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1.
Clin Chim Acta ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32067994

RESUMO

Xanthinuria is a rare genetic metabolic disorder, the biochemical mechanism of xanthinuria is the disturbance of purine to uric acid metabolism due to the deficiency of xanthine dehydrogenase/xanthine oxidase (XDH/XO) and aldehyde oxidase 1 (AOX1). Xanthinuria has large clinical variability and only about half of all patients have urolithiasis. In this article, we present one xanthinuria case from an unrelated family, which diagnosed by clinical, biochemical and finally confirmed by molecular genetics. One mutation in XDH gene c.2737C>T (p.R913W) and another mutation in SEPT9 gene (c.655C>T (p.R219W)) were identified. To our knowledge, this is the first time that these novel mutations reported in the xanthinuria patients.

2.
Sci Total Environ ; 714: 136880, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-32018994

RESUMO

Here, a novel chemiluminescence (CL) immunoassay was fabricated for sensitive determination of tetrabromobisphenol A bis(2-hydroxyethyl) ether (TBBPA-DHEE), one of typical tetrabromobisphenol A derivatives. At the indirectly competitive method, the synthesized PS@hemin@Co2+ was labelled by secondary antibody (Ab2) instead of common natural enzymes, which showed excellent catalysis towards the decomposition of luminol-H2O2 for producing CL signal. Furthermore, the CL signal was greatly amplified owing to the synergistic catalysis of hemin and Co2+ in the detection system. Under the optimized conditions, the established method offered (i) low detection limit (LOD, 0.9 µg/L), which was almost 5 times lower than that using a conventional ELISA with the same antibody; (ii) a good linearity (1.6-14.3 µg/L); (iii) satisfactory accuracy and precision (recoveries, 89.67-125.33%; CV, 2.75-8.37%). The proposed CL immunoassay was applied for analysis of environmental samples from various sources collected from Jiangsu and Zhejiang province, China. And the detected concentrations were ranged in 2.4-3.7 µg/L in environmental waters and 1.8-2.4 ng/g (dry weight, dw) in soil samples, indicating great potential for trace TBBPA-DHEE detection from environmental samples.

3.
Rev Sci Instrum ; 91(1): 014703, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32012643

RESUMO

A pulsed intense magnetic field device was developed for the Shanghai Shenguang-II (SG-II) laser facility. The device using a double-turn coil with 12 mm diameter is capable of producing a peak current of 42 kA with 280 ns rising edge and 200 ns flat top width. A peak magnetic field of 8.8 T is achieved at the center of the coil. A two-section transmission line composed by a flexible section and a rigid section is designed to meet the target chamber environment of SG-II laser facility. The flexible section realizes the soft-connection between the capacitor bank and the target chamber, which facilitates the installation of the magnetic field device and the adjustment of the coil. The rigid section is as small as possible so that it can be inserted into the target chamber from any smallest flange, realizing elastic magnetic field configuration. The magnetic coil inside the chamber can be adjusted finely through a mechanical component on the rigid transmission line outside the target chamber. The adjustment range is up to 5 cm in both radial and axial directions with ∼50 µm precision. The device has been successfully operated on SG-II laser facility.

4.
Plant Physiol ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32019874

RESUMO

Triacylglycerols (TAGs) are the major storage form of seed oil in oilseed plants. They are biosynthesized de novo in seed plastids and then transported into the endoplasmic reticulum. However, the transport mechanism for plastid fatty acids in developing seeds remains unknown. Here, we isolated two novel plastid fatty acid exporters (FATTYACID EXPORT 2 and 4; FAX2 and FAX4) specifically abundant in seed embryos during the seed-filling stage in Arabidopsis (Arabidopsis thaliana). FAX2 and FAX4 were both localized to the chloroplast membrane. FAX2 and FAX4 loss-of-function mutations caused deficiencies in embryo and cotyledon development. Seeds of fax2fax4double mutants exhibited significantly reduced TAG contents but elevated levels of plastid lipid contents compared with those of wild-type plants. By contrast, overexpression of FAX2 or FAX4 enhanced TAG deposition. Seed-feeding experiments showed that the two FAX proteins transported14C-plastid fatty acids and 13C-oleic acids for TAG biosynthesis during the seed-filling stage. Together, our data demonstrate that FAX2 and FAX4 play critical roles in transporting plastid fatty acids for TAG biosynthesis during seedembryo development. These two transporters may have broad application for increasing oil yield in oilseed crops.

5.
Int J Colorectal Dis ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32020267

RESUMO

INTRODUCTION: Perineal hernia is a protrusion of the pelvic floor which contains intra-abdominal viscera. The occurrence of perineal hernia after abdominoperineal resection (APR) is rare, but it has been reported in recent years that the incidence of perineal hernia after rectal cancer surgery has increased. This has been attributed to a shift towards extralevator abdominoperineal resection, together with more frequent and long-term use of neoadjuvant therapy. PRESENTATION OF CASE: Here, we report a patient with perineal hernia 5 years after APR surgery for rectal cancer. We decided to perform robot-assisted laparoscopic surgery on this patient using the da Vinci Surgical System. The perineal hernia was repaired by primary closure with the placement of a non-absorbable synthetic mesh as reinforcement for the pelvic floor. No complications occurred during the operation, and the patient was discharged on the third day after the operation. Clinical follow-up proceeded at the designated time intervals without difficulties. DISCUSSION: The recurrence rates of perineal hernia are still very high, and due to poor view, suturing, and mesh placement in the deep pelvis, surgeons face many challenges. Many methods have been described, but there is still no consensus as to the optimal repair technique for perineal hernia. CONCLUSION: Perineal hernias can be repaired with robot-assisted laparoscopy. Furthermore, compared with the open and laparoscopic methods, suturing and mesh placement are easier with the robot approach.

6.
Sensors (Basel) ; 20(3)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32024030

RESUMO

Due to the narrow row spacing of corn, the lack of light in the field caused by the blocking of branches, leaves and weeds in the middle and late stages of corn growth, it is generally difficult for machinery to move between rows and also impossible to observe the corn growth in real time. To solve the problem, a robot for corn interlines information collection thus is designed. First, the mathematical model of the robot is established using the designed control system. Second, an improved convolutional neural network model is proposed for training and learning, and the driving path is fitted by detecting and identifying corn rhizomes. Next, a multi-body dynamics simulation software, RecurDyn/track, is used to establish a dynamic model of the robot movement in soft soil conditions, and a control system is developed in MATLAB/SIMULINK for joint simulation experiments. Simulation results show that the method for controlling a sliding-mode variable structure can achieve better control results. Finally, experiments on the ground and in a simulated field environment show that the robot for field information collection based on the method developed runs stably and shows little deviation. The robot can be well applied for field plant protection, the control of corn diseases and insect pests, and the realization of human-machine separation.

7.
FEBS Lett ; 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32049361

RESUMO

Adenosine deaminase acting on RNA 1 (ADAR1) has been shown to participate in the regulation of endothelial cells (ECs), as well as local and systemic inflammatory responses. Here, we find that bacterial lipopolysaccharide (LPS)-induced upregulation of ADAR1 in lung ECs is impaired in aged mice, an animal model with high rates of sepsis and mortality. Endothelial cell-specific ADAR1 knockout (ADAR1ECKO ) mice suffer from higher mortality rates, aggravated lung injury, and increased vascular permeability under LPS challenge. In primary ADAR1 knockout ECs, expression of the melanoma differentiation-associated gene 5 (MDA5), a downstream effector of ADAR1, is significantly elevated. MDA5 knockout completely rescues the postnatal offspring death of ADAR1ECKO mice. However, there is no reduction in mortality or apoptosis in lung cells of ADAR1ECKO /MDA5-/- mice challenged with LPS, indicating the involvement of an MDA5-independent mechanism in this process.

8.
Nat Commun ; 11(1): 875, 2020 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-32054863

RESUMO

The emerging heterogeneous membranes show unprecedented superiority in harvesting the osmotic energy between ionic solutions of different salinity. However, the power densities are limited by the low interfacial transport efficiency caused by a mismatch of pore alignment and insufficient coupling between channels of different dimensions. Here we demonstrate the use of three-dimensional (3D) gel interface to achieve high-performance osmotic energy conversion through hybridizing polyelectrolyte hydrogel and aramid nanofiber membrane. The ionic diode effect of the heterogeneous membrane facilitates one-way ion diffusion, and the gel layer provides a charged 3D transport network, greatly enhancing the interfacial transport efficiency. When used for harvesting the osmotic energy from the mixing of sea and river water, the heterogeneous membrane outperforms the state-of-the-art membranes, to the best of our knowledge, with power densities of 5.06 W m-2. The diversity of the polyelectrolyte and gel makes our strategy a potentially universal approach for osmotic energy conversion.

9.
J Chem Phys ; 152(4): 044702, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32007048

RESUMO

Surface chemistry and photochemistry of small molecules on the rutile TiO2(001) and TiO2(011)-(2 × 1) surfaces were studied by low energy electron diffraction, thermal desorption spectroscopy, and x-ray photoelectron spectroscopy. It was found that the TiO2(001) surface mainly exhibits the defects of Ti interstitials in the near-surface region, while the TiO2(011)-(2 × 1) surface mainly exhibits the defects of double-oxygen vacancies. The defect structures of TiO2 surfaces strongly affect their adsorption and thermal/photodesorption behaviors. On the TiO2(001) surface, CH3OH and H2O dissociatively adsorb at the surface Ti sites near Ti interstitials; O2 molecularly adsorbs at the surface Ti sites adjacent to Ti interstitials, forming photoactive O2 species that undergoes a hole-mediated photodesorption process; CO adsorbs at the nearest surface Ti sites close to the Ti interstitials, but CO2 does not, and the resulting CO species is photoactive; and both CO and CO2 species adsorbed at the normal Ti4+ sites are photoinactive. On the TiO2(011)-(2 × 1) surface, O2 adsorbs only at the double-oxygen vacancy sites, and the resulting O2 species dissociates to form two oxygen atoms to refill in the oxygen vacancies upon heating; CO2 adsorbs at the double-oxygen vacancy sites, but CO does not, and the resulting CO2 species is photoactive; and both CO and CO2 species adsorbed at the surface Ti4+ sites are photoinactive. These results broaden the fundamental understandings of the chemistry and photochemistry of TiO2 surfaces, and the established structure-reactivity relation of small molecules on TiO2 surfaces is useful in probing complex structures of TiO2 powder catalysts.

10.
Insect Sci ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32039551

RESUMO

Swarming behavior facilitates pair formation, and therefore mating, in many eusocial termites. However, the physiological adjustments and morphological transformations of the flight muscles involved in flying and flightless insect forms are still unclear. Here, we found that the dispersal flight of the eusocial termite Reticulitermes chinensis Snyder led to a gradual decrease in ATP supply from oxidative phosphorylation, as well as a reduction in the activities of critical mitochondrial respiratory enzymes from preflight to dealation. Correspondingly, using three-dimensional reconstruction and transmission electron microscopy (TEM), the flight muscles were found to be gradually deteriorated during this process. In particular, two tergo-pleural muscles (IItpm5 and IIItpm5) necessary to adjust the rotation of wings for wing shedding behavior were present only in flying alates. These findings suggest that flight muscle systems varied in function and morphology to facilitate the swarming flight procedure, which sheds light on the important role of swarming in successful extension and fecundity of eusocial termites. This article is protected by copyright. All rights reserved.

11.
Expert Opin Ther Pat ; 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32077340

RESUMO

Introduction: Discoidin domain receptor 1 (DDR1) is a collagen-activated receptor tyrosine kinase. Upon collagen binding, DDR1 undergoes tyrosine autophosphorylation, which consequently triggers downstream genetic and cellular pathways and plays critical roles in regulation of cellular morphogenesis, differentiation, proliferation, adhesion, migration, and invasion. Increasing evidence suggests the potential roles of DDR1 in various human diseases including cancer, fibrosis, atherosclerosis, and other inflammatory disorders. Modulating the activity of DDR1 may be considered as a new therapeutic strategy for human cancer and inflammation-related diseases.Areas covered: This article summarizes current progress on the development of selective DDR1 inhibitors and their potential therapeutic application during the period from 2014 to 2019.Expert opinion: DDR1 is closely linked to a variety of human diseases, including fibrotic disorders, atherosclerosis, and cancer etc. Thus, DDR1 has been considered as a new potential target for drug discovery. A number of DDR1 inhibitors have been identified in the past 5 years, but most of them display relatively broad inhibition across the kinome. New generation DDR1 inhibitors targeting the allosteric sites outside of the canonical ATP-binding pocket or extracellular domain (allosteric inhibitors) may offer a new opportunity for selective DDR1 inhibition therapy development.

12.
Hypertension ; 75(3): 603-614, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32008462

RESUMO

Our objective was to gain insight in the calculation and interpretation of population health metrics that inform disease prevention. Using as model environmental exposure to lead (ELE), a global pollutant, we assessed population health metrics derived from the Third National Health and Nutrition Examination Survey (1988 to 1994), the GBD (Global Burden of Disease Study 2010), and the Organization for Economic Co-operation and Development. In the National Health and Nutrition Examination Survey, the hazard ratio relating mortality over 19.3 years of follow-up to a blood lead increase at baseline from 1.0 to 6.7 µg/dL (10th-90th percentile interval) was 1.37 (95% CI, 1.17-1.60). The population-attributable fraction of blood lead was 18.0% (10.9%-26.1%). The number of preventable ELE-related deaths in the United States would be 412 000 per year (250 000-598 000). In GBD 2010, deaths and disability-adjusted life-years globally lost due to ELE were 0.67 million (0.58-0.78 million) and 0.56% (0.47%-0.66%), respectively. According to the 2017 Organization for Economic Co-operation and Development statistics, ELE-related welfare costs were $1 676 224 million worldwide. Extrapolations from the foregoing metrics assumed causality and reversibility of the association between mortality and blood lead, which at present-day ELE levels in developed nations is not established. Other issues limiting the interpretation of ELE-related population health metrics are the inflation of relative risk based on outdated blood lead levels, not differentiating relative from absolute risk, clustering of risk factors and exposures within individuals, residual confounding, and disregarding noncardiovascular disease and immigration in national ELE-associated welfare estimates. In conclusion, this review highlights the importance of critical thinking in translating population health metrics into cost-effective preventive strategies.

13.
Artigo em Inglês | MEDLINE | ID: mdl-32078566

RESUMO

As an integral component of blind image deblurring, non-blind deconvolution removes image blur with a given blur kernel, which is essential but difficult due to the ill-posed nature of the inverse problem. The predominant approach is based on optimization subject to regularization functions that are either manually designed or learned from examples. Existing learning-based methods have shown superior restoration quality but are not practical enough due to their restricted and static model design. They solely focus on learning a prior and require to know the noise level for deconvolution. We address the gap between the optimization- and learning-based approaches by learning a universal gradient descent optimizer. We propose a recurrent gradient descent network (RGDN) by systematically incorporating deep neural networks into a fully parameterized gradient descent scheme. A hyperparameter-free update unit shared across steps is used to generate the updates from the current estimates based on a convolutional neural network. By training on diverse examples, the RGDN learns an implicit image prior and a universal update rule through recursive supervision. The learned optimizer can be repeatedly used to improve the quality of diverse degenerated observations. The proposed method possesses strong interpretability and high generalization. Extensive experiments on synthetic benchmarks and challenging real-world images demonstrate that the proposed deep optimization method is effective and robust to produce favorable results as well as practical for real-world image deblurring applications.

14.
J Environ Sci (China) ; 90: 297-309, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32081326

RESUMO

Increasing energy consumption in the transportation sector results in challenging greenhouse gas (GHG) emissions and environmental problems. This paper involved integrated assessments on GHG emissions and emergy of the life cycle for the internal combustion engine (ICE) and electric automobiles in the USA over the entire assumed fifteen-year lifetime. The hotspots of GHG emissions as well as emergy indices for the major processes of automobile life cycle within the defined system boundaries have been investigated. The potential strategies for reducing GHG emissions and emergy in the life cycle of both ICE and electric automobiles were further proposed. Based on the current results, the total GHG emissions from the life cycle of ICE automobiles are 4.48E + 07 kg CO2-e which is 320 times higher than that of the electric automobiles. The hotspot area of the GHG emissions from ICE and electric automobiles are operation phase and manufacturing process, respectively. Interesting results were observed that comparable total emergy of the ICE automobiles and electric automobiles have been calculated which were 1.54E + 17 and 2.20E + 17 sej, respectively. Analysis on emergy index evidenced a better environmental sustainability of electric automobiles than ICE automobiles over the life cycle due to its higher ESI. To the authors' knowledge, it is the first time to integrate the analysis of GHG emissions together with emergy in industrial area of automobile engineering. It is expected that the integration of emergy and GHG emissions analysis may provide a comprehensive perspective on eco-industrial sustainability of automobile engineering.

15.
Sci Rep ; 10(1): 3167, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081915

RESUMO

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that primarily affects the joints. Overweight and obesity can aggravate disease activity and clinical outcome in patients with RA. However, the role of bariatric surgery in inducing weight loss in the treatment of RA has not been confirmed. In this 12-month prospective cohort study, RA patients with obesity who were referred to our hospital were included. Thirty-two patients were classified into the bariatric surgery group according to the patient's decision after a comprehensive assessment of surgery indications, and 33 patients received only pharmacotherapy for RA. At the 12-month follow-up, the response rates of ACR20, ACR50 and ACR70 were 75.0% vs. 51.5%, 53.1% vs. 39.4% and 31.3% vs. 21.2% in the bariatric surgery and non-surgery groups, respectively (all p < 0.05); the mean DAS28-ESR, DAS28-CRP and cDAI scores were 1.5 ± 0.9 vs. 2.4 ± 1.4, 1.2 ± 0.9 vs. 2.2 ± 1.7 and 9.5 ± 6.8 vs. 15.8 ± 12.5, respectively, in surgical patients compared to non-surgical patients (all p < 0.05). Compared to baseline, after 12 months, a significant reduction was observed in the use of leflunomide, biological agents, combination treatments, and NSAIDs in both groups (p < 0.05 or p < 0.01). However, there was no difference in medication use between the 2 groups either at baseline or at the 12-month follow-up (all p > 0.05). Compared to non-surgical patients, in RA patients with obesity, weight loss after bariatric surgery was associated with lower disease activity. Medication tapering for RA in patients who underwent bariatric surgery was not superior to that in non-surgical patients.

16.
Med Phys ; 2020 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-31901143

RESUMO

PURPOSE: To apply an imaging metric of the structural SIMilarity (SSIM) index to the radiotherapy dose verification field and evaluate its capability to reveal the different types of errors between two dose distributions. METHOD: The SSIM index consists of three sub-indices: luminance, contrast, and structure. Given two images, luminance analysis compares the local mean result, contrast analysis compares the local standard deviation, and the structure index represents the local Pearson correlation. Three test error patterns (absolute dose error, dose gradient error, and dose structure error) were designed to characterize the response of SSIM and its sub-indices and establish the correlation between the indices and different dose error types. After establishing the correlation, four radiotherapy plans (one MLC picket-fence test plan, one brain stereotactic radiotherapy plan, and two head-and-neck plans) were tested by computing each index and compared with the gamma analysis results to determine their similarities and differences. RESULTS: Among the three test error patterns, the luminance index decreased from 1 to 0.1 when the absolute dose agreement fell from 100% to 5%, the contrast index decreased from 1 to 0.36 when the dose gradient agreement fell from 100% to 10%, and the structure index decreased from 1 to 0.23 when the periodical dose pattern shifted (leading to a lower correlation). Thus, the luminance, contrast and structure index can detect the absolute dose error, gradient discrepancy, and dose structure error, respectively. For the four clinical cases, the sub-indices can reveal the type of error when gamma analysis only provided limited information. CONCLUSIONS: The correlation between the subcomponents of the SSIM index and the error types of the dose distribution were established. The SSIM index provides additional error information compared to that provided by gamma analysis.

17.
Chem Commun (Camb) ; 56(10): 1553-1556, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31930267

RESUMO

An enantioselective (3+2) cycloaddition of enals and cyclic N-sulfonyl trifluoromethyl ketimines via N-heterocyclic carbene-catalyzed homoenolate addition is described. This reaction can efficiently construct fused N-heterocycle γ-lactams bearing two adjacent chiral centers with >20 : 1 dr and 94-99% ee, with one chiral center as a trifluoromethylated α-tetrasubstituted carbon stereocenter.

18.
Ying Yong Sheng Tai Xue Bao ; 31(1): 309-318, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-31957409

RESUMO

Procambarus clarkii was introduced into China as an important aquatic product in early 20th century. It has characteristics of high fertility, rapid growth, adaptability and digging burrows, which could cause damage of crops, cropland and facilities, decrease local biodiversity and thus threaten local ecosystem. Thus, predicting the potential distribution of P. clarkii in response to climate change was essential for preventing and monitoring this species. Based on the distribution of P. clarkii, the maximum entropy (MaxEnt) and genetic algorithm for rule-set production (GARP) models were used to predict its distribution in China under current climate and four climate scenarios (RCP 2.6, RCP 4.5, RCP 6.0, RCP 8.5) in two periods, 2041-2060 and 2061-2080. Then, the modeling results were tested by ROC curves. The results showed that under current climate, the highly suitable region for distribution predicted by the MaxEnt and GARP models were Shanghai, Jiangsu, Zhejiang and Anhui along the Yangtze River. The main environmental variables affecting its distribution were mean temperature of the coldest quarter, minimum temperature of the warmest month, and temperature seasonality, maximum temperature of the warmest month, precipitation of the driest month. Under the future climate scenarios, the suitable area of P. clarkii distribution varied in 2061-2080. The total suitable area of P. clarkii would increase under RCP2.6 and RCP 4.5, whereas under RCP 8.5 the suitable area of P. clarkii would increase, and then decrease. In RCP 6.0, there was no change. The suitable areas of P. clarkii would disperse to different latitude areas and migrate toward high altitude.


Assuntos
Ecossistema , Espécies Introduzidas , Animais , Astacoidea , China , Mudança Climática
19.
Sci Immunol ; 5(43)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31953257

RESUMO

Cytokine release syndrome (CRS) counteracts the effectiveness of chimeric antigen receptor (CAR) T cell therapy in cancer patients, but the mechanism underlying CRS remains unclear. Here, we show that tumor cell pyroptosis triggers CRS during CAR T cell therapy. We find that CAR T cells rapidly activate caspase 3 in target cells through release of granzyme B. The latter cleaves gasdermin E (GSDME), a pore-forming protein highly expressed in B leukemic and other target cells, which results in extensive pyroptosis. Consequently, pyroptosis-released factors activate caspase 1 for GSDMD cleavage in macrophages, which results in the release of cytokines and subsequent CRS. Knocking out GSDME, depleting macrophages, or inhibiting caspase 1 eliminates CRS occurrence in mouse models. In patients, GSDME and lactate dehydrogenase levels are correlated with the severity of CRS. Notably, we find that the quantity of perforin/granzyme B used by CAR T cells rather than existing CD8+ T cells is critical for CAR T cells to induce target cell pyroptosis.

20.
ACS Appl Mater Interfaces ; 12(4): 4895-4905, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31898463

RESUMO

Flexible, lightweight, robust, and multifunctional characteristics are greatly desirable for next-generation wearable electromagnetic interference (EMI) shielding materials. In this work, an alternating multilayered structure with robust polymer frame layers and directly contacted conducting layers was designed to prepare high-performance EMI films. Especially, the multilayered films containing alternating cellulose nanofiber (CNF) layers and MXene layers are fabricated via a facile and efficient alternating vacuum filtration approach. Deriving from the mechanical frame effect acted by CNF layers in, which is capable of preventing the nanosized "zigzag" crack in MXene layers from growing to the whole film, the alternating multilayered film (CNF@MXene) revealed the improved mechanical strength (112.5 MPa) and toughness (2.7 MJ m-3) compared to both freestanding MXene film and homogeneous CNF/MXene film. Meanwhile, the directly contacted MXene layers resulted in the increased electrical conductivity from 2 (homogeneous CNF/MXene film) to 621-82 S m-1 (CNF@MXene films). In conjunction with the extra "reflection-absorption-zigzag reflection" mechanism among the alternating multilayers, CNF@MXene films demonstrated an exceptional EMI shielding effectiveness of ∼40 dB in the X-band and K-band and high specific shielding effectiveness up to 7029 dB cm2 g-1 at a thickness of only 0.035 mm. Besides, the excellent mechanical flexibility ensured the stable EMI shielding and electrical properties, which can withstand the folding test more than 1000 times without obvious reduction. Moreover, the excellent electrical conductivity endows the alternating multilayered film with an outstanding and steady Joule heating performance, which could reach more than 100 °C at only 6 V impressed voltage to within 10 s. As a result, our alternating multilayered film with reinforced EMI shielding and Joule heating performance is promising in the next-generation intelligent protection devices applying in cold and complex practical environments.

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