Spin torque driven dynamics of a coupled two layer structure: interplay between conservative and dissipative coupling

In this manuscript the general concepts of spin wave theory are adapted to the dynamics of a self-polarized system based on two layers coupled via interlayer exchange (conservative coupling) and mutual spin torque (dissipative coupling). An analytical description of the non-linear dynamics is proposed and validated through numerical simulations. In contrast to the single layer model, the phase equation of the coupled system has a contribution coming from the dissipative part of the LLGS equation. It is shown that this is a major contribution to the frequency mandatory to describe well the most basic features of the dynamics of coupled systems. Using the proposed model a specific feature of coupled dynamics is addressed: the redshift to blueshift transition observed in the frequency current dependence of this kind of exchange coupled systems upon increasing the applied field. It is found that the blueshift regime can only occur in a region of field where the two linear eigenmodes contribute equally to the steady state mode (i.e. high mode hybridization). Finally, a general perturbed Hamiltonian equation for the coupled system is proposed.Comment: 16 pages, 7 figue

Primary endometrial carcinoma with signet-ring cells. A case report and review of the literature

Endometrial adenocarcinoma with signet-ring cells is an infrequent histological type of carcinoma that usually corresponds to a metastasis of a primary carcinoma of another origin, mainly from the gastrointestinal tract or the breast. For this reason, in view of this histological finding, it is essential to carry out a thorough evaluation including mammography, gastroscopy, colonoscopy and thoracoabdominopelvic CT. To date, only six cases of primary endometrial carcinoma with signet-ring cells have been reported in the English literature. A 73-year-old patient was referred to the Gynecology Department with a 3-day history of postmenopausal bleeding. She was diagnosed with primary endometrial adenocarcinoma with signet-ring cells. The anatomopathological special features of the surgical specimen are presented, as well as the evolution of the patient, who remained asymptomatic and free of disease 28 months after surgery. A review of the literature is performed, emphasizing the peculiarities of this rare histological subtype. Despite the fact that primary endometrial carcinoma with signet-ring cells is an infrequent tumor, it must be considered in the differential diagnosis of malignant tumors of aforesaid origin. It is essential to carry out a correct and an extensive investigative study as well as an immunohistochemical analysis of the samples obtained for its confirmation diagnosis

Long-term fire resilience of the Ericaceous Belt, Bale Mountains, Ethiopia

Fire is the most frequent disturbance in the Ericaceous Belt (ca 3000- 4300 m.a.s.l.), one of the most important plant communities of tropical African mountains. Through resprouting after fire, Erica establishes a positive fire feedback under certain burning regimes. However, present-day human activity in the Bale Mountains of Ethiopia includes fire and grazing systems that may have a negative impact on the resilience of the ericaceous ecosystem. Current knowledge of Erica-fire relationships is based on studies of modern vegetation, lacking a longer time perspective that can shed light on baseline conditions for the fire feedback. We hypothesize that fire has influenced Erica communities in the Bale Mountains at millennial timescales. To test this, we (1) identify the fire history of the Bale Mountains through a pollen and charcoal record from Garba Guracha, a lake at 3950 m.a.s.l., and (2) describe the long-term bidirectional feedback between wildfire and Erica, which may control the ecosystem's resilience. Our results support fire occurrence in the area since ca 14 000 years ago, with particularly intense burning during the early Holocene, 10.8-6.0 cal ka BP. We show that a positive feedback between Erica abundance and fire occurrence was in operation throughout the Lateglacial and Holocene, and interpret the Ericaceous Belt of the Ethiopian mountains as a long-term fire resilient ecosystem. We propose that controlled burning should be an integral part of landscape management in the Bale Mountains National Park

Zero-Shot Hashing via Transferring Supervised Knowledge

Hashing has shown its efficiency and effectiveness in facilitating large-scale multimedia applications. Supervised knowledge e.g. semantic labels or pair-wise relationship) associated to data is capable of significantly improving the quality of hash codes and hash functions. However, confronted with the rapid growth of newly-emerging concepts and multimedia data on the Web, existing supervised hashing approaches may easily suffer from the scarcity and validity of supervised information due to the expensive cost of manual labelling. In this paper, we propose a novel hashing scheme, termed \emph{zero-shot hashing} (ZSH), which compresses images of "unseen" categories to binary codes with hash functions learned from limited training data of "seen" categories. Specifically, we project independent data labels i.e. 0/1-form label vectors) into semantic embedding space, where semantic relationships among all the labels can be precisely characterized and thus seen supervised knowledge can be transferred to unseen classes. Moreover, in order to cope with the semantic shift problem, we rotate the embedded space to more suitably align the embedded semantics with the low-level visual feature space, thereby alleviating the influence of semantic gap. In the meantime, to exert positive effects on learning high-quality hash functions, we further propose to preserve local structural property and discrete nature in binary codes. Besides, we develop an efficient alternating algorithm to solve the ZSH model. Extensive experiments conducted on various real-life datasets show the superior zero-shot image retrieval performance of ZSH as compared to several state-of-the-art hashing methods.Comment: 11 page

Interacción genotipo-manejo de la alimentación en la producción de pollos camperos

Poultry meat production in semi-intensive management systems is an ecological modality that takes into account aspects related to animal welfare. Campero chicken is a bird with a slower growth rate than commercial broilers destined to the production of meat in this type of systems. The traditional feeding scheme includes the use of three types of food specially formulated for this purpose (starter, grower and finisher) which introduces management complications, particularly in relation to the availability of grower food for small producers. An alternative that would facilitate feeding management is a scheme based on only two types of food: starter and finisher. The aim of this work was to evaluate the effect of changing the traditional feeding scheme by an alternative one, replacing grower food with a mix of starter and finisher, in two genotypes of chicken with a different growth rate: the experimental three-way cross Campero Casilda and the two-way cross Campero INTA. The evidence indicates that the proposed change in the traditional feeding management does not affect body growth, feed conversion ratio and productive traits at slaughter, and that both genetic groups behave similarly, when grower diet is replaced by a mix of starter and finisher.La producción de carne aviar en sistemas de manejo semi-intensivo es una modalidad ecológica que contempla aspectos vinculados con el bienestar animal. El pollo Campero es un ave con menor velocidad de crecimiento que los parrilleros comerciales, destinado a la producción de carne. El esquema tradicional de alimentación incluye la utilización de tres tipos de alimentos especialmente formulados a tal fin (iniciador, crecimiento y terminador), lo cual introduce complicaciones en el manejo, particularmente en lo referido a la disponibilidad del alimento “crecimiento” para los pequeños productores. Una alternativa que facilitaría el manejo de estas aves es un esquema basado en sólo dos tipos de alimentos: iniciador y terminador. El objetivo de este trabajo fue evaluar el efecto del cambio del manejo tradicional de la alimentación por uno alternativo reemplazando el alimento “crecimiento” por una mezcla de iniciador y terminador, en dos genotipos de pollo Campero con diferente velocidad de crecimiento: el híbrido experimental de tres vías Campero Casilda y el híbrido simple Campero INTA. La evidencia indicó que el cambio en el manejo de la alimentación no afectó el crecimiento, la relación de conversión ni los caracteres a la faena. Ambos grupos genéticos se comportaron de manera equivalente, pudiendo obviarse la inclusión de la categoría “crecimiento” si se la reemplaza por una mezcla de iniciador y terminador

Quantum properties of classical Fisher information

The Fisher information of a quantum observable is shown to be proportional to both (i) the difference of a quantum and a classical variance, thus providing a measure of nonclassicality; and (ii) the rate of entropy increase under Gaussian diffusion, thus providing a measure of robustness. The joint nonclassicality of position and momentum observables is shown to be complementary to their joint robustness in an exact sense.Comment: 16 page