Remove Noise in Video with 3D Topological Maps

International audienceIn this paper we present a new method for foreground masks denoising in videos. Our main idea is to consider videos as 3D images and to deal with regions in these images. Denoising is thus simply achieved by merging foreground regions corresponding to noise with background regions. In this framework, the main question is the definition of a cri-terion allowing to decide if a region corresponds to noise or not. Thanks to our complete cellular description of 3D images, we can propose an advanced criterion based on Betti numbers, a topological invariant. Our results show the interest of our approach which gives better results than previous methods

Magnon dispersion and thermodynamics in CsNiF_3

We present an accurate transfer matrix renormalization group calculation of the thermodynamics in a quantum spin-1 planar ferromagnetic chain. We also calculate the field dependence of the magnon gap and confirm the accuracy of the magnon dispersion derived earlier through an 1/n expansion. We are thus able to examine the validity of a number of previous calculations and further analyze a wide range of experiments on CsNiF_3 concerning the magnon dispersion, magnetization, susceptibility, and specific heat. Although it is not possible to account for all data with a single set of parameters, the overall qualitative agreement is good and the remaining discrepancies may reflect departure from ideal quasi-one-dimensional model behavior. Finally, we present some indirect evidence to the effect that the popular interpretation of the excess specific heat in terms of sine-Gordon solitons may not be appropriate.Comment: 9 pages 10 figure

The Origin of Intraspecific Variation of Virulence in an Eukaryotic Immune Suppressive Parasite

Occurrence of intraspecific variation in parasite virulence, a prerequisite for coevolution of hosts and parasites, has largely been reported. However, surprisingly little is known of the molecular bases of this variation in eukaryotic parasites, with the exception of the antigenic variation used by immune-evading parasites of mammals. The present work aims to address this question in immune suppressive eukaryotic parasites. In Leptopilina boulardi, a parasitic wasp of Drosophila melanogaster, well-defined virulent and avirulent strains have been characterized. The success of virulent females is due to a major immune suppressive factor, LbGAP, a RacGAP protein present in the venom and injected into the host at oviposition. Here, we show that an homologous protein, named LbGAPy, is present in the venom of the avirulent strain. We then question whether the difference in virulence between strains originates from qualitative or quantitative differences in LbGAP and LbGAPy proteins. Results show that the recombinant LbGAPy protein has an in vitro GAP activity equivalent to that of recombinant LbGAP and similarly targets Drosophila Rac1 and Rac2 GTPases. In contrast, a much higher level of both mRNA and protein is found in venom-producing tissues of virulent parasitoids. The F1 offspring between virulent and avirulent strains show an intermediate level of LbGAP in their venom but a full success of parasitism. Interestingly, they express almost exclusively the virulent LbGAP allele in venom-producing tissues. Altogether, our results demonstrate that the major virulence factor in the wasp L. boulardi differs only quantitatively between virulent and avirulent strains, and suggest the existence of a threshold effect of this molecule on parasitoid virulence. We propose that regulation of gene expression might be a major mechanism at the origin of intraspecific variation of virulence in immune suppressive eukaryotic parasites. Understanding this variation would improve our knowledge of the mechanisms of transcriptional evolution currently under active investigation

High Molecular Weight Hyaluronan Promotes Corneal Nerve Growth in Severe Dry Eyes

The purpose of this study was to investigate the effect of high molecular weight hyaluronan (HMWHA) eye drops on subbasal corneal nerves in patients suffering from severe dry eye disease (DED) and to evaluate the damage of subbasal corneal nerves associated with severe DED. Designed as an international, multicenter study, 16 patients with symptoms of at least an Ocular Surface Disease Index (OSDI) score of 33, and corneal fluorescein staining (CFS) of at least Oxford grade 3, were included and randomized into two study arms. The control group continued to use their individual optimum artificial tears over the study period of eight weeks; in the verum group, the artificial tears were substituted by eye drops containing 0.15% HMWHA. At the baseline visit, and after eight weeks, the subbasal nerve plexus of 16 patients were assessed by confocal laser scanning microscopy (CSLM). The images were submitted to a masked reading center for evaluation. Results showed a significant increase of total nerve fiber lengths (CNFL) in the HMWHA group (p = 0.030) when compared to the control group, where the total subbasal CNFL did not significantly change from baseline to week 8. We concluded that in severe DED patients, HMWHA from topically applied eye drops could cross the epithelial barrier and reach the subbasal nerve plexus, where it exercised a trophic effect

AME position statement on adrenal incidentaloma.

Objective: To assess currently available evidence on adrenal incidentaloma and provide recommendations for clinical practice. Design: A panel of experts (appointed by the Italian Association of Clinical Endocrinologists (AME)) appraised the methodological quality of the relevant studies, summarized their results, and discussed the evidence reports to find consensus. Radiological assessment: Unenhanced computed tomography (CT) is recommended as the initial test with the use of an attenuation value of <= 10 Hounsfield units (HU) to differentiate between adenomas and non-adenomas. For tumors with a higher baseline attenuation value, we suggest considering delayed contrast-enhanced CT studies. Positron emission tomography (PET) or PET/CT should be considered when CT is inconclusive, whereas fine needle aspiration biopsy may be used only in selected cases suspicious of metastases (after biochemical exclusion of pheochromocytoma). Hormonal assessment: Pheochromocytoma and excessive overt cortisol should be ruled out in all patients, whereas primary aldosteronism has to be considered in hypertensive and/or hypokalemic patients. The 1 mg overnight dexamethasone suppression test is the test recommended for screening of subclinical Cushing's syndrome (SCS) with a threshold at 138 nmol/l for considering this condition. A value of 50 nmol/l virtually excludes SCS with an area of uncertainty between 50 and 138 nmol/l. Management: Surgery is recommended for masses with suspicious radiological aspects and masses causing overt catecholamine or steroid excess. Data are insufficient to make firm recommendations for or against surgery in patients with SCS. However, adrenalectomy may be considered when an adequate medical therapy does not reach the treatment goals of associated diseases potentially linked to hypercortisolism

Elastic optical interface with variable baudrate: Architecture and proof-of-concept

Varying the symbol rate is an alternative or complementary approach to varying the modulation format or the channel spacing to turn optical networks into elastic networks. We propose to allocate just-enough bandwidth for each optical connection by adjusting the symbol rate such that the penalty originating from long cascades of optical filters is contained. This helps reduce overprovisioning for lightpaths where full capacity is not needed, by (i) eliminating unnecessary regenerators and (ii) reducing the power consumption of terminals, when the clock rate of electronics is reduced along with the baudrate. We propose a novel architecture for an elastic optical interface by combining a variable bitrate transceiver, paired with an elastic aggregation stage, with software-defined control. We then report a real-Time field-programmable-gate-Array-based prototype that delivers flexible transport frames to be sent with a polarization-division multiplexed quadrature phase-shift keying modulation format. We interconnect this prototype with a commercial optical transport network switch and a centralized controller. We demonstrate fast and hitless reconfiguration of the interface and measure the reconfiguration time of hardware logic ( < 450 μs), as well as end-To-end control and the data plane ( < 0.9 s)

Deciding case by case on family presence in the emergency care service

Objective: To understand how physicians and nurses experience and perceive the presence of families in the emergency care service. Methods: This was a qualitative study that used symbolic interactionism as a theoretical reference, and grounded theory as a methodological reference. Twenty professionals participated – equally representing physicians and nurses - working in two emergency rooms located in the south of Brazil. Data were collected between October of 2016 and February of 2017, by means of interviews. Results: The existence of a social culture of family exclusion was identifi ed, widely diffused and practiced by professionals. However, families sometimes remain with their loved ones in the emergency room, since professionals analyze and decide “case by case”, considering different aspects throughout the care process. Conclusion: Multiple aspects are related in determining family presence during emergency care for physicians and nurses. Thus, a single directive on the presence of the family is not prudent. In fact, it is suggested that each health unit develop its protocols, considering local particularities.Objetivo: Compreender como médicos e enfermeiros vivenciam e percebem a presença da família no serviço de atendimento emergencial. Métodos: Estudo qualitativo que utilizou o Interacionismo Simbólico como referencial teórico e a Teoria Fundamentada nos Dados como referencial metodológico. Participaram 20 profi ssionais – divididos equitativamente entre médicos e enfermeiros – que atuavam em duas Salas de Emergência localizadas no Sul do Brasil. Os dados foram coletados entre outubro de 2016 e fevereiro de 2017, por meio de entrevistas. Resultados: Identifi cou-se a existência de uma cultura social de exclusão familiar, amplamente difundida e praticada pelos profi ssionais. Contudo, às vezes, as famílias permanecem com seus entes queridos na Sala de Emergência, visto que os profi ssionais analisam e decidem “caso a caso”, considerando diferentes aspectos ao longo do processo assistencial. Conclusão: Para médicos e enfermeiros múltiplos aspectos estão relacionados na determinação da presença familiar durante o atendimento emergencial. Assim, não é aconselhável uma diretiva única para a presença da família. Em realidade, sugere-se que cada unidade de saúde elabore seus protocolos considerando as particularidades locais.Objetivo: Comprender cómo médicos y enfermeros experimentan y perciben la presencia familiar en el servicio de atención de urgencias. Métodos: Estudio cualitativo, aplicando el Interaccionismo Simbólico como referencial teórico, y la Teoría Fundamentada en los Datos como referencial metodológico. Participaron 20 profesionales –equitativamente divididos entre médicos y enfermeros– actuantes en dos Servicios de Urgencias del Sur de Brasil. Datos recolectados de octubre 2016 a febrero 2017 mediante entrevistas. Resultados: Se identifi có la existencia de una cultura social de exclusión familiar, ampliamente difundida y practicada por los profesionales. Igualmente, a veces, las familias permanecen con sus seres queridos en el Servicio de Urgencias, dado que los profesionales analizan y deciden “caso por caso”, considerando diferentes aspectos a lo largo del proceso de atención. Conclusión: Para médicos y enfermeros, múltiples aspectos se relacionan con la determinación de la presencia familiar durante la atención de urgencia. Por ello, no es aconsejable una directiva única sobre presencia familiar. En realidad, se sugiere que cada unidad de salud elabore sus protocolos considerando sus propias características

Nonlinear excitations in CsNiF3 in magnetic fields perpendicular to the easy plane

Experimental and numerical studies of the magnetic field dependence of the specific heat and magnetization of single crystals of CsNiF3 have been performed at 2.4 K, 2.9 K, and 4.2 K in magnetic fields up to 9 T oriented perpendicular to the easy plane. The experimental results confirm the presence of the theoretically predicted double peak structure in the specific heat arising from the formation of nonlinear spin modes. The demagnetizing effects are found to be negligible, and the overall agreement between the data and numerical predictions is better than reported for the case when the magnetic field was oriented in the easy plane. Demagnetizing effects might play a role in generating the difference observed between theory and experiment in previous work analyzing the excess specific heat using the sine-Gordon model.Comment: 6 pages, 5 figures, submitted to Phys. Rev.