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1.
Phys Rev E ; 110(3-2): 035107, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39425420

RESUMEN

Although the high-fidelity state-to-state (StS) model accurately describes high-temperature thermochemical nonequilibrium flows, its practical application is hindered by the prohibitively high computational cost. In this paper, we develop a reduced-order model that leverages the widely used two-temperature (2T) framework and a coarse-grained treatment of molecular vibrational states to achieve accuracy comparable to the StS model while ensuring computational efficiency. We observe that the multigroup coarse-grained model (CGM), lumping vibrational energy levels into several groups, yields results close to the StS model for the high-temperature postshock oxygen flows, even using only two groups. However, the one-group CGM (CGM-1G), equivalent to the 2T model but using the StS kinetics, fails to approximate the StS results. Analysis of microscopic group properties reveals that the failure of the CGM-1G stems from the inability to capture the non-Boltzmann effects of mid-to-high vibrational levels, overestimating apparent dissociation rates and vibrational energy loss in the dissociation-dominated region. We then propose an analytical distribution function of vibrational groups by incorporating Treanor-like terms and an additional linear term (addressing the dissociation depletion of high-lying levels). Building upon this algebraic group distribution function and reconstructing vibrational levels within each group using the vibrational temperature, we develop a new 2T model called CG2T, which demonstrates accuracy much closer (than the CGM-1G) to the StS results for the postshock oxygen flows with varying degrees of thermochemical nonequilibrium. Moreover, a fullyconnected neural network is pretrained to substitute the module for the mass and vibrational energy source terms to enhance computational efficiency, achieving about 30-fold speedup in the CG2T model without sacrificing accuracy.

2.
Nanomaterials (Basel) ; 14(19)2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39404295

RESUMEN

Spherical quantum wells (SQWs) have proven to be excellent materials for suppressing Auger recombination due to their expanded confinement volume. However, research on the factors and mechanisms of their high-intensity optical properties, such as multiexciton properties and third-order optical nonlinearities, remains incomplete, limiting further optimization of these properties. Here, a series of CdS/CdSe (xML)/CdS SQWs with varying CdSe layer thicknesses were prepared. The modulation effects of CdSe shell variations on the PL properties, defect distribution, biexciton binding energy, and third-order optical nonlinearities of the SQWs were investigated, and their impact on the material's multiexciton properties was further analyzed. Results showed that the typical CdS/CdSe(3ML)/CdS sample exhibited a large volume-normalized two-photon absorption cross-section (18.17 × 102 GM/nm3) and favorable biexciton characteristics. Optical amplification was observed at 12.4 µJ/cm2 and 1.02 mJ/cm2 under one-photon (400 nm) and two-photon (800 nm) excitation, respectively. Furthermore, different amplified spontaneous emission spectra were observed for the first time under one/two-photon excitation. This phenomenon was attributed to thermal effects overcoming the biexciton binding energy. This study provides valuable insights for further optimizing multiexciton gain characteristics in SQWs and developing optical gain applications.

3.
Sci Rep ; 14(1): 22101, 2024 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-39333319

RESUMEN

Stereotactic radiation therapy (SBRT) has emerged as a promising treatment modality for locally advanced pancreatic cancer. The aim of this study is to assess the dosimetric efficacy of online adaptive radiotherapy (ART) in comparison to image-guided radiation therapy (IGRT) for pancreatic cancer. We conducted a retrospective analysis involving 8 patients diagnosed with locally advanced pancreatic cancer. The gross tumor volume (GTV) delineates the visible extent of the tumor on imaging, while the planning tumor volume (PTV) was generated by expanding 5 mm from the GTV and ensuring a 3 mm distance from the small intestine, duodenum, and stomach simultaneously. Treatment planning was executed using the United Imaging Healthcare Treatment Planning System workstation. The control group underwent evaluation based on daily validated fan-beam CT (FBCT) scans, assessing both the dose delivered to actual organs at risk (OARs) and the target volume. Radiotherapy plans were developed utilizing simulation CT, and conventional radiotherapy with daily image-guided radiation therapy (IGRT) was administered using FBCT-Linac. Conversely, patients in the study group received daily validated FBCT-guided adaptive radiotherapy plans, with a focus on mean dose assessment of both the target volume and OARs. Subsequently, we compared the average outcomes of each treatment fraction between IGRT and online adaptive radiotherapy (ART). Comparison between ART and IGRT treatment plans revealed significant differences in various dosimetric parameters: For PTV: V98%: ART (96.28%) vs IGRT (89.73%), p = 0.000, V95%: ART (96.28%) vs IGRT (89.73%), p = 0.031, V90%: ART (98.58%) vs IGRT (93.65%), p = 0.000, Dmean: ART (4912.91) vs IGRT (4804.11), p = 0.000. For GTV: V100%: ART (97.96%) vs IGRT (94.85%), p = 0.314, V98%: ART (100.00%) vs IGRT (96.83%), p = 0.000, V90%: ART (100.00%) vs IGRT (97.75%), p = 0.000, Dmean: ART (4972.17) vs IGRT (4907.23), p = 0.000. For the duodenum: D0.5cc: ART (2883.92) vs IGRT (3359.35), p = 0.000, D1cc: ART (2726.32) vs IGRT (3128.66), p = 0.001, D5cc: ART (2051.96) vs IGRT (2273.93), p = 0.015, D10cc: ART (1650.73) vs IGRT (1731.74), p = 0.211. For the small bowel: D0.5cc: ART (3022.3) vs IGRT (3142.64), p = 0.037. D5cc: ART (2151.09) vs IGRT (2389.15), p = 0.043, D10cc: ART (1775.20) vs IGRT (1942.00), p = 0.079. For the stomach: D0.5cc: ART (3353.92) vs IGRT (4117.85), p = 0.000, D5cc: ART (2860.20) vs IGRT (3235.41), p = 0.000, D10cc: ART (2553.72) vs IGRT (2836.73), p = 0.000. For the Dmean of the left kidney and right kidney: Left kidney: ART (248.28) vs IGRT (239.65), p = 0.100. Right kidney: ART (314.55) vs IGRT (307.17), p = 0.345. These results suggest significant improvements in PTV coverage and sparing of OARs with ART compared to IGRT, indicating the potential of ART in optimizing treatment outcomes for pancreatic cancer patients. Compared to conventional IGRT-guided SBRT programs, ART-based SBRT for pancreatic cancer not only enhances the dose distribution to the target volume but also mitigates the radiation exposure to critical organs-at-risk (OARs) such as the duodenum, small intestine, and stomach. This approach may offer a more favorable safety profile while concurrently enhancing treatment efficacy.


Asunto(s)
Neoplasias Pancreáticas , Radiocirugia , Planificación de la Radioterapia Asistida por Computador , Radioterapia Guiada por Imagen , Humanos , Neoplasias Pancreáticas/radioterapia , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/cirugía , Radiocirugia/métodos , Masculino , Femenino , Planificación de la Radioterapia Asistida por Computador/métodos , Estudios Retrospectivos , Anciano , Persona de Mediana Edad , Radioterapia Guiada por Imagen/métodos , Dosificación Radioterapéutica , Órganos en Riesgo/efectos de la radiación , Tomografía Computarizada por Rayos X
4.
Heliyon ; 10(17): e37590, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39309268

RESUMEN

Background: The unpleasant taste of polyethylene glycol (PEG) has been a hindrance to patients undergoing colonoscopy. Aim: This study aims to determine whether the addition of a vitamin drink (Mizone) to the 4L split-dose PEG regimen would be effective in improving the solution's palatability, and reducing patient discomfort during bowel preparation. Methods: The present prospective, single endoscopist-blinded, randomized controlled study randomly assigned patients into two groups: PEG + Mizone group (3.6 L of PEG solution plus 0.4 L of Mizone) and PEG group (4 L of PEG solution). Palatability was assessed using a Likert scale of 1-5. The adverse events, amount of unconsumed solution, and willingness to repeat the same process were recorded through a questionnaire. The present study was registered in the Chinese Clinical Trial Registry (ChiCTR2000034484). Results: A total of 132 patients were included. The demographic characteristics of these patients were comparable between the two groups. The palatability score (mean ± standard deviation [SD]) was higher in the PEG + Mizone group, when compared to the control group (4.00 ± 0.859 vs. 2.95 ± 0.999, p < 0.001). Furthermore, the incidence of nausea was lower in the PEG + Mizone group (9.1 % vs. 28.8 %, p = 0.004), while the other adverse events were similar between the two groups. The percentage of the completely consumed pre-prepared solution was significantly greater in the PEG + Mizone group (95.5 % vs. 78.8 %, p = 0.004). Furthermore, the willingness to repeat the same process was higher in the PEG + Mizone group (83.3 % vs. 42.4 %, p < 0.001). However, the consumption of either of these preparations did not significantly affect the electrolyte and blood glucose levels, and renal function. Conclusion: Compared to the conventional 4L PEG bowel preparation, the use of a vitamin drink (Mizone) as an adjuvant can improve the palatability, reduce adverse events, and increase the patient's willingness to undergo bowel preparation with the same regimen.

5.
Photodiagnosis Photodyn Ther ; 49: 104336, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39305942

RESUMEN

Biomarker testing plays a crucial role in the early detection of liver cancer. Herein, we developed a dual-signal amplification approach utilizing magnetic aggregation and a recognition competition strategy for the simultaneous detection of alpha-fetoprotein (AFP) and manganese superoxide dismutase (MnSOD) in serum. 4-MBA@AuNPs@H1 and DTNB@AuNPs@H2 were synthesized by functionalizing Raman signaling molecules and aptamer complementary chains onto the surface of gold nanoparticles (AuNPs). The detection complex Raman signal molecule@AuNPs@H-Fe3O4@cDNA was assembled by conjugating 4-MBA@AuNPs@H1 and DTNB@AuNPs@H2 with two nucleic acid aptamers (cDNA1 and cDNA2) modified with Fe3O4 through partial base complementary pairing. The target protein exhibited specific binding with the aptamer, leading to the competitive displacement of 4-MBA@AuNPs@H1 and DTNB@AuNPs@H2 from the Fe3O4 array surface, consequently resulting in a reduction of the Surface-Enhanced Raman Spectroscopy (SERS) signal. Through this approach, the limit of detection (LOD) for AFP and MnSOD in serum was achieved at remarkably low levels of 5.89 pg/mL and 6.23 pg/mL, respectively, with a reaction incubation period of only 5 min. Finally, the platform was utilized for the quantification of AFP and MnSOD in the serum of a nude mouse hepatocellular carcinoma model. The results obtained through SERS were consistent with those from enzyme-linked immunosorbent assay (ELISA), validating its accuracy. This methodology presents a novel approach for the swift and concurrent detection of proteins, holding significant clinical promise for the early diagnosis of hepatocellular carcinoma.


Asunto(s)
Oro , Límite de Detección , Neoplasias Hepáticas , Nanopartículas del Metal , Espectrometría Raman , Superóxido Dismutasa , alfa-Fetoproteínas , Espectrometría Raman/métodos , Neoplasias Hepáticas/sangre , Oro/química , alfa-Fetoproteínas/análisis , Nanopartículas del Metal/química , Animales , Ratones , Superóxido Dismutasa/sangre , Humanos , Biomarcadores de Tumor/sangre , Aptámeros de Nucleótidos
6.
Polymers (Basel) ; 16(15)2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-39125146

RESUMEN

The comprehensive performance of rubber products could be significantly improved by the addition of functional fillers. To improve research efficiency and decrease the experimental cost, the mechanical and thermal properties of carbon-fiber-reinforced rubber were investigated using finite element simulations and theoretical modeling. The simplified micromechanical model was constructed through the repeatable unit cell with periodic boundary conditions, and the corresponding theoretical models were built based on the rule of mixture (ROM), which can be treated as the mutual verification. The simulation results suggest that, in addition to the fiber volume fraction Vfc increasing from 10% to 70%, the longitudinal Young's modulus, transversal Young's modulus, in-plane shear modulus, longitudinal thermal expansion coefficient, and transversal thermal expansion coefficient changed from 2.31 × 1010 Pa to 16.09 × 1010 Pa, from 0.54 × 107 Pa to 2.59 × 107 Pa, from 1.66 × 106 Pa to 10.11 × 106 Pa, from -4.98 × 10-7 K-1 to -5.89 × 10-7 K-1, and from 5.72 × 10-4 K-1 to 1.66 × 10-4 K-1, respectively. The mechanism by which Vfc influences the properties of carbon-fiber-reinforced rubber was revealed through the distribution of Von Mises stress. This research will contribute to improving the performance of carbon-fiber-reinforced rubber and promote its application.

7.
BMC Endocr Disord ; 24(1): 152, 2024 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-39138447

RESUMEN

BACKGROUND: Previous studies examined the association of Helicobacter pylori infection (H. pylori) with complications of diabetes, but the results have been inconsistent. The aim of this study of patients with type-2 diabetes (T2D) was to determine the association of H. pylori infection with the major complications of diabetes. METHODS: This single-center retrospective study examined patients with T2D who received H. pylori testing between January 2016 and December 2021. Logistic regression analyses were used to evaluate the association of H. pylori infection with four major complications of diabetes. RESULTS: We examined 960 patients with T2D, and 481 of them (50.1%) were positive for H. pylori. H. pylori infection was significantly associated with diabetic nephropathy (odds ratio [OR] = 1.462; 95% confidence interval [CI]: 1.006,2.126; P = 0.046). In addition, the co-occurrence of H. pylori positivity with hypertension (OR = 4.451; 95% CI: 2.351,8.427; P < 0.001), with glycated hemoglobin A1c (HbA1c) of at least 8% (OR = 2.925; 95% CI: 1.544,5.541; P = 0.001), and with diabetes duration of at least 9 years (OR = 3.305; 95% CI:1.823,5.993; P < 0.001) further increased the risk of diabetic nephropathy. There was no evidence of an association of H. pylori infection with retinopathy, neuropathy, or peripheral vascular disease. CONCLUSIONS: Our study of T2D patients indicated that those with H. pylori infections had an increased risk of nephropathy, and this risk was greater in patients who also had hypertension, an HbA1c level of 8% or more, and diabetes duration of 9 years or more.


Asunto(s)
Diabetes Mellitus Tipo 2 , Nefropatías Diabéticas , Infecciones por Helicobacter , Helicobacter pylori , Humanos , Infecciones por Helicobacter/complicaciones , Estudios Retrospectivos , Masculino , Femenino , Persona de Mediana Edad , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/epidemiología , Helicobacter pylori/aislamiento & purificación , Nefropatías Diabéticas/epidemiología , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/complicaciones , Anciano , Complicaciones de la Diabetes/microbiología , Complicaciones de la Diabetes/epidemiología , Hemoglobina Glucada/análisis , Hemoglobina Glucada/metabolismo , Estudios de Seguimiento , Pronóstico , Adulto
8.
Biomed Pharmacother ; 178: 117221, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39111078

RESUMEN

Combining two or more chemicals in chemotherapy is rapidly increasing because of its higher efficacy, lower toxicity, lower dosages, and lower drug resistance. Here, we identified a novel combination of luteolin (LUT) and curcumin (CUR), two bioactive compounds from foods, synergistically suppressed triple-negative breast cancer (TNBC) cell proliferation (LUT 30 µM + CUR 20 µM), colony formation (LUT 1 µM + CUR 2 µM), and tumor growth in xenograft mice (LUT 10 mg/kg body weight/day + CUR 20 mg/kg body weight/day, i.p. injection every other day, 5 weeks), while the individual chemical alone did not show these inhibitory effects significantly at the selected concentrations/dosages. Our total RNA transcriptome analysis in xenograft tumors revealed that combining LUT and CUR synergistically activated type I interferon (IFN) signaling and suppressed transforming growth factor-beta (TGF-ß) signaling pathways, which was further confirmed by the expression/activity of several proteins of the pathways in tumors. In addition, this combination of LUT and CUR also synergistically decreased oncoprotein levels of c-Myc and Notch1, the critical molecules required to maintain stem cell properties, tumor clonal evolution, and drug resistance. These results suggest that the combination of LUT and CUR synergistically inhibits TNBC by suppressing multiple cellular mechanisms, such as proliferation, colony formation, and transformation, as well as tumor migration, invasion, and metastasis, via regulating IFN and TGF-ß signaling pathways. Therefore, combining LUT and CUR may be an effective therapeutic agent to treat highly aggressive, drug-resistant TNBC patients after clinical trials.


Asunto(s)
Curcumina , Luteolina , Transducción de Señal , Neoplasias de la Mama Triple Negativas , Animales , Femenino , Humanos , Ratones , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Curcumina/farmacología , Sinergismo Farmacológico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Luteolina/farmacología , Ratones Endogámicos BALB C , Ratones Desnudos , Transducción de Señal/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
9.
Adv Sci (Weinh) ; 11(38): e2406329, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39120492

RESUMEN

CO2 reduction photocatalysts are favorable for obtaining renewable energy. Enriched active sites and effective photogenerated-carriers separation are keys for improving CO2 photo-reduction. A thulium (Tm) single atom tailoring strategy introducing carbon vacancies in porous tubular graphitic carbon nitride (g-C3N4) surpassing the ever-reported g-C3N4 based photocatalysts, with 199.47 µmol g-1 h-1 CO yield, 96.8% CO selectivity, 0.84% apparent quantum efficiency and excellent photocatalytic stability, is implemented in this work. Results revealed that in-plane Tm sites and interlayer-bridged Tm-N charge transfer channels significantly enhanced the aggregation/transfer of photogenerated electrons thus promoting CO2 adsorption/activation and contributing to *COOH intermediates formation. Meanwhile, Tm atoms and carbon vacancies both benefit for rich active sites and enhanced photogenerated-charge separation, thus optimizing reaction pathway and leading to excellent CO2 photo-reduction. This work not only provides guidelines for CO2 photo-reduction catalysts design but also offers mechanistic insights into single-atom based photocatalysts for solar fuel production.

10.
J Am Chem Soc ; 146(29): 20312-20322, 2024 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-38980945

RESUMEN

Organic photovoltaic (OPV) devices attain high performance with nonfullerene acceptors by utilizing the synergistic dual channels of charge generation that originate from excitations in both the donor and acceptor materials. However, the specific intermediate states that facilitate both channels are subject to debate. To address this issue, we employ time-resolved terahertz spectroscopy with improved sensitivity (ΔE/E < 10-6), enabling direct probing of charge generation dynamics in a prototypical PM6:Y6 bulk heterojunction system under one-sun-equivalent excitation density. Charge generation arising from donor excitations is characterized with a rise time of ∼9 ps, while that from acceptor excitations shows a rise time of ∼18 ps. Temperature-dependent measurements further reveal notably distinct activation energies for these two charge generation pathways. Additionally, the two channels of charge generation can be substantially manipulated by altering the ratio of bulk to interfaces. These findings strongly suggest the presence of two distinct intermediate states: interfacial and intramoiety excitations. These states are crucial in mediating the transfer of electrons and holes, driving charge generation within OPV devices.

11.
Brachytherapy ; 23(5): 580-589, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38960768

RESUMEN

BACKGROUND AND PURPOSE: 3D-printed templates are used in intracavitary/interstitial brachytherapy (3DP-IC/IS) for locally advanced cervical cancer (LACC). We applied failure mode and effects analysis (FMEA) twice in one year to improve 3DP-IC/IS safety. MATERIALS AND METHODS: A risk assessment group was established. We created a process map for 3DP-IC/IS procedures, identifying potential failure modes (FMs) and evaluating occurrence (O), detectability (D), severity (S), and risk priority number (RPN = O*D*S). High RPN values identified high-risk FMs, and quality control (QC) methods were determined by root cause analysis. A second FMEA was performed a year later. RESULTS: The 3DP-IC/IS process included 10 main steps, 48 subprocesses, and 54 FMs. Initial RPN values ranged from 4.50 to 171.00 (median 50.50; average 52.18). Ten high-risk FMs were identified: (1) unreasonable needle track design (171.00/85.50), (2) noncoplanar needle label identification failure (126.00/64.00), (3) template model reconstruction failure (121.50/62.50), (4) improper gauze filling (112.00/60.25), (5) poor needle position (112.00/52.50). QC interventions lowered all high-risk RPN values during the second assessment. CONCLUSIONS: A feasible 3DP-IC/IS process was proposed. Staff training, automatic needle path planning, insertion guidance diagrams, template checking, system commissioning, and template design improvements effectively enhanced process safety.


Asunto(s)
Braquiterapia , Impresión Tridimensional , Neoplasias del Cuello Uterino , Humanos , Braquiterapia/instrumentación , Braquiterapia/métodos , Neoplasias del Cuello Uterino/radioterapia , Femenino , Análisis de Modo y Efecto de Fallas en la Atención de la Salud , Medición de Riesgo
12.
Molecules ; 29(13)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-38999073

RESUMEN

The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway is pivotal in immunotherapy. Several agonists and inhibitors of the cGAS-STING pathway have been developed and evaluated for the treatment of various diseases. The agonists aim to activate STING, with cyclic dinucleotides (CDNs) being the most common, while the inhibitors aim to block the enzymatic activity or DNA binding ability of cGAS. Meanwhile, non-CDN compounds and cGAS agonists are also gaining attention. The omnipresence of the cGAS-STING pathway in vivo indicates that its overactivation could lead to undesired inflammatory responses and autoimmune diseases, which underscores the necessity of developing both agonists and inhibitors of the cGAS-STING pathway. This review describes the molecular traits and roles of the cGAS-STING pathway and summarizes the development of cGAS-STING agonists and inhibitors. The information is supposed to be conducive to the design of novel drugs for targeting the cGAS-STING pathway.


Asunto(s)
Proteínas de la Membrana , Nucleotidiltransferasas , Transducción de Señal , Humanos , Nucleotidiltransferasas/metabolismo , Nucleotidiltransferasas/antagonistas & inhibidores , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/antagonistas & inhibidores , Proteínas de la Membrana/agonistas , Transducción de Señal/efectos de los fármacos , Animales , Enfermedades Autoinmunes/tratamiento farmacológico , Enfermedades Autoinmunes/metabolismo
13.
Heliyon ; 10(11): e31776, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38845904

RESUMEN

Safety-critical systems, such as the railway signal system, are subject to potentially high costs from failures, including loss of life and property damage. The use of new technology, including communication-based train control (CBTC) systems with software and computers, has changed the types of accidents that occur. Software-related issues and dysfunctional interactions between system components controlled by the software are increasingly the cause of incidents. Developing a "safe" safety-critical system requires accurate and complete safety requirements, which are the foundation of system development. Traditional hazard analysis techniques are insufficient for identifying the causes of accidents in modern railway signaling systems. Systems-Theoretic Process Analysis (STPA) is a powerful new hazard analysis method designed to address these limitations. Building upon this foundation, a hierarchical approach to safety requirement development has been further developed. This approach combines STPA analysis with a hierarchical modeling approach to establish traceability links from safety requirements to specific architectures, refine and allocate system-level safety requirements to relevant subsystems, and abstract safety requirements at higher hierarchical levels to enable easy changes to lower-level implementations. This paper employs the aforementioned methodology within the context of the CBTC system, thereby enhancing risk management and hazard analysis, enabling early insights, and facilitating the generation of safety requirements of CBTC System.

14.
Materials (Basel) ; 17(11)2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38894034

RESUMEN

Although quartz powder is a common concrete filling material, the importance and originality of this study lies in the development of a hydration model for quartz powder-cement binary mixtures and the adoption of this model to predict the development of concrete material properties. The purpose of this study is to use this model to promote the material design of environmentally friendly concrete and to elucidate the relationships in the development of the various properties of quartz powder concrete. The method used in this study was as follows: The parameters of the hydration model were obtained through seven days of hydration heat experiments. The hydration heat up to 28 days was also calculated, and the various properties of the concrete were predicted from the heat of hydration. The main findings of this study were as follows: (1) The ultimate hydration heat released per gram of cement for the different quartz powder substitution rates and quartz powder particle fineness was the same, at 390.145 J/g cement, as was the shape index of the hydration model at -1.003. (2) Moreover, through the model calculations, we found that, at the twenty-eighth day of the curing period for the quartz powder specimens with different quartz powder substitution amounts and different fineness, the reaction level of the cement was similar, at 0.963, as were the values of the cumulative heat of hydration, with both at 375.5 J/g cement. (3) The model showed that, in the late stage (28 days) of hydration for quartz powders of different fineness and when the substitution amount was the same, the cumulative heat of hydration over 28 days was similar. (4) The properties of concrete were evaluated using the calculated hydration heat. Overall, the predictive performance of the power and linear functions was similar, with no significant differences being found.

15.
Mikrochim Acta ; 191(7): 415, 2024 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907752

RESUMEN

A novel approach is proposed leveraging surface-enhanced Raman spectroscopy (SERS) combined with machine learning (ML) techniques, principal component analysis (PCA)-centroid displacement-based nearest neighbor (CDNN). This label-free approach can identify slight abnormalities between SERS spectra of gastric lesions at different stages, offering a promising avenue for detection and prevention of precancerous lesion of gastric cancer (PLGC). The agaric-shaped nanoarray substrate was prepared using gas-liquid interface self-assembly and reactive ion etching (RIE) technology to measure SERS spectra of serum from mice model with gastric lesions at different stages, and then a SERS spectral recognition model was trained and constructed using the PCA-CDNN algorithm. The results showed that the agaric-shaped nanoarray substrate has good uniformity, stability, cleanliness, and SERS enhancement effect. The trained PCA-CDNN model not only found the most important features of PLGC, but also achieved satisfactory classification results with accuracy, area under curve (AUC), sensitivity, and specificity up to 100%. This demonstrated the enormous potential of this analysis platform in the diagnosis of PLGC.


Asunto(s)
Aprendizaje Automático , Lesiones Precancerosas , Espectrometría Raman , Neoplasias Gástricas , Neoplasias Gástricas/diagnóstico , Espectrometría Raman/métodos , Animales , Lesiones Precancerosas/diagnóstico , Lesiones Precancerosas/sangre , Ratones , Análisis de Componente Principal
16.
Phys Med ; 123: 103393, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38852363

RESUMEN

BACKGROUND AND PURPOSE: One of the current roadblocks to the widespread use of Total Marrow Irradiation (TMI) and Total Marrow and Lymphoid Irradiation (TMLI) is the challenging difficulties in tumor target contouring workflow. This study aims to develop a hybrid neural network model that promotes accurate, automatic, and rapid segmentation of multi-class clinical target volumes. MATERIALS AND METHODS: Patients who underwent TMI and TMLI from January 2018 to May 2022 were included. Two independent oncologists manually contoured eight target volumes for patients on CT images. A novel Dual-Encoder Alignment Network (DEA-Net) was developed and trained using 46 patients from one internal institution and independently evaluated on a total of 39 internal and external patients. Performance was evaluated on accuracy metrics and delineation time. RESULTS: The DEA-Net achieved a mean dice similarity coefficient of 90.1 % ± 1.8 % for internal testing dataset (23 patients) and 91.1 % ± 2.5 % for external testing dataset (16 patients). The 95 % Hausdorff distance and average symmetric surface distance were 2.04 ± 0.62 mm and 0.57 ± 0.11 mm for internal testing dataset, and 2.17 ± 0.68 mm, and 0.57 ± 0.20 mm for external testing dataset, respectively, outperforming most of existing state-of-the-art methods. In addition, the automatic segmentation workflow reduced delineation time by 98 % compared to the conventional manual contouring process (mean 173 ± 29 s vs. 12168 ± 1690 s; P < 0.001). Ablation study validate the effectiveness of hybrid structures. CONCLUSION: The proposed deep learning framework achieved comparable or superior target volume delineation accuracy, significantly accelerating the radiotherapy planning process.


Asunto(s)
Médula Ósea , Aprendizaje Profundo , Planificación de la Radioterapia Asistida por Computador , Humanos , Médula Ósea/efectos de la radiación , Médula Ósea/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Irradiación Linfática/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Tomografía Computarizada por Rayos X , Masculino , Femenino
17.
J Phys Chem Lett ; 15(26): 6763-6770, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38912978

RESUMEN

Ion migration is significantly enhanced in lead-halide perovskites with a soft crystal lattice, which can promote the formation of a heterogeneous interface between two such materials with different halide-anion compositions. Here we have deposited a single CsPbI3 nanocrystal (NC) on top of an individual CsPbBr3 microplate to create a mixed-halide CsPbBrxI3-x (0 < x < 3) NC by means of the anion exchange process. The formation of a CsPbBrxI3-x/CsPbBr3 heterostructure is confirmed by the much-enlarged geometric volume of the CsPbBrxI3-x NC as compared to the original CsPbI3 one, as well as by its capability of receiving photogenerated excitons from the CsPbBr3 microplate with a larger bandgap energy. The quantum nature of this heterostructure is reflected from single-photon emission of the composing CsPbBrxI3-x NC, which can also be bulk-like during phase segregation to demonstrate a red shift in the photoluminescence peak that is opposite to the common trend observed in smaller-sized mixed-halide NCs.

18.
J Clin Oncol ; 42(25): 2966-2977, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38843483

RESUMEN

PURPOSE: Artificial intelligence can reduce the time used by physicians on radiological assessments. For 18F-fluorodeoxyglucose-avid lymphomas, obtaining complete metabolic response (CMR) by end of treatment is prognostic. METHODS: Here, we present a deep learning-based algorithm for fully automated treatment response assessments according to the Lugano 2014 classification. The proposed four-stage method, trained on a multicountry clinical trial (ClinicalTrials.gov identifier: NCT01287741) and tested in three independent multicenter and multicountry test sets on different non-Hodgkin lymphoma subtypes and different lines of treatment (ClinicalTrials.gov identifiers NCT02257567, NCT02500407; 20% holdout in ClinicalTrials.gov identifier NCT01287741), outputs the detected lesions at baseline and follow-up to enable focused radiologist review. RESULTS: The method's response assessment achieved high agreement with the adjudicated radiologic responses (eg, agreement for overall response assessment of 93%, 87%, and 85% in ClinicalTrials.gov identifiers NCT01287741, NCT02500407, and NCT02257567, respectively) similar to inter-radiologist agreement and was strongly prognostic of outcomes with a trend toward higher accuracy for death risk than adjudicated radiologic responses (hazard ratio for end of treatment by-model CMR of 0.123, 0.054, and 0.205 in ClinicalTrials.gov identifiers NCT01287741, NCT02500407, and NCT02257567, compared with, respectively, 0.226, 0.292, and 0.272 for CMR by the adjudicated responses). Furthermore, a radiologist review of the algorithm's assessments was conducted. The radiologist median review time was 1.38 minutes/assessment, and no statistically significant differences were observed in the level of agreement of the radiologist with the model's response compared with the level of agreement of the radiologist with the adjudicated responses. CONCLUSION: These results suggest that the proposed method can be incorporated into radiologic response assessment workflows in cancer imaging for significant time savings and with performance similar to trained medical experts.


Asunto(s)
Aprendizaje Profundo , Fluorodesoxiglucosa F18 , Linfoma no Hodgkin , Humanos , Linfoma no Hodgkin/diagnóstico por imagen , Linfoma no Hodgkin/metabolismo , Tomografía de Emisión de Positrones/métodos , Radiofármacos , Femenino , Masculino
19.
Int J Nanomedicine ; 19: 4465-4493, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38779103

RESUMEN

Background: Liver cancer remains to be one of the leading causes of cancer worldwide. The treatment options face several challenges and nanomaterials have proven to improve the bioavailability of several drug candidates and their applications in nanomedicine. Specifically, chitosan nanoparticles (CNPs) are extremely biodegradable, pose enhanced biocompatibility and are considered safe for use in medicine. Methods: CNPs were synthesized by ionic gelation, loaded with rutin (rCNPs) and characterized by ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The rCNPs were tested for their cytotoxic effects on human hepatoma Hep3B cells, and experiments were conducted to determine the mechanism of such effects. Further, the biocompatibility of the rCNPs was tested on L929 fibroblasts, and their hemocompatibility was determined. Results: Initially, UV-vis and FTIR analyses indicated the possible loading of rutin on rCNPs. Further, the rutin load was quantitatively measured using Ultra-Performance Liquid Chromatography (UPLC) and the concentration was 88 µg/mL for 0.22 micron filtered rCNPs. The drug loading capacity (LC%) of the rCNPs was observed to be 13.29 ± 0.68%, and encapsulation efficiency (EE%) was 19.55 ± 1.01%. The drug release was pH-responsive as 88.58% of the drug was released after 24 hrs at the lysosomal pH 5.5, whereas 91.44% of the drug was released at physiological pH 7.4 after 102 hrs. The cytotoxic effects were prominent in 0.22 micron filtered samples of 5 mg/mL rutin precursor. The particle size for the rCNPs at this concentration was 144.1 nm and the polydispersity index (PDI) was 0.244, which is deemed to be ideal for tumor targeting. A zeta potential (ζ-potential) value of 16.4 mV indicated rCNPs with good stability. The IC50 value for the cytotoxic effects of rCNPs on human hepatoma Hep3B cells was 9.7 ± 0.19 µg/mL of rutin load. In addition, the increased production of reactive oxygen species (ROS) and changes in mitochondrial membrane potential (MMP) were observed. Gene expression studies indicated that the mechanism for cytotoxic effects of rCNPs on Hep3B cells was due to the activation of Unc-51-like autophagy-activating kinase (ULK1) mediated autophagy and nuclear factor kappa B (NF-κB) signaling besides inhibiting the epithelial-mesenchymal Transition (EMT). In addition, the rCNPs were less toxic on NCTC clone 929 (L929) fibroblasts in comparison to the Hep3B cells and possessed excellent hemocompatibility (less than 2% of hemolysis). Conclusion: The synthesized rCNPs were pH-responsive and possessed the physicochemical properties suitable for tumor targeting. The particles were effectively cytotoxic on Hep3B cells in comparison to normal cells and possessed excellent hemocompatibility. The very low hemolytic profile of rCNPs indicates that the drug could be administered intravenously for cancer therapy.


Asunto(s)
Autofagia , Carcinoma Hepatocelular , Quitosano , Neoplasias Hepáticas , FN-kappa B , Nanopartículas , Rutina , Transducción de Señal , Rutina/farmacología , Rutina/química , Rutina/administración & dosificación , Rutina/farmacocinética , Quitosano/química , Quitosano/farmacología , Humanos , FN-kappa B/metabolismo , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/metabolismo , Nanopartículas/química , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Autofagia/efectos de los fármacos , Línea Celular Tumoral , Transducción de Señal/efectos de los fármacos , Transición Epitelial-Mesenquimal/efectos de los fármacos , Ratones , Animales , Portadores de Fármacos/química , Portadores de Fármacos/farmacología , Supervivencia Celular/efectos de los fármacos
20.
Nanoscale ; 16(18): 9136, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38661520

RESUMEN

Expression of concern for 'Gadolinium embedded iron oxide nanoclusters as T1-T2 dual-modal MRI-visible vectors for safe and efficient siRNA delivery' by Xiaoyong Wang et al., Nanoscale, 2013, 5, 8098-8104, https://doi.org/10.1039/C3NR02797J.


Asunto(s)
Gadolinio , Imagen por Resonancia Magnética , ARN Interferente Pequeño , ARN Interferente Pequeño/química , ARN Interferente Pequeño/metabolismo , Gadolinio/química , Humanos , Compuestos Férricos/química , Medios de Contraste/química , Nanopartículas Magnéticas de Óxido de Hierro/química , Animales
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