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1.
Anal Chem ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749062

RESUMO

Solid contact (SC) calcium ion-selective electrodes (Ca2+-ISEs) have been widely applied in the analysis of water quality and body fluids by virtue of the unique advantages of easy operation and rapid response. However, the potential drift during the long-term stability test hinders their further practical applications. Designing novel redox SC layers with large capacitance and high hydrophobicity is a promising approach to stabilize the potential stability, meanwhile, exploring the transduction mechanism is also of great guiding significance for the precise design of SC layer materials. Herein, flower-like copper sulfide (CunS-50) composed of nanosheets is meticulously designed as the redox SC layer by modification with the surfactant (CTAB). The CunS-50-based Ca2+-ISE (CunS-50/Ca2+-ISE) demonstrates a near-Nernstian slope of 28.23 mV/dec for Ca2+ in a wide activity linear range of 10-7 to 10-1 M, with a low detection limit of 3.16 × 10-8 M. CunS-50/Ca2+-ISE possesses an extremely low potential drift of only 1.23 ± 0.13 µV/h in the long-term potential stability test. Notably, X-ray absorption fine-structure (XAFS) spectra and electrochemical experiments are adopted to elucidate the transduction mechanism that the lipophilic anion (TFPB-) participates in the redox reaction of CunS-50 at the solid-solid interface of ion-selective membrane (ISM) and redox inorganic SC layer (CunS-50), thereby promoting the generation of free electrons to accelerate ion-electron transduction. This work provides an in-depth comprehension of the transduction mechanism of the potentiometric response and an effective strategy for designing redox materials of ion-electron transduction triggered by lipophilic anions.

2.
ACS Nano ; 18(20): 12808-12819, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38717026

RESUMO

Considerable progress has already been made in sweat sensors based on electrochemical methods to realize real-time monitoring of biomarkers. However, realizing long-term monitoring of multiple targets at the atomic level remains extremely challenging, in terms of designing stable solid contact (SC) interfaces and fully integrating multiple modules for large-scale applications of sweat sensors. Herein, a fully integrated wristwatch was designed using mass-manufactured sensor arrays based on hierarchical multilayer-pore cross-linked N-doped porous carbon coated by reduced graphene oxide (NPCs@rGO-950) microspheres with high hydrophobicity as core SC, and highly selective monitoring simultaneously for K+, Na+, and Ca2+ ions in human sweat was achieved, exhibiting near-Nernst responses almost without forming an interfacial water layer. Combined with computed tomography, solid-solid interface potential diffusion simulation results reveal extremely low interface diffusion potential and high interface capacitance (598 µF), ensuring the excellent potential stability, reversibility, repeatability, and selectivity of sensor arrays. The developed highly integrated-multiplexed wristwatch with multiple modules, including SC, sensor array, microfluidic chip, signal transduction, signal processing, and data visualization, achieved reliable real-time monitoring for K+, Na+, and Ca2+ ion concentrations in sweat. Ingenious material design, scalable sensor fabrication, and electrical integration of multimodule wearables lay the foundation for developing reliable sweat-sensing systems for health monitoring.


Assuntos
Eletrólitos , Grafite , Suor , Dispositivos Eletrônicos Vestíveis , Suor/química , Humanos , Grafite/química , Eletrólitos/química , Íons/análise , Cálcio/análise , Sódio/análise , Sódio/química , Técnicas Biossensoriais/instrumentação , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/métodos , Potássio/análise
3.
Anal Chim Acta ; 1306: 342612, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38692793

RESUMO

Despite the widespread utilization of variable valence metals in electrochemistry, it is still a formidable challenge to enhance the valence conversion efficiency to achieve excellent catalytic activity without introducing heterophase elements. Herein, the in-situ precipitation of Co particles on Co2VO4 not only enhanced the concentration of oxygen vacancies (Ov) but also generated a greater number of low-valence metals, thereby enabling efficient reduction towards Hg(II). The electroanalysis results demonstrate that the sensitivity of Co/Co2VO4 towards Hg(II) was measured at an impressive value of 1987.74 µA µM-1 cm-2, significantly surpassing previously reported results. Further research reveals that Ov acted as the main adsorption site to capture Hg(II). The redox reactions of Co2+/Co3+ and V3+/V4+ played a synergistic role in the reduction of Hg(II), accompanied by the continuous supply of electrons from zero-valent Co to expedite the valence cycle. The Co/Co2VO4/GCE presented remarkable selectivity towards Hg(II), with excellent stability, reproducibility, and anti-interference capability. The electrode also exhibited minimal sensitivity fluctuations towards Hg(II) in real water samples, underscoring its practicality for environmental applications. This study elucidates the mechanism underlying the surface redox reaction of metal oxides facilitated by zero-valent metals, providing us with new strategies for further design of efficient and practical sensors.

4.
Anal Chem ; 96(13): 5232-5241, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38447030

RESUMO

Although utilizing nanomaterial-modified electrodes for lead ion detection has achieved great success, most of them are carried out under acidic conditions and ignore the variation of Pb(II) speciation at different pH conditions, leading to the potential inaccuracy of Pb(II) detection in a neutral natural water environment. Thus, designing a novel catalyst with high accuracy for the detection of various forms of the total amount of Pb(II) (Pb2+ and Pb(OH)+) in neutral waters is significant. Herein, Pt nanoclusters (Pt NCs) were elaborately constructed and stabilized on the Co single-atom-doped g-C3N4 with abundant N vacancies (Pt NCs/VN-C3N4), which achieved the ultrasensitive detection (102.16 µM µA-1) of Pb(II) in neutral conditions. The dynamic simulation and theoretical calculations reveal that the parallel deposition of Pb2+ and Pb(OH)+ occurs on the electrode surface modified by Pt NCs/VN-C3N4, and the current peaks of Pb(II) are cocontributed by Pb2+ and Pb(OH)+ species. An "electron inverse" phenomenon in Pt NCs/VN-C3N4 from the VN-C3N4 substrate to Pt NCs endows Pt NCs in an electron-rich state, serving as active centers to promote rapid and efficient reduction for both Pb2+ and Pb(OH)+, facilitating the accurate detection of the total amount of Pb(II) in all forms in the actual water environment.

5.
Ann Plast Surg ; 92(1S Suppl 1): S27-S32, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38285992

RESUMO

BACKGROUND: Patients with traumatic brain injuries (TBIs) often experience concurrent facial bone fractures. In 2021, a prediction model with 10 variables was published and precisely predicted concomitant facial fractures in TBI patients. Herein, external validation and simplification of this model was performed. METHODS: Traumatic brain injury patients treated at a major referral trauma center were retrospectively reviewed for 1 year. The original prediction model (published in 2021), which was developed from a rural level II trauma center, was applied for external validation. A new and simplified model from our level I trauma center was developed and backwardly validated by rural level II trauma center data. RESULTS: In total, 313 TBI patients were enrolled; 101 (32.3%) had concomitant facial fractures. When the previous prediction model was applied to the validation cohort, it achieved acceptable discrimination, with an area under the receiver operating characteristic curve (AUC) of 0.713 and good precision, with a Brier score of 0.083. A new and simplified model with 6 variables (age, tooth rupture, epistaxis, facial lesion, eye injury, and intracranial hemorrhage) was created with excellent discrimination (AUC = 0.836) and good precision (Brier score of 0.055). The backward validation of this new model also showed excellent discrimination in the cohort used to develop the original model (AUC = 0.875). CONCLUSION: The original model provides an acceptable and reproducible prediction of concomitant facial fractures among TBI patients. A simplified model with fewer variables and the same accuracy could be applied in the emergency department and at higher- and lower-level trauma centers.


Assuntos
Lesões Encefálicas Traumáticas , Fraturas Cranianas , Humanos , Estudos Retrospectivos , Fraturas Cranianas/complicações , Fraturas Cranianas/diagnóstico , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Curva ROC , Centros de Traumatologia
6.
Zool Res ; 45(1): 39-54, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38114432

RESUMO

The dynamics of animal social structures are heavily influenced by environmental patterns of competition and cooperation. In folivorous colobine primates, prevailing theories suggest that larger group sizes should be favored in rainforests with a year-round abundance of food, thereby reducing feeding competition. Yet, paradoxically, larger groups are frequently found in high-altitude or high-latitude montane ecosystems characterized by a seasonal scarcity of leaves. This contradiction is posited to arise from cooperative benefits in heterogeneous environments. To investigate this hypothesis, we carried out a six-year field study on two neighboring groups of golden snub-nosed monkey ( Rhinopithecus roxellana), a species representing the northernmost distribution of colobine primates. Results showed that the groups adjusted their movement and habitat selection in response to fluctuating climates and spatiotemporal variability of resources, indicative of a dynamic foraging strategy. Notably, during the cold, resource-scarce conditions in winter, the large group occupied food-rich habitats but did not exhibit significantly longer daily travel distances than the smaller neighboring group. Subsequently, we compiled an eco-behavioral dataset of 52 colobine species to explore their evolutionary trajectories. Analysis of this dataset suggested that the increase in group size may have evolved via home range expansion in response to the cold and heterogeneous climates found at higher altitudes or latitudes. Hence, we developed a multi-benefits framework to interpret the formation of larger groups by integrating environmental heterogeneity. In cold and diverse environments, even smaller groups require larger home ranges to meet their dynamic survival needs. The spatiotemporal distribution of high-quality resources within these expanded home ranges facilitates more frequent interactions between groups, thereby encouraging social aggregation into larger groups. This process enhances the benefits of collaborative actions and reproductive opportunities, while simultaneously optimizing travel costs through a dynamic foraging strategy.


Assuntos
Colobinae , Presbytini , Animais , Ecossistema , Colobinae/fisiologia , Clima , China
7.
ACS Sens ; 9(1): 415-423, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38154098

RESUMO

The high selectivity and fast ion response of all-solid sodium ion selective electrodes were widely applied in human sweat analysis. However, the potential drift due to insufficient interfacial capacitance leads to the deterioration of its stability and ultimately affects the potential accuracy of ion analysis. Designing a novel ion-electron transduction layer between the electrode and the ion selective membrane is an effective method to stabilize the interfacial potential. Herein, the SnS2-MoS2 heterojunction material was constructed by doping Sn in MoS2 nanosheets and used as the ion electron transduction layers of an all-solid sodium ion selective electrode for the first time, achieving the stable and efficient detection of Na+ ions. The proposed electrode exhibited a Nernst slope of 57.86 mV/dec for the detection of Na+ ions with a detection limit of 10-5.7 M in the activity range of 10-6-10-1 M. Via the electronic interaction at the heterojunction interfaces between SnS2 and MoS2 materials, the micro-nanostructure of the SnS2-MoS2 heterojunction was changed and SnS2-MoS2 as the ion-electron transduction layer acquired excellent capacitance (699 µF) and hydrophobicity (132°), resulting in a long-term potential stability of 1.37 µV/h. It was further proved that the large capacitance and high hydrophobicity of the ion-electron transduction layer are primary reasons for the excellent stability of the all-solid sodium ion selective electrode toward Na+ ions.


Assuntos
Eletrodos Seletivos de Íons , Molibdênio , Humanos , Elétrons , Capacitância Elétrica , Íons
8.
Anal Chem ; 96(1): 179-187, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38100653

RESUMO

Achieving accurate detection of different speciations of heavy metal ions (HMIs) in an aqueous solution is an urgent problem due to the different bioavailabilities and physiological toxicity. Herein, we nominated a novel strategy to detect HCrO4- and Cr(OH)2+ at a trace level via the electrochemical sensitive surface constructed by Co3O4-rGO modified with amino and carboxyl groups, which revealed that the interactions between distinct functional groups and different oxygen-containing groups of target ions are conducive to the susceptible and anti-interference detection. The detection sensitivities of 19.46 counts µg-1 L for HCrO4- and 13.44 counts µg-1 L for Cr(OH)2+ were obtained under optimal conditions, while the limits of detection were 0.10 and 0.12 µg L-1, respectively. Satisfactory anti-interference and actual water sample analysis results were obtained. A series of advanced optical techniques like X-ray photoelectron spectroscopy, X-ray absorption near-edge structure technology, and density functional theory calculations under an electric field demonstrated that chemical interactions between groups contribute more to the fixation of target ions than electrical attraction alone. The presence of oxygen-containing groups distinct from simple ionic forms was a critical factor in the selectivity and anti-interference detection. Furthermore, the valence cycle of Co(II)/(III) synergistically boosted the detection performance. This research provides a promising tactic from the microscopic perspective of groups' interactions to accomplish the precise speciation analysis of HMIs in the water environment.

9.
World J Surg ; 47(12): 3116-3123, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37851065

RESUMO

PURPOSE: This study aimed to validate the previously reported association between delayed bladder repair and increased infection rates using the National Trauma Data Bank (NTDB). METHODS: Bladder injury patients with bladder repair in the NTDB from 2013 to 2015 were included. Propensity score matching (PSM) was used to compare mortality, infection rates, and hospital length of stay (LOS) between patients who underwent bladder repair within 24 h and those who underwent repair after 24 h. Linear regression and multivariate logistic regression analyses were also performed. RESULTS: A total of 1658 patients were included in the study. Patients who underwent bladder repair after 24 h had significantly higher infection rates (5.4% vs. 1.2%, p = 0.032) and longer hospital LOS (17.1 vs. 14.0 days, p = 0.032) compared to those who underwent repair within 24 h after a well-balanced 1:1 PSM (N = 166). Linear regression analysis showed a positive correlation between time to bladder repair and hospital LOS for patients who underwent repair after 24 h (B-value = 0.093, p = 0.034). Multivariate logistic regression analysis indicated that bladder repair after 24 h increased the risk of infection (odds = 3.162, p = 0.018). Subset analyses were performed on patients who underwent bladder repairs within 24 h and were used as a control group. These analyses showed that the time to bladder repair did not significantly worsen outcomes. CONCLUSIONS: Delayed bladder repair beyond 24 h increases the risk of infection and prolongs hospital stays. Timely diagnosis and surgical intervention remain crucial for minimizing complications in bladder injury patients.


Assuntos
Traumatismos Abdominais , Traumatismos Torácicos , Humanos , Bexiga Urinária/cirurgia , Tempo de Internação , Procedimentos Cirúrgicos Urológicos , Resultado do Tratamento , Estudos Retrospectivos
10.
Chem Sci ; 14(36): 9678-9688, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37736653

RESUMO

Single-atom catalysts have been extensively utilized for electrocatalysis, in which electronic metal-support interactions are typically employed to stabilize single atoms. However, this neglects the metal-metal interactions of adjacent atoms, which are essential for the fine-tuning of selective sites. Herein, the high-loading of Ir single atoms (Ir SAs) (8.9 wt%) were adjacently accommodated into oxygen vacancy-rich Co3O4 nanosheets (Ir SAs/Co3O4). Electronic perturbations for both Ir single atoms and Co3O4 supports were observed under electronic metal-support and metal-metal interactions, thus generating Ir-O-Co/Ir units. Electrons were transferred from Co and Ir to O atoms, inducing the depletion of 3d/5d states in Co/Ir and the occupation of 2p states in O atoms to stabilize the Ir SAs. Moreover, the O atoms of Ir-O-Ir functioned as the main active sites for the electrocatalysis of As(iii), which reduced the energy barrier for the rate-determining step. This was due to the stronger electronic affinities for intermediates from reduction of As(iii), which were completely distinct from other coordinated O atoms of Co3O4 or IrO2. Consequently, the resultant Ir SAs/Co3O4 exhibited far more robust electrocatalytic activities than IrO2/Co3O4 and Co3O4 in the electrocatalysis of As(iii). Moreover, there was a strong orbital coupling effect between the coordinated O atoms of Ir SAs and the -OH of H3AsO3, thus exhibiting superior selectivity for As(iii) in contrast to other common heavy metal cations. This work offers useful insights into the rational design of intriguing SACs with high selectivity and stability for the electrocatalysis and electrochemical analysis of pollutants on an electronic level.

11.
Anal Chim Acta ; 1277: 341676, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37604614

RESUMO

The mutual interference in the sensing detection of heavy metal ions (HMIs) is considerably serious and complex. Besides, the co-existed ions may change the stripping peak intensity, shape and position of the target ion, which partly makes peak current analysis inaccurate. Herein, a promising approach of partial peak area analysis was proposed firstly to research the mutual interference. The interference between two species on their electrodeposition processes was investigated by simulating different kinetics parameters, including surface coverage, electro-adsorption, -desorption rate constant, etc. It was proved that the partial peak area is sensitive and regular to these interference kinetics parameters, which is favorable for distinctly identifying different interferences. Moreover, the applicability of the partial peak area analysis was verified on the experiments of Cu2+, As(III) interference at four sensing interfaces: glassy carbon electrode, gold electrode, Co3O4, and Fe2O3 nanoparticles modified electrodes. The interference behaviors between Cu2+ and As(III) relying on solid-solution interfaces were revealed and confirmed by physicochemical characterizations and kinetics simulations. This work proposes a new descriptor (partial peak area) to recognize the interference mechanism and provides a meaningful guidance for accurate detection of HMIs in actual water environment.

12.
J Hazard Mater ; 459: 132104, 2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37490798

RESUMO

The perplexity of double peaks in Pb(II) detections has been a threat to the reliability of Pb(II) electroanalysis results for a long term. For the complexity of electrode interfaces, rare studies were taken on mechanisms of Pb(II) double peaks through interfacial kinetics. In this work, analyses on experimental signals and interfacial simulations were working together to reveal that the generation of Pb(II) double peaks in Pb(II)-Cu(II) systems is the deposition of Pb(II) on Cu deposits occurring in parallel. By applying anode stripping voltammetry and cyclic voltammetry, a parallel deposition reaction was found to influence the shape of Pb(II) peaks, and the existence of the second peak was controlled through the adjustment of experimental conditions. A kinetic model was built to reveal the interference of electroanalysis signals caused by a parallel deposition reaction and simulations based on the model were combined with experiments to illustrate that double peaks of Pb(II) were caused by the parallel deposition on Cu(II) deposits. This work proposes another insight of Pb(II) double peaks from macroscale kinetics and pays more attention on the dynamic procedure of electroanalysis interfaces, which makes the study on environmental electroanalysis interface phenomena more clear and is enlightening to develop efficient electrical methods for pollutant monitoring.

13.
Chem Sci ; 14(11): 2960-2970, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36937602

RESUMO

Although the enhanced intrinsic activities of some nano-metal oxides are obtained by manufacturing oxygen vacancies (OVs), the effect of multiple roles of OVs is ambiguous. Herein, an interface catalytic regulation via electron rearrangement and hydroxyl radicals (˙OH) was proposed with the designed ZrO2 hollow sphere rich in OVs (Vo-rich ZrO2). Surprisingly, it was shown that the catalytic ability of Vo-rich ZrO2 was 9.9 times higher than that of ZrO2 with little OVs in electrochemical catalytic reduction of Pb(ii). It was found that the generation of Zr2+ and Zr3+ caused by OVs results in the rearrangement of abundant free electrons to facilitate the catalytic reaction rates. The longer bond length between Vo-rich ZrO2 and reactants, and the lower adsorption energy are beneficial for reactants to desorb, improving the conversion rates. Besides, the produced ˙OH were captured which were induced by OVs and trace divalent heavy metal ions in in situ electron paramagnetic resonance (EPR) experiments, contributing to lowering the energy barriers. This study not only revealed the enhanced interface catalytic effect of electron rearrangement and generated ˙OH triggered by OVs, but also provided unique insights into interface catalytic regulation on nano-metal oxides simulated by OVs.

14.
Surgery ; 173(5): 1296-1302, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36759210

RESUMO

BACKGROUND: The appropriate timing of surgical intervention for bladder injuries is not well-defined. The effect of time to surgery on the outcomes of patients with a bladder injury was assessed using data from the Trauma Quality Improvement Program. METHODS: Patients with dominant or isolated bladder injuries who underwent surgical repair from 2017 to 2019 were studied. Mortality, infection (surgical site infection or sepsis), acute kidney injury, overall length of stay, and length of stay after surgery were compared between patients who underwent bladder repair within and after 24 hours of arrival at the emergency department. The role of time to surgical repair in the outcomes of patients with a bladder injury was evaluated. RESULTS: A total of 1,507 patients with a mean time to bladder repair of 14.0 hours were studied. In total, 233 (15.5%) patients with a bladder injury underwent bladder repair more than 1 day after emergency department arrival. These patients had significantly more infections (5.6% vs 2.5%, P = .011), more acute kidney injuries (7.8% vs 1.8%, P < .001), and a longer length of stay after surgery (16.0 vs 12.3 days, P = .001) than patients who underwent bladder repair within 1 day. A time to bladder repair longer than 24 hours after emergency department arrival did not significantly affect mortality (P = .075) but significantly increased the risk of infection/acute kidney injury (odds = 1.823, P = .040). However, the infection/acute kidney injury risk did not increase with increasing time to surgery in patients who underwent bladder repair within 24 hours (P = .120). CONCLUSION: Patients with dominant or isolated bladder injuries may have a poor outcome (ie, increased infection rate, acute kidney injury, longer overall length of stay, and longer length of stay after bladder repair) if they undergo surgical repair more than 24 hours after arrival at the emergency department.


Assuntos
Traumatismos Abdominais , Traumatismos Torácicos , Humanos , Bexiga Urinária/cirurgia , Melhoria de Qualidade , Procedimentos Cirúrgicos Urológicos/efeitos adversos , Serviço Hospitalar de Emergência , Estudos Retrospectivos , Tempo de Internação
15.
Anal Chem ; 95(7): 3666-3674, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36656141

RESUMO

Traditional nanomodified electrodes have made great achievements in electrochemical stripping voltammetry of sensing materials for As(III) detection. Moreover, the intermediate states are complicated to probe because of the ultrashort lifetime and complex reaction conditions of the electron transfer process in electroanalysis, which seriously hinder the identification of the actual active site. Herein, the intrinsic interaction of highly sensitive analytical behavior of nanomaterials is elucidated from the perspective of electronic structure through density functional theory (DFT) and gradient boosting regression (GBR). It is revealed that the atomic radius, d-band center (εd), and the largest coordinative TM-N bond length play a crucial role in regulating the arsenic reduction reaction (ARR) performance by the established ARR process for 27 sets of transition-metal single atoms supported on N-doped graphene. Furthermore, the database composed of filtered intrinsic electronic structural properties and the calculated descriptors of the central metal atom in TM-N4-Gra were also successfully extended to oxygen evolution reaction (OER) systems, which effectively verified the reliability of the whole approach. Generally, a multistep workflow is developed through GBR models combined with DFT for valid screening of sensing materials, which will effectively upgrade the traditional trial-and-error mode for electrochemical interface designing.

16.
Anal Chem ; 95(8): 4104-4112, 2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36688529

RESUMO

Significant progress has been made in nanomaterial-modified electrodes for highly efficient electroanalysis of arsenic(III) (As(III)). However, the modifiers prepared using some physical methods may easily fall off, and active sites are not uniform, causing the potential instability of the modified electrode. This work first reports a promising practical strategy without any modifiers via utilizing only soluble Fe3+ as a trigger to detect trace-level As(III) in natural water. This method reaches an actual detection limit of 1 ppb on bare glassy carbon electrodes and a sensitivity of 0.296 µA ppb-1 with excellent stability. Kinetic simulations and experimental evidence confirm the codeposition mechanism that Fe3+ is preferentially deposited as Fe0, which are active sites to adsorb As(III) and H+ on the electrode surface. This facilitates the formation of AsH3, which could further react with Fe2+ to produce more As0 and Fe0. Meanwhile, the produced Fe0 can also accelerate the efficient enrichment of As0. Remarkably, the proposed sensing mechanism is a general rule for the electroanalysis of As(III) that is triggered by iron group ions (Fe2+, Fe3+, Co2+, and Ni2+). The interference analysis of coexisting ions (Cu2+, Zn2+, Al3+, Hg2+, Cd2+, Pb2+, SO42-, NO3-, Cl-, and F-) indicates that only Cu2+, Pb2+, and F- showed inhibitory effects on As(III) due to the competition of active sites. Surprisingly, adding iron power effectively eliminates the interference of Cu2+ in natural water, achieving a higher sensitivity for 1-15 ppb As(III) (0.487 µA ppb-1). This study provides effective solutions to overcome the potential instability of modified electrodes and offers a practical sensing platform for analyzing other heavy-metal anions.

17.
J Hazard Mater ; 442: 130122, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36303353

RESUMO

Mutual interference issues between heavy metal ions tremendously affect the detection reliability and accuracy in water quality analysis, especially the serious interference of Cu(II) on the detection of As(III) is greatly hard to overcome, which needs to be solved urgently. Herein, iron single-atom catalysts with different coordination structures of FeN2C2 and FeN3P are constructed to selectively catalyze the detection of As(III) in the coexistence of Cu(II). FeN3P achieves a high sensitivity of 3.90 µA ppb-1 toward As(III) in NH4Cl/NH3·H2O electrolyte (pH 8.0), completely avoiding Cu(II)-interference. Moreover, the turnover frequency (TOF) of FeN3P is an order of magnitude higher than that of FeN2C2. X-ray absorption fine structure (XAFS) spectroscopy and density functional theory (DFT) calculations demonstrate that an As-O bond of H3AsO3 is broken by the strong affinities between both P and O atoms and Fe and As atoms, and H3AsO3 are preferentially reduced by FeN3P during adsorptive process. Meanwhile, the low reaction energy barrier of the rate-determined step for As(III) reduction over FeN3P also accelerates the deposition of As(III) and enhances its response signals. The free-Cu(II) are difficult to adsorb on FeN3P and do not compete with As(III) for Fe active sites, which contributes to the excellent anti-Cu(II) interference capability.

18.
Anal Chem ; 94(40): 13631-13641, 2022 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-36150119

RESUMO

Constructing high-effective electrode sensing interfaces has been considered an effective method for electrochemical detection toward heavy metal ions (HMIs). However, most research has been devoted to enhancing the stripping currents of HMIs by simply improving the adsorptive capacity and conductivity of the electrode modified materials, while lacking theoretical guidelines in fabricating catalytic sensing interfaces. Besides, the understanding of detection mechanisms is quite unscientific from the perspective of catalysis. This perspective summarizes five general strategies in designing highly efficient sensing interfaces in the recent five years, including modulating crystal phases, orientations and planes, defect engineering, ionic valence state cycle engineering, adsorption in situ catalysis strategy, and construction of atomic level catalytic active sites. What's more, the catalytic mechanisms for improving the signals of HMIs, such as boosting the electron transfer rates and conversion rates, lowering the energy barriers, etc., are introduced and emphasized. This study has a great significance in directionally controlling functionalized electrochemical sensors to achieve excellent sensitivity and selectivity in detecting environmental pollutants from the view of catalysis, and it also brings enlightenments and guidance to develop new electroanalytical methods.


Assuntos
Poluentes Ambientais , Metais Pesados , Catálise , Eletrodos , Íons/química , Metais Pesados/química
19.
Infect Dis Model ; 7(2): 127-137, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35573860

RESUMO

Objective: Mumps is a seasonal infectious disease, always occurring in winter and spring. In this study, we aim to analyze its epidemiological characteristics, transmissibility, and its correlation with meteorological variables. Method: A seasonal Susceptible-Exposed-Infectious/Asymptomatic-Recovered model and a next-generation matrix method were applied to estimate the time-dependent reproduction number (R t ). Results: The seasonal double peak of annual incidence was mainly in May to July and November to December. There was high transmission at the median of R t  = 1.091 (ranged: 0 to 4.393). R t was seasonally distributed mainly from February to April and from September to November. Correlations were found between temperature (Pearson correlation coefficient [r] ranged: from 0.101 to 0.115), average relative humidity (r = 0.070), average local pressure (r = -0.066), and the number of new cases. In addition, average local pressure (r = 0.188), average wind speed (r = 0.111), air temperature (r ranged: -0.128 to -0.150), average relative humidity (r = -0.203) and sunshine duration (r = -0.075) were all correlated with R t . Conclusion: A relatively high level of transmissibility has been found in Xiamen City, leading to a continuous epidemic of mumps. Meteorological factors, especially air temperature and relative humidity, may be more closely associated with mumps than other factors.

20.
World J Emerg Surg ; 17(1): 29, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624457

RESUMO

BACKGROUND: Open pelvic fractures are rare but complex injuries. Concomitant external and internal hemorrhage and wound infection-related sepsis result in a high mortality rate and treatment challenges. Here, we validated the World Society Emergency Society (WSES) classification system for pelvic injuries in open pelvic fractures, which are quite different from closed fractures, using the National Trauma Data Bank (NTDB). METHODS: Open pelvic fracture patients in the NTDB 2015 dataset were retrospectively queried. The mortality rates associated with WSES minor, moderate and severe injuries were compared. A multivariate logistic regression model (MLR) was used to evaluate independent factors of mortality. Patients with and without sepsis were compared. The performance of the WSES classification in the prediction of mortality was evaluated by determining the discrimination and calibration. RESULTS: A total of 830 open pelvic fracture patients were studied. The mortality rates of the mild, moderate and severe WSES classes were 3.5%, 11.2% and 23.8%, respectively (p < 0.001). The MLR analysis showed that the presence of sepsis was an independent factor of mortality (odds of mortality 9.740, p < 0.001). Compared with patients without sepsis, those with sepsis had significantly higher mortality rates in all WSES classes (minor: 40.0% vs. 3.1%, p < 0.001; moderate: 50.0% vs. 9.1%, p < 0.001; severe: 66.7% vs. 22.2%, p < 0.001). The receiver operating characteristic (ROC) curve showed an acceptable discrimination of the WSES classification alone for evaluating the mortality of open pelvic fracture patients [area under curve (AUC) = 0.717]. Improved discrimination with an increased AUC was observed using the WSES classification plus sepsis (AUC = 0.767). CONCLUSIONS: The WSES guidelines can be applied to evaluate patients with open pelvic fracture with accurate evaluation of outcomes. The presence of sepsis is recommended as a supplement to the WSES classification for open pelvic fractures.


Assuntos
Fraturas Expostas , Ossos Pélvicos , Sepse , Humanos , Ossos Pélvicos/lesões , Pelve , Estudos Retrospectivos
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