713 research outputs found

    Trigeminal neuralgia

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    AbstractTwo different clinical entities, essential or secondary neuralgia, are associated with different pathologies. The pathways of CN V comprise the cervical spine, the brainstem, the root of the nerve and the three peripheral branches: V1, V2 and V3. The lesions responsible for neuralgia are neoplastic, vascular, inflammatory, malformative or post-traumatic. The examination protocol should explore the set of CN V pathways. Neurovascular compression is the main cause of essential neuralgia. It is investigated by T2-weighted inframillimetric volume. Two conditions are necessary to diagnose a neurovascular compression: localised on the root entry zone [(REZ), 2–6mm from the emergence of the pons] and perpendicularly. In the absence of neurovascular compression, thin slices and a gadolinium injection are necessary

    The role of surface roughness and slide-roll ratio in the decomposition of MoDTC in tribological contacts

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    In this study, the role of surface roughness and slide-roll ratio in the decomposition and friction performance of molybdenum dialkyldithiocarbamate (MoDTC) has been investigated. Tribotests were carried out in a MiniTraction Machine (MTM) using steel discs of varying roughness rubbing against smooth steel balls in a sliding/rolling contact. Tests were conducted at slide-roll ratio (SRR) values of SRR=100% and 200%. Raman spectroscopy was used to perform chemical characterisation on the resulting wear scars. The friction performance of rough discs was not affected by the slide-roll ratio. On the other hand, increasing the slide-roll ratio from 100% to 200% in tests with smooth discs resulted in higher friction with large instabilities. Raman analysis showed significant differences in chemical composition of the wear scars generated after tests with smooth and rough discs. Wear scars generated using rough discs were mainly composed of MoS2 indicating complete MoDTC decomposition while those generated using smooth discs were composed of a mixture of MoS2, MoSx (x>2) and FeMoO4 indicating partial MoDTC decomposition. Numerical simulation of the contact revealed that under similar loading conditions rough surfaces have higher local pressures than smoother surfaces. It is proposed that higher local pressures in rough surfaces promoted complete MoDTC decomposition. The novel finding from results presented in this study is that at similar temperature and MoDTC concentration, the degradation of MoDTC within tribocontacts is highly dependent on the roughness of the tribopair. This is because surface roughness determines the local pressure at the asperity asperity contact

    White matter microstructure of attentional networks predicts attention and consciousness functional interactions

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    Attention is considered as one of the pre-requisites of conscious perception. Phasic alerting and exogenous orienting improve conscious perception of near-threshold information through segregated brain networks. Using a multimodal neuroimaging approach, combining data from functional MRI (fMRI) and diffusion-weighted imaging (DWI), we investigated the influence of white matter properties of the ventral branch of superior longitudinal fasciculus (SLF III) in functional interactions between attentional systems and conscious perception. Results revealed that (1) reduced integrity of the left hemisphere SLF III was predictive of the neural interactions observed between exogenous orienting and conscious perception, and (2) increased integrity of the left hemisphere SLF III was predictive of the neural interactions observed between phasic alerting and conscious perception. Our results combining fMRI and DWI data demonstrate that structural properties of the white matter organization determine attentional modulations over conscious perception.ABC was supported by a Ramón y Cajal fellowship (RYC-2011-09320) and research project PSI2014-58681-P from the Spanish Ministry of Economy and Competitiveness (MINECO). PMP-A was supported by a Ramón y Cajal fellowship (RYC-2014-15440), and grants PSI2015-65696 and SEV-2015-049 from the MINECO. MTdS received funding from the ‘Agence Nationale de la Recherche’ (Grant number ANR-13-JSV4-0001-01) and “Investissements d’avenir” ANR-10-IAIHU-06. PB received funding from the ‘Agence Nationale de la Recherche’ (Grant number R16139DD)

    Integrating brain function and structure in the study of the human attentional networks: a functionnectome study

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    Published on 6 July 2024Attention is a heterogeneous function theoretically divided into different systems. While functional magnetic resonance imaging (fMRI) has extensively characterized their functioning, the role of white matter in cognitive function has gained recent interest due to diffusion-weighted imaging advancements. However, most evidence relies on correlations between white matter properties and behavioral or cognitive measures. This study used a new method that combines the signal from distant voxels of fMRI images using the probability of structural connection given by high-resolution normative tractography. We analyzed three fMRI datasets with a visual perceptual task and three attentional manipulations: phasic alerting, spatial orienting, and executive attention. The phasic alerting network engaged temporal areas and their communication with frontal and parietal regions, with left hemisphere dominance. The orienting network involved bilateral fronto-parietal and midline regions communicating by association tracts and interhemispheric fibers. The executive attention network engaged a broad set of brain regions and white matter tracts connecting them, with a particular involvement of frontal areas and their connections with the rest of the brain. These results partially confirm and extend previous knowledge on the neural substrates of the attentional system, offering a more comprehensive understanding through the integration of structure and function.M.M-S. is supported by a Margarita Salas fellowship by the Spanish Ministry of Universities and the European Next Generation funding, and by a contract for Young Researchers (PAIDI 20200) by the Ministry of Economy, Knowledge, Enterprise, and Universities of Andalusia. P.M.P-A. is supported by grants from the Spanish Ministry of Science and Innovation (PID2021-123574NB-I00), from the Basque Government (PIBA-2021-1-0003), from the Red guipuzcoana de Ciencia, Tecnología e Innovación of the Diputación Foral de Gipuzkoa (FA/OF 422/2022), from “la Caixa” Foundation (ID 100010434) under the agreement HR18-00178-DYSTHAL. BCBL acknowledges funding from the Basque Government through the BERC 2022–2025 program and by the Spanish State Research Agency through BCBL Severo Ochoa excellence accreditation CEX2020-001010-S. M.T.D.S is supported by the European Union’s Horizon 2020 research and innovation programme under the European Research Council (ERC) Consolidator grant agreement No. 818521 (M.T.d.S., DISCONNECTOME) M.T.D.S acknowledges funding from the University of Bordeaux’s IdEx ‘Investments for the Future’ program RRI ‘IMPACT’, which received financial support from the French government and IHU ‘Precision & Global Vascular Brain Health Institute – VBHI’ funded by the France 2030 initiative. A.B.C is supported by grants PSI2017-88136 and PID2020-119033 GB-I00 funded by MCIN/AEI/ https://doi.org/10.13039/501100011033, and by “ERDF A way of making Europe”, by the “European Union”; and by FEDER/Junta de Andalucía-Consejería de Economía y Conocimiento/ project A.SEJ.090. UGR18

    Model Kebijakan Penanggulangan Korupsi di Universitas Negeri YOGYAKARTA

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    Penelitian ini bertujuan untuk mengetahui kebijakan Universitas Negeri Yogyakarta dalam menanggulangi korupsi dan menemukan model kebijakan yang diinginkan Universitas Negeri Yogyakarta dalam menanggulangi korupsi. Penelitian ini adalah penelitian survei dengan pendekatan kuantitatif dan kualitatif. Sampel penelitian ditentukan secara multy stage sampling dengan teknik pengumpulan data dengan angket, dokumen dan diperkuat dengan pengumpulan data melalui Focus Group Discussion (FGD), dan validasi instrumen melalui validitas isi (content validity). Data dianalisis secara deskriptif. Hasil penelitian menunjukkan bahwa kebijakan penanggulangan korupsi di UNY tidak ada secara khusus dikeluarkan. Kebijakan yang ada mengikuti dan mempertahankan kebijakan yang lebih tinggi, yaitu dari Pemerintah. Model kebijakan penangggulangan korupsi di UNY yang digunakan adalah Model Rasional, yaitu kebijakan penanggulangan korupsi yang dikeluarkan merupakan aspirasi semua staf yang ada di unit kerja dan harus menekankan pada aspek efisiensi atas beban kerja pada unit kerja yang bersangkutan. Adapun kebijakan yang sudah ada yang berasal dari Pemerintah pusat dijadikan pedoman

    VSI: the VLTI spectro-imager

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    The VLTI Spectro Imager (VSI) was proposed as a second-generation instrument of the Very Large Telescope Interferometer providing the ESO community with spectrally-resolved, near-infrared images at angular resolutions down to 1.1 milliarcsecond and spectral resolutions up to R=12000. Targets as faint as K=13 will be imaged without requiring a brighter nearby reference object. The unique combination of high-dynamic-range imaging at high angular resolution and high spectral resolution enables a scientific program which serves a broad user community and at the same time provides the opportunity for breakthroughs in many areas of astrophysic including: probing the initial conditions for planet formation in the AU-scale environments of young stars; imaging convective cells and other phenomena on the surfaces of stars; mapping the chemical and physical environments of evolved stars, stellar remnants, and stellar winds; and disentangling the central regions of active galactic nuclei and supermassive black holes. VSI will provide these new capabilities using technologies which have been extensively tested in the past and VSI requires little in terms of new infrastructure on the VLTI. At the same time, VSI will be able to make maximum use of new infrastructure as it becomes available; for example, by combining 4, 6 and eventually 8 telescopes, enabling rapid imaging through the measurement of up to 28 visibilities in every wavelength channel within a few minutes. The current studies are focused on a 4-telescope version with an upgrade to a 6-telescope one. The instrument contains its own fringe tracker and tip-tilt control in order to reduce the constraints on the VLTI infrastructure and maximize the scientific return.Comment: 12 pages, to be published in Proc. SPIE conference 7013 "Optical and Infrared Interferometry", Schoeller, Danchi, and Delplancke, F. (eds.). See also http://vsi.obs.ujf-grenoble.f

    The Schro¨\ddot{o}dinger-Poisson equations as the large-N limit of the Newtonian N-body system: applications to the large scale dark matter dynamics

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    In this paper it is argued how the dynamics of the classical Newtonian N-body system can be described in terms of the Schro¨\ddot{o}dinger-Poisson equations in the large NN limit. This result is based on the stochastic quantization introduced by Nelson, and on the Calogero conjecture. According to the Calogero conjecture, the emerging effective Planck constant is computed in terms of the parameters of the N-body system as M5/3G1/2(N/)1/6\hbar \sim M^{5/3} G^{1/2} (N/)^{1/6}, where is GG the gravitational constant, NN and MM are the number and the mass of the bodies, and is their average density. The relevance of this result in the context of large scale structure formation is discussed. In particular, this finding gives a further argument in support of the validity of the Schro¨\ddot{o}dinger method as numerical double of the N-body simulations of dark matter dynamics at large cosmological scales.Comment: Accepted for publication in the Euro. Phys. J.

    Management of Myelodysplastic Syndrome Relapsing after Allogeneic Hematopoietic Stem Cell Transplantation: A Study by the French Society of Bone Marrow Transplantation and Cell Therapies

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    To find out prognostic factors and to investigate different therapeutic approaches, we report on 147 consecutive patients who relapsed after allogeneic hematopoietic stem cell transplantation (allo-HSCT) for myelodysplastic syndrome (MDS). Sixty-two patients underwent immunotherapy (IT group, second allo-HSCT or donor lymphocyte infusion), 39 received cytoreductive treatment alone (CRT group) and 46 were managed with palliative/supportive cares (PSC group). Two-year rates of overall survival (OS) were 32%, 6%, and 2% in the IT, CRT, and PSC groups, respectively (P < .001). In multivariate analysis, 4 factors adversely influenced 2-year rates of OS: history of acute graft-versus-host disease (hazard ratio [HR], 1.83; 95% confidence interval [CI], 1.26 to 2.67; P ¼ .002), relapse within 6 months (HR, 2.69; 95% CI, .82 to 3.98; P < .001), progression to acute myeloid leukemia (HR, 2.59; 95% CI, 1.75 to 3.83; P < .001), and platelet count < 50 G/L at relapse (HR, 1.68; 95% CI, 1.15 to 2.44; P ¼.007). A prognostic score based on those factors discriminated 2 risk groups with median OSs of 13.2 versus 2.4 months, respectively (P < .001). When propensity score, prognostic score, and treatment strategy were included in Cox model, immunotherapy was found to be an independent factor that favorably impacts OS (HR, .40; 95% CI, .26 to .63; P < .001). In conclusion, immunotherapy should be considered when possible for MDS patients relapsing after allo-HSCT
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