cone

圆锥体
  • 文章类型: Journal Article
    冷杉是松科的重要属,在亚洲的高地发现了大约50个物种,欧洲,北非,北美和中美洲。本工作的主要目的是研究冷杉的树脂和锥的化学含量和生物潜力。bornmulleriana和冷杉nordmanniana亚种。equi-trojani,分别。使用液相色谱-高分辨率质谱(LC-HRMS)评估树脂和视锥的类黄酮和酚类含量。此外,使用气相色谱-质谱(GC-MS)和气相色谱-火焰离子化检测器(GC-FID)分析精油和脂肪酸组成,分别。对某些癌细胞系筛选提取物和精油的细胞毒性,即,人前列腺腺癌细胞系(PC3),人肺腺癌细胞系(A549),人胰腺癌细胞系(PANC-1),人肝癌细胞系(HepG2),人乳腺癌细胞系(MDA-MB231),和正常人肺成纤维细胞系(CCD-34-LU),用MTT[3-(4,5-二甲基噻唑-2-基)-2,5-二苯基-2H-四唑溴化物]测定。根据MTT结果,正己烷萃取物(CH)和树脂萃取物(RH),乙醇-水(CEW),二氯甲烷(CD),锥体的丙酮(CA)提取物大多对HepG2细胞系造成细胞毒性。冷杉亚种的抗病毒活性。还在卵中评估了5μg/g和10μg/g剂量的提取物对禽类冠状病毒的杀病毒活性。冷杉nordmanniana亚种。提取物对无特定病原体的含胚鸡蛋表现出浓度依赖性的抗病毒活性。重要的是,锥形丙酮提取物(CA),浓缩乙醇提取物(CE),冷杉亚种和浓二氯甲烷提取物(CD)。在10μg/g的浓度下表现出对病毒的强烈抑制作用。用针叶树形式的乙醇-水提取物(CEW)观察到最有效的杀病毒活性。根据这些结果,事实证明,冷杉品种可能是潜在的,可持续,和可再生的药物来源,特别是考虑到令人印象深刻的抗病毒和显着的细胞毒活性潜力。
    Abies is an important genus of the family Pinaceae, with about 50 species found in the highlands of Asia, Europe, North Africa, and North and Central America. The principal aim of the present work was to investigate the chemical content and biological potential of the resin and cone from Abies nordmanniana subsp. bornmulleriana and Abies nordmanniana subsp. equi-trojani, respectively. The flavonoid and phenolic contents of the resin and cones were evaluated using liquid chromatography-high resolution mass spectrometry (LC-HRMS). Additionally, the essential oil and fatty acid compositions were analyzed using gas chromatography-mass spectrometry (GC-MS) and gas chromatography-flame ionization detector (GC-FID), respectively. Cytotoxicity of the extracts and essential oils were screened against certain cancer cell lines, namely, human prostate adenocarcinoma cell line (PC3), human lung adenocarcinoma cell line (A549), human pancreatic cancer cell line (PANC-1), human hepatocellular carcinoma cell line (HepG2), human breast cancer cell line (MDA-MB231), and normal human lung fibroblast cell line (CCD-34-LU), with MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay. According to the MTT results, hexane extracts of both cone (CH) and resin (RH), ethanol-water (CEW), dichloromethane (CD), and acetone (CA) extracts of the cone mostly inflict cytotoxicity in HepG2 cell line. Antiviral activities of Abies nordmanniana subsp. extracts at doses of 5 μg/g and 10 μg/g were also evaluated in ovo for their virucidal activity against avian coronavirus. Abies nordmanniana subsp. extracts exhibited concentration-dependent antiviral activity on specific pathogen-free embryonated chicken eggs. Significantly, cone acetone extract (CA), cone ethanol extract (CE), and cone dichloromethane extract (CD) of Abies nordmanniana subsp. exhibited strong inhibition of the virus at a concentration of 10 μg/g. The most potent virucidal activity was observed with ethanol-water extract of conifer form (CEW). According to these results, it was proved that Abies nordmanniana species could be a potential, sustainable, and renewable drug source, especially considering the impressive antiviral and significant cytotoxic activity potentials.
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  • 文章类型: Journal Article
    甲状腺激素(TH)在细胞增殖中起着至关重要的作用,分化,和新陈代谢。实验和临床研究表明,TH信号与视网膜变性之间存在潜在的关联。抑制TH信号保护视网膜变性小鼠模型中的视锥细胞,而过度的TH信号诱导视锥细胞变性,表现为减少的光响应和锥体的损失。这项工作使用单细胞RNA测序(scRNAseq)分析研究了可能参与TH诱导的小鼠视锥变性的基因/转录组改变。一个月大的C57BL/6小鼠接受三碘甲状腺原氨酸(T3,饮用水中20µg/mL)4周作为甲状腺功能亢进/过度TH信号传导的模型。在实验结束时,视网膜细胞解离,并在进行scRNAseq之前分析细胞活力。使用Seurat软件包分析所得数据,并使用Loupe浏览器进行可视化。在155,866个单细胞中,我们确定了14个细胞簇,代表各种视网膜细胞类型,杆状和锥形簇占总细胞群的76%和4.1%,分别。在T3治疗后,锥形簇转录组表现出最大的变化,具有450个差异表达基因(DEGs),占总DEG的38.5%。视锥簇中基因表达的统计学显着变化表明,T3处理后,光转导和氧化磷酸化受损,以及线粒体功能障碍。途径分析还显示了T3处理后感觉神经元/光感受器应激途径的激活。具体来说,真核起始因子2信号通路和cAMP反应元件结合蛋白信号通路上调。因此,过度的TH信号在转录组水平上显著影响视锥细胞。这项工作的发现提供了对过度TH信号如何诱导视锥退化的见解。
    Thyroid hormone (TH) plays an essential role in cell proliferation, differentiation, and metabolism. Experimental and clinical studies have shown a potential association between TH signaling and retinal degeneration. The suppression of TH signaling protects cone photoreceptors in mouse models of retinal degeneration, whereas excessive TH signaling induces cone degeneration, manifested as reduced light response and a loss of cones. This work investigates the genes/transcriptomic alterations that might be involved in TH-induced cone degeneration in mice using single-cell RNA sequencing (scRNAseq) analysis. One-month-old C57BL/6 mice received triiodothyronine (T3, 20 µg/mL in drinking water) for 4 weeks as a model of hyperthyroidism/excessive TH signaling. At the end of the experiments, retinal cells were dissociated, and cell viability was analyzed before being subjected to scRNAseq. The resulting data were analyzed using the Seurat package and visualized using the Loupe browser. Among 155,866 single cells, we identified 14 cell clusters, representing various retinal cell types, with rod and cone clusters comprising 76% and 4.1% of the total cell population, respectively. Cone cluster transcriptomes demonstrated the most alterations after the T3 treatment, with 450 differentially expressed genes (DEGs), accounting for 38.5% of the total DEGs. Statistically significant changes in the expression of genes in the cone cluster revealed that phototransduction and oxidative phosphorylation were impaired after the T3 treatment, along with mitochondrial dysfunction. A pathway analysis also showed the activation of the sensory neuronal/photoreceptor stress pathways after the T3 treatment. Specifically, the eukaryotic initiation factor-2 signaling pathway and the cAMP response element-binding protein signaling pathway were upregulated. Thus, excessive TH signaling substantially affects cones at the transcriptomic level. The findings from this work provide an insight into how excessive TH signaling induces cone degeneration.
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  • 文章类型: Journal Article
    背景:铁诱导的氧化应激被认为是当铁离子存在时视网膜电图(ERG)的a波振幅下降的原因。假设在铁离子存在下产生活性氧(ROS),这导致感光体的超极化减少。众所周知,在年龄相关性黄斑变性(AMD)中,碘酸钠可以诱导氧化应激,凋亡,和视网膜损伤,模拟临床AMD的影响。这里,解释了碘酸钠诱导的年龄相关性黄斑变性小鼠a波振幅的降低。
    方法:a波的前缘被分成由锥体和杆形成的电压。同样的氧化应激模型也适用于此,因为碘酸钠以类似于铁离子引起的方式产生ROS,例外的是,当计算光响应时,视网膜被视为具有各种电阻的电路。此外,碘酸钠也会导致细胞凋亡,因此,在AMD细胞凋亡的初始阶段,可能会导致视锥细胞(而不是视杆)错位。包括视锥细胞和视杆细胞凋亡和缩短的影响,我们已经使用了一个因子来表示活的全部视锥和杆的分数。为了包括锥体不对准对a波振幅减小的影响,我们已经使用Stiles-Crawford函数来计算在角度θ未对准的感光体中发生的光异构化的数量。将结果与实验数据进行比较。
    结果:在碘酸钠治疗的眼睛中,产生的ROS可以吸引感光体中的钙离子,这增加了钙的流入。在锥体的情况下,在光传导过程中包含未对准角有助于确定电压和电压的斜率与时间图。活性光感受器的比例越小,a波的振幅越小。钙的流入,错位的光感受器,和感光体的总损失都会导致a波的振幅降低,从光传导级联开始的任何时候,钙流入导致a波的斜率增加。
    结论:碘酸钠处理的小鼠眼睛中a波振幅的降低归因于视锥和视杆的氧化应激和视锥错位,最终导致AMD的细胞凋亡和视力丧失。
    Iron-induced oxidative stress was thought to be the reason why the a-wave amplitude of the electroretinogram (ERG) dropped when iron ions were present. It is assumed that reactive oxygen species (ROS) are generated in the presence of iron ions, and this leads to a decrease in hyperpolarization of the photoreceptor. It is known that in age-related macular degeneration (AMD), sodium iodate can induce oxidative stress, apoptosis, and retinal damage, which mimic the effects of clinical AMD. Here, the reduction of the a-wave amplitude in mice with sodium iodate-induced age-related macular degeneration is explained.
    The leading edge of the a-wave is divided into voltages developed by cones and rods. The same oxidative stress model is applied here since sodium iodate causes the creation of ROS in a manner similar to that caused by iron ions, with the exception that the retina is treated as a circuit of various resistances when computing the photoresponse. Moreover, sodium iodate also leads to apoptosis and, hence, may cause misalignment in cones (not in rods) during the initial stage of apoptosis in AMD. To include the effects of apoptosis and shortening in cones and rods, we have used a factor representing the fraction of total cones and rods that are alive. To include the effect of misalignment of cones on the reduction of the a-wave amplitude, we have used the Stiles-Crawford function to calculate the number of photoisomerizations occurring in a photoreceptor misaligned at an angle θ. The results are compared with experimental data.
    In sodium iodate-treated eyes, the ROS produced can attract calcium ions in the photoreceptor, which increases the calcium influx. In the case of the cones, the inclusion of the misalignment angle in the phototransduction process helps in determining the voltage and slope of the voltage vs. time graph.The smaller the fraction of active photoreceptors, the smaller the amplitude of the a-wave. The calcium influx, misaligned photoreceptors, and total photoreceptor loss all cause the amplitude of the a-wave to decrease, and at any time from the beginning of phototransduction cascade, the calcium influx causes the slope of the a-wave to increase.
    The reduction in the a-wave amplitude in the eyes of sodium iodate-treated mice is attributed to oxidative stress in both cones and rods and cone misalignment, which ultimately lead to apoptosis and vision loss in AMD.
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  • 文章类型: Journal Article
    光感受器的功能,棒,锥体高度依赖于它们的外段(POS),含有高度组织化膜结构的细胞区室,从入射光中产生生化信号。虽然在显微镜图像上定性地评估了POS的形成和变性,可靠的定量分析方法仍然有限。这里,我们开发了使用自动图像分析量化视网膜切片上POS(QuaPOS)成熟度和质量的方法.通过光学显微镜(LM)和透射电子显微镜(TEM)检查了野生型小鼠在发育过程中和成年期的POS形成。为了量化数字,尺寸,形状,和POS的荧光强度,对视网膜冷冻切片进行视锥POS标记S-视蛋白免疫染色。使用荧光图像来训练基于监督机器学习的鲁棒分类器QuaPOS-LM以用于自动图像分割。提取分割结果的特征以量化锥体POS的成熟度。随后,该定量方法用于表征“视锥细胞功能丧失1”小鼠的POS变性。TEM图像用于建立用于POS膜对准的超微结构定量方法QuaPOS-TEM。使用自定义编写的MATLAB代码分析图像,以从图像梯度和它们的对齐(相干性)中提取膜的方向。此分析用于量化野生型和两个遗传性视网膜变性(“视网膜变性19”和“视紫红质敲除”)小鼠系的POS形态。两种自动分析技术都基于LM或TEM图像提供了对POS的鲁棒表征和量化。通过分类器QuaPOS-LM进行自动图像分割,并通过QuaPOS-TEM使用荧光或TEM图像分析膜堆叠的方向,可以定量评估POS的形成和质量。评估显示POS数量增加,volume,和野生型出生后发育过程中的膜相干性,而在不同的视网膜变性小鼠模型中检测到所有三个可观察值的减少。用于所呈现的分析的所有代码都是开源的,包括示例数据集以重现发现。因此,QuaPOS定量方法可用于在发育研究中深入表征视网膜切片上的POS,用于疾病建模,或在影响光感受器的治疗干预之后。
    The functionality of photoreceptors, rods, and cones is highly dependent on their outer segments (POS), a cellular compartment containing highly organized membranous structures that generate biochemical signals from incident light. While POS formation and degeneration are qualitatively assessed on microscopy images, reliable methodology for quantitative analyses is still limited. Here, we developed methods to quantify POS (QuaPOS) maturation and quality on retinal sections using automated image analyses. POS formation was examined during the development and in adulthood of wild-type mice via light microscopy (LM) and transmission electron microscopy (TEM). To quantify the number, size, shape, and fluorescence intensity of POS, retinal cryosections were immunostained for the cone POS marker S-opsin. Fluorescence images were used to train the robust classifier QuaPOS-LM based on supervised machine learning for automated image segmentation. Characteristic features of segmentation results were extracted to quantify the maturation of cone POS. Subsequently, this quantification method was applied to characterize POS degeneration in \"cone photoreceptor function loss 1\" mice. TEM images were used to establish the ultrastructural quantification method QuaPOS-TEM for the alignment of POS membranes. Images were analyzed using a custom-written MATLAB code to extract the orientation of membranes from the image gradient and their alignment (coherency). This analysis was used to quantify the POS morphology of wild-type and two inherited retinal degeneration (\"retinal degeneration 19\" and \"rhodopsin knock-out\") mouse lines. Both automated analysis technologies provided robust characterization and quantification of POS based on LM or TEM images. Automated image segmentation by the classifier QuaPOS-LM and analysis of the orientation of membrane stacks by QuaPOS-TEM using fluorescent or TEM images allowed quantitative evaluation of POS formation and quality. The assessments showed an increase in POS number, volume, and membrane coherency during wild-type postnatal development, while a decrease in all three observables was detected in different retinal degeneration mouse models. All the code used for the presented analysis is open source, including example datasets to reproduce the findings. Hence, the QuaPOS quantification methods are useful for in-depth characterization of POS on retinal sections in developmental studies, for disease modeling, or after therapeutic interventions affecting photoreceptors.
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  • 文章类型: Journal Article
    色盲是一种视网膜疾病,主要表现为色觉障碍,以色盲为特征,红绿色盲,还有蓝黄色盲.随着技术的发展和理论的进步,已经对色盲的遗传基础进行了广泛的研究,并探索了各种治疗方法。本文旨在提供一个全面的综述,了解病理机制的最新进展,临床症状,和色盲的治疗选择。此外,我们讨论了为解决色盲而开发的各种治疗方法,包括基因疗法,药理干预,和视觉辅助。此外,我们强调了这些治疗方法的临床试验的有希望的结果,以及实现有效和持久的治疗结果必须解决的持续挑战。总的来说,这篇综述提供了对色盲研究现状的宝贵见解,目的是为进一步研究和开发这种疾病的有效治疗方法提供信息。
    Color blindness is a retinal disease that mainly manifests as a color vision disorder, characterized by achromatopsia, red-green color blindness, and blue-yellow color blindness. With the development of technology and progress in theory, extensive research has been conducted on the genetic basis of color blindness, and various approaches have been explored for its treatment. This article aims to provide a comprehensive review of recent advances in understanding the pathological mechanism, clinical symptoms, and treatment options for color blindness. Additionally, we discuss the various treatment approaches that have been developed to address color blindness, including gene therapy, pharmacological interventions, and visual aids. Furthermore, we highlight the promising results from clinical trials of these treatments, as well as the ongoing challenges that must be addressed to achieve effective and long-lasting therapeutic outcomes. Overall, this review provides valuable insights into the current state of research on color blindness, with the intention of informing further investigation and development of effective treatments for this disease.
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  • 文章类型: Case Reports
    失败的原发性全膝关节置换术在年轻人中变得越来越普遍,更活跃的患者人口统计。无菌性失败伴胫骨近端骨丢失,特别是严重的胫骨后塌陷,是文献中没有很好描述的难题。在提供足够的结构支撑的同时适当恢复坡度的重建胫骨近端大缺损的选择有限。据我们所知,这种技术来解决一个大的,未包含的胫骨近端后部缺损在文献中没有描述。此病例报告的目的是详细说明手术技术,即如何使用胶结技术实施圆锥技术为患有此难题的患者带来了出色的临床效果。
    Failed primary total knee arthroplasties are becoming more common among a younger, more active patient demographic. Aseptic failures with proximal tibial bone loss, specifically severe posterior tibial collapse, are difficult problems not well described in the literature. There are limited options for reconstructing large defects of the proximal tibia that appropriately restore slope while providing adequate structural support. To our knowledge, this technique to address a large, uncontained posterior proximal tibial defect has not been described in the literature. The purpose of this case report was to detail the surgical technique of how the implementation of cone technology with cementation techniques produced excellent clinical results for a patient with this difficult problem.
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  • 文章类型: Journal Article
    描述接受Ebstein异常(EA)和三尖瓣发育不良(TVD)手术的新生儿和婴儿的手术结果。
    回顾性图表回顾了2005年1月至2023年2月在我们机构出生后的索引住院期间接受EA或TVD手术的所有患者。
    包括15例有症状的新生儿和接受EA或TVD手术的婴儿,8与EA和7与TVD。11例患者(73%)和3例患者(20%)需要术前收缩和体外膜氧合,分别。9名患者(60%)进行了Starnes手术,6名患者(40%)进行了三尖瓣修复(TVr)。上次随访时的死亡率为27%(n=4/15),Starnes后22%(n=2/9)和TVr后33%(n=2/6),尽管Starnes组的风险更大,但没有显着差异。术后第1天乳酸水平与Cox回归死亡率相关(风险比,1.45;P=0.01)。接受Starnes手术的9例患者中有3例已经或将要接受视锥修复(1.5/2心室修复)。
    在出生后住院期间,EA或TVD手术后的死亡率在当前时代仍然很重要,并且与术后第1天更高的乳酸水平相关。尽管Starnes组的风险更大,但Starnes程序和TVr具有可比的结果。最初的单心室方法并不排除转换为双心室或1.5心室修复。
    UNASSIGNED: To describe the surgical outcomes in neonates and infants who had surgery for Ebstein anomaly (EA) and tricuspid valve dysplasia (TVD).
    UNASSIGNED: Retrospective chart review for all patients who underwent surgery for EA or TVD during the index hospitalization after birth at our institution from January 2005 to February 2023.
    UNASSIGNED: Fifteen symptomatic neonates and infants who had surgery for EA or TVD were included, 8 with EA and 7 with TVD. Eleven patients (73%) and 3 patients (20%) required preoperative inotropes and extracorporeal membrane oxygenation, respectively. Nine patients (60%) had a Starnes procedure and 6 patients (40%) had tricuspid valve repair (TVr). Mortality at last follow-up was 27% overall (n = 4/15), 22% after Starnes (n = 2/9) and 33% after TVr (n = 2/6), without a significant difference despite a greater-risk profile in the Starnes group. Postoperative day 1 lactate level was associated with mortality on Cox regression (hazard ratio, 1.45; P = .01). Three of 9 patients who had a Starnes procedure were or will be converted to a cone repair (1.5/2-ventricle repair).
    UNASSIGNED: Mortality after surgery for EA or TVD during the index hospitalization after birth is still significant in the current era and is associated with a greater lactate level at postoperative day 1. The Starnes procedure and TVr had comparable outcomes despite a greater-risk profile in the Starnes group. An initial single-ventricle approach does not preclude conversion to biventricular or 1.5-ventricle repair.
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  • 文章类型: Journal Article
    所有翻修全膝关节置换术中都存在骨丢失。干phy端锥允许外科医生在获得稳定的骨固定的同时协商股骨和胫骨骨的丢失。这项研究检查了使用新型干phy端锥系统进行翻修全膝关节置换术(rTKA)的患者的中期功能和影像学结果。
    这项多中心回顾性研究检查了所有接受多孔,钛胫骨或股骨锥在四个学术城市三级护理机构,并提出了至少两年的随访。患者人口统计学,修正手术的适应症,膝关节运动范围(ROM),重新修订率,射线照相测量,根据AORI分类的骨缺损,根据膝关节协会全膝关节置换术(TKA)的影像学评估系统评估和植入物骨整合。
    104名患者接受了128个锥形植入物(84个胫骨,44个股骨锥;24例同时出现同侧胫骨和股骨锥;104rTKA),平均随访32.75±6.54个月。术前主要修正指征为无菌性松动36例(34.61%),假体周围感染(PJI)23(22.11%)和不稳定18(17.3%)。13例rTKA接受了重新翻修手术:3例急性PJI,4为慢性PJI,5不稳定,和1铰链系统的机械故障。在最近的射线照相随访中,所有未修正的视锥细胞均有骨整合的证据,且无可见的植入物迁移.全因再手术无生存率为87.5%(91/104),在2年的随访中,全因圆锥植入物的生存率为96.09%(123/128圆锥)。
    这项研究证明了一种新型多孔,在接受复杂翻修TKA的大型骨缺损患者中,钛干phy端锥。
    IV,案例系列。
    UNASSIGNED: Bone loss is present in all revision total knee arthroplasties. Metaphyseal cones allow surgeons to negotiate loss of femoral and tibial bone stock while obtaining stable bony fixation. This study examines the mid-term functional and radiographic outcomes in patients undergoing revision total knee arthroplasty (rTKA) utilizing a novel metaphyseal cone system.
    UNASSIGNED: This multicenter retrospective study examined all patients who received a porous, titanium tibial or femoral cone at four academic urban tertiary care institutions and presented for a minimum two-year follow-up. Patient demographics, indications for revision surgery, knee range-of-motion (ROM), re-revision rates, radiographic measurements, bone defect per AORI classification, and implant osseointegration were evaluated according to the Knee Society total knee arthroplasty (TKA) radiographic evaluation system.
    UNASSIGNED: One-hundred and four patients received 128 cone implants (84 tibial, 44 femoral cones; 24 patients with simultaneous ipsilateral tibial and femoral cones; 104 rTKA) with mean follow-up of 32.75 ± 6.54 months. The pre-operative main revision indications were aseptic loosening 36 (34.61 %), periprosthetic infection (PJI) 23 (22.11 %) and instability 18 (17.3 %). Thirteen rTKA underwent re-revision surgery: 3 for acute PJI, 4 for chronic PJI, 5 for instability, and 1 for mechanical failure of a hinged system. At most recent radiographic follow-up available, all unrevised cones had evidence of osteointegration and no visible implant migration.All-cause re-operation free survivorship was 87.5 % (91/104), and all-cause cone implant survivorship was 96.09 % (123/128 cones) at 2-year follow-up.
    UNASSIGNED: This study demonstrates excellent mid-term outcomes of a novel porous, titanium metaphyseal cone in patients with large bone defects undergoing complex revision TKA.
    UNASSIGNED: IV, case series.
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  • 文章类型: Journal Article
    本文的重点是研究三元混合纳米流体的流动,特别是Al2O3-Cu-CNT/水混合物,具有浮力效应,跨越三个不同的几何形状:楔形,一个平板,还有一个圆锥体.该研究考虑了二次热辐射和非均匀性热源/散热器的存在。为了开发模型,卡塔尼奥-赫里斯托夫理论被利用。通过应用相似性变换并使用“MATLAB中的bvp4c函数”进行数值分析和求解,可以求解控制流的方程。由于模型和所涉及的方法固有的复杂形式,进行参数研究的常规方法在得出重要结论时经常面临挑战。为了解决上述问题,本文探讨了机器学习方法的潜力,以预见由多个相互关联的参数特征的流的行为。通过利用模拟数据,使用Levenberg-Marquardt算法训练人工神经网络,以学习和理解基础模式。随后,训练后的神经网络用于估计所有三个几何表面上的努塞尔数。这种方法提供了一个有希望的替代传统的参数研究,能够对复杂系统的行为进行更精确的预测和洞察。对于圆锥体上的THNF流,努塞尔数最高。ANN算法的均方误差(MSE)值,在所有分析的案例中,范围从0到0.03972。这些发现有助于更好地理解各种几何形状中三元混合纳米流体流动的特性和动力学,协助设计和优化涉及此类流体的传热系统。
    The focus of this paper revolves around the examination of flow of ternary hybrid nanofluid, specifically the Al2O3-Cu-CNT/water mixture, with buoyancy effect, across three distinct geometries: a wedge, a flat plate, and a cone. The study takes into account the presence of quadratic thermal radiation and heat source/sink of non-uniform nature. To develop the model, the Cattaneo-Christov theory is utilized. The equations governing the flow are solved by applying similarity transformations and employing the \"bvp4c function in MATLAB\" for numerical analysis and solution. Conventional methods for conducting parametric studies often face challenges in producing significant conclusions owing to the inherent complex form of the model and the method involved. To address the aforementioned issue, this paper explores the potential of machine learning methods to foresee the conduct of the flow characterized by multiple interconnected parameters. By utilizing simulated data, an artificial neural network is trained using the Levenberg-Marquardt algorithm to learn and comprehend the underlying patterns. Subsequently, the trained neural network is employed to estimate the Nusselt number on the surfaces of all three geometries. This approach offers a promising alternative to traditional parametric studies, enabling more precise predictions and insights into the behavior of complex systems. The Nusselt number is highest for THNF flow over the cone. The mean squared error (MSE) values for the ANN algorithm, across all analyzed cases, range from 0 to 0.03972. The findings contribute to an improved understanding of the characteristics and dynamics of ternary hybrid nanofluid flow in various geometries, assisting in the design and optimization of heat transfer systems involving such fluids.
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  • 文章类型: Systematic Review
    目的:探讨术前锥切术在宫颈癌中的作用,探讨其潜在的临床意义。
    方法:Cochrane图书馆,EMBASE,PubMed和WebofScience,截至2023年4月28日。
    方法:(1)观察性队列研究(2)比较早期宫颈癌患者的根治性子宫切除术和术前锥切术与非术前锥切术的研究,和(3)比较无病生存结果的研究。制表,整合和结果两个评审员独立地提取数据并评估研究的质量。荟萃分析采用联合风险比(HR)及其相应的95%置信区间(CI)来比较根治性子宫切除术与术前锥形切除术(CO)和未术前锥形切除术(NCO)的根治性子宫切除术。我们使用马尔可夫链蒙特卡罗(MCMC)方法进行了贝叶斯网络荟萃分析,以比较:1.微创根治性子宫切除术与术前锥切(MC)和2。开腹根治性子宫切除术与术前锥切(OC)和3。无术前锥切的微创根治性子宫切除术(MNC)和4。开腹根治性子宫切除术,未术前锥切(ONC)。
    结果:我们的研究包括15个回顾性试验,其中10个用于传统的成对荟萃分析,8个用于网络荟萃分析。未术前锥切的根治性子宫切除术组的癌症复发概率明显高于术前锥切的根治性子宫切除术组(HR0.52,95%CI0.41-0.65)。在网络荟萃分析中,没有术前锥切术的微创根治性子宫切除术显示出最差的生存结局.
    结论:术前锥形化似乎是降低复发风险的保护因素,协助临床医生预测早期宫颈癌患者的生存结果。它可能有助于在临床实践中为微创手术选择合适的候选人。
    OBJECTIVE: The investigation of the role of preoperative conization in cervical cancer aiming to explore its potential clinical significance.
    METHODS: Cochrane Library, Embase, PubMed, and Web of Science, up to April 28, 2023.
    METHODS: (1) Observational cohort studies, (2) studies comparing radical hysterectomy with preoperative conization (CO) vs radical hysterectomy without preoperative conization (NCO) in patients with early-stage cervical cancer, and (3) studies comparing disease-free survival outcomes.
    RESULTS: Two reviewers independently extracted the data and assessed the quality of the studies. The meta-analysis used combined hazard ratios along with their corresponding 95% confidence intervals to compare CO and NCO. We conducted a Bayesian network meta-analysis using Markov chain Monte Carlo methods to compare minimally invasive CO, open CO, minimally invasive NCO, and open NCO. Our study included 15 retrospective trials, 10 of which were used to traditional pairwise meta-analysis and 8 for network meta-analysis. The NCO group exhibited a notably higher probability of cancer recurrence than the CO group (hazard ratio, 0.52; 95% confidence interval, 0.41-0.65). In the network meta-analysis, minimally invasive NCO showed the worst survival outcome.
    CONCLUSIONS: Preoperative conization seems to be a protective factor in decreasing recurrence risk, assisting clinicians in predicting survival outcomes for patients with early-stage cervical cancer. It may potentially aid in selecting suitable candidates for minimally invasive surgery in clinical practice.
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