10,921 research outputs found
Computer analysis of objects’ movement in image sequences: methods and applications
Computer analysis of objects’ movement in image sequences is a very complex problem, considering that it usually involves tasks for automatic detection, matching, tracking, motion analysis and deformation estimation. In spite of its complexity, this computational analysis has a wide range of
important applications; for instance, in surveillance systems, clinical analysis of human gait, objects recognition, pose estimation and deformation analysis.
Due to the extent of the purposes, several difficulties arise, such as the simultaneous tracking of manifold objects, their possible temporary occlusion or definitive disappearance from the image scene, changes of the viewpoints considered in images acquisition or of the illumination conditions, or even nonrigid deformations that objects may suffer in image sequences.
In this paper, we present an overview of several methods that may be considered to analyze objects’ movement; namely, for their segmentation, tracking and matching in images, and for estimation of the
deformation involved between images.This paper was partially done in the scope of project “Segmentation, Tracking and Motion Analysis of Deformable (2D/3D) Objects using Physical Principles”, with reference POSC/EEA-SRI/55386/2004,
financially supported by FCT -Fundação para a Ciência e a Tecnologia from Portugal. The fourth, fifth and seventh authors would like to thank also the support of their PhD grants from FCT with references SFRH/BD/29012/2006, SFRH/BD/28817/2006 and SFRH/BD/12834/2003, respectively
IRX-2, a Novel Immunotherapeutic, Enhances Functions of Human Dendritic Cells
Background: In a recent phase II clinical trial for HNSCC patients, IRX-2, a cell-derived biologic, promoted T-cell infiltration into the tumor and prolonged overall survival. Mechanisms responsible for these IRX-2-mediated effects are unknown. We hypothesized that IRX-2 enhanced tumor antigen-(TA)-specific immunity by up-regulating functions of dendritic cells (DC). Methodology/Principal Findings: Monocyte-derived DC obtained from 18 HNSCC patients and 12 healthy donors were matured using IRX-2 or a mix of TNF-α, IL-1β and IL-6 ("conv. mix"). Multicolor flow cytometry was used to study the DC phenotype and antigen processing machinery (APM) component expression. ELISPOT and cytotoxicity assays were used to evaluate tumor-reactive cytotoxic T lymphocytes (CTL). IL-12p70 and IL-10 production by DC was measured by Luminex® and DC migration toward CCL21 was tested in transwell migration assays. IRX-2-matured DC functions were compared with those of conv. mix-matured DC. IRX-2-matured DC expressed higher levels (p<0.05) of CD11c, CD40, CCR7 as well as LMP2, TAP1, TAP2 and tapasin than conv. mix-matured DC. IRX-2-matured DC migrated significantly better towards CCL21, produced more IL-12p70 and had a higher IL12p70/IL-10 ratio than conv. mix-matured DC (p<0.05 for all). IRX-2-matured DC carried a higher density of tumor antigen-derived peptides, and CTL primed with these DC mediated higher cytotoxicity against tumor targets (p<0.05) compared to the conv. mix-matured DC. Conclusion: Excellent ability of IRX-2 to induce ex vivo DC maturation in HNSCC patients explains, in part, its clinical benefits and emphasizes its utility in ex vivo maturation of DC generated for therapy. © 2013 Schilling et al
Accreting Black Holes
This chapter provides a general overview of the theory and observations of
black holes in the Universe and on their interpretation. We briefly review the
black hole classes, accretion disk models, spectral state classification, the
AGN classification, and the leading techniques for measuring black hole spins.
We also introduce quasi-periodic oscillations, the shadow of black holes, and
the observations and the theoretical models of jets.Comment: 41 pages, 18 figures. To appear in "Tutorial Guide to X-ray and
Gamma-ray Astronomy: Data Reduction and Analysis" (Ed. C. Bambi, Springer
Singapore, 2020). v3: fixed some typos and updated some parts. arXiv admin
note: substantial text overlap with arXiv:1711.1025
Observational constraints on the braneworld model with brane-bulk energy exchange
We investigate the viability of the braneworld model with energy exchange
between the brane and bulk, by using the most recent observational data related
to the background evolution. We show that this energy exchange behaves like a
source of dark energy and can alter the profile of the cosmic expansion. The
new Supernova Type Ia (SNIa) Gold sample, Supernova Legacy Survey (SNLS) data,
the position of the acoustic peak at the last scattering surface from the
Wilkinson Microwave Anisotropy Probe (WMAP) observations and the baryon
acoustic oscillation peak found in the Sloan Digital Sky Survey (SDSS) are used
to constrain the free parameters of this model. To infer its consistency with
the age of the Universe, we compare the age of old cosmological objects with
what computed using the best fit values for the model parameters. At 68% level
of confidence, the combination of Gold sample SNIa, Cosmic Microwave Background
(CMB) shift parameter and SDSS databases provide
, and
, hence a spatially flat Universe with
. The same combination with SNLS supernova
observation give ,
and consequently
provides a spatially flat Universe . These
results obviously seem to be compatible with the most recent WMAP results
indicating a flat Universe.Comment: 17 pages and 18 figures, V2: Added comments, references, explained
some topics related to the matter power spectrum as a robust constraint,
accepted for publication in Mon. Not. R. Astron. So
Genetic diversity of Brazilian isolates of feline immunodeficiency virus
We isolated Feline immunodeficiency virus (FIV) from three adult domestic cats, originating from two open shelters in Brazil. Viruses were isolated from PBMC following co-cultivation with the feline T-lymphoblastoid cell line MYA-1. All amplified env gene products were cloned directly into pGL8MYA. The nucleic acid sequences of seven clones were determined and then compared with those of previously described isolates. The sequences of all of the Brazilian virus clones were distinct and phylogenetic analysis revealed that all belong to subtype B. Three variants isolated from one cat and two variants were isolated from each of the two other cats, indicating that intrahost diversity has the potential to pose problems for the treatment and diagnosis of FIV infection
Predictors of linkage to care following community-based HIV counseling and testing in rural Kenya
Despite innovations in HIV counseling and testing (HCT), important gaps remain in understanding linkage to care. We followed a cohort diagnosed with HIV through a community-based HCT campaign that trained persons living with HIV/AIDS (PLHA) as navigators. Individual, interpersonal, and institutional predictors of linkage were assessed using survival analysis of self-reported time to enrollment. Of 483 persons consenting to follow-up, 305 (63.2%) enrolled in HIV care within 3 months. Proportions linking to care were similar across sexes, barring a sub-sample of men aged 18–25 years who were highly unlikely to enroll. Men were more likely to enroll if they had disclosed to their spouse, and women if they had disclosed to family. Women who anticipated violence or relationship breakup were less likely to link to care. Enrolment rates were significantly higher among participants receiving a PLHA visit, suggesting that a navigator approach may improve linkage from community-based HCT campaigns.Vestergaard Frandse
Worldwide trends in diabetes since 1980: a pooled analysis of 751 population-based studies with 4.4 million participants
Background: One of the global targets for non-communicable diseases is to halt, by 2025, the rise in the age-standardised adult prevalence of diabetes at its 2010 levels. We aimed to estimate worldwide trends in diabetes, how likely it is for countries to achieve the global target, and how changes in prevalence, together with population growth and ageing, are affecting the number of adults with diabetes. Methods: We pooled data from population-based studies that had collected data on diabetes through measurement of its biomarkers. We used a Bayesian hierarchical model to estimate trends in diabetes prevalence-defined as fasting plasma glucose of 7.0 mmol/L or higher, or history of diagnosis with diabetes, or use of insulin or oral hypoglycaemic drugs-in 200 countries and territories in 21 regions, by sex and from 1980 to 2014. We also calculated the posterior probability of meeting the global diabetes target if post-2000 trends continue. Findings: We used data from 751 studies including 4,372,000 adults from 146 of the 200 countries we make estimates for. Global age-standardised diabetes prevalence increased from 4.3% (95% credible interval 2.4-7.0) in 1980 to 9.0% (7.2-11.1) in 2014 in men, and from 5.0% (2.9-7.9) to 7.9% (6.4-9.7) in women. The number of adults with diabetes in the world increased from 108 million in 1980 to 422 million in 2014 (28.5% due to the rise in prevalence, 39.7% due to population growth and ageing, and 31.8% due to interaction of these two factors). Age-standardised adult diabetes prevalence in 2014 was lowest in northwestern Europe, and highest in Polynesia and Micronesia, at nearly 25%, followed by Melanesia and the Middle East and north Africa. Between 1980 and 2014 there was little change in age-standardised diabetes prevalence in adult women in continental western Europe, although crude prevalence rose because of ageing of the population. By contrast, age-standardised adult prevalence rose by 15 percentage points in men and women in Polynesia and Micronesia. In 2014, American Samoa had the highest national prevalence of diabetes (>30% in both sexes), with age-standardised adult prevalence also higher than 25% in some other islands in Polynesia and Micronesia. If post-2000 trends continue, the probability of meeting the global target of halting the rise in the prevalence of diabetes by 2025 at the 2010 level worldwide is lower than 1% for men and is 1% for women. Only nine countries for men and 29 countries for women, mostly in western Europe, have a 50% or higher probability of meeting the global target. Interpretation: Since 1980, age-standardised diabetes prevalence in adults has increased, or at best remained unchanged, in every country. Together with population growth and ageing, this rise has led to a near quadrupling of the number of adults with diabetes worldwide. The burden of diabetes, both in terms of prevalence and number of adults affected, has increased faster in low-income and middle-income countries than in high-income countries.Bin Zhou, Yuan Lu, Kaveh Hajifathalian, James Bentham … Robert J. Adams … Anne Taylor … et al. (WNCD Risk Factor Collaboration
Novel poly(L-lactic acid)/hyaluronic acid macroporous hybrid scaffolds : characterization and assessment of cytotoxicity
Poly(L-lactic acid), PLLA, a synthetic biodegradable polyester, is widely accepted in tissue engineering. Hyaluronic acid (HA), a natural polymer, exhibits an excellent biocompatibility, influences cell signaling, proliferation, and differentiation. In this study, HA crosslinking was performed by immersion of the polysaccharide in water-acetone mixtures containing glutaraldehyde (GA). The objective of this work is to produce PLLA scaffolds with the pores coated with HA, that could be beneficial for bone tissue engineering applications. PLLA tridimensional scaffolds were prepared by compression molding followed by salt leaching. After the scaffolds impregnation with soluble HA solutions of distinct concentration, a GA-crosslinking reaction followed by inactivation of the unreacted GA with glycine was carried out. An increase on surface roughness is shown by scanning electron microscopy (SEM) with the addition of HA. Toluidine blue staining indicates the present of stable crosslinked HA. An estimation of the HA original weight in the hybrid scaffolds was performed using thermal gravimetric analyses. FTIR-ATR and XPS confirmed the crosslinking reaction. Preliminary in vitro cell culture studies were carried out using a mouse lung fibroblast cell line (L929). SEM micrographs of L929 showed that cells adhered well, spread actively throughout all scaffolds, and grew favorably. A MTS test indicated that cells were viable when cultured onto the surface of all scaffolds, suggesting that the introduction of crosslinked HA did not increase the cytotoxicity of the hybrid scaffolds.Contract grant sponsor: Portuguese Foundation for Science and Technology (FCT) through POCTIContract grant sponsor: FEDER programs including project ProteoLight; contract grant number: PTDC/FIS/68517/2006Contract grant sponsor: European Union funded STREP Project HIPPOCRATES; contract grant number: NMP3-CT-2003-505758Contract grant sponsor: European NoE EXPERTISSUES; contract grant number: NMP3-CT-2004-500283Contract grant sponsor: Spanish Ministry of Science (The FEDER financial support); contract grant number: MAT2007-66759-C03-01The authors acknowledge the funding for research in the field of Regenerative Medicine through the collaboration agreement from the Conselleria de Sanidad (Generalitat Valenciana) and the Instituto de Salud Carlos III (Ministry of Science and Innovation). The European Union Financing, as part of the SOCRA-TES/Erasmus program is also gratefully acknowledged
Genomic, Pathway Network, and Immunologic Features Distinguishing Squamous Carcinomas
This integrated, multiplatform PanCancer Atlas study co-mapped and identified distinguishing
molecular features of squamous cell carcinomas (SCCs) from five sites associated with smokin
Pan-Cancer Analysis of lncRNA Regulation Supports Their Targeting of Cancer Genes in Each Tumor Context
Long noncoding RNAs (lncRNAs) are commonly dys-regulated in tumors, but only a handful are known toplay pathophysiological roles in cancer. We inferredlncRNAs that dysregulate cancer pathways, onco-genes, and tumor suppressors (cancer genes) bymodeling their effects on the activity of transcriptionfactors, RNA-binding proteins, and microRNAs in5,185 TCGA tumors and 1,019 ENCODE assays.Our predictions included hundreds of candidateonco- and tumor-suppressor lncRNAs (cancerlncRNAs) whose somatic alterations account for thedysregulation of dozens of cancer genes and path-ways in each of 14 tumor contexts. To demonstrateproof of concept, we showed that perturbations tar-geting OIP5-AS1 (an inferred tumor suppressor) andTUG1 and WT1-AS (inferred onco-lncRNAs) dysre-gulated cancer genes and altered proliferation ofbreast and gynecologic cancer cells. Our analysis in-dicates that, although most lncRNAs are dysregu-lated in a tumor-specific manner, some, includingOIP5-AS1, TUG1, NEAT1, MEG3, and TSIX, synergis-tically dysregulate cancer pathways in multiple tumorcontexts
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