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Purpose: In this study, specific measures adopted by the social media platforms in China supporting personal information management are investigated via surveys targeting such platforms. The purpose of this paper is to find out how social media platforms understand information management, and from which aspects and through what specific methods they provide support for information management, which contributes to understanding the issues and strategies associated with personal information management on social media. Design/methodology/approach: The dimensions and specific contents of the current platform support provided for information management are clearly defined by performing qualitative text analysis based on the content obtained from 11 platform policies published by five representative Chinese social media platforms. Findings: How social media platforms support personal information management on creation, collection, utilisation, sharing, storage, protection, removal and modification is identified. By analysing the status quo of support provided by the Chinese social media platform, some issues are proposed for discussion. Improved normative management is required to address the coexistence of multivalued information and management risks. However, the user rights are limited because the platform policies tend to be more focused on the perspective of the social media platform. Furthermore, the platform policy contents regarding information management are incomplete, and the applicability of these policies should be improved. Originality/value: This study seeks to contribute to personal information management on social media from the perspective of platform support. The perspective from the platforms as the service providers supporting information management also helps identify information management challenges and potential strategies. Furthermore, combining with the personal information management perspective, this study provides a background understanding of information management under a social collaborative framework for platforms, authorities, users and memory institutions. Peer review: The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-06-2020-0249 [ABSTRACT FROM AUTHOR]

In recent years, deep reinforcement learning (DRL) has proved its great potential in multi-agent cooperation. However, how to apply DRL to multi-target tracking (MTT) problem for unmanned aerial vehicle (UAV) swarms is challenging: 1) the scale of UAVs may be large, but the existing multi-agent reinforcement learning (MARL) methods that rely on global or joint information of all agents suffer from the dimensionality curse; 2) the dimension of each UAV's received information is variable, which is incompatible with the neural networks with fixed input dimensions; 3) the UAVs are homogeneous and interchangeable that each UAV's policy should be irrelevant to the permutation of its received information. To this end, we propose a DRL method for UAV swarms to solve the MTT problem. Firstly, a decentralized swarm-oriented Markov Decision Process (MDP) model is presented for UAV swarms, which involves each UAV's local communication and partial observation. Secondly, to achieve better scalability, a cartogram feature representation (FR) is proposed to integrate the variable-dimensional information set into a fixed-shape input variable, and the cartogram FR can also maintain the permutation irrelevance to the information. Then, the double deep Q-learning network with dueling architecture is adapted to the MTT problem, and the experience-sharing training mechanism is adopted to learn the shared cooperative policy for UAV swarms. Extensive experiments are provided and the results show that our method can successfully learn a cooperative tracking policy for UAV swarms and outperforms the baseline method in the tracking ratio and scalability. [ABSTRACT FROM AUTHOR]

This paper deals with the collaborative construction of private-natured yet social-oriented family archives by families, state archives and community management agencies. The construction of these archives has fostered an important practice model for national memory construction in China and can be used to build a base for education on patriotism and cultivation of fine family traditions. We conducted a case study on the Chen Yao Family Archives, the first social-oriented family archive in Sichuan Province. In this article we explore the methods of multi-actor collaborative construction and the specific contributions of different actors in terms of motives, contents and procedures. We also propose strategies for achieving successful construction of social-oriented family archives in terms of archival resources, multi-actor collaboration and utilization mechanisms. [ABSTRACT FROM AUTHOR]

Archiving in traditional villages has been carried out for nearly 20 years in China. The conventional practice is to establish registration records for the basic information and cultural heritage of traditional villages combined with collecting historical records. This research develops a digital archival model to strengthen traditional village conservation. The theoretical framework of this model arises from a case study of Gaoqian, a typical traditional Chinese village with 1000 years of history. Through field investigation and document analysis, Gaoqian's experience is summarized into a paradigm of traditional village digital archival conservation. There are three modules in this paradigm: a digital archival resource system, a digital archival management system, and a digital archival service system adhering to the culture-centred principle. This model transforms the initial cultural resources to digital archival resources and then to digital cultural products through strict life-cycle management. The whole working process needs the cooperation and participation of multiple subjects. The case of Gaoqian demonstrates that traditional village digital archival conservation is simultaneously universal and scene-oriented, which can provide replicable solutions for traditional villages or rural landscape conservation in other regions during ongoing world urbanization, with the appropriate archival perspective and methods. [ABSTRACT FROM AUTHOR]

The productive activation of CD4+ T lymphocytes, leading to proliferation and cytokine secretion, requires precise temporal regulation of intracellular cyclic AMP concentrations. The major effector molecule activated by cyclic AMP in mammalian cells is the cyclic AMP-dependent protein kinase A (PKA). The type I PKA isozyme mediates the inhibitory effects of cyclic AMP on T-cell activation. Using laser scanning confocal microscopy, we demonstrated that the regulation of PKA type I activity involves spatial redistribution of PKA type I molecules following T-cell receptor (TCR) stimulation. In resting T cells, PKA type I was located in membrane proximal regions and distributed equally across the cell. Shortly after antigen engagement, T cells and antigen-presenting cells formed an area of intense contact, known as the immunological synapse. TCR concentrated at the synapse, whereas PKA type I molecules redistributed to the opposite cell pole within 10 min after T-cell stimulation. Type I PKA redistribution was solely dependent on TCR signalling, because we observed the same temporal and spatial distribution after antibody-mediated cross-linking of the TCR-associated CD3 complex. Segregation of TCR and PKA type I molecules was maintained for at least 20 min. Thirty minutes after stimulation, PKA type I partially colocalized with the TCR. After 60 min, PKA type I distribution again approached the resting state. Considering that initial TCR signals lead to increases in intracellular cyclic AMP, PKA type I molecules may be targeted towards localized cyclic AMP accumulations or transported away from these areas, depending on the requirements of the cellular response. [ABSTRACT FROM AUTHOR]

CD4 is a coreceptor on T helper (Th) cells that interacts with MHC class II molecules (MHCII). The mechanisms mediating the effects of CD4 on responses by T helper cells to stimulation of the antigen-specific T cell receptor (TCR) are still poorly understood. Here, we demonstrate T cell costimulation via CD4 signalling independent of T cell receptor-mediated signals. Incubation of T helper cells with peptide mimetics of the CD4-binding region on the MHC class II β2 domain caused intracellular calcium mobilization in the absence of antigen or other T cell receptor stimuli. Engagement of CD4 by peptide mimetics or wild-type MHC class II, but not by mutant MHC class II molecules incapable of engaging CD4, inhibited the T cell receptor-mediated increase in cyclic AMP (cAMP) concentrations in T helper cells. CD4-mediated signals activated cyclic AMP phosphodiesterases (PDEs) and inhibited adenylyl cyclase. Full activation and clonal expansion of antigen-stimulated T helper cells required the CD4-mediated regulation of cyclic AMP. Our results suggest a costimulatory mechanism of CD4 function that acts on the second messengers, calcium and cyclic AMP. [Copyright &y& Elsevier]

Human pregnane X receptor (PXR) is critical for regulating the expression of key drug‐metabolizing enzymes such as CYP3A and CYP2C. Our recent study revealed that treatment with rodent‐specific PXR agonist pregnenolone‐16α‐carbonitrile (PCN) significantly induced hepatomegaly and promoted liver regeneration after two‐thirds partial hepatectomy (PHx) in mice. However, it remains unclear whether PXR activation induces hepatomegaly and liver regeneration and simultaneously promotes metabolic function of the liver. Here, we investigated the metabolism activity of CYP1A2, CYP3A1/2 and CYP2C6/11 during PXR activation‐induced liver enlargement and regeneration in rats after cocktail dosing of CYP probe drugs. For PCN‐induced hepatomegaly, a notable increase in the metabolic activity of CYP3A1/2 and CYP2C6/11, as evidenced by the plasma exposure of probe substrates and the AUC ratios of the characteristic metabolites to its corresponding probe substrates. The metabolic activity of CYP1A2, CYP3A1/2 and CYP2C6/11 decreased significantly after PHx. However, PCN treatment obviously enhanced the metabolic activity of CYP2C6/11 and CYP3A1/2 in PHx rats. Furthermore, the protein expression levels of CYP3A1/2 and CYP2C6/11 in liver were up‐regulated. Taken together, this study demonstrates that PXR activation not only induces hepatomegaly and liver regeneration in rats, but also promotes the protein expression and metabolic activity of the PXR downstream metabolizing enzymes such as CYP3A1/2 and CYP2C6/11 in the body. [ABSTRACT FROM AUTHOR]

Background/Aims: Breast cancer (BC) is the most common cancer in women worldwide. Despite great advancements in cancer therapy in recent years, surgery and chemotherapy are still the mainstays of BC treatment. However, cancer cells usually develop mechanisms to evade cell death induced by chemotherapy. Thus, strategies are needed to reverse the chemoresistance of cancer cells. Methods: We established cisplatin-resistant BC models in MDA-MB-231 and MCF-7 BC cell lines through long-term exposure to cisplatin. Quantitative reverse transcription PCR was used to examine the expression of microRNA (miR)-100. MTT cell viability assays were performed to determine cell viability. Regulation of hematopoietic cell-specific protein 1-associated protein X-l (HAX-1) targeted by miR-100 was confirmed by western blotting and luciferase reporter assays. The mitochondrial membrane potential and apoptosis were measured by flow cytometry. Release of cytochrome c from the mitochondria into the cytoplasm, HAX-1 expression, and activation of caspase-9 and caspase-3 were detected by western blotting. Results: A clear decrease in miR-100 expression was observed in cisplatin-resistant MDA-MB-231 and MCF-7 cells (MDA-MB-231/R and MCF-7/R). Overexpression of miR-100 increased the sensitivity of MDA-MB-231/R and MCF-7/R cells to cisplatin treatment and promoted cisplatin-induced mitochondrial apoptosis by targeting HAX-1 gene. Conclusions: MiR-100 targeted HAX-1 to increase the chemosensitivity of BC by mediating the mitochondrial apoptosis pathway. [ABSTRACT FROM AUTHOR]

• A LWIR 1280 × 1024 FPA with a pitch of 10 μm based on InAs/GaSb superlattice was demonstrated. • A long wavelength supperlattice material with low dark current density and high material uniformity was obtained. • A LWIR 1280 × 1024 FPA with low NETD, low operability and high non-uniformity was obtained. 1280 × 1024 format long-wavelength infrared focal plane array with 10 μm pixel pitch was fabricated based on InAs/GaSb type-II superlattice. At 70 K, the single-element device shows a 50% cutoff wavelength of 10.0 μm, peak quantum efficiency of 45.04% and peak detectivity of 1.87 × 1011cm·Hz1/2·W−1 at 8.22 μm, the FPA infrared imaging performed an average noise equivalent temperature difference of 28.9 mK at 300 K background (F/3 optics) with an integration time of 1.12 ms and applied bias of −50 mV. The operability and non-uniformity of the FPA were 99.87% and 2.90% respectively, and it exhibits a stable residual non-uniformity below 0.1% of the dynamic range. [ABSTRACT FROM AUTHOR]

Background/Aims: To assess the prognostic accuracy of absolute serum creatinine (sCr) changes ('Delta-sCr') on the long-term outcomes in cirrhotic patients, and evaluate the performance of the 'Delta-sCr' approach to stage acute kidney injury (AKI), compared with the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Methods: We conducted a retrospective analysis of 333 hospitalized patients. We classified AKI stages using two methods: 1) KDIGO AKI criteria; 2) 'Delta-sCr' system, defined by the difference between the baseline and the peak sCr value during the hospitalization. The end point was the hazard of 1-year death. Results: The prevalence of AKI in cirrhotic patients was 18.01% by the KDIGO criteria, and 25.22% by the 'Delta-sCr' system. On multivariable Cox hazard analysis, both of the two methods were independent predictive factors of death ('Delta-sCr' system: OR=2.911, p<0.001), (KDIGO criteria: OR=2.065, p<0.001). However, the 'Delta-sCr' system provided a modest improvement in classification over the KDIGO criteria with a net reclassification improvement (NRI) of 28.7% (p<0.001) and integrated discrimination improvement (IDI) of 7.5% (p=0.03). And the predictive value of the 'Delta-sCr' system could be significantly improved (p=0.006), when combined with age and MELD score. Conclusion: The Delta-sCr is associated with the 1-year mortality. And the 'Delta-sCr' system may optimize the discrimination of risk prediction. [ABSTRACT FROM AUTHOR]

Aim Chronic hepatitis B-associated liver failure (CHB-LF) is associated with high mortality. Antiviral therapy with nucleoside and nucleotide analogs (NUCs) has been reported to improve the short-term prognosis of patients with CHB-LF. However, the long-term effects of the therapy remain unclear. We undertook a cohort study to investigate the long-term effect of NUC-based antiviral therapy in patients with CHB-LF. Methods A total of 976 patients with CHB-LF were enrolled between January 2001 and December 2009 at the Liver Disease Center of Ningbo No. 2 Hospital (Ningbo, China). The patients were divided into the NUC treatment group ( n = 412) and control group ( n = 564). The propensity score matching method was used to match the patients between the two groups to equilibrate the covariates. Survival analysis was carried out using the matched samples. The Cox proportional hazard model was used for the analysis of prognostic factors. Results After propensity matching, 262 pairs were successfully matched. No statistically significant difference was observed in the baseline characteristics of the matching pairs ( P > 0.05). The long-term survival rate and survival duration of the NUC treatment group were higher than that of the control group ( P < 0.05). Gender, age, Model for End-stage Liver Disease values, cholinesterase levels, white blood cell counts, hepatic encephalopathy, concomitant infection, and treatment with NUCs were found to be the independent factors associated with long-term prognosis. Conclusion Antiviral therapy with NUCs may reduce the mortality rate and improve the long-term prognosis of patients with CHB-LF. [ABSTRACT FROM AUTHOR]

A simple procedure for the synthesis of three new oxazolinyl-substituted β-cyclodextrins (6-deoxy-6- R-(-)-4-phenyl-4,5-dihydrooxazolinyl-β-cyclodextrin, 6-deoxy-6- S-(-)-4-phenyl-4,5-dihydrooxazolinyl-β-cyclodextrin, and 6-deoxy-6- S-(-)-(4-pyridin-1-ium-4-methyl-benzenesulphonate)-4,5-dihy-drooxazolinyl-β-cyclodextrin) and their covalent bonding to silica are reported. The ability of these chiral stationary phase columns for separating compounds is also presented and discussed. Twenty-eight compounds were examined in the polar-organic mobile phase mode, and 11 β-nitroethanols were tested in the reversed-phase mode. Excellent enantioseparations were achieved for most of the analytes, even for several challenging compounds. The rigid and flexible structures of mono-substituted chiral groups and the fragments around the rim of the β-cyclodextrin cavity played an important role in the separation process. Factors such as π-π stacking, dipole-dipole interactions, ion-pairing, and steric hindrance effects were found to affect the chromatographic performance. Moreover, the buffer composition, and percentages of organic modifiers in the mobile phase, were investigated and compared. The mechanisms involved in the separation were postulated based on the chromatographic data. [ABSTRACT FROM AUTHOR]

Abstract: A novel chiral selector mono-6-deoxy-(2,4-dihydroxybenzimide)-β-CD (MDHB-β-CD) in which the derivatized group and the cavity of CD is linked by CH2–Nwas successfully prepared, and the structural characteristics were determined by FT-IR, 1H and 13C NMR, MALDITOF-MS and element analysis. The corresponding stationary phase (CSP) was used in HPLC and the enantioseparation performance was investigated using chiral 1-phenyl-2-nitroethanol derivatives as test samples in the reverse-phase mode composed of methanol/water and acetonitrile/TEAA. Better separation abilities and excellent enantioselectivities (α >1.26, R S >1.73) were obtained on MDHB-β-CD CSP for these chiral compounds in the methanol/water mobile phase. [Copyright &y& Elsevier]

• T2SL photodetectors with deep and vertical sidewalls were prepared. • High-performance ALD-Al 2 O 3 with TMA and H 2 plasma combined pretreatment was achieved. • Surface leakage was effectively suppressed by TMA and H 2 plasma combined pretreatment. • The surface pretreatment effects and dark current mechanisms were studied in detail. For type-II InAs/GaSb superlattice (T2SL) photodetectors with deep and vertical mesa sidewalls, passivation for suppression of surface leakage currents is facing two key challenges that in the conformal coating of sharp sidewalls and increasing dominance of surface leakage currents as device dimensions shrink. In this work, atomic layer deposited (ALD)-Al 2 O 3 and SiO 2 method was employed as conformal passivation for deep and vertical mesa sidewalls. And a stable and high-quality interface between the ALD-Al 2 O 3 and T2SL mesa sidewalls was obtained by the combined pretreatment of trimethylaluminum (TMA) and H 2 plasma exposure (Al 2 O 3 TH), and thus a significant improvement in electrical performances has been achieved. The electrical performances before and after baking were compared among the Al 2 O 3 TH, conventional sulfur plus SiO 2 passivated photodiodes. The dark current density of Al 2 O 3 TH passivated photodiodes were improved by 81% at 77 K under 0.1 V reverse bias and exhibited no deterioration after 90 °C-4 days baking treatment. Investigation on the effects of TMA and/or H 2 plasma pretreatments demonstrates that combined pretreatment of TMA and H 2 plasma, rather than TMA or H 2 plasma alone, prior to the deposition of ALD-Al 2 O 3 leads to a more thorough elimination of interface native oxides and surface states introduced in mesa process. The innovative application of this effective surface pretreatment technique is very encouraging for the passivation of deep and vertical sidewalls in III-V compound-based devices, such as large-format T2SL infrared detectors. [ABSTRACT FROM AUTHOR]