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关键词： Antigen processing and presentation   MAIT   MR1   T-cell receptor  

摘要： MHC-related protein 1 (MR1) presents microbial riboflavin metabolites to mucosal-associated invariant T (MAIT) cells for surveillance of microbial presence. MAIT cells express a semi-invariant T-cell receptor (TCR), which recognizes MR1-antigen complexes in a pattern-recognition-like manner. Recently, diverse populations of MR1-restricted T cells have been described that exhibit broad recognition of tumor cells and appear to recognize MR1 in association with tumor-derived self-antigens, though the identity of these antigens remains unclear. Here, we have used TCR gene transfer and engineered MR1-expressing antigen-presenting cells to probe the MR1 restriction and antigen reactivity of a range of MR1-restricted TCRs, including model tumor-reactive TCRs. We confirm MR1 reactivity by these TCRs, show differential dependence on lysine at position 43 of MR1 (K43) and demonstrate competitive inhibition by the MR1 ligand 6-formylpterin. TCR-expressing reporter lines, however, failed to recapitulate the robust tumor specificity previously reported, suggesting an importance of accessory molecules for MR1-dependent tumor reactivity. Finally, MR1-mutant cell lines showed that distinct residues on the alpha 1/alpha 2 helices were required for TCR binding by different MR1-restricted T cells and suggested central but distinct docking modes by the broad family of MR1-restricted alpha beta TCRs. Collectively, these data are consistent with recognition of distinct antigens by diverse MR1-restricted T cells.

关键词： 3-D printing   millimeter-wave   differential feed   dual-polarized antenna array   magnetoelectric (ME) dipole   wideband  

摘要： A millimeter-wave high-gain dual-polarized antenna array with an enhanced bandwidth is presented. An innovative air-filled differential feeding cavity loaded with a short-ended cross-shaped waveguide is investigated to serve as the feed network and the mode splitter simultaneously of the 2 x 2 dual-polarized subarrays. Wideband characteristics and a compact planar size that are desirable for the wideband array design are achieved. Moreover, a wideband dual-polarized waveguidefed magnetoelectric (ME) dipole antenna with a lightweight self-support geometry and wideband H-plane parallel feed networks with modified dual-layered configurations are proposed, which are convenient to connect with the differential feeding cavity directly. With the use of a commercial metallic 3-D printing facility, the proposed radiating elements, feeding cavities, and feed networks can be combined successfully in a whole piece with a lightweight geometry. The printed 8 x 8 array prototype operating in the Ka-band confirms a wide bandwidth of about 30%, a gain of up to 28.5 dBi, and stable unidirectional radiation patterns for the two polarizations. Benefitted from the advantages of the promising wideband dual-polarized radiations and convenience of fabrication, the proposed antenna array would be attractive for millimeter-wave polarization diversity applications.

关键词： airflow vector sensor   differential pressure sensor   drone stability  

摘要： This paper presents an airflow vector sensor for drones. Drones are expected to play a role in various industrial fields. However, the further improvement of flight stability is a significant issue. In particular, compact drones are more affected by wind during flight. Thus, it is desirable to detect air current directly by an airflow sensor and feedback to the control. In the case of a drone in flight, the sensor should detect wind velocity and direction, particularly in the horizontal direction, for a sudden crosswind. In addition, the sensor must also be small, light, and highly sensitive. Here, we propose a compact spherical airflow sensor for drones. Three highly sensitive microelectromechanical system (MEMS) differential pressure (DP) sensor chips were built in the spherical housing as the sensor elements. The 2D wind direction and velocity can be measured from these sensor elements. The fabricated airflow sensor was attached to a small toy drone. It was demonstrated that the sensor provided an output corresponding to the wind velocity and direction when horizontal wind was applied via a fan while the drone was flying. The experimental results demonstrate that the proposed sensor will be helpful for directly measuring the air current for a drone in flight.

关键词： adrenocortical carcinoma   adenoma   adrenal   tissue   microRNA   biomarker   artificial intelligence   neural network  

摘要： Simple Summary The histological differential diagnosis of adrenocortical adenoma and carcinoma is difficult and requires great expertise. MiRNAs were shown to be useful for the differential diagnosis of benign and malignant tumors of several organs, and several findings have suggested their utility in adrenocortical tumors as well. Here, we have selected tissue miRNAs based on the literature search, and used machine learning to identify novel clinically applicable miRNA combinations. Combinations with high sensitivity and specificity (both over 90%) have been identified that could be promising for clinical use. Besides being a useful adjunct to histological examination, these miRNA combinations could enable preoperative adrenal biopsy in patients with adrenal tumors suspicious for malignancy. The histological analysis of adrenal tumors is difficult and requires great expertise. Tissue microRNA (miRNA) expression is distinct between benign and malignant tumors of several organs and can be useful for diagnostic purposes. MiRNAs are stable and their expression can be reliably reproduced from archived formalin-fixed, paraffin-embedded (FFPE) tissue blocks. Our purpose was to assess the potential applicability of combinations of literature-based miRNAs as markers of adrenocortical malignancy. Archived FFPE tissue samples from 10 adrenocortical carcinoma (ACC), 10 adrenocortical adenoma (ACA) and 10 normal adrenal cortex samples were analyzed in a discovery cohort, while 21 ACC and 22 ACA patients were studied in a blind manner in the validation cohort. The expression of miRNA was determined by RT-qPCR. Machine learning and neural network-based methods were used to find the best performing miRNA combination models. To evaluate diagnostic applicability, ROC-analysis was performed. We have identified three miRNA combinations (hsa-miR-195 + hsa-miR-210 + hsa-miR-503;hsa-miR-210 + hsa-miR-375 + hsa-miR-503 and hsa-miR-210 + hsa-miR-483-5p + hsa-miR-503) as unexpectedly good p

关键词： Biomedicine   general   Immunology   Allergology   Antibodies   Gastroenterology  

摘要： Fibroblasts mediate tissue remodeling in eosinophilic esophagitis (EoE), a chronic allergen-driven inflammatory pathology. Diverse fibroblast subtypes with homeostasis-regulating or inflammatory profiles have been recognized in various tissues, but which mediators induce these alternate differentiation states remain largely unknown. We recently identified that TNFSF14/LIGHT promotes an inflammatory esophageal fibroblast in vitro. Herein we used esophageal biopsies and primary fibroblasts to investigate the role of the LIGHT receptors, herpes virus entry mediator (HVEM) and lymphotoxin-beta receptor (LT beta R), and their downstream activated pathways, in EoE. In addition to promoting inflammatory gene expression, LIGHT down-regulated homeostatic factors including WNTs, BMPs and type 3 semaphorins. In vivo, WNT2B(+) fibroblasts were decreased while ICAM-1(+) and IL-34(+) fibroblasts were expanded in EoE, suggesting that a LIGHT-driven gene signature was imprinted in EoE versus normal esophageal fibroblasts. HVEM and LT beta R overexpression and deficiency experiments demonstrated that HVEM regulates a limited subset of LIGHT targets, whereas LT beta R controls all transcriptional effects. Pharmacologic blockade of the non-canonical NIK/p100/p52-mediated NF-kappa B pathway potently silenced LIGHT's transcriptional effects, with a lesser role found for p65 canonical NF-kappa B. Collectively, our results show that LIGHT promotes differentiation of esophageal fibroblasts toward an inflammatory phenotype and represses homeostatic gene expression via a LT beta R-NIK-p52 NF-kappa B dominant pathway.

摘要： BACKGROUND: Secondary organic aerosols (SOAs) formed from anthropogenic or biogenic gaseous precursors in the atmosphere substantially contribute to the ambient fine particulate matter [PM <2.5 mu m in aerodynamic diameter (PM2.5)] burden, which has been associated with adverse human health effects. However, there is only limited evidence on their differential toxicological impact. OBJECTIVES: We aimed to discriminate toxicological effects of aerosols generated by atmospheric aging on combustion soot particles (SPs) of gaseous biogenic (fl-pinene) or anthropogenic (naphthalene) precursors in two different lung cell models exposed at the air-liquid interface (ALI). METHODS: Mono- or cocultures of lung epithelial cells (A549) and endothelial cells (***926) were exposed at the ALI for 4 h to different aerosol concentrations of a photochemically aged mixture of primary combustion SP and fl-pinene (SOAflPIN-SP) or naphthalene (SOANAP-SP). The internally mixed soot/SOA particles were comprehensively characterized in terms of their physical and chemical properties. We conducted toxicity tests to determine cytotoxicity, intracellular oxidative stress, primary and secondary genotoxicity, as well as inflammatory and angiogenic effects. RESULTS: We observed considerable toxicity-related outcomes in cells treated with either SOA type. Greater adverse effects were measured for SOANAP-SP compared with SOAflPIN-SP in both cell models, whereas the nano-sized soot cores alone showed only minor effects. At the functional level, we found that SOANAP-SP augmented the secretion of malondialdehyde and interleukin-8 and may have induced the activation of endothelial cells in the coculture system. This activation was confirmed by comet assay, suggesting secondary genotoxicity and greater angiogenic potential. Chemical characterization of PM revealed distinct qualitative differences in the composition of the two secondary aerosol types. DISCUSSION: In this study using A549 and ***926 ce

关键词： 非线性方程-常微分方程-高等学校-教材  

ISBN: (纸本)9787030714886

摘要： 研究生微分方程核心课教材，常微分方程定性理论的入门教材，介绍非线性常微分方程的近代方法,并兼顾某些应用.这是常微分方程定性理论的入门教材，是从事常微分方程、动力系统和非线性科学与数学物理、力学、非线性振动及复杂系统理论等交叉学科研究方向的基础性教材。全书篇幅简短，理论扎实，适合多层级数学教学，还有多幅精心绘制的波形图，形象生动便于理解，适合本方向学习。——网友……

关键词： BDS WADS   pseudorange bias   spp   integrity  

摘要： Due to satellite signal deformations, there are different constant biases in the same satellite signal that are measured by different technical types of receivers and different satellite signals that are measured by the same type of receiver, which are named pseudorange biases. These biases cannot be transmitted to users with existing navigation parameters, such as satellite time group delay (TGD) and receiver differential code biases (DCB). With the improvement of the signal-in-space accuracy of the Global Navigation Satellite System (GNSS), the pseudorange bias has become one of the primary error sources affecting the accuracy of GNSS services. To ensure the accuracy for users under the wide area differential services (WADS), we extracted the pseudorange biases of Beidou Satellite Navigation System (BDS) B1I, B3I and B1I/B3I signals and analyzed the impact of those biases on users under the WADS. Finally, we tried to eliminate this influence. The results show that the pseudorange biases of the B3I signal are smaller than those of the B1I signal at the centimeter level, but the pseudorange biases of the B1I/B3I signal can reach the meter level. Due to the large pseudorange bias of the B1I/B3I signal, the average user equivalent ranging error (UERE) under the WADS is 1.19 m, which is no better than the average UERE under open services (OS). Influenced by the pseudorange biases, the average positioning accuracies of the B1I/B3I signal are 4.17 m and 4.24 m under the WADS and the OS. When the pseudorange biases are deducted, these accuracies are 3.03 m and 3.50 m, respectively.

关键词： Feedback control   Markov processes   Control systems   Delays   Asymptotic stability   Stability criteria   Symmetric matrices   Brownian motion   delay feedback control   Markov chain   stability in distribution  

摘要： This article is concerned with the design of a feedback control based on past states in order to make a given unstable hybrid stochastic differential equation (SDE) to be stable in distribution (stabilization in distribution). This is the first article in this direction. Under the global Lipschitz condition on the coefficients of the given unstable hybrid SDE, we will show that the stabilization in distribution can be achieved by linear delay feedback controls. In particular, we discuss how to design feedback controls in two structure cases: state feedback and output injection.

关键词： Probes   Baluns   Sensitivity   Couplings   Inductors   Radio frequency   Microstrip   Balun   common-mode rejection ratio (CMRR)   differential dual loop (DDL)   high sensitivity   magnetic field probe   near-field measurement  

摘要： In this communication, a magnetic field probe with high common-mode rejection ratio (CMRR) and high sensitivity for the near-field measurement is proposed, fabricated, and calibrated. The proposed magnetic field probe consists of a differential dual loop (DDL) to improve the CMRR to the electric field, a balun to convert the differential end to the single end, and a two-stage amplifier achieving proper gain to further enhance the sensitivity. The sensitivity of the probe is raised by more than 50 dB at 30 MHz compared with the reference probes. The measured CMRR is more than 40 dB from 200 kHz to 1 GHz. The measurements of the passive circuits are conducted, and validating that the sensitivity of the proposed probe is significantly improved.