776 research outputs found
Minimalist and High-Performance Semantic Segmentation with Plain Vision Transformers
In the wake of Masked Image Modeling (MIM), a diverse range of plain,
non-hierarchical Vision Transformer (ViT) models have been pre-trained with
extensive datasets, offering new paradigms and significant potential for
semantic segmentation. Current state-of-the-art systems incorporate numerous
inductive biases and employ cumbersome decoders. Building upon the original
motivations of plain ViTs, which are simplicity and generality, we explore
high-performance `minimalist' systems to this end. Our primary purpose is to
provide simple and efficient baselines for practical semantic segmentation with
plain ViTs. Specifically, we first explore the feasibility and methodology for
achieving high-performance semantic segmentation using the last feature map. As
a result, we introduce the PlainSeg, a model comprising only three 33
convolutions in addition to the transformer layers (either encoder or decoder).
In this process, we offer insights into two underlying principles: (i)
high-resolution features are crucial to high performance in spite of employing
simple up-sampling techniques and (ii) the slim transformer decoder requires a
much larger learning rate than the wide transformer decoder. On this basis, we
further present the PlainSeg-Hier, which allows for the utilization of
hierarchical features. Extensive experiments on four popular benchmarks
demonstrate the high performance and efficiency of our methods. They can also
serve as powerful tools for assessing the transfer ability of base models in
semantic segmentation. Code is available at
\url{https://github.com/ydhongHIT/PlainSeg}
Adaptive robust control for networked strict-feedback nonlinear systems with state and input quantization
Funding Information: Funding: This work was supported in part by the National Natural Science Foundation of China under Grant 62022031, Grant 61773135, Grant U20A20188; and in part by the Fundamental Research Funds for the Central Universities. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Backstepping method is a successful approach to deal with the systems in strict-feedback form. However, for networked control systems, the discontinuous virtual law caused by state quantization introduces huge challenges for its applicability. In this article, a quantized adaptive robust control approach in backsetpping framework is developed in this article for networked strict-feedback nonlinear systems with both state and input quantization. In order to prove the efficiency of the designed control scheme, a novel form of Lyapunov candidate function was constructed in the process of analyzing the stability, which is applicable for the systems with nondifferentiable virtual control law. In particular, the state and input quantizers can be in any form as long as they meet the sector-bound condition. The theoretic result shows that the tracking error is determined by the pregiven constants and quantization errors, which are also verified by the simulation results.publishersversionpublishe
Joint Antenna Selection and Precoding Optimization for Small-Cell Network with Minimum Power Consumption
We focus on the power consumption problem for a downlink multiuser small-cell network (SCN) considering both the quality of service (QoS) and power constraints. First based on a practical power consumption model taking into account both the dynamic transmit power and static circuit power, we formulate and then transform the power consumption optimization problem into a convex problem by using semidefinite relaxation (SDR) technique and obtain the optimal solution by the CVX tool. We further note that the SDR-based solution becomes infeasible for realistic implementation due to its heavy backhaul burden and computational complexity. To this end, we propose an alternative suboptimal algorithm which has low implementation overhead and complexity, based on minimum mean square error (MMSE) precoding. Furthermore, we propose a distributed correlation-based antenna selection (DCAS) algorithm combining with our optimization algorithms to reduce the static circuit power consumption for the SCN. Finally, simulation results demonstrate that our proposed suboptimal algorithm is very effective on power consumption minimization, with significantly reduced backhaul burden and computational complexity. Moreover, we show that our optimization algorithms with DCAS have less power consumption than the other benchmark algorithms
Blood urea nitrogen in the prediction of in-hospital mortality of patients with acute aortic dissection
Background: Blood urea nitrogen (BUN) has been shown to be associated with adverse cardiovascular disease outcomes. The aim of the present study was to evaluate the prognostic role of BUN in patients with acute aortic dissection (AAD). Hypothesis: BUN has correlation with in-hospital mortality of patients with AAD. Methods: Patients admitted to the emergency room within the first 24 h of onset of AAD were included in the study. BUN levels were measured on admission and the endpoints were mortality during hospiÂtalization after receiving surgical or endovascular repair. Results: A total of 192 patients with AAD were enrolled. During hospitalization, 19 patients died and 173 patients survived. Increased levels of BUN (8.9 [7.0–9.7] vs. 6.0 [5.1–7.2] mmol/L, p < 0.001) were found in non-survivors compared with those survived. Using multivariable logistic analysis, BUN was an independent predictor of in-hospital mortality in patients with AAD (OR 1.415, 95% CI 1.016–1.971, p = 0.040). Furthermore, using receiver operating characteristic analysis, the optimal cutoff value for BUN was 6.95 mmol/L. Under this value, the area under the curve was 0.785 (95% CI 0.662–0.909, p < 0.001) and the sensitivity and specificity to predict in-hospital mortality was 78.9%, and 72.2%, respectively. Conclusions: Admission BUN levels were an independent predictor for in hospital mortality in paÂtients with AAD
Assessment of the therapeutic potential of anti-miR 24 and anti-miR 34 in cardiac diseases
Purpose: To study the therapeutic effects of anti-miR-24 and anti-miR-34 in cardiac diseasesMethods: H9c2 rat cardiomyocyte cell lines were transfected with the synthetic oligonucleotides antimiR-24 and anti-miR-34 which reduced the expressions of miR-24 and miR-34. Proliferation assay, real time-polymerase chain reaction (RT-PCR) and immunoblotting were carried out to determine the effect of the transfections on cardiomyocyte proliferation, expressions of miR-24 and miR-34, as well as expressions of the target genes, TGF-β1 and E2F3.Results: The proliferation ability of the transfected cells was decreased significantly, relative to negative control. In contrast, percentage apoptosis was higher in the negative control group than in transfected cells. The expression profiles of anti-miR-24 and anti-miR-34 were significantly reduced, when compared to negative control. These results were further confirmed using immunoblot which revealed that the expression of the target genes, TGF-β1 and E2F3, were upregulated in the transfected cells.Conclusion: These results suggest that the synthetic oligonucleotides (anti-miR-24 and anti-miR-34) might be useful in developing therapeutic drug targets for cardiac diseases by suppressing the expressions of miR-24 and miR-34.
Keywords: H9c2rat cardiomyocyte miRNA, Anti-miR-24, Anti-miR-34, Cardiac disease
Stable smectic phase in suspensions of polydisperse colloidal platelets with identical thickness
6 pages, 6 figures.-- PACS nrs.: 61.30.Eb, 64.70.M−, 81.16.Dn, 82.70.Dd.-- ArXiv pre-print available at: http://arxiv.org/abs/0909.2625We report the nematic and smectic ordering in an aqueous suspension of monolayer α-Zirconium phosphate platelets possessing a high polydispersity in diameter but uniform thickness. We observe an isotropic-nematic transition as the platelet volume fraction increases, followed by the formation of a smectic, an elusive phase that has been rarely seen in discotic liquid crystals. The smectic phase is characterized by x-ray diffraction high-resolution transmission electron microscopy, and optical microscopy. The phase equilibria in this highly polydisperse suspension are rationalized in terms of a theoretical approach based on density-functional theory.Acknowledgment is made to the donors of ACS Petroleum Research Fund (Grant No. 45303-G7) and to the Dow Chemical Co. This work has been partly financed by start-up funds from Texas Engineering Experimental Station and Texas A&M University, by Grants No. NANOFLUID, No. MOSAICO, and No. S-0505/ESP-0299 from Comunidad Autónoma de Madrid (Spain), and Grants No. FIS2005-05243-C02-01, No.
FIS2007-65869-C03-01, No. FIS2008-05865-C02-02, and No. FIS2007-65869-C03-C01 from Ministerio de Educación y Ciencia (Spain).Publicad
Decreased Glomerular Filtration Rate Is Associated with Mortality and Cardiovascular Events in Patients with Hypertension: A Prospective Study
BACKGROUND: Few studies reported the associations between decreased glomerular filtration rate (GFR) and mortality, coronary heart disease (CHD), and stroke in hypertensive patients. We aim to assess the associations between GFR and mortality, CHD, and stroke in hypertensive patients and to evaluate whether low GFR can improve the prediction of these outcomes in addition to conventional cardiovascular risk factors. METHODS AND FINDINGS: This is an observational prospective study and 3,711 eligible hypertensive patients aged ≥5 years from rural areas of China were used for the present analysis. The associations between eGFR and outcomes, followed by a median of 4.9 years, were evaluated using Cox proportional hazards models adjusting for other potential confounders. Low eGFR was independently associated with risk of all-cause mortality, cardiovascular mortality, and incident stroke [multivariable adjusted hazard ratios (95% confidence intervals) for eGFR <60 ml/min/1.73 m(2) relative to eGFR ≥90 ml/min/1.73 m(2) were 1.824 (1.047-3.365), 2.371 (1.109-5.068), and 2.493 (1.193-5.212), respectively]. We found no independent association between eGFR and the risk of CHD. For 4-year all-cause and cardiovascular mortality, integrated discrimination improvement (IDI) was positive when eGFR were added to traditional risk factors (1.51%, P = 0.016, and 1.99%, P = 0.017, respectively). For stroke and CHD events, net reclassification improvements (NRI) were 5.9% (P = 0.012) and 1.8% (P = 0.083) for eGFR, respectively. CONCLUSIONS: We have established an inversely independent association between eGFR and all-cause mortality, cardiovascular mortality, and stroke in hypertensive patients in rural areas of China. Further, addition of eGFR significantly improved the prediction of 4-year mortality and stroke over and above that of conventional risk factors. We recommend that eGFR be incorporated into prognostic assessment for patients with hypertension in rural areas of China. LIMITATIONS: We did not have sufficient information on atrial fibrillation to control for the potential covariate. These associations should be further confirmed in future
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