Evaluation of macrophyte control in 38 Florida lakes using triploid grass carp

Florida’s large number of shallow lakes, warm climate and long growing season have contributed to the development of excessive growths of aquatic macrophytes that have seriously interfered with many water use activities. The introduction of exotic aquatic macrophyte species such as hydrilla ( Hydrilla verticillata ) have added significantly to aquatic plant problems in Florida lakes. The use of grass carp ( Ctenopharyngodon idella ) can be an effective and economical control for aquatic vegetation such as hydrilla. Early stocking rates (24 to 74 grass carp per hectare of lake area) resulted in grass carp consumption rates that vastly exceeded the growth rates of the aquatic plants and often resulted in the total loss of all submersed vegetation. This study looked at 38 Florida lakes that had been stocked with grass carp for 3 to 10 years with stocking rates ranging from < 1 to 59 grass carp per hectare of lake and 1 to 207 grass carp per hectare of vegetation to determine the long term effects of grass carp on aquatic macrophyte communities. The median PAC (percent area coverage) value of aquatic macrophytes for the study lakes after they were stocked with grass carp was 14% and the median PVI (percent volume infested) value of aquatic macrophytes was 2%. Only lakes stocked with less than 25 to 30 fish per hectare of vegetation tended to have higher than median PAC and PVI values. When grass carp are stocked at levels of > 25 to 30 fish per hectare of vegetation the complete control of aquatic vegetation can be achieved, with the exception of a few species of plants that grass carp have extreme difficulty consuming. If the management goal for a lake is to control some of the problem aquatic plants while maintaining a small population of predominately unpalatable aquatic plants, grass carp can be stocked at approximately 25 to 30 fish per hectare of vegetation

Nutrient Limitation of Periphyton in a Spring-Fed, Coastal Stream in Florida, USA.

There is strong evidence to suggest that ground-water nitrate concentrations have increased in recent years and further increases are expected along portions of the central Gulf coast of Florida. Much of the nitrate enriched groundwater is discharged into surface waters through numerous freshwater springs that are characteristic of the area and the potential for eutrophication of their receiving waters is a legitimate concern. To test the potential effects of elevated nutrient concentrations on the periphyton community an in situ nutrient addition experiment was conducted in the spring-fed Chassahowitzka River, FL, USA, during the summer of 1999. Plastic tubes housing arrays of glass microscope slides were suspended in the stream. Periphyton colonizing the microscope slides was subjected to artificial increases in nitrogen, phosphorus or a combination of both. Slides from each tube were collected at 3- to 4- day intervals and the periphyton communities were measured for chlorophyll concentration. The addition of approximately 10 μg/L of phosphate above ambient concentrations significantly increased the amount of periphyton on artificial substrates relative to controls; the addition of approximately 100 μg/L of nitrate above ambient concentrations did not. The findings from this experiment implicated phosphorus, rather than nitrogen, as the nutrient that potentially limits periphyton growth in this system.(PDF contains 4 pages.

Rapid self-assembly of α-synuclein observed by in situ atomic force microscopy

Self-assembly of α−synuclein resulting in protein aggregates of diverse morphology has been implicated in the pathogenesis of Parkinson’s disease and other neurodegenerative disorders known as synucleinopathies. Apart from its biomedical relevance, this aggregation process is representative of the interconversion of an unfolded protein into nanostructures with typical amyloid features. We have used in situ tapping mode atomic force microscopy (AFM) to continuously monitor the self-assembly of wild-type α-synuclein, its disease-related mutants A30P and A53T, and the C-terminally truncated variant α-synuclein(1-108). Different aggregation modes were observed depending on experimental conditions, i.e. pH, protein concentration, polyamine concentration, temperature and the supporting substrate. At pH 7.5, in the absence of the biogenic polyamines spermidine or spermine, elongated sheets 1.1(±0.2)nm in height and presumably representing individual β-sheet structures, were formed on mica substrates within a few minutes. Their orientation was directed by the crystalline substructure of the substrate. In contrast, sheet formation was not observed with hydrophobic highly oriented pyrolytic graphite (HOPG) substrates, suggesting that negatively charged surfaces promote α-synuclein self-assembly. In the presence of spermidine or spermine 5.9(±1.0) nm high spheroidal structures were preferentially formed, sharing characteristics with similar structures previously reported for several amyloidogenic proteins and linked to neurotoxicity. Alpha-synuclein spheroid formation depended critically on polyamine binding to the Cterminus, revealing a promoting effect of the C-terminus on α-synuclein assembly in the bound state. In rare cases, fibril growth from spheroids or preformed aggregates was observed. At pH 5.0, fibrils were formed initially and incorporated into amorphous aggregates in the course of the aggregation process, providing evidence for the potential of amyloid fibril surfaces to act as nucleation sites in amorphous aggregation. This study provides a direct insight into different modes of α-synuclein self-assembly and identifies key factors modulating the aggregation process

Photoluminescence and Terahertz Emission from Femtosecond Laser-Induced Plasma Channels

Luminescence as a mechanism for terahertz emission from femtosecond laser-induced plasmas is studied. By using a fully microscopic theory, Coulomb scattering between electrons and ions is shown to lead to luminescence even for a spatially homogeneous plasma. The spectral features introduced by the rod geometry of laser-induced plasma channels in air are discussed on the basis of a generalized mode-function analysis.Comment: 4 pages with 2 figures

An infrared study of the double nucleus in NGC3256

We present new resolved near and mid-IR imaging and N-band spectroscopy of the two nuclei in the merger system NGCA3256, the most IR luminous galaxy in the nearby universe. The results from the SED fit to the data are consistent with previous estimates of the amount of obscuration towards the nuclei and the nuclear star formation rates. However, we also find substantial differences in the infrared emission from the two nuclei which cannot be explained by obscuration alone. We conclude that the northern nucleus requires an additional component of warm dust in order to explain its properties. This suggests that local starforming conditions can vary significantly within the environment of a single system.Comment: Accepted for publication (MNRAS

Kunst und Kunstgeschichte in der deutschen Tagespresse 1950 - 2000

In dieser Dissertation wird untersucht, wie Themen rund um Kunst und Kunstgeschichte in der deutschen Tagespresse dargestellt werden. Anhand einer Untersuchung der vier bedeutendsten Zeitungen Deutschlands, der Frankfurter Allgemeinen Zeitung, der Frankfurter Rundschau, der Süddeutschen Zeitung und der Welt, wird aufgezeigt, welche Entwicklung das kunstgeschichtliche Feuilleton im Zeitraum von 1950 bis 2000 nimmt. In diesem Zusammenhang werden quantitative und qualitative Unterschiede und somit die den Leser am effektivsten informierende Zeitung ausgemacht. Zudem wird der Blick auf die ausländischen Feuilletons und auf die Erfahrungen eines Kunstredakteurs gelenkt. In ausgesuchten Jahrgängen wird dokumentiert, auf welch mannigfaltige Weise eine Zeitung informieren kann und welche Rolle die Kunst im deutschen Feuilleton spielt

Quality of Web Mashups: A Systematic Mapping Study

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-319-04244-2_8Web mashups are a new generation of applications based on the composition of ready-to-use, heterogeneous components. They are gaining momentum thanks to their lightweight composition approach, which represents a new opportunity for companies to leverage on past investments in SOA, Web services, and public APIs. Although several studies are emerging in order to address mashup development, no systematic mapping studies have been reported on how quality issues are being addressed. This paper reports a systematic mapping study on which and how the quality of Web mashups has been addressed and how the product quality-aware approaches have been defined and validated. The aim of this study is to provide a background in which to appropriately develop future research activities. A total of 38 research papers have been included from an initial set of 187 papers. Our results provided some findings regarding how the most relevant product quality characteristics have been addressed in different artifacts and stages of the development process. They have also been useful to detect some research gaps, such as the need of more controlled experiments and more quality-aware mashup development proposals for other characteristics which being important for the Web domain have been neglected such as Usability and ReliabilityThis work is funded by the MULTIPLE project (TIN2009-13838), the Senescyt program (scholarships 2011), and the Erasmus Mundus Programme of the European Commission under the Transatlantic Partnership for Excellence in Engineering - TEE Project.Cedillo Orellana, IP.; Fernández Martínez, A.; Insfrán Pelozo, CE.; Abrahao Gonzales, SM. (2013). Quality of Web Mashups: A Systematic Mapping Study. En Current Trends in Web Engineering. Springer. 66-78. https://doi.org/10.1007/978-3-319-04244-2_8S6678Alkhalifa, E.: The Future of Enterprise Mashups. Business Insights. E-Strategies for Resource Management Systems (2009)Beemer, B., Gregg, D.: Mashups: A Literature Review and Classification Framework. Future Internet 1, 59–87 (2009)Cappiello, C., Daniel, F., Matera, M.: A Quality Model for Mashup Components. In: Gaedke, M., Grossniklaus, M., Díaz, O. (eds.) ICWE 2009. LNCS, vol. 5648, pp. 236–250. Springer, Heidelberg (2009)Cappiello, C., Daniel, F., Matera, M., Pautasso, C.: Information Quality in Mashups. IEEE Internet Computing 14(4), 32–40 (2010)Cappiello, C., Matera, M., Picozzi, M., Daniel, F., Fernandez, A.: Quality-Aware Mashup Composition: Issues, Techniques and Tools. In: 8th International Conference on the Quality of Information and Communications Technology (QUATIC 2012), pp. 10–19 (2012)Fenton, N.E., Pfleeger, S.L.: Software Metrics: A Rigorous and Practical Approach, 2nd edn. International Thompson 1996, pp. I–XII, 1–638 (1996) ISBN 978-1-85032-275-7Fernandez, A., Insfran, E., Abrahão, S.: Usability evaluation methods for the web: A systematic mapping study. Information and Software Technology 53(8), 789–817 (2011)Garousi, V., Mesbah, A., Betin-Can, A., Mirshokraie, S.: A systematic mapping study of web application testing. Information and Software Technology 55(8), 1374–1396 (2013)Grammel, L., Storey, M.-A.: A survey of mashup development environments. In: Chignell, M., Cordy, J., Ng, J., Yesha, Y. (eds.) The Smart Internet. LNCS, vol. 6400, pp. 137–151. Springer, Heidelberg (2010)Hoyer, V., Fischer, M.: Market Overview of Enterprise Mashup Tools. In: Bouguettaya, A., Krueger, I., Margaria, T. (eds.) ICSOC 2008. LNCS, vol. 5364, pp. 708–721. Springer, Heidelberg (2008)ISO/IEC: ISO/IEC 25010 Systems and software engineering. Systems and software Quality Requirements and Evaluation (SQuaRE). System and software quality models (2011)Kitchenham, B., Charters, S.: Guidelines for performing Systematic Literature Reviews in Software Engineering. Version 2.3, ESBE Technical Report, Keele University, UK (2007)Mendes, E.: A systematic review on the Web engineering research. In: International Symposium on Empirical Software Engineering (ISESE 2005), pp. 498–507 (2005)OrangeLabs: State of the Art in Mashup tools, SocEDA project, pp. 1–59 (2011)Petersen, K., Feldt, R., Mujtaba, S., Mattsson, M.: Systematic mapping studies in software engineering. In: 12th International Conference on Evaluation and Assessment in Software Engineering (EASE), pp. 68–77 (2008)Raza, M., Hussain, F.K., Chang, E.: A methodology for quality-based mashup of data sources. In: 10th International Conference on Information Integration and Web-based Applications & Services (iiWAS 2008), pp. 528–533 (2008)Saeed, A.: A Quality-based Framework for Leveraging the Process of Mashup Component Selection (2009), https://gupea.ub.gu.se/handle/2077/21953Sharma, A., Hellmann, T.D., Maurer, F.: Testing of Web Services - A Systematic Mapping. In: 8th World Congress on Services (SERVICES 2012), pp. 346–352 (2012