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1.
ACS Nano ; 18(11): 8350-8359, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38465598

RESUMO

The low ionic conductivities of aprotic electrolytes hinder the development of extreme fast charging technologies and applications at low temperatures for lithium-ion batteries (LIBs). Herein, we present an electrolyte with LiFSI in acetone (DMK). In DMK electrolytes, the solvation number is three, and solvent-separated ion pairs (SSIPs) are the dominant structure, which is largely different from other linear aprotic electrolytes where salts primarily exist as contact ion pairs (CIPs). With incompact solvation structures due to the weak solvation ability of DMK with Li+, the ionic conductivity reaches 45 mS/cm at room temperature. The percentage of SSIPs increases as temperatures decrease in DMK electrolytes, which is totally different from the carbonate-based electrolytes but greatly beneficial to low-temperature ionic conductivity. With the appropriate addition of VC and FEC, DMK-based electrolytes still exhibit a superhigh ionic conductivity. Even at -40 °C, the ionic conductivity is greater than 10 mS/cm. With DMK-based electrolytes, LIBs with thick LiFePO4 electrodes can be cycled at high rates and at low temperatures.

2.
J Colloid Interface Sci ; 663: 270-279, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38401447

RESUMO

A new type of self-supporting multi-channel Janus carbon fibers with efficient water splitting has been successfully manufactured using a specially designed parallel spinneret through electrospinning technology and subsequent carbonization technique. Every single Janus fiber composes of a half side of Mo2C and the other half side of Ni components as Mo2C, Ni embedded in N-doped multi-channel Janus carbon fibers ([Mo2C/C]//[Ni/C]-NMCFs) for overall water splitting. Under optimized condition, the hydrogen evolution reaction overpotential of [Mo2C/C]//[Ni/C]-NMCFs (62 mV) is just 24 mV higher than 20 wt% Pt/C (38 mV) at a current density of 10 mA cm-2. Furthermore, it achieves current density of 10 mA cm-2 to require an overpotential of 324 mV for oxygen evolution reaction. Additionally, the cell assembled by the identical [Mo2C/C]//[Ni/C]-NMCFs catalyst as both the cathode and anode needs only 1.607 V at a current density of 10 mA cm-2, which is only 0.022 V higher than that of Pt/C-IrO2 electrodes. Moreover, [Mo2C/C]//[Ni/C]-NMCFs catalyst also exhibits a long-term stability. The synergistic effect and unique heterostructure of Mo2C and Ni enhance the catalytic activity.

3.
J Endourol ; 38(3): 262-269, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38205660

RESUMO

Purpose: To evaluate functional outcomes of robot-assisted ureteroplasty with labial mucosa grafting for long proximal ureteral stenosis (LPUS) in children and adolescents. Methods: Included in this study were 15 patients who underwent robot-assisted ureteroplasty with labial mucosal grafting in our center between July 2017 and September 2021. The left affected stenotic ureter was repaired using labial mucosal grafting. If the ureter was simply strictured but not obliterated, the ureter was spatulated longitudinally along the ventral side and the labial mucosa graft was interposed and anastomosed in a continuous manner. Faced with the obliterated segment, it was excised and the spatulated portion re-anastomosed with a pelvic flap as the dorsal wall. The labial mucosa graft was placed as the ventral wall. The preoperative clinical data and follow-up outcomes were collected and evaluated. Results: Labial mucosa graft onlay ureteroplasty was well performed in all the 15 patients with no occurrence of intraoperative complications or surgical conversion. Five patients underwent an onlay ureteroplasty, and 10 patients underwent a dorsally augmented pelvic flap anastomotic ureteroplasty. The mean (range) stricture length was 7.1 (3-10) cm. The mean operative time was 371.2 (216-480) minutes, and the median blood loss was 40 mL. At the median follow-up of 35 months (range 12-58 months), the overall success rate was 93.3%. Conclusions: Labial mucosa grafting appears to be safe and feasible for repairing long ureteral strictures in pediatric and adolescent patients. Our experience may provide beneficial references and conveniences to solve complex problems in LPUS. This study was approved by the institutional review board, and written informed consent was obtained from each participant (ethics number: 2017-30).


Assuntos
Robótica , Ureter , Obstrução Ureteral , Humanos , Adolescente , Criança , Ureter/cirurgia , Constrição Patológica/cirurgia , Estudos Retrospectivos , Obstrução Ureteral/cirurgia , Mucosa Bucal/transplante , Resultado do Tratamento
4.
Nano Lett ; 24(1): 417-423, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38149580

RESUMO

Spectrally stable pure-red perovskite quantum dots (QDs) with low lead content are essential for high-definition displays but are difficult to synthesize due to QD self-purification. Here, we make use of entropy-driven quantum-confined pure-red perovskite QDs to fabricate light-emitting diodes (LEDs) that have low toxicity and are efficient and spectrum-stable. Based on experimental data and first-principles calculations, multiple element alloying results in a 60% reduction in lead content while improving QD entropy to promote crystal stability. Entropy-driven QDs exhibit photoluminescence with 100% quantum yields and single-exponential decay lifetimes without alteration of their morphology or crystal structure. The pure-red LEDs utilizing entropy-driven QDs have spectrally stable electroluminescence, achieving a brightness of 4932 cd/m2, a maximum external quantum efficiency of over 20%, and a 15-fold longer operational lifetime than the CsPbI3 QD-based LEDs. These achievements demonstrate that entropy-driven QDs can mitigate local compositional heterogeneity and ion migration.

5.
Angew Chem Int Ed Engl ; 62(43): e202310973, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37667678

RESUMO

Full understanding to the origin of the catalytic performance of a supported nanocatalyst from the points of view of both the active component and support is significant for the achievement of high performance. Herein, based on a model electrocatalyst of single-iridium-atom-doped iron (Fe)-based layered double hydroxides (LDH) for oxygen evolution reaction (OER), we reveal the first completed origin of the catalytic performance of such supported nanocatalysts. Specially, besides the activity enhancement of Ir sites by LDH support, the stability of surface Fe sites is enhanced by doped Ir sites: DFT calculation shows that the Ir sites can reduce the activity and enhance the stability of the nearby Fe sites; while further finite element simulations indicate, the stability enhancement of distant Fe sites could be attributed to the much low concentration of OER reactant (hydroxyl ions, OH- ) around them induced by the much fast consumption of OH- on highly active Ir sites. These new findings about the interaction between the main active components and supports are applicable in principle to other heterogeneous nanocatalysts and provide a completed understanding to the catalytic performance of heterogeneous nanocatalysts.

6.
Urol Case Rep ; 50: 102514, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37601834

RESUMO

A 3-year-old girl with a chief complaint of lower urinary tract symptoms (LUTS) for 3 years was admitted in our center. Urinary ultrasonography showed left hydronephrosis with ureteral dilatation and left solitary kidney. Voiding cystourethrography indicated left vesicoureteral reflux and trabeculated bladder wall. Urodynamics study revealed the low flow rate and high detrusor pressure. Cystoscopy showed trabeculated bladder wall with elevation of the bladder neck. Then we performed transurethral bladder neck incision tentatively. The patient recovered from LUTS and the upper urinary tract dilation disappeared postoperatively.

7.
ACS Nano ; 17(17): 16827-16839, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37582222

RESUMO

Severe capacity/voltage fading still poses substantial obstacles in the commercial applications of Li-rich layered oxides, which stems from the aggregation of Li2MnO3-like domains and unstable surface structure. Here, we report highly stabilized Co-free Li1.2Ni0.2Mn0.6O2 with uniformly dispersed Li2MnO3-like domains and a protective rock-salt structure shell by reducing the oxygen partial pressure during high-temperature calcination. Experimental characterizations and DFT calculations reveal that the uniformly dispersed and small-sized Li2MnO3-like domains suppress the peroxidation of lattice oxygen, enabling highly reversible oxygen redox and excellent structural stability. Moreover, the induced rock-salt structure shell significantly restrains lattice oxygen release, TM dissolution, and interfacial side reactions, thereby improving the interfacial stability and facilitating Li+ diffusion. Consequently, the obtained Li1.2Ni0.2Mn0.6O2 which was calcinated under an oxygen partial pressure of 0.1% (LNMO-0.1) delivers a high reversible capacity of 276.5 mAh g-1 at 0.1 C with superior cycling performance (a capacity retention rate of 85.4% after 300 cycles with a small voltage fading rate of 0.76 mV cycle-1) and excellent thermal stability. This work links the synthesis conditions with the domain structure and electrochemical performance of Li-rich cathode materials, providing some insights for designing high-performance Li-rich cathodes.

8.
Radiat Oncol ; 18(1): 116, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37434171

RESUMO

PURPOSE: To investigate the feasibility and performance of deep learning (DL) models combined with plan complexity (PC) and dosiomics features in the patient-specific quality assurance (PSQA) for patients underwent volumetric modulated arc therapy (VMAT). METHODS: Total of 201 VMAT plans with measured PSQA results were retrospectively enrolled and divided into training and testing sets randomly at 7:3. PC metrics were calculated using house-built algorithm based on Matlab. Dosiomics features were extracted and selected using Random Forest (RF) from planning target volume (PTV) and overlap regions with 3D dose distributions. The top 50 dosiomics and 5 PC features were selected based on feature importance screening. A DL DenseNet was adapted and trained for the PSQA prediction. RESULTS: The measured average gamma passing rate (GPR) of these VMAT plans was 97.94% ± 1.87%, 94.33% ± 3.22%, and 87.27% ± 4.81% at the criteria of 3%/3 mm, 3%/2 mm, and 2%/2 mm, respectively. Models with PC features alone demonstrated the lowest area under curve (AUC). The AUC and sensitivity of PC and dosiomics (D) combined model at 2%/2 mm were 0.915 and 0.833, respectively. The AUCs of DL models were improved from 0.943, 0.849, 0.841 to 0.948, 0.890, 0.942 in the combined models (PC + D + DL) at 3%/3 mm, 3%/2 mm and 2%/2 mm, respectively. A best AUC of 0.942 with a sensitivity, specificity and accuracy of 100%, 81.8%, and 83.6% was achieved with combined model (PC + D + DL) at 2%/2 mm. CONCLUSIONS: Integrating DL with dosiomics and PC metrics is promising in the prediction of GPRs in PSQA for patients underwent VMAT.


Assuntos
Aprendizado Profundo , Radioterapia de Intensidade Modulada , Humanos , Estudos Retrospectivos , Algoritmos , Área Sob a Curva
9.
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi ; 37(7): 782-787, 2023 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-37460172

RESUMO

Objective: To investigate the short-term effectiveness of calcaneal lateral displacement osteotomy with lateral ligament repair in the treatment of Takakura stage Ⅱ varus-type ankle arthritis. Methods: A retrospective analysis was performed on the clinical data of 13 patients with Takakura stage Ⅱ varus-type ankle arthritis treated with calcaneal lateral displacement osteotomy with lateral ligament repair between January 2016 and December 2020. There were 6 males and 7 females aged 31-65 years, with an average age of 53.6 years. The preoperative tibial-ankle surface angle (TASA) was (88.13±1.01)°, medial distal tibial angle (MDTA) was (86.36±1.49)°, tibial talar surface angle (TTSA) was (6.03±1.63)°, talar tilting angle (TTA) was (81.95±2.15)°, and tibiocalcaneal axis angle (TCAA) was (-5.74±6.81)°. The preoperative American Orthopedic Foot and Ankle Society (AOFAS) score was 56.3±7.1 and the pain visual analogue scale (VAS) score was 3.7±0.5. AOFAS scores, VAS scores, TTSA, TTA, and TCAA were compared between pre- and post-operatively. Results: All 13 patients were followed up 14-41 months, with an average of 28.7 months. The osteotomies healed in all patients. The last follow-up revealed TTA, TTSA, and TCAA to be (88.27±1.19)°, (-0.13±1.37)°, and (2.09±5.10)° respectively, the AOFAS score was 84.3±4.2 and the VAS score was 0.7±0.5, all showing significant improvement when compared to preoperative values ( P<0.05). Conclusion: For patients with Takakura stage Ⅱ varus-type ankle arthritis, calcaneal lateral displacement osteotomy with lateral ligament repair can correct the lower limb force line, regain ankle stability, and achieving good short-term effectiveness.


Assuntos
Ligamentos Colaterais , Osteoartrite , Masculino , Feminino , Humanos , Pessoa de Meia-Idade , Tornozelo , Estudos Retrospectivos , Articulação do Tornozelo/cirurgia , Osteoartrite/cirurgia , Osteotomia , Resultado do Tratamento
10.
Radiol Med ; 128(6): 679-688, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37188857

RESUMO

OBJECTIVES: The value of adding radiotherapy (RT) is still unclear for patients with gastric cancer (GC) after D2 lymphadenectomy. The purpose of this study is to predict and compare the overall survival (OS) and disease-free survival (DFS) of GC patients treated by chemotherapy and chemoradiation based on contrast-enhanced CT (CECT) radiomics. METHODS: A total of 154 patients treated by chemotherapy and chemoradiation in authors' hospital were retrospectively reviewed and randomly divided into the training and testing cohorts (7:3). Radiomics features were extracted from contoured tumor volumes in CECT using the pyradiomics software. Radiomics score and nomogram with integrated clinical factors were developed to predict the OS and DFS and evaluated with Harrell's Consistency Index (C-index). RESULTS: Radiomics score achieved a C index of 0.721(95%CI: 0.681-0.761) and 0.774 (95%CI: 0.738-0.810) in the prediction of DFS and OS for GC patients treated by chemotherapy and chemoradiation, respectively. The benefits of additional RT only demonstrated in subgroup of GC patients with Lauren intestinal type and perineural invasion (PNI). Integrating clinical factors further improved the prediction ability of radiomics models with a C-index of 0.773 (95%CI: 0.736-0.810) and 0.802 (95%CI: 0.765-0.839) for DFS and OS, respectively. CONCLUSIONS: CECT based radiomics is feasible to predict the OS and DFS for GC patients underwent chemotherapy and chemoradiation after D2 resection. The benefits of additional RT only observed in GC patients with intestinal cancer and PNI.


Assuntos
Neoplasias Gástricas , Humanos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/radioterapia , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X
11.
ACS Nano ; 17(10): 9290-9301, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37126487

RESUMO

Orthorhombic γ-CsPbI3 possesses the highest structural stability among the optically active (light-emissive) CsPbI3 perovskites. Here, we make use of a seed-assisted heteroepitaxial growth to fabricate seed/core/shell CaIx/γ-CsPbI3/CaI2 nanocrystals. Ultrasmall CaIx nanoparticles serve as seeds to template the Pb-centered octahedral arrangement which enables the formation of the γ-CsPbI3 phase and at the same time inhibit lattice strain by blocking the force transfer that otherwise leads to an octahedral twist and so improve the structural stability of the resulting nanocrystals. An outer shell composed from the same material, CaI2, isolates the formed γ-CsPbI3 nanocrystals from the environment, which also significantly improves their stability under ambient conditions. Optical and electrical studies indicate that the seed/core/shell CaIx/γ-CsPbI3/CaI2 structure possesses a shallower set of trap states as compared to cubic α-CsPbI3 nanocrystals. Light-emitting diodes utilizing these γ-CsPbI3 nanocrystals show a record high external quantum efficiency of 25.3%, high brightness of over 13600 cd/m2, and an operational lifetime of ∼14 h before reaching 50% of their initial luminance. These devices can repeatedly be illuminated over 650 times at ∼500 cd/m2 with no decline of brightness, which indicates their great commercial potential.

12.
ACS Appl Mater Interfaces ; 15(22): 26627-26636, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37220156

RESUMO

Lithium-rich layered oxides (LRLOs), with the chemical formula of xLi2MnO3·(1 - x)LiMO2, delivering higher specific discharge capacity, are potential cathode materials for lithium-ion batteries. However, the dissolution of transition metal ions and the instability of the cathode-electrolyte interphase (CEI) hinder the commercial application of LRLOs. Herein, a simple and affordable method is developed for the construction of a robust CEI layer by quenching a kind of cobalt-free LRLO, Li1.2Ni0.15Fe0.1Mn0.55O2 (denoted as NFM), in 1,1,2,2-tetrafluoroethyl-2,2,2-trifluoroethyl ether solvent. This robust CEI, with well-distributed LiF, TMFx, and partial organic component CFx, performs as a physical barrier to prevent NFM from direct contact with the electrolyte, suppresses the oxygen release, and ensures the CEI layer stability. The customized CEI with LiF and TMFx-rich phase considerably enhances the NFM cycle stability and the initial coulomb efficiency and inhibits voltage fading. This work provides a valuable strategy for designing stable interface chemistry on the cathode of lithium-ion batteries.

13.
Med Phys ; 49(12): 7779-7790, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36190117

RESUMO

BACKGROUND: Weak correlation between gamma passing rates and dose differences in target volumes and organs at risk (OARs) has been reported in several studies. Evaluation on the differences between planned dose-volume histogram (DVH) and reconstructed DVH from measurement was adopted and incorporated into patient-specific quality assurance (PSQA). However, it is difficult to develop a methodology allowing the evaluation of errors on DVHs accurately and quickly. PURPOSE: To develop a DVH-based pretreatment PSQA for volumetric modulated arc therapy (VMAT) with combined deep learning (DL) and machine learning models to overcome the limitation of conventional gamma index (GI) and improve the efficiency of DVH-based PSQA. METHODS: A DL model with a three-dimensional squeeze-and-excitation residual blocks incorporated into a modified U-net was developed to predict the measured PSQA DVHs of 208 head-and-neck (H&N) cancer patients underwent VMAT between 2018 and 2021 from two hospitals, in which 162 cases was randomly selected for training, 18 for validation, and 28 for testing. After evaluating the differences between treatment planning system (TPS) and PSQA DVHs predicted by DL model with multiple metrics, a pass or fail (PoF) classification model was developed using XGBoost algorithm. Evaluation of domain experts on dose errors between TPS and reconstructed PSQA DVHs was taken as ground truth for PoF classification model training. RESULTS: The prediction model was able to achieve a good agreement between predicted, measured, and TPS doses. Quantitative evaluation demonstrated no significant difference between predicted PSQA dose and measured dose for target and OARs, except for Dmean of PTV6900 (p = 0.001), D50 of PTV6000 (p = 0.014), D2 of PTV5400 (p = 0.009), D50 of left parotid (p = 0.015), and Dmax of left inner ear (p = 0.007). The XGBoost model achieved an area under curves, accuracy, sensitivity, and specificity of 0.89 versus 0.88, 0.89 versus 0.86, 0. 71 versus 0.71, and 0.95 versus 0.91 with measured and predicted PSQA doses, respectively. The agreement between domain experts and the classification model was 86% for 28 test cases. CONCLUSIONS: The successful prediction of PSQA doses and classification of PoF for H&N VMAT PSQA indicating that this DVH-based PSQA method is promising to overcome the limitations of GI and to improve the efficiency and accuracy of VMAT delivery.


Assuntos
Aprendizado Profundo , Neoplasias de Cabeça e Pescoço , Radioterapia de Intensidade Modulada , Humanos , Planejamento da Radioterapia Assistida por Computador/métodos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Aprendizado de Máquina , Órgãos em Risco
14.
Front Pediatr ; 10: 964147, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313892

RESUMO

Objective: The objective of this study is to introduce a novel technique of robotic-assisted laparoscopic pyeloplasty (RALP) for ureteropelvic junction obstruction (UPJO) with long proximal ureteral stricture in children. Materials and methods: Clinical information on patients who underwent a modified RALP between July 2018 and May 2019 in our center was collected retrospectively. Our surgical modifications mainly include "double-flap" tailoring of the renal pelvis and anastomosis of spatulate ureter with the double-flap. Demographic, perioperative, postoperative, and follow-up information was recorded in detail. Results: A total of 13 patients were included in the study. All the patients underwent a modified RALP without conversion to open surgery. They were followed up with a median time of 36 months. The anteroposterior diameter of the renal pelvis was 1.19 ± 0.21 at 6 months after the surgery, which was significantly lower than that on admission (3.93 ± 0.79). The split renal function of the children was also significantly improved from 0.37 ± 0.05) to 0.46 ± 0.02 at 6 months after surgery (p < 0.05). The diuretic renography revealed that all the patients have a T1/2 time less than 20 min postoperatively. The children were in good condition during the follow-up period. Conclusions: Modified RALP is an effective surgical treatment for children with UPJO with long proximal ureteral stricture. The success rate of this modification has been preliminarily confirmed.

15.
J Pediatr Surg ; 57(12): 1011-1017, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35717252

RESUMO

PURPOSE: To describe a novel modification of technique to improve efficacy of robot-assisted laparoscopic extravesical ureteral reimplantation (RALUR-EV) in infants. MATERIALS AND METHODS: Between April 2017 and July 2019, sixteen infants with primary obstructive megaureter (POM) (Age range: 4-12 months) underwent robot-assisted ureteral reimplantation were reviewed in this series. In addition to the conventional Lich-Gregoir technique, the detrusor tunnel has been extended to the mobilized anterior bladder wall to guarantee sufficient tunnel length/ureter diameter ratio and avoid ureteral angulation. All patients underwent repeated ultrasound, diuretic renal dynamic imaging and voiding cystourethrography (VCUG) perioperatively and the outcomes were documented. RESULTS: All operations were completed with robotic assisted approach without conversion. Bilateral and unilateral reimplantation were respectively performed in two and fourteen patients. The mean operative time was 115.0 ± 19.5 min and the mean blood loss was 10.0 ± 1.8 ml. There were no high-grade complications (III-IV on Clavien-Dindo classification) except for one patient. The distal ureteric diameter was reduced from pre operative 1.7 ± 0.5 to 0.6 ± 0.5 cm 6 months post operatively (p < 0.05). One child (6.3%) required the second reimplantation for stenosis. The overall operative success rate was 94.4% (17 of 18 ureters) with a mean follow-up of 15.9 ± 7.4 months with no flux detected. CONCLUSION: Our preliminary experience suggests that our modified robot-assisted laparoscopic extravesical ureteral reimplantation is feasible in infants with good results.


Assuntos
Laparoscopia , Procedimentos Cirúrgicos Robóticos , Robótica , Ureter , Obstrução Ureteral , Humanos , Criança , Lactente , Ureter/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Estudos Retrospectivos , Resultado do Tratamento , Obstrução Ureteral/diagnóstico por imagem , Obstrução Ureteral/cirurgia , Reimplante/métodos , Laparoscopia/métodos
16.
Eur J Radiol ; 154: 110393, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35679700

RESUMO

PURPOSE: To investigate the feasibility and accuracy of radiomics models based on contrast-enhanced CT (CECT) in the prediction of perineural invasion (PNI), so as to stratify high-risk recurrence and improve the management of patients with gastric cancer (GC) preoperatively. METHODS: Total of 154 GC patients underwent D2 lymph node dissection with pathologically confirmed GC and preoperative CECT from an open-label, investigator-sponsored trial (NCT01711242) were enrolled. Radiomics features were extracted from contoured images and selected using Mann-Whitney U test and the least absolute shrinkage and selection operator (LASSO) after inter-class correlation coefficient (ICC) analysis. Models based on radiomics features (R), clinical factors (C) and combined parameters (R + C) were built and evaluated using Support Vector Machine (SVM) and logistic regression to predict the PNI for patients with GC preoperatively. RESULTS: Total of 11 radiomics features were selected for final analysis, along with two clinical factors. The area under curve (AUC) of models based on R, C, and R + C with logistic regression and SVM were 0.77 vs. 0.83, 0.71 vs.0.70, 0.86 vs. 0.90, and 0.73 vs.0.80, 0.62 vs. 0.64, 0.77 vs. 0.82 in the training and testing cohorts, respectively. SVM(R + C) achieved a best AUC of 0.82(0.69-0.94) in the test cohorts with a sensitivity, specificity and accuracy of 0.63, 0.91, and 0.77, respectively. CONCLUSIONS: The performance of these models indicates that radiomics features alone or combined with clinical factors provide a feasible way to classify patients preoperatively and improve the management of patients with GC.


Assuntos
Neoplasias Gástricas , Área Sob a Curva , Humanos , Metástase Linfática , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/cirurgia , Tomografia Computadorizada por Raios X/métodos
17.
J Appl Clin Med Phys ; 23(7): e13631, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35533205

RESUMO

PURPOSE: An accurate and reliable target volume delineation is critical for the safe and successful radiotherapy. The purpose of this study is to develop new 2D and 3D automatic segmentation models based on RefineNet for clinical target volume (CTV) and organs at risk (OARs) for postoperative cervical cancer based on computed tomography (CT) images. METHODS: A 2D RefineNet and 3D RefineNetPlus3D were adapted and built to automatically segment CTVs and OARs on a total of 44 222 CT slices of 313 patients with stage I-III cervical cancer. Fully convolutional networks (FCNs), U-Net, context encoder network (CE-Net), UNet3D, and ResUNet3D were also trained and tested with randomly divided training and validation sets, respectively. The performances of these automatic segmentation models were evaluated by Dice similarity coefficient (DSC), Jaccard similarity coefficient, and average symmetric surface distance when comparing them with manual segmentations with the test data. RESULTS: The DSC for RefineNet, FCN, U-Net, CE-Net, UNet3D, ResUNet3D, and RefineNet3D were 0.82, 0.80, 0.82, 0.81, 0.80, 0.81, and 0.82 with a mean contouring time of 3.2, 3.4, 8.2, 3.9, 9.8, 11.4, and 6.4 s, respectively. The generated RefineNetPlus3D demonstrated a good performance in the automatic segmentation of bladder, small intestine, rectum, right and left femoral heads with a DSC of 0.97, 0.95, 091, 0.98, and 0.98, respectively, with a mean computation time of 6.6 s. CONCLUSIONS: The newly adapted RefineNet and developed RefineNetPlus3D were promising automatic segmentation models with accurate and clinically acceptable CTV and OARs for cervical cancer patients in postoperative radiotherapy.


Assuntos
Órgãos em Risco , Neoplasias do Colo do Útero , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Redes Neurais de Computação , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Neoplasias do Colo do Útero/cirurgia
18.
Angew Chem Int Ed Engl ; 61(30): e202202894, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35441399

RESUMO

Transition metal (e.g. Ni) ions dissolved from layered-structured Ni-rich cathodes can migrate to the anode side and accelerate the failure of lithium-ion batteries. The investigations of the impact and distribution of Ni species on the solid electrolyte interphase (SEI) on the anode are crucial to understand the failure mechanism. Herein, we used time-of-flight secondary ion mass spectroscopy (TOF-SIMS) coupled with multivariate curve resolution (MCR) analysis to intuitively characterize the distribution of Ni species in the SEI. We find that the SEI on the graphite electrode using an EC-based electrolyte exhibits a multi-stratum structure. During accelerated aging of the LiNi0.88 Co0.08 Mn0.04 O2 /graphite full cell, the dissolution of Ni aggravates significantly upon cycling. A strong correlation between the dissolved-Ni and organic species in the SEI on graphite is illustrated. The ion-exchange reaction between Ni2+ and Li+ ions in the SEI is demonstrated to be the main reason for the increase of SEI resistivity.

19.
Nanotechnology ; 33(28)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35320792

RESUMO

The potential of converting traditional biomass into low-cost HER catalysts has broad application prospects. In this paper, fungus is used as a carbon-based carrier. The bimetallic catalyst RuM-C (M = V, Mo, W, Zn, Cu) was synthesized under inert gas protection at high temperature. The order of electrocatalytic activity is RuV-C > RuZn-C > RuW-C > RuMo-C > Ru-C > RuCu-C > BF-C, which indicates that RuV-C exhibits excellent HER activity. Due to its irregular sheet structure, the specific surface area of the catalyst is increased. Impressively, it exhibits extremely high catalytic activity for HER in 1 M KOH due to favorable kinetics and excellent specific activity. Consequently, the prepared RuV-C exhibited excellent and stable HER activity compared Ru-C with a low overpotential of 65.78 mV at the current densities of 10 mA cm-2and Tafel slope of 45.26 mV dec-1. The potential only decreased by 88 mV after 24 h of continuous testing, which indicates that the catalyst has outstanding stability. This work will provide positive inspiration for the promotion of a new Ru-based biomass HER electrocatalyst.

20.
Faraday Discuss ; 233(0): 232-243, 2022 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-34874380

RESUMO

Achieving a highly efficient and durable methanol electro-oxidation catalyst in acid media is critical for the practical utilization of direct methanol fuel cells (DMFCs) at the commercial scale. Herein, we report a facile and effective one-pot strategy for the synthesis of carbon-supported PtCu alloy nanoparticles (PtCu NPs) with a Pt-rich surface, small particle size and uniform dispersion. The as-prepared PtCu NPs with the optimal alloy composition (Pt2Cu) exhibit a significantly improved electrochemical methanol oxidation reaction performance in terms of a high activity, superior CO tolerance and remarkable durability, in contrast to those of commercial Pt/C catalysts in acid media. Particularly, the Pt2Cu/C catalyst exerts a 4.5 times enhancement in the mass activity and a larger If/Ib value compared to those of commercial Pt/C (Pt/Ccomm). The enhanced catalytic activities can be ascribed to the high utilization of Pt and the high index facets of the surface. Also, the addition of Cu downshifts the d-band center of Pt and improves the CO tolerance during the methanol oxidation reaction process. This work provides an efficient strategy for designing desired Pt-based alloys for various catalytic reactions.

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