Universal, minute-scale synthesis of transition metal compound nanocatalysts via graphene-microwave system for enhancing sulfur kinetics in lithium-sulfur batteries.

The application of Li-S batteries on large scale is held back by the sluggish sulfur kinetics and low synthesis efficiency of sulfur host. In addition, the preparation of catalysts that promote polysulfide redox kinetics is complex and time-consuming, reducing the cost of raw materials in Li-S. Here, a universal synthetic strategy for rapid fabrication of sulfur cathode and metal compounds nanocatalysts is reported based on microwave heating of graphene. Heat-sensitive materials can achieve rapid heating due to graphene reaching 500 ℃ within 4 s via microwave irradiation. The MoP-MoS2/rGO catalyst demonstrated in this work was synthesized within 60 s. When used for catalysts for Li-S batteries whose graphene/sulfur cathodes were also synthesized by microwave heating, enhanced catalytic effect for sulfur redox reaction was verified via experimental and DFT theoretical results. Benefiting from fast redox reaction (MoP), smooth Li+ diffusion pathways (MoS2), and large conductive network (rGO), the assembled Li-S battery with MoP-MoS2/rGO-Add@CS displays a remarkable initial specific capacity, stable lithium anode and good cycle stability (in pouch cells) using this two-pronged strategy. The work provides a practical strategy for advanced Li-S batteries toward a wide range of applications.

Exogenous Electroactive Microbes Regulate Soil Geochemical Properties and Microbial Communities by Enhancing the Reduction and Transformation of Fe(III) Minerals.

Electroactive microbes can conduct extracellular electron transfer and have the potential to be applied as a bioresource to regulate soil geochemical properties and microbial communities. In this study, we incubated Fe-limited and Fe-enriched farmland soil together with electroactive microbes for 30 days; both soils were incubated with electroactive microbes and a common iron mineral, ferrihydrite. Our results indicated that the exogenous electroactive microbes decreased soil pH, total organic carbon (TOC), and total nitrogen (TN) but increased soil conductivity and promoted Fe(III) reduction. The addition of electroactive microbes also changed the soil microbial community from Firmicutes-dominated to Proteobacteria-dominated. Moreover, the total number of detected microbial species in the soil decreased from over 700 to less than 500. Importantly, the coexistence of N-transforming bacteria, Fe(III)-reducing bacteria and methanogens was also observed with the addition of electroactive microbes in Fe-rich soil, indicating the accelerated interspecies electron transfer of functional microflora.

Porosity Tunable Poly(Lactic Acid)-Based Composite Gel Polymer Electrolyte with High Electrolyte Uptake for Quasi-Solid-State Supercapacitors.

The growing popularity of quasi-solid-state supercapacitors inevitably leads to the unrestricted consumption of commonly used petroleum-derived polymer electrolytes, causing excessive carbon emissions and resulting in global warming. Also, the porosity and liquid electrolyte uptake of existing polymer membranes are insufficient for well-performed supercapacitors under high current and long cycles. To address these issues, poly(lactic acid) (PLA), a widely applied polymers in biodegradable plastics is employed to fabricate a renewable biocomposite membrane with tunable pores with the help of non-solvent phase inversion method, and a small amount of poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) is introduced as a modifier to interconnect with PLA skeleton for stabilizing the porous structure and optimizing the aperture of the membrane. Owing to easy film-forming and tunable non-solvent ratio, the porous membrane possesses high porosity (ca. 71%), liquid electrolyte uptake (366%), and preferable flexibility endowing the GPE with satisfactory electrochemical stability in coin and flexible supercapacitors after long cycles. This work effectively relieves the environmental stress resulted from undegradable polymers and reveals the promising potential and prospects of the environmentally friendly membrane in the application of wearable devices.

Case report: Secondary sclerosing cholangitis induced by lapatinib and vinorelbine in a metastasis breast cancer patient.

Secondary sclerosing cholangitis (SSC) is a rare cholestatic liver disease that may have a severe clinical course. A 61-year-old woman with a history of metastasis breast cancer was admitted to our hospital for the second cycle of chemotherapy with lapatinib and vinorelbine. The patient had no reports of elevated liver function tests (LFTs) in the previous multiple chemotherapies or history of liver disease. However, the admission laboratory results showed severe cholestatic liver injury with the possibility of SSC by magnetic resonance cholangiopancreatography. Although chemotherapy was discontinued and patient was treated with hepatoprotective drugs, the LFTs did not improve and liver biopsy indicated mild injury of intrahepatic bile duct epithelium and hepatocyte. We added ursodeoxycholic acid and prednisolone to protect the liver, and laboratory data showed a response. To prevent the progression, lapatinib and vinorelbine were reintroduced and transient increases in alanine aminotransferase and γ-glutamyl transpeptidase were observed. With no evidence of viral or autoimmune liver disease, SSC induced by lapatinib and vinorelbine was diagnosed. This is the first case report of tyrosine kinase inhibitors and vinorelbine induced SSC and clinicians should be aware of the possibility of it. More case reports about this adverse drug reaction are needed to delineate optimal management.

Weighted Gene Co-expression Network Analysis Identifies CALD1 as a Biomarker Related to M2 Macrophages Infiltration in Stage III and IV Mismatch Repair-Proficient Colorectal Carcinoma.

Immunotherapy has achieved efficacy for advanced colorectal cancer (CRC) patients with a mismatch-repair-deficient (dMMR) subtype. However, little immunotherapy efficacy was observed in patients with the mismatch repair-proficient (pMMR) subtype, and hence, identifying new immune therapeutic targets is imperative for those patients. In this study, transcriptome data of stage III/IV CRC patients were retrieved from the Gene Expression Omnibus database. The CIBERSORT algorithm was used to quantify immune cellular compositions, and the results revealed that M2 macrophage fractions were higher in pMMR patients as compared with those with the dMMR subtype; moreover, pMMR patients with higher M2 macrophage fractions experienced shorter overall survival (OS). Subsequently, weighted gene co-expression network analysis and protein-protein interaction network analysis identified six hub genes related to M2 macrophage infiltrations in pMMR CRC patients: CALD1, COL6A1, COL1A2, TIMP3, DCN, and SPARC. Univariate and multivariate Cox regression analyses then determined CALD1 as the independent prognostic biomarker for OS. CALD1 was upregulated specifically the in CMS4 CRC subtype, and single-sample Gene Set Enrichment Analysis (ssGSEA) revealed that CALD1 was significantly correlated with angiogenesis and TGF-ß signaling gene sets enrichment scores in stage III/IV pMMR CRC samples. The Estimation of STromal and Immune cells in MAlignant Tumor tissues using Expression data (ESTIMATE) algorithm and correlation analysis revealed that CALD1 was significantly associated with multiple immune and stromal components in a tumor microenvironment. In addition, GSEA demonstrated that high expression of CALD1 was significantly correlated with antigen processing and presentation, chemokine signaling, leukocyte transendothelial migration, vascular smooth muscle contraction, cytokine-cytokine receptor interaction, cell adhesion molecules, focal adhesion, MAPK, and TGF-beta signaling pathways. Furthermore, the proliferation, invasion, and migration abilities of cancer cells were suppressed after reducing CALD1 expression in CRC cell lines. Taken together, multiple bioinformatics analyses and cell-level assays demonstrated that CALD1 could serve as a prognostic biomarker and a prospective therapeutic target for stage III/IV pMMR CRCs.

Scalable and fast fabrication of holey multilayer graphene via microwave and its application in supercapacitors.

By virtue of its high specific surface area and low tortuosity for ionic storage and transportation, holey graphene has come to be regarded as a promising material for energy storage devices, such as lithium ion batteries, and supercapacitors. For practical applications, a scalable and green preparation method for holey graphene is required. This work proposes a facile preparation method for holey graphene by simply microwaving pristine graphene in air. Compared with previous scalable methods, this method exhibits much greater efficiency, reducing the preparation time from hours to minutes. The mechanism underlying the microwave irradiation-induced formation of nanosized holes involves the interaction between microwaves, electrons, oxygen in air, and carbon atoms in the defect areas of the graphene. The size, density, and distribution of holes can be controlled by tuning the microwave irradiation time and oxygen concentration. Used as a hybrid conductive agent, the as-prepared holey multilayer graphene increases capacitance retention to 96.25% at high current density (8 A g-1), and 96.48% in long cycles (1 A g-1 and 10 000 cycles).

Electron Hopping Enables Rapid Electron Transfer between Quinone-/Hydroquinone-Containing Organic Molecules in Microbial Iron(III) Mineral Reduction.

The mechanism of long-distance electron transfer via redox-active particulate natural organic matter (NOM) is still unclear, especially considering its aggregated nature and the resulting low diffusivity of its quinone- and hydroquinone-containing molecules. Here we conducted microbial iron(III) mineral reduction experiments in which anthraquinone-2,6-disulfonate (AQDS, a widely used analogue for quinone- and hydroquinone-containing molecules in NOM) was immobilized in agar to achieve a spatial separation between the iron-reducing bacteria and ferrihydrite mineral. Immobilizing AQDS in agar also limited its diffusion, which resembled electron-transfer behavior of quinone- and hydroquinone-containing molecules in particulate NOM. We found that, although the diffusion coefficient of the immobilized AQDS/AH2QDS was 10 times lower in agar than in water, the iron(III) mineral reduction rate (1.60 ± 0.28 mmol L-1 Fe(II) d-1) was still comparable in both media, indicating the existence of another mechanism that accelerated the electron transfer under low diffusive conditions. We found the correlation between the heterogeneous electron-transfer rate constant (10-3 cm s-1) and the diffusion coefficient (10-7 cm2 s-1) fitting well with the "diffusion-electron hopping" model, suggesting that electron transfer via the immobilized AQDS/AH2QDS couple was accomplished through a combination of diffusion and electron hopping. Electron hopping increased the diffusion concentration gradient up to 106-fold, which largely promoted the overall electron-transfer rate during microbial iron(III) mineral reduction. Our results are helpful to explain the electron-transfer mechanisms in particulate NOM.

Prognostic value of tumor-infiltrating lymphocyte subtypes in residual tumors of patients with triple-negative breast cancer after neoadjuvant chemotherapy.

BACKGROUND: After neoadjuvant chemotherapy (NAC), non-pathological complete response of breast cancer patients can benefit from tailored adjuvant chemotherapy. However, it is difficult to select patients with poorer prognosis for additional adjuvant chemotherapy to maximize the benefits. Our study aimed to explore whether the subtypes of tumor-infiltrating lymphocytes (TILs) in residual tumors (RT) is related to the prognosis of triple-negative breast cancer (TNBC) after NAC. METHODS: Data from patients with primary TNBC consecutively diagnosed at the Breast Disease Center of Peking University First Hospital from 2008 to 2014 were retrieved, and the cases with RT in the breast after NAC were enrolled. TILs subtypes in RT were observed by double-staining immunohistochemistry, and counted with the median TILs value per square millimeter as the cut-off to define high versus low TILs density in each subtype. The relationships between the TIL density of each subgroup and the clinicopathological characteristics of the RT after NAC patients were analyzed by Fisher exact test. Disease-free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method and log-rank statistics. RESULTS: A total of 37 eligible patients were included in this study, and the median follow-up period was 50 months (range 17-106 months). There was no significant correlation between the infiltrate density of CD4, CD8, CD20, and CD68 lymphocytes and clinic-pathological characteristics. Significantly better prognosis was observed in patients with high CD4-TILs (DFS: P = 0.005, OS: P = 0.021) and high CD8-TILs (DFS: P = 0.018) and low CD20-TILs (OS: P = 0.042). Further analysis showed that patients with CD4/CD20 ratio greater than 1 (DFS: P = 0.001, OS: P = 0.002) or CD8/CD20 ratio greater than 1 (DFS: P = 0.009, OS: P = 0.022) had a better prognosis. CONCLUSIONS: Subtypes of TILs in RT is a potential predictive biomarker of survival in TNBC patients after NAC.

AQDS and Redox-Active NOM Enables Microbial Fe(III)-Mineral Reduction at cm-Scales.

Redox-active organic molecules such as anthraquinone-2,6-disulfonate (AQDS) and natural organic matter (NOM) can act as electron shuttles thus facilitating electron transfer from Fe(III)-reducing bacteria (FeRB) to terminal electron acceptors such as Fe(III) minerals. In this research, we examined the length scale over which this electron shuttling can occur. We present results from agar-solidified experimental incubations, containing either AQDS or NOM, where FeRB were physically separated from ferrihydrite or goethite by 2 cm. Iron speciation and concentration measurements coupled to a diffusion-reaction model highlighted clearly Fe(III) reduction in the presence of electron shuttles, independent of the type of FeRB. Based on our fitted model, the rate of ferrihydrite reduction increased from 0.07 to 0.19 µmol d-1 with a 10-fold increase in the AQDS concentration, highlighting a dependence of the reduction rate on the electron-shuttle concentration. To capture the kinetics of Fe(II) production, the effective AQDS diffusion coefficient had to be increased by a factor of 9.4. Thus, we postulate that the 2 cm electron transfer was enabled by a combination of AQDS molecular diffusion and an electron hopping contribution from reduced to oxidized AQDS molecules. Our results demonstrate that AQDS and NOM can drive microbial Fe(III) reduction across 2 cm distances and shed light on the electron transfer process in natural anoxic environments.

Novel Polyimide Separator Prepared with Two Porogens for Safe Lithium-Ion Batteries.

A porous polyimide (PI) membrane is successfully prepared via nonsolvent-induced phase separation with two porogens: dibutyl phthalate and glycerin. The as-prepared uniform porous PI membrane shows excellent separator properties for lithium-ion batteries (LIBs). Compared with the commercial polyethylene (PE) separator, the PI separator exhibits significant thermal stability, better ionic conductivity, and wettability both in carbonate and ether electrolytes for LIBs. The battery coin-cells assembled with the PI separator is more robust and still works even after heating at 140 °C for 1 h, while the cells with the commercial PE separator could not charge any more due to the shrinkage of the PE under the same condition.

Effects of polyphosphates and orthophosphate on the dissolution and transformation of ZnO nanoparticles.

The fate and toxicity of zinc oxide nanoparticles (ZnO NPs) in nature are affected by solution chemistry such as pH, anions, and natural organic matter (NOM). Inorganic polyphosphates are environmentally ubiquitous phosphorus (P) species that may change the speciation and environmental fate of ZnO NPs. In this study, the interactions of polyphosphates with ZnO NPs and the impacts on ZnO NP dissolution and transformation were investigated and compared with orthophosphate (P1). The results revealed that pyrophosphate (P2), tripolyphosphate (P3), and hexametaphosphate (P6) enhanced whereas P1 inhibited the dissolution of ZnO NPs. In addition, P1, P2, and P3 promoted the transformation of ZnO NPs into zinc phosphate (Zn-P) precipitates via interactions with dissolved Zn2+. However, P6-promoted ZnO NP dissolution was through the formation of soluble Zn-P complexes due to the strong capability of P6 to chelate with Zn2+. The transformation of ZnO NPs in the presence of P3 was affected by reaction time, pH, and P/Zn molar ratio. P3 first formed inner-sphere surface complexes on ZnO NPs, which gradually transformed into crystalline Zn2HP3O10(H2O)6 precipitates. This study provided a new perspective for understanding the reactivity of various forms of inorganic phosphate species with ZnO NPs in the natural environment.