bluuebunny/crossref_metadata_2025 huggingface dataset:
Contemporary Challenges of Regenerative Therapy in Patients with Ischemic and Non-Ischemic Heart Failure
Authors: Banovic Marko , Poglajen Gregor , Vrtovec Bojan , Ristic Arsen
Published: December 2022

It has now been almost 20 years since first clinical trials of stem cell therapy for heart repair were initiated. While initial preclinical data were promising and suggested that stem cells may be able to directly restore a diseased myocardium, this was never unequivocally confirmed in the clinical setting. Clinical trials of cell therapy did show the process to be feasible and safe. However, the clinical benefits of this treatment modality in patients with ischemic and non-ischemic heart failure have not been consistently confirmed. What is more, in the rapidly developing field of stem cell therapy in patients with heart failure, relevant questions regarding clinical trials’ protocol streamlining, optimal patient selection, stem cell type and dose, and the mode of cell delivery remain largely unanswered. Recently, novel approaches to myocardial regeneration, including the use of pluripotent and allogeneic stem cells and cell-free therapeutic approaches, have been proposed. Thus, in this review, we aim to outline current knowledge and highlight contemporary challenges and dilemmas in clinical aspects of stem cell and regenerative therapy in patients with chronic ischemic and non-ischemic heart failure.
BSSRO Improves Mandibular Morphology Mainly through Correction of Body Length and Volume in Patients with Asymmetric Mandibular Prognathism
Authors: Liu Yanfei , Li Yunfeng
Published: December 2022

Purpose: The purpose of this study is to analyze the change and stability of mandibular morphology in patients with asymmetric mandibular prognathism after bilateral sagittal split ramus osteotomy (BSSRO). Methods: We retrospectively analyzed fifty patients with asymmetric mandibular prognathism from the West China Hospital of Stomatology, Sichuan University, between January 2018 to March 2021. The spiral CT data before surgery, within two weeks after surgery, and at more than six months after surgery of each patient were collected. According to the deflection direction of the chin, the bilateral mandibles were defined as the long side and the short side. The morphological data of the bilateral condyle, the mandibular ramus, and the mandibular body were analyzed to determine the effect and stability of BSSRO on asymmetric mandibular prognathism. Results: It was found that the long-side mandible had greater condylar volume and diameter, mandibular ramus height and volume, and mandibular body length and volume (p < 0.05) before surgery. After surgery, the volume of the mandibular ramus increased, while the length and volume of the mandibular body decreased (p < 0.05) at the long side of the mandible; the morphological changes of the mandibular ramus and body at the short side of the mandible were not statistically significant (p > 0.05). When comparing the long and short sides of the mandible, the long side still had greater height and volume of the mandibular ramus (p < 0.01). The volume difference of the mandibular body from the two sides was corrected (p > 0.05), and the length difference of the mandibular body from the two sides was overcorrected (p < 0.05). At more than six months after surgery, the volume of the mandibular ramus and body increased, while their height decreased at the long side of the mandible (p < 0.05). For the other side, or the short side, the volume of the ramus and body increased, too. However, their height decreased (p < 0.01). Conclusion: The results of this study suggested good effect and stability of BSSRO on asymmetric mandibular prognathism, except for the correction of ramus height and volume.
The Intelligent Attitude: What Is Missing from Intelligence Tests
Authors: Sternberg Robert J.
Published: December 2022

Intelligence, like creativity and wisdom, has an attitudinal component as well as an ability-based one. The attitudinal component is at least as important as the ability-based one. Theories of intelligence, in ignoring the attitudinal component of intelligence, have failed to account fully or accurately for why so many people who have relatively high levels of intelligence as an ability fail fully to deploy their ability, especially toward positive ends. The article reviews the need to view intelligence as comprising an attitude as well as an ability, and surveys reasons why people’s lack of an intelligent attitude hinders their deployment of intelligence. Suggestions are made for how things could change in a positive way.
Evidence of Genetic Segregation among Meagre (Argyrosomus regius) Atlantic Spawning Areas
Authors: Almeida Rita , Mateus Catarina S. , Alves Maria Judite , Marques João P. , Pereira Joana , Prista Nuno , Cabral Henrique , Almeida Pedro R. , Quintella Bernardo R.
Published: December 2022

The meagre Argyrosomus regius, one of the largest sciaenidae in the world, is a valuable resource for fisheries and aquaculture. Despite its socioeconomic relevance, knowledge about population dynamics and wild stocks is still scarce, and conservation risks are associated with overexploitation. Two genetic distinct groups, one in the North Atlantic Ocean and one in the eastern Mediterranean Sea, were identified by previous studies. However, little is known about the genetic structure of the Atlantic group, where four important spawning areas have been identified. To assess if each spawning area is an independent breeding unit, the genetic diversity, populational structure, and demographic history of A. regius along the North–East and Eastern Central Atlantic coast were analyzed, using 15 microsatellite loci. Results corroborate the hypothesis tested, suggesting four genetic groups: a first group encompassing individuals from the Gironde spawning area, a second group encompassing individuals from the Tagus spawning area, a third group corresponding to individuals captured in the Algarve region, and a forth group gathering individuals from Morocco and Mauritania. This study reveals the need for specific fisheries management plans considering genetic structure information, and highlights the need for international cooperation.
Finite Time Trajectory Tracking with Full-State Feedback of Underactuated Unmanned Surface Vessel Based on Nonsingular Fast Terminal Sliding Mode
Authors: Xu Donghao , Liu Zipeng , Song Jiuzhen , Zhou Xueqian
Published: December 2022

Marine transportation and operations have attracted the attention of more and more countries and scholars in recent years. A full-state finite time feedback control scheme is designed for the model parameters uncertainty, unknown ocean environment disturbances, and unmeasured system states in the underactuated Unmanned Surface Vessel (USV) trajectory tracking control. The external wind, wave and current environmental disturbances and model parameters perturbation are extended by Nonlinear Extended State Observer (NESO) to the state of the system, namely complex disturbances. The complex disturbances, positions and velocities of USV can be observed by NESO and feedback to USV control system. Next, the underactuated USV error model is obtained by operating the obtained feedback information and the virtual ship model. According to the error model, a Nonsingular Fast Terminal Sliding Model surface (NFTSM) is constructed to realize finite-time control. The control law is deduced through the Lyapunov stability theory to ensure the stability of the system. The results of MATLAB numerical simulations under different disturbances show that the trajectory tracking algorithm has fast responses, and a good convergence of the errors is observed, which verifies the effectiveness of the designed scheme.
Gut Microbial Disruption in Critically Ill Patients with COVID-19-Associated Pulmonary Aspergillosis
Authors: Maurer H. Carlo , Schult David , Koyumdzhieva Plamena , Reitmeier Sandra , Middelhoff Moritz , Rasch Sebastian , List Markus , Janssen Klaus-Peter , Steiger Katja , Protzer Ulrike , Schmid Roland M. , Neuhaus Klaus , Haller Dirk , Quante Michael , Lahmer Tobias
Published: December 2022

Objectives: COVID-19 disease can be exacerbated by Aspergillus superinfection (CAPA). However, the causes of CAPA are not yet fully understood. Recently, alterations in the gut microbiome have been associated with a more complicated and severe disease course in COVID-19 patients, most likely due to immunological mechanisms. The aim of this study was to investigate a potential association between severe CAPA and alterations in the gut and bronchial microbial composition. Methods: We performed 16S rRNA gene amplicon sequencing of stool and bronchial samples from a total of 16 COVID-19 patients with CAPA and 26 patients without CAPA. All patients were admitted to the intensive care unit. Results were carefully tested for potentially confounding influences on the microbiome during hospitalization. Results: We found that late in COVID-19 disease, CAPA patients exhibited a trend towards reduced gut microbial diversity. Furthermore, late-stage patients with CAPA superinfection exhibited an increased abundance of Staphylococcus epidermidis in the gut which was not found in late non-CAPA cases or early in the disease. The analysis of bronchial samples did not yield significant results. Conclusions: This is the first study showing that alterations in the gut microbiome accompany severe CAPA and possibly influence the host’s immunological response. In particular, an increase in Staphylococcus epidermidis in the intestine could be of importance.
Effect of Farnesol in Trichoderma Physiology and in Fungal–Plant Interaction
Authors: Cardoza Rosa E. , McCormick Susan P. , Lindo Laura , Mayo-Prieto Sara , González-Cazón David , Martínez-Reyes Natalia , Carro-Huerga Guzmán , Rodríguez-González Álvaro , Proctor Robert H. , Casquero Pedro A. , Gutiérrez Santiago
Published: December 2022

Farnesol is an isoprenoid intermediate in the mevalonate (MVA) pathway and is produced by the dephosphorylation of farnesyl diphosphate. Farnesol plays a central role in cell growth and differentiation, controls production of ubiquinone and ergosterol, and participates in the regulation of filamentation and biofilm formation. Despite these important functions, studies of farnesol in filamentous fungi are limited, and information on its effects on antifungal and/or biocontrol activity is scarce. In the present article, we identified the Trichoderma harzianum gene dpp1, encoding a diacylglycerol pyrophosphatase that catalyzes production of farnesol from farnesol diphosphate. We analyzed the function of dpp1 to address the importance of farnesol in Trichoderma physiology and ecology. Overexpression of dpp1 in T. harzianum caused an expected increase in farnesol production as well as a marked change in squalene and ergosterol levels, but overexpression did not affect antifungal activity. In interaction with plants, a dpp1-overexpressing transformant acted as a sensitizing agent in that it up-regulated expression of plant defense salicylate-related genes in the presence of a fungal plant pathogen. In addition, toxicity of farnesol on Trichoderma and plants was examined. Finally, a phylogenetic study of dpp1 was performed to understand its evolutionary history as a primary metabolite gene. This article represents a step forward in the acquisition of knowledge on the role of farnesol in fungal physiology and in fungus-environment interactions.
Fungal Host Affects Photosynthesis in a Lichen Holobiont
Authors: Schulz Meike , Schmitt Imke , Weber Daniel , Dal Grande Francesco
Published: December 2022

Corals and lichens are iconic examples of photosynthetic holobionts, i.e., ecological and evolutionary units resulting from the tightly integrated association of algae and prokaryotic microbiota with animal or fungal hosts, respectively. While the role of the coral host in modulating photosynthesis has been clarified to a large extent in coral holobionts, the role of the fungal host in this regard is far less understood. Here, we address this question by taking advantage of the recent discovery of highly specific fungal–algal pairings corresponding to climatically adapted ecotypes of the lichen-forming genus Umbilicaria. Specifically, we compared chlorophyll a fluorescence kinetics among lichen thalli consisting of different fungal–algal combinations. We show that photosynthetic performance in these lichens is not only driven by algal genotype, but also by fungal host species identity and intra-host genotype. These findings shed new light on the closely intertwined physiological processes of fungal and algal partners in the lichen symbiosis. Indeed, the specific combinations of fungal and algal genotypes within a lichen individual—and the resulting combined functional phenotype—can be regarded as a response to the environment. Our findings suggest that characterizing the genetic composition of both eukaryotic partners is an important complimentary step to understand and predict the lichen holobiont’s responses to environmental change.
Utilization of Corn Steep Liquor for the Production of Fairy Chemicals by Lepista sordida Mycelia
Authors: Kobori Hajime , Wu Jing , Takemura Hirohide , Choi Jae-Hoon , Tada Naoto , Kawagishi Hirokazu
Published: December 2022

There are various potential practical uses of fairy chemicals (FCs) in the fields of agriculture, cosmetics, and medicine; however, the production costs of FCs are very high. To enable the practical use of FCs, more efficient and inexpensive methods of culturing the mycelia of FCs-producing fungi and producing FCs need to be developed. The purpose of the present study was to determine methods of reducing the production costs of FCs and mycelia of the FCs-producing fungus Lepista sordida. We investigated the effects of four food industrial by-products, i.e., corn steep liquor (CSL), rice bran, wheat bran, and Japanese liquor lees, as nutritional additives in the liquid culture medium of the fungus. We found that CSL was more effective than the other tested additives in increasing the production of FCs and mycelia. Medium containing 1% CSL was optimal for increasing the mycelial yield while medium containing 6% CSL was optimal for increasing the production of FCs. The reason for this difference in the optimal CSL concentration was considered to be related to the stress on the mycelia caused by the amount of nutrients in the liquid medium. These results are expected to facilitate the practical use of FCs and the mycelia of FCs-producing fungi.
Does the Degree of Mutualism between Epichloë Fungi and Botanophila Flies Depend upon the Reproductive Mode of the Fungi?
Authors: Bultman Thomas L. , Lembicz Marlena , Leuchtmann Adrian
Published: December 2022

Epichloë (Ascomycota: Clavicipitaceae) fungi can form an intriguing interaction with Botanophila flies. The fungi live within above-ground shoots of grasses. Some species (type I) only reproduce sexually by forming stromata on all host culms (choke disease). Stromata produce haploid spores (spermatia) that fertilize stromata of opposite mating type to form dikaryotic cells. A second category of Epichloë species (type II) produces stromata on only some of the host culms; culms without choke produce flowers and seeds. These Epichloë can reproduce asexually by invading host seed, as well as sexually. Female Botanophila flies visit stromata for feeding and oviposition. Spermatia pass through the gut of Botanophila intact and viable. Flies can cross-fertilize the fungus during defecation after egg laying. Hence, we described the interaction as a mutualism similar to pollination. Yet, subsequent work by others and ourselves showed that visitation by Botanophila flies was not necessary for cross fertilization of Epichloë. We believe these contradictory results can be reconciled from an evolutionary perspective, if one takes into account the reproductive mode of the fungus. We explore a novel hypothesis to reconcile this contradiction, its predictions and discuss ways in which to test them.
China’s Media Expansion in Zambia: Influence on Government, Commercial, Community, and Religious Media
Authors: Gondwe Gregory
Published: December 2022

This study examines how news about China is presented, spread and impacts the diversity of opinions in state-owned, commercial, community, and religious media outlets in Zambia. Drawing from the 2012–2021 data, and guided by intermedia agenda-setting theory, we provide evidence of the counter-attitudinal influence of news content on China across the four media categories. While state-owned media emphasized issues of privatization, and government and foreign policies, community and religious media focused on issues of environmental degradation, poor labor conditions, and mining. Commercial media mirrored state-owned media, a trend also reflected in community and religious media outlets across time. These findings suggest that China shapes how the media in Zambia present content about China. As observed, over the years, China is positively presented in the Zambian media.
Correlation between Androgen Receptor Expression in Luminal B (HER–2 Negative) Breast Cancer and Disease Outcomes
Authors: Yang Fan , Li Jiayi , Zhang Hong , Zhang Shuang , Ye Jingming , Cheng Yuanjia , Liu Qian , Xin Ling , Xiang Hongyu , Liu Yinhua , Duan Xuening , Xu Ling
Published: December 2022

(1) Background: Hormone receptor positive breast cancer is a subtype of breast cancer with relatively good prognosis, but luminal B (HER–2 negative) breast cancer has a higher risk of recurrence and metastasis. Patients with endocrine therapy resistance and chemotherapy insensitivity have poor prognosis. Androgen receptor (AR) is widely expressed in breast cancer, but there is no clear conclusion about its function and correlation with prognosis in luminal B breast cancer. Further research is needed to reveal the role of AR in luminal B (HER–2 negative) breast cancer. (2) Methods: Retrospectively analyzed patients with early–stage luminal B breast cancer. The correlation between AR and its associated indexes with long–term survival was determined. (3) Results: A total of 985 patients were included with 143 treated by neoadjuvant therapy. Of these, 83.5% of the patients had AR expression ≥65%. High AR expression was associated with good disease–free survival (DFS) and overall survival (OS). In the neoadjuvant population, AR/estrogen receptor (ER) > 1.06 and residual tumor Ki67 > 23% had significantly worse DFS. (4) Conclusion: Low AR (<65%) expression is associated with poor prognosis in luminal B (HER–2 negative) breast cancer patients. High AR/ER and residual tumor Ki67 were associated with poor DFS in neoadjuvant group with a cutoff value of AR/ER > 1.06 and residual tumor Ki67 > 23%.
Life Quality in Premenopausal Women after Embolization of Uterine Myomas
Authors: Tsikouras Panagiotis , Gkaitatzi Foteini , Gerede Aggeliki , Anthoulaki Xanthoula , Bothou Anastasia , Chalkidou Anna , Michalopoulos Spyridon , Tsirkas Ioannis , Gyroglou Selma , Peitsidis Panagiotis , Nikolettos Konstantinos , Alexiou Alexios , Dragoutsos George , Sachnova Natalia , Chloropoulou Pelagia , Zervoudis Stefanos , Iatrakis George , Rath Werner , Trypsiannis Grigorios , Nikolettos Nikolaos , Souftas Vasileios
Published: December 2022

Objectives: Fibroids cause significant morbidity and are the most common indication for hysterectomies worldwide, delimiting a major public health problem. Uterine artery embolization (UAE) is an alternative therapy to surgical treatment of symptomatic fibroids; it has satisfactory long-time results and is no longer considered investigational for the treatment of symptomatic fibroids. This study was undertaken to evaluate changes in fibroid specific symptom severity and health-related quality of life (HRQOL) after UAE and to optimize the assessment of safety and outcomes measures for participants who receive UAE to objective compare UAE and surgical alternatives for therapy of symptomatic fibroids. Study design: The analysis was based on questionnaires completed by 270 pre-menopausal females with a mean age of 42 years (range, 38–50 years) who underwent UAE for uterine leiomyomas and/or adenomyosis from November 2013 through December 2019. Only symptomatic women were selected whose symptoms were not improving with medication and who did not wish to have children. The primary outcome measure was a change in fibroid symptoms and HRQOL (health related quality of life) after UAE. Secondary outcomes included the decrease in uterine volume after UAE. Results: Questionnaires were completed by 270 women (100%) at a mean of 12.1 months from UAE. The median follow-up period was two years. Uterine fibroid embolization led to a shrinkage at three months for the 90% of the participants. A reduction of bleeding symptoms, pain and bulk-related symptoms was observed in 89.7%, 88.9%, and 89.5% of the patients, respectively. In the long term, there was no significant difference in parameters assessed compared with the midterm follow-up findings. A total of 6 patients (2.3%) underwent fractional curettage an average of 32.1 months after intervention due to necrotic changes in submucosal fibroids. All participants continued to be satisfied with the intervention, and 240 patients (88.9%) answered that they would recommend uterine fibroid embolization to other patients. Conclusions: Women who undergo UAE have a significant decrease in symptom severity and increase in HRQOL which is associated with high levels of satisfaction with the procedure (even when subsequent therapies are pursued).
Past and Future Changes of Land Use/Land Cover and the Potential Impact on Ecosystem Services Value of Damietta Governorate, Egypt
Authors: El-Hamid Hazem T. Abd , Nour-Eldin Hoda , Rebouh Nazih Y. , El-Zeiny Ahmed M.
Published: December 2022

This investigation aims to assess the changes of Land Use/Land Cover (LULC) and its impact on ecosystem services value in Damietta Governorate, Egypt. To fulfill this aim, Landsat data of TM5 in 2001, ETM in 2011 and OLI in 2021 were used. The Maximum Likelihood Classifier was employed to track the changes in LULC of the study area. Cellular automata (CA) and Markov model adopted from IDRISI software were used for accurate prediction of the LULC in 2031. The VALIDATE model in TerrSet was used to compare the predicted 2031 LULC with actual 2021 LULC to assess the accuracy of the model. The Millennium Ecosystem Assessment was utilized to assess the value per unit area of land types. The results indicated that there was a noticeable change in different land cover classes during the duration 2001–2021. Results showed that there are decreases in the cultivated area and the bare area, meanwhile the urban area was increased. The cultivated area was remarkably decreased recording 548.2 km2 (62.15%) at 2001, 548.2 km2 (55.79%) at 2011 and 468.96 km2 (53.16%) at 2021 of the total study area. However, the percentage of urban area increased; reporting 65.69 km2 (7.45%), 124.57 km2 (14.12%), and 176.67 km2 (20.03%) at 2001, 2011, and 2021, respectively. LULC analyses in 2031 showed an increase in the urban area by 2.8% and a decrease in the cultivated area by 7.2%. The kappa index values are greater than 0.80, which shows a strong agreement between simulated and predicted LULC maps. The comprehensive index of Damietta Governorate ranges from 100 to 400. The ES that experienced positive ESV changes during the study period gives strength indicator for achieving the sustainable development of Damietta Governorate. To prevent further ecosystem degradation and to ensure the best possible delivery of ES, it is necessary to reduce the current drivers of LULC changes within the buildup in agricultural land. The study helps the local authorities to better understand the land use system and to develop an improved land use management strategies that manage the urban expansion and guarantee the ecological conservation.
Effects of Landscape Patterns on the Concentration and Recovery Time of PM2.5 in South Korea
Authors: Yoon Sungsoo , Heo Youngdae , Park Chan-Ryul , Kang Wanmo
Published: December 2022

Landscape and urban planning efforts aimed at mitigating the risk of PM2.5 exposure have been hindered by the difficulties in identifying the effects of landscape factors on air pollutants. To identify interactions between PM2.5 and landscape elements, this study explored the contributions of landscape variables at multiple scales to the mean hourly PM2.5 concentration and the duration of high PM2.5 levels in South Korea. We found that the hourly mean PM2.5 concentration was significantly correlated with landscape variables that explained the spatial processes contributing to fluctuations in air pollutants on a regional level while controlling the spatial autocorrelation of regression residuals. On the other hand, a constant, high PM2.5 level was related to landscape patterns that explained relatively independent spatial processes on local levels; these processes include vegetation’s ability to reduce PM2.5 dispersion rates and the influence of transient human activities in local buildings or heavy traffic on roadways on the emission of air pollutants. Our results highlight that urban planners looking to establish design priorities and leverage landscape factors that could reduce the negative impact of PM2.5 on citizens’ health should consider both the more general PM2.5 patterns that exist at regional levels as well as local fluctuations in PM2.5.
Spatial Change of the Farming–Pastoral Ecotone in Northern China from 1985 to 2021
Authors: Li Zongmei , Li Lanhui , Wang Yang , Man Wang , Liu Wenfeng , Nie Qin
Published: December 2022

Identifying the spatial changes in farming–pastoral ecotone (FPE) is of utmost importance for the development of strategies for ecological protection in ecologically fragile areas. This study employed spatial autocorrelation and spatial clustering techniques to map FPE at the pixel scale using CLCD data with a spatial resolution of 30 × 30 m in the years 1985, 2000, and 2021, and then analyzed the changes of the FPE in northern China. The results showed that the FPE is mainly located at the border between the Inner Mongolia Autonomous Region and the adjacent provinces, which is along the Hu-line and the 400-mm isohyetal line. The area of the FPE was 63.94 × 104 km2, 62.90 × 104 km2, and 53.81 × 104 km2 in 1985, 2000, and 2021, respectively, accounting for 6.7%, 6.6%, 5.6% of the total land area in China. The FPE boundary moved northwestward during 1985–2021, demonstrating retreating, fragmenting, and shrinking tendencies. The decreased areas and the moving distances of the gravity center are six times and four times greater during 2000–2021 than that during 1985–2000, respectively. Moreover, the discontinuous change in FPE was mainly due to the increase in forest land, especially for the conversion of grassland to forest land. Our findings provide guidance for the construction of ecological civilization and the optimization of ecosystem structure in the farming–pastoral ecotone.
Comparison of Random Forest and Kriging Models for Soil Organic Carbon Mapping in the Himalayan Region of Kashmir
Authors: Farooq Iqra , Bangroo Shabir Ahmed , Bashir Owais , Shah Tajamul Islam , Malik Ajaz A. , Iqbal Asif M. , Mahdi Syed Sheraz , Wani Owais Ali , Nazir Nageena , Biswas Asim
Published: December 2022

The knowledge about the spatial distribution of soil organic carbon stock (SOCS) helps in sustainable land-use management and ecosystem functioning. No such study has been attempted in the complex topography and land use of Himalayas, which is associated with great spatial heterogeneity and uncertainties. Therefore, in this study digital soil mapping (DSM) was used to predict and evaluate the spatial distribution of SOCS using advanced geostatistical methods and a machine learning algorithm in the Himalayan region of Jammu and Kashmir, India. Eighty-three soil samples were collected across different land uses. Auxiliary variables (spectral indices and topographic parameters) derived from satellite data were used as predictors. Geostatistical methods—ordinary kriging (OK) and regression kriging (RK)—and a machine learning method—random forest (RF)—were used for assessing the spatial distribution and variability of SOCS with inter-comparison of models for their prediction performance. The best fit model validation criteria used were coefficient of determination (R2) and root mean square error (RMSE) with resulting maps validated by cross-validation. The SOCS concentration varied from 1.12 Mg/ha to 70.60 Mg/ha. The semivariogram analysis of OK and RK indicated moderate spatial dependence. RF (RMSE = 8.21) performed better than OK (RMSE = 15.60) and RK (RMSE = 17.73) while OK performed better than RK. Therefore, it may be concluded that RF provides better estimation and spatial variability of SOCS; however, further selection and choice of auxiliary variables and higher soil sampling density could improve the accuracy of RK prediction.
A Syntactical Spatio-Functional Analysis of Four Typical Historic Chinese Towns from a Heritage Tourism Perspective
Authors: Liao Pan , Yu Rongrong , Gu Ning , Soltani Sahar
Published: December 2022

This study presents a quantitative approach to exploring the spatio-functional characteristics of historic Chinese towns (HCTs) from a heritage tourism perspective. In recent years, HCTs have evolved from being resident-oriented to being more tourist-oriented, in part due to their heritage significance for attracting tourists. Spatio-functional qualities of a historic town are essential elements of the town’s urban morphology and of great concern for preservation. Previous studies that discussed this issue often used qualitative descriptions, and only limited studies have systematically explored the spatio-functional qualities of HCTs. Thus, there is presently a lack of understanding around this issue, especially based on rigorous quantitative approaches. This study examines the spatio-functional qualities of HCTs using space syntax, a commonly used method in urban studies that enables measurement of spatial characteristics through mathematical means. Four HCTs with heritage significance, Pingyao, Lijiang, Kulangsu, and Wuzhen, were selected as case studies. The study has examined the role of heritage tourism and the results show that tourist-focused functions tend to distribute and aggregate in the urban core of HCTs. By contrast, cultural relics are freely distributed and not expanded over time. Spatio-functional patterns of the four HCTs were theorised, and the paper concludes with suggestions regarding future land-use optimisation for the four HCTs concerning heritage tourism.
Effects of Hot Isostatic Pressing on the Properties of Laser-Powder Bed Fusion Fabricated Water Atomized 25Cr7Ni Stainless Steel
Authors: Arumugham Akilan Arulselvan , Enneti Ravi K , Balla Vamsi Krishna , Atre Sundar V.
Published: December 2022

25Cr7Ni stainless steel (super duplex stainless steels) exhibits a duplex microstructure of ferrite and austenite, resulting in an excellent combination of high strength and corrosion resistance. However, Laser-Powder Bed Fusion fabrication of a water-atomized 25Cr7Ni stainless steel of novel chemical composition resulted in a purely ferritic microstructure and over 5% porosity. The current study investigated the effects of two hot isostatic pressing parameters on the physical, mechanical, and corrosion properties as well as microstructures of water-atomized 25Cr7Ni stainless steel of novel composition fabricated by L-PBF for the first time in the literature. The corrosion behaviour was studied using linear sweep voltammetry in a 3.5% NaCl solution. The Hot Isostatic Pressing-treated sample achieved over 98% densification with a corresponding reduction in porosity to less than 0.1% and about 3~4% in annihilation of dislocation density. A duplex microstructure of ferrite 60% and austenite 40%was observed in the X-Ray Diffraction and etched metallography of the HIP-treated samples from a purely ferritic microstructure prior to the HIP treatment. With the evolution of austenite phase, the HIP-treated samples recorded a decrease in Ultimate Tensile Strength, yield strength, and hardness in comparison with as-printed samples. The variation in the morphology of the evolved austenite grains in the HIP-treated samples was observed to have a significant effect on the elongation. With a reduction in porosity and the evolution of the austenite phase, the HIP-treated samples showed a higher corrosion resistance in comparison with the as-printed samples.
Experimental and 3D-Deform Finite Element Analysis on Tool Wear during Turning of Al-Si-Mg Alloy
Authors: Okokpujie Imhade P. , Chima Prince C. , Tartibu Lagouge K.
Published: December 2022

Aluminum alloys are becoming increasingly significant in the manufacturing industry due to their light weight and durable properties. Widely applied in aerospace and construction, precision machining is required to ensure the best possible surface quality. The surface quality of a machined component is directly affected by the tool wear incurred during machining. This research investigated the effect of process parameters and machining conditions on tool wear. The critical process parameters selected were cutting speed, feed rate, and depth of cut. Multi-walled carbon nanotube particles were dispersed in a base fluid of mineral oil to create a new lubricant applied during machining. Pure mineral oil was also used as a lubricant to reduce friction. Machining experiments were carried out with the two lubricants, and the tool wear incurred was measured and compared using a Dinolite microscope. All experiments were carried out with high-speed steel (HSS) cutting tools. Taguchi’s L9 orthogonal array was employed as a methodology to design the experiments. A finite-element 3D simulation was also carried out using DEFORM-3D to provide a scientific explanation of the turning process. Results showed a significant reduction in tool wear when machining with multi-walled carbon nanotubes (MWCNTs), with an average reduction of 14.8% compared to mineral oil. The depth of cut was also the most influential process parameter in terms of tool wear.
Biological Durability of Wood–Polymer Composites—The Role of Moisture and Aging
Authors: Buschalsky Andreas , Brischke Christian , Klein Kim Christian , Kilian Thomas , Militz Holger
Published: December 2022

Knowledge about the resistance of wood–polymer composites (WPCs) to biological attack is of high importance for purpose-oriented use in outdoor applications. To gain this knowledge, uniform test methods are essential. EN 15534-1 (2018) provides a general framework, including the recommendation of applying a pre-weathering procedure before the biological laboratory tests. However, the procedure’s manner is not specified, and its necessity assumes that a durability test without such pre-weathering will not produce the structural changes that occur during outdoor use. To verify this assumption, this study examined the influence of natural, ground-level pre-weathering on the material properties of different WPC variants, which were tested at intervals of six months in four durability tests under laboratory conditions in accordance with EN 15534-1 (2018). Weathering factors were calculated from determined characteristic values such as mass loss, and loss in moduli of elasticity (MOE) and rupture (MOR). The weathering factors based on mechanical properties tended to decrease with increasing weathering duration. The expected negative influence of pre-weathering on these material properties was thus not confirmed. The weathering factors based on mass loss were subject to high variation. No significant effect of pre-weathering on mass loss due to fungal attack became evident. Overall, the necessity of a pre-weathering step in biological durability tests shall be questioned based on the presented results.
Gas Permeability Evolution of Coal with Inclusions under Triaxial Compression-Lab Testing and Numerical Simulations
Authors: Zhao Yufeng , Konietzky Heinz , Frühwirt Thomas , Zhou H.W.
Published: December 2022

Coalbed methane (CBM) exploitation leads to permanent stress redistributions in the coal bodies connected with fracturing processes and permeability changes due to deformation induced internal pore-fracture networks. Gas permeability evolution of coal samples is investigated with a newly developed three-dimensional fluid-mechanical coupled experimental system. X-ray CT is used to investigate the internal structure of the coal samples and delivers the basis to set-up numerical twins. The work focuses on coal samples with inclusions. A novel coupling procedure between two different tools—discontinuum and continuum codes—is established to simulate the permeability evolution. The permeability is related to the crack pattern in general, and crack width in particular. A prediction of permeability is proposed based on fracture distribution and microcrack behavior. The experimental studies validated the coupling approach. Shear fractures cause substantial permeability enhancement. Piecewise relations between permeability and volumetric strain can be used to fit the whole process, where a nonlinear exponential relation is established after the expansion point. The inclusions as important structural characteristics influence this relation significantly.
Comparative Analysis of Current and Voltage THD at Different Grid Powers for Powerful Active Front-End Rectifiers with Preprogrammed PWM
Authors: Maklakov Alexander S. , Jing Tao , Nikolaev Alexander A.
Published: December 2022

Preprogrammed pulse width modulation (PPWM) techniques are drawing a great deal of interest due to their strong harmonic performance. However, there have not yet been any systematic studies or elaboration of the influence of different grid powers on current and voltage THD using PPWM. Therefore, this article focuses on a comparative analysis of current and voltage THD in a system with a three-phase, three-level active front-end (AFE) at different grid powers by applying PPWM. A six-pulse electric drive power circuit and one laboratory measurement platform were designed and set up to achieve the above goals. The comparative results were calculated up to the 50th (THD50) and 100th (THD100) harmonics against the frequency of the PPWM, ranging between 150 Hz and 750 Hz. The grid power and AFE power ratio was between 30 and 230 under three different AFE-consumed currents. The experimental results were analyzed and compared, and they demonstrated for the first time how the grid power and AFE power ratio with different PPWM patterns can influence current and voltage THD. The research results suggest that it is necessary to review the existing calculation methods for current and voltage THD using modern electric power quality standards. The results presented in this article also provide a reference point for researchers and engineers when considering the electromagnetic compatibility (EMC) of nonlinear consumers in the design of similar circuits.
Digital Twin-Based Analysis and Optimization for Design and Planning of Production Lines
Authors: Lee Donggun , Kim Chong-Keun , Yang Jinho , Cho Kang-Yeon , Choi Jonghwan , Noh Sang-Do , Nam Seunghoon
Published: December 2022

With the increasing dynamic nature of customer demand, production, product, and manufacturing design changes have become more frequent. Moreover, inadequate validation during the manufacturing design phase may result in additional issues, such as process redesign and layout reallocation, during the operation phase. Therefore, systems that can pre-validate and allow accurate and reliable analysis in the manufacturing design phase, as well as apply and optimize variations in production lines in real time, are required. Previously, digital twin (DT) has been studied a lot in product design and facility prognostics and management fields. Research on the system framework leading to DT utilization and optimization and analysis through DT in complex manufacturing systems with continuous processes such as production lines is insufficient. In this study, a system based on a DT and simulation results is developed; this system can reflect, analyze, and optimize dynamic changes in the design of processes and production lines in real time. First, the framework and application of the proposed system are designed. Subsequently, optimization methodologies based on heuristics and reinforcement learning (RL) are developed. Finally, the effectiveness and applicability of the proposed system are verified by implementing an actual DT application at a real manufacturing site.
Biodiesel Production from Macroalgae Oil from Fucus vesiculosus Using Magnetic Catalyst in Unconventional Reactor Assisted by Magnetic Field
Authors: Silveira Junior Euripedes Garcia , de Souza Lilian Fiori Boechat , Perez Victor Haber , Justo Oselys Rodriguez , Simionatto Euclésio , de Oliveira Lincoln Carlos Silva
Published: December 2022

A novel magnetic catalyst with hollow cylinder shape based on K2CO3/γ-Al2O3/Sepiolite/CoFe2O4 was prepared to convert macroalgae oil (Fucus vesiculosus) into biodiesel in an unconventional reactor assisted by magnetic field. Catalysts were formulated by the extrusion and characterized satisfactorily by physicochemical (mechanical strength, XRD, TG/DTG, FTIR and TPD-CO2), magnetic (VSM and EPR), morphological (SEM) and textural properties (BET). While their catalytic performance was also evaluated at 70 °C, oil: ethanol molar ratio 1:12 and 6 wt.% of catalyst using two different reaction systems for comparative purposes: (a) conventional stirred reactor and (b) fluidized bed reactor assisted by a magnetic field. The attained biodiesel presents properties in accordance with the standard limits (ASTM and EN) and total conversion (>99%) was observed in both cases after 2 h of reaction without significant differences between the two reactors. However, the magnetic properties of these catalysts allowed stabilization of the bed under a magnetic field and easy magnetic catalyst separation/recovery at the reaction end, showing their great potential for biodiesel production with regard to conventional process and thus, transforming it into a more sustainable technology.
Mathematical Expressions Useful for Tunable Properties of Simple Square Wave Generators
Authors: Sotner Roman , Jerabek Jan
Published: December 2022

This paper compares two electronically controllable solutions of triangular and square wave generators benefiting from a single IC package including all necessary active elements (modular cells fabricated in I3T 0.35 µm ON Semiconductor process operating with ±1.65 V supply voltage). Internal cells are used for construction of building blocks of the generator (integrator and Schmitt trigger/comparator). Proposed solutions have adjustable parameters dependent on the values of DC control voltages and currents. Attention is given to the mathematical expressions for the advantageous tunability of these generators. Theoretical mathematical functions comparing the standard linear formula with special expression for the frequency adjustment are evaluated and compared with experimentally obtained results. Mathematical functions prove that the proposed topologies improve efficiency of tunability and reduce overall complexity of both generators. Features of proposed solutions were verified experimentally. Both single-parameter tunable designs target on the operation in bands from tens to hundreds of kHz (from 13 kHz up to 251 kHz for the driving voltage between 0.05 V and 1.0 V for the first solution; from 12 kHz up to 847 kHz for the driving current between 5 µA and 140 µA for the second solution). A comparison with similar solutions indicates beneficial performance of the proposed solutions in tunability ratio vs. driving parameter ratio and also because simplicity of circuitry is low. The qualitative evaluation and comparison of parameters of both circuits is given and confirms theoretical expectations.
A Non-Archimedean Interior Point Method and Its Application to the Lexicographic Multi-Objective Quadratic Programming
Authors: Fiaschi Lorenzo , Cococcioni Marco
Published: December 2022

This work presents a generalized implementation of the infeasible primal-dual interior point method (IPM) achieved by the use of non-Archimedean values, i.e., infinite and infinitesimal numbers. The extended version, called here the non-Archimedean IPM (NA-IPM), is proved to converge in polynomial time to a global optimum and to be able to manage infeasibility and unboundedness transparently, i.e., without considering them as corner cases: by means of a mild embedding (addition of two variables and one constraint), the NA-IPM implicitly and transparently manages their possible presence. Moreover, the new algorithm is able to solve a wider variety of linear and quadratic optimization problems than its standard counterpart. Among them, the lexicographic multi-objective one deserves particular attention, since the NA-IPM overcomes the issues that standard techniques (such as scalarization or preemptive approach) have. To support the theoretical properties of the NA-IPM, the manuscript also shows four linear and quadratic non-Archimedean programming test cases where the effectiveness of the algorithm is verified. This also stresses that the NA-IPM is not just a mere symbolic or theoretical algorithm but actually a concrete numerical tool, paving the way for its use in real-world problems in the near future.
Solution Properties of a New Dynamic Model for MEMS with Parallel Plates in the Presence of Fringing Field
Authors: Di Barba Paolo , Fattorusso Luisa , Versaci Mario
Published: December 2022

In this paper, starting from a well-known nonlinear hyperbolic integro-differential model of the fourth order describing the dynamic behavior of an electrostatic MEMS with a parallel plate, the authors propose an upgrade of it by formulating an additive term due to the effects produced by the fringing field and satisfying the Pelesko–Driscoll theory, which, as is well known, has strong experimental confirmation. Exploiting the theory of hyperbolic equations in Hilbert spaces, and also utilizing Campanato’s Near Operator Theory (and subsequent applications), results of existence and regularity of the solution are proved and discussed particularly usefully in anticipation of the development of numerical approaches for recovering the profile of the deformable plate for a wide range of applications.
On the Order of Convergence of the Noor–Waseem Method
Authors: George Santhosh , Sadananda Ramya , Padikkal Jidesh , Argyros Ioannis K.
Published: December 2022

In 2009, Noor and Waseem studied an important third-order iterative method. The convergence order is obtained using Taylor expansion and assumptions on the derivatives of order up to four. In this paper, we have obtained convergence order three for this method using assumptions on the first and second derivatives of the involved operator. Further, we have extended the method to obtain a fifth- and a sixth-order methods. The dynamics of the methods are also provided in this study. Numerical examples are included. The same technique can be used to extend the utilization of other single or multistep methods.