Alkali metal solutions in low-polarity solvents

Alkali metal solutions comprising alkali metal anions, the ‘alkalides’, and complexed alkali cations side by side provide a large untapped potential with respect to future applications. This is due to their unique properties such as a strongly reducing nature and a high polarizability. The use of organic complexing agents such as crown ethers and cryptands allows for the stabilization of high concentrations of charge carriers in a weakly polar medium. Nevertheless, the currently available knowledge about those solutions is very limited and their characterization is mostly centered around alkali metal NMR techniques. A significant upfield shift and exceptionally narrow width of the alkalide NMR signal were ascribed to the high shielding and high symmetry of an effectively unperturbed ‘gas-like’ anion in solution with little to no interaction with its local environment. Our investigations extend this traditional picture of the alkalide in solution and unveil the underlying effect of coulomb interactions on the properties of alkalides in low-polarity solvents by a comprehensive combination of spectroscopic methods. Concentration dependent measurement of both conductivity and permittivity of alkalide solutions revealed that ion pairing is a key factor in determining the kinetic properties and the stability of alkali metal solutions. Furthermore, the effect of dissolved metal on the mesoscopic structure of solutions of macrocyclic complexants was probed by small angle neutron scattering. Ultimately, we present a rationale for the rather obscure and unexpected temperature- and concentration-dependence of alkali metal dissolution in organic media and provide a multi-facetted understanding of the remarkable preparatory and spectroscopic characteristics of alkalide solutions. Finally, the synthesis of sterically congested amides and their unique fragmentation under dissolving metal reduction conditions are presented. Synthetic access to amide substrates was achieved by the use of highly electrophilic nitrimine precursors in the formation of imine intermediates.Open Acces

Integrative taxonomy on the fast track - towards more sustainability in biodiversity research

Background: A so called ``taxonomic impediment{''} has been recognized as a major obstacle to biodiversity research for the past two decades. Numerous remedies were then proposed. However, neither significant progress in terms of formal species descriptions, nor a minimum standard for descriptions have been achieved so far. Here, we analyze the problems of traditional taxonomy which often produces keys and descriptions of limited practical value. We suggest that phylogenetics and phenetics had a subtle and so far unnoticed effect on taxonomy leading to inflated species descriptions. Discussion: The term ``turbo-taxonomy{''} was recently coined for an approach combining cox1 sequences, concise morphological descriptions by an expert taxonomist, and high-resolution digital imaging to streamline the formal description of larger numbers of new species. We propose a further development of this approach which, together with open access web-publication and automated pushing of content from journal into a wiki, may create the most efficient and sustainable way to conduct taxonomy in the future. On demand, highly concise descriptions can be gradually updated or modified in the fully versioned wiki-framework we use. This means that the visibility of additional data is not compromised, while the original species description -the first version- remains preserved in the wiki, and of course in the journal version. A DNA sequence database with an identification engine replaces an identification key, helps to avoid synonyms and has the potential to detect grossly incorrect generic placements. We demonstrate the functionality of a species-description pipeline by naming 101 new species of hyperdiverse New Guinea Trigonopterus weevils in the open-access journal ZooKeys. Summary: Fast track taxonomy will not only increase speed, but also sustainability of global species inventories. It will be of great practical value to all the other disciplines that depend on a usable taxonomy and will change our perception of global biodiversity. While this approach is certainly not suitable for all taxa alike, it is the tool that will help to tackle many hyperdiverse groups and pave the road for more sustainable comparative studies, e.g. in community ecology, phylogeography and large scale biogeographic studies

Ninety-eight new species of Trigonopterus weevils from Sundaland and the Lesser Sunda Islands

The genus Trigonopterus Fauvel, 1862 is highly diverse in Melanesia. Only one species, Trigonopterus amphoralis Marshall, 1925 was so far recorded West of Wallace's Line (Eastern Sumatra). Based on focused field-work the fauna from Sundaland (Sumatra, Java, Bali, Palawan) and the Lesser Sunda Islands (Lombok, Sumbawa, Flores) is here revised. We redescribe T. amphoralis Marshall and describe an additional 98 new species: T. acuminatus sp. n.,T. aeneomicans sp. n.,T. alaspurwensis sp. n.,T. allopatricus sp. n.,T. allotopus sp. n.,T. angulicollis sp. n.,T. argopurensis sp. n.,T. arjunensis sp. n.,T. asper sp. n.,T. attenboroughi sp. n.,T. baliensis sp. n.,T. batukarensis sp. n.,T. bawangensis sp. n.,T. binodulus sp. n.,T. bornensis sp. n.,T. cahyoi sp. n.,T. costipennis sp. n.,T. cuprescens sp. n.,T. cupreus sp. n.,T. dacrycarpi sp. n.,T. delapan sp. n.,T. dentipes sp. n.,T. diengensis sp. n.,T. dimorphus sp. n.,T. disruptus sp. n.,T. dua sp. n.,T. duabelas sp. n.,T. echinatus sp. n.,T. empat sp. n.,T. enam sp. n.,T. fissitarsis sp. n.,T. florensis sp. n.,T. foveatus sp. n.,T. fulgidus sp. n.,T. gedensis sp. n.,T. halimunensis sp. n.,T. honjensis sp. n.,T. ijensis sp. n.,T. javensis sp. n.,T. kalimantanensis sp. n.,T. kintamanensis sp. n.,T. klatakanensis sp. n.,T. lampungensis sp. n.,T. latipes sp. n.,T. lima sp. n.,T. lombokensis sp. n.,T. merubetirensis sp. n.,T. mesehensis sp. n.,T. micans sp. n.,T. misellus sp. n.,T. palawanensis sp. n.,T. pangandaranensis sp. n.,T. paraflorensis sp. n.,T. pararugosus sp. n.,T. parasumbawensis sp. n.,T. pauxillus sp. n.,T. payungensis sp. n.,T. porcatus sp. n.,T. pseudoflorensis sp. n.,T. pseudosumbawensis sp. n.,T. punctatoseriatus sp. n.,T. ranakensis sp. n.,T. relictus sp. n.,T. rinjaniensis sp. n.,T. roensis sp. n.,T. rugosostriatus sp. n.,T. rugosus sp. n.,T. rutengensis sp. n.,T. saltator sp. n.,T. santubongensis sp. n.,T. sasak sp. n.,T. satu sp. n.,T. schulzi sp. n.,T. sebelas sp. n.,T. sembilan sp. n.,T. sepuluh sp. n.,T. seriatus sp. n.,T. serratifemur sp. n.,T. setifer sp. n.,T. silvestris sp. n.,T. singkawangensis sp. n.,T. singularis sp. n.,T. sinuatus sp. n.,T. squalidus sp. n.,T. sumatrensis sp. n.,T. sumbawensis sp. n.,T. sundaicus sp. n.,T. suturalis sp. n.,T. syarbis sp. n.,T. telagensis sp. n.,T. tepalensis sp. n.,T. tiga sp. n.,T. trigonopterus sp. n.,T. tujuh sp. n.,T. ujungkulonensis sp. n.,T. variolosus sp. n.,T. vulcanicus sp. n.,T. wallacei sp. n.. All new species are authored by the taxonomist-in-charge, Alexander Riedel. Most species belong to the litter fauna of primary wet evergreen forests. This habitat has become highly fragmented in the study area and many of its remnants harbor endemic species. Conservation measures should be intensified, especially in smaller and less famous sites to minimize the number of species threatened by extinction

Macroevolution of hyperdiverse flightless beetles reflects the complex geological history of the Sunda Arc

The Sunda Arc forms an almost continuous chain of islands and thus a potential dispersal corridor between mainland Southeast Asia and Melanesia. However, the Sunda Islands have rather different geological histories, which might have had an important impact on actual dispersal routes and community assembly. Here, we reveal the biogeographical history of hyperdiverse and flightless Trigonopterus weevils. Different approaches to ancestral area reconstruction suggest a complex east to west range expansion. Out of New Guinea, Trigonopterus repeatedly reached the Moluccas and Sulawesi transgressing Lydekker′s Line. Sulawesi repeatedly acted as colonization hub for different segments of the Sunda Arc. West Java, East Java and Bali are recognized as distinct biogeographic areas. The timing and diversification of species largely coincides with the geological chronology of island emergence. Colonization was not inhibited by traditional biogeographical boundaries such as Wallace’s Line. Rather, colonization patterns support distance dependent dispersal and island age limiting dispersal

Triphenylene-Derived Electron Acceptors and Donors on Ag(111):Formation of Intermolecular Charge-Transfer Complexes with Common Unoccupied Molecular States

Over the past years, ultrathin films consisting of electron donating and accepting molecules have attracted increasing attention due to their potential usage in optoelectronic devices. Key parameters for understanding and tuning their performance are intermolecular and molecule–substrate interactions. Here, the formation of a monolayer thick blend of triphenylene‐based organic donor and acceptor molecules from 2,3,6,7,10,11‐hexamethoxytriphenylene (HAT) and 1,4,5,8,9,12‐hexaazatriphenylenehexacarbonitrile (HATCN), respectively, on a silver (111) surface is reported. Scanning tunneling microscopy and spectroscopy, valence and core level photoelectron spectroscopy, as well as low‐energy electron diffraction measurements are used, complemented by density functional theory calculations, to investigate both the electronic and structural properties of the homomolecular as well as the intermixed layers. The donor molecules are weakly interacting with the Ag(111) surface, while the acceptor molecules show a strong interaction with the substrate leading to charge transfer and substantial buckling of the top silver layer and of the adsorbates. Upon mixing acceptor and donor molecules, strong hybridization occurs between the two different molecules leading to the emergence of a common unoccupied molecular orbital located at both the donor and acceptor molecules. The donor acceptor blend studied here is, therefore, a compelling candidate for organic electronics based on self‐assembled charge‐transfer complexes

DNA Barcoding for Community Ecology - How to Tackle a Hyperdiverse, Mostly Undescribed Melanesian Fauna

Trigonopterus weevils are widely distributed throughout Melanesia and hyperdiverse in New Guinea. They are a dominant feature in natural forests, with narrow altitudinal zonation. Their use in community ecology has been precluded by the "taxonomic impediment". We sampled >6,500 specimens from seven areas across New Guinea; 1,002 specimens assigned to 270 morphospecies were DNA sequenced. Objective clustering of a refined dataset (excluding nine cryptic species) at 3% threshold revealed 324 genetic clusters (DNA group count relative to number of morphospecies = 20.0% overestimation of species diversity, or 120.0% agreement) and 85.6% taxonomic accuracy (the proportion of DNA groups that "perfectly" agree with morphology-based species hypotheses). Agreement and accuracy were best at an 8% threshold. GMYC analysis revealed 328 entities (21.5% overestimation) with 227 perfect GMYC entities (84.1% taxonomic accuracy). Both methods outperform the parataxonomist (19% underestimation; 31.6% taxonomic accuracy). The number of species found in more than one sampling area was highest in the Eastern Highlands and Huon (Sørensen similarity index 0.07, 4 shared species); ⅓ of all areas had no species overlap. Success rates of DNA barcoding methods were lowest when species showed a pronounced geographical structure. In general, Trigonopterus show high α and β-diversity across New Guinea. DNA barcoding is an excellent tool for biodiversity surveys but success rates might drop when closer localities are included. Hyperdiverse Trigonopterus are a useful taxon for evaluating forest remnants in Melanesia, allowing finer-grained analyses than would be possible with vertebrate taxa commonly used to date. Our protocol should help establish other groups of hyperdiverse fauna as target taxa for community ecology. Sequencing delivers objective data on taxa of incredible diversity but mostly without a solid taxonomic foundation and should help pave the road for the eventual formal naming of new species

The Solar Neighborhood. XXII. Parallax Results from the CTIOPI 0.9m Program: Trigonometric Parallaxes of 64 Nearby Systems with 0\farcs5 ≤μ≤\leq \mu \leq 1\farcs0 yr−1^{-1} (SLOWMO sample)

We present trigonometric parallaxes of 64 stellar systems with proper motions between 0\farcs5 yr$^{-1}$ and 1\farcs0 yr$^{-1}$ from the ongoing RECONS (Research Consortium On Nearby Stars) parallax program at CTIO (the Cerro Tololo Interamerican Observatory). All of the systems are south of DEC $= +30$, and 58 had no previous trigonometric parallaxes. In addition to parallaxes for the systems, we present proper motions, Johnson-Kron-Cousins $VRI$ photometry, variability measurements, and spectral types. Nine of the systems are multiple; we present results for their components, three of which are new astrometric detections. Of the 64 systems, 56 are within 25 parsecs of the Sun and 52 of those are in the southern hemisphere, comprising 5.7\% of the total number of known southern 25 parsec systems.Comment: Figures not inline. Accepted by A

ARTEFACTS: How do we want to deal with the future of our one and only planet?

The European Commission’s Science and Knowledge Service, the Joint Research Centre (JRC), decided to try working hand-in-hand with leading European science centres and museums. Behind this decision was the idea that the JRC could better support EU Institutions in engaging with the European public. The fact that European Union policies are firmly based on scientific evidence is a strong message which the JRC is uniquely able to illustrate. Such a collaboration would not only provide a platform to explain the benefits of EU policies to our daily lives but also provide an opportunity for European citizens to engage by taking a more active part in the EU policy making process for the future. A PILOT PROGRAMME To test the idea, the JRC launched an experimental programme to work with science museums: a perfect partner for three compelling reasons. Firstly, they attract a large and growing number of visitors. Leading science museums in Europe have typically 500 000 visitors per year. Furthermore, they are based in large European cities and attract local visitors as well as tourists from across Europe and beyond. The second reason for working with museums is that they have mastered the art of how to communicate key elements of sophisticated arguments across to the public and making complex topics of public interest readily accessible. That is a high-value added skill and a crucial part of the valorisation of public-funded research, never to be underestimated. Finally museums are, at present, undergoing something of a renaissance. Museums today are vibrant environments offering new techniques and technologies to both inform and entertain, and attract visitors of all demographics.JRC.H.2-Knowledge Management Methodologies, Communities and Disseminatio

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

The James Webb Space Telescope Mission

Twenty-six years ago a small committee report, building on earlier studies, expounded a compelling and poetic vision for the future of astronomy, calling for an infrared-optimized space telescope with an aperture of at least $4m$. With the support of their governments in the US, Europe, and Canada, 20,000 people realized that vision as the $6.5m$ James Webb Space Telescope. A generation of astronomers will celebrate their accomplishments for the life of the mission, potentially as long as 20 years, and beyond. This report and the scientific discoveries that follow are extended thank-you notes to the 20,000 team members. The telescope is working perfectly, with much better image quality than expected. In this and accompanying papers, we give a brief history, describe the observatory, outline its objectives and current observing program, and discuss the inventions and people who made it possible. We cite detailed reports on the design and the measured performance on orbit.Comment: Accepted by PASP for the special issue on The James Webb Space Telescope Overview, 29 pages, 4 figure