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1.
Adv Sci (Weinh) ; 11(15): e2308200, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342623

RESUMO

Realizing efficient energy utilization from the heat source of the sun and the cold source of outer space is of great significance for addressing the global energy and environmental crisis. Materials with ideal full-spectrum solar absorption and infrared emission are highly desirable for adapting to the continuous weather dynamic throughout the day, nonetheless, their development remains challenging. Here, a polymer nanocomposite with full-spectrum strong solar (280-2500 nm) absorption ranging from 88.8% to 94.8% with an average value of 93.2% and full-spectrum high infrared (8-13 µm) emission ranging from 81.3% to 90.0% with an average value of 84.2%, is reported by melt-processing polypropylene and uniformly dispersed low-loading MXene nanosheets (1.9 vol%). The nanocomposite can achieve daytime photothermal enhancement of ≈50 °C and nighttime radiative cooling of 8 °C. The temperature difference throughout the day ensures all-day uninterrupted thermoelectric generation, yielding a power density output of 1.5 W m-2 (daytime) and 7.9 mW m-2 (nighttime) in real outdoor environment without any additional energy consumption. This work provides an impressive polymer nanocomposite with ideal full-spectrum solar absorption and infrared emission for all-day uninterrupted thermal energy management and conversion.

2.
J Hazard Mater ; 468: 133785, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367441

RESUMO

BACKGROUND: Although growing evidence has shown independent links of long-term exposure to fine particulate matter (PM2.5) with cognitive impairment, the effects of its constituents remain unclear. This study aims to explore the associations of long-term exposure to ambient PM2.5 constituents' mixture with cognitive impairment in Chinese older adults, and to further identify the main contributor. METHODS: 15,274 adults ≥ 65 years old were recruited by the Chinese Longitudinal Healthy Longevity Study (CLHLS) and followed up through 7 waves during 2000-2018. Concentrations of ambient PM2.5 and its constituents (i.e., black carbon [BC], organic matter [OM], ammonium [NH4+], sulfate [SO42-], and nitrate [NO3-]) were estimated by satellite retrievals and machine learning models. Quantile-based g-computation model was employed to assess the joint effects of a mixture of 5 PM2.5 constituents and their relative contributions to cognitive impairment. Analyses stratified by age group, sex, residence (urban vs. rural), and region (north vs. south) were performed to identify vulnerable populations. RESULTS: During the average 3.03 follow-up visits (89,296.9 person-years), 4294 (28.1%) participants had developed cognitive impairment. The adjusted hazard ratio [HR] (95% confidence interval [CI]) for cognitive impairment for every quartile increase in mixture exposure to 5 PM2.5 constituents was 1.08 (1.05-1.11). BC held the largest index weight (0.69) in the positive direction in the qg-computation model, followed by OM (0.31). Subgroup analyses suggested stronger associations in younger old adults and rural residents. CONCLUSION: Long-term exposure to ambient PM2.5, particularly its constituents BC and OM, is associated with an elevated risk of cognitive impairment onset among Chinese older adults.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Disfunção Cognitiva , Humanos , Idoso , Material Particulado/toxicidade , Estudos de Coortes , Poluentes Atmosféricos/toxicidade , Exposição Ambiental , Disfunção Cognitiva/induzido quimicamente , Disfunção Cognitiva/epidemiologia , China/epidemiologia , Poluição do Ar/efeitos adversos
3.
Mol Cell Biochem ; 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38180718

RESUMO

Methyltransferase like 3 (METTL3) has been reported to promote tumorigenesis of multiple myeloma (MM), however, the molecular mechanism still needs further research. The N6-methyladenosine (m6A) level in tissues or cells was measured by m6A kit and dot blot assay. The mRNA and protein expression were detected by quantitative real-time PCR (RT-qPCR) and Western blot, respectively. The cell counting kit-8 and colony formation assay were used to detect the cell proliferation. Coimmunoprecipitation (Co-IP) experiment verified the binding of two proteins. The luciferase reporter experiment demonstrated the targeted binding of miR-182-5p and CaMKII inhibitor 1 (CAMK2N1). More importantly, tumor growth was measured in xenograft mice. Our data showed that the expression of METTL3 was significantly increased in MM patients' samples and MM cells. METTL3 overexpression promoted MM cells proliferation, and METTL3 knockdown inhibited MM cells proliferation. Mechanically, METTL3-dependent m6A participated in DiGeorge syndrome critical region 8 (DGCR8)-mediated maturation of pri-miR-182. Upregulation of miR-182-5p further enhanced the promoting proliferation effect of METTL3 overexpression on MM cells. Moreover, the luciferase reporter gene experiment proved that miR-182-5p targetedly regulated CAMK2N1 expression. Xenograft tumor in nude mice further verified that METTL3 promoted MM tumor growth through miR-182/CAMK2N1 signal axis. In summary, the METTL3/miR-182-5p/CAMK2N1 axis plays an important role in MM tumorigenesis, which may provide a new target for MM therapy.

4.
Polymers (Basel) ; 15(22)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-38006187

RESUMO

Biodegradable plastics are attracting attention as a solution to the problems caused by plastic waste. Among biodegradable plastics, polylactide (PLA) and poly (butylene succinate) (PBS) are particularly noteworthy because of their excellent biodegradability. However, the drawbacks of their mechanical properties prompts the need to compound them to achieve the desired strength. The characteristics of the interface of the composite material determine the realization of its final performance. The study of the interface and microstructure of composites is essential for the development of products from degradable polymers. The morphology evolution and microcrystal structure of spin-casted fully biodegradable (PLA/PBS) blend films were investigated using atomic force microscopy (AFM)-based nanomechanical mapping. Results show that intact blend films present an obvious phase separation, where the PBS phase is uniformly dispersed in the PLA phase in the form of pores. Furthermore, the size and number of the PBS phase have a power exponential relationship and linear relationship with PBS loading, respectively. Intriguingly, after annealing at 80 °C for 30 min, the PLA phase formed an orderly petal-like microcrystalline structure centered on the PBS phase. Moreover, the microcrystalline morphology changed from a "daisy type" to a "sunflower type" with the increased size of the PBS phase. Since the size of the PBS phase is controllable, a new method for preparing microscopic patterns using fully biodegradable polymers is proposed.

5.
ACS Nano ; 17(3): 2029-2038, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36638216

RESUMO

Passive radiative cooling (PRC) and passive radiative heating (PRH) have drawn increasing attention as green and sustainable cooling and heating approaches, respectively. Existing material designs for PRC/PRH are usually static and unsuitable for dynamic seasonal and weather changes. Herein, we demonstrate an all-day dual-mode film fabricated by decorating MXene nanosheets on porous poly(vinylidene fluoride) with abundant coral-like hierarchical structures obtained via phase inversion. The cooling side of the dual-mode film exhibits high solar reflectivity (96.7%) and high infrared emissivity (96.1%). Consequently, daytime subambient radiative cooling of 9.8 °C is achieved with a theoretical cooling power of 107.5 W/m2 and nighttime subambient cooling of 11.7 °C is achieved with a theoretical cooling power of 140.7 W/m2. Meanwhile, the heating side of the dual-mode film exhibits low infrared emissivity (11.6%) and high solar absorptivity (75.7%), contributing to a PRH capability of 8.1 °C, and excellent active solar and Joule heating as effective compensation for PRH. The dual-mode film could be easily switched between cooling and heating modes by flipping it to adapt to dynamic cooling and heating scenarios, which is important for alleviating the energy crisis and reducing greenhouse emissions.

6.
Adv Sci (Weinh) ; 10(10): e2206044, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36670052

RESUMO

Smart windows with light management and indoor solar heating modulation capacities are of paramount importance for building energy conservation. Thermochromic poly(N-isopropylacrylamide) (PNIPAm) hydrogel smart windows exhibit advantages of the relatively suitable transition temperature of 32 °C, high cost-effective and automatic passive sunlight regulation, but sustain slow response rate and unsatisfactory solar modulation efficiency. Herein, a strategy of one-step copolymerization of NIPAm and different olefine acids (OA) using reverse atom transfer radical polymerization method is developed to fabricate various chain/microparticle hybrids (CMH) for liquid energy-saving windows. Synergetic mechanisms of thermal-induced dissolution and aggregation of linear polymer chains integrated with water capture and release of microgel particles contribute to tunable light-scattering behaviors and adaptive solar modulation. Without any post-treatment, the as-prepared poly(N-isopropylacrylamide-co-acrylic acid) (P(NIPAm-co-AA))-based CMH suspension is injected into sandwich glass to construct energy-saving windows, which exhibits appreciated near-room-temperature transition (26.7 °C), rapid response (5 s), extraordinary luminous transmittance (91.5%), and solar modulation efficiency (85.8%), resulting in a substantial decline of indoor temperature of 24.5 °C in simulation experiment. Combining the versatile strategy with flexible adjustment on transition temperature, multifarious P(NIPAm-co-OA)-based CMH windows with eminent light management capacity are obtained. This work will powerfully promote the development and renovation of energy-efficient windows.

7.
Mater Horiz ; 10(1): 235-247, 2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36367197

RESUMO

High-strength nonmetallic materials with low infrared (IR) emission are rare in nature, yet highly anticipated especially in military and aerospace fields for thermal camouflage, IR stealth, energy-saving heating. Here, we reported a high-strength (422 MPa) nonmetallic film with very low IR emissivity (12%), realized by constructing alternating multilayered structures consisting of successive MXene functionalized outer layers and continuous GO reinforced inner layers. This nonmetallic film is capable of competing with typical stainless steel (415 MPa, 15.5%), and exhibits remarkable thermal camouflage performance (ΔT = 335 °C), ultrahigh Joule heating capability (350 °C at 2 V), excellent solar-to-thermal conversion efficiency (70.2%), and ultrahigh specific electromagnetic interference shielding effectiveness (83 429 dB cm-1). Impressively, these functionalities can be maintained well after prolonged outdoor aging, and even after undergoing harsh application conditions including strong acid/alkali and boiling water immersion, and cryogenic (-196 °C) temperature.

8.
Curr Opin Hematol ; 30(1): 4-13, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36165537

RESUMO

PURPOSE OF REVIEW: Hematological malignancies are a kind of systemic cancers mostly related to abnormal differentiation of blood stem cells. Because of the poor prognosis, chemotherapy resistance and common recurrence, new mechanisms and treatment therapies are looking forward to be discovered. RECENT FINDINGS: Over the years, epigenetic abnormalities have been known to act a key part in occurrence and development of hematological tumors. In the internal modifications on long noncoding eukaryotic mRNA, there is a common type called N6-methyladenosine that can change the expression of target genes and participate in the translation, degradation and splicing of mRNA. M6A is related to a wealth of cancers, such as HNRNPA2B1's elevation in multiple myeloma, METTLE3's elevation in acute myeloid leukemia and lung cancer. Immune cells, playing a significant role in hematological cancers, can also be regulated by m6A. SUMMARY: In the review, we summarized the recent progress on hematological malignancies associating with m6A and immune cells, which may offer a new road for the treatment of them.


Assuntos
Neoplasias Hematológicas , Neoplasias , Humanos , Neoplasias/metabolismo , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/terapia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Diferenciação Celular
9.
Int J Mol Sci ; 23(21)2022 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-36362009

RESUMO

This study aims to investigate the effects of CLAUDIN-6 (CLDN6) on cell apoptosis and proliferation of bovine cumulus cells (CCs). Immunofluorescence staining was used to localize CLDN6 protein in CCs. Three pairs of siRNA targeting CLDN6 and one pair of siRNA universal negative sequence as control were transfected into bovine CCs. Then, the effective siRNA was screened by real-time quantitative PCR (RT-qPCR) and Western blotting. The mRNA expression levels of apoptosis related genes (CASPASE-3, BAX and BCL-2) and proliferation related genes (PCNA, CDC42 and CCND2) were evaluated by RT-qPCR in CCs with CLDN6 knockdown. Cell proliferation, apoptosis and cell cycle were detected by flow cytometry with CCK-8 staining, Annexin V-FITC staining and propidium iodide staining, respectively. Results showed that the CLDN6 gene was expressed in bovine CCs and the protein was localized in cell membranes and cytoplasms. After CLDN6 was knocked down in CCs, the cell apoptosis rate significantly decreased and the pro-apoptotic genes BAX and CASPASE-3 were down-regulated significantly, whereas the anti-apoptotic gene BCL-2 was markedly up-regulated (p < 0.05). Additionally, CLDN6 knockdown significantly enhanced cell proliferation of CCs at 72 h after siRNA transfection. The mRNA levels of proliferation-related genes PCNA, CCND2 and CDC42 increased obviously in CCs with CLDN6 knockdown (p < 0.05). After CLDN6 was down-regulated, the percentage of CCs at S phase was significantly increased (p < 0.05). However, there was no remarkable difference in the percentages of cells at the G0/G1 phase and G2/M phase between CCs with or without CLDN6 knockdown (p > 0.05). Therefore, the expression of CLDN6 and its effects on cell proliferation, apoptosis and cell cycle of bovine CCs were first studied. CLDN6 low expression inhibited cell apoptosis, induced cell proliferation and cell cycle arrest of bovine CCs.


Assuntos
Apoptose , Células do Cúmulo , Feminino , Bovinos , Animais , Caspase 3/genética , Caspase 3/metabolismo , Proteína X Associada a bcl-2/metabolismo , RNA Interferente Pequeno/metabolismo , Células do Cúmulo/metabolismo , Antígeno Nuclear de Célula em Proliferação , Linhagem Celular Tumoral , Apoptose/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proliferação de Células/genética , RNA Mensageiro/metabolismo
10.
ACS Nano ; 16(11): 18959-18967, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36342787

RESUMO

The demand for thermally conductive but electrically insulating materials has increased greatly in advanced electronic packaging. To this end, polymer-based composites filled with boron nitride (BN) nanosheets have been intensively studied as thermal interface material (TIM). However, it remains a great challenge to achieve isotropically ultrahigh thermal conductivity in BN/polymer composites due to the inherent thermal property anisotropy of BN nanosheets and/or the insufficient construction of the 3D thermal conductive network. Herein, we present a high-performance BN/polymer composite with a biaxially oriented thermal conductive network by a dendritic ice template. The composite exhibits both ultrahigh in-plane (∼39.0 W m-1 K-1) and through-plane thermal conductivity (∼11.5 W m-1 K-1) at 80 vol % BN loading, largely exceeding those of reported BN/polymer composites. In addition, our composite as a TIM shows higher cooling efficiency than that of commercial TIM with up to 15 °C reduction of the chip temperature and retains good thermal stability even after 1000 heating/cooling cycles. Our strategy represents an effective approach for developing advanced thermal interface materials, which are greatly demanded for advanced electronics and emerging areas like wearable electronics.

11.
Theriogenology ; 188: 28-36, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35661480

RESUMO

The expression and function of bone morphogenetic protein 4 (BMP4) gene in bovine cumulus cells (CCs) was investigated to reveal the mechanisms by which it regulated cell apoptosis and proliferation. The mRNA and protein expression of BMP4 were detected using quantitative PCR (qPCR) and immunofluorescence staining in CCs. The effective siRNAs against BMP4 gene were screened using qPCR and western blotting. The mRNA expression levels of apoptosis-related genes and proliferation-related genes were estimated by qPCR after knocking-down the BMP4 gene in bovine CCs. Cell apoptosis, proliferation and cell cycle were measured with Annexin V-FITC, CCK-8 and propidium iodide staining by flow cytometry. Results showed that the BMP4 gene was expressed and its protein was in the cytoplasm and nuclei of bovine CCs. The BMP4 knockdown increased the cell apoptosis rate and upregulated the mRNA levels of apoptosis genes CASPASE-3 and BAX with downregulation of the anti-apoptosis gene BCL-2 (P < 0.05). The proliferation rate declined and the mRNA expression levels of proliferation-related genes PCNA, CDC42 and CCND2 were downregulated in the bovine CCs with BMP4 low expression (P < 0.05). The BMP4 knockdown significantly increased the percentage of G0/G1 phase cells while decreased that of S phase cells. Therefore, the expression of BMP4 and its biological functions on the cell proliferation, apoptosis and cell cycle of bovine CCs were first studied. BMP4 knockdown induced cell apoptosis, cell cycle arrest and inhibited proliferation of bovine CCs.


Assuntos
Apoptose , Células do Cúmulo , Animais , Proteína Morfogenética Óssea 4/genética , Proteína Morfogenética Óssea 4/farmacologia , Bovinos , Proliferação de Células , Células do Cúmulo/metabolismo , Feminino , RNA Mensageiro/metabolismo
12.
Diabetes Metab Syndr Obes ; 15: 1165-1171, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464260

RESUMO

Purpose: To establish a high-glucose (HG) stressed cell model and study the expression of main components of the Dll4/Notch-VEGF signaling pathway under high-glucose stimulation. Methods: A model of HG-conditioned cells (human umbilical vein endothelial cells, HUVECs) was first established, and then the expression of Dll4, Notch1, Notch4 and VEGF in HG-stressed cells with or without Notch pathway blockage was analyzed by RT-PCR and Western blot. To observe cell migration, we also evaluated the Transwell assay. Results: HUVECs stimulated with 30mmol/L HG was selected as a cell model. RT-PCR and Western blot results showed that HG stimulation induced the expression of Dll4, Notch1 and VEGF and downregulated Notch4. The expressions were reversed after Notch pathway blockage; meanwhile, the blockage of Notch pathway inhibited cell migration under HG condition. Conclusion: The function of Notch4 in responses to HG stimulation deserves further researching. Combination therapy by blocking Dll4/Notch and VEGF pathways may provide us with a new way for anti-neovascularization.

13.
Drug Dev Res ; 83(4): 1016-1023, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35253245

RESUMO

Oxidative stress alters cellular microenvironment, facilitating cell apoptosis and inflammatory response, and oxidation of lens constituents may ultimately result in cataracts. Astragaloside IV (AS-IV) exhibits a variety of pharmacological activities, such as antioxidative and anti-inflammatory activity via regulating various signaling pathways. However, the effect of AS-IV on lens epithelial cells and its potential therapeutic role in cataracts remained to be investigated. In this study, AS-IV prevented H2 O2 -induced injury and inflammatory response in human lens epithelial cell line HLE-B3 through inhibiting NLRP3 inflammasome in a mitogen-activated protein kinase-dependent pathway, providing a potential novel therapeutic strategy for cataracts.


Assuntos
Catarata , Inflamassomos , Catarata/tratamento farmacológico , Catarata/metabolismo , Células Epiteliais , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Estresse Oxidativo , Saponinas , Triterpenos
14.
Carbohydr Polym ; 276: 118753, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34823782

RESUMO

Unstable hydrogel-substrate interfaces and defunctionalization at low temperature severely restrict versatile applications of hydrogel-based systems. Herein, various chitosan-polyacrylamide double-network (CS-PAM DN) ionic hydrogels were chemically linked with diverse substrates to construct robust and anti-freezing hydrogel-substrate combination, wherein the destructible CS physical network rendered effective energy dissipation mechanism to significantly enhanced the cohesion of hydrogels and the covalent linkage between PAM network with substrate surface strongly improved the interfacial adhesion. The synergistic effects enabled the CS-PAM DN hydrogels to be tightly bonded on diverse metals and inorganics. Impressively, the hydrogel-substrate combinations were freezing tolerant to well-maintain high interfacial toughness at low temperature. Notably, due to the high toughness and conductivity of hydrogel-metal interface, the hydrogel-metal combination can be utilized as a multi-model flexible sensor to detect strain and pressure within broad temperature range. This work may provide a platform for construction and emerging application of robust, anti-freezing and stable-performance hydrogel-based systems.

15.
BMJ Open ; 11(12): e045275, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893481

RESUMO

OBJECTIVE: This study aimed to systematically review the relationship between dry eye disease (DED) and asthma based on published population-based studies. DATA SOURCES: PubMed, EMBASE and ISI Web of Science from their inception were searched up to October 2019. STUDY SELECTION: Observational studies addressing the association between asthma and DED will be eligible. DATA EXTRACTION AND SYNTHESIS: Two reviewers independently conducted the data extraction and quality assessment. We used a random-effects model for all analyses. Subgroup analysis according to ethnicity was performed to test the influence of ethnicity on the association. MAIN OUTCOMES AND MEASURES: Six independent studies (a total of 45 215 patients with asthma and 232 864 control subjects) were included in this review and had an average of seven stars by the Newcastle-Ottawa Scale. Our current findings suggest that the prevalence of DED was higher in the asthma group than in the control group (Z=7.42, p<0.00001; OR 1.29, 95% CI 1.20 to 1.38). In the subgroup analysis by ethnicity, Australian, Caucasian and Asian patients with asthma showed an increased risk of DED.


Assuntos
Asma , Síndromes do Olho Seco , Asma/epidemiologia , Austrália , Síndromes do Olho Seco/epidemiologia , Humanos , Prevalência
16.
ACS Nano ; 15(7): 11396-11405, 2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34165297

RESUMO

Heating the human body to maintain a relatively constant temperature is pivotal for various human functions. However, most of the current heating strategies are energy-consuming and energy-wasting and cannot cope with the complex and changing environment. Developing materials and systems that can heat the human body precisely via an efficient energy-saving approach no matter indoors/outdoors, day/night, and sunny/cloudy is highly anticipated for mitigating the growing energy crisis and global warming but is still a great challenge. Here, we demonstrate the low mid-infrared radiative (mid-IR) emissivity characteristic of Ti3C2Tx MXene and then apply it for energy-free passive radiative heating (PRH) on the human body. Our strategy is realized by simply decorating the cheap nanoporous polyethylene (nanoPE) textile with MXene. Impressively, the as-obtained 12 µm thick MXene/nanoPE textile shows a low mid-IR emissivity of 0.176 at 7-14 µm and outstanding indoor PRH performance on the human body, which enhances by 4.9 °C compared with that of traditional 576 µm thick cotton textile. Meanwhile, the MXene/nanoPE textile exhibits excellent active outdoor solar heating and indoor/outdoor Joule heating capability. The three heating modes integrated in this wearable MXene/nanoPE heating system can be switched easily or combined arbitrarily, making this thin heating system able to heat the human body precisely in various scenarios like indoors/outdoors, day/night, and sunny/cloudy, providing multiple promising and energy-saving solutions for future all-day personal precision thermal management.


Assuntos
Nanoporos , Polietileno , Humanos , Calefação , Titânio , Têxteis
17.
Sci Total Environ ; 783: 146948, 2021 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-33865118

RESUMO

Developing models that can accurately simulate groundwater level is important for water resource management and aquifer protection. In particular, machine learning tools provide a new and promising approach to efficiently forecast long-term groundwater table fluctuations without the computational burden of building a detailed flow model. This study proposes a multistep modeling framework for simulating groundwater levels by combining the wavelet transform (WT) with the long short-term memory (LSTM) network; the framework is named the combined WT-multivariate LSTM (WT-MLSTM) method. First, the WT decomposes the groundwater level time series (i.e., the training stage) into a self-control term and a set of external-control terms. Second, Pearson correlation analysis reveals the correlations between the influencing factors (i.e., river stage) and the groundwater table, and the multivariate LSTM model incorporating external factors is built to simulate the external-control terms. Third, the spatiotemporal evolution of the groundwater level is modeled by reconstructing the sequence of each term of the groundwater level time series. Methodological applications in the Liangshui River Basin, Beijing, China and the Cibola National Wildlife Refuge along the lower Colorado River, United States, show that the combined WT-MLSTM model has a higher simulation accuracy than the standard LSTM, MLSTM, and WT-LSTM models. A comparison between the combined WT-MLSTM model and support vector machine (SVM) also demonstrates the advantage of the proposed model. Additional comparison between model forecasts and observed groundwater levels shows the model predictability for short-term time series. Further analysis reveals that the applicability of the combined WT-MLSTM model decreases with increasing distance between the groundwater well and adjacent river channel, or with the increasing complexity of the changing groundwater level patterns, which may be driven by additional controlling factors. This study therefore provides a new methodology/approach for the rapid and accurate simulation and prediction of groundwater level.

18.
J Mater Chem B ; 8(48): 11010-11020, 2020 12 23.
Artigo em Inglês | MEDLINE | ID: mdl-33188676

RESUMO

Conductive hydrogels are capturing intensive attention for versatile applications in flexible wearable devices on account of their unique combination of softness, stretchability, conductivity and biocompatibility. However, most of the hydrogel sensors can only serve as single-type sensors to detect strain or pressure, accompanied by a limited detection range. Moreover, the poor anti-freezing performance is also a serious problem to be addressed for their practical applications. Herein, a multi-model, large range and anti-freezing hydrogel sensor was constructed from a high-mechanical and ionic conductive multi-crosslinked poly(vinyl alcohol) (M-PVA) hydrogel, which was prepared via incorporating chain entanglement interaction and complexation between Fe3+ ions and hydroxyl groups into the microcrystalline network through immersion treatment in Fe2(SO4)3 solution. The three reversible and reconstructable crosslinks within the M-PVA hydrogel worked in tandem to achieve ultra-stretchability (1120%), supercompressibility (98%), high toughness, fast self-recoverability and excellent fatigue resistance. Meanwhile, the introduction of Fe3+ and SO42- ions endowed the M-PVA hydrogel with good ionic conductivity and remarkable anti-freezing properties (-50 °C), which benefited the M-PVA hydrogel to act as a freezing-tolerant dressing. The assembled multi-model hydrogel sensor can sensitively and stably detect large range elongation (∼900%), compression (∼70%), bend and pressure (up to 4.60 MPa) concurrently, as well as various human activities including speaking, finger bending and treading behavior. Notably, the hydrogel sensor was capable of maintaining excellent mechanical flexibility and sensitive sensing capacity at low temperature. The M-PVA hydrogel is a promising flexible sensing material for versatile applications in ionic skin, motion recognition and intelligent wearable devices.


Assuntos
Congelamento/efeitos adversos , Movimento (Física) , Álcool de Polivinil/síntese química , Dispositivos Eletrônicos Vestíveis , Animais , Humanos , Masculino , Ratos , Ratos Sprague-Dawley , Estresse Mecânico
19.
Polymers (Basel) ; 12(11)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238571

RESUMO

In this paper we designed greener rubber nanocomposites exhibiting high crosslinking density, and excellent mechanical and thermal properties, with a potential application in technical fields including high-strength and heat-resistance products. Herein 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc) ionic liquid was combined with silane coupling agent to formulate the nanocomposites. The impact of [EMIM]OAc on silica dispersion in a nitrile rubber (NBR) matrix was investigated by a transmission electron microscope and scanning electron microscopy. The combined use of the ionic liquid and silane in an NBR/silica system facilitates the homogeneous dispersion of the silica volume fraction (φ) from 0.041 to 0.177 and enhances crosslinking density of the matrix up to three-fold in comparison with neat NBR, and also it is beneficial for solving the risks of alcohol emission and ignition during the rubber manufacturing. The introduction of ionic liquid greatly improves the mechanical strength (9.7 MPa) with respect to neat NBR vulcanizate, especially at high temperatures e.g., 100 °C. Furthermore, it impacts on rheological behaviors of the nanocomposites and tends to reduce energy dissipation for the vulcanizates under large amplitude dynamic shear deformation.

20.
Medicine (Baltimore) ; 99(41): e22519, 2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33031292

RESUMO

BACKGOUN: Asthma and dry eye disease are common clinical diseases. Studies have shown that asthma is related to dry eye, but there is no high-quality evidence-based medical evidence. METHOD: This protocol and final study will be conducted in accordance with the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols 2015 statement. We will search PubMed, EMBASE, ISI Web of Science, China National Knowledge Infrastructure for all relevant literature published from their inception up to August 1, 2020. Literature search, data extraction, and quality assessment will be carried out independently by two researchers, and a third researcher will resolve differences when necessary. The association between dry eye disease and asthma will indicate as odds ratio with 95% confidence interval and statistically analyzed using RevMan 5.3 software. If the studies included have high heterogeneity, we will conduct sensitivity analysis and subgroup analysis. RESULTS: The protocol is intended to guide a meta-analysis aimed at identifying and quantifying the association between asthma and dry eye disease.


Assuntos
Asma/epidemiologia , Síndromes do Olho Seco/epidemiologia , Humanos , Metanálise como Assunto , Razão de Chances , Projetos de Pesquisa , Fatores de Risco , Revisões Sistemáticas como Assunto
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