Rock mass quality prediction on tunnel faces with incomplete multi-source dataset via tree-augmented naive Bayesian network

Rock mass quality serves as a vital index for predicting the stability and safety status of rock tunnel faces.In tunneling practice,the rock mass quality is often assessed via a combination of qualitative and quantitative parameters.However,due to the harsh on-site construction conditions,it is rather difficult to obtain some of the evaluation parameters which are essential for the rock mass quality prediction.In this study,a novel improved Swin Transformer is proposed to detect,segment,and quantify rock mass characteristic parameters such as water leakage,fractures,weak interlayers.The site experiment results demonstrate that the improved Swin Transformer achieves optimal segmentation results and achieving accuracies of 92%,81%,and 86%for water leakage,fractures,and weak interlayers,respectively.A multisource rock tunnel face characteristic(RTFC)dataset includes 11 parameters for predicting rock mass quality is established.Considering the limitations in predictive performance of incomplete evaluation parameters exist in this dataset,a novel tree-augmented naive Bayesian network(BN)is proposed to address the challenge of the incomplete dataset and achieved a prediction accuracy of 88%.In comparison with other commonly used Machine Learning models the proposed BN-based approach proved an improved performance on predicting the rock mass quality with the incomplete dataset.By utilizing the established BN,a further sensitivity analysis is conducted to quantitatively evaluate the importance of the various parameters,results indicate that the rock strength and fractures parameter exert the most significant influence on rock mass quality.

Application of different fiber structures and arrangements by electrospinning in triboelectric nanogenerators

In recent years,nanogenerators(NGs)have attracted wide attention in the energy field,among which triboelectric nanogenerators(TENGs)have shown superior performance.Multiple reports of electrospinning(ES)-based TENGs have been reported,but there is a lack of deep analysis of the designing method from microstructure,limiting the creative of new ES-based TENGs.Most TENGs use polymer materials to achieve corresponding design,which requires structural design of polymer materials.The existing polymer molding design methods include macroscopic molding methods,such as injection,compression,extrusion,calendering,etc.,combined with liquid-solid changes such as soluting and melting;it also includes micro-nano molding technology,such as melt-blown method,coagulation bath method,ES method,and nanoimprint method.In fact,ES technology has good controllability of thickness dimension and rich means of nanoscale structure regulation.At present,these characteristics have not been reviewed.Therefore,in this paper,we combine recent reports with some microstructure regulation functions of ES to establish a more general TENGs design method.Based on the rich microstructure research results in the field of ES,much more new types of TENGs can be designed in the future.

Centrifuge modeling of a large-scale surcharge on adjacent foundation

This study investigates the ground and structural response of adjacent raft foundations induced by largescale surcharge by ore in soft soil areas through a 130g centrifuge modeling test with an innovative layered loading device.The prototype of the test is a coastal iron ore yard with a natural foundation of deep soft soil.Therefore,it is necessary to adopt some measures to reduce the influence of the large-scale surcharge on the adjacent raft foundation,such as installing stone columns for foundation treatment.Under an acceleration of 130 g,the model conducts similar simulations of iron ore,stone columns,and raft foundation structures.The tested soil mass has dimensions of 900 mm×700 mm×300 mm(lengthwidthdepth),which is remodeled from the soil extracted from the drilling holes.The test conditions are consistent with the actual engineering conditions and the effects of four-level loading conditions on the composite foundation of stone columns,unreinforced zone,and raft foundations are studied.An automatic layer-by-layer loading device was innovatively developed to simulate the loading process of actual engineering more realistically.The composite foundation of stone columns had a large settlement after the loading,forming an obvious settlement trough and causing the surface of the unreinforced zone to rise.The 12 m surcharge loading causes a horizontal displacement of 13.19 cm and a vertical settlement of 1.37 m in the raft foundation.The stone columns located on both sides of the unreinforced zone suffered significant shear damage at the sand-mud interface.Due to the reinforcement effect of stone columns,the sand layer below the top of the stone columns moves less.Meanwhile,the horizontal earth pressure in the raft foundation zone increases slowly.The stone columns will form new drainage channels and accelerate the dissipation of excess pore pressure.

Haplotype-resolved and chromosome-scale genomes provide insights into co-adaptation between the Amur tiger and Amur leopard

DEAR EDITOR,Big cats,such as Amur tigers(Panthera tigris altaica)and Amur leopards(P.pardus orientalis),are apex predator and have evolved specialized traits for hunting and carnivory(Moya et al.,2022),thus playing a crucial role in maintaining biodiversity and ecosystem integrity by regulating prey-predator dynamics.However,human-induced pressures,habitat fragmentation,and environmental alterations have restricted these species in small and isolated populations.Currently,all extant big cats are categorized as endangered or threatened according to their conservation status.Amur tigers and Amur leopards share overlapping geographic ranges,habitats,and certain prey species in the forests of Northeast Asia(Jiang et al.,2015).To reduce interspecies conflict,these carnivores exhibit differentiated dietary and temporal niches.Amur tigers predominantly prey on large ungulates,while Amur leopards hunt small to medium-sized animals(Sugimoto et al.,2016).Additionally,they occupy different temporal niches,with tigers being active at night and leopards more active during the day.Despite spatial and temporal niche partitioning,interspecific competition between these two species is inevitable.Tigers,benefiting from their greater size,have a competitive advantage over leopards,which can manifest in occasional leopard predation by tigers and declines in leopard populations with increasing tiger density(Jiang et al.,2015).Tigers also displace leopards from marginal habitats in nature reserves where they coexist.

Map Reconstruction of Radio Observations with Conditional Invertible Neural Networks

In radio astronomy,the challenge of reconstructing a sky map from time ordered data is known as an inverse problem.Standard map-making techniques and gridding algorithms are commonly employed to address this problem,each offering its own benefits such as producing minimum-variance maps.However,these approaches also carry limitations such as computational inefficiency and numerical instability in map-making and the inability to remove beam effects in grid-based methods.To overcome these challenges,this study proposes a novel solution through the use of the conditional invertible neural network(cINN)for efficient sky map reconstruction.With the aid of forward modeling,where the simulated time-ordered data(TODs)are generated from a given sky model with a specific observation,the trained neural network can produce accurate reconstructed sky maps.Using the Five-hundred-meter Aperture Spherical radio Telescope as an example,cINN demonstrates remarkable performance in map reconstruction from simulated TODs,achieving a mean squared error of2.29±2.14×10^(-4)K^(2),a structural similarity index of 0.968±0.002,and a peak signal-to-noise ratio of26.13±5.22 at the 1σlevel.Furthermore,by sampling in the latent space of cINN,the reconstruction errors for each pixel can be accurately quantified.

免疫检查点抑制剂相关抗神经元抗体阳性副肿瘤神经综合征临床特征分析

目的 分析抗神经元抗体阳性免疫检查点抑制剂相关副肿瘤神经综合征(ICI-PNS)的临床特征。方法与结果 纳入2012年1月至2024年3月中国医学科学院北京协和医院诊断与治疗的5例抗神经元抗体阳性ICI-PNS患者,肿瘤类型包括小细胞肺癌(2例)、恶性黑色素瘤(1例)、霍奇金淋巴瘤(1例)、宫颈癌(1例),免疫检查点抑制剂包括程序性死亡蛋白-1抑制剂(3例)、程序性死亡蛋白配体-1抑制剂(1例)、程序性死亡蛋白-1/细胞毒性T细胞相关抗原4双抑制剂(1例)。5例患者均出现副肿瘤神经综合征的高风险表型,其中4例表现为边缘性脑炎,1例表现为快速进展的小脑综合征。血清和(或)脑脊液中检出的抗神经元抗体包括抗Hu、γ-氨基丁酸B型受体、Y染色体性别决定区相关高迁移率组盒蛋白1、代谢型谷氨酸受体5型、Yo抗体。4例神经系统症状出现在应用免疫检查点抑制剂2周内。4例病情达峰时改良Rankin量表评分为3分,1例为5分。5例患者常见不良事件评价标准分级(CTCAE)均为3级。治疗方面,停用免疫检查点抑制剂,给予糖皮质激素联合静脉注射免疫球蛋白治疗,神经系统症状均有改善。结论 中高风险抗神经元抗体是ICI-PNS的诊断标志物,可依据ICI-PNS临床表型及CTCAE分级等综合制定免疫治疗方案,停用免疫检查点抑制剂,应用糖皮质激素、静脉注射免疫球蛋白可以改善患者预后。

球孢白僵菌对中蜂外勤蜂慢性毒性测定

球孢白僵菌广泛应用于农林害虫防治,中蜂外出采集活动时可能会接触到球孢白僵菌。为了探明球孢白僵菌对中蜂外勤蜂的影响。配制含不同浓度(10~5、10~6、10~7孢子/mL)的球孢白僵菌分生孢子,在室内30℃、60%RH条件下测试对中蜂外勤蜂的慢性毒性。结果表明,中蜂外勤蜂接触球孢白僵菌(10~5、10~6、10~7孢子/mL)14天后,三组的校正死亡率分别为36.4%、68.2%、100%,生存率显著低于对照组,呈剂量毒性效应关系,说明球孢白僵菌对中蜂外勤工蜂的触杀毒性强。而取食10~5、10~6、10~7孢子/mL孢子糖液的工蜂生存曲线与剂量无对应关系,说明外勤蜂食入白僵菌孢子后无明显毒性。建议在球孢白僵菌施用期间,宜避开中蜂养殖区或开花的蜜粉源,或蜂群转场,以减少对中蜂的触杀毒害。

Inelastic Scattering of Dark Matter with Heavy Cosmic Rays

We investigate the impact of inelastic collisions between dark matter(DM)and heavy cosmic ray(CR)nuclei on CR propagation.We approximate the fragmentation cross-sections for DM-CR collisions using collider-measured proton-nuclei scattering cross-sections,allowing us to assess how these collisions affect the spectra of CR boron and carbon.We derive new CR spectra from DM-CR collisions by incorporating their cross-sections into the source terms and solving the diffusion equation for the complete network of reactions involved in generating secondary species.In a specific example with a coupling strength of b_(χ)=0.1 and a DM mass of m_(χ)=0.1 GeV,considering a simplified scenario where DM interacts exclusively with oxygen,a notable modification in the boron-to-carbon spectrum due to the DM-CR interaction is observed.Particularly,the peak within the spectrum,spanning from 0.1 to 10 GeV,experiences an enhancement of approximately 1.5 times.However,in a more realistic scenario where DM particles interact with all CRs,this peak can be amplified to twice its original value.Utilizing the latest data from AMS-02 and DAMPE on the boron-to-carbon ratio,we estimate a 95%upper limit for the effective inelastic cross-section of DM-proton as a function of DM mass.Our findings reveal that at m_(χ)?2 MeV,the effective inelastic cross-section between DM and protons must be less than O(10^(-32))cm^(2).

Gut microbiota modulating intestinal stem cell differentiation

Proliferation and differentiation of intestinal stem cell(ISC)to replace damaged gut mucosal epithelial cells in inflammatory states is a critical step in ameliorating gut inflammation.However,when this disordered proliferation continues,it induces the ISC to enter a cancerous state.The gut microbiota on the free surface of the gut mucosal barrier is able to interact with ISC on a sustained basis.Micro-biota metabolites are able to regulate the proliferation of gut stem and progenitor cells through transcription factors,while in steady state,differentiated colono-cytes are able to break down such metabolites,thereby protecting stem cells at the gut crypt.In the future,the gut flora and its metabolites mediating the regulation of ISC differentiation will be a potential treatment for enteropathies.

A Review on Swarm Intelligence and Evolutionary Algorithms for Solving Flexible Job Shop Scheduling Problems

Flexible job shop scheduling problems(FJSP)have received much attention from academia and industry for many years.Due to their exponential complexity,swarm intelligence(SI)and evolutionary algorithms(EA)are developed,employed and improved for solving them.More than 60%of the publications are related to SI and EA.This paper intents to give a comprehensive literature review of SI and EA for solving FJSP.First,the mathematical model of FJSP is presented and the constraints in applications are summarized.Then,the encoding and decoding strategies for connecting the problem and algorithms are reviewed.The strategies for initializing algorithms?population and local search operators for improving convergence performance are summarized.Next,one classical hybrid genetic algorithm(GA)and one newest imperialist competitive algorithm(ICA)with variables neighborhood search(VNS)for solving FJSP are presented.Finally,we summarize,discus and analyze the status of SI and EA for solving FJSP and give insight into future research directions.

Leptin activates the JAK/STAT pathway to promote angiogenesis in RF/6A cells in vitro

AIM: To investigate the effect of leptin on the angiogenesis of RF/6 A cells(monkey retinal choroidal endothelial cells) in vitro and test the cellular signaling in the mechanism.METHODS: RF/6 A cells were cultured in vitro and randomly divided into four groups: normal control, with leptin at 50, 100, 200 ng/m L for cell counting kit-8(CCK8). RF/6 A cell proliferation and migration were examined by Transwell assays, while RF/6 A cell tube formation by Matrigel assay. JAK2, p-JAK2, STAT3, and p-STAT3 protein expression was measured by Western blotting. Cells were then divided into the following treatment groups: control, 100 ng/m L leptin and AG-490(100 ng/m L leptin+10 μmol/L AG-490) for examinations of RF/6 A cellular behaviour again. Analysis of differences was carried out using one-way ANOVA and least significant difference(LSD).RESULTS: RF/6 A cell proliferation, migration and cell tube formation were promoted significantly by leptin in a dose-dependent manner(P<0.05). Western blotting showed that leptin up-regulated p-JAK2 and p-STAT3 expression levels. Treatment with the JAK/STAT pathway inhibitor, AG-490, decreased leptin-induced p-JAK2 and p-STAT3 expression, and inhibited cell proliferation, migration and cell tube formation induced by leptin(P<0.05). CONCLUSION: Leptin can promote RF/6 A cell angiogenesis in vitro via activation of the JAK2/STAT3 signaling pathway.

Bioinformatic analysis of chromatin organization and biased expression of duplicated genes between two poplars with a common whole-genome duplication

The nonrandom three-dimensional organization of chromatin plays an important role in the regulation of gene expression.However,it remains unclear whether this organization is conserved and whether it is involved in regulating gene expression during speciation after whole-genome duplication(WGD)in plants.In this study,high-resolution interaction maps were generated using high-throughput chromatin conformation capture(Hi-C)techniques for two poplar species,Populus euphratica and Populus alba var.pyramidalis,which diverged~14 Mya after a common WGD.We examined the similarities and differences in the hierarchical chromatin organization between the two species,including A/B compartment regions and topologically associating domains(TADs),as well as in their DNA methylation and gene expression patterns.We found that chromatin status was strongly associated with epigenetic modifications and gene transcriptional activity,yet the conservation of hierarchical chromatin organization across the two species was low.The divergence of gene expression between WGD-derived paralogs was associated with the strength of chromatin interactions,and colocalized paralogs exhibited strong similarities in epigenetic modifications and expression levels.Thus,the spatial localization of duplicated genes is highly correlated with biased expression during the diploidization process.This study provides new insights into the evolution of chromatin organization and transcriptional regulation during the speciation process of poplars after WGD.

Machine learning-based real-time visible fatigue crack growth detection

Many large-scale and complex structural components are applied in the aeronautics and automobile industries.However,the repeated alternating or cyclic loads in service tend to cause unexpected fatigue fractures.Therefore,developing real-time and visible monitoring methods for fatigue crack initiation and propagation is critically important for structural safety.This paper proposes a machine learning-based fatigue crack growth detection method that combines computer vision and machine learning.In our model,computer vision is used for data creation,and the machine learning model is used for crack detection.Then computer vision is used for marking and analyzing the crack growth path and length.We apply seven models for the crack classification and find that the decision tree is the best model in this research.The experimental results prove the effectiveness of our method,and the crack length measurement accuracy achieved is 0.6 mm.Furthermore,the slight machine learning models help us realize real-time and visible fatigue crack detection.

Glycation of high-density lipoprotein triggers oxidative stress and promotes the proliferation and migration of vascular smooth muscle cells

Background In type 2 diabetes mellitus （T2DM）, high-density lipoprotein （HDL） impairs its anti-atherogenic properties and even develops to a pro-inflammatory and pro-atherogenic phenotype because of abnormal compositions and modifications. In this study, we ex- amined the effects and the related mechanisms of glycation of HDL on the proliferation and migration of vascular smooth muscle cells （VSMCs）. Methods ＆ Results Glycated HDL （G-HDL） was modified with D-glucose （25 mmol/L） in vitro. Diabetic HDL （D-HDL） was isolated from T2DM patients. Rat VSMCs were isolated from the thoracic aortas. Human VSMCs were obtained from ScienCell Research Laboratories. Alpha-actin was detected through immunofiuorescence. VSMC proliferation was assayed by Cell Count. VSMC migration was determined by transwell chamber and scratch-wound assay. Intracellular reactive oxygen species （ROS） was detected based on ROS-medi- ated 2＇,7＇-dichlorofluorescein （DCFH-DA） fluorescence. Compared to native HDL （N-HDL）, G-HDL remarkably promoted VSMC prolif- eration and migration in the dose and time-dependent manners. In addition, G-HDL enhanced ROS generation in VSMCs. However, the ROS scavenger, N-acetylcysteine, efficiently decreased ROS production and subsequently inhibited the proliferation of VSMCs induced by G-HDL. Similarly, D-HDL from T2DM patients also promoted ROS release and VSMC proliferation and migration. Conclusions HDL either glycated in vitro or isolated from T2DM patients triggered VSMC proliferation, migration, and oxidative stress. These results might partly interpret the higher morbidity of cardiovascular disease in T2DM patients.

Genetic diversity and population structure of Hibiscus aridicola, an endangered ornamental species in dry-hot valleys of Jinsha River

Hibiscus aridicola is an endangered ornamental shrub of the family Malvaceae that is endemic to the dryhot valleys of Jinsha River in southwestern China.This species is a typical plant species with extremely small populations(PSESP).To support and monitor future conservation,develop management measures,and genotype this species,we performed extensive field studies together with genetic analyses.Specifically,we screened eleven microsatellite loci of 69 individuals of H.aridicola from four accessions.The population genetics analyses indicated that H.aridicola possesses high genetic diversity at both the population(0.6962-0.7293)and species level(0.7837)compared to other endemic/endangered species in China.The low differentiation of populations(Fst=0.0971)and the high gene flow between populations of H.aridicola(Nm=2.3236)could be due to its distribution along rivers in the hot-valleys of the Jinsha River and the wind-mediated dispersal of its seeds.Furthermore,the genetic diversity of H.aridicola is slightly positively correlated with geographic distance.Two populations are undergoing a genetic bottleneck,and require more specific attention from conservationists.Additionally,our analyses of the population genetics of H.aridicola demonstrate that the declines in populations are not the result of the internal genetics of these populations but due to external human activities over the past decades.

Co-luminescence properties of terbium ions–benzoic acid–phen complexes doped with europium ions

Series of complexes Eux Tb1-x(BA)3phen(0.01 B x B 0.50)were synthesized by co-precipitation method,BA was used as the carboxylic acid ligand and 1,10-phenanthroline was used as the electrically neutral ligand.The samples were characterized by means of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),thermal gravimetric analyses and differential scanning calorimetry(TG–DSC),ultraviolet and visible spectrophotometer absorption spectra,and photoluminescence spectra to study the structure,the energy absorption,the thermal,and luminescent properties of the rare earth complexes.The results show that the series rare earth organic complexes are well crystallized and show high thermal stability.The luminescent intensity of europium ion in the complexes increases as terbium ion transfers the absorbed energy to europium ion in the complexes.The emission of terbium ion at 545 nm is not quenched by europium ion but increases with the content of europium ion decreasing.When the x value is 0.01,the fluorescence intensity reaches the maximum as well as the emission intensity of terbium ions at 545 nm and europium ions at614 nm are almost equal.It realizes the co-luminescence phenomenon of terbium ion and europium ion.The series rare earth organic complexes with different colors can be obtained by adjusting the ratio of terbium ion and europium ion.

Toripalimab combined with targeted therapy and chemotherapy achieves pathologic complete response in gastric carcinoma:A case report

BACKGROUND Neoadjuvant or perioperative chemotherapy combined with surgery can reduce postoperative recurrence and improve the long-term survival rate of patients with locally advanced resectable gastric carcinoma.Nivolumab combined with chemotherapy has been recommended by the National Comprehensive Cancer Network guidelines as a first-line therapy for advanced gastric carcinoma/adenocarcinoma of the gastroesophageal junction and serves as the basis for immunotherapy combined with chemotherapy to become a neoadjuvant therapy.Herein,we report a case in which pathologic complete response was achieved by neoadjuvant administration of toripalimab,Herceptin,and docetaxel,oxaliplatin,calcium folinate,and fluorouracil(FLOT)chemotherapy followed by surgery for human epidermal growth factor receptor 2(HER2)-and programmed deathligand 1(PD-L1)-positive locally advanced gastric carcinoma.We hope that this case will shed some light on neoadjuvant therapy for gastric carcinoma.CASE SUMMARY The patient was diagnosed with locally advanced adenocarcinoma of the cardia.Immunohistochemistry of the baseline tissues suggested that the tissues were HER2-(fluorescent in situ hybridization)and PD-L1-positive(combined positive score=1).The patient underwent surgery following a four-cycle neoadjuvant therapy comprising Herceptin,toripalimab,and FLOT chemotherapy.The postoperative pathological findings showed mild atypical hyperplasia of the local glands with chronic mucosal inflammation(proximal stomach),no clear residual tumor(tumor regression grade 0),no regional lymph node metastasis,and negative upper and lower cut ends.The levels of tumor markers were reduced to normal levels after re-examination.With good postoperative recovery,the four-cycle preoperative chemotherapy was continued at the same dosage as that previously administered.After the treatment,the patient was monitored every 3 mo with a follow-up of 12 mo(4 times).As of February 27,2022,he was in a good condition without disease progression.The clinical trial registration number is E2019401.CONCLUSION There are many ongoing studies on neoadjuvant immunotherapy combined with chemotherapy or radiotherapy;however,most of these studies are phase II studies with small cohorts.According to the results of some current studies,these combined regimens have shown promising results in terms of efficacy and safety.However,the clinical efficacy and safety of the neoadjuvant therapies used in these combined regimens need to be confirmed by additional prospective phase III clinical trials,and further exploration of molecular markers for effective populations is required.

Reconstruction of meandering paleo-channels using dense well data,Daqing Oil Field,Songliao Basin,China

Reconstructing meandering paleo-channels is attracting global research attention. We implemented a novel method by comprehensively integrating migration models and sedimentary structures. Firstly, the migration architectures of the corresponding characteristics in planform and cross-sectional models were summarised as expansion, translation, expansion and translation, expansion and downstream rotation, constriction and downstream rotation, and expansion and countercurrent rotation models. Secondly, full continuous core data from 270 dense drilling wells were collected from the Daqing Oil Field in the Songliao Basin, China, providing information on rock textures, sedimentary cycles, and boundary information for the two layers being studied. Through a comprehensive analysis of dense drill cores and logging data, the abandoned channels and the initial and final channel centrelines were identified. Consequently, four profiles, including one longitudinal and three transverse sections, were constructed to reveal the cross-sectional structures and planform migration architecture. Profile interpretation revealed the evolution from the initial channel centreline to the final centreline. Using a method of rational interpolation, we were able to reconstruct the migration architecture of the meandering channels. The results showed that the average ancient bankfull width(Wc) was approximately 100 m, a single meandering belt was800 m, the radius of the curvature was 250 m, the length of the channel bend was 700 m, the average meander wavelength was 1300 m, the sinuosity was 3.0, and the annual average discharge rate was 450 m3/s. Furthermore, we compared the results from empirical equations, which verified that our reconstruction is both feasible and potentially widely applicable.

Synthesis and characterization of Fe_3O_4@SiO_2 magnetic composite nanoparticles by a one-pot process

Fe3O4@SiO2 core–shell composite nanoparticles were successfully prepared by a one-pot process. Tetraethyl-orthosilicate was used as a surfactant to synthesize Fe3O4@SiO2 core–shell structures from prepared Fe3O4 nanoparticles. The properties of the Fe3O4 and Fe3O4@SiO2 composite nanoparticles were studied by X-ray diffraction, transmission electron microscopy, energy dispersive spectroscopy, and Fourier transform infrared spectroscopy. The prepared Fe3O4 particles were approximately 12 nm in size, and the thickness of the SiO2 coating was approximately 4 nm. The magnetic properties were studied by vibrating sample magnetometry. The results show that the maximum saturation magnetization of the Fe3O4@SiO2 powder（34.85 A·m^2·kg^–1） was markedly lower than that of the Fe3O4 powder（79.55 A·m^2·kg^–1）, which demonstrates that Fe3O4 was successfully wrapped by SiO2. The Fe3O4@SiO2 composite nanoparticles have broad prospects in biomedical applications; thus, our next study will apply them in magnetic resonance imaging.

Using granger-geweke causality model to evaluate the effective connectivity of primary motor cortex, supplementary motor area and cerebellum

Currently, Granger-Geweke causality models have been widely applied to investigate the dynamic direction relationships among brain regions. In a previous study, we have found that the right hand finger-tapping task can produce relatively reliable brain response. As an extension of our previous study, we developed an algorithm based on the classical Granger- Geweke causality model to further investigate the effective connectivity of three brain regions (left primary motor cortex (M1), supplementary motor area (SMA) and right cerebellum) that showed the most robust brain activations. Our computational results not only confirm the strong linear feedback among SMA, M1 and right cerebellum, but also demonstrate that M1 is the hub of these three regions indicated by the anatomy research. Moreover, the model predicts the high intermediate node density existing in the area between SMA and M1, which will stimulate the imaging experimentalists to carry out new experiments to validate this postulation.