194 research outputs found

    Changes in Adipokines following Laparoscopic Roux-en-Y Gastric Bypass Surgery in Chinese Individuals with Type 2 Diabetes Mellitus and BMI of 22–30 kg·m −2

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    Aims. Although altered endocrine changes following bariatric surgery in morbidly obese patients with diabetes have been demonstrated by previous studies, little is known about their effects on low BMI patients of T2DM. We investigated the changes in adipokines and sICAM-1 in Chinese subjects with low BMI and T2DM after LRYGB and explored their relationship with postsurgical insulin sensitivity. Methods. Plasma levels of adiponectin, sICAM-1, fasting glucose, glycated hemoglobin, and fasting insulin and serum levels of visfatin were measured before and at three months after LRYGB in 33 T2DM patients with BMI of 22–30 kg·m−2. Results. Significant reductions in anthropometric measurements and indicators of glucose and lipid metabolism and moderate reductions in insulin resistance and fasting insulin were observed at three months after LRYGB. Postoperative adiponectin level () was increased compared to the preoperative level, whereas visfatin () and sICAM-1 () were lower than that before surgery. Serum adiponectin negatively correlated with HOMA-IR and FIns both preoperatively and at three months after surgery, and visfatin positively correlated with HOMA-IR and FIns both preoperatively and postoperatively. Conclusion. Changes in adipokines were related to an improvement in postsurgical insulin sensitivity, which was predicted by weight loss after LRYGB even in low BMI patients with T2DM

    Adversarial Attacks and Defenses for Semantic Communication in Vehicular Metaverses

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    For vehicular metaverses, one of the ultimate user-centric goals is to optimize the immersive experience and Quality of Service (QoS) for users on board. Semantic Communication (SemCom) has been introduced as a revolutionary paradigm that significantly eases communication resource pressure for vehicular metaverse applications to achieve this goal. SemCom enables high-quality and ultra-efficient vehicular communication, even with explosively increasing data traffic among vehicles. In this article, we propose a hierarchical SemCom-enabled vehicular metaverses framework consisting of the global metaverse, local metaverses, SemCom module, and resource pool. The global and local metaverses are brand-new concepts from the metaverse's distribution standpoint. Considering the QoS of users, this article explores the potential security vulnerabilities of the proposed framework. To that purpose, this study highlights a specific security risk to the framework's SemCom module and offers a viable defense solution, so encouraging community researchers to focus more on vehicular metaverse security. Finally, we provide an overview of the open issues of secure SemCom in the vehicular metaverses, notably pointing out potential future research directions

    Privacy-preserving Intelligent Resource Allocation for Federated Edge Learning in Quantum Internet

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    Federated edge learning (FEL) is a promising paradigm of distributed machine learning that can preserve data privacy while training the global model collaboratively. However, FEL is still facing model confidentiality issues due to eavesdropping risks of exchanging cryptographic keys through traditional encryption schemes. Therefore, in this paper, we propose a hierarchical architecture for quantum-secured FEL systems with ideal security based on the quantum key distribution (QKD) to facilitate public key and model encryption against eavesdropping attacks. Specifically, we propose a stochastic resource allocation model for efficient QKD to encrypt FEL keys and models. In FEL systems, remote FEL workers are connected to cluster heads via quantum-secured channels to train an aggregated global model collaboratively. However, due to the unpredictable number of workers at each location, the demand for secret-key rates to support secure model transmission to the server is unpredictable. The proposed systems need to efficiently allocate limited QKD resources (i.e., wavelengths) such that the total cost is minimized in the presence of stochastic demand by formulating the optimization problem for the proposed architecture as a stochastic programming model. To this end, we propose a federated reinforcement learning-based resource allocation scheme to solve the proposed model without complete state information. The proposed scheme enables QKD managers and controllers to train a global QKD resource allocation policy while keeping their private experiences local. Numerical results demonstrate that the proposed schemes can successfully achieve the cost-minimizing objective under uncertain demand while improving the training efficiency by about 50\% compared to state-of-the-art schemes

    Privacy Attacks and Defenses for Digital Twin Migrations in Vehicular Metaverses

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    The gradual fusion of intelligent transportation systems with metaverse technologies is giving rise to vehicular metaverses, which blend virtual spaces with physical space. As indispensable components for vehicular metaverses, Vehicular Twins (VTs) are digital replicas of Vehicular Metaverse Users (VMUs) and facilitate customized metaverse services to VMUs. VTs are established and maintained in RoadSide Units (RSUs) with sufficient computing and storage resources. Due to the limited communication coverage of RSUs and the high mobility of VMUs, VTs need to be migrated among RSUs to ensure real-time and seamless services for VMUs. However, during VT migrations, physical-virtual synchronization and massive communications among VTs may cause identity and location privacy disclosures of VMUs and VTs. In this article, we study privacy issues and the corresponding defenses for VT migrations in vehicular metaverses. We first present four kinds of specific privacy attacks during VT migrations. Then, we propose a VMU-VT dual pseudonym scheme and a synchronous pseudonym change framework to defend against these attacks. Additionally, we evaluate average privacy entropy for pseudonym changes and optimize the number of pseudonym distribution based on inventory theory. Numerical results show that the average utility of VMUs under our proposed schemes is 33.8% higher than that under the equal distribution scheme, demonstrating the superiority of our schemes.Comment: 8 pages, 6 figure

    Leptin and melatonin’s effects on OVX rodents’ bone metabolism

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    PurposeThis study aims to examine the effects of leptin and melatonin intervention on bone metabolism in ovariectomize (OVX) rodents, as well as their potential mechanisms of action.MethodsPrepare an OVX model of osteoporosis in rodents and validate the model by collecting bilateral tibia samples for Micro-CT scanning and histological analysis. A control group of normal size, the OVX group, the OVX+Sema4D (Semaphorin 4D) group, the OVX+Sema4D+Leptin group, the OVX+Sema4D+ Melatonin(MT) group and the OVX+Sema4D+Leptin+ MT group were the experimental groups. Adenovirus vector construction and tibial medullary injection validation were conducted in accordance with the aforementioned experimental groups. Four groups of rats were injected with the Sema4D overexpression adenovirus vector into the tibial medullary cavity, and two groups were injected with the Leptin overexpression adenovirus vector. The repair of osteoporosis was observed using micro-CT and histological analysis. Immunohistochemical detection of bone morphogenetic protein-2 (BMP-2) expression in bone tissue was employed to ascertain the amount of osteoclasts in the upper tibial metaphysis, utilizing TRAP(tartrate-resistant acid phosphatase) staining.ResultsIncreased levels of BV/TV, Tb.N, BMD, and BMC were seen in the OVX+ Sema4D+Leptin, OVX+ Sema4D+MT, and OVX+ Sema4D+Leptin+ MT groups compared to the OVX group, whereas Tb. Sp levels were lowered. When compared to the Sema4D overexpression group, the trabecular bone structure of the OVX + Sema4D + Leptin, OVX + Sema4D + MT, and OVX + Sema4D + Leptin + MT groups is largely intact, tends to be closer, and the amount of trabecular bone increases. The OVX + Sema4D + Leptin + MT group in particular.The expression of BMP-2 was dramatically upregulated (p<0.05), the number of TRAP-stained osteoclasts was significantly reduced (p<0.05), and BALP(bone-derived alkaline phosphatase) and TRAP-5b(tartrate-resistant acid phosphatase-5b) activities were significantly downregulated (p<0.05).ConclusionIn rats with osteoporosis, leptin and melatonin can be seen to augment the trabecular microstructure of the bone, augment bone growth, diminish trabecular harm, and mend the bone. The combined effect is more powerful

    Personalized and targeted therapy of esophageal squamous cell carcinoma: an update: Personalized and targeted therapy of esophageal squamous cell carcinoma

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    Esophageal squamous cell carcinoma (ESCC) is a deadly disease that requires extensive research. In this review, we update recent progress in the research area of targeted therapy for ESCC. Sox2 and its associated proteins (e.g., ΔNp63α), which regulate lineage survival of ESCC cells, are proposed as therapeutic targets. It is believed that targeting the lineage-survival mechanism may be more effective than targeting other mechanisms. With the advent of a new era of personalized targeted therapy, there is a need to move from the tumor-centric model into an organismic model

    Orbital angular momentum vector modes (de)multiplexer based on multimode micro-ring

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    Orbital angular momentum (OAM) multiplexing has emerged as an important method to increase the communication capacities in future optical information technologies. In this work, we demonstrate a silicon integrated OAM (de)multiplexer with a very simple structure. By simply tapping the evanescent wave of two different whispering gallery modes rotating inside a multimodal micro-ring resonator, four in-plane waveguide modes are converted to four free-space vector OAM beams with high mode purity. We further demonstrate chip-to-chip OAM multiplexing transmission using a pair of silicon devices, which shows low-level mode crosstalk and favorable link performance

    Association between N, N-diethyl-m-toluamide exposure and the odds of kidney stones in US adults: a population-based study

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    BackgroundCurrently, there is limited research on the specific relationship between N, N-diethyl-m-toluamide (DEET) exposure and the odds of kidney stones. We aimed to investigate the relationship between DEET exposure and the prevalence of kidney stones.MethodsWe included 7,567 qualified participants in our research from the 2007–2016 NHANES survey. We carried out three logistic regression models to explore the potential association between DEET exposure and the odds of kidney stones. Spline smoothing with generalized additive models (GAM) was utilized to assess the non-linear relationship and restricted cubic spline (RCS) curves was to determine the dose–response association. Multivariate regression models were used to conduct stratified analysis and sensitivity analysis.ResultsBaseline characteristics of study participants presented the distribution of covariables. Regression analysis revealed that the odds of kidney stones were positively associated with the main metabolites of 3-diethyl-carbamoyl benzoic acid (DCBA) (log2) (OR = 1.05, 95% CI 1.02 to 1.08). The fourth quartile of urine DCBA showed a greater risk of kidney stones in the fully adjusted model (OR = 1.36, 95% CI 1.08 to 1.72). Another DEET metabolite of N, N-diethyl-3-hydroxymethylbenzamide (DHMB) was used to confirm the accuracy and stability of the results. The spline smoothing curve represented two main DEET metabolites had similar no-linear relationships and a positive trend with kidney stones proportion. RCS implied that the incidence of kidney stones rose with increasing levels of DEET exposure. High-risk groups on kidney stones were exhibited by stratified analysis under DEET exposure.ConclusionOur study suggests that DEET exposure is positively associated with odds of kidney stones. Further investigation into the underlying processes of this association is required to guide the prevention and treatment of kidney stones
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