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Schneider K.A.,Mittweida University of Applied Sciences | Schneider K.A.,University of Vienna | Escalante A.A.,Arizona State University
Malaria Journal | Year: 2013

Background: Considering the distinct biological characteristics of Plasmodium species is crucial for control and elimination efforts, in particular when facing the spread of drug resistance. Whereas the evolutionary fitness of all malarial species could be approximated by the probability of being taken by a mosquito and then infecting a new host, the actual steps in the malaria life cycle leading to a successful transmission event show differences among Plasmodium species. These "steps" are called fitness components. Differences in terms of fitness components may affect how selection imposed by interventions, e.g. drug treatments, differentially acts on each Plasmodium species. Thus, a successful malaria control or elimination programme should understand how differences in fitness components among different malaria species could affect adaptive evolution (e.g. the emergence of drug resistance). In this investigation, the interactions between some fitness components and natural selection are explored. Methods. A population-genetic model is formulated that qualitatively explains how different fitness components (in particular gametocytogenesis and longevity of gametocytes) affect selection acting on merozoites during the erythrocytic cycle. By comparing Plasmodium falciparum and Plasmodium vivax, the interplay of parasitaemia and gametocytaemia dynamics in determining fitness is modelled under circumstances that allow contrasting solely the differences between these two parasites in terms of their fitness components. Results: By simulating fitness components, it is shown that selection acting on merozoites (e.g., on drug resistant mutations or malaria antigens) is more efficient in P. falciparum than in P. vivax. These results could explain, at least in part, why resistance against drugs, such as chloroquine (CQ) is highly prevalent in P. falciparum worldwide, while CQ is still a successful treatment for P. vivax despite its massive use. Furthermore, these analyses are used to explore the importance of understanding the dynamic of gametocytaemia to ascertain the spreading of drug resistance. Conclusions: The strength of natural selection on mutations that express their advantage at the merozoite stage is different in P. vivax and P. falciparum. Species-specific differences in gametocytogenesis and longevity of gametocytes need to be accounted for when designing effective malaria control and elimination programmes. There is a need for reliable data on gametocytogenesis from field studies. © 2013 Schneider and Escalante; licensee BioMed Central Ltd. Source


Andreopoulos B.,TU Dresden | Labudde D.,Mittweida University of Applied Sciences
Algorithms for Molecular Biology | Year: 2011

Background: Single-molecule force spectroscopy (SMFS) is a technique that measures the force necessary to unfold a protein. SMFS experiments generate Force-Distance (F-D) curves. A statistical analysis of a set of F-D curves reveals different unfolding pathways. Information on protein structure, conformation, functional states, and inter- and intra-molecular interactions can be derived.Results: In the present work, we propose a pattern recognition algorithm and apply our algorithm to datasets from SMFS experiments on the membrane protein bacterioRhodopsin (bR). We discuss the unfolding pathways found in bR, which are characterised by main peaks and side peaks. A main peak is the result of the pairwise unfolding of the transmembrane helices. In contrast, a side peak is an unfolding event in the alpha-helix or other secondary structural element. The algorithm is capable of detecting side peaks along with main peaks.Therefore, we can detect the individual unfolding pathway as the sequence of events labeled with their occurrences and co-occurrences special to bR's unfolding pathway. We find that side peaks do not co-occur with one another in curves as frequently as main peaks do, which may imply a synergistic effect occurring between helices. While main peaks co-occur as pairs in at least 50% of curves, the side peaks co-occur with one another in less than 10% of curves. Moreover, the algorithm runtime scales well as the dataset size increases.Conclusions: Our algorithm satisfies the requirements of an automated methodology that combines high accuracy with efficiency in analyzing SMFS datasets. The algorithm tackles the force spectroscopy analysis bottleneck leading to more consistent and reproducible results. © 2011 Andreopoulos and Labudde; licensee BioMed Central Ltd. Source


Patent
Mittweida University of Applied Sciences | Date: 2012-02-09

The invention relates to methods and devices for breaking up ore. The methods and devices are characterised in particular in that ore mineral or ore minerals can be subsequently easily extracted. For this purpose coherent NIR radiation, non-coherent NIR radiation, at least one electric alternating field having a frequency greater than 300 GHz, at least one magnetic alternating field having a frequency greater than 300 GHz, at least one electromagnetic alternating field having a frequency greater than 300 GHz, or a combination thereof are respectively applied to the ore at least once by means of a device for generating the radiation, the at least one alternating field, or the radiation and the at least one alternating field, wherein ore mineral, ore minerals, absorbent components, or ore minerals and absorbent components of the ore absorb(s) energy from the radiation, the alternating field, or the radiation and the alternating field and said energy is not or is only slightly absorbed by the lode matter. Thus, advantageously, cracks are formed in the ore or the ore splits by means of the resulting stresses.


Grant
Agency: Cordis | Branch: FP7 | Program: CP | Phase: ENERGY.2012.10.2.1 | Award Amount: 3.91M | Year: 2012

CyanoFactory brings together ten selected leading, highly complementary European partners with the aim to carry out integrated, fundamental research aiming at applying synthetic biology principles towards a cell factory notion in microbial biotechnology. The vision is to build on recent progress in synthetic biology and develop novel photosynthetic cyanobacteria as chassis to be used as self-sustained cell factories in generating a solar fuel. This will include the development of a toolbox with orthogonal parts and devices for cyanobacterial synthetic biology, improvement of the chassis enabling enhanced growth and robustness in challenging environmental conditions, establishment of a data warehouse facilitating the modelling and optimization of cyanobacterial metabolic pathways, and strong and novel bioinformatics for effective data mining. To reach the goal, a combination of basic and applied R&D is needed; basic research to design and construct the cyanobacterial cells efficiently evolving H2 from the endless resources solar energy and water, and applied research to design and construct the advanced photobioreactors that efficiently produce H2. Biosafety is of highest concern and dedicated efforts will be made to address and control cell survival and death. The aim, to develop a (photo)synthetic cell factory, will have an enormous impact on the future options and possibilities for renewable solar fuel production. The consortium includes academic, research institute and industry participants with the direct involvement of two SMEs in the advanced photobioreactor design, construction and use. Purpose-designed, specifically engineered self-sustained cells utilising solar energy and CO2 from the air, may be the mechanisms and processes by which we generate large scale renewable energy carriers in our future societies. CyanoFactory offers Europe the possibility to take a lead, and not only follow, in these very important future and emerging technologies!


Chenet S.M.,Arizona State University | Schneider K.A.,Mittweida University of Applied Sciences | Schneider K.A.,University of Vienna | Villegas L.,ICF International | Escalante A.A.,Arizona State University
Malaria Journal | Year: 2012

Background: Regardless of the growing interest in detecting population structures in malarial parasites, there have been limited discussions on how to use this concept in control programmes. In such context, the effects of the parasite population structures will depend on interventions' spatial or temporal scales. This investigation explores the problem of identifying genetic markers, in this case microsatellites, to unveil Plasmodium genetic structures that could affect decisions in the context of elimination. The study was performed in a low-transmission area, which offers a good proxy to better understand problems associated with surveillance at the final stages of malaria elimination. Methods. Plasmodium vivax samples collected in Tumeremo, Venezuela, between March 2003 and November 2004 were analysed. Since Plasmodium falciparum also circulates in many low endemic areas, P. falciparum samples from the same locality and time period were included for comparison. Plasmodium vivax samples were assayed for an original set of 25 microsatellites and P. falciparum samples were assayed for 12 microsatellites. Results: Not all microsatellite loci assayed offered reliable local data. A complex temporal-cluster dynamics is found in both P. vivax and P. falciparum. Such dynamics affect the numbers and the type of microsatellites required for identifying individual parasites or parasite clusters when performing cross-sectional studies. The minimum number of microsatellites required to differentiate circulating P. vivax clusters differs from the minimum number of hyper-variable microsatellites required to distinguish individuals within these clusters. Regardless the extended number of microsatellites used in P. vivax, it was not possible to separate all individual infections. Conclusions: Molecular surveillance has great potential; however, it requires preliminary local studies in order to properly interpret the emerging patterns in the context of elimination. Clonal expansions and clusters turnovers need to be taken into account when using molecular markers. Those affect the number and type of microsatellite markers, as well as, the expected genetic patterns in the context of operational investigations. By considering the local dynamics, elimination programmes could cost-effectively use molecular markers. However, population level studies need to consider the local limitations of a given set of loci in terms of providing epidemiologically relevant information. © 2012 Chenet et al.; licensee BioMed Central Ltd. Source

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