Point Principle Research Articles

A variational framework for Cahn–Hilliard-type diffusion coupled with Allen–Cahn-type multi-phase transformations in elastic and dissipative solids

This article presents a variational framework for coupled chemo-mechanical solids undergoing irreversible micro-structural changes at infinitesimal strains. The coupled problem is characterised by phenomena such as phase transitions, micro-structure coarsening and swelling. It is an extension of our previous work on variational inelasticity for a conserved chemo-mechanical setting to a unified conserved and non-conserved setting which include multi-phase transformations. The variational framework, again governed by continuous-time, discrete-time and discrete-space–time incremental variational principles, is outlined for coupled diffusion-phase transformation phenomena in elastic and dissipative solids. For the sake of simplicity, focus is restricted to isothermal conditions. It is shown that the governing macro- and micro-balance equations of the coupled problem appear as Euler equations of these minimisation and saddle point principles. In contrast to our previous work, extended variational principles (with the gradient of the chemical potential and phase fractions) are constructed that account for diffusion-phase transformation coupling. This is achieved by Legendre transformations. Note that the local–global solution strategy is still preserved and the resulting system of symmetric non-linear algebraic equations are solved by Newton–Raphson-type iterative methods. The applicability of the proposed framework is demonstrated by numerical simulations that qualitatively characterise lower bainitic micro-structure.

Global trends in acupuncture research: A scientometric analysis from 1980 to 2023.

The objective of this study was to examine articles on acupuncture from past to present, revealing prevalent research trends, showcasing global productivity, identifying international collaborations, and highlighting influential publications and journals in the field. We acquired a comprehensive dataset comprising 9340 articles pertaining to acupuncture that were published within the time frame spanning from 1980 to 2023. These articles were sourced from the Web of Science and underwent rigorous analysis through a diverse set of bibliometric techniques. Our analytical approaches encompassed trend keyword analysis, thematic evolution analysis, conceptual structure analysis, factor analysis, citation and co-citation analyses, as well as an exploration of international collaboration patterns. The 3 most productive countries were China (n = 3357), the USA (n = 1351), and South Korea (n = 814). The 3 most productive journals were Acupuncture in Medicine (n = 440), Evidence Based Complementary and Alternative Medicine (n = 415), and Medical Acupuncture (n = 400). The 3 journals with the highest h-index on acupuncture were the Journal of Alternative and Complementary Medicine (h = 45), Pain (h = 41), and the American Journal of Chinese Medicine (h = 35). The most active author was Park Hi-Joon (n = 128). According to the findings of the factor analysis, acupuncture literature was grouped around 3 main subfactors. The primary factor encompassed topics related to the effectiveness/applicability of the treatment method for various medical conditions and general principles of acupuncture methods and points. The second factor covered topics related to mental health and quality of life. The third subfactor addressed the qualitative and quantitative analysis direction of acupuncture, such as meta-analysis and systematic reviews, and randomized controlled trials. From the past to the present, the most extensively researched main topics in acupuncture literature have covered a wide range of subjects. Prominent themes among these topics included acupuncture methods and applications, pain management, the nervous system and acupuncture, mental health and acupuncture, quality of life, and general health. In recent years, emerging trends in acupuncture research have focused on neurological health issues, oncology and cancer treatment, women's health and hormonal issues, sleep problems, digestive issues, and studies related to the quantitative and qualitative evaluation of acupuncture research.

Patient regional index: a new way to rank clinical specialties based on outpatient clinics big data

BackgroundMany existing healthcare ranking systems are notably intricate. The standards for peer review and evaluation often differ across specialties, leading to contradictory results among various ranking systems. There is a significant need for a comprehensible and consistent mode of specialty assessment.MethodsThis quantitative study aimed to assess the influence of clinical specialties on the regional distribution of patient origins based on 10,097,795 outpatient records of a large comprehensive hospital in South China. We proposed the patient regional index (PRI), a novel metric to quantify the regional influence of hospital specialties, using the principle of representative points of a statistical distribution. Additionally, a two-dimensional measure was constructed to gauge the significance of hospital specialties by integrating the PRI and outpatient volume.ResultsWe calculated the PRI for each of the 16 specialties of interest over eight consecutive years. The longitudinal changes in the PRI accurately captured the impact of the 2017 Chinese healthcare reforms and the 2020 COVID-19 pandemic on hospital specialties. At last, the two-dimensional assessment model we devised effectively illustrates the distinct characteristics across hospital specialties.ConclusionWe propose a novel, straightforward, and interpretable index for quantifying the influence of hospital specialties. This index, built on outpatient data, requires only the patients’ origin, thereby facilitating its widespread adoption and comparison across specialties of varying backgrounds. This data-driven method offers a patient-centric view of specialty influence, diverging from the traditional reliance on expert opinions. As such, it serves as a valuable augmentation to existing ranking systems.

Application of Hazard Analysis Critical Control Point (HACCP) principles to beef mortadella production

A mortadella is a cooked sausage made from raw pork, beef, chicken or lamb. It is popular in Jordan and neighboring countries for its taste, texture, nutritional value and ease of inclusion in sandwiches. The product is sold in plastic packaging, in circular rolls or vacuum packed. Although it poses no serious threat to human health, the heat can be dangerous if used improperly. A HACCP system is used to manage the production process, with a focus on quality control (CCP) throughout the manufacturing phase. Safety risks are identified at all stages of production, from raw materials to storage and distribution. Foodborne illnesses are primarily caused by pathogenic microorganisms, and these raw materials include pathogenic plant cells, Bacillus cereus, Clostridium botulinum and Clostridium perfringens that survive after cooking and contamination detected after monitoring. Post-manufacturing controls are performed through Good Manufacturing Practices (GMPs). The objectives of the study were to identify potential hazards associated with the production of beef mortadella, determine the CCPs to be implemented, develop a monitoring plan and establish corrective action on a case-by-case basis. The HACCP plan was developed in collaboration with local stakeholders and follows a process flow diagram to identify potential hazards and preventive measures. The system includes the steps for obtaining and storing the ingredients, preparing the meat, adding non-meat ingredients, and transferring the raw mixture to an incubator. The meat is weighed and filled with the mixture to improve cleanliness and avoid excess nitrite. The storage time between incubation and cooking is controlled to allow bacteria to multiply. To kill plant pathogens and reduce the total number of microorganisms, the product is cooked in a steam oven at 75°C for 5 minutes. The aim of the cooking process is to reduce microbial growth before lethal temperatures have been reached and uniform heating of the product has been ensured. Cooking suitability is checked by thermographic records and visual inspection of the cooked product. The plan also includes personnel in charge of every stage of production, ensuring a clean and hygienic environment. Key words: HACCP, Mortadella, meat processing, hygiene control, food safety

A fixed point principle for some nonself operators on large Kasahara spaces

A fixed point principle for some nonself operators on large Kasahara spaces

Optimal boundary control for a competitive population system with size structure and time delay in a polluted environment

In this paper, we consider the optimal boundary control problem of a two-species competitive system with time delay and size structure in a polluted environment. First, the well posedness of the system is studied by using the characteristic line method and the fixed point principle. Second, the necessary conditions for optimal boundary control are obtained by conjugate system and normal cone property. Finally, the existence and uniqueness of the optimal strategy are proved by Ekeland variational principle.

Quantum phase transition and absence of quadratic divergence in generalized quantum field theories

In ordinary thermodynamics, around first-order phase transitions, the intensive parameters such as temperature and pressure are automatically fixed to the phase transition point when one controls the extensive parameters such as total volume and total energy. From the microscopic point of view, the extensive parameters are more fundamental than the intensive parameters. Analogously, in conventional quantum field theory (QFT), coupling constants (including masses) in the path integral correspond to intensive parameters in the partition function of the canonical formulation. Therefore, it is natural to expect that, in a more fundamental formulation of QFT, coupling constants are dynamically fixed , just as the intensive parameter in the microcanonical formulation. Here, we demonstrate that the automatic tuning of the coupling constants is realized at a quantum phase transition point at zero temperature, even when the transition is of higher order, due to the Lorentzian nature of the path integral. This naturally provides a basic foundation for the multicritical point principle. As a concrete toy model for solving the Higgs hierarchy problem, we study how the mass parameter is fixed in the ϕ4 theory at the one-loop level in the microcanonical or further generalized formulation of QFT. We find that there are two critical points for the renormalized mass: zero and of the order of ultraviolet cutoff. In the former, the Higgs mass is automatically tuned to be zero and thus its fine-tuning problem is solved. We also show that the quadratic divergence is absent in a more realistic two-scalar model that realizes the dimensional transmutation. Additionally, we explore the possibility of fixing quartic coupling in ϕ4 theory and find that it can be fixed to a finite value. Published by the American Physical Society 2024

Novel UV Spectrophotometric approaches for the concurrent determination of Teneligliptin and Metformin in Tablet Formulation

In the study simultaneous assessment of teneligliptin hydrobromide hydrate and metformin hydrochloride in tablets were developed and validated by four new UV spectroscopic approaches. The ratio difference approach was used to measure the variation in two selected amplitudes of ratio spectra, and the regression equation was employed to determine the amounts of pharmaceuticals. The second approach, known as the first derivative of ratio spectra approach, the UV spectra were transformed into their ratio spectra and corresponding first derivatives, and the first-derivative signal was gauged at 275 and 226.2 nm for metformin hydrochloride and teneligliptin hydrobromide hydrate, sequentially, making use of 2 nm as the wavelength interval (Δλ) and a factor of 1 as a scaling factor, respectively. Whereas absorbance subtraction method works with the principle of finding isosbestic point and calculating absorption factor. The fourth approach, known as the dual wavelength method, relies on computing the absorbance difference at two different wavelengths where the other drug has same absorbance. Linearity and range, specificity, accuracy, precision, limit of detection and quantification were among the criteria evaluated during validation of the new methods in agreement with ICH recommendations and found to be within the permitted limits. For both the medicines, a linear response was observed in all four methods over the concentration sequence of 2-12 µg/ml. Therefore, the proposed methodologies may be successfully used for the concurrent evaluation of teneligliptin hydrobromide hydrate and metformin hydrochloride in tablet form.

On solutions vanishing at infinity of infinite systems of quadratic Urysohn integral equations

The paper is devoted to present a result on the existence of solutions of an infinite system of quadratic integral equations of the Urysohn type considered on the real half-axis. Our investigations are conducted in the Banach space consisting of bounded and continuous functions defined on the real half-axis with values in the space of real sequences converging to zero. That space is equipped with the standard supremum norm. The main tools used in our study is the technique of measures of noncompactness and the Schauder fixed point principle. We illustrate our result by a suitable example.

Vehicle suspension tuning for bridge-friendliness and influence on coupled vehicle-bridge system frequency

A novel study on the mitigation of bridge response via tuning of vehicle suspension parameters is presented. The coupled vehicle-bridge interaction (VBI) system consists of a quarter car model with a semi-active skyhook suspension. Transmissibility functions of the time-varying VBI system are derived and an extended fixed points principle is applied to obtain optimally tuned values of the vehicle suspension parameters for bridge-friendliness. Performances of both the optimally tuned passive and semi-active suspensions are assessed in terms of the dynamic responses, energetics and interacting force of the VBI system, and are shown to achieve excellent bridge-friendliness. Effects of vehicle suspension parameters on the temporal variation of the coupled bridge frequency are also studied. It is found that the bridge frequency depends strongly on two key physical parameters: vehicle-bridge frequency ratio and vehicle damping ratio. Moreover, variations of the bridge frequency during the vehicle passage are small when the tuned suspensions are used. This new finding may have critical implications in future research in bridge frequency identification using a moving vehicle.

A new model construction by making a detour via intuitionistic theories IV: A closer connection between KPω and BI

By combining tree representation of sets with the method introduced in the previous three papers I–III [39,35,37] in the series, we give a new Π21-preserving interpretation of KPωr+(Πn+2-Found)+θ (Kripke–Platek set theory with the foundation schema restricted to Πn+2, and augmented by θ) in Σ11-AC0+(Πn+21-TI)+θ for any Π21 sentence θ, where the language of second order arithmetic is considered as a sublanguage of that of set theory via the standard interpretation. Thus the addition of any Π21 theorem of BI≡Σ11-AC0+(Π∞1-TI) does not increase the consistency strength of KPω. Among such Π21 theorems are several fixed point principles for positive arithmetical operators and ω-model reflection (the cofinal existence of coded ω-models) for theorems of BI. The reader's familiarity to the previous works I–III in the series might help, but is not necessary.

Acupoints for Headache with Blood Stasis Syndrome: a Literature Study Based on Data Mining Technology.

This study aimed to investigate the features and underlying principles of acupuncture points used in the treatment of headaches associated with blood stasis syndrome. Literature on the treatment of blood stasis headache with acupuncture and moxibustion was searched across three Chinese databases and one English database from January 1st, 2000, to January 1st, 2024. Relevant data including titles, journals, authors, keywords, interventions, main acupoints, and outcomes were extracted for further analysis. A total of 112 papers with 102 complete prescriptions were analyzed. Of the 77 acupoints examined, 72 were meridian points, and 5 were extraordinary points, used 699 times in total. The top ten acupoints by frequency were Fengchi (GB20), Taiyang (EX-HN5), Baihui (GV20), Hegu (LI4), Shuaigu (GB8), Taichong (LR3), Xuehai (SP10), Touwei (ST8), Geshu (BL17), and Waiguan (TE5). Yang meridian points were used more frequently than Yin meridian points (82.8% vs 17.2%), with the Gallbladder Meridian of Foot Shaoyang being the most common. Nearly half of the acupoints (49.9%) were on the head and neck, and 23.1% on the lower limbs. Specific acupoints accounted for 53.5% of the total frequency. Fengchi (GB20) and Taiyang (EX-HN5) showed the highest correlation. Association rule mining highlighted combinations like Fengchi (GB20) with Taiyang (EX-HN5) and Baihui (GV20). Cluster analysis yielded five clusters. The study provides insights into selecting effective acupoints and combinations for clinical acupuncture practice and experimental studies in treating blood stasis headaches. Acupoints like Fengchi (GB20), Taiyang (EX-HN5), and Baihui (GV20) may be effective for clinical treatment, but further studies are needed to validate their efficacy.

Local well-posedness results for the nonlinear fractional diffusion equation involving a Erdélyi-Kober operator

<p>In this paper, we study an initial boundary value problem of a nonlinear fractional diffusion equation with the Caputo-type modification of the Erdélyi-Kober fractional derivative. The main tools are the Picard-iteration method, fixed point principle, Mittag-Leffler function, and the embedding theorem between Hilbert scales spaces and Lebesgue spaces. Through careful analysis and precise calculations, the priori estimates of the solution and the smooth effects of the Erdélyi-Kober operator are demonstrated, and then the local existence, uniqueness, and stability of the solution of the nonlinear fractional diffusion equation are established, where the nonlinear source function satisfies the Lipschitz condition or has a gradient nonlinearity.</p>

Optimized zone-based vehicle speed estimation and classification

Abstract. This article pioneers the fusion of advanced computer vision, and environmental science in order to be a starting point in ecological tasks and environmental benefits. Utilizing state-of-the-art tools like YOLOv7 and innovative algorithms, the study achieves unmatched accuracy in vehicle identification, classification, tracking, and speed analysis. By optimizing YOLOv7-e6e-1280 architecture using TensorRT and reduced precision, real-time analysis becomes possible without compromising accuracy. The integration of the Vanishing Point Principle for road zoning and zone-based speed calculation provides nuanced insights into driving behaviors. Detailed vehicle classification and robust tracking offer valuable data for urban planning and ecological studies. This approach increase our potential in vehicular analysis, setting new standards for research in urban development, transportation, and environmental science.

A study of the multipoint boundary value problem for nonlinear differential equations of arbitrary fractional order based on the fixed point theorem for composite nonlinear operators

Abstract The existence and distinctiveness of solutions, as well as the iterative approximations of the distinctive answer to the initial boundary value issue of nonlinear differential equations, may be solved with the help of the theory of nonlinear operators, which offers a strong theoretical guarantee and a fundamental tool. In this work, we examine the fixed point theory for composites nonlinear operators, which may offer a fresh approach to solving linear differential equations having arbitrary order fractional multipoint boundary value problems. The existing result of the boundary value issue’s solution is confirmed by the fixed point theorem for composites nonlinear operators, and the four-point boundary value problem for fractional-order linear equations of the Riemann-Liouville type is examined. A group of fractional-order nonlinear differential equations with deviating quantities are examined to examine the presence of an unusual positive solution for this boundary value problem. The existence of this unique positive solution is determined by the use of both the mixed monotone operator and the combined nonlinear operator fixed point theorem. Ultimately, the nonlinear Bagley-Torvik equation with a fractional order variable coefficient four-point boundary value problem is converted into a Fredholm-Hammerstein integral the formula of the second type with weakly singular or continuous kernels, and the fixed point principle is used to demonstrate the uniqueness of the solution in the space of continuous functions. Approximate solutions are provided for the second class of nonlinear Fredholm-Hammerstein integral equations with weakly singular kernels. The outcomes demonstrate the applicability and validity of the fixed point theorem to composite nonlinear operators, offering a fresh approach to solving the multipoint boundary value issue for nonlinear differential equations of any fractional order.

Prevalence and risk estimates of Cryptosporidium oocysts infection associated with consumption of raw-eaten vegetables in Maiduguri metropolis LGAs, Northeast Nigeria

Cryptosporidium is one of the most important protozoan parasitic pathogens, and it is a common cause of diarrhoea in humans, domestic animals, and wild vertebrates and has serious public health threats. A cross-sectional study was designed to determine the prevalence of Cryptosporidium oocysts in raw-eaten vegetables in Maiduguri Metropolitan Council (MMC) and Jere Local Government Areas (LGAs). A total of 400 samples were collected from four (4) different locations, namely Tashan Bama, Gomboru, and Monday Markets (n = 100), while fifty (n = 50) each from 202-Vegetable-Vendors and Unimaid Commercials. A total of 16 visits were conducted in all the sampling areas (twenty-five samples per visit). The Cryptosporidium oocysts were detected using the Modified Ziehl–Neelsen Staining Technique. The locations, sources, and types of raw-eaten vegetables were also assessed. The oocysts were confirmed (100×) as bright pink spherules. Data generated were analyzed using IBM-SPSS V23.0, and p ≤ 0.05 was considered significant. Out of the total samples (n = 400) analyzed, cabbage appeared to have the highest number of 10 (12.5%) of Cryptosporidium oocysts detected, while Tomato and garden egg had 9 (11.3%) and 1 (1.2%), respectively. There was a statistically significant association (χ2 = 12.5, P = 0.014) between the presence of Cryptosporidium oocysts in raw-eaten vegetables and vegetable types. Among the sources of the vegetables sampled, Alau had the highest number of Cryptosporidium oocysts, 15 (12.5%), followed by Kilari-Abdullahi and Zabarmari sources with 4 (10.0%) and 4 (5.0%), respectively. However, Jetete appeared to have the least number 2 (2.5%) of oocysts, and there was a statistically significant association (χ2= 10.4, P = 0.034) between the presence of Cryptosporidium oocysts and the sources of vegetables and fruits. The study concludes that the raw-eaten vegetables sampled from Maiduguri Metropolis were contaminated with Cryptosporidium oocysts. The study recommends that all raw-eaten vegetables should be from cleaned sources and washed before consumption. Consumers should be enlightened on the hygienic measures in the food chain in line with the Hazard Analysis and Critical Control Points (HACCP) principles.

Research on optimal scheduling method of active distribution network considering multi-type flexible resources

With the increase in the utilization rate of renewable energy, the volatility and uncertainty of active distribution networks have become more significant. Comprehensive consideration of the coordination and optimization of multiple resources can improve the flexibility of the system and promote energy consumption. Effective substitution Quantitative modeling is carried out considering a large number of flexible resources based on the flexibility of nodes and networks, combined with the physical characteristics of node flexible resources. Through the analysis of the implementation principle, control mode, and operation characteristics of the soft open point of network flexibility resource, the operation model of the soft open point with combined energy storage is established. On this basis, there are two elasticity evaluation indicators: elasticity adequacy and transmission adequacy. And we incorporate flexible benefits into optimization goals. Multiple optimization scheduling models have been created, including economy node flexibility, and network flexibility. Finally, multiple target particle swarm optimization algorithms will use the proposed scheduling model, combined with trend calculation and validation, using an improved IEEE33 node system.

Pseudo-almost periodic $C^{0}$-solution for evolution inclusion with mixed nonlocal plus local initial conditions

This paper is devoted to the study of a class of evolution inclusion in Banach spaces with nonlocal plus local mixed initial conditions. Under some mild assumptions, a unique solvability result to the multivalued evolution problem is obtained via the arguments of fixed point principle and the theory of $C^0$-semigroup.

New results for dynamical analysis of fractional-order gene regulatory networks with time delay and uncertain parameters

In this paper, a novel class of networks named fractional-order gene regulatory networks with time delay and uncertain parameters (FGRNTDUP) are formulated, and some new results are obtained for the dynamics of FGRNTDUP. Firstly, a general fractional-order differential equality is built to supply a new viewpoint about the study of finite-time stability, stabilization, and synchronization for many fractional systems. Secondly, based on contraction mapping principle, the existence and uniqueness of the equilibrium point are strictly proved for the FGRNTDUP. Meanwhile, by virtue of fractional Lyapunov method and inequality techniques, some sufficient conditions are derived to guarantee the global Mittag–Leffler stability of FGRNTDUP. Moreover, based on a newly developed inequality, some novel criteria are yielded to realize the finite-time synchronization of FGRNTDUP by designing a suitable adaptive controller. Finally, two numerical examples are provided to verify the effectiveness of the obtained results.

On Darbo’s fixed point principle

Abstract In this paper, we prove the following generalization of the classical Darbo fixed point principle : Let X be a Banach space and µ be a montone measure of noncompactness on X which satisfies the generalized Cantor intersection property. Let C be a nonempty bounded closed convex subset of X and T : C → C be a continuous mapping such that for any countable set Ω ⊂ C, we have µ(T(Ω)) ≤ kµ(Ω), where k is a constant, 0 ≤ k < 1. Then T has at least one fixed point in C. The proof is based on a combined use of topological methods and partial ordering techniques and relies on the Schauder and the Knaster-Tarski fixed point principles.