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Cerebral regional and network characteristics in asthma patients: a resting-state fMRI study

Siyi Li, Peilin Lv, Min He, Wenjing Zhang, Jieke Liu, Yao Gong, Ting Wang, Qiyong Gong, Yulin Ji, Su Lui

《医学前沿（英文）》 2020年 第14卷 第6期   页码 792-801 doi: 10.1007/s11684-020-0745-1

摘要： Asthma is a serious health problem that involves not only the respiratory system but also the central nervous system. Previous studies identified either regional or network alterations in patients with asthma, but inconsistent results were obtained. A key question remains unclear: are the regional and neural network deficits related or are they two independent characteristics in asthma? Answering this question is the aim of this study. By collecting resting-state functional magnetic resonance imaging from 39 patients with asthma and 40 matched health controls, brain functional measures including regional activity (amplitude of low-frequency fluctuations) and neural network function (degree centrality (DC) and functional connectivity) were calculated to systematically characterize the functional alterations. Patients exhibited regional abnormities in the left angular gyrus, right precuneus, and inferior temporal gyrus within the default mode network. Network abnormalities involved both the sensorimotor network and visual network with key regions including the superior frontal gyrus and occipital lobes. Altered DC in the lingual gyrus was correlated with the degree of airway obstruction. This study elucidated different patterns of regional and network changes, thereby suggesting that the two parameters reflect different brain characteristics of asthma. These findings provide evidence for further understanding the potential cerebral alterations in the pathophysiology of asthma.

关键词： asthma     brain     regional activation     functional connectivity     resting-state fMRI    

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Ultimate bearing capacity of strip footing resting on clay soil mixed with tire-derived aggregates

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 1016-1024 doi: 10.1007/s11709-021-0751-7

摘要： This study investigated the use of recycled tire-derived aggregate (TDA) mixed with kaolin as a method of increasing the ultimate bearing capacity ( UBC) of a strip footing. Thirteen 1g physical modeling tests were prepared in a rigid box of 0.6 m × 0.9 m in plan and 0.6 m in height. During sample preparation, 0%, 20%, 40%, or 60% (by weight) of powdery, shredded, small-sized granular (G 1–4 mm) or large-sized granular (G 5–8 mm) TDA was mixed with the kaolin. A strip footing was then placed on the stabilized kaolin and was caused to fail under stress-controlled conditions to determine the UBC. A rigorous 3D finite element analysis was developed in Optum G-3 to determine the UBC values based on the experimental test results. The experimental results showed that, except for the 20% powdery TDA, the TDA showed an increase in the UBC of the strip footing. When kaolin mixed with 20% G (5–8 mm), the UBC showed a threefold increase over that for the unreinforced case. The test with 20% G (1–4 mm) recorded the highest subgrade modulus. It was observed that the UBC calculated using finite element modeling overestimated the experimental UBC by an average of 9%.

关键词： kaolin     physical modeling tests     stabilization     numerical modeling    

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Fundamental buckling of circular plates with elastically restrained edges and resting on concentric rigid

Lokavarapu Bhaskara Rao, Chellapilla Kameswara Rao

《机械工程前沿（英文）》 2013年 第8卷 第3期   页码 291-297 doi: 10.1007/s11465-013-0255-9

摘要：

This work presents the existence of buckling mode switching with respect to the radius of concentric rigid ring support. The buckling mode may not be axisymmetric as previously assumed. In general, the plate may buckle in an axisymmetric mode but when the radius of the ring support becomes small, the plate may buckle in an asymmetric mode. The optimum radius of the concentric rigid ring support for maximum buckling load is also determined. Introducing internal rigid ring support, when placed at an optimal position increases the elastic buckling load capacity by 149.39 percent. The numerical results obtained are in good agreement with the previously published data.

关键词： buckling     circular plate     elastically restrained edge     rigid ring support     mode switching    

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Semi-analytical approach for free vibration analysis of cracked beams resting on two-parameter elastic

null

《机械工程前沿（英文）》 2014年 第9卷 第2期   页码 191-202 doi: 10.1007/s11465-014-0293-y

摘要：

In present study, free vibration of cracked beams resting on two-parameter elastic foundation with elastically restrained ends is considered. Euler-Bernoulli beam hypothesis has been applied and translational and rotational elastic springs in each end considered as support. The crack is modeled as a mass-less rotational spring which divides beam into two segments. After governing the equations of motion, the differential transform method (DTM) has been served to determine dimensionless frequencies and normalized mode shapes. DTM is a semi-analytical approach based on Taylor expansion series that converts differential equations to recursive algebraic equations. The DTM results for the natural frequencies in special cases are in very good agreement with results reported by well-known references. Also, the DTM procedure yields rapid convergence beside high accuracy without any frequency missing. Comprehensive studies to analyze the effects of crack location, crack severity, parameters of elastic foundation and boundary conditions on dimensionless frequencies as well as effects of elastic boundary conditions on cracked beams mode shapes are carried out and some problems handled for first time in this paper. Since this paper deals with general problem, the derived formulation has capability for analyzing free vibration of cracked beam with every boundary condition.

关键词： free vibration     cracked beam     elastic foundation     restrained ends     differential transform method    

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Discovery of the mechanisms of acupuncture in the treatment of migraine based on functional magnetic resonance imaging and omics

《医学前沿（英文）》   页码 993-1005 doi: 10.1007/s11684-023-0989-7

摘要： Migraine is one of the most prevalent and disabling neurological disease, but the current pharmacotherapies show limited efficacy and often accompanied by adverse effects. Acupuncture is a promising complementary therapy, but further clinical evidence is needed. The influence of acupuncture on migraine is not an immediate effect, and its mechanism remains unclear. This study aims to provide further clinical evidence for the anti-migraine effects of acupuncture and explore the mechanism involved. A randomized controlled trial was performed among 10 normal controls and 38 migraineurs. The migraineurs were divided into blank control, sham acupuncture, and acupuncture groups. Patients were subjected to two courses of treatment, and each treatment lasted for 5 days, with an interval of 1 day between the two courses. The effectiveness of treatment was evaluated using pain questionnaire. The functional magnetic resonance imaging (fMRI) data were analyzed for investigating brain changes induced by treatments. Blood plasma was collected for metabolomics and proteomics studies. Correlation and mediation analyses were performed to investigate the interaction between clinical, fMRI and omics changes. Results showed that acupuncture effectively relieved migraine symptoms in a way different from sham acupuncture in terms of curative effect, affected brain regions, and signaling pathways. The anti-migraine mechanism involves a complex network related to the regulation of the response to hypoxic stress, reversal of brain energy imbalance, and regulation of inflammation. The brain regions of migraineurs affected by acupuncture include the lingual gyrus, default mode network, and cerebellum. The effect of acupuncture on patients’ metabolites/proteins may precede that of the brain.

关键词： acupuncture     migraine     fMRI     metabolome     proteome    

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Advances in tissue state recognition in spinal surgery: a review

Hao Qu, Yu Zhao

《医学前沿（英文）》 2021年 第15卷 第4期   页码 575-584 doi: 10.1007/s11684-020-0816-3

摘要： Spinal disease is an important cause of cervical discomfort, low back pain, radiating pain in the limbs, and neurogenic intermittent claudication, and its incidence is increasing annually. From the etiological viewpoint, these symptoms are directly caused by the compression of the spinal cord, nerve roots, and blood vessels and are most effectively treated with surgery. Spinal surgeries are primarily performed using two different techniques: spinal canal decompression and internal fixation. In the past, tactile sensation was the primary method used by surgeons to understand the state of the tissue within the operating area. However, this method has several disadvantages because of its subjectivity. Therefore, it has become the focus of spinal surgery research so as to strengthen the objectivity of tissue state recognition, improve the accuracy of safe area location, and avoid surgical injury to tissues. Aside from traditional imaging methods, surgical sensing techniques based on force, bioelectrical impedance, and other methods have been gradually developed and tested in the clinical setting. This article reviews the progress of different tissue state recognition methods in spinal surgery and summarizes their advantages and disadvantages.

关键词： spinal surgery     tissue state recognition     image     force sensing     bioelectrical impedance    

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Effectiveness of state incentives for promoting wind energy: A panel data examination

Deepak SANGROYA,Jogendra NAYAK

《能源前沿（英文）》 2015年 第9卷 第3期   页码 247-258 doi: 10.1007/s11708-015-0364-8

摘要： Over the last decade, India has started to concentrate earnestly on renewable energy. The Indian government, as well as different state governments, are adopting policy instruments such as feed in tariff, captive consumption, renewable purchase obligation and generation based incentive etc. aimed at renewable energy development. This paper evaluates the effectiveness of state level incentives for the development of wind energy in India. Fixed effect panel data modelling technique of econometric analysis is used to analyse the data of 26 Indian states in 11 years. The results show that feed in tariff and captive consumption are the significant predictors of wind energy development. However, renewable purchase obligation does not affect wind energy significantly.

关键词： India     wind energy development     state incentives     econometric analysis     panel data    

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Digital image correlation-based structural state detection through deep learning

《结构与土木工程前沿（英文）》 2022年 第16卷 第1期   页码 45-56 doi: 10.1007/s11709-021-0777-x

摘要： This paper presents a new approach for automatical classification of structural state through deep learning. In this work, a Convolutional Neural Network (CNN) was designed to fuse both the feature extraction and classification blocks into an intelligent and compact learning system and detect the structural state of a steel frame; the input was a series of vibration signals, and the output was a structural state. The digital image correlation (DIC) technology was utilized to collect vibration information of an actual steel frame, and subsequently, the raw signals, without further pre-processing, were directly utilized as the CNN samples. The results show that CNN can achieve 99% classification accuracy for the research model. Besides, compared with the backpropagation neural network (BPNN), the CNN had an accuracy similar to that of the BPNN, but it only consumes 19% of the training time. The outputs of the convolution and pooling layers were visually displayed and discussed as well. It is demonstrated that: 1) the CNN can extract the structural state information from the vibration signals and classify them; 2) the detection and computational performance of the CNN for the incomplete data are better than that of the BPNN; 3) the CNN has better anti-noise ability.

关键词： structural state detection     deep learning     digital image correlation     vibration signal     steel frame    

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Biological pretreatment of corn stover by solid state fermentation of

Jian ZHANG, Xin REN, Wenqun CHEN, Jie BAO

《化学科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 146-151 doi: 10.1007/s11705-012-1220-6

摘要： Biological pretreatment is a promising way to overcome the biorecalcitrance of cleaving the supermolecular structure of lignocellulose by lignin degrading enzymes from microorganisms. Solid state fermentation of corn stover with the white-rot fungus was carried out and the efficiency of this pretreatment was evaluated. The enzymatic hydrolysis yield reached a maximum when the corn stover was biologically pretreated for nine days, and the hydrolysis yield decreased sharply if the solid state fermentation was carried out for more than nine days. A possible explanation for this sharp decrease is that not only the lignin degrading enzymes (LiP and MnP) were secreted, but also other metabolites, which were toxic or fatal to the hydrolysis enzymes resulting in the lower hydrolysis yield were generated during the prolonged period of biopretreatment. These results are useful to help determine the optimal timing and to understand the lignin structure and degradation mechanism in biological pretreatment processes.

关键词： biological pretreatment     Phanerochaete chrysosporium     solid state fermentation     biorecalcitrance     hydrolysis yield    

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Development of a constitutive model for rockfills and similar granular materials based on the disturbed state

Mehdi VEISKARAMI, Ali GHORBANI, Mohammadreza ALAVIPOUR

《结构与土木工程前沿（英文）》 2012年 第6卷 第4期   页码 365-378 doi: 10.1007/s11709-012-0178-2

摘要： Behavior of rockfills was investigated experimentally and theoretically. A series of standard triaxial compression tests were carried out on a quarried rockfill material at different stress levels. It was found that both the stress level and the shear stress ratio, like most of granular materials, controls the behavior of rockfill materials. At lower shear stress ratios the behavior is much more similar to a nonlinear elastic solid. When the shear stress goes further, the stress-strain curve shows an elasto-plastic behavior which suggests using the disturbed state concept to develop a constitutive model to predict the stress-strain behavior. The presented constitutive model complies reasonably with the experimental data.

关键词： constitutive model     granular material     rockfill     plasticity     disturbed state concept     stress level    

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Machine learning and neural network supported state of health simulation and forecasting model for lithium-ion

《能源前沿（英文）》 doi: 10.1007/s11708-023-0891-7

摘要： As the intersection of disciplines deepens, the field of battery modeling is increasingly employing various artificial intelligence (AI) approaches to improve the efficiency of battery management and enhance the stability and reliability of battery operation. This paper reviews the value of AI methods in lithium-ion battery health management and in particular analyses the application of machine learning (ML), one of the many branches of AI, to lithium-ion battery state of health (SOH), focusing on the advantages and strengths of neural network (NN) methods in ML for lithium-ion battery SOH simulation and prediction. NN is one of the important branches of ML, in which the application of NNs such as backpropagation NN, convolutional NN, and long short-term memory NN in SOH estimation of lithium-ion batteries has received wide attention. Reports so far have shown that the utilization of NN to model the SOH of lithium-ion batteries has the advantages of high efficiency, low energy consumption, high robustness, and scalable models. In the future, NN can make a greater contribution to lithium-ion battery management by, first, utilizing more field data to play a more practical role in health feature screening and model building, and second, by enhancing the intelligent screening and combination of battery parameters to characterize the actual lithium-ion battery SOH to a greater extent. The in-depth application of NN in lithium-ion battery SOH will certainly further enhance the science, reliability, stability, and robustness of lithium-ion battery management.

关键词： machine learning     lithium-ion battery     state of health     neural network     artificial intelligence    

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Firm Innovation Systems: Perspectives of Researches on State-owned Key Enterprises

Jin Chen,Shu-fang Huang,Qing-rui Xu

《工程管理前沿（英文）》 2015年 第2卷 第1期   页码 64-70 doi: 10.15302/J-FEM-2015017

摘要： Based on the origin of the innovation theory and the technological innovation models of Rothwell, this paper puts forward four-generations of evolutionary models using the firm innovation system: “Internal R&D-Oriented Innovation System”, “Internal and External Collaborative Innovation System”, “Highly Strategic-Oriented Innovation System” and “Ecological Innovation System”. This paper dwells on the characteristics and relationship between each innovation system, and the role in the enterprise innovation especially the State-owned Key Enterprises innovation, so as to provide a theoretical and practical basis for the design and improvement of the State-owned Key Enterprises innovation system.

关键词： firm innovation system     state-owned key enterprises     ecology     evolution    

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Modeling and analysis of steady-state vibration induced by backlash in servo rotary table

Xiao YANG,Dun LU,Sanli LIU,Jun ZHANG,Wanhua ZHAO

《机械工程前沿（英文）》 2015年 第10卷 第1期   页码 43-47 doi: 10.1007/s11465-015-0327-0

摘要：

Backlash cannot be always avoided in mechanical systems because of wear or looseness. Steady-state vibration may be induced by backlash in closed loop feed drive systems. This paper presents a mathematical model of a servo rotary table, considering the effect of backlash. The accuracy of this model is verified by an experiment. The influences of the parameters, such as position controller gain, velocity controller gain, load and the magnitude of backlash, on steady-state vibration are discussed. The steady-state vibration amplitude increases with the position controller gain, load and the magnitude of backlash. The steady-state vibration frequency increases with the position controller gain and the velocity controller gain, while an increase in load leads to a decrease in the frequency.

关键词： backlash     servo rotary table     steady-state vibration    

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Assessment of robustness of structures: Current state of research

Colin BRETT, Yong LU

《结构与土木工程前沿（英文）》 2013年 第7卷 第4期   页码 356-368 doi: 10.1007/s11709-013-0220-z

摘要： The concept of structural robustness and relevant design guidelines have been in existence in the progressive collapse literature since the 1970s following the partial collapse of the Ronan Point apartment building; however, in the more general context, research on the evaluation and enhancement of structural robustness is still relatively limited. This paper is aimed to provide a general overview of the current state of research concerning structural robustness. The focus is placed on the quantification and the associated evaluation methodologies, rather than specific measures to ensure prescriptive robustness requirements. Some associated concepts, such as redundancy and vulnerability, will be discussed and interpreted in the general context of robustness such that the corresponding methodologies can be compared quantitatively using a comparable scale. A framework methodology proposed by the authors is also introduced in line with the discussion of the literature.

关键词： structural robustness     abnormal exposure     vulnerability     collapse     consequence    

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Application of Fe(VI) in abating contaminants in water: State of art and knowledge gaps

《环境科学与工程前沿（英文）》 2021年 第15卷 第5期 doi: 10.1007/s11783-020-1373-3

摘要：

• The properties of Fe(VI) were summarized.

关键词： Ferrate     Oxidation     Disinfection     Coagulation     Enhancement    

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标题 作者 时间 类型 操作

Cerebral regional and network characteristics in asthma patients: a resting-state fMRI study

Siyi Li, Peilin Lv, Min He, Wenjing Zhang, Jieke Liu, Yao Gong, Ting Wang, Qiyong Gong, Yulin Ji, Su Lui

期刊论文

Ultimate bearing capacity of strip footing resting on clay soil mixed with tire-derived aggregates

期刊论文

Fundamental buckling of circular plates with elastically restrained edges and resting on concentric rigid

Lokavarapu Bhaskara Rao, Chellapilla Kameswara Rao

期刊论文

Semi-analytical approach for free vibration analysis of cracked beams resting on two-parameter elastic

null

期刊论文

Discovery of the mechanisms of acupuncture in the treatment of migraine based on functional magnetic resonance imaging and omics

期刊论文

Advances in tissue state recognition in spinal surgery: a review

Hao Qu, Yu Zhao

期刊论文

Effectiveness of state incentives for promoting wind energy: A panel data examination

Deepak SANGROYA,Jogendra NAYAK

期刊论文

Digital image correlation-based structural state detection through deep learning

期刊论文

Biological pretreatment of corn stover by solid state fermentation of

Jian ZHANG, Xin REN, Wenqun CHEN, Jie BAO

期刊论文

Development of a constitutive model for rockfills and similar granular materials based on the disturbed state

Mehdi VEISKARAMI, Ali GHORBANI, Mohammadreza ALAVIPOUR

期刊论文

Machine learning and neural network supported state of health simulation and forecasting model for lithium-ion

期刊论文

Firm Innovation Systems: Perspectives of Researches on State-owned Key Enterprises

Jin Chen,Shu-fang Huang,Qing-rui Xu

期刊论文

Modeling and analysis of steady-state vibration induced by backlash in servo rotary table

Xiao YANG,Dun LU,Sanli LIU,Jun ZHANG,Wanhua ZHAO

期刊论文

Assessment of robustness of structures: Current state of research

Colin BRETT, Yong LU

期刊论文

Application of Fe(VI) in abating contaminants in water: State of art and knowledge gaps

期刊论文