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Role of salivary matrix metalloproteinase-8 (MMP-8) in chronic periodontitis diagnosis

null

《医学前沿（英文）》 2015年 第9卷 第1期   页码 72-76 doi: 10.1007/s11684-014-0347-x

摘要：

Periodontitis is an inflammatory disease of the periodontium. Any imbalance between the matrix metalloproteinases (MMPs) secreted by neutrophils and tissue inhibitors initiates the destruction of collagen in gum tissue, leading to chronic periodontitis. This study aimed to correlate salivary levels of MMP-8 and periodontal parameters of chronic periodontitis to establish MMP-8 as a noninvasive marker for the early diagnosis of chronic periodontitis. The study involved 40 subjects visiting the periodontic OPD of Dr. Ziauddin Ahmad Dental College and Hospital, located in Aligarh, U.P., India, from 2011 to 2012. The subjects were divided into two groups: group I consisted of 20 periodontally healthy subjects (controls) while group II consisted of 20 patients with chronic periodontitis. Chronic periodontitis was assessed on the basis of several periodontal parameters, including pocket probing depth (PPD), clinical attachment level (CAL), gingival index (GI), and plaque index (PI). Around 3 ml of unstimulated and whole expectorated saliva was collected for MMP-8 estimation by ELISA using Quantikine human total MMP-8 immunoassay kits. Data were analyzed using STATISTICA (Windows version 6) software. Salivary MMP-8 levels of groups I and II were 190.91±143.89 ng/ml and 348.26±202.1 ng/ml, respectively. The MMP-8 levels and periodontal status (PPD, CAL, GI, and PI) of groups I and II showed positive and significant correlations (for PPD, r = 0.63, P<0.001; for CAL, r = 0.54, P<0.001; for GI, r = 0.49, P<0.001; and for PI, r = 0.63, P<0.001). The results of this study demonstrate elevated concentrations of MMP-8 in individuals with chronic periodontitis.

关键词： matrix metalloproteinase-8     chronic periodontitis     pocket probing depth     clinical attachment level     gingival index     plaque index    

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Learning from biological attachment devices: applications of bioinspired reversible adhesive methods

《机械工程前沿（英文）》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0699-x

摘要： Many organisms have attachment organs with excellent functions, such as adhesion, clinging, and grasping, as a result of biological evolution to adapt to complex living environments. From nanoscale to macroscale, each type of adhesive organ has its own underlying mechanisms. Many biological adhesive mechanisms have been studied and can be incorporated into robot designs. This paper presents a systematic review of reversible biological adhesive methods and the bioinspired attachment devices that can be used in robotics. The study discussed how biological adhesive methods, such as dry adhesion, wet adhesion, mechanical adhesion, and sub-ambient pressure adhesion, progress in research. The morphology of typical adhesive organs, as well as the corresponding attachment models, is highlighted. The current state of bioinspired attachment device design and fabrication is discussed. Then, the design principles of attachment devices are summarized in this article. The following section provides a systematic overview of climbing robots with bioinspired attachment devices. Finally, the current challenges and opportunities in bioinspired attachment research in robotics are discussed.

关键词： adhesion     bioinspired attachment     biomimetic gripper     climbing robot    

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Matrix attachment regions included in a bicistronic vector enhances and stabilizes follistatin gene expressions

Xiaoming HU,Jing GUO,Chunling BAI,Zhuying WEI,Li GAO,Tingmao HU,Shorgan BOU,Guangpeng LI

《农业科学与工程前沿（英文）》 2016年 第3卷 第1期   页码 87-96 doi: 10.15302/J-FASE-2016087

摘要： In the present study, follistatin ( ) gene expression vectors with either a bicistronic gene transfer cassette alone, or a bicistron gene cassette carrying a matrix attachment region (MAR) were constructed and transfected to bovine fetal fibroblasts. Evaluations of both the integration and expression of exogenous indicated that the pMAR-CAG-FST-IRES-AcGFP1-polyA-MAR (pMAR-FST) vector had higher capacity to form monoclonal transgenic cells than the vector without MAR, though transient transfection and integration efficiency were similar with either construct. Remarkably, protein expression in transgenic cells with the pMAR-FST vector was significantly higher than that from the bicistronic vector. Exogenous was expressed in all of the pMAR-FST transgenic mice at F , F and F . Total muscle growth in F mice was significantly greater than in wild-type mice, with larger muscles in fore and hind limbs of transgenic mice. pMAR-FST transgenic mice were also found with more evenly distributed muscle bundles and thinner spaces between sarcolemma, which suggests a correlation between transgene expression-associated muscle development and the trend of muscle growth. In conclusion, a pMAR-FST vector, which excluded the resistant genes and frame structure, enhances and stabilizes gene expressions in both transfected cells and transgenic mice.

关键词： safety of transgenic     bicistron gene transfer body     transgenic mice     muscle development    

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Transparent exopolymer particles (TEPs)-associated protobiofilm: A neglected contributor to biofouling during membrane filtration

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1361-7

摘要：

• Bacteria could easily and quickly attached onto TEP to form protobiofilms.

关键词： Transparent exopolymer particles (TEPs)     TEP-protobiofilm     Bacteria attachment     Biofouling of membrane    

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适应性贴附通风——负压呼吸性传染病隔离病房有效性的比较研究 Article

张莹, 韩欧, 李安桂, 侯立安, Thomas Olofsson, 张林华, 雷文君

《工程（英文）》 2022年 第8卷 第1期   页码 130-137 doi: 10.1016/j.eng.2020.10.020

摘要：

新型冠状病毒的传播给隔离病房的室内环境控制提出了挑战。科学的气流组织设计和运行管理是保证医护人员环境安全的关键。本文提出了适应性贴附通风在隔离病房的应用，并从污染物扩散、去除效率、热舒适性和运行费用等方面对这种送风方式进行了评估。适应性贴附通风将新鲜空气直接、较好地供应至医护人员工作区。与顶送风或侧壁上送风相比，在相同的污染物释放率和房间换气次数（ACH; 10 h-1）条件下，适应性贴附通风的污染物平均浓度降低了15% ~ 47%。理想的混合通风的污染物去除效率不能超过1.0。对于适应性贴附通风，污染物去除效率是换气次数的指数函数。与顶送风模式或侧壁上送风模式相比，适应性贴附通风可实现相似的热舒适水平[预测平均评价（PMV）为-0.1~0.4；吹风感为2.5%~6.7%]，且以较低的换气次数和能耗获得相似去除污染物的性能。

关键词： 通风效率     换气率     COVID-19     贴附通风     气流组织     隔离病房    

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Simulation of heterogeneous two-phase media using random fields and level sets

George STEFANOU

《结构与土木工程前沿（英文）》 2015年 第9卷 第2期   页码 114-120 doi: 10.1007/s11709-014-0267-5

摘要： The accurate and efficient simulation of random heterogeneous media is important in the framework of modeling and design of complex materials across multiple length scales. It is usually assumed that the morphology of a random microstructure can be described as a non-Gaussian random field that is completely defined by its multivariate distribution. A particular kind of non-Gaussian random fields with great practical importance is that of translation fields resulting from a simple memory-less transformation of an underlying Gaussian field with known second-order statistics. This paper provides a critical examination of existing random field models of heterogeneous two-phase media with emphasis on level-cut random fields which are a special case of translation fields. The case of random level sets, often used to represent the geometry of physical systems, is also examined. Two numerical examples are provided to illustrate the basic features of the different approaches.

关键词： microstructure     random fields     level sets     shape recovery     two-phase media    

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Ontological reconstruction of the clinical terminology of traditional Chinese medicine

null

《医学前沿（英文）》 2014年 第8卷 第3期   页码 358-361 doi: 10.1007/s11684-014-0348-9

摘要：

This study proposes the ontological reconstruction of the current clinical terminology of traditional Chinese medicine (TCM). It also provides an overview of preliminary work related to the said reconstruction, including the ontology-based analysis of TCM clinical terminology. We conclude that the ontological reconstruction of TCM clinical terminology provides a proper translation from the idealized organizational model to real-world implementation and to a formalized, shared, and knowledge-based framework.

关键词： ontology     traditional Chinese medicine     clinical terminology    

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The effect of sea level rise on beach morphology of caspian sea coast

M. A. Lashteh NESHAEI, F. GHANBARPOUR

《结构与土木工程前沿（英文）》 2017年 第11卷 第4期   页码 369-379 doi: 10.1007/s11709-017-0398-6

摘要： Study of beach morphology has been one of the most important issues in coastal engineering research projects. Because of the existence of two important coastal areas located in the north and south parts of the Iran, in the present study an analysis of the coastal zone behaviour is made. Bed level elevations are measured and compared with the theoretical equilibrium profile. It is shown that the behaviour of the coastal zone in the region is consistent with the Dean (1991) equilibrium profile. In the next stage, following extensive investigations, the bed level changes due to arise in sea level at different locations in the surf zone are estimated. The mechanism of beach re-treatment due to a rise in sea level is considered based on the simplified model of Dean (1991) in which the mass balance of the sediments is taken into account. Comparison of the equilibrium profiles for different cases of sea level rise, clearly shows that because of the sediment transport induced by the fluctuation of the water level, the beach profile in the surf zone changes accordingly resulting in an erosion in the inner region of the surf zone and an accumulation of sediments towards the offshore.

关键词： wave     coastal zone     beach morphology     evolution     equilibrium profile     sea level rise    

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Level set band method: A combination of density-based and level set methods for the topology optimization

Peng WEI, Wenwen WANG, Yang YANG, Michael Yu WANG

《机械工程前沿（英文）》 2020年 第15卷 第3期   页码 390-405 doi: 10.1007/s11465-020-0588-0

摘要： The level set method (LSM), which is transplanted from the computer graphics field, has been successfully introduced into the structural topology optimization field for about two decades, but it still has not been widely applied to practical engineering problems as density-based methods do. One of the reasons is that it acts as a boundary evolution algorithm, which is not as flexible as density-based methods at controlling topology changes. In this study, a level set band method is proposed to overcome this drawback in handling topology changes in the level set framework. This scheme is proposed to improve the continuity of objective and constraint functions by incorporating one parameter, namely, level set band, to seamlessly combine LSM and density-based method to utilize their advantages. The proposed method demonstrates a flexible topology change by applying a certain size of the level set band and can converge to a clear boundary representation methodology. The method is easy to implement for improving existing LSMs and does not require the introduction of penalization or filtering factors that are prone to numerical issues. Several 2D and 3D numerical examples of compliance minimization problems are studied to illustrate the effects of the proposed method.

关键词： level set method     topology optimization     density-based method     level set band    

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The clinical impact of tricuspid regurgitation in patients with a biatrial orthotopic heart transplant

《医学前沿（英文）》 2023年 第17卷 第3期   页码 527-533 doi: 10.1007/s11684-022-0967-5

摘要： In this study, we aim to elucidate the clinical impact and long-term course of tricuspid regurgitation (TR), taking into account its dynamic nature, after biatrial orthotopic heart transplant (OHT). All consecutive adult patients undergoing biatrial OHT (1984−2017) with an available follow-up echocardiogram were included. Mixed-models were used to model the evolution of TR. The mixed-model was inserted into a Cox model in order to address the association of the dynamic TR with mortality. In total, 572 patients were included (median age: 50 years, males: 74.9%). Approximately 32% of patients had moderate-to-severe TR immediately after surgery. However, this declined to 11% on 5 years and 9% on 10 years after surgery, adjusted for survival bias. Pre-implant mechanical support was associated with less TR during follow-up, whereas concurrent LV dysfunction was significantly associated with more TR during follow-up. Survival at 1, 5, 10, 20 years was 97% ± 1%, 88% ± 1%, 66% ± 2% and 23% ± 2%, respectively. The presence of moderate-to-severe TR during follow-up was associated with higher mortality (HR: 1.07, 95% CI (1.02–1.12), p = 0.006). The course of TR was positively correlated with the course of creatinine (R = 0.45). TR during follow-up is significantly associated with higher mortality and worse renal function. Nevertheless, probability of TR is the highest immediately after OHT and decreases thereafter. Therefore, it may be reasonable to refrain from surgical intervention for TR during earlier phase after OHT.

关键词： orthotopic heart transplant     tricuspid regurgitation     clinical impact     biatrial heart transplantation    

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Obesity-related glomerulopathy: pathogenesis, pathologic, clinical characteristics and treatment

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 340-348 doi: 10.1007/s11684-017-0570-3

摘要：

In light of the rapid increase in the number of obesity incidences worldwide, obesity has become an independent risk factor for chronic kidney disease. Obesity-related glomerulopathy (ORG) is characterized by glomerulomegaly in the presence or absence of focal and segmental glomerulosclerosis lesions. IgM and complement 3 (C3) nonspecifically deposit in lesions without immune-complex-type deposits during ORG immunofluorescence. ORG-associated glomerulomegaly and focal and segmental glomerulosclerosis can superimpose on other renal pathologies. The mechanisms under ORG are complex, especially hemodynamic changes, inflammation, oxidative stress, apoptosis, and reduced functioning nephrons. These mechanisms synergize with obesity to induce end-stage renal disease. A slow increase of subnephrotic proteinuria (<3.5 g/d) is the most common clinical manifestation of ORG. Several treatment methods for ORG have been developed. Of these methods, renin–angiotensin–aldosterone system blockade and weight loss are proven effective. Targeting mitochondria may offer a novel strategy for ORG therapy. Nevertheless, more research is needed to further understand ORG.

关键词： obesity-related glomerulopathy     pathogenesis     pathologic     clinical characteristics    

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Coronavirus disease 2019 (COVID-19): a clinical update

Min Zhou, Xinxin Zhang, Jieming Qu

《医学前沿（英文）》 2020年 第14卷 第2期   页码 126-135 doi: 10.1007/s11684-020-0767-8

摘要： Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has posed a significant threat to global health. It caused a total of 80 868 confirmed cases and 3101 deaths in Chinese mainland until March 8, 2020. This novel virus spread mainly through respiratory droplets and close contact. As disease progressed, a series of complications tend to develop, especially in critically ill patients. Pathological findings showed representative features of acute respiratory distress syndrome and involvement of multiple organs. Apart from supportive care, no specific treatment has been established for COVID-19. The efficacy of some promising antivirals, convalescent plasma transfusion, and tocilizumab needs to be investigated by ongoing clinical trials.

关键词： coronavirus disease 2019     epidemiology     pathology     radiology     clinical characteristics     treatment    

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钢塔节段水平预拼装关键技术研究

张永利,顾碧峰

《中国工程科学》 2010年 第12卷 第4期   页码 48-52

摘要：

通过对泰州长江公路大桥钢塔柱预拼装方案的选择和关键工艺的研究，提出结构形式复杂的钢塔节段预拼装工艺选择原则。在研究了钢塔节段预拼环境的影响、支撑条件、金属接触率等水平预拼装关键工艺控制项点后，成功地解决了泰州桥钢塔节段水平预拼装中的技术难题。钢塔节段水平预拼装填补了我国钢塔制造的技术空白，为后续复杂钢塔节段水平预拼装方案选择提供了有力基础。

关键词： 钢塔     水平预拼装     支撑控制     水平力施加    

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Hypertension in patients with CKD in China: clinical characteristics and management

null

《医学前沿（英文）》 2017年 第11卷 第3期   页码 307-309 doi: 10.1007/s11684-017-0578-8

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Two-level uncapacitated lot-sizing problem considering the financing cost of working capital requirement

Yuan BIAN, David LEMOINE, Thomas G. YEUNG, Nathalie BOSTEL

《工程管理前沿（英文）》 2020年 第7卷 第2期   页码 248-258 doi: 10.1007/s42524-019-0069-5

摘要： During financial crisis, companies constantly need free cash flows to efficiently react to any uncertainty, thus ensuring solvency. Working capital requirement (WCR) has been recognized as a key factor for releasing tied up cash in companies. However, in literatures related to lot-sizing problem, WCR has only been studied in the single-level supply chain context. In this paper, we initially adopt WCR model for a multi-level case. A two-level (supplier–customer) model is established on the basis of the classic multi-level lot-sizing model integrated with WCR financing cost. To tackle this problem, we propose sequential and centralized approaches to solve the two-level case with a serial chain structure. The ZIO (Zero Inventory Ordering) property is further confirmed valid in both cases. This property allows us to establish a dynamic programming-based algorithm, which solves the problem in O(T ). Finally, numerical tests show differences in optimal plans obtained by both approaches and the influence of varying delays in payment on the WCR of both actors.

关键词： two-level ULS problem     lot-sizing     working capital requirement     ZIO property     infinite production capacity    

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标题 作者 时间 类型 操作

Role of salivary matrix metalloproteinase-8 (MMP-8) in chronic periodontitis diagnosis

null

期刊论文

Learning from biological attachment devices: applications of bioinspired reversible adhesive methods

期刊论文

Matrix attachment regions included in a bicistronic vector enhances and stabilizes follistatin gene expressions

Xiaoming HU,Jing GUO,Chunling BAI,Zhuying WEI,Li GAO,Tingmao HU,Shorgan BOU,Guangpeng LI

期刊论文

Transparent exopolymer particles (TEPs)-associated protobiofilm: A neglected contributor to biofouling during membrane filtration

期刊论文

适应性贴附通风——负压呼吸性传染病隔离病房有效性的比较研究

张莹, 韩欧, 李安桂, 侯立安, Thomas Olofsson, 张林华, 雷文君

期刊论文

Simulation of heterogeneous two-phase media using random fields and level sets

George STEFANOU

期刊论文

Ontological reconstruction of the clinical terminology of traditional Chinese medicine

null

期刊论文

The effect of sea level rise on beach morphology of caspian sea coast

M. A. Lashteh NESHAEI, F. GHANBARPOUR

期刊论文

Level set band method: A combination of density-based and level set methods for the topology optimization

Peng WEI, Wenwen WANG, Yang YANG, Michael Yu WANG

期刊论文

The clinical impact of tricuspid regurgitation in patients with a biatrial orthotopic heart transplant

期刊论文

Obesity-related glomerulopathy: pathogenesis, pathologic, clinical characteristics and treatment

null

期刊论文

Coronavirus disease 2019 (COVID-19): a clinical update

Min Zhou, Xinxin Zhang, Jieming Qu

期刊论文

钢塔节段水平预拼装关键技术研究

张永利,顾碧峰

期刊论文

Hypertension in patients with CKD in China: clinical characteristics and management

null

期刊论文

Two-level uncapacitated lot-sizing problem considering the financing cost of working capital requirement

Yuan BIAN, David LEMOINE, Thomas G. YEUNG, Nathalie BOSTEL

期刊论文