87 research outputs found
Entangled View-Epipolar Information Aggregation for Generalizable Neural Radiance Fields
Generalizable NeRF can directly synthesize novel views across new scenes,
eliminating the need for scene-specific retraining in vanilla NeRF. A critical
enabling factor in these approaches is the extraction of a generalizable 3D
representation by aggregating source-view features. In this paper, we propose
an Entangled View-Epipolar Information Aggregation method dubbed EVE-NeRF.
Different from existing methods that consider cross-view and along-epipolar
information independently, EVE-NeRF conducts the view-epipolar feature
aggregation in an entangled manner by injecting the scene-invariant appearance
continuity and geometry consistency priors to the aggregation process. Our
approach effectively mitigates the potential lack of inherent geometric and
appearance constraint resulting from one-dimensional interactions, thus further
boosting the 3D representation generalizablity. EVE-NeRF attains
state-of-the-art performance across various evaluation scenarios. Extensive
experiments demonstate that, compared to prevailing single-dimensional
aggregation, the entangled network excels in the accuracy of 3D scene geometry
and appearance reconstruction. Our code is publicly available at
https://github.com/tatakai1/EVENeRF.Comment: Accepted by CVPR-202
C2F2NeUS: Cascade Cost Frustum Fusion for High Fidelity and Generalizable Neural Surface Reconstruction
There is an emerging effort to combine the two popular 3D frameworks using
Multi-View Stereo (MVS) and Neural Implicit Surfaces (NIS) with a specific
focus on the few-shot / sparse view setting. In this paper, we introduce a
novel integration scheme that combines the multi-view stereo with neural signed
distance function representations, which potentially overcomes the limitations
of both methods. MVS uses per-view depth estimation and cross-view fusion to
generate accurate surfaces, while NIS relies on a common coordinate volume.
Based on this strategy, we propose to construct per-view cost frustum for finer
geometry estimation, and then fuse cross-view frustums and estimate the
implicit signed distance functions to tackle artifacts that are due to noise
and holes in the produced surface reconstruction. We further apply a cascade
frustum fusion strategy to effectively captures global-local information and
structural consistency. Finally, we apply cascade sampling and a
pseudo-geometric loss to foster stronger integration between the two
architectures. Extensive experiments demonstrate that our method reconstructs
robust surfaces and outperforms existing state-of-the-art methods.Comment: Accepted by ICCV202
Platelet Count Predicts Adverse Clinical Outcomes After Ischemic Stroke or TIA: Subgroup Analysis of CNSR II
Background: The clinical significance of platelet count (PC) for ischemic cerebrovascular disease is not well-established and further risk stratification according to baseline PC within normal range has not been reported before. We aim to evaluate the prognostic effect of baseline circulating PC within normal range on the risk of long-term recurrent stroke, mortality and functional outcomes after ischemic stroke or TIA.Methods: We derived data from eligible patients with ischemic stroke or TIA from the China National Stroke Registry (CNSR) II. Participants were divided into quintiles according to baseline PC within normal range (100–450 × 109/L). Multivariable cox regression and logistic regression were adopted to explore the correlation of baseline PC with recurrent stroke, mortality and poor functional outcomes (modified Rankin Scale 3~6) within 1-year follow-up.Results: Among the16842 eligible participants, the average age was 64.7 ± 11.9, 1,241 (7.4%) had recurrent stroke, 1,377 (8.2%) died, and 3,557 (21.1%) ended up with poor functional outcomes after 1-year follow-up. Compared with the third PC quintile (186–212 × 109/L), patients in the top quintile (249–450 × 109/L) presented with increased risk of recurrent stroke (adjusted hazard ratio 1.21, [1.02–1.45]), all-cause mortality (adjusted hazard ratio 1.43, [1.19–1.73]), and poor functional outcome (adjusted odds ratio 1.49, [1.28–1.74]), while patients in the lowest PC quintile(100–155 × 109/L) had higher risk of poor functional outcome (adjusted odds ratio 1.19, [1.02–1.38]).Conclusion: In ischemic stroke or TIA patients with platelet count within normal range, platelet count may be a qualified predictor for long-term recurrent stroke, mortality, and poor functional outcome
Substantial Progress Yet Significant Opportunity for Improvement in Stroke Care in China
BACKGROUND AND PURPOSE: Stroke is a leading cause of death in China. Yet the adherence to guideline-recommended ischemic stroke performance metrics in the past decade has been previously shown to be suboptimal. Since then, several nationwide stroke quality management initiatives have been conducted in China. We sought to determine whether adherence had improved since then.
METHODS: Data were obtained from the 2 phases of China National Stroke Registries, which included 131 hospitals (12 173 patients with acute ischemic stroke) in China National Stroke Registries phase 1 from 2007 to 2008 versus 219 hospitals (19 604 patients) in China National Stroke Registries phase 2 from 2012 to 2013. Multiple regression models were developed to evaluate the difference in adherence to performance measure between the 2 study periods.
RESULTS: The overall quality of care has improved over time, as reflected by the higher composite score of 0.76 in 2012 to 2013 versus 0.63 in 2007 to 2008. Nine of 13 individual performance metrics improved. However, there were no significant improvements in the rates of intravenous thrombolytic therapy and anticoagulation for atrial fibrillation. After multivariate analysis, there remained a significant 1.17-fold (95% confidence interval, 1.14-1.21) increase in the odds of delivering evidence-based performance metrics in the more recent time periods versus older data. The performance metrics with the most significantly increased odds included stroke education, dysphagia screening, smoking cessation, and antithrombotics at discharge.
CONCLUSIONS: Adherence to stroke performance metrics has increased over time, but significant opportunities remain for further improvement. Continuous stroke quality improvement program should be developed as a national priority in China
Preparation and optimization of poly (lactic-co-glycolic acid) rod-shaped particles in nano size range for paclitaxel delivery
Nanoparticle shape has been acknowledged as an important design parameter due to its influence on nanoparticle interaction with biological systems. However, there is lacking of simple and scalable preparation technique for drug loaded non-spherical polymeric nanoparticles for a long time, thus hindering the potential applications. Although our previous research has modified the traditional emulsion solvent evaporation technique by adding guest molecules to prepare non-spherical poly (lactic-co-glycolic acid) (PLGA) particles, it is difficult to obtain nano-sized rods with minor axis less than 200 nm, which may have great potential in cancer therapy. Herein, in present research, the two-step ESE method was used and optimized to prepare poly (lactic-co-glycolic acid) nanorods for paclitaxel delivery. Firstly, the single-factor experiment was used to screen the influence of multi-factors including type of guest molecules, concentration of guest molecules, emulsification method, surfactant concentration, oil volume, poly (lactic-co-glycolic acid) concentration on the size and shape to determine the range of variables; based on the above range, a multi-factor and multi-level orthogonal experiment was designed. The formula is evaluated by the rod fabrication yield and the aspect ratio of major axis to minor axis. The results showed that the yield of nanorods in the optimal formula was 99% and the aspect ratio was 5.35 ± 2.05 with the minor axis of 135.49 ± 72.66 nm, and major axis of 657.77 ± 307.63 nm. In addition, the anti-cancer drug paclitaxel was successfully encapsulated in PLGA nanorods by the same technique. Our results not only enrich the ESE technique for preparing small sized poly (lactic-co-glycolic acid) nanorods, but also envision the potential application of nanorods for targeted cancer therapy with the delivery of paclitaxel
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