115 research outputs found

    Radiomic Analysis Reveals Prognostic Information in T1-Weighted Baseline Magnetic Resonance Imaging in Patients With Glioblastoma

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    Objectives The aim of this study was to investigate whether radiomic analysis with random survival forests (RSFs) can predict overall survival from T1-weighted contrast-enhanced baseline magnetic resonance imaging (MRI) scans in a cohort of glioblastoma multiforme (GBM) patients with uniform treatment. Materials and Methods This retrospective study was approved by the institutional review board and informed consent was waived. The MRI scans from 66 patients with newly diagnosed GBM from a previous prospective study were analyzed. Tumors were segmented manually on contrast-enhanced 3-dimensional T1-weighted images. Using these segmentations, P = 208 quantitative image features characterizing tumor shape, signal intensity, and texture were calculated in an automated fashion. On this data set, an RSF was trained using 10-fold cross validation to establish a link between image features and overall survival, and the individual risk for each patient was predicted. The mean concordance index was assessed as a measure of prediction accuracy. Association of individual risk with overall survival was assessed using Kaplan-Meier analysis and a univariate proportional hazards model. Results Mean overall survival was 14 months (range, 0.8-85 months). Mean concordance index of the 10-fold cross-validated RSF was 0.67. Kaplan-Meier analysis clearly distinguished 2 patient groups with high and low predicted individual risk (P = 5.5 x 10(-5)). Low predicted individual mortality was found to be a favorable prognostic factor for overall survival in a univariate Cox proportional hazards model (hazards ratio, 1.038;95% confidence interval, 1.015-1.062;P = 0.0059). Conclusions This study demonstrates that baseline MRI in GBM patients contains prognostic information, which can be accessed by radiomic analysis using RSFs

    Observation of strong final-state effects in pi+ production in pp collisions at 400 MeV

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    Differential cross sections of the reactions pp→dπ+pp \to d\pi^+ and pp→pnπ+pp \to pn\pi^+ have been measured at Tp=400T_p = 400 MeV by detecting the charged ejectiles in the angular range 40≀ΘLab≀21∘4^0 \leq \Theta_{Lab} \leq 21^\circ. The deduced total cross sections agree well with those published previously for neighbouring energies. The invariant mass spectra are observed to be strongly affected by Δ\Delta production and NNNN final-state interaction. The data are well described by Monte Carlo simulations including both these effects. The ratio of pp→pnπ+pp \to pn\pi^+ and pp→dπ+pp \to d\pi^+ cross sections also compares favourably to a recent theoretical prediction which suggests a dominance of npnp-production in the relative 3S1^3S_1-state.Comment: 17 pages, 5 figure

    Direct image to subtype prediction for brain tumors using deep learning

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    BACKGROUND: Deep Learning (DL) can predict molecular alterations of solid tumors directly from routine histopathology slides. Since the 2021 update of the World Health Organization (WHO) diagnostic criteria, the classification of brain tumors integrates both histopathological and molecular information. We hypothesize that DL can predict molecular alterations as well as WHO subtyping of brain tumors from hematoxylin and eosin-stained histopathology slides. METHODS: We used weakly supervised DL and applied it to three large cohorts of brain tumor samples, comprising N = 2845 patients. RESULTS: We found that the key molecular alterations for subtyping, IDH and ATRX, as well as 1p19q codeletion, were predictable from histology with an area under the receiver operating characteristic curve (AUROC) of 0.95, 0.90, and 0.80 in the training cohort, respectively. These findings were upheld in external validation cohorts with AUROCs of 0.90, 0.79, and 0.87 for prediction of IDH, ATRX, and 1p19q codeletion, respectively. CONCLUSIONS: In the future, such DL-based implementations could ease diagnostic workflows, particularly for situations in which advanced molecular testing is not readily available

    Impact of COVID-19 on Renewable Energy Auctions

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    This is the final version. Available from AURES II via the link in this recordAuctions for renewable energy (RES) support are market-based, competitive bidding processes to identify the most appropriate RES projects to be constructed within a certain time frame and allocate support payments to these projects. Most EU Member States have introduced RES auctions that seem to have resulted in strong price decreases. The COVID-19 pandemic, its consequential lock-down of economic activity, the increased risks for investors and fears about an economic recession, have had profound immediate effects on the energy sector. Power demand has strongly decreased and there is high uncertainty for the mid-term. Industry associations worry that a reduced power demand and tighter budgets could reduce new auction volumes of RES projects.European Commissio

    Authigenic carbonates from the Cascadia subduction zone and their relation to gas hydrate stability

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    Authigenic carbonates are intercalated with massive gas hydrates in sediments of the Cascadia margin. The deposits were recovered from the uppermost 50 cm of sediments on the southern summit of the Hydrate Ridge during the RV Sonne cruise SO110. Two carbonate lithologies that differ in chemistry, mineralogy, and fabric make up these deposits. Microcrystalline high-magnesium calcite (14 to 19 mol% MgCO3) and aragonite are present in both semiconsolidated sediments and carbonate-cemented clasts. Aragonite occurs also as a pure phase without sediment impurities. It is formed by precipitation in cavities as botryoidal and isopachous aggregates within pure white, massive gas hydrate. Variations in oxygen isotope values of the carbonates reflect the mineralogical composition and define two end members: a Mg-calcite with ή18O =4.86‰ PDB and an aragonite with ή18O =3.68‰ PDB. On the basis of the ambient bottom-water temperature and accepted equations for oxygen isotope fractionation, we show that the aragonite phase formed in equilibrium with its pore-water environment, and that the Mg-calcite appears to have precipitated from pore fluids enriched in 18O. Oxygen isotope enrichment probably originates from hydrate water released during gas-hydrate destabilization

    Auctions for Renewable Energy Support II - First insights and results of the Horizon2020 project AURES II

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    This is the final version. Available from Funcas via the link in this recordThe Horizon2020 project AURES II aims at ensuring the effective implementation of auctions for renewable energies in the EU Member States (MS). In recent years, auction schemes for the allocation of support for renewable electricity sources (RES) have been advancing rapidly across Europe. Auctions are considered to have brought down support levels and increased planning capability for RES deployment and state budgets. In some unfortunate cases, they have, however, also resulted in delayed or unrealised projects and increased uncertainty for project developers. A variety of auction designs are still being tested and introduced in EU MS, as well as foreseen by European legislation. Therefore, there is still a need for further assessment and improvement of national auction design and implementation to ensure the future success of RES auctions in Europe. Applying different qualitative and quantitative methods in the various work packages (WPs), the AURES II project partners have already drafted and published a large number of reports and studies. This article aims at comprehensively presenting these results and provide a first overview.European Union Horizon 202

    Observation of direct processes in photoproduction at HERA

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    Jets in photoproduction events have been studied with the ZEUS detector for gammap centre-of-mass energies ranging from 130 to 2 50 GeV. The inclusive jet distributions give evidence for the dominance of resolved photon interactions. In the di-jet sample the direct processes are for the first time clearly isolated. Di-jet cross sections for the resolved and direct processes are given in a restricted kinematic range

    ĐœĐ”Ń‚Đ°Đ»Đ»ĐžĐ·Đ°Ń†ĐžŃ ĐżĐŸĐČĐ”Ń€Ń…ĐœĐŸŃŃ‚Đž ĐșĐ”Ń€Đ°ĐŒĐžĐșĐž В4ĐĄ ĐșĐŸĐŒĐ±ĐžĐœĐžŃ€ĐŸĐČĐ°ĐœĐœŃ‹ĐŒ ŃĐ»Đ”ĐșŃ‚Ń€ĐŸĐœĐœĐŸ-ĐžĐŸĐœĐœĐŸ-ĐżĐ»Đ°Đ·ĐŒĐ”ĐœĐœŃ‹ĐŒ ĐŒĐ”Ń‚ĐŸĐŽĐŸĐŒ

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    ОбъДĐșŃ‚ĐŸĐŒ ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžŃ яĐČĐ»ŃĐ”Ń‚ŃŃ ĐșĐ”Ń€Đ°ĐŒĐžĐșĐ° В4ĐĄ с ĐŒĐ”Ń‚Đ°Đ»Đ»ĐžĐ·ĐžŃ€ĐŸĐČĐ°ĐœĐœĐŸĐč ĐżĐŸĐČĐ”Ń€Ń…ĐœĐŸŃŃ‚ŃŒŃŽ. ĐŠĐ”Đ»ŃŒ Ń€Đ°Đ±ĐŸŃ‚Ń‹ – ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžĐ” струĐșтуры Đž сĐČĐŸĐčстĐČ ŃĐžŃŃ‚Đ”ĐŒ Â«ĐżĐ»Đ”ĐœĐșĐ° (Ti)/(В4ĐĄ-ĐșĐ”Ń€Đ°ĐŒĐžĐșĐ°) ĐżĐŸĐŽĐ»ĐŸĐ¶Đșа» Đž Â«ĐżĐ»Đ”ĐœĐșĐ° (Cu)/(В4ĐĄ-ĐșĐ”Ń€Đ°ĐŒĐžĐșĐ°) ĐżĐŸĐŽĐ»ĐŸĐ¶Đșа», ĐŸĐ±Ń€Đ°Đ±ĐŸŃ‚Đ°ĐœĐœŃ‹Ń… ĐžĐœŃ‚Đ”ĐœŃĐžĐČĐœŃ‹ĐŒ ĐžĐŒĐżŃƒĐ»ŃŒŃĐœŃ‹ĐŒ ŃĐ»Đ”ĐșŃ‚Ń€ĐŸĐœĐœŃ‹ĐŒ пучĐșĐŸĐŒ. В ĐżŃ€ĐŸŃ†Đ”ŃŃĐ” ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžŃ ĐżŃ€ĐŸĐČĐŸĐŽĐžĐ»ĐžŃŃŒ Ń€Đ”ĐœŃ‚ĐłĐ”ĐœĐŸŃ„Đ°Đ·ĐŸĐČŃ‹Đ” ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžĐ”; ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžĐ” ĐżĐŸĐČĐ”Ń€Ń…ĐœĐŸŃŃ‚Đž Đž ĐžĐ·Đ»ĐŸĐŒĐ° ĐŸĐ±Ń€Đ°Đ·Ń†ĐŸĐČ ĐŒĐ”Ń‚ĐŸĐŽĐŸĐŒ сĐșĐ°ĐœĐžŃ€ŃƒŃŽŃ‰Đ”Đč ŃĐ»Đ”ĐșŃ‚Ń€ĐŸĐœĐœĐŸĐč ĐŒĐžĐșŃ€ĐŸŃĐșĐŸĐżĐžĐž; ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžĐ” ĐŒĐžĐșŃ€ĐŸŃ‚ĐČĐ”Ń€ĐŽĐŸŃŃ‚Đž Đž ĐșĐŸŃŃ„Ń„ĐžŃ†ĐžĐ”ĐœŃ‚Đ° ĐČŃĐ·ĐșĐŸŃŃ‚Đž Ń€Đ°Đ·Ń€ŃƒŃˆĐ”ĐœĐžŃ ĐŸĐ±Ń€Đ°Đ·ĐŸĐČ. В Ń€Đ”Đ·ŃƒĐ»ŃŒŃ‚Đ°Ń‚Đ” ĐžŃŃĐ»Đ”ĐŽĐŸĐČĐ°ĐœĐžŃ ŃƒŃŃ‚Đ°ĐœĐŸĐČĐ»Đ”ĐœĐŸ Ń„ĐŸŃ€ĐŒĐžŃ€ĐŸĐČĐ°ĐœĐžŃŽ ĐČ ĐżĐŸĐČĐ”Ń€Ń…ĐœĐŸŃŃ‚ĐœĐŸĐŒ ŃĐ»ĐŸĐ” Ń‚ĐŸĐ»Ń‰ĐžĐœĐŸĐč (5-7) ĐŒĐșĐŒ ĐŒĐœĐŸĐłĐŸŃ„Đ°Đ·ĐœĐŸĐč струĐșтуры эĐČŃ‚Đ”ĐșтОчДсĐșĐŸĐłĐŸ топа, ŃĐŸŃŃ‚ĐŸŃŃ‰Đ”Đč Оз ĐșŃ€ĐžŃŃ‚Đ°Đ»Đ»ĐžŃ‚ĐŸĐČ ĐșарбОЎа Đ±ĐŸŃ€Đ°, ĐŽĐžĐ±ĐŸŃ€ĐžĐŽĐ° Ń‚ĐžŃ‚Đ°ĐœĐ° Đž Ń‚ĐžŃ‚Đ°ĐœĐ°; ŃĐœĐžĐ¶Đ”ĐœĐžĐ” ĐŒĐžĐșŃ€ĐŸŃ‚ĐČĐ”Ń€ĐŽĐŸŃŃ‚Đž ĐŒĐŸĐŽĐžŃ„ĐžŃ†ĐžŃ€ĐŸĐČĐ°ĐœĐœŃ‹Ń… ĐŸĐ±Ń€Đ°Đ·Ń†ĐŸĐČ ĐșĐ”Ń€Đ°ĐŒĐžĐșĐž Ti/В4ĐĄ ĐČ â‰ˆ1,2 раза ĐŸŃ‚ĐœĐŸŃĐžŃ‚Đ”Đ»ŃŒĐœĐŸ ĐŒĐžĐșŃ€ĐŸŃ‚ĐČŃ‘Ń€ĐŽĐŸŃŃ‚Đž ĐžŃŃ…ĐŸĐŽĐœŃ‹Ń… ĐŸĐ±Ń€Đ°Đ·Ń†ĐŸĐČ. ĐžŃĐœĐŸĐČĐœŃ‹Đ” ĐșĐŸĐœŃŃ‚Ń€ŃƒĐșтоĐČĐœŃ‹Đ”, Ń‚Đ”Ń…ĐœĐŸĐ»ĐŸĐłĐžŃ‡Đ”ŃĐșОД Đž Ń‚Đ”Ń…ĐœĐžĐșĐŸ-эĐșŃĐżĐ»ŃƒĐ°Ń‚Đ°Ń†ĐžĐŸĐœĐœŃ‹Đ” хараĐșтДрОстОĐșĐž: Ń‚Đ”ĐŒĐżĐ”Ń€Đ°Ń‚ŃƒŃ€Đ° Ń€Đ°Đ·Đ»ĐŸĐ¶Đ”ĐœĐžŃ >2450 °C; ĐżĐ»ĐŸŃ‚ĐœĐŸŃŃ‚ŃŒ 2,52 Đł/ŃĐŒÂł; Ń‚Đ”ĐżĐ»ĐŸĐżŃ€ĐŸĐČĐŸĐŽĐœĐŸŃŃ‚ŃŒ 121 Вт/(ĐŒĐš) про 300 °К; ĐŒĐžĐșŃ€ĐŸŃ‚ĐČŃ‘Ń€ĐŽĐŸŃŃ‚ŃŒ 49,1 ГПа; ĐŒĐŸĐŽŃƒĐ»ŃŒ ŃƒĐżŃ€ŃƒĐłĐŸŃŃ‚Đž 450 ГПа; ĐżĐŸĐ»ŃƒĐżŃ€ĐŸĐČĐŸĐŽĐœĐžĐș p-топа.The object of the research is B4C ceramics with metallized surface. Objective - to study the structure and properties of systems "film (Ti) / (B4C-ceramic) substrate" and "film (Cu) / (B4C-ceramic) substrate" treated with intense pulsed electron beam. The study carried out X-ray phase study; study the surface and break the samples by scanning electron microscopy; study of microhardness and fracture toughness ratio images. The study showed the formation of a surface layer (5-7) m multiphase eutectic structure consisting of crystallites of boron carbide, titanium diboride, and titanium; decrease in microhardness modified ceramic samples Ti / B4C in ≈1,2 times the microhardness of the initial samples. The basic constructive, technological and technical and operational characteristics: the decomposition temperature of> 2450 ° C; density 2.52 g / cmÂł; thermal conductivity of 121 W / (mK) at 300 ° K; microhardness 49.1 GPa; modulus 450 GPa; p-type semiconductor

    Methane-carbon flow into the benthic food web at cold seeps – a case study from the Costa Rica subduction zone

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    Cold seep ecosystems can support enormous biomasses of free-living and symbiotic chemoautotrophic organisms that get their energy from the oxidation of methane or sulfide. Most of this biomass derives from animals that are associated with bacterial symbionts, which are able to metabolize the chemical resources provided by the seeping fluids. Often these systems also harbor dense accumulations of non-symbiotic megafauna, which can be relevant in exporting chemosynthetically fixed carbon from seeps to the surrounding deep sea. Here we investigated the carbon sources of lithodid crabs (Paralomis sp.) feeding on thiotrophic bacterial mats at an active mud volcano at the Costa Rica subduction zone. To evaluate the dietary carbon source of the crabs, we compared the microbial community in stomach contents with surface sediments covered by microbial mats. The stomach content analyses revealed a dominance of epsilonproteobacterial 16S rRNA gene sequences related to the free-living and epibiotic sulfur oxidiser Sulfurovum sp. We also found Sulfurovum sp. as well as members of the genera Arcobacter and Sulfurimonas in mat-covered surface sediments where Epsilonproteobacteria were highly abundant constituting 10% of total cells. Furthermore, we detected substantial amounts of bacterial fatty acids such as i-C15:0 and C17:1ω6c with stable carbon isotope compositions as low as −53‰ in the stomach and muscle tissue. These results indicate that the white microbial mats at Mound 12 are comprised of Epsilonproteobacteria and that microbial mat-derived carbon provides an important contribution to the crab's nutrition. In addition, our lipid analyses also suggest that the crabs feed on other 13C-depleted organic matter sources, possibly symbiotic megafauna as well as on photosynthetic carbon sources such as sedimentary detritus

    A new MRI rating scale for progressive supranuclear palsy and multiple system atrophy: validity and reliability

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    AIM To evaluate a standardised MRI acquisition protocol and a new image rating scale for disease severity in patients with progressive supranuclear palsy (PSP) and multiple systems atrophy (MSA) in a large multicentre study. METHODS The MRI protocol consisted of two-dimensional sagittal and axial T1, axial PD, and axial and coronal T2 weighted acquisitions. The 32 item ordinal scale evaluated abnormalities within the basal ganglia and posterior fossa, blind to diagnosis. Among 760 patients in the study population (PSP = 362, MSA = 398), 627 had per protocol images (PSP = 297, MSA = 330). Intra-rater (n = 60) and inter-rater (n = 555) reliability were assessed through Cohen's statistic, and scale structure through principal component analysis (PCA) (n = 441). Internal consistency and reliability were checked. Discriminant and predictive validity of extracted factors and total scores were tested for disease severity as per clinical diagnosis. RESULTS Intra-rater and inter-rater reliability were acceptable for 25 (78%) of the items scored (≄ 0.41). PCA revealed four meaningful clusters of covarying parameters (factor (F) F1: brainstem and cerebellum; F2: midbrain; F3: putamen; F4: other basal ganglia) with good to excellent internal consistency (Cronbach α 0.75-0.93) and moderate to excellent reliability (intraclass coefficient: F1: 0.92; F2: 0.79; F3: 0.71; F4: 0.49). The total score significantly discriminated for disease severity or diagnosis; factorial scores differentially discriminated for disease severity according to diagnosis (PSP: F1-F2; MSA: F2-F3). The total score was significantly related to survival in PSP (p<0.0007) or MSA (p<0.0005), indicating good predictive validity. CONCLUSIONS The scale is suitable for use in the context of multicentre studies and can reliably and consistently measure MRI abnormalities in PSP and MSA. Clinical Trial Registration Number The study protocol was filed in the open clinical trial registry (http://www.clinicaltrials.gov) with ID No NCT00211224
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