Academic literature on the topic 'Shea tree'
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Journal articles on the topic "Shea tree"
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Houehanou, Thierry, Valentin Kindomihou, and Brice Sinsin. "Effectiveness of conservation areas in protecting Shea trees against hemiparasitic plants (Loranthaceae) in Benin, West Africa." Plant Ecology and Evolution 144, no. (3) (2011): 267–74. https://doi.org/10.5091/plecevo.2011.485.
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<b>Background and aims</b> – The Shea tree (<i>Vitellaria paradoxa</i>), a multi-purpose species highly valued for the oil obtained from its seeds, is commonly maintained in the semi-arid parklands in West African Sudanian zone. However, most of the trees were reported to be infested with mistletoes – plant parasites that may lead to death of the Shea tree and these parasites are known to be directly dispersed on their host by birds. This study therefore aimed to assess the potential effectiveness of protected area on preventing mistletoes proliferation on Shea tree individuals. <b>Methods</b> – Infestations in two habitats: land use area (fields and fallows) and protected area of Pendjari hunting zone were compared. Overall 54 plots of 1 ha (100 m × 100 m) with 487 and 252 individuals of Shea tree in land use and protected area respectively were investigated. ANOVA was used to compare Shea tree infestation rate and infestation degree (with regard to diameter and height of infested Shea tree). Principal Component Analysis (PCA) was performed to correlate the habitats with infestation degree. <b>Key results</b> – The results showed that about 80% of Shea tree individuals were infested in the land use area, this rate was significantly higher than the one of 27.3% observed in the protected area. Overall, heavily infested Shea trees had significantly larger trunks and heights, mainly in land use areas. The land use area was shown to be correlated with high and very high Shea tree infestation degrees while the others infestations degrees (very weak, weak and moderate) were correlated with both areas. <b>Conclusions</b> – Shea trees growing in protected areas are better protected against mistletoe plant parasites than those on cultivated land. Various hypotheses to explain this result are discussed.
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Nafan, Diarrassouba, Dago Dougba Noel, and Yao Saraka Didier Martial. "ESTIMATION OF SHEA TREES (Vitellaria paradoxa C.F. GAERTN.) FRUIT PRODUCTION BY ASSESSING THE CORRELATION BETWEEN YIELD PARAMETERS AND DENDROMETRIC FEATURES IN NORTHERN OF CÔTE D'IVOIRE." Journal of Experimental Biology and Agricultural Sciences 9, no. 6 (2021): 745–58. http://dx.doi.org/10.18006/2021.9(6).745.758.
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Vitellaria paradoxa, commonly known as the shea tree, is a tree of the family Sapotaceae and represents a traditional African food plant. It has been claimed to have the potential to improve nutrition, boost food supply, foster rural development, and support sustainable land care. Despite its multiple potentials, statistical data relating to its production are non-existent and/or unexploited in several African communities. To contrast this tendency, the present study aims to assess the intra-seasonal variation in fruit production of a sample of 115 shea trees and then to establish a correlation between yield parameters and several dendrometric features. Dendrometric (i.e. tree height, trunk girth, and crown basal area) and pomological (i.e. fruit and nut length and width) parameters, as well as yield parameters by monitoring daily fallen fruit from each sampled shea tree, carried out for five years consecutively, were considered for this study. The results showed inter-year fluctuation of shea fruit/nut number and shea fruit/nut weight. In addition, the results showed a significant increase in the annual average of shea fruit/nut yield per tree and as well per girth and/or crown basal area interval class, randomly generated by Sturge and Yule's formula. Interestingly, potentially high producing trees emerged within each considered interval class. Then, observed intraclass variation between trees determining shea yield can be exploited in selecting elite shea trees.
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Sheshi, Umar Isah. "Attitude of farmers towards domestication of shea tree cultivation in Niger State, Nigeria." Journal of the Bangladesh Agricultural University 16, no. 2 (2018): 271–75. http://dx.doi.org/10.3329/jbau.v16i2.37982.
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Despite the socio-economic potentials of shea tree and it ability to grow well in Niger State, the tree crop is yet to be domesticated in farms. Thus, the study examined the attitude of farmers towards the cultivation of shea tree in Niger State, Nigeria. To achieve the study objectives, 210 respondents were randomly selected for the study and data were collected using validated interview schedule with reliability coefficient of 0.85. The collected data were analyzed using descriptive statistics and logit regression model. Result indicated that the mean age of the respondents was 52 years. Number of shea trees owned by 50.48% of the respondents ranged from15–20 trees which mostly grow naturally. Result further revealed that the respondents had favourable attitude towards most of the issues bordering on shea trees domestication. The issues that attracted least unfavourable attitude were long gestation period and inadequate awareness on the need to plant and manage wild trees. Factors that influenced willingness to plant shea trees were sex, attitude, land ownership, educational level and marital status. Therefore, it was recommended that youths, women and married couples should be encouraged by government to go into shea trees cultivation. It was also suggested that farmers should be educated by extension agents to encourage on-farm shea tree planting culture and agroforestry initiatives.J. Bangladesh Agril. Univ. 16(2): 271-275, August 2018
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Calvin, Esagu John, Budi Warsito, Jafron Wasiq Hidayat, Akello Gertrude, Gudoyi M. Paul, and Kamil Ahmed. "Assessing the impact of Charcoal Production Activities on the Shea Nut Tree Vegetation Cover." Journal of Bioresources and Environmental Sciences 2, no. 3 (2023): 109–18. http://dx.doi.org/10.14710/jbes.2023.19260.
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Charcoal remains the main energy cooking source for urban dwellers in Uganda. The Shea Nut tree produces quality charcoal which is efficient and locally made. Therefore, it is facing increasing threats from the local communities so as to meet the mushrooming demand. The study analyses the state of the Shea Nut tree, drivers of charcoal production, predict Shea Nut tree vegetation coverage, and establish mechanisms for sustainable utilization and conservation of the Shea Nut trees in Kapelebyong District. Landsat images were classified using likelihood classification in ArcGIS and interviews were conducted whilst geospatial, Stata, and Nvivo tools were used for analysis. The findings reflect a sharp declining trend in the coverage of the shea Nut trees by 2.3% and 6% from 2002-2012 and 2012-2022 respectively. The major drivers include high demand from urban areas, the need for income, and unemployment. As a result, it is predicted that by 2032, the coverage will have reduced to only 713 hectares (7.3%) from 1277 hectares (10.6%) in 2022. Therefore, charcoal production with other land uses has greatly resulted in Shea Nut tree deterioration. The study recommends the use of alternative energy sources, the provision of alternative income-generating activities for the local communities, Government of Uganda through NFA needs to enforce the ways through which Shea Nut trees are managed and utilized in order to minimize illegal cutting.
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Ogwok, Gertrude, Sarah Kizza-Nkambwe, Junior Senyonga Kasima, Maxmillan Mpewo, and Peter O. Alele. "Soil Physical and Chemical Properties under Shea Tree (Vitellaria paradoxa) at Different Stages of Growth." East African Journal of Forestry and Agroforestry 7, no. 1 (2024): 309–18. http://dx.doi.org/10.37284/eajfa.7.1.2175.
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Shea tree (Vitellaria paradoxa), is one of the dominant agro-forestry species in Otuke district of Northern Uganda. Due to its economic importance and, in line with the numerous threats the tree is faced with, there is an urgent need for measures to conserve this species, for example, through incorporating annual food crops in the Shea tree parkland. This, however, requires a better understanding of tree-soil-food crop interactions. A number of studies of this aspect either considered only the mature Shea tree gardens or did not provide a clear distinction between the physiological states of the Shea tree. This was the motivation for this study where we compare variation in soil properties under mature and young Shea tree gardens with sites not having trees in Okwang sub-county, Otuke district. Five soil samples (up to 15 cm deep for top soil and 15-30 cm for sub-soil) were obtained per treatment using a soil auger. Our results show that in the top soil, only percent sand varied among the treatments, while, in the sub-soil, only percentage nitrogen and average phosphorus varied among the treatments. We also found that percentage top soil organic matter and percentage of sub-soil sand had negative strong correlations with maize and soybean yields, while percentage sub-soil clay had a strong positive correlation with maize and soybean yield. We conclude that variations in soil physical and chemical properties under Mature and Young Shea gardens only occur for those properties that have a direct link to tree residues
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Semde, Kadidia, Konoyaon Somda, Hadou Haro, Schémaéza Bonzi, Souleymane Ganaba, and Irénée Somda. "Identification of pathogens and monitoring methods for leaf spots disease of shea tree (Vitellaria paradoxa Gaertn. C. F.) in the cropping systems of Komki Ipala (Burkina Faso)." International Journal of Biological and Chemical Sciences 16, no. 1 (2022): 88–97. http://dx.doi.org/10.4314/ijbcs.v16i1.8.
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Vitellaria paradoxa is a multipurpose plant species which unfortunately is under multiple pressures causing damages to the plant. This study was to develop methods for monitoring causative agents of shea trees leaf spots in Burkina Faso. An inventory of shea tree individuals and a characterization of leaf spots were performed in Tampoussoumdi, Burkina Faso. Thus, twelve (12) plots of 100 m x 50 m were set up in fallows and fields for identifying all shea trees. Pathogens were also identified by isolated infected leaves fragments of on PDA medium. Isolates were purified and observed under a microscope (X40). As to develop pathogens monitoring methods, three mycorrhizal fungi (yac, fada, Ga) were used to inoculate shea trees cultivated in greenhouse. After two months, inoculated plant leaves were sprayed with prepared isolates of identified pathogens and infection occurrence was checked daily. Results revealed that infection occurred only in unburned fallows and concerned 65% of the shea tree communities. Fungi were found to be responsible for these infections and three species were identified including Fusarium moniliforme, Pestalotia guepini and Phoma sorghina. Results also showed that mycorrhizae can inhibit pathogens growth partially or totally. Their potential use could help controlling the leaf spots disease in shea parks.
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Okiror, Paul, Jacob Godfrey Agea, Clement Akais Okia, and John Bosco Lamoris Okullo. "On-Farm Management ofVitellaria paradoxaC. F. Gaertn. in Amuria District, Eastern Uganda." International Journal of Forestry Research 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/768946.
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The population of shea butter tree (Vitellaria paradoxaC. F. Gaertn.)—a priority tree with enormous economic and cultural values to the parkland communities in Uganda, is rapidly declining due to rapid human population growth, increasing land fragmentation, and high demand for woodfuel especially charcoal. Reversing this trend will depend on the rural community involvement in the planting, facilitating natural regeneration, and tending of shea trees on farm. As such a survey was conducted in Amuria district, eastern Uganda, to assess local strategies and constraints to on-farm management of shea trees, and document socio-demographic factors influencing the on-farm conservation. About 93% of the households protected naturally regeneratedV. paradoxatrees mainly on farms.V. paradoxawas mostly propagated through coppices and seedlings. Although insecure land tenure, insecurity, pests, disease, and shortage of planting materials were reported as major hindrances, farmsize, family size, and gender significantly (P≤0.05) influenced people’s willingness to conserveV. paradoxa. Byelaws and policies on shea conservation need to be properly enforced, and further propagation research is required especially towards shortening the juvenile period ofV. paradoxaso that more farmers can start propagating the tree other than relying on its natural regeneration.
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Ndagi, I., Lawal, A. F., Paiko, M. A., and Baba, K. C. "ASSESSMENT OF IMPROVED METHODS OF SHEA-NUT COLLECTION AMONG SHEA-NUT PICKERS IN NIGER STATE." Journal of Agripreneurship and Sustainable Development 7, no. 2 (2024): 93–97. http://dx.doi.org/10.59331/jasd.v7i2.752.
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The study examine the assessment of improved methods of Shea-Nut collection among Shea-Nut pickers in Niger State. Data were collected with the aid of well-structured questionnaire and focus group discussions, analyzed using descriptive statistics such as frequency distribution, mean and standard deviation. A multi- stage sampling technique was used to select a total of the 200 respondents for the study. The result revealed that the 41.50% of the respondents were within age bracket of 31-40 years. However, 92.5% of the sampled respondents were married with non-formal education. In addition, 53.50% of the respondents earn N50,000.00 as income. Majority (89.00%) of the respondents collect the shear-nut in an opened field. From the estimate of the regression, educational level was significant factor (p<0.05) in determining shea nut collection method. The study concluded that, Shea nut collectors are mainly women, aged and married, with non-formal education. The choice of collection techniques are influenced by occupation and the educational status of the respondents. It is recommended that stakeholders in Shea-nut industry should interact with Nigerian Institute for Oil palm Research (NIFOR) that has the national mandate on Shea tree research and development to produce sufficient quantity of hybrid/improved Shea tree seedling varieties for modern plantation establishments.
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Diarassouba, Nafan, Kouablan E. Koffi, Kanga A. N'Guessan, Patrick Van Damme, and Abdourahamane Sangare. "Connaissances locales et leur utilization dans la gestion des parcs à karaté en Côte d’Ivoire." Afrika Focus 21, no. 1 (2008): 77–96. http://dx.doi.org/10.1163/2031356x-02101007.
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In order to assess both the level of botanical knowledge of the shea tree species possessed by certain communities, and the relative importance of the species to those communities, an inventory has been taken of the different uses of shea resources. To this end, research was conducted involving 257 people belonging to 12 different ethnic groups in seven departments of the north of the Cote d'Ivoire [Ivory Coast]. The results of these investigations clearly demonstrate the socioeconomic importance of shea trees to the local populations of the zone investigated. Some ethnic groups prove to have a very good botanical knowledge of the species and its qualities and have developed systems of management of shea orchards that could facilitate the domestication and conservation of the species. In addition to the commercial use of the kernel and of shea butter on local and regional markets, many other parts of the shea tree and derived products (roots, leaves, peels, oilcakes, latexes and even mistletoes are used for a range of different purposes by rural communities in Cote d’Ivoire [the Ivory Coast]. In medicine and in traditional pharmacopeia, these parts are used in the treatment of several diseases. Shea is also valued at the cultural, nutritional, agricultural, cosmetic, artisanal level.
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Konan, Alphonse Alui, Diarrassouba Nafan, and Didier Martial Yao Saraka. "Carbon Sequestration Potential of Shea Trees (Vitellaria paradoxa C.F. Gaertn.) in Parklands under Two Soil Types (Ferralsol and Cambisol) in Northern Côte d'Ivoire." International Journal of Sciences Volume 9, no. 2020-02 (2020): 14–23. https://doi.org/10.5281/zenodo.3980043.
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This study was conducted to assess carbon sequestration potential of shea trees in four shea parks in Northern Côte d'Ivoire to fight against climate change. The methodology used consisted in the delimitation of 2 ha of plot in shea parkland located in Ferkéssédougou, Ouangolodougou, Boundiali and Tengrela. On each plot delimited within these parklands, forests inventories were carried out and stem diameter at 1.30 m aboveground (DBH ≥ 5 cm) of the shea trees were measured. The dendrometric data collected made it possible to elaborate the structure of the shea trees in parkland, to estimate the biomass and the stocks of sequestered carbon. The results showed that shea populations, irrespective of the study site, showed a "reversed J" diameter distribution with decreasing individuals. The spatial distribution of the population of shea trees in Boundiali and Ferkéssédougou parklands is regular while it is aggregative in Ouangolodougou and Tengrela parklands. The spatial distribution of shea trees depends on the type of soils. Of all the sites that are mostly bushy savannas, sequestered CO2 equivalents are high: 70.83 t.ha-1 at Boundiali, 49.47 t.ha-1 at Ferkéssédougou, 215 t.ha-1 at Ouangolodougou and 130 t.ha-1 at Tengrela. This study shows that agroforestry is to be promoted in Northern Côte d'Ivoire through the protection of shea tree parklands that limit greenhouse gas emissions in the atmosphere, especially in Northern Côte d'Ivoire. This will certainly facilitate Côte d'Ivoire's access to the carbon market.Read Complete Article at ijSciences: V92020012265 AND DOI: http://dx.doi.org/10.18483/ijSci.2265
Dissertations / Theses on the topic "Shea tree"
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Poudyal, Mahesh. "Tree tenure in agroforestry parklands : implications for the management, utilisation and ecology of shea and locust bean trees in northern Ghana." Thesis, University of York, 2009. http://etheses.whiterose.ac.uk/861/.
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The management and utilisation of resources in agroforestry systems are influenced by both land and tree tenure systems, especially where land and tree tenure are distinct, and rights to one do not necessarily lead to rights over the other. Most academic research has examined the impact of land tenure on management and productivity in these landscapes. This thesis investigates the impact of tree tenure alongside other socioeconomic factors through the research question: 'how do local institutional arrangements affect the management, utilisation and ecology of indigenous economic trees in agroforestry parklands?' Shea and locust bean trees, two of the most economically, culturally and ecologically important indigenous agroforestry species in Northern Ghana, are chosen for the case study. This multidisciplinary study utilises several methodologies of data collection and analysis to assess individual and household behaviour in the management of shea and locust bean trees, and the impact on the ecology of these species. The analysis of incentives (and constraints) stemming from differing tenure arrangements reveals differing attitudes among the households to the preservation and planting of these trees on their farmlands. Women, who are primary gatherers of non-timber products from these trees and hence the main beneficiaries, have differing access to these trees, depending both upon the status of their household within the community and the tenure rules in place. Econometric modelling of shea and locust bean tree densities reveals the socioeconomic and institutional determinants of these tree densities on the farmland, highlighting the importance of economic and institutional incentives and constraints in shaping the management practices, and subsequently the ecology of these indigenous economic species. The findings demonstrate that the vagaries of the resource-use dynamics should be taken into consideration by any policy targeted towards promoting sustainable management and utilisation of these valuable parkland species.
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Boodhoo-Leegsma, Aissa. "Place, Space & Power: From Under the Baobab Tree to a Fair Trade Co-operative-Women's Experiences in Shea Butter Production in Upper East Ghana." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/34447.
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Shea butter production in West Africa has been dominated by women and Northern Ghana specifically is a leading global producer. This thesis explores women’s perceptions of power, control and agency in the Ojoba Women’s Fair Trade Co-operative in Upper East Ghana. I add to the literature on women’s experiences with and in fair trade. I examine how the shea industry and the co-operative provide a marketplace for women and a space for women to co-operate and resist power structures. I emphasize how the Western language of empowerment builds substantially from pre-existing women’s networks and labour sharing practices in the agricultural context. The thesis evaluates the factors within Ojoba that contribute to women’s empowerment. To be ‘empowered’ in Ojoba reflects a variety of understandings, experiences and locations. Indeed “women’s empowerment” may misrepresent how the women are capable of building a physical and social space of safety, debate and growth.
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Sheikha, Ali El. "Détermination de l'origine géographique des graines et fruits du Karité et du Physalis par l’utilisation d’empreintes génétiques. Étude de la communauté microbienne par PCR/DGGE. Analyse des activités biologiques d'extraits de fruits." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20084/document.
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Les échanges commerciaux s'intensifient et s'étendent à l'ensemble de la planète. Le consommateur est exigeant et sensible à la qualité et à l'origine des produits alimentaires qu'il achète. Devant la difficulté de mettre en place des systèmes documentaires dans les pays d'Afrique sub-saharienne, des nouvelles stratégies de traçabilité émergent. Parmi les nouveaux moyens de tracer les produits d'origine végétale, l'idée de créer un « code barre biologique » basé sur l'analyse des ADN de microorganismes présents sur les fruits est une piste intéressante. Cette thèse est l'objet d'étude d'un WP dirigé par D. Montet obtenu dans le cadre du projet Inco Innovkar géré par JM Bouvet de l'UR 39. Cette méthode repose sur l'hypothèse que la microflore commensale du fruit de karité est spécifique entre autre d'une zone géographique de production. L'écologie des bactéries, levures et moisissures seront étudiées par le thésard sur le karité et le Physalis, une plante à fruit de la même zone géographique à fort potentiel commercial. L'analyse biochimique des fruits ainsi que l'activité antimicrobienne de certaines molécules sera étudiée (physaline)<br>Trade intensified and spread to the entire planet. The consumer is demanding and sensitive to the quality and origin of food products they buy. Given the difficulty of setting up documentation systems in countries in sub-Saharan Africa, new strategies are emerging traceability. Among the new means of tracing products of plant origin, the idea of creating a "biological bar code" based on the analysis of DNA of microorganisms on fruit is an interesting idea. This thesis is the subject of a study conducted by D. Montet WP obtained under the Inco project managed by JM Bouvet Innovkar of UR 39. This method assumes that the commensally microflora of the fruit of Shea is among other a specific geographical area of production. The ecology of bacteria, yeasts and molds will be reviewed by the PhD student on Shea butter and Physalis, a plant with fruit of the same geographical area with high commercial potential. Biochemical analysis of fruit and antimic robial activity of certain molecules will be studied (physaline)
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Gonçalves, Meire Lisboa Santos. "CRIANDO RAÍZES, ESCALANDO ÁRVORES: Análise da tradução da obra The giving tree de Shel Silverstein." Pontifícia Universidade Católica de Goiás, 2011. http://tede2.pucgoias.edu.br:8080/handle/tede/3801.
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Previous issue date: 2011-09-05<br>Analysis of the translation in Portuguese (Brazil) of the children's story "The Giving
Tree" by Shel Silverstein, American original, Harper Collins, published in 1964. A
Portuguese translation was made by Fernando Sabino, published by Cosac Naify in
2006 with the title "A árvore generosa." The comparison between original and
translation will be done from the parameters of children’s reception given by the
relevance of their language development. The comparative analysis between original
and translation will be performed from the parameters of the children’s reception. It
will be described the methodology and procedures for passage of the source
language to target language, considering the theoretical Darbelnet and Vinay (2004),
Nida (2001/2004), Catford (1980) and Newmark (2001). It will also be mentioned
reflections of other theorists such as Goethe, Benjamin, and Derrida.<br>Análise da tradução em Língua Portuguesa (Brasil) da história infantil “The giving
tree”, de Shel Silverstein, original estadunidense, editora Harper Collins, do ano de
1964. A tradução em português foi feita por Fernando Sabino, publicada pela Cosac
Naify em 2006, com o título de “A árvore generosa”. O estudo comparativo entre
original e tradução será realizado a partir dos parâmetros da recepção infantil dada a
relevância do desenvolvimento da linguagem na criança. A análise comparativa
entre original e tradução será realizada a partir dos parâmetros da recepção infantil.
Serão descritos a metodologia e os procedimentos de passagem da língua de
partida para a língua de chegada considerando os teóricos Vinay e Darbelnet (2004),
Nida (2001/ 2004), Catford (1980) e Newmark (2001). Serão também mencionadas
reflexões de outros teóricos como Goethe, Benjamim e Derrida.
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Ewedje, Eben-Ezer. "Biologie de la reproduction, phylogéographie et diversité de l'arbre à beurre Pentadesma butyracea Sabine, Clusiaceae: implications pour sa conservation au Bénin." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209647.
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Pentadesma butyracea Sabine est l’une des quatre espèces du genre Pentadesma endémique de l’Afrique. Elle est distribuée de la Sierra Léone au Gabon dans deux grands types d’habitats :les forêts denses humides discontinues du domaine guinéo-congolais (Haute- et Basse-Guinée) et le domaine soudanien du couloir sec du Dahomey (assimilé à une barrière à l’échange de gènes et d’espèces entre les deux blocs guinéo-congolais). Dans ce dernier, l’espèce se retrouve dans des galeries forestières et occupe une place capitale dans le développement socio-économique des communautés locales en raison des multiples biens et services que procurent ses produits (alimentation, médecine et pharmacopée traditionnelle, etc.). Cependant, des pressions d’origines multiples, telles que le ramassage des graines pour fabriquer du beurre, la fragmentation de l’habitat et sa destruction en faveur du maraîchage, les pratiques culturales inadaptées, les incendies, font peser de lourdes menaces sur l’espèce.<p>Le but de ce travail est d’acquérir les connaissances requises pour la conservation et la gestion durable des ressources génétiques de l’espèce. Trois objectifs ont été définis :(i) étudier la phylogéographie de l’espèce, (ii) étudier sa variabilité morphologique et génétique au Bénin et (iii) caractériser sa biologie de reproduction. En amont de ces travaux, nous avons développé onze marqueurs microsatellites nucléaires chez P. butyracea (chapitre 2). Ils ont été utilisés pour l’étude de la phylogéographie et la diversité génétique de P. butyracea (chapitres 3 et 5), ainsi que pour étudier la dépression de consanguinité et les paramètres de son système de reproduction (chapitre 7).<p>La caractérisation de la répartition spatiale des lignées génétiques de régions intergéniques de l’ADN chloroplastique et de l’ADN ribosomal (ITS) a détecté deux lignées génétiques allopatriques entre le Haut et le Bas-Guinéen, indiquant une forte différenciation génétique et un signal phylogéographique. L’analyse des microsatellites détecte trois pools géniques correspondant aux trois régions étudiées (Haute Guinée, Dahomey Gap et Basse Guinée). La diversité génétique est faible dans le Dahomey Gap, modérée dans le Haut-Guinéen et élevée dans le Bas-Guinéen. Ces résultats indiquent une séparation très ancienne des populations d’Afrique centrale et d’Afrique de l’ouest, alors que celles du Dahomey Gap pourraient résulter des forêts denses humides de l’Afrique de l’ouest lors de la période Holocène humide africaine. Dans ce couloir sec, les populations ont subi une forte dérive génétique, potentiellement due à des évènements de fondation. Au Bénin, deux groupes éco-morphologiques ont été détectés suivant un gradient nord-sud, contrastant avec deux pools géniques présentant une distribution est-ouest. <p>P. butyracea est une espèce auto-compatible majoritairement allogame. La corrélation de paternité est plus élevée aux niveaux intra-fruit vs. inter-fruits, et au sein d’une population de petite taille vs. de grande taille. Les principaux pollinisateurs au Bénin sont deux oiseaux (Cyanomitra verticalis, Cinnyris coccinigastrus) et trois abeilles (Apis mellifera, Meliponula togoensis, Hypotrigona sp.). La productivité totale en fruits augmente en fonction de l’âge de l’arbre et varie en fonction de l’année, atteignant un pic pour les arbres ayant un diamètre de 60-80 cm. Les graines sont récalcitrantes et ont une teneur en eau de 42.5 ± 2.9 %. <p>L’analyse des paramètres de reproduction et de diversité génétique, associés aux facteurs écogéographiques, nous a permis de proposer un échantillon de neuf populations représentatives de la diversité à l’échelle du Bénin, dans la perspective d’une conservation in situ. Le succès de celle-ci dépendra des efforts conjugués des communautés locales, de la recherche forestière et de la définition d’un cadre législatif par le politique pour la protection des habitats. La conservation ex situ est envisagée sous forme d’un verger rassemblant diverses origines, présentant l’intérêt supplémentaire de permettre d’étudier les contributions de la diversité génétique et de la plasticité phénotypique à la variation phénotypique. / Pentadesma butyracea Sabine is one of the four species of the endemic genus Pentadesma in Africa. The species is distributed from Sierra Leone to Gabon in two major types of habitats: the discontinuous and dense Guineo-Congolian rainforests (Upper and Lower Guinea) and the Sudanian domain of the dry corridor of Dahomey (considered as a barrier to the exchange of genes and species between Upper and Lower Guinea). In the latter, the species is found in gallery forests and plays a vital role in the socio-economic livelihood of local communities due to the various resources and services that provide its products (food, medicine and traditional, etc.). However, pressure from many sources including the collection of seeds to make butter, habitat fragmentation and its destruction for market gardening, inadequate agricultural practices, fires, are serious threats to the species.<p>The aim of this work was to acquire appropriate knowledge for the conservation and sustainable management of genetic resources of the species. Three objectives were defined (i) study the phylogeography of the species; (ii) evaluate its morphological and genetic variability in Benin; and (iii) characterize its reproductive biology. In a preliminary work, eleven nuclear microsatellite markers of P. butyracea were developed (Chapter 2). They were used for the study of phylogeography and genetic diversity of P. butyracea (chapters 3 and 5), and to study the inbreeding depression and parameters of its breeding system (Chapter 7).<p>The characterization of the genetic lineages and their spatial distribution using intergenic regions from chloroplast DNA and ribosomal DNA (ITS) region detected two allopatric genetic lineages between Upper and Lower Guinea, indicating a high genetic differentiation and a phylogeographic signal. Microsatellite markers allowed us to detect three genepools matching with the three studied regions (Upper Guinea, Dahomey-Gap and Lower Guinea). Genetic diversity was low in the Dahomey Gap, moderate in Upper Guinea and high in Lower Guinea. These results indicate an ancient separation of populations from Central and West Africa, while those from Dahomey Gap could originate West African rainforests (Upper Guinea) during the African humid Holocene period. In this dry corridor, populations experienced high genetic drift, possibly due to founding events. In Benin, two eco-morphological groups were detected following a north-south gradient, contrasting with two gene pools presenting an east-west distribution.<p>Pentadesma butyracea is a self-compatible, mainly allogamous species. The correlation of paternity was higher within-fruit vs. among-fruits, and in population of small size vs. large size. The main pollinators in Benin are two birds (Cyanomitra verticalis, Cinnyris coccinigastrus) and three bees (Apis mellifera, Meliponula togoensis, Hypotrigona sp.). Total productivity in fruit increases with tree age and varies yearly, reaching a peak for trees of 60-80 cm of diameter class. Seeds are recalcitrant (i.e. they cannot be conserved at low temperature), having a water content of 42.5 ± 2.9% at maturity.<p>The analysis of reproduction and genetics parameters, associated with eco-geographic factors, enabled us to select nine populations representative of the diversity in Benin, from the perspective of in situ conservation. The success of the latter will depend on combined efforts of local communities, forest research and an adequate legislative framework for the protection of habitats. Ex situ conservation is envisaged as an orchard assembling various origins, and would have the additional advantage of allowing to study the contribution of genetic diversity and phenotypic plasticity to phenotypic variation.<br>Doctorat en Sciences<br>info:eu-repo/semantics/nonPublished
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Swiatlo, Jeffrey A. "Analysis of shear damage to southern pine lumber." Thesis, Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53188.
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This study was conducted as a second part in the shear damage research project at Virginia Tech. The objectives were to verify the results obtained by Gallagher (1984) in the first study under normal mill operations as well as develop a method to compare and evaluate the extent of shear damage in relation to other defects present in southern pine lumber. This was accomplished through two sawmill studies and two kiln cart surveys performed in different geographic locations.
Visible indicators such as stump-pull that are used to determine shear damage extent are often misleading. Stump-pull, used as a scaling deduction for shear damage, does not fully determine the extent of shear damage present. Shatter is often present in greater amounts over the cross section of the butt of the log. The recommendation of six inches of butt trim that was determined to minimize value losses in the first study is supported by the results obtained in this research. A trim of six inches removed 94 to 99 percent of shear damage in this study.
Defects other than shear damage were present on dried and surfaced lumber. Drying checks and splits along with shake were often observed on the lumber ends. These defects often extend further up on the lumber ends, past the seven inch simulated trim. Shake was determined to be the limiting defect. Shatter, in the absence of shake, was determined to be limiting.
Kiln cart surveys conducted at mills that utilize a large percentage of sheared logs can be an inexpensive and effective tool to enable mill personnel to determine the extent of shear damage in relation to other defects present on lumber ends based on green trim already taken.<br>Master of Science
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Yip, Chiu-wah Regina, and 葉昭華. "The impact of new town development on urban trees in Hong Kong." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B43894227.
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Birnbaum, Ruth. "An exposition of Joseph Ibn Shem Tov's "Kevod Elohim", "The Glory of God", a fifteenth-century philosophical work : on the Summum Bonum of man and the true happiness /." Lewiston (N.Y.) : E. Mellen, 2001. http://catalogue.bnf.fr/ark:/12148/cb38937367f.
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Allen, Jared Seth. "DETERMINING SOUTH MISSISSIPPI FOREST SUSCEPTIBILITY TO WINDTHROW AND SHEAR DAMAGE IN A HURRICANE ENVIRONMENT THROUGH DATA MINING OF METEOROLOGICAL, PHYSIOGRAPHICAL,PEDOLOGICAL, AND TREE LEVEL DATA." MSSTATE, 2009. http://sun.library.msstate.edu/ETD-db/theses/available/etd-08262009-143122/.
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An estimated 39 million m<SUP>3</SUP> of timber was damaged across the Southeast Forest District of Mississippi due to Hurricane Katrina. Aggregated forest plot-level biometrics was coupled with wind, topographical, and soil attributes using a GIS. Data mining through Regression Tree Analysis (RTA) was used to determine factors contributing to shear damage of pines and wind-throw damage of hardwoods. Results depict Loreys Mean Height (LMH) and Quadratic Mean Diameter (QMD) are important variables in determining the percentage of trees and basal area damaged for both forest classes with sustained wind speed important for wind-throw and peak wind gusts for shear. Logistic regression based on stand damage classification compared to RTA revealed LMH, stand height to diameter ratio, and sustained wind variable concurrence. Reclassification of MIFI plot damage calls based on percentage of trees damaged increased predictability of wind-throw and shear classification. This research can potentially aid emergency and forest managers for better mitigation and recovery decisions following a hurricane.
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Cano, Batalla Jordi. "Evaluación mecánica in vitro de tres cementos mediante shear bond strenght y mediante restauraciones unitarias sobre implantes con y sin termociclado." Doctoral thesis, Universitat Internacional de Catalunya, 2010. http://hdl.handle.net/10803/9343.
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En el presente estudio in vitro se evaluó el comportamiento de tres cementos (RelyxTemp NE, Dentotemp y Dentocem) utilizados en restauraciones unitarias sobre implantes. Para la evaluación de los tres cementos se realizaron pruebas de adhesión (test de shear bond strenght) y pruebas de resistencia a la tracción mediante una máquina de tracción universal. En los test de adhesión se analizó el comportamiento de los cementos en tres superficies distintas (titanio pulido, titanio arenado y cromo-cobalto) que se corresponden con las superficies que encontramos en los test de retención (pilar, pilar arenado y corona) . En los test de tracción también se tuvieron en consideración algunos de los factores que pueden afectar a la retención; la altura del pilar (se estudió la retención en pilares de 6, 5 y 4 mm), la textura del pilar (se utilizaron pilares arenados mediante partículas de óxido de alúmina). En ambos estudios se consideró el envejecimiento de los cementos mediante un proceso de termociclado. Tanto en los estudios de adhesión como en los estudios de retención, se observó mediante microscopia óptica, el tipo de fallo que aparecía (adhesivo o cohesivo) tras la realización de los test. Los resultados se analizaron mediante análisis de la varianza (ANOVA) y para la evaluación del tipo de fallo se realizó un test de Chi-cuadrado.
Books on the topic "Shea tree"
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Gwali, Sam. Cost-benefit analysis for shea butter use options in the districts of Abim, Agago, Kitgum and Otuke: Final report. National Environment Management Authority (NEMA), 2016.
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1932-, Hall J. B., and University of Wales, Bangor. School of Agricultural and Forest Sciences., eds. Vitellaria paradoxa: A monograph. School of Agricultural and Forest Sciences, University of Wales, 1996.
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Consultative Regional Workshop on Shea Product Quality and Production Certification System Design (2004 Bamako, Mali). Proceedings: Consultative Regional Workshop on Shea Product Quality and Production Certification System Design. FAO, 2006.
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Séminaire international sur le séchage et sur la valorisation du karité et de l'aiélé (1999 Ngaoundéré, Cameroon). Séminaire international sur le séchage et sur la valorisation du karité et de l'aiélé: Ngaoundéré, Cameroun, 1-3 décembre 1999. Presses universitaires de Yaoundé, 2000.
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Nerd, Avinoʻam. Inṭroduḳtsyah shel ʻatse peri ḥadashim: Duaḥ mesakem, 1985-1991. ha-Mekhonim le-meḥḳar shimushi, Universiṭat Ben-Guryon ba-Negev, 1991.
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editor, Bernstein Ilana, ред. ha-Himnon shel ha-ʻets ha-meguban: The anthem of the hunchback tree. Shulḥan ketivah, 2019.
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Alon, Azaria. ʻEts ṿa-śiaḥ: ʻetsim, śiḥim u-meṭapsim shel Erets-Yiśraʼel. ha-Ḥevrah la-haganat ha-ṭevaʻ, 1991.
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1943-, Westenholz Joan Goodnick, та Muzeʼon artsot ha-Miḳra (Jerusalem), ред. Birkat ha-arets ha-ṭovah: Shivʻat ha-minim shel Erets-Yiśraʼel. Muzeʼon artsot ha-Miḳra, 1998.
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Pollak, Amir. Sipurah he-ʻatsuv shel Yah-Yah: Parpar ṭaṿai ha-meshi : YaYa's sad story : Silkworm of the mulberry tree. Marom Tarbut Yiśreʼelit, 2016.
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Farhand, Moses. Sefer Birkat ha-Shem: Leket dine isur ḳetsitsat ilane maʼakhal ... Mosheh Yitsḥaḳ Farhand, 2001.
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Sommer, Marianne. "Postscript." In The Diagrammatics of ‘Race’. Open Book Publishers, 2024. http://dx.doi.org/10.11647/obp.0396.25.
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The long history of relating diagrams revealed in the book does not crystallize into a linear development, such as from chain to tree to net. There were different kinds in competition at all times and compounds of elements from various types. Net structures were early diagrams to capture natural orders, trees may still transport the meaning of a progressive and serial arrangement or evolution, while chains in natural history multiplied to form ‘trees’, nets, or other three-dimensional structures. Trees and maps were often combined, and tree-like shapes incorporated network aspects. Anthropological diagrams might have been inspired by religious and secular genealogies and maps, breeding pedigrees, even arbores consanguinitates, and by forms used in natural history more generally as well as in other sciences like linguistics and embryology. Although particular diagrams are strongly associated with specific conceptions, and even while they are always part of political practices, there was no universal alignment of, for instance, a tree diagram with, for example, a belief in the existence of clearly demarcated ‘races’. At the same time, the diagrams that relate humans in physical, evolutionary, and genetic anthropology have been connected to programs to collect human substances such as bones and blood. In the postscript I look at current issues and controversies surrounding such collections and once again think about the nature of relating diagrams. I conclude by examining some intriguing artworks that shed further light on these themes.
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Moricca, Salvatore, Gloria Innocenti, and Alessandro Ragazzi. "Epidemiological Investigations Shed Light on the Ecological Role of the Endophyte Phomopsis quercina in Mediterranean Oak Forests." In Endophytes of Forest Trees. Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-89833-9_10.
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Dryden, Linda. "She: Gothic Reverberations in Star Trek: First Contact." In Postfeminist Gothic. Palgrave Macmillan UK, 2007. http://dx.doi.org/10.1057/9780230801301_12.
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Pomsen, Chanida, Papaporn Roipromma, and Sopa Nudang. "Nature Materials Packing Design for Food Container Using the Leaf Sheaf Banana Tree." In Advanced in Creative Technology- added Value Innovations in Engineering, Materials and Manufacturing. Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-59164-8_14.
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Norris, J. E., and J. R. Greenwood. "Review of in situ shear tests on root reinforced soil." In The Supporting Roots of Trees and Woody Plants: Form, Function and Physiology. Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-017-3469-1_28.
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Tripathi, Neil, Shashank Shekhar Sandilya, Bhabani Shankar Das, Kamalini Devi, and Jnana Ranjan Khuntia. "Shear Stress Estimation in Compound Channel Using M5 Tree and XGBoost Soft Computing Techniques." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2025. https://doi.org/10.1007/978-981-97-8035-8_30.
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Pratt, Susie. "Trees and Landlords and Other Public Experiments." In Covert Plants. punctum books, 2018. https://doi.org/10.21983/p3.0207.1.18.
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In 2012, while I was an art medic-in-residence at the Environmen-tal Health Clinic in New York, the director of the Clinic, Nata-lie Jeremijenko, showed me her designs for a co-working office space in a tree. The plans were still in the early stages, but what caught my attention was her articulation of how a tree would be set up as the landlord of the office. The rent people paid for us-ing the co-working space would be put in the service of its own interests, for example to improve soil quality or for companion planting. The TREExOFFICE, as she called it, was to be installed in Socrates Sculpture Park as part of the exhibition Civic Ac-tion — this was the first of many iterations of this intervention. I was curious to talk with Natalie to find out how the project had evolved. What is it like to have a tree as a landlord? How did tenants behave? How can a tree engage a community to serve it’s own and collective interests? How can public experiments, such as TREExOFFICE, help to re-imagine and re-design our re-lationship to natural systems?
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Liu, Yongjian, Lan Luo, You Zhang, Mingyang Lai, and Yangpan Fu. "Triaxial Experimental Study on Strength Characteristics of Saturated Soft Soil Under Different Shear Strain Rates." In Lecture Notes in Civil Engineering. Springer Nature Singapore, 2024. http://dx.doi.org/10.1007/978-981-97-5814-2_14.
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AbstractThe China Nansha District of Guangzhou City is located at the geographical center of the Pearl River estuary and the Greater Bay Area of Guangdong, Hong Kong, and Macau, is characterized by widely distributed saturated soft soil layers with poor engineering properties. Although many scholars have explored the influence of loading rate on the mechanical properties of soft soil, research on the variation of undrained shear strength of saturated soft soil under different shear strain rates is still limited. This article conducts an in-depth analysis of the mechanical behavior of saturated soft soil under different strain rates through true triaxial consolidated undrained shear tests. Under load, these layers exhibit a significant rate-dependent mechanical behavior. In order to reveal the influence of shear strain rate on the mechanical properties of highly saturated soft soils based on SPAX-2000 test system, a series of true triaxial consolidation undrained shear tests were carried out under different confining pressures and different strain rates, variation rules of undrained shear strength of saturated soft and the pore water pressure with strain rate were analyzed. The experimental results indicate that the strain-rate softening exists in saturated soft soil. Under the same consolidation conditions, the relative growth rate of shear strength is a monotonic increasing function of the logarithm of shear strain rate, and the smaller the intermediate principle stress, the more significant the effect of shear strain rate on shear strength. During the shearing process (The strain-rate range from 10–6/s to 10–2/s), the undrained shear strength of saturated soft soil increases with the growth of shear strain rate, following an exponential variation pattern. In the early stages of loading, the increase in pore water pressure and the maximum pore water pressure are significantly affected by the strain rate. Throughout the testing process, the variation of pore water pressure exhibits some fluctuation and hysteresis. Different from strongly structured clay, the strength of saturated soft soil undergoes a progressive change with the shear strain rate, without showing a distinct critical rate of transition.
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Treu, Martina. "Implacabile Elettra: Figlia Sorella Guerriera." In Le forme del sentire. LED Edizioni Universitarie, 2019. http://dx.doi.org/10.7359/1124-2023-trem.
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Elektra, daughter of Agamemnon and Clytemnestra, is an extraordinary example among ancient characters, as she is depicted with variations by all three Greek major playwrights, in four surviving tragedies: Aeschylus (Libation Bearers), Sophocles (Elektra), and Euripides (Elektra and Orestes). As for modern reception, she is still very popular in theatre as well as in literature, arts, and different medias (films, novels, poems, comics). After a survey on the ancient sources, we focus on less known and most recent case-studies, which show in our opinion new, interesting features compared to her past appearances.
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Gatrell, V. A. C. "Anxiety And Defence." In The Hanging Tree. Oxford University PressOxford, 1994. http://dx.doi.org/10.1093/oso/9780198204138.003.0010.
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Abstract In 1813 The Novelist Maria Edgeworth Pertly Wrote To A friend that she was pleased to live in an age when newspapers ‘give subjects of conversation in common to people in the most distant parts of the country’. She was particularly grateful that executions were one of the subjects, because execution reports exposed the variety of human character wonderfully. ‘Do you recollect’, she chatted gaily, ‘our seeing in the news-paper an account of a man who poisoned several racehorses by putting arsenic in the water-troughs? Also an account of a horrid woman who made her servant boy murder her husband; and ordered him to go back and finish him as composedly as if she had told him to kill a pig?’ When this man was brought out for execution, he was more cool and com posed than any other person present. When the cord was to be put about his neck it was perceived that it was too short and that it could not well reach him. He pointed to the hassock on which he had been kneeling and made a sign to them to put it under his feet! The woman who murdered her husband was an extraordinary compound of insensibility and sensibility. While sentence was pronouncing upon her, she shewed no symptom of feeling, but from the moment she was condemned she would not let any creature see her face. She kept it constantly hid, even till she was executed. On hearing the sermon the evening before her execution, she wept and sobbed bitterly yet in the morning seemed quite insensible and eat [sic] a hearty breakfast.
Conference papers on the topic "Shea tree"
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Liu, Yimin, Yuqing Liu, Hongxi Liu, Xiaoqing Xu, and Yiyan Chen. "Shear Resistance Prediction of Angle Connectors Using Machine Learning." In IABSE Symposium, Tokyo 2025: Environmentally Friendly Technologies and Structures: Focusing on Sustainable Approaches. International Association for Bridge and Structural Engineering (IABSE), 2025. https://doi.org/10.2749/tokyo.2025.1564.
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<p>Machine learning techniques were used to predict the shear resistance of angle shear connectors. A database of 151 experimental datasets from push-out tests was constructed, identifying eight critical features. Three predictive models were constructed: Support Vector Regression (SVR), Artificial Neural Networks (ANN), and Gradient Boosting Decision Trees (GBDT). The ANN model demonstrated superior predictive accuracy and generalization. The SHapley Additive exPlanations (SHAP) method identified the length of the angle shear connector as the most influential factor, while the height had minimal impact. Partial Dependence Plots and Individual Conditional Expectation (PDP-ICE) visualized feature influences on predictions, providing insight into the relationships between key parameters and shear resistance.</p>
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Davis-Amendola, Kerry L., Luis A. Ortiz-Flores, K. M. Abu Hurayra Lizu, Bryan Huey, and Yang Cao. "Conductive Atomic Force Microscopy to Shed New Light on Surface Electrical Trees." In 2024 IEEE Conference on Electrical Insulation and Dielectric Phenomena (CEIDP). IEEE, 2024. https://doi.org/10.1109/ceidp61745.2024.10907663.
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Jawaharlal, Mariappan, Gustavo Vargas, and Lorenzo Gutierrez. "The Plant Kingdom in Engineering Design: Learning to Design From Trees." In ASME 2017 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2017. http://dx.doi.org/10.1115/imece2017-72497.
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A tree may be the earliest multifunctional structure, and wood is the oldest known engineering material. Yet, trees have no place in engineering education. If we view a tree from merely a mechanical or civil engineering perspective, engineering mechanics can be learned from the tree’s example. Trees have survived by adapting to the most difficult circumstances: heavy winds, rains, floods, droughts, earthquakes, mammal damage, human intervention, etc. The root system must be strong and flexible enough to support the tree’s entire structure from varying load conditions and to provide food storage and nutrient transfer. The stem system provides structural support for the tree’s above-the-ground parts and transfers water and nutrients from the roots through the network of thick-walled cells to other parts of the tree. Leaves produce food and form the surface area surrounding the tree. Leaves come in a variety of shapes and sizes. The tree’s crown, comprising branches, leaves, and reproductive elements, help the tree to catch more sunlight. It moves upward and outward to expose more of its leaves to direct sunlight for photosynthesis while maintaining physical balance on the earth. A tree’s lifecycle can span hundreds of years, despite its vulnerability to constantly changing loads throughout the day and throughout its life. In monsoon and windy seasons, trees endure extremely difficult fatigue-loading. Various parts of the tree and its stem are subjected to combined loading conditions: tension, compression, shear, bending, and torsion. Trees develop and adapt stress management strategies by adjusting their shapes to the type or level of stress they endure: they add more mass where more strength is needed, allows material to easily break off (or physiologically inactive) from locations where it is not necessary, design optimum shapes, and create variable notch radii for reducing stress concentration. But a tree is much more than a structural member. It provides food and shelter for wildlife. It absorbs atmospheric carbon dioxide and produces oxygen. It lowers air temperature and facilitates the water cycle. Structural analysis of a tree can benefit engineering students and practicing engineers alike. Furthermore, a deeper understanding of trees can help us to create multifunctional designs that are in a symbiotic relationship with other members in the system. In short, studying tree mechanics can help us to become better engineers. This paper presents our efforts to integrate trees into engineering curricula to teach mechanics ranging from equilibrium study to stress analysis. Students of statics, dynamics, the strength of materials, stress analysis, material science, design, etc., can benefit from learning about trees. This approach enables students to understand the complexities of real-world living systems, appreciate the genius of nature’s design, and develop methods for creating sustainable designs.
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Sampaio, Valzeli. "Wish Mango Tree: hybrid experimentation and creation." In LINK 2021. Tuwhera Open Access, 2021. http://dx.doi.org/10.24135/link2021.v2i1.109.
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This essay presents the process of creating the artistic project at augmented reality “Wish Mango Tree” is configured as a specific site / public intervention for installing in the georeferenced mango trees of the city of Belém a technological device for electronic labeling and the creation of a hollow steel plate at mango tree. This process involves experimentation and creation related to Visual Arts, Design and programming, experienced through a mobile application, being a physical hybrid intervention. “Wish Mango Tree” is inspired by the work “Wish Tree” , a series of art installations in process, started in 1981, by the Japanese artist, and member of the Fluxus group, Yoko Ono. She chooses a tree native to a place, or plants one under her guidance. The public is invited to tie a wish in writing and hang it on the tree. Yoko has already installed this work in some cities in the world. “Wish Mango Tree” proposes an action similar to the public and passers-by of the mango trees in Belém. The project promotes interaction between individuals: humans and mango trees. Digital content can be viewed in the augmented reality app at the site specific where mango leaf wishes can be accessed by anyone. “Mangueira Desejo” seeks to fill a gap or lack identified: the invisibility of mango trees, seeking to use technology to give visibility to a social and ecological problem. The political dimension of the project is revealed in giving visibility to the mango trees, activating the collective memory and provoking questions and commitments from the individuals involved: trees, people, and institutions. This artistic project aimed at experimentation and creation related to Visual Arts and Design, experienced through a mobile application. And evokes the affective memory of its participants, seeking to enhance, strengthen and maintain the identity and cultural memory of Pará through digital media. The project fits into the artistic and cultural area: Visual Arts, with the creation of proposals in the Visual Arts area, through the areas: installation, intervention mechanisms, specific site, urban art, digital art, new media, photography , being a hybrid proposal between art and digital design. In addition to addressing the experience of the visual arts in their technical, formal and conceptual reflections, of creation, diffusion, training and memory. In this sense, the project promotes creation, experimentation and design associated with a historical, social, cultural, sustainable and / or technological context, which can be translated into propositional actions that address graphic design, interactive media, web design/applications, design of games. The mango trees themselves are objects of public interest, the app invites everyone to “hang” their desires on the “Wish Mango Trees ”, promoting the transformation of the mango trees into a receptacle for the aspirations of the people who cross it. The app will promote remotely a network experience that triggers a physical experience in the main mango trees of the square, when approaching a mango tree to start the action, which will give visibility to the cloud of annotations at mango leaves through mobile app.
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Papoutsakis, Andreas, Sergei Sazhin, Steven Begg, Ionut Danaila, and Francky Luddens. "A new approach to modelling the two way coupling for momentum transfer in a hollow-cone spray." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4671.
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A new approach to modelling the interaction between droplets and the carrier phase is suggested. The new model isapplied to the analysis of a spray injected into a chamber of quiescent air, using an Eulerian-Lagrangian approach. The conservative formulation of the equations for mass, momentum and energy transport is used for the analysis of the carrier phase. The dispersed phase is modelled using the Lagrangian approach with droplets represented by individual parcels.The implementation of the Discontinuous Galerkin method (ForestDG), based on a topological representation of the computational mesh by a hierarchical structure consisting of oct- quad- and binary trees, is used in our analysis. Adaptive mesh refinement (h-refinement) enables us to increase the spatial resolution for the computational mesh in the vicinity of the points of interest such as interfaces, geometrical features, or flow discontinuities. The local increase in the expansion order (p-refinement) at areas of high strain rates or vorticity magnitude results in an increase of the order of the accuracy of discretisation of shear layers and vortices.The initial domain consists of a graph of unitarian-trees representing hexahedral, prismatic and tetrahedral elements. The ancestral elements of the mesh can be split into self-similar elements allowing each tree to grow branches to an arbitrary level of refinement. The connectivity of the elements, their genealogy and their partitioning are described by linked lists of pointers. These are attached to the tree data structure which facilitates the on-the-fly splitting, merging and repartitioning of the computational mesh by rearranging the links of each node of the tree. This enables us to refine the computational mesh in the vicinity of the droplet parcels aiming to accurately resolve the coupling betweenthe two phases.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4671
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Plotnikov, Andrey, and Alla Levina. "Algorithm for simplifying the SHA-256 operations tree." In 2023 IEEE International Conference on Cyber Security and Resilience (CSR). IEEE, 2023. http://dx.doi.org/10.1109/csr57506.2023.10224939.
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Hau, Jan-Niklas, Martin Oberlack, George Chagelishvili, George Khujadze, and Alexander Tevzadze. "TRUE SOURCES OF LINEAR SOUND IN PLANE COUETTE FLOW." In Eighth International Symposium on Turbulence and Shear Flow Phenomena. Begellhouse, 2013. http://dx.doi.org/10.1615/tsfp8.1430.
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Meng, Meng, Luke P. Frash, J. William Carey, Nathan J. Welch, Wenfeng Li, and Samantha K. Peterson. "Triaxial Direct-shear Reveals the True Magnitude of Shear Fracture Roughness Effects on Flow." In Unconventional Resources Technology Conference. American Association of Petroleum Geologists, 2021. http://dx.doi.org/10.15530/urtec-2021-5536.
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van der Giessen, Alina G., Frank J. H. Gijsen, Jolanda J. Wentzel, Harald C. Groen, Anton F. W. van der Steen, and Frans N. van de Vosse. "Comparison of Outflow Condition Models on the Effect of Wall Shear Stress Distribution in Patient Specific Coronary Trees." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-192774.
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It is well established that atherosclerosis originates in low wall shear stress (WSS) regions near bifurcations and in curved segments of the coronary tree [1]. WSS also seems to influences plaque progression and destabilization, which explains the large interest in accurate assessment of the WSS.
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Choi, Ricky Y. S., and Arthur K. O. So. "On the Application of Mechanical Reinforcement of Tree Roots to Slope Stabilization." In The HKIE Geotechnical Division 41st Annual Seminar. AIJR Publisher, 2022. http://dx.doi.org/10.21467/proceedings.126.24.
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The root strengthening effects on soil behind retaining walls may be quantified by a simplified equation ΔS = 1.2TR(AR/A) where ΔS, TR and AR/A are the shear strength increase, tensile strength of root and root area ratio respectively. However, this effect is ignored during stability analysis due to the possible significant variability of the potential beneficial effect and extreme difficulty in fully characterizing the tree roots and quantifying their effects. In this paper, advancements in the last few decades in biotechnical slope stability are reviewed. Representative models to quantify the mechanical effects of tree roots are studied. If other potential beneficial effects due to existence of roots and suction effect due to transpiration of tree are ignored, the term 1.2, root tensile strength and root area ratio may still be the three key parameters to the root strengthening effect in slope stability.
Reports on the topic "Shea tree"
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Perlow, Jason, Dan Brown, Hilary Carter, and Clyde Seepersad. The 2021 Open Source Jobs Report: 9th Annual Report on Critical Skills, Hiring Trends, and Education. The Linux Foundation, 2021. https://doi.org/10.70828/qszo6369.
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Much of the world is rebounding from the economically crippling lockdowns of COVID-19, and hiring people with the right skills is proving to be a challenge. Nowhere is this more true than in the technology sector. The talent gap that existed before the pandemic has worsened due to an acceleration of cloud-native adoption as remote work has gone mainstream. With talent shortages around the globe, training existing staff has become even more important to meet the needs of migrations to the cloud and leverage open source technologies tied to those migrations. To shed light on these changes and challenges, the Linux Foundation, once again, teamed up with edX to produce our 9th annual Open Source Jobs Report. The 2021 report provides actionable insights on the state of open source talent that employers can use to inform their hiring, training, and diversity awareness efforts. It also provides IT professionals with clear, unbiased insights on which skills are most marketable and how reskilling and certifications benefit job seekers as a differentiator in the hiring process.
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Kvalbein, Astrid. Wood or blood? Norges Musikkhøgskole, 2018. http://dx.doi.org/10.22501/nmh-ar.481278.
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Wood or Blood? New scores and new sounds for voice and clarinet Astrid Kvalbein and Gjertrud Pedersen, Norwegian Academy of Music What is this thing called a score, and how do we relate to it as performers, in order to realize a musical work? This is the fundamental question of this exposition. As a duo we have related to scores in a variety of ways over the years: from the traditional reading and interpreting of sheet music of works by distant (some dead) composers, to learning new works in dialogue with living composers and to taking part in the creative processes from the commissioning of a work to its premiere and beyond. This reflective practice has triggered many questions: could the score for instance be conceptualized as a contract, in which some elements are negotiable and others are not? Where two equal parts, the performer(s) and the composer might have qualitatively different assignments on how to realize the music? Finally: might reflecting on such questions influence our interpretative practices? To shed light on these issues, we take as examples three works from our recent repertoire: Ragnhild Berstad’s Vevtråd (Weaving thread, 2010), Jan Martin Smørdal’s The Lesser Nighthawk (2012) and Lene Grenager’s Tre eller blod (Wood or blood, 2005). We will share – attempt to unfold – some of the experiences gained from working with this music, in close collaboration and dialogue with the composers. Observing the processes from a certain temporal distance, we see how our attitudes as a duo has developed over a longer span of time, into a more confident 'we'.
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Pullammanappallil, Pratap, Haim Kalman, and Jennifer Curtis. Investigation of particulate flow behavior in a continuous, high solids, leach-bed biogasification system. United States Department of Agriculture, 2015. http://dx.doi.org/10.32747/2015.7600038.bard.
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Recent concerns regarding global warming and energy security have accelerated research and developmental efforts to produce biofuels from agricultural and forestry residues, and energy crops. Anaerobic digestion is a promising process for producing biogas-biofuel from biomass feedstocks. However, there is a need for new reactor designs and operating considerations to process fibrous biomass feedstocks. In this research project, the multiphase flow behavior of biomass particles was investigated. The objective was accomplished through both simulation and experimentation. The simulations included both particle-level and bulk flow simulations. Successful computational fluid dynamics (CFD) simulation of multiphase flow in the digester is dependent on the accuracy of constitutive models which describe (1) the particle phase stress due to particle interactions, (2) the particle phase dissipation due to inelastic interactions between particles and (3) the drag force between the fibres and the digester fluid. Discrete Element Method (DEM) simulations of Homogeneous Cooling Systems (HCS) were used to develop a particle phase dissipation rate model for non-spherical particle systems that was incorporated in a two-fluid CFDmultiphase flow model framework. Two types of frictionless, elongated particle models were compared in the HCS simulations: glued-sphere and true cylinder. A new model for drag for elongated fibres was developed which depends on Reynolds number, solids fraction, and fibre aspect ratio. Schulze shear test results could be used to calibrate particle-particle friction for DEM simulations. Several experimental measurements were taken for biomass particles like olive pulp, orange peels, wheat straw, semolina, and wheat grains. Using a compression tester, the breakage force, breakage energy, yield force, elastic stiffness and Young’s modulus were measured. Measurements were made in a shear tester to determine unconfined yield stress, major principal stress, effective angle of internal friction and internal friction angle. A liquid fludized bed system was used to determine critical velocity of fluidization for these materials. Transport measurements for pneumatic conveying were also assessed. Anaerobic digestion experiments were conducted using orange peel waste, olive pulp and wheat straw. Orange peel waste and olive pulp could be anaerobically digested to produce high methane yields. Wheat straw was not digestible. In a packed bed reactor, anaerobic digestion was not initiated above bulk densities of 100 kg/m³ for peel waste and 75 kg/m³ for olive pulp. Interestingly, after the digestion has been initiated and balanced methanogenesis established, the decomposing biomass could be packed to higher densities and successfully digested. These observations provided useful insights for high throughput reactor designs. Another outcome from this project was the development of low cost devices to measure methane content of biogas for off-line (US$37), field (US$50), and online (US$107) applications.
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Excavator killed using skid-steer loader and tree shear attachment. U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, 2002. http://dx.doi.org/10.26616/nioshsface01ia042.
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