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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]

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 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]

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 Mental retardation is characterized by lower intelligence compared to the average intelligence of persons the same age. These patients have low adaptive capacity acquired by society. The genetic factors of causing MR include monogenic disease, chromosome structural aberration, and chromosome number aberration and so on. We explored the cause of a Chinese family suffering from mental retardation. Methods We used karyotyping technology to determine the karyotype of the proband, and we used FISH to verify the result of the karyotyping. We used whole-exome sequencing to identify the disease-causing gene and used Sanger sequencing to verify the result of whole-exome sequencing to assess the family's gene expression. Results The G-banding of the karyotype revealed that the patient's karyotype is 46, XY. FISH revealed that the patient does not have a trisomy syndrome. The karyotype of the proband is normal. Using whole-exome sequencing, we identified 108,767 variants in the exome gene of the patient, including 101,787 SNPs and 6980 InDels. Combining clinical information and bioinformatics analysis, including databases filtering and SIFT analysis, we found ARHGAP4 in X chromosome was candidate MR disease-causing gene. PCR and Sanger sequencing results were consistent with whole-exome sequencing. ARHGAP4 (T491M) mutation was present in the genome of the proband and his mother is a carrier, while his father, sister, and brother do not carry this mutation. Conclusion According to clinical information, whole-exome sequencing results and Sanger verification results, ARHGAP4 (T491M) mutation may be disease-causing gene of the MR patient. The relation between ARHGAP4 mutation and MR clinical characteristic is needed to be illuminated with participation of more MR patients. [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]