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In this article, we propose hybrid precoding/combining designs for full-duplex amplify-and-forward millimeter wave relay systems. The imperfect channel estimations induced by applicable estimation techniques are considered to develop robust fully digital transceivers. A zero-space self-interference (SI) cancellation method is proposed to attenuate the SI. An alternating method with closed-form solutions is utilized to solve the hybrid processors. Simulation results show that the proposed design is close to the fully digital solutions and prevails the existing designs.

BackgroundDespite much improvement in the treatment for acute lymphoblastic leukemia (ALL), childhood ALLs with MLL-rearrangement (MLL-r) still have inferior dismal prognosis. Thus, defining mechanisms underlying MLL-r ALL maintenance is critical for developing effective therapy.MethodsGSE13159 and GSE28497 were selected via the Oncomine website. Differentially expressed genes (DEGs) between MLL-r ALLs and normal samples were identified by R software. Next, functional enrichment analysis of these DEGs were carried out by Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Set Enrichment Analysis (GSEA), and Search Tool for the Retrieval of Interacting Genes/Proteins (STRING). Then, the key hub genes and modules were identified by Weighted Gene Co-expression Network Analysis (WGCNA). Therapeutically Applicable Research to Generate Effective Treatments (TARGET) ALL (Phase I) of UCSC Xena analysis, qPCR, and Kaplan-Meier analysis were conducted for validating the expression of key hub genes from bone marrow cells of childhood ALL patients or ALL cell lines.ResultsA total of 1,045 DEGs were identified from GSE13159 and GSE28497. Through GO, KEGG, GSEA, and STRING analysis, we demonstrated that MLL-r ALLs were upregulating “nucleosome assembly” and “B cell receptor signal pathway” genes or proteins. WGCNA analysis found 18 gene modules using hierarchical clustering between MLL-r ALLs and normal. The Venn diagram was used to filter the 98 hub genes found in the key module with the 1,045 DEGs. We identified 18 hub genes from this process, 9 of which were found to be correlated with MLL-r status, using the UCSC Xena analysis. By using qPCR, we validated these 9 hub key genes to be upregulated in the MLL-r ALLs (RS4;11 and SEM) compared to the non-MLL-r ALL (RCH-ACV) cell lines. Three of these genes, BCL11A, GLT8D1 and NCBP2, were shown to be increased in MLL-r ALL patient bone marrows compared to the non-MLL-r ALL patient. Finally, Kaplan–Meier analysis indicated that childhood ALL patients with high BCL11A expression had significantly poor overall survival.ConclusionThese findings suggest that upregulated BCL11A gene expression in childhood ALLs may lead to MLL-r ALL development and BCL11A represents a new potential therapeutic target for childhood MLL-r ALL.

The epoxidation of olefins is strongly exothermic, which not only impacts negatively on the epoxide selectivity and catalytic stability, but also threatens safety in manufacturing processes. With the aim of accelerating the removal of exothermic heat, TS-1 extrudates were prepared by introducing different substances with high heat conductive rates (carborundum, copper and iron) to the extrusion mixture. The catalysts were characterized and used to catalyze 1-butene epoxidation in a fixed-bed reactor. Compared to traditional extruded catalysts, the new catalysts exhibit outstanding high stability, due to the inhibition of side reactions by rapid removal of exothermic heat. The influence of each additive content on the catalytic performance was studied. Furthermore, the relationship between the heat conductivity of the catalyst and the stability for 1-butene epoxidation was established. It shows that a higher heat conductivity leads to better stability of the catalyst. This work paves a new way for improving the stability of strong exothermic reactions.

Light detection and ranging (LiDAR) technologies, the active imaging technology, show a great potential in applications like threedimensional imaging. Combined with the frequency-modulated continuous-wave (FMCW) technology, LiDAR can provide the velocity of the target based on the Doppler effect. The linearization of the laser frequency sweep is crucial for higher resolution and lower signalto-noise ratio in FMCW LiDAR. In this paper, a proportional integral derivative (PID) control method based on a back propagation (BP) neural network is used to pre-calibrate the DFB laser to realize the high-linearity frequency sweep. The laser sweeping frequency is 12.5 kHz with a laser frequency excursion of 3.7 GHz, and the residual nonlinearity is 0.0015%. The linearized DFB laser is applied to the FMCW LiDAR system for two-dimensional imaging with a maximum distance of 70 meters.