The genus Populus is ideally suited to investigate questions related to the interplay between an individual’s environmental history and its capacity to respond to external stimuli. In order to dissect the influence of individual history on subsequent plant responses, transcriptome level changes due to water deficit were assessed in clonal populations of Populus hybrids. Results indicate variation in the drought transcriptomes of genetically identical clones originating from different locations can be shaped by the individual history of the clone. Additionally, yearly variations in drought transcriptome patterns showed specific trends associated with a clonal population that were not related to an unknown influence at a location, nor with the biological source of cuttings. Despite these sources of transcriptome variation, a common shared response was identified across all populations. The findings hint at the influence of the environment and epigenetic factors in the dynamic regulation of transcriptome level responses in clonal individuals.

Univ., Diss.--Göttingen, 2004. / Literaturverz. S. [393] - 410.

Philosophiae Doctor - PhD / Electroanalytical and optical properties of nanoscale materials are very important for biosensing applications as well as for understanding the unique one-dimensional carrier transport mechanism. One-dimensional semiconductor nanomaterials such as semiconductor quantum dots are extremely attractive for designing high-density protein arrays. Because of their high surfaceto-volume ratio, electro-catalytic activity as well as good biocompatibility and novel electron transport properties make them highly attractive materials for ultra-sensitive detection of biological macromolecules via bio-electronic or bio-optic devices. A genosensor or gene based biosensor is an analytical device that employs immobilized deoxyribonucleic acid (DNA) probes as the recognition element and measures specific binding processes such as the formation of deoxyribonucleic acid-deoxyribonucleic acid (DNA-DNA), deoxyribonucleic acid- ribonucleic acid (DNA-RNA) hybrids, or the interactions between proteins or ligand molecules with DNA at the sensor surface.In this thesis, I present four binary and two ternary-electrochemically and optically modulated selenide and telluride quantum dots, all synthesised at room temperature in aqueous media. Cationic gallium (Ga3+) synthesized in form of hydrated gallium perchlorate salt[Ga(ClO4)3.6H2O] from the reaction of hot perchloric acid and gallium metal was used to tailor the optical and electrochemical properties of the selenide and telluride quantum dots. The synthesized cationic gallium also allowed successful synthesis of novel water soluble and biocompatible capped gallium selenide nanocrystals and gallium telluride quantum dots. Cyclic voltammetric studies inferred that presence of gallium in a ZnSe-3MPA quantum dot lattice improved its conductivity and significantly increased the electron transfer rate in ZnTe-3MPA.Utraviolet-visible (UV-vis) studies showed that incorporation of gallium into a ZnSe-3MPA lattice resulted in a blue shift in the absorption edge of ZnSe-3MPA from 350 nm to 325 nm accompanied by decrease in particle size. An amphiphilic bifunctional molecule, 3-Mercaptopropionic acid (3-MPA) was used as a capping agent for all quantum dots. It was found that 3-MPA fully solubilised the quantum dots, made them stable, biocompatible, non agglomerated and improved their electron transfer kinetics when immobilized on gold electrodes.Retention of the capping agent on the quantum dot surface was confirmed by Fourier transform infrared spectroscopy (FTIR) which gave scissor type bending vibrations of C-H groups in the region 1365 cm-1 to 1475 cm-1, stretching vibrations of C=O at 1640 cm-1, symmetric and asymmetric vibrations of the C-H in the region 2850 cm-1 to 3000 cm-1 as well as stretching vibrations of –O-H group at 3435 cm-1. The particle size and level of non-agglomeration of the quantum dots was studied by high resolution transmission electron microscopy (HRTEM). The optical properties of the quantum dots were studied using UV-vis and fluorescence spectroscopic techniques.Quantum dot/nanocrystal modified gold electrodes were prepared by immersing thoroughly cleaned electrodes in the quantum dot/nanocrystal solution, in dark conditions for specific periods of time. The electrochemical properties of the modified electrodes were characterized by cyclic voltammetry (CV), square wave voltammetry (SWV), electrochemical impedance and spectroscopy (EIS). Six sensing platforms were then prepared using quantum dot/nanocrystal, one of which was used for detection of dopamine while the rest were used for detection of a DNA sequence related to 5-enolpyruvylshikimate-3-phosphate synthase, a common vector gene in glyphosate resistant transgenic plants.The first sensing platform, consisting of ZnSe-3MPA modified gold electrode (Au|ZnSe-3MPA) gave rise to a novel method of detecting dopamine in presence of excess uric acid and ascorbic acid. Using a potential window of 0 to 400 mV, the ZnSe-3MPA masked the potential for oxidation of uric and ascorbic acids, allowing detection of dopamine with a detection limit of 2.43 x 10-10 M (for SWV) and 5.65 x 10-10 M (for steady state amperometry), all in presence of excess uric acid (>6500 higher) and ascorbic acid (>16,000 times higher). The detection limit obtained in this sensor was much lower than the concentration of dopamine in human blood(1.31 x 10-9 M), a property that makes this sensor a potential device for detection of levels of dopamine in human blood.The other sensing platforms were prepared by bioconjugation of amine-terminated 20 base oligonucleotide probe DNA (NH2-5′-CCC ACC GGT CCT TCA TGT TC-3′) onto quantum dot modified electrodes with the aid of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS). The prepared DNA electrodes were electrostatically hybridized with different sequences which included 5′-GAA CAT GAA GGA CCG GTG GG-3′ (complementary target), 5′-CATAGTTGCAGCTGCCACTG-3′ (non complementary target) and 5′-GATCATGAAGCACCGGAGGG-3′ (3-base mismatched target).The hybridization events were monitored using differential pulse voltammetry (DPV) and SWV by monitoring the guanine oxidation signal or using EIS by monitoring changes in the charge transfer resistance. The quantum dot genosensors were characterized by low detection limits (in the nanomolar range), long linear range (40 - 150 nM) and were able to discriminate among complementary, non-complementary and 3-base mismatched target sequences.

Esta dissertação é resultado da pesquisa etnográfica desenvolvida junto a os atores envolvidos na gestão ambiental da Unidade de Conservação da Natureza (UC) chamada Floresta Nacional de Passo Fundo (Mato Castelhano/RS). Este universo compõe-se de cientistas, servidores públicos, agricultores e índios kaingang, em diálogo sobre o uso e a preservação da floresta. Nos encontros do Conselho Gestor da UC são expressas visões de mundo que se refletem em formas diferenciadas de apropriação dos elementos do ambiente próprias de cada grupo. Em um contexto de introdução de lavouras transgênicas nas propriedades próximas à área protegida, o estudo visa a apreender pontos de vista sobre a "natureza" e a "sociedade" e sobre o ambiente de Mato Castelhano entre os participantes do Conselho Gestor da UC, pesquisadores, especialistas da área ambiental e agricultores, abordando ainda a perspectiva de índios kaingang acampados na BR-285. Foram realizadas entrevistas semi-estruturadas com índios e conselheiros e observação participante de suas atividades e reuniões, além da análise de documentos. Evidencia-se que o diálogo em relação aos elementos objetos de manejo e conservação é dificultado pela desconsideração da complexidade da maneira de conceber o ambiente entre os diferentes atores locais. / This dissertation results from an ethnographic field work among actors who are involved in a process of public management of an Environmental Protected Area, which is called National Forest of Passo Fundo (Mato Castelhano/RS). This universe is composed of scientists, public servants, farmers and a kaingang indigenous group, dialoging about the use of "nature" and its conservancy. In the gatherings of the Management Council of the National Forest are expressed different perspectives in what concerns the appropriation of the area and its elements, which are related to each one's ways to engage themselves in that environment. In a context of transgenic agriculture in the farms around the protected area, the study focus the apprehension of points of view related to "nature" and "society", as well as the environment of Mato Castelhano, among members of the Council, professional researchers, experts on environment issues, farmers, and includes the perspective of the kaingang indians. In a qualitative approach, were made analysis of documents, semi-directive interviews and participant observation during ordinary meetings and tasks of the councilors, and within the indigenous encampment on the highway BR-285. The research evidences that the dialog about use and conservancy of "natural" elements do not reach to consider the different ways of conceive environment among the local actors.

Esta dissertação é resultado da pesquisa etnográfica desenvolvida junto a os atores envolvidos na gestão ambiental da Unidade de Conservação da Natureza (UC) chamada Floresta Nacional de Passo Fundo (Mato Castelhano/RS). Este universo compõe-se de cientistas, servidores públicos, agricultores e índios kaingang, em diálogo sobre o uso e a preservação da floresta. Nos encontros do Conselho Gestor da UC são expressas visões de mundo que se refletem em formas diferenciadas de apropriação dos elementos do ambiente próprias de cada grupo. Em um contexto de introdução de lavouras transgênicas nas propriedades próximas à área protegida, o estudo visa a apreender pontos de vista sobre a "natureza" e a "sociedade" e sobre o ambiente de Mato Castelhano entre os participantes do Conselho Gestor da UC, pesquisadores, especialistas da área ambiental e agricultores, abordando ainda a perspectiva de índios kaingang acampados na BR-285. Foram realizadas entrevistas semi-estruturadas com índios e conselheiros e observação participante de suas atividades e reuniões, além da análise de documentos. Evidencia-se que o diálogo em relação aos elementos objetos de manejo e conservação é dificultado pela desconsideração da complexidade da maneira de conceber o ambiente entre os diferentes atores locais. / This dissertation results from an ethnographic field work among actors who are involved in a process of public management of an Environmental Protected Area, which is called National Forest of Passo Fundo (Mato Castelhano/RS). This universe is composed of scientists, public servants, farmers and a kaingang indigenous group, dialoging about the use of "nature" and its conservancy. In the gatherings of the Management Council of the National Forest are expressed different perspectives in what concerns the appropriation of the area and its elements, which are related to each one's ways to engage themselves in that environment. In a context of transgenic agriculture in the farms around the protected area, the study focus the apprehension of points of view related to "nature" and "society", as well as the environment of Mato Castelhano, among members of the Council, professional researchers, experts on environment issues, farmers, and includes the perspective of the kaingang indians. In a qualitative approach, were made analysis of documents, semi-directive interviews and participant observation during ordinary meetings and tasks of the councilors, and within the indigenous encampment on the highway BR-285. The research evidences that the dialog about use and conservancy of "natural" elements do not reach to consider the different ways of conceive environment among the local actors.

Esta dissertação é resultado da pesquisa etnográfica desenvolvida junto a os atores envolvidos na gestão ambiental da Unidade de Conservação da Natureza (UC) chamada Floresta Nacional de Passo Fundo (Mato Castelhano/RS). Este universo compõe-se de cientistas, servidores públicos, agricultores e índios kaingang, em diálogo sobre o uso e a preservação da floresta. Nos encontros do Conselho Gestor da UC são expressas visões de mundo que se refletem em formas diferenciadas de apropriação dos elementos do ambiente próprias de cada grupo. Em um contexto de introdução de lavouras transgênicas nas propriedades próximas à área protegida, o estudo visa a apreender pontos de vista sobre a "natureza" e a "sociedade" e sobre o ambiente de Mato Castelhano entre os participantes do Conselho Gestor da UC, pesquisadores, especialistas da área ambiental e agricultores, abordando ainda a perspectiva de índios kaingang acampados na BR-285. Foram realizadas entrevistas semi-estruturadas com índios e conselheiros e observação participante de suas atividades e reuniões, além da análise de documentos. Evidencia-se que o diálogo em relação aos elementos objetos de manejo e conservação é dificultado pela desconsideração da complexidade da maneira de conceber o ambiente entre os diferentes atores locais. / This dissertation results from an ethnographic field work among actors who are involved in a process of public management of an Environmental Protected Area, which is called National Forest of Passo Fundo (Mato Castelhano/RS). This universe is composed of scientists, public servants, farmers and a kaingang indigenous group, dialoging about the use of "nature" and its conservancy. In the gatherings of the Management Council of the National Forest are expressed different perspectives in what concerns the appropriation of the area and its elements, which are related to each one's ways to engage themselves in that environment. In a context of transgenic agriculture in the farms around the protected area, the study focus the apprehension of points of view related to "nature" and "society", as well as the environment of Mato Castelhano, among members of the Council, professional researchers, experts on environment issues, farmers, and includes the perspective of the kaingang indians. In a qualitative approach, were made analysis of documents, semi-directive interviews and participant observation during ordinary meetings and tasks of the councilors, and within the indigenous encampment on the highway BR-285. The research evidences that the dialog about use and conservancy of "natural" elements do not reach to consider the different ways of conceive environment among the local actors.

Genetically modified (GM) crops are commercially cultivated worldwide but there are concerns on their possible negative impacts on soil biodiversity. A glasshouse study was conducted to determine effects of Bt maize residues on soil microbial diversity. Residues of Bt maize (PAN 6Q-308B) and non-Bt maize (PAN 6Q-121) were incorporated into the soil and corresponding maize seeds planted. The treatments were replicated three times. Fertilizer and water application were similar for both treatments. Rhizosphere and bulk soil was destructively sampled from each treatment and analyzed for microbial community level physiological profiles using Biolog plates with 31 different carbon substrates. Absorbance in the Biolog plates was recorded after 72 h of incubation at 20oC. Arbuscular mycorrhizal fungi spore counts were also determined. Field studies were conducted at the University of Free State and University of Fort Hare Research Farms to determine the effects of growing Bt maize on soil microbial diversity. One Bt maize cultivar (PAN6Q-308B) and non-Bt maize (PAN6Q-121) were grown in a paired experiment at University of Free State farm, while two Bt maize (DKC61-25B and PAN6Q-321B) and their near-isogenic non-Bt maize lines (DKC61-24 and PAN6777) were grown in a randomized complete block design with three replicates. Fertilization, weed control and water application, were similar for both Bt maize cultivars and their non-Bt maize counterparts. Rhizosphere soil samples were collected by uprooting whole plants and collecting the soil attached to the roots. The samples were analysed for microbial diversity and for arbuscular mycorrhizae fungal spore counts. Principal component analysis showed that soil microbial diversity was affected more by sampling time whereas genetic modification had minimal effects. Presence of residues also increased the diversity of microorganisms. Mycorrhizal fungal spores were not affected by the presence of Bt maize residues. Growing Bt maize had no effect on the soil microbial diversity in the rhizosphere.

In teleosts, elevated temperature during embryogenesis can act on germline cell development, which in turn plays a role for sexual fate. In Nile tilapia, a species with high-temperature-induced masculinization, little is known about the effects of increased temperature on gonadal development in non-masculinized females. The aim of the present work was to investigate persistent effects on the germline of genetically female (XX) Nile tilapia reared at normal (28 ° C) or elevated temperature (36°C) during the critical time of gonadal sex differentiation at 10 to 20 days post fertilization. Nonsex-reversed females were compared to control females to determine persistent effects of temperature on subsequent ovarian development using histological approaches. Germline stem cells were identified using the germline marker Vasa in combination with the proliferation marker PCNA. Vasa- and PCNA-positive germline stem cells were found in ovaries of both high-temperature-treated and control females. In both groups, ovarian germline stem cells were located at the germinal epithelium of the ovigerous lamellae. Although no detrimental effects of high temperature on gonadal development in female Nile tilapia were observed, implications on the reproductive fitness caused by elevated temperature need to be investigated in greater depth.

<div><div>In the forensic science community, there is a vast need for tools to help assist investigations when standard DNA profiling methods are uninformative. Methods such as Forensic DNA Phenotyping (FDP) and proteomics aims to help this problem and provide aid in investigations when other methods have been exhausted. FDP is useful by providing physical appearance information, while proteomics allows for the examination of difficult samples, such as hair, to infer human identity and ancestry. To create a “biological eye witness” or develop informative probability of identity match statistics through proteomically inferred genetic profiles, it is necessary to constantly strive to improve these methods. </div><div><br></div><div>Currently, two developmentally validated FDP prediction assays, ‘HIrisPlex’ and ‘HIrisplex-S’, are used on the capillary electrophoresis to develop a phenotypic prediction for eye, hair, and skin color based on 41 variants. Although highly useful, these assays are limited in their ability when used on the CE due to a 25 variant per assay cap. To overcome these limitations and expand the capacities of FDP, we successfully designed and validated a massive parallel sequencing (MPS) assay for use on both the ThermoFisher Scientific Ion Torrent and Illumina MiSeq systems that incorporates all HIrisPlex-S variants into one sensitive assay. With the migration of this assay to an MPS platform, we were able to create a semi-automated pipeline to extract SNP-specific sequencing data that can then be easily uploaded to the freely accessible online phenotypic prediction tool (found at https://hirisplex.erasmusmc.nl) and a mixture deconvolution tool with built-in read count thresholds. Based on sequencing reads counts, this tool can be used to assist in the separation of difficult two-person mixture samples and outline the confidence in each genotype call.<br></div><div><br></div><div>In addition to FDP, proteomic methods, specifically in hair protein analysis, opens doors and possibilities for forensic investigations when standard DNA profiling methods come up short. Here, we analyzed 233 genetically variant peptides (GVPs) within hair-associated proteins and genes for 66 individuals. We assessed the proteomic methods ability to accurately infer and detect genotypes at each of the 233 SNPs and generated statistics for the probability of identity (PID). Of these markers, 32 passed all quality control and population genetics criteria and displayed an average PID of 3.58 x 10-4. A population genetics assessment was also conducted to identify any SNP that could be used to infer ancestry and/or identity. Providing this information is valuable for the future use of this set of markers for human identification in forensic science settings. </div></div><div><br></div>

The theoretical part of the diploma thesis summarizes basic facts related to the global climate change and provides up-to-date knowledge on the issue of genetically modified plants more resistant to stress factors of environment, including specific examples of strategies regarding preparation of genetically modified plants resistant particularly to abiotic stress. Although genetically modified plants and global climate changes belong to very important and current issue which public and foremost young generation should be sufficiently aware of, contemporary biology books and high school framework educational program pay to the issue very little attention. Therefore, the goal of this thesis is not only to summarize the basic facts and current knowledge regarding this issue but mainly to handle the issue in didactic level in the form of activating learning tasks. There were 28 learning tasks created in the thesis that gradually in unconventional way familiarize students with the issue of genetically modified plants and with the impacts of climate changes. Students must actively acquire information from accompanying materials to address the tasks properly, think critically over them, utilizing acquired knowledge and experience from the past to some extent. Fourteen tasks were chosen from the file created which...