Hydrochar and Its Dissolved Organic Matter Aged in a 30-Month Rice-Wheat Rotation System: Do Primary Aging Factors Alter at Different Stages?

Hydrochar, recognized as a green and sustainable soil amendment, has garnered significant attention. However, information on the aging process in soil and the temporal variability of hydrochar remains limited. This study delves deeper into the interaction between hydrochar and soil, focusing on primary factors influencing hydrochar aging during a 30-month rice-wheat rotation system. The results showed that the initial aging of hydrochar (0-16 months) is accompanied by the development of specific surface area and leaching of hydrochar-derived dissolved organic matter (HDOM), resulting in a smaller particle size and reduced carbon content. The initial aging also features a mineral shield, while the later aging (16 to 30 months) involves surface oxidation. These processes collectively alter the surface charge, hydrophilicity, and composition of aged hydrochar. Furthermore, this study reveals a dynamic interaction between the HDOM and DOM derived from soil, plants, and microbes at different aging stages. Initially, there is a preference for decomposing labile carbon, whereas later stages involve the formation of components with higher aromaticity and molecular weight. These insights are crucial for understanding the soil aging effects on hydrochar and HDOM as well as evaluating the interfacial behavior of hydrochar as a sustainable soil amendment.

Bibliometric analysis of biochar-based organic fertilizers in the past 15 years: Focus on ammonia volatilization and greenhouse gas emissions during composting.

Biochar-based organic fertilizer is a new type of ecological fertilizer formulated with organic fertilizers using biochar as the primary conditioning agent, which has received wide attention and application in recent years. This study conducted a comprehensive bibliometric analysis of the main hot spots and research trends in the field of biochar-based organic fertilizer research by collecting indicators (publication year, number, prominent authors, and research institutions) in the Web of Science database. The results showed that the research in biochar-based organic fertilizer has been in a rapid development stage since 2015, with exponential growth in publications number; the main institution with the highest publications number was Northwest Agriculture & Forestry University; the researchers with the highest number of publications was Mukesh Kumar Awasthi; the most publications country is China by Dec 30, 2022. The hot spots of biochar-based organic fertilizer research have been nitrogen utilization, greenhouse gas emission, composting product quality and soil fertility. Biochar reduces ammonia volatilization and greenhouse gas emissions from compost mainly through adsorption. The results showed that adding 10% biochar was an effective measure to achieve co-emission reduction of ammonia and greenhouse gases in composting process. In addition, biochar modification or combination with other additives should be the focus of future research to mitigate ammonia and greenhouse gas emissions from composting processes.

Up-regulating microRNA-214-3p relieves hypoxic-ischemic brain damage through inhibiting TXNIP expression.

A list of microRNAs (miRs) has been referred to involve in the development of hypoxic-ischemic brain damage (HIBD). Based on that, we probed the concrete role of miR-214-3p regulating thioredoxin-interacting protein (TXNIP) in the illness. A neonatal HIBD mouse model was established using the Rice-Vannucci method, followed by measurements of miR-214-3p and TXNIP levels in brain tissues. After modeling, mice were given brain injection of the compounds that could alter miR-214-3p and TXNIP expression. Afterward, neurological function, neuronal inflammation, neuronal apoptosis, neuron morphology, and the number of Nissl body were assessed in HIBD mice. The binding of miR-214-3p to TXNIP was analyzed. Lower miR-214-3p and higher TXNIP were analyzed in brain tissues of mice with HIBD. Up-regulating miR-214-3p or depleting TXNIP improved neurological function, reduced neuronal inflammation and neuronal apoptosis, attenuated morphological damage of neurons, and increased the number of Nissl bodies in mice with HIBD. TXNIP was targeted by miR-214-3p and overexpressing TXNIP reversed the therapeutic effect of miR-214-3p on HIBD mice. It is noted that promotion of miR-214-3p relieves HIBD in mice through inhibiting TXNIP expression.

Development and evaluation of a rehabilitation training compliance scale for patients with urinary incontinence.

BACKGROUND: Urinary incontinence treatment includes conservative treatment, physical devices, medication, and surgery. Pelvic floor muscle training combined with bladder training is among the most effective, non-invasive, and economical ways to treat urinary incontinence, and compliance with training is essential in urinary incontinence treatment. Several instruments assess pelvic floor muscle training and bladder training. However, no tool has been found that assesses compliance with pelvic floor muscle training when combined with bladder training for urinary incontinence. This study aimed to develop a rehabilitation training compliance scale for patients with urinary incontinence and to evaluate its validity and reliability. METHODS: This study was performed in two tertiary hospitals in Hainan, China between December 2020 and July 2021, 123 patients were included. A literature review, group discussions, and two rounds of letter consultations were performed to acquire the item pool and finalise the 12 items for this scale. Exploratory and confirmatory factor analysis, Cronbach's α, split-half reliability, test-retest reliability, content validity, construct validity, convergent and discriminant validity, and criterion-related validity were used to examine the items in the scale. RESULTS: A 12-item scale comprising three factors accounted for 85.99% of the variance in the data. The Cronbach's α, split-half reliability, test-retest reliability, and content validity index of the scale were 0.95, 0.89, 0.86, and 0.93, respectively. Comparison with the Chen pelvic floor muscle exercise self-efficacy scale showed high calibration correlation validity (coefficient = 0.89). CONCLUSIONS: The training compliance scale developed in this study is a valid and reliable measurement tool to assess pelvic floor muscle training and bladder training compliance in patients with urinary incontinence.

Foliar application of procyanidins enhanced the biosynthesis of 2-acetyl-1-pyrroline in aromatic rice (Oryza sativa L.).

BACKGROUND: Procyanidins is a polyphenolic compound with multiple properties. However, the application of exogenous procyanidins in crops has not been reported. Aromatic rice is a high-quality rice with a special aroma and popular with consumers. The 2-acetyl-1-pyrroline (2-AP) is a key compound of aromatic rice aroma. In the current study, aromatic rice plants were sprayed with procyanidins solutions at 0.25 (Pr0.25), 0.50 (Pr0.50), 1.00 (Pr1.00), 2.00 (Pr2.00) g L-1, respectively and treatment sprayed with distilled water was taken as control (CK). The effects of exogenous procyanidins on growth and 2-AP biosynthesis of aromatic rice plants were explored. RESULTS: Compared with CK, Pr1.00 and Pr2.00 treatments significantly increased 2-AP content by 16.67% and 37.68%, respectively. Higher proline, 1-pyrroline-5-carboxylic acid (P5C), 1-pyrroline, methylglyoxal contents, and lower γ- aminobutyric acid (GABA) content were recorded in Pr1.00 and Pr2.00 treatments than CK. Compared with CK, Pr1.00 and Pr2.00 treatments significantly improved the activities of P5CS and OAT and diminished the activity of BADH. Furthermore, compared with CK, Pr1.00 and Pr2.00 treatments significantly up-regulated the transcript levels of P5CS2, P5CR, OAT, DAO4 and down-regulated the transcript levels of BADH2. Exogenous procyanidins had no substantial effects on plant height, stem diameter, fresh weight, and dry weight of aromatic rice plants. CONCLUSIONS: In conclusion, our findings reported the increment of 2-AP content in aromatic rice under exogenous procyanidins. Our results indicated that the application of exogenous procyanidins enhanced 2-AP biosynthesis by improving proline biosynthesis and inhibiting GABA formation.

Water quality and periphyton functional response to input of dissolved manure-derived hydrochars (DHCs).

Dissolved organic matter (DOM) plays a critical role in the global carbon cycle and provides food and energy for aquatic organisms. Recently, hydrochar, as a solid carbonaceous substance derived from hydrothermal carbonization, has been increasingly used as a soil amendment. Upon entering the soil, dissolved components (DHCs) were released from hydrochar as exogenous DOM, finally entering the aquatic ecosystems by runoff, which participates in environmental geochemical processes. However, relevant reports revealing the response of the aquatic ecosystem to the input of DHCs remain insufficiently elucidated. For the first time, the fundamental features of DHCs and their influence on water quality and aquatic biological function were investigated in this study. DHCs at 260 °C (DHC260) had lower yields, a greater [C/N], worse biodegradability, and larger humic acid relative amounts than did DHCs at 180 °C (DHC180). The DHC structural alterations in periphyton-incubated aquatic ecosystems suggested that protein substances were more easily degraded or assimilated by periphyton, especially for DHC180, with rates of decrease of 34.5-63.5%. The increased chemical oxygen demand (COD) degradation in the DHC260 treatments was most likely due to humic acid substances with higher COD equivalents. Furthermore, DHC260 caused phosphorus to accumulate in periphyton, reducing aquatic phosphorus concentration. Notably, the abundances of Flavobacteria and Cyanobacteria associated with water blooms increased 12.7-25.5- and 1.3-8.3-fold, respectively; consequently, the promotional impact of DHCs on algal blooms should be considered. This result extends the nonnegligible role of DHCs in aquatic ecosystems and underlines the need to regulate the hydrochar application process.

Identification of QTL related to anther color and hull color by RAD sequencing in a RIL population of Setaria italica.

BACKGROUND: Foxtail millet (Setaria italica) is one of the oldest domesticated crops and has been considered as an ideal model plant for C4 grasses. It has abundant type of anther and hull colors which is not only a most intuitive morphological marker for color selection in seed production, but also has very important biological significance for the study of molecular mechanism of regulating the synthesis and metabolism of flavonoids and lignin. However, only a few genetic studies have been reported for anther color and hull color in foxtail millet. RESULTS: Quantitative trait loci (QTL) analysis for anther color and hull color was conducted using 400 F6 and F7 recombinant inbreed lines (RILs) derived from a cross between parents Yugu18 and Jigu19. Using restriction-site associated DNA sequencing, 43,001 single-nucleotide polymorphisms (SNPs) and 3,022 indels were identified between both the parents and the RILs. A total of 1,304 bin markers developed from the SNPs and indels were used to construct a genetic map that spanned 2196 cM of the foxtail millet genome with an average of 1.68 cM/bin. Combined with this genetic map and the phenotypic data observed in two locations for two years, two QTL located on chromosome 6 (Chr6) in a 1.215-Mb interval (33,627,819-34,877,940 bp) for anther color (yellow - white) and three QTL located on Chr1 in a 6.23-Mb interval (1-6,229,734 bp) for hull color (gold-reddish brown) were detected. To narrow the QTL regions identified from the genetic map and QTL analysis, we developed a new method named "inconsistent rate analysis" and efficiently narrowed the QTL regions of anther color into a 60-kb interval (34.13-34.19 Mb) in Chr6, and narrowed the QTL regions of hull color into 70-kb (5.43-5.50 Mb) and 30-kb (5.69-5.72 Mb) intervals in Chr1. Two genes (Seita.6G228600.v2.2 and Seita.6G228700.v2.2) and a cinnamyl alcohol dehydrogenase (CAD) gene (Seita.1G057300.v2.2) with amino acid changes between the parents detected by whole-genome resequencing were identified as candidate genes for anther and hull color, respectively. CONCLUSIONS: This work presents the related QTL and candidate genes of anther and hull color in foxtail millet and developed a new method named inconsistent rate analysis to detect the chromosome fragments linked with the quality trait in RILs. This is the first study of the QTL related to hull color in foxtail millet and clarifying that the CAD gene (Seita.1G057300.v2.2) is the key gene responsible for this trait. It lays the foundation for further cloning of the functional genes and provides a powerful tool to detect the chromosome fragments linked with quality traits in RILs.

Cystatin C is a potential predictor of unfavorable outcomes for cerebral ischemia with intravenous tissue plasminogen activator treatment: A multicenter prospective nested case-control study.

BACKGROUND AND PURPOSE: The aim of this study was to explore whether cystatin C (CysC) could be used as a potential predictor of clinical outcomes in acute ischemic stroke (AIS) patients treated with intravenous tissue plasminogen activator (IV-tPA). METHODS: We performed an observational study including a retrospective analysis of data from 125 AIS patients with intravenous thrombolysis. General linear models were applied to compare CysC levels between groups with different outcomes; logistic regression analysis and receiver-operating characteristic curves were adopted to identify the association between CysC and the therapeutic effects. RESULTS: Compared with the "good and sustained benefit" (GSB) outcome group (defined as ≥4-point reduction in National Institutes of Health Stroke Scale or a score of 0-1 at 24 h and 7 days) and the "good functional outcome" (GFO) group (modified Rankin Scale score 0-2 at 90 days), serum CysC baseline levels were increased in the non-GSB and non-GFO groups. Logistic regression analysis found that CysC was an independent negative prognostic factor for GSB (odds ratio [OR] 0.010; p = 0.005) and GFO (OR 0.011; p = 0.021) after adjustment for potential influencing factors. Receiver-operating characteristic curves showed the CysC-involved combined models provided credible efficacy for predicting post-90-day favorable clinical outcome (area under the curve 0.86; p < 0.001). CONCLUSIONS: Elevated serum CysC is independently associated with unfavorable clinical outcomes after IV-tPA therapy in AIS. Our findings provide new insights into discovering potential mediators for neuropathological process or treatment in stroke.

Determination of seventeen major and trace elements in new float glass standards for use in forensic comparisons using laser ablation inductively coupled plasma mass spectrometry.

Consensus concentration values for seventeen (17) major and trace elements typically present in soda-lime glass manufactured using the "float " process and used in the quantitative analysis and forensic comparison of glass samples were determined using laser ablation (LA) micro sampling coupled to inductively coupled plasma mass spectrometry (ICP-MS). This is the first reporting of the chemical characterization of a new set of float glass intended for use as matrix-matched calibration standards in the forensic analysis and comparison of glass by LA-ICP-MS using a standard test method (ASTM E2927-16e1). Three Corning Float Glass Standards (CFGS) were manufactured at low, medium, and high concentrations of 32 elements typically encountered in float glass samples as found in forensic casework. This work describes an international collaboration among seven (7) laboratories to evaluate the homogeneity of the three glass materials and reports the consensus concentrations values of 17 elements at three concentration levels. Eight (8) sets of independent results from LA-ICP-MS analysis using the standard test method of analysis and one set of micro-X-ray Fluorescence Spectrometry (µXRF) data (using method ASTM E2926-17) resulted in typically <3% relative standard deviation (RSD) within each lab and < 5% RSDs among all labs participating in the study for the concentration ranges using sampling spots between 50 µm - 100 µm in diameter. These results suggest that the new calibration standards are homogeneous for most elements at the small sampling volumes (~ 90 µm deep by ~80 µm in diameter) reported and show excellent agreement among the different participating labs. Consensus concentration values are determined using a previously reported calibration standard (FGS 2) and checked with a NIST 1831 SRM®. A collaboration with National Institute of Standards and Technology (NIST) scientists to certify these glasses as SRMs, including the certification of the quantitative analysis of the minor and trace element content, for future distribution by NIST is ongoing.

Molecular and biochemical characterizations of a new cold-active and mildly alkaline ß-Mannanase from Verrucomicrobiae DG1235.

Mannanases catalyze the cleavage of ß-1,4-mannosidic linkages in mannans and have various applications in different biotechnological industries. In this study, a new ß-mannanase from Verrucomicrobiae DG1235 (ManDG1235) was biochemically characterized and its enzymatic properties were revealed. Amino acid alignment indicated that ManDG1235 belonged to glycoside hydrolase family 26 and shared a low amino acid sequence identity to reported ß-mannanases (up to 50% for CjMan26C from Cellvibrio japonicus). ManDG1235 was expressed in Escherichia coli. Purified ManDG1235 (rManDG1235) exhibited the typical properties of cold-active enzymes, including high activity at low temperature (optimal at 20 °C) and thermal instability. The maximum activity of rManDG1235 was achieved at pH 8, suggesting that it is a mildly alkaline ß-mannanase. rManDG1235 was able to hydrolyze a variety of mannan substrates and was active toward certain types of glucans. A structural model that was built by homology modeling suggested that ManDG1235 had four mannose-binding subsites which were symmetrically arranged in the active-site cleft. A long loop linking ß2 and α2 as in CjMan26C creates a steric border in the glycone region of active-site cleft which probably leads to the exo-acting feature of ManDG1235, for specifically cleaving mannobiose from the non-reducing end of the substrate.

Regulation of immune-driven pathogenesis in Parkinson's disease by gut microbiota.

Parkinson's disease (PD) is one of the most significant medical and social burdens of our time. The prevalence of PD increases with age and the number of individuals diagnosed with PD is expected to double from 6.9 million in 2015 to 14.2 million in 2040. To date, no drugs can stop the ongoing neurodegeneration caused by PD due to its unclear and complex pathogenic mechanisms. It has been wildly recognized that both gut microbiota and neuro-immunity are involved in the pathology of PD. In this review, we intend to provide a comprehensive overview of current knowledge on how gut microbiota involved in immune-driven pathogenesis of PD, and its potential as a new target of dietary and/or therapeutic interventions for PD.

Vibrio vulnificus meningoencephalitis in a patient with thalassemia and a splenectomy.

Vibrio vulnificus usually causes wound infection, gastroenteritis, and septicemia. However, it is a rare conditional pathogen causing meningoencephalitis. We report a case of a young, immunocompromised man presenting with severe sepsis after exposure to sea water and consumption of seafood. The patient subsequently developed meningoencephalitis, and Vibrio vulnificus was isolated from his blood culture. The sequence was confirmed by Next-generation sequencing of a sample of cerebrospinal fluid, as well as from a bacteria culture. After the pathogen was detected, the patient was treated with ceftriaxone, doxycycline, and moxifloxacin for 6 weeks, which controlled his infection. In this case, we acquired his clinical and dynamic MRI presentations, which were never reported. Physicians should consider Vibrio vulnificus infections when they see a similar clinical course, brain CT and MRI findings, susceptibility factors and recent seafood ingestion or exposure to seawater. Due to high mortality, the early diagnosis and treatment of Vibrio vulnificus infections are crucial. Next-generation sequencing was found to be useful for diagnosis.

[Network Meta-analysis of 3 kinds of Chinese medicine injections in treatment of acute exacerbations of chronic obstructive pulmonary disease].

To evaluate the efficacy and safety of traditional Chinese medicine injections( CMI) in the treatment of acute exacerbation of chronic obstructive pulmonary disease( AECOPD). PubMed,Cochrane Library,CNKI,CBM,Wan Fang and VIP database( since the date of database establishment to July 2018) were retrieved through computer for controlled randomized trials( CRTs) of 3 kinds of traditional Chinese medicine injections( Chuankezhi Injection,Tanreqing Injection,Xuebijing Injection) for AECOPD. After the methodological quality of included researches were evaluated,and the valid data were extracted,statistical analysis was performed with Stata 14,RevMan 5.3 is used for risk bias map. There were including 4 RCTs and 20 quasi-RCTs,which involving 579 patients.The results of network Meta-analysis showed that: ①there were significant differences in the forced expiratory volume in the first second between the 3 CMI and control groups,and there was no significant difference between CMI; ②3 kinds of CMI adjuvant therapy AECOPD,According to the forced expiratory volume in the first second of the probability ranking results,Tanreqing Injection is more effective,followed by Xuebijing Injection and Chuankezhi Injection. Based on the present evidence,3 kinds of CMI can improve the forced expiratory volume in the first second on the basis of Western medicine routine treatment of AECOPD,having better safty. In addition,the conclusion of this study still needs a large number of RCTs with reasonable design and proper method to confirm it.

Identification of a novel DNMT1 mutation in a Chinese patient with hereditary sensory and autonomic neuropathy type IE.

BACKGROUND: DNA methyltransferase 1 (EC 2.1.1.37), encoded by DNMT1 gene, is one of key enzymes in maintaining DNA methylation patterns of the human genome. It plays a crucial role in embryonic development, imprinting and genome stability, cell differentiation. The dysfunction of this group of enzymes can lead to a variety of human genetic disorders. Until now, mutations in DNMT1 have been found to be associated with two distinct phenotypes. Mutations in exon 20 of this gene leads to hereditary sensory and autonomic neuropathy type IE, and mutations in exon 21 cause autosomal dominant cerebellar ataxia, deafness and narcolepsy. CASE PRESENTATION: Here we report a novel DNMT1 mutation in a sporadic case of a Chinese patient with cerebellar ataxia, multiple motor and sensory neuropathy, hearing loss and psychiatric manifestations. Furthermore, we elucidated its pathogenic effect through molecular genetics studies and revealed that this defective DNMT1 function is responsible for the phenotypes in this individual. CONCLUSION: Our findings expand the spectrum of DNMT1-related disorders and provide a good example of precision medicine through the combination of exome sequencing and clinical testing.

Mechanism and kinetics of dye desorption from dye-loaded carbon (XC-72) with alcohol-water system as desorbent.

In this paper, alcohol (methanol, ethanol, n-propanol)-water system was used as solution for the desorption of Acid Orange 7 (AO7), Ponceau 2R and Rhodamine B (RhB) from dye-loaded carbon (XC-72). Excellent degradation efficiency was obtained (desorption efficiency reaches 77.35%, 85.60%, 96.86% for Ponceau 2R, AO7 and Rhodamine B, respectively) and it was significantly influenced by alcohol content and the length of carbon chain in alcohol (hydrophobicity). In addition, desorption kinetics was fitted by a second-order desorption model, and the desorbed quantity at equilibrium (qe) and rate constant (kd) were calculated, respectively.

Efficacy of Solitaire Stent Arterial Embolectomy in Treating Acute Cardiogenic Cerebral Embolism in 17 Patients.

BACKGROUND Thrombolysis with rtPA is the only accepted drug therapy for acute ischemic stroke. Since acute cerebral stroke is so pervasive, newly developed recanalization methods have the potential for wide-ranging impacts on patient health and safety. We explored the efficacy and safety of Solitaire stent arterial embolectomy in the treatment of acute cardiogenic cerebral embolism. MATERIAL AND METHODS Between October 2012 and June 2015, 17 patients underwent Solitaire stent arterial embolectomy, either alone or in combination with rtPA intravenous thrombolysis, to treat acute cardiogenic cerebral embolism. Sheath placement time, vascular recanalization time, number of embolectomy attempts, and IV rtPA dose and time were recorded. Success and safety of the recanalization procedure, as well as clinical outcomes, were assessed. These results were compared to 16 control patients who were treated using only rtPA IV thrombolysis. RESULTS Full recanalization of the occluded arteries was achieved in 15 (88.2%) of the Solitaire stent patients. NIH Stroke Scale scores of embolectomy patients improved by an average of 12.59 ± 8.24 points between admission and discharge, compared to 5.56 ± 5.96 in the control group (P<0.05). Glasgow Coma Score improvement between admission and discharge was also significantly higher in the embolectomy group (P<0.05). There was no significant difference in symptomatic intracerebral hemorrhage, high perfusion encephalopathy, incidence of hernia, or mortality between the 2 groups (P>0.05). CONCLUSIONS Solitaire stent embolectomy is a safe and effective alternative to simple venous thrombolytic therapy, and it can significantly improve short-term neurological function and long-term prognosis in acute cardiogenic cerebral embolism.

Studies on competitive adsorption of dyes onto carbon (XC-72) and regeneration of adsorbent.

Carbon as an adsorbent has been widely studied for wastewater treatment, but the regeneration of adsorbent has been scarcely reported. In this paper, an economical and environmental method was applied to regenerate carbon (XC-72). Results showed that both anhydrous ethanol and deionized water did not obtain optimal effect for the desorption of Acid Orange 7, Ponceau 2R and Rhodamine B, but the desorption effect was dramatically improved when anhydrous ethanol and deionized water were mixed in a certain volume ratio. In addition, the adsorption kinetics of the three dyes were investigated, which showed that the process of adsorption could be well represented by the pseudo-second-order model. For the study of competitive adsorption, this indicated that the interaction between adsorbent and adsorbate had something to do with electrostatic attraction.

Property of Cu2O-CuO/ZSM-5 nanocomposite and degradation process of azo dye AO7 without sacrificial agent (H2O2).

In this study, Cu2O-CuO/ZSM-5 nanocomposite was synthesized by the impregnation method, and its catalytic performance for the destruction of AO7 in aqueous solutions was investigated. The morphology, structure and surface element valence state of Cu2O-CuO/ZSM-5 were characterized by transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The operating conditions on the degradation of AO7 by Cu2O-CuO/ZSM-5, such as initial pH values, concentration of AO7 and catalyst dosage were investigated and optimized. The results showed that the sample had good catalytic activity for destruction of AO7 in the absence of a sacrificial agent (e.g. H2O2): it could degrade 91% AO7 in 140 min at 25 °C and was not restricted by the initial pH of the AO7 aqueous solutions. Cu2O-CuO/ZSM-5 exhibited stable catalytic activity with little loss after three successive runs. The total organic carbon and chemical oxygen demand removal efficiencies increased rapidly to 69.36% and 67.3% after 120 min of treatment by Cu2O-CuO/ZSM-5, respectively.

I2-Catalyzed Aerobic Oxidative C(sp(3))-H Amination/C-N Cleavage of Tertiary Amine: Synthesis of Quinazolines and Quinazolinones.

An iodine-catalyzed oxidative C(sp(3))-H amination/C-N cleavage of tertiary amines couducted under an oxygen atmosphere has been developed and affords a route to quinazolines and quinazolinones in good to excellent yields via a domino ring annulation. The method is metal-free, peroxide-free, and operationally simple to implement with a wide scope of substrates and represents a new avenue for multiple C-N bond formations.

A biomimetic enzyme modified electrode for H2O2 highly sensitive detection.

An efficient catalyst based on artificial bionic peroxidase was synthesized for electrocatalysis. A poly(ethyleneimine)/Au nanoparticle composite (PEI-AuNP) was prepared and it was then linked to hemin via a coupling reaction between carboxyl groups in hemin and amino groups in PEI without the activation of a carboxyl group by carbodiimide. Fourier transform infrared (FTIR) spectroscopy verified the formation of amido bonds within the structure. The presence of AuNPs contributed greatly in establishing the amido bonds within the composite. Transmission electron microscopy (TEM) and UV-visible spectroscopy were also used to characterize the PEI-AuNP-hemin catalyst. PEI-AuNP-hemin exhibited intrinsic peroxidase-like catalytic activities. The PEI-AuNP-hemin deposited on a glass carbon electrode had strong sensing for H2O2 with a well-defined linear relationship between the amperometric response and H2O2 concentration in the range from 1 µM to 0.25 mM. The detection limit was 0.247 nM with a high sensitivity of 0.347 mA mM(-1) cm(-2). The peroxidase-like catalytic activity of PEI-AuNP-hemin is discussed in relation to its microstructure. The study suggests that PEI-AuNP-hemin may have promising application prospects in biocatalysis and bioelectronics.