Cascaded metasurfaces for high-purity vortex generation.

We introduce a new paradigm for generating high-purity vortex beams with metasurfaces. By applying optical neural networks to a system of cascaded phase-only metasurfaces, we demonstrate the efficient generation of high-quality Laguerre-Gaussian (LG) vortex modes. Our approach is based on two metasurfaces where one metasurface redistributes the intensity profile of light in accord with Rayleigh-Sommerfeld diffraction rules, and then the second metasurface matches the required phases for the vortex beams. Consequently, we generate high-purity LGp,l optical modes with record-high Laguerre polynomial orders p = 10 and l = 200, and with the purity in p, l and relative conversion efficiency as 96.71%, 85.47%, and 70.48%, respectively. Our engineered cascaded metasurfaces suppress greatly the backward reflection with a ratio exceeding -17 dB. Such higher-order optical vortices with multiple orthogonal states can revolutionize next-generation optical information processing.

The Prognostic Value of PERK in Cancer and Its Relationship With Immune Cell Infiltration.

Background: Protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK) is a type I transmembrane protein that functions as an endoplasmic reticulum (ER) stress sensor to regulate global protein synthesis. Recent research studies suggest that PERK, as an important receptor protein of unfolded protein response, is involved in the pathogenesis of many cancers. This study aimed to investigate PERK expression and its relationship with prognosis in pan-cancer and attempted to explore the relevant mechanism of PERK involved in the regulation of cancer pathogenesis. Methods: The Oncomine and TIMER databases were used to analyze the expression of PERK between pan-cancer samples and normal samples. Survival analysis was performed using the PrognoScan, Kaplan-Meier (K-M) plotter, and UALCAN databases. Gene set enrichment analysis (GSEA) was used to perform the functional enrichment analysis of the PERK gene in breast invasive carcinoma (BRCA), head and neck squamous cell carcinoma (HNSC), and thyroid carcinoma (THCA). The TIMER database was used to investigate the correlation between PERK expression and tumor-infiltrating immune cells and analyze the relationship of PERK with marker genes of immune cells which were downloaded from the CellMarker database in BRCA, HNSC, and THCA. Results: PERK was differentially expressed in various cancers, such as breast cancer, liver cancer, lung cancer, gastric carcinoma, lymphoma, thyroid cancer, leukemia, and head and neck squamous cell carcinomas. The high expression of PERK was associated with a poor prognosis in KIRP, LGG, BRCA, and THCA and with a favorable prognosis in HNSC. The results of GSEA indicated that PERK was mainly enriched in immune-related signaling pathways in BRCA, HNSC, and THCA. Moreover, PERK expression was significant positively correlated with infiltrating levels of macrophages and dendritic cells and was strongly associated with a variety of immune markers, especially macrophage mannose receptor 1 (MRC1, also called CD206) and T-helper cells (Th). Conclusion: The high expression of PERK could promote the infiltration of multiple immune cells in the tumor microenvironment and could deteriorate the outcomes of patients with breast and thyroid cancers, suggesting that PERK as well as tumor-infiltrating immune cells could be taken as potential biomarkers of prognosis.

Architecture and Electrochemical Performance of Alkynyl-Linked Naphthyl Carbon Skeleton: Naphyne.

The synthesis of new sp-hybridized carbon allotropes is a meaningful and challenging issue. Among the alkynyl carbon family, polyaromatic alkynes is a new branch to be developed. Herein, naphyne with a frame construction of alkynyl-linked naphthyl skeleton was efficiently fabricated through targeted mechanochemical reaction of calcium carbide and perchloronaphthalene. Its unique property and structure with wide alkynyl-naphthyl conjugation, multilayered nanofilm morphology, and high structural stability were corroborated by the comprehensive characterizations combined with computational simulations. Because of these structural features, the as-prepared naphyne can be applied as high-performance binder-free supercapacitor electrode with high specific capacitance (154 F g-1), robust long-term retention (92.1% after 5000 cycles), and prominent electrical conductivity (1490 S m-1). The successful architecture of naphyne approves the feasible synthesis of polyaromatic alkynes and further may provide a prospective approach for the development of alkynyl carbon materials.

Synthesis and Zn(II) modification of hierarchical porous carbon materials from petroleum pitch for effective adsorption of organic dyes.

The discovery of efficient carbonaceous adsorbents for the removal of organic dyes is a meaningful subject. In this study, hierarchical porous carbon materials (HPCMs) were synthesized from petroleum pitch through template strategy coupled with in-situ chemical activation, and the optimal HPCM was further modified by Zn(II) to get modified HPCM (MHPCM). Their properties and structures were characterized, and their adsorption performances for two typical dyes, methylene blue (MB) and direct black 38 (DB 38), were examined. The as-prepared HPCMs and MHPCM exhibit high specific surface area with hierarchical pore structure, abundant oxygen-containing group, and distinct layered structure. As an adsorbent for dye removals, the MHPCM shows excellent performance with its Langmuir saturated adsorption capacity being 1585.7 and 438.6 mg/g for MB and DB 38, respectively. This is mainly due to the large surface area and hierarchical pore structure of HPCMs, as well as the modification effect of Zn(II). This work provides an efficient strategy for the synthesis of carbonaceous adsorbents used in the adsorptive removal of different molecular size dyes, as well as a new approach for the valuable use of low-cost petroleum pitch.