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Inheritance and segregation at five microsatellite loci were studied in diploid gynogenetic and triploid backcross progenies obtained from koi × goldfish hybrid females, which produce diploid eggs. Gynogenetic and backcross progenies were obtained from three individual hybrid females by inseminating eggs with genetically inactivated and intact sperm of parental species respectively; no shock treatments were applied to the early embryos. Complete absence of paternally specific alleles at all investigated microsatellite loci has proven successful genetic inactivation of spermatozoa by irradiation and confirmed gynogenetic origin of progenies. Genotypic segregations at microsatellite loci showed almost complete homogeneity of gynogenetic progenies and their identity to female parents. These results correspond with previous cytogenetic data on the occurrence of premeiotic endomitosis in hybrid females producing diploid eggs. Fish from triploid backcross progenies had genotypes resulting from combination of entire diploid female genome and haploid genome from male.  相似文献   
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Plants and animals independently evolved the ability to recognize flagellin (also called FliC), the building block of the bacterial flagellum, as part of their innate immune response. While animals recognize a relatively large region of FliC, most plants recognize one or two short epitopes of FliC: flg22 and flgII-28. However, since most research in plants has focused on flg22 and flgII-28 and not the actual FliC protein, the importance of any FliC region beyond the two epitopes in plant immunity is poorly understood. Here we report cloning, overexpression, and purification of a Pseudomonas syringae FliC fragment from amino acid 1 to 143, which includes both FliC epitopes and the adjacent alpha helices. Exposing Arabidopsis thaliana leaves to FliC1–143 did not reveal any additional FliC recognition capabilities beyond flg22. However, while the kiwifruit species Actinidia arguta did not respond to either flg22 or flgII-28, treatment of A. arguta leaves with FliC1–143 triggered a significant reactive oxygen response, indicating recognition. This result suggests that in some plant species, recognition of FliC requires regions of FliC beyond the two well-known epitopes and that FliC1–143 represents a useful tool in the study of plant immunity.  相似文献   
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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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An experiment was conducted at Mizoram University, Aizawl, India during 2015-2017 to study the effect of integrated nutrient management on yield and quality of lemon cv. ‘Assam lemon’ (Citrus limon Burm.). The experiment was comprised of nine treatments viz. T1: 100% recommended dose of fertilizers (RDF) through inorganic fertilizers (IF); T2: 100% N through Farm Yard Manure (FYM); T3: 75% N through FYM + 25% through IF; T4: 50% N through FYM + 50% through IF; T5:75% N through FYM +25% through IF + Azotobacter + phosphate solubilizing bacteria (PSB)+ potash solubilizing bacteria (KSB); T6: 50% N through FYM + 50% through IF+ Azotobacter + PSB?+?KSB; T7: 75% N through FYM + 25% through IF?+?Azospirillum + AMF?+?KSB; T8: 50% N through FYM + 50% through IF+ Azospirillum + arbuscular mychorrhizal fungi (AMF) + KSB; T9: control. Among all treatments, T5 recorded highest value with respect to growth, yield and soil quality. While, T7 showed superiority in quality characters.  相似文献   
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Svechkina  Alina  Portnov  Boris A.  Trop  Tamar 《Landscape Ecology》2020,35(8):1725-1742
Context

Artificial light at night (ALAN) provides an array of important benefits but might also adversely affect humans and other living organisms. Yet, the existing reviews of accumulated knowledge about the multifaceted effects associated with exposure to ALAN focus on distinct ecosystem components. As a result, our understanding of potential system-wide impacts of ALAN exposure is insufficient.

Objectives

This paper attempts to bridge this knowledge gap by reviewing a wide range of studies, with a particular focus on identifying the impacts of ALAN exposure that are common to different species.

Methods

The survey is conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and covers peer-reviewed articles published from 2000 to 2019.

Results

Seventy-four eligible articles, out of 1223 initially identified, were selected and synthesized. 20% of them focus on humans, while the rest explore other living organisms, such as vertebrates, avian species, arthropods, aquatic organisms, and vegetation. The review demonstrates that similar adverse effects of ALAN exposure, ranging from sleep disturbance, depression, weight gain, eating and movement disorders, to elevated risk of cancer, are manifested across different components of the ecosystem, and therefore entail wider and more complex risks to its stability and integrity.

Conclusion

To reduce ecosystem risks, associated with constantly increasing ALAN levels, illumination policies should be based on directional and reduced nighttime lighting, which can help to avoid unnecessary exposures. The study highlights knowledge gaps that warrant further research attention.

  相似文献   
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The success or failure of an investment project in fruit production also depends on the selection of the fruit species and variety. When selecting the variety for the creation of a new orchard it is necessary to perform the synthesis of different data and to look at all aspects of the investment. This paper presents the application of DEX multi-criteria decision making. The model was applied on 7 varieties of plum from the western Balkans region that were assessed by experts from “The association of agricultural economists of Western Balkans” using the Delphi method.By applying this model it has been shown that the ’Stanley’ is the most suitable for starting a new orchard while the varieties ’?a?anska ljepotica’ and ’?a?anska rodna’ are also very suitable for starting new fruit orchards and they have also received the value attribute “very acceptable”.Using this model all strong and weak sides of the observed plum variety were shown. For the final selection it is necessary to conduct research at a specific micro location where all characteristics of that area would also be taken into consideration.  相似文献   
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