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OBJECTIVE: The optimal choice for fusion strategy in Anterior Cervical Discectomy and Fusion (ACDF) remains an unresolved issue. This study aims to perform a network meta-analysis and systematic review of fusion rate and complication rate of various fusion strategies used in ACDF. METHODS: This study followed Prisma guidelines, and we searched PubMed, Embase, Cochrane Library, and Web of Science from inception to November 11, 2022, for Randomized Controlled trials comparing the efficacy and safety of fusion modalities in ACDF. The primary outcome was the fusion rate and complication rate. The PROSPERO number is CRD42022374440. RESULTS: This meta-analysis identified 26 Randomized Controlled trial studies with 1789 patients across 15 fusion methods. The cage with autograft + plating showed the highest fusion rate, surpassing other methods like iliac crest bone graft (ICBG) and artificial bone graft (AFG). The stand-alone cage with autograft (SATG) had the second highest fusion rate. Regarding complication rate, the cage with AFG (CAFG) had the highest rate, more than other methods. The ICBG had a higher complication rate compared to ICBG + P, AFG, stand-alone cage with artificial bone graft, SATG, and CALG. The SATG performed well in both fusion and complication rate. CONCLUSIONS: In this study, we conducted the first network meta-analysis to compare the efficacy and safety of various fusion methods in ACDF. Our findings suggest that SATG, with superior performance in fusion rate and complication rate, may be the optimal choice for ACDF. However, the results should be interpreted cautiously until additional research provides further evidence.
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Two new heteroleptic indium aminothiolate compounds [InClSC2H4N(Me)SC2H4]3[1] and [InSC2H4N(Me)SC2H4(C8H5F3NO)] [2] were synthesized by in situ salt metathesis reaction involving indium trichloride, aminothiol, and N,O-ß-heteroarylalkenol ligands. The complexes were subsequently purified and thoroughly characterized by nuclear magnetic resonance (NMR) analysis, elemental studies, mass spectroscopy, and X-ray diffraction single crystal analysis that showed a trigonal bipyramidal coordination of In(III) in both complexes. Thermogravimetric analysis of [1] revealed a multistep decomposition pathway and the formation of In2S3 at 350 °C, which differed from the pattern of [2] due to the lower thermal stability of [1]. Compound [2] exhibited a three-step decomposition process, resulting in the formation of In2S3 at 300 °C. The Chemical Vapor Deposition (CVD) experiment involving compound [2] was conducted on the FTO substrate, resulting in the production of singular-phase In2S3 deposits. A comprehensive characterization of these deposits, including crystal structure analysis via X-ray diffraction (XRD), and surface topography examination through scanning electron microscopy (SEM) has been completed. The presence of In-S units was also supported by the Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and energy dispersive spectroscopy (EDS) of the as-deposited films. Moreover, the electronic structure and thermal properties of compound [2] were investigated through DFT calculations. Electron density localization analysis revealed that the highest occupied molecular orbital (HOMO) exhibited dense concentration at the aminothiolate moiety of the complex, while the lowest unoccupied molecular orbital (LUMO) predominantly resided at the N,O-ß-heteroarylalkenolate ligand. Furthermore, our computational investigation has validated the formation of indium sulfide by elucidating an intermediate state, effectively identified through EI-MS analysis, as one of the plausible pathways for obtaining In2S3. This intermediate state comprises the aminothiolate ligand (LNS) coordinated with indium metal.
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DNA cross-links severely challenge replication and transcription in cells, promoting senescence and cell death. In this paper, we report a novel type of DNA interstrand cross-link (ICL) produced as a side product during the attempted repair of 1,N6-ethenoadenine (εA) by human α-ketoglutarate/Fe(II)-dependent enzyme ALKBH2. This stable/nonreversible ICL was characterized by denaturing polyacrylamide gel electrophoresis analysis and quantified by high-resolution LC-MS in well-matched and mismatched DNA duplexes, yielding 5.7% as the highest level for cross-link formation. The binary lesion is proposed to be generated through covalent bond formation between the epoxide intermediate of εA repair and the exocyclic N6-amino group of adenine or the N4-amino group of cytosine residues in the complementary strand under physiological conditions. The cross-links occur in diverse sequence contexts, and molecular dynamics simulations rationalize the context specificity of cross-link formation. In addition, the cross-link generated from attempted εA repair was detected in cells by highly sensitive LC-MS techniques, giving biological relevance to the cross-link adducts. Overall, a combination of biochemical, computational, and mass spectrometric methods was used to discover and characterize this new type of stable cross-link both in vitro and in human cells, thereby uniquely demonstrating the existence of a potentially harmful ICL during DNA repair by human ALKBH2.
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Adenina/análogos & derivados , Dioxigenasas , Ácidos Cetoglutáricos , Humanos , Dioxigenasas/metabolismo , ADN/química , Reparación del ADN , Compuestos Ferrosos , Aductos de ADN , Dioxigenasa Dependiente de Alfa-Cetoglutarato, Homólogo 2 de AlkB/metabolismoRESUMEN
Two fungal strains (K-2T and S1) were isolated from the deepest ocean sediment of the Challenger Deep located in the Mariana Trench. The internal transcribed spacer (ITS) gene sequences of the isolates K-2T and S1 differed from those of closely related species, such as Talaromyces assiutensis and T. trachyspermus. Phylogenetic analyses based on single and concatenated alignments of the genes, namely ITS, ß-tubulin (benA), calmodulin (cam), and the second-largest subunit fragment of the RNA polymerase II (rpb2) showed that the isolates K-2T and S1 were clustered together with other Talaromyces species, such as T. trachyspermus and T. assiutensis, as evidenced by the position on a terminal branch with high bootstrap support. They could also be distinguished from their closest relatives with valid published names via morphological and physiological characteristics, for example, growth at 4 °C-50 °C with a pH in the range of 1.5-12. Based on their phylogenetic, morphological, and physicochemical properties, the isolates K-2T and S1 represent a novel species in the genus Talaromyces, and the proposed name is Talaromyces sedimenticola sp. nov. The type strain is K-2T (= GDMCC 3.746T = JCM 39451T).
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Ácidos Grasos , Talaromyces , Ácidos Grasos/química , Análisis de Secuencia de ADN , Filogenia , ARN Ribosómico 16S/genética , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genéticaRESUMEN
Linkage chemistry and functional molecules derived from the stereogenic sulfur(VI) centre have important applications in organic synthesis, bioconjugation, drug discovery, agrochemicals and polymeric materials. However, existing approaches for the preparation of optically active S(VI)-centred compounds heavily rely on synthetic chiral S(IV) pools, and the reported linkers of S(VI) lack stereocontrol. A modular assembly method, involving sequential ligand exchange at the S(VI) centre with precise control of enantioselectivity, is appealing but remains elusive. Here we report an asymmetric three-dimensional sulfur(VI) fluoride exchange (3D-SuFEx) reaction based on thionyl tetrafluoride gas (SOF4). A key step involves the chiral ligand-induced enantioselective defluorinative substitution of iminosulfur oxydifluorides using organolithium reagents. The resulting optically active sulfonimidoyl fluorides allow for further stereospecific fluoride-exchange by various nucleophiles, thereby establishing a modular platform for the asymmetric SuFEx ligation and the divergent synthesis of optically active S(VI) functional molecules.
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Developing wearable supercapacitors (SCs) with high stretchability, arbitrary deformability, and antifreezing ability is still a challenge. In the present work, an ultrahigh-ionic-conductivity, antifreezing poly(amidoxime)-graft-polyzwitterion (PAO-g-PSBMA) hydrogel electrolyte is fabricated by grafting PSBMA in PAO. Owing to the abundant hydrophilic and high ionic adsorption capacity of amidoxime groups in PAO and zwitterion groups in PSBMA, the as-prepared PAO-g-PSBMA hydrogel can facilitate the dissociation of lithium salt and exhibit an ultrahigh ionic conductivity of 29.8 S m-1 at 25 °C and 3.4 S m-1 even at -30 °C. Employing mATi3C2Tx and mSTi3C2Tx, which contain small amounts of PAO-AGE and PAO-g-PSBMA dispersions, respectively, coated onto both sides of the PAO-g-PSBMA hydrogel, we followed a thermal treatment to facilely form integrated stretchable flexible SCs. The as-prepared SCs show an outstanding recoverable tensile stain of 80% and an excellent electrochemical stability under many types and times of arbitrary deformation. More importantly, as-prepared mATi3C2Tx- and mSTi3C2Tx-based SCs present fantastic antifreezing ability and excellent stability with 74.6 and 78.3% retention of the initial capacitance, respectively, even after 1000 times of stretching to 60% at -30 °C. This work offers a new strategy of using PAO-grafted polyzwitterion for obtaining an antifreezing stretchable SC, which shows a high potential for application in next-generation integrated stretchable devices in various fields.
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Metal nanoparticles (NP) supported on TiO2 are known to be efficient photocatalysts for solar-to-chemical energy conversion. While TiO2 decorated with copper NPs has the potential to become an attractive system, the poor oxidative stability of Cu severely limits its applicability. In this work, we demonstrate that, when Cu NPs supported on TiO2 nanobelts (NBs) are engaged in the photocatalytic generation of H2 from water under light illumination, Cu is not only oxidized in CuO but also dissolved under the form of Cu+/Cu2+ ions, leading to a continuous reconstruction of nanoparticles via Ostwald ripening. By nanoencapsulating the CuOx (Cu/CuO/Cu2O) NPs by a few layers of carbon supported on TiO2 (TC@C), Ostwald ripening can be suppressed. Simultaneously, the resulting CuOx@C NPs are photoreduced under light illumination to generate Cu@C NPs. This photoswitching strategy allows the preparation of a Cu plasmonic photocatalyst with enhanced activity for H2 production. Remarkably, the photocatalyst is even active when illuminated with visible light, indicating a clear plasmonic enhancement of photocatalytic activity from the surface plasmonic resonance (SPR) effect of Cu NPs. Three-dimensional electromagnetic wave-frequency domain (3D-EWFD) simulations were conducted to confirm the SPR enhancement. This advance bodes for the development of scalable multifunctional Cu-based plasmonic photocatalysts for solar energy transfer.
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Nucleic acid methylations are important genetic and epigenetic biomarkers. The formation and removal of these markers is related to either methylation or demethylation. In this review, we focus on the demethylation or oxidative modification that is mediated by the 2-oxoglutarate (2-OG)/Fe(II)-dependent AlkB/TET family enzymes. In the catalytic process, most enzymes oxidize 2-OG to succinate, in the meantime oxidizing methyl to hydroxymethyl, leaving formaldehyde and generating demethylated base. The AlkB enzyme from Escherichia coli has nine human homologs (ALKBH1-8 and FTO) and the TET family includes three members, TET1 to 3. Among them, some enzymes have been carefully studied, but for certain enzymes, few studies have been carried out. This review focuses on the kinetic properties of those 2-OG/Fe(II)-dependent enzymes and their alkyl substrates. We also provide some discussions on the future directions of this field.
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OBJECTIVE: To observe the expression of helper T cells 17(Th17), interleukin 23 (IL-23) in peripheral blood in patients with acute myeloid leukemia (AML), to analyze the relationship between Th17, IL-23 in peripheral blood and immunophenotype. METHODS: 105 patients with AML in the hospital from January 2019 to January 2021 were prospectively selected as the research subjects, the expression of Th17 and IL-23 in peripheral blood of patients with AML was detected by flow cytometry; immunophenotype was detected and counted. The relationship between the expression of Th17, IL-23 in peripheral blood and immunophenotype of AML patients was analyzed. Draw ROC curve and analyze the predictive value of Th17 and IL-23 expression in peripheral blood to immunophenotype. RESULTS: The immunophenotype results of AML patients showed that myeloid antigen, lymphoid antigen and hematopoietic stem/progenitor cell marker antigen were positive expressed for various antigens in 105 AML patients, in myeloid antigens, CD13+ accounted for the highest proportion (93.33%), in lymphoid antigens, CD56+ accounted for the highest proportion (32.38%), and in hematopoietic stem/progenitor cell marker antigens, CD38+ accounted for the highest proportion (68.57%). The expression of Th17 in peripheral blood of AML patients with CD56+, CD7+, CD34+ and human leukocyte antigen DR+(HLA-DR+) were higher than that of AML patients with CD56-, CD7-, CD34-, HLA-DR-, the expression of IL-23 in peripheral blood of AML patients with CD56+, CD34+ and HLA-DR+ were higher than that of AML patients with CD56-, CD34-, HLA-DR-, the differences were statistically significant (P<0.05); compared the expression of Th17 and IL-23 in peripheral blood between other antibody positive and negative patients, there was no statistical significant difference (P>0.05). Logistic regression analysis showed that the high expression of Th17 in patients with AML was related to the positive expression of CD56, CD7, CD34 and HLA-DR in the detection of immunophenotype, the high expression of IL-23 was related to the positive expression of CD56, CD34 and HLA-DR in the detection of immunophenotype. The ROC curve showed that the AUC of expression levels of Th17 and IL-23 in peripheral blood alone and in combination for predicting CD56+, CD34+, HLA-DR+ and Th17 in peripheral blood for predicting CD7+ were mostly 0.5-0.7, which had certain predictive value, but the predictive performance was low. CONCLUSION: Myeloid antigen, lymphoid antigen and hematopoietic hematopoietic stem/progenitor cell marker antigen are positive expressed for various antigens in AML patients, the high expression of Th17 in peripheral blood of AML patients is related to the positive expression of CD56, CD7, CD34 and HLA-DR in detection of immunophenotyping, the high expression of IL-23 is related to the positive expression of CD56, CD34 and HLA-DR in the detection of immunophenotype.
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Subunidad p19 de la Interleucina-23/sangre , Interleucina-23 , Leucemia Mieloide Aguda , Antígenos CD34 , Citometría de Flujo/métodos , Antígenos HLA-DR/análisis , Humanos , Inmunofenotipificación , Leucemia Mieloide Aguda/genética , Células Th17RESUMEN
The development of a novel preparation strategy for 3D porous network structures with an aligned channel or wall is always in challenge. Herein, a 3D porous network composed of an aligned graphene-based wall is fabricated by a confined self-assembly strategy in which holey reduced graphene oxide (HrGO)/lignin sulfonate (Lig) composites are orientedly anchored on the framework of the Lig/single-wall carbon nanotube (Lig/SWCNT) hydrogel by vacuum-assisted filtration accompanied with confined self-assembly and followed with hydrothermal treatment. After freeze drying, the obtained ultralight Lig/SWCNT/HrGOal aerogel exhibits excellent shape memory properties and can roll back to the original shape even if suffering from a high compressive strain of 86.2%. Furthermore, the as-prepared aerogel used as a water-driven artificial muscle shows powerful driving force and can lift ultrahigh weight cargo that is 1030.6 times its own weight. When the prepared Lig/SWCNT/HrGOal aerogel is used as a pressure sensor, it also exhibits high sensitivity (2.28 kPa-1) and a wide detection region of 0.27-14.1 kPa. Additionally, the symmetric flexible supercapacitor assembled with as-prepared aerogel films shows superior stored energy performance that can tolerate 5000 cycles of bending. The present work not only fabricates a high-performance multifunctional material but also develops a new strategy for the preparation a wood-like 3D porous aligned wall network structure.
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The preparation of graphene-based aerogels with excellent mechanical strength, elasticity, and compressibility is still a challenge. Herein, we demonstrate a robust, elastic, and lightweight graphene/aramid nanofiber/polyaniline nanotube (rGO/ANF/PANIT) aerogel that is prepared by mixing graphene oxide (GO), ANF, and PANIT dispersions, followed by thermal treatment at 90 °C, freeze-drying, and a low-temperature annealing process. The PANIT bonds the graphene sheets tightly, benefitting the formation of composite gels. The ANF tightly interconnects the graphene sheets and further reinforces the composite network framework significantly, hence endowing rGO/ANF/PANIT composite aerogels with robust mechanical property. The prepared aerogels present a low density of â¼12 mg cm-3, high conductivity, good resilience, and high compressibility. The rGO/ANF/PANIT aerogels as pressure sensors exhibit a high sensitivity of 1.73 kPa-1, low detection limit (40 Pa), wide detection range, and excellent compressive cycle stability, highlighting the promising applications in pressure-sensitive electrical devices, including medical health detection, wearable electronics, and intelligent packaging fields.
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BACKGROUND: The study looks at a changed in consumer's eating and purchasing habits during COVID-19 period. There are several modes of transmission but transmission through food as being speculated is one area that has not been confirmed through research. The study, therefore, looks at how speculations about COVID-19 spreading through food has affected consumers' eating and purchasing habits. This study through probit model analysed how consumers' eating and purchasing habits have been influenced. RESULTS: The result shows that age, gender and education have negatively influenced consumer's eating and purchasing habits during the COVID-19 pandemic compared to pre-pandemic period. The preference for imported food items, preference for frozen food, been infected or knowing someone who has been infected by the virus, and been infected through agricultural source or knowing someone who has been infected by the COVID-19 through agricultural source have negatively affected consumers' eating and purchasing habits compared to pre-pandemic period. The result, however, suggests that consumers who trust in the cold-chain food systems ability to limit the spread of the COVID-19 still maintain a positive eating and purchasing habits. CONCLUSIONS: The study provides evidence on the impact of COVID-19 on consumer's eating and purchasing habits. Therefore, there is the need to institute proper sanitary measures, especially at cold-chain food systems to help curb the spread and also boost consumers' confidence.
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Dodecyl tannin derivative linked with 1,2,3-triazole was prepared by the click reaction of dodecyl azide and alkynylated tannin. The structure of tannin derivative was identified by FT-IR spectrometer and elemental analyzer, and the surface activity, antioxidant activity and antimicrobial activity of tannin derivative were studied. The surface tension of tannin derivative was significantly reduced because of the introduction of long chain alkyl groups, and the lowest surface tension was 38.87â mN/m at 1.0â mg/mL. The tannin derivative had strong ability to scavenge 1,1-diphenyl-2-picrylhydrazyl radical, the scavenging rate could reach 89.08 % at 0.25â mg/mL. The tannin derivative exhibited strong antibacterial activity against E.â coli and S.â aureus due to the increased fat-solubility of tannin derivative and the introduction of antibacterial triazole groups in molecular structure of tannin derivative, and the bacteriostatic ratios of tannin derivative against E.â coli and S.â aureus were 92.16 % and 89.21 % at 2.0â mg/mL, respectively. The tannin derivative can be used as good candidates for antibacterial packaging or antioxidant supplements.
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Antibacterianos/química , Antioxidantes/química , Taninos/química , Triazoles/química , Alquilación , Antibacterianos/síntesis química , Antibacterianos/farmacología , Química Clic , Escherichia coli/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacosRESUMEN
Herein, we describe a photoredox three-component atom-transfer radical addition (ATRA) reaction of aryl alkynes directly with dialkyl disulfides and alkylsulfinates, circumventing the utilization of chemically unstable and synthetically challenging S-alkyl alkylthiosulfonates as viable addition partners. A vast array of (E)-ß-alkylsulfonylvinyl alkylsulfides was prepared with great regio- and stereoselectivity. Moreover, this powerful tactic could be employed to tag cysteine residues of complex polypeptides in solution or on resin merging with solid phase peptide synthesis (SPPS) techniques. A sulfonyl-derived redox responsive fluorescent probe could be conveniently introduced on the peptide, which displays green fluorescence in cells while showing blue fluorescence in medium. The photophysical investigations reveal that the red shift of the emission fluorescence is attested to reduction of carbonyl group to the corresponding hydroxyl moiety. Interestingly, the fluorescence change of tagged peptide could be reverted in cells by treatment of H2O2, arising from the reoxidation of hydroxyl group back to ketone by the elevated level of reactive oxygen species (ROS).
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To endow high mechanical strength and thermal stability aramid nanofibers (ANF) with novel functionality will lead to great applications. Herein, a strategy to generate covalent bonds among components towards obtaining uniform ANF/reduced holey graphene oxide (ANF/rHGO) and ANF/rHGO/polyaniline (ANF/rHGO/PANI) hydrogels with high mechanical properties is proposed through solvent exchange gelation and subsequent hydrothermal treatment. The as-prepared ANF/rHGO and ANF/rHGO/PANI hydrogels demonstrate excellent recoverability at high compressive strength of 20.2 and 13.8 kPa with a strain of 34.4% and 30.6%, respectively, compared to a recoverability of 92.5% at a strain of â¼20% for ANF hydrogels. Moreover, ANF/rHGO and ANF/rHGO/PANI aerogels possess fast and high oil absorption capacity of 38.9-64.1 g g-1 and 24.5-44.0 g g-1, respectively. ANF/rHGO and ANF/rHGO/PANI films obtained after vacuum-drying exhibit a high tensile strength of 121.4 and 95.5 MPa, respectively. Additionally, ANF/rHGO/PANI thin films present good selective absorption of visible light by controlling the doping level of PANI. ANF/rHGO/PANI aerogel films prepared by freeze-drying are assembled into flexible solid-state symmetric supercapacitors and deliver a favorable specific capacitance of 200 F g-1, a desirable capacitance retention of 98.9% after 2500 mechanical bending cycles and an approximately 100% capacitance retention even after keeping tensile force for 15 h. The as-prepared hydrogels, aerogels and derived films with such excellent performances are promising for applications in oil pollution removal, optical filters and flexible load-bearing energy storage devices.
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RATIONALE: Chronic myelogenous leukemia (CML) with thrombocytosis and complex chromosomal translocation is extremely rare in clinical setting. Here, we reported the clinical and pathological characteristics of CML patients, which were characterized by thrombocytosis and complex Philadelphia chromosome translocation. Moreover, we also introduced our therapeutic schedule for this patient as well as review relative literature. PATIENT CONCERNS: A 24-year-old female presented with night sweating, fatigue, and intermittent fever for 1âmonth. DIAGNOSIS: Fluorescence in situ hybridization results revealed that breakpoint cluster region (BCR)-Abelson (ABL) gene fusion in 62% of the cells and karyotyping showed a complex 3-way 46, XY, t(9;22;11) (q34;q11;q13) [19/20] translocation. This patient was diagnosed with CML complicated with thrombocytosis and complex Philadelphia chromosome translocation. INTERVENTIONS: The patients received continuously oral imatinib mesylate tablets (400âmg) once a day. OUTCOMES: After treatment with imatinib for 3âmonths, the BCR/ABLIS was less than 0.1% and achieved major molecular response. Moreover, the BCR/ABLIS of this patient achieved major molecular response. The BCR/ABLIS values at 6âmonths and 12âmonths were less than 0.01% and 0.0032%, respectively. And no BCR/ABL fusion was detected in the next 2âyears follow-up period. LESSONS: Imatinib might represent a preferred therapeutic option for CML patients with rare thrombocytosis and complex chromosomal translocation. In addition, BCR/ABL fusion gene examination in patients with thrombocytosis might represent an effective strategy to avoid the misdiagnosis of this specific CML population.
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Antineoplásicos/uso terapéutico , Mesilato de Imatinib/uso terapéutico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Cromosoma Filadelfia , Trombocitosis/etiología , Femenino , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/sangre , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Adulto JovenRESUMEN
Photoelectrochemical (PEC) hydrogen evolution has been acknowledged as a promising "green" technique to convert solar energy into clean chemical fuel. Photoanodes play a key role in determining the performance of PEC systems, spurring numerous efforts to develop advanced materials as well as structures to improve the photoconversion efficiency. In this work, we report the rational design of a plasmonic hierarchical nanorod array, composed of oriented one-dimensional (1D) CdS nanorods decorated with a uniformly wrapped graphite-like carbon (CPDA) layer and Au nanoparticles (Au NPs), as highly efficient photoanode materials. An interfacial in situ reduction-graphitization method has been conducted to prepare the CdS/CPDA/Au nanoarchitecture, where polydopamine (PDA) coating was used as a C source and a reductant. The CdS/CPDA/Au nanoarray photoanode demonstrates superior photoconversion efficiency with a photocurrent density of 8.74 mA/cm2 and an IPCE value (480 nm) of 30.2% (at 1.23 V vs RHE), under simulated sunlight irradiation, which are 12.7 and 13.5 times higher than pristine CdS. The significant enhancement of PEC performance is mainly benefited from the increase of the entire quantum yield and efficiency due to the formation of a Schottky rectifier, localized surface plasmon resonance (LSPR)-enhanced light absorption, and promoted hot-electron injection from interlayered graphene-like carbon. More importantly, thanks to the inhibited charge carrier recombination process and transferred oxidation reaction sites, the fabricated CdS/CPDA/Au photoelectrode exhibits lengthened electron lifetimes and better photostability, illustrating its wonderful potential for future PEC application.
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Two dimensional MXenes with fascinating characteristics of high electrical conductivity, high density and electroactivity show promising applications in various fields. However, the direct applications of MXenes have been limited due to their inferior mechanical properties and easy restacking. Herein, a kind of nacre-like composite film constructed with Ti3C2Tx, cellulose nanofiber (HCNF) and sodium lignosulfonate (Lig) obtained through the hydrothermal process, named Ti3C2Tx/HCNF@Lig, has been successfully synthesized. The hydrothermal cellulose nanofiber (HCNF) film shows an enhanced mechanical strength (114 MPa) compared to that of the CNF film (95 MPa). Wood-inspired HCNF@Lig composite films present an enhanced mechanical tensile strength of up to 133 MPa. Nacre-like deformable Ti3C2Tx/HCNF@Lig(3@1) composite films exhibit high conductivity (up to 1.75 × 105 S m-1) and mechanical properties (up to 258 MPa). The electrodes of Ti3C2Tx/HCNF@Lig(3@1)97/3 composite film assembled flexible solid-state supercapacitors possess an excellent volumetric specific capacitance of 748.96 F cm-3. The corresponding deformable supercapacitors show an excellent energy density of 16.2 W h L-1 and outstanding electrochemical cycling stability. The as-prepared nacre-like Ti3C2Tx/HCNF@Lig composite films with high mechanical properties and electrochemical performance are expected to be practically applied in flexible/wearable energy storage devices.
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A synergetic copper/photoredox catalyzed ATRA of styrenes and thiosulfonates is developed. Besides aryl ethylenes, the challenging α-substituted styrenes were employed to construct the benzylic quaternary carbon centers. Owing to the mild conditions as well as the high level of substrate compability, this ATRA could be applied to derivatize bioactive natural products in late stage, and to install fluorophores across alkenes. The mechanistic studies reveal sulfonyl radicals as the key intermediate in the transformation.
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Flexible all-solid-state supercapacitors (ASSSs) are excellent energy storage devices for portable/wearable electronics, although the development of an excellent comprehensive performance film electrode for the extraordinary flexible ASSSs still faces a great challenge. Here, bendable, foldable and anti-exfoliative Ti3C2Tx MXene-based films utilized as supercapacitor electrodes are reported. Polyaniline/Ti3C2Tx composites (i-PANI@Ti3C2Tx) were prepared by in situ oxidant-free polymerization of aniline on Ti3C2Tx nanosheets with p-phenylenediamine (PPD) as an initiator. Lignosulfonate (Lig) and Ti3C2Tx were constructed into a compact composite (Lig@Ti3C2Tx) film based on the hydrogen bonds formed between Lig and Ti3C2Tx. The Lig@Ti3C2Tx/i-PANI@Ti3C2Tx(5/5) hybrid film was produced by vacuum-assisted filtration of the mixed two composite dispersions. The as-prepared films can be arbitrarily deformed (such as bending and folding). They show high tensile strength and vertical-plane (the plane of film) tensile strength with 33.2 and 0.28 MPa for the i-PANI@Ti3C2Tx film, 75.4 and 0.77 MPa for the Lig@Ti3C2Tx film, and 53.7 and 0.58 MPa for the Lig@Ti3C2Tx/i-PANI@Ti3C2Tx(5/5) film (those of Ti3C2Tx film are 17.4 and 0.21 MPa), respectively. The enhanced vertical-plane tensile strength of the as-prepared composite films indicates that the large binding force generated between the Ti3C2Tx nanosheets can effectively prevent the exfoliation of films. The electrodes of the as-prepared i-PANI@Ti3C2Tx, Lig@Ti3C2Tx and Lig@Ti3C2Tx/i-PANI@Ti3C2Tx(5/5) films assembled into symmetric flexible ASSSs can deliver excellent specific capacitances of 310 F g-1 (â¼1001 F cm-3), 271 F g-1 (â¼881 F cm-3) and 295 F g-1 (â¼959 F cm-3), respectively. In addition, the corresponding supercapacitors exhibit ultrahigh energy densities of 34.8, 30.6 and 33.3 W h L-1, respectively. It is expected that the as-prepared MXene-based films can be applied in various fields, such as electromagnetic-interference shielding and batteries. Furthermore, the as-prepared flexible ASSSs can be practically used as a wearable energy storage device.