Active fault-tolerant control for the dual-valve hydraulic system with unknown dead-zone.

This paper proposes a method for high-performance motion control of the dual-valve hydraulic system subject to parameter and model uncertainties, unknown proportional valve dead-zone, and servo valve fault. By constructing a detailed dual-valve fault system model (DFSM), a disturbance observer-based adaptive robust fault-tolerant controller is proposed via the backstepping method. This controller integrates a model-based fault detection algorithm for real-time fault monitoring and subsequent controller reconfiguration. Additionally, the DFSM-based adaptive robust control (ARC) technique is applied to handle the unknown dead-zone problem and other nonlinearities, ensuring precise control. Once the servo valve fault occurs, a nonlinear observer estimates the fault and collaborates with the ARC to establish a reconfigured controller, thereby maintaining motion control. The effectiveness of the proposed method has been experimentally verified.

Utilizing ANN for Predicting the Cauchy Stress and Lateral Stretch of Random Elastomeric Foams under Uniaxial Loading.

As a result of their cell structures, elastomeric foams exhibit high compressibility and are frequently used as buffer cushions in energy absorption. Foam pads between two surfaces typically withstand uniaxial loads. In this paper, we considered the effects of porosity and cell size on the mechanical behavior of random elastomeric foams, and proposed a constitutive model based on an artificial neural network (ANN). Uniform cell size distribution was used to represent monodisperse foam. The constitutive relationship between Cauchy stress and the four input variables of axial stretch λU, lateral stretch λL, porosity φ, and cell size θ was given by con-ANN. The mechanical responses of 500 different foam structures (20% < φ < 60%, 0.1 mm < θ < 0.5 mm) under compression and tension loads (0.4 < λU < 3) were simulated, and a dataset containing 100,000 samples was constructed. We also introduced a pre-ANN to predict lateral stretch to address the issue of missing lateral strain data in practical applications. By combining physical experience, we chose appropriate input forms and activation functions to improve ANN's extrapolation capability. The results showed that pre-ANN and con-ANN could provide reasonable predictions for λU outside the dataset. We can obtain accurate lateral stretch and axial stress predictions from two ANNs. The porosity affects the stress and λL, while the cell size only affects the stress during foam compression.

Effect of Modified Magnesium Oxide on the Properties of Magnesium Phosphate Cement under a Negative Temperature Environment.

As a rapid repair material, magnesium phosphate cement (MPC) can be used under various environmental temperature conditions, but different temperatures significantly impact its strength and working performance. In this study, based on the surface modification of magnesium oxide, the working and mechanical properties of samples were investigated at an ambient temperature of -5 °C, and the hydration properties and microstructure of MPC were investigated using X-ray diffraction (XRD), thermogravimetric analysis (TG), mercury-in-pressure (MIP), and scanning electron microscopy (SEM). The results show that the modified magnesium oxide at a negative temperature prolongs the setting time of MPC from 10 min to more than 30 min, and fluidity can still be maintained or increased after half an hour. From 1 d to 28 d, the compressive strength growth rate of the reference group was 257.0% compared to 723.8% for the 10 wt% water-glass-modified MgO sample. K-struvite transformed from a blocky growth to a needle-like growth with the modified sample filling the pores and cracks inside the matrix. Compared with the unmodified sample, MPC's porosity decreased from 9.62% to 9.23% for 10 wt% water-glass-modified MgO. Therefore, the surface modification of magnesium oxide not only prolonged the setting time but also further benefited mechanical performance, which provides the prerequisites for MPC construction in negative-temperature environments.

Effect of Waste Glass on the Properties and Microstructure of Magnesium Potassium Phosphate Cement.

Waste glass is a bulk solid waste, and its utilization is of great consequence for environmental protection; the application of waste glass to magnesium phosphate cement can also play a prominent role in its recycling. The purpose of this study is to evaluate the effect of glass powder (GP) on the mechanical and working properties of magnesium potassium phosphate cement (MKPC). Moreover, a 40mm × 40mm × 40mm mold was used in this experiment, the workability, setting time, strength, hydration heat release, porosity, and microstructure of the specimens were evaluated. The results indicated that the addition of glass powder prolonged the setting time of MKPC, reduced the workability of the matrix, and effectively lowered the hydration heat of the MKPC. Compared to an M/P ratio (MgO/KH2PO4 mass ratio) of 1:1, the workability of the MKPC with M/P ratios of 2:1 and 3:1 was reduced by 1% and 2.1%, respectively, and the peak hydration temperatures were reduced by 0.5% and 14.6%, respectively. The compressive strength of MKPC increased with an increase in the glass powder content at the M/P ratio of 1:1, and the addition of glass powder reduced the porosity of the matrix, effectively increased the yield of struvite-K, and affected the morphology of the hydration products. With an increase in the M/P ratio, the struvite-K content decreased, many tiny pores were more prevalent on the surface of the matrix, and the bonding integrity between the MKPC was weakened, thereby reducing the compressive strength of the matrix. At less than 40 wt.% glass powder content, the performance of MKPC improved at an M/P ratio of 1:1. In general, the addition of glass powders improved the mechanical properties of MKPC and reduced the heat of hydration.

Effect of Cr (III) on hydration, microstructure of magnesium phosphate cement, and leaching toxicity evaluation.

The pollution caused by chromium and its compounds has caused severe harm to the environment, and waste stabilization/solidification containing these contaminants by magnesium phosphate cement (MPC) is one of the best ways to address this problem. If the mechanism between Cr3+ and MPC can be understood, it will significantly improve the latter's solidification performance with respect to ameliorating Cr pollution. In this paper, the compressive strength, microstructure, pH in the process of sample hydration, and leaching toxicity of solidified forms were studied by adding various amounts of Cr3+ into MPC. The setting time of MPC decreased at first and then increased as the Cr3+ concentration increased. The added Cr3+ reacted with the phosphate ions to form mineral phases, which changed the MPC matrix structure. The matrix's compressive strength was higher when the M/P ratio (MgO/KH2PO4 mass ratio) was smaller. When the concentration of Cr3+ was constant, and the M/P ratio was low (< 4:1), the matrix's compressive strength increased as the M/P ratio increased. The presence of Cr3+ changed the system's pH and affected the hydration products' morphology; this trend strengthened as the Cr3+ concentration increased. The highest leaching concentration of Cr3+ was 0.255 mg/L, and the concentration decreased as the M/P ratio decreased. During solidification, the appropriate proportion of MPC can be selected according to the concentration of Cr3+ to achieve better solidification performance.

Tissue expression profile, polymorphism of IGF1 gene and its effect on body size traits of Dezhou donkey.

Insulin-like growth factor 1 (IGF1) is a multifunctional cell proliferation regulator that plays a critical role in regulating animal growth and development. In this study, the expression level of IGF1 gene in different tissues of Dezhou donkey in different periods was investigated by RT-qPCR. Meanwhile, two mutation sites were identified within the IGF1 gene and its effect on body size traits of Dezhou donkey was analysed. The results showed that the expression level of the adult donkey IGF1 gene in heart, liver, spleen, lung, renal and gastric tissues is higher than that of the young donkeys, but the young donkeys are significantly higher in muscle tissues than the adult donkeys. The IGF1-1 and IGF1-2 loci showed a trend that the GG mutant was larger than other genotypes in the growth traits of both male and female donkeys, among which the IGF1-1 loci had a significant association with the chest circumference and chest depth of male donkeys (P < 0.05), and the IGF1-2 loci had a significant association with the chest circumference of female donkeys. Haplotype combination Hap1Hap1 (GG-GG) showed a greater tendency than Hap2Hap2 (AA-GG) combination in terms of growth traits, reflecting that the results were consistent with the analysis results of genotypes, which also proved the analysis results of genotypes and growth traits had certain reliability. In summary, the IGF1 gene is a candidate gene for growth and development, and its polymorphisms can be used as the molecular markers for Dezhou donkey breeding.

Mechanical and Durability Performance Improvement of Natural Hydraulic Lime-Based Mortars by Lithium Silicate Solution.

Natural hydraulic lime (NHL) as a building material has been widely used to restore the historic structure. However, the slow growth rate of strength and durability limits its engineering application. In this work, the NHL-based mortars were pretreated by lithium silicate (LS) solution impregnation and surface spraying. The results show that the compressive strength, surface hardness, and freeze-thaw cycle (FTC) resistance of NHL-based mortar were greatly improved after LS pretreatment. Specifically, the compressive strengths of the sample increased by about 32.7-52.0%. LS was sprayed on the sample's surface (about 0.2 kg/m2) and the surface hardness increased by up to 10 grades. Compared with the control samples, the weight loss of treated samples decreased by about 31.6-43.8%. A rehydration process to generate the hydrated calcium silicate gel (C-S-H) was observed between calcium hydroxide (CH) and LS, which can decrease the sample's porosity and form a silicate coating on the surface. With an increase in the concentration of LS, the macropores (50-10,000 nm) content decreased, while the mesopores (10-50 nm) and nanopores (less than 10 nm) increased. This work reveals that the LS pretreatment provides a potential route to improve NHL-based mortar's mechanical properties and durability.

Utilization of oil-based mud drilling cuttings wastes from shale gas extraction for cement clinker production.

A large amount of oil-based mud drilling cuttings (OBMDC) are generated during shale gas extraction, which adversely affects the environment. In order to realize the resource utilization of waste, the object of this paper is to study the feasibility of OBMDC to produce cement clinker. The results showed that at relatively low calcination temperature, adding a certain amount of OBMDC can produce cement clinker successfully and reduce fuel consumption. The compressive strength, hydration performance, and physical characteristics of clinker with 0, 3, 6, and 9% OBMDC were investigated by chemical analysis methods, X-ray diffraction, isothermal calorimetry, mercury intrusion, and energy dispersive spectroscopy. The results showed that the formulated cement has good hydration performance and the compressive strength also meets relevant standards. The heavy metal ions leaching test showed that the preparation of cement clinker by a low amount of OBMDC could effectively reduce the toxicity of OBMDC. In general, the preparation of cement clinker by OBMDC can realize the resource utilization of waste, effectively reduce its toxicity, and play a positive role in environmental protection.

Expression profiles and polymorphic identification of the ACSL1 gene and their association with body size traits in Dezhou donkeys.

Finding out the genetic mechanism of growth and development traits and the development of related molecular markers can help improve the breeding of livestock. The long-chain acyl coenzyme A synthase 1 (ACSL1) gene plays a major role in lipid synthesis and fatty acid catabolism. However, there are few studies on the ACSL1 gene polymorphism of Dezhou donkeys. This study analyzed the expression level of the ACSL1 gene in different tissues of young and adult Dezhou donkeys, as well as association analysis of four gene polymorphic loci in 450 individuals. The results showed that expression levels of the ACSL1 gene are higher in heart, liver, spleen, lung, renal, gastric and muscle tissues of adult donkeys than in those of young donkeys. In the association analysis between genotype and body size traits, the wild genotype DD at the ACSL1-1 locus in female and male donkeys was greater than the mutant genotype II ( P < 0.05 ); genotype II of ACSL1-2 was significantly higher than that of DD in withers height, body length, rump width and body weight of male donkeys ( P < 0.05 ); and ACSL1-3 showed a tendency for the wild genotype II to be greater than the mutant genotype DD in female and male donkeys ( P < 0.05 ). In addition, among the five haplotype combinations constructed, Hap3Hap3 (II-II-DD-DD) and Hap6Hap6 (DD-II-II-II) haplotype combinations were superior to other haplotype combinations in growth traits, which also indicated that the results of haplotype combination association analysis and genotype association analysis tended to be the same. In conclusion, the results of this study indicate that the polymorphic loci of the ACSL1 gene can be used as candidate molecular markers for the growth and development of Dezhou donkeys, and provide a theoretical reference for the breeding of Dezhou donkeys.

Detection of Selection Signatures Underlying Production and Adaptive Traits Based on Whole-Genome Sequencing of Six Donkey Populations.

Donkeys (Equus asinus) are an important farm animal. After long-term natural and artificial selection, donkeys now exhibit a variety of body sizes and production performance values. In this study, six donkey breeds, representing different regions and phenotypes, were used for second-generation resequencing. The sequencing results revealed more than seven million single nucleotide variants (SNVs), with an average of more than four million SNVs per species. We combined two methods, Z-transformed heterozygosity (ZHp) and unbiased estimates of pairwise fixation index (di) values, to analyze the signatures of selection. We mapped 11 selected regions and identified genes associated with coat color, body size, motion capacity, and high-altitude adaptation. These candidate genes included staining (ASIP and KITLG), body type (ACSL4, BCOR, CDKL5, LCOR, NCAPG, and TBX3), exercise (GABPA), and adaptation to low-oxygen environments (GLDC and HBB). We also analyzed the SNVs of the breed-specific genes for their potential functions and found that there are three varieties in the conserved regions with breed-specific mutation sites. Our results provide data to support the establishment of the donkey SNV chip and reference information for the utilization of the genetic resources of Chinese domestic donkeys.

Genotypes and haplotype combination of ACSL3 gene sequence variants is associated with growth traits in Dezhou donkey.

Exploring molecular markers related to economic traits of livestock is of great significance to breeding. Long-chain fatty acid COA synthetase (ACSL) plays a crucial role in lipid synthesis and metabolism, which may affect animal growth. This study was to investigate the polymorphism of ACSL gene and its association with the growth trait of the donkey. Three insertions and two deletions were detected on the introns of ACSL3 gene in 450 Dezhou donkeys using polyacrylamide gel electrophoresis. After that, linkage disequilibrium analysis found that there was a strong linkage among ACSL3 gene loci in Dezhou donkey. Association analysis of growth traits showed that ACSL3-1, ACSL3-2, ACSL3-3, and ACSL3-4 loci were significantly associated with body weight and other growth traits (P < 0.05). Furthermore, five high frequency haplotypes were identified in Dezhou donkey, and haplotype combination analysis showed that among the first three high-frequency combinations, the low-frequency Hap3Hap3 (II-DD-II-DD-DD) homozygous haplotype combination was lower than the other two groups (Hap1Hap1, Hap5Hap5) in the chest width and chest depth (P < 0.05) of the female. Conclusively, the results of this study indicated that the polymorphisms in ACSL3 gene can be used as molecular markers to participate in donkey breeding.

Analysis of Long Non-Coding RNA and mRNA Expression Profiling in Immature and Mature Bovine (Bos taurus) Testes.

Testis development and spermatogenesis are strictly regulated by numbers of genes and non-coding genes. However, long non-coding RNAs (lncRNAs) as key regulators in multitudinous biological processes have not been systematically identified in bovine testes during sexual maturation. In this study, we comprehensively analyzed lncRNA and mRNA expression profiling of six bovine testes at 3 days after birth and 13 months by RNA sequencing. 23,735 lncRNAs and 22,118 mRNAs were identified, in which 540 lncRNAs (P-value < 0.05) and 3,525 mRNAs (P-adjust < 0.05) were significantly differentially expressed (DE) between two stages. Correspondingly, the results of RT-qPCR analysis showed well correlation with the transcriptome data. Moreover, GO and KEGG enrichment analyses showed that DE genes and target genes of DE lncRNAs were enriched in spermatogenesis. Furthermore, we constructed lncRNA-gene interaction networks; consequently, 15 DE lncRNAs and 12 cis-target genes were involved. The target genes (SPATA16, TCF21, ZPBP, PACRG, ATP8B3, COMP, ACE, and OSBP2) were found associated with bovine sexual maturation. In addition, the expression of lncRNAs and cis-target genes was detected in bovine Leydig cells, Sertoli cells, and spermatogonia. Our study identified and analyzed lncRNAs and mRNAs in testis tissues, suggesting that lncRNAs may regulate testis development and spermatogenesis. Our findings provided new insights for further investigation of biological function in bovine lncRNA.

A Novel 13 bp Deletion within the NR6A1 Gene Is Significantly Associated with Growth Traits in Donkeys.

Nuclear receptor subfamily 6, group A, member 1 (NR6A1), as an important member of the nuclear receptor family, plays an important role in regulating growth, metabolism, and differentiation of embryonic stem cells. For this reason, the NR6A1 gene is considered to be a promising candidate for economic traits and was found to be associated with body size traits in many livestock. However, no studies have been conducted on NR6A1 in donkeys so far. Thus, in this research, we focused on donkeys and identified a 13 bp deletion in intron-1 of the NR6A1 gene among 408 individuals from Guanzhong and Dezhou donkeys using polyacrylamide gel electrophoresis. Three genotypes were identified, namely II, ID, and DD. The association analysis indicated that the body lengths and body heights5f genotype II individuals were significantly different to those of genotype ID in Dezhou donkeys. Conclusively, the 13 bp deletion was associated with growth traits in both Guanzhong donkeys and Dezhou donkeys, indicating that the NR6A1 gene could be a possible candidate gene in marker-assisted selection for donkey breeding programs.

The Distribution Characteristics of a 19-bp Indel of the PLAG1 Gene in Chinese Cattle.

Pleomorphic adenoma gene 1 (PLAG1) belongs to the PLAG family of zinc finger transcription factors. In cattle, a 19-bp insertion/deletion (indel) was identified in intron 1 of the PLAG1 gene (GenBank Accession No. AC_000171.1). Researches showed that the indel is polymorphic in Chinese cattle breeds such as Qinchuan cattle, Pinan cattle, Xianan cattle, and Jiaxian red cattle, and correlation analysis showed that the polymorphism is related to the height of these cattle breeds. Chinese cattle breeds show a difference in height related to geographical distribution. We investigated the distribution of the 19-bp indel polymorphism in 37 cattle breeds, including 1354 individuals. The results showed that there were three genotypes and two alleles (W, 366 bp; D, 347 bp). From northern cattle to southern cattle, the frequency of W allele gradually decreased, while the frequency of D allele showed an opposite trend, which was consistent with the distribution of cattle breeds of different height in China. Therefore, the polymorphism of this indel may be related to the regional distribution of cattle breeds in China. In addition, we chose Yunling cattle with a mixed genetic background to study the genetic effects of the 19-bp indel on body size traits. Statistical analysis showed that PLAG1 was significantly associated with the body height, cross height, and chest circumference of Yunling cattle (p < 0.05). This study provides new evidence that the 19-bp indel of the PLAG1 gene is a highly effective trait marker that can be used as a candidate molecular marker for cattle breeding.

Two Novel SNPs in RET Gene Are Associated with Cattle Body Measurement Traits.

The rearrangement of the transfection (RET) gene, which mediates the functions of the ganglion in the gastrointestinal tract, plays an important role in the development of the gastrointestinal nervous system. Therefore, the RET gene is a potential factor influencing animal body measurement. The aim of this study was to reveal the significant genetic variations in the bovine RET gene and investigate the relationship between genotypes and body measurement in two Chinese cattle breeds (Qinchuan and Nanyang cattle). In this study, two SNPs (c.1407A>G and c.1425C>G) were detected in the exon 7 of RET gene by sequencing. For the SNP1 and SNP2, the GG genotype was significantly associated with body height, hip height, and chest circumference in Qinchuan cattle (p < 0.05). Individuals with an AG-CC genotype showed the lowest value of all body measurement in both breeds. Our results demonstrate that the polymorphisms in the bovine RET gene were significantly associated with body measurement, which could be used as DNA marker on the marker-assisted selection (MAS) and improve the performance of beef cattle.

Identification and characterization of circular RNAs in Qinchuan cattle testis.

Circular RNA (circRNA) is a new class of non-coding RNA that has recently attracted researchers' interest. Studies have demonstrated that circRNA can function as microRNA sponges or competing endogenous RNAs. Although circRNA has been explored in some species and tissues, the genetic basis of testis development and spermatogenesis in cattle remains unknown. We performed ribo-depleted total RNA-Seq to detect circRNA expression profiles of neonatal (one week old) and adult (4 years old) Qinchuan cattle testes. We obtained 91 112 596 and 80 485 868 clean reads and detected 21 753 circRNAs. A total of 4248 circRNAs were significantly differentially expressed between neonatal and adult cattle testes. Among these circRNAs, 2225 were upregulated, and 2023 were downregulated in adult cattle testis. Genomic feature, length distribution and other characteristics of the circRNAs in cattle testis were studied. Moreover, Gene Ontology and KEGG pathway analyses were performed for source genes of circRNAs. These source genes were mainly involved in tight junction, adherens junction, TGFß signalling pathway and reproduction, such as PIWIL1, DPY19L2, SLC26A8, IFT81, SMC1B, IQCG and TTLL5. CircRNA expression patterns were validated by RT-qPCR. Our discoveries provide a solid foundation for the identification and characterization of key circRNAs involved in testis development or spermatogenesis.