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Background: Gleditsia sinensis is a significant tree species from both ecological and economic perspectives. However, its growth is hampered by temporary droughts during the seedling stage, thereby impeding the development of the G. sinensis industry. Drought stress and rehydration of semi-annual potted seedlings using an artificial simulated water control method. RNA sequencing (RNA-seq) analyses were conducted on leaves collected from highly resistant (HR) and highly susceptible (HS) seedling families at five different stages during the process of drought stress and rehydration to investigate their gene expression patterns. Results: The differentially expressed genes (DEGs) were predominantly enriched in pathways related to "chloroplast" (GO:0009507), "photosynthesis" (GO:0015979), "plant hormone signal transduction" (map04075), "flavonoid biosynthesis" (map00941), "stress response", "response to reactive oxygen species (ROS)" (GO:0000302), "signal transduction" (GO:0007165) in G. sinensis HR and HS families exposed to mild and severe drought stress. Additionally, the pathways related to "plant hormone signal transduction" (map04075), and osmoregulation were also enriched. The difference in drought tolerance between the two families of G. sinensis may be associated with "transmembrane transporter activity" (GO:0022857), "stress response", "hormones and signal transduction" (GO:0007165), "cutin, suberine and wax biosynthesis" (map00073), "ribosome" (map03010), "photosynthesis" (map00195), "sugar metabolism", and others. An enrichment analysis of DEGs under severe drought stress suggests that the drought tolerance of both families may be related to "water-soluble vitamin metabolic process" (GO:0006767), "photosynthesis" (map00195), "plant hormone signal transduction" (map04075), "starch and sucrose metabolism" (map00500), and "galactose metabolism" (map00052). Osmoregulation-related genes such as delta-1-pyrroline-5-carboxylate synthase (P5CS), Amino acid permease (AAP), Amino acid permease 2 (AAP2) and Trehalose-phosphate synthase (TPS), as well as the antioxidant enzyme L-ascorbate peroxidase 6 (APX6), may be significant genes involved in drought tolerance in G. sinensis. Five genes were selected randomly to validate the RNA-seq results using quantitative real-time PCR (RT-qPCR) and they indicated that the transcriptome data were reliable. Conclusions: The study presents information on the molecular regulation of the drought tolerance mechanism in G. sinensis and provides a reference for further research on the molecular mechanisms involved in drought tolerance breeding of G. sinensis. [ABSTRACT FROM AUTHOR]

In order to study the influence of the space linkage system on the stability of the straddle-type monorail vehicle with single-axle bogies, the sensitivity analysis of the space linkage system is identified based on the Pearson coefficient method to determine the importance of each component of the single-axle bogies. The dynamics model of straddle-type monorail vehicle with single-axle bogies is established by the multi-rigid body dynamics. The Pearson analysis method is used to identify the key parameters of the space linkage system. Based on that, dynamic response optimization model of space bar system is developed to carry out a multi-objective suspension design optimization process. The results show that the maximum sensitivity parameter for the RMS value of yaw acceleration and pitch angle acceleration is the length of the longitudinal tow bar; there is a correlation of approximately 0.088 between the stiffness K and the damping coefficient C of the hydraulic shock absorber. After optimization the root mean square of lateral acceleration of the optimized single-axle bogie vehicle is reduced by 6.0%. [ABSTRACT FROM AUTHOR]

A test method for controlling the stress release rate of the tunnel by adjusting the confining pressure is proposed based on the engineering background of Dongmachang No. 1 Tunnel of Huali Expressway to explore a suitable excavation method of soft rock tunnel. Based on the relationship between stress release rate, displacement release rate, and longitudinal advance of excavation face, the model test of tunnel excavation is carried out. On this basis, combined with the horizontal loading test and field monitoring results, the influence of three excavation methods, the three-bench method, three-bench with reserved core soil method, and three-bench seven-step method, on the mechanical behavior of the tunnel is studied. The research shows that the load shared by the double-layer initial support is not equal, and the second-layer initial support only bears 20% of the pressure of the first-layer initial support; replacing the three-bench method with the three-bench core soil method and the three-bench seven-step method can reduce the deformation of the surrounding rock by 8.7~12.4%, and the load borne by the supporting structure is transferred from the second layer to the first layer. In order to take into account the safety and efficiency of tunnel construction, it is recommended to use the three-bench core soil method for excavation. The research results can provide a theoretical reference for the construction of related tunnel projects. [ABSTRACT FROM AUTHOR]

G. sinensis is a crucial tree species in China, possessing important economic and ecological value, and having a wide geographical distribution. G. sinensis seedlings is highly vulnerable to the drought-rehydration-drought cycle during their growth, and there is a lack of quantitative and systematic research on the physiological mechanisms of drought resistance and rehydration in G. sinensis. There is also a lack of good drought-resistant families and reliable methods for evaluating drought resistance, which severely hinders the selection and promotion of drought-resistant G. sinensis families and the industry's development. Therefore, this study selection 58 families seedlings of G. sinensis to drought stress and rehydration using an artificial simulated water control method in potted seedlings. The aim was to compare the effects of different levels of drought and rehydration on the growth and physiological indices of seedlings from different families. Identification of drought-resistant families and dependable drought related indices and techniques, the explanation of divergence in drought stress effects on various drought-resistant seedlings and the mechanisms underpinning growth and physiological responses, and the provision of theoretical reference for G. sinensis drought-resistant variety selection and cultivation. The Drought Resistance Index (DRI) served as the primary indicator, supplemented by growth, leaf morphology, and photosynthetic physiological indicators, to thoroughly assess and identify five distinct drought tolerant taxa while also selecting five representative families. Soluble protein (SP), proline (Pro), and malondialdehyde (MDA) contents, as well as the activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) in seedlings from the five families, increased as the degree of drought intensified. The highest values were appeared during periods of severe drought, and gradually decreased after subsequent rehydration. Principal component analysis (PCA) revealed MDA and soluble sugars (SS) as the primary predictors of drought and rehydration response in G. sinensis seedlings respectively. Changes in osmoregulatory substance content and increased antioxidant enzyme activity may be crucial for responding to drought tolerance mechanisms. Leaf morphological indicators, seedling height, soil plant analysis development (SPAD) value, photosynthetic indicators, and MDA are dependable parameters for assessing the drought tolerance of G. sinensis seedlings. When assessing the drought-resistance of seedlings using physiological indicators such as photosynthesis, a comprehensive analysis should incorporate multiple indicators and methods. This evaluation approach could serve as a reference for screening exceptional drought-resistant families of G. sinensis. [ABSTRACT FROM AUTHOR]

A microfiber reflective ethanol gas sensing probe was designed and fabricated. The single-mode fiber was heated and stretched to prepare a microfiber taper, on which a mixed material of ZnO nanosheets and UV glue was built by the dip-coating method. The influencing factors on its sensing performance for ethanol have been discussed, including the dozen ratio of ZnO nanosheets, UV glue materials, and end-face morphology. As the concentration of ethanol gas increased, the intensity of the reflection spectrum increased with the responding sensitivity of 7.28 × 10−4 dBm/ppm. The exchanging efficiency of the optical signal is enhanced by the strong evanescent field of the microfiber taper. This sensing probe is convenient for high-density integration and working in a small space and is capable of high-performance monitoring for ethanol at room temperature. [ABSTRACT FROM AUTHOR]

The hot corrosion behavior of Al-Co-Y co-deposited coatings on TiAl alloy was investigated in 25% NaCl + 75% K2SO4 molten salt at 850 °C. Results show that O, S and other corrosive media are preferentially corroded by the α2 phase of the TiAl matrix, generating corrosion products with poor density and adhesion, resulting in rapid corrosion. The Al-Co-Y co-deposited coating specimens form a dense Al2O3 film during the hot corrosion incubation, which effectively improves the anti-hot corrosion performance of TiAl alloy. During hot corrosion, the Al2O3 film is dissolved and ruptured under the action of mixed salts, losing its protective properties. [ABSTRACT FROM AUTHOR]

The microfiber cascaded double‐tapers were constructed and used as a Mach–Zehnder interferometer by a two‐step fiber stretching process using a normal fiber splicer and a multifunctional fiber stretching machine. The morphological parameters, such as waist diameter and taper length were optimized by the simulation models. The refractive index sensing performance has been theoretically and experimentally demonstrated and compared. A sensitivity of 2606.39 nm/RIU of one Mach–Zehnder interferometer with microfiber double‐apers (central distance is ~1 cm) was obtained when the RI values changed from 1.3309, 1.3319, 1.3327, 1.3336, 1.3344–1.3352. This study proposed a novel way to design interesting microfiber devices, which will be a promising candidate for exploring optical fiber biosensors with compact structures. [ABSTRACT FROM AUTHOR]

The disposal of soil containing humic acid (HA) poses an increasingly difficult problem for geotechnical environmental engineering. In this study, the unconfined compressive strength (UCS) test of cement-soil with different HA contents is conducted to analyze the effect of HA on the strength of cement-soil. Mercury intrusion porosimetry (MIP), scanning electron microscopy (SEM), and X-ray diffraction (XRD) experiments reveal the effective mechanism of HA on the strength of cement-soil from the microscopic level. The results show that the strength of cement-soil decreases gradually with the increase of HA content. The failure mode of cement-soil slightly changed from brittle failure to plastic failure. The microscopic test shows that the incorporation of HA will lead to the apparent enlargement of the pores in the cement-soil. The large pores in the sample increase, the small micropores decrease, and the structure tends to be loose and overhead. The increased HA content added will significantly reduce the cement hydration products and destroy the cementation of the hydration products. [ABSTRACT FROM AUTHOR]

This letter describes a sensitive quartz-enhanced photoacoustic spectroscopy (QEPAS) sensor for measuring ammonia (NH3) concentrations based on a custom quartz tuning fork (QTF) with a small gap of 200 μm. The signal was enhanced by adding a microresonator (mR) with an optimum length of 5 mm to the bare QTF. Wavelength modulation spectroscopy with second-harmonic detection was adopted to reduce the noise level and simplify the data processing. After optimization of the laser modulation depth, a minimum detection limit of 22.6 ppm was obtained. [ABSTRACT FROM AUTHOR]

We demonstrate a diode-pumped acousto-optically (A-O) Q-switched 1,066 nm laser with a novel Nd:Gd0.69Y0.3TaO4 mixed crystal. At a modulation repetition rate of 10 kHz and an absorbed pump power of 15 W, the pulsed laser output characteristics are: average output power 2.41 W, pulse width 27.2 ns, pulse energy 241 μJ, and pulse peak power 8.86 kW. At a modulation repetition rate of 20 kHz and an absorbed pump power of 15 W, the characteristics are: average output power 2.68 W, pulse width 30.1 ns, pulse energy 134 μJ, and pulse peak power 4.45 kW. [ABSTRACT FROM AUTHOR]

Background and Aims Primary ciliary dyskinesia ( PCD) is a rare, genetically heterogeneous disorder. Genetic defects affecting motility of cilia and flagella cause chronic destructive airway disease, situs inversus and, frequently, male infertility in PCD. To date, although several genes have been implicated in PCD, the genetic bases of most cases of PCD remain elusive. Methods By applying a whole-exome sequencing strategy, we reported a case of PCD carrying a novel mutant alleles in CCDC40 gene, and did literature review. Results A 36-year-old nonsmoking Chinese man suffered from chronic cough since childhood and an 8-year history of primary infertility. Lung biopsy showed respiratory bronchiolitis. Chest images showed bronchiectasis and situs inversus. Semen analysis showed high sperm counts and poor sperm motility. Transmission electron microscopy ( TEM) of cilia cross-sections showed ultrastructural defects, including inner dynein arms ( IDA) defect and axonemal disorganization. To identify gene mutations that cause PCD, we performed exome sequencing to analyze genome of this patient, and discovered a previously uncharacterized mutant alleles ( NM_001243342.1:c.2609G>A; p. R870H) in CCDC40 gene. In addition, we summarize the PCD disease-causing genes and CCDC40 mutant sites based on current literature. Conclusions We identified a novel mutant alleles in CCDC40 gene, which altered the protein sequence and resulted in the ultrastructural defects in the microtubule structure of cilia. Thereby, these defects lead to the patient with bronchiectasis, bronchiolitis and infertility. [ABSTRACT FROM AUTHOR]

Objective: The objective of this study was to measure the 3′-untranslated region (3′-UTR) polymorphism lengths in peripheral blood mononuclear cells (PBMCs) from uremia patients. Method: We sequenced the alternative polyadenylation sites in the 3′-UTR of PBMCs from 10 uremic patients and 10 healthy people to detect different gene expression levels between uremia patients and healthy controls. Quantitative reverse transcription polymerase chain reaction was used as validation.Result: Compared with the healthy control group, 691 genes in uremic patients had significantly different 3′-UTR lengths. Of these genes, 475 genes showed shortened 3′-UTRs, and the 3′-UTRs of 216 genes were lengthened. The verification results matched the original sequencing results.Conclusion: There were significant differences in 3′-UTR lengths between uremic patients and healthy controls, and analysis of the differential genes may contribute to the understanding of uremia pathogenesis. [ABSTRACT FROM AUTHOR]

Recent studies have shown that circular ribonucleic acids have differential expression in some diseases. This study compared the expression levels of five circular ribonucleic acids between patients of primary hepatic carcinoma following liver transplantation and healthy individuals for searching a new diagnostic biomarker about primary hepatic carcinoma. We chose differentially expressed targeted circular ribonucleic acids according to fold change ≥2.0 or ≤–2.0 between circular ribonucleic acids microarray of perioperative liver transplantation and normal controls. Then we used the Arraystar home-made micro-ribonucleic acid target prediction software based on TargetScan and miRanda to predict circular ribonucleic acid/micro-ribonucleic acid interactions. And we assess the expression levels of hsa_circ_100571, hsa_circ_400031, hsa_circ_102032, hsa_circ_103096, and hsa_circ_102347 in the peripheral blood of normal controls and liver transplantation patients before transplantation and on the first, third, and seventh days after transplantation by real-time quantitative polymerase chain reaction. We chose five circular ribonucleic acids, two of which have been correlated with micro-ribonucleic acid–related carcinoma recurrence after liver transplantation, hepatocellular carcinoma and analyzed their expression with 2–△△Ct method. The expression level of hsa_circ_100571 and hsa_circ_400031 on day 1 after liver transplantation was higher than pre-transplantation (p < 0.01), and these levels showed a declining trend on post-transplantation. The expression level of hsa_circ_102032 and hsa_circ_103096 on day 1 after liver transplantation was lower than pre-transplantation (p < 0.01) and decreased on post-transplantation. There were the significantly different expressions between the post-transplantation day 7 and normal control (p < 0.01). The expression level of hsa_circ_102347 on day 1 after liver transplantation was lower than pre-transplantation (p < 0.01). This expression showed a declining trend on post-transplantation, and the postoperative day 7 level was similar to normal control (p > 0.05). Five types of circular ribonucleic acid–related micro-ribonucleic acids had varying degrees of upregulation and downregulation between perioperative transplantation of primary hepatic carcinoma patients and normal controls; the hsa_circ_102347 is most likely to have association with primary hepatic carcinoma. [ABSTRACT FROM AUTHOR]