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1.
Adv Sci (Weinh) ; : e2402114, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38896802

RESUMO

Spinal cord injury (SCI) is a severe neurological condition that frequently leads to significant sensory, motor, and autonomic dysfunction. This study sought to delineate the potential mechanistic underpinnings of extracellular vesicles (EVs) derived from ginsenoside Rg1-pretreated neuronal cells (Rg1-EVs) in ameliorating SCI. These results demonstrated that treatment with Rg1-EVs substantially improved motor function in spinal cord-injured mice. Rg1-EVs enhance microglial polarization toward the M2 phenotype and repressed oxidative stress, thereby altering immune responses and decreasing inflammatory cytokine secretion. Moreover, Rg1-EVs substantially diminish reactive oxygen species accumulation and enhanced neural tissue repair by regulating mitochondrial function. Proteomic profiling highlighted a significant enrichment of MYCBP2 in Rg1-EVs, and functional assays confirmed that MYCBP2 knockdown counteracted the beneficial effects of Rg1-EVs in vitro and in vivo. Mechanistically, MYCBP2 is implicated in the ubiquitination and degradation of S100A9, thereby promoting microglial M2-phenotype polarization and reducing oxidative stress. Overall, these findings substantiated the pivotal role of Rg1-EVs in neuronal protection and functional recovery following SCI through MYCBP2-mediated ubiquitination of S100A9. This research offers novel mechanistic insights into therapeutic strategies against SCI and supports the clinical potential of Rg1-EVs.

2.
Dalton Trans ; 53(24): 10142-10149, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38818546

RESUMO

The development of excellent bifunctional electrocatalysts is an effective way to promote the industrial application of electrolytic water. In this work, a free-standing W-doped cobalt selenide (W-CoSe300/NF) electrocatalyst with a snowflake-like structure supported on nickel foam was prepared by a hydrothermal-selenization strategy. Benefiting from the high specific surface area of the 3D snowflake-like structure and the regulation of tungsten doping on the electronic structure of the metal active center, W-CoSe300/NF shows remarkable electrocatalytic water decomposition performance. In 1.0 M KOH, the W-CoSe300/NF electrocatalyst achieved an efficient HER and OER at a current density of 50 mA cm-2 with overpotentials as low as 84 mV and 283 mV, respectively. More importantly, W-CoSe300/NF acts as both the anode and cathode of the electrolytic tank, requiring only a potential of 1.54 V to obtain 10 mA cm-2 and can operate continuously for more than 120 hours at this current density. This study proposes a new way for the design of high efficiency and affordable bifunctional electrocatalysts.

3.
Int J Biol Macromol ; 271(Pt 1): 132693, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38806086

RESUMO

In this study, a novel double-layer slow-release fertilizer (SRF) was developed utilizing stearic acid (SA) as a hydrophobic inner coating and a blend of starch phosphate carbamate (abbreviated as SPC) and polyvinyl alcohol (PVA) as a hydrophilic outer coating (designated as SPCP). The mass ratios of SPC and PVA in the SPCP matrices were systematically optimized by comprehensively checking the water absorbency, water contact angle (WCA), water retention property (WR), and mechanical properties such as percentage elongation at break and tensile strength with FTIR, XRD, EDS, and XPS techniques, etc. Moreover, the optimal SPCP/5:5 demonstrated superior water absorbency with an 80.2 % increase for the total mass compared to natural starch/PVA(NSP), along with desirable water retention capacity in the soil, exhibiting a weight loss of only 48 % over 13 d. Relative to pure urea and SA/NSPU/5:5, SA/SPCPU/5:5 released 50.3 % of its nutrient within 15 h, leading to nearly complete release over 25 h in the aqueous phase, while only 46.6 % of urea was released within 20 d in soil, extending to approximately 30 d. The slow release performance of urea reveals that the diffusion rate of urea release shows a significant decrease with an increase in coating layers. Consequently, this work demonstrated a prospective technology for the exploration of environmentally friendly SRF by integrating biodegradable starch derivatives with other polymers.


Assuntos
Preparações de Ação Retardada , Fertilizantes , Álcool de Polivinil , Amido , Ureia , Água , Amido/química , Álcool de Polivinil/química , Ureia/química , Água/química , Biodegradação Ambiental , Interações Hidrofóbicas e Hidrofílicas , Solo/química
4.
Commun Biol ; 7(1): 539, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714886

RESUMO

Intervertebral disc degeneration (IDD) is a highly prevalent musculoskeletal disorder affecting millions of adults worldwide, but a poor understanding of its pathogenesis has limited the effectiveness of therapy. In the current study, we integrated untargeted LC/MS metabolomics and magnetic resonance spectroscopy data to investigate metabolic profile alterations during IDD. Combined with validation via a large-cohort analysis, we found excessive lipid droplet accumulation in the nucleus pulposus cells of advanced-stage IDD samples. We also found abnormal palmitic acid (PA) accumulation in IDD nucleus pulposus cells, and PA exposure resulted in lipid droplet accumulation and cell senescence in an endoplasmic reticulum stress-dependent manner. Complementary transcriptome and proteome profiles enabled us to identify solute carrier transporter (SLC) 43A3 involvement in the regulation of the intracellular PA level. SLC43A3 was expressed at low levels and negatively correlated with intracellular lipid content in IDD nucleus pulposus cells. Overexpression of SLC43A3 significantly alleviated PA-induced endoplasmic reticulum stress, lipid droplet accumulation and cell senescence by inhibiting PA uptake. This work provides novel integration analysis-based insight into the metabolic profile alterations in IDD and further reveals new therapeutic targets for IDD treatment.


Assuntos
Senescência Celular , Estresse do Retículo Endoplasmático , Degeneração do Disco Intervertebral , Gotículas Lipídicas , Núcleo Pulposo , Ácido Palmítico , Núcleo Pulposo/metabolismo , Núcleo Pulposo/efeitos dos fármacos , Núcleo Pulposo/patologia , Núcleo Pulposo/citologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Ácido Palmítico/metabolismo , Ácido Palmítico/farmacologia , Senescência Celular/efeitos dos fármacos , Degeneração do Disco Intervertebral/metabolismo , Degeneração do Disco Intervertebral/patologia , Humanos , Gotículas Lipídicas/metabolismo , Masculino , Feminino , Adulto , Pessoa de Meia-Idade
5.
J Pediatr (Rio J) ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38604242

RESUMO

OBJECTIVE: Monitoring the disease status of Epstein-Barr virus (EBV)-related hemophagocytic lymphohistiocytosis (HLH) patients is crucial. This study aimed to investigate the different strategies and outcomes of patients with EBV-HLH and re-elevated EBV-DNA. METHOD: A retrospective analysis was conducted on 20 patients diagnosed with EBV-HLH. Clinical features, laboratory tests, treatments, plasma EBV-DNA levels, and outcomes were assessed. Three cases were highlighted for detailed analysis. RESULTS: Nine of the 20 patients had a re-elevation of EBV-DNA during treatment, and 55.5 % (5/9) experienced relapses. Patients with persistently positive plasma EBV-DNA (n = 4) and those with re-elevated EBV-DNA after conversion (n = 9) showed a significantly higher relapse rate compared to those with persistently negative EBV-HLH (n = 7) (p < 0.05). Among the highlighted cases, Case 1 exhibited plasma EBV-DNA re-elevation after four weeks of treatment without relapse, maintaining stability with the original treatment regimen, and eventually, his plasma EBV-DNA turned negative. In Case 2, plasma EBV-DNA was elevated again with a recurrence of HLH after L-DEP. Consequently, she underwent allogeneic hematopoietic stem cell transplantation and eventually achieved complete remission (CR) with negative plasma EBV-DNA. Case 3 experienced plasma EBV-DNA re-elevation after L-DEP but remained in CR, discontinuing chemotherapy without relapse. CONCLUSION: The re-elevation of plasma EBV-DNA during EBV-HLH treatment poses challenges in determining disease status and treatment strategies. Optimal management decisions require a combination of the level of elevated EBV-DNA, the intensity of hyperinflammation, and the patient's immune function.

6.
J Colloid Interface Sci ; 667: 237-248, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38636225

RESUMO

Traditional phase engineering enhances conductivity or activity by fully converting electrocatalytic materials into either a crystalline or an amorphous state, but this approach often faces limitations. Thus, a practical solution entails balancing the dynamic attributes of both phases to maximize an electrocatalyst's functionality is urgently needed. Herein, in this work, Co/Co2C crystals have been assembled on the amorphous N, S co-doped porous carbon (NSPC) through hydrothermal and calcination processes. The stable biphase structure and amorphous/crystalline (A/C) interface enhance conductivity and intrinsic activity. Moreover, the adsorption ability of water molecules and intermediates is improved significantly attributed to the rich oxygen-containing groups, unsaturated bonds, and defect sites of NSPC, which accelerates proton-coupled electron transfer (PCET) and overall water splitting. Consequently, A/C-Co/Co2C/NSPC (Co/Co2C/NSPC with amorphous/crystalline interface) exhibits outstanding behavior for oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), requiring the overpotential of 240.0 mV and 70.0 mV to achieve 10 mA cm-2. Moreover, an electrolyzer assembled by A/C-Co/Co2C/NSPC-3 (anode) and A/C-Co/Co2C/NSPC-2 (cathode) demonstrates a low drive voltage of 1.54 V during overall water splitting process. Overall, this work has pioneered the coexistence of crystalline/amorphous phases in electrocatalysts and provided new insights into phase engineering.

7.
Medicine (Baltimore) ; 103(11): e37545, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489690

RESUMO

Observational studies have suggested that there may be a connection between systemic lupus erythematosus (SLE) and a higher likelihood of developing urological cancers, although the exact cause-effect relationship is still unclear. This study therefore investigated the causal relationship between SLE and urological cancers using the Mendelian randomization (MR) approach. Our primary MR analysis involved using the inverse variance weighted method, which employed an inverse-variance-weighted approach, to examine the causal relationship between SLE and urological conditions. In addition, we performed various sensitivity analyses, such as MR-Egger regression, tests for heterogeneity, and leave-one-out sensitivity tests, to assess the reliability of our results. The findings from our analysis using Two-Sample MR showed that genetically predicted SLE was linked to a reduced likelihood of developing renal cell carcinoma (RCC) (odds ratio = 0.9996, 95% confidence interval = 0.9993-0.9999, P value = .0159). These results suggest a possible protective impact of SLE against RCC. Nevertheless, no substantial correlation was detected between SLE and the likelihood of developing bladder cancer or prostate cancer. Collectively, these findings offer significant fresh perspectives on the possible correlation between SLE and genitourinary malignancies, specifically RCC, which will provide ideas and basis for the treatment of RCC.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Lúpus Eritematoso Sistêmico , Masculino , Humanos , Carcinoma de Células Renais/epidemiologia , Carcinoma de Células Renais/genética , Análise da Randomização Mendeliana , Reprodutibilidade dos Testes , Lúpus Eritematoso Sistêmico/genética , Neoplasias Renais/genética , Estudo de Associação Genômica Ampla , Polimorfismo de Nucleotídeo Único
8.
BMC Pediatr ; 24(1): 28, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38191334

RESUMO

BACKGROUND: Pediatric myelodysplastic syndromes (MDS) are rare disorders with an unrevealed pathogenesis. Our aim is to explore the role of genetic factors in the pathogenesis of MDS in children with different outcomes and to discover the correlation between genetic features and clinical outcomes as well as disease characteristics. METHODS: We conducted an analysis of archived genetic data from 26 patients diagnosed with pediatric MDS at our institution between 2015 and 2021, examining the association between different genetic characteristics and clinical manifestations as well as prognosis. Additionally, We presented three cases with distinct genetic background and outcomes as examples to elaborate the role of genetic factors in pediatric MDS with different prognoses. RESULTS: Genetic variations were detected in 13 out of the 26 patients, including 8 patients with co-occurrence of somatic and germline mutations (CSGMs) and 5 patients with somatic mutations alone. Our analysis revealed that advanced MDS (4/8, 50% vs. 1/5, 20% and 4/11, 36.4%), PD (3/8, 37.5% vs. 1/5, 20% and 1/11 9.1%), and TD (6/8, 75% vs. 2/5, 40% and 2/11, 18.2%) were more common in patients with CSGMs than those with somatic mutations alone or without any mutations. We also found out in our study that 8 patients with CSGMs had evidently different clinical outcomes, and we presented 3 of them as examples for elaboration. Case 1 with germline and somatic mutations of unknown significance had a relatively slow disease course and a good prognosis. Case 2 with compound heterozygous germline SBDS variants and somatic mutations like del20q had a stable disease course and a reversed outcome. Case 3 with a germline GATA2 variant and somatic mutations including - 7 had a rapidly progressive disease course and a worst prognosis. CONCLUSION: Our findings indicate that genetic background of pediatric MDS is closely linked with disease characteristics as well as outcomes and that CSGMs may lead to disease progression. It should be emphasized that the interaction between certain germline variants and somatic mutations, such as SBDS and del20q, may result in hematopoietic stem cell adaptation (improved hematopoiesis) and reversed clinical outcomes, which can facilitate the development of targeted therapy.


Assuntos
Instalações de Saúde , Síndromes Mielodisplásicas , Humanos , Criança , Progressão da Doença , Mutação , Síndromes Mielodisplásicas/diagnóstico , Síndromes Mielodisplásicas/genética , Doenças Raras
9.
BMC Infect Dis ; 24(1): 13, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166757

RESUMO

BACKGROUND: To assess the value of contrast-enhanced ultrasound (CEUS) in the diagnosis of tuberous vas deferens tuberculosis (VD TB) and improve the positive diagnostic rate of VD TB. METHODS: CEUS and routine ultrasound (US) images of 17 patients with tuberous VD TB confirmed by surgery, pathology, or laboratory semen examination were retrospectively analyzed and summarized, and the positive rates of both imaging techniques were compared. RESULTS: The 19 VD lesions of the 17 patients were divided into two types according to the CEUS findings: Type I and Type II, and type II was divided into Types IIa, IIb, and IIc. Of the nodules with transverse diameters > 1 cm, 100% presented as type II. Of the nodules with transverse diameters < 1 cm, 37.5% (3/8) presented as type I and 62.5% (5/8) presented as type II. The sonographic manifestations of tuberous VD TB were hypoechoic and mixed echoic. The positive diagnostic rate was 89.5% for CEUS and 68.4% for US, but the difference was not significant (χ2 = 2.533; P = 0.111). CONCLUSIONS: CEUS was able to show the blood supply characteristics of tuberous VD TB, the internal necrosis of nodules was more easily observed by CEUS than by routine US, which is helpful for the diagnosis of tuberous VD TB.


Assuntos
Meios de Contraste , Ducto Deferente , Masculino , Humanos , Estudos Retrospectivos , Ultrassonografia/métodos , Necrose
10.
Epidemiol Infect ; 152: e28, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38287476

RESUMO

Lymph node tuberculosis is particularly common in regions with a high tuberculosis burden, and it has a great risk of rupture. This study aims to investigate the utility of ultrasound multimodal imaging in predicting the rupture of cervical tuberculous lymphadenitis (CTL). 128 patients with unruptured CTL confirmed by pathology or laboratory tests were included. Various ultrasonic image features, including long-to-short-axis ratio (L/S), margin, internal echotexture, coarse calcification, Color Doppler Flow Imaging (CDFI), perinodal echogenicity, elastography score, and non-enhanced area proportion in contrast-enhanced ultrasound (CEUS), were analyzed to determine their predictive value for CTL rupture within a one-year follow-up period. As a result, L/S (P < 0.001), margin (P < 0.001), internal echotexture (P < 0.001), coarse calcification (P < 0.001), perinodal echogenicity (P < 0.001), and the area of non-enhancement in CEUS (P < 0.001) were identified as significant imaging features for predicting CTL rupture. The prognostic prediction showed a sensitivity of 89.29%, specificity of 100%, accuracy of 95.31%, respectively. Imaging findings such as L/S < 2, unclear margin, heterogeneous internal echotexture, perinodal echogenicity changed, and non-enhancement area in CEUS > 1/2, are indicative of CTL rupture, while coarse calcification in the lymph nodes is associated with a favorable prognosis.


Assuntos
Pescoço , Tuberculose dos Linfonodos , Humanos , Pescoço/diagnóstico por imagem , Pescoço/patologia , Tuberculose dos Linfonodos/diagnóstico por imagem , Tuberculose dos Linfonodos/patologia , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Ultrassonografia/métodos , Imagem Multimodal
11.
Biomol Biomed ; 24(2): 323-336, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-37540586

RESUMO

Globally, pancreatic cancer is recognized as one of the deadliest malignancies that lacks effective targeted therapies. This study aims to explore the role of cyclin I-like protein (CCNI2), a homolog of cyclin I (CCNI), in the progression of pancreatic cancer, thereby providing a theoretical basis for its treatment. Firstly, the expression of CCNI2 in pancreatic cancer tissues was determined through immunohistochemical staining. The biological role of CCNI2 in pancreatic cancer cells was further assessed using both in vitro and in vivo loss/gain-of-function assays. Our data revealed that CCNI2 expression was abnormally elevated in pancreatic cancer, and clinically, increased CCNI2 expression generally correlated with reduced overall survival. Functionally, CCNI2 contributed to the malignant progression of pancreatic cancer by promoting the proliferation and migration of tumor cells. Consistently, in vivo experiments verified that CCNI2 knockdown impaired the tumorigenic ability of pancreatic cancer cells. Moreover, the addition of phosphatidylinositol 3-kinase (PI3K) inhibitors could partially reverse the promoting effect of CCNI2 on the malignant phenotypes of pancreatic cancer cells. CCNI2 promoted pancreatic cancer through PI3K/protein kinase B (AKT) signaling pathway, indicating its potential as a prognostic marker and therapeutic target for pancreatic cancer.


Assuntos
Neoplasias Pancreáticas , Proteínas Proto-Oncogênicas c-akt , Humanos , Proteínas Proto-Oncogênicas c-akt/genética , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/genética , Ciclina I/metabolismo , Proliferação de Células/genética , Transdução de Sinais , Neoplasias Pancreáticas/genética
12.
Am J Physiol Cell Physiol ; 326(2): C386-C399, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38105759

RESUMO

Nucleus pulposus cell (NPC) senescence is a major cause of intervertebral disc degeneration (IVDD). Oxidative stress and reactive oxygen species (ROS) play critical roles in regulating cell senescence. Selenophosphate synthetase 1 (SEPHS1) was reported to play an important role in mitigating oxidative stress in an osteoarthritis (OA) model by reducing the production of ROS, thereby, delaying the occurrence and development of osteoarthritis. In this study, we explored the, hitherto unknown, role of SEPHS1 in IVDD in vitro and in vivo using an interleukin-1ß (IL-1ß)-induced NPC senescence model and a rat needle puncture IVDD model, respectively. SEPHS1 delayed NPC senescence in vitro by reducing ROS production. Age-related dysfunction was also ameliorated by the overexpression of SEPHS1 and inhibition of the Hippo-Yap/Taz signaling pathway. In vivo experiments revealed that the overexpression of SEPHS1 and inhibition of Hippo-Yap/Taz alleviated IVDD in rats. Moreover, a selenium (Se)-deficient diet and lack of SEPHS1 synergistically aggravated IVDD progression. Taken together, our results demonstrate that SEPHS1 plays a significant role in NPC senescence. Overexpression of SEPHS1 and inhibition of Hippo-Yap/Taz can delay NPC senescence, restore the balance of extracellular matrix metabolism, and attenuate IVDD. SEPHS1 could be a promising therapeutic target for IVDD.NEW & NOTEWORTHY Selenophosphate synthetase 1 (SEPHS1) deficiency leads to an increase in reactive oxygen species levels and in the subsequent activation of the Hippo-Yap/Taz signaling pathway. In the rat model of intervertebral disc degeneration (IVDD), overexpression of SEPHS1 and inhibition of Hippo-YAP/Taz mitigated the progression of disc degeneration indicating the involvement of SEPHS1 in IVDD. SEPHS1 is a promising therapeutic target for IVDD.


Assuntos
Degeneração do Disco Intervertebral , Núcleo Pulposo , Osteoartrite , Ratos , Animais , Degeneração do Disco Intervertebral/genética , Núcleo Pulposo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Senescência Celular , Osteoartrite/metabolismo
13.
Environ Manage ; 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38038761

RESUMO

Global ecosystem services (ESs) are experiencing a significant decline, necessitating the development of robust environmental governance policies. To address the lack of integrated planning with heavy industry as the research object and a lack of knowledge of ES trade-offs and synergies in China's ecological and environmental governance. In this study, the spatial and temporal variations of four ESs (water yield (WY), soil conservation (SC), carbon storage (CS), and habitat quality (HQ)) were determined in the study area of Liaoning Province. Explore the mechanisms that shape ecosystem service trade-offs and synergies and the factors that influence them. Spearman's correlation and difference analyses were proposed to determine the spatial and temporal distributions of trade-offs and synergistic relationships among ESs. In addition, we constructed a multiscale geo-weighted regression (MGWR) model to investigate driver spatial heterogeneity affecting trade-offs and synergies. The results revealed that (1) In the study area, ESs were on the rise in Liaoning Province. (2) Temporally, ESs were overwhelmingly dominated by synergies; at the spatial scale, ESs were dominated by trade-offs of varying degrees, with the area of synergy between WY and SC being the highest. (3) ESs demonstrated spatial heterogeneity in intensity and were more impacted by natural factors such as vegetation cover, elevation, and precipitation than by characteristics related to human activity. This study helps improve understanding of the interactions and dependencies among ESs and can provide a reference for ecological governance and improvements in Liaoning Province.

14.
Sensors (Basel) ; 23(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836853

RESUMO

Segmental stress during the construction process plays a pivotal role in assessing the safety and quality of shield tunnels. Fiber Bragg grating (FBG) sensing technology has been proposed for tunnel segment stress monitoring. A laboratory test was conducted to validate the reliable strain measurement of FBG sensors. The field in situ monitoring of a sewerage shield tunnel was carried out to examine the longitudinal and circumferential stresses experienced by the segments throughout the construction phase. The cyclic fluctuations in stress were found to be synchronized with the variations in shield thrust. A comparison was made between the longitudinal and circumferential stress variations observed during the shield-driving and segment-assembly processes. Additionally, the time required for the grouting to reach its full curing strength was estimated, revealing its impact on the stress levels and range of the pipe segment. The findings of this study offer an enhanced understanding of the stress state and health condition of small-diameter shield tunnels, which can help in optimizing the design and construction process of tunnel segments, as well.

15.
Materials (Basel) ; 16(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37834533

RESUMO

As complex and heterogeneous materials, the mechanical properties of rocks are still in need of further investigation regarding the mechanisms of the effects of water. In engineering projects such as goaf foundation treatment and ecological restoration, it is particularly important to describe the fracturing process of non-uniform water-containing sandstone media. The study utilized the theory of continuum mechanics to adopt an elastoplastic strain-softening constitutive relationship and develop a numerical model for analyzing the uniaxial compressive strength and failure characteristics of non-uniform water-containing sandstone. The results indicate that, compared with the reference rock sample, the shorter the capillary path of water entering the rock sample's internal pores or the larger the contact area with water, the shorter the time required for the rock sample to be saturated. Increasing the water content causes a rapid decline in the rock sample's elastic modulus and intensifies its brittleness. Group D2 and D3 samples exhibited a decrease in average peak strength to 70.4% and 62.1%, respectively, along with a corresponding decrease in the elastic modulus to 90.78% and 76.55%, indicating significant strain softening. While the failure mode of the rock sample remains consistent across different water contents, the homogeneity of failure shows significant variation. Increasing volumetric water content raises the likelihood of interconnecting cracks between rock samples, resulting in a progressive decline in macroscopic mechanical properties such as peak strength, critical strain, and elastic modulus. This research is significant in advancing the theory and construction technology for ecological restoration in goaf areas.

16.
Opt Express ; 31(16): 26517-26534, 2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37710511

RESUMO

At hypersonic velocities, the turbulent flow field generated by an aircraft, along with its temperature distribution, leads to significant aerodynamic optical effects that severely impede the performance of internal optical systems. This study proposes a method for analyzing the temporal characteristics of imaging degradation in a detector window infrared imaging system under different field angles of hypersonic velocity. Based on heat transfer theory, a method for solving the transient temperature field in the optical window of a high-speed aircraft is derived and established, considering unsteady thermal conduction-radiation coupling. Additionally, an optical window radiation tracing method is introduced, which directly determines the initial direction vector of light reaching the detector. This method reduces the workload of radiation transmission, significantly enhancing the efficiency of radiation calculations. The time characteristics of image degradation caused by aero-optical effects in high-speed aircraft are analyzed using metrics such as peak signal-to-noise ratio, wave aberration, and point diffusion function. The results demonstrate that as working time increases and the viewing angle widens, the impact of aero-optics on the aircraft imaging system becomes more severe. Moreover, compared to the aerodynamic light transmission effect, the aerodynamic thermal radiation effect has a more detrimental influence on imaging quality.

17.
J Chem Phys ; 159(8)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37610018

RESUMO

Developing dyes with high open-circuit photovoltage (Voc) is a vital strategy to improve the power conversion efficiency (PCE) of co-sensitized solar cells (co-DSSCs). Herein, three organic fluorine-containing dyes [YY-ThP(3F), YY-ThP(2F), and YY-ThP(26F)] are designed and synthesized for investigating the fluorine-induced effect on photophysical and photovoltaic performances. Consequently, this effect can significantly broaden the UV-vis absorption spectra of dyes but fail to improve the light-harvesting capability of DSSCs. Strikingly, YY-ThP(3F), featuring 3-position fluorine substitution to cyanoacrylic acid, yields a relatively high Voc compared to the corresponding fluorine-free dye (YY-ThP). Furthermore, the co-sensitization of YY-ThP+YY-ThP(3F) achieves a remarkably high PCE and long-term stability. This work implies that the combination of judicious molecular engineering and co-sensitization is a promising strategy for highly efficient and stable DSSCs.

18.
Nanotechnology ; 34(46)2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37567166

RESUMO

In this work, a novel nitrogen-phosphorus co-doped carbon quantum dots (N, P-CQDs) hydrogel was developed utilizing the as-synthesized N, P-CQDs and acrylamide (AM) with the existence of ammonium persulfate and N, N'-methylene bisacrylamide (N-MBA). In consistent with pure N, P-CQDs, the N, P-CQDs hydrogel also shows a dramatic fluorescence property with maximum emission wavelength of 440 nm, which can also be quenched after adsorbing iron ions (Fe3+). When the concentration of Fe3+is 0-6 mmol l-1, a better linear relationship between Fe3+concentration and the fluorescence intensities can be easily obtained. Additionally, the N, P-CQDs hydrogel exhibits better recyclability. This confirms that the N, P-CQDs hydrogel can be used for adsorbing and detecting Fe3+in aqueous with on-off-on mode. The fluorescence quenching mainly involves three procedures including the adsorption of Fe3+by hydrogel, integration of Fe3+with N, P-CQDs and the transportation of conjugate electrons in N, P-CQDs to the vacant orbits of Fe3+and the adsorption process follows a pseudo-second-order kinetic model confirmed in the Freundlich isotherm model. In conclusion, this work provides a novel route for synchronously removing and detecting the metal ions in aqueous by integrating N, P-CQDs with hydrogel with better recyclability.

19.
Eur J Radiol ; 166: 111000, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37531697

RESUMO

PURPOSE: To investigate the clinical value of the radiomics model of grayscale ultrasound (GUS) and contrast-enhanced ultrasound (CEUS) to diagnosis subpleural pulmonary tuberculosis and nonpulmonary tuberculosis based on GUS and CEUS images. METHODS: This study included 221 patients with 228 lesions diagnosed using the composite reference standard. The patients were randomly divided into training (n = 183) and test (n = 45) cohorts in an 8:2 ratio. The regions of interest of the GUS and CEUS images were manually segmented to extract the radiomic features. The GUS, CEUS and GUS+CEUS radiomics models were constructed via the multistep selection of highly correlated features. Receiver operating characteristic curves of the different models were plotted, and the area under the curve (AUC), accuracy, sensitivity, specificity, positive predictive value and negative predictive value (NPV) of the different models were compared. RESULTS: Following Least Absolute Shrinkage and Selection Operator dimension reduction we selected 4, 9, and 11 features to construct the GUS, CEUS, and GUS+CEUS radiomics models, respectively. The AUC values of the three groups in the test cohort were 0.689, 0.748 and 0.779, respectively, and they did not differ significantly. In the test cohort, the GUS+CEUS radiomics model exhibited the highest AUC (0.779), accuracy (75.56%), and NPV (68.7%) of the three models. CONCLUSIONS: The GUS+CEUS radiomics model possesses good clinical value in diagnosing pulmonary tuberculosis.


Assuntos
Tuberculose Extrapulmonar , Tuberculose Pulmonar , Humanos , Área Sob a Curva , Estudos Retrospectivos , Curva ROC , Tuberculose Pulmonar/diagnóstico por imagem , Tuberculose Extrapulmonar/diagnóstico por imagem
20.
Opt Express ; 31(14): 22323-22342, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37475346

RESUMO

With the advent of the hypersonic era, diverse combat methods of hypersonic precision-guided weapons have been gradually developed. This study focuses on the precise design of a conformal infrared dome to accommodate different working conditions. To achieve this, an adaptive optimization technology for configuring conformal infrared domes is proposed, employing a multi-objective genetic algorithm. The technology enables the dome to dynamically balance its aerodynamic and imaging performance, taking into account the specific characteristics of each working condition. Moreover, it streamlines the design process of the conformal infrared domes. By optimizing the design with von Karman surfaces, we can overcome the limitations associated with the traditional quadric configuration. In order to evaluate its performance, a comparison was made with a conventional ellipsoid dome. The results indicate that, under the same working conditions, the air drag coefficient of the optimized infrared dome is reduced by 34.29% and that the peak signal-to-noise ratio of the distorted image from the infrared detection system is increased by 1.7%. We have demonstrated the effectiveness of the optimization method to balance aerodynamic performance and optical performance. Hopefully, our new method will improve the comprehensive performance of the infrared dome as well as the guidance capability of infrared detection technology.

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