936 resultados para germplasm collection


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Low temperatures at the initial stages of rice development prevent fast germination and seedling establishment and may cause significant productivity losses. In order to develop rice cultivars exhibiting cold tolerance, it is necessary to investigate genetic resources, providing basic knowledge to allow the introduction of genes involved in low temperature germination ability from accessions into elite cultivars. Japanese rice accessions were evaluated at the germination under two conditions: 13 degrees C for 28 days (cold stress) and 28 degrees C for seven days (optimal temperature). The traits studied were coleoptile and radicle length under optimal temperature, coleoptile and radicle length under cold and percentage of the reduction in coleptile and radicle length due to low temperature. Among the accessions studied, genetic variation for traits related to germination under low temperatures was observed and accessions exhibiting adequate performance for all investigated traits were identified. The use of multivariate analysis allowed the identification of the genotypes displaying cold tolerance by smaller reductions in coleoptile and radicle lenght in the presence of cold and high vigour, by higher coleoptile and radicle growth under cold.

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The objective of this study was to evaluate the genetic differences among three matrix groups of Cedrela fissilis based on quantitative juvenile variables on a progeny test to define seed collecting zones and use of seeds of this species in the study region as well as to evaluate genetic variability of the sampled material. A progeny test was established in a nursery with seeds from 48 seed trees collected in the municipalities of Rio Negrinho, Mafra and Sao Bento do Sul, state of Santa Catarina, and in the municipalities of Lapa, Rio Negro, Campo do Tenente and Antonio Olinto, state of Parana. Of the collected seed trees, 33 sampled trees were distributed in three sites and 15 trees were dispersed in the studied region. It was used a complete random block design, with 8 replicates and 20 plants per plot. Evaluated data included: emergency rate; seedling base diameter and height (61, 102 and 145 days after the seeds were sowed); seedling survival; number of leaves per seedling; aerial section dry mass and root dry mass; and the foliar area of the third fully expanded leaf measured from the apical meristem. The Maximum Restricted Likelihood Method (REML) was used, using the software SELEGEN for analysis. It was found that the juvenile characters are strongly genetically controlled and they can be used to estimate genetic variability of population samples of Cedrela fissilis. The three groups of trees spatially limited did not significantly differ among each other, allowing to conclude that the three areas are part of the same tree seed transfer zone.

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The Diptera collection of the Natural History Museum Berlin holds one of the most important collections of Neriidae. In this paper, the type specimens (holotypes, lectotypes, paratypes, paralectotypes, syntypes) of this historical collection are listed. 28 species-group taxa are dealt with. A lectotype designation is made for the species Brachantichir purpusianus Enderlein, 1922 in order to fix the identity of the name. Holotypes are recognized by monotypy of the species Chaetomeristes bullatus Enderlein, 1922; Chaetomeristes peruanus Enderlein, 1922; Derocephalus angusticollis Enderlein, 1922; Glyphidops limbatus Enderlein, 1922; Longina abdominalis Wiedemann, 1830; Loxozus clavicornis Enderlein, 1922; Oncopsia mexicana Enderlein, 1922; Paranerius fibulatus Enderlein, 1922; Telostylinus dahli Enderlein, 1922; Telostylus latibrachium Enderlein, 1922; and Telostylinus luridus Enderlein, 1922. Syntypes are labelled and listed for Brachantichir robusta Enderlein, 1922; Nerius terebratus Enderlein, 1922; Odontoloxozus punctulatus Enderlein, 1922; Telostylinus apicalis Enderlein, 1922; Telostylinus obscuratus Enderlein, 1922; and Telostylinus ornatipennis Enderlein, 1922. The account concludes with geographic and taxonomic summaries; an appendix listing the abbreviations, localities, and collectors cited in the text; and a bibliography. ((c) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

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The ornamental market is dynamic and demands constant novelties. The use of fruit crops as ornamental plants can be an interesting alternative with very differentiated and original products. The banana germplasm bank at Embrapa Cassava and Fruits has been primarily used in the breeding program for generating new cultivars as food. To diversify and expand the use of this collection, accessions with ornamental potential have been selected to obtain new hybrids. This work was aimed at characterizing the progeny of ornamental Musa L. spp. by grouping the hybrids according to the following uses: landscape plants, potted plants, cut flower, or minifruits. Forty-two hybrids were evaluated with 14 quantitative and 12 qualitative descriptors in three production cycles. In addition, assays for resistance to black and yellow Sigatoka and to Fusarium wilt were performed. Variability was observed for all the characteristics evaluated within progenies, especially with regard to leaf color, fruit, peduncle, rachis, and heart. All evaluated hybrids were resistant to yellow Sigatoka and to Fusarium wilt and were resistant or showed reduced symptoms of susceptibility to black Sigatoka. Most hybrids (82%) presented reduced plant height. After clustering by use category, the hybrids RM 09, RM 38, RM 37, and RM 33 were selected and recommended to be used as cut flowers, minifruits, or landscaping plants.

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Background: The CUPID (Cultural and Psychosocial Influences on Disability) study was established to explore the hypothesis that common musculoskeletal disorders (MSDs) and associated disability are importantly influenced by culturally determined health beliefs and expectations. This paper describes the methods of data collection and various characteristics of the study sample. Methods/Principal Findings: A standardised questionnaire covering musculoskeletal symptoms, disability and potential risk factors, was used to collect information from 47 samples of nurses, office workers, and other (mostly manual) workers in 18 countries from six continents. In addition, local investigators provided data on economic aspects of employment for each occupational group. Participation exceeded 80% in 33 of the 47 occupational groups, and after pre-specified exclusions, analysis was based on 12,426 subjects (92 to 1018 per occupational group). As expected, there was high usage of computer keyboards by office workers, while nurses had the highest prevalence of heavy manual lifting in all but one country. There was substantial heterogeneity between occupational groups in economic and psychosocial aspects of work; three-to fivefold variation in awareness of someone outside work with musculoskeletal pain; and more than ten-fold variation in the prevalence of adverse health beliefs about back and arm pain, and in awareness of terms such as "repetitive strain injury" (RSI). Conclusions/Significance: The large differences in psychosocial risk factors (including knowledge and beliefs about MSDs) between occupational groups should allow the study hypothesis to be addressed effectively.

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An annotated list is provided of the type specimens of seven species of Bolitophilidae Winnertz, 1863 and Ditomyiidae Keilin, 1919 (Diptera, Bibionomorpha) the Museum national d' Histoire naturelle (Paris).

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Models of the filtration phenomenon describe the mass balance in bed filtration in terms of particle removal mechanisms, and allow for the determination of global particle removal efficiencies. These models are defined in terms of the geometry and characteristic elements of granule collectors, particles and fluid, and also the composition of the balance of forces that act in the particle collector system. This work analyzes particles collection efficiency comparing downflow and upflow direct filtration, taking into account the contribution of the gravitational factor of the settling removal efficiency in future proposal of initial collection efficiency models for upflow filtration. A qualitative analysis is also made of the proposal for the collection efficiency models for particle removal in direct downflow and upflow filtration using a Computational Fluid Dynamics (CFD) tool. This analysis showed a strong influence of gravitational factor in initial collection efficiency (t = 0) of particles, as well as the reasons of their values to be smaller for upflow filtration in comparison with the downflow filtration.

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[ES] Esta tesis trata sobre los prólogos a textos ingleses de carácter médico escritos o copiados en forma de prosa durante el siglo XV. En este trabajo se han contemplado dos objetivos generales: por un lado, la creación de un corpus con todos los prólogos inéditos que cumplen con estos criterios y que se encuentran en la colección de Sloana en la British Library de Londres, según Voigts & Kurtz: Scientific an Medical Writtings in Old and Middle English: An Electronic Reference (2000); y por otro, la presentación de estod prólogos como conjunto, incluyendo: los datos recopilados sobre la codicología de los manuscritos, afiliación de los textos, sus fuentes y el dialecto utilizado. Asimismo, como parte de esta presentación, se aporta un análisis original de la estructura, forma y contenido de los materiales seleccionados para el estudio. El propósito de esta tesis es llenar un hueco en la literatura académica acerca de los prólogos a textos médicos escritos en inglés medieval tardío, tal y como lo señala Voigts (1982:54)

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Entheses (skeletal attachment sites of muscles and ligaments) and their pathologic modifications (enthesopathies) have long been used as skeletal markers of activity in bioarchaeological (reconstruction of past populations lifestyle) and forensic (personal identification) contexts. However, a functional interpretation of these markers have to deal critically with the multifactorial etiology of the same. Factors such as sex, age, genetic factors, mechanical stress, metabolic conditions, etc.. can compete to produce the observed morphological variability at each attachment site. The aim of this thesis has drawn on the ongoing debate about the informativeness of entheseal modifications as skeletal markers of activity and represent a deepening of the actual knowledge about the relationship between these characters and sex, age and physical activity. For this purpose, the whole "Frassetto” identified skeletal collection of Sassari (Sardinia, Italy) was analyzed. The collection includes the skeletal remains of about 600 individuals died in the late 19th and early 20th century for whom information regarding sex, age at death and, in many cases the occupation are known The results obtained highlight the great age importance on the entheseal modifications. The differences observed between sexes may reflect differences in the level or type of activity performed in life, but could also be related to a different bone tissue response to mechanical stress due to hormonal factors and different growth rates. The role of biomechanical stress related to professional activities remains doubtful. This is probably partly attributable to the analyzed sample characteristics (preponderance of farmers compared with other professions, different mean age of the considered professional subsamples), which has hampered the analysis of samples homogenous with regard to age, which is very influential on the entheses and enthesopathies expression.

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Osteoarthritis (OA) or degenerative joint disease (DJD) is a pathology which affects the synovial joints and characterised by a focal loss of articular cartilage and subsequent bony reaction of the subcondral and marginal bone. Its etiology is best explained by a multifactorial model including: age, sex, genetic and systemic factors, other predisposing diseases and functional stress. In this study the results of the investigation of a modern identified skeletal collection will be presented. In particular, we will focus on the relationship between the presence of OA at various joints. The joint modifications have been analysed using a new methodology that allows the scoring of different degrees of expression of the features considered. Materials and Methods The sample examined comes from the Sassari identified skeletal collection (part of “Frassetto collections”). The individuals were born between 1828 and 1916 and died between 1918 and 1932. Information about sex and age is known for all the individuals. The occupation is known for 173 males and 125 females. Data concerning the occupation of the individuals indicate a preindustrial and rural society. OA has been diagnosed when eburnation (EB) or loss of morphology (LM) were present, or when at least two of the following: marginal lipping (ML), esostosis (EX) or erosion (ER), were present. For each articular surface affected a “mean score” was calculated, reflecting the “severity” of the alterations. A further “score” was calculated for each joint. In the analysis sexes and age classes were always kept separate. For the statistical analyses non parametric test were used. Results The results show there is an increase of OA with age in all the joints analyzed and in particular around 50 years and 60 years. The shoulder, the hip and the knee are the joints mainly affected with ageing while the ankle is the less affected; the correlation values confirm this result. The lesion which show the major correlation with age is the ML. In our sample males are more frequently and more severely affected by OA than females, particularly at the superior limbs, while hip and knee are similarly affected in the two sexes. Lateralization shows some positive results in particular in the right shoulder of males and in various articular surfaces especially of the superior limb of both males and females; articular surfaces and joints are quite always lateralized to the right. Occupational analyses did not show remarkable results probably because of the homogeneity of the sample; males although performing different activities are quite all employed in stressful works. No highest prevalence of knee and hip OA was found in farm-workers respect to the other males. Discussion and Conclusion In this work we propose a methodology to score the different features, necessary to diagnose OA, that allows the investigation of the severity of joint degeneration. This method is easier than the one proposed by Buikstra and Ubelaker (1994), but in the same time allows a quite detailed recording of the features. Epidemiological results can be interpreted quite simply and they are in accordance with other studies; more difficult is the interpretation of the occupational results because many questions concerning the activities performed by the individuals of the collection during their lifespan cannot be solved. Because of this, caution is suggested in the interpretation of bioarcheological specimens. With this work we hope to contribute to the discussion on the puzzling problem of the etiology of OA. The possibility of studying identified skeletons will add important data to the description of osseous features of OA, enriching the medical documentation, based on different criteria. Even if we are aware that the clinical diagnosis is different from the palaeopathological one we think our work will be useful in clarifying some epidemiological as well as pathological aspects of OA.

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This paper aims to show, analyze and solve the problems related to the translation of the book with meaning-bond alphabetically ordered chapter titles La vita non è in ordine alfabetico, by the Italian writer Andrea Bajani. The procedure is inevitable for a possible translation of the book, and it is necessary to have a preliminary pattern to follow. After translating the whole book, not only is a revision fundamental, but a restructure and reorganization of the collection may be required, hence, what this thesis offers is a scheme to start from, together with an analysis of the possible problems that may arise, and a useful method to find a solution.