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1.
Nano Lett ; 24(8): 2503-2510, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38258747

RESUMO

X-ray scintillators have utility in radiation detection, therapy, and imaging. Various materials, such as halide perovskites, organic illuminators, and metal clusters, have been developed to replace conventional scintillators due to their ease of fabrication, improved performance, and adaptability. However, they suffer from self-absorption, chemical instability, and weak X-ray stopping power. Addressing these limitations, we employ alkali metal doping to turn nonemissive CsPb2Br5 into scintillators. Introducing alkali metal dopants causes lattice distortion and enhances electron-phonon coupling, which creates transient potential energy wells capable of trapping photogenerated or X-ray-generated electrons and holes to form self-trapped excitons. These self-trapped excitons undergo radiative recombination, resulting in a photoluminescence quantum yield of 55.92%. The CsPb2Br5-based X-ray scintillator offers strong X-ray stopping power, high resistance to self-absorption, and enhanced stability when exposed to the atmosphere, chemical solvents, and intense irradiation. It exhibits a detection limit of 162.3 nGyair s-1 and an imaging resolution of 21 lp mm-1.

2.
Anal Chem ; 96(8): 3553-3560, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38362858

RESUMO

Lead halide perovskite nanocrystals with excellent photophysical properties are promising electrochemiluminescence (ECL) candidates, but their poor stability greatly restricts ECL applications. Herein, hydrogen-bonded cocrystal-encapsulated CsPbBr3 perovskite nanocrystals (PeNCs@NHS-M) were synthesized by using PeNCs as nuclei for inducing the crystallization of melamine (M) and N-hydroxysuccinimide (NHS). The as-synthesized composite exhibits multiplicative ECL efficiencies (up to 24-fold that of PeNCs) without exogenous coreactants and with excellent stability in the aqueous phase. The enhanced stability can be attributed to the well-designed heterostructure of the PeNCs@NHS-M composite, which benefits from both moiety passivation and protection of the peripheral cocrystal matrix. Moreover, the heterostructure with covalent linkage facilitates charge transfer between PeNCs and NHS-M cocrystals, realizing effective ECL emission. Meanwhile, the NHS and M components act as coreactants for PeNCs, shortening the electron-transport distance and resulting in a significant increase in the ECL signal. Furthermore, by taking advantage of the specific binding effect between NHS-M and uranyl (UO22+), an ECL system with both a low detection limit (1 nM) and high selectivity for monitoring UO22+ in mining wastewater is established. The presence of UO22+ disrupted the charge-transfer effect within PeNCs@NHS-M, weakening the ECL signals. This work provides an efficient design strategy for obtaining stable and efficient ECLs from perovskite nanocrystals, offering a new perspective for the discovery and application of perovskite-based ECL systems.

3.
Anal Chem ; 96(12): 5037-5045, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38477697

RESUMO

Uranium poses severe health risks due to its radioactivity and chemical toxicity if released into the environment. Therefore, there is an urgent demand to develop sensing materials in situ monitoring of uranium with high sensitivity and stability. In this work, a fluorescent Eu3+-TFPB-Bpy is synthesized by grafting Eu3+ cation onto TFPB-Bpy covalent organic framework (COF) synthesized through Schiff base condensation of monomers 1,3,5-tris(4-formylphenyl)benzene (TFPB) and 5,5'-diamino-2,2'-bipyridine (Bpy). The fluorescence of Eu3+-TFPB-Bpy is enhanced compared with that of TFPB-Bpy, which is originated from the intramolecular rotations of building blocks limited by the bipyridine units of TFPB-Bpy coordinated with Eu3+. More significantly, Eu3+-TFPB-Bpy is a highly efficient probe for sensing UO22+ in aqueous solution with the luminescence intensity efficiently amplified by complexation of UO22+ with Eu3+. The turn-on sensing capability was derived from the resonance energy transfer occurring from UO22+ to the Eu3+-TFPB-Bpy. The developed probe displayed desirable linear range from 5 nM to 5 µM with good selectivity and rapid response time (2 s) for UO22+ in mining wastewater. This strategy provides a vivid illustration for designing luminescence lanthanide COF hybrid materials with applications in environmental monitoring.

4.
Anal Chem ; 96(11): 4623-4631, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38456770

RESUMO

Developing new electrochemiluminescence (ECL) luminators with high stability, wide applicability, and strong designability is of great strategic significance to promote the ECL field to the frontier. Here, driven by the I···N bond, 1,3,5-trifluoro-2,4,6-triiodobenzene (TFTI) and 2,4,6-trimethyl-1,3,5-triazine (TMT) self-assembled into a novel halogen cocrystal (TFTI-TMT) through slow solution volatilization. Significant difference of charge density existed between the N atoms on TMT and the σ-hole of the I atoms on TFTI. Upon the induction of σ-hole effect, high-speed and spontaneous charge transferring from TMT to the σ-hole of TFTI occurred, stimulating exciting ECL signals. Besides, the σ-hole of the I atoms could capture iodine ions specifically, which blocked the original charge transfer from the N atoms to the σ-hole, causing the ECL signal of TFTI-TMT to undergo a quenching rate as high as 92.9%. Excitingly, the ECL sensing of TFTI-TMT toward I- possessed a wide linear range (10-5000 nM) and ultralow detection limit (3 nM) in a real water sample. The halogen cocrystal strategy makes σ-hole a remarkable new viewpoint of ECL luminator design and enables ECL analysis technology to contribute to addressing the environmental and health threats posed by iodide pollution.

5.
Small ; 20(25): e2310672, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38229539

RESUMO

At present, poor stability and carrier transfer efficiency are the main problems that limit the development of perovskite-based photoelectric technologies. In this work, hydrogen-bonded cocrystal-coated perovskite composite (PeNCs@NHS-M) is easily obtained by inducing rapid crystallization of melamine (M) and N-hydroxysuccinimide (NHS) with PeNCs as the nuclei. The outer NHS-M cocrystal passivates the undercoordinated lead atoms by forming covalent bonds, thereby greatly reducing the trap density while maintaining good structure stability for perovskite nanocrystals. Moreover, benefiting from the interfacial covalent band linkage and long-range ordered structures of cocrystals, the charge transfer efficiency is effectively enhanced and PeNCs@NHS-M displays superior photoelectric performance. Based on the excellent photoelectric performance and abundant active sites of PeNCs@NHS-M, photocatalytic reduction of uranium is realized. PeNCs@NHS-M exhibits U(VI) reduction removal capability of up to 810.1 mg g-1 in the presence of light. The strategy of cocrystals trapping perovskite nanocrystals provides a simple synthesis method for composites and opens up a new idea for simultaneously improving the stability and photovoltaic performance of perovskite.

6.
Inorg Chem ; 63(24): 11459-11469, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38842950

RESUMO

The performance of covalent-organic frameworks (COFs) for the photocatalytic extraction of uranium is greatly limited by the number of adsorption sites. Herein, inspired by electronegative redox reactions, we designed a nitrogen-oxygen rich pyrazine connected COF (TQY-COF) with multiple redox sites as a platform for extracting uranium via combining superaffinity and enhanced photoinduction. The preorganized bisnitrogen-bisoxygen donor configuration on TQY-COF is entirely matched with the typical geometric coordination of hexavalent uranyl ions, which demonstrates high affinity (tetra-coordination). In addition, the presence of the carbonyl group and pyrazine ring effectively stores and controls electron flow, which efficaciously facilitates the separation of e-/h+ and enhances photocatalytic performance. The experimental results show that TQY-COF removes up to 99.8% of uranyl ions from actual uranium mine wastewater under the light conditions without a sacrificial agent, and the separation coefficient reaches 1.73 × 106 mL g-1 in the presence of multiple metal ions, which realizes the precise separation in the complex environment. Importantly, DFT calculations further elucidate the coordination mechanism of uranium and demonstrate the necessity of the presence of N/O atoms in the photocatalytic adsorption of uranium.

7.
Surg Endosc ; 38(6): 3126-3137, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38622226

RESUMO

BACKGROUND: The use of high-frequency electric welding technology for intestinal end-to-end anastomosis holds significant promise. Past studies have focused on in vitro, and the safety and efficacy of this technology is uncertain, severely limiting the clinical application of this technology. This study investigates the impact of compression pressure, energy dosage, and duration on anastomotic quality using a homemade anastomosis device in both in vitro and in vivo settings. METHODS: Two hundred eighty intestines and 5 experimental pigs were used for in vitro and in vivo experiments, respectively. The in vitro experiments were conducted to study the effects of initial pressure (50-400 kpa), voltage (40-60 V), and time (10-20 s) on burst pressure, breaking strength, thermal damage, and histopathological microstructure of the anastomosis. Optimal parameters were then inlaid into a homemade anastomosis and used for in vivo experiments to study the postoperative porcine survival rate and the pathological structure of the tissues at the anastomosis and the characteristics of the collagen fibers. RESULTS: The anastomotic strength was highest when the compression pressure was 250 kPa, the voltage was 60 V, and the time was 15 s. The degree of thermal damage to the surrounding tissues was the lowest. The experimental pigs had no adverse reactions after the operation, and the survival rate was 100%. 30 days after the operation, the surgical site healed well, and the tissues at the anastomosis changed from immediate adhesions to permanent connections. CONCLUSION: High-frequency electric welding technology has a certain degree of safety and effectiveness. It has the potential to replace the stapler anastomosis in future and become the next generation of new anastomosis device.


Assuntos
Anastomose Cirúrgica , Intestino Delgado , Pressão , Animais , Anastomose Cirúrgica/métodos , Suínos , Intestino Delgado/cirurgia , Resistência à Tração , Técnicas In Vitro
8.
Appl Opt ; 63(12): 3228-3236, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856471

RESUMO

Due to its numerous advantages such as high gain and low operating bias, the silicon photomultiplier (SiPM) holds great potential in LiDAR applications. However, it is more jittery at weak echoes and more sensitive to ambient light, making its ranging performance at low signal-to-noise ratios (SNRs) severely deteriorated. To enhance the ranging performance of SiPM LiDAR under low SNR, a novel echo processing method, to the best of our knowledge, was proposed based on the statistical property of SiPM responses and validated under relatively intensive sunlight (>50k l x) using a self-developed LiDAR system. At the same time, laser pulse width modulation and multi-pulse laser emission are used in ranging experiments to maximize the advantages of this method. It has shown that increasing the laser pulse width within a certain range can improve ranging performance, and that emitting multiple laser pulses improves ranging performance more significantly. Utilizing a three-pulse laser with a peak power of only 3.2 W, a target 122 m away was ranged with a precision of 6.53 cm with only five accumulations.

9.
Neoplasma ; 71(1): 1-12, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38295103

RESUMO

Semaphorins are originally described as regulators of nervous system development. Besides, members of the semaphorin family play important roles in the growth, metastasis, and angiogenesis of solid tumors. In contrast to the other semaphorin subclasses, semaphorin class 4 has both membrane-bound and active soluble forms. Soluble class 4 semaphorins in body fluids (blood and saliva) may serve as potential biomarkers for early diagnosis and prognosis prediction of specific cancers. The class 4 semaphorins also transduce signal in cancer cells in a cell membrane-bound form, thereby regulating cancer progression. In solid tumors, class 4 semaphorins can act as ligands in active soluble forms, regulating cancer progression via autocrine and paracrine to activate signal transduction in cancer cells or endothelial cells in the tumor microenvironment. Targeting class 4 semaphorins may be a novel strategy for specific cancer therapy. However, the expression of class 4 semaphorins in solid tumors and the responsive pathogenesis are still controversial. Therefore, this review summarizes the specific expression regulation of class 4 semaphorin members in different types of solid tumors and the mechanisms involved in cancer progression.


Assuntos
Neoplasias , Semaforinas , Humanos , Neovascularização Patológica/patologia , Semaforinas/genética , Células Endoteliais , Neoplasias/metabolismo , Transdução de Sinais/fisiologia , Microambiente Tumoral
10.
Artigo em Inglês | MEDLINE | ID: mdl-38758153

RESUMO

Context: Gastric cancer (GC) is a common and life-threatening gastrointestinal malignancy. Although mucin 3A (MUC3A) is an essential oncogenic factor in several cancers, limited information is available on its expression in GC tissues and its impact on prognosis. Objective: The study aimed to characterize MUC3A in GC and to explore its potential involvement in regulating GC cells' behavior through the mammalian target of rapamycin (mTOR) signaling pathway. Design: The research team conducted a retrospective genetic analysis. Setting: The study took place as Huzhou Central Hospital, an Affiliated Central Hospital of Huzhou University in Huzhou, Zhejiang, China. Participants: Participants were 47 patients with GC who had received treatment at the department of general surgery at the hospital and who gave consent for the use of their tissue samples for the genetic analysis. Outcome Measures: The research team: (1) performed a differential analysis of MUC3A using GC and normal tissue samples purchased from the American Type Culture Collection; (2) investigated the exposure of cancer tissues to MUC3A and its effects in the tumor, node, metastasis (TNM) stages of GC, using the real-time quantitative polymerase chain reaction (rt-qPCR) method; (3) performed clone formation and conducted transwell assays by knocking down or overexpressing MUC3A to analyze the effects on the behavior of GC cells; and (4) assessed the content of related marker proteins and the phosphoinositide 3-kinase (PI3K)/ protein kinase B (Akt)/ mammalian target of rapamycin (mTOR) pathway proteins, using a Western blot analysis. Results: A high level of MUC3A existed in GC tissues, and it was associated with TNM staging. Silencing of the MUC3A inhibited GC-cell migration and proliferation, and MUC3A overexpression had the opposite effect. The addition of agonist M05856 restored the inhibitory effect of silencing MUC3A on GC cell proliferation and migration, suggesting that MUC3A regulates GC cells' behavior through the PI3K/Akt/mTOR pathway. Conclusions: MUC3A plays an oncogenic role in GC and may regulate GC cell behavior through the PI3K/Akt/mTOR pathway.

11.
Ecotoxicol Environ Saf ; 279: 116500, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38795416

RESUMO

Hexavalent chromium [Cr(VI)] is one of the most common environmental contaminants due to its tremendous industrial applications, but its effects and mechanism remain to be investigated. Our previous studies showed that Cr(VI) exposure caused malignant transformation and tumorigenesis. This study showed that glycolytic proteins HK2 and LDHA levels were statistically significant changed in blood samples of Cr(VI)-exposed workers and in Cr-T cells compared to the control subjects and parental cells. HK2 and LDHA knockdown inhibited cell proliferation and angiogenesis, and higher HK2 and LDHA expression levels are associated with advanced stages and poor prognosis of lung cancer. We found that miR-218 levels were significantly decreased and miR-218 directly targeted HK2 and LDHA for inhibiting their expression. Overexpression of miR-218 inhibited glucose consumption and lactate production in Cr-T cells. Further study found that miR-218 inhibited tumor growth and angiogenesis by decreasing HK2 and LDHA expression in vivo. MiR-218 levels were negatively correlated with HK2 and LDHA expression levels and cancer development in human lung and other cancers. These results demonstrated that miR-218/HK2/LDHA pathway is vital for regulating Cr(VI)-induced carcinogenesis and human cancer development.


Assuntos
Carcinogênese , Cromo , Hexoquinase , Neoplasias Pulmonares , MicroRNAs , Regulação para Cima , MicroRNAs/genética , Humanos , Cromo/toxicidade , Hexoquinase/genética , Hexoquinase/metabolismo , Carcinogênese/induzido quimicamente , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/genética , Prognóstico , Animais , Proliferação de Células/efeitos dos fármacos , L-Lactato Desidrogenase/metabolismo , Exposição Ocupacional/efeitos adversos , Camundongos , Isoenzimas
12.
BMC Surg ; 24(1): 50, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336762

RESUMO

BACKGROUND: There is no criterion to guide and evaluate the anastomosis of laparoscopic low anterior resection (LAR). We developed a new technique for precise anastomosis. This study endeavored to evaluate the effectiveness and safety of this new technology. METHODS: Patients with mid-low rectal cancer who underwent laparoscopic LAR in our department were enrolled retrospectively between January 1, 2021 and July 1, 2023. During the LAR, the distance between the sacral promontory and the rectal stump was measured and used to determine the length of the sigmoid colon, which was preserved for anastomose. The demographic characteristics and short-term outcomes were analyzed. RESULTS: Forty-nine patients (26 men, 23 women) with low and middle rectal cancer were retrospectively enrolled in the study. The distance of the tumor from the anal verge was 6.4 ± 2.7 cm. The operative time was 193 ± 42 min. All patients underwent precise anastomosis, among which 12 patients underwent freeing of the splenic flexure of the colon. According to our criteria, there was no redundant or tense state of the colon anterior to the sacrum after the anastomosis. Only one patient had a postoperative anastomotic leak (Grade B). All 15 patients receiving neoadjuvant chemoradiotherapy underwent terminal ileostomy. No postoperative death occurred within 30 days of the surgery. The median follow-up time in our study was 12 months. One patient developed a single metastasis in the right lobe of the liver in the eighth month after surgery and underwent microwave radiofrequency ablation, which did not recur in the four months of postoperative follow-up, and the rest of the patients survived disease-free without recurrence of metastasis. CONCLUSIONS: Precise measurement of the proximal colon of the anastomosis can ensure accurate and convenient colorectal anastomosis and this may be a technique worthy of clinical application. However, its effectiveness needs to be further verified in a multicenter clinical trial.


Assuntos
Laparoscopia , Neoplasias Retais , Masculino , Humanos , Feminino , Estudos Retrospectivos , Neoplasias Retais/patologia , Anastomose Cirúrgica/métodos , Reto/cirurgia , Reto/patologia , Laparoscopia/métodos , Fístula Anastomótica/etiologia
13.
Angew Chem Int Ed Engl ; 63(18): e202401949, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38437064

RESUMO

X-ray scintillators have gained significant attention in medical diagnostics and industrial applications. Despite their widespread utility, scintillator development faces a significant hurdle when exposed to elevated temperatures, as it usually results in reduced scintillation efficiency and diminished luminescence output. Here we report a molecular design strategy based on a hybrid perovskite (TpyBiCl5) that overcomes thermal quenching through multi-excited state switching. The structure of perovskite provides a platform to modulate the luminescence centers. The rigid framework constructed by this perovskite structure stabilized its triplet states, resulting in TpyBiCl5 exhibiting an approximately 12 times higher (45 % vs. 3.8 %) photoluminescence quantum yield of room temperature phosphorescence than that of its organic ligand (Tpy). Most importantly, the interactions between the components of this perovskite enable the mixing of different excited states, which has been revealed by experimental and theoretical investigations. The TpyBiCl5 scintillator exhibits a detection limit of 38.92 nGy s-1 at 213 K and a detection limit of 196.31 nGy s-1 at 353 K through scintillation mode switching between thermally activated delayed fluorescence and phosphorescence. This work opens up the possibility of solving the thermal quenching in X-ray scintillators by tuning different excited states.

14.
Angew Chem Int Ed Engl ; : e202413071, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39103902

RESUMO

A rapid in situ synthesis of electrochromic covalent organic frameworks (EC-COFs) was proposed by using green electrochemical interface polymerization of N,N,N',N'-tetrakis(p-aminophenyl)p-phenylenediamine (TPDA) and 2,5-dihydroxy-p-phenylenedicarboxaldehyde (DHBD). The synthetized TPDA-DHBD films exhibit stable polymorphic colour variations under different applied potentials, which can be attributed to the redox state changes of bis(triphenylamine) and imine electroactive functional groups within the COFs skeleton. TPDA-DHBD represents markedly different electrochromisms from red to cyan due to the steric hindrance effect caused by the presence of UO22+, demonstrating the unique tunability of COFs materials. This work offers a new feasible idea for rapid EC-COFs synthesis and tunable EC-COFs realization.

15.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(6): 611-618, 2024 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-38926378

RESUMO

OBJECTIVES: To investigate the risk factors for bronchopulmonary dysplasia (BPD) in twin preterm infants with a gestational age of <34 weeks, and to provide a basis for early identification of BPD in twin preterm infants in clinical practice. METHODS: A retrospective analysis was performed for the twin preterm infants with a gestational age of <34 weeks who were admitted to 22 hospitals nationwide from January 2018 to December 2020. According to their conditions, they were divided into group A (both twins had BPD), group B (only one twin had BPD), and group C (neither twin had BPD). The risk factors for BPD in twin preterm infants were analyzed. Further analysis was conducted on group B to investigate the postnatal risk factors for BPD within twins. RESULTS: A total of 904 pairs of twins with a gestational age of <34 weeks were included in this study. The multivariate logistic regression analysis showed that compared with group C, birth weight discordance of >25% between the twins was an independent risk factor for BPD in one of the twins (OR=3.370, 95%CI: 1.500-7.568, P<0.05), and high gestational age at birth was a protective factor against BPD (P<0.05). The conditional logistic regression analysis of group B showed that small-for-gestational-age (SGA) birth was an independent risk factor for BPD in individual twins (OR=5.017, 95%CI: 1.040-24.190, P<0.05). CONCLUSIONS: The development of BPD in twin preterm infants is associated with gestational age, birth weight discordance between the twins, and SGA birth.


Assuntos
Displasia Broncopulmonar , Recém-Nascido Prematuro , Gêmeos , Humanos , Displasia Broncopulmonar/etiologia , Displasia Broncopulmonar/epidemiologia , Fatores de Risco , Recém-Nascido , Feminino , Estudos Retrospectivos , Masculino , Idade Gestacional , Peso ao Nascer , Modelos Logísticos
16.
Bioresour Technol ; 401: 130718, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38641303

RESUMO

Recently, microalgae had received extensive attention for carbon capture and utilization. But its overall efficiency still could not reach a satisfactory degree. Artificial photosynthesis showed better efficiency in the conversion of carbon dioxide. However, artificial photosynthesis could generally only produce C1-C3 organic matters at present. Some studies showed that heterotrophic microalgae can efficiently synthesize high value organic matters by using simple organic matter such as acetate. Therefore, the combination of artificial photosynthesis with heterotrophic microalgae culture showed great potential for efficient carbon capture and high-value organic matter production. This article systematically analyzed the characteristics and challenges of carbon dioxide conversion by microalgae and artificial photosynthesis. On this basis, the coupling mode and development trend of artificial photosynthesis combined with microalgae culture were discussed. In summary, the combination of artificial photosynthesis and microalgae culture has great potential in the field of carbon capture and utilization, and deserves further study.


Assuntos
Dióxido de Carbono , Microalgas , Fotossíntese , Microalgas/metabolismo , Dióxido de Carbono/metabolismo , Biotecnologia/métodos , Carbono/metabolismo
17.
PLoS One ; 19(2): e0292380, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38329990

RESUMO

This article proposes a continuous-time optimization approch instead of tranditional optimiztion methods to address the nuclear norm minimization (NNM) problem. Refomulating the NNM into a matrix form, we propose a Lagrangian programming neural network (LPNN) to solve the NNM. Moreover, the convergence condtions of LPNN are presented by the Lyapunov method. Convergence experiments are presented to demonstrate the convergence of LPNN. Compared with tranditional algorithms of NNM, the proposed algorithm outperforms in terms of image recovery.


Assuntos
Algoritmos , Redes Neurais de Computação
18.
ACS Appl Mater Interfaces ; 16(10): 12731-12743, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38421155

RESUMO

Efficient and rapid screening of target materials in a vast material space remains a significant challenge in the field of materials science. In this study, first-principles calculations and machine learning algorithms are performed to search for high out-of-plane piezoelectric stress coefficient materials in the MXene functional database among the 1757 groups of noncentrosymmetric MXenes with nonzero band gaps, which meet the criteria for piezoelectric properties. For the monatomic MXene testing set, the random forest regression (RFR), gradient boosting regression (GBR), support vector regression (SVR), and multilayer perceptron regression (MLPR) exhibit R2 values of 0.80, 0.80, 0.89, and 0.87, respectively. Expanding our analysis to the entire MXene data set, the best active learning cycle finds more than 140 and 22 MXenes with out-of-plane piezoelectric stress coefficients (e31) exceeding 3 × 10-10 and 5 × 10-10 C/m, respectively. Moreover, thermodynamic stabilities were confirmed in 22 MXenes with giant piezoelectric stress coefficients and 9 MXenes with both large in-plane (d11 > 15 pm/V) and out-of-plane (d31 > 2 pm/V) piezoelectric strain coefficients. These findings highlight the remarkable capabilities of machine learning and its optimization algorithms in accelerating the discovery of novel piezoelectric materials, and MXene materials emerge as highly promising candidates for piezoelectric materials.

19.
Aging (Albany NY) ; 16(3): 3007-3020, 2024 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-38345576

RESUMO

Related studies have shown that ITGB2 mediates mitochondrial glycolytic transformation in cancer-associated fibroblasts and participates in tumor occurrence, metastasis and invasion of cancer cells. Based on these studies, we tried to construct a mitochondrial glycolysis regulatory network and explored its effect on mitochondrial homeostasis and ovarian cancer cells' cancerous characteristics. Our research revealed a distinct increase in the expression of ITGB2 and associated signaling pathway elements (PI3K-AKT-mTOR) in cases of ovarian cancer. ITGB2 might control mTOR expression via the PI3K-AKT pathway, thus promote mitochondrial glycolysis transformation and cell energy supply in ovarian cancer. This pathway could also inhibit mitophagy, maintain mitochondrial stability, and enhance the cancerous characteristics in case of ovarian cancer cells by mediating mitochondrial glycolytic transformation. Thus, we concluded that ITGB2-associated signaling route (PI3K-AKT-mTOR) may contribute to the progression of cancerous traits in ovarian cancer via mediating mitochondrial glycolytic transformation.


Assuntos
Neoplasias Ovarianas , Proteínas Proto-Oncogênicas c-akt , Humanos , Feminino , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Linhagem Celular Tumoral , Neoplasias Ovarianas/patologia , Serina-Treonina Quinases TOR/metabolismo , Glicólise , Proliferação de Células
20.
Waste Manag ; 183: 191-198, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-38761483

RESUMO

With the development of municipal solid waste incineration technologies, the disposal of fly ash has become a difficult problem that many countries need to solve. High-temperature melting is a promising disposal technology. Based on this, a new process for collaborative treatment of fly ash in metallurgical blast furnaces had been proposed in this study. To explore the impact of disposal of fly ash on blast furnace production, by simulating the high-temperature reducing environment of blast furnaces, the melting changes of water-washed fly ash (W-FA), and the effects of W-FA injection on coal combustion and products (slag, iron) composition were studied. The results showed that W-FA, as a flux, could be sprayed into the blast furnace separately or mixed with coal. But when injected along with coal, W-FA would suppress the combustion of coal. After melting, the removal rates of S, P, Cl, and Pb in W-FA were 21%, 30%, 86%, and 89%, respectively. The removal rates of K, Na, and Zn were close to 100%, and Cr was basically not removed. When the proportion of W-FA to coal was less than 1%, in addition to controlling the alkalinity of the slag, the impact of W-FA on the composition of iron and slag was minimal. The successful execution of this work will not only achieve the reduction, harmless and resourceful utilization of fly ash, but also save investment and operating costs of disposal facilities, with both environmental and social benefits.


Assuntos
Cinza de Carvão , Incineração , Eliminação de Resíduos , Resíduos Sólidos , Cinza de Carvão/química , Incineração/métodos , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Temperatura Alta , Carvão Mineral
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