495 research outputs found
Suvremeni putokazi razvitka industrije cijevi
First the paper presents a review of steel production of the tubes in world: possible potencial is about 110 × 106 the tons (35 × 106 seamless tubes, rest welding tubes). In 2007. y. was record volume of 88,6 ×106 tons in world; 6,5% of total production of steel in world. Ratio-weldeds tubes: seamless tubes 70:30%. Further in the article are presented urgent the problems of the pipe and tube industry.Prvi dio članka daje pregled proizvodnje čeličnih cijevi u svijetu: moguća je proizvodnost 110 × 106 tona (35 × 106 tona bešavnih cijevi, ostatak šavne cijevi). U 2007. god. bila je rekordna proizvodnja cijevi u svijetu 88,6 × 106 tona, tj. 6,5% od ukupne proizvodnje čelika u svijetu. Odnos – šavne cijevi: bešavne cijevi 70:30%. U nastavku članka su navedeni žurni problemi u industriji cijevi
Effects of microclimatic variables on the onset of symptoms and signs of Moniliophthora roreri for three cacao clones in a range of incomplete resistance
Moniliophthora Pod Rot (MPR), caused by the fungus Moniliophthora roreri (Cif.) Evans et al is one of the main limiting factors of production in Latin America. Combating MPR is difficult due to the time-consuming and high cost recommended practices. This limitation is due to the current insufficient information on the biology and epidemiology of the pathogen. This research aims to compare MPR development, symptoms onset of the disease and fungal sporulation for three cacao clones in a range of incomplete resistance Pound-7 (highly susceptible), CC-137 (moderately resistant) and CATIE-R4 (highly resistant) and understand the influence of different microclimatic variables on this development. A total of 10,054 pods of 5-10 cm length were labelled during 55 weeks. Pods were observed throughout their lifetime: healthy, diseased with no sporulation, diseased with sporulating lesions, harvested. Incidence curves were built for all of the 55 generations of pods observed. Generations with nonconventional clonal behavior were selected in order to illustrate our hypothesis that environment, especially climate, could affect cacao s incomplete resistance to MPR. Differences in resistance among these clones lie in the number of resistant genes accumulated; however, the resistance of the three may be affected under certain environmental condition. Then, using GLMM, GLM and AIC surfaces we determined the specific period (when and for how long) where each microclimatic variable better explained the disease development. These new variables were combined in a complete GLMM and GLM, where only significant variables were retained. Water-related variables and temperature determine the symptoms expression for the susceptible clones, while, for the resistant clone CATIE-R4, only temperature showed up as explicative variable due to low numbers of CATIE-R4 pods showing symptoms. According to our models, there are two important events where resistance strategies could be developed for the cacao resistance strategy: fungal germination and penetration, where PAMP-triggered immunity (PTI) could be activated; and the symptoms onset, where the effector-triggered immunity (ETI) could occur. Success of these two events responds to the effect of humidity and temperature, respectively. We considered that none of the clones presents PTI as a defense mechanism against spore germination and penetration. Host resistance mechanisms resulting from the ETI are triggered internally and against colonization, where temperatures influence the success of these strategies. CATIE-R4 resistance strategy consists of the interruption of fungal colonization as an ETI strategy. This interruption also avoids fungal reproduction since the fungus has difficulties sporulating over CATIE-R4 pods, causing inoculum suppression. (Résumé d'auteur
Towards the understanding of the cocoa transcriptome: Production and analysis of an exhaustive dataset of ESTs of Theobroma cacao L. generated from various tissues and under various conditions
Theobroma cacao L., is a tree originated from the tropical rainforest of South America. It is one of the major cash crops for many tropical countries. T. cacao is mainly produced on smallholdings, providing resources for 14 million farmers. Disease resistance and T. cacao quality improvement are two important challenges for all actors of cocoa and chocolate production. T. cacao is seriously affected by pests and fungal diseases, responsible for more than 40% yield losses and quality improvement, nutritional and organoleptic, is also important for consumers. An international collaboration was formed to develop an EST genomic resource database for cacao. Fifty-six cDNA libraries were constructed from different organs, different genotypes and different environmental conditions. A total of 149,650 valid EST sequences were generated corresponding to 48,594 unigenes, 12,692 contigs and 35,902 singletons. A total of 29,849 unigenes shared significant homology with public sequences from other species. Gene Ontology (GO) annotation was applied to distribute the ESTs among the main GO categories. A specific information system (ESTtik) was constructed to process, store and manage this EST collection allowing the user to query a database. To check the representativeness of our EST collection, we looked for the genes known to be involved in two different metabolic pathways extensively studied in other plant species and important for T. cacao qualities: the flavonoid and the terpene pathways. Most of the enzymes described in other crops for these two metabolic pathways were found in our EST collection. A large collection of new genetic markers was provided by this ESTs collection. This EST collection displays a good representation of the T. cacao transcriptome, suitable for analysis of biochemical pathways based on oligonucleotide microarrays derived from these ESTs. It will provide numerous genetic markers that will allow the construction of a high density gene map of T. cacao. This EST collection represents a unique and important molecular resource for T. cacao study and improvement, facilitating the discovery of candidate genes for important T. cacao trait variation. (Résumé d'auteur
INTERACTIVE LANGUAGE STRATEGY OF THE FAMILY AS A FACTOR IN THE FORMATION OF ETHNIC TOLERANCE IN A MULTI-ETHNIC SOCIETY
The paper is devoted to the formation of an interactive language strategy in family space. The studied problem is considered in the context of the formation of ethnic tolerance. The authors prove that in modern conditions of linguistic diversity, the intense interaction between different languages, the commanding of several languages is an integral requirement and the guarantor of dialogue communication in space of various ethnic groups. Using a strategy of qualitative analysis, the authors demonstrate conclusions regarding the influence of the language strategy of the family on the formation of attitudes of ethnic tolerance
Characterization of the basal angiosperm Aristolochia fimbriata: a potential experimental system for genetic studies
BACKGROUND: Previous studies in basal angiosperms have provided insight into the diversity within the angiosperm lineage and helped to polarize analyses of flowering plant evolution. However, there is still not an experimental system for genetic studies among basal angiosperms to facilitate comparative studies and functional investigation. It would be desirable to identify a basal angiosperm experimental system that possesses many of the features found in existing plant model systems (e.g., Arabidopsis and Oryza). RESULTS: We have considered all basal angiosperm families for general characteristics important for experimental systems, including availability to the scientific community, growth habit, and membership in a large basal angiosperm group that displays a wide spectrum of phenotypic diversity. Most basal angiosperms are woody or aquatic, thus are not well-suited for large scale cultivation, and were excluded. We further investigated members of Aristolochiaceae for ease of culture, life cycle, genome size, and chromosome number. We demonstrated self-compatibility for Aristolochia elegans and A. fimbriata, and transformation with a GFP reporter construct for Saruma henryi and A. fimbriata. Furthermore, A. fimbriata was easily cultivated with a life cycle of just three months, could be regenerated in a tissue culture system, and had one of the smallest genomes among basal angiosperms. An extensive multi-tissue EST dataset was produced for A. fimbriata that includes over 3.8 million 454 sequence reads. CONCLUSIONS: Aristolochia fimbriata has numerous features that facilitate genetic studies and is suggested as a potential model system for use with a wide variety of technologies. Emerging genetic and genomic tools for A. fimbriata and closely related species can aid the investigation of floral biology, developmental genetics, biochemical pathways important in plant-insect interactions as well as human health, and various other features present in early angiosperms
Functional analysis of the theobroma cacao NPR1 gene in arabidopsis
<p>Abstract</p> <p>Background</p> <p>The <it>Arabidopsis thaliana NPR1 </it>gene encodes a transcription coactivator (NPR1) that plays a major role in the mechanisms regulating plant defense response. After pathogen infection and in response to salicylic acid (SA) accumulation, NPR1 translocates from the cytoplasm into the nucleus where it interacts with other transcription factors resulting in increased expression of over 2000 plant defense genes contributing to a pathogen resistance response.</p> <p>Results</p> <p>A putative <it>Theobroma cacao NPR1 </it>cDNA was isolated by RT-PCR using degenerate primers based on homologous sequences from <it>Brassica</it>, <it>Arabidopsis </it>and <it>Carica papaya</it>. The cDNA was used to isolate a genomic clone from <it>Theobroma cacao </it>containing a putative <it>TcNPR1 </it>gene. DNA sequencing revealed the presence of a 4.5 kb coding region containing three introns and encoding a polypeptide of 591 amino acids. The predicted TcNPR1 protein shares 55% identity and 78% similarity to <it>Arabidopsis </it>NPR1, and contains each of the highly conserved functional domains indicative of this class of transcription factors (BTB/POZ and ankyrin repeat protein-protein interaction domains and a nuclear localization sequence (NLS)). To functionally define the <it>TcNPR1 </it>gene, we transferred <it>TcNPR1 </it>into an <it>Arabidopsis npr1 </it>mutant that is highly susceptible to infection by the plant pathogen <it>Pseudomonas syringae </it>pv. tomato DC3000. Driven by the constitutive CaMV35S promoter, the cacao <it>TcNPR1 </it>gene partially complemented the <it>npr1 </it>mutation in transgenic <it>Arabidopsis </it>plants, resulting in 100 fold less bacterial growth in a leaf infection assay. Upon induction with SA, <it>TcNPR1 </it>was shown to translocate into the nucleus of leaf and root cells in a manner identical to <it>Arabidopsis </it>NPR1. Cacao NPR1 was also capable of participating in SA-JA signaling crosstalk, as evidenced by the suppression of JA responsive gene expression in <it>TcNPR1 </it>overexpressing transgenic plants.</p> <p>Conclusion</p> <p>Our data indicate that the <it>TcNPR1 </it>is a functional ortholog of <it>Arabidopsis NPR1</it>, and is likely to play a major role in defense response in cacao. This fundamental knowledge can contribute to breeding of disease resistant cacao varieties through the application of molecular markers or the use of transgenic strategies.</p
EVERYDAY PROFESSIONAL COMMUNICATIONS OF DIFFERENT GENERATIONS OF RESEARCH SCIENTISTS IN THE CONTEXT OF CLOSED RESEARCH COMMUNITIES
The paper analyzes various types of communication between older and younger generations in a research environment. Based on the participating observation and narrative interviews methods, it is shown that the personality of a scientist is largely shaped by the social environment where it is located. The conclusion is formulated that in relatively closed scientific communities, everyday communication plays an important role in the adopting the specific values of the scientific community by the younger generation of researchers, as well as their training in professional skills. As the results of the study showed, the success of professional communications is largely ensured by the value of such a characteristic as “personal equation” (a term introduced by Polanyi). In those groups, where the parameters of a "personal equation," the older and younger generations of researchers are approximately equal, the relationships are characterized as the least conflict. And, on the contrary, where there was a significant gap in the parameters of “personal equations”, community members are more likely to encounter conflict situations. That negatively affects the field of scientific socialization of the younger generation of researchers
Interdisciplinary project-based learning: technology for improving student cognition
The article studies a way of enhancing student cognition by using interdisciplinary project-based learning (IPBL) in a higher education institution. IPBL is a creative pedagogic approach allowing students of one area of specialisation to develop projects for students with different academic profiles. The application of this approach in the Ural State University of Economics resulted in a computer-assisted learning system (CALS) designed by IT students. The CALS was used in an analytical chemistry course with students majoring in Commodities Management and Expertise (‘expert’ students). To test how effective the technology was, the control and experimental groups were formed. In the control group, learning was done with traditional methods. In the experimental group, it was reinforced by IPBL. A statistical analysis of the results, with an application of Pearson χ 2 test, showed that the cognitive levels in both IT and ‘expert’ experimental groups improved as compared with the control groups. The findings demonstrated that IPBL can significantly enhance learning. It can be implemented in any institution of higher or secondary education that promotes learning, including the CALS development and its use for solving problems in different subject areas
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