The Impact of Aboveground Epichloë Endophytic Fungi on the Rhizosphere Microbial Functions of the Host Melica transsilvanica.

In nature, the symbiotic relationship between plants and microorganisms is crucial for ecosystem balance and plant growth. This study investigates the impact of Epichloë endophytic fungi, which are exclusively present aboveground, on the rhizosphere microbial functions of the host Melica transsilvanica. Using metagenomic methods, we analyzed the differences in microbial functional groups and functional genes in the rhizosphere soil between symbiotic (EI) and non-symbiotic (EF) plants. The results reveal that the presence of Epichloë altered the community structure of carbon and nitrogen cycling-related microbial populations in the host's rhizosphere, significantly increasing the abundance of the genes (porA, porG, IDH1) involved in the rTCA cycle of the carbon fixation pathway, as well as the abundance of nxrAB genes related to nitrification in the nitrogen-cycling pathway. Furthermore, the presence of Epichloë reduces the enrichment of virulence factors in the host rhizosphere microbiome, while significantly increasing the accumulation of resistance genes against heavy metals such as Zn, Sb, and Pb. This study provides new insights into the interactions among endophytic fungi, host plants, and rhizosphere microorganisms, and offers potential applications for utilizing endophytic fungi resources to improve plant growth and soil health.

High repetition rate correlated photon pair generation in integrated silicon nanowires.

Integrated single-photon sources are a key component for photonic quantum technology but are generally limited to low single-photon rates. For sources based on photon pair generation by four-wave mixing, increasing the repetition rate of pump laser pulses is a straightforward way to enhance the single-photon rate, but the benefits and practical limitations have not yet been demonstrated and analyzed in a CMOS-compatible platform. In this work, we demonstrate correlated photon pair generation in integrated silicon nanowires and systematically analyze the count rate and coincidence to accidental ratio as the pump rate is varied between 156.25 MHz and 10 GHz. We show that the highest useful pump rate is limited by the timing resolution of the single-photon detection system, and that in this regime, the nonlinear loss of the silicon nanowire does not have a significant effect on the single-photon generation.

Frequency conversion in silicon in the single photon regime.

Quantum communication networks require single photon frequency converters, whether to shift photons between wavelength channels, to shift photons to the operating wavelength of a quantum memory, or to shift photons of different wavelengths to be of the same wavelength, to enable a quantum interference. Here, we demonstrate frequency conversion of laser pulses attenuated to the single photon regime in an integrated silicon-on-insulator device using four-wave mixing Bragg scattering, with conversion efficiencies of up to 12%, or 32% after correcting for nonlinear loss created by the pump lasers. The frequency shift can be conveniently chosen by tuning of the pump frequencies. We demonstrate that such frequency conversion enables interference between photons at different frequencies.

Degenerate photon-pair generation in an ultracompact silicon photonic crystal waveguide.

We demonstrate degenerate, correlated photon-pair generation via slow-light-enhanced spontaneous four-wave mixing in a 96 µm long silicon photonic crystal waveguide. Our device represents a more than 50 times smaller footprint than silicon nanowires. We have achieved a coincidence-to-accidental ratio as high as 47 at a photon generation rate of 0.001 pairs per pulse and 14 at a photon generation rate of 0.023 pairs per pulse, which are both higher than the useful level of 10. This demonstration provides a path to generate indistinguishable photons in an ultracompact platform for future quantum photonic technologies.

Chalcogenide fiber-based distributed temperature sensor with sub-centimeter spatial resolution and enhanced accuracy.

We demonstrate a sub-centimeter spatial resolution fiber-based distributed temperature sensor with enhanced measurement accuracy and reduced acquisition time. Our approach employs time domain analysis of backscattered Stokes and anti-Stokes photons generated via spontaneous Raman scattering in a chalcogenide (ChG) As2S3 fiber for temperature monitoring. The sensor performance is significantly improved by exploiting the high Raman coefficient and increased refractive index of the ChG fiber. We achieve a temperature uncertainty of ± 0.65 °C for a short measurement time of only 5 seconds; whilst the detection uncertainty is less than ± 0.2 °C for a longer integration time of 2 minutes. We also investigate the optimum Stokes and anti-Stokes bands for optimal sensing performance. Our theoretical analysis shows that a small detuning frequency regime from a pump is more suitable for rapid measurements while a large detuning regime provides higher temperature resolution.

Low Raman-noise correlated photon-pair generation in a dispersion-engineered chalcogenide As2S3 planar waveguide.

We demonstrate low Raman-noise correlated photon-pair generation in a dispersion-engineered 10 mm As2S3 chalcogenide waveguide at room temperature. We show a coincidence-to-accidental ratio (CAR) of 16.8, a 250 times increase compared with previously published results in a chalcogenide waveguide, with a corresponding brightness of 3×10(5) pairs·s(-1)·nm(-1) generated at the chip. Dispersion engineering of our waveguide enables photon passbands to be placed in the low spontaneous Raman scattering (SpRS) window at 7.4 THz detuning from the pump. This Letter shows the potential for As2S3 chalcogenide to be used for nonlinear quantum photonic devices.

Malignant angiomyolipoma in the liver: a case report with pathological and molecular analysis.

Malignant angiomyolipoma (AML) of the liver is rare. We report a case of AML with malignant transformation and metastases. A 30-year-old man had developed giant hepatic masses. Microscopically, the periphery of the tumor showed components of classic hepatic AML, but the central region contained atypical epithelioid components with extremely pleomorphic and hyperchromatic nuclei with frequent mitotic figures. Immunohistochemical analysis revealed that the epithelioid cells were positive for HMB-45 and smooth muscle actin. Furthermore, the atypical epithelioid cells displayed P53 immunoreactivity and mutation at exon 7 for p53. The tumor showed a typical monoclonal pattern but no loss of heterozygosity or microsatellite instability. Markedly atypical epithelioid cells with vascular invasion, distant metastasis, and fatal outcome were interpreted as malignant characteristics of hepatic AML. It is suggested that large tumor size, pleomorphic nuclei with high proliferation activity, and P53 immunoreactivity may predict the existence of malignant transformation of hepatic AML.

[Experimental study and clinical application of early pedicle division of skin flap by ligation].

OBJECTIVE: To establish a new method of early cut-off skin flap by ligating to stegnosis pedicle and assess its feasibility and clinical application. METHODS: Twenty New Zealand rabbits were used to make skin flaps with the size of 8.0 cm x 4.0 cm on both sides of the back respectively. And one side was experimental group with the pedicles of skin flaps horizontally oversewn by several pairs of silk thread, the other side was control group. Two pairs of silk thread in the two sides of the pedicle of skin flap of experimental group were ligated on the 3rd day. On the 5th day the pedicle was wholly ligated. All pedicles were divided on the 6th day and the survival area of skin flaps were measured after 3 days. The tissue samples from the skin flaps were collected for histology test on the 4th and 6th day respectively. The pedicles of 78 random flaps from 48 patients were cut off after narrowing them by ligating. RESULTS: The mean flap survival rate of the experimental group was statistically higher than the control group. Histological examination results showed the density and diameter of blood vessel were increased in the skin flaps of the experimental group. The mean time for removal pedicles was shortened to 10 days, and no necrosis was found after resecting. CONCLUSIONS: This method is secure and convenient and the time of pedicle division can be shortened.