14 research outputs found

    A Generalized Alternating Method for Bilevel Learning under the Polyak-{\L}ojasiewicz Condition

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    Bilevel optimization has recently regained interest owing to its applications in emerging machine learning fields such as hyperparameter optimization, meta-learning, and reinforcement learning. Recent results have shown that simple alternating (implicit) gradient-based algorithms can match the convergence rate of single-level gradient descent (GD) when addressing bilevel problems with a strongly convex lower-level objective. However, it remains unclear whether this result can be generalized to bilevel problems beyond this basic setting. In this paper, we first introduce a stationary metric for the considered bilevel problems, which generalizes the existing metric, for a nonconvex lower-level objective that satisfies the Polyak-{\L}ojasiewicz (PL) condition. We then propose a Generalized ALternating mEthod for bilevel opTimization (GALET) tailored to BLO with convex PL LL problem and establish that GALET achieves an ϵ\epsilon-stationary point for the considered problem within O~(ϵ−1)\tilde{\cal O}(\epsilon^{-1}) iterations, which matches the iteration complexity of GD for single-level smooth nonconvex problems.Comment: Camera ready versio

    Gasdermin D deficiency attenuates arthritis induced by traumatic injury but not autoantibody-assembled immune complexes

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    BACKGROUND: Gasdermin D (GSDMD) is cleaved by several proteases including by caspase-1, a component of intracellular protein complexes called inflammasomes. Caspase-1 also converts pro-interleukin-1β (pro-IL-1β) and pro-IL-18 into bioactive IL-1β and IL-18, respectively. GSDMD amino-terminal fragments form plasma membrane pores, which mediate the secretion of IL-1β and IL-18 and cause the inflammatory form of cell death pyroptosis. Here, we tested the hypothesis that GSDMD contributes to joint degeneration in the K/BxN serum transfer-induced arthritis (STIA) model in which autoantibodies against glucose-6-phosphate isomerase promote the formation of pathogenic immune complexes on the surface of myeloid cells, which highly express the inflammasomes. The unexpected outcomes with the STIA model prompted us to determine the role of GSDMD in the post-traumatic osteoarthritis (PTOA) model caused by meniscus ligamentous injury (MLI) based on the hypothesis that this pore-forming protein is activated by signals released from damaged joint tissues. METHODS: Gsdmd RESULTS: GSDMD levels were higher in serum-inoculated paws compared to PBS-injected paws. Unexpectedly, ablation of GSDMD failed to reduce joint swelling and osteolysis, suggesting that GSDMD was dispensable for the pathogenesis of STIA. GSDMD levels were also higher in MLI compared to sham-operated joints. Importantly, ablation of GSDMD attenuated MLI-associated cartilage degradation (p = 0.0097), synovitis (p = 0.014), subchondral bone sclerosis (p = 0.0006), and subchondral bone plate thickness (p = 0.0174) based on histopathological and μCT analyses. CONCLUSION: GSDMD plays a key role in the pathogenesis of PTOA, but not STIA, suggesting that its actions in experimental arthropathy are tissue context-specific

    Multi-Attribute Decision Making Based on Probabilistic Neutrosophic Hesitant Fuzzy Choquet Aggregation Operators

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    Take the third-party logistics providers (3PLs) as an example, according to the characteristics of correlation between attributes in multi-attribute decision-making, two Choquet aggregation operators adoping probabilistic neutrosophic hesitation fuzzy elements (PNHFEs) are proposed to cope with the situations of correlation among criterions. This measure not only provides support for the correlation phenomenon between internal attributes, but also fully concerns the incidental uncertainty of the external space. Our goal is to make it easier for decision makers to cope with this uncertainty, thus we establish the notion of probabilistic neutrosophic hesitant fuzzy Choquet averaging (geometric) (PNHFCOA, PNHFCOG) operator. Based on this foundation, a method for aggregating decision makers’ information is proposed, and then the optimal decision scheme is obtained. Finally, an example of selecting optimal 3PL is given to demonstrate the objectivity of the above-mentioned standpoint

    Prevention and control of zoonoses at their source: from the Chinese perspective

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    Zoonoses are a significant public health concern and cause considerable socioeconomic problems globally. The emergence of severe acute respiratory syndrome (SARS), highly pathogenic avian influenza (HPAI), and Ebola virus disease (EVD) has had a significant effect on the national economy and public health in China, and other countries. This review analyzed zoonotic disease issues faced by China, and the main factors contributing to the risk of zoonotic disease. The Chinese government has devised new strategies and has taken measures to deal with the challenges of these diseases, and the prevention and control of zoonoses at their source. A strategy that is suited to China's national conditions, is proposed

    The efficacy and safety of tranexamic acid in rheumatoid arthritis patients undergoing simultaneous bilateral total knee arthroplasty: a multicenter retrospective study

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    Abstract Background The efficacy and safety of tranexamic acid (TXA) in reducing blood loss following total knee arthroplasty (TKA) in patients with osteoarthritis have been widely confirmed. However, there is still a paucity of the evidences regarding the effectiveness of TXA in patients with rheumatoid arthritis (RA). The purpose of the study is to explore the efficacy and safety of intravenous TXA on blood loss and transfusion risk following simultaneous bilateral TKA (SBTKA) in patients with RA. Methods As a multicenter retrospective study, a total of 74 patients diagnosed with RA who underwent SBTKA were assigned into TXA group (15 mg/kg intravenous TXA before skin incision, n = 50) and control group (no TXA use, n = 24). The primary outcomes were total blood loss (TBL) and intraoperative blood loss (IBL). The secondary outcomes were hemoglobin (Hb) and hematocrit (Hct) drop on postoperative day 3, transfusion rate and volume, ambulation time, length of stay, hospitalization expenses and the incidence of complications. Results The mean TBL, IBL and transfusion volume in TXA group were significantly lower than those in control group. The Hb and Hct drop on postoperative day 3 in control group were higher than those in TXA group (p0.05). Conclusions TXA could effectively reduce blood loss, decrease transfusion risk, shorten ambulation time and length of stay following SBTKA in patients with RA, without increasing the risk of complications

    Improving Nelumbo nucifera genome assemblies using high-resolution genetic maps and BioNano genome mapping reveals ancient chromosome rearrangements

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    individuals and validated by adding 197 simple sequence repeat (SSR) markers. Additionally, a BioNano optical map covering 86.20% of the 'Chinese Tai-zi' genome was constructed. The draft assembly of 'Chinese Tai-zi' was improved based on the BioNano optical map, showing an increase of the scaffold N50 from 0.989 Mb to 1.48 Mb. Using a combination of multiple maps, 97.9% of the scaffolds in the 'Chinese Tai-zi' draft assembly and 97.6% of the scaffolds in the 'China Antique' draft assembly were anchored into pseudo-chromosomes, and the centromere regions along the pseudo-chromosomes were identified. An evolutionary scenario was proposed to reach the modern N. nucifera karyotype from the seven ancestral eudicot chromosomes. The present study provides the highest-resolution linkage map, the optical map and chromosome level genome assemblies for N. nucifera, which are valuable for the breeding and cultivation of N. nucifera and future studies of comparative and evolutionary genomics in angiosperms. This article is protected by copyright. All rights reserved
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