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1.
Opt Express ; 32(12): 21304-21326, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859488

RESUMO

Precious metal doping can effectively improves the catalytic performance of TiO2. In this study, pulsed laser ablation in liquid (PLAL) is employed to integrate preparation with doping and control composite nanoparticle products by adjusting the laser action time to synthesise Ag-TiO2 composite nanoparticles with high catalytic performance. The generation and evolution of Ag-TiO2 nanoparticles are investigated by analysing particle size, microscopic morphology, crystalline phase, and other characteristics. The generation and doped-morphology evolution of composite nanoparticles are simulated based on thermodynamics, and the optimisation of Ag-doped structure on the composite nanomaterials is investigated based on density functional theory. The effect of Ag-TiO2 structural properties on its performance is examined under different catalytic conditions to determine optimal degradation conditions. In this study, the effect of laser ablation time on the doped structure during PLAL is analysed, which is of further research significance in exploring the structural evolution law of laser and composite nanoparticles, multi-variate catalytic performance testing, reduction of photogenerated carrier complexation rate, and expansion of its spectral absorption range, thereby providing the basis for practical production.

2.
Angew Chem Int Ed Engl ; 59(11): 4314-4319, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-31876353

RESUMO

Non-Newtonian fluids are ubiquitous in daily life and industrial applications. Herein, we report an intelligent fluidic system integrating two distinct non-Newtonian rheological properties mediated by an autocatalytic enzyme reaction. Associative polyelectrolytes bearing a small amount of ionic and alkyl groups are engineered: by carefully balancing the charge density and the hydrophobic effect, the polymer solutions demonstrate a unique shear thickening property at low pH while shear thinning at high pH. The urea-urease clock reaction is utilized to program a feedback-induced pH change, leading to a strong upturn of the nonlinear viscoelastic properties. As long as the chemical fuel is supplied, two distinct non-Newtonian states can be achieved with a tunable lifetime span. As a proof of concept, we demonstrate how the physical energy-driven nonequilibrium properties can be manipulated by a chemical-fueled process.

3.
Macromol Rapid Commun ; 40(4): e1800691, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30565769

RESUMO

Polyion complex (PIC) hydrogels formed by charge attraction of opposite charged polymers have received unique research interest. Their conventional preparation method, with a large amount of residual salt after polymerization, requires a long-term dialysis treatment to remove the salt and toughen the gel. Here, a promising strategy for the one-step preparation of tough PIC hydrogels without dialysis after polymerization is provided. Bicarbonate and proton ions are selected as the counter ions of the cationic monomer and anionic polymers, respectively. By a CO2 -generating reaction between the counter ions, the residual salt is removed before polymerization, and thus, a PIC hydrogel with tough mechanical performance can be obtained instantly without dialysis. Due to the absence of dialysis, the tough hydrogel can be formed with a wide range of ratios for the oppositely charged polymer with distinct swelling behaviors from non-swelling to super-swelling. This tunable swelling behavior shows the possibility for shape-morphing systems from this one-step method.


Assuntos
Hidrogéis/síntese química , Polímeros/síntese química , Dióxido de Carbono/química , Hidrogéis/química , Íons/síntese química , Íons/química , Estrutura Molecular , Polímeros/química
4.
Opt Express ; 26(13): 16726-16735, 2018 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-30119495

RESUMO

The precise calibration of optical lattice depth is an important step in the experiments of ultracold atoms in optical lattices. The Raman-Nath diffraction method, as the most commonly used method of calibrating optical lattice depth, has a limited range of validity and the calibration accuracy is not high enough. Based on multiple pulses Kapitza-Dirac diffraction, we propose and demonstrate a new calibration method by measuring the fully transfer fidelity of the first diffraction order. The high sensitivity of the transfer fidelity to the lattice depth ensures the highly precision calibration of the optical lattice depth. For each lattice depth measured, the calibration uncertainty is further reduced to less than 0.6% by applying the Back-Propagation Neural Network Algorithm. The accuracy of this method is almost one order of magnitude higher than that of the Raman-Nath diffraction method, and it has a wide range of validity applicable to both shallow lattices and deep lattices.

5.
Ann Hematol ; 97(1): 141-147, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29086009

RESUMO

Pneumonitis is a rare but severe and potentially fatal adverse effect in chemotherapy of lymphoma. This study is aimed to investigate the incidence of interstitial pneumonitis in non-Hodgkin's lymphoma (NHL) patients receiving immunochemotherapy with pegylated liposomal doxorubicin and rituximab. Lymphoma patients were retrospectively reviewed, and eligible patients were included in this study. According to the chemotherapy regimens, patients were classified in four groups: combination of vincristine, cyclophosphamide, doxorubicin, and prednisone (CHOP group) with rituximab (RCHOP group) and combination of vincristine, cyclophosphamide, pegylated liposomal doxorubicin and prednisone (CDOP group) with rituximab (RCDOP group). Incidence and severity of interstitial pneumonitis were compared among the four groups. Among 757 patients reviewed, 207 patients were included in final analysis. Thirteen patients developed chemotherapy-induced interstitial pneumonitis, and the mean cycle of chemotherapy before the onset of pneumonitis was 4. Incidence rates of pneumonitis were 0, 1.8, 17.4, and 21.1% in CHOP, RCHOP, CDOP, and RCDOP groups, respectively (p < 0.001). The mean grades of pneumonitis were 0, 2, 2.5, and 3 in four groups, respectively (p < 0.001). After adjustment of confounders, chemotherapy regimens (OR 3.491, 95% CI 1.527-7.981, p = 0.003) and neutropenia in previous cycles (OR 2.186, 95% CI 1.281-3.731, p = 0.004) were independently associated with the incidence of pneumonitis. Interstitial pneumonitis should be highlighted in NHL patients who received more than 4 cycles of RCDOP chemotherapy regimen, especially in those who had grade 4 neutropenia in the previous cycles of chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Doxorrubicina/análogos & derivados , Doenças Pulmonares Intersticiais/epidemiologia , Linfoma não Hodgkin/tratamento farmacológico , Linfoma não Hodgkin/epidemiologia , Rituximab/administração & dosagem , Adulto , Idoso , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Daunorrubicina/administração & dosagem , Daunorrubicina/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Feminino , Humanos , Imunoterapia/métodos , Incidência , Doenças Pulmonares Intersticiais/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Estudos Retrospectivos , Rituximab/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos
6.
J Phys Chem A ; 122(1): 8-15, 2018 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-29220171

RESUMO

Nitrogen-rich compounds such as tetrazoles are widely used as candidates in gas-generating agents. However, the details of the differentiation of the two isomers of disubstituted tetrazoles are rarely studied, which is very important information for designing advanced materials based on tetrazoles. In this article, pairs of 2,5- and 1,5-disubstituted tetrazoles were carefully designed and prepared for study on their thermal decomposition behavior. Also, the substitution fashion of 2,5- and 1,5- and the substituents at C-5 position were found to affect the endothermic or exothermic properties. This is for the first time to the best of our knowledge that the thermal decomposition properties of different tetrazoles could be tuned by substitution ways and substitute groups, which could be used as a useful platform to design advanced materials for temperature-dependent rockets. The aza-Claisen rearrangement was proposed to understand the endothermic decomposition behavior.

7.
Support Care Cancer ; 25(4): 1183-1189, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27900546

RESUMO

PURPOSE: The assessment of quality of life (QOL) is an important part of cachexia management for cancer patients. Functional assessment of anorexia-cachexia therapy (FAACT), a specific QOL instrument for cachexia patients, has not been validated in Chinese population. The aim of this study was to validate the FAACT scale in Chinese cancer patients for its future use. METHODS: Eligible cancer patients were included in our study. Patients' demographic and clinical characteristics were collected from the electronic medical records. Patients were asked to complete the Chinese version of FAACT scale and the MD Anderson symptom inventory (MDASI), and then the reliability and validity were analyzed. RESULTS: A total of 285 patients were enrolled in our study, data of 241 patients were evaluated. Coefficients of Cronbach's alpha, test-retest and split-half analyses were all greater than 0.8, which indicated an excellent reliability for FAACT scale. In item-subscale correlation analysis and factor analysis, good construct validity for FAACT scale was found. The correlation between FAACT and MDASI interference subscale showed reasonable criterion-related validity, and for further clinical validation, the FAACT scale showed excellent discriminative validity for distinguishing patients in different cachexia status and in different performance status. CONCLUSIONS: The Chinese version of FAACT scale has good reliability and validity and is suitable for measuring QOL of cachexia patients in Chinese population.


Assuntos
Anorexia/diagnóstico , Caquexia/diagnóstico , Neoplasias/metabolismo , Adolescente , Adulto , Idoso , Anorexia/tratamento farmacológico , Povo Asiático , Caquexia/tratamento farmacológico , Registros Eletrônicos de Saúde , Análise Fatorial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Reprodutibilidade dos Testes , Inquéritos e Questionários , Adulto Jovem
8.
Eur Spine J ; 26(8): 1999-2006, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28116511

RESUMO

PURPOSE: To investigate the changes of lumbar neural foramina size during dynamic motion using positional MRI. METHODS: Two hundred and fifty neural foramina from 50 patients were analyzed. Lumbar foraminal height, width, and area parameters from L1 to S1 were evaluated for changes in extension, neutral, and flexion positions on T2 parasagittal positional MRI images, and were correlated to lumbar angular motion. One-way analysis of variance (ANOVA) and post hoc analysis were used to examine the differences between levels and positions. RESULTS: Compared to the neutral position, almost all lumbar foraminal parameters (height, width at inferior level, and area) increased in flexion and decreased in extension at all levels, except for L5-S1 foraminal width at superior and middle levels. The foraminal height and area in all lumbar segments except L5-S1 increased as the lumbar angular motion changed from extension to flexion in <40° group. The foraminal width increased significantly at L3-4 and L4-5 among all groups. CONCLUSION: Lumbar foraminal dimensions increased in flexion compared to neutral and extension positions. Lumbar angular motion contributed to the changes of foraminal height and area at most of the segments, while it affected foraminal width only at L3-4 and L4-5. This information can be useful in the understanding of patient symptoms and the correlation with the imaging studies with dynamic foraminal stenosis. Furthermore, data from our study may help with patient positioning for foraminal injections or endoscopic surgery.


Assuntos
Dor Lombar/fisiopatologia , Vértebras Lombares/fisiopatologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Feminino , Humanos , Dor Lombar/diagnóstico por imagem , Dor Lombar/patologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Amplitude de Movimento Articular , Estudos Retrospectivos , Sacro/diagnóstico por imagem , Sacro/patologia , Sacro/fisiopatologia , Adulto Jovem
9.
Surg Radiol Anat ; 39(7): 759-765, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28091734

RESUMO

PURPOSE: To investigate the change of conus medullaris termination (CMT) level in neutral, flexion and extension positions and to analyze the effects of age and gender on the CMT level. METHODS: The midline sagittal T2-weighted kinetic magnetic resonance imaging (kMRI) study of 585 patients was retrospectively reviewed to identify the level of CMT. All patients were in an upright position. A straight line perpendicular to the long axis of the cord was drawn from the tip of the cord and then subtended to the adjacent vertebra or disk space. The CMT level was labeled in relation to the upper, middle and lower segments of adjacent vertebra or disk space and assigned values from 0 to 12 [0 = upper third of T12 (T12U), and 12 = upper third of L3 (L3U)]. All parameters were collected for neutral, flexion and extension positions. RESULTS: The level of CMT had the highest incidence (17.61%) at L1 lower (L1L) in neutral position, 17.44% at L1 upper (L1U) in flexion, and 16.92% at L1 middle (L1M) in extension with no significant differences among three positions (p > 0.05) in weight-bearing status. Moreover, the level of CMT was not correlated with age (p > 0.05). In terms of gender, the level of CMT was lower in women than in men in neutral position, flexion, and extension (p < 0.05). Furthermore, when divided by age in decades, there was a significant difference between females and males in the age group 60-69 years in neutral, flexion and extension position, respectively (p < 0.05). CONCLUSIONS: The level of CMT in the neutral position was in accordance with previous cadaveric and supine-position MRI studies, and it did not change with flexion and extension. Women had lower CMT level than men, especially in the older population. This information can be very valuable when performing spinal anesthesia and spinal punctures.


Assuntos
Medula Espinal/anatomia & histologia , Adulto , Idoso , Variação Anatômica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medula Espinal/diagnóstico por imagem , Adulto Jovem
10.
Bioelectromagnetics ; 35(7): 479-90, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25145543

RESUMO

Although glucocorticoids provide benefits for inflammation or autoimmune disorders, high-dose and long-term use could cause osteonecrosis or osteoporosis as adverse effect for patients. Electromagnetic field (EMF) treatments have been clinically used for many years to promote fracture healing, but whether EMF can attenuate the deleterious effects of glucocorticoids is not clear. In this study, the effects of different concentrations of dexamethasone (DEX) on proliferation and adipogenic or osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) were detected and compared, and the effects of EMF treatment (15 Hz, 1 mT, 4 h/day) on 0.1 µM DEX-modulated BMSCs' proliferation and adipogenic or osteogenic differentiation were investigated. Higher concentrations of DEX (0.1 and 1 µM) inhibited proliferation of BMSCs but promoted expression of adipogenic-related genes, increasing the number of lipid droplets. In the early stage of differentiation, DEX restrained expression of RUNX2 and alkaline phosphatase (ALP), but amplified expression of ALP and osteopontin (OPN) in the late stage. EMF treatment of BMSCs influenced by 0.1 µM DEX inhibited the high expression of adipogenic-related genes, stimulated the expression of RUNX2, ALP, OPN, and osteocalcin, and increased the activity of ALP. EMF exposure augmented the expression of p-ERK, which DEX reduced. After using mitogen-activated protein/extracellular signal-regulated kinase (ERK) kinase (MEK)/ERK signaling pathway inhibitor, U0126, the effect of EMF was reduced. In conclusion, EMF exposure accelerates BMSCs proliferation, inhibits adipogenic differentiation, and promotes osteogenic differentiation of BMSCs modulated by DEX, and these effects are mediated at least in part by MEK/ERK signaling pathway.


Assuntos
Dexametasona/farmacologia , Campos Eletromagnéticos , Glucocorticoides/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Adipogenia/efeitos dos fármacos , Adipogenia/fisiologia , Animais , Butadienos/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/farmacologia , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/fisiologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Nitrilas/farmacologia , Osteogênese/efeitos dos fármacos , Osteogênese/fisiologia , Ratos Sprague-Dawley
11.
Neural Netw ; 178: 106436, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38908165

RESUMO

Incremental learning algorithms have been developed as an efficient solution for fast remodeling in Broad Learning Systems (BLS) without a retraining process. Even though the structure and performance of broad learning are gradually showing superiority, private data leakage in broad learning systems is still a problem that needs to be solved. Recently, Multiparty Secure Broad Learning System (MSBLS) is proposed to allow two clients to participate training. However, privacy-preserving broad learning across multiple clients has received limited attention. In this paper, we propose a Self-Balancing Incremental Broad Learning System (SIBLS) with privacy protection by considering the effect of different data sample sizes from clients, which allows multiple clients to be involved in the incremental learning. Specifically, we design a client selection strategy to select two clients in each round by reducing the gap in the number of data samples in the incremental updating process. To ensure the security under the participation of multiple clients, we introduce a mediator in the data encryption and feature mapping process. Three classical datasets are used to validate the effectiveness of our proposed SIBLS, including MNIST, Fashion and NORB datasets. Experimental results show that our proposed SIBLS can have comparable performance with MSBLS while achieving better performance than federated learning in terms of accuracy and running time.

12.
Artigo em Inglês | MEDLINE | ID: mdl-38923482

RESUMO

Time series anomaly detection is the process of identifying anomalies within time series data. The primary challenge of this task lies in the necessity for the model to comprehend the characteristics of time-independent and abnormal data patterns. In this study, a novel algorithm called adaptive memory broad learning system (AdaMemBLS) is proposed for time series anomaly detection. This algorithm leverages the rapid inference capabilities of the broad learning algorithm and the memory bank's capacity to differentiate between normal and abnormal data. Furthermore, an incremental algorithm based on multiple data augmentation techniques is introduced and applied to multiple ensemble learners, thereby enhancing the model's effectiveness in learning the characteristics of time series data. To bolster the model's anomaly detection capabilities, a more diverse ensemble approach and a discriminative anomaly score are recommended. Extensive experiments conducted on various real-world datasets demonstrate that the proposed method exhibits superior inference speed and more accurate anomaly detection compared to the existing competitors. A detailed experimental investigation is presented to elucidate the effectiveness of the proposed method and the underlying reasons for its efficacy.

13.
J Biomed Res ; 37(5): 394-400, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37750309

RESUMO

The current study aims to ascertain the anatomical feasibility of transferring the contralateral S1 ventral root (VR) to the ipsilateral L5 VR for treating unilateral spastic lower limb paralysis. Six formalin-fixed (three males and three females) cadavers were used. The VR of the contralateral S1 was transferred to the VR of the ipsilateral L5. The sural nerve was selected as a bridge between the donor and recipient nerve. The number of axons, the cross-sectional areas and the pertinent distances between the donor and recipient nerves were measured. The extradural S1 VR and L5 VR could be separated based on anatomical markers of the dorsal root ganglion. The gross distance between the S1 nerve root and L5 nerve root was 31.31 (± 3.23) mm in the six cadavers, while that on the diffusion tensor imaging was 47.51 (± 3.23) mm in 60 patients without spinal diseases, and both distances were seperately greater than that between the outlet of S1 from the spinal cord and the ganglion. The numbers of axons in the S1 VRs and L5 VRs were 13414.20 (± 2890.30) and 10613.20 (± 2135.58), respectively. The cross-sectional areas of the S1 VR and L5 VR were 1.68 (± 0.26) mm 2 and 1.08 (± 0.26) mm 2, respectively. In conclusion, transfer of the contralateral S1 VR to the ipsilateral L5 VR may be an anatomically feasible treatment option for unilateral spastic lower limb paralysis.

14.
Front Neurorobot ; 16: 827913, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35295673

RESUMO

The imbalance problem is widespread in real-world applications. When training a classifier on the imbalance datasets, the classifier is hard to learn an appropriate decision boundary, which causes unsatisfying classification performance. To deal with the imbalance problem, various ensemble algorithms are proposed. However, conventional ensemble algorithms do not consider exploring an effective feature space to further improve the performance. In addition, they treat the base classifiers equally and ignore the different contributions of each base classifier to the ensemble result. In order to address these problems, we propose a novel ensemble algorithm that combines effective data transformation and an adaptive weighted voting scheme. First, we utilize modified metric learning to obtain an effective feature space based on imbalanced data. Next, the base classifiers are assigned different weights adaptively. The experiments on multiple imbalanced datasets, including images and biomedical datasets verify the superiority of our proposed ensemble algorithm.

15.
Spine (Phila Pa 1976) ; 47(17): 1248-1252, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35867634

RESUMO

STUDY DESIGN: A total of 6 formalin-fixed cadavers were included in the cadaver feasibility study. OBJECTIVE: The aim was to ascertain the anatomical feasibility of extradural contralateral C7 ventral root transfer technique by cervical posterior. SUMMARY OF BACKGROUND DATA: Upper limb spastic hemiplegia is a common sequela after stroke. In our previous study, the authors established a method by transferring contralateral C7 dorsal and ventral roots to the corresponding C7 dorsal and ventral roots on the affected side in the cervical posterior. METHODS: In the present study, six formalin-fixed cadavers were dissected to confirm the anatomical feasibility. Experimental anastomosis in cadavers was conducted. The pertinent lengths of the extradural nerve roots were measured. The tissue structures surrounding regions between the extradural CC7 nerve roots and the vertebral artery were observed. The cervical magnetic resonance imaging scans of 60 adults were used to measure the distance between the donor and recipient nerves. RESULTS: Experimental anastomosis showed that the distance between the donor and recipient nerves was approximately 1 cm; the short segment of the sural nerve needed bridging. The distance between both exit sites of the exit of the extradural dura mater was 33.57±1.55 mm. The length of the extradural CC7 ventral root was 22.00±0.98 mm. The ventral distance (vd) and the dorsal distance (dd) in males were 23.98±1.72 mm and 30.85±2.22 mm ( P <0.05), while those in females were 23.28±1.51 mm and 30.03±2.16 mm, respectively. C7 vertebral transverse process, ligaments, and other soft tissues were observed between the vertebral artery and the extradural C7 nerve root. CONCLUSION: Under the premise of less trauma, our study shows that the extradural contralateral C7 ventral root transfer technique, in theory, yields better surgical results, including better recovery of motor function and complete preservation of sensory function. LEVEL OF EVIDENCE: 5.


Assuntos
Hemiplegia , Raízes Nervosas Espinhais , Adulto , Cadáver , Estudos de Viabilidade , Feminino , Formaldeído , Hemiplegia/cirurgia , Humanos , Masculino , Raízes Nervosas Espinhais/cirurgia , Extremidade Superior
16.
IEEE Trans Neural Netw Learn Syst ; 33(1): 75-88, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33048763

RESUMO

Graph-based methods have achieved impressive performance on semisupervised classification (SSC). Traditional graph-based methods have two main drawbacks. First, the graph is predefined before training a classifier, which does not leverage the interactions between the classifier training and similarity matrix learning. Second, when handling high-dimensional data with noisy or redundant features, the graph constructed in the original input space is actually unsuitable and may lead to poor performance. In this article, we propose an SSC method with novel graph construction (SSC-NGC), in which the similarity matrix is optimized in both label space and an additional subspace to get a better and more robust result than in original data space. Furthermore, to obtain a high-quality subspace, we learn the projection matrix of the additional subspace by preserving the local and global structure of the data. Finally, we intergrade the classifier training, the graph construction, and the subspace learning into a unified framework. With this framework, the classifier parameters, similarity matrix, and projection matrix of subspace are adaptively learned in an iterative scheme to obtain an optimal joint result. We conduct extensive comparative experiments against state-of-the-art methods over multiple real-world data sets. Experimental results demonstrate the superiority of the proposed method over other state-of-the-art algorithms.

17.
Spine (Phila Pa 1976) ; 46(20): 1363-1369, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34559748

RESUMO

STUDY DESIGN: Two fresh-frozen and six formalin-fixed cadavers were included in the study. OBJECTIVE: To ascertain whether transferring T9 or T11 ventral root (VR) to L2 VR and T10 or T12 VR to L3 VR in restoring lower limb function after spinal cord injury is anatomically feasible. SUMMARY OF BACKGROUND DATA: Lower limb paralysis impairs the quality of the life and places burden on the whole society. However, no significant improvement in this area was achieved during recent years. METHODS: In the present study, two fresh-frozen and six formalin-fixed cadavers were dissected to confirm the anatomical feasibility. A limited laminectomy was performed to expose the T9-L3 extradural nerve roots. T9 and T10 VR were anastomosed to L2 and L3 VR respectively, or T11 and T12 VR were anastomosed to L2 and L3 VR respectively. The pertinent distances between the donor and recipient nerves were measured and H&E staining was used to detect the axon number and cross-section area of each VR. RESULTS: The limited incision was performed to expose the T9-L3 nerve root. According to the anatomic landmark of dorsal root ganglion, each VR could be isolated from each extradural nerve root. The T9 or T11 VR needs sural nerve graft to be transferred to L2 VR, and T10 or T12 VR also needs a nerve bridge to connect to L3 VR. The nerve numbers of T9, T10, T11, T12, L2, and L3 VRs and the sural nerves were measured respectively. The cross-section areas of T9, T10, T11, T12, L2, and L3 VRs and sural nerves were measured respectively. CONCLUSION: Our study suggested that application of transferring T9 or T11 VR to L2 VR and T10 or T12 VR to L3 VR in restoring lower limb function is anatomically feasible.Level of Evidence: 5.


Assuntos
Traumatismos da Medula Espinal , Cadáver , Estudos de Viabilidade , Humanos , Extremidade Inferior/cirurgia , Raízes Nervosas Espinhais/cirurgia
18.
Spine (Phila Pa 1976) ; 45(11): E608-E615, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31770316

RESUMO

STUDY DESIGN: Anatomic study in nine fresh-frozen cadavers. OBJECTIVE: To confirm the anatomical feasibility of transferring the extradural ventral roots (VRs) and dorsal roots (DRs) of contralateral C7 nerves to those of the ipsilateral C7 nerves respectively through a cervical posterior approach. SUMMARY OF BACKGROUND DATA: The contralateral C7 nerve root transfer technique makes breakthrough for treating spastic limb paralysis. However, its limitations include large surgical trauma and limited indications. METHODS: Nine fresh-frozen cadavers (four females and five males) were placed prone, and the feasibility of exposing the bilateral extradural C7 nerve roots, separation of the extradural C7 VR and DR, and transfer of the VR and DR of the contralateral C7 to those of the ipsilateral C7 on the dural mater were assessed. The pertinent distances and the myelography results of each specimen were analyzed. The acetylcholinesterase (AChE) and antineurofilament 200 (NF200) double immunofluorescent staining were preformed to determine the nerve fiber properties. RESULTS: A cervical posterior midline approach was made and the laminectomy was performed to expose the bilateral extradural C7 nerve roots. After the extradural C7 VR and DR are separated, the VR and DR of the contralateral C7 have sufficient lengths to be transferred to those of the ipsilateral C7 on the dural mater. The myelography results showed that the spinal cord is not compressed after the nerve anastomosis. The AChE and NF200 double immunofluorescent staining showed the distal ends of the contralateral C7 VRs were mostly motor nerve fibers, and the distal ends of the contralateral C7 DRs were mostly sensory nerve fibers. CONCLUSION: Extradural contralateral C7 nerve root transfer in a cervical posterior approach for treating spastic limb paralysis is anatomically feasible. LEVEL OF EVIDENCE: 5.


Assuntos
Vértebras Cervicais/cirurgia , Laminectomia/métodos , Espasticidade Muscular/cirurgia , Paralisia/cirurgia , Raízes Nervosas Espinhais/cirurgia , Adulto , Idoso , Cadáver , Vértebras Cervicais/patologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espasticidade Muscular/patologia , Paralisia/patologia , Procedimentos de Cirurgia Plástica/métodos , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/cirurgia , Raízes Nervosas Espinhais/patologia
19.
IEEE Trans Neural Netw Learn Syst ; 31(4): 1387-1400, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31265410

RESUMO

The class imbalance problem has become a leading challenge. Although conventional imbalance learning methods are proposed to tackle this problem, they have some limitations: 1) undersampling methods suffer from losing important information and 2) cost-sensitive methods are sensitive to outliers and noise. To address these issues, we propose a hybrid optimal ensemble classifier framework that combines density-based undersampling and cost-effective methods through exploring state-of-the-art solutions using multi-objective optimization algorithm. Specifically, we first develop a density-based undersampling method to select informative samples from the original training data with probability-based data transformation, which enables to obtain multiple subsets following a balanced distribution across classes. Second, we exploit the cost-sensitive classification method to address the incompleteness of information problem via modifying weights of misclassified minority samples rather than the majority ones. Finally, we introduce a multi-objective optimization procedure and utilize connections between samples to self-modify the classification result using an ensemble classifier framework. Extensive comparative experiments conducted on real-world data sets demonstrate that our method outperforms the majority of imbalance and ensemble classification approaches.

20.
J Orthop Surg Res ; 15(1): 574, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33256851

RESUMO

BACKGROUND: Pedicle screw fixation is a well-established technique for thoracolumbar fracture. A large number of studies have shown that the bending angle of the connecting rod has a significant correlation with the postoperative spinal stability. However, no studies have confirmed an objective indicator to guide the bending angle of the connecting rod during the operation. Our study aims to define a sagittal Cobb* angle to guide the bending angle of the connecting rod during surgery. METHODS: The frontal and lateral X-ray films in 150 cases of normal thoracolumbar spine were included to measure the normal spinal sagittal Cobb* angle in each segment. The patients who underwent single segment thoracolumbar fractures and pedicle screw internal fixation surgery were included. The radiological parameters included lumbar lordosis (LL), thoracic kyphosis (TK), pelvic tilt (PT), pelvic incidence (PI), sagittal vertical axis (SVA), and sacral slope (SS) were measured. The incidence of adjacent segment degeneration (ASD) 2 years after surgery was measured. RESULTS: The average values of normal sagittal Cobb* angle in each segment were - 5.196 ± 3.318° (T12), 2.279 ± 3.324° (L1), 7.222 ± 2.798° (L2), and 12.417 ± 11.962° (L3), respectively. The LL in the three groups was 35.20 ± 9.12°, 46.26 ± 9.68°, and 54.24 ± 15.31°, respectively. Compared with the normal group, there were significant differences in group A and group C, respectively (p < 0.05). The results were similar in the parameters of TL, PT, and SS. The incidences of SVA > 50 mm in group A, group B, and group C were 23.33%, 12.50%, and 19.23%, respectively. The parameter of PI in three groups was 41.36 ± 12.69, 44.53 ± 15.27, and 43.38 ± 9.85°, respectively. The incidences of ASD in group A, group B, and group C 2 years after surgery were 21.67%, 13.75%, and 17.95%, respectively. CONCLUSIONS: The study confirmed that the sagittal Cobb* angle can be used as a reference angle for bending rods. When the bending angle of the connecting rod is 4 to 8° greater than the corresponding segment sagittal Cobb* angle, the patient's spinal sagittal stability is the best 2 years after the operation.


Assuntos
Fixação Interna de Fraturas/métodos , Vértebras Lombares/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/cirurgia , Feminino , Seguimentos , Fixação Interna de Fraturas/instrumentação , Humanos , Degeneração do Disco Intervertebral/diagnóstico por imagem , Cifose/diagnóstico por imagem , Lordose/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Parafusos Pediculares , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Fatores de Tempo
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