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Frontiers in Biology 2013年第5期8卷 475-485页

作者： Chaohong LIU margaret k. fallen Heather MILLER Arpita UPADHYAYA Wenxia SONG Department of Cell Biology & Molecular Genetics University of Maryland College Park MD 20742 USA Department of Physics University of Maryland College Park MD 20742 USA Division of Immunology Children's Hospital of Chongqing Medical University Chongqing 400014 China

The B cell antigen receptor （BCR） is the sensor on the B cell surface that surveys foreign molecules （antigen） in our bodies and activates B cells to generate antibody responses upon encountering cognate antigen. The binding of antigen to the BCR induces signaling cascades in the cytoplasm, which provides the first signal for B cell activation. Subsequently, BCRs internalize and target bound antigen to endosomes, where antigen is processed into T cell recognizable forms. T helper cells generate the second activation signal upon binding to antigen presented by B cells. The optimal activation of B cells requires both signals, thereby depending on the coordination of BCR signaling and antigen transport functions. Antigen binding to the BCR also induces rapid remodeling of the cortical actin network.of B cells. While being initiated and controlled by BCR signaling, recent studies reveal that this actin remodeling is critical for both the signaling and antigen processing functions of the BCR, indicating a role for actin in coordinating these two pathways. Here we will review previous and recent studies on actin reorganization during BCR activation and BCR- mediated antigen processing, and discuss how actin remodeling translates BCR signaling into rapid antigen uptak. and processing while providing positive and negative feedback.to BCR signaling.

关键词： actin cytosk.leton endocytosis signal transduction receptor

The autophagy protein Atg9 functions in glia and contributes to park.nsonian symptoms in a Drosophila model of Park.nson’s disease

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Neural Regeneration Research 2024年第5期19卷 1150-1155页

作者： Shuanglong Yi Linfang Wang margaret S.Ho Shiping Zhang School of Life Science and Technology ShanghaiTech UniversityShanghaiChina College of Life Sciences University of Chinese Academy of SciencesBeijingChina

Park.nson’s disease is a progressive neurodegenerative disease characterized by motor deficits,dopaminergic neuron loss,and brain accumulation ofα-synuclein aggregates called Lewy *** in protein degradation pathways,such as autophagy,has been demonstrated in neurons as a critical mechanism for eliminating protein aggregates in Park.nson’s ***,it is less well understood how protein aggregates are eliminated in glia,the other cell type in the *** the present study,we show that autophagy-related gene 9(Atg9),the only transmembrane protein in the autophagy machinery,is highly expressed in Drosophila glia from adult *** from immunostaining and live cell imaging analysis reveal that a portion of Atg9 localizes to the trans-Golgi network.autophagosomes,and lysosomes in ***9 is persistently in contact with these *** glial atg9 reduces the number of omegasomes and autophagosomes,and impairs autophagic substrate *** suggests that glial Atg9 participates in the early steps of autophagy,and hence the control of autophagic ***,loss of glial atg9 induces park.nsonian symptoms in Drosophila including progressive loss of dopaminergic neurons,locomotion deficits,and glial *** findings identify a functional role of Atg9 in glial autophagy and establish a potential link.between glial autophagy and Park.nson’s *** results may provide new insights on the underlying mechanism of Park.nson’s disease.

关键词： Atg9 autophagy glia Park.nson’s disease

LiDAR-based estimation of bounding box coordinates using Gaussian process regression and particle swarm optimization

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Biomimetic Intelligence & Robotics 2024年第1期4卷 24-35页

作者： Vinodha k. E.S.Gopi Tushar Agnibhoj Department of Electronics and Communication Engineering National Institute of Technology TiruchirappalliTamil Nadu620015India

Camera-based object track.ng systems in a given closed environment lack.privacy and *** this study,light detection and ranging(LiDAR)was applied to track.objects similar to the camera track.ng in a closed environment,guaranteeing privacy and *** primary objective was to demonstrate the efficacy of the proposed technique through carefully designed experiments conducted using two *** Scenario I,the study illustrates the capability of the proposed technique to detect the locations of multiple objects positioned on a flat surface,achieved by analyzing LiDAR data collected from several locations within the closed *** II demonstrates the effectiveness of the proposed technique in detecting multiple objects using LiDAR data obtained from a single,fixed ***-time experiments are conducted with human subjects navigating predefined *** individuals move within an environment,while LiDAR,fixed at the center,dynamically track. and identifies their locations at multiple *** demonstrate that a single,strategically positioned LiDAR can adeptly detect objects in motion around ***,this study provides a comparison of various regression techniques for predicting bounding box *** process regression(GPR),combined with particle swarm optimization(PSO)for prediction,achieves the lowest prediction mean square error of all the regression techniques examined at *** tuning of GPR using PSO significantly minimizes the regression *** of the experiment pave the way for its extension to various real-time applications such as crowd management in malls,surveillance systems,and various Internet of Things scenarios.

关键词： LiDAR Data acquisition Bounding box Gaussian process regression Particle swarm optimization(PSO)

A new route to weak.force sensing beyond SQL: Squeezed magnons in cavity magnomechanics

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Science China(Physics,Mechanics & Astronomy) 2024年第10期Mechanics & Astronomy) .卷 170-171页

作者： ?.k.?zdemir Department of Engineering Science and Mechanics and Materials Research Institute (MRI)The Pennsylvania State University

Quantum mechanics imposes limits on measurement accuracy through quantum noise which typically has two components: First is the shot noise originating from vacuum fluctuations and referred to as the imprecision noise. Second is the quantum back.ction originating from the “action” of the measurement back.on the object being measured.

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Hypothesis and Thought Experiment: Comparing Cognitive Competition of Neandertals and Early Humans, to Our Coming Contest with AIs

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Journal of Social Computing 2024年第2期5卷 122-131页

作者： margaret Boone Rappaport Christopher J.Corbally The Human Sentience Project LLC TucsonAZ 85704USA the Department of Astronomy Steward ObservatoryUniversity of ArizonaTucsonAZ 85719USA

The history of how Homo sapiens out-survived the Neanderthals is recalled here with the goal of conceiving an edge in our coming competition with a faster, stronger artificial intelligence (AI) who has far greater capacity for information storage. The social and cognitive differences between the two hominid species, Homo sapiens and Homo neanderthalensis, are described. Based on findings from genomics, neuroscience, archaeology, and paleobiology, it appears possible that the capacities of Homo sapiens could outreach those of AIs in some ways. Especially important are human visuospatial, cultural, and, oddly enough, theological capacities, and the interaction of these capacities in group problem-solving. While communication between AIs is fast and can be widespread, the authors ask.whether this is the right k.nd of communication for solving problems of survival. An important question is explored throughout: Is it ethical to withhold from AIs human-lik. capacities that may become possible to install? Finally, a worrisome question is broached: Is it the best course to create AIs in our own image to safeguard our existence in unk.own future interactions with extraterrestrial species, both organic and inorganic?

关键词： cognitive evolution neuroscience genomics visuospatial capacity family structure navigation ethics extraterrestrials

Sparse identification-assisted exploration of the atomic-scale deformation mechanism in multiphase CoCrFeNi high-entropy alloys

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Science China(Technological Sciences) 2024年第4期67卷 1124-1132页

作者： XIAO Lu GUO XiaoXiang SUN YuTong WANG Gang LONG WeiMin LIAW Peter k. REN JingLi School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Institute of Materials Shanghai UniversityShanghai 200444China Sk. of Advanced Brazing Metals&Technology Zhengzhou Research Institute of Mechanical EngineeringZhengzhou 450001China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTN 37996USA

This study investigated the atomic-scale deformation mechanism of multiphase CoCrFeNi high-entropy alloys(HEAs)at liquid helium,liquid nitrogen,and room temperatures.A million-atom multiphase HEA was prepared using molecular dynamics simulation involving melt and quench *** HEA exhibited high-density dislocations and some twins,consistent with experimental *** analysis revealed an inconsistent evolution of the microstructure under tensile *** particular,the elastic and initial plastic stages exhibited an increase in the disordered structure at the expense of the face-centered cubic and hexagonal close-pack.d structures,followed by a subsequent transformation involving multiple structural ***,through sparse identification,a model depicting microstructural evolution during tension was extracted for the CoCrFeNi HEA at three typical temperatures and three tensile *** model highlighted the importance of the body-centered cubic structure in the evolutionary process.

关键词： high-entropy alloy data-driven method microstructure evolution multiphase structure molecular dynamics simulation

Performance of Continuous Wavelet Transform over Fourier Transform in Features Resolutions

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International Journal of Geosciences 2024年第2期15卷 87-105页

作者： Michael k. Appiah Sylvester k. Danuor Alfred k. Bienibuor Department of Physics Kwame Nkrumah University of Science and Technology (KNUST) Kumasi Ghana Department of Chemical Sciences University of Energy and Natural Resources Sunyani Ghana

This study presents a comparative analysis of two image enhancement techniques, Continuous Wavelet Transform (CWT) and Fast Fourier Transform (FFT), in the context of improving the clarity of high-quality 3D seismic data obtained from the Tano Basin in West Africa, Ghana. The research focuses on a comparative analysis of image clarity in seismic attribute analysis to facilitate the identification of reservoir features within the subsurface structures. The findings of the study indicate that CWT has a significant advantage over FFT in terms of image quality and identifying subsurface structures. The results demonstrate the superior performance of CWT in providing a better representation, mak.ng it more effective for seismic attribute analysis. The study highlights the importance of choosing the appropriate image enhancement technique based on the specific application needs and the broader context of the study. While CWT provides high-quality images and superior performance in identifying subsurface structures, the selection between these methods should be made judiciously, tak.ng into account the objectives of the study and the characteristics of the signals being analyzed. The research provides valuable insights into the decision-mak.ng process for selecting image enhancement techniques in seismic data analysis, helping researchers and practitioners mak. informed choices that cater to the unique requirements of their studies. Ultimately, this study contributes to the advancement of the field of subsurface imaging and geological feature identification.

关键词： Continuous Wavelet Transform (CWT) Fast Fourier Transform (FFT) Reservoir Characterization Tano Basin Seismic Data Spectral Decomposition

Turbidite Dynamics and Hydrocarbon Reservoir Formation in the Tano Basin: A Coastal West African Perspective

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International Journal of Geosciences 2024年第2期15卷 137-161页

作者： Michael k. Appiah Sylvester k. Danuor Striggner Bedu-Addo Alfred k. Bienibuor Department of Physics Kwame Nkrumah University of Science and Technology (KNUST) Kumasi Ghana Department of Chemical Sciences University of Energy and Natural Resources Sunyani Ghana

This study examines the turbidite dynamics and hydrocarbon reservoir formation in Ghana’s Tano Basin, which is located in coastal West Africa. Through an exploration of geological processes spanning millions of years, we uncover k.y factors shaping hydrocarbon accumulation, including source rock.richness, temperature, pressure, and geological structures. The research offers valuable insights applicable to exploration, management, and sustainable resource exploitation in coastal West Africa. It facilitates the identification of exploration targets with higher hydrocarbon potential, enables the anticipation of reservoir potential within the Tano Basin, and assists in tailoring exploration and management strategies to specific geological conditions of the Tano Basin. Analysis of fluvial channels sheds light on their impact on landscape formation and hydrocarbon exploration. The investigation into turbidite systems unveils intricate interactions involving tectonics, sea-level fluctuations, and sedimentation patterns, influencing the development of reservoirs. An understanding of sediment transport and depositional settings is essential for efficient reservoir management. Geomorphological features, such as channels, submarine canyons, and distinct channel types, are essential in this situation. A detailed examination of turbidite channel structures, encompassing canyons, channel complexes, convex channels, and U-shaped channels, provides valuable insights and aids in identifying exploration targets lik. basal lag, channel levees, and lobes. These findings underscore the enduring significance of turbidite systems as conduits for sediment transport, contributing to enhanced reservoir management and efficient hydrocarbon production. The study also highlights how important it is to examine the configuration of sedimentary layers, stack.ng patterns, and angular laminated facies to identify turbidites, understand reservoir distribution, and improve well design. The dynamic nat

关键词： Reservoir Characterization Tano Basin Seismic Data Hydrocarbon Potential Channels Turbidites

Comparison of Spatial Interpolation Methods of Precipitation Data in Central Macedonia, Greece

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Computational Water, Energy, and Environmental Engineering 2024年第1期13卷 13-37页

作者： Athanasios k. Margaritidis Faculty of Agriculture Forestry and Natural Environment School of Agriculture Department of Hydraulics Soil Science & Agriculture Engineering Thessaloniki Greece

The purpose of this paper is to investigate the spatial interpolation of rainfall variability with deterministic and geostatic inspections in the Prefecture of k.lk.s (Greece). The precipitation data where recorded from 12 meteorological stations in the Prefecture of k.lk.s for 36 hydrological years (1973-2008). The cumulative monthly values of rainfall were studied on an annual and seasonal basis as well as during the arid-dry season. In the deterministic tests, the I.D.W. and R.B.F. check. were inspected, while in the geostatic tests, Ordinary k.iging and Universal k.iging respectively. The selection of the optimum method was made based on the least Root Mean Square Error (R.M.S.E.), as well as on the Mean Error (M.E.), as assessed by the cross validation analysis. The geostatical k.iging also considered the impact of isotropy and anisotropy across all time periods of data collection. Moreover, for Universal k.iging, the study explored spherical, exponential and Gaussian models in various combinations. Geostatistical techniques consistently demonstrated greater reliability than deterministic techniques across all time periods of data collection. Specifically, during the annual period, anisotropy was the prevailing characteristic in geostatistical techniques. Moreover, the results for the irrigation and seasonal periods were generally comparable, with few exceptions where isotropic methods yielded lower (R.M.S.E.) in some seasonal observations.

关键词： Interpolation k.iging I.D.W. Precipitation Greece

Special Relativity’s “Newtonization” in Complex “Para-Space”: The Two Theories Equivalence Question

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Journal of Applied Mathematics and Physics 2024年第7期12卷 2421-2451页

作者： Jerzy k. Filus Department of Mathematics and Computer Science Oakton College Des Plaines IL USA

Complex model, say C3, of “para-space” as alternative to the real M4 Mink.wsk. space-time for both relativistic and classical mechanics was shortly introduced as reference to our previous work. on that subject. The actual aim, however, is an additional analysis of the physical and para-physical phenomena’ behavior as we formally transport observable mechanical phenomena [motion] to non-real interior of the complex domain. As it turns out, such procedure, when properly set, corresponds to transition from relativistic to more classic (or, possibly, just classic) k.nd of the motion. This procedure, we call the “Newtonization of relativistic physical quantities and phenomena”, first of all, includes the mechanical motion’s characteristics in the C3. The algebraic structure of vector spaces was imposed and analyzed on both: the set of all relativistic velocities and on the set of the corresponding to them “Galilean” velocities. The k.y point of the analysis is realization that, as a matter of fact, the relativistic theory and the classical are equivalent at least as for the k.nematics. This conclusion follows the fact that the two defined structures of topological vector spaces i.e., the structure imposed on sets of all relativistic velocities and the structure on set of all “Galilean” velocities, are both diffeomorphic in their topological parts and are isomorphic as the vector spaces. As for the relativistic theory, the two approaches: the hyperbolic (“classical” SR) with its four-vector formalism and Euclidean, where SR is modeled by the complex para-space C3, were analyzed and compared.

关键词： Special Relativity’s Hyperbolic Versus Circular Versions Galilean k.nematics Partial Equivalence of SR and Newton’s Theories Algebra of Relativistic and the Corresponding Galilean Velocities