bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Analysis of Environmental and Economic Performance of Agricultural Cooperatives and Smallholder Farmers for Apple Production in China
Authors: Cheng Juanjuan , Wang Qian , Li Dongjian , Yu Jin
Published: August 2022

China is the world’s largest apple producer, and agricultural cooperatives play an important role in promoting sustainable production in its whole life cycle system. However, few studies on cooperatives have evaluated the environmental and economic performance from the life cycle thinking perspective. In this study, the combined methods of life cycle assessment (LCA) and life cycle cost (LCC) were used to comparatively analyze the environmental and economic performance of apple production between cooperatives and smallholder farmers. The results showed that, compared to the smallholder farmers, cooperatives significantly reduced resource depletion and environmental impacts by 12.50–22.16% in each category. The total environmental index for the cooperatives was 7.44% and 22.09% lower than smallholder farmers; meanwhile, the total LCC was 2659.71 Chinese Yuan (CNY), 19.27% lower than smallholder farmers. However, the net profit was 2990.29 CNY for the cooperatives, 21.23% higher than smallholder farmers. The results indicated that cooperatives exhibited a higher net profit while having lower resource input, environmental impact, and LCC than smallholder farmers. Moreover, pesticides and fertilizers were identified as the most critical environmental hotspots. Moreover, human labor cost was the most significant contributor to the total economic cost of the apple production system. These findings provide insights into optimizing farm inputs for apple production and active participation in agricultural cooperatives to alleviate multiple environmental impacts while maintaining apple yield and improving economic benefits, intending to make a marginal contribution to promoting sustainable development of the apple industry in China.
Genome-Wide Identification of GASA Gene Family in Ten Cucurbitaceae Species and Expression Analysis in Cucumber
Authors: Zhang Kaijing , Hu Yuchao , Yang Dekun , Yan Congsheng , Li Nanyang , Li Ziang , Njogu Martin Kagiki , Wang Xing , Jia Li
Published: August 2022

Gibberellic acid-stimulated in Arabidopsis (GASA), a unique small molecular protein of plants, plays an essential role in plant growth and development. The GASA family genes have been identified and studied in many plants. However, the identification of GASA gene family in Cucurbitaceae species has not been reported yet. Therefore, in this study, based on the available genome information on the Cucurbitaceae species, the GASA family genes in 10 Cucurbitaceae species including cucumber (Cucumis sativus), watermelon (Citrullus lanatus), melon (Cucumis melo), pumpkin (Cucurbita moschata), wax gourd (Benincasa hispida), sponge gourd (Luffa cylindrica), bottle gourd (Lagenaria siceraria), bitter gourd (Momordica charantia), chayote (Sechium edule), and snake gourd (Trichosanthes anguina) were identified with bioinformatics methods. To understand the molecular functions of GASA genes, the expression pattern analysis of cucumber GASA family genes in different tissues and stress responses were also analyzed. The results showed that a total of 114 GASA genes were identified in the 10 Cucurbitaceae species, which were divided into three subfamilies. Synteny analysis of GASA genes among cucumber, Arabidopsis and rice showed that nine cucumber GASA genes were colinear with 12 Arabidopsis GASA genes, and six cucumber GASA genes were colinear with six rice GASA genes. The cis-acting elements analysis implied that the cucumber GASA genes contained many cis-elements associated with stress and hormone response. Tissue-specific expression analysis of cucumber GASA family genes revealed that only the CsaV3_2G029490 gene was lowly or not expressed in all tissues, the CsaV3_3G041480 gene was highly expressed in all tissues, and the other seven GASA genes showed tissue-specific expression patterns. Furthermore, nine cucumber GASA family genes exhibited different degrees of regulatory response under GA, abiotic and biotic stresses. Two cucumber GASA genes, CsaV3_3G042060 and CsaV3_3G041480, were differentially expressed under multiple biotic and abiotic stresses, which indicated that these two GASA genes play important roles in the growth and development of cucumber.
Global Sensitivity Analysis of Key Parameters in the APSIMX-Sugarcane Model to Evaluate Nitrate Balance via Treed Gaussian Process
Authors: Rathnappriya R. H. K. , Sakai Kazuhito , Okamoto Ken , Kimura Sho , Haraguchi Tomokazu , Nakandakari Tamotsu , Setouchi Hideki , Bandara W. B. M. A. C.
Published: August 2022

Difficulties in direct monitoring of nitrate balance in agricultural fields reveal the importance of modeling and quantifying the affecting parameters on nitrate balance. We constructed meta-models for APSIMX-Sugarcane using the treed gaussian process and conducted a global sensitivity analysis for nitrate uptake and leaching under three conditions: (1) bare land (BL) to examine the influence of soil hydraulic characteristics, (2) N-free treatment under radiation use efficiency (RUE) ranges (i) 1.2–1.8 [N-free(a)] and (ii) 1.8–2.5 [N-free(b)], and (3) urea conditions to examine the influence of plant growth. Generated meta-models showed good accuracy (for all conditions: R2 > 0.70; NRMSE < 16%; AI > 0.90). The most influential parameters (sensitivity indices ≥ 0.02) were as follows: for leached NO3−N in BL: the parameter rerated to saturated flow-proportion of water between saturation and field capacity (SWCON) of all soil layers; for NO3− uptake and leached NO3−N in N-free(a) and urea: RUE of the phenological stage (PS) 3 (RUE3) and 4, tt_emerg_to_begcane, green_leaf_no, and y_n_conc_crit_leaf of PS 4 (NCL4); in N-free(b): RUE3, NCL4, and SWCON of soil layers 0–15 cm; 15–30 cm, which confirmed that influential parameters were depended on N-stress. The outcomes of this study are useful for enhancing the accuracy and efficiency of crop modeling.
Irrigation Method and Volume for Korla Fragrant Pear: Impact on Soil Water and Salinity, Yield, and Fruit Quality
Authors: Zhang Yao , Liu Hongguang , Gong Ping , He Xinlin , Wang Jiaxin , Wang Zonglan , Zhang Jingrui
Published: August 2022

A field study in an orchard of Korla fragrant pear tested three levels of irrigation (as varying proportions of evapotranspiration; namely, W1: 70% ETC, W2: 85% ETC, and W3: 100% ETC) and four methods of applying such irrigation; namely, F1: surface drip, F2: subsurface, F3: root zone infiltration, and CK: flood irrigation (as the control or check). The effects of the different treatments were evaluated in terms of plant growth (shoot length and leaf area), fruit yield and quality, and the distribution of water and salt in soil. For a given method of irrigation, soil moisture content, wet-front displacement, the length of new shoots, and leaf area under W3 were significantly higher than those under W1 and W2. The salt content under W3 was also significantly lower than that under W1 and W2, whereas the yield was significantly higher—by 5.89–13.85% compared to that under W2 and by 4.08–13.13% compared to that under W1. For a given volume of irrigation, yield, water-use efficiency, and fruit quality were significantly higher under F3 and F2 than those under F1. Soil water was more uniformly distributed and its content was significantly higher under F3 than the corresponding values under F1 or F2. The salt content of the root zone was the lowest under F3, and most of the soil salt was in soil layers deeper than 80 cm, but there was no significant difference between F3 and F2 (p < 0.05). There were also no significant differences in shoot length and leaf area among the three irrigation methods (F1, F2, and F3) (p < 0.05). Compared to that under F1, root zone infiltration under W1 was 3.61% greater, that under W2 was 6.58% greater, and that under W3 was 5.43% greater. The irrigation water-use efficiency and production factor efficiency for nitrogen under F3 and F2 were significantly higher than those under F1 (p < 0.05). Principal component analysis showed that the comprehensive score for fruit quality under different volumes of irrigation was the highest under W3, was intermediate under W2, and was the lowest under W1. The corresponding ranking of different irrigation methods was F2, F3, F1, and CK. Comprehensive analysis showed that yield, quality, and the efficiency of utilization of water and fertilizer were higher under the combination W3F3 than under any other combination—therefore, irrigation at 100% of evapotranspiration applied through root zone infiltration is recommended for Korla fragrant pear. The research results can provide a theoretical basis for the optimal use of water and for salt control in pear in Korla, Xinjiang.
Compatible Graft Establishment in Fruit Trees and Its Potential Markers
Authors: Adhikari Prakash Babu , Xu Qiang , Notaguchi Michitaka
Published: August 2022

Plant grafting is a maneuver humans learned from nature and has been practiced since ancient times. The technique has long been applied for efficient propagation as well as for the modification of the traits of interest, such as stress tolerance, tree size, and fruit quality. Since grafting can enhance the environmental tolerance and disease resistance of a plant, its techniques are now used not only in tree species but also among vegetables. Despite such wide advantages of grafting, however, the potential cause behind a compatible graft establishment (scion-rootstock connection) is yet to be fully understood. As compared to succulent herbaceous plants, woody plants often take a longer time for the graft-take and the plants may exhibit incompatible/unsuccessful graft-establishment symptoms within a period ranging from months to years. In this review, we discuss factors involved in a successful/compatible graft establishment along with bottlenecks of our understanding and future perspectives in a simplified manner- particularly focusing on incompatible graft formation on fruit trees based on earlier studies in the field.
Identification of Genes Associated with Crest Cushion Development in the Chinese Crested Duck
Authors: Guo Qixin , Huang Lan , Jiang Yong , Wang Zhixiu , Chen Guohong , Bai Hao , Chang Guobin
Published: August 2022

The crest trait is a specific and widely distributed phenotype in birds. However, the shape and function vary in different species of birds. To understand the mechanism of crest formation, the present study used RNA sequencing and weighted gene co-expression network analysis (WGCNA) to identify the crest-cushion-associated genes in the Chinese crested (CC) duck. As a result, 28, 40, 32, 33, and 126 differentially expressed genes (DEGs) were identified between CC and cherry valley (CV) ducks at the embryonic days (E)15, E22, E28, D7 (7 days old), and D42 stages, respectively. In addition, the results of WGCNA show that 3697 (turquoise module), 485 (green-yellow module), 687 (brown module), 205 (red module), and 1070 (yellow module) hub genes were identified in the E15, E22, E28, D7, and D42 stages, respectively. Based on the results of DEGs and WGCNA Venn analysis, three, two, zero, one, and seven genes were found to be associated with crest cushion formation at the E15, E22, E28, D7, and D42 stages, respectively. The expression of all the associated genes and some DEGs was verified by real-time quantitative polymerase chain reaction. In conclusion, this study provided an approach revealing the molecular mechanisms underlying the crested trait development.
“Emotional Proximity” and “Spatial Proximity”: Higher Relationship Quality and Nearer Distance Both Strengthen Scratch Contagion in Tibetan Macaques
Authors: Zhang Yu-Heng , Wang Xi , Chen Meng-Meng , Tai Yi-Mei , Li Jin-Hua
Published: August 2022

Behavioral contagion has been defined as a phenomenon in which an unlearned behavior automatically triggers a similar behavior in others. Previous studies showed that a behavioral contagion might have the function of strengthening social relationships, promoting group coordination and maintaining social cohesion. However, so far, there are few studies investigating the correlation between contagious scratching and social bonding. Tibetan macaques (Macaca thibetana) live in multi-male and multi-female cohesive matrilineal groups, and scratching is usually observed in their affiliated interactions. We investigated the process of scratch contagion in one group of free-ranging Tibetan macaques and explored whether behavioral contagion could consolidate social relationships and maintain social stability. Results showed that the scratching was contagious and correlated with relationship quality and spatial distance. In dyads with a higher Dyadic Composite Sociality Index (DSI), the contagion was strong. In addition, contagions occurred more frequently and faster among individuals nearer to each other. In terms of social groups, members with higher social centrality participated in more behavioral contagion, whether as expressers or observers. Our findings provide new perspectives for studying behavioral contagions in humans and animals.
Peste des Petits Ruminants (PPR) Vaccination Cost Estimates in Burkina Faso
Authors: Ilboudo Guy Sidwatta , Kane Papa Abdoulaye , Kotchofa Pacem , Okoth Edward , Maiga Adama , Dione Michel
Published: August 2022

Every year the government organizes country-wide vaccination campaigns targeting peste des petits ruminants (PPR) for small ruminants (sheep and goats). Despite the heavy investment in vaccination, no study has either rigorously estimated or described the cost of vaccine delivery. This study aimed to fill this gap by assessing and describing the cost of delivery of vaccines against PPR using the 2020 vaccination campaign data. The microcosting approach based on the World Health Organization (WHO) guidelines to construct comprehensive multiyear plans (cMYP) for human immunization programs was used. The cost data is presented for the public and private vaccine delivery channels separately and analyzed using three approaches considering activity lines, inputs, and nature of cost (fixed versus variable). Results show that the unit cost of vaccinating a sheep or goat is estimated at XOF 169 (USD 0.3) and XOF 103 (USD 0.18) through the public and private channels, respectively. Using the activity line framework, we found that the field activities including charges for vaccinator, cost of vaccination materials, and field transportation account for more than 50% of the vaccination cost. In terms of inputs, the personnel cost is the most significant contributor with 65%. Fixed costs are higher in the public sector with up to 46% compared to the private sector which is estimated to take 26% of the cost. This study informs veterinary services’ investment decision options for a better allocation of resources in implementing PPR and other small ruminant disease control efforts in Burkina Faso and the Sahel.
Yeast β-Glucans as Fish Immunomodulators: A Review
Authors: Machuca Cristian , Méndez-Martínez Yuniel , Reyes-Becerril Martha , Angulo Carlos
Published: August 2022

Administration of immunostimulants in fish is a preventive method to combat infections. A wide variety of these biological molecules exist, among which one of the yeast wall compounds stands out for its different biological activities. The β-glucan that forms the structural part of yeast is capable of generating immune activity in fish by cell receptor recognition. The most frequently used β-glucans for the study of mechanisms of action are those of commercial origin, with doses recommended by the manufacturer. Nevertheless, their immune activity is inefficient in some fish species, and increasing the dose may show adverse effects, including immunosuppression. Conversely, experimental β-glucans from other yeast species show different activities, such as antibacterial, antioxidant, healing, and stress tolerance properties. Therefore, this review analyses the most recent scientific reports on the use of yeast β-glucans in freshwater and marine fish.
Low Flow versus No Flow: Ischaemia Reperfusion Injury Following Different Experimental Models in the Equine Small Intestine
Authors: Grages Anna Marei , Verhaar Nicole , Pfarrer Christiane , Breves Gerhard , Burmester Marion , Neudeck Stephan , Kästner Sabine
Published: August 2022

In experimental studies investigating strangulating intestinal lesions in horses, different ischaemia models have been used with diverging results. Therefore, the aim was to comparatively describe ischaemia reperfusion injury (IRI) in a low flow (LF) and no flow (NF) model. Under general anaesthesia, 120 min of jejunal ischaemia followed by 120 min of reperfusion was induced in 14 warmbloods. During ischaemia, blood flow was reduced by 80% (LF, n = 7) or by 100% (NF, n = 7). Intestinal blood flow and oxygen saturation were measured by Laser Doppler fluxmetry and spectrophotometry. Clinical, histological, immunohistochemical and Ussing chamber analyses were performed on intestinal samples collected hourly. Tissue oxygen saturation was significantly lower in NF ischaemia. The LF group exhibited high variability in oxygen saturation and mucosal damage. Histologically, more haemorrhage was found in the LF group at all time points. Cleaved-caspase-3 and calprotectin-stained cells increased during reperfusion in both groups. After NF ischaemia, the tissue conductance was significantly higher during reperfusion. These results aid in the selection of suitable experimental models for future studies. Although the LF model has been suggested to be more representative for clinical strangulating small intestinal disease, the NF model produced more consistent IRI.
Anticalin N- or C-Terminal on a Monoclonal Antibody Affects Both Production and In Vitro Functionality
Authors: Aubrey Nicolas , Gouilleux-Gruart Valérie , Dhommée Christine , Mariot Julie , Boursin Fanny , Albrecht Nicolas , Bergua Cécile , Croix Cécile , Gilotin Mäelle , Haudebourg Eloi , Horiot Catherine , Matthias Laetitia , Mouline Caroline , Lajoie Laurie , Munos Audrey , Ferry Gilles , Viaud-Massuard Marie-Claude , Thibault Gilles , Velge-Roussel Florence
Published: August 2022

Bispecific antibodies (BsAbs) represent an important advance in innovative therapeutic strategies. Among the countless formats of BsAbs, fusion with molecules such as anticalins linked to a monoclonal antibody (mAb), represents an easy and low-cost way to obtain innovative molecules. We fused an anticalin against human fibronectin to a molecule biosimilar to trastuzumab (H0) or rituximab (R0), in four different positions, two on the N terminal region of heavy or light chains and two on the C terminal region. The eight BsAbs (H family (HF) 1 to 4 and R family (RF) 1 to 4) were produced and their affinity parameters and functional properties evaluated. The presence of anticalin did not change the glycosylation of the BsAb, shape or yield. The antigenic recognition of each BsAb family, Her2 for HF1 to 4 and CD20 for RF1 to 4, was slightly decreased (HF) or absent (RF) for the anticalin N-terminal in the light chain position. The anticalin recognition of FN was slightly decreased for the HF family, but a dramatic decrease was observed for RF members with lowest affinity for RF1. Moreover, functional properties of Abs, such as CD16 activation of NK, CD32-dependent phagocytosis and FcRn transcytosis, confirmed that this anticalin position leads to less efficient BsAbs, more so for RF than HF molecules. Nevertheless, all BsAbs demonstrated affinities for CD16, CD32 and FcRn, which suggests that more than affinity for FcRs is needed for a functioning antibody. Our strategy using anticalin and Abs allows for rapid generation of BsAbs, but as suggested by our results, some positions of anticalins on Abs result in less functionality.
Incidence and Determinants of Piperacillin/Tazobactam-Associated Hypokalemia: A Retrospective Study
Authors: Seo Heenam , Kim Eunyoung
Published: August 2022

Piperacillin/tazobactam (TZP) is a commonly used antibiotic for treating moderate-to-severe infections because of its broad-spectrum activity and recommendation as an alternative to carbapenem. TZP-associated severe hypokalemia has been consistently reported; however, related studies are very rare. This study aimed to evaluate the incidence and risk factors of TZP-associated hypokalemia (TAH). A retrospective cohort study was conducted on hospitalized adult patients who received TZP from 1 January 2015 to 31 December 2017 at a tertiary teaching hospital. Of the 713 patients, 13.9% had TAH. As a result of multivariate logistic regression analysis, older age (OR 1.03, 95% CI: 1.02–1.05, p < 0.001), female sex (OR 1.88, 95% CI: 1.18–3.00, p = 0.008), longer duration of TZP therapy (OR 1.08, 95% CI: 1.04–1.13, p < 0.001), and higher TZP daily dose (OR 1.10, 95% CI: 1.01–1.20, p = 0.049) were independently associated with TAH. In contrast, higher baseline serum potassium level (OR 0.13, 95% CI: 0.07–0.26, p < 0.001) was related to lower TAH. Furthermore, hypokalemia mostly occurred in the early days of TZP therapy (median onset time: 4 days). Thus, close monitoring of serum potassium levels, especially upon therapy initiation, is essential to prevent TAH.
Uptake and Immunomodulatory Properties of Betanin, Vulgaxanthin I and Indicaxanthin towards Caco-2 Intestinal Cells
Authors: Wang Yunqing , Fernando Ganwarige Sumali N. , Sergeeva Natalia N. , Vagkidis Nikolaos , Chechik Victor , Do Thuy , Marshall Lisa J. , Boesch Christine
Published: August 2022

The present study aimed to compare the absorption and transport patterns of three main betalains, betanin, vulgaxanthin I and indicaxanthin, into intestinal epithelial cells and to assess their distinct molecular effects on inflammatory and redox-related cell signalling in association with their radial scavenging potencies. All three betalains showed anti-inflammatory effects (5–80 μM), reflected by attenuated transcription of pro-inflammatory mediators such as cyclooxygenase-2 and inducible NO-synthase. Concomitant increases in antioxidant enzymes such as heme oxygenase-1 were only observed for betanin. Moreover, betanin uniquely demonstrated a potent dose-dependent radical scavenging activity in EPR and cell-based assays. Results also indicated overall low permeability for the three betalains with Papp of 4.2–8.9 × 10−7 cm s−1. Higher absorption intensities of vulgaxanthin and indicaxanthin may be attributed to smaller molecular sizes and greater lipophilicity. In conclusion, betanin, vulgaxanthin I and indicaxanthin have differentially contributed to lowering inflammatory markers and mitigating oxidative stress, implying the potential to ameliorate inflammatory intestinal disease. Compared with two betaxanthins, the greater efficacy of betanin in scavenging radical and promoting antioxidant response might, to some extent, compensate for its poorer absorption efficiency, as demonstrated by the Caco-2 cell model.
Evaluation of Performance of Polyacrylamide-Modified Compacted Clay as a Gas Barrier: Water Retention and Gas Permeability and Diffusion Characteristics
Authors: Bi Yu-Zhang , Wen Jia-Ming , Wu Hao-Liang , Du Yan-Jun
Published: August 2022

In this paper, the performance of a gas barrier that consisted of polyacrylamide (PAM)-modified compacted clayey soil was experimentally explored. The moisture content and water loss characteristics of the tested soils were adopted as indicative indices of water retention capacity (WRC). The gas permeability (Kp) and gas diffusion coefficient (Dp) of the modified compacted clays were evaluated via gas permeability and gas diffusion tests. The test results showed that the moisture content of the modified compacted clay samples subjected to drying tests increased with increasing polyacrylamide content. Kp and Dp decreased with increasing PAM content. Compared with 0.2% PAM content, the Kp of the sample with 1.0% PAM was reduced by ten times, and the Dp was reduced to ~35%. Compared to the unmodified clay, the liquid limit of the PAM-modified clay increased by 45~55%. Comparison of the liquid limit tests between this study and previous studies revealed that the liquid limit ratio of the zwitterionic polyacrylamide (ZP)-modified soil was much higher than the other material-modified soils. The results of this study are useful to facilitate the application of modified compacted clays as gas barrier materials at industrial contaminated sites.
Hypertension Detection Based on Photoplethysmography Signal Morphology and Machine Learning Techniques
Authors: Evdochim Lucian , Dobrescu Dragoș , Halichidis Stela , Dobrescu Lidia , Stanciu Silviu
Published: August 2022

In our modern digitalized world, hypertension detection represents a key feature that enables self-monitoring of cardiovascular parameters, using a wide range of smart devices. Heart rate and blood oxygen saturation rate are some of the most important ones, easily computed by wearable products that are provided by the photoplethysmography (PPG) technique. Therefore, this low-cost technology has opened a new horizon for health monitoring in the last decade. Another important parameter is blood pressure, a major predictor for cardiovascular characterization and health related events. Analyzing only PPG signal morphology and combining the medical observation with machine learning (ML) techniques, this paper develops a hypertension diagnosis tool, named the ANC Test™. During the development process, distinguishable characteristics have been observed among certain waveforms and certain types of patients that leads to an increased confidence level of the algorithm. The test was enchanted by machine learning models to improve blood pressure class detection between systolic normotensive and hypertensive patients. A total of 359 individual recordings were manually selected to build reference signals using open-source available databases. During the development and testing phases, different ML models accuracy of detecting systolic hypertension scored in many cases around 70% with a maximum value of 72.9%. This was resulted from original waveform classification into four main classes with an easy-to-understand nomenclature. An important limitation during the recording processing phase was given by a different PPG acquisition standard among the consulted free available databases.
Rapid and Accurate PPA Prediction for the Template-Based Processor Design Methods
Authors: Tang Mingxin , Huang Libo , Chen Wei
Published: August 2022

The template-based chip design method aims to build rapidly. However, it still need synthesis and simulation flows to get the performance, power, and area (PPA) reports and find the proper parameters set in the design space exploration, which takes a long time. Therefore, a rapid and accurate PPA prediction method is proposed. At first, the PPA Prediction Model based on Multivariate Linear regression (ML-PM) is proposed to fit the multiple parameters’ influence on the PPA via the single parameter affection. Moreover, a Multivariate NonLinear regression Prediction Model (MNL-PM) based on Amdahl’s law is introduced to improve the accuracy of the PPA estimation. The empirical evaluation of the method shows that the PPA prediction for the template-based chip design methods can reach 98.60%, 99.19%, and 98.53% accuracy on performance, power, and, area separately, when compared with the PPA generated via the synthesis and simulation flows.
A Mixing Process Influenced by Wall Jet-Induced Shock Waves in Supersonic Flow
Authors: Zhang Ji , Yang Daoning , Wang Yi , Zhang Dongdong
Published: August 2022

With the development of hypersonic air-breathing propulsion systems, such as the supersonic combustion ramjet (Scramjet) and rocket-based combined cycle (RBCC) engines, the mixing process of supersonic airstream with fuel in the engine combustor has been drawing more and more attention. Due to the compressibility effects, the mixing process in a supersonic condition is significantly inhibited. In the present paper, the novel strategy of wall-jet induced shock waves (WJISW) is put forward to realize mixing enhancement. The interaction process between WJISW and the supersonic mixing layer is researched and the enhanced-mixing mechanism is revealed, employing large eddy simulation (LES) methods. The fine vortex structures of the flow field are well captured and presented, utilizing the numerical schlieren technique. Detailed visualization results indicate that WJISW in a low frequency condition can result in the ‘region action mode’ (RAM) never reported before. The drastic dynamic behaviors including growth, deformation, and distortion in the interaction region can undoubtedly promote the mixing of upper and lower streams. The Reynolds stress distributions along the streamwise x-direction suggest that more intense fluctuations can be achieved with a low frequency WJISW. Moreover, a sharp increase in mixing layer thickness can be realized in the interaction region. The dynamic mode decomposition (DMD) analysis results show that the mixing layer evolution process is dominated by the mode induced by WJISW, which leads to the coexistence of both large- and small-scale structures in the flow field. The entrainment process corresponding to large-scale vortices and the nibbling process corresponding to small-scale vortices can obviously promote mixing enhancement. It is suggested that the present proposed strategy is a good candidate for enhanced-mixing with application to Scramjet and RBCC combustors.
Visual Servo Control of the Macro/Micro Manipulator with Base Vibration Suppression and Backlash Compensation
Authors: Zhang Yaowen , Liu Yechao , Xie Zongwu , Liu Yang , Cao Baoshi , Liu Hong
Published: August 2022

This study investigates the visual servo control of the space station macro/micro manipulator system. The proposed approach is based on the position-based eye-in-hand visual servo (PBVS) and takes advantage of the hardware sensors to overcome the macro manipulator’s base flexibility and joint backlash. First, a vibration suppression approach based on the reaction force feedback control is proposed, the deflection forces are measured by the six-axis force/torque sensor at the base of the micro-manipulator, and damping is injected into the flexible base in the closed-loop control to suppress the base vibration. Second, the small changes of joint backlash are compensated based on the macro manipulator joint angles sensor and converted to the desired motion of the payloads. Finally, PBVS with the lag correction is proposed, which is adequate for the precise positioning of large payloads with significant low-frequency oscillations. Ground micro-gravity experiment implementation is discussed, simulations and experiments are carried out based on the equivalent 3-DOF flexible base manipulator system and the macro/micro manipulator ground facilities, and results demonstrate the effectiveness of the proposed control algorithm.
Solving the Moment Amplification Factor of a Lateral Jet by the Unsteady Motion Experimental Method
Authors: Xue Fei , Zhang Yunlong , Cao Ning , Li Liugang
Published: August 2022

In this paper, unsteady motion tests of a lateral jet adjusting an air vehicle’s attitude are carried out. Curves of pitch moment amplification factors (KM) for a lateral jet versus angle of attack (α) are obtained using a wind tunnel free-flight test technique with a jet and data processing method. This new method overcomes the disadvantage of previous experiments that can study only one unsteady characteristic. The free-flight test technique in the proposed method ensures that the test model can be coupled in real-time with multiple parameters (unsteady flow caused by the jet, unsteady air vehicle aerodynamic force, and unsteady air vehicle motion). This approach simulates an actual air vehicle’s complete jet test process and ensures more authentic and reliable test results. In the new data processing method, continuous data curves are fitted to discrete data points, making it easier to convert the angular displacement versus time curve into the pitch moment versus α curve to obtain KM. The results show that when the pressure of the micro high-pressure gas cylinder is 2.0 MPa, KM is below 1, indicating that the lateral jet does not significantly promote the pitching moment. When the gas cylinder pressure is 4.0 MPa and the angle of attack is 5° < |α| < 16°, KM is greater than 1, and the lateral jet promotes the pitching moment. When 16° < |α| < 20°, KM is less than 1, and the lateral jet does not significantly contribute to the pitching moment. It was further found that KM decreases slowly with increasing α. When |α| > 30°, the influence of the jet on the pitching moment nearly disappears.
SRMANet: Toward an Interpretable Neural Network with Multi-Attention Mechanism for Gearbox Fault Diagnosis
Authors: Liu Siyuan , Huang Jinying , Ma Jiancheng , Luo Jia
Published: August 2022

Deep neural network (DNN), with the capacity for feature inference and nonlinear mapping, has demonstrated its effectiveness in end-to-end fault diagnosis. However, the intermediate learning process of the DNN architecture is invisible, making it an uninterpretable black-box model. In this paper, a stacked residual multi-attention network (SRMANet) is proposed as a means of feature extraction of vibration signals, and visualizing the model training process, designing Squeeze-excitation residual (SE-Res) blocks to obtain additive features with minimal redundancy and sparsity. This study recommends the use of the attention fusion unit to ensure the interpretability of the model and ultimately to obtain representative features. By feeding the output gradient of the attention layer back to the original signal, the key feature components in the time domain signal can be effectively captured. Finally, the interpretability, identification accuracy and adaptability of the model under different operating conditions are verified on 12 different fault tasks in the planetary gearbox.
Network Theory to Reveal Ionospheric Anomalies over North America and Australia
Authors: Zhivetiev Ilya V. , Yasyukevich Yury V.
Published: August 2022

There are significant challenges to model the ionosphere due to different anomalies, especially under the increasing requirements for precision level. We used network theory to construct an ionospheric network analysis based on the data of global ionospheric maps for the period from 1998 to 2015. The network approach revealed different domains in the ionosphere. Besides the well-known equatorial anomaly, we revealed two more essential areas with “anomalous” behavior in the total electron content (TEC). Both anomalies are located at mid-latitudes: the first over most of North America, and the second one over the southeast part of Australia and the adjacent part of the Indian Ocean. The revealed areas partly coincide with the winter anomaly regions. Our results demonstrate that complex ionosphere/magnetic field/neutral atmosphere interaction can result in atypical ionosphere dynamics in huge areas.
A Success Story in Controlling Sand and Dust Storms Hotspots in the Middle East
Authors: Al-Dousari Ali , Omar Ali , Al-Hemoud Ali , Aba Abdulaziz , Alrashedi Majid , Alrawi Mohamad , Rashki Alireza , Petrov Peter , Ahmed Modi , Al-Dousari Noor , Baloshi Omar , Jarba Meshael , Esmail Ala , Alsaleh Abeer , William Teena
Published: August 2022

Using 30 years of satellite observations, two sand and dust storms (SDS) source locations (hotspots) were detected on the southern side of the Mesopotamian Flood Plain. Around 40 million people in the region are affected by the two hotspots, including populations in Iraq, Iran, Kuwait, Saudi Arabia, Qatar, Bahrain, and Emirates. Both hotspots encompass roughly 8212 km2 and contribute 11% to 85% in 2005 and 2021, respectively, of the total SDS in the region. Dust physical (particle surface area and size percentages) and chemical (mineralogy, major and trace elements, and radionuclides) properties show close similarities between source and downwind samples during SDS originated solely from the two hotspots. Deposited dust size particles show a finning trend towards the north in the Middle East compared to the south. A comprehensive assessment of the chemical and physical properties of soil and dust samples was conducted as an essential step in developing and implementing a mitigation plan in order to establish a success story in reducing SDS, improving air quality, and benefiting the gulf countries and neighboring regions.
Temperature and Precipitation Bias Patterns in a Dynamical Downscaling Procedure over Europe during the Period 1951–2010
Authors: Stergiou Ioannis , Tagaris Efthimios , Sotiropoulou Rafaella-Eleni P.
Published: August 2022

The Weather Research and Forecasting (WRF) mesoscale meteorological model is used to dynamically downscale data from the Goddard Institute for Space Studies (GISS) atmospheric general circulation model (GCM) CMIP5 version (Model E2-R) over Europe at a 0.25° grid size resolution, for the period of 1951 to 2010. The model configuration is single nested with grid resolutions of 0.75° to 0.25°. Two 30-year datasets are produced for the periods of 1951–1980 and 1981–2010, representing the historic and current periods, respectively. Simulated changes in climate normals are estimated and compared against the change derived from the E-OBS gridded dataset at 0.25° spatial analysis. Results indicate that the model consistently underpredicts the temperature fluctuations observed across all subregions, indicative of a colder model climatology. Winter has the strongest bias of all seasons, with the northeastern part of the domain having the highest. This is largely due to the land–atmosphere interactions. Conversely, spring and summer have the lowest regional biases, owing to a combination of low snow cover (relative to winter) and milder radiation effects (as opposed to summer). Precipitation has a negative bias in most cases, regardless of the subregion analyzed, due to the physical mechanism employed and the topographic features of each region. Both the change in the number of days when the temperature exceeds 25 °C and the change in the number of days when precipitation exceeds 5 mm/day are captured by the model reasonably well, exhibiting similar characteristics with their counterpart means.
A Numerical Method for a Heat Conduction Model in a Double-Pane Window
Authors: Coronel Aníbal , Huancas Fernando , Lozada Esperanza , Tello Alex
Published: August 2022

In this article, we propose a one-dimensional heat conduction model for a double-pane window with a temperature-jump boundary condition and a thermal lagging interfacial effect condition between layers. We construct a second-order accurate finite difference scheme to solve the heat conduction problem. The designed scheme is mainly based on approximations satisfying the facts that all inner grid points has second-order temporal and spatial truncation errors, while at the boundary points and at inter-facial points has second-order temporal truncation error and first-order spatial truncation error, respectively. We prove that the finite difference scheme introduced is unconditionally stable, convergent, and has a rate of convergence two in space and time for the L∞-norm. Moreover, we give a numerical example to confirm our theoretical results.
Quantitative Measurement of Spinal Cerebrospinal Fluid by Cascade Artificial Intelligence Models in Patients with Spontaneous Intracranial Hypotension
Authors: Fu Jachih , Chai Jyh-Wen , Chen Po-Lin , Ding Yu-Wen , Chen Hung-Chieh
Published: August 2022

Cerebrospinal fluid (CSF) hypovolemia is the core of spontaneous intracranial hypotension (SIH). More than 1000 magnetic resonance myelography (MRM) images are required to evaluate each subject. An effective spinal CSF quantification method is needed. In this study, we proposed a cascade artificial intelligence (AI) model to automatically segment spinal CSF. From January 2014 to December 2019, patients with SIH and 12 healthy volunteers (HVs) were recruited. We evaluated the performance of AI models which combined object detection (YOLO v3) and semantic segmentation (U-net or U-net++). The network of performance was evaluated using intersection over union (IoU). The best AI model was used to quantify spinal CSF in patients. We obtained 25,603 slices of MRM images from 13 patients and 12 HVs. We divided the images into training, validation, and test datasets with a ratio of 4:1:5. The IoU of Cascade YOLO v3 plus U-net++ (0.9374) was the highest. Applying YOLO v3 plus U-net++ to another 13 SIH patients showed a significant decrease in the volume of spinal CSF measured (59.32 ± 10.94 mL) at disease onset compared to during their recovery stage (70.61 ± 15.31 mL). The cascade AI model provided a satisfactory performance with regard to the fully automatic segmentation of spinal CSF from MRM images. The spinal CSF volume obtained through its measurements could reflect a patient’s clinical status.
AIEgen-Peptide Bioprobes for the Imaging of Organelles
Authors: Chen Bochao , Yuan Haotong , Zhang Wei , Hu Jingjing , Lou Xiaoding , Xia Fan
Published: August 2022

Organelles are important subsystems of cells. The damage and inactivation of organelles are closely related to the occurrence of diseases. Organelles’ functional activity can be observed by fluorescence molecular tools. Nowadays, a series of aggregation-induced emission (AIE) bioprobes with organelles-targeting ability have emerged, showing great potential in visualizing the interactions between probes and different organelles. Among them, AIE luminogen (AIEgen)-based peptide bioprobes have attracted more and more attention from researchers due to their good biocompatibility and photostability and abundant diversity. In this review, we summarize the progress of AIEgen-peptide bioprobes in targeting organelles, including the cell membrane, nucleus, mitochondria, lysosomes and endoplasmic reticulum, in recent years. The structural characteristics and biological applications of these bioprobes are discussed, and the development prospect of this field is forecasted. It is hoped that this review will provide guidance for the development of AIEgen-peptide bioprobes at the organelles level and provide a reference for related biomedical research.
Synchro-Squeezed Adaptive Wavelet Transform-Based Optimized Multiple Analytical Mode Decomposition: Parameter Identification of Cable-Stayed Bridge under Earthquake Input
Authors: Qu Hongya , Chang An , Li Tiantian , Guan Zhongguo
Published: August 2022

Deriving critical parametric information from recorded signals for system identification is critical in structural health monitoring and damage detection, while the time-varying nature of most signals often requires significant processing efforts due to structural nonlinearity. In this study, synchro-squeezed adaptive wavelet transform-based optimized multiple analytical mode decomposition (SSAWT-oMAMD) is proposed. The SSAWT algorithm acts as the preprocessing algorithm for clear signal component separation, high temporal and frequency resolution, and accurate time–frequency representation. Optimized MAMD is then utilized for signal denoising, decomposition, and identification, with the help of AWT for bisecting frequency determination. The SSAWT-oMAMD is first verified by the analytical model of two Duffing systems, where clear separation of the two signals is presented and identification of complex time-varying stiffness is achieved with errors less than 2.9%. The algorithm is then applied to system identification of a cable-stayed bridge model subjected to earthquake loading. Based on both numerical and experimental results, the proposed method is effective in identifying the structural state and viscous damping coefficient.
A New Framework for Isolating Sensor Failures and Structural Damage in Noisy Environments Based on Stacked Gated Recurrent Unit Neural Networks
Authors: Liu Bo , Xu Qiang , Chen Jianyun , Li Jing , Wang Mingming
Published: August 2022

To address the problem of sensor faults and measurement noise being misinterpreted as structural damage in structural health monitoring (SHM), this paper proposes a new framework for distinguishing sensor faults and structural damage based on stacked gated recurrent neural networks (S-GRU NN) that considers measurement noise. In this framework, the sensor signal reconstruction model was constructed by learning and training the S-GRU NN. The sensor fault threshold was determined based on a statistical analysis of the response reconstruction error between the true and reconstruction values. The sensor fault and structural damage are then distinguished by the fact that the sensor fault is independent and the structural damage is global. The framework is compared with other isolation frameworks based on traditional deep learning models through numerical simulations of a three-span continuous beam and laboratory steel frame experiments. The results show that the S-GRU NN has better reconstruction effect and isolation performance of sensor faults and structural damage in noisy environment.
Application of the Hazardous Waste Vitreous Enamel Generated in the Production Process of Heating Devices as a Partial Replacement for Cement
Authors: Kragović Milan , Stojmenović Marija , Ristić Nenad , Milićević Sonja , Živković Sanja , Liu Shanke , Gulicovski Jelena
Published: August 2022

Solving problems with hazardous waste materials is of crucial importance today. In the presented study, the application of waste vitreous enamel as a cement replacement up to 30% in mortar and concrete production was investigated. The chemical and physical-chemical characterization of the starting material was performed, as well as a leaching test and physical-mechanical characterization of mortar and concrete mixes. Obtained results showed that, due to its chemical composition, the vitreous enamel used must be classified as hazardous waste. At the same time, it possesses pozzolanic properties and satisfies minimal criteria for use as a cement replacement. Testing mortars and concrete mixes indicate that waste vitreous enamel can be applied as a construction material for cement replacement in the maximal amount of 20%. The leaching test was performed in accordance with international standard EN 12457-2 on hardened mortar with a maximal cement replacement of 20%. The results showed that there was no significant release of toxic elements, i.e., that the practical application of hazardous waste vitreous enamel in the construction industry may be fully in line with environmental standards.
Improving Data-Driven Infrastructure Degradation Forecast Skill with Stepwise Asset Condition Prediction Models
Authors: Lamm Kurt R. , Delorit Justin D. , Grussing Michael N. , Schuldt Steven J.
Published: August 2022

Organizations with large facility and infrastructure portfolios have used asset management databases for over ten years to collect and standardize asset condition data. Decision makers use these data to predict asset degradation and expected service life, enabling prioritized maintenance, repair, and renovation actions that reduce asset life-cycle costs and achieve organizational objectives. However, these asset condition forecasts are calculated using standardized, self-correcting distribution models that rely on poorly-fit, continuous functions. This research presents four stepwise asset condition forecast models that utilize historical asset inspection data to improve prediction accuracy: (1) Slope, (2) Weighted Slope, (3) Condition-Intelligent Weighted Slope, and (4) Nearest Neighbor. Model performance was evaluated against BUILDER SMS, the industry-standard asset management database, using data for five roof types on 8549 facilities across 61 U.S. military bases within the United States. The stepwise Weighted Slope model more accurately predicted asset degradation 92% of the time, as compared to the industry standard’s continuous self-correcting prediction model. These results suggest that using historical condition data, alongside or in-place of manufacturer expected service life, may increase the accuracy of degradation and failure prediction models. Additionally, as data quantity increases over time, the models presented are expected to improve prediction skills. The resulting improvements in forecasting enable decision makers to manage facility assets more proactively and achieve better returns on facility investments.