bluuebunny/crossref_metadata_2025 huggingface dataset:
Multi-Scenario Simulation and Driving Force Analysis of Ecosystem Service Value in Arid Areas Based on PLUS Model: A Case Study of Jiuquan City, China
Authors: Shi Jing , Shi Peiji , Wang Ziyang , Wang Lirong , Li Yali
Published: April 2023

The arid region of northwest China is an extremely fragile area of natural ecology. With population growth and continuous expansion of urban scale, the ecosystem in the arid region is facing greater pressure. Scientific assessment and prediction of the value of ecosystem services in arid areas are necessary and of great significance for the sustainable development of regional ecological environments. In this paper, a parametric optimal geographic model is used to analyze the driving factors of ESV spatial dispersion in Jiuquan City as an example. The PLUS model is also used to simulate the spatial and temporal evolution of ESV in 2035 under the scenarios of natural development, urban development, water constraints and ecological conservation, based on the historical change pattern of land use and ecosystem service value (ESV). The results showed that from 1980 to 2020, the plowland, water and construction land area in Jiuquan City showed a significant increasing trend, while other land use types showed a decreasing trend. ESV has increased from CNY 139.394 billion to CNY 142.642 billion. The expansion of plowland and water area was the main reason for the increase in ESV. Elevation, temperature, and precipitation are the main driving factors of spatial differentiation of ESV in Jiuquan City. The interaction of natural and human factors enhances the explanatory power of each factor to the spatial differentiation of ESV. In 2035, the ESV in four development scenarios in Jiuquan City showed an upward trend, and the ESV of the ecological protection scenario was the highest, which was the best mode to realize a sustainable development in Jiuquan City in the future. This study can provide scientific basis and decision-making basis for Jiuquan City to formulate sustainable development strategy.
The Impact of Bancassurance Interaction on the Adoption Behavior of Green Production Technology in Family Farms: Evidence from China
Authors: Wang Linwei , Hu Yixin , Kong Rong
Published: April 2023

In the context of increasingly severe resource and environmental constraints, accelerating family farms to take the path of green agricultural development is an urgent practical problem to be solved. The bancassurance interaction, an innovative form of financial support policy for agriculture, can effectively alleviate the risks and credit rationing problems faced by family farms in the operation process, provide new opportunities for green production of family farms, and is of great significance to promoting sustainable agricultural development. This study uses data from 564 planting family farms in Shaanxi Province to analyze the impact of the bancassurance interaction on adopting green production technology in family farms and its mechanism, paying particular attention to the heterogeneous effects of the family life cycle and family economic level. The results of this study show that the bancassurance interaction has a significant positive impact on the adoption of green production technology by family farms. Compared with agricultural credit and insurance, the effect of the bancassurance interaction on adopting green production technologies is more evident. The analysis of the impact mechanism shows that the bancassurance interaction can promote the adoption of green production technology in family farms through three channels: increasing investment in agricultural production, expanding the scale of land management, and strengthening exchanges of green technology. Among them, the effect of increasing agrarian production investment is the most pronounced. The heterogeneity analysis shows that the impact of the bancassurance interaction on the green production technology of family farms varies significantly according to the family life cycle and economic level. Family farms at the dependency stage and low-income level were more willing to adopt green production technologies driven by the bancassurance interaction. Therefore, it is necessary to continuously innovate the interaction mode between banks and insurance companies, rationally allocating agricultural production factors and combining the actual situation of each family farm to strengthen the leading role of the bancassurance interaction in adopting green production technologies and promoting high-quality agricultural development.
Measurement and Development of Park Green Space Supply and Demand Based on Community Units: The Example of Beijing’s Daxing New Town
Authors: Zheng Zhuo , Zhang Zihan , Wang Siyuan
Published: April 2023

In urban development, balancing the ecological services of park green space with residents’ daily life and recreational needs, achieving sustainable development is an important issue in urban construction. The satellite cities of megacities have large development potential and are suitable research objects. This paper takes the Daxing District of Beijing as the research target and measures the integrated level of supply and demand by selecting unique evaluation indicators by integrating various dimensions and using the improved coupled coordination model and indicators with an expanded selection range at the smallest administrative unit of Chinese community unit scale innovatively. The study shows that: (1) The spatial heterogeneity between the supply and demand of parkland in 85 community units in Daxing New Town is obvious, the overall performance conforms with “demand exceeds supply”, and the supply and demand are generally positively correlated. (2) The correlation degree of the matched supply and demand is analyzed, and it is found that 55 community units show a mismatch between supply and demand and 53 community units have a low level of coordinated development. (3) The superposition analysis shows that the comprehensive level of supply and demand decreases from north to south and from the center to the surrounding area. (4) According to the Daxing New City Park Green Space Coupling Coordination Relationship and Policy Document, we divided the community units in Daxing New Town into six types, and provided differentiated development suggestions. The results of the study can help to guide the sustainable construction of Daxing New City and provide a basis for the future construction of satellite cities in other megacities.
Walkability under Climate Pressure: Application to Three UNESCO World Heritage Cities in Central Spain
Authors: Velázquez Javier , Infante Javier , Gómez Inmaculada , Hernando Ana , Gülçin Derya , Herráez Fernando , Rincón Víctor , Castanho Rui Alexandre
Published: April 2023

Walkability is a modern concept that has become important in recent years due to the doubtless effects it has on aspects such as health and wellbeing, sustainable development, climate change, and tourism. It is necessary, therefore, that urban development strategies aim to achieve walkable cities. The main objective of this study is to define a methodology to calculate the walkability index in tourist cities and to predict the effects of climate change on this index, which is applied to three World Heritage cities in central Spain: Salamanca, Ávila, and Segovia. The methodology is developed in three phases. Phase I focus on the calculation of walkability, considering the following factors: facilities and services, accessibility, sidewalk width, population density, green areas, and urban trees. In Phase II, walkability in 2020, climate-related variables were added to the previous result: temperatures, solar radiation, and shadows. Finally, the third phase, walkability under climate change pressure in 2030, 2050, and 2100, establish predictions for different climate scenarios. The results show excellent walkability indices (higher) in city centers and newly built neighborhoods and low values in the rest of the peripheral areas, industrial estates, and neighborhoods. Climate predictions showed a generalized decrease in walkability over time, even higher in the scenario with high greenhouse gas emissions. Likewise, the models can be an excellent tool for the tourist management of cities since they show the most walkable areas and, therefore, the most suitable for tourist routes.
Temporal and Spatial Effects of Heavy Metal-Contaminated Cultivated Land Treatment on Agricultural Development Resilience
Authors: Chen Danling , Hu Wenbo
Published: April 2023

Heavy metal-contaminated cultivated land treatment (HMCLT) plays an essential role in the realization of sustainable utilization of cultivated land resources and sustainable agricultural development. Evaluating this policy’s impact on agricultural development resilience (ADR) has great practical significance. This paper reveals the impact HMCLT has on ADR from the perspectives of time and space, utilizing data from Hunan province between 2007 and 2019. The synthetic control method (SCM) and spatial Durbin model (SDM) are employed for investigating the temporal and spatial effects HMCLT has on ADR. The results demonstrate that the HMCLT policy has effectively improved the pilot cities’ ADR and can enhance ADR in adjacent areas from a spatial perspective. In addition to HMCLT policy, financial support for agriculture, farmers’ per capita disposable income, and rural population density are key factors affecting ADR. However, they all have a crowding-out effect on the ADR in neighboring areas. Due to these circumstances, while the governments make efforts in promoting the policy design and improvement of HMCLT, increasing the disposable income of farmers, narrowing regional differences in government financial support and human capital, and promoting regional interactions are essential to enhance ADR. This study formulates valuable insights for policymakers and researchers in the field of sustainable agricultural development.
Spatial Optimization of Park Green Spaces by an Improved Two-Step Optimization Model from the Perspective of Maximizing Accessibility Equity
Authors: Mu Lei , Xing Lijun , Jing Ying , Hu Qinjiang
Published: April 2023

As a type of public land, park green spaces (PGSs) carry the daily recreation and social communication of urban residents, and the inequity of their space accessibility has been widely confirmed. However, the optimized suggestions based on evaluations of accessibility and equity in previous studies cannot guide actual planning effectively because the reasonable locations and scales of construction of PGSs were difficult to accurately identify. This study first constructed two equity objective functions: the minimum standard deviation (SD) and the minimum Gini coefficient (GC) in accessibility; then an improved two-step optimization method considering location-allocation was adopted to maximal accessibility equity (MAE) for optimizing the spatial layout of PGSs and doing comparisons of these two objectives for further analysis. The results showed that the improved method based on covering the accessibility blind area and preserving the existing PGSs could optimize the location selection and rationally determine the area. The two objective functions were both effective for optimization, but the GC minimization is more advantageous than the SD for achieving the MAE. The accessibility value increased significantly in a higher proportion of regions, and the overall accessibility median increased by 0.0445. It is worth mentioning that the MAE optimization would lead to a new imbalance between supply and demand in some regions. This indicated that the strictly restricted area standard may lead to the oversupply of PGSs in some areas, while the improvement of equity might not mean the improvement of accessibility. The proposed optimization framework could achieve the optimal layout of PGSs on the goal of MAE. Our findings also could provide inspiration for the equity allocation of other types of public facility lands and support decision-making for government departments regarding management and planning.
The Persistent, Pernicious Use of Pushbacks against Children and Adults in Search of Safety
Authors: Bochenek Michael Garcia
Published: April 2023

Border pushbacks, including at the European Union’s external borders and by countries such as Australia, Mexico, Turkey, and the United States, are common—and in fact have become a new normal. These border policing or other operations aim to prevent people from reaching, entering, or remaining in a territory. Screening for protection needs is summary or non-existent. Pushbacks violate the international prohibitions of collective expulsion and refoulement, and pushbacks of children are inconsistent with the best interests principle and other children’s rights standards. Excessive force, other ill-treatment, family separation, and other rights violations may also accompany pushback operations. Despite formidable obstacles such as weak oversight mechanisms, undue judicial deference to the executive, and official ambivalence, domestic court rulings and other initiatives show some promise in securing compliance with international standards and affording a measure of accountability.
Evaluation of Different SNP Analysis Software and Optimal Mining Process in Tree Species
Authors: Bu Mengjia , Xu Mengxuan , Tao Shentong , Cui Peng , He Bing
Published: April 2023

Single nucleotide polymorphism (SNP) is one of the most widely used molecular markers to help researchers understand the relationship between phenotypes and genotypes. SNP calling mainly consists of two steps, including read alignment and locus identification based on statistical models, and various software have been developed and applied in this issue. Meanwhile, in our study, very low agreement (<25%) was found among the prediction results generated by different software, which was much less consistent than expected. In order to obtain the optimal protocol of SNP mining in tree species, the algorithm principles of different alignment and SNP mining software were discussed in detail. And the prediction results were further validated based on in silico and experimental methods. In addition, hundreds of validated SNPs were provided along with some practical suggestions on program selection and accuracy improvement were provided, and we wish that these results could lay the foundation for the subsequent analysis of SNP mining.
Substance P Alleviates Retinal Pigment Epithelium Dysfunction Caused by High Glucose-Induced Stress
Authors: Lee Dahyeon , Hong Hyun Sook
Published: April 2023

When the retina is constantly affected by high glucose (HG) due to diabetes, the barrier function of the retinal pigment epithelium (RPE) is impaired, accompanied by unnecessary vascularization. This eventually leads to the development of diabetic retinopathy (DR). This study investigated the recovery effect of substance P (SP) on RPE injured by HG. RPE was treated with HG for 24 h, and HG-induced cellular injuries were confirmed. SP was added to the dysfunctional RPE. Compared to RPE in low glucose (LG) conditions, HG-damaged RPE had large, fibrotic cell shapes, and its cellular viability decreased. HG treatment reduced tight junction protein expression levels and caused oxidative stress by interrupting the antioxidant system; this was followed by inflammatory factor intracellular adhesion molecule-1 (ICAM-1), Monocyte chemotactic protein-1 (MCP-1), and angiogenesis factor vascular endothelial growth factor (VEGF) expression. SP treatment contributed to RPE recovery by enhancing cell viability, tight junction protein expression, and RPE function under HG conditions, possibly by activating the Akt signaling pathway. Importantly, SP treatment reduced ICAM-1, MCP-1, and VEGF expression. Collectively, SP activated survival signals to suppress oxidative stress and improve retinal barrier function in RPE, accompanied by immune suppression. This suggests the possible application of SP to diabetic retinal injuries.
The Effects of Humic Acids on the Early Developmental Stages of African Cichlids during Artificial Breeding
Authors: Ondrašovičová Silvia , Zigo František , Gogoľa Július , Lacková Zuzana , Farkašová Zuzana , Arvaiová Juliana , Almášiová Viera , Rehan Ibrahim F.
Published: April 2023

The aim of this study was to compare the effect of humic acid (HA) obtained by extraction from alginate on the incubation of roes and fry development in African cichlids, Labidochormis caeruleus, as well as their influence on the stabilization of the physicochemical parameters of water in an aquarium during artificial breeding. The roes were obtained by extruding from a female buccal cavity immediately after fertilization. For the experiment, 4 groups of 40 roes were formed in an incubator with an artificial hatchery. Groups 1–3 were exposed to 1%, 5%, and 10% concentrations of HA, respectively. The control group C was not exposed to HA. In all groups, the mortality and size differences of the fry, as well as the temperature, pH, hardness, nitrite, and nitrate levels in the tanks, were determined during a 30-day monitoring period until the resorption of the yolk sac. The results of this study indicated the ability of HA in 5% and 10% concentrations to reduce nitrite and nitrate levels in the aquatic environment, which significantly reduced the mortality of roes and the survivability of the fry. The determination of the morphological measurements of the fry revealed an increased body length in the groups exposed to 5% and 10% HA concentrations compared to the control group by the end of the monitored period. It was also noted that the yolk sac was resorbed two days earlier in the same groups than in the control. Thus, the results showed that HAs are suitable for use in the artificial aquarium incubation of roes and fry development, which are increasingly exposed to adverse environmental factors. The knowledge obtained in this study and its transfer into practice can allow even less experienced aquarists to successfully breed aquarium fish species that could not normally be bred under artificial conditions without the addition of HA.
Efficacy and Safety of Neoadjuvant Luteinizing Hormone-Releasing Hormone Antagonist and Tegafur-Uracil Chemohormonal Therapy for High-Risk Prostate Cancer
Authors: Sugino Fumiya , Nakane Keita , Kawase Makoto , Ueda Shota , Tomioka Masayuki , Takeuchi Yasumichi , Tomioka-Inagawa Risa , Yamada Toyohiro , Namiki Sanae , Kumada Naotaka , Takeuchi Shinichi , Kawase Kota , Kato Daiki , Takai Manabu , Iinuma Koji , Tobisawa Yuki , Koie Takuya
Published: April 2023

Background: This retrospective single-center cohort study evaluated the efficacy and safety of a combination of neoadjuvant luteinizing hormone-releasing hormone (LHRH) antagonist and tegafur-uracil (UFT) therapy (NCHT) and investigated the medical records of patients with high-risk PCa who underwent robot-assisted radical prostatectomy (RARP). The therapy was followed by RARP for high-risk PCa. Materials and Methods: The enrolled patients were divided into two groups: low-intermediate-risk PCa patients who underwent RARP without neoadjuvant therapy (non-high-risk) and those who underwent NCHT followed by RARP (high-risk group). This study enrolled 227 patients (126: non-high-risk and 101: high-risk group). Patients in the high-risk-group had high-grade cancer compared to those in the non-high-risk-group. Results: At the median follow-up period of 12.0 months, there were no PCa deaths; two patients (0.9%) died of other causes. Twenty patients developed biochemical recurrence (BCR); the median time until BCR was 9.9 months after surgery. The 2-year biochemical recurrence-free survival rates were 94.2% and 91.1% in the non-high-risk and high-risk-group, respectively (p = 0.465). Grade ≥3 NCHT-related adverse events developed in nine patients (8.9%). Conclusions: This study indicates that combining neoadjuvant LHRH antagonists and UFT followed by RARP may improve oncological outcomes in patients with high-risk PCa.
Modern Trends in Natural Antibiotic Discovery
Authors: Baranova Anna A. , Alferova Vera A. , Korshun Vladimir A. , Tyurin Anton P.
Published: April 2023

Natural scaffolds remain an important basis for drug development. Therefore, approaches to natural bioactive compound discovery attract significant attention. In this account, we summarize modern and emerging trends in the screening and identification of natural antibiotics. The methods are divided into three large groups: approaches based on microbiology, chemistry, and molecular biology. The scientific potential of the methods is illustrated with the most prominent and recent results.
Spring of Warta River as a Source of Antibiotic-Resistant Coliform Bacteria
Authors: Koczura Ryszard , Pierzchlewicz Joanna , Mokracka Joanna
Published: April 2023

The aim of the study was to evaluate the occurrence of integron-carrying coliform bacteria in the spring water of Warta river, a major river in Poland. We isolated 18 strains (12 Escherichia coli, three Pantoea sp., 2 Citrobacter freundii, and 1 Klebsiella oxytoca) harbouring class 1 and/or class 2 integrons. Class 1 integrons contained aadA1, dfrA7, dfrA17, dfrA1-aadA1, and dfrA17-aadA5 gene cassette arrays, whereas the genetic content of class 2 integrons was stable and consisted of sat2-aad1 gene cassette array. The strains carrying integrons were resistant to 4–11 antimicrobials, most frequently to sulfamethoxazole, ampicillin, piperacillin, trimethoprim, and trimethoprim/sulfamethoxazole.
A Review of In-Situ TEM Studies on the Mechanical and Tribological Behaviors of Carbon-Based Materials
Authors: Hu Zelong , Fan Xue , Diao Dongfeng
Published: April 2023

Carbon-based materials are widely applied in various devices due to their outstanding mechanical and tribological behaviors. In recent years, more attention has been paid to clarifying the nanocontact mechanisms of carbon-based materials, in order to promote nanoscale applications. The in-situ TEM method is currently the only way that can combine contact behavior and real interface. However, there is still a lack of a systematic summary of in-situ TEM studies on carbon-based materials. Therefore, this work provides an overview of in-situ TEM mechanical and tribological studies on carbon-based materials, consisting of the quantitative actuation and detection for in-situ tests, the strength of fracture and yield, the adhesion between interfaces, the friction performance, and wear features of carbon-based materials with different nanostructures, such as carbon nanotube, graphene, graphite, amorphous, sp2 nanocrystalline, and ultrananocrystalline diamond. Nanostructures play a crucial role in determining mechanical and tribological behaviors. Perspectives on current challenges and future directions are presented, with the aim of promoting the advancement of in-situ TEM research.
Synthesis of 2-(5-(2-Aminopropyl)-2-hydroxyphenyl)acetic Acid, a Metabolite of the Drug 5-APB
Authors: Silva André L. , Fino Inês , Ferreira Luísa M. , Branco Paula S.
Published: April 2023

5-(2-Aminopropyl)benzofuran (5-APB), also known as “Benzo Fury,” is a novel psychoactive substance (NPS) belonging to a new class of synthetic phenethylamines. It acts by disrupting serotonergic circuits as a serotonin–norepinephrine–dopamine reuptake inhibitor and is classified as an entactogen, similar to MDMA and MDA. Despite its popularity among users, recent toxicity events have been associated with the consumption of 5-APB and other benzofurans, highlighting the need for a better understanding of their pharmacodynamics and toxicity. One way to achieve this is by developing the synthesis of 5-APB metabolites as biomarkers of exposure. In this study, we present a six-step synthesis for one of the 5-APB metabolites, 2-(5-(2-aminopropyl)-2-hydroxyphenyl)acetic acid (1), involving methylation, formylation, Aldol-type condensation, reduction, and hydrolysis reactions. The compound was obtained in an overall yield of 11%.
Effect of Air Velocity and Initial Conditioning on the Moisture Buffer Value of Four Different Building Materials
Authors: Khaled Sana , Collet Florence , Prétot Sylvie , Bart Marjorie
Published: April 2023

Porous materials are able to exchange moisture with the surrounding air. The more hygroscopic they are, the more they contribute to regulate ambient humidity. This ability is characterized by the moisture buffer value (MBV) which is measured under dynamic solicitations according to different protocols. The NORDTEST protocol is the most commonly-used. It gives recommendations regarding the air velocity and the ambient conditions for initial stabilization. The purpose of this article is to measure the MBV according to the NORDTEST protocol and to study the effect of air velocity and of initial conditioning on the MBV results for different materials. Two mineral and two bio-based materials are considered: gypsum (GY), cellular concrete (CC), thermo-hemp (TH) and fine-hemp (FH). Following the NORDTEST classification, GY is a moderate hygric regulator, CC is good, TH and FH are excellent. When the air velocity ranges from 0.1 to 2.6 m/s, the MBV of GY and CC materials remains constant, but the MBV of TH and FH materials is highly affected. The initial conditioning has no effect on the MBV, but has an effect on the water content of the material, whatever the material.
Energy Storage and Dissipation in Consecutive Tensile Load-Unload Cycles of Gum Metal
Authors: Golasiński Karol Marek , Staszczak Maria , Pieczyska Elżbieta Alicja
Published: April 2023

Multifunctional β-titanium alloy Gum Metal, characterized by a relatively low elastic modulus, superelastic-like behavior and high strength, was subjected to cyclic tensile loadings. The characteristics of macroscopic scale energy storage and dissipation in the consecutive loading–unloading cycles were studied. Various kinds of energy components related to the alloy deformation process were determined experimentally and analyzed using thermodynamic relations. The values of the entire work needed to deform the alloy Wext, the work used for recoverable deformation Wrec consisting of the elastic deformation energy Wel , the superelastic-like energy Wpt , and the energy of thermoelastic effect Eth , were derived from the Gum Metal stress and temperature vs. strain curves. The irrecoverable mechanical energy Wir expended on plastic deformation, the dissipation energy Q, and finally the stored energy Es  were estimated. The stored energy represents a change in the internal energy of the deformed material and is an essential measure of cold-worked state. The Es value turned out to be not large for the Gum Metal, which confirms the alloy low hardening property. The energy components determined for each of the 24 loading cycles enabled us to analyze various stages of the Gum Metal deformation process, including necking and damage.
Artifact-Free Microstructures in the Interfacial Reaction between Eutectic In-48Sn and Cu Using Ion Milling
Authors: Chang Fu-Ling , Lin Yu-Hsin , Hung Han-Tang , Kao Chen-Wei , Kao C. R.
Published: April 2023

Eutectic In-48Sn was considered a promising candidate for low-temperature solder due to its low melting point and excellent mechanical properties. Both Cu2(In,Sn) and Cu(In,Sn)2 formation were observed at the In-48Sn/Cu interface after 160 °C soldering. However, traditional mechanical polishing produces many defects at the In-48Sn/Cu interface, which may affect the accuracy of interfacial reaction investigations. In this study, cryogenic broad Ar+ beam ion milling was used to investigate the interfacial reaction between In-48Sn and Cu during soldering. The phase Cu6(Sn,In)5 was confirmed as the only intermetallic compound formed during 150 °C soldering, while Cu(In,Sn)2 formation was proven to be caused by room-temperature aging after soldering. Both the Cu6(Sn,In)5 and Cu(In,Sn)2 phases were confirmed by EPMA quantitative analysis and TEM selected area electron diffraction. The microstructure evolution and growth mechanism of Cu6(Sn,In)5 during soldering were proposed. In addition, the Young’s modulus and hardness of Cu6(Sn,In)5 were determined to be 119.04 ± 3.94 GPa and 6.28 ± 0.13 GPa, respectively, suggesting that the doping of In in Cu6(Sn,In)5 has almost no effect on Young’s modulus and hardness.
Inversion of the Complex Refractive Index of Au-Ag Alloy Nanospheres Based on the Contour Intersection Method
Authors: Cheng Long , Tuersun Paerhatijiang , Ma Dengpan , Wumaier Dilishati , Li Yixuan
Published: April 2023

The contour intersection method is a new method used to invert the complex refractive index of small particles. Research has yet to be reported on using this method to invert the complex refractive index of nanoparticles. This paper reports the feasibility and reliability of the contour intersection method in the inversion of the complex refractive index of nanoparticles using Au-Ag alloy nanospheres. The Mie theory and the size-dependent dielectric function are used to calculate the light scattering and absorption efficiency of Au-Ag alloy nanospheres corresponding to the complex refractive index. The complex refractive index of the particles is obtained by inversion with the contour intersection method. The backscattering efficiency constraint method is used to determine the unique solution when multiple valid solutions from the contour intersection method appear. The effects of the Au component percentage, particle size, and measurement errors on the inversion results are quantitatively analyzed. Finally, the inversion accuracy is compared and analyzed with the traditional iterative method. The results show that as long as the light scattering efficiency, light absorption efficiency, and backscattering efficiency of Au nanospheres can be measured, the accurate complex refractive index can also be calculated by inversion using the contour intersection method. The accuracy of the inversion results can be ensured when the measurement error is less than 5%. The results of inversion using the contour intersection method are better than those of the iterative methods under the same conditions. This study provides a simple and reliable inversion method for measuring the complex refractive index of Au-Ag alloy nanospheres.
Biomechanical Effects of the Porous Structure of Gyroid and Voronoi Hip Implants: A Finite Element Analysis Using an Experimentally Validated Model
Authors: Salaha Zatul Faqihah Mohd , Ammarullah Muhammad Imam , Abdullah Nik Nur Ain Azrin , Aziz Aishah Umairah Abd , Gan Hong-Seng , Abdullah Abdul Halim , Abdul Kadir Mohammed Rafiq , Ramlee Muhammad Hanif
Published: April 2023

Total hip arthroplasty (THA) is most likely one of the most successful surgical procedures in medicine. It is estimated that three in four patients live beyond the first post-operative year, so appropriate surgery is needed to alleviate an otherwise long-standing suboptimal functional level. However, research has shown that during a complete THA procedure, a solid hip implant inserted in the femur can damage the main arterial supply of the cortex and damage the medullary space, leading to cortical bone resorption. Therefore, this study aimed to design a porous hip implant with a focus on providing more space for better osteointegration, improving the medullary revascularisation and blood circulation of patients. Based on a review of the literature, a lightweight implant design was developed by applying topology optimisation and changing the materials of the implant. Gyroid and Voronoi lattice structures and a solid hip implant (as a control) were designed. In total, three designs of hip implants were constructed by using SolidWorks and nTopology software version 2.31. Point loads were applied at the x, y and z-axis to imitate the stance phase condition. The forces represented were x = 320 N, y = −170 N, and z = −2850 N. The materials that were used in this study were titanium alloys. All of the designs were then simulated by using Marc Mentat software version 2020 (MSC Software Corporation, Munich, Germany) via a finite element method. Analysis of the study on topology optimisation demonstrated that the Voronoi lattice structure yielded the lowest von Mises stress and displacement values, at 313.96 MPa and 1.50 mm, respectively, with titanium alloys as the materials. The results also indicate that porous hip implants have the potential to be implemented for hip implant replacement, whereby the mechanical integrity is still preserved. This result will not only help orthopaedic surgeons to justify the design choices, but could also provide new insights for future studies in biomechanics.
Comparative Verification of the Accuracy of Implant Models Made of PLA, Resin, and Silicone
Authors: Wakamori Kana , Nagata Koudai , Nakashizu Toshifumi , Tsuruoka Hayato , Atsumi Mihoko , Kawana Hiromasa
Published: April 2023

Polylactic acid (PLA) has gained considerable attention as an alternative to petroleum-based materials due to environmental concerns. We fabricated implant models with fused filament fabrication (FFF) 3D printers using PLA, and the accuracies of these PLA models were compared with those of plaster models made from silicone impressions and resin models made with digital light processing (DLP). A base model was obtained from an impact-training model. The scan body was mounted on the plaster, resin, and PLA models obtained from the base model, and the obtained information was converted to stereolithography (STL) data by the 3D scanner. The base model was then used as a reference, and its data were superimposed onto the STL data of each model using Geomagic control. The horizontal and vertical accuracies of PLA models, as calculated using the Tukey–Kramer method, were 97.2 ± 48.4 and 115.5 ± 15.1 μm, respectively, which suggests that the PLA model is the least accurate among the three models. In both cases, significant differences were found between PLA and gypsum and between the PLA and resin models. However, considering that the misfit of screw-retained implant frames should be ≤150 µm, PLA can be effectively used for fabricating implant models.
Catalytic Properties of Two Complexes of chromium(III) and cobalt(II) with Nitrilotriacetate, Dipicolinate, and 4-Acetylpyridine
Authors: Malinowski Jacek , Drzeżdżon Joanna , Jarzembska Katarzyna N. , Kamiński Radosław , Rybiński Przemysław , Gawdzik Barbara , Jacewicz Dagmara
Published: April 2023

In this paper, a synthesis of two innovative coordination compounds, based on chromium(III) and cobalt(II) ions with N,O-donor ligands (nitrilotriacetate, dipicolinate) and 4-acetylpyridine, is reported. The obtained metal-organic compounds were structurally characterized using the single-crystal X-ray diffraction (XRD) method. The well-defined chromium(III) and cobalt(II) complexes were used as precatalysts in the oligomerization reaction of 2-chloro-2-propen-1-ol and 2-propen-1-ol with methylaluminoxane (MMAO) as an activator. The products of the oligomerization reaction were subjected to full physicochemical characteristics, i.e., time-of-flight mass spectrometry (MALDI-TOF-MS), TGA, and differential scanning calorimetry (DSC) methods. The catalytic activity of the precatalysts in both reactions was calculated and compared with other catalysts known in the literature.
An Analytical Method for Elastic Modulus of the Sandwich BCC Lattice Structure Based on Assumption of Linear Distribution
Authors: Shang Jinqi , Wang Kangkang , Yan Dongyang , Liu Fengrui , Wang Linjuan , Zhao Libin
Published: April 2023

An analytical method to predict the elastic modulus of the sandwich body-centered cubic (BCC) lattice structure is presented on the basis of the assumption of a linearly changing elastic modulus. In the constrained region, the maximum of elastic modulus used the elastic moduli of the BCC lattice element with plate constraints and is calculated with Timoshenko beam theory, the minimum used without plate constraints. In the rest of the constrained region, a linear function along the thickness direction is proposed to calculate elastic modulus. The elastic modulus of the unconstrained region is constant and it is the same as the minimum of the constrained region. The elastic modulus of the whole sandwich BCC lattice structure can be calculated theoretically with the elastic modulus of the constrained and unconstrained regions and a single-layer slice integration method. Six kinds of sandwich BCC lattice structures with different geometric parameters are designed and made by resin 3D printing technology, and the elastic moduli are measured. By comparing the predictions of the elastic modulus using the proposed analytical method and existing method with experimental results, the errors between the results of the existing method and the experimental results varied from 10.3% to 24.7%, and the errors between the results of the proposed method and the experimental results varied from 1.6% to 7.4%, proving that the proposed method is more accurate than the existing methods.
Torsional Vibrations in the Resonance of High-Speed Rotor Bearings Reduced by Dynamic Properties of Carbon Fiber Polymer Composites
Authors: Murčinková Zuzana , Živčák Jozef , Sabol Dominik
Published: April 2023

The present study deals with the harmful torsional resonance vibrations of textile rotor bearings, the amplitudes of which are reduced mainly by the use of high-capacity damping materials, characterized by an internal hierarchical structure and macroshape, added into the machine mechanical system. The additional materials are polymer matrix composites reinforced either by carbon nanofibers or carbon chopped microfibers and either aramid or carbon continuous fibers. The macroshape is based on a honeycomb with internal cavities. Torsional vibrations arise in mechanical systems as a result of fluctuations in the low-level pressing load of the flat belt driving the rotor-bearing pin and the changing of kinematic conditions within it, which, in the resonance area, leads to cage slip and unwanted impulsive torsional vibrations. Moreover, this occurs during high-frequency performance at around 2100 Hz, i.e., 126,000 min−1. The condition, before the redesign, was characterized by significantly reduced textile rotor-bearing life due to significant impulse torsional vibrations in the resonance area. The study showed a significant reduction in average and maximum torsional amplitudes in the resonance area by 33% and 43%, respectively. Furthermore, the paper provides visualization of the propagation of a stress wave at the microscale obtained by the explicit finite element method to show the dispersion of the wave and the fibers as one of the sources of high damping.
Performance Analysis of Loose-Fill Thermal Insulation from Wood Scobs Coated with Liquid Glass, Tung Oil, and Expandable Graphite Mixture
Authors: Augaitis Nerijus , Šeputytė-Jucikė Jurga , Członka Sylwia , Kremensas Arūnas , Kairytė Agnė , Vėjelis Sigitas , Balčiūnas Giedrius , Vaitkus Saulius
Published: April 2023

The current study presents the results of monitoring the behavior of loose-fill thermal insulating material for buildings made of wood scobs (WS), which were coated with one, two, and three component-based coatings from liquid glass (LG), tung oil (TO), and expandable graphite (EG). The thermal conductivity of samples in the dry state and under normal laboratory conditions, short-term water absorption by partial immersion, surface wettability, and water vapor permeability were evaluated, and regression equations describing the variations in numerical values of specified properties under different amounts of each coating component were presented. It was shown that LG and TO act as hydrophobic layers that, in conjunction, reduce water absorption by a maximum of 274%, have a contact angle equal to 86°, and lower thermal conductivity by 55% in the dry state due to the specifics of the layer formed on the surface of WS. The addition of EG to LG coating resulted in insignificantly changed water absorption and thermal conductivity values, indicating the potential of this material to be used to improve the fire resistance of wood-based composites in the future. The results showed that the three-component layer of LG/TO/EG reduces water absorption by a maximum of 72%, increases thermal conductivity in the dry state by a minimum of 0.4%, and increases the contact angle to 81° at 100 wt.% LG. The changes in water vapor permeability of all compositions were determined to be insignificant.
Fatigue Properties of Spring Steels after Advanced Processing
Authors: Procházka Radek , Stehlík Adam , Kotous Jakub , Salvetr Pavel , Bucki Tomasz , Stránský Ondřej , Zulić Sanin
Published: April 2023

This article deals with the effect of strain-assisted tempering (SAT) on the fatigue properties of 54SiCr6 steel used for spring steel wires in a wide variety of automotive applications, including coil springs. This steel spring wire is extremely strong, having a high elastic limit and yield point, giving the steel excellent energy accumulation and fatigue properties. This combination opens up new possibilities in helical and cylindrical coil spring design, resulting in the reduction of both size and weight. Lightweight coil springs lead to improvements in fuel consumption, stability and vehicle traction. A large plastic deformation and SAT were applied to enhance the yield point of the study material. Improvements in the static and cyclic properties of steel springs were investigated using tensile tests and 3PB fatigue tests at ambient temperature. In addition, an advanced laser shock peening (LSP) process was employed to increase the fatigue resistance of the SAT material. The results presented here show great improvements in the static and fatigue properties over commercial steel treatment. The material quality of the wires was evaluated to be insufficient for further processing with cold coiling.
Modeling the Crack Interference in X80 Oil and Gas Pipeline Weld
Authors: Cui Wei , Xiao Zhongmin , Zhang Qiang , Yang Jie , Feng Ziming
Published: April 2023

Based on the numerical simulation method of the virtual crack closure technique (VCCT), an interference model was established to investigate the physical problem of two interacting cracks of different sizes in the welding zone of oil and gas pipelines. The obtained results of the current interference problem were compared with those of single crack case. Various crack configurations, such as different crack spacing and different crack sizes, were analyzed. The characteristic quantity fluid pressure load P during the crack propagation process, the peak value of the von Mises stress distribution field of the crack growth path, as well as the difference ∆Bx between the peak value of the magnetic induction intensity component at the crack and the value of the magnetic induction intensity component at its symmetrical position were calculated. The crack interaction scale factors, including γP, γMises, and γΔBx, were compared and analyzed. The numerical modeling results show that when the unequal-length double cracks interfere with each other, the cracks are more likely to propagate toward each other. The tendency of the double-cracks to propagate toward each other gradually weakens as the distance between the crack tips increases and is finally the same as that of single-crack cases. It was also found that the effect of large-sized cracks on small-sized cracks is greater than that of small-sized ones on large-sized ones. The numerical modeling results could be applied for the prediction and analysis of multicrack damage in oil and gas pipeline welds.
Performance and Wear of Diamond Honing Stones
Authors: Mahlfeld Georg , Dröder Klaus
Published: April 2023

Honing is one of the most precise processes for the production of tribologically highly loaded cylindrical bores in different areas of technology. The honing stone specifications influence the process performance to a large extent. During machining, the honing stones are in permanent contact with the workpiece and subject to high mechanical loads. High strength steel and latest coating materials cause additional stress on the honing stones and induce increased wear. The objective is to determine process information for these material properties to support an effective process design. In experiments, the performance and the wear rates of several honing stone specifications were investigated. In this publication, the observed wear mechanisms are analysed and influencing factors for reduced wear are outlined.
The Anatomy of the Internet of Digital Twins: A Symbiosis of Agent and Digital Twin Paradigms Enhancing Resilience (Not Only) in Manufacturing Environments
Authors: Lehmann Joel , Lober Andreas , Häußermann Tim , Rache Alessa , Ollinger Lisa , Baumgärtel Hartwig , Reichwald Julian
Published: April 2023

Due to the growing environmental and geopolitical challenges nowadays, which are causing supply chain complications, industry and society are facing significant new objections. As a complement and extension to the technology-driven premises of Industry 4.0, the value-driven Industry 5.0 focuses on society and the environment. Human centricity, sustainability, and resilience should become a more integral part of both industrial and societal revolutions. One of the enabler technologies for both is the Digital Twin (DT). In order to make DTs intelligent, they must become active, online, goal-seeking, and anticipatory. To meet these requirements, the characteristics of Multi-Agent Systems (MASs) can be employed. This paper contributes to the bilateral emergence of the two industrial paradigms and establishes an approach for the provision of Intelligent Digital Twins (IDTs) within the Internet of Digital Twins (IoDT). Initially, a DT reference model aligned with already established Industry 4.0 reference models enriched with the goals of Industry 5.0 is developed, followed by an outline of how IDTs can be realized with the characteristics of MAS. The work is substantiated by an architectural design for IDTs choreographing marketplace-oriented production processes with a subsequent prototypical implementation, followed by a proof of concept.
Recent Advances on Glyoxylates and Related Structures as Photoinitiators of Polymerization
Authors: Dumur Frédéric
Published: April 2023

The design of photoinitiators activable under low-light intensity is an active research field, supported by the recent energetic sobriety plans imposed by numerous countries in Europe. With an aim to simplify the composition of the photocurable resins, Type I photoinitiators are actively researched as these structures can act as monocomponent systems. In this field, a family of structures has been under-investigated at present, namely, glyoxylates. Besides, the different works carried out in three years have evidenced that glyoxylates and related structures can be versatile for the design of Type I photoinitiators. In this review, an overview of the different glyoxylates and related structures reported to date is provided.