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1.
Small ; 20(22): e2310266, 2024 May.
Article in English | MEDLINE | ID: mdl-38098346

ABSTRACT

The interactions between the catalyst and support are widely used in many important catalytic reactions but the construction of strong interaction with definite microenvironments to understand the structure-activity relationship is still challenging. Here, strongly-interacted composites are prepared via selective exsolution of active NiSe2 from the host matrix of NiFe2O4 (S-NiSe2/NiFe2O4) taking advantage of the differences of migration energy, in which the NiSe2 possessed both high dispersion and small size. The characteristics of spatially resolved scanning transmission X-ray microscopy (STXM) coupled with analytical Mössbauer spectra for the surface and bulk electronic structures unveiled that this strongly interacted composite triggered more charge transfers from the NiSe2 to the host of NiFe2O4 while stabilizing the inherent atomic coordination of NiFe2O4. The obtained S-NiSe2/NiFe2O4 exhibits overpotentials of 290 mV at 10 mA cm-2 for oxygen evolution reaction (OER). This strategy is general and can be extended to other supported catalysts, providing a powerful tool for modulating the catalytic performance of strongly-interacted composites.

2.
Angew Chem Int Ed Engl ; : e202406711, 2024 Jun 24.
Article in English | MEDLINE | ID: mdl-38923764

ABSTRACT

Spin state is often regarded as the crucial valve to release the reactivity of energy-related catalysts, yet it is also challenging to precisely manipulate, especially for the active center ions occupied at the specific geometric sites. Herein, a π-π type orbital coupling of 3d (Co)-2p (O)-4f (Ce) was employed to regulate the spin state of octahedral cobalt sites (CoOh) in the composite of Co3O4/CeO2. More specifically, the equivalent high-spin ratio of CoOh can reach to 54.7% via tuning the CeO2 content, thereby triggering the average eg filling (1.094) close to the theoretical optimum value. The corresponding catalyst exhibits a superior water oxidation performance with an overpotential of 251 mV at 10 mA cm-2, rivaling most cobalt-based oxides state-of-the-art. The π-π type coupling corroborated by the matched energy levels between Ce t1u/t2u-O and CoOh t2g-O π type bond in the calculated crystal orbital Hamilton population and partial density of states profiles, stimulates a π-donation between O 2p and π-symmetric Ce 4fyz2 orbital, consequently facilitating the electrons hopping from t2g to eg orbital of CoOh. This work offers an in-depth insight into understanding the 4f and 3d orbital coupling for spin state optimization in composite oxides.

3.
J Environ Manage ; 347: 119152, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-37774660

ABSTRACT

The stormwater biofilter is a prevailing green infrastructure for urban stormwater management, but it is less effective in dissolved nitrogen removal, especially for nitrate. The mechanism that governs the nitrate leaching and performance stability of stormwater biofilters is poorly understood. In this study, a water quality model was developed to predict the ammonium and nitrate dynamics in a biochar-pyrite amended stormwater biofilter. The transport of dissolved nitrogen species was described by advection-dispersion models. The kinetics of adsorption and pyrite-based autotrophic denitrification are included in the model and simulated with a steady-state saturated flow. The model was calibrated and validated using eleven storm events. The modeling results reveal that the contribution of pyrite-based autotrophic denitrification to nitrate leaching alleviation improves with the increased drying duration. The nitrate removal efficiency was affected by a series of design parameters. Pyrite filling rate has a minor effect on nitrate removal promotion. Service area ratio and submerged zone depth are the key parameters to prevent nitrate leaching, as they influence the emergence and discharge time of nitrate breakthrough. The high inflow volume (high service area ratio) and small submerged zone can lead to earlier and increased discharge of peak nitrate otherwise the peak nitrate could be retained in the submerged zone and denitrified during the drying period. The developed mechanistic model provides a useful tool to evaluate the treatment ability of stormwater biofilters under varying conditions and offers a guideline for biofilter design optimization.


Subject(s)
Nitrates , Nitrogen , Iron , Denitrification
4.
Bioprocess Biosyst Eng ; 45(5): 969-979, 2022 May.
Article in English | MEDLINE | ID: mdl-35312865

ABSTRACT

Curdlan is an edible microbial polysaccharide and can be used in food, biomedical and biomaterial fields. To reduce the cost of curdlan production, this study investigated the suitability of cassava starch hydrolysates as carbon source for curdlan production. Cassava starch was hydrolyzed into maltose syrup using ß-amylase and pullulanase at various enzyme dosages, temperature, time and addition order of two enzymes. The maltose yield of 53.17% was achieved at starch loading 30% by simultaneous addition ß-amylase 210 U/g starch and pullulanase 3 U/g starch at 60 °C for 9 h. Cassava starch hydrolysates were used as carbon source for curdlan production by Agrobacterium sp. DH-2. The curdlan production reached 28.4 g/L with the yield of 0.79 g/g consumed sugar and molecular weight of 1.26 × 106 Da at 96 h with cassava starch hydrolysate at 90 g/L initial sugar concentration. Curdlan produced from cassava starch hydrolysates was characterized using FT-IR spectra and thermo gravimetric analysis. This work indicated that cassava starch was a potential renewable feedstock for curdlan production.


Subject(s)
Manihot , beta-Amylase , Agrobacterium , Carbon , Maltose , Spectroscopy, Fourier Transform Infrared , Starch , beta-Glucans
5.
Molecules ; 27(19)2022 Sep 21.
Article in English | MEDLINE | ID: mdl-36234712

ABSTRACT

It was recently revealed that naturally occurring myricetin can inhibit ectonucleotidase ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), which, in turn, can treat ischemic cardiac injury. However, due to myricetin's poor druggability, its further developments are relatively limited, which necessitates the discovery of novel ENPP1-inhibiting myricetin analogs as alternatives. In this study, the binding model of myricetin with ENPP1 was elucidated by molecular docking and molecular dynamics studies. Subsequently, virtual screening on the self-developed flavonoid natural product database (FNPD), led to the identification of two flavonoid glycosides (Cas No: 1397173-50-0 and 1169835-58-8), as potential ENPP1 inhibitors. Docking scores and MM/GBSA binding energies predicted that they might have higher inhibitory effects than myricetin. This study provides a strong foundation for the future development of ischemic cardiac injury drugs.


Subject(s)
Biological Products , Molecular Dynamics Simulation , Flavonoids/chemistry , Flavonoids/pharmacology , Glycosides , Humans , Molecular Docking Simulation , Phosphoric Diester Hydrolases/chemistry , Pyrophosphatases
6.
Angew Chem Int Ed Engl ; 61(34): e202207600, 2022 Aug 22.
Article in English | MEDLINE | ID: mdl-35764600

ABSTRACT

The electronic structure of composites plays a critical role in photocatalytic conversion, whereas it is challenging to modulate the orbital for an efficient catalyst. Herein, we regulated the t2g orbital occupancy state of Ti to realize efficient CO2 conversion by adjusting the amount of photo-deposited Cu in the Cu/TiO2 composite. For the optimal sample, considerable electrons transfer from the Cu d orbital to the Ti t2g orbital, as proven by X-ray absorption spectroscopy. The Raman spectra results also corroborate the electron enrichment on the Ti t2g orbital. Further theoretical calculations suggested that the orbital energy of the Ti 3d orbital in TiO2 is declined, contributing to accepting Cu 3d electrons. As a result, the Cu/TiO2 composite exhibited an extremely high selectivity of 95.9 % for CO, and the productivity was 15.27 µmol g-1 h-1 , which is almost 6 times that of the original TiO2 . Our work provides a strategy for designing efficient photocatalysis as a function of orbital regulation.

7.
Nanotechnology ; 33(9)2021 Dec 06.
Article in English | MEDLINE | ID: mdl-34808610

ABSTRACT

Oxygen vacancies are considered to be an important factor to influence the electronic structure and charge transport of electrocatalysts in the field of energy chemistry. Various strategies focused on oxygen vacancy engineering are proved to be efficient for further improving the electrocatalytic performance of Co3O4. Herein, an optimal Co3O4with rich oxygen vacancies have been synthesized via a two-step process combining solution reduction and Ni2+impregnation. The as-prepared electrocatalyst exhibits an enhanced oxygen evolution performance with the overpotential of 330 mV at the current density of 10 mA cm-2in alkaline condition, which is 84 mV lower than that of pristine one. With the increasing of oxygen vacancies, the charge transfer efficiency and surface active area are relatively enhanced reflected by the Tafel slope and double-layer capacitance measurement. These results indicate that combination of solution reduction and heteroatom doping can be a valid way for efficient metal oxides-based electrocatalyst development by constructing higher concentration of oxygen vacancy.

8.
J Environ Manage ; 297: 113211, 2021 Nov 01.
Article in English | MEDLINE | ID: mdl-34284327

ABSTRACT

Unknown illicit discharges from manufactories often contain toxic chemical matters that are detrimental to the receiving waterbody by deteriorating the performance of wastewater treatment plants. Numerical models that identify these sources and reconstruct the discharging profiles are highly desired for environment management purpose. In this study, a stochastic source identification model that couples Bayesian inference with SWMM is developed to reconstruct the profile of an instantaneous dumpling incidence in sewer networks. The unknown source parameters include location, dumping rate and time of the dumping incidence. Key factors that impact the convergence and performance of the model including walking step size, numbers of unknown source parameters and numbers of monitoring sites are investigated. Results show that the Bayesian-SWMM coupled model is effective and accurate in identifying the unknown sources parameters in an instantaneous dumping event. It is also found that walking step size is crucial for the results to converge to true solutions. Furthermore, it shows that the identified results are highly dependent on the numbers of unknown source parameters. More unknowns result to unsatisfying results. However, the study shows that this limitation could be significantly reduced by using more monitoring site data. One contribution of the study is that errors from measurements and numerical simulation are considered in the identification while results are presented in probabilities with all possible values revealed. This feature is highly practical and efficient when it comes to assist further field screening efforts to pinpoint the true sources.


Subject(s)
Bayes Theorem , Computer Simulation , Incidence , Probability
9.
Archaea ; 2018: 2148286, 2018.
Article in English | MEDLINE | ID: mdl-30245590

ABSTRACT

High salinity can strongly inhibit microbial activity and decrease the sedimentation ability of activated sludge. The combination of biofilm and membrane bioreactor is a practical approach towards effective removal of pollutants and low fouling rate. An integrated biofilm-membrane bioreactor (BMBR) treating mustard tuber wastewater was investigated. An average COD removal efficiency of 94.81% and ammonium removal efficiency of 96.84% were achieved at an organic load of 0.5 kg COD/(m3·d). However, the reactor showed a relatively low efficiency in total nitrogen and soluble phosphorus removal due to the lack of anaerobic environment. The increase of influent organic load resulted in a performance degradation because a balance between the degradation ability and pollution has been reached. Images of scanning electron microscopy revealed that halophilic bacteria were the dominant microbe in the system that leads to a loose sludge structure and declined settling properties. It was found that membrane fouling was the consequence of the interaction of microbial activities and NaCl crystallization.


Subject(s)
Biofilms/growth & development , Bioreactors/microbiology , Membranes , Organic Chemicals/metabolism , Salinity , Wastewater , Water Purification/methods , Aerobiosis , Ammonium Compounds/analysis , Anaerobiosis , Ascomycota , Bacteria/metabolism , Bacteria/ultrastructure , Biological Oxygen Demand Analysis , Metagenome , Microscopy, Electron, Scanning , Nitrogen/analysis , Phosphorus/analysis
10.
Se Pu ; 42(4): 352-359, 2024 Apr.
Article in Zh | MEDLINE | ID: mdl-38566424

ABSTRACT

Oxidative stress, which is characterized by an imbalance between antioxidants and free radicals, plays a pivotal role in the pathogenesis of coronary heart disease, a common and serious cardiovascular condition, and contributes significantly to its development and progression. Serum free thiols are crucial components of the body's antioxidant defense system. The accurate determination of serum free thiol levels provides a reference basis for understanding the body's status and monitoring the risk factors associated with the occurrence and progression of coronary heart disease. In this study, a high performance liquid chromatographic (HPLC) method based on the derivatization reaction of 2,2'-dithiodipyridine was developed to simultaneously obtain the concentrations of total free thiols (Total-SH), low-molecular-mass free thiols (LMM-SH), and protein-free thiols (P-SH) in human serum. An Agilent Eclipse XDB-C18 column (150 mm×4.6 mm, 5 µm) was used for the analysis, and gradient elution was performed at a flow rate of 1 mL/min. A 0.1% formic acid aqueous solution was used as mobile phase A, and a 0.1% formic acid acetonitrile solution was used as mobile phase B. The gradient elution program was as follows: 0-0.1 min, 12%B-30%B; 0.1-2 min, 30%B; 2-2.1 min, 30%B-100%B; 2.1-6 min, 100%B; 6-6.1 min, 100%B-12%B; 6.1-7 min, 12%B. Well-separated peaks appeared after a run time of 5 min. The peak of 2-thiopyridone represented the Total-SH content of the samples, and the peak of the pyridyldithio derivative represented the LMM-SH content. The difference between these two peaks indicated the P-SH content. The derivatization reaction conditions were optimized, and the method was validated. The method demonstrated good linearity, with a correlation coefficient ≥0.9994, over the concentration range of 31.25-1000 µmol/L. The limits of detection for Total-SH and LMM-SH were 2.61 and 0.50 µmol/L, and the limits of quantification for Total-SH and LMM-SH were 8.71 and 1.67 µmol/L, respectively. The recoveries of Total-SH and LMM-SH were in the range of 91.1%-106.0%. The intra- and inter-day precisions ranged from 0.4% to 9.1%. The developed method was used to analyze serum samples from 714 volunteers. The Total-SH concentrations ranged from 376.60 to 781.12 µmol/L, with an average concentration of 555.62 µmol/L. The LMM-SH concentrations varied from 36.37 to 231.65 µmol/L,with an average of 82.34 µmol/L. The P-SH concentrations ranged from 288.36 to 687.74 µmol/L, with an average of 473.27 µmol/L. Spearman's correlation test showed that serum thiol levels were correlated with the severity of coronary artery disease and common clinical biochemical indicators. The proposed study provides a simple and reliable HPLC method for detecting serum free thiols and exploring their relationship with coronary heart disease, offering a new reference for the study of markers related to the risk of coronary heart disease.


Subject(s)
2,2'-Dipyridyl/analogs & derivatives , Coronary Disease , Disulfides , Formates , Sulfhydryl Compounds , Humans , Chromatography, High Pressure Liquid , Antioxidants
11.
Zhongguo Zhen Jiu ; 44(3): 261-265, 2024 Mar 12.
Article in English, Zh | MEDLINE | ID: mdl-38467499

ABSTRACT

OBJECTIVES: To observe the clinical effect of the modified painless blistering moxibustion with wheat-grain sized moxa cone on cough variant asthma (CVA) differentiated as pathogenic wind attacking the lung and explore the influences on eosinophil count (EOS) in the peripheral blood and the content of interleukin-4 (IL-4) and tumor necrosis factor-α (TNF-α) in the serum of patients. METHODS: Ninety-two patients with CVA of pathogenic wind attacking the lung were randomly divided into an observation group and a control group, 46 cases in each group. In the observation group, the modified painless blistering moxibustion with wheat-grain sized moxa cone was applied to the unilateral Feishu (BL 13), Gaohuang (BL 43) and Zusanli (ST 36) in each session of treatment, once every 3 days. In the control group, budesonide and formoterol powder inhaler was delivered, 4.5 µg per inhalation, once every half an hour after breakfast and dinner; one more time of inhalation needed if the symptoms were not well controlled, but less than 6 times of inhalation per day. The duration of treatment was 8 weeks in both groups. Separately, before and after treatment, and during the 1-month follow-up after treatment completion, the score of the symptoms of traditional Chinese medicine (TCM) was observed in the two groups; using the lung function detector, the indexes of pulmonary function (forced expiratory volume in one second [FEV1], FEV1/forced vital capacity [FVC] and peak expiratory flow [PEF]) were determined, and the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum were determined before and after treatment; and the clinical effect was compared between the two groups. RESULTS: After treatment and in follow-up, the TCM symptom scores were decreased compared with those before treatment in the two groups (P<0.05), and the score in the observation group was lower than that of the control group in follow-up (P<0.05). After treatment, FEV1, FEV1/FVC and PEF were increased when compared with those before treatment in the two groups (P<0.05), and the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum were reduced (P<0.05); there was no statistical difference in these indexes between the two groups (P>0.05). After treatment, the total effective rate of the observation group was 95.7% (44/46), which was not different statistically in comparison with the control group (93.5% [43/46], P>0.05). In the follow-up, the total effective rate of the observation group was 95.7% (44/46), which was higher than that of the control group (78.3% [36/46], P<0.05). CONCLUSIONS: The modified painless blistering moxibustion with wheat-grain sized moxa cone may ameliorate the symptoms of CVA of pathogenic wind attacking the lung and improve the pulmonary functions, which is probably related to the regulation of the count of EOS in the peripheral blood and the content of IL-4 and TNF-α in the serum, thereby, reducing the inflammatory response.


Subject(s)
Cough-Variant Asthma , Moxibustion , Humans , Triticum , Interleukin-4 , Tumor Necrosis Factor-alpha , Wind , Lung
12.
Asian J Androl ; 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38856299

ABSTRACT

ABSTRACT: Male infertility is a global issue caused by poor sperm quality, particularly motility. Enhancement of the sperm quality may improve the fertilization rate in assisted reproductive technology (ART) treatment. Scriptaid, with a novel human sperm motility-stimulating activity, has been investigated as a prospective agent for improving sperm quality and fertilization rate in ART. We evaluated the effects of Scriptaid on asthenozoospermic (AZS) semen, including its impact on motility stimulation and protective effects on cryopreservation and duration of motility, by computer-aided sperm analysis (CASA). Sperm quality improvement by Scriptaid was characterized by increased hyaluronan-binding activity, tyrosine phosphorylation, adenosine triphosphate (ATP) concentration, mitochondrial membrane potential, and an ameliorated AZS fertilization rate in clinical intracytoplasmic sperm injection (ICSI) experiments. Furthermore, our identification of active Scriptaid analogs and different metabolites induced by Scriptaid in spermatozoa lays a solid foundation for the future biomechanical exploration of sperm function. In summary, Scriptaid is a potential candidate for the treatment of male infertility in vitro as it improves sperm quality, prolongs sperm viability, and increases the fertilization rate.

13.
Water Res ; 250: 121017, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38118254

ABSTRACT

Bioretention systems are one of the most widely used stormwater control measures for urban runoff treatment. However, stable and effective dissolved nutrient treatment by bioretention systems is often challenged by complicated stormwater conditions. In this study, pyrite-only (PO), pyrite-biochar (PB), pyrite-woodchip (PW), and pyrite-woodchip-biochar mixed (M) bioretention systems were established to study the feasibility of improving both stability and efficiency in bioretention system via multi-media interaction. PB, PW, and M all showed enhanced dissolved nitrogen and/or phosphorus removal compared to PO, with M demonstrating the highest efficiency and stability under different antecedent drying durations (ADD), pollutant levels, and prolonged precipitation depth. The total dissolved nitrogen and dissolved phosphorus removal in M ranged between 64%-86% and 80%-95%, respectively, with limited organic matter and iron leaching. Pore water, microbial community, and material analysis collectively indicate that pyrite, woodchip, and biochar synergistically facilitated multiple nutrient treatment processes and protected each other against by-product leaching. Pyrite-woodchip interaction greatly increased nitrate removal by facilitating mixotrophic denitrification, while biochar further enhanced ammonium adsorption and expanded the denitrification area. The Fe3+ generated by pyrite aerobic oxidation was adsorbed on the biochar surface and potentially formed a Fe-biochar composite layer, which not only reduced Fe3+-induced pyrite excessive oxidation but also potentially increased organic matter adsorption. Fe (oxyhydr)oxides intermediate product formed by pyrite oxidation, in return, controlled the phosphorus and organic matter leaching from biochar and woodchip. Overall, this study demonstrates that multi-media interaction may enable bioretention systems to achieve stable and effective urban runoff treatment.


Subject(s)
Charcoal , Iron , Nitrogen , Sulfides , Nitrogen/analysis , Phosphorus/analysis , Rain
14.
Planta Med ; 79(9): 792-6, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23670620

ABSTRACT

Three new xanthones, 22,23-dihydroxydihydrogambogenic acid (1), 12-hydroxygambogefic acid A (2), and hanburixanthone (3), along with thirteen known compounds were isolated from the resin of Garcinia hanburyi. The structures of the new compounds were determined by detailed analysis of 1D and 2D NMR spectra and by comparison with related model compounds. All compounds were tested for their cytotoxicities against A549, HCT116, and MDA-MB-231, and most of them showed significant effects on the cell lines.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Garcinia/chemistry , Resins, Plant/chemistry , Xanthones/chemistry , Xanthones/pharmacology , Antineoplastic Agents, Phytogenic/chemistry , Cell Line, Tumor , Drug Screening Assays, Antitumor , HCT116 Cells/drug effects , Humans , Magnetic Resonance Spectroscopy , Molecular Structure , Xanthones/analysis , Xanthones/isolation & purification
15.
Biomimetics (Basel) ; 8(1)2023 Feb 04.
Article in English | MEDLINE | ID: mdl-36810395

ABSTRACT

Studies have proven that humans perceive haptic textures through different perceptual dimensions, such as rough/smooth and soft/hard, which provide useful guidance in the design of haptic devices. However, few of these have focused on the perception of compliance, which is another important perceptual property in haptic interfaces. This research was conducted to investigate the potential basic perceptual dimensions of the rendered compliance and quantify the effects of the simulation parameters. Two perceptual experiments were designed based on 27 stimuli samples generated by a 3-DOF haptic feedback device. Subjects were asked to describe these stimuli using adjectives, classify the samples, and rate them according to corresponding adjective labels. Multi-dimensional scaling (MDS) methods were then used to project adjective ratings into 2D and 3D perception spaces. According to the results, hardness and viscosity are considered two basic perceptual dimensions of the rendered compliance, while crispness can be regarded as a subsidiary perceptual dimension. Then, the relations between simulation parameters and perceptual feelings were analyzed by the regression analysis. This paper may provide a better understanding of the compliance perception mechanism and useful guidance for the improvement of rendering algorithms and devices for haptic human-computer interaction.

16.
Se Pu ; 41(2): 131-141, 2023 Feb.
Article in Zh | MEDLINE | ID: mdl-36725709

ABSTRACT

Alcohol intake is an important risk factor for cardiovascular disease, liver disease, and diabetes. The accurate and objective evaluation of alcohol intake is important for disease prevention and intervention, as well as alcohol intake monitoring. Phosphatidylethanol (PEth) is a potential clinical biomarker of alcohol consumption. Monitoring PEth levels can provide an objective and quantitative basis for alcohol intake studies. Unlike other current alcohol biomarkers, PEth can only be produced in the presence of alcohol. Therefore, PEth is highly specific for alcohol intake and not affected by confounding factors, such as age, gender, hypertension, kidney disease, liver disease, and other comorbidities. Because of its long half-life and high specificity for alcohol intake, PEth may be used as a tool for monitoring drinking behavior in the clinical, transportation, and other fields. Given rapid developments in mass spectrometry technology over the past decade, liquid chromatography-tandem mass spectrometry (LC-MS/MS) has become the preferred method for PEth detection. However, most current LC-MS/MS methods focus on the determination of one or several PEth homologs, and the number of PEth homologs that can be determined simultaneously is relatively limited. Moreover, the detection capacity of the available methods remains insufficient, and their analytical sensitivity for some PEth homologs must be further improved. In this study, a novel LC-MS/MS method based on an intelligent scheduled time-zone negative multiple reaction monitoring acquisition technology (Scheduled-MRM) was developed. The technology monitors two ion channels in each PEth to ensure reliable results and can quantify 18 PEth homologs in human whole blood simultaneously. Methanol-methyl tert-butyl ether-water was used as the extraction system. An XBridge C18 column (100 mm×2.1 mm, 3.5 µm) was selected for gradient elution with 2.5 mmol/L ammonium acetate isopropanol solution and 2.5 mmol/L ammonium acetate aqueous solution-acetonitrile (50∶50, v/v) as the mobile phases. Negative electronic spray ionization in scheduled-MRM mode was applied for MS/MS detection. The method was validated to have a linear range of 10-2500 ng/mL with correlation coefficients greater than 0.9999. The limits of detection and quantification were 0.7-2.8 and 2.2-9.4 ng/mL, respectively, and the spiked recoveries ranged from 91.0% to 102.2%. The method was confirmed to be simple, rapid, and precise, and subsequently validated for the measurement of 18 PEth homologs in human blood. Scheduled-MRM can assign a suitable scan time to each ion channel and effectively reduce the number of concurrent ion pairs monitored per unit time. This technology overcomes the problem of insufficient dwell time caused by an excessive number of ion channels, thereby avoiding the redundant monitoring of non-retention times. Scheduled-MRM significantly improved the detection sensitivity, data acquisition quality, and signal response of the proposed method. Whole blood samples from 359 volunteers with regular drinking habits were analyzed using this method. The total PEth concentrations ranged from 51.13 ng/mL to 2.89 µg/mL, with a mean of 363.16 ng/mL. PEth 16∶0/18∶1 and 16∶0/18∶2 were the two most abundant homologs, with mean concentrations of 74.21 and 48.75 ng/mL, accounting for approximately 20.43% and 13.42%, respectively, of the total PEth. Spearman correlation analyses showed that the PEth homologs correlated well with each other, γ-glutamyltransferase, a clinically available biological marker of alcohol, and other clinical biochemical parameters related to liver and kidney function. Overall, the method was demonstrated to be sensitive, precise, and accurate; thus, it may be an effective tool for monitoring alcohol intake in the clinical and other fields.


Subject(s)
Ethanol , Tandem Mass Spectrometry , Humans , Chromatography, Liquid , Tandem Mass Spectrometry/methods , Technology , Biomarkers , Chromatography, High Pressure Liquid
17.
Chem Commun (Camb) ; 59(84): 12589-12592, 2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37791432

ABSTRACT

In this work, a Se-O bond is introduced by a simple oxidation method to realize the structural transformation from Cu2-xSe to Cu2O(SeO3) for enhanced electrocatalytic hydrogen evolution reaction (HER). The experiment and calculation results showed that Cu2O(SeO3) facilitated charge transfer and possessed a small barrier during the HER.

18.
Digit Health ; 9: 20552076221149528, 2023.
Article in English | MEDLINE | ID: mdl-36636727

ABSTRACT

Background: Thrombolysis is the first-line treatment for patients with acute ischemic stroke. Previous studies leveraged machine learning to assist neurologists in selecting patients who could benefit the most from thrombolysis. However, when designing the algorithm, most of the previous algorithms traded interpretability for predictive power, making the algorithms hard to be trusted by neurologists and be used in real clinical practice. Methods: Our proposed algorithm is an advanced version of classical k-nearest neighbors classification algorithm (KNN). We achieved high interpretability by changing the isotropy in feature space of classical KNN. We leveraged a cohort of 189 patients to prove that our algorithm maintains the interpretability of previous models while in the meantime improving the predictive power when compared with the existing algorithms. The predictive powers of models were assessed by area under the receiver operating characteristic curve (AUC). Results: In terms of interpretability, only onset time, diabetes, and baseline National Institutes of Health Stroke Scale (NIHSS) were statistically significant and their contributions to the final prediction were forced to be proportional to their feature importance values by the rescaling formula we defined. In terms of predictive power, our advanced KNN (AUC 0.88) outperformed the classical KNN (AUC 0.75, p = 0.0192 ). Conclusions: Our preliminary results show that the advanced KNN achieved high AUC and identified consistent significant clinical features as previous clinical trials/observational studies did. This model shows the potential to assist in thrombolysis patient selection for improving the successful rate of thrombolysis.

19.
Sci Total Environ ; 887: 164130, 2023 Aug 20.
Article in English | MEDLINE | ID: mdl-37182783

ABSTRACT

Simultaneous nitrogen and phosphorus removal (SNPR) biofilm system is an effective wastewater treatment process. However, the understanding on the mechanism of functional microorganisms driving SNPR is still limited, especially the role of complete ammonia oxidation (comammox) Nitrospira and glycogen-accumulating organisms (GAO). In this study, a sequencing batch biofilm reactor (SBBR) performing SNPR was operated for 249 d. Based on the 16S rRNA gene, comammox amoA amplicon sequencing, metagenomics and batch experiment, we found that comammox Nitrospira was the main ammonia-oxidizing microorganisms (AOM) and provided nitrite for anaerobic ammonia oxidation (anammox) bacteria (AnAOB). Besides, GAO was dominated by the bacteria of genus Defluviicoccus and played a primary role in reducing nitrate rather than nitrite. Fluorescent in situ hybridization (FISH) analysis confirmed that Nitrospira was enriched in the inner layer of the biofilm. Thus, we put forward a novel insight into the mechanism of SNPR biofilm system. Comammox Nitrospira was responsible for nitrite and nitrate production in the inner biofilm, and AnAOB consumed the produced nitrite during the anammox process. While GAO reduced nitrate to nitrite and polyphosphate-accumulating organisms (PAO) converted nitrite to dinitrogen via denitrifying phosphorus removal in the outer biofilm. These findings provide a new understanding in SNPR biofilm system.


Subject(s)
Ammonia , Nitrogen , Nitrites , Nitrates , Nitrification , Phosphorus , RNA, Ribosomal, 16S/genetics , In Situ Hybridization, Fluorescence , Oxidation-Reduction , Bacteria , Biofilms , Bioreactors/microbiology
20.
Nanoscale Adv ; 5(9): 2418-2421, 2023 May 02.
Article in English | MEDLINE | ID: mdl-37143792

ABSTRACT

Herein, we report the method of molecular-beam-epitaxial growth (MBE) for precisely regulating the terminal surface with different exposed atoms on indium telluride (InTe) and studied the electrocatalytic performances toward hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). The improved performances result from the exposed In or Te atoms cluster, which affects the conductivity and active sites. This work provides insights into the comprehensive electrochemical attributes of layered indium chalcogenides and exhibits a new route for catalyst synthesis.

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