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31.
More than 98 percent of children in Finland attend preschool, where different kinds of projects are carried out in order to strengthen the children's abilities. This article focuses on the effects of one arts education project from a school readiness point of view. The main question was, How did the Helsinki arts education project affect the children's learning skills and attitudes? The target groups were children aged three to nine years who participated in the arts project in day care centers and schools. A multidimensional evaluation method was used for the analyses. The research data consisted of interviews of the program artists and educators (n = 23), follow-up reports (n = 9), and other materials. The results show that the program motivated children and aroused their interest in thinking, problem-solving, practicing, and learning. It offered children opportunities to experience success, which increased their self-confidence and skills. The project also strengthened their abilities in listening, goal-oriented work, evaluating others’ work, and receiving feedback, which are all abilities required for school entrance. The subject matter of their school courses was also integrated into their achievements.  相似文献   
32.
The effect of genotype, the origin of genotype, and germination temperature on Scots pine pollen grain size, hydration rate, germinability, and tube growth was studied in vitro. The mean sizes of dry and germinated pollen grains varied among pollen genotypes in different ways, thus the hydration rate varied among genotypes. Pollen from Scots pine that originates in northern Finland hydrated more than pollen from a population in southern Finland. Germination temperature had no effect on the hydration rate. Germinability and tube growth rate of northern genotypes were higher at 20 °C than at 15 °C. Differences among southern genotypes were not significant. At 15 °C, the germinability and pollen tube growth rate of northern genotypes were lower than southern genotypes. At 20 °C, the differences were not significant. It appears that germination and growth of pollen from northern populations are enhanced at higher temperatures whereas pollen from southern populations is unaffected.  相似文献   
33.
To evaluate the significance of progesterone and estradiol in human uterine activity during pregnancy and delivery the blood concentrations of these hormones were monitored weekly during the last trimester of pregnancy and at the onset of labour in 15 women, and before and 3 hours after the induction of term delivery in 83 parturients. Neither plasma concentrations of progesterone or estradiol nor the ratio of progesterone to estradiol changed significantly during the last trimester of pregnancy or at the onset of delivery. After the induction of delivery parturients with initial progesterone dominance (ratio of progesterone to estradiol higher than 5 before induction) demonstrated a significant fall in serum concentration of progesterone and in the ratio of progesterone to estradiol while estradiol concentration rose significantly. In estrogen dominant women (progesterone to estradiol ratio equal to or lower than 5) the serum concentration of progesterone and the ratio of progesterone to estradiol rose significantly during the 3 hours after the induction of delivery. Our results suggest that the peripheral blood levels of progesterone and estradiol do not correlate with the tissue biochemical changes which prepare the uterine cervix and myometrium for delivery. The observation that the ratio of progesterone to estradiol decreased in progesterone-dominant and increased in estrogen-dominant women stresses the importance of a well balanced equilibrium of these hormones for prostaglandin metabolism during human delivery.  相似文献   
34.
A molecular phylogenetic hypothesis is presented for the anoplocephaline cestodes of placental mammals based on sequence data from the mitochondrial cytochrome c oxidase I (COI) gene, the nuclear-encoded 28S rRNA gene and the internal transcribed spacer region I of rRNA (ITS1). The material consists of 35 species representing nine genera of cestodes, with emphasis on taxa parasitising rodents and lagomorphs in the Holarctic region. The resulting phylogenies show considerable disagreement with earlier systematic and phylogenetic hypotheses derived from morphology. Specifically, the results contradict the view of uterine morphology being the primary determinant of deeper phylogenetic splits within Anoplocephalinae. Also, the role of genital duplication as a means of generic divergence was not found to follow consistently the pattern suggested by earlier hypotheses. Colonisation of novel host lineages has evidently been the predominant mode of diversification in anoplocephaline cestodes of placental mammals; evidence for phyletic co-evolution was obscure. The phylogenies consistently distinguished a large monophyletic group including all species from arvicoline rodents (voles and lemmings), primarily representing the genera Anoplocephaloides Baer, 1923 and Paranoplocephala Lühe, 1910. Phylogenetic relationships within the “arvicoline clade” of cestodes were generally poorly resolved. Consistent support for nodes above and below the unresolved polytomy indicates a rapid radiation involving a nearly simultaneous diversification of many lineages, a scenario also proposed for the arvicoline hosts.  相似文献   
35.
Naproxen tablets and suppositories were compared, in the treatment of primary dysmenorrhea, in a double-blind cross-over trial. The results on 32 patients treated during 128 menstruations with either tablets and suppositories were analysed. Both naproxen tablets and suppositories produced a significant but similar overall relief of dysmenorrhea, although the tablets had a better effect in relieving spasmodic pain than the suppositories (p < 0.05). Occasions of failure to obtain relief were not related to the occurrence of vomiting or diarrhea during the trial. Vomiting seems not to be responsible for the therapeutic failures of oral treatments with prostaglandin-synthetase inhibitors in primary dysmenorrhea.  相似文献   
36.
B-function genes determine the identity of petals and stamens in the flowers of model plants such as Arabidopsis and Antirrhinum . Here, we show that a putative B-function gene BpMADS2 , a birch homolog for PISTILLATA , is expressed in stamens and carpels of birch inflorescences. We also present a novel birch gene BpMADS8 , a homolog for APETALA3 / DEFICIENS , which is expressed in stamens. Promoter-GUS analysis revealed that BpMADS2 promoter is active in the receptacle of Arabidopsis flower buds while BpMADS8 promoter is highly specific in mature stamens. BpMADS2 promoter:: BARNASE construct prevented floral organ development in Arabidopsis and tobacco. In birch, inflorescences with degenerated stamens and carpels were obtained. BpMADS8::BARNASE resulted in degeneration of stamens in Arabidopsis and birch causing male sterility. In tobacco, only sepals were developed instead of normal flowers. The results show that the BpMADS2::BARNASE construct can be used to specifically disrupt floral organ development in phylogenetically distant plant species. The stamen-specific promoter of BpMADS8 is a promising tool for biotechnological applications in inducing male sterility or targeting gene expression in the late stamen development.  相似文献   
37.
Birds need to acquire carotenoids for their feather pigmentation from their diet, which means that their plumage color may change as a consequence of human impact on their environment. For example, the carotenoid-based plumage coloration of Great tit, Parus major, nestlings is associated with the degree of environmental pollution. Breast feathers of birds in territories exposed to heavy metals are less yellow than those in unpolluted environments. Here we tested two hypotheses that could explain the observed pattern: (I) deficiency of carotenoids in diet, and (II) pollution-related changes in transfer of carotenoids to feathers. We manipulated dietary carotenoid levels of nestlings and measured the responses in plumage color and tissue concentrations. Our carotenoid supplementation produced the same response in tissue carotenoid concentrations and plumage color in polluted and unpolluted environments. Variation in heavy metal levels did not explain the variation in tissue (yolk, plasma, and feathers) carotenoid concentrations and was not related to plumage coloration. Instead, the variation in plumage yellowness was associated with the availability of carotenoid-rich caterpillars in territories. Our results support the hypothesis that the primary reason for pollution-related variation in plumage color is carotenoid deficiency in the diet.  相似文献   
38.
39.
Listeria monocytogenes is a food‐borne pathogen that uses actin‐dependent motility to spread between human cells. Cell‐to‐cell spread involves the formation by motile bacteria of plasma membrane‐derived structures termed ‘protrusions’. In cultured enterocytes, the secreted Listeria protein InlC promotes protrusion formation by binding and inhibiting the human scaffolding protein Tuba. Here we demonstrate that protrusions are controlled by human COPII components that direct trafficking from the endoplasmic reticulum. Co‐precipitation experiments indicated that the COPII proteins Sec31A and Sec13 interact directly with a Src homology 3 domain in Tuba. This interaction was antagonized by InlC. Depletion of Sec31A or Sec13 restored normal protrusion formation to a Listeria mutant lacking inlC, without affecting spread of wild‐type bacteria. Genetic impairment of the COPII component Sar1 or treatment of cells with brefeldin A affected protrusions similarly to Sec31A or Sec13 depletion. These findings indicated that InlC relieves a host‐mediated restriction of Listeria spread otherwise imposed by COPII. Inhibition of Sec31A, Sec13 or Sar1 or brefeldin A treatment also perturbed the structure of cell–cell junctions. Collectively, these findings demonstrate an important role for COPII in controlling Listeria spread. We propose that COPII may act by delivering host proteins that generate tension at cell junctions.  相似文献   
40.
Using the ITS region and the gene tef1, 23 strains of the genus Trichoderma were identified as belonging to the species T. harzianum (n = 14), T. olivascens (n = 1), T. trixiae (n = 1), T. viridialbum (n = 1), T. tomentosum (n = 2), T. koningii (n = 1), T. atroviride (n = 1), T. viride (n = 1), and T. gamsii (n = 1). Strains expressing extracellular laccase activity were selected by decolorization/oxidation assays in solid media, using azo, anthraquinone, indigoid, and triphenylmethane dyes, and the phenolic substances tannic acid and guaiacol. No strain decolorized Direct Blue 71 or Chicago Blue 6B, but all of them weakly oxidized guaiacol, decolorized Methyl Orange, and efficiently oxidized tannic acid. Based in decolorization/oxidation assays, strains CMU‐1 (T. harzianum), CMU‐8 (T. atroviride), CMU‐218 (T. viride), and CMU‐221 (T. tomentosum) were selected for evaluating their extracellular laccase activity in liquid media. Strain CMU‐8 showed no basal laccase activity, while strains CMU‐1, CMU‐218, and CMU‐221 had a basal laccase activity of 1,313.88 mU/mL, 763.88 mU/mL, and 799.53 mU/mL, respectively. Addition of sorghum straw inhibited laccase activity in strain CMU‐1 by 34%, relative to the basal culture, while strains CMU‐8, CMU‐21, and CMU‐221 increased their laccase activity by 1,321.5%, 64%, and 47%, respectively. These results show that assayed phenolic substrates are good tools for selecting laccase producer strains in Trichoderma. These same assays indicate the potential use of studied strains for bioremediation processes. Straw laccase induction suggests that analyzed strains have potential for straw delignification in biopulping and other biotechnological applications. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:787–798, 2016  相似文献   
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