A holistic approach to reduce negative impacts of hydropeaking

Hydropeaking is a common phenomenon of water courses that are affected by peak energy production of hydro power plants. It may cause severe impacts on the biodiversity of a stream. In fact, due to hydropeaking fishes, macroinvertebrates and aquatic plants undergo a major stress and frequently they are not able to survive these frequent water level fluctuations. In this paper a case study is presented where several mitigation measures for an affected river are evaluated. Abiotic indicators representing the hydropeaking phenomenon and responsible for an impaired biodiversity are calculated and compared. Furthermore a cost-benefit analysis of the mitigation measures is carried out allowing to define the measures to be realized. Facing the challenge of a holistic approach the study is embedded in a project with public participation of all concerned stakeholders addressing also the need of flood protection and ecologically sound river restoration

Proteomic profiling identifies breast tumor metastasis-associated factors in an isogenic model

A combination of LC and MS was applied to an isogenic breast tumor metastasis model to identify proteins associated with a cellular phenotype. Chromatofocusing followed by nonporous-RP-HPLC/ESI-TOF MS was applied to cell lysates of a pair of monoclonal cell lines from the human breast carcinoma cell line MDA-MB-435 that have different metastatic phenotypes in immune-compromised mice. This method was developed to separate proteins based on p I and hydrophobicity. The high resolution and mass accuracy of ESI-TOF measurements provided a good correlation of theoretical MW and experimental M r values of intact proteins measured in mass maps obtained in the pH range 3.8–6.4. The isolated proteins were digested by trypsin and analyzed by MALDI-TOF MS, MALDI-QIT-TOF MS, and monolith-based HPLC/MS/MS. The unique combination of the techniques provided valuable information including quantitation and modification of proteins. We identified 89 selected proteins, of which 43 were confirmed as differentially expressed. Metastasis-associated proteins included galectin-1, whereas annexin I and annexin II were associated with the nonmetastatic phenotype. In this study, we demonstrate that combining a variety of MS tools with a multidimensional liquid-phase separation provides the ability to map cellular protein content, to search for modified proteins, and to correlate protein expression with cellular phenotype.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/55918/1/299_ftp.pd

Potential of poly(styrene-co-divinylbenzene) monolithic columns for the LC-MS analysis of protein digests

Two polystyrene-based capillary monolithic columns of different length (50 and 250 mm) were used to evaluate the effects of column length on gradient separation of protein digests. A tryptic digest of a 9-protein mixture was used as a test sample. Peak capacities were determined from selected extracted ion chromatograms, and tandem mass spectrometry data were used for database matching using the MASCOT search engine. Peak capacities and protein identification scores were higher for the long column with all gradients. Peak capacities appear to approach a plateau for longer gradient times; maximum peak capacity was estimated to be 294 for the short column and 370 for the long column. Analyses with similar gradient slope produced a ratio of the peak capacities of 3.36 for the long and the short column, which is slightly higher than the expected value of the square root of the column length ratio. The use of a longer monolith improves peptide separation, as reflected by higher peak capacity, and also increases protein identification, as observed from higher identification scores and a larger number of identified peptides. Attention has also been paid to the peak production rate (PPR, peak capacity per unit time). For short analysis times, the short column produces a higher PPR, while for analysis times longer than 40 min, the PPR of the 250-mm column is higher

An analytical platform for mass spectrometry-based identification and chemical analysis of RNA in ribonucleoprotein complexes

We describe here a mass spectrometry (MS)-based analytical platform of RNA, which combines direct nano-flow reversed-phase liquid chromatography (RPLC) on a spray tip column and a high-resolution LTQ-Orbitrap mass spectrometer. Operating RPLC under a very low flow rate with volatile solvents and MS in the negative mode, we could estimate highly accurate mass values sufficient to predict the nucleotide composition of a ∼21-nucleotide small interfering RNA, detect post-transcriptional modifications in yeast tRNA, and perform collision-induced dissociation/tandem MS-based structural analysis of nucleolytic fragments of RNA at a sub-femtomole level. Importantly, the method allowed the identification and chemical analysis of small RNAs in ribonucleoprotein (RNP) complex, such as the pre-spliceosomal RNP complex, which was pulled down from cultured cells with a tagged protein cofactor as bait. We have recently developed a unique genome-oriented database search engine, Ariadne, which allows tandem MS-based identification of RNAs in biological samples. Thus, the method presented here has broad potential for automated analysis of RNA; it complements conventional molecular biology-based techniques and is particularly suited for simultaneous analysis of the composition, structure, interaction, and dynamics of RNA and protein components in various cellular RNP complexes

Kosteneffiziente computergestützte Messwerterfassung im Physikunterricht

In der folgenden Arbeit geht es um die Erstellung von möglichst kostengünstigen Geräten zur Messwerterfassung im Physikunterricht. Es soll eine Bauanleitung für ein Messsystem zur Abstands- und Temperaturmessung mit einem Einplatinencomputer beschrieben werden. Um die Geräte im Schulunterricht zu testen, wurden zehn Prototypen gefertigt, sowie Unterrichtsmaterialien zu verschiedenen Experimenten erstellt. Die Einsatzfähigkeit der Geräte im Schulunterricht wurde durch eine Fallstudie in einem Gymnasium in Wien untersucht. Die Messwerterfassungssysteme wurden in drei Unterstufenklassen und einer Oberstufenklasse in insgesamt sieben Unterrichtseinheiten eingesetzt. Es nahmen 70 Schülerinnen und Schüler an der Untersuchung teil. Die Unterrichtsstunden wurden anhand von einem Schülerfragebogen, Videoanalyse, der Analyse von Schülerprotokollen und einem Lehrerinterview untersucht. Die Fallstudie bestätigt die Funktionalität und die Einsatzfähigkeit der Geräte im Physikunterricht.The following work is about creating low-cost devices for data acquisition in physics class. The thesis explains how to build a tool for measuring distance and temperature with a single-board computer. To test the devices in the classroom, ten prototyps and teaching materials for various experiments have been built. The usability of the devices in the classroom was examined by a case study in a high school in Vienna. 70 students out of four different grades participated in the study. The lessons were examined with reference to a student questionnaire, video analysis, analysis of student records and a teacher interview. The case study confirmed the functionality and usability of the devices for physics class

Overexpression of alpha-synuclein in oligodendrocytes does not increase susceptibility to focal striatal excitotoxicity

Contains fulltext : 152560.pdf (publisher's version ) (Open Access)BACKGROUND: Multiple system atrophy (MSA) is a fatal adult-onset neurodegenerative disease characterized by alpha-synuclein (alpha-syn) positive oligodendroglial cytoplasmic inclusions. The latter are associated with a neuronal multisystem neurodegeneration targeting central autonomic, olivopontocerebellar and striatonigral pathways, however the underlying mechanisms of neuronal cell death are poorly understood. Previous experiments have shown that oligodendroglial alpha-syn pathology increases the susceptibility to mitochondrial stress and proteasomal dysfunction leading to enhanced MSA-like neurodegeneration. Here we analyzed whether oligodendroglial alpha-syn overexpression in a transgenic mouse model of MSA synergistically interacts with focal neuronal excitotoxic damage generated by a striatal injection of quinolinic acid (QA) to affect the degree of striatal neuronal loss. RESULTS: QA injury led to comparable striatal neuronal loss and optical density of astro- and microgliosis in the striatum of transgenic and control mice. Respectively, no differences were identified in drug-induced rotation behavior or open field behavior between the groups. CONCLUSIONS: The failure of oligodendroglial alpha-syn pathology to exacerbate striatal neuronal loss resulting from QA excitotoxicity contrasts with enhanced striatal neurodegeneration due to oxidative or proteolytic stress, suggesting that enhanced vulnerability to excitotoxicity does not occur in oligodendroglial alpha-synucleinopathy like MSA