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Tn antigen (CD175), recognized as the precursor monosaccharide (α-GalNAc) of mucin O-glycan, is a well-known tumor-associated carbohydrate antigen (TACA). It has emerged as a potential biomarker for cancer diagnosis and prognosis. However, the role it plays in cancer biology remains elusive due to the absence of a sensitive and selective detection method. In this study, we synthesized two new probes based on a unique uridine-5'-diphospho-α-d-galactose (UDP-Gal) derivative, each functionalized with either a fluorescence or a cleavable biotin tag, to develop an innovative one-step enzymatic labeling strategy, enabling the visualization, enrichment, and site-specific mapping of the Tn antigen with unparalleled sensitivity and specificity. Our versatile strategy has been successfully applied to detect and image Tn antigen across various samples, including the complex cell lysates, live cells, serum, and tissue samples. Compared to the traditional lectin method, this one-step enzymatic method is simpler and more efficient (>10/100-fold in sensitivity). Furthermore, it allowed us to map 454 Tn-glycoproteins and 624 Tn-glycosylation sites from HEK293FTn+ and Jurkat cells. Therefore, our strategy provides an exceptionally promising tool for revealing the biological functions of the Tn antigen and advancing cancer diagnostics.
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Antígenos Glicosídicos Associados a Tumores , Antígenos Glicosídicos Associados a Tumores/química , Antígenos Glicosídicos Associados a Tumores/análise , Humanos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese químicaRESUMO
Cost-effective and earth-abundant oxygen evolution reaction (OER) electrocatalysts are an incredible research hotspot in numerous energy storage and conversion technology fields. Herein, CoS2/MoS2 nanosheets supported by carbon cloth as a dual-active CC@CoS2/MoS2 heterostructure electrocatalyst is prepared through a simple solvothermal method. The catalyst demonstrates admirable OER performance in 1 M KOH solution with a low overpotential of 243 mV at a current density of 10 mA cm-2 and a minor Tafel slope of 109 mV dec-1, displaying honorable stability after 1000 cyclic voltammetry (CV) cycles and long-term robustness over 60 h. Theoretical calculations further ascertain that the rate-determining step of the electrocatalytic course of the CC@CoS2/MoS2 heterostructure is the conversion *O + OH- â *OOH + e- with a lower energy barrier of 1.49 eV due to the heterojunction established by CoS2 and MoS2, which can promote the OER performance of electrocatalysts. The actual identification of the catalytic mechanism in the heterostructure is conducive to the improvement of electrocatalysis applications in the OER.
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Auxin plays a crucial role in regulating root growth and development, and its distribution pattern under environmental stimuli significantly influences root plasticity. Under K deficiency, the interaction between K+ transporters and auxin can modulate root development. This study compared the differences in root morphology and physiological mechanisms of the low-K-tolerant maize inbred line 90-21-3 and K-sensitive maize inbred line D937 under K-deficiency (K+ = 0.2 mM) with exogenous NAA (1-naphthaleneacetic acid, NAA = 0.01 mM) treatment. Root systems of 90-21-3 exhibited higher K+ absorption efficiency. Conversely, D937 seedling roots demonstrated greater plasticity and higher K+ content. In-depth analysis through transcriptomics and metabolomics revealed that 90-21-3 and D937 seedling roots showed differential responses to exogenous NAA under K-deficiency. In 90-21-3, upregulation of the expression of K+ absorption and transport-related proteins (proton-exporting ATPase and potassium transporter) and the enrichment of antioxidant-related functional genes were observed. In D937, exogenous NAA promoted the responses of genes related to intercellular ethylene and cation transport to K-deficiency. Differential metabolite enrichment analysis primarily revealed significant enrichment in flavonoid biosynthesis, tryptophan metabolism, and hormone signaling pathways. Integrated transcriptomic and metabolomic analyses revealed that phenylpropanoid biosynthesis is a crucial pathway, with core genes (related to peroxidase enzyme) and core metabolites upregulated in 90-21-3. The findings suggest that under K-deficiency, exogenous NAA induces substantial changes in maize roots, with the phenylpropanoid biosynthesis pathway playing a crucial role in the maize root's response to exogenous NAA regulation under K-deficiency.
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Deficiência de Potássio , Plântula , Plântula/genética , Plântula/metabolismo , Zea mays/metabolismo , Deficiência de Potássio/metabolismo , Transcriptoma , Perfilação da Expressão Gênica , Ácidos Indolacéticos/farmacologia , Ácidos Indolacéticos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de PlantasRESUMO
The extensive use of herbicides has raised concerns about crop damage, necessitating the development of effective herbicide safeners. Fluxofenim has emerged as a promising herbicide safener; however, it's underlying mechanism remains unclear. Here, we screened two inbred lines 407B and HYZ to investigate the detoxication of fluxofenim in mitigating metolachlor damage in sorghum. Metolachlor inhibited seedling growth in both 407B and HYZ, while, fluxofenim could significantly restore the growth of 407B, but not effectively complement the growth of HYZ. Fluxofenim significantly increased the activities of glutathione-S-transferase (GST) to decrease metolachlor residue in 407B, but not in HYZ. This implys that fluxofenim may reduce metolachlor toxicity by regulating its metabolism. Furthermore, metolachlor suppressed AUX-related and JA-related genes expression, while up-regulated the expression of SA-related genes. Fluxofenim also restored the expression of AUX-related and JA-related genes inhibited by metolachlor and further increased expression of SA-related genes. Moreover, we noted a significant increase in the content of trans-zeatin O-glucoside (tZOG) and Gibberellin1 (GA1) after the fluxofenim treatment. In conclusion, fluxofenim may reduce the injury of herbicide by affecting herbicide metabolism and regulating hormone signaling pathway.
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Herbicidas , Sorghum , Herbicidas/toxicidade , Herbicidas/metabolismo , Sorghum/genética , Transcriptoma , Glutationa Transferase/metabolismo , Grão ComestívelRESUMO
OBJECTIVE: To evaluate the clinical effectiveness of vacuum sealing drainage (VSD) in the treatment of severe scrotal infectious diseases and to summarize the practical experience obtained during its implementation. METHODS: Clinical data from 9 patients with severe scrotal infectious diseases were compiled. All patients underwent debridement assisted by a VSD device in addition to conventional treatment measures. RESULTS: Following debridement with VSD device, combined with systemic anti-infection treatment and nutritional support, all patients exhibited favorable therapeutic outcomes, with no fatalities. The average duration of debridement was 81±27 minutes. One patient necessitated secondary debridement and skin grafting, while another was transferred to the ICU due to septic shock. CONCLUSIONS: The application of VSD device can streamline the treatment process for severe scrotal infectious diseases, alleviate patient discomfort, and promote patient recovery.
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Doenças Transmissíveis , Doenças dos Genitais Masculinos , Tratamento de Ferimentos com Pressão Negativa , Humanos , Masculino , Adjuvantes Imunológicos , Drenagem , Doenças dos Genitais Masculinos/cirurgiaRESUMO
OBJECTIVE: To evaluate the efficacy and safety of cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors combined with endocrine therapy (ET) for hormone receptor-positive (HR+)/human epidermal growth factor receptor 2-negative (HER-2-) advanced breast cancer (ABC) patients. METHODS: We searched clinical trials of CDK4/6 inhibitors combined with ET and calculated the clinical outcomes. RESULTS: HR+/HER-2- ABC patients treated with CDK4/6 inhibitors combined with ET had significantly prolonged progression-free survival (PFS) and improved objective response rate (ORR) and clinical benefit rate (CBR). CONCLUSIONS: CDK4/6 inhibitors combined with ET can bring more clinical benefits to ABC patients, and the safety profile is acceptable.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Receptores de Estrogênio/uso terapêutico , Receptores de Progesterona/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Feminino , HumanosRESUMO
This study aims to investigate the mechanisms through which fructose diphosphate (FDP) causes anti-hypoxia and anti-fatigue effects and improves learning and memory. Mice were divided into three groups: low-dose FDP (FDP-L), high-dose FDP (FDP-H), and a control group. Acute toxic hypoxia induced by carbon monoxide, sodium nitrite, and potassium cyanide and acute cerebral ischemic hypoxia were used to investigate the anti-hypoxia ability of FDP. The tests of rod-rotating, mouse tail suspension, and swimming endurance were used to explore the anti-fatigue effects of FDP. The Morris water maze experiment was used to determine the impact of FDP on learning and memory ability. Poisoning-induced hypoxic tests showed that mouse survival time was significantly prolonged in the FDP-L and FDP-H groups compared with the control group (p < 0.05). In the exhaustive swimming test, FDP significantly shortened struggling time and prolonged the time of mass-loaded swimming; the rod-rotating test showed that endurance time was significantly prolonged by using FDP (p < 0.05). FDP significantly decreased lactate and urea nitrogen levels and increased hepatic and muscle glycogen and glucose transporter-4 and Na+-K+-ATPase (p < 0.05). To conclude, FDP enhances hypoxia tolerance and fatigue resistance and improves learning and memory ability through regulating glucose and energy metabolism.
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Comportamento Animal/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fadiga/prevenção & controle , Frutosedifosfatos/farmacologia , Hipóxia-Isquemia Encefálica/prevenção & controle , Hipóxia/prevenção & controle , Aprendizagem/efeitos dos fármacos , Memória/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Fadiga/metabolismo , Fadiga/fisiopatologia , Fadiga/psicologia , Hipóxia/metabolismo , Hipóxia/fisiopatologia , Hipóxia/psicologia , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/fisiopatologia , Hipóxia-Isquemia Encefálica/psicologia , Locomoção/efeitos dos fármacos , Camundongos , Teste do Labirinto Aquático de Morris/efeitos dos fármacos , Teste de Desempenho do Rota-Rod , NataçãoRESUMO
BACKGROUND: Atrazine is widely used in agriculture and is a known endocrine disrupting chemical. Atrazine can seep into the water body through surface, posing a potential threat to the aquatic ecological environment and human drinking water source. In vertebrate, studies have shown that it can affect reproduction and development seriously, but its molecular mechanism for aquatic animals is unknown. Aquaculture is very common in China, especially common carp, whose females grow faster than males. However, the effects of atrazine on the reproduction of carp, especially miRNA, have not been investigated. RESULTS: In this study, common carp (Cyprinus carpio) at two key developmental stages were exposed to atrazine in vitro. Sex ratio was observed to analyze the effect of atrazine on the sex. MiRNA expression profiles were analysed to identify miRNAs related to gonad development and to reveal the atrazine mechanisms interfering with gonad differentiation. The results showed that the sex ratio was biased towards females. Atrazine exposure caused significant alteration of multiple miRNAs. Predicted targets of differently-expressed miRNAs were involved in many reproductive biology signalling pathways. CONCLUSIONS: Our results indicate that atrazine promoted the expression of female-biased genes by decreasing miRNAs in primordial gonad. In addition, our results indicate that atrazine can up-regulate aromatase expression through miRNAs, which supports the hypothesis that atrazine has endocrine-disrupting activity by altering the gene expression profile of the Hypothalamus-Pituitary-Gonad axis through its corresponding miRNAs.
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Atrazina/toxicidade , Carpas/genética , Disruptores Endócrinos/toxicidade , Gônadas/efeitos dos fármacos , MicroRNAs/genética , Diferenciação Sexual/efeitos dos fármacos , Animais , Aromatase/genética , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Gônadas/embriologia , Masculino , Razão de Masculinidade , Transcriptoma/efeitos dos fármacosRESUMO
Fresh tea leaves were crushed into juice and then fermented (oxidation) to obtain fermented black tea juice, which can be used to prepare black tea beverage. The effects of addition of oolong tea infusion or tossing of tea leaves on the sensory quality and theaflavins (TFs) concentration of fermented black tea juice were investigated. The results showed that both addition of tea infusion and tossing of fresh tea leaves increased the TFs/thearubigins (TRs) ratio and improved the sensory quality of fermented black tea juice. The TFs/TRs ratio was found to be significantly correlated with the scores for flavor (r = 0.98), mouth feel (r = 0.94), and overall acceptability (r = 0.91) of the fermented black tea juices from different processes. This result suggested that a relatively high concentration of catechins and stepwise enzymatic oxidation were the crucial factors that increased the TFs/TRs ratio and improved the sensory quality. The combination of adding tea infusion and tossing fresh tea leaves greatly improved the quality of the fermented black tea juice by markedly increasing the TFs/TRs ratio (87%). Results of the present study provided useful information for improving the quality of fermented black tea juice.
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Penicillin-binding protein 3 (PBP3) of Pseudomonas aeruginosa is the primary target of ß-lactams used to treat pseudomonas infections. Meanwhile, structure change and overproduction of PBP3 play important roles in the drug resistance of P. aeruginosa. Therefore, studies on the gene and structure of PBP3 are urgently needed. P. aeruginosa CMCC 10104 is a type culture strain common used in China. However, there is no report on its genomic and proteomic profiles. In this study, based on ftsI of P. aeruginosa PAO1, the gene encoding PBP3 was cloned from CMCC 10104. A truncated version of the ftsI gene, omitting the bases encoding the hydrophobic leader peptide (amino acids 1-34), was amplified by PCR. The cloned DNA shared 99.76% identity with ftsI from PAO1. Only four bases were different (66 C-A, 1020 T-C, 1233 T-C, and 1527 T-C). However, there were no differences between their deduced amino acid sequences. The recombinant PBP3 (rPBP3), containing a 6-histidine tag, was expressed in Escherichia coli BL21 (DE3). Immobilized metal affinity chromatography (IMAC) with Ni(2+)-NTA agarose was used for its purification. The purified rPBP3 was identified by SDS-PAGE and western blot analysis, and showed a single band at about 60kDa with purity higher than 95%. The penicillin-binding assay indicated that the obtained rPBP3 was functional and not hindered by the presence of the C-terminal His-tag. The protocol described in this study offers a method for obtaining purified recombinant PBP3 from P. aeruginosa CMCC 10104.
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Proteínas de Bactérias/isolamento & purificação , Sequência de Bases , Proteínas de Ligação às Penicilinas/isolamento & purificação , Pseudomonas aeruginosa/química , Deleção de Sequência , Sequência de Aminoácidos , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Dados de Sequência Molecular , Proteínas de Ligação às Penicilinas/biossíntese , Proteínas de Ligação às Penicilinas/genética , Penicilinas/química , Plasmídeos/química , Plasmídeos/metabolismo , Ligação Proteica , Sinais Direcionadores de Proteínas/genética , Pseudomonas aeruginosa/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Resistência beta-Lactâmica/genéticaRESUMO
Background: Immune checkpoint inhibitors (ICIs) have demonstrated effectiveness for advanced hepatocellular carcinoma (HCC). However, the discrepancy in the efficacy of ICIs in HCC patients with distinct etiologies has not been systematically validated. Methods: PubMed, MEDLINE, Embase, clinicaltrials.gov, and abstracts from ASCO and ESMO conferences were searched for eligible trials that explored the impact of etiology factor on the ICI treatment in HCC patients. The pooled hazard ratio (HR) of overall survival (OS) and progression-free survival (PFS), as well as the pooled odds ratio (OR) of objective response rate (ORR), were calculated with stratification of hepatitis B virus (HBV), hepatitis C virus (HCV) and nonviral subgroup, and the heterogeneity between different etiological subgroups was assessed by using an interaction test. Results: Eight eligible studies with a total of 5,646 patients were identified from searching published articles and conference abstracts. ICI therapies were associated with significantly prolonged OS with the pooled HRs of 0.78 (95% CI 0.73-0.84, p < 0.001), 0.71 (95% CI 0.65-0.79, p < 0.001), 0.80 (95% CI 0.69-0.93, p = 0.003), and 0.87 (95% CI 0.77-0.97, p = 0.011) for the whole population, HBV subgroup, HCV subgroup, and non-viral subgroup, respectively. In addition, this analysis reported a significant PFS improvement with ICI therapies with HRs of 0.78 (p = 0.004), 0.53 (p < 0.001), 0.65 (p = 0.011), and 0.81 (p = 0.107) for whole population, HBV, HCV, and nonviral subgroup, respectively. The HBV-related HCC patients showed the more distinctive HRs for OS and PFS than other etiology subgroups, and this difference was significant in PFS (p for heterogeneity = 0.001), and there was a tendency of significance in OS (p for heterogeneity = 0.079). Furthermore, the ORR advantages of ICI therapies over control were also confirmed with the pooled ORs of 3.62 (p < 0.001), 3.84 (p < 0.001), 3.05 (p < 0.001), and 2.99 (p < 0.001) for whole population, HBV, HCV, and nonviral population, respectively (p for heterogeneity = 0.743). Conclusions: ICI therapies significantly improve OS, PFS, and ORR for HCC patients with different etiologies. HBV-related HCC patients could be the highlighted population to benefit from ICI treatment.
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The physicochemical indexes and microbial diversity were investigated to compare the altered quality properties of the abdomen and cheliped muscle in swimming crab (Portunus trituberculatus) during 100 days of frozen storage at -20â. Over the extended duration of frozen storage, the sensory evaluation, moisture content, water activity (Aw), and water-holding capacity (WHC) in the abdomen and cheliped muscles of swimming crab decreased, while the pH, total volatile basic nitrogen (TVB-N), and trimethylamine (TMA) increased. The increase and decrease rates of these indicators were smaller in the abdomen than those in the cheliped muscle. High-throughput sequencing results indicated a reduction in the microbial richness and diversity in the abdomen and cheliped muscles of the swimming crab as frozen storage time extended. Proteobacteria, Actinobacteriota, and Firmicutes, Achromobacter, Kocuria, and Staphylococcus were the dominant phylum and genus in both muscle tissues, respectively. Furthermore, the correlation analysis between the composition of the microbiota and physiochemical properties revealed that the growths of Kocuria, Vibrio, Staphylococcus, and Aliiroseovarius were closely related to the physiochemical factors. The study provides a theoretical reference for quality deterioration and develops new products of different parts in the swimming crab during frozen storage.
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Citrisorbicillinol (1), along with six other known compounds (2-7), was isolated from an endphyte Penicillium citrinum ZY-2 of Plantago asiatica L. Citrisorbicillinol (1) was characterized as a skeletally unprecedented hybrid sorbicillinoid, and its unique framework is likely formed by intermolecular [4 + 2] cycloaddition between intermediates derived from citrinin and sorbicillinoid biosynthetic gene clusters. Compounds 1 and 2 demonstrated to promote osteoblastic differentiation in MC3T3-E1 cells, and to be osteogenic in the prednisolone induced osteoporotic zebrafish. Compounds 3-7 exhibited moderate cytotoxicity against four human cancer cell lines.
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Citrinina , Penicillium , Animais , Humanos , Estrutura Molecular , Peixe-ZebraRESUMO
Physicochemical properties and protein alterations in Ovalipes punctatus during cold-chain transportation were examined via sensory scores, water-holding capacity (WHC), glucose (GLU) content, catalase (CAT) activity, urea nitrogen (UN) content, and tandem mass tag (TMT)-based proteomic analysis. The results revealed that sensory characteristics and texture of crab muscle deteriorated during transportation. Proteomic analysis revealed 442 and 470 different expressed proteins (DEPs) in crabs after 18 h (FC) and 36 h (DC) of transportation compared with live crabs (LC). Proteins related to muscle structure and amino acid metabolism significantly changed, as evidenced by the decreased WHC and sensory scores of crab muscle. Glycolysis, calcium signaling, and peroxisome pathways were upregulated in the FC/LC comparison, aligning with the changes in GLU content and CAT activity, revealing the stress response of energy metabolism and immune response in crabs during 0-18 h of transportation. The downregulated tricarboxylic acid (TCA) cycle and carcinogenesis-reactive oxygen species pathways were correlated with the decreasing trend in CAT activity, suggesting a gradual retardation in both energy and antioxidant metabolism in crabs during 18-36 h of transportation. Furthermore, the regulated purine nucleoside metabolic and nucleoside diphosphate-related processes, with the increasing changes in UN content, revealed the accumulation of metabolites in crabs.
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Braquiúros , Músculos , Proteômica , Animais , Braquiúros/metabolismo , Braquiúros/química , Músculos/metabolismo , Músculos/química , Meios de Transporte , Frutos do Mar/análise , Temperatura Baixa , Espectrometria de Massas em Tandem , Alimentos Marinhos/análiseRESUMO
The effect of shrimp deveining on the quality of Pacific white shrimp muscle was investigated by analyzing the protein degradation during chilled storage via physicochemical and label-free peptidomics analyses. In this study, shrimp with intact intestines were in the control group (CS), while deveined shrimp (DS) were in the treatment group. The total viability count (TVC), total volatile base nitrogen (TVB-N) content, and trichloroacetic acid (TCA)-soluble peptide content in all of the shrimp groups gradually increased with prolonged chilled storage. However, in the later stages of chilled storage, the DS samples exhibited significantly lower TVB-N, total bacterial, and TCA-soluble peptide contents than the CS samples, indicating that deveining treatment effectively prolonged shrimp quality. The peptidomics analysis revealed varying degrees of protein hydrolysis in the DS and CS samples during chilled storage. A total of 396 differentially abundant peptides (DAPs) were identified in the DS compared with the CS, comprising 98 upregulated and 298 downregulated segments. This suggests that the removal of the intestine effectively inhibits protein hydrolysis. Gene ontology (GO) analysis suggested that the DAPs were mainly involved in catalytic activity, binding, and metabolic processes. The cluster of orthologous groups of protein (COG) analysis showed that the cytoskeleton dynamics of the muscle proteins underwent considerable alterations influenced by the shrimp's intestines during chilled storage.
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A novel "ferrate/percarbonate (Fe(VI)/SPC) co-oxidation process" was used to treat ciprofloxacin (CIP) and various micropollutants (MPs), which owned better performance than mixture of Fe(VI), Na2CO3 and H2O2. The mechanism investigation found that the low-concentration H2O2 (1-2 µM) released by SPC can promote the high-valent iron intermediates (Fe(IV)/Fe(V)) of Fe(VI) to the MP oxidation, and Fe(VI) products can also activate SPC to produce hydroxyl radical (·OH). The interactive activation of Fe(VI) and SPC was realized, which retained the high selectivity of Fe(VI) to electron-rich pollutants, and also made up the oxidation of electron-deficient pollutants through â¢OH, improving the degradation effect of various MPs by 20-30%, and the rate constant was increased by 1 to 3 times. Moreover, non-purgeable organic carbon (NPOC) determination confirmed that â¢OH participation reduced the NPOC value of CIP from 5.43 mg/L to 4.37 mg/L. The transformation pathway of CIP showed that Fe(VI)/SPC resulted in more hydroxylation intermediates of CIP than Fe(VI) alone. Acute toxicity assays found that the photoinhibition rate of CIP treated with Fe(VI) alone was 14.5%, while the sample treated with Fe(VI)/SPC showed no significant photoinhibition effect, which proved that the new process had good detoxification properties for CIP.
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Based on a typical ozone ï¼O3ï¼ pollution process in Jinan City from June 16 to 26, 2021, the variation characteristics of O3 and its precursor volatile organic compounds ï¼VOCsï¼ during different pollution periods ï¼clean period ï¼CPï¼, pollution rise period ï¼PRPï¼, heavy pollution period ï¼HPPï¼, and pollution decline period ï¼PDPï¼ï¼ in the urban area were analyzed. Both positive matrix factorization ï¼PMFï¼ and an observation-based model ï¼OBMï¼ were used to identify the main sources of VOCs, O3 production mechanisms, and sensitive species. The results showed that the average value of ρï¼O3-8hï¼ during the HPP period in the urban area was ï¼246.67±11.24ï¼ µg·m-3, and ρï¼O3-1hï¼ had a peak value of 300 µg·m-3. The volume fractions of VOCs and NO2 concentration were affected by the decrease in planetary boundary layer and wind speed, which were 76.99%-145.36% and 127.78%-141.18% higher than those in the other three periods, respectively, and were the main reasons for the aggravation of O3 pollution. Alkanes, oxygenated volatile organic compounds ï¼OVOCsï¼, and halogenated hydrocarbons accounted for 43.81%, 20.98%, and 17.43% of VOCs in urban areas, respectively. All of them showed significant growth during the HPP period, with acetone, propane, and ethane being the top three species by volume in each stage and isopentane showing the highest growth during the HPP period. Alkene, alkanes, and aromatic hydrocarbons accounted for 40.19%, 28.06%, and 21.92% of the ozone generation potential ï¼OFPï¼. 1-butene, toluene, isopentane, and isoprene were the species with higher OFP. Isoprene had the highest OFP during the PRP phase, and 1-butene had the highest OFP during the HPP phase. The volume fraction of isopentane significantly increased OFP. The correlation coefficient between VOCs and CO preliminarily indicated that motor vehicle exhaust and oil and gas volatilization were the main sources of VOCs during the HPP period. Further use of PMF revealed that solvent use sources, combustion sources, motor vehicle exhaust+oil and gas volatilization sources, industrial emission sources, and plant sources were important sources of VOCs in urban areas. The contribution of motor vehicle exhaust+oil and gas volatilization sources in the HPP period to VOCs was 3.09-14.72 times higher than that in other periods. The contribution of solvent use sources to VOCs was approximately 2.50 times higher than that in the CP and PRP periods. The main sources of VOCs volume fraction increase were motor vehicle exhaust, oil and gas volatilization sources, and solvent use sources. Potential sources and concentration weight analysis found that VOCs were also affected by the transmission of VOCs to Binzhou and Dongying in the northeast direction. The OBM results indicated that the main pathway of O3 formation in urban areas was the reaction of peroxide hydroxyl radicals ï¼HO2·ï¼ and methyl peroxide radicals ï¼CH3O2·ï¼ with NO, and the net ozone generation rate during the HPP phase [Pï¼O3ï¼net] was 24×10-9 h-1. Based on the sensitivity experiment results, the alkene components of 1-butene, propylene, cis-2-butene, and ethylene were the dominant species for O3 production.
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Hard carbon has been widely used in anode of lithium/sodium ion battery, electrode of supercapacitor, and carbon molecular sieve for CO2 capture and hydrogen storage. In this study the lignin derived hard carbon products are investigated, and the conclusions are abstracted as follows. (1) The lignin derived hard carbon products consist of microcrystal units of sp2 graphene fragments, jointed by sp3 carbon atoms and forming sp2-sp3 hybrid hard carbon family. (2) From the lignin precursors to the sp2-sp3 hybrid hard carbon products, most carbon atoms retain their original electron configurations (sp2 or sp3) and keep their composition in lignin. (3) The architectures of lignin-derived hard carbon materials are closely dependent on the forms of their lignin precursors, and could be preformed by different pretreatment techniques. (4) The carbonization of lignin precursors follows the mechanism "carbonization in situ and recombination nearby". (5) Due to the high carbon ratio and abundant active functional groups in lignin, new activation techniques could be developed for control of pore size and pore volume. In general lignin is an excellent raw material for sp2-sp3 hybrid hard carbon products, a green and sustainable alternative resource for phenolic resin, and industrial production for lignin derived hard carbon products would be feasible.
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Complete and unambiguous (1)H and (13)C NMR chemical shift assignments for all-trans-retinal, 13-cis-retinal, 11-cis-retinal and 9-cis-retinal (1-4) have been established by means of two-dimensional COSY, HSQC, HMBC and NOESY spectroscopic experiments.