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1.
Coordination polymers of HEAP-ED with La(III), Pr(III), Nd(III), Sm(III), Gd(III), Tb(III) and Dy(III) metal ions have been synthesized and characterized by elemental analyses, electronic spectra, magnetic susceptibilities, FTIR, NMR, scanning electronic microscopy (SEM) and thermogravimetric analyses. Catalytic activity of selected coordination polymers was examined for pharmaceutical important organic synthesis. Antimicrobial activity of isolated Ln(III) coordination polymers against Escherichia coli, Bacillus subtilis, Staphylococcus aureus (bacteria) and Saccharomyces cerevisiae (yeast) were measured. It was observed from the study that the Ln(III) coordination polymers acted as an efficient and effective catalysts and antimicrobial agents.  相似文献   
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As part of a selection strategy for artificial nucleic acids (XNA) (to be considered as potential new information systems in vivo), we have carried out a modelling study on cyclohexanyl nucleic acids (CNA) duplexes and hairpins. CNA may form a duplex as well as hairpin structures, having the carbocyclic nucleosides in the 4C1 conformation (with equatorial basis). The geometry of ds CNA is close to that of a HNA:RNA duplex. We demonstrated that CNA triphosphates function as a substrate for polymerases. Modelling experiments indicate that the monomers are probably presented to the polymerase in the 1C4 conformation.  相似文献   
4.
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Highlights
  • •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
  • •Using patient derived xenograft (PDX) tumors can overcome this limitation.
  • •The large PDX HLA peptidomes expand significantly those of the original biopsies.
  • •The HLA peptidomes of the PDX tumors included many tumor antigens.
  相似文献   
5.
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Highlights
  • •MS-based clinical assay that accurately determines phospho Rab10 occupancy.
  • •Stable isotope labeled phosphopeptide injected as a standard with endogenous tryptic phospho Rab peptide for accurate ratio determination.
  • •Determination of pRab levels in neutrophils of Parkinson disease patients.
  • •Relevance of pRab levels as marker of PD.
  相似文献   
6.
《Anthrozo?s》2013,26(2):150-165
Abstract

This paper describes a field study on the effects of attachment styles on the subjective well-being of institutionalized older persons after participating in a pet visitation program. We compared how attachment style (i.e., secure, anxious ambivalent, dismissive avoidant, and fearful avoidant) moderated the impact of a dog visitation program in 52 elderly residents of an assisted-living facility. Controlling for pre-visitation mood, the results revealed that the secure style related to increases in positive mood after interacting with the dogs. The anxious ambivalent style related to increases in positive mood and decreases in ratings of depression. Most importantly, the fearful avoidant style related to increases in depression after interacting with the dogs. The results highlight the notion that not all participants benefit from taking part in pet visitation programs. Theoretically, this study presents preliminary evidence for the relevance of attachment styles in understanding human–pet interactions.  相似文献   
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In a typical comparative clinical trial the randomization scheme is fixed at the beginning of the study, and maintained throughout the course of the trial. A number of researchers have championed a randomized trial design referred to as ‘outcome‐adaptive randomization.’ In this type of trial, the likelihood of a patient being enrolled to a particular arm of the study increases or decreases as preliminary information becomes available suggesting that treatment may be superior or inferior. While the design merits of outcome‐adaptive trials have been debated, little attention has been paid to significant ethical concerns that arise in the conduct of such studies. These include loss of equipoise, lack of processes for adequate informed consent, and inequalities inherent in the research design which could lead to perceptions of injustice that may have negative implications for patients and the research enterprise. This article examines the ethical difficulties inherent in outcome‐adaptive trials.  相似文献   
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Aim Species capable of vigorous growth under a wide range of environmental conditions should have a higher chance of becoming invasive after introduction into new regions. High performance across environments can be achieved either by constitutively expressed traits that allow for high resource uptake under different environmental conditions or by adaptive plasticity of traits. Here we test whether invasive and non‐invasive species differ in presumably adaptive plasticity. Location Europe (for native species); the rest of the world and North America in particular (for alien species). Methods We selected 14 congeneric pairs of European herbaceous species that have all been introduced elsewhere. One species of each pair is highly invasive elsewhere in the world, particularly so in North America, whereas the other species has not become invasive or has spread only to a limited degree. We grew native plant material of the 28 species under shaded and non‐shaded conditions in a common garden experiment, and measured biomass production and morphological traits that are frequently related to shade tolerance and avoidance. Results Invasive species had higher shoot–root ratios, tended to have longer leaf‐blades, and produced more biomass than congeneric non‐invasive species both under shaded and non‐shaded conditions. Plants responded to shading by increasing shoot–root ratios and specific leaf area. Surprisingly, these shade‐induced responses, which are widely considered to be adaptive, did not differ between invasive and non‐invasive species. Main conclusions We conclude that high biomass production across different light environments pre‐adapts species to become invasive, and that this is not mediated by plasticities of the morphological traits that we measured.  相似文献   
9.
The effects of repeated annual application of methiocarb-based slug pellets, broadcast on the soil surface and drilled into the seed bed, on carabid beetle activity were investigated over a four year period on a winter-sown cereal field using pitfall traps in barriered plots. Following applications in late autumn all winter-active carabid populations were severely depressed; total carabid activity falling to less than 5% and 10–15% following broadcast and drilled applications, respectively, compared with untreated plots. Spring and summer-active species, not active at the time of application, were largely unaffected by applications and were responsible for a gradual recovery of total activity from early spring onwards. Activity of all affected winter species remained demonstrably depressed on treated areas for the remainder of their seasonal incidence. However, all except one species, Bembidion obtusum, recovered to normal activity levels in the following season prior to reapplication. Recovery patterns are discussed in terms of the known biology of the species involved. Evidence that a minority of summer-active species were also affected by treatments, sometimes positively and sometimes negatively, were attributed to indirect effects possibly involving prey availability and foraging behaviour. The long-term ecological and short-term agronomic implications of methiocarb effects on carabid populations in winter-sown cereals are discussed.  相似文献   
10.
Summary The effect of artificial acid rain on the reproduction and survival of the aphid Euceraphis betulae on silver birch was studied in Turku, southern Finland. Eight bioassays were done during 1984–1986. In four of the bioassays the aphids produced 40% to over 100% more progeny on birches watered with dilute sulphuric acid (pH 3.5) than on control trees. In four other cases the performance of aphids did not differ between the treatments. An index of aphid reproduction pooled over the whole study was significantly higher on acid-treated than on control birches. The reproduction of aphids on acid-treated birches was enhanced when precipitation was below long term average, suggesting an interaction between the stress caused by acid treatment and dry periods.  相似文献   
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