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41.
42.
ABSTRACT

Due to negative health effects of high sodium intake, it is recommended to reduce the daily salt intake by around 50%. To reduce the sodium content, sodium salts can be exchanged with potassium or magnesium salts. The effect of sodium, potassium, and magnesium chlorides on extractability of proteins from fresh and frozen haddock muscle and minces was studied. Salting with KCl and MgCl2 instead of NaCl changed protein extractability. The highest solubility of the proteins was achieved using Na+. However, at low concentrations, extractability in K+ and Mg2+ is on the same level as Na+, showing that partial substitution of NaCl with KCl or MgCl2 is possible. Freezing affected the structure of tissue and protein properties, resulting in decreased amount of salt soluble proteins.  相似文献   
43.
Ekroos  Johan  Tiainen  Juha  Seimola  Tuomas  Herzon  Irina 《Landscape Ecology》2019,34(2):389-402
Context

The current Common Agricultural Policy (CAP) of the European Union includes three greening measures, which are partly intended to benefit farmland biodiversity. However, the relative biodiversity effects of the greening measures, including joint effects of landscape context, are not well understood.

Objectives

We studied the effects of increasing crop diversity, proportions of production grasslands and fallows, corresponding to CAP greening measures, on open farmland bird diversity, whilst controlling for the effects of distance to forests, field edge density and proportion of built-up areas.

Methods

We surveyed open farmland birds using territory mapping in Southern Finland. We modelled effects of greening measures and landscape structure on farmland birds (7642 territories) using generalised linear mixed models.

Results

Increasing proportions of grasslands increased farmland bird species richness and diversity in open farmland, whereas increasing proportions of fallows increased bird diversity. Increasing crop diversity benefited individual species, but not species richness or diversity. Increasing field edge densities consistently increased the species richness of all farmland species, in-field nesters and non-crop nesters, as well as total farmland bird diversity. The relative effect of edge density was much stronger compared to the three greening measures.

Conclusions

Our results show that promoting fallows and grasslands, in particular grazed grasslands and various types of semi-natural grasslands, has the highest potential to benefit farmland bird diversity. Maintaining or increasing field edge densities, currently not supported, seems to be of even more benefit. In open farmland, with little or no field edges, fallows and grasslands are particularly beneficial.

  相似文献   
44.
Vitamin D synthesis under solar UV-B radiation (280–315 nm) occurs widely in nature being an inherent characteristic of mammals and plants. Current data suggest that pro-Vitamin D can act as an UV-B receptor in plants, and thus monitoring the Vitamin D synthetic capacity of sunlight should be the subject of UV-B dosimetry. With this aim ‘D-dosimeter’ based on an in vitro model of Vitamin D synthesis has been designed for direct monitoring the Vitamin D synthetic capacity of sunlight in situ. Besides, ‘D-dosimeter’ possesses spectral selectivity that is helpful for detecting mid-latitude UV-B trends which accuracy is hindered by variations of solar UV radiation by clouds and aerosols, that have a comparable effect on UV-B caused by variations in stratospheric ozone.  相似文献   
45.
The cloning of equids was achieved in 2003, several years after the birth of Dolly the sheep and also after the cloning of numerous other laboratory and farm animal species. The delay was because of the limited development in the horse of more classical-assisted reproductive techniques required for successful cloning, such as oocyte maturation and in vitro embryo production. When these technologies were developed, the application of cloning also became possible and cloned horse offspring were obtained. This review summarizes the main technical procedures that are required for cloning equids and the present status of this technique. The first step is competent oocyte maturation, this is followed by oocyte enucleation and reconstruction, using either zona-enclosed or zona-free oocytes, by efficient activation to allow high cleavage rates and finally by a suitable in vitro embryo culture technique. Cloning of the first equid, a mule, was achieved using an in vivo -matured oocytes and immediate transfer of the reconstructed embryo, i.e. at the one cell stage, to the recipient oviduct. In contrast, the first horse offspring was obtained using a complete in vitro procedure from oocyte maturation to embryo culture to the blastocyst stage, followed by non-surgical transfer. Later studies on equine cloning report high efficiency relative to that for other species. Cloned equid offspring reported to date appear to be normal and those that have reached puberty have been confirmed to be fertile. In summary, horse cloning is now a reproducible technique that offers the opportunity to preserve valuable genetics and notably to generate copies of castrated champions and therefore, offspring from those champions that would be impossible to obtain otherwise.  相似文献   
46.
47.
Malus orientalis Uglitzk. is the predominant Malus species of the Caucasian forests distributed in the north of Anatolia, Armenia, Russia as well as in Iran. It is considered as one of the probable minor ancestors of domestic apples. Although M. orientalis has a lower diversity of fruit quality, other valuable traits such as later blooming, adaptation to a wider array of habitats, and capacity for longer storage of the apples should be taken into account for improving the genetic makeup of the domestic apple. A joint expedition of scientists of the Julius Kühn-Institute from Germany and the Nikolaj I. Vavilov Research Institute of Plant Industry from Russia was performed into the North Caucasus region during August/September 2011. Altogether 101 M. orientalis accessions were collected from eight sites at the North Caucasus. Twenty-six traits such as size, color, shape, flavor and firmness of fruit and tree habit were used for phenotypic evaluation of the accessions. A high phenotypic diversity within the collected material of M. orientalis was indicated. Accessions characterized by suitable fruit traits like bigger size, larger cover color, less bitterness and better firmness as well as more sweetness and better flavor were found. However, small-sized flavorless fruits were also detected. Tree habit varied widely from upright to weeping. Subsequently, a comprehensive phenotypic and genetic evaluation of M. orientalis increases the knowledge of diversity, may provide new resources of agronomically important traits for breeding purposes, and gives support to determine accessions for a core collection.  相似文献   
48.
6-Bromohypaphorine (6-BHP) has been isolated from the marine sponges Pachymatisma johnstoni, Aplysina sp., and the tunicate Aplidium conicum, but data on its biological activity were not available. For the nudibranch mollusk Hermissenda crassicornis no endogenous compounds were known, and here we describe the isolation of 6-BHP from this mollusk and its effects on different nicotinic acetylcholine receptors (nAChR). Two-electrode voltage-clamp experiments on the chimeric α7 nAChR (built of chicken α7 ligand-binding and glycine receptor transmembrane domains) or on rat α4β2 nAChR expressed in Xenopus oocytes revealed no action of 6-BHP. However, in radioligand analysis, 6-BHP competed with radioiodinated α-bungarotoxin for binding to human α7 nAChR expressed in GH4C1 cells (IC50 23 ± 1 μM), but showed no competition on muscle-type nAChR from Torpedo californica. In Ca2+-imaging experiments on the human α7 nAChR expressed in the Neuro2a cells, 6-BHP in the presence of PNU120596 behaved as an agonist (EC50 ~80 μM). To the best of our knowledge, 6-BHP is the first low-molecular weight compound from marine source which is an agonist of the nAChR subtype. This may have physiological importance because H. crassicornis, with its simple and tractable nervous system, is a convenient model system for studying the learning and memory processes.  相似文献   
49.
A set of fluorophenoxyanilides, designed to be simplified analogues of previously reported ω-conotoxin GVIA mimetics, were prepared and tested for N-type calcium channel inhibition in a SH-SY5Y neuroblastoma FLIPR assay. N-type or Cav2.2 channel is a validated target for the treatment of refractory chronic pain. Despite being significantly less complex than the originally designed mimetics, up to a seven-fold improvement in activity was observed.  相似文献   
50.
An effective bacteriocin was identified and characterized. Lactic acid bacteria were screened against Campylobacter jejuni. One bacteriocin producer, Enterococcus faecium (NRRL B-30746), was studied. The isolate was grown, and the bacteriocin was purified to single-band homogeneity. Biochemical traits indicated that the peptide was a Class IIa bacteriocin, and it was named E 50-52. The bacteriocin had a molecular weight of 3339.7 and an isoelectric point of 8.0. The minimal inhibitory concentrations of E 50-52 against C. jejuni, Yersinia spp., Salmonella spp., Escherichia coli O157:H7, Shigella dysenteriae, Morganella morganii, Staphylococcus spp., and Listeria spp. ranged from 0.025 to 32 microg/mL. In therapeutic broiler trials, oral treatment with E 50-52 reduced both C. jejuni and Salmonella enteritidis by more than 100,000-fold in the ceca, and systemic S. enteritidis was reduced in the liver and spleen. The wide range of antibacterial activity of bacteriocin E 50-52 against pathogens provides a promising alternative to antibiotics.  相似文献   
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