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41.
A new oribatid mite species, Rhynchoribates parafabulosus sp. n., is described from Ecuador. This species is similar to R. fabulosus Beck 1961 (from Peru) in the rostrum structure and the length of prodorsal and notogastral setae. However, it clearly differs from the above species by the absence of thorns on the leg femora, location of adanal lyrifissures, and the structure of notogastral setae. 相似文献
42.
One-dimensional polyacrylamide gel electrophoresis (1D PAGE) followed by immunoblotting revealed genetic polymorphism of GC protein in sheep (variants F, S, V) and mouflon (variants F and S, apparently identical to F and S of sheep). The frequency of Gcs allele ranged from 0.84 to 1.0 in the 12 breeds of sheep studied. GcV allele was observed only in Tsigai breed with a frequency of 0.017. 相似文献
43.
Ulrich Heink Ann Van Herzele Györgyi Bela Ágnes Kalóczkai Kurt Jax 《Biodiversity and Conservation》2018,27(7):1659-1677
The prevention and management of invasive alien species (IAS) has become a high priority in European environmental policy. At the same time, ways of evaluating IAS continue to be a topic of lively debate. In particular, it is far from clear how directly policy makers’ value judgements are linked to the European (EU) policy against IAS. We examine the arguments used to support value judgements of both alien species and invasive alien species as well as the relation between these value judgements and the policy against IAS being developed at European level. Our study is based on 17 semi-structured interviews with experts from EU policy making and from the EU member states Austria, Belgium, Germany and Hungary. We found that our interviewees conceived of IAS in very different ways, expressed a variety of visions of biodiversity and ecosystem services, and adhered to widely different values expressed in their perceptions of IAS and the impacts of IAS. However, only some of these conceptualizations and value judgements are actually addressed in the rationale given in the preamble to the European IAS Regulation. Although value judgements about IAS differed, there was considerable agreement regarding the kind of action to be taken against them. 相似文献
44.
In vivo release of dopa and dopamine from genetically engineered cells grafted to the denervated rat striatum 总被引:9,自引:0,他引:9
Fibroblastic 3T3 and endocrine RIN cells were genetically modified by infection with a recombinant retrovirus encoding the form I of human tyrosine hydroxylase (TH) and selection in tyrosine-free medium. These cells were grafted to rats unilaterally lesioned with 6-hydroxy-dopamine. Both cell types survived implantation into the striatum, expressed TH immunoreactivity, and as assessed by microdialysis 8-9 days after implantation, secreted high amounts of DOPA and/or dopamine into the surrounding host striatum. The modified 3T3 cells secreted large amounts of DOPA that was efficiently decarboxylated to dopamine by the host striatal tissue; the newly synthesized dopamine was stored only to a limited extent in the denervated striatum. The modified RIN cells synthesized dopamine that was stored intracellularly and released in a regulated fashion. The grafted DOPA-secreting cells produced 4-5 times higher extracellular dopamine levels than the dopamine-secreting cells, and they were more efficient in reducing apomorphine-induced rotation. No effect was observed with either cell type on amphetamine-induced turning behavior. 相似文献
45.
Robert L Conhaim Kal E Watson Dennis M Heisey Glen E Leverson Bruce A Harms 《Journal of applied physiology》2004,96(1):245-252
Effects of vasoconstriction on the distribution of perfusion among alveoli are not well understood. To address this, we used a new method we developed to determine how microvascular perfusion distribution was affected by a potent vasoconstrictor, the thromboxane receptor analog U-46619. Our method was to infuse 4-microm-diameter fluorescent latex microspheres into the circulation of isolated rat lungs vasoconstricted with U-46619. We used a confocal microscope to image trapping patterns of the particles in dried sections of the lungs and then used dispersion index analysis to quantify the particle patterns in the images, which encompassed approximately 2,000 alveoli. Dispersion indexes revealed significantly more particle clustering (inhomogeneous distribution) in vasoconstricted lungs than in normal flow controls or in controls in which flow was reduced by either lowering pulmonary arterial pressure or raising left atrial pressure. These results suggest that vasoconstriction occurred in the microvessels themselves, which are much smaller vessels than those previously thought to be capable of vasoconstriction. 相似文献
46.
Influence of initiator and different polymerisation conditions on performance of molecularly imprinted polymers 总被引:1,自引:0,他引:1
Mijangos I Navarro-Villoslada F Guerreiro A Piletska E Chianella I Karim K Turner A Piletsky S 《Biosensors & bioelectronics》2006,22(3):381-387
A set of polymers was imprinted with (-)-ephedrine using two different initiators. A chemometrics approach was used to optimise experiments aimed at analysis of the interplay of parameters such as polymerisation time, temperature and percentage of initiator. The results presented demonstrate the importance of keeping the right balance between these various parameters of polymerisation conditions. It is shown that enhancing one single parameter such as polymer rigidity does not necessarily improve polymer performance. In general it could be concluded that MIPs should be synthesised over a long period of time using low concentration of initiator and low temperature. The best selectivity was achieved for polymers prepared by photo-initiation with 2,2-dimethoxy-2-phenylacetophenone as initiator. 相似文献
47.
Margaret E. Kruk Andreas Wladis Naboth Mbembati S. Khady Ndao-Brumblay Renee Y. Hsia Moses Galukande Sam Luboga Alphonsus Matovu Helder de Miranda Doruk Ozgediz Ana Romàn Qui?ones Peter C. Rockers Johan von Schreeb Fernando Vaz Haile T. Debas Sarah B. Macfarlane 《PLoS medicine》2010,7(3)
Background
There is a growing recognition that the provision of surgical services in low-income countries is inadequate to the need. While constrained health budgets and health worker shortages have been blamed for the low rates of surgery, there has been little empirical data on the providers of surgery and cost of surgical services in Africa. This study described the range of providers of surgical care and anesthesia and estimated the resources dedicated to surgery at district hospitals in three African countries.Methods and Findings
We conducted a retrospective cross-sectional survey of data from eight district hospitals in Mozambique, Tanzania, and Uganda. There were no specialist surgeons or anesthetists in any of the hospitals. Most of the health workers were nurses (77.5%), followed by mid-level providers (MLPs) not trained to provide surgical care (7.8%), and MLPs trained to perform surgical procedures (3.8%). There were one to six medical doctors per hospital (4.2% of clinical staff). Most major surgical procedures were performed by doctors (54.6%), however over one-third (35.9%) were done by MLPs. Anesthesia was mainly provided by nurses (39.4%). Most of the hospital expenditure was related to staffing. Of the total operating costs, only 7% to 14% was allocated to surgical care, the majority of which was for obstetric surgery. These costs represent a per capita expenditure on surgery ranging from US$0.05 to US$0.14 between the eight hospitals.Conclusion
African countries have adopted different policies to ensure the provision of surgical care in their respective district hospitals. Overall, the surgical output per capita was very low, reflecting low staffing ratios and limited expenditures for surgery. We found that most surgical and anesthesia services in the three countries in the study were provided by generalist doctors, MLPs, and nurses. Although more information is needed to estimate unmet need for surgery, increasing the funds allocated to surgery, and, in the absence of trained doctors and surgeons, formalizing the training of MLPs appears to be a pragmatic and cost-effective way to make basic surgical services available in underserved areas. Please see later in the article for the Editors'' Summary 相似文献48.
Jan Frouz Rudy Van Diggelen Vaclav Pižl Josef Starý Ladislav Háněl Karel Tajovský Jiří Kalčík 《Biodiversity and Conservation》2009,18(14):3963-3978
Communities of soil macrofauna, oribatid mites, and nematodes as well as vegetation and soil chemistry were studied on twelve
plots representing three replicates of the following treatments: agricultural meadow, heathland, and heathland restored either
by partial or complete topsoil removal 15 years earlier. We also studied the effect of soil macrofauna on decomposition and
the microstructure of the soil surface layer with litterbags in combination with the analysis of thin soil sections. The communities
of soil macrofauna and oribatid mites significantly differed between agricultural meadows and heathlands. The partial and
complete topsoil removal plots were more similar to heathlands with respect to macrofauna and to agricultural meadows with
respect to oribatid mites. The density and diversity of soil macrofauna was higher in agricultural meadows than in heathlands;
in particular, earthworms, litter transformers, root feeders, and microsaprophags were more abundant on meadows. Heathlands,
in contrast, contained a much higher diversity of oribatid mites. The community structure of nematodes did not significantly
differ among the treatments. Analysis of thin soil sections revealed a thick organic fermentation layer in heathlands, which
was absent in agricultural meadows and only weakly developed in the topsoil removal plots. In agricultural meadows, litterbags
and thin soil sections indicated that abundant macrofauna, including endogeic earthworms, were very effective in removing
the litter from the soil surface and mixing it into the mineral soil. Possible effects of this soil mixing on restoration
success are discussed. 相似文献
49.
This study explored processes responsible for environmental heterogeneity at a man-made post-mining landscape formed by heaping of homogeneous overburden in longitudinal “waves”. Soil chemistry (pH; conductivity; total C; total, available, and water-soluble P; and available K, Na, and Ca), the distribution of woody and herbaceous plants, litter quantity, and the distribution of soil fauna were studied along a100-m transect. Heterogeneity between waves was very low, and only available P and biomass of herbaceous plants differed among waves. In contrast, all investigated parameters except of total and available P and fauna density differed among position inside waves. Woody plants were more numerous on the wave tops and slopes than on the bottoms. Distribution of shrubs between waves affect between-waves distribution of other parameters, namely soil Cox, as waves with more shrubs have larger litter input and more soil carbon. 相似文献
50.
Gomez-Caballero A Guerreiro A Karim K Piletsky S Goicolea MA Barrio RJ 《Biosensors & bioelectronics》2011,28(1):25-32
This paper reports the design of Molecularly Imprinted Polymers (MIP) with affinity towards (S)-citalopram using computational modeling for the selection of functional monomers and monomer:template ratio. Acrylamide was selected as functional monomer and the final complex functional monomer/template resulted in a 3:1 ratio. The polymer was synthesized by radical polymerization initiated by UV onto magnetic stir-bars in order to obtain a stir bar sorptive extraction (SBSE) device capable of selective enantiomeric recognition. After successful template removal, the parameters affecting the SBSE procedure (sample volume, ionic strength, extraction time and pH) were optimized for the effective rebinding of the target analyte. The resultant chirally imprinted polymer based stir-bar was able to selectively extract (S)-citalopram from a racemic mixture in an aqueous media with high specificity (specificity factor 4) between 25 and 500 μgL(-1). The MIP coated stir-bars can have significance for enantiospecific sample pre-concentration and subsequent analysis without the need for any chiral chromatographic separation. 相似文献