To overcome the safety hazard of the liquid electrolytes used in traditional lithium batteries, solid electrolytes have drawn more attention because of their advantages such as non-volatility, easy ...processing, good mechanical properties, and stability. In this paper, sodium alginate (SA) nanofiber membranes were used as the backbone of PEO-based solid electrolytes. SA nanofiber membranes were prepared by electrospinning with assistance from PEO and cross-linked with calcium ions to construct a nanofiber network skeleton, which provided a guarantee for the stability of the subsequent electrolyte preparation process. The effects of spinning conditions and crosslinking time on the structure and performances of the nanofiber membranes were investigated. Meanwhile, the relationship between the skeleton of nanofiber membranes cross-linked with calcium ions and ion conductivity was investigated. The optimal parameters of the electrospinning process including concentration, voltage, distance, and SA content were discussed, and the fiber diameter and its distribution were analyzed. Furthermore, Fourier transform infrared (FTIR) spectrometer, thermal gravimetric analyzer analysis (TGA), X-ray diffraction (XRD), and energy dispersive spectrometer (EDS) maps were used to characterize the nanofiber membranes and electrolytes. The results showed that the thermal performance of cross-linked nanofiber membranes improved and the crystallinity of the PEO matrix decreased. The ion conductivity of the electrolytes was characterized by electrochemical impedance spectroscopy (EIS) testing, and the results showed that the assembled lithium symmetric battery had a good ion conductivity of 6.82 × 10−5 S/cm at 30 °C.
Bacterial cellulose (BC) is widely used in various fields due to its excellent physicochemical properties. However, the main drawback is its high production cost. The present research exploited the ...preparation of BC by combining the hydrothermal process using acetic acid and enzyme treatment for the hydrolysis of corncob. The BC production was further improved by optimizing the key factors. The concentration of reducing sugar was 22.7 g/L after thermohydrolysis at 180 °C for 80 min and enzyme hydrolysis in 6 U/mL cellulase buffer solution for 24 h. It supported about 1.36 g/L as the sole culture medium, which was 5.6 times more than corncob hydrolysate without detoxification (0.25 g/L) and more than Hestrin-Schramm (HS) standard medium (1.12 g/L). The BC products were characterized by FT-IR spectroscopy, XRD, TG, and SEM analysis. Compared to the BC produced by HS medium, the morphology of BC produced by detoxification corncob hydrolysate showed a lower value of the coefficient of variation (37.59%) and higher mean diameter (55.23 nm). XRD data showed higher crystallinity (77.50%) and TG analysis showed high thermal stability. The current study demonstrated that corncob is a promising carbon source for the sustainable production of BC.
Bacterial cellulose (BC) has been widely applied in various fields due to its excellent physicochemical properties, but its high production cost remains a challenge. Herein, the present study aimed ...to utilize the hydrolysate of vinegar residue (VR) as the only medium to realize the cost-effective production of BC. The BC production was optimized by the single-factor test. The treatment of 6 % VR concentration with 3 % acid concentration at 100 °C for 1.5 h and 96 U/mL of cellulase for 4 h at 50 °C obtained a maximum reducing sugar concentration of about 32 g/L. Additionally, the VR hydrolysate treated with 3 % active carbon (AC) at 40 °C for 0.5 h achieved a total phenol removal ratio of 86 %. The yield of BC reached 2.1 g/L under the optimum conditions, which was twice compared to the standard medium. The produced BC was characterized by SEM, FT-IR, XRD, and TGA analyses, and the results indicated that the BC prepared by AC-treated VR hydrolysate had higher fiber density, higher crystallinity, and good thermal stability. Furthermore, the regenerated BC (RBC) fibers with a tensile stress of 400 MPa were prepared successfully using AmimCl solution as a solvent by dry-wet-spinning method. Overall, the VR waste could be used as an alternative carbon source for the sustainable production of BC, which could be further applied to RBC fibers preparation.
Since the fire hazards of polyester-cotton blended (PTCO) fabrics and the hidden dangers of bacterial infection concerns caused by the contained cotton fiber, the design of flame retardant and ...antibacterial PTCO fabrics has received considerable attention. In this work, flame-retardant PTCO fabrics with satisfactory antibacterial properties were fabricated via a convenient and eco-friendly impregnation treatment involving guanidine phosphate (GP) and polyethylenimine (PEI). The prepared PTCO fabrics demonstrated excellent flame retardancy with a high limiting oxygen index value of 30.5 % and self-extinguishing capability, the damaged length was only 34 mm in the vertical flammability test. Furthermore, the peak heat release rate and the total heat release of coated PTCO fabrics were reduced significantly by 49 % and 38 %, respectively, indicating a substantial enhancement in fire safety. According to the analysis of the char residues and volatiles, GP presented great catalytic carbonization property, and PEI assisted the formation of the dense and stable carbon layer. The stable carbon layer effectively restricted mass and oxygen transfer between the PTCO fabrics and the environment. In addition, the introduction of PEI also produced more nonflammable gases to enhance the flame retardancy of the PTCO fabrics. Importantly, the GP/PEI coating barely deteriorate the physical and mechanical properties of the PTCO fabrics. The antibacterial rate of the GP/PEI-coated PTCO fabrics against Escherichia coli and Staphylococcus aureus was 99.99 %, similar to that of GP-coated fabrics, indicating the efficacy antibacterial properties of GP, and the addition of PEI did not compromise the antibacterial properties of GP. This work offers an efficient and simple approach to producing multifunctional PTCO fabrics with excellent flame retardancy and antibacterial properties, which are hopeful to expand the promising application of PTCO fabrics.
•Guanidine phosphate and polyethylenimine coating were constructed on polyester-cotton blend fabrics.•The coating imparts efficient flame retardancy and antibacterial properties to polyester-cotton blend fabrics•The LOI of coated fabric reached 30.5 % and the “scaffolding effect” was eliminated.•The coated fabrics exhibited flame-retardant activities in both condensed and gaseous phases during combustion.•The antibacterial rates of the coated PTCO fabrics against E. coli and S. aureus were 99.99 %.
Context
While Au-based catalysts recently have shown tremendous potential in glucose oxidation to gluconic acid, the detailed reaction mechanism is still unclear, which impedes the development of ...direct glucose fuel cell (DGFC).
Methods
Using density functional theory (DFT), we exhibit some new adsorption configurations and oxidation mechanisms by considering both the open chain form and the ring form of glucose on Au(111) surface in the presence of OH. The strong interactions between glucose and the OH adsorbed surface are obtained. Moreover, form the calculated energy pathways, the oxidation of glucose in the open chain involves the dissociation of the formyl C − H bond by the adsorbed OH, while the ring form glucose oxidation is initiated by O − H bond rupture rather than C − H bond scission and preferentially undergoes the ring-open process to generate the open chain form glucose. Meanwhile, the results demonstrate that the adsorbed OH assists in reducing the activation energy of reaction process.
Despite the rapid progress of the global economy and technology's key role, severe environmental and ecological challenges must be given proper attention to advance sustainable development. This ...paper uses the autoregressive distributed lag method on 40 years of data to investigate the impact of technological innovation on China's sustainable development and determine the channels through which technological innovation contributes to sustainable development. Our empirical results demonstrate that technological innovation is an important driver in promoting sustainable development, revealing that innovation adds to economic growth without harmful effects on the environment. The results also indicate that financial development significantly adds to China's sustainable development through carbon dioxide (CO2) emissions reduction, and economic growth further triggers the sustainability process by reducing CO2 emissions. The findings of this paper enhance existing theories and contribute to the progress of sustainable development in China, the novel results outlining industry development drivers could potentially be used for developing global innovation policies integration.
•We examine the effects of technological innovation on China's sustainable development.•We determine the channels through which technological innovation influences sustainability.•The results reveal that technological innovation has a positive impact on sustainability.•Technological innovation is correlated with raising economic growth and lowering environmental pollution.•Financial development advances sustainability by reducing environmental pollution.
Hyperpolarization-activated cAMP-regulated (HCN) channels play important physiological roles in both cardiovascular and central nervous systems. Among the four HCN isoforms, HCN2 and HCN4 show high ...expression levels in the human heart, with HCN4 being the major cardiac isoform. The previously published crystal structure of the mouse HCN2 (mHCN2) C-terminal fragment, including the C-linker and the cyclic-nucleotide binding domain (CNBD), has provided many insights into cAMP-dependent gating in HCN channels. However, structures of other mammalian HCN channel isoforms have been lacking. Here we used a combination of approaches including structural biology, biochemistry, and electrophysiology to study cAMP-dependent gating in HCN4 channel. First we solved the crystal structure of the C-terminal fragment of human HCN4 (hHCN4) channel at 2.4 Å. Overall we observed a high similarity between mHCN2 and hHCN4 crystal structures. Functional comparison between two isoforms revealed that compared with mHCN2, the hHCN4 protein exhibited marked different contributions to channel function, such as a ∼3-fold reduction in the response to cAMP. Guided by structural differences in the loop region between β4 and β5 strands, we identified residues that could partially account for the differences in response to cAMP between mHCN2 and hHCN4 proteins. Moreover, upon cAMP binding, the hHCN4 C-terminal protein exerts a much prolonged effect in channel deactivation that could have significant physiological contributions.
Salmonella is one of the most common Gram-negative pathogens and seriously threatens chicken farms and food safety. This study aimed to establish a multiplex polymerase chain reaction (PCR) approach ...for the identification of different Salmonella enterica subsp. enterica. The citE2 gene and interval sequence of SPS4_00301–SPS4_00311 existed in all S. enterica subsp. enterica serovars by genomic comparison. By contrast, a 76 bp deletion in citE2 was found only in Salmonella Pullorum. Two pairs of special primers designed from citE2 and interval sequence were used to establish the multiplex PCR system. The optimized multiplex PCR system could distinguish Salmonella Pullorum and non-Salmonella Pullorum. The sensitivity of the optimized multiplex PCR system could be as low as 6.25 pg/μL and 104 colony-forming units (CFU)/mL for genomic DNA and Salmonella Pullorum cells, respectively. The developed multiplex PCR assay distinguished Salmonella Pullorum from 33 different Salmonella enterica subsp. enterica serotypes and 13 non-target species. The detection of egg samples artificially contaminated with Salmonella Pullorum, Salmonella Enteritidis, and naturally contaminated 69 anal swab samples showed that results were consistent with the culture method. These features indicated that the developed multiplex PCR system had high sensitivity and specificity and could be used for the accurate detection of Salmonella Pullorum in clinical samples.
Dysfunctional p53 signaling is one of the major causes of hepatocellular carcinoma (HCC) tumorigenesis and development, but the mechanisms underlying p53 inactivation in HCC have not been fully ...clarified. The role of Krüppel-associated box (KRAB)-type zinc-finger protein ZNF498 in tumorigenesis and the underlying mechanisms are poorly understood.
Clinical HCC samples were used to assess the association of ZNF498 expression with clinicopathological characteristics and patient outcomes. A mouse model in which HCC was induced by diethylnitrosamine (DEN) was used to explore the role of ZNF498 in HCC initiation and progression. ZNF498 overexpression and knockdown HCC cell lines were employed to examine the effects of ZNF498 on cellular proliferation, apoptosis, ferroptosis and tumor growth. Western blotting, immunoprecipitation, qPCR, luciferase assays and flow cytometry were also conducted to determine the underlying mechanisms related to ZNF498 function.
ZNF498 was found to be highly expressed in HCC, and increased ZNF498 expression was positively correlated with advanced pathological grade and poor survival in HCC patients. Furthermore, ZNF498 promoted DEN-induced hepatocarcinogenesis and progression in mice. Mechanistically, ZNF498 directly interacted with p53 and suppressed p53 transcriptional activation by inhibiting p53 Ser46 phosphorylation. ZNF498 competed with p53INP1 for p53 binding and suppressed PKCδ- and p53INP1-mediated p53 Ser46 phosphorylation. In addition, functional assays revealed that ZNF498 promoted liver cancer cell growth in vivo and in vitro in a p53-dependent manner. Moreover, ZNF498 inhibited p53-mediated apoptosis and ferroptosis by attenuating p53 Ser46 phosphorylation.
Our results strongly suggest that ZNF498 suppresses apoptosis and ferroptosis by attenuating p53 Ser46 phosphorylation in hepatocellular carcinogenesis, revealing a novel ZNF498-PKCδ-p53INP1-p53 axis in HCC cells that would enrich the non-mutation p53-inactivating mechanisms in HCC.
Stem cell factor (SCF) and hypoxia-inducible factor-1α (HIF-1α) both have important functions in pancreatic ductal adenocarcinoma (PDAC). This study aims to analyze the expression and ...clinicopathological significance of SCF and HIF-1α in PDAC specimens and explore the molecular mechanism at PDAC cells in vitro and in vivo. We showed that the expression of SCF was significantly correlated with HIF-1α expression via Western blot, PCR, chromatin immunoprecipitation (ChIP) assay, and luciferase assay analysis. The SCF level was also correlated with lymph node metastasis and the pathological tumor node metastasis (pTNM) stage in PDAC samples. The SCF higher-expression group had significantly lower survival rates than the SCF lower-expression group (p<0.05). Hypoxia up-regulated the expression of SCF through the hypoxia-inducible factor (HIF)-1α in PDAC cells at the protein and RNA levels. When HIF-1α was knocked down by RNA interference, the SCF level decreased significantly. Additionally, ChIP and luciferase results demonstrated that HIF-1α can directly bind to the hypoxia response element (HRE) region of the SCF promoter and activate the SCF transcription under hypoxia. The results of colony formation, cell scratch, and transwell migration assay showed that SCF promoted the proliferation and invasion of PANC-1 cells under hypoxia. Furthermore, the down-regulated ability of cell proliferation and invasion following HIF-1α knockdown was rescued by adding exogenous SCF under hypoxia in vitro. Finally, when the HIF-1α expression was inhibited by digoxin, the tumor volume and the SCF level decreased, thereby proving the relationship between HIF-1α and SCF in vivo. In conclusion, SCF is an important factor for the growth of PDAC. In our experiments, we proved that SCF, a downstream gene of HIF-1α, can promote the development of PDAC under hypoxia. Thus, SCF might be a potential therapeutic target for PDAC.
PDF
