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Nature
Nature is a weekly international journal publishing the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature also provides rapid, authoritative, insightful and arresting news and interpretation of topical and coming trends affecting science, scientists and the wider public.

Nature
  • Making the paper: David Bartel & Nikolaus Rajewsky
    RNA fragments tune the production of thousands of cellular proteins.

  • Abstractions
    First authorTropical cyclones go by many names ? hurricanes, typhoons and tropical storms, as well as human names such as Katrina and Albert. Worldwide, there is an average of 86 such storms a year, more than half of which reach or exceed hurricane wind

  • Community cleverness required
    Researchers need to adapt their institutions and practices in response to torrents of new data ? and need to complement smart science with smart searching.

  • Cool philosophies
    High-energy physicists should not gloss over fundamental conundrums.

  • The hour of diplomacy
    Scientific collaboration between East and West must survive the crisis in Georgia.

  • Cell biology: Cause of death
    Proc. Natl Acad. Sci. USA105, 12497?12502 (2008) 10.1073/pnas.0802773105The bacterial pathogen Vibrio parahaemolyticus has an unusual way of killing cells, researchers report.V. parahaemolyticus causes severe diarrhoea and can be life threatening in people with weakened

  • Geosciences: Clubmoss clues
    Nature Geosci. doi:10.1038/ngeo278 (2008)Spores in herbaria around the world may help to push back the record of atmospheric ozone concentrations, according to Barry Lomax, now at the University of Nottingham, UK, and his co-workers.They think that the quantities

  • Physics: A bolt from the blue
    Phys. Res. Lett.101, 075005 (2008) 10.1103/PhysRevLett.101.075005Bolts of lightning expand by sending out trees of tiny filaments called streamers, which are ionized air channels. Logic dictates that the channel heads should repel one another because they carry the same electric

  • Molecular biology: Precision dumping
    Cell134, 668?678 (2008) 10.1016/j.cell.2008.07.039Editing a molecular tag called polyubiquitin sends two key immune-response proteins into the cellular garbage-disposal system.There are two main ways of attaching one ubiquitin to another within polyubiquitin, and the one chosen often determines whether the target protein

  • Chemistry: Silicon pulls it off
    Science321, 118?190 (2008) 10.1126/science.1159979 Organic molecules containing carbon?fluorine bonds are long-lived atmospheric pollutants that act as powerful greenhouse gases. The secret of their longevity is the stubbornly unreactive nature of these bonds. A catalyst that could turn those tough C?F bonds into C?H

  • Immunology: Hitting 'pause'
    Cell134, 657?667 (2008)10.1016/j.cell.2008.06.049Although senescent cells may appear dormant, they have an important role in protecting the liver from cirrhosis, according to Scott Lowe of Cold Spring Harbor Laboratory in New York and his colleagues.Cirrhosis results from the long-term accumulation of fibrous

  • Geosciences: Goodbye April showers
    Geophys. Res. Lett. doi:10.1029/2008GL034828 (2008)Climate models predict that as Earth warms, the Northern Annular Mode (NAM), a flip-flopping pattern of climate variability in the Northern Hemisphere, will flop more firmly to its low-pressure-near-the-pole state.By studying climate records, Stephanie

  • Neuroscience: Coke heads
    Neuron59, 621?633 (2008) 10.1016/j.neuron.2008.06.020Repeated exposure to cocaine increases the density of connections among the nerve cells in a brain region that is central to motivation and reward. The change seems to stymie long-lasting behaviours associated with chronic

  • Archaeology: Amazonian urbanites
    Science321, 1214?1217 (2008) 10.1126/science.1159769The Amazon is not a pristine wilderness. In fact, there is increasing evidence for sophisticated town planning there long before Europeans arrived.Michael Heckenberger at the University of Florida in Gainesville and his band of archaeologists (pictured) have uncovered

  • Astrophysics: Far off fly-by
    Astrophys. J.683, 722?749 (2008) 10.1086/589632M31, the spiral galaxy nearest the Milky Way, and NGC 205, a nearby dwarf elliptical galaxy, appear to be stuck in an eternal pas de deux. At least, that is what it

  • Journal club
    A microbiologist hopes to disrupt bacterial 'decisions'.Cyclic-di-GMP is small but important. It is an intracellular signalling molecule that controls lifestyle choices in bacteria. When should a bacterium become virulent? When should it differentiate into a new cell type? When might it do better to

  • Better writing and more space needed online
    SirThe World-Wide Web is remarkable as a vehicle for communicating scientific discoveries. Online journals unite distant researchers and inspire worldwide collaborations. However, despite these advantages, there is a growing risk that papers published today are less successful in meeting their objectives than in the

  • Languages: Catalan speakers learn a wider range
    SirJose M. Rojo claims, in his Correspondence 'Schools in a third of Spain teach only in minority languages' (Nature454, 575; 10.1038/454575d2008), that public education is not available in Spanish in schools in Catalonia, Mallorca and Valencia. However, in

  • Languages: Spain's minority-language speakers are bilingual
    SirIn his Correspondence 'Schools in a third of Spain teach only in minority languages' (Nature454, 575; 10.1038/454575d2008), Jose M. Rojo complained about the impossibility of studying in Spanish in one-third of the public schools in Spain. This is,

  • Religion: science is partially based on faith
    SirAndrew Brown's Obituary of John Templeton (Nature454, 290; 2008) and your Editorial ('Templeton's legacy' Nature454, 253?254; 10.1038/454253b2008) both touch upon the philanthropist's interest in science and faith. Some might argue that science

  • Vavilov's vision for genetics was among Stalin's many victims
    SirJan Witkowski's review of Peter Pringle's fascinating and timely book on the famous geneticist Nikolai Vavilov ('Stalin's war on genetic science' Nature454, 577?579; 2008) is informative, but contains some oversimplifications and inaccuracies.The review pays little credit to

  • Message from the heavens may be that there is no message
    SirIn his Opinion piece 'Message from the heavens' (Nature453, 1185; 2008), Martin Kemp tries to discern the meaning behind Maurizio Cattelan's shocking sculpture of Pope John Paul II felled by a meteorite. Although acknowledging that this sculpture has much

  • Senior staff of Mexican institute speak up
    SirWe find that your News story 'Scientists rally to Mexican researchers' plea' (Nature454, 143; 2008) is unjustifiably biased in favour of Harold Kroto and the research group of the Terrones brothers whom he defends.Our institute for scientific and technological

  • Big data: How do your data grow?
    Scientists need to ensure that their results will be managed for the long haul. Maintaining data takes big organization, says Clifford Lynch.

  • Big data: Distilling meaning from data
    Buried in vast streams of data are clues to new science. But we may need to craft new lenses to see them, explain Felice Frankel and Rosalind Reid.

  • A shared digital future?
    Will the possibilities for mass creativity on the Internet be realized or squandered, asks Tony Hey.

  • Virtual similarities
    In his book Secondary Worlds, W. H. Auden wrote that ?present in every human being are two desires, a desire to know the truth about the primary world ... and the desire to make new secondary worlds of our own or, if we cannot

  • Q&A: Museum's metamorphosis is nearly complete
    On the unveiling of the second phase of the Darwin Centre at London's Natural History Museum, Anna Maria Indrio, partner at the Scandinavian architectural firm C. F. M?r, explains how the new £78 million (US$145 million) wing will reveal 20 million of the museum's insect and plant specimens to the public when it opens in September 2009.

  • In Retrospect: Leibniz's Protogaea
    The first English translation of Gottfried Leibniz's earth science treatise records the difficulties of understanding our planet before geologists appreciated deep time, Richard Fortey discovers.

  • Big data: The Harvard computers
    The first mass data crunchers were people, not machines. Sue Nelson looks at the discoveries and legacy of the remarkable women of Harvard's Observatory.

  • Astrophysics: Bringing black holes into focus
    Do black holes exist? Observations at the finest resolution so far indicate that only gross deviations in the behaviour of gravity from that predicted by general relativity can invalidate the case that they do.

  • Immunology: Oxysterols hold T cells in check
    The oxysterol-dependent gene transcription factor LXR? restricts premature expansion of T cells by limiting cellular cholesterol levels. This pathway might be a pharmacological target for regulating immune responses.

  • Experimental physics: A shift in spectroscopy
    Spectroscopic measurement of the energy absorbed or emitted by an object is an invaluable experimental technique. An innovative approach opens the door to the acquisition of previously inaccessible data.

  • Medical imaging: Less is more
    The magnetic resonance imagers used in medicine fill rooms with their large-field magnets. But developments in ultra-low-field devices may give the doctor of tomorrow a more portable version.

  • Small RNAs: The seeds of silence
    Individual microRNA sequences can suppress the production of hundreds of proteins. Reduction of protein levels in this way is often modest, however, and many such RNAs probably collectively fine-tune gene expression.

  • Obituary: Victor Almon McKusick (1921?2008)
    Quiet revolutionary in genetic medicine.

  • Big data: The future of biocuration
    To thrive, the field that links biologists and their data urgently needs structure, recognition and support.

  • Amplitude spectroscopy of a solid-state artificial atom
    The energy-level structure of a quantum system, which has a fundamental role in its behaviour, can be observed as discrete lines and features in absorption and emission spectra. Conventionally, spectra are measured using frequency spectroscopy, whereby the frequency of a harmonic electromagnetic driving field is

  • Widespread changes in protein synthesis induced by microRNAs
    Animal microRNAs (miRNAs) regulate gene expression by inhibiting translation and/or by inducing degradation of target messenger RNAs. It is unknown how much translational control is exerted by miRNAs on a genome-wide scale. We used a new proteomic approach to measure changes in synthesis of several

  • The impact of microRNAs on protein output
    MicroRNAs are endogenous ?23-nucleotide RNAs that can pair to sites in the messenger RNAs of protein-coding genes to downregulate the expression from these messages. MicroRNAs are known to influence the evolution and stability of many mRNAs, but their global impact on protein output had not

  • Type IV collagens regulate BMP signalling in Drosophila
    Dorsal?ventral patterning in vertebrate and invertebrate embryos is mediated by a conserved system of secreted proteins that establishes a bone morphogenetic protein (BMP) gradient. Although the Drosophila embryonic Decapentaplegic (Dpp) gradient has served as a model to understand how morphogen gradients are established, no

  • Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre
    The cores of most galaxies are thought to harbour supermassive black holes, which power galactic nuclei by converting the gravitational energy of accreting matter into radiation. Sagittarius A* (Sgr?A*), the compact source of radio, infrared and X-ray emission at the centre of the Milky Way, is the closest example of this phenomenon, with an estimated black hole mass that is 4,000,000 times that of the Sun. A long-standing astronomical goal is to resolve structures in the innermost accretion flow surrounding Sgr?A*, where strong gravitational fields will distort the appearance of radiation emitted near the black hole. Radio observations at wavelengths of 3.5?mm and 7?mm have detected intrinsic structure in Sgr?A*, but the spatial resolution of observations at these wavelengths is limited by interstellar scattering. Here we report observations at a wavelength of 1.3?mm that set a size of nature07245-m2jpg7444020 microarcseconds on the intrinsic diameter of Sgr?A*. This is less than the expected apparent size of the event horizon of the presumed black hole, suggesting that the bulk of Sgr?A* emission may not be centred on the black hole, but arises in the surrounding accretion flow.

  • Electronic structure of the iron-based superconductor LaOFeP
    The recent discovery of superconductivity in the iron oxypnictide family of compounds has generated intense interest. The layered crystal structure with transition-metal ions in planar square-lattice form and the discovery of spin-density-wave order near 130?K (refs 10, 11) seem to hint at a strong similarity with the copper oxide superconductors. An important current issue is the nature of the ground state of the parent compounds. Two distinct classes of theories, distinguished by the underlying band structure, have been put forward: a local-moment antiferromagnetic ground state in the strong-coupling approach, and an itinerant ground state in the weak-coupling approach. The first approach stresses on-site correlations, proximity to a Mott-insulating state and, thus, the resemblance to the high-transition-temperature copper oxides, whereas the second approach emphasizes the itinerant-electron physics and the interplay between the competing ferromagnetic and antiferromagnetic fluctuations. The debate over the two approaches is partly due to the lack of conclusive experimental information on the electronic structures. Here we report angle-resolved photoemission spectroscopy (ARPES) of LaOFeP (superconducting transition temperature, Tc = 5.9?K), the first-reported iron-based superconductor. Our results favour the itinerant ground state, albeit with band renormalization. In addition, our data reveal important differences between these and copper-based superconductors.

  • Nanoscale double emulsions stabilized by single-component block copolypeptides
    Water-in-oil-in-water emulsions are examples of double emulsions, in which dispersions of small water droplets within larger oil droplets are themselves dispersed in a continuous aqueous phase. Emulsions occur in many forms of processing and are used extensively by the foods, cosmetics and coatings industries. Because of their compartmentalized internal structure, double emulsions can provide advantages over simple oil-in-water emulsions for encapsulation, such as the ability to carry both polar and non-polar cargos, and improved control over release of therapeutic molecules. The preparation of double emulsions typically requires mixtures of surfactants for stability; the formation of double nanoemulsions, where both inner and outer droplets are under 100?nm, has not yet been achieved. Here we show that water-in-oil-in-water double emulsions can be prepared in a simple process and stabilized over many months using single-component, synthetic amphiphilic diblock copolypeptide surfactants. These surfactants even stabilize droplets subjected to extreme flow, leading to direct, mass production of robust double nanoemulsions that are amenable to nanostructured encapsulation applications in foods, cosmetics and drug delivery.

  • Interaction between liquid water and hydroxide revealed by core-hole de-excitation
    The hydroxide ion plays an important role in many chemical and biochemical processes in aqueous solution. But our molecular-level understanding of its unusual and fast transport in water, and of the solvation patterns that allow fast transport, is far from complete. One proposal seeks to explain the properties and behaviour of the hydroxide ion by essentially regarding it as a water molecule that is missing a proton, and by inferring transport mechanisms and hydration structures from those of the excess proton. A competing proposal invokes instead unique and interchanging hydroxide hydration complexes, particularly the hypercoordinated OH-(H2O)4 species and tri-coordinated OH-(H2O)3 that can form a transient hydrogen bond between the H atom of the OH- and a neighbouring water molecule. Here we report measurements of core-level photoelectron emission and intermolecular Coulombic decay for an aqueous hydroxide solution, which show that the hydrated hydroxide ion is capable of transiently donating a hydrogen bond to surrounding water molecules. In agreement with recent experimental studies of hydroxide solutions, our finding thus supports the notion that the hydration structure of the hydroxide ion cannot be inferred from that of the hydrated excess proton.

  • The increasing intensity of the strongest tropical cyclones
    Atlantic tropical cyclones are getting stronger on average, with a 30-year trend that has been related to an increase in ocean temperatures over the Atlantic Ocean and elsewhere. Over the rest of the tropics, however, possible trends in tropical cyclone intensity are less obvious, owing to the unreliability and incompleteness of the observational record and to a restricted focus, in previous trend analyses, on changes in average intensity. Here we overcome these two limitations by examining trends in the upper quantiles of per-cyclone maximum wind speeds (that is, the maximum intensities that cyclones achieve during their lifetimes), estimated from homogeneous data derived from an archive of satellite records. We find significant upward trends for wind speed quantiles above the 70th percentile, with trends as high as 0.3?±?0.09?m?s-1?yr-1 (s.e.) for the strongest cyclones. We note separate upward trends in the estimated lifetime-maximum wind speeds of the very strongest tropical cyclones (99th percentile) over each ocean basin, with the largest increase at this quantile occurring over the North Atlantic, although not all basins show statistically significant increases. Our results are qualitatively consistent with the hypothesis that as the seas warm, the ocean has more energy to convert to tropical cyclone wind.

  • Multimodal warning signals for a multiple predator world
    Aposematism is an anti-predator defence, dependent on a predator?s ability to associate unprofitable prey with a prey-borne signal. Multimodal signals should vary in efficacy according to the sensory systems of different predators; however, until now, the impact of multiple predator classes on the evolution of these signals had not been investigated. Here, using a community-level molecular phylogeny to generate phylogenetically independent contrasts, we show that warning signals of tiger moths vary according to the seasonal and daily activity patterns of birds and bats?predators with divergent sensory capacities. Many tiger moths advertise chemical defence using conspicuous colouration and/or ultrasonic clicks. During spring, when birds are active and bats less so, we found that tiger moths did not produce ultrasonic clicks. Throughout both spring and summer, tiger moths most active during the day were visually conspicuous. Those species emerging later in the season produced ultrasonic clicks; those that were most nocturnal were visually cryptic. Our results indicate that selective pressures from multiple predator classes have distinct roles in the evolution of multimodal warning displays now effective against a single predator class. We also suggest that the evolution of acoustic warning signals may lack the theoretical difficulties associated with the origination of conspicuous colouration.

  • The virophage as a unique parasite of the giant mimivirus
    Viruses are obligate parasites of Eukarya, Archaea and Bacteria. Acanthamoeba polyphaga mimivirus (APMV) is the largest known virus; it grows only in amoeba and is visible under the optical microscope. Mimivirus possesses a 1,185-kilobase double-stranded linear chromosome whose coding capacity is greater than that of numerous bacteria and archaea. Here we describe an icosahedral small virus, Sputnik, 50?nm in size, found associated with a new strain of APMV. Sputnik cannot multiply in Acanthamoeba castellanii but grows rapidly, after an eclipse phase, in the giant virus factory found in amoebae co-infected with APMV. Sputnik growth is deleterious to APMV and results in the production of abortive forms and abnormal capsid assembly of the host virus. The Sputnik genome is an 18.343-kilobase circular double-stranded DNA and contains genes that are linked to viruses infecting each of the three domains of life Eukarya, Archaea and Bacteria. Of the 21 predicted protein-coding genes, eight encode proteins with detectable homologues, including three proteins apparently derived from APMV, a homologue of an archaeal virus integrase, a predicted primase?helicase, a packaging ATPase with homologues in bacteriophages and eukaryotic viruses, a distant homologue of bacterial insertion sequence transposase DNA-binding subunit, and a Zn-ribbon protein. The closest homologues of the last four of these proteins were detected in the Global Ocean Survey environmental data set, suggesting that Sputnik represents a currently unknown family of viruses. Considering its functional analogy with bacteriophages, we classify this virus as a virophage. The virophage could be a vehicle mediating lateral gene transfer between giant viruses.

  • Single-nucleotide mutation rate increases close to insertions/deletions in eukaryotes
    Mutation hotspots are commonly observed in genomic sequences and certain human disease loci, but general mechanisms for their formation remain elusive. Here we investigate the distribution of single-nucleotide changes around insertions/deletions (indels) in six independent genome comparisons, including primates, rodents, fruitfly, rice and yeast. In each of these genomic comparisons, nucleotide divergence (D) is substantially elevated surrounding indels and decreases monotonically to near-background levels over several hundred bases. D is significantly correlated with both size and abundance of nearby indels. In comparisons of closely related species, derived nucleotide substitutions surrounding indels occur in significantly greater numbers in the lineage containing the indel than in the one containing the ancestral (non-indel) allele; the same holds within species for single-nucleotide mutations surrounding polymorphic indels. We propose that heterozygosity for an indel is mutagenic to surrounding sequences, and use yeast genome-wide polymorphism data to estimate the increase in mutation rate. The consistency of these patterns within and between species suggests that indel-associated substitution is a general mutational mechanism.

  • Molecular architecture of native HIV-1 gp120 trimers
    The envelope glycoproteins (Env) of human and simian immunodeficiency viruses (HIV and SIV, respectively) mediate virus binding to the cell surface receptor CD4 on target cells to initiate infection. Env is a heterodimer of a transmembrane glycoprotein (gp41) and a surface glycoprotein (gp120), and forms trimers on the surface of the viral membrane. Using cryo-electron tomography combined with three-dimensional image classification and averaging, we report the three-dimensional structures of trimeric Env displayed on native HIV-1 in the unliganded state, in complex with the broadly neutralizing antibody b12 and in a ternary complex with CD4 and the 17b antibody. By fitting the known crystal structures of the monomeric gp120 core in the b12- and CD4/17b-bound conformations into the density maps derived by electron tomography, we derive molecular models for the native HIV-1 gp120 trimer in unliganded and CD4-bound states. We demonstrate that CD4 binding results in a major reorganization of the Env trimer, causing an outward rotation and displacement of each gp120 monomer. This appears to be coupled with a rearrangement of the gp41 region along the central axis of the trimer, leading to closer contact between the viral and target cell membranes. Our findings elucidate the structure and conformational changes of trimeric HIV-1 gp120 relevant to antibody neutralization and attachment to target cells.

  • Neurogenin 2 controls cortical neuron migration through regulation of Rnd2
    Motility is a universal property of newly generated neurons. How cell migration is coordinately regulated with other aspects of neuron production is not well understood. Here we show that the proneural protein neurogenin 2 (Neurog2), which controls neurogenesis in the embryonic cerebral cortex, directly induces the expression of the small GTP-binding protein Rnd2 (ref. 3) in newly generated mouse cortical neurons before they initiate migration. Rnd2 silencing leads to a defect in radial migration of cortical neurons similar to that observed when the Neurog2 gene is deleted. Remarkably, restoring Rnd2 expression in Neurog2-mutant neurons is sufficient to rescue their ability to migrate. Our results identify Rnd2 as a novel essential regulator of neuronal migration in the cerebral cortex and demonstrate that Rnd2 is a major effector of Neurog2 function in the promotion of migration. Thus, a proneural protein controls the complex cellular behaviour of cell migration through a remarkably direct pathway involving the transcriptional activation of a small GTP-binding protein.

  • Polo-like kinase-1 is activated by aurora A to promote checkpoint recovery
    Polo-like kinase-1 (PLK1) is an essential mitotic kinase regulating multiple aspects of the cell division process. Activation of PLK1 requires phosphorylation of a conserved threonine residue (Thr?210) in the T-loop of the PLK1 kinase domain, but the kinase responsible for this has not yet been affirmatively identified. Here we show that in human cells PLK1 activation occurs several hours before entry into mitosis, and requires aurora?A (AURKA, also known as STK6)-dependent phosphorylation of Thr?210. We find that aurora A can directly phosphorylate PLK1 on Thr?210, and that activity of aurora A towards PLK1 is greatly enhanced by Bora (also known as C13orf34 and FLJ22624), a known cofactor for aurora A (ref. 7). We show that Bora/aurora-A-dependent phosphorylation is a prerequisite for PLK1 to promote mitotic entry after a checkpoint-dependent arrest. Importantly, expression of a PLK1-T210D phospho-mimicking mutant partially overcomes the requirement for aurora A in checkpoint recovery. Taken together, these data demonstrate that the initial activation of PLK1 is a primary function of aurora A.

  • Structure of Epac2 in complex with a cyclic AMP analogue and RAP1B
    Epac proteins are activated by binding of the second messenger cAMP and then act as guanine nucleotide exchange factors for Rap proteins. The Epac proteins are involved in the regulation of cell adhesion and insulin secretion. Here we have determined the structure of Epac2 in complex with a cAMP analogue (Sp-cAMPS) and RAP1B by X-ray crystallography and single particle electron microscopy. The structure represents the cAMP activated state of the Epac2 protein with the RAP1B protein trapped in the course of the exchange reaction. Comparison with the inactive conformation reveals that cAMP binding causes conformational changes that allow the cyclic nucleotide binding domain to swing from a position blocking the Rap binding site towards a docking site at the Ras exchange motif domain.

  • Direct observation of the mechanochemical coupling in myosin Va during processive movement
    Myosin?Va transports intracellular cargoes along actin filaments in cells. This processive, two-headed motor takes multiple 36-nm steps in which the two heads swing forward alternately towards the barbed end of actin driven by ATP hydrolysis. The ability of myosin?Va to move processively is a function of its long lever arm, the high duty ratio of its kinetic cycle and the gating of the kinetics between the two heads such that ADP release from the lead head is greatly retarded. Mechanical studies at the multiple- and the single-molecule level suggest that there is tight coupling (that is, one ATP is hydrolysed per power stroke), but this has not been directly demonstrated. We therefore investigated the coordination between the ATPase mechanism of the two heads of myosin?Va and directly visualized the binding and dissociation of single fluorescently labelled nucleotide molecules, while simultaneously observing the stepping motion of the fluorescently labelled myosin Va as it moved along an actin filament. Here we show that preferential ADP dissociation from the trail head of mouse myosin Va is followed by ATP binding and a synchronous 36-nm step. Even at low ATP concentrations, the myosin Va molecule retained at least one nucleotide (ADP in the lead head position) when moving. Thus, we directly demonstrate tight coupling between myosin Va movement and the binding and dissociation of nucleotide by simultaneously imaging with near nanometre precision.

  • Gigatech
    Testing, testing ...


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