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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.
61

Comportamento reprodutivo do tangará-dançarino, Chiroxiphia Caudata (aves Pipridae) em uma área de Mata Atlântica / Breeding behavior of the Atlantic Forest-endemic Blue-Manakin, Chiroxiphia caudade (Aves, Pipridae)

Zima, Paulo Victor Queijo 04 February 2015 (has links)
Submitted by Milena Rubi (milenarubi@ufscar.br) on 2017-03-08T17:34:07Z No. of bitstreams: 1 ZIMA_Paulo Victor Queijo_2015.pdf: 8634156 bytes, checksum: 4f2f88f4f14eb30e6ad14457045ce5d8 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-03-08T17:34:16Z (GMT) No. of bitstreams: 1 ZIMA_Paulo Victor Queijo_2015.pdf: 8634156 bytes, checksum: 4f2f88f4f14eb30e6ad14457045ce5d8 (MD5) / Approved for entry into archive by Milena Rubi (milenarubi@ufscar.br) on 2017-03-08T17:35:00Z (GMT) No. of bitstreams: 1 ZIMA_Paulo Victor Queijo_2015.pdf: 8634156 bytes, checksum: 4f2f88f4f14eb30e6ad14457045ce5d8 (MD5) / Made available in DSpace on 2017-03-08T17:35:07Z (GMT). No. of bitstreams: 1 ZIMA_Paulo Victor Queijo_2015.pdf: 8634156 bytes, checksum: 4f2f88f4f14eb30e6ad14457045ce5d8 (MD5) Previous issue date: 2015-02-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / The family Pipridae is endemic to the Neotropics, having frugivorous habits. Males of some species make complex sexual displays to attract the females, and they live in the middle stratum of tropical forests. Of 51 species, 29 have their nests described, five have incubation periods descriptions, and six have nestling periods reported. The Blue Manakin, Chiroxiphia caudata, is common in humid and secondary forests of southeastern Brazil, northeastern Argentina and eastern Paraguay and its breeding biology is poorly documented. Here analyzed 36 active nests in two breeding seasons (2013/2014 and 2014/2015) in a well-preserved Brazilian Atlantic Forest continuum. Nests were swallow cups hung by their rims in horizontal forks, built in bushes or saplings, over or near forest streams. Reproductive activities were recorded from October to February and clutch sizes were invariably two eggs. Incubation period was 18 days, and nestling period was 15 - 16 days. Estimated overall nesting success, from egg-laying to fledging, was 40%, being higher than most studies on piprids that have been conducted in disturbed habitats. Our data give support to the theory that in the Pipridae family only females provide parental care. / Não informado pelo autor.
62

Determining The Impacts Of Beach Restoration On Loggerhead (caretta Caretta) And Green Turtle (chelonia Mydas) Nesting Patterns And Reproductive Success Along Florida's Atlantic Coast

Hays, Allison Whitney 01 January 2012 (has links)
Artificial beach nourishment, the most common method to mitigate coastal erosion in the United States, is also considered the most ecologically friendly alternative for shoreline stabilization. However, this habitat alteration has the potential to impact nesting marine turtles and developing hatchlings. The first objective of this study was to determine how nourishing beaches with two different design templates affects loggerhead (Caretta caretta) and green turtle (Chelonia mydas) nesting success, the ratio of nests to the total number of nests and non-nesting emergences, and reproductive success, the ratio of hatched and emerged hatchlings to the total number of eggs deposited. Two types of restoration designs exist along the southern Brevard County, FL coastline, which supports some of the highest density loggerhead and green turtle nesting worldwide. Since 2005, approximately 35 kilometers of beach have undergone 1) fullscale restoration (typically called nourishment), where sand was added above and below the mean high tide line (2005, 2010) or 2) dune restoration, where sand was placed on the dune (2005, 2006, 2008, 2009). To quantify the effects of these restoration types, we used a Before-After-ControlImpact-Paired Series (BACIPS) model, which tests for significance between the difference in nesting success rates at the impact (engineered) and control sites (natural beach) before and after restoration ( ). For loggerheads, there was a significant difference in after dune restoration during the years of construction (2005, 2006, 2008, and 2009; p
63

The Tenants of Apple Orchards: Evaluating the Effects of Additional Nesting Habitat on Bee Populations

Hyjazie, Batoule 29 September 2022 (has links)
Identifying the resources that limit bee populations is essential both for bee conservation and pollination management in agroecosystems. Land-use change typically leads to decreased habitat availability for wild pollinators including loss of nesting habitat, which is an essential but often-overlooked resource for wild bees. Cavity-nesting bees, such as many Osmia spp. (Hymenoptera: Megachilidae), occupy holes in wood or reeds to build their nests; due to their nesting habits, they are frequently scarce in agricultural settings, although, under the right circumstances, these bees can be ideal pollinators of apple and other orchard crops. Artificial nesting structures (“bee hotels”, “trap nests”, or “nest boxes”) are used to study cavity-nesting bees and have been posited as solutions for promoting bee conservation. To evaluate the effects of additional nesting habitat on the local abundance of Osmia spp., and on bees more generally, artificial nesting structures for cavity-nesting bees were installed at 24 sites in apple orchards around Ottawa in 2021 and 2022. Each site had two treatments: one with nest boxes, and one without (control). Transect walks were conducted to measure overall bee contact (including contact by Osmia spp.) with apple blossoms and, after the end of apple bloom, with flowers in the undergrowth and/or in shrubs. Numbers of apple buds and developing fruit were also recorded. Osmia spp. and overall bee numbers were both significantly higher in the treatment with nest boxes (44% and 15% higher, respectively, in 2021, and 113% and 47% higher, respectively, in 2022); however, there was no difference in fruit set (apple count/bud count) between the two treatments. Thus, nest boxes seem to locally increase Osmia spp. numbers as well as total bee numbers, but they have no apparent effect on apple yield, likely because apple production was not pollinator limited in the years of this study. These findings suggest that bee populations in apple orchards are limited by nesting resources, which has important implications for orchard management practices and bee conservation policy.
64

Sexual Dimorphism in a Joint-Nesting Plural Breeder, the Smooth-Billed Ani (Crotophaga ani) / Sexual Dimorphism in Smooth-Billed Anis / Sexual Selection in a Joint-Nesting Plural Breeder, the Smooth-Billed Ani (Crotophaga ani)

Barclay, Megan 09 1900 (has links)
Sexual selection has been investigated in many different systems but information is lacking in joint-nesting species. Both sexual dimorphism and possible signals of quality were explored in this study for a joint-nesting plural breeder, the smooth-billed ani (Crotophaga ani). Sexual dimorphism can be examined for a species in an attempt to reveal particular traits that might be under sexual selection and the strength of sexual selection on them. In mate choice decisions, sexually selected traits may be used by the choosy individual to assess the quality of potential mates. These honest traits need to reveal the condition and genetic quality of the individual accurately. For example, it has been proposed that plumage colour reveals condition, and more specifically parasite resistance in birds. This study explores sexual size dimorphism and dichromatism in smooth-billed anis, as well as the ability of their feather colour to reveal body condition (measured as residuals from a regression of mass versus body size), body size, and parasite numbers. Additionally, because anis are group living birds, this study investigated whether group size had an effect on parasite numbers. Anis from a population in southwestern Puerto Rico were measured for size, their feathers were collected and analyzed using a spectrometer, and ectoparasites were collected by dustruffling. For all size traits measured, males were significantly larger than females. Males also had more exaggerated bill depths (relative to body size) than females. There were no differences between the sexes for all colour morphometries, except tail saturation; females had more saturated tails than males. While no decisive conclusions can be drawn as to why the dimorphic traits are different between males and females, sexual selection may have played a role. The relationship between log10 average lice numbers per group and group size was positive, but not significant. In male smooth-billed anis, plumage colour was not related to lice or mite numbers, or body size and body condition. Plumage colour was also not related to body condition and size in females. Additionally, ectoparasites did not have an effect on male body condition. Plumage may not only be an inaccurate signal of parasite resistance or body size and body condition in the smooth-billed ani, but ectoparasites may not even have a negative effect on their host. The inability to find significant results may have been affected by other factors, such as feather wear and the age of individuals. These results warrant a more detailed look into the social behaviour of the group-living smooth-billed ani. / Thesis / Master of Science (MSc)
65

Reproductive ecology of Rio Grande wild turkey in the Edwards Plateau of Texas

Melton, Kyle Brady 15 May 2009 (has links)
The abundance of Rio Grande wild turkeys (Meleagris gallopavo intermedia) in the southeastern Edwards Plateau of Texas has declined since the late 1970s. Because knowledge of reproductive rates is important to understanding the dynamics of a population, radio-tagged hens were monitored during the 2005–2007 reproductive seasons to evaluate and compare reproductive parameters from areas with both declining and stable population trends. During January–March of 2005–2007, turkey hens were captured and radiotagged on 4 study areas; 2 within a region of stable turkey populations, and 2 within a region of declining populations. Monitoring occurred from January–July each season to determine nest- site locations. Nesting attempts, nest fate, clutch size, initiation date, and nest age were recorded. Nests were monitored ≥3 times weekly in order to estimate production parameters and daily nest survival. Poults were captured by hand and fitted with a 1.2 glue-on transmitter and monitored daily to estimate daily survival. Estimates show production was greater in stable regions than declining regions of the Edwards Plateau. Eighty-four percent of hens attempted to nest in the stable region and 67% attempted in the declining region. Eighteen of 102 nests were successful (≥1 egg hatched), in the stable region and 7 of 60 nests were successful in the declining region. Nest-survival analysis showed an influence of temporal variation within years, yet no differences in nest survival were detected between stable and declining regions. Poult survival also showed no difference between regions. The 2 overall objectives of this study were to determine if nesting parameters and nest survival were limiting factors in Rio Grande wild turkey abundance in the Edwards Plateau. Regional differences in production suggest the cause of the decline in the southeastern portion of the Edwards Plateau could be associated with lower reproductive output and consequently, success. Regional differences in nest survival were not detected, thus not likely to cause differences in turkey abundance between regions.
66

Influ?ncia do comprimento do ninho-armadilha na sele??o das cavidades para nidifica??o, na mortalidade da prole e na raz?o sexual de abelhas solit?rias (Hymenoptera: Apidae)

Santos, Claudia Oliveira dos 26 March 2013 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-03-01T00:40:16Z No. of bitstreams: 1 DISSERTA??O Claudia.pdf: 581878 bytes, checksum: 64bfb898fa3dfecf415c1fe65fad5fbf (MD5) / Made available in DSpace on 2016-03-01T00:40:16Z (GMT). No. of bitstreams: 1 DISSERTA??O Claudia.pdf: 581878 bytes, checksum: 64bfb898fa3dfecf415c1fe65fad5fbf (MD5) Previous issue date: 2013-03-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / This study aimed to investigate the acceptance of cavities with different lengths for nesting and the cavity size effects on the sex ratio and offspring mortality of solitary bees in two agricultural areas in Feira de Santana, Brazil. The samplings were carried out monthly, during 12 months, using trap-nesting (=NA) length 5, 10, 15 and 20 cm. A total of 124 nests, 591 building cells, and 479 emerging imago were sampled. There was a higher number of nesting in area I (n=86) than in area II (n=38). Centris analis Fabricius 1804, Centris tarsata Smith, 1874, and two Megachile species nested in ?rea I, being C. analis the specie with highest number of established nest (n=72, 83.7%), while other species had low nesting frequency (4%) and a higher bee richness, with six species occupying the trap-nesting. Tetrapedia diversipes Klug, 1810, established highest number of nest (n=29, 76.3%). Species used different NA size in both areas. In the area I, they nesting with higher frequency in NA with 10 cm (38%) and 15 cm (38%), while in the area II, there was cavity occupation with 20 cm (50%). Bees nested in most part of the year, except in months of autumn-winter, between April and August, when the bee nesting frequency was reduced or the activity was suspended. The natural enemies that emerged from the nests were species of Hymenoptera Coelioxoides sp, Mesocheira bicolor Fabricius, 1804, and a species of Chrysididae. The mortality rate by unknown reason in the areas I and II was 21.4% and 13.5% respectively, with higher incidence recorded to Centris analis. There was a higher mortality in smallest nests (5 cm) and there was no difference among the cavities with 10, 15, and 20 cm. / Este trabalho teve como objetivo investigar a utiliza??o de cavidades de diferentes comprimentos para confec??o de ninhos e os efeitos do tamanho da cavidade sobre a raz?o sexual e mortalidade da prole de abelhas solit?rias. O estudo foi conduzido em duas ?reas agr?colas no munic?pio de Feira de Santana, Bahia. Foram realizadas amostragens mensais durante 12 meses, usando ninhos-armadilha (NA) de comprimento 5, 10, 15 e 20 cm. Foram obtidos 124 ninhos, 591 c?lulas de cria constru?das e 479 imagos emergentes. Houve maior n?mero de nidifica??es na ?rea I (n=86) do que na ?rea II (n= 38). Centris analis Fabricius 1804, Centris tarsata Smith, 1874 e duas esp?cies de Megachile nidificaram na ?rea I, sendo C. analis a esp?cie com maior n?mero de ninhos estabelecidos (n=72, 83,7%), enquanto as outras esp?cies tiveram baixa freq??ncia de nidifica??o. A ?rea II apresentou menor freq??ncia de nidifica??o (4%) e maior riqueza de abelhas, com seis esp?cies ocupando os ninhos-armadilha. Tetrapedia diversipes Klug, 1810, estabeleceu maior n?mero de ninhos (n=29, 76,3%). As esp?cies utilizaram diferentemente os tamanhos de NA nas duas ?reas. Na ?rea I, as abelhas nidificaram com maior freq??ncia nos NA de 10 cm (38%) e de 15 cm (38%), enquanto na ?rea II houve maior ocupa??o das cavidades de 20 cm (50%). As abelhas nidificaram na maior parte do ano, com exce??o dos meses de outono-inverno, entre abril e agosto, quando a frequ?ncia de nidifica??o das abelhas foi reduzida ou a atividade foi suspensa. Os inimigos naturais que emergiram dos ninhos inclu?ram esp?cies de abelhas Coelioxoides sp, Mesocheira bicolor Fabricius, 1804 e uma esp?cie de Chrysididae. A taxa de mortalidade por causas desconhecidas nas ?reas I e II foi respectivamente 21,4% e 13,5%, com maior incid?ncia registrada em Centris analis. Houve uma maior mortalidade nos ninhos curtos (5 cm), n?o havendo diferen?a entre as cavidades de 10, 15 e 20 cm.
67

Intelligentes Nesting in der Kreislaufwirtschaft zur Steigerung der Ressourceneffizienz

Kronenberg, Philipp, Wieck, Franz, Weber, Sebastian, Löwer, Manuel 09 September 2021 (has links)
Kreislaufwirtschaft ist ein Konzept, um den Rohstoff- und Ressourcenverbrauch wirksam zu reduzieren. Hierbei sollen bestehende Produkte und Ressourcen so lange wie möglich in wertschöpfenden Kreisläufen gehalten werden. Im Rahmen der Repurpose (Wiederverwendung) Strategie werden Bauteile und Ressourcen von ausrangierten Produkten in neue Produkte mit anderer Funktion wiederverwendet. Hierzu müssen Rohlinge für neue Produkte in Sekundärrohstoffen angeordnet und herausgetrennt werden. Bedingt durch den nicht standardisierten Zustand von Sekundärrohstoffen, wird ein intelligentes Nesting Verfahren eingesetzt, die Ressourceneffizienz zu verbessern. Der Einsatz von intelligentem Nesting im Rahmen der Kreislaufwirtschaft zeigt, dass der Einsatz von Sekundärrohstoffen gesteigert und die benötigte Energie für die nachfolgenden Fertigungsverfahren eingespart werden kann.
68

Effektivisering av tillverkningsprocess med mjukvara för nesting / Effectivizing a manufacturing process with nesting software

Lundgren Akbarzadeh, André January 2023 (has links)
Rapporten presenterar ett examensarbete vid Kungliga Tekniska Högskolan, utfört på ett företag i skylttillverkningsindustrin. Syftet med examensarbetet är att undersöka om produktionen på det uppdragsgivande företaget kan effektiviseras genom att ersätta ett manuellt arbetsmoment med en automatiserad lösning i form av en mjukvara. Det undersöks även om, och i sådant fall hur stora förbättringar som kan göras i processen sett till ekonomisk, ekologisk och social hållbarhet. Genom att undersöka marknadens utbud av mjukvaror för nesting och jämföra mjukvarornas egenskaper mot definierade krav kunde en handfull mjukvaror konstateras vara relevanta. Testprogramvaror begärdes för dessa, och i de fall de erhölls så testades mjukvarorna på rådata från projekt som företaget tidigare tillverkat i syfte att jämföra resultaten. Skillnaderna i resultat beräknades och jämfördes med resultaten av det manuella arbetssättet. Det konstaterades att användning av den bäst presterande mjukvaran kan spara företaget i snitt 481 kronor per projekt i minskad material- och tidsåtgång. Vidare beräknades att företaget hade kunnat spara drygt 28 kg material på de fem projekten som tillverkades i aluminium, för vilka bara återvinningen hade kostat ca 2,25 kg koldioxidekvivalenter per projekt. Nyproduktionen av denna aluminium uppskattas motsvara mellan 16,6 – 36,2 kg koldioxidekvivalenter per projekt. / This paper presents a bachelors thesis at the Royal Institute of Technology, performed at a company in the sign manufacturing industry. The aim of the thesis is to investigate if the production at the company can be made more effective by replacing a part of the process that requires manual work with an automated solution in the form of a software. It is also investigated whether changes in the process can result in improvements in economical, ecological and social sustainability, and in that case the greatness of the improvements. By conducting market research of nesting software and comparing the properties of the software to pre-determined requirements, a handful of different software were considered potentially applicable. Software for testing were requested for these, and tests were conducted with those that were obtained. The tests were conducted on raw data from previously manufactured projects at the company in order to compare the results. The differences in results were calculated and compared with those of the manual process. It was concluded that the top performing software could render the company an average of 481 kronor saved per project in terms of time saved and material usage. Furthermore, calculations showed that the company could have saved over 28 kg worth of material for the five projects where aluminium was used. For these projects, the recycling of the aluminium would be equivalent to 2,25 kg carbon dioxide equivalents per kg, per project. The production of new aluminium for these projects would equate to an estimated 16,6 – 36,2 kg carbon dioxide equivalents per kg, per project.
69

Bottom-Up Impacts of Grazing Disturbance on Ground-Nesting Bee Assemblages: Do They Dig It?

Collins, Shannon Marie 12 1900 (has links)
In my thesis, I examined impacts of nesting and floral resources on ground-nesting bee assemblages at nine ranch sites with differing grazing histories. Because ecological disturbances can strongly affect the availability of foraging and nesting resources over time, I also examined the impacts of grazing history on nesting and floral resources for ground-nesting bees. I sampled bee assemblages, a comprehensive array of vegetation and soil measures, and floral abundance and richness. I used these data to determine (1) the importance of different nesting habitat resources and livestock grazing history for ground-nesting bees and (2) how livestock grazing history influenced the availability of nesting and floral resources. I found that sites with sandier soils had greater abundance and richness of ground-nesting bees, and sites with less compacted soils had greater bee abundance. Contrary to many other studies, the availability of bare ground was not important for ground-nesting bee abundance or richness. Grazing history did not affect any measures of nesting or floral habitat, and had negligible effects on ground-nesting bee abundance, richness, and community composition. My results suggest that the availability of sandier or less compacted soils may be limiting for ground-nesting bee abundance or richness, especially in areas with predominately clay soil types. In this context, the availability of such nesting resources may be more limiting than floral resource availability. More research is necessary to tease apart the effects of different nesting and floral resources for bees, and how different grassland management types affect bees through those resources. My findings highlight the importance of considering nesting habitat resources in bee conservation and restoration efforts.
70

Leaf Venation Networks

Ronellenfitsch, Henrik Michael 15 February 2016 (has links)
No description available.

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