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Fermented soybean products are widely consumed worldwide, and their popularity is increasing. Filamentous fungi, such as Actinomucor, Aspergillus, Monascus, Mucor, Penicillium, Rhizopus, and Zymomonas, play critical roles in the fermentation processes of many soybean foods. However, besides producing essential enzymes for food fermentation, filamentous fungi can release undesirable or even toxic metabolites into the food. Mycotoxins are toxic secondary metabolites produced by certain filamentous fungi and may be detected during the food production process. Without effective prevention strategies, mycotoxin contamination in fermented soybean products poses a risk to human health. This review focused on the changes in mycotoxigenic fungal abundance and mycotoxin contamination at different stages during the production of soybean-based fermented foods, as well as effective strategies for preventing mycotoxin contamination in such products. Data from relevant studies demonstrated a tendency of change in the genera of mycotoxigenic fungi and types of mycotoxins (aflatoxins, alternariol, alternariol monomethyl ether, deoxynivalenol, fumonisins, ochratoxin A, rhizoxins, T-2 toxin, and zearalenone) present in the raw materials and the middle and final products. The applicability of traditional chemical and physical mitigation strategies and novel eco-friendly biocontrol approaches to prevent mycotoxin contamination in soybean-based fermented foods were discussed. The present review highlights the risks of mycotoxin contamination during the production of fermented soybean products and recommends promising strategies for eliminating mycotoxin contamination risk in soybean-based fermented foods.

Aflatoxins are strong carcinogenic and mutagenic fungal metabolites, and aflatoxin contamination is a critical issue in agriculture and food production. Natural flavonoids can suppress aflatoxin biosynthesis; however, the structure-activity relationship remains unclear. In the present study, a total of 36 structurally related natural flavonoids were tested against the aflatoxigenic Aspergillus flavus, both in-vitro and in-situ (on maize kernels), to investigate their structure-activity relationship and biological activity. Aflatoxin production (IC

The direct in situ synthesis of cadmium sulfide (CdS) nanowires (NWs) was presented by direct synthesis of CdS NWs on the gold surface of an interdigitated electrode (IDE). In this work, we investigated the effect of a strong oxidant on the surfaces of the CdS NWs using X-ray photoelectron spectroscopy, transmission electron microscopy, and time-of-flight secondary ion mass spectrometry. We also fabricated a parylene-C film as a surface passivation layer for in situ-synthesized CdS NW photosensors and investigated the influence of the parylene-C passivation layer on the photoresponse during the coating of parylene-C under vacuum using a quartz crystal microbalance and a photoanalyzer. Finally, we used the in situ-synthesized CdS NW photosensor with the parylene-C passivation layer to detect the chemiluminescence of horseradish peroxidase and luminol and applied it to medical detection of carcinoembryonic antigen.

A new method that uses plasma energy for the deposition of parylene-C films is presented. The equipment and instrumentation for the plasma deposition of parylene-C films were developed and constructed by combining evaporation and plasma-generating units. The plasma deposition of parylene-C films consists of three steps: evaporation, decomposition of the parylene-C dimers using plasma, and deposition of the film. The entire deposition process from evaporation to deposition was designed to be completed within 20 min for a parylene-C film with a thickness of less than 200 nm. The thickness of the parylene-C film was controlled in the range of 100–200 nm by adjusting the amount of parylene-C dimer as well as the plasma energy. The parylene-C films prepared by plasma deposition were characterized and compared with those obtained using the conventional pyrolysis method. The comparison included the chemical properties (chemical functional groups, atomic compositions) and their physical properties (density, crystallinity, absorption in the visible wavelength range, surface roughness and contact angle).

The reproducibility of photosensitivity was analysed for in-situ synthesised CdS nanowire (NW) photosensors according to the distance from the CdS target as well as the position of interdigitated electrodes (IDEs) in the vacuum chamber when the IDEs were the same distance from the target. The influence of Parylene C film as a passivation layer was analysed by changing the gas conditions. Finally, the in-situ synthesised CdS NW photosensor was applied to the detection of chemiluminescence of luminol and to medical diagnostic testing for the human hepatitis B virus antibody.

We studied optical properties and photocurrent characteristics of PbS nanowires grown by chemical vapor deposition. Distinct bandedge photoluminescence (PL) emission was observed in the mid-infrared spectral range and the quantum confinement effect estimated from the PL peak energy was within 40 meV, consistent with the average diameter of the nanowire (∼70 nm) being significantly larger than the exciton Bohr radius (∼18 nm). We also demonstrated interdigit photo detectors making use of these PbS nanowires suspended between two pre-patterned Ti electrodes, where Ti also acted as metal catalyst for the nanowire growth. The threshold wavelength of the photocurrent was found to be ∼3 μm at room temperature.

We report on an Er-doped fiber pulse laser at large net normal dispersion cavity by employing a dispersion compensating fiber in combination with a single-walled carbon nanotube (SWCNT) saturable absorber. A SWCNT/polymer composite film uniformly spin-coated on the side-polished fiber is prepared for robust and efficient nonlinear interaction with evanescent fields in the waveguide expecting increase of optical and thermal damage threshold compared to previously reported direct coating of SWCNTs on fiber ferrules. The fabricated dissipative soliton fiber laser exhibits high average output power of 55.6 mW, corresponding to pulse energy about 2.35 nJ. Highly chirped 5.8 ps pulses are generated with a spectral bandwidth of 13.9 nm and compressed down to 226 fs using additional length of conventional optical fiber at extra-cavity.

Passive harmonic mode-locking in soliton fiber laser is presented with excellent noise characteristics by employing a single-walled carbon nanotubes saturable absorber designed to interact with evanescent wave of the laser field. The 34(th) harmonic mode-locking pulses at 943.16 MHz repetition rate were stably generated with 18 mW output power,50 dB side-mode suppression and -140 dB/Hz relative intensity noise. Soliton energy control with polarization controller further increased the harmonic order to 61st, 1.692 GHz, but with compromised performance. Scaling to higher-order harmonic mode-locking is discussed for practical application in optical communication system.

We demonstrated harmonically mode-locked soliton laser based on evanescent field interaction of carbon-nanotube saturable absorbers. The repetition rate was 943 MHz at 34th harmonics with super-mode suppression of 60 dB at 18 mW output power.