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I de Nigro fra Due e Trecento: progetti familiari e modalità consociative di un albergo genovese. Prime ricerche
Get PDFBenché gli alberghi siano uno dei tratti più originali e distintivi della Genova tardomedievale, queste consociazioni familiari sono state poco considerate dagli studiosi della città ligure. A fronte della necessità di riprendere il problema e di riorientare l’attenzione verso gli aspetti interni della città, questo saggio offre una prima panoramica sulle vicende dell’albergo de Nigro a partire dalle prime attestazioni relative alla famiglia nel secolo XII. La vasta messe di documentazione notarile che li riguarda mostra un gruppo parentale coeso i cui membri, oltre all’interesse verso il commercio, hanno anche una spiccata inclinazione verso la carriera giuridica
Selective photocatalytic oxidation of 5-hydroxymethyl-2-furfural in aqueous suspension of polymeric carbon nitride and its adduct with H2O2 in a solar pilot plant
No full textThis work reports a study on the reactivity of polymeric carbon nitride (PCN) and PCN-H2O2 adduct samples for sunlight photocatalytic selective oxidation reactions. The characterization of these materials was reported in a previous paper where the reactivity towards the partial oxidation of 5-hydroxymethylfurfural (HMF) was studied by using two different laboratory scale photoreactors; one irradiated by UV lamps and the other one by natural sunlight. In the present study it has been confirmed the effectiveness of these C3N4 based materials for the selective partial oxidation of HMF to FDC (2,5-furandicarboxaldehyde) in aqueous medium in a pilot plant photoreactor irradiated by natural sunlight. The reactivity results and, in particular, the selectivity to FDC formation have been very encouraging, mostly by considering that the reaction was carried out in water. Moreover, they are comparable with those obtained in the laboratory scale photoreactors irradiated by both UV lamps and natural sunlight. Interestingly, the pristine PCN sample has shown a higher HMF conversion with respect to that of the PCN-H2O2 adduct, but the last one is more selective to the FDC formation. A kinetic study indicates that the pseudo-first-order rate constant of HMF oxidation is higher in the case of pristine photocatalyst and that the equilibrium adsorption constants of HMF is higher in the case of PCN-H2O2 adduct catalyst. Finally, the partial oxidation of two aromatic alcohols, i.e. benzyl alcohol (BA) and 4-methoxy benzyl alcohol (4-MBA) to benzaldehyde (BAL) and 4-methoxy benzaldehyde (4-MBAL), respectively, has also been studied
Saberes y prácticas de una población rural maya con diabetes tipo 2 sobre plantas medicinales
No full textObjective: To explore the knowledge and practices that are developed from the experiences of the use of medicinal plants in people with DT2 of a Mayan community of Yucatán, Mexico. Method: qualitative research that took place in Tekit, Yucatán, using a semi structured survey with snowball sampling until theorical saturation is reached. Data analysis was performed though Janice Morse’s cognitive process. Results: theorical saturation was obtained with eight participants. Six categories were identified. One of them refers to plants utilized has an hypoglycemia effect identifying 22 plants according to Mayan population, others refers to experience and use reasons, knowledge transfer, relations with health personnel and faith related practices. Findings: Traditional medicine is an option of health care for the person living with type 2 diabetes in Tekit, Yucatan, Mexico due to the difficulty in attention for various factors; it could be used as a therapeutic option for the search of a cure to the disease and / or Cease symptoms. The health professional in the indigenous communities must approach a cultural understanding to be involved in self-management of health by understanding the practices and apply it in comprehensive care with a purpose of improving attention in healthcare services.Objetivo: Describir los saberes y prácticas en el uso de plantas medicinales para el control de la diabetes tipo 2 en pobladores de una comunidad rural. Método: Estudio cualitativo, con enfoque fenomenológico; participaron 8 personas con diabetes tipo 2 de una comunidad rural maya de Tekit, Yucatán, a quienes se les realizó una entrevista semiestructurada. La información fue analizada mediante el proceso cognitivo de Morse hasta la saturación de datos. Resultados: se obtuvo la categoría central “saberes y prácticas sobre plantas medicinales para el control y las complicaciones de la diabetes” y seis subcategorías: saberes para el control de la glucosa, prácticas tradicionales ante problemas ocasionados por la enfermedad, efectividad sanadora de las plantas, transmisión de saberes, factores que influyen en el uso y respeto a las prácticas tradicionales por los profesionales de salud. Conclusión: La herbolaria es un factor importante para la recuperación y conservación de la salud en la población de estudio, además representa un elemento que fortalece su identidad cultural como pueblo maya yucateco, pues forma parte de su tradición. El cuidado enfermero con enfoque cultural es necesario para el entendimiento y comprensión de las prácticas de la herbolaria y se debe incorporar en la atención integral a la persona
El gorgojo de la flor del manzano: ¿un problema para las pumaradas de Asturias?
No full textEn el primer estudio sobre la importancia del gorgojo de la flor como plaga de los manzanos de sidra en Asturias,
identificamos los factores que regulan su nivel de infestación y los agentes de su control biológico. Nuestros
resultados muestran que el ataque del gorgojo depende de características de la propia pumarada y del paisaje
circundante que reflejan la disponibilidad de recursos (alimento, reproducción y refugio) para el insecto. También
descubrimos que tres tipos de enemigos naturales (parasitoides, aves y artrópodos depredadores) se complementan
para atacar a los gorgojos en diferentes etapas de su ciclo de vida
Aplicación del análisis de imágenes en la caracterizacion del fruto de variedades de arándano
No full textEl fruto del arándano (Vaccinium spp)
es una baya de color azul dispuesto en racimos
más o menos densos. En el mercado
hay numerosas variedades disponibles
que habitualmente se clasifican atendiendo
a la especie (Vaccinium corymbosum
L., Vaccinium virgatum Aiton, o híbridos
interespecíficos), a sus requerimientos en
horas de frío (mayor o menor de 700 horas)
o a la época de producción (temprano,
temporada o tardío). Sólo en la Oficina Comunitaria
de Variedades Vegetales se han
registrado 117 variedades de Vaccinium
corymbosum L., 12 de Vaccinium virgatum
Aiton y 11 híbridos de V. corymbosum x
Vaccinium angustifolium Aito
Control de plagas del manzano de sidra por aves silvestres
No full textMediante experimentos de campo, demostramos el importante papel de las
aves insectívoras como predadores de artrópodos del manzano de sidra de
Asturias. La presencia de aves en las pumaradas reduce notoriamente la cantidad
y el daño de insectos plaga en el manzano. Eso sucede incluso teniendo
en cuenta que algunos de los artrópodos consumidos por las aves son, a su vez,
potenciales predadores de las plagas. Aves y artrópodos auxiliares actúan,
en cualquier caso, de forma aditiva y complementaria sobre las plagas del
manzano. La biodiversidad animal en las pumaradas asturianas proporciona,
por tanto, un notorio servicio ecosistémico de control biológico de plaga
A family of high frequency AC-LED drivers based on ZCS-QRCs
No full textA family of dimmable AC-LED drivers fed from dc voltages, is presented in this paper based on Zero Current Switching Quasi-Resonant Converters (ZCS-QRCs). The proposed family of drivers is based on replacing the diode in conventional converter topologies (i.e. buck, boost or buck-boost) by a string of High-Brightness Light-Emitting Diodes (HB-LED). Hence, the HB-LED string will be working as the rectifier diode and the load, switching at the same frequency of the main switch. In this case, the output current, which is experimentally validated, shows a negative current peak due to the reverse-recovery effect of the HB-LEDs. In order to reduce the reverse-recovery effect on the HB-LEDs, the main switch of the proposed topologies is replaced with a full-wave resonant switch, which makes possible to reduce the di/dt during the turn-off of the HB-LED string, therefore the reverse recovery effect is eliminated. Moreover, the dimming of the HB-LEDs is done by means of changing the switching frequency of the converter, by varying the turn-off while keeping a constant turn-on time. In order to validate the analysis, the proposed topologies have been experimentally tested on a constructed prototype with an output power of 7.5 W.This work has been supported in part by the Spanish Government under Project MINECO-13-DPI2013-47176-C2-2-R and the Principality of Asturias under the grants “Severo Ochoa” BP14-140 and BP14-85, Project FC-15-GRUPIN14-143 and Project SV-PA-17-RIS3-4, and in part by European Regional Development Fund (ERDF) grant
[REVEAL]Editor de entornos virtuales para entrenamiento de algoritmos de visión artificial
No full textResultados del proyecto REVEALResults of the REVEAL projec