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1.
Artigo em Inglês | MEDLINE | ID: mdl-38814574

RESUMO

Phosphorylation, the most extensive and pleiotropic form of protein post-translation modification, is central to cellular signal transduction. Throughout the extensive co-evolution of plant hosts and viruses, modifications to phosphorylation have served multiple purposes. Such modifications highlight the evolutionary trajectories of viruses and their hosts, with pivotal roles in regulation and refinement of host-virus interactions. In plant hosts, protein phosphorylation orchestrates immune responses, enhancing the activities of defense-related proteins such as kinases and transcription factors, thereby strengthening pathogen resistance in plants. Moreover, phosphorylation influences the interactions between host and viral proteins, altering viral spread and replication within host plants. In the context of plant viruses, protein phosphorylation controls key aspects of the infection cycle, including viral protein functionality and the interplay between viruses and host plant cells, leading to effects on viral accumulation and dissemination within plant tissues. Explorations of the nuances of protein phosphorylation in plant hosts and their interactions with viruses are particularly important. This review provides a systematic summary of the biological roles of the proteins of plant viruses carrying diverse genomes in regulating infection and host responses through changes in the phosphorylation status.

2.
Opt Express ; 31(3): 4238-4252, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36785397

RESUMO

Femtosecond lasers can be used to create many functional devices in silica optical fibers with high designability. In this work, a femtosecond laser-induced high scattering fiber (HSF) with randomly distributed high scattering centers is used to effectively compress the linewidth of a fiber laser for the first time. A dual-wavelength, single-longitudinal-mode (SLM) erbium-doped fiber laser (EDFL) is constructed for the demonstration, which is capable of switching among two single-wavelength operations and one dual-wavelength operation. We find that the delayed self-heterodyne beating linewidth of the laser can be reduced from >1 kHz to <150 Hz when the length of the HSF in the laser cavity increases from 0 m to 20 m. We also find that the intrinsic Lorentzian linewidth of the laser can be compressed to several Hz using the HSF. The efficiency and effectiveness of linewidth reduction are also validated for the case that the laser operates in simultaneous dual-wavelength lasing mode. In addition to the linewidth compression, the EDFL shows outstanding overall performance after the HSF is incorporated. In particular, the optical spectrum and SLM lasing state are stable over long periods of time. The relative intensity noise is as low as <-150 dB/Hz@>3 MHz, which is very close to the shot noise limit. The optical signal-to-noise ratios of >85 dB for single-wavelength operation and >83 dB for dual-wavelength operation are unprecedented over numerous SLM fiber lasers reported previously. This novel method for laser linewidth reduction is applicable across gain-medium-type fiber lasers, which enables low-cost, high-performance, ultra-narrow linewidth fiber laser sources for many applications.

3.
J Cell Biochem ; 120(5): 7516-7526, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30417553

RESUMO

Glioma is a common primary brain tumor with high mortality rate and poor prognosis. Long noncoding RNA maternally expressed gene 3 (MEG3) is a tumor suppressor in diverse cancer types. However, the role of MEG3 in glioma remains unclear. We aimed to explore the effects of MEG3 on U251 cells as well as the underlying mechanisms. U251 cells were stably transfected with different recombined plasmids to overexpress or silence MEG3. Effects of aberrantly expressed MEG3 on cell viability, migration, apoptosis, expressions of apoptosis-associated and autophagy-associated proteins, and phosphorylated levels of key kinases in the PI3K/AKT/mTOR pathway were all evaluated. Then, messenger RNA (mRNA) and protein expression of Sirt7 in cells abnormally expressing MEG3 were estimated. In addition, effects of abnormally expressed MEG3 and Sirt7 on U251 cells were determined to reveal the underlying mechanism of MEG3-associated modulation. Cell viability and migration were significantly reduced by MEG3 overexpression whereas cell apoptosis as well as Bax and cleaved caspase-3/-9 proteins were obviously induced. Beclin-1 and LC3-II/LC3-I were upregulated and p62 was downregulated in MEG3 overexpressed cells. In addition, the autophagy pharmacological inhibitor (3-methyladenine, 3-MA) affected the effect of MEG3 overexpression on cell proliferation. Furthermore, the phosphorylated levels of key kinases in the PI3K/AKT/mTOR pathway were all reduced by MEG3 overexpression. Sirt7 was positively regulated by MEG3 expression, and effects of MEG3 overexpression on U251 cells were ameliorated by Sirt7 silence. MEG3 suppressed cell proliferation and migration but promoted autophagy in U251 cells through positively regulating Sirt7, involving in the inhibition of the PI3K/AKT/mTOR pathway.

4.
Cell Physiol Biochem ; 49(5): 2012-2021, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30244244

RESUMO

BACKGROUND/AIMS: Ligustrazine (LSZ) has been identified as an antitumor agent against some types of cancers. Nevertheless, its ability to inhibit growth, migration and invasion of medulloblastoma cells is still unclear. This study aimed to explore the effect of LSZ on Daoy cells. METHODS: The effects of LSZ on viability, proliferation, apoptosis, migration, and invasion of Daoy cells were analyzed by CCK-8, BrdU, flow cytometry and Transwell assays, respectively. The effect of LSZ on miR-211 expression was analyzed by qRT-PCR. miR-211 inhibitor transfection was performed to suppress miR-211 expression. The effects of LSZ on apoptosis-related factors, MMP-2, MMP-9, and Vimentin (Vim), as well as main factors of PI3K/AKT and mTOR pathways were analyzed by Western blot. RESULTS: LSZ inhibited viability but promoted apoptosis of Daoy cells. Additionally, the proliferative, migratory and invasive abilities of Daoy cells were decreased by LSZ. Meanwhile, LSZ promoted the activations of Caspase-3 and Caspase-9, increased Bax level, decreased Bcl-2 level, as well as inhibited the expressions of MMP-2, MMP-9 and Vim. Additionally, we found that LSZ enhanced miR-211 expression and exerted its anti-medulloblastoma effect by up-regulation of miR-211. Furthermore, LSZ inhibited PI3K/AKT and mTOR signaling pathways by up-regulating miR-211. CONCLUSION: LSZ suppressed medulloblastoma Daoy cells by up-regulating miR-211 and further modulating the activations of PI3K/AKT and mTOR signaling pathways.


Assuntos
Proliferação de Células/efeitos dos fármacos , MicroRNAs/metabolismo , Pirazinas/farmacologia , Regulação para Cima/efeitos dos fármacos , Vasodilatadores/farmacologia , Antagomirs/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Meduloblastoma/metabolismo , Meduloblastoma/patologia , MicroRNAs/antagonistas & inibidores , MicroRNAs/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazinas/química , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Vasodilatadores/química
5.
J Stroke Cerebrovasc Dis ; 24(1): e5-9, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25270634

RESUMO

Growing basilar dissecting aneurysm is a scarce but increasingly recognized entity, accounting for a significant risk of death and disability. Controversy exists regarding the optimal management. A 61-year-old man presented with dysarthria and left hemiparesis attributable to a basilar trunk dissecting aneurysm. Antiplatelet therapy was instituted, and the patient's clinical condition markedly improved. However, he developed severe headache, dysarthria, and left hemiparesis 35 days later. Angiography revealed significant enlargement of the aneurysm, and stent-assisted coiling was then uneventfully performed. The patient remained clinically stable with only mild left-sided hemiparesis at the 2-year clinical follow-up.


Assuntos
Dissecção Aórtica/cirurgia , Disartria/cirurgia , Aneurisma Intracraniano/cirurgia , Paresia/cirurgia , Stents , Dissecção Aórtica/complicações , Disartria/etiologia , Procedimentos Endovasculares , Humanos , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Paresia/etiologia , Resultado do Tratamento
6.
Artigo em Inglês | MEDLINE | ID: mdl-38781065

RESUMO

Active learning seeks to achieve strong performance with fewer training samples. It does this by iteratively asking an oracle to label newly selected samples in a human-in-the-loop manner. This technique has gained increasing popularity due to its broad applicability, yet its survey papers, especially for deep active learning (DAL), remain scarce. Therefore, we conduct an advanced and comprehensive survey on DAL. We first introduce reviewed paper collection and filtering. Second, we formally define the DAL task and summarize the most influential baselines and widely used datasets. Third, we systematically provide a taxonomy of DAL methods from five perspectives, including annotation types, query strategies, deep model architectures, learning paradigms, and training processes, and objectively analyze their strengths and weaknesses. Then, we comprehensively summarize the main applications of DAL in natural language processing (NLP), computer vision (CV), data mining (DM), and so on. Finally, we discuss challenges and perspectives after a detailed analysis of current studies. This work aims to serve as a useful and quick guide for researchers in overcoming difficulties in DAL. We hope that this survey will spur further progress in this burgeoning field.

7.
J Vis Exp ; (207)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38829141

RESUMO

Oncoplastic breast surgery, with its focus on improving cosmetic outcomes while maintaining oncological safety, has fundamentally transformed the landscape of breast cancer surgical treatment, giving rise to an array of techniques for breast reconstruction. Nipple-sparing mastectomy (NSM) with immediate implant-based breast reconstruction (IBBR) has emerged as a cornerstone in managing early breast cancer. Aligned with the principles of minimally invasive surgery, recent years have witnessed the widespread integration of endoscopic approaches in breast surgery, encompassing procedures like endoscopic breast-conserving surgery (E-BCS) and endoscopic nipple-sparing mastectomy (E-NSM), among others. Capitalizing on the advantages of inconspicuous and shorter incisions, improved visibility, and the avoidance of radiation therapy, the popularity of E-NSM with IBBR is on the rise. However, conventional E-NSM with IBBR often requires two or more incisions, which can result in suboptimal cosmetic outcomes and even prosthesis loss.This paper presents a comprehensive account of the intricate surgical procedures involved in endoscopic bilateral nipple-sparing mastectomy with immediate pre-pectoral implant-based breast reconstruction. The insights shared are drawn from the collective experience of our institution. Notable benefits associated with the described surgical approach encompass enhanced cosmetic outcomes, improved postoperative quality of life, and enhanced physiological functions attributable to the application of pre-pectoral implant-based breast reconstruction through a single incision.


Assuntos
Neoplasias da Mama , Endoscopia , Mamilos , Humanos , Feminino , Endoscopia/métodos , Neoplasias da Mama/cirurgia , Mamilos/cirurgia , Mamoplastia/métodos , Mamoplastia/instrumentação , Mastectomia/métodos , Axila/cirurgia , Implantes de Mama
8.
Comput Methods Programs Biomed ; 244: 107995, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38157826

RESUMO

BACKGROUND AND OBJECTIVE: With the urgent demands for rapid and precise localization of pulmonary nodules in procedures such as transthoracic puncture biopsy and thoracoscopic surgery, many surgical navigation and robotic systems are applied in the clinical practice of thoracic operation. However, current available positioning methods have certain limitations, including high radiation exposure, large errors from respiratory, complicated and time-consuming procedures, etc. METHODS: To address these issues, a preoperative computed tomography (CT) image-guided robotic system for transthoracic puncture was proposed in this study. Firstly, an algorithm for puncture path planning based on constraints from clinical knowledge was developed. This algorithm enables the calculation of Pareto optimal solutions for multiple clinical targets concerning puncture angle, puncture length, and distance from hazardous areas. Secondly, to eradicate intraoperative radiation exposure, a fast registration method based on preoperative CT and gated respiration compensation was proposed. The registration process could be completed by the direct selection of points on the skin near the sternum using a hand-held probe. Gating detection and joint optimization algorithms are then performed on the collected point cloud data to compensate for errors from respiratory motion. Thirdly, to enhance accuracy and intraoperative safety, the puncture guide was utilized as an end effector to restrict the movement of the optically tracked needle, then risky actions with patient contact would be strictly limited. RESULTS: The proposed system was evaluated through phantom experiments on our custom-designed simulation test platform for patient respiratory motion to assess its accuracy and feasibility. The results demonstrated an average target point error (TPE) of 2.46 ± 0.68 mm and an angle error (AE) of 1.49 ± 0.45° for the robotic system. CONCLUSIONS: In conclusion, our proposed system ensures accuracy, surgical efficiency, and safety while also reducing needle insertions and radiation exposure in transthoracic puncture procedures, thus offering substantial potential for clinical application.


Assuntos
Procedimentos Cirúrgicos Robóticos , Cirurgia Assistida por Computador , Humanos , Procedimentos Cirúrgicos Robóticos/métodos , Biópsia por Agulha , Cirurgia Assistida por Computador/métodos , Punções , Algoritmos
9.
Acta Neurochir (Wien) ; 155(2): 271-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23108561

RESUMO

We herein coin the term "remote peritentorial hemorrhage (RPTH)" and present three cases with "RPTH" after supratentorial aneurysmal surgeries, including two with remote cerebellar hemorrhage (RCH) and one with remote temporobasal hemorrhage. The RCH may result from rupture of the superior cerebellar veins due to excessive cerebrospinal fluid (CSF) loss. The mechanism behind the remote temporobasal hemorrhage may be similar to that of RCH. It can be explained by tearing of the temporobasal veins as a result of brain shift owing to intracranial hypotension stemming from intensive loss of CSF. As far as we know, this is the first report of such a bleeding pattern of probable venous origin. The results of this study could shed light on the "RPTH" physiopathology.


Assuntos
Aneurisma Roto/cirurgia , Cerebelo , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/etiologia , Craniotomia/efeitos adversos , Aneurisma Intracraniano/cirurgia , Idoso , Aneurisma Roto/diagnóstico , Aneurisma Roto/fisiopatologia , Hemorragia Cerebral/terapia , Feminino , Humanos , Aneurisma Intracraniano/diagnóstico , Aneurisma Intracraniano/fisiopatologia , Masculino , Pessoa de Meia-Idade
10.
Cell Rep ; 42(7): 112673, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37342911

RESUMO

The neural code of faces has been intensively studied in the macaque face patch system. Although the majority of previous studies used complete faces as stimuli, faces are often seen partially in daily life. Here, we investigated how face-selective cells represent two types of incomplete faces: face fragments and occluded faces, with the location of the fragment/occluder and the facial features systematically varied. Contrary to popular belief, we found that the preferred face regions identified with two stimulus types are dissociated in many face cells. This dissociation can be explained by the nonlinear integration of information from different face parts and is closely related to a curved representation of face completeness in the state space, which allows a clear discrimination between different stimulus types. Furthermore, identity-related facial features are represented in a subspace orthogonal to the nonlinear dimension of face completeness, supporting a condition-general code of facial identity.


Assuntos
Face , Macaca , Animais , Estimulação Luminosa/métodos , Imageamento por Ressonância Magnética/métodos
11.
IEEE Trans Cybern ; 53(3): 1653-1666, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34495863

RESUMO

Temporal networks are ubiquitous in nature and society, and tracking the dynamics of networks is fundamental for investigating the mechanisms of systems. Dynamic communities in temporal networks simultaneously reflect the topology of the current snapshot (clustering accuracy) and historical ones (clustering drift). Current algorithms are criticized for their inability to characterize the dynamics of networks at the vertex level, independence of feature extraction and clustering, and high time complexity. In this study, we solve these problems by proposing a novel joint learning model for dynamic community detection in temporal networks (also known as jLMDC) via joining feature extraction and clustering. This model is formulated as a constrained optimization problem. Vertices are classified into dynamic and static groups by exploring the topological structure of temporal networks to fully exploit their dynamics at each time step. Then, jLMDC updates the features of dynamic vertices by preserving features of static ones during optimization. The advantage of jLMDC is that features are extracted under the guidance of clustering, promoting performance, and saving the running time of the algorithm. Finally, we extend jLMDC to detect the overlapping dynamic community in temporal networks. The experimental results on 11 temporal networks demonstrate that jLMDC improves accuracy up to 8.23% and saves 24.89% of running time on average compared to state-of-the-art methods.

12.
Gene ; 864: 147291, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36813061

RESUMO

The transient receptor potential mucolipin (TRPML) subfamily in mammalian has three members, namely TRPML1, TRPML2, and TRPML3, who play key roles in regulating intracellular Ca2+ homeostasis, endosomal pH, membrane trafficking and autophagy. Previous studies had shown that three TRPMLs are closely related to the occurrence of pathogen invasion and immune regulation in some immune tissues or cells, but the relationship between TRPMLs expression and pathogen invasion in lung tissue or cell remains elusive. Here, we investigated the expression distribution of three TRPML channels in mouse different tissues by qRT-PCR, and then found that all three TRPMLs were highly expressed in the mouse lung tissue, as well as mouse spleen and kidney tissues. The expression of TRPML1 or TRPML3 in all three mouse tissues had a significant down-regulation after the treatment of Salmonella or LPS, but TRPML2 expression showed a remarkable increase. Consistently, TRPML1 or TRPML3 but not TRPML2 in A549 cells also displayed a decreased expression induced by LPS stimulation, which shared a similar regulation pattern in the mouse lung tissue. Furthermore, the treatment of the TRPML1 or TRPML3 specific activator induced a dose-dependent up-regulation of inflammatory factors IL-1ß, IL-6 and TNFα, suggesting that TRPML1 and TRPML3 are likely to play an important role in immune and inflammatory regulation. Together, our study identified the gene expression of TRPMLs induced by pathogen stimulation in vivo and in vitro, which may provide novel targets for innate immunity or pathogen regulation.


Assuntos
Canais de Potencial de Receptor Transitório , Animais , Camundongos , Canais de Potencial de Receptor Transitório/genética , Canais de Potencial de Receptor Transitório/metabolismo , Lipopolissacarídeos/metabolismo , Homeostase , Expressão Gênica , Lisossomos , Mamíferos/genética
13.
IEEE/ACM Trans Comput Biol Bioinform ; 19(4): 2219-2230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33780342

RESUMO

Tracking the dynamic modules (modules change over time) during cancer progression is essential for studying cancer pathogenesis, diagnosis, and therapy. However, current algorithms only focus on detecting dynamic modules from temporal cancer networks without integrating the heterogeneous genomic data, thereby resulting in undesirable performance. To attack this issue, we propose a novel algorithm (aka TANMF) to detect dynamic modules in cancer temporal attributed networks, which integrates the temporal networks and gene attributes. To obtain the dynamic modules, the temporality and gene attributed are incorporated into an overall objective function, which transforms the dynamic module detection into an optimization problem. TANMF jointly decomposes the snapshots at two subsequent time steps to obtain the latent features of dynamic modules, where the attributes are fused via regulations. Furthermore, the L1 constraint is imposed to improve the robustness. Experimental results demonstrate that TANMF is more accurate than state-of-the-art methods in terms of accuracy. By applying TANMF to breast cancer data, the obtained dynamic modules are more enriched by the known pathways and associated with patients' survival time. The proposed model and algorithm provide an effective way for the integrative analysis of heterogeneous omics.


Assuntos
Neoplasias da Mama , Redes Reguladoras de Genes , Algoritmos , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Feminino , Redes Reguladoras de Genes/genética , Genômica , Humanos
14.
IEEE Trans Biomed Eng ; 69(8): 2593-2603, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35157575

RESUMO

OBJECTIVE: Cervical pedicle screw (CPS) placement surgery remains technically demanding due to the complicated anatomy with neurovascular structures. State-of-the-art surgical navigation or robotic systems still suffer from the problem of hand-eye coordination and soft tissue deformation. In this study, we aim at tracking the intraoperative soft tissue deformation and constructing a virtual-physical fusion surgical scene, and integrating them into the robotic system for CPS placement surgery. METHODS: Firstly, we propose a real-time deformation computation method based on the prior shape model and intraoperative partial information acquired from ultrasound images. According to the generated posterior shape, the structure representation of deformed target tissue gets updated continuously. Secondly, a hand tremble compensation method is proposed to improve the accuracy and robustness of the virtual-physical calibration procedure, and a mixed reality based surgical scene is further constructed for CPS placement surgery. Thirdly, we integrate the soft tissue deformation method and virtual-physical fusion method into our previously proposed surgical robotic system, and the surgical workflow for CPS placement surgery is introduced. RESULTS: We conducted phantom and animal experiments to evaluate the feasibility and accuracy of the proposed system. Our system yielded a mean surface distance error of 1.52 ± 0.43 mm for soft tissue deformation computing, and an average distance deviation of 1.04 ± 0.27 mm for CPS placement. CONCLUSION: Results demonstrate that our system involves tremendous clinical application potential. SIGNIFICANCE: Our proposed system promotes the efficiency and safety of the CPS placement surgery.


Assuntos
Realidade Aumentada , Parafusos Pediculares , Procedimentos Cirúrgicos Robóticos , Fusão Vertebral , Cirurgia Assistida por Computador , Animais , Vértebras Cervicais/diagnóstico por imagem , Vértebras Cervicais/cirurgia , Fusão Vertebral/métodos , Cirurgia Assistida por Computador/métodos
15.
Math Biosci Eng ; 19(9): 9505-9519, 2022 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-35942770

RESUMO

This paper proposes an anti-rotation template matching method based on a portion of the whole pixels. To solve the problem that the speed of the original template matching method based on NCC (Normalized cross correlation) is too slow for the rotated image, a template matching method based on Sub-NCC is proposed, which improves the anti-jamming ability of the algorithm. At the same time, in order to improve the matching speed, the rotation invariant edge points are selected from the rotation invariant pixels, and the selected points are used for rough matching to quickly screen out the unmatched areas. The theoretical analysis and experimental results show that the accuracy of this method is more than 95%. For the search map at any angle with the resolution at the level of 300,000 pixel, after selecting the appropriate pyramid series and threshold, the matching time can be controlled to within 0.1 s.


Assuntos
Interpretação de Imagem Assistida por Computador , Reconhecimento Automatizado de Padrão , Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos
16.
ACS Omega ; 7(9): 8036-8045, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35284746

RESUMO

Coalbed methane is a type of high-quality clean energy. The development of coalbed methane helps protect the living environment of humans and solves the safety problems in coal mining. However, a large amount of pulverized coal is generated after coalbed methane fracturing, which reduces the production of coalbed methane. Reduction of pulverized coal generation and prevention of pulverized coal migration are important for the development of coalbed methane. This study innovatively mixed calcium sulfoaluminate particles and sand to create a new fracturing proppant. The new proppant was carried by the fracturing fluid into the formation cracks and cured to form a permeable cement stone with a certain compressive strength and permeability at formation temperature and pressure. The permeability and compressive strength of the permeable cement stone were measured at different curing temperatures. Results showed that when the compressive strength of the permeable cement stone was 5.46 MPa, the gas and water permeabilities could reach 2.06 and 0.57 D, respectively. The pore diameter distribution was measured with the semi-permeable diaphragm method. The distribution curve was bimodal, and the range of the variation in pore size was 0.6-300 µm. Blocked pulverized coal size was determined using the seepage theory of particles in porous media and verified through a pulverized coal control experiment. Pulverized coal with a diameter larger than 7.67 µm was blocked by the permeable cement stone. The efficiency of the permeable cement stone in controlling pulverized coal could reach 96%. This study proved that calcium sulfoaluminate cementitious proppants can fix pulverized coal and prevent its migration. It also provided the compressive strength of propping fractures and the high permeability needed for drainage under formation conditions.

17.
Comput Biol Med ; 133: 104402, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33895460

RESUMO

BACKGROUND AND OBJECTIVE: The distal interlocking of intramedullary nail remains a technically demanding procedure. Existing augmented reality based solutions still suffer from hand-eye coordination problem, prolonged operation time, and inadequate resolution. In this study, an augmented reality based navigation system for distal interlocking of intramedullary nail is developed using Microsoft HoloLens 2, the state-of-the-art optical see-through head-mounted display. METHODS: A customized registration cube is designed to assist surgeons with better depth perception when performing registration procedures. During drilling, surgeons can obtain accurate and in-situ visualization of intramedullary nail and drilling path, and dynamic navigation is enabled. An intraoperative warning system is proposed to provide intuitive feedback of real-time deviations and electromagnetic disturbances. RESULTS: The preclinical phantom experiment showed that the reprojection errors along the X, Y, and Z axes were 1.55 ± 0.27 mm, 1.71 ± 0.40 mm, and 2.84 ± 0.78 mm, respectively. The end-to-end evaluation method indicated the distance error was 1.61 ± 0.44 mm, and the 3D angle error was 1.46 ± 0.46°. A cadaver experiment was also conducted to evaluate the feasibility of the system. CONCLUSION: Our system has potential advantages over the 2D-screen based navigation system and the pointing device based navigation system in terms of accuracy and time consumption, and has tremendous application prospects.


Assuntos
Realidade Aumentada , Fixação Intramedular de Fraturas , Cirurgia Assistida por Computador , Fixadores Internos , Imagens de Fantasmas
18.
Int J Med Robot ; 17(3): e2243, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33580624

RESUMO

BACKGROUND: The patient-specific templates for osteotomy often have complex surface features. Using current commercial software to design such templates is quite complicated, tedious and unrepeatable. AIMS: In this study, a novel surgical planning system for oral and maxillofacial surgery named EasyTemplate is developed, aiming to help doctors shorten the modelling time and assure the reliability in template design. MATERIALS & METHODS: In the simplified design process of an osteotomy guide, the main template can be formed efficiently using a surface offsetting algorithm, which is based on isosurface extraction and oriented bounding box. Thereafter, the cutting grooves can be generated automatically. RESULTS: A complicated surgical guide could be built accurately in about 10 min. Clinical orthognathic cases were conducted successfully using osteotomy and repositioning templates designed by EasyTemplate. DISCUSSION: Compared with commercially available softwares, higher efficiency and simpler design process were achieved, moreover, the time cost is one-third or even less. CONCLUSION: EasyTemplate can be a useful alternative to traditional softwares. This software allows the auto-generation algorithm which helps avoid a tedious modeling process while providing basic shapes for designers.


Assuntos
Cirurgia Assistida por Computador , Cirurgia Bucal , Desenho Assistido por Computador , Computadores , Humanos , Imageamento Tridimensional , Impressão Tridimensional , Reprodutibilidade dos Testes , Software
20.
J Hazard Mater ; 384: 121225, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585285

RESUMO

Oil-based drill cuttings (OBDC) is a characteristic hazardous waste that is generated in oil and gas exploration. In this study, two typical OBDCs from shale gas fields were treated in a continuous supercritical water oxidation (SCWO) for the first time. Because both heat value and ash content (AC) in the OBDCs were well beyond the capacity of continuous operation, municipal sewage sludge (MSS) was innovatively adapted as the diluent. A mixed sludge with OBDC addition levels of 10%, 20%, and 30% was tested using a novel SCWO reactor. Mean residence times of reactants in different reaction zones were specifically calculated. Results indicated the organic carbon removal efficiency could reach up to 98.44%. Eight detected heavy metals were found to be almost completely removed into solid products, and the concentrations in liquid products were all below the discharge limits. It was also found that the SCWO reactor exhibited good anti-plugging and anti-corrosion performance. The AC in the feedstock was up to 28.58%. To the best of our knowledge, this has, hitherto, not been achieved in a continuous SCWO operation. This study provides a new approach for harmlessly and completely degrading OBDC, and is also helpful for the industrialization of SCWO technology.


Assuntos
Resíduos Industriais , Indústria de Petróleo e Gás , Esgotos , Eliminação de Resíduos Líquidos/métodos , Metais Pesados/análise , Oxirredução , Petróleo , Temperatura , Água/química , Poluentes Químicos da Água/análise
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