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1.
Sensors (Basel) ; 24(12)2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38931713

RESUMO

The rapid advancements in Artificial Intelligence of Things (AIoT) are pivotal for the healthcare sector, especially as the world approaches an aging society which will be reached by 2050. This paper presents an innovative AIoT-enabled data fusion system implemented at the CMUH Respiratory Intensive Care Unit (RICU) to address the high incidence of medical errors in ICUs, which are among the top three causes of mortality in healthcare facilities. ICU patients are particularly vulnerable to medical errors due to the complexity of their conditions and the critical nature of their care. We introduce a four-layer AIoT architecture designed to manage and deliver both real-time and non-real-time medical data within the CMUH-RICU. Our system demonstrates the capability to handle 22 TB of medical data annually with an average delay of 1.72 ms and a bandwidth of 65.66 Mbps. Additionally, we ensure the uninterrupted operation of the CMUH-RICU with a three-node streaming cluster (called Kafka), provided a failed node is repaired within 9 h, assuming a one-year node lifespan. A case study is presented where the AI application of acute respiratory distress syndrome (ARDS), leveraging our AIoT data fusion approach, significantly improved the medical diagnosis rate from 52.2% to 93.3% and reduced mortality from 56.5% to 39.5%. The results underscore the potential of AIoT in enhancing patient outcomes and operational efficiency in the ICU setting.


Assuntos
Inteligência Artificial , Unidades de Terapia Intensiva , Humanos , Síndrome do Desconforto Respiratório/terapia
2.
ACS Nano ; 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38919047

RESUMO

Atomic layer deposition (ALD) is an effective technique for depositing thin films with precise control of layer thickness and functional properties. In this work, Sb2Te3-Sb2Se3 nanostructures were synthesized using thermal ALD. A decrease in the Sb2Te3 layer thickness led to the emergence of distinct peaks from the Laue rings, indicative of a highly textured film structure with optimized crystallinity. Density functional theory simulations revealed that carrier redistribution occurs at the interface to establish charge equilibrium. By carefully optimizing the layer thicknesses, we achieved an obvious enhancement in the Seebeck coefficient, reaching a peak figure of merit (zT) value of 0.38 at room temperature. These investigations not only provide strong evidence for the potential of ALD manipulation to improve the electrical performance of metal chalcogenides but also offer valuable insights into achieving high performance in two-dimensional materials.

3.
Beijing Da Xue Xue Bao Yi Xue Ban ; 56(3): 471-478, 2024 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-38864133

RESUMO

OBJECTIVE: Telemedicine, as an information-based tool, is widely recognized as an effective solution for compensating for the imbalanced allocation of medical resources in China. This study specifi-cally aimed to analyze the impact of telemedicine functions on the operational efficiency of public hospitals, with a particular focus on their heterogeneous effects on hospitals of different levels. METHODS: A cross-sectional research design was used based on the 2022 Health Informatization Statistical Survey data, and 8 944 public hospitals were used as research objects to analyze the impact of telemedicine on hospital revenues and business capacity. Multivariate linear model, propensity score matching (PSM), and grouped regression methods were employed to evaluate the impact of telemedicine on hospital revenues, number of consultations, and the number of discharges. RESULTS: The descriptive results showed that telemedicine was available in 35.51% of public hospitals. The analysis also demonstrated that various factors, such as hospital level, academic category, area of the hospital, administrational level and number of beds all had a significant influence on the operation of the hospital. Moreover, the regression results showed that opening telemedicine could increase hospital revenues by 0.140 (P < 0.01), hospital consultations by 0.136 (P < 0.01), and the number of discharges by 0.316 (P < 0.01). After correcting for endogeneity using the propensity score matching, the results showed that the effect of opening telemedicine on hospital revenues, consultations, and the number of discharges was 0.191 (P < 0.01), 0.216 (P < 0.01), and 0.353 (P < 0.01), respectively. Further heterogeneity analysis was conducted to explore the differential effects of telemedicine on hospitals of different levels. Grouped regression showed that telemedicine had a positive impact on the income of secondary hospitals, with a coefficient of 0.088 (P < 0.05), and it had a more significant positive impact on hospital consultations in secondary hospitals, with a coefficient of 0.127 (P < 0.01). An even greater impact on the number of discharges in primary hospitals, with a coefficient of 1.203 (P < 0.01). Telemedicine, on the other hand, did not have a significant positive impact on the overall revenue and operational capacity of tertiary hospitals. CONCLUSION: Telemedicine had a significant promoting effect on hospital revenues, hospital consultations and the number of discharges, and this effect was differentiated between hospitals of different levels. Through the construction of telemedicine, primary hospitals were able to significantly improve their business capacity and revenue, which played a positive role in improving the operation of primary public hospitals.


Assuntos
Hospitais Públicos , Telemedicina , Hospitais Públicos/estatística & dados numéricos , China , Telemedicina/economia , Estudos Transversais , Humanos , Pontuação de Propensão
4.
Bioresour Technol ; 406: 130964, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38876279

RESUMO

Biomethane recovery from paper waste (PW) was achieved by mesophilic co-digestion with food waste. The feeding material containing 0%, 20%, 40% and 50% of PW in total solids (TS) were investigated in the long-term continuous operation. The results showed that the biogas production, pH, alkalinity and biodegradation of volatile solids (79.8 ± 3.6%) were stable for PW contents no more than 50%. The PW = 50% condition was considered the critical limit for the reasons of pump clogging, sufficient alkalinity (2.0 ± 0.3 g-CaCO3/L) and depletion of ammonia. Prokaryotic diversity indices decreased with the increased PW contents. Great shifts were observed in the prokaryotic communities before and after the PW contents reaches 50% as TS (18.4% as total weights). Biomethane recovery yields were deceasing from 445 to 350 NL-CH4/kg-fed-volatile-solids. The PW contents as 40% as TS (13.1% as total weights) obtained the optimal performance among all the feeding conditions.

5.
ACS Appl Mater Interfaces ; 16(23): 30462-30470, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38830131

RESUMO

Garnet-type Li6.75La3Zr1.75Ta0.25O12 (LLZTO) is a promising solid-state electrolyte (SSE) because of its fast ionic conduction and notable chemical/electrochemical stability toward the lithium (Li) metal. However, poor interface wettability and large interface resistance between LLZTO and Li anode greatly restrict its practical applications. In this work, we develop an in situ chemical conversion strategy to construct a highly conductive Li2S@C layer on the surface of LLZTO, enabling improved interfacial wettability between LLZTO and the Li anode. The Li/Li2S@C-LLZTO-Li2S@C/Li symmetric cell has a low interface impedance of 78.5 Ω cm2, much lower than the 970 Ω cm2 of a Li/LLZTO/Li cell. Moreover, the Li/Li2S@C-LLZTO-Li2S@C/Li cell exhibits a high critical current density of 1.4 mA cm-2 and an ultralong stability of 3000 h at 0.1 mA cm-2. When used in a LiFePO4 battery, the Li/Li2S@C-LLZTO/LiFePO4 battery exhibits a high initial discharge capacity of 150.8 mA h g-1 at 0.2 C without lithium storage capacity attenuation during 200 cycles. This work provides a novel and feasible strategy to address interface issues of SSEs and achieve lithium-dendrite-free solid-state batteries.

7.
Chem Commun (Camb) ; 60(43): 5622-5625, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38715529

RESUMO

We report that the use of a hydrogen-bonded pyrimidine-macrocycle complex can efficiently facilitate the threading of two bispyridinium ethylenes into four rings, as evidenced by X-ray crystallography of its precursor, offering a rare example of a doubly threaded [6]rotaxane in 91% yield. The unusual architecture is found to be stable with no dethreading despite the large ring size of the macrocycle with respect to the stopper.

8.
Nanotechnology ; 35(33)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38744256

RESUMO

Secondary battery as an efficient energy conversion device has been highly attractive for alleviating the energy crisis and environmental pollution. Hierarchical porous carbon (HPC) materials with multiple sizes pore channels are considered as promising materials for energy conversion and storage applications, due to their high specific surface area and excellent electrical conductivity. Although many reviews have reported on carbon materials for different fields, systematic summaries about HPC materials for lithium storage are still rare. In this review, we first summarize the main preparation methods of HPC materials, including hard template method, soft template method, and template-free method. The modification methods including porosity and morphology tuning, heteroatom doping, and multiphase composites are introduced systematically. Then, the recent advances in HPC materials on lithium storage are summarized. Finally, we outline the challenges and future perspectives for the application of HPC materials in lithium storage.

9.
Shock ; 61(6): 841-847, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691102

RESUMO

ABSTRACT: Objective: To investigate the protective effect and possible mechanisms of vitamin B 6 against renal injury in patients with sepsis. Methods: A total of 128 patients with sepsis who met the entry criteria in multiple centers were randomly divided into experimental (intravenous vitamin B 6 therapy) and control (intravenous 0.9% sodium chloride therapy) groups based on usual care. Clinical data, the inflammatory response indicators interleukin 6 (IL-6), interleukin 8 (IL-8), tumor necrosis factor (TNF-α), and endothelin-1 (ET-1), the oxidative stress response indicators superoxide dismutase, glutathione and malondialdehyde, and renal function (assessed by blood urea nitrogen, serum creatinine, and renal resistance index monitored by ultrasound) were compared between the two groups. Results: After 7 d of treatment, the IL-6, IL-8, TNF-α, and ET-1 levels in the experimental group were significantly lower than those in the control group, the oxidative stress response indicators were significantly improved in the experimental group and the blood urea nitrogen, serum creatinine, and renal resistance index values in the experimental group were significantly lower than those in the control group ( P < 0.05). There was no statistical difference between the two groups in the rate of renal replacement therapy and 28 d mortality ( P > 0.05). However, the intensive care unit length of stay and the total hospitalization expenses in the experimental group were significantly lower than those in the control group ( P < 0.05). Conclusion: The administration of vitamin B 6 in the treatment of patients with sepsis attenuates renal injury, and the mechanism may be related to pyridoxine decreasing the levels of inflammatory mediators and their regulation by redox stress.


Assuntos
Estresse Oxidativo , Sepse , Vitamina B 6 , Humanos , Sepse/tratamento farmacológico , Sepse/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estresse Oxidativo/efeitos dos fármacos , Vitamina B 6/uso terapêutico , Endotelina-1/sangue , Fator de Necrose Tumoral alfa/sangue , Interleucina-6/sangue , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/prevenção & controle , Interleucina-8/sangue , Superóxido Dismutase/sangue , Rim/efeitos dos fármacos , Rim/metabolismo , Nitrogênio da Ureia Sanguínea , Malondialdeído/sangue , Creatinina/sangue
10.
PLoS One ; 19(5): e0302311, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38814929

RESUMO

This study aimed to enhance sludge dewatering through sequential bioleaching, employing the filamentous fungus Mucor sp. ZG-3 and the iron-oxidizing bacterium Acidithiobacillus ferrooxidans LX5. The mechanism by which Mucor sp. ZG-3 alleviates sludge dissolved organic matter (DOM) inhibition of A. ferrooxidans LX5 was investigated, and the optimal addition of energy source for enhanced sludge dewaterability during sequential bioleaching was determined. Sludge dissolved organic carbon (DOC) decreased to 272 mg/L with a 65.2% reduction by Mucor sp. ZG-3 in 3 days, and the degraded fraction of sludge DOM was mainly low-molecular-weight DOM (L-DOM) which inhibited the oxidization of Fe2+ by A. ferrooxidans LX5. By degrading significant inhibitory low-molecular-weight organic acids, Mucor sp. ZG-3 alleviated DOM inhibition of A. ferrooxidans LX5. In the sequential bioleaching process, the optimal concentration of FeSO4·7H2O for A. ferrooxidans LX5 was 4 g/L, resulting in the minimum specific resistance to filtration (SRF) of 2.60×1011 m/kg, 40.0% lower than that in the conventional bioleaching process with 10 g/L energy source. Moreover, the sequential bioleaching process increased the sludge zeta potential (from -31.8 to -9.47 mV) and median particle size (d50) of the sludge particle (from 17.90 to 27.44 µm), contributing to enhanced sludge dewaterability. Inoculation of Mucor sp. ZG-3 during the bioleaching process reduced the demand for energy sources by A. ferrooxidans LX5 while improving sludge dewaterability performance.


Assuntos
Mucor , Esgotos , Mucor/metabolismo , Esgotos/microbiologia , Biodegradação Ambiental , Água/química , Água/metabolismo , Compostos Orgânicos/metabolismo
11.
Nat Commun ; 15(1): 4441, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38789409

RESUMO

Ideal hydrogel fibers with high toughness and environmental tolerance are indispensable for their long-term application in flexible electronics as actuating and sensing elements. However, current hydrogel fibers exhibit poor mechanical properties and environmental instability due to their intrinsically weak molecular (chain) interactions. Inspired by the multilevel adjustment of spider silk network structure by ions, bionic hydrogel fibers with elaborated ionic crosslinking and crystalline domains are constructed. Bionic hydrogel fibers show a toughness of 162.25 ± 21.99 megajoules per cubic meter, comparable to that of spider silks. The demonstrated bionic structural engineering strategy can be generalized to other polymers and inorganic salts for fabricating hydrogel fibers with broadly tunable mechanical properties. In addition, the introduction of inorganic salt/glycerol/water ternary solvent during constructing bionic structures endows hydrogel fibers with anti-freezing, water retention, and self-regeneration properties. This work provides ideas to fabricate hydrogel fibers with high mechanical properties and stability for flexible electronics.

12.
Small ; : e2402168, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38757427

RESUMO

A metal-free nanocarbon with an eggshell structure is synthesized from chitosan (CS) and natural spherical graphite (NSG) as a cathode electrocatalyst for clean zinc-air batteries and fuel cells. It is developed using CS-derived carbons as an eggshell, covering NSG cores. The synthesis involves the in situ growth of CS on NSG, followed by ammonia-assisted pyrolysis for carbonization. The resulting catalyst displays a curved structure and completely coated NSG, showing superior oxygen reduction reaction (ORR) performance. In 1 M NaOH, the ORR half-wave potential reached 0.93 V, surpassing the commercial Pt/C catalyst by 50 mV. Furthermore, a zinc-air battery featuring the catalyst achieves a peak power density of 167 mW cm-2 with excellent stability, outperforming the Pt/C. The improved performance of the eggshell carbons can be attributed to the distorted energy band of the active sites in the form of N-C moieties. More importantly, the curved thin eggshells induce built-in electric fields that can promote electron redistribution to generate atomic charge waves around the N-C moieties on the carbon shells. As a result, the high positively charged and stable C+ sites adjacent to N atoms optimize the adsorption strength of oxygen molecules, thereby facilitating performance.

13.
Ultramicroscopy ; 262: 113978, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38692141

RESUMO

In this work we instigated the fragmentation of Au microparticles supported on a thin amorphous carbon film by irradiating them with a gradually convergent electron beam inside the Transmission Electron Microscope. This phenomenon has been generically labeled as "electron beam-induced fragmentation" or EBIF and its physical origin remains contested. On the one hand, EBIF has been primarily characterized as a consequence of beam-induced heating. On the other, EBIF has been attributed to beam-induced charging eventually leading to Coulomb explosion. To test the feasibility of the charging framework for EBIF, we instigated the fragmentation of Au particles under two different experimental conditions. First, with the magnetic objective lens of the microscope operating at full capacity, i.e. background magnetic field B=2 T, and with the magnetic objective lens switched off (Lorenz mode), i.e. B=0 T. We observe that the presence or absence of the magnetic field noticeably affects the critical current density at which EBIF occurs. This strongly suggests that magnetic field effects play a crucial role in instigating EBIF on the microparticles. The dependence of the value of the critical current density on the absence or presence of an ambient magnetic field cannot be accounted for by the beam-induced heating model. Consequently, this work presents robust experimental evidence suggesting that Coulomb explosion driven by electrostatic charging is the root cause of EBIF.

14.
Neurotoxicology ; 102: 68-80, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38599288

RESUMO

Melamine-tainted products have been found in the market and raised issues about food safety. Recent studies done in rodents and humans demonstrated the toxicities of melamine, especially in causing kidney damage and bladder stone formation. However, very few studies assessed its behavior toxicity in organisms, including fish. Therefore, in this study, the researchers aim to determine whether sub-chronic exposure to melamine via oral and systematic administration could induce behavioral abnormality in zebrafish. After 14 days of systematic exposure to melamine at doses of 0.1 and 10 ppm levels, zebrafish were subjected to multiple behavioral assays. Results from both exposure routes showed that melamine indeed slightly increased fish locomotion and altered their exploratory behaviors in the novel tank assay. Furthermore, tightened shoaling formation was also displayed by the treated fish in the waterborne exposure group. However, melamine exposure did not cause any obvious alterations in fish behaviors during other behavioral tests. In addition, in comparison with previously published data on the behavior toxicities of several solvents in zebrafish, our phenomic analysis suggests the relatively low behavior toxicities of melamine via either systematic exposure or oral administration to zebrafish compared to those solvents. Nevertheless, our data indicate that the potential neurotoxicity of chronic low-dose melamine should not be ignored.


Assuntos
Comportamento Animal , Triazinas , Peixe-Zebra , Animais , Triazinas/toxicidade , Triazinas/administração & dosagem , Comportamento Animal/efeitos dos fármacos , Administração Oral , Locomoção/efeitos dos fármacos , Comportamento Exploratório/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino
15.
Chem Asian J ; 19(11): e202400163, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38606886

RESUMO

Pollution from harmful heavy metal ions such as Pb(II) and Cu(II) is causing serious environmental and health problems. In this study, Sodium and nitrogen co-doped porous carbon material (Na/NABc) was successfully prepared from seaweed, sodium hydroxide, and dicyandiamide. The experimental results showed that Na/NABc is an excellent adsorbent for the effective removal of Pb(II) and Cu(II) from water bodies. Specifically, 99.8% of Pb(II) and 64.6% Cu(II) (100 mg/L) were removed within 12 h using 10 mg Na/NABc(10%) at 25 °C. The adsorption of Pb(II) and Cu(II) in aqueous solution by Na/NABc(10%) was efficient and rapid in the first stage. The theoretical maximum removal capacities of Na/NABc for Pb(II) and Cu(II) were 959.6 and 299.1 mg/g, respectively. Pb(II) and Cu(II) ions were adsorbed quickly in the first 60 min, and the kinetics data were generally consistent with a pseudo-second-order model. Na/NABc(10%) had a large distribution coefficient for Pb(II) (8.38 L/mg) and Cu(II) (1.17 L/mg). The possible mechanisms were precipitation, Ion exchange, and surface complexation. The removal rate can reach about 70% after five cycles, and the release of sodium meets the standard. The results of this study demonstrate the potential applicability of Na/NABc(10%) for adsorption of heavy metals from aqueous solution.


Assuntos
Carvão Vegetal , Cobre , Chumbo , Nitrogênio , Alga Marinha , Sódio , Poluentes Químicos da Água , Cobre/química , Chumbo/química , Chumbo/isolamento & purificação , Alga Marinha/química , Carvão Vegetal/química , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Adsorção , Sódio/química , Nitrogênio/química , Purificação da Água/métodos , Cinética , Água/química
16.
Medicine (Baltimore) ; 103(17): e37858, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38669397

RESUMO

RATIONALE: Bian stone ironing and rubbing traditional Chinese medicine penetration method is based on the theory of regulating the middle and restoring balance. By using Bian stone to heat, ironing, and rubbing, pushing and rubbing in the epigastric area can regulate the spleen and stomach, restore the normal function of the middle jiao qi movement and the functions of the five organs. Bian stone hot ironing can harmonize stomach qi, nourish qi and assist yang, clear the internal organs and clear turbidity, regulate intestinal qi circulation, and promote qi stagnation. PATIENT CONCERNS: The VAS score for stomach pain is 6 points, and the SAS score is moderate anxiety, which seriously affects sleep and daily life. DIAGNOSES: epigastric pain, spleen, and stomach deficiency cold syndrome. INTERVENTIONS: Easy to digest diet, Western medicine provides famotidine acid inhibiting and protecting gastric mucosa, and mosapride promoting gastrointestinal peristalsis medication treatment; Traditional Chinese Medicine provides oral administration of Huangqi Jianzhong Tang and traditional Chinese medicine techniques such as Bianchi Ironing and Moxibustion for treatment. OUTCOMES: The patient's symptoms of stomach pain have significantly improved, with a decrease in the epigastric pain score to 0, improved anxiety, reduced fatigue, improved sleep, improved epigastric fullness, unobstructed bowel movements, and improved quality of life. The patient is very satisfied. LESSONS: The method of using Bian stone ironing and rubbing traditional Chinese medicine to treat stomach pain caused by the spleen and stomach deficiency cold can alleviate the symptoms of stomach pain in patients, and the improvement of symptoms shows a gradual increase, with significant effects. At the same time, it significantly improves patient anxiety and fatigue symptoms and can increase the sample size in future work to further clarify its clinical effects.


Assuntos
Dor Abdominal , Medicina Tradicional Chinesa , Feminino , Humanos , Dor Abdominal/etiologia , Dor Abdominal/terapia , Dor Abdominal/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/administração & dosagem , Medicina Tradicional Chinesa/métodos , Baço , Estômago , Síndrome , Idoso
17.
Zhongguo Zhong Yao Za Zhi ; 49(4): 1113-1121, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621918

RESUMO

This study systematically collected, analyzed, and evaluated randomized controlled trial(RCT) in the treatment of diabetic foot ulcer(DFU). The aim as provide references for future studies and to enhance the application of clinical evidence. The RCT of DFU treated with Chinese Patent Medicine was obtained and analyzed using the AI-Clinical Evidence Database of Chinese Patent Medicine(AICED-CPM). The analysis was supplemented with data from CNKI, Wanfang, VIP, SinoMed, PubMed, EMbase, Cochrane Library, and Web of Science. A total of 275 RCTs meeting the requirements were retrieved, with only 7 of them having a sample size of 200 or more. These trials involved 66 different Chinese patent medicine including 25 oral medications, 24 Chinese herbal injections, and 17 external drugs. Among the 33 different intervention/control designs identified, the most common design was Chinese patent medicine + conventional treatment vs conventional treatment(86 cases, 31.27%). Out of the 275 articles included in the literature, 50 did not provide information on the specific course of treatment(18.18%). A total of 10 counting indicators(with a frequency of 426) and 36 measuring indicators(with a frequency of 962) were utilized. The methodological quality of the RCT for the treatment of DFU with Chinese patent medicine was found to be low, with deficiencies in blind methods, other bias factors, study registration, and sample size estimation. There were noticeable shortcomings in the reporting of allocation hiding and implementation bias(blind method application). More studies should prioritize trial registration, program design, and strict quality control during implementation to provide valuable data for clinical practice and serve as a reference for future investigations.


Assuntos
Diabetes Mellitus , Pé Diabético , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Humanos , Diabetes Mellitus/tratamento farmacológico , Pé Diabético/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos sem Prescrição/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
18.
Eur J Radiol ; 175: 111452, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604092

RESUMO

OBJECTIVE: To investigate the potential value of quantitative parameters derived from synthetic magnetic resonance imaging (syMRI) for discriminating axillary lymph nodes metastasis (ALNM) in breast cancer patients. MATERIALS AND METHODS: A total of 56 females with histopathologically proven invasive breast cancer who underwent both conventional breast MRI and additional syMRI examinations were enrolled in this study, including 30 patients with ALNM and 26 with non-ALNM. SyMRI has enabled quantification of T1 relaxation time (T1), T2 relaxation time (T2) and proton density (PD). The syMRI quantitative parameters of breast primary tumors before (T1tumor, T2tumor, PDtumor) and after (T1+tumor, T2+tumor, PD+tumor) contrast agent injection were obtained. Similarly, measurements were taken for axillary lymph nodes before (T1LN, T2LN, PDLN) and after (T1+LN, T2+LN, PD+LN) the injection, then theΔT1 (T1-T1+), ΔT2 (T2-T2+), ΔPD (PD-PD+), T1/T2 and T1+/T2+ were calculated. All parameters were compared between ANLM and non-ALNM group. Intraclass correlation coefficient for assessing interobserver agreement. The independent Student's t test or Mann-Whitney U test to determine the relationship between the mean quantitative values and the ALNM. Multivariate logistic regression analyses followed by receiver operating characteristics (ROC) analysis for discriminating ALN status. A P value < 0.05 was considered statistically significant. RESULTS: The short-diameter of lymph nodes (DLN) in ALNM group was significantly longer than that in the non-ALNM group (10.22 ± 3.58 mm vs. 5.28 ± 1.39 mm, P < 0.001). The optimal cutoff value was determined to be 5.78 mm, with an AUC of 0.894 (95 % CI: 0.838-0.939), a sensitivity of 86.7 %, and a specificity of 90.2 %. In syMRI quantitative parameters of breast tumors, T2tumor, ΔT2tumor and ΔPDtumor values showed statistically significant differences between the two groups (P < 0.05). T2tumor value had the best performance in discriminating ALN status (AUC = 0.712), and the optimal cutoff was 90.12 ms, the sensitivity and specificity were 65.0 % and 83.6 % respectively. In terms of syMRI quantitative parameters of lymph nodes, T1LN, T2LN, T1LN/T2LN, T2+LN and ΔT1LN values were significantly different between the two groups (P < 0.05), and their AUCs were 0.785, 0.840, 0.886, 0.702 and 0.754, respectively. Multivariate analyses indicated that the T1LN value was the only independent predictor of ALNM (OR=1.426, 95 % CI: 1.130-1.798, P = 0.039). The diagnostic sensitivity and specificity of T1LN was 86.7 % and 69.4 % respectively at the best cutoff point of 1371.00 ms. The combination of T1LN, T2LN, T1LN/T2LN, ΔT1LN and DLN had better performance for differentiating ALNM and non-ALNM, with AUCs of 0.905, 0.957, 0.964 and 0.897, respectively. CONCLUSION: The quantitative parameters derived from syMRI have certain value for discriminating ALN status in invasive breast cancer, with T2tumor showing the highest diagnostic efficiency among breast lesions parameters. Moreover, T1LN acted as an independent predictor of ALNM.


Assuntos
Axila , Neoplasias da Mama , Linfonodos , Metástase Linfática , Imageamento por Ressonância Magnética , Sensibilidade e Especificidade , Humanos , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Feminino , Axila/diagnóstico por imagem , Pessoa de Meia-Idade , Metástase Linfática/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Adulto , Idoso , Reprodutibilidade dos Testes , Invasividade Neoplásica/diagnóstico por imagem , Meios de Contraste , Interpretação de Imagem Assistida por Computador/métodos , Aumento da Imagem/métodos
19.
Small ; : e2311253, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38456580

RESUMO

A highly viable alternative to lithium-ion batteries for stationary electrochemical energy-storage systems is the potassium dual-ion hybrid capacitor (PIHC), especially toward fast-charging capability. However, the sluggish reaction kinetics of negative electrode materials seriously impedes their practical implementation. In this paper, a new negative electrode Bi@RPC (Nano-bismuth confined in nitrogen- and oxygen-doped carbon with rationally designed pores, evidenced by advanced characterization) is developed, leading to a remarkable electrochemical performance. PIHCs building with the active carbon YP50F positive electrode result in a high operation voltage (0.1-4 V), and remarkably well-retained energy density at a high-power density (11107 W kg-1 at 98 Wh kg-1 ). After 5000 cycles the proposed PHICs still show a superior capacity retention of 92.6%. Moreover, a reversible mechanism of "absorption-alloying" of the Bi@RPC nanocomposite is revealed by operando synchrotron X-ray diffraction and Raman spectroscopy. With the synergistic potassium ions storage mechanism arising from the presence of well-structured pores and nano-sized bismuth, the Bi@RPC electrode exhibits an astonishingly rapid kinetics and high energy density. The results demonstrate that PIHCs with Bi@RPC-based negative electrode is the promising option for simultaneously high-capacity and fast-charging energy storage devices.

20.
Materials (Basel) ; 17(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38473605

RESUMO

In this study, the grain boundary character distribution (GBCD) of a B10 alloy was optimized, employing thermomechanical processing consisting of friction stirring processing (FSP) and annealing treatment. Using electron backscatter diffraction, the effects of rotational speed of FSP and annealing time on the evolution of GBCD were systematically investigated. The GBCD evolution was analyzed concerning various parameters, such as the fraction of low-Σ coincidence site lattice (CSL) boundaries, the average number of grains per twin-related domain (TRD), the length of longest chain (LLC), and the triple junction distribution. The experimental results revealed that the processing of a 1400 rpm rotational speed of FSP followed by annealing at 750 °C for 60 min resulted in the optimum grain boundary engineering (GBE) microstructure with the highest fraction of low-Σ CSL boundaries being 82.50% and a significantly fragmented random boundary network, as corroborated by the highest average number of grains per TRD (14.73) with the maximum LLC (2.14) as well as the highest J2/(1 - J3) value (12.76%). As the rotational speed of FSP increased from 600 rpm to 1400 rpm, the fraction of low-Σ CSL boundaries monotonously increased. The fraction of low-Σ CSL boundaries first increased and then decreased with an increase in annealing time. The key to achieving GBE lies in inhibiting the recrystallization phenomenon while stimulating abundant multiple twinning events through strain-induced boundary migration.

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