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1.
Int J Surg ; 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39264581

RESUMO

BACKGROUND: Oncoplastic breast-conserving surgery (OBCS) improves satisfaction in patients who would fare otherwise sub-optimal cosmetic outcome, while brings challenge in tumor-bed identification during adjuvant radiotherapy. The ultra-hypofractionated breast radiotherapy further shortens treatment sessions from moderately hypofractionated regimens. To circumscribe the difficulty in tumor-bed contouring and the additional toxicity from larger boost volumes, we propose to move forward the boost session preoperatively from the adjuvant radiation part. Thus, the present study aims to evaluate the feasibility of a new treatment paradigm of preoperative primary-tumor boost before breast-conserving surgery (BCS) or OBCS followed by adjuvant ultra-hypofractionated whole-breast irradiation (u-WBRT) for patients with early-stage breast cancer. METHODS: There was a phase II study. Patients younger than 55 years old, with a biopsy confirmed mono-centric breast cancer, without lymph node involvement were enrolled. Preoperative primary-tumor boost was given by a single 10 Gy in 1 fraction, and BCS or OBCS was conducted within two weeks afterwards. Adjuvant u-WBRT (26 Gy/5.2 Gy/5 f) was given in 6 weeks postoperatively without any boost, after the full recovery from surgery. Surgical complications and patient-reported outcomes, as assessed via Breast-Q questionnaires, were documented. A propensity score matching approach was employed to identify a control group at a 1:1 ratio for BREAST-Q outcomes comparison. RESULTS: From May 2022 to September 2023, 36 patients were prospectively enrolled. Surgical complications were observed in 7 cases (19.4%), including 3 cases with Clavien-Dindo (CD) grade 1-2 and 4 cases with CD grade 3 complications. All but four patients (11.1%) started the planned u-WBRT within one week after the pre-defined due dates postoperatively (≤49 d). Four patients (11.1%) developed grade 2 radiodermatitis after chemotherapy initiation. Compared to the study group, the control patients reported higher scores in chest physical well-being (P=0.045) and in their attitudes towards arm swelling (P=0.01). No significant difference was detected in the other of domains (Satisfaction with Breasts, Sexual and Psychosocial Well-Being, and Adverse Effects of Radiation). With a median follow-up period of 9.8 months (2.4-18.9 mo), none had any sign of relapse. CONCLUSION: This Phase II clinical trial confirmed the technical and safety feasibility of novel radiation schedule in patients undergoing BCS or OBCS. According to the BREAST-Q questionnaire, patients who underwent novel radiation schedules reported lower satisfaction in chest physical well-being. A randomized controlled trial is necessary to further investigate these findings. Additionally, long-term follow-up is required to assess oncological outcomes.

2.
Rev Sci Instrum ; 95(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39283188

RESUMO

In contemporary industrial systems, the prediction of remaining useful life (RUL) is recognized as a valuable maintenance strategy for health management due to its ability to monitor equipment operational status in real time and ensure the safety of industrial production. Current studies have largely concentrated on deep learning (DL) techniques, leading to a shortage of RUL prediction methods that utilize deep reinforcement learning (DRL). To further enhance application and research, this paper introduces a novel approach to RUL prediction based on DRL, specifically using a combination of Convolutional Neural Network-Bidirectional Long Short-Term Memory Network (CNN-BiLSTM) and the Deep Deterministic Policy Gradient (DDPG) algorithm. The proposed method reframes the conventional task of estimating RUL as a Markov decision process (MDP), effectively integrating the feature extraction capabilities of DL with the decision-making abilities of DRL. Initially, a hybrid CNN-BiLSTM is employed to establish an agent that can extract degradation features from raw signals. Subsequently, the DDPG algorithm within DRL is leveraged to develop the RUL prediction mechanism, completing the MDP by defining appropriate action spaces and reward functions. The agent, through repeated trials and optimization, learns to map the current operational state of the rolling bearing to its remaining service life. Validation analysis was performed on the intelligent maintenance systems (IMS) bearing dataset. The findings suggest that the DRL-based approach outperforms the current methodologies, demonstrating a superior performance in root mean square error (MSE) and MSE metrics. The predicted outcomes align more closely with the actual lifespan values.


Assuntos
Aprendizado Profundo , Redes Neurais de Computação , Algoritmos , Cadeias de Markov
3.
Mar Environ Res ; 201: 106707, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39205357

RESUMO

Ocean acidification (OA) interacts with multiple environmental drivers, such as temperature, nutrients, and ultraviolet radiation (UVR), posing a threat to marine primary producers. In this study, we conducted a quantitative meta-analysis of 1001 experimental assessments from 68 studies to examine the combined effects of OA and multiple environmental drivers (e.g., light, nutrient) on the biochemical compositions of marine primary producers. The results revealed significant positive effects of each environmental driver and their interactions with OA according to Hedge's d analysis. The results revealed significant positive effects of multiple environmental drivers and their interactions with OA. Additive effects dominated (71%), with smaller proportions of antagonistic (20%) and synergistic interactions (9%). The antagonistic interactions, although fewer, had a substantial impact, causing OA and other environmental drivers to interact antagonistically. Significant differences were observed among taxonomic groups: haptophytes and rhodophytes were negatively affected, while bacillariophytes were positively affected by OA. Our findings also indicated that the interactions between OA and multiple environmental drivers varied depending on specific type of the environmental driver, suggesting a modulating role of OA on the biochemical compositions of marine primary producers in response to global change. In summary, our study elucidates the complex interactions between OA and multiple environmental drivers on marine primary producers, highlighting the varied impacts on biochemical compositions and elemental stoichiometry.


Assuntos
Oceanos e Mares , Água do Mar , Água do Mar/química , Concentração de Íons de Hidrogênio , Monitoramento Ambiental , Organismos Aquáticos , Mudança Climática , Acidificação dos Oceanos
4.
Nat Commun ; 15(1): 7319, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-39183339

RESUMO

Non-direct antimicrobial cationic peptides (NDACPs) are components of the animal innate immune system. But their functions and association with antimicrobial peptides (AMPs) are incompletely understood. Here, we reveal a synergistic interaction between the AMP AW1 and the NDACP AW2, which are co-expressed in the frog Amolops wuyiensis. AW2 enhances the antibacterial activity of AW1 both in vitro and in vivo, while mitigating the development of bacterial resistance and eradicating biofilms. AW1 and AW2 synergistically damage bacterial membranes, facilitating cellular uptake and interaction of AW2 with the intracellular target bacterial genomic DNA. Simultaneously, they trigger the generation of ROS in bacteria, contributing to cell death upon reaching a threshold level. Moreover, we demonstrate that this synergistic antibacterial effect between AMPs and NDACPs is prevalent across diverse animal species. These findings unveil a robust and previously unknown correlation between AMPs and NDACPs as a widespread antibacterial immune defense strategy in animals.


Assuntos
Antibacterianos , Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Biofilmes , Sinergismo Farmacológico , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/metabolismo , Biofilmes/efeitos dos fármacos , Peptídeos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos/química , Antibacterianos/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Testes de Sensibilidade Microbiana , Ranidae/imunologia , Camundongos , Imunidade Inata/efeitos dos fármacos , Farmacorresistência Bacteriana/genética
5.
Anal Chim Acta ; 1319: 342966, 2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39122278

RESUMO

BACKGROUND: The abuse of 17ß-estradiol(E2) has aroused wide concern in environmental and biomedical fields, which severely affects the endocrine function of human and animals. Therefore, an ultrasensitive and accurate assay of E2 is critically important. Traditional chromatography or immunoassay techniques exhibited good sensitivity and selectivity, but expensive instruments and antibodies may pose cost and stability issues, as well as difficulties in meeting on-site detection requirements. Ultrasensitive, reliable, and on-site detection of E2 at trace level remains a challenge. Hence, developing a simple, ultrasensitive assay to simultaneously achieve accurate detection and rapid visual analysis of E2 is extremely crucial. RESULTS: We developed a versatile dual-mode photoelectrochemical (PEC) and colorimetric biosensor based on isothermal nucleic acid amplification strategy for the ultrasensitive and accurate detection of E2. The method modified titanium dioxide (TiO2) with tungsten selenide (WSe2) nanoflowers to synthesize WSe2/TiO2 heterostructures as a substrate for signal amplification and nanoprobe modification. Isothermal nucleic acid amplification strategy has been proven to be a powerful tool for strong signal amplification. The presence of a target triggered the nucleic acid amplification reaction, and produced a large amount of tDNA that competed with G-quadruplex immobilized on the electrode surface. The remaining G-quadruplex/hemin catalyzed the 4-chloro-1-naphthol (4-CN) to form biocatalytic precipitation (BCP) and ABTS-H2O2 chromogenic reaction, thus, the dual-mode platform was capable of achieving PEC-colorimetric ultrasensitive detection based on the catalytic activity of G-quadruplex/hemin DNAzyme. Within optimal conditions, the dual-mode biosensor exhibited a remarkable detection limit as low as 0.026 pM. SIGNIFICANCE: Benefiting from the superior performance of WSe2/TiO2 and the power signal amplification of isothermal nucleic acid amplification strategy, this aptasensor achieved the ultrasensitive detection of E2. The independent transmission paths of photoelectrochemical and colorimetric provide mutual support and flexible switching, significantly enhancing the overall sensitivity and accuracy of the detection strategy, which can meet the needs for E2 precise quantification and rapid on-site detection.


Assuntos
Técnicas Biossensoriais , Colorimetria , Técnicas Eletroquímicas , Eletrodos , Estradiol , Técnicas de Amplificação de Ácido Nucleico , Titânio , Titânio/química , Técnicas Biossensoriais/métodos , Técnicas Eletroquímicas/métodos , Estradiol/análise , Limite de Detecção , Processos Fotoquímicos , Compostos de Selênio/química , Humanos
6.
PLoS One ; 19(8): e0308808, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39133754

RESUMO

The Tendo Unit (TU) and GymAware (GA) are the two most frequently used linear transducers for assessing muscle power in older adults via the sit-to-stand (STS) test. Unlike TU, GA incorporates a sensor mechanism to correct for non-vertical movements, which may lead to systematic differences between devices. The aim of this study therefore was to compare GA to TU for measuring STS power in community-dwelling older adults. Community-dwelling adults (n = 51, aged ≥65 years, 61% female) completed a single chair stand, with peak power measured simultaneously using GA and TU. Participants also completed the pneumatic leg press, 8-Foot Up and Go (TUG) test, Short Physical Performance Battery (SPPB), and self-reported measures of physical function. Intraclass correlations (ICC) were used to assess agreement, and Pearson's correlations were used to assess correlations. The study protocol was prospectively registered on the Open Science Framework. In alignment with our pre-registered hypothesis, peak power demonstrated an ICC of 0.93 (95% CI: 0.88, 0.96). For secondary aims, both transducers showed a correlation greater than 0.8 compared to pneumatic leg press power. For physical performance outcomes, both TU and GA showed similar correlations, as hypothesized: SPPB (r = 0.29 for TU vs. 0.33 for GA), Chair Stands (r = -0.41 vs. -0.38), TUG Fast (r = -0.53 vs. -0.52), mobility questionnaire (r = 0.52 vs. 0.52) and physical function questionnaire (r = 0.44 vs. 0.43). GA and TU peak power showed a high degree of agreement and similar correlations with physical and self-reported performance measures, suggesting that both methods can be used for assessing STS power in older adults.


Assuntos
Força Muscular , Humanos , Idoso , Feminino , Masculino , Força Muscular/fisiologia , Postura Sentada , Transdutores , Idoso de 80 Anos ou mais , Posição Ortostática , Vida Independente , Músculo Esquelético/fisiologia
7.
Emerg Microbes Infect ; 13(1): 2389115, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39129566

RESUMO

Rabies is a lethal zoonotic disease that threatens human health. As the only viral surface protein, the rabies virus (RABV) glycoprotein (G) induces main neutralizing antibody (Nab) responses; however, Nab titre is closely correlated with the conformation of G. Virus-like particles (VLP) formed by the co-expression of RABV G and matrix protein (M) improve retention and antigen presentation, inducing broad, durable immune responses. RABV nucleoprotein (N) can elicit humoral and cellular immune responses. Hence, we developed a series of nucleoside-modified RABV mRNA vaccines encoding wild-type G, soluble trimeric RABV G formed by an artificial trimer motif (tG-MTQ), membrane-anchored prefusion-stabilized G (preG). Furthermore, we also developed RABV VLP mRNA vaccine co-expressing preG and M to generate VLPs, and VLP/N mRNA vaccine co-expressing preG, M, and N. The RABV mRNA vaccines induced higher humoral and cellular responses than inactivated rabies vaccine, and completely protected mice against intracerebral challenge. Additionally, the IgG and Nab titres in RABV preG, VLP and VLP/N mRNA groups were significantly higher than those in G and tG-MTQ groups. A single administration of VLP or VLP/N mRNA vaccines elicited protective Nab responses, the Nab titres were significantly higher than that in inactivated rabies vaccine group at day 7. Moreover, RABV VLP and VLP/N mRNA vaccines showed superior capacities to elicit potent germinal centre, long-lived plasma cell and memory B cell responses, which linked to high titre and durable Nab responses. In summary, our data demonstrated that RABV VLP and VLP/N mRNA vaccines could be promising candidates against rabies.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , Imunidade Celular , Imunidade Humoral , Vacina Antirrábica , Vírus da Raiva , Raiva , Vacinas de Partículas Semelhantes a Vírus , Animais , Vacina Antirrábica/imunologia , Vacina Antirrábica/administração & dosagem , Vacina Antirrábica/genética , Raiva/prevenção & controle , Raiva/imunologia , Vírus da Raiva/imunologia , Vírus da Raiva/genética , Camundongos , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Neutralizantes/sangue , Vacinas de Partículas Semelhantes a Vírus/imunologia , Vacinas de Partículas Semelhantes a Vírus/administração & dosagem , Vacinas de Partículas Semelhantes a Vírus/genética , Feminino , Vacinas de mRNA/imunologia , Camundongos Endogâmicos BALB C , Nucleosídeos/imunologia , Glicoproteínas/imunologia , Glicoproteínas/genética , Humanos , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Proteínas da Matriz Viral/imunologia , Proteínas da Matriz Viral/genética , Antígenos Virais/imunologia , Antígenos Virais/genética , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/genética , RNA Mensageiro/genética , RNA Mensageiro/imunologia
8.
Adv Sci (Weinh) ; 11(35): e2402074, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39033536

RESUMO

Application of aqueous zinc metal batteries (AZMBs) in large-scale new energy systems (NESs) is challenging owing to the growth of dendrites and frequent side reactions. Here, this study proposes the use of Panthenol (PB) as an electrolyte additive in AZMBs to achieve highly reversible zinc plating/stripping processes and suppressed side reactions. The PB structure is rich in polar groups, which led to the formation of a strong hydrogen bonding network of PB-H2O, while the PB molecule also builds a multi-coordination solvated structure, which inhibits water activity and reduces side reactions. Simultaneously, PB and OTF- decomposition, in situ formation of SEI layer with stable organic-inorganic hybrid ZnF2-ZnS interphase on Zn anode electrode, can inhibit water penetration into Zn and homogenize the Zn2+ plating. The effect of the thickness of the SEI layer on the deposition of Zn ions in the battery is also investigated. Hence, this comprehensive regulation strategy contributes to a long cycle life of 2300 h for Zn//Zn cells assembled with electrolytes containing PB additives. And the assembled Zn//NH4V4O10 pouch cells with homemade modules exhibit stable cycling performance and high capacity retention. Therefore, the proposed electrolyte modification strategy provides new ideas for AZMBs and other metal batteries.

9.
IEEE Trans Cybern ; PP2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959152

RESUMO

Hybridization plays a prominent role in bolstering the performance of optimization algorithms (OAs), yet designing efficient hybrid OAs tailored to intricate optimization problems persists as a formidable task. This article introduces a novel top-down methodology for the automated design of hybrid OAs, treating algorithm design as a meta-optimization problem. A general design template for collaboration-based hybrid OAs is developed, integrating a multitude of hybridization strategies for the first time. Besides, a mathematical model is built to formulate the meta-optimization problem of algorithm design. To address the meta-optimization challenge, an improved multifactorial evolutionary algorithm is proposed to automatically design efficient hybrid metaheuristics in a multitasking environment for the given instances with diverse features. To verify the effectiveness of the proposed design methodology, it is applied to the CEC2017 benchmark functions and the binary knapsack problem. Numerical results have demonstrated the feasibility and effectiveness of the proposed methodology for both continuous and combinatorial optimization benchmarks.

10.
Angew Chem Int Ed Engl ; : e202407928, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39022842

RESUMO

Although highly appealing for rapid access of molecular complexity, multi-functionalization of alkenes that allows incorporation of more than two functional groups remains a prominent challenge. Herein, we report a novel strategy that merges dipolar cycloaddition with photoredox promoted radical ring-opening remote C(sp3)-H functionalization, thus enabling a smooth 1,2,5-trifunctionalization of unactivated alkenes. A highly regioselective [3+2] cycloaddition anchors a reaction trigger onto alkene substrates. The subsequent halogen atom transfer (XAT) selectively initiates ring-opening process, which is followed by a series of 1,5-hydrogen atom transfer (1,5-HAT) and intermolecular fluorine atom transfer (FAT) events. With this method, site-selective introduction of three different functional groups is accomplished and a broad spectrum of valuable ß-hydroxyl-ε-fluoro-nitrile products are synthesized from readily available terminal alkenes.

11.
BMC Cancer ; 24(1): 877, 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39039516

RESUMO

BACKGROUND: Inetetamab is the first domestically developed innovative anti-HER2 monoclonal antibody in China, proven effective and safe in HER2-positive advanced breast cancer. However, its efficacy and safety in neoadjuvant treatment of HER2-positive locally advanced breast cancer (LABC) remain to be validated. METHODS: This prospective cohort study aimed to evaluate the efficacy and safety of inetetamab combined with pertuzumab, taxanes, and carboplatin (TCbIP) in neoadjuvant therapy for HER2-positive LABC, comparing it to data from patients treated with the TCbHP regimen (trastuzumab combined with pertuzumab, taxanes, and carboplatin) using propensity score matching (PSM). The primary endpoint was total pathological complete response (tpCR). Adverse events (AEs), objective response rate (ORR), and near-pCR were key secondary endpoints. RESULTS: Forty-four patients with clinical stage IIA-IIIC HER2-positive LABC were prospectively enrolled and treated with the TCbIP regimen. The tpCR rate among 28 patients who completed surgery was 60.7%, comparable to and slightly higher than the TCbHP group in PSM (60.7% vs. 53.6%, P = 0.510). The ORR was 96.4%, and the DCR reached 100.0%. The most common ≥ grade 3 AE was neutropenia (21.4% vs. 11.9%, P = 0.350). No significant reduction in left ventricular ejection fraction was observed, and no patient withdrew from treatment due to AEs. CONCLUSION: Neoadjuvant therapy with TCbIP showed good efficacy and safety in patients with HER2-positive LABC and might be another promising option for neoadjuvant treatment. TRIAL REGISTRATION: NCT05749016 (registration date: Nov 01, 2021).


Assuntos
Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama , Carboplatina , Terapia Neoadjuvante , Pontuação de Propensão , Receptor ErbB-2 , Taxoides , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Carboplatina/administração & dosagem , Carboplatina/uso terapêutico , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Estudos Prospectivos , Adulto , Receptor ErbB-2/metabolismo , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Taxoides/administração & dosagem , Taxoides/uso terapêutico , Idoso , Trastuzumab/uso terapêutico , Trastuzumab/administração & dosagem , Resultado do Tratamento
12.
Clin Breast Cancer ; 24(7): e593-e599, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38890023

RESUMO

BACKGROUND: The utilization of neoadjuvant chemotherapy (NAC) originated in the treatment of locally advanced breast cancer (BC). Our study is designed to elucidate the effects of NAC on patients with T1N0M0 triple-negative and HER-2 positive BC. METHODS: This study involved the selection of 10,614 patients diagnosed with T1N0M0 triple-negative and HER-2 positive breast cancer (BC) from the surveillance, epidemiology, and end results (SEER) database. To ascertain the impact of neoadjuvant chemotherapy (NAC) on T1a, T1b, and T1c N0M0 BC, we conducted multivariate Cox regression analyses. Similarly, we performed multivariate Cox regression analyses to compare the effects of neoadjuvant chemotherapy against adjuvant chemotherapy on T1N0M0 BC. The Kaplan-Meier method was employed to delineate survival curves for different molecular subtypes and clinical stages. RESULTS: The data results from the SEER database reveal a significant enhancement of overall survival (OS) in T1c BC patients as a result of NAC. For T1b BC patients, NAC does not present any significant effect. Contrarily, NAC seems to adversely impact the OS of T1a triple-negative BC patients. However, the prognosis comparison between neoadjuvant and adjuvant chemotherapy for T1N0M0 breast cancer did not show any significant difference, with the exception of T1a triple-negative BC. CONCLUSIONS: Patients with T1cN0M0 triple-negative and HER-2 positive BC may derive OS benefits from NAC. Additionally, NAC could be detrimental to T1a triple-negative BC.


Assuntos
Terapia Neoadjuvante , Receptor ErbB-2 , Programa de SEER , Neoplasias de Mama Triplo Negativas , Humanos , Feminino , Terapia Neoadjuvante/métodos , Receptor ErbB-2/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/mortalidade , Neoplasias de Mama Triplo Negativas/metabolismo , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto , Quimioterapia Adjuvante/métodos , Estadiamento de Neoplasias , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Prognóstico , Taxa de Sobrevida
13.
Materials (Basel) ; 17(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893805

RESUMO

To investigate the effects of nano-SiO2 (NS) and polyvinyl alcohol (PVA) fibers on the durability and mechanical properties of cementitious composites subjected to saline freeze-thaw cycling, a series of PVA fiber-reinforced cementitious composite (PFRCC) specimens were prepared using various fiber contents, and a series of NS and PVA fiber-reinforced cementitious composite (NPFRCC) specimens were prepared using various combinations of NS and fiber contents. Durability and fracture toughness tests were subsequently conducted on the specimens after different numbers of saline freeze-thaw cycles. The results indicate that the degradation of material properties can be divided into slow and accelerated damage stages before/after 50 freeze-thaw cycles. The durability and fracture toughness of the specimen series tended to increase, then decrease with increasing NS and PVA contents, suggesting optimum levels. When the PVA fiber content was 0.5%, PFRCC specimens had the best durability after saline freeze-thaw cycles; when the NS and PVA fiber contents were 1.0% and 0.5%, respectively, NPFRCC specimens had the best durability and fracture properties, and the initiation toughness, destabilization toughness, and fracture energy after 100 saline freeze-thaw cycles were 120.69%, 160.02%, and 451.31%, respectively. The results of this study may guide future exploration of the durability and mechanical properties of concrete subjected to freeze-thaw action.

14.
Rev Sci Instrum ; 95(6)2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38864724

RESUMO

Aiming at the problem that the rolling bearing fault data are difficult to obtain and that the traditional fault diagnosis method does not consider the signal uncertainty characteristics and the low accuracy of models in the process of rolling bearing fault, a fault diagnosis method based on simulation and experiment fusion drive is proposed. First, the dynamics simulation model of rolling bearings under different fault conditions is established to obtain the bearing fault simulation signals. Second, a sequence generative adversarial network is used to fuse the simulation and experimental data. Bearing vibration signals are often very uncertain, so considering the probability characteristics of fault signals, the probability box model under different fault states is constructed by the direct probability box modeling method, and its characteristic vectors are extracted. Finally, an extreme gradient boosting Tree model for fault diagnosis classification is constructed to compare and evaluate the classification and diagnosis effects of bearing states before and after data fusion. The results show that the proposed method has a good diagnostic effect and is suitable for solving the fault diagnosis problem under the condition of insufficient data.

15.
J Agric Food Chem ; 72(25): 14216-14228, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38860925

RESUMO

Two-component systems (TCSs) sensing and responding to various stimuli outside and inside cells are valuable resources for developing biosensors with synthetic biology applications. However, the use of TCS-based biosensors suffers from a limited effector spectrum, hypersensitivity, low dynamic range, and unwanted signal crosstalk. Here, we developed a tailor-made Escherichia coli whole-cell γ-aminobutyric acid (GABA) biosensor by engineering a chimeric GABA chemoreceptor PctC and TCS. By testing different TCSs, the chimeric PctC/PhoQ showed the response to GABA. Chimera-directed evolution and introduction of the insulated chimeric pair PctC/PhoQ*PhoP* produced biosensors with up to 3.50-fold dynamic range and good orthogonality. To further enhance the dynamic range and lower the basal leakage, three strategies, engineering of PhoP DNA binding sites, fine-tuning reporter expression by optimizing transcription/translation components, and a tobacco etch virus protease-controlled protein degradation, were integrated. This chimeric biosensor displayed a low basal leakage, a large dynamic range (15.8-fold), and a high threshold level (22.7 g L-1). Finally, the optimized biosensor was successfully applied in the high-throughput microdroplet screening of GABA-overproducing Corynebacterium glutamicum, demonstrating its desired properties for extracellular signal biosensing.


Assuntos
Técnicas Biossensoriais , Proteínas de Escherichia coli , Escherichia coli , Ácido gama-Aminobutírico , Técnicas Biossensoriais/métodos , Técnicas Biossensoriais/instrumentação , Ácido gama-Aminobutírico/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo
16.
Inorg Chem ; 63(28): 12721-12729, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38937975

RESUMO

High-entropy diborides (HEDBs) have gained significant attention in industrial applications due to their vast composition space and tunable properties. We propose a solid solution reaction at high temperatures and pressures that successfully synthesized and sintered a novel, dense, and phase-pure HEDB (V0.2Nb0.2Ta0.2Cr0.2W0.2)B2. A high asymptotic Vickers hardness of 26.3 ± 0.6 GPa and a bulk modulus of 320.5 ± 10.6 GPa were obtained. Additionally, we investigated the thermal oxidation process using TG-DSC from room temperature to 1500 °C and explored the phase stability of HEDBs under high-pressure conditions through in situ high-pressure synchrotron radiation X-ray diffraction. We analyzed the formation of lattice distortion, chemical bonding, and band structure in (V0.2Nb0.2Ta0.2Cr0.2W0.2)B2 using first-principles calculations. Surprisingly, we found that the predominant distortion in diborides occurs in the boron layer, supported by ELF. This may be due to uneven electron transfer rather than a straightforward correlation with the atomic radius. These results provide a novel synthesis process and additional experimental data on the mechanical and thermal properties and high-pressure phase stability of HEDBs. Our study offers further insights into the microscopic structure of lattice distortion in HEDBs, which could prove crucial for the selection and design of engineering advanced HEDBs.

17.
Plant J ; 119(4): 2001-2020, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38943614

RESUMO

While it is known that increased dissolved CO2 concentrations and rising sea surface temperature (ocean warming) can act interactively on marine phytoplankton, the ultimate molecular mechanisms underlying this interaction on a long-term evolutionary scale are relatively unexplored. Here, we performed transcriptomics and quantitative metabolomics analyses, along with a physiological trait analysis, on the marine diatom Thalassiosira weissflogii adapted for approximately 3.5 years to warming and/or high CO2 conditions. We show that long-term warming has more pronounced impacts than elevated CO2 on gene expression, resulting in a greater number of differentially expressed genes (DEGs). The largest number of DEGs was observed in populations adapted to warming + high CO2, indicating a potential synergistic interaction between these factors. We further identified the metabolic pathways in which the DEGs function and the metabolites with significantly changed abundances. We found that ribosome biosynthesis-related pathways were upregulated to meet the increased material and energy demands after warming or warming in combination with high CO2. This resulted in the upregulation of energy metabolism pathways such as glycolysis, photorespiration, the tricarboxylic acid cycle, and the oxidative pentose phosphate pathway, as well as the associated metabolites. These metabolic changes help compensate for reduced photochemical efficiency and photosynthesis. Our study emphasizes that the upregulation of ribosome biosynthesis plays an essential role in facilitating the adaptation of phytoplankton to global ocean changes and elucidates the interactive effects of warming and high CO2 on the adaptation of marine phytoplankton in the context of global change.


Assuntos
Dióxido de Carbono , Diatomáceas , Diatomáceas/metabolismo , Diatomáceas/genética , Diatomáceas/fisiologia , Dióxido de Carbono/metabolismo , Fitoplâncton/genética , Fitoplâncton/fisiologia , Fitoplâncton/metabolismo , Adaptação Fisiológica , Transcriptoma , Aquecimento Global , Fotossíntese , Metabolômica
18.
ACS Appl Mater Interfaces ; 16(21): 27381-27393, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38752270

RESUMO

Using hybrid density functional theory calculations, we systematically study the biaxial strain and electric field modulated electronic properties of g-ZnO/SnS2, g-ZnO/SnSe2, and g-ZnO/SnSSe S-scheme van der Waals heterostructures (vdWHs). g-ZnO/SnS2 and g-ZnO/SnSSe are found to be promising photocatalysts for water splitting with high solar-to-hydrogen efficiencies, even under acidic, alkaline, and high-stress conditions. The strain effect on the bandgaps of g-ZnO/SnXY is explained in detail according to the correlation between geometry structure and orbital hybridization of SnXY, which could help understand the strain-induced band structure evolutions in other SnXY (X, Y = S, Se)-based vdWHs. It is surprising that under an external electric field, g-ZnO/SnS2, g-ZnO/SnSe2, and g-ZnO/SnSSe can offer the occupied nearly free-electron (NFE) states. In many materials, NFE states are usually unoccupied and is not conducive to the charge transport. The NFE state in g-ZnO/SnSe2 is the most sensitive to the electric field and might be promising electron transport channel in nanoelectronic devices. g-ZnO/SnSe2 might also have application potential in gas sensors and high-temperature superconductors.

19.
Microbiome ; 12(1): 90, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750595

RESUMO

BACKGROUND: Gut microbiome metabolites are important modulators of host health and disease. However, the overall metabolic potential of the gut microbiome and interactions with the host organs have been underexplored. RESULTS: Using stable isotope resolved metabolomics (SIRM) in mice orally gavaged with 13C-inulin (a tracer), we first observed dynamic enrichment of 13C-metabolites in cecum contents in the amino acids and short-chain fatty acid metabolism pathways. 13C labeled metabolites were subsequently profiled comparatively in plasma, liver, brain, and skeletal muscle collected at 6, 12, and 24 h after the tracer administration. Organ-specific and time-dependent 13C metabolite enrichments were observed. Carbons from the gut microbiome were preferably incorporated into choline metabolism and the glutamine-glutamate/GABA cycle in the liver and brain, respectively. A sex difference in 13C-lactate enrichment was observed in skeletal muscle, which highlights the sex effect on the interplay between gut microbiome and host organs. Choline was identified as an interorgan metabolite derived from the gut microbiome and fed the lipogenesis of phosphatidylcholine and lysophosphatidylcholine in host organs. In vitro and in silico studies revealed the de novo synthesis of choline in the human gut microbiome via the ethanolamine pathway, and Enterococcus faecalis was identified as a major choline synthesis species. These results revealed a previously underappreciated role for gut microorganisms in choline biosynthesis. CONCLUSIONS: Multicompartmental SIRM analyses provided new insights into the current understanding of dynamic interorgan metabolite transport between the gut microbiome and host at the whole-body level in mice. Moreover, this study singled out microbiota-derived metabolites that are potentially involved in the gut-liver, gut-brain, and gut-skeletal muscle axes. Video Abstract.


Assuntos
Isótopos de Carbono , Microbioma Gastrointestinal , Metabolômica , Músculo Esquelético , Animais , Camundongos , Metabolômica/métodos , Isótopos de Carbono/metabolismo , Masculino , Músculo Esquelético/metabolismo , Feminino , Encéfalo/metabolismo , Fígado/metabolismo , Colina/metabolismo , Camundongos Endogâmicos C57BL , Humanos , Ácidos Graxos Voláteis/metabolismo
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