The 2023 MDPI Annual Report has
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21 pages, 12687 KiB  
Article
Towards Enhanced Understanding and Experience of Landforms, Geohazards, and Geoheritage through Virtual Reality Technologies in Education: Lessons from the GeoVT Project
by Vittoria Vandelli, Piotr Migoń, Ylva Palmgren, Evangelos Spyrou, Giannis Saitis, Maria Eleni Andrikopoulou, Paola Coratza, Mohand Medjkane, Carmen Prieto, Konstantinos Kalovrektis, Candide Lissak, Alexandros Papadopoulos, Nikos Papastamatiou, Niki Evelpidou, Olivier Maquaire, Sarantos Psycharis, Arjen P. Stroeven and Mauro Soldati
Geosciences 2024, 14(5), 127; https://doi.org/10.3390/geosciences14050127 (registering DOI) - 06 May 2024
Abstract
Virtual reality is a technological development that, among others, has revolutionized Earth sciences. Its advantages include an opportunity to examine places otherwise difficult or impossible to access and it may also become an important component of education, fostering a better understanding of processes [...] Read more.
Virtual reality is a technological development that, among others, has revolutionized Earth sciences. Its advantages include an opportunity to examine places otherwise difficult or impossible to access and it may also become an important component of education, fostering a better understanding of processes and landforms, geohazard awareness, and an appreciation of geoheritage. This paper reports on the GeoVT project, which aims to create a platform to build and disseminate Virtual Field Trips (VFTs) focused on geomorphology, natural hazards associated with geomorphological processes, and geoheritage sites. To put the GeoVT project in context, an overview of applications of VR in geosciences is provided. This paper subsequently proceeds with a presentation of the project and the GeoVT Authoring application, which is an innovative platform designed to help teachers and students, followed by brief presentations of a number of VFTs developed within the project. They address themes such as fluvial landforms and valley development, coastal landforms, evidence of past glaciation, coastal erosion, wildfire effects, mud volcanoes, and landslides. Full article
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18 pages, 9458 KiB  
Article
Collaborative Methods of Resolving Road Graphic Conflicts Based on Cartographic Rules and Generalization Operations
by Chuanbang Zheng, Qingsheng Guo, Lin Wang, Yuangang Liu and Jianfeng Jiang
ISPRS Int. J. Geo-Inf. 2024, 13(5), 154; https://doi.org/10.3390/ijgi13050154 (registering DOI) - 06 May 2024
Abstract
The resolution of road graphic conflicts is a key aspect of map generalization, which involves both scale reduction and the symbolization of map features. This study proposes collaborative methods of road graphic conflict resolution considering different road characteristics. These methods consider both geometric [...] Read more.
The resolution of road graphic conflicts is a key aspect of map generalization, which involves both scale reduction and the symbolization of map features. This study proposes collaborative methods of road graphic conflict resolution considering different road characteristics. These methods consider both geometric and semantic characteristics, and they incorporate the bend characteristics of roads, the road symbol size, and road semantics. Constrained Delaunay triangulation skeleton lines are used to categorize road graphic conflicts, which are made up of four independent conflict types and four group conflict types. Based on their characteristics, three collaborative methods are designed to deal with the different types of road graphic conflicts: collaboration between deletion and the snake displacement model, collaboration between the snake displacement model and collinearity, and collaboration among simplification, smoothing, and the beam displacement model. Two types of independent conflicts can be processed using only one simple operation. This study summarizes the cartographic rules for resolving road graphic conflicts, and these are used along with geometric features to drive the collaborative methods or one simple operation presented here. The experimental results indicate that the method proposed in this study can effectively resolve road graphic conflicts. Full article
16 pages, 663 KiB  
Article
Influences of a Supplemental Blend of Essential Oils plus 25-Hydroxy-Vit-D3 and Zilpaterol Hydrochloride (β2 Agonist) on Growth Performance and Carcass Measures of Feedlot Lambs Finished under Conditions of High Ambient Temperature
by Alfredo Estrada-Angulo, Moisés Verdugo-Insúa, Lucía de G. Escobedo-Gallegos, Beatriz I. Castro-Pérez, Jesús D. Urías-Estrada, Elizama Ponce-Barraza, Daniel Mendoza-Cortez, Francisco G. Ríos-Rincón, Francisco Monge-Navarro, Alberto Barreras, Richard A. Zinn, Luis Corona-Gochi and Alejandro Plascencia
Animals 2024, 14(9), 1391; https://doi.org/10.3390/ani14091391 (registering DOI) - 06 May 2024
Abstract
Forty-eight Pelibuey × Katahdin male intact lambs (25.12 ± 3.79 kg LW) were used in a 70-d growing-finishing trial. Dietary treatments consisted of total mixed corn-based diet supplemented with: (1) no feed additives (Control); (2) 150 mg of essential oils blend plus 0.10 [...] Read more.
Forty-eight Pelibuey × Katahdin male intact lambs (25.12 ± 3.79 kg LW) were used in a 70-d growing-finishing trial. Dietary treatments consisted of total mixed corn-based diet supplemented with: (1) no feed additives (Control); (2) 150 mg of essential oils blend plus 0.10 mg of 25-hydroxy-Vit-D3/kg diet offered throughout the 70-d experimental period (EOD3); (3) Control diet fed during the first 35 days and zilpaterol hydrochloride (ZH) supplementation at 6 mg/kg diet offered during the final 35 days of the experiment (32 days with ZH with a withdrawal 3-d before harvest), and (4) basal diet supplemented with EOD3 during first 35 days finishing, and EOD3 in combination with ZH (EOD3 + ZH) during the subsequent 32-days with ZH withdrawal 3 days before harvest. The temperature–humidity index during the experiment averaged 80.4 ± 3.2. There were no treatment interactions (p > 0.20) on growth performance and carcass measures. Supplemental EOD3 did not affect (p = 0.43) dry matter intake (DMI), but increased (p < 0.01) carcass adjusted average daily gain (ADG, 9.2%), gain efficiency (GF, 6.7%), and observed vs. expected dietary net energy for maintenance (NEm, 4.8%) and for gain (NEg, 6.4%). Supplemental ZH did not affect dry matter intake (DMI, p = 0.50) but increased (p < 0.01) carcass adjusted ADG (14.5%), GF (13%) and observed vs. expected dietary NEm (9%) and NEg (11.7%). Compared to control lambs, the combination of both additives increased ADG (24.9%), GF (21.2%), and observed vs. expected dietary NEm and NEg (14.2% and 18.9%, respectively). There were no treatment interactions on carcass characteristics, visceral organ mass, or on gene expression of IGF1, IGF2 and mTOR in longissimus muscle (LM). Supplemental EOD3 increased hot carcass weight (HCW; 4.0%, p < 0.01) but did not affect other carcass measures. Supplemental EOD3 decreased (3%, p = 0.03) intestine mass weight (g intestine/kg empty body weight). Supplemental ZH increased HCW (6%, p < 0.01), dressing percentage (1.7%, p = 0.04), and LM area (9.7%, p < 0.01), and decreased kidney-pelvic-fat percentage (16.2%, p < 0.01), fat thickness (14.7%, p = 0.03), and visceral fat. Compared to controls, the combination of EOD3 with ZH increased HCW (10.2%). It is concluded that growth performance responses to supplemental EOD3 and ZH are additive. Both supplements can be fed in combination without detrimental effects on expected benefits when fed separately. In addition, ZH supplementation improves carcass traits. Full article
(This article belongs to the Special Issue Feed Additives, Performance and Welfare in Domestic Animals)
25 pages, 915 KiB  
Article
Application of Epidemiological Methods in a Large-Scale Cross-Sectional Study in 765 German Dairy Herds—Lessons Learned
by Roswitha Merle, Martina Hoedemaker, Gabriela Knubben-Schweizer, Moritz Metzner, Kerstin-Elisabeth Müller and Amely Campe
Animals 2024, 14(9), 1385; https://doi.org/10.3390/ani14091385 (registering DOI) - 06 May 2024
Abstract
From 2016 to 2020, the “PraeRi” study, conducted by three German veterinary universities, was aimed at enhancing animal health and welfare in dairy farms. With 765 dairy farms visited and 101,307 animals examined, this study provided a basis for improving animal health and [...] Read more.
From 2016 to 2020, the “PraeRi” study, conducted by three German veterinary universities, was aimed at enhancing animal health and welfare in dairy farms. With 765 dairy farms visited and 101,307 animals examined, this study provided a basis for improving animal health and welfare. The study population comprised three different regions representing a broad variety of characteristics. To ensure representative estimates, a sample size of 250 farms was determined for each region, employing a stratified sampling plan based on farm size. According to the information provided by the farmers, the most commonly occurring disease in their herds was mastitis without general disorder (14.2% to 16.3% of the herd—depending on the region). For most disorders, prevalence data were lowest for the region South compared with the two remaining regions. Multivariable regression analyses were performed to identify risk factors for various target variables, and the results were communicated through individual reports and benchmarking flyers to participating farmers. The authors encountered challenges in management and communication due to the project’s size in terms of personnel, data, and farms examined. Harmonizing data management and hypothesis testing across all involved parties added complexity. Full article
(This article belongs to the Special Issue Disease Epidemiology in Farm Animal Production)
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15 pages, 2087 KiB  
Article
Physical and Chemical Characteristics of Droppings as Sensitive Markers of Chicken Health Status
by Erika Mozuriene, Ernestas Mockus, Dovile Klupsaite, Vytaute Starkute, Ernesta Tolpeznikaite, Valentas Gruzauskas, Romas Gruzauskas, Agne Paulauskaite-Taraseviciene, Vidas Raudonis and Elena Bartkiene
Animals 2024, 14(9), 1389; https://doi.org/10.3390/ani14091389 (registering DOI) - 06 May 2024
Abstract
The aim of this study was to analyze the physical and chemical characteristics of chicken droppings (n = 73), which were collected during different age periods and classified by visual inspection into normal (N) and abnormal (A). Significant differences were found in the [...] Read more.
The aim of this study was to analyze the physical and chemical characteristics of chicken droppings (n = 73), which were collected during different age periods and classified by visual inspection into normal (N) and abnormal (A). Significant differences were found in the texture, pH, dry matter (DM), fatty acids (FAs), short-chain fatty acids (SCFAs), and volatile compounds (VCs) between the tested dropping groups (p ≤ 0.05). The age period of the chicken had a significant influence on the color coordinates, texture, pH, DM, and SCFA contents in N and A as well as on all FAs content in N (p ≤ 0.05). Droppings from the N group had a harder texture, lower values of a* and b* color coordinates, higher DM content, higher level of linoleic FA, and lower level of α-linolenic FA than the droppings from the A group in each age period (p ≤ 0.05). The predominant SCFA was acetic acid, the content of which was significantly lower in the N group compared to that of the A group. The alcohol and organic acid contents were the highest in most of the A group at different age periods, while ketones dominated in the N and A groups. In conclusion, the majority of the tested dropping characteristics were influenced by the age period. While certain characteristics demonstrate differences between N and A, a likely broader range of droppings is required to provide more distinct trends regarding the distribution of characteristics across different droppings. Full article
(This article belongs to the Collection Poultry Feeding and Gut Health)
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23 pages, 7657 KiB  
Article
An Interactive Feeder to Induce and Assess Emotions from Vocalisations of Chickens
by Antonis Golfidis, Buddhamas Pralle Kriengwatana, Mina Mounir and Tomas Norton
Animals 2024, 14(9), 1386; https://doi.org/10.3390/ani14091386 (registering DOI) - 06 May 2024
Abstract
Understanding the emotional states of animals is a long-standing research endeavour that has clear applications in animal welfare. Vocalisations are emerging as a promising way to assess both positive and negative emotional states. However, the vocal expression of emotions in birds is a [...] Read more.
Understanding the emotional states of animals is a long-standing research endeavour that has clear applications in animal welfare. Vocalisations are emerging as a promising way to assess both positive and negative emotional states. However, the vocal expression of emotions in birds is a relatively unexplored research area. The goal of this study was to develop an interactive feeding system that would elicit positive and negative emotional states, and collect recordings of the vocal expression of these emotions without human interference. In this paper, the mechatronic design and development of the feeder is described. Design choices were motivated by the desire for the hens to voluntarily interact with the feeder and experience the different stimuli that were designed to induce (1) positive low-arousal, (2) positive high-arousal, (3) negative low-arousal, and (4) negative high-arousal states. The results showed that hens were motivated to engage with the feeder despite the risk of receiving negative stimuli and that this motivation was sustained for at least 1 week. The potential of using the interactive feeder to analyse chicken vocalisations related to emotional valence and arousal is being explored, offering a novel proof of concept in animal welfare research. Preliminary findings suggest that hens vocalised in response to all four stimulus types, with the number of vocalisations, but not the probability of vocalising, distinguishing between low- and high-arousal states. Thus, the proposed animal–computer interaction design has potential to be used as an enrichment device and for future experiments on vocal emotions in birds. Full article
(This article belongs to the Special Issue Animal–Computer Interaction: Advances and Opportunities)
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14 pages, 4263 KiB  
Article
Prediction of Potential Suitable Distribution Areas for an Endangered Salamander in China
by Jiacheng Tao, Yifeng Hu, Jianping Jiang, Wanji Yang, Tian Zhao and Shengqi Su
Animals 2024, 14(9), 1390; https://doi.org/10.3390/ani14091390 (registering DOI) - 06 May 2024
Abstract
Climate change has been considered to pose critical threats for wildlife. During the past decade, species distribution models were widely used to assess the effects of climate change on the distribution of species’ suitable habitats. Among all the vertebrates, amphibians are most vulnerable [...] Read more.
Climate change has been considered to pose critical threats for wildlife. During the past decade, species distribution models were widely used to assess the effects of climate change on the distribution of species’ suitable habitats. Among all the vertebrates, amphibians are most vulnerable to climate change. This is especially true for salamanders, which possess some specific traits such as cutaneous respiration and low vagility. The Wushan salamander (Liua shihi) is a threatened and protected salamander in China, with its wild population decreasing continuously. The main objective of this study was to predict the distribution of suitable habitat for L. shihi using the ENMeval parameter-optimized MaxEnt model under current and future climate conditions. Our results showed that precipitation, cloud density, vegetation type, and ultraviolet radiation were the main environmental factors affecting the distribution of L. shihi. Currently, the suitable habitats for L. shihi are mainly concentrated in the Daba Mountains, including northeastern Chongqing and western Hubei Provinces. Under the future climate conditions, the area of suitable habitats increased, which mainly occurred in central Guizhou Province. This study provided important information for the conservation of L. shihi. Future studies can incorporate more species distribution models to better understand the effects of climate change on the distribution of L. shihi. Full article
(This article belongs to the Special Issue Protecting Endangered Species)
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13 pages, 4679 KiB  
Article
Identification Algorithm for Stability Improvement of Welding Robot End-Effector
by Lijian Liu, Yongkang Zhang, Bin Wei and Guang Yang
Actuators 2024, 13(5), 175; https://doi.org/10.3390/act13050175 (registering DOI) - 06 May 2024
Abstract
Aiming to solve the problem that the significant error between the actual joint torque and the calculated joint torque of a welding robot leads to the vibration of the end-effector, which in turn affects the stability of the end-effector, this paper proposes a [...] Read more.
Aiming to solve the problem that the significant error between the actual joint torque and the calculated joint torque of a welding robot leads to the vibration of the end-effector, which in turn affects the stability of the end-effector, this paper proposes a identification algorithm based on the Weighted Least Squares Genetic Algorithm (WLS-GA) to construct and solve the dynamical model to obtain the accurate dynamical parameters. Firstly, a linear model of welding robot dynamics is derived. The fifth-order optimal Fourier series excitation trajectory is designed to collect experimental data such as joint torque. Then, a rough solution of the parameters to be recognized is obtained by solving the dynamics model through the Weighted Least Squares (WLS) method, the search space is determined based on the rough solution, and the optimal solution is obtained by using the Genetic Algorithm (GA) to perform a quadratic search in the search space. Finally, the identification data obtained from the algorithm is analyzed and compared with the experimental data. The results show that the error between the identification data obtained using the WLS-GA identification algorithm and the experimental data is relatively small. The results show that the identification data obtained using the WLS-GA identification algorithm have less error than the experimental data, taking the Root Mean Square (RMS) value of the joint torque error obtained using the weighted least squares algorithm as a criterion. The accuracy of the WLS-GA identification algorithm can be improved by up to 66.85% compared with that of the weighted least squares algorithm and by up to 78.0% compared with that of the Ordinary Least Squares (OLS) algorithm. In summary, the WLS-GA identification algorithm can accurately identify the dynamic parameters of the welding robot and more accurately construct a dynamic model to solve the effect of joint torque error on the control characteristics of the welding robot. It can improve the stability of the end-effector of the welding robot to ensure the quality of the automobile body and beam welding and welding speed. Full article
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11 pages, 1835 KiB  
Communication
The Effect of κ-Carrageenan on Porcine Sperm Cryo-Survival
by Areeg Almubarak, Eunji Kim, Il-Jeoung Yu, Hanseul Park and Yubyeol Jeon
Animals 2024, 14(9), 1387; https://doi.org/10.3390/ani14091387 (registering DOI) - 06 May 2024
Abstract
κ-Carrageenan is a sulfated polysaccharide from red seaweed with substantial antioxidant activities. This study aimed to investigate the effect of κ-Carrageenan treatment on frozen–thawed (FT) porcine semen quality. Therefore, the spermatozoa were diluted and cryopreserved in a freezing extender supplemented with 0 (control), [...] Read more.
κ-Carrageenan is a sulfated polysaccharide from red seaweed with substantial antioxidant activities. This study aimed to investigate the effect of κ-Carrageenan treatment on frozen–thawed (FT) porcine semen quality. Therefore, the spermatozoa were diluted and cryopreserved in a freezing extender supplemented with 0 (control), 0.2, 0.4, 0.6, and 0.8 mg/mL κ-Carrageenan. Sperm kinematics were assessed immediately after thawing (AT) and post-incubation for 120 min. The viability, acrosome integrity, lipid peroxidation, mitochondrial membrane potential (MMP), and intracellular caspase activity were measured AT. The results indicated that 0.2 mg/mL κ-Carrageenan increased total and progressive motility AT and post-incubation for 120 min (p < 0.05). Moreover, the viable sperm percentage and MMP after 0.2 mg/mL treatment were higher than those after control and other κ-Carrageenan concentration treatments. The proportion of acrosome-intact spermatozoa was significantly higher after 0.2 and 0.4 mg/mL κ-Carrageenan treatment than that after control and other κ-Carrageenan concentration treatments. The intracellular caspase activity was not significantly different among the experimental groups. However, the MDA concentration after 0.2 mg/mL κ-Carrageenan treatment was lower (p < 0.05) than that after the control treatment. Taken together, adding κ-Carrageenan to the porcine semen freezing extender improved the FT sperm quality mainly by influencing membrane stability and protecting against oxidative stress. Full article
(This article belongs to the Section Animal Reproduction)
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9 pages, 2025 KiB  
Communication
The Impact of Environmental Enrichment on the Cortisol Level of Shelter Cats
by Justyna Wojtaś, Piotr Czyżowski, Kamila Kaszycka, Klaudia Kaliszyk and Mirosław Karpiński
Animals 2024, 14(9), 1392; https://doi.org/10.3390/ani14091392 (registering DOI) - 06 May 2024
Abstract
Enriching cats’ living environment in shelters is crucial in reducing their stress. Easier access to resources allows cats to display natural behavior. This study aimed to assess whether cats staying in an enriched environment would be less stressed than cats staying in a [...] Read more.
Enriching cats’ living environment in shelters is crucial in reducing their stress. Easier access to resources allows cats to display natural behavior. This study aimed to assess whether cats staying in an enriched environment would be less stressed than cats staying in a standard environment. The first group consisted of cats living in an environment with fewer resources (standard environment)—103 cats. The second group consisted of cats living in an enriched environment—76 cats. The research material consisted of hair collected to determine the cortisol level. The results indicate that cats from a more enriched environment have almost half the level of cortisol in hair than cats from an environment with fewer resources (0.059 ng/mg vs. 0.101 ng/mg; p = 0.000001). Full article
(This article belongs to the Section Companion Animals)
9 pages, 1405 KiB  
Article
Sperm Incubation in Biggers–Whitten–Whittingham Medium Induces Capacitation-Related Changes in the Lizard Sceloporus torquatus
by Uriel Ángel Sánchez-Rivera, Norma Berenice Cruz-Cano, Alfredo Medrano, Carmen Álvarez-Rodríguez and Martín Martínez-Torres
Animals 2024, 14(9), 1388; https://doi.org/10.3390/ani14091388 (registering DOI) - 06 May 2024
Abstract
Sperm capacitation involves biochemical and physiological changes that enable sperm to fertilize the oocyte. It can be induced in vitro under controlled conditions that simulate the environment of the oviduct. While extensively studied in mammals, its approach in lizards remains absent. Understanding the [...] Read more.
Sperm capacitation involves biochemical and physiological changes that enable sperm to fertilize the oocyte. It can be induced in vitro under controlled conditions that simulate the environment of the oviduct. While extensively studied in mammals, its approach in lizards remains absent. Understanding the mechanisms that ensure reproduction is essential for advancing the implementation of assisted reproductive technologies in this group. We aimed to perform a sperm analysis to determine if capacitation-related changes were induced after incubation with capacitating media. Fifteen males of Sceloporus torquatus were collected during the early stage of the reproductive season. The sperm were isolated from the seminal plasma and then diluted up to a volume of 150 μL using BWW medium to incubate with 5% CO2 at 30 °C for a maximum duration of 3 h. A fraction was retrieved hourly for ongoing sperm assessment. The sperm analysis included assessments of its motility, viability, the capacitation status using the chlortetracycline (CTC) assay, and the acrosome integrity with the lectin binding assay to detect changes during incubation. We found that total motility was maintained up to 2 h post incubation, after which it decreased. However, sperm viability remained constant. From that moment on, we observed a transition to a deeper and less symmetrical flagellar bending in many spermatozoa. The CTC assay indicated a reduction in the percentage of sperm showing the full (F) pattern and an increase in those exhibiting the capacitated (B) and reactive (RA) patterns, accompanied by an elevation in the percentage of damaged acrosomes as revealed by the lectin binding assay. In mammals, these changes are often associated with sperm capacitation. Our observations support the notion that this process may also occur in saurian. While sperm analysis is a valuable method for assessing certain functional changes, additional approaches are required to validate this process. Full article
(This article belongs to the Special Issue Animal Reproduction: Semen Quality Assessment, Volume II)
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16 pages, 543 KiB  
Article
The Role of Digital Inclusive Finance in Weakening Real Estate Market Speculation
by Ruiwen Zhang and Yiran Pang
Buildings 2024, 14(5), 1306; https://doi.org/10.3390/buildings14051306 (registering DOI) - 06 May 2024
Abstract
A multitude of studies have extensively examined strategies for achieving sustainable development in the real estate market. As the pivotal component of land economy, the real estate market plays a crucial role in ensuring its sound operation. However, it is currently undergoing significant [...] Read more.
A multitude of studies have extensively examined strategies for achieving sustainable development in the real estate market. As the pivotal component of land economy, the real estate market plays a crucial role in ensuring its sound operation. However, it is currently undergoing significant adjustments and grappling with rampant speculative activities, resulting in an alarming bubble. By scrutinizing the speculative motivations of different entities, we present a novel perspective on mitigating speculation. Our analysis reveals that digital inclusive finance effectively curbs residents’ and enterprises’ speculative behavior, as evidenced by diminished prevention motivation and investment substitution motivation. Utilizing data from 280 cities, this study measures real estate market speculation by establishing a model that the volatility of the housing market turnover, as a proportion of GDP, deviates from the actual housing demand transactions based on economic fundamentals. Furthermore, it investigates the relationship between digital inclusive finance and real estate market speculation, along with its spatial effects. The findings indicate that digital inclusive finance significantly curbs real estate market speculation and has a negative spatial spillover effect. This research provides a novel model and perspective for exploring real estate market speculation while positively impacting sustainable development within the real estate market. Full article
(This article belongs to the Special Issue Sustainable City Development: Urban Planning and Housing Management)
19 pages, 1654 KiB  
Article
Numerical Study on the Dynamic Response and Damage Cumulative of Bolt-Supported Cavern under Adjacent Cyclic Explosion
by Guangyong Wang, Kaiwen Chang and Ansheng Cao
Buildings 2024, 14(5), 1307; https://doi.org/10.3390/buildings14051307 (registering DOI) - 06 May 2024
Abstract
Adjacent cyclic explosions significantly impact the stability of underground anchored caverns. Based on the similar model test of the vault explosion of the anchored cavern, the dynamic analysis finite element software ANSYS/LSDYNA(18.0) was used to establish a model of the straight wall side [...] Read more.
Adjacent cyclic explosions significantly impact the stability of underground anchored caverns. Based on the similar model test of the vault explosion of the anchored cavern, the dynamic analysis finite element software ANSYS/LSDYNA(18.0) was used to establish a model of the straight wall side explosion of the underground anchored cavern and conduct a numerical simulation. When the total amount of explosion load is the same, we compared the stress time history curve, displacement time history curve, tunnel wall displacement, and circumferential strain curve of the surrounding rock in the underground anchored cavern (under both a high-level single-side blast and a low-level cyclic side blast). We obtained the dynamic response rules of the surrounding rock. By comparing the damage evolution process of the surrounding rock in the two situations, the damage accumulation law of the surrounding rock was analyzed. At the same time, the axial stress distribution characteristics of underground anchor cavern anchors under the action of cyclic explosion were studied. The findings demonstrate that when the total level of blast load adjacent to the cavern is the same, the displacement and circumferential peak strain of surrounding rock and the axial stress of rock bolt in the high-level single explosion are greater than those in the low-level cyclic explosion. However, compared to a single explosion, the rock mass suffers more damage in the cyclic explosion. This study will provide engineers with information that will assist them with a better understanding of the cumulative damage mechanisms of surrounding rock, as well as the stress characteristics of rock bolts under dynamic loads near the explosion site, which will be used to design underground caves with anti-blast features. Full article
(This article belongs to the Section Building Structures)
17 pages, 2683 KiB  
Article
Investigating the Hydration, Mechanical Properties, and Pozzolanic Activity of Cement Paste Containing Co-Combustion Fly Ash
by Xiaobo Ding, Hangyu Du, Enfeng Wu, Peng Yi, Yongqiang Li, Yaoming Luo and Wei Liu
Buildings 2024, 14(5), 1305; https://doi.org/10.3390/buildings14051305 (registering DOI) - 06 May 2024
Abstract
The heat of hydration, mechanical properties, pozzolanic activity, and microscopic characteristics of cement pastes incorporating co-combusted fly ash (CCFA) were investigated, and the disparities between the CCFA/cement system and the coal fly ash (CFA) binding system were also compared. The results indicate a [...] Read more.
The heat of hydration, mechanical properties, pozzolanic activity, and microscopic characteristics of cement pastes incorporating co-combusted fly ash (CCFA) were investigated, and the disparities between the CCFA/cement system and the coal fly ash (CFA) binding system were also compared. The results indicate a decrease in the heat of hydration for both CFA and CCFA samples, with a more pronounced trend observed as the fly ash content increased from 10% to 30%. The distinction in the early hydration between CFA and CCFA samples primarily manifested in the rate of heat release, potentially correlated with variations in the active Al2O3 content in the fly ash. Neither CFA nor CCFA samples exhibited significant cementitious activity at 3 days, functioning solely as inert fillers in the cement paste. By 3 and 28 days, the mechanical properties of both CFA and CCFA samples were inferior to those of pure cement paste. However, by 180 days of hydration, the compressive strength of CCFA-blended mortar notably increased, with the highest strength observed in the 10% CCFA-blended sample. Both CFA and CCFA samples produced the secondary hydration product C-A-S-H and demonstrated comparable consumption of calcium hydroxide (CH). These findings underscore the potential of CCFA as a supplementary cementitious material (SCM) and lay a foundation for its widespread adoption. Full article
(This article belongs to the Section Building Materials, and Repair & Renovation)
16 pages, 2056 KiB  
Article
Evaluating the Effect of Prefabricated Building Incentive Policies Using Structural Equation Modeling: A Chinese Empirical Study
by Weidong Yan, Chunbing Guo and Lihong Li
Buildings 2024, 14(5), 1304; https://doi.org/10.3390/buildings14051304 (registering DOI) - 06 May 2024
Abstract
Building production increases energy demand, which raises carbon dioxide emissions and leads to environmental degradation. The use of prefabricated buildings has the potential to play an important role in promoting sustainable development in the construction industry, and prefabricated building incentive policies (PBIP) are [...] Read more.
Building production increases energy demand, which raises carbon dioxide emissions and leads to environmental degradation. The use of prefabricated buildings has the potential to play an important role in promoting sustainable development in the construction industry, and prefabricated building incentive policies (PBIP) are an effective means of improving the development level of prefabricated buildings (PBDL). This study investigated the significance of PBIP using a structural equation model (SEM) analysis of the results of 519 questionnaire surveys obtained in 10 prefabricated building demonstration cities in China. The results indicate that policy satisfaction has the most substantial impact on PBDL, with direct funding subsidy policy being the most influential factor. Policy application enthusiasm ranks second according to influence on PBDL, while policy awareness has the most negligible impact on PBDL among the examined factors. This research provides a reference for the government to formulate reasonable and effective prefabricated building incentive policies, and it may be useful for promoting the development of prefabricated buildings. Full article
(This article belongs to the Section Construction Management, and Computers & Digitization)
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19 pages, 5235 KiB  
Article
Investigation of the Causes of Soft-Storey and Weak-Storey Formations in Low- and Mid-Rise RC Buildings in Türkiye
by Hakan Ulutaş
Buildings 2024, 14(5), 1308; https://doi.org/10.3390/buildings14051308 (registering DOI) - 06 May 2024
Abstract
This study investigates the causes of soft-storey and weak-storey formations in low- and mid-rise RC (Reinforced Concrete) buildings in Türkiye. In the first phase of the study, 96 model buildings were designated for the examination of soft-storey irregularity when the ground floors are [...] Read more.
This study investigates the causes of soft-storey and weak-storey formations in low- and mid-rise RC (Reinforced Concrete) buildings in Türkiye. In the first phase of the study, 96 model buildings were designated for the examination of soft-storey irregularity when the ground floors are used for commercial purposes and the upper floors for residential use. The ground floor heights that would cause soft-storey irregularity in each of the selected buildings were determined according to the formulas given in the Türkiye Building Earthquake Code (TBEC) and the American Society of Civil Engineers Standard (ASCE). It was found that the ground floor heights obtained according to ASCE are usable in practice, whereas those obtained according to the TBEC, particularly for buildings over three storeys, are excessively high for practical use. This indicates that, even if the buildings in Türkiye are designed with very high ground floor heights, they do not have soft-storey irregularities, according to the TBEC, but soft-storey formation may occur in these buildings due to the high ground floor height as a result of the effects of earthquakes. Instead of the soft-storey irregularity coefficient limit value (nki > 2) found in the TBEC, this study proposes a new limit value to prevent the design of buildings with very high ground floors. In the second phase of the study, for the purpose of examining weak-storey irregularity, 105 model buildings differing in their infill wall layout, number of spans, span length, and number of storeys were selected. The weak-storey irregularity coefficients of each of these models were determined according to the TBEC. The results of the study revealed that buildings with no infill walls in one direction or with infill walls in only one of the exterior axes in one direction have a high risk of having weak storeys. Full article
22 pages, 3801 KiB  
Article
Evaluation of Ground Motion Damage Potential with Consideration of Compound Intensity Measures Using Principal Component Analysis and Canonical Correlation Analysis
by Tingting Liu and Dagang Lu
Buildings 2024, 14(5), 1309; https://doi.org/10.3390/buildings14051309 (registering DOI) - 06 May 2024
Abstract
The primary motivation of this study is to develop a compound intensity measure (IM) to evaluate ground motion damage potential based on principal component analysis (PCA) and canonical correlation analysis (CCA). To illustrate this, this study examines the correlation among intragroup IMs and [...] Read more.
The primary motivation of this study is to develop a compound intensity measure (IM) to evaluate ground motion damage potential based on principal component analysis (PCA) and canonical correlation analysis (CCA). To illustrate this, this study examines the correlation among intragroup IMs and intergroup IMs, as well as the correlation between various IMs and response variables. A compound IM, which can be obtained by a linear combination of ten IMs in the log-scale, is utilized to measure the ground motion damage potential. Elastoplastic, bilinear and hysteretic models are utilized to determine peak deformation and hysteretic energy as the response variables of Single-Degree-of-Freedom (SDOF) systems. On the basis of the SDOF systems, the overall structural damage index is obtained by a nonlinear time–history analysis for two reinforced concrete moment frame systems. It is clear that the developed compound IM shows significantly high-level correlation with structural response. The better the correlations, the more one can measure the earthquake damage potential. A single IM alone inadequately characterizes structural damage, highlighting the necessity of multiple IMs to estimate the possibility of structural damage. Full article
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16 pages, 2553 KiB  
Article
Nejayote and Food Waste Leachate as a Medium for Scenedesmus acutus and Haematococcus pluvialis Production: A Mixture Experimental Design
by Elizabeth Garza-Valverde, Celestino García-Gómez, Juan Nápoles-Armenta, Luis Samaniego-Moreno, Edgardo Martínez-Orozco and Celia De La Mora-Orozco
Water 2024, 16(9), 1314; https://doi.org/10.3390/w16091314 (registering DOI) - 06 May 2024
Abstract
The wastewaters of nejayote and food waste leachate are polluting effluents with a high load of organic matter that cause great problems when discharged to water receptors. In this work, we investigated the treatment of nejayote wastewaters and food waste leachate for the [...] Read more.
The wastewaters of nejayote and food waste leachate are polluting effluents with a high load of organic matter that cause great problems when discharged to water receptors. In this work, we investigated the treatment of nejayote wastewaters and food waste leachate for the production of microalgae Scenedesmus acutus and Haematococcus pluvialis. For Scenedesmus acutus, treatment with 10% food waste leachate and 90% growth medium resulted in a concentration of 5.34 g/L in 20 days (μmax = 0.16/day). Meanwhile, 10% nejayote and 90% medium growth produced 4.45 g/L at 20 days (μmax = 0.13/d). A significant reduction of up to 82.6% ammonium, 84.1% orthophosphate, and 87.25% COD was also observed between the different treatments. For Haematococcus pluvialis, the treatment of 90% food waste leachate and 10% growth medium produced a concentration of 4.73 g/L at 6 days (μmax = 0.71/day), while the mixture of 25% najayote, 25% food waste leachate, and 50% growth medium produced a concentration of 5.5 g/L at 20 days (μmax = 0.25/dat). A reduction of up to 97.8% ammonia, 97.4% orthophosphate, and 73.19% COD was also recorded. These findings demonstrated the potential to cultivate microalgae and extract biomolecules for commercial purposes. Full article
(This article belongs to the Section Wastewater Treatment and Reuse)
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22 pages, 8862 KiB  
Article
Research on Sudden Unbalance Response of Rigid-Elastic-Oil Coupled Ball Bearings
by Yan Li, Yongcun Cui and Sier Deng
Lubricants 2024, 12(5), 161; https://doi.org/10.3390/lubricants12050161 (registering DOI) - 06 May 2024
Abstract
(1) Background: To better understand the dynamic characteristics of a ball bearing with an elastic ring squeeze film damper (ERSFD) under sudden unbalance, a novel dynamic model was established by fully considering the coupling between the ERSFD, bearing outer ring (the journal), rotor, [...] Read more.
(1) Background: To better understand the dynamic characteristics of a ball bearing with an elastic ring squeeze film damper (ERSFD) under sudden unbalance, a novel dynamic model was established by fully considering the coupling between the ERSFD, bearing outer ring (the journal), rotor, and disc (loading bearing); (2) Methods: An improved secant method was developed to determine the initial eccentricity values of the bearing’s outer ring and the disc. The dynamic response of the outer ring under different speed ratios, damping ratios, and mass ratios was solved using the variable-step Runge–Kutta method; (3) Results: In comparison, a low-speed ratio, high damping ratio, and low mass ratio were more conducive to suppressing the bearing vibration. When the imbalance was suddenly introduced, the displacement amplitude of the eccentricity, transmissibility, amplitude–frequency response, and the radius of the outer ring center locus increased; (4) Conclusions: This work provides a reference for further studying the nonlinear vibration of rolling bearings coupled with an ERSFD. Full article
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23 pages, 4224 KiB  
Article
Assessing the Water Footprints (WFPs) of Agricultural Products across Arid Regions: Insights and Implications for Sustainable Farming
by Saeed Sharafi, Mohammad Javad Nahvinia and Fatemeh Salehi
Water 2024, 16(9), 1311; https://doi.org/10.3390/w16091311 (registering DOI) - 06 May 2024
Abstract
Water resource management has emerged as a pivotal concern within arid regions in recent times. The water footprint (WFP) index stands out as a principal gauge for facilitating comprehensive watershed management. This study endeavors to compute the WFP of diverse agricultural products encompassing [...] Read more.
Water resource management has emerged as a pivotal concern within arid regions in recent times. The water footprint (WFP) index stands out as a principal gauge for facilitating comprehensive watershed management. This study endeavors to compute the WFP of diverse agricultural products encompassing major crops, orchards, cucurbits, and medicinal plants across arid regions. This research focuses on three distinct climate scenarios: the Shazand Plain with a semidry climate, the Khomein Plain characterized by a dry climate, and the Saveh Plain exhibiting a very dry climate. This study also seeks to ascertain the climate most conducive to cultivating crops from a WFP (green, blue, and gray) perspective. To achieve these objectives, this study employed the CropWat family software to determine crop water requirements, as well as considering crop yield and relevant parameters for calculations. The findings of the investigation unveiled that the cultivated areas in the respective climates amounted to 19,479 ha (semidry), 18,166 ha (dry), and 41,682 ha (very dry). These areas were allocated as follows: 88%, 85%, and 55% for crops; 11%, 13%, and 40% for orchards; and 1%, 2%, and 5% for cucurbit crops. Importantly, the very dry climate was predisposed to allocating more land for low-water-demand orchards. Among the major crops, wheat occupied 44%, 39%, and 43% of the total areas in the semidry, dry, and very dry climates, respectively. Analyzing the overall agricultural output in these climates, it was revealed that over 79%, 69%, and 66% of production correlated with crops; 17%, 19%, and 22% with orchards; and 4%, 12%, and 12% with cucurbits, respectively. In terms of water consumption, maize and apples emerged as the highest performers, with varying consumption patterns across different crops. Interestingly, canola exhibited a substantially higher WFP, surpassing wheat and barley by 56.48% and 58.85%, respectively, in dry climates. Cucurbit crops, on the other hand, displayed a lower WFP in dry climates, which could potentially encourage their cultivation. The influence of climate warming on canola’s WFPgray introduced complexity, challenging the conventional correlation between WFP and yields. Medicinal plants consistently demonstrated lower WFP values, underscoring the need for deliberate and considerate cultivation decisions in this regard. Full article
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18 pages, 5907 KiB  
Article
Influence of Nanoparticles in Lubricant on Sliding Contact of Atomic Rough Surfaces—A Molecular Dynamics Study
by Xuan Zheng, Lihong Su and Guanyu Deng
Lubricants 2024, 12(5), 160; https://doi.org/10.3390/lubricants12050160 (registering DOI) - 06 May 2024
Abstract
In this work, large-scale molecular dynamics (MD) computational simulations were performed in order to explore the sliding contact responses of rough surfaces with hexadecane lubricant and added nanoparticles. Simulation results revealed that the frictional state was dependent on the fluid, nanoparticle, and surface [...] Read more.
In this work, large-scale molecular dynamics (MD) computational simulations were performed in order to explore the sliding contact responses of rough surfaces with hexadecane lubricant and added nanoparticles. Simulation results revealed that the frictional state was dependent on the fluid, nanoparticle, and surface roughness. Three lubricating conditions were compared based on considerations of different amounts of fluid molecules. The lubricant was not able to separate the frictional contact surfaces if the quantity of lubricant molecules was insufficient. Particularly, there were no lubricating contributions when the amount of lubricant was too low, and the lubricant therefore only filled the pits in the surface roughness. Thus, the normal load was primarily supported by the contact between the two surfaces and nanoparticles, leading to significant surface morphology changes. In contrast, the frictional contact surfaces were able to be completely separated by the lubricant when there was a sufficient amount of fluid, and a very good lubricating effect could thus be achieved, resulting in a smaller friction force. In addition, the changes in surface morphology, contact area, and RMS are discussed in this paper, in order to reveal the dynamic frictional process. Full article
(This article belongs to the Special Issue Frictional and Wear Behaviors of Sliding Interfaces across Scales)
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16 pages, 5551 KiB  
Article
Treatment of Pickle Wastewater under Varying Salinity Conditions within the Sequencing Batch Biofilm Reactor System
by Nuonan Shen, Hongyun Guo, Tingting Yao, Li Xu, Youxian Gao and Ping Yang
Water 2024, 16(9), 1312; https://doi.org/10.3390/w16091312 (registering DOI) - 06 May 2024
Abstract
Pickle wastewater is a highly saline organic effluent that poses a significant ecological risk. In this study, a sequencing batch biofilm reactor (SBBR) was used to treat such wastewater, and a denitrification system capable of simultaneously removing high levels of nitrogen and organic [...] Read more.
Pickle wastewater is a highly saline organic effluent that poses a significant ecological risk. In this study, a sequencing batch biofilm reactor (SBBR) was used to treat such wastewater, and a denitrification system capable of simultaneously removing high levels of nitrogen and organic matter was successfully established. Through salinity incremental increase, the system operated stably, and the removal rates of COD, TN, and NH4+-N could be maintained at about 96%, 93%, and 99% under the salinity of 3.0%. The effect of salinity on the structure and function of microbial communities in the reactor was investigated by high-throughput sequencing. The results showed that increasing salinity could reduce the diversity, change the structure, and reduce the functionality of the microbial community. Under high-salt conditions (salt content of 3.0%), salt-tolerant microorganisms such as Actinobacteriota became dominant populations. As salinity increased, NOB (nitrite oxidizing bacteria) was strongly inhibited, and its abundance decreased rapidly until it disappeared. Partial nitrification–denitrification (PND) gradually became the main denitrification pathway. In conclusion, this experiment not only shows that SBBR treatment of pickle wastewater has strong feasibility, but also provides a theoretical research basis for the engineering treatment of pickle wastewater. Full article
(This article belongs to the Section Wastewater Treatment and Reuse)
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17 pages, 3685 KiB  
Article
Cleansing Tannery Effluent with Pleurotus opuntiae: A Green Solution for Environmental Restoration and Toxicity Evaluation
by Priyanka Yadav, Vartika Mishra, Tejmani Kumar, Umesh Kumar Singh, Emanuel Vamanu and Mohan Prasad Singh
Water 2024, 16(9), 1313; https://doi.org/10.3390/w16091313 (registering DOI) - 06 May 2024
Abstract
Heavy metal contamination has emerged as a global environmental concern, with tannery effluents serving as a significant source of these pollutants. The discharge of tannery effluents (TEs) into natural ecosystems has given rise to a spectrum of catastrophic risks, exacerbating concerns related to [...] Read more.
Heavy metal contamination has emerged as a global environmental concern, with tannery effluents serving as a significant source of these pollutants. The discharge of tannery effluents (TEs) into natural ecosystems has given rise to a spectrum of catastrophic risks, exacerbating concerns related to public health, safety, and environmental integrity. This current study focuses on the mycoremediation of the heavy metals present in TE, employing the mycelia of Pleurotus opuntiae, an environmentally sustainable solution. The toxicity of TE was rigorously characterized by evaluating a range of physicochemical parameters in accordance with the American Standard and Testing Methods. Subsequently, various diluted concentrations of effluent (25%, 50%, 75% and 100%) were incorporated into MDA media to assess the tolerance index (TI) of P. opuntiae. Notably, the highest TI was observed in the 25% and 50% TE concentrations, while no growth was observed in the 75% and 100% groups due to the exceptionally elevated heavy metal content. P. opuntiae demonstrated remarkable efficacy in heavy metal removal, with the most substantial reductions recorded in the 25% diluted effluent (91.3% Pb, 72.2% Cr and 66.5% Zn), closely followed by the 50% diluted effluent. The highest intracellular bioaccumulation was observed for Pb (17.2 µg/g), outperforming Cr (14.5 µg/g) and Zn (8.5 µg/g) in mycelia grown in 25% diluted effluent. To elucidate the detoxification mechanisms underlying metal removal, various characterizations of the mycelium were conducted, including SEM, FTIR, and XRD analyses. Furthermore, LC–MS analysis shed light on the pivotal role of metabolites in regulating heavy metals within the physiological metabolism of P. opuntiae. Moreover, an upsurge in the concentration of the stress marker, metallothionein, and augmented activity of antioxidant enzymes, like SOD, CAT, LPO and GSH, collectively suggested the significant role of antioxidants in mitigating reactive oxygen species (ROS) and heavy metal toxicity. These comprehensive findings provide a solid foundation for understanding the mechanisms responsible for heavy metal removal by P. opuntiae and pave the way for the development of effective remediation strategies for decontaminating the effluents discharged by the leather industry, contributing to the preservation of our environment and to public well-being. Full article
(This article belongs to the Section Wastewater Treatment and Reuse)
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