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Inspired by the 2D bilayer lipid membranes in nature, a unique supramolecular "push-pull" synergetic strategy toward self-assembled 2D organic crystals (2DOCs) is proposed in this work, which can effectively suppress the interlayer 3D stacking while maintaining the assembly of the intralayer for 2D growth. For this purpose, a model molecule PF-Py consisting of a planar supramolecular "attractor" and a nonplanar steric "repellor" is designed for the solution self-assembly process. Well-defined 2DOCs including crystal nanosheets and millimeter-sized crystal films with layered amphiphile-like packing are obtained, which is analogical to the cell membranes of living organisms. Thanks to the special packing mode, the 2DOCs have fascinating integrated photoelectric property, with high mobility of 7.8 × 10-2 cm2 V-1 s-1 , high crystalline state photoluminescence quantum yield of 55%, and superior deep-blue laser characteristics with a low threshold of 5.51 µJ cm-2 . This supramolecular synergetic strategy advances the design of 2D organic semiconductor crystals for high performance optoelectronics.
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SemiconductoresRESUMEN
[This corrects the article DOI: 10.3389/fbioe.2022.890132.].
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OBJECTIVE: To investigate the effect of phorbol-12-myristate-13-ace-tate (TPA) on the proliferation and apoptosis of acute promyelocytic leukemia cell line NB4 and its molecular mechanism. METHODS: The effect of different concentrations of TPA on the proliferation of NB4 cells at different time points was detected by CCK-8 assay. The morphological changes of NB4 cells were observed by Wright-Giemsa staining. The cell cycle and apoptosis of NB4 cells after TPA treatment were detected by flow cytometry. The mRNA expressions of NB4 cells after TPA treatment were analyzed by high-throughput microarray analysis and real-time quantitative PCR. Western blot was used to detect the protein expression of CDKN1A, CDKN1B, CCND1, MYC, Bax, Bcl-2, c-Caspase 3, c-Caspase 9, PIK3R6, AKT and p-AKT. RESULTS: Compared with the control group, TPA could inhibit the proliferation of NB4 cells, induce the cells to become mature granulocyte-monocyte differentiation, and also induce cell G1 phase arrest and apoptosis. Differentially expressed mRNAs were significantly enriched in PI3K/AKT pathway. TPA treatment could increase the mRNA levels of CCND1, CCNA1, and CDKN1A, while decrease the mRNA level of MYC. It could also up-regulate the protein levels of CDKN1A, CDKN1B, CCND1, Bax, c-Caspase 3, c-Caspase 9, and PIK3R6, while down-regulate MYC, Bcl-2, and p-AKT in NB4 cells. CONCLUSION: TPA induces NB4 cell cycle arrest in G1 phase and promotes its apoptosis by regulating PIK3/AKT signaling pathway.
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Leucemia Promielocítica Aguda , Humanos , Caspasa 3/metabolismo , Caspasa 9/genética , Caspasa 9/metabolismo , Caspasa 9/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Línea Celular Tumoral , División Celular , Apoptosis , ARN Mensajero , Proliferación CelularRESUMEN
OBJECTIVE: To investigate and analyze the occupational hazards of ultraviolet radiation, protective measures and related factors for typical symptoms among workers in electric welding, and to provide basic information for revision of the occupational standards of UV. METHODS: Questionnaires and physical examinations were used in this investigation. A total of 828 workers from four vehicle manufacturers in Beijing and Guangdong Province were selected. Corresponding analyses were conducted with SPSS 16.0 statistic software. RESULTS: The top three injuries of faces and hands were burning tingling (48.7% & 41.3%), itch of skin (39% & 34.9%) and pigmentation (31.9% & 24.5%).The major injuries of eyes were ophthalmodynia (61.5%) , photophobia and tearing (61.4%), and blurred vision (50.2%). The incidences of facial and hands burning tingling, hands flushing, hands macula and papula were significantly different between the welders and auxiliary workers (P<0.05). The differences of facial and hands burning tingling, flushing, facial disesthesia and anaesthesia, symptoms and signs of eyes were significant in different working years groups (P<0.05). The top three usages of protective measures were welding masks (87.2%), gloves (84.3%) and glasses (65.9%). Except for UV cut cream, the usages of other protective equipments in the auxiliary workers were significantly lower than those in the welders (P<0.05). The logistic regression analysis showed that prolonged exposure to arc welding, using argon arc welding and CO(2) gas shielded arc welding, not wearing welding masks, and not using UV cut cream was significantly associated with the increased risk of face burning tingling, and the ORs were 3.894 (6 h to 8 h), 2.665 (4 h to 6 h), 2.052, 1.765, 1.759, 1.833, respectively; working years might be a protective factor, and the OR was 0.440, respectively. CONCLUSION: The study suggested that the UV radiation produced during welding operations not only caused harm to welders, but also to the auxiliary workers. Protection should be strengthened,for example, wearing welding masks, glasses, etc. Meanwhile automatic welding machines should be adopted by the factories to reduce the exposure time for workers.
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Exposición Profesional/efectos adversos , Traumatismos por Radiación/prevención & control , Rayos Ultravioleta/efectos adversos , Soldadura , Adolescente , Adulto , Automóviles , China , Femenino , Humanos , Industrias , Masculino , Persona de Mediana Edad , Traumatismos por Radiación/etiología , Protección Radiológica/métodos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
When the human brain learns multiple related or continuous tasks, it will produce knowledge sharing and transfer. Thus, fast and effective task learning can be realized. This idea leads to multi-task learning. The key of multi-task learning is to find the correlation between tasks and establish a fast and effective model based on these relationship information. This paper proposes a multi-task learning framework based on stochastic configuration networks. It organically combines the idea of the classical parameter sharing multi-task learning with that of constraint sharing configuration in stochastic configuration networks. It organically combines the idea of the classical parameter sharing multi-task learning with that of constraint sharing configuration in stochastic configuration neural networks. Moreover, it provides an efficient multi-kernel function selection mechanism. The convergence of the proposed algorithm is proved theoretically. The experiment results on one simulation data set and four real life data sets verify the effectiveness of the proposed algorithm.
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Neuromorphic electronics, which use artificial photosensitive synapses, can emulate biological nervous systems with in-memory sensing and computing abilities. Benefiting from multiple intra/interactions and strong light-matter coupling, two-dimensional heterostructures are promising synaptic materials for photonic synapses. Two primary strategies, including chemical vapor deposition and physical stacking, have been developed for layered heterostructures, but large-scale growth control over wet-chemical synthesis with comprehensive efficiency remains elusive. Here we demonstrate an interfacial coassembly heterobilayer films from perylene and graphene oxide (GO) precursors, which are spontaneously formed at the interface, with uniform bilayer structure of single-crystal perylene and well-stacked GO over centimeters in size. The planar heterostructure device exhibits an ultrahigh specific detectivity of 3.1 × 1013 Jones and ultralow energy consumption of 10-9 W as well as broadband photoperception from 365 to 1550 nm. Moreover, the device shows outstanding photonic synaptic behaviors with a paired-pulse facilitation (PPF) index of 214% in neuroplasticity, the heterosynapse array has the capability of information reinforcement learning and recognition.
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Grafito , Perileno , Plasticidad Neuronal , Sinapsis/fisiologíaRESUMEN
OBJECTIVE: To investigate and analyze present conditions of the assembling line illumination in our country, and to set the recommended values of illuminance standard. METHODS: Questionnaires and field surveys were used in this investigation. A total of 752 workers from seven factories in textile, shoes and electronics industries were selected for the questionnaire survey and site measurement, and corresponding analyses made with SPSS 13.0 statistic software. RESULTS: Uniformity of illumination, definition in working face, general satisfactory degrees, asthenopia were significantly correlated with each other. Assembly line illuminances for five different visual characteristics were recommended in this paper. The illuminances were 500-1 000-1 500 lx, 300-500-1 000 lx, 200-300-750 lx, 100-300-500 lx, 50-100-200 lx, respectively. CONCLUSION: Present conditions of the assembling line illumination are less than satisfactory, uniformity of illumination is on the low side, and there is no assembling line illuminance standard for general satisfactory degrees and asthenopia of workers. The related work should be further improved.
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Industrias , Iluminación/normas , Salud Laboral , Trastornos de la Visión/prevención & control , Lugar de Trabajo , Adulto , China , Electrónica , Femenino , Humanos , Masculino , Zapatos , Encuestas y Cuestionarios , Industria TextilRESUMEN
OBJECTIVE: To investigate the interactive effect of job task and psychosocial factors on the outcomes of musculoskeletal disorders. METHODS: 653 workers from different type of manufacturing industries and administration office recruited in a cross-sectional epidemiological survey. The Quick Exposure Check (QEC) was applied to assess the ergonomic load of job task, Job Content Questionnaire (JCQ) for identifying psychological characteristics, and Nordic Standardized Questionnaire for investigating outcomes of WMSDs. RESULTS: The prevalence of WMSD in shoulder, upper back, lower back and hand/wrist were significantly different under a variety of combined job task and psychosocial characteristics (P < 0.05 or P < 0.01). The more physical and psychological loads, the higher prevalence of WMSDs were revealed. By using multivariate analyses, a potential interactive effect was found in terms of the WMSDs symptoms in hand/wrist, shoulder, upper back and lower back after adjusted by work year, age, and gender. CONCLUSIONS: Higher physical load and greater psychosocial risk are more frequent self-reported symptoms of WMSDs than those of lower exposures. Ergonomic intervention strategies aimed at reducing the incidence of WMSDs should not only be focused on control of physical work factors but also psychosocial risks of relevance.
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Enfermedades Musculoesqueléticas/etiología , Enfermedades Musculoesqueléticas/psicología , Enfermedades Profesionales/etiología , Enfermedades Profesionales/psicología , Estrés Psicológico , Análisis y Desempeño de Tareas , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Two spirocyclic aromatic hydrocarbon derivatives were prepared to clarify the molecular geometry effects on the regulation of the crystalline morphologies and photophysical behaviors of organic nanocrystals. Due to the different structural symmetry of a spiro-center, distinguishing nanocrystal morphologies with unique crystallization-enhanced/quenched emission was achieved.
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OBJECTIVE: To evaluate the effects of Xuefu Zhuyu Decoction (XFZYD) on functions of vascular endothelium in patients with unstable angina pectoris (UAP). METHODS: Fifty patients with UAP were randomly divided into two groups: XFZYD-treated group with 32 cases and control group with 18 cases. The patients in the control group were given regular therapy, while the patients in the XFZYD-treated group were given XFZYD additionally on the basis of regular therapy. All patients in both groups were treated for 8 weeks. Then the contents of serum endothelin (ET), nitric oxide (NO), soluble vascular cell adhesive molecule-1 (sVCAM-1) and soluble intercellular adhesion molecule-1 (sICAM-1) were examined by radioimmunoassay, enzymic method and enzyme-linked immunosorbent assay (ELISA) respectively. RESULTS: The total response rate in the XFZYD-treated group was 93.75%, which was significantly higher than 66.67% in the control group (P<0.05). The contents of serum ET, sVCAM-1 and sICAM-1 in the XFZYD-treated group were much lower than those in the control group (P<0.01), while the content of serum NO was obviously higher than that in the control group (P<0.01). CONCLUSION: XFZYD can improve the functions of vascular endothelium by lowering the levels of endothelium-derived contracting substances, enhancing the levels of endothelium-derived relaxing substances, and reducing the cell adhesions, and hence to raise the therapeutic effects on UAP.