57 research outputs found

    Microtissues Enhance Smooth Muscle Differentiation and Cell Viability of hADSCs for Three Dimensional Bioprinting

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    Smooth muscle differentiated human adipose derived stem cells (hADSCs) provide a crucial stem cell source for urinary tissue engineering, but the induction of hADSCs for smooth muscle differentiation still has several issues to overcome, including a relatively long induction time and equipment dependence, which limits access to abundant stem cells within a short period of time for further application. Three-dimensional (3D) bioprinting holds great promise in regenerative medicine due to its controllable construction of a designed 3D structure. When evenly mixed with bioink, stem cells can be spatially distributed within a bioprinted 3D structure, thus avoiding drawbacks such as, stem cell detachment in a conventional cell-scaffold strategy. Notwithstanding the advantages mentioned above, cell viability is often compromised during 3D bioprinting, which is often due to pressure during the bioprinting process. The objective of our study was to improve the efficiency of hADSC smooth muscle differentiation and cell viability of a 3D bioprinted structure. Here, we employed the hanging-drop method to generate hADSC microtissues in a smooth muscle inductive medium containing human transforming growth factor β1 and bioprinted the induced microtissues onto a 3D structure. After 3 days of smooth muscle induction, the expression of α-smooth muscle actin and smoothelin was higher in microtissues than in their counterpart monolayer cultured hADSCs, as confirmed by immunofluorescence and western blotting analysis. The semi-quantitative assay showed that the expression of α-smooth muscle actin (α-SMA) was 0.218 ± 0.077 in MTs and 0.082 ± 0.007 in Controls; smoothelin expression was 0.319 ± 0.02 in MTs and 0.178 ± 0.06 in Controls. Induced MTs maintained their phenotype after the bioprinting process. Live/dead and cell count kit 8 assays showed that cell viability and cell proliferation in the 3D structure printed with microtissues were higher at all time points compared to the conventional single-cell bioprinting strategy (mean cell viability was 88.16 ± 3.98 vs. 61.76 ± 15% for microtissues and single-cells, respectively). These results provide a novel way to enhance the smooth muscle differentiation of hADSCs and a simple method to maintain better cell viability in 3D bioprinting

    A Privacy-Preserving KYC-Compliant Identity Scheme for Accounts on All Public Blockchains

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    Cryptocurrencies have the potential to enable socioeconomic growth throughout the world by offering easier access to capital and financial services. However, many virtual asset service providers (VASPs) that offer cryptocurrency services lack identity management and can be accessed anonymously, which has led to their services being exploited by criminal activities such as money laundering and illegal foreign exchange. Such crimes have a negative impact on socioeconomic sustainability. Building identity systems on blockchains can help VASPs improve their identity management to combat cryptocurrency-based crimes so VASPs can better serve the social economy and achieve their sustainability goals. However, existing solutions have privacy problems because the identity provider can associate users’ identities with their wallet accounts. In addition, there is currently no solution that can support all public blockchains unconditionally, as current solutions can only support EVM-compliant blockchains or require additional work to support new blockchains. This article proposes a KYC (know your customer)-compliant identity scheme based on Ethereum using Merkle trees and smart contracts. The identity and wallet accounts are linked by the user rather than the KYC provider so, in general, no one but the user knows the association between the wallet accounts and the identity, which protects privacy. For suspicious accounts, supervisors can trace their identities and thus achieve supervision. In addition, the scheme supports identifying accounts on all public blockchains by using Merkle trees and smart contracts to bind accounts on multiple blockchains to one identity and no extra work is required. Moreover, the scheme supports users to prove that their attributes meet the requirements of VASPs by adopting the BBS+ signature and the Sigma protocol

    Dynamic Transaction Confirmation Sharding Protocol for Alliance Chain

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    Alliance chain has gained widespread popularity in industrial and commercial fields due to its multi-centralization and node manageability. Current implementations of the alliance chain suffer from scalability obstacles, such as communication congestion and throughput drop, when the number of nodes increases. In this paper, a novel dynamic transaction confirmation sharding protocol is proposed, which improves transaction processing efficiency by partitioning nodes and assigning different transactions to different shards. It utilizes dynamic transaction confirmation consensus as a sharding intra-consensus mechanism to minimize message size and package transactions into microblocks, which modifies communication content during transaction propagation among shards and reduces network congestion and shard reconfigure cost. The protocol leverages a review system and reputation model to identify and punish malicious nodes and also incorporates a verifiable random function for node configuration, which ensures a sufficient number of honest nodes within the shard and prevents repeated consensus processes. Simulation results show that the proposed protocol outperforms mainstream used permissioned chain sharding protocols Attested HyperLedger and Sharper, achieving a throughput improvement of at least 20%. This protocol is suitable for scenarios requiring high throughput and reliability in industrial and commercial fields such as finance, logistics, and supply chain management. Even if the number of alliance chain nodes increases to the usual maximum, or there are some faulty nodes, the protocol can still maintain stable performance

    An Identity Privacy-Preserving Scheme against Insider Logistics Data Leakage Based on One-Time-Use Accounts

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    Digital transformation of the logistics industry triggered by the widespread use of Internet of Things (IoT) technology has prompted a significant revolution in logistics companies, further bringing huge dividends to society. However, the concurrent accelerated growth of logistics companies also significantly hinders the safeguarding of individual privacy. Digital identity has ascended to having the status of a prevalent privacy-protection solution, principally due to its efficacy in mitigating privacy compromises. However, the extant schemes fall short of addressing the issue of privacy breaches engendered by insider maleficence. This paper proposes an innovative identity privacy-preserving scheme aimed at addressing the quandary of internal data breaches. In this scheme, the identity provider furnishes one-time-use accounts for logistics users, thereby obviating the protracted retention of logistics data within the internal database. The scheme also employs ciphertext policy attribute-based encryption (CP-ABE) to encrypt address nodes, wherein the access privileges accorded to logistics companies are circumscribed. Therefore, internal logistics staff have to secure unequivocal authorization from users prior to accessing identity-specific data and privacy protection of user information is also concomitantly strengthened. Crucially, this scheme ameliorates internal privacy concerns, rendering it infeasible for internal interlopers to correlate the users’ authentic identities with their digital wallets. Finally, the effectiveness and reliability of the scheme are demonstrated through simulation experiments and discussions of security

    Altered hemispheric asymmetry of attentional networks in patients with pituitary adenoma: an event-related potential study

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    BackgroundEmerging evidence has been reported of attentional dysfunction in pituitary adenoma patients. However, the effect of pituitary adenomas on lateralized attention network efficiency remained to be clear. Thus, the present study aimed to investigate the impairment of lateralized attention networks in patients with pituitary adenoma.MethodsEighteen pituitary adenoma patients (PA group) and 20 healthy controls (HCs) were included in this study. Both behavioral results and event-related potentials (ERPs) were acquired while subjects performed the Lateralized Attention Network Test (LANT).ResultsBehavioral performances indicated the PA group had a slower reaction time and a similar error rate relative to the HCs group. Meanwhile, significantly increased executive control network efficiency suggested the dysfunction of inhibition control in PA patients. Regarding ERP results, there were no group differences in the alerting and orienting networks. The target-related P3 was significantly reduced in the PA group, suggesting an impairment of executive control function and attentional resources allocation. Moreover, the mean amplitude of P3 was significantly lateralized to the right hemisphere, and interacted with the visual field, exhibiting that the right hemisphere dominated the bilateral visual field, whereas the left hemisphere dominated the left visual field. In the specific high-conflict condition, the pattern of hemispheric asymmetry in the PA group was altered due to a mixed effect resulting from the compensatory recruitment of attentional resources in the left central parietal area and the destructive effects of hyperprolactinemia.ConclusionThese findings suggested that, in the lateralized condition, the decreased P3 in the right central parietal area and the diminished hemispheric asymmetry under high conflict load, may serve as the potential biomarkers of attentional dysfunction in patients with pituitary adenoma

    Location-Aware POI Recommendation for Indoor Space by Exploiting WiFi Logs

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    Indoor shopping trajectories provide us with a new approach to understanding user’s behaviour pattern in urban shopping mall, which can be derived from user-generated WiFi logs using indoor localization technology. In this paper, we propose a location-aware Point-of-Interest (POI) recommendation service in urban shopping mall that offers a user a set of indoor POIs by considering both personal interest and location preference. The POI recommendation service cannot only improve user’s shopping experience but also help the store owner better understand user’s shopping preference and intent. Specifically, the proposed method consists of two phases: offline modelling and online recommendation. The offline modelling phase is designed to learn user preference by mining his/her historical shopping trajectories. The online recommendation phase automatically produces top-k recommended POIs based on the learnt preference. To demonstrate the utility of our proposed approach, we have performed a comprehensive experiment evaluation on a real-world dataset collected by 468 users over 33 days. The experimental results show that the proposed recommendation service achieves much better recommendation performance than several existing benchmark methods

    TASG: An Augmented Classification Method for Impersonal HAR

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    Human activity recognition (HAR) systems are widely used in our lives, such as healthcare, security, and entertainment. Most of the activity recognition models are tested in the personal mode, and the performance is quite good. However, HAR in the impersonal mode is still a great challenge. In this paper, we propose a two-layer activity sparse grouping (TASG) model, in which the first layer clusters the activities into 2–4 groups roughly and the second layer identifies the specific type of activities. A new feature selection metric inspired by the Fisher criterion is designed to measure the importance of the features. We perform the experiment using the TASG model with SVM, KNN, Random Forest, and RNN, respectively. The experiments are tested on HAPT, MobiAct, and HASC-PAC2016 datasets. The experimental results show that the performance of standard classifiers has been improved while combining the TASG method. The features selected by the proposed metric are more effective than other FS methods

    Study on the cost attributable to central venous catheter-related bloodstream infection and its influencing factors in a tertiary hospital in China

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    Abstract Background Central venous catheters (CVC) have been widely used for patients with severe conditions. However, they increase the risk of catheter-related bloodstream infection (CRBSI), which is associated with high economic burden. Until now, no study has focused on the cost attributable to CRBSI in China, and data on its economic burden are unavailable. The aim of this study was to assess the cost attributable to CRBSI and its influencing factors. Methods A retrospective matched case-control study and multivariate analysis were conducted in a tertiary hospital, with 94 patients (age ≥ 18 years old) from January 2011 to November 2015. Patients with CRBSI were matched to those without CRBSI by age, principal diagnosis, and history of surgery. The difference in cost between the case group and control group during the hospitalization was calculated as the cost attributable to CRBSI, which included the total cost and five specific cost categories: drug, diagnostic imaging, laboratory testing, health care technical services, and medical material. The relation between the total cost attributable to CRBSI and its influencing factors such as demographic characteristics, diagnosis and treatment, and pathogenic microorganism, was analysed with a general linear model (GLM). Results The total cost attributable to CRBSI was 3528.6,andthecostsofspecificcategoriesincludingdrugs,diagnosticimaging,laboratorytesting,healthcaretechnicalservices,andmedicalmaterial,were3528.6, and the costs of specific categories including drugs, diagnostic imaging, laboratory testing, health care technical services, and medical material, were 2556.4, 112.1,112.1, 321.7, 268.7,268.7, 276.5, respectively. GLM analysis indicated that the total cost was associated with the intensive care unit (ICU), pathogenic microorganism, age, and catheter number, according to the sequence of standardized estimate (β). ICU contributed the most to the model R-square. Conclusion Central venous catheter–related bloodstream infection represents a great economic burden for patients. More attentions should be paid to further prevent and control this infection in China
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