3,932 research outputs found
Dark Side Augmentation: Generating Diverse Night Examples for Metric Learning
Image retrieval methods based on CNN descriptors rely on metric learning from
a large number of diverse examples of positive and negative image pairs.
Domains, such as night-time images, with limited availability and variability
of training data suffer from poor retrieval performance even with methods
performing well on standard benchmarks. We propose to train a GAN-based
synthetic-image generator, translating available day-time image examples into
night images. Such a generator is used in metric learning as a form of
augmentation, supplying training data to the scarce domain. Various types of
generators are evaluated and analyzed. We contribute with a novel light-weight
GAN architecture that enforces the consistency between the original and
translated image through edge consistency. The proposed architecture also
allows a simultaneous training of an edge detector that operates on both night
and day images. To further increase the variability in the training examples
and to maximize the generalization of the trained model, we propose a novel
method of diverse anchor mining.
The proposed method improves over the state-of-the-art results on a standard
Tokyo 24/7 day-night retrieval benchmark while preserving the performance on
Oxford and Paris datasets. This is achieved without the need of training image
pairs of matching day and night images. The source code is available at
https://github.com/mohwald/gandtr .Comment: 11 pages, 4 figures, 8 table
Transience and constancy of interactions in a plant-frugivore network
Plant-animal mutualistic interactions such as frugivory and seed dispersal display great variation in time due to fluctuations in fruit abundance, animal abundance, and behavior. In particular, some species participate in interactions with other species only transiently, while other species are active for longer periods of time. Species with a longer period of activity are able to interact with more species, and thus engage in constant participation in an interaction network. Species with high constancy would thus be expected to help maintain the biodiversity of a community; however, the manner in which constant species link to their partners may be critical to species coexistence. Because species that interact with many partners concurrently could create more competition compared to those species that interact sequentially with many partners, evaluating the concurrence in an interaction network sheds light on how the network can maintain biodiversity. In this study, we investigate how phenological patterns of fruit production and frugivore presence affect the temporal variation of a plant-frugivore network, and focus on the manner in which high degree species collect their interactions over time. We found a clear separation of activity periods: most species appeared only briefly and participated in relatively few interactions, or showed activity for longer time periods and participated in more interactions. Species that were active for longer time periods often shifted interactions, resulting in a sequential collection of their partners in time, rather than concurrence. For the seed dispersal mutualism in particular, sequential accumulation of partners may allow plant species more opportunities to disperse their seeds compared to concurrence. We suggest that for temporally and spatially heterogeneous landscapes, sequential accumulation of partners would serve to reduce competition and facilitate coexistence of species. Copyright © 2013 Yang et al
Flash suppression and flash facilitation in binocular rivalry
We show that previewing one half image of a binocular rivalry pair can cause it to gain initial dominance when the other half is added, a novel phenomenon we term flash facilitation. This is the converse of a known effect called flash suppression, where the previewed image becomes suppressed upon rivalrous presentation. The exact effect of previewing an image depends on both the duration and the contrast of the prior stimulus. Brief, low-contrast prior stimuli facilitate, whereas long, high-contrast ones suppress. These effects have both an eye-based component and a pattern-based component. Our results suggest that, instead of reflecting two unrelated mechanisms, both facilitation and suppression are manifestations of a single process that occurs progressively during presentation of the prior stimulus. The distinction between the two phenomena would then lie in the extent to which the process has developed during prior stimulation. This view is consistent with a neural model previously proposed to account for perceptual stabilization of ambiguous stimuli, suggesting a relation between perceptual stabilization and the present phenomena
FULL POPULATION TESTING FOR VALIDATION OF HUMAN RESTRAINT SYSTEMS ON COMMERCIAL AND NON COMMERCIAL ERGOMETERS
Human missions to Mars is one of the main objectives for scientific space international community and major goals on physiological and biomechanical space research is reduction of muscle atrophy (Fitts, 2000; Zange, 1997). MARES (Muscular Atrophy Research and Exercise System) system is an ergometer to be flown and installed in the International Space Station in the year 2007. This system will allow neuromuscular and gravitational physiology research on orbit. MARES consists of a control electronics that drives a motor, to which a subject .is connected by means of a restraining system named HRS (Human Restraint System). This ergometer can be programmed to work in 14 different modes (Isometric, Isotonic, Isokinetic, Spring, Friction, Additional Moment of Inertia/Mass, Pseudogravitational, Position Control, Velocity Control, Torque/Force Control, Power Control, Physical Elements, Extended Torque/Force Control, Quick Release). All of this modes are available for 11 movements, corresponding to main body joints and movements
Circadian Patterns of Patients with Type 2 Diabetes and Obstructive Sleep Apnea
Índex d’apnea-hipopnea; Circadià; Hemoglobina glicadaÍndice de apnea-hipopnea; Circadiano; Hemoglobina glicadaApnea-hypoapnea index; Circadian; Glycated hemoglobinSleep apnea, a condition that modifies sleep and circadian rhythms, is highly prevalent in patients with diabetes. However, it is not known if there is an association between sleep apnea, circadian alterations and glycemic regulation in this type of patient. Here, a polysomnographic study was carried out on 21 women and 25 men (mean age = 64.3 ± 1.46 years) with diagnoses of type 2 diabetes to detect the presence of sleep apnea. Moreover, patients wore an actigraph and a temperature sensor on the wrist for one week, to study the manifestation of the circadian rhythms. The correlations of circadian and polysomnographic variables with the severity of apnea, measured by the apnea-hypopnea index, and with glycemic dysregulation, measured by the percentage of glycated hemoglobin, were analyzed. The mean apnea-hypoapnea index of all the participants was 39.6 ± 4.3. Apnea-hypoapnea index correlated with % N1, negatively with % N3, and also the stability of the active circadian rhythm. However, no significant correlation was found between the apnea-hypopnea index and wrist temperature rhythm and glycated hemoglobin. Glycated hemoglobin levels were negatively associated with the percentage of variance explained by the wrist temperature circadian rhythm (calculated via 24 and 12 h rhythms). This association was independent of body mass index and was strongest in patients with severe apnea. In conclusion, patients with diabetes showed altered circadian rhythms associated with a poor glycemic control and this association could partially be related to the coexistence of sleep apnea.This research was supported by grants from de Instituto de Salud Carlos III ISCIII (Fondo de Investigación Sanitaria PI12/00803 and PI15/00260). European Union (European Regional Development Fund. Fondo Europeo de Desarrollo Regional. FEDER. “Una manera de hacer Europa”). CIBER de Diabetes y Enfermedades Metabólicas Asociadas and CIBER de Enfermedades Respiratorias are initiatives of the Instituto de Salud Carlos III
Genomic Imprinting Mediates Social Interactions Within Honeybee (Apis mellifera) Colonies.
Patient centeredness means providing care that is respectful of and responsive to individual patient preferences, needs and values, and ensuring that patient values guide all clinical decisions’.The concept assumes that both physicians and patients are experts; physicians in diagnostic and therapeutic procedures, patients by their personal experience. Van der Eijk examined how patient-centeredness could be defined, measured and improved in Parkinson care. Patients with Parkinson's disease(PD) become progressively disabled due to a mixture of cognitive, emotional and motor symptoms. Given the complex nature of the disease, delivering patient-centered care to PD patients is challenging. Preferably, Parkinson care is provided by a collaborative team of physicians, nurses, psychosocial caregivers and allied health experts. 'Patient-centeredness' implies that patients are invited to participate within this team. PD patients currently assume a passive role in healthcare, partially because this is the traditional approach, but also because they lack the tools to self-manage their condition. Van der Eijk found out that PD patients experience a lack of collaboration between their healthcare professionals. Additionally, patients urgently call for more and personally tailored information as well as emotional support to cope better with their disease. Van der Eijk collected patient-experiences in the Netherlands, Canada and the United States and evaluated regional multidisciplinary healthcare networks and online health communities. These innovations may improve the patient-centeredness of care and enhance communication among health professionals and patients, and support coordination of care across institutions. A personal health community is a private community governed by individual patients. Apart from the patient, participants include the caregiver and one or more (ideally all) health professionals involved. Patients favor the possibility to interact with their health professionals for emotional support and to obtain medical information. When technically well facilitated, the concept stimulates active patient involvement in their own health and healthcare
Simbiosis bacteriana y conservación de flora amenazada: el caso del Lupinus mariae-josephae.
Lupinus mariae-josephae H. Pascual es un altramuz endémico de un reducido número de sitios en la Comunidad Valenciana, donde coloniza sustratos de ?terra rossa? sobre afloramientos de lapiaz. Descrito en 2004 a partir de plantas cultivadas, no pudo localizarse en campo hasta 2006, y el hallazgo de sus poblaciones ha estado estrechamente ligado a topónimos relativos a su nombre popular, ?tramús? en valenciano. Se ha demostrado la clara independencia genética, y en consecuencia el valor como ?buen taxon? de esta especie. Hasta ahora se han caracterizado y censado cinco poblaciones silvestres en diferentes localidades, y en todas ellas se observan fuertes fluctuaciones interanuales de sus efectivos, a veces acompañadas de importantes diferencias de vigor de los ejemplares; tres de estas poblaciones están actualmente protegidas mediante sendas microrreservas de flora. Algunos de estos núcleos poblacionales se componen en años concretos de formas poco vigorosas, que a menudo sólo producen 1-2 frutos con 1-2 semillas; por el contrario, las formas más vigorosas pueden producir varias docenas de semillas. La emergencia de plántulas se produce con gran probabilidad tras años de progresiva escarificación de la cubierta de las semillas en el suelo, y probablemente se acelera por procesos de reducción de la cubierta vegetal como los incendios forestales. La germinación experimental ex situ sólo se consigue satisfactoriamente mediante el pretratamiento de escaldado de las semillas
Human Respiratory Syncytial Virus Memphis 37 Grown in HEp-2 Cells Causes more Severe Disease in Lambs than Virus Grown in Vero Cells
Respiratory syncytial virus (RSV) is the most common cause of bronchiolitis in infants and young children. A small percentage of these individuals develop severe and even fatal disease. To better understand the pathogenesis of severe disease and develop therapies unique to the less-developed infant immune system, a model of infant disease is needed. The neonatal lamb pulmonary development and physiology is similar to that of infants, and sheep are susceptible to ovine, bovine, or human strains of RSV. RSV grown in Vero (African green monkey) cells has a truncated attachment G glycoprotein as compared to that grown in HEp-2 cells. We hypothesized that the virus grown in HEp-2 cells would cause more severe clinical symptoms and cause more severe pathology. To confirm the hypothesis, lambs were inoculated simultaneously by two different delivery methods (intranasal and nebulized inoculation) with either Vero-grown or HEp-2-grown RSV Memphis 37 (M37) strain of virus to compare viral infection and disease symptoms. Lambs infected with HEp-2 cell-derived virus by either intranasal or nebulization inoculation had significantly higher levels of viral RNA in lungs as well as greater clinical disease including both gross and histopathologic lesions compared to lambs similarly inoculated with Vero-grown virus. Thus, our results provide convincing in vivo evidence for differences in viral infectivity that corroborate previous in vitro mechanistic studies demonstrating differences in the G glycoprotein expression by RSV grown in Vero cells
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