206 research outputs found

    GENERATION OF CRACKS IN HIGHWAY EMBANKMENT ON BLACK COTTON SOIL

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    This research revealed the crack generation of the highway embankment from the water losing shrinkage of the wet black cotton soil (BCS), which is a type of soil with high swell-shrink potential. The road seepage meter was used to test the permeability of filling materials, which was used to replace BCS. The moisture content and embankment deflection of BCS foundation were measured after the rainy season. Based on the coupled consolidation theory for unsaturated soil, the change in additional tension stress of the embankment induced by water loss shrinkage of BCS was simulated by Abaqus. The results indicated that the rainfall seeped into the foundation through highly permeable refill materials to result in BCS expansion and decrease the embankment strength. After the rainy season, the additional tensile stress caused by water loss shrinkage of BCS induces cracking of highway embankment, and the maximum cracking depth often appears at the shoulder of highway. The deep and wide cracks are easy to appear in the low embankment constructed on a thick BCS foundation under strong evaporation

    Tris(ethylenediamine)cobalt(II) bis(tetra­hydroxypentaborate) dihydrate

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    The novel pentaborate with a transition-metal complex as counter-cation and with water of crystallization, tris(ethylenediamine)cobalt(II) bis[4,4′,6,6′-tetrahydroxy-2,2′-spirobi(cyclotriboroxane)(1−)] dihydrate, [Co(C2H8N2)3][B5O6(OH)4]2·2H2O, forms a three-dimensional supra­molecular framework through O—H⋯O hydrogen bonding among the [B5O6(OH)4]− anions with large channels along the a axis in which the templating [Co(en)3]2+ cations (en = ethylenediamine) and water mol­ecules are located. The crystal packing is consolidated by additional O—H⋯O and N—H⋯O hydrogen bonds

    Study on tightly coupled LiDAR-Inertial SLAM for open pit coal mine environment

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    With the rapid development of artificial intelligence and unmanned and other related disciplines, the intelligence and unmanned of coal mining equipment has become a new trend. The application of intelligent equipment will greatly improve the productivity of coal mine operations as well as personnel safety. In this environment, the existing LIDAR-based Simultaneous localization and mapping (SLAM) solution is prone to positioning drift and large mapping errors. To address these problems, a tightly coupled SLAM algorithm based on LiDAR (Light Detection and Ranging) and IMU (Inertial Measurement Unit) is proposed, which uses both LiDAR and IMU sensors as data inputs.The front-end uses an iterative extended Kalman filter to fuse the pre-processed LiDAR feature points with the IMU data and uses backward propagation to correct the radar motion distortion, the back-end uses the LiDAR relative positional factor to use the LiDAR inter-frame alignment results as a constraint factor together with the loopback factor to complete the global factor map optimization. The robustness and accuracy of the algorithm are verified using open source dataset and open pit coal mine field dataset. The experimental results show that the accuracy of the proposed algorithm is consistent with the current LiDAR SLAM algorithm in the urban structured environment, while the proposed algorithm improves the localization accuracy by 46.00% and 23.15% with higher robustness than the FAST-LIO2 and LIO-SAM tightly coupled algorithms for the open pit coal mine field environment of more than 2000 meters long, respectively

    A New Signal Feature Extraction Method -Fractal dimensions of Time- Frequency Domain

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    Abstract In this paper, vibratio

    Changes in thyroid function levels in female patients with first-episode bipolar disorder

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    ObjectivesThe identification of molecular biomarkers for bipolar disorder is anticipated to greatly improve the diagnosis and treatment of this disease. The objective of this case–control study is to determine whether the blood thyroid hormone levels in bipolar disorder patients are associated with different types of first onset.MethodsFrom August 1, 2020 to July 31, 2021 a total of 120 female patients diagnosed with bipolar disorder and hospitalized at Qingdao Mental Health Center were recruited as the case group, including 60 patients with depression as their first onset (depression first-episode group, DF) and 60 with mania/hypomania as their first onset (mania/hypomania first-episode group, M/HF). A group of 60 healthy adult females matching general demographic data, such as race and age, were selected as the control group. Blood samples were taken from both groups to measure serum triiodothyronine (T3), thyroxine (T4), free triiodothyronine (FT3), free thyroxine (FT4), and thyroid stimulating hormone (TSH) concentrations.ResultsThe duration of current onset in the M/HF group was significantly less than that in the DF group (23.1 ± 20.2 vs. 125.2 ± 41.0 days). About 27% of patients in the M/HF group had thyroid abnormalities, in contrast to 60% in the DF group. The blood T3 and T4 levels in both the M/HF group and the DF group, as well as the TF3 levels in the DF group, were significantly lower as compared to control. The M/HF group had significantly higher T3 and FT3 levels than the DF group. The blood T3 levels were inversely correlated with the Young’s Mania Scale score and the Hamilton Depression Scale score in both the M/HF and DF groups.ConclusionThyroid dysfunction resulting in reduced levels of blood thyroid levels may be involved in the disease progression of bipolar disorder, and correlated with the clinical symptoms in patients with depression or mania as the first episode

    Influence of parameters on the ultimate penetration depth of a double-plate vertically loaded anchor in soft clay

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    To make a new type of double-plate vertically loaded anchor (DPVLA) penetrate into clay deeper, the influence of parameters on the ultimate penetration depth of DPVLAs in soft clay should be investigated. The expression of the ultimate penetration depth applicable to DPVLAs in clay was determined in terms of the formula of the ultimate penetration depth of anchors with a wedge-shaped section. Based on the drag penetration tests, the movement direction of the bottom fluke of DPVLAs with different lengths of the bottom fluke and different included angles was obtained. By the finite-element method, the upper bound solutions of bearing capacity factors of DPVLAs with different included angles and different lengths of the bottom flukes were also obtained, which correspond to the maximum penetration depth induced by the initial orientation of the anchor. According to the determined expression of the ultimate penetration depth of DPVLAs, the ultimate penetration depth of DPVLAs with different included angles and different lengths of the bottom fluke in clay can be calculated. The results showed that increasing the length of the bottom fluke can increase the ultimate penetration depth when the included angles were the same for DPVLAs not only in the clay with zero strength at the seabed but also in the clay with uniform strength. However, when the length of the bottom fluke is the same, increasing the included angle of DPVLAs in clay can significantly reduce the ultimate penetration depth

    Association of dementia with immunoglobulin G N-glycans in a Chinese Han population

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    Immunoglobulin G (IgG) functionality can drastically change from anti- to proinflammatory by alterations in the IgG N-glycan patterns. Our previous studies have demonstrated that IgG N-glycans associated with the risk factors of dementia, such as aging, dyslipidemia, type 2 diabetes mellitus, hypertension, and ischemic stroke. Therefore, the aim is to investigate whether the effects of IgG N-glycan profiles on dementia exists in a Chinese Han population. A case–control study, including 81 patients with dementia, 81 age- and gender-matched controls with normal cognitive functioning (NC) and 108 non-matched controls with mild cognitive impairment (MCI) was performed. Plasma IgG N-glycans were separated by ultra-performance liquid chromatography. Fourteen glycan peaks reflecting decreased of sialylation and core fucosylation, and increased bisecting N-acetylglucosamine (GlcNAc) N-glycan structures were of statistically significant differences between dementia and NC groups after controlling for confounders (p \u3c 0.05; q \u3c 0.05). Similarly, the differences for these 14 initial glycans were statistically significant between AD and NC groups after adjusting for the effects of confounders (p \u3c 0.05; q \u3c 0.05). The area under the receiver operating curve (AUC) value of the model consisting of GP8, GP9, and GP14 was determined to distinguish dementia from NC group as 0.876 [95% confidence interval (CI): 0.815–0.923] and distinguish AD from NC group as 0.887 (95% CI: 0.819–0.936). Patients with dementia were of an elevated proinflammatory activity via the significant changes of IgG glycome. Therefore, IgG N-glycans might contribute to be potential novel biomarkers for the neurodegenerative process risk assessment of dementia

    Second-Line Combination Chemotherapy with Docetaxel and Nedaplatin for Cisplatin-Pretreated Refractory Metastatic/Recurrent Esophageal Squamous Cell Carcinoma

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    Background:There is an urgent need for an effective second-line chemotherapy regimen after failure of the standard cisplatin and 5-fluorouracil therapy.Patients and Methods:This study investigated the efficacy and toxicity of the combination of docetaxel (30 mg/m2) during a 1-hour infusion, followed by nedaplatin (50 mg/m2) during a 2-hour infusion (both drugs were administered on day 1 as an outpatient regimen and repeated every 2 weeks) as second-line chemotherapy for patients with cisplatin-pretreated refractory metastatic/recurrent esophageal squamous cell carcinoma after surgery.Results:Forty-six of the 48 patients (95.8%) were assessable for response. Partial response was confirmed in 13 of 48 cases yielding a response rate of 27.1% (95% confidence interval [CI], 14.5–39.7%). The median overall time to progression and overall survival was 3.1 months (95% CI, 2.3–3.9 months) and 5.9 months (95% CI, 3.9–7.8 months), respectively. The estimate of overall survival at 12 months was 16.7% (95% CI, 6.1–27.2%). Grade 3 anemia leucopenia, grade 4 anemia leucopenia and neutropenia were detected in only 4 (8.7%), 8 (17.4%), and 9 patients (19.6%), respectively.Conclusions:The combination chemotherapy of docetaxel and nedaplatin in the outpatient setting is well tolerated and useful as second-line chemotherapy for cisplatin-pretreated refractory metastatic/recurrent esophageal squamous cell carcinoma
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