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To meet the growing demand for photonic integration and device miniaturization, planar diffractive Fresnel zone plates (FZPs) are widely applied in integrated optical systems. However, challenges remain in fabricating FZPs with high efficiency and satisfying the requirement for cross-scale fabrication. This paper details a high efficiency method for fabricating ultrathin FZPs of different scales on metal films by using holographic femtosecond lasers. The FZPs are split into a series of element patterns that are printed in order by using corresponding modulated femtosecond pulses. The fabricated FZPs are spliced by the printed element structures with no FZP size limitation in theory. FZPs with an area varying across three orders of magnitude are presented to demonstrate the capability of cross-scale fabrication. The fabricated FZPs possess an excellent broadband focusing and imaging ability in the visible spectrum. Furthermore, the fabrication of other functional ultrathin lenses, such as axial multifocal zone plates, petal-like zone plates, and FZP arrays, is described, revealing the wide potential for the flexible and scalable fabrication method in on-chip integrated optical systems.

Vibration mixing, characterized by the high-frequency vibrations of the mixing shaft, can enhance the mechanical properties of ultra-high-performance concrete (UHPC). However, the effects of vibration mixing on carbon nanotube (CNT)-reinforced UHPC have not been previously reported. To investigate the impact of vibration mixing on the properties of CNT-reinforced UHPC, a comparative study was conducted using different vibration mixing durations and twin-shaft mixing. The results indicate that for CNT-reinforced UHPC, vibration mixing achieves better flowability, higher wet apparent density, and superior mechanical properties in shorter mixing times compared to twin-shaft mixing, making it a more favorable method. Considering vibration mixing times ranging from 3 to 7 min, the optimal time was found to be 3 min, during which the axial compressive strength increased by 3.3%, the elastic limit tensile strength and tensile strength improved by 14.6% and 15.8%, respectively, and the initial cracking strength and flexural strength increased by 12.6% and 13.4%, respectively, compared to values after 10 min of twin-shaft mixing. [ABSTRACT FROM AUTHOR]

In this study, we report the formation of laser-induced periodic surface nanometric concentric ring structures on silicon surfaces through single-spot irradiation with orthogonally polarized femtosecond laser double-pulse sequences (OP pulses). The period of the ring structures is marginally smaller than the irradiated laser’s wavelength, which indicates that the structures are a type of low-spatial-frequency laser-induced periodic surface structures. Regular nanometric concentric ring structures can be formed when the time delay between two subpulses is approximately 1 ps (roughly from 500 fs to 1.5 ps) and the number of laser bursts is approximately 4. The formation mechanism of the concentric ring structures is attributed to the surface wave (i.e., cylindrical wave) stimulated by OP pulses through single-spot irradiation is radially distributed. Large area of concentric ring structures eliminating anisotropy in the generation of structural colors was shown in this paper.

To improve the efficiency of femtosecond laser direct writing, holographic femtosecond laser patterning using spatial light modulators has been widely used for the processing of micro/nanopatterns. However, the speckle noise of modulated optical fields severely limits the quality of fabricated patterns. We present a simple and effective method which involves interlacing a target pattern into a series of target subpatterns that consist of spaced spots to solve this problem. The separation of spots weakens the random interference between adjacent spots of optical fields, so the speckle noise reduces effectively, which improves the uniformity of the modulated optical fields and makes the fabricated patterns with high quality. With optimal interlacing numbers, complex micropattern arrays containing curved edges and sophisticated structures can be fabricated with superior quality and high efficiency. Binary holograms with improved optical characterization are realized by using the interlacing-pattern method, revealing the extensive potential of this method in micropattern processing and functional device fabrication with high quality and efficiency.

It has been reported that ubiquitin-conjugating enzyme 9 (Ubc9),the unique enzyme2 in the sumoylation pathway, is up-regulatedin many cancers. However, the expression and regulation ofUBC9 in glioma remains unknown. In this study, we found thatUbc9 was up-regulated in glioma tissues and cell lines comparedto a normal control. UBC9 knockdown by small interfering RNA(siRNA) affected cell proliferation and apoptosis in T98G cells.Further experiments revealed that microRNA (miR)-214 directlytargeted the 3' untranslated region (UTR) of UBC9 and that therewas an inverse relationship between the expression levels ofmiR-214 and UBC9 protein in glioma tissues and cells. miR-214overexpression suppressed the endogenous UBC9 protein andaffected T98G cell proliferation. These findings suggest thatmiR-214 reduction facilitates UBC9 expression and is involvedin the regulation of glioma cell proliferation

Protein arginine methyltransferase 1 (PRMT1), a type-I argininemethyltransferase, has been implicated in diverse cellularevents. We have focused on the role of PRMT1 in gliomagenesis.In this study, we showed that PRMT1 expression wasup-regulated in glioma tissues and cell lines compared withnormal brain tissues. The knock-down of PRMT1 resulted in anarrest in the G1-S phase of the cell cycle, proliferation inhibitionand apoptosis induction in four glioma cell lines(T98G, U87MG, U251, and A172). Moreover, an in vivo studyconfirmed that the tumor growth in nude mouse xenografts wassignificantly decreased in the RNAi-PRMT1 group. Additionally,we found that the level of the asymmetric dimethylatedmodification of H4R3, a substrate of PRMT1, was higher inglioma cells than in normal brain tissues and decreased afterPRMT1 knock-down. Our data suggest a potential role forPRMT1 as a novel biomarker of and therapeutic target ingliomas.

Titanium dioxide (TiO 2 ) is one of the most promising candidates for photoelectrochemistry applications. For a high photoelectrochemistry performance, the control of crystal structure and crystal facet is essential. The phase transformation of TiO 2 is conventionally achieved by thermal annealing. Here, we report an approach for selective phase transformation of TiO 2 containing exposed reactive facets with improved photoelectrochemistry performance. After femtosecond laser processing, TiO 2 nanotubes with exposed reactive anatase {010} facets are prepared, and they have a maximum photocurrent density more than 5 times that of pure anatase. Additionally, this strategy can induce phase transformation in a selective area, which shows the advantages of patterning processing. Our method constructs a promising strategy for preparing functional nanomaterials with high performances and functionality.