MnO2 porous carbon composite from cellulose enabling high gravimetric/volumetric performance for supercapacitor.

Preparing electrode material integrated with high gravimetric/volumetric capacitance and fast electron/ion transfer is crucial for the practical application. Owing to the structural contradiction, it is a big challenge to construct electrode material with high packing density, sufficient ion transport channels, and fast electronic transfer pathways. Herein, MnO2 porous carbon composite with abundant porous structure and 3D carbon skeleton was facilely fabricated from Linum usitatissimum. L stems via NaOH activation and MnO2 introduction. The in-situ introduced MnO2 not only increases the packing density and the electrical conductivity of the porous carbon but also provides more active sites for oxidation reactions. These unique characteristics endow the resultant MnO2 porous carbon composite with remarkable gravimetric capacitance of 549 F g-1, volumetric capacitance of 378 F cm-3, and capacitance retention of 54.9 %. Giving the simple process and low cost, this work might offer a new approach for structural design and the practical application of high-performance electrode materials.

Corrigendum: Effects of meteorological factors and atmospheric pollution on hand, foot, and mouth disease in Urumqi Region.

[This corrects the article DOI: 10.3389/fpubh.2022.913169.].

Effects of Meteorological Factors and Atmospheric Pollution on Hand, Foot, and Mouth Disease in Urumqi Region.

Background: Hand, foot, and mouth disease (HFMD) is a febrile rash infection caused by enteroviruses, spreading mainly via the respiratory tract and close contact. In the past two decades, HFMD has been prevalent mainly in Asia, including China and South Korea, causing a huge disease burden and putting the lives and health of children at risk. Therefore, a further study of the factors influencing HFMD incidences has far-reaching implications. In existing studies, the environmental factors affecting such incidences are mainly divided into two categories: meteorological and air. Among these studies, the former are the majority of studies on HFMD. Some scholars have studied both factors at the same, but the number is not large and the findings are quite different. Methods: We collect monthly cases of HFMD in children, meteorological factors and atmospheric pollution in Urumqi from 2014 to 2020. Trend plots are used to understand the approximate trends between meteorological factors, atmospheric pollution and the number of HFMD cases. The association between meteorological factors, atmospheric pollution and the incidence of HFMD in the Urumqi region of northwest China is then investigated using multiple regression models. Results: A total of 16,168 cases in children are included in this study. According to trend plots, the incidence of HFMD shows a clear seasonal pattern, with O3 (ug/m3) and temperature (°C) showing approximately the same trend as the number of HFMD cases, while AQI, PM2.5 (ug/m3), PM10 (ug/m3) and NO2 (ug/m3) all show approximately opposite trends to the number of HFMD cases. Based on multiple regression results, O3 (P = 0.001) and average station pressure (P = 0.037) are significantly and negatively associated with HFMD incidences, while SO2 (P = 0.102), average dew point temperature (P = 0.072), hail (P = 0.077), and thunder (P = 0.14) have weak significant relationships with them.

Three-dimensional macroporous hybrid carbon aerogel with heterogeneous structure derived from MXene/cellulose aerogel for absorption-dominant electromagnetic interference shielding and excellent thermal insulation performance.

The development of electromagnetic interference (EMI) shielding materials with excellent absorption coefficient (A) is vital to completely eliminate the pollution of the ever-increasing electromagnetic waves (EMWs). In this regard, a TiC/carbon hybrid aerogel, derived from MXene/cellulose aerogel, was successfully fabricated via freeze-drying and subsequent pyrolysis process. Profiting from the open, loose three-dimensional (3D) macro pores with sheet-like morphology and high porosity, as well as the rich heterogeneous interfaces between TiC and cellulose-derived carbon, the as-prepared hybrid carbon aerogel achieves ultra-efficient EMI shielding effectiveness of 72.9 dB in conjunction with a superior A value of 0.76 and low thermal conductivity. These properties endow the as-prepared aerogel with strong absorption-dominant ultra-efficient EMI shielding and thermal insulation performance to meet the complex practical requirements. This work provides a promising strategy for achieving ultra-efficient multifunctional EMI shielding performance and superior A simultaneously.

Flexible and Anisotropic Strain Sensors with the Asymmetrical Cross-Conducting Network for Versatile Bio-Mechanical Signal Recognition.

Flexible strain sensors with high performance are actively and widely investigated for wearable electronic devices. However, the conventional sensors often suffer from a lack of detection of complex multidimensional strain, which severely limits their wide applications. To overcome this critical challenge, we propose a pattern design by screen printing to construct an asymmetrical cross-conductive network in the piezoresistive strain sensor, which can enhance the response to external stimuli in different directions. The unique network endows the prepared sensors with the excellent ability of instantaneous detection and accurate identification of multidimensional strains. Moreover, the sensor also demonstrates high sensitivity, fast response, an ultra-wide sensing range, and excellent stability and durability. Benefiting from the outstanding comprehensive performance of the prepared sensor, a full range of human actions (wink, smile, swallowing, and joint bending) and subtle bio-signals (pulse and breathing) are easily and accurately monitored. A wireless wearable device assembled by the sensor shows great potential applications in practical real-time physiological monitoring and intelligent mobile diagnosis for humans. This work provides an innovative and effective strategy for manufacturing flexible and multifunctional strain sensors to fully satisfy versatile applications of new-generation wearable electronic devices.

Improving the anti-tumor effect of genistein with a biocompatible superparamagnetic drug delivery system.

The practical application of genistein as a low toxicity chemotherapeutic drug is hindered by many of its in vivo properties. To overcome these obstacles, a new multifunctional drug delivery system is developed, which is based on covalently attaching genistein onto Fe3O4 nanoparticles coated by cross-linked carboxymethylated chitosan (CMCH). The structure of the Fe3O4-CMCH-genistein nano-conjugate was confirmed by transmission electron micrographs (TEM), X-ray diffraction (XRD) and Fourier-transfer infrared (FT-IR) spectroscopy. The nano-conjugate shows good water solubility and superparamagnetic properties with a saturation magnetization of 55.1 emu/g. The effects of free genistein and FeO4-CMCH-genistein nano-conjugate on the proliferation and apoptosis of gastric cancer cell line SGC-7901 were investigated by MTT assay and flow cytometry (FACS). MTT results indicate that the Fe3O4-CMCH-genistein nano-conjugate exhibits a significantly enhanced inhibition effect to the SGC-7901 cancer cells than the free genistein. FACS data suggests that the inhibition on cell proliferation of the nano-conjugate is related with an induced apoptosis process. This drug delivery system is promising for future multifunctional chemotherapeutic application that combines drug release and magnetic hyperthermia therapy.

Facile synthesis of trimethylammonium grafted cellulose foams with high capacity for selective adsorption of anionic dyes from water.

The increasing amount of dye discharge is imposing more stringent requirements on dye removal than ever before. In this work, a three-dimensional network structured cationic cellulose foam (CCF) with high dye adsorption capability and highly selective adsorption of anionic dyes is prepared through grafting and chemical crosslinking. It exhibits a maximum anionic dye Eosin Y (EY) adsorption capacity of 364.22 mg/g and a corresponding removal efficiency as high as 99.58 %. Besides, results indicate that the obtained CCF displays superior adsorption capability for anionic dyes, environmental adaptability, as well as high recyclability. The isothermal and kinetics of the dye adsorption highly match Langmuir and the pseudo-second-order kinetic model, suggesting that anionic dyes are absorbed on CCF through chemical and monolayer action. All these merits demonstrate a simple, feasible and effective approach for the design and fabrication of cellulose foams with selective adsorption of anionic dyes from wastewater.

pH-sensitive magnetic drug delivery system via layer-by-layer self-assembly of CS/PEG and its controlled release of DOX.

Cancer is one of the biggest killers threat to human life and health and is still difficult to treat mainly due to the lack of targeted drug delivery stages and limitations associated with delivering drugs to targeted cancer tissues. The goal of this work was to develop a magnetic, pH-sensitive formulation for targeted delivery of chemotherapeutic agents to cancer cells. Then the functional drug delivery system (Fe3O4@CS/PEG-DOX) was synthesized by the layer-by-layer (LbL) self-assembly technique. And the drug loading content is calculated to be 19.1%. In addition, the Fe3O4@CS/PEG-DOX exhibited excellent pH-sensitivity, 73.1% DOX was released within 48 h at pH 4.0. Furthermore, all the release behaviors fit the Higuchi model very well and the dissolution of CS/PEG layers played a key role on DOX release from Fe3O4@CS/PEG-DOX. The results of toxicity analysis in human liver hepatocellular carcinoma cells (HepG2) revealed that Fe3O4@CS/PEG-DOX exhibited high anti-tumor activity, while the Fe3O4@CS/PEG nanocomposites were practically non-toxic. Therefore, all the results demonstrated that the Fe3O4@CS/PEG-DOX could have an important impact on the development of targeted intracellular delivery nanodevices for cancer therapy.

Stiff micelle-crosslinked hyaluronate hydrogels with low swelling for potential cartilage repair.

Pluronic F127 diacrylate (F127DA) nano-micelle crosslinked methacrylated hyaluronic acid (MeHA) hydrogels (NMgels) with strong compressive properties have been demonstrated in our previous study. The current study further focuses on how the F127DA micelles and long-term swelling affect the mechanical performance of hydrogels from the view of in vitro/in vivo applications. Co-contributions of the F127DA micelles and MeHA to the compression performance are first investigated through mechanical analysis and cyclic loading/unloading tests before and after swelling. The optimized NMgel with F127DA micelles of 15 wt% and MeHA of 1.5 wt% (F15H1.5) exhibits a low swelling ratio and a well-maintained network in pH = 7.4 phosphate buffered saline. The abundant hydration significantly affects the initial mechanical properties of the hydrogels. After swelling, the compressive strength, modulus and fracture energy of F15H1.5 NMgel decrease from ∼3.44 MPa, ∼312 kPa and ∼407.5 kJ m-3 to 0.59 MPa, ∼55 kPa, and ∼81.8 kJ m-3, respectively. The energy dissipation of the first loading-unloading cycle dramatically decreases from ∼21.5 kJ m-3 to ∼6.0 kJ m-3 as well. Nevertheless, the gel still retains excellent stiffness, toughness and self-recovery due to the dense and strong micelle linkages. In vivo studies show that the implantation of F15H1.5 hydrogel in thyroid cartilage defects of rabbit larynx effectively promotes the regeneration of cartilage after 8 weeks. These results indicate that the stiff NMgel is a promising cartilage tissue engineering scaffold for the regeneration of cartilage in vivo.

[Peg-interferon alfa-2a and highly active antiretroviral drug therapy on hepatitis C patients with AIDS].

OBJECTIVE: To evaluate the clinical effect and side-effect of peg-interferon alfa-2a (PEG-IFN alfa-2a) and highly active antiretroviral therapy (HAART) for patients infected with hepatitis C virus (HCV) and co-infected with human immunodeficiency virus (HIV). METHODS: Twenty-two patients with HCV/HIV co-infection received highly active antiretroviral therapy initially; after their CD4 lymphocyte counts rose to over 0.20x10(9)/L, they were separated into two groups: one group with CD4 lymphocytes over 0.35x10(9)/L (high group) and one group with CD4 lymphocytes below 0.35x10(9)/L (low group). Both groups were given 180 microg of PEG-IFN alfa-2a every week intramuscularly. HCV RNA and HIV RNA loads, blood cell and CD4 lymphocyte counts, and liver functions were routinely examined. RESULTS: After 12, 24 and 48 weeks of PEG-IFN alfa-2a therapy, mean HCV RNA loads reduced 2.0650 log10 copies/ml (t=3.8733), 2.9146 log10 copies/ml (t=7.6741) and 2.4315 log10 copies/ml (t=5.8202) from the baseline at week 0 in the 13 patients in the high group, and reduced 1.1522 log10 copies/ml (t = 2.8937), 1.4189 log10 copies/ml (t=2.4422) and 1.1167 log10 (t=1.1261) in the 8 patients of the low group. However, there was no significant difference between the early viral response rate (EVR) and the end of treatment viral response rate (ETVR) of the two groups. In the high group, the white blood cell count was lower at 24 weeks than the base line (t=2.4700), and the blood platelet count was lower both at 24 and 48 weeks than the base line (t=2.3273 and t=3.6149). CONCLUSIONS: PEG-IFN alfa-2a can effectively reduce HCV RNA loads in patients with HCV-/HIV co-infection, and the inhibition rate in patients with higher CD4 lymphocyte counts is better. The EVR and ETVR of the two groups of patients show similar results after the treatment. PEG-IFN alfa-2a can reduce the white blood cell counts and the blood platelet counts in the peripheral blood.