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Seasonal influence of freshwater discharge on spatio-temporal variations in primary productivity, sea surface temperature, and euphotic zone depth in the northern Bay of Bengal

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Acta Oceanologica Sinica 2024年第6期43卷 1-14页

作者： Hafez Ahmad Felix Jose md.Simul Bhuyan md.Nazrul Islam Padmanava Dash Geosystems Research Institute/department of Geosciences Mississippi State UniversityStarkville 39759USA department of Oceanography University of ChittagongChittagong 4331Bangladesh department of Marine&Earth Sciences Florida Gulf Coast UniversityFort Myers 33965USA Bangladesh Oceanographic Research Institute Cox’s Bazar 4730Bangladesh Faculty of Marine Sciences&Fisheries Institute of Marine SciencesUniversity of ChittagongChittagong 4331Bangladesh department of Geography and Environment Jahangirnagar UniversityDhaka 1342Bangladesh department of Geosciences Mississippi State UniversityStarkville 39759USA

Ocean productivity is the foundation of marine food web,which continuously removes atmospheric carbon dioxide and supports life at sea and on ***-temporal variability of net primary productivity(NPP),sea surface temperature(SST),sea surface salinity(SSS),mixed layer depth(MLD),and euphotic zone depth(EZD) in the northern B ay of Bengal(BoB) during three monsoon seasons were examined in this study based on remote sensing data for the period 2005 to *** compare the NPP distribution between the coastal zones and open BoB,the study area was divided into five zones(Z1-Z5).Results suggest that most productive zones Z2 and Zl are located at the head bay area and are directly influenced by freshwater discharge together with riverine sediment and nutrient *** Z1-Z5,the NPP ranges from 5 315.38 mg/(m^(2)·d) to 346.7 mg/(m^(2)·d)(carbon,since then the same).The highest monthly average NPP of 5 315.38 mg/(m^(2)·d) in February and 5 039.36 mg/(m^(2)·d) in June were observed from Z2,while the lowest monthly average of 346.72 mg/(m^(2)·d) was observed in March from Z4,which is an oceanic *** values vary from 6-154 m for the study area,and it has an inverse correlation with NPP *** is deeper during the summer season and shallower during the wintertime,with a corresponding increase in *** the year,monthly SST shows slight fluctuation for the entire study area,and statistical analysis shows a significant correlation among NPP,and EZD,overall positive between NPP and MLD,whereas no significant correlation among SSS,and SST for the northern ***-term trends in SST and productivity were significantly po sitive in head bay zones but negatively productive in the open *** findings in this study on the distribution of NPP,SST,SSS,MLD,and EZD and their seasonal variability in five different zones of BoB can be used to further improve the management of marine resources and overall environmental condition in response to clim

关键词： chlorophyll a sea surface temperature euphotic zone depth primary productivity Ganges-Brahmaputra ocean color Bay of Bengal monsoon

Polynomials,Higher Order Sobolev Extension Theorems and Interpolation Inequalities on Weighted Folland-Stein Spaces on Stratified Groups

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Acta Mathematica Sinica,English Series 2000年第3期16卷 405-444页

作者： Guozhen Lu department of mathematics,Wayne State university,Detroit,MI 48202,usa department of mathematics Wayne State University Detroit USA

This paper consists of three main *** of them is to develop local and global Sobolev interpolation inequalities of any higher order for the nonisotropic Sobolev spaces on stratified nilpotent Lie *** the extensive research after Jerison’s work[3]on Poincaré-type inequalities for Hrmander’s vector fields over the years,our results given here even in the nonweighted case appear to be *** interpolation inequalities have crucial applications to subelliptic or parabolic PDE’s involving vector *** main tools to prove such inequalities are approximating the Sobolev func- tions by polynomials associated with the left invariant vector fields on *** very useful properties for polynomials associated with the functions are given here and they appear to have independent interests in their own *** the existence of such polynomials is the second main part of this *** results of these two parts have been announced in the author’s paper in Mathematical Research Letters[38]. The third main part of this paper contains extension theorems on anisotropic Sobolev spaces on stratified groups and their applications to proving Sobolev interpolation inequalities on(εδ)domains. Some results of weighted Sobolev spaces are also given *** construct a linear extension operator which is bounded on different Sobolev spaces *** particular,we are able to construct a bounded linear extension operator such that the derivatives of the extended function can be controlled by the same order of derivatives of the given Sobolev *** are stated and proved for weighted anisotropic Sobolev spaces on stratified groups.

关键词： Poincaré inequalities Extension theorems Interpolation inequalities Anisotropic Sobolev spaces A_p weights (ε,δ)domains Vector fields Polynomials on stratified groups

Discrete Calderón-type Reproducing Formula

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Acta Mathematica Sinica,English Series 2000年第2期16卷 277-294页

作者： Yongsheng Han department of mathematics,Auburn university,Auburn,Alabama 36849-5310,usa department of mathematics Auburn University Auburn Alabama 36849-5310 USA

In this paper we use the Calderón-Zygmund operator theory to provide a discrete Calderón- type reproducing *** translation,dilation and,in particular,the Fourier transform are never used in the proofs,all results still hold on spaces of homogeneous type introduced by Coifman and Weiss. As a consequence,we obtain a class of frames with the minimum regularity properties.

关键词： Spaces of homogeneous type Calderón reproducing formula Frame

SYMPLECTIC SCHEMES FOR QUASILINEAR WAVE EQUATIONS OF KLEIN-GORDON AND SINE-GORDON TYPE

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Journal of Computational mathematics 2001年第5期19卷 475-488页

作者： Xiao-wu Lu (department of mathematics and Computer Science, Emory university, Atlanta, GA 30322, usa. Emory university 美国 30322

Presents a class of finite difference methods of first and second order accuracy for the computation of solutions to the quasilinear wave equations. Overview of general symplectic schemes and generating functional; Nu... 详细信息

关键词： Symplectic integration Sine-Gordon equations Finite difference method.

Potential role of tubulin glutamylation in neurodegenerative diseases

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Neural Regeneration Research 2024年第6期19卷 1191-1192页

作者： Abdullah md.Sheikh Shatera Tabassum department of Laboratory Medicine Shimane University Faculty of MedicineShimaneJapan

The differentiation of neuronal stem cells into mature neurons is a complex process that involves both structural and functional *** cells undergo differentiation,there are notable functional changes,including the expression of various transcription factors,cytokines,and ***,structural changes occur as the cells develop various processes from the cell body and establish synaptic contacts with other cells.

关键词： diseases degenerative cytokines

Dynamic Transition and Pattern Formation in Taylor Problem

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Chinese Annals of mathematics,Series B 2010年第6期31卷 953-974页

作者： Tian MA Shouhong WANG department of mathematics Sichuan University Chengdu 610064 China department of mathematics Indiana University Bloomington IN 47405 USA.

The main objective of this article is to study both dynamic and structural transitions of the Taylor-Couette flow, by using the dynamic transition theory and geometric theory of incompressible flows developed recently by the authors. In particular, it is shown that as the Taylor number crosses the critical number, the system undergoes either a continuous or a jump dynamic transition, dictated by the sign of a computable, nondimensional parameter R. In addition, it is also shown that the new transition states have the Taylor vortex type of flow structure, which is structurally stable.

关键词： Taylor problem Couette flow Taylor vortices Dynamic transition theory Dynamic classification of phase transitions Continuous transition Jump transition Mixed transition Structural stability

Rational holomorphic maps from B^2 into B^N with degree 2

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Science China mathematics 2006年第11期49卷 1504-1522页

作者： CHEN Zhihua, Jl Shanyu & XU Dekang department of mathematics, Tongji university, Shanghai 200092, China department of mathematics, university of Houston, Houston, TX 77204, usa department of mathematics Tongji University Shanghai 200092 China department of mathematics University of Houston Houston TX 77204 United States

Rational proper holomorphic maps from the unit ball in C2 into the unit ball CN with degree 2 are studied. Any such map must be equivalent to one of the four types of maps.

关键词： rational holomorphic maps between balls.

Leveraging Sharding-Based Hybrid Consensus for Blockchain

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Computers, Materials and Continua 2024年第1期81卷 1215-1233页

作者： Baageel, Hind Rahman, md Mahfuzur department of Information & Computer Science King Fahd University of Petroleum & Minerals Dhahran 31261 Saudi Arabia Interdisciplinary Research Center (IRC) for Intelligent Secure Systems King Fahd University of Petroleum & Minerals Dhahran 31261 Saudi Arabia

The advent of blockchain technology has transformed traditional methods of information exchange, shifting reliance from centralized data centers to decentralized frameworks. While blockchain's decentralization and security are strengths, traditional consensus mechanisms like Proof ofWork (PoW) and Proof of Stake (PoS) face limitations in scalability. PoW achieves decentralization and security but struggles with scalability as transaction volumes grow, while PoS enhances scalability, but risks centralization due to monopolization by high-stake participants. Sharding, a recent advancement in blockchain technology, addresses scalability by partitioning the network into shards that process transactions independently, thereby improving throughput and reducing latency. However, cross-shard communication, essential for transactions involving multiple shards, introduces challenges in coordination and fault tolerance. This research introduces a shard-based hybrid consensus model, PoSW, which combines PoW and PoS to mitigate the limitations of both mechanisms. By integrating PoW's fairness with PoS's scalability in a shard-based blockchain, the proposedmodel addresses key issues of scalability andmonopolization. We evaluate the model against state-of-the-art consensus algorithms, includingMonoxide and Practical Byzantine Fault Tolerance (PBFT). The results show that the proposed PoSW model reduces communication overhead compared to PBFT and improves resource utilization overMonoxide. In addition to performance gains, the security analysis demonstrates that the PoSW model provides robust defense against common blockchain attacks such as the 51% and Sybil attacks, etc. The proposed approach is particularly suited for applications like decentralized finance (DeFi) and supply chain management, which require both high scalability and robust security. The contributions of this research include the development of the PoSW hybrid consensus mechanism, its comparative evaluation with l

关键词： Decentralized finance

ON THE KINEMATIC GEOMETRY OF MANY BODY SYSTEMS

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Chinese Annals of mathematics,Series B 1999年第1期20卷 11-28页

作者： WU-YI HSIANG(department of mathematics,university of CALIFORNIA,berkeley,CA 94720-3840,usa. Univ Calif Berkeley Dept Math Berkeley CA 94720 USA

In mechanics, both classical and quantum, one studies the profound interaction betweentwo types of energy, namely, the kinetic energy and the potential energy. The former can beorganized as the kinematic metric on the configuration space while the latter can be representedby a suitable potential function, such as the Newtonian potential in celestial mechanics andthe Coulomb potential in quantum mechanics of atomic and molecular physics. In this paper,the author studies the kinematic geometry of n-body systems. The main results are (i) theintroduction of a canonical coordinate svstem which reveals the total amount of kinematicsymmetry by an SO(3) x O(n-1) action in such a canonical coordinate representationt (ii) anin depth analysis of the above kinematic system both in the setting of classical invariant theoryand by the technique of equivariant Riemannian geometry; (iii) a remarkably simple formulafor the potential function in such a canonical coordinate system which reveals the well-fittingbetween the kinematic symmetry and the Potential energy.

关键词： Kinematic geometry Many body system Configuration space