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Coordinated assembly of the ribosome is essential for proper translational activity in eukaryotic cells. It is therefore critical to coordinate the expression of components of ribosomal programs with the cell's nutritional status. However, coordinating expression of these components is poorly understood. Here, by combining experimental and computational approaches, we systematically identified box C/D snoRNAs in four fission yeasts and found that the expression of box C/D snoRNA and ribosomal protein (RP) genes were orchestrated by a common Homol-D box, thereby ensuring a constant balance of these two genetic components. Interestingly, such transcriptional coregulations could be observed in most Ascomycota species and were mediated by different cis-regulatory elements. Via the reservation of cis elements, changes in spatial configuration, the substitution of cis elements, and gain or loss of cis elements, the regulatory networks of box C/D snoRNAs evolved to correspond with those of the RP genes, maintaining transcriptional coregulation between box C/D snoRNAs and RP genes. Our results indicate that coregulation via common cis elements is an important mechanism to coordinate expression of the RP and snoRNA genes, which ensures a constant balance of these two components.

This study investigates how students perceived social loafing and social interdependence influence group learning performance through group affective tone in undergraduate hospitality and tourism curricula. A questionnaire survey was administered to collect data from college students majoring hospitality and tourism management at four Taiwanese universities. Of 660 distributed questionnaires, 634 questionnaires were returned, accounted for a 96 % response rate. To justify the aggregated individual data to the group level, this study used the within-group inter-rater agreement (r wg) to assess and determine 123 valid learning groups for data analysis. The analytical results show that group affective tone significantly mediates the effect of social loafing and social interdependence on group productivity, but not on group final grades. Specific implications and suggestions are also discussed.

Ni-doping TiO2 photocatalysts were synthesized by sol-gel method and characterized by XRD, Size Distribution and PL instruments. Meanwhile, the degradation of methyl blue (MB) was investigated under fluorescent lamp to test the photocatalytic activity of the samples with different Ni-doping concentration and sintered at different temperature. The results show that the photocatalytic activity of TiO2 photocatalysts is much higher than that of Degussa P25. The optimum preparation parameters are that the pH value is 2.5, Ni: Ti=0.01 (molar ratio) and sintering temperature is 500°C.

T-helper type 1 (Th1) immune response is involved in the development of protective immunity against Mycobacterium tuberculosis. Thus, an increase in Th1 and cellular immune responses should lead to enhanced anti-mycobacterial activity. In this study, we aimed to improve Th1 immune responses to a DNA vaccine by adding potentially immunostimulatory nucleotide sequences into the transcribed region downstream of the antigen. The Mycobacterium leprae gene for hsp65, codon-optimized for expression in mammalian cells, was inserted into pVAX1 with and without 3'-sequences containing CpG and dsRNA motifs. When the plasmid contained both motifs, transfected murine macrophage-like RAW264.7 cells showed markedly increased levels of mRNA for immune molecules of Th1 (IFN-α, IL-12) and Th17 (IL-17, IL-23 and IL-6) responses and for T cell co-stimulatory molecules (CD80 and CD86) but not for a Th2 response (IL-4 and IL-10). Immunized mice showed substantially increased serum anti-Hsp65 IgG2a antibody levels and IFN-γ production by spleen cells, confirming enhancement of the Th1 response in vivo. Furthermore, when non-vaccinated mice were infected with H37Rv by low-dose aerosol challenge, and then 4 weeks later were treated with plasmids by intramuscular injection, the mice that had been treated with plasmids containing immunostimulatory motifs showed an enhanced reduction in mycobacterial loads in lung and spleen. We conclude that DNA vaccines may be made more highly immunogenic and more effective for treatment by including transcribed stimulatory sequences.

Silicate strontium phosphor for white light LEDs was synthesized by high temperature solid-state method. The structure, surface, excitation and emission spectra of Sr3SiO5: Eu2+ phosphor which contain different mass fractions of BaF2 were measured. The results show that BaF2 quantity affects the structure, surface and spectra of Sr3SiO5: Eu2+ sample. The sample has the best properties when the BaF2 concentration comes to 2.0wt%. The structure of sample is tetragonal phase Sr3SiO5. The emission and excitation spectra peaks locate respectively at 575nm and 537nm. The samples can be excited by InGaN blue chip. The emission peaks appeared apparent red shift with the increase of BaF2 concentration. A white light emission spectrum with good color rendition was obtained by coupling the phosphor with blue chip.

A thermal insulating material is synthesized via a non-steam-cured and non-fired route by using fly-ash, sorel cement and hydrogen peroxide solution as raw material. Properties such as apparent density, compressive strength, bending strength, thermal conductivity, water resistance, and thermal tolerance of this matrial are studied, some influencing factors on its performance discussed. This material has an apparent density of 360 kg/m3, a compressive strength of 1.86 MPa, a thermal conduction coefficient of 0.072 W/(m·K), a softening coefficient of 0.55, and a thermal tolerant temperature of 300 °C. Test results show that this material is light in weight, of high strength, and good thermal insulation. In addition, neither steam-curing nor sintering is needed in producing it. Further more, large amount of fly ash is used in this material, making it a low cost and environment-friendly building material.

Dipteronia dyerana is a rare endemic from south-eastern Yunnan Province (China) that is known from only five natural populations, two of which occur outside a nature reserve. To obtain base-line information of the population structure, history and conservation of the species, we investigated patterns of genetic diversity within and among all natural populations, in addition to an ex situ conserved population, using inter-simple sequence repeat (ISSR) DNA markers. Across all populations surveyed, average within-population diversity was remarkably low (e.g., 0.088 for Nei's gene diversity), with populations from outside the nature reserve maintaining the highest amounts of genetic diversity. Among all natural populations, high genetic differentiation (G ST = 0.375) was detected, together with an isolation-by-distance pattern. Past habitat fragmentation, restricted gene flow and, to a lesser extent, genetic drift are proposed to be the determinant factors responsible for the low genetic diversity and high genetic differentiation observed, although reproductive-ecological factors, such as a mixed-mating system and low seedling recruitment due to inbreeding, might also play a role. We strongly recommend in situ conservation of those D. dyerana populations occurring outside the nature reserve, as they contain the highest proportion of the species' total ISSR fragment diversity, which might be eventually relevant for local adaptation. Our data further indicate that the ex situ conserved population insufficiently represents the genetic diversity present in the species. It is therefore suggested to sample at least four natural populations to cover a reasonable proportion (≥ 95%) of the species' genetic variation for ex situ conservation.

Considering all small nucleolar RNAs (snoRNAs) enriched in the nucleolus, we generated a specialized cDNA library of small nuclear RNAs from Schizosaccharomyces pombe and isolated, for the first time, 20 novel box H/ACA snoRNAs. Thirteen of these were characterized as novel guides that were predicted to direct 19 pseudouridylations in 18 S and 25 S rRNAs. The remaining seven snoRNAs were considered as orphan guides that lack sequence complementarity to either rRNAs or snRNAs. We have experimentally demonstrated the function of the 10 novel snoRNAs by gene deletion in the fission yeast. The snoRNAs were shown to be dispensable for the viability of S. pombe, although an impact of snR94 depletion on yeast growth, especially at 23 degrees C, was revealed. A total of 30 pseudouridylation sites were precisely mapped in the S. pombe rRNAs, showing a distinctive pseudouridylation pattern in the budding yeast. Interestingly, the absence of pseudouridylation on U2347 in S. pombe 25 S rRNA pointed out a critical role for Psi2345 in conferring a growth advantage for yeast. In contrast to the intron-encoded box C/D sno-RNAs in yeast, all box H/ACA snoRNAs appeared to be transcribed independently from intergenic regions between two protein-coding genes, except for snR35, which was nested in an open reading frame encoding for a hypothetical protein, although expressed from the opposite strand. Remarkably, snR90 was cotranscribed with an intron-encoded box C/D snoRNA, and this is the first demonstration of a non-coding RNA gene that encodes two different types of snoRNAs by its exon and intron. A detailed comparison of the S. pombe snoRNAs, with their functional homologues in diverse organisms, suggests a mechanism by which the snoRNAs have evolved in coordination with rRNAs to preserve the post-transcriptional modification sites among distant eukaryotes.

By constructing and screening theSchizosaccharomyces pombe nuclear cDNA library, a novel small nucleolar RNAs (snoRNA) was identified. The novel snoRNA displays structural features typical of C/D box snoRNA family and possesses a 10-nt-long rRNA antisense element which is predicted to guide the 2′-O-methylation of the fission yeast 25S rRNA at G940. As expected, the rRNA ribose-methylation site predicted by the novel snoRNA was precisely mapped by a deoxynucleoside triphosphate concentrationdependent primer extension assay. The comparison of functional element of guide snoRNAs among eukaryotes reveals that the novel snoRNA is a partial counterpart of the budding yeast snR60 and was termed snR60-II. snR60-II gene nested in the intron of a non-coding RNA gene with an unknown function, which is the first example of a yeast snoRNA encoded in an intron of a non-coding RNA gene. Furthermore, a number of yeast snR60 homologues were also identified from other fungi and fly. Our results reveal that snR60 exhibits diverse genomic organization in eukaryotes, implying the high mobility of snR60 gene in the course of evolution.

To explore the involvement of intron A into eukaryotic expression vector to improve antigen expression efficiency and enhance immunogenicity of DNA vaccine in mice.As model antigen, the coding gene of mycobacterial Hsp65 was cloned into eukaryotic expression vector pCMV4.0 with intron A involved and pVAX1 without intron A involved, respectively. The resulted recombinant expression vectors were transfected into 293T cells and were then injected into BALB/c mice as DNA vaccines. Anti-Hsp65 specific IgG and isotype were detected by ELISA and T cell immune response was analyzed by enzyme-linked immunosorbent spot (ELISPOT) assay and intracellular cytokine staining.Compared with non-intron A pVAX1hsp65, the recombinant plasmid pCMV4.0hsp65 involved with intron A pVAX1hsp65 caused higher expression level of Hsp65 in 293T cells, and enhanced Th1 type immune response, which was defined as higher level of anti-Hsp65 specific total IgG level (3.76 ± 0.23 vs 3.15 ± 0.22, P0.01) and IgG2a/IgG1 ratio (4.08 ± 0.04 vs 2.23 ± 0.12, P0.01) and more IFN-γ-secreting CD4(+) ((2.0 ± 0.058)% vs (1.5 ± 0.087)%, t = 4.804, P0.01) and CD8(+) ((0.6 ± 0.058)% vs (1.0 ± 0.115)%, t = 3.098, P0.05) T lymphocytes. The difference showed statistical significance.Intron A can improve the expression efficiency of mycobacterial Hsp65 antigen and enhance immunogenicity of DNA vaccine in mice when involved into eukaryotic expression vector.

Peroxisomes are essential for organisms' development and physiology. This fact is underscored by the lethality of a group of genetic disorders collectively known as the peroxisome biogenesis disorders (PBDs), such as Zellweger syndrome, in which peroxisomes fail to assemble properly. Defining the molecular bases of the PBDs has been the impetus behind the identification of the genes controlling peroxisome assembly, the PEX genes, from various modern organisms. Here as a original strain, Yarrowia lipolytica E122 was mutated by diethyl sulfate (DES) treatment and two mutants including temperature sensitive one were obtained. Compared to the initial strain, the two mutants showed more diffuse pattern of fluorescence characteristic of a cytosolic localization in immunofluorescence analysis, and showed no morphologically recognizable peroxisomes in electron micrographs. The two mutants arose from new gene mutation characterized by transformation and will be very useful in identification of new gene controlling peroxisome assembly from yeast.

Rhizomes of Sinopodophyllum hexandrum and Dysosma species, which have long been used in the traditional Chinese herbal medicine, have similar morphology and chemical composition. However, the podophyllotoxin content is higher in the rhizomes of S. hexandrum than in those of Dysosma species. The PCR-amplified fragments of trnT -trnL showed length variation between S. hexandrum and Dysosma species, and sequence comparison indicated that the length variation resulted from differential indels. There were species-specific PCR-RFLP markers of the chloroplast trnD -trnT region. Our results suggest that both chloroplast intergenic regions can be used for the identification of S. hexandrum and Dysosma Rhizoma medicines on the market.