Functional integration Research Papers - Academia.edu (original) (raw)

2025, Tijdschrift voor economische en sociale geografie

German seaports are in a phase of far-reaching structural change. Increasing globalisation of the economy has led to gowing international trade volume and a corresponding increase in transport streams. Economic changes are particularly marked in the Baltic region which affects, above all, the German Baltic seaports. The two large container ports of Hamburg and Bremen/Bremerhaven are primarily faced with economic and technical-organkational changes in intercontinental container transport. Restructuring of the ports is currently governed by an adjustment of port infrastructures to the changed requirements of transport and services, and an extension of hinterland relations. Changes in the institutional and Financial structures of German ports are likely in view of the chronic crisis situations of public budgets and the attempts of the European Commission to apply the principle of spreading costs fairly to all European ports, on the basis of standardised cost recording and accounting. The introduction of containers resulted in spiralling labour productivity, with a consequent loss in jobs in the operative core area of the port economy. In view of this forced logistic structural change ports become 'container floodgates', a 'logistic channel' through which cargo passes. Most port regions are attempting to counteract the job decline in the operative function sector carried out by the seaport through developing the services offered towards "value-added logistics". The functional changes of ports modify economic linkages of ports and regions. The immediate linkages of ports and sea-oriented industries are decreasing and differentiated economic and social networks are emerging in the shape of transport and logistic service centres, although their interlinked relations are no longer one-sidedly port-based.

2025, Nuclear Physics B

We explore the formulation of non-rational 2D quantum gravity in terms of a chiral CFT on a Riemann surface associated with the target space. The CFT in question is constructed as the collective theory for a matrix chain, which is dual to a statistical height model on dynamical triangulations. The heights are associated with the sheets of the Riemann surface, which represents an infinite branched cover of the spectral plane. We consider two examples of height models: the SOS model and the semi-restricted SOS (SRSOS) model, in which the heights are restricted from below. Both models are described in the continuum limit by theories of 2D quantum gravity with conformal matter, perturbed by a thermal operator (1,3). We give a compact operator expression for the n-loop amplitudes as a collection of target space Feynman rules. The n-point functions of local fields are obtained by shrinking the loops. In particular, we show that the 4-point function of order operators in the SRSOS model coincides with the 4-point function of the "diagonal" world sheet CFT studied in .

2025, Physics Letters B

We find the precise relationship between the loop gas method and the matrix quantum mechanics approach to two-dimensional string theory. The two systems are distinguished by different target spaces (Z Z and IR, respectively) as far as observables are concerned. We argue that target space loop correlators should coincide in the two models and demonstrate this for a number of examples. As a consequence some interesting generic observations about the structure of two-dimensional string theory may be made: Restricting to a discrete target space leads to factorization of amplitudes and thus to very simple sewing rules. It is also demonstrated that the restriction to the discrete target space still allows to calculate the correlation functions of tachyon operators in the unrestricted theory.

2025

We present a unified theoretical framework for neural system modeling that addresses the fundamental challenge of coherent abstraction across biological and artificial systems. Building on experimental insights from gamma synchronization, attention mechanisms, and neural dynamics, we propose a multi-scale approach that dynamically adapts model complexity while maintaining functional integrity. Our framework resolves long-standing issues in neural modeling regarding appropriate levels of detail and bridges biological and artificial neural systems through principled abstraction.

2025, Neuropeptides

The aim of the present work was to investigate the role of brain l, j and d opioid receptors in the central serotonergic mechanisms regulating blood pressure in rats. The data obtained show that: (1) pharmacological activation of central 5-HT 3 receptors yields a significant decrease in blood pressure; (2) the blockade of those receptors by a selective antagonist induces an acute hypertensive response; (3) the pharmacological blockade of central opioid receptors by three different opioid antagonists exhibiting variable degrees of selectivity to l, j and d opioid receptors always suppressed the hypotensive response induced by central 5-HT 3 receptor stimulation; (4) the blockade of opioid receptors by the same opioid antagonists that impaired the hypotensive effect of central 5-HT 3 receptor stimulation failed to modify blood pressure in animals not submitted to pharmacological manipulations of central 5-HT 3 receptor function. It is shown that a 5-HT 3 receptor-dependent mechanism seems to be part of the brain serotonergic system that contributes to cardiovascular regulation since the hypertensive response observed after ondansetron administration indicates that central 5-HT 3 receptors exert a tonic inhibitory drive on blood pressure. Furthermore, the data obtained here clearly indicate that the hypotensive response observed after pharmacological stimulation of central 5-HT 3 receptors depends on the functional integrity of brain l, j and d opioid receptors, suggesting that a functional interaction between serotonergic and opiatergic pathways in the brain is part of the complex, multifactorial system that regulates blood pressure in the central nervous system.

2025

It is well-known that gauge fields defined on manifolds with spatial boundaries support states localized at the boundary. In this talk, we show how similar states arise in canonical gravity abd discuss their physical relevance using their... more

2025, Theoretical and Mathematical Physics

We discuss the relation between the functional integral over open Riemann surfaces and the operator formalism on closed Riemann surfaces. The states in the latter formalism arise in the holomorphic representation of the functional integral.

2025

These lecture notes cover my talks at the June 2009 "Geometry of Quantum Fields and Strings" summer school at the University of Pennsylvania. I begin by giving a very brief introduction to quantum field theory, quickly moving to nonlinear sigma models and the associated A and B model topological field theories, and the physical realization of derived categories. Later lectures will cover Landau-Ginzburg models, matrix factorization, gauged linear sigma models, and mirror symmetry.

2025, arXiv (Cornell University)

In this effort, we define a new class of fractional analytic functions containing functional parameters in the open unit disk. By employing this class, we introduce two types of fractional operators, differential and integral. The fractional differential operator is considered to be in the sense of Ruscheweyh differential operator, while the fractional integral operator is in the sense of Noor integral. The boundedness and compactness in a complex Banach space are discussed. Other studies are illustrated in the sequel.

2025, Science

tyrosine kinase, then IFN--y and GM-CSF would have different pathways of action. The regulation of macrophage activation by GM-CSF provides a mechanism whereby T lymphocytes, in response to antigen, may regulate a nonspecific effector function of macrophages in the absence of any requirement for an exogenous signal provided by bacterial products. This may therefore repre- sent an important pathway of antitumor defense.

2025, Gut

Antipyrine elimination was studied in 29 patients with obstructive jaundice. Antipyrine half-lives calculated using plasma concentrations at four and 24 hours ('short antipyrine test') were significantly correlated with those calculated using six time points (p<0.001). Mean antipyrine half-life was 28.3±8 hours (standard error) and was significantly longer than in normal subjects (p<0.001). Antipyrine half-life did not correlate with standard biochemical liver function tests, but correlated positively with the postoperative half-time for clearance of endogenous bilirubin (p<005), and negatively with hepatic cytochrome P-450 content measured in peroperative liver biopsies (p<0-05). Of six patients with antipyrine half-life >20 hours, four died, one preoperatively of gastrointestinal haemorrhage and three postoperatively of sepsis. Serial short antipyrine tests were performed in 13 patients before and after biliary drainage. Those with an initial antipyrine half-life greater than 15 hours showed significant changes after drainage, while those with an antipyrine half-life less than 15 hours did not. The test of antipyrine half-life may aid in selecting high risk patients with obstructive jaundice for percutaneous biliary drainage before definitive surgery, and in determining the optimal time for such preliminary biliary decompression. Surgery for obstructive jaundice carries a high mortality rate," which may be as great as 25-30% in

2025, Production Journal

O Processo de Desenvolvimento de Produtos (PDP) pode ser definido como a maneira pela qual uma empresa converte ideias e oportunidades em produtos e serviços. Esse processo exige etapas bem definidas e administração de pessoas e recursos. Nos últimos anos, surgiram modelos referenciais de desenvolvimento que se aperfeiçoaram e incorporaram novas fases no desenvolvimento de produtos, desde a análise do mercado até a descontinuidade do produto. Apesar disso, no que se refere à estruturação do PDP, de um modo geral, as empresas, sobretudo pequenas e médias, não adaptaram facilmente à sua realidade os modelos defendidos nos livros. Claramente, falta uma função de transição entre a prática atual e as propostas teóricas. Baseado na literatura e na prática observada em empresas, este artigo apresenta um método de estruturação das atividades concernentes ao PDP de empresas de bens de manufatura. A proposta contempla a apresentação de um método utilizado para melhoria da integração das atividades. Os métodos utilizados mostram como, na prática, pode ser feita a intervenção em uma empresa de médio porte que deseja organizar seu Processo de Desenvolvimento de Produtos.

2025, DS 60: Proceedings of DESIGN 2010, the 11th International Design Conference, Dubrovnik, Croatia

2025

The effective spin Hamiltonian is constructed in the framework of the almost half-filled Hubbard model on the Cayley tree by means of functional integral technique with the use of static approximation. The system in the ground state appears to be consisting of the ferromagnetic metallic domains and the antiferromagnetic insulating one sprovided that the concentration of excess electrons (or holes) does not exceed some critical value. The connection between the Hubbard model and the s-f model is stated.

2025, preprint

This article challenges the classical ideal of scientific unity as theoretical or ontological reduction. Against the backdrop of contemporary science's increasing fragmentation, it proposes an alternative model of unity grounded in the structural coordination of constraint regimes. Drawing on recent work in structural realism, epistemology of practice, and anti-reductionist philosophy of science, it argues that the coherence of science emerges from functional compatibility between localized, heterogeneous models, not from global integration under a common theory. The resulting account reframes unity as a systemic property of interaction across epistemic regimes.

2025, PROCEEDINGS-SPIE …

The next generation microprocessor assemblies will require integrated thermal management design solutions as the device density and clock speeds increase. These solutions will include a heat spreader, or lid, that is in contact with the heat generating microprocessor in the total packaging assembly. The materials choice for these integrated heat spreader solutions must provide the following material property attributes. • High bulk thermal conductivity • CTE compatibility with the Device and/or Microprocessor Assembly • EMI/RFI Shielding • Light weight • Dimensional Stability/Flatness (minimize bond line length resulting in a decreased Θ JC ). • Competitive Pricing AlSiC, Aluminum Silicon Carbide, metal matrix composite materials meet the material property, design and pricing demands for microprocessor assemblies that require integrated heat sink thermal management solutions. The CTE of AlSiC material and components can be tuned to be compatible with the specific heatsink application by controlling the SiC volume fraction in the AlSiC composite. AlSiC products with CTE values 7 -9 ppm/°C (30 -250°C) are suitable for direct attachment to GaAs and Si devices and ceramic substrate. Higher CTE materials 10 -12 ppm/°C are used for attachment to printed circuit boards. The AlSiC thermal conductivity value is 180 -200 W/mK (compositional dependent) similar to CuMo and CuW materials. The material density of AlSiC is 1/3 rd to 1/5 th that of CuMo and CuW making AlSiC more suited to weight sensitive applications. The Ceramics Process Systems AlSiC components are cost-effectively fabricated to net-shape attaining close dimensional tolerances with minimal machining. The AlSiC material composition (hence CTE) is controlled by monitoring the SiC volume fraction of a tightly toleranced SiC preform fabricated with the QuickSet™ injection molding process. The pore structure of the SiC preform is infiltrated with molten Almetal (termed the QuickCast™ process) to form the AlSiC composite material to the exact product dimensions defined by the infiltration mold. The combined processes form a fully dense, hermetic material of discrete SiC particulate in a continuous Al-metal matrix phase. This process is currently used for high volume production for a number of product geometries and thermal management applications including MPU integrated heat spreading lid solutions. The ideal material properties coupled with AlSiC fabrication process provide low-cost highperformance functional integrated thermal management heat spreading solutions for microprocessor applications. This paper will illustrate the AlSiC material/design capabilities through microprocessor heat spreader examples.

2025, Journal of Cognitive Neuroscience

Positron emission tomography (PET) and functional magnetic resonance imaging (fMRI) have been extensively used to explore the functional neuroanatomy of cognitive functions. Here we review 275 PET and fMRI studies of attention (sustained, selective, Stroop, orientation, divided), perception (object, face, space/motion, smell), imagery (object, space/ motion), language (written/spoken word recognition, spoken/ no spoken response), working memory (verbal/numeric, object, spatial, problem solving), semantic memory retrieval (categorization, generation), episodic memory encoding (verbal, object, spatial), episodic memory retrieval (verbal, nonverbal, success, effort, mode, context), priming (perceptual, conceptual), and procedural memory (conditioning, motor, and nonmotor skill learning). To identify consistent activation patterns associated with these cognitive operations, data from 412 contrasts were summarized at the level of cortical Brodmann's areas, insula, thalamus, medial-te...

2025, Polifunctions: A Formal Framework for Multi-Valued Mathematical Functions

This paper introduces a novel formal framework for functions that can simultaneously return multiple values, sets, intervals, or other complex mathematical structures for a single input. We define the concept of a "polifunction" as a generalization of traditional functions, multi-valued functions, and relations. This framework bridges the gap between mathematical theory and practical applications in computer science and physics, where returning multiple values is often natural or necessary. We develop a comprehensive algebra for operations on polifunctions and explore their properties. The proposed framework has potential applications in various fields, including quantum mechanics, complex analysis, and computational mathematics, where traditional single-valued functions may be insufficient to model intrinsic multiplicity or simultaneous outcomes.

2025

Classification of structural properties of human bones is essential for understanding differential response to loading and fracture risk. Ribs, in particular, are frequently fractured during motor vehicle crashes and are linked to high mortality rates, especially in elderly individuals. While many studies describe variation of bone properties with respect to age and sex differences, these parameters explain only a small amount of variability in rib properties. Geometric properties can also have a significant effect on how a bone will respond to loading. The goal of this study is to investigate the ability of gross and cross-sectional geometric properties of human ribs to predict experimental structural properties.

2025, How does the brain work

Introduction: The Mystery of Neural Cooperation How does the brain and the many billions of neurons know how to work together? Who creates the rules for this highly complex network? In a human brain, about 86 billion nerve cells interact with each other via trillions of connections-and yet this enormous network does not give rise to chaotic activity, but to precise perception, thinking and consciousness. This question of the "how" of brain function is one of the greatest challenges of modern science. Unlike a computer, there is no central control unit in the brain, no "programmer" who sets the rules. Nevertheless, neurons work in a coordinated interaction that enables us to perceive, think and act on the world. Conventional explanations often look at the brain either from a purely physical perspective (as a complex network of electrical signals) or from a psychological perspective (as a site of mental processes). However, neither approach manages to completely bridge the gap between the physical structure of the brain and its mental functions. In this article, we present an approach based on the concept of "polyvalence coupling"-a principle that could help to look at the mystery of brain function from a completely new perspective.

2025, Journal of Physics A: Mathematical and General

We study the quantization problem of relativistic scalar and spinning particles interacting with a radiation electromagnetic field by using the path integral and the external source method. The spin degrees of freedom are described in terms of Grassmann variables and the Feynman kernel is obtained through functional integration on both Bose and Fermi variables. We provide rigourous proof that the Feynman amplitudes are only determined by the classical contribution and we explicitly evaluate the propagators.

2025, Physical Review D

A free nonrelativistic particle moving in a one-dimensional box can be described by any of a four-parameter family of self-adjoint Hamiltonians each of which guarantees that probability does not leave the box. Included are cases where the particle striking one wall may reappear at the other. We construct a four-parameter family of Brownian functional integrals which include paths that jump from wall to wall. Their analytic continuation in time results in the same quantum Green's functions as those which arise directly from the Hamiltonians.

2025, Journal of Mathematical Physics

A free nonrelativistic particle moving in two dimensions on a half-plane can be described by self-adjoint Hamiltonians characterized by boundary conditions imposed on the systems. The most general boundary condition is parameterized in terms of the elements of an infinite-dimensional matrix. We construct the Brownian functional integral for each of these self-adjoint Hamiltonians. Nonlocal boundary conditions are implemented by allowing the paths striking the boundary to jump to other locations on the boundary. Analytic continuation in time results in the Green’s functions of the Schrödinger equation satisfying the boundary condition characterizing the self-adjoint Hamiltonian.

2025

We consider a framework in which low energy dynamics of quantum gravity is described preserving locality, and yet taking into account the effects that are not captured by the naive global spacetime picture, e.g. those associated with black hole complementarity. Our framework employs a "special relativistic" description of gravity; specifically, gravity is treated as a force measured by the observer tied to the coordinate system associated with a freely falling local Lorentz frame. We identify, in simple cases, regions of spacetime in which low energy local descriptions are applicable as viewed from the freely falling frame; in particular, we identify a surface called the gravitational observer horizon on which the local proper acceleration measured in the observer's coordinates becomes the cutoff (string) scale. This allows for separating between the "low-energy" local physics and "trans-Planckian" intrinsically quantum gravitational (stringy) physics, and allows for developing physical pictures of the origins of various effects. We explore the structure of the Hilbert space in which the proposed scheme is realized in a simple manner, and classify its elements according to certain horizons they possess. We also discuss implications of our framework on the firewall problem. We conjecture that the complementarity picture may persist due to properties of trans-Planckian physics. 1 The fundamental scale M * is related to the Planck scale M Pl ≡ 1/l Pl by M 2 Pl ∼ N M 2 * in four dimensions, where N is the number of species existing below M * .

2025, Land …

Reclamation of contaminated land contributes to environmental health by improving the quality of soil and resolving contamination issues, but descriptors of soil health that can be used to recognise quality, identify problems and define endpoints are currently inadequate. There are limited guidelines as to what constitutes a healthy soil. Although the concept has been well discussed in the context of agricultural and forest soils, different indices are probably required for the environmental constraints associated with brownfield land remediation and the creation of new soils. Implicit to restored soil health is the existence of indicators or monitors of biodiversity, soil sustainability and acceptable risk management. This paper considers the relevant biological descriptors of soil health in the search for well-defined and practicable measures of the functional integrity of soils that can be used for management of brownfield sites undergoing restoration to soft end-uses. A current project in Liverpool aims to provide a toolbox of robust descriptors of soil health for practitioners.

2025

A study was conducted in our laboratory along with the routine regulatory testing to evaluate the performance of Biological Reference Preparations (BRP) Human Albumin for Electrophoresis BRP (Code: H0900000, Batch 2, EDQM, France) and Human Immunoglobulin for Electrophoresis BRP (Code: H1000000, Batch 3, EDQM, France) after recommended period i.e fourteen days after reconstitution. These reference preparations are recommended as reference controls for Protein Composition, the test in European Pharmacopoeia (EP)/ Indian Pharmacopoeia (IP) monographs for quality control evaluation of Human Albumin and Human Immunoglobulin preparations intended for therapeutic use. Protein composition by Horizontal Zone Electrophoresis using cellulose acetate membrane strips is a test for determination of purity in these preparations as per EP/IP. The aliquots of these BRP are stored at recommended temperature (20 o C-80 o C) after reconstitution and verified for its performance after fourteen days of recommended period. From the results obtained, it was observed that all data points are within the stated limit for both BRP and significant effect of time period was not observed during the study period, i.e. up to 406th day for human albumin BRP up to 350th day for Immunoglobulin BRP. The %RSD calculated for both BRP is less than 1%. From this study, it is found that these BRP can be used even after fourteen days of the recommended period, if reconstituted and stored as per the instructions of EDQM, France, to avoid wastage of precious certified international reference material.

2025, European Spine Journal

2025, Nonlinear Analysis: Theory, Methods & Applications

Given a ∈ L 1 (R) and the generator A of an L 1 -integrable resolvent family of linear bounded operators defined on a Banach space X, we prove the existence of compact almost automorphic solutions of the semilinear integral equation ]ds for each f : R × X → X compact almost automorphic in t, for each x ∈ X, and satisfying Lipschitz and Hölder type conditions. In the scalar linear case, we prove that a ∈ L 1 (R) positive, nonincreasing and log-convex is sufficient to obtain existence of compact almost automorphic solutions.

2025, Semigroup Forum

Given a ∈ L 1 (R) and A the generator of an L 1 -integrable family of bounded and linear operators defined on a Banach space X, we prove the existence of almost automorphic solution to the semilinear integral equation ]ds for each f : R × X → X almost automorphic in t, uniformly in x ∈ X, and satisfying diverse Lipschitz type conditions. In the scalar case, we prove that a ∈ L 1 (R) positive, nonincreasing and log-convex is already sufficient.

2025, Physical review

The generalized second law of thermodynamics. is applied to fluctuations in the Hawking tem- perature of the cosmological event horizon in de Sitter spacetime. Fluctuations which decrease the temperature, thereby decreasing the scalar curvature, increase the generalized entropy S. Thus, the generalized second law implies that de Sitter space is unstable to fluctuations which decrease the ef- fective cosmological constant.

2025

show that the new derived excitation method is indeed accurate, and can be used for the prediction of the backside radiation and side lobe levels of real life finite ground plane printed antennas. Keywords.-Integral equation, excitation... more

2025, IEEE Transactions on Antennas and Propagation

A new efficient technique for computing the Green's functions inside rectangular waveguides is presented. After a summary of the classical approaches and their difficulties, a new strategy is proposed, based on the decomposition of the main spectral series into simpler terms. Although the resulting series present better convergence rate, several acceleration techniques are combined to further improve the efficiency. Several results are presented to demonstrate the improvements in convergence rates obtained using the new decomposition.

2025

We propose a theoretical framework in which spacetime curvature is extended into the complex domain. In this model, black hole collapse does not result in a singularity of infinite density. Instead, the imaginary components of spacetime curvature serve to disperse and regularize gravitational collapse. This prevents divergence at a point and suggests that the interior of a black hole may contain a complexvalued core with holographic or fractal-like structure. We explore the mathematical structure and implications of complex curvature, arguing that this framework offers a resolution to singularities and a potential bridge to quantum gravity.

2025

Abstract: The extracellular matrix protein 1 (ECM1) is an 85 kDa glycoprotein first identified in 1994. The three-dimensional structure of ECM1 based on the third serum albumin domain was determined by in silico modelling in order to predict the most important binding site(s) of ECM1 with other protein partners in human skin. ECM1 consists of four domains: a first domain existing of -helices (D1), the serum albumin subdomain-like (SASDL) domain 2, the sequence homology comparable with the first subdomain of the third serum albumin domain, SASDL3 and SASDL4, resulting in four “finger-like ” structures ideal for binding with different proteins. A role for ECM1 was proposed in endochondral bone formation, angiogenesis and skin differentiation. Increased evidence has emerged for a pivotal biological function of ECM1 in human skin; loss of function mutations in the ECM1 gene causes the autosomal recessive genodermatosis lipoid proteinosis and auto-antibodies against ECM1 in the auto-immu...

2025

Background: The vast majority of human genes (.70%) are alternatively spliced. Although alternative pre-mRNA processing is modified in multiple tumors, alternative hyper-splicing signatures specific to particular tumor types are still lacking. Here, we report the use of Affymetrix Human Exon Arrays to spot hyper-splicing events characteristic of myasthenia gravis (MG)-thymoma, thymic tumors which develop in patients with MG and discriminate them from colon cancer changes. Methodology/Principal Findings: We combined GO term to parent threshold-based and threshold-independent ad-hoc functional statistics with in-depth analysis of key modified transcripts to highlight various exon-specific changes. These denote alternative splicing in MG-thymoma tumors compared to healthy human thymus and to in-house and Affymetrix datasets from colon cancer and healthy tissues. By using both global and specific, term-to-parent Gene Ontology (GO) statistical comparisons, our functional integrative ad-hoc method allowed the detection of disease-relevant splicing events. Conclusions/Significance: Hyper-spliced transcripts spanned several categories, including the tumorogenic ERBB4 tyrosine kinase receptor and the connective tissue growth factor CTGF, as well as the immune function-related histocompatability gene HLA-DRB1 and interleukin (IL)19, two muscle-specific collagens and one myosin heavy chain gene; intriguingly, a putative new exon was discovered in the MG-involved acetylcholinesterase ACHE gene. Corresponding changes in spliceosome composition were indicated by co-decreases in the splicing factors ASF/SF 2 and SC35. Parallel tumor-associated changes occurred in colon cancer as well, but the majority of the apparent hyper-splicing events were particular to MGthymoma and could be validated by Fluorescent In-Situ Hybridization (FISH), Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and mass spectrometry (MS) followed by peptide sequencing. Our findings demonstrate a particular alternative hyper-splicing signature for transcripts over-expressed in MG-thymoma, supporting the hypothesis that alternative hyper-splicing contributes to shaping the biological functions of these and other specialized tumors and opening new venues for the development of diagnosis and treatment approaches.

2025, Optics Communications

In this work, we present a new lineshape computing method. The lineshape, commonly known as the Voigt profile, is a convolution of the Gaussian and Lorentzian profiles. Moreover, we present a simple approach to describe the width of the Voigt profile as a function of the relative contributions of Gaussian and Lorentzian broadening. A novel expression of the equivalent width of Lorentz shapes can be calculated from numerical approximation.

2025, Fermionic Fields for Curved Spaces

Fermionic Fields for Curved Spaces is a proposal for regularized quantum gravity based on fermionic degrees of freedom. In our lattice model the local Lorentz symmetry is generalized to complex transformation parameters. The difference between space and time is not put in a priori, and the euclidean and Minkowski quantum field theory are unified in one functional integral. The metric and its signature arise as a result of the dynamics, corresponding to a given ground state or cosmological solution. Geometrical objects as the vierbein, spin connection or the metric are expectation values of collective fields built from an even number of fermions. The quantum effective action for the metric is invariant under general coordinate transformations in the continuum limit. The action of our model is found to be also invariant under gauge transformations. We observe a "geometrical entanglement" of gauge-and Lorentz-transformations due to geometrical objects transforming non-trivially under both types of symmetry transformations.

2025

Even when subjects are at rest, it is thought that brain activity is organized into distinct brain states during which reproducible patterns are observable. Yet, it is unclear how to define or distinguish different brain states. A potential source of brain state variation is arousal, which may play a role in modulating functional interactions between brain regions. Here, we use simultaneous resting state functional magnetic resonance imaging and pupillometry to study the impact of arousal levels indexed by pupil area on the integration of large-scale brain networks. We employ a novel sparse dictionary learning-based method to identify hub regions participating in between-network integration stratified by arousal, by measuring k-hubness, the number (k) of functionally overlapping networks in each brain region. We show evidence of a brain-wide decrease in between-network integration and inter-subject variability at low relative to high arousal, with differences emerging across regions...

2025, Advances in Intelligent Systems and Computing

2025

This paper redefines mass as a fifth dimension within the framework of special relativity, introducing Planck-scale corrections to spacetime geometry. We derive modified Lorentz transformations that unify spacetime and mass dynamics, predicting testable deviations at high energies. Experimental validations via particle accelerators and gravitational wave detectors are proposed.

2025, arXiv (Cornell University)

We present a microscopic theory of ground-state spectral function of bilayer quantum Hall systems that includes interactions between Hartree-Fock quasiparticles and quantum fluctuations of the order parameter field. The collective modes in these systems are properly described only when fluctuations in direct and exchange particle-hole channels are taken into account. Using an auxiliary field functional integral approach, we present a generalization of the random phase approximation for quasiparticle self-energy which captures fluctuations in both channels. We discuss its relationship to diagrammatic perturbation theory and an adiabatic approximation. We present simple analytical results for the quasiparticle self-energy and the renormalized order parameter that follow from this theory.

2025, Journal of Contingencies and Crisis Management

This study examines the impact of federal disaster assistance on the survival and success of small family-owned businesses with fewer than 500 employees from 1996 to 1999. Small family-owned business owners were defined as those who had been in business at least a year, had spent a least 6 hours a week or a minimum of 312 hours annually working in the business, had lived with at least one family member and had fewer than 500 employees. This study suggests firms located in counties receiving more disaster assistance are not more likely to survive, however these firms are more likely to realize positive changes in revenue than firms located in counties receiving less disaster assistance. Businesses located in an economically vulnerable rural county, those engaged in family to business resource intermingling and those transferring more business income to the household were more likely to survive. Larger businesses, those headed by women and those transferring more income from the business to the family were most likely to succeed.

2025, NeuroImage

The advent of new signal processing methods, such as non-linear analysis techniques, represents a new perspective which adds further value to brain signals' analysis. Particularly, Lempel-Ziv's Complexity (LZC) has proven to be useful in exploring the complexity of the brain electromagnetic activity. However, an important problem is the lack of knowledge about the physiological determinants of these measures. Although a correlation between complexity and connectivity has been proposed, this hypothesis was never tested in vivo. Thus, the correlation between the microstructure of the anatomic connectivity and the functional complexity of the brain needs to be inspected. In this study we analysed the correlation between LZC and fractional anisotropy (FA), a scalar quantity derived from diffusion tensors that is particularly useful as an estimate of the functional integrity of myelinated axonal fibers, in a group of sixteen healthy adults (all female, mean age 65.56 ± 6.06 years, interval 58-82). Our results showed a positive correlation between FA and LZC scores in regions including clusters in the splenium of the corpus callosum, cingulum, parahipocampal regions and the sagittal stratum. This study supports the notion of a positive correlation between the functional complexity of the brain and the microstructure of its anatomical connectivity. Our investigation proved that a combination of neuroanatomical and neurophysiological techniques may shed some light on the underlying physiological determinants of brain's oscillations.

2025

Barbosa FSS, Almeida CCR, Gonçalves M. 576 dessas particularidades permite intervir de forma mais específi ca na prevenção e reabilitação dos distúrbios da coluna lombar. [P] Palavras-chave: Coluna vertebral. Eletromiografi a. Contração... more

2025, Vision Research

The contrast transfer function (CTF) of the pattern electroretinogram (PERG) depends on temporal frequency. For transient stimulation it is fully linear; at faster stimulation rates it becomes strongly non-linear with an accelerated shape. In this study we investigated a range of stimulus parameters with the aim of studying the influence of temporal and spatial frequencies, as well as contrast levels, on the CTF; effects were quantified via an ''index of linearity'' IL. Both reversal rate and check size influenced linearity (p < .001), examples: At a constant check size of 0.8°, 7.7 rps: IL = 1.0; 0.8°/24 rps: IL = 0.5; at a constant reversal rate of 19 rps, IL was 0.5 for 0.8°, but rose to 0.8 both for 0.2°and 18°. The reason for this complex response surface remains a puzzle, it cannot be explained by varying parvo/ magnocellular contributions, and its possible influences on recordings in patients merit further studies.

2025, Documenta Ophthalmologica

Visual evoked potentials (VEPs) can provide important diagnostic information regarding the functional integrity of the visual system. This document updates the ISCEV standard for clinical VEP testing and supersedes the 2004 standard. The major change in this revision is that test parameters have been made more precise to achieve better consistency of results within and between test centers. The ISCEV standard VEP protocols are defined for a single recording channel with a midline occipital active electrode. These protocols are intended for assessment of prechiasmal function; additional electrode sites are recommended for evaluation of chiasmal and postchiasmal function. ISCEV has selected a subset of stimulus and recording conditions that provide core clinical information and can be performed by most clinical electrophysiology laboratories throughout the world. These are: 1. Pattern-reversal VEPs elicited by checkerboard stimuli with large 1°(i.e., 60 min of arc; min) and small 0.25°(15 min) checks. 2. Pattern onset/ offset VEPs elicited by checkerboard stimuli with large 1°(60 min) and small 0.25°(15 min) checks. 3. Flash VEP elicited by a brief luminance increment, a flash, which subtends a visual field of at least 20°.

2025, PubMed

Malignant tumors of the penis are rare, and constitute only 1% of all tumors in males. The disease is more common in the black population of the USA due to genetic links and the rarity of circumcision. Penile carcinoma is extremely rare in Israel, only 10 cases having been reported during a period of 20 years. Verrucous carcinoma, often called giant condyloma acuminata, constitutes a subgroup of squamous cell carcinoma of the penis. The first description was by Buschke in 1925, and was followed by that of Loewenstein in 1939. The tumor is usually limited to the penile glans and does not invade lymph nodes. We present a 44-year-old Arab with verrucous carcinoma treated by partial amputation of the penis. He had been circumcised 11 years previously. During 18 months of follow-up there was no recurrence.