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Natural gas transmission pipelines installed in seismic and permafrost regions are vulnerable to cyclic loads with a large strain amplitude. Under these conditions, the pipe may fail in extremely low cycles, a situation which is also known as extremely low cycle fatigue (ELCF) failure. The fracture mechanism of ELCF shows significant difference to that of low cycle fatigue, and the ELCF life usually deviates from the Coffin–Manson law. Thus, it is essential to develop an effective model to predict ELCF failure of the pipeline. In this study, a series of ELCF tests is performed on pipeline steel (X70). A damage coupled mixed hardening model is developed to simulate the fracture behaviors. Continuum damage law under monotonic load is extended to cyclic load by introducing the effective equivalent plastic strain. By assuming the cyclic softening is induced by the damage accumulation, the damage parameters are fitted directly from the peak stress in each cycle. Then, the model is input into commercial software ABAQUS with a user material subroutine to simulate the fracture behaviors of these specimens. The simulation results show good agreements with the test results both under cyclic and monotonic load, which verifies the reliability of the model.

Objective: To explore the applicability of bone reamer and trephine for foraminoscopy in percutaneous endoscopic lumbar discectomy(PELD), and to provide a theoretical basis for foraminoplasty options in clinical practice. Methods:This study was a prospective cohort study. Sixty-three consecutive patients who underwentPELD for lumbar disc herniation between May 2021 and July 2022 were analysed. Foraminoplasty were performed by bone reamer or trephine. The amount of bone resected and the area enlarged during foraminoplasty by both tools were measured by 3D slicer as well as Digimizer software, and the numbers of fluoroscopic views were recorded. Results: The bone reamer resected less bone in the Superior Articular Process (SAP) than the trephine (t=17.507, PConclusion:Bone reamer was safer and trephine was more efficient for foraminoscopy in PELD. An area of preoperative foraminoplasty zone of 54.55 mm²can be used as a critical value: bone reamer reduced the risk for cases above the value, while trephine improved the efficiency for cases less than the value.

Icotinib is a first-generation inhibitor of epidermal growth factor receptor, which has been approved by the Chinese National Medical Products Administration, for the treatment of non-small cell lung cancer with epidermal growth factor receptor sensitive mutations. In addition, icotinib also shows moderate activity in other solid tumors driven by epidermal growth factor receptor, including non-small cell lung cancer with epidermal growth factor receptor rare non-resistant mutations, and esophageal cancer with epidermal growth factor receptor amplification or overexpression. This article reviews the efficacy of icotinib in different solid tumors with different epidermal growth factor receptor alterations.

Objective. This research is aimed at studying the effect of microwave ablation combined with the antiprogrammed death- (PD-) 1 monoclonal antibody on T cell subsets and long-term prognosis in patients suffering from non-small-cell lung cancer (NSCLC). Methods. Employing the random number table technique, a total of 122 NSCLC patients who received treatment at our hospital between May 2015 and June 2019 were selected and assigned to the observation group and the control group, and each group comprised 61 patients ( n = 61 ). While the control group received only anti-PD-1 monoclonal antibody treatment, the observation group received microwave ablation in combination with anti-PD-1 monoclonal antibody. The clinical efficacy was observed for both groups. The levels of T cell subsets (CD3+, CD4+, and CD8+), serum tumor markers (squamous cell carcinoma antigen (SCCA), cytokeratin Ig fragment (CYFRA21-1), and serum carcinoembryonic antigen (CEA)), nuclear factor kappa B (NF-κB), protease C (PKC), and mitogen-activated protein kinase (MAPK) mRNA expression between the two groups were compared. The frequency of adverse reactions was observed in both groups. The survival time of both the groups was recorded over the course of three years of follow-up. The Kaplan-Meier method was employed for analyzing the survival of both the control and the observation group. Results. The response rate (RR) of the observation group (80.33%) was considerably greater in comparison to that of the control group (62.30%) ( P < 0.05 ). Following treatment, the observation group’s levels of CD3+, CD4+, CD8+, SCCA, CyFRA21-1, and CEA and the mRNA expressions of NF-κB, PKC, and MAPK were superior to those of the control group, with statistical significances (all P < 0.05 ). Between the two groups, there was no significant difference in the occurrence of adverse reactions ( P > 0.05 ). The observation group had greater 1-, 2-, and 3-year survival rates (57.38%, 39.34%, and 29.51%) than the control group (32.79%, 18.03%, and 8.20%), with statistically significant differences (all P < 0.05 ). Conclusion. Microwave ablation in combination with an anti-PD-1 monoclonal antibody could effectively improve the level of T cell subsets and serum tumor markers in NSCLC patients, resulting in a long-term prognosis of patients with good therapeutic effect and safety.

To evaluate the impact of quetiapine treatment on central set point of thyroid homeostasis in patients with acute phase schizophrenia.During Jan. 2016 to Dec. 2018, we conducted a retrospective cohort study in "the Second Affiliated Hospital of Xinxiang Medical University". All patients admitted for treatment of schizophrenia being euthyroid at admission and reevaluated for thyroid function during hospitalization were recruited and followed until discharge. Patients treated with mood stabilizers during hospitalization were excluded. Quetiapine use was the exposure measure. The primary outcomes were the parameters of central set point of thyroid homeostasis measured by "thyroid-stimulating hormone (TSH) index" and "thyroid feedback quantile-based index (TFQI)". Multiple regression models were used to estimate the association between quetiapine exposure and outcomes.A total of 1302 patients were enrolled in this study. Quetiapine exposure was associated with a more significant decline in the TSH index and TFQI, and the adjusted β and 95% confidence interval (CI) were -0.12 (-0.22, -0.01) and -0.10 (-0.15, -0.05), respectively. A dose-response association between quetiapine exposure and decline in TSH index and TFQI was observed (P 0.05). Sensitivity analyses restricting to patients under mono-atypical antipsychotic therapy, or selecting patients in the non-quetiapine group matched to quetiapine group yielded similar results.Quetiapine was associated with TSH index and TFQI reduction in a dose-response pattern, suggesting that impaired central set point may be involved in the mechanism by which quetiapine affects hypothalamus-pituitary-thyroid axis in acute phase schizophrenia patients.

Objective To explore the effect of astragaloside IV in promoting bone development by promoting the proliferation of precartilaginous stem cells. Methods To co-cultured the cells from the resting chondrocyte of growth plate and LaCroix of 24-hours old rats,and identified by FGFR-3 staining. Choosing astragaloside IV induce precartilaginous stem cells cultured in vitro, using Collagen type Ⅱ monoclonal antibody staining and MTT to test cell biological characteristics. Four 4 weeks old SD rats were selected and divided into an experimental group and control group, 24 rats in each group. The rats in the experimental group were injected with astragalus injection in a dose of 8.0g / kg once a day. The rats in the other group were injected with the same amount of normal saline. The 3rd and 5th week after feeding, 12 rats were killed, and the tibial length was measured by vernier caliper.Rusults The FGFR-3 staining was positive, which proved that the cultured cells were precartilaginous stem cells. Collagen typeⅡmonoclonal antibody staining is positive and the OD value detected by MTT test was higher, after astragaloside IV induced the precartilaginous stem cells. After astragaloside IV injection, the tibial length of experimental group measured by vernier caliper was significantly higher than that of the control group.Conclusion astragaloside IV can promote the proliferation and biological characteristics of precartilaginous stem cells, and then promote bone development.

Herein, a multifunctional aptamer probe mediated cascade amplification strategy has been constructed for sensitive and label-free detection of adenosine. First, the multifunctional aptamer probe was designed with an aptamer for adenosine identification and a template for cascade amplification. These two regions could partially hybridize with each other and formed a stem-loop structure. Thus, in the absence of adenosine, the probe could be inhibited by itself and the interference signals could be reduced effectively. In the presence of adenosine, the probe identified the adenosine, resulting in the conformational transformation and the release of the template. Then, the 3′-end of the probe-adenosine complex acted as primer to trigger the cascade amplification of strand displacement amplification (SDA) and catalytic hairpin assembly (CHA), yielding a lot of G-quadruplex. Finally, by inserting N-methy mesoporphyrin IX (NMM), an enhanced and label-free fluorescence signal was achieved. This strategy suggested a high sensitivity with a detection limit of 1.3 × 10−7 mol/L that attributes to the low interference signals of the probe and the amplification capability of the cascade amplification. Moreover, adenosine analysis in human urines was performed, indicating that this method was reliable and could be further used in the early clinical diagnosis and medical research.

Natural birnessite-like minerals are commonly enriched in various transitional metals (TMs), which greatly modify the mineral structure and properties. However few studies are yet conducted systematically on the effects of TM doping on birnessite reactivity towards Cr(III) oxidation. In the present study, the transformation behaviors of Cr(III) on Co-, Ni-, V-containing birnessites were investigated. Co and Ni doping generally decrease the mineral crystalline sizes and hydrodynamic sizes (DH) while V-doping greatly decreases the crystalline sizes but not the DH, owing to particle aggregation. Co and Ni firstly decrease and then increase the mineral zeta potentials (ζ) at pH4 while V decreases ζ. Electrochemical specific capacitances for Co-containing birnessites are gradually reduced, while those for Ni-doped birnessites are slightly reduced and for V-doped birnessites increased, which have a positively linear relationship with the amounts of Cr(III) oxidized by these samples. Cr(III) removal efficiencies from solution by these Co-, Ni- and V-containing birnessites are 26–51%, ∼62–72% and ∼96–100%, respectively, compared to ∼92% by pure birnessite. Cr(III) oxidation kinetics analysis demonstrates the gradual decrease of Mn(IV) and concurrent increase of Mn(III) and the adsorption of mainly Cr(III) on mineral surfaces. A negatively linear relationship exists between birnessite lateral sizes and the proportions of Mn(IV/III) consumed to oxidize Cr(III). Apparent initial Cr(III) oxidation rate (kobs) for Co-containing birnessites are greatly reduced, while those for Ni-doped samples moderately decreased and for V-doped samples first increased and then decreased. A positively or negatively linear relationship exists between kobs or the amount of Mn(II) released and the mineral Mn(IV) content respectively. Cr(III) oxidation probably initiates from layer edge sites of Ni-doped birnessites but the vacancies of Co- and V-containing birnessites. These results provide insights into the reaction mechanisms of Cr(III) with natural birnessite-like minerals.

In this work, we constructed a label-free and dual-amplified fluorescence aptasensor for sensitive analysis of adenosine based on exonuclease III (Exo III)-assisted DNA cycling and hybridization chain reaction (HCR). Firstly, we fabricated a trifunctional probe that consisting of the catalytic strand, the aptamer sequence and a streptavidin-magnetic nanobead (streptavidin-MNB). The streptavidin-MNB played a role of enrichment and separation to achieve a low background. The aptamer sequence was employed as a recognition element to bind the target adenosine, leading to the releasing of the catalytic stand. Then, the catalytic strand induced the Exo III-assisted DNA cycling reaction and produced a large amount of DNA fragments, which got a primary amplification. Subsequently, the DNA fragments acted as trigger strands to initiate HCR, forming nicked double helices with multiple G-quadruplex structures, which achieved a secondary amplification. Finally, the G-quadruplex structures bonded with the N-nethyl mesopor-phyrin IX (NMM) and yielded an enhanced fluorescence signal, realizing the label-free detection. In the proposed strategy, a small amount of adenosine can be converted to a large amount of DNA triggers, leading to a significant amplification for the target. This method exhibited a high sensitivity toward adenosine with a detection limit of 4.2×10 −7 mol L −1 , which was about 10 times lower than that of the reported label-free strategies. Moreover, this assay can significantly distinguish the content of adenosine in urine samples of cancer patients and normal human, indicating that our method will offer a new strategy for reliable quantification of adenosine in medical research and early clinical diagnosis.

As epoxy functional group has high anticancer activity, α,β-epoxyketones were designed and synthesized as new anticancer agents, and their structures were confirmed by UV, 1H NMR, IR, MS technigeces and elemental analysis. Their in vitro anticancer activities were evaluated by MTT method and the results showed that the compound 4c exhibited good activity with IC50 of 17.8, 22.0 and 24.1 µg/mL against A-549, Hela and HepG2 cells, respectively. The dose of LD50 of the mice by intragastric administration was 1864.4 mg/kg. Therefore, the α,β-epoxyketones could potentially provide as new anticancer agents.

Here, we developed an enzyme-free, label-free, and sensitive fluorescence cooperative amplification strategy based on a hairpin assembly circuit which coupled catalytic hairpin assembly (CHA) with hybridization chain reaction (HCR) for small molecule adenosine. A double-strand DNA probe with aptamer-catalysis strand (Apt-C) and inhibit strand (Inh) was designed for adenosine recognition and signal transduction which was named as Apt-C/Inh. Hairpins H1 and H2 were employed for constructing the CHA, and hairpins H3 and H4 for the HCR. Through the binding of adenosine and the Apt-C, the Inh was released from the Apt-C/Inh. Then the free Apt-C initiated the CHA through successively opening H1 and H2, generating H1/H2 complex and recyclable Apt-C. Next, the released Apt-C entered another CHA cycle, and the H1/H2 complex further initiated the HCR of H3 and H4 which induced the formation of the concatemers of H3/H4 complex. Such a process brought the two ends of hairpins H3 into close proximity, yielding numerous integrated G-quadruplexes which were initially sequestered in the stem and two terminals of H3. Finally, N-methyl mesoporphyrin IX (NMM) was added to generate an enhanced fluorescence signal. In the proposed strategy, driven only by the energy from hybridization, one target could trigger multiple HCR events via CHA-based target-cycle, leading to a remarkable enzyme-free amplification for adenosine. The detection limit could achieve as low as 9.7 × 10(-7) mol L(-1). Furthermore, G-quadruplexes were applied to construct label-free hairpin assembly circuit, which made it more simple and cost-effective. The satisfactory recoveries were obtained when detecting adenosine in spiked human serum and urine samples, demonstrating the feasibility of this detection strategy in biological samples.

Darzens condensation under optimized conditions gives novel α,β-epoxyketones (III) and (V) which are evaluated for their anticancer activity in vitro.

This paper proposes an algorithm that solves planar homography by iterative linear optimization. we iteratively employ direct linear transformation (DLT) algorithm to robustly estimate the homography induced by a given set of point correspondences under perspective transformation. By simple on-the-fly homogeneous coordinate adjustment we progressively minimize the difference between the algebraic error and the geometric error. When the difference is sufficiently close to zero, the geometric error is equivalently minimized and the homography is reliably solved. Backward covariance propagation is employed to do error analysis. The experiments prove that the algorithm is able to find global minimum despite erroneous initialization. It gives very precise estimate at low computational cost and greatly outperforms existing techniques.