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Few studies have reported the application of vacuum‐sealing drainage of infected dialysis vascular access wounds. Herein, we present a case of buttonhole‐related arteriovenous fistula infection treated with vacuum‐sealing drainage. A 53‐year‐old female hemodialysis patient was hospitalized with an inflamed arteriovenous fistula. The patient underwent non‐tunneled catheterization for dialysis and was treated with moxifloxacin and vancomycin for staphylococcal infection. On Day 3, the skin overlying the inflamed fistula was ulcerated, resulting in severe hemorrhage. Emergency surgery was performed along with vacuum‐sealing drainage for fistula reconstruction. Vacuum‐sealing drainage accelerated the recovery of the wound without complications. No further access complications occurred during over a 3‐year follow‐up. [ABSTRACT FROM AUTHOR]

Background: IgA nephropathy (IgAN) is the most common cause of primary glomerulonephritis, with complex pathogenic mechanisms involving abnormal B-cell activation. As a novel biologic agent, telitacicept inhibits both B-lymphocyte stimulating factor and a proliferation-inducing ligand. It also inhibits both B cells and plasma cells and the production of galactose-deficient IgA1 (Gd-IgA1) and its autoantibodies, thus exerting an immunosuppressive effect. Women with IgAN are at a higher risk of adverse pregnancy outcomes such as preeclampsia and miscarriage, especially those with uncontrolled massive proteinuria and advanced chronic kidney disease. Therefore, IgAN disease control before and during pregnancy is essential. Here, we report the case of a woman with IgAN who had a successful pregnancy with significant improvement and long-term remission after treatment with telitacicept. This is the first report of a pregnancy following exposure to telitacicept. Case report. Conclusion: This report describes the efficacy of telitacicept in patients with IgAN and explores its value in women of childbearing age, suggesting effective and safe treatment options for women who wish to conceive. [ABSTRACT FROM AUTHOR]

A series of conjugated polymers bearing thiophene‐based donors and pyromellitic diimide (PMDI) acceptor were prepared, and their electrochromic (EC) properties were studied via using fabricated thin‐film EC devices. It was observed that structurally regular alternating polymers with fewer (1 and 2) thiophene donors do not exhibit any EC properties while increasing the number of donors eventually led to the emergence of orange‐red‐to‐green colour switching. On this basis, two more random co‐polymers containing higher donor‐to‐acceptor ratios were synthesized to further improve EC switching properties. The two polymers, which bear a PMDI‐to‐thiophene ratio of ca. 1 : 7 and 1 : 8, revealed orange red‐to‐blue colour switching and generally improved optical contrasts and switching speeds in both the visible and near infra‐red (NIR) region. In addition, the subtle modulation of polymer colour and hue via variation of the number of thiophene donors was evident through colorimetric study. This work therefore demonstrates the potential and possibility of using the PMDI acceptor unit to construct EC‐active conjugated polymers, and considerations for future tuning of colour and switching performances. [ABSTRACT FROM AUTHOR]

Fe–N–C catalysts are emerging as promising alternatives to Pt‐based catalysts for the oxygen reduction reaction (ORR), while they still suffer from sluggish reaction kinetics due to the discontented binding affinity between the Fe‐N4 sites and oxygen‐containing intermediates, and unsatisfactory stability. Herein, a flexible multichannel carbon fiber membrane immobilized with atomically dispersed Fe‐N4 sites and neighboring Fe nanoclusters/nanoparticles (FeN4‐FeNCP@MCF) is synthesized. The optimized geometric and electronic structures of the Fe atomic sites brought by adjacent Fe nanoclusters/nanoparticles and hierarchically porous structure of the carbon matrix endow FeN4‐FeNCP@MCF with outstanding ORR activity and stability, considerably outperforming its counterpart with FeN4 sites only and the commercial Pt/C catalyst. Liquid and solid‐state flexible zinc–air batteries employing FeN4‐FeNCP@MCF both exhibit outstanding durability. Theoretical calculation reveals that the Fe nanoclusters can trigger remarkable electron redistribution of the FeN4 sites and modulate the hybridization of central Fe 3d and O 2p orbitals, facilitating the activation of O2 molecules and optimizing the adsorption capacity of oxygen‐containing intermediates on FeN4 sites, and thus accelerating the ORR kinetic. This work offers an effective approach to constructing coupling catalysts that have single atoms coexisting with nanoclusters/nanoparticles for efficient ORR catalysis. [ABSTRACT FROM AUTHOR]

Objective: Secondary hyperparathyroidism (SHPT) is a common complication of chronic kidney disease (CKD). Hungry bone syndrome (HBS) after parathyroidectomy (PTX) is a serious complication, which can lead to diarrhea, convulsion, arrhythmia and even death. This study was aimed to determine the risk factors for HBS after PTX in dialysis patients with SHPT and construct a nomogram prediction model to predict the incidence of postoperative complications. Methods: Clinical data were collected from 80 maintenance hemodialysis (MHD) patients with SHPT who received total PTX in the Second Hospital of Jilin University from January 2018 to September 2021. In line with the inclusion and exclusion criteria, totally 75 patients were finally enrolled for analysis. Patients were divided into two groups for retrospective analysis according to the severity of postoperative HBS, including HBS group and non-HBS (N-HBS) group. Univariate and multivariate logistic regression analyses were conducted to determine the risk factors for postoperative HBS. Afterwards, the receiver operating characteristic (ROC) curves were plotted based on the statistical analysis results, aiming to compare the prediction effects of different predicting factors. Finally, the nomogram was established to evaluate the occurrence probability of postoperative complications predicted by the risk factors. Results: Among the 75 patients, 32 had HBS (HBS group), while 43 did not have HBS (N-HBS group). Univariate analysis results indicated that, the preoperative intact parathyroid hormone (iPTH) and serum alkaline phosphatase (ALP) levels in HBS group were significantly higher than those in N-HBS group, while preoperative hemoglobin and preoperative albumin (Alb) levels were significantly lower than those in N-HBS group. As discovered by multivariate logistic regression analysis, preoperative iPTH (OR = 1.111, P = 0.029) and ALP (OR = 1.010, P < 0.001) were the independent risk factors for postoperative HBS. ROC curve analysis suggested that the area under the curve (AUC) values of these two indicators were 0.873 and 0.926, respectively (P < 0.0001). Subsequently, the nomogram model for predicting HBS was constructed. The model verification results indicated that the predicted values were basically consistent with the measured values, with the C-index of 0.943 (95% CI 0.892–0.994). Besides, the calibration curve was consistent with the ideal curve, demonstrating the favorable accuracy and discrimination of the model. Conclusions: Preoperative iPTH and preoperative ALP are the risk factors for postoperative HBS, which can be used to guide the early clinical intervention. [ABSTRACT FROM AUTHOR]

Background: Elabela, a recently discovered hormonal peptide containing 32 amino acids, is a ligand for the apelin receptor. It can lower blood pressure and attenuate renal fibrosis. However, the clinicopathological relationship between Elabela level and renal damage caused by benign hypertension (BHT) and malignant hypertension (MHT) has not been elucidated. Therefore, we investigated the clinicopathological correlation between serum Elabela level and renal damage caused by BHT and MHT. Methods: The participants comprised 50 patients and 25 age-matched healthy adults. The 50 patients were separated into two groups: MHT (n = 25) and BHT groups (n = 25). We analyzed their medical histories, demographics, and clinical examinations, including physical and laboratory tests. Results: The results showed that serum Elabela level decreased gradually with a continuous increase in blood pressure from the healthy control group, BHT, to MHT. Moreover, Elabela levels negatively correlated with BMI (R = − 0.27, P = 0.02), SBP (r = − 0.64, P < 0.01), DBP (r = − 0.58, P < 0.01), uric acid (r = − 0.39, P < 0.01), bun (r = − 0.53, P < 0.01), and Scr (r = − 0.53 P < 0.01) but positively correlated with eGFR (r = 0.54, P < 0.01). Stepwise multivariate linear regression analysis showed that SBP was the variable most related to Elabela (t = − 5.592, P < 0.01). Conclusions: Serum Elabela levels decreased in patients with hypertension, especially malignant hypertension, and has the potential to be a marker of hypertension-related kidney damage. [ABSTRACT FROM AUTHOR]

IgA nephropathy (IgAN) is the most common primary glomerular disease in the world, and up to 40% of patients with IgAN develop end-stage renal disease (ESRD). At present, an increasing amount of evidence indicates that the pathogenesis of IgAN is related to autoimmunity. In recent years, several studies have shown that B cell activating factors (BAFF), also known as B lymphocyte stimulators (BLyS), and proliferation-inducing ligand APRIL are extremely important for the activation of autoimmune signalling pathways, which have become key targets for the treatment of IgAN. As a dual-target biological agent, telitacicept can inhibit both BLyS and APRIL cytokines, improve the function of renal immune complexes, and reduce haematuria and proteinuria, which play important roles in IgAN pathogenesis and long-term prognosis. This article reviews the role of telitacicept in IgA nephropathy and discusses its potential for use in the treatment of IgAN and other autoimmune diseases where pathogenesis is driven by B cells. [ABSTRACT FROM AUTHOR]

Supercritical CO2 (scCO2) extrusion foamed high-melt-strength (HMS) polypropylene (PP) often suffers from low cell density, large cell sizes, and poor cell structure uniformity due to the poor nucleation rates of CO2 in the PP. To remedy this, various inorganic fillers have been used as heterogeneous nucleation agents. Although their efficient nucleation effects have been demonstrated, the preparation of these fillers causes some adverse effects on the environment/human health or involves relatively expensive processes or non-eco-friendly chemicals. In this work, biomass-based lignin is studied as a sustainable, lightweight, and cost-effective nucleating agent. It is found that scCO2 could assist in situ dispersion of lignin in the PP in the foaming process, leading to significantly increased cell density, smaller cells, and improved cell uniformity. The Expansion Ratio is also simultaneously improved due to reduced diffusive gas loss. The PP/lignin foams with low lignin loadings exhibit higher compression moduli and plateau strengths than the PP foams with the same densities owing to the improved cell uniformity and probably also the reinforcing effect of the small lignin particles in cell walls. Moreover, the energy absorption capability of the PP/lignin foam with 1 wt% lignin could match the PP foam with similar compression plateau strengths; even the density of the former is 28% lower than the latter. Therefore, this work provides a promising approach to a cleaner and more sustainable production of HMS PP foams. [ABSTRACT FROM AUTHOR]

Psoriasis is a systemic inflammatory disease that is associated with increased risk of several diseases, such as psoriatic arthritis (PsA), inflammatory bowel disease, and cardiovascular diseases. About 20 to 30% patients with psoriasis subsequently develop PsA. IgA nephropathy is the most common primary glomerular disease world-wide. Psoriasis and IgA nephropathy appear to be associated, but the mechanism underlying this connection is unclear. Tofacitinib and leflunomide are common treatments for psoriatic arthritis. We administered tofacitinib combined with leflunomide to a 38-year-old female patient who presented with PsA and IgA nephropathy. After treatment, she experienced significant reductions in the psoriatic lesions, pain in the right knee joint, and proteinuria. Administration of tofacitinib combined with leflunomide for treatment of a patient who had PsA complicated with IgA nephropathy led to significant resolution of the symptoms of both conditions. These results suggest similarities in the pathogenesis of PsA and IgA nephropathy and a possible new treatment for IgA nephropathy. [ABSTRACT FROM AUTHOR]

Lupus nephritis (LN) is a significant cause of various acute and chronic renal diseases, which can eventually lead to end-stage renal disease. The pathogenic mechanisms of LN are characterized by abnormal activation of the immune responses, increased cytokine production, and dysregulation of inflammatory signaling pathways. LN treatment is an important issue in the prevention and treatment of systemic lupus erythematosus. Mesenchymal stem cells (MSCs) have the advantages of immunomodulation, anti-inflammation, and anti-proliferation. These unique properties make MSCs a strong candidate for cell therapy of autoimmune diseases. MSCs can suppress the proliferation of innate and adaptive immune cells, such as natural killer cells (NKs), dendritic cells (DCs), T cells, and B cells. Furthermore, MSCs suppress the functions of various immune cells, such as the cytotoxicity of T cells and NKs, maturation and antibody secretion of B cells, maturation and antigen presentation of DCs, and inhibition of cytokine secretion, such as interleukins (ILs), tumor necrosis factor (TNF), and interferons (IFNs) by a variety of immune cells. MSCs can exert immunomodulatory effects in LN through these immune functions to suppress autoimmunity, improve renal pathology, and restore kidney function in lupus mice and LN patients. Herein, we review the role of immune cells and cytokines in the pathogenesis of LN and the mechanisms involved, as well as the progress of research on the immunomodulatory role of MSCs in LN. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the clinical and pathological characteristics of lupus nephritis (LN) patients with serositis and analyse the relationship between serositis and hyperuricemia (HUA) in LN patients in northeast China. Methods: The data of patients with LN diagnosed by renal biopsy in our hospital from April 2013 to May 2020 were retrospectively analyzed. The differences between the non-serositis and serositis groups were compared by t tests and Chi-square test. Factors with P < 0.05 in the univariate analyses were investigated further using binary logistic regression analysis to investigate the independent risk factors of serositis in patients with LN. Results: LN patients with serositis were more likely to have fever, hypertension, neuropsychiatric and hematological involvement than those without serositis (P < 0.05). Compared with the non-serositis group, LN patients with serositis were prone to have HUA, high D-dimer, high triglycerides, and had significant differences in the levels of plasma albumin (Alb), estimated glomerular filtration rate (eGFR), erythrocyte sedimentation rate, C-reactive protein, complement C3, 24-h urinary protein, pathological types, pathological score and SLEDAI score. Logistic regression analysis showed that HUA was one of risk factors for serositis in LN patients. The rate of complete remission in LN patients with serositis was significantly lower (P < 0.05) and the rate of no remission and mortality were significantly higher (P < 0.05) than LN patients without serositis. Conclusion: LN patients with serositis had more severe clinical and pathological manifestations, higher systemic lupus erythematosus (SLE) activity and worse prognosis. Hyperuricemia is associated with serositis in LN patients. [ABSTRACT FROM AUTHOR]

Bio‐based and biodegradable polymer composites, most notably poly(l‐lactic acid) (PLLA) and poly(3‐hydroxybutyrate) (PHB), represent a promising solution to replace conventional petroleum‐based plastics. However, the brittleness and low miscibility of PLLA and PHB remain two major obstacles to practical applications. In this work, first PLLA/PHB blends are reported by melt mixing with a rigid component, poly(methyl methacrylate) (PMMA). Driven by favorable entropy, PMMA forms an interfacial nanolayer, which transforms the morphology of resultant blends. The ternary blends show 55‐fold increase in elongation, 50‐fold in toughness, and metal‐like malleability (≈180° bending and twisting), while retaining its high stiffness (3.4 GPa) and strength (≈50 MPa). The mechanical improvement arises from numerous craze fibrils and shear deformation of the matrix, induced by the incorporated PMMA. Furthermore, this generic strategy can be applied to design other mechanically robust biocomposites for advanced green devices. [ABSTRACT FROM AUTHOR]

The development of earth‐abundant oxygen reduction reaction (ORR) catalysts with high catalytic activity and good stability for practical metal‐air batteries remains an enormous challenge. Herein, a highly efficient and durable ORR catalyst is reported, which consists of atomically dispersed Co single atoms (Co‐SAs) in the form of Co‐N4 moieties and small Co nanoparticles (Co‐SNPs) co‐anchored on nitrogen‐doped porous carbon nanocage (Co‐SAs/SNPs@NC). Benefiting from the synergistic effect of Co‐SAs and Co‐SNPs as well as the enhanced anticorrosion capability of the carbon matrix brought by its improved graphitization degree, the resultant Co‐SAs/SNPs@NC catalyst exhibits outstanding ORR activity and remarkable stability in alkaline media, outperforming Co‐SAs‐based catalyst (Co‐SAs@NC), and benchmark Pt/C catalyst. Density functional theory calculations reveal that the strong interaction between Co‐SNPs and Co‐N4 sites can increase the valence state of the active Co atoms in Co‐SAs/SNPs@NC and moderate the adsorption free energy of ORR intermediates, thus facilitating the reduction of O2. Moreover, the practical zinc‐air battery assembled with Co‐SAs/SNPs@NC catalyst demonstrates a maximum power density of 223.5 mW cm–2, a high specific capacity of 742 W h kg–1 at 50 mA cm–2 and a superior cycling stability. [ABSTRACT FROM AUTHOR]

Elabela, also known as Toddler or Apela, is a recently discovered hormonal peptide containing 32 amino acids. Elabela is a ligand of the apelin receptor (APJ). APJ is a G protein-coupled receptor widely expressed throughout body, and together with its cognate ligand, apelin, it plays an important role in various physiological processes including cardiovascular functions, angiogenesis and fluid homeostasis. Elabela also participates in embryonic development and pathophysiological processes in adulthood. Elabela is highly expressed in undifferentiated embryonic stem cells and regulates endoderm differentiation and cardiovascular system development. During differentiation, Elabela is highly expressed in pluripotent stem cells and in adult renal collecting ducts and loops, where it functions to maintain water and sodium homeostasis. Other studies have also shown that Elabela plays a crucial role in the pathogenesis of kidney diseases. This review addresses the role of Elabela in kidney diseases including renal ischemia/reperfusion injury, hypertensive nephropathy, diabetic nephropathy, and cardiorenal syndrome. [ABSTRACT FROM AUTHOR]

Aims: Immunoglobulin A nephropathy (IgAN) is the most common primary glomerular disease to cause end‐stage kidney disease. This study investigated the difference in urinary exosomal circular RNA (circRNA) expression profiles between patients with IgAN and healthy controls (HCs), for better understanding of gene regulation in exosomes of IgAN patients. Methods: A pairwise comparison of urinary circRNA expression profiles between IgAN patients and HCs was performed using methods, including high‐throughput sequencing and quantitative polymerase chain reaction. Moreover, the potential functions of differentially expressed circRNAs (DECs) in IgAN were investigated by gene ontology (GO) enrichment analysis; Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis; and the circRNA‐miRNA‐mRNA network. Results: We identified 450 upregulated and 26 downregulated circRNAs in the IgAN patients. GO analysis showed that these enriched circRNAs might regulate primary miRNA processing, the ability of angiotensin receptor binding, and stress fibre function. KEGG analysis suggested these DECs may be closely associated with the phosphoinositide‐3‐kinase‐protein kinase B/Akt (PI3K‐Akt) signalling pathways. Network analysis revealed the relationship between circRNAs and their target genes. Conclusion: The identified DECs may be useful for both researches on molecular aetiology of IgAN and development of potentially novel non‐invasive biomarkers of IgAN. SUMMARY AT A GLANCE: An RNA‐sequence analysis of RNAs in urinary exosomes identified a number of differentially expressed circular RNAs in immunoglobulin A nephropathy (IgAN) patients as compared to healthy controls. These circRNAs are associated with the regulation of pathways relevant to IgAN and may provide useful non‐invasive biomarkers for this condition. [ABSTRACT FROM AUTHOR]

Recently, lithium metal batteries (LMBs) have regained significant attention as a type of promising rechargeable energy storage device with desired high energy density and long lifetime. Nevertheless, the persistent growth of lithium dendrites during the lithium dripping/stripping process could induce severe safety issues and shorten the lifespan of LMBs, limiting their practical application. In this work, we designed a polymeric one-side conductive Janus separator with preferably oriented pores to effectively reduce the local current density of the electrode and thus minimize the active sites for the germination of lithium dendrites, while also simultaneously enhancing the ionic conductivity to stabilize the Li anode. Such Janus separators could be facilely fabricated from polyvinyl alcohol (PVA) and polyaniline (PANI) precursor aqueous solutions via directional freezing and phase inversion. Our characterization results show that the Janus separator exhibits good surface electrical conductivity on its PANI side and much enhanced ion conductivity owing to the preferably oriented pores and high porosity and also displays a good balance of flexibility and stiffness, excellent wrinkle resistance, and high thermal stability. Moreover, it is confirmed that the Janus separator with oriented pores can efficiently retard the growth of lithium dendrites and promote the formation of a uniform and stable solid electrolyte interphase layer. As a result, compared with the reference separators, including a PVA–PANI Janus separator with random pores, the Janus separator with preferably oriented pores provides cells with a stable and long cycling lifespan and a much higher coulombic efficiency. This work provides a promising new approach to safe, stable and high-performance rechargeable LMBs. [ABSTRACT FROM AUTHOR]

The association of serum elabela (ELA) and apelin with the progression of chronic kidney disease (CKD) is unknown. We determined if serum ELA and apelin levels were associated with CKD stage. This observational study involved 60 CKD patients and 20 healthy, age-, race-, and gender-matched controls. The participants were grouped according to renal function as follows: normal control group, CKD1 group (stage-1 CKD, 20 patients), CKD3 group (stage-3 CKD, 20 patients), and CKD5 group (stage-5 CKD, 20 patients) in accordance with the Kidney Disease Outcomes – Quality Initiative criteria. We recorded the demographic, clinical, and biochemical data of all participants. Serum ELA and apelin levels were measured using commercially available enzyme-linked immunosorbent assays. Serum ELA levels gradually and significantly declined with decreases in the estimated glomerular filtration rate (eGFR). Serum ELA showed significant negative correlations with serum creatinine (r = −0.529, p <.001), blood urea nitrogen (r = −0.575, p <.001), systolic blood pressure (r = −0.455, p <.001), and diastolic blood pressure (r = −0.450, p <.001), and significant positive correlations with hemoglobin (r = 0.523, p <.001) and eGFR (r = 0.728, p <.001). Multiple regression analysis showed that eGFR independently influenced serum ELA levels. No significant association was found between serum apelin levels and CKD progression. In CKD patients, serum ELA levels decreased with decreasing eGFR. This finding may provide a new target for the prediction, diagnosis, and staging of CKD. [ABSTRACT FROM AUTHOR]

Context:In vitro and in vivo research has shown that curcumin can alleviate diabetes and the relevant complications. Objective: To investigate the effect of curcumin on gestational diabetes (GD). Materials and methods: C57 BL/KsJdb/+(db/+) mice and C57 BL/KsJ+/+ mice (10–12 weeks old) were divided into four groups (n = 15): normal pregnancy (C57 BL/KsJ+/+), GD (C57 BL/KsJdb/+), GD plus low dose curcumin (50 mg/kg, orally gavage every day) and GD plus high dose curcumin (100 mg/kg, orally gavage every day). The tolerance of glucose and insulin were measured on gestation day 10. Body weight at birth and litter size of offspring were investigated, and the expression of oxidative stress factors [thiobarbituric acid reactive substance (TBARS), glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT)] and AMP-activated protein kinase (AMPK), phospho-AMPK, histone deacetylases 4 (HDAC4), pHDAC4 and glucose-6-phosphatase (G6Pase) in the livers were analyzed by ELISA and Western blot on gestation day 20. Results: High dose curcumin could partly ameliorate the intolerance of glucose and insulin, and completely restore the litter size and the body weight of GD mice through decreased TBARS expression (p < 0.05) and increased GSH, SOD and CAT expression (p < 0.05). Enhanced AMPK activation, accompanied with decreased HDAC4 and G6Pase expression (p < 0.05) were partly contributed to the alleviation of GD mediated by curcumin. Conclusions: Although further detailed mechanism needs to be deciphered, curcumin can be considered as an alternative treatment for gestational diabetes. [ABSTRACT FROM AUTHOR]

Human placenta-derived mesenchymal stem cells (pMSCs) are considered a good source for cell therapy. The purpose of this study was to observe whether the transplantation of human pMSCs would affect the treatment of lupus nephritis (LN)-prone MRL/lpr mice. Multiple injections (at the 16th, 18th, and 20th week of age) of 1 × 106 pMSCs were administered. Urine was collected to evaluate proteinuria and urine creatinine levels. Blood was collected for the measurement of serum antinuclear antibody (ANA) and anti-double-stranded DNA (dsDNA) antibody levels. Renal tissues were collected for histological staining and examination by light and electron microscopy quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western Blot. The results confirmed that pMSC treatment reduced the severity of 24-h proteinuria, decreased the production of anti-dsDNA antibodies, and ameliorated renal pathological changes in MRL/lpr mice. Furthermore, pMSCs reduced renal inflammation by inhibiting the expression of nuclear factor kappa B (NF-κB) and then downregulating the expression of tumor necrosis factor-α (TNF-α), intercellular cell adhesion molecule-1 (ICAM-1), and plasminogen activator inhibitor-1 (PAI-1). Therefore, our present study demonstrated a protective effect of pMSCs against renal injury and inflammation in MRL/lpr mice. [ABSTRACT FROM AUTHOR]

Carbon nanostructures containing binary transition metal compounds have shown great potential for applications such as electrocatalysis. In this article, we report a one-pot synthesis of Co(ii)–Fe(iii)–polydopamine (PDA) complex nanospheres as a facile approach to binary metal-doped carbon nanostructures. The complex nanospheres were prepared simply by polymerization of dopamine (DOPA) in a basic aqueous solution containing both types of transition metal ion. Results show that cobalt(ii) ions do not form complexes with DOPA, whereas can form coordination bonds with PDA oligomers after the initiation of polymerization, leading to irregular shaped complex particles. When both cobalt(ii) and Fe(iii) ions are present in the polymerization system, Fe(iii) ions, which are able to form complexes with DOPA before the initiation of polymerization, play a dominant role in determining the morphology of the complex nanostructure, leading to hybrid complex nanospheres. Furthermore, the Co(ii)–Fe(iii)–PDA complex nanospheres can be easily converted to mesoporous N-doped carbon nanospheres with embedded CoFe2O4/CoFe nanoparticles. Electrochemical studies suggest that these nanospheres exhibit enhanced bifunctional electrocatalytic performance over commercial Pt/C towards ORR and OER. They also show good stability with steady cycling performance for over 300 cycles when used as a bifunctional oxygen electrocatalyst in a rechargeable zinc–air battery cell. [ABSTRACT FROM AUTHOR]

Lightweight flexible carbon nanotube (CNT)/polyaniline (PANI) free standing films having the highest reported specific shielding effectiveness (SSE) of 7.5 × 104 dB cm2 g−1 were developed using amine-functionalized CNTs, which could be attributed to the high conductivity (3009 S cm−1) and low density of the amine-functionalized CNT/PANI composites. The mechanism behind the high conductivity is also studied. [ABSTRACT FROM AUTHOR]

In this article, we report, for the first time, the preparation of polyaniline/manganese dioxide (PANI/MnO2) hybrid electrochromic films via one-pot potentiostatically anodic electrodeposition from an aqueous solution containing aniline and manganese sulfate. In the one-pot deposition process, electropolymerization of aniline and electrodeposition of MnO2 occur simultaneously, while some of the resultant MnO2 can act as an oxidizer to further initiate chemical polymerization of aniline, facilitating rapid growth of the hybrid films. This unique deposition mechanism gives rise to significant differences between the hybrid and neat PANI films in morphology, structures, electrochemical and electrochromic properties. Compared with neat PANI films, the hybrid film with optimal MnO2 content shows much higher optical contrast, coloration efficiency, and cycling stability. The excellent performance of the hybrid film can be attributed to its unique porous morphology with interconnected small nanoparticles, and donor–acceptor interactions between PANI and MnO2. [ABSTRACT FROM AUTHOR]

Chemically cross-linked Si xO y cage clusters embedded in N-doped carbon were prepared by thermal treatment of octaammonium polyhedral oligomeric silsesquioxane (POSS; (SiO1.5C3H6NH3Cl)8) in an inert environment. Transmission electron microscopic studies show that by annealing at 900 °C, Si-rich clusters with a size of approximately 5 nm were formed and uniformly distributed in a lighter matrix. XPS analysis indicates that the sample obtained from annealing at 900 °C (P900) has a chemical composition of Si6.5O12.0C9.3N0.5 and it also contains substantial amounts of Si−C and C−O bonds, sp2 C, and a small number of C=N bonds, in addition to Si−O bonds. Together with thermogravimetric analysis, this suggests that the clusters are likely to be formed by chemical cross-linking several POSS cages through Si−C or C−O bonds, whereas the matrix may be N-doped carbon that results from carbonization of some detached side-chains. When used as a lithium-ion battery anode, P900 exhibits stable and high cycling and rate capacity. The capacity can be maintained for at least 1000 cycles. This is much better than results for anodes made from silicon oxides, which could be ascribed to 1) the less compact but fairly stable Si−O active sites brought by the cage structure and the cross-linking; 2) the small size of the clusters that ensures smooth and complete lithium insertion/extraction; and 3) the 'island-sea' morphology for the clusters-in-carbon hybrid that enhances interfacial interactions and facilitates charge conduction. [ABSTRACT FROM AUTHOR]

In order to enhance the electrochromic performance of sol–gel derived WO3 coatings, especially the electrochemical cycling stability, a small amount of dopamine (DA) is introduced into a peroxotungstic acid (PTA) precursor sol to form complexes with tungsten on the surface of PTA colloidal nanoparticles. The DA molecules act as a precursor stabilizer, giving the sol a very long shelf life, which is crucial for practical applications, and also play the role of a structure-directing agent, providing a nanocrystal-embedded amorphous WO3 coating by annealing at 300 °C. Compared with the corresponding neat WO3 coating, the modified WO3 coating prepared from the complex sol gives much higher optical contrast, a faster switching speed and a higher coloration efficiency. It also shows excellent long-term cycling stability (maintaining a stable high contrast up to 35 000 cycles), which is far superior to not only the reference neat WO3 coating but also WO3 coatings prepared via other wet chemical routes. The excellent cycling stability may be attributed to the buffering effect of the nanocrystal-embedded amorphous regions, which accommodate the volume change of the nanocrystals induced by ion insertion/extraction. The uniform distribution of the nanometer-sized amorphous and crystal regions may help to reduce stress concentration and hence suppress erosion caused by local stress. [ABSTRACT FROM AUTHOR]

An aqueous suspension of WO3/poly(4-(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl-methoxy)-1-butanesulfonic acid) (PEDTS) hybrid nanoparticles (NPs) is prepared by air-assisted oxidative polymerization and simultaneous attachment of PEDTS on WO3-NPs, and used for electrochromic (EC) film fabrication via air-brush spraying. The hybrid EC device exhibits enhanced EC properties compared to the ones based on WO3-NP or PEDTS alone. [ABSTRACT FROM AUTHOR]

A series of 4,9-dihydro- s-indaceno[1,2-b:5,6-b′]dithiophene-based conjugated polymers with 3,4-bis(dodecyloxy)thiophene, 3,3-bis((dodecyloxy)methyl)-3,4-dihydro-2 H-thieno[3,4- b] [, ] dioxepine and 3,4-ethylenedioxythiophene as co-monomers were synthesized via Stille coupling reaction in more than 50 % yields. These polymers possess relatively high number-average molecular weights of 14,900-21,000 g mol and exhibit good solubility in common organic solvents. The physical and electrochemical properties of these polymers were studied, and the polymers showed optical bandgap between 2.04 and 2.08 eV. Electrochromic devices showed a rare and reversible colour change between dark red at neutral state and black at oxidized state with optical switching contrast ratios of up to 50 % at λ and 90 % at 1500 nm in the visible and NIR regions, respectively. Graphical abstract: 4,9-dihydro- s-indaceno[1,2-b:5,6-b']dithiophene-based conjugated polymers showing rare and reversible colour change between dark red at neutral state and black at oxidized state were synthesized via Stille coupling. These polymers possess high optical contrast in both the visible and NIR regions.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this article, it is demonstrated that the electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF–HFP)) nanofibrous mat functionalized with (3-aminopropyl)triethoxysilane is a versatile platform for the fabrication of hybrid nanofibrous mats by covalently attaching various types of inorganic oxide nanoparticles on the nanofiber surface via a sol–gel process. In particular, SiO2-on-P(VDF–HFP) nanofibrous mats synthesized using this method is an excellent ionic liquid (IL) host for electrolyte applications. The IL-based electrolytes in the form of free-standing mats are obtained by immersing SiO2-on-P(VDF–HFP) mats in two types of liquid electrolytes, namely LiClO4/1-butyl-3-methylimidazolium tetrafluoroborate and bis(trifluoromethane)sulfonimide lithium salt/1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide. It is found that the surface attached SiO2 nanoparticles can effectively serve as salt dissociation promoters by interacting with the anions of both ILs and lithium salts through Lewis acid–base interactions. They dramatically enhance the ionic conductivity and lithium transference number of the electrolytes. In addition, better compatibility of the electrolytes with lithium electrodes is also observed in the presence of surface-attached SiO2. Using IL-loaded SiO2-on-P(VDF–HFP) nanofibrous mats as the electrolytes, electrochromic devices display higher transmittance contrast, while Li/LiCoO2 batteries show significantly improved C-rate performance and cycling stability. This class of novel non-volatile electrolytes with high ionic conductivity also has the potential to be used in other electrochemical devices. [ABSTRACT FROM AUTHOR]

A series of dithienothiophene-based electrochromic polymers are synthesized by a Stille coupling reaction of 2,6-bis(trimethylstannyl)dithieno[3,2- b:2′,3′- d]thiophene, 2,5-dibromo-3,4-bis(dodecyloxy)thiophene, and tris(4-bromophenylamine). The resulting polymers have high molecular weights in the range of 59 200 to 81 300 g mol−1, and good solubility in common organic solvents. The polymer films are purple/red in neutral states and gradually become gray when oxidized to an intermediate state and blue when fully oxidized. Incorporation of triphenylamine into the polymer chains has resulted in a significant increase in the redox stability, which renders this a potential method to create high-performance electrochromic polymers. [ABSTRACT FROM AUTHOR]

Poly(lactide) (PLA)–lignin composites were fabricated by blending lignin-g-rubber-g-poly(d-lactide) copolymer particles and commercial poly(l-lactide) (PLLA) in chloroform. To synthesize the copolymer, a poly(ε-caprolactone-co-lactide) (PCLLA) rubbery layer was formed via the lignin-initiated ring opening copolymerization of an ε-caprolactone/l-lactide mixture, followed by the formation of poly(d-lactide) (PDLA) outer segments via the polymerization of d-lactide. The PDLA segments may contribute to strong interfacial interactions between lignin-rubber-PDLA and PLLA matrix by stereocomplexation, which was observed using differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR) and wide angle X-ray scattering (WAXS). The quasi-random structure of PCLLA and the formation of the outer PDLA segments were characterized by nuclear magnetic resonance (NMR). A Tg of ∼−36 °C for PCLLA was detected by DSC, which confirms the rubbery character of the synthesized copolymer. The resulting renewable and biodegradable composites exhibited a six-fold increase of elongation at break and a simultaneous improvement in their tensile strength and Young's modulus, though to a lesser extent. Light scattering, WAXS, small angle X-ray scattering (SAXS) and scanning electron microscope (SEM) studies suggested that good lignin dispersion, rubber-initiated crazing and strong filler/matrix interactions due to stereocomplexation are the effective mechanisms behind the excellent mechanical performance of these composites. [ABSTRACT FROM AUTHOR]

An electrofluorochromic (EFC) conjugated copolymer ( PEFC) containing carbazole and benzothiadiazole (BTD) moieties is synthesized through Suzuki coupling followed by electrochemical polymerization, resulting in a nanoporous EFC polymer electrode. The electrode exhibits high sensitivity and selectivity in the EFC detection of cyanide anions (CN−) in largely aqueous electrolyte (67 vol % water) because electrochemical oxidation of PEFC leads to significant fluorescence quenching, and the presence of different concentrations (1 to 100 μ M) of CN− in the electrolyte can weaken the oxidative quenching to substantially different extents. Although PEFC is hydrophobic in the neutral state, it is converted to radical cation/dication states upon oxidation, rendering the PEFC some hydrophilicity. Moreover, its nanoporous morphology provides a large surface area and short diffusion distance, facilitating the movement of CN− in the electrolyte into the PEFC film to interact with receptors. Density functional theory calculations show that the noncovalent interaction between electron-deficient BTD and nucleophilic CN− is energy favorable in the oxidized states in both aqueous and organic media, suggesting that the specific π−-π+ interaction plays the main role in the CN− detection. [ABSTRACT FROM AUTHOR]

In this work, unique carbonaceous nanocups, densely attached on a free-standing hollow microfibrous mat, were prepared via a mussel-inspired biomimetic polydopamine (PDA)-coating process using electrospun porous microfibers as the templates, followed by annealing. Electron microscopic studies show that the diameters and depths of the ellipsoid-shaped nanocups are in the range of a few hundred nanometers, and they have small openings of less than 100 nm, allowing the cups to act as nano-chambers to host other functional materials as well as nano-reactors for the synthesis of embedded nanostructures. To demonstrate the functions of such a unique hollow structure, the nanocups were used to host a MoS2 precursor, and through hydrothermal treatment, MoS2 nanosheets were effectively trapped in the nanocups. The MoS2-in-nanocups were used as an anode in lithium ion batteries. Good cyclability and excellent rate capacity (around 520 mA h g-1 at 2 A g-1) were achieved owing to the efficient charge transport provided by the good contact of the MoS2 nanosheets with the conductive nanocups and surrounding electrolyte. The nanocups could also act as buffering chambers to effectively accommodate the volume expansion of MoS2 during cycling. [ABSTRACT FROM AUTHOR]

Inspired by the high transition-metal-ion content in mussel glues, and the cross-linking and mechanical reinforcement effects of some transition-metal ions in mussel threads, high concentrations of nickel(II), cobalt(II), and manganese(II) ions have been purposely introduced into the reaction system for dopamine polymerization. Kinetics studies were conducted for the Ni2+-dopamine system to investigate the polymerization mechanism. The results show that the Ni2+ ions could accelerate the assembly of dopamine oligomers in the polymerization process. Spectroscopic and electron microscopic studies reveal that the Ni2+ ions are chelated with polydopamine (PDA) units, forming homogeneous Ni2+-PDA complexes. This facile one-pot approach is utilized to construct transition-metal-ion-PDA complex thin coatings on graphene oxide, which can be carbonized to produce robust hybrid nanosheets with well-dispersed metallic nickel/metallic cobalt/manganese(II) oxide nanoparticles embedded in PDA-derived thin graphitic carbon layers. The nickel-graphene hybrid prepared by using this approach shows good catalytic properties and recyclability for the reduction of p -nitrophenol. [ABSTRACT FROM AUTHOR]

Titanium surface was modified by anodization in phosphoric acid solution at the voltages of 100 and 250 V, respectively. Surface characteristics and corrosion behaviors of anodized titanium were investigated before and after hydrothermal exposure in 3.5 wt.% NaCl solution at 160 °C for 24 h. It was found that anodization at 100 and 250 V resulted in the formation of a dense and a porous TiO2 layer, respectively. The existence of anatase in the oxide layers of the 250-V samples was confirmed by X-ray diffraction analysis but not in the oxide layers of the 100-V samples. After the hydrothermal exposure, the surface morphology of the 100-V sample changed significantly, and discrete nanorods were formed on the surface. In contrast, the 250-V sample basically preserved their original surface structures after the exposure except that numerous closely packed nanoparticles emerged on the surface. X-ray diffraction analysis indicated that the exposure transformed the amorphous oxides into crystalline anatase. The corrosion behavior investigation of anodized titanium showed that the hydrothermal exposure had slight influence on the corrosion resistance of the 100-V samples but decreased the corrosion resistance of the 250-V samples significantly. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hybrid thin films composed of multilayer poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonic acid) (PEDOT:PSS) and tungsten trioxide (WO3) were electrochemically deposited on indium tin oxide (ITO) from a one-pot solution using a square-wave galvanostatic method. The morphology of the hybrid thin films could be easily manipulated to optimize their electrochromic properties by adjusting deposition conditions. In the hybrids, both components can be simultaneously switched to coloured or bleached states. The hybrid film obtained with very short deposition times of PEDOT:PSS and WO3 in each cycle exhibits significantly enhanced electrochromic properties. The optical contrast of the hybrid film is higher than that of PEDOT:PSS or WO3 films of the same thickness. Moreover, the stability of the hybrid film is also drastically enhanced. The enhancement may be attributed to the favourable interactions between the two components, i.e., PEDOT:PSS may enter the defect sites in electrodeposited WO3, preventing surface-defect-induced anodic dissolution during cycling, while the surface functional groups of WO3 may act as dopants to inhibit over-oxidation of PEDOT, as well as the large interfacial area created using this unique one-pot multilayer deposition method. [ABSTRACT FROM AUTHOR]

Coatings have been applied widely in aerospace, biomedical, electronic, and many other industries. The performance of a coating is dictated by the adhesion between the coating and the underlying substrate. Thus, the evaluation of coating adhesion is critical for the assessment of the quality of a coating and its fitness for service. However, this evaluation is not straightforward, and various mechanical and non-mechanical evaluation methods have been developed. This paper presents a comprehensive review of the currently most widely employed mechanical methods. The interface fracture mechanics that provides the fundamental knowledge for conducting adhesion assessment and analysis is briefly introduced. Detailed discussions are presented on various sandwich specimen-based and bimaterial specimen-based testing methods, with emphasis on the principles, merits, limitations, typical applications, and recent improvements of each method. [ABSTRACT FROM AUTHOR]