Search results for "Pere"
showing 10 items of 632 documents
Time-resolved Observation and Control of Superexchange Interactions with Ultracold Atoms in Optical Lattices
2007
Quantum mechanical superexchange interactions form the basis of quantum magnetism in strongly correlated electronic media. We report on the direct measurement of superexchange interactions with ultracold atoms in optical lattices. After preparing a spin-mixture of ultracold atoms in an antiferromagnetically ordered state, we measure a coherent superexchange-mediated spin dynamics with coupling energies from 5 Hz up to 1 kHz. By dynamically modifying the potential bias between neighboring lattice sites, the magnitude and sign of the superexchange interaction can be controlled, thus allowing the system to be switched between antiferromagnetic or ferromagnetic spin interactions. We compare our…
Ecological and agronomic importance of the plant genus Lotus. Its application in grassland sustainability and the amelioration of constrained and con…
2010
The genus Lotus comprises around 100 annual and perennial species with worldwide distribution. The relevance of Lotus japonicus as a model plant has been recently demonstrated in numerous studies. In addition, some of the Lotus species show a great potential for adaptation to a number of abiotic stresses. Therefore, they are relevant components of grassland ecosystems in environmentally constrained areas of several South American countries and Australia, where they are used for livestock production. Also, the fact that the roots of these species form rhizobial and mycorrhizal associations makes the annual L. japonicus a suitable model plant for legumes, particularly in studies directed to r…
La enseñanza basada en preguntas : La ley de Ampère y el término de Maxwell
2020
Frecuentemente a los maestros de Física y de Matemáticas se les recomienda una enseñanza activa de estas áreas del conocimiento, que consiste en una interacción continua entre el maestro y el estudiante. Con una metáfora de un interrogatorio adecuado, se pretende mostrar al docente una manera de orientar al estudiante en su aprendizaje, motivándolo a recuperar conocimientos previos o causándole un conflicto cognitivo que lo lleve a reformular su aprendizaje. Esta manera de proceder didácticamente se ha llamado enseñanza basada en preguntas, cuya primera referencia histórica nos remite a la Grecia antigua. En este trabajo se presenta la enseñanza de la ley de Ampère con la generalización de …
Loores a San Peregrin, confesor, de la Orden de los Siervos de María Santísima, venerado en el Convento de Religiosas del Pie de la Cruz de la Ciudad…
El full orlat Grav. xil. enmarcat del sant, flanquejat per gerros amb flors El text del goig a tres col. separades per filets
Loores al beato Peregrin, confessor, de la Orden de los Siervos de María Santissima, venerado en el Convento de Religiosas del pie de la Cruz, de la …
El full orlat Grav. xil. enmarcat de "S. Pelegri", flanquejat per gerros amb flors El text del goig a tres col. separades per filets
La responsabilidad Social Empresarial: un valor intangible y factor determinante de competitividad en las PYMES
2016
Male breast cancer.
2010
Male breast cancer (MaleBC) is a rare disease, accounting for <1% of all male tumors. During the last few years, there has been an increase in the incidence of this disease, along with the increase in female breast cancer (FBC). Little is known about the etiology of MaleBC: hormonal, environmental and genetic factors have been reported to be involved in its pathogenesis. Major risk factors include clinical disorders carrying hormonal imbalances, radiation exposure and, in particular, a positive family history (FH) for BC, the latter suggestive of genetic susceptibility. Rare mutations in high-penetrance genes (BRCA1 and BRCA2) confer a high risk of BC development; low-penetrance gene mutati…
A new tetranuclear defective dicubane azide-bridged cobalt(II) complex
2013
Abstract The new tetranuclear cobalt(II) complex with formula [Co4(N3)8(4,5-diazafluoren-9-one)4] (1) is reported. Complex 1 is a cobalt(II) defective dicubane azide-bridged compound showing only azido bridging ligands in the μ1,1– and μ1,1,1– coordination modes. The magnetic properties of 1 are reported. Magnetic susceptibility measurements indicate ferromagnetic coupling. The magnetic data have been fitted to 2 K by considering two different superexchange coupling constants. The out-of-phase signal χM″ displays frequency-dependence below approximately 9 K.
FATIGUE CRACK PROPAGATION THROUGH AUSTEMPERED DUCTILE IRON MICROSTRUCTURE
2010
Austempered ductile iron (ADI) has a wide range of application, particularly for castings used in automotive and earth moving machinery industries. These components are usually subjected to variable dynamic loading that may promote initiation and propagation of fatigue cracks up to final fracture. Thus, it is important to determine the fatigue crack propagation behavior of ADI. Since fatigue crack growth rate (da/dN) vs. stress intensity factor K data describe fatigue crack propagation resistance and fatigue durability of structural materials, da/dN vs. Ka curves of ADI 1050 are reported here. The threshold amplitude of stress intensity factor Kath is also determined. Finally, the influence…
Non-specific bronchial hyper-responsiveness in children with allergic rhinitis: relationship with the atopic status
2003
An increased prevalence of bronchial hyper-responsiveness (BHR) has been demonstrated in children from a general population, and in non-asthmatic adults with allergic rhinitis. Thus, also children with allergic rhinitis are expected to be at higher risk of BHR. We evaluated the prevalence of BHR in a sample of non-asthmatic children with allergic rhinitis by means of the methacholine (Mch) bronchial challenge, and by monitorizing the airway patency using the daily peak expiratory flow variability (PEFv). Fifty-one children (ranged 6-15 years of age) with allergic rhinitis, ascertained by skin prick test to inhalant allergens, underwent a 14-day peak expiratory flow monitoring, and a Mch bro…