Functional Approach Research Articles

Potential Near‐Term Wetting of the Southwestern United States if the Eastern and Central Pacific Cooling Trend Reverses

AbstractNear‐term projections of drought in the southwestern United States (SWUS) are uncertain. The observed decrease in SWUS precipitation since the 1980s and heightened drought conditions since the 2000s have been linked to a cooling sea surface temperature (SST) trend in the Equatorial Pacific. Notably, climate models fail to reproduce these observed SST trends, and they may continue doing so in the future. Here, we assess the sensitivity of SWUS precipitation projections to future SST trends using a Green's function approach. Our findings reveal that a slight redistribution of SST leads to a wetting or drying of the SWUS. A reversal of the observed cooling trend in the Central and East Pacific over the next few decades would lead to a period of wetting in the SWUS. It is critical to consider the impact of possible SST pattern trends on SWUS precipitation trends until we fully trust SST evolution in climate models.

Versatile functionalization of Bifidobacteria-derived extracellular vesicles using amino acid metabolic labeling and click chemistry for immunotherapy

Extracellular vesicles (EVs) are nanoparticles secreted by various organisms. Methods for modifying EVs functionally have garnered attention for developing EV-based therapeutic systems. However, most technologies used to integrate these functions are limited to mammalian-derived EVs and a promising modification method for bacteria-derived EVs has not yet been developed. In this study, we propose a novel method for the versatile functionalization of immunostimulatory probiotic Bifidobacteria-derived EVs (B-EVs) using amino acid metabolic labeling and azide-alkyne click reaction. Azide D-alanine (ADA), a similar molecule to D-alanine in bacteria cell-wall peptidoglycan, was selected as an azide group-functionalized amino acid. Azide-modified B-EVs were isolated from Bifidobacteria incubated with ADA. The physicochemical and compositional characteristics, as well as adjuvanticity of B-EVs against immune cells were not affected by azide loading, demonstrating that this functionalization approach can retain the endogenous usefulness of B-EVs. By using the fluorescent B-EVs obtained by this method, the intracellular trafficking of B-EVs after uptake by immune cells was successfully observed. Furthermore, this method enabled the formulation of B-EVs for hydrogelation and enhanced adjuvanticity in the host. Our findings will be helpful for further development of EV-based immunotherapy.

The impacts of spin–orbit coupling and strain on transverse dynamical spin susceptibility in undoped phosphorene: Kane–Mele model study

We present the behaviors of dynamical transverse spin susceptibilities of undoped phosphorene monolayer using the Green’s function approach in the context of Kane–Mele model Hamiltonian. Such dynamical spin susceptibility is proportional to inelastic cross section of neutron beam from the layer. Specially, the effects of magnetic field and spin–orbit coupling strength on the spin excitation modes of phosphorene monolayer are investigated via calculating correlation function of spin density operators. Our results show the increase of magnetic field leads to move the magnetic excitation energy to higher values. Also, the intensity of peaks in inelastic cross section reduces with increase of magnetic field. We also show that applying both uniaxial and biaxial strains causes to decrease the intensity of peaks in dynamical spin susceptibility. Finally the effects of both compressive and tensile strains on frequency dependence of dynamical spin structure factor of phosphorene layer are studied. Moreover, the frequency positions of spin excitation mode of phosphorene layer have been investigated due to the effects of spin orbit coupling strength in details.

Food web collapse and regime shift following goldfish introduction in permanent ponds.

In a global context of invasive alien species (IAS), native predators are often eradicated by functionally different IAS, which may induce complex cascading consequences on ecosystem functioning because of the key role predators play in structuring communities and stabilizing food webs. In permanent ponds, the most abundant freshwater systems on Earth, global human-mediated introductions of alien omnivores such as the pet trade goldfish are driving broad-scale patterns of native predators' exclusion, but cascading consequences on food web structure and functioning are critically understudied. We compared food webs of naturally fishless ponds versus ponds where dominant native predators (newts) had been extirpated by invasive goldfish within the last decade. Integrating community-wide isotopic, taxonomic and functional traits approaches, our study reveals that pond food webs collapsed in both vertical and horizontal dimensions following goldfish introduction and the associated exclusion of native predators. Consumer taxonomic diversity was drastically reduced, essentially deprived of amphibians as well as predatory and mobile macroinvertebrates to the profit of burrowing, lower trophic level consumers (detritivores). Changes in community structure and function underlined a regime shift from a macrophyte-dominated system mainly characterized by benthic primary production (periphyton), to a macrophyte-depleted state of ponds hosting communities mainly associated with phytoplankton primary production and detritus accumulation, with higher tolerance to eutrophication and low dissolved oxygen concentration. Results underline major impacts of widely introduced omnivores such as the goldfish on the functioning of pond ecosystems with potentially dramatic consequences on the key ecosystem services they deliver, such as global biodiversity support or water quality improvement. They also shed light on the key role of submerged aquatic vegetation in supporting diverse communities and complex food webs in shallow lentic systems and call for urgent consideration of threats posed by IAS on ponds' ecosystems by managers and policymakers.

Functional data analysis using deep neural networks

AbstractFunctional data analysis is an evolving field focused on analyzing data that reveals insights into curves, surfaces, or entities within a continuous domain. This type of data is typically distinguished by the inherent dependence and smoothness observed within each data curve. Traditional functional data analysis approaches have predominantly relied on linear models, which, while foundational, often fall short in capturing the intricate, nonlinear relationships within the data. This paper seeks to bridge this gap by reviewing the integration of deep neural networks into functional data analysis. Deep neural networks present a transformative approach to navigating these complexities, excelling particularly in high‐dimensional spaces and demonstrating unparalleled flexibility in managing diverse data constructs. This review aims to advance functional data regression, classification, and representation by integrating deep neural networks with functional data analysis, fostering a harmonious and synergistic union between these two fields. The remarkable ability of deep neural networks to adeptly navigate the intricate functional data highlights a wealth of opportunities for ongoing exploration and research across various interdisciplinary areas.This article is categorized under: Data: Types and Structure > Time Series, Stochastic Processes, and Functional Data Statistical Learning and Exploratory Methods of the Data Sciences > Deep Learning Statistical Learning and Exploratory Methods of the Data Sciences > Neural Networks

Insights into the optoelectronic and thermoelectric properties of defect chalcopyrites XAl2Se4 (X = Zn, Cd, and Hg): A density functional theory approach

In the current study, we employed the full-potential linearized augmented plane wave plus local orbitals (FP-LAPW + lo) approach within the density functional theory (DFT) to investigate the physical properties of Defect Chalcopyrites XAl2Se4 (X = Zn, Cd, and Hg). Calculations yield precise structural and electronic parameters in good agreement with experimental data, revealing all three compounds as direct wide-bandgap semiconductors. The modified Becke-Johan potential (TB-mBJ) method accurately estimates energy gaps, which increase with decreasing lattice constants. The calculated values are 3.34 eV, 3.12 eV, and 2.30 eV for ZnAl2Se4, CdAl2Se4, and HgAl2Se4, respectively. The optical properties, including dielectric function and absorption coefficient, indicate potential applications in visible and ultraviolet optoelectronic devices. The high anisotropy of these materials further enhances their suitability for a range of linear and nonlinear optical applications. Moreover, ZnAl2Se4 exhibits the highest Seebeck coefficient at room temperature. The positive Seebeck coefficient confirmed the p-type behavior of the studied compounds. The highest observed power factor demonstrates optimal thermoelectric performance for these materials. High electrical conductivity values suggest their suitability as effective electrical conductors, especially at elevated temperatures. This study encourages further research into defect chalcopyrites for applications in optoelectronics and thermoelectric energy conversion.

Cerebellar granular neuron progenitors exit their germinative niche via BarH-like1 activity mediated partly by inhibition of T-cell factor.

Cerebellar granule neuron progenitors (GNPs) originate from the upper rhombic lip (URL), a germinative niche in which developmental defects produce human diseases. T-cell factor (TCF) responsiveness and Notch dependence are hallmarks of self-renewal in neural stem cells. TCF activity, together with transcripts encoding proneural gene repressors hairy and enhancer of split (Hes/Hey), are detected in the URL; however, their functions and regulatory modes are undeciphered. Here, we established amphibian as a pertinent model for studying vertebrate URL development. The amphibian long-lived URL is TCF active, whereas the external granular layer (EGL) is non-proliferative and expresses hes4 and hes5 genes. Using functional and transcriptomic approaches, we show that TCF activity is necessary for URL emergence and maintenance. We establish that the transcription factor Barhl1 controls GNP exit from the URL, acting partly through direct TCF inhibition. Identification of Barhl1 target genes suggests that, besides TCF, Barhl1 inhibits transcription of hes5 genes independently of Notch signaling. Observations in amniotes suggest a conserved role for Barhl in maintenance of the URL and/or EGL via co-regulation of TCF, Hes and Hey genes.

Predicting the minimum energy pathway of 1H to 1T phase transition of select 2D transition metal dichalcogenides via density functional theory and machine learning approach

Predicting the minimum energy pathway of 1H to 1T phase transition of select 2D transition metal dichalcogenides via density functional theory and machine learning approach

The stationary Klein-Gordon equation with a delta-like source: A generalized function approach

This work aims to initiate a discussion on finding solutions to non-homogeneous differential equations in terms of generalized functions. For simplicity, we conduct the analysis within the specific context of the stationary Klein-Gordon equation with a point-like source, identifying a generalized function that solves such an equation and aligns with the solution obtained through the Fourier approach with dimensional regularization. In addition to being regular at the source singularity, a notable advantage of our solution is its presentation as a single expression, eliminating the need for piecewise definitions. The arguments presented here are applicable to a broader range of situations, offering a novel approach to addressing divergences in field theories using generalized functions. Moreover, we anticipate that the approach introduced in this work could provide a new method for handling Green functions regularized at coincident points, thereby simplifying the renormalization process in a wide range of theories.

Stabilization of aperiodic sampled-data switched affine systems to hybrid limit cycles

This paper deals with the stabilization of aperiodic sampled-data switched affine systems to a predetermined hybrid limit cycle using a hybrid dynamical system representation and a control Lyapunov function approach. Some preliminaries on the hybrid dynamical system formalism provide the framework for modeling switched affine systems followed by definitions on hybrid limit cycles and related notions. The main result, based on simple Linear Matrix Inequalities (LMI), guarantees that the solutions to the closed-loop system converge to a hybrid limit cycle defined by the states, functioning modes with their corresponding dwell times. The theoretical results are evaluated on academic examples and demonstrate the potential and the originality of the method over the recent literature.

Multi-response optimization in laser processing technologies by applying desirability function approach and response surface methodology based on grey relation analysis

Laser processing technologies are among the leading industry technologies for efficient and economical processing of a wide spectrum of engineering materials. The determination of optimal parameter settings with respect to multiple and opposite process performances is of great practical importance in laser processing technologies. This paper discusses, analyzes, and compares two main approaches for multi-response optimization (MRO) in engineering, that is, desirability function approach (DFA) and grey relation analysis (GRA), while solving five case studies, covering different laser processing technologies, such as cutting, drilling, welding, micro-channeling, and cladding. In each case study the MRO solutions obtained with two competitive approaches were assessed using the relative target deviation (RTD) criterion. Analysis of the obtained MRO solutions and comparative analysis with results from previous studies indicate that the integrated RSM-GRA provide similar and comparable solutions with the hybrid Taguchi method and GRA, while DFA proved to be a better and more promising approach for solving MRO in laser processing technologies. Some specific features, limitations, and possibilities of MRO approaches were also discussed.

Structural, electronic, mechanical and magnetic properties of AFeAs (A: Li, Na and K) pnictides: A density functional approach

In this comprehensive investigation, the physical (electronic, structural and magnetic) and mechanical characteristics of AFeAs (A = Li, Na, K) are examined by using first principle approximations. Employing optimized cell parameters, bulk modulus, phase stability and correlation of them with magnetic order is also reported. The equation of state described the existence of an antiferromagnetic ground state. The effects of structural alterations on electronic characteristics for all nonmagnetic and magnetic systems are also covered here. The mechanical stability and metallic nature of all AFeAs is revealed from the mechanical features and the electronic band diagram. The orbital partial density of state having mixed orbital containing degenerate 3dzx and 3dzy orbitals of the Fe-3d state are also discovered. Additionally, as many features of the stable KFeAs system were not previously quantified so, a comparative picture of KFeAs with the other two representatives (NaFeAs and LiFeAs) of A-111 groups is also provided.

Investigation on molecular and biomolecular spectroscopy of the novel 2BCA molecule to analyse its biological activities and binding interaction with nipah viral protein

The molecule of 2-Biphenyl Carboxylic Acid (2BCA), which contains peculiar features, was explored making use of density functional theory (DFT) and experimental approaches in the area of quantum computational research. The optimised structure, atomic charges, vibrational frequencies, electrical properties, electrostatic potential surface (ESP), natural bond orbital analysis and potential energy surface (PES) were obtained applying the B3LYP approach with the 6–311++ G (d,p) basis set.. The 2BCA molecule was examined for possible conformers using a PES scan. The methods applied for spectral analyses included FT-IR, FT-RAMAN, NMR, and UV–Vis results. Vibrational frequencies for all typical modes of vibration were found using the Potential Energy Distribution (PED) data. The UV–Vis spectrum was simulated using the TD-DFT technique, which is also seen empirically. The Gauge-Invariant Atomic Orbital (GIAO) approach was employed to model and study the 13C and 1H NMR spectra of the 2BCA molecule in a CDCL3 solution. The spectra were then exploited experimentally to establish their chemical shifts. To predict the donor and acceptor interaction, the NBO analysis was used. The electrostatic potential surface was employed to anticipate the locations of nucleophilic and electrophilic sites. Hirshfeld surfaces and their related fingerprint plots are exploited for the investigation of intermolecular interactions. Reduced Density Gradient (RDG) helps to measure and illustrate electron correlation effects, offering precise insights into chemical bonding, reactivity, and the electronic structure of 2BCA. According to Lipinski and Veber’s drug similarity criteria, 2BCA exhibits the typical physicochemical and pharmacokinetic properties that make it a potential oral pharmaceutical candidate. According to the findings of a molecular docking study, the 2BCA molecule has promise as a treatment agent for the Nipah virus (PDB ID: 6 EB9), which causes severe respiratory and neurological symptoms in humans.

Conceptual Properties of Islamic Economic Modeling: Complexity, Nonlinearity, and Endogeneity in Epistemological Perspectives

This paper introduces a new perspective of economic reasoning and analysis pertaining to situations of complexity combined with nonlinearity and endogenous relations among interacting, integrating and evolutionary entities. The entities comprise multi-variables representing different embedded systems that encompass economy, society, science, and ethics. In the emergent model of endogenous inter-causal relationships between such entities the ontological perspective assumes the nature of evaluating inter-causal intra- and inters- systemic relations by means of formalism belonging to functional ontology of mathematical forms (Gruber, 1993), as opposed to invoking metaphysical ontological speculation. The functional ontological approach to structure and formalize leads to a new framework of economic reasoning in the presence of embedded systems that continuously participate and complement, as opposed to being subjected to the central postulate of marginal rate of substitution and exogenous treatment of knowledge in mainstream economics. The continuous phenomenon of interaction, integration, and evolutionary (IIE) learning in such inter-causal systems establish ethical endogeneity. Thus, philosophical background of economic reasoning is invoked in the functional epistemological formalism of the interactive, integrative, and evolutionary systems. That is sush systems are characterized by IIE-learning processes induced by the episteme of unity of knowledge.

The functional approach to grammatical thought according to Abu Ali Al-Farsi

كانت الأحكام النّحويّة التي يطلقها أبو عليّ الفارسيّ تؤكد الجانب الوظيفي للغة ، إذ لم يقتصر في أحكامه على الجانب الشّكلي للتراكيب النّحويّة بل استطاع أن يوازن بين الشّكل والوظيفة ؛ لبيان المهمة الرئيسة للغة في حيز التّواصل الإنساني ، وقد رفض كثيرًا من الأحكام والمصطلحات والحدود معتمدًا على الوظيفة النّحويّة التي تؤديها المفردات داخل التركيب النّحوي ؛ ليبين أنّ وظيفة النحو لا تتحقق بتعلم القوانين النّحويّة الجامدة بل تتحقق بوساطة اتقان نظام اللغة ، وأساليبها في التّعبير.

Technology development of novel autogenous double pulse tungsten insert gas welding technique to evaluate the depth of penetration, micro segregation via machine learning and desirability function approach

The present research investigates the effect of process parameters on the microstructure, micro segregation, and material properties of the Autogenous Double Pulse Tungsten Inert Gas Welding (ADP-TIG) of Inconel 625. The optimization of the process parameter was evaluated by Response surface Methodology (RSM) Box Behnken method. In this article, the effects of the weld-bead geometry, weld centre (WC), weld interface (WI), and heat affected zone (HAZ) were evaluated through macro morphology, microstructure, SEM/EDAX, XRD, and micro hardness. The outcomes indicate that by employing a combination of high and low frequency pulsing in ADP-TIG, it is possible to regulate not only the dimensions of the weld-bead and penetration depth but also the HAZ. The ADP-TIG process has a low heat input, resulting in finer grains in the microstructure, reduced secondary phases, and a narrower HAZ. SEM images of alloy 625 confirms the depiction of fine equiaxed dendrites. The ADP-TIG process reduces secondary phase formation due to a reduction in Mo and Nb alloying elements. EDAX results also show that the micro segregation in the weld centre (WC) and weld interface (WI) is very less in the dendritic core region because of the lower heat Input. The XRD result confirms the presence of NbzNi, Cr₂Nb, Ni8Nb, Fe2Mo3 and FeNi phases. The maximum microhardness values in WC and WI are 290 HV and 280 HV, respectively. The impacts of ADP-TIG welding technique specifications on factors such as weld bead geometry, WC, WI, and HAZ have been thoroughly examined across a range of process parameters. Further the process parameters of ADP-TIG were optimized using a desirability function to achieve defect-free welds, followed by experimental validation. The desirability function results were then compared with a machine learning (ML) approach. The investigation aimed to assess ML algorithms' predictive capability for weldment outcomes. From the ML modelling results, Support Vector Machine (SVM) using the Radial Basis Function (RBF) kernel was identified as the superior strategy for accurately predicting Heat input, Mo segregation, and Nb segregation. Additionally, Gaussian process regression (GPR) with an RBF kernel was recommended for predicting the Width to Depth Ratio.

Inclusion of Nonresonant Effects Into Quasi‐Linear Diffusion Rates for Electron Scattering by Electromagnetic Ion Cyclotron Waves

AbstractElectromagnetic ion cyclotron (EMIC) waves are a key plasma mode affecting radiation belt dynamics. These waves are important for relativistic electron losses through scattering and precipitation into Earth's ionosphere. Although theoretical models of such resonant scattering predict a low‐energy cut‐off of ∼1 MeV for precipitating electrons, observations from low‐altitude spacecraft often show simultaneous relativistic and sub‐relativistic electron precipitation associated with EMIC waves. Recently, nonresonant electron scattering by EMIC waves has been proposed as a possible solution to the above discrepancy. We employ this model and a large database of EMIC waves to develop a universal treatment of electron interactions with EMIC waves, including nonresonant effects. We use the Green's function approach to generalize EMIC diffusion rates foregoing the need to modify existing codes or recompute empirical wave databases. Comparison with observations from the electron losses and fields investigation mission demonstrates the efficacy of the proposed method for explaining sub‐relativistic electron losses by EMIC waves.

Gender preference in China: A study with indirect utility function

The traditional view is that China is a strong son preference country, and some empirical studies support such view. We argue that demand for children, including sex of children, and family size, is the outcome of economic decisions in which social and economic factors could interact with gender preference. Thus, it is possible that strong social and economic factors counteract the strong son preference and lead to daughter preference. To investigate this possibility, we propose an indirect utility function approach and apply it to a recent Chinese data set. We find strong evidence on preference reversal as incomes and child rearing costs rise substantially for Chinese urban parents. Given that China is now a middle-income country and child rearing costs have skyrocketed during the last four decades, we find that Chinese parents with one child have little interest in rushing to have a second child. This does not bode well for the Chinese government’s programs to improve demographics.

Quantum Gravity Corrections to the Inflationary Spectrum in a Bohmian Approach

A precise interpretation of the universe wave function is forbidden in the spirit of the Copenhagen School since a precise notion of measure operation cannot be satisfactorily defined. Here, we propose a Bohmian interpretation of the isotropic universe quantum dynamics, in which the Hamilton–Jacobi equation is restated by including quantum corrections, which lead to a classical trajectory containing effects of order ℏ2. This solution is then used to determine the spectrum of gauge-invariant quantum fluctuations living on the obtained background model. The analysis is performed adopting the wave function approach to describe the fluctuation dynamics, which gives a time-dependent harmonic oscillator for each Fourier mode and whose frequency is affected by the ℏ2 corrections. The properties of the emerging spectrum are discussed, outlining the modification induced with respect to the scale-invariant result, and the hierarchy of the spectral index running is discussed.

Recreational Space as the Embodiment of the Garden of Eden Archetype

The purpose of the article is to research the spiritual basis and motivation of human activity in the relationships between humans and the natural environment to create various forms of recreational spaces in the socio-cultural context of the post-industrial era. Theoretical basis. The research is based on the approach of analytical psychology by C. Jung, who identified the archetypes of the collective unconscious. These archetypes help overcome the limitations of the functional and pragmatic approach, which is focused on mere survival. They make sense and provide values in the relationship between humans and nature. Originality. The article evaluates how archetypal images of the collective unconscious, with the help of the Garden of Eden image in the socio-cultural context of European civilization, influence the recreational space in contemporary urban environments. The novelty of the work is also in the interdisciplinary approach, integrating knowledge from various fields such as philosophy, sociology, cultural studies, analytical psychology, and urban planning, which contributes to the profound understanding of complex socio-cultural processes. This paradigm emphasizes the interconnection and interdependence, adaptability, and co-evolution of society and nature, as well as requires the interdisciplinary methodological approach. Additionally, the article presents a fresh perspective on nature and its elements in terms of their importance both for individuals and society. Conclusions. The article investigates the socio-cultural factors that evoke the interest of man and society in natural factors as a recreational resource and determine the latest theoretical approaches to their use. Various recreational activities to create a renewed space provide a person with a full physical, socio-psychological and cognitive development. The humanization of the natural environment becomes the embodiment of the collective memory and history of mankind. The recreational space symbolizes spiritual values, so it is transformed from physical to socio-cultural and provides theoretical approaches to its implementation in modern urban planning practices.