediated by the involvement of the immune system. Epidemiological data related to drug hypersensitivity reactions
in our country are scarce.
Objective: To determine the prevalence of drug hypersensitivity in a group of young adults, as well as to identify associated
factors.
Methods: A structured questionnaire was applied to young people aged 18 to 25 years. The instrument was oriented to identify
reactions of drug hypersensitivity, as well as the most prevalent drugs involved. In addition, a personal and family history of atopic
diseases was included. Analysis for associations between variables was been done through logistic regression.
Results: The prevalence of drug hypersensitivity reactions was 12% (144 of 1,200). The antibiotics were the agents most related
to hypersensitivity reactions (9.8%) followed by nonsteroidal anti-inflammatory drugs (1.6%). Factors associated with drug
hypersensitivity were a personal history of asthma, odds ratio (OR) 3.15 (95% confidence interval [CI], 1.44–6.91), maternal and
paternal history of drug hypersensitivity, OR 2.33 (95% CI, 1.21–4.48) and OR 3.11 (95% CI, 1.22–7.92), respectively.
Conclusion: The results of this research show that drug hypersensitivity in young adults is a highly prevalent event and it is
associated with personal history of asthma and history of drug hypersensitivity in parents
Bacterias promotoras de crecimiento de plantas autóctonas y su efecto en "Prosopis chilensis" (Molina) Stunz
Today in Mexico are being deforestated the species Prosopis spp. for use as firewood and charcoal, in various arid regions of the country. For its production a synthetic fertilizer is used, thus there is an increase in soil, groundwater and aquifers salinity. This research was conducted in Santa Ana, Sonora, Mexico in 2006. Were isolated and purified microorganisms associated with the root system of Prosopis glandulosa growing in craters of the volcanic area from El Pinacate and Gran Desierto de Altar, Sonora Biosphere Reserve. The plant growth-promoting bacteria present the peculiarity of fixing atmospheric nitrogen; the effect of the isolates on germination and seedling development in P. chilensiswas measured. 19 colonies were isolated; of them, only one bacterial colony showed high acetylene reduction activity and ability to solubilize phosphate, was identified as Bacillus amyloliquefaciens. Our results suggest that B. amyloliquefaciens, has a particular affinity to grow from 0 to 0.75M of NaCl and develops at temperatures of 30 to 50 °C. The effects of inoculation of B. amyloliquefaciens, along with A. halopraeferens, showed favorable results in the increase of germination and seedling development of P. chilensis. This is the first report of B. amyloliquefaciensas a plant growth promoting bacteria associated with P. glandulosa.En la actualidad se está deforestando en México la especie de Prosopis spp. para utilizarse como leña y carbón, en diferentes zonas áridas de nuestro país. Para su producción se utiliza fertilizante sintético, con ello hay un incremento de salinidad del suelo, subsuelo y mantos acuíferos. La presente investigación se realizó en Santa Ana, Sonora, México en 2006. Se aislaron y purificaron microorganismos asociados al sistema radicular de Prosopis glandulosa que se desarrolla en cráteres de la zona volcánica de la reserva de la biosfera El Pinacate y Gran Desierto de Altar Sonora. Las bacterias promotoras de crecimiento de plantas presentan la peculiaridad de fijar el nitrógeno atmosférico; se midió el efecto de las cepas aisladas en germinación y en el desarrollo en plántulas de P. chilensis. Fueron aisladas 19 colonias; de ellas, solamente una colonia bacteriana mostró alta actividad de reducción de acetileno y capacidad de solubilizar fosfatos, se identificó como Bacillus amyloliquefaciens. Nuestros resultados sugieren que B. amyloliquefaciens, presenta una afinidad particular para crecer de 0 a 0.75 M de NaCl y desarrollarse en temperaturas de 30 a 50 °C. Los efectos de la inoculación de B. amyloliquefaciens, conjuntamente con A. halopraeferens, mostraron reultados favorables en el incremento de la germinación y el desarrollo de plántulas de P. chilensis. Éste es el primer reporte de B. amyloliquefaciens como bacteria promora de crecimiento de plantas asociada a P. glandulosa
Survival effects of antibiotic exposure during the larval and adult stages in the West Nile virus vector Culex pipiens
The ability of mosquitoes to transmit a pathogen is affected, among other factors, by their survival rate, which is partly modulated by their microbiota. Mosquito microbiota is acquired during the larval phase and modified during their development and
adult feeding behavior, being highly dependent on environmental factors. Pharmaceutical residues including antibiotics are widespread pollutants potentially being present in mosquito breeding waters likely affecting their microbiota. Here, we used Culex pipiens mosquitoes to assess the impact of antibiotic exposure during the larval and adult stages on the survival rate of adult mosquitoes. Wild-collected larvae were randomly assigned to two treatments: larvae maintained in water supplemented with antibiotics and control larvae. Emerged adults were subsequently assigned to each of two treatments, fed with sugar
solution with antibiotics and fed only with sugar solution (controls). Larval exposure to antibiotics significantly increased the survival rate of adult females that received a control diet. In addition, the effect of adult exposure to antibiotics on the survival rate of both male and female mosquitoes depended on the number of days that larvae fed ad libitum in the laboratory before emergence. In particular, shorter larval ad libitum feeding periods reduced the survival rate of antibiotic-treated adult mosquitoes compared with those that emerged after a longer larval feeding period. These differences were not found in control adult mosquitoes. Our results extend the current understanding of the impact of antibiotic exposure of mosquitoes on a key component of vectorial capacity, that is the vector survival rate.MCIN/AEI/10.13039/501100011033 [grant number PID2020-118205GB-I00]Spanish Ministry of Science and Innovation [grant numbers PRE2021-098544 and FJC2021-048057-I]Spanish Ministry of Universities [Margarita Salas and María Zambrano programs]Funding for open access charge: Universidad de Granada / CBU
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