Tin diselenide (SnSe2) nanosheets as novel 2D layered materials have excellent optical properties with many promising application prospects, such as photoelectric detectors, nonlinear optics, ...infrared photoelectric devices, and ultrafast photonics. Among them, ultrafast photonics has attracted much attention due to its enormous advantages; for instance, extremely fast pulse, strong peak power, and narrow bandwidth. In this work, SnSe2 nanosheets are fabricated by using solvothermal treatment, and the characteristics of SnSe2 are systemically investigated. In addition, the solution of SnSe2 nanosheets is successfully prepared as a fiber‐based saturable absorber by utilizing the evanescent field effect, which can bear a high pump power. 31st‐order subpicosecond harmonic mode locking is generated in an Er‐doped fiber laser, corresponding to the maximum repetition rate of 257.3 MHz and pulse duration of 887 fs. The results show that SnSe2 can be used as an excellent nonlinear photonic device in many fields, such as frequency comb, lasers, photodetectors, etc.
Tin diselenide (SnSe2) nanosheets as novel 2D layered materials have excellent optical properties. SnSe2 nanosheets fabricated by using solvothermal treatment are successfully prepared as fiber‐based saturable absorbers by utilizing the evanescent field effect, which can bear a high pump power. 31st‐order subpicosecond harmonic mode‐locking is generated, corresponding to 257.3 MHz repetition rate.
The protozoan Cryptocaryon irritans is one of the most important ectoparasites of marine fish, causing ‘white spot disease’ and mass mortality in aquaculture. To accurately predict disease outbreaks ...and develop prevention strategies, improved detection methods are required that are sensitive, convenient and rapid. In this study, a pair of specific primers based on the C. irritans 18S rRNA gene was developed and used in a real‐time PCR (qPCR) assay. This assay was able to detect five theronts in 1 L of natural seawater. Furthermore, a linear model was established to analyse the log of Ct value and parasite abundance in seawater (y = –2.9623x + 24.2930), and the coefficient of determination (R2) value was 0.979. A lysis buffer was optimized for theront DNA extraction and used for storage sample. This method was superior to the commercial water DNA kit, and there was no significant degradation of DNA at room temperature for 24–96 hr. A dilution method was developed to manage qPCR inhibitors and used to investigate natural seawater samples in a net cage farm with diseased fish, and the findings were consistent with the actual situation. This study provides a valuable tool for assisting in the early monitoring and control of cryptocaryoniasis in aquaculture.
Peroxisome proliferator‐activated receptor gamma coactivator 1‐alpha (PPARGC1A) is a central regulator of mitochondrial biogenesis and metabolism, and its expression is closely related to embryo ...development. To gain insights into the possible mechanisms of PPARGC1A during early embryogenesis, the development potential, mitochondrial biogenesis, and the culture medium metabolomics of embryos were evaluated when PPARGC1A overexpressed or suppressed in rabbit zygotes. Results showed that different PPARGC1A levels in rabbit zygotes could affect blastocyst percentage, and the expressions of mitochondrial biogenesis and metabolic‐related genes, as well as the glutathione and adenosine triphosphate levels during early embryo development. In addition, compared with the controls, 12 and 10 different metabolites involved in carbohydrate, amino acid, and fatty acid metabolism were screened in the 5 day's spent culture medium of PPARGC1A overexpressed and suppressed embryos by gas chromatography–mass spectrometer, respectively. Consistent with these metabolite changes, the transcriptions of genes encoding glucose transporters and fatty acid biosynthetic proteins in the embryos from different groups were regulated by PPARGC1A during rabbit embryo development. Taken together, these data provide evidence that PPARGC1A may regulate early rabbit embryo development through mitochondrial biogenesis and metabolism.
Proliferator‐activated receptor gamma coactivator 1‐alpha (PPARGC1A) improved rabbit embryo development; increased mitochondrial biogenesis in PPARGC1A overexpressed embryos; PPARGC1A overexpressed embryos exhibited high glucose consumption and glutamine uptake.
In this study, we utilized nano-sized Co3O4 and reduced graphene oxides (rGOs) as composite anode materials for Li-ion batteries. The Co3O4/C composite anode was derived from ZIF67 (Zeolitic ...Imidazolate Framework-67) and was wrapped in rGOs through precipitation. X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) were used to identify the crystal structure, phase purity, and surface morphology of the composite. The composition-optimized Co3O4/rGO/C composite anode exhibited a reversible capacity of 1326 mAh/g in the first cycle, which was higher than that of the Co3O4/C composite anode with a capacity of 900 mAh/g at a current density of 200 mA/g. Moreover, after 80 cycles, Co3O4/rGO/C maintained a capacity of 1251 mAh/g at the same current density, which was also higher than the bare Co3O4/C composite (595 mAh/g). Additionally, the Co3O4/rGO/C composite exhibited a good capacity retention of 98% after 90 cycles, indicating its excellent cycling stability and high capacity. Therefore, the Co3O4/rGO/C electrode has great potential as a promising anode material for Li-ion batteries.
The spatial distribution of the preferential flow path in soil affects the occurrence and movement of preferential flow. In afield soil staining and tracing experiment, with the help of morphological ...image analysis technology and community ecological analysis method, we examined the spatial distribution characteristics of preferential flow path in paddy fields under straw mulching (CM) and non-mulching (CK) in karst areas of Guangxi. The results showed that, under the same external water supply conditions, with the increases of soil depth, soil horizontal dyeing changed from overall distribution to clump aggregation distribution in paddy field under straw mulching. In the non-mulching paddy field, the main dyeing was branch, with an average shape coefficient of staining patch of 21.69. The dyeing morphology in the non-mulching paddy field was 1.04 times of straw mulching paddy field. The preferential flow paths of straw mulching and non-mulching paddy fields showed both clustered distribution. In straw mulchi
Fe3O4 nanoparticles (FONPs) are magnetic materials with a small band gap and have well-demonstrated applications in ultrafast photonics, medical science, magnetic detection, and electronics. Very ...recently, FONPs were proposed as an ideal candidate for pulse generation in fiber-based oscillators. However, the pulses obtained to date are on the order of microseconds, which is too long for real application in communication. Here, we report the use of FONPs synthesized by a sol–hydrothermal method and used as a saturable absorber (SA) to achieve nanosecond pulses in an erbium-doped fiber laser (EDFL) for the first time. The proposed fiber laser is demonstrated to have a narrow spectral width of around 0.8 nm and a fixed fundamental repetition rate (RPR) of 4.63 MHz, whose spectra and pulse dynamics are different from the mode-locked lasers reported previously. It is demonstrated that the proposed fiber laser based on a FONP SA operates in the giant-chirp mode-locked regime. The most important result is the demonstration of a pulse duration of 55 ns at an output power of 16.2 mW, which is the shortest pulse based on FONPs for EDFLs reported to date. Our results demonstrate that the FONP dispersion allows for an excellent photonic material for application in ultrafast photonics devices, photoconductive detectors, and optical modulators.
The emergence and prevalence of antibiotic-resistant bacteria demands powerful antibacterial tactics to combat infectious microorganisms. Enhanced combinational therapy based on synergistic hybrid ...antibacterial materials is a promising approach to realize effective sterilization through the rational integration of distinct bactericides into one compact platform. In this work, we constructed a microfiber-based antibacterial platform (PAM-Cl/ZnO MFs) by electrospinning N-halamine polymers (PAM-Cl) loaded with zinc oxide (ZnO) nanoparticles. The as-designed PAM-Cl/ZnO MFs inherited the intrinsic antibacterial effects of both PAM-Cl microfibers (PAM-Cl MFs) and ZnO microfibers (ZnO MFs), and the material exhibited enhanced synergistic antibacterial performance against
Staphylococcus aureus
(
S. aureus
) and
Escherichia coli
(
E. coli
) in vitro. The bactericidal effect was multimodal and included contact killing based on the N–Cl bond of N-halamine, multiple-release killing, such as reactive oxygen species (ROS) under light irritation, and Zn
2+
and Cl
+
acting as antibacterial agents. Importantly, PAM-Cl/ZnO MFs worked on inactivate bacteria even under harsh temperatures and atmospheric conditions. Additionally, PAM-Cl/ZnO MFs exhibited good biocompatibility and performed outstanding acceleration of wound healing with in vivo mouse skin defect models using
S. aureus
. This work advances the design of antibacterial hybrid materials with the potency to eradicate bacteria in biological systems in multiple settings through the superiority of multimodal synergistic therapy.
Graphical abstract
Marine cultured fish in tropical and sub-tropical regions often suffer from white spot disease, caused by Cryptocaryon irritans infection. This can lead to mass mortality and economic loss. This ...study investigated the use of seawater-adapted red tilapias (Oreochromis niloticus × O. mossambicus) as scavengers for cleaning tomonts, to protect susceptible marine fish from C. irritans infection. The sensitivity of red tilapia to C. irritans infection, the effectiveness of red tilapia in consuming tomonts, and the efficacy for protecting the vulnerable Trachinotus ovatus from C. irritans infection were evaluated. The results showed that the susceptibility of red tilapia to C. irritans infection was significantly lower than T. ovatus and the rate of tomonts consumption by red tilapia was positively correlated with the number of tomonts in the seawater. The relative percent survival of T. ovatus infected with C. irritans and co-cultured with red tilapias (at a density of 19 red tilapias/m2) was 97.78% at the12 days post-infection. This study indicates that polyculture with red tilapia could be a potential alternative biocontrol strategy to eliminate tomonts, for controlling C. irritans reinfection.
•Red tilapia show low sensitivity to Cryptocaryon irritans infection.•Red tilapia can clean Cryptocaryon irritans tomonts effectively.•Polyculture with red tilapia could protect against reinfection.
Cryptocaryoniasis is a severe disease of marine cage culture fish, caused by the protozoan Cryptocaryon irritans. However, the sources of C. irritans infection in cage culture farms are still ...unclear. Previous studies confirmed many cases of biological fouling on the nets of the culture cages. Therefore, we speculate that fouling may be a key infection source of the cryptocaryoniosis outbreaks. This study evaluated whether tomonts develop the dormant stage at different seawater depths and in the sludge. The results showed that the seabed and sludge tomonts exhibited low division rates on the first 3 days after entering the reproductive stage. However, no significant differences in the hatching rate of seabed and sludge tomonts were observed in comparison to the shallow water layer on the 6th day after entering the reproductive stage. The nets with different biological fouling biomass were placed at the base of a tank containing diseased fish. We established that the tomonts could adhere to the net clothing and that the adhesion rate positively correlated with the fouling biomass. In addition, we determined the number of theronts in the seawater at the base of the net cages containing diseased fish in a cage culture farm by a qPCR to detect the DNA of theronts. The number of theronts in the seawater near the bottom of cages with diseased fish was significantly higher than that in other areas. In general, net biofouling is a vital source of C. irritans infection in cage cultures. Our findings provide a theoretical basis for the prevention and control cryptocaryoniasis in the cage culture farms.
•C. irritans tomonts do not accumulate efficiently on the flooring of the cage culture farms.•Tomonts can adhere to the net clothing, with the adhesion rate directly correlating with net fouling biomass.•The number of theronts near the cage bottom with diseased fish is significantly higher than other areas.
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