Concept Of Mechanism Research Articles

Revisiting classical concepts of Linear Elastic Fracture Mechanics - Part III: The stress field in a double-edge notched finite strip by means of the “stress-neutralization” technique

This is the third part of a short series of paper, revisiting some classical concepts of Linear Elastic Fracture Mechanics. Based on the solution for the single edge notched strip, discussed in Part-II, the present study deals with the stress field developed in a stretched finite strip, weakened by two symmetric edge notches. The notches are of parabolic shape, approximating the configuration of a rounded V-notch, varying from almost semicircular edge cavities to “mathematical” edge cracks of zero distance between their lips. The solution is obtained combining Muskhelishvili’s complex potentials technique with a procedure for “stress-neutralization” of specific areas of the loaded strip. To simplify the procedure, the notches are assumed to be “shallow” (short) so that they do not affect each other. Once the complex potentials are obtained, the stress field variations are plotted along strategic loci of the strip and along the periphery of the notches. Attention is paid to the stress field developed around the bases (tips or crowns) of the two notches, providing relatively simple formulae for the critical tensile stress. In addition, the respective stress concentration factor k is obtained for blunt notches, while in the case the edge discontinuities become “mathematical” cracks, a simple expression is given for the mode-I stress intensity factor KI at the tip of the crack. It is revealed that the assumption of “shallow” notches suffices a quite efficient solution for the overall stress field in finite strips.

Comprehensive Review of Advancements in Pharmaceutical Care and Practice

Pharmaceutical care as an ameliorative science has progressed over the past decades from the mechanical concept of medicine distribution to a more enhanced patient-centered systematic procedure incorporating outcomes of therapeutics, medication precautions, and pharmacists as a component of patient care. As such, the following extensive literature review reviews relevant literature to categorize advancements in pharmaceutical care and practice and the existing issues and advancements in the field. Specific topics include the development and future of the new individualized approach in medicine, the fate of pharmacists in condition and chronic disease management using digital health technologies, and ideas for enhancing medication therapy. This review also discusses the implications of these developments on patient outcomes, cost, and efficiency of the health system. This study underscores the importance of leadership by pharmacists and advocacy for equal access of patients to drugs irrespective of their social status, compliance with recommended schedules, and other ways of increasing the effectiveness of the medication. Consequently, the review concludes by advancing recommendations aimed at improving the future of pharmaceutical care by conducting future research, adopting better policies, and providing better training to the practitioners.

Current Concepts in the Molecular Mechanisms and Management of Diabetic Neuropathy by Pharmacotherapeutics and Natural Compounds.

One of the most crippling effects of diabetes mellitus is diabetic neuropathy, which can cause discomfort, loss of movement, and even amputation. Diabetic neuropathy manifests in a variety of ways, ranging from pain to death. Diagnosing diabetic neuropathy can be challenging since it often goes unnoticed for many years following the onset of diabetes. In addition to oxidative stress in neurons, hyperglycemia activates a number of metabolic pathways that are important sources of damage and possible targets for treatment in diabetic neuropathy. Downstream metabolic cascades caused by prolonged hyperglycemia include activation of protein kinase C, increased production of advanced glycation end products, excessive release of cytokines, increased oxidative stress, and injury to peripheral nerves. Despite the fact that these metabolic anomalies are considered the main cause of diabetes-related microvascular issues, the diverse mechanistic processes of neuropathy are characterized by organ-specific histological and biochemical features. Although the symptoms of diabetic neuropathy can be treated, there are few options to correct the underlying problem. Diabetic neuropathy exerts a tremendous financial, psychological, and physical burden on society, emphasizing the need for efficient and focused treatment. The major goal of this review is to shed light on the multiple mechanisms and pathways that contribute to the onset of diabetic neuropathy and to provide readers with a comprehensive understanding of emerging therapeutic strategies to postpone or reverse various forms of diabetic neuropathy. The article discusses available medications and provides the latest guidelines for the treatment of pain and distal symmetric polyneuropathy, including diabetic autonomic neuropathy, which may help the patients control pain well and assess alternatives for treatment that might be more successful in preventing or delaying the course of a disease.

A brief review on declarative concepts of pharmaceutical characteristics, classification, mechanisms, preparation, formulation and evaluation studies of moisturizing cream

The pharmaceutical creams play important role on tropical applications in which moisturizers are one of the widely industrial preparations involved for to nourish, soften and moisten the skin for the clients. These are mainly effectively works on dry skin clients combating various cases such as itch, pain, stinging, tightness, tingling and many more problems. The moisturizers are products mainly aimed to raising the SC’s water surface content helps the skin smooth, hydrates and hence maintaining a normal pH of skin. They are classified as emollients, humectants, occlusives and protein rejuvenators moisturizers helps to aid skin layers and even modifies its barriers. But its ingredients needed to be considered as non-irritant, nontoxic and non-adverse effects. This review main purpose is to describe about the overall published studies being for making moisturizing creams are interest able, advantageous and all the characteristics, mechanism, preparation, formulation and evaluation within the elegant criteria fulfilled. Even have clinical details for various disorder which are already been suggested by expert as well as adjuvant therapy suggested by experts. The patterns are being studied about water-in-oil emulsion design along with its needs which are being qualified under evaluation parameters for to know about qualified moisturizing creams.

Some aspects of ensuring the rights of persons with disabilities in the activities of the Council of Europe

The article is devoted to the study and analysis of the acts defining the rights of persons with disabilities, providing for the ways of their guarantee and protection, which were adopted within the Council of Europe. The concept of human rights mechanisms, in particular, in the activities of regional international intergovernmental organisations, is revealed. The author demonstrates the complex multilevel nature of the European system of human rights protection, which includes special regulatory and institutional instruments. Some acts of the so-called ‘soft law’ of the Council of Europe are analysed. It is shown that the first documents of the Council of Europe in the field of the rights of persons with disabilities concerned mainly the economic rights of this category of persons. Particular emphasis was placed on the importance of ensuring the required number of jobs, professional retraining and professional assessment of employees who have lost the ability to perform certain types of work. With the further improvement of human rights protection mechanisms, the Council of Europe’s strategy for ensuring the rights of persons with disabilities has also changed. Member states agreed on the importance of expanding the range of freedoms for people with disabilities. This was due to the existence of numerous barriers to access to social services, cultural life of society, diversification of leisure activities, etc. The recommendations that were subsequently adopted included provisions on the absolute prohibition of discrimination on the basis of disability in such areas as education, transport, public services, political, social and cultural life of the state. The article also analyses the concept of universal design, which was introduced to ensure that the infrastructure of European countries is accessible so that every person with a disability can receive the necessary social services with minimal interference from third parties. The article examines the issue of protection of persons with disabilities from violence and ill-treatment, whether committed by relatives, healthcare professionals or third parties. The author identifies the categories of persons who are more vulnerable due to the combination of disability with certain other characteristics, such as age, gender, social status, citizenship, etc. The author reveals a new approach of the Council of Europe to ensuring the rights of persons with disabilities, which provides for the elimination of social barriers and their full integration into society.

Studies of SiC‐Filled Al6061 Metal Matrix Composite Optical, Mechanical, Tribological, and Corrosion Behavior with Strengthening Mechanisms

The objective of the current study is to produce metal matrix composites (MMCs) using ultrasonic‐assisted stir casting and Al6061 alloy reinforced with silicon carbide (SiC) microparticle reinforcement in weight percentages of 0, 2, 4, and 6. The microstructural alterations of Al6061–SiC composites are investigated using a scanning electron microscope (SEM) equipped with an energy‐dispersive X‐ray (EDAX). By adding more nucleation sites for the formation of smaller grains, SiC reinforcement of the Al6061 matrix encourages grain refining. The SiC addition significantly changes the microstructure of Al6061 composites, enhancing their mechanical qualities. In addition to increasing density by 0.6%, hardness by 33%, and tensile strength by 33%. The increased SiC content dramatically decreases elongation by 42%. The strength of Al6061–SiC MMCs is predicted using several strengthening mechanism concepts as part of the continuing investigation. For Al6061–SiC composites, the strengthening contribution from thermal mismatch is more significant than that from Orowan strengthening, Hall–Petch mechanism, and load transmitting effect. Grain refinement interactions, load transmission mechanisms, and the strengthening effects of CTE differences and dislocations between matrix and reinforcement particles are studied. The composite with 6‐weight percent SiC reinforcement performs better in dry sliding wear and corrosion resistance.

Abstract 4137249: Left atrial functional reserve predicts recurrence of atrial arrhythmia following catheter ablation in patients with persistent atrial fibrillation

Background: Left atrial (LA) functional remodeling plays an essential role in the pathophysiological mechanisms of atrial fibrillation (AF). LA reservoir strain (LARS) measured by speckle-tracking echocardiography (STE) exhibits acceptable predictive value for recurrent atrial arrhythmia in patients with paroxysmal AF, while its performance in persistent AF remains inconclusive. Recently, LA functional reserve, a novel concept of LA mechanics in response to acute-volume overload, is drawing attention. Research Questions: Are LARS and LA functional reserve associated with recurrent atrial arrhythmia after catheter ablation in patients with persistent AF? Methods: Ninety-two patients who underwent first catheter ablation for persistent AF were included in the study. LARS at rest and LA functional reserve were assessed by STE 1-4 days before catheter ablation. LA functional reserve was calculated as change in LARS after passive leg lifting. Recurrence of arrhythmia was defined as atrial arrhythmia of ≥ 30 seconds duration after a 2-month blanking period. Results: The median values of LARS and LA functional reserve were 14.4 % (interquartile range [IQR] 10.9 to 18.2) and 1.0% (IQR -1.2 to 3.6), respectively. During a mean follow-up of 13.2 ± 9.9 months, 29 (31.5%) patients experienced recurrent AF. When we stratified patients into 2 groups according to LARS and LA functional reserve (below vs. above median values), patients with impaired LA functional reserve (< 1.0%) were at higher risk of AF recurrence (log-rank test p value=0.026), but this was not observed for LARS (Figure). In multivariable Cox proportional hazard analysis, impaired LA functional reserve was associated with recurrent atrial arrhythmia independent of AF risk factors, left ventricular ejection fraction and LARS at rest (adjusted hazard ratio 3.99, p=0.004). Conclusions: Evaluation of LA functional reserve may provide valuable information for optimal patient selection as well as follow-up strategy after catheter ablation in patients with persistent AF.

Statutory Concepts of the Mechanism of Regulating Property Turnover Relations

Introduction: the scientific paper aims to analyze the conditions for the formation of the statutory concept of the mechanism of the civil regulation of property (civil) turnover relations. The relevance of the topic is related to the specifics of property turnover relations, which determines the individual (for specific participants in legal relations) statutory concept of regulating and the need to determine the conditions for the formation of the statutory concept for regulating relations within the framework of property turnover. Methods: as a part of the study, a comparative law method was used, which made it possible to identify differences in violations when using the image of a citizen; a systematic approach; a formal logical research method. Results: the analysis of the current legislation of the Russian Federation has been carried out, and the conditions associated with the formation of the statutory concept of the mechanism of the civil regulation of relations in the field of property turnover have been determined. Conclusions: it is determined that the basic statutory concept of the civil mechanism is formed taking into account the objectives of the activities of the participants in the turnover and can be supplemented depending on the circumstances. Such a statutory concept legally ensures the satisfaction of private interests. In case of violation of interests, the protective means of the mechanism of the civil regulation are used, which “help” to restore the property status of the injured party.

Use of PhET to enhance the learning of mechanical energy in high school students of the Fiscomisional Educational Unit “Cinco de Mayo”

The use of the PhET simulation has proven to be an effective tool to improve the learning of mechanical energy in third-year high school students of the Fiscomisional Educational Unit "Cinco de Mayo". This research aimed to apply said simulator to facilitate the understanding of key concepts such as energy conservation, types of energy and energy transformation. Theoretical methods were used to collect information and empirical methods to evaluate its effectiveness, such as survey, interview and observation sheet. The results obtained showed that the use of the PhET simulation promoted a better understanding of mechanical energy concepts, allowing students to interactively visualize complex phenomena that would otherwise be difficult to illustrate with traditional methods. Furthermore, it was found that this digital tool made the teaching-learning process more attractive and dynamic, significantly improving the participation and motivation of students in the classroom.

Examining mechanics problem-solving strategies among engineering students at a selected public university in Rwanda

Abstract This paper presents the findings of research conducted at a selected university in Rwanda aiming to evaluate the mechanics of problem-solving strategies among engineering students. Problem-solving is an important component of science, technology, engineering, and mathematics education as well as in everyday life. To enhance the development of problem-solving skills, researchers and curriculum creators must develop problem-solving strategies for solving mechanics problems and for improving engineering students’ performance in physics classroom tasks. The study investigated engineering students’ strategies for their mechanics problem-solving using a mixed-methods research approach that includes questionnaires, interviews, and tests. A purposive sample of 99 students was chosen, with 20 students and three instructors randomly selected for interviews. Findings revealed that students heavily rely on algebraic equations, neglecting visual representations in mechanics problem-solving. Challenges identified include limited familiarity with alternative representations, difficulties transitioning between them, and a constrained understanding of their interrelationships. Recognizing these practices and strategies informs the design of more effective pedagogical interventions. Incorporating the best problem-solving strategies in physics education is a potential avenue to bolster problem-solving skills and deepen comprehension of mechanics concepts among engineering students.

On cat–human interaction from the viewpoint of physics: An equation of motion

This paper provides an enjoyable example through which several concepts of classical mechanics can be understood. We introduce an equation that models the motion of a cat in the presence of a person. The cat is considered as a point particle moving in a potential induced by the person. We demonstrate that this approach to the problem reproduces characteristic behaviors of these curious animals. For instance, the fact that cats do not typically come when they are called, or that they remain longer on the lap of their favorite person; even “zoomies” are reproduced (cats randomly run back and forth across the house). We use this model problem to explore topics of current research such as stochastic equations and periodically driven systems. The pedagogical value of this work and its potential use in teaching are discussed.

Geospatial assessment and integrated multi-model approach for landslide susceptibility mapping in Meghalaya, India

Landslides in Meghalaya, India, inflict severe property and life damage due to mountains, steep slopes, and heavy rains. Landslide Susceptibility (LS) maps are extremely useful for disaster management. The primary goal of this work is to generate an LS map for the state of Meghalaya. In the first phase, a Landslide Inventory (LI) map was created, which included 855 landslides that occurred from 2019 to 2023. The LI map was then split into 70 % (601) and 30 % (254) for training and testing, respectively. In the second phase, the study selected fourteen conditioning factors as thematic layers for LS mapping and performed multicollinearity and Pearson’s correlation analysis; all the parameters were identified as optimal for the prediction model. Eight different scenario models (Frequency Ratio (FR), Evidence Belief Function (EBF), FR + EBF, FR*EBF, (FR*EBF)/2, (2*FR) + EBF, (2*EBF) + FR and (EBF + FR)/3) have been used to generate LS maps. The created maps were validated using Receiver Operating Characteristics (ROC) curve and the corresponding Area Under the Curve (AUC) value, statistical measures (recall, precision, F1 score, overall accuracy, and balanced accuracy) and on-site verification with recent landslides. Finally, the result of the best scenario was compared with the outcome of the Analytical Hierarchy Process (AHP) method. Results showed that scenario 4 (EBF*FR) has an overall accuracy of 82.3 %, whereas AHP has an overall accuracy of 77.6 %. It is indicated that scenario 4 achieved 4.7 % higher overall accuracy than that of the AHP method. Recent landslides selected for on-site verification occurred in an area classified as very highly susceptible by the scenario 4 model. These maps provide vital conceptions of landslide mechanisms, assisting land use planning and disaster management. This approach can be applied in similar areas by investigators, which indicates the originality of the study, and the result of this study will be beneficial for the Meghalaya region.

An updated quantum complementarity principle

Bohr’s complementarity principle has long been a fundamental concept in quantum mechanics, positing that, within a given experimental set-up, a quantum system (or quanton) can exhibit either its wave-like character, denoted as W , or its particle-like character, denoted as P , but not both simultaneously. Modern interpretations of Bohr’s complementarity principle acknowledge the coexistence of these aspects in the same experiment while introducing the constraint W + P ≤ α . Notably, estimations of W or P frequently rely on indirect retrodiction methods, a practice that has led to the claim of the violation of Bohr’s complementarity principle. By taking a different route, recent advancements demonstrate that quantum complementarity relations can be rigorously derived from the axioms of quantum mechanics. To reconcile these observations and eliminate potential paradoxes or violations, we propose an updated formulation for the quantum complementarity principle, which is stated as follows: For a given quantum state preparation ρ t at a specific instant of time t , the wave and particle behaviours of a quanton are constrained by a complementarity relation 𝔚 ( ρ t ) + 𝔓 ( ρ t ) ≤ α ( d ) , which is derived directly from the axioms of quantum mechanics.

The limits of mathematics in physics

Mathematics is considered the language of physics. Starting from idealizations and kinematics, geometric-mathematical physics with paradigms such as flexible spacetime and dark energy has emerged whose physical reality has not been clarified. By analyzing processes regarding their causes and the functional dependencies of energies, this work identifies shortcomings in the basic energy concepts of physics, which cannot be remedied with mathematics. While formal transformations of process equations such as integration are mathematically correct, they do conceal vital physical information, suggesting that mathematics should be used with caution. We propose a physically justified approach that reconciles the mechanical and thermodynamic energy concepts and provides a revised interpretation of E = mc2. Our results suggest that geometric approaches were built too early on a shaky physical foundation, leading to undesirable developments in recent centuries. The language of physics should be physics, not just mathematics.

The Crack Growth Resistance of Polymeric Cellular Materials Studied With a Quasi‐Brittle Approach

ABSTRACTThis research delves into the fracture analysis of cellular thermosetting polymers using Mode I fracture tests with a compact tension geometry subjected to both monotonic and cyclic loadings. The equivalent linear elastic fracture mechanics concept effectively described crack initiation and propagation. Numerical simulations estimated the equivalent linear elastic crack length aligning with experimental measurements. Resistance curves revealed a transient regime followed by a self‐similar regime with relatively constant fracture energy, typical of quasi‐brittle materials. Finally, the fracture energy evolution correlated with macroscopic density evolution exhibiting a linear relationship relaying the influence of microstructure to a second order.

Corporate Governance: Exploring Key Concepts, Mechanisms, and Historical Evolution

Corporate governance involves several key concepts that help define its scope and purpose. Though review of key corporate governance concepts and historical evolution is widespread in the extant literature, detailed review across the globe is limited. Motivated by this dearth, this study reviewed these concepts and explored how firms rely on them to implement effective corporate governance. The study employed documentary and descriptive research methods to review concepts of corporate governance, systems, mechanisms and historical perspectives around the world. Our study discovered that understanding internal controls helps ensure compliance, minimize risks and safeguard the firm’s assets. Similarly, the study discovered that executive compensation structures help align management interests with shareholder value and external oversight through auditing and regulation which provides an unbiased assessment of the firm’s financial reports. Our historical perspective of corporate governance highlighted significant milestones that have shaped its evolution. Importantly, these include reports and acts aimed at addressing corporate scandals and improving governance practices. We also discovered that to improve corporate governance standards worldwide, multilateral organizations like the Organisation for Economic Cooperation and Development (OECD) among others have played a number of roles in developing international guidelines and codes of best practice. Further, the study explored the dynamic nature of corporate governance in response to evolving economic, social and technological trends. The study concluded that understanding the concepts, systems, mechanisms and historical perspectives of corporate governance is essential for firms and stakeholders to maintain transparency, accountability and sustainable performance.

Contextual success and pitfalls of mHealth service for maternal and child health in Africa: An Intervention, Context, Actors, Mechanism, and Outcome (ICAMO) framework guided systematic review of qualitative evidence

IntroductionMobile health (mHealth) interventions have shown potential to improve maternal and child health outcomes in Africa, but their effectiveness depends on specific interventions, context, and implementation quality. Challenges such as limited infrastructure, low digital literacy, and sustainability need to be addressed. Further evaluation studies are essential to summarize the impact of mHealth interventions. Thus, this synthesis focuses on qualitative evidence of the impact of mHealth on maternal and child health in Africa to summarize such evidence to help policy decisions.MethodsA qualitative systematic review guided by the concepts of Intervention, Context, Mechanism, and Outcome (ICAMO) was employed in this study. The GRADE CERQual assessment and methodological constraints tools were utilized in the review to ascertain the level of confidence in the evidence and to examine the methodological limitations. The JBI checklist for qualitative research appraisal was also consulted during the review.ResultsThe current review contains 32 eligible studies from databases such as CINAHL, EMBASE, MEDLINE, Scopus, Web of Science, HINARI, and Cochrane Library. The review demonstrated substantial improvements in the HCP-woman relationship, communication system, maternal and child healthcare uptake, health-seeking behavior, and HCP skills. Economic capacities, maternal education, and the low quality of existing services challenged participants.ConclusionmHealth significantly improves maternal and child health outcomes in Africa. This review showed it can improve healthcare access, empower women, and contribute to the region's goal of universal health coverage. However, the challenges such as low partner support, high costs for services, and poor quality of current care as narrated by women need commitment from health authorities in the continent. The evidence from this review suggests that mHealth can be implemented to improve maternal and child health in Africa.Trial registrationPROSPERO: CRD42023461425.

Peripheral blood to next-generation sequencing ready DNA library: a novel engineering design for automation

Whole genome sequencing (WGS) has become a gold standard for diagnosing genomic variation. Peripheral blood is a common sample source for the extraction of nucleic acids for Next-Generation Sequencing (NGS) applications. Here, we present an integrated and fully automated device design that uses new concepts of fluid mechanics, heat-mass transfer, and thermodynamics of enzymatic reactions to extract nucleic acids from the blood and perform DNA library preparation from a pre-filled plate. We demonstrate that the presented device effectively extracts dsDNA with an average of 25.03 µg/mL and 25.91 µg/mL yield from citrate-stabilized human peripheral blood stored in Fresh (4 °C) and Frozen (-20 °C) conditions, respectively. Furthermore, our method automatically extracts nucleic acids and creates a high-quality sequence-ready DNA library from blood stabilized with citrate and EDTA for 8 samples simultaneously in a single run with a total operation time of ~ 7 h. Our results show the required coverage and depth of the genome, highlighting an essential application of this device in processing blood samples for genome sequencing.Graphical

Symmetry Preservation in Hamiltonian Systems: Simulation and Learning

This work presents a general geometric framework for simulating and learning the dynamics of Hamiltonian systems that are invariant under a Lie group of transformations. This means that a group of symmetries is known to act on the system respecting its dynamics and, as a consequence, Noether’s theorem, conserved quantities are observed. We propose to simulate and learn the mappings of interest through the construction of G-invariant Lagrangian submanifolds, which are pivotal objects in symplectic geometry. A notable property of our constructions is that the simulated/learned dynamics also preserves the same conserved quantities as the original system, resulting in a more faithful surrogate of the original dynamics than non-symmetry aware methods, and in a more accurate predictor of non-observed trajectories. Furthermore, our setting is able to simulate/learn not only Hamiltonian flows, but any Lie group-equivariant symplectic transformation. Our designs leverage pivotal techniques and concepts in symplectic geometry and geometric mechanics: reduction theory, Noether’s theorem, Lagrangian submanifolds, momentum mappings, and coisotropic reduction among others. We also present methods to learn Poisson transformations while preserving the underlying geometry and how to endow non-geometric integrators with geometric properties. Thus, this work presents a novel attempt to harness the power of symplectic and Poisson geometry toward simulating and learning problems.

On the relation between entropy and crack driving force

The concept of debonding entropy provides insight into the physical mechanisms of fracture. It sheds light on how the fracture phenomenon is more intimately related to degradation and entropy. This paper aims to investigate the relationships between debonding entropy and fundamental concepts in fracture mechanics. A direct, simple relationship between debonding entropy and the J-integral value at fracture is developed and validated. The validation of this relation displays the connection between fracture mechanics and entropic degradation.