Artykuły w czasopismach: „Multimodal Posteriors”

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Speagle, Joshua S. "dynesty: a dynamic nested sampling package for estimating Bayesian posteriors and evidences". Monthly Notices of the Royal Astronomical Society 493, nr 3 (3.02.2020): 3132–58. http://dx.doi.org/10.1093/mnras/staa278.

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ABSTRACT We present dynesty, a public, open-source, python package to estimate Bayesian posteriors and evidences (marginal likelihoods) using the dynamic nested sampling methods developed by Higson et al. By adaptively allocating samples based on posterior structure, dynamic nested sampling has the benefits of Markov chain Monte Carlo (MCMC) algorithms that focus exclusively on posterior estimation while retaining nested sampling’s ability to estimate evidences and sample from complex, multimodal distributions. We provide an overview of nested sampling, its extension to dynamic nested sampling, the algorithmic challenges involved, and the various approaches taken to solve them in this and previous work. We then examine dynesty’s performance on a variety of toy problems along with several astronomical applications. We find in particular problems dynesty can provide substantial improvements in sampling efficiency compared to popular MCMC approaches in the astronomical literature. More detailed statistical results related to nested sampling are also included in the appendix.

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Campante, Tiago L., Tanda Li, J. M. Joel Ong, Enrico Corsaro, Margarida S. Cunha, Timothy R. Bedding, Diego Bossini i in. "Revisiting the Red Giant Branch Hosts KOI-3886 and ι Draconis. Detailed Asteroseismic Modeling and Consolidated Stellar Parameters". Astronomical Journal 165, nr 5 (27.04.2023): 214. http://dx.doi.org/10.3847/1538-3881/acc9c1.

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Abstract Asteroseismology is playing an increasingly important role in the characterization of red giant host stars and their planetary systems. Here, we conduct detailed asteroseismic modeling of the evolved red giant branch (RGB) hosts KOI-3886 and ι Draconis, making use of end-of-mission Kepler (KOI-3886) and multisector TESS (ι Draconis) time-series photometry. We also model the benchmark star KIC 8410637, a member of an eclipsing binary, thus providing a direct test to the seismic determination. We test the impact of adopting different sets of observed modes as seismic constraints. Inclusion of ℓ = 1 and 2 modes improves the precision of the stellar parameters, albeit marginally, compared to adopting radial modes alone, with 1.9%–3.0% (radius), 5%–9% (mass), and 19%–25% (age) reached when using all p-dominated modes as constraints. Given the very small spacing of adjacent dipole mixed modes in evolved RGB stars, the sparse set of observed g-dominated modes is not able to provide extra constraints, further leading to highly multimodal posteriors. Access to multiyear time-series photometry does not improve matters, with detailed modeling of evolved RGB stars based on (lower-resolution) TESS data sets attaining a precision commensurate with that based on end-of-mission Kepler data. Furthermore, we test the impact of varying the atmospheric boundary condition in our stellar models. We find the mass and radius estimates to be insensitive to the description of the near-surface layers, at the expense of substantially changing both the near-surface structure of the best-fitting models and the values of associated parameters like the initial helium abundance, Y i . Attempts to measure Y i from seismic modeling of red giants may thus be systematically dependent on the choice of atmospheric physics.

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Zhao, Yu, Pan Deng, Junting Liu, Xiaofeng Jia i Mulan Wang. "Causal Conditional Hidden Markov Model for Multimodal Traffic Prediction". Proceedings of the AAAI Conference on Artificial Intelligence 37, nr 4 (26.06.2023): 4929–36. http://dx.doi.org/10.1609/aaai.v37i4.25619.

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Multimodal traffic flow can reflect the health of the transportation system, and its prediction is crucial to urban traffic management. Recent works overemphasize spatio-temporal correlations of traffic flow, ignoring the physical concepts that lead to the generation of observations and their causal relationship. Spatio-temporal correlations are considered unstable under the influence of different conditions, and spurious correlations may exist in observations. In this paper, we analyze the physical concepts affecting the generation of multimode traffic flow from the perspective of the observation generation principle and propose a Causal Conditional Hidden Markov Model (CCHMM) to predict multimodal traffic flow. In the latent variables inference stage, a posterior network disentangles the causal representations of the concepts of interest from conditional information and observations, and a causal propagation module mines their causal relationship. In the data generation stage, a prior network samples the causal latent variables from the prior distribution and feeds them into the generator to generate multimodal traffic flow. We use a mutually supervised training method for the prior and posterior to enhance the identifiability of the model. Experiments on real-world datasets show that CCHMM can effectively disentangle causal representations of concepts of interest and identify causality, and accurately predict multimodal traffic flow.

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Posselt, Derek J., i Craig H. Bishop. "Nonlinear Parameter Estimation: Comparison of an Ensemble Kalman Smoother with a Markov Chain Monte Carlo Algorithm". Monthly Weather Review 140, nr 6 (1.06.2012): 1957–74. http://dx.doi.org/10.1175/mwr-d-11-00242.1.

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Abstract This paper explores the temporal evolution of cloud microphysical parameter uncertainty using an idealized 1D model of deep convection. Model parameter uncertainty is quantified using a Markov chain Monte Carlo (MCMC) algorithm. A new form of the ensemble transform Kalman smoother (ETKS) appropriate for the case where the number of ensemble members exceeds the number of observations is then used to obtain estimates of model uncertainty associated with variability in model physics parameters. Robustness of the parameter estimates and ensemble parameter distributions derived from ETKS is assessed via comparison with MCMC. Nonlinearity in the relationship between parameters and model output gives rise to a non-Gaussian posterior probability distribution for the parameters that exhibits skewness early and multimodality late in the simulation. The transition from unimodal to multimodal posterior probability density function (PDF) reflects the transition from convective to stratiform rainfall. ETKS-based estimates of the posterior mean are shown to be robust, as long as the posterior PDF has a single mode. Once multimodality manifests in the solution, the MCMC posterior parameter means and variances differ markedly from those from the ETKS. However, it is also shown that if the ETKS is given a multimode prior ensemble, multimodality is preserved in the ETKS posterior analysis. These results suggest that the primary limitation of the ETKS is not the inability to deal with multimodal, non-Gaussian priors. Rather it is the inability of the ETKS to represent posterior perturbations as nonlinear functions of prior perturbations that causes the most profound difference between MCMC posterior PDFs and ETKS posterior PDFs.

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Karkhaneh, Reza, Ahmad Masoumi, Nazanin Ebrahimiadib, Hormoz Chams i Mojtaba Abrishami. "Multimodal imaging in posterior microphthalmos". Journal of Current Ophthalmology 31, nr 3 (wrzesień 2019): 335–38. http://dx.doi.org/10.1016/j.joco.2019.01.001.

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Ba, Yuming, Jana de Wiljes, Dean S. Oliver i Sebastian Reich. "Randomized maximum likelihood based posterior sampling". Computational Geosciences 26, nr 1 (20.12.2021): 217–39. http://dx.doi.org/10.1007/s10596-021-10100-y.

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AbstractMinimization of a stochastic cost function is commonly used for approximate sampling in high-dimensional Bayesian inverse problems with Gaussian prior distributions and multimodal posterior distributions. The density of the samples generated by minimization is not the desired target density, unless the observation operator is linear, but the distribution of samples is useful as a proposal density for importance sampling or for Markov chain Monte Carlo methods. In this paper, we focus on applications to sampling from multimodal posterior distributions in high dimensions. We first show that sampling from multimodal distributions is improved by computing all critical points instead of only minimizers of the objective function. For applications to high-dimensional geoscience inverse problems, we demonstrate an efficient approximate weighting that uses a low-rank Gauss-Newton approximation of the determinant of the Jacobian. The method is applied to two toy problems with known posterior distributions and a Darcy flow problem with multiple modes in the posterior.

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Singh, Ramandeep, Uday Tekchandani, Bruttendu Moharana i Ankur Singh. "Multimodal imaging in a case of posterior microphthalmos". Indian Journal of Ophthalmology - Case Reports 1, nr 3 (2021): 422. http://dx.doi.org/10.4103/ijo.ijo_3474_20.

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Boulter, Daniel J., Marco Luigetti, Zoran Rumboldt, Julio A. Chalela i Alessandro Cianfoni. "Multimodal CT imaging of a posterior fossa stroke". Neurological Sciences 33, nr 1 (22.06.2011): 215–16. http://dx.doi.org/10.1007/s10072-011-0652-y.

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Forte, Raimondo, Florent Aptel, Audrey Feldmann i Christophe Chiquet. "MULTIMODAL IMAGING OF POSTERIOR POLAR ANNULAR CHOROIDAL DYSTROPHY". Retinal Cases & Brief Reports 12, nr 1 (2018): 29–32. http://dx.doi.org/10.1097/icb.0000000000000400.

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Gill, Jeff, i George Casella. "Dynamic Tempered Transitions for Exploring Multimodal Posterior Distributions". Political Analysis 12, nr 4 (2004): 425–43. http://dx.doi.org/10.1093/pan/mph027.

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Multimodal, high-dimension posterior distributions are well known to cause mixing problems for standard Markov chain Monte Carlo (MCMC) procedures; unfortunately such functional forms readily occur in empirical political science. This is a particularly important problem in applied Bayesian work because inferences are made from finite intervals of the Markov chain path. To address this issue, we develop and apply a new MCMC algorithm based on tempered transitions of simulated annealing, adding a dynamic element that allows the chain to self-tune its annealing schedule in response to current posterior features. This important feature prevents the Markov chain from getting trapped in minor modal areas for long periods of time. The algorithm is applied to a probabilistic spatial model of voting in which the objective function of interest is the candidate's expected return. We first show that such models can lead to complex target forms and then demonstrate that the dynamic algorithm easily handles even large problems of this kind.

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Salcedo Aparicio, Denisse Maricela, Karla Alexandra Ibarra Peña, Vestalia Isabel Ceballos Muñoz i Erick Stalin Pazmiño Peñafiel. "Significados digitales: comunicaciones multimodales y multialfabetizacion". RECIMUNDO 6, nr 3 (9.06.2022): 147–54. http://dx.doi.org/10.26820/recimundo/6.(3).junio.2022.147-154.

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El desarrollo de las TIC ha potenciado también un tipo de texto multimodal, donde la integración de los distintos modos (visual, sonoro, lingüístico, espacial y gestual) se dan amalgamados en la construcción del significado en un mismo texto. La metodología utilizada para el presente trabajo de investigación, se enmarcada dentro de una revisión bibliográfica de tipo documental, ya que nos vamos a ocupar de temas planteados a nivel teórico como es Significados digitales: comunicaciones multimodales y multialfabetizacion. La técnica para la recolección de datos está constituida por materiales electrónicos, estos últimos como Google Académico, entre otros, apoyándose para ello en el uso de descriptores certificados y avalados por el tesauro de la UNESCO. La información aquí obtenida será revisada para su posterior análisis. Hay una estrecha relación entre las comunicaciones multimodales y la multialfabetizacion, la primera por que implican una gran variedad de elementos que comunican y la segunda por que utilizan los primeros y los transforman gracias a las tecnologías de la comunicación e información en herramientas con capacidad de alfabetizar y generar conocimiento. La sociedad de conocimiento ha llegado para transformar la manera en que nos comunicamos y aprendemos, ya no es solo por medio de la escritura en cualquiera de sus formas, sino de una manera visual, musical y hasta táctil.

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Inan, Sibel, Elif Ertan i Umit Ubeyt Inan. "Multimodal imaging in a child with severe posterior scleritis". romanian journal of ophthalmology 63, nr 4 (20.12.2019): 397–402. http://dx.doi.org/10.22336/rjo.2019.64.

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Casalino, Giuseppe, Wing Chan, Clara McAvoy, Michele Coppola, Francesco Bandello, Alan C. Bird i Usha Chakravarthy. "Multimodal imaging of posterior ocular involvement in McArdle's disease". Clinical and Experimental Optometry 101, nr 3 (26.11.2017): 412–15. http://dx.doi.org/10.1111/cxo.12635.

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Plachti, Anna, Simon B. Eickhoff, Felix Hoffstaedter, Kaustubh R. Patil, Angela R. Laird, Peter T. Fox, Katrin Amunts i Sarah Genon. "Multimodal Parcellations and Extensive Behavioral Profiling Tackling the Hippocampus Gradient". Cerebral Cortex 29, nr 11 (4.02.2019): 4595–612. http://dx.doi.org/10.1093/cercor/bhy336.

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Abstract The hippocampus displays a complex organization and function that is perturbed in many neuropathologies. Histological work revealed a complex arrangement of subfields along the medial–lateral and the ventral–dorsal dimension, which contrasts with the anterior–posterior functional differentiation. The variety of maps has raised the need for an integrative multimodal view. We applied connectivity-based parcellation to 1) intrinsic connectivity 2) task-based connectivity, and 3) structural covariance, as complementary windows into structural and functional differentiation of the hippocampus. Strikingly, while functional properties (i.e., intrinsic and task-based) revealed similar partitions dominated by an anterior–posterior organization, structural covariance exhibited a hybrid pattern reflecting both functional and cytoarchitectonic subdivision. Capitalizing on the consistency of functional parcellations, we defined robust functional maps at different levels of partitions, which are openly available for the scientific community. Our functional maps demonstrated a head–body and tail partition, subdivided along the anterior–posterior and medial–lateral axis. Behavioral profiling of these fine partitions based on activation data indicated an emotion–cognition gradient along the anterior–posterior axis and additionally suggested a self-world-centric gradient supporting the role of the hippocampus in the construction of abstract representations for spatial navigation and episodic memory.

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Pujari, Amar, Shorya Vardhan Azad, Rachna Meel i Neiwete Lomi. "Bilateral retinocytoma: multimodal imaging assessment". BMJ Case Reports 11, nr 1 (grudzień 2018): e225908. http://dx.doi.org/10.1136/bcr-2018-225908.

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Clinical evaluation of an early-onset left esotropia in an adolescent revealed a large macular lesion with extensive posterior pole retinochoroidal atrophy from superior arcade to inferior arcade. The lesion also showed pigmentary changes over the base, edges and beyond, along with a popcorn-like calcification just above the inferior arcade. Swept-source optical CT (SS-OCT) confirmed extensive chorioretinal thinning with hyper-reflective foci corresponding to the calcification, and optical CT angiography revealed a disorganised superficial retinal plexus. Likewise, fundus screening of the other eye showed a well-defined fleshy mass lesion along the temporal retina in absence of any calcification. SS-OCT of the left eye lesion showed intraretinal mass with poorly defined retinal layers.

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Kompus, Kristiina, Tom Eichele, Kenneth Hugdahl i Lars Nyberg. "Multimodal Imaging of Incidental Retrieval: The Low Route to Memory". Journal of Cognitive Neuroscience 23, nr 4 (kwiecień 2011): 947–60. http://dx.doi.org/10.1162/jocn.2010.21494.

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Memories of past episodes frequently come to mind incidentally, without directed search. It has remained unclear how incidental retrieval processes are initiated in the brain. Here we used fMRI and ERP recordings to find brain activity that specifically correlates with incidental retrieval, as compared to intentional retrieval. Intentional retrieval was associated with increased activation in dorsolateral prefrontal cortex. By contrast, incidental retrieval was associated with a reduced fMRI signal in posterior brain regions, including extrastriate and parahippocampal cortex, and a modulation of a posterior ERP component 170 msec after the onset of visual retrieval cues. Successful retrieval under both intentional and incidental conditions was associated with increased activation in the hippocampus, precuneus, and ventrolateral prefrontal cortex, as well as increased amplitude of the P600 ERP component. These results demonstrate how early bottom–up signals from posterior cortex can lead to reactivation of episodic memories in the absence of strategic retrieval attempts.

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Thomas, Akshay S., i Phoebe Lin. "Multimodal imaging in infectious and noninfectious intermediate, posterior and panuveitis". Current Opinion in Ophthalmology 32, nr 3 (11.03.2021): 169–82. http://dx.doi.org/10.1097/icu.0000000000000762.

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Muñoz-Ramon, Pablo Vicente, Ana Isabel Fernández, Francisco José Muñoz Negrete i Baram Bodaghi. "Imagen multimodal en Epiteliopatía Pigmentosa Placoide Multifocal Posterior Aguda (APMPPE)". Revista de Investigación y Educación en Ciencias de la Salud (RIECS) 6, nr 2 (30.11.2021): 82–90. http://dx.doi.org/10.37536/riecs.2021.6.2.286.

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Presentamos el caso de un varón de 28 años que consultó por pérdida de visión bilateral en el que el examen de fondo de ojo mostró lesiones compatibles con una epiteliopatía placoide multifocal posterior aguda asociada a una inflamación granulomatosa aguda de la cámara anterior. El presente caso sirve para ilustrar el proceso diagnóstico por imagen multimodal a nivel oftalmológico y el despistaje de posibles enfermedades asociadas o síndromes mascarada a nivel sistémico. Asimismo, la presentación del caso se acompaña de una revisión bibliográfica sobre la epiteliopatía en placas.

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Filipovic, Marina, Eric Barat, Thomas Dautremer, Claude Comtat i Simon Stute. "PET Reconstruction of the Posterior Image Probability, Including Multimodal Images". IEEE Transactions on Medical Imaging 38, nr 7 (lipiec 2019): 1643–54. http://dx.doi.org/10.1109/tmi.2018.2886050.

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Paun, Luca, Alexandre Lavé, Gianpaolo Jannelli, Kristof Egervari, Insa Janssen, Karl Schaller, André O. von Bueren i Andrea Bartoli. "Pediatric Posterior Fossa ATRT: A Case Report, New Treatment Strategies and Perspectives". Brain Sciences 13, nr 5 (24.04.2023): 712. http://dx.doi.org/10.3390/brainsci13050712.

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Posterior fossa atypical teratoid rhabdoid tumor (ATRT) is a rare childhood tumor usually associated with a dismal prognosis. Although upfront surgical gross total resection (GTR) has classically been the first line of treatment, new multimodal treatments, including two-stage surgery, are showing promising results in terms of overall survival (OS) and complication rate. We present a case of a 9-month-old child treated with two-staged surgery and chemotherapy. When deemed risky, multimodal treatments, including staged surgeries, can be a safe alternative to reduce surgical mortality and morbidity. At 23 months old, the patient had normal global development and no major impact on quality of life. We, therefore, discuss the most recent advancements from a treatment perspective, including molecular targeting.

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Ochroch, Jason, Victor Qi, Ignacio Badiola, Taras Grosh, Lu Cai, Veena Graff, Charles Nelson, Craig Israelite i Nabil M. Elkassabany. "Analgesic efficacy of adding the IPACK block to a multimodal analgesia protocol for primary total knee arthroplasty". Regional Anesthesia & Pain Medicine 45, nr 10 (31.08.2020): 799–804. http://dx.doi.org/10.1136/rapm-2020-101558.

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Background and objectivesPeripheral nerve blocks have been integrated into most multimodal analgesia protocols for total knee arthroplasty (TKA). The adductor canal block (ACB) has gained popularity because of its quadriceps muscle sparing. Similarly, local anesthetic injection between the popliteal artery and the posterior capsule of the knee, IPACK block, has been described to provide analgesia to the posterior capsule of the knee with motor-sparing qualities. This prospective randomized controlled trial aimed to assess the analgesic efficacy of adding the IPACK block to our current multimodal analgesic regimen, including the ACB, in patients undergoing primary TKA.Methods119 patients were randomized to receive either an IPACK or a sham block in addition to multimodal analgesia and an ACB. We were set to assess pain in the back of the knee 6 hours after surgery. Other end points included quality of recovery after surgery, pain scores, opioid requirements, and functional measures.ResultsPatients who received the IPACK block had less pain in the back of the knee 6 hours after surgery when compared with the sham block: 21.7% vs 45.8%, p<0.01. There was marginal improvement in other pain measures in the first 24 hours after surgery. However, opioid requirements, quality of recovery and functional measures were similar between the two groups.ConclusionThe IPACK block reduced the incidence of posterior knee pain 6 hours postoperatively.

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Rachidi, Inès, Lorella Minotti, Guillaume Martin, Dominique Hoffmann, Julien Bastin, Olivier David i Philippe Kahane. "The Insula: A Stimulating Island of the Brain". Brain Sciences 11, nr 11 (19.11.2021): 1533. http://dx.doi.org/10.3390/brainsci11111533.

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Direct cortical stimulation (DCS) in epilepsy surgery patients has a long history of functional brain mapping and seizure triggering. Here, we review its findings when applied to the insula in order to map the insular functions, evaluate its local and distant connections, and trigger seizures. Clinical responses to insular DCS are frequent and diverse, showing a partial segregation with spatial overlap, including a posterior somatosensory, auditory, and vestibular part, a central olfactory-gustatory region, and an anterior visceral and cognitive-emotional portion. The study of cortico-cortical evoked potentials (CCEPs) has shown that the anterior (resp. posterior) insula has a higher connectivity rate with itself than with the posterior (resp. anterior) insula, and that both the anterior and posterior insula are closely connected, notably between the homologous insular subdivisions. All insular gyri show extensive and complex ipsilateral and contralateral extra-insular connections, more anteriorly for the anterior insula and more posteriorly for the posterior insula. As a rule, CCEPs propagate first and with a higher probability around the insular DCS site, then to the homologous region, and later to more distal regions with fast cortico-cortical axonal conduction delays. Seizures elicited by insular DCS have rarely been specifically studied, but their rate does not seem to differ from those of other DCS studies. They are mainly provoked from the insular seizure onset zone but can also be triggered by stimulating intra- and extra-insular early propagation zones. Overall, in line with the neuroimaging studies, insular DCS studies converge on the view that the insula is a multimodal functional hub with a fast propagation of information, whose organization helps understand where insular seizures start and how they propagate.

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Lobo, Simonne, Indu Govindraj i Anand Rajendran. "Atypical associations of retinitis pigmentosa: A case series". Indian Journal of Ophthalmology - Case Reports 3, nr 3 (2023): 739–42. http://dx.doi.org/10.4103/ijo.ijo_2973_22.

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Central visual acuity in retinitis pigmentosa (RP) can be compromised by posterior subcapsular cataract, cystoid macular edema, epiretinal membrane, and macular hole formation. However, features like posterior pole neovascularization, central serous chorioretinopathy (CSCR), and proliferative diabetic retinopathy (PDR) are rare in RP. We report three such cases of atypical associations of common retinal diseases in RP that were detected on multimodal imaging.

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Shi, Ying, Gregory Apker i Christopher A. Buneo. "Multimodal representation of limb endpoint position in the posterior parietal cortex". Journal of Neurophysiology 109, nr 8 (15.04.2013): 2097–107. http://dx.doi.org/10.1152/jn.00223.2012.

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Understanding the neural representation of limb position is important for comprehending the control of limb movements and the maintenance of body schema, as well as for the development of neuroprosthetic systems designed to replace lost limb function. Multiple subcortical and cortical areas contribute to this representation, but its multimodal basis has largely been ignored. Regarding the parietal cortex, previous results suggest that visual information about arm position is not strongly represented in area 5, although these results were obtained under conditions in which animals were not using their arms to interact with objects in their environment, which could have affected the relative weighting of relevant sensory signals. Here we examined the multimodal basis of limb position in the superior parietal lobule (SPL) as monkeys reached to and actively maintained their arm position at multiple locations in a frontal plane. On half of the trials both visual and nonvisual feedback of the endpoint of the arm were available, while on the other trials visual feedback was withheld. Many neurons were tuned to arm position, while a smaller number were modulated by the presence/absence of visual feedback. Visual modulation generally took the form of a decrease in both firing rate and variability with limb vision and was associated with more accurate decoding of position at the population level under these conditions. These findings support a multimodal representation of limb endpoint position in the SPL but suggest that visual signals are relatively weakly represented in this area, and only at the population level.

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Gupta, Yogita, Neiwete Lomi, Vinay S. Patil i Saumya Yadav. "Intralenticular metallic foreign body ‘locked-in’ the posterior capsule and the utility of multimodal imaging". BMJ Case Reports 14, nr 9 (wrzesień 2021): e244104. http://dx.doi.org/10.1136/bcr-2021-244104.

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Intraocular foreign bodies (FBs) are common ocular injuries reporting to the emergency services all over the world. The authors highlight the findings and surgical management of a case of intralenticular metallic FB following an injury while using chisel and hammer. The ocular path of the FB (2 mm) could be traced from a self-sealed corneal perforation, extending through the anterior capsule rupture, terminating at the posterior capsule, forming a posterior capsule tent with a part embedded in clear lens. Preoperative ultrasound biomicroscopy gave clues on posterior capsule integrity and the exact site of FB, and helped prognosticate and plan the surgical management of the case. The ‘locked-in’ FB was extracted after clear lens aspiration and posterior capsulorrhexis. The posterior capsule acted as a natural barrier between anterior and posterior segment, where the FB was found embedded.

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Weigel, Andreas P., Mark A. Liniger i Christof Appenzeller. "Seasonal Ensemble Forecasts: Are Recalibrated Single Models Better than Multimodels?" Monthly Weather Review 137, nr 4 (1.04.2009): 1460–79. http://dx.doi.org/10.1175/2008mwr2773.1.

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Abstract Multimodel ensemble combination (MMEC) has become an accepted technique to improve probabilistic forecasts from short- to long-range time scales. MMEC techniques typically widen ensemble spread, thus improving the dispersion characteristics and the reliability of the forecasts. This raises the question as to whether the same effect could be achieved in a potentially cheaper way by rescaling single model ensemble forecasts a posteriori such that they become reliable. In this study a climate conserving recalibration (CCR) technique is derived and compared with MMEC. With a simple stochastic toy model it is shown that both CCR and MMEC successfully improve forecast reliability. The difference between these two methods is that CCR conserves resolution but inevitably dilutes the potentially predictable signal while MMEC is in the ideal case able to fully retain the predictable signal and to improve resolution. Therefore, MMEC is conceptually to be preferred, particularly since the effect of CCR depends on the length of the data record and on distributional assumptions. In reality, however, multimodels consist only of a finite number of participating single models, and the model errors are often correlated. Under such conditions, and depending on the skill metric applied, CCR-corrected single models can on average have comparable skill as multimodel ensembles, particularly when the potential model predictability is low. Using seasonal near-surface temperature and precipitation forecasts of three models of the Development of a European Multimodel Ensemble System for Seasonal-to-Interannual Prediction (DEMETER) dataset, it is shown that the conclusions drawn from the toy-model experiments hold equally in a real multimodel ensemble prediction system. All in all, it is not possible to make a general statement on whether CCR or MMEC is the better method. Rather it seems that optimum forecasts can be obtained by a combination of both methods, but only if first MMEC and then CCR is applied. The opposite order—first CCR, then MMEC—is shown to be of only little effect, at least in the context of seasonal forecasts.

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Juárez Muas, Derlin. "Manejo multimodal de la eventración gigante". REVISTA HISPANOAMERICANA DE HERNIA 6, nr 1 (31.01.2018): 3. http://dx.doi.org/10.20960/rhh.57.

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Antecedentes: La eventración gigante es una patología que afecta la calidad de vida de los pacientes, con altos índices de morbimortalidad y recidiva. Una correcta planificación prequirúrgica mejora las condiciones para la cirugía. El uso de descargas musculares y doble malla aumenta la seguridad de la eventroplastia. Objetivo: Describir el manejo multimodal de las eventraciones gigantes. Diseño: Estudio retrospectivo.Material y métodos: Presentamos dos pacientes mujeres con eventraciones gigantes manejadas con toxina botulínica A, neumoperitoneo preoperatorio, separación anatómica de componentes (a una anterior y a otra posterior) y eventroplastia con doble malla. Resultados: A ambas pacientes se les infiltró toxina botulínica tipo A (100 UI). A los 15 días se les efectuó neumoperitoneo preoperatorio progresivo durante 20 días. Se les realizó resección de cicatriz previa (diéresis por planos) y apertura y tratamiento del saco y se creó plano retrorrectal. En una paciente se efectuó descarga del oblicuo externo a lo Albanese bilateral, y en la otra, descarga del músculo transverso bilateral. Se efectuó cierre de aponeurosis posterior, se colocó malla de polipropileno pesado retromuscular y se fijó al pubis-Cooper, EIAS y transmuscular. Se cerró aponeurosis anterior, se colocó una segunda malla preaponeurótica de polipropileno liviano macroporoso y se fijó con sutura absorbible. Se dejaron drenajes prefasciales. Síntesis por planos. Se colocó faja en quirófano. El tiempo quirúrgico promedio fue de 217 minutos. Tuvieron buena evolución posquirúrgica, con alta hospitalaria a las 96 h y retorno laboral a los 30 días. Seguimiento PO de 14 meses, sin complicaciones ni recidiva clínico-ecográfica.Conclusiones: El manejo multimodal de las eventraciones gigantes permite a los pacientes llegar en mejores condiciones quirúrgicas. La toxina botulínica, el neumoperitoneo preoperatorio y las descargas musculares aumentan el porcentaje de restitución de la línea media sin tensión, minimizando el riesgo de hipertensión intraabdominal posoperatoria. La colocación de doble malla aumenta la seguridad de la plástica y disminuye la recidiva en pacientes con defectos complejos de la pared abdominal.

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Silva Costa, Ramon. "O que procura? A digitalização do desejo e as performances de masculinidades no aplicativo GRINDR". CSOnline - REVISTA ELETRÔNICA DE CIÊNCIAS SOCIAIS, nr 32 (19.04.2021): 188–213. http://dx.doi.org/10.34019/1981-2140.2020.29262.

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O artigo aborda o processo de digitalização das relações homossexuais como parte dos efeitos dos avanços tecnológicos da contemporaneidade. Questiona: como os perfis do aplicativo Grindr em Juiz de Fora performam masculinidades? E quais masculinidades são essas? O objetivo é compreender como os usuários realizam performances acerca de suas masculinidades no ambiente digital. A metodologia empregada baseia-se em uma revisão bibliográfica, observação dos perfis e posterior análise de discurso multimodal em torno dos textos e fotos utilizadas por quatro usuários do aplicativo de relacionamento. Conclui-se que, as performances do aplicativo remontam performances existentes no meio sociocultural através dos recursos multimodais oferecidos pelo aplicativo. No entanto, os usuários apresentam uma pluralidade de representações do masculino, sendo um comportamento comum, a busca por parceiros com perfis semelhantes, a centralidade no corpo e sua estética e também a presença de perfis preocupados em manter em sigilo a orientação homossexual. Existem outros perfis que se descrevem e buscam por homens que não respondam ao estereotipo de comportamentos homossexuais e que exprimam uma masculinidade hegemônica, centrada na virilidade e heteronormatividade. Além disso, houve a análise de um perfil subversivo, que em seu texto contraria essas percepções trazidas pelos demais.

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Moshfeghi, DariusM, PeterA Karth, ChristianC Swinney i ArtisA Montague. "Multimodal imaging of posterior dislocation of crystalline lens nucleus following vitrectomy". Journal of Ophthalmic and Vision Research 10, nr 2 (2015): 197. http://dx.doi.org/10.4103/2008-322x.163785.

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Lee, Ho Jin, Il Sup Kim, Jae Hoon Sung, Sang Won Lee i Jae Taek Hong. "Significance of multimodal intraoperative monitoring for the posterior cervical spine surgery". Clinical Neurology and Neurosurgery 143 (kwiecień 2016): 9–14. http://dx.doi.org/10.1016/j.clineuro.2016.02.007.

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Glick-Shames, Haya, Tarek Keadan, Yael Backner, Atira Bick i Netta Levin. "Global Brain Involvement in Posterior Cortical Atrophy: Multimodal MR Imaging Investigation". Brain Topography 33, nr 5 (6.08.2020): 600–612. http://dx.doi.org/10.1007/s10548-020-00788-z.

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Tsui, Edmund, Orly Gal-Or, Quraish Ghadiali i K. Bailey Freund. "MULTIMODAL IMAGING ADDS NEW INSIGHTS INTO ACUTE SYPHILITIC POSTERIOR PLACOID CHORIORETINITIS". Retinal Cases & Brief Reports 12 (2018): S3—S8. http://dx.doi.org/10.1097/icb.0000000000000645.

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Stein, Klaus-Peter, Isabel Wanke, Marc Schlamann, Philipp Dammann, Alexia-Sabine Moldovan, Yuan Zhu, Ulrich Sure i I. Erol Sandalcioglu. "Posterior fossa arterio-venous malformations: current multimodal treatment strategies and results". Neurosurgical Review 37, nr 4 (9.05.2014): 619–28. http://dx.doi.org/10.1007/s10143-014-0551-9.

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Alafaleq, Munirah, Cristina Georgeon, Kate Grieve i Vincent M. Borderie. "Multimodal imaging of pre-Descemet corneal dystrophy". European Journal of Ophthalmology 30, nr 5 (12.07.2019): 908–16. http://dx.doi.org/10.1177/1120672119862505.

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Purpose: The aim of this study was to assess structural and histological changes associated with pre-Descemet corneal dystrophy with multimodal in vivo imaging. Methods: Retrospective case series including eight corneas from four unrelated male patients with pre-Descemet corneal dystrophy characterized by the presence of punctiform gray opacities located just anterior to the Descemet membrane at slit-lamp examination of both eyes. In vivo confocal microscopy images were obtained in the central, paracentral, and peripheral corneal zones from the superficial epithelial cell layer down to the corneal endothelium in both eyes. Spectral domain optical coherence tomography scans (central and limbal zones) and mapping of both corneas were acquired. Results: Diffuse small extracellular stromal deposits, presence of enlarged hyperreflective keratocytes in the posterior stroma with either hyperreflective or hyporeflective intracellular dots, and presence of activated keratocytes in the very anterior stroma were observed in all corneas with in vivo confocal microscopy. Spectral domain optical coherence tomography scans showed a hyperreflective line anterior to Descemet’s membrane running from limbus to limbus and associated with a second thinner hyperreflective line just beneath Bowman’s layer. Fine hyperreflective particles were observed in the posterior, mid, and anterior stroma on optical coherence tomography scans. Conclusion: The clinical presentation and structural anomalies found in isolated sporadic pre-Descemet corneal dystrophy are in favor of a degenerative process affecting corneal keratocytes with no epithelial or endothelial involvement. The maximum damage is found just anterior to the Descemet membrane resulting in pre-Descemet membrane location of stromal opacities. Multimodal imaging of cornea reveals that the disorder affects the whole stroma and it permits better understanding of pre-Descemet corneal dystrophy pathophysiology together with ascertained diagnosis.

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Zhi-Xuan, Tan, Harold Soh i Desmond Ong. "Factorized Inference in Deep Markov Models for Incomplete Multimodal Time Series". Proceedings of the AAAI Conference on Artificial Intelligence 34, nr 06 (3.04.2020): 10334–41. http://dx.doi.org/10.1609/aaai.v34i06.6597.

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Integrating deep learning with latent state space models has the potential to yield temporal models that are powerful, yet tractable and interpretable. Unfortunately, current models are not designed to handle missing data or multiple data modalities, which are both prevalent in real-world data. In this work, we introduce a factorized inference method for Multimodal Deep Markov Models (MDMMs), allowing us to filter and smooth in the presence of missing data, while also performing uncertainty-aware multimodal fusion. We derive this method by factorizing the posterior p(z|x) for non-linear state space models, and develop a variational backward-forward algorithm for inference. Because our method handles incompleteness over both time and modalities, it is capable of interpolation, extrapolation, conditional generation, label prediction, and weakly supervised learning of multimodal time series. We demonstrate these capabilities on both synthetic and real-world multimodal data under high levels of data deletion. Our method performs well even with more than 50% missing data, and outperforms existing deep approaches to inference in latent time series.

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Shah, Sagar A., Richard Guidry, Abhishek Kumar, Tyler White, Andrew King i Michael J. Heffernan. "Current Trends in Pediatric Spine Deformity Surgery: Multimodal Pain Management and Rapid Recovery". Global Spine Journal 10, nr 3 (22.09.2019): 346–52. http://dx.doi.org/10.1177/2192568219858308.

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Study Design: Narrative review. Objectives: The purpose of this article is to perform a review of the literature assessing the efficacy of opioid alternatives, multimodal pain regimens, and rapid recovery in pediatric spine surgery. Methods: A literature search utilizing PubMed database was performed. Relevant studies from all the evidence levels have been included. Recommendations to decrease postoperative pain and expedite recovery after posterior spinal fusion in adolescent idiopathic scoliosis patients have been provided based on results of studies with the highest level of evidence. Results: Refining perioperative pain management to lessen opioid consumption with multimodal regimens may be useful to decrease recovery time, pain, and complications. Nonsteroidal anti-inflammatory drugs, acetaminophen, gabapentin, neuraxial blockades, and local anesthesia alone offer benefits for postoperative pain management, but their combination in multimodal regimens and rapid recovery pathways may contribute to faster recovery time, improved pain levels, and lower reduction in total opioid consumption. Conclusion: A rapid recovery pathway using the multimodal approach for pediatric scoliosis correction may offer superior postoperative pain management and faster recovery than traditional opioid only pain protocols.

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Brixel, Sophia Margareta, Philippe Biboulet, Fabien Swisser, Olivier Choquet, Yassir Aarab, Helen Nguyen, Sophie Bringuier i Xavier Capdevila. "Posterior Quadratus Lumborum Block in Total Hip Arthroplasty: A Randomized Controlled Trial". Anesthesiology 134, nr 5 (19.03.2021): 722–33. http://dx.doi.org/10.1097/aln.0000000000003745.

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Background Pain management is important for ensuring early mobilization after hip arthroplasty; however, the optimal components remain controversial. Recently, the quadratus lumborum block has been proposed as an analgesic option. The current study tested the hypothesis that the posterior quadratus lumborum block combined with multimodal analgesia decreases morphine consumption after hip arthroplasty. Methods This study was a prospective, randomized, double-blind, placebo-controlled trial. Before general anesthesia, 100 participating patients scheduled for elective total hip arthroplasty were randomly allocated to receive a 30-ml injection posterior to the quadratus lumborum muscle with either 0.33% ropivacaine (n = 50) or normal saline (n = 50). For all patients, multimodal analgesia included systematic administration of acetaminophen, ketoprofen, and a morphine intravenous patient-controlled analgesia. The primary outcome was total intravenous morphine consumption in the first 24 h. Secondary outcomes recorded intraoperative sufentanil consumption; morphine consumption in the postanesthesia care unit; pain scores at extubation and at 2, 6, 12, and 24 h; motor blockade; time to first standing and ambulation; hospital length of stay; and adverse events. Results There was no significant difference in the 24-h total morphine consumption (ropivacaine group, median [interquartile range], 13 [7 to 21] versus saline group, 16 [9 to 21] mg; median difference, −1.5; 95% CI, −5 to 2; P = 0.337). Pain scores were not different between the groups (β = −0.4; 95% CI, −0.9 to 0.2; P = 0.199). There was no statistical difference between the two groups in intraoperative sufentanil consumption, morphine consumption in the postanesthesia care unit, motor blockade, times to first standing (median difference, 0.83 h; 95% CI, −1.7 to 3.4; P = 0.690) and ambulation (median difference, −1.85 h; 95% CI, −4.5 to 0.8; P = 0.173), hospital length of stay, and adverse events. Conclusions After elective hip arthroplasty, neither morphine consumption nor pain scores were reduced by the addition of a posterior quadratus lumborum block to a multimodal analgesia regimen. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

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Sugiura, Motoaki, Yuko Sassa, Jobu Watanabe, Yuko Akitsuki, Yasuhiro Maeda, Yoshihiko Matsue i Ryuta Kawashima. "Anatomical Segregation of Representations of Personally Familiar and Famous People in the Temporal and Parietal Cortices". Journal of Cognitive Neuroscience 21, nr 10 (październik 2009): 1855–68. http://dx.doi.org/10.1162/jocn.2008.21150.

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Person recognition has been assumed to entail many types of person-specific cognitive responses, including retrieval of knowledge, episodic recollection, and emotional responses. To demonstrate the cortical correlates of this modular structure of multimodal person representation, we investigated neural responses preferential to personally familiar people and responses dependent on familiarity with famous people in the temporal and parietal cortices. During functional magnetic resonance imaging (fMRI) measurements, normal subjects recognized personally familiar names (personal) or famous names with high or low degrees of familiarity (high or low, respectively). Effects of familiarity with famous people (i.e., high–low) were identified in the bilateral angular gyri, the left supramarginal gyrus, the middle part of the bilateral posterior cingulate cortices, and the left precuneus. Activation preferentially relevant to personally familiar people (i.e., personal–high) was identified in the bilateral temporo-parietal junctions, the right anterolateral temporal cortices, posterior middle temporal gyrus, posterior cingulate cortex (with a peak in the posterodorsal part), and the left precuneus; these activation foci exhibited varying degrees of activation for high and low names. An equivalent extent of activation was observed for all familiar names in the bilateral temporal poles, the left orbito-insular junction, the middle temporal gyrus, and the anterior part of the posterior cingulate cortex. The results demonstrated that distinct cortical areas supported different types of cognitive responses, induced to different degrees during recognition of famous and personally familiar people, providing neuroscientific evidence for the modularity of multimodal person representation.

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Cavallero, Edoardo, Vittorio Pirani, Claudia Cesari, Giulia Carrozzi, Alfonso Giovannini i Cesare Mariotti. "Multimodal Imaging Analysis of Acute Syphilitic Posterior Placoid Chorioretinitis: A Case Report". Ophthalmic Surgery, Lasers and Imaging Retina 50, nr 6 (1.06.2019): e179-e184. http://dx.doi.org/10.3928/23258160-20190605-13.

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Andersen, Richard A. "Multimodal integration for the representation of space in the posterior parietal cortex". Philosophical Transactions of the Royal Society of London. Series B: Biological Sciences 352, nr 1360 (29.10.1997): 1421–28. http://dx.doi.org/10.1098/rstb.1997.0128.

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The posterior parietal cortex has long been considered an ‘association’ area that combines information from different sensory modalities to form a cognitive representation of space. However, until recently little has been known about the neural mechanisms responsible for this important cognitive process. Recent experiments from the author's laboratory indicate that visual, somatosensory, auditory and vestibular signals are combined in areas LIP and 7a of the posterior parietal cortex.The integration of these signals can represent the locations of stimuli with respect to the observer and within the environment. Area MSTd combines visual motion signals, similar to those generated during an observer's movement through the environment, with eye–movement and vestibular signals. This integration appears to play a role in specifying the path on which the observer is moving. All three cortical areas combine different modalities into common spatial frames by using a gain–field mechanism. The spatial representations in areas LIP and 7a appear to be important for specifying the locations of targets for actions such as eye movements or reaching; the spatial representation within area MSTd appears to be important for navigation and the perceptual stability of motion signals.

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Lawley, Andrew Robert, Shouvik Saha i Francesco Manfredonia. "Posterior interosseous neuropathy: the diagnostic benefits of a multimodal approach to investigation". Clinical Case Reports 4, nr 4 (17.03.2016): 437–41. http://dx.doi.org/10.1002/ccr3.544.

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Stark, Andreas M., Ivo Leuschner, H. Maximilian Mehdorn i Alexander Claviez. "Ewing Sarcoma of the Posterior Fossa in an Adolescent Girl". Case Reports in Medicine 2014 (2014): 1–4. http://dx.doi.org/10.1155/2014/439830.

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Medulloblastoma, astrocytoma, and ependymoma represent the most common infratentorial tumors in childhood, while Ewing sarcomas in that localization are extremely rare. A large left infratentorial space-occupying lesion was diagnosed in a 12-year-old girl with signs of increased intracranial pressure. Following total tumor resection, histological and molecular examination revealed Ewing sarcoma with rearrangedEWSR-1gene. The patient achieved complete remission following adjuvant chemotherapy and radiotherapy according to Euro-EWING 2008 treatment protocol. Intracranial Ewing sarcoma, although rare, should be an important differential diagnosis of intracranial tumors in childhood which requires aggressive multimodal treatment.

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Tees, R. "The effects of posterior parietal and posterior temporal cortical lesions on multimodal spatial and nonspatial competencies in rats". Behavioural Brain Research 106, nr 1-2 (grudzień 1999): 55–73. http://dx.doi.org/10.1016/s0166-4328(99)00092-3.

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Befigiannis, G. N., E. N. Demiris i S. D. Likothanassis. "Evolutionary Nonlinear Multimodel Partitioning Filters". Journal of Advanced Computational Intelligence and Intelligent Informatics 5, nr 1 (20.01.2001): 8–14. http://dx.doi.org/10.20965/jaciii.2001.p0008.

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The problem of designing adaptive filters for nonlinear systems is faced in this work. The proposed evolution program combines the effectiveness of multimodel adaptive filters and the robustness of genetic algorithms (GAs). Specifically, a bank of different extended Kalman filters is implemented. Then, the a posteriori probability that a specific model of the bank of conditional models is the true one can be used as a GA fitness function. The superiority of the algorithm is that it evolves concurrently the models’ population with initial conditions. Thus, this procedure alleviates extended Kalman filter sensitivity in initial conditions, by estimating the best values. In addition to this, adaptive implementation is proposed that relieves the disadvantage of time-consuming GA implementation. Finally, a variety of defined crossover and mutation operators is investigated in order to accelerate the algorithm’s convergence.

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Li, Xin, i Albert C. Reynolds. "A Gaussian Mixture Model as a Proposal Distribution for Efficient Markov-Chain Monte Carlo Characterization of Uncertainty in Reservoir Description and Forecasting". SPE Journal 25, nr 01 (23.09.2019): 001–36. http://dx.doi.org/10.2118/182684-pa.

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Summary Generating an estimate of uncertainty in production forecasts has become nearly standard in the oil industry, but is often performed with procedures that yield at best a highly approximate uncertainty quantification. Formally, the uncertainty quantification of a production forecast can be achieved by generating a correct characterization of the posterior probability-density function (PDF) of reservoir-model parameters conditional to dynamic data and then sampling this PDF correctly. Although Markov-chain Monte Carlo (MCMC) provides a theoretically rigorous method for sampling any target PDF that is known up to a normalizing constant, in reservoir-engineering applications, researchers have found that it might require extraordinarily long chains containing millions to hundreds of millions of states to obtain a correct characterization of the target PDF. When the target PDF has a single mode or has multiple modes concentrated in a small region, it might be possible to implement a proposal distribution dependent on a random walk so that the resulting MCMC algorithm derived from the Metropolis-Hastings acceptance probability can yield a good characterization of the posterior PDF with a computationally feasible chain length. However, for a high-dimensional multimodal PDF with modes separated by large regions of low or zero probability, characterizing the PDF with MCMC using a random walk is not computationally feasible. Although methods such as population MCMC exist for characterizing a multimodal PDF, their computational cost generally makes the application of these algorithms far too costly for field application. In this paper, we design a new proposal distribution using a Gaussian mixture PDF for use in MCMC where the posterior PDF can be multimodal with the modes spread far apart. Simply put, the method generates modes using a gradient-based optimization method and constructs a Gaussian mixture model (GMM) to use as the basic proposal distribution. Tests on three simple problems are presented to establish the validity of the method. The performance of the new MCMC algorithm is compared with that of random-walk MCMC and is also compared with that of population MCMC for a target PDF that is multimodal.

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Dovranić, Josipa, Matija Bagarić, Marija Karača, Vladimir Trkulja i Danijel Matek. "Standard Multimodal Postoperative Analgesia Might Not Be Equally Effective When Comparing Anterior and Posterior Spondylodesis". Croatian nursing journal 4, nr 1 (16.06.2020): 81–89. http://dx.doi.org/10.24141/2/4/1/7.

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Introduction. Surgical treatment of structural adolescent scoliosis, either through anterior or posterior spinal fusion, results in severe pain. Aim. In comparison with the anterior approach, the posterior approach is considered advantageous in that several spine curvatures can be corrected in a single operative act. The aim was to compare the effectiveness of a morphine-based multimodal protocol over the first 48 postoperative hours in anterior and posterior surgeries. Methods. This retrospective chart review included consecutive adolescents (10-21 years of age) treated using either the anterior (n=28) or the posterior (n=30) approach at a single hospital centre over 3 years (2015-2017). Intravenous morphine (48 mg/24 hours) was administered at hourly intervals; pain was assessed using an 11-point (higher score=worse pain) visual analogue scale on 12 occasions during the first 24 hours and on 3 occasions during the second 24 hours. Additional analgesia (non-opioid or weak opioid) was delivered on demand and/or according to medical assessment. Results. With adjustments for age and number of affected spinal segments, VAS pain scores were lower in the anterior approach, overall (48 hours) (difference = -18%, 95% CI -30 to -5), and particularly over hours 0-3 (-23%, 95% CI -36 to -7%) and hours 4-6 (-26%, 95% CI -40 to -10%) after the surgery. The rate of additional analgesic administrations was comparable throughout the observed period (rate ratios around 1.0). Conclusion. The evaluated intravenous morphinebased multimodal analgesic protocol appeared less effective in surgeries using the posterior approach, suggesting that the two approaches might require different protocols for the same level of analgesia.

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Barceló, Francisco, José A. Periáñez i Antoni Gomila. "Tidying up sensory stores with supraordinate representations". Behavioral and Brain Sciences 26, nr 6 (grudzień 2003): 730–31. http://dx.doi.org/10.1017/s0140525x03240164.

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In attempting to integrate the authors' proposed model with results from analogous human event-related potential (ERP) research, we found difficulties with: (1) its apparent disregard for supraordinate representations at posterior multimodal association cortices, (2) its failure to address contextual task effects, and (3) its strict architectural dichotomy between memory storage and control functions.

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Hwang, Inae, i Marta Ugarte. "Morning glory disc anomaly-associated maculopathy: multimodal imaging". BMJ Case Reports 14, nr 1 (styczeń 2021): e237462. http://dx.doi.org/10.1136/bcr-2020-237462.

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Morning glory disc anomaly (MGDA) is most commonly found in white females in childhood with reduced vision. One in two cases have been reported to develop maculopathy or posterior pole retinal detachment as they grow older. The pathophysiology of MGDA-associated maculopathy is not well understood.We describe a 31-year-old black woman, who presented with gradual reduction of vision in the right eye due to MGDA-associated maculopathy. We identified morphological characteristics of the optic disc and macula with multicolour and optical coherence tomography imaging.We speculate that the centripetal inner retina traction and cerebrospinal fluid pressure fluctuation play an important role in inner retinal fluid accumulation in the pathology of retinoschisis in MGDA. Further studies will shed some light of a potential cause-and-effect relationship between MGDA and retinoschisis.

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Stanski, Carin, Cynthia Fernandes Pinto Luz, Adriana Ribeiro Ferreira Rodrigues i Melissa Koch Fernandes de Souza Nogueira. "Ensino de Botânica no Ensino Fundamental: estudando o pólen por meio de multimodos". Hoehnea 43, nr 1 (marzec 2016): 19–26. http://dx.doi.org/10.1590/2236-8906-34/2015.

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RESUMO O presente estudo teve como objetivo investigar o uso de multimodos de representação como estratégia didática para facilitar a aprendizagem significativa de alunos da sétima série do Ensino Fundamental referente ao tema pólen, utilizando mapas conceituais como avaliação. Os alunos elaboraram mapas conceituais à priori e à posteriori as aulas com multimodos de representação. Verificamos que os multimodos de representação propiciam uma aprendizagem significativa sobre conteúdos de botânica e que os mapas conceituais podem ser utilizados como avaliação.

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El mokhtari, Karim, Serge Reboul, Georges Stienne, Jean Bernard Choquel, Benaissa Amami i Mohammed Benjelloun. "An IMM Filter Defined in the Linear-Circular Domain, Application to Maneuver Detection with Heading Only". Mathematical Problems in Engineering 2018 (6.11.2018): 1–14. http://dx.doi.org/10.1155/2018/3531075.

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In this article, we propose a multimodel filter for circular data. The so-called Circular Interacting Multimodel filter is derived in a Bayesian framework with the circular normal von Mises distribution. The aim of the proposed filter is to obtain the same performance in the circular domain as the classical IMM filter in the linear domain. In our approach, the mixing and fusion stages of the Circular Interacting Multimodel filter are, respectively, defined from the a priori and from the a posteriori circular distributions of the state angle knowing the measurements and according to a set of models. We propose in this article a set of circular models that will be used in order to detect the vehicle maneuvers from heading measurements. The Circular Interacting Multimodel filter performances are assessed on synthetic data and we show on real data a vehicle maneuver detection application.

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