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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.
111

Paleoindian Mobility Ranges Predicted by the Distribution of Projectile Points Made of Upper Mercer and Flint Ridge Flint

Mullett, Amanda Nicole 29 September 2009 (has links)
No description available.
112

The decline of Fowler's Toad (Bufo fowleri) in southern Louisiana: molecular genetics, field experiments and landscape studies

Vogel, Laura Sanders 08 August 2007 (has links)
Two of the most pervasive threats to species biodiversity are invasive species and habitat loss and degradation. Invasive species are often relatively insensitive to disturbance and many expand their range into disturbed and fragmented habitats. This dissertation uses an interdisciplinary approach to investigate how anthropogenic habitat disturbance is precipitating a range expansion in an invasive toad species, Bufo nebulifer, which is driving a decline in its native congener, B. fowleri. I employed a remote sensing and GIS study using historical data to compare changes in the two species distributions and habitat changes, a molecular genetic study to identify interspecific hybrids and their potential effects on the parental species, and an experimental ecology study to look at the effects of competition and predation on the two species. The results of the landscape level analyses of species' distributional changes in different disturbance levels showed that both species' distributions have changed significantly. The distributions of the two species are inversely affected by habitat disturbance; the distribution of B. fowleri in highly degraded habitat has contracted while the expansion of B. nebulifer increased substantially. The molecular genetic study successfully demonstrated the use of nuclear and mitochondrial markers to identify cryptic hybrids and their maternal lineage. Three hybrids were detected using nuclear introns and a morphologically cryptic hybrid was identified using mitochondrial DNA as the progeny of a cross that was previously thought to be inviable. Although relatively few hybrids were currently found, the identification of a cryptic hybrid implies that the rate of historical hybridization may have been drastically underestimated. Ecological studies showed that competition with B. nebulifer tadpoles had a negative effect on both body size measures and survival to metamorphosis for B. fowleri tadpoles. The addition of predators to experiment did not favor the survival of B. fowleri over B. nebulifer. Bufo fowleri's inability to compete with its invasive congener could be a driving mechanism for the decline of B. fowleri and the expansion of B. nebulifer. The methods discussed in this dissertation offer promising and practical new approaches for evaluating and managing changes in the distribution of species of conservation concern.
113

The Impacts of Agriculture and Plantation Forestry in a Selection of Upper Catchments of the Strzelecki Ranges, Victoria

Mainville, Daniel Mark, daniel.mainville@dse.vic.gov.au January 2007 (has links)
The intensive nature of land uses in the Strzelecki Ranges poses significant threats to landscape values and water quality. A comprehensive catchment strategy was developed based on sustainability science concepts incorporating the careful management of landscape values, proper land management approaches, and government policy and legislative change to ensure that agriculture, forestry and other land uses become sustainable in this sensitive environment. The readily measurable water quality indicators of turbidity, flow, electrical conductivity, and water temperature were used to determine the impacts of the major land uses in the Strzeleckis. From a water quality perspective, there was a trend of decreasing water quality with increasing intensity in land management. However, from a total sediment load perspective, the forest area contributed the highest total sediment load due to higher volumes of steam flow suggesting that natural processes in the Strzeleckis may remain the principal mechanisms for sediment movement within the catchment. An incidental but significant finding was extensive bioturbation along the riparian zone of the plantation area, the extent of which was not observed in the other catchments. This finding suggested that bioturbation may have been the most significant contributor to poorer water quality flowing from in the plantation catchment. The project developed insights into the major environmental processes active in the upper catchment of the Morwell River. Understanding of the contributions to total sediment loads from natural erosional processes and bioturbation, findings related to the impacts on water quality from agricultural practices, and encountering negligible impacts from conservative timber harvesting practices demonstrate that catchment management approaches need to be tailored to achieve sustainability in land uses across the landscape. Key recommendations include the re-establishment and protection of riparian zones in agricultural catchments, the careful assessment and setting of stream buffer zone widths for timber harvesting operations, and the need for further work to map the extent of natural processes such as bioturbation and stream bank erosion. To mitigate these issues, government policy and legislation will need to focus on the preservation and enhancement of the Crown land riparian zones. Recommended changes to current administrative land management arrangements for these sensitive areas include a move from licensing riparian zones for agricultural practices such as grazing to conservation.
114

The socio-ecology of two species of Australian native rodent - Notomys mitchelli and Notomys alexis.

Bradley, Clare Eileen January 2009 (has links)
Past research suggests that social organisation in Australian rodent species is determined by the predictability of resources in the environment (Happold 1976a). Notomys alexis (the spinifex hopping mouse or tarrkawarra) is widely distributed throughout the Australian arid-zone (Breed 1998a; Watts & Aslin 1981). Large groups of animals have been found sharing burrows in the wild and laboratory observations suggest that the species is highly social (Happold 1976a; Stanley 1971). A closely related species, Notomys mitchelli (Mitchell’s hopping mouse or pankot) is relatively common throughout the southern semi-arid zone (Watts 1998a; Watts & Aslin 1981). Much less is known about N. mitchelli; field studies have been subject to low recapture rates and few laboratory studies have involved this species (Baverstock 1979; Cockburn 1981a; Crichton 1974). Following Happold (1976a), it was hypothesised that the socio-ecology of N. mitchelli will be qualitatively different to that of N. alexis. Studying wild populations of Notomys mitchelli in the Middleback Ranges, South Australia and N. alexis outside the desert township of Roxby Downs, S.A., this research aimed to describe the socio-ecology of these species, with reference to the predictability of their environments. Uniquely, bioclimatic modelling of the species’ known distributions was also conducted to confirm that the study’s underlying assumption that the two rodents inhabit essentially different environments was correct. These studies were complemented by the observation of captive groups of N. alexis. This work confirmed that the habitats of Notomys mitchelli and N. alexis are distinct; the more arid habitat of N. alexis is subject to greater environmental fluctuations than that of the semi-arid dwelling N. mitchelli. Contrary to expectations, however, observation of free-living animals characterised N. mitchelli social groups as highly unstable; while particular individuals remained in the population for long periods, many animals appeared to be transients. Further, burrow groups appeared to be much smaller than predicted by Happold (1976a), and based on loose aggregations of male animals rather than small groups of females. While decidedly social in the laboratory, free-living N. alexis lived in groups no bigger than N. mitchelli and these groups were equally ephemeral in constitution. Moreover, free-living N. alexis appeared to utilise activity areas that were no larger than those used by N. mitchelli, despite occupying a more unpredictable and apparently less well-resourced habitat. As a whole, this research represents a comprehensive examination of the principal behavioural theory commonly applied to Australian native rodent species, untested since its publication three decades ago. From the data collected during this work, it cannot be said that the environmental predictability hypothesis for native rodent social organisations as proposed by Happold (1976a) is adequate to differentiate the social behaviour of these semi-arid and arid-dwelling species. Instead, it is suggested that, while both N. mitchelli and N. alexis are undoubtedly socially tolerant, predation and/or parasite load, driving burrowing behaviour, has a greater influence on the social behaviour of free-living rodent populations than habitat predictability. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1373743 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009
115

Studies of vitamin B₁₂ metabolism in sheep

Gruner, Tini Maria January 2001 (has links)
Vitamin B₁₂ deficiency has been difficult to diagnose, mainly due to the vitamin's lack of biological significance in serum in which it is usually assayed. This research has investigated the marker of vitamin B₁₂/cobalt (Co) deficiency in sheep, methylmalonic acid (MMA), in comparison with serum and liver vitamin B₁₂ concentrations in farm situations where vitamin B₁₂ deficiency is expected in order to establish more accurate reference ranges for serum and liver vitamin B₁₂, and MMA. In addition, an attempt was made to ascertain the vitamin B₁₂ requirements of preruminant (PR) lambs, and to determine whether metabolic demand for vitamin B₁₂ influences tissue concentrations. Furthermore, since the vitamin is active in biological tissues in form of its coenzymes, 5’ -deoxyadenosylcobalamin and methylcobalamin, a preliminary assessment of variation in the distribution of these coenzymes in liver in different situations has been sought. The first trial was set up to find out if the addition of propionate to the PR lamb's diet stimulated the uptake and/or storage of vitamin B₁₂ in the liver as a reflection of the need to deal with the incoming propionate. Sixteen ten day old lambs (Dorset Down/Coopworth cross-bred) were housed indoors soon after birth and fed on milk replacer. For half of the lambs 7.5 % (w:w) of the milk powder was replaced by propionate. Within each group, four lambs were treated with 250 µg vitamin B₁₂ twice weekly. Supplementation with vitamin B₁₂ increased liver concentrations from ~250 to ~900 nmol/kg fresh tissue, but there was no effect of propionate. Propionate addition did, however, result in increased plasma vitamin B₁₂ concentrations in vitamin B₁₂ supplemented groups, values being 3323 and 2355 pmol/l in propionate supplemented and control groups, respectively. This suggested that diet could influence plasma vitamin B₁₂ concentrations. An attempt was made to quantify the PR lamb's ability to absorb vitamin B₁₂ from the alimentary tract by comparing the ability of intra-muscular (IM) and oral vitamin B₁₂ to raise plasma and liver vitamin B₁₂ concentrations. Twenty-seven three to four day old lambs from a farm with marginal Co status were housed indoors and fed on milk replacer. They were divided into three groups: control (n=3), IM treatment (n=12) and oral treatment (n=12). The two treatment groups were further subdivided into five sub-groups. These received, respectively, 0.2 (n=3), 0.4 (n=2), 0.8 (n=2), 1.6 (n=2) and 3.2 µg OH-cbl/d (n=3). The oral groups received tenfold the amount of the comparable IM groups, on the assumption that if oral absorption of the vitamin is about 10 % both groups would show similar increases in plasma and liver vitamin B₁₂ concentration. None of the IM groups showed any significant change in plasma or liver vitamin B₁₂. In the oral groups only the group on the highest dose of vitamin B₁₂, viz 32 µg/d, showed increases in plasma and liver concentrations. It was concluded that either absorption of vitamin B₁₂ was greater than 10 % or that the vitamin was retained better when administered orally. The amount retained in the livers of the lambs in the highest oral group was calculated to represent ~ 7.5 % of the dose. In a follow-up 24 h trial, 14 of the above lambs were divided into three groups: Control (n=3), oral (n=6) and IM (n=5) treatment. The IM group received 3.2 µg OH-cbl and the oral group tenfold the amount as single doses at 0800 h. Blood samples were taken at regular intervals throughout the 24 h period and assayed for vitamin B₁₂, Vitamin B₁₂ concentrations in the IM group rose steeply within the first hour after injection to a concentration that was calculated to reflect 100 % uptake of the vitamin. It rose more slowly over about 8 h in the oral group. From the area under the curve absorption of the oral dose was estimated to be ~ 7 %. The next experiment involved a farm where Co deficiency had been reported previously. In the first year, 50 pregnant two-tooth Half-bred ewes were divided randomly into two groups of 25. One group received a Co bullet plus 1000 µg OH-cb1 IM, the other group remained unsupplemented. In the following year the trial was repeated. Ewes from the previous year's trial (by then four-tooths) were augmented by a new cohort of pregnant two-tooths to make up numbers to 75. After lambing the lambs were divided into four groups: first by their dams' vitamin B₁₂ treatment, then half of each group received injections of vitamin B₁₂ at approximately three weekly intervals while the other half remained untreated. The trials lasted about five months, from mid-pregnancy until weaning. Pasture Co was at its lowest at lambing in both years, 0.09 and 0.10µg/g DM, respectively. In the first year, vitamin B₁₂ concentrations in the untreated ewes rose from 340 to 950 pmol/l in plasma and decreased in liver from 330 to 170 nmol/kg fresh tissue. In the Co treated group, vitamin B₁₂ concentrations in plasma rose from 500 to 1550 pmol/l and in liver from 310 to 560 nmol/kg fresh tissue. In the second year, vitamin B₁₂ concentrations in serum in the unsupplemented groups fell from 500 to 260 pmol/l around lambing before rising again to starting values at weaning, and liver vitamin B₁₂ concentrations fell from 450 at the start to 230 nmol/kg fresh tissue at the end of the trial. Serum vitamin B₁₂ concentrations in the two-tooth supplemented group rose from < 500 to > 3000 pmol/l whereas in the four-tooth supplemented group serum vitamin B₁₂ levels started at ~2800 and rose to nearly 5000 pmol/l. The supplemented four-tooths maintained higher liver vitamin B₁₂ concentrations throughout compared to the supplemented two-tooths, viz 680 compared to below 400 at the start and 900 versus 650 nmol/kg fresh tissue at weaning, respectively. MMA in the untreated groups rose to 15 and to 8 µmol/l during early lactation in the first and second years, respectively, whereas MMA in the treated groups stayed below 3 µmol/l in the first season and below 1.5 µmol/l in the second season. There was a live weight response to treatment in the ewes as the unsupplemented groups showed a significantly lower weight gain during the trials than the supplemented groups, viz 10.0 versus 13.6 kg in the first year, and 10.6 versus 13.3 kg in the four-tooths and 9.9 versus 12.1 kg in the two-tooths in the second year. There was also a significant difference in faecal egg count (FEC) in the first year. FEC in the untreated group was higher during lactation than in the treated group, viz 590 versus 170 eggs per gram wet faeces (epg), respectively. In the second year, the two-tooths had a higher FEC than the four-tooths, viz 120 versus 40 epg during the same time span, respectively. While there was a trend for treatment having an effect on FEC similar to that in the first year it was not significant. Supplementation of ewes in the first year increased mean milk vitamin B₁₂ concentrations at lambing from 800 to 1400 pmol/l and at weaning from 1750 to 4000 pmol/l. In the second year, Co bullet treatment increased milk vitamin B₁₂ concentrations in the four-tooths and two-tooths from 1500 and 2300 to 4000 and 2900 pmol/l at lambing, and from 1800 and 1400 to 6200 and 4500 pmol/l at weaning, respectively. Treatment of ewes increased vitamin B₁₂ concentrations in the lambs which were not themselves supplemented. Plasma values in the first year increased from 160 to 325 pmol/l soon after birth and from 650 to 900 pmol/l at weaning, and liver values from 75 to 140 nmol/kg fresh tissue soon after birth and from 150 to 240 nmol/kg fresh tissue at weaning. In the second year, plasma vitamin B₁₂ concentrations increased from 160 to 380 pmol/l soon after birth and from 500 to 700 pmol/l at weaning, and in liver from 130 to 260 nmol/kg fresh tissue soon after birth and from 220 to 340 nmol/kg fresh tissue at weaning. There was also a significant effect of ewe supplementation on lamb MMA in 1997/1998 when values decreased from 19 to 8 µmol/l around the time of rumen development. MMA in the second year stayed below 3 µmol/l throughout in all groups of lambs. There was no difference in LWG between any groups of lambs. FEC was lowest in the group where both ewes and lambs were supplemented and highest in the group where neither ewes nor lambs were treated. Further investigations were conducted on farms in Southland with lambs post-weaning in order to compare changes in serum and liver vitamin B₁₂ with serum MMA and LWG to determine the critical time and level of deficiency. In the first year, three farms with 50 lambs each participated. Lambs from each farm were allocated to five groups of 10 animals each. The first group received a Co bullet at weaning, and each month another group was treated with a Co bullet. The lambs were weighed monthly, and blood and liver samples were taken prior to treatment and each subsequent month from five lambs of the first supplemented group. The trial lasted about four months. Serum vitamin B₁₂ concentrations in lambs at weaning were between 500 and 1000 pmol/l. Although supplementation increased serum levels for the first month this was followed by a drop to near or below starting concentrations. An exception was Farm 3 where serum vitamin B₁₂ concentrations rose again at the end of the trial. Liver vitamin B₁₂ concentrations also showed an overall decline from starting levels (200 to 300 nmol/kg fresh tissue) to the end of the trial (100 to 200 nmol/kg fresh tissue). MMA started around 2 µmol/l and reached between 6 and 7 µmol/l in the untreated lambs on Farms 1 and 3 two months after weaning before decreasing to around 3 µmol/l at the end of the trial, whereas the treated lambs maintained MMA concentrations around 2 µmol/l. On Farm 2 MMA started just below 5 µmol/l, decreased to around 1 µmol/l for treated and untreated lambs one month later and rose again to between 2.5 and 4 µmol/l, respectively, at the end of the trial. LWG was below average for all lambs (between 0.20 and 0.04 kg/d except for Farm I in the first month after weaning) but no significant differences were noted between treated and untreated lambs on any of the farms. Another trial was conducted on one of these farms in the following year. One hundred lambs were divided into two groups of 50 each at weaning and sampled monthly for about six months. One group was treated with two Co bullets, the other group remained untreated. Pasture Co was between 0.04 and 0.07 µg/g DM, yet serum levels for the untreated group stayed ~500 pmol/l throughout the trial. Serum vitamin B₁₂ concentrations for the treated group started at ~500 pmol/l, rose to ~2500 pmol/l before falling back to ~2000 pmol/l. Liver vitamin B₁₂ concentrations for the untreated and treated groups were 529 and 427 nmol/kg fresh tissue at weaning, respectively. This decreased for both groups to ~350 nmol/kg fresh tissue one month after weaning. In the untreated lambs liver values decreased further to ~290 nmol/kg fresh tissue whereas they increased to ~450 nmol/kg fresh tissue for the treated group at the end of the trial. MMA concentrations started between 2 and 3 µmol/l for both groups and increased to 4.5 µmol/l for the untreated group one month later before falling back to 3.2 µmol/l. In the treated group MMA decreased to ~1µmol/l and stayed at that level throughout the trial. There was no difference in weight gain. In order to obtain an understanding of the distribution of corrinoids in biological tissues a High Performance Liquid Chromatography method was developed. The sensitivity of the analytical method meant that it was only practical to assay mainly liver samples because of the higher vitamin B₁₂ concentrations than in other tissues. The general finding was that the coenzyme 5’ –deoxyadenosylcobalamin (ado-cbl) constituted the highest proportion of corrinoids in liver (45 %), followed by analogues (28 %), OH-cbl (24 %) and lastly methy1cobalamin (3 %). Ado-cbl did tend to be proportionately higher in supplemented than in unsupplemented animals (56 and 42 %, respectively), whereas biologically non-active analogues tended to be higher in untreated than in treated sheep (29 and 21 %, respectively). It was concluded that in the farm trials Co deficiency was only mild or not present although deficiency would have been predicted from the low vitamin B₁₂ concentrations in serum and liver and from raised MMA values. Therefore, currently used thresholds in New Zealand appear to be too high for vitamin B₁₂, and overseas values for MMA do not seem to be appropriate. Revised marginal ranges of 100 to 200 pmol/l for serum, 100 to 200 nmol/kg fresh tissue for liver and 10 to 20 µmol/l for MMA are suggested. Further, this work shows that Co bullets were effective in elevating blood and liver vitamin B₁₂concentrations for longer than one year. In the trials with preruminant lambs it was found that maintenance requirements were met by the vitamin B₁₂ content of milk replacer. There is evidence from indoor and farm trials that vitamin B₁₂ from milk was much more readily absorbed than vitamin B₁₂ from supplements. It was estimated that suckling lambs probably require between 1200 and 4000 pmol vitamin B₁₂/d, depending on age.
116

The socio-ecology of two species of Australian native rodent - Notomys mitchelli and Notomys alexis.

Bradley, Clare Eileen January 2009 (has links)
Past research suggests that social organisation in Australian rodent species is determined by the predictability of resources in the environment (Happold 1976a). Notomys alexis (the spinifex hopping mouse or tarrkawarra) is widely distributed throughout the Australian arid-zone (Breed 1998a; Watts & Aslin 1981). Large groups of animals have been found sharing burrows in the wild and laboratory observations suggest that the species is highly social (Happold 1976a; Stanley 1971). A closely related species, Notomys mitchelli (Mitchell’s hopping mouse or pankot) is relatively common throughout the southern semi-arid zone (Watts 1998a; Watts & Aslin 1981). Much less is known about N. mitchelli; field studies have been subject to low recapture rates and few laboratory studies have involved this species (Baverstock 1979; Cockburn 1981a; Crichton 1974). Following Happold (1976a), it was hypothesised that the socio-ecology of N. mitchelli will be qualitatively different to that of N. alexis. Studying wild populations of Notomys mitchelli in the Middleback Ranges, South Australia and N. alexis outside the desert township of Roxby Downs, S.A., this research aimed to describe the socio-ecology of these species, with reference to the predictability of their environments. Uniquely, bioclimatic modelling of the species’ known distributions was also conducted to confirm that the study’s underlying assumption that the two rodents inhabit essentially different environments was correct. These studies were complemented by the observation of captive groups of N. alexis. This work confirmed that the habitats of Notomys mitchelli and N. alexis are distinct; the more arid habitat of N. alexis is subject to greater environmental fluctuations than that of the semi-arid dwelling N. mitchelli. Contrary to expectations, however, observation of free-living animals characterised N. mitchelli social groups as highly unstable; while particular individuals remained in the population for long periods, many animals appeared to be transients. Further, burrow groups appeared to be much smaller than predicted by Happold (1976a), and based on loose aggregations of male animals rather than small groups of females. While decidedly social in the laboratory, free-living N. alexis lived in groups no bigger than N. mitchelli and these groups were equally ephemeral in constitution. Moreover, free-living N. alexis appeared to utilise activity areas that were no larger than those used by N. mitchelli, despite occupying a more unpredictable and apparently less well-resourced habitat. As a whole, this research represents a comprehensive examination of the principal behavioural theory commonly applied to Australian native rodent species, untested since its publication three decades ago. From the data collected during this work, it cannot be said that the environmental predictability hypothesis for native rodent social organisations as proposed by Happold (1976a) is adequate to differentiate the social behaviour of these semi-arid and arid-dwelling species. Instead, it is suggested that, while both N. mitchelli and N. alexis are undoubtedly socially tolerant, predation and/or parasite load, driving burrowing behaviour, has a greater influence on the social behaviour of free-living rodent populations than habitat predictability. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1373743 / Thesis (Ph.D.) - University of Adelaide, School of Earth and Environmental Sciences, 2009
117

Estudo e otimização dos parâmetros de processamento por radiação gama em escala industrial considerando fatores operacionais / Study and optimization of parameters of gamma ray processing in industrial scale considering operational factors

SANTOS, PAULO de S. 23 November 2017 (has links)
Submitted by Pedro Silva Filho (pfsilva@ipen.br) on 2017-11-23T11:10:00Z No. of bitstreams: 0 / Made available in DSpace on 2017-11-23T11:10:00Z (GMT). No. of bitstreams: 0 / O processamento por radiação gama para beneficiamento de produtos tem se tornado uma tecnologia aceita mundialmente. Tem como aplicações a esterilização de produtos médicos, a irradiação de alimentos e produtos agrícolas, a modificação de materiais poliméricos e biomateriais, a preservação de objetos de patrimônio cultural, a esterilização de tecidos humanos para transplante, a mudança de cor em gemas, dentre outros. Desde 2004, o Irradiador Multipropósito de Cobalto-60 do Centro de Tecnologia das Radiações do IPEN tem sido utilizado no estudo e aperfeiçoamento dessas aplicações com objetivos de pesquisa e no estabelecimento de aplicações rotineiras. Este, embora concebido para trabalhar no modo contínuo de irradiação, é utilizado no modo estacionário mais indicado para irradiações de materiais delicados ou de pesquisa. Neste trabalho foram validadas e verificadas experimentalmente as adequações dos métodos à irradiação estacionária; bem como as interrupções para medição de doses em dosímetros de polimetilmetacrilato em processos fracionados, onde seu uso se mostrou adequado para taxas de dose maiores que 2kGy·h-1. A descrição do processo de carga das fontes mostra a importância do seu planejamento e seu impacto na distribuição de taxas de dose. Os mapeamentos das doses e taxas de dose permitiram localizar regiões de valores homogêneos e máximos. Foi estabelecido um procedimento de irradiação de tecidos para aloenxertia utilizando monitoração dosimétrica externa. Foram levantados os custos e despesas de irradiação, aplicáveis a instalações governamentais. O balanço energético da piscina de armazenamento das fontes permitiu calcular o fluxo de calor do sistema e definir as condições máximas de operação sem trocador de calor. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP
118

Ridge Cultivation for the Adaption of Fodder Maize (Zea mays L.) to Suboptimal Conditions of Low Mountain Ranges in Organic Farming in Central Europe

Krachunova, Tsvetelina, Scholz, Martin, Bellingrath-Kimura, Sonoko Dorothea, Schmidtke, Knut 04 May 2023 (has links)
Fodder maize cultivation under low mountain conditions in Central Europe presents obstacles for organic dairy farmers; low temperatures and high precipitation values in spring delay the juvenile development of maize, which leads to lower and fluctuating yields. Increasing the soil temperature during the critical growth phase of maize in spring is beneficial for maize cultivation. For this reason, 0.15 m high ridge-row cultivation (RCM) of maize was compared to a typical flat surface cultivation method (FCM) with 0.75 m row spacing in three environments (En) in 2017, 2018 and 2020 on-farm at low mountain sites in Germany. In the experiment, with randomised block design and one-factorial arrangement, soil temperature (ST) at 0.05 m soil depth at midday, field emergence (FE) 4, 8, 16 and 20 days after sowing (DAS), dry matter yields (DM) in every En and plant development and N, P, K content in En 2020 were investigated. RCM led to a significantly higher ST 4 DAS in every En, 12 and 20 days in 2018 and 8 and 16 DAS in 2020. RCM did not accelerate maize FE but positively impacted plant development and starch content. RCM generated a higher dry matter (DM) yield of whole maize plants and corn cobs, and a higher protein yield than FCM. RCM slightly increased the plant-available P and Mg content from 0 to 0.3 m and influenced significantly the mineral N content from 0 to 0.3 m at the beginning of grain development. RCM, a simple cultivation technique, demonstrated benefits for maize cultivation, particularly for climatically marginal locations in Germany.
119

Migration ecology of American White Pelicans: circannual movement, geographic range, and annual survival

Ogawa, Ryo 13 May 2022 (has links) (PDF)
Responses of migratory birds to seasonal climate and long-term environmental changes have been a central theme of avian migration ecology. Atmospheric conditions (e.g., winds and thermals), climate, and land cover and land use (LCLU) are major factors influencing the flights of soaring birds. Soaring American White Pelicans (Pelecanus erythrorhynchos) (hereafter, AWPEs) migrate between the subtropical Gulf of Mexico (GOM) and the temperate Northern Great Plains. American White Pelicans are also economically important piscivorous birds, causing enormous damages to the commercial Channel Catfish (Ictalurus punctatus) aquaculture in the Southeastern US. My studies aimed to evaluate the effects of climate, wind, and LCLU on the geographic range distributions, seasonal movements, and annual survival of AWPEs. I used Bayesian integrated species distribution models to estimate the occupancy probability and space-use intensity of AWPEs at the breeding and non-breeding grounds in 2005, 2010, and 2015, respectively, with data from eBird, Breeding Bird Survey, and Christmas Bird Count. Decreases in wind speeds and surface net thermal radiation and increases in waterbodies, wetlands, and non-woody covers enhanced AWPE occupancy at both the breeding and non-breeding grounds. I used 72 GPS-tracked AWPE data to study circannual hourly movement speeds and seasonal home ranges of AWPEs from 2002 to 2012. American White Pelicans had shorter hourly movement distances and smaller seasonal home ranges in the Southern than Northern GOM during winters; however, the difference did not carry over to the shared breeding grounds during summers. Last, I built Bayesian integrated population models to estimate annual survival and population dynamics of AWPEs with mark-resight-recovery data and annual nest counts at Chase Lake, North Dakota, the US from 1960 to 2014. Increases in upward wind velocity during autumn migration enhanced hatch-year AWPE survival. Increased winter precipitation on the non-breeding grounds improved annual survival of yearling and adults. On the other hand, increased precipitation at the breeding grounds reduced annual survival of hatch-year AWPEs. My findings can help develop management plans for mitigating the economic damages of AWPEs by predicting what areas AWPEs may occupy with high abundances in the future changes in climate and LCLU.
120

Planning concepts to sustain, develop, and test complex naval combat systems at the Surface Combat Systems Center, Wallops Island, Virginia

Abell, Barry J. 03 1900 (has links)
Approved for public release, distribution is unlimited / The Surface Combat Systems Center (SCSC), Wallops Island, Virginia is a combination of personnel, geography, airspace, and technology located on a barrier island off Virginia's Eastern Shore. First opened in 1985 as a US Navy, AEGIS Land-Based Test Site (LBTS), SCSC has grown to include the Ship Self Defense (SSD), and DD(X) combat system facilities to the site. SCSC is chartered to support computer program development, life cycle and in-service engineering, team training, and research, development, test, and evaluation services while adapting to evolution of US Naval combatants and emerging requirements. The purpose of this document is to present an analysis of existing US Navy shipboard and land-based organization business practices and apply them to the existing SCSC command organization. The objective is to combine US Navy transformation concepts and SCSC planning concepts to provide the documentation needed to support the development of new strategic business plans for the command. The goal is to provide a long-term strategy to transform SCSC into the US Navy's East Coast Weapons Range Facility or otherwise named, the Wallops Island Test and Evaluation Range Facility (WITERF), while maintaining its synergy as a LBTS for research, development, testing and evaluation of naval combat systems. / Civilian, United States Navy

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