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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
221

Estrutura de comunidades de formigas (Hymenoptera: Formicidae) do planalto do Itatiaia, Rio de Janeiro, Brasil

Martins, Luciano 25 February 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-28T13:42:46Z No. of bitstreams: 1 2011 - Luciano Martins.pdf: 2085328 bytes, checksum: e82ea56c9ce66ac46b97ad748fb1de5a (MD5) / Made available in DSpace on 2016-07-28T13:42:46Z (GMT). No. of bitstreams: 1 2011 - Luciano Martins.pdf: 2085328 bytes, checksum: e82ea56c9ce66ac46b97ad748fb1de5a (MD5) Previous issue date: 2011-02-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aims to compare three sampling techniques to estimate species richness of ants (Hymenoptera: Formicidae) in ?campos of altitude? at Itatiaia National Park, in Rio de Janeiro state. Compared richness estimates for genera and species, and curves of accumulation of species for sardine baits, pitfall traps and manual collecting are presented for two distinct sites ("steppe vegetation" [VE] and "rupicola vegetation" [VR]) in Itatiaia Plateau. The three techniques collected 31 species of 10 genera belonging to four subfamilies. In VE were registered 50% of genera and 36.4% of species collected exclusively by baits, and 20% and 50% by pitfall traps, respectively. In VR were registered 37.5% of genera and 47.61% of species exclusive for baits, but no one genus and species was restricted for manual collecting. In the case of ?campos de altitude? and when only one technique can be used, the sardine bait was the most efficient sample technique to registered richness at VE. For VR, the manual collecting was the most appropriate technique to record species richness. However, the pitfalls (in VE) and bait (in VR) recorded an important portion of species richness. In our data, the manual collecting were associated with standardized data collecting protocols, and, although much criticized, have shown effectiveness in recording species in habitats where widespread techniques cannot be used. In spite of different physiognomies show differentiated efficiency for samples techniques, it is relevant to using more than one technique associated to a colleting protocol well structured to potentiated the record of the new species in environments as the ?campos de altitude?. / O presente trabalho tem por objetivo comparar tr?s t?cnicas de coleta para estimar a riqueza de esp?cies de formigas (Hymenoptera: Formicidae) no Planalto do Itatiaia , Rio de Janeiro, Brasil. S?o apresentados dados comparativos das estimativas da riqueza de g?neros, de esp?cies e as curvas de acumula??o de esp?cies amostradas com iscas de sardinha, armadilhas de queda e coletas manuais, em duas fisionomias distintas (?vegeta??o est?pica? [VE] e ?vegeta??o rup?cola? [VR]), no Planalto do Itatiaia. Com a utiliza??o das tr?s t?cnicas foram coletadas 30 esp?cies de 11 g?neros, pertencentes a quatro subfam?lias. Para a VE foram registrados 50% dos g?neros e 36,4% das esp?cies coletadas exclusivamente pelas iscas, e 20% e 50% pela armadilha de queda, respectivamente. Para a VR foram registrados 37,5% e 47,61% dos g?neros e esp?cies exclusivas para iscas, por?m nenhum g?nero e esp?cie foram restritos a coleta manual. Em se tratando de ecossistema de campos de altitude e quando apenas uma das t?cnicas possa ser utilizada, a isca de sardinha foi a mais eficiente para amostrar a riqueza em VE. Para VR, a coleta manual se apresentou como a t?cnica mais apropriada para registrar sua riqueza. No entanto, as armadilhas de queda (na VE) e as iscas (na VR) registraram uma parcela n?o t?o desprez?vel da riqueza. Em nossos dados, as coletas manuais foram associadas a protocolos de coleta padronizados, e, apesar de serem bastante criticadas, mostraram efici?ncia no registro de esp?cies em habitats em que outras t?cnicas mais difundidas n?o podem ser utilizadas. Apesar de fisionomias distintas apresentarem efici?ncia de t?cnica de coleta diferenciada, ? relevante a utiliza??o das tr?s t?cnicas para se potencializar ainda mais o registro das esp?cies em ambientes de campos de altitude.
222

História natural de Centris (Paracentris) burgdorfi Friese, 1901 (Apidae, Centridini) / Natural history of Centris (Paracentris) burgdorfi Friese, 1901 (Apidae, Centridini)

Sabino, William de Oliveira 11 July 2017 (has links)
Na presente tese estudei a biologia de Centris (Paracentris) burgdorfi, uma abelha solitária de ampla distribuição no Brasil. O único local de nidificação conhecido até o momento fica em uma área de dunas, no nordeste do Brasil, à 25 km da cidade de Natal. Neste local as fêmeas nidificam exclusivamente em paleodunas à cerca de 1 km do mar. Estudei o sistema de acasalamento da espécie, onde pude constatar que a alta competição por fêmeas próxima ao ninho faz com que o macho tenha que retirar a fêmea do local para conseguir o contato genital. Nenhuma fêmea foi vista acasalando mais de uma vez e, logo após a cópula a fêmea dá início à construção do ninho. O ninho é constituído de um túnel raso com acesso às células de cria, construídas uma ao lado da outra. Avaliei o número de viagens que a fêmea faz para a coleta de óleo e pólen e o tempo despendido em cada ação dentro do ninho (deposição de pólen, óleo, ovoposição e operculação). Durante o período de construção das células as fêmeas não dormem dentro do ninho, e sim, em ramos de Krameria tomentosa, a planta utilizada como fonte de óleo no local. Buscando ampliar nosso conhecimento sobre a espécie, procurei outras populações no Brasil para que pudesse avaliar o nicho trófico. Utilizei o pólen encontrado no corpo das fêmeas para inferir sobre a dieta parcial de adultos e imaturos. Além da área de dunas, no Nordeste, encontramos C. burgdorfi no cerrado em Cavalcante, Goiás e em áreas de campo de altitude, em Ponta Grossa, Paraná. Através da análise polínica, constatei a importância de plantas do gênero Chamaecrista como fonte de pólen, sendo este um dos poucos gêneros compartilhados entre os três locais. Krameria grandiflora foi a fonte de óleo em Cavalcante e em Natal, e Angelonia integérrima, foi a fonte de óleo no Paraná. Isso revela a amplitude de nicho trófico em C. burgdorfi não apenas em relação às espécies de plantas utilizadas na dieta mas, também, quanto ao tipo de elaióforo que a fêmea consegue acessar (epitelial e tricromático). Esta plasticidade possibilita a ampla distribuição da espécie em diferentes fitofisionomias. Analisei nutricionalmente a dieta na provisão da cria de C. burgdorfi do nordeste do Brasil e de células de cria de Centris (Paracentris) pallida, coletadas no sudoeste dos Estados Unidos. Centris pallida é uma espécie de Centridini que perdeu o comportamento da coleta de óleo. Centris burgdorfi possui uma dieta mais rica em lipídeos e proteínas, sendo a dieta de C. pallida mais rica em carboidratos. A dieta mais protéica de C. burgdorfi se deve à presença de Chamaecrista já que plantas que anteras poricidas contem mais proteínas em comparação às não-poricidas, como é o caso das fontes de pólen de C. pallida (Parkinsonia e Olneya) / In the present thesis, I studied the biology of Centris (Paracentris) burgdorfi, a solitary bee of wide distribution in Brazil. The only nesting site known is in a dune area in northeastern Brazil, 25 km from the city of Natal. In this place, the females nest exclusively in petrified dunes about 1 km from the sea. I studied the mating system of the species, where I could verify that the high competition by females near the nest forces the male to carry the female to another place to mate. No female was seen mating more than once and, soon after copulation, the female begins to construct the nest. The nest consists of a shallow tunnel with access to the brood cells. I evaluated the number of trips that the female made to the collection of oil and pollen and the time spent in each action within the nest (depositions of pollen, oil, oviposition and operculation). During the period of construction of the cells the females do not sleep inside the nest, but in branches of Krameria tomentosa, the plant used as source of oil. In order to increase our knowledge about the species, I searched for other populations in Brazil so that I could evaluate the trophic niche. I used pollen found in the body of females to infer about the partial diet of adults and immature. In addition to the dune area in the Northeast, I found C. burgdorfi in the tropical Savanna (Cerrado) in Cavalcante, state of Goiás and in high altitude field areas, in Ponta Grossa, state of Paraná. Through pollen analysis, I verified the importance of plants of the genus Chamaecrista as a source of pollen, being this one of the few genera shared among the three sites. Krameria grandiflora was the source of oil in Cavalcante and in the Natal, and Angelonia integerrima, was the source of oil in the Ponta Grossa. This reveals the trophic niche amplitude in C. burgdorfi not only in relation to the species of plants used in the diet, but also to the type of elaiophore that the female can access (epithelial and trichromatic). This plasticity makes possible the wide distribution of the species in different phytophysiognomies. Nutritionally I analyzed the diet in the provision of C. burgdorfi offspring from northeastern Brazil and from the breeding cells of Centris (Paracentris) pallida collected in the southwestern United States. Centris pallida is a species of Centridini that has lost the behavior of the oil-collection. Centris burgdorfi has a diet richer in lipids and proteins, and the diet of C. pallida is richer in carbohydrates. The most proteinic diet of C. burgdorfi is due to the presence of Chamaecrista, since plants with poricidal anthers contain more proteins compared to non-poricidal ones, such as C. pallida (Parkinsonia and Olneya) pollen sources
223

行政調查制度之研究 / The Legal System of the Administrative Investigation

洪文玲, Hung Wen-Ling Unknown Date (has links)
現代政府分工細密,專業機關依賴資訊制定推行決策之法令,作成具體決定,並確保政策被確實遵行。隨著網路科技的發達,資訊流通更為迅速,資訊載體樣態複雜,速度、效率、自由、開放的新價值觀,在在衝擊傳統調查方法與法律制度之內容。 本論文旨在建構既符合法治原理與人權保障要求,又能契合時代脈動具前瞻性之行政調查制度,故從行政調查之概念界定,繼而探討其傳統面貌以鑑往知來,再進行比較法制之觀察作為借鏡,進而探討未來行政調查制度內容之各種問題,分別從調查權之法源依據、調查主體與被調查者之關係、各種調查手段應遵行之正當程序、對調查瑕疵之各種救濟可能等層面逐一討論之。 第一章 緒論 第二章 行政調查概念之形成與界定 第三章 各國行政調查制度之比較觀察 第四章 行政調查之法源依據 第五章 行政調查主體與客體之關係 第六章 行政調查方法與正當程序 第七章 行政調查之監督與救濟 第八章 結論 / Modern governments rely on the expertise of agencies. Those agencies need to collect and use information. They need information to make the rules necessary to implement and assess the execution of the policy and ensure compliance with the policy. With the advancement of information technical, the rapidity of network communication, complexity of information loader, the speedy, efficient, free and open values do have great impacts on the traditional investigative methods and legal system. This paper aims at constituting the legal system on collecting information, which conforms to the principle of the rule of law and protection individual rights. There are several focal issues in this paper, such as the legal basis of investigative power, the relationship between agency and individual, the due process of various collecting methods, the remedies and compensation of wrongdoings etc.
224

Node-Weighted Prize Collecting Steiner Tree and Applications

Sadeghian Sadeghabad, Sina January 2013 (has links)
The Steiner Tree problem has appeared in the Karp's list of the first 21 NP-hard problems and is well known as one of the most fundamental problems in Network Design area. We study the Node-Weighted version of the Prize Collecting Steiner Tree problem. In this problem, we are given a simple graph with a cost and penalty value associated with each node. Our goal is to find a subtree T of the graph minimizing the cost of the nodes in T plus penalty of the nodes not in T. By a reduction from set cover problem it can be easily shown that the problem cannot be approximated in polynomial time within factor of (1-o(1))ln n unless NP has quasi-polynomial time algorithms, where n is the number of vertices of the graph. Moss and Rabani claimed an O(log n)-approximation algorithm for the problem using a Primal-Dual approach in their STOC'01 paper \cite{moss2001}. We show that their algorithm is incorrect by providing a counter example in which there is an O(n) gap between the dual solution constructed by their algorithm and the optimal solution. Further, evidence is given that their algorithm probably does not have a simple fix. We propose a new algorithm which is more involved and introduces novel ideas in primal dual approach for network design problems. Also, our algorithm is a Lagrangian Multiplier Preserving algorithm and we show how this property can be utilized to design an O(log n)-approximation algorithm for the Node-Weighted Quota Steiner Tree problem using the Lagrangian Relaxation method. We also show an application of the Node Weighted Quota Steiner Tree problem in designing algorithm with better approximation factor for Technology Diffusion problem, a problem proposed by Goldberg and Liu in \cite{goldberg2012} (SODA 2013). In Technology Diffusion, we are given a graph G and a threshold θ(v) associated with each vertex v and we are seeking a set of initial nodes called the seed set. Technology Diffusion is a dynamic process defined over time in which each vertex is either active or inactive. The vertices in the seed set are initially activated and each other vertex v gets activated whenever there are at least θ(v) active nodes connected to v through other active nodes. The Technology Diffusion problem asks to find the minimum seed set activating all nodes. Goldberg and Liu gave an O(rllog n)-approximation algorithm for the problem where r and l are the diameter of G and the number of distinct threshold values, respectively. We improve the approximation factor to O(min{r,l}log n) by establishing a close connection between the problem and the Node Weighted Quota Steiner Tree problem.
225

the Wanderer

2013 January 1900 (has links)
A reflective essay to accompany the thesis exhibition, the Wanderer, installed in the Gordon Snelgrove Gallery, 2013. An exploration of the questions and concepts informing the process of developing and refining the visual vocabulary of my practice. Images of women, topographical maps, floral imagery and astronomical maps provide the vocabulary of the language and syntax that I am developing to enunciate the interrelationships between the construction of self and lived experience, with concepts of identity, body and gesture, history and place.
226

Miquel Mai (ca. 1480-1546). Art i cultura a la cort de Carles V

Bellsolell Martínez, Joan 12 July 2011 (has links)
The doctoral thesis was an study about Miquel Mai, a polític, jurist, bibliophile and art collector in Barcelona in the first half of the XVI century. The thesis presents the figure of Miquel Mai by his biographic history, with emphasis in the principals chapters that he was participant. After, there was a chapter whose principal theme its the connection between Miquel Mai and the Erasmism movement. Third, it was an analysis of all the art objects that Miquel Mai accumulates. Fourth, the thesis explores the library (formed by more than 2000 books). And finally, we studied the relationship between the art objects who decorate the library and the same books that was in the library. / Aquesta tesi és un estudi al voltant de la persona de Miquel Mai, politic, jurista, bibliòfil i col•leccionista d'art a la Barcelona de la primera meitat del segle XVI. La tesi presenta a Miquel Mai a partir del seu relat biogràfic, posant especial èmfasi en els principals capítols polítics en els que va participar. Seguidament es desenvolupa un capítol dedicat a la possible definició de Miquel Mai com a erasmista i la influència que aquest corrent espiritual va jugar al llarg de la seva vida. En tercer lloc s’analitza els inventaris de béns i tota la relació d’objectes artístics que va acumular amb el pas del temps. Un quart aspecte gira entorn a l’extensa biblioteca (més de 2000 llibres) que Miquel Mai va formar a la seva residència de la plaça de la Cucurulla de Barcelona. I en cinquè lloc es posa de manifest la relació directe entre els béns artístics que decoraven la biblioteca i les lectures que precisament es trobaven en aquesta biblioteca.
227

The Study on Management of Financial Problems among Taiwan Travel Industry

Chang, King-Ming 26 June 2012 (has links)
Operation scales of the travel agencies can be giant or tiny in term of sizes. No matter in Taiwan or abroad, most trvel agents are SMEs (small and medium enterprises), while some large-scale foreign or mainland travel agencies are even bigger than ordinary banks or airlines. Travel agents play a role as an important channel for travelers. They collect a considerable huge amount of money from travelers and pay to the suppliers just like a temporary God of Wealth. Airline tickets and tour fares end up to some hundred millions or even some billions of turn over (in total amount counting method) commonly. This is an industry which charges in advance before providing services. In addition to the shorter term of airline credit, six elements of travel - meals, accommodations, transportations, sightseeing, shopping, and entertainments, are allowed routinely credited periodically, especially tours fares often accumulated to an astronomical figures. This sevice industry is quite different from other manufacture suffered from the "inventories" problem, but with something in common, it has a huge amount of outstanding accounts remain unsettled, or even worse to cause the phoenomenon of financial black hole with "assets virtually inflated and liabilities virtually reduced". Several large tours wholesalers in Taiwan went bankruptcy might be owing to these reasons. Even the subsidiary of TUI, the world's largest tours group, outbroke similar news incident in early 2011. It was not singly but in pairs, Reuters reported that Europe's second largest travel company Thomas Cook facing financial crisis in late 2011, were forced to acquire ¢G 2 billion loan from banks to survive in the coming low winter season. A great amount of accumulated money often causes a crisis of credit expansion, if any ambitious entrepreneur seeks to gain more profits from other reinvestments, intends to get real estates, accquitions, mergers, and other risky investments, possibly resulted in large scale damage with both investments and foreign currency exchange losses, when facing an economy downturn or political turmoils. "Financial management" is always the primary course of business running. Emphasis on the "financial problems management" is not just a slogon, and not just to watch bank deposits closely, but also to realize how and what sholuld be seriously paid attention to. Revenue increasing and cost cutting are always the true value of financial management on business development. The differences of corporate finance from time to time are as same as different figures of human pulse, blood presure, or blood suguar that varies at diffent times or in different conditions. Financial management of a company is just like personal health management, such as people in different stages faces different situations and needs. So companies must grasp the pulse of business development in different stages to plan for the future direction. Many companies seek to maximize profits at the same time, yet ignoring the strong managing and decision-guiding functions of financial management. Newspapers and magazines often report how many employees and consumers are impacted by the closing of plants or travel agencies, many of them are wellknown enterprises. Although the global economic downturns, the failure of business diversification or reinvestment hold-up losses and other factors might take the blames. But as the old saying: "There is no sunset industry but only sunset enterprises." How to survive in the harsh environment? We must strengthen to master financial management, through analysis and control of "financial problems management" to generate necessary resources and to cut the costs to enhance the business performance. "The management of financial problems among travel industry" is really the weakest point of this industry. Practical financial management books or informations for travel agencies are not easy to be found in stores or other resources. In past decades we have seen the rotation of rises and falls in the industry, we strongly believe "Accounting and Financial Management" is the basis for all kinds of management. This thesis contains the examples of Phoenix Tours International and other travel agents among Taiwan travel industry. The real experiences of daily practices are the most important contents. I attempt to integrate academic theories into daily practices, a little theoretical but more practical argument, to provide better healthy informations for the industry. Despite the company accounting system, I had also tried to establish a basic financial training material for my management team. Wish all our colleagues will not repeat the same financial errors of their predecessors. Under the guideline of Taiwan Tourism Bureau which is committed to developing tourism with ¡§Vanguard for excellences and piloting for all projects¡¨, I tried to do my best to write down personal experiences and researches knowledge as basic works. Hope to bring up some echoes and brainstormings, to lead a brighter future and better progress for the industry. All the appendixes to this thesis are important references to the main text. Many of them are also my writings in the past. At last, IFRSs regulations will soon be implemented, we have to find out its impacts on the enterprises that should not be underestimated. Not only affect financial and accounting areas, information system, performance reward systems, investor relations, tax and legal aspects will also have significant impacts. IFRSs conversion or convergence may not only be an easy task, but provides an excellent opportunity for companies to re-examine the existing financial strategies, accounting policies, management systems, process efficiencies, risk managements, internal controls, system functions, corporate governances and investor relations practices, such as whether to meet current and future needs, and take this opportunity to enhance their strengths by improving inadequacies.
228

從主題檔案館功能探討我國軍事檔案館設置之必要性 / A Necessity study on the Establishment of Military Archives as base on the Functionality of Collecting Archives

熊蒂生, Shiung, Ti-Sheng Unknown Date (has links)
主題檔案館是檔案館分類之一,具有檔案館基本屬性,因館藏內容特殊性及專業性,而有不同類型之主題檔案館;主題檔案館同時保存檔案與資料,致使檔案與資料一體化管理,形成主題檔案館最主要之特色。軍事檔案館屬於主題檔案類型,以軍事或戰爭資料為主要典藏對象,因其典藏媒體多樣化,且有許多實體武器之保存與展示,因此,軍事檔案館所使用名稱依據典藏資料特性而異。如:戰爭紀念館、國防檔案館、軍事博物館等,以文獻資產觀念而言,均屬於軍事檔案館之範疇。 本研究使用「文獻分析法」與「深度訪談法」進行研究,由文獻分析中探討法國、德國、英國、美國、澳洲、日本等國及我國國軍歷史文物館、海軍軍史館、空軍軍史館、八二三及古寧頭戰史館等軍事檔案館建置歷程、館藏及其組織架構與人力。 深度訪談對象包括國軍歷史文物館、海軍軍史館、空軍軍史館、八二三及古寧頭戰史館、國防部、檔案管理局等七個單位,藉以瞭解各相關單位對建置軍事檔案館之看法與意見。同時結合各國軍事檔案館建置、發展,及我國軍史館與戰史館現況,研擬我國建置軍事檔案館方案,以供未來建置規劃之參考。 本研究提出六點結論:一、設置軍事檔案館之必要性,主要有下列五點:(一)軍事檔案館典藏資料具有特殊性及專業性,以主題方式管理及應用,具有良好之效益;(二)就風險管理而言,可以分擔風險;(三)在政府組織再造之際,可避免組織架構重疊;(四)臺灣地理位置極具地緣戰略價值,國防軍事資料為國內及國際所重視;(五)配合檔案開放應用之規定,成立軍事檔案館不但可以確保資料安全,同時滿足檔案開放應用之需求;二、確立主題檔案館定位,以利後續發展;三、主題檔案館缺乏法源依據,檔案館組織、人員及預算編制法制化以利未來檔案館館務運作長期穩定發展;四、先進國家對特定檔案多設置主題檔案館,我國應朝向設立綜合性國家檔案館及主題性檔案館併行之發展;五、國防部檔案管理機制健全,在軟體方面已具有國防軍事主題檔案館之雛型;六、軍史館與戰史館具分別存在價值。 依據研究結果提出之建議:一、制定主題檔案館相關法源依據,以利未來檔案館館務正常運作之發展;二、軍事檔案館檔案屬於國家檔案,方能化解建置過程中可能遭遇之窒礙因素;三、建置國防檔案專責單位,統籌管理與執行國防檔案及軍事主題檔案館相關政策;四、主題檔案館應與休憩結合,提升民眾使用檔案之興趣,並提高軍事主題檔案館在國際之知名度。
229

Evolutionary ecology of Malpighiaceae pollination at the species and community levels

Cappellari, Simone Caroline 18 November 2013 (has links)
Plant-pollinator interactions figure as key elements promoting the natural regeneration of terrestrial vegetation, as most plants depend on animals to transfer their gametes between flowers and produce seeds. Bees are the most common pollinators of plants and their interactions with flowers have served as model systems for the study of specialized mutualisms since Darwin's time. While most plants offer nectar as a reward and attract a variety of floral visitors, others produce distinctive types of resources which are sought by particular groups of pollinators. Such associations may involve specialization at the morphological, behavioral, or physiological levels and are especially common in tropical habitats. The interactions between oil-producing flowers of Neotropical Malpighiaceae and oil-collecting bees are an example of a specialized mutualism in which plants offer lipids to attract pollinators that use the resource to build nest cells and feed their offspring. Although several studies have focused on specialized pollination at the species level, their effects on the organization of tropical communities remain largely unexplored. This dissertation aims to help fill this gap through an analysis of the mechanisms of pollinator partitioning in multi-species assemblages of specialists as well as a study of the organization of communities in which they occur. The motivation for pursuing the study of specialized interactions using Neotropical species of Malpighiaceae as a model system is outlined in the first chapter. In Chapter 2, I present an evaluation of the structural properties of a plant-pollinator community from the Cerrado, a seasonal ecosystem that hosts a large diversity of oil flowers. The third chapter analyzes pollinator partitioning and reproductive strategies promoting the coexistence of closely related Malpighiaceae. A possible outcome for the selective pressures imposed by the coexistence of specialists is presented in Chapter 4 by a case study providing evidence for a shift from specialized to generalized pollination in a Neotropical Malpighiaceae species. The last chapter includes reports of active floral oil foraging by males of Tetrapedia and a description of an oil storage structure without precedence among bees and unique to males of this genus suggesting that floral oils may also play a role in bees mating systems. / text
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Paprastosios eglės ir paprastosios pušies sėklų nusparninimo šlapiuoju būdu trukmės optimizavimas / Optimization of wet dewinging time of Scots pine and Norway spruce seeds

Petraitis, Tomas 14 January 2009 (has links)
Tyrimų pagrindimas. Dubravos eksperimentinės mokomosios miškų urėdijos įsigyto šlapio sėklų nusparninimo įrenginio „Nomeco Dewinger B1086” naudojimo instrukcijoje nėra nurodytas optimalus paprastosios pušies ir paprastosios eglės sėklų nusparninimo laikas. Tam, kad optimizuoti šlapio nusparninimo laiką aukščiau minėtame įrenginyje reikalingi tyrimai kaip sėklų nusparninimo kokybė priklauso nuo nusparninimo trukmės. Tyrimo tikslas buvo nustatyti optimalią paprastosios pušies ir paprastosios eglės sėklų nusparninimo trukmę šlapiojo nusparninimo metodu įrenginyje „Nomeco Dewinger B1086”. Tyrimo uždaviniai: (1) atlikti 15, 30, 45, 60 ir 120 minučių trukmės paprastosios pušies ir paprastosios eglės sėklų nusparninimo testus sėklų nusparninimo įrenginyje „Nomeco Dewinger B1086”, kiekvienai rūšiai naudojant tris skirtingas sėklų siuntas, (2) nustatyti paprastosios eglės ir paprastosios pušies sėklų nusparninimo kokybę priklausomai nuo sėklų nusparninimo trukmės. Tyrimo objektas yra sėklų nusparninimo kokybės testai, atlikti sėklų šlapiojo nusparninimo principu veikiančiame nusparninimo įrenginyje „Nomeco Dewinger B1086”. Tyrimo metodai. Kiekvienam iš 15, 30, 45, 60 ir 120 minučių trukmės nusparninimo bandymų buvo naudotos 3 skirtingos paprastosios eglės ir 3 skirtingos paprastosios pušies sėklų siuntos. Kiekvienam tam tikros trukmės ir sėklų siuntos testui buvo analizuoti 4 sėklų bandiniai po 100 sėklų. Viso buvo įvertinta 12 000 sėklų nusparninimo kokybė. Tai rodo aukštą gautų... [toliau žr. visą tekstą] / The Essence of Master Thesis: Dubrava experimental and teaching forestry owns „Nomeco Dewinger B1086” which is a dewinger for the wet seedlots. However, in its manual, there is no indication how much time it takes to dewing the seeds of pine and spruce. In order to optimize the time of the wet dewinging it is necessary to explore whether the quality of dewinging is influenced by the period of time that the process of dewinging takes. The main aim of the research is to determine the optimal time that a method of a wet dewinging takes with „Nomeco Dewinger B1086”. The Tasks of the Thesis. To perform 15, 30, 45, 60, and 120 min long dewinging tests for the seeds of pine and spruce with a dewinger for the wet seedlots „Nomeco Dewinger B1086”, using three different kinds of seeds of each tree. To detect the quality of dewinging of a pine and a spruce depending on the time the process takes. The objects of the thesis are the tests of the seeds dewinging, carried out with the device „Nomeco Dewinger B1086”. The methods of the Thesis. In each of 15, 30, 45, 60, and 120 minutes long tests of dewinging were used three different kinds seeds of pine and spruce. For each of the time period test were used four samples of the seeds, each consisting of one hundred seeds. All in all, there were 12 000 seeds that were evaluated. It shows great reliability of the research. The quality of the seeds dewinging were classified into four main categories. The data that was achieved during the... [to full text]

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