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1.
J Hazard Mater ; 401: 123865, 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33113751

RESUMO

The life cycle impacts of treatment of typical oil-based drill cuttings (OBDCs) using three low-temperature thermal desorption (LTTD)-based systems, including thermomechanical cuttings cleaner (TCC), screw-type dryer (STD), and rotary drum dryer (RDD), were explored with a case study in British Columbia, Canada. Two energy supply scenarios, including diesel generator-based onsite (scenario i) and hydropower-based offsite (scenario ii) treatments, were considered in the assessment. The results show that RDD generated the lowest life cycle impacts in terms of damages to human health, ecosystems, and resources in scenario i. TCC-scenario ii generated the lowest impacts among all assessed cases, suggesting that using renewable energy can greatly reduce the impacts of LTTD-based OBDCs treatment. Also, net environmental benefits could be achieved considering the reuse of recovered oil, and the highest net environmental benefits were obtained in TCC-scenario ii. The process contribution analysis found that thermal desorption process accounted for 80-95 % of impacts in almost all impact categories. Energy consumption contours and linear regression models were also developed to help drilling waste managers estimate the life cycle impacts of using hydropower-driven TCC to treat OBDCs with different water and oil contents.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33139545

RESUMO

Horseback riding was a transformative force in the ancient world, prompting radical shifts in human mobility, warfare, trade, and interaction. In China, domestic horses laid the foundation for trade, communication, and state infrastructure along the ancient Silk Road, while also stimulating key military, social, and political changes in Chinese society. Nonetheless, the emergence and adoption of mounted horseback riding in China is still poorly understood, particularly due to a lack of direct archaeological data. Here we present a detailed osteological study of eight horse skeletons dated to ca. 350 BCE from the sites of Shirenzigou and Xigou in Xinjiang, northwest China, prior to the formalization of Silk Road trade across this key region. Our analyses reveal characteristic osteological changes associated with equestrian practices on all specimens. Alongside other relevant archaeological evidence, these data provide direct evidence for mounted horseback riding, horse equipment, and mounted archery in northwest China by the late first millennium BCE. Most importantly, our results suggest that this region may have played a crucial role in the spread of equestrian technologies from the Eurasian interior to the settled civilizations of early China, where horses facilitated the rise of the first united Chinese empires and the emergence of transcontinental trade networks.

4.
Stroke Vasc Neurol ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154178

RESUMO

BACKGROUND AND PURPOSE: The Trial of Org 10 172 in Acute Stroke Treatment (TOAST) system is the most widely used aetiological categorisation system in clinical practice and research. Limited studies have validated the accuracy of routine aetiological diagnosis of patients with ischaemic stroke according to the TOAST criteria when the reported subtype is assumed to be correct. We investigated the agreement between centralised and non-centralised (site-reported, at discharge) stroke subtypes in the Third China National Stroke Registry (CNSR-III), and analysed the influence of classification consistency on evaluation during hospitalisation and for secondary prevention strategy. METHODS: All patients with ischaemic stroke from the CNSR-III study with complete diffusion-weighted imaging data were included. We used multivariable Cox proportional-hazard regression models to evaluate the factors associated with consistency between centralised and non-centralised stroke subtypes. Sensitivity analyses were conducted of the subgroup of patients with complete information. RESULTS: This study included 12 180 patients (mean age, 62.3 years; and women, 31.4%). Agreement between centralised and non-centralised subtype was the highest for the large-artery atherosclerosis subtype stroke (77.4% of centralised patients), followed by the small-vessel occlusion subtype (40.6% of centralised patients). Agreements for cardioembolism and stroke of other determined aetiology subtypes were 38.7% and 12.2%, respectively. Patient-level and hospital-level factors were associated with the inconsistency between centralised/non-centralised aetiological subtyping. This inconsistency was related to differences in secondary prevention strategies. Only 15.3% of the newly diagnosed patients with cardioembolism underwent centralised subtyping with indications to receive oral anticoagulants at discharge. In comparison, 51.3% of the consistent cardioembolism group and 42.0% of the centrally reassigned cardioembolism group with anticoagulation indications were prescribed oral anticoagulants. CONCLUSIONS: Substantial inconsistency exists between centralised and non-centralised subtyping in China. Inaccurate aetiological subtyping could lead to inadequate secondary prevention, especially in patients with cardioembolic stroke.

5.
Korean J Radiol ; 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33169546

RESUMO

OBJECTIVE: To determine whether noncontrast computed tomography (NCCT) models based on multivariable, radiomics features, and machine learning (ML) algorithms could further improve the discrimination of early hematoma expansion (HE) in patients with spontaneous intracerebral hemorrhage (sICH). MATERIALS AND METHODS: We retrospectively reviewed 261 patients with sICH who underwent initial NCCT within 6 hours of ictus and follow-up CT within 24 hours after initial NCCT, between April 2011 and March 2019. The clinical characteristics, imaging signs and radiomics features extracted from the initial NCCT images were used to construct models to discriminate early HE. A clinical-radiologic model was constructed using a multivariate logistic regression (LR) analysis. Radiomics models, a radiomics-radiologic model, and a combined model were constructed in the training cohort (n = 182) and independently verified in the validation cohort (n = 79). Receiver operating characteristic analysis and the area under the curve (AUC) were used to evaluate the discriminative power. RESULTS: The AUC of the clinical-radiologic model for discriminating early HE was 0.766. The AUCs of the radiomics model for discriminating early HE built using the LR algorithm in the training and validation cohorts were 0.926 and 0.850, respectively. The AUCs of the radiomics-radiologic model in the training and validation cohorts were 0.946 and 0.867, respectively. The AUCs of the combined model in the training and validation cohorts were 0.960 and 0.867, respectively. CONCLUSION: NCCT models based on multivariable, radiomics features and ML algorithm could improve the discrimination of early HE. The combined model was the best recommended model to identify sICH patients at risk of early HE.

6.
Respir Res ; 21(1): 287, 2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33129326

RESUMO

BACKGROUND: Under physiological conditions, CXCL12 modulates cell proliferation, survival, angiogenesis, and migration mainly through CXCR4. Interestingly, the newly discovered receptor CXCR7 for CXCL12 is highly expressed in many tumor cells as well as tumor-associated blood vessels, although the level of CXCR7 in normal cells is low. Recently, many studies have suggested that CXCR7 promotes cell growth and metastasis in more than 20 human malignancies, among which lung cancer is the leading cause of cancer-associated deaths worldwide. Thus, the mechanism of CXCR7 in the progression of lung cancer is urgently needed. METHODS: First, we explored CXCR4 and CXCR7 expression in human lung cancer specimens and cell lines by immunohistochemistry, western blot and flow cytometry. Then, we chose the human lung adenocarcinoma cell line A549 that stably overexpressed CXCR7 through the way of lentivirus-mediated transduction. Next, "wound healing" assay and transwell assay were applied to compare the cell migration and invasion ability, and stripe assay was used to evaluate the cell polarization. Last, our team established a mouse xenograft model of human lung cancer and monitored tumor proliferation and metastasis by firefly luciferase bioluminescence imaging in SCID/Beige mice. RESULTS: In clinical lung cancer samples, CXCR7 expression was almost not detected in normal tissue but upregulated in lung tumor tissue, whereas, CXCR4 was highly expressed in both normal and tumor tissues. Furthermore, overexpression of CXCR7 enhanced A549 cell migration and polarization in vitro. Besides, mouse xenograft model of human lung cancer showed that CXCR7 promoted primary lung tumor's growth and metastasis to the second organ, such as liver or bone marrow in SCID/Beige mice in vivo. CONCLUSIONS: This study describes the multiple functions of CXCR7 in lung cancer. Thus, these results suggest that CXCR7 may be a malignancy marker and may provide a novel target for anticancer therapy.

7.
Life Sci ; : 118688, 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33130074

RESUMO

AIMS: Many gastrointestinal (GI) disorders are developmental in origin and are caused by abnormal enteric nervous system (ENS) formation. Maternal vitamin A deficiency (VAD) during pregnancy affects multiple central nervous system developmental processes during embryogenesis and fetal life. Here, we evaluated whether maternal diet-induced VAD during pregnancy alone can cause changes in the ENS that lead to GI dysfunction in rat offspring. MAIN METHODS: Rats were selected to construct animal models of normal VA, VA deficiency and VA supplementation. The fecal water content, total gastrointestinal transmission time and colonic motility were measured to evaluate gastrointestinal function of eight-week-old offspring rats. The expression levels of RARß, SOX10, cholinergic (ChAT) and nitrergic (nNOS) enteric neurons in colon tissues were detected through western blot and immunofluorescence. Primary enteric neurospheres were treated with retinoic acid (RA), infection with Ad-RARß and siRARß adenovirus, respectively. KEY FINDINGS: Our data revealed marked reductions in the mean densities of cholinergic and nitrergic enteric neurons in the colon and GI dysfunction evidenced by mild intestinal flatulence, increased fecal water content, prolonged total GI transit time and reduced colon motility in adult offspring of the VAD group. Interestingly, maternal VA supplementation (VAS) during pregnancy rescued these changes. In addition, in vitro experiments demonstrated that exposure to appropriate doses of RA promoted enteric neurosphere differentiation into cholinergic and nitrergic neurons, possibly by upregulating RARß expression, leading to enhanced SOX10 expression. SIGNIFICANCE: Maternal VAD during pregnancy is an environmental risk factor for GI dysfunction in rat offspring.

8.
J Neuroimmunol ; 350: 577438, 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33197842

RESUMO

Neurological complications are very common after liver transplantation. This study focuses on clinical risk factors and susceptibility gene polymorphisms of neurological complications after liver transplantation. A better predictive model is obtained. This study proves that MTRR is an independent susceptibility gene for neurological complications. Compared with the independent risk factor of abdominal infection, MTRR has a more advantageous value in predicting neurological complications after liver transplantation.

9.
Sci Total Environ ; : 143295, 2020 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-33183811

RESUMO

An emission inventory of precursors is a prerequisite for the simulation of secondary organic aerosol (SOA), which could provide valuable information on the evolution of precursors, formation of SOA, and its influence on fine particle (PM2.5) abundance, oxidative capacity, and climate change. However, an emission inventory of semi-volatile and intermediate volatility organic compounds (S/IVOCs), the key precursor of SOA, particularly the gridded inventory that is appropriate for input into regional air quality models, remains limited in China, leading to an incomplete understanding of S/IVOCs sources and roles in SOA formation and the atmospheric environment. Therefore, a gridded emission inventory of S/IVOCs in China for 2016 was developed based on ample source-specific measured data on emission ratios of S/IVOCs to primary organic aerosols (POA) from literatures. The total emission of S/IVOCs was estimated to be 9.6 Tg, and industry and residential sectors were major sources of S/IVOCs, with contributions of 48.0% and 30.2%, respectively. The spatial variations suggested that S/IVOC emissions were mainly distributed in the highly industrialized and urbanized regions in China, such as Beijing-Tianjin-Hebei (BTH), the Yangtze River Delta (YRD), the Pearl River Delta (PRD), and the Sichuan-Chongqing (SC) regions, though the contributions and temporal patterns varied between different regions. Furthermore, uncertainty of the emission inventory was estimated to be within the range of -66%-153%, which was mainly attributed to emission ratios of IVOCs/POA for industry, transportation, and power plants. The gridded emission inventory developed in this study can be used to estimate the emissions of S/IVOCs in different regions, and can be applied to different models for a better understanding of the environmental effects of S/IVOCs.

10.
Stem Cells ; 2020 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-33159702

RESUMO

Mouse dental papilla cells (mDPCs) derive from cranial neural crest cells and maintain mesenchymal stem cell characteristics. The differentiation of neural crest cells into odontoblasts is orchestrated by transcription factors regulating the expression of genes whose enhancers are initially inaccessible. However, the identity of the transcription factors driving the emergence of odontoblast lineages remains elusive. In this study, we identified SALL1, a transcription factor that was particularly expressed in preodontoblasts, polarizing odontoblasts, and secretory odontoblasts in vivo. Knockdown of Sall1 in mDPCs inhibited their odontoblastic differentiation. In order to identify the regulatory network of Sall1, RNA sequencing and an assay for transposase-accessible chromatin with high-throughput sequencing were performed to analyze the genome-wide direct regulatory targets of SALL1. We found that inhibition of Sall1 expression could decrease the accessibility of some chromatin regions associated with odontoblast lineages at embryonic day 16.5, whereas these regions remained unaffected at postnatal day 0.5, suggesting that SALL1 regulates the fate of mDPCs by remodeling open chromatin regions at the early bell stage. Specifically, we found that SALL1 could directly increase the accessibility of cis-regulatory elements near Tgf-ß2 and within the Runx2 locus. Moreover, coimmunoprecipitation and proximal ligation assays showed that SALL1 could establish functional interactions with RUNX2. Taken together, our results demonstrated that SALL1 positively regulates the commitment of odontoblast lineages by interacting with RUNX2 and directly activating Tgf-ß2 at an early stage.

11.
Theranostics ; 10(26): 12223-12240, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33204339

RESUMO

Rationale: Many viral infections are known to activate the p38 mitogen-activated protein kinase (MAPK) signaling pathway. However, the role of p38 activation in viral infection and the underlying mechanism remain unclear. The role of virus-hijacked p38 MAPK activation in viral infection was investigated in this study. Methods: The correlation of hepatitis C virus (HCV) infection and p38 activation was studied in patient tissues and primary human hepatocytes (PHHs) by immunohistochemistry and western blotting. Coimmunoprecipitation, GST pulldown and confocal microscopy were used to investigate the interaction of p38α and the HCV core protein. In vitro kinase assays and mass spectrometry were used to analyze the phosphorylation of the HCV core protein. Plaque assays, quantitative real time PCR (qRT-PCR), western blotting, siRNA and CRISPR/Cas9 were used to determine the effect of p38 activation on viral replication. Results: HCV infection was associated with p38 activation in clinical samples. HCV infection increased p38 phosphorylation by triggering the interaction of p38α and TGF-ß activated kinase 1 (MAP3K7) binding protein 1 (TAB1). TAB1-mediated p38α activation facilitated HCV replication, and pharmaceutical inhibition of p38α activation by SB203580 suppressed HCV infection at the viral assembly step. Activated p38α interacted with the N-terminal region of the HCV core protein and subsequently phosphorylated the HCV core protein, which promoted HCV core protein oligomerization, an essential step for viral assembly. As expected, SB203580 or the HCV core protein N-terminal peptide (CN-peptide) disrupted the p38α-HCV core protein interaction, efficiently impaired HCV assembly and impeded normal HCV replication in both cultured cells and primary human hepatocytes. Similarly, severe fever with thrombocytopenia syndrome virus (SFTSV), herpes simplex virus type 1 (HSV-1) or severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection also activated p38 MAPK. Most importantly, pharmacological blockage of p38 activation by SB203580 effectively inhibited SFTSV, HSV-1 and SARS-CoV-2. Conclusion: Our study shows that virus-hijacked p38 activation is a key event for viral replication and that pharmacological blockage of p38 activation is an antiviral strategy.

12.
Sensors (Basel) ; 20(22)2020 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-33207813

RESUMO

Recently, more and more smart homes have become one of important parts of home infrastructure. However, most of the smart home applications are not interconnected and remain isolated. They use the cloud center as the control platform, which increases the risk of link congestion and data security. Thus, in the future, smart homes based on edge computing without using cloud center become an important research area. In this paper, we assume that all applications in a smart home environment are composed of edge nodes and users. In order to maximize the utility of users, we assume that all users and edge nodes are placed in a market and formulate a pricing resource allocation model with utility maximization. We apply the Lagrangian method to analyze the model, so an edge node (provider in the market) allocates its resources to a user (customer in the market) based on the prices of resources and the utility related to the preference of users. To obtain the optimal resource allocation, we propose a pricing-based resource allocation algorithm by using low-pass filtering scheme and conform that the proposed algorithm can achieve an optimum within reasonable convergence times through some numerical examples.

13.
Adv Mater ; 32(45): e2003453, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33015916

RESUMO

The Plateau-Rayleigh instability (PRI) is a well-known phenomenon where a liquid column always breaks up into droplets to achieve the minimization of surface energy. It normally leads to the non-uniformity of a liquid film, which, however, is unfavorable for the fluid coating process. So far, strategies to overcome this instability rely on either the surfactants, UV/high-temp curing treatments, or specific chemical reactions, which suffer from both limited liquid composition and complicated experimental conditions. Natural mulberry silk, a typical composite fiber, is produced by silkworms through a similar fluidic coating process, but exhibits a remarkably uniform and smooth surface. Drawing inspiration, it is revealed that the unique dual parallel fibers are capable of overcoming the PRI during the fluid coating process. Such anti-PRI ability is attributable to the changes in the Laplace pressure difference caused by the alternative asymmetry of the liquid film, as has been demonstrated by both a force analysis on the irregular liquid film and theoretical simulation according to the stability of the liquid on parallel fibers in the fluid coating process. The strategy is applicable for preparing various smooth functional coatings on fibers, which offers new perspectives for fluid coating and microfluidic technologies.

14.
Small ; 16(44): e2004922, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33030805

RESUMO

For the first time Janus-like films of surface-acylated cellulose nanowhiskers (CNWs) with or without graphene oxide (GO) via one-step evaporation-driven self-assembly process are reported, which have reconstructible time-dependent micro-/nanostructures and asymmetric wettability. The heterogeneous aggregation of CNWs on rough Teflon substrates favors the formation of uniform films, leading to hydrophobic smooth bottom surface. The homogeneous nucleation of residual CNWs in bulk suspensions promotes the growth of patchy microspheres with an average diameter of 22.7 ± 2.1 µm, which precipitate on the top surface leading to enhanced hydrophobicity. These patchy microspheres are thermoresponsive and vanish after heating at 60 °C within 1 min, while they are reconstructed at room temperature with time-dependent evolving micro-/nanostructures in dry state within 2 d. The thermoresponsive transition of patchy microparticles leads to accompanied switchable change between transparency and opacity of Janus-like films. Furthermore, the incorporation of GO generates more patchy microspheres with an average diameter of 13.5 ± 1.3 µm on the top surface of hybrid Janus-like films. Different distributions of CNWs and GO in Janus-like films and the solvent-responsive self-assembled patchy microparticles of CNWs facilitate their reversible actuation by showing fast curling in THF within 6 s and flattening in water for at least 25 cycles.

15.
Int J Cardiol ; 2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33069784

RESUMO

Abnormal peripheral and coronary endothelial function has been associated with increased risk of major adverse cardiovascular events (MACE) in cross-sectional retrospective and observational studies. However, prognostic value of routine clinical evaluation, diagnosis and treatment of endothelial dysfunction on incident MACE in patients with non-obstructive coronary artery disease (NOCAD) remains unknown. Endothelial Function Guided Management in Patients with NOCAD (ENDOFIND) is a multicenter, randomized, patients-blinded, parallel-controlled, two-stage clinical trial evaluating the impact of routine clinical peripheral endothelial function testing on initiation and/or intensification of cardiovascular preventive therapies in Stage I, and on the risk of MACE in Stage II in patients with NOCAD. One thousand participants with NOCAD on clinically indicated coronary computed tomography or invasive angiography will be enrolled and randomized 1:1, after baseline peripheral endothelial function evaluation, to either endothelial function guided treatment group or standard of care control group. In Stage I, patients will be followed for 12 months and primary outcome will be the proportion of patients receiving prescriptions for cardiovascular evidence-based lipid, blood pressure and glucose lowering medications at the clinic visit immediately after endothelial function evaluation. Secondary outcomes are change in endothelial function measured as reactive hyperemia index and patients' adherence to evidence-based medications in 12 months. Study will be extended into Stage II where sample size and follow up duration will be reevaluated to ensure statistical power, and primary outcome will be incident MACE. ENDOFIND is proof-of-concept clinical trial of a disruptive endothelial function guided clinical intervention with potential benefits to NOCAD patients. CONDENSED ABSTRACT: ENDOFIND is a proof-of-concept clinical trial of a disruptive endothelial function guided clinical intervention with potential benefits to patients with no obstructive coronary artery disease (NOCAD). It is a multicenter, randomized, patients-blinded, parallel controlled two-stage clinical trial to evaluate the impact of routine clinical peripheral endothelial function testing on initiation and/or intensification of cardiovascular disease preventive therapies in Stage I, and on the risk of MACE in Stage II.

16.
Huan Jing Ke Xue ; 41(9): 3924-3931, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124271

RESUMO

The spectral characteristics and sources of water-soluble organic compounds (WSOC) in PM2.5 in winter were studied by using UV-vis absorption spectroscopy, three-dimensional fluorescence spectroscopy, parallel factor analysis, and backward trajectory model. The results showed that the concentration of WSOC in PM2.5 was 4.66-14.75 µg ·m-3. The values of E2/E3, E3/E4, S275-295, SUVA254, AAE, and MAE365 of WSOC were, respectively, in the range of 2.85-4.32, 2.21-3.56, 0.0099-0.0127 nm-1, 2.35-3.89 m2 ·g-1, 2.66-4.60, and 1.51-2.60 m2 ·g-1. The E2/E3, E3/E4, S275-295, and AAE values of WSOC at the sampling site in the southern suburb of Xi'an, China (Xi'an University of Architecture and Technology) were higher than those at the sampling site in the northern suburb (sports park), while the values of SUVA254 and MAE365 were lower. There were four fluorescent components in WSOC identified by the EEMs-PARAFAC model: C1 and C2 were fulvic acid-like and protein-like, respectively, and C3 and C4 were humus-like components. The fluorescence intensities and the sum of the fluorescent components were positively correlated with the concentrations of PM2.5, OC, WSOC, and A254 value (P<0.01). The fluorescence index (FI), biological source index (BIX), and humic index (HIX) values of WSOC were 1.75-2.12, 1.14-1.46, and 1.18-2.06, respectively. During the monitoring period, the air mass transmission trajectory was dominated by the local southwest of short-distance transmission, and its trajectory accounted for more than 50%. The pollutant emissions from Xinjiang, Inner Mongolia, and Gansu also made significant contributions to the air pollution levels in Xi'an in winter. There was a small difference in the carbon component content of PM2.5 in the northern and southern suburbs of Xi'an. The molecular weight, humification degree, and light absorption capacity of WSOC at the southern suburb sampling site were lower than those in the northern suburb where the wavelength dependence of light absorption intensity was relatively stronger. The WSOC mainly originated from biological sources or both from biological and terrestrial sources. Local transmission had the most significant contribution to PM2.5 and WSOC in winter.


Assuntos
Poluentes Atmosféricos , Material Particulado , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Material Particulado/análise , Estações do Ano , Água
17.
J Colloid Interface Sci ; 583: 470-486, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33011414

RESUMO

Temperature/pH dual-stimuli-responsive phase-change microcapsules (Dual-SR-MEPCM) were designed that can form the basis of smart drug delivery systems. They employed n-eicosane as a phase change material (PCM) microencapsulated in an acrylate-functionalized silica shell via emulsion-templated interfacial polycondensation. A poly(N-isopropylacrylamide-co-acrylate acid) functional layer was then fabricated on the surface of the silica shell through surfactant-assisted radical polymerization. The combination of phase-change microcapsules and stimuli-responsive material results in a system that synchronously implements thermal self-regulation by its PCM core together with controllable drug release through its polymeric functional layer. The resultant Dual-SR-MEPCM exhibits regularly spherical morphology, uniform particle-size distribution and well-defined core-shell microstructure, which indicates successful construction according to our design principle. This system has been further evaluated for multipurpose applications in thermal regulation and drug delivery with independent temperature and pH triggering. The Dual-SR-MEPCM not only shows a high thermal energy-storage capacity of over 160 J/g, but also good anti-leakage performance, thermal cycle stability and high-temperature shape stability. Our studies also reveal independent stimuli-responsive behaviors for temperature and pH when using bovine serum albumin and doxorubicin hydrochloride as model drugs. All of these features indicate that the Dual-SR-MEPCM designed in this study can serve as a promising candidate for smart drug delivery systems, with great potential for future multipurpose applications in advanced pharmaceutical areas.

18.
Artigo em Inglês | MEDLINE | ID: mdl-33048521

RESUMO

Quantum dot light-emitting diodes (QLEDs), particularly those capable of emitting light with tunable colors, have attracted the attention of researchers for their variability in lighting and displays. So far, various color-tunable QLEDs have been developed using techniques of inkjet printing or white light combining with color filters (CFs), which however suffered from difficulties in mass production. Here, by inserting an insulating resin layer between two conductive silver nanowire (AgNW) layers, a unique AgNWs/resin/AgNWs (A/R/A) sandwich-structured electrode was developed, showing rather small sheet resistances at both sides and high transparency. The as-prepared A/R/A electrode is applicable for making a large-area transparent red QLED with an external quantum efficiency (EQE) of 11.42% and a transmittance of 72.5%. Furthermore, the A/R/A electrode can be used as intermediate connecting electrodes to stack three single-colored QLEDs, forming a novel structured R/G/B tri-stacked QLED, which enables emission not only of primary colors red, green, and blue independently with the maximum EQE of 8.22, 8.07, and 2.28%, respectively, but also arbitrary hybrid colors that cover a 107% National Television System Committee (NTSC) color triangle. Such large-area full-color-tunable tri-stacked QLED offers new perspectives for the next-generation solid-state scene lighting and full-color displays.

19.
Rejuvenation Res ; 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33115330

RESUMO

Astaxanthin, a xanthophyll belonging to the family of carotenoids, is a potent antioxidant. The effect of astaxanthin on longevity and its physiological and molecular mechanism are still unclear. In this study, we proved that astaxanthin could prolong the lifespan of Caenorhabditis elegans. To uncover whether astaxanthin delay aging by up-regulating autophagy, we assessed the expression of autophagy genes and found that the expression of autophagy genes was up-regulated after feeding with astaxanthin compared with the control group, and the difference was statistically significant. In order to explore the molecular mechanism of astaxanthin-induced autophagy upregulation, we knocked out the key genes daf-16 or hlh-30 of Insulin/IGF-1 signal pathway and target of rapamycin signal pathway (two common conservative signal pathways capable of regulating autophagy) by RNA interference, and the expression of autophagy gene lgg-1 decreased. Collectively, our results strongly suggest that autophagy, which is both the Insulin/IGF-1 signal pathway-dependent and target of rapamycin signal pathway-dependent, plays a role in the prolongation of the lifespan of Caenorhabditis elegans by astaxanthin.

20.
J Environ Sci (China) ; 98: 85-93, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33097162

RESUMO

Surface monitoring, vertical atmospheric column observation, and simulation using chemical transportation models are three dominant approaches for perception of fine particles with diameters less than 2.5 micrometers (PM2.5) concentration. Here we explored an image-based methodology with a deep learning approach and machine learning approach to extend the ability on PM2.5 perception. Using 6976 images combined with daily weather conditions and hourly time data in Shanghai (2016), trained by hourly surface monitoring concentrations, an end-to-end model consisting of convolutional neural network and gradient boosting machine (GBM) was constructed. The mean absolute error, the root-mean-square error and the R-squared for PM2.5 concentration estimation using our proposed method is 3.56, 10.02, and 0.85 respectively. The transferability analysis showed that networks trained in Shanghai, fine-tuned with only 10% of images in other locations, achieved performances similar to ones from trained on data from target locations themselves. The sensitivity of different regions in the image to PM2.5 concentration was also quantified through the analysis of feature importance in GBM. All the required inputs in this study are commonly available, which greatly improved the accessibility of PM2.5 concentration for placed and period with no surface observation. And this study makes an exploratory attempt on pollution monitoring using graph theory and deep learning approach.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , China , Material Particulado , Tempo (Meteorologia)
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