Search Results (164)

With the rapid advance of digital technologies, the service industry has become a key driver of sustainable economic growth and the restructuring of international trade. Drawing on value-added trade flows for five pivotal service industries—construction, air transportation, postal telecommunications, financial intermediation, and education—over 2013–2021, this study examines the spatial evolution of the global service value chain (GSVC). Using social network analysis combined with a Temporal Exponential Random Graph Model (TERGM), we assess the dynamics of the GSVC’ core–periphery structure and identify heterogeneous determinants shaping their spatial networks. The findings are as follows: (1) Exports across the five industries display an “East rising, West declining” pattern, with markedly heterogeneous magnitudes of change. (2) The construction industry is Europe-centered; air transportation exhibits a U.S.–China bipolar structure; postal telecommunications show the most pronounced “East rising, West declining” shift, forming four poles (United States, United Kingdom, Germany, China); financial intermediation contracts to a five-pole core (China, United States, United Kingdom, Switzerland, Germany); and education becomes increasingly multipolar. (3) The GSVC core–periphery system undergoes substantial reconfiguration, with some peripheral economies moving toward the core; the core expands in air transportation, while postal telecommunications exhibit strong regionalization. (4) Digital technology, foreign direct investment, and manufacturing structure promote network evolution, whereas income similarity may dampen it; the effects of economic freedom and labor-force size on spatial network restructuring differ significantly by industry. These results underscore the complex interplay of structural, institutional, and geographic drivers in reshaping GSVC networks and carry implications for fostering sustainable services trade, enhancing interregional connectivity, narrowing global development gaps, and advancing an inclusive digital transformation. Full article

Linear cultural heritage poses significant challenges in tourism development, primarily due to the complexities involved in implementing scientific zoning and differentiated management strategies. Systematic optimization of its tourism spatial structure has thus become crucial for achieving sustainable utilization. This study adopts a case study approach based on deductive reasoning to examine the morphological characteristics and evolutionary patterns of the tourism space along linear cultural heritage. Taking the Beijing–Hangzhou Grand Canal as an example, it proposes a targeted optimization pathway from a spatial positioning perspective. The findings indicate that the tourism value of linear cultural heritage exhibits a “vine-shaped structure” spatially, and the development process of the tourism space structure follows the “growth pole” evolution law. Moreover, spatial optimization can be achieved through the dual dimensions of spatial form and utilization intensity. Based on this pathway, a three-level tourism zone system is constructed for the Beijing–Hangzhou Grand Canal: the primary tourism zone, located in southern sections, such as Yangzhou and Hangzhou, serves as leading regions that play a pivotal and driving role; the secondary tourism zone, encompassing Beijing, Tianjin, Langfang, and Cangzhou, requires focused enhancement and functional upgrading; and the tertiary tourism zone, mainly including Shandong Province and Xuzhou, Suqian, in Jiangsu Province, necessitate comprehensive and integrated development to achieve overall improvement. This classification not only facilitates coordinated tourism development along the entire canal from a holistic perspective but also provides a basis for formulating targeted strategies for segments with varying tourism values and utilization intensities. Full article

Improving the isotropic magnetic properties of FeSi electrical steels has traditionally focused on enhancing their crystallographic texture and microstructural morphology. Strengthening the cube texture within a ferritic matrix of optimal grain size is known to reduce core losses and increase magnetic induction. However, conventional cold rolling followed by annealing remains insufficient to optimise the magnetic performance of thin FeSi strips fully. This study explores an alternative approach based on grain boundary migration driven by temperature gradients combined with deformation gradients, either across the sheet thickness or between neighbouring grains, in thin, weakly deformed non-oriented (NO) electrical steel sheets. The concept relies on deformation-induced grain growth supported by rapid heat transport to promote the preferential formation of coarse grains with favourable orientations. Experimental material consisted of vacuum-degassed FeSi steel with low silicon content. Controlled deformation was introduced by temper rolling at room temperature with 2–40% thickness reductions, followed by rapid recrystallisation annealing at 950 °C. Microstructure, texture, and residual strain distributions were analysed using inverse pole figure (IPF) maps, kernel average misorientation (KAM) maps, and orientation distribution function (ODF) sections derived from electron backscattered diffraction (EBSD) data. This combined thermomechanical treatment produced coarse-grained microstructures with an enhanced cube texture component, reducing coercivity from 162 A/m to 65 A/m. These results demonstrate that temper rolling combined with dynamic annealing can surpass the limitations of conventional processing routes for NO FeSi steels. Full article

Background/Objectives: Vertical ridge augmentation remains a challenging procedure in alveolar bone reconstruction, with existing techniques often limited by surgical complexity, graft instability, and high resorption rates. This study evaluates the clinical and histological outcomes of a novel vertical ridge augmentation technique using a wide-head tenting pole screw (WHTPS) combined with sticky bone graft material. Methods: Five patients with vertical bone deficiencies (6–10 mm) in the maxilla or mandible underwent augmentation using a single WHTPS (rectangular or round wide-head type). Sticky bone was prepared using autologous tooth bone, allografts, or xenografts, combined with fibrin glue and covered with concentrated growth factor (CGF) membranes and/or resorbable collagen membranes. After 5–6 months of healing, the WHTPS was removed, and bone biopsies were taken for histological analysis. Results: Radiographic and histological evaluations confirmed successful ridge augmentation in all cases. Newly formed bone ranged from 21.2% to 57.5%. All patients proceeded to implant placement without complications. Radiographic, clinical, and histological assessments consistently showed that new bone formation extended up to the level of the screw head, indicating complete vertical fill of the augmented space. Histology showed well-integrated, mineralized bone with no signs of inflammation. The wide-head tenting pole screw was observed to support stable space maintenance and facilitate surgical handling and favorable outcomes in vertical ridge augmentation. Conclusions: In this case series, a single wide-head tenting pole screw appeared sufficient to maintain space and resist soft tissue pressure in wide alveolar bone defects during healing. This case series suggests that the wide-head tenting pole screw technique may be a feasible option for managing severe alveolar bone deficiencies. Full article

Background: Although adolescents are at a lower risk of developing scaphoid non-union than adults, this complication is not uncommon in younger patients. The current gold standard for surgical treatment is non-vascularized bone grafting from the iliac crest or distal radius, and it is often considered the first-line option. However, non-union can persist in 10–20% of cases, and failure rates can reach up to 50% when the proximal pole is necrotic. Methods: We evaluated a modified vascularized bone graft surgical technique in selected adolescent patients, with the goal of avoiding growth-related complications. Our experience is based on three cases of scaphoid non-union treated surgically between June 2019 and June 2022. Results and Conclusions: The modified surgical technique has shown promising results in the selected cases and carries no risk of donor site morbidity. It enables preservation of severely compromised scaphoid bones, prevents early-onset wrist osteoarthritis, and facilitates the return to sports activities for young patients. Full article

Background and Objectives: Currently, infertility is one of the major problems affecting up to 12% of couples worldwide, with more than a quarter of cases being male-related. It is assumed that Leukocyte-poor platelet-rich plasma (LP-PRP) can improve the function of germ cells and serve as a regenerative substrate as a source of biologically active substances that play an important role in the process of spermatogenesis in infertile men. We aimed to evaluate the proliferation, apoptosis, and growth factors of germ cells after the administration of LP-PRP in patients with non-obstructive azoospermia. Materials and Methods: The study used archival material (paraffin blocks of testicular biopsies) of patients with non-obstructive azoospermia aged 21–34 years (n = 41; associated diagnosis: varicocele). We confirm that no interventions or biopsies were performed as part of the study itself. They were injected bilaterally into the spermatic cord and in the region of the lower pole of the testis under ultrasound control were injected with PRP once a week for 6 weeks. Biopsies were immunohistochemical reactions with antibodies to Ki-67, Bcl-2, caspase 3 and p53, IGF-1, TGF-β, and VEGF-A. Results: Immunohistochemical study of testicular biopsies after LP-PRP injection revealed an increase in the number of cells stained for proliferation proteins (Ki-67) and anti-apoptosis (Bcl-2), IGF-1, TGF-β, VEGF-A; decrease caspase-3- and p53-positive cells. Conclusions: In LP-PRP, platelet α-granule growth factors, which are key regulators of the cell cycle of germ cells, demonstrate restoration of the proliferative-apoptotic balance, confirmed by the expression levels of Ki-67, Bcl-2, caspase 3, and p53 in patients with non-obstructive azoospermia. In human testicular biopsies, the administration of LP-PRP led to an exponential release of numerous growth factors from platelet α-granules, which, based on their regenerative properties, improved the morphological and immunohistochemical picture of the germinal epithelium in non-obstructive azoospermia. Full article

The Qinghai–Tibetan Plateau (QTP), often referred to as the “Third Pole” of the world, harbors alpine grassland ecosystems that play an essential role as global carbon sinks, helping to mitigate the pace of climate change. Nonetheless, alterations in natural environmental conditions coupled with escalating human activities have disrupted the seasonal growth cycles of grasslands, thereby intensifying degradation processes. To date, the key drivers and lifecycle dynamics of Grassland Depletion across the QTP remain contentious, limiting our comprehension of its ecological repercussions and regulatory mechanisms. This study comprehensively investigates grassland degradation on the Qinghai–Tibetan Plateau, analyzing its drivers and changes in ecological suitability during the growing season. By integrating natural factors (e.g., precipitation and temperature) and anthropogenic influences (e.g., population density and grazing intensity), it examines observational data from over 160 monitoring stations collected between the 1980s and 2020. The findings reveal three distinct phases of grassland degradation: an acute degradation phase in 1990 (GDI, Grassland Degradation Index = 2.53), a partial recovery phase from 1996 to 2005 (GDI < 2.0) during which the proportion of degraded grassland decreased from 71.85% in 1990 to 51.22% in 2005, and a renewed intensification of degradation after 2006 (GDI > 2.0), with degraded grassland areas reaching 56.39% by 2020. Among the influencing variables, precipitation emerged as the most significant driver, interacting closely with anthropogenic factors such as grazing practices and population distribution. Specifically, the combined impacts of precipitation with population density, grazing pressure, and elevation were particularly notable, yielding interaction q-values of 0.796, 0.767, and 0.752, respectively. Our findings reveal that while grasslands exhibit superior carbon sink potential relative to forests, their productivity and ecological functionality are undergoing considerable declines due to the compounded effects of multiple interacting factors. Consequently, the spatial distribution of ecologically suitable zones has contracted significantly, with the remaining high-suitability regions concentrating in the “twin-star” zones of Baingoin and Zanda grasslands, areas recognized as focal points for future ecosystem preservation. Furthermore, the effects of climate change and intensifying anthropogenic activity have driven the reduction in highly suitable grassland areas, shrinking from 41,232 km² in 1990 to 24,485 km² by 2020, with projections indicating a further decrease to only 2844 km² by 2060. This study sheds light on the intricate mechanisms behind Grassland Depletion, providing essential guidance for conservation efforts and ecological restoration on the QTP. Moreover, it offers theoretical underpinnings to support China’s carbon neutrality and peak carbon emission goals. Full article

The Chaoshan Depression, situated in the northern South China Sea, is a Mesozoic residual depression beneath the Cenozoic Pearl River Mouth Basin. Borehole LF35-1-1 has confirmed the existence of marine Jurassic layers rich in organic carbon within this depression. However, the understanding of petroleum geology in this area is limited due to the complex interplay of Mesozoic and Cenozoic tectonic activities and the poor quality of seismic imaging from previous surveys, which have obstructed insights into the characteristics of Mesozoic reservoirs and the processes of oil and gas accumulation. Recent quasi-3D seismic data have allowed for the identification of Mesozoic bioherms and carbonate platforms in the Middle Low Uplift of the Chaoshan Depression. This research employs integrated geophysical data (MCS, gravity, magnetic) and well data to explore the factors that influenced Middle Jurassic reef development and their implications for reservoir formation. The seismic reflection patterns of reefs and carbonate platforms are primarily characterized by high-amplitude discontinuous to chaotic reflections, with occasional blank reflections or weak, sub-parallel reflections, as well as significant high-velocity, high Bouguer gravity and low reduced-to-pole (RTP) magnetic anomalies. Atolls, stratiform reefs, and patch reefs are located on the local topographic highs of the platform. Three vertical evolutionary stages have been identified based on the size of atolls and fluctuations in relative sea level: initiation, growth, and submergence. The location of bioherms and carbonate platforms was influenced by paleotectonic topography, while their horizontal distribution was affected by variations in relative sea level. Furthermore, the reef limestone reservoirs from the upper member of the Middle Jurassic, combined with the mudstone source rocks from the Lower Jurassic and the lower section of the Middle Jurassic, as well as the bathyal mudstone caprocks from the lower part of the Late Jurassic, create highly favorable conditions for hydrocarbon accumulation. Full article

This study presents a prospective evaluation of adrenal gland development in a cohort of Beagle puppies, utilizing sonographic imaging and functional assessment of the basal serum cortisol concentrations. The objective was to characterize the growth patterns and physiological maturation of the adrenal glands in dogs between six and twelve months of age. Ten Beagle puppies from two litters, bred and maintained under standardized conditions at the Veterinary Teaching Hospital in Hannover, were included in the study. Serum cortisol levels were determined, and adrenal gland dimensions were measured using ultrasonography at regular intervals over a six-month observation period. The results demonstrated a significant growth trajectory of the adrenal glands, characterized by notable increases in both the longitudinal length and caudal pole diameter. No significant correlation was found between serum cortisol levels and adrenal gland size, indicating that the cortisol data primarily served to confirm the physiological function of the adrenal glands rather than to influence their size. The adrenal gland sizes mostly resembled those of adult animals; however, significant growth was observed between 6 and 12 months. In conclusion, the presence of small adrenal glands in young dogs with clinical suspicion should prompt further diagnostic testing or, at least, regular follow-up evaluations. Full article

The development of sci-tech parks (STPs), as the spatial carrier of urbanization and the growth pole of the innovation economy, cannot be separated from the integration of the three key elements of “industry”, “city”, and “innovation”. This study selects the Hangzhou West Hi-Tech Corridor, which represents the forefront of development practice of China’s STPs and which is a high-quality model with highly integrated “industry–city–innovation” functions, as a case. By using multi-source data, such as geographic information and the point of interest (POI), and research methods, such as the Shannon entropy index and quadratic curve regression, this study examines the influence of “industry–city–innovation” functional mixing on the innovative development of STPs, and explores the optimal mixing degree interval. The results show that the mixing of “industry–city–innovation” functions can promote the STPs’ innovative development, to a certain extent, in the spatial design of urban planning. However, higher mixing is not always better, and excessively high mixing may inhibit innovative development. The optimal functional mixing degree conducive to the STPs’ innovative development is in the range of 0.14 to 0.16. This study is an effective application of the “industry¬–city–innovation” integration theory, provides a constant source of power for urban innovative development, and acts as a reference for future new cities and STPs. Full article

The microstructure of bivalve foliated calcite is extraordinary. It consists of units formed of stacks of folia with individual folia consisting of arrowhead-ended crystal laths. We investigated the texture of the foliated microstructure, the texture of individual and arrays of folia and the texture of assemblies of foliated units of the gryphaeid oyster Hyotissa hyotis with low kV, high-resolution, electron backscatter diffraction (EBSD). We base our understanding of the foliated texture on the combined interpretation of crystallographic aspects of individual and stacks of folia with the nature of crystal organization in a folium, a foliated unit and in foliated unit aggregations. Calcite c- and a*-axes arrangement in a folium is single-crystal-like. Due to the parallel organization of adjacent laths in a folium and the stacked arrangement of folia in a foliated unit, the assembly of calcite c- and a*-axes in foliated units is graded. The result is a ring-like distribution of c- and a*-axes orientations in the pole figures; nonetheless, the orientation rings are substructured by c- and a*-axes orientation clusters. The direction of the arrowhead endings of the laths is coincident with the growth direction of the shell. The morphology of arrowheaded laths initiates the formation of planes with {105}, {106} directions and a parallel orientation to the inner shell surface. H. hyotis’s foliated microstructure has a specific texture that is not fully understood. We discuss axial, spherulitic, turbostratic-like textures the foliated microstructure and suggest that the foliated texture of H. hyotis can, to some degree, be described with a turbostratic pattern. Full article

Temporary permeable structures of bamboo and brushwood have been implemented for mangrove restoration along retreating coastlines worldwide. However, deriving lessons from previous studies is inhibited by their lack of morphodynamic context, with missing bathymetric data or control comparisons. In this paper, we present a low-tech, low-cost, data collection methodology to support morphodynamic system understanding and modeling of mangrove coastlines. This method was applied to monitor a mangrove restoration project featuring temporary permeable structures of bamboo and PVC, installed in late 2021 on the subsiding muddy coast of Demak, Indonesia. Seabed level changes were regularly tracked with bathymetric surveys and monitoring poles across structures and at a nearby control site. Structures were positioned landward of a chenier, at −0.7 m to −0.9 m relative to mean sea level (MSL), and 30–70 m seaward of the mangrove fringe. Measurements from August 2021 to December 2022 revealed seabed erosion (−0.33 m to −0.4 m) seaward of the structures, with mixed responses landward: two sections eroded (−0.04 m to −0.05 m), one remained stable, and a creek-adjacent section eroded by −0.43 m. At the nearby control site, chenier migration and vertical growth promoted landward accretion, though elevations remained below MSL and thus unsuitable for mangrove colonization. The bathymetric and monitoring pole measurements presented in this study constitute valuable datasets for modeling studies aiming to unravel the dominant processes driving morphodynamic changes. Such models could also inform integrated approaches to mangrove restoration in subsiding coastlines, considering sediment supply, subsidence management, and structure integrity. Full article

Magnetorheological (MR) brakes are flourishing in low-torque applications due to their dynamic controllability nature. Researchers have introduced multi-layer and multipole concepts to increase the torque–volume ratio (TVR) of the MR brake. However, the combination of these two ideas did not exist due to the design limitations. Therefore, this study aims to design a brake that combines the multipole magnetic field and multi-layered structure concepts. The axial slots were introduced on the brake rotor and the stator drum axial surfaces to achieve a high TVR. These slots stop the flux bypass in the inner layers; therefore, the magnetic flux can also reach the brake’s outer layers. This brake was designed with multiple stator and rotor drums and MR fluid layers. The number of poles was placed so that the magnetic field from these poles traveled in a closed loop via the stator, rotor, and MR layers. A 3D model of the brake was prepared for the virtual study. Electromagnetic simulations were conducted to analyze the effect of axial slots’ and other design parameters of the brake. According to those simulation results, the axial slots’ width and position significantly affect the brake output torque. The maximum torque obtained from the brake is 38 Nm, and the TVR value of the brake is 41 Nm/dm³. Additionally, multiphysics simulations were performed to understand the Joule-heating effect of the magnetic coil and the frictional heating in MR fluid. Results showed that the maximum possible temperature in the brake is under the MR fluid temperature limits. Therefore, this multipole multi-layered (MPML) MR brake with axial slots idea is very useful for high-torque MR brake growth. Full article

Eliminating poverty, reducing inequality, and achieving balanced development are one of the United Nations Sustainable Development Goals. Objectively and accurately measuring regional economic vitality and development equilibrium is a pressing scientific issue that needs to be addressed in order to achieve common prosperity. Nighttime light (NTL) remote sensing data have been proven to be a good proxy variable for socio-economic development, and are widely used due to their advantages of convenient access and wide spatial coverage. Based on multi-source data, this study constructs an Economic Development Index (EDI) that comprehensively reflects regional economic vitality from two aspects, economic quality and development potential, combines the Nighttime Light Development Index (NLDI) as the evaluation indicators to measure the economic vitality and development equilibrium, analyzes the economic vitality and development equilibrium of 300 district and county units in China’s three major urban agglomerations from 2000 to 2020 and their temporal and spatial variation characteristics, and discusses the connotation of EDI and its availability. The results show the following: (1) From 2000 to 2020, the average growth rate of EDI in China’s three major urban agglomerations reached 36.32%, while the average decrease rate of NLDI reached 38.75%; both economic vitality and the development equilibrium have been continuously enhanced. Among them, the Yangtze River Delta (YRD) urban agglomeration experienced the fastest economic growth, while the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) exhibited the strongest economic strength. (2) Both economic vitality and the development equilibrium in these three urban agglomerations exhibited distinct spatial agglomeration characteristics, namely center-surrounding distribution, coastal–inland distribution, and radial belt–pole distribution, respectively. (3) Over the past two decades, the economic development of these three urban agglomerations has progressed towards the pattern of regional coordinated development, pole-driven development and urban–rural integrated development. The research results can provide new research perspectives and scientific support for promoting regional balanced development, achieving sustainable development goals, and reducing inequality. Full article

Urban agglomeration (UA) is a highly developed spatial form of urban complex, which is one of the important carriers of regional economic cooperation, international industrial division of labor, and flow of capital and information elements. In China, urban agglomerations (UAs) have become the spatial subject of the national new-type urbanization strategy since the early 21st century and have made irreplaceable contributions to China’s urbanization and economic development. The Guanzhong Plain urban agglomeration (GPUA) is an important economic growth pole in northwest China and a key node in China’s open-door pattern. Exploring the spatial and temporal characteristics and driving factors of its economic development will be an important revelation for the promotion of high-quality economic development of the GPUA. This paper characterizes the level of economic development of GPUA with a long series of nighttime light data between 2002 and 2022. The standard deviation ellipse, spatial autocorrelation analysis, the economic difference index, and grey correlation analysis are used to analyze the characteristics of spatio-temporal evolution, internal diversity, and driving factors of economic development of the GPUA. The results show that the economic development level of the GPUA continued to increase from 2002 to 2022. The spatial distribution of the GPUA economy is “northeast-southwest” axial distribution, and the center of gravity of economic development gradually moves westward. The differences in the level of economic development within the GPUA show a typical core–periphery structure, but the degree of difference tends to weaken over time. The internal expansion force and economic promotion force were the dominant factors for the economic development of the GPUA in the early years. However, with the passage of time, scientific and technological support and government support have gradually become the main influencing factors for the economic development of the GPUA nowadays. Full article