Spatial Polarization Research Articles

У СИЛЕНИЕ МЕЖРЕГИОНАЛЬНЫХ ВЗАИМОДЕЙСТВИЙ КАК ИНСТРУМЕНТ СНИЖЕНИЯ ПРОСТРАНСТВЕННОЙ ПОЛЯРИЗАЦИИ (НА ПРИМЕРЕ РЕГИОНОВ СЕВЕРО-ЗАПАДНОГО ФЕДЕРАЛЬНОГО ОКРУГА)

This paper is devoted to the analysis of problems and prospects of strengthening interregional interactions. The strengthening of cooperative ties between regions has a beneficial effect not only on technological, but also on the socio- economic and spatial development of regions, thus, it can be considered as a tool to reduce spatial polarization. The article describes the regions of the Northwestern Federal District in the context of spatial polarization, analyzes the instrument of indus- trial and spatial policy – interregional clusters, analyzes the potential for the creation of new interregional clusters in the regions of the Northwestern Federal District based on the current industry specialization and, in general, to strengthen interactions between regions.

Rapid angular ellipsometry method using spatial polarization modulation and detection

Owing to its nanometer accuracy and noninvasive properties, ellipsometry has an important role in the film thickness measurement and optical critical dimension (OCD) method for measuring gratings and semiconductor devices with periodic structures. Currently, commercial ellipsometers frequently take ∼10s to complete a measurement owing to the necessity for mechanically rotating polarized elements, which limits its efficiency. In this paper, we propose a new, to the best of our knowledge, ellipsometry setup that combines a vortex waveplate and a polarized camera to achieve polarization modulation and detection spatially. The measuring speed of the proposed system is determined by the frame rate of the polarized camera. A sample can be rotated to acquire its angular Mueller matrix within 3 s. The theoretical principle is described in this paper. The proposed system was calibrated, and a maximum error of 0.6% was observed when measuring the Mueller matrix of different samples. This proposed method is a simple and rapid method for measuring angular Mueller matrices and will further increase the efficiency of OCD methods and other ellipsometry applications.

Evolution of Resilience Spatiotemporal Patterns and Spatial Correlation Networks in African Regional Economies

This paper comprehensively utilizes the entropy-TOPSIS method, Lyapunov index, and kernel density estimation to measure the spatiotemporal evolution characteristics of regional economic resilience in 52 African countries (regions) from 2008 to 2019. It also examines the spatial network characteristics of regional economic resilience in each country (region) through gravity models and social network analysis. The findings reveal that: (1) Although the resilience of African regional economies fluctuates, it generally shows an improving trend. Traditional economic powers and regional giants such as Libya, Nigeria, South Africa, Egypt, Morocco, and Tunisia demonstrate outstanding performance in economic resilience. (2) In terms of scale resilience, the countries along the North African Mediterranean coast exhibit particularly prominent advantages. However, the overall performance of Africa in fiscal resilience and openness resilience tends to be weak. Industrial resilience is influenced by colonial legacies and tends to stabilize. (3) The differences in economic resilience values and the fluctuation trajectories of economic resilience levels converge. North African economies exhibit resilience far higher than the mean and other regions, while East, West, and Central Africa consistently perform below the mean in the long term. Southern Africa’s gap from the mean is relatively small, leading to a stalemate. The fluctuation amplitude of differences within each region varies. (4) The overall level of resilience in African regional economies has steadily improved, displaying a trend of polarization. There is evident spatial polarization in West Africa, with Southern Africa demonstrating a trend of multipolarity transitioning towards bipolarity. Conversely, North Africa strengthens its features of bipolar differentiation, while East and Central Africa exhibit tendencies towards multipolarity. (5) Despite some fluctuations in the spatial network of regional economic resilience around 2016, connections among African countries have become increasingly tight, gradually forming three major spatial correlation network clusters: the North African Mediterranean coast, the West–Central African Pan-Gulf of Guinea region, and the East–South African Rift Valley region. Nigeria holds a prominent position as a regional core. Zambia, Cameroon, and the Central African Republic have played certain regional core roles at different times. Nigeria and South Africa also demonstrate significant intermediary roles, while Zambia, Cameroon, and Burkina Faso act as bridges in different periods of network connections. Based on the characteristics of spatial correlation networks, African regions gradually form four major cohesive subgroups and eight sub-subgroups.

Advanced Organic–Inorganic Hybrid Materials for Optoelectronic Applications

AbstractResearch on organic–inorganic hybrid materials (OIHMs) has experienced explosive growth in the past decades. The diversity of organic components allows for the introduction of various spatial scales, functional groups, and polarities, while inorganic components provide higher hardness, heat resistance, and stability, their flexible combination facilitates the formation of diverse structures. Furthermore, simple and cost‐effective synthesis methods, such as room temperature solution processes and mechanochemical techniques, enable precise control over the materials' properties at different scales, thus achieving adjustable structure–performance relationships. This review will discuss the recent research progress of OIHMs within the field of optoelectronics and related optoelectronic device applications. According to the dimension of inorganic components and the nature of organic–inorganic interface, this review divides OIHMs into four structural categories. The ongoing research has revealed diverse applications for OIHMs in the fields of solar cells, light‐emitting devices, detectors, and memristors. As an outlook, the potential of perovskite and 0D metal halide materials, which are currently the most studied, for enhancing optoelectronic performance and stability is discussed.

Economic Implications and Public Readiness for Urban Green Space Development in Agra: A Strategic Evaluation in the City of Taj

Urban green spaces (UGSs) improve the environmental value of the city as well as the quality of life for citizens. Unfortunately, many cities in India are lagging behind the minimum standard of UGS required in the city. For example, Agra city in India, one of the most famous tourist destinations in the world, represents two distinct realities of UGS in the same city. One is the focus of tourism, and the rest is the place of common people with very limited public green spaces, leading to multiple social issues (like spatial polarization, etc.). The secondary data concludes that the PPGC of Agra is lower than the standards, and the ongoing schemes are approached through quantitative methods. Despite having many UGS development schemes, Agra's UGS shows stalled growth. This research examines the policies and programs of UGS development (AMRUT, SCM, etc.) and reviews them to understand the unique gaps and possible regulatory interventions. The study includes an assessment of stakeholders' readiness to accept plausible UGS strategies using an analytical analysis approach. The primary data shows that PPP is the requirement for the integrated development of UGSs. The planners can make policies highlighting citizen's rights and responsibilities to enhance UGSs in Agra.

Design terahertz polarizers and vector polarized vortex terahertz wave generators based on the effective dielectric constant of metal gratings

Polarization and phase devices for terahertz waves have important applications in terahertz detection, imaging, communication, etc. Spatially variable metal gratings can be used for broad-spectrum, miniaturized, and low-cost terahertz polarization and phase modulation devices. Based on the effective dielectric constant and the theory of light propagation in multilayer media, we obtain the relationship between the transmittance and extinction ratio and the parameters such as the duty cycle of the metal grating, the frequency of the incident terahertz wave, the angle of incidence, the thickness of the metal grating, the refractive index of the substrate, and the thickness of the substrate. We propose a method of designing a spatially variable metal grating located on a transparent substrate. The designed spatially variable metal grating is also used to modulate the terahertz spatial polarization and phase to generate terahertz optical fields whose polarization and phase change simultaneously in space, such as azimuthally vector vortex terahertz optical fields, radially vector vortex terahertz optical fields, and so on. This will have important applications in terahertz time-domain spectroscopic detection, terahertz time-domain spectroscopic imaging, terahertz time-domain near-field microscopic imaging, terahertz communication, and so on.

Spatial arrangement, polarity, and posttranslational modifications of the microtubule system in the Drosophila eye

We have analyzed the organization of the microtubule system in photoreceptor cells and pigment cells within the adult Drosophila compound eye. Immunofluorescence localization of tubulin and of Short stop, a spectraplakin that has been reported to be involved in the anchorage of microtubule minus ends at the membrane, suggests the presence of non-centrosomal microtubule-organizing centers at the distal tip of the visual cells. Ultrastructural analyses confirm that microtubules emanate from membrane-associated plaques at the site of contact with cone cells and that all microtubules are aligned in distal–proximal direction within the photoreceptor cells. Determination of microtubule polarities demonstrated that about 95% of the microtubules in photoreceptor cells are oriented with their plus end in the direction of the synapse. Pigment cells in the eye contain only microtubules aligned in distal–proximal direction, with their plus end pointing towards the retinal floor. There, two populations of microtubules can be distinguished, single microtubules and bundled microtubules, the latter associated with actin filaments. Whereas microtubules in both photoreceptor cells and pigment cells are acetylated and mono/bi-glutamylated on α-tubulin, bundled microtubules in pigment cells are apparently also mono/bi-glutamylated on β-tubulin, providing the possibility of binding different microtubule-associated proteins.

Graphene Terahertz Devices for Sensing and Communication.

Graphene-based terahertz (THz) devices have emerged as promising platforms for a variety of applications, leveraging graphene's unique optoelectronic properties. This review explores recent advancements in utilizing graphene in THz technology, focusing on two main aspects: THz molecular sensing and THz wave modulation. In molecular sensing, the environment-sensitive THz transmission and emission properties of graphene are utilized for enabling molecular adsorption detection and biomolecular sensing. This capability holds significant potential, from the detection of pesticides to DNA at high sensitivity and selectivity. In THz wave modulation, crucial for next-generation wireless communication systems, graphene demonstrates remarkable potential in absorption modulation when gated. Novel device structures, spectroscopic systems, and metasurface architectures have enabled enhanced absorption and wave modulation. Furthermore, techniques such as spatial phase modulation and polarization manipulation have been explored. From sensing to communication, graphene-based THz devices present a wide array of opportunities for future research and development. Finally, advancements in sensing techniques not only enhance biomolecular analysis but also contribute to optimizing graphene's properties for communication by enabling efficient modulation of electromagnetic waves. Conversely, developments in communication strategies inform and enhance sensing capabilities, establishing a mutually beneficialrelationship.

Tailored Magnetic Spatial Confinement with Enhanced Polarization and Magnetic Response for Electromagnetic Wave Absorption.

For materials with coexisting phases, the transition from a random to an ordered distribution of materials often generates new mechanisms. Although the magnetic confinement effect has improved the electromagnetic (EM) performance, the transition from random to ordered magnetic confinement positions remains a synthetic challenge, and the underlying mechanisms are still unclear. Herein, precise control of magnetic nanoparticles is achieved through a spatial confinement growth strategy, preparing five different modalities of magnetic confined carbon fiber materials, effectively inhibiting magnetic agglomeration. Systematic studies have shown that the magnetic confinement network can refine CoNi NPs size and enhance strong magnetic coupling interactions. Compared to CoNi@HCNFs on the hollow carbon fibers (HCNFs) outer surface, HCNFs@CoNi constructed on the inner surface induce stronger spatial charge polarization relaxation at the interface and exhibit stronger magnetic coupling interactions at the inner surface due to the high-density magnetic coupling units at the micro/nanoscale, thereby respectively enhancing dielectric and magnetic losses. Remarkably, they achieve a minimum reflection loss (RLmin) of -64.54dB and an absorption bandwidth of 5.60GHz at a thickness of 1.77mm. This work reveals the microscale mechanism of magnetic confinement-induced different polarization relaxation and magnetic response, providing a new strategy for designing magnetic materials.

A spatial scientometric analysis of urban planning publications from 2010–2020: geographic disparities in urban planning knowledge production

PurposeThis paper analyzes and illustrates the spatial distribution of publications in international urban planning journals from 2010 to 2020.Design/methodology/approachThe study employs the Biblioshiny bibliometrix package in R to analyze 44,123 articles from 95 international planning journals. To conduct the spatial scientometric analysis, we adopted the United Nations’ geoscheme focusing on three geographical scales: country, subregion, and region. Collaboration patterns at the country and subregional levels were examined using the VOSviewer tool.FindingsThe study found evidence of a spatial polarization of urban planning scholarly knowledge production. Scholars based in the United States and the United Kingdom consistently published at higher rates than any other country in our data set. The region producing the largest number of publications was Europe, consisting of 39.92% of the total publication count. However, urban planning scholars from the Global South authored only 20.96% of planning publications from 2010–2020. Centralization of planning research is also evident within each region and subregion. As such, both the Global North and the Global South should not be framed as homogenous entities and spatial patterns of knowledge production should not be generalized. The analysis also established the emerging role of Northern America as a major collaborator in inter-country and inter-subregional research collaborations. Co-authorship patterns indicate low intra-regional collaboration in planning research, except for Europe.Originality/valueThis article argues that a culture of exclusivity may be occurring in urban planning publication production. By highlighting the spatial disparities in knowledge production, we emphasize the need to examine the structural and institutional barriers that exclude urban planning knowledge emerging from the peripheries in international planning journals.

Three-Dimensionally Printed Agarose Micromold Supports Scaffold-Free Mouse Ex Vivo Follicle Growth, Ovulation, and Luteinization.

Ex vivo follicle growth is an essential tool, enabling interrogation of folliculogenesis, ovulation, and luteinization. Though significant advancements have been made, existing follicle culture strategies can be technically challenging and laborious. In this study, we advanced the field through development of a custom agarose micromold, which enables scaffold-free follicle culture. We established an accessible and economical manufacturing method using 3D printing and silicone molding that generates biocompatible hydrogel molds without the risk of cytotoxicity from leachates. Each mold supports simultaneous culture of multiple multilayer secondary follicles in a single focal plane, allowing for constant timelapse monitoring and automated analysis. Mouse follicles cultured using this novel system exhibit significantly improved growth and ovulation outcomes with comparable survival, oocyte maturation, and hormone production profiles as established three-dimensional encapsulated in vitro follicle growth (eIVFG) systems. Additionally, follicles recapitulated aspects of in vivo ovulation physiology with respect to their architecture and spatial polarization, which has not been observed in eIVFG systems. This system offers simplicity, scalability, integration with morphokinetic analyses of follicle growth and ovulation, and compatibility with existing microphysiological platforms. This culture strategy has implications for fundamental follicle biology, fertility preservation strategies, reproductive toxicology, and contraceptive drug discovery.

Methodological approaches to the assessment of balanced spatial development of regions

Subject. This article discusses the problem of uneven development of regions. Objectives. The article aims to analyze the methods of smoothing spatial polarization and develop an algorithm for assessing the balance of regional development. Methods. For the study, we used a comparative analysis, and the tabular and graphic visualization techniques. Results. The article finds that the processes of polarization are due to socio-economic inequality, and it presents an original methodology for assessing the balance of spatial development, developed on the basis of the cluster approach. Conclusions. At the State level, it is necessary to approve a unified methodology for assessing the balance of Russia's spatial development. When developing programmes for the development of regions, it is necessary to be guided by the concept of leveling spatial imbalances.

Visualizing the Heterogeneity in Homogeneous Supramolecular Polymers.

The dynamic properties of supramolecular polymers enable new functionality beyond the limitations of conventional polymers. The mechanism of the monomer exchange between different supramolecular polymers is proposed to be closely associated with local disordered domains within the supramolecular polymers. However, a direct detection of such heterogeneity has never been experimentally probed. Here, we present the direct visualization of the local disordered domains in the backbone of supramolecular polymers by a super-resolution microscopy technique: Nile Red-based spectrally resolved point accumulation for imaging in nanoscale topography (NR-sPAINT). We investigate the local disordered domains in trisamide-based supramolecular polymers comprising a (co)assembly of benzene-1,3,5-tricarboxamide (BTA) and a variant with one of the amide bonds inverted (iBTA). The NR-sPAINT allows us to simultaneously map the spatial distribution and polarity of the local disordered domains along the polymers with a spatial precision down to ∼20 nm. Quantitative autocorrelation and cross-correlation analysis show subtle differences in the spatial distribution of the disordered domains between polymers composed of different variants of BTA monomers. Further, statistical analysis unraveled high heterogeneity in monomer packing at both intra- and interpolymer levels. The results reported here demonstrate the necessity of investigating the structures in soft materials at nanoscale to fully understand their intricacy.

Thermal Atomic Compass Based on Radially Polarized Beam

AbstractThe relationship between the magnetic field direction and the spatial intensity distribution of a radially polarized light passing through a polarized thermal atom ensemble is investigated, which is intuitively presented in a polarization selection absorption effect of thermal atoms. The radially polarized light has a spatial axisymmetric polarization structure, which is set as the probe beam. If the direction of the applied magnetic field is transformed, the absorption of the alignment atomic system to special polarization components of the probe light is changed, resulting in a different absorption ratio. This allows the 3D vector direction of the magnetic field to be inferred by using only the absorption ratio and the projection coefficient of the transmission intensity pattern. Based on this, this work provides a compass based on a thermal atom system, demonstrating a new method for measuring the magnetic field direction in space.

Interference correction for polarization spectral intensity modulation (PSIM) with spatial heterodyne spectroscopy (SHS)

Spectropolarimetry, capable of measuring both the polarization parameters and spectral information of light, is widely utilized in astrophysical research and atmospheric remote sensing. Spatial Static Polarization Modulation Interferometric Spectroscopy merges polarization spectral intensity modulation (PSIM) with spatial heterodyne spectroscopy to achieve high spectral resolution and static synchronous measurement of continuous band polarization spectral information. This article is based on spatial static polarization modulation interferometric spectroscopy principles and describes correction techniques for non-uniform response and phase errors observed in interferograms. A quantitative relationship was established through simulation between the non-uniform response, phase errors in the interferograms, and the demodulation accuracy of polarization parameters. An experimental setup based on these principles was constructed to validate the effectiveness of the correction. The experimental results demonstrated that by using the reported data processing workflow the error in the degree of polarization was reduced from 0.1354 to 0.0095.

Full-Dimensional Geometric-Phase Spatial Light Metamodulation.

Full-dimensional spatial light modulation requires simultaneous, arbitrary, and independent manipulation of the spatial phase, amplitude, and polarization. This is crucial for leveraging the complete physical dimension resources of light. However, full-dimensional metamodulation can be challenging due to the need for multiple independent control factors. To address this challenge, here we propose parallel-tasking metasurfaces to enable full-dimensional spatial light metamodulation based fully on the geometric-phase concept. Indeed, the meta-atoms are divided into several subphases, each of which serves as an independent control factor to manipulate light phase, amplitude, and polarization through geometric phase, interference, and orthogonal polarization superposition, respectively. Therefore, the macroscopic group of meta-atoms leads to metasurfaces that can achieve broadband full-dimensional spatial light metamodulation, as demonstrated by various types of structured light generation. This approach paves the way to future wide applications of light manipulation enabled by full-dimensional spatial light metamodulation.

Asymmetric spatial competition and dynamics in digitalization: Will public R&D support and marketization exacerbate spatial polarization?

This paper investigates the asymmetric spatial spillover effects of digital development across different types of cities. The results of the two-regime spatial Durbin models, using the panel data of 279 cities in China from 2011 to 2021, reveal the spatial polarization phenomenon in digitalization, where stronger cities such as smart cities, provincial capitals, and port cities become more dominant while weaker cities struggle to catch up. Increasing public R&D support leads to positive spatial spillover effects but exacerbates the spatial “Matthew effect” of digitalization. Additionally, marketization plays a moderating role by enhancing resource allocation efficiency and suppressing negative spatial spillover effects. Higher levels of marketization result in smaller digital gaps between cities. The findings provide valuable insights for decision-makers and stakeholders seeking to foster balanced and inclusive urban development in the digital age.

Research on Optimization Strategies of Regional Cross-Border Transportation Networks—Implications for the Construction of Cross-Border Transport Corridors in Xinjiang

Facility connectivity plays a pioneering role in the Belt and Road Initiative proposed by General Secretary Xi Jinping in 2013. Xinjiang, as the core area of the Silk Road Economic Belt bordering eight Eurasian countries, plays a crucial role in cross-border transportation and humanistic exchanges and is the focus of the national connectivity initiative. While the current analysis on regional accessibility has become more diversified, analyses on long-distance cross-border corridors are still relatively rare. Therefore, this paper takes the Xinjiang Uygur Autonomous Region (XUAR) of China as the main study area extending westward to the five Central Asian countries. Modified accessibility accounting methods and gravity models are used to analyze the current status of accessibility and the strength of economic ties between Xinjiang and the five Central Asian countries. The results showed that the distance decay effect of transportation accessibility between Xinjiang and the five Central Asian countries is obvious; the constraints of “natural geography + transportation economy” affect the accessibility level from each state in Xinjiang to the five Central Asian countries and shows a trend of strength in the north and weakness in the south. From the optimization of the regional planning road network in a reverse projection, G3033 and other highways and the construction of the Yi-A railroad will improve the status quo of “east-west access but not north-south access” in Xinjiang. The “corridor effect” and spatial polarization characteristics of economic connection intensity from Xinjiang to the five Central Asian countries are significant. This study has important theoretical and practical significance for the construction of cross-border corridors.

Generating complex vectorial optical fields via surface lattice resonances.

Vectorial optical fields (VOFs) with extra degrees of freedom hold promise for many photonic applications. However, current methods to generate VOFs are either bulky in size or exhibit limited functionalities. Here, we demonstrate a tunable VOF generator by exciting plasmonic surface lattice resonances (SLRs) with axial symmetry. By meticulously arranging bilayer circular arrays with opposite handedness, we achieve a high Q-factor of 103 via just a few particles despite the general belief that too small array size suppresses the SLRs. This work presents tunable complex VOFs with distinct inhomogeneous spatial polarization distributions, which may enable various applications in integrated and polarization optics.

From global to national: The role of urban agglomerations in China's new development paradigm.

Urban agglomerations (UAs), which serve as pivotal hubs for economic and innovative convergence, play a crucial role in enhancing internal circulation and strengthening external linkages. This study utilizes the China city-level multi-regional input-output tables, incorporating the Dagum Gini coefficient and kernel density estimation methods, to perform a thorough quantitative analysis. Disparities within the national and global value chains ("dual value chains") of Chinese UAs from 2012 to 2017 were assessed. Additionally, the logarithmic mean Divisia index (LMDI) method was applied to disaggregate the drivers of both national and global intermediate inputs (NII and GII). The study's key findings include the following: (1) The national value chain (NVC) within UAs exhibits robust growth, contrasting with the decline in the global value chain (GVC). (2) The inter-UA disparity contribution rate significantly surpasses the combined rates of intra-UA contribution and super-variation density. (3) Distinct evolutionary peak trends are discerned among various UAs within the "dual value chains", highlighting diverse spatial polarization characteristics and expansiveness. (4) The growth of the NVC has transitioned from a negative to a positive impact on NII, while the decline in GVC has substantially counteracted GII growth. Economic and demographic factors notably drive positive improvements in both NII and GII, whereas the efficiency of outflows presents a negative driving effect. Based on these findings, this study offers strategic recommendations to facilitate the effective integration of UAs into the new development paradigm, thereby providing a scientific basis for related decision-making processes.