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Metasurfaces are considered the most promising technologies for holographic imaging applications due to their exceptional optical properties and capabilities. However, the work on terahertz (THz) metasurface holographic imaging is relatively limited. Here, we propose a THz dielectric geometric-propagation phase metasurface that can operate in dual modes (reflection and transmission) and enable reconfigurable multifunctional holographic imaging. The dual-mode operation is realized by controlling the Fermi energy level (Ef) of the graphene integrated into the metasurface unit, and the reconfigurable three-channel holographic imaging in reflection or transmission mode are achieved by switching the feed polarization among left-handed circular polarization (LCP), right-handed circular polarization (RCP), and linear polarization (LP). The metasurface is designed based on the transmission mode, and a physical model for switching to the reflection mode is established. For the first time, to the best of our knowledge, a reflection–transmission dynamic modulation THz holographic imaging metasurface has been developed. The holographic metasurface operates in transmission mode at Ef = 0.1 eV and in reflection mode at Ef = 0.9 eV. Compared with recently published holographic imaging metasurfaces, the proposed metasurface offers the following advantages: high holographic efficiencies (42.5% to 49%), more holographic imaging channels, dynamic modulation dual-mode operations, and reconfigurability. The simulation results match the theory.

(1) Background: Ganoderic acids (GAs) are specific triterpenes of Ganoderma lucidum. The HPLC fingerprint profile of GAs of the fruiting body is well known, but their mycelial fingerprinting remains unclear. (2) Methods: An ethanol extract of the mycelium of G. lucidum (YK-01) was further purified via preparative HPLC. The triterpenoid compositions for four strains of G. lucidum and one strain of G. formosanum (purple lingzhi) were analyzed using HPLC. (3) Results: Nineteen lanostane triterpenes, including five new triterpenes, GA-TP (1), ganodermic acid Jc (GmA-Jc) (2), GmA-Jd (3), GA-TQ1 (4), and ganoderal B1 (5), and fourteen known triterpenes 6–19 were isolated from the ethanol extract. Their structures were identified by mass and extensive NMR spectroscopy. A green chemical HPLC analytical method was developed using ethanol and acetic acid as a mobile phase, and all isolated compounds can be well separated. These triterpenes comprise a unique HPLC chromatograph of the G. lucidum mycelium. All four G. lucidum strains showed the same HPLC chromatographic pattern, whereas G. formosanum displayed a different pattern. Quantitation methods for ganoderic acid T (10) and S (12) were also validated. (4) Conclusions: The triterpenoid HPLC analytical method can be used to identify the G. lucidum species and to determine the contents of GA-T and GA-S.

Foliar diseases caused by Stemphylium and Colletotrichum species are among the major biotic factors limiting Welsh onion production in Taiwan. Owing to concerns about the environment and the development of pathogen resistance to existing fungicides, biological control using endophytes is emerging as an eco-friendly alternative to chemical control. The aim of the present study was to isolate endophytes from healthy Welsh onion leaves and investigate their antagonistic potential against the major phytopathogenic fungi associated with Welsh onion plants in Taiwan. A total of 109 bacterial and 31 fungal strains were isolated from healthy Welsh onion leaves and assigned to 16 bacterial and nine fungal genera using morphological and molecular characterization based on DNA sequence data obtained from nuclear internal transcribed spacer (nrITS) (fungi) and 16S rRNA (bacteria). Evaluation of these endophytic isolates for biocontrol activity against leaf blight pathogens Colletotrichum spaethianum strain SX15-2 and Stemphylium vesicarium strain SX20-2 by dual culture assay and greenhouse experiments resulted in the identification of two bacterial isolates (GFB08 and LFB28) and two fungal isolates (GFF06 and GFF08) as promising antagonists to leaf blight pathogens. Among the four selected isolates, Bacillus strain GFB08 exhibited the highest disease control in the greenhouse study. Therefore, Bacillus strain GFB08 was further evaluated to understand the mechanism underlying its biocontrol efficacy. A phylogenetic analysis based on six genes identified Bacillus strain GFB08 as B. velezensis. The presence of antimicrobial peptide genes (baer, bamC, bmyB, dfnA, fenD, ituC, mlna, and srfAA) and the secretion of several cell wall degrading enzymes (CWDEs), including cellulase and protease, confirmed the antifungal nature of B. velezensis strain GFB08. Leaf blight disease suppression by preventive and curative assays indicated that B. velezensis strain GFB08 has preventive efficacy on C. spaethianum strain SX15-2 and both preventive and curative efficacy on S. vesicarium strain SX20-2. Overall, the current study revealed that healthy Welsh onion leaves harbour diverse bacterial and fungal endophytes, among which the endophytic bacterial strain, B. velezensis strain GFB08, could potentially be used as a biocontrol agent to manage the leaf blight diseases of Welsh onion in Taiwan.

Camellia sinensis is one of the major crops grown in Taiwan and has been widely cultivated around the island. Tea leaves are prone to various fungal infections, and leaf spot is considered one of the major diseases in Taiwan tea fields. As part of a survey on fungal species causing leaf spots on tea leaves in Taiwan, 19 fungal strains morphologically similar to the genus Diaporthe were collected. ITS (internal transcribed spacer), tef1-α (translation elongation factor 1-α), tub2 (beta-tubulin), and cal (calmodulin) gene regions were used to construct phylogenetic trees and determine the evolutionary relationships among the collected strains. In total, six Diaporthe species, including one new species, Diaporthe hsinchuensis, were identified as linked with leaf spot of C. sinensis in Taiwan based on both phenotypic characters and phylogeny. These species were further characterized in terms of their pathogenicity, temperature, and pH requirements under laboratory conditions. Diaporthe tulliensis, D. passiflorae, and D. perseae were isolated from C. sinensis for the first time. Furthermore, pathogenicity tests revealed that, with wound inoculation, only D. hongkongensis was pathogenic on tea leaves. This investigation delivers the first assessment of Diaporthe taxa related to leaf spots on tea in Taiwan.

Objective To analyze the effect and medical self-crosslinking sodium hyaluronate gel on epidural scar adhesion after laminectomy. Methods A total of 24 New Zealand L5 laminectomy rabbits were randomly divided into four groups, group A as the control group without any treatment; group B covered by sodium hyaluronate gel; group C and group D covered by 0.5 and 1.0 mL medical self-crosslinking sodium hyaluronate gel. All rabbits were scored at various time points after 2, 4, 6, 8, 12 weeks, then the formation of scar was observed. Results In Groups B, C, D loose scar tissue occurred after 2 weeks of the operation, scar tissues were significantly less than that in group A, with mild inflammatory reaction. After 8 weeks, the scar tissues of group B were significantly more than that of groups C, D. After two weeks, group B, C were back to the preoperative level; After 4 weeks, group D was back to the preoperative level; After four weeks, the CSEP of group A was increased significantly, which was significantly higher than that in groups B, C, D. The motor function score of group A, group B and group C were the same as preoperative, but that in group D it was decreased significantly, and then it gradually recovered. After 4 weeks it kept a stable level. The motor function score of group A was decreased gradually after the operation, which kept a stable level after 4 weeks, the motor function score was significantly lower than that in groups B, C, D. Conclusions Determination of somatosensory evoked potentials is sensitive indicator of spinal cord injury; Application of medical self-crosslinking sodium hyaluronate gel is effective on epidural scar adhesion after laminectomy. [ABSTRACT FROM AUTHOR]

In this paper, the morphological transition from dendrite to symmetry-broken dendrite is investigated in the directional solidification of non-axially-oriented crystals using a quantitative phase-field model. The effects of pulling velocity and crystal orientation on the morphological transition are investigated. The results indicate the orientation dependence of the symmetry-broken double dendrites. A dendrite to symmetry-broken dendrite transition is found by varying the pulling velocity at different crystal orientations and the symmetry-broken multiple dendrites emerge as a transition state for the symmetry-broken double dendrites. The state region during the transition can be well characterized through the variations of the characteristic angle and the average primary dendritic spacing. [ABSTRACT FROM AUTHOR]

The N2-plasma treatment on a HfO2 blocking layer of Au nanocrystal nonvolatile memory without any post annealing is investigated. The electrical characteristics of the MOS capacitor with structure of Al–TaN/HfO2/SiO2/p-Si are also characterized. After N2-plasma treatment, the nitrogen atoms are incorporated into HfO2 film and may passivate the oxygen vacancy states. The surface roughness of HfO2 film can also be reduced. Those improvements of HfO2 film lead to a smaller hysteresis and lower leakage current density of the MOS capacitor. The N2-plasma is introduced into Au nanocrystal (NC) nonvolatile memory to treat the HfO2 blocking layer. For the N2-plasma treated device, it shows a better retention characteristic and is twice as large in the memory window than that for the no N2-plasma treated device. It can be concluded that the N2-plasma treatment method can be applied to future nonvolatile memory applications. [ABSTRACT FROM AUTHOR]

Polycrystalline Ge1−x (poly-Ge1−xSnx) alloy thin films with high Sn content (> 10%) were fabricated by cosputtering amorphous GeSn (a-GeSn) on Ge (100) wafers and subsequently pulsed laser annealing with laser energy density in the range of 250 mJ/cm2 to 550 mJ/cm2. High quality poly-crystal Ge0.90Sn0.10 and Ge0.82Sn0.18 films with average grain sizes of 94 nm and 54 nm were obtained, respectively. Sn segregation at the grain boundaries makes Sn content in the poly-GeSn alloys slightly less than that in the corresponding primary a-GeSn. The crystalline grain size is reduced with the increase of the laser energy density or higher Sn content in the primary a-GeSn films due to the booming of nucleation numbers. The Raman peak shift of Ge–Ge mode in the poly crystalline GeSn can be attributed to Sn substitution, strain, and disorder. The dependence of Raman peak shift of the Ge–Ge mode caused by strain and disorder in GeSn films on full-width at half-maximum (FWHM) is well quantified by a linear relationship, which provides an effective method to evaluate the quality of poly-Ge1−xSnx by Raman spectra. [ABSTRACT FROM AUTHOR]

High-performance Ge n+/p junctions were fabricated at a low formation temperature from 325 °C to 400 °C with a metal(nickel)-induced dopant activation technique. The obtained NiGe electroded Ge n+/p junction has a rectification ratio of 5.6× 104 and a forward current of 387 A/cm2 at −1 V bias. The Ni-based metal-induced dopant activation technique is expected to meet the requirement of the shallow junction of Ge MOSFET. [ABSTRACT FROM AUTHOR]

A bipolar one-diode–one-resistor (1D1R) device with a Pt/HfO2/Ti/n-Si(001) structure was demonstrated. The 1D1R resistive random access memory (RRAM) device consists of a Ti/n-Si(001) diode and a Pt/HfO2/Ti resistive switching cell. By using the Ti layer as the shared electrode for both the diode and the resistive switching cell, the 1D1R device exhibits the property of stable self-compliance and the characteristic of robust resistive switching with high uniformity. The high/low resistance ratio reaches 103. The electrical RESET/SET curve does not deteriorate after 68 loops. Low-temperature studies show that the 1D1R RRAM device has a critical working temperature of 250 K, and at temperatures below 250 K, the device fails to switch its resistances. [ABSTRACT FROM AUTHOR]