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1.
Sci Total Environ ; 722: 137657, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32199356

RESUMO

The treatment of sewage with high-nitrogen/-phosphorus and low-carbon remains a challenge. A novel iron-carbon galvanic cells strengthened anaerobic/anoxic/oxic process (Fe/C-A2O) was developed for high-nitrogen/-phosphorus and low-carbon sewage treatment. The cost-effective iron-scraps (ISs) was recycled as Fe(0)-source under the mediation of Fe/C galvanic cell reaction to develop effective Fe(0)-oxidizing autotrophic-denitrification and -dephosphorization. Utilizing practical high-nitrogen/-phosphorus and low-carbon sewage as target wastewater, the performance, impact factors, contribution of Fe/C galvanic cell reactions, microbial characteristics, strengthening mechanisms, and application potential of Fe/C-A2O process were investigated. The Fe/C-A2O process achieved high TN and TP removal efficiencies of 92.0 ± 1.3% and 97.2 ± 0.9% with removal loads of 0.176 ± 0.002 kg TN/(m3·d) and 0.017 ± 0.002 kg TP/(m3·d), respectively. Optimal HRT of 12 h, DO of 4.0-4.5 mg/L, and reflux-ratio of 4:1 were obtained, and no sludge-reflux was required. Autotrophic-denitrification and -dephosphorization supported by the Fe/C galvanic cell reactions contributed 63.1% and 75.3% of TN and TP removal, respectively. Microbial characterization revealed the dominance of autotrophic denitrifiers (e.g., Thiobacillus), AOB (e.g., Nitrosomonas), NOB (e.g., Nitrospira), and heterotrophic denitrifiers (e.g., Zoogloea). The mechanism analysis demonstrated that Fe/C galvanic cells strengthened nitrogen removal by raising Fe2+/H2-supported autotrophic denitrification; and strengthened dephosphorization by introducing Fe3+-based PO43--precipitation and enhancing the denitrifying phosphate-accumulation by denitrifying phosphate-accumulating organisms (DPAOs). Based on the efficiency and cost evaluation, the ISs-based Fe/C-A2O process showed significant application potential as an upgrade strategy for traditional A2O process in advanced high-nitrogen/phosphorus and low-carbon sewage treatment.

2.
BMC Ophthalmol ; 20(1): 92, 2020 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-32143590

RESUMO

BACKGROUND: Retinoblastoma (RB) is the most frequent pediatric retinal tumor. In the present study, to elucidate chemoresistance mechanisms and identify potential biomarkers in RB, we utilized RNA sequencing (RNAseq) technological platforms to reveal transcriptome profiles and identify any differentially expressed genes (DEGs) between an etoposide drug-resistant subline (Y79/EDR) and parental Y79 cells. METHODS: To test whether Y79/EDR cells showed resistance to antineoplastic agents for RB, we treated the cells with etoposide, carboplatin and vincristine and analyzed them with a Cell Counting Kit-8 (CCK-8). Y79/EDR and parental Y79 cells were used for RNAseq and bioinformatics analysis to enable a genome-wide review of DEGs between the two lines using the DESeq R package (1.10.1). Then, DEG enrichment in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways was analyzed with KOBAS software. Next, real-time quantitative reverse transcription polymerase chain reaction (real time QRT-PCR) and cytotoxicity assays were performed to experimentally and functionally validate the identified candidate biomarkers. RESULTS: Y79/EDR cells showed resistance to etoposide, carboplatin and vincristine at different concentrations. In total, 524 transcripts were differentially expressed in Y79/EDR cells based on analysis of fragments per kilobase of transcript per million fragments mapped (FPKM); among these, 57 genes were downregulated and 467 genes were upregulated in Y79/EDR cells compared to parental Y79 cells. We selected candidate DEGs, including ARHGAP9, HIST1H4H, RELN, DDIT4, HK2, STC1 and PFKFB4, for mRNA expression validation with real time QRT-PCR assays and found that the expression levels determined by real time QRT-PCR were consistent with the RNAseq data. Further studies involving downregulation of ARHGAP9 with a specific siRNA showed that ARHGAP9 altered the cellular sensitivity of Y79 cells to etoposide and carboplatin. CONCLUSION: Our initial findings provided a genomic view of the transcription profiles of etoposide-induced acquired resistance in RB. Follow-up studies indicated that ARHGAP9 might be a chemoresistance biomarker in RB, providing insight into potential therapeutic targets for overcoming acquired chemoresistance in RB. These findings can aid in understanding and overcoming chemoresistance during treatment of RB in the clinic.

3.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 130-135, 2020 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-32027265

RESUMO

OBJECTIVE: To study the expression level of TGFß1 and VEGF gene in patients with acute myeloid leukemia (AML) and its clinical prognostic value. METHODS: Seventy-eight AML patients treated in our hospital from July 2016 to September 2018 were selected. After isolation of bone marrow mononuclear cells from the patients, the levels of TGFß1 and VEGF genes were detected by RT-PCR, and the correlation of TGFß1 with VEGF genes and clinical characteristics of AML patients was analyzed. OS and EFS of the patients were evaluated by Kaplan-Meier, and Cox risk ratio model was used to analyze the prognostic risk factors of AML patients. RESULTS: The relative expression level of TGFß1 gene in AML patients was 0.32±0.04, which was significantly lower than that in control group (P<005). The relative expression level of vascular endothelial growth factor(VEGF) gene in the patients was 2.65±0.15, which was significantly higher than that in the control group (P<0.05). The levels of TGFß1 and VEGF genes significantly correlated with leukocyte count, hemoglobin, platelet and peripheral blast levels in AML patients (P<0.05). The level of TGFß1 in AML patients with complete remission was higher than that in patients with partial remission or non-remission (P<0.05). The level of TGFß1 in AML patients with partial remission was significantly higher than that in patients with non-remission (P<0.05). The level of VEGF in AML patients with complete remission was lower than at in patients with partial remission or non-remission (P<0.05). The level of VEGF in AML patients with partial remission was significantly lower than that in patients with non-remission (P<0.05). Kaplan-Meier survival analysis showed that OS and DFS in AML patients with high expression of TGFß1 were better than those in patients with low expression of TGFß1 (P<0.05), OS and DFS in AML patients with low expression of VEGF were better than those in patients with high expression of VEGF (P<0.05). Multivariate Cox regression analysis showed that platelet, TGFß1 and VEGF gene were independent influencing factors of OS (P<0.05). Leukocyte, TGFß1 and VEGF gene were independent influencing factors of DFS (P<0.05). CONCLUSION: Decreased expression of TGFß1 and increased expression of VEGF gene in AML patients closely relate to the poor prognosis of AML patients, which can provide reference for improving clinical efficacy of AML patients.


Assuntos
Leucemia Mieloide Aguda , Fator de Crescimento Transformador beta1/genética , Fator A de Crescimento do Endotélio Vascular/genética , Humanos , Estimativa de Kaplan-Meier , Leucemia Mieloide Aguda/genética , Prognóstico , Indução de Remissão
4.
Drug Deliv ; 27(1): 309-322, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32037895

RESUMO

Amentoflavone, robustaflavone, 2″,3″-dihydro-3',3‴-biapigenin, 3',3‴-binaringenin, and delicaflavone are five major hydrophobic components in the total biflavonoids extract from Selaginella doederleinii (TBESD) that display favorable anticancer properties. The purpose of this study was to develop a new oral delivery formulation to improve the solubilities, dissolution rates, and oral bioavailabilities of the main ingredients in TBESD by the solid dispersion technique. Solid dispersions of TBESD with various hydrophilic polymers were prepared, and different technologies were applied to select the suitable carrier and method. TBESD amorphous solid dispersion (TBESD-ASD) with polyvinylpyrrolidone K-30 was successfully prepared by the solvent evaporation method. The physicochemical properties of TBESD-ASD were investigated by scanning electron microscopy, differential scanning calorimetry, and Fourier-transform infrared spectroscopy. As a result, TBESD was found to be molecularly dispersed in the amorphous carrier. The solubilities and dissolution rates of all five ingredients in the TBESD-ASD were significantly increased (nearly 100% release), compared with raw TBESD. Meanwhile, TBESD-ASD showed good preservation stability for 3 months under accelerated conditions of 40 °C and 75% relative humidity. A subsequent pharmacokinetic study in rats revealed that Cmax and AUC0-t of all five components were significantly increased by the solid dispersion preparation. An in vivo study clearly revealed that compared to raw TBESD, a significant reduction in tumor size and microvascular density occurred after oral administration of TBESD-ASD to xenograft-bearing tumor mice. Collectively, the developed TBESD-ASD with the improved solubility, dissolution rates and oral bio-availabilities of the main ingredients could be a promising chemotherapeutic agent for cancer treatment.

5.
J Am Chem Soc ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32045234

RESUMO

Highly luminescent inks are desirable for various applications such as decorative coating, art painting, and anticounterfeiting, to name a few. However, present inks display low photoluminescent efficiency requiring a strong excitation light to make them glow. Here, we report a highly luminescent ink based on the copper-iodide/1-Propyl-1,4-diazabicyclo[2.2.2]octan-1-ium (Cu4I6(pr-ted)2) hybrid cluster with a quantum efficiency exceeding 98%. Under the interaction between the Cu4I6(pr-ted)2 hybrid cluster and polyvinylpyrrolidone (PVP), the highly luminescent Cu4I6(pr-ted)2/PVP ink can be facilely prepared via the one-pot solution synthesis. The obtained ink exhibits strong green light emission that originates from the efficient phosphorescence of Cu4I6(pr-ted)2 nanocrystals. Attractively, the ink displays high conversion efficiency for the ultraviolet light to bright green light emission due to its wide Stokes shift, implying great potential for anticounterfeiting and luminescent solar concentrator coating.

6.
Bioresour Technol ; 304: 122938, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32062393

RESUMO

Extracellular DNA (exDNA) can induce bias when evaluating the microbiota in wastewater treatment systems, particularly when cell lysis caused by thermal hydrolysis pretreatment (THP) releasing abundant DNA. However, the influence of such exDNA is still unknown. Accordingly, this study applied a pretreatment strategy for DNA extraction with proteinase K and DNase Ⅰ to minimize the influence of exDNA when evaluating the sludge microbiota. Lactobacillus and Peptostreptococcus were confirmed as the main THP-resistant microorganisms. Gram-positive bacteria were more resistant to THP, implying that the presence of a cell wall could promote THP resistance in bacteria. Moreover, the ability to form spores did not affect the resistance of bacteria to THP. These findings showed that resistant microbiota could be effectively evaluated by excluding exDNA, which can provide important insights into the understanding of microbiota dynamic and the effects of pretreatment on the precision of microbiota analysis in sludge.


Assuntos
Microbiota , Eliminação de Resíduos Líquidos , Anaerobiose , DNA , Hidrólise , Esgotos
7.
Vet Res ; 51(1): 26, 2020 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-32093767

RESUMO

Probiotic pretreatment is an effective non-antibiotic strategy for preventing or controlling Salmonella infections. We found that Lactobacillus johnsonii L531, isolated from the colon of a clinically healthy weaned piglet, effectively prevented infection with Salmonella enterica serovar Infantis in a pig model. Newly weaned piglets were intragastrically administered Lactobacillus johnsonii L531 at 1.0 × 1010 CFU/day for 1 week before S. Infantis challenge. Pretreatment with L. johnsonii L531 lessened the severity of diarrhea and ileal inflammation in S. Infantis-infected piglets. Lactobacilli were more abundant in the ileum than jejunum after L. johnsonii L531 pretreatment. Treatment with L. johnsonii L531 reduced the abundance of total bacteria in the ileal mucosa and the production of lipocalin 2 in the jejunum of piglets challenged with Salmonella. Both intestinal morphology and transmission electron microscopy results indicated that L. johnsonii L531 alleviated intestinal tissue damage following S. Infantis challenge, especially in the villus and endoplasmic reticulum (ER). ER stress induced by S. Infantis was attenuated by L. johnsonii L531 treatment. The number of CD4- CCR6+ T cells decreased following S. Infantis challenge, but the percentage of CCR6- IFNγ+ T cells in peripheral blood increased. In intestinal mesenteric lymph nodes, S. Infantis increased the proportion of CCR6+ IFNγ+ T cells, whereas L. johnsonii L531 induced an increase in the proportion of CD4+ CCR6+ T cells in response to S. Infantis infection. Our data thus suggest that L. johnsonii L531 contributes to the maintenance of intestinal homeostasis by modulating T-cell responses and ER stress.

8.
Artigo em Inglês | MEDLINE | ID: mdl-32071057

RESUMO

The emergence and dissemination of carbapenem-resistant Enterobacteriaceae (CRE) is a serious threat to public health (1).….

9.
J Am Chem Soc ; 142(6): 2956-2967, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-31902206

RESUMO

All-inorganic lead halide perovskite nanocrystals (NCs) are potential candidates for fabricating high-performance light-emitting diodes (LEDs) owing to their precisely tunable bandgaps, high photoluminescence (PL) efficiency, and excellent color purities. However, the performance of pure red (630-640 nm) all-inorganic perovskite LEDs is still limited by the halide segregation-induced instability of the electroluminescence (EL) of mixed halide CsPbI3-xBrx NCs. Herein, we report an effective approach to improving the EL stability of pure red all-inorganic CsPbI3-xBrx NC-based LEDs via the passivation of potassium bromide on NCs. By adding potassium oleate to the reaction system, we obtained potassium bromide surface-passivated (KBr-passivated) CsPbI3-xBrx NCs with pure red PL emission and a photoluminescence quantum yield (PLQY) exceeding 90%. We determine that most potassium ions present on the surface of NCs bind with bromide ions and thus demonstrate that potassium bromide surface passivation of NCs can both improve the PL stability and inhibit the halide segregation of NCs. Using KBr-passivated CsPbI3-xBrx NCs as an emitting layer, we fabricated stable and pure red perovskite LEDs with emission at 637 nm, showing a maximum brightness of 2671 cd m-2, maximum external quantum efficiency of 3.55%, and good EL stability. The proposed KBr-passivated NC strategy will open a new avenue for fabricating efficient, stable, and tunable pure color perovskite NC LEDs.

10.
Waste Manag ; 103: 334-341, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31923840

RESUMO

Thermal treatment could effectively realize the detoxification of heavy metals in municipal solid waste incineration (MSWI) fly ash through the approach of removal or stabilization process. To lower the operating temperature and suppress the evaporation of heavy metals, a molten salts (NaCl-CaCl2) thermal treatment method was proposed for the detoxification of heavy metals from MSWI fly ash at a relatively mild condition (600/800 °C). The fate of heavy metals during the heating process and their stabilization properties in the remained ash slag after molten salts thermal treatment were investigated. The results showed that, compared with the traditional thermal treatment, heavy metals were more easily chlorinated by the means of molten salts thermal treatment. The well distributed chloride in molten salts facilitated the direct chlorination of PbO/CdO. Furthermore, Al2O3 in ash enhanced the indirect chlorination of CuO/PbO/CdO, except for ZnO. In contrast, SiO2 showed better performance in promoting the indirect chlorination of heavy metal oxides. Meanwhile, some Zn2+ was precipitated from molten salts as Si/Al-Zn composite oxides through the interactions with ash containing Si/Al oxides. On the other hand, the dissolved heavy metals in molten salts showed a good thermal stability during the thermal treatment. The volatilization fractions of all detected heavy metals were less than 5%. After the molten salts thermal treatment, heavy metals in the ash slag were well stabilized and the amount of heavy metals leached was significantly lower than that from the raw fly ash.

11.
J Antimicrob Chemother ; 75(4): 868-872, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31971232

RESUMO

OBJECTIVES: To identify the genetic context and the transferability of the multiresistance gene lsa(E) in Listeria monocytogenes. METHODS: MICs were determined by broth microdilution. Transferability of lsa(E) was investigated by conjugation, electrotransformation and natural transformation. The lsa(E)-carrying plasmid was sequenced using the Illumina MiSeq and PacBio RSII platforms. The presence of translocatable units (TUs) was examined by PCR. RESULTS: The 85 555 bp non-conjugative multiresistance plasmid pNH1 from L. monocytogenes harboured nine antimicrobial resistance genes including a multiresistance gene cluster, consisting of the genes aphA3, erm(B), aadE, spw, lsa(E) and lnu(B), and in addition the genes dfrG, tet(S) and catA8 were also located on plasmid pNH1 The multiresistance gene cluster, and each of the genes tet(S), catA8 and cadA were flanked by IS1216 elements. PCR identified four types of TUs, consisting of either the multiresistance gene cluster and one copy of IS1216, the catA8 gene and one copy of IS1216, or both, but also the tet(S) gene and one copy of IS1216, respectively. Natural transformation into Streptococcus mutans UA159 yielded transformants that harboured a novel 13 208 bp transposon, designated Tn6659. This transposon consisted of the multiresistance gene cluster bounded by IS1216 copies. All transformants displayed elevated MICs of the respective antimicrobial agents. At the integration site in the transformants, 8 bp direct target duplications (5'-ATTCAAAC-3') were found immediately up- and downstream of Tn6659. CONCLUSIONS: To the best of our knowledge, this is the first report of this novel multiresistance gene cluster and the gene catA8, flanked by IS1216 elements located on a plasmid of L. monocytogenes. Moreover, a novel functionally active multiresistance transposon was identified.

12.
Surg Innov ; 27(2): 181-186, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31920153

RESUMO

Background. Transanal minimally invasive surgery (TAMIS) was developed as a less aggressive alternative treatment for rectal lesions. The purpose of this study was to report the results of robotic TAMIS for such patients. Methods. Patients eligible for TAMIS were operated on using the da Vinci robotic surgical system and GelPOINT Path Transanal Access Platform. Patient demographics, lesion characteristics, perioperative data, complications, and follow-up of all patients were recorded retrospectively. Results. Between March 2015 and August 2018, 24 patients underwent robotic TAMIS by using the da Vinci Si or Xi. The median operative time was 129.6 minutes, and the estimated blood loss was minimal. The mean length of hospital stay was 4.6 days, with no operative complications and no 30-day mortality. There were no statistically significant differences in clinical results and pathological outcomes between the 2 generations of da Vinci systems. Conclusions. With the use of robotic technology, transanal local excision for rectal lesions can be performed with relative ease and safety and can be potentially decreasing the morbidity associated with more aggressive surgical techniques.

13.
Chemosphere ; 241: 125107, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31683450

RESUMO

The disposal of the hazardous municipal solid waste (MSW) incineration fly ash is a critical environmental issue in China and the high contents of salts in the fly ash make the ash disposal extremely difficult. The present study proposes a novel method for the salts removal from MSW incineration fly ash using molten carbonates and chlorides at moderate temperatures from 773 K to 1073 K. The results showed that molten salts could effectively extract alkali and alkaline earth metals chlorides and sulfates from the fly ash. Other ash components, like Si/Al-compounds, were precipitated from the molten salts and concentrated in residues. By comparison, molten carbonates showed greater capability in the salts extraction while molten chlorides showed better selectivity in chlorides removal from MSW incineration fly ash. These findings suggest that the optimization of molten salts system could further prove the potential applicability of molten salts thermal treatment method for the salts removal from MSW incineration fly ash.


Assuntos
Cinza de Carvão/química , Temperatura Alta , Sais/isolamento & purificação , Álcalis , China , Cloretos/isolamento & purificação , Incineração , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Sulfatos/isolamento & purificação
14.
Biochem Pharmacol ; 171: 113680, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669234

RESUMO

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide and tends to have drug resistance. Delicaflavone (DLF), a novel anticancer agent of biflavonoid from Selaginella doederleinii Hieron, showed strong anti-CRC activities, which has not yet been reported. In this study, we investigated the effects and possible anti-CRC mechanism of DLF in vitro and in vivo. It was shown that DLF significantly inhibited the cells viability and induced G2/M phase arrest, apoptosis, the loss of mitochondrial membrane potential (Δψm), generation of ROS and increase of intracellular Ca2+ in HT29 and HCT116 cells by MTT assay, TEM, flow cytometry and inverted fluorescence microscope. Western blot and qPCR assays results further confirmed DLF induced caspase-dependent apoptosis and inhibited PI3K/AKT/mTOR and Ras/MEK/Erk signaling pathways in CRC cells. Meanwhile, DLF significantly suppressed the tumor growth via activation of Caspase-9 and Caspase-3 protein and decrease of ki67 and CD34 protein without apparent side effects in vivo. In summary, these results indicated DLF induced ROS-mediated cell cycle arrest and apoptosis through ER stress and mitochondrial pathway accompanying with the inhibition of PI3K/AKT/mTOR and Ras/MEK/Erk signaling cascade. Thus DLF could be a potential therapeutic agent for CRC.

15.
Biosci Rep ; 40(1)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31778149

RESUMO

BACKGROUND: Tuberculous meningitis (TBM) is one of the most serious types of extrapulmonary tuberculosis. However, low sensitivity of culture of cerebrospinal fluid (CSF) increases the difficulty in clinical diagnosis, leading to diagnostic delay, and misdiagnosis. Xpert MTB/RIF assay is a rapid and simple method to detect tuberculosis. However, the efficacy of this technique in diagnosing TBM remains unclear. Therefore, a meta-analysis was conducted to evaluate the diagnostic efficacy of Xpert MTB/RIF for TBM, which may enhance the development of early diagnosis of TBM. METHODS: Relevant studies in the PubMed, Embase, and Web of Science databases were retrieved using the keywords 'Xpert MTB/RIF', 'tuberculous meningitis (TBM)'. The pooled sensitivity, pooled specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, summary receiver operator characteristic curve, and area under the curve (AUC) of Xpert MTB/RIF were determined and analyzed. RESULTS: A total of 162 studies were enrolled and only 14 met the criteria for meta-analysis. The overall pooled sensitivity of Xpert MTB/RIF was 63% [95% confidence interval (CI), 59-66%], while the overall pooled specificity was 98.1% (95% CI, 97.5-98.5%). The pooled values of positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 20.91% (12.71-52.82%), 0.40% (0.32-0.50%), and 71.49% (32.64-156.56%), respectively. The AUC was 0.76. CONCLUSIONS: Xpert MTB/RIF exhibited high specificity in diagnosing TBM in CSF samples, but its sensitivity was relatively low. It is necessary to combine other high-sensitive detection methods for the early diagnosis of TBM. Moreover, the centrifugation of CSF samples was found to be beneficial in improving the sensitivity.

16.
Nano Lett ; 20(1): 677-685, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31825636

RESUMO

Lithium cobalt oxide (LiCoO2) possesses an attractive theoretical specific capacity (274 mAh g-1) and high discharge voltage (∼4.2 V vs Li+/Li). However, only a half of the theoretical capacity of LiCoO2 is available in commercialized lithium ion batteries because of the intrinsic structural instability and detrimental interface of LiCoO2 at the charging voltage over 4.2 V. Here, a facile blow-spinning synthetic method is developed to realize precise doping and simultaneous self-assembly coating of LiCoO2 particles, achieving a record performance among present LiCoO2 cathodes. Owing to the spatial confinement effect of microfibers fabricated by blow-spinning, homogeneously Mn and La doped in the LiCoO2 host and uniformly Li-Ti-O segregated at the LiCoO2 surface can be realized in every batch of samples. It is demonstrated that the Mn and La codoping can suspend the intrinsic instability and increase the Li+ diffusivity of the LiCoO2 host, and the Ti-based coating can stabilize the interface of LiCoO2 particles at the charging voltage up to 4.5 V. As a result, the obtained comodified LiCoO2 cathode shows the best rate performance (1.85 mAh cm-2 at 2C) and longest cycling stability under an areal capacity of 2.04 mAh cm-2 (83% capacity retention over 300 cycles at 0.3C), in comparison to previously reported LiCoO2 cathodes.

17.
New Phytol ; 226(1): 142-155, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31745997

RESUMO

Root hair development is crucial for phosphate absorption, but how phosphorus deficiency affects root hair initiation and elongation remains unclear. We demonstrated the roles of auxin efflux carrier PIN-FORMED2 (PIN2) and phospholipase D (PLD)-derived phosphatidic acid (PA), a key signaling molecule, in promoting root hair development in Arabidopsis thaliana under a low phosphate (LP) condition. Root hair elongation under LP conditions was greatly suppressed in pin2 mutant or under treatment with a PLDζ2-specific inhibitor, revealing that PIN2 and polar auxin transport and PLDζ2-PA are crucial in LP responses. PIN2 was accumulated and degraded in the vacuole under a normal phosphate (NP) condition, whereas its vacuolar accumulation was suppressed under the LP or NP plus PA conditions. Vacuolar accumulation of PIN2 was increased in pldζ2 mutants under LP conditions. Increased or decreased PIN2 vacuolar accumulation is not observed in sorting nexin1 (snx1) mutant, indicating that vacuolar accumulation of PIN2 is mediated by SNX1 and the relevant trafficking process. PA binds to SNX1 and promotes its accumulation at the plasma membrane, especially under LP conditions, and hence promotes root hair development by suppressing the vacuolar degradation of PIN2. We uncovered a link between PLD-derived PA and SNX1-dependent vacuolar degradation of PIN2 in regulating root hair development under phosphorus deficiency.

18.
J Hazard Mater ; 385: 121515, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31718810

RESUMO

Wastewater treatment systems are critical microbial sources for urban air and play important roles in public health. In this study, bacterial communities in particulate matters (PM2.5, PM10) from wastewater/sludge treatment facilities of two full-scale wastewater treatment plants were analyzed by 16S rRNA amplicon sequencing. Compared to the background ambient air, Campylobacteriadeceae, Aeromonadaceae, and Chlostridiaceae were the most enriched bacteria above wastewater treatment facilities. In sludge dewatering facilities, Comamonadaceae, Chitinophagaceae, Caldilineaceae, Mycobacteriaceae, Methylocystaceae, Microbacteriaceae, Cryomorphaceae, and uncultured Class OPB56 were the most enriched. The dynamic bacterial compositions in aerosols were contributed by aerosolization and dispersion. Principal coordinate analysis and clustering analysis showed that the aerosol bacterial community from indoor sludge treatment were closely clustered with that of sludge, indicating that aerosolization dominated the indoor environments. In contrast, aerosols from outdoor wastewater treatment facilities clustered with background ambient aerosols, indicating that outdoor aerosol bacterial communities were mainly governed by dispersion. Aerosolization factor (the ratio of bacteria abundance in aerosols to those in wastewater/sludge) was used to evaluate the aerosolization potential and survival of bacteria. Rhodocyclaceae, Arcobacter, Comamonadaceae, Mycobacterium, and Citrobacter were not only preferentially aerosolized from wastewater/sludge, but also sustainable during dispersion in ambient air.

19.
Plant Biotechnol J ; 18(1): 83-95, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31131526

RESUMO

Pyrophosphate-fructose 6-phosphate 1-phosphotransferase (PFP1) reversibly converts fructose 6-phosphate and pyrophosphate to fructose 1, 6-bisphosphate and orthophosphate during glycolysis, and has diverse functions in plants. However, mechanisms underlying the regulation of starch metabolism by PFP1 remain elusive. This study addressed the function of PFP1 in rice floury endosperm and defective grain filling. Compared with the wild type, pfp1-3 exhibited remarkably low grain weight and starch content, significantly increased protein and lipid content, and altered starch physicochemical properties and changes in embryo development. Map-based cloning revealed that pfp1-3 is a novel allele and encodes the regulatory ß-subunit of PFP1 (PFP1ß). Measurement of nicotinamide adenine dinucleotide (NAD+) showed that mutation of PFP1ß markedly decreased its enzyme activity. PFP1ß and three of four putative catalytic α-subunits of PFP1, PFP1α1, PFP1α2, and PFP1α4, interacted with each other to form a heterotetramer. Additionally, PFP1ß, PFP1α1 and PFP1α2 also formed homodimers. Furthermore, transcriptome analysis revealed that mutation of PFP1ß significantly altered expression of many essential enzymes in starch biosynthesis pathways. Concentrations of multiple lipid and glycolytic intermediates and trehalose metabolites were elevated in pfp1-3 endosperm, indicating that PFP1 modulates endosperm metabolism, potentially through reversible adjustments to metabolic fluxes. Taken together, these findings provide new insights into seed endosperm development and starch biosynthesis and will help in the breeding of rice cultivars with higher grain yield and quality.

20.
Water Res ; 168: 115200, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31655440

RESUMO

H2-based autotrophic denitrification is promising to remove nitrate from water or wastewater lacking organic carbon sources, and pH is one of its most important process parameters. HCl and CO2 addition are known as adequate pH control methods for practical purposes. However, because of H2, added CO2 may participate in microbial metabolisms and affect denitrification mechanisms. Here, a combined micro-electrolysis and autotrophic denitrification (CEAD) reactor, in which H2 is generated based on galvanic-cell reactions between zero-valent iron and carbon, was optimized and continuously operated for 233 days by adding HCl or CO2 to control pH in the range of 7.2-8.2. Microbial communities were compared between the two pH-control methods through high-throughput sequencing of 16S rRNA, nirS, and nirK genes. Under a low COD/N ratio of 0.5 in the influent (with ∼36 mgNO3--N/L), when adding HCl, the total nitrogen (TN) removal efficiency reached 91.4% ±â€¯0.9% with a 28-h hydraulic retention time (HRT). When adding CO2, the TN removal efficiency was improved to 96.5% ±â€¯1.7% with 24-h HRT. Significant differences of 16S rRNA and nirS genes between the two pH-control stages indicated the variation of microbial communities and nirS-type denitrifiers. With HCl addition, Thiobacillus, unclassified Comamonadaceae, Arenimonas, Limnobacter, and Thermomonas, which were reported previously as likely autotrophic or heterotrophic denitrifiers, were most dominant in the biofilms. With CO2 addition, the biofilms became dominated by Anaerolineaceae and Methylocystaceae (related to organic carbon metabolism), Denitratisoma (likely heterotrophic denitrifier), and uncultured bacteria TK10 and AKYG587. The results suggest that the added CO2 not only contributed to pH control but also participated in microbial metabolisms. This study provides useful insights into microbial mechanisms and further optimization of H2-based autotrophic denitrification in water and wastewater treatment.


Assuntos
Desnitrificação , Microbiota , Processos Autotróficos , Reatores Biológicos , Dióxido de Carbono , Concentração de Íons de Hidrogênio , Nitratos , Nitrogênio , RNA Ribossômico 16S , Águas Residuárias
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