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1.
Proc Natl Acad Sci U S A ; 120(48): e2314362120, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37983507

RESUMO

Interfacial catalysis occurs ubiquitously in electrochemical systems, such as batteries, fuel cells, and photocatalytic devices. Frequently, in such a system, the electrode material evolves dynamically at different operating voltages, and this electrochemically driven transformation usually dictates the catalytic reactivity of the material and ultimately the electrochemical performance of the device. Despite the importance of the process, comprehension of the underlying structural and compositional evolutions of the electrode material with direct visualization and quantification is still a significant challenge. In this work, we demonstrate a protocol for studying the dynamic evolution of the electrode material under electrochemical processes by integrating microscopic and spectroscopic analyses, operando magnetometry techniques, and density functional theory calculations. The presented methodology provides a real-time picture of the chemical, physical, and electronic structures of the material and its link to the electrochemical performance. Using Co(OH)2 as a prototype battery electrode and by monitoring the Co metal center under different applied voltages, we show that before a well-known catalytic reaction proceeds, an interfacial storage process occurs at the metallic Co nanoparticles/LiOH interface due to injection of spin-polarized electrons. Subsequently, the metallic Co nanoparticles act as catalytic activation centers and promote LiOH decomposition by transferring these interfacially residing electrons. Most intriguingly, at the LiOH decomposition potential, electronic structure of the metallic Co nanoparticles involving spin-polarized electrons transfer has been shown to exhibit a dynamic variation. This work illustrates a viable approach to access key information inside interfacial catalytic processes and provides useful insights in controlling complex interfaces for wide-ranging electrochemical systems.

2.
Lipids Health Dis ; 23(1): 7, 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38185678

RESUMO

BACKGROUND: The relation of adipose tissue depletion with prognostic outcome of variceal bleeding among cirrhotic patients is still inconclusive. The present work explored whether adipose tissue, which was measured based on computed tomography (CT), was valuable for analyzing rebleeding and mortality among patients with variceal bleeding who had undergone endoscopic therapy. METHODS: The study encompassed cirrhotic patients who underwent endoscopic therapy to prevent variceal rebleeding between January 2016 and October 2022. The L3-level CT images were obtained. Besides, impacts of subcutaneous adipose tissue index (SATI), visceral adipose tissue index (VATI), as well as total adipose tissue index (TATI) on rebleeding and mortality among cirrhotic patients following endoscopic therapy were examined. RESULTS: In this work, our median follow-up period was 31 months. Among those adipose tissue indexes, only SATI exhibited an independent relation to higher rebleeding (HR 0.981, 95% CI, 0.971-0.991, p < 0.001) and mortality (HR 0.965, 95% CI, 0.944-0.986, p = 0.001) risks. Upon multivariate Cox regression, low SATI (male < 30.15 cm2/m2, female < 39.82 cm2/m2) was independently linked to higher rebleeding risk (HR 2.511, 95% CI, 1.604-3.932, p < 0.001) and increased mortality risk (HR 3.422, 95% CI, 1.489-7.864, p = 0.004) after adjusting for other predictors. Furthermore, subgroups were created based on using nonselective ß-blockers (NSBBs), demonstrating that quantitatively assessing SATI exerts a vital role in evaluating rebleeding incidence in patients with or without NSBB therapy. CONCLUSION: This study underscores the potential of quantifying SATI as a means for achieving a more accurate risk classification for individual patients and identifying patients that can gain more benefits from nutritional intervention.


Assuntos
Varizes Esofágicas e Gástricas , Humanos , Feminino , Masculino , Varizes Esofágicas e Gástricas/cirurgia , Estudos Retrospectivos , Hemorragia Gastrointestinal , Prognóstico , Gordura Subcutânea/diagnóstico por imagem , Cirrose Hepática/complicações , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/cirurgia
3.
Angew Chem Int Ed Engl ; 63(6): e202318444, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38116912

RESUMO

Zn-MnO2 batteries have attracted extensive attention for grid-scale energy storage applications, however, the energy storage chemistry of MnO2 in mild acidic aqueous electrolytes remains elusive and controversial. Using α-MnO2 as a case study, we developed a methodology by coupling conventional coin batteries with customized beaker batteries to pinpoint the operating mechanism of Zn-MnO2 batteries. This approach visually simulates the operating state of batteries in different scenarios and allows for a comprehensive study of the operating mechanism of aqueous Zn-MnO2 batteries under mild acidic conditions. It is validated that the electrochemical performance can be modulated by controlling the addition of Mn2+ to the electrolyte. The method is utilized to systematically eliminate the possibility of Zn2+ and/or H+ intercalation/de-intercalation reactions, thereby confirming the dominance of the MnO2 /Mn2+ dissolution-deposition mechanism. By combining a series of phase and spectroscopic characterizations, the compositional, morphological and structural evolution of electrodes and electrolytes during battery cycling is probed, elucidating the intrinsic battery chemistry of MnO2 in mild acid electrolytes. Such a methodology developed can be extended to other energy storage systems, providing a universal approach to accurately identify the reaction mechanism of aqueous aluminum-ion batteries as well.

4.
J Insect Sci ; 23(4)2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37578847

RESUMO

The two-spotted spider mite, Tetranychus urticae Koch, has a broad host plant range and presents an extreme capacity for developing pesticide resistance, becoming a major economic pest in agriculture. Anticholinesterase insecticides still account for a big part of global insecticide sales. However, there is a growing concern about the serious resistance problems of anticholinesterase insecticides and their nontarget toxicity. In this study, structure-based virtual screening was performed to discover selective AChE inhibitors from the ChemBridge database, and 39 potential species-specific AChE inhibitor were obtained targeting T. urticae AChE, but not human AChE. Among them, compound No. 8 inhibited AChE from T. urticae, but not from human, and had an inhibitory activity comparable to that of eserine. Compound No. 8 had dose-dependent toxicity to T. urticae in glass slide-dipping assay and had significant mite control effects in a pot experiment, but required a high concentration to achieve similar control effects to spirodiclofen. The toxicity evaluation suggested that compound No. 8 had no acute toxicity on pollinator honey bees and natural predator N. californicus and did not affect strawberry growth in our assay. Compound No. 8 is a potential lead compound for developing novel acaricides with reduced nontarget toxicity.


Assuntos
Acaricidas , Inseticidas , Tetranychidae , Animais , Inseticidas/farmacologia , Inibidores da Colinesterase/farmacologia , Acetilcolinesterase , Acaricidas/farmacologia
5.
Small ; 18(34): e2203236, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35858243

RESUMO

Aluminum is the most abundant metal element in the Earth's crust, thus developing the rechargeable aluminum-ion batteries (AIBs) provides an ideal opportunity to realize cells with pleasing energy-to-price ratios. However, the further development of AIBs is plagued by the scarcity of suitable positive electrode materials. Here, for the first time, a tin-based alloy positive electrode material for AIBs, Co3 Sn2 wrapped with graphene oxide (Co3 Sn2 @GO composite) is well-designed and investigated to understand the aluminum storage behavior. A series of experimental measurements and theoretical calculations results reveal that a novel "bimetallic activated center alloying reaction" aluminum storage mechanism is occurred on the prepared Co3 Sn2 positive electrode. The reversible alloying/de-alloying process in AlCl3 /[EMIm]Cl ionic liquid, where both Co and Sn in Co3 Sn2 alloys react electrochemically with Al3+ to form Alx Sn and Aly Co is first put forward. This study delineates new insights on the aluminum storage mechanism, which may guide to ultimately exploit the energy benefits of "bimetallic activated center alloying redox".

6.
Appl Opt ; 59(14): 4542-4547, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400433

RESUMO

We demonstrate the dependencies of energy losses and fluorescent efficiencies on doping concentrations for rhodamine B (RhB)-doped polymer microfibers (PMFs) under optical waveguiding excitation. Compared with the four doping concentration groups (2.0 mg/g, 2.4 mg/g, 2.8 mg/g, and 3.2 mg/g), the 2.4 mg/g concentration group has the largest energy loss rates (∼0.102dB/µm and ∼0.036dB/µm for the excitation light and the fluorescence, respectively) and the highest fluorescence ratio at the coupling point. Further analysis demonstrates that the fluorescent emitting efficiency at the output end is approximately exponentially decaying with the propagation distance. The fluorescent emitting efficiency is also related to the doping concentration, which obtains the optimal fluorescent propagation effect at the doped PMF with a concentration of 2.8 mg/g. This work may provide a helpful reference for waveguiding circuit integration and active device design based on dye-doped micro/nanofibers.

7.
Front Oncol ; 14: 1404799, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39007100

RESUMO

Background: Our study aimed to develop a nomogram incorporating cytokeratin fragment antigen 21-1 (CYFRA21-1) to assist in differentiating between patients with intrahepatic cholangiocarcinoma (ICC) and hepatocellular carcinoma (HCC). Methods: A total of 487 patients who were diagnosed with ICC and HCC at Qilu Hospital of Shandong University were included in this study. The patients were divided into a training cohort and a validation cohort based on whether the data collection was retrospective or prospective. Univariate and multivariate analyses were employed to select variables for the nomogram. The discrimination and calibration of the nomogram were evaluated using the area under the receiver operating characteristic curve (AUC) and calibration plots. Decision curve analysis (DCA) was used to assess the nomogram's net benefits at various threshold probabilities. Results: Six variables, including CYFRA21-1, were incorporated to establish the nomogram. Its satisfactory discriminative ability was indicated by the AUC (0.972 for the training cohort, 0.994 for the validation cohort), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) values. The Hosmer-Lemeshow test and the calibration plots demonstrated favorable consistency between the nomogram predictions and the actual observations. Moreover, DCA revealed the clinical utility and superior discriminative ability of the nomogram compared to the model without CYFRA21-1 and the model consisting of the logarithm of alpha-fetoprotein (Log AFP) and the logarithm of carbohydrate antigen 19-9 (Log CA19-9). Additionally, the AUC values suggested that the discriminative ability of Log CYFRA21-1 was greater than that of the other variables used as diagnostic biomarkers. Conclusions: This study developed and validated a nomogram including CYFRA21-1, which can aid clinicians in the differential diagnosis of ICC and HCC patients.

8.
Ann Med ; 56(1): 2349180, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38699840

RESUMO

BACKGROUND: Sarcopenia is a common complication of liver cirrhosis and can be used for predicting dismal prognostic outcomes. This study aimed to evaluate the role of sarcopenia in rebleeding and mortality of liver cirrhosis patients after endoscopic therapy. METHODS: The liver cirrhosis patients who received endoscopic treatment were enrolled. Propensity score matching (PSM) was used to overcome selection bias. Two-year rebleeding episodes and mortality after endoscopic therapy were recorded. RESULTS: A total of 109 (32.4%) sarcopenia patients were reported. Before PSM, the frequency of rebleeding was significantly higher in the sarcopenia group relative to the non-sarcopenia group (41.3% vs. 15.9%, p < 0.001). Moreover, the multivariable analysis revealed that sarcopenia (p < 0.001, HR:2.596, 95% CI 1.591-4.237) was independently associated with a 2-year rebleeding episode. After PSM, the sarcopenia group exhibited an increased rebleeding rate as compared with non-sarcopenia group (44.4% vs. 15.3%, p < 0.001). According to multivariable analysis, sarcopenia (p < 0.001, HR:3.490, 95% CI 1.756-6.938) was identified as a significant predictor for 2-year rebleeding. CONCLUSION: Sarcopenia was significantly associated with a high 2-year rebleeding rate in liver cirrhosis patients after endoscopic treatment. Therefore, the precise evaluation of a patient's nutritional status, including sarcopenia becomes mandatory before endoscopic treatment.


Assuntos
Varizes Esofágicas e Gástricas , Hemorragia Gastrointestinal , Cirrose Hepática , Pontuação de Propensão , Recidiva , Sarcopenia , Humanos , Sarcopenia/etiologia , Sarcopenia/epidemiologia , Sarcopenia/complicações , Masculino , Feminino , Hemorragia Gastrointestinal/etiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Varizes Esofágicas e Gástricas/etiologia , Cirrose Hepática/complicações , Idoso , Adulto , Fatores de Risco , Prognóstico
9.
J Cardiothorac Surg ; 19(1): 59, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38317185

RESUMO

BACKGROUNDS: The internal fixation for rib fracture with single-operation-port (two ports) complete video-assisted thoracoscopic surgery (VATS) is a promising surgical approach for treating multiple rib fractures. The study aimed to investigate the minimally invasive surgical procedure's clinical effect in treating multiple rib fractures. METHODS: Seventy-three patients with multiple rib fractures were divided into two groups according to surgical procedure. In the study group, 42 patients were operated on with the internal fixation of rib fracture with single-operation-port complete VATS. In the control group, this study performed the open operative internal fixation for rib fracture with traditional thoracotomy on 31 patients. The surgical-related indexes were retrospectively analyzed. These included the operative time, the intraoperative blood loss, the drainage amount of the chest tube, the placement time of the chest tube, the postoperative hospital stay, the incidence of postoperative complications, the imaging efficacy of rib fixation of rib fractures, and visual analog scale of pain scoring (VAS scoring). RESULTS: There was no difference in the operative time between the study and control groups (P = 0.806). The intraoperative blood loss, the chest tube drainage amount, the chest tube placement time, the postoperative hospital stay, and the incidence of postoperative complications in the study group were lower than those in the control group (P < 0.05). There was no significant difference in the imaging efficacy of rib fixation of rib fractures between the two groups (P = 0.806). VAS scores in the study group on the seventh postoperative day were significantly reduced compared with the control group (P = 0.026). CONCLUSION: The internal fixation for rib fractures with single-operation-port complete VATS is a feasible, safe, simple, and minimally invasive surgical procedure to treat multiple rib fractures, which is worthy of clinical application.


Assuntos
Fraturas das Costelas , Cirurgia Torácica Vídeoassistida , Humanos , Cirurgia Torácica Vídeoassistida/métodos , Fraturas das Costelas/cirurgia , Estudos Retrospectivos , Perda Sanguínea Cirúrgica , Fixação Interna de Fraturas/métodos , Complicações Pós-Operatórias
10.
Adv Biol (Weinh) ; 8(9): e2400064, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38837746

RESUMO

A compelling correlation method linking microbial communities and host gene expression in tissues is currently absent. A novel pipeline is proposed, dubbed Transcriptome Analysis of Host-Microbiome Crosstalk (TAHMC), designed to concurrently restore both host gene expression and microbial quantification from bulk RNA-seq data. Employing this approach, it discerned associations between the tissue microbiome and host immunity in the context of Crohn's disease (CD). Further, machine learning is utilized to separately construct networks of associations among host mRNA, long non-coding RNA, and tissue microbes. Unique host genes and tissue microbes are extracted from these networks for potential utility in CD diagnosis. Experimental validation of the predicted host gene regulation by microbes from the association network is achieved through the co-culturing of Faecalibacterium prausnitzii with Caco-2 cells. Collectively, the TAHMC pipeline accurately recovers both host gene expression and microbial quantification from CD RNA-seq data, thereby illuminating potential causal links between shifts in microbial composition as well as diversity within CD mucosal tissues and aberrant host gene expression.


Assuntos
Doença de Crohn , Microbioma Gastrointestinal , Doença de Crohn/microbiologia , Doença de Crohn/genética , Humanos , Microbioma Gastrointestinal/genética , Células CACO-2 , Perfilação da Expressão Gênica/métodos , Faecalibacterium prausnitzii/genética , Aprendizado de Máquina , Transcriptoma
11.
Chem Commun (Camb) ; 58(78): 10981-10984, 2022 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-36093729

RESUMO

A nanocomposite consisting of iron telluride wrapped with graphene oxide (GO) was prepared via a hydrothermal method. As the cathode material for aluminum-ion batteries (AIBs), it exhibited a remarkable long-term cycle performance with a reversible capacity of 120.4 mA h g-1 at 1 A g-1 after 10 000 cycles, i.e., a cyclability better than those of all other transition metal chalcogenides in AIBs reported to date. Furthermore, an energy storage mechanism, involving the intercalation and deintercalation of multiple ions (AlCl4-, Cl- and Al3+), was elucidated. This study offers guidance for further development of transition metal tellurides for AIBs.

12.
Chem Sci ; 13(47): 14191-14197, 2022 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-36540814

RESUMO

Rechargeable aluminum-ion batteries have attracted increasing attention owing to the advantageous multivalent ion storage mechanism thus high theoretical capacity as well as inherent safety and low cost of using aluminum. However, their development has been largely impeded by the lack of suitable positive electrodes to provide both sufficient energy density and satisfactory rate capability. Here we report a candidate positive electrode based on ternary metal oxides, Fe2(MoO4)3, which was assembled by cross-stacking of porous nanosheets, featuring superior rate performance and cycle stability, and most importantly a well-defined discharge voltage plateau near 1.9 V. Specifically, the positive electrode is able to deliver reversible capacities of 239.3 mA h g-1 at 0.2 A g-1 and 73.4 mA h g-1 at 8.0 A g-1, and retains 126.5 mA h g-1 at 1.0 A g-1 impressively, after 2000 cycles. Furthermore, the aluminum-storage mechanism operating on Al3+ intercalation in this positive electrode is demonstrated for the first time via combined in situ and ex situ characterization studies and density functional theory calculations. This work not only explores potential positive electrodes for aluminum-based batteries but also sheds light on the fundamental charge storage mechanism within the electrode.

13.
Materials (Basel) ; 14(20)2021 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-34683754

RESUMO

From the perspective of improving the self-healing method in construction, a tubular healing fiber was adopted as a container to improve the encapsulation capacity, which was available using a micro-capsule as a container. Knowing the direction of the stresses to which structure members are subjected, this research investigated the influence of aligning tubular healing fibers parallel to intended stress into a cementitious composite to increase the self-healing capability. For that, a healing agent was encapsulated into a tubular healing fiber made with polyvinylidene of fluoride resin (PVDF). Then, the healing fiber was combined with steel fibers to align both fibers together parallel to the direction of an intended splitting tensile stress when subjected to a magnetic field in a cylindrical cementitious composite. The alignment method and the key point through which the alignment of the healing fibers could efficiently improve autonomic self-healing were investigated. Since the magnetic field is known to be able to drag steel to an expected direction, steel fibers were combined with the healing fibers to form a hybrid fiber that aligned both fibers together. The required mixture workability was investigated to avoid the sinking of the healing fibers into the mixture. The healing efficiency, according to the orientation of the healing fibers in the composite matrix, was evaluated through a permeability test and a repetitive splitting tensile test. The aligned healing fibers performed better than the randomly distributed healing fibers. However, according to the healing efficiency with aligned healing fibers, it was deduced that the observed decreasing effect of the container's alignment on the specimen's mechanical properties was low enough to be neglected.

14.
Front Chem ; 9: 834418, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35186900

RESUMO

The pursuit of electrochemical energy storage has led to a pressing need on materials with high capacities and energy densities; however, further progress is plagued by the restrictive capacity (372 mAh g-1) of conventional graphite materials. Tungsten trioxide (WO3)-based anodes feature high theoretical capacity (693 mAh g-1), suitable potential, and affordable cost, arousing ever-increasing attention and intense efforts. Nonetheless, developing high-performance WO3 electrodes that accommodate lithium ions remains a daunting challenge on account of sluggish kinetics characteristics and large volume strain. Herein, the well-designed hierarchical WO3 agglomerates assembled with straight and parallel aligned nanoribbons are fabricated and evaluated as an anode of lithium-ion batteries (LIBs), which exhibits an ultra-high capacity and excellent rate capability. At a current density of 1,000 mA g-1, a reversible capacity as high as 522.7 mAh g-1 can be maintained after 800 cycles, corresponding to a high capacity retention of ∼80%, demonstrating an exceptional long-durability cyclic performance. Furthermore, the mechanistic studies on the lithium storage processes of WO3 are probed, providing a foundation for further optimizations and rational designs. These results indicate that the well-designed hierarchical WO3 agglomerates display great potential for applications in the field of high-performance LIBs.

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