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1.
Artigo em Inglês | MEDLINE | ID: mdl-37224353

RESUMO

In light of the dynamic plasticity, nanosize, and energy efficiency of memristors, memristive reservoirs have attracted increasing attention in diverse fields of research recently. However, limited by deterministic hardware implementation, hardware reservoir adaptation is hard to realize. Existing evolutionary algorithms for evolving reservoirs are not designed for hardware implementation. They often ignore the circuit scalability and feasibility of the memristive reservoirs. In this work, based on the reconfigurable memristive units (RMUs), we first propose an evolvable memristive reservoir circuit that is capable of adaptive evolution for varying tasks, where the configuration signals of memristor are evolved directly avoiding the device variance of the memristors. Second, considering the feasibility and scalability of memristive circuits, we propose a scalable algorithm for evolving the proposed reconfigurable memristive reservoir circuit, where the reservoir circuit will not only be valid according to the circuit laws but also has the sparse topology, alleviating the scalability issue and ensuring the circuit feasibility during the evolution. Finally, we apply our proposed scalable algorithm to evolve the reconfigurable memristive reservoir circuits for a wave generation task, six prediction tasks, and one classification task. Through experiments, the feasibility and superiority of our proposed evolvable memristive reservoir circuit are demonstrated.

2.
J Colloid Interface Sci ; 625: 197-209, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35716615

RESUMO

Conductive hydrogel-based flexible electronics have attracted immense interest in wearable sensor, soft robot and human-machine interface. However, the application of hydrogels in flexible electronics is limited by the deterioration of mechanical and electrical properties due to freezing at low temperature and desiccation after long-term use. Meanwhile, flexible electronics based on hydrogel are usually not breathable, which has a great impact on wearing comfort and signal stability in long-term sensing. In this work, an adjustable porous gelatin/polypyrrole/reduction graphene oxide (Gel/PPy/rGO) organohydrogel with high breathability (14 g∙cm-2∙h-1), conductivity (5.25 S/m), mechanical flexibility, anti-freezing and long-term stability is prepared via the combination method of biological fermentation and salt-out toughening crosslinking. The sensor fabricated from the prepared porous organohydrogel exhibits excellent sensing sensitivity, fast response ability, and good endurance, which monitors both weak and intense human activities effectively like finger bending, elbow bending, walking and running, and tiny pulse beating. A pressure sensor array prepared from the porous organohydrogel detects pressure variation in 2D sensitively. Furthermore, the porous organohydrogel is utilized as flexible electrodes for the accurate collection and recognition of human physiological signals (EMG, ECG) and as an interface between human and machine.


Assuntos
Polímeros , Dispositivos Eletrônicos Vestíveis , Condutividade Elétrica , Eletrônica , Gelatina , Grafite , Humanos , Hidrogéis , Porosidade , Pirróis
3.
Artigo em Inglês | MEDLINE | ID: mdl-35590475

RESUMO

Supermacroporous hydrogels have attracted wide concern due to their comfort and breathability in wearable health-monitoring applications. Size controllable supermacroporous structure and excellent mechanical properties are the most important for its application. However, they are normally fabricated by the cryogelation method, which is difficult to control pore size and maintain flexibility. Here, yeast fermentation-inspired gelatin hydrogels with a controllable supermacroporous structure and excellent mechanical properties were fabricated for the first time. The pore size can be controlled by adjusting the content of glucose and yeast, the ratio of glucose to yeast, fermentation time, and gelatin content during fermentation. The hydrogels demonstrated a controllable pore size range from 100 to 400 µm and rapid swelling characteristics. The mechanical properties were maintained by soaking ammonium sulfate solution for 12 h, showing maximum tensile and compressive strains over 300 and 99%, respectively. This novel approach can be easily applied to the preparation of supermacroporous and high ductility hydrogels under mild conditions. Furthermore, conductive hydrogels combined supermacroporous structures with conductive polyaniline and reduced oxidized graphene, and silver nanowires were prepared as wearable flexible sensors. The obtained sensors maintain well-distributed porosity, breathability, and mechanical flexibility, also showing excellent conductivity of 2.4 S m-1. Finally, the sensors were successfully applied to detect physiological signals and human-computer interaction.

4.
Sci Bull (Beijing) ; 66(22): 2312-2319, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34336365

RESUMO

The presence of antiphospholipid antibodies was shown to be associated with thrombosis in coronavirus disease 2019 (COVID-19) patients. Recently, according to reports from several studies, the vaccine-induced immune thrombotic thrombocytopenia is mediated by anti-platelet factor 4 (PF4)-polyanion complex in adenovirus-vectored COVID-19 vaccine recipients. It is impendent to explore whether inactivated COVID-19 vaccine widely used in China influences prothrombotic autoantibody production and induces thrombosis. In this prospective study, we recruited 406 healthcare workers who received two doses, 21 days apart, of inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine (BBIBP-CorV, Sinopharm). Paired blood samples taken before vaccination and four weeks after the second vaccination were used in detecting prothrombotic autoantibodies, including anticardiolipin (aCL), anti-ß2 glycoprotein I (aß2GP1), anti-phosphatidylserine/prothrombin (aPS/PT), and anti-PF4-heparin. The seroconversion rate of SARS-CoV-2 specific antibodies was 95.81% (389/406) four weeks after vaccination. None of the subjects had spontaneous thrombosis or thrombocytopenia over a minimum follow-up period of eight weeks. There was no significant difference in the presence of all ten autoantibodies between samples collected before and after vaccination: for aCL, IgG (7 vs. 8, P = 0.76), IgM (41 vs. 44, P = 0.73), IgA (4 vs. 4, P = 1.00); anti-ß2GP1, IgG (7 vs. 6, P = 0.78), IgM (6 vs. 5, P = 0.76), IgA (3 vs. 5, P = 0.72); aPS/PT IgG (0 vs. 0, P = 1.00), IgM (6 vs. 5, P = 0.76); aPF4-heparin (2 vs. 7, P = 0.18), and antinuclear antibody (ANA) (18 vs. 21, P = 0.62). Notably, seven cases presented with anti-PF4-heparin antibodies (range: 1.18-1.79 U/mL) after vaccination, and none of them exhibited any sign of thrombotic disorder. In conclusion, inactivated SARS-CoV-2 vaccine does not influence the profile of antiphospholipid antibody and anti-PF4-heparin antibody nor increase the risk of thrombosis.

5.
Langmuir ; 37(34): 10249-10258, 2021 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-34415769

RESUMO

In the present research, magnetically recyclable polyphosphazene (PCTP)/Ag (MPCTP-Ag) nanoparticles are prepared by a green path, in which PCTP was used to modify Fe3O4 nanoparticles and provide nucleation sites for the reduction of Ag nanoparticles. The prepared MPCTP-Ag nanoparticles were characterized by TEM, SEM, EDS, BET, XRD, vibrating sample magnometry, XPS, and TGA analysis. The catalytic performances of the MPCTP-Ag nanoparticles for the degradation of 4-nitrophenol (4-NP), methylene blue (MB), methyl orange (MO), and their mixtures in the presence of NaBH4 were studied. The main factors affecting the catalytic performance, including temperature, reactant concentration, and catalyst dosage, were investigated. The results showed that the MPCTP-Ag nanoparticles exhibited excellent catalytic activity for the degradation of all three targeted organic contaminants (4-NP, MB, and MO). Moreover, the product retains its catalytic activity after being reused five times by magnetic separation. The results showed that MPCTP-Ag composite nanoparticles were efficient recyclable magnetic nanocatalysts with promising application in environment protection.

6.
Clin Chem Lab Med ; 56(4): 614-624, 2018 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-29166262

RESUMO

BACKGROUND: The aim of the study was to determine the prevalence and clinical associations of antiphosphatidylserine/prothrombin antibodies (aPS/PT) with thrombosis and pregnancy loss in Chinese patients with antiphospholipid syndrome (APS) and seronegative APS (SNAPS). METHODS: One hundred and eighty six Chinese patients with APS (67 primary, 119 secondary), 48 with SNAPS, 176 disease controls (79 systemic lupus erythematosus [SLE], 29 Sjogren's syndrome [SS], 30 ankylosing spondylitis [AS], 38 rheumatoid arthritis [RA]) and 90 healthy donors were examined. IgG and IgM aPS/PT, IgG/IgM/IgA anticardiolipin (aCL) and IgG/IgM/IgA anti-ß2-glycoprotein I (anti-ß2GPI) antibodies were tested by ELISA. RESULTS: One hundred and sixty (86.0%) of APS patients were positive for at least one aPS/PT isotype. One hundred and thirty five (72.6%) were positive for IgG aPS/PT, 124/186 (66.7%) positive for IgM aPS/PT and 99 (53.2%) positive for both. Approximately half of the SNAPS patients were positive for IgG and/or IgM aPS/PT. Highly significant associations between IgG aPS/PT and venous thrombotic events (odds ratio [OR]=6.72) and IgG/IgM aPS/PT and pregnancy loss (OR=9.44) were found. Levels of IgM aPS/PT were significantly different in APS patients with thrombotic manifestations and those with fetal loss (p=0.014). The association between IgG/IgM aPS/PT and lupus anticoagulant (LAC) was highly significant (p<0.001). When both were positive, the OR for APS was 101.6. Notably, 91.95% (80/87) of LAC-positive specimens were positive for IgG and/or IgM aPS/PT, suggesting aPS/PT is an effective option when LAC testing is not available. CONCLUSIONS: Anti-PS/PT antibody assays demonstrated high diagnostic performance for Chinese patients with APS, detected some APS patients negative for criteria markers and may serve as potential risk predictors for venous thrombosis and obstetric complications.


Assuntos
Anticorpos Antifosfolipídeos/análise , Síndrome Antifosfolipídica/diagnóstico , Complicações do Trabalho de Parto/diagnóstico , Trombose Venosa/diagnóstico , Adulto , Anticorpos Antifosfolipídeos/imunologia , Síndrome Antifosfolipídica/epidemiologia , Síndrome Antifosfolipídica/imunologia , Biomarcadores/análise , China/epidemiologia , Feminino , Humanos , Masculino , Complicações do Trabalho de Parto/epidemiologia , Complicações do Trabalho de Parto/imunologia , Fosfatidilserinas/imunologia , Valor Preditivo dos Testes , Gravidez , Protrombina/imunologia , Fatores de Risco , Trombose Venosa/epidemiologia , Trombose Venosa/imunologia
7.
Clin Chem Lab Med ; 55(12): 1922-1930, 2017 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-28467309

RESUMO

BACKGROUND: Indirect immunofluorescence (IIF) assays are recommended as the gold standard method for the detection of antinuclear antibodies (ANAs). This study aimed to investigate the reliability of an automated system. METHODS: We compared 3745 serum samples using NOVA View archived images with manual analysis via microscopy. A custom cutoff value was established to distinguish ANA titers and was validated in two clinical laboratories. The automatic ANA pattern recognition system was evaluated, and all ANA-positive sera were subjected to two commercial ANA IIF kits to compare the consistency of the pattern interpretation results. For inconsistent patterns, a third ANA IIF testing kit was utilized. RESULTS: Agreement of the interpretation of the ANA IIF test using the platform of NOVA View and manual microscopy was 96.9%. The local cutoff value to discriminate ANA titers in four main ANA patterns was calculated based on 1390 serum samples. In our laboratory, the titer prediction accuracy was superior to the preset cutoff in NOVA View (p<0.01); the performance was similar in another laboratory (p=0.11). The automatic pattern recognition accuracies of speckled, homogeneous, centromere, nucleolar and nuclear dot patterns were 62.7%, 57.4%, 92.6%, 30.5% and 27.3%, respectively. The consistency of the pattern interpretation results between INOVA and MBL kits was 95.3%. CONCLUSIONS: It is necessary to establish a custom value-added ANA report. However, confirmation of the digital immunofluorescence images by expert technicians was essential, and suspect results of an ANA pattern should be reconfirmed by another commercial ANA IIF kit to achieve more reliable results.


Assuntos
Anticorpos Antinucleares/sangue , Automação/normas , Técnicas de Laboratório Clínico/normas , Doenças do Tecido Conjuntivo/sangue , Testes Diagnósticos de Rotina/normas , Técnica Indireta de Fluorescência para Anticorpo/normas , Doenças do Tecido Conjuntivo/diagnóstico , Humanos , Controle de Qualidade
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