Nearfield Acoustic Holography using sparsity and compressive sampling principles

Regularization of the inverse problem is a complex issue when using Near-field Acoustic Holography (NAH) techniques to identify the vibrating sources. This paper shows that, for convex homogeneous plates with arbitrary boundary conditions, new regularization schemes can be developed, based on the sparsity of the normal velocity of the plate in a well-designed basis, i.e. the possibility to approximate it as a weighted sum of few elementary basis functions. In particular, these new techniques can handle discontinuities of the velocity field at the boundaries, which can be problematic with standard techniques. This comes at the cost of a higher computational complexity to solve the associated optimization problem, though it remains easily tractable with out-of-the-box software. Furthermore, this sparsity framework allows us to take advantage of the concept of Compressive Sampling: under some conditions on the sampling process (here, the design of a random array, which can be numerically and experimentally validated), it is possible to reconstruct the sparse signals with significantly less measurements (i.e., microphones) than classically required. After introducing the different concepts, this paper presents numerical and experimental results of NAH with two plate geometries, and compares the advantages and limitations of these sparsity-based techniques over standard Tikhonov regularization.Comment: Journal of the Acoustical Society of America (2012

Coordinating density; working through conviction, suspicion and pragmatism

Achieving higher density development has become, as part of sustainable development, a core principle of the contemporary planning professional. The appeal of density is its simplicity, it is an independent measurable element to which various separate claims can be and are attached; it achieves greater public transport use, makes it possible to live nearer to work, supports mixed uses providing a more lively street-scene and so on. As the academic literature has shown the reality is much more complex as achieving a positive outcome through adjustments to density may lead to negative outcomes elsewhere; it can allow more people to live near public transport nodes but can be detrimental in terms of housing affordability for example. Given this tension between the simplicity of the claims and the complexity of application we are interested in how planners seek to balance the multiple advantages and disadvantages of density; to what extent do they approach density as a simple variable or as a complex act of balancing. We address this question by looking at four higher density developments in London

HSV-1 genome subnuclear positioning and associations with host-cell PML-NBs and centromeres regulate LAT locus transcription during latency in neurons.

Major human pathologies are caused by nuclear replicative viruses establishing life-long latent infection in their host. During latency the genomes of these viruses are intimately interacting with the cell nucleus environment. A hallmark of herpes simplex virus type 1 (HSV-1) latency establishment is the shutdown of lytic genes expression and the concomitant induction of the latency associated (LAT) transcripts. Although the setting up and the maintenance of the latent genetic program is most likely dependent on a subtle interplay between viral and nuclear factors, this remains uninvestigated. Combining the use of in situ fluorescent-based approaches and high-resolution microscopic analysis, we show that HSV-1 genomes adopt specific nuclear patterns in sensory neurons of latently infected mice (28 days post-inoculation, d.p.i.). Latent HSV-1 genomes display two major patterns, called "Single" and "Multiple", which associate with centromeres, and with promyelocytic leukemia nuclear bodies (PML-NBs) as viral DNA-containing PML-NBs (DCP-NBs). 3D-image reconstruction of DCP-NBs shows that PML forms a shell around viral genomes and associated Daxx and ATRX, two PML partners within PML-NBs. During latency establishment (6 d.p.i.), infected mouse TGs display, at the level of the whole TG and in individual cells, a substantial increase of PML amount consistent with the interferon-mediated antiviral role of PML. "Single" and "Multiple" patterns are reminiscent of low and high-viral genome copy-containing neurons. We show that LAT expression is significantly favored within the "Multiple" pattern, which underlines a heterogeneity of LAT expression dependent on the viral genome copy number, pattern acquisition, and association with nuclear domains. Infection of PML-knockout mice demonstrates that PML/PML-NBs are involved in virus nuclear pattern acquisition, and negatively regulate the expression of the LAT. This study demonstrates that nuclear domains including PML-NBs and centromeres are functionally involved in the control of HSV-1 latency, and represent a key level of host/virus interaction

Cost-effectiveness of Universal Hepatitis C Virus Screening of Pregnant Women in the United States

BACKGROUND:Hepatitis C virus' (HCV) chronic prevalence among pregnant women in the United States doubled nationally from 2009-2014 (~0.7%), yet many cases remain undiagnosed. Screening pregnant women is not recommended by the Society of Maternal-Fetal Medicine or the Centers for Disease Control and Prevention, despite new American Association For the Study of Liver Diseases (AASLD)/Infectious Diseases Society of America (IDSA) guidelines recommending screening for this group. We assessed the cost-effectiveness of HCV screening for pregnant women in the United States. METHODS:An HCV natural history Markov model was used to evaluate the cost-effectiveness of universal HCV screening of pregnant women, followed by treatment after pregnancy, compared to background risk-based screening from a health-care payer perspective. We assumed a HCV chronic prevalence of 0.73% among pregnant women, based on national data. We assumed no Medicaid reimbursement restrictions by fibrosis stage at baseline, but explored differing restrictions in sensitivity analyses. We assessed costs (in US dollars) and health outcomes (in quality-adjusted life-years [QALYs]) over a lifetime horizon, using new HCV drug costs of $25 000/treatment. We assessed mean incremental cost-effectiveness ratios (ICERs) under a willingness-to-pay threshold of$50 000/QALY gained. We additionally evaluated the potential population impact. RESULTS:Universal antenatal screening was cost-effective in all treatment eligibility scenarios (mean ICER <$3000/QALY gained). Screening remained cost-effective at a prevalence of 0.07%, which is the lowest estimated prevalence in the United States (in Hawaii). Screening the ~5.04 million pregnant women in 2018 could result in the detection and treatment of 33 000 women, based on current fibrosis restrictions. CONCLUSIONS:Universal screening for HCV among pregnant women in the United States is cost-effective and should be recommended nationally

Réalité augmentée pour stimuler le commerce local

Créer une application en réalité augmentée pour le Rallye du Shopping de Crans- Montana, voici l’objectif principal de ce travail de Bachelor. Pour y parvenir, plusieurs étapes sont nécessaires. Dans un premier temps, afin de comprendre ce qu’est la réalité augmentée, une explication de celle-ci est donnée ainsi que ses différences avec la réalité virtuelle. Puis un bref résumé de son historique et les bases de son fonctionnement sont présentés. Il est aussi nécessaire de savoir quel est le contexte actuel du Rallye du Shopping ainsi que le déroulement des précédentes éditions. Pour pouvoir proposer une solution viable, les attentes et les contraintes doivent également être connues

Sémiotique et visualisation de l'identité numérique: une étude comparée de Facebook et Myspace

Digital identity is divided into 3 sign sets: (1) declarative identity, (2) acting identity and (3) calculated identity. This typology allows leading a quantitative analysis of cultural influence of identity representation in social web, through the comparative study of two social networks: Facebook and MySpace. Unlike early web, social web makes possible identification of a user without having to declare describing elements. The comparative analysis presented here continues this analysis by specifying the procedures of this new paradigm of identity and highlighting two different ideologies of identity, on the one hand, a normative one to stimulate socialization, on the other hand, an egocentric one for the sake of self-expression. “Calculated identity” encourages users to make comparisons between them and feed their representation, but increasing disproportionately the number of friends is not sufficient to play the social game as it is structured by Facebook: visualization shows that the social network is maintained by sharing. Sharing photos, participating in shared groups is a part of regular social interaction announcing the emergence of a new intersubjective language.Un modèle sémiotique de l'identité numérique construit précédemment distingue 3 ensembles de signes : l'identité déclarative, agissante et calculée. Ce modèle est utilisé pour développer une analyse quantitative appliquée de l'emprise culturelle du web 2.0 sur la représentation de l'identité à travers l'étude comparative de deux logiciels de réseaux sociaux, Facebook et Myspace. Contrairement au premier web, le web social rend possible l'identification personnelle d'un utilisateur sans qu'il ait à déclarer des éléments qui le décrivent ; l'analyse comparée ici présentée poursuit cette analyse en précisant les procédés de ce nouveau paradigme identitaire et mettant en évidence des idéologies identitaires différentes, l'une normative par souci de socialisation, l'autre égocentrée par souci d'expression de soi. L'identité calculée incite les utilisateurs à établir des comparaisons entre eux et à nourrir leur représentation, mais il ne s'agit pas pour autant de jouer à accroître démesurément un critère comme le nombre d'amis pour jouer le jeu social : les graphes nœud-lien montrent que le réseau s'entretient par le partage. Partager des photographies, participer à des groupes communs fait partie des échanges sociaux réguliers qui annoncent l'émergence d'un nouveau langage intersubjectif

Characterization of Canadian propolis fractions obtained from two-step sequential extraction

AbstractThe antioxidant capacity, as well as the concentration threshold for sensorial detection of Canadian propolis fractions in milk were determined. Propolis fractions were obtained using two-step sequential extraction with ethanol and water. Two processing pathways were carried out by interchanging ethanol and water extraction steps. Total polyphenol and flavonoid contents were quantified and ESI-MS fingerprints in negative mode were collected to determine the chemical composition of the propolis and propolis extracts. The ferric-reducing power assay and DPPH· methods were performed to determine antioxidant capacity. For both extraction pathways, the ethanolic extract showed higher polyphenol and flavonoid concentrations and higher antioxidant capacity as compared to commercial propolis and water extracts. The polyphenol composition of the extracts varied according to both, the extraction solvent and the extraction pathway as revealed by ESI-MS fingerprints. The sensory detection threshold concentration in milk was significantly higher in water extracts than in ethanol extracts. It was further increased when ethanol extraction was carried out as the first step and water extraction as the second step. The results of this study suggest that sequential extraction process can be used to produce propolis fractions with different polyphenol composition, antioxidant and sensory properties

Effectiveness of hand washing on the removal of iron oxide nanoparticles from human skin ex vivo.

In this study, the effectiveness of washing with soap and water in removing nanoparticles from exposed skin was investigated. Dry, nanoscale hematite (α-Fe javax.xml.bind.JAXBElement@3059c7bd O javax.xml.bind.JAXBElement@2ae40c27 ) or maghemite (γ-Fe javax.xml.bind.JAXBElement@1b3855ef O javax.xml.bind.JAXBElement@384459af ) powder, with primary particle diameters between 20-30 nm, were applied to two samples each of fresh and frozen ex vivo human skin in two independent experiments. The permeation of nanoparticles through skin, and the removal of nanoparticles after washing with soap and water were investigated. Bare iron oxide nanoparticles remained primarily on the surface of the skin, without penetrating beyond the stratum corneum. Skin exposed to iron oxide nanoparticles for 1 and 20 hr resulted in removal of 85% and 90%, respectively, of the original dose after washing. In the event of dermal exposure to chemicals, removal is essential to avoid potential local irritation or permeation across skin. Although manufactured at an industrial scale and used extensively in laboratory experiments, limited data are available on the removal of engineered nanoparticles after skin contact. Our finding raises questions about the potential consequences of nanoparticles remaining on the skin and whether alternative washing methods should be proposed. Further studies on skin decontamination beyond use of soap and water are needed to improve the understanding of the potential health consequences of dermal exposure to nanoparticles

A Review of Deep Learning Models for Twitter Sentiment Analysis: Challenges and Opportunities

Microblogging site Twitter (re-branded to X since July 2023) is one of the most influential online social media websites, which offers a platform for the masses to communicate, expresses their opinions, and shares information on a wide range of subjects and products, resulting in the creation of a large amount of unstructured data. This has attracted significant attention from researchers who seek to understand and analyze the sentiments contained within this massive user-generated text. The task of sentiment analysis (SA) entails extracting and identifying user opinions from the text, and various lexicon-and machine learning-based methods have been developed over the years to accomplish this. However, deep learning (DL)-based approaches have recently become dominant due to their superior performance. This study briefs on standard preprocessing techniques and various word embeddings for data preparation. It then delves into a taxonomy to provide a comprehensive summary of DL-based approaches. In addition, the work compiles popular benchmark datasets and highlights evaluation metrics employed for performance measures and the resources available in the public domain to aid SA tasks. Furthermore, the survey discusses domain-specific practical applications of SA tasks. Finally, the study concludes with various research challenges and outlines future outlooks for further investigation