Toward a Comprehensive Understanding of the Anomalously Small Contact Angle of Surface Nanobubbles.

Experimental studies have demonstrated that the gas phase contact angle (CA) of a surface nanobubble (SNB) is much smaller than that of a macroscopic gas bubble. This reduced CA plays a crucial role in prolonging the lifetime of SNBs by lowering the bubble pressure and preventing gas molecules from dissolving in the surrounding liquids. Despite extensive efforts to explain the anomalously small CA, a consensus about the underlying reasons is yet to be reached. In this study, we conducted experimental investigations to explore the influence of gas molecules adsorbed at the solid-liquid interface on the CA of SNBs created through the solvent exchange (SE) method and temperature difference (TD). Interestingly, no significant change is observed in the CA of SNBs on highly oriented pyrolytic graphite (HOPG) surfaces. Even for nanobubbles on micro/nano pancakes, the CA only exhibited a slight reduction compared to SNBs on bare HOPG surfaces. These findings suggest that gas adsorption at the immersed solid surface may not be the primary factor contributing to the small CA of the SNBs. Furthermore, the CA of SNBs formed on polystyrene (PS) and octadecyltrichlorosilane (OTS) substrates was also investigated, and a considerable increase in CA was observed. In addition, the effects of other factors including impurity, electric double layer (EDL) line tension, and pinning force upon the CA of SNBs were discussed, and a comprehensive model about multiple factors affecting the CA of SNBs was proposed, which is helpful for understanding the abnormally small CA and the stability of SNBs.

Green synthesis of silver nanoparticles from Mahonia fortunei extracts and characterization of its inhibitory effect on Chinese cabbage soft rot pathogen.

The pathogenic bacterium Pectobacterium carotovorum causes soft rot in cabbage and significantly reduces plant yield. In this study, we employed Mhonia fortunei extracts to synthesis silver nanoparticles (Mf-AgNPs) and investigated their functions against P. carotovorum. The results showed that the surface plasmon resonance (SPR) peak of AgNP was 412 nm under optimal synthesis conditions. Furthermore, the results of Scanning electron microscope-Energy dispersive spectrometer (SEM-EDS) and High-resolution transmission electron microscopy (HR-TEM) revealed that the Mf-AgNPs had a spherical structure with an average diameter of 13.19 nm and the content of Ag0 ions accounted for 82.68% of the total elemental content. The X-Ray diffraction (XRD) results confirmed that AgNPs had a face-centered cubic (FCC) crystal structure, while Fourier transform infrared spectroscopy (FTIR) results indicated the presence of various biomolecules as reducing and stabilizing agents on the AgNP surface. Antibacterial activity was first evaluated by an inhibitory zone test, which revealed that 500 µg ml-1 of AgNPs had antibacterial activity against P. carotovorum and four model bacteria including Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and Pseudomonas aeruginosa, respectively with an antibacterial function comparable to 1 mM AgNO3 solution. The Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values for P. carotovorum were 8 µg ml-1, respectively. Furthermore, AgNPs at 8 µg ml-1 completely inhibited the growth of P. carotovorum, decreased their tolerance to 0.25 mM H2O2 as well as considerably reduced colony formation after 1 h of treatment and thereafter. Treatment with Mf-AgNPs resulted in bacterial cell membrane destruction and biofilm formation inhibition, respectively. With an FIC (fractional inhibitory concentration) index of 0.174, AgNP and zhongshengmycin showed a significant synergistic effect. The infection of P. carotovorum to cabbage explants was significantly inhibited in vitro by a combination of 2 µg ml-1 Mf-AgNP and 5 µg ml-1 zhongshengmycin. In conclusion, the synthesized Mf-AgNP exhibited significant antibacterial activity against P. carotovorum.

Alleviative effects of nitric oxide on Vigna radiata seedlings under acidic rain stress.

Although nitric oxide (NO) is a key regulatory molecule in plants, its function in plants under conditions of simulated acid rain (SAR) has not been fully established yet. In this study, exogenous sodium nitroprusside (SNP) at three different concentrations were applied to mung bean seedlings. Malondialdehyde (MDA), NO, hydrogen peroxide (H2O2), antioxidant enzyme activities, and nitrate reductases (NR) were measured. Real time PCR was used to measure the NR expression. Compared to the control, the NR activity and NO content under the pH 2 SAR decreased by 79% and 85.6% respectively. Meanwhile, the SAR treatment reduced the activities of superoxide dismutase (SOD), peroxidase (POD), ascorbate peroxidase (APX), while increased MDA content. Application of SNP could potentially reverse the adverse impact of SAR, depending on its concentration. For plants under the pH 2 SAR and 0.25 mM SNP condition, the activities of SOD, POD, APX increased by 123%, 291%, and 135.7% respectively, meanwhile, MDA concentration decreased by 43%, NR activities increased by 269%, and NO concentration increased by 123.6% compared with plants undergoing only pH 2 SAR. The relative expression of the NR1 gene was 2.69 times higher than that of pH 2 SAR alone. Overall, the application of 0.25 mM SNP eliminated reactive oxygen species (ROS) by stimulating antioxidant enzyme activities, reducing oxidative stress and mitigating the toxic effects of SAR on mung bean seedlings. This research provides a foundation for further research on the mechanism of NO on plants under SAR conditions.

Risk prediction and risk factor analysis of urban logistics to public security based on PSO-GRNN algorithm.

For the complicated operation process, many risk factors, and long cycle of urban logistics, it is difficult to manage the security of urban logistics and it enhances the risk. Therefore, to study a set of effective management mode for the safe operation of urban logistics and improve the risk prediction mechanism, is the primary research item of urban logistics security management. This paper summarizes the risk factors to public security in the process of urban logistics, including pick up, warehouse storage, transport, and the end distribution. Generalized regression neural network (GRNN) is combined with particle swarm optimization (PSO) to predict accidents, and the Apriori algorithm is used to analyze the combination of high-frequency risk factors. The results show that the method of combining GRNN with PSO is effective in accident prediction and has a powerful generalization ability. It can prevent the occurrence of unnecessary urban logistics public accidents, improve the ability of relevant departments to deal with emergency incidents, and minimize the impact of urban logistics accidents on social and public security.

Long non-coding RNA UCA1 upregulates KIF20A expression to promote cell proliferation and invasion via sponging miR-204 in cervical cancer.

Cervical cancer is a female cancer with the second highest motility over the world. It is urgent to find new therapeutic methods based on long-coding RNAs and microRNAs. UCA1 was proved to be related with many human cancer types, but limited researches have been performed for the inner associations between UCA1 and cervical cancer. Eighty females who were undergoing surgeries were recruited for study in our research. We took the cervical cancer tissues and cells from them. Massive experiments and analysis were conducted to investigate the gene expressions and protein expressions about UCA1, KIF20A, and miR-204 in normal cells and cancer cells. The techniques contain real-time PCR, migration/invasion assay, western blot, in vivo experiments, and so on.We found that UCA1 expression was greatly up-regulated in cervical cancer tissues and cell lines. Our in vitro assays revealed that the suppressing of UCA1 could reduce cervical cancer cells proliferation, migration, and invasion. In addition, we found that lncRNA UCA1 could sponge miR-204 and promote the proliferation and invasion of cervical cancer cells via the up-regulating of KIF20A expression. As a result, the inhibiting of UCA1 could lower cervical cancer (CC) cells growth rate in vivo.Our results identified that UCA1 could serve as an oncogene in cervical cancer cell progression through the modulating of miR-204/KIF20A axis. It gives novel insights to the searching of novel therapeutic methods for cervical cancer.

De novo transcriptomic analysis of gonad of Strongylocentrotus nudus and gene discovery for biosynthesis of polyunsaturated fatty acids.

BACKGROUND: Strongylocentrotus nudus is an important cultured sea urchin species in north China, because its gonad is rich in unsaturated fatty acids, particularly long polyunsaturated fatty acids (LC-PUFAs). These PUFAs play pleiotropic and crucial roles in a wide range of biological process. OBJECTIVE: However, the genes contributing to biosynthesis PUFAs have not been elucidated yet, and the molecular mechanism relative to the difference in PUFA composition between male and female gonad as been revealed but the corresponding has not been understood. METHODS: In this paper, solexa sequencing based transcriptomic approach was used to identify and characterize the key genes relative to PUFA synthesis and further conducted different expressed genes between male and female gonad. RESULTS: A total of 130,124 transcripts and 189330 unigenes were de novo assembled from 64.32 Gb data. Next, these unigenes were subjected to functional annotation by mapping to six public databases, and this process revealed a lot of genes involving in lipid metabolism. In addition, three types of fatty acids front-end desaturase and three species of very long fatty acids elongase were identified and the pathway for PUFA biosynthesis was hypothesized. Last, comparative analysis revealed the higher expression level of Δ5 desaturase, Δ6 desaturase, ELOVL-4, -6 and -7 in male gonad compared with female. CONCLUSION: This results could plausible explain the differ in composition of PUFAs between male and female gonad of sea urchin.

A hybrid approach based on the analytic hierarchy process and 2-tuple hybrid ordered weighted averaging for location selection of distribution centers.

Distribution centers (DCs) are an important part of the modern logistics system. The selection of a location for a DC is significant for saving costs and reducing externalities caused by distribution. In this paper, we propose a new hybrid method based on the analytic hierarchy process (AHP) and 2-tuple hybrid ordered weighted averaging (THOWA) to select the location of a DC in a megacity. First, we propose a new set of evaluation criteria integrating economic, political, social and ecological information based on the characteristics of Chinese megacities. Second, subjective criteria weights are calculated by AHP combining the evaluation of logistics experts. Third, experts from academia, enterprise and government assess the performance of alternatives. In addition, the overall evaluation values are aggregated by an improved THOWA operator to rank the alternatives. Finally, we conduct a sensitivity analysis to investigate the influence of criteria weights on the decision-making process. The proposed method is novel and addresses the uncertainty under limited quantitative information, which has the advantages of avoiding information loss and distortion problems in the integrating process and operating linguistic evaluation information effectively. The proposed method can be practically applied by municipal planning departments in deciding on the location of new DCs. A numerical application of the proposed method is provided.

Identification, expression analysis, and the regulating function on C/EBPs of KLF10 in Dalian purple sea urchin, Strongylocentrotus nudus.

Accumulating evidence indicates that Krüppel-like factors (KLFs) play important roles in fat biology via the regulation of CCAAT/enhancer binding proteins (C/EBPs). However, KLFs and C/EBPs have not been identified from Strongylocentrotus nudus, and their roles in this species are not clear. In this study, the full-length cDNA of S. nudus KLF10 (SnKLF10) and three cDNA fragments of S. nudus C/EBPs (SnC/EBPs) were obtained. Examination of tissue distribution and expression patterns during gonadal development implied that SnKLF10 and SnC/EBPs play important roles in gonadal lipogenesis. The presence of transcription factor-binding sites (TFBSs) for KLFs in SnC/EBPs, and the results of an over-expression assay, revealed that SnKLF10 negatively regulates the transcription of SnC/EBPs. In addition, the core promoter regions of SnC/EBPs were determined, and multiple TFBSs for transcription factor (TFs) were identified, which are potential regulators of SnC/EBP transcription. Taken together, these results suggest that SnC/EBP genes are potential targets of SnKLF10, and that SnKLF10 plays a role in lipogenesis by repressing the transcription of SnC/EBPs. These findings provide information for further studies of KLF10 in invertebrates and provide new insight into the regulatory mechanisms of C/EBP transcription.

De novo transcriptome sequencing and comparative analysis to discover genes involved in ovarian maturity in Strongylocentrotus nudus.

Strongylocentrotus nudus is an edible sea urchin, mainly harvested in China. Correlation studies indicated that S. nudus with larger diameter have a prolonged marketing time and better palatability owing to their precocious gonads and extended maturation process. However, the molecular mechanism underlying this phenomenon is still unknown. Here, transcriptome sequencing was applied to study the ovaries of adult S. nudus with different shell diameters to explore the possible mechanism. In this study, four independent cDNA libraries were constructed, including two from the big size urchins and two from the small ones using a HiSeq™2500 platform. A total of 88,581 unigenes were acquired with a mean length of 1354bp, of which 66,331 (74.88%) unigenes could be annotated using six major publicly available databases. Comparative analysis revealed that 353 unigenes were differentially expressed (with log2(ratio)≥1, FDR≤0.001) between the two groups. Of these, 20 differentially expressed genes (DEGs) were selected to confirm the accuracy of RNA-seq data by quantitative real-time RT-PCR. Furthermore, gene ontology and KEGG pathway enrichment analyses were performed to find the putative genes and pathways related to ovarian maturity. Eight unigenes were identified as significant DEGs involved in reproduction related pathways; these included Mos, Cdc20, Rec8, YP30, cytochrome P450 2U1, ovoperoxidase, proteoliaisin, and rendezvin. Our research fills the gap in the studies on the S. nudus ovaries using transcriptome analysis.

Identification and profiling of sex-biased microRNAs from sea urchin Strongylocentrotus nudus gonad by Solexa deep sequencing.

MicroRNAs (miRNAs) are a class of endogenous small non-coding RNAs that regulate gene expression by post-transcriptional repression of messenger RNA. The echinoderm, Strongylocentrotus nudus, is an excellent model organism for studying development and commercially important as a food source. However, to date no miRNAs have been reported to modulate sex gonad differentiation in S. nudus. In this study, we constructed two small RNA libraries from male and female S. nudus gonad respectively for Solexa sequencing. A total of 184 miRNAs including 60 known and 124 novel miRNAs were identified from the two libraries. Furthermore, the nucleotide bias and end variation of the known miRNAs were also analyzed. In addition, 67 differently expressed of the 86 co-expressed and 98 gender-specific (47 male-specific and 51 female-specific) miRNAs that may be involved in sexual differentiation were found by comparing the miRNA expression profiles in the two libraries. This study reveals the first miRNA profile related to the gonad differentiation of the S. nudus. This study gives a first insight into sex differences in miRNA expression of sea urchin which could facilitate studies of the reproductive organ-specific roles of miRNAs.

Identification and characterization of piRNA-like small RNAs in the gonad of sea urchin (Strongylocentrotus nudus).

Piwi-interacting RNAs (piRNAs) and their partner PIWI proteins play an essential role in fertility, germline stem cell development, as well as the basic control and evolution of animal genomes. However, research was rare with regard to piRNA population in sea urchin, a model animal intensively used for development and genetics studies. Utilizing Solexa sequencing, we present an identification of 13,051 piRNA-like RNAs expressed in male gonad of Strongylocentrotus nudus. Out of 202 tested RNAs, 94 sequences were confirmed to express in female gonad using microarray assay, suggesting that both male and female gonads are piRNA-like RNA-enriched organs. These RNAs with "U" at the 5' end or "A" at position of 10, in size from 26 to 30 nucleotides, were predominantly 28 nt in length and tend to be clustered in small regions in genome, achieving the longest piRNA-like RNA-enriched region about 5.5 kb in scaffold78427. Alignment results showed 11 RNAs were homologous to the known piRNAs. Furthermore, BLASTn searching against sea urchin repeat element database showed these piRNA-like RNAs matched to 101 types of DNA transposons and retrotransposons, of which SPRP1, Harbinger-N2, piggyBac-N10, SINE2-1, and piggyBac-N11 were the most frequent hit elements, suggesting a transposon silencing function of these piRNA-like RNAs.

Novel and conserved micrornas in Dalian purple urchin (Strongylocentrotus nudus) identified by next generation sequencing.

MicroRNAs are regulators in regulation of broad range of phenotypes. The purple urchin, Strongylocentrotus nudus, is one of the most important marine economic animals that widely distributed in the cold seas along the coasts of eastern pacific area. To date, only 45 microRNAs have been identified in a related species, Strongylocentrotus purpurtus, and there is no report on S. nudus microRNAs. Herein, solexa sequencing technology was used to high throughput sequencing analysis of microRNAs in small RNA library isolated from five tissues of S. nudus. Totally, 8,966,865 reads were yielded, 131,015 of which were related to 415 unique microRNAs including 345 deuterostoma conserved and 70 urchin specific microRNAs, as well as 5 microRNA* sequences. The miRNA features including length distribution, end variations and genomic locations were characterized. Annotation of targets revealed a broad range of biological processes and signal transduction pathways that regulated by urchin miRNAs, of which signal transduction mechanisms was the subgroup containing the maximum targets. In addition, the expression of 100 miRNAs in female gonad was confirmed using microRNA microarray analysis. This study provides a first large scale cloning and characterization of S.nudus miRNAs and their potential targets, providing the foundation for further characterization for their role in the regulation of diversity of physiological processes.

[Content of rare earth elements in wild Hypericum japonicum Thunb].

Rare earth elements are important nutritional elements for human health, and today more and more attention has been paid to the effective components in Chinese traditional medicine, especially to rare earth elements. Fifteen rare earth elements in wild hypericum japonicum Thunb were analyzed by the methods of ICP-MS. The results showed that the concentrations of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb, Tm, Lu and Y ranged from 6 ng x g(-1) x DW to 14 522 ng x g(-1) x DW, and among them the concentrations of La, Ce and Nd were higher than 2 000 ng x g(-1) x DW. Compared with the concentration of rare earth elements in rice, corn, wheat and barley, the total concentration of rare earth elements in hypericum japonicum Thunb was much higher, which could be the mechanism of curative effect of hypericum japonicum Thunb on liverish diseases. The character of elements and the content of rare earth elements in soil should be responsible for the difference, but the distributive mechanism of rare earth elements in hypericum japonicum Thunb should be further studied.

[Effects of hair dyeing on the heavy metals content in hair].

Cosmetic and hair dye has been one of the pollution resources of heavy metals. Contents of heavy metals in hair of dyed group and non-dyed group were analyzed by ICP-MS, the results showed that dyeing hair can change the content of heavy metals in hair, but the degree of effect is different for different element: contents of Mn, Fe, Ni, Cu, Cd and Sb in hair of dyed group were higher than that of non-dyed group, but contents of As, Cr, Zn, Ag, Pb and Hg were lower. The cause of the above results could be that hair dye contains more Mn, Fe, Ni, Cu, Cd and Sb, but less As, Cr, Zn, Ag, Pb and Hg, and dyeing hair could restrain the metabolism and excretion of As, Cr, Zn, Ag, Pb and Hg from human body.

[Application of ICP-MS to detect rare elements in wild Cistanche deserticola Y. C. Ma].

Rare metals are important nutritional elements for human health. Fifteen rare metals in wild Cistanche deserticola Y. C. Ma were analyzed by the methods of ICP-MS. The results showed that concentrations of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Yb and Lu in Wild Cistanche deserticola Y. C. Ma were 144.89, 259.75, 36.41, 133.25, 25.38, 6.10, 30.20, 3.85, 20.36, 3.42, 8.55, 6.42, 1.15, 20.02 and 29.77 ng x g(-1) respectively, the character of elements and the content of rare earth elements in soil should be responsible for the difference, but the mechanism of distribution should be further studied.

188Re-labeled MPEG-modified superparamagnetic nanogels: preparation and targeting application in rabbits.

Polyacrylamide-coated magnetic nanogels were synthesized via photochemical method in surfactants and initiators free aqueous system at room temperature. After Hoffmann elimination of carbonyl and further modification with methoxy poly(ethylene glycol) (MPEG), the MPEG-modified superparamagnetic nanogels (MSN) with better hydrophilicity and biocompatibility were obtained. The MSN were characterized by FTIR, XRD, SEM and PCS. Covalently linked with 188Re complex, the 188Re-labeled MSN were prepared and intravenously injected into the left ears of the anesthetized rabbits in control group (without external magnetic field) or in targeting group (in presence of external magnetic field). The average radioactivity distribution of organs in control group was detected and the magnetic targeting feature was investigated in targeting group.

[Determination of major elements in soil from cancer village by X-ray fluorescence spectrometry].

Many social problems arise from environmental pollution, cancer village is one of the many important problems caused by pollution. The authors selected a typical cancer village where 80-100 people died of cancer in the last five years, but there are only a total of 1 200 people in this village. The authors sampled soils from crops-planted areas and detected the major elements by X-ray fluorescence spectrometry. The results showed that the contents of SiO2, TiO2, Al2O3, Fe2O3, MnO, MgO, CaO, Na2O, K2O and P2O5 in soil of this village were 66.05%, 0.66%, 11.37%, 3.93%, 0.075%, 1.97%, 5.47%, 1.90%, 2.11% and 0.20% respectively; with the precision being +/- 0.20%, +/- 0.005%, +/- 0.10%, +/- 0.10%, +/- 0.005%, +/- 0.05%, +/- 0.04%, +/- 0.08%, +/- 0.02% and +/- 0.005% respectively, which showed that X-ray fluorescence spectrometry is a good method.