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Calculus bovis inhibits M2 tumor-associated macrophage polarization via Wnt/β-catenin pathway modulation to suppress liver cancer 被引量:1
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作者 Zhen Huang Fan-Ying Meng +12 位作者 Lin-Zhu Lu Qian-Qian Guo Chang-Jun Lv Nian-Hua Tan Zhe Deng Jun-Yi Chen Zi-Shu Zhang Bo Zou Hong-Ping Long Qing Zhou Sha Tian Si Mei Xue-Fei Tian 《World Journal of Gastroenterology》 SCIE CAS 2024年第29期3511-3533,共23页
BACKGROUND Calculus bovis(CB),used in traditional Chinese medicine,exhibits anti-tumor effects in various cancer models.It also constitutes an integral component of a compound formulation known as Pien Tze Huang,which... BACKGROUND Calculus bovis(CB),used in traditional Chinese medicine,exhibits anti-tumor effects in various cancer models.It also constitutes an integral component of a compound formulation known as Pien Tze Huang,which is indicated for the treatment of liver cancer.However,its impact on the liver cancer tumor microenvironment,particularly on tumor-associated macrophages(TAMs),is not well understood.AIM To elucidate the anti-liver cancer effect of CB by inhibiting M2-TAM polarization via Wnt/β-catenin pathway modulation.METHODS This study identified the active components of CB using UPLC-Q-TOF-MS,evaluated its anti-neoplastic effects in a nude mouse model,and elucidated the underlying mechanisms via network pharmacology,transcriptomics,and molecular docking.In vitro assays were used to investigate the effects of CB-containing serum on HepG2 cells and M2-TAMs,and Wnt pathway modulation was validated by real-time reverse transcriptase-polymerase chain reaction and Western blot analysis.RESULTS This study identified 22 active components in CB,11 of which were detected in the bloodstream.Preclinical investigations have demonstrated the ability of CB to effectively inhibit liver tumor growth.An integrated approach employing network pharmacology,transcriptomics,and molecular docking implicated the Wnt signaling pathway as a target of the antineoplastic activity of CB by suppressing M2-TAM polarization.In vitro and in vivo experiments further confirmed that CB significantly hinders M2-TAM polarization and suppresses Wnt/β-catenin pathway activation.The inhibitory effect of CB on M2-TAMs was reversed when treated with the Wnt agonist SKL2001,confirming its pathway specificity.CONCLUSION This study demonstrated that CB mediates inhibition of M2-TAM polarization through the Wnt/β-catenin pathway,contributing to the suppression of liver cancer growth. 展开更多
关键词 calculus bovis M2 tumor-associated macrophage polarization Liver cancer Wnt/β-catenin pathway Tumor microenvironment
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Calculus bovis in hepatocellular carcinoma:Tumor molecular basis,Wnt/β-catenin pathway role,and protective mechanism
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作者 Khaled Mohamed Mohamed Koriem 《World Journal of Gastroenterology》 SCIE CAS 2024年第35期3959-3964,共6页
In this editorial,we comment on the recent article by Huang et al.The editorial focuses specifically on the molecular mechanisms of hepatocellular carcinoma(HCC),mechanism of Wnt/β-catenin pathway in HCC,and protecti... In this editorial,we comment on the recent article by Huang et al.The editorial focuses specifically on the molecular mechanisms of hepatocellular carcinoma(HCC),mechanism of Wnt/β-catenin pathway in HCC,and protective mechanism of Calculus bovis(CB)in HCC.Liver cancer is the fourth most common cause of cancer-related deaths globally.The most prevalent kind of primary liver cancer,HCC,is typically brought on by long-term viral infections(hepatitis B and C),non-alcoholic steatohepatitis,excessive alcohol consumption,and other conditions that can cause the liver to become chronically inflamed and cirrhotic.CB is a wellknown traditional remedy in China and Japan and has been used extensively to treat a variety of diseases,such as high fever,convulsions,and stroke.Disturbances in lipid metabolism,cholesterol metabolism,bile acid metabolism,alcohol metabolism,and xenobiotic detoxification lead to fatty liver disease and liver cirrhosis.Succinate,which is a tricarboxylic acid cycle intermediate,is vital to energy production and mitochondrial metabolism.It is also thought to be a signaling molecule in metabolism and in the development and spread of liver malignancies.The Wnt/β-catenin pathway is made up of a group of proteins that are essential for both adult tissue homeostasis and embryonic development.Cancer is frequently caused by the dysregulation of the Wnt/β-catenin signaling pathway.In HCC liver carcinogenesis,Wnt/β-catenin signaling is activated by the expression of downstream target genes.Communication between the liver and the gut exists via the portal vein,biliary tract,and systemic circulation.This"gutliver axis"controls intestinal physiology.One of the main factors contributing to the development,progression,and treatment resistance of HCC is the abnormal activation of the Wnt/β-Catenin signaling pathway.Therefore,understanding this pathway is essential to treating HCC.Eleven ingredients of CB,particularly oleanolic acid,ergosterol,and ursolic acid,have anti-primary liver cancer properties.Additionally,CB is important in the treatment of primary liver cancer through pathways linked to immune system function and apoptosis.CB also inhibits the proliferation of cancer stem cells and tumor cells and controls the tumor microenvironment.In the future,clinicians may be able to recommend one of many potential new drugs from CB ingredients to treat HCC expression,development,and progress. 展开更多
关键词 Hepatocellular carcinoma MICRORNAS Wnt/β-catenin pathway calculus bovis APOPTOSIS
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From traditional Chinese medicine formulations to effective anticancer agents:Insights from Calculus bovis
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作者 He-Tong Zhao 《World Journal of Gastroenterology》 SCIE CAS 2024年第35期4011-4013,共3页
This editorial examines the therapeutic potential of traditional Chinese medicine(TCM)for aggressive cancers,particularly liver cancer.It highlights the study by Huang et al,which shows how Calculus bovis,a component ... This editorial examines the therapeutic potential of traditional Chinese medicine(TCM)for aggressive cancers,particularly liver cancer.It highlights the study by Huang et al,which shows how Calculus bovis,a component of the TCM Pien Tze Huang,suppresses liver cancer by inhibiting M2 macrophage polarization via the Wnt/β-catenin pathway.This research emphasizes the importance of transitioning from effective TCM formulations to isolating active components and understanding their mechanisms.While the study provides valuable insights,it primarily focuses on the Wnt/β-catenin pathway and does not delve deeply into the mechanisms of individual components.Future research should aim to comprehensively study these components,explore their interactions,and validate findings through clinical trials.This approach will integrate traditional wisdom with modern scientific validation,advancing the development of innovative cancer treatments based on TCM formulations. 展开更多
关键词 calculus bovis Traditional Chinese medicine Liver cancer Tumor microenvironment M2 tumor-associated macrophages Wnt/β-catenin pathway
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Pixel’s Quantum Image Enhancement Using Quantum Calculus
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作者 Husam Yahya Dumitru Baleanu +1 位作者 Rabha W.Ibrahim Nadia M.G.Al-Saidi 《Computers, Materials & Continua》 SCIE EI 2023年第2期2531-2539,共9页
The current study provides a quantum calculus-based medical image enhancement technique that dynamically chooses the spatial distribution of image pixel intensity values.The technique focuses on boosting the edges and... The current study provides a quantum calculus-based medical image enhancement technique that dynamically chooses the spatial distribution of image pixel intensity values.The technique focuses on boosting the edges and texture of an image while leaving the smooth areas alone.The brain Magnetic Resonance Imaging(MRI)scans are used to visualize the tumors that have spread throughout the brain in order to gain a better understanding of the stage of brain cancer.Accurately detecting brain cancer is a complex challenge that the medical system faces when diagnosing the disease.To solve this issue,this research offers a quantum calculus-based MRI image enhancement as a pre-processing step for brain cancer diagnosis.The proposed image enhancement approach improves images with low gray level changes by estimating the pixel’s quantum probability.The suggested image enhancement technique is demonstrated to be robust and resistant to major quality changes on a variety ofMRIscan datasets of variable quality.ForMRI scans,the BRISQUE“blind/referenceless image spatial quality evaluator”and the NIQE“natural image quality evaluator”measures were 39.38 and 3.58,respectively.The proposed image enhancement model,according to the data,produces the best image quality ratings,and it may be able to aid medical experts in the diagnosis process.The experimental results were achieved using a publicly available collection of MRI scans. 展开更多
关键词 Quantum calculus MRI brain cancer image enhancement image processing BRISQUE NIQE
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A Vector Tensor Calculus Description of a Euclidean Space
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作者 Pavel Grinfeld 《Journal of Applied Mathematics and Physics》 2023年第3期705-720,共16页
We present a tensor description of Euclidean spaces that emphasizes the use of geometric vectors which leads to greater geometric insight and a higher degree of organization in analytical expressions. We demonstrate t... We present a tensor description of Euclidean spaces that emphasizes the use of geometric vectors which leads to greater geometric insight and a higher degree of organization in analytical expressions. We demonstrate the effectiveness of the approach by proving a number of integral identities with vector integrands. The presented approach may be aptly described as absolute vector calculus or as vector tensor calculus. 展开更多
关键词 Tensor calculus Differential Geometry Embedded Surfaces and Curves Scalar Curvature Gaussian Curvature
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External Equality and Absolute Equality Coincide in Finite CCS and π Calculus Without Summation
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作者 金云 《Journal of Shanghai Jiaotong university(Science)》 EI 2011年第5期533-537,共5页
External equality and absolute equality are defined model independently by Fu. It is interesting and important to know whether these two equalities coincide or not. There are some results in Fu's paper for this is... External equality and absolute equality are defined model independently by Fu. It is interesting and important to know whether these two equalities coincide or not. There are some results in Fu's paper for this issue. It is relatively easy to prove the coincidence if the summation operator is in the language, otherwise it is harder. In fact Fu proposed it as an open problem whether the two equalities coincide in some languages without summation. In this paper, the proofs of the coincidence in finite CCS and π calculus without summation are given. 展开更多
关键词 CCS calculus π calculus absolute equality external equality coincidence
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GLOBAL SOLUTIONS IN THE CRITICAL SOBOLEV SPACE FOR THE LANDAU EQUATION
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作者 Hao WANG 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1347-1372,共26页
The Landau equation is studied for hard potential with-2≤γ≤1.Under a perturbation setting,a unique global solution of the Cauchy problem to the Landau equation is established in a critical Sobolev space H_(x)^(d)L_... The Landau equation is studied for hard potential with-2≤γ≤1.Under a perturbation setting,a unique global solution of the Cauchy problem to the Landau equation is established in a critical Sobolev space H_(x)^(d)L_(v)^(2)(d>3/2),which extends the results of[11]in the torus domain to the whole space R_(x)^(3).Here we utilize the pseudo-differential calculus to derive our desired result. 展开更多
关键词 Landau equation nonlinear energy method global existence pseudo-differential calculus
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THE GLOBAL EXISTENCE OF STRONG SOLUTIONS FOR A NON-ISOTHERMAL IDEAL GAS SYSTEM
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作者 韩斌 赖宁安 Andrei TARFULEA 《Acta Mathematica Scientia》 SCIE CSCD 2024年第3期865-886,共22页
We investigate the global existence of strong solutions to a non-isothermal ideal gas model derived from an energy variational approach.We first show the global wellposedness in the Sobolev space H^(2)(R^(3)) for solu... We investigate the global existence of strong solutions to a non-isothermal ideal gas model derived from an energy variational approach.We first show the global wellposedness in the Sobolev space H^(2)(R^(3)) for solutions near equilibrium through iterated energy-type bounds and a continuity argument.We then prove the global well-posedness in the critical Besov space B^(3/2)_(2,1) by showing that the linearized operator is a contraction mapping under the right circumstances. 展开更多
关键词 thermal fluid equations energy-variational method well-posedness theory for PDE paraproduct calculus
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F-fuzzy Calculus System
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作者 潘无名 王俊卿 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第1期59-64,共6页
A formalized calculus system called F_fuzzy calculus system, which is a symbol deduction system to formalize fuzzy inference, is constructed in this paper. The fuzzy modus ponens was completely formalized in this calc... A formalized calculus system called F_fuzzy calculus system, which is a symbol deduction system to formalize fuzzy inference, is constructed in this paper. The fuzzy modus ponens was completely formalized in this calculus system. 展开更多
关键词 fuzzy inference fuzzy formal deduction F_fuzzy calculus system
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Using laparoscope to remove an ectopic intrauterine device in the anterior wall of urinary bladder:A case report
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作者 Shi-Xue Liu Xing-You Dong 《World Journal of Clinical Cases》 SCIE 2024年第17期3221-3225,共5页
BACKGROUND An intrauterine device(IUD)is a contraceptive device placed in the uterine cavity and is a common contraceptive method for Chinese women.However,an IUD may cause complications due to placement time,intraute... BACKGROUND An intrauterine device(IUD)is a contraceptive device placed in the uterine cavity and is a common contraceptive method for Chinese women.However,an IUD may cause complications due to placement time,intrauterine pressure and other factors.Ectopic IUDs are among the most serious complications.Ectopic IUDs are common in the myometrium and periuterine organs,and there are few reports of ectopic IUDs in the urinary bladder,especially in the anterior wall.CASE SUMMARY A 52-year-old woman was hospitalized due to a urinary bladder foreign body found via abdominal ultrasound and computed tomography(CT)examination.The patient had a 2-year history of recurrent abdominal distension and lower abdominal pain,accompanied by frequent urination,urgency,dysuria and other discomfort.Ultrasound examination revealed foreign bodies in the bladder cavity,with calculus on the surface of the foreign bodies.CT revealed a circular foreign body on the anterior wall of the urinary bladder,suggesting the possibility of an ectopic IUD.After laparoscopic exploration,an annular IUD was found in the anterior wall of urinary bladder,and an oval calculus with a diameter of approximately 2 cm was attached to the surface of the bladder cavity.The IUD and calculus were successfully and completely removed.The patient recovered well after surgery.CONCLUSION Abdominal ultrasound and CT are effective methods for detecting ectopic IUDs.The IUD is located in the urinary bladder and requires early surgical treatment.The choice of surgical method is determined by comprehensively considering the depth of the IUD in the bladder muscle layer,the situation of complicated calculus,the situation of intravesical inflammation and medical technology and equipment. 展开更多
关键词 Intrauterine device ECTOPIC Anterior wall of the urinary bladder calculus LAPAROSCOPE Case report
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Unveiling the anticancer effect of traditional Chinese herbal medicine
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作者 Naoki Asano 《World Journal of Gastroenterology》 SCIE CAS 2024年第30期3625-3627,共3页
In this issue of World Journal of Gastroenterology,Huang et al reported that Calculus bovis(CB),a traditional Chinese herbal medicine,impedes the growth of liver cancers in vivo.Through further in vitro studies,they s... In this issue of World Journal of Gastroenterology,Huang et al reported that Calculus bovis(CB),a traditional Chinese herbal medicine,impedes the growth of liver cancers in vivo.Through further in vitro studies,they showed that CB suppressed the M2 polarization of tumor-associated macrophages by suppressing the Wnt signaling pathway,which consequently inhibited the growth of liver cancer.Although the effects of traditional Chinese herbal medicine are often not scientifically proven,Huang et al successfully identified the molecular mechanism involved in the anticancer effect of CB,and it is anticipated that the molecular mechanisms involved in the effects of other traditional Chinese herbal medicines will be scientifically elucidated,as demonstrated in this article. 展开更多
关键词 calculus bovis Chinese herbal medicine WNT Hepatocellular carcinoma Liver cancer Tumor-associated macrophages M2 polarization
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Fault Diagnosis Method of Rolling Bearing Based on ESGMD-CC and AFSA-ELM
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作者 Jiajie He Fuzheng Liu +3 位作者 Xiangyi Geng Xifeng Liang Faye Zhang Mingshun Jiang 《Structural Durability & Health Monitoring》 EI 2024年第1期37-54,共18页
Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and relia... Incomplete fault signal characteristics and ease of noise contamination are issues with the current rolling bearing early fault diagnostic methods,making it challenging to ensure the fault diagnosis accuracy and reliability.A novel approach integrating enhanced Symplectic geometry mode decomposition with cosine difference limitation and calculus operator(ESGMD-CC)and artificial fish swarm algorithm(AFSA)optimized extreme learning machine(ELM)is proposed in this paper to enhance the extraction capability of fault features and thus improve the accuracy of fault diagnosis.Firstly,SGMD decomposes the raw vibration signal into multiple Symplectic geometry components(SGCs).Secondly,the iterations are reset by the cosine difference limitation to effectively separate the redundant components from the representative components.Additionally,the calculus operator is performed to strengthen weak fault features and make them easier to extract,and the singular value decomposition(SVD)weighted by power spectrum entropy(PSE)can be utilized as the sample feature representation.Finally,AFSA iteratively optimized ELM is adopted as the optimized classifier for fault identification.The superior performance of the proposed method has been validated by various experiments. 展开更多
关键词 Symplectic geometry mode decomposition calculus operator cosine difference limitation fault diagnosis AFSAELM model
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Review on Service Curves of Typical Scheduling Algorithms
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作者 GAO Yuehong NING Zhi +4 位作者 HE Jia ZHOU Jinfei GAO Chenqiang TANG Qingkun YU Jinghai 《ZTE Communications》 2024年第2期55-70,共16页
In recent years,various internet architectures,such as Integrated Services(IntServ),Differentiated Services(DiffServ),Time Sensitive Networking(TSN)and Deterministic Networking(DetNet),have been proposed to meet the q... In recent years,various internet architectures,such as Integrated Services(IntServ),Differentiated Services(DiffServ),Time Sensitive Networking(TSN)and Deterministic Networking(DetNet),have been proposed to meet the quality-of-service(QoS)requirements of different network services.Concurrently,network calculus has found widespread application in network modeling and QoS analysis.Network calculus abstracts the details of how nodes or networks process data packets using the concept of service curves.This paper summarizes the service curves for typical scheduling algorithms,including Strict Priority(SP),Round Robin(RR),Cycling Queuing and Forwarding(CQF),Time Aware Shaper(TAS),Credit Based Shaper(CBS),and Asynchronous Traffic Shaper(ATS).It introduces the theory of network calculus and then provides an overview of various scheduling algorithms and their associated service curves.The delay bound analysis for different scheduling algorithms in specific scenarios is also conducted for more insights. 展开更多
关键词 network calculus service curve scheduling algorithm QOS
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A Dark Energy Hypothesis I
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作者 James Togeas 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第3期1138-1141,共4页
The cosmological constant, Λ, represents dark energy. The dark energy hypothesis (DEH) replaces Λ with a variable quantity, the cosmological parameter: Λ=1a2η2In this formula, “a” is the scale factor and η the ... The cosmological constant, Λ, represents dark energy. The dark energy hypothesis (DEH) replaces Λ with a variable quantity, the cosmological parameter: Λ=1a2η2In this formula, “a” is the scale factor and η the conformal time: adη = cdt. A companion paper (DEH II) develops and explores a cosmological model with this variable parameter. This paper portrays the origin of the cosmological parameter in the uncoupling of time and space in the early universe from a prior state in which the comoving coordinates x0 = η and x1 = χ, the cosmic latitude, are coupled. In this hypothesis dark matter is a co-product of the decoupling, but its nature remains mysterious. 展开更多
关键词 Dark Energy Dark Matter Cosmological Constant Tensor calculus
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Variational Approach to Heat Conduction Modeling
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作者 Slavko Đurić Ivan Aranđelović Milan Milotić 《Journal of Applied Mathematics and Physics》 2024年第1期234-248,共15页
It is known that Fourier’s heat equation, which is parabolic, implies an infinite velocity propagation, or, in other words, that the mechanism of heat conduction is established instantaneously under all conditions. T... It is known that Fourier’s heat equation, which is parabolic, implies an infinite velocity propagation, or, in other words, that the mechanism of heat conduction is established instantaneously under all conditions. This is unacceptable on physical grounds in spite of the fact that Fourier’s law agrees well with experiment. However, discrepancies are likely to occur when extremely short distances or extremely short time intervals are considered, as they must in some modern problems of aero-thermodynamics. Cattaneo and independently Vernotte proved that such process can be described by Heaviside’s telegraph equation. This paper shows that this fact can be derived using calculus of variations, by application of the Euler-Lagrange equation. So, we proved that the equation of heat conduction with finite velocity propagation of the thermal disturbance can be obtained as a solution to one variational problem. 展开更多
关键词 Telegraph Equation Heat Equation Heat Conduction calculus of Variations
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The Absence of “Perfect Induction”in the Science
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第5期1930-1947,共18页
The present paper is finalized to show that the Science, even if considered in its two different Phenomenological Approaches at present known, is unable to assert that: “Thinks are like that”. This is because both t... The present paper is finalized to show that the Science, even if considered in its two different Phenomenological Approaches at present known, is unable to assert that: “Thinks are like that”. This is because both the two Scientific Approaches previously mentioned have not the property of “the perfect induction”. Consequently, although they can even reach an experimental confirmation of the theoretical results, and thus a “valid description” of the various phenomena of the surrounding world, such a description has not an “absolute value”. In fact, it always and only has an “operative validity”, that is, it exclusively and solely refers to an “experimental point of view”. This means that such an “operative validity” cannot represent the basis for a logical process characterized by a “perfect induction”. In addition, the Traditional Scientific Approach is also characterized by “Insoluble” Problems, “Intractable Problems”, Problems with “drifts”, which could generally be termed as “side effects”. On the other hand, the same com-possible Scientific Approach based on the Emerging Quality of Self-Organizing Systems, also presents its “Emerging Exits”. Consequently, none of the two mentioned scientific Approaches has the “gift” of “the perfect induction”. However, there are significant differences between the two. Differences that may “suggest” the most appropriate choice among them for an “operative point of view”. This conclusion will be com-proved by considering, with particular reference, both the “side effects”, which are related to the Traditional Approach and, on the other hand, the “Emerging Exits”, which specifically pertain to the new Scientific Approach based on the Emerging Quality of Self-Organizing Systems. 展开更多
关键词 Perfect Induction Maximum Ordinality Principle Incipient Differential calculus
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Elements of Electromagnetic Matter
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作者 Viktor Ariel 《Journal of Modern Physics》 2024年第3期250-270,共21页
Originally, Maxwell attempted to express his electromagnetic theory using four-dimensional mathematics of quaternions. Maxwell’s equations were later re-written in a three-dimensional real vector form, which is how t... Originally, Maxwell attempted to express his electromagnetic theory using four-dimensional mathematics of quaternions. Maxwell’s equations were later re-written in a three-dimensional real vector form, which is how the theory is presented today. Thus, an interesting question remains whether we can derive electromagnetic equations analytically from the basic mathematical principles of quaternion algebra and calculus, resulting in general and analytic matter equations. This question seems highly intriguing. Previously, we developed a mathematical theory of time using a normed division algebra of real quaternions [1]. In this study, we extend the theory of time by presenting a new analytical derivation of electromagnetic matter equations using the calculus of real quaternions, as originally intended by Maxwell. Therefore, we propose a novel mathematical definition of the quaternion path derivative using the properties of quaternion division. We then apply the quaternion derivative to an external electromagnetic potential and assume that the first quaternion derivative represents the quaternion electromagnetic force. Next, we assume that the second derivative, or quaternion Laplacian operator, applied to an external electromagnetic potential leads to the quaternion electromagnetic current density. The new analytical expressions are similar to the original empirical Maxwell equations, except for an additional scalar electric field, which allows for a novel formulation of Ohm’s conductivity law. We demonstrate that the resulting analytical equations can be written equivalently using either electromagnetic potentials or fields. Finally, we summarize the key postulates and equations of the new electromagnetic matter theory, which were based on normed division algebra and the calculus of quaternions. The resulting theory appears to be a useful analytical enhancement of the original Maxwell equations, and therefore, seems highly comprehensive, logical, and compelling. 展开更多
关键词 Maxwell’s Equations Relativistic Electrodynamics Quaternion calculus
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The Accelerated Expansion of the Universe in the Light of the Maximum Ordinality Principle
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2024年第2期585-602,共18页
The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in pa... The main aim of the paper is to present (and at the same time offer) a differ-ent perspective for the analysis of the accelerated expansion of the Universe. A perspective that can surely be considered as being “in parallel” to the tradition-al ones, such as those based, for example, on the hypotheses of “Dark Matter” and “Dark Energy”, or better as a “com-possible” perspective, because it is not understood as being “exclusive”. In fact, it is an approach that, when con-firmed by experimental results, always keeps its validity from an “operative” point of view. This is because, in analogy to the traditional perspectives, on the basis of Popper’s Falsification Principle the corresponding “Generative” Logic on which it is based has not the property of the perfect induction. The basic difference then only consists in the fact that the Evolution of the Universe is now modeled by considering the Universe as a Self-Organizing System, which is thus analyzed in the light of the Maximum Ordinality Principle. 展开更多
关键词 Accelerated Expansion of the Universe Maximum Ordinality Principle Incip-ient Differential calculus
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Variational Approach to 2D and 3D Heat Conduction Modeling
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作者 Slavko Đurić Ivan Aranđelović Milan Milotić 《Journal of Applied Mathematics and Physics》 2024年第4期1383-1400,共18页
The paper proposes an approximate solution to the classical (parabolic) multidimensional 2D and 3D heat conduction equation for a 5 × 5 cm aluminium plate and a 5 × 5 × 5 cm aluminum cube. An approximat... The paper proposes an approximate solution to the classical (parabolic) multidimensional 2D and 3D heat conduction equation for a 5 × 5 cm aluminium plate and a 5 × 5 × 5 cm aluminum cube. An approximate solution of the generalized (hyperbolic) 2D and 3D equation for the considered plate and cube is also proposed. Approximate solutions were obtained by applying calculus of variations and Euler-Lagrange equations. In order to verify the correctness of the proposed approximate solutions, they were compared with the exact solutions of parabolic and hyperbolic equations. The paper also presents the research on the influence of time parameters τ as well as the relaxation times τ ∗ to the variation of the profile of the temperature field for the considered aluminum plate and cube. 展开更多
关键词 Classical Equation of Heat Conduction Generalized Equation of Heat Conduction calculus of Variations Approximate Solution
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一本有新意的微积分教材——评美国MIT教授Strang新编《CALCULUS》
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作者 向隆万 《大学数学》 1994年第S2期16-22,共7页
微积分教材数以千计,每年都有不少新作问世,但有新意者却如凤毛麟角。91年夏我到美国参加第二届国际工业与应用数学大会(ICIAM’91),在大会展厅看到美国麻省理工学院(MIT)数学系教授、美国工业与应用数学学会(SIAM)教育委员会主席Stran... 微积分教材数以千计,每年都有不少新作问世,但有新意者却如凤毛麟角。91年夏我到美国参加第二届国际工业与应用数学大会(ICIAM’91),在大会展厅看到美国麻省理工学院(MIT)数学系教授、美国工业与应用数学学会(SIAM)教育委员会主席Strang教授刚刚出版的《CALCULUS》,很有特色,会后应邀访问MIT。 展开更多
关键词 calculus Strang 微积分教学 国际工业 一致连续 教材分析 部分分式 闭区间 无穷小量 换元法
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