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Prorocentrum donghaiense is a common but dominant harmful algal bloom (HAB) species, which is widely distributed along the China Sea coast. Development of methods for rapid and precise identification and quantification is prerequisite for early-stage warning and monitoring of blooms due to P. donghaiense. In this study, sequences representing the partial large subunit rDNA (D1-D2), small subunit rDNA and internal transcribed spacer region (ITS-1, 5.8S rDNA and ITS-2) of P. donghaiense were firstly obtained, and then seven candidate DNA probes were designed for performing fluorescence in situ hybridization (FISH) tests on P. donghaiense. Based on the fluorescent intensity of P. donghaiense cells labeled by the DNA probes, the probe DP0443A displayed the best hybridization performance. Therefore, a PNA probe (PP0443A) analogous to DP0443A was used in the further study. The cells labeled with the PNA probe displayed more intensive green fluorescence than that labeled with its DNA analog. The PNA probe was used to hybridize with thirteen microalgae belonging to five families, i.e., Dinophyceae, Prymnesiophyceae, Raphidophyceae, Chlorophyceae and Bacillariophyceae, and showed no visible cross-reaction. Finally, FISH with the probes PP0443A and DP0443A and light microscopy (LM) analysis aiming at enumerating P. donghaiense cells were performed on the field samples. Statistical comparisons of the cell densities (cells/L) of P. donghaiense in the natural samples determined by FISH and LM were performed using one-way ANOVA and Duncan's multiple comparisons of the means. The P. donghaiense cell densities determined by LM and the PNA probe are remarkably higher than (p<0.05) that determined by the DNA probe, while no significant difference is observed between LM and the PNA probe. All results suggest that the PNA probe is more sensitive that its DNA analog, and therefore is promising for the monitoring of harmful algal blooms of P. donghaiense in the future. [ABSTRACT FROM AUTHOR]

Vibrio species are prevalent in ocean ecosystems, particularly Vibrio coralliilyticus, and pose a threat to corals and other marine organisms under global warming conditions. While microbiota manipulation is considered for coral disease management, understanding the role of commensal bacteria in stress resilience remains limited. Here, a single bacterial species (Ruegeria profundi) rather than a consortium of native was used to combat pathogenic V. coralliilyticus and protect corals from bleaching. R. profundi showed therapeutic activity in vivo, preventing a significant reduction in bacterial diversity in bleached corals. Notably, the structure of the bacterial community differed significantly among all the groups. In addition, compared with the bleached corals caused by V. coralliilyticus, the network analysis revealed that complex interactions and positive correlations in the bacterial community of the R. profundi protected non-bleached corals, indicating R. profundi's role in fostering synergistic associations. Many genera of bacteria significantly increased in abundance during V. coralliilyticus infection, including Vibrio, Alteromonas, Amphritea, and Nautella, contributing to the pathogenicity of the bacterial community. However, R. profundi effectively countered the proliferation of these genera, promoting potential probiotic Endozoicomonas and other taxa, while reducing the abundance of betaine lipids and the type VI section system of the bacterial community. These changes ultimately influenced the interactive relationships among symbionts and demonstrated that probiotic R. profundi intervention can modulate coral-associated bacterial community, alleviate pathogenic-induced dysbiosis, and preserve coral health. These findings elucidated the relationship between the behavior of the coral-associated bacterial community and the occurrence of pathological coral bleaching. IMPORTANCE Changes in the global climate and marine environment can influence coral host and pathogen repartition which refers to an increased likelihood of pathogen infection in hosts. The risk of Vibrio coralliilyticus-induced coral disease is significantly heightened, primarily due to its thermos-dependent expression of virulent and populations. This study investigates how coral-associated bacterial communities respond to bleaching induced by V. coralliilyticus. Our findings demonstrate that Ruegeria profundi exhibits clear evidence of defense against pathogenic bacterial infection, contributing to the maintenance of host health and symbiont homeostasis. This observation suggests that bacterial pathogens could cause dysbiosis in coral holobionts. Probiotic bacteria display an essential capability in restructuring and manipulating coral-associated bacterial communities. This restructuring effectively reduces bacterial community virulence and enhances the pathogenic resistance of holobionts. The study provides valuable insights into the correlation between the health status of corals and how coral-associated bacterial communities may respond to both pathogens and probiotics. [ABSTRACT FROM AUTHOR]

Carbon was successfully introduced into NdMnxCr2−xSi2 serial compounds as an interstitial atom. The compounds with x  ⩽  0.5 keep a CeMg2Si2-type structure while the structure changes slowly with increasing manganese content. Finally, a new superstructure was found and determined for x around 1.7. All the compounds for x  =  1.1, 1.3, 1.5 and 1.7 have two magnetic phase transition temperatures around 43 and 314 K. What is more, a giant magnetocaloric effect has been observed around the lower phase transition temperature, TR ~ 51 K, in NdMn1.7Cr0.3Si2C. The maximum values of the magnetic entropy change  −ΔSM for the field change of 2 T and 5 T are 14.9 J kg−1 K−1 and 26.0 J kg−1 K−1, which means the interstitial atom effect enhanced the MCE values for 85% and 63% compared to NdMn1.7Cr0.3Si2, respectively. NdMn1.7Cr0.3Si2C with first order magnetic transition but low hysteresis losses (thermal  <  ~0.58 K; magnetic field  <  ~0.12 T) can be a candidate for magnetic refrigerator applications in the temperature region near 50 K. Besides, two field-induced magnetic phase transitions were found in NdMn1.7Cr0.3Si2C among the temperature range from 53 to 60 K, and a linear relation between the phase transition field and temperature was found and analyzed. [ABSTRACT FROM AUTHOR]

The crystal structure and magnetic properties of AlFe2−xMnxB2 (x = 0–0.5) compounds were investigated. With increasing Mn content, the magnetic properties of these compounds evolve gradually and the lattice parameters change continuously: Curie temperature (Tc) decreases from 312 K (x = 0) to 220 K (x = 0.5) and a new phase transition from the ferromagnetic state (FM) to spin-glass state (SPG) appears upon cooling. The lattice shrinks in the ab plane while it expands in the c direction. The formation of re-entrant SPG around 50 K was studied via temperature dependent ac and dc magnetization as well as the initial magnetization curves in 5 K. The reason for this glass state is the triangular configuration of magnetic atoms and the antiferromagnetic interactions introduced by Mn substitutions. The Curie transition leads to a conventional magnetocaloric effect (MCE). The Mn doping leads to a decrease in the MCE near room temperature, but there is a plane in entropy change (ΔS) for the x = 0.1 compound under low field which makes these compounds good candidates to produce composites used for magnetic refrigeration application in a wide temperature span. [ABSTRACT FROM AUTHOR]

Aim of the study: To investigate the effects of P27RF-Rho on hepatocellular carcinoma (HCC) cell growth and explore the possibility of using it as a novel therapeutic target for liver cancer treatment. Material and methods: P27RF-Rho in HCC cells was silenced by lentivirus- mediated RNA interference, and the silencing effect was verified by RTPCR. Cell proliferation was determined by MTT and clone formation assay. Cell cycle phase and apoptosis were detected through FACS. The expression level of cell growth, apoptosis, and metastasis associated genes was detected by quantitative PCR. Results: Lentivirus-mediated P27RFRho knockdown inhibited HCC cell growth and clone formation. P27RFRho silence induced cell cycle arrest and apoptosis. The mRNA level of genes associated with cell cycle, apoptosis, and invasion also significantly altered after P27RF-Rho knockdown. Cyclin A, CDK2, BCL-2, and MMP-9 were down-regulated. P27 and Bax were up-regulated. Conclusions: P27RF-Rho knockdown inhibits HCC cell growth, and P27RFRho is probably a promising target for HCC treatment. [ABSTRACT FROM AUTHOR]

We design a low-timing-jitter, repetition-rate-tunable, stretched-pulse passively mode-locked fiber laser by using a nonlinear amplifying loop mirror (NALM), a semiconductor saturable absorber mirror (SESAM), and a tunable optical delay line in the laser configuration. Low-timing-jitter optical pulses are stably produced when a SESAM and a 0.16 m dispersion compensation fiber are employed in the laser cavity. By inserting a tunable optical delay line between NALM and SESAM, the variable repetition-rate operation of a self-starting, passively mode-locked fiber laser is successfully demonstrated over a range from 49.65 to 50.47 MHz. The experimental results show that the newly designed fiber laser can maintain the mode locking at the pumping power of 160 mW to stably generate periodic optical pulses with width less than 170 fs and timing jitter lower than 75 fs in the 1.55 µm wavelength region, when the fundamental repetition rate of the laser is continuously tuned between 49.65 and 50.47 MHz. Moreover, this fiber laser has a feature of turn-key operation with high repeatability of its fundamental repetition rate in practice. [ABSTRACT FROM AUTHOR]

Deals with a study which explained theoretically the multi-peak spectrum of Ti:sapphire pulses observed experimentally under ultrabroad bandwidth conditions. Description of the experimental setup and multi-peak spectrum; Discussion on the self-phase modulation and four-wave frequency-mixing; Conclusion.

Ras homologous C (RhoC) is expressed in various cancers, including hepatocellular carcinoma (HCC). In this study, we first analyzed RhoC expression in 46 HCC tissue specimens and found that RhoC expression was significantly increased in HCC tissues compared to the adjacent normal liver tissues. Next, we investigated the role of RhoC in malignant transformation of normal hepatocytes. The HL7702 cell line was stably transfected with a RhoC expression vector and then subjected to cell proliferation, differentiation, colony formation, migration and invasion assays, as well as nude mouse xenograft assays. Gene expressions in these cells were determined using RT-PCR and Western blot. Overexpression of RhoC significantly promoted proliferation and anchorage-independent growth of HL7702 cells, but suppressed cell differentiation, as compared with the parental cells and the empty vector-transfected control cells. Moreover, RhoC overexpression induced migration and invasion of HL7702 cells in vitro. Molecularly, RhoC increased the expression of cell cycle-related genes, matrix metalloprotease 2 (MMP2), MMP9 and vascular endothelial growth factor (VEGF). In addition, RhoC-transfected cells formed tumors in nude mice, whereas vector-transfected HL7702 cells did not form any tumors in nude mice. This study demonstrated the role of RhoC overexpression in malignant transformation of normal human hepatocytes, suggesting that RhoC may function as an oncogene in hepatocytes. [ABSTRACT FROM AUTHOR]

Abstract: We report on the experimental demonstration of a spectrum shaping filter, which is formed by inserting a fiber polarization controller (PC) in to a Sagnac loop. Pedestal free and narrow spectrum with line width at 1.4–1.7nm is obtained, which is advantageous for further power amplification and effective frequency doubling. [Copyright &y& Elsevier]

With the assistance of a kind of photonic Robin Hood that is originated from four-wave mixing in a dispersion-flattened high-nonlinearity photonic-crystal fibre, a novel dual-wavelength erbium-doped fibre (EDF) laser is proposed and demonstrated by using a sampled fibre Bragg grating. The experiments show that, due to the contribution of the photonic Robin Hood, the proposed fibre laser has the advantage of excellent uniformity, high stability and stable operation at room temperature. Our dual-wavelength EDF laser has the unique merit that the wavelength spacing remains unchanged when tuning the two wavelengths of laser, and this laser is simpler and more stable than the laser reported by Liu et al. [Opt. Express, 13 142 (2005)]. [ABSTRACT FROM AUTHOR]

The optical properties and potential applications of four kinds of fulgide and fulgimide were studied. A parallel optical storage apparatus was set up, which could reach the area density of 4.8 × 10 7 bits/cm 2 on the fulgide/PMMA film. Fourier transform orthogonal circular polarization holographic data storage was performed with high signal-to-noise-ratio reconstruction image, which obtained the storage density of 2 × 10 8 bits/cm 2 for single hologram. Two-photon induced micro-patterns were recorded on the fulgimide/PMMA film with 800 nm, 100 fs, 1 KHz, 50 mW femtosecond laser. Dual-wavelength (650 nm and 488 nm) optical images storage were tested on a two-color mixing fulgides/PMMA film. [ABSTRACT FROM AUTHOR]