73 research outputs found
Revolutionizing scientific communication and collaboration
This presentation introduces new web-based ways of scientific communication and collaboration. It focuses on wikis and the _First Online EMBL PhD Symposium_ as an example of an online conference
A quick trip through openness, freedom and transparency
This talk aims to give scientists an introduction to the concepts of openness, freedom and transparency and their applications (not only) for science. It covers the topics of open source, open formats, Creative Commons, open access, and open science/knowledge. A video of the talk is available on the author's website.

The What, Why and How of openness in science
We give a short introduction to open science followed by an overview of Creative Commons and open source licenses
Gene autoregulation by 3' UTR-derived bacterial small RNAs
Negative feedback regulation, that is the ability of a gene to repress its own synthesis, is the most abundant regulatory motif known to biology. Frequently reported for transcriptional regulators, negative feedback control relies on binding of a transcription factor to its own promoter. Here, we report a novel mechanism for gene autoregulation in bacteria relying on small regulatory RNA (sRNA) and the major endoribonuclease, RNase E. TIER-seq analysis (transiently-inactivating-an-endoribonuclease-followed-by-RNA-seq) revealed similar to 25,000 RNase E-dependent cleavage sites in Vibrio cholerae, several of which resulted in the accumulation of stable sRNAs. Focusing on two examples, OppZ and CarZ, we discovered that these sRNAs are processed from the 3' untranslated region (3' UTR) of the oppABCDF and carAB operons, respectively, and basepair with their own transcripts to inhibit translation. For OppZ, this process also triggers Rho-dependent transcription termination. Our data show that sRNAs from 3' UTRs serve as autoregulatory elements allowing negative feedback control at the post-transcriptional level
A computational screen for type I polyketide synthases in metagenomics shotgun data
BACKGROUND: Polyketides are a diverse group of biotechnologically important secondary metabolites that are produced by multi domain enzymes called polyketide synthases (PKS). METHODOLOGY/PRINCIPAL FINDINGS: We have estimated frequencies of type I PKS (PKS I) – a PKS subgroup – in natural environments by using Hidden-Markov-Models of eight domains to screen predicted proteins from six metagenomic shotgun data sets. As the complex PKS I have similarities to other multi-domain enzymes (like those for the fatty acid biosynthesis) we increased the reliability and resolution of the dataset by maximum-likelihood trees. The combined information of these trees was then used to discriminate true PKS I domains from evolutionary related but functionally different ones. We were able to identify numerous novel PKS I proteins, the highest density of which was found in Minnesota farm soil with 136 proteins out of 183,536 predicted genes. We also applied the protocol to UniRef database to improve the annotation of proteins with so far unknown function and identified some new instances of horizontal gene transfer. CONCLUSIONS/SIGNIFICANCE: The screening approach proved powerful in identifying PKS I sequences in large sequence data sets and is applicable to many other protein families
Fundamental Physics with the Laser Astrometric Test Of Relativity
The Laser Astrometric Test Of Relativity (LATOR) is a joint European-U.S.
Michelson-Morley-type experiment designed to test the pure tensor metric nature
of gravitation - a fundamental postulate of Einstein's theory of general
relativity. By using a combination of independent time-series of highly
accurate gravitational deflection of light in the immediate proximity to the
Sun, along with measurements of the Shapiro time delay on interplanetary scales
(to a precision respectively better than 0.1 picoradians and 1 cm), LATOR will
significantly improve our knowledge of relativistic gravity. The primary
mission objective is to i) measure the key post-Newtonian Eddington parameter
\gamma with accuracy of a part in 10^9. (1-\gamma) is a direct measure for
presence of a new interaction in gravitational theory, and, in its search,
LATOR goes a factor 30,000 beyond the present best result, Cassini's 2003 test.
The mission will also provide: ii) first measurement of gravity's non-linear
effects on light to ~0.01% accuracy; including both the Eddington \beta
parameter and also the spatial metric's 2nd order potential contribution (never
measured before); iii) direct measurement of the solar quadrupole moment J2
(currently unavailable) to accuracy of a part in 200 of its expected size; iv)
direct measurement of the "frame-dragging" effect on light by the Sun's
gravitomagnetic field, to 1% accuracy. LATOR's primary measurement pushes to
unprecedented accuracy the search for cosmologically relevant scalar-tensor
theories of gravity by looking for a remnant scalar field in today's solar
system. We discuss the mission design of this proposed experiment.Comment: 8 pages, 9 figures; invited talk given at the 2005 ESLAB Symposium
"Trends in Space Science and Cosmic Vision 2020," 19-21 April 2005, ESTEC,
Noodrwijk, The Netherland
A Mission to Explore the Pioneer Anomaly
The Pioneer 10 and 11 spacecraft yielded the most precise navigation in deep
space to date. These spacecraft had exceptional acceleration sensitivity.
However, analysis of their radio-metric tracking data has consistently
indicated that at heliocentric distances of astronomical units,
the orbit determinations indicated the presence of a small, anomalous, Doppler
frequency drift. The drift is a blue-shift, uniformly changing with a rate of
Hz/s, which can be interpreted as a
constant sunward acceleration of each particular spacecraft of . This signal has become known as the Pioneer
anomaly. The inability to explain the anomalous behavior of the Pioneers with
conventional physics has contributed to growing discussion about its origin.
There is now an increasing number of proposals that attempt to explain the
anomaly outside conventional physics. This progress emphasizes the need for a
new experiment to explore the detected signal. Furthermore, the recent
extensive efforts led to the conclusion that only a dedicated experiment could
ultimately determine the nature of the found signal. We discuss the Pioneer
anomaly and present the next steps towards an understanding of its origin. We
specifically focus on the development of a mission to explore the Pioneer
Anomaly in a dedicated experiment conducted in deep space.Comment: 8 pages, 9 figures; invited talk given at the 2005 ESLAB Symposium
"Trends in Space Science and Cosmic Vision 2020", 19-21 April 2005, ESTEC,
Noordwijk, The Netherland
Sustainable Innovation in a Multi-University Master Course
Mobility, multi-locality, and transnational migration are current social developments among the population of the European Union. These social developments in society and companies, linked to the challenges of sustainability, lead to new requirements for working in the European Union. Teaching and learning in higher education needs to adapt to these requirements. As a result, new and innovative teaching and learning practices in higher education should provide competencies for transnational teamwork in the curriculum of tomorrow's engineers in order to ensure their competitiveness in the job market and advantage in their future careers. Thirteen European students from four countries participated in a new project-based course, called the "European Engineering Team". Students focused on the development of two innovative and sustainable products. The goal of this paper is to present the thermal pallet cover, which is the result of the first one-year transnational and sustainability-oriented project. This paper also aims to present the process of performing the project. It provides the overview and discussion of engineering and management tasks that students completed in the transnational environment, working remotely at their own campuses between scheduled transnational meetings. The work contributes to project-oriented learning that may constitute a basis for teaching holistic engineering courses at mechanical and industrial engineering departments
A Nitrile Hydratase in the Eukaryote Monosiga brevicollis
Bacterial nitrile hydratase (NHases) are important industrial catalysts and waste water remediation tools. In a global computational screening of conventional and metagenomic sequence data for NHases, we detected the two usually separated NHase subunits fused in one protein of the choanoflagellate Monosiga brevicollis, a recently sequenced unicellular model organism from the closest sister group of Metazoa. This is the first time that an NHase is found in eukaryotes and the first time it is observed as a fusion protein. The presence of an intron, subunit fusion and expressed sequence tags covering parts of the gene exclude contamination and suggest a functional gene. Phylogenetic analyses and genomic context imply a probable ancient horizontal gene transfer (HGT) from proteobacteria. The newly discovered NHase might open biotechnological routes due to its unconventional structure, its new type of host and its apparent integration into eukaryotic protein networks
Catalytic Transformations of Alkynes via Ruthenium Vinylidene and Allenylidene Intermediates
NOTICE: This is the peer reviewed version of the following book chapter: Varela J. A., González-Rodríguez C., Saá C. (2014). Catalytic Transformations of Alkynes via Ruthenium Vinylidene and Allenylidene Intermediates. In: Dixneuf P., Bruneau C. (eds) Ruthenium in Catalysis. Topics in Organometallic Chemistry, vol 48, pp. 237-287. Springer, Cham. [doi: 10.1007/3418_2014_81]. This article may be used for non-commercial purposes in accordance with Springer Verlag Terms and Conditions for self-archiving.Vinylidenes are high-energy tautomers of terminal alkynes and they can be stabilized by coordination with transition metals. The resulting metal-vinylidene species have interesting chemical properties that make their reactivity different to that of the free and metal π-coordinated alkynes: the carbon α to the metal is electrophilic whereas the β carbon is nucleophilic. Ruthenium is one of the most commonly used transition metals to stabilize vinylidenes and the resulting species can undergo a range of useful transformations. The most remarkable transformations are the regioselective anti-Markovnikov addition of different nucleophiles to catalytic ruthenium vinylidenes and the participation of the π system of catalytic ruthenium vinylidenes in pericyclic reactions. Ruthenium vinylidenes have also been employed as precatalysts in ring closing metathesis (RCM) or ring opening metathesis polymerization (ROMP).
Allenylidenes could be considered as divalent radicals derived from allenes. In a similar way to vinylidenes, allenylidenes can be stabilized by coordination with transition metals and again ruthenium is one of the most widely used metals. Metalallenylidene complexes can be easily obtained from terminal propargylic alcohols by dehydration of the initially formed metal-hydroxyvinylidenes, in which the reactivity of these metal complexes is based on the electrophilic nature of Cα and Cγ, while Cβ is nucleophilic. Catalytic processes based on nucleophilic additions and pericyclic reactions involving the π system of ruthenium allenylidenes afford interesting new structures with high selectivity and atom economy
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