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High-performance thermoplastic composites have been developed as significant structural materials for cutting-edge equipment in the aerospace and defence fields. However, the internal mechanism of processing parameters on mechanical properties in the manufacturing process of thermoplastic composite structures is still a serious challenge. The purpose of this study is to investigate the process/crystallization/property relationships for continuous carbon fiber (CF) reinforced polyether-ether-ketone (PEEK) composites. The composite laminates are fabricated according to orthogonal experiments via the thermoforming method. The mechanical performance is investigated in terms of crystallization properties and fracture morphology characterizations. Experimental results show that the mechanical performance and crystallization properties of thermoplastic composites are significantly affected by the coupling of processing parameters. The increased molding temperature, pressure, and holding time improve the degree of fiber/matrix infiltration and affect the crystallinity and crystalline morphology of the matrix, which further influences the mechanical properties of the composites. This is reflected in the test results that crystallinity has an approximately linear effect on mode-I interlaminar fracture toughness and transverse flexural modulus. As well as the higher molding temperature can destroy the pre-existent crystals to improve the toughness of the matrix, and the well-defined crystalline structures can be observed when fabricated at higher temperatures and longer periods of holding time.

This paper proposes a multi-objective Gannet Optimization Algorithm (MOGOA) to address the issue of unbalanced train occupancy rates in railway train operation planning. MOGOA employs an adaptive multi-population co-evolutionary strategy to balance exploration and exploitation, utilizing a non-dominated sorting algorithm based on crowding distance to select parent and child samples. These samples serve as initial solutions for subsequent iterations. A novel maximin fitness function guides the iterative update of the global optimal position. MOGOA is applied to the train operation planning problem with dynamic passenger flow allocation feedback. It collaboratively optimizes the number of train operations, sections, and stops to reduce costs, balance occupancy rates, minimize travel time, and enhance travel satisfaction. The practical applicability of MOGOA in optimizing train operation plans based on dynamic passenger flow allocation is significant.

ObjectiveThis randomized double-blinded clinical study is to investigate the clinical efficacy of per-paravertebral disk ozone injection combined with steroids in the treatment of patients with chronic discogenic low back pain (CDLBP).MethodsGroup A (N = 60) received a per-paravertebral injection of a steroid mixture of 10 mL with pure oxygen 20 mL, while group B (N = 60) received a per-paravertebral injection of a steroid mixture of 10 mL combined with ozone 20 mL (30 μg/mL). Injections were administered once a week for 3 weeks, with a follow-up of 6 months. Clinical outcomes were assessed at week 1, month 3, and month 6 with the help of Visual Analog Scale (VAS) scores and Macnab efficacy evaluation.ResultsThe VAS score of both group A (1.65 vs. 6.87, p = 0.000) and group B (1.25 vs. 6.85, p = 0.000) at week 1 was significantly reduced compared to baseline. The effect was sustained at the 3- and 6-month follow-up periods (p

Abstract Background This study was designed to compare early outcomes associated with coronary artery bypass grafting for multi-vessel disease conducted using either minimally invasive or conventional off-pump techniques. Methods From January 2017 through January 2021, 582 patients with multi-vessel lesion coronary artery disease underwent either minimally invasive cardiac surgery coronary artery bypass grafting (MICS CABG) or conventional off-pump coronary artery bypass grafting (OPCABG) treatment by our team at Anzhen Hospital. Patients in the MICS CABG group were propensity score-matched with those in the OPCABG at a 1:1 ratio (MICS CABG = 172; OPCABG = 172), using epidemiological data, preoperative clinical characteristics, and SYNTAX score as covariates. Perioperative outcomes and 6-month computed tomography angiography findings were compared between these groups. Results No significant differences between groups were observed with respect to 30-day postoperative mortality, myocardial infarction, and stroke incidence. Surgical data indicated that the MICS CABG procedure was able to cover all three main arterial territories with a relatively low need for circulatory assistance. The MICS CABG procedure was associated with a longer operative duration, but was also associated with higher postoperative hemoglobin and activities of daily living index values as well as a shorter duration of postoperative hospitalization (P

Background: Acetabular metastasis is a type of metastatic bone cancer, and it mainly metastasizes from cancers such as lung cancer, breast cancer, and renal carcinoma. Acetabular metastasis often causes severe pain, pathological fractures, and hypercalcemia which may seriously affect the quality of life of acetabular metastasis patients. Due to the characteristics of acetabular metastasis, there is no most suitable treatment to address it. Therefore, our study aimed to investigate a novel treatment technique to relieve these symptoms.Methods: Our study explored a novel technique to reconstruct the stability of the acetabular structure. A surgical robot was used for accurate positioning and larger-bore cannulated screws were accurately inserted under the robot’s guidance. Then, the lesion was curetted and bone cement was injected through a screw channel to further strengthen the structure and kill tumor cells.Results: A total of five acetabular metastasis patients received this novel treatment technique. The data relating to surgery were collected and analyzed. The results found that this novel technique can significantly reduce operation time, intraoperative bleeding, visual analogue score scores, Eastern Cooperative Oncology Group scores, and postoperative complications (e.g., infection, implant loosening, hip dislocation) after treatment. Follow-up time ranged from 3 months to 6 months, and the most recent follow-up results showed that all patients survived and no acetabular metastasis progressed in any of the patients after surgery.Conclusion: Surgical robot-assisted tripod percutaneous reconstruction combined with the bone cement filling technique may be a novel and suitable treatment in acetabular metastasis patients. Our study may provide new insights into the treatment of acetabular metastasis.

Plant communities in the Loess Plateau’s artificial afforestation forests play an important role in fragile ecosystem restoration. Therefore, the composition, coverage, biomass, diversity, and similarity of grassland plant communities in different years of artificial afforestation in cultivated land were investigated. The effects of years of artificial afforestation on grassland plant community succession in the Loess Plateau were also investigated. The results showed that as the number of years of artificial afforestation increased, grassland plant communities grew from scratch, constantly optimizing community components, improving community coverage, and increasing aboveground biomass. The community diversity index and similarity coefficient gradually approached those of a 10-year abandoned community that had recovered naturally. After 6 years of artificial afforestation, the dominant species of the grassland plant community changed from Agropyron cristatum to Kobresia myosuroides, and the main associated species changed from Compositae and Gramineae to Compositae, Gramineae, Rosaceae, and Leguminosae. The α-diversity index accelerated restoration, the richness index and diversity index increased, and the dominant index decreased. The evenness index had no significant difference from CK. The β-diversity index decreased as the number of years of afforestation increased. The similarity coefficient between CK and grassland plant communities in various lands changed from medium dissimilarity to medium similarity at 6 years of afforestation. According to the analysis of various indicators of the grassland plant community, the grassland plant community had a positive succession within 10 years of artificial afforestation on the cultivated land of the Loess Plateau, and the threshold of the years from slow to fast was 6 years.

Abstract Accumulating evidence has shown that circular RNA (circRNA) dysregulation is involved in various types of cancer, including osteosarcoma (OS). Nevertheless, the role and mechanism of circRNAs in OS progression and chemoresistance remain elusive. We found that a novel doxorubicin-induced circular RNA, hsa_circ_0004674, screened by whole total transcriptome RNA sequencing in our previous study, was upregulated in OS chemoresistant cell lines and tissues and also connected with patients’ poor prognosis. Circ_0004674 knockdown remarkably suppressed OS cell chemoresistance, proliferation, migration, invasion, OS tumor growth, and enhanced cell cycle arrest and apoptosis in vitro and in vivo through control the expression of the antiapoptotic protein MCL1, a member of the Bcl-2 gene family. Further online bioinformatics analysis revealed that miR-142-5p had potential binding sites that can bind circ_0004674 and the 3′UTR of MCL1 mRNA. Moreover, the expression and function of miR-142-5p were conversely correlated with circ_0004674 in vitro. RIP, pull-down, luciferase assay, and RNA FISH demonstrated that circ_0004674 could compete with MCL1 for miR-142-5p binding to counteract miR-142-5p-mediated repression of MCL1 at the post-transcriptional level. To sum up, our study sheds light on the critical role of the oncogenic circ_0004674/miR-142-5p/MCL1 axis in OS progression and chemoresistance, providing a novel potential target for OS therapy.

Abstract Heterocyclic compounds are representative of a larger class of organic compounds, and worthy of attention for many reasons, chief of which is the participation of heterocyclic scaffolds in the skeleton structure of many drugs. Lipases are enzymes with catalytic versatility, and play a key role in catalyzing the reaction of carbon–carbon bond formation, allowing the production of different compounds. This article reviewed the lipase-catalyzed aldol reaction, Knoevenagel reaction, Michael reaction, Mannich reaction, etc., in the synthesis of several classes of heterocyclic compounds with important physiological and pharmacological activities, and also prospected the research focus in lipase-catalyzed chemistry transformations in the future.

Abstract Background Brucellosis is a worldwide zoonotic infectious disease that is transmitted in various ways and causes great harm to humans and animals. The brucellosis pathogen is Brucella, which mainly resides in macrophage cells and survives and replicates in host cells. However, the mechanisms underlying Brucella survival in macrophage cells have not been thoroughly elucidated to date. Peroxiredoxin 6 (Prdx6) is a bifunctional protein that shows not only GSH peroxidase activity but also phospholipase A2 activity and plays important roles in combating oxidative damage and regulating apoptosis. Results Recombinant mouse (Mus musculus) Prdx6 (MmPrdx6) was expressed and purified, and monoclonal antibodies against MmPrdx6 were prepared. Using the Brucella suis S2 strain to infect RAW264.7 murine macrophages, the level of intracellular Prdx6 expression first decreased and later increased following infection. Overexpressing Prdx6 in macrophages resulted in an increase in B. suis S2 strain levels in RAW264.7 cells, while knocking down Prdx6 reduced the S2 levels in cells. Conclusions Host Prdx6 can increase the intracellular survival of B. suis S2 strain and plays a role in Brucella infection.

Objectives. Minimally invasive coronary artery bypass grafting (MICS CABG) has emerged as an alternative treatment for patients with multi-vessel coronary artery disease, but there are certain surgical challenges inherent in the adoption of this approach. The present study was conducted to provide insight regarding the outcomes associated with our first 118 cases, to discuss the surgical difficulties encountered in these patients, and to outline the potential countermeasures. Methods. Between January 2017 and January 2020, 118 patients underwent multi-vessel MICS CABG. These patients were stratified into two groups based upon whether they did or did not experience surgical challenges, and early clinical outcomes were compared between these groups to assess the incidence of technical difficulties and associated factors. Results. Surgical challenges arose in 38 of the 118 cases in this study, including 13 cases of exposure-related difficulties, 11 cases of proximal anastomosis-related difficulties, 15 cases of distal anastomosis-related difficulties, 4 cases of LITA-related difficulties, and 3 cases of lung-related difficulties. Relative to the other 80 patients, those patients for whom intraoperative technical challenges arose experience significant increases in operative duration (4.94 ± 0.89 vs. 5.59 ± 1.11 h, P=0.001), intraoperative blood loss (667 ± 313 vs. 892 ± 532 mL, P=0.005), length of the ICU admission (17.59 ± 3.51 vs. 22.59 ± 17.31 h, P=0.015), and the duration of postoperative hospitalization (5.96 ± 1.23 vs. 6.71 ± 1.92 days, P=0.012). There were no significant differences between these groups with respect to the mean graft number, major complications such as stroke or organ dysfunction, or one-year graft patency. Conclusions. There is a substantial learning curve associated with performing off-pump MICS CABG to treat multi-vessel disease. Surgical challenges encountered during this procedure may increase the operative duration, intraoperative blood loss, ICU admission, and the duration of postoperative hospitalization. However, these issues do not appear to compromise the efficacy of complete revascularization, and early clinical outcomes associated with this procedure remain acceptable.

Background/Aims: Heat stress could cause huge losses for Lentinula edodes in China and other Asian cultivation areas. Yet our understanding of mechanism how to defend to heat stress is incomplete. Methods: Using heat-tolerant and heat-sensitive strains of L. edodes, we reported a combined proteome and transcriptome analysis of L. edodes response to 40 °C heat stress for 24 h. Meanwhile, the effect of LeDnaJ on the thermotolerance and IAA (indoleacetic acid) biosynthesis in L. edodes was analyzed via the over-expression method. Results: The proteome results revealed that HSPs (heat shock proteins) such as Hsp40 (DnaJ), Hsp70, Hsp90 and key enzymes involved in tryptophan and IAA metabolism process LeTrpE, LeTrpD, LeTam-1, LeYUCCA were more highly expressed in S606 than in YS3357, demonstrating that HSPs and tryptophan as well as IAA metabolism pathway should play an important role in thermotolerance. Over-expression of LeDnaJ gene in S606 strains showed better tolerance to heat stress. It was also documented that intracellular IAA accumulation of S606 (8-fold up) was more than YS3357 (2-fold up), and exogenous IAA enhanced L. edodes tolerance to heat stress. Conclusion: Our data support the interest of LeTrpE, LeDnaJ, tryptophan and IAA could play a pivotal role in enhancing organism thermotolerance.

Chemoresistance has been an obstacle in the further improvement of 5‐year survival rates of osteosarcoma (OS) patients, but the underlying mechanism of chemo‐resistance remains unclear. A comprehensive analysis of mRNAs and noncoding RNAs related to OS chemo‐resistance could help solve this problem. In the current study, we first identified that fibronectin‐1 (FN1), screened by microarray analysis in three paired chemo‐resistant and chemo‐sensitive OS cell lines, was significantly upregulated in the chemo‐resistant OS cell lines and tissues and was related to unfavourable prognosis. Further functional assays revealed that FN1 inhibition greatly increased the sensitivity of OS cells to doxorubicin in vitro and in vivo, whereas FN1 overexpression had the opposite effect. Moreover, mechanistic investigation demonstrated, by a series of assays that included luciferase reporter gene, RNA immunoprecipitation, RNA pull‐down and rescue assays, that FN1 expression was regulated by the oncogenic long noncoding RNA (lncRNA) OIP5‐AS1 through sponging miR‐200b‐3p. Thus, these results indicated the role and potential application of the lncRNA OIP5‐AS1/miR‐200b‐3p/FN1 regulatory pathway as a promising target in treatment of OS chemo‐resistance. First report about expression, function and potential clinical significance of fibronectin‐1 (FN1), miR‐200b‐3p, lncRNA OIP5‐AS1 in osteosarcoma (OS) doxorubicin resistance; Regulatory mechanism of FN1 expression was identified and lncRNA OIP5‐AS1/miR‐200b‐3p/FN1 regulatory pathway was first constructed in OS doxorubicin resistance. [ABSTRACT FROM AUTHOR]

A 52-year-old man was diagnosed with general paresis, whose HIV antibodies were negative. After initiation of treatment with penicillin on the first day, no obvious clinical Jarisch-Herxheimer reaction was found. However, 6 days after treatment, the patient was found more irritable and was unable to fall asleep at night. On the seventh day, worsened magnetic resonance imaging (MRI) abnormalities in the bilateral medial and anterior temporal lobes were unexpectedly discovered. These worsened MRI abnormalities improved quickly after the addition of dexamethasone treatment. We consider that these transient and slight mental symptoms may be associated with the transiently worsening phenomenon in cerebral MRI findings during the early period of treatment with penicillin. This indicates that some nonspecific inflammatory process has happened in the early stage of treatment, which necessitates the use of corticosteroids after the occurrence of systemic or mental symptoms. [ABSTRACT FROM AUTHOR]

High-brightness tapered lasers with photonic crystal structures are designed and fabricated. A narrow taper angle is designed for the tapered section. The device delivers an output power of 3.3 W and a maximum wall-plug efficiency of 43%. The vertical beam divergence is around 11° at different currents. Nearly diffraction-limited beam qualities for the vertical and lateral directions are obtained. The lateral beam quality factor M 2 is below 2.5 and the vertical M 2 value is around 1.5 across the whole operating current range. The maximum brightness is 85 MW·cm−2sr−1. When the current is above 3.3 A, the brightness is still above 80 MW·cm−2sr−1. [ABSTRACT FROM AUTHOR]

The coupling efficiency of the beam combination and the fiber-coupled module is limited due to the large vertical divergent angle of conventional semiconductor laser diodes. We present a high coupling efficiency module using photonic-band-crystal (PBC) laser diodes with narrow vertical divergent angles. Three PBC single-emitter laser diodes are combined into a fiber with core diameter of 105 μm and numerical aperture of 0.22. A high coupling efficiency of 94.4% is achieved and the brightness is calculated to be 1.7 MW/(cmsr) with the injection current of 8 A. [ABSTRACT FROM AUTHOR]

A two-dimensional chiral structure with an h-shape and H-shape on opposing sides of a dielectric layer is proposed that can realize simultaneously dual-band asymmetric transmission of linearly and circularly polarized waves in the near-infrared band. Meanwhile, the structure realizes a maximum asymmetric transmission of 0.56 and 0.30 for linearly and circularly polarized waves, respectively, at the resonant frequency. These results have been analyzed with simulations in detail. The physical mechanism of linearly and circularly polarized wave transmission and conversion based on current distribution and electric fields is also investigated. [ABSTRACT FROM AUTHOR]