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1.
Small ; 20(15): e2307473, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009727

RESUMO

With the advent of wireless technology, magnetic-carbon composites with strong electromagnetic wave (EMW) absorption capability in low-/middle-frequency range are highly desirable. However, it remains challenging for rational construction of such absorbers bearing multiple magnetic components that show uniform distribution and favorable magnetic loss. Herein, a facile metal-oxo cluster (MOC) precursor strategy is presented to produce high-efficiency magnetic carbon composites. Nanosized MOC Fe15 shelled with organic ligands is employed as a novel magnetic precursor, thus allowing in situ formation and uniform deposition of multicomponent magnetic Fe/Fe3O4@Fe3C and Fe/Fe3O4 nanoparticles on graphene oxides (GOs) and carbon nanotubes (CNTs), respectively. Owing to the good dispersity and efficient magnetic-dielectric synergy, quaternary Fe/Fe3O4@Fe3C-GO exhibits strong low-frequency absorption with RLmin of -53.5 dB at C-band and absorption bandwidth covering 3.44 GHz, while ultrahigh RLmin of -73.2 dB is achieved at X-band for ternary Fe/Fe3O4-CNT. The high performance for quaternary and ternary composites is further supported by the optimal specific EMW absorption performance (-15.7 dB mm-1 and -31.8 dB mm-1) and radar cross-section reduction (21.72 dB m2 and 34.37 dB m2). This work provides a new avenue for developing lightweight low-/middle-frequency EMW absorbers, and will inspire the investigation of more advanced EMW absorbers with multiple magnetic components and regulated microstructures.

2.
BMC Palliat Care ; 23(1): 89, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38566178

RESUMO

BACKGROUND: A standardized national approach to routinely assessing palliative care patients helps improve patient outcomes. However, a quality improvement program-based on person centered outcomes within palliative care is lacking in Mainland China. The well-established Australian Palliative Care Outcome Collaboration (PCOC) national model improves palliative care quality. This study aimed to culturally adapt and validate three measures that form part of the PCOC program for palliative care clinical practice in China: The PCOC Symptom Assessment Scale (PCOC SAS), Palliative Care Problem Severity Scale (PCPSS), Palliative Care Phase. METHODS: A study was conducted on cross-cultural adaptation and validation of PCOC SAS, PCPSS and Palliative Care Phase, involving translation methods, cognitive interviewing, and psychometric testing through paired assessments. RESULTS: Cross-cultural adaptation highlighted the need to strengthen the link between the patient's care plan and the outcome measures to improve outcomes, and the concept of distress in PCOC SAS. Analysis of 368 paired assessments (n = 135 inpatients, 22 clinicians) demonstrated that the PCOC SAS and PCPSS had good and acceptable coherence (Cronbach's a = 0.85, 0.75 respectively). Palliative Care Phase detected patients' urgent needs. PCOC SAS and PCPSS showed fair discriminant and concurrent validity. Inter-rater reliability was fair for Palliative Care Phase (k = 0.31) and PCPSS (k = 0.23-0.30), except for PCPSS-pain, which was moderate (k = 0.53). CONCLUSIONS: The Chinese version of PCOC SAS, PCPSS, and Palliative Care Phase can be used to assess outcomes as part of routine clinical practice in Mainland China. Comprehensive clinical education regarding the assessment tools is necessary to help improve the inter-rater reliability.


Assuntos
Comparação Transcultural , Cuidados Paliativos , Humanos , Cuidados Paliativos/métodos , Psicometria , Reprodutibilidade dos Testes , Sistemas Automatizados de Assistência Junto ao Leito , Austrália , Avaliação de Resultados em Cuidados de Saúde/métodos , Inquéritos e Questionários
3.
Int J Mol Sci ; 25(14)2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-39062878

RESUMO

Cerasus humilis, a small shrub of the Cerasus genus within the Rosaceae family, is native to China and renowned for its highly nutritious and medicinal fruits, robust root system, and remarkable drought resistance. This study primarily employed association transcriptome and metabolome analyses to assess changes in abscisic acid (ABA) levels and identify key regulatory genes in C. humilis subjected to varying degrees of drought stress. Notably, we observed distinct alterations in transcription factors across different drought intensities. Specifically, our transcriptome data indicated noteworthy shifts in GATA, MYB, MYC, WRKY, C2H2, and bHLH transcription factor families. Furthermore, combined transcriptomic and metabolomic investigations demonstrated significant enrichment of metabolic pathways, such as 'Carbon metabolism', 'Biosynthesis of amino acids', 'Biosynthesis of cofactors', 'Phenylpropanoid biosynthesis', 'Starch and sucrose metabolism', and 'Plant hormone signal transduction' under moderate (Mod) or severe (Sev) drought conditions. A total of 11 candidate genes involved in ABA biosynthesis and signaling pathways were identified. The down-regulated genes included secoisolariciresinol dehydrogenase-like and PYL2. Conversely, genes including FAD-dependent urate hydroxylase-like, cytochrome P450 97B2, carotenoid cleavage dioxygenase 4 (CCD4), SnRK2.2, ABI 5-like protein 5, PP2C 51, and SnRK2.3, were up-regulated under Mod or Sev drought stress. This study lays the genetic foundation for ABA biosynthesis to enhance drought tolerance and provides genetic resources for plant genetic engineering and breeding efforts.


Assuntos
Ácido Abscísico , Secas , Regulação da Expressão Gênica de Plantas , Estresse Fisiológico , Transcriptoma , Ácido Abscísico/metabolismo , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Metaboloma/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Metabolômica/métodos , Perfilação da Expressão Gênica
4.
Palliat Support Care ; : 1-7, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587037

RESUMO

OBJECTIVES: Accurately assessing the self-efficacy levels of palliative care professionals' is crucial, as low levels of self-efficacy may contribute to the suboptimal provision of palliative care. However, there is currently lacking a reliable and valid instrument for evaluating the self-efficacy of palliative care practitioners in China. Therefore, this study aimed to translate, adapt, and validate the Palliative Care Self-Efficacy Scale (PCSS) among Chinese palliative care professionals. METHODS: This study involved the translation and cross-cultural adaptation of the PCSS, and the evaluation of its psychometric properties through testing for homogeneity, content validity, construct validity, known-groups validity, and reliability. RESULTS: A total of 493 palliative care professionals participated in this study. The results showed the critical ratio value of each item was >3 (p < 0.01), and the corrected item-total correlation coefficients of all items ranged from 0.733 to 0.818, indicating a good homogeneity of the items with the scale. Additionally, the scale was shown to have good validity, with item-level content validity index ranged from 0.857 to 1.000, and scale-level content validity index/Ave was 0.956. The exploratory factor analysis and confirmatory factor analysis (CFA) confirmed the 2-factor structure of the Chinese version of PCSS (C-PCSS), explaining 74.19% of the variance. CFA verified that the 2-factor model had a satisfactory model fit, with χ2/df = 2.724, RMSEA = 0.084, GFI = 0.916, CFI = 0.967, and TLI = 0.952. The known-groups validity of C-PCSS was demonstrated good with its sensitive in differentiating levels of self-efficacy between professionals with less than 1 year of palliative care experience (p < 0.001) or without palliative care training (p = 0.014) and their counterparts. Furthermore, the C-PCSS also exhibited an excellent internal consistency, with the Cronbach's α for the total scale of 0.943. SIGNIFICANCE OF RESULTS: The findings from this study affirmed good validity and reliability of the C-PCSS. It can be emerged as a valuable and reliable instrument for assessing the self-efficacy levels of palliative care professionals in China.

5.
BMC Plant Biol ; 23(1): 209, 2023 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-37085761

RESUMO

BACKGROUND: Genes with valine glutamine (VQ) motifs play an essential role in plant growth, development, and resistance to biotic and abiotic stresses. However, little information on the VQ genes in sweetpotato and other Ipomoea species is available. RESULTS: This study identified 55, 58, 50 and 47 VQ genes from sweetpotato (I. batatas), I.triflida, I. triloba and I. nil, respectively. The phylogenetic analysis revealed that the VQ genes formed eight clades (I-VII), and the members in the same group exhibited similar exon-intron structure and conserved motifs distribution. The distribution of the VQ genes among the chromosomes of Ipomoea species was disproportional, with no VQ genes mapped on a few of each species' chromosomes. Duplication analysis suggested that segmental duplication significantly contributes to their expansion in sweetpotato, I.trifida, and I.triloba, while the segmental and tandem duplication contributions were comparable in I.nil. Cis-regulatory elements involved in stress responses, such as W-box, TGACG-motif, CGTCA-motif, ABRE, ARE, MBS, TCA-elements, LTR, and WUN-motif, were detected in the promoter regions of the VQ genes. A total of 30 orthologous groups were detected by syntenic analysis of the VQ genes. Based on the analysis of RNA-seq datasets, it was found that the VQ genes are expressed distinctly among different tissues and hormone or stress treatments. A total of 40 sweetpotato differentially expressed genes (DEGs) refer to biotic (sweetpotato stem nematodes and Ceratocystis fimbriata pathogen infection) or abiotic (cold, salt and drought) stress treatments were detected. Moreover, IbVQ8, IbVQ25 and IbVQ44 responded to the five stress treatments and were selected for quantitative reverse-transcription polymerase chain reaction (qRT-PCR) analysis, and the results were consistent with the transcriptome analysis. CONCLUSIONS: Our study may provide new insights into the evolution of VQ genes in the four Ipomoea genomes and contribute to the future molecular breeding of sweetpotatoes.


Assuntos
Ipomoea batatas , Ipomoea , Ipomoea/genética , Glutamina/genética , Valina/genética , Filogenia , Genoma , Ipomoea batatas/genética , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética
6.
Inorg Chem ; 62(19): 7376-7384, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-37134020

RESUMO

Copper-based halides have been found to be a new family of lead-free materials with high stability and superior optoelectrical properties. In this work, we report the photoluminescence of the known (C8H14N2)CuBr3 and the discovery of three new compounds, (C8H14N2)CuCl3, (C8H14N2)CuCl3·H2O, and (C8H14N2)CuI3, which all exhibit efficient light emissions. All these compounds have monoclinic structures with the same space group (P21/c) and zero-dimensional (0D) structures, which can be viewed as the assembly of promising aromatic molecules and different copper halide tetrahedrons. Upon the irradiation of deep ultraviolet light, (C8H14N2)CuCl3, (C8H14N2)CuBr3,, and (C8H14N2)CuI3 show green emission peaking at ∼520 nm with a photoluminescent quantum yield (PLQY) of 3.38, 35.19, and 17.81%, while (C8H14N2)CuCl3·H2O displays yellow emission centered at ∼532 nm with a PLQY of 2.88%. A white light-emitting diode (WLED) was successfully fabricated by employing (C8H14N2)CuBr3 as a green emitter, demonstrating the potential of copper halides for applications in the green lighting field.

7.
Nano Lett ; 22(12): 4979-4984, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35639704

RESUMO

The traditional hardness-toughness tradeoff poses a substantial challenge for the development of superhard materials. Due to strong covalent bonds and intrinsic brittleness, the full advantage of microstructure engineering for enhanced mechanical properties requires further exploration in superhard materials. Here heterogeneous diamond-cBN composites were synthesized from a carefully prepared precursor (hBN microflakes uniformly wrapped by onion carbon nanoparticles) through phase transitions under high pressure and high temperature. The synthesized composites inherit the architecture of the precursors: cBN regions with an anisotropic profile that spans several micrometers laterally and several hundred nanometers in thickness are embedded in a nanograined diamond matrix with high-density nanotwins. A significantly high fracture toughness of 16.9 ± 0.8 MPa m1/2 is achieved, far beyond those of single-crystal diamond and cBN, without sacrificing hardness. A detailed TEM analysis revealed multiple toughening mechanisms closely related to the microstructure. This work sheds light on microstructure engineering in superhard materials for excellent mechanical properties.

8.
Angew Chem Int Ed Engl ; 62(39): e202308344, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37485998

RESUMO

The atom-cluster interaction has recently been exploited as an effective way to increase the performance of metal-nitrogen-carbon catalysts for oxygen reduction reaction (ORR). However, the rational design of such catalysts and understanding their structure-property correlations remain a great challenge. Herein, we demonstrate that the introduction of adjacent metal (M)-N4 single atoms (SAs) could significantly improve the ORR performance of a well-screened Fe atomic cluster (AC) catalyst by combining density functional theory (DFT) calculations and experimental analysis. The DFT studies suggest that the Cu-N4 SAs act as a modulator to assist the O2 adsorption and cleavage of O-O bond on the Fe AC active center, as well as optimize the release of OH* intermediates to accelerate the whole ORR kinetic. The depositing of Fe AC with Cu-N4 SAs on nitrogen doped mesoporous carbon nanosheet are then constructed through a universal interfacial monomicelles assembly strategy. Consistent with theoretical predictions, the resultant catalyst exhibits an outstanding ORR performance with a half-wave potential of 0.92 eV in alkali and 0.80 eV in acid, as well as a high power density of 214.8 mW cm-2 in zinc air battery. This work provides a novel strategy for precisely tuning the atomically dispersed poly-metallic centers for electrocatalysis.

9.
Nano Lett ; 21(1): 700-708, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33301324

RESUMO

The greatest challenge for lithium-sulfur (Li-S) batteries application is the development of cathode hosts to address the low conductivity, huge volume change, and shuttling effect of sulfur or lithium polysulfides (LiPs). Herein, we demonstrate a composite host to circumvent these problems by confining sub-nanometric manganous oxide clusters (MOCs) in nitrogen doped mesoporous carbon nanosheets. The atomic structure of MOCs is well-characterized and optimized via the extended X-ray absorption fine structure analysis and density functional theory (DFT) calculations. Benefiting from the unique design, the assembled Li-S battery displays remarkable electrochemical performances including a high reversible capacity (990 mAh g-1 after 100 cycles at 0.2 A g-1) and a superior cycle life (60% retention over 250 cycles at 2 A g-1). Both the experimental results and DFT calculations demonstrate that the well-dispersed MOCs could significantly promote the chemisorption of LiPs, thus greatly improving the capacity and rate performance.

10.
Small ; 17(9): e1904022, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-31643131

RESUMO

Mesoporous materials have drawn more and more attention in the field of biosensors due to their high surface areas, large pore volumes, tunable pore sizes, as well as abundant frameworks. In this review, the progress on mesoporous materials-based biosensors from enzymatic to nonenzymatic are highlighted. First, recent advances on the application of mesoporous materials as supports to stabilize enzymes in enzymatic biosensing technology are summarized. Special emphasis is placed on the effect of pore size, pore structure, and surface functional groups of the support on the immobilization efficiency of enzymes and the biosensing performance. Then, the development of a nonenzymatic strategy that uses the intrinsic property of mesoporous materials (carbon, silica, metals, and composites) to mimic the behavior of enzymes for electrochemical sensing of some biomolecules is discussed. Finally, the challenges and perspective on the future development of biosensors based on mesoporous materials are proposed.


Assuntos
Técnicas Biossensoriais , Técnicas Eletroquímicas , Metais , Dióxido de Silício
11.
Environ Sci Technol ; 55(4): 2652-2661, 2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33337860

RESUMO

Clean water production calls for highly efficient and less energy-intensive technologies. Herein, a novel concept of a sequential ultrafiltration-catalysis membrane is developed by loading Co3O4/C@SiO2 yolk-shell nanoreactors into the fingerlike channels of a polymeric ultrafiltration membrane. Such a sequenced structure design successfully integrates selective separation with peroxymonosulfate-based catalysis to prepare a functionalized molecular sieve membrane, which exhibits excellent decontamination performance toward multipollutants by filtering the water matrices containing humic acid (HA) and bisphenol A (BPA). In this study, 100% rejection of HA and 95% catalytic degradation of BPA were achieved under a low pressure of 0.14 MPa and an ultrahigh flux of 229 L m-2 h-1, corresponding to a retention time of 3.1 s. Notably, the removal performance of multiple pollutants essentially depends on the ordered arrangement of ultrafiltration and catalysis. Moreover, the flow-through process demonstrated significant enhancement of BPA degradation kinetics, which is 21.9 times higher than that of a conventional batch reactor. This study provides a novel strategy for excellent removal of multiple pollutants in water.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Purificação da Água , Catálise , Dióxido de Silício , Ultrafiltração , Água , Poluentes Químicos da Água/análise
12.
BMC Public Health ; 21(1): 223, 2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33504346

RESUMO

BACKGROUND: Few studies investigated the associations between dietary patterns and overweight/obesity among Chinese preschool children. Thus, the study aims to explore dietary patterns and their associations with overweight/obesity among preschool children in the Dongcheng District of Beijing. METHODS: With a stratified proportionate cluster sampling, the study included 3373 pairs of preschool children and their guardians. Children's weight and height were measured by school nurses, and their food and beverage consumption frequencies were reported by guardians via a food frequency questionnaire. Children's age, gender, physical activity time, and sedentary time, as well as their parents' highest level of educational attainment, occupation, weight, and height were also collected. Dietary patterns were identified through exploratory factor analysis. Among these identified dietary patterns, the one with the largest factor score was defined as the predominant dietary pattern for each child. The associations between predominant dietary patterns and overweight/obesity were tested by two-level random-intercept logistic models with cluster-robust standard errors. RESULTS: Four dietary patterns, i.e., a "Sugar-sweetened beverage (SSB) and snack" pattern, a "Chinese traditional" pattern, a "Health conscious" pattern, and a "Snack" pattern, were identified. Among the children, 21.02% (95% CI: 19.68 to 22.43%) were predominated by the "SSB and snack" pattern, 27.78% (95% CI: 26.29 to 29.32%) by the "Chinese traditional" pattern, 24.90% (95% CI: 23.47 to 26.39%) by the "Health conscious" pattern, and 26.30% (95% CI: 24.84 to 27.81%) by the "Snack" pattern. After controlling for potential confounders, the "SSB and snack" pattern characterized by fresh fruit/vegetable juice, flavored milk drinks, carbonated drinks, flavored fruit/vegetable drinks, tea drinks, plant-protein drinks, puffed foods, fried foods, and Western fast foods was associated with a higher risk of overweight/obesity (OR: 1.61, 95% CI:1.09 to 2.38), compared with the "Chinese traditional" pattern. CONCLUSIONS: The preference for dietary patterns with high energy density but low nutritional value was prevalent among preschool children in the Dongcheng District of Beijing. Comprehensive measures to simultaneously reduce consumption of SSBs and unhealthy snacks among preschool children should be taken urgently to address the childhood obesity problem in China, particularly in metropolises.


Assuntos
Dieta , Sobrepeso , Animais , Pequim/epidemiologia , Bebidas , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Comportamento Alimentar , Humanos , Sobrepeso/epidemiologia
13.
Rare Metals ; 40(8): 2017-2025, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679100

RESUMO

Owing to their high performance and earth abundance, copper sulfides (Cu2-x S) have attracted wide attention as a promising medium-temperature thermoelectric material. Nanostructure and grain-boundary engineering are explored to tune the electrical transport and phonon scattering of Cu2-x S based on the liquid-like copper ion. Here multiscale architecture-engineered Cu2-x S are fabricated by a room-temperature wet chemical synthesis combining mechanical mixing and spark plasma sintering. The observed electrical conductivity in the multiscale architecture-engineered Cu2-x S is four times as much as that of the Cu2-x S sample at 800 K, which is attributed to the potential energy filtering effect at the new grain boundaries. Moreover, the multiscale architecture in the sintered Cu2-x S increases phonon scattering and results in a reduced lattice thermal conductivity of 0.2 W·m-1·K-1 and figure of merit (zT) of 1.0 at 800 K. Such a zT value is one of the record values in copper sulfide produced by chemical synthesis. These results suggest that the introduction of nanostructure and formation of new interface are effective strategies for the enhancement of thermoelectric material properties. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s12598-020-01698-6) contains supplementary material, which is available to authorized users.

14.
Environ Sci Technol ; 54(16): 10289-10300, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32614573

RESUMO

Selective removal of organic pollutants from surface water with high efficiency is crucial in water purification. Here, yolk-shell Co/C nanoreactors (YSCCNs) are facilely synthesized via pyrolysis of controllably etched ZIF-67 by tannic acid, and their degradation performance on multiple pollutants is demonstrated. To present the structure-performance relationship between the designed nanocatalyst and the selective removal of organic pollutants, bisphenol A (BPA) was selected as the targeted pollutant with coexistence of humus acid (HA). For comparison, solid and hollow ZIF-67 derived Co/C nanoparticles denoted as SCCNs and HCCNs, were also tested. The results show that YSCCNs exhibit enhanced BPA degradation rate of 0.32 min-1, which is 23.1% and 45.4% higher than that of HCCNs and SCCNs in HA (10 ppm) system. The essential improvement can be ascribed to the synergetic effects from shell layer (size-exclusion) and core/shell (confinement effect). The degradation mechanism and pathway are further confirmed by radical quenching experiments and liquid chromatography-mass spectrograph (LC-MS), respectively. In addition, some influential factors, including reaction temperature, pH value, and peroxymonosulfate (PMS) dosage are investigated in detail. This work provides a possible way to selectively remove target contaminant from multiple pollutants in complex water system.


Assuntos
Poluentes Ambientais , Estruturas Metalorgânicas , Purificação da Água
15.
Environ Res ; 191: 110215, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32971079

RESUMO

Nanofiltration (NF) is an advanced environmental technology in water treatment. To thin film nanocomposite (TFN) membrane, good compatibility between nanofillers and polyamide (PA) layer is the guarantee of remarkable performance. Herein, tannic acid (TA) was employed as modifier of UIO-66-NH2 prior to the interfacial polymerization (IP). With TA modification, more interaction can be formed so that the compatibility between nanofillers and PA layer can be promoted at the molecular level. Characterizations demonstrated the coating of TA on UIO-66-NH2, together with successful introducing of nanofillers in TFN membranes. Compared to pristine thin film composite (TFC) membrane, both UIO-incorporated TFN (TFN-U) and TA modified UIO-incorporated TFN (TFN-TU) membranes showed higher permeance (111.2% and 93% enhancement, respectively). However, under the same nanofillers dose, TFN-TU exhibited slightly lower permeance and higher rejection than TFN-U since the bridging effect of TA healed non-selective voids in skin layer. With the increasing of nanofiller dose in IP, TFN-TU remained reasonable selectivity while TFN-U failed to. Moreover, TFN-TU showed better anti-fouling property due to TA modification. Introducing TA modified MOFs into IP can serve as an ingenious strategy for TFN membrane to achieve high-quality environmental applications.


Assuntos
Estruturas Metalorgânicas , Nanocompostos , Purificação da Água , Nylons , Taninos
16.
Nano Lett ; 19(8): 5423-5430, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31347853

RESUMO

Electrocatalytic denitrification is considered as the most promising technology to transform nitrates to nitrogen gas in sewage so far. Although noble metal-based catalysts as a cathode material have reached decent removal capacity of nitrate, the high cost is the main hamper of electrocatalytic reduction. Therefore, the development of alternative catalysis toward highly effective denitrification is imperative yet still remains a significant challenge. Herein, a corchorifolius-like structure, where Fe nanoparticles are sealed in carbon microspheres (CL-Fe@C) with a rough surface, has been elaborately designed by self-assemble strategy. Impressively, the architectured CL-Fe@C microspheres are surrounded with a lot of small iron nanoparticles and contain the high iron content of ∼74%. As a result, an excellent removal capacity of 1816 mg N/g Fe and a high nitrogen selectivity of 98% under a very low nitrate concentration of 100 mg/L are achieved when using the CL-Fe@C microspheres as electrocatalytic denitrification. The present work not only explores high performance electrocatalysis for the denitrification but also promote new inspiration for the preparation of other iron-based functional materials for diverse applications.

17.
J Environ Manage ; 255: 109842, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759203

RESUMO

The development of anaerobic digestion (AD) for volatile fatty acids (VFAs) production from waste activated sludge (WAS) is arrested due to low hydrolysis and acidification efficiency. This study proposed to enhance WAS reduction and VFAs accumulation during AD process via bioaugmentation of acetate-producing bacteria. Four acetogens were firstly isolated from a temperature-phased anaerobic digestion (TPAD) system. The acetate production efficiency of different isolates ranged from 15.8 to 73.7 mg acetate/g TOC, in which the bacterial strain NJUST19 was found to be the most effective strain. The results of morphological, biochemical characteristics as well as phylogenetic analysis showed that the isolate NJUST19 was Gram-positive and rod-shaped, catalase-negative, nitrate reduction-positive, methyl red-negative and capable of starch and gelatin hydrolysis, for which the name of Clostridium sp. NJUST19 was proposed. The optimal culture conditions (i.e. initial pH and temperature) were evaluated for their effects on microbe growth of selected NJUST19, and the maximum acetate production was observed at pH 9.0 and temperature of 40 °C. In the case of modified TPAD system inoculated with Clostridium sp. NJUST19, total suspended solids (TSS) removal rate and maximum VFAs accumulation increasing to 35.3% and 4200 mg/L, respectively, which was much higher than that of control (21.9% and 2894 mg/L). These results indicated that Clostridium sp. NJUST 19 is capable of enhancing digestion efficiency with a great benefit for VFAs production, offering potential prospects for bioaugmentation of WAS anaerobic digestion.


Assuntos
Ácidos Graxos Voláteis , Esgotos , Anaerobiose , Bactérias , Bactérias Anaeróbias , Reatores Biológicos , Filogenia
18.
IUBMB Life ; 71(11): 1760-1770, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31301220

RESUMO

Immune infiltration of tumors has been increasingly accepted as a prognostic factor in colon cancer. Here, we aim to develop a novel immune signature, based on estimated immune landscape from tumor transcriptomes, to predict the overall survival of patients with colon cancer. The compositions of 22 immune cell subtypes from three microarray datasets were characterized with the CIBERSORT deconvolution algorithm. A prognostic immunoscore (PIS) model for overall survival prediction was established by using least absolute shrinkage and selection operator (LASSO) penalized regression analysis. A total of 17 immune cell markers were screened out in the LASSO model and were then aggregated to generate the PIS. In the training cohort (n = 490), patients with high PIS exhibited a remarkably poorer overall survival than those with low PIS. Similar results were obtained in patients with different TNM stages and in patients receiving adjunctive chemotherapy or not. Multivariate Cox regression indicated that the PIS was an independent predictor for overall survival in colon cancer (hazard ratio: 2.734, 95% confidence interval: 2.052-3.643, p < .001). The prognostic capability of PIS was also confirmed in the testing cohort (n = 245) and the entire cohort (n = 735). As for biological implications, the PIS was significantly associated with some immune checkpoints, inflammatory factors, epithelial-mesenchymal transformation regulators, and many known signaling pathways in cancer. The results of our study provide a novel and promising immune signature for overall survival prediction of patients with colon cancer.


Assuntos
Algoritmos , Biomarcadores Tumorais/genética , Neoplasias do Colo/imunologia , Neoplasias do Colo/mortalidade , Transcriptoma , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Taxa de Sobrevida
19.
Analyst ; 144(2): 641-648, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30475352

RESUMO

Biomedical applications and biomarkers for early clinical diagnostics and the treatment of diseases demand efficient and selective enrichment platforms for glycoproteins. Thus, we herein report a facile and general approach for the preparation of boronic acid-functionalized magnetic nanoparticles for the selective enrichment of glycoproteins. More specifically, Fe3O4 magnetic nanoparticles were initially prepared via a solvothermal reaction, and core-shell-structured Fe3O4@SiO2 nanoparticles were obtained according to a sol-gel process. Subsequently, the Fe3O4@SiO2 surfaces were modified using 4-formylphenylboronic acid to allow the formation of strong yet reversible covalent bonds between boronic acid (BA) and the cis-1,2-diol groups of glycoproteins. The morphology and structure of the Fe3O4, Fe3O4@SiO2, and Fe3O4@SiO2-BA nanoparticles were characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometry, thereby confirming their successful preparation. The obtained BA-modified Fe3O4@SiO2 magnetic nanoparticles were applied in the attempted enrichment of two glycoproteins (ovalbumin (OVA) and transferrin (TRF)) and two non-glycoproteins (bovine serum albumin (BSA) and cytochrome c (Cyt C)). The results confirmed a significant difference in affinity between glycoproteins and non-glycoproteins. In addition, the recognition capability of the Fe3O4@SiO2-BA nanoparticles was demonstrated by the selective enrichment of glycoproteins from a complex system containing both glycoproteins (i.e., TRF) and non-glycoproteins (i.e., Cyt C).


Assuntos
Benzaldeídos/química , Ácidos Borônicos/química , Nanopartículas de Magnetita/química , Ovalbumina/química , Transferrina/química , Adsorção , Animais , Bovinos , Difusão Dinâmica da Luz , Óxido Ferroso-Férrico/química , Ovalbumina/isolamento & purificação , Soroalbumina Bovina/química , Soroalbumina Bovina/isolamento & purificação , Dióxido de Silício/química , Espectroscopia de Infravermelho com Transformada de Fourier , Transferrina/isolamento & purificação
20.
Environ Sci Technol ; 53(6): 3078-3086, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30801184

RESUMO

Forward osmosis (FO) can potentially treat textile wastewaters with less fouling than pressure-driven membrane processes such as reverse osmosis and nanofiltration. However, conventional FO membranes with asymmetric architecture experience severe flux decline caused by internal concentration polarization and fouling as dye molecules accumulate on the membrane surface. In this study, we present a new strategy for concentrating dye by using a self-standing, support-free FO membrane with a symmetric structure. The membrane was fabricated by a facile solution-casting approach based on a poly(triazole- co-oxadiazole- co-hydrazine) (PTAODH) skeleton. Due to its dense architecture, ultrasmooth surface, and high negative surface charge, the PTAODH membrane exhibits excellent FO performance with minimal fouling, low reverse salt flux, and negligible dye passage to the draw solution side. Cleaning with a 40% alcohol solution, after achieving a concentration factor of ∼10, resulted in high flux recovery ratio (98.7%) for the PTAODH membrane, whereas significant damage to the active layers of two commercial FO membranes was observed. Moreover, due to the existence of cytotoxic oxadiazole and triazole moieties in the polymer structure, our PTAODH membrane exhibited an outstanding antibacterial property with two model bacteria. Our results demonstrate the promising application of the symmetric PTAODH membrane for the concentration of textile wastewaters and its superior antifouling performance compared to state-of-the-art commercial FO membranes.


Assuntos
Águas Residuárias , Purificação da Água , Corantes , Membranas Artificiais , Osmose , Têxteis
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