Glaucoma disease causes irreversible damage to the optical nerve and it has the potential to cause permanent loss of vision.Glaucoma ranks as the second most prevalent cause of permanent blindness.Traditional glaucoma...Glaucoma disease causes irreversible damage to the optical nerve and it has the potential to cause permanent loss of vision.Glaucoma ranks as the second most prevalent cause of permanent blindness.Traditional glaucoma diagnosis requires a highly experienced specialist,costly equipment,and a lengthy wait time.For automatic glaucoma detection,state-of-the-art glaucoma detection methods include a segmentation-based method to calculate the cup-to-disc ratio.Other methods include multi-label segmentation networks and learning-based methods and rely on hand-crafted features.Localizing the optic disc(OD)is one of the key features in retinal images for detecting retinal diseases,especially for glaucoma disease detection.The approach presented in this study is based on deep classifiers for OD segmentation and glaucoma detection.First,the optic disc detection process is based on object detection using a Mask Region-Based Convolutional Neural Network(Mask-RCNN).The OD detection task was validated using the Dice score,intersection over union,and accuracy metrics.The OD region is then fed into the second stage for glaucoma detection.Therefore,considering only the OD area for glaucoma detection will reduce the number of classification artifacts by limiting the assessment to the optic disc area.For this task,VGG-16(Visual Geometry Group),Resnet-18(Residual Network),and Inception-v3 were pre-trained and fine-tuned.We also used the Support Vector Machine Classifier.The feature-based method uses region content features obtained by Histogram of Oriented Gradients(HOG)and Gabor Filters.The final decision is based on weighted fusion.A comparison of the obtained results from all classification approaches is provided.Classification metrics including accuracy and ROC curve are compared for each classification method.The novelty of this research project is the integration of automatic OD detection and glaucoma diagnosis in a global method.Moreover,the fusion-based decision system uses the glaucoma detection result obtained using several convolutional deep neural networks and the support vector machine classifier.These classification methods contribute to producing robust classification results.This method was evaluated using well-known retinal images available for research work and a combined dataset including retinal images with and without pathology.The performance of the models was tested on two public datasets and a combined dataset and was compared to similar research.The research findings show the potential of this methodology in the early detection of glaucoma,which will reduce diagnosis time and increase detection efficiency.The glaucoma assessment achieves about 98%accuracy in the classification rate,which is close to and even higher than that of state-of-the-art methods.The designed detection model may be used in telemedicine,healthcare,and computer-aided diagnosis systems.展开更多
The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake discs.In this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigat...The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake discs.In this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical properties.Compacted graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of ferrite.The peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction tests.The morphology of thermal cracks and 3D profiles of the worn surfaces were also discussed.It is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue resistance.Oxidization of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal cracks.Despite the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.展开更多
Introduction: Congenital optic disc anomalies in children refer to structural variations of the optic nerve head present from birth. These deformations involve the size, shape, color, and vessels of the optic disc. Al...Introduction: Congenital optic disc anomalies in children refer to structural variations of the optic nerve head present from birth. These deformations involve the size, shape, color, and vessels of the optic disc. Although often asymptomatic, these anomalies can impact the visual development of the child, underscoring the importance of a thorough fundus examination for early detection and appropriate medical follow-up. We present two cases of congenital optic disc anomalies in children, illustrating the diagnostic challenges and complexity of their management. Case 1: A 3-year-old girl presented with a white spot in her left eye present since birth. Uncorrected distance visual acuity was 2/10 in the right eye, while she could perceive hand movements at 2 meters with the left eye. Normal examination in the right eye showed leukocoria, microphthalmia, and a white mass at the center of the optic disc on fundus examination in the left eye. Ocular imaging, including ultrasound and optical coherence tomography (OCT), confirmed the diagnosis of persistent hyperplastic primary vitreous (PHPV) in its mixed form in the left eye. Management included prescribing full optical correction and functional rehabilitation, without resorting to surgery. The course was marked by persistent amblyopia leading to a poor prognosis. Case 2: A 7-year-old girl consulted for vision disturbance in her right eye. Visual acuity was finger counting at 2 meters in the right eye and 10/10 in the left eye. Anterior segment examination revealed no abnormalities in both eyes. However, fundus examination highlighted a large funnel-shaped excavation associated with central glial proliferation, wheel spoke vessels, and neuroretinal ring atrophy in the right eye. Optical coherence tomography (OCT) of the right eye confirmed the diagnosis of isolated unilateral Morning Glory syndrome. Management included full optical correction and orthoptic rehabilitation. The course was marked by the absence of ocular complication and maintenance of visual stability in the right eye. The prognosis seemed favorable. Conclusion: Congenital optic disc anomalies in children exhibit great clinical variability and require an individualized diagnostic and therapeutic approach.展开更多
The copper disc casting machine is core equipment for producing copper anode plates in the copper metallurgy industry.The copper disc casting machine casting package motion curve(CPMC) is significant for precise casti...The copper disc casting machine is core equipment for producing copper anode plates in the copper metallurgy industry.The copper disc casting machine casting package motion curve(CPMC) is significant for precise casting and efficient production.However,the lack of exact casting modeling and real-time simulation information severely restricts dynamic CPMC optimization.To this end,a liquid copper droplet model describes the casting package copper flow pattern in the casting process.Furthermore,a CPMC optimization model is proposed for the first time.On top of this,a digital twin dual closed-loop self-optimization application framework(DT-DCS) is constructed for optimizing the copper disc casting process to achieve self-optimization of the CPMC and closed-loop feedback of manufacturing information during the casting process.Finally,a case study is carried out based on the proposed methods in the industrial field.展开更多
The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped c...The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V vs.RHE) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.展开更多
AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control...AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control subjects were enrolled in the study.One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm^(2) rectangular area.Radial peripapillary capillary(RPC)density,peripapillary retinal nerve fiber layer(pRNFL)thickness,cup volume,rim area,disc area,cup-to-disc(c/d)area ratio,and vertical c/d ratio were obtained automatically using device software.Automated parapapillary choroidal microvasculature(PPCMv)density was calculated using MATLAB software.When the vertical c/d ratio of the optic disc was absent or small cup,it was considered as a crowded disc.RESULTS:The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes(P=0.740).There was no difference in pRNFL between the two groups(P=0.102).There were no differences in RPC density in whole image(P=0.826)and peripapillary region(P=0.923),but inside disc RPC density was higher in crowded optic discs(P=0.003).The PPCMv density in the inner-hemisuperior region was also lower in crowded discs(P=0.026).The pRNFL thickness was positively correlated with peripapillary RPC density(r=0.498,P<0.001).The inside disc RPC density was negatively correlated with c/d area ratio(r=-0.341,P=0.002).CONCLUSION:The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs.展开更多
Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis,...Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis, clinical evidence is limited. Objective: The purpose of this study is to provide high-quality evidence to support the effectiveness of the traditional Chinese hot and humid compress in the treatment of LDH with qi stagnation and blood stasis. Methods: From October 2021 to November 2023, 86 patients with LDH of qi stagnation and blood stasis type were recruited in our hospital and divided into a control (n = 43) and an observation group (n = 43) according to the random number table method. The control group was given routine clinical treatment, and the observation group was treated with the hot and humid compress therapy for two weeks. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, TCM syndrome score, serum interleukin-6 (IL-6), serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were observed and compared between the two groups before and after treatment, and the clinical efficacy of the two groups was evaluated. Results: After treatment, the VAS score, TCM symptom score, and serum IL-6, IL-1β, and TNF-α levels decreased in both groups (P P P P P Conclusions: The hot and humid compress of traditional Chinese medicine can effectively relieve pain, restore lumbar function, improve TCM syndromes, reduce the level of inflammatory factors, and have a curative effect in treating LDH.展开更多
BACKGROUND Lumbar disc herniation(LDH)commonly occurs during spinal surgery;LDH is on the increase in younger patients and is classified as"paralysis"and"back pain."Sanhanchushi Tongbi(SPST)is a cu...BACKGROUND Lumbar disc herniation(LDH)commonly occurs during spinal surgery;LDH is on the increase in younger patients and is classified as"paralysis"and"back pain."Sanhanchushi Tongbi(SPST)is a customized prescription.It disperses cold,relieves pain,removes cold from the meridians and viscera,and treats neuropathic pain.However,few studies have investigated its mechanism of pain relief.AIM To observe the clinical therapeutic effects on LDH treated with self-prescribed SPST.METHODS A total of 211 patients with LDH syndrome were divided into two groups:107 patients in the control group were treated with conventional massage combined with traction,and 104 patients in the observation group were treated with a combination of the control regimen and self-prescribed oral SPST.The patients were treated for 4 wk.Indices of traditional Chinese medicine(TCM)syndrome score and serum inflammatory factor levels were measured.RESULTS After therapy,the TCM syndrome score in the observation group was significantly lower than that in the control group(P<0.05).The main symptoms,clinical signs,daily activities,and Japanese Orthopedic Association scores in the observation group were significantly higher than those in the control group after therapy(P<0.05).The levels of tumor necrosis factor-α,interleukin-6,and C-reactive protein were lower in the observation group than in the control group(P<0.05).In the observation group,superoxide dismutase levels were significantly higher,whereas malondialdehyde levels were significantly lower,compared with the control group(P<0.05).The overall efficacy rate in the observation group was 96.15%,which was substantially higher than that in the control group(88.79%;P<0.05).CONCLUSION Self-prescribed SPST can reduce the levels of inflammatory and pain-causing factors as well as lumbar pain in patients with LDH.展开更多
Background:The incidence of lumbar disc herniation(LDH)is notably high.Consensus among experts highlights non-surgical treatments as the primary therapeutic approach for LDH.Contemporary medicine frequently employs ph...Background:The incidence of lumbar disc herniation(LDH)is notably high.Consensus among experts highlights non-surgical treatments as the primary therapeutic approach for LDH.Contemporary medicine frequently employs pharmacotherapy and epidural injections in such treatments,which are associated with numerous adverse effects.Prolonged use can severely impair the liver and kidney functions of patients.Hence,the role of safe and effective traditional Chinese medicine techniques becomes pivotal.Among various traditional Chinese medicine approaches for treating LDH,fire dragon cupping,renowned for its remarkable efficacy,cost-effectiveness,and ease of application,is extensively utilised in clinical settings for managing LDH.Nonetheless,there is a scarcity of systematic and standardised evidence from evidence-based medicine studies.Therefore,conducting a meta-analysis is imperative.Methods:A comprehensive computerised search was conducted in databases including China National Knowledge Infrastructure,WanFang Data,VIP,China Biology Medicine disc,PubMed,EMbase,The Cochrane Library,Web of Science,and CINAHL.The search aimed to gather randomised controlled trials on fire dragon cupping therapy for LDH,spanning from the inception of these databases until December 2023.Two researchers independently screened the literature according to inclusion and exclusion criteria,extracted data,and assessed the methodological quality of the studies included,utilising RevMan 5.3 software for meta-analysis.Results:The results show that the fire dragon cupping therapy group had better clinical effectiveness(relative risk=1.23,95%confidence interval(CI)(1.14,1.33),P<0.00001),less pain(standardized mean difference=–1.33,95%CI(–1.49,–1.16),P<0.00001),and some improvement in lumbar function(Japanese Orthopaedic Association scores:mean difference=3.37,95%CI(2.31,4.43),P<0.00001.Conclusion:The fire dragon cupping therapy significantly alleviates LDH,warranting its extensive application.However,considering the limitations in the number and quality of studies included,the aforementioned conclusion necessitates further validation through more high-quality research.展开更多
BACKGROUND This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion(UBE-LIF),utilizing the UBE's wide viewing field and operating space to perfo...BACKGROUND This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion(UBE-LIF),utilizing the UBE's wide viewing field and operating space to perform minimally invasive decompressive fusion of the lesioned segment,and the orthopedic surgical robot's intelligence and precision to perform percutaneous pedicle screw placement.The advancement of this procedure lies in the superposition of advantages and offsetting disadvantages of the two new technologies,and the maximum effect of treatment is achieved with maximum minimization of invasiveness and precision under the monitoring of imaging instruments to maximize the benefit of patients,and this review reports a case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE for reference.CASE SUMMARY A 44-year-old patient presented to our hospital.Combining various clinical data,we diagnosed the patient with lumbar disc herniation with radiculopathy,lumbar spondylolisthesis,and lumbar spinal stenosis.We developed a surgical plan of"UBE decompression+UBE-LIF+orthopedic surgery robot-assisted percutaneous pedicle screw implantation for internal fixation".The results were satisfactory.CONCLUSION We present an extremely rare case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE and achieved good results.Therefore,the technique is worthy of clinical promotion.展开更多
Introduction: Lumbar disc herniation (LDH) refers to the rupture of the fibrous annulus of the intervertebral discs. Lumbar curvature may lead to the occurrence of lumbar disc degeneration. Fear of movement may worsen...Introduction: Lumbar disc herniation (LDH) refers to the rupture of the fibrous annulus of the intervertebral discs. Lumbar curvature may lead to the occurrence of lumbar disc degeneration. Fear of movement may worsen their disc herniation and cause further pain and injury. LDH conditions impact the individuals’ quality of life, to explore the relationship between lumbar curve, muscle strength, fear of movement and functional disability among patients with LDH. Methods: An electronic search was conducted on PubMed, Medline, Science Direct, Springerlink, Google Scholar and a hand search from reference lists was reviewed. Publications were included in human studies, patients 25 - 85 years of age, original studies and published in English language journals from January 2002 to December 2023. Result: In total, 64 articles were researched through the online search engines, and 9 papers were found through manual searches of reference lists. As a result, a total of 11 articles were included for the purpose of this review. The comprehensive analysis revealed the presence of eight cross-sectional studies, two retrospective studies and one experimental study. A minimum of 25 participants and a maximum of 360 participants were included. Ten studies included both genders, only one studies included healthy adults and patients with LDH but these studies didn’t mention gender. Results showed that the factors influencing LDH can be categorized into non-modifiable factors, such as gender, age, height or others. Modifiable factors included increased BMI, DM, smoking, alcohol, employment status, lifestyle and health problems or psychology. Conclusion: Females with greater VASC may be at risk of LDH. The lumbar extensor muscles indicated a localized disc herniation or nerve root pathology in patients with LDH. The fear of movement may lead to psychological consequences and reduce functional disability among patients with LDH.展开更多
Lumbar disc herniation(LDH)is a common orthopedic disease in clinical practice,with main symptoms of varying degrees of pain and functional impairment,seriously affecting the quality of work and life of patients,and a...Lumbar disc herniation(LDH)is a common orthopedic disease in clinical practice,with main symptoms of varying degrees of pain and functional impairment,seriously affecting the quality of work and life of patients,and also causing a certain degree of economic burden to the patient's family and society.At present,there are various conservative treatment methods for LDH in clinical practice.Conservative treatment has the characteristics of small trauma and high safety,which can achieve symptom relief and cure for most patients in clinical practice.This article aims to provide a scientific reference for the selection of treatment plans for LDH patients by reviewing relevant literature on conservative treatment of LDH that has been publicly reported both domestically and internationally in recent years.展开更多
Objective:To observe the clinical effect of articular cavity injection combined with bite splint therapy for the treatment of anterior disc displacement without reduction(ADDWoR).Methods:The research subjects for this...Objective:To observe the clinical effect of articular cavity injection combined with bite splint therapy for the treatment of anterior disc displacement without reduction(ADDWoR).Methods:The research subjects for this study were 30 patients with ADDWoR treated in the temporomandibular joint specialist outpatient clinic from November 2018 to November 2019,with a disease duration of 1 to 6 months.The treatment group was treated with an articular cavity injection of sodium hyaluronate+bite splint.The control group was treated with a simple articular cavity injection of sodium hyaluronate.The two groups were followed up once every 2 weeks to evaluate the treatment effect and observe the clinical efficacy of the two groups.Statistical analysis was carried out using SPSS 24.0.t-test and general linear regression analysis were carried out to compare the data of both groups,andχ^(2)-test and binary logistic regression analysis were performed for pain index comparison.Results:There was no significant difference in terms of the efficacy of the treatment received by both groups.The mouth opening and joint pain of patients in both groups were significantly improved after treatment(P<0.001).Conclusion:Articular cavity injection of sodium hyaluronate and occlusal splint therapy are both effective and safe methods for treating ADDWoR.展开更多
Objective:To systematically evaluate the safety and efficacy of Mongolian medical warm acupuncture in the treatment of lumbar disc herniation(LDH).Methods:CNKI,Wanfang,VIP,Pubmed,Embase,Cochrane Library,and other data...Objective:To systematically evaluate the safety and efficacy of Mongolian medical warm acupuncture in the treatment of lumbar disc herniation(LDH).Methods:CNKI,Wanfang,VIP,Pubmed,Embase,Cochrane Library,and other databases were searched.The randomized controlled trials(RCTs)on the treatment of LDH with Mongolian medical warm acupuncture were manually searched in the Chinese Journal of Ethnic Medicine,Chinese Journal of Mongolian Medicine,Journal of Inner Mongolia University for Nationalities,and Journal of Inner Mongolia Medical University.The search time limit was from January 2000 to October 2023.RevMan5.4 software was used to analyze the included and excluded literature.Results:A total of 8 RCTs involving 1,042 patients with LDH were included,with 551 patients in the observation group and 491 patients in the control group.The results of the meta-analysis showed that a total of 8 randomized controlled trials were included in the treatment of LDH with Mongolian medical warm acupuncture compared with simple acupuncture(RR=1.18,95%CI=[1.12,1.23],P<0.00001).Conclusion:The total effective rate of Mongolian medical warm acupuncture for LDH is higher than that of simple acupuncture.However,due to the low quality of the literature included in this study,multi-dimensional,large sample size,and more rigorous clinical randomized trials are needed for further verification in the future.展开更多
Anterior cervical decompression and fusion(ACDF)treatment for cervical spondylosis has been more than half a century,and achieved good clinical results.However,with the continuous extension of follow-up time,the fusio...Anterior cervical decompression and fusion(ACDF)treatment for cervical spondylosis has been more than half a century,and achieved good clinical results.However,with the continuous extension of follow-up time,the fusion segment-associated postoperative complications emerged gradually.Reserved cervical stability and activity,the concept of non-fusion was born.As a non-fusion technique,cervical artificial disc replacement(CADR)developed rapidly.With the continuous development of artificial prosthesis materials and design concepts,and specification and proficiency of surgical procedures,CADR has achieved better short and mid-term clinical efficacy than ACDF.Compared with ACDF,the main advantages of CADR are that the postoperative recovery is quick,the activity and stability of cervical vertebra are maintained,the height of cervical intervertebral space is restored,and the stress of adjacent segments and the rate of surgical renovation are reduced.In clinical work,as an emerging technology,CADR requires spine surgeons to control the surgical indications,contraindications,and patients'conditions strictly.This article reviews the research progress of CADR in order to provide new ideas for clinical treatment of cervical spondylosis.展开更多
The degenerative disease of the intervertebral disc is nowadays an important health problem,which has still not been understood and solved adequately.The vertebral endplate is regarded as one of the vital elements in ...The degenerative disease of the intervertebral disc is nowadays an important health problem,which has still not been understood and solved adequately.The vertebral endplate is regarded as one of the vital elements in the structure of the intervertebral disc.Its constituent cells,the chondrocytes in the endplate,may also be involved in the process of the intervertebral disc degeneration and their role is central both under physiological and pathological conditions.They main functions include a role in homeostasis of the extracellular environment of the intervertebral disc,metabolic support and nutrition of the discal nucleus and annulus beneath and the preservation of the extracellular matrix.Therefore,it is understandable that the cells in the endplate have been in the centre of research from several viewpoints,such as development,degeneration and growth,reparation and remodelling,as well as treatment strategies.In this article,we briefly review the importance of vertebral endplate,which are often overlooked,in the intervertebral disc degeneration.展开更多
Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in ...Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in rodents,and therefore establishing a chronic spinal cord compression(CSCC)animal model is of crucial importance to explore the pathogenesis and treatment of CSCC.The absence of secreted protein,acidic,and rich in cysteine(SPARC)leads to spontaneous intervertebral disc degeneration in mice,which resembles human disc degeneration.In this study,we evaluated whether SPARC-null mice may serve as an animal model for CSCC.We performed rod rotation test,pain threshold test,gait analysis,and Basso Mouse Scale score.Our results showed that the motor function of SPARC-null mice was weakened,and magnetic resonance images revealed compression at different spinal cord levels,particularly in the lumbar segments.Immunofluorescence staining and western blot assay showed that the absence of SPARC induced apoptosis of neurons and oligodendrocytes,activation of microglia/macrophages with M1/M2 phenotype and astrocytes with A1/A2 phenotype;it also activated the expression of the NOD-like receptor protein 3 inflammasome and inhibited brain-derived neurotrophic factor/tyrosine kinase B signaling pathway.Notably,these findings are characteristics of CSCC.Therefore,we propose that SPARC-null mice may be an animal model for studying CSCC caused by disc herniation.展开更多
A plane mechanical model of rock breaking process by double disc cutter at the center of the cutterhead is established based on contact mechanics to analyze the stress evolution in the rock broken by cutters with diff...A plane mechanical model of rock breaking process by double disc cutter at the center of the cutterhead is established based on contact mechanics to analyze the stress evolution in the rock broken by cutters with different spacings. A continuous-discontinuous coupling numerical method based on zero-thickness cohesive elements is developed to simulate rock breaking using double cutters. The process, mechanism,and characteristics of rock breaking are comprehensively analyzed from five aspects: peak force, breaking form, breaking efficiency, crack mode, and breaking degree. The results show that under the penetrating action of cutters, dense cores are formed due to shear failure under respective cutters. The tensile cracks propagate in the rock, and then rock chips form with increasing penetration depth. When the cutter spacing is increased from 10 to 80 mm, the peak force gradually increases, the rock breaking range increases first and then decreases, the specific energy decreases first and then rises, and the breaking coefficient of intermediate rock decreases from 0.955 to 0.788. The area of rock breaking is positively correlated with the length of the tensile crack. Furthermore, the length of the tensile crack accounts for 14.4%–33.6% of the total crack length.展开更多
基金Deanship of Scientific Research,Princess Nourah bint Abdulrahman University,through the Program of Research Project Funding after Publication,Grant No(43-PRFA-P-31).
文摘Glaucoma disease causes irreversible damage to the optical nerve and it has the potential to cause permanent loss of vision.Glaucoma ranks as the second most prevalent cause of permanent blindness.Traditional glaucoma diagnosis requires a highly experienced specialist,costly equipment,and a lengthy wait time.For automatic glaucoma detection,state-of-the-art glaucoma detection methods include a segmentation-based method to calculate the cup-to-disc ratio.Other methods include multi-label segmentation networks and learning-based methods and rely on hand-crafted features.Localizing the optic disc(OD)is one of the key features in retinal images for detecting retinal diseases,especially for glaucoma disease detection.The approach presented in this study is based on deep classifiers for OD segmentation and glaucoma detection.First,the optic disc detection process is based on object detection using a Mask Region-Based Convolutional Neural Network(Mask-RCNN).The OD detection task was validated using the Dice score,intersection over union,and accuracy metrics.The OD region is then fed into the second stage for glaucoma detection.Therefore,considering only the OD area for glaucoma detection will reduce the number of classification artifacts by limiting the assessment to the optic disc area.For this task,VGG-16(Visual Geometry Group),Resnet-18(Residual Network),and Inception-v3 were pre-trained and fine-tuned.We also used the Support Vector Machine Classifier.The feature-based method uses region content features obtained by Histogram of Oriented Gradients(HOG)and Gabor Filters.The final decision is based on weighted fusion.A comparison of the obtained results from all classification approaches is provided.Classification metrics including accuracy and ROC curve are compared for each classification method.The novelty of this research project is the integration of automatic OD detection and glaucoma diagnosis in a global method.Moreover,the fusion-based decision system uses the glaucoma detection result obtained using several convolutional deep neural networks and the support vector machine classifier.These classification methods contribute to producing robust classification results.This method was evaluated using well-known retinal images available for research work and a combined dataset including retinal images with and without pathology.The performance of the models was tested on two public datasets and a combined dataset and was compared to similar research.The research findings show the potential of this methodology in the early detection of glaucoma,which will reduce diagnosis time and increase detection efficiency.The glaucoma assessment achieves about 98%accuracy in the classification rate,which is close to and even higher than that of state-of-the-art methods.The designed detection model may be used in telemedicine,healthcare,and computer-aided diagnosis systems.
基金supported by the Science and Technology Innovation Development Project of Yantai(No.2023ZDX016)。
文摘The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake discs.In this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical properties.Compacted graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of ferrite.The peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction tests.The morphology of thermal cracks and 3D profiles of the worn surfaces were also discussed.It is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue resistance.Oxidization of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal cracks.Despite the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.
文摘Introduction: Congenital optic disc anomalies in children refer to structural variations of the optic nerve head present from birth. These deformations involve the size, shape, color, and vessels of the optic disc. Although often asymptomatic, these anomalies can impact the visual development of the child, underscoring the importance of a thorough fundus examination for early detection and appropriate medical follow-up. We present two cases of congenital optic disc anomalies in children, illustrating the diagnostic challenges and complexity of their management. Case 1: A 3-year-old girl presented with a white spot in her left eye present since birth. Uncorrected distance visual acuity was 2/10 in the right eye, while she could perceive hand movements at 2 meters with the left eye. Normal examination in the right eye showed leukocoria, microphthalmia, and a white mass at the center of the optic disc on fundus examination in the left eye. Ocular imaging, including ultrasound and optical coherence tomography (OCT), confirmed the diagnosis of persistent hyperplastic primary vitreous (PHPV) in its mixed form in the left eye. Management included prescribing full optical correction and functional rehabilitation, without resorting to surgery. The course was marked by persistent amblyopia leading to a poor prognosis. Case 2: A 7-year-old girl consulted for vision disturbance in her right eye. Visual acuity was finger counting at 2 meters in the right eye and 10/10 in the left eye. Anterior segment examination revealed no abnormalities in both eyes. However, fundus examination highlighted a large funnel-shaped excavation associated with central glial proliferation, wheel spoke vessels, and neuroretinal ring atrophy in the right eye. Optical coherence tomography (OCT) of the right eye confirmed the diagnosis of isolated unilateral Morning Glory syndrome. Management included full optical correction and orthoptic rehabilitation. The course was marked by the absence of ocular complication and maintenance of visual stability in the right eye. The prognosis seemed favorable. Conclusion: Congenital optic disc anomalies in children exhibit great clinical variability and require an individualized diagnostic and therapeutic approach.
基金supported in part by the National Major Scientific Research Equipment of China (61927803)the National Natural Science Foundation of China Basic Science Center Project (61988101)+1 种基金Science and Technology Innovation Program of Hunan Province (2021RC4054)the China Postdoctoral Science Foundation (2021M691681)。
文摘The copper disc casting machine is core equipment for producing copper anode plates in the copper metallurgy industry.The copper disc casting machine casting package motion curve(CPMC) is significant for precise casting and efficient production.However,the lack of exact casting modeling and real-time simulation information severely restricts dynamic CPMC optimization.To this end,a liquid copper droplet model describes the casting package copper flow pattern in the casting process.Furthermore,a CPMC optimization model is proposed for the first time.On top of this,a digital twin dual closed-loop self-optimization application framework(DT-DCS) is constructed for optimizing the copper disc casting process to achieve self-optimization of the CPMC and closed-loop feedback of manufacturing information during the casting process.Finally,a case study is carried out based on the proposed methods in the industrial field.
基金Grant PID2020-115848RB-C21 "STORELEC" projectTED2021-129694B-C22 "DEFY-CO2" project funded by MCIN/AEI/10.13039/501100011033+3 种基金LMP253_ (2)1 project funded by Gobierno de AragónGrant IJC2019-041874-I funded by the MCIN/AEI/10.13039/501100011033CSIC for her JAE Intro ICU 2021-ICB-04 grantthe Y2020/EMT-6419 "CEOTRES" project funded by the Comunidad Autonoma de Madrid。
文摘The electrochemical CO_(2) reduction reaction(CO_(2)RR) to controllable chemicals is considered as a promising pathway to store intermittent renewable energy. Herein, a set of catalysts based on copper-nitrogendoped carbon xerogel(Cu-N-C) are successfully developed varying the copper amount and the nature of the copper precursor, for the efficient CO_(2)RR. The electrocatalytic performance of Cu-N-C materials is assessed by a rotating ring-disc electrode(RRDE), technique still rarely explored for CO_(2)RR. For comparison, products are also characterized by online gas chromatography in a H-cell. The as-synthesized Cu-NC catalysts are found to be active and highly CO selective at low overpotentials(from -0.6 to -0.8 V vs.RHE) in 0.1 M KHCO_(3), while H_(2) from the competitive water reduction appears at larger overpotentials(-0.9 V vs. RHE). The optimum copper acetate-derived catalyst containing Cu-N_(4) moieties exhibits a CO_(2)-to-CO turnover frequency of 997 h^(-1) at -0.9 V vs. RHE with a H_(2)/CO ratio of 1.8. These results demonstrate that RRDE configuration can be used as a feasible approach for identifying electrolysis products from CO_(2)RR.
文摘AIM:To compare superficial and deep vascular properties of optic discs between crowded discs and controls using optical coherence tomography angiography(OCT-A).METHODS:Thirty patients with crowded discs,and 47 control subjects were enrolled in the study.One eye of each individual was included and OCT-A scans of optic discs were obtained in a 4.5×4.5 mm^(2) rectangular area.Radial peripapillary capillary(RPC)density,peripapillary retinal nerve fiber layer(pRNFL)thickness,cup volume,rim area,disc area,cup-to-disc(c/d)area ratio,and vertical c/d ratio were obtained automatically using device software.Automated parapapillary choroidal microvasculature(PPCMv)density was calculated using MATLAB software.When the vertical c/d ratio of the optic disc was absent or small cup,it was considered as a crowded disc.RESULTS:The mean signal strength index of OCT-A images was similar between the crowded discs and control eyes(P=0.740).There was no difference in pRNFL between the two groups(P=0.102).There were no differences in RPC density in whole image(P=0.826)and peripapillary region(P=0.923),but inside disc RPC density was higher in crowded optic discs(P=0.003).The PPCMv density in the inner-hemisuperior region was also lower in crowded discs(P=0.026).The pRNFL thickness was positively correlated with peripapillary RPC density(r=0.498,P<0.001).The inside disc RPC density was negatively correlated with c/d area ratio(r=-0.341,P=0.002).CONCLUSION:The higher inside disc RPC density and lower inner-hemisuperior PPCMv density are found in eyes with crowded optic discs.
文摘Background: Although a number of studies have reported that the hot and humid compress from traditional Chinese medicine (TCM) is effective in treating lumbar disc herniation (LDH) with qi stagnation and blood stasis, clinical evidence is limited. Objective: The purpose of this study is to provide high-quality evidence to support the effectiveness of the traditional Chinese hot and humid compress in the treatment of LDH with qi stagnation and blood stasis. Methods: From October 2021 to November 2023, 86 patients with LDH of qi stagnation and blood stasis type were recruited in our hospital and divided into a control (n = 43) and an observation group (n = 43) according to the random number table method. The control group was given routine clinical treatment, and the observation group was treated with the hot and humid compress therapy for two weeks. The visual analogue scale (VAS) score, Japanese Orthopaedic Association (JOA) score, TCM syndrome score, serum interleukin-6 (IL-6), serum interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) were observed and compared between the two groups before and after treatment, and the clinical efficacy of the two groups was evaluated. Results: After treatment, the VAS score, TCM symptom score, and serum IL-6, IL-1β, and TNF-α levels decreased in both groups (P P P P P Conclusions: The hot and humid compress of traditional Chinese medicine can effectively relieve pain, restore lumbar function, improve TCM syndromes, reduce the level of inflammatory factors, and have a curative effect in treating LDH.
文摘BACKGROUND Lumbar disc herniation(LDH)commonly occurs during spinal surgery;LDH is on the increase in younger patients and is classified as"paralysis"and"back pain."Sanhanchushi Tongbi(SPST)is a customized prescription.It disperses cold,relieves pain,removes cold from the meridians and viscera,and treats neuropathic pain.However,few studies have investigated its mechanism of pain relief.AIM To observe the clinical therapeutic effects on LDH treated with self-prescribed SPST.METHODS A total of 211 patients with LDH syndrome were divided into two groups:107 patients in the control group were treated with conventional massage combined with traction,and 104 patients in the observation group were treated with a combination of the control regimen and self-prescribed oral SPST.The patients were treated for 4 wk.Indices of traditional Chinese medicine(TCM)syndrome score and serum inflammatory factor levels were measured.RESULTS After therapy,the TCM syndrome score in the observation group was significantly lower than that in the control group(P<0.05).The main symptoms,clinical signs,daily activities,and Japanese Orthopedic Association scores in the observation group were significantly higher than those in the control group after therapy(P<0.05).The levels of tumor necrosis factor-α,interleukin-6,and C-reactive protein were lower in the observation group than in the control group(P<0.05).In the observation group,superoxide dismutase levels were significantly higher,whereas malondialdehyde levels were significantly lower,compared with the control group(P<0.05).The overall efficacy rate in the observation group was 96.15%,which was substantially higher than that in the control group(88.79%;P<0.05).CONCLUSION Self-prescribed SPST can reduce the levels of inflammatory and pain-causing factors as well as lumbar pain in patients with LDH.
基金supported by the 2022 study on the effectiveness of Fire Dragon Cupping in treating cold-dampness obstructive type shoulder stiffness,funded by the Bao'an District Healthcare Research Project in Shenzhen(Shen Bao Ke[2023]No.13,Project No.2022JD237)2023 study on the therapeutic observation and mechanism exploration of Fire Dragon Cupping in cold-dampness obstructive type acute gout,funded by the Guangdong Provincial Administration of Traditional Chinese Medicine(Yue Zhong Yi Han[2023]No.205,Project No.20242077)+1 种基金National Clinical Key Specialty(Traditional Chinese Medicine)Construction Project(2013-239)Sanming Project of Medicine in Shenzhen(No.SZZYSM202206014).
文摘Background:The incidence of lumbar disc herniation(LDH)is notably high.Consensus among experts highlights non-surgical treatments as the primary therapeutic approach for LDH.Contemporary medicine frequently employs pharmacotherapy and epidural injections in such treatments,which are associated with numerous adverse effects.Prolonged use can severely impair the liver and kidney functions of patients.Hence,the role of safe and effective traditional Chinese medicine techniques becomes pivotal.Among various traditional Chinese medicine approaches for treating LDH,fire dragon cupping,renowned for its remarkable efficacy,cost-effectiveness,and ease of application,is extensively utilised in clinical settings for managing LDH.Nonetheless,there is a scarcity of systematic and standardised evidence from evidence-based medicine studies.Therefore,conducting a meta-analysis is imperative.Methods:A comprehensive computerised search was conducted in databases including China National Knowledge Infrastructure,WanFang Data,VIP,China Biology Medicine disc,PubMed,EMbase,The Cochrane Library,Web of Science,and CINAHL.The search aimed to gather randomised controlled trials on fire dragon cupping therapy for LDH,spanning from the inception of these databases until December 2023.Two researchers independently screened the literature according to inclusion and exclusion criteria,extracted data,and assessed the methodological quality of the studies included,utilising RevMan 5.3 software for meta-analysis.Results:The results show that the fire dragon cupping therapy group had better clinical effectiveness(relative risk=1.23,95%confidence interval(CI)(1.14,1.33),P<0.00001),less pain(standardized mean difference=–1.33,95%CI(–1.49,–1.16),P<0.00001),and some improvement in lumbar function(Japanese Orthopaedic Association scores:mean difference=3.37,95%CI(2.31,4.43),P<0.00001.Conclusion:The fire dragon cupping therapy significantly alleviates LDH,warranting its extensive application.However,considering the limitations in the number and quality of studies included,the aforementioned conclusion necessitates further validation through more high-quality research.
基金Supported by National Natural Science Foundation of China(Regional Program),No.82060879,No.82360947Gansu Province Key Talent Project,No.2024-4+2 种基金Natural Science Foundation of Gansu Province,No.20JR10RA356Gansu Provincial Joint Research Fund,No.23JRRA1534National Administration of Traditional Chinese Medicine High Level Key Discipline Construction Project of Traditional Chinese Medicine(Traditional Chinese Orthopedics and Traumatology Science),No.203.
文摘BACKGROUND This reported procedure combines the orthopedic surgical robot with the unilateral biportal endoscopy-lumbar interbody fusion(UBE-LIF),utilizing the UBE's wide viewing field and operating space to perform minimally invasive decompressive fusion of the lesioned segment,and the orthopedic surgical robot's intelligence and precision to perform percutaneous pedicle screw placement.The advancement of this procedure lies in the superposition of advantages and offsetting disadvantages of the two new technologies,and the maximum effect of treatment is achieved with maximum minimization of invasiveness and precision under the monitoring of imaging instruments to maximize the benefit of patients,and this review reports a case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE for reference.CASE SUMMARY A 44-year-old patient presented to our hospital.Combining various clinical data,we diagnosed the patient with lumbar disc herniation with radiculopathy,lumbar spondylolisthesis,and lumbar spinal stenosis.We developed a surgical plan of"UBE decompression+UBE-LIF+orthopedic surgery robot-assisted percutaneous pedicle screw implantation for internal fixation".The results were satisfactory.CONCLUSION We present an extremely rare case of multiple-segment lumbar decompression and fusion surgery for lumbar disc herniation via robot-assisted UBE and achieved good results.Therefore,the technique is worthy of clinical promotion.
文摘Introduction: Lumbar disc herniation (LDH) refers to the rupture of the fibrous annulus of the intervertebral discs. Lumbar curvature may lead to the occurrence of lumbar disc degeneration. Fear of movement may worsen their disc herniation and cause further pain and injury. LDH conditions impact the individuals’ quality of life, to explore the relationship between lumbar curve, muscle strength, fear of movement and functional disability among patients with LDH. Methods: An electronic search was conducted on PubMed, Medline, Science Direct, Springerlink, Google Scholar and a hand search from reference lists was reviewed. Publications were included in human studies, patients 25 - 85 years of age, original studies and published in English language journals from January 2002 to December 2023. Result: In total, 64 articles were researched through the online search engines, and 9 papers were found through manual searches of reference lists. As a result, a total of 11 articles were included for the purpose of this review. The comprehensive analysis revealed the presence of eight cross-sectional studies, two retrospective studies and one experimental study. A minimum of 25 participants and a maximum of 360 participants were included. Ten studies included both genders, only one studies included healthy adults and patients with LDH but these studies didn’t mention gender. Results showed that the factors influencing LDH can be categorized into non-modifiable factors, such as gender, age, height or others. Modifiable factors included increased BMI, DM, smoking, alcohol, employment status, lifestyle and health problems or psychology. Conclusion: Females with greater VASC may be at risk of LDH. The lumbar extensor muscles indicated a localized disc herniation or nerve root pathology in patients with LDH. The fear of movement may lead to psychological consequences and reduce functional disability among patients with LDH.
文摘Lumbar disc herniation(LDH)is a common orthopedic disease in clinical practice,with main symptoms of varying degrees of pain and functional impairment,seriously affecting the quality of work and life of patients,and also causing a certain degree of economic burden to the patient's family and society.At present,there are various conservative treatment methods for LDH in clinical practice.Conservative treatment has the characteristics of small trauma and high safety,which can achieve symptom relief and cure for most patients in clinical practice.This article aims to provide a scientific reference for the selection of treatment plans for LDH patients by reviewing relevant literature on conservative treatment of LDH that has been publicly reported both domestically and internationally in recent years.
文摘Objective:To observe the clinical effect of articular cavity injection combined with bite splint therapy for the treatment of anterior disc displacement without reduction(ADDWoR).Methods:The research subjects for this study were 30 patients with ADDWoR treated in the temporomandibular joint specialist outpatient clinic from November 2018 to November 2019,with a disease duration of 1 to 6 months.The treatment group was treated with an articular cavity injection of sodium hyaluronate+bite splint.The control group was treated with a simple articular cavity injection of sodium hyaluronate.The two groups were followed up once every 2 weeks to evaluate the treatment effect and observe the clinical efficacy of the two groups.Statistical analysis was carried out using SPSS 24.0.t-test and general linear regression analysis were carried out to compare the data of both groups,andχ^(2)-test and binary logistic regression analysis were performed for pain index comparison.Results:There was no significant difference in terms of the efficacy of the treatment received by both groups.The mouth opening and joint pain of patients in both groups were significantly improved after treatment(P<0.001).Conclusion:Articular cavity injection of sodium hyaluronate and occlusal splint therapy are both effective and safe methods for treating ADDWoR.
文摘Objective:To systematically evaluate the safety and efficacy of Mongolian medical warm acupuncture in the treatment of lumbar disc herniation(LDH).Methods:CNKI,Wanfang,VIP,Pubmed,Embase,Cochrane Library,and other databases were searched.The randomized controlled trials(RCTs)on the treatment of LDH with Mongolian medical warm acupuncture were manually searched in the Chinese Journal of Ethnic Medicine,Chinese Journal of Mongolian Medicine,Journal of Inner Mongolia University for Nationalities,and Journal of Inner Mongolia Medical University.The search time limit was from January 2000 to October 2023.RevMan5.4 software was used to analyze the included and excluded literature.Results:A total of 8 RCTs involving 1,042 patients with LDH were included,with 551 patients in the observation group and 491 patients in the control group.The results of the meta-analysis showed that a total of 8 randomized controlled trials were included in the treatment of LDH with Mongolian medical warm acupuncture compared with simple acupuncture(RR=1.18,95%CI=[1.12,1.23],P<0.00001).Conclusion:The total effective rate of Mongolian medical warm acupuncture for LDH is higher than that of simple acupuncture.However,due to the low quality of the literature included in this study,multi-dimensional,large sample size,and more rigorous clinical randomized trials are needed for further verification in the future.
文摘Anterior cervical decompression and fusion(ACDF)treatment for cervical spondylosis has been more than half a century,and achieved good clinical results.However,with the continuous extension of follow-up time,the fusion segment-associated postoperative complications emerged gradually.Reserved cervical stability and activity,the concept of non-fusion was born.As a non-fusion technique,cervical artificial disc replacement(CADR)developed rapidly.With the continuous development of artificial prosthesis materials and design concepts,and specification and proficiency of surgical procedures,CADR has achieved better short and mid-term clinical efficacy than ACDF.Compared with ACDF,the main advantages of CADR are that the postoperative recovery is quick,the activity and stability of cervical vertebra are maintained,the height of cervical intervertebral space is restored,and the stress of adjacent segments and the rate of surgical renovation are reduced.In clinical work,as an emerging technology,CADR requires spine surgeons to control the surgical indications,contraindications,and patients'conditions strictly.This article reviews the research progress of CADR in order to provide new ideas for clinical treatment of cervical spondylosis.
文摘The degenerative disease of the intervertebral disc is nowadays an important health problem,which has still not been understood and solved adequately.The vertebral endplate is regarded as one of the vital elements in the structure of the intervertebral disc.Its constituent cells,the chondrocytes in the endplate,may also be involved in the process of the intervertebral disc degeneration and their role is central both under physiological and pathological conditions.They main functions include a role in homeostasis of the extracellular environment of the intervertebral disc,metabolic support and nutrition of the discal nucleus and annulus beneath and the preservation of the extracellular matrix.Therefore,it is understandable that the cells in the endplate have been in the centre of research from several viewpoints,such as development,degeneration and growth,reparation and remodelling,as well as treatment strategies.In this article,we briefly review the importance of vertebral endplate,which are often overlooked,in the intervertebral disc degeneration.
基金supported by the National Natural Science Foundation of China,Nos.82074454(to XJC),82174409(to MY),81930116(to YJW),81873317(to XJC)the National Key R&D Program of China,No.2018YFC1704300(to YJW)the Natural Science Foundation of Shanghai,No.20ZR1459000(to MY)。
文摘Chronic spinal cord compression(CSCC)is induced by disc herniation and other reasons,leading to movement and sensation dysfunction,with a serious impact on quality of life.Spontaneous disc herniation rarely occurs in rodents,and therefore establishing a chronic spinal cord compression(CSCC)animal model is of crucial importance to explore the pathogenesis and treatment of CSCC.The absence of secreted protein,acidic,and rich in cysteine(SPARC)leads to spontaneous intervertebral disc degeneration in mice,which resembles human disc degeneration.In this study,we evaluated whether SPARC-null mice may serve as an animal model for CSCC.We performed rod rotation test,pain threshold test,gait analysis,and Basso Mouse Scale score.Our results showed that the motor function of SPARC-null mice was weakened,and magnetic resonance images revealed compression at different spinal cord levels,particularly in the lumbar segments.Immunofluorescence staining and western blot assay showed that the absence of SPARC induced apoptosis of neurons and oligodendrocytes,activation of microglia/macrophages with M1/M2 phenotype and astrocytes with A1/A2 phenotype;it also activated the expression of the NOD-like receptor protein 3 inflammasome and inhibited brain-derived neurotrophic factor/tyrosine kinase B signaling pathway.Notably,these findings are characteristics of CSCC.Therefore,we propose that SPARC-null mice may be an animal model for studying CSCC caused by disc herniation.
基金funded by the National Key Research and Development Program of China (No. 2021YFB3401501)the Fundamental Research Funds for the Central Universities (No2022JCCXLJ01)。
文摘A plane mechanical model of rock breaking process by double disc cutter at the center of the cutterhead is established based on contact mechanics to analyze the stress evolution in the rock broken by cutters with different spacings. A continuous-discontinuous coupling numerical method based on zero-thickness cohesive elements is developed to simulate rock breaking using double cutters. The process, mechanism,and characteristics of rock breaking are comprehensively analyzed from five aspects: peak force, breaking form, breaking efficiency, crack mode, and breaking degree. The results show that under the penetrating action of cutters, dense cores are formed due to shear failure under respective cutters. The tensile cracks propagate in the rock, and then rock chips form with increasing penetration depth. When the cutter spacing is increased from 10 to 80 mm, the peak force gradually increases, the rock breaking range increases first and then decreases, the specific energy decreases first and then rises, and the breaking coefficient of intermediate rock decreases from 0.955 to 0.788. The area of rock breaking is positively correlated with the length of the tensile crack. Furthermore, the length of the tensile crack accounts for 14.4%–33.6% of the total crack length.