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Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function
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作者 Xiang Ren Tan Mary C.Stephenson +4 位作者 Sharifah Badriyah Alhadad Kelvin W.Z.Loh Tuck Wah Soong Jason K.W.Lee Ivan C.C.Low 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期233-244,共12页
Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive function.While heat is a known physiological stressor,it is unclear how severe heat stres... Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive function.While heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and function.Methods:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm water immersion until their rectal temperatures(T_(re))attained 39.5℃,inducing exertional or passive hyperthermia,respectively.In a separate trial,blended ice was ingested before and during exercise as a cooling strategy.Data were compared to a control condition with seated rest(normothermic).Brain temperature(T_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging techniques.Results:T_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in T_(re).With the development of hyperthermia,T_(br)increases and dovetails with the rising T_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(T_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced with passive hyperthermia.Executive function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital cortex.Conversely,ingestion of blended ice before and during exercise alleviated the rise in both T_(re)and T_(bc)and mitigated heat-related neural perturbations.Conclusion:Severe heat exposure elevates T_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance. 展开更多
关键词 Brain functional activity COGNITION Heat stress HYPERTHERMIA Motor function
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Characterization and Functionalisation of Activated Carbon for the Enhancement of Enzyme Catalyst Activity
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作者 Nassereldeen A Kabbashi Yara Hunud Abia Kadouf +3 位作者 Ibrahim Adebayo Bello Elwathig M.Saeed Lubna Mohamed Musa Nassereldeen Ahmed Kabbashi 《材料科学与工程(中英文B版)》 2021年第2期81-87,共7页
Background and objective:Activated carbon is commonly used as an immobilisation matrix due to its large surface area,making it a highly desirable matrix for use in immobilising enzymes as preparation for use on the in... Background and objective:Activated carbon is commonly used as an immobilisation matrix due to its large surface area,making it a highly desirable matrix for use in immobilising enzymes as preparation for use on the industrial scale.The objective of this research is to determine the effectiveness of different acids for functionalisation on immobilisation capacity and also to characterize the functionalized activated carbon for the functional groups present.Materials and methods:Activated carbon was functionalised with three acids(hydrochloric acid,nitric acid and sulphuric acid)along with a control sample washed with distilled water.Immobilisation capacity was calculated with hydrochloric acid functionalized activated carbon(HCl-FAC)giving the highest immobilization capacity(6.022 U/g).Characterisation of the functionalised activated carbon was conducted using FT-IR(Fourier Transform Infra-Red)spectroscopy analysis of the samples with the aim of analyzing the various functional groups present to determine the sample with distinct characteristics thus telling the degree of adsorption of lipase onto the activated carbon powder.Results:HNO3-FAC(functionalized activated carbon)showed a very distinct pattern as a larger number of surface functional groups emerged.The immobilisation on a matrix ensures thermal stability and increased reusability of the enzyme.Therefore,in this research,lipase sourced from Candida antarctica was immobilised on acid functionalised activated carbon.The best acid for functionalisation was found to be hydrochloric acid.Conclusion:Due to the very distinct patterns shown by the FT-IR spectrum of the HNO3-FAC after a fair comparison with others,it allows for a larger number of surface functional groups which will definitely enhance the stability of the enzyme lipase. 展开更多
关键词 Activated carbon CHARACTERIZATION functionalized activated carbon enzyme activity
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Interpretation and characterization of rate of penetration intelligent prediction model
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作者 Zhi-Jun Pei Xian-Zhi Song +3 位作者 Hai-Tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期582-596,共15页
Accurate prediction of the rate of penetration(ROP)is significant for drilling optimization.While the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations... Accurate prediction of the rate of penetration(ROP)is significant for drilling optimization.While the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its credibility.This study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation function.By leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector operations.The FNN model is linearly characterized through further simplification,enabling its interpretation and analysis.The proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim Oilfield.The results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally well.The relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data similarity.In the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation equation.Furthermore,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well section.The established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections. 展开更多
关键词 Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning
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Uncertainty-Aware Physical Simulation of Neural Radiance Fields for Fluids
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作者 Haojie Lian Jiaqi Wang +4 位作者 Leilei Chen Shengze Li Ruochen Cao Qingyuan Hu Peiyun Zhao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期1143-1163,共21页
This paper presents a novel framework aimed at quantifying uncertainties associated with the 3D reconstruction of smoke from2Dimages.This approach reconstructs color and density fields from 2D images using Neural Radi... This paper presents a novel framework aimed at quantifying uncertainties associated with the 3D reconstruction of smoke from2Dimages.This approach reconstructs color and density fields from 2D images using Neural Radiance Field(NeRF)and improves image quality using frequency regularization.The NeRF model is obtained via joint training ofmultiple artificial neural networks,whereby the expectation and standard deviation of density fields and RGB values can be evaluated for each pixel.In addition,customized physics-informed neural network(PINN)with residual blocks and two-layer activation functions are utilized to input the density fields of the NeRF into Navier-Stokes equations and convection-diffusion equations to reconstruct the velocity field.The velocity uncertainties are also evaluated through ensemble learning.The effectiveness of the proposed algorithm is demonstrated through numerical examples.The presentmethod is an important step towards downstream tasks such as reliability analysis and robust optimization in engineering design. 展开更多
关键词 Uncertainty quantification neural radiance field physics-informed neural network frequency regularization twolayer activation function ensemble learning
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Nonparametric Statistical Feature Scaling Based Quadratic Regressive Convolution Deep Neural Network for Software Fault Prediction
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作者 Sureka Sivavelu Venkatesh Palanisamy 《Computers, Materials & Continua》 SCIE EI 2024年第3期3469-3487,共19页
The development of defect prediction plays a significant role in improving software quality. Such predictions are used to identify defective modules before the testing and to minimize the time and cost. The software w... The development of defect prediction plays a significant role in improving software quality. Such predictions are used to identify defective modules before the testing and to minimize the time and cost. The software with defects negatively impacts operational costs and finally affects customer satisfaction. Numerous approaches exist to predict software defects. However, the timely and accurate software bugs are the major challenging issues. To improve the timely and accurate software defect prediction, a novel technique called Nonparametric Statistical feature scaled QuAdratic regressive convolution Deep nEural Network (SQADEN) is introduced. The proposed SQADEN technique mainly includes two major processes namely metric or feature selection and classification. First, the SQADEN uses the nonparametric statistical Torgerson–Gower scaling technique for identifying the relevant software metrics by measuring the similarity using the dice coefficient. The feature selection process is used to minimize the time complexity of software fault prediction. With the selected metrics, software fault perdition with the help of the Quadratic Censored regressive convolution deep neural network-based classification. The deep learning classifier analyzes the training and testing samples using the contingency correlation coefficient. The softstep activation function is used to provide the final fault prediction results. To minimize the error, the Nelder–Mead method is applied to solve non-linear least-squares problems. Finally, accurate classification results with a minimum error are obtained at the output layer. Experimental evaluation is carried out with different quantitative metrics such as accuracy, precision, recall, F-measure, and time complexity. The analyzed results demonstrate the superior performance of our proposed SQADEN technique with maximum accuracy, sensitivity and specificity by 3%, 3%, 2% and 3% and minimum time and space by 13% and 15% when compared with the two state-of-the-art methods. 展开更多
关键词 Software defect prediction feature selection nonparametric statistical Torgerson-Gower scaling technique quadratic censored regressive convolution deep neural network softstep activation function nelder-mead method
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Effects of clump spacing on nutrient distribution and root activity of Dendrocalamus strictus in the humid region of Kerala,peninsular India 被引量:1
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作者 B. H. Kittur K. Sudhakara +2 位作者 B. Mohan Kumar T. K. Kunhamu P. Sureshkumar 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第6期1133-1144,共12页
The humid agroclimatic conditions of Kerala,India permit the cultivation of an array of bamboo species of which Dendrocalamus strictus Roxb.(Nees.) is an important one on account of its high growth rate and multiple u... The humid agroclimatic conditions of Kerala,India permit the cultivation of an array of bamboo species of which Dendrocalamus strictus Roxb.(Nees.) is an important one on account of its high growth rate and multiple uses. Stand density, a potential tool in controlling the productivity of woody ecosystems, its effect on growth and root distribution patterns may provide a better understanding of productivity optimization especially when bamboo-based intercropping options are considered.Growth attributes of 7-year-old bamboo(D. strictus) stands managed at variable spacing(4×4 m, 6×6 m, 8×8 m,10×10 m, 12×12 m) were studied. Functional root activity among bamboo clumps were also studied using a radio tracer soil injection method in which the radio isotopeP was applied to soil at varying depths and lateral distances from the clump. Results indicate that spacing exerts a profound influence on growth of bamboo. Widely spaced bamboo exhibited higher clump diameters and crown widths while clump heights were better under closer spacing. Clump height was 30% lower and DBH 52%higher at the widest spacing(12×12 m) compared to the closest spacing(4×4 m). With increasing soil depth and lateral distance, root activity decreased significantly. Root activity near the clump base was highest(809 counts per minute, cpm; 50 cm depth and 50 cm lateral distance) at 4×4 m. Tracer study further showed wider distribution of root activity with increase in clump spacing. It may be concluded that the intensive foraging zone of bamboo is within a 50-cm radius around the clump irrespective of spacing. N, P and K content in the upper 20 cm was 2197,21, and 203 kg/ha respectively for the closely spaced bamboo(4×4 m) which were significantly higher than corresponding nutrient content at wider spacings. About 50% of N, P and K were present within the 0–20 cm soil layer, which decreased drastically beyond the 20 cm depth.The results suggest that stand management practices through planting density regulation can modify the resource acquisition patterns of D. strictus which in turn can change growth and productivity considerably. Such information on root activities, spatial and temporal strategies of resource sharing will be helpful in deciding the effective nutrition zone for D. strictus. Further, the study throws light on the spatial distribution of non-competitive zones for productivity optimization yields, especially when intercropping practices are considered. 展开更多
关键词 BAMBOO Clump spacing functional root activity Radio tracer 32P Soil nutrients
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Microbial community structure and functional metabolic diversity are associated with organic carbon availability in an agricultural soil 被引量:5
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作者 LI Juan LI Yan-ting +3 位作者 YANG Xiang-dong ZHANG Jian-jun LIN Zhi-an ZHAO Bing-qiang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2500-2511,共12页
Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental ... Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental characteristics especially organic carbon availability after 15-yr different organic and inorganic fertilizer inputs on soil bacterial community structure and functional metabolic diversity of soil microbial communities were evaluated in a 15-yr fertilizer experiment in Changping County, Beijing, China. The experiment was a wheat-maize rotation system which was established in 1991 including four different fertilizer treatments. These treatments included: a non-amended control(CK), a commonly used application rate of inorganic fertilizer treatment(NPK); a commonly used application rate of inorganic fertilizer with swine manure incorporated treatment(NPKM), and a commonly used application rate of inorganic fertilizer with maize straw incorporated treatment(NPKS). Denaturing gradient gel electrophoresis(DGGE) of the 16 S r RNA gene was used to determine the bacterial community structure and single carbon source utilization profiles were determined to characterize the microbial community functional metabolic diversity of different fertilizer treatments using Biolog Eco plates. The results indicated that long-term fertilized treatments significantly increased soil bacterial community structure compared to CK. The use of inorganic fertilizer with organic amendments incorporated for long term(NPKM, NPKS) significantly promoted soil bacterial structure than the application of inorganic fertilizer only(NPK), and NPKM treatment was the most important driver for increases in the soil microbial community richness(S) and structural diversity(H). Overall utilization of carbon sources by soil microbial communities(average well color development, AWCD) and microbial substrate utilization diversity and evenness indices(H' and E) indicated that long-term inorganic fertilizer with organic amendments incorporated(NPKM, NPKS) could significantly stimulate soil microbial metabolic activity and functional diversity relative to CK, while no differences of them were found between NPKS and NPK treatments. Principal component analysis(PCA) based on carbon source utilization profiles also showed significant separation of soil microbial community under long-term fertilization regimes and NPKM treatment was significantly separated from the other three treatments primarily according to the higher microbial utilization of carbohydrates, carboxylic acids, polymers, phenolic compounds, and amino acid, while higher utilization of amines/amides differed soil microbial community in NPKS treatment from those in the other three treatments. Redundancy analysis(RDA) indicated that soil organic carbon(SOC) availability, especially soil microbial biomass carbon(Cmic) and Cmic/SOC ratio are the key factors of soil environmental characteristics contributing to the increase of both soil microbial community structure and functional metabolic diversity in the long-term fertilization trial. Our results showed that long-term inorganic fertilizer and swine manure application could significantly improve soil bacterial community structure and soil microbial metabolic activity through the increases in SOC availability, which could provide insights into the sustainable management of China's soil resource. 展开更多
关键词 long-term fertilization regimes organic amendment soil microbial community structure microbial functional metabolic activity carbon substrate utilization
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Altered intrinsic functional connectivity of the primary visual cortex in youth patients with comitant exotropia: a resting state fMRI study 被引量:11
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作者 Pei-Wen Zhu Xin Huang +5 位作者 Lei Ye Nan Jiang Yu-Lin Zhong Qing Yuan Fu-Qing Zhou Yi Shao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第4期668-673,共6页
AIM: To evaluate the differences in the functional connectivity(FC) of the primary visual cortex(V1) between the youth comitant exotropia(CE) patients and health subjects using resting functional magnetic reson... AIM: To evaluate the differences in the functional connectivity(FC) of the primary visual cortex(V1) between the youth comitant exotropia(CE) patients and health subjects using resting functional magnetic resonance imaging(f MRI) data.METHODS: Totally, 32 CEs(25 males and 7 females) and 32 healthy control subjects(HCs)(25 males and 7 females) were enrolled in the study and underwent the MRI scanning. Two-sample t-test was used to examine differences in FC maps between the CE patients and HCs. RESULTS: The CE patients showed significantly less FC between the left brodmann area(BA17) and left lingual gyrus/cerebellum posterior lobe, right middle occipital gyrus, left precentral gyrus/postcentral gyrus and right inferior parietal lobule/postcentral gyrus. Meanwhile, CE patients showed significantly less FC between right BA17 and right middle occipital gyrus(BA19, 37).CONCLUSION: Our findings show that CE involves abnormal FC in primary visual cortex in many regions, which may underlie the pathologic mechanism of impaired fusion and stereoscopic vision in CEs. 展开更多
关键词 comitant exotropia functional connectivity primary visual cortex spontaneous activity
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Evidence of cortical reorganization of language networks after stroke with subacute Broca's aphasia:a blood oxygenation level dependent-functional magnetic resonance imaging study 被引量:8
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作者 Wei-hong Qiu Hui-xiang Wu +7 位作者 Qing-lu Yang Zhuang Kang Zhao-cong Chen Kui Li Guo-rong Qiu Chun-qing Xie Gui-fang Wan Shao-qiong Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第1期109-117,共9页
Aphasia is an acquired language disorder that is a common consequence of stroke.The pathogenesis of the disease is not fully understood,and as a result,current treatment options are not satisfactory.Here,we used blood... Aphasia is an acquired language disorder that is a common consequence of stroke.The pathogenesis of the disease is not fully understood,and as a result,current treatment options are not satisfactory.Here,we used blood oxygenation level-dependent functional magnetic resonance imaging to evaluate the activation of bilateral cortices in patients with Broca's aphasia 1 to 3 months after stroke.Our results showed that language expression was associated with multiple brain regions in which the right hemisphere participated in the generation of language.The activation areas in the left hemisphere of aphasia patients were significantly smaller compared with those in healthy adults.The activation frequency,volumes,and intensity in the regions related to language,such as the left inferior frontal gyrus(Broca's area),the left superior temporal gyrus,and the right inferior frontal gyrus(the mirror region of Broca's area),were lower in patients compared with healthy adults.In contrast,activation in the right superior temporal gyrus,the bilateral superior parietal lobule,and the left inferior temporal gyrus was stronger in patients compared with healthy controls.These results suggest that the right inferior frontal gyrus plays a role in the recovery of language function in the subacute stage of stroke-related aphasia by increasing the engagement of related brain areas. 展开更多
关键词 nerve regeneration functional magnetic resonance imaging cortical functional connectivity language regions neuroplasticity Perisylvian language regions brain activation right hemisphere picture-naming task neural regeneration
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Effect of Preparation Process of Functional Polymer Active Materials on Properties of Gadolinium Ion Selective Electrode
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作者 车吉泰 闫美兰 +1 位作者 林安 张万喜 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第3期226-227,共2页
Recently we have studied the rare earth ion-selective electrodes with active materials of the func-tional polymers and found that the process chosen for the functional polymers had an effect on the propertiesof gadoli... Recently we have studied the rare earth ion-selective electrodes with active materials of the func-tional polymers and found that the process chosen for the functional polymers had an effect on the propertiesof gadolinium ion selective electrode besides the effects of their structures.1.Effect of preparation process of the grafted polymers on the properties ofgadolinium ion selective electrodesThe electrode membranes which consist of functional polymers as active materials were prepared by re-action of gadolinium chloride with the radiation grafted clmer of acrlic acid and polystyrene of which 展开更多
关键词 functional polymer active materials Gadolinium ion selective electrode Grafted polymers
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EFFECT OF STRUCTURE OF FUNCTIONAL POLYMER ACTIVE MATERIALS ON PROPERTIES OF GADOLINIUM ION SELECTIVE ELECTRODE
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作者 车吉泰 闫美兰 张万喜 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第3期189-193,共5页
In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- ti... In this paper,the functional polymeric active materials were prepared by the grafting copolymerization and their structure and properties were studied.The results show that the structure and properties of these ac- tive materials have the relative large effects on the properties of gadolinium ion selective electrodes. 展开更多
关键词 HDPE EFFECT OF STRUCTURE OF functional POLYMER ACTIVE MATERIALS ON PROPERTIES OF GADOLINIUM ION SELECTIVE ELECTRODE
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Correlation of cognitive function with acetylcholinesterase activity and P300 event-related potential of patients with type 2 diabetes mellitus
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作者 Suguo Yu Yingxue Wang Jihua Sun Xuewen Han 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第2期177-180,共4页
BACKGROUND: At present, central cholinergic neuron system is regarded the most major structural basis of cognitive function. Changes in structure of cholinergic neuron system of brain and receptor expression after br... BACKGROUND: At present, central cholinergic neuron system is regarded the most major structural basis of cognitive function. Changes in structure of cholinergic neuron system of brain and receptor expression after brain injury can cause cognitive impairment. OBJECTIVE" To comparatively observe the intelligence quotient (IQ), latent period and wave amplitude of P300 event-related potential and the difference of activity of acetylcholinesterase (ACHE) in blood and cerebrospinal fluid between patients with type 2 diabetes mellitus and with non-diabetes mellitus, and analyze the correlation of IQ of cognitive impairment patients with diabetes mellitus with AChE activity, latent period and wave amplitude of P300 event-related potential in cerebrospinal fluid. DESIGN: Correlation analysis of contrast observation SETTING: Department of Endocrinology, Affiliated Hospital of Binzhou Medical College PARTICIPANTS: Totally 32 patients with type 2 diabetes mellitus who received the treatment in the Department of Endocrinology, Affiliated Hospital of Binzhou Medical College between April 2004 and April 2005 were recruited, serving as diabetes mellitus group. They, including 19 male and 13 female, aged 49 to 73 years, with disease course of 4 to 11 years, all met the diagnostic criteria of diabetes mellitus revised by World Health Organization in 1999. Another 30 patients with non-diabetes mellitus who homeochronously underwent lumbar anesthesia in the Department of Surgery and Department of Gynecology were recruited, serving as non-diabetes mellitus group. The 30 patients included 18 male and 12 female, and their age ranged from 46 to 71 years. Informed consents of detected items were obtained from the involved patients. METHODS: ① Evaluation,on IQ: The IQ of involved subjects was evaluated with Chinese Version of the Wechsler Adult Intelligence Scale revised by Gong Yao-xian (WAIS-RC). WAIS-RC included 6 verbal subscales and 5 performance subscales. The test scores of the 11 subscales integrated into the scores of the whole scale, and the scores on the WAIS-RC included verbal IQ (VlQ), performance IQ (PIQ) and full scale IQ (FIQ). FIQ ≤79 scores indicated low IQ and FIQ≤69 indicated intelligence impairment. ② Detection of P300 wave: P300 wave was detected with evoked potential instrument (MYTOPRO, Italian), and data of latent period and amplitude of P300 event-related potential were automatically shown by computer. ③ Detection of AChE activity in blood and cerebrospinal fluid: Activity of AChE of blood and cerebrospinal fluid was measured with biochemical methods by using CORNING-560 autoanalyzer.④Correlation analysis: Correlation of FIQ with AChE of cerebrospinal fluid and P300 wave of patients with type 2 diabetes mellitus was analyzed, t test was used in intergroup comparison and linear correlation analysis for relevant treatment. MAIN OUTCOME MEASURES: ① Comparison of IQ, latent period and wave amplitude of P300 wave as well as the activity of AChE between two groups. ② Analysis on the correlation of FIQ of patients with type 2 diabetes mellitus with AChE of cerebrospinal fluid and P300 wave. RESULTS: Thirty-two patients with diabetes mellitus and 30 non-diabetes mellitus participated in the result analysis. ①Comparison of IQ, latent period and wave amplitude of P300 wave as well as the activity of AChE between two groups: The scores of VIP, PIQ and FIQ of patients with type 2 diabetes mellitus were (97.4±10.4). (92.6±8.4) and (95.2±9.7) scores, respectively; and those of patients with non-diabetes mellitus were (104.7±9.6), (102.5±8.5)and(102.7±8.9) scores, respectively, and P 〈 0.05-0.01 was set in intergroup comparison. The latent period of P300 wave at points Fz , Cz and Pz of patients with type 2 diabetes mellitus was (370.8±41.8).(371.5±39.1)and (375.1±43.1) ms, respectively, and that of patients with non-diabetes mellitus was ( 332.1 ±28.3 ), (335.7 ±29.4)and (339.7 ±27.3) ms, respectively, and P 〈 0.01 was set in intergroup comparison; Wave amplitude of P300 of patients with type 2 diabetes mellitus was (8.6±4.1),(8.6±4.0) and (7.7±4.0) μV, respectively and that of patients with non-diabetes mellitus was (11.9±4.1),(11.5±4.4) and (10.9±5.0) μV, respectively , and P 〈 0.05-0.01 was set in intergroup comparison; The level of AChE in blood and cerebrospinal fluid of patients with type 2 diabetes mellitus was (235.61 ±50.34)and (17.89±4.46) μkat/L, respectively, which was significantly higher than that of patients with non-diabetes mellitus [(205.03±44.15)and (14.63±0.48) μkat /L, respectively], and P 〈 0.05-0.01 was set in the intergroup comparison. ② Correlation of FIQ value of patients with type 2 diabetes mellitus with AChE of cerebrospinal fluid and P300 wave: The value of FIQ was significantly negatively correlated with the AChE activity of cerebrospinal fluid (r=-0.588 1, P 〈 0.01 ), significantly negatively correlated with the latent period at points Fz. C and Pz of P300 wave (r= -0.700 5, -0.689 4, -0.688 5, P 〈 0.01 ), and significantly positively correlated with the amplitude at points Fz . Cz and Pz of P300 wave(r= 0.607 4,0.616 1,0.592 0,P 〈 0.01 ). CONCLUSION: ① Cognitive impairment of patients with type 2 diabetes mellitus might be related to the increase of activity of AChE in cerebrospinal fluid. ②Combined application of examination of P300 wave and evaluation of IQ is more useful in deciding the state of cognitive function of patients with type 2 diabetes mellitus. 展开更多
关键词 TYPE Correlation of cognitive function with acetylcholinesterase activity and P300 event-related potential of patients with type 2 diabetes mellitus IQ
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Functional magnetic resonance imaging evidence for activated functional brain areas following acupoint needling in the extremities
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《Neural Regeneration Research》 SCIE CAS CSCD 2012年第3期223-223,共1页
Totally three articles focusing on functional magnetic resonance imaging features of brain function in the activated brain regions of stroke patients undergoing acupuncture on the healthy limbs and healthy controls un... Totally three articles focusing on functional magnetic resonance imaging features of brain function in the activated brain regions of stroke patients undergoing acupuncture on the healthy limbs and healthy controls undergoing acupuncture on the lower extremities are published in three issues. We hope that our readers find these papers useful to their research. 展开更多
关键词 functional magnetic resonance imaging evidence for activated functional brain areas following acupoint needling in the extremities
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Antitumor Activity and Theoretical Calculation of Evodiamine and Rutaecarpine
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作者 郭惠 张拴 +5 位作者 张珂瑶 朱海燕 刘靖丽 刘东梅 王昌利 苏卓 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第8期1174-1180,共7页
The antitumor activities of two alkaloids, evodiamine(EVO) and rutaecarpine(RUT), against MCF-7, SMMC-7721 and SW-1353 cells growth in vitro were investigated by MTT assay. The results showed that the anti-tumor e... The antitumor activities of two alkaloids, evodiamine(EVO) and rutaecarpine(RUT), against MCF-7, SMMC-7721 and SW-1353 cells growth in vitro were investigated by MTT assay. The results showed that the anti-tumor effects of two alkaloids were remarkably different. In order to discover the relationship of antitumor activity and structures of the compounds, the dihedral angle, Natural Electron Configuration, frontier molecular orbital profiles(HOMO, LUMO)and bandgaps of these two compounds have been studied based on density functional theory(DFT)by means of DFT-B3LYP/6-31G(d) in Gaussian 03. The calculation results of dihedral angle showed that EVO, due to the existence of methyl group attached to the N(14) atom, have non-planar and twisted structures, which decrease the stability of EVO and increase the activity of EVO. Furthermore, the bandgaps of RUT are lower than that of EVO, indicating RUT has higher stability than EVO, so the activity of EVO is higher than that of RUT. In addition, the negative charge of N14 atom in EVO is lower than that of in RUT, so the positive charge of N(14) atom in EVO is higher than that of in RUT, which suggests that the nucleophile is easier to aggress the N(14) atom in EVO than that in RUT, so the reason of the different antitumor activities of EVO and RUT may be attacked by nucleophile. 展开更多
关键词 evodiamine and rutaecarpine anticancer activity density functional theory MTT
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Theoretical Study on the C-H Activation in Decarbonylation of Acetaldehyde by NiL_2(L=SO_3CH_3) Using Density Functional Theory
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作者 刘红飞 JIA Tiekun MIN Xinmin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1170-1172,共3页
Density functional theory calculations were carried out to explore the potential energy surface(PES) associated with the gas-phase reaction of Ni L2(L=SO3CH3) with acetone. The geometries and energies of the react... Density functional theory calculations were carried out to explore the potential energy surface(PES) associated with the gas-phase reaction of Ni L2(L=SO3CH3) with acetone. The geometries and energies of the reactants, intermediates, products and transition states of the triplet ground potential energy surfaces of [Ni, O, C2, H4] were obtained at the B3LYP/6-311++G(d,p) levels in C,H,O atoms and B3LYP/ Lanl2 dz in Ni atom. It was found through our calculations that the decabonylation of acetaldehyde contains four steps including encounter complexation, C-C activation, aldehyde H-shift and nonreactive dissociation. The results revealed that C-C activation induced by Ni L2(L=SO3CH3) led to the decarbonylation of acetaldehyde. 展开更多
关键词 density functional theory decarbonylation transition state energy C-C activation
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Research Progress in the Extraction and Application of Flavonoids from Ginkgo biloba Leaves
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作者 Lili SONG Kaili LI 《Meteorological and Environmental Research》 CAS 2023年第2期50-52,56,共4页
Ginkgo biloba resources in China are enormous. With the demand of the market, the preparation and application of flavonoids have become a current research hotspot. The main active substances in G. biloba leaves, flavo... Ginkgo biloba resources in China are enormous. With the demand of the market, the preparation and application of flavonoids have become a current research hotspot. The main active substances in G. biloba leaves, flavonoids, have various functional activities and are widely used in fields such as food, medicine, cosmetics, feed, etc. In this paper, the introduction, functional activity, extraction methods, and application research of flavonoids from G. biloba leaves are reviewed, and the development prospects of flavonoids from G. biloba leaves are expected. 展开更多
关键词 Flavonoids from G.biloba leaves functional activity Extraction method Application and prospects
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Study on Marine actinomycetes and analysis of their secondary metabolites
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作者 Bao-Liang Xu Yuan-Yuan Wang Chun-Ming Dong 《Life Research》 2023年第4期1-15,共15页
Actinomycetes are relatively prevalent bacteria in the ocean,constituting 9% of the total number of marine bacteria.The advancement of science and technology has led to a more profound exploration of marine actinomyce... Actinomycetes are relatively prevalent bacteria in the ocean,constituting 9% of the total number of marine bacteria.The advancement of science and technology has led to a more profound exploration of marine actinomycetes.These studies hold immense significance in comprehending the distribution and adaptation of marine actinomycetes within the oceanic environment,as well as uncovering new secondary metabolites.Based on differing lifestyles,marine actinomycetes can be categorized as free-living or co-epiphytic.The activity and metabolism of actinomycetes vary across diverse marine settings,including the deep sea,benthic regions,and marine organisms.Due to their distinctive biological traits and genetic background,these marine actinomycetes inevitably generate metabolites possessing unique structures.Research methodologies concerning marine actinomycetes predominantly encompass traditional pure culture techniques,molecular biology approaches,and the integration of metagenomics and bioinformatics.The exploration of varied methodologies proves pivotal for the analysis of metabolite processes.Through the cultivation of marine actinomycetes,numerous compounds featuring novel structures and significant activities have been isolated,furnishing a substantial foundation for new drug investigations.These encompass,but are not restricted to,peptides,antibiotics,terpenoids,ketones,quinones,macrolides,and pigments.The potential applications of marine actinomyces and their secondary metabolites extend beyond antibacterial and anti-tumor effects,exhibiting promising prospects in antifungal and antiviral domains.This paper provides a comprehensive review of the classification,resources,research methodologies,and habitats of marine actinomycetes.Furthermore,it delves into the classification of secondary metabolites and their functional activities,facilitating a more exhaustive analysis of the secondary metabolites produced by marine actinomycetes. 展开更多
关键词 Marine actinomyces secondary metabolites research method functional activity
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A Universal Activation Function for Deep Learning
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作者 Seung-Yeon Hwang Jeong-Joon Kim 《Computers, Materials & Continua》 SCIE EI 2023年第5期3553-3569,共17页
Recently,deep learning has achieved remarkable results in fields that require human cognitive ability,learning ability,and reasoning ability.Activation functions are very important because they provide the ability of ... Recently,deep learning has achieved remarkable results in fields that require human cognitive ability,learning ability,and reasoning ability.Activation functions are very important because they provide the ability of artificial neural networks to learn complex patterns through nonlinearity.Various activation functions are being studied to solve problems such as vanishing gradients and dying nodes that may occur in the deep learning process.However,it takes a lot of time and effort for researchers to use the existing activation function in their research.Therefore,in this paper,we propose a universal activation function(UA)so that researchers can easily create and apply various activation functions and improve the performance of neural networks.UA can generate new types of activation functions as well as functions like traditional activation functions by properly adjusting three hyperparameters.The famous Convolutional Neural Network(CNN)and benchmark datasetwere used to evaluate the experimental performance of the UA proposed in this study.We compared the performance of the artificial neural network to which the traditional activation function is applied and the artificial neural network to which theUA is applied.In addition,we evaluated the performance of the new activation function generated by adjusting the hyperparameters of theUA.The experimental performance evaluation results showed that the classification performance of CNNs improved by up to 5%through the UA,although most of them showed similar performance to the traditional activation function. 展开更多
关键词 Deep learning activation function convolutional neural network benchmark datasets universal activation function
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Impact point prediction guidance of ballistic missile in high maneuver penetration condition
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作者 Yong Xian Le-liang Ren +3 位作者 Ya-jie Xu Shao-peng Li Wei Wu Da-qiao Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第8期213-230,共18页
An impact point prediction(IPP) guidance based on supervised learning is proposed to address the problem of precise guidance for the ballistic missile in high maneuver penetration condition.An accurate ballistic traje... An impact point prediction(IPP) guidance based on supervised learning is proposed to address the problem of precise guidance for the ballistic missile in high maneuver penetration condition.An accurate ballistic trajectory model is applied to generate training samples,and ablation experiments are conducted to determine the mapping relationship between the flight state and the impact point.At the same time,the impact point coordinates are decoupled to improve the prediction accuracy,and the sigmoid activation function is improved to ameliorate the prediction efficiency.Therefore,an IPP neural network model,which solves the contradiction between the accuracy and the speed of the IPP,is established.In view of the performance deviation of the divert control system,the mapping relationship between the guidance parameters and the impact deviation is analysed based on the variational principle.In addition,a fast iterative model of guidance parameters is designed for reference to the Newton iteration method,which solves the nonlinear strong coupling problem of the guidance parameter solution.Monte Carlo simulation results show that the prediction accuracy of the impact point is high,with a 3 σ prediction error of 4.5 m,and the guidance method is robust,with a 3 σ error of 7.5 m.On the STM32F407 singlechip microcomputer,a single IPP takes about 2.374 ms,and a single guidance solution takes about9.936 ms,which has a good real-time performance and a certain engineering application value. 展开更多
关键词 Ballistic missile High maneuver penetration Impact point prediction Supervised learning Online guidance Activation function
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Convolution-Based Heterogeneous Activation Facility for Effective Machine Learning of ECG Signals
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作者 Premanand.S Sathiya Narayanan 《Computers, Materials & Continua》 SCIE EI 2023年第10期25-45,共21页
Machine Learning(ML)and Deep Learning(DL)technologies are revolutionizing the medical domain,especially with Electrocardiogram(ECG),by providing new tools and techniques for diagnosing,treating,and preventing diseases... Machine Learning(ML)and Deep Learning(DL)technologies are revolutionizing the medical domain,especially with Electrocardiogram(ECG),by providing new tools and techniques for diagnosing,treating,and preventing diseases.However,DL architectures are computationally more demanding.In recent years,researchers have focused on combining the computationally less intensive portion of the DL architectures with ML approaches,say for example,combining the convolutional layer blocks of Convolution Neural Networks(CNNs)into ML algorithms such as Extreme Gradient Boosting(XGBoost)and K-Nearest Neighbor(KNN)resulting in CNN-XGBoost and CNN-KNN,respectively.However,these approaches are homogenous in the sense that they use a fixed Activation Function(AFs)in the sequence of convolution and pooling layers,thereby limiting the ability to capture unique features.Since various AFs are readily available and each could capture unique features,we propose a Convolutionbased Heterogeneous Activation Facility(CHAF)which uses multiple AFs in the convolution layer blocks,one for each block,with a motivation of extracting features in a better manner to improve the accuracy.The proposed CHAF approach is validated on PTB and shown to outperform the homogeneous approaches such as CNN-KNN and CNN-XGBoost.For PTB dataset,proposed CHAF-KNN has an accuracy of 99.55%and an F1 score of 99.68%in just 0.008 s,outperforming the state-of-the-art CNN-XGBoost which has an accuracy of 99.38%and an F1 score of 99.32%in 1.23 s.To validate the generality of the proposed CHAF,experiments were repeated on MIT-BIH dataset,and the proposed CHAF-KNN is shown to outperform CNN-KNN and CNN-XGBoost. 展开更多
关键词 ELECTROCARDIOGRAM convolution neural network machine learning activation function
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