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1.
Small ; : e2404127, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38982955

RESUMO

Stannous sulfide (SnS), a conversion-alloying type anode for sodium-ion batteries, is strong Na+ storage activity, a low voltage platform, and high theoretical capacity. However, grain pulverization induced by intolerable volume change and phase aggregation causes quick capacity degradation and unsatisfactory rate capability. Herein, a novel "lasagna" strategy is developed by embedding a SnS layer into the interlayer of an electrochemically robust and electron-active TaS2 to form a misfit layered (SnS)1.15TaS2 superlattice. For Na+ storage, the rationally designed (SnS)1.15TaS2 anode exhibits high specific capacity, excellent rate capability, and robust cycling stability (729 mAh cm-3 at 15 C after 2000 cycles). Moreover, the as-assembled (SnS)1.15TaS2 || Na3V2(PO4)3 full cells achieve robust and fast Na+ storage performance with ≈100% capacity retention after 650 cycles at 15 C, which also demonstrates good low-temperature performance at -20 °C with a capacity retention of 75% and 2 C high-rate charge/discharge ability.

2.
Inorg Chem ; 63(24): 11406-11415, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38835144

RESUMO

Large and rapid lithium storage is hugely demanded for high-energy/power lithium-ion batteries; however, it is difficult to achieve these two indicators simultaneously. Sn-based materials with a (de)alloying mechanism show low working potential and high theoretical capacity, but the huge volume expansion and particle agglomeration of Sn restrict cyclic stability and rate capability. Herein, a soft-in-rigid concept was proposed and achieved by chemical scissoring where a soft Sn-S bond was chosen as chemical tailor to break the Ti-S bond to obtain a loose stacking structure of 1D chain-like Sn1.2Ti0.8S3. The in situ and ex situ (micro)structural characterizations demonstrate that the Sn-S bonds are reduced into Sn domains and such Sn disperses in the rigid Ti-S framework, thus relieving the volume expansion and particle agglomeration by chemical and physical shielding. Benefiting from the merits of large-capacity Sn with an alloying mechanism and high-rate TiS2 with an intercalation mechanism, the Sn1.2Ti0.8S3 anode offers a high specific capacity of 963.2 mA h g-1 at 0.1 A g-1 after 100 cycles and a reversible capacity of 250 mA h g-1 at 10 A g-1 after 3900 cycles. Such a strategy realized by chemical tailoring at the structural unit level would broaden the prospects for constructing joint high-capacity and high-rate LIB anodes.

3.
J Phys Ther Sci ; 36(6): 330-336, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38832217

RESUMO

[Purpose] Falls can significantly affect elderly individuals. However, most current methods used to detect and analyze high-risk conditions make use of simulated falling movements for data collection, which may not accurately represent actual falls. The present study aimed to induce natural falls using visual and auditory stimuli to create unstable walking conditions. [Participants and Methods] Two experiments were performed. The first experiment focused on inducing unstable walking using visual stimuli; whereas, the second experiment combined visual and auditory stimuli. To investigate the effects of stimuli on the induction of unstable walking, our results were compared with those of normal walking conditions. In addition, the two experimental conditions were compared to identify the most effective stimuli. [Results] Both experiments revealed a decrease in step length, an increase in step time and width, and an increase in the coefficient of variation of measurements, indicating an induced walking pattern with a higher risk of falls. Furthermore, combining visual and auditory stimuli caused deterioration of inter-limb coordination, as observed through an increased phase coordination index, thus resulting in further instability during walking. [Conclusion] Visual and auditory stimuli induced unstable walking. In particular, the combination of visual and auditory stimuli with a 0.8-s rhythm increased instability.

4.
Heliyon ; 10(11): e31889, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38912500

RESUMO

Background: Myocardial segmental motion is associated with cardiovascular pathology, often assessed through myocardial strain features. The stability of the motion can be influenced by myocardial fibrosis. This research aimed to explore the complexity metrics (CM) of myocardial segmental motion curves, observe their correlation with late gadolinium enhancement (LGE) transmural extension (TE), and assess diagnostic efficacy combined with segmental strains in different TE segments. Methods: We included 42 myocardial infarction patients, dividing images into 672 myocardial segments (208 remote, 384 viable, and 80 unviable segments based on TE). Radial and circumferential segmental strain, along with CM for motion curves, were extracted. Correlation between CM and LGE, as well as the potential distinguishing role of CM, was evaluated using Pearson correlation, univariate linear regression (F-test), multivariate regression analysis (T-test), area under curve (AUC), machine learning models, and DeLong test. Results: All CMs showed significant linear correlation with TE (P < 0.001). Six CMs were correlated with TE (r > 0.3), with radial frequency drift (FD) displayed the strongest correlation (r = 0.496, P < 0.001). Radial and circumferential FD significantly differed in higher TE myocardium than in remote segments (P < 0.05). Radial FD had practical diagnostic efficacy (remote vs. unviable AUC = 0.89, viable vs. unviable AUC = 0.77, remote vs. viable AUC = 0.65). Combining CM with segmental strain features boosted diagnostic efficacy than models using only segmental strain features (DeLong test, P < 0.05). Conclusions: The CM of myocardial motion curves has been associated with LGE infarction, and combining CM with strain features improves the diagnosis of different myocardial LGE infarction degrees.

5.
Diagnostics (Basel) ; 14(10)2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38786304

RESUMO

BACKGROUND: The aim of this study was to exploit integrated PET/MRI to simultaneously evaluate the morphological, component, and metabolic features of advanced atherosclerotic plaques and explore their incremental value. METHODS: In this observational prospective cohort study, patients with advanced plaque in the carotid artery underwent 18F-FDG PET/MRI. Plaque morphological features were measured, and plaque component features were determined via MRI according to AHA lesion-types. Maximum standardized uptake values (SUVmax) and tissue to background ratio (TBR) on PET were calculated. Area under the receiver-operating characteristic curve (AUC) and net reclassification improvement (NRI) were used to compare the incremental contribution of FDG uptake when added to AHA lesion-types for symptomatic plaque classification. RESULTS: A total of 280 patients with advanced plaque in the carotid artery were recruited. A total of 402 plaques were confirmed, and 87 of 402 (21.6%) were symptomatic plaques. 18F-FDG PET/MRI was performed a mean of 38 days (range 1-90) after the symptom. Increased stenosis degree (61.5% vs. 50.0%, p < 0.001) and TBR (2.96 vs. 2.32, p < 0.001) were observed in symptomatic plaques compared with asymptomatic plaques. The performance of the combined model (AHA lesion type VI + stenosis degree + TBR) for predicting symptomatic plaques was the best among all models (AUC = 0.789). The improvement of the combined model (AHA lesion type VII + stenosis degree + TBR) over AHA lesion type VII model for predicting symptomatic plaques was the highest (AUC = 0.757/0.454, combined model/AHA lesion type VII model), and the NRI was 50.7%. CONCLUSIONS: Integrated PET/MRI could simultaneously evaluate the morphological component and inflammation features of advanced atherosclerotic plaques and provide supplementary optimization information over AHA lesion-types for identifying vulnerable plaques in atherosclerosis subjects to achieve further stratification of stroke risk.

6.
World Neurosurg ; 185: e1330-e1337, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38521216

RESUMO

OBJECTIVE: To assess the effectiveness and safety of neurological interventions using the right transradial approach (R-TRA) in patients with aberrant right subclavian artery (ARSA). METHODS: We retrospectively analyzed cases that underwent cerebral angiography and interventions at Huangpi District People's Hospital from January 2023 to July 2023. Out of 335 cases, 5 patients with ARSA were identified. RESULTS: All 5 cases underwent diagnostic cerebral angiography via R-TRA. Two of the patients received interventions via R-TRA: 1 underwent right internal carotid artery balloon dilation angioplasty, while another underwent left vertebral artery stenting. No surgery-related complications were observed during these procedures. CONCLUSIONS: R-TRA proves to be a safe and effective option for neuro-interventional surgery in patients with ARSA.


Assuntos
Anormalidades Cardiovasculares , Angiografia Cerebral , Artéria Subclávia , Humanos , Artéria Subclávia/anormalidades , Artéria Subclávia/cirurgia , Artéria Subclávia/diagnóstico por imagem , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Anormalidades Cardiovasculares/cirurgia , Anormalidades Cardiovasculares/diagnóstico por imagem , Angiografia Cerebral/métodos , Adulto , Artéria Radial/cirurgia , Artéria Radial/diagnóstico por imagem , Angioplastia com Balão/métodos , Stents , Idoso , Aneurisma/cirurgia , Aneurisma/diagnóstico por imagem , Resultado do Tratamento
7.
Quant Imaging Med Surg ; 14(3): 2441-2454, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38545070

RESUMO

Background: It is frequently observed that patients with first-ever acute ischemic stroke (AIS) have a common occurrence of asymptomatic coronary artery disease (CAD). This condition is associated with a poor prognosis. Early detection and recognition of asymptomatic CAD in first-ever AIS patients may optimize the clinical management and ultimately lead to improved outcomes. The aim of this study was to investigate the role of aortic arch plaque (AAP) detected through combined computed tomography angiography (CTA) as an early predictor of asymptomatic CAD in patients with first-ever AIS without prior diagnosis of CAD. Methods: A cross-sectional study was conducted at Xuanwu Hospital, Capital Medical University from January 2019 to December 2021, involving patients with first-ever AIS caused by large arterial atherosclerosis. Patients with a history of recognized cardiovascular disease, nonatherosclerotic arterial stenosis, atrial fibrillation related to cardioembolism, and complete carotid occlusions were excluded. The study utilized a combined coronary and cervicocephalic CTA to evaluate atherosclerosis in the cervicocephalic, aortic, and coronary arteries simultaneously. First-ever AIS patients without prior diagnosis of CAD were divided into 2 groups: 1 with asymptomatic CAD detected through CTA and the other without. Multivariate logistic regression was used to identify independent risk factors associated with the presence of asymptomatic CAD, including aortic arch, cervical and intracranial atherosclerotic characteristics (e.g., vascular stenosis, plaque thickness, extent, and complexity). Results: Among 182 AIS patients, 84 (46.2%) had asymptomatic CAD. Increased aortic arch plaque (AAP) thickness per millimeter [adjusted odds ratio (aOR): 1.26; 95% confidence interval (CI): 1.08-1.47], presence of severe AAP (aOR: 4.24; 95% CI: 1.59-12.03), mixed AAP (aOR: 2.65; 95% CI: 1.09-6.62), and ulcerative AAP (aOR: 11.76; 95% CI: 2.05-222.84) raised the risk of asymptomatic CAD in stroke patients, independent of other factors. The combination of ulcerative AAP, diabetes mellitus, and smoking could predict asymptomatic CAD with an area under the receiver operating characteristic curve (AUC) of 0.71 (95% CI: 0.64-0.79; P<0.001). Ulcerative AAP was found to be more valuable than cervicocephalic atherosclerotic characteristics for predicting asymptomatic CAD in first-ever AIS patients. Conclusions: The presence of ulcerative AAP was associated with asymptomatic CAD in first-ever AIS patients. As an early systemic atherosclerosis feature, ulcerative AAP is probably a more valuable indicator than cervicocephalic atherosclerotic characteristics for predicting asymptomatic CAD in AIS patients.

8.
J Am Chem Soc ; 146(11): 7352-7362, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38447048

RESUMO

Knowledge of structure-property relationships in solids with intrinsic low thermal conductivity is crucial for fields such as thermoelectrics, thermal barrier coatings, and refractories. Herein, we propose a new "rigidness in softness" structural scheme for intrinsic low lattice thermal conductivity (κL), which embeds rigid clusters into the soft matrix to induce large lattice anharmonicity, and accordingly discover a new series of chalcogenides Pt3Bi4Q9 (Q = S, Se). Pt3Bi4S9-xSex (x = 3, 6) achieved an intrinsic ultralow κL down to 0.39 W/(m K) at 773 K, which is considerably low among the Bi chalcogenide thermoelectric materials. Pt3Bi4Q9 contains the rigid cubic [Pt6Q12]12- clusters embedded in the soft Bi-Q sublattice, involving multiple bonding interactions and vibration hierarchy. The hierarchical structure yields a large lattice anharmonicity with high Grüneisen parameters (γ) 1.97 of Pt3Bi4Q9, as verified by the effective scatter of low-lying optical phonons toward heat-carrying acoustic phonons. Consequently, the rigid-soft coupling significantly inhibits heat propagation, exhibiting low acoustic phonon frequencies (∼25 cm-1) and Debye temperatures (ΘD = 170.4 K) in Pt3Bi4Se9. Owing to the suppressed κL and considerable power factor (PF), the ZT value of Pt3Bi4S6Se3 can reach 0.56 at 773 K without heavy carrier doping, which is competitive among the pristine Bi chalcogenides. Theoretical calculations predicted a large potential for performance improvement via proper doping, indicating the great potential of this structure type for promising thermoelectric materials.

9.
Small ; 20(29): e2311638, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38342598

RESUMO

Potassium-ion batteries (PIBs) have attracted much attention due to their low production cost and abundant resources. Germanium is a promising alloying-type anode with a high theoretical capacity for PIBs, yet suffering significant volume expansion and sluggish potassium-ion transport kinetics. Herein, a rational strategy is formulated to disperse Ge atoms into transition metal V-S sulfide frameworks to form a loosely packed and metallic GeV4S8 medium. The theoretical prediction shows that GeV4S8 is conducive to the adsorption and diffusion of K+. The V-S frameworks provide fast ion/electron diffusion channels and also help to buffer the volume expansion during K+ insertion. In situ and ex situ characterizations manifest that KGe alloy clusters are constrained and dispersed by potassiated VS2 topological structure during discharging, and revert to the original GeV4S8 after charging. Consequently, as a novel anode for PIBs, GeV4S8 provides a high specific capacity of ≈400 mAh g-1 at 0.5 C, maintaining 160 mAh g-1 even at 12.5 C and ≈80% capacity after 1000 cycles at 5 C, superior to most of the state-of-the-art anode materials. The proposed strategy of combining alloy and intercalation dual-functional units is expected to open up a new way for high-capacity and high-rate anode for PIBs.

10.
JAMA ; 331(10): 840-849, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38329440

RESUMO

Importance: It is uncertain whether intravenous methylprednisolone improves outcomes for patients with acute ischemic stroke due to large-vessel occlusion (LVO) undergoing endovascular thrombectomy. Objective: To assess the efficacy and adverse events of adjunctive intravenous low-dose methylprednisolone to endovascular thrombectomy for acute ischemic stroke secondary to LVO. Design, Setting, and Participants: This investigator-initiated, randomized, double-blind, placebo-controlled trial was implemented at 82 hospitals in China, enrolling 1680 patients with stroke and proximal intracranial LVO presenting within 24 hours of time last known to be well. Recruitment took place between February 9, 2022, and June 30, 2023, with a final follow-up on September 30, 2023. Interventions: Eligible patients were randomly assigned to intravenous methylprednisolone (n = 839) at 2 mg/kg/d or placebo (n = 841) for 3 days adjunctive to endovascular thrombectomy. Main Outcomes and Measures: The primary efficacy outcome was disability level at 90 days as measured by the overall distribution of the modified Rankin Scale scores (range, 0 [no symptoms] to 6 [death]). The primary safety outcomes included mortality at 90 days and the incidence of symptomatic intracranial hemorrhage within 48 hours. Results: Among 1680 patients randomized (median age, 69 years; 727 female [43.3%]), 1673 (99.6%) completed the trial. The median 90-day modified Rankin Scale score was 3 (IQR, 1-5) in the methylprednisolone group vs 3 (IQR, 1-6) in the placebo group (adjusted generalized odds ratio for a lower level of disability, 1.10 [95% CI, 0.96-1.25]; P = .17). In the methylprednisolone group, there was a lower mortality rate (23.2% vs 28.5%; adjusted risk ratio, 0.84 [95% CI, 0.71-0.98]; P = .03) and a lower rate of symptomatic intracranial hemorrhage (8.6% vs 11.7%; adjusted risk ratio, 0.74 [95% CI, 0.55-0.99]; P = .04) compared with placebo. Conclusions and Relevance: Among patients with acute ischemic stroke due to LVO undergoing endovascular thrombectomy, adjunctive methylprednisolone added to endovascular thrombectomy did not significantly improve the degree of overall disability. Trial Registration: ChiCTR.org.cn Identifier: ChiCTR2100051729.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Feminino , Humanos , Idoso , Método Duplo-Cego , Trombectomia/efeitos adversos , Hemorragias Intracranianas , Metilprednisolona/efeitos adversos
11.
Appl Opt ; 63(3): 681-691, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38294380

RESUMO

Particle dispersed coatings with gradient distributions, resulting from either gravity or artificial control, are frequently encountered in practical applications. However, most current studies investigating the optical properties of coatings use the uniform model (uniform single layer assumption), overlooking the gradient distribution effects. Given the pervasiveness of gradient distributions and the widespread use of the uniform model, it is imperative to evaluate applicability conditions of the uniform model in practical applications. In this work, we comprehensively investigate the quantitative performance of the uniform model in predicting the infrared optical properties of coatings with gradient distributions of particle volume fraction using the superposition T-matrix method. The results show that the gradient distribution of particle volume fraction has a limited impact on the emissivity properties of T i O 2-PDMS coatings in the midwavelength-infrared (MWIR) and long-wavelength-infrared (LWIR) bands, which validates the uniform model for the gradient coatings with weakly scattering dielectric particles. However, the uniform model can yield significant inaccuracies in estimating the emissivity properties of Al-PDMS coatings with gradient distributions in the MWIR and LWIR bands. To accurately estimate the emissivity of such gradient coatings with the scattering metallic particles, meticulous modeling of the particle volume fraction distribution is essential.

12.
ESC Heart Fail ; 11(1): 444-455, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38037178

RESUMO

AIMS: The present study aimed to phenotype the cerebral structural and glucose metabolic alterations in patients with heart failure (HF) using simultaneous positron emission tomography (PET)/magnetic resonance (MR) and to investigate their relationship to cardiac biomarkers and cognitive performance. METHODS AND RESULTS: Forty-two HF patients caused by ischaemic heart disease (mean age 67.2 ± 10.4, 32 males) and 32 age- and sex-matched healthy volunteers (mean age 61.3 ± 4.8, 18 males) were included in this study. Participants underwent simultaneous cerebral fluorine-18 (18 F) fluorodeoxyglucose PET/MR followed by cardiac MR scan, and neuropsychological scores were obtained to assess cognitive performance. The grey matter volume (GMV) and standardized uptake value ratio (SUVR) were calculated to examine cerebral structural and metabolic alterations. Cardiac biomarkers included cardiac MR parameters and cardiac serum laboratory tests. Mediation analysis was performed to explore the associations among cerebral alterations, cardiac biomarkers, and cognitive performance. HF patients demonstrated notable cognitive impairment compared with normal controls (P < 0.001). Furthermore, HF patients exhibited regional brain hypometabolism in the bilateral calcarine cortex, caudate nucleus, thalamus, hippocampus, precuneus, posterior cingulate cortex, lingual and olfactory cortex, and GMV reduction in bilateral thalamus and hippocampus (cluster level at P < 0.05, Gaussian random field correction). The SUVR of the hypometabolic brain regions was correlated with the Montreal Cognitive Assessment (MoCA) scores (r = 0.55, P = 0.038) and cardiac stroke volume (r = 0.49, P = 0.002). Cerebral hypometabolism played a key role in the relationship between the decreased stroke volume and MoCA scores, with a mediation effect of 33.2%. CONCLUSIONS: HF patients suffered cerebral metabolic and structural alterations in regions associated with cognition. The observed correlation between cardiac stroke volume and cognitive impairment underscored the potential influence of cerebral hypometabolism, suggesting that cerebral hypometabolism due to chronic systemic hypoperfusion may significantly contribute to cognitive impairment in HF patients.


Assuntos
Disfunção Cognitiva , Insuficiência Cardíaca , Masculino , Humanos , Volume Sistólico , Fluordesoxiglucose F18 , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/diagnóstico , Biomarcadores
13.
Metabolites ; 13(11)2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37999259

RESUMO

α-Amanitin is a representative toxin found in the Amanita genus of mushrooms, and the consumption of mushrooms containing α-Amanitin can lead to severe liver damage. In this study, we conduct toxicological experiments to validate the protective effects of Ganoderic acid A against α-amanitin-induced liver damage. By establishing animal models with different durations of Ganoderic acid A treatment and conducting a metabolomic analysis of the serum samples, we further confirmed the differences in serum metabolites between the AMA+GA and AMA groups. The analysis of differential serum metabolites after the Ganoderic acid A intervention suggests that Ganoderic acid A may intervene in α-amanitin-induced liver damage by participating in the regulation of retinol metabolism, tyrosine and tryptophan biosynthesis, fatty acid biosynthesis, sphingosine biosynthesis, spermidine and spermine biosynthesis, and branched-chain amino acid metabolism. This provides initial insights into the protective intervention mechanisms of GA against α-amanitin-induced liver damage and offers new avenues for the development of therapeutic drugs for α-Amanitin poisoning.

14.
Micromachines (Basel) ; 14(11)2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-38004933

RESUMO

Wide-bandgap gallium nitride (GaN)-based semiconductors offer significant advantages over traditional Si-based semiconductors in terms of high-power and high-frequency operations. As it has superior properties, such as high operating temperatures, high-frequency operation, high breakdown electric field, and enhanced radiation resistance, GaN is applied in various fields, such as power electronic devices, renewable energy systems, light-emitting diodes, and radio frequency (RF) electronic devices. For example, GaN-based high-electron-mobility transistors (HEMTs) are used widely in various applications, such as 5G cellular networks, satellite communication, and radar systems. When a current flows through the transistor channels during operation, the self-heating effect (SHE) deriving from joule heat generation causes a significant increase in the temperature. Increases in the channel temperature reduce the carrier mobility and cause a shift in the threshold voltage, resulting in significant performance degradation. Moreover, temperature increases cause substantial lifetime reductions. Accordingly, GaN-based HEMTs are operated at a low power, although they have demonstrated high RF output power potential. The SHE is expected to be even more important in future advanced technology designs, such as gate-all-around field-effect transistor (GAAFET) and three-dimensional (3D) IC architectures. Materials with high thermal conductivities, such as silicon carbide (SiC) and diamond, are good candidates as substrates for heat dissipation in GaN-based semiconductors. However, the thermal boundary resistance (TBR) of the GaN/substrate interface is a bottleneck for heat dissipation. This bottleneck should be reduced optimally to enable full employment of the high thermal conductivity of the substrates. Here, we comprehensively review the experimental and simulation studies that report TBRs in GaN-on-SiC and GaN-on-diamond devices. The effects of the growth methods, growth conditions, integration methods, and interlayer structures on the TBR are summarized. This study provides guidelines for decreasing the TBR for thermal management in the design and implementation of GaN-based semiconductor devices.

15.
Heliyon ; 9(4): e14738, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37151654

RESUMO

[This corrects the article DOI: 10.1016/j.heliyon.2023.e13968.].

16.
Quant Imaging Med Surg ; 13(5): 3050-3065, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37179938

RESUMO

Background: This meta-analysis evaluated the diagnostic accuracy of contrast-enhanced dual-energy computed tomography (DECT) for detecting metastatic lymph nodes in patients with cancer. Methods: PubMed, Embase and Cochrane Library databases were searched for literature published from database inception until September 2022. Only studies that investigated the diagnostic accuracy of DECT for metastatic lymph nodes in patients with malignant tumors and surgically removed metastatic lymph nodes for pathological confirmation were included. The quality of the included studies was evaluated using the Quality Assessment of Diagnostic Accuracy Studies tool. The threshold effect was determined by calculating Spearman correlation coefficients and summary receiver operating characteristic (SROC) curve patterns. Deeks test was used to assess publication bias. Results: All of the included studies were observational studies. A total of 16 articles involving 984 patients were included (2,577 lymph nodes) in this review. A total of 15 variables were included in the meta-analysis, including 6 individual parameters and 9 combined parameters. Normalized iodine concentration (NIC) in the arterial phase combined with the slope in the arterial phase showed better identification of metastatic lymph nodes. The spearman correlation coefficient was -0.371 (P=0.468), and the SROC curve did not show a "shoulder-arm" shape, suggesting that there was no threshold effect and that heterogeneity was present. The combined sensitivity was 94% [95% confidence interval (CI): 86-98%], the specificity was 74% (95% CI: 52-88%), and the area under the curve was 0.94. The Deeks test suggested no significant publication bias in the included studies (P=0.06). Conclusions: NIC in arterial phase combined with the slope in the arterial phase has some diagnostic value in differentiating between metastatic and benign lymph nodes, but this should be further evaluated in additional studies with rigorous design and high homogeneity.

18.
Nanomaterials (Basel) ; 13(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36985924

RESUMO

Infrared (IR) stealth plays a vital role in the modern military field. With the continuous development of detection technology, multi-band (such as near-IR laser and middle-IR) compatible IR stealth is required. Combining rigorous coupled wave analysis (RCWA) with Deep Learning (DL), we design a Ge/Ag/Ge multilayer circular-hole metasurface capable of multi-band IR stealth. It achieves low average emissivity of 0.12 and 0.17 in the two atmospheric windows (3~5 µm and 8~14 µm), while it achieves a relatively high average emissivity of 0.61 between the two atmospheric windows (5~8 µm) for the purpose of radiative thermal management. Additionally, the metasurface has a narrow-band high absorptivity of 0.88 at the near-infrared wavelength (1.54 µm) for laser guidance. For the optimized structure, we also analyze the potential physical mechanisms. The structure we optimized is geometrically simple, which may find practical applications aided with advanced nano-fabrication techniques. Also, our work is instructive for the implementation of DL in the design and optimization of multifunctional IR stealth materials.

19.
Heliyon ; 9(3): e13968, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36895340

RESUMO

Background: Blunt cerebrovascular injuries are rare and serious complications of trauma that can lead to cerebral vascular dissection or aneurysm. Improving awareness of blunt cerebrovascular injuries and using computed tomography angiography to pre-screen patients at high risk is recommended by current guidelines to prevent the occurrence of ischemic stroke complications. Case description: A 32-year-old male patient was admitted to the hospital following neck trauma accompanied by stroke symptoms. Imaging revealed intimal injury of the right common carotid artery and acute cerebral infarction. After an endarterectomy and repair, the vascular lumen obstruction resolved, blood flow was restored, and the patient's condition stabilized. Conclusion: Blunt cerebrovascular injury has been seriously neglected in clinical practice. Delayed or under-diagnosis of blunt cerebrovascular injury can result large strokes. Standardized treatment protocols, which include the screening and grading of blunt cerebrovascular injury, may reduce the risk of permanent neurological dysfunction, and even death, in patients.

20.
J Int Med Res ; 51(2): 3000605231154379, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36772988

RESUMO

Spontaneous internal carotid artery dissection (ICAD) is a rare disease and an important cause of stroke in young patients. The presentation of ICAD is variable and atypical. We have used three-dimensional T1-weighted volume isotropic turbo spin-echo acquisition to help diagnose ICAD. ICAD should be considered in young patients presenting with relevant symptoms in an emergency setting. We herein report ICAD with an unexplained onset in two patients. Neither had a history of large or small cervical trauma, but both had a history of hypertension. The first patient was a 33-year-old man who presented with upper extremity numbness and mobility impairment, and the second patient was a 40-year-old man with onset of visual impairment. There were no obvious triggers in either case. Both patients were diagnosed with ICAD by blood vessel examination. However, their prognoses differed. The first patient recovered after endovascular therapy, whereas the second patient was successfully managed with medical treatment. ICAD can cause different symptoms depending on where the dissection occurs. Clinicians must be aware of the different clinical manifestations of ICAD, make the correct diagnosis in a timely manner, make appropriate treatment plans according to the patient's condition, and strive for timely recanalization of the blood vessels.


Assuntos
Dissecação da Artéria Carótida Interna , Hipertensão , Acidente Vascular Cerebral , Masculino , Humanos , Adulto , Dissecação da Artéria Carótida Interna/diagnóstico , Dissecação da Artéria Carótida Interna/diagnóstico por imagem , Acidente Vascular Cerebral/etiologia , Prognóstico , Hipertensão/complicações
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