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991.
Teodora Popova Stanislava Grozeva Velichka Todorova Gergana Stankova Nikolay Anachkov Velichka Rodeva 《Acta Physiologiae Plantarum》2016,38(11):273
Anther culture is one of the most important and useful tool to create pure lines for plant breeding programs rapidly. Some pepper genotypes are recalcitrant and embryogenic frequency in anther culture is still low or reaction is not observed at all. Temperature stress (low or high) can facilitate switching the microspore to sporophyte developmental pathway. In this study, some differences were found in embryogenic reaction among the pepper genotypes and culture media variants, depending on duration of cold treatment of flower buds. Experimental results indicated that embryogenic efficiency decreased under low-temperature stress. Nevertheless, positive effect of cold pretreatment on direct embryo induction was obtained in four genotypes—cultivar Hebar, hybrid 50/01 and lines 668/02 and 1312/02. Increasing of embryogenic reaction after cold pretreatment was observed in media variants C (24 h) and MS-3 + (24 and 48 h), while on medium variant C-0 direct embryo formation was registered only after 48 h cold pretreatment. These results show that the donor genotypes have specific requirements for type and duration of temperature pretreatment and also culture media for induction of androgenesis with higher frequency. 相似文献
992.
993.
Lauren Carruth 《Culture, medicine and psychiatry》2016,40(2):181-197
Drawing on ethnographic research with Somalis, within aid organizations, and within health care facilities in the Somali Region of Ethiopia, this article argues that what is called “global health diplomacy,” despite its origins and articulations in interstate politics, is fundamentally local and interpersonal. As evidence, I outline two very different health programs in the Somali Region of Ethiopia, and how, in each, existing animosities and political grievances were either reinforced or undermined. I argue that the provision of health care in politically insecure and post-conflict settings like the Somali Region of Ethiopia is precarious but pivotal: medical encounters have the potential to either worsen the conditions in which conflicts and crises recur, or build new interpersonal and governmental relations of trust. Effective global health diplomacy, therefore, cannot be limited to building clinics and donating medicine, but must also explicitly include building positive relationships of trust between oppositional groups within clinical spaces. 相似文献
994.
Sara Cooper 《Culture, medicine and psychiatry》2016,40(3):307-337
A strong movement has emerged recently which is highlighting the high levels of untreated mental illness in Africa and making proposals for reducing this ‘gap’ in mental health care. This movement has been criticised for insufficiently attending to the epistemologies embedded in its recommendations, and inadequately considering the views of practitioners ‘on the ground’. Employing a narrative-based approach, I accessed the stories about the mental health ‘treatment gap’ of 28 psychiatrists all working clinically in public mental health care settings in South Africa, Uganda, Nigeria or Ethiopia. Rather than focusing on the content of these stories, I was more interested in their underpinning meaning-codes and epistemological politics. Dominant thinking about the ‘treatment gap’ was heavily informed by a biomedical paradigm, and associated epistemological order of European Colonial Modernity. There were, however, cracks in this master narrative, which crystalised in the stories that were told by three particular psychiatrists. Their narratives operated within an alternative paradigm, one which appears to be informed by the tradition of phenomenology, and in particular the ideas associated with French philosopher Merleau-Ponty. This more marginalised thinking may offer important insights into reducing the mental health ‘treatment gap’ in Africa in ways very different from those created by current seats of power. 相似文献
995.
Andrew Buskell 《Biology & philosophy》2016,31(3):435-446
Morin has written a rich and valuable book. Its main aim is to isolate the factors involved in maintaining behavioural lineages over time, and to understand how these factors might interact. In doing so, it takes issue with the abstract and idealised models and arguments of dual-inheritance theorists, which are alleged in this account to rely on an overly simplistic notion of imitative learning. Morin’s book is full of ethnographic, anthropological, and psychological research, and there is much to commend in it. However, Morin’s arguments against the dual-inheritance theorists are less convincing when put under scrutiny, and his positive picture which includes appeals to ostensive communication, intrinsic appeal and cultural attraction has some difficulties. I argue that when we contrast dual-inheritance theorists and Morin, we find that there may be fewer differences and greater commonalities than Morin’s book might suggest. 相似文献
996.
Marc Artiga 《Biology & philosophy》2016,31(4):483-505
Naturalistic theories of representation seek to specify the conditions that must be met for an entity to represent another entity. Although these approaches have been relatively successful in certain areas, such as communication theory or genetics, many doubt that they can be employed to naturalize complex cognitive representations. In this essay I identify some of the difficulties for developing a teleosemantic theory of cognitive representations and provide a strategy for accommodating them: to look into models of signaling in evolutionary game theory. I show how these models can be used to formulate teleosemantics and expand it in new directions. 相似文献
997.
998.
Takumi Higaki Natsumaro Kutsuna Kae Akita Hisako Takigawa-Imamura Kenji Yoshimura Takashi Miura 《PLoS computational biology》2016,12(4)
Plant leaf epidermal cells exhibit a jigsaw puzzle–like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo. 相似文献
999.
Phytoplankton community of the drinking water supply reservoir Borovitsa (South Bulgaria) with an emphasis on cyanotoxins and water quality 总被引:1,自引:0,他引:1
Ivanka Teneva Rumen Mladenov Detelina Belkinova Ivanka Dimitrova-Dyulgerova Balik Dzhambazov 《Central European Journal of Biology》2010,5(2):231-239
The phytoplankton diversity, algal biomass, and selected physicochemical parameters were investigated in the drinking water
reservoir (Borovitsa) located in the Kardzhali region, Bulgaria. Particular attention was given to Cyanoprokaryota and presence
of cyanotoxins in the water samples. Twenty-nine species belonging to six divisions (Cyanoprokaryota, Chlorophyta, Zygnemophyta,
Dinophyta, Euglenophyta and Bacillariophyta) were identified. The microscopic examination of the phytoplankton samples showed
the dominance of Ankyra judayi, Oocystis lacustris (Chlorophyta) and Aphanizomenon flos-aquae (Cyanoprokaryota) in July 2006, and Microcystis pulverea, Synechococcus elongatus (Cyanoprokaryota), Radiococcus planktonicus (Chlorophyta) and Melosira varians (Bacillariophyta) in September 2006. A blooming event due to Aphanizomenon flos-aquae was observed in July 2006. The reservoir exhibits a tendency to shift from an oligotrophic environment to a state of mesotrophy.
Presence of cyanotoxins such as anatoxin-a, microcystins and saxitoxins were analyzed by HPLC and ELISA methods. Our results demonstrated the presence of anatoxin-a
and microcystins (0.09 μg/L) in the raw water samples from July 2006, and saxitoxins (2.5 μg/L) and microcystins (0.18 μg/L)
in the raw water samples from September 2006. The study underlines that permanent monitoring programs of Cyanoprokaryota in
the reservoirs used as sources of drinking water and toxicity assessments should be implemented. Indirect exposure and transfer
of cyanotoxins through food chains must also be considered. 相似文献
1000.
Choi YS Cho ES Je YH Roh JY Chang JH Li MS Seo SJ Sohn HD Jin BR 《Current microbiology》2004,48(1):47-50
Bacillus thuringiensis 656-3, isolated from a soil sample collected at mushroom houses, showed high toxicity to mushroom flies, Lycoriella mali and Coboldia fuscipes. B. thuringiensis 656-3 produced bipyramidal inclusions and reacted with the H antiserum of B. thuringiensis subsp. morrisoni (H8a8b). The plasmid and protein profiles of B. thuringiensis 656-3 were similar to those of its reference strain, subsp. morrisoni PG-14. However, PCR analysis using cry gene primers showed that B. thuringiensis 656-3, unlike its reference strain, had cry4A, cry4B, cry10A, cry11A, and cry1Ac genes, suggesting that B. thuringiensis 656-3 was a unique strain with respect to gene type. In addition, B. thuringiensis 656-3 showed a high level of toxicity against mushroom flies, L. mali and C. fuscipes. 相似文献